Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 05/11/14
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1052 PM EDT SAT MAY 10 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE ACROSS LATE TONIGHT. HIGH PRESSURE THEN
BUILDS OVER THE AREA ON SUNDAY AND SUNDAY NIGHT. HIGH PRESSURE
DEPARTS ON MONDAY...AND THEN A SERIES OF FRONTAL BOUNDARIES AND
WEAK LOW PRESSURE SYSTEMS WILL MOVE ACROSS THE REGION THROUGH THE
MIDDLE OF THE WEEK. A STRONGER COLD FRONT IMPACTS THE REGION LATE
NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
02Z SATELLITE AND RADAR IMAGERY INDICATING FINAL PUSH OF PCPN
CROSSING EASTERN PA INTO WESTERN NJ OUT AHEAD OF THE COLD FRONT
AND ASSOCIATED WITH A PASSING SHORTWAVE. MINIMAL INSTABILITY IN
PLACE OVER THIS AREA...SO WHILE AN ISO TSTM REMAINS PSBL...THE
THREAT LEVEL IS QUICKLY DIMINISHING...WITH THE THINKING THE
THUNDER THREAT SHOULD SUBSIDE AFTER 06Z. HRRR HAS BEEN CONSISTENT
IN PUSHING PCPN THROUGH BETWEEN 03-07Z...LINGERING OVER FAR
EASTERN LI AND SE CT UNTIL 09Z...WHEN THE FRONT FINALLY CLEARS THE
AREA. HAVE ADJUSTED POPS TO ACCOUNT FOR THIS. NOT ANTICIPATING ANY
FURTHER SEVERE THREATS NOR FLOODING ISSUES.
ALSO...WITH RATHER LIGHT WESTERLY FLOW BEHIND THE FRONT...STILL THINKING
LOW LEVELS WILL BE SLOWER TO DRY OUT LATE TONIGHT.
THEREFORE...CONTINUE TO HAVE PATCHY FOG DEVELOPING LATE. LOWS
WERE A BLEND OF NAM12 AND MET GUIDANCE...HIGHER SIDE OF GUIDANCE.
TEMPS AND DEW PTS GENERALLY ON TRACK AS OF LATE THIS EVENING.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/...
BEHIND THE COLD FRONT...MID LEVEL RIDGING WITH HIGH PRESSURE
BUILDING IN AT THE SURFACE FROM THE SOUTH AND WEST WILL PROMOTE
DRY WEATHER DURING THIS PERIOD. WITH THE WESTERLY FLOW
SUNDAY...EXPECTING A QUICK INCREASE TO TEMPERATURES IN THE MORNING
WITH HIGHS WELL ABOVE NORMAL ONCE AGAIN...IN THE MID 70S TO LOWER
80S RANGE FOR MOST PLACES. THE JET STREAM ALOFT WILL BE LIFTING
FARTHER NORTH OF THE REGION WITH THE RIDGING. HIGHS WERE TAKEN
FROM MAVS AND INCREASED TWO DEGREES. SKIES WILL BE CLEARING SUNDAY
AND THESE MOSTLY CLEAR SKIES LINGER INTO SUNDAY NIGHT. LOWS SUNDAY
NIGHT WILL BE COOLER THAN OF RECENT NIGHTS WITH RADIATIONAL
COOLING AS WINDS WILL BE LIGHT. LOWS SUNDAY NIGHT WERE TAKEN FROM
ECS AND CONVEY A RANGE FROM THE MID 40S ACROSS RURAL AND INTERIOR
LOCATIONS TO THE LOWER 60S NEAR NYC.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
HIGH PRES DEPARTS ON MONDAY AS A DEEP UPPER TROUGH DIGS INTO THE
CENTRAL U.S. THIS TROUGH WILL EXTEND FROM CANADA INTO THE GULF OF
MEXICO...AND SFC LOW PRES WILL DEVELOP OVER THE WESTERN GREAT LAKES
BEFORE TRACKING TO THE NORTHEAST INTO CANADA. MEANWHILE...A WARM
FRONT APPROACHES ON MONDAY...AND THEN WEAK LOW PRES FORMS ALONG THE
BOUNDARY AS IT LIFTS TO THE NORTH. THAT BOUNDARY WILL BECOME NEARLY
STATIONARY NORTH OF THE REGION ON TUESDAY. AS A RESULT...WILL EXPECT
SCATTERED SHOWERS AND TSTMS TO DEVELOP MONDAY AFTERNOON...MAINLY
ACROSS NORTHERN ZONES. UNSETTLED WEATHER CONTINUES INTO TUESDAY AS
HIGH PRES OVER EASTERN CANADA DROPS SOUTH INTO THE GOLF OF MAINE.
THE STATIONARY FRONT NORTH OF THE AREA WILL PUSH TO THE SOUTH AS A
BACK DOOR COLD FRONT...AND THEN THE HIGH ANCHORS ITSELF OVER THE
WESTERN ATLANTIC THROUGH THE END OF THE WEEK.
THE UPPER TROUGH OVER THE MIDWEST WILL SLOWLY TRACK EAST...BUT WILL
EFFECTIVELY BECOME BLOCKED BY THE OFFSHORE HIGH. SEVERAL WEAK
IMPULSES WILL DEVELOP AT THE BASE OF THE TROUGH...AND THOSE WILL
TRACK TOWARDS THE REGION...KEEPING UNSETTLED WEATHER IN THE FORECAST
THROUGH THE END OF THE WEEK.
THE HIGH MOVES TO THE EAST THURSDAY NIGHT...AND THEN THE UPPER
TROUGH MOVES INTO THE EASTERN U.S. THERE ARE SOME INDICATIONS THAT
THE TROUGH BECOMES NEGATIVELY TILTED...AND THEN LOW PRES WILL
DEVELOP OVER THE MID-ATLANTIC BEFORE MOVING THROUGH THE REGION
THURSDAY NIGHT THROUGH FRIDAY. WILL BUMP UP POPS TO LIKELY FOR MOST
OF THE REGION FOR THAT TIME FRAME. COULD BE SOME LINGERING SHOWERS
INTO SATURDAY AS SEVERAL STRONG SHORTWAVES DIVE INTO THE REGION AS
THE TROUGH MOVES OVERHEAD.
SUMMER-LIKE TEMPS CONTINUE ON MONDAY WITH HIGHS WELL ABOVE
NORMAL...TOPPING OFF IN THE LOW 80S WEST OF THE HUDSON RIVER AND IN
THE MID TO UPPER 70S MOST ELSEWHERE...AND COOLER NEAR THE COASTS.
TEMPS RETURN CLOSER TO NORMAL ON TUESDAY...TOPPING OFF IN THE UPPER
60S TO LOWER 70S WITH THE WARMEST TEMPS ONCE AGAIN WEST OF THE
HUDSON RIVER. BY WEDNESDAY...BEHIND THE BACK DOOR COLD FRONT AND
WITH ONSHORE FLOW...HIGHS WILL RANGE FROM THE UPPER 50S NEAR THE
COASTS TO THE MID 60S ACROSS THE INTERIOR. TEMPS WILL THEN TOP OFF
AROUND NORMAL TO CLOSE OUT THE WEEK...GENERALLY IN THE UPPER 60S.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
MAINLY VFR CONDITIONS TONIGHT INTO TOMORROW WITH A COLD FRONT
PASSING THROUGH THE REGION LATER TONIGHT.
NEXT ROUND OF LIGHT TO MOD SHOWERS PSBL...GENERALLY BETWEEN
02-07Z. ISO TSTM REMAINS PSBL...BUT TOO LOW CONFIDENCE TO INCLUDE.
WHILE CIGS COULD BRIEFLY DROP TO AROUND 3000 FT...MAINLY EXPECTING
4000-5000 FT CIGS WITH ANY PCPN. VIS SHOULD REMAIN 5SM OR GREATER
AS WELL.
WSW WINDS WILL GRADUALLY SHIFT OVERNIGHT...BCMG WNW BEHIND THE
FRONT LATE TONIGHT. WINDS WILL PICK UP TOMORROW...WITH GUSTS
MIXING IN AFTR 15Z. WINDS TOMORROW MORNING/AFTN WILL HOVER AROUND
300 TRUE.
ONCE THE PCPN TAPERS OFF TONIGHT...NOT EXPECTING ANY FURTHER PCPN CONCERNS
THROUGH SUNDAY.
.OUTLOOK FOR 03Z MON THROUGH THURS...
.SUN NIGHT-MON...VFR.
.TUES-THURS...GENERALLY VFR WITH PERIODS OF MVFR OR LOWER WITH
PCPN.
&&
.MARINE...
PATCHY FOG CAN BE EXPECTED ACROSS THE WATERS TONIGHT WITH MOIST
LOW LEVELS. WINDS AND SEAS DIMINISHING TONIGHT...AND THOUGH WINDS
MAY BRIEFLY INCREASE IN THE WAKE OF THE COLD FRONT...NOT
ANTICIPATING ENOUGH TO REACH SCA CRITERIA ONCE AGAIN.
THEREFORE...HAVE CANCELLED THE SCA ON THE OCEAN WATERS.
SUB-SCA CONDITIONS ON TAP FOR SUNDAY INTO THE START THE NEW WEEK
WITH HIGH PRESSURE IN CONTROL. BY THE MIDDLE OF NEXT WEEK...SMALL
CRAFT CONDITIONS RETURN AS A PERSISTENT ONSHORE FLOW WILL HELP
PUSH OCEAN SEAS UP TO 3-5 FT.
&&
.HYDROLOGY...
UP TO AROUND A QUARTER INCH OF BASIN AVERAGE QPF IS POSSIBLE
THROUGH THE REMAINDER OF THE NIGHT. ANY FLOODING POTENTIAL IS
EXPECTED TO BE GENERALLY MINOR...PARTICULARLY FOR THOSE LOCATIONS
GETTING MULTIPLE ROUNDS OF SHOWERS AND THUNDERSTORMS.
SCATTERED SHOWERS/TSTMS COULD PRODUCE LOCALLY HEAVY RAIN FOR MOST OF
THE UPCOMING WEEK...BUT WIDESPREAD ORGANIZED PRECIPITATION OF 1/2"
QPF OR MORE WILL HOLD OFF UNTIL LATE NEXT WEEK WHEN LOW PRESSURE
TRACKS THROUGH THE REGION.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...JM/MPS
NEAR TERM...JM/SEARS
SHORT TERM...JM
LONG TERM...MPS
AVIATION...SEARS
MARINE...JM/SEARS/MPS
HYDROLOGY...JM/SEARS/MPS
AREA FORECAST DISCUSSION
NWS NEW YORK NY
746 PM EDT SAT MAY 10 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE ACROSS LATE TONIGHT. HIGH PRESSURE THEN
BUILDS OVER THE AREA ON SUNDAY AND SUNDAY NIGHT. HIGH PRESSURE
DEPARTS ON MONDAY...AND THEN A SERIES OF FRONTAL BOUNDARIES AND
WEAK LOW PRESSURE SYSTEMS WILL MOVE ACROSS THE REGION THROUGH THE
MIDDLE OF THE WEEK. A STRONGER COLD FRONT IMPACTS THE REGION LATE
NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
SOME BREAK IN CONVECTIVE ACTIVITY WILL BE SEEN ACROSS MUCH OF THE
REGION OUTSIDE OF INTERIOR SOUTHERN CT BEFORE 10 PM. SOME
SCATTERED CONVECTION WILL STILL BE IN THE FORECAST THIS EVENING.
THE CHANCE INCREASES LATER THIS EVENING WHEN ANOTHER AREA OF
SHOWERS WILL BE APPROACHING FROM SOUTH CENTRAL PA. THIS IS MODELED
BY THE HRRR TO MOVE THROUGH BETWEEN 03-07Z. INSTABILITY WILL BE
LOWERING GOING THROUGH THE EVENING...ALLOWING THUNDERSTORMS TO
BECOME LESS IN COVERAGE. OTHERWISE...JUST SOME MINOR ADJUSTMENTS
MADE TO TEMPS AND DEWPOINTS WITH NO OTHER REMARKABLE CHANGES MADE.
FOR THE NEXT FEW ROUNDS OF CONVECTION BACK IN PA THROUGH CENTRAL
NY...THEY WILL BE ARRIVING INTO A COOLER BUT STILL MOIST AIRMASS
LATER THIS EVENING. EXPECTING THE THUNDERSTORMS TO BE LESS
COVERAGE GOING TO MID TO LATE EVENING AS TEMPERATURES COOL AND
FORCING JUST REMAINS AHEAD OF THE SHORTWAVE AND COLD FRONT AT THE
SURFACE. THE JET STREAM ALOFT WILL MOVE NEAR THE REGION THIS
EVENING AND SHOULD KEEP DIVERGENCE GOING ALOFT...ALLOWING FOR A
HIGHER CHANCE OF PRECIP.
ALSO...WITH RATHER LIGHT WESTERLY FLOW BEHIND THE FRONT...THINKING
LOW LEVELS WILL BE SLOWER TO DRY OUT LATE TONIGHT.
THEREFORE...HAVE PATCHY FOG DEVELOPING LATE. LOWS WERE A BLEND OF
NAM12 AND MET GUIDANCE...HIGHER SIDE OF GUIDANCE.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/...
BEHIND THE COLD FRONT...MID LEVEL RIDGING WITH HIGH PRESSURE
BUILDING IN AT THE SURFACE FROM THE SOUTH AND WEST WILL PROMOTE
DRY WEATHER DURING THIS PERIOD. WITH THE WESTERLY FLOW
SUNDAY...EXPECTING A QUICK INCREASE TO TEMPERATURES IN THE MORNING
WITH HIGHS WELL ABOVE NORMAL ONCE AGAIN...IN THE MID 70S TO LOWER
80S RANGE FOR MOST PLACES. THE JET STREAM ALOFT WILL BE LIFTING
FARTHER NORTH OF THE REGION WITH THE RIDGING. HIGHS WERE TAKEN
FROM MAVS AND INCREASED TWO DEGREES. SKIES WILL BE CLEARING SUNDAY
AND THESE MOSTLY CLEAR SKIES LINGER INTO SUNDAY NIGHT. LOWS SUNDAY
NIGHT WILL BE COOLER THAN OF RECENT NIGHTS WITH RADIATIONAL
COOLING AS WINDS WILL BE LIGHT. LOWS SUNDAY NIGHT WERE TAKEN FROM
ECS AND CONVEY A RANGE FROM THE MID 40S ACROSS RURAL AND INTERIOR
LOCATIONS TO THE LOWER 60S NEAR NYC.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
HIGH PRES DEPARTS ON MONDAY AS A DEEP UPPER TROUGH DIGS INTO THE
CENTRAL U.S. THIS TROUGH WILL EXTEND FROM CANADA INTO THE GULF OF
MEXICO...AND SFC LOW PRES WILL DEVELOP OVER THE WESTERN GREAT LAKES
BEFORE TRACKING TO THE NORTHEAST INTO CANADA. MEANWHILE...A WARM
FRONT APPROACHES ON MONDAY...AND THEN WEAK LOW PRES FORMS ALONG THE
BOUNDARY AS IT LIFTS TO THE NORTH. THAT BOUNDARY WILL BECOME NEARLY
STATIONARY NORTH OF THE REGION ON TUESDAY. AS A RESULT...WILL EXPECT
SCATTERED SHOWERS AND TSTMS TO DEVELOP MONDAY AFTERNOON...MAINLY
ACROSS NORTHERN ZONES. UNSETTLED WEATHER CONTINUES INTO TUESDAY AS
HIGH PRES OVER EASTERN CANADA DROPS SOUTH INTO THE GOLF OF MAINE.
THE STATIONARY FRONT NORTH OF THE AREA WILL PUSH TO THE SOUTH AS A
BACK DOOR COLD FRONT...AND THEN THE HIGH ANCHORS ITSELF OVER THE
WESTERN ATLANTIC THROUGH THE END OF THE WEEK.
THE UPPER TROUGH OVER THE MIDWEST WILL SLOWLY TRACK EAST...BUT WILL
EFFECTIVELY BECOME BLOCKED BY THE OFFSHORE HIGH. SEVERAL WEAK
IMPULSES WILL DEVELOP AT THE BASE OF THE TROUGH...AND THOSE WILL
TRACK TOWARDS THE REGION...KEEPING UNSETTLED WEATHER IN THE FORECAST
THROUGH THE END OF THE WEEK.
THE HIGH MOVES TO THE EAST THURSDAY NIGHT...AND THEN THE UPPER
TROUGH MOVES INTO THE EASTERN U.S. THERE ARE SOME INDICATIONS THAT
THE TROUGH BECOMES NEGATIVELY TILTED...AND THEN LOW PRES WILL
DEVELOP OVER THE MID-ATLANTIC BEFORE MOVING THROUGH THE REGION
THURSDAY NIGHT THROUGH FRIDAY. WILL BUMP UP POPS TO LIKELY FOR MOST
OF THE REGION FOR THAT TIME FRAME. COULD BE SOME LINGERING SHOWERS
INTO SATURDAY AS SEVERAL STRONG SHORTWAVES DIVE INTO THE REGION AS
THE TROUGH MOVES OVERHEAD.
SUMMER-LIKE TEMPS CONTINUE ON MONDAY WITH HIGHS WELL ABOVE
NORMAL...TOPPING OFF IN THE LOW 80S WEST OF THE HUDSON RIVER AND IN
THE MID TO UPPER 70S MOST ELSEWHERE...AND COOLER NEAR THE COASTS.
TEMPS RETURN CLOSER TO NORMAL ON TUESDAY...TOPPING OFF IN THE UPPER
60S TO LOWER 70S WITH THE WARMEST TEMPS ONCE AGAIN WEST OF THE
HUDSON RIVER. BY WEDNESDAY...BEHIND THE BACK DOOR COLD FRONT AND
WITH ONSHORE FLOW...HIGHS WILL RANGE FROM THE UPPER 50S NEAR THE
COASTS TO THE MID 60S ACROSS THE INTERIOR. TEMPS WILL THEN TOP OFF
AROUND NORMAL TO CLOSE OUT THE WEEK...GENERALLY IN THE UPPER 60S.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
MAINLY VFR CONDITIONS TONIGHT INTO TOMORROW WITH A COLD FRONT
PASSING THROUGH THE REGION LATER TONIGHT.
BREAK IN PCPN LATE THIS EVENING...WITH ANOTHER ROUND OF LIGHT TO
MOD SHOWERS PSBL...GENERALLY BETWEEN 02-07Z. ISO TSTM REMAINS
PSBL...BUT TOO LOW CONFIDENCE TO INCLUDE. WHILE CIGS COULD
BRIEFLY DROP TO AROUND 3000 FT...MAINLY EXPECTING 4000-5000 FT
CIGS WITH ANY PCPN. VIS SHOULD REMAIN 5SM OR GREATER AS WELL.
WSW WINDS WILL GRADUALLY SHIFT OVERNIGHT...BCMG WNW BEHIND THE
FRONT LATE TONIGHT. GUSTS 15-20 KTS STILL PSBL PRIOR TO 06Z...WITH
WINDS THEN DIMINISHING AS THE FRONT PASSES. WINDS WILL PICK UP
TOMORROW...WITH GUSTS MIXING IN AFTR 15Z. WINDS TOMORROW
MORNING/AFTN WILL HOVER AROUND 300 TRUE.
ONCE THE PCPN TAPERS OFF TONIGHT...NOT EXPECTING ANY FURTHER PCPN CONCERNS
THROUGH SUNDAY.
.OUTLOOK FOR 00Z MON THROUGH THURS...
.MON...VFR.
.TUES-THURS...GENERALLY VFR WITH PERIODS OF MVFR OR LOWER WITH
PCPN.
&&
.MARINE...
PATCHY FOG CAN BE EXPECTED ACROSS THE WATERS TONIGHT WITH MOIST
LOW LEVELS. SCA CONDITIONS STILL EXPECTED FOR THE OCEAN BUT
SYNOPTIC GUSTS WILL BE MARGINAL...NEAR 25 KT BUT FREQUENCY MAY BE
MORE OCCASIONAL WITH THIS. HOWEVER...EXPECTING THE INCREASING SW
FETCH WILL HELP BUILD SEAS AS WELL TO 5 FT ACROSS THE OCEAN ZONES.
JUST EASTERN OCEAN ZONES HAVE SCA CONDITIONS THROUGH TONIGHT WITH
WESTERN OCEAN UNTIL MIDNIGHT. FOR SUNDAY AND SUNDAY NIGHT...SUB
SCA CONDITIONS ARE EXPECTED WITH HIGH PRESSURE IN CONTROL.
SUB-SCA CONDITIONS ON TAP FOR THE START THE NEW WEEK. BY THE MIDDLE
OF NEXT WEEK...SMALL CRAFT CONDITIONS RETURN AS A PERSISTENT ONSHORE
FLOW WILL HELP PUSH OCEAN SEAS UP TO 3-5 FT.
&&
.HYDROLOGY...
AROUND THREE TENTHS TO A HALF INCH OF BASIN AVERAGE QPF IS
EXPECTED THROUGH TONIGHT WITH SOME HIGHER AMOUNTS FROM CONVECTION.
ANY FLOODING POTENTIAL IS EXPECTED TO BE GENERALLY
MINOR...PARTICULARLY FOR THOSE LOCATIONS GETTING MULTIPLE ROUNDS
OF SHOWERS AND THUNDERSTORMS.
SCATTERED SHOWERS/TSTMS COULD PRODUCE LOCALLY HEAVY RAIN FOR MOST OF
THE UPCOMING WEEK...BUT WIDESPREAD ORGANIZED PRECIPITATION OF 1/2"
QPF OR MORE WILL HOLD OFF UNTIL LATE NEXT WEEK WHEN LOW PRESSURE
TRACKS THROUGH THE REGION.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR ANZ355.
SMALL CRAFT ADVISORY UNTIL 6 AM EDT SUNDAY FOR ANZ350-353.
&&
$$
SYNOPSIS...JM/MPS
NEAR TERM...JM
SHORT TERM...JM
LONG TERM...MPS
AVIATION...SEARS
MARINE...JM/MPS
HYDROLOGY...JM/MPS
AREA FORECAST DISCUSSION
NWS TAUNTON MA
509 PM EDT FRI MAY 9 2014
.SYNOPSIS...
A WARM FRONT WILL APPROACH TONIGHT BRINGING A PERIOD OF SCATTERED
SHOWERS BEFORE IT LIFTS INTO NORTHERN NEW ENGLAND SATURDAY. BEHIND
THE FRONT A WARMER AND MORE HUMID AIRMASS OVERSPREADS THE REGION
SATURDAY. A COLD FRONT WILL MOVE ACROSS THE AREA LATE SATURDAY
NIGHT INTO EARLY SUNDAY MORNING...YIELDING A ROUND OF SCATTERED
SHOWERS. HIGH PRESSURE BUILDS IN FOR MOTHERS DAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
345 PM UPDATE...
WARM FRONT ACROSS WESTERN PA AND NY WILL APPROACH THE REGION LATER
TONIGHT. BEFORE THEN COOL PREFRONTAL AIRMASS REMAINS OVER SOUTHERN
NEW ENGLAND AS ONSHORE FLOW MAINTAINS COOL MOIST SHALLOW AIRMASS.
WATER VAPOR IMAGERY ALONG WITH MODEL CROSS SECTIONS AND TIME
SECTIONS REVEAL MID LEVEL DRY AIR OVERSPREAD THE REGION AS WELL.
THIS COMBINED WITH MOIST SHALLOW ONSHORE FLOW IS RESULTING IN
AREAS OF DRIZZLE AND FOG ESPECIALLY IN THE CT RVR VLY AND THE
HIGHER TERRAIN /UPSLOPE FLOW/. THIS WILL BECOME MORE WIDESPREAD
THIS EVENING ESPECIALLY WITH SUNSET. THUS NO APPRECIABLE RAINFALL
THIS EVENING. NOT A WASHOUT JUST SPOTTY LIGHT RAIN/DRIZZLE. LAST
SEVERAL RUNS OF THE HRRR SUPPORT THIS THINKING AS WELL.
LATER TONIGHT WARM FRONT ENTERS THE REGION WITH RAIN BECOMING
MORE WIDESPREAD AS MODELS INDICATE MODEST ISENTROPIC LIFT/UPGLIDE
ACROSS THE REGION 06-12Z. MARGINAL INSTABILITY ALOFT TO SUPPORT A
VERY LOW RISK OF AN ISOLATED TSTM WITH LOCALLY BRIEF HEAVY
DOWNPOUR TOWARD SUNRISE. HOWEVER MUCH OF THE ACTIVITY SHOULD BE ON
THE LIGHT SIDE.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
SATURDAY...WARM FRONT LIFTS NORTH OF THE REGION BY MID TO LATE
MORNING WITH WARM SECTOR OVERSPREADING SOUTHERN NEW ENGLAND.
DEFINITELY A BIT OF A SUMMER-ISH FEEL TO THE AIRMASS TOMORROW WITH
MAY SUNSHINE LIFTING TEMPS INTO THE 70S AND DEW PTS IN THE L60S.
AS FOR INSTABILITY DETERMINISTIC AND ENSEMBLE GUIDANCE SUGGEST
ONLY 200-500 J/KG OF MU AND MEAN CAPE TOMORROW AFTERNOON. NOT MUCH
OF A TRIGGER TOMORROW AFTERNOON AS MID LEVEL TROUGH REMAINS WELL
TO THE WEST ALONG WITH ATTENDING COLD FRONT. THUS THINKING AREAL
COVERAGE OF ANY SHOWERS WILL BE ISOLATED TO WIDELY SCATTERED.
GIVEN MU CAPES ARE ONLY 500J/KG OR LESS ALONG WITH MARGINAL WIND
FIELDS ALOFT...ANY TSTMS SHOULD BE ISOLATED AND NON SEVERE. GIVEN
THE HIGHER PWAT AIRMASS CAN`T RULE OUT A BRIEF HEAVY DOWNPOUR.
OTHERWISE A TYPICAL LATE WARM SPRING AFTERNOON WITH ISOLATED-
WIDELY SCATTERED SHOWERS. ANY MORNING FOG WILL BURN OFF BY MIDDAY.
SATURDAY NIGHT...SHOWERS MAY BECOME MORE WIDESPREAD AS COLD FRONT
APPROACHES ALONG WITH POSSIBLE SURFACE WAVE ON THE FRONT. THIS
WOULD RESULT IN SHOWERS MOST NUMEROUS ALONG THE SOUTH COAST. LOW
RISK OF AN ISOLATED TSTM WITH HEAVY RAINFALL. IMPROVING CONDITIONS
TOWARD 12Z SUN FROM WEST TO EAST. GIVEN POST FRONTAL AIRMASS
DOESNT ARRIVE UNTIL SUNDAY IT WILL BE A MILD NIGHT.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGHLIGHTS...
* DRY...WARM WEATHER FOR MOTHERS DAY AND MONDAY
* BACKDOOR COLD FRONT MOVES INLAND MONDAY NIGHT INTO TUESDAY WITH
SCATTERED SHOWERS
* NEAR TO BELOW NORMAL TEMPS WITH SPOTTY SHOWERS WEDNESDAY
THROUGH FRIDAY
MODEL CONFIDENCE AND PREFERENCES...
NOTING THAT THE 06Z AND 12Z GFS OP RUNS ALONG WITH 12Z GGEM HAVE
COME ON BOARD WITH THE LAST SEVERAL RUNS OF THE ECMWF WITH MAJOR
CHANGES IN THE UPPER LEVEL LONG WAVE PATTERN EARLY NEXT WEEK. NOW
EXPECTING A BUILDING RIDGE ACROSS THE EASTERN U.S. WITH DEEPENING
TROUGH OVER THE CENTRAL U.S. EARLY NEXT WEEK. AS THE RIDGE BUILDS
ALOFT...SURFACE RIDGING ALSO BUILDS ACROSS QUEBEC AND LABRADOR
THEN SHIFTS DOWN THE ATLC COAST...CAUSING A BACKDOOR COLD FRONT
TO CROSS THE REGION FROM NE TO SW AROUND THE LATE MON NIGHT OR TUE
TIMEFRAME. THE FRONT WILL TEND TO STALL MAINLY ACROSS
EASTERN/CENTRAL NY STATE INTO N NJ. SO...WILL LIKELY SEE NEAR OR
BELOW NORMAL TEMPS IN THE MID TO LATTER PORTIONS OF NEXT WEEK WITH
MARITIME AIR OFF THE COLD OCEAN /SEA SURFACE TEMPS IN THE UPPER
40S/. TIMING OF MIGRATION OF THE UPPER TROUGH EASTWARD OUT OF THE
GREAT LAKES AND OHIO VALLEY LATE NEXT WEEK LENDS TO LOWER
CONFIDENCE WITH THE APPROACH OF SURFACE COLD FRONT AS IT BUMPS INTO
THE HIGH AMPLITUDE SURFACE AND UPPER RIDGES.
USED A BLEND OF MOST MODEL GUIDANCE FOR THIS PACKAGE...INCLUDING
WPC GUIDANCE WHICH ALSO INCORPORATED ENSEMBLE MEANS.
DETAILS...
SUNDAY...
WILL SEE A DRY AND MILD SPRING DAY FOR MOTHERS DAY AS WEAK HIGH
PRES RIDGE CROSSES THE REGION. WILL BE A BREEZY DAY WITH W WINDS
GUSTING UP TO 20-25 MPH...HIGHEST WELL INLAND. EXPECT HIGHS MAINLY
IN THE 70S...EXCEPT A BIT COOLER ALONG THE IMMEDIATE COAST. CLOUDS
WILL START TO INCREASE ACROSS N CT/W MA AFTER MIDNIGHT.
MONDAY...
ISENTROPIC LIFT MOVES IN ACROSS THE REGION AS WARM FRONT BEGINS TO
APPROACH. HOWEVER...AS RIDGING BUILDS TO THE W...THIS FRONT HANGS
UP ACROSS THE REGION. EXPECT SOME SCT SHOWERS TO MOVE ACROSS MON
AFTERNOON/NIGHT. ALSO NOTING SOME ELEVATED CONVECTION POSSIBLE
ALONG WITH LIFTED INDICES DROPPING AT OR BELOW ZERO AS THE DAY
PROGRESSES. HAVE ALSO MENTIONED ISOLD THUNDER. COULD BE A RATHER
MILD DAY WITH SOME READINGS POSSIBLY CLOSE TO 80 WELL
INLAND...BUT UNCERTAIN OF THIS DUE TO STALLING FRONT ACROSS THE
REGION. CURRENT MODELS SUGGEST THAT HIGH PRES WILL BEGIN TO SURGE
DOWN FROM MAINE LATE MON NIGHT...SO STALLED FRONT COULD BEGIN TO
SHIFT S-SW. SOMETHING TO MONITOR.
TUESDAY...
MODELS HAVE COME IN LINE IN PUSHING BACKDOOR FRONT ACROSS THE
REGION...FROM NE-SW DURING THE DAY. WILL STILL SEE SOME SCT
SHOWERS BUT SHOULD PUSH FROM E TO W DURING THE AFTERNOON. MAY
STILL SEE SOME ISOLD THUNDER ACROSS N CT/RI THROUGH ABOUT
MIDDAY...THEN WILL PUSH OFF THE S COAST. E-NE WINDS WILL BE GUSTY
ALONG THE E COAST...POSSIBLY UP TO AROUND 25 MPH DURING TUE
AFTERNOON/EVENING. TEMPS WILL RANGE FROM THE UPPER 50S TO MID 60S
ALONG THE E COAST TO THE LOWER-MID 70S ACROSS THE CT VALLEY. WILL
BE CHILLY TUE NIGHT WITH LOWS MAINLY IN THE MID-UPPER 40S WITH
SOME LOWER 50S IN THE LOWER CT VALLEY.
WEDNESDAY THROUGH FRIDAY...
LARGE H5 RIDGING BUILDS ACROSS THE EASTERN U.S. WHILE TROUGH DIGS
ACROSS CENTRAL AREAS. THIS WILL SLOW SURFACE SYSTEMS DOWN AS FRONT
STALLS ACROSS EASTERN NY STATE INTO N NJ. EXPECT SLIGHT CHANCE TO
LOW CHANCE POPS TO LINGER ACROSS CT VALLEY AND E SLOPES OF THE
BERKSHIRES INTO WED NIGHT...THEN MAY START TO SHIFT E AS UPPER
TROUGH/SURFACE COLD FRONT MAY START TO APPROACH THOUGH TIMING IS
IN QUESTION. EXPECT HIGHS EACH DAY TO RUN CLOSE TO OR UP TO 5
DEGS BELOW SEASONAL NORMS.
MODELS DO DIVERGE ON HOW IT RESOLVES THEIR TIMING OF THE UPPER
TROUGH INTO THE EASTERN U.S...POSSIBLY NOT UNTIL NEXT WEEKEND.
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH FRIDAY NIGHT/...LOW CONFIDENCE.
THRU 00Z...LOW CONFIDENCE FORECAST AS TIMING OF IFR CONDITIONS
IMPROVING TO MVFR STILL SOMEWHAT UNCERTAIN. WHERE IFR EXISTS NOW
THINK WE WILL SEE SOME BRIEF IMPROVEMENT TO MVFR AFTER 21Z AS
WINDS SHIFT FROM NE TO SE. ELSEWHERE MVFR SHOULD PREVAIL. AS FOR
THE CT RVR VLY MARGINAL IFR/MVFR WILL CONTINUE. PATCHY FOG AND
DRIZZLE POSSIBLE ALL TERMINALS. ALTHOUGH HEAVY RAIN/THUNDER NOT
EXPECTED.
AFTER 00Z...MVFR WILL TREND TO IFR AS THE NIGHT PROGRESSES.
PATCHY FOG AND DRIZZLE POSSIBLE ALL TERMINALS. BETTER CHANCE OF
WIDESPREAD RAIN TOWARD MORNING. VERY LOW RISK OF ISOLATED THUNDER
TOWARD 12Z.
SATURDAY...ANY LEFTOVER IFR IN THE MORNING WILL LIFT TO MVFR OR
EVEN VFR TOWARD MIDDAY AND ESPECIALLY DURING THE AFTERNOON.
ISOLATED-SCATTERED SHOWERS EARLY ACROSS EASTERN MA AND RI. THEN
ANOTHER ROUND OF ISOLATED-SCATTERED SHOWERS DURING THE AFTERNOON
WITH A VERY LOW RISK OF AN ISOLATED TSTM.
SAT NIGHT...SHOWERS SHOULD BECOME MORE NUMEROUS ESPECIALLY ALONG
THE SOUTH COAST. SOME HEAVY RAIN POSSIBLE. AS FOR CIGS/VSBYS ANY
EARLY VFR CONDITIONS QUICKLY LOWER TO MVFR AND EVENTUALLY IFR
OVERNIGHT FROM WEST TO EAST.
KBOS TERMINAL...LOW CONFIDENCE. IFR SHOULD LIMIT BRIEFLY TO MVFR
AFTER 21Z AS WINDS SHIFT FROM NE TO SE AND THEN S. MVFR LOWERS TO
IFR LATER TONIGHT AS SHOWERS BECOME MORE NUMEROUS TOWARD 12Z SAT.
THEN CONDITIONS IMPROVE TO MVFR AND EVENTUALLY VFR SAT AFTERNOON.
ISOLATED-SCATTERED AFTERNOON SHOWERS.
KBDL TERMINAL...LOW CONFIDENCE. IFR CONDITIONS IN THE CT RVR VLY
SHOULD LIFT TO MVFR BRIEFLY THIS EVENING BEFORE LOWERING AGAIN
LATER TONIGHT AS SHOWERS BECOME MORE NUMEROUS.
OUTLOOK...SUNDAY THROUGH WEDNESDAY...
SUNDAY...HIGH CONFIDENCE. VFR CONDITIONS. W WIND GUSTS UP TO 20-25
KT POSSIBLE. PATCHY FOG POSSIBLE ALONG IMMEDIATE S COAST LATE SUN
NIGHT WITH LOCAL MVFR-IFR VSBYS.
MONDAY...MODERATE CONFIDENCE.
VFR CONDITIONS TO START. MAY SEE SCT SHOWERS/ISOLD TSTMS DURING
MONDAY AFTERNOON/NIGHT WITH LOCAL MVFR-IFR CIGS/VSBYS. PATCHY FOG
LATE MON NIGHT WITH MVFR-IFR VSBYS MAINLY ALONG S COAST.
TUESDAY...LOW TO MODERATE CONFIDENCE...MAINLY FOR TIMING.
BACK DOOR COLD FRONT WILL SHIFT FROM NE TO SW DURING TUE. WINDS
SHIFT FROM LIGHT W TO E-NE FROM E MA WESTWARD. GUSTS UP TO 20-25
KT MAINLY ALONG E COAST. WILL SEE VFR CONDITIONS...BUT MAY SEE
LOWER CLOUDS WITH POCKETS OF FOG AND DRIZZLE ACROSS E MA DURING
TUE AFTERNOON/NIGHT. MVFR-IFR CONDITIONS POSSIBLE. LEFTOVER SCT
SHOWERS/ISOLD THUNDER INTO TUE EVENING...THEN SHIFTS W.
WEDNESDAY...LOW TO MODERATE CONFIDENCE.
WIDELY SCT SHOWERS LINGER ACROSS CT VALLEY TO E SLOPES OF
BERKSHIRES WED...WHILE POCKETS OF MVFR-IFR CIGS/VSBYS POSSIBLY
LINGER ACROSS E COASTAL AREAS WITH ONSHORE WINDS.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH SATURDAY NIGHT/...MODERATE CONFIDENCE.
TONIGHT...NE/SE WINDS BECOME SSW LATER TONIGHT. PATCHY FOG AND
DRIZZLE MAY LOWER VSBY 1-3 MILES WITH A LOW RISK OF DENSE FOG
SOUTH COASTAL WATERS. SHOWERS BECOME MORE WIDESPREAD TOWARD
DAYBREAK.
SATURDAY...WARM FRONT LIFTS NORTH OF THE REGION WITH WINDS
BECOMING SSW 15-20 KT WITH A FEW GUSTS APPROACHING 25 KT NEAR
SHORE. NO SMALL CRAFT ADVISORY AT THE MOMENT AS DURATION AND
FREQUENCY OF 25 KT REMAINS SOMEWHAT UNCERTAIN. ISOLATED-WIDELY
SCATTERED SHOWERS. VERY LOW RISK OF ISOLATED TSTM NEAR SHORE. ANY
MORNING FOG SHOULD BURN OFF BY EARLY AFTERNOON.
SAT NIGHT...COLD FRONT APPROACHES FROM THE WEST WITH SHOWERS
BECOMING MORE WIDESPREAD. VSBY SHOULD BE GOOD GIVEN SW WINDS.
OUTLOOK...SUNDAY THROUGH WEDNESDAY...
MODERATE CONFIDENCE THROUGH PERIOD.
SUNDAY...
HIGH PRES RIDGE BUILDS ACROSS THE WATERS. EXPECT W WINDS 15 KT OR
LESS INTO SUN NIGHT. MAY SEE W GUSTS CLOSE TO 25 KT ON NEARSHORE
WATERS DURING THE AFTERNOON. SEAS SHOULD REMAIN BELOW 5 FT. VSBY
RESTRICTIONS LATE SUN NIGHT POSSIBLE ALONG IMMEDIATE S COASTAL
WATERS.
MONDAY...
FRONT APPROACHES THE WATERS BUT STALLS. S-SW WINDS REMAIN AT 15 KT
OR LESS...THEN DIMINISH INTO MON NIGHT AS BACKDOOR FRONT
APPROACHES. NOTING WIND SHIFT TO N OVER THE EASTERN OUTER WATERS
AFTER MIDNIGHT. COULD SEE SCT SHOWERS/ISOLD THUNDER MON
AFTERNOON/NIGHT WITH FRONT IN VICINITY.
TUESDAY-WEDNESDAY...
BACKDOOR FRONT MOVES SW ACROSS THE WATERS TUE. WINDS SHIFT TO
NE...GUSTING UP TO AROUND 20 KT ON THE OPEN WATERS BEGINNING TUE
AFTERNOON THROUGH WED. EXPECT E-NE SWELLS TO BUILD TO AROUND 5 FT
ON THE OUTER WATERS. SCT SHOWERS/ISOLD THUNDER STILL POSSIBLE INTO
TUE EVENING BUT WILL SHIFT SW AS FRONT PASSES TUE NIGHT.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...NOCERA/EVT
NEAR TERM...NOCERA
SHORT TERM...EVT
LONG TERM...EVT
AVIATION...NOCERA/EVT
MARINE...NOCERA/EVT
AREA FORECAST DISCUSSION
NWS TAUNTON MA
348 PM EDT FRI MAY 9 2014
.SYNOPSIS...
A WARM FRONT WILL APPROACH TONIGHT BRINGING A PERIOD OF SCATTERED
SHOWERS BEFORE IT LIFTS INTO NORTHERN NEW ENGLAND SATURDAY. BEHIND
THE FRONT A WARMER AND MORE HUMID AIRMASS OVERSPREADS THE REGION
SATURDAY. A COLD FRONT WILL MOVE ACROSS THE AREA LATE SATURDAY
NIGHT INTO EARLY SUNDAY MORNING...YIELDING A ROUND OF SCATTERED
SHOWERS. HIGH PRESSURE BUILDS IN FOR MOTHERS DAY. MILD TEMPERATURES
AND UNSETTLED WEATHER ARE ANTICIPATED FOR MOST OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
345 PM UPDATE...
WARM FRONT ACROSS WESTERN PA AND NY WILL APPROACH THE REGION LATER
TONIGHT. BEFORE THEN COOL PREFRONTAL AIRMASS REMAINS OVER SOUTHERN
NEW ENGLAND AS ONSHORE FLOW MAINTAINS COOL MOIST SHALLOW AIRMASS.
WATER VAPOR IMAGERY ALONG WITH MODEL CROSS SECTIONS AND TIME
SECTIONS REVEAL MID LEVEL DRY AIR OVERSPREAD THE REGION AS WELL.
THIS COMBINED WITH MOIST SHALLOW ONSHORE FLOW IS RESULTING IN
AREAS OF DRIZZLE AND FOG ESPECIALLY IN THE CT RVR VLY AND THE
HIGHER TERRAIN /UPSLOPE FLOW/. THIS WILL BECOME MORE WIDESPREAD
THIS EVENING ESPECIALLY WITH SUNSET. THUS NO APPRECIABLE RAINFALL
THIS EVENING. NOT A WASHOUT JUST SPOTTY LIGHT RAIN/DRIZZLE. LAST
SEVERAL RUNS OF THE HRRR SUPPORT THIS THINKING AS WELL.
LATER TONIGHT WARM FRONT ENTERS THE REGION WITH RAIN BECOMING
MORE WIDESPREAD AS MODELS INDICATE MODEST ISENTROPIC LIFT/UPGLIDE
ACROSS THE REGION 06-12Z. MARINGAL INSTABILITY ALOFT TO SUPPORT A
VERY LOW RISK OF AN ISOLATED TSTM WITH LOCALLY BRIEF HEAVY
DOWNPOUR TOWARD SUNRISE. HOWEVER MUCH OF THE ACTIVITY SHOULD BE ON
THE LIGHT SIDE.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
SATURDAY...WARM FRONT LIFTS NORTH OF THE REGION BY MID TO LATE
MORNING WITH WARM SECTOR OVERSPREADING SOUTHERN NEW ENGLAND.
DEFINITELY A BIT OF A SUMMER-ISH FEEL TO THE AIRMASS TOMORROW WITH
MAY SUNSHINE LIFTING TEMPS INTO THE 70S AND DEW PTS IN THE L60S.
AS FOR INSTABILITY DETERMINISTIC AND ENSEMBLE GUIDANCE SUGGEST
ONLY 200-500 J/KG OF MU AND MEAN CAPE TOMORROW AFTERNOON. NOT MUCH
OF A TRIGGER TOMORROW AFTERNOON AS MID LEVEL TROUGH REMAINS WELL
TO THE WEST ALONG WITH ATTENDING COLD FRONT. THUS THINKING AREAL
COVERAGE OF ANY SHOWERS WILL BE ISOLATED TO WIDELY SCATTERED.
GIVEN MU CAPES ARE ONLY 500J/KG OR LESS ALONG WITH MARGINAL WIND
FIELDS ALOFT...ANY TSTMS SHOULD BE ISOLATED AND NON SEVERE. GIVEN
THE HIGHER PWAT AIRMASS CAN`T RULE OUT A BRIEF HEAVY DOWNPOUR.
OTHERWISE A TYPICAL LATE WARM SPRING AFTERNOON WITH ISOLATED-
WIDELY SCATTERED SHOWERS. ANY MORNING FOG WILL BURN OFF BY MIDDAY.
SATURDAY NIGHT...SHOWERS MAY BECOME MORE WIDESPREAD AS COLD FRONT
APPROACHES ALONG WITH POSSIBLE SURFACE WAVE ON THE FRONT. THIS
WOULD RESULT IN SHOWERS MOST NUMEROUS ALONG THE SOUTH COAST. LOW
RISK OF AN ISOLATED TSTM WITH HEAVY RAINFALL. IMPROVING CONDITIONS
TOWARD 12Z SUN FROM WEST TO EAST. GIVEN POST FRONTAL AIRMASS
DOESNT ARRIVE UNTIL SUNDAY IT WILL BE A MILD NIGHT.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGHLIGHTS...
* DRY...WARM WEATHER FOR MOTHERS DAY
* AVERAGE TEMPERATURES AND UNSETTLED WEATHER FOR THE WORK WEEK
MODELS AND CONFIDENCE...
00Z GUIDANCE AGREES THAT A ROCKIES/PLAINS TROUGH WILL BROADEN AS IT
MOVES EWD WITH TIME... YIELDING A MEAN TROUGH COVERING MUCH OF THE
ERN HALF OF THE CONUS/CANADA BY LATE NEXT WEEK. HOWEVER
SIGNIFICANT DIFFERENCES EXIST FOR SOME DETAILS WITHIN THIS
EVOLUTION...CAUSING A LOW CONFIDENCE FORECAST. THE MOST PRONOUNCED
IS A FASTER ADVANCE OF THE INITIAL TROUGH IN RECENT GFS/GEFS RUNS
WITH TRENDS AND OTHER MODELS GENERALLY SUPPORTING SLOWER TIMING.
THEREFORE TRENDED TOWARDS PREVIOUS FORECAST AND WPC. OVERALL HAVE
A MEDIUM CONFIDENCE THAT POP-UP SHOWERS AND ISO THUNDERSTORMS WILL
OCCUR ON MONDAY...BUT A LOW CONFIDENCE BEYOND THAT.
DETAILS...
SUNDAY...
COLD FRONT WILL CROSS THE REGION OVERNIGHT SATURDAY INTO SUNDAY
MORNING. A FEW SCT SHOWERS AND MAYBE AN ISO TSTORM ARE POSSIBLE
ALONG THE FRONT. COLD FRONT SHOULD BE OFFSHORE BY 12Z SUNDAY
ALLOWING FOR SURFACE HIGH PRESSURE TO BUILD IN TO THE AREA FOR
MOTHERS DAY. SUBSIDENCE WILL FILTER IN WITH THE HIGH PRESSURE
ALLOWING FOR DRY WEATHER. FORECAST SOUNDINGS SUGGEST MIXING CLOSE TO
850MB TEMPS WHICH WILL YIELD TO GUSTS NEAR 20-25 MPH. TEMPS COULD
REACH THE UPPER 70S TO LOW 80S AWAY FROM THE COASTS AS 850 MB
TEMPS STAY ABOUT 8C BEHIND THE FRONT. SUNDAY IS THE PICK OF THE
WEEK.
MONDAY AND TUESDAY...
WARM...MOIST AIRMASS IN PLACE ACROSS THE REGION FOR MONDAY AND
TUESDAY. GUIDANCE IS SHOWING A WARM FRONT TRYING TO APPROACH THE
REGION WHICH COULD SPARK SOME SCATTERED SHOWERS AND ISO
THUNDERSTORMS DURING DIURNAL HEATING...ESP ON MONDAY. SURFACE
CAPE VALUES WILL REACH NEAR 1000 J/KG AND WITH SHOWALTERS DROPPING
BELOW 0 HAVE INSERTED THE MENTION FOR THUNDER.
THE EC AND GFS BEGIN TO DIVERGE AT THIS POINT AS THE EC DROPS A BACK
DOOR COLD FRONT ACROSS NEW ENGLAND ON TUESDAY. THE GFS ALSO HINTS AT
THIS BUT IS NOT AS STRONG AS THE EC. BETWEEN THESE 2 FORECAST
GUIDANCE...THERE IS A 20F SURFACE HIGH TEMP DIFFERENCE FOR TUESDAY.
THE CANADIAN AND A FEW MEMBERS OF THE GEFS ALSO DISPLAYS THIS
BACK DOOR FRONT PUSHING ALL THE WAY THROUGH THE AREA...AS WELL AS
WPC. BECAUSE OF THIS TREND HAVE BEGUN CUTTING TEMPS FOR TUESDAY
AND DISPLAYING THE POSSIBILITY OF THE BACK DOOR FRONT. ALTHOUGH IT
MAY BE COOLER THEN FORECASTED...RIGHT NOW JUST SETTLING ON A
TREND.
WEDNESDAY AND BEYOND...
BY WEDNESDAY...A DEEP UPPER TROUGH THAT HAS DUG ACROSS THE CENTRAL
CONUS HAS MOVED EASTWARD OVER THE MIDWEST. THIS TROUGH WILL CONTINUE
TO SLOWLY TRACK EASTWARD DURING THE REST OF THE WEEK. EXPECT SEVERAL
WEAK WAVES TO DEVELOP AHEAD OF THIS TROUGH AND WILL APPROACH THE
AREA DURING THIS TIMEFRAME. AS A RESULT...HAVE CONTINUED TO
MENTION THE POSSIBILITY OF A CHANCE OF POPS FOR SHOWERS/TSTMS FROM
WEDNESDAY THROUGH FRIDAY. MODEL GUIDANCE INDICATES THE TROUGH WILL
SLIDE OFFSHORE BY EITHER FRIDAY OR SATURDAY.
A MILD AIR MASS OVERSPREADS THE REGION WITH SW FLOW AHEAD OF THE
TROUGH. HIGHS WILL GENERALLY TOP OFF IN THE UPPER 60S TO LOW 70S
WITH COOLER CONDITIONS ALONG THE COAST...ESP THE SOUTH COAST DUE TO
SOUTHERLY FLOW.
&&
.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH FRIDAY NIGHT/...LOW CONFIDENCE.
THRU 00Z...LOW CONFIDENCE FORECAST AS TIMING OF IFR CONDITIONS
IMPROVING TO MVFR STILL SOMEWHAT UNCERTAIN. WHERE IFR EXISTS NOW THINK
WE WILL SEE SOME BRIEF IMPROVEMENT TO MVFR AFTER 21Z AS WINDS
SHIFT FROM NE TO SE. ELSEWHERE MVFR SHOULD PREVAIL. AS FOR THE CT
RVR VLY MARGINAL IFR/MVFR WILL CONTINUE. PATCHY FOG AND DRIZZLE
POSSIBLE ALL TERMINALS. ALTHOUGH HEAVY RAIN/THUNDER NOT EXPECTED.
AFTER 00Z...MVFR WILL TREND TO IFR AS THE NIGHT PROGRESSES. PATCHY
FOG AND DRIZZLE POSSIBLE ALL TERMINALS. BETTER CHANCE OF
WIDESPREAD RAIN TOWARD MORNING. VERY LOW RISK OF ISOLATED
THUNDER TOWARD 12Z.
SATURDAY...ANY LEFTOVER IFR IN THE MORNING WILL LIFT TO MVFR OR
EVEN VFR TOWARD MIDDAY AND ESPECIALLY DURING THE AFTERNOON.
ISOLATED-SCATTERED SHOWERS EARLY ACROSS EASTERN MA AND RI. THEN
ANOTHER ROUND OF ISOLATED-SCATTERED SHOWERS DURING THE AFTERNOON
WITH A VERY LOW RISK OF AN ISOLATED TSTM.
SAT NIGHT...SHOWERS SHOULD BECOME MORE NUMEROUS ESPECIALLY ALONG
THE SOUTH COAST. SOME HEAVY RAIN POSSIBLE. AS FOR CIGS/VSBYS ANY
EARLY VFR CONDITIONS QUICKLY LOWER TO MVFR AND EVENTUALLY IFR
OVERNIGHT FROM WEST TO EAST.
KBOS TERMINAL...LOW CONFIDENCE. IFR SHOULD LIMIT BRIEFLY TO MVFR
AFTER 21Z AS WINDS SHIFT FROM NE TO SE AND THEN S. MVFR LOWERS TO
IFR LATER TONIGHT AS SHOWERS BECOME MORE NUMEROUS TOWARD 12Z SAT.
THEN CONDITIONS IMPROVE TO MVFR AND EVENTUALLY VFR SAT AFTERNOON.
ISOLATED-SCATTERED AFTERNOON SHOWERS.
KBDL TERMINAL...LOW CONFIDENCE. IFR CONDITIONS IN THE CT RVR VLY
SHOULD LIFT TO MVFR BRIEFLY THIS EVENING BEFORE LOWERING AGAIN
LATER TONIGHT AS SHOWERS BECOME MORE NUMEROUS.
OUTLOOK...SUNDAY THROUGH TUESDAY...
SUNDAY...MODERATE CONFIDENCE. COLD FRONTAL PASSAGE WILL ALLOW FOR
SCT SHOWERS AND POSSIBLE MVFR CIGS AND VSBYS. THERE IS A LOW PROB
OF A TSRA...WITH OVER THE CAPE AND ISLANDS HAVING THE BEST SHOT
DURING THIS TIMEFRAME. OTHERWISE IMPROVING CONDITIONS FROM WEST TO
EAST ON SUNDAY. GUSTY WINDS UP TO 25 KTS POSSIBLE.
MONDAY-TUESDAY...MODERATE CONFIDENCE.
VFR CONDITIONS TO START. MAY SEE POP-UP SHOWERS AND THUNDERSTORMS
DURING THE DAY DROPPING VSBYS AND CIGS. POSSIBLE BACK DOOR COLD
FRONT ON TUESDAY SWITCHING THE WESTERLY WINDS TO THE EAST ALLOWING
FOR FOG AND DRIZZLE TO ROLL IN.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH SATURDAY NIGHT/...MODERATE CONFIDENCE.
TONIGHT...NE/SE WINDS BECOME SSW LATER TONIGHT. PATCHY FOG AND
DRIZZLE MAY LOWER VSBY 1-3 MILES WITH A LOW RISK OF DENSE FOG
SOUTH COASTAL WATERS. SHOWERS BECOME MORE WIDESPREAD TOWARD
DAYBREAK.
SATURDAY...WARM FRONT LIFTS NORTH OF THE REGION WITH WINDS
BECOMING SSW 15-20 KT WITH A FEW GUSTS APPROACHING 25 KT NEAR
SHORE. NO SMALL CRAFT ADVISORY AT THE MOMENT AS DURATION AND
FREQUENCY OF 25 KT REMAINS SOMEWHAT UNCERTAIN. ISOLATED-WIDELY
SCATTERED SHOWERS. VERY LOW RISK OF ISOLATED TSTM NEAR SHORE. ANY
MORNING FOG SHOULD BURN OFF BY EARLY AFTERNOON.
SAT NIGHT...COLD FRONT APPROACHES FROM THE WEST WITH SHOWERS
BECOMING MORE WIDESPREAD. VSBY SHOULD BE GOOD GIVEN SW WINDS.
OUTLOOK...SUNDAY THROUGH TUESDAY...
MODERATE CONFIDENCE THROUGH PERIOD.
SUNDAY...COLD FRONT WILL PUSH OVER THE WATERS BY SUNDAY MORNING
ALLOW FOR SCT SHOWERS AND SOME ISO THUNDER. SEAS WILL REMAIN AT OR
NEAR 5 FT. SCA MAY STILL BE NEEDED ESP ACROSS NEAR SHORE WATERS ON
SUNDAY AS THE LAND MAY GUST UP TO 25KTS.
MONDAY-TUESDAY...
WARM FRONT WILL APPROACH FROM THE SOUTH ALLOWING FOR SCT SHOWERS
AND ISO THUNDER. BEST CHANCES ARE IN THE BAY AND HARBORS.
OTHERWISE WESTERLY WINDS WILL SHIFT TO THE EAST ON TUESDAY AS BACK
DOOR COLD FRONT MOVES ACROSS THE WATERS.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...NOCERA
NEAR TERM...NOCERA
SHORT TERM...NOCERA
LONG TERM...DUNTEN
AVIATION...NOCERA/DUNTEN
MARINE...NOCERA/DUNTEN
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
920 PM EDT SAT MAY 10 2014
.DISCUSSION...
TONIGHT...EAST/WEST BOUNDARY COLLISION OCCURRING OVER LAKE COUNTY AT
THE PRESENT TIME. ACARS SOUNDING AND LATEST RAP FORECAST SOUNDING
THERE SHOWED THAT LINGERING SUBSIDENCE INVERSION AND LOSS OF DAYTIME
HEATING WOULD LIKELY INHIBIT SHOWER/STORM DEVELOPMENT. HOWEVER...
WILL HOLD OFF REMOVING EVENING POPS UNTIL AFTER THE BOUNDARY
INTERACTION OCCURS AND OTHER ACTIVITY IN WEST CENTRAL FLORIDA
DISSIPATES. OTHERWISE LITTLE CHANGE. CONSIDERABLE MID-HIGH LEVEL
DEBRIS CLOUDINESS EXPECTED FOR MUCH OF THE AREA OVERNIGHT.
SUNDAY (PREVIOUS DISCUSSION)...EXPECT CONSIDERABLE CLOUDINESS ACROSS
THE NORTH TO START THE DAY WHICH SHOULD LIMIT DAYTIME HEATING A BIT
AND HOLD MAX TEMPS TO THE MID AND UPPER 80S ORLANDO NORTHWARD. LOW
LEVEL RIDGE AXIS IS FORECAST TO SHARPEN A BIT ACROSS NORTH FL WHICH
SHOULD BRING A LITTLE DRIER AIR WESTWARD FROM THE ATLC. HAVE DRAWN
ISOLATED (20 PERCENT) POPS ACROSS THE NORTH 2/3 OF FA WHICH WILL BE
CLOSER TO MID LEVEL DISTURBANCE AND KEPT SOUTHERN 1/3 OF FA DRY.
&&
.AVIATION...
MAINLY VFR WITH MID-HIGH LEVEL CLOUDINESS. SEA BREEZE WILL MARCH
INLAND AGAIN ON SUNDAY AND ANY INTERACTION WITH WEST COAST BOUNDARY
SHOULD BE LATE AND OVER WESTERN SECTIONS OF THE PENINSULA...SO NOT
EXPECTING MUCH OF A CHANCE FOR STORMS OVER THE INTERIOR TERMINALS.
&&
.MARINE...
TONIGHT/SUNDAY...LITTLE CHANGE TO THE SOUTHEAST FLOW PATTERN WITH
SURFACE RIDGE AXIS REMAINING NORTH OF THE WATERS. WINDS SHOULD BACK
A LITTLE TO THE EAST/SOUTHEAST ACROSS THE SOUTHERN WATERS BY SUNDAY
AFTERNOON. SPEEDS LOOK CLOSE TO 10 KNOTS ALONG THE COAST EARLY
SUNDAY THEN AROUND 15 KNOTS AS THE AFTERNOON SEA BREEZE KICKS IN.
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
FORECASTS...LASCODY
IMPACT WX...WEITLICH
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
250 PM EDT FRI MAY 9 2014
.SYNOPSIS...
18Z WATER VAPOR AND H4 RAP ANALYSIS CONTINUES TO SHOW AN AMPLIFIED
UPPER LEVEL PATTERN IN PLACE ACROSS THE CONUS. LONGWAVE TROUGHING
SITS OVER THE CENTRAL PLAINS WITH A POTENT SHORTWAVE IMPULSE
PIVOTING NORTHWARD OVER THE UPPER MS VALLEY/WESTERN GREAT LAKES. THE
DOWNSTREAM FLOW THEN RIDGES UP OVER THE EASTERN SEABOARD EXTENDING
FROM THE EASTERN GULF/FLORIDA PENINSULA TO QUEBEC. WV IMAGERY SHOWS
A BIT MORE UPPER LEVEL MOISTURE HAS WORKED OVERHEAD COMPARED TO
PREVIOUS DAYS...AND THIS WILL COME IN THE FORM OF PERIODIC CIRRUS.
THIS HIGH LEVEL MOISTURE IS SHOWN ON THE 12Z KTBW SOUNDING ABOVE
400MB...HOWEVER BELOW THIS LEVEL...THE SUPPRESSION FROM THE UPPER
RIDGE CONTINUES TO SUPPLY US WITH A DRY COLUMN THROUGH A MAJORITY OF
THE TROP.
AT THE SURFACE...RIDGE OF HIGH PRESSURE CENTERED OVER THE WESTERN
ATLANTIC CONTINUES TO RIDGE BACK TO THE WEST WITH AN AXIS NEAR THE
I-10 CORRIDOR. OUR POSITION TO THE SOUTH OF THIS RIDGE AXIS IS
PROVIDING A LIGHT SOUTHEAST SYNOPTIC FLOW TO THE REGION.
HOWEVER...AT THE COAST WINDS HAVE SHIFTED ONSHORE WITH THE
DEVELOPMENT OF THE AFTERNOON SEA-BREEZE. TEMPERATURES ARE IN THE
UPPER 80S TO LOWER 90S ACROSS THE INTERIOR AND IN THE LOWER TO
MIDDLE 80S AT THE BEACHES. EARLY SHALLOW CU FIELD THAT WAS TRYING TO
DEVELOP HAS NOW ESSENTIALLY DISSIPATED AS THE BOUNDARY LAYER HAS
MIXED UP INTO THE SIGNIFICANTLY DRIER AIR ALOFT. EXPECT MOSTLY SUNNY
SKIES TO NOW PREVAIL FOR THE REMAINDER OF THE DAYLIGHT HOURS.
.SHORT TERM (TONIGHT THROUGH SATURDAY)...
TONIGHT...
SHORTWAVE ENERGY RIDING NORTHWARD FROM THE WESTERN GULF OF MEXICO TO
THE FLORIDA PANHANDLE/GEORGIA VICINITY WILL DE-AMPLIFY THE UPPER
RIDGE AND BEGIN TO SHIFT ITS AXIS SOUTH AND SOUTHEAST. BY MORNING
THE UPPER RIDGE AXIS WILL BE DOWN OVER SOUTH FLORIDA. THE SURFACE
RIDGE WILL REMAIN IN PLACE WITH A LIGHT SOUTHEAST FLOW OVER THE
AREA. THIS FLOW LOOKS TO REMAIN STRONG ENOUGH (ESPECIALLY JUST ABOVE
THE SURFACE) TO SUPPRESS ANY SIGNIFICANT FOG DEVELOPMENT. THIS IS
SHOWN IN THE SREF VISIBILITY PROBS OVERNIGHT WHICH ARE UNDER 10% FOR
VIS < 3 MILES. A MILD NIGHT UPCOMING WITH LOWS GENERALLY IN THE
UPPER 60S TO LOWER 70S. SHOULD GET DOWN INTO THE MIDDLE 60S FOR
INLAND LEVY COUNTY. NORMALLY WARMER SPOTS ALONG THE COAST SUCH AS ST
PETE WILL HOLD IN THE MIDDLE 70S.
SATURDAY...
A DECENT DAY IN TERMS OF SENSIBLE WEATHER ON TAP TO START OUT THE
WEEKEND. UPPER RIDGE AXIS WILL HAVE SHIFTED SOUTH OF THE AREA...SO A
LITTLE LESS SYNOPTIC SUPPRESSION AND HENCE THE COLUMN WILL BE ABLE
TO BEGIN MOISTENING THROUGH A GREATER DEPTH. SATURDAY LOOKS TO HAVE
A MIX OF SUN AND CLOUDS IN THE MORNING DUE TO PASSING HIGHER LEVEL
CIRRUS...AND THEN DUE TO A SCT-BKN CUMULUS FIELD DEVELOPING IN THE
LATE MORNING AND AFTERNOON. OVERALL THE COLUMN IS STILL FAIRLY
HOSTILE TO DEEP CONVECTION DUE TO ENTRAINMENT OF DRY
AIR...HOWEVER...NOT QUITE AS HOSTILE AS TODAY AND THE PAST COUPLE OF
DAYS. THEREFORE...AS THE SEA-BREEZE MOVES INLAND...THE LOW LEVEL
FOCUS WILL HAVE A SLIGHTLY BETTER CHANCE OF KICKING OFF A FEW WIDELY
SCT SHOWERS DURING THE MIDDLE TO LATE AFTERNOON. MOST OF THE HIRES
CONVECTION ALLOWING GUIDANCE ARE SHOWING A LEAST THIS ISOLATED
SHOWER VARIETY...BUT WITH BRIEF LIFE CYCLES DUE TO THE STILL FAIRLY
DRY AIR ALOFT. GRIDS/FORECAST WILL SHOW A 20-30% CHANCE OF THESE
LATE DAY SHOWERS...GENERALLY OVER THE INTERIOR...INLAND FROM THE
I-75 CORRIDOR. TEMPERATURES SHOULD BE SIMILAR WITH WIDESPREAD UPPER
80S INLAND AND LOWER TO MIDDLE 80S AT THE BEACHES. ENJOY THE WEEKEND
EVERYONE!
&&
.MID TERM (SUNDAY)...
HIGH PRESSURE WILL REMAIN THE DOMINANT WEATHER FEATURE FOR THE
SECOND HALF OF THE WEEKEND. THE EAST/WEST COAST SEA BREEZES
SHOULD BE ENOUGH TO SPARK ISOLATED TO WIDELY SCATTERED SHOWERS AND
THUNDERSTORMS DURING THE AFTERNOON...SO WILL INCLUDE SLIGHT
CHANCE/LOW CHANCE POPS IN THE FORECAST FOR MOST LOCATIONS. HIGH
TEMPERATURES WILL GENERALLY TOP OUT IN THE UPPER 80S TO LOWER
90S...WITH LOWS RANGING FROM THE MID TO UPPER 60S ACROSS THE
INTERIOR COOL SPOTS TO THE LOWER 70S ALONG THE COAST.
&&
.LONG TERM (SUNDAY NIGHT-FRIDAY)...
MEDIUM RANGE GUIDANCE IS IN GOOD AGREEMENT THROUGH EARLY NEXT
WEEK...WITH SOLUTIONS THEN DEVIATING WITH RESPECT TO THE HANDLING
OF AN EASTERLY WAVE DURING THE MIDDLE TO LATTER PORTION OF NEXT
WEEK. WILL FOLLOW A BLENDED APPROACH TO THE FORECAST GIVEN THE
UNCERTAINTY...AND THIS WILL RESULT IN CHANCES FOR MAINLY
AFTERNOON/EVENING SHOWERS AND THUNDERSTORMS EACH DAY THROUGH THE
LONG TERM PERIOD. AT THIS POINT...IT APPEARS THAT THE HIGHEST
PROBABILITIES FOR RAINFALL WILL FALL IN THE WEDNESDAY/THURSDAY
TIME FRAME WHEN THE DEEPEST MOISTURE WILL BE IN PLACE.
TEMPERATURES ARE EXPECTED TO RUN CLOSE TO NORMAL THROUGH THE LONG
TERM PERIODS.
&&
.AVIATION...
VFR CONDITIONS WILL PREVAIL THROUGH THE REST OF THE AFTERNOON AND
EVENING. SOUTHEAST FLOW OVERNIGHT LOOKS TO REMAIN ELEVATED ENOUGH TO
PREVENT MUCH IN THE WAY OF FOG DEVELOPMENT. NOT OUT OF THE QUESTION
TO SEE A BRIEF MVFR PERIOD AT KLAL OR KPGD TOWARD SUNRISE ON
SATURDAY...HOWEVER AT THIS TIME CONFIDENCE OF REDUCED VISIBILITIES
AT EITHER TERMINAL ARE LOW ENOUGH TO KEEP MENTION OUT OF THE TAFS.
&&
.MARINE...
WINDS WILL SHIFT BACK TO THE SOUTHEAST OVERNIGHT AND BECOME
BREEZY ONCE AGAIN...HOWEVER AT THIS TIME IT DOES NOT APPEAR AS
THROUGH CAUTIONARY LEVEL WINDS OF 15-20 KNOTS WILL BE REACHED FOR
THE MAJORITY OF THE FORECAST WATERS. WILL INCLUDE A MENTION OF
EXERCISE CAUTION FOR ONLY THE WATERS OFF CHARLOTTE AND LEE COUNTIES
WHERE THE BEST SETUP FOR THE NOCTURNAL WIND SURGE WILL EXIST. THIS
CONTINUED PATTERN OF ONSHORE AFTERNOON WINDS AND OFFSHORE SLIGHTLY
STRONGER FLOW AT NIGHT AND DURING THE EARLY MORNING HOURS WILL
CONTINUE THROUGH THE UPCOMING WEEKEND AS HIGH PRESSURE REMAINS
PARKED TO THE NORTH OF THE FORECAST WATERS.
&&
.FIRE WEATHER...
LOW LEVEL MOISTURE WILL INCREASE FURTHER INTO THE WEEKEND
PREVENTING RELATIVE HUMIDITY FROM REACHING CRITICAL LEVELS EITHER
SATURDAY OR SUNDAY. THERE WILL BE BETTER CHANCES FOR A FEW AFTERNOON
STORMS ALONG THE SEA-BREEZE THIS WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 73 89 73 89 / 0 10 0 20
FMY 72 91 71 91 / 0 10 10 20
GIF 70 90 71 91 / 0 30 20 20
SRQ 71 89 71 88 / 0 10 10 10
BKV 67 90 66 90 / 10 10 10 20
SPG 74 88 74 88 / 0 10 10 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/AVIATION/MARINE/FIRE WEATHER...MROCZKA
MID TERM/LONG TERM...JELSEMA
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
1123 AM EDT Fri May 9 2014
.Near Term [This Afternoon Through Tonight]...
There is higher than normal uncertainty in the forecast from late
this afternoon into tonight. Model guidance continues to indicate
an area of heavy rainfall somewhere along the northern Gulf coast
in that time period - with a sharp cutoff on the eastern extent.
In other words, the models all generally agree that there will be
a considerable gradient in rainfall somewhere in the vicinity of
the western border of our forecast area. However, there is some
variation in the exact placement of this gradient on the order of
about 50-70 miles which makes a huge difference in impacts for our
area. In general, global models have kept much of the rain west of
our area through 12Z Saturday while a fair number of 4km WRF runs
push the heavy rain into far western parts of our area (generally
along and west of a PAM-DHN line).
Models seem to be struggling to initialize a well-defined outflow
boundary and other mesoscale features across western Alabama and
Mississippi. When compared with recent objective analysis, the
models seem to be placing these features a bit too far west. This
argues that the surface and boundary layer foci for additional
convective development this afternoon will be situated a bit
closer to our local area. However, the large scale forcing
mechanisms - including the LLJ and favored RFQ of the upper level
jet streak - continue to be further west closer to what the
models are portraying. Therefore, there is some uncertainty as to
how to correct for the misplacement of these mesoscale features in
the models, as large scale forcing mechanisms seem to be modeled
fairly well. It may not be a simple linear adjustment (shifting
the model QPF east 50 miles or so), given the lagging UVV aloft.
The 14Z RAP analysis suggested that the boundary layer behind the
outflow boundary over much of MS and W AL had been convectively
overturned with MUCAPE less than 250 j/kg. Therefore, it seems
that most of the new convective development would be focused in
the warm, moist air mass just ahead of the outflow boundary this
afternoon - or just west of our area. There is some evidence of
this happening already on radar mosaics. This may put heavy rain
and thunderstorms in a better position to push into our area
tonight. However, given the high level of uncertainty, and only a
handful of convection-allowing models showing high QPF in our
area, we have opted not to issue a Flash Flood Watch at this time.
We did bump up PoPs and QPF in the far western parts of our
forecast area with this update, and will re-evaluate a watch this
afternoon after new model guidance arrives.
&&
.Hydrology...
The only rivers that remain above flood stage at this time are the
Choctawhatchee River at Bruce and several sites along the Suwannee
River and stages are falling at all these locations. There is a
chance of some heavy rainfall tonight and early Saturday in the
far western part of our area - mainly in the Choctawhatchee
drainage basin (which includes some smaller streams and rivers).
There remains considerable uncertainty as to whether this will
occur, but given high soil moisture levels it would not take much
rainfall to create flooding problems in those areas.
The most up-to-date river forecast information can always be found
on our AHPS page (below).
http:/water.weather.gov/ahps2/index.php?wfo=tae
&&
.Prev Discussion [304 AM EDT]...
.Short Term [Saturday Through Sunday]...
The upper ridge will be temporarily shunted southeast of the area
from tonight through Saturday with heights building once again on
Sunday as another upstream trough amplifies across the Rockies.
The surface high will remain in place across the region. The ridge
will keep any synoptic scale systems from approaching the area.
However, increasing moisture and instability will contribute to a
gradual upward trend in PoPs into Saturday. After that, the deep
layer ridging will re-assert itself with PoPs lowering, at least
across our western zones. Rainfall totals are not expected to be
high enough for any flooding concerns. Increased clouds and
showers will keep daytime temps a bit lower than recent days with
somewhat hotter temps returning for Sunday. Min temps will remain
in the 60s.
.Long Term [Sunday Night Through Friday]...
While no systems of any real significance are expected to impact our
CWA until perhaps the very end of the period as the next deepening
upper level trough approaches from the west, there are still some
discrepancies yet to be resolved in the Global models for the
beginning of the period. If the GFS is correct, the next shortwave
will swing rapidly through the region by this Saturday night with
generally fair and warm weather for the bulk of the period as zonal
flow gradually transitions into upper level ridging. The ECMWF, on
the other hand, keeps conditions a bit more unsettled on Sunday and
Monday, as it attempts to cutoff a weak upper level low over the
northern Gulf coast. However, should this even occur, it will do so
under rising heights, so while this may make for a somewhat
unsettled end to the upcoming weekend, only sct showers and storms
would likely be the end result, and certainly not significant enough
to cancel outdoor plans.
.Aviation...
[Through 06Z Saturday] MVFR restrictions in a fog/ceiling mix may
be possible briefly this morning at ECP, TLH, and VLD. Otherwise,
VFR will prevail today under a scattered to broken mid and high
level clouds deck. Southerly winds may be gusty at times to around
20 knots.
.Marine...
High pressure will continue to ridge from the Atlantic westward
across the Gulf Coast states through the period. This will maintain
onshore winds across the waters, primarily out of the southeast.
Wind speeds are expected to remain below headline criteria. A front
will approach from the northwest on Tuesday.
.Fire Weather...
Moisture and rain chances will be increasing over the next few days
and hazardous fire weather conditions are not anticipated.
Dispersions will likely be rather high this afternoon.
&&
.Preliminary Point Temps/PoPs...
Tallahassee 89 66 87 63 89 / 0 10 20 10 20
Panama City 84 70 81 69 84 / 10 50 30 20 20
Dothan 89 66 84 65 89 / 10 30 40 20 30
Albany 90 67 85 64 90 / 0 20 40 20 30
Valdosta 93 66 89 63 92 / 0 10 20 10 30
Cross City 90 66 87 64 88 / 0 10 10 10 30
Apalachicola 82 69 81 68 82 / 0 30 20 10 20
&&
.TAE Watches/Warnings/Advisories...
FL...High Rip Current Risk through this evening for Coastal Bay-
Coastal Franklin-South Walton.
GA...None.
AL...None.
GM...None.
&&
$$
NEAR TERM...LAMERS
SHORT TERM...WOOL
LONG TERM...GOULD
AVIATION...HARRIGAN
MARINE...WOOL
FIRE WEATHER...HARRIGAN
HYDROLOGY...LAMERS
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
910 AM EDT FRI MAY 9 2014
.UPDATE (REST OF TODAY AND TONIGHT)...
13Z WATER VAPOR AND H4 RAP ANALYSIS CONTINUES TO SHOW AN AMPLIFIED
UPPER LEVEL PATTERN IN PLACE ACROSS THE CONUS. LONGWAVE TROUGHING
SITS OVER THE CENTRAL PLAINS WITH A POTENT SHORTWAVE IMPULSE
PIVOTING NORTHWARD OVER THE UPPER MS VALLEY/WESTERN GREAT LAKES. THE
DOWNSTREAM FLOW THEN RIDGES UP OVER THE EASTERN SEABOARD EXTENDING
FROM THE EASTERN GULF/FLORIDA PENINSULA TO QUEBEC. THIS RIDGE WILL
REMAIN PARKED OVER OUR LOCAL AREA FOR ONE MORE DAY PROVIDING WARM
AND MOSTLY DRY CONDITIONS. WV IMAGERY SHOWS A BIT MORE UPPER LEVEL
MOISTURE HAS WORKED OVERHEAD COMPARED TO PREVIOUS DAYS...AND THIS
WILL COME IN THE FORM OF PERIODIC CIRRUS. THIS HIGH LEVEL MOISTURE
IS SHOWN ON THE 12Z KTBW SOUNDING ABOVE 400MB...HOWEVER BELOW THIS
LEVEL...THE SUPPRESSION FROM THE UPPER RIDGE CONTINUES TO SUPPLY US
WITH A DRY COLUMN THROUGH A MAJORITY OF THE TROP. A STRONG
SUBSIDENCE INVERSION IS ALSO SEEN IN THE SOUNDING PROFILE AROUND
900MB. THERE ARE ACTUALLY SOME DECENT LAPSE RATES IN THE LOWER
LEVELS ABOVE THIS INVERSION...HOWEVER THE DEPTH OF THE DRY AIR AND
THE OVERALL SUPPRESSION SHOULD KEEP ANY SEA-BREEZE SHOWERS VERY
LIMITED.
AT THE SURFACE...RIDGE OF HIGH PRESSURE CENTERED OVER THE WESTERN
ATLANTIC CONTINUES TO RIDGE BACK TO THE WEST WITH AN AXIS NEAR THE
I-10 CORRIDOR. OUR POSITION TO THE SOUTH OF THIS RIDGE AXIS IS
PROVIDING A LIGHT SOUTHEAST FLOW TO THE REGION.
REST OF TODAY...
MOSTLY SUNNY SKIES TO START THE MORNING OFF AT MOST LOCATIONS. THE
NEAR 100% INSOLATION WILL ALLOW TEMPERATURES TO WARM QUICKLY INTO
THE 80S...ON THEIR WAY TO AFTERNOON HIGHS IN THE UPPER 80S TO LOWER
90S ACROSS THE INTERIOR AND LOWER/MIDDLE 80S CLOSER TO THE COAST.
WILL SEE ENOUGH TERRESTRIAL HEATING TO FORCE A SEA-BREEZE THIS
AFTERNOON...HOWEVER THE SOUTHEAST FLOW JUST ABOVE THE SURFACE IS 15+
KNOTS PER MODEL AND CONFIRMED BY KTBW SOUNDING. THIS FLOW WOULD BE
ENOUGH TO PIN ANY SEA-BREEZE TO THE COAST (OR EVEN KEEP IT JUST
OFFSHORE). HOWEVER...NAM/LOCAL HIRES WRFARW GUIDANCE BOTH SHOWING
THIS FLOW RELAXING SOMEWHAT FOR THE AFTERNOON...SO WILL SHOW THE
SEA-BREEZE MAKING SOME INLAND PROGRESS...IT JUST MAY BE LATER
ARRIVING THAN DURING PREVIOUS DAYS.
THE OPPOSING FLOW WILL ADD SOME LOW LEVEL CONVERGENCE/FOCUS ALONG
THIS SEA-BREEZE BOUNDARY. CAN NOT RULE OUT A FEW ISOLATED/BRIEF
SHOWERS AFTER 3-4PM...HOWEVER...WITH THE RIDGE ALOFT...UPDRAFTS ARE
GOING TO STRUGGLE ABOVE 10-12KT...AND ANY CUMULUS TOWERS WILL BE
FIGHTING SIGNIFICANT DRY AIR INTRUSION. FOR NOW WILL LEAVE MENTION
OF SHOWERS OUT OF THE FORECAST AS RAIN CHANCES ARE REALLY 10% OR
LESS FOR ANY PARTICULAR SPOT. HOWEVER...WILL NOT BE SURPRISED TO SEE
A SHOWER OR 2 POP UP ON RADAR LATER TODAY. LIKELY TO DISAPPEAR FROM
RADAR AS QUICKLY AS THEY APPEAR THOUGH.
TONIGHT...
SHORTWAVE ENERGY RIDING NORTHWARD FROM THE WESTERN GULF OF MEXICO TO
THE FLORIDA PANHANDLE/GEORGIA VICINITY WILL DE-AMPLIFY THE UPPER
RIDGE AND BEGIN TO SHIFT ITS AXIS SOUTH AND SOUTHEAST. BY MORNING
THE UPPER RIDGE AXIS WILL BE DOWN OVER SOUTH FLORIDA. THE SURFACE
RIDGE WILL REMAIN IN PLACE WITH A LIGHT SOUTHEAST FLOW OVER THE
AREA. THIS FLOW LOOKS TO REMAIN STRONG ENOUGH (ESPECIALLY JUST ABOVE
THE SURFACE) TO SUPPRESS ANY SIGNIFICANT FOG DEVELOPMENT. THIS IS
SHOWN IN THE SREF VISIBILITY PROBS OVERNIGHT WHICH ARE UNDER 10% FOR
VIS < 3 MILES. A MILD NIGHT UPCOMING WITH LOWS GENERALLY IN THE
UPPER 60S TO LOWER 70S. SHOULD GET DOWN INTO THE MIDDLE 60S FOR
INLAND LEVY COUNTY. NORMALLY WARMER SPOTS ALONG THE COAST SUCH AS
ST PETE WILL HOLD IN THE MIDDLE 70S. HAVE A GREAT FRIDAY EVERYONE!
&&
.MID TERM (SATURDAY-SUNDAY)...
HIGH PRESSURE WILL REMAIN THE DOMINANT WEATHER FEATURE THROUGH THE
PERIOD. THE EAST/WEST COAST SEA BREEZES SHOULD BE ENOUGH TO SPARK
ISOLATED TO WIDELY SCATTERED SHOWERS AND THUNDERSTORMS EACH
AFTERNOON...SO WILL INCLUDE SLIGHT CHANCE/LOW CHANCE POPS IN THE
FORECAST IN MOST LOCATIONS. HIGH TEMPERATURES WILL GENERALLY TOP OUT
IN THE UPPER 80S TO LOWER 90S BOTH DAYS...WITH LOWS SATURDAY NIGHT
RANGING FROM THE MID TO UPPER 60S ACROSS THE INTERIOR COOL SPOTS TO
THE LOWER 70S ALONG THE COAST.
&&
.LONG TERM (SUNDAY NIGHT-FRIDAY)...
MEDIUM RANGE GUIDANCE IS IN GOOD AGREEMENT THROUGH EARLY NEXT
WEEK...WITH SOLUTIONS THEN DEVIATING WITH RESPECT TO THE HANDLING
OF AN EASTERLY WAVE DURING THE MIDDLE TO LATTER PORTION OF NEXT
WEEK. WILL FOLLOW A BLENDED APPROACH TO THE FORECAST GIVEN THE
UNCERTAINTY...AND THIS WILL RESULT IN CHANCES FOR MAINLY
AFTERNOON/EVENING SHOWERS AND THUNDERSTORMS EACH DAY THROUGH THE
LONG TERM PERIOD. AT THIS POINT...IT APPEARS THAT THE HIGHEST
PROBABILITIES FOR RAINFALL WILL FALL IN THE WEDNESDAY/THURSDAY
TIME FRAME WHEN THE DEEPEST MOISTURE WILL BE IN PLACE.
TEMPERATURES ARE EXPECTED TO RUN CLOSE TO NORMAL THROUGH THE LONG
TERM PERIODS.
&&
.AVIATION...
VFR CONDITIONS WILL PREVAIL THROUGH THE REST OF THE DAY AND EVENING.
EXPECT A FEW-SCT CU FIELD TO DEVELOP DURING THE AFTERNOON WITH BASES
BETWEEN 4-6KFT. SOUTHEAST FLOW OVERNIGHT LOOKS TO REMAIN ELEVATED
ENOUGH TO PREVENT MUCH IN THE WAY OF FOG DEVELOPMENT. NOT OUT OF THE
QUESTION TO SEE A BRIEF MVFR PERIOD AT KLAL OR KPGD TOWARD SUNRISE
ON SATURDAY...HOWEVER AT THIS TIME CONFIDENCE OF REDUCED
VISIBILITIES AT EITHER TERMINAL ARE LOW ENOUGH TO KEEP MENTION OUT
OF THE TAFS.
&&
.MARINE...
BREEZY CONDITIONS OVER THE COASTAL WATERS WILL SETTLE DOWN LATER
THIS MORNING WITH WINDS TURNING ONSHORE NEAR THE COAST DURING THE
EARLY TO MID AFTERNOON. WINDS WILL SHIFT BACK TO THE SOUTHEAST
OVERNIGHT AND BECOME BREEZY ONCE AGAIN...HOWEVER AT THIS TIME IT
DOES NOT APPEAR AS THROUGH CAUTIONARY LEVEL WINDS OF 15-20 KNOTS
WILL BE REACHED. THIS CONTINUED PATTERN OF ONSHORE AFTERNOON WINDS
AND OFFSHORE SLIGHTLY STRONGER FLOW AT NIGHT AND DURING THE EARLY
MORNING HOURS WILL CONTINUE THROUGH THE UPCOMING WEEKEND AS HIGH
PRESSURE REMAINS PARKED TO THE NORTH OF THE FORECAST WATERS.
&&
.FIRE WEATHER...
RELATIVE HUMIDITY WILL BRIEFLY APPROACH CRITICAL LEVELS DURING THE
MID/LATE AFTERNOON AWAY FROM THE COAST. IN ADDITION...EFFICIENT
TRANSPORT WINDS AND GOOD DIURNAL MIXING WILL RESULT IN HIGH
DISPERSION INDICES THIS AFTERNOON AWAY FROM THE COAST AS WELL. LOW
LEVEL MOISTURE WILL INCREASE FURTHER INTO THE WEEKEND PREVENTING
RELATIVE HUMIDITY FROM REACHING CRITICAL LEVELS EITHER SATURDAY OR
SUNDAY. THERE WILL BE BETTER CHANCES FOR A FEW AFTERNOON STORMS
ALONG THE SEA-BREEZE THIS WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 90 72 88 73 / 0 0 10 0
FMY 92 70 91 71 / 0 0 20 10
GIF 90 70 90 71 / 0 0 20 20
SRQ 87 70 87 71 / 0 0 10 10
BKV 91 65 89 66 / 10 10 10 10
SPG 89 74 88 74 / 0 0 10 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
UPDATE/AVIATION/MARINE/FIRE WEATHER...MROCZKA
MID TERM/LONG TERM...JELSEMA
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
605 PM EDT FRI MAY 9 2014
.SYNOPSIS...
HIGH PRESSURE RIDGING INTO THE FORECAST AREA FROM THE ATLANTIC
WILL WEAKEN SATURDAY AS A DISSIPATING FRONTAL SYSTEM MOVES INTO
THE AREA. HIGH PRESSURE REGAINS CONTROL FOR THE BEGINNING OF NEXT
WEEK. ANOTHER FRONT IS EXPECTED TO AFFECT THE REGION LATE NEXT
WEEK.
&&
.NEAR TERM /THROUGH SATURDAY/...
HEADING INTO THIS EVENING...THE SURFACE RIDGE WILL CONTINUE TO
EXTEND INTO THE FORECAST AREA FROM THE ATLANTIC. SATELLITE TRENDS
SHOW CONSIDERABLE MID AND UPPER CLOUDINESS MOVING ACROSS THE
REGION EARLY THIS EVENING. A WEAK MID-LEVEL SHORTWAVE TROUGH...A
LITTLE LOW-LEVEL CONVERGENCE ASSOCIATED WITH A WEAK LEE-SIDE
TROUGH PLUS DAYTIME HEATING HAS PRODUCED A FEW LIGHT SHOWERS
ACROSS THE WRN MIDLANDS/NRN CSRA. MAIN AREA OF
SHOWERS/THUNDERSTORMS REMAIN WELL WEST OF THE AREA CLOSER TO THE
COLD FRONT ACROSS WESTERN NC INTO NRN GA. WILL CONTINUE WITH A
MENTION OF A SLIGHT CHANCE OF A SHOWER/ISO THUNDER THROUGH THE
EVENING HOURS.
OVERNIGHT...THE MODELS INDICATE AN INCREASE IN MOISTURE...BUT THE
DEEPER MOISTURE REMAINS WEST OF THE AREA. THERE MAY BE AN INCREASE
IN INSTABILITY ASSOCIATED WITH A MID-LEVEL SHORTWAVE TROUGH.
HOWEVER...MOISTURE SHOULD REMAIN LIMITED AND ANY CONVERGENCE
ASSOCIATED WITH A LEE-SIDE TROUGH SHOULD BE WEAK. THE SHOWER OR
THUNDERSTORM CHANCE IS LOW. THE NAM AND GFS MOS HAVE POPS LESS
THAN 20 PERCENT.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
THE MODELS INDICATE MOISTURE SATURDAY ASSOCIATED WITH THE
REMNANTS OF A COLD FRONT. PRECIPITABLE WATER IS FORECAST TO
INCREASE TO AROUND 1.5 INCHES WITH WEAK LIFT AHEAD OF THE BROAD
UPPER-LEVEL TROUGH. THERE SHOULD ALSO BE LITTLE LOW-LEVEL
CONVERGENCE ASSOCIATED WITH A WEAK LEE-SIDE TROUGH. KEPT CHANCE
POPS SATURDAY. THE GUIDANCE CONSENSUS SUPPORTS POPS AROUND 30
PERCENT.
THUNDERSTORMS MAY LINGER SATURDAY EVENING ASSOCIATED WITH CONVERGENCE
INTO THE WEAK LEE-SIDE TROUGH AND BAND OF MOISTURE FROM THE
REMNANTS OF THE FRONT PLUS HEATING. THE MODELS ARE CONSISTENT
SHIFTING DIMINISHING MOISTURE EAST SATURDAY NIGHT WITH H5 HEIGHTS
BUILDING. THE MODELS SHOW THE RIDGE REMAINING DOMINATE THROUGH
SUNDAY NIGHT WITH LITTLE MOISTURE. THE NAM AND GFS MOS SUPPORT
POPS LESS THAN 20 PERCENT LATE SATURDAY NIGHT THROUGH SUNDAY
NIGHT. USED THE WARMER TEMPERATURE GUIDANCE BECAUSE OF RECENT
VERIFICATION...UPPER RIDGING...AND THE DRY ENVIRONMENTAL CONDITIONS.
THE LOW TEMPERATURE GUIDANCE WAS CLOSE.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
MODELS ARE IN RELATIVELY GOOD AGREEMENT EARLY IN THE PERIOD BUT
THEN BEGIN TO DIFFER LATER IN THE WEEK. THE GFS MOVES THE UPPER
LEVEL TROF AND SFC CDFNT OUT EARLIER WHILE THE ECMWF IS SLOWER BY
24HRS. AS A RESULT CHANCES OF RAIN AND TEMPS ARE DIFFERENT. HAVE
TAKEN AN AVERAGE OF THE MOS GUIDANCE FOR EACH MODEL DAYS 5 THRU 7.
MODELS DO KEEP IT DRY EARLY IN THE WEEK THEN THE NEXT CHANCE OF
PRECIP WILL BE LATE IN THE PERIOD WHICH IS WHERE THE TIMING ISSUES
COME IN. MAX TEMPERATURES WILL BE AROUND 90 MONDAY AND TUESDAY
WITH UPPER 80S WEDNESDAY COOLING INTO THE UPPER 70S TO LOWER 80S
THURSDAY AND FRIDAY. OVERNIGHT LOWS WILL BE IN THE 60S MONDAY
THROUGH THURSDAY AND IN THE 50S FRIDAY.
&&
.AVIATION /22Z FRIDAY THROUGH WEDNESDAY/...
HIGH-LEVEL CLOUDS WILL CONTINUE TO STREAM ACROSS THE TAF SITES
THROUGH THE PERIOD IN THE SOUTHWEST FLOW ALOFT. CONVERGENCE
ASSOCIATED WITH A WEAK LEE-SIDE TROUGH PLUS MID-LEVEL SHORTWAVE
TROUGH COULD HELP SUPPORT THUNDERSTORMS BUT THE CHANCE IS LOW
BECAUSE OF SHALLOW MOISTURE AND WEAK FORCING. THE HRRR INDICATES
JUST ISOLATED COVERAGE LATE THIS AFTERNOON AND THE CHANCE IS MUCH
TOO LOW TO INCLUDE IN THE TERMINAL FORECASTS AT THIS TIME. MIXING
HAS RESULTED IN WIND GUSTS AROUND 20 KNOTS THIS AFTERNOON.
DIMINISHED MIXING BEGINNING AROUND SUNSET SHOULD RESULT IN LESS
WIND. CLOUDINESS AND A LITTLE MIXING SHOULD LIMIT FOG DURING THE
EARLY MORNING HOURS SATURDAY. THE GFS AND NAM MOS INDICATE VFR
CONDITIONS.
.EXTENDED AVIATION OUTLOOK...NO SIGNIFICANT IMPACTS EXPECTED
THROUGH TUESDAY.
&&
.CLIMATE...
TODAY MARKS THE 5TH DAY IN A ROW OF 90 DEGREES OR HIGHER AT BOTH
AUGUSTA BUSH FIELD AND COLUMBIA METRO. THIS IS NOT A RECORD. AT
AUGUSTA...THE RECORD FOR THE MONTH OF MAY IS 13 CONSECUTIVE DAYS
IN 1998 AND 1965. AT COLUMBIA...THE RECORD FOR THE MONTH OF MAY
IS 13 CONSECUTIVE DAYS IN 1962. TEMPERATURES ARE EXPECTED TO NOT
REACH 90 DEGREES SATURDAY WITH AFTERNOON HIGHS IN THE MID/UPPER
80S EXPECTED.
AGS...
5TH...92
6TH...91
7TH...91
8TH...91
9TH...90
CAE...
5TH...95 TIED THE RECORD HIGH OF 95 SET IN 2012 AND 1955
6TH...93
7TH...94
8TH...95
9TH...93
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
77
AREA FORECAST DISCUSSION
NWS PEACHTREE CITY GA
315 PM EDT FRI MAY 9 2014
SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/...
MOIST SW FLOW ALOFT HAS MOVED OVER THE FORECAST AREA WITH THE
DEEPEST MOISTURE OVER N AND PORTIONS OF CENTRAL GA WITH AN UPPER
SHORT WAVE IN THE FLOW. GFS AND NAM ARE INCONSISTENT WITH HOW FAR
SE TO TAKE THE DEEP MOISTURE WITH THE GFS MUCH MORE AGGRESSIVE
MOVING THE MOISTURE TO THE SE. HI-RES REFLECTIVITY FORECASTS FROM
THE WRF AND HRRR WEAKEN THE LINE OF SHOWERS AND STORMS OVER NW GA
EARLY THIS EVENING AND WITH ONLY WEAK INSTABILITY OVER N GA...THIS
SEEMS REASONABLE. THUNDERSTORM CHANCES EXPECTED TO DIMINISH FIRST
BUT THE SHOWER CHANCES MAY NOT BE FAR BEHIND. KEPT POPS IN THE
LIKELY CATEGORY OVER N GA ALL NIGHT AND THIS MAY BE OVERDONE. ALSO
AM HARD PRESSED TO INCLUDE POPS TOO FAR SE AS THE BEST MOISTURE AND
DYNAMICS DO NOT GET THAT FAR BUT ANY DEVELOPMENT WILL NEED TO BE
WATCHED THIS AFTERNOON AND OVERNIGHT.
GUIDANCE NOT BIG ON POPS SATURDAY INTO SATURDAY NIGHT WITH THE UPPER
FLOW BECOMING MORE ZONAL. WITH MOISTURE AND SOME INSTABILITY
EXPECTED...A FLAIR-UP OF SCATTERED SHOWERS AND THUNDERSTORMS SEEMS
REASONABLE FOR MUCH OF THE FORECAST AREA SATURDAY INTO SATURDAY
NIGHT.
FORECAST LOW TEMPERATURES RUNNING 5-8 DEGREES ABOVE NORMAL TONIGHT
AND SATURDAY NIGHT. FORECAST HIGH TEMPERATURES RUNNING 2-4 DEGREES
ABOVE NORMAL ON SATURDAY.
BDL
.LONG TERM /SUNDAY THROUGH FRIDAY/...
NOT MUCH CHANGE NEEDED AT THIS TIME TO THE FORECAST FOR THE
EXTENDED AS WE STILL LOOK FOR THE NEXT SIGNIFICANT SYSTEM TO
AFFECT THE AREA BY MID WEEK NEXT WEEK. THIS FAR OUT...CURRENT
GRIDS HAVE A GOOD HANDLE ON THIS AND NO CHANGES ARE PLANNED. FOR
THE INITIAL PORTION OF THE EXTENDED...PLAN TO INCREASE POPS THE
FIRST HALF OF SATURDAY NIGHT AS RESIDUAL CONVECTION LOOKS TO HANG
ON AFTER SUNSET.
DEESE
&&
.PREV DISCUSSION... /ISSUED 131 PM EDT FRI MAY 9 2014/
LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
ECMWF AND GFS CONTINUE TO SHOW HIGH PRESSURE BUILDING FROM THE
EAST ON SUNDAY AND MONDAY AS A LONG-WAVE TROUGH DEEPENS OVER THE
WESTERN THIRD OF THE COUNTRY. DESPITE THE INCREASED RIDGING...
MODELS SHOW 800-1500 J/KG OF SBCAPE DURING MAX HEATING EACH DAY...
WARRANTING A SLIGHT CHANCE OF THUNDERSTORMS EACH AFTERNOON...
ESPECIALLY ACROSS NORTH GA WHERE OROGRAPHIC LIFT MAY ENHANCE
DEVELOPMENT. OTHERWISE... THE NEXT BEST CHANCE FOR WIDESPREAD
SHOWERS AND THUNDERSTORMS CONTINUES TO BE TUESDAY THROUGH POSSIBLY
EARLY THURSDAY AS THE AFOREMENTIONED LONG-WAVE TROUGH KICKS
EASTWARD AND DRAGS A COLD FRONT ACROSS THE STATE SOMETIME MID
WEEK. THERE IS SOME TIMING DIFFERENCES BETWEEN THE MODELS... WITH
THE FASTER GFS PUSHING THE COLD FRONT INTO NW GA TUESDAY NIGHT AND
CLEARING THE FORECAST AREA BY WEDNESDAY EVENING. THE SLOWER ECMWF
SHOWS THE FRONT ENTERING NW GA WEDNESDAY AFTERNOON...THEN CLEARING
THE FORECAST AREA SOMETIME THURSDAY MORNING. PREFERRING THE MORE
CONSISTENT GFS... WILL CONTINUE TO SHOW THE GREATER POPS AND
THUNDERSTORM CHANCES ON WEDNESDAY. HOWEVER... DID ADD A SLIGHT
CHANCE OF SHOWERS EARLY ON THURSDAY AS CLEARING MAY BE SLOW.
ALTHOUGH THE GREATER UPPER SUPPORT APPEARS TO LIFT ACROSS THE OHIO
VALLEY REGION... THIS SYSTEM STILL HAS A POTENTIAL TO PRODUCE A
FEW STRONG STORMS AHEAD OF THE FRONT... AS BOTH MODELS SHOW
800-1200 J/KG OF CAPE AHEAD OF THE FRONT BY WEDNESDAY AFTERNOON...
WITH THE FASTER GFS SUGGESTING CENTRAL GA WOULD HAVE THE GREATER
STORM THREAT... WHILE THE SLOWER ECMWF WOULD BE FOCUSED MORE ON
NORTH GA ON WEDNESDAY. WITH SUCH UNCERTAINTY ON TIMING AND
STRENGTH... ALL INTEREST ARE ENCOURAGED TO CLOSELY MONITOR LATER
FORECAST CONCERNING THIS SYSTEM.
39
AVIATION...
18Z UPDATE...
MOST VFR CONDITIONS WITH SOME MVFR CEILINGS. LOW CONFIDENCE FOR
CEILINGS...VSBYS AND WEATHER THROUGH THE PERIOD. THINKING IS MOST
SHOWERS AND STORMS WILL BE N AND W OF ATL INTO TONIGHT. SURFACE WINDS
SSW AROUND 10 KTS WITH OCCASIONAL GUSTS TO 20 KTS...DIMINISHING
EARLY EVENING.
//ATL CONFIDENCE...18Z UPDATE...
LOW CONFIDENCE CEILINGS...VSBYS AND WEATHER.
MEDIUM-HIGH CONFIDENCE WINDS.
BDL
&&
.PRELIMINARY POINT TEMPS/POPS...
ATHENS 64 83 61 86 / 20 50 40 20
ATLANTA 64 82 65 84 / 40 40 30 20
BLAIRSVILLE 59 75 58 80 / 60 60 40 20
CARTERSVILLE 62 82 61 86 / 60 40 40 20
COLUMBUS 65 85 65 88 / 20 40 20 20
GAINESVILLE 63 79 62 84 / 50 50 40 20
MACON 64 85 63 88 / 10 30 20 20
ROME 63 81 61 87 / 60 40 40 20
PEACHTREE CITY 62 83 61 85 / 30 40 20 20
VIDALIA 67 86 67 89 / 10 20 20 20
&&
.FFC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...BDL
LONG TERM....DEESE
AVIATION...BDL
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
243 PM EDT FRI MAY 9 2014
.SYNOPSIS...
HIGH PRESSURE RIDGING INTO THE FORECAST AREA FROM THE ATLANTIC
WILL WEAKEN SATURDAY AS A DISSIPATING FRONTAL SYSTEM MOVES INTO
THE AREA. HIGH PRESSURE REGAINS CONTROL FOR THE BEGINNING OF NEXT
WEEK. ANOTHER FRONT IS EXPECTED TO AFFECT THE REGION LATE NEXT
WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THIS AFTERNOON...THE SURFACE RIDGE WILL CONTINUE TO EXTEND INTO THE
FORECAST AREA FROM THE ATLANTIC. THE LOWER LEVELS SHOULD REMAIN
RELATIVELY DRY. SATELLITE TRENDS SHOW CONSIDERABLE MID AND UPPER
CLOUDINESS MOVING INTO THE AREA IN THE SOUTHWEST FLOW AHEAD OF THE
TROUGH. A WEAK MID-LEVEL SHORTWAVE TROUGH...A LITTLE LOW-LEVEL
CONVERGENCE ASSOCIATED WITH A WEAK LEE-SIDE TROUGH PLUS HEATING
WILL HELP SUPPORT A FEW THUNDERSTORMS MAINLY IN THE WEST PART
CLOSER TO THE DEEPER MOISTURE. STILL...WITH JUST SHALLOW MOISTURE
AND WEAK FORCING IN THE FORECAST AREA BELIEVE COVERAGE WILL REMAIN
ISOLATED. THE LATEST HRRR INDICATES JUST ISOLATED SHOWERS OR THUNDERSTORMS.
TONIGHT...THE MODELS INDICATE AN INCREASE IN MOISTURE...BUT THE
DEEPER MOISTURE REMAINS WEST OF THE AREA. THERE MAY BE AN INCREASE
IN INSTABILITY ASSOCIATED WITH A MID-LEVEL SHORTWAVE TROUGH.
HOWEVER...MOISTURE SHOULD REMAIN LIMITED AND ANY CONVERGENCE
ASSOCIATED WITH A LEE-SIDE TROUGH SHOULD BE WEAK. THE SHOWER OR
THUNDERSTORM CHANCE IS LOW. THE NAM AND GFS MOS HAVE POPS LESS
THAN 20 PERCENT.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
THE MODELS INDICATE MOISTURE SATURDAY ASSOCIATED WITH THE
REMNANTS OF A COLD FRONT. PRECIPITABLE WATER IS FORECAST TO
INCREASE TO AROUND 1.5 INCHES WITH WEAK LIFT AHEAD OF THE BROAD
UPPER-LEVEL TROUGH. THERE SHOULD ALSO BE LITTLE LOW-LEVEL
CONVERGENCE ASSOCIATED WITH A WEAK LEE-SIDE TROUGH. KEPT CHANCE
POPS SATURDAY. THE GUIDANCE CONSENSUS SUPPORTS POPS AROUND 30
PERCENT.
THUNDERSTORMS MAY LINGER SATURDAY EVENING ASSOCIATED WITH CONVERGENCE
INTO THE WEAK LEE-SIDE TROUGH AND BAND OF MOISTURE FROM THE
REMNANTS OF THE FRONT PLUS HEATING. THE MODELS ARE CONSISTENT
SHIFTING DIMINISHING MOISTURE EAST SATURDAY NIGHT WITH H5 HEIGHTS
BUILDING. THE MODELS SHOW THE RIDGE REMAINING DOMINATE THROUGH
SUNDAY NIGHT WITH LITTLE MOISTURE. THE NAM AND GFS MOS SUPPORT
POPS LESS THAN 20 PERCENT LATE SATURDAY NIGHT THROUGH SUNDAY
NIGHT. USED THE WARMER TEMPERATURE GUIDANCE BECAUSE OF RECENT
VERIFICATION...UPPER RIDGING...AND THE DRY ENVIRONMENTAL CONDITIONS.
THE LOW TEMPERATURE GUIDANCE WAS CLOSE.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
MODELS ARE IN RELATIVELY GOOD AGREEMENT EARLY IN THE PERIOD BUT
THEN BEGIN TO DIFFER LATER IN THE WEEK. THE GFS MOVES THE UPPER
LEVEL TROF AND SFC CDFNT OUT EARLIER WHILE THE ECMWF IS SLOWER BY
24HRS. AS A RESULT CHANCES OF RAIN AND TEMPS ARE DIFFERENT. HAVE
TAKEN AN AVERAGE OF THE MOS GUIDANCE FOR EACH MODEL DAYS 5 THRU 7.
MODELS DO KEEP IT DRY EARLY IN THE WEEK THEN THE NEXT CHANCE OF
PRECIP WILL BE LATE IN THE PERIOD WHICH IS WHERE THE TIMING ISSUES
COME IN. MAX TEMPERATURES WILL BE AROUND 90 MONDAY AND TUESDAY
WITH UPPER 80S WEDNESDAY COOLING INTO THE UPPER 70S TO LOWER 80S
THURSDAY AND FRIDAY. OVERNIGHT LOWS WILL BE IN THE 60S MONDAY
THROUGH THURSDAY AND IN THE 50S FRIDAY.
&&
.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
HIGH-LEVEL CLOUDS WILL CONTINUE TO STREAM ACROSS THE TAF SITES
THROUGH THE PERIOD IN THE SOUTHWEST FLOW ALOFT. CONVERGENCE
ASSOCIATED WITH A WEAK LEE-SIDE TROUGH PLUS MID-LEVEL SHORTWAVE
TROUGH COULD HELP SUPPORT THUNDERSTORMS BUT THE CHANCE IS LOW
BECAUSE OF SHALLOW MOISTURE AND WEAK FORCING. THE HRRR INDICATES
JUST ISOLATED COVERAGE LATE THIS AFTERNOON AND THE CHANCE IS MUCH
TOO LOW TO INCLUDE IN THE TERMINAL FORECASTS AT THIS TIME. MIXING
HAS RESULTED IN WIND GUSTS AROUND 20 KNOTS THIS AFTERNOON.
DIMINISHED MIXING BEGINNING AROUND SUNSET SHOULD RESULT IN LESS
WIND. CLOUDINESS AND A LITTLE MIXING SHOULD LIMIT FOG DURING THE
EARLY MORNING HOURS SATURDAY. THE GFS AND NAM MOS INDICATE VFR
CONDITIONS.
.EXTENDED AVIATION OUTLOOK...NO SIGNIFICANT IMPACTS EXPECTED
THROUGH TUESDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
200 PM EDT FRI MAY 9 2014
.SYNOPSIS...
HIGH PRESSURE RIDGING INTO THE FORECAST AREA FROM THE ATLANTIC
WILL WEAKEN SATURDAY AS A DISSIPATING FRONTAL SYSTEM MOVES INTO
THE AREA. HIGH PRESSURE REGAINS CONTROL FOR THE BEGINNING OF NEXT
WEEK. ANOTHER FRONT IS EXPECTED TO AFFECT THE REGION LATE NEXT
WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THIS AFTERNOON...THE SURFACE RIDGE WILL CONTINUE TO EXTEND INTO THE
FORECAST AREA FROM THE ATLANTIC. THE LOWER LEVELS SHOULD REMAIN
RELATIVELY DRY. SATELLITE TRENDS SHOW CONSIDERABLE MID AND UPPER
CLOUDINESS MOVING INTO THE AREA IN THE SOUTHWEST FLOW AHEAD OF THE
TROUGH. A WEAK MID-LEVEL SHORTWAVE TROUGH...A LITTLE LOW-LEVEL
CONVERGENCE ASSOCIATED WITH A WEAK LEE-SIDE TROUGH PLUS HEATING
COULD POSSIBLY SUPPORT THUNDERSTORMS LATE...BUT THE CHANCE IS VERY
LOW BECAUSE OF SHALLOW MOISTURE AND WEAK FORCING. THE LATEST HRRR
INDICATES JUST ISOLATED SHOWERS LATE IN THE DAY. THE FORECAST
APPEARS ON TRACK WITH POPS LESS THAN 20 PERCENT. IT SHOULD BE A
LITTLE COOLER THAN PREVIOUS DAYS BECAUSE OF CLOUDINESS.
HOWEVER...IT WILL LIKELY NOT BE NOTICEABLE BECAUSE OF A SLIGHT
INCREASE IN HUMIDITY.
TONIGHT...THE MODELS INDICATE AN INCREASE IN MOISTURE...BUT THE
DEEPER MOISTURE REMAINS WEST OF THE AREA. THERE MAY BE AN INCREASE
IN INSTABILITY ASSOCIATED WITH A MID-LEVEL SHORTWAVE TROUGH.
HOWEVER...MOISTURE SHOULD REMAIN LIMITED AND ANY CONVERGENCE
ASSOCIATED WITH A LEE-SIDE TROUGH SHOULD BE WEAK. THE SHOWER OR
THUNDERSTORM CHANCE IS LOW. THE NAM AND GFS MOS HAVE POPS LESS
THAN 20 PERCENT.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
THE MODELS INDICATE MOISTURE SATURDAY ASSOCIATED WITH THE
REMNANTS OF A COLD FRONT. PRECIPITABLE WATER IS FORECAST TO
INCREASE TO AROUND 1.5 INCHES WITH WEAK LIFT AHEAD OF THE BROAD
UPPER-LEVEL TROUGH. THERE SHOULD ALSO BE LITTLE LOW-LEVEL
CONVERGENCE ASSOCIATED WITH A WEAK LEE-SIDE TROUGH. KEPT CHANCE
POPS SATURDAY. THE GUIDANCE CONSENSUS SUPPORTS POPS AROUND 30
PERCENT.
THUNDERSTORMS MAY LINGER SATURDAY EVENING ASSOCIATED WITH CONVERGENCE
INTO THE WEAK LEE-SIDE TROUGH AND BAND OF MOISTURE FROM THE
REMNANTS OF THE FRONT PLUS HEATING. THE MODELS ARE CONSISTENT
SHIFTING DIMINISHING MOISTURE EAST SATURDAY NIGHT WITH H5 HEIGHTS
BUILDING. THE MODELS SHOW THE RIDGE REMAINING DOMINATE THROUGH
SUNDAY NIGHT WITH LITTLE MOISTURE. THE NAM AND GFS MOS SUPPORT
POPS LESS THAN 20 PERCENT LATE SATURDAY NIGHT THROUGH SUNDAY
NIGHT. USED THE WARMER TEMPERATURE GUIDANCE BECAUSE OF RECENT
VERIFICATION...UPPER RIDGING...AND THE DRY ENVIRONMENTAL CONDITIONS.
THE LOW TEMPERATURE GUIDANCE WAS CLOSE.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
MODELS ARE IN RELATIVELY GOOD AGREEMENT EARLY IN THE PERIOD BUT
THEN BEGIN TO DIFFER LATER IN THE WEEK. THE GFS MOVES THE UPPER
LEVEL TROF AND SFC CDFNT OUT EARLIER WHILE THE ECMWF IS SLOWER BY
24HRS. AS A RESULT CHANCES OF RAIN AND TEMPS ARE DIFFERENT. HAVE
TAKEN AN AVERAGE OF THE MOS GUIDANCE FOR EACH MODEL DAYS 5 THRU 7.
MODELS DO KEEP IT DRY EARLY IN THE WEEK THEN THE NEXT CHANCE OF
PRECIP WILL BE LATE IN THE PERIOD WHICH IS WHERE THE TIMING ISSUES
COME IN. MAX TEMPERATURES WILL BE AROUND 90 MONDAY AND TUESDAY
WITH UPPER 80S WEDNESDAY COOLING INTO THE UPPER 70S TO LOWER 80S
THURSDAY AND FRIDAY. OVERNIGHT LOWS WILL BE IN THE 60S MONDAY
THROUGH THURSDAY AND IN THE 50S FRIDAY.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
HIGH-LEVEL CLOUDS WILL CONTINUE TO STREAM ACROSS THE TAF SITES
THROUGH THE PERIOD IN THE SOUTHWEST FLOW ALOFT. CONVERGENCE
ASSOCIATED WITH A WEAK LEE-SIDE TROUGH PLUS MID-LEVEL SHORTWAVE
TROUGH COULD HELP SUPPORT THUNDERSTORMS BUT THE CHANCE IS VERY LOW
BECAUSE OF SHALLOW MOISTURE AND WEAK FORCING. THE HRRR INDICATES
JUST ISOLATED COVERAGE LATE THIS AFTERNOON AND THE CHANCE IS MUCH
TOO LOW TO INCLUDE IN THE TERMINAL FORECASTS AT THIS TIME. THE
NAM BUFKIT MOMENTUM TRANSFER TOOL...GFS LAMP...AND KCAE 88D VAD
WIND PROFILE INDICATE WIND GUSTS 20 TO 25 KNOTS THIS AFTERNOON.
THE HIGH CLOUDINESS SHOULD LIMIT MIXING SOMEWHAT SO FORECASTED
GUSTS NEAR THE LOWER END OF THE RANGE. CLOUDINESS AND MIXING
SHOULD LIMIT FOG DURING THE EARLY MORNING HOURS SATURDAY. THE GFS
AND NAM MOS INDICATE VFR CONDITIONS.
.EXTENDED AVIATION OUTLOOK...NO SIGNIFICANT IMPACTS EXPECTED
THROUGH TUESDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
105 PM EDT FRI MAY 9 2014
.SYNOPSIS...
HIGH PRESSURE RIDGING INTO THE FORECAST AREA FROM THE ATLANTIC
WILL WEAKEN SATURDAY AS A DISSIPATING FRONTAL SYSTEM MOVES INTO
THE AREA. HIGH PRESSURE REGAINS CONTROL FOR THE BEGINNING OF NEXT
WEEK. ANOTHER FRONT IS EXPECTED TO AFFECT THE REGION LATE NEXT
WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THIS AFTERNOON...THE SURFACE RIDGE WILL CONTINUE TO EXTEND INTO THE
FORECAST AREA FROM THE ATLANTIC. THE LOWER LEVELS SHOULD REMAIN
RELATIVELY DRY. SATELLITE TRENDS SHOW CONSIDERABLE MID AND UPPER
CLOUDINESS MOVING INTO THE AREA IN THE SOUTHWEST FLOW AHEAD OF THE
TROUGH. A WEAK MID-LEVEL SHORTWAVE TROUGH...A LITTLE LOW- LEVEL
CONVERGENCE ASSOCIATED WITH A WEAK LEE-SIDE TROUGH PLUS HEATING
COULD POSSIBLY SUPPORT THUNDERSTORMS LATE...BUT THE CHANCE IS VERY
LOW BECAUSE OF SHALLOW MOISTURE AND WEAK FORCING. THE LATEST HRRR
INDICATES JUST ISOLATED SHOWERS LATE IN THE DAY. THE FORECAST
APPEARS ON TRACK WITH POPS LESS THAN 20 PERCENT. IT SHOULD BE A
LITTLE COOLER THAN PREVIOUS DAYS BECAUSE OF CLOUDINESS.
HOWEVER...IT WILL LIKELY NOT BE NOTICEABLE BECAUSE OF A SLIGHT
INCREASE IN HUMIDITY.
TONIGHT...THE MODELS INDICATE AN INCREASE IN MOISTURE...BUT THE
DEEPER MOISTURE REMAINS WEST OF THE AREA. THERE MAY BE AN INCREASE
IN INSTABILITY ASSOCIATED WITH A MID-LEVEL SHORTWAVE TROUGH.
HOWEVER...MOISTURE SHOULD REMAIN LIMITED AND ANY CONVERGENCE
ASSOCIATED WITH A LEE-SIDE TROUGH SHOULD BE WEAK. THE SHOWER OR
THUNDERSTORM CHANCE IS LOW. THE NAM AND GFS MOS HAVE POPS LESS
THAN 20 PERCENT.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
THE MODELS INDICATE AN INCREASE IN MOISTURE SATURDAY ASSOCIATED
WITH THE REMNANTS OF A COLD FRONT. PRECIPITABLE WATER IS FORECAST
TO INCREASE TO AROUND 1.5 INCHES WITH WEAK LIFT AHEAD OF THE BROAD
UPPER-LEVEL TROUGH. THERE SHOULD ALSO BE LITTLE LOW-LEVEL
CONVERGENCE ASSOCIATED WITH A WEAK LEE-SIDE TROUGH. KEPT CHANCE
POPS SATURDAY. THE GUIDANCE CONSENSUS SUPPORTS POPS AROUND 30 PERCENT.
THUNDERSTORMS MAY LINGER SATURDAY EVENING ASSOCIATED WITH CONVERGENCE
INTO THE WEAK LEE-SIDE TROUGH AND BAND OF MOISTURE FROM THE
REMNANTS OF THE FRONT PLUS HEATING. THE MODELS ARE CONSISTENT
SHIFTING DIMINISHING MOISTURE EAST SATURDAY NIGHT WITH H5 HEIGHTS
BUILDING. THE MODELS SHOW THE RIDGE REMAINING DOMINATE THROUGH
SUNDAY NIGHT WITH LITTLE MOISTURE. THE NAM AND GFS MOS SUPPORT
POPS LESS THAN 20 PERCENT LATE SATURDAY NIGHT THROUGH SUNDAY
NIGHT. USED THE WARMER TEMPERATURE GUIDANCE BECAUSE OF RECENT
VERIFICATION...UPPER RIDGING...AND THE DRY ENVIRONMENTAL CONDITIONS.
THE LOW TEMPERATURE GUIDANCE WAS CLOSE.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/... MODELS ARE IN RELATIVELY GOOD
AGREEMENT EARLY IN THE PERIOD BUT THEN BEGIN TO DIFFER LATER IN
THE WEEK. THE GFS MOVES THE UPPER LEVEL TROF AND SFC CDFNT OUT
EARLIER WHILE THE ECMWF IS SLOWER BY 24HRS. AS A RESULT CHANCES OF
RAIN AND TEMPS ARE DIFFERENT. HAVE TAKEN AN AVERAGE OF THE MOS
GUIDANCE FOR EACH MODEL DAYS 5 THRU 7. MODELS DO KEEP IT DRY EARLY
IN THE WEEK THEN THE NEXT CHANCE OF PRECIP WILL BE LATE IN THE
PERIOD WHICH IS WERE THE TIMING ISSUES COME IN. MAX TEMPERATURES
BE AROUND 90 MONDAY AND TUESDAY WITH UPPER 80S WEDNESDAY COOLING
INTO THE UPPER 70S TO LOWER 80S THURSDAY AND FRIDAY. OVERNIGHT
LOWS WILL BE IN THE 60S MONDAY THROUGH THURSDAY AND IN THE 50S
FRIDAY.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
HIGH-LEVEL CLOUDS WILL CONTINUE TO STREAM ACROSS THE TAF SITES
THROUGH THE PERIOD IN THE SOUTHWEST FLOW ALOFT. CONVERGENCE
ASSOCIATED WITH A WEAK LEE-SIDE TROUGH PLUS MID-LEVEL SHORTWAVE
TROUGH COULD HELP SUPPORT THUNDERSTORMS BUT THE CHANCE IS VERY LOW
BECAUSE OF SHALLOW MOISTURE AND WEAK FORCING. THE HRRR INDICATES
JUST ISOLATED COVERAGE LATE THIS AFTERNOON AND THE CHANCE IS MUCH
TOO LOW TO INCLUDE IN THE TERMINAL FORECASTS AT THIS TIME. THE
NAM BUFKIT MOMENTUM TRANSFER TOOL...GFS LAMP...AND KCAE 88D VAD
WIND PROFILE INDICATE WIND GUSTS 20 TO 25 KNOTS THIS AFTERNOON.
THE HIGH CLOUDINESS SHOULD LIMIT MIXING SOMEWHAT SO FORECASTED
GUSTS NEAR THE LOWER END OF THE RANGE. CLOUDINESS AND MIXING
SHOULD LIMIT FOG DURING THE EARLY MORNING HOURS SATURDAY. THE GFS
AND NAM MOS INDICATE VFR OR MVFR CONDITIONS WITH MVFR FOG CONFINED
TO THE RIVER-VALLEY TERMINALS OF AGS AND OGB.
.EXTENDED AVIATION OUTLOOK...NO SIGNIFICANT IMPACTS EXPECTED
THROUGH TUESDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1012 AM EDT FRI MAY 9 2014
.SYNOPSIS...
HIGH PRESSURE RIDGING INTO THE FORECAST AREA FROM THE ATLANTIC
WILL WEAKEN SATURDAY AS A DISSIPATING FRONTAL SYSTEM MOVES INTO
THE AREA. HIGH PRESSURE REGAINS CONTROL FOR THE BEGINNING OF NEXT
WEEK. ANOTHER FRONT IS EXPECTED TO AFFECT THE REGION LATE NEXT
WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THIS AFTERNOON...THE SURFACE RIDGE WILL CONTINUE TO EXTEND INTO THE
FORECAST AREA FROM THE ATLANTIC. THE LOWER LEVELS SHOULD REMAIN
RELATIVELY DRY. SATELLITE TRENDS SHOW CONSIDERABLE MID AND UPPER
CLOUDINESS MOVING INTO THE AREA IN THE SOUTHWEST FLOW AHEAD OF THE
TROUGH. A WEAK MID-LEVEL SHORTWAVE TROUGH...A LITTLE LOW- LEVEL
CONVERGENCE ASSOCIATED WITH A WEAK LEE-SIDE TROUGH PLUS HEATING
COULD POSSIBLY SUPPORT THUNDERSTORMS LATE...BUT THE CHANCE IS VERY
LOW BECAUSE OF SHALLOW MOISTURE AND WEAK FORCING. THE LATEST HRRR
INDICATES JUST ISOLATED SHOWERS LATE IN THE DAY. THE FORECAST
APPEARS ON TRACK WITH POPS LESS THAN 20 PERCENT. IT SHOULD BE A
LITTLE COOLER THAN PREVIOUS DAYS BECAUSE OF CLOUDINESS.
HOWEVER...IT WILL LIKELY NOT BE NOTICEABLE BECAUSE OF A SLIGHT
INCREASE IN HUMIDITY.
TONIGHT...THE MODELS INDICATE AN INCREASE IN MOISTURE...BUT THE
DEEPER MOISTURE REMAINS WEST OF THE AREA. THERE MAY BE AN INCREASE
IN INSTABILITY ASSOCIATED WITH A MID-LEVEL SHORTWAVE TROUGH.
HOWEVER...MOISTURE SHOULD REMAIN LIMITED AND ANY CONVERGENCE
ASSOCIATED WITH A LEE-SIDE TROUGH SHOULD BE WEAK. THE SHOWER OR
THUNDERSTORM CHANCE IS LOW. THE NAM AND GFS MOS HAVE POPS LESS
THAN 20 PERCENT.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
THE MODELS INDICATE AN INCREASE IN MOISTURE SATURDAY ASSOCIATED
WITH THE REMNANTS OF A COLD FRONT. PRECIPITABLE WATER IS FORECAST
TO INCREASE TO AROUND 1.5 INCHES WITH WEAK LIFT AHEAD OF THE BROAD
UPPER-LEVEL TROUGH. THERE SHOULD ALSO BE LITTLE LOW-LEVEL
CONVERGENCE ASSOCIATED WITH A WEAK LEE-SIDE TROUGH. KEPT CHANCE
POPS SATURDAY. THE GUIDANCE CONSENSUS SUPPORTS POPS AROUND 30 PERCENT.
THUNDERSTORMS MAY LINGER SATURDAY EVENING ASSOCIATED WITH CONVERGENCE
INTO THE WEAK LEE-SIDE TROUGH AND BAND OF MOISTURE FROM THE
REMNANTS OF THE FRONT PLUS HEATING. THE MODELS ARE CONSISTENT
SHIFTING DIMINISHING MOISTURE EAST SATURDAY NIGHT WITH H5 HEIGHTS
BUILDING. THE MODELS SHOW THE RIDGE REMAINING DOMINATE THROUGH
SUNDAY NIGHT WITH LITTLE MOISTURE. THE NAM AND GFS MOS SUPPORT
POPS LESS THAN 20 PERCENT LATE SATURDAY NIGHT THROUGH SUNDAY
NIGHT. USED THE WARMER TEMPERATURE GUIDANCE BECAUSE OF RECENT
VERIFICATION...UPPER RIDGING...AND THE DRY ENVIRONMENTAL CONDITIONS.
THE LOW TEMPERATURE GUIDANCE WAS CLOSE.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
THE GFS AND ECMWF DISPLAY A MAINLY DRY PATTERN MONDAY AND TUESDAY.
THE UPPER LEVEL RIDGE CONTINUES ACROSS THE REGION THROUGH TUESDAY
WHILE SURFACE HIGH PRESSURE OVER THE WESTERN ATLANTIC RIDGES INTO
THE SOUTHEASTERN STATES. THE GFS...ECMWF...AND EKD MOS INDICATE
POPS OF 20 PERCENT OR LESS. A COLD FRONT THURSDAY MAY BRING AN
INCREASED CHANCE OF THUNDERSTORMS. BOTH THE GFS AND ECMWF DISPLAY
AN OFFSHORE LOW OR TROUGH WHICH WOULD LIMIT CONVERGENCE IN THE
FORECAST AREA. THE GFS...ECMWF AND EKD MOS HAVE POPS OF 20 TO 40
PERCENT WEDNESDAY AND THURSDAY. TEMPERATURES SHOULD BE ABOVE
NORMAL IN THE UPPER 80S AND LOWER 90S SUNDAY THROUGH
WEDNESDAY...THEN NEAR NORMAL THURSDAY. SHOULD SEE OVERNIGHT LOWS
IN THE LOW TO MID 60S.
&&
.AVIATION /13Z FRIDAY THROUGH TUESDAY/...
HIGH-LEVEL CLOUDS WILL CONTINUE TO STREAM ACROSS THE TAF SITES
THROUGH THE PERIOD IN THE SOUTHWEST FLOW ALOFT. CONVERGENCE
ASSOCIATED WITH A WEAK LEE-SIDE TROUGH PLUS MID-LEVEL SHORTWAVE
TROUGH COULD HELP SUPPORT THUNDERSTORMS BUT THE CHANCE IS VERY LOW
BECAUSE OF SHALLOW MOISTURE AND WEAK FORCING. THE HRRR INDICATES
JUST ISOLATED COVERAGE LATE THIS AFTERNOON AND THE CHANCE IS MUCH
TOO LOW TO INCLUDE IN THE TERMINAL FORECASTS AT THIS TIME. THE
NAM BUFKIT MOMENTUM TRANSFER TOOL...GFS LAMP...AND KCAE 88D VAD
WIND PROFILE INDICATE WIND GUSTS 20 TO 25 KNOTS THIS AFTERNOON.
THE HIGH CLOUDINESS SHOULD LIMIT MIXING SOMEWHAT SO FORECASTED
GUSTS NEAR THE LOWER END OF THE RANGE. CLOUDINESS AND MIXING
SHOULD LIMIT FOG DURING THE EARLY MORNING HOURS SATURDAY. THE GFS
AND NAM MOS INDICATE VFR OR MVFR CONDITIONS WITH MVFR FOG CONFINED
TO THE RIVER-VALLEY TERMINALS OF AGS AND OGB.
.EXTENDED AVIATION OUTLOOK...NO SIGNIFICANT IMPACTS EXPECTED
THROUGH TUESDAY.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
202 PM CDT FRI MAY 9 2014
.DISCUSSION...
1125 AM CDT
WE CONTINUE TO MONITOR SCATTERED CONVECTION MAINLY ALONG AND EAST
OF INTERSTATE 57 GOING INTO AFTERNOON WITH A SLIGHT RISK FOR
SEVERE STORMS. NO MAJOR CHANGES MADE TO AFTERNOON TEMPERATURES OR
STORM CHANCES...WITH SOME SUBTLE ADJUSTMENTS TO HOURLY TRENDS AND
SPATIAL COVERAGE.
MAIN SWATH OF MORNING PRECIPITATION ON THE LOW-LEVEL JET HAS
SHIFTED EAST OF THE AREA. THE SURFACE COLD FRONT AND ASSOCIATED
WESTERLY WIND SHIFT AND DRY ADVECTION IS LOCATED FROM NEAR
WAUKEGAN TO JUST WEST OF PONTIAC AS OF 1115 AM. SOME SCATTERING OF
CLOUDS IN ADVANCE OF THIS ALONG WITH CONTINUED WARM/MOIST
ADVECTION AHEAD OF THE FRONT HAS LED TO DESTABILIZATION AHEAD OF
THE FRONT WITHIN A MOISTURE-RICH WARM SECTOR. SCATTERED CONVECTION
FROM THE SOUTH CHICAGO METRO TO KANKAKEE LOOKS SUPPORTED BY
INCREASING LOW-LEVEL CONVERGENCE...WHICH SHOULD CONTINUE WITH THE
BOUNDARY ADVANCING THIS AFTERNOON. AN UPSTREAM SHORT WAVE IN
EASTERN MO AND BROADER FORCING FOR ASCENT WITH UPPER JET SUPPORT
WOULD FAVOR INCREASING SHEAR AND A POTENTIAL INTENSIFICATION IN
THE SCATTERED CONVECTION AFTER 1 PM OR SO...INCLUDING THE
POSSIBILITY OF A FEW SEVERE STORMS IN THE SOUTHEAST FORECAST AREA
CONCURRENT WITH THE SPC SLIGHT RISK.
EARLIER CONVECTION THIS MORNING HAD PRODUCED SOME 40-52 MPH GUSTS
ACROSS FAR NORTHWEST INDIANA AND ANY AFTERNOON CONVECTION COULD
ALSO BE SPORADICALLY GUSTY. COOLING MID-LEVEL TEMPS AND STRONGER
UPDRAFTS MAY SUPPORT SOME MARGINALLY SEVERE HAIL WITH THE
STRONGEST STORMS AS WELL.
MTF
//PREV DISCUSSION...
335 AM CDT
MULTIPLE FORECAST CONCERNS THIS GO AROUND INCLUDING PRECIP CHANCES
TODAY...CONVECTIVE POTENTIAL LATER IN THE WEEKEND...MAGNITUDE OF
WARM UP AHEAD OF SYSTEM LATER THIS WEEKEND/EARLY NEXT WEEK...AND
THEN TRANSITION TOWARD UNSEASONABLY COOL/UNSETTLED WEATHER NEXT
WEEK.
COLD FRONT IS APPROACHING THE MISSISSIPPI RIVER EARLY THIS MORNING
WITH SOUTHERLY WINDS PUMPING WARM AND RATHER HUMID AIR NORTH INTO
THE AREA. NUMEROUS SUBTLE SHORTWAVES CONTINUE MOVE NE ACROSS THE
REGION RESULTING IN WAVES OF SHOWERS/T-STORMS. ONE WAVE IS MOVING
EAST OF THE AREA AT 08Z...HOWEVER SHORT RANGE GUIDANCE HAS BEEN
PRETTY INSISTENT THAT ANOTHER SHORTWAVE OVER MISSOURI WILL RESULT IN
AN INCREASE IN PRECIP THE NEXT SEVERAL HOURS...MOVING INTO THE
SOUTHEAST HALF TO TWO THIRDS OF THE CWA EARLY THIS MORNING.
EXTENSIVE CIRRUS MAKES SEEING THIS WAVE ON GOES IMAGERY
IMPOSSIBLE...BUT RECENT UPTICK IN SHOWERS OVER MISSOURI LENDS SOME
CREDENCE TO THE MODEL GUIDANCE AND PLAN TO CARRY HIGH POPS FOR EARLY
THIS MORNING. INSTABILITY IS FAIRLY WEAK SO NOT EXPECTING MUCH MORE
THAN JUST AN ISOLATED THUNDERSTORM OR TWO WITH MAINLY JUST SHOWERS
EARLY THIS MORNING.
COLD FRONT WILL SWEEP ACROSS THE AREA LATER THIS MORNING INTO THE
AFTERNOON USHERING IN A MUCH DRIER AIR MASS...THOUGH THE COLDER AIR
LAGS SOME BEHIND THE FRONT. THE RESULT SHOULD BE BECOMING MOSTLY
SUNNY WITH DRY WESTERLY WINDS LIKELY ALLOWING TEMPS TO HEAT UP
NICELY WELL INTO THE 70S. THERE REMAINS A CHANCE THAT THE FRONT MAY
NOT HAVE CLEARED OUR SE COUNTIES BY THE TIME CONVECTION REDEVELOPS
THIS AFTERNOON...SO HAVE MAINTAINED SOME CHANCE POPS THIS AFTERNOON
FAR SOUTHEAST CWA. ONCE FRONT MOVES EAST CONVECTIVE THREAT ENDS SE
CWA THIS AFTERNOON WITH DRY AND MILD WEATHER EXPECTED TONIGHT INTO
SATURDAY. WHILE PRESSURE GRADIENT WILL SUPPORT WEST WINDS SATURDAY
AFTERNOON...AM CONCERNED THAT GRADIENT WILL BE WEAK ENOUGH TO ALLOW
A WEAK AFTERNOON LAKE BREEZE TO DEVELOP AND CAUSING TEMPS NEAR THE
LAKE TO FALL OFF SOME IN THE AFTERNOON.
ANOTHER FAIRLY STRONG SHORTWAVE IS PROGGED TO PASS TO OUR NORTHWEST
SATURDAY NIGHT WITH STRENGTHENING WARM AIR ADVECTION REGIME SETTING
THE STAGE FOR SHOWERS/THUNDERSTORMS TO DEVELOP AGAIN SATURDAY NIGHT.
WILL LIKELY SEE SOME BREAK IN THE CONVECTION SUNDAY...WITH MUCH OF
THE DAY POTENTIALLY ENDING UP DRY AND WARM AS WE END UP BETWEEN
SYSTEMS. SYNOPTIC WARM FRONT IS PROGGED TO BE NORTH OF THE
AREA...BUT POTENTIAL EXISTS FOR NOCTURNAL CONVECTION SAT NIGHT TO
AUGMENT THE FRONTAL POSITION AND THAT RAISES SOME UNCERTAINTIES WITH
REGARDS TO TEMPS...ESPECIALLY ALONG THE LAKE BREEZE PRONE LAKE SIDE
AREAS.
NEXT STRONG SHORTWAVE IS EXPECTED TO EMERGE OUT ONTO THE CENTRAL
PLAINS LATER SUNDAY WITH CYCLOGENESIS TO OUR WEST SUNDAY NIGHT
LIKELY TO RESULT IN A SHARPENING SECONDARY WARM FRONT DEVELOPING TO
OUR SOUTH. SHOWERS/THUNDERSTORMS LOOK TO BE A GOOD BET IN THE WAA
REGIME SUNDAY NIGHT WITH SUFFICIENT SHEAR/INSTABILITY LIKELY TO BE
PRESENT TO SUPPORT SOME SEVERE POTENTIAL SUNDAY NIGHT. WARM FRONT
LIKELY TO MAKE IT NORTH OF THE CWA MONDAY...BUT TIMING DIFFERENCES
DO EXISTS BETWEEN THE GFS AND ECMWF. LEANING TOWARD THE SLOWER
TIMING OF THE ECMWF/GEM WHICH WOULD SUPPORT ANOTHER VERY WARM AND
HUMID DAY MONDAY WITH MOSTLY DRY CONDITIONS BEFORE A STRONG COLD
FRONT ARRIVES MONDAY NIGHT WITH INCREASING THREAT OF
SHOWERS/THUNDERSTORMS. SYNOPTICALLY FAVORABLE PATTERN EXISTS FOR
POTENTIALLY RESPECTABLE SEVERE WEATHER EPISODE MONDAY WITH TIMING OF
THE SYSTEM DICTATING WHETHER THE GREATEST SEVERE THREAT WILL BE HERE
OR TO OUR WEST. TOO SOON TO SAY FOR SURE...BUT MONDAY AND MONDAY
NIGHT WARRANT CLOSE ATTENTION WITH LATER FORECASTS.
BIG COLD UPPER LOW/TROUGH WILL SET UP SHOP OVER THE AREA TUESDAY
THROUGH THURSDAY. VERY COLD AIR ALOFT WITH THIS UPPER LOW //-26C AT
500MB// SHOULD SUPPORT DIURNAL SCATTERED SHOWER AND POSSIBLY ISOLD
T-STORM DEVELOPMENT. WHILE MUCH OF THE TIME WILL BE DRY TUES-THURS
THERE COULD VERY WELL BE SOME SCTD (MAINLY DIURNAL) CONVECTION
AROUND EACH DAY WHICH NECESSITATES MAINTAINING CHANCE POPS.
UNSEASONABLY COOL TEMPERATURES ARE EXPECTED WITH HIGHS STRUGGLING TO
REACH 60 BY WED AND THURSDAY.
IZZI
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* WESTERLY WINDS GUSTING TO AROUND 30 KT AT TIMES THIS AFTERNOON.
* POSSIBLE LAKE BREEZE SATURDAY AFTERNOON SHIFTING WINDS EASTERLY.
//DISCUSSION...UPDATED 18Z...
STRONG LOW PRESSURE ACROSS LAKE SUPERIOR CONTINUES TO MOVE
NORTHEAST WITH AN EXTENDING COLD FRONT HAVING PASSED THE NORTHERN
ILLINOIS AIRPORTS. THIS HAS TURNED WINDS MORE WEST-NORTHWEST.
SCATTERING OF CLOUDS BEHIND THE FRONT SHOULD MOVE ACROSS ALL TAF
SITES THIS AFTERNOON. WITH MORE EFFICIENT MIXING IN THIS
REGION...GUSTS TO AROUND 30 KT HAVE BEEN OBSERVED AND SHOULD
CONTINUE THIS AFTERNOON. SCATTERED STORMS ALONG THE FRONT WILL
REMAIN SOUTH OF THE TAF SITES...ALTHOUGH COULD GRAZE ACROSS THE
SOUTHERN TRACON AREA EARLY THIS AFTERNOON. AS THE SURFACE RIDGE
PASSES OVER THE REGION LATE TONIGHT INTO EARLY SATURDAY
MORNING...WIND SPEEDS WILL DIMINISH. THIS WILL AT LEAST ALLOW A
LAKE BREEZE TO DEVELOP. AS SOUTHWEST WINDS KICK IN BEHIND THE
FRONT IT SHOULD SLOW THE SPREAD OF THE LAKE BREEZE TO ORD AND MDW.
THERE IS STILL ANTICIPATED A SYNOPTIC SHIFT TOWARD SOUTH OR
SOUTHEAST-EAST LATE IN THE DAY/EARLY IN THE EVE EVEN IF THE LAKE
BREEZE DOES NOT ARRIVE.
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* HIGH IN WINDS THROUGH SATURDAY MORNING.
* LOW ON WHETHER WINDS TURN EASTERLY DURING SATURDAY AFTERNOON.
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...SHRA/TSRA POSSIBLE.
SUNDAY...PERIODS OF SHRA/TSRA POSSIBLE.
MONDAY...PERIODS OF SHRA/TSRA POSSIBLE.
TUESDAY THROUGH THURSDAY...CHANCE SHRA.
MTF/KJB
&&
.MARINE...
201 PM CDT
AS LOW PRESSURE AND AN ASSOCIATED COLD FRONT MOVE EAST NORTHEAST
ACROSS THE REGION...SOUTH TO SOUTHWEST WINDS PERSIST OVER THE
LAKE. A FAIRLY TIGHT PRESSURE GRADIENT IS ALLOWING FOR A 15 TO 25
KT WIND WITH OCCASIONAL GUSTS TO 30 KT ACROSS THE LAKE. ALTHOUGH
SPEEDS WILL DIMINISH ACROSS THE SOUTHERN HALF OF THE LAKE AND
ILLINOIS/INDIANA NEARSHORES THIS EVENING AND OVERNIGHT...SPEEDS
WILL STAY CLOSER TO THE 30 KT RANGE TONIGHT FOR THE NORTHERN HALF
OF THE LAKE WHERE A SURFACE TROUGH AND TIGHTER PRESSURE GRADIENT
WILL SWING THROUGH. EXPECT THE DIMINISHING TREND TO OCCUR OVER THE
NORTHERN HALF OF THE LAKE ON SATURDAY AS APPROACHING SURFACE RIDGE
OF HIGH PRESSURE PROVIDES MORE OF A RELAXED SURFACE PATTERN ACROSS
THE LAKE.
RODRIGUEZ
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 7 PM FRIDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
1259 PM CDT Fri May 9 2014
.DISCUSSION...
ISSUED 926 AM CDT Fri May 9 2014
Overnight convection has lifted northeastward out of the area,
leaving behind only a few scattered showers along/east of the I-57
corridor this morning. Cold front is currently approaching the
Illinois River. Ahead of the boundary, southwesterly winds
continue with 14z/9am temps in the upper 60s/lower 70s. Meanwhile
behind the front, W/NW winds have dropped the temp into the upper
50s around Galesburg. Front will only make slow progress eastward
today, with additional convection likely developing ahead of it
during the afternoon hours. NAM and HRRR both suggest scattered
thunderstorms will develop in the instability axis along/south of
I-70 by mid to late afternoon. In the meantime, relatively stable
airmass in the wake of the earlier convection should keep things
quiet through early afternoon. Have updated the forecast to
significantly reduce POPs this morning. Will only mention isolated
to scattered showers east of the Illinois River through midday,
then will increase POPs to likely for showers/thunder across the
SE KILX CWA this afternoon.
Barnes
&&
.AVIATION...
ISSUED 1259 PM CDT Fri May 9 2014
VFR conditions will prevail through the entire 18z TAF period. A
cold front currently just east of I-55 will push slowly eastward
this afternoon, with scattered thunderstorms developing along and
ahead of it. 1730z visible satellite imagery shows a fine line of
enhanced CU well ahead of the front that could eventually develop
into a broken line of convection over the next hour or two. This
line is already east of all terminals except KCMI, so have opted to
leave thunder mention out of the forecast at all sites at this
time. Better focus for widespread convection will remain well
south toward the I-70 corridor. Diurnal cloud cover will dissipate
by this evening, with mostly clear skies expected overnight into
Saturday morning. Winds will initially be gusty from the W/SW this
afternoon, then will diminish to less than 10kt tonight.
Barnes
&&
.PREV DISCUSSION...
ISSUED 312 AM CDT Fri May 9 2014
SHORT TERM...Today through Sunday
Surface map at 06z indicated 999 mb low pressure near KMSP with a
cold front trailing south through central IA and MO then down into
central OK where a weaker 1007 mb low resided. South flow off the
Gulf continued to pump in low to mid 60s dewpoints to central/SE
IL. Aloft, W/V imagery showed a strong warm conveyor belt overhead
which has produced rounds of thunderstorms mainly over eastern IL
for the past few hours. Another shortwave just entering SW MO was
sparking new thunderstorm development and this is expected to
shift northeast across the area through mid-morning as the cold
front moves into the western CWA. Short range models including
HRRR and SPC 4km WRF suggest this activity will push east of the
area by 18z while the cold front gradually tracks ESE across the
CWA. It appears convective debris will clear out by early
afternoon allowing upper 70s temps and mid 60s dewpoints to set up
across the eastern CWA ahead of the front. This would suggest CAPE
values around 2k J/kg with 40 kts 0-6km bulk shear overhead.
Questions remain if new convection will fire along the front as
low level convergence becomes less favorable. Any storms that
develop could become severe with damaging wind gusts and hail
given low wet-bulb zero heights near 9k ft. Radar simulations show
most favored areas would be near or south of I-70 in a 21z-02z
window.
Any lingering activity will shift east of the region overnight as
brief surface ridging moves overhead. This to provide dry and
seasonably warm weather Saturday with highs in the upper 70s/lower
80s. The pattern turns active again Saturday night as warm
advection precip ahead of the next Plains low develops in MO then
lifts northeast across the CWA. Rising heights and another round
of southerly flow ahead of this low should send another strong
warm front north of the area Saturday night or Sunday with more
associated precip chances. With the front now expected north by
Sunday afternoon and with 850 mb temps rising into the mid teens
have boosted highs to the low/mid 80s. Mixed signals if the
warm sector will be dry/capped and as a result chance pops
continue through Sunday night.
LONG TERM...Monday through Thursday
00z model suite still has some major timing differences with a strong
cold frontal passage Monday evening/night. EC continues to be most
consistent and slowest solution. Depending on timing, severe
weather will be a threat given dynamics with this system. Trends
continue to show a major pattern change behind this cold front, as
a deep upper level trough sets up over the central U.S. This will
bring well below normal temps to the region as 850 mb readings are
shown in the low single digits Tue-Thu, suggesting highs mainly
in the 60s as lows in the 40s. With cold air and deep cyclonic
flow overhead, diurnal heating may lead to scattered instability
showers Tue-Thu.
25
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS CHICAGO/ROMEOVILLE IL
1135 AM CDT FRI MAY 9 2014
.DISCUSSION...
1125 AM CDT
WE CONTINUE TO MONITOR SCATTERED CONVECTION MAINLY ALONG AND EAST
OF INTERSTATE 57 GOING INTO AFTERNOON WITH A SLIGHT RISK FOR
SEVERE STORMS. NO MAJOR CHANGES MADE TO AFTERNOON TEMPERATURES OR
STORM CHANCES...WITH SOME SUBTLE ADJUSTMENTS TO HOURLY TRENDS AND
SPATIAL COVERAGE.
MAIN SWATH OF MORNING PRECIPITATION ON THE LOW-LEVEL JET HAS
SHIFTED EAST OF THE AREA. THE SURFACE COLD FRONT AND ASSOCIATED
WESTERLY WIND SHIFT AND DRY ADVECTION IS LOCATED FROM NEAR
WAUKEGAN TO JUST WEST OF PONTIAC AS OF 1115 AM. SOME SCATTERING OF
CLOUDS IN ADVANCE OF THIS ALONG WITH CONTINUED WARM/MOIST
ADVECTION AHEAD OF THE FRONT HAS LED TO DESTABILIZATION AHEAD OF
THE FRONT WITHIN A MOISTURE-RICH WARM SECTOR. SCATTERED CONVECTION
FROM THE SOUTH CHICAGO METRO TO KANKAKEE LOOKS SUPPORTED BY
INCREASING LOW-LEVEL CONVERGENCE...WHICH SHOULD CONTINUE WITH THE
BOUNDARY ADVANCING THIS AFTERNOON. AN UPSTREAM SHORT WAVE IN
EASTERN MO AND BROADER FORCING FOR ASCENT WITH UPPER JET SUPPORT
WOULD FAVOR INCREASING SHEAR AND A POTENTIAL INTENSIFICATION IN
THE SCATTERED CONVECTION AFTER 1 PM OR SO...INCLUDING THE
POSSIBILITY OF A FEW SEVERE STORMS IN THE SOUTHEAST FORECAST AREA
CONCURRENT WITH THE SPC SLIGHT RISK.
EARLIER CONVECTION THIS MORNING HAD PRODUCED SOME 40-52 MPH GUSTS
ACROSS FAR NORTHWEST INDIANA AND ANY AFTERNOON CONVECTION COULD
ALSO BE SPORADICALLY GUSTY. COOLING MID-LEVEL TEMPS AND STRONGER
UPDRAFTS MAY SUPPORT SOME MARGINALLY SEVERE HAIL WITH THE
STRONGEST STORMS AS WELL.
MTF
&&
.PREV DISCUSSION...
335 AM CDT
MULTIPLE FORECAST CONCERNS THIS GO AROUND INCLUDING PRECIP CHANCES
TODAY...CONVECTIVE POTENTIAL LATER IN THE WEEKEND...MAGNITUDE OF
WARM UP AHEAD OF SYSTEM LATER THIS WEEKEND/EARLY NEXT WEEK...AND
THEN TRANSITION TOWARD UNSEASONABLY COOL/UNSETTLED WEATHER NEXT
WEEK.
COLD FRONT IS APPROACHING THE MISSISSIPPI RIVER EARLY THIS MORNING
WITH SOUTHERLY WINDS PUMPING WARM AND RATHER HUMID AIR NORTH INTO
THE AREA. NUMEROUS SUBTLE SHORTWAVES CONTINUE MOVE NE ACROSS THE
REGION RESULTING IN WAVES OF SHOWERS/T-STORMS. ONE WAVE IS MOVING
EAST OF THE AREA AT 08Z...HOWEVER SHORT RANGE GUIDANCE HAS BEEN
PRETTY INSISTENT THAT ANOTHER SHORTWAVE OVER MISSOURI WILL RESULT IN
AN INCREASE IN PRECIP THE NEXT SEVERAL HOURS...MOVING INTO THE
SOUTHEAST HALF TO TWO THIRDS OF THE CWA EARLY THIS MORNING.
EXTENSIVE CIRRUS MAKES SEEING THIS WAVE ON GOES IMAGERY
IMPOSSIBLE...BUT RECENT UPTICK IN SHOWERS OVER MISSOURI LENDS SOME
CREDENCE TO THE MODEL GUIDANCE AND PLAN TO CARRY HIGH POPS FOR EARLY
THIS MORNING. INSTABILITY IS FAIRLY WEAK SO NOT EXPECTING MUCH MORE
THAN JUST AN ISOLATED THUNDERSTORM OR TWO WITH MAINLY JUST SHOWERS
EARLY THIS MORNING.
COLD FRONT WILL SWEEP ACROSS THE AREA LATER THIS MORNING INTO THE
AFTERNOON USHERING IN A MUCH DRIER AIR MASS...THOUGH THE COLDER AIR
LAGS SOME BEHIND THE FRONT. THE RESULT SHOULD BE BECOMING MOSTLY
SUNNY WITH DRY WESTERLY WINDS LIKELY ALLOWING TEMPS TO HEAT UP
NICELY WELL INTO THE 70S. THERE REMAINS A CHANCE THAT THE FRONT MAY
NOT HAVE CLEARED OUR SE COUNTIES BY THE TIME CONVECTION REDEVELOPS
THIS AFTERNOON...SO HAVE MAINTAINED SOME CHANCE POPS THIS AFTERNOON
FAR SOUTHEAST CWA. ONCE FRONT MOVES EAST CONVECTIVE THREAT ENDS SE
CWA THIS AFTERNOON WITH DRY AND MILD WEATHER EXPECTED TONIGHT INTO
SATURDAY. WHILE PRESSURE GRADIENT WILL SUPPORT WEST WINDS SATURDAY
AFTERNOON...AM CONCERNED THAT GRADIENT WILL BE WEAK ENOUGH TO ALLOW
A WEAK AFTERNOON LAKE BREEZE TO DEVELOP AND CAUSING TEMPS NEAR THE
LAKE TO FALL OFF SOME IN THE AFTERNOON.
ANOTHER FAIRLY STRONG SHORTWAVE IS PROGGED TO PASS TO OUR NORTHWEST
SATURDAY NIGHT WITH STRENGTHENING WARM AIR ADVECTION REGIME SETTING
THE STAGE FOR SHOWERS/THUNDERSTORMS TO DEVELOP AGAIN SATURDAY NIGHT.
WILL LIKELY SEE SOME BREAK IN THE CONVECTION SUNDAY...WITH MUCH OF
THE DAY POTENTIALLY ENDING UP DRY AND WARM AS WE END UP BETWEEN
SYSTEMS. SYNOPTIC WARM FRONT IS PROGGED TO BE NORTH OF THE
AREA...BUT POTENTIAL EXISTS FOR NOCTURNAL CONVECTION SAT NIGHT TO
AUGMENT THE FRONTAL POSITION AND THAT RAISES SOME UNCERTAINTIES WITH
REGARDS TO TEMPS...ESPECIALLY ALONG THE LAKE BREEZE PRONE LAKE SIDE
AREAS.
NEXT STRONG SHORTWAVE IS EXPECTED TO EMERGE OUT ONTO THE CENTRAL
PLAINS LATER SUNDAY WITH CYCLOGENESIS TO OUR WEST SUNDAY NIGHT
LIKELY TO RESULT IN A SHARPENING SECONDARY WARM FRONT DEVELOPING TO
OUR SOUTH. SHOWERS/THUNDERSTORMS LOOK TO BE A GOOD BET IN THE WAA
REGIME SUNDAY NIGHT WITH SUFFICIENT SHEAR/INSTABILITY LIKELY TO BE
PRESENT TO SUPPORT SOME SEVERE POTENTIAL SUNDAY NIGHT. WARM FRONT
LIKELY TO MAKE IT NORTH OF THE CWA MONDAY...BUT TIMING DIFFERENCES
DO EXISTS BETWEEN THE GFS AND ECMWF. LEANING TOWARD THE SLOWER
TIMING OF THE ECMWF/GEM WHICH WOULD SUPPORT ANOTHER VERY WARM AND
HUMID DAY MONDAY WITH MOSTLY DRY CONDITIONS BEFORE A STRONG COLD
FRONT ARRIVES MONDAY NIGHT WITH INCREASING THREAT OF
SHOWERS/THUNDERSTORMS. SYNOPTICALLY FAVORABLE PATTERN EXISTS FOR
POTENTIALLY RESPECTABLE SEVERE WEATHER EPISODE MONDAY WITH TIMING OF
THE SYSTEM DICTATING WHETHER THE GREATEST SEVERE THREAT WILL BE HERE
OR TO OUR WEST. TOO SOON TO SAY FOR SURE...BUT MONDAY AND MONDAY
NIGHT WARRANT CLOSE ATTENTION WITH LATER FORECASTS.
BIG COLD UPPER LOW/TROUGH WILL SET UP SHOP OVER THE AREA TUESDAY
THROUGH THURSDAY. VERY COLD AIR ALOFT WITH THIS UPPER LOW //-26C AT
500MB// SHOULD SUPPORT DIURNAL SCATTERED SHOWER AND POSSIBLY ISOLD
T-STORM DEVELOPMENT. WHILE MUCH OF THE TIME WILL BE DRY TUES-THURS
THERE COULD VERY WELL BE SOME SCTD (MAINLY DIURNAL) CONVECTION
AROUND EACH DAY WHICH NECESSITATES MAINTAINING CHANCE POPS.
UNSEASONABLY COOL TEMPERATURES ARE EXPECTED WITH HIGHS STRUGGLING TO
REACH 60 BY WED AND THURSDAY.
IZZI
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* NEARBY SHRA TO MDW THROUGH 1730Z OR SO...WITH SCATTERED CONVECTION
IN THE SOUTHERN TRACON AREA.
* MVFR CIGS DISSIPATING BY EARLY THIS AFTERNOON.
* GUSTY SOUTHWESTERLY WINDS THIS AFTERNOON.
MTF/KJB
//DISCUSSION...UPDATED 16Z...
COLD FRONT IS MOVING EAST ACROSS NORTHERN IL ALTHOUGH SLOWING LATE
THIS MORNING. SCATTERED SHRA/TSRA ARE DEVELOPING AHEAD OF THIS
FROM JUST SOUTH OF MDW TO NEAR PNT. THESE ARE FAVORED TO
REGENERATE THROUGH MID AFTERNOON BEFORE PUSHING EAST. THESE ARE
HIGHLY LIKELY TO REMAIN SOUTH OF ORD BUT MDW IT MAY BE CLOSE FOR A
FEW HOURS.
//PREV DISCUSSION...UPDATED 12Z...
THE THREAT FOR THUNDERSTORMS IS QUICKLY ENDING ACROSS THE AREA.
HOWEVER...PERIODS OF SHOWERS WILL CONTINUE FOR A COUPLE MORE HOURS
THIS MORNING...BEFORE ENDING. THE INCREASE IN LOWER LEVEL MOISTURE
HAS ALSO LEAD TO SOME LOWER MVFR TO EVEN SOME IFR CIGS ACROSS
PORTIONS OF THE AREA THIS MORNING. THESE LOWER CIGS ARE EXPECTED
TO BE FAIRLY SHORT LIVED...WITH IMPROVEMENT TO VFR CONDITIONS
EXPECTED BY MID TO LATE MORNING.
THE WINDS WILL REMAIN GUSTY OUT OF THE SOUTH-SOUTHWEST...WITH GUSTS
LIKELY UP AROUND 25 KT THROUGH MUCH OF THE DAY. A COOL FRONT WILL
SHIFT ACROSS THE AREA BY LATE AFTERNOON/EARLY EVENING...WITH WINDS
EXPECTED TO BECOME MORE WESTERLY AND ABATE BY EVENING.
KJB
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* HIGH THAT SHRA/TSRA WILL BE SOUTH OF MDW BY 19Z.
* HIGH WITH WIND TRENDS.
* MEDIUM WITH TIMING OF CIGS LIFTING TO VFR.
MTF/KJB
//OUTLOOK FOR ORD/MDW FOR 00Z SUNDAY-12Z FRIDAY...UPDATED 12Z...
SATURDAY NIGHT...SHRA/TSRA POSSIBLE.
SUNDAY...PERIODS OF SHRA/TSRA POSSIBLE.
MONDAY...PERIODS OF SHRA/TSRA POSSIBLE.
TUESDAY THROUGH THURSDAY...CHANCE SHRA.
KJB
&&
.MARINE...
223 AM CDT
LOW PRESSURE WILL SHIFT NORTHEASTWARD ACROSS THE LAKE SUPERIOR
TODAY. THIS WILL RESULT IN ANOTHER DAY OF GUSTY SOUTH-SOUTHWESTERLY
WINDS UP AROUND 25 KT ACROSS THE LAKE. A RIDGE OF HIGH PRESSURE WILL
BUILD EASTWARD FROM THE MIDWEST TO LAKE MICHIGAN BY SATURDAY...WITH
LIGHTER WINDS EXPECTED TO ACCOMPANY THIS RIDGE OF HIGH PRESSURE.
ANOTHER AREA OF LOW PRESSURE IS FORECAST TO LIFT NORTHEASTWARD
ACROSS THE UPPER MIDWEST EARLY NEXT WEEK...AND THIS LOOKS TO RESULT IN
ANOTHER ACTIVE PERIOD OF WEATHER OVER THE A LAKE INTO THE MIDDLE OF
NEXT WEEK. THIS COULD INCLUDE A PERIOD OF STRONGER SOUTHERLY WINDS
AND MORE SHOWERS AND THUNDERSTORMS.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 7 PM FRIDAY.
&&
$$
VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE)
FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT:
WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV
WWW.TWITTER.COM/NWSCHICAGO
WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion
National Weather Service Lincoln IL
926 AM CDT Fri May 9 2014
.DISCUSSION...
ISSUED 926 AM CDT Fri May 9 2014
Overnight convection has lifted northeastward out of the area,
leaving behind only a few scattered showers along/east of the I-57
corridor this morning. Cold front is currently approaching the
Illinois River. Ahead of the boundary, southwesterly winds
continue with 14z/9am temps in the upper 60s/lower 70s. Meanwhile
behind the front, W/NW winds have dropped the temp into the upper
50s around Galesburg. Front will only make slow progress eastward
today, with additional convection likely developing ahead of it
during the afternoon hours. NAM and HRRR both suggest scattered
thunderstorms will develop in the instability axis along/south of
I-70 by mid to late afternoon. In the meantime, relatively stable
airmass in the wake of the earlier convection should keep things
quiet through early afternoon. Have updated the forecast to
significantly reduce POPs this morning. Will only mention isolated
to scattered showers east of the Illinois River through midday,
then will increase POPs to likely for showers/thunder across the
SE KILX CWA this afternoon.
Barnes
&&
.AVIATION...
ISSUED 656 AM CDT Fri May 9 2014
The slow moving cold front will finally push across the terminal
sites today. MVFR clouds between 1500-2500 FT will become more
widespread during the first 3 to 5 hours of the TAFs, as low
clouds develop near the front. A break in the rain should
eventually work its way from west to east behind the front. The
front should pass PIA to SPI by 16z, then reach CMI to DEC by 21z.
The MVFR cigs should gradually give way to VFR cigs behind the
front this afternoon. Storm redevelopment is expected later this
afternoon ahead of the front, but the majority of those storms
should be southeast of the TAF sites. DEC and CMI could get
clipped as the line of storms develops after 20z, so a VCTS was
left in the TAFS from 20z to 01z.
Surface winds will remain out of a southerly direction at 12 to
17 kts early this morning with gusts to 25kt or higher at times
in and near any thunderstorms. Winds will veer more into the
southwest and then west this afternoon with speeds in the 15 to 20 kt
range with gusts up to 30 kts possible, especially if we can get
some sunshine to break through. VFR conditions are expected across
the entire forecast area this evening thru 12z.
Shimon
&&
.PREV DISCUSSION...
ISSUED 312 AM CDT Fri May 9 2014
SHORT TERM...Today through Sunday
Surface map at 06z indicated 999 mb low pressure near KMSP with a
cold front trailing south through central IA and MO then down into
central OK where a weaker 1007 mb low resided. South flow off the
Gulf continued to pump in low to mid 60s dewpoints to central/SE
IL. Aloft, W/V imagery showed a strong warm conveyor belt overhead
which has produced rounds of thunderstorms mainly over eastern IL
for the past few hours. Another shortwave just entering SW MO was
sparking new thunderstorm development and this is expected to
shift northeast across the area through mid-morning as the cold
front moves into the western CWA. Short range models including
HRRR and SPC 4km WRF suggest this activity will push east of the
area by 18z while the cold front gradually tracks ESE across the
CWA. It appears convective debris will clear out by early
afternoon allowing upper 70s temps and mid 60s dewpoints to set up
across the eastern CWA ahead of the front. This would suggest CAPE
values around 2k J/kg with 40 kts 0-6km bulk shear overhead.
Questions remain if new convection will fire along the front as
low level convergence becomes less favorable. Any storms that
develop could become severe with damaging wind gusts and hail
given low wet-bulb zero heights near 9k ft. Radar simulations show
most favored areas would be near or south of I-70 in a 21z-02z
window.
Any lingering activity will shift east of the region overnight as
brief surface ridging moves overhead. This to provide dry and
seasonably warm weather Saturday with highs in the upper 70s/lower
80s. The pattern turns active again Saturday night as warm
advection precip ahead of the next Plains low develops in MO then
lifts northeast across the CWA. Rising heights and another round
of southerly flow ahead of this low should send another strong
warm front north of the area Saturday night or Sunday with more
associated precip chances. With the front now expected north by
Sunday afternoon and with 850 mb temps rising into the mid teens
have boosted highs to the low/mid 80s. Mixed signals if the
warm sector will be dry/capped and as a result chance pops
continue through Sunday night.
LONG TERM...Monday through Thursday
00z model suite still has some major timing differences with a strong
cold frontal passage Monday evening/night. EC continues to be most
consistent and slowest solution. Depending on timing, severe
weather will be a threat given dynamics with this system. Trends
continue to show a major pattern change behind this cold front, as
a deep upper level trough sets up over the central U.S. This will
bring well below normal temps to the region as 850 mb readings are
shown in the low single digits Tue-Thu, suggesting highs mainly
in the 60s as lows in the 40s. With cold air and deep cyclonic
flow overhead, diurnal heating may lead to scattered instability
showers Tue-Thu.
25
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1035 PM EDT SAT MAY 10 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 245 PM EDT SAT MAY 10 2014
A FRONT WILL MEANDER ACROSS THE AREA THIS WEEKEND KEEPING CHANCES
FOR RAIN IN THE FORECAST. ANOTHER FRONT WILL BRING MORE RAIN CHANCES
NEXT WEEK. TEMPERATURES WILL WARM TO ABOVE AVERAGE BY EARLY NEXT
WEEK...THEN FALL TO BELOW AVERAGE FROM MID WEEK ON BEHIND THE COLD
FRONT.
&&
.NEAR TERM /OVERNIGHT/...
ISSUED AT 1004 PM EDT SAT MAY 10 2014
CLOUD DEBRIS FROM WARM FRONTAL CONVECTION ACROSS MISSOURI ALREADY
RETURNING INTO THE HOOSIER STATE AS OF 0130Z. TEMPS WERE PRIMARILY
IN THE 60S AT THE MID EVENING POINT.
FRONTAL BOUNDARY AT 0130Z EXTENDING ACROSS FAR SOUTHERN INDIANA
BACK TO NEAR KSTL THEN CONTINUING WEST INTO NORTH CENTRAL
MISSOURI. BOUNDARY ALREADY SHOWING SIGNS OF LIFTING BACK NORTH
OVER THE LAST FEW HOURS...AND WILL CONTINUE TO DO SO OVERNIGHT.
IMPRESSIVE POCKET OF DRY AIR HAS SLIPPED SOUTH INTO NORTHERN PORTIONS
OF THE FORECAST AREA...WITH DEWPOINTS INTO THE MIDDLE/UPPER 30S
FROM INDY NORTHEAST. THESE LOWER DEWPOINTS WILL QUICKLY RECOVER AS
THE BOUNDARY RETURNS INTO THE FORECAST AREA OVER THE NEXT SEVERAL
HOURS.
THE MAIN ISSUE FOR THE UPDATE IS THE EXPECTED TRACK OF THE
CONVECTION ACROSS THE MID MISSISSIPPI VALLEY AND THE STATE OF
INTENSITY ITS LIKELY TO BE IN WHEN IT ARRIVES IN THE REGION. BOTH
THE RAP AND HRRR MOVE CONVECTION ALONG THE WARM FRONT OVER THE
NEXT FEW HOURS...LIKELY REACHING THE WABASH RIVER BETWEEN KHUF AND
KLWV BY AROUND 07Z. EXPECT SHOWERS AND EMBEDDED STORMS TO
OVERSPREAD PRIMARILY THE SOUTHERN HALF OF THE FORECAST AREA IN A
WEAKENED CONDITION THEREAFTER AS THE WARM FRONT LIFTS NORTH. WILL
CARRY LOWER POPS FURTHER NORTH.
OVERNIGHT LOWS RANGING FROM THE MID 50S OVER NORTHEAST COUNTIES TO
THE MID 60S IN THE LOWER WABASH VALLEY LOOK REASONABLE AND LITTLE
CHANGE WAS MADE. ZONE AND GRID UPDATES OUT.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
ISSUED AT 245 PM EDT SAT MAY 10 2014
FOCUS WILL CONTINUE TO BE ON THUNDERSTORM CHANCES THROUGH THE ENTIRE
SHORT TERM AS LOW PRESSURE SYSTEM GRADUALLY MIGRATES EAST FROM THE
PLAINS.
ECMWF CONTINUES TO BE THE MOST CONSISTENT OF THE MODELS REGARD
SLOWLY MOVING FRONTAL SYSTEM. ASSOCIATED COLD FRONT LOOKS LIKE IT
WILL NOT MOVE ACROSS CENTRAL INDIANA UNTIL TUESDAY AFTERNOON AND
NIGHT.
ON SUNDAY...WARM FRONT SHOULD LIFT NORTHEAST ACROSS CENTRAL INDIANA
WHICH SHOULD TRIGGER SCATTERED THUNDERSTORMS WITH MODELS ALL SHOWING
MIXED LAYER CAPES FROM 1000-2000 J/KG...INCREASED LOW LEVEL MOISTURE
AND SOME RESULTING QPF. THEN...WITH THE AREA IN THE WARM SECTOR FROM
SUNDAY NIGHT THROUGH MONDAY NIGHT...SHOULD SEE WARMER TEMPERATURES
IN THE 80S ON MONDAY PER 12Z MOS BLEND AND CONSALL. WILL STICK WITH
LOW POPS SUNDAY NIGHT THROUGH MONDAY NIGHT WITH AMPLE INSTABILITY
AND POSSIBLY LEFTOVER OUTFLOW BOUNDARIES BUT ONLY WEAK SYNOPTIC
FORCING WITH UPPER WAVES IN SOUTHWEST FLOW.
BEST CHANCE OF THUNDERSTORMS WILL BE ON TUESDAY AS THE FRONT
APPROACHES AND MOVES AT LEAST PART OF THE WAY ACROSS THE FORECAST
AREA.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
ISSUED AT 245 PM EDT SAT MAY 10 2014
ENSEMBLES INDICATE A SLOWLY PROGRESSIVE NATURE TO THE MAIN UPPER
FEATURES DURING THIS PERIOD. A DEEP TROUGH THAT IS EXPECTED TO BE
OVER THE MIDWEST BY THE MIDDLE OF NEXT WEEK WILL GRADUALLY SETTLE
INTO THE GREAT LAKES/OHIO VALLEY BY NEXT WEEKEND.
SOME OF THE ENSEMBLES SUGGEST A SECONDARY WAVE OF LOW PRESSURE MAY
DEVELOP ALONG THE MAIN FRONT TOWARDS THE MIDDLE OF NEXT WEEK WHILE
OTHERS ARE QUICKER WITH THE PASSAGE OF THE FRONT. IN EITHER
CASE...IT APPEARS THE HIGHEST PRECIPITATION THREAT WILL BE TUESDAY
NIGHT INTO WEDNESDAY WITH THE PASSAGE OF THE SURFACE FRONT AND
POTENTIAL SECONDARY WAVE.
AFTER THAT...COOL AND SHOWERY CONDITIONS EXPECTED INTO NEXT WEEKEND
ASSOCIATED WITH THE INSTABILITY NEAR THE DEEP UPPER TROUGH AND ANY
POTENTIAL DISTURBANCES THAT MAY RIPPLE THROUGH IT. WILL KEEP POPS
GOING THROUGHOUT THE EXTENDED PERIOD.
&&
.AVIATION /DISCUSSION FOR 110300Z TAF ISSUANCE/...
ISSUED AT 1035 PM EDT SAT MAY 10 2014
SITES WILL START OUT VFR AND DRY WITH A FRONT ACROSS SOUTHERN
INDIANA. THIS WILL SLOWLY LIFT NORTH AS A WARM FRONT. EXPECT WINDS
TO BE LIGHT AND VARIABLE DURING THE OVERNIGHT BUT PICK UP AGAIN
SUNDAY MORNING OUT OF THE SOUTHEAST AND THEN SOUTH BY SUNDAY
AFTERNOON...AROUND 5-8 KTS IN THE MORNING THEN 8-12 IN THE AFTERNOON.
A COUPLE MODELS ARE SHOWING SOME POTENTIAL FOR CONVECTIVE
DEVELOPMENT DURING THE OVERNIGHT AS WELL...WITH THE BEST CHANCES
AFTER 8Z OR SO. WITH CONVECTION EVIDENT IN WESTERN ILLINOIS HAVE
ADDED VCTS AND SHRA TO ALL SITES BUT KLAF AS NORTHWARD EXTENT IS
STILL IN QUESTION. MORE CHANCES FOR RAIN AND THUNDER ARE IN THE
FORECAST FOR SUNDAY...BUT UNCERTAINTY IS HIGH ENOUGH TO LEAVE OUT
FOR NOW AND JUST INCLUDE A BROKEN DECK DURING THE AFTERNOON.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...MK
NEAR TERM...RYAN
SHORT TERM...MK
LONG TERM....JAS
AVIATION...CP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1004 PM EDT SAT MAY 10 2014
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 245 PM EDT SAT MAY 10 2014
A FRONT WILL MEANDER ACROSS THE AREA THIS WEEKEND KEEPING CHANCES
FOR RAIN IN THE FORECAST. ANOTHER FRONT WILL BRING MORE RAIN CHANCES
NEXT WEEK. TEMPERATURES WILL WARM TO ABOVE AVERAGE BY EARLY NEXT
WEEK...THEN FALL TO BELOW AVERAGE FROM MID WEEK ON BEHIND THE COLD
FRONT.
&&
.NEAR TERM /OVERNIGHT/...
ISSUED AT 1004 PM EDT SAT MAY 10 2014
CLOUD DEBRIS FROM WARM FRONTAL CONVECTION ACROSS MISSOURI ALREADY
RETURNING INTO THE HOOSIER STATE AS OF 0130Z. TEMPS WERE PRIMARILY
IN THE 60S AT THE MID EVENING POINT.
FRONTAL BOUNDARY AT 0130Z EXTENDING ACROSS FAR SOUTHERN INDIANA
BACK TO NEAR KSTL THEN CONTINUING WEST INTO NORTH CENTRAL
MISSOURI. BOUNDARY ALREADY SHOWING SIGNS OF LIFTING BACK NORTH
OVER THE LAST FEW HOURS...AND WILL CONTINUE TO DO SO OVERNIGHT.
IMPRESSIVE POCKET OF DRY AIR HAS SLIPPED SOUTH INTO NORTHERN PORTIONS
OF THE FORECAST AREA...WITH DEWPOINTS INTO THE MIDDLE/UPPER 30S
FROM INDY NORTHEAST. THESE LOWER DEWPOINTS WILL QUICKLY RECOVER AS
THE BOUNDARY RETURNS INTO THE FORECAST AREA OVER THE NEXT SEVERAL
HOURS.
THE MAIN ISSUE FOR THE UPDATE IS THE EXPECTED TRACK OF THE
CONVECTION ACROSS THE MID MISSISSIPPI VALLEY AND THE STATE OF
INTENSITY ITS LIKELY TO BE IN WHEN IT ARRIVES IN THE REGION. BOTH
THE RAP AND HRRR MOVE CONVECTION ALONG THE WARM FRONT OVER THE
NEXT FEW HOURS...LIKELY REACHING THE WABASH RIVER BETWEEN KHUF AND
KLWV BY AROUND 07Z. EXPECT SHOWERS AND EMBEDDED STORMS TO
OVERSPREAD PRIMARILY THE SOUTHERN HALF OF THE FORECAST AREA IN A
WEAKENED CONDITION THEREAFTER AS THE WARM FRONT LIFTS NORTH. WILL
CARRY LOWER POPS FURTHER NORTH.
OVERNIGHT LOWS RANGING FROM THE MID 50S OVER NORTHEAST COUNTIES TO
THE MID 60S IN THE LOWER WABASH VALLEY LOOK REASONABLE AND LITTLE
CHANGE WAS MADE. ZONE AND GRID UPDATES OUT.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
ISSUED AT 245 PM EDT SAT MAY 10 2014
FOCUS WILL CONTINUE TO BE ON THUNDERSTORM CHANCES THROUGH THE ENTIRE
SHORT TERM AS LOW PRESSURE SYSTEM GRADUALLY MIGRATES EAST FROM THE
PLAINS.
ECMWF CONTINUES TO BE THE MOST CONSISTENT OF THE MODELS REGARD
SLOWLY MOVING FRONTAL SYSTEM. ASSOCIATED COLD FRONT LOOKS LIKE IT
WILL NOT MOVE ACROSS CENTRAL INDIANA UNTIL TUESDAY AFTERNOON AND
NIGHT.
ON SUNDAY...WARM FRONT SHOULD LIFT NORTHEAST ACROSS CENTRAL INDIANA
WHICH SHOULD TRIGGER SCATTERED THUNDERSTORMS WITH MODELS ALL SHOWING
MIXED LAYER CAPES FROM 1000-2000 J/KG...INCREASED LOW LEVEL MOISTURE
AND SOME RESULTING QPF. THEN...WITH THE AREA IN THE WARM SECTOR FROM
SUNDAY NIGHT THROUGH MONDAY NIGHT...SHOULD SEE WARMER TEMPERATURES
IN THE 80S ON MONDAY PER 12Z MOS BLEND AND CONSALL. WILL STICK WITH
LOW POPS SUNDAY NIGHT THROUGH MONDAY NIGHT WITH AMPLE INSTABILITY
AND POSSIBLY LEFTOVER OUTFLOW BOUNDARIES BUT ONLY WEAK SYNOPTIC
FORCING WITH UPPER WAVES IN SOUTHWEST FLOW.
BEST CHANCE OF THUNDERSTORMS WILL BE ON TUESDAY AS THE FRONT
APPROACHES AND MOVES AT LEAST PART OF THE WAY ACROSS THE FORECAST
AREA.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
ISSUED AT 245 PM EDT SAT MAY 10 2014
ENSEMBLES INDICATE A SLOWLY PROGRESSIVE NATURE TO THE MAIN UPPER
FEATURES DURING THIS PERIOD. A DEEP TROUGH THAT IS EXPECTED TO BE
OVER THE MIDWEST BY THE MIDDLE OF NEXT WEEK WILL GRADUALLY SETTLE
INTO THE GREAT LAKES/OHIO VALLEY BY NEXT WEEKEND.
SOME OF THE ENSEMBLES SUGGEST A SECONDARY WAVE OF LOW PRESSURE MAY
DEVELOP ALONG THE MAIN FRONT TOWARDS THE MIDDLE OF NEXT WEEK WHILE
OTHERS ARE QUICKER WITH THE PASSAGE OF THE FRONT. IN EITHER
CASE...IT APPEARS THE HIGHEST PRECIPITATION THREAT WILL BE TUESDAY
NIGHT INTO WEDNESDAY WITH THE PASSAGE OF THE SURFACE FRONT AND
POTENTIAL SECONDARY WAVE.
AFTER THAT...COOL AND SHOWERY CONDITIONS EXPECTED INTO NEXT WEEKEND
ASSOCIATED WITH THE INSTABILITY NEAR THE DEEP UPPER TROUGH AND ANY
POTENTIAL DISTURBANCES THAT MAY RIPPLE THROUGH IT. WILL KEEP POPS
GOING THROUGHOUT THE EXTENDED PERIOD.
&&
.AVIATION /DISCUSSION FOR 110000Z TAF ISSUANCE/...
ISSUED AT 647 PM EDT SAT MAY 10 2014
SITES WILL START OUT VFR AND DRY WITH NORTHWESTERLY WINDS WITH A
FRONT STALLED NEAR THE OHIO RIVER. THIS WILL SLOWLY LIFT NORTH AS
A WARM FRONT. EXPECT WINDS TO BE LIGHT AND VARIABLE DURING THE
OVERNIGHT BUT PICK UP AGAIN SUNDAY MORNING OUT OF THE SOUTHEAST
AND THEN SOUTH BY SUNDAY AFTERNOON...AROUND 5-8 KTS IN THE MORNING
THEN 8-12 IN THE AFTERNOON.
A COUPLE MODELS ARE SHOWING SOME POTENTIAL FOR CONVECTIVE
DEVELOPMENT DURING THE OVERNIGHT AS WELL...WITH THE BEST CHANCES
AFTER 6Z OR SO. SOME UNCERTAINTY ON HOW THIS WILL PLAY OUT...SO
WILL INCLUDE A BROKEN DECK AT 040 BUT NO PRECIP AT THIS TIME. ALSO
WITH THE FRONT LIFTING NORTH COULD SEE MOISTURE INCREASE AT KBMG
AND THUS SOME POTENTIAL FOR MVFR FOG THERE AND INCLUDED A TEMPO
GROUP AFTER 11Z. MORE CHANCES FOR RAIN AND THUNDER ARE IN THE
FORECAST FOR SUNDAY...BUT UNCERTAINTY IS HIGH ENOUGH TO LEAVE OUT
FOR NOW AND JUST INCLUDE A BROKEN DECK DURING THE AFTERNOON.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...MK
NEAR TERM...RYAN
SHORT TERM...MK
LONG TERM....JAS
AVIATION...CP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1000 PM EDT SAT MAY 10 2014
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 245 PM EDT SAT MAY 10 2014
A FRONT WILL MEANDER ACROSS THE AREA THIS WEEKEND KEEPING CHANCES
FOR RAIN IN THE FORECAST. ANOTHER FRONT WILL BRING MORE RAIN CHANCES
NEXT WEEK. TEMPERATURES WILL WARM TO ABOVE AVERAGE BY EARLY NEXT
WEEK...THEN FALL TO BELOW AVERAGE FROM MID WEEK ON BEHIND THE COLD
FRONT.
&&
.NEAR TERM /OVERNIGHT/...
ISSUED AT 1000 PM EDT SAT MAY 10 2014
CLOUD DEBRIS FROM WARM FRONTAL CONVECTION ACROSS MISSOURI ALREADY
RETURNING INTO THE HOOSIER STATE AS OF 0130Z. TEMPS WERE PRIMARILY
IN THE 60S AT THE MID EVENING POINT.
FRONTAL BOUNDARY AT 0130Z EXTENDING ACROSS FAR SOUTHERN INDIANA
BACK TO NEAR KSTL THEN CONTINUING WEST INTO NORTH CENTRAL
MISSOURI. BOUNDARY ALREADY SHOWING SIGNS OF LIFTING BACK NORTH
OVER THE LAST FEW HOURS...AND WILL CONTINUE TO DO SO OVERNIGHT.
IMPRESSIVE POCKET OF DRY AIR HAS SLIPPED SOUTH INTO NORTHERN PORTIONS
OF THE FORECAST AREA...WITH DEWPOINTS INTO THE MIDDLE/UPPER 30S
FROM INDY NORTHEAST. THESE LOWER DEWPOINTS WILL QUICKLY RECOVER AS
THE BOUNDARY RETURNS INTO THE FORECAST AREA OVER THE NEXT SEVERAL
HOURS.
THE MAIN ISSUE FOR THE UPDATE IS THE EXPECTED TRACK OF THE
CONVECTION ACROSS THE MID MISSISSIPPI VALLEY AND THE STATE OF
INTENSITY ITS LIKELY TO BE IN WHEN IT ARRIVES IN THE REGION. BOTH
THE RAP AND HRRR MOVE CONVECTION ALONG THE WARM FRONT OVER THE
NEXT FEW HOURS...LIKELY REACHING THE WABASH RIVER BETWEEN KHUF AND
KLWV BY AROUND 05Z. EXPECT SHOWERS AND EMBEDDED STORMS TO
OVERSPREAD PRIMARILY THE SOUTHERN HALF OF THE FORECAST AREA IN A
WEAKENED CONDITION AFTER 06Z AS THE WARM FRONT LIFTS NORTH. WILL
CARRY LOWER POPS FURTHER NORTH.
OVERNIGHT LOWS RANGING FROM THE MID 50S OVER NORTHEAST COUNTIES TO
THE MID 60S IN THE LOWER WABASH VALLEY LOOK REASONABLE AND LITTLE
CHANGE WAS MADE. ZONE AND GRID UPDATES OUT.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
ISSUED AT 245 PM EDT SAT MAY 10 2014
FOCUS WILL CONTINUE TO BE ON THUNDERSTORM CHANCES THROUGH THE ENTIRE
SHORT TERM AS LOW PRESSURE SYSTEM GRADUALLY MIGRATES EAST FROM THE
PLAINS.
ECMWF CONTINUES TO BE THE MOST CONSISTENT OF THE MODELS REGARD
SLOWLY MOVING FRONTAL SYSTEM. ASSOCIATED COLD FRONT LOOKS LIKE IT
WILL NOT MOVE ACROSS CENTRAL INDIANA UNTIL TUESDAY AFTERNOON AND
NIGHT.
ON SUNDAY...WARM FRONT SHOULD LIFT NORTHEAST ACROSS CENTRAL INDIANA
WHICH SHOULD TRIGGER SCATTERED THUNDERSTORMS WITH MODELS ALL SHOWING
MIXED LAYER CAPES FROM 1000-2000 J/KG...INCREASED LOW LEVEL MOISTURE
AND SOME RESULTING QPF. THEN...WITH THE AREA IN THE WARM SECTOR FROM
SUNDAY NIGHT THROUGH MONDAY NIGHT...SHOULD SEE WARMER TEMPERATURES
IN THE 80S ON MONDAY PER 12Z MOS BLEND AND CONSALL. WILL STICK WITH
LOW POPS SUNDAY NIGHT THROUGH MONDAY NIGHT WITH AMPLE INSTABILITY
AND POSSIBLY LEFTOVER OUTFLOW BOUNDARIES BUT ONLY WEAK SYNOPTIC
FORCING WITH UPPER WAVES IN SOUTHWEST FLOW.
BEST CHANCE OF THUNDERSTORMS WILL BE ON TUESDAY AS THE FRONT
APPROACHES AND MOVES AT LEAST PART OF THE WAY ACROSS THE FORECAST
AREA.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
ISSUED AT 245 PM EDT SAT MAY 10 2014
ENSEMBLES INDICATE A SLOWLY PROGRESSIVE NATURE TO THE MAIN UPPER
FEATURES DURING THIS PERIOD. A DEEP TROUGH THAT IS EXPECTED TO BE
OVER THE MIDWEST BY THE MIDDLE OF NEXT WEEK WILL GRADUALLY SETTLE
INTO THE GREAT LAKES/OHIO VALLEY BY NEXT WEEKEND.
SOME OF THE ENSEMBLES SUGGEST A SECONDARY WAVE OF LOW PRESSURE MAY
DEVELOP ALONG THE MAIN FRONT TOWARDS THE MIDDLE OF NEXT WEEK WHILE
OTHERS ARE QUICKER WITH THE PASSAGE OF THE FRONT. IN EITHER
CASE...IT APPEARS THE HIGHEST PRECIPITATION THREAT WILL BE TUESDAY
NIGHT INTO WEDNESDAY WITH THE PASSAGE OF THE SURFACE FRONT AND
POTENTIAL SECONDARY WAVE.
AFTER THAT...COOL AND SHOWERY CONDITIONS EXPECTED INTO NEXT WEEKEND
ASSOCIATED WITH THE INSTABILITY NEAR THE DEEP UPPER TROUGH AND ANY
POTENTIAL DISTURBANCES THAT MAY RIPPLE THROUGH IT. WILL KEEP POPS
GOING THROUGHOUT THE EXTENDED PERIOD.
&&
.AVIATION /DISCUSSION FOR 110000Z TAF ISSUANCE/...
ISSUED AT 647 PM EDT SAT MAY 10 2014
SITES WILL START OUT VFR AND DRY WITH NORTHWESTERLY WINDS WITH A
FRONT STALLED NEAR THE OHIO RIVER. THIS WILL SLOWLY LIFT NORTH AS
A WARM FRONT. EXPECT WINDS TO BE LIGHT AND VARIABLE DURING THE
OVERNIGHT BUT PICK UP AGAIN SUNDAY MORNING OUT OF THE SOUTHEAST
AND THEN SOUTH BY SUNDAY AFTERNOON...AROUND 5-8 KTS IN THE MORNING
THEN 8-12 IN THE AFTERNOON.
A COUPLE MODELS ARE SHOWING SOME POTENTIAL FOR CONVECTIVE
DEVELOPMENT DURING THE OVERNIGHT AS WELL...WITH THE BEST CHANCES
AFTER 6Z OR SO. SOME UNCERTAINTY ON HOW THIS WILL PLAY OUT...SO
WILL INCLUDE A BROKEN DECK AT 040 BUT NO PRECIP AT THIS TIME. ALSO
WITH THE FRONT LIFTING NORTH COULD SEE MOISTURE INCREASE AT KBMG
AND THUS SOME POTENTIAL FOR MVFR FOG THERE AND INCLUDED A TEMPO
GROUP AFTER 11Z. MORE CHANCES FOR RAIN AND THUNDER ARE IN THE
FORECAST FOR SUNDAY...BUT UNCERTAINTY IS HIGH ENOUGH TO LEAVE OUT
FOR NOW AND JUST INCLUDE A BROKEN DECK DURING THE AFTERNOON.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...MK
NEAR TERM...RYAN
SHORT TERM...MK
LONG TERM....JAS
AVIATION...CP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
136 PM EDT FRI MAY 9 2014
.SYNOPSIS...
ISSUED AT 358 AM EDT FRI MAY 9 2014
A LOW PRESSURE SYSTEM WILL MOVE NORTHEAST ACROSS THE UPPER GREAT
LAKES TODAY AND ACROSS ONTARIO TONIGHT. A COLD FRONT TRAILING
SOUTH FROM THE LOW WILL MOVE ACROSS OUR AREA THIS AFTERNOON AND
TONIGHT. OCCASIONAL SHOWERS AND THUNDERSTORMS ARE EXPECTED AHEAD
OF THE COLD FRONT TODAY WITH SCATTERED STORMS POSSIBLY LINGERING
INTO THIS EVENING. HIGHS TODAY WILL BE IN THE MID 70S WITH LOWS
TONIGHT RANGING FROM THE UPPER 40S OVER SOUTHWEST MICHIGAN AND
NORTHWEST INDIANA... TO THE UPPER 50S OVER NORTHWEST OHIO.
&&
.UPDATE...
ISSUED AT 1020 AM EDT FRI MAY 9 2014
LINE OF SHOWERS WITH A FEW EMBEDDED THUNDERSTORMS CURRENTLY
APPROACHING THE AREA...ASSOCIATED WITH A WEAK VORT MAX JUST AHEAD OF
THE MAIN SURFACE COLD FRONT. SPC/RAP MESOANALYSIS SHOWS ALMOST NO
INSTABILITY ACROSS NORTHERN INDIANA...EXPLAINING THE LACK OF RECENT
LIGHTNING. EXPECT THIS WILL CONTINUE TO BE THE CASE THROUGH THE
MORNING WITH OVERCAST SKIES AND SOME LIGHT SHOWERS CONTINUING AHEAD
OF THE MAIN LINE. LATEST RAP13 AND HRRR SHOW ONLY A FEW HUNDRED J/KG
OF SBCAPE THROUGH THE EARLY AFTERNOON. SEVERE WEATHER POTENTIAL WITH
THIS ACTIVITY IS VERY LOW BUT A FEW WIND GUSTS AROUND 40MPH AND SOME
SMALL HAIL WILL BE POSSIBLE GIVEN 850MB WINDS OF 40-50 KNOTS AND
RELATIVELY COLD TEMPS ALOFT/LOW FREEZING LEVELS. HI-RES GUIDANCE
INDICATES THE POTENTIAL FOR A SLIGHT RECOVERY IN OUR WEST AND
SOUTHWEST COUNTIES LATER THIS AFTERNOON WITH MIDLEVEL DRY AIR BEHIND
THE INITIAL SHORTWAVE POSSIBLY ALLOWING FOR A FEW PEAKS OF
SUN...SIMILAR TO CURRENT VIS IMAGERY OVER ILLINOIS. WINDOW OF
OPPORTUNITY FOR SEVERE WEATHER WILL BE SMALL THOUGH AND FORECAST
SBCAPES ARE STILL ONLY AROUND 1000 J/KG...LIMITING UPDRAFT STRENGTH.
WILL BE DIFFICULT TO ADEQUATELY DESTABILIZE AFTER THIS MORNING RAIN.
ONCE AGAIN...STRAIGHT LINE WINDS AND SMALL HAIL WOULD BE THE MAIN
THREATS WITH THE BEST CHANCES PROBABLY IN THE 4-8PM TIMEFRAME BUT
THE SEVERE WEATHER THREAT REMAINS HIGHLY CONDITIONAL AT THIS POINT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 348 AM EDT FRI MAY 9 2014
UPR TROF OVER THE PLAINS WILL LIFT NE ACROSS THE GRTLKS AND
DEAMPLIFY TODAY-TNGT. LEAD SHRTWV WILL MOVE ACROSS OUR AREA THIS
MORNING ACCOMPANIED BY A LOW LEVEL THETA-E PLUME/WK INSTABILITY
RESULTING IN WIDESPREAD SHOWERS/TSTMS. MID LEVELS SHOULD DRY OUT IN
WAKE OF THIS LEAD WAVE THIS AFTN... ALLOWING FOR DECREASING
CLOUDINESS AND DESTABILIZATION AS LOW LEVELS REMAIN MOIST AHEAD OF
SFC CDFNT AND APCHG MAIN TROF. NAM SUGGESTS INSTABILITY WILL REACH
AROUND 1500J/KG OVER NRN INDIANA AND SRN MI THIS AFTN WITH 0-6KM
MAINLY UNIDIRECTIONAL SHEAR INCREASING TO AROUND 50KT. THOUGH
FORCING APPEARS FAIRLY WK THIS AFTN AS MOISTURE CONVERGENCE ALONG
CDFNT MINIMAL AND UPR TROF DEAMPLIFING... MODERATE INSTABILITY...
STRONG SHEAR... AND DRY MID LEVELS SUGGEST A POTENTIAL FOR SVR
TSTMS WITH DAMAGING WINDS AND LARGE HAIL... MAINLY ACROSS NRN
INDIANA IF DESTABILIZATION OCCURS AS FCST AND FORCING IS
SUFFICIENT FOR CONVECTION TO DEVELOP DURING PEAK HEATING. CURRENT
TEMPS NEAR PREVIOUS FCST HIGHS FOR TODAY... BUT TEMPS SHOULD RISE
LITTLE THIS MORNING WITH WIDESPREAD SHOWERS MOVG THROUGH AND
CONSIDERABLY COOLER ALOFT THAN YDAY... SO EXPECT HIGHS TODAY
GENERALLY IN THE M70S.
WKNG CDFNT WILL MOVE ACROSS THE AREA TONIGHT PRBLY ACCOMPANIED BY
SCT SHOWERS/TSTMS THIS EVE... WITH CONVECTION DIMINISHING AND MOVG
EAST OVERNIGHT. WK HIGH PRESSURE WILL BUILD INTO THE AREA OVERNIGHT
ALLOWING FOR CLEARING SKIES. SOME PATCHY FOG PSBL ACROSS WRN
PORTIONS OF THE AREA BUT HELD OFF ADDING AT THIS JUNCTURE. TEMPS
WILL BE CONSIDERABLY COOLER WITH LOWS RANGING FROM THE U40S NW TO
THE U50S SE.
&&
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 348 AM EDT FRI MAY 9 2014
LARGE SCALE SUBSIDENCE/DRYING WILL SUPPORT A DRY/COOLER SATURDAY AS
A WEAK AREA OF HIGH PRESSURE BUILDS IN BEHIND FRIDAY NIGHT`S FRONTAL
BOUNDARY. STRENGTHENING SOUTHWEST FLOW IN ADVANCE OF LONGWAVE TROUGH
AMPLIFICATION INTO THE WESTERN US SUNDAY AND HIGH PLAINS EARLY NEXT
WEEK WILL ALLOW GULF MOISTURE TO ADVECT WELL NORTH INTO THE GREAT
LAKES REGION DURING THIS TIME. LOW LEVEL THETA-E GRADIENT/WARM FRONT
IN ADVANCE OF THIS SYSTEM ON LLJ NOSE MAY BRING SOME MAINLY ELEVATED
CONVECTION TO THE AREA (FROM SW TO NE) LATER SATURDAY NIGHT THROUGH
SUNDAY NIGHT...WITH POPS KEPT IN THE LOW/MID CHC RANGE GIVEN THE
ABSENCE OF ANY WELL-DEFINED MID/UPPER LEVEL FORCING.
00Z GUIDANCE CONTINUED THE TREND TOWARD THE SLOWER ECMWF SOLUTION
REGARDING EASTWARD PROGRESSION OF THE UPPER TROUGH NEXT WEEK AS
SYSTEM EVENTUALLY PHASES WITH A CANADIAN PRAIRIES UPPER LOW. THIS
MAY LEAVE THE IWX CWA COMPLETELY IN THE WARM SECTOR BY MONDAY-MONDAY
NIGHT...ALTHOUGH CANNOT RULE OUT PCPN GIVEN MOIST AIRMASS/WEAK
CAPPING AND POTENTIAL FOR WEAK CONVECTIVELY ENHANCED/INDUCED
SHORTWAVES TO LIFT NORTHEAST INTO THE AREA WITHIN SOUTHWEST FLOW.
SHOWER/STORM CHANCES INCREASE AGAIN BY TUESDAY-TUESDAY NIGHT AS
HEIGHT FALLS OVERSPREAD PRE-FRONTAL TROUGH OR COLD FRONT. HELD CLOSE
TO PREV FCST (MID CHC POPS) BUT DID TREND TEMPS UP CLOSER TO WARMER
ECM/MEX MOS AND HPC GUIDANCE MONDAY-TUESDAY. COOLER WX RETURNS
WEDNESDAY INTO THURSDAY IN WAKE OF FRONT.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 136 PM EDT FRI MAY 9 2014
SURFACE COLD FRONT EXTENDING FROM LOW PRESSURE OVER THE NORTHERN
GREAT LAKES IS SLOWLY APPROACHING THE AREA. WEAK LOW LEVEL
CONVERGENCE IN A SUFFICIENTLY MOIST ENVIRONMENT IS SUPPORTING A
FEW SHOWERS ACROSS THE AREA. INSTABILITY HAS BEEN LIMITED BY
MORNING PRECIPITATION AND MOSTLY CLOUDY SKIES THOUGH.
THUNDERSTORMS WILL THEREFORE REMAIN ISOLATED THROUGH THE EVENING.
THERE IS STILL A CHANCE FOR A THUNDERSTORMS TO IMPACT EITHER KSBN
OR KFWA BUT THE PROBABILITY IS TOO LOW AND TIMING IS TOO UNCERTAIN
FOR INCLUSION IN THE TAF. PERIODS OF MVFR CEILINGS WILL BE
POSSIBLE UNTIL FRONT CLEARS THE AREA LATER TONIGHT.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR LMZ043-
046.
&&
$$
UPDATE...AGD
SYNOPSIS...JT
SHORT TERM...JT
LONG TERM...STEINWEDEL
AVIATION...AGD
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AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1020 AM EDT FRI MAY 9 2014
.SYNOPSIS...
ISSUED AT 358 AM EDT FRI MAY 9 2014
A LOW PRESSURE SYSTEM WILL MOVE NORTHEAST ACROSS THE UPPER GREAT
LAKES TODAY AND ACROSS ONTARIO TONIGHT. A COLD FRONT TRAILING
SOUTH FROM THE LOW WILL MOVE ACROSS OUR AREA THIS AFTERNOON AND
TONIGHT. OCCASIONAL SHOWERS AND THUNDERSTORMS ARE EXPECTED AHEAD
OF THE COLD FRONT TODAY WITH SCATTERED STORMS POSSIBLY LINGERING
INTO THIS EVENING. HIGHS TODAY WILL BE IN THE MID 70S WITH LOWS
TONIGHT RANGING FROM THE UPPER 40S OVER SOUTHWEST MICHIGAN AND
NORTHWEST INDIANA... TO THE UPPER 50S OVER NORTHWEST OHIO.
&&
.UPDATE...
ISSUED AT 1020 AM EDT FRI MAY 9 2014
LINE OF SHOWERS WITH A FEW EMBEDDED THUNDERSTORMS CURRENTLY
APPROACHING THE AREA...ASSOCIATED WITH A WEAK VORT MAX JUST AHEAD OF
THE MAIN SURFACE COLD FRONT. SPC/RAP MESOANALYSIS SHOWS ALMOST NO
INSTABILITY ACROSS NORTHERN INDIANA...EXPLAINING THE LACK OF RECENT
LIGHTNING. EXPECT THIS WILL CONTINUE TO BE THE CASE THROUGH THE
MORNING WITH OVERCAST SKIES AND SOME LIGHT SHOWERS CONTINUING AHEAD
OF THE MAIN LINE. LATEST RAP13 AND HRRR SHOW ONLY A FEW HUNDRED J/KG
OF SBCAPE THROUGH THE EARLY AFTERNOON. SEVERE WEATHER POTENTIAL WITH
THIS ACTIVITY IS VERY LOW BUT A FEW WIND GUSTS AROUND 40MPH AND SOME
SMALL HAIL WILL BE POSSIBLE GIVEN 850MB WINDS OF 40-50 KNOTS AND
RELATIVELY COLD TEMPS ALOFT/LOW FREEZING LEVELS. HI-RES GUIDANCE
INDICATES THE POTENTIAL FOR A SLIGHT RECOVERY IN OUR WEST AND
SOUTHWEST COUNTIES LATER THIS AFTERNOON WITH MIDLEVEL DRY AIR BEHIND
THE INITIAL SHORTWAVE POSSIBLY ALLOWING FOR A FEW PEAKS OF
SUN...SIMILAR TO CURRENT VIS IMAGERY OVER ILLINOIS. WINDOW OF
OPPORTUNITY FOR SEVERE WEATHER WILL BE SMALL THOUGH AND FORECAST
SBCAPES ARE STILL ONLY AROUND 1000 J/KG...LIMITING UPDRAFT STRENGTH.
WILL BE DIFFICULT TO ADEQUATELY DESTABILIZE AFTER THIS MORNING RAIN.
ONCE AGAIN...STRAIGHT LINE WINDS AND SMALL HAIL WOULD BE THE MAIN
THREATS WITH THE BEST CHANCES PROBABLY IN THE 4-8PM TIMEFRAME BUT
THE SEVERE WEATHER THREAT REMAINS HIGHLY CONDITIONAL AT THIS POINT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 348 AM EDT FRI MAY 9 2014
UPR TROF OVER THE PLAINS WILL LIFT NE ACROSS THE GRTLKS AND
DEAMPLIFY TODAY-TNGT. LEAD SHRTWV WILL MOVE ACROSS OUR AREA THIS
MORNING ACCOMPANIED BY A LOW LEVEL THETA-E PLUME/WK INSTABILITY
RESULTING IN WIDESPREAD SHOWERS/TSTMS. MID LEVELS SHOULD DRY OUT IN
WAKE OF THIS LEAD WAVE THIS AFTN... ALLOWING FOR DECREASING
CLOUDINESS AND DESTABILIZATION AS LOW LEVELS REMAIN MOIST AHEAD OF
SFC CDFNT AND APCHG MAIN TROF. NAM SUGGESTS INSTABILITY WILL REACH
AROUND 1500J/KG OVER NRN INDIANA AND SRN MI THIS AFTN WITH 0-6KM
MAINLY UNIDIRECTIONAL SHEAR INCREASING TO AROUND 50KT. THOUGH
FORCING APPEARS FAIRLY WK THIS AFTN AS MOISTURE CONVERGENCE ALONG
CDFNT MINIMAL AND UPR TROF DEAMPLIFING... MODERATE INSTABILITY...
STRONG SHEAR... AND DRY MID LEVELS SUGGEST A POTENTIAL FOR SVR
TSTMS WITH DAMAGING WINDS AND LARGE HAIL... MAINLY ACROSS NRN
INDIANA IF DESTABILIZATION OCCURS AS FCST AND FORCING IS
SUFFICIENT FOR CONVECTION TO DEVELOP DURING PEAK HEATING. CURRENT
TEMPS NEAR PREVIOUS FCST HIGHS FOR TODAY... BUT TEMPS SHOULD RISE
LITTLE THIS MORNING WITH WIDESPREAD SHOWERS MOVG THROUGH AND
CONSIDERABLY COOLER ALOFT THAN YDAY... SO EXPECT HIGHS TODAY
GENERALLY IN THE M70S.
WKNG CDFNT WILL MOVE ACROSS THE AREA TONIGHT PRBLY ACCOMPANIED BY
SCT SHOWERS/TSTMS THIS EVE... WITH CONVECTION DIMINISHING AND MOVG
EAST OVERNIGHT. WK HIGH PRESSURE WILL BUILD INTO THE AREA OVERNIGHT
ALLOWING FOR CLEARING SKIES. SOME PATCHY FOG PSBL ACROSS WRN
PORTIONS OF THE AREA BUT HELD OFF ADDING AT THIS JUNCTURE. TEMPS
WILL BE CONSIDERABLY COOLER WITH LOWS RANGING FROM THE U40S NW TO
THE U50S SE.
&&
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 348 AM EDT FRI MAY 9 2014
LARGE SCALE SUBSIDENCE/DRYING WILL SUPPORT A DRY/COOLER SATURDAY AS
A WEAK AREA OF HIGH PRESSURE BUILDS IN BEHIND FRIDAY NIGHT`S FRONTAL
BOUNDARY. STRENGTHENING SOUTHWEST FLOW IN ADVANCE OF LONGWAVE TROUGH
AMPLIFICATION INTO THE WESTERN US SUNDAY AND HIGH PLAINS EARLY NEXT
WEEK WILL ALLOW GULF MOISTURE TO ADVECT WELL NORTH INTO THE GREAT
LAKES REGION DURING THIS TIME. LOW LEVEL THETA-E GRADIENT/WARM FRONT
IN ADVANCE OF THIS SYSTEM ON LLJ NOSE MAY BRING SOME MAINLY ELEVATED
CONVECTION TO THE AREA (FROM SW TO NE) LATER SATURDAY NIGHT THROUGH
SUNDAY NIGHT...WITH POPS KEPT IN THE LOW/MID CHC RANGE GIVEN THE
ABSENCE OF ANY WELL-DEFINED MID/UPPER LEVEL FORCING.
00Z GUIDANCE CONTINUED THE TREND TOWARD THE SLOWER ECMWF SOLUTION
REGARDING EASTWARD PROGRESSION OF THE UPPER TROUGH NEXT WEEK AS
SYSTEM EVENTUALLY PHASES WITH A CANADIAN PRAIRIES UPPER LOW. THIS
MAY LEAVE THE IWX CWA COMPLETELY IN THE WARM SECTOR BY MONDAY-MONDAY
NIGHT...ALTHOUGH CANNOT RULE OUT PCPN GIVEN MOIST AIRMASS/WEAK
CAPPING AND POTENTIAL FOR WEAK CONVECTIVELY ENHANCED/INDUCED
SHORTWAVES TO LIFT NORTHEAST INTO THE AREA WITHIN SOUTHWEST FLOW.
SHOWER/STORM CHANCES INCREASE AGAIN BY TUESDAY-TUESDAY NIGHT AS
HEIGHT FALLS OVERSPREAD PRE-FRONTAL TROUGH OR COLD FRONT. HELD CLOSE
TO PREV FCST (MID CHC POPS) BUT DID TREND TEMPS UP CLOSER TO WARMER
ECM/MEX MOS AND HPC GUIDANCE MONDAY-TUESDAY. COOLER WX RETURNS
WEDNESDAY INTO THURSDAY IN WAKE OF FRONT.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 616 AM EDT FRI MAY 9 2014
SHOWERS WITH SOME EMBEDDED TSTMS EXPECTED TO MOVE ACROSS NRN INDIANA
TODAY. CONDITIONS SHOULD MAINLY BE VFR BUT OCNL MVFR LIKELY DURING
HEAVIER CONVECTION. DRIER AIR IN MID LEVELS WILL SPREAD INTO THE
AREA THIS AFTN RESULTING IN DECREASING CLOUDINESS. TSTMS STILL PSBL
UNTIL WKNG CDFNT MOVES THROUGH THE AREA THIS EVE BUT WITH MAGNITUDE
OF DESTABILIZATION THIS AFTN QUESTIONABLE AND RATHER WK FORCING...
CONTD TO LEAVE TAFS DRY FOR LATE AFTN/EVE. ALTHOUGH LLJ WILL LIFT
NORTH OF THE AREA THIS MORNING... SW WINDS WILL CONT GUSTY AT TIMES
THROUGH THE DAY AS DIURNAL MIXING INCREASES. SOME POTENTIAL FOR BR
DEVELOPMENT OVERNIGHT AS WINDS DIMINISH... ESPECIALLY AT SBN WHERE
POST FRONTAL STRATO CU SHOULD CLEAR OUT LATE... BUT MOISTURE VERY
SHALLOW ON FCST SOUNDINGS SO LEFT MENTION OUT OF TAFS ATTM.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR LMZ043-
046.
&&
$$
UPDATE...AGD
SYNOPSIS...JT
SHORT TERM...JT
LONG TERM...STEINWEDEL
AVIATION...JT
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AREA FORECAST DISCUSSION
NWS DODGE CITY KS
401 PM CDT Fri May 9 2014
...Updated Longterm section...
.SHORT TERM...(This evening through Saturday)
ISSUED AT 313 PM CDT FRI MAY 9 2014
The upper level jet is progged to continue moving east this
afternoon with western Kansas coming under the left exit region of
upper jet this evening. Model soundings from the NAM and RUC13 show
fairly deep mixing with some small elevated CAPE developing along
the Colorado border by late this afternoon. The last few runs of the
HRRR have been consistent in showing isolated showers developing
along the Colorado border and moving into west central and southwest
Kansas for a few hours this evening. Will add this to the grids for
this evening.
As the weak shortwave moves over late tonight, another weak surge of
high pressure will push into southwest Kansas late tonight and early
Saturday. Overnight lows will drop into the mid 40s over west
central Kansas where dewpoints will be lower and winds could go
light for a few hours around sunrise. Low temperatures in south
central Kansas may only drop into the mid 50s where dewpoints are
higher.
During the day Saturday, mid level flow over the central Plains
gradually becomes southwesterly with time as an upper level
shortwave trough digs into the western states. This will result in
surface cyclogenesis over southeast Colorado during the afternoon.
Areas of southwest Kansas along the Oklahoma border should see high
temperatures rising into the upper 80s to near 90 degrees with
southerly winds increasing during the day. This could result in
critical fire weather conditions over far southwest Kansas in the
afternoon.
.LONG TERM...(Saturday night through Friday)
ISSUED AT 349 PM CDT FRI MAY 9 2014
The first issue during this period will be Saturday night. Rich
gulf moisture is not too far southeast, meaning it`s as close as
extreme southeast Oklahoma and north Texas. With the vigorous jet
and upper level anomaly digging into the Rockies, the surface
response will be rapidly falling pressure in the lee of the
Rockies. The surface low should deepen in southeast Colorado.
Boundary layer winds will become east to southeast and the
aforementioned rich moisture will begin stream northwest towards
my forecast area. Warm frontogenesis will take place and this will
advance rapidly north by Saturday night. I see a small opportunity
of elevated and nocturnal convection developing along the nose of
the moisture surge across my far southeast area after dark
Saturday night. Confidence is not high though.
Sunday will be the "warm" day in advance of a strong surge of cold
air that will be sweeping into the plains as the digging system
into the Rockies lifts out into the plains. There should be a
rather tight gradient of temperatures across my area and will
adjust the grids accordingly. With the rich gulf moisture, strong
uvv and surface convergence along the front the chance for
thunderstorms will be high late Sunday and Sunday evening. Behind
the front there should be continued lift and with strong cold air advection there
should be low stratus and at least drizzle, if not light rain.
Monday should be a rather raw day with clouds, blustery winds and
some precipitation. My forecast highs may be a little optimistic
but the trend is to definitely cooler temperatures.
Beyond Monday, the flow will be northwest flow aloft with perhaps
another minor wave sliding southeast which might promote showers
about mid week. Overall temperatures will be below normal seasonal
normals.
&&
.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
ISSUED AT 1220 PM CDT FRI MAY 9 2014
VFR conditions will prevail through this TAF period as high level
moisture will bring a scattered to broken cirrus clouds over the
central High Plains this afternoon and tonight. Southerly winds at
10 to 15 knots this afternoon will diminish tonight and become
light and variable.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 48 85 57 81 / 0 0 10 20
GCK 46 83 51 77 / 10 0 10 10
EHA 47 88 47 78 / 10 0 0 10
LBL 48 89 52 82 / 10 0 10 10
HYS 47 82 56 77 / 0 0 10 10
P28 54 89 68 91 / 0 10 20 40
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...Gerard
LONG TERM...Hutton
AVIATION...Gerard
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
314 PM CDT Fri May 9 2014
...Updated synopsis and short term discussion...
.SYNOPSIS...
ISSUED AT 313 PM CDT FRI MAY 9 2014
This mornings upper air analysis showed a shortwave trough moving
east through the upper Midwest while another shortwave was moving
into the Big Bend region of Texas with more subtle shortwave energy
moving through the central Rockies. Higher up, a 300 millibar jet
was nosing into the Intermountain West. At the surface, a weak low
pressure trough extended south along the eastern slopes of the
Rockies.
&&
.SHORT TERM...(This evening through Saturday)
ISSUED AT 313 PM CDT FRI MAY 9 2014
The upper level jet is progged to continue moving east this
afternoon with western Kansas coming under the left exit region of
upper jet this evening. Model soundings from the NAM and RUC13 show
fairly deep mixing with some small elevated CAPE developing along
the Colorado border by late this afternoon. The last few runs of the
HRRR have been consistent in showing isolated showers developing
along the Colorado border and moving into west central and southwest
Kansas for a few hours this evening. Will add this to the grids for
this evening.
As the weak shortwave moves over late tonight, another weak surge of
high pressure will push into southwest Kansas late tonight and early
Saturday. Overnight lows will drop into the mid 40s over west
central Kansas where dewpoints will be lower and winds could go
light for a few hours around sunrise. Low temperatures in south
central Kansas may only drop into the mid 50s where dewpoints are
higher.
During the day Saturday, mid level flow over the central Plains
gradually becomes southwesterly with time as an upper level
shortwave trough digs into the western states. This will result in
surface cyclogenesis over southeast Colorado during the afternoon.
Areas of southwest Kansas along the Oklahoma border should see high
temperatures rising into the upper 80s to near 90 degrees with
southerly winds increasing during the day. This could result in
critical fire weather conditions over far southwest Kansas in the
afternoon.
.LONG TERM...(Saturday through Thursday)
ISSUED AT 221 AM CDT FRI MAY 9 2014
Models this morning remain in decent agreement with moving an
upper low, which was located off the coast of British Columbia
near 140W at 00z Friday, into the four corners region by early
Sunday. As this next system moves into the southwest United States
early this weekend a trough of low pressure at the surface will
deepen along the lee of the Rockies and temperatures in the 850mb
to 700mb layer will warm. Given the mixing potential suggested by
the latest model soundings, and the 850mb to 700mb temperatures at
00z Sunday the previous forecast still looks on track with highs
in the 80s despite a cold front moving into southwest Kansas late
Saturday. Precipitation chance still appear to be more favorable
north of the interstate 70 corridor given the warm mid level
temperatures forecast over southwestern Kansas Saturday afternoon,
frontal boundary location, where the better forcing from the 850mb
warm air advection, and upper level jet dynamics will be located.
Precipitation chances will increase across western Kansas late
this weekend as the upper level low/trough approaches the Central
High Plains and the elevated mix layer begins to move east. By
Sunday night 850mb to 700mb moisture and frontogenesis will begin
to improve across far western Kansas/eastern Colorado as difluent
flow improves across eastern Colorado and western Kansas near the
nose of an upper level jet that will be ejecting from the base of
the upper level trough. As precipitation chances improves to our
west/northwest...scattered late day convection will be possible
across south central Kansas. This area will be along and east of a
dryline where afternoon CAPE values increase to greater than 2000
j/kg. 0-6km shear and instability suggests severe thunderstorms
will be possible in this area late day. Will therefore include a
mention in the HWO concerning severe potential in south central
Kansas late Sunday.
Afternoon thunderstorms in south central Kansas are forecast to
move east during the evening and the area of thunderstorms
associated with the mid level baroclinic zone begins to spread
into north central and portion of southwest Kansas. Will continue
to favor the higher chances of precipitation Sunday night as this
mid level baroclinic zone spreads east across the western Kansas.
Precipitation chances will taper off as the mid level baroclinic
zone moves east into central Kansas late Monday, however a few
isolated/widely scattered showers/thunderstorms still looks
possible through late day across north central and portions of
west central Kansas given the mid level lapse rates under the
500mb thermal trough. Based on expected cloud cover and 850mb
temperature trends will stay close to the previous forecast for
highs on Monday which were slightly cooler than the latest
guidance.
Monday night into Tuesday as surface high will cross western
Kansas. Based on decreasing wind and clear skies will continue to
favor temperatures cooler guidance for lows Monday night. Tuesday
will be warmer than Monday based on the 850mb temperatures at 00z
Wednesday. Highs on Tuesday will are currently expected to range
from the mid 60s to around 70 degrees.
&&
.AVIATION...(For the 18Z TAFS through 18Z Saturday afternoon)
ISSUED AT 1220 PM CDT FRI MAY 9 2014
VFR conditions will prevail through this TAF period as high level
moisture will bring a scattered to broken cirrus clouds over the
central High Plains this afternoon and tonight. Southerly winds at
10 to 15 knots this afternoon will diminish tonight and become
light and variable.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 48 82 55 81 / 0 0 10 10
GCK 47 81 50 72 / 0 0 10 10
EHA 50 85 50 77 / 0 0 0 10
LBL 48 86 52 80 / 0 0 10 10
HYS 48 80 52 69 / 0 0 10 20
P28 53 86 61 88 / 0 10 10 30
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...Gerard
SHORT TERM...Gerard
LONG TERM...Burgert
AVIATION...Gerard
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1116 AM MDT FRI MAY 9 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 258 AM MDT FRI MAY 9 2014
EARLY MORNING WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS
CONFLUENT FLOW ENTERING ROCKIES OVER PLAINS ON BACK SIDE OF
DEPARTING TROUGH...WITH WEAK SHORTWAVE ENERGY UPSTREAM NEAR DIFLUENT
FLOW OVER GREAT BASIN. AT THE SURFACE HIGH PRESSURE IS IN PLACE OVER
OUR CWA WITH STATIONARY FRONT ALONG FRONT RANGING AND COLD FRONT OVER
OK/TX PANHANDLES. RADAR SHOWS SOME VIRGA AND VERY LIGHT SPRINKLES
LINGERING AS A SHORTWAVE IS EJECTING ACROSS THE SOUTHERLY PLAINS.
WITH SUBSIDENCE BUILDING IN FROM THE NORTH THIS ACTIVITY LIKELY WONT
LAST LONG. TEMPS HAVE DROPPED INTO THE MID 30S ACROSS THE WEST...AND
WE COULD SEE A FEW LOW TEMPS AROUND FREEZING BY SUNRISE.
A WEAK SHORTWAVE TROUGH WILL PASS NORTH OF THE CWA THIS AFTERNOON
AND EVENING AND MAY COMBINE WITH AFTERNOON/EVENING INSTABILITY TO
PRODUCE A FEW THUNDERSTORMS OVER NE COLORADO. VERY DRY LOW LEVELS
WOULD LIMIT PRECIP REACHING THE SURFACE. DECIDED TO KEEP SMALL AREA
OF OUR NW CWA WITH ISO THUNDER AROUND 00Z AND OTHERWISE LIMITED
PRECIP MENTION TO SPRINKLES. SEASONAL TEMPS SHOULD RETURN AS SOUTHERLY
FLOW REDEVELOPS TODAY...WITH HIGHS IN THE 70S AND OVERNIGHT LOWS
TONIGHT IN THE LOW-MID 40S (MAYBE A FEW SPOTS A LITTLE COLDER WEST).
SATURDAY-SUNDAY NIGHT...COMPLICATED FORECAST AS THE NEXT STRONG
UPPER TROUGH IS EXPECTED TO IMPACT THE CENTRAL ROCKIES AND PLAINS.
SOUTHWESTERLY FLOW DEVELOPS ACROSS THE ROCKIES WHICH WOULD
INITIALLY LIMIT ANY SHOWER/THUNDERSTORM CHANCES TO THE NW
SATURDAY. HOWEVER BY SATURDAY NIGHT THE MAIN TROUGH BEGINS TO SLIDE
EAST ALLOWING GOOD MOISTURE AND LIFT OT BUILD OVER THE CWA. BEST
PRECIP CHANCES ACROSS THE CWA STILL LOOKS TO BE ON SUN/SUN NIGHT AND
MODELS SHOW REASONABLE AGREEMENT ON MEASURABLE PRECIP SO I BUMP
POPS INTO 60-70 RANGE FOR THOSE PERIODS. A LITTLE LESS CONFIDENT ON
AREA OF BEST PRECIP...THOUGH PARTS OF THE REGION (ESPECIALLY WEST)
COULD SEE DECENT LIQUID ACCUMULATION WITH THIS EVENT (0.15-0.75").
REGARDING WEATHER TYPE...VERY LIMITED INSTABILITY THROUGH MOST OF THE
EVENT...SO ONLY KEPT THUNDER MENTION SATURDAY AFTERNOON/EVENING.
TEMP PROFILES AND WBZ HEIGHTS WOULD INDICATE A RAIN/SNOW MIX OR A
COMPLETE CHANGEOVER ACROSS THE WESTERN HALF OF THE CWA SUNDAY NIGHT.
WARM GROUND TEMPS MAY LIMIT ANY SNOW ACCUMULATION (ASSUMING LIGHTER
RATES). IN ADDITION TO WARM GROUND TEMPS...CONFIDENCE OF CHANGEOVER
TIMING IS LOW SO I LEFT ACCUMULATION MENTION OUT OF FORECAST. I DID
INCLUDE RAIN/SNOW MENTION AND A BRIEF PERIOD OF ALL SNOW AROUND
SUNRISE EARLY MONDAY MORNING. WILL NEED TO WATCH HOW THIS SYSTEM
EVOLVES TO ZERO IN ON THESE DETAILS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 258 AM MDT FRI MAY 9 2014
MODELS ARE STILL IN DISAGREEMENT WITH THE POSITION AND PROGRESSION
OF THE UPPER LEVEL TROUGH IN THE EXTENDED. GFS STILL MOVES IT
FURTHER EAST MORE QUICKLY THAN THE ECMWF. HOWEVER...THE TROUGH WILL
CONTINUE TO INFLUENCE THE CWA ON MONDAY. TEMPERATURES MONDAY MORNING
APPEAR COLD ENOUGH FOR LIGHT SNOW TO CONTINUE OVER EASTERN COLORADO
WITH A RAIN SNOW MIX IN NORTHWEST KANSAS IN COUNTIES BORDERING
EASTERN COLORADO. TEMPERATURES SHOULD WARM ENOUGH BY 15Z FOR ALL
PRECIPITATION TO BE RAIN...WITH THE CHANCE FOR RAIN CONTINUING
MONDAY AFTERNOON. MONDAY WILL REMAIN BREEZY AS THE TIGHT PRESSURE
GRADIENT STAYS OVER THE CWA UNTIL MONDAY NIGHT WHEN IT RELAXES AND
SURFACE HIGH PRESSURE SETTLES IN OVER COLORADO. TUESDAY THROUGH
WEDNESDAY SHOULD REMAIN DRY AS THE UPPER LEVEL RIDGE OVER THE
WESTERN UNITED STATES BECOMES MORE INFLUENTIAL IN THE HIGH PLAINS.
BY THURSDAY...A SHORTWAVE TROUGH WILL ROTATE AROUND THE UPPER TROUGH
OVER THE GREAT LAKES REGION SENDING A WEAK COLD FRONT THROUGH THE
CWA. SHOWERS AND THUNDERSTORMS COULD DEVELOP AHEAD OF THE
FRONT...SINCE THE GFS DOES HAVE A FEW HUNDRED J/KG OF CAPE OVER
EASTERN COLORADO. AS PREVIOUSLY MENTIONED...THE MODELS ARE HAVING A
HARD TIME COMING TO A CONSENSUS FOR ANY DAY IN THE EXTENDED...SO AM
TRYING TO GET AWAY FROM GETTING TOO DETAILED FOR THUNDERSTORM
POTENTIAL IN DAY 7.
WELL BELOW AVERAGE TEMPERATURES CAN BE EXPECTED TO START OFF THE
EXTENDED PERIOD WITH HIGHS ON MONDAY IN THE LOW TO UPPER 50S. LOWS
MONDAY NIGHT WILL BE IN THE LOW 30S TO LOW 40S WITH HIGHS ON TUESDAY
IN THE LOW TO MID 60S. SLIGHTLY BELOW TO NEAR NORMAL TEMPERATURES
WILL TAKE OVER THROUGH THE REST OF THE EXTENDED WITH HIGHS IN THE
MID 60S TO LOW 70S ON WEDNESDAY AND THURSDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1112 AM MDT FRI MAY 9 2014
VFR EXPECTED THROUGH THE PERIOD AT BOTH KGLD AND KMCK. A FEW
SCATTERED HIGH BASED CU WILL FORM THROUGH THE AFTERNOON AS
CONVECTIVE TEMPERATURES ARE REACHED. HOWEVER SUB CLOUD LAYERS ARE
BONE DRY AND END RESULT WILL ONLY BE VIRGA OR A FEW
SPRINKLES...DISSIPATING AFTER SUNSET. OTHERWISE...A COLD FRONTAL
PASSAGE AROUND SUNRISE SATURDAY MORNING WILL SHIFT SURFACE WINDS
TO NORTHWEST AND THEY WILL BE BREEZY THROUGH SATURDAY MORNING.
&&
.FIRE WEATHER...
ISSUED AT 243 AM MDT FRI MAY 9 2014
WITH WARMER TEMPS AND LOWER TD MIXING TO THE SURFACE WE COULD SEE
RH VALUES WITHIN RFW CRITERIA ACROSS THE SOUTHERN PART OF OUR
FORECAST AREA BOTH TODAY AND SATURDAY AFTERNOON/EARLY EVENING
PERIODS. TODAY WINDS WILL BE WELL BELOW CRITERIA WITH WEAK
GRADIENT IN PLACE...SO NO RFW PRODUCT ANTICIPATED. SW PRESSURE
GRADIENT BEGINS TO INCREASE SATURDAY AHEAD OF DEEPENING UPPER
LOW...THOUGH EVOLUTION OF SURFACE LOW AND FRONT POSITION WILL BE
CRITICAL FOR WHERE WINDS WITHIN RFW CRITERIA WILL CROSS WITH LOW
RH. NOT ENOUGH CONFIDENCE AT THIS POINT TO ISSUE A FIRE WEATHER
WATCH FOR SATURDAY...BUT WE WILL PROBABLY NEED TO MONITOR.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...ALW
AVIATION...024
FIRE WEATHER...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
513 AM MDT FRI MAY 9 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 258 AM MDT FRI MAY 9 2014
EARLY MORNING WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS
CONFLUENT FLOW ENTERING ROCKIES OVER PLAINS ON BACK SIDE OF
DEPARTING TROUGH...WITH WEAK SHORTWAVE ENERGY UPSTREAM NEAR DIFLUENT
FLOW OVER GREAT BASIN. AT THE SURFACE HIGH PRESSURE IS IN PLACE OVER
OUR CWA WITH STATIONARY FRONT ALONG FRONT RANGING AND COLD FRONT OVER
OK/TX PANHANDLES. RADAR SHOWS SOME VIRGA AND VERY LIGHT SPRINKLES
LINGERING AS A SHORTWAVE IS EJECTING ACROSS THE SOUTHERLY PLAINS.
WITH SUBSIDENCE BUILDING IN FROM THE NORTH THIS ACTIVITY LIKELY WONT
LAST LONG. TEMPS HAVE DROPPED INTO THE MID 30S ACROSS THE WEST...AND
WE COULD SEE A FEW LOW TEMPS AROUND FREEZING BY SUNRISE.
A WEAK SHORTWAVE TROUGH WILL PASS NORTH OF THE CWA THIS AFTERNOON
AND EVENING AND MAY COMBINE WITH AFTERNOON/EVENING INSTABILITY TO
PRODUCE A FEW THUNDERSTORMS OVER NE COLORADO. VERY DRY LOW LEVELS
WOULD LIMIT PRECIP REACHING THE SURFACE. DECIDED TO KEEP SMALL AREA
OF OUR NW CWA WITH ISO THUNDER AROUND 00Z AND OTHERWISE LIMITED
PRECIP MENTION TO SPRINKLES. SEASONAL TEMPS SHOULD RETURN AS SOUTHERLY
FLOW REDEVELOPS TODAY...WITH HIGHS IN THE 70S AND OVERNIGHT LOWS
TONIGHT IN THE LOW-MID 40S (MAYBE A FEW SPOTS A LITTLE COLDER WEST).
SATURDAY-SUNDAY NIGHT...COMPLICATED FORECAST AS THE NEXT STRONG
UPPER TROUGH IS EXPECTED TO IMPACT THE CENTRAL ROCKIES AND PLAINS.
SOUTHWESTERLY FLOW DEVELOPS ACROSS THE ROCKIES WHICH WOULD
INITIALLY LIMIT ANY SHOWER/THUNDERSTORM CHANCES TO THE NW
SATURDAY. HOWEVER BY SATURDAY NIGHT THE MAIN TROUGH BEGINS TO SLIDE
EAST ALLOWING GOOD MOISTURE AND LIFT OT BUILD OVER THE CWA. BEST
PRECIP CHANCES ACROSS THE CWA STILL LOOKS TO BE ON SUN/SUN NIGHT AND
MODELS SHOW REASONABLE AGREEMENT ON MEASURABLE PRECIP SO I BUMP
POPS INTO 60-70 RANGE FOR THOSE PERIODS. A LITTLE LESS CONFIDENT ON
AREA OF BEST PRECIP...THOUGH PARTS OF THE REGION (ESPECIALLY WEST)
COULD SEE DECENT LIQUID ACCUMULATION WITH THIS EVENT (0.15-0.75").
REGARDING WEATHER TYPE...VERY LIMITED INSTABILITY THROUGH MOST OF THE
EVENT...SO ONLY KEPT THUNDER MENTION SATURDAY AFTERNOON/EVENING.
TEMP PROFILES AND WBZ HEIGHTS WOULD INDICATE A RAIN/SNOW MIX OR A
COMPLETE CHANGEOVER ACROSS THE WESTERN HALF OF THE CWA SUNDAY NIGHT.
WARM GROUND TEMPS MAY LIMIT ANY SNOW ACCUMULATION (ASSUMING LIGHTER
RATES). IN ADDITION TO WARM GROUND TEMPS...CONFIDENCE OF CHANGEOVER
TIMING IS LOW SO I LEFT ACCUMULATION MENTION OUT OF FORECAST. I DID
INCLUDE RAIN/SNOW MENTION AND A BRIEF PERIOD OF ALL SNOW AROUND
SUNRISE EARLY MONDAY MORNING. WILL NEED TO WATCH HOW THIS SYSTEM
EVOLVES TO ZERO IN ON THESE DETAILS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 258 AM MDT FRI MAY 9 2014
MODELS ARE STILL IN DISAGREEMENT WITH THE POSITION AND PROGRESSION
OF THE UPPER LEVEL TROUGH IN THE EXTENDED. GFS STILL MOVES IT
FURTHER EAST MORE QUICKLY THAN THE ECMWF. HOWEVER...THE TROUGH WILL
CONTINUE TO INFLUENCE THE CWA ON MONDAY. TEMPERATURES MONDAY MORNING
APPEAR COLD ENOUGH FOR LIGHT SNOW TO CONTINUE OVER EASTERN COLORADO
WITH A RAIN SNOW MIX IN NORTHWEST KANSAS IN COUNTIES BORDERING
EASTERN COLORADO. TEMPERATURES SHOULD WARM ENOUGH BY 15Z FOR ALL
PRECIPITATION TO BE RAIN...WITH THE CHANCE FOR RAIN CONTINUING
MONDAY AFTERNOON. MONDAY WILL REMAIN BREEZY AS THE TIGHT PRESSURE
GRADIENT STAYS OVER THE CWA UNTIL MONDAY NIGHT WHEN IT RELAXES AND
SURFACE HIGH PRESSURE SETTLES IN OVER COLORADO. TUESDAY THROUGH
WEDNESDAY SHOULD REMAIN DRY AS THE UPPER LEVEL RIDGE OVER THE
WESTERN UNITED STATES BECOMES MORE INFLUENTIAL IN THE HIGH PLAINS.
BY THURSDAY...A SHORTWAVE TROUGH WILL ROTATE AROUND THE UPPER TROUGH
OVER THE GREAT LAKES REGION SENDING A WEAK COLD FRONT THROUGH THE
CWA. SHOWERS AND THUNDERSTORMS COULD DEVELOP AHEAD OF THE
FRONT...SINCE THE GFS DOES HAVE A FEW HUNDRED J/KG OF CAPE OVER
EASTERN COLORADO. AS PREVIOUSLY MENTIONED...THE MODELS ARE HAVING A
HARD TIME COMING TO A CONSENSUS FOR ANY DAY IN THE EXTENDED...SO AM
TRYING TO GET AWAY FROM GETTING TOO DETAILED FOR THUNDERSTORM
POTENTIAL IN DAY 7.
WELL BELOW AVERAGE TEMPERATURES CAN BE EXPECTED TO START OFF THE
EXTENDED PERIOD WITH HIGHS ON MONDAY IN THE LOW TO UPPER 50S. LOWS
MONDAY NIGHT WILL BE IN THE LOW 30S TO LOW 40S WITH HIGHS ON TUESDAY
IN THE LOW TO MID 60S. SLIGHTLY BELOW TO NEAR NORMAL TEMPERATURES
WILL TAKE OVER THROUGH THE REST OF THE EXTENDED WITH HIGHS IN THE
MID 60S TO LOW 70S ON WEDNESDAY AND THURSDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 512 AM MDT FRI MAY 9 2014
VFR CONDITIONS WILL PREVAIL AT BOTH KGLD AND KMCK TERMINALS
THROUGH THE TAF PERIOD. SW WINDS WILL INCREASE SLIGHTLY TO BE
AROUND 12-15KT DURING THE DAYTIME PERIOD. AFTER SUNSET LIGHT AND
VARIABLE WINDS ARE THEN EXPECTED UNTIL WINDS SHIFT TO THE WEST AND
INCREASE BACK TO THE 10-15KT RANGE BEHIND A QUICK MOVING FRONT.
A FEW THUNDERSTORMS MAY DEVELOP THIS AFTERNOON AND
EVENING AS A WEAK DISTURBANCE MOVES THROUGH THE REGION...HOWEVER
ANY THUNDERSTORM ACTIVITY SHOULD REMAIN WELL NORTHWEST OF BOTH
TERMINALS. THERE COULD STILL BE VIRGA OR EVEN A FEW LIGHT SHOWERS
AT BOTH TERMINALS...HOWEVER CONFIDENCE IS TOO LOW TO INCLUDE VCSH
DURING THIS TAF UPDATE.
&&
.FIRE WEATHER...
ISSUED AT 243 AM MDT FRI MAY 9 2014
WITH WARMER TEMPS AND LOWER TD MIXING TO THE SURFACE
WE COULD SEE RH VALUES WITHIN RFW CRITERIA ACROSS THE SOUTHERN PART
OF OUR FORECAST AREA BOTH TODAY AND SATURDAY AFTERNOON/EARLY EVENING
PERIODS. TODAY WINDS WILL BE WELL BELOW CRITERIA WITH WEAK GRADIENT
IN PLACE...SO NO RFW PRODUCT ANTICIPATED. SW PRESSURE GRADIENT BEGINS
TO INCREASE SATURDAY AHEAD OF DEEPENING UPPER LOW...THOUGH EVOLUTION
OF SURFACE LOW AND FRONT POSITION WILL BE CRITICAL FOR WHERE WINDS
WITHIN RFW CRITERIA WILL CROSS WITH LOW RH. NOT ENOUGH CONFIDENCE AT
THIS POINT TO ISSUE A FIRE WEATHER WATCH FOR SATURDAY...BUT WE WILL
PROBABLY NEED TO MONITOR.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...ALW
AVIATION...DR
FIRE WEATHER...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
302 AM MDT FRI MAY 9 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 258 AM MDT FRI MAY 9 2014
EARLY MORNING WV IMAGERY AND RAP UPPER LEVEL ANALYSIS SHOWS
CONFLUENT FLOW ENTERING ROCKIES OVER PLAINS ON BACK SIDE OF
DEPARTING TROUGH...WITH WEAK SHORTWAVE ENERGY UPSTREAM NEAR DIFLUENT
FLOW OVER GREAT BASIN. AT THE SURFACE HIGH PRESSURE IS IN PLACE OVER
OUR CWA WITH STATIONARY FRONT ALONG FRONT RANGING AND COLD FRONT OVER
OK/TX PANHANDLES. RADAR SHOWS SOME VIRGA AND VERY LIGHT SPRINKLES
LINGERING AS A SHORTWAVE IS EJECTING ACROSS THE SOUTHERLY PLAINS.
WITH SUBSIDENCE BUILDING IN FROM THE NORTH THIS ACTIVITY LIKELY WONT
LAST LONG. TEMPS HAVE DROPPED INTO THE MID 30S ACROSS THE WEST...AND
WE COULD SEE A FEW LOW TEMPS AROUND FREEZING BY SUNRISE.
A WEAK SHORTWAVE TROUGH WILL PASS NORTH OF THE CWA THIS AFTERNOON
AND EVENING AND MAY COMBINE WITH AFTERNOON/EVENING INSTABILITY TO
PRODUCE A FEW THUNDERSTORMS OVER NE COLORADO. VERY DRY LOW LEVELS
WOULD LIMIT PRECIP REACHING THE SURFACE. DECIDED TO KEEP SMALL AREA
OF OUR NW CWA WITH ISO THUNDER AROUND 00Z AND OTHERWISE LIMITED
PRECIP MENTION TO SPRINKLES. SEASONAL TEMPS SHOULD RETURN AS SOUTHERLY
FLOW REDEVELOPS TODAY...WITH HIGHS IN THE 70S AND OVERNIGHT LOWS
TONIGHT IN THE LOW-MID 40S (MAYBE A FEW SPOTS A LITTLE COLDER WEST).
SATURDAY-SUNDAY NIGHT...COMPLICATED FORECAST AS THE NEXT STRONG
UPPER TROUGH IS EXPECTED TO IMPACT THE CENTRAL ROCKIES AND PLAINS.
SOUTHWESTERLY FLOW DEVELOPS ACROSS THE ROCKIES WHICH WOULD
INITIALLY LIMIT ANY SHOWER/THUNDERSTORM CHANCES TO THE NW
SATURDAY. HOWEVER BY SATURDAY NIGHT THE MAIN TROUGH BEGINS TO SLIDE
EAST ALLOWING GOOD MOISTURE AND LIFT OT BUILD OVER THE CWA. BEST
PRECIP CHANCES ACROSS THE CWA STILL LOOKS TO BE ON SUN/SUN NIGHT AND
MODELS SHOW REASONABLE AGREEMENT ON MEASURABLE PRECIP SO I BUMP
POPS INTO 60-70 RANGE FOR THOSE PERIODS. A LITTLE LESS CONFIDENT ON
AREA OF BEST PRECIP...THOUGH PARTS OF THE REGION (ESPECIALLY WEST)
COULD SEE DECENT LIQUID ACCUMULATION WITH THIS EVENT (0.15-0.75").
REGARDING WEATHER TYPE...VERY LIMITED INSTABILITY THROUGH MOST OF THE
EVENT...SO ONLY KEPT THUNDER MENTION SATURDAY AFTERNOON/EVENING.
TEMP PROFILES AND WBZ HEIGHTS WOULD INDICATE A RAIN/SNOW MIX OR A
COMPLETE CHANGEOVER ACROSS THE WESTERN HALF OF THE CWA SUNDAY NIGHT.
WARM GROUND TEMPS MAY LIMIT ANY SNOW ACCUMULATION (ASSUMING LIGHTER
RATES). IN ADDITION TO WARM GROUND TEMPS...CONFIDENCE OF CHANGEOVER
TIMING IS LOW SO I LEFT ACCUMULATION MENTION OUT OF FORECAST. I DID
INCLUDE RAIN/SNOW MENTION AND A BRIEF PERIOD OF ALL SNOW AROUND
SUNRISE EARLY MONDAY MORNING. WILL NEED TO WATCH HOW THIS SYSTEM
EVOLVES TO ZERO IN ON THESE DETAILS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 258 AM MDT FRI MAY 9 2014
MODELS ARE STILL IN DISAGREEMENT WITH THE POSITION AND PROGRESSION
OF THE UPPER LEVEL TROUGH IN THE EXTENDED. GFS STILL MOVES IT
FURTHER EAST MORE QUICKLY THAN THE ECMWF. HOWEVER...THE TROUGH WILL
CONTINUE TO INFLUENCE THE CWA ON MONDAY. TEMPERATURES MONDAY MORNING
APPEAR COLD ENOUGH FOR LIGHT SNOW TO CONTINUE OVER EASTERN COLORADO
WITH A RAIN SNOW MIX IN NORTHWEST KANSAS IN COUNTIES BORDERING
EASTERN COLORADO. TEMPERATURES SHOULD WARM ENOUGH BY 15Z FOR ALL
PRECIPITATION TO BE RAIN...WITH THE CHANCE FOR RAIN CONTINUING
MONDAY AFTERNOON. MONDAY WILL REMAIN BREEZY AS THE TIGHT PRESSURE
GRADIENT STAYS OVER THE CWA UNTIL MONDAY NIGHT WHEN IT RELAXES AND
SURFACE HIGH PRESSURE SETTLES IN OVER COLORADO. TUESDAY THROUGH
WEDNESDAY SHOULD REMAIN DRY AS THE UPPER LEVEL RIDGE OVER THE
WESTERN UNITED STATES BECOMES MORE INFLUENTIAL IN THE HIGH PLAINS.
BY THURSDAY...A SHORTWAVE TROUGH WILL ROTATE AROUND THE UPPER TROUGH
OVER THE GREAT LAKES REGION SENDING A WEAK COLD FRONT THROUGH THE
CWA. SHOWERS AND THUNDERSTORMS COULD DEVELOP AHEAD OF THE
FRONT...SINCE THE GFS DOES HAVE A FEW HUNDRED J/KG OF CAPE OVER
EASTERN COLORADO. AS PREVIOUSLY MENTIONED...THE MODELS ARE HAVING A
HARD TIME COMING TO A CONSENSUS FOR ANY DAY IN THE EXTENDED...SO AM
TRYING TO GET AWAY FROM GETTING TOO DETAILED FOR THUNDERSTORM
POTENTIAL IN DAY 7.
WELL BELOW AVERAGE TEMPERATURES CAN BE EXPECTED TO START OFF THE
EXTENDED PERIOD WITH HIGHS ON MONDAY IN THE LOW TO UPPER 50S. LOWS
MONDAY NIGHT WILL BE IN THE LOW 30S TO LOW 40S WITH HIGHS ON TUESDAY
IN THE LOW TO MID 60S. SLIGHTLY BELOW TO NEAR NORMAL TEMPERATURES
WILL TAKE OVER THROUGH THE REST OF THE EXTENDED WITH HIGHS IN THE
MID 60S TO LOW 70S ON WEDNESDAY AND THURSDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1111 PM MDT THU MAY 8 2014
VFR CONDITIONS WILL PREVAIL AT MCK AND GLD THROUGH THE TAF PERIOD.
LIGHT NORTH TO NORTHWEST WINDS WILL TURN SOUTHWEST BY MORNING WITH
SOME LIGHT GUSTINESS DURING THE AFTERNOON AS THE LEE SURFACE
TROUGH DEEPENS ALONG THE FRONT RANGE.
&&
.FIRE WEATHER...
ISSUED AT 243 AM MDT FRI MAY 9 2014
WITH WARMER TEMPS AND LOWER TD MIXING TO THE SURFACE
WE COULD SEE RH VALUES WITHIN RFW CRITERIA ACROSS THE SOUTHERN PART
OF OUR FORECAST AREA BOTH TODAY AND SATURDAY AFTERNOON/EARLY EVENING
PERIODS. TODAY WINDS WILL BE WELL BELOW CRITERIA WITH WEAK GRADIENT
IN PLACE...SO NO RFW PRODUCT ANTICIPATED. SW PRESSURE GRADIENT BEGINS
TO INCREASE SATURDAY AHEAD OF DEEPENING UPPER LOW...THOUGH EVOLUTION
OF SURFACE LOW AND FRONT POSITION WILL BE CRITICAL FOR WHERE WINDS
WITHIN RFW CRITERIA WILL CROSS WITH LOW RH. NOT ENOUGH CONFIDENCE AT
THIS POINT TO ISSUE A FIRE WEATHER WATCH FOR SATURDAY...BUT WE WILL
PROBABLY NEED TO MONITOR.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...ALW
AVIATION...LOCKHART
FIRE WEATHER...DR
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1202 AM CDT Fri May 9 2014
...UPDATE TO AVIATION...
.SYNOPSIS...
ISSUED AT 1007 PM CDT THU MAY 8 2014
Water vapor imagery and 00Z upper air analysis indicate an upper
level trough axis transitioning eastward across the Western High
Plains. Meanwhile, another upper level trough is pushing ashore into
the Pacific Northwest. Near the surface...a cold front extends from
northeastern Kansas southwest into western Oklahoma while high
pressure builds across the Northern Plains. Cool dry air is
filtering southward into western Kansas with surface dewpoints
falling into the 30s(F).
&&
.SHORT TERM...(This evening through Friday)
ISSUED AT 329 PM CDT THU MAY 8 2014
Chances are greatest that most of the forecast area remains dry
tonight. The front has shifted far enough east that the HRRR model
solutions appear more believable than the NAM model`s solution of a
retreating dryline returning moisture and allowing moist deep
convection. The far west central Kansas counties such as Hamilton
and Stanton could see showers and isolated thunderstorms early this
evening associated with convective development over eastern
Colorado. Of the various HiRes models, the NMM cores suggest a PV
anomaly significant enough to produce showers on the backside of the
upper jet, mainly late tonight and overnight. Instability will be
minimal however and probabilities have been kept very low for the
overnight episode. Temperatures overnight should fall into the low 50s
and seen some 40s farther west where clearing is likely by 12
UTC.
Weak westerly downslope surface winds will develop on Friday as
surface high pressure spreads eastward across southeast Kansas
during the afternoon. Other than mid level clouds, mostly sunny
conditions should prevail based on model layer RH fields. The
downslope flow will promote adiabatic warming resulting in boundary
layer warm advection. Models are strongly aligned for highs in the
mid to upper 70s with only bias corrected solutions creating warmer
highs in the low 80s in the far southwest.
.LONG TERM...(Friday night through Thursday)
ISSUED AT 314 PM CDT THU MAY 8 2014
The medium range models continue to show a strong upper level
shortwave digging into the western states this weekend and moving
out into the plains by early next week. The ECMWF, GEM and UKMET
models have all been similar and tend to be slower and deeper with
this wave. The GFS has been more open and progressive with this wave
for several runs. However, it is showing a tendency in its
operational run...as well as some of the ensemble members...to be a
little slower and deeper.
Upper level westerly flow over the central High Plains on Friday
will gradually become more southwesterly by Saturday night as the
upper wave digs into the Intermountain West. As the upper wave
approaches on Sunday, a frontal boundary should moves southward into
western Kansas with a surface low pressure system developing along
the front. There are some model differences in the position of this
front during the day Sunday. The faster GFS has it through all of
western Kansas by later in the afternoon while the other models keep
it farther west. This will have significant impacts on daytime high
temperatures as well as where the best chance for thunderstorms will
be. Given the model tendencies, will keep the front farther west
with a fairly significant temperature gradient across southwest and
south central Kansas. The models show 60 degree dewpoints spreading
northward into the central Plains ahead of this front. We could see
an outbreak of severe storms along the front during the later
afternoon and early evening hours as stronger southwesterly flow
aloft moves into western Kansas.
Chances for showers and thunderstorms will linger into Monday as the
upper trough continues to move out into the Plains but we should be
drying out by Monday night and Tuesday as the upper wave continues
east. Temperatures in Monday-Wednesday time period will be fairly
cool given the 850 millibar temperatures in the single digits.
Temperatures should moderate through the remainder of the extended
period as upper level heights build over the western and central U.S.
&&
.AVIATION...(For the 06Z TAFS through 06Z Friday night)
ISSUED AT 1200 AM CDT FRI MAY 9 2014
VFR conditions will prevail at all TAF sites through early Friday
evening. As for winds, surface high pressure in the Northern Plains
will sink southward into western Kansas overnight resulting in light
and variable winds across the area. A lee side trough of low
pressure will develop across eastern Colorado early Friday morning
turning winds southwesterly 10 to 20kt by mid day Friday.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 48 82 55 81 / 0 0 10 20
GCK 47 81 50 72 / 0 0 10 10
EHA 50 85 50 77 / 0 0 0 10
LBL 48 86 52 80 / 0 0 10 10
HYS 48 80 52 69 / 0 0 10 20
P28 53 86 61 88 / 0 10 10 30
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...JJohnson
SHORT TERM...Russell
LONG TERM...Gerard
AVIATION...JJohnson
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1141 PM CDT Thu May 8 2014
...AVIATION UPDATE...
.UPDATE...
Issued at 1002 PM CDT THU MAY 8 2014
The cold front has started moving east once again and thunderstorm
development has recommenced, likely due to increased low level
convergence and possibly a weak wave lifting north along the KS/MO
state line. Thinking is that instability has weakened from
previous convection and cooling of the boundary layer. Because of
this we have allowed the watch to expire thinking the chances for
widespread severe weather will continue to diminish as the
boundary layer cools. Latest radar data suggest there could be
some small hail with the stronger updrafts, so we`ll have to
continue monitoring storms for a little while longer.
Latest water vapor imagery continues to show another shortwave now
moving into southwest KS. This wave may help some scattered
showers and thunderstorm activity to form late tonight over east
central KS. Because of this have continued with some chance pops
mainly south of I-70.
UPDATE Issued at 634 PM CDT THU MAY 8 2014
Think the cold front will continue to make steady progress east,
however outflow from recent convection seems to have masked the
true front. The latest RAP and HRRR suggest the stronger
convection could be east of the forecast area by 01Z and have
trended the forecast in this direction. As the front makes clear
progress east, will continue to clear out counties from the watch.
Main hazard remains large hail, although available instability
only around 1000 J/kg seems to be limiting the storms ability to
maintain an updraft. Low level shear parameters do not look very
supportive for much of a tornado threat.
&&
.SHORT TERM...(Through Tonight)
Issued at 252 PM CDT THU MAY 8 2014
The main focus for the short term is on the potential for
thunderstorm development, with some strong to severe storms
possible. Water vapor imagery showed the deep mid-level trough
progressing eastward into the High Plains with a swath of dry air
stretching across the western half of Kansas and the cloud cover
gradually diminishing across eastern Kansas. The main surface low
was situated over eastern Nebraska, with a secondary low developing
over western Oklahoma near the Texas panhandle. As of 19z, the radar
and surface obs showed the cold front stretching between these
surface lows being located generally along a line from Seneca to Alma
to Council Grove. Dewpoints ahead of this boundary where still in
the low/mid 60s, with drier conditions settling in behind the
boundary as dewpoints dropped into the upper 40s to upper 50s across
north central Kansas. The cloud cover along with veering winds
behind the front have limited afternoon heating with temperatures
generally in the 70s.
At 19z, radar showed a few showers and thunderstorms beginning to
initiate along this boundary over far eastern/southeast Nebraska.
Short-range models show this development continuing to spread
southward along the boundary into northeast and eastern Kansas after
20z with more scattered storm development by the 22z-00z time frame,
progressing eastward into Missouri during the evening hours. This
region looks to be favorable for the development of strong to severe
supercell thunderstorms as there is limited convective inhibition in
place. MUCAPE is modest with upwards of 1000-2000 J/kg, and there is
decent 0-6km bulk shear of 50-60kts. With the frontal passage,
soundings show some veering of the low-level winds with 0-1km bulk
shear potentially upwards of 15-20kts, so cannot rule out the
potential for a few isolated tornadoes across far eastern Kansas.
However, the main severe threat looks to be large hail with upwards
of golfball size hail possible with the stronger storms. Could also
see some damaging winds with this activity. These thunderstorms
should initially be somewhat scattered in nature, and develop more
into a line of storms by early this evening as the cold front
progresses eastward, with this main thunderstorm activity
diminishing by mid to late evening. However, additional shower and
thunderstorm develop is possible overnight across east central
Kansas as the secondary low tracks northeastward into southeast
Kansas. Expect these storms to be elevated in nature and should exit
east of the area Friday morning.
Winds will continue to veer to the west and northwest behind the
front tonight into Friday morning, with clearing skies across much
of the northwestern half of the forecast area overnight. As a
result, expect to see a spread in low temperatures tonight ranging
from the middle 40s over north central Kansas to the middle 50s
across east central Kansas due to the lingering shower and
thunderstorm activity.
.LONG TERM...(Friday through Thursday)
Issued at 252 PM CDT THU MAY 8 2014
All indications are that the main PV anomaly/trough axis will exit
the forecast area by around 15Z on Friday with a few lingering
showers or even a thunderstorm possible through that time.
Otherwise, expect downward motion and some dry advection to bring
sunshine by afternoon. The post-frontal airmass is substantially
cooler, but expect to mix up to 850 or even 800 hPa with sunshine
and westerly winds, and still expect highs to climb into the 70s.
Nearly zonal upper flow prevails into early Saturday with the front
weakening and stalling over southern KS or northern OK. Should see
dry conditions through Friday night and much of Saturday but expect
the front to return north with warm moist advection Friday night
into Saturday morning as surface low pressure develops from eastern
Colorado into the OK panhandle. So have gone warmer with Friday
night lows, and also a bit warmer on Saturday as cloud cover should
be limited and the airmass rather warm.
By Saturday afternoon, expect a negatively tilted short wave trough
to eject across the Dakotas. This storm system will have a glancing
impact on the local forecast area, but this bit of ascent will
combine with moderate to strong instability expected by Saturday
afternoon, along with a frontal boundary that will likely be
lingering in the area or drifting back south across parts of Kansas.
Expect the cap to be erased by mid to late afternoon, and the
instability in conjunction with 30 to 50 kts of 0-6 km wind shear
should result in scattered thunderstorms developing near the front.
The most likely area seems to be near/south of I-70 at this time,
and some of these storms would likely take on supercell
characteristics with at least some potential for large hail. The
wind potential will at least partially be tied to how warm
temperatures get in the warm sector...warmer equating to greater
damaging wind potential. Tornado potential seems on the low side
given current forecast parameters given expectation for somewhat
veered low level winds...but with a nearly stationary front in play,
some small potential may exist. Expect a weak embedded short wave
trough to perhaps enhance thunderstorm coverage near and even north
of the front as the low level jet intensifies after sunset. This
could allow the hail threat to persist north of the front through
the overnight hours with elevated convection.
On Sunday, expect a deep upper trough to begin to eject into the
central Plains. The surface low is expected to deepen markedly over
the OK panhandle while the surface front should remain across the
local forecast area. One of the most significant uncertainties in
the Sunday forecast regards the location of the front. The ECMWF is
strongest/farthest north with the surface low and hence has the
front extending across north central KS. The NAM...which can be
flaky with details at the end of the forecast run...is stronger with
the cold front progression and has the boundary along the boundary
by 00Z Monday. The GFS is playing middle ground at this time.
Another area of uncertainty lies in any stabilization that may occur
with any overnight/early morning convection as we`ve seen with
recent events. Wherever the boundary is located by Sunday
afternoon, the warm sector south of the front should be
characterized by strong to extreme instability and ample deep layer
wind shear. Thunderstorms are likely to develop by mid afternoon
along the front and become supercellular and severe. Low level winds
again appear to be veered a bit but still with a fair amount of low
level shear. All told, this appears to be an elevated chance for
severe storms along and south of the frontal boundary...again
focused near/south of I-70 for highest chances. The extent of storm
severity will depend on several factors that can not currently be
resolved but given magnitude of shear and instability the potential
for widespread severe is evident.
Showers and thunderstorms are expected to linger into Monday, with
the end time depending on the speed of the upper trough which
appears to be rather slow in its eastward progression. There are
indications of lingering instability into the day on Monday in
eastern KS but severe potential is questionable and quite low at
this time. The upper low is showing a fair potential to slow and
stall invof the western Great Lakes which would keep the local area
in cool NW flow for several days with a fair amount of cloud cover.
This long term forecast is rather uncertain though as even a minor
eastward shift to the upper low would bring more frequent sunshine
and temps would be quite a bit warmer.
&&
.AVIATION...(For the 06Z TAFs through 06Z Friday Night)
Issued at 1141 PM CDT THU MAY 8 2014
With dryer air moving in behind the front, VFR conditions should
prevail. There is still a wave to the west that should move across
the area bringing some mid level clouds overhead through sunrise.
There could also be some -RA but most guidance is keeping any QPF
south of the terminals so will not mention any precip at this
time.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
UPDATE...Wolters
SHORT TERM...Hennecke
LONG TERM...Barjenbruch
AVIATION...Wolters
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
514 PM EDT Fri May 9 2014
...Updated Aviation Discussion...
.SHORT TERM (Now through Saturday Night)...
Issued at 305 PM EDT Fri May 9 2014
In the near term, rainfall from this morning continues to move NE
but is still hanging in there over east-central KY. The rain will
exit our forecast area in the next 1-2 hrs. Otherwise, conditions
are dry with ample cloud cover over the rest of the region, with
some cumulus clouds now starting to emerge with modest diurnal
warming and decent low-level moisture. Nevertheless, the atmosphere
remains relatively stable at this time, as evidenced by current SPC
mesoanalysis. Thus, expect mainly rain free weather for the next few
hours over central KY and south-central IN as temperatures top out
thru the 70s to around 80 west.
Meanwhile, convection continues to slowly develop along and ahead of
a low-level frontal boundary and confluent zone from southwest IL
into south-central MO. Latest SPC mesoanalysis shows an axis of -4
to -6 surface-based LI values and around 1000 J/kg CAPE in this
axis. All short-range models and the latest HRRR and SPC SREF
suggest this convection will continue to develop and expand E-NE
late this afternoon and evening. Model soundings in our area show
lapse rates increasing late this afternoon and evening, especially
aloft resulting in a more conducive environment in time to develop
and maintain convection within. As a result, will ramp up POPs this
evening, first over south-central IN and northwest KY, then eastward
later tonight.
The best chances for severe storms are to our west in the area of
the current SPC severe thunderstorm watch, enhanced by good
instability and deep-layer speed shear (with a strong upper jet
advancing eastward). As the storms move east later tonight, they may
have a tendency to become slightly elevated with modest nocturnal
cooling over our area. Nevertheless, the boundary layer may stay
adequately mixed to allow some downward momentum transport from the
strongest cells to produce isolated strong or damaging winds, mainly
along and west of the I-65 corridor. After the storms move through,
can`t totally rule out additional scattered showers and isolated
thunderstorms well after midnight and into Saturday morning as a
mid-level shortwave approaches.
During the day Saturday, the shortwave will pass through our area.
This could continue the chance for scattered showers and storms over
eastern and southern forecast area in the morning, but should
effectively clear things out later in the day. As a result, much of
the afternoon should be precipitation free with temperatures rising
through the 70s. If enough sunshine occurs in the afternoon, could
see around 80 or lower 80s in western half of forecast area.
Air mass will begin to destabilize again Saturday afternoon in the
wake of the morning showers, but forcing should be quite limited
in the wake of the morning shortwave. Therefore, expect only
isolated cell redevelopment by late afternoon mainly over western
and northern areas of forecast area. This activity could become a
little more prevalent, especially northern half of forecast area,
Saturday night if a model weak signal of another approaching
shortwave proves correct.
.LONG TERM (Sunday through Friday)...
Issued at 250 PM EDT Fri May 9 2014
The long term period will be fairly active with multiple chances for
showers and thunderstorms. In addition, a big shift in the upper air
pattern will bring much cooler temperatures by the end of the next
work week.
For Sunday through Monday ridging will be building aloft. At the
surface, high pressure will be centered off the east coast.
Southerly winds on the back side of this high pressure will usher in
warm and moist air to the lower Ohio Valley. Temperatures on Sunday
will warm into the lower to mid 80s. Soundings show surface based
instability developing during the afternoon and little to no cap
across the area. However, with the lack of a trigger, storms look to
remain scattered in nature and should mostly dissipate during the
evening hours. For Monday soundings show more of a cap in place, so
rain chances look to be less than Sunday. However, isolated to
scattered showers and storms will still be possible. Highs will be
in the mid 80s.
A cold front will approach and move through the area during the
Tuesday through Wednesday time frame. There is still quite a bit of
discrepancy in the timing of this frontal passage. Thus, have gone
with pops over a wider time frame than is expected with the frontal
passage to account for uncertainty. For now, it looks like
Tuesday/Tuesday night will be the best chance for showers and
storms. However, if slower solutions pan out, chances will linger
into Wednesday.
The timing issue with the front will also have quite an impact on
temperatures mid week as a trough will move in behind this system.
This will usher in cooler air for the end of the week. Highs
Thursday and Friday will be in the lower to mid 60s with lows in the
upper 40s. There may be a slight chance of rain toward the end of
the long term as a weak disturbance moves through the flow aloft,
but timing with these is usually fairly questionable this far out.
&&
.AVIATION (21Z TAF Update)...
Issued at 515 PM EDT Fri May 9 2014
Updated SDF TAF to better time t-storms through the TAF site.
23Z-1Z would be the best time for SDF to see moderate t-storms
causing flight restrictions. Instability and dynamics are lacking
this far east from the current convective line near the IL/IN
border so storms are expected to decrease in intensity as they
move closer to the I-65 corridor.
Issued at 130 PM EDT Fri May 9 2014
Area of showers and isolated thunderstorms continues to progress
east over east-central KY at this time. Conditions are currently VFR
at LEX, but could briefly go MVFR around 1800-1830z with an area of
moderate-to-heavy rain approaching. Otherwise, conditions will
remain VFR at LEX, as well as SDF and BWG this afternoon in the wake
of the rain. Winds this afternoon will remain gusty up to 20 kts
from the S-SW then stay more steady from 5-12 kts tonight.
Then, attention turns to developing thunderstorms over MO near a
frontal boundary. Air mass ahead of these storms will destabilize
resulting in additional development this afternoon. Scattered to
numerous storms could then move into central KY, including SDF and
BWG this evening in the 00-06z time frame. With this in mind, have
indicated a TEMPO group for a few hours for thunderstorms and MVFR
conditions to try to narrow down the best expected time of
occurrence. The expected convection should also reach LEX later
tonight, although probably in a weakening state. Thereafter,
coverage should wane, but can`t rule out isolated or scattered
showers and storms the rest of the night, so have kept VCTS and VCSH
in at all TAFs. On Saturday, could be isolated or scattered showers
around in the morning, with scattered diurnal storms again possible
in vicinity of SDF from 18-00z.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Short Term........TWF
Long Term.........EER
Aviation..........TWF/AMS
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
315 PM EDT Fri May 9 2014
.SHORT TERM (Now through Saturday Night)...
Issued at 305 PM EDT Fri May 9 2014
In the near term, rainfall from this morning continues to move NE
but is still hanging in there over east-central KY. The rain will
exit our forecast area in the next 1-2 hrs. Otherwise, conditions
are dry with ample cloud cover over the rest of the region, with
some cumulus clouds now starting to emerge with modest diurnal
warming and decent low-level moisture. Nevertheless, the atmosphere
remains relatively stable at this time, as evidenced by current SPC
mesoanalysis. Thus, expect mainly rain free weather for the next few
hours over central KY and south-central IN as temperatures top out
thru the 70s to around 80 west.
Meanwhile, convection continues to slowly develop along and ahead of
a low-level frontal boundary and confluent zone from southwest IL
into south-central MO. Latest SPC mesoanalysis shows an axis of -4
to -6 surface-based LI values and around 1000 J/kg CAPE in this
axis. All short-range models and the latest HRRR and SPC SREF
suggest this convection will continue to develop and expand E-NE
late this afternoon and evening. Model soundings in our area show
lapse rates increasing late this afternoon and evening, especially
aloft resulting in a more conducive environment in time to develop
and maintain convection within. As a result, will ramp up POPs this
evening, first over south-central IN and northwest KY, then eastward
later tonight.
The best chances for severe storms are to our west in the area of
the current SPC severe thunderstorm watch, enhanced by good
instability and deep-layer speed shear (with a strong upper jet
advancing eastward). As the storms move east later tonight, they may
have a tendency to become slightly elevated with modest nocturnal
cooling over our area. Nevertheless, the boundary layer may stay
adequately mixed to allow some downward momentum transport from the
strongest cells to produce isolated strong or damaging winds, mainly
along and west of the I-65 corridor. After the storms move through,
can`t totally rule out additional scattered showers and isolated
thunderstorms well after midnight and into Saturday morning as a
mid-level shortwave approaches.
During the day Saturday, the shortwave will pass through our area.
This could continue the chance for scattered showers and storms over
eastern and southern forecast area in the morning, but should
effectively clear things out later in the day. As a result, much of
the afternoon should be precipitation free with temperatures rising
through the 70s. If enough sunshine occurs in the afternoon, could
see around 80 or lower 80s in western half of forecast area.
Air mass will begin to destabilize again Saturday afternoon in the
wake of the morning showers, but forcing should be quite limited
in the wake of the morning shortwave. Therefore, expect only
isolated cell redevelopment by late afternoon mainly over western
and northern areas of forecast area. This activity could become a
little more prevalent, especially northern half of forecast area,
Saturday night if a model weak signal of another approaching
shortwave proves correct.
.LONG TERM (Sunday through Friday)...
Issued at 250 PM EDT Fri May 9 2014
The long term period will be fairly active with multiple chances for
showers and thunderstorms. In addition, a big shift in the upper air
pattern will bring much cooler temperatures by the end of the next
work week.
For Sunday through Monday ridging will be building aloft. At the
surface, high pressure will be centered off the east coast.
Southerly winds on the back side of this high pressure will usher in
warm and moist air to the lower Ohio Valley. Temperatures on Sunday
will warm into the lower to mid 80s. Soundings show surface based
instability developing during the afternoon and little to no cap
across the area. However, with the lack of a trigger, storms look to
remain scattered in nature and should mostly dissipate during the
evening hours. For Monday soundings show more of a cap in place, so
rain chances look to be less than Sunday. However, isolated to
scattered showers and storms will still be possible. Highs will be
in the mid 80s.
A cold front will approach and move through the area during the
Tuesday through Wednesday time frame. There is still quite a bit of
discrepancy in the timing of this frontal passage. Thus, have gone
with pops over a wider time frame than is expected with the frontal
passage to account for uncertainty. For now, it looks like
Tuesday/Tuesday night will be the best chance for showers and
storms. However, if slower solutions pan out, chances will linger
into Wednesday.
The timing issue with the front will also have quite an impact on
temperatures mid week as a trough will move in behind this system.
This will usher in cooler air for the end of the week. Highs
Thursday and Friday will be in the lower to mid 60s with lows in the
upper 40s. There may be a slight chance of rain toward the end of
the long term as a weak disturbance moves through the flow aloft,
but timing with these is usually fairly questionable this far out.
&&
.AVIATION (18Z TAF Update)...
Issued at 130 PM EDT Fri May 9 2014
Area of showers and isolated thunderstorms continues to progress
east over east-central KY at this time. Conditions are currently VFR
at LEX, but could briefly go MVFR around 1800-1830z with an area of
moderate-to-heavy rain approaching. Otherwise, conditions will
remain VFR at LEX, as well as SDF and BWG this afternoon in the wake
of the rain. Winds this afternoon will remain gusty up to 20 kts
from the S-SW then stay more steady from 5-12 kts tonight.
Then, attention turns to developing thunderstorms over MO near a
frontal boundary. Air mass ahead of these storms will destabilize
resulting in additional development this afternoon. Scattered to
numerous storms could then move into central KY, including SDF and
BWG this evening in the 00-06z time frame. With this in mind, have
indicated a TEMPO group for a few hours for thunderstorms and MVFR
conditions to try to narrow down the best expected time of
occurrence. The expected convection should also reach LEX later
tonight, although probably in a weakening state. Thereafter,
coverage should wane, but can`t rule out isolated or scattered
showers and storms the rest of the night, so have kept VCTS and VCSH
in at all TAFs. On Saturday, could be isolated or scattered showers
around in the morning, with scattered diurnal storms again possible
in vicinity of SDF from 18-00z.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Short Term........TWF
Long Term.........EER
Aviation..........TWF
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
145 PM EDT Fri May 9 2014
...Updated Aviation Discussion...
...Forecast Update...
Issued at 1145 AM EDT Fri May 9 2014
Band of showers continues to progress northeast over central KY at
this time. There has not been any thunderstorms in this area so far,
although latest Doppler radar is now showing increasing reflectivity
values over parts of central KY, some expect isolated/scattered
embedded cells early this afternoon as the rain continues pushing
east. The rain will exit our eastern forecast area by 19z or so.
After the rain ends, dry weather should prevail for a few hours this
afternoon over central KY and south-central IN given the absence of
enough forcing and initial instability.
In the wake of this rain, clouds should thin with some breaks of
sun, which should allow temperatures to reach near/around 80 in our
western forecast area. Low-level warming combined with increasing
mid-level lapse rates will increase instability over the lower OH
Valley this afternoon as shown nicely by latest model soundings.
Already, scattered cells are developing in central MO near frontal
zone, although these should move northeast later today and initially
not affect our area. Nevertheless, with increasing instability and
potential diurnal heating boundaries, at least scattered convection
should also develop later this afternoon just to out west and move
into central KY and southern IN late this afternoon/evening.
No major changes to tonight`s forecast at this time.
Issued at 915 AM EDT Fri May 9 2014
An elongated axis of showers with a couple embedded bands of
moderate to heavy rain and possibly an embedded elevated thunder-
storm is moving northeast quickly this morning over west-central KY,
now moving through our western forecast area. 06z model runs along
with latest high-resolution HRRR model show that this axis should
move steadily but coherently through our forecast area for the rest
of this morning into early afternoon, before exiting to our east.
Thus, have raised rainfall probabilities across our entire area.
After this rain passes by, precip will end and then the question
arises about what will happen later this afternoon. Still looks like
some diurnal heating will commence with the atmosphere becoming more
unstable. Models show that scattered convection could develop to our
west this afternoon and then move east into our area later this
afternoon and tonight. This scenario still seems reasonable,
although am not able to pin things down more specifically at this
time yet. Will continue to monitor trends through the day. No
change to temperatures for today at this time. Will evaluate this
later this morning into early afternoon.
Issued at 640 AM EDT Fri May 9 2014
Did a quick update to back off PoPs a bit in the east this morning,
but also increase PoPs slightly across our west and northwestern
areas. Based on latest radar trends, expect a band of showers to
affect portions of southern Indiana and Kentucky west of I-65 this
morning. Expect this activity to diminish in intensity and coverage
as it heads into a slightly drier and more stable airmass. Also
backed off coverage this afternoon a bit given that overall model
solutions are trending a bit drier. Likely PoPs appear to be too
aggressive at this time and have backed them off into the scattered
category. Also bumped temperatures in the west up slightly based on
the assumption of lesser precipitation.
.SHORT TERM (Now through Saturday)...
Issued at 315 AM EDT Fri May 9 2014
In the near term, partly to mostly cloudy skies will be the rule
across southern Indiana and central Kentucky this morning. Early
morning IR imagery shows plenty of high level cloudiness streaming
in from the west. Area radars are rather quiet across central KY
but there are some returns back over southeastern Missouri that are
heading eastward. We expect dry conditions for the remainder of the
early morning hours. Temperatures remain quite mild with readings
generally in the upper 60s to the lower 70s. Some of our cooler
spots appear to have decoupled a bit and are seeing temperatures
down into the upper 50s to around 60. We expect temperatures to
slowly drop a few more degrees before rebounding towards sunrise.
For Today, local and national high resolution modeling suggest area
of convection across southeastern Missouri and northeastern Arkansas
will grow upscale early this morning in response to a moderate
low-level jet axis impinging northeastward into lower Mississippi
Valley. This convection will work eastward during the morning hours
and weaken a bit as it heads into central Kentucky. Persistent
cloud cover and the remnants of this convective activity will likely
keep instability down to marginal levels across the region. That is
not to say that some areas may see stronger convection develop this
afternoon. As the morning convection heads off to the east, we may
see a few breaks develop which could lead to the development of
pockets of higher instability during the afternoon. The best
chances of this occurring would be out across the western areas.
Overall, we still do not believe today will be a total washout.
Though areas that do receive rain could get a nice soaking as the
showers and storms move through the region. Highs today look to
range from the middle to upper 70s in the west with upper 70s to
lower 80s in the east.
As we move into the evening hours, the higher resolution models do
show a secondary line of storms forming along the frontal boundary
approaching from the northwest. These storms probably will fire
along a line from Indianapolis to St. Louis early this evening and
then spread eastward into our region during the overnight period.
Depending on how fast the early morning activity clears the region
will be a determining factor in how strong the evening/overnight
convection will be. With the line expected to come through at the
time of minimum heating, we are not overly impressed with severe
potential. Strong storms are certainly possible with damaging winds
and hail being the primary threats. The activity should clear our
region by early Saturday morning with temperatures only cooling into
the mid-upper 60s.
For Saturday, skies will likely start off mostly cloudy and then
begin to clear from the west towards the east. While the upper flow
takes on more of zonal pattern, there is difficulty in determining
any real triggers for convection. Isolated-scattered convection
will be possible with the highest concentration out toward the
eastern portions of the forecast area. Though, by and large most
areas will probably see mainly dry conditions. Highs for Saturday
will be largely dependent on cloud cover during the afternoon. The
multi-model consensus suggests highs in the upper 70s to near 80 in
the west with mainly mid-upper 70s in the east.
.LONG TERM (Saturday Night through Thursday)...
Issued at 319 PM EDT Thu May 8 2014
As previously advertised, the Ohio Valley will be entering into an
active pattern with showers and thunderstorms in the forecast for
nearly every day in this period. Synoptically, Saturday will undergo
a transition to more zonal at the 500mb level as the disturbance
that brings rain to the region Friday night moves off toward the
east. The forecast challenge for Saturday is how quickly the storms
exit the forecast area as the deterministic models are struggling to
come into better agreement. The trend has been just a bit slower, as
evident from comparing previous runs with the 12Z runs. The NAM has
been the quickest and conversely, the GFS messy and the slowest. The
09Z SREF seems to be the better compromise and have leaned toward it
to show a general partial clearing from west to east throughout the
day.
Through the remainder of the weekend, much of Saturday night should
be dry before the atmosphere recharges ahead of the next system.
We`ll remain under southerly flow with high pressure centered over
the Atlantic, allowing for GoMex moisture to pool into the region.
Under this warm , moist air advection regime, Sunday`s forecast is
also a bit tricky as we could see some sporadic storms firing up,
especially with diurnal heating throughout the day. There is no
obvious signal for which portions of the forecast area will see
better rain chances than others given this type of setup so have
broad brushed low-end chance PoPs throughout. After the sun sets on
Sunday, should see a wane in storm coverage with the loss of the
aforementioned heating. Something to watch for, however, is that the
12Z NAM is hinting at a mesoscale convective system to build across
eastern KS/central MO and race off into the Great Lakes region late
Saturday night through Sunday. This is in response to a surface low
that develops just behind it. The NAM is depicting the eastern
portion of this system to break off and jet across central KY before
dying out as it loses its forcing mechanism. We`ll have to see how
this evolves as we approach that time frame.
As if the models haven`t been struggling enough, true temporal
divergence becomes evident early next week as an amplified pattern
sets up: troughing across the Plains and ridging over the East
Coast. The GFS has been consistently fast with the ECMWF much
slower. Have attempted to blend and compromise between the two,
coming to the uncertain conclusion that Tuesday looks to be the best
chance for active weather across the area. One thing the models do
agree on is the pattern change coming by the middle to end of next
week.
Given the unsettled nature of the upcoming pattern, temperature
forecasts will be difficult to nail down with certainty, with clouds
potentially wrecking havoc on the highs/lows. However, taking into
consideration the type of airmasses we`ll be under, along with climo
for this time of year, the warmest days of the long-term period will
be Sunday and Monday, with Saturday and Tuesday being slightly
cooler, and Wednesday onward dropping well below normal. This
forecast update will show highs in the upper 70s on Saturday as
clouds and precip exit; highs in the lower 80s Sunday - Monday under
southerly flow/WAA; Tuesday in the mid to upper 70s with stormy
conditions; and 60s Wednesday - Thursday. Look for lows to respond
accordingly with 60s Saturday night - Monday night and flirting with
the 50 degree mark Tuesday night - Wednesday night.
&&
.AVIATION (18Z TAF Update)...
Issued at 130 PM EDT Fri May 9 2014
Area of showers and isolated thunderstorms continues to progress
east over east-central KY at this time. Conditions are currently VFR
at LEX, but could briefly go MVFR around 1800-1830z with an area of
moderate-to-heavy rain approaching. Otherwise, conditions will
remain VFR at LEX, as well as SDF and BWG this afternoon in the wake
of the rain. Winds this afternoon will remain gusty up to 20 kts
from the S-SW then stay more steady from 5-12 kts tonight.
Then, attention turns to developing thunderstorms over MO near a
frontal boundary. Air mass ahead of these storms will destabilize
resulting in additional development this afternoon. Scattered to
numerous storms could then move into central KY, including SDF and
BWG this evening in the 00-06z time frame. With this in mind, have
indicated a TEMPO group for a few hours for thunderstorms and MVFR
conditions to try to narrow down the best expected time of
occurrence. The expected convection should also reach LEX later
tonight, although probably in a weakening state. Thereafter,
coverage should wane, but can`t rule out isolated or scattered
showers and storms the rest of the night, so have kept VCTS and VCSH
in at all TAFs. On Saturday, could be isolated or scattered showers
around in the morning, with scattered diurnal storms again possible
in vicinity of SDF from 18-00z.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........TWF
Short Term.....MJ
Long Term......BJS
Aviation.......TWF
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1118 AM CDT Fri May 9 2014
.MESOSCALE DISCUSSION...
Issued at 1117 AM CDT FRI MAY 9 2014
The explicit convection producing guidance, 3km HRRR, as well as
the 13km RUC is doing a fairly decent job of depicting the
departing and new convective activity in Missouri as of 16z
Friday. WFO LSX noted that pea (1/4") hail was reported near
Steelville MO in the axis of 600+ CAPE. This axis should continue
to translate eastward and increase to between 1000-1500 J/KG per
the 13km RUC between 17z-20z. Mid-level winds are a little
stronger than forecast between 700mb-500 mb which may accelerate
the timing and cooling aloft with the storms as they move through
Southeast Missouri and Southern Illinois. If the convection can
tap the stronger mid-level shear enough to enhance updrafts,
larger than dime/quarter size hail may be a real possibility. The
GOES Sounder Water Vapor difference channels 7.0 micron (sensitive
near 700 mb) and 7.4 micron (sensitive near 850 mb) suggesting a
sharp drying aloft moving from Oklahoma into Southwest MO ast of
1447z today. This may sharpen updraft with sharper lapse rates aloft as
storms move near the Carter to Perry County MO county western
borders, into Perry and Jackson IL county later this afternoon.
Upper level support has been forecast to be more persistent over
Southern IL...mainly between Interstate 64 corridor and Route 13,
so would not be surprised to see more robust updrafts, producing
severe hail and damaging wind gusts in that area for a more
prolonged period. Still could see some good storms in Southeast
Missouri as well as the afternoon progresses.
As we get into late evening, between 10 pm-11 pm CDT...could see
flow transition into a more repeating shower or thunderstorm
concern...with training of echoes fore more overnight persistent
rain along and mainly south of the Ohio River, but including
Southwest Indiana and the delta region of Southeast Missouri, just
north of the Bootheel.
&&
.UPDATE...
Issued at 1117 AM CDT FRI MAY 9 2014
Interim morning update to reflect marked changes in PoP, weather,
sky cover, and temperature/dewpoint to reflect recharging of
atmosphere between early morning MCS and new convective activity
on central and southern Missouri.
&&
.SHORT TERM...(Today through Sunday night)
Issued at 234 AM CDT FRI MAY 9 2014
With the approach of a frontal system and attendant H5 trough,
shower and thunderstorm activity will increase from west to east
across the region today. With the flow aloft nearly parallel to the
front combined with surface high pressure firmly planted over the
southeast US, the front will have difficulty making it too far east
over the next 18 to 24 hours.
Latest guidance shows the front moving into the western sections of
our CWA this afternoon, becoming quasi-stationary over the northern
sections by Saturday morning, then lifting back to the north as a
warm front on Saturday. With the front forecast to be in the
vicinity, precipitation chances are greatest today and tonight.
There is a slight risk of a few storms becoming severe this
afternoon with large hail and damaging winds being the main hazards.
Precipitation forecast confidence rather low Saturday, Saturday
night, and Sunday as our area will be in the warm sector and mid
level temperatures not that impressive. Low level forcing will be
negligible but ripples of mid level energy will continue to track
across left-over deep moisture, and models not in the best agreement
on where the moisture will be.
Sunday night as the next weather system takes shape over the plains,
the flow aloft turns more southwest forcing the ridging over the
southeast to build northwest into our neck of the woods. This should
limit any precipitation chances to the far northwestern and western
sections of our CWA.
Temperatures will stay at or above normal through the period.
.LONG TERM...(Monday through Thursday night)
Issued at 234 AM CDT FRI MAY 9 2014
To start out the long term period, we will be watching the evolution
of an upper trough that will be positioned in the Rockies on Monday.
As this feature slowly moves east, a sfc frontal boundary will be
making its way toward the region. It is looking more and more that
Monday might end up being dry as we wait for the incoming front.
Best chances late in the day will be in parts of southeast MO and
southern IL. There continues to be timing issues between the GFS and
ECMWF, with the GFS continuing to be the faster model but looking
back on previous runs, both models have slowed down a bit with
timing. The ECMWF seems to keep a much stronger upper high in place
over the southeastern states which slows down the progression of the
aforementioned upper trough.
The 12Z ECMWF barely has the front into the area by 12Z Tuesday,
with precip knocking on our western door, while the 00Z GFS is
showing a pretty stormy Monday night period going into Tuesday. The
00Z ECMWF is a bit faster but still not as fast as the GFS. The
front continues to move east during the day on Tuesday and plan on
keeping likely pops right now as there seems to be good consistency
for that day so far. When to exit the precipitation though, will be
another story. The 00Z GFS moves the activity out of the area
Tuesday night while the slower ECMWF takes until Wednesday morning
to dry us out. Plus, the 00Z ECMWF indicates another wave of
precipitation coincident with the main upper trough as it moves
through Tuesday night into early Wednesday.
These timing issues also play a big role in determining
temperatures. The faster GFS is indicating that the colder air will
filter in as early as Tuesday, making for a much cooler day than the
slower ECMWF would suggest. Wednesday`s temps though will be a bit
easier since we should have the colder air mass into the area by
then. With 850 mb temps in the single digits, we will definitely
feel like fall has returned briefly, as we struggle to get out of
the 60s in some places. Looking at some of the CIPS analog guidance,
there is even more confidence that highs in the 60s appear likely
with this colder air mass coming in. Highs in Thursday will be even
more of a challenge since the GFS turns winds around to southerly,
which warms us up, but the ECMWF maintains a colder northwest
wind.
&&
.AVIATION...
Issued at 642 AM CDT FRI MAY 9 2014
At KCGI/KPAH MVFR cigs/vsbys possible between 20-02Z in TSRA...
otherwise VFR. At KEVV/KOWB MVFR cigs/vsbys in TSRA between
12-16Z, then again between 23-04Z...otherwise VFR. Southerly winds
aob 10 knots early should increase to 10-12 knots with gusts up
to 18-20 knotsafter 15Z, then drop back to aob 10 knots after 00Z.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
MESOSCALE...Smith
UPDATE...Smith
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1153 AM EDT Fri May 9 2014
...Forecast Update...
Issued at 1145 AM EDT Fri May 9 2014
Band of showers continues to progress northeast over central KY at
this time. There has not been any thunderstorms in this area so far,
although latest Doppler radar is now showing increasing reflectivity
values over parts of central KY, some expect isolated/scattered
embedded cells early this afternoon as the rain continues pushing
east. The rain will exit our eastern forecast area by 19z or so.
After the rain ends, dry weather should prevail for a few hours this
afternoon over central KY and south-central IN given the absence of
enough forcing and initial instability.
In the wake of this rain, clouds should thin with some breaks of
sun, which should allow temperatures to reach near/around 80 in our
western forecast area. Low-level warming combined with increasing
mid-level lapse rates will increase instability over the lower OH
Valley this afternoon as shown nicely by latest model soundings.
Already, scattered cells are developing in central MO near frontal
zone, although these should move northeast later today and initially
not affect our area. Nevertheless, with increasing instability and
potential diurnal heating boundaries, at least scattered convection
should also develop later this afternoon just to out west and move
into central KY and southern IN late this afternoon/evening.
No major changes to tonight`s forecast at this time.
Issued at 915 AM EDT Fri May 9 2014
An elongated axis of showers with a couple embedded bands of
moderate to heavy rain and possibly an embedded elevated thunder-
storm is moving northeast quickly this morning over west-central KY,
now moving through our western forecast area. 06z model runs along
with latest high-resolution HRRR model show that this axis should
move steadily but coherently through our forecast area for the rest
of this morning into early afternoon, before exiting to our east.
Thus, have raised rainfall probabilities across our entire area.
After this rain passes by, precip will end and then the question
arises about what will happen later this afternoon. Still looks like
some diurnal heating will commence with the atmosphere becoming more
unstable. Models show that scattered convection could develop to our
west this afternoon and then move east into our area later this
afternoon and tonight. This scenario still seems reasonable,
although am not able to pin things down more specifically at this
time yet. Will continue to monitor trends through the day. No
change to temperatures for today at this time. Will evaluate this
later this morning into early afternoon.
Issued at 640 AM EDT Fri May 9 2014
Did a quick update to back off PoPs a bit in the east this morning,
but also increase PoPs slightly across our west and northwestern
areas. Based on latest radar trends, expect a band of showers to
affect portions of southern Indiana and Kentucky west of I-65 this
morning. Expect this activity to diminish in intensity and coverage
as it heads into a slightly drier and more stable airmass. Also
backed off coverage this afternoon a bit given that overall model
solutions are trending a bit drier. Likely PoPs appear to be too
aggressive at this time and have backed them off into the scattered
category. Also bumped temperatures in the west up slightly based on
the assumption of lesser precipitation.
.SHORT TERM (Now through Saturday)...
Issued at 315 AM EDT Fri May 9 2014
In the near term, partly to mostly cloudy skies will be the rule
across southern Indiana and central Kentucky this morning. Early
morning IR imagery shows plenty of high level cloudiness streaming
in from the west. Area radars are rather quiet across central KY
but there are some returns back over southeastern Missouri that are
heading eastward. We expect dry conditions for the remainder of the
early morning hours. Temperatures remain quite mild with readings
generally in the upper 60s to the lower 70s. Some of our cooler
spots appear to have decoupled a bit and are seeing temperatures
down into the upper 50s to around 60. We expect temperatures to
slowly drop a few more degrees before rebounding towards sunrise.
For Today, local and national high resolution modeling suggest area
of convection across southeastern Missouri and northeastern Arkansas
will grow upscale early this morning in response to a moderate
low-level jet axis impinging northeastward into lower Mississippi
Valley. This convection will work eastward during the morning hours
and weaken a bit as it heads into central Kentucky. Persistent
cloud cover and the remnants of this convective activity will likely
keep instability down to marginal levels across the region. That is
not to say that some areas may see stronger convection develop this
afternoon. As the morning convection heads off to the east, we may
see a few breaks develop which could lead to the development of
pockets of higher instability during the afternoon. The best
chances of this occurring would be out across the western areas.
Overall, we still do not believe today will be a total washout.
Though areas that do receive rain could get a nice soaking as the
showers and storms move through the region. Highs today look to
range from the middle to upper 70s in the west with upper 70s to
lower 80s in the east.
As we move into the evening hours, the higher resolution models do
show a secondary line of storms forming along the frontal boundary
approaching from the northwest. These storms probably will fire
along a line from Indianapolis to St. Louis early this evening and
then spread eastward into our region during the overnight period.
Depending on how fast the early morning activity clears the region
will be a determining factor in how strong the evening/overnight
convection will be. With the line expected to come through at the
time of minimum heating, we are not overly impressed with severe
potential. Strong storms are certainly possible with damaging winds
and hail being the primary threats. The activity should clear our
region by early Saturday morning with temperatures only cooling into
the mid-upper 60s.
For Saturday, skies will likely start off mostly cloudy and then
begin to clear from the west towards the east. While the upper flow
takes on more of zonal pattern, there is difficulty in determining
any real triggers for convection. Isolated-scattered convection
will be possible with the highest concentration out toward the
eastern portions of the forecast area. Though, by and large most
areas will probably see mainly dry conditions. Highs for Saturday
will be largely dependent on cloud cover during the afternoon. The
multi-model consensus suggests highs in the upper 70s to near 80 in
the west with mainly mid-upper 70s in the east.
.LONG TERM (Saturday Night through Thursday)...
Issued at 319 PM EDT Thu May 8 2014
As previously advertised, the Ohio Valley will be entering into an
active pattern with showers and thunderstorms in the forecast for
nearly every day in this period. Synoptically, Saturday will undergo
a transition to more zonal at the 500mb level as the disturbance
that brings rain to the region Friday night moves off toward the
east. The forecast challenge for Saturday is how quickly the storms
exit the forecast area as the deterministic models are struggling to
come into better agreement. The trend has been just a bit slower, as
evident from comparing previous runs with the 12Z runs. The NAM has
been the quickest and conversely, the GFS messy and the slowest. The
09Z SREF seems to be the better compromise and have leaned toward it
to show a general partial clearing from west to east throughout the
day.
Through the remainder of the weekend, much of Saturday night should
be dry before the atmosphere recharges ahead of the next system.
We`ll remain under southerly flow with high pressure centered over
the Atlantic, allowing for GoMex moisture to pool into the region.
Under this warm , moist air advection regime, Sunday`s forecast is
also a bit tricky as we could see some sporadic storms firing up,
especially with diurnal heating throughout the day. There is no
obvious signal for which portions of the forecast area will see
better rain chances than others given this type of setup so have
broad brushed low-end chance PoPs throughout. After the sun sets on
Sunday, should see a wane in storm coverage with the loss of the
aforementioned heating. Something to watch for, however, is that the
12Z NAM is hinting at a mesoscale convective system to build across
eastern KS/central MO and race off into the Great Lakes region late
Saturday night through Sunday. This is in response to a surface low
that develops just behind it. The NAM is depicting the eastern
portion of this system to break off and jet across central KY before
dying out as it loses its forcing mechanism. We`ll have to see how
this evolves as we approach that time frame.
As if the models haven`t been struggling enough, true temporal
divergence becomes evident early next week as an amplified pattern
sets up: troughing across the Plains and ridging over the East
Coast. The GFS has been consistently fast with the ECMWF much
slower. Have attempted to blend and compromise between the two,
coming to the uncertain conclusion that Tuesday looks to be the best
chance for active weather across the area. One thing the models do
agree on is the pattern change coming by the middle to end of next
week.
Given the unsettled nature of the upcoming pattern, temperature
forecasts will be difficult to nail down with certainty, with clouds
potentially wrecking havoc on the highs/lows. However, taking into
consideration the type of airmasses we`ll be under, along with climo
for this time of year, the warmest days of the long-term period will
be Sunday and Monday, with Saturday and Tuesday being slightly
cooler, and Wednesday onward dropping well below normal. This
forecast update will show highs in the upper 70s on Saturday as
clouds and precip exit; highs in the lower 80s Sunday - Monday under
southerly flow/WAA; Tuesday in the mid to upper 70s with stormy
conditions; and 60s Wednesday - Thursday. Look for lows to respond
accordingly with 60s Saturday night - Monday night and flirting with
the 50 degree mark Tuesday night - Wednesday night.
&&
.AVIATION (12Z TAF Update)...
Issued at 635 AM EDT Fri May 9 2014
A surface cold front will push eastward toward the region today.
Abundant high cloud cover will continue to advect eastward across
the terminals today producing high ceilings. Scattered showers over
western KY will continue to move east and may affect KSDF and KBWG
by mid to late morning. Stronger aviation concern that will emerge
this morning will be the increase in southwesterly winds at the
terminals. We expect winds to pick up around 09/14Z or so with
sustained winds of 12-16kts and gusts up to 20kts. Scattered
convection is expected to further develop this afternoon and evening
as the frontal boundary gets closer to the region. VFR conditions
are expected to prevail at the terminals, but some temporary MVFR
cigs within passing convection will be possible. Overall convective
coverage should diminish toward sunset, but a secondary line of
convection may develop out to the west and affect the terminals
after 10/02Z.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........TWF
Short Term.....MJ
Long Term......BJS
Aviation.......MJ
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
926 AM EDT Fri May 9 2014
...Forecast Update...
Issued at 915 AM EDT Fri May 9 2014
An elongated axis of showers with a couple embedded bands of
moderate to heavy rain and possibly an embedded elevated thunder-
storm is moving northeast quickly this morning over west-central KY,
now moving through our western forecast area. 06z model runs along
with latest high-resolution HRRR model show that this axis should
move steadily but coherently through our forecast area for the rest
of this morning into early afternoon, before exiting to our east.
Thus, have raised rainfall probabilities across our entire area.
After this rain passes by, precip will end and then the question
arises about what will happen later this afternoon. Still looks like
some diurnal heating will commence with the atmosphere becoming more
unstable. Models show that scattered convection could develop to our
west this afternoon and then move east into our area later this
afternoon and tonight. This scenario still seems reasonable,
although am not able to pin things down more specifically at this
time yet. Will continue to monitor trends through the day. No
change to temperatures for today at this time. Will evaluate this
later this morning into early afternoon.
Issued at 640 AM EDT Fri May 9 2014
Did a quick update to back off PoPs a bit in the east this morning,
but also increase PoPs slightly across our west and northwestern
areas. Based on latest radar trends, expect a band of showers to
affect portions of southern Indiana and Kentucky west of I-65 this
morning. Expect this activity to diminish in intensity and coverage
as it heads into a slightly drier and more stable airmass. Also
backed off coverage this afternoon a bit given that overall model
solutions are trending a bit drier. Likely PoPs appear to be too
aggressive at this time and have backed them off into the scattered
category. Also bumped temperatures in the west up slightly based on
the assumption of lesser precipitation.
.SHORT TERM (Now through Saturday)...
Issued at 315 AM EDT Fri May 9 2014
In the near term, partly to mostly cloudy skies will be the rule
across southern Indiana and central Kentucky this morning. Early
morning IR imagery shows plenty of high level cloudiness streaming
in from the west. Area radars are rather quiet across central KY
but there are some returns back over southeastern Missouri that are
heading eastward. We expect dry conditions for the remainder of the
early morning hours. Temperatures remain quite mild with readings
generally in the upper 60s to the lower 70s. Some of our cooler
spots appear to have decoupled a bit and are seeing temperatures
down into the upper 50s to around 60. We expect temperatures to
slowly drop a few more degrees before rebounding towards sunrise.
For Today, local and national high resolution modeling suggest area
of convection across southeastern Missouri and northeastern Arkansas
will grow upscale early this morning in response to a moderate
low-level jet axis impinging northeastward into lower Mississippi
Valley. This convection will work eastward during the morning hours
and weaken a bit as it heads into central Kentucky. Persistent
cloud cover and the remnants of this convective activity will likely
keep instability down to marginal levels across the region. That is
not to say that some areas may see stronger convection develop this
afternoon. As the morning convection heads off to the east, we may
see a few breaks develop which could lead to the development of
pockets of higher instability during the afternoon. The best
chances of this occurring would be out across the western areas.
Overall, we still do not believe today will be a total washout.
Though areas that do receive rain could get a nice soaking as the
showers and storms move through the region. Highs today look to
range from the middle to upper 70s in the west with upper 70s to
lower 80s in the east.
As we move into the evening hours, the higher resolution models do
show a secondary line of storms forming along the frontal boundary
approaching from the northwest. These storms probably will fire
along a line from Indianapolis to St. Louis early this evening and
then spread eastward into our region during the overnight period.
Depending on how fast the early morning activity clears the region
will be a determining factor in how strong the evening/overnight
convection will be. With the line expected to come through at the
time of minimum heating, we are not overly impressed with severe
potential. Strong storms are certainly possible with damaging winds
and hail being the primary threats. The activity should clear our
region by early Saturday morning with temperatures only cooling into
the mid-upper 60s.
For Saturday, skies will likely start off mostly cloudy and then
begin to clear from the west towards the east. While the upper flow
takes on more of zonal pattern, there is difficulty in determining
any real triggers for convection. Isolated-scattered convection
will be possible with the highest concentration out toward the
eastern portions of the forecast area. Though, by and large most
areas will probably see mainly dry conditions. Highs for Saturday
will be largely dependent on cloud cover during the afternoon. The
multi-model consensus suggests highs in the upper 70s to near 80 in
the west with mainly mid-upper 70s in the east.
.LONG TERM (Saturday Night through Thursday)...
Issued at 319 PM EDT Thu May 8 2014
As previously advertised, the Ohio Valley will be entering into an
active pattern with showers and thunderstorms in the forecast for
nearly every day in this period. Synoptically, Saturday will undergo
a transition to more zonal at the 500mb level as the disturbance
that brings rain to the region Friday night moves off toward the
east. The forecast challenge for Saturday is how quickly the storms
exit the forecast area as the deterministic models are struggling to
come into better agreement. The trend has been just a bit slower, as
evident from comparing previous runs with the 12Z runs. The NAM has
been the quickest and conversely, the GFS messy and the slowest. The
09Z SREF seems to be the better compromise and have leaned toward it
to show a general partial clearing from west to east throughout the
day.
Through the remainder of the weekend, much of Saturday night should
be dry before the atmosphere recharges ahead of the next system.
We`ll remain under southerly flow with high pressure centered over
the Atlantic, allowing for GoMex moisture to pool into the region.
Under this warm , moist air advection regime, Sunday`s forecast is
also a bit tricky as we could see some sporadic storms firing up,
especially with diurnal heating throughout the day. There is no
obvious signal for which portions of the forecast area will see
better rain chances than others given this type of setup so have
broad brushed low-end chance PoPs throughout. After the sun sets on
Sunday, should see a wane in storm coverage with the loss of the
aforementioned heating. Something to watch for, however, is that the
12Z NAM is hinting at a mesoscale convective system to build across
eastern KS/central MO and race off into the Great Lakes region late
Saturday night through Sunday. This is in response to a surface low
that develops just behind it. The NAM is depicting the eastern
portion of this system to break off and jet across central KY before
dying out as it loses its forcing mechanism. We`ll have to see how
this evolves as we approach that time frame.
As if the models haven`t been struggling enough, true temporal
divergence becomes evident early next week as an amplified pattern
sets up: troughing across the Plains and ridging over the East
Coast. The GFS has been consistently fast with the ECMWF much
slower. Have attempted to blend and compromise between the two,
coming to the uncertain conclusion that Tuesday looks to be the best
chance for active weather across the area. One thing the models do
agree on is the pattern change coming by the middle to end of next
week.
Given the unsettled nature of the upcoming pattern, temperature
forecasts will be difficult to nail down with certainty, with clouds
potentially wrecking havoc on the highs/lows. However, taking into
consideration the type of airmasses we`ll be under, along with climo
for this time of year, the warmest days of the long-term period will
be Sunday and Monday, with Saturday and Tuesday being slightly
cooler, and Wednesday onward dropping well below normal. This
forecast update will show highs in the upper 70s on Saturday as
clouds and precip exit; highs in the lower 80s Sunday - Monday under
southerly flow/WAA; Tuesday in the mid to upper 70s with stormy
conditions; and 60s Wednesday - Thursday. Look for lows to respond
accordingly with 60s Saturday night - Monday night and flirting with
the 50 degree mark Tuesday night - Wednesday night.
&&
.AVIATION (12Z TAF Update)...
Issued at 635 AM EDT Fri May 9 2014
A surface cold front will push eastward toward the region today.
Abundant high cloud cover will continue to advect eastward across
the terminals today producing high ceilings. Scattered showers over
western KY will continue to move east and may affect KSDF and KBWG
by mid to late morning. Stronger aviation concern that will emerge
this morning will be the increase in southwesterly winds at the
terminals. We expect winds to pick up around 09/14Z or so with
sustained winds of 12-16kts and gusts up to 20kts. Scattered
convection is expected to further develop this afternoon and evening
as the frontal boundary gets closer to the region. VFR conditions
are expected to prevail at the terminals, but some temporary MVFR
cigs within passing convection will be possible. Overall convective
coverage should diminish toward sunset, but a secondary line of
convection may develop out to the west and affect the terminals
after 10/02Z.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........TWF/MJ
Short Term.....MJ
Long Term......BJS
Aviation.......MJ
AREA FORECAST DISCUSSION
NWS JACKSON KY
754 AM EDT FRI MAY 9 2014
.UPDATE...
ISSUED AT 709 AM EDT FRI MAY 9 2014
UPDATED GRIDS FOR LATEST TRENDS...MAINLY IN RADAR RETURNS. SEEING
AN OCCASIONAL 35 TO 45 DBZ ECHO WITHIN A BAND MOVING UP FROM THE
SOUTHWEST. AT THAT STRENGTH EXPECT THERE SHOULD BE SOME LIGHT
RAINFALL REACHING THE GROUND. MORE ISOLD CELLS ARE APPEARING FURTHER
SOUTHWEST BUT MOVING NORTHEASTWARD AT A QUICK PACE. HRRR HAS A GOOD
HANDLE ON THIS. BOTTOM LINE...BROUGHT POPS IN A BIT QUICKER THROUGH
THE DAY. OTHERWISE, NO MAJOR CHANGES TO THE FORECAST ATTM.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 339 AM EDT FRI MAY 9 2014
FORECASTING THUNDER REMAINS A CHALLENGE AS THE LATEST RUN OF THE RAP
HAS INCREASED SFC DEW POINTS CONSIDERABLY FROM JUST A FEW HOURS
EARLIER FOR THIS AFTERNOON. STILL CAN NOT HELP BUT TO BELIEVE MODELS
ARE OVER DOING MOISTURE BASED ON RECENT HISTORY IF NOTHING ELSE. EVEN
THE NAM...WITH ITS TYPICALLY OVERDONE SFC DEW POINTS IS ADVERTISING
NOTHING MORE THAN SCATTERED THUNDER. IN ADDITION...LATEST RUN OF THE
HRRR SUGGEST THE STRONGEST CONVECTION WILL REMAIN SOUTH OF OUR AREA
IN TN. HAVE DECIDED TO GO WITH JUST A CHANCE OF THUNDER FOR TODAY.
WITH RELATIVELY DRIER BOUNDARY LAYER STILL EXPECT ANY SHOWERS AND/OR
THUNDERSTORMS THAT DEVELOP WILL TEND TO BE HIGH BASED AND PRODUCE
GUSTY WINDS.
THE THREAT OF UNSETTLED WEATHER CONTINUES THROUGH THE REMAINDER OF
THE SHORT TERM. HAVE NOTICED WITH THE LATEST MODEL RUNS THAT THE
FRONTAL BOUNDARY BECOMES MORE DIFFUSE WITH TIME...EVEN TO THE POINT
OF POSSIBLY WASHING OUT SOMEWHERE OVER THE REGION BY SATURDAY. WITH
REMNANTS OF THE BOUNDARY IN THE AREA...AND BETTER SURFACE MOISTURE TO
WORK WITH TONIGHT AND SATURDAY WILL GENERALLY MAINTAIN INHERITED POPS
THROUGH THE PERIOD. OTHERWISE...NUDGED TEMPS TOWARDS LATEST BLEND OF
MODEL/GUIDANCE.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 339 AM EDT FRI MAY 9 2014
A VERY UNCERTAIN LONG TERM PERIOD SETTING UP THROUGH NEXT WEEK.
STRONG MID TO UPPER LEVEL RIDGING WILL REMAIN ANCHORED OVER THE
EASTERN US THROUGH TUESDAY. HOWEVER...MODELS ARE SHOWING SOME SUBTLE
WAVES PUSHING THROUGH THE RIDGE AXIS AT TIMES. FEEL THESE WAVES MAY
BE OVER PRONOUNCED IN THE MODELS GIVEN THE IMPRESSIVE HEIGHTS OVER
THE AREA. HOWEVER...GIVEN THE WARMTH...AND SLIGHTLY BETTER SFC
MOISTURE INTO EARLY THIS WEEK...IT IS POSSIBLE WE COULD SEE A SHOWER
OR THUNDERSTORM EACH AFTERNOON OR EARLY EVENING. CERTAINLY DOESN`T
LOOK LIKE A WASH OUT BY ANY MEANS...BUT THE SMALL THREAT IS THERE.
IT APPEARS THE BETTER CHANCES FOR SHOWERS AND STORMS WILL COME
MIDWEEK AS A STRONG COLD FRONT MARCHES EAST ACROSS THE AREA. MODELS
REMAIN IN STARK CONTRAST WITH REGARDS TO TIMING THIS FEATURE ACROSS
THE AREA...SO HAVE GONE WITH A PERIOD OF HIGHER POPS FROM TUESDAY
NIGHT THROUGH WEDNESDAY EVENING. MOST LIKELY THE PERIOD OF UNSETTLED
WEATHER WILL BE MUCH MORE NARROW THAN THIS WINDOW. IT DOES APPEAR
THE WEATHER SHOULD TURN COOL AND DRIER BY THURSDAY...BUT AN UPPER
LEVEL TROUGH MAY BRING SOME UNSETTLED WEATHER BACK TO THE AREA BY
WEEKS END. GIVEN THE UNCERTAINTY WITH PRECIPITATION CHANCES THIS
WEEK...HAVE GONE WITH ASSUMPTION...MOST DAYS WILL FEATURE DRY
WEATHER AND THUS...WARMER TEMPERATURES...AT LEAST THROUGH TUESDAY.
BY WEDNESDAY...TEMPERATURES WILL START TO TAKE A STEP
DOWNWARDS...AND CERTAINLY BY WEDNESDAY WITH HIGHS LIKELY BACK INTO
THE 60S.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 754 AM EDT FRI MAY 9 2014
IN GENERAL EXPECTING VFR CONDITIONS THROUGH THE ENTIRE FORECAST
PERIOD.
RADAR SHOWING SOME ISOLATED SHOWERS ALREADY ENTERING THE AREA THIS
MORNING. MORE SCATTERED SHOWERS TO THE SOUTHWEST...AND A LARGER BAND
OF RAIN WHICH WILL BE MOVING INTO THE AREA AS THE DAY PROGRESSES.
FORECAST SOUNDINGS NOT THE MOST FAVORABLE FOR THUNDER TODAY WITH
RELATIVELY DRY LOWER LEVELS AND MOSTLY CLOUDY SKIES HELPING TO KEEP
TEMPERATURES...SURFACE BASED INSTABILITY DOWN A BIT. BUT CAN NOT
RULE OUT THUNDER ALTOGETHER. FOR NOW PLAYED DOWN THUNDER IN THE TAFS
UNTIL TONIGHT WHERE SOUNDINGS LOOK MORE UNSTABLE GOING INTO SATURDAY
MORNING DUE TO A SURFACE FRONTAL BOUNDARY MAKING AN HONEST PUSH
TOWARDS OUR AREA AND AS MOISTURE INCREASES AT THE SURFACE AHEAD OF
THIS SYSTEM. FOR NOW IT APPEARS THIS FRONT WILL STALL AND WASH OUT
SOMETIME SATURDAY.
WINDS WILL GENERALLY INCREASE FROM THE SOUTH...SOUTHWEST AT 10-15 KTS
THROUGH THE DAY WITH AN OCCASIONAL HIGHER GUST. HOWEVER...WITH
RELATIVELY DRIER LOW LEVELS WINDS COULD BE VARIABLE AND GUSTY AROUND
ANY SHOWERS AND THUNDERSTORMS THAT DO DEVELOP. GUSTY WIND THREAT
ASSOCIATED WITH SHOWERS AND ANY THUNDERSOTRMS WILL ABATE AS RAINFALL
MOISTENS UP THE LOWER LEVELS.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
UPDATE...RAY
SHORT TERM...RAY
LONG TERM...KAS
AVIATION...RAY
AREA FORECAST DISCUSSION
NWS JACKSON KY
709 AM EDT FRI MAY 9 2014
.UPDATE...
ISSUED AT 709 AM EDT FRI MAY 9 2014
UPDATED GRIDS FOR LATEST TRENDS...MAINLY IN RADAR RETURNS. SEEING
AN OCCASIONAL 35 TO 45 DBZ ECHO WITHIN A BAND MOVING UP FROM THE
SOUTHWEST. AT THAT STRENGTH EXPECT THERE SHOULD BE SOME LIGHT
RAINFALL REACHING THE GROUND. MORE ISOLD CELLS ARE APPEARING FURTHER
SOUTHWEST BUT MOVING NORTHEASTWARD AT A QUICK PACE. HRRR HAS A GOOD
HANDLE ON THIS. BOTTOM LINE...BROUGHT POPS IN A BIT QUICKER THROUGH
THE DAY. OTHERWISE, NO MAJOR CHANGES TO THE FORECAST ATTM.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 339 AM EDT FRI MAY 9 2014
FORECASTING THUNDER REMAINS A CHALLENGE AS THE LATEST RUN OF THE RAP
HAS INCREASED SFC DEW POINTS CONSIDERABLY FROM JUST A FEW HOURS
EARLIER FOR THIS AFTERNOON. STILL CAN NOT HELP BUT TO BELIEVE MODELS
ARE OVER DOING MOISTURE BASED ON RECENT HISTORY IF NOTHING ELSE. EVEN
THE NAM...WITH ITS TYPICALLY OVERDONE SFC DEW POINTS IS ADVERTISING
NOTHING MORE THAN SCATTERED THUNDER. IN ADDITION...LATEST RUN OF THE
HRRR SUGGEST THE STRONGEST CONVECTION WILL REMAIN SOUTH OF OUR AREA
IN TN. HAVE DECIDED TO GO WITH JUST A CHANCE OF THUNDER FOR TODAY.
WITH RELATIVELY DRIER BOUNDARY LAYER STILL EXPECT ANY SHOWERS AND/OR
THUNDERSTORMS THAT DEVELOP WILL TEND TO BE HIGH BASED AND PRODUCE
GUSTY WINDS.
THE THREAT OF UNSETTLED WEATHER CONTINUES THROUGH THE REMAINDER OF
THE SHORT TERM. HAVE NOTICED WITH THE LATEST MODEL RUNS THAT THE
FRONTAL BOUNDARY BECOMES MORE DIFFUSE WITH TIME...EVEN TO THE POINT
OF POSSIBLY WASHING OUT SOMEWHERE OVER THE REGION BY SATURDAY. WITH
REMNANTS OF THE BOUNDARY IN THE AREA...AND BETTER SURFACE MOISTURE TO
WORK WITH TONIGHT AND SATURDAY WILL GENERALLY MAINTAIN INHERITED POPS
THROUGH THE PERIOD. OTHERWISE...NUDGED TEMPS TOWARDS LATEST BLEND OF
MODEL/GUIDANCE.
.LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY)
ISSUED AT 339 AM EDT FRI MAY 9 2014
A VERY UNCERTAIN LONG TERM PERIOD SETTING UP THROUGH NEXT WEEK.
STRONG MID TO UPPER LEVEL RIDGING WILL REMAIN ANCHORED OVER THE
EASTERN US THROUGH TUESDAY. HOWEVER...MODELS ARE SHOWING SOME SUBTLE
WAVES PUSHING THROUGH THE RIDGE AXIS AT TIMES. FEEL THESE WAVES MAY
BE OVER PRONOUNCED IN THE MODELS GIVEN THE IMPRESSIVE HEIGHTS OVER
THE AREA. HOWEVER...GIVEN THE WARMTH...AND SLIGHTLY BETTER SFC
MOISTURE INTO EARLY THIS WEEK...IT IS POSSIBLE WE COULD SEE A SHOWER
OR THUNDERSTORM EACH AFTERNOON OR EARLY EVENING. CERTAINLY DOESN`T
LOOK LIKE A WASH OUT BY ANY MEANS...BUT THE SMALL THREAT IS THERE.
IT APPEARS THE BETTER CHANCES FOR SHOWERS AND STORMS WILL COME
MIDWEEK AS A STRONG COLD FRONT MARCHES EAST ACROSS THE AREA. MODELS
REMAIN IN STARK CONTRAST WITH REGARDS TO TIMING THIS FEATURE ACROSS
THE AREA...SO HAVE GONE WITH A PERIOD OF HIGHER POPS FROM TUESDAY
NIGHT THROUGH WEDNESDAY EVENING. MOST LIKELY THE PERIOD OF UNSETTLED
WEATHER WILL BE MUCH MORE NARROW THAN THIS WINDOW. IT DOES APPEAR
THE WEATHER SHOULD TURN COOL AND DRIER BY THURSDAY...BUT AN UPPER
LEVEL TROUGH MAY BRING SOME UNSETTLED WEATHER BACK TO THE AREA BY
WEEKS END. GIVEN THE UNCERTAINTY WITH PRECIPITATION CHANCES THIS
WEEK...HAVE GONE WITH ASSUMPTION...MOST DAYS WILL FEATURE DRY
WEATHER AND THUS...WARMER TEMPERATURES...AT LEAST THROUGH TUESDAY.
BY WEDNESDAY...TEMPERATURES WILL START TO TAKE A STEP
DOWNWARDS...AND CERTAINLY BY WEDNESDAY WITH HIGHS LIKELY BACK INTO
THE 60S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 205 AM EDT FRI MAY 9 2014
LOOKING AT VFR CONDITIONS THROUGH THE ENTIRE FORECAST PERIOD. MAIN
CHALLENGE TO THE AVIATION FORECAST WILL BE THE POTENTIAL FOR
THUNDERSTORMS LATER TODAY. THINGS DO NOT LOOK REAL IMPRESSIVE BASED
ON LATEST FORECAST SOUNDINGS. BELIEVE MODELS...NAM/GFS ARE OVERDOING
SFC MOISTURE AGAIN AND CONSEQUENTLY SFC BASED INSTABILITY. SOUNDINGS
ALSO HAVE THE FAMILIAR INVERTED V PROFILE TYPICALLY SEEN IN THE
WESTERN CONUS. THOUGHTS ARE THAT WE MAY CUT BACK ON PROBABILITY OF
THUNDER...FROM LIKELY TO CHANCE. HOWEVER...WITH DIRER LOWER LEVELS
THIS ALSO MEANS THAT ANY SHOWERS THAT DEVELOP WILL TEND TO BE HIGH
BASED AND PRODUCE GUSTY WINDS DUE TO THE ADDITIVE MOMENTUM OF
EVAPORATIVE COOLING OF RAINFALL. LIGHT AND VARIABLE WILL INCREASE
FROM THE SOUTH...SOUTHWEST AT 10 TO 15 KTS BY MIDDAY FRIDAY. A FEW
GUSTS TO 20 KTS WILL BE POSSIBLE LATE IN THE DAY FRIDAY. AGAIN...
WINDS COULD BE QUITE VARIABLE AND GUSTY AROUND ANY SHOWERS AND
THUNDERSTORMS THAT MAY DEVELOP.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
UPDATE...RAY
SHORT TERM...RAY
LONG TERM...KAS
AVIATION...RAY
AREA FORECAST DISCUSSION
NWS JACKSON KY
205 AM EDT FRI MAY 9 2014
.UPDATE...
ISSUED AT 205 AM EDT FRI MAY 9 2014
GRIDS AND FORECAST ARE IN FINE SHAPE EARLY THIS MORNING. ONLY MADE
SOME MINOR TWEAKS TO MATCH UP WITH HOURLY TRENDS. LOOKING OVER LATEST
FORECAST SOUNDINGS FOR THIS AFTERNOON...AND THINGS DO NOT LOOK REAL
IMPRESSIVE. BELIEVE MODELS...NAM/GFS ARE OVERDOING SFC MOISTURE AGAIN
AND CONSEQUENTLY SFC BASED INSTABILITY. INTERESTINGLY...GFS MODEL
GUIDANCE IS ADVERTISING ONLY A 20-30 PERCENT CHANGE OF THUNDER. NAM
MET MOS IS HIGHER...BUT ONLY DUE TO THE TYPICALLY HIGHER BIAS IN SFC
DEW POINTS AND IS STILL ONLY SHOWING A 40 PERCENT CHANCE OF THUNDER.
APPEARS THE DRIER RAP MAY HAVE A SLIGHTLY BETTER HANDLE ON THINGS.
IN ADDITION...SOUNDINGS HAVE THAT FAMILIAR INVERTED V PROFILE
TYPICALLY SEEN IN THE WESTERN CONUS. MAY DECIDE TO CUT BACK ON
PROBABILITY OF THUNDER WITH NEXT UPDATE...FROM LIKELY TO CHANCE.
HOWEVER...WITH DRIER LOWER LEVELS THIS ALSO MEANS THAT ANY SHOWERS
THAT DEVELOP WILL TEND TO BE HIGH BASED AND PRODUCE GUSTY WINDS DUE
TO THE ADDITIVE MOMENTUM OF EVAPORATIVE COOLING. BUT WILL
EVALUATE/COLLABORATE WITH NEIGHBORS BEFORE MAKING ANY FINAL
DECISIONS.
UPDATE ISSUED AT 1055 PM EDT THU MAY 8 2014
DID A QUICK UPDATE TO FINE TUNE THE SKY COVER WEST TO EAST OVERNIGHT.
ALSO TWEAKED THE T/TD GRIDS THROUGH THE EARLY OVERNIGHT BASED ON THE
LATEST OBS AND TRENDS. UPDATES HAVE BEEN SENT TO THE NDFD AND WEB
SERVERS.
UPDATE ISSUED AT 730 PM EDT THU MAY 8 2014
23Z SFC ANALYSIS SHOWS WEAK HIGH PRESSURE HOLDING ON OVER THE
SOUTHEAST PART OF THE NATION WHILE EAST KENTUCKY REMAINS IN THE BROAD
WARM SECTOR OF A LARGE HIGH PLAINS LOW. WARM MID LEVEL TEMPERATURES
CONTINUE TO CAP THE AREA PREVENTING ANY CONVECTION AND LIMITING THE
LOWER CLOUDS TODAY. THIS HELPED SEND TEMPERATURES INTO RECORD AND
NEAR RECORD TERRITORY AGAIN THIS AFTERNOON. SOME HIGH CLOUDS ARE NOW
STARTING TO THICKEN UP OVER THE REGION IN RESPONSE TO THE PLAINS
SYSTEM/S COLD FRONT MOVING EAST. DO NOT EXPECT THESE CLOUDS TO
COMPLETELY COVER THE AREA BEFORE MUCH LATER TONIGHT...BUT THEY WILL
STILL LIKELY IMPACT THE NATURE OF THE PERSISTENT RIDGE AND VALLEY
TEMPERATURE SPLITS THAT WE HAVE BEEN SEEING THE PAST SEVERAL NIGHTS.
WILL STILL FORECAST ONE...PARTICULARLY IN THE EAST...BUT TEMPER IT
FOR MOST OF THE AREA AND FORECAST THE BEST AND FASTEST TEMPERATURE
DECLINES EARLIER IN THE NIGHT. HAVE UPDATED THE GRIDS WITH THESE
THOUGHTS IN MIND...AS WELL AS INCORPORATING THE LATEST OBS AND TRENDS
FOR THE NEAR TERM. THESE HAVE BEEN SENT TO THE NDFD AND WEB SERVERS.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT)
ISSUED AT 250 PM EDT THU MAY 8 2014
THE MODELS ACTUALLY HAVE QUITE A BIT OF DIFFERENCE IN THE TIMING OF
THIS NEXT SYSTEM APPROACHING THE AREA TOMORROW. BY 8 PM ON FRIDAY...A
COLD FRONT WILL EXTEND ACROSS WESTERN MICHIGAN TO SOUTHEASTERN
MISSOURI AND THE INTO THE TEXAS MIDLANDS. THERE WILL BE SHOWERS AND
THUNDERSTORMS FIRING UP AHEAD OF THIS SYSTEM ON FRIDAY. THIS IS WHERE
THE MODELS DIVERGE AS TO THE EXTENT AND TIMING OF THE PREFRONTAL
STORMS IN THE WARM SECTOR. THE TIME OF ARRIVAL FOR THE LEADING EDGE IN
THE MODELS VARY FROM 5 PM FRIDAY TO 10 PM ON FRIDAY. THE MODEL
CONSENSUS WOULD FAVOR THE LATER ARRIVAL TIME. THE BEST CHANCE FOR
WIDESPREAD SHOWERS AND THUNDERSTORMS WILL BE LATE FRIDAY NIGHT AND
INTO SATURDAY. THE FRONT SHOULD BE MOVING INTO EASTERN KENTUCKY ON
SATURDAY MORNING. THE THREAT OF ANY SEVERE THUNDERSTORMS WITH THE
SYSTEM IS VERY LOW AND ONLY GARDEN VARIETY STORMS ARE EXPECTED WITH
THIS SYSTEM.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 334 PM EDT THU MAY 8 2014
THE MODELS WERE NOT IN THE BEST OF AGREEMENT THIS GO ROUND...SO THE
EXTENDED PORTION OF THE FORECAST MADE WITH LOW CONFIDENCE. THE
OVERALL PATTERN SUGGESTS A THAT INITIALLY A FAIRLY WELL DEFINED COLD
FRONT WILL MOVE SLOWLY ACROSS THE AREA SATURDAY AND SATURDAY NIGHT.
WITH AMPLE MOISTURE AND INSTABILITY IN PLACE...THE START OF THE
PERIOD DOES LOOK FAIRLY GOOD IN TERMS OF THE VARIOUS MODEL SOLUTIONS
AND THEIR AGREEMENT THERE. THEREFORE...DECIDED TO CONTINUE WITH THE
LIKELY PRECIPITATION PROBABILITIES TO END THE WEEKEND ACROSS THE
AREA. AFTER THAT...HOWEVER...THE MODELS GO QUITE A BIT OUT OF
AGREEMENT. THE GFS IS MUCH FASTER THAN THE ECMWF WITH THE PROGRESSION
OF A LARGE SCALE UPPER TROUGH THROUGHOUT THE WORK WEEK...AND A SERIES
OF FRONTAL BOUNDARIES THAT ARE PROGGED TO AFFECT THE AREA. WITH THE
AMOUNT OF UNCERTAINTY WE ARE SEEING...IT SEEMED PLAUSIBLE TO ADJUST
THE LATEST MODEL DATA INGEST VERY LITTLE AND KEEP IN LINE WITH OUR
NEIGHBORS. IT LOOKS LIKE ISENTROPIC LIFT ASSOCIATED WITH A WARM FRONT
WILL BE THE CULPRIT FOR PRECIPITATION THROUGHOUT THE PERIOD WHEN A
COLD FRONT LOOMS TO OUR WEST IN THE WARM SECTOR OF AN APPROACHING
AREA OF LOW PRESSURE. AT THIS TIME...THE FORECAST WILL CALL FOR
PERIODS OF SHOWERS AND THUNDERSTORMS THROUGHOUT THE WEEK...WITH SOME
BREAKS FROM THE PRECIP HERE AND THERE AS THE WARM MIGRATES NORTH OF
THE OHIO RIVER. TEMPERATURES DURING THE PERIOD SHOULD BE QUITE
WARM...WITH DAILY HIGHS IN THE 70S AND 80S THROUGH TUESDAY. COOLER
TEMPERATURES COULD BE ON TAP TO END THE WEEK...IF A SECOND AREA OF
LOW PRESSURE IN FACT DOES IMPACT THE AREA. TEMPERATURES NEXT
WEDNESDAY AND THURSDAY MAY ONLY MAKE IT INTO THE 60S ACROSS THE BOARD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 205 AM EDT FRI MAY 9 2014
LOOKING AT VFR CONDITIONS THROUGH THE ENTIRE FORECAST PERIOD. MAIN
CHALLENGE TO THE AVIATION FORECAST WILL BE THE POTENTIAL FOR
THUNDERSTORMS LATER TODAY. THINGS DO NOT LOOK REAL IMPRESSIVE BASED
ON LATEST FORECAST SOUNDINGS. BELIEVE MODELS...NAM/GFS ARE OVERDOING
SFC MOISTURE AGAIN AND CONSEQUENTLY SFC BASED INSTABILITY. SOUNDINGS
ALSO HAVE THE FAMILIAR INVERTED V PROFILE TYPICALLY SEEN IN THE
WESTERN CONUS. THOUGHTS ARE THAT WE MAY CUT BACK ON PROBABILITY OF
THUNDER...FROM LIKELY TO CHANCE. HOWEVER...WITH DIRER LOWER LEVELS
THIS ALSO MEANS THAT ANY SHOWERS THAT DEVELOP WILL TEND TO BE HIGH
BASED AND PRODUCE GUSTY WINDS DUE TO THE ADDITIVE MOMENTUM OF
EVAPORATIVE COOLING OF RAINFALL. LIGHT AND VARIABLE WILL INCREASE
FROM THE SOUTH...SOUTHWEST AT 10 TO 15 KTS BY MIDDAY FRIDAY. A FEW
GUSTS TO 20 KTS WILL BE POSSIBLE LATE IN THE DAY FRIDAY. AGAIN...
WINDS COULD BE QUITE VARIABLE AND GUSTY AROUND ANY SHOWERS AND
THUNDERSTORMS THAT MAY DEVELOP.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
UPDATE...RAY
SHORT TERM...JJ
LONG TERM...AR
AVIATION...RAY
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1122 PM CDT Thu May 8 2014
.UPDATE...
Issued at 1122 PM CDT THU MAY 8 2014
Update for 6z aviation only.
UPDATE Issued at 845 PM CDT THU MAY 8 2014
A north to south oriented line of thunderstorms with trailing
stratiform rain is approaching the Mississippi River and will
continue to move north northeast into southern Illinois mainly to
the west of I-57 through the remainder of the evening. It looks
like western portions of southeast Missouri will be drying out
pretty soon, and they may have a few hours before the next round
arrives midnight or a bit later.
LAPS soundings indicate a weakening cap and the RAP has LI`s of
-2 to -3 over southern Illinois. See no reason why they will not
continue through much of southern Illinois with modest intensity
this evening. Not sure just how far east they will get, but the
RAP tries hard to confine the precipitation to Missouri and
Illinois through midnight. Of course, as the upper trough pushes
closer to the area overnight, another round of widespread showers
and thunderstorms is expected to overspread most of the area by
daybreak Friday morning.
Tried to account for the aforementioned trends in the hourly
pop/wx grids, but made few other changes with this update.
The Lake Wind Advisory died a natural death at 01Z.
UPDATE Issued at 610 PM CDT THU MAY 8 2014
UPDATE FOR AVIATION ONLY.
&&
.SHORT TERM...(Tonight through Saturday night)
Issued at 304 PM CDT THU MAY 8 2014
Focus in the short term continues to be on convective chances.
Band of convection central/sw MO into west AR will track slowly
east late this afternoon and evening. Will have best chance PoPs
west 1/2 before midnight shifting slowly east overnight. Really
not all that concerned about severe wx over our SEMO counties
at this time given marginal lapse rates modest instability.
Convective chances will shift east Friday morning. It may linger
from SW IN into the Pennyrile through early afternoon, where temps
may be held down a couple of degrees. Otherwise, the atmosphere
should have some time to recover heading west, ahead of an
approaching, stalling front. Convection should take shape in this
area and eventually focus SRN IL into SE MO late in the day in
some form or fashion then head east through the evening. Mid and
upper level winds are relatively impressive, not so much blyr-
700mb. Storms with decent mid level rotation, with steepening low
level lapse rates may yield wind and hailers, best chances
west/southwest part of the CWFA. Chances should diminish from west
to east after midnight Friday night. May see a lull Saturday, then
another chance moving in from the west overnight Saturday night,
potentially an MCS. Slightly better chances north than south.
.LONG TERM...(Sunday through Thursday)
Issued at 304 PM CDT THU MAY 8 2014
The main weather story during the long term will be a strong cold
front that will sweep across our region early next week. This front
will be accompanied by a period of rain and thunderstorms. The front
will bring a noticeable cooling of temperatures from above normal to
below normal.
As far as the daily details...
On Sunday...a reservoir of warm...moist and very unstable air will
cover a large part of the central states including our region. It is
likely that one or more convective systems will develop over the
Plains and then propagate eastward through this unstable air
mass...fed by a moderately strong low level jet. Since there is
little skill at forecasting these systems in the long range
period...the forecast will include a generic chance pop. High temps
will remain quite warm...basically in line with gfs/ecmwf mos.
On Monday...the high amplitude 500 mb trough and associated cold
front will draw closer. The genesis region of convective systems
will remain to our west. Will continue with a warm and humid
forecast along with chance pops.
There remains unusually wide divergence among the models concerning
the timing of the frontal system Monday night through Tuesday night.
Both the gfs and ecmwf have trended slower compared to this time
Wednesday. The 12z gfs takes the front across our region on Monday
night...while the ecmwf has it coming through Tuesday night. The
highest pops will be on Tuesday...mainly in the likely category
across our region. Will introduce chance pops for Wednesday based on
the slower timing of the system. However...the bulk of the precip
should be over by then.
The model 850 temps have trended cooler for Wednesday into Thursday
by several degrees. Based on model 850 mb temps from plus 1 to plus
4...highs will only be in the 60s even with plenty of sun. Forecast
temps will be trended lower for Wed into Thurs.
&&
.AVIATION...
Issued at 1122 PM CDT THU MAY 8 2014
Kcgi is expected to break out of the precip between 6z and 9z.
After that rain will start to move in again. However raised cigs
prevailing and tempo in light of the vfr cigs in tsra earlier.
Slowly bring them into MVFR territory between 9z and 18z. Then
only a prob group after that. Also maintained LLWS overnight as
fcst sounding indicate 40kt at 2k feet.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
UPDATE...KH
AVIATION...KH
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
116 PM CDT FRI MAY 9 2014
.AVIATION...
AFTER A MORNING OF IFR CEILINGS AND VCTS ACROSS SEVERAL TERMINALS...
CEILING`S HAVE LIFTED AND OUR SCATTERED OUT ACROSS SOME TERMINALS
EARLY THIS AFTERNOON. STILL DEALING WITH MVFR CONDITIONS HOWEVER
AT THE ELD/LFK AND SHV TERMINALS. THIS SHOULD BE TEMPORARY WITH
CEILING`S LIKELY CLIMBING ABOVE 3KFT OVER THE NEXT HOUR OR SO.
CONVECTION FOR THE MOST PART HAS MOVED SOUTH AND EAST OF OUR
TERMINALS BUT LEFT MENTION OF VCTS AT THE LFK/MLU TERMINALS
THROUGH THE AFTERNOON. HRRR SHOWING REDEVELOPMENT ACROSS THE
REGION LATER THIS AFTERNOON...AND FOR THAT REASON...HAVE
REINTRODUCED VCTS AT SEVERAL TERMINAL LOCATIONS THROUGH THE
EVENING.
BY LATE EVENING/OVERNIGHT...MOS CEILING CATEGORIES SUPPORT A
RETURN OF MVFR/IFR CEILINGS AREAWIDE WITH SOME 3-5SM VISIBILITIES.
KEPT THIS RUNNING THROUGH AT LEAST MID MORNING ON SATURDAY WITH
IFR CEILINGS LIKELY NOT LIFTING UNTIL AFTER 15Z ON SATURDAY.
13
&&
.PREV DISCUSSION... /ISSUED 1126 AM CDT FRI MAY 9 2014/
DISCUSSION...
ONGOING CONVECTION MAINLY SOUTH OF I-20 LATE THIS MORNING WITH
SOME IMPRESSIVE RAINFALL RATES/TOTALS ACROSS PARTS OF DEEP E
TX...PROMPTING A FLASH FLOOD WARNING FOR THIS AREA. ELSEWHERE
ALONG AND SOUTH OF I-20...JUST SPOTTY SHWRS AND A FEW TSTMS NOTED
ON RADAR WITH CLOUDS TRYING TO ERODE OVER PORTIONS OF NE TX WITH A
COLD FRONTAL BNDRY JUST TO OUR WEST. THIS BNDRY IS EXPECTED TO
WEAKEN AND TRACK JUST NORTH OF OUR REGION THIS AFTERNOON WITH A
FEW UPPER LEVEL DISTURBANCES TRANSITIONING EWRD WITH THE FRONT.
THEREFORE...ADDITIONAL CONVECTION IS EXPECTED TO DEVELOP LATER
THIS AFTERNOON WITH SOME STRONG TO POSSIBLY ISOLD SEVERE TSTMS.
THE THREATS WITH ANY OF THESE TSTMS WILL BE LIMITED TO DAMAGING
WINDS AND HAIL AS INDICATED BY THE DAY 1 SPC CONVECTIVE OUTLOOK.
AS FAR AS CHANGES TO THE FORECAST...DID MAKE UPWARD ADJUSTMENTS TO
POPS MAINLY ALONG AND SOUTH OF I-20 WHERE MORNING CONVECTION IS
CONCENTRATED. ALSO LOWERED FORECAST HIGHS JUST A BIT CONSIDERING
THE ABUNDANT CLOUD COVER AND CONVECTION...ALTHOUGH WOULD NOT BE
SURPRISED TO SEE A FEW AREAS SQUEAK OUT MID OR EVEN UPPER 80S
WHERE CLOUDS BREAK EARLIER AND CONVECTION IS KEPT AT BAY. NEW QPF
NUMBERS HAVE ALSO BEEN LOADED INTO THE GRIDS. UPDATED PRODUCTS
HAVE ALREADY BEEN SENT. /19/
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 68 87 70 86 71 / 20 20 20 20 20
MLU 67 87 69 86 69 / 30 20 20 20 20
DEQ 64 86 67 84 70 / 20 20 20 20 20
TXK 67 86 68 85 68 / 20 20 20 20 20
ELD 66 86 68 85 68 / 30 20 20 20 20
TYR 68 87 70 86 71 / 20 20 10 20 20
GGG 67 88 69 86 71 / 20 20 10 20 20
LFK 69 88 71 87 72 / 20 20 10 20 20
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
13
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1153 PM CDT THU MAY 8 2014
.AVIATION...
A LINE OF STRONG CONVECTION WILL CONTINUE TO MOVE EAST ACROSS
PORTIONS THE FORECAST AREA EARLY THIS MORNING. EXPECT MODERATE TO
ISOLATED SEVERE TURBULENCE WITH THIS ACTIVITY AS WELL AS PERIODS
OF IFR CIGS AND VSBYS DUE TO HEAVY RAINFALL. FOLLOWING THE
LINE...CIGS MAY CLEAR BRIEFLY ACROSS EAST TEXAS INTO SOUTHEAST
OKLAHOMA AND SOUTHWEST ARKANSAS. HOWEVER...AFTER 09Z...EXPECT IFR
FLIGHT CONDITIONS TO RETURN IN SOME LOCATIONS DUE TO FOG AND/OR
LOW CIGS. ACROSS LOUISIANA...CIGS WILL REMAIN MOSTLY MVFR WITH
OCCASIONAL VSBYS BETWEEN 2 AND 5 MILES IN RAIN AND FOG. CONDITIONS
WILL IMPROVE BETWEEN 15Z AND 17Z FRIDAY TO VFR MOST LOCATIONS.
EXCEPT FOR WEST TO NORTHWEST WIND GUST TO AROUND 25 KTS IN AND
AROUND CONVECTION...SURFACE WIND TO REMAIN SOUTH 5 TO 10 KTS
TONIGHT. AFTER 14Z FRIDAY...EXPECT SOUTH TO SOUTHWEST WIND 10 TO
15 KTS. /14/
&&
.PREV DISCUSSION... /ISSUED 946 PM CDT THU MAY 8 2014/
DISCUSSION...
MOSAIC RADAR ANALYSIS SHOWING A RATHER LARGE LINE OF CONVECTION
EXTENDING FROM SOUTH CENTRAL ARKANSAS THROUGH EXTREME NORTHWEST
LOUISIANA AND NORTHEAST TEXAS. THIS ACTIVITY DEVELOPING WELL AHEAD
OF THE SHORTWAVE TROUGH WHICH IS CURRENT ACROSS THE TX/OK PNHDL
INTO THE SOUTHERN AND CENTRAL PLAINS. HRRR HAS A GOOD HANDLE ON
THIS CONVECTION CONTINUING TO PUSH SOUTH AND EAST THROUGH THE
NIGHT WITH RAINFALL RATES NEAR 1.5 INCHES PER HOUR ALONG THE
LEADING EDGE OF THE CONVECTION. HAVE UPDATED THE FORECAST TO GO
WITH CATEGORICAL POPS ACROSS THE NORTHWEST HALF FOR THE REMAINDER
OF THE EVENING AND THEN ACROSS THE EASTERN HALF AFTER MIDNIGHT.
ALSO ADDED THE LOCALLY HEAVY RAINFALL MODIFIER GIVEN THE RAINFALL
RATES AND WHAT HAS ALREADY OCCURRED.
CONCERNING TEMPERATURES...OUR NORTHWEST ZONES ARE ALREADY A DEGREE
OR TWO BELOW FORECAST MINS SO LOWERED MINS BUT THESE TEMPERATURES
MAY RECOVER SLIGHTLY AFTER THE CONVECTION ENDS.
ALSO ADJUSTED SKY/WIND AND DEWPOINT GRIDS BASED ON CURRENT TRENDS.
UPDATE ALREADY SENT...13.
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 68 84 67 87 68 / 80 40 20 20 20
MLU 71 82 66 86 67 / 80 50 30 20 20
DEQ 64 84 61 85 66 / 80 50 20 20 20
TXK 66 83 66 86 67 / 80 50 40 20 20
ELD 66 83 65 86 66 / 80 50 40 20 20
TYR 66 88 66 88 70 / 80 20 20 20 10
GGG 68 87 66 87 70 / 80 30 20 20 10
LFK 71 89 68 88 70 / 80 30 20 20 10
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...NONE.
LA...NONE.
OK...NONE.
TX...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAY ME
1157 PM EDT SAT MAY 10 2014
.SYNOPSIS...
A COLD FRONT WILL STALL BRIEFLY OFFSHORE TONIGHT. HIGH PRESSURE
WILL BUILD IN FOR SUNDAY AND MONDAY. A BACK DOOR COLD FRONT TRACKS
SOUTHWEST ACROSS THE AREA MONDAY NIGHT AND TUESDAY MORNING. HIGH
PRESSURE WILL THEN BUILD IN FROM THE NORTHEAST THROUGH WEDNESDAY.
A SLOW MOVING COLD FRONT WILL MOVE IN FROM THE WEST ON THURSDAY
AND CROSS THE AREA FRIDAY. HIGH PRESSURE WILL ENTER THE REGION
NEXT WEEKEND.
&&
.NEAR TERM /OVERNIGHT/...
MIDNIGHT UPDATE...
HAVE MADE SIGNIFICANT ADJUSTMENTS TO HOURLY TEMPERATURE FORECAST
AS TEMPERATURES REMAIN QUITE WARM EVEN AT THIS LATE HOUR. MOSTLY
UPPER 60S OBSERVED CURRENTLY ALONG WITH A FEW LOW 70S. DEW POINTS
STILL IN THE MID 50S ON THE COASTAL SIDE OF THE MOUNTAINS WHILE
DRIER AIR (DEWPOINTS IN THE 30S) HAS MOVED IN TO THE WEST OF THE
MOUNTAINS. HAVE ADJUSTED THE HOURLY TEMPERATURE TREND TO BE MORE
IN LINE WITH CURRENT OBSERVED TRENDS AND HAVE RAISED LOW
TEMPERATURES FOR MOST AREAS TONIGHT.
830 PM UPDATE...
ELIMINATED ANY RISK OF SHOWERS OVER SOUTHERN MOST AREAS THIS
EVENING AS SHOWERS HAVE ALL MOVED S AND E OF THE AREA. DRIER AIR
MASS WITH MUCH LOWER DEW POINTS CURRENTLY ADVECTING SE ACROSS THE
FORECAST AREA ON AND A DEVELOPING LIGHT WEST SURFACE FLOW. NO
CHANGES TO REST OF FORECAST AT THE MOMENT.
ORIGINAL DISCUSSION...
CLOUDS AND FOG ARE HANGING IN TOUGH OVER EASTERN AREAS LATE THIS
AFTERNOON. OTHERWISE...CLEARING AND SOMEWHAT DRIER AIR CONTINUES
TO MOVE IN FROM THE WEST. THERE IS CONVECTION OVER SOUTHERN NY
WHICH WILL CONTINUE TO MOVE ENE PER LATEST HRRR MODEL RUN.
CONVECTION MAY BRIEFLY REACH SOUTHERNMOST PORTIONS OF THE FORECAST
AREA THIS EVENING...AND HAVE INCLUDED CHANCE POPS FOR THIS REGION
FOR A COUPLE HOURS.
OTHERWISE...THERE APPEARS TO BE SUFFICIENT GRADIENT OVERNIGHT TO
KEEP FOG FROM FORMING.
&&
.SHORT TERM /SUNDAY AND SUNDAY NIGHT/...
OFFSHORE FLOW WILL ALLOW FOR WARM TEMPERATURES ON SUNDAY FOR ALL
AREAS. THIS WILL BRING TEMPERATURES IN THE 70S FOR MANY
SECTIONS...THE FIRST TIME IN QUITE A PERIOD. CYCLONIC FLOW MAY
INDUCE A COUPLE SHOWERS OVER THE FAR NORTHERN MOUNTAINS DURING THE
LATE MORNING AND EARLY AFTERNOON HOURS.
IT WILL BE DRY SUNDAY NIGHT. HOWEVER...A BACK DOOR COLD FRONT MAY
BE APPROACHING THE REGION...RETROGRADING INTO OUR AREA FROM
NORTHEAST TO SOUTHWEST.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
MODELS ARE IN GOOD AGREEMENT THROUGH LATE NEXT WEEK ON LONGWAVE
PATTERN. THE UPPER TROUGH OVER NEW ENGLAND IS LIFTING OUT AS WE
BEGIN THE PERIOD ON MONDAY WITH UPPER RIDGE PROGRESSING EASTWARD
INTO THE REGION THROUGH MIDWEEK BEFORE SLIDING OFFSHORE BY
THURSDAY. AN UNUSUALLY DEEP TROUGH FOR THIS TIME OF YEAR THEN
ARRIVES BY LATE IN THE WEEK BEFORE CLOSING OFF OVER THE GREAT
LAKES. OVERALL...EXPECT ONE WELL ABOVE NORMAL DAY MONDAY FOLLOWED
BY SEVERAL DAYS OF WELL BELOW NORMAL TEMPERATURES AS FLOW TURNS
ONSHORE. IN THE DAILIES...WE BEGIN THE PERIOD WITH A FRONT STALLED
TO OUR SOUTH AND WEST AS HIGH PRESSURE BUILDS BY TO OUR
NORTH...BEFORE THE HIGH SLIDES OFFSHORE ON WEDNESDAY. A WARM
WESTERLY FLOW ON MONDAY IS REPLACED BY A COOL ONSHORE FLOW FOR
TUESDAY AND WEDNESDAY. WHILE THE RIDGE WILL KEEP THE FRONT STALLED
TO OUR WEST THROUGH WEDNESDAY...THE PERSISTENT ONSHORE FLOW MAY
EVENTUALLY PRODUCE MARINE STRATUS AND DRIZZLE BY TUESDAY NIGHT OR
WEDNESDAY. WE BECOME INCREASINGLY UNSETTLED AFTER THAT AS THE
FRONTAL BOUNDARY MEANDERS EASTWARD AND THE UPPER TROUGH CLOSES OFF
TO OUR WEST.
&&
.AVIATION /04Z SUNDAY THROUGH THURSDAY/...
SHORT TERM...VFR CONDITIONS.
LONG TERM...
WED - THU...AREAS OF MVFR IN MARINE STRATUS WITH LOCAL IFR POSSIBLE
IN FOG AND DRIZZLE.
&&
.MARINE...
SHORT TERM...HAVE DROPPED SCA DUE TO SEAS AS THE SEAS ARE BELOW
SCA CRITERIA AND WILL CONTINUE TO SLOWLY SUBSIDE THE REST OF THE
NIGHT AS PER SWAN AND OTHER WAVE MODELS SUGGEST AS THE DEVELOPING
WEST FLOW KNOCKS DOWN SEAS FURTHER.
LONG TERM...
TUE - THU...SMALL CRAFT WINDS AND SEAS ARE POSSIBLE.
&&
.FIRE WEATHER...
SHOWERS TODAY HAVE LEFT HUMIDITY LEVELS HIGH AND FIRE CONCERNS LOW.
HOWEVER...DRIER CONDITIONS RETURN ON SUNDAY. WITH DEEP MIXING THE
HUMIDITY LEVELS WILL FALL TO 25 TO 30 PERCENT ON THE COASTAL SIDE
OF THE MOUNTAINS DURING THE AFTERNOON SUNDAY ALONG WITH WINDS
GUSTING TO 20 MPH. THIS BORDERLINES BUT DOES NOT EXCEED RED FLAG
WARNING CONDITIONS. SOME WETTING TODAY HAS HELPED FUEL
CONDITIONS WILL BE COORDINATING WITH MAINE LATER TODAY.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.
&&
$$
NEAR TERM UPDATE... KIMBLE
AREA FORECAST DISCUSSION
NWS GRAY ME
831 PM EDT SAT MAY 10 2014
.SYNOPSIS...
A COLD FRONT WILL STALL BRIEFLY OFFSHORE TONIGHT. HIGH PRESSURE
WILL BUILD IN FOR SUNDAY AND MONDAY. A BACK DOOR COLD FRONT TRACKS
SOUTHWEST ACROSS THE AREA MONDAY NIGHT AND TUESDAY MORNING. HIGH
PRESSURE WILL THEN BUILD IN FROM THE NORTHEAST THROUGH WEDNESDAY.
A SLOW MOVING COLD FRONT WILL MOVE IN FROM THE WEST ON THURSDAY
AND CROSS THE AREA FRIDAY. HIGH PRESSURE WILL ENTER THE REGION
NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
830 PM UPDATE: ELIMINATED ANY RISK OF SHWRS OVR SRN MOST AREAS
THIS EVENING AS SHWRS HAVE ALL MOVED S AND E OF THE AREA. DRIER
AMS WITH MUCH LOWER DEWPTS CURRENTLY ADVECTING SEWD ACROSS THE FA
ON AND A DEVELOPING LIGHT WEST SFC FLOW. NO CHNGS TO REST OF FCST
ATTM.
PREV DISC;
CLOUDS AND FOG ARE HANGING IN TOUGH OVER EASTERN AREAS LATE THIS
AFTERNOON. OTHERWISE...CLEARING AND SOMEWHAT DRIER AIR CONTINUES
TO MOVE IN FROM THE WEST. THERE IS CONVECTION OVER SOUTHERN NYS
WHICH WILL CONTINUE TO MOVE ENE PER LATEST HRRR MODEL RUN.
CONVECTION MAY BRIEFLY REACH SOUTHERNMOST PORTIONS OF THE FORECAST
AREA THIS EVENING...AND HAVE INCLUDED CHC POPS FOR THIS REGION FOR
A COUPLE HOURS.
OTHERWISE...THERE APPEARS TO BE SUFFICIENT GRADIENT OVERNIGHT TO
KEEP FOG FROM FORMING.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/...
OFFSHORE FLOW WILL ALLOW FOR WARM TEMPERATURES ON SUNDAY FOR ALL
AREAS. THIS WILL BRING TEMPERATURES IN THE 70S FOR MANY
SECTIONS...THE FIRST TIME IN QUITE A PERIOD. CYCLONIC FLOW MAY
INDUCE A COUPLE SHOWERS OVER THE FAR NRN MOUNTAINS DURING THE
LATE MORNING AND EARLY AFTERNOON HOURS.
IT WILL BE DRY SUNDAY NIGHT. HOWEVER...A BACK DOOR COLD FRONT MAY
BE APPROACHING THE REGION...RETROGRADING INTO OUR AREA FROM
NORTHEAST TO SOUTHWEST.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
MODELS ARE IN GOOD AGREEMENT THROUGH LATE NEXT WEEK ON LONGWAVE
PATTERN. THE UPPER TROUGH OVER NEW ENGLAND IS LIFTING OUT AS WE
BEGIN THE PERIOD ON MONDAY WITH UPPER RIDGE PROGRESSING EASTWARD
INTO THE REGION THROUGH MIDWEEK BEFORE SLIDING OFFSHORE BY
THURSDAY. AN UNUSUALLY DEEP TROUGH FOR THIS TIME OF YEAR THEN
ARRIVES BY LATE IN THE WEEK BEFORE CLOSING OFF OVER THE GREAT
LAKES. OVERALL...EXPECT ONE WELL ABOVE NORMAL DAY MONDAY FOLLOWED
BY SEVERAL DAYS OF WELL BELOW NORMAL TEMPERATURES AS FLOW TURNS
ONSHORE. IN THE DAILIES...WE BEGIN THE PERIOD WITH A FRONT STALLED
TO OUR SOUTH AND WEST AS HIGH PRESSURE BUILDS BY TO OUR
NORTH...BEFORE THE HIGH SLIDES OFFSHORE ON WEDNESDAY. A WARM
WESTERLY FLOW ON MONDAY IS REPLACED BY A COOL ONSHORE FLOW FOR
TUESDAY AND WEDNESDAY. WHILE THE RIDGE WILL KEEP THE FRONT STALLED
TO OUR WEST THROUGH WEDNESDAY...THE PERSISTENT ONSHORE FLOW MAY
EVENTUALLY PRODUCE MARINE STRATUS AND DRIZZLE BY TUESDAY NIGHT OR
WEDNESDAY. WE BECOME INCREASINGLY UNSETTLED AFTER THAT AS THE
FRONTAL BOUNDARY MEANDERS EASTWARD AND THE UPPER TROUGH CLOSES OFF
TO OUR WEST.
&&
.AVIATION /01Z SUNDAY THROUGH THURSDAY/...
SHORT TERM...VFR CONDS.
LONG TERM...
WED - THU...AREAS OF MVFR IN MARINE STRATUS WITH LCL IFR POSSIBLE
IN FOG AND DRIZZLE.
&&
.MARINE...
SHORT TERM...HAVE DROPPED SCA DUE TO SEAS AS THE SEAS ARE BLO SCA
CRIT AND WILL CONT TO SLOWLY SUBSIDE THE REST OF THE NIGHT AS PER
SWAN AND OTHER WAVE MODELS SUGGEST AS THE DVLPG WEST FLOW KNOCKS
DOWN SEAS FURTHER.
LONG TERM...
TUE - THU...SMALL CRAFT WINDS AND SEAS ARE POSSIBLE.
&&
.FIRE WEATHER...
SHOWERS TODAY HAVE LEFT HUMIDITY LEVELS HIGH AND FIRE CONCERNS LOW.
HOWEVER...DRIER CONDITIONS RETURN ON SUNDAY. WITH DEEP MIXING THE
HUMIDITY LEVELS WILL FALL TO 25 TO 30 PERCENT ON THE COASTAL SIDE
OF THE MOUNTAINS DURING THE AFTERNOON SUNDAY ALONG WITH WINDS
GUSTING TO 20 MPH. THIS BORDERLINES BUT DOES NOT EXCEED RED FLAG
WARNING CONDITIONS. SOME WETTING TODAY HAS HELPED FUEL
CONDITIONS WILL BE COORDINATING WITH MAINE LATER TODAY.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
933 PM EDT SAT MAY 10 2014
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE NORTHWEST THIS
EVENING...THEN SLIDE ACROSS THE REGION TONIGHT. HIGH PRESSURE
BUILDS INTO THE AREA ON SUNDAY AND WILL BECOME ANCHORED OFF THE
SOUTHEAST COAST THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
SFC HI PRES RMNS OFF THE SE CONUS CST THIS EVENING...WHICH
PROVIDED A WARM/MODERATELY HUMID AMS INTO/OVR THE RGN ON SW WNDS
THIS PAST AFTERNOON. MEANWHILE...CDFNT APPROACHING FM THE ERN OH
VALLEY...TRAILING BACK TO THE WNW TO LO PRES INVOF SD. EARLIER
SHRA/TSRA ACRS CENTRAL SECTIONS OF THE FA HAVE DISSIPATED LEAVING
ONLY A RIBBON OF SCT SHRA/TSRA OVER NE NC IN VICINITY OF AN OLD
OUTFLOW BOUNDARY.
ONCE THE SFC BOUNDARY/UPPER TROUGH CLEARS AFTER MIDNIGHT...SHOULD
SEE DRYING WEATHER RETURN ALONG WITH GRADUAL CLEARING. HANGING
ONTO SLGT CHC/LO CHC POPS INVOF SE CST THROUGH ABT 12Z/11. LO
TEMPS FM THE U50S NW TO M60S SE. THERE COULD BE SOME PATCHY FOG
ONCE THE SKY CLEARS...ESPECIALLY FOR AREAS THAT RECEIVED RAIN THIS
PAST AFTERNOON/EVENING.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
HIGH PRESSURE BUILDS IN ON SUNDAY AND SHOULD PROVIDE DRY AND WARM
CONDITIONS THROUGH MONDAY AS IT SLIDES OFF THE COAST AND UPPER
LEVEL SE US RIDGE REESTABLISHES ITSELF. SKIES AVG P/M SUNNY BOTH
DAYS. N/NW LOW LEVEL FLOW SUN MORNING DIMINISHES BY MIDDAY AS THE
SFC HIGH SLIDES OFFSHORE...ALLOWING FOR ONSHORE FLOW IN THE AFTN.
HIGHS WELL INLAND WILL REMAIN ABOVE AVG...GENLY INTO THE L/M80S...BUT
WILL LIKELY STAY IN THE 70S ALONG THE COAST AS WINDS BECOME ONSHORE.
MNLY SKC SUN NGT WITH LO TEMPS IN THE U50S TO L60S.
SFC WINDS TURN MORE TO THE SSW ON MON...A GRADUAL WARMING TREND
WILL PREVAIL WITH HIGHS BACK INTO THE MID 80S TO AROUND 90 F WELL
INLAND WITH M70S TO M 80S ON THE ERN SHORE AND RIGHT ON THE IMMEDIATE
COAST.
STRENGTH/AMPLITUDE OF RIDGE BUILD/MOVING OVR THE RGN LT SUN
THROUGH MON XPCD TO LIMIT CONVECTIVE DEVELOPMENT OVR THE RGN.
TRACK OF ANY CONVECTIVE COMPLEXES LIKELY TO RMN N OF THE RGN.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
MEDIUM RANGE MODELS ARE GENERALLY IN GOOD AGREEMENT ABOUT THE
OVERALL PATTERN EVOLVING FROM AN UPR RIDGE DOMINATING THE WEATHER
THROUGH NEXT WEDNESDAY...TO A TROUGH BECOMING ESTABLISHED BY FRIDAY.
WARM/HUMID CONDITIONS EXPECTED TO PREVAIL ACROSS MUCH OF THE AREA ON
WEDNESDAY...EXCEPT FOR THE DELMARVA WHERE A BACKDOOR COLD FRONT WILL
RESIDE. WILL TEMPER MAX TEMPS EXPECTATIONS THERE.
AS A COLD FRONT APPROACHES/CROSSES THE AREA THURSDAY/THURS NIGHT...
ENTIRE CWA SHOULD AGAIN GET INTO THE WARM SECTOR. COOLER AIRMASS
THEN MOVES IN BEHIND THE FRONT FOR FRIDAY/SATURDAY. UNSETTLED
CONDITIONS ARE EXPECTED AHEAD/WITH THE FRONT FROM WED-FRI.
MAX TEMPS GENERALLY IN THE 80S ON WED...EXCEPT COOLER 60S/70S FOR
THE DELMARVA. MAX TEMPS BY THURSDAY IN THE 70S/80S...THEN IN THE 70S
EVERYWHERE NEXT FRIDAY/SATURDAY.
&&
.AVIATION /01Z SUNDAY THROUGH THURSDAY/...
STILL DEALING WITH SOME SHOWERS MAINLY FROM KRIC SOUTH. THESE ARE
HAVE DEVELOPED AND MOVED EAST FROM A LEE SIDE TROF. THE MAIN UPPER
FEATURE IS STILL TO THE WEST OVER WEST VIRGINIA. THIS LOOKS TO
SLIDE NORTHEAST OF THE REGION OVERNIGHT. LOOKING AT THE HRRR AND
NEW RUC SHOW THE SHOWERS WITH THE UPPER SYSTEM DISSIPATING BY THE
TIME THEY WOULD REACH KRIC AROUND 06Z. WILL NOT BRING ANY OF THE
SHOWERS FROM THE WESTERN SYSTEM INTO THE TAF SITES. HOWEVER THE
CURRENT SHOWERS MOVING THROUGH THE AREA WILL CONTINUE TO THE EAST
AND AFFECT KPHF KORF AND KECG THROUGH ABOUT 03Z. EXPECT THE
HEAVIER SHOWERS AT KPHF AND KORF THIS EVENING. COULD BE AN
ISOLATED LIGHTING STILL WITH THE SHOWERS BUT DO NOT EXPECT ANY.
THINK VISIBILITY AND CEILINGS WILL DROP INTO MVFR RANGE WITH THE
SHOWERS.
AFTER THE UPPER SHORT WAVES PASSES TO THE EAST SKIES WILL BEGIN TO
CLEAR. NOT MUCH WIND OR DRYING COMING AFTER THE WAVE SO COULD SEE
SOME FOG DEVELOP ESPECIALLY AT KRIC BUT ALSO POSSIBLE KPHF AND
KSBY. NOT EXPECTING IT AT KORF AND KECG BUT WILL HAVE TO SEE WHAT
HAPPENS AFTER SKIES CLEAR LATE TONIGHT.
MOSTLY VFR CONDITIONS SUN INTO MON AS HIGH PRESSURE OVER THE
ATLANTIC RETROGRADES OVER THE ATLANTIC COAST.
&&
.MARINE...
SSW WINDS 15 KT OR LESS ARE PREVAILING ACRS THE WTRS...AND THIS WILL
CONTINUE TO BE THE CASE TODAY INTO SUN MORNG...UNTIL A WEAK COLD
FRONT MOVES THRU AND WINDS SHIFT TO THE W OR NW. HI PRES WILL BLD
OVR THE AREA DURING SUN...THEN SETS UP OFF THE MID ATLC CST FOR MON
INTO WED. WINDS WILL SHIFT FM NNE TO S FM EARLY SUN AFTN INTO LATE
SUN NGT. EXPECT S OR SW WINDS 15 KT OR LESS FOR MON THRU TUE. WAVES
1 TO 2 FT...AND SEAS 2 TO 3 FT EXPECTED FM TODAY THRU TUE.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...ALB/LKB
NEAR TERM...AJZ/ALB/LKB
SHORT TERM...ALB/LKB
LONG TERM...JDM
AVIATION...DAP/JAB
MARINE...JDM
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
733 PM EDT SAT MAY 10 2014
.SYNOPSIS...
A COLD FRONT WILL APPROACH FROM THE NORTHWEST THIS
EVENING...THEN SLIDE ACROSS THE REGION TONIGHT. HIGH PRESSURE
BUILDS INTO THE AREA ON SUNDAY AND WILL BECOME ANCHORED OFF THE
SOUTHEAST COAST THROUGH THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
SFC HI PRES RMNS OFF THE SE CONUS CST THIS AFTN...PROVIDING
WARM/MODERATELY HUMID AMS INTO/OVR THE RGN ON SW WNDS.
MEANWHILE...CDFNT APPROACHING FM THE ERN OH VALLEY...TRAILING BACK
TO THE WNW TO LO PRES INVOF SD. EARLIER MNLY SHRAS ACRS N AND NW
SECTIONS OF THE FA HAVE BECOME MORE SCT SO FAR THIS AFTN...WHILE
RIBBON OF SCT TSTMS DVLPG ACRS (MNLY) SRN/SE VA INVOF BEST
AVAILABLE INSTABILITY.
THROUGH THE EVE HRS...WILL CONT TO HAVE SCT-LIKELY POPS...ESP N OF
THE NC/VA BORDER. FEW STMS MAY BECOME STRONG ENOUGH FOR GUSTY WNDS
AND HAIL...THOUGH SVR PARAMETER WEAK/MARGINAL AT BEST. 50DBZ CORES
TO ABT 28-29KFT ALG W/ VILS ARND 50 APR TO BE ENOUGH FOR
CONSIDERATION OF SVR WX.
ONCE THE SFC BOUNDARY/UPPER TROUGH CLEARS AFTER MIDNIGHT...SHOULD
SEE DRYING WEATHER RETURN ALONG WITH GRADUAL CLEARING. HANGING
ONTO SLGT CHC/LO CHC POPS INVOF CST THROUGH ABT 12Z/11. LO TEMPS
FM THE U50S NW TO M60S SE.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
HIGH PRESSURE BUILDS IN ON SUNDAY AND SHOULD PROVIDE DRY AND WARM
CONDITIONS THROUGH MONDAY AS IT SLIDES OFF THE COAST AND UPPER
LEVEL SE US RIDGE REESTABLISHES ITSELF. SKIES AVG P/M SUNNY BOTH
DAYS. N/NW LOW LEVEL FLOW SUN MORNING DIMINISHES BY MIDDAY AS THE
SFC HIGH SLIDES OFFSHORE...ALLOWING FOR ONSHORE FLOW IN THE AFTN.
HIGHS WELL INLAND WILL REMAIN ABOVE AVG...GENLY INTO THE L/M80S...BUT
WILL LIKELY STAY IN THE 70S ALONG THE COAST AS WINDS BECOME ONSHORE.
MNLY SKC SUN NGT WITH LO TEMPS IN THE U50S TO L60S.
SFC WINDS TURN MORE TO THE SSW ON MON...A GRADUAL WARMING TREND
WILL PREVAIL WITH HIGHS BACK INTO THE MID 80S TO AROUND 90 F WELL
INLAND WITH M70S TO M 80S ON THE ERN SHORE AND RIGHT ON THE IMMEDIATE
COAST.
STRENGTH/AMPLITUDE OF RIDGE BUILD/MOVING OVR THE RGN LT SUN
THROUGH MON XPCD TO LIMIT CONVECTIVE DEVELOPMENT OVR THE RGN.
TRACK OF ANY CONVECTIVE COMPLEXES LIKELY TO RMN N OF THE RGN.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
MEDIUM RANGE MODELS ARE GENERALLY IN GOOD AGREEMENT ABOUT THE
OVERALL PATTERN EVOLVING FROM AN UPR RIDGE DOMINATING THE WEATHER
THROUGH NEXT WEDNESDAY...TO A TROUGH BECOMING ESTABLISHED BY FRIDAY.
WARM/HUMID CONDITIONS EXPECTED TO PREVAIL ACROSS MUCH OF THE AREA ON
WEDNESDAY...EXCEPT FOR THE DELMARVA WHERE A BACKDOOR COLD FRONT WILL
RESIDE. WILL TEMPER MAX TEMPS EXPECTATIONS THERE.
AS A COLD FRONT APPROACHES/CROSSES THE AREA THURSDAY/THURS NIGHT...
ENTIRE CWA SHOULD AGAIN GET INTO THE WARM SECTOR. COOLER AIRMASS
THEN MOVES IN BEHIND THE FRONT FOR FRIDAY/SATURDAY. UNSETTLED
CONDITIONS ARE EXPECTED AHEAD/WITH THE FRONT FROM WED-FRI.
MAX TEMPS GENERALLY IN THE 80S ON WED...EXCEPT COOLER 60S/70S FOR
THE DELMARVA. MAX TEMPS BY THURSDAY IN THE 70S/80S...THEN IN THE 70S
EVERYWHERE NEXT FRIDAY/SATURDAY.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
STILL DEALING WITH SOME SHOWERS MAINLY FROM KRIC SOUTH. THESE ARE
HAVE DEVELOPED AND MOVED EAST FROM A LEE SIDE TROF. THE MAIN UPPER
FEATURE IS STILL TO THE WEST OVER WEST VIRGINIA. THIS LOOKS TO
SLIDE NORTHEAST OF THE REGION OVERNIGHT. LOOKING AT THE HRRR AND
NEW RUC SHOW THE SHOWERS WITH THE UPPER SYSTEM DISSIPATING BY THE
TIME THEY WOULD REACH KRIC AROUND 06Z. WILL NOT BRING ANY OF THE
SHOWERS FROM THE WESTERN SYSTEM INTO THE TAF SITES. HOWEVER THE
CURRENT SHOWERS MOVING THROUGH THE AREA WILL CONTINUE TO THE EAST
AND AFFECT KPHF KORF AND KECG THROUGH ABOUT 03Z. EXPECT THE
HEAVIER SHOWERS AT KPHF AND KORF THIS EVENING. COULD BE AN
ISOLATED LIGHTING STILL WITH THE SHOWERS BUT DO NOT EXPECT ANY.
THINK VISIBILITY AND CEILINGS WILL DROP INTO MVFR RANGE WITH THE
SHOWERS.
AFTER THE UPPER SHORT WAVES PASSES TO THE EAST SKIES WILL BEGIN TO
CLEAR. NOT MUCH WIND OR DRYING COMING AFTER THE WAVE SO COULD SEE
SOME FOG DEVELOP ESPECIALLY AT KRIC BUT ALSO POSSIBLE KPHF AND
KSBY. NOT EXPECTING IT AT KORF AND KECG BUT WILL HAVE TO SEE WHAT
HAPPENS AFTER SKIES CLEAR LATE TONIGHT.
MOSTLY VFR CONDITIONS SUN INTO MON AS HIGH PRESSURE OVER THE
ATLANTIC RETROGRADES OVER THE ATLANTIC COAST.
&&
.MARINE...
SSW WINDS 15 KT OR LESS ARE PREVAILING ACRS THE WTRS...AND THIS WILL
CONTINUE TO BE THE CASE TODAY INTO SUN MORNG...UNTIL A WEAK COLD
FRONT MOVES THRU AND WINDS SHIFT TO THE W OR NW. HI PRES WILL BLD
OVR THE AREA DURING SUN...THEN SETS UP OFF THE MID ATLC CST FOR MON
INTO WED. WINDS WILL SHIFT FM NNE TO S FM EARLY SUN AFTN INTO LATE
SUN NGT. EXPECT S OR SW WINDS 15 KT OR LESS FOR MON THRU TUE. WAVES
1 TO 2 FT...AND SEAS 2 TO 3 FT EXPECTED FM TODAY THRU TUE.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...ALB/LKB
NEAR TERM...ALB/LKB
SHORT TERM...ALB/LKB
LONG TERM...JDM
AVIATION...DAP/JAB
MARINE...JDM
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
400 PM EDT FRI MAY 9 2014
.SHORT TERM...THIS EVENING AND TONIGHT
CLOUDS AND SHALLOW EARLY AFTERNOON CONVECTION HAVE RESULTED IN A
RATHER NEBULOUS PICTURE FOR THUNDERSTORM POTENTIAL THIS EVENING.
ABUNDANT MID AND HIGH CLOUDS HAVE LIMITED BOUNDARY LAYER RECOVERY IN
THE WAKE OF THE PASSING CONVECTION, ALTHOUGH MID 70S TEMPS AND
DEWPOINTS AROUND 60 ARE MAKING A RENEWED PUSH INTO SOUTHWEST LOWER
MICHIGAN DURING THE MID AFTN AND CLOUD OPACITY IS DECREASING.
MESOANALYSIS SHOWS MUCAPES AT A RATHER MODEST 500 J/KG OVER WESTERN
LOWER FOR NOW...BUT THE 12Z NAM AND RECENT RUNS OF THE RUC SUGGEST A
RECOVERY TO 1000 J/KG CAPE BY AROUND 22Z IN ADVANCE OF THE
APPROACHING COLD FRONT. THE OVERZEALOUS HANDLING OF QPF BY TODAY`S
NWP MAKES THE PROGGED RECOVERY ALL THE MORE IMPRESSIVE. HOWEVER, IN
AND AN ATTEMPT TO ADDRESS UNCERTAINTIES REGARDING BOTH THE MID-LEVEL
AND LOW-LEVEL THERMODYNAMIC ENVIRONMENT RESULTING FROM BOTH POOR
MODEL PERFORMANCE AND EARLY CONVECTION, A SPECIAL SOUNDING WAS
LAUNCHED AT APPROXIMATELY 1930Z. THE DATA WILL BECOME AVAILABLE
SHORTLY AFTER ISSUANCE OF THE AFTERNOON PACKAGE. FINALLY, ALTHOUGH
ANY CONVECTION THAT BUBBLES UP IN ADVANCE OF THE FRONT MAY BEGIN TO
LOOSE FOOTING IN THE BOUNDARY LAYER AROUND 00Z...STEEPENING
MID-LEVEL LAPSE RATES WILL MAINTAIN RESPECTABLE MID-LEVEL
INSTABILITY WELL INTO THE EVENING HOURS AND MAY EVEN ALLOW A HAIL
THREAT TO DEVELOP IN ADDITION TO WIND AS UPDRAFTS ARE ALLOWED TO
DEEPEN. WIDESPREAD SEVERE WEATHER IS NOT EXPECTED...PARTICULARLY
GIVEN PARALLEL NATURE OF THE MEAN FLOW TO THE INITIATING
BOUNDARY...BUT AT LEAST A MARGINAL THREAT WILL EXIST DEPENDING ON
THE BEHAVIOR OF INDIVIDUAL CELLS. WILL MAINTAIN CHANCE POPS
THROUGH THE EVENING HOURS AND MENTION A RISK OF AT LEAST ISOLATED
WIND/HAIL THREATS DEVELOPING OVER THE NEXT SEVERAL HOURS IN THE HWO.
THE GREATEST THREAT WILL BE FOCUSED FURTHER SOUTH AND WEST WHERE
INSTABILITY WILL BE MAXIMIZED.
&&
.LONG TERM...
DIFFERENTIAL HEIGHT RISES BEHIND THE DEPARTING SHARP MIDLEVEL
TROUGH AXIS WILL LEAD TO A SURFACE RIDGE ACROSS SOUTHEASTERN
MICHIGAN ON SATURDAY. DRYING SIGNAL IN THE 925-850MB LAYER SUPPORTS
THE FORECAST SOUNDINGS OF LCL HEIGHTS EVENTUALLY REACHING A VERY
HIGH 6000 FT AGL. THE ENVIRONMENT FAVORABEL FOR DEEP TURBULUENT
MIXING WILL EVENTUALLY ALLOW BREEZY WESTERLIES TO DEVELOPM DURING
THE LATE AFTERNOON. SURFACE WIND GUSTS ARE EXPECTED TO REACH 25 TO
30 KNOTS. FORECASTED SOUNDINGS FOR SATURDAY ARE NOW QUITE A BIT
DIFFERENT WITH ANY EXPECTED MIDLEVEL LAPSE RATES. IN FACT...POCKET
OF STEEP MIDLEVEL LAPSE RATES IS NOWHERE TO BE SEEN...SUGGESTING
THAT EVEN A SCATTERED CU FIELD WILL BE DIFFICULT. HIGHS SATURDAY
WILL BE COOLER...READING REACHING THE UPPER 60S FOR MANY AREAS...72
OR 73 DEGREES FOR THE HIGHER SURFACE PRESSURE/LOWER TERRAIN
LOCATIONS ACROSS THE EXTREME SOUTHEAST.
THE INBOUND LONGWAVE RIDGE WILL BE VERY PROGRESSIVE DURING THE
LATTER HALF OF THE WEEKEND...AMPLIFYING AS WELL. PRECEDING MID TO
UPPER LEVEL TROPSOPHERIC DEFORMATION IS PROGGED TO BE VERY GOOD
WHICH WILL AID IN THE RAPID DEVELOPMENT OF A WARM FRONT BY SUNDAY.
EARLY PART OF THE DAY IS EXPECTED TO BE QUIET WITH VERY DRY AIR IN
RESIDENCE DURING THE MORNING. WIND TRAJECTORIES WILL EVENTUALLY VEER
SOUTHWESTERLY WHICH WILL ALLOW WARMTH AND INSTABILITY TO INCREASE
FOR THE AFTERNOON. THE SUNDAY PERIOD HAS BEEN A NOISY ONE WITHIN THE
MODELS SO CONFIDENCE IS NOT OVERLY HIGH...ESPECIALLY WITH REGARDS TO
TIMING. HOWEVER...ENOUGH UPPER LEVEL FORCING APPEARS TO BE COMING
TOGETHER SUPPORTIVE OF A MID CHANCE POP IN THUNDERSTORMS FOR THE
SOUTHERN HALF OF THE CWA. THE LATE AFTERNOON PUSH WITH WARMTH WILL
ALLOW TEMPERATURES TO REACH THE MID 70S FOR MANY LOCATIONS.
MONDAY WILL BEGIN A PERIOD OF ACTIVE WEATHER FOR THE EXTENDED AS A
WARM FRONT LIFTS NORTH INTO THE TRI CITIES AREA. AGAIN...WARM AND
MOIST AIR WILL ADVECT NORTH VIA A 40KT H85 JET. THIS WILL BRING PWAT
VALUES OVER 1.5 INCHES. WILL CONTINUE TO TREND UPWARD WITH POPS 50
TO 60 PERCENT. THE COLD FRONT WILL SWING THROUGH ON TUESDAY AND
CONTINUE THE HIGH POP EVENT. BOTH DAYS POSE THE THREAT FOR THUNDER
AS LI/S WILL BE NEGATIVE. MUCH LIKE THE PAST 2 DAYS HERE...MONDAY IN
THE WARM SECTOR WILL REMAIN CAPPED BUT WITH CAPE WELL OVER 2500
J/KG. TUESDAY WILL HAVE MORE POTENTIAL WITH THE STRONGER
FORCING...BUT LOWER CAPE VALUES. CHANCE POPS WILL ALSO BE IN THE
FORECAST WEDNESDAY AS REMNANT MOISTURE FROM THE SLOW CHURNING LOW
PRESSURE REMAINS PROXIMAL TO THE AREA. THIS WILL BE ALONG WITH A
GENERAL THUNDER THREAT. THE REST OF THE PERIOD STILL LOOKS TO REMAIN
COOL WITH TEMPS BELOW CLIMO.
&&
.MARINE...
A STRONGLY STABLE PROFILE OVER THE GREAT LAKES WILL KEEP WIND GUSTS
MAINLY UNDER 30 KNOTS. THE COLD FRONT WILL TRACK ACROSS LAKE HURON
THIS EVENING AND WILL BE MARKED BY A VEERING OF THE WIND TO THE
SOUTHWEST. THE POST FRONTAL COLD AIR ADVECTION IN THE WAKE OF THE
FRONT WILL NOT BE SIGNIFICANT ENOUGH TO OVERCOME THE STRONG OVER
LAKE STABILITY. THUS WINDS WILL REMAIN MAINLY UNDER 25 KNOTS ON
SATURDAY. WINDS WILL QUICKLY DIMINISH SATURDAY NIGHT AS SFC HIGH
PRESSURE MOVES OVER THE LAKES. A WARM FRONT WILL SLOWLY LIFT ACROSS
THE REGION SUN NIGHT THROUGH MONDAY NIGHT. THE CONTINUED STRONG
STABILITY WILL KEEP WINDS AND WAVES IN CHECK. HOWEVER...THERE WILL
BE A GOOD CHANCE FOR THUNDERSTORMS THROUGH THE PERIOD.
&&
.AVIATION...ISSUED 1251 PM EDT FRI MAY 9 2014
//DISCUSSION...
SHODDY COVERAGE OF PRECIPITATION ACROSS THE LOWER PENINSULA THIS
MORNING WILL SUPPORT AN INCREASED RISK OF INSTABILITY CAPABLE OF
SUPPORTING ADDITIONAL SHOWER AND THUNDERSTORM DEVELOPMENT THIS
AFTERNOON. INITIAL BAND OF SHOWERS LIFTING ACROSS SOUTHEAST MICHIGAN
AROUND 17Z WILL EXIT THE AREA SHORTLY AND WILL BE FOLLOWED BY A LULL
PRIMARILY CONSISTING OF VFR...OCCASIONAL LIGHT RAINFALL...AND
POCKETS OF LOW VFR CEILING. REDEVELOPMENT IS EXPECTED MID-AFTERNOON
WITH AN INCREASED RISK OF SOME STORMS BECOMING STRONG TO SEVERE.
GUSTY SOUTH-SOUTHWEST FLOW WILL PERSIST THROUGH THE EVENING BEFORE
VEERING TO A MORE WESTERLY DIRECTION IN THE WAKE OF THE COLD FRONT
AFTER 00Z.
//DTW THRESHOLD THREATS...
* MEDIUM CONFIDENCE IN CEILINGS BELOW 5KFT
* MEDIUM CONFIDENCE THAT TSTORMS WILL IMPACT KDTW
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.
&&
$$
SHORT TERM...JVC
LONG TERM....CB/MM
MARINE.......CB
AVIATION.....JVC
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
346 PM EDT FRI MAY 9 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 444 AM EDT FRI MAY 9 2014
THE UPPER TROUGH THAT HAS BEEN CONTROLLING OUR WEATHER FOR THE LAST
COUPLE OF DAYS IS CURRENTLY MOVING NORTHEAST THROUGH THE CENTRAL
PLAINS. MOISTURE LADEN AIR STREAMING NORTHEAST AHEAD OF THIS TROUGH
CAN BE SEEN ON WV IMAGERY EARLY THIS MORNING...WHICH IS HELPING TO
FUEL SHOWERS AND ISOLATED THUNDERSTORMS FROM WESTERN LAKE SUPERIOR
THROUGH PORTIONS OF UPPER MICHIGAN...AND SOUTHEAST TO EASTERN
WISCONSIN. AT THE SURFACE...A 998MB LOW IS LOCATED JUST SOUTHWEST OF
DULUTH AND A WARM FRONT STRETCHES EAST ALONG THE U.P. AND
WISCONSIN BORDER. SHORTWAVES EMBEDDED WITHIN THE WARM MOIST
SOUTHWESTERLY FLOW CONTINUES TO PRODUCE AREAS OF THUNDERSTORMS OVER
THE WESTERN HALF OF THE GREAT LAKES REGION AND EXPECT THAT TO
CONTINUE FOR AREAS WITHIN THE WARM/MOIST AIRMASS.
AS THE LOW LIFTS NORTHEAST TODAY...THE COLD FRONT (CURRENTLY
STRETCHING SOUTH FROM SOUTHEAST MINNESOTA THROUGH NORTHERN
MISSOURI) WILL SWEEP NORTHEAST ACROSS THE UPPER GREAT LAKES REGION.
WITH THE SHOWER/THUNDERSTORM COVERAGE STARTING TO BECOME MORE
SCATTERED/ISOLATED...WILL FOLLOW THAT IDEA FOR POPS AHEAD OF THE
COLD FRONT. ALREADY STARTING TO SEE THE AFFECT OF THE DRYING ALOFT
OVER NORTHWEST WISCONSIN AND EXPECT THE LAST AREAS OF SHOWERS FOR
THIS MORNING TO PUSH THROUGH WESTERN UPPER MICHIGAN OVER THE NEXT
COUPLE OF HOURS. AS THAT DRYING SHIFTS EAST THIS MORNING...WILL
DIMINISH POPS FROM WEST TO EAST DURING THE MORNING HOURS. WITH
THERE STILL BEING SOME ISOLATED THUNDER ON THE BACK EDGE OF THE
PRECIPITATION (EVEN THOUGH RAP ANALYSIS OF MUCAPE AND MID-LEVEL
LAPSE RATE VALUES ARE VERY WEAK)...HAVE EXTENDED THE SLIGHT
CHANCE OF THUNDER A LITTLE LONGER OVER THE EAST THIS MORNING TO
COINCIDE WITH THE AXIS OF MOISTURE AND LATEST THUNDER
AREAS.
BEHIND THE COLD FRONT...MAY SEE A FEW PEAKS OF SUNSHINE OVER THE
CENTRAL/EAST (WHERE FOG ISN/T OCCURRING) AS THIS MID LEVEL DRY SLOT
MOVES THROUGH AND BEFORE THE NEXT WAVE OF LOW LEVEL MOISTURE AND
PRECIPITATION (CURRENTLY IN THE EASTERN DAKOTAS AND WESTERN
MINNESOTA) MOVES OVER THE AREA. WILL CONTINUE THE IDEA SHOWN IN THE
PREVIOUS FORECAST OF ISOLATED TO SCATTERED SHOWERS MOVING OVER THE
WEST OR NORTHWEST HALF OF THE CWA LATER THIS AFTERNOON AND
CONTINUING THROUGH A GOOD PORTION OF THE NIGHT TONIGHT (ESPECIALLY
THE KEWEENAW TONIGHT). QPF AMOUNTS WILL BE MUCH LIGHTER THAN SEEN
OVER THE LAST COUPLE DAYS AND MAINLY BETWEEN A TRACE AND A COUPLE
TENTHS. IN ADDITION...IT WILL BECOME BREEZY BEHIND THE COLD
FRONT...WITH BUFKIT SOUNDINGS INDICATING GUSTS AROUND 25KTS OVER
MUCH MUCH OF UPPER MICHIGAN TODAY. WITH THE COLD AIR ADVECTION IN
PLACE THROUGH MUCH OF TONIGHT...THOSE GUSTS WILL LIKELY KEEP UP AS
WINDS SHIFT TO THE WEST THROUGH THE NIGHT. WHILE THE KEWEENAW MAY BE
PROTECTED SLIGHTLY TODAY...THE WINDS SHOULD REALLY KICK IN TONIGHT
AS IT IS CLOSEST TO THE TIGHTEST PRESSURE GRADIENT WITH THE
DEPARTING LOW AND RESULTING STRONGER WINDS JUST ABOVE THE SURFACE.
EXPECT THERE TO BE A PERIOD THIS EVENING AND INTO THE EARLY
OVERNIGHT HOURS WHERE GUSTS IN THE KEWEENAW WILL BE BETWEEN
30-35KTS.
FINALLY FOR TEMPERATURES...VALUES THIS MORNING HAVE BEEN CONSISTENT
IN THE 50S OVER THE INTERIOR LOCATIONS...ALTHOUGH LOCATIONS NEAR
THE COOLING OF THE GREAT LAKES HAVE BEEN BOUNCING UP AND DOWN
DEPENDING ON THE WIND DIRECTION. WITH THE WARM START AND THE WARM
FRONT PUSHING NORTHEAST THROUGH MUCH OF UPPER MICHIGAN
TODAY...SHOULD SEE TEMPERATURES RISE INTO THE MID-UPPER 60S OVER
THE CENTRAL/EASTERN CWA AND WHERE SOME SUNSHINE OCCURS WILL
PROBABLY SEE SOME SITES HITTING THE 70 DEGREE MARK. COLDER AIR
ARRIVING BEHIND THE COLD FRONT WILL LEAD TO FALLING TEMPS OVER THE
WEST IN THE AFTERNOON AND THE REST OF THE AREA TOWARDS EVENING. THE
CLOUD COVER TONIGHT WILL KEEP TEMPS A LITTLE ABOVE NORMAL AND HAVE
LOWS IN THE LOWER 40S.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 343 PM EDT FRI MAY 9 2014
MAIN FCST CONCERNS FOR LATER IN THE WEEKEND INVOLVE POPS ASSOCIATED
WITH SHRTWV FCST TO LIFT INTO THE UPR LKS SAT NGT INTO SUN OUT OF A
DEEPENING TROF OVER THE W. A MORE IMPORTANT/WETTER LO PRES IS LIKELY
TO IMPACT THE AREA ON MON INTO TUE WITH INCRSG SW FLOW ALF BTWN THE
DEEPENING UPR TROF IN THE PLAINS AND BLDG UPR RDG OVER THE SE CONUS.
SAT NGT/SUN...SHRTWV EJECTING OUT OF A DEEPENING UPR TROF OVER THE W
IS FCST TO BE MOVING THRU SW MN AT 00Z SUN INTO THE UPR LKS BY 12Z
SUN. BUT SINCE AN UPR RDG AXIS IS FCST TO SHARPEN OVER UPR MI TO THE
NW OF BLDG MEAN RDG OVER THE SE CONUS AND ON SW FLANK OF MORE
PERSISTENT TROFFING OVER SE CANADA THAT WL MAINTAIN A SOURCE OF LLVL
DRY AIR...SUSPECT SHRA ASSOCIATED WITH THE SHRTWV APRCHG FM THE SW
WL DIMINISH WITH TIME AND TOWARDS THE NE. IN FACT...BULK OF MODELS
SHOW DIMINISHING DEEP LYR QVECTOR CNVGC/MID LVL RH AS THE SHRTWV
MOVES THRU UPR MI. MAINTAINED FLAVOR OF GOING FCST SHOWING ARRIVAL
OF CHC POPS FM THE SW ON SAT NGT BUT THEN DIMINISHING AS SHOWER
AREA MOVES TO THE NE ON SUN.
SUN NGT...AS STRONGER SHRTWV BEGINS TO EJECT OUT OF DEEPENING UPR
TROF MOVING SLOWLY THRU THE ROCKIES...SFC LO PRES IS FCST TO
ORGANIZE IN THE CENTRAL PLAINS TO THE SW OF SFC HI PRES EXTENDING FM
FAR NW ONTARIO INTO THE UPR LKS. ALTHOUGH THE EVNG MAY BE DRY
ESPECIALLY OVER THE N HALF OF THE CWA CLOSER TO DRY LLVL NE
TRAJECTORIES OUT OF THE HI IN ONTARIO...MOST OF THE MODELS SHOW HIER
MID LVL RH/SOME PCPN ARRIVING FM THE SW THRU THE NGT WITH SOME
ISENTROPIC ASCENT N OF H85 WARM FNT FCST TO REACH SRN WI BY 12Z MON.
WL MAINTAIN HI CHC/LIKELY POPS NEAR THE WI BORDER LATE AT NGT...
WITH DCRSG POPS TO THE N TOWARD THE DRIER AIR. TENDED TO SHARPEN THE
GRADIENT OF THE POPS ON THE NRN EDGE OF THE PCPN SHIELD TO REFLECT
THE IMPACT OF THIS DRY AIR.
MON THRU TUE...SHRTWV EJECTING OUT OF HI AMPLITUDE UPR TROF SHIFTING
SLOWLY EWD INTO THE PLAINS WL CAUSE SFC LO IN THE CENTRAL PLAINS AT
12Z MON TO LIFT NNEWD AND THRU MN ON TUE. MODELS APPEAR TO BE
MAINTAINING TREND TOWARD A SLOWER...FARTHER W TRACK FOR THE SFC
LO...NOT SURPRISING CONSIDERING THE HI AMPLITUDE PLAINS TROF/ERN RDG
PATTERN TAKING SHAPE. SINCE THE SFC LO IS TRENDING TO MOVE SLOWER TO
THE NE AND THE UPR RDG IS STILL BLDG INTO THE GREAT LKS ON MON...
SUSPECT WDSPRD WAD RA WL BE SLOWER TO MOVE N THRU THE CWA TO THE N
OF WARM FNT HUNG UP TO THE S. WHEN THE SFC LO FINALLY SHIFTS TO THE
N ON MON NGT/TUE...MORE WDPSRD SHRA/EVEN SOME TS ARE LIKELY TO MOVE
N WITH H85 WARM FROPA/H85 TEMPS RISING TO 14C OVER THE SE CWA. ANY
TS WL BE ELEVATED AS LONGER RANGE MODELS SHOW SFC WARM FNT REMAINING
TO THE S WITH TRIPLE PT LO SHIFTING THRU NW LOWER MI TO THE SE OF
OCCLUDED LO MOVING THRU MN. WITH PWAT FCST TO REACH 1.25-1.50 INCH/
UP TO 225 PCT OF NORMAL...HEAVY RA MAY FALL DURING THIS EVENT AND
CAUSE RIVER LVLS TO RISE AGAIN. DRIER AIR ALF WL MOVE IN FM THE WSW
ON TUE FOLLOWING OCCLUDED FROPA AND DIMINISH THE POPS.
EXTENDED...AS SLOW MOVING UPR TROF SWINGS INTO THE GREAT LKS ON WED
INTO FRI...A VERY COOL AIRMASS WITH H85 TEMPS AS LO AS -5C WL IMPACT
UPR MI WX. WITH THE PASSAGE OF SEVERAL SHRTWVS AND A MOIST CYC
FLOW...SOME -SHRA...MIXED WITH SOME SN...WL BE PSBL. SO MAINTAINED
LO CHC POPS SHOWN BY THE MODEL CONSENSUS. PCPN DURING THE DAY SHOULD
SHIFT TO MAINLY OVER THE INTERIOR AS THE COOLER LKS WL ACT AS A
STABILIZING IFNLUENCE. BLO NORMAL TEMPS WL BE THE RULE.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 139 PM EDT FRI MAY 9 2014
LOW PRESSURE TRACKING JUST NE OF UPPER MI WILL BRING A COLD FRONT
WEST TO EAST ACROSS ALL SITES THIS AFTERNOON AND EVENING. ABUNDANT
LOW-LEVEL MOISTURE AND UPSLOPE FLOW SHOULD RESULT IN IFR CIGS AT CMX
AND IWD OVERNIGHT ALONG WITH -SHRA. DOWNSLOPE FLOW WILL LIMIT SAW TO
MVFR CIGS. EXPECT ALL SITES TO BECOME VFR WITH CLEAR SKIES BY SAT
MORNING AS DRY AIR PUSHES ACROSS THE AREA. DECENT MIXING AND
STRONGER WINDS ALOFT WILL BRING GUSTY WINDS TO ALL SITES INTO
SAT...ESPECIALLY FOR CMX...WHERE GUSTS OVER 30KTS WILL BE POSSIBLE
LATE THIS EVENING THROUGH THE OVERNIGHT HOURS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 422 AM EDT FRI MAY 9 2014
A LOW PRESSURE SYSTEM NEAR DULUTH EARLY THIS MORNING WILL SLIDE
NORTHEAST INTO ONTARIO TODAY. AS THIS OCCURS...WINDS WILL SHIFT
AROUND TO THE SOUTHWESTERLY DIRECTION TODAY AND THEN TO THE WEST
TONIGHT. EXPECT THE WINDS TO INCREASE FROM WEST TO EAST TODAY AND
GENERALLY TO 25KTS TONIGHT...ALTHOUGH THERE COULD BE SOME GUSTS
TO 30KTS OVER THE CENTRAL LAKE. THESE STRONGER WINDS...COMBINED WITH
GRADUALLY DRYING LOWER LEVELS SHOULD LEAD TO A DIMINISHMENT OF THE
DENSE FOG OVER LAKE SUPERIOR FROM SOUTHWEST TO NORTHEAST TODAY.
OPTED TO EXTENDED THE DENSE FOG ADVISORY FOR LAKE SUPERIOR INTO THE
AFTERNOON HOURS TO BETTER MATCH UP WITH THE INCREASING WINDS AND
DRIER AIR. A HIGH PRESSURE RIDGE WILL THEN SLIDE OVER THE AREA ON
SATURDAY AND LEAD TO WINDS FALLING BELOW 15KTS SATURDAY NIGHT. THESE
LIGHT WINDS WILL REMAIN THROUGH SUNDAY EVENING. A LOW PRESSURE
SYSTEM MOVING TOWARDS THE UPPER GREAT LAKES REGION FROM THE CENTRAL
PLAINS ON SUNDAY NIGHT WILL LEAD TO INCREASING EASTERLY WINDS (TO
25KTS BY MONDAY EVENING). THEN AS THE LOW SHIFTS NORTHEAST INTO
ONTARIO ON TUESDAY...WINDS WILL SHIFT TO THE SOUTHWEST AND STAY
BELOW 20KTS.
&&
.HYDROLOGY...
ISSUED AT 343 PM EDT FRI MAY 9 2014
RUNOFF FROM RECENT HEAVY RAIN...THAT REACHED UP TO AN INCH OR TWO AT
SOME PLACES OVER NW UPR MI THE PAST FEW DAYS...AND MELTING OF THE
LINGERING SNOW PACK OVER THE HIER TERRAIN ACCELERATED BY THE ARRIVAL
OF WARMER...RATHER HUMID AIR /SFC DEWPTS IN THE 50S/ HAVE CAUSED
AREA RIVER LEVELS TO RISE AGAIN...ESPECIALLY OVER THE W HALF OF UPR
MI. THE TRAP ROCK RIVER IN HOUGHTON COUNTY ROSE ABOVE FLOOD STAGE
EARLY THIS MRNG TO THE HIEST LEVEL ON RECORD /10.8 FT/...AND THE
STURGEON RIVER AT ALSTON AND CHASSELL ARE ALSO ABOVE BANKFULL.
FORTUNATELY...ONLY SOME SCATTERED LIGHT SHOWERS ARE IN THE FORECAST
FOR TONIGHT AND SAT NIGHT INTO SUN...WITH A DRY DAY FOR MOST ON SAT.
SINCE THE TRAP ROCK IS A NOTORIOUSLY FAST RESPONDING STREAM...THIS
RIVER HAS ALREADY FALLEN BELOW FLOOD STAGE AS THE SHORTER TERM HEAVY
RAIN RUNOFF HAS ALREADY FLOWED THROUGH THAT BODY OF WATER. BUT
ADDITIONAL RUNOFF FROM PAST RAIN AND THE MELT DOWN OF THE REST OF
THE SNOW PACK WILL ALLOW SLOWER RESPONDING RIVERS TO CONTINUE RISING
INTO THE WEEKEND. THE ADVISORIES FOR THE STURGEON RIVER AT ALSTON
AND CHASSELL ARE IN EFFECT INTO SUN. OVERALL...STREAMS AND RIVERS
WILL REMAIN HI INTO NEXT WEEK...WITH ADDITIONAL HEAVY RA POSSIBLE ON
MON INTO TUE. THOSE LIVING NEAR RIVERS...CREEKS...AND STREAMS SHOULD
CONTINUE TO MONITOR RIVER LEVELS IN CASE ADDITIONAL FLOOD WARNINGS
OR ADVISORIES ARE NECESSARY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 5 PM EDT /4 PM CDT/ THIS AFTERNOON FOR
LSZ162-240>251-263>267.
LAKE MICHIGAN...
DENSE FOG ADVISORY UNTIL 6 PM EDT THIS EVENING FOR LMZ248-250.
&&
$$
SHORT TERM...SRF
LONG TERM...KC
AVIATION...KLUBER
MARINE...SRF
HYDROLOGY...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
140 PM EDT FRI MAY 9 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 444 AM EDT FRI MAY 9 2014
THE UPPER TROUGH THAT HAS BEEN CONTROLLING OUR WEATHER FOR THE LAST
COUPLE OF DAYS IS CURRENTLY MOVING NORTHEAST THROUGH THE CENTRAL
PLAINS. MOISTURE LADEN AIR STREAMING NORTHEAST AHEAD OF THIS TROUGH
CAN BE SEEN ON WV IMAGERY EARLY THIS MORNING...WHICH IS HELPING TO
FUEL SHOWERS AND ISOLATED THUNDERSTORMS FROM WESTERN LAKE SUPERIOR
THROUGH PORTIONS OF UPPER MICHIGAN...AND SOUTHEAST TO EASTERN
WISCONSIN. AT THE SURFACE...A 998MB LOW IS LOCATED JUST SOUTHWEST OF
DULUTH AND A WARM FRONT STRETCHES EAST ALONG THE U.P. AND
WISCONSIN BORDER. SHORTWAVES EMBEDDED WITHIN THE WARM MOIST
SOUTHWESTERLY FLOW CONTINUES TO PRODUCE AREAS OF THUNDERSTORMS OVER
THE WESTERN HALF OF THE GREAT LAKES REGION AND EXPECT THAT TO
CONTINUE FOR AREAS WITHIN THE WARM/MOIST AIRMASS.
AS THE LOW LIFTS NORTHEAST TODAY...THE COLD FRONT (CURRENTLY
STRETCHING SOUTH FROM SOUTHEAST MINNESOTA THROUGH NORTHERN
MISSOURI) WILL SWEEP NORTHEAST ACROSS THE UPPER GREAT LAKES REGION.
WITH THE SHOWER/THUNDERSTORM COVERAGE STARTING TO BECOME MORE
SCATTERED/ISOLATED...WILL FOLLOW THAT IDEA FOR POPS AHEAD OF THE
COLD FRONT. ALREADY STARTING TO SEE THE AFFECT OF THE DRYING ALOFT
OVER NORTHWEST WISCONSIN AND EXPECT THE LAST AREAS OF SHOWERS FOR
THIS MORNING TO PUSH THROUGH WESTERN UPPER MICHIGAN OVER THE NEXT
COUPLE OF HOURS. AS THAT DRYING SHIFTS EAST THIS MORNING...WILL
DIMINISH POPS FROM WEST TO EAST DURING THE MORNING HOURS. WITH
THERE STILL BEING SOME ISOLATED THUNDER ON THE BACK EDGE OF THE
PRECIPITATION (EVEN THOUGH RAP ANALYSIS OF MUCAPE AND MID-LEVEL
LAPSE RATE VALUES ARE VERY WEAK)...HAVE EXTENDED THE SLIGHT
CHANCE OF THUNDER A LITTLE LONGER OVER THE EAST THIS MORNING TO
COINCIDE WITH THE AXIS OF MOISTURE AND LATEST THUNDER
AREAS.
BEHIND THE COLD FRONT...MAY SEE A FEW PEAKS OF SUNSHINE OVER THE
CENTRAL/EAST (WHERE FOG ISN/T OCCURRING) AS THIS MID LEVEL DRY SLOT
MOVES THROUGH AND BEFORE THE NEXT WAVE OF LOW LEVEL MOISTURE AND
PRECIPITATION (CURRENTLY IN THE EASTERN DAKOTAS AND WESTERN
MINNESOTA) MOVES OVER THE AREA. WILL CONTINUE THE IDEA SHOWN IN THE
PREVIOUS FORECAST OF ISOLATED TO SCATTERED SHOWERS MOVING OVER THE
WEST OR NORTHWEST HALF OF THE CWA LATER THIS AFTERNOON AND
CONTINUING THROUGH A GOOD PORTION OF THE NIGHT TONIGHT (ESPECIALLY
THE KEWEENAW TONIGHT). QPF AMOUNTS WILL BE MUCH LIGHTER THAN SEEN
OVER THE LAST COUPLE DAYS AND MAINLY BETWEEN A TRACE AND A COUPLE
TENTHS. IN ADDITION...IT WILL BECOME BREEZY BEHIND THE COLD
FRONT...WITH BUFKIT SOUNDINGS INDICATING GUSTS AROUND 25KTS OVER
MUCH MUCH OF UPPER MICHIGAN TODAY. WITH THE COLD AIR ADVECTION IN
PLACE THROUGH MUCH OF TONIGHT...THOSE GUSTS WILL LIKELY KEEP UP AS
WINDS SHIFT TO THE WEST THROUGH THE NIGHT. WHILE THE KEWEENAW MAY BE
PROTECTED SLIGHTLY TODAY...THE WINDS SHOULD REALLY KICK IN TONIGHT
AS IT IS CLOSEST TO THE TIGHTEST PRESSURE GRADIENT WITH THE
DEPARTING LOW AND RESULTING STRONGER WINDS JUST ABOVE THE SURFACE.
EXPECT THERE TO BE A PERIOD THIS EVENING AND INTO THE EARLY
OVERNIGHT HOURS WHERE GUSTS IN THE KEWEENAW WILL BE BETWEEN
30-35KTS.
FINALLY FOR TEMPERATURES...VALUES THIS MORNING HAVE BEEN CONSISTENT
IN THE 50S OVER THE INTERIOR LOCATIONS...ALTHOUGH LOCATIONS NEAR
THE COOLING OF THE GREAT LAKES HAVE BEEN BOUNCING UP AND DOWN
DEPENDING ON THE WIND DIRECTION. WITH THE WARM START AND THE WARM
FRONT PUSHING NORTHEAST THROUGH MUCH OF UPPER MICHIGAN
TODAY...SHOULD SEE TEMPERATURES RISE INTO THE MID-UPPER 60S OVER
THE CENTRAL/EASTERN CWA AND WHERE SOME SUNSHINE OCCURS WILL
PROBABLY SEE SOME SITES HITTING THE 70 DEGREE MARK. COLDER AIR
ARRIVING BEHIND THE COLD FRONT WILL LEAD TO FALLING TEMPS OVER THE
WEST IN THE AFTERNOON AND THE REST OF THE AREA TOWARDS EVENING. THE
CLOUD COVER TONIGHT WILL KEEP TEMPS A LITTLE ABOVE NORMAL AND HAVE
LOWS IN THE LOWER 40S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 459 AM EDT FRI MAY 9 2014
PATTERN EVOLUTION DURING THE LONG TERM WILL BRING A RETURN OF A
BUILDING RIDGE ALONG/NEAR THE W COAST OF NAMERICA THIS WEEKEND THRU
THE FIRST HALF OF NEXT WEEK (POSITIVE ANOMALIES REACH THEIR MAX
WED). THIS WILL FORCE A FAIRLY DEEP TROF FOR MID MAY TO AMPLIFY
SOUTHWARD INTO THE CNTRL CONUS DURING THE EARLY PART OF NEXT WEEK
WITH SLOW EASTWARD PROGRESSION THEREAFTER. THE BUILDING RIDGE WILL
FORCE THE UPPER LOW/ENERGY NOW IN THE GULF OF ALASKA TO DIVE SE
TOWARD THE SRN ROCKIES. AS THE ENERGY THEN LIFTS NE...ANOTHER ACTIVE
LOW PRES SYSTEM WILL MOVE NE INTO THE UPPER MISSISSIPPI VALLEY ON A
TRACK SIMILAR TO THE SYSTEM CURRENTLY AFFECTING THE MISSISSIPPI
VALLEY/WRN GREAT LAKES. SO...AFTER A PERIOD OF DRY WEATHER EARLY IN
THE WEEKEND...POTENTIAL OF SHRA WILL RETURN...PERHAPS AS EARLY AS
LATE SAT NIGHT/SUN MORNING. DECENT PCPN AMOUNTS MAY THEN BE IN THE
OFFING FOR MON/MON NIGHT AS LOW PRES LIFTS INTO THE UPPER
MISSISSIPPI VALLEY. ONCE THE UPPER TROF REACHES THE WRN GREAT
LAKES...THERE MAY BE A DAY OR 2 OF LIGHT SHOWERY PCPN AT TIMES IN
THE MID WEEK PERIOD (PERHAPS EVEN A LITTLE SNOW MIXED IN). AS FOR
TEMPS...READINGS OVER THE WEEKEND SHOULD BE CLOSE TO NORMAL...
THOUGH IT WILL OBVIOUSLY BE COOL WHERE WINDS ARE ONSHORE NEAR THE
GREAT LAKES. TEMPS WILL BEGIN TO TAKE A DOWNWARD TURN MON/TUE WITH
THE EARLY WEEK LOW PRES SYSTEM...AND TEMPS WED/THU WILL LIKELY BE
QUITE CHILLY/WELL BLO NORMAL FOR MID MAY AS UPPER TROF DRIFTS ACROSS
THE AREA (850MB TEMPS FALL TO PERHAPS AS LOW AS -4 TO -6C). FARTHER
DOWN THE ROAD...PATTERN WILL PROBABALY CONTINUE TO LEAN TOWARD
MAINTAINING OVERALL BLO NORMAL TEMPS OUT TO 10-14 DAYS.
BEGINNING SAT...LOW CLOUDS AND POSSIBLY SOME -SHRA/SPRINKLES/-DZ
WILL LINGER EARLY OVER THE E. OTHERWISE...EXPECT ABUNDANT SUNSHINE
OVER THE W TO SPREAD TO THE ERN FCST AREA BY AFTN AS FCST SOUNDINGS
SHOW A DEEP DRY AIR MASS SPREADING OVER THE AREA. DRY AIR MASS WILL
ALLOW FOR DEEP MIXING. MIXING UPWARDS OF 750MB ON FCST SOUNDINGS
YIELDS MAX TEMPS INTO THE MID TO PERHAPS UPPER 60S IN THE INTERIOR.
TEMPS WILL BE COOLEST ALONG LAKE SUPERIOR IN LOCATIONS WHERE
WESTERLY WINDS HAVE AN OVERLAKE COMPONENT. LAKE BREEZE MAY DEVELOP
NEAR LAKE MICHIGAN IN THE LATTER PART OF THE AFTN. WITH THE DEEP DRY
AIR MASS...RH WILL LIKELY TUMBLE TO AS LOW AS AROUND 20PCT IN THE
INTERIOR...IN PARTICULAR TOWARD THE WI BORDER.
OUT AHEAD OF THE MAIN SYSTEM DIVING TOWARD THE SRN ROCKIES...A LEAD
SHORTWAVE WILL SHIFT FROM THE WRN PLAINS SAT MORNING TO THE UPPER
LAKES SUN MORNING. GIVEN THAT THE SHORTWAVE WILL BE HEADING INTO THE
LARGE SCALE BUILDING UPPER RIDGE DOWNSTREAM OF THE MAIN TROF
AMPLIFYING OVER THE ROCKIES...PCPN ASSOCIATED WITH SHORTWAVE WILL
LIKELY BE DIMINISHING AS IT MOVES INTO THE UPPER LAKES. ANTECEDENT
VERY DRY AIR MASS WILL FURTHER AID THE DIMINISHING OF PCPN SPREADING
INTO THE AREA LATE SAT NIGHT/SUN MORNING. QUESTION WILL BE HOW FAST
DOES THE PCPN DECAY. AT THIS POINT...IT APPEARS THE GFS IS MUCH TOO
AGGRESSIVE WITH WIDESPREAD PCPN IT MOVES ACROSS THE FCST AREA WITH
AS MUCH AS 0.25-0.40 INCHES OVER ROUGHLY THE NW HALF OF UPPER MI.
OTHER GUIDANCE IS DRIER WITH PCPN DRYING UP AS IT MOVES INTO/ACROSS
THE THE FCST AREA. THE NAM IN PARTICULAR HAS ALMOST NO PCPN REACHING
UPPER MI. WILL FAVOR THE DRIER SOLUTIONS GIVEN BUILDING UPPER RIDGE
AND ANTECEDENT DRY AIR MASS. ONLY CHC POPS WILL BE UTILIZED LATE SAT
NIGHT THRU SUN MORNING WITH POPS LOWEST OVER THE NE. CLOUD
COVER/PCPN WILL HAVE AN IMPACT ON HIGH TEMPS SUN. IN FAVORING THE
DRIER SOLUTIONS...WILL ALSO LEAN TOWARD THE WARMER GUIDANCE FOR
HIGHS SUN. AWAY FROM LAKE MODERATION...TEMPS SHOULD REACH WELL INTO
THE 60S TO NEAR 70F.
MAIN SHORTWAVE MOVES OUT ACROSS THE SRN PLAINS MON MORNING AND LIFTS
INTO THE UPPER MISSISSIPPI VALLEY MON NIGHT/TUE ALONG WITH
ASSOCIATED SFC LOW PRES. THERE IS CONSIDERABLE MODEL SPREAD ON
TIMING SYSTEM WITH SOME HINTS OF A SLOWER TREND DEVELOPING. THE
UKMET IS SLOWEST...SHOWING LOW PRES ONLY IN WCNTRL WI AT 00Z WED.
NEXT IS THE GEM...SWINGING FROPA THRU UPPER MI TUE AFTN-TUE NIGHT.
THE ECMWF BRINGS FRONT THRU MON NIGHT/TUE MORNING WHILE THE GFS IS
QUICKEST...PUSHING FRONT ACROSS THE AREA MON EVENING. CONSENSUS OF
RECENT RUNS WILL BE UTILIZED GIVEN SPREAD. AT THIS TIME...BEST
CHANCE OF SHRA SOME TSRA APPEARS TO BE MON/MON NIGHT...BUT IF SLOWER
TREND GAINS MOMENTUM...TIMING WILL NEED TO BE PUSHED BACK A BIT.
AS UPPER TROF DRIFTS ACROSS THE WRN LAKES WED/THU...THERMAL TROF
WITH 850MB TEMPS IN THE -2 TO -6C RANGE WILL YIELD ABUNDANT CLOUD
COVER...ESPECIALLY DURING THE DAYLIGHT HRS. HIGH SUN ANGLE (ONLY 5
1/2 WEEKS TO THE SUMMER SOLSTICE DURING THE MIDDLE OF NEXT WEEK)
WILL PROBABLY SUPPORT AT LEAST SCT -SHRA ACTIVITY...PEAKING IN THE
AFTN HRS. GIVEN THE COLD TEMPS IN THE COLUMN...MAY SEE SOME
GRAUPLE...AND PERHAPS EVEN SOME SNOWFLAKES IF PCPN LINGERS INTO THE
NIGHT. IF WED OR THU ENDS UP MAINLY CLOUDY WITH NMRS -SRHA...HIGH
TEMPS MAY STRUGGLE TO GET INTO THE 50S INLAND WHILE DAYTIME TEMPS
MAY HOLD TO THE MID 30S TO MID 40S NEAR LAKE SUPERIOR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 139 PM EDT FRI MAY 9 2014
LOW PRESSURE TRACKING JUST NE OF UPPER MI WILL BRING A COLD FRONT
WEST TO EAST ACROSS ALL SITES THIS AFTERNOON AND EVENING. ABUNDANT
LOW-LEVEL MOISTURE AND UPSLOPE FLOW SHOULD RESULT IN IFR CIGS AT CMX
AND IWD OVERNIGHT ALONG WITH -SHRA. DOWNSLOPE FLOW WILL LIMIT SAW TO
MVFR CIGS. EXPECT ALL SITES TO BECOME VFR WITH CLEAR SKIES BY SAT
MORNING AS DRY AIR PUSHES ACROSS THE AREA. DECENT MIXING AND
STRONGER WINDS ALOFT WILL BRING GUSTY WINDS TO ALL SITES INTO
SAT...ESPECIALLY FOR CMX...WHERE GUSTS OVER 30KTS WILL BE POSSIBLE
LATE THIS EVENING THROUGH THE OVERNIGHT HOURS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 422 AM EDT FRI MAY 9 2014
A LOW PRESSURE SYSTEM NEAR DULUTH EARLY THIS MORNING WILL SLIDE
NORTHEAST INTO ONTARIO TODAY. AS THIS OCCURS...WINDS WILL SHIFT
AROUND TO THE SOUTHWESTERLY DIRECTION TODAY AND THEN TO THE WEST
TONIGHT. EXPECT THE WINDS TO INCREASE FROM WEST TO EAST TODAY AND
GENERALLY TO 25KTS TONIGHT...ALTHOUGH THERE COULD BE SOME GUSTS
TO 30KTS OVER THE CENTRAL LAKE. THESE STRONGER WINDS...COMBINED WITH
GRADUALLY DRYING LOWER LEVELS SHOULD LEAD TO A DIMINISHMENT OF THE
DENSE FOG OVER LAKE SUPERIOR FROM SOUTHWEST TO NORTHEAST TODAY.
OPTED TO EXTENDED THE DENSE FOG ADVISORY FOR LAKE SUPERIOR INTO THE
AFTERNOON HOURS TO BETTER MATCH UP WITH THE INCREASING WINDS AND
DRIER AIR. A HIGH PRESSURE RIDGE WILL THEN SLIDE OVER THE AREA ON
SATURDAY AND LEAD TO WINDS FALLING BELOW 15KTS SATURDAY NIGHT. THESE
LIGHT WINDS WILL REMAIN THROUGH SUNDAY EVENING. A LOW PRESSURE
SYSTEM MOVING TOWARDS THE UPPER GREAT LAKES REGION FROM THE CENTRAL
PLAINS ON SUNDAY NIGHT WILL LEAD TO INCREASING EASTERLY WINDS (TO
25KTS BY MONDAY EVENING). THEN AS THE LOW SHIFTS NORTHEAST INTO
ONTARIO ON TUESDAY...WINDS WILL SHIFT TO THE SOUTHWEST AND STAY
BELOW 20KTS.
&&
.HYDROLOGY...
ISSUED AT 456 AM EDT FRI MAY 9 2014
THE RAIN SHOWERS AND THUNDERSTORMS PRODUCING HEAVY RAIN HAVE
NEARLY DEPARTED UPPER MICHIGAN EARLY THIS MORNING. BUT THEY HAVE
LEFT RISING RIVER LEVELS IN THEIR WAKE...ESPECIALLY OVER WESTERN
UPPER MICHIGAN WHERE THE HEAVIEST RAIN HAS FALLEN. THE KEWEENAW
PENINSULA HAS SEEN AROUND 0.75 INCHES OVERNIGHT IN ADDITION TO THE
INCH OF RAIN THAT FELL LAST NIGHT. THIS AS LED TO ANOTHER RISE OF
THE TRAP ROCK RIVER OVER THE LAST COUPLE OF HOURS. IT HAS LEVELED
OUT SOMEWHAT OVER THE LAST HOUR...BUT WITH A COUPLE HOURS LEFT
OF RAIN AND SNOW MELT CONTINUING WOULD EXPECT A LITTLE MORE RISE
THIS MORNING. IT DID BRIEFLY REACH 10.15FT...WHICH PUTS THE CURRENT
CREST AT THE 4TH HIGHEST ON RECORD.
WARM TEMPERATURES TODAY WILL CONTINUE THE MELTING FROM A FEW INCHES
OF SNOW WATER EQUIVALENT SHOWN FROM NOHRSC MODEL FROM THE
TIP OF THE KEWEENAW PENINSULA THROUGH PAINESDALE...DONKEN...AND
WINONA. THIS LINES UP WELL WITH THE LATEST SNOW DEPTHS REPORTED AT
PAINESDALE AND HERMAN. WILL SEE HOW THIS SNOW MELT /WARMER FCST
TEMPS FOR THE REST OF THIS WEEK/ IMPACT DOWNSTREAM RIVERS INCLUDING
THE STURGEON RIVER OF BARAGA/HOUGHTON COUNTIES AND THE TRAP ROCK
RIVER. MOST IF NOT ALL OF THE SNOW COULD MELT BY THIS
WEEKEND...BUT IT WILL KEEP THE RIVER LEVELS HIGH INTO EARLY NEXT
WEEK. IN ADDITION...WIDESPREAD RAIN IS EXPECTED AGAIN ON
MONDAY AND THE CURRENT FORECAST CALLS FOR AROUND A HALF AN INCH
OF ACCUMULATION. THOSE LIVING AROUND RIVERS...CREEKS...AND STREAMS
SHOULD CONTINUE TO MONITOR RIVER LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 5 PM EDT /4 PM CDT/ THIS AFTERNOON FOR
LSZ162-240>251-263>267.
LAKE MICHIGAN...
DENSE FOG ADVISORY UNTIL 6 PM EDT THIS EVENING FOR LMZ248-250.
&&
$$
SHORT TERM...SRF
LONG TERM...ROLFSON
AVIATION...KLUBER
MARINE...SRF
HYDROLOGY...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
501 AM EDT FRI MAY 9 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 444 AM EDT FRI MAY 9 2014
THE UPPER TROUGH THAT HAS BEEN CONTROLLING OUR WEATHER FOR THE LAST
COUPLE OF DAYS IS CURRENTLY MOVING NORTHEAST THROUGH THE CENTRAL
PLAINS. MOISTURE LADEN AIR STREAMING NORTHEAST AHEAD OF THIS TROUGH
CAN BE SEEN ON WV IMAGERY EARLY THIS MORNING...WHICH IS HELPING TO
FUEL SHOWERS AND ISOLATED THUNDERSTORMS FROM WESTERN LAKE SUPERIOR
THROUGH PORTIONS OF UPPER MICHIGAN...AND SOUTHEAST TO EASTERN
WISCONSIN. AT THE SURFACE...A 998MB LOW IS LOCATED JUST SOUTHWEST OF
DULUTH AND A WARM FRONT STRETCHES EAST ALONG THE U.P. AND
WISCONSIN BORDER. SHORTWAVES EMBEDDED WITHIN THE WARM MOIST
SOUTHWESTERLY FLOW CONTINUES TO PRODUCE AREAS OF THUNDERSTORMS OVER
THE WESTERN HALF OF THE GREAT LAKES REGION AND EXPECT THAT TO
CONTINUE FOR AREAS WITHIN THE WARM/MOIST AIRMASS.
AS THE LOW LIFTS NORTHEAST TODAY...THE COLD FRONT (CURRENTLY
STRETCHING SOUTH FROM SOUTHEAST MINNESOTA THROUGH NORTHERN
MISSOURI) WILL SWEEP NORTHEAST ACROSS THE UPPER GREAT LAKES REGION.
WITH THE SHOWER/THUNDERSTORM COVERAGE STARTING TO BECOME MORE
SCATTERED/ISOLATED...WILL FOLLOW THAT IDEA FOR POPS AHEAD OF THE
COLD FRONT. ALREADY STARTING TO SEE THE AFFECT OF THE DRYING ALOFT
OVER NORTHWEST WISCONSIN AND EXPECT THE LAST AREAS OF SHOWERS FOR
THIS MORNING TO PUSH THROUGH WESTERN UPPER MICHIGAN OVER THE NEXT
COUPLE OF HOURS. AS THAT DRYING SHIFTS EAST THIS MORNING...WILL
DIMINISH POPS FROM WEST TO EAST DURING THE MORNING HOURS. WITH
THERE STILL BEING SOME ISOLATED THUNDER ON THE BACK EDGE OF THE
PRECIPITATION (EVEN THOUGH RAP ANALYSIS OF MUCAPE AND MID-LEVEL
LAPSE RATE VALUES ARE VERY WEAK)...HAVE EXTENDED THE SLIGHT
CHANCE OF THUNDER A LITTLE LONGER OVER THE EAST THIS MORNING TO
COINCIDE WITH THE AXIS OF MOISTURE AND LATEST THUNDER
AREAS.
BEHIND THE COLD FRONT...MAY SEE A FEW PEAKS OF SUNSHINE OVER THE
CENTRAL/EAST (WHERE FOG ISN/T OCCURRING) AS THIS MID LEVEL DRY SLOT
MOVES THROUGH AND BEFORE THE NEXT WAVE OF LOW LEVEL MOISTURE AND
PRECIPITATION (CURRENTLY IN THE EASTERN DAKOTAS AND WESTERN
MINNESOTA) MOVES OVER THE AREA. WILL CONTINUE THE IDEA SHOWN IN THE
PREVIOUS FORECAST OF ISOLATED TO SCATTERED SHOWERS MOVING OVER THE
WEST OR NORTHWEST HALF OF THE CWA LATER THIS AFTERNOON AND
CONTINUING THROUGH A GOOD PORTION OF THE NIGHT TONIGHT (ESPECIALLY
THE KEWEENAW TONIGHT). QPF AMOUNTS WILL BE MUCH LIGHTER THAN SEEN
OVER THE LAST COUPLE DAYS AND MAINLY BETWEEN A TRACE AND A COUPLE
TENTHS. IN ADDITION...IT WILL BECOME BREEZY BEHIND THE COLD
FRONT...WITH BUFKIT SOUNDINGS INDICATING GUSTS AROUND 25KTS OVER
MUCH MUCH OF UPPER MICHIGAN TODAY. WITH THE COLD AIR ADVECTION IN
PLACE THROUGH MUCH OF TONIGHT...THOSE GUSTS WILL LIKELY KEEP UP AS
WINDS SHIFT TO THE WEST THROUGH THE NIGHT. WHILE THE KEWEENAW MAY BE
PROTECTED SLIGHTLY TODAY...THE WINDS SHOULD REALLY KICK IN TONIGHT
AS IT IS CLOSEST TO THE TIGHTEST PRESSURE GRADIENT WITH THE
DEPARTING LOW AND RESULTING STRONGER WINDS JUST ABOVE THE SURFACE.
EXPECT THERE TO BE A PERIOD THIS EVENING AND INTO THE EARLY
OVERNIGHT HOURS WHERE GUSTS IN THE KEWEENAW WILL BE BETWEEN
30-35KTS.
FINALLY FOR TEMPERATURES...VALUES THIS MORNING HAVE BEEN CONSISTENT
IN THE 50S OVER THE INTERIOR LOCATIONS...ALTHOUGH LOCATIONS NEAR
THE COOLING OF THE GREAT LAKES HAVE BEEN BOUNCING UP AND DOWN
DEPENDING ON THE WIND DIRECTION. WITH THE WARM START AND THE WARM
FRONT PUSHING NORTHEAST THROUGH MUCH OF UPPER MICHIGAN
TODAY...SHOULD SEE TEMPERATURES RISE INTO THE MID-UPPER 60S OVER
THE CENTRAL/EASTERN CWA AND WHERE SOME SUNSHINE OCCURS WILL
PROBABLY SEE SOME SITES HITTING THE 70 DEGREE MARK. COLDER AIR
ARRIVING BEHIND THE COLD FRONT WILL LEAD TO FALLING TEMPS OVER THE
WEST IN THE AFTERNOON AND THE REST OF THE AREA TOWARDS EVENING. THE
CLOUD COVER TONIGHT WILL KEEP TEMPS A LITTLE ABOVE NORMAL AND HAVE
LOWS IN THE LOWER 40S.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 459 AM EDT FRI MAY 9 2014
PATTERN EVOLUTION DURING THE LONG TERM WILL BRING A RETURN OF A
BUILDING RIDGE ALONG/NEAR THE W COAST OF NAMERICA THIS WEEKEND THRU
THE FIRST HALF OF NEXT WEEK (POSITIVE ANOMALIES REACH THEIR MAX
WED). THIS WILL FORCE A FAIRLY DEEP TROF FOR MID MAY TO AMPLIFY
SOUTHWARD INTO THE CNTRL CONUS DURING THE EARLY PART OF NEXT WEEK
WITH SLOW EASTWARD PROGRESSION THEREAFTER. THE BUILDING RIDGE WILL
FORCE THE UPPER LOW/ENERGY NOW IN THE GULF OF ALASKA TO DIVE SE
TOWARD THE SRN ROCKIES. AS THE ENERGY THEN LIFTS NE...ANOTHER ACTIVE
LOW PRES SYSTEM WILL MOVE NE INTO THE UPPER MISSISSIPPI VALLEY ON A
TRACK SIMILAR TO THE SYSTEM CURRENTLY AFFECTING THE MISSISSIPPI
VALLEY/WRN GREAT LAKES. SO...AFTER A PERIOD OF DRY WEATHER EARLY IN
THE WEEKEND...POTENTIAL OF SHRA WILL RETURN...PERHAPS AS EARLY AS
LATE SAT NIGHT/SUN MORNING. DECENT PCPN AMOUNTS MAY THEN BE IN THE
OFFING FOR MON/MON NIGHT AS LOW PRES LIFTS INTO THE UPPER
MISSISSIPPI VALLEY. ONCE THE UPPER TROF REACHES THE WRN GREAT
LAKES...THERE MAY BE A DAY OR 2 OF LIGHT SHOWERY PCPN AT TIMES IN
THE MID WEEK PERIOD (PERHAPS EVEN A LITTLE SNOW MIXED IN). AS FOR
TEMPS...READINGS OVER THE WEEKEND SHOULD BE CLOSE TO NORMAL...
THOUGH IT WILL OBVIOUSLY BE COOL WHERE WINDS ARE ONSHORE NEAR THE
GREAT LAKES. TEMPS WILL BEGIN TO TAKE A DOWNWARD TURN MON/TUE WITH
THE EARLY WEEK LOW PRES SYSTEM...AND TEMPS WED/THU WILL LIKELY BE
QUITE CHILLY/WELL BLO NORMAL FOR MID MAY AS UPPER TROF DRIFTS ACROSS
THE AREA (850MB TEMPS FALL TO PERHAPS AS LOW AS -4 TO -6C). FARTHER
DOWN THE ROAD...PATTERN WILL PROBABALY CONTINUE TO LEAN TOWARD
MAINTAINING OVERALL BLO NORMAL TEMPS OUT TO 10-14 DAYS.
BEGINNING SAT...LOW CLOUDS AND POSSIBLY SOME -SHRA/SPRINKLES/-DZ
WILL LINGER EARLY OVER THE E. OTHERWISE...EXPECT ABUNDANT SUNSHINE
OVER THE W TO SPREAD TO THE ERN FCST AREA BY AFTN AS FCST SOUNDINGS
SHOW A DEEP DRY AIR MASS SPREADING OVER THE AREA. DRY AIR MASS WILL
ALLOW FOR DEEP MIXING. MIXING UPWARDS OF 750MB ON FCST SOUNDINGS
YIELDS MAX TEMPS INTO THE MID TO PERHAPS UPPER 60S IN THE INTERIOR.
TEMPS WILL BE COOLEST ALONG LAKE SUPERIOR IN LOCATIONS WHERE
WESTERLY WINDS HAVE AN OVERLAKE COMPONENT. LAKE BREEZE MAY DEVELOP
NEAR LAKE MICHIGAN IN THE LATTER PART OF THE AFTN. WITH THE DEEP DRY
AIR MASS...RH WILL LIKELY TUMBLE TO AS LOW AS AROUND 20PCT IN THE
INTERIOR...IN PARTICULAR TOWARD THE WI BORDER.
OUT AHEAD OF THE MAIN SYSTEM DIVING TOWARD THE SRN ROCKIES...A LEAD
SHORTWAVE WILL SHIFT FROM THE WRN PLAINS SAT MORNING TO THE UPPER
LAKES SUN MORNING. GIVEN THAT THE SHORTWAVE WILL BE HEADING INTO THE
LARGE SCALE BUILDING UPPER RIDGE DOWNSTREAM OF THE MAIN TROF
AMPLIFYING OVER THE ROCKIES...PCPN ASSOCIATED WITH SHORTWAVE WILL
LIKELY BE DIMINISHING AS IT MOVES INTO THE UPPER LAKES. ANTECEDENT
VERY DRY AIR MASS WILL FURTHER AID THE DIMINISHING OF PCPN SPREADING
INTO THE AREA LATE SAT NIGHT/SUN MORNING. QUESTION WILL BE HOW FAST
DOES THE PCPN DECAY. AT THIS POINT...IT APPEARS THE GFS IS MUCH TOO
AGGRESSIVE WITH WIDESPREAD PCPN IT MOVES ACROSS THE FCST AREA WITH
AS MUCH AS 0.25-0.40 INCHES OVER ROUGHLY THE NW HALF OF UPPER MI.
OTHER GUIDANCE IS DRIER WITH PCPN DRYING UP AS IT MOVES INTO/ACROSS
THE THE FCST AREA. THE NAM IN PARTICULAR HAS ALMOST NO PCPN REACHING
UPPER MI. WILL FAVOR THE DRIER SOLUTIONS GIVEN BUILDING UPPER RIDGE
AND ANTECEDENT DRY AIR MASS. ONLY CHC POPS WILL BE UTILIZED LATE SAT
NIGHT THRU SUN MORNING WITH POPS LOWEST OVER THE NE. CLOUD
COVER/PCPN WILL HAVE AN IMPACT ON HIGH TEMPS SUN. IN FAVORING THE
DRIER SOLUTIONS...WILL ALSO LEAN TOWARD THE WARMER GUIDANCE FOR
HIGHS SUN. AWAY FROM LAKE MODERATION...TEMPS SHOULD REACH WELL INTO
THE 60S TO NEAR 70F.
MAIN SHORTWAVE MOVES OUT ACROSS THE SRN PLAINS MON MORNING AND LIFTS
INTO THE UPPER MISSISSIPPI VALLEY MON NIGHT/TUE ALONG WITH
ASSOCIATED SFC LOW PRES. THERE IS CONSIDERABLE MODEL SPREAD ON
TIMING SYSTEM WITH SOME HINTS OF A SLOWER TREND DEVELOPING. THE
UKMET IS SLOWEST...SHOWING LOW PRES ONLY IN WCNTRL WI AT 00Z WED.
NEXT IS THE GEM...SWINGING FROPA THRU UPPER MI TUE AFTN-TUE NIGHT.
THE ECMWF BRINGS FRONT THRU MON NIGHT/TUE MORNING WHILE THE GFS IS
QUICKEST...PUSHING FRONT ACROSS THE AREA MON EVENING. CONSENSUS OF
RECENT RUNS WILL BE UTILIZED GIVEN SPREAD. AT THIS TIME...BEST
CHANCE OF SHRA SOME TSRA APPEARS TO BE MON/MON NIGHT...BUT IF SLOWER
TREND GAINS MOMENTUM...TIMING WILL NEED TO BE PUSHED BACK A BIT.
AS UPPER TROF DRIFTS ACROSS THE WRN LAKES WED/THU...THERMAL TROF
WITH 850MB TEMPS IN THE -2 TO -6C RANGE WILL YIELD ABUNDANT CLOUD
COVER...ESPECIALLY DURING THE DAYLIGHT HRS. HIGH SUN ANGLE (ONLY 5
1/2 WEEKS TO THE SUMMER SOLSTICE DURING THE MIDDLE OF NEXT WEEK)
WILL PROBABLY SUPPORT AT LEAST SCT -SHRA ACTIVITY...PEAKING IN THE
AFTN HRS. GIVEN THE COLD TEMPS IN THE COLUMN...MAY SEE SOME
GRAUPLE...AND PERHAPS EVEN SOME SNOWFLAKES IF PCPN LINGERS INTO THE
NIGHT. IF WED OR THU ENDS UP MAINLY CLOUDY WITH NMRS -SRHA...HIGH
TEMPS MAY STRUGGLE TO GET INTO THE 50S INLAND WHILE DAYTIME TEMPS
MAY HOLD TO THE MID 30S TO MID 40S NEAR LAKE SUPERIOR.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 128 AM EDT FRI MAY 9 2014
SHOWERS AND SCT TSRA WILL LIFT TO THE NE THROUGH UPPER MICHIGAN
OVERNIGHT. AS A RESULT...LOW LEVEL MOISTENING FROM THE RAIN AND S TO
SE FLOW WILL KEEP OR DROP CIGS INTO THE IFR/LIFR RANGE TONIGHT.
CONDITIONS WILL IMPROVE FRI MORNING AS WINDS BECOME SW AND GREATER
DRYING/MIXING MOVES IN. A BRIEF PERIOD OF VFR CONDITIONS MAY DEVELOP
BY AFTERNOON BUT LOWER MVFR CIGS ARE EXPECTED TO REDEVELOP OVER THE
WEST AS ADDITIONAL MOISTURE WRAPS AROUND THE DEPARTING LOW PRESSURE
SYSTEM.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 422 AM EDT FRI MAY 9 2014
A LOW PRESSURE SYSTEM NEAR DULUTH EARLY THIS MORNING WILL SLIDE
NORTHEAST INTO ONTARIO TODAY. AS THIS OCCURS...WINDS WILL SHIFT
AROUND TO THE SOUTHWESTERLY DIRECTION TODAY AND THEN TO THE WEST
TONIGHT. EXPECT THE WINDS TO INCREASE FROM WEST TO EAST TODAY AND
GENERALLY TO 25KTS TONIGHT...ALTHOUGH THERE COULD BE SOME GUSTS
TO 30KTS OVER THE CENTRAL LAKE. THESE STRONGER WINDS...COMBINED WITH
GRADUALLY DRYING LOWER LEVELS SHOULD LEAD TO A DIMINISHMENT OF THE
DENSE FOG OVER LAKE SUPERIOR FROM SOUTHWEST TO NORTHEAST TODAY.
OPTED TO EXTENDED THE DENSE FOG ADVISORY FOR LAKE SUPERIOR INTO THE
AFTERNOON HOURS TO BETTER MATCH UP WITH THE INCREASING WINDS AND
DRIER AIR. A HIGH PRESSURE RIDGE WILL THEN SLIDE OVER THE AREA ON
SATURDAY AND LEAD TO WINDS FALLING BELOW 15KTS SATURDAY NIGHT. THESE
LIGHT WINDS WILL REMAIN THROUGH SUNDAY EVENING. A LOW PRESSURE
SYSTEM MOVING TOWARDS THE UPPER GREAT LAKES REGION FROM THE CENTRAL
PLAINS ON SUNDAY NIGHT WILL LEAD TO INCREASING EASTERLY WINDS (TO
25KTS BY MONDAY EVENING). THEN AS THE LOW SHIFTS NORTHEAST INTO
ONTARIO ON TUESDAY...WINDS WILL SHIFT TO THE SOUTHWEST AND STAY
BELOW 20KTS.
&&
.HYDROLOGY...
ISSUED AT 456 AM EDT FRI MAY 9 2014
THE RAIN SHOWERS AND THUNDERSTORMS PRODUCING HEAVY RAIN HAVE
NEARLY DEPARTED UPPER MICHIGAN EARLY THIS MORNING. BUT THEY HAVE
LEFT RISING RIVER LEVELS IN THEIR WAKE...ESPECIALLY OVER WESTERN
UPPER MICHIGAN WHERE THE HEAVIEST RAIN HAS FALLEN. THE KEWEENAW
PENINSULA HAS SEEN AROUND 0.75 INCHES OVERNIGHT IN ADDITION TO THE
INCH OF RAIN THAT FELL LAST NIGHT. THIS AS LED TO ANOTHER RISE OF
THE TRAP ROCK RIVER OVER THE LAST COUPLE OF HOURS. IT HAS LEVELED
OUT SOMEWHAT OVER THE LAST HOUR...BUT WITH A COUPLE HOURS LEFT
OF RAIN AND SNOW MELT CONTINUING WOULD EXPECT A LITTLE MORE RISE
THIS MORNING. IT DID BRIEFLY REACH 10.15FT...WHICH PUTS THE CURRENT
CREST AT THE 4TH HIGHEST ON RECORD.
WARM TEMPERATURES TODAY WILL CONTINUE THE MELTING FROM A FEW INCHES
OF SNOW WATER EQUIVALENT SHOWN FROM NOHRSC MODEL FROM THE
TIP OF THE KEWEENAW PENINSULA THROUGH PAINESDALE...DONKEN...AND
WINONA. THIS LINES UP WELL WITH THE LATEST SNOW DEPTHS REPORTED AT
PAINESDALE AND HERMAN. WILL SEE HOW THIS SNOW MELT /WARMER FCST
TEMPS FOR THE REST OF THIS WEEK/ IMPACT DOWNSTREAM RIVERS INCLUDING
THE STURGEON RIVER OF BARAGA/HOUGHTON COUNTIES AND THE TRAP ROCK
RIVER. MOST IF NOT ALL OF THE SNOW COULD MELT BY THIS
WEEKEND...BUT IT WILL KEEP THE RIVER LEVELS HIGH INTO EARLY NEXT
WEEK. IN ADDITION...WIDESPREAD RAIN IS EXPECTED AGAIN ON
MONDAY AND THE CURRENT FORECAST CALLS FOR AROUND A HALF AN INCH
OF ACCUMULATION. THOSE LIVING AROUND RIVERS...CREEKS...AND STREAMS
SHOULD CONTINUE TO MONITOR RIVER LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 5 PM EDT /4 PM CDT/ THIS AFTERNOON FOR
LSZ162-240>251-263>267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...ROLFSON
AVIATION...JLB
MARINE...SRF
HYDROLOGY...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
457 AM EDT FRI MAY 9 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 444 AM EDT FRI MAY 9 2014
THE UPPER TROUGH THAT HAS BEEN CONTROLLING OUR WEATHER FOR THE LAST
COUPLE OF DAYS IS CURRENTLY MOVING NORTHEAST THROUGH THE CENTRAL
PLAINS. MOISTURE LADEN AIR STREAMING NORTHEAST AHEAD OF THIS TROUGH
CAN BE SEEN ON WV IMAGERY EARLY THIS MORNING...WHICH IS HELPING TO
FUEL SHOWERS AND ISOLATED THUNDERSTORMS FROM WESTERN LAKE SUPERIOR
THROUGH PORTIONS OF UPPER MICHIGAN...AND SOUTHEAST TO EASTERN
WISCONSIN. AT THE SURFACE...A 998MB LOW IS LOCATED JUST SOUTHWEST OF
DULUTH AND A WARM FRONT STRETCHES EAST ALONG THE U.P. AND
WISCONSIN BORDER. SHORTWAVES EMBEDDED WITHIN THE WARM MOIST
SOUTHWESTERLY FLOW CONTINUES TO PRODUCE AREAS OF THUNDERSTORMS OVER
THE WESTERN HALF OF THE GREAT LAKES REGION AND EXPECT THAT TO
CONTINUE FOR AREAS WITHIN THE WARM/MOIST AIRMASS.
AS THE LOW LIFTS NORTHEAST TODAY...THE COLD FRONT (CURRENTLY
STRETCHING SOUTH FROM SOUTHEAST MINNESOTA THROUGH NORTHERN
MISSOURI) WILL SWEEP NORTHEAST ACROSS THE UPPER GREAT LAKES REGION.
WITH THE SHOWER/THUNDERSTORM COVERAGE STARTING TO BECOME MORE
SCATTERED/ISOLATED...WILL FOLLOW THAT IDEA FOR POPS AHEAD OF THE
COLD FRONT. ALREADY STARTING TO SEE THE AFFECT OF THE DRYING ALOFT
OVER NORTHWEST WISCONSIN AND EXPECT THE LAST AREAS OF SHOWERS FOR
THIS MORNING TO PUSH THROUGH WESTERN UPPER MICHIGAN OVER THE NEXT
COUPLE OF HOURS. AS THAT DRYING SHIFTS EAST THIS MORNING...WILL
DIMINISH POPS FROM WEST TO EAST DURING THE MORNING HOURS. WITH
THERE STILL BEING SOME ISOLATED THUNDER ON THE BACK EDGE OF THE
PRECIPITATION (EVEN THOUGH RAP ANALYSIS OF MUCAPE AND MID-LEVEL
LAPSE RATE VALUES ARE VERY WEAK)...HAVE EXTENDED THE SLIGHT
CHANCE OF THUNDER A LITTLE LONGER OVER THE EAST THIS MORNING TO
COINCIDE WITH THE AXIS OF MOISTURE AND LATEST THUNDER
AREAS.
BEHIND THE COLD FRONT...MAY SEE A FEW PEAKS OF SUNSHINE OVER THE
CENTRAL/EAST (WHERE FOG ISN/T OCCURRING) AS THIS MID LEVEL DRY SLOT
MOVES THROUGH AND BEFORE THE NEXT WAVE OF LOW LEVEL MOISTURE AND
PRECIPITATION (CURRENTLY IN THE EASTERN DAKOTAS AND WESTERN
MINNESOTA) MOVES OVER THE AREA. WILL CONTINUE THE IDEA SHOWN IN THE
PREVIOUS FORECAST OF ISOLATED TO SCATTERED SHOWERS MOVING OVER THE
WEST OR NORTHWEST HALF OF THE CWA LATER THIS AFTERNOON AND
CONTINUING THROUGH A GOOD PORTION OF THE NIGHT TONIGHT (ESPECIALLY
THE KEWEENAW TONIGHT). QPF AMOUNTS WILL BE MUCH LIGHTER THAN SEEN
OVER THE LAST COUPLE DAYS AND MAINLY BETWEEN A TRACE AND A COUPLE
TENTHS. IN ADDITION...IT WILL BECOME BREEZY BEHIND THE COLD
FRONT...WITH BUFKIT SOUNDINGS INDICATING GUSTS AROUND 25KTS OVER
MUCH MUCH OF UPPER MICHIGAN TODAY. WITH THE COLD AIR ADVECTION IN
PLACE THROUGH MUCH OF TONIGHT...THOSE GUSTS WILL LIKELY KEEP UP AS
WINDS SHIFT TO THE WEST THROUGH THE NIGHT. WHILE THE KEWEENAW MAY BE
PROTECTED SLIGHTLY TODAY...THE WINDS SHOULD REALLY KICK IN TONIGHT
AS IT IS CLOSEST TO THE TIGHTEST PRESSURE GRADIENT WITH THE
DEPARTING LOW AND RESULTING STRONGER WINDS JUST ABOVE THE SURFACE.
EXPECT THERE TO BE A PERIOD THIS EVENING AND INTO THE EARLY
OVERNIGHT HOURS WHERE GUSTS IN THE KEWEENAW WILL BE BETWEEN
30-35KTS.
FINALLY FOR TEMPERATURES...VALUES THIS MORNING HAVE BEEN CONSISTENT
IN THE 50S OVER THE INTERIOR LOCATIONS...ALTHOUGH LOCATIONS NEAR
THE COOLING OF THE GREAT LAKES HAVE BEEN BOUNCING UP AND DOWN
DEPENDING ON THE WIND DIRECTION. WITH THE WARM START AND THE WARM
FRONT PUSHING NORTHEAST THROUGH MUCH OF UPPER MICHIGAN
TODAY...SHOULD SEE TEMPERATURES RISE INTO THE MID-UPPER 60S OVER
THE CENTRAL/EASTERN CWA AND WHERE SOME SUNSHINE OCCURS WILL
PROBABLY SEE SOME SITES HITTING THE 70 DEGREE MARK. COLDER AIR
ARRIVING BEHIND THE COLD FRONT WILL LEAD TO FALLING TEMPS OVER THE
WEST IN THE AFTERNOON AND THE REST OF THE AREA TOWARDS EVENING. THE
CLOUD COVER TONIGHT WILL KEEP TEMPS A LITTLE ABOVE NORMAL AND HAVE
LOWS IN THE LOWER 40S.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 431 PM EDT THU MAY 8 2014
A SOMEWHAT PROGRESSIVE PATTERN IN THE LONG TERM WILL KEEP THE
OVERALL PERIOD DAMP WITH TEMPS AROUND AVERAGE THIS WEEKEND AND
SLIGHTLY BELOW AVERAGE NEXT WEEK.
A WEAK BLOCKING SETUP OVER THE CENTRAL CONUS TODAY WILL BEGIN
BREAKING DOWN OVERNIGHT AS A STRONG SHORTWAVE TROUGH EJECTS
NORTHEASTWARD OUT OF THE CENTRAL PLAINS. THIS TROUGH WILL PUSH
EASTWARD INTO A SHARP RIDGE EXTENDING NORTHWARD OVER HUDSON BAY.
DEEP TROUGHING DEVELOPING OVER THE GULF OF ALASKA TODAY WILL THEN
TRACK TO THE SOUTHERN ROCKIES BY SUNDAY NIGHT AND SETUP A PATTERN
FAIRLY SIMILAR TO THE PAST COUPLE DAYS...WITH DEEP TROUGHING OVER
CENTRAL NORTH AMERICA AND A RIDGE BUILDING ACROSS THE EASTERN CONUS.
THE TROUGH WILL SHIFT NORTHEASTWARD EARLY NEXT WEEK...WITH BROAD
TROUGHING DEVELOPING OVER THE GREAT LAKES REGION BY MID-WEEK.
FRIDAY NIGHT...THE TROUGH AXIS APPROACHING THE AREA TODAY WILL CROSS
OVER THE CWA BETWEEN 15 AND 21Z FRIDAY. HOWEVER...A REINFORCING
TROUGH ROTATING AROUND A CLOSED MID-LEVEL LOW OVER NORTHERN
SASKATCHEWAN WILL TRACK IN BEHIND THIS LEADING TROUGH AXIS AND
CONTINUE CHANCES FOR PRECIP THROUGH MUCH OF FRIDAY NIGHT. MOISTURE
AVAILABILITY LESSENS BY THIS TIME...SO DO NOT EXPECT ANYTHING MORE
THAN SOME SCATTERED LIGHT SHOWERS SHIFTING FROM WEST TO EAST FRIDAY
NIGHT.
SATURDAY LOOKS TO BE THE ONLY TRUE DRY DAY IN THE EXTENDED FORECAST
WITH A WEAK MID-LEVEL RIDGE BUILDING ACROSS THE UPPER MS VALLEY. A
PUSH OF 0 TO 2C H8 TEMPS BEHIND FRIDAYS SYSTEM WILL LEAD TO A COOLER
DAY THAN FRIDAY...BUT SUBSTANTIAL DRY AIR THROUGH THE COLUMN WILL
RESULT IN MOSTLY SUNNY SKIES WITH SOME AFTERNOON CUMULUS AWAY FROM
THE GREAT LAKES. HIGHS SHOULD MAKE IT TO THE LOW 60S INLAND...BUT
STRUGGLE TO REACH 50 VERY NEAR SHORELINE LOCATIONS DOWNWIND OF LAKE
SUPERIOR WITH WESTERLY FLOW. AS FOR FIRE WX CONCERNS...TEMPS WILL BE
AT OR SLIGHTLY ABOVE AVERAGE WITH MIN RH VALUES IN THE MID 20S TO
LOW 30S ACROSS MUCH OF THE INTERIOR...AND WINDS GUSTING TO AROUND
20MPH.
SATURDAY NIGHT AND SUNDAY...A DECAYING TROUGH AXIS ENTERING THE
RIDGE OVER A WEAK SFC WARM FRONT TRACKING IN FROM THE SW WILL YIELD
SOME SCATTERED RAIN SHOWERS ACROSS MAINLY THE WESTERN AND CENTRAL
CWA. THIS WILL KEEP SKIES MOSTLY CLOUDY THROUGH SUNDAY. THE FRONT
LOOKS TO STALL ALONG LAKE SUPERIOR...SO QUITE A CONTRAST IN TEMPS
WILL BE POSSIBLE AS THE KEWEENAW AND EASTERN CWA REMAIN IN THE UPPER
40S TO MID 50S IN SE FLOW WHILE THE INTERIOR WEST SEES TEMPS IN THE
MID TO UPPER 60S UNDER WITH SW FLOW.
SUNDAY NIGHT THROUGH TUESDAY...THE DEVELOPING TROUGH ACROSS THE
PLAINS WILL BEGIN SHIFTING EASTWARD ACROSS THE MID AND UPPER MS
VALLEY SUNDAY NIGHT. THIS WILL BRING SCATTERED TO NUMEROUS SHOWERS
AND SOME EMBEDDED THUNDERSTORMS ACROSS THE AREA. HOWEVER...TIMING
AND OVERALL COVERAGE IS STILL IN QUESTION AS THE GFS IS SOMEWHAT
MORE PROGRESSIVE WITH THE TROUGH COMPARED TO THE ECMWF AND THE GEM.
WITH THAT SAID...THE BEST CHANCE FOR INCREASED COVERAGE AND HEAVIER
SHOWERS/STORMS SHOULD BE MONDAY AFTERNOON THROUGH TUESDAY.
WEDNESDAY AND THURSDAY...PERSISTENT CYCLONIC FLOW WILL CONTINUE OVER
THE REGION AS THE TROUGH STALLS OVER HUDSON BAY AND NORTHERN
ONTARIO. WITH N TO NW FLOW...CLOUD COVER...AND H8 TEMPS OF -4 TO
-8C...TEMPS WILL STRUGGLE TO GET OUT OF THE 40S ACROSS THE NORTH
HALF AND THE LOW 50S FOR THE SOUTH HALF.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 128 AM EDT FRI MAY 9 2014
SHOWERS AND SCT TSRA WILL LIFT TO THE NE THROUGH UPPER MICHIGAN
OVERNIGHT. AS A RESULT...LOW LEVEL MOISTENING FROM THE RAIN AND S TO
SE FLOW WILL KEEP OR DROP CIGS INTO THE IFR/LIFR RANGE TONIGHT.
CONDITIONS WILL IMPROVE FRI MORNING AS WINDS BECOME SW AND GREATER
DRYING/MIXING MOVES IN. A BRIEF PERIOD OF VFR CONDITIONS MAY DEVELOP
BY AFTERNOON BUT LOWER MVFR CIGS ARE EXPECTED TO REDEVELOP OVER THE
WEST AS ADDITIONAL MOISTURE WRAPS AROUND THE DEPARTING LOW PRESSURE
SYSTEM.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 422 AM EDT FRI MAY 9 2014
A LOW PRESSURE SYSTEM NEAR DULUTH EARLY THIS MORNING WILL SLIDE
NORTHEAST INTO ONTARIO TODAY. AS THIS OCCURS...WINDS WILL SHIFT
AROUND TO THE SOUTHWESTERLY DIRECTION TODAY AND THEN TO THE WEST
TONIGHT. EXPECT THE WINDS TO INCREASE FROM WEST TO EAST TODAY AND
GENERALLY TO 25KTS TONIGHT...ALTHOUGH THERE COULD BE SOME GUSTS
TO 30KTS OVER THE CENTRAL LAKE. THESE STRONGER WINDS...COMBINED WITH
GRADUALLY DRYING LOWER LEVELS SHOULD LEAD TO A DIMINISHMENT OF THE
DENSE FOG OVER LAKE SUPERIOR FROM SOUTHWEST TO NORTHEAST TODAY.
OPTED TO EXTENDED THE DENSE FOG ADVISORY FOR LAKE SUPERIOR INTO THE
AFTERNOON HOURS TO BETTER MATCH UP WITH THE INCREASING WINDS AND
DRIER AIR. A HIGH PRESSURE RIDGE WILL THEN SLIDE OVER THE AREA ON
SATURDAY AND LEAD TO WINDS FALLING BELOW 15KTS SATURDAY NIGHT. THESE
LIGHT WINDS WILL REMAIN THROUGH SUNDAY EVENING. A LOW PRESSURE
SYSTEM MOVING TOWARDS THE UPPER GREAT LAKES REGION FROM THE CENTRAL
PLAINS ON SUNDAY NIGHT WILL LEAD TO INCREASING EASTERLY WINDS (TO
25KTS BY MONDAY EVENING). THEN AS THE LOW SHIFTS NORTHEAST INTO
ONTARIO ON TUESDAY...WINDS WILL SHIFT TO THE SOUTHWEST AND STAY
BELOW 20KTS.
&&
.HYDROLOGY...
ISSUED AT 456 AM EDT FRI MAY 9 2014
THE RAIN SHOWERS AND THUNDERSTORMS PRODUCING HEAVY RAIN HAVE
NEARLY DEPARTED UPPER MICHIGAN EARLY THIS MORNING. BUT THEY HAVE
LEFT RISING RIVER LEVELS IN THEIR WAKE...ESPECIALLY OVER WESTERN
UPPER MICHIGAN WHERE THE HEAVIEST RAIN HAS FALLEN. THE KEWEENAW
PENINSULA HAS SEEN AROUND 0.75 INCHES OVERNIGHT IN ADDITION TO THE
INCH OF RAIN THAT FELL LAST NIGHT. THIS AS LED TO ANOTHER RISE OF
THE TRAP ROCK RIVER OVER THE LAST COUPLE OF HOURS. IT HAS LEVELED
OUT SOMEWHAT OVER THE LAST HOUR...BUT WITH A COUPLE HOURS LEFT
OF RAIN AND SNOW MELT CONTINUING WOULD EXPECT A LITTLE MORE RISE
THIS MORNING. IT DID BRIEFLY REACH 10.15FT...WHICH PUTS THE CURRENT
CREST AT THE 4TH HIGHEST ON RECORD.
WARM TEMPERATURES TODAY WILL CONTINUE THE MELTING FROM A FEW INCHES
OF SNOW WATER EQUIVALENT SHOWN FROM NOHRSC MODEL FROM THE
TIP OF THE KEWEENAW PENINSULA THROUGH PAINESDALE...DONKEN...AND
WINONA. THIS LINES UP WELL WITH THE LATEST SNOW DEPTHS REPORTED AT
PAINESDALE AND HERMAN. WILL SEE HOW THIS SNOW MELT /WARMER FCST
TEMPS FOR THE REST OF THIS WEEK/ IMPACT DOWNSTREAM RIVERS INCLUDING
THE STURGEON RIVER OF BARAGA/HOUGHTON COUNTIES AND THE TRAP ROCK
RIVER. MOST IF NOT ALL OF THE SNOW COULD MELT BY THIS
WEEKEND...BUT IT WILL KEEP THE RIVER LEVELS HIGH INTO EARLY NEXT
WEEK. IN ADDITION...WIDESPREAD RAIN IS EXPECTED AGAIN ON
MONDAY AND THE CURRENT FORECAST CALLS FOR AROUND A HALF AN INCH
OF ACCUMULATION. THOSE LIVING AROUND RIVERS...CREEKS...AND STREAMS
SHOULD CONTINUE TO MONITOR RIVER LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 5 PM EDT /4 PM CDT/ THIS AFTERNOON FOR
LSZ162-240>251-263>267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...KLUBER
AVIATION...JLB
MARINE...SRF
HYDROLOGY...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
445 AM EDT FRI MAY 9 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 444 AM EDT FRI MAY 9 2014
THE UPPER TROUGH THAT HAS BEEN CONTROLLING OUR WEATHER FOR THE LAST
COUPLE OF DAYS IS CURRENTLY MOVING NORTHEAST THROUGH THE CENTRAL
PLAINS. MOISTURE LADEN AIR STREAMING NORTHEAST AHEAD OF THIS TROUGH
CAN BE SEEN ON WV IMAGERY EARLY THIS MORNING...WHICH IS HELPING TO
FUEL SHOWERS AND ISOLATED THUNDERSTORMS FROM WESTERN LAKE SUPERIOR
THROUGH PORTIONS OF UPPER MICHIGAN...AND SOUTHEAST TO EASTERN
WISCONSIN. AT THE SURFACE...A 998MB LOW IS LOCATED JUST SOUTHWEST OF
DULUTH AND A WARM FRONT STRETCHES EAST ALONG THE U.P. AND
WISCONSIN BORDER. SHORTWAVES EMBEDDED WITHIN THE WARM MOIST
SOUTHWESTERLY FLOW CONTINUES TO PRODUCE AREAS OF THUNDERSTORMS OVER
THE WESTERN HALF OF THE GREAT LAKES REGION AND EXPECT THAT TO
CONTINUE FOR AREAS WITHIN THE WARM/MOIST AIRMASS.
AS THE LOW LIFTS NORTHEAST TODAY...THE COLD FRONT (CURRENTLY
STRETCHING SOUTH FROM SOUTHEAST MINNESOTA THROUGH NORTHERN
MISSOURI) WILL SWEEP NORTHEAST ACROSS THE UPPER GREAT LAKES REGION.
WITH THE SHOWER/THUNDERSTORM COVERAGE STARTING TO BECOME MORE
SCATTERED/ISOLATED...WILL FOLLOW THAT IDEA FOR POPS AHEAD OF THE
COLD FRONT. ALREADY STARTING TO SEE THE AFFECT OF THE DRYING ALOFT
OVER NORTHWEST WISCONSIN AND EXPECT THE LAST AREAS OF SHOWERS FOR
THIS MORNING TO PUSH THROUGH WESTERN UPPER MICHIGAN OVER THE NEXT
COUPLE OF HOURS. AS THAT DRYING SHIFTS EAST THIS MORNING...WILL
DIMINISH POPS FROM WEST TO EAST DURING THE MORNING HOURS. WITH
THERE STILL BEING SOME ISOLATED THUNDER ON THE BACK EDGE OF THE
PRECIPITATION (EVEN THOUGH RAP ANALYSIS OF MUCAPE AND MID-LEVEL
LAPSE RATE VALUES ARE VERY WEAK)...HAVE EXTENDED THE SLIGHT
CHANCE OF THUNDER A LITTLE LONGER OVER THE EAST THIS MORNING TO
COINCIDE WITH THE AXIS OF MOISTURE AND LATEST THUNDER
AREAS.
BEHIND THE COLD FRONT...MAY SEE A FEW PEAKS OF SUNSHINE OVER THE
CENTRAL/EAST (WHERE FOG ISN/T OCCURRING) AS THIS MID LEVEL DRY SLOT
MOVES THROUGH AND BEFORE THE NEXT WAVE OF LOW LEVEL MOISTURE AND
PRECIPITATION (CURRENTLY IN THE EASTERN DAKOTAS AND WESTERN
MINNESOTA) MOVES OVER THE AREA. WILL CONTINUE THE IDEA SHOWN IN THE
PREVIOUS FORECAST OF ISOLATED TO SCATTERED SHOWERS MOVING OVER THE
WEST OR NORTHWEST HALF OF THE CWA LATER THIS AFTERNOON AND
CONTINUING THROUGH A GOOD PORTION OF THE NIGHT TONIGHT (ESPECIALLY
THE KEWEENAW TONIGHT). QPF AMOUNTS WILL BE MUCH LIGHTER THAN SEEN
OVER THE LAST COUPLE DAYS AND MAINLY BETWEEN A TRACE AND A COUPLE
TENTHS. IN ADDITION...IT WILL BECOME BREEZY BEHIND THE COLD
FRONT...WITH BUFKIT SOUNDINGS INDICATING GUSTS AROUND 25KTS OVER
MUCH MUCH OF UPPER MICHIGAN TODAY. WITH THE COLD AIR ADVECTION IN
PLACE THROUGH MUCH OF TONIGHT...THOSE GUSTS WILL LIKELY KEEP UP AS
WINDS SHIFT TO THE WEST THROUGH THE NIGHT. WHILE THE KEWEENAW MAY BE
PROTECTED SLIGHTLY TODAY...THE WINDS SHOULD REALLY KICK IN TONIGHT
AS IT IS CLOSEST TO THE TIGHTEST PRESSURE GRADIENT WITH THE
DEPARTING LOW AND RESULTING STRONGER WINDS JUST ABOVE THE SURFACE.
EXPECT THERE TO BE A PERIOD THIS EVENING AND INTO THE EARLY
OVERNIGHT HOURS WHERE GUSTS IN THE KEWEENAW WILL BE BETWEEN
30-35KTS.
FINALLY FOR TEMPERATURES...VALUES THIS MORNING HAVE BEEN CONSISTENT
IN THE 50S OVER THE INTERIOR LOCATIONS...ALTHOUGH LOCATIONS NEAR
THE COOLING OF THE GREAT LAKES HAVE BEEN BOUNCING UP AND DOWN
DEPENDING ON THE WIND DIRECTION. WITH THE WARM START AND THE WARM
FRONT PUSHING NORTHEAST THROUGH MUCH OF UPPER MICHIGAN
TODAY...SHOULD SEE TEMPERATURES RISE INTO THE MID-UPPER 60S OVER
THE CENTRAL/EASTERN CWA AND WHERE SOME SUNSHINE OCCURS WILL
PROBABLY SEE SOME SITES HITTING THE 70 DEGREE MARK. COLDER AIR
ARRIVING BEHIND THE COLD FRONT WILL LEAD TO FALLING TEMPS OVER THE
WEST IN THE AFTERNOON AND THE REST OF THE AREA TOWARDS EVENING. THE
CLOUD COVER TONIGHT WILL KEEP TEMPS A LITTLE ABOVE NORMAL AND HAVE
LOWS IN THE LOWER 40S.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 431 PM EDT THU MAY 8 2014
A SOMEWHAT PROGRESSIVE PATTERN IN THE LONG TERM WILL KEEP THE
OVERALL PERIOD DAMP WITH TEMPS AROUND AVERAGE THIS WEEKEND AND
SLIGHTLY BELOW AVERAGE NEXT WEEK.
A WEAK BLOCKING SETUP OVER THE CENTRAL CONUS TODAY WILL BEGIN
BREAKING DOWN OVERNIGHT AS A STRONG SHORTWAVE TROUGH EJECTS
NORTHEASTWARD OUT OF THE CENTRAL PLAINS. THIS TROUGH WILL PUSH
EASTWARD INTO A SHARP RIDGE EXTENDING NORTHWARD OVER HUDSON BAY.
DEEP TROUGHING DEVELOPING OVER THE GULF OF ALASKA TODAY WILL THEN
TRACK TO THE SOUTHERN ROCKIES BY SUNDAY NIGHT AND SETUP A PATTERN
FAIRLY SIMILAR TO THE PAST COUPLE DAYS...WITH DEEP TROUGHING OVER
CENTRAL NORTH AMERICA AND A RIDGE BUILDING ACROSS THE EASTERN CONUS.
THE TROUGH WILL SHIFT NORTHEASTWARD EARLY NEXT WEEK...WITH BROAD
TROUGHING DEVELOPING OVER THE GREAT LAKES REGION BY MID-WEEK.
FRIDAY NIGHT...THE TROUGH AXIS APPROACHING THE AREA TODAY WILL CROSS
OVER THE CWA BETWEEN 15 AND 21Z FRIDAY. HOWEVER...A REINFORCING
TROUGH ROTATING AROUND A CLOSED MID-LEVEL LOW OVER NORTHERN
SASKATCHEWAN WILL TRACK IN BEHIND THIS LEADING TROUGH AXIS AND
CONTINUE CHANCES FOR PRECIP THROUGH MUCH OF FRIDAY NIGHT. MOISTURE
AVAILABILITY LESSENS BY THIS TIME...SO DO NOT EXPECT ANYTHING MORE
THAN SOME SCATTERED LIGHT SHOWERS SHIFTING FROM WEST TO EAST FRIDAY
NIGHT.
SATURDAY LOOKS TO BE THE ONLY TRUE DRY DAY IN THE EXTENDED FORECAST
WITH A WEAK MID-LEVEL RIDGE BUILDING ACROSS THE UPPER MS VALLEY. A
PUSH OF 0 TO 2C H8 TEMPS BEHIND FRIDAYS SYSTEM WILL LEAD TO A COOLER
DAY THAN FRIDAY...BUT SUBSTANTIAL DRY AIR THROUGH THE COLUMN WILL
RESULT IN MOSTLY SUNNY SKIES WITH SOME AFTERNOON CUMULUS AWAY FROM
THE GREAT LAKES. HIGHS SHOULD MAKE IT TO THE LOW 60S INLAND...BUT
STRUGGLE TO REACH 50 VERY NEAR SHORELINE LOCATIONS DOWNWIND OF LAKE
SUPERIOR WITH WESTERLY FLOW. AS FOR FIRE WX CONCERNS...TEMPS WILL BE
AT OR SLIGHTLY ABOVE AVERAGE WITH MIN RH VALUES IN THE MID 20S TO
LOW 30S ACROSS MUCH OF THE INTERIOR...AND WINDS GUSTING TO AROUND
20MPH.
SATURDAY NIGHT AND SUNDAY...A DECAYING TROUGH AXIS ENTERING THE
RIDGE OVER A WEAK SFC WARM FRONT TRACKING IN FROM THE SW WILL YIELD
SOME SCATTERED RAIN SHOWERS ACROSS MAINLY THE WESTERN AND CENTRAL
CWA. THIS WILL KEEP SKIES MOSTLY CLOUDY THROUGH SUNDAY. THE FRONT
LOOKS TO STALL ALONG LAKE SUPERIOR...SO QUITE A CONTRAST IN TEMPS
WILL BE POSSIBLE AS THE KEWEENAW AND EASTERN CWA REMAIN IN THE UPPER
40S TO MID 50S IN SE FLOW WHILE THE INTERIOR WEST SEES TEMPS IN THE
MID TO UPPER 60S UNDER WITH SW FLOW.
SUNDAY NIGHT THROUGH TUESDAY...THE DEVELOPING TROUGH ACROSS THE
PLAINS WILL BEGIN SHIFTING EASTWARD ACROSS THE MID AND UPPER MS
VALLEY SUNDAY NIGHT. THIS WILL BRING SCATTERED TO NUMEROUS SHOWERS
AND SOME EMBEDDED THUNDERSTORMS ACROSS THE AREA. HOWEVER...TIMING
AND OVERALL COVERAGE IS STILL IN QUESTION AS THE GFS IS SOMEWHAT
MORE PROGRESSIVE WITH THE TROUGH COMPARED TO THE ECMWF AND THE GEM.
WITH THAT SAID...THE BEST CHANCE FOR INCREASED COVERAGE AND HEAVIER
SHOWERS/STORMS SHOULD BE MONDAY AFTERNOON THROUGH TUESDAY.
WEDNESDAY AND THURSDAY...PERSISTENT CYCLONIC FLOW WILL CONTINUE OVER
THE REGION AS THE TROUGH STALLS OVER HUDSON BAY AND NORTHERN
ONTARIO. WITH N TO NW FLOW...CLOUD COVER...AND H8 TEMPS OF -4 TO
-8C...TEMPS WILL STRUGGLE TO GET OUT OF THE 40S ACROSS THE NORTH
HALF AND THE LOW 50S FOR THE SOUTH HALF.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 128 AM EDT FRI MAY 9 2014
SHOWERS AND SCT TSRA WILL LIFT TO THE NE THROUGH UPPER MICHIGAN
OVERNIGHT. AS A RESULT...LOW LEVEL MOISTENING FROM THE RAIN AND S TO
SE FLOW WILL KEEP OR DROP CIGS INTO THE IFR/LIFR RANGE TONIGHT.
CONDITIONS WILL IMPROVE FRI MORNING AS WINDS BECOME SW AND GREATER
DRYING/MIXING MOVES IN. A BRIEF PERIOD OF VFR CONDITIONS MAY DEVELOP
BY AFTERNOON BUT LOWER MVFR CIGS ARE EXPECTED TO REDEVELOP OVER THE
WEST AS ADDITIONAL MOISTURE WRAPS AROUND THE DEPARTING LOW PRESSURE
SYSTEM.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 422 AM EDT FRI MAY 9 2014
A LOW PRESSURE SYSTEM NEAR DULUTH EARLY THIS MORNING WILL SLIDE
NORTHEAST INTO ONTARIO TODAY. AS THIS OCCURS...WINDS WILL SHIFT
AROUND TO THE SOUTHWESTERLY DIRECTION TODAY AND THEN TO THE WEST
TONIGHT. EXPECT THE WINDS TO INCREASE FROM WEST TO EAST TODAY AND
GENERALLY TO 25KTS TONIGHT...ALTHOUGH THERE COULD BE SOME GUSTS
TO 30KTS OVER THE CENTRAL LAKE. THESE STRONGER WINDS...COMBINED WITH
GRADUALLY DRYING LOWER LEVELS SHOULD LEAD TO A DIMINISHMENT OF THE
DENSE FOG OVER LAKE SUPERIOR FROM SOUTHWEST TO NORTHEAST TODAY.
OPTED TO EXTENDED THE DENSE FOG ADVISORY FOR LAKE SUPERIOR INTO THE
AFTERNOON HOURS TO BETTER MATCH UP WITH THE INCREASING WINDS AND
DRIER AIR. A HIGH PRESSURE RIDGE WILL THEN SLIDE OVER THE AREA ON
SATURDAY AND LEAD TO WINDS FALLING BELOW 15KTS SATURDAY NIGHT. THESE
LIGHT WINDS WILL REMAIN THROUGH SUNDAY EVENING. A LOW PRESSURE
SYSTEM MOVING TOWARDS THE UPPER GREAT LAKES REGION FROM THE CENTRAL
PLAINS ON SUNDAY NIGHT WILL LEAD TO INCREASING EASTERLY WINDS (TO
25KTS BY MONDAY EVENING). THEN AS THE LOW SHIFTS NORTHEAST INTO
ONTARIO ON TUESDAY...WINDS WILL SHIFT TO THE SOUTHWEST AND STAY
BELOW 20KTS.
&&
.HYDROLOGY...
ISSUED AT 431 PM EDT THU MAY 8 2014
WET WEATHER WILL RETURN INTO FRIDAY NIGHT...THEN RETURN AGAIN BY
EARLY NEXT WEEK. MOST OF THE RAIN LOOKS TO FALL OVER THE STURGEON
RIVER BASIN THIS EVENING. ADDING TO THIS WILL BE SOME MELTING FROM A
FEW INCHES OF SNOW WATER EQUIVALENT SHOWN FROM NOHRSC MODEL FROM THE
TIP OF THE KEWEENAW PENINSULA THROUGH PAINESDALE...DONKEN...AND
WINONA. THIS LINES UP WELL WITH THE LATEST SNOW DEPTHS REPORTED AT
PAINESDALE AND HERMAN. WILL SEE HOW THIS SNOW MELT /WARMER FCST
TEMPS FOR THE REST OF THIS WEEK/ IMPACT DOWNSTREAM RIVERS INCLUDING
THE STURGEON RIVER OF BARAGA/HOUGHTON COUNTIES AND THE TRAP ROCK
RIVER. MOST IF NOT ALL OF THE SNOW COULD MELT BY THIS WEEKEND.
SEVERAL ROUNDS OF SHOWERS AND THUNDERSTORMS WILL AFFECT THE AREA
INTO EARLY FRIDAY. RAINFALL AMOUNTS WILL LIKELY EXCEED A HALF OF AN
INCH FOR MUCH OF WESTERN UPPER MICHIGAN...AND LOCALIZED AMOUNTS OVER
AN INCH SHOULD OCCUR WHERE THUNDERSTORMS TRACK. THIS WILL KEEP THE
RIVER LEVELS HIGH INTO EARLY NEXT WEEK. THOSE LIVING AROUND
RIVERS...CREEKS...AND STREAMS SHOULD CONTINUE TO MONITOR RIVER
LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
DENSE FOG ADVISORY UNTIL 5 PM EDT /4 PM CDT/ THIS AFTERNOON FOR
LSZ162-240>251-263>267.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...SRF
LONG TERM...KLUBER
AVIATION...JLB
MARINE...SRF
HYDROLOGY...KLUBER
AREA FORECAST DISCUSSION...UPDATED
NWS TWIN CITIES/CHANHASSEN MN
1057 PM CDT SAT MAY 10 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 235 PM CDT SAT MAY 10 2014
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS ARE EXPECTED TO MOVE
ACROSS THE FORECAST AREA THROUGH MIDNIGHT. THE THREAT FOR SEVERE
WEATHER IS LOW...AND THE BEST CHANCE FOR HAIL AND WIND EXISTS ACROSS
WEST CENTRAL AND SOUTHWEST MINNESOTA.
WEAK SURFACE LOW NEARLY CO-LOCATED WITH NICE SHORTWAVE DIGGING IN
ACROSS SOUTH DAKOTA THIS AFTERNOON. THE COMBINATION OF SURFACE
HEATING...WEAK MOISTURE TRANSPORT AND LIFT IS PROMOTING CONVECTIVE
INITIATION ACROSS SOUTHWEST MINNESOTA AND NORTHERN IOWA. THE CURRENT
SHOWERS EXTEND ALONG A NW-SE AXIS OF HIGHER PWATS /0.70"-0.90"/ PER
THE 19Z SURFACE RAP ANALYSIS. THE SBCAPE IS WEAK BUT THE APPROACH
SHORTWAVE IS HELPING TO STEEPEN THE MID LEVEL LAPSE RATE TO
7-7.5C/KM IN WESTERN MINNESOTA. THE UPPER FLOW IS PRETTY WEAK BUT
THERE SHOULD BE ENOUGH FORCING AND SHEAR TO PROMOTE MULTI-CELL
CONVECTIVE MODE AND A SLIGHT CHANCE FOR HAIL AND GUSTY WINDS WITH
THE STRONGEST UPDRAFTS. THIS IS ESPECIALLY TRUE FROM 4-7PM WHERE
THE SFC-6KM MAX LAYER THETA-E DIFFERENCE IS BETWEEN -15C AND -20C
IN WESTERN MN. FARTHER EAST IN EASTERN MN AND WESTERN WI...THE
CONVECTIVE POTENTIAL IS LOWER /ALTHOUGH THERE SHOULD STILL BE A
HEALTHY BAND OF SHOWERS WITH GOOD VERTICAL EXTENT AND IN-CLOUD
LIGHTNING/. MANY OF THE HI-RES WRF SIMULATIONS
/SPC...HOPWRF...NCEP/ HAVE THE RAIN CLEARING MN BY ABOUT 9PM AND
WESTERN WI BY ABOUT MIDNIGHT. THERE WILL BE A BREAK IN THE PRECIP
BEFORE ISENTROPIC LIFT WITH THE STRENGTHENING SOUTHERN PLAINS LOW
STARTS TO SPREAD SHOWERS AND STORMS INTO SOUTHERN MINNESOTA BY
TOMORROW AFTERNOON.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 235 PM CDT SAT MAY 10 2014
THE LONG TERM PORTION OF THE FORECAST WILL BE ACTIVE FROM THE GET-
GO...WITH A SURFACE TROUGH EXPECTED TO BE NOSING INTO SOUTHERN MN
AT 00Z MONDAY. THUNDERSTORMS /LIKELY SEVERE/ ARE EXPECTED TO BE
ONGOING TO THE SOUTH...WITH THE THREAT FOR STRONG THUNDERSTORMS
SHIFTING NORTH INTO SOUTH CENTRAL/EAST MN AND WEST CENTRAL WI ON
SUNDAY NIGHT AS THE INSTABILITY GRADIENT LIFTS NORTH. PRECIPITABLE
WATER VALUES INCREASE TO AROUND 200 PERCENT OF NORMAL /1.5
INCHES/...SO HEAVY RAIN PRODUCING THUNDERSTORMS ARE CERTAINLY A
POSSIBILITY AS LLVL MOISTURE TRANSPORT ENSUES SUNDAY NIGHT AND
MONDAY. COULD STILL POTENTIALLY SEE AMOUNTS CURTAILED A BIT DUE
TO THE CONVECTION TO THE SOUTH...BUT STILL THINK 1-2 INCH TOTALS
ARE QUITE POSSIBLE BETWEEN SUNDAY EVENING AND MONDAY MORNING ALONG
THE INTERSTATE 90 CORRIDOR OF SOUTH CENTRAL AND SOUTHEAST MN...AND
EAST OF INTERSTATE 35 FROM THE TWIN CITIES ACROSS WEST CENTRAL WI.
MONDAY AFTERNOON/EVE WILL BE ANOTHER WINDOW OF TIME WHEN STRONG TO
SEVERE STORMS COULD SKIRT THE SOUTHEASTERN BORDER OF THE FORECAST
AREA...NAMELY ACROSS WEST CENTRAL WI. MONDAY NIGHT AND TUESDAY THE
MID LEVEL TROUGH PIVOTS ACROSS THE AREA AND SUPPLIES ANOTHER ROUND
OF SHOWERS...ALTHOUGH THE THUNDER POTENTIAL WILL HAVE LOWERED
NOTABLY AND COVERAGE SHOULD BE MORE SCATTERED IN NATURE.
MODEL TRENDS FOR WEDNESDAY...PARTICULARLY THE 10.12Z ECMWF WERE TO
KEEP THE NORTHERN AND SOUTHERN STREAM ENERGY A BIT MORE
DISJOINTED...HENCE LEAVING THE LOCAL AREA IN BETWEEN THE MAIN
AREAS OF FORCING. HOWEVER...COULD STILL SEE A FEW INSTABILITY
SHOWERS ON WEDNESDAY THROUGH THE END OF THE WEEK AS THE NORTHERN
STREAM TROUGH SAGS INTO THE UPPER MIDWEST AND GREAT LAKES REGION.
NO SURPRISE THAT TEMPERATURES WILL BE COOL NEXT WEEK...AS H85
TEMPERATURES FLIRT WITH 0 CELSIUS FROM TUESDAY THROUGH FRIDAY.
WILL NEED TO MONITOR THE POTENTIAL FOR FROST DURING THE OVERNIGHT
PERIODS...WITH THE GROWING SEASON NEARING.
BETTER NEWS /IN THE FORM OF WARMER TEMPERATURES/ IS EXPECTED TO
ARRIVE FOR NEXT WEEKEND...AS THE TROUGH LIFTS TO HUDSON BAY AND
WESTERN RIDGING BUILDS TOWARD THE CENTRAL CONUS. EXPECT TO SEE 60S
BACK IN THE FORECAST FOR NEXT SATURDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1053 PM CDT SAT MAY 10 2014
VFR CONDITIONS EXPECTED THROUGH MOST OF SUNDAY AFTERNOON. LIGHT
SHOWERS ARE DISSIPATING AND PUSHING EAST INTO WESTERN WISCONSIN
LATE THIS EVENING. CLEARING SKIES TONIGHT WILL GIVE WAY TO
THICKENING AND LOWERING CLOUDS SUNDAY...WITH SHOWERS AND
THUNDERSTORMS LIFTING NORTH FROM THE MISSOURI VALLEY SUNDAY
EVENING. CONDITIONS WILL DETERIORATE TO MVFR AND POSSIBLY IFR
LEVELS AT TIMES...PARTICULARLY IN ANY THUNDERSTORM. HEAVY RAINFALL
IS POSSIBLE TOWARD THE END OF THE TAF PERIOD.
KMSP...NO ADDITIONAL CONCERNS FROM THE OVERVIEW SECTION.
/OUTLOOK FOR KMSP/
MON...MVFR LIKELY. IFR POSSIBLE. -SHRA LIKELY. WINDS NW 10KTS.
TUE...MVFR POSSIBLE. ISO-SCT -SHRA. WINDS W-NW 15-20KTS.
WED...VFR. WINDS W-NW 10-15 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...CLF
LONG TERM...LS
AVIATION...BORGHOFF
AREA FORECAST DISCUSSION...UPDATED
NWS TWIN CITIES/CHANHASSEN MN
714 PM CDT SAT MAY 10 2014
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 235 PM CDT SAT MAY 10 2014
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS ARE EXPECTED TO MOVE
ACROSS THE FORECAST AREA THROUGH MIDNIGHT. THE THREAT FOR SEVERE
WEATHER IS LOW...AND THE BEST CHANCE FOR HAIL AND WIND EXISTS ACROSS
WEST CENTRAL AND SOUTHWEST MINNESOTA.
WEAK SURFACE LOW NEARLY CO-LOCATED WITH NICE SHORTWAVE DIGGING IN
ACROSS SOUTH DAKOTA THIS AFTERNOON. THE COMBINATION OF SURFACE
HEATING...WEAK MOISTURE TRANSPORT AND LIFT IS PROMOTING CONVECTIVE
INITIATION ACROSS SOUTHWEST MINNESOTA AND NORTHERN IOWA. THE CURRENT
SHOWERS EXTEND ALONG A NW-SE AXIS OF HIGHER PWATS /0.70"-0.90"/ PER
THE 19Z SURFACE RAP ANALYSIS. THE SBCAPE IS WEAK BUT THE APPROACH
SHORTWAVE IS HELPING TO STEEPEN THE MID LEVEL LAPSE RATE TO
7-7.5C/KM IN WESTERN MINNESOTA. THE UPPER FLOW IS PRETTY WEAK BUT
THERE SHOULD BE ENOUGH FORCING AND SHEAR TO PROMOTE MULTI-CELL
CONVECTIVE MODE AND A SLIGHT CHANCE FOR HAIL AND GUSTY WINDS WITH
THE STRONGEST UPDRAFTS. THIS IS ESPECIALLY TRUE FROM 4-7PM WHERE
THE SFC-6KM MAX LAYER THETA-E DIFFERENCE IS BETWEEN -15C AND -20C
IN WESTERN MN. FARTHER EAST IN EASTERN MN AND WESTERN WI...THE
CONVECTIVE POTENTIAL IS LOWER /ALTHOUGH THERE SHOULD STILL BE A
HEALTHY BAND OF SHOWERS WITH GOOD VERTICAL EXTENT AND IN-CLOUD
LIGHTNING/. MANY OF THE HI-RES WRF SIMULATIONS
/SPC...HOPWRF...NCEP/ HAVE THE RAIN CLEARING MN BY ABOUT 9PM AND
WESTERN WI BY ABOUT MIDNIGHT. THERE WILL BE A BREAK IN THE PRECIP
BEFORE ISENTROPIC LIFT WITH THE STRENGTHENING SOUTHERN PLAINS LOW
STARTS TO SPREAD SHOWERS AND STORMS INTO SOUTHERN MINNESOTA BY
TOMORROW AFTERNOON.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 235 PM CDT SAT MAY 10 2014
THE LONG TERM PORTION OF THE FORECAST WILL BE ACTIVE FROM THE GET-
GO...WITH A SURFACE TROUGH EXPECTED TO BE NOSING INTO SOUTHERN MN
AT 00Z MONDAY. THUNDERSTORMS /LIKELY SEVERE/ ARE EXPECTED TO BE
ONGOING TO THE SOUTH...WITH THE THREAT FOR STRONG THUNDERSTORMS
SHIFTING NORTH INTO SOUTH CENTRAL/EAST MN AND WEST CENTRAL WI ON
SUNDAY NIGHT AS THE INSTABILITY GRADIENT LIFTS NORTH. PRECIPITABLE
WATER VALUES INCREASE TO AROUND 200 PERCENT OF NORMAL /1.5
INCHES/...SO HEAVY RAIN PRODUCING THUNDERSTORMS ARE CERTAINLY A
POSSIBILITY AS LLVL MOISTURE TRANSPORT ENSUES SUNDAY NIGHT AND
MONDAY. COULD STILL POTENTIALLY SEE AMOUNTS CURTAILED A BIT DUE
TO THE CONVECTION TO THE SOUTH...BUT STILL THINK 1-2 INCH TOTALS
ARE QUITE POSSIBLE BETWEEN SUNDAY EVENING AND MONDAY MORNING ALONG
THE INTERSTATE 90 CORRIDOR OF SOUTH CENTRAL AND SOUTHEAST MN...AND
EAST OF INTERSTATE 35 FROM THE TWIN CITIES ACROSS WEST CENTRAL WI.
MONDAY AFTERNOON/EVE WILL BE ANOTHER WINDOW OF TIME WHEN STRONG TO
SEVERE STORMS COULD SKIRT THE SOUTHEASTERN BORDER OF THE FORECAST
AREA...NAMELY ACROSS WEST CENTRAL WI. MONDAY NIGHT AND TUESDAY THE
MID LEVEL TROUGH PIVOTS ACROSS THE AREA AND SUPPLIES ANOTHER ROUND
OF SHOWERS...ALTHOUGH THE THUNDER POTENTIAL WILL HAVE LOWERED
NOTABLY AND COVERAGE SHOULD BE MORE SCATTERED IN NATURE.
MODEL TRENDS FOR WEDNESDAY...PARTICULARLY THE 10.12Z ECMWF WERE TO
KEEP THE NORTHERN AND SOUTHERN STREAM ENERGY A BIT MORE
DISJOINTED...HENCE LEAVING THE LOCAL AREA IN BETWEEN THE MAIN
AREAS OF FORCING. HOWEVER...COULD STILL SEE A FEW INSTABILITY
SHOWERS ON WEDNESDAY THROUGH THE END OF THE WEEK AS THE NORTHERN
STREAM TROUGH SAGS INTO THE UPPER MIDWEST AND GREAT LAKES REGION.
NO SURPRISE THAT TEMPERATURES WILL BE COOL NEXT WEEK...AS H85
TEMPERATURES FLIRT WITH 0 CELSIUS FROM TUESDAY THROUGH FRIDAY.
WILL NEED TO MONITOR THE POTENTIAL FOR FROST DURING THE OVERNIGHT
PERIODS...WITH THE GROWING SEASON NEARING.
BETTER NEWS /IN THE FORM OF WARMER TEMPERATURES/ IS EXPECTED TO
ARRIVE FOR NEXT WEEKEND...AS THE TROUGH LIFTS TO HUDSON BAY AND
WESTERN RIDGING BUILDS TOWARD THE CENTRAL CONUS. EXPECT TO SEE 60S
BACK IN THE FORECAST FOR NEXT SATURDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 705 PM CDT SAT MAY 10 2014
A BAND OF SHOWERS AND THUNDERSTORMS FROM AXN TO RWF AND MKT WILL
CONTINUE TO LIFT NORTHEAST THROUGH THE EVENING. WANING INSTABILITY
TO THE NORTHEAST ACROSS EAST CENTRAL MN AND WEST CENTRAL MN WILL
LIMIT THE THUNDER POTENTIAL...BUT CONTINUED THE MENTION AT MSP AND
STC. CANNOT RULE OUT BRIEF MVFR CONDITIONS WITH THE SHOWERS...BUT VFR
CONDITIONS EXPECTED THROUGH THE PERIOD AFTER.
KMSP...SHOWERS WILL BEGIN ABOUT 01Z AND PERSIST FOR A COUPLE HOURS.
VFR CONDITIONS ARE EXPECTED THROUGHOUT THE PERIOD.
/OUTLOOK FOR KMSP/
SUN NIGHT...MVFR POSSIBLE. -TSRA LIKELY. WINDS NE 10 KTS.
MON...MVFR LIKELY. IFR POSSIBLE. -SHRA LIKELY. WINDS NW 10KTS.
TUE...MVFR POSSIBLE. ISO-SCT -SHRA. WINDS W-NW 15-20KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...CLF
LONG TERM...LS
AVIATION...BORGHOFF
AREA FORECAST DISCUSSION
NWS DULUTH MN
1248 PM CDT FRI MAY 9 2014
.UPDATE...
ISSUED AT CDT FRI MAY 9 2014
THE FOCUS FOR THIS UPDATE WAS THE DENSE FOG OVER WESTERN LAKE
SUPERIOR AND AREAS ALONG THE NORTH AND SOUTH SHORE...AS WELL AS
THE RAIN SHOWERS FOR TODAY AND THIS EVENING.
THE MODELS ARE SUGGESTING THE FOG WILL LINGER ALONG THE NORTH
SHORE LONGEST...PROBABLY TILL MID AFTERNOON...SO I EXTENDED THE
DENSE FOG ADVISORY FOR THE NORTH SHORE UNTIL 3 PM. THE HRRR SEEMED
TO BE DOING FAIRLY WELL WITH THE CURRENT COVERAGE OF DENSE
FOG...SO I LEANED ON THE HRRR FOR THE AFTERNOON FORECAST. THE FOG
NEAR THE TWIN PORTS SHOULD BEGIN TO LIFT VERY LATE THIS
MORNING...SO I ONLY EXTENDED THAT PART OF THE ADVISORY TILL NOON.
THE NORTHWEST WINDS DEVELOPING BEHIND THE PASSING LOW PRESSURE
SYSTEM WILL ALSO BE HELPING TO DISSIPATE THE FOG.
WE MAY HAVE HAD PCPN ENDING TOO QUICKLY...AND DID NOT HAVE HIGH
ENOUGH PCPN CHANCES ACROSS THE NORTHERN FORECAST AREA. THE MODELS
ARE IN GOOD AGREEMENT WITH THE PCPN LINGERING LONGER THAN THE
PREVIOUS FORECAST...SO I DELAYED ITS DISSIPATION AND/OR EXIT FROM
THE FORECAST AREA THROUGH THIS EVENING.
UPDATE ISSUED AT 620 AM CDT FRI MAY 9 2014
UPDATED FOR AVIATION DISCUSSION.
&&
.SYNOPSIS...
ISSUED AT 354 AM CDT FRI MAY 9 2014
SURFACE LOW CURRENTLY JUST NORTHEAST OF KSTL IS GRADUALLY MOVING
NORTHEAST...WITH SOME FAIRLY STRONG PRESSURE FALLS AND AN INVERTED
TROUGH OVER THE ARROWHEAD THIS MORNING. EXTENDING FROM CENTRAL
WISCONSIN UP OVER WESTERN UPPER MICHIGAN AND LAKE SUPERIOR IS A BAND
OF SHOWERS AND THUNDERSTORMS THAT MOVED OVER THE FORECAST AREA
OVERNIGHT. OVER WESTERN MINNESOTA...EASTERN NORTH AND SOUTH DAKOTA
IS AN AREA OF RAIN SHOWERS IN THE WRAP AROUND PORTION OF THE
STORM...ACCOMPANIED BY A NICE PV ANOMALY INDICATIVE OF A TROWAL.
THE SURFACE WARM FRONT EXTENDS EAST FROM THE SURFACE LOW ALONG THE
DEWPOINT DISCONTINUITY OVER NORTHERN WISCONSIN AND INTO UPPER
MICHIGAN. THE COLD FRONT EXTENDS SOUTH FROM THE LOW...AND IS
PLOWING EAST ACROSS IOWA AND MISSOURI. IN THE CONVERGENT AREA AHEAD
OF THE SURFACE LOW WHERE WINDS ARE LIGHT AND DEWPOINT DEPRESSIONS
ARE LOW...AREAS OF FOG HAVE DEVELOPED. IT SEEMS MOST WIDESPREAD
WHERE SOME OF THE COOLER MARINE LAYER HAS SLOPPED ASHORE IN THE
LIGHT NORTHEAST FLOW.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 354 AM CDT FRI MAY 9 2014
THE SURFACE LOW WILL CONTINUE TO MOVE NORTHEAST TODAY...EXITING
TO CENTRAL ONTARIO BY 18Z TODAY. THE AREAS OF DENSE FOG MENTIONED
ABOVE HAVE BEEN PERSISTENT MOST OF THE NIGHT AHEAD OF THE
LOW...AND HAVE DECIDED TO ISSUE A DENSE FOG FOR THE NORTH SHORE
AND AREAS AROUND THE HEAD OF THE LAKE UNTIL MID MORNING. AS THE
SURFACE LOW MOVES ACROSS THE AREA THE WIND DIRECTION WILL TURN
AROUND TO THE NORTHWEST...SOME DRIER AIR WILL BEGIN TO WORK INTO
THE AREA EVEN IF TEMPERATURES DONT CHANGE MUCH...SO EXPECT THE FOG
TO DISSIPATE BY MID MORNING.
THE SHOWERS THIS MORNING OVER THE FAR NORTHEASTERN CWA SHOULD MOVE OFF
TO THE EAST...LEAVING THAT PART OF THE FORECAST AREA MOSTLY DRY.
THE AREA OF SHOWERS ASSOCIATED WITH THE TROWAL ARE GOING TO SWEEP
ACROSS THE FORECAST AREA TODAY AND EARLY THIS EVENING...MAINLY
OVER NORTHERN MINNESOTA. AM FAIRLY CONFIDENT IN THIS AREA OF
PRECIPITATION...SO HAVE RAISED POPS SOMEWHAT AND REFINED TIMING
SOMEWHAT. UNDER THIS AREA OF SHOWERS TEMPERATURES ARE GOING TO
ONLY GET INTO THE UPPER 40S TO AROUND 50...WITH HIGHS IN THE MID
TO UPPER 50S MOST OTHER LOCATIONS. TEMPERATURES EARLY THIS MORNING
ARE IN THE UPPER 50S TO LOWER 60S OVER PORTIONS OF NORTHWEST
WISCONSIN WHERE THEY ARE IN THE WARM SECTOR. EXPECT THAT THEY ARE
AT OR NEAR THEIR HIGHS FOR TODAY...AND WILL ONLY REMAIN STEADY OR
SLOWLY FALL THE REST OF THE DAY. TONIGHT THE SHOWERS WILL STILL BE
AFFECTING THE ARROWHEAD REGION IN THE EVENING...BUT A THERE WILL
BE A GRADUAL CLEARING TREND SETTING UP FROM SOUTHWEST TO NORTHEAST
AS THE STORM GRADUALLY MOVES OFF TO THE NORTHEAST TONIGHT. EXPECT
TEMPERATURES TO FALL OFF INTO THE MID 30S MOST LOCATIONS...AS I
EXPECT CLEARING TO OCCUR FOR NEARLY THE WHOLE CWA BY EARLY
MORNING. WINDS WILL DROP OFF ENOUGH FOR RADIATIONAL COOLING TO BE
FAIRLY SIGNIFICANT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 354 AM CDT FRI MAY 9 2014
A NARROW RIDGE OF HIGH PRESSURE ALOFT AND AT THE SURFACE WILL BUILD
IN SAT MORNING WITH DRY CONDITIONS AND MOSTLY SUNNY SKIES THROUGH
MOST OF THE DAY. A WEAK UPPER S/W AND ASSOCIATED SFC TROUGH WILL
LIFT E/NEWD FROM THE DAKOTAS INTO MN AND WRN LAKE SUPERIOR LATER IN
THE DAY SATURDAY AND ESPECIALLY SAT NIGHT. THIS SYSTEM WILL PRODUCE
ANOTHER ROUND OF WIDESPREAD RAIN SHOWERS AND A FEW WEAK
THUNDERSTORMS. THE SFC BOUNDARY WILL STALL OUT AS IT LIFTS NWD INTO
NRN MN AND AWAIT THE NEXT SURGE OF WARM MOIST AIR LATE IN THE
WEEKEND...ALONG WITH THE NEXT LOW PRESSURE SYSTEM EXPECTED TO TRACK
SW TO NE OVER THE UPPER MIDWEST MON INTO TUE MORNING. THIS SYSTEM
WILL ONCE AGAIN BE LOADED WITH MOISTURE AND ALSO DRAW UP A SLIGHTLY
UNSTABLE AIR MASS TO PRODUCE ISOLATED THUNDERSTORMS AND THE
POTENTIAL FOR LOCALLY HEAVY RAINFALL. AS THE SFC LOW APPROACHES FROM
THE SW...PRESSURE FALLS WILL INDUCE A STRONG NE FLOW OFF LAKE
SUPERIOR AND COMBINE WITH FAIRLY STRONG WAA IN THE MID/LOW LVLS TO
PRODUCE ANOTHER PERIOD OF COOL/CLOUDY/FOGGY CONDITIONS AROUND THE
PERIPHERY OF THE LAKE. THE PRESENCE OF THIS COOL/STABLE NEAR-SFC
LAYER WILL KEEP ANY STORMS ELEVATED THAT TRACK TO THE
NORTH...KEEPING THE THREAT OF STRONG/SEVERE WX ON THE LOW SIDE. AN
UNSEASONABLY COLD AIR MASS WILL ADVECT IN ON THE BACK SIDE OF THIS
SYSTEM AS IT DEPARTS TO THE EAST LATE TUE AND WED. THE AIR PUSHING
IN FROM THE NW COULD BE COLD ENOUGH TO ALLOW FOR A FEW LIGHT SNOW
SHOWERS TO MIX IN LATE TUE NIGHT...AND AGAIN LATE WED NIGHT. 850MB
TEMPS WILL BE ROUGHLY -5 TO -10 DEG C. YES IT IS ALMOST THE MIDDLE
OF MAY. WILL SEE SLIGHT IMPROVEMENT INTO THURSDAY AS HIGH PRESSURE
GRADUALLY BUILDS IN ACROSS THE MIDWEST. HOWEVER IT WILL NOT BE UNTIL
THE WEEKEND UNTIL TEMPS REACH BACK TO NEAR NORMAL.
TEMPERATURES THIS WEEKEND WILL BE AT OR SLIGHTLY ABOVE NORMAL WITH
LIGHT AND VARIABLE WINDS. SATURDAY WILL LIKELY BE THE MOST PLEASANT
DAY WITH DRY CONDITIONS EXPECTED. THE TEMP TREND WILL BEGIN A
DOWNWARD SLIDE MON THROUGH WED WITH HIGHS IN THE 40S AND 50S AND
OVERNIGHT LOWS IN THE 30S. A GRADUAL WARMING TREND WILL NOT BE FELT
UNTIL THE LATTER HALF OF THE WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1248 PM CDT FRI MAY 9 2014
A MIX OF IFR/LOW END MVFR CONDITIONS COVERED THE NORTHLAND THIS
AFTERNOON. AREAS OF LIGHT RAIN OR DRIZZLE WERE ALSO OCCURRING. THE
AREA OF LOW PRESSURE THAT HAS IMPACTED THE REGION FOR THE PAST
COUPLE DAYS WILL CONTINUE TO MOVE OFF...AND CONDITIONS WILL
GRADUALLY IMPROVE FROM WEST TO EAST. CEILINGS WILL CLEAR FROM WEST
TO EAST LATE THIS AFTERNOON INTO THE LATE EVENING HOURS. GUSTY
WEST TO NORTHWEST WINDS WILL DEVELOP...THEN DIMINISH THIS EVENING
AS THE GRADIENT WEAKENS.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 51 38 63 48 / 60 40 10 60
INL 50 34 67 44 / 80 40 0 50
BRD 55 36 64 46 / 70 10 40 50
HYR 57 38 67 47 / 70 30 10 60
ASX 59 38 64 45 / 40 40 0 60
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...DENSE FOG ADVISORY UNTIL 3 PM CDT THIS AFTERNOON FOR MNZ020-021.
WI...NONE.
LS...SMALL CRAFT ADVISORY UNTIL 4 AM CDT SATURDAY FOR LSZ143>147.
DENSE FOG ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR LSZ140-141.
&&
$$
UPDATE...GROCHOCINSKI
SYNOPSIS...LE
SHORT TERM...LE
LONG TERM...BJT
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1215 PM CDT FRI MAY 9 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 340 AM CDT FRI MAY 9 2014
RAP ANALYZED SURFACE LOW JUST SOUTH OF DULUTH EARLY THIS MORNING.
AREAS WEST OF THE METRO HAVE SEEN THE WINDS TURN WESTERLY AND PICK
UP IN INTENSITY. COLD AIR ADVECTION IS ONGOING IN THESE AREAS...AND
WILL CONTINUE TO SPREAD ACROSS THE REMAINDER OF THE FORECAST AREA
TODAY. THE SURFACE LOW WILL SLOWLY CONTINUE NORTHEASTWARD...AS THE
WESTERLY WINDS TAKE MUCH OF THE DAY TO SPREAD ACROSS WEST CENTRAL
WISCONSIN. ABUNDANT LOW LEVEL MOISTURE WILL ALLOW FOR LOW LCL
HEIGHTS WHICH IS CURRENTLY NOTICEABLE IN THE OBSERVATIONS BEHIND THE
COLD FRONT WHERE CEILINGS UNDER 1K FEET ARE PRESENT. RAP AND NAM
MODEL SOUNDINGS INDICATE THIS MOISTURE STICKING AROUND FOR MUCH OF
THE DAY...SO TRENDED TOWARD A MORE PESSIMISTIC SKY COVER FORECAST
AND HENCE LOWERED MAX TEMPERATURES TODAY BY A FEW DEGREES ACROSS THE
FA. MAX TEMPS WILL BE ABOUT 10 DEGREES BELOW SEASONAL NORMALS FOR
THIS TIME OF YEAR. IN ADDITION...WRAP AROUND LIGHT RAIN SHOWERS ARE
EXPECTED TO MOVE ACROSS THE NORTHERN PORTION OF THE CWA AS THEY
CYCLONIC CIRCULATION ALOFT REMAINS BETTER TOWARD THE NORTH /AS WELL
AS AT LEAST SOME FGEN AND FN VECTOR CONVERGENCE/. SKIES WILL BEGIN
CLEARING LATE THIS AFTERNOON AND MOSTLY CLEAR SKIES ARE EXPECTED
OVERNIGHT...EXCEPT CLOUDS WILL QUICKLY BEGIN FILLING IN FROM THE
SOUTHWEST EARLY SATURDAY MORNING.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 340 AM CDT FRI MAY 9 2014
AN UNSETTLED PERIOD REMAINS FORECAST FOR MUCH OF THE LONGER TERM
AS NORTHERN AND SOUTHERN STREAM ENERGY EVENTUALLY PHASE OVER THE
CENTER OF THE COUNTRY AROUND THE MIDDLE OF NEXT WEEK. THIS PROCESS
OCCURS THE FASTEST WITH THE GFS WHILE DP/DT SHOWS THAT THE SLOWER
ECMWF IS BECOMING EVEN SLOWER WITH TIME.
ON SATURDAY...A WAVE MOVING IN FROM THE CENTRAL PLAINS WILL BRING
THICKENING CLOUDINESS AND SHOWERS BACK ACROSS THE FA FROM SW TO NE
DURING THE DAY. A BRIEF BREAK IN THE PRECIPITATION IS EXPECTED
SATURDAY NIGHT BEFORE A MORE POTENT WAVE BEGINS TO TAKE SHAPE OVER
THE CENTRAL PLAINS ON SUNDAY. THIS WAVE IS BEING DRIVEN BY THE
SOUTHERN STREAM ENERGY. USING THE SLOWER ECWMF...THE LOW IN THE
PLAINS TAKES UNTIL MONDAY EVENING TO ARRIVE IN SE MN. THIS PLACES
MUCH OF THE FA IN LOW LEVEL THETA-E ADVECTION FROM SUNDAY THROUGH
MONDAY...WITH SOUTHERN MN BEARING THE BRUNT OF IT. HENCE...LIKELY
POPS STREAM BACK IN ON SUNDAY FROM THE SOUTHWEST AND PERSIST THROUGH
MONDAY. WIDESPREAD HALF INCH TO ONE INCH RAINFALL IS LIKELY DURING
THIS PERIOD WITH SOME TWO INCH AMOUNTS OVER SOUTHERN MN. THERE WILL
CERTAINLY BE THE THREAT FOR SOME THUNDERSTORMS...ESPECIALLY ON
MONDAY FROM THE TWIN CITIES ON EAST AND SOUTH. STRICTLY USING THE
ECMWF TIMING WOULD INDICATE A WINDOW OF OPPORTUNITY FOR STRONG TO
SEVERE STORMS MONDAY AFTERNOON/EVENING TO THE SOUTH AND EAST OF
THE TWIN CITIES.
THE SHOWERS WILL BEGIN TO TAPER OFF MONDAY NIGHT AS THE LOW
PRESSURE SYSTEM MOVES NORTHEAST OF THE FA. INSTABILITY SHOWERS ARE
POSSIBLE MAINLY FROM CENTRAL MINNESOTA ON NORTHWARD ON TUESDAY.
SCATTERED SHOWERS ARE BACK FOR MUCH OF THE FA WEDNESDAY AND
THURSDAY AS THE UPPER TROUGH COMES TOGETHER FROM THE UPPER
MISSISSIPPI VALLEY TO THE GULF COAST. HIGH TEMPERATURES WILL BE
CLOSE TO NORMAL THIS WEEKEND...BUT THEN RETREAT TO SOME 10 TO 15
DEGREES BELOW NORMAL FOR THE MIDDLE TO END OF NEXT WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1204 PM CDT FRI MAY 9 2014
MVFR CIGS REMAIN OVER PARTS MUCH OF THE CENTRAL AND EAST INTO THE
AFTERNOON. GRADUALLY BECOMING VFR AND SKC FROM WEST TO EAST AS THE
UPPER TROUGH MOVES EAST. SOME CHANCE OF -SHRA OVER THE NORTHEAST
CWA INTO THE AFTERNOON AS WELL. EXPECT WEST TO NORTHWEST WINDS
13-17KTS WITH GUSTS TO 25-29KTS OVER THE AREA INTO THE
AFTERNOON...BEFORE DIMINISHING FROM WEST TO EAST BY EVENING.
LIGHTER WINDS OVERNIGHT AS SURFACE HIGH MOVES THROUGH....BECOMING
SOUTHEAST INTO SATURDAY AND INCREASING AHEAD OF NEXT TROUGH. SHOULD
SEE SOME MID/HIGH LEVEL CLOUDS INCREASE AGAIN OVER THE WESTERN
AREA LATER TONIGHT AND SATURDAY MORNING...BUT REMAINING VFR. COULD
SEE SOME -SHRA MOVE IN TOWARDS KRWF 15Z-18Z BUT CONFIDENCE IS LOW
ON HOW FAST MOISTURE WILL RETURN AND SATURATE. KEPT IT DRY FOR
NOW.
KMSP...CIGS LIFTING TO MVFR LATE AFTERNOON. CLEARING BY EARLY
EVENING AS UPPER TROUGH EXITS EAST. SURFACE HIGH MOVES OVER THE
AREA TONIGHT WITH LIGHT WINDS BECOMING SOUTHEAST AND INCREASING
SATURDAY MORNING. MID/HIGH LEVEL CLOUDS SPREAD EAST SATURDAY
MORNING WITH SOME CHANCE OF -SHRA IN THE AFTERNOON. LEFT IT AS
VCSH FOR NOW...AS SOUTHEAST FLOW WILL BE DRY INITIALLY.
/OUTLOOK FOR KMSP/
SAT NITE...VFR. CHC -SHRA/-TSRA. WINDS SSE 10KTS.
SUN...MVFR POSSIBLE. LIKELY -SHRA. WINDS SW TO NW 10-15 KTS.
MON...MVFR POSSIBLE. LIKELY -SHRA. WINDS NW 10KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...SPD
LONG TERM...RAH
AVIATION...DWE
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1035 AM CDT FRI MAY 9 2014
.UPDATE...
ISSUED AT CDT FRI MAY 9 2014
THE FOCUS FOR THIS UPDATE WAS THE DENSE FOG OVER WESTERN LAKE
SUPERIOR AND AREAS ALONG THE NORTH AND SOUTH SHORE...AS WELL AS
THE RAIN SHOWERS FOR TODAY AND THIS EVENING.
THE MODELS ARE SUGGESTING THE FOG WILL LINGER ALONG THE NORTH
SHORE LONGEST...PROBABLY TILL MID AFTERNOON...SO I EXTENDED THE
DENSE FOG ADVISORY FOR THE NORTH SHORE UNTIL 3 PM. THE HRRR SEEMED
TO BE DOING FAIRLY WELL WITH THE CURRENT COVERAGE OF DENSE
FOG...SO I LEANED ON THE HRRR FOR THE AFTERNOON FORECAST. THE FOG
NEAR THE TWIN PORTS SHOULD BEGIN TO LIFT VERY LATE THIS
MORNING...SO I ONLY EXTENDED THAT PART OF THE ADVISORY TILL NOON.
THE NORTHWEST WINDS DEVELOPING BEHIND THE PASSING LOW PRESSURE
SYSTEM WILL ALSO BE HELPING TO DISSIPATE THE FOG.
WE MAY HAVE HAD PCPN ENDING TOO QUICKLY...AND DID NOT HAVE HIGH
ENOUGH PCPN CHANCES ACROSS THE NORTHERN FORECAST AREA. THE MODELS
ARE IN GOOD AGREEMENT WITH THE PCPN LINGERING LONGER THAN THE
PREVIOUS FORECAST...SO I DELAYED ITS DISSIPATION AND/OR EXIT FROM
THE FORECAST AREA THROUGH THIS EVENING.
UPDATE ISSUED AT 620 AM CDT FRI MAY 9 2014
UPDATED FOR AVIATION DISCUSSION.
&&
.SYNOPSIS...
ISSUED AT 354 AM CDT FRI MAY 9 2014
SURFACE LOW CURRENTLY JUST NORTHEAST OF KSTL IS GRADUALLY MOVING
NORTHEAST...WITH SOME FAIRLY STRONG PRESSURE FALLS AND AN INVERTED
TROUGH OVER THE ARROWHEAD THIS MORNING. EXTENDING FROM CENTRAL
WISCONSIN UP OVER WESTERN UPPER MICHIGAN AND LAKE SUPERIOR IS A BAND
OF SHOWERS AND THUNDERSTORMS THAT MOVED OVER THE FORECAST AREA
OVERNIGHT. OVER WESTERN MINNESOTA...EASTERN NORTH AND SOUTH DAKOTA
IS AN AREA OF RAIN SHOWERS IN THE WRAP AROUND PORTION OF THE
STORM...ACCOMPANIED BY A NICE PV ANOMALY INDICATIVE OF A TROWAL.
THE SURFACE WARM FRONT EXTENDS EAST FROM THE SURFACE LOW ALONG THE
DEWPOINT DISCONTINUITY OVER NORTHERN WISCONSIN AND INTO UPPER
MICHIGAN. THE COLD FRONT EXTENDS SOUTH FROM THE LOW...AND IS
PLOWING EAST ACROSS IOWA AND MISSOURI. IN THE CONVERGENT AREA AHEAD
OF THE SURFACE LOW WHERE WINDS ARE LIGHT AND DEWPOINT DEPRESSIONS
ARE LOW...AREAS OF FOG HAVE DEVELOPED. IT SEEMS MOST WIDESPREAD
WHERE SOME OF THE COOLER MARINE LAYER HAS SLOPPED ASHORE IN THE
LIGHT NORTHEAST FLOW.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 354 AM CDT FRI MAY 9 2014
THE SURFACE LOW WILL CONTINUE TO MOVE NORTHEAST TODAY...EXITING
TO CENTRAL ONTARIO BY 18Z TODAY. THE AREAS OF DENSE FOG MENTIONED
ABOVE HAVE BEEN PERSISTENT MOST OF THE NIGHT AHEAD OF THE
LOW...AND HAVE DECIDED TO ISSUE A DENSE FOG FOR THE NORTH SHORE
AND AREAS AROUND THE HEAD OF THE LAKE UNTIL MID MORNING. AS THE
SURFACE LOW MOVES ACROSS THE AREA THE WIND DIRECTION WILL TURN
AROUND TO THE NORTHWEST...SOME DRIER AIR WILL BEGIN TO WORK INTO
THE AREA EVEN IF TEMPERATURES DONT CHANGE MUCH...SO EXPECT THE FOG
TO DISSIPATE BY MID MORNING.
THE SHOWERS THIS MORNING OVER THE FAR NORTHEASTERN CWA SHOULD MOVE OFF
TO THE EAST...LEAVING THAT PART OF THE FORECAST AREA MOSTLY DRY.
THE AREA OF SHOWERS ASSOCIATED WITH THE TROWAL ARE GOING TO SWEEP
ACROSS THE FORECAST AREA TODAY AND EARLY THIS EVENING...MAINLY
OVER NORTHERN MINNESOTA. AM FAIRLY CONFIDENT IN THIS AREA OF
PRECIPITATION...SO HAVE RAISED POPS SOMEWHAT AND REFINED TIMING
SOMEWHAT. UNDER THIS AREA OF SHOWERS TEMPERATURES ARE GOING TO
ONLY GET INTO THE UPPER 40S TO AROUND 50...WITH HIGHS IN THE MID
TO UPPER 50S MOST OTHER LOCATIONS. TEMPERATURES EARLY THIS MORNING
ARE IN THE UPPER 50S TO LOWER 60S OVER PORTIONS OF NORTHWEST
WISCONSIN WHERE THEY ARE IN THE WARM SECTOR. EXPECT THAT THEY ARE
AT OR NEAR THEIR HIGHS FOR TODAY...AND WILL ONLY REMAIN STEADY OR
SLOWLY FALL THE REST OF THE DAY. TONIGHT THE SHOWERS WILL STILL BE
AFFECTING THE ARROWHEAD REGION IN THE EVENING...BUT A THERE WILL
BE A GRADUAL CLEARING TREND SETTING UP FROM SOUTHWEST TO NORTHEAST
AS THE STORM GRADUALLY MOVES OFF TO THE NORTHEAST TONIGHT. EXPECT
TEMPERATURES TO FALL OFF INTO THE MID 30S MOST LOCATIONS...AS I
EXPECT CLEARING TO OCCUR FOR NEARLY THE WHOLE CWA BY EARLY
MORNING. WINDS WILL DROP OFF ENOUGH FOR RADIATIONAL COOLING TO BE
FAIRLY SIGNIFICANT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 354 AM CDT FRI MAY 9 2014
A NARROW RIDGE OF HIGH PRESSURE ALOFT AND AT THE SURFACE WILL BUILD
IN SAT MORNING WITH DRY CONDITIONS AND MOSTLY SUNNY SKIES THROUGH
MOST OF THE DAY. A WEAK UPPER S/W AND ASSOCIATED SFC TROUGH WILL
LIFT E/NEWD FROM THE DAKOTAS INTO MN AND WRN LAKE SUPERIOR LATER IN
THE DAY SATURDAY AND ESPECIALLY SAT NIGHT. THIS SYSTEM WILL PRODUCE
ANOTHER ROUND OF WIDESPREAD RAIN SHOWERS AND A FEW WEAK
THUNDERSTORMS. THE SFC BOUNDARY WILL STALL OUT AS IT LIFTS NWD INTO
NRN MN AND AWAIT THE NEXT SURGE OF WARM MOIST AIR LATE IN THE
WEEKEND...ALONG WITH THE NEXT LOW PRESSURE SYSTEM EXPECTED TO TRACK
SW TO NE OVER THE UPPER MIDWEST MON INTO TUE MORNING. THIS SYSTEM
WILL ONCE AGAIN BE LOADED WITH MOISTURE AND ALSO DRAW UP A SLIGHTLY
UNSTABLE AIR MASS TO PRODUCE ISOLATED THUNDERSTORMS AND THE
POTENTIAL FOR LOCALLY HEAVY RAINFALL. AS THE SFC LOW APPROACHES FROM
THE SW...PRESSURE FALLS WILL INDUCE A STRONG NE FLOW OFF LAKE
SUPERIOR AND COMBINE WITH FAIRLY STRONG WAA IN THE MID/LOW LVLS TO
PRODUCE ANOTHER PERIOD OF COOL/CLOUDY/FOGGY CONDITIONS AROUND THE
PERIPHERY OF THE LAKE. THE PRESENCE OF THIS COOL/STABLE NEAR-SFC
LAYER WILL KEEP ANY STORMS ELEVATED THAT TRACK TO THE
NORTH...KEEPING THE THREAT OF STRONG/SEVERE WX ON THE LOW SIDE. AN
UNSEASONABLY COLD AIR MASS WILL ADVECT IN ON THE BACK SIDE OF THIS
SYSTEM AS IT DEPARTS TO THE EAST LATE TUE AND WED. THE AIR PUSHING
IN FROM THE NW COULD BE COLD ENOUGH TO ALLOW FOR A FEW LIGHT SNOW
SHOWERS TO MIX IN LATE TUE NIGHT...AND AGAIN LATE WED NIGHT. 850MB
TEMPS WILL BE ROUGHLY -5 TO -10 DEG C. YES IT IS ALMOST THE MIDDLE
OF MAY. WILL SEE SLIGHT IMPROVEMENT INTO THURSDAY AS HIGH PRESSURE
GRADUALLY BUILDS IN ACROSS THE MIDWEST. HOWEVER IT WILL NOT BE UNTIL
THE WEEKEND UNTIL TEMPS REACH BACK TO NEAR NORMAL.
TEMPERATURES THIS WEEKEND WILL BE AT OR SLIGHTLY ABOVE NORMAL WITH
LIGHT AND VARIABLE WINDS. SATURDAY WILL LIKELY BE THE MOST PLEASANT
DAY WITH DRY CONDITIONS EXPECTED. THE TEMP TREND WILL BEGIN A
DOWNWARD SLIDE MON THROUGH WED WITH HIGHS IN THE 40S AND 50S AND
OVERNIGHT LOWS IN THE 30S. A GRADUAL WARMING TREND WILL NOT BE FELT
UNTIL THE LATTER HALF OF THE WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 620 AM CDT FRI MAY 9 2014
LIFR CIGS AND VSBYS WILL PERSIST THIS MORNING WITH GRADUAL
IMPROVEMENT THROUGH THE AFTERNOON AS THE LOW PRESSURE SYSTEM LIFTS
NEWD ACROSS THE NORTHLAND. WILL SEE A BAND OF RAIN SHOWERS ON THE
BACK SIDE OF THIS SYSTEM ROTATE EWD THROUGH THE REGION THIS
MORNING AND INTO THE AFTERNOON...TAPERING OFF WEST TO EAST. CIGS
WILL LIFT TO MVFR AND EVENTUALLY VFR THIS AFTERNOON...WITH
CLEARING SKIES W-E EXPECTED THIS EVENING AND TONIGHT. WINDS
ROTATING AROUND THE SFC LOW TODAY WILL BE GUSTY...UP TO 15 TO 25
KNOTS. WINDS WILL DIMINISH TONIGHT.
&&
.PRELIMINARY POINT TEMPS/POPS...
DLH 51 37 63 48 / 60 40 10 60
INL 50 34 67 44 / 80 40 0 50
BRD 55 36 64 46 / 70 10 40 50
HYR 57 38 67 47 / 70 30 10 50
ASX 56 38 64 45 / 40 40 0 60
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...DENSE FOG ADVISORY UNTIL NOON CDT TODAY FOR MNZ037.
DENSE FOG ADVISORY UNTIL 3 PM CDT THIS AFTERNOON FOR MNZ020-021.
WI...DENSE FOG ADVISORY UNTIL NOON CDT TODAY FOR WIZ001.
LS...SMALL CRAFT ADVISORY UNTIL 4 AM CDT SATURDAY FOR LSZ143>147.
DENSE FOG ADVISORY UNTIL 11 AM CDT THIS MORNING FOR LSZ144-145.
DENSE FOG ADVISORY UNTIL 1 PM CDT THIS AFTERNOON FOR LSZ142-143.
DENSE FOG ADVISORY UNTIL 4 PM CDT THIS AFTERNOON FOR LSZ140-141.
&&
$$
UPDATE...GROCHOCINSKI
SYNOPSIS...LE
SHORT TERM...LE
LONG TERM...BJT
AVIATION...BJT
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
600 AM CDT FRI MAY 9 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 340 AM CDT FRI MAY 9 2014
RAP ANALYZED SURFACE LOW JUST SOUTH OF DULUTH EARLY THIS MORNING.
AREAS WEST OF THE METRO HAVE SEEN THE WINDS TURN WESTERLY AND PICK
UP IN INTENSITY. COLD AIR ADVECTION IS ONGOING IN THESE AREAS...AND
WILL CONTINUE TO SPREAD ACROSS THE REMAINDER OF THE FORECAST AREA
TODAY. THE SURFACE LOW WILL SLOWLY CONTINUE NORTHEASTWARD...AS THE
WESTERLY WINDS TAKE MUCH OF THE DAY TO SPREAD ACROSS WEST CENTRAL
WISCONSIN. ABUNDANT LOW LEVEL MOISTURE WILL ALLOW FOR LOW LCL
HEIGHTS WHICH IS CURRENTLY NOTICEABLE IN THE OBSERVATIONS BEHIND THE
COLD FRONT WHERE CEILINGS UNDER 1K FEET ARE PRESENT. RAP AND NAM
MODEL SOUNDINGS INDICATE THIS MOISTURE STICKING AROUND FOR MUCH OF
THE DAY...SO TRENDED TOWARD A MORE PESSIMISTIC SKY COVER FORECAST
AND HENCE LOWERED MAX TEMPERATURES TODAY BY A FEW DEGREES ACROSS THE
FA. MAX TEMPS WILL BE ABOUT 10 DEGREES BELOW SEASONAL NORMALS FOR
THIS TIME OF YEAR. IN ADDITION...WRAP AROUND LIGHT RAIN SHOWERS ARE
EXPECTED TO MOVE ACROSS THE NORTHERN PORTION OF THE CWA AS THEY
CYCLONIC CIRCULATION ALOFT REMAINS BETTER TOWARD THE NORTH /AS WELL
AS AT LEAST SOME FGEN AND FN VECTOR CONVERGENCE/. SKIES WILL BEGIN
CLEARING LATE THIS AFTERNOON AND MOSTLY CLEAR SKIES ARE EXPECTED
OVERNIGHT...EXCEPT CLOUDS WILL QUICKLY BEGIN FILLING IN FROM THE
SOUTHWEST EARLY SATURDAY MORNING.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 340 AM CDT FRI MAY 9 2014
AN UNSETTLED PERIOD REMAINS FORECAST FOR MUCH OF THE LONGER TERM
AS NORTHERN AND SOUTHERN STREAM ENERGY EVENTUALLY PHASE OVER THE
CENTER OF THE COUNTRY AROUND THE MIDDLE OF NEXT WEEK. THIS PROCESS
OCCURS THE FASTEST WITH THE GFS WHILE DP/DT SHOWS THAT THE SLOWER
ECMWF IS BECOMING EVEN SLOWER WITH TIME.
ON SATURDAY...A WAVE MOVING IN FROM THE CENTRAL PLAINS WILL BRING
THICKENING CLOUDINESS AND SHOWERS BACK ACROSS THE FA FROM SW TO NE
DURING THE DAY. A BRIEF BREAK IN THE PRECIPITATION IS EXPECTED
SATURDAY NIGHT BEFORE A MORE POTENT WAVE BEGINS TO TAKE SHAPE OVER
THE CENTRAL PLAINS ON SUNDAY. THIS WAVE IS BEING DRIVEN BY THE
SOUTHERN STREAM ENERGY. USING THE SLOWER ECWMF...THE LOW IN THE
PLAINS TAKES UNTIL MONDAY EVENING TO ARRIVE IN SE MN. THIS PLACES
MUCH OF THE FA IN LOW LEVEL THETA-E ADVECTION FROM SUNDAY THROUGH
MONDAY...WITH SOUTHERN MN BEARING THE BRUNT OF IT. HENCE...LIKELY
POPS STREAM BACK IN ON SUNDAY FROM THE SOUTHWEST AND PERSIST THROUGH
MONDAY. WIDESPREAD HALF INCH TO ONE INCH RAINFALL IS LIKELY DURING
THIS PERIOD WITH SOME TWO INCH AMOUNTS OVER SOUTHERN MN. THERE WILL
CERTAINLY BE THE THREAT FOR SOME THUNDERSTORMS...ESPECIALLY ON
MONDAY FROM THE TWIN CITIES ON EAST AND SOUTH. STRICTLY USING THE
ECMWF TIMING WOULD INDICATE A WINDOW OF OPPORTUNITY FOR STRONG TO
SEVERE STORMS MONDAY AFTERNOON/EVENING TO THE SOUTH AND EAST OF
THE TWIN CITIES.
THE SHOWERS WILL BEGIN TO TAPER OFF MONDAY NIGHT AS THE LOW
PRESSURE SYSTEM MOVES NORTHEAST OF THE FA. INSTABILITY SHOWERS ARE
POSSIBLE MAINLY FROM CENTRAL MINNESOTA ON NORTHWARD ON TUESDAY.
SCATTERED SHOWERS ARE BACK FOR MUCH OF THE FA WEDNESDAY AND
THURSDAY AS THE UPPER TROUGH COMES TOGETHER FROM THE UPPER
MISSISSIPPI VALLEY TO THE GULF COAST. HIGH TEMPERATURES WILL BE
CLOSE TO NORMAL THIS WEEKEND...BUT THEN RETREAT TO SOME 10 TO 15
DEGREES BELOW NORMAL FOR THE MIDDLE TO END OF NEXT WEEK.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 547 AM CDT FRI MAY 9 2014
LOW PRESSURE CENTER LIFTING NORTHEAST TOWARD LAKE
SUPERIOR...LEAVING A SOLID LOW STRATUS DECK ACROSS MINNESOTA AND
WESTERN WISCONSIN. MODELS HAVE BECOME MORE PESSIMISTIC OVER THE
LAST 2 RUNS IN HANDLING THIS MOISTURE...AND CLOSELY FOLLOWED
UPDATED GUIDANCE TO HOLD CIGS IN THE IFR/MVFR RANGE FOR MOST OF
TODAY...WITH PERIODS OF LIFR POSSIBLE. THERE HAS BEEN SOME PATCHY
FOG THROUGH THE OVERNIGHT HOURS...WHICH HAS BEEN HARD TO PIN DOWN
BECAUSE IT IS WIDELY SCATTERED. THE CEILINGS HAVE BEEN BOUNCING A
BIT...ESPECIALLY AT EASTERN SITES. BOTH RAP AND NAM STILL INDICATE
LOW CIGS WITH GRADUAL LIFTING. SCATTERED SHOWERS WILL ROTATE
THROUGH THE NORTHERN HALF OF THE CWA. WINDS WILL REMAIN WESTERLY
AND CONTINUE GUSTING TODAY. SKIES WILL CLEAR OUT TONIGHT...AND
WINDS WILL BECOME LIGHT AND VARIABLE FOR A TIME.
KMSP...IFR CIGS WITH POSSIBLY LIFR AT TIMES WILL CONTINUE THIS
MORNING. IT LOOKS LIKE THE SCATTERED SHOWERS WILL SIDE SWIPE THE
TERMINAL...SO MAY STAY COMPLETELY DRY...BUT DID FEEL INCLINED TO
INCLUDE A MENTION OF LIGHT PRECIPITATION TODAY.
/OUTLOOK FOR KMSP/
SAT...VFR. CHC -TSRA. WINDS SSE 10KTS.
SUN...MVFR POSSIBLE. LIKELY -SHRA. WINDS SW TO NW 10-15 KTS.
MON...MVFR POSSIBLE. LIKELY -SHRA. WINDS NW 10KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...SPD
LONG TERM...RAH
AVIATION...SPD
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
340 AM CDT FRI MAY 9 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 340 AM CDT FRI MAY 9 2014
RAP ANALYZED SURFACE LOW JUST SOUTH OF DULUTH EARLY THIS MORNING.
AREAS WEST OF THE METRO HAVE SEEN THE WINDS TURN WESTERLY AND PICK
UP IN INTENSITY. COLD AIR ADVECTION IS ONGOING IN THESE AREAS...AND
WILL CONTINUE TO SPREAD ACROSS THE REMAINDER OF THE FORECAST AREA
TODAY. THE SURFACE LOW WILL SLOWLY CONTINUE NORTHEASTWARD...AS THE
WESTERLY WINDS TAKE MUCH OF THE DAY TO SPREAD ACROSS WEST CENTRAL
WISCONSIN. ABUNDANT LOW LEVEL MOISTURE WILL ALLOW FOR LOW LCL
HEIGHTS WHICH IS CURRENTLY NOTICEABLE IN THE OBSERVATIONS BEHIND THE
COLD FRONT WHERE CEILINGS UNDER 1K FEET ARE PRESENT. RAP AND NAM
MODEL SOUNDINGS INDICATE THIS MOISTURE STICKING AROUND FOR MUCH OF
THE DAY...SO TRENDED TOWARD A MORE PESSIMISTIC SKY COVER FORECAST
AND HENCE LOWERED MAX TEMPERATURES TODAY BY A FEW DEGREES ACROSS THE
FA. MAX TEMPS WILL BE ABOUT 10 DEGREES BELOW SEASONAL NORMALS FOR
THIS TIME OF YEAR. IN ADDITION...WRAP AROUND LIGHT RAIN SHOWERS ARE
EXPECTED TO MOVE ACROSS THE NORTHERN PORTION OF THE CWA AS THEY
CYCLONIC CIRCULATION ALOFT REMAINS BETTER TOWARD THE NORTH /AS WELL
AS AT LEAST SOME FGEN AND FN VECTOR CONVERGENCE/. SKIES WILL BEGIN
CLEARING LATE THIS AFTERNOON AND MOSTLY CLEAR SKIES ARE EXPECTED
OVERNIGHT...EXCEPT CLOUDS WILL QUICKLY BEGIN FILLING IN FROM THE
SOUTHWEST EARLY SATURDAY MORNING.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 340 AM CDT FRI MAY 9 2014
AN UNSETTLED PERIOD REMAINS FORECAST FOR MUCH OF THE LONGER TERM
AS NORTHERN AND SOUTHERN STREAM ENERGY EVENTUALLY PHASE OVER THE
CENTER OF THE COUNTRY AROUND THE MIDDLE OF NEXT WEEK. THIS PROCESS
OCCURS THE FASTEST WITH THE GFS WHILE DP/DT SHOWS THAT THE SLOWER
ECMWF IS BECOMING EVEN SLOWER WITH TIME.
ON SATURDAY...A WAVE MOVING IN FROM THE CENTRAL PLAINS WILL BRING
THICKENING CLOUDINESS AND SHOWERS BACK ACROSS THE FA FROM SW TO NE
DURING THE DAY. A BRIEF BREAK IN THE PRECIPITATION IS EXPECTED
SATURDAY NIGHT BEFORE A MORE POTENT WAVE BEGINS TO TAKE SHAPE OVER
THE CENTRAL PLAINS ON SUNDAY. THIS WAVE IS BEING DRIVEN BY THE
SOUTHERN STREAM ENERGY. USING THE SLOWER ECWMF...THE LOW IN THE
PLAINS TAKES UNTIL MONDAY EVENING TO ARRIVE IN SE MN. THIS PLACES
MUCH OF THE FA IN LOW LEVEL THETA-E ADVECTION FROM SUNDAY THROUGH
MONDAY...WITH SOUTHERN MN BEARING THE BRUNT OF IT. HENCE...LIKELY
POPS STREAM BACK IN ON SUNDAY FROM THE SOUTHWEST AND PERSIST THROUGH
MONDAY. WIDESPREAD HALF INCH TO ONE INCH RAINFALL IS LIKELY DURING
THIS PERIOD WITH SOME TWO INCH AMOUNTS OVER SOUTHERN MN. THERE WILL
CERTAINLY BE THE THREAT FOR SOME THUNDERSTORMS...ESPECIALLY ON
MONDAY FROM THE TWIN CITIES ON EAST AND SOUTH. STRICTLY USING THE
ECMWF TIMING WOULD INDICATE A WINDOW OF OPPORTUNITY FOR STRONG TO
SEVERE STORMS MONDAY AFTERNOON/EVENING TO THE SOUTH AND EAST OF
THE TWIN CITIES.
THE SHOWERS WILL BEGIN TO TAPER OFF MONDAY NIGHT AS THE LOW
PRESSURE SYSTEM MOVES NORTHEAST OF THE FA. INSTABILITY SHOWERS ARE
POSSIBLE MAINLY FROM CENTRAL MINNESOTA ON NORTHWARD ON TUESDAY.
SCATTERED SHOWERS ARE BACK FOR MUCH OF THE FA WEDNESDAY AND
THURSDAY AS THE UPPER TROUGH COMES TOGETHER FROM THE UPPER
MISSISSIPPI VALLEY TO THE GULF COAST. HIGH TEMPERATURES WILL BE
CLOSE TO NORMAL THIS WEEKEND...BUT THEN RETREAT TO SOME 10 TO 15
DEGREES BELOW NORMAL FOR THE MIDDLE TO END OF NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1248 AM CDT FRI MAY 9 2014
ALL THUNDERSTORM ACTIVITY HAS EXITED THE FORECAST AREA...WITH THE
CONCERN TURNING TO THE IFR AND LIFR CI GS BEING OBSERVED ACROSS
PARTS OF WESTERN AND CENTRAL MINNESOTA AT THIS TIME. THE RAP
ANALYZED CENTER OF THE SURFACE LOW IS ADVANCING NORTHWARD AND IS
NOW POSITIONED OVER THE NORTH METRO. WIDESPREAD FOG HAS DEVELOPED
ACROSS THE REGION WHICH WAS ADDED AT MOST TAF SITES. OVERALL
CHANGES FROM THE PREVIOUS FORECAST INCLUDE A MUCH MORE PESSIMISTIC
COG FORECAST THROUGH THE OVERNIGHT AND THE DAY. LATEST RUNS OF
BOTH THE RAP AND NAM INDICATE SOLID VERY LOW LEVEL MOISTURE ACROSS
THE BOARD ON MODEL SOUNDINGS...AND LASTING LONGER THAN PREVIOUSLY
FORECAST. MOST SITES WILL SEE AT LEAST IFR CI GS THROUGH THE
OVERNIGHT...THEN MVFR OR LOWER THROUGH MOST OF THE DAY. WITH THE
LOW BEING IN THE CENTER OF THE FORECAST AREA...WIND DIRECTION IS
COMPLETELY RELATIVE TO EACH SITES LOCATION RELATIVE THE TO COUNTER
CLOCKWISE CIRCULATION AT THIS TIME...BUT ALL SITES WILL GRADUALLY
SWITCH TO A WESTERLY WIND. WINDS WILL BE STRONG TOMORROW...WITH
GUSTS OVER 20 KNOTS LIKELY. SKIES BEGIN TO CLEAR FRIDAY NIGHT.
KMSP...STARTING THE PERIOD ON THE EDGE OF THE IFR CIGS...AND FOG
HAS ALREADY DEVELOPED AT THE TERMINAL. IFR WILL SET IN THROUGH THE
OVERNIGHT HOURS AND GRADUALLY LIFT DURING THE MORNING. MVFR OR
LOWER CIGS ARE EXPECTED INTO THE AFTERNOON. WINDS WILL SHIFT
SOUTHERLY VERY SOON...THEN TURN WESTERLY.
/OUTLOOK FOR KMSP/
SAT...VFR. CHC -TSRA. WINDS SSE 10KTS.
SUN...MVFR POSSIBLE. LIKELY -SHRA. WINDS SW TO NW 10-15 KTS.
MON...MVFR POSSIBLE. LIKELY -SHRA. WINDS NW 10KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...SPD
LONG TERM...RAH
AVIATION...SPD
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
101 AM CDT FRI MAY 9 2014
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 400 PM CDT THU MAY 8 2014
WIDESPREAD THUNDERSTORMS ONGOING ACROSS THE FORECAST AREA. THE
CURRENT LINE OF STORMS IS THE FIRST OF TWO LINES EXPECTED OVER THE
NEXT SEVERAL HOURS. WIND AND HAIL WILL CONTINUE TO BE A THREAT AND
THE SECOND LINE WILL ALSO HAVE A TORNADO POTENTIAL...ESPECIALLY FOR
STORMS THAT REMAIN NEAR THE WARM FRONT IN SOUTHERN MN.
THERE HAS BEEN MODERATE INCREASES IN SBCAPE AND MLCAPE ALONG AND
SOUTH OF THE I-90 CORRIDOR IN FAR SOUTHERN MN OVER THE PAST 2-3
HOURS WITH THE 1000-1500 J/KG NOW BEING OBSERVED. NORTH OF THE WARM
FRONT THERE REMAINS A SEVERE WIND AND HAIL THREAT. THE WIND THREAT
WAS SOMEWHAT UNEXPECTED DUE TO THE LACK OF SURFACE ROOTED
STORMS...BUT THE FORCING AND INSTABILITY ABOVE THE SURFACE BASED CIN
IS OBVIOUSLY ENOUGH TO OVERCOME AND WE ARE GETTING WINDS OF 40-70
MPH DOWN TO THE SURFACE WITH THE MORE ORGANIZED LINES AND BOWING
SEGMENTS. THIS THREAT SHOULD CONTINUE INTO THE EARLY EVENING FOR
WEST CENTRAL WI ESPECIALLY FOR CONVECTIVE LINES THAT ARE
PERPENDICULAR TO SOUTHWEST TO NORTHEAST ORIENTATED DEEP LAYER SHEAR
VECTORS. DRYING IN THE WATER VAPOR NOW ENTERING FAR SOUTHWEST MN AND
WILL BE THE TRIGGER FOR A SECOND ROUND OF STORMS WITH THE POTENTIAL
FOR HAIL...WINDS AND EVEN TORNADOES ACROSS SOUTHERN MN. THE STRONG
DYNAMIC FORCING WILL CONTINUE TO LIFT THE WARM FRONT...BUT SURFACE
HEATING HAS BEEN LIMITED BY CONVECTIVE DEBRIS AND CLOUD COVER.
NONETHELESS...THE SECOND LINE OF STORMS WILL HAVE HIGHER END
POTENTIAL AND THE ENVIRONMENT IN SOUTH CENTRAL MN WILL SUPPORT
SUPERCELLS BETWEEN 5 PM AND 8 PM. WRAP AROUND SHOWERS WILL BE
POSSIBLE LATE TONIGHT AND EARLY FRIDAY AS THE UPPER LOW SLOWLY MOVES
NORTHEAST OF THE FORECAST AREA.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 400 PM CDT THU MAY 8 2014
THE LONGER TERM CONTINUES TO POSE SIGNIFICANT TIMING AND OVERALL
DEVELOPMENT ISSUES WITH THE WESTERN/CENTRAL CONUS TROUGH DURING THE
PERIOD.
INITIALLY THE GFS AND ECMWF ARE IN FAIR AGREEMENT WITH THE SHORT
WAVE TROUGH MOVING THROUGH SATURDAY INTO SUNDAY. STILL CONSTITUTES
HIGHER CHANCE POPS AT THE MOMENT. AFTER THAT...THE LONGER TERM
MODELS DIVERGE ON TIMING AND DEVELOPMENT OF THE TROUGH OVER THE AREA
INTO NEXT WEEK. THE ECMWF IS MORE AMPLIFIED WITH THE SYSTEM...WITH
NORTHERN AND SOUTHERN STREAMS GRADUALLY MERGING AND LIFTING A FAIRLY
SIGNIFICANT TROUGH/SURFACE LOW NORTHEAST TOWARD THE GREAT LAKES BY
MIDWEEK. THIS COULD INCLUDE THE THREAT OF STRONG/SEVERE STORMS AS
WELL. WILL HAVE TO CONTINUE TO MONITOR MODEL TRENDS WITH THIS
SYSTEM. BOTH MODELS TREND COLDER AIR FILTERING INTO THE NORTHERN
CONUS AS THE TROUGH DIGS SOUTH AND EAST. HIGHS WILL ONLY BE IN THE
50S AND LOWS WILL BE DROPPING INTO THE MIDDLE 30S WHICH WILL
CONTINUE THE THREAT FOR FROST FROM WEDNESDAY INTO THE FOLLOWING
WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1248 AM CDT FRI MAY 9 2014
ALL THUNDERSTORM ACTIVITY HAS EXITED THE FORECAST AREA...WITH THE
CONCERN TURNING TO THE IFR AND LIFR CIGS BEING OBSERVED ACROSS
PARTS OF WESTERN AND CENTRAL MINNESOTA AT THIS TIME. THE RAP
ANALYZED CENTER OF THE SURFACE LOW IS ADVANCING NORTHWARD AND IS
NOW POSITIONED OVER THE NORTH METRO. WIDESPREAD FOG HAS DEVELOPED
ACROSS THE REGION WHICH WAS ADDED AT MOST TAF SITES. OVERALL
CHANGES FROM THE PREVIOUS FORECAST INCLUDE A MUCH MORE PESSIMISTIC
CIG FORECAST THROUGH THE OVERNIGHT AND THE DAY. LATEST RUNS OF
BOTH THE RAP AND NAM INDICATE SOLID VERY LOW LEVEL MOISTURE ACROSS
THE BOARD ON MODEL SOUNDINGS...AND LASTING LONGER THAN PREVIOUSLY
FORECAST. MOST SITES WILL SEE AT LEAST IFR CIGS THROUGH THE
OVERNIGHT...THEN MVFR OR LOWER THROUGH MOST OF THE DAY. WITH THE
LOW BEING IN THE CENTER OF THE FORECAST AREA...WIND DIRECTION IS
COMPLETELY RELATIVE TO EACH SITES LOCATION RELATIVE THE TO COUNTER
CLOCKWISE CIRCULATION AT THIS TIME...BUT ALL SITES WILL GRADUALLY
SWITCH TO A WESTERLY WIND. WINDS WILL BE STRONG TOMORROW...WITH
GUSTS OVER 20 KNOTS LIKELY. SKIES BEGIN TO CLEAR FRIDAY NIGHT.
KMSP...STARTING THE PERIOD ON THE EDGE OF THE IFR CIGS...AND FOG
HAS ALREADY DEVELOPED AT THE TERMINAL. IFR WILL SET IN THROUGH THE
OVERNIGHT HOURS AND GRADUALLY LIFT DURING THE MORNING. MVFR OR
LOWER CIGS ARE EXPECTED INTO THE AFTERNOON. WINDS WILL SHIFT
SOUTHERLY VERY SOON...THEN TURN WESTERLY.
/OUTLOOK FOR KMSP/
SAT...VFR. CHC -TSRA. WINDS SSE 10KTS.
SUN...MVFR POSSIBLE. LIKELY -SHRA. WINDS SW TO NW 10-15 KTS.
MON...MVFR POSSIBLE. LIKELY -SHRA. WINDS NW 10KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...DWE
LONG TERM...DWE
AVIATION...SPD
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
1207 AM CDT Fri May 9 2014
.UPDATE...
Issued at 730 PM CDT THU MAY 8 2014
Surprisingly busy evening. Shield of rain with embedded
convection has proved to be interesting, with some isolated damage
reports with brief bowing/spin up vorts in shallow convective
cells/elements. Low level 0-1km helicity actually fairly stout
over the Mo Ozarks this afternoon/evening. Overall trend of the
eastern cwfa convection is downward and expect that trend to
continue.
Deeper scattered convection is occurring ahead of a cold front over
eastern KS with the most notable updrafts w-nw-n of KCNU. Storms
having a tough time of it, but still seeing a stronger updraft or
two firing up. MLCAPE of around 1000 J/kg is occurring just ahead
of the front, but drops off quite a bit has you head east-se into
MO. 0-6km bulk shear more than adequate for storm organization
where somewhat stronger instability occurs over se KS and far
western MO later this evening. HRRR however, really not doing much
with the existing convection owing to a lack of progged overall
instability. Will watch trends, but the weakening trend of the
HRRR looks good later this evening.
Later tonight, a veering low level jet and moisture advection
should allow some additional elevated convection to develop
overnight into Friday morning ahead of the low level front with
the approach of shortwave/upper jet max.
&&
.SHORT TERM...(This Evening and Tonight)
Issued at 300 PM CDT THU MAY 8 2014
An upper level trough is currently pushing east into the central
Plains as an associated area of surface low pressure pushes
northeast across eastern Nebraska. A cold front ALSO extends south
from the low and is pushing east across central Kansas and
Oklahoma.
Convection is ongoing across the area. This activity formed over
Oklahoma overnight and continues to develop and push to the
northeast. These showers and thunderstorms will continue to track
northeast across the area this afternoon into the early evening
hours. Deep layer shear is on the weak side across the area.
Instability is starting to increase across the eastern Ozarks as
more heating was able to occur in these locations before clouds
were able to overspread the area. The overall severe potential is
on the low side with this activity, but with slightly better
instability there could be a few strong wind gusts with any bow
segments that can develop this afternoon and early this evening.
This activity will push east of the area by the early to mid
evening hours.
The clouds are clearing from west to east across eastern Kansas
into central Oklahoma behind this convection. We will have to see
how far east the clearing can make it this afternoon/early this
evening. The clearing will likely make it over to the far western
portion of the forecast area. Additional thunderstorms are
expected to develop across northeastern Oklahoma into eastern
Kansas along a cold front late this afternoon into this evening.
This activity will then track to the northeast and may clip
southeastern Kansas and far western Missouri. Deep layer wind
shear will begin to increase from west to east this evening and if
enough clearing occurs and enough instability can develop, hail in
excess of quarters will be possible with stronger storms. These storms
may congeal into a line and track east across the area. If the
line does develop winds in excess of 60mph will be possible. There
would also be a small risk for a brief tornado within this line
generally northwest of a Columbus Kansas to Osceola Missouri Line
this evening.
The cold front will then slowly sag southeast towards the area late
this evening into the overnight hours. Showers and thunderstorms
are expected to develop and ride along the front overnight. The
front will push over the far northern and western portions of the
forecast area tonight. Locally heavy rainfall will occur where the
training of storms can occur along the front. Due to the dry
antecedent conditions the overall flood risk is low with this
potential heavy rainfall.
.LONG TERM...(Friday through Thursday)
Issued at 300 PM CDT THU MAY 8 2014
An active weather pattern will continue Friday into early next
week as the a couple storm system track through the region.
Any convection that develops overnight tonight should push east of
the area by Friday morning, with clearing expected behind this
activity. The cold front will continue to track southeast through
the area on Friday. Areas southeast of the front will become
unstable. Better deep layer shear will be over the region on
Friday afternoon allowing organized updrafts. Additional
thunderstorms will develop along the front, and these storms will
have the potential to become strong a severe. The main risk will
be large hail with a few of the strongest storms capable of hail
to golf balls generally along and southeast of the Interstate 44
corridor. The front will push south of the area Friday evening
with dry conditions overnight Friday.
The front will then lift back north across the area Saturday.
Thunderstorms area expected to develop along and north of the
front as it lifts through the region. A few of these storms could
become strong to severe with large hail the main risk. South of the
front instability will increase but there will not be much in a way
of lift, and a cap will be increasing through the day as a warm
air mass in the mid level spreads over the area. So, think all in all
most of the activity will occur along and ahead of the front on
Saturday.
Another upper level system will track through the region late this
weekend into early next week. Medium range models continue to
differ on the track, timing, and strength of this system. The cold
front will sag south then sweep through the region as the upper
level trough approaches and sweeps through the region. Additional
severe storm potential will be possible, but details/evolution of
storms are lacking this far out in time.
Northwest flow aloft pattern will setup over the region behind
this system through the middle of next week behind this system.
Cooler conditions will occur across the region in this northwest
flow pattern.
&&
.AVIATION...(For the 06Z TAFS through 06Z Friday Night)
Issued at 1158 PM CDT THU MAY 8 2014
Scattered showers and thunderstorm will be possible for the
regions terminals through 10z as a cold front moves very slowly to
the east across Kansas. Ceilings will become MVFR across the area
during the overnight hours with slowly improving flight conditions
during the day on Friday.
&&
.SGF WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
UPDATE...DSA
SHORT TERM...Wise
LONG TERM...Wise
AVIATION...Hatch
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1148 PM CDT Thu May 8 2014
.UPDATE:
Issued at 853 PM CDT Thu May 8 2014
A north to south area or band of showers and a few thunderstorms
was moving slowly eastward through east central and southeast MO
and west central and southwest IL. The intensity of the radar
returns have weakened over the St Louis metro area with better
rains both north and south. This precipitation was in a region of
low-mid level warm air advection ahead of a southwest flow
shortwave. This activity will eventually translate east of our
forecast area later this evening, with a break in the
precipitation expected until more showers and storms now across
northwest and west central MO and southeast KS, along and just
ahead of an approaching cold front, shifts into our forecast area
late tonight. The HRRR model also tries to bring some of the
convection now across AR northeastward into southeastern MO late
tonight. Could not rule out isolated hail and strong wind gusts
from the stronger storms late tonight. Mild temperatures should
continue tonight with slight cooling, or cooler temperatures over
the extreme northwestern portion of our forecast area behind the
cold front.
GKS
&&
.SHORT TERM: (Through Late Tonight)
Issued at 256 PM CDT Thu May 8 2014
SHRA/TSRA trends are the primary concern this evening, and are
remaining very difficult to pin down. Early on, N-S band of
showers and thunderstorms now moving into central MO will work its
way east during the remainder of the afternoon and early evening.
Have leaned heavily on the HRRR runs for trends over the next 3-6
hours, as it continues to provide superior guidance on the trends
with this area of convection. Passage of the shortwave fueling
this precip will likely cause area to diminish a bit in coverage
and intensity during the evening, but additional (and hard to
time) upstream shortwaves, as well as persistent WAA and
associated isentropic ascent, should generate additional shower
and thunderstorm activity during the late evening and overnight
hours in the warm sector. Precip threat (especially in our NW
counties) will also be driven by convection that forms along the
cold front and works its way east with time.
Truett
.LONG TERM: (Friday through Next Thursday)
Issued at 256 PM CDT Thu May 8 2014
Overnight elevated SHRA/TSRA forced by the LLJ will probably be
ongoing at daybreak on Fri, at least over part of the CWA. As the
core of the LLJ shifts northeastward into IL/IN, the greatest
moisture convergence and forcing for pcpn will also shift out of
the CWA. Consequently, there should be a decrease in precipitation
coverage or perhaps even a lull during the mid to late morning
hours on Fri. The absence of widespread precipitation combined
with some breaks in the clouds should be sufficient for afternoon
destabilization across the southeastern one-half to one-third of
the CWA. This detail matters because a trough with a vort max in
its base will be approaching from the west. Large scale ascent
from DCVA as well as lift ahead of the cold front will likely
occur in an environment with H7-H5 lapse rates of 6-7.5 deg C/km
and 40-60 kts of 0-6 km bulk shear as well as nearly
unidirectional wind profiles. These parameters are sufficient for
severe thunderstorms with hail and wind as the primary threats.
Although recent model runs all depict a solution where the cold
front moves through most of the CWA on Fri night and then stalls
in southern MO before lifting northward as a warm front on Sat,
the effective boundary might end up much farther south by Sat
morning depending on outflow boundaries from convection on Fri/Fri
night. If this occurs, then the temperature forecast for Sat may
be too warm. Shortwave ridging aloft is expected on Sat with a
compact vort max moving across southern MN, which is much farther
north than yesterday`s model runs. The H85 LLJ associated with the
vort max moving across MN could produce enough lift over the warm
front to support scattered SHRA/TSRA in MO/IL, especially if
forecast H7-H5 lapse rates of 7-8 deg C/km are realized. SHRA/TSRA
are also possible on Sat night due to moisture convergence along a
strengthening southwesterly LLJ.
A new trough develops out west over the weekend, inducing surface
cyclogenesis over the plains and eventually sending another cold
front through MO/IL early next week. Models disagree on how
quickly the trough shifts eastward into the central CONUS, leading
to disagreements on how quickly the cold front moves through the
LSX CWA. It appears that there will be a period of northwest flow
or cyclonic flow during the middle of next week depending on how
the trough evolves. Expect cooler temperatures in such a pattern
with precip chances dependent on shortwaves and moisture
availability.
Kanofsky
&&
.AVIATION: (For the 06z TAFs through 06z Friday Night)
Issued at 1148 PM CDT Thu May 8 2014
Showers have moved out of all of the terminals at the moment, but
there are additional showers and scattered thunderstorms over
western and southern Missouri that are moving toward them. Will
continue with the same timing, though have narrowed the window as
I do not think the rain will last more than 2-3 hours. There are
MVFR ceilings currently at KIRK, and low MVFR ceilings over
southeast Kansas and northeast Oklahoma which I expect to
eventually spread into the terminals later tonight. These ceilings
will eventually dissipate by mid-late morning on Friday. Still
expect a broken line of storms to develop over east central
Missouri around 21Z on Friday afternoon that will move east into
Illinois by 00Z Friday evening. This is reflected by going TAF.
Specifics for KSTL: Showers and scattered thunderstorms currently over
southern and western Missouri will move into the terminal between
09-12Z. Expect this activity to have MVFR conditions associated
with it that will last past when the rain is over. Conditions will
improve by late morning. A broken line of thunderstorms will
develop in the vicinity of KSTL around 21Z on Friday and then move
east into Illinois thereafter.
Britt
&&
.LSX WATCHES/WARNINGS/ADVISORIES:
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS HASTINGS NE
554 PM CDT FRI MAY 9 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 252 PM CDT FRI MAY 9 2014
MAIN FORECAST CONCERNS WILL BE CHANCE FOR SPRINKLES AND LATE TONIGHT
AND INTO SATURDAY MORNING AND TEMPERATURES THROUGH THE PERIOD.
A WEAK SURFACE HIGH PRESSURE SYSTEM IS DRIFTING THROUGH THE CENTRAL
PLAINS TODAY. THIS HAS KEPT SKIES MOSTLY CLEAR AND WINDS FAIRLY
LIGHT AND VARIABLE.
THE SURFACE HIGH IS EXPECTED TO SLIDE TO THE SOUTHEAST LATE THIS
AFTERNOON AND THIS EVENING. WINDS WILL CONTINUE TO TURN TO THE
SOUTHWEST OR WEST THROUGH THE EVENING HOURS. AN UPPER LEVEL WAVE
WILL MOVE INTO THE AREA TONIGHT. SO FAR THE LOWER LAYERS ARE FAIRLY
DRY...BUT BOTH THE GFS AND NAM BRING IN SOME SPOTTY PRECIPITATION
TONIGHT AND THE HRRR AND WRF ALSO HINT AS SOMETHING VERY SPOTTY
ACROSS THE AREA. WITH THE DRY LOWER LEVELS HAVE KEPT A FEW SPRINKLES
MAINLY IN THE NORTHERN PART OF THE FORECAST AREA BECAUSE CONFIDENCE
IS LOW THERE WOULD BE ANYTHING MEASURABLE. A WEAK COLD FRONT WILL
MOVE INTO THE AREA LATE TONIGHT...MOVING THROUGH THE AREA SATURDAY
MORNING. FOR A FEW HOURS BEHIND THE FRONT THERE WILL BE A LITTLE
BREEZIER CONDITIONS...BUT BEFORE MID AFTERNOON THE WINDS START TO
DIMINISH A LITTLE. EVEN BEHIND THE COLD FRONT THE TEMPERATURES ON
SATURDAY WILL BE FAIRLY WARM.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 252 PM CDT FRI MAY 9 2014
GUIDANCE FROM THE NAM...OPERATIONAL GFS AND EC ALL SUGGEST QUASI-
ZONAL UPPER TROPOSPHERIC FLOW WILL EXIST ACROSS MUCH OF THE CONUS AT
00Z SUNDAY...ALTHOUGH A STRENGTHENING UPPER TROPOSPHERIC SHORT WAVE
OVER THE SOUTHWESTERN CONUS WILL BEGIN TURNING THE FLOW OVER OUR
AREA MORE SOUTHWESTERLY BY 12Z SUNDAY. EVENTUALLY AN UPPER
TROPOSPHERIC LONGWAVE TROUGH AXIS IS EXPECTED TO DEVELOP FROM SOUTH
CENTRAL CANADA INTO THE SOUTHWESTERN CONUS BY 00Z MONDAY...WITH THE
TROUGH AXIS EXPECTED TO MOVE EAST ACROSS ACROSS OUR AREA MONDAY
NIGHT INTO TUESDAY...RESULTING IN NORTHWESTERLY UPPER TROPOSPHERIC
FLOW OVER OUR AREA TUESDAY NIGHT ONWARD. AT THE SURFACE AN AREA OF
LOW BAROMETRIC PRESSURE IS EXPECTED ACROSS WESTERN KANSAS AND
EASTERN COLORADO AT 00Z SUNDAY. THIS SURFACE LOW IS EXPECTED TO MOVE
NORTHEAST...LIKELY NEARING NORTHEAST KANSAS BY 00Z MONDAY AND THE
UPPER MISSISSIPPI VALLEY BY 00Z TUESDAY. SO ALTHOUGH THE LOWER
TROPOSPHERIC FLOW ACROSS OUR AREA WILL START THE LONG TERM FORECAST
PERIOD FROM THE EAST/SOUTHEAST...A TRANSITION TO THE NORTHEAST IS
EXPECTED ACROSS MUCH OF THE AREA DURING THE DAY SUNDAY...AND TO
THE NORTHWEST SUNDAY NIGHT THROUGH MUCH OF THE REST OF THE LONG
TERM FORECAST PERIOD.
THE NAM...OPERATIONAL GFS AND EC ALL SUGGEST A 50-60KT JET STREAK
JUST ABOVE THE BOUNDARY LAYER WILL PROMOTE ENOUGH THERMAL ADVECTION
FOR PRECIPITATION PRODUCTION ACROSS MUCH OF THE CWA SATURDAY NIGHT
...ESPECIALLY ACROSS EASTERN PORTIONS OF THE CWA WHERE THERMAL
ADVECTION...AS WELL AS MOISTURE CONVERGENCE...WILL BE ENHANCED.
GIVEN THIS...WENT AHEAD WITH 20-70% POPS ACROSS MUCH OF THE CWA
SATURDAY NIGHT...WITH THE HIGHEST POPS RELEGATED ACROSS OUR EAST. AT
THIS TIME ANY CONVECTION THAT IS REALIZED SATURDAY NIGHT IS EXPECTED
TO REMAIN WEAK.
ANY OVERNIGHT CONVECTION SHOULD DEPART TO THE EAST/NORTHEAST BY
DAYBREAK SUNDAY AS THE LOWER TROPOSPHERIC JET STREAK ALSO SHIFTS TO
THE EAST. THIS MAY ALLOW FOR A BREAK IN PRECIPITATION AT SOME POINT
SUNDAY MORNING...BUT POPS STILL REMAIN INTACT FOR THE ENTIRE CWA ON
SUNDAY AS THERMAL ADVECTION AHEAD OF THE APPROACHING UPPER
TROPOSPHERIC TROUGH INCREASES. AS THE AFOREMENTIONED SURFACE LOW
MOVES INTO NORTHEASTERN KANSAS SUNDAY AFTERNOON AND EVENING...AN
ASSOCIATED LOWER TROPOSPHERIC BAROCLINIC ZONE IS EXPECTED TO BACK
NORTHWEST AS A WARM FRONT...PERHAPS PUSHING INTO OUR EXTREME
EAST/SOUTHEASTERN CWA. LOWER TROPOSPHERIC CONVERGENCE AND RESULTANT
LIFT ALONG THIS BAROCLINIC ZONE...ALONG WITH INCREASING SYNOPTIC-
SCALE OMEGA DUE TO INCREASING UPPER TROPOSPHERIC THERMAL ADVECTION
AHEAD OF THE APPROACHING TROUGH...APPEARS AS THOUGH THEY WILL BE
SUFFICIENT FOR CONVECTIVE INITIATION SUNDAY AFTERNOON AND EVENING.
SOME OF THIS CONVECTION COULD CERTAINLY BE REALIZED OVER OUR
EAST/SOUTHEAST SUNDAY AFTERNOON AND EVENING. THE BAROCLINIC ZONE
SHOULD QUICKLY DEPART OUR AREA TO THE EAST/SOUTHEAST SUNDAY EVENING
AS THE SURFACE LOW MOVES NORTHEAST...THUS ALLOWING A MUCH COOLER AND
DRIER LOWER TROPOSPHERIC AIR MASS INTO THE AREA. THIS WILL RESULT IN
RAPIDLY DECREASING POTENTIAL INSTABILITY THUS ELIMINATING ANY CHANCE
OF DEEP CONVECTION ACROSS OUR AREA. THAT BEING SAID...CONTINUED
THERMAL ADVECTION AHEAD OF THE APPROACHING TROUGH APPEARS IT WILL
STILL BE SUFFICIENT FOR PRECIPITATION PRODUCTION HEADING INTO THE
REMAINDER OF SUNDAY NIGHT AND EVEN MONDAY. AS A RESULT...POPS REMAIN
INTACT ACROSS MUCH OF THE CWA SUNDAY NIGHT INTO MONDAY. BY MONDAY
NIGHT...UPPER TROPOSPHERIC THERMAL ADVECTION SHOULD DIMINISH AS THE
TROUGH AXIS BEGINS CLEARING THE AREA. DRY CONDITIONS ARE CURRENTLY
FORECAST MONDAY NIGHT THROUGH WEDNESDAY AS A RESULT. WEDNESDAY NIGHT
INTO THURSDAY...THERE ARE INDICATIONS FROM THE OPERATIONAL GFS...AND
TO A LESSER EXTENT THE NAM...OF A WEAK UPPER TROPOSPHERIC
PERTURBATION MOVING ACROSS THE REGION AND PERHAPS PROVIDING A PERIOD
OF LIGHT PRECIPITATION. CONFIDENCE REGARDING THIS FEATURE IS NOT
HIGH...BUT ALLBLEND PRESENTED A ~20% POP TO OUR NORTH/NORTHEAST
WEDNESDAY NIGHT INTO THURSDAY AND OPTED TO KEEP THIS POP AS IS.
GUIDANCE SUGGESTS DEW POINT READINGS WELL INTO THE 60S WILL
INFILTRATE MUCH OF EASTERN KANSAS SUNDAY AFTERNOON ON THE WARM SIDE
OF THE BAROCLINIC ZONE. THE MOISTURE CONTENT OF THE LOWER
TROPOSPHERIC AIR MASS IS NOT EXPECTED TO BE NEARLY AS ROBUST FARTHER
NORTHWEST INTO OUR AREA...BUT AGAIN IF THE BAROCLINIC ZONE CAN SNEAK
INTO OUR EAST/SOUTHEAST SUNDAY AFTERNOON AND EVENING...THEN
POTENTIAL INSTABILITY VALUES COULD CERTAINLY CLIMB INTO THE 1000-
2000J/KG RANGE. DEEP LAYER BULK SHEAR VALUES ON THE ORDER OF ~50KTS
ARE ALSO FORECAST ACROSS OUR EAST/SOUTHEAST SUNDAY AFTERNOON AND
EVENING. SO...ALTHOUGH IT APPEARS THE BULK OF THE SEVERE WEATHER
SHOULD REMAIN SOUTH AND EAST OF OUR CWA...IT STILL APPEARS THERE
WILL BE A BRIEF WINDOW OF OPPORTUNITY FOR STRONG THUNDERSTORM
ACTIVITY ACROSS PORTIONS OF OUR CWA...GENERALLY ALONG AND SOUTHEAST
OF A LINE FROM ALMA TO YORK. A THREAT FOR SEVERE WEATHER WILL RESIDE
FARTHER SOUTHEAST...GENERALLY ALONG AND SOUTHEAST OF A LINE FROM
BELOIT TO HEBRON. WILL GO AHEAD AND MENTION THESE THREATS IN THE HWO
FOR SUNDAY.
GUIDANCE ALSO SUGGESTS LOWER TROPOSPHERIC PRESSURE RISES POST-FROPA
COULD PROVIDE A STRONG LOWER TROPOSPHERIC WIND FIELD ACROSS
NORTHWESTERN PORTIONS OF THE CWA SUNDAY AFTERNOON INTO SUNDAY
EVENING. GUIDANCE SUGGESTS A SUSTAINED WIND OF 25-30KTS WITH LOCALLY
HIGHER GUSTS WILL BE REALIZED AND AS A RESULT...WILL MENTION SUCH
CONDITIONS IN THE HWO.
A COOLER LOWER TROPOSPHERIC AIR MASS WILL INFILTRATE THE AREA
FOLLOWING THE PASSAGE OF THE BAROCLINIC ZONE SUNDAY...WITH HIGHS
GENERALLY IN THE 50 ON MONDAY AND IN THE 60S TUESDAY THROUGH FRIDAY.
OVERNIGHT LOWS IN THE 40S ARE FORECAST FOR THE MOST PART THROUGH THE
LONG TERM FORECAST PERIOD.
&&
.AVIATION...(FOR THE 00Z KGRI TAF THROUGH 00Z SATURDAY EVENING)
ISSUED AT 545 PM CDT FRI MAY 9 2014
WIND SHOULD QUICKLY DIMINISH BY THE TIME OF THE BEGINNING OF THE
FORECAST. ONLY HIGH LEVEL CIRRUS IS EXPECTED. HOWEVER...THERE IS A
VERY OUTSIDE SHOT AT A RANDOM THUNDERSHOWER DEVELOPING AROUND
12Z...BUT THIS WOULD BE A BIT MORE LIKELY FARTHER TO THE EAST.
MODELS INDICATE A POTENTIAL BRUSH WITH LOW-LEVEL WIND SHEAR ISSUES
NEAR 06Z...BUT THIS APPEARS TO BE JUST LOW ENOUGH NOT TO INCLUDE
IN THIS FORECAST. WIND SPEED WILL ONCE AGAIN KICK UP BY AFTERNOON
SATURDAY WITH INCREASED LOW-LEVEL LAPSE RATES.
&&
.FIRE WEATHER...
ISSUED AT 252 PM CDT FRI MAY 9 2014
RELATIVE HUMIDITY LEVELS ARE EXPECTED TO DROP BELOW 25 PERCENT FOR
NORTH CENTRAL KANSAS AND FAR SOUTHERN SOUTH CENTRAL NEBRASKA FOR
SATURDAY AFTERNOON. DURING THE MORNING THE WINDS WILL BE WEST OR
NORTHWEST AT 15 TO 20 MPH WITH GUSTS TO AROUND 25 MPH...BUT BY
AFTERNOON...WHEN THE RELATIVE HUMIDITY WILL BE THE LOWEST...THE
WINDS WILL HAVE DIMINISHED TO 10 TO 15 MPH WITH GUSTS TO 20 MPH.
EXPECT THERE TO ONLY BE A SMALL TIME FRAME WHERE NEAR CRITICAL FIRE
DANGER IS EVEN CLOSE. WILL LEAVE IT OUT OF THE HWO AT THIS TIME.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...JCB
LONG TERM...BRYANT
AVIATION...HEINLEIN
FIRE WEATHER...JCB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
320 PM CDT FRI MAY 9 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 252 PM CDT FRI MAY 9 2014
MAIN FORECAST CONCERNS WILL BE CHANCE FOR SPRINKLES AND LATE TONIGHT
AND INTO SATURDAY MORNING AND TEMPERATURES THROUGH THE PERIOD.
A WEAK SURFACE HIGH PRESSURE SYSTEM IS DRIFTING THROUGH THE CENTRAL
PLAINS TODAY. THIS HAS KEPT SKIES MOSTLY CLEAR AND WINDS FAIRLY
LIGHT AND VARIABLE.
THE SURFACE HIGH IS EXPECTED TO SLIDE TO THE SOUTHEAST LATE THIS
AFTERNOON AND THIS EVENING. WINDS WILL CONTINUE TO TURN TO THE
SOUTHWEST OR WEST THROUGH THE EVENING HOURS. AN UPPER LEVEL WAVE
WILL MOVE INTO THE AREA TONIGHT. SO FAR THE LOWER LAYERS ARE FAIRLY
DRY...BUT BOTH THE GFS AND NAM BRING IN SOME SPOTTY PRECIPITATION
TONIGHT AND THE HRRR AND WRF ALSO HINT AS SOMETHING VERY SPOTTY
ACROSS THE AREA. WITH THE DRY LOWER LEVELS HAVE KEPT A FEW SPRINKLES
MAINLY IN THE NORTHERN PART OF THE FORECAST AREA BECAUSE CONFIDENCE
IS LOW THERE WOULD BE ANYTHING MEASURABLE. A WEAK COLD FRONT WILL
MOVE INTO THE AREA LATE TONIGHT...MOVING THROUGH THE AREA SATURDAY
MORNING. FOR A FEW HOURS BEHIND THE FRONT THERE WILL BE A LITTLE
BREEZIER CONDITIONS...BUT BEFORE MID AFTERNOON THE WINDS START TO
DIMINISH A LITTLE. EVEN BEHIND THE COLD FRONT THE TEMPERATURES ON
SATURDAY WILL BE FAIRLY WARM.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 252 PM CDT FRI MAY 9 2014
GUIDANCE FROM THE NAM...OPERATIONAL GFS AND EC ALL SUGGEST QUASI-
ZONAL UPPER TROPOSPHERIC FLOW WILL EXIST ACROSS MUCH OF THE CONUS AT
00Z SUNDAY...ALTHOUGH A STRENGTHENING UPPER TROPOSPHERIC SHORT WAVE
OVER THE SOUTHWESTERN CONUS WILL BEGIN TURNING THE FLOW OVER OUR
AREA MORE SOUTHWESTERLY BY 12Z SUNDAY. EVENTUALLY AN UPPER
TROPOSPHERIC LONGWAVE TROUGH AXIS IS EXPECTED TO DEVELOP FROM SOUTH
CENTRAL CANADA INTO THE SOUTHWESTERN CONUS BY 00Z MONDAY...WITH THE
TROUGH AXIS EXPECTED TO MOVE EAST ACROSS ACROSS OUR AREA MONDAY
NIGHT INTO TUESDAY...RESULTING IN NORTHWESTERLY UPPER TROPOSPHERIC
FLOW OVER OUR AREA TUESDAY NIGHT ONWARD. AT THE SURFACE AN AREA OF
LOW BAROMETRIC PRESSURE IS EXPECTED ACROSS WESTERN KANSAS AND
EASTERN COLORADO AT 00Z SUNDAY. THIS SURFACE LOW IS EXPECTED TO MOVE
NORTHEAST...LIKELY NEARING NORTHEAST KANSAS BY 00Z MONDAY AND THE
UPPER MISSISSIPPI VALLEY BY 00Z TUESDAY. SO ALTHOUGH THE LOWER
TROPOSPHERIC FLOW ACROSS OUR AREA WILL START THE LONG TERM FORECAST
PERIOD FROM THE EAST/SOUTHEAST...A TRANSITION TO THE NORTHEAST IS
EXPECTED ACROSS MUCH OF THE AREA DURING THE DAY SUNDAY...AND TO
THE NORTHWEST SUNDAY NIGHT THROUGH MUCH OF THE REST OF THE LONG
TERM FORECAST PERIOD.
THE NAM...OPERATIONAL GFS AND EC ALL SUGGEST A 50-60KT JET STREAK
JUST ABOVE THE BOUNDARY LAYER WILL PROMOTE ENOUGH THERMAL ADVECTION
FOR PRECIPITATION PRODUCTION ACROSS MUCH OF THE CWA SATURDAY NIGHT
...ESPECIALLY ACROSS EASTERN PORTIONS OF THE CWA WHERE THERMAL
ADVECTION...AS WELL AS MOISTURE CONVERGENCE...WILL BE ENHANCED.
GIVEN THIS...WENT AHEAD WITH 20-70% POPS ACROSS MUCH OF THE CWA
SATURDAY NIGHT...WITH THE HIGHEST POPS RELEGATED ACROSS OUR EAST. AT
THIS TIME ANY CONVECTION THAT IS REALIZED SATURDAY NIGHT IS EXPECTED
TO REMAIN WEAK.
ANY OVERNIGHT CONVECTION SHOULD DEPART TO THE EAST/NORTHEAST BY
DAYBREAK SUNDAY AS THE LOWER TROPOSPHERIC JET STREAK ALSO SHIFTS TO
THE EAST. THIS MAY ALLOW FOR A BREAK IN PRECIPITATION AT SOME POINT
SUNDAY MORNING...BUT POPS STILL REMAIN INTACT FOR THE ENTIRE CWA ON
SUNDAY AS THERMAL ADVECTION AHEAD OF THE APPROACHING UPPER
TROPOSPHERIC TROUGH INCREASES. AS THE AFOREMENTIONED SURFACE LOW
MOVES INTO NORTHEASTERN KANSAS SUNDAY AFTERNOON AND EVENING...AN
ASSOCIATED LOWER TROPOSPHERIC BAROCLINIC ZONE IS EXPECTED TO BACK
NORTHWEST AS A WARM FRONT...PERHAPS PUSHING INTO OUR EXTREME
EAST/SOUTHEASTERN CWA. LOWER TROPOSPHERIC CONVERGENCE AND RESULTANT
LIFT ALONG THIS BAROCLINIC ZONE...ALONG WITH INCREASING SYNOPTIC-
SCALE OMEGA DUE TO INCREASING UPPER TROPOSPHERIC THERMAL ADVECTION
AHEAD OF THE APPROACHING TROUGH...APPEARS AS THOUGH THEY WILL BE
SUFFICIENT FOR CONVECTIVE INITIATION SUNDAY AFTERNOON AND EVENING.
SOME OF THIS CONVECTION COULD CERTAINLY BE REALIZED OVER OUR
EAST/SOUTHEAST SUNDAY AFTERNOON AND EVENING. THE BAROCLINIC ZONE
SHOULD QUICKLY DEPART OUR AREA TO THE EAST/SOUTHEAST SUNDAY EVENING
AS THE SURFACE LOW MOVES NORTHEAST...THUS ALLOWING A MUCH COOLER AND
DRIER LOWER TROPOSPHERIC AIR MASS INTO THE AREA. THIS WILL RESULT IN
RAPIDLY DECREASING POTENTIAL INSTABILITY THUS ELIMINATING ANY CHANCE
OF DEEP CONVECTION ACROSS OUR AREA. THAT BEING SAID...CONTINUED
THERMAL ADVECTION AHEAD OF THE APPROACHING TROUGH APPEARS IT WILL
STILL BE SUFFICIENT FOR PRECIPITATION PRODUCTION HEADING INTO THE
REMAINDER OF SUNDAY NIGHT AND EVEN MONDAY. AS A RESULT...POPS REMAIN
INTACT ACROSS MUCH OF THE CWA SUNDAY NIGHT INTO MONDAY. BY MONDAY
NIGHT...UPPER TROPOSPHERIC THERMAL ADVECTION SHOULD DIMINISH AS THE
TROUGH AXIS BEGINS CLEARING THE AREA. DRY CONDITIONS ARE CURRENTLY
FORECAST MONDAY NIGHT THROUGH WEDNESDAY AS A RESULT. WEDNESDAY NIGHT
INTO THURSDAY...THERE ARE INDICATIONS FROM THE OPERATIONAL GFS...AND
TO A LESSER EXTENT THE NAM...OF A WEAK UPPER TROPOSPHERIC
PERTURBATION MOVING ACROSS THE REGION AND PERHAPS PROVIDING A PERIOD
OF LIGHT PRECIPITATION. CONFIDENCE REGARDING THIS FEATURE IS NOT
HIGH...BUT ALLBLEND PRESENTED A ~20% POP TO OUR NORTH/NORTHEAST
WEDNESDAY NIGHT INTO THURSDAY AND OPTED TO KEEP THIS POP AS IS.
GUIDANCE SUGGESTS DEW POINT READINGS WELL INTO THE 60S WILL
INFILTRATE MUCH OF EASTERN KANSAS SUNDAY AFTERNOON ON THE WARM SIDE
OF THE BAROCLINIC ZONE. THE MOISTURE CONTENT OF THE LOWER
TROPOSPHERIC AIR MASS IS NOT EXPECTED TO BE NEARLY AS ROBUST FARTHER
NORTHWEST INTO OUR AREA...BUT AGAIN IF THE BAROCLINIC ZONE CAN SNEAK
INTO OUR EAST/SOUTHEAST SUNDAY AFTERNOON AND EVENING...THEN
POTENTIAL INSTABILITY VALUES COULD CERTAINLY CLIMB INTO THE 1000-
2000J/KG RANGE. DEEP LAYER BULK SHEAR VALUES ON THE ORDER OF ~50KTS
ARE ALSO FORECAST ACROSS OUR EAST/SOUTHEAST SUNDAY AFTERNOON AND
EVENING. SO...ALTHOUGH IT APPEARS THE BULK OF THE SEVERE WEATHER
SHOULD REMAIN SOUTH AND EAST OF OUR CWA...IT STILL APPEARS THERE
WILL BE A BRIEF WINDOW OF OPPORTUNITY FOR STRONG THUNDERSTORM
ACTIVITY ACROSS PORTIONS OF OUR CWA...GENERALLY ALONG AND SOUTHEAST
OF A LINE FROM ALMA TO YORK. A THREAT FOR SEVERE WEATHER WILL RESIDE
FARTHER SOUTHEAST...GENERALLY ALONG AND SOUTHEAST OF A LINE FROM
BELOIT TO HEBRON. WILL GO AHEAD AND MENTION THESE THREATS IN THE HWO
FOR SUNDAY.
GUIDANCE ALSO SUGGESTS LOWER TROPOSPHERIC PRESSURE RISES POST-FROPA
COULD PROVIDE A STRONG LOWER TROPOSPHERIC WIND FIELD ACROSS
NORTHWESTERN PORTIONS OF THE CWA SUNDAY AFTERNOON INTO SUNDAY
EVENING. GUIDANCE SUGGESTS A SUSTAINED WIND OF 25-30KTS WITH LOCALLY
HIGHER GUSTS WILL BE REALIZED AND AS A RESULT...WILL MENTION SUCH
CONDITIONS IN THE HWO.
A COOLER LOWER TROPOSPHERIC AIR MASS WILL INFILTRATE THE AREA
FOLLOWING THE PASSAGE OF THE BAROCLINIC ZONE SUNDAY...WITH HIGHS
GENERALLY IN THE 50 ON MONDAY AND IN THE 60S TUESDAY THROUGH FRIDAY.
OVERNIGHT LOWS IN THE 40S ARE FORECAST FOR THE MOST PART THROUGH THE
LONG TERM FORECAST PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1215 PM CDT FRI MAY 9 2014
A FEW MID LEVEL CLOUDS WILL MOVE THROUGH THE KGRI TERMINAL AREA
THIS AFTERNOON. FURTHER WEST THERE ARE SOME MID AND HIGH LEVEL
CLOUDS THAT WILL MOVE INTO THE AREA THIS EVENING.
&&
.FIRE WEATHER...
ISSUED AT 252 PM CDT FRI MAY 9 2014
RELATIVE HUMIDITY LEVELS ARE EXPECTED TO DROP BELOW 25 PERCENT FOR
NORTH CENTRAL KANSAS AND FAR SOUTHERN SOUTH CENTRAL NEBRASKA FOR
SATURDAY AFTERNOON. DURING THE MORNING THE WINDS WILL BE WEST OR
NORTHWEST AT 15 TO 20 MPH WITH GUSTS TO AROUND 25 MPH...BUT BY
AFTERNOON...WHEN THE RELATIVE HUMIDITY WILL BE THE LOWEST...THE
WINDS WILL HAVE DIMINISHED TO 10 TO 15 MPH WITH GUSTS TO 20 MPH.
EXPECT THERE TO ONLY BE A SMALL TIME FRAME WHERE NEAR CRITICAL FIRE
DANGER IS EVEN CLOSE. WILL LEAVE IT OUT OF THE HWO AT THIS TIME.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...JCB
LONG TERM...BRYANT
AVIATION...JCB
FIRE WEATHER...JCB
AREA FORECAST DISCUSSION
NWS ELKO NV
1012 AM PDT FRI MAY 9 2014
.SYNOPSIS...SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE
EXPECTED ACROSS NORTHERN NEVADA TODAY. ANOTHER STORM SYSTEM WILL
BRING SHOWERS AND THUNDERSTORMS TO NORTHERN AND CENTRAL NEVADA
SATURDAY. SOME LIGHT SNOW ACCUMULATIONS WILL BE POSSIBLE ABOVE
6000 FT. WARM TEMPERATURES AND NICE WEATHER IS EXPECTED NEXT WEEK.
&&
.UPDATE...ALTHOUGH INSTABILITY IS RATHER WEAK...MID LEVEL LAPSE
RATES WILL STEEPEN THIS AFTERNOON. THIS COMBINED WITH A STRONG
~110 KNOT JET NOSING INTO NORTHERN NEVADA WILL PRODUCE SCATTERED
SHOWERS AND ISOLATED THUNDERSTORMS. HRRR SUPPORTS THIS SOLUTION
AND PROVIDES CONFIDENCE IN THIS FORECAST. ANY SHOWER/ISOLATED
STORM COULD PRODUCE SMALL HAIL...BRIEF HEAVY RAIN...AND GUSTY
WINDS. ACTIVITY WILL DIMINISH AFTER SUNSET.
&&
.PREV DISCUSSION... /ISSUED AT 509 AM /
SYNOPSIS...INTERMITTENT SHOWERS ARE EXPECTED AS ANOTHER LOW
PRESSURE SYSTEM APPROACHES. A STRONG COLD FRONT WILL MOVE THROUGH
THE STATE ON SATURDAY TO BRING THUNDERSTORMS ALONG WITH MORE RAIN
AND SNOW. LOW PRESSURE WILL BE EAST OF THE STATE ON MOTHERS
DAY...HOWEVER LINGERING SHOWERS AND A BRISK NORTH WIND MAY
INTERFERE WITH OUTDOOR PLANS. HIGH PRESSURE WILL BRING DRIER AND
WARMER CONDITIONS TO START THE WORK WEEK.
UPDATE...ADDED ISOLATED THUNDERSTORMS ACROSS NORTHERN ELKO COUNTY
FOR THIS MORNING. A FEW LIGHTNING STRIKES HAVE ALREADY OCCURRED
AND SEEM TO BE ASSOCIATED WITH THE LEFT FRONT QUAD OF A 100 KT
JET CORE MOVING OVER THE NORTHEAST PART OF THE STATE. THE NOSE OF
THIS JET FEATURE WILL PULL TO THE NORTH THIS MORNING.
PREV DISCUSSION... /ISSUED AT 312 AM /
SYNOPSIS...INTERMITTENT SHOWERS ARE EXPECTED AS ANOTHER LOW
PRESSURE SYSTEM APPROACHES. A STRONG COLD FRONT WILL MOVE THROUGH
THE STATE ON SATURDAY TO BRING THUNDERSTORMS ALONG WITH MORE RAIN
AND SNOW. LOW PRESSURE WILL BE EAST OF THE STATE ON MOTHERS
DAY...HOWEVER LINGERING SHOWERS AND A BRISK NORTH WIND MAY
INTERFERE WITH OUTDOOR PLANS. HIGH PRESSURE WILL BRING DRIER AND
WARMER CONDITIONS TO START THE WORK WEEK.
SHORT TERM...TODAY THROUGH SUNDAY. THE MODELS ARE IN VERY GOOD
AGREEMENT THROUGH SUNDAY. A ZONAL FLOW ALOFT IS SPREADING MOISTURE
ACROSS NORTHERN NEVADA AND KEEPING TEMPERATURES ELEVATED...RANGING
FROM THE MID 40S TO AROUND 50 DEGREES AS OF 1 AM PDT. THIS QUASI-
ZONAL FLOW AHEAD OF ANOTHER LOW PRESSURE SYSTEM WILL KEEP
UNSETTLED WEATHER GOING ACROSS PRIMARILY NORTHERN NEVADA THROUGH
TONIGHT. A RAPIDLY MOVING LOW PRESSURE SYSTEM WILL DROP SOUTH FROM
WASHINGTON STATE SATURDAY MORNING TO RE-CENTER OVER NORTHERN
NEVADA BY LATE SATURDAY NIGHT. THE SPEED OF THIS SYSTEM WILL
TRIGGER A STRONG COLD FRONT TO DEVELOP OVER THE GREAT BASIN EARLY
SATURDAY MORNING AND THUNDERSTORM ACTIVITY IS LIKELY TO BEGIN
EARLY AS WELL. SNOW LEVELS WILL DROP QUICKLY TO VALLEY FLOORS
SATURDAY ALONG THE DEVELOPING COLD FRONT. PASSES ALONG INTERSTATE 80
COULD RECEIVE A QUICK 2 INCH SNOW DEPOSIT. HOWEVER COMING OFF OF A
NIGHT WITH ABOVE-FREEZING TEMPERATURES IN MANY AREAS...ELEVATED
ROAD TEMPERATURES SHOULD BLUNT THE IMPACT. GUSTY WESTERLY WINDS
WILL BE INCREASING SATURDAY ASSOCIATED WITH THE FRONT HOWEVER
WIDESPREAD WIND ADVISORY CRITERIA IS NOT EXPECTED. SHOWERS WILL CONTINUE
ACROSS EASTERN NEVADA THROUGH SUNDAY EVENING AS THIS LOW PRESSURE
SYSTEM...LIKE THE LAST...SLOWLY EXITS THE GREAT BASIN. MOUNTAINS
OVER SOUTHEAST WHITE PINE COUNTY COULD SEE SEVERAL INCHES OF NEW
SNOW SATURDAY THROUGH SUNDAY. STRONG NORTHERLY WINDS ARE EXPECTED
ON MOTHERS DAY BEHIND THE EXITING LOW AS WELL. AT THIS
TIME...AREAS SOUTH OF HIGHWAY 50 ARE MODELED TO BE PRONE TO WIND
GUSTS TO AROUND 50 MPH.
HIGH TEMPERATURES WILL RANGE FROM THE MID 50S TO THE MID 60S
TODAY...AND ABOUT 10 DEGREES COOLER SATURDAY...REBOUNDING ON
SUNDAY. LOW TEMPERATURES WILL GENERALLY FALL INTO THE 30S
TONIGHT...AND INTO THE 20S IN MANY LOCATIONS SATURDAY NIGHT BEHIND
THE COLD FRONT.
LONG TERM...SUNDAY NIGHT THROUGH NEXT FRIDAY. THE SYNOPTIC PATTERN
WILL TRANSITION FROM BROAD CYCLONIC FLOW TO HIGH AMPLITUDE RIDGING
OVER THE WESTERN US. BY 12Z MONDAY...THE GFS HAS THE 570 DAM
BISECTING THE SILVER STATE FROM MCDERMITT TO TONOPAH...AND THE ECMWF
HAS THE 570 DAM NORTH OF MONTELLO AT 12Z ON MONDAY. FAST FORWARD 48
HRS...THE RIDGE BUILDS AND THE 582 DAM WILL SURGE INTO NORTHERN NV.
WITH WIDESPREAD SUBSIDENCE ON DECK...EXPECTING A WARMING AND DRYING
TREND. THE NCEP RMOP IS WELL INTO CONFIDENT TERRITORY WITH THE
RIDGE...AND EXPECTING POSITIVE HEIGHT ANOMALIES THE ENTIRE FORECAST
PERIOD. HIGH CONFIDENCE FORECAST. THE RETURN INTERVAL ON THE NAEFS
FOR TEMPS IS PINGING INTO A 30 YEAR EVENT ACROSS THE WEST...WITH A 5
TO 10 YEAR EVENT FOR SLP OVER THE LKN CWA. EXPECT AFTERNOON TEMPS IN
THE 70S ACROSS MOST POPULAR DESTINATIONS IN NE NV...WHILE MORE
REMOTE LOCALES AT SLIGHTLY LOWER ELEVATIONS SUCH AS GABBS AND THE
BLACK ROCK DESERT CAN EXPECT AFTERNOON TEMPERATURES IN THE 80S.
AVIATION...THE RADAR FOR NORTHEASTERN NV INDICATES ISOLATED TO
SCATTERED SHOWERS NORTH OF KWMC AND KEKO. BEST CHANCE OF
PRECIPITATION WILL BE AT KEKO THIS MORNING. GENERALLY EXPECTING CIGS
BETWEEN 050 AND 100...ALONG WITH OBSCURED MT TOPS. SLIGHT CHANCE FOR
PRECIP AT KELY...KEPT VCSH IN THE TAF AT KELY...NO PRECIP EXPECTED AT
KTPH FOR THE ENSUING 24 HR PERIOD.
&&
.LKN WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
94/99
AREA FORECAST DISCUSSION
NWS BISMARCK ND
940 PM CDT SAT MAY 10 2014
.UPDATE...
ISSUED AT 933 PM CDT SAT MAY 10 2014
LARGE PRECIPITATION REGION ON RADAR ALONG AND NORTH OF OCCLUDED
FRONTAL BOUNDARY ACROSS SOUTHEAST NORTH DAKOTA. UPLIFT OVER THE
FRONT AIDING IN GENERATING SCATTERED THUNDERSTORMS ACROSS THE
JAMES RIVER VALLEY. RAISED POPS ACROSS THE EAST THROUGH NORTH
CENTRAL. THIS AREA WILL PIVOT NORTH AND WEST THEN DIMINISH SUNDAY.
UPDATE ISSUED AT 657 PM CDT SAT MAY 10 2014
AS OF 630 PM CDT THUNDERSTORMS HAVE ENDED OVER THE NORTHWEST. NOW
THE FOCUS WILL BE ON THE WEAK LINE OF THUNDERSTORMS MOVING UP THE
JAMES RIVER VALLEY. THESE STORMS HAVE FORMED NORTH OF THE
OCCLUDED FRONT IN SOUTHEAST NORTH DAKOTA. EXPECT THESE TO BE
ACTIVE FOR A FEW HOURS BUT ALREADY SHOWING SIGNS OF DIMINISHING AS
THEY MOVE AWAY FROM THE BETTER CAPE/MID LEVEL LAPSE RATES ACROSS
THE FAR SOUTHEAST.
UPDATE ISSUED AT 350 PM CDT SAT MAY 10 2014
ADDED THIS UPDATE FOR SCATTERED TO ISOLATED THUNDERSTORMS
NORTHWEST REMAINDER OF THIS AFTERNOON.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 233 PM CDT SAT MAY 10 2014
THE MAIN FORECAST ISSUES IN THE SHORT TERM PERIOD ARE PRECIPITATION
TRENDS AND AMOUNTS TONIGHT THROUGH SUNDAY.
IN THE NEAR TERM...SHOWERS ARE MOST WIDESPREAD ACROSS THE JAMES
RIVER VALLEY...THEN STRETCHING WEST ALONG THE I-94 CORRIDOR INTO
THE SOUTHWEST COUNTIES. THE MODEL CONSENSUS...INCLUDING THE HIGH
RESOLUTION HRRR AND WRF...INDICATE THE FOCUS OF THE HEAVIER RAIN
WILL SHIFT INTO THE NORTHWEST AND NORTH CENTRAL COUNTIES LATER
TONIGHT INTO SUNDAY MORNING. LINGERING SHOWERS ARE POSSIBLE ACROSS
THE EAST SUNDAY AFTERNOON. ELEVATED INSTABILITY FAVORS ISOLATED LATE
AFTERNOON/EVENING THUNDERSTORMS MAINLY EAST OF BISMARCK INTO THE
JAMES RIVER VALLEY...BUT NO SEVERE WEATHER IS EXPECTED. FOR
SUNDAY...EXPECT A CHILLY AND RAW DAY...WITH HIGHS IN THE UPPER 40S
TO UPPER 50S...ABOUT 10-15 DEGREES BELOW NORMAL. A NORTHWEST WIND
WILL BE SUSTAINED AT 20 TO 25 MPH AND MAY FLIRT WITH ADVISORY
CRITERIA ACROSS THE FAR SOUTHWEST.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 233 PM CDT SAT MAY 10 2014
AN SEMI-ACTIVE AND COOL WEATHER PATTERN WILL BE THE MAIN STORY
THROUGH THE LONG TERM FORECAST PERIOD.
UPPER LEVEL TROUGH OVER THE ROCKIES WILL MOVE SLOWLY EAST INTO
THE CENTRAL CONUS SUNDAY NIGHT INTO MONDAY...THEN OFF TO OUR EAST
TUESDAY FOLLOWED BY A QUASI-ACTIVE NORTHWEST FLOW PATTERN FOR THE
REST OF THE WORK WEEK.
FOR SUNDAY NIGHT-MONDAY...SUBSIDENCE ACROSS THE WESTERN HALF OF
THE STATE WILL DRY THINGS OUT WITH LINGERING MOISTURE EAST ALONG
THE UPPER TROUGH. WITH THE TROUGH SLOW TO MOVE EAST...DIURNALLY
DRIVEN SHOWERS WILL BE POSSIBLE BOTH MONDAY AND TUESDAY. MAY BE
COLD ENOUGH DURING THE OVERNIGHT/MORNING PERIODS FOR A RAIN/SNOW
MIX SOME LOCATIONS.
NORTHWEST FLOW WED-FRI WITH POSSIBLE EMBEDDED WAVES AND THE UPPER
JET ALOFT CONTINUING THE THREAT FOR PERIODS OF LIGHT PRECIPITATION.
TEMPERATURES COOL (HIGHS 40S/50S AND LOWS 30S) THROUGH MID
WEEK...WITH A MODERATION IN TEMPERATURES TOWARDS NEXT WEEKEND.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 933 PM CDT SAT MAY 10 2014
SURFACE LOW PRESSURE ACROSS SOUTHEAST NORTH DAKOTA WITH AN
ASSOCIATED FRONTAL SYSTEM EXTENDING EAST FROM THE LOW WILL BE
THE FOCUS FOR SCATTERED THUNDERSTORMS THROUGH MIDNIGHT ACROSS THE
JAMES RIVER VALLEY...INCLUDING KJMS. OTHERWISE THE LOW WILL SPREAD
SHOWERS ACROSS WESTERN AND NORTHERN NORTH DAKOTA TONIGHT. HAZARDS
TO AVIATION ARE SCATTERED TO ISOLATED THUNDERSTORMS FROM KJMS-KMOT
THROUGH 07Z...AND MVFR LOWERING TO IFR CEILINGS AFTER 08Z.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
LONG TERM...NH
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
705 PM CDT SAT MAY 10 2014
.UPDATE...
ISSUED AT 657 PM CDT SAT MAY 10 2014
AS OF 630 PM CDT THUNDERSTORMS HAVE ENDED OVER THE NORTHWEST. NOW
THE FOCUS WILL BE ON THE WEAK LINE OF THUNDERSTORMS MOVING UP THE
JAMES RIVER VALLEY. THESE STORMS HAVE FORMED NORTH OF THE
OCCLUDED FRONT IN SOUTHEAST NORTH DAKOTA. EXPECT THESE TO BE
ACTIVE FOR A FEW HOURS BUT ALREADY SHOWING SIGNS OF DIMINISHING AS
THEY MOVE AWAY FROM THE BETTER CAPE/MID LEVEL LAPSE RATES ACROSS
THE FAR SOUTHEAST.
UPDATE ISSUED AT 350 PM CDT SAT MAY 10 2014
ADDED THIS UPDATE FOR SCATTERED TO ISOLATED THUNDERSTORMS
NORTHWEST REMAINDER OF THIS AFTERNOON.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 233 PM CDT SAT MAY 10 2014
THE MAIN FORECAST ISSUES IN THE SHORT TERM PERIOD ARE PRECIPITATION
TRENDS AND AMOUNTS TONIGHT THROUGH SUNDAY.
IN THE NEAR TERM...SHOWERS ARE MOST WIDESPREAD ACROSS THE JAMES
RIVER VALLEY...THEN STRETCHING WEST ALONG THE I-94 CORRIDOR INTO
THE SOUTHWEST COUNTIES. THE MODEL CONSENSUS...INCLUDING THE HIGH
RESOLUTION HRRR AND WRF...INDICATE THE FOCUS OF THE HEAVIER RAIN
WILL SHIFT INTO THE NORTHWEST AND NORTH CENTRAL COUNTIES LATER
TONIGHT INTO SUNDAY MORNING. LINGERING SHOWERS ARE POSSIBLE ACROSS
THE EAST SUNDAY AFTERNOON. ELEVATED INSTABILITY FAVORS ISOLATED LATE
AFTERNOON/EVENING THUNDERSTORMS MAINLY EAST OF BISMARCK INTO THE
JAMES RIVER VALLEY...BUT NO SEVERE WEATHER IS EXPECTED. FOR
SUNDAY...EXPECT A CHILLY AND RAW DAY...WITH HIGHS IN THE UPPER 40S
TO UPPER 50S...ABOUT 10-15 DEGREES BELOW NORMAL. A NORTHWEST WIND
WILL BE SUSTAINED AT 20 TO 25 MPH AND MAY FLIRT WITH ADVISORY
CRITERIA ACROSS THE FAR SOUTHWEST.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 233 PM CDT SAT MAY 10 2014
AN SEMI-ACTIVE AND COOL WEATHER PATTERN WILL BE THE MAIN STORY
THROUGH THE LONG TERM FORECAST PERIOD.
UPPER LEVEL TROUGH OVER THE ROCKIES WILL MOVE SLOWLY EAST INTO
THE CENTRAL CONUS SUNDAY NIGHT INTO MONDAY...THEN OFF TO OUR EAST
TUESDAY FOLLOWED BY A QUASI-ACTIVE NORTHWEST FLOW PATTERN FOR THE
REST OF THE WORK WEEK.
FOR SUNDAY NIGHT-MONDAY...SUBSIDENCE ACROSS THE WESTERN HALF OF
THE STATE WILL DRY THINGS OUT WITH LINGERING MOISTURE EAST ALONG
THE UPPER TROUGH. WITH THE TROUGH SLOW TO MOVE EAST...DIURNALLY
DRIVEN SHOWERS WILL BE POSSIBLE BOTH MONDAY AND TUESDAY. MAY BE
COLD ENOUGH DURING THE OVERNIGHT/MORNING PERIODS FOR A RAIN/SNOW
MIX SOME LOCATIONS.
NORTHWEST FLOW WED-FRI WITH POSSIBLE EMBEDDED WAVES AND THE UPPER
JET ALOFT CONTINUING THE THREAT FOR PERIODS OF LIGHT PRECIPITATION.
TEMPERATURES COOL (HIGHS 40S/50S AND LOWS 30S) THROUGH MID
WEEK...WITH A MODERATION IN TEMPERATURES TOWARDS NEXT WEEKEND.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 657 PM CDT SAT MAY 10 2014
SURFACE LOW PRESSURE ACROSS SOUTH CENTRAL NORTH DAKOTA WITH AN
ASSOCIATED FRONTAL SYSTEM EXTENDED ACROSS FAR SOUTHEAST NORTH
DAKOTA WILL BE THE FOCUS FOR SCATTERED THUNDERSTORMS THROUGH THE
EVENING ACROSS THE JAMES RIVER VALLEY...INCLUDING KJMS. OTHERWISE
THE LOW WILL SPREAD SHOWERS ACROSS WESTERN AND NORTHERN NORTH
DAKOTA TONIGHT. HAZARDS TO AVIATION ARE SCATTERED TO ISOLATED
THUNDERSTORMS FROM KJMS-KMOT THROUGH 06Z...AND LOW VFR BECOMING
MVFR AFTER 03Z...THEN LOWERING TO IFR CEILINGS AFTER 08Z.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...WAA
LONG TERM...NH
AVIATION...WAA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
256 PM CDT FRI MAY 9 2014
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 255 PM CDT FRI MAY 9 2014
THE MAIN FORECAST ISSUE IN THE SHORT TERM PERIOD WILL BE
PRECIPITATION CHANCES TONIGHT AND SATURDAY. ECMWF HAS BEEN THE
MOST CONSISTENT OF THE DETERMINISTIC MODELS AND WILL USE FOR
PRECIPITATION DETAILS.
CURRENTLY...SUNNY SKIES ACROSS WESTERN AND CENTRAL NORTH DAKOTA
WITH INCREASING CLOUDS MOVING FROM CENTRAL INTO EASTERN MONTANA.
TEMPERATURES ARE RANGING FROM THE MID 50S TO LOWER 60S ACROSS THE
STATE.
FOR TONIGHT...MODELS HAVE BEEN TRENDING A LITTLE SLOWER WITH THE
INITIAL PRECIPITATION MOVING INTO WESTERN NORTH DAKOTA TONIGHT AND
HAVE ADJUSTED POPS ACCORDINGLY. IN ADDITION...WITH THE SLOWER
MOVEMENT...LATEST 17 UTC HRRR AND 18 UTC RAP ARE INDICATING BEST
MOISTURE AND INSTABILITY NOT MAKING IT INTO WESTERN NORTH DAKOTA
UNTIL AROUND MIDNIGHT...OR AFTER. BY THIS TIME THINK THE
POSSIBILITY OF CONVECTION WILL BE MINIMAL SO WILL LEAVE OUT THE
MENTION OF THUNDER.
SATURDAY...A SPLIT UPPER LEVEL TROUGH TAKES SHAPE OVER THE WESTERN
U.S. WITH LEAD SHORTWAVE ENERGY FROM THE SOUTHERN WAVE EJECTING
INTO THE DAKOTAS. WITH AN ASSOCIATED SURFACE LOW LIFTING FROM
SOUTH DAKOTA INTO CENTRAL NORTH DAKOTA. PRECIPITATION CHANCES
WILL SPREAD SOUTHWEST TO NORTHEAST ACROSS THE CWA DURING THE DAY.
THERE MAY BE A BRIEF OPPORTUNITY FOR CONVECTION NEAR THE SURFACE
LOW AND ON THE BACK EDGE OF PRECIPITATION SHIELD IN THE SOUTH CENTRAL
SATURDAY AFTERNOON.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 255 PM CDT FRI MAY 9 2014
AN ACTIVE AND COOL WEATHER PATTERN WILL BE THE MAIN STORY THROUGH
THE LONG TERM FORECAST PERIOD.
UPPER LOW/TROUGH OVER THE PACIFIC NORTHWEST DIGS ACROSS THE
WESTERN CONUS INTO SATURDAY...MOVING OVER THE ROCKIES SUNDAY. 12Z
MODELS HAVE COME INTO MUCH BETTER AGREEMENT WITH THE TROUGH
LINGERING ACROSS THE NORTHERN PLAINS INTO TUESDAY...FOLLOWED BY AN
ACTIVE NORTHWEST FLOW PATTERN FOR THE REST OF THE WORK WEEK.
WILL MAINTAIN CHANCES FOR PRECIPITATION THROUGH MUCH OF THE
PERIOD ALONG WITH CONTINUED COOL/BELOW AVERAGE TEMPERATURES.
FOR SATURDAY NIGHT-SUNDAY...EMBEDDED UPPER LEVEL LOW LIFTS SLOWLY
NORTH ACROSS THE DAKOTAS...PUTTING BEST PRECIP CHANCES NORTH AND
WRAP AROUND MOISTURE WEST. MIX OF RAIN/SNOW POSSIBLE WEST SUNDAY
MORNING AS COLDER AIR IS PULLED SOUTH FROM CANADA. SHOWERS
CONTINUE EAST AND NORTH DURING THE DAY SUNDAY ALONG WITH
INCREASING NORTHWESTERLY WINDS FROM WEST TO EAST BEHIND A SFC LOW.
SUBSIDENCE ACROSS THE WESTERN HALF OF THE STATE SUNDAY NIGHT
SHOULD DRY THINGS OUT WITH LINGERING MOISTURE EAST ALONG THE UPPER
TROUGH. WITH THE TROUGH SLOW TO MOVE EAST...DIURNALLY DRIVEN
SHOWERS WILL BE POSSIBLE BOTH MONDAY AND TUESDAY. MAY BE COLD
ENOUGH DURING THE OVERNIGHT/MORNING PERIODS FOR A RAIN/SNOW MIX
SOME LOCATIONS.
NORTHWEST FLOW WED-FRI WITH POSSIBLE EMBEDDED WAVES AND THE UPPER
JET ALOFT CONTINUING THE THREAT FOR PRECIPITATION.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 255 PM CDT FRI MAY 9 2014
HIGH PRESSURE OVER CENTRAL NORTH DAKOTA WILL MOVE EAST AS LOW
PRESSURE MOVES THROUGH EASTERN MONTANA. CLEAR SKIES TO START THE
TAF PERIOD. POSSIBLE A FEW CUMULUS CLOUDS DURING THE AFTERNOON
WITH INCREASING HIGH LEVEL CLOUDINESS WEST BY LATE AFTERNOON.
CLOUDS WILL INCREASE WITH LOWERING CEILINGS FROM WEST TO EAST
TONIGHT AND SATURDAY. SHOWERS WILL BECOME LIKELY AT KDIK SATURDAY
MORNING AND HAVE ADDED SHRA WITH A LOW VFR CEILING BEGINNING AT 15
UTC. INCREASING SHOWER CHANCES AT KISN AND KBIS BY THE END OF THE
TAF PERIOD BUT WILL LEAVE OUT OF THE TAF FOR NOW...WITH BETTER
CHANCES AFTER 18 UTC.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...TWH
LONG TERM...NH
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
102 AM CDT FRI MAY 9 2014
.UPDATE...
ISSUED AT 1259 AM CDT FRI MAY 9 2014
TRIMMED POPS SLIGHTLY ACROSS THE SOUTHEAST AS RADAR RETURNS ARE
DIMINISHING QUICKLY IN THE AREA. OTHERWISE CURRENT FORECAST LOOKS
TO BE ON TRACK.
UPDATE ISSUED AT 948 PM CDT THU MAY 8 2014
RAIN EXITING THE CENTRAL SECTION OF THE STATE AND NOW PRIMARILY
IN THE JAMES RIVER VALLEY. TRIMMED POPS CENTRAL. OTHERWISE SO FAR
CURRENT FORECAST LOOKS GOOD.
UPDATE ISSUED AT 655 PM CDT THU MAY 8 2014
AT 630 PM CDT...SATELLITE LOOPS SHOW HIGH CLOUDS SPREADING OVER
SOUTHWEST NORTH DAKOTA REPOPULATING THE CLEAR AREA. H300 CLOSED
LOW ON THE RAP MODEL SUGGESTS CIRCULATION AROUND THIS FEATURE IN
NORTHEAST WYOMING LIKELY HELPING TO SPREAD THESE HIGH CLOUDS OVER
SOUTHWEST ND. MEANWHILE...H500 LOW MIGRATING THROUGH NORTHEAST SOUTH
DAKOTA INTO SOUTHEAST NORTH DAKOTA. LIKE THE CURRENT POPS AND WILL
NOT CHANGE AT THIS TIME. MAINLY CLOUDS. MAY BE ABLE TO DROP POPS
CENTRAL AFTER 9 PM.
&&
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 339 PM CDT THU MAY 8 2014
RAINFALL ENDING THIS EVENING AND A DRY FRIDAY WILL HIGHLIGHT THE
SHORT TERM.
RAINFALL THE REMAINDER OF THE AFTERNOON IS EXPECTED TO REMAIN
ALONG AND EAST OF A LINE FROM SELFRIDGE...THROUGH BISMARCK AND
HARVEY...SLOWLY DECREASING FROM WEST TO EAST. BASED UPON THE 17-19
UTC RAP/HRRR...RAIN SHOULD FINALLY END ACROSS THE JAMES RIVER
VALLEY BY 06-07 UTC. OTHERWISE FOR TONIGHT...A WEAK SURFACE RIDGE
AXIS WILL BE IN PLACE ACROSS WESTERN AND CENTRAL NORTH DAKOTA.
GIVEN CLEAR SKIES...LIGHT WINDS AND DEW POINTS IN THE UPPER TEENS
AND 20S...WIDESPREAD OVERNIGHT LOWS IN THE 20S ARE FORECAST OUTSIDE
OF THE JAMES RIVER VALLEY WHERE GREATER CLOUD COVER AND MOISTURE
WILL KEEP LOWS IN THE 30S. LEFT THE MENTION OF FOG OUT FOR NOW DUE
TO DECEASING LOW LEVEL MOISTURE PROFILES WITH HEIGHT AND THE
GREATER LIKELIHOOD OF FROST COMPARED TO FOG. FRIDAY WILL BE CLEAR
AND DRY WITH HIGHS IN THE 60S WITH SOUTHERLY FLOW AHEAD OF THE
SURFACE LOW ACROSS EASTERN MONTANA.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 339 PM CDT THU MAY 8 2014
AN ACTIVE AND COOL WEATHER PATTERN DEVELOPS FOR THE UPCOMING
WEEKEND. UNCERTAINTY INCREASES AFTERWARDS WHEN COMPARING THE
LATEST FEW RUNS OF THE GFS AND ECMWF.
UPPER LOW/TROUGH OVER THE PACIFIC NORTHWEST DIGS ACROSS THE
WESTERN CONUS FRIDAY NIGHT INTO SATURDAY...MOVING OVER THE ROCKIES
SUNDAY. 12Z GFS IS MORE PROGRESSIVE AND MOVES THE TROUGH EAST BY
MONDAY NIGHT...WHILE THE 00Z/12Z ECMWF LINGERS THE TROUGH THROUGH
TUESDAY. NORTHWEST FLOW IS ADVERTISED BY BOTH MODELS BEHIND THE
TROUGH...LIKELY ACTIVE WITH EMBEDDED WAVES MOVING THROUGH THE
REGION.
BASICALLY HAVE CHANCES FOR PRECIPITATION THROUGH THE PERIOD ALONG
WITH CONTINUED COOL/BELOW AVERAGE TEMPERATURES. BEST CHANCES FOR
PRECIPITATION WILL BE OVER THE WEEKEND AS SFC LOW PRESSURE AND LEAD
WAVES MOVE ACROSS THE DAKOTAS. MIX OF RAIN/SNOW POSSIBLE WEST
SUNDAY MORNING AS COLDER AIR IS PULLED SOUTH FROM CANADA.
ADDITIONAL SNOW POSSIBLE EARLY NEXT WEEK IF THE EUROPEAN`S
SOLUTION IS CORRECT WITH A SLOWER EASTWARD PROGRESSION ALLOWING
FOR ANOTHER SHOT OF COLD AIR INTO THE REGION.
MODELS PORTRAY NO INDICATION OUR COOL AND WET PATTERN WILL CHANGE
THROUGH AT LEAST MID-MAY...AND POSSIBLY NOT UNTIL AFTER THE THIRD
WEEK OF MAY AT THE EARLIEST.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1259 AM CDT FRI MAY 9 2014
VFR CONDITIONS EXPECTED ACROSS ALL TERMINALS THROUGH THE 06 UTC TAF
PERIOD. MID CLOUD DECK WILL MOVE EAST OF KJMS AROUND 12 UTC
TONIGHT. WINDS WILL MAINLY BE LIGHT AND VARIABLE TONIGHT...EXCEPT
AT KJMS...AND GRADUALLY BECOME SOUTHERLY THROUGH THE DAY FRIDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...MM
SHORT TERM...AYD
LONG TERM...NH
AVIATION...MM
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
448 PM EDT FRI MAY 9 2014
.SYNOPSIS...
A SLOW MOVING COLD FRONT WILL BRING A CHANCE OF SHOWERS AND
THUNDERSTORMS TONIGHT INTO SATURDAY. A DISTURBANCE BEHIND THE
FRONT WILL PROVIDE A CHANCE FOR MORE THUNDERSTORMS ON SUNDAY.
UNSETTLED WEATHER WILL CONTINUE INTO THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
SCATTERED SHOWERS CONTINUE TO AFFECT PORTIONS OF THE FA THIS AFTN.
THE BEST COVERAGE IS ACROSS THE SE COUNTIES ATTM. HRRR MODEL RUNS
HAVE BEEN HANDLING THE CONVECTION BEST THIS AFTN AND LEANED
TOWARDS ITS SOLUTION FOR THE EVENING INTO OVERNIGHT HOURS. EXPECT
SCATTERED CONVECTION TO CONTINUE TO PERCOLATE ACROSS THE NW
COUNTIES WHILE THE PCPN IN THE SE LIFTS NE ACROSS THE LOWER SCIOTO
VALLEY INTO THE HOCKING HILLS BEFORE PULLING E. THEN CONVECTION
OUT OVER THE LOWER OHIO VALLEY WILL BEGIN TO WORK IN TOWARDS
MIDNIGHT. COVERAGE SHOULD BE BEST ACROSS THE SOUTH...BUT CANT KEEP
THE N DRY. SFC BASED INSTABILITY WILL BEGIN TO WEAKEN WITH
SUNSET...SO EXPECT THE STRENGTH OF THE STORMS TO BE WEAKENING
ALSO. FEEL THE THREAT OF SEVERE WEATHER TONIGHT IS PRETTY LOW.
THE CDFNT WILL WORK INTO THE NW PORTION OF THE FA LATE TONIGHT
BRINGING AN END TO THE PCPN CHANCES THERE.
CLOUD COVER AND PCPN WILL HELP KEEP TEMPERATURES UP TONIGHT. THE
MAJORITY OF THE FA WILL SEE LOWS IN THE LOWER 60S...THE EXCEPTION
BEING THE EXTREME NW COUNTIES WHERE UPPER 50S ARE FORECAST BEHIND
THE FRONT.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
THE MODELS HAVE FLIP-FLOPPED FROM YESTERDAYS PROGRESSIVE
CDFNT...BACK TO A SLOWER MORE SLUGGISH SOLUTION. H5 ENERGY
EJECTING OUT IN A BROAD SW FLOW WILL INTERACT THE CDFNT AND LOW
LEVEL MOISTURE TO PRODUCE SHOWERS AND THUNDERSTORMS SATURDAY. BEST
COVERAGE WILL BE IN THE S AND E AHEAD OF THE FRONT.
THE FRONT SAGS SOUTH THE OHIO RIVER SATURDAY AFTERNOON INTO
SATURDAY NIGHT...ALLOWING SLIGHTLY DRIER AIR TO FILTER IN. A
MOSTLY ZONAL H5 FLOW WILL ALLOW MORE UPPER LEVEL ENERGY TO RACE
ACROSS THE FA SUNDAY. WHILE THIS IS HAPPENING THE FRONT WILL LIFT
ACROSS THE FA AS A WARM FRONT. THIS MEANS ANOTHER CHANCE OF
SCATTERED CONVECTION ON SUNDAY.
ABOVE NORMAL TEMPERATURES ARE EXPECTED OVER THE WEEKEND. HIGHS ON
SATURDAY ARE FORECAST TO BE IN THE MID 70S...WITH UPPER 70S TO
LOWER 80S ON SUNDAY.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
RIDGE OF HIGH PRESSURE IN THE WAKE OF A WARM FRONT FROM SUNDAY NIGHT
WILL BUILD IN WITH INCREASING MOISTURE TO THE OHIO VALLEY THROUGH
WEDNESDAY. ON WEDNESDAY...A COLD FRONT WILL BE CROSSING THE REGION
EARLY...WITH SIGNIFICANTLY COOLER TEMPERATURES FOUND BEHIND IT ON
THIS DAY AND THURSDAY.
NATIONAL MODELLERS WERE LEANING TOWARDS THE SLOWER AND LESS
AMPLIFIED ECMWF ENSEMBLE SOLUTION BUT STILL HAD THE COLD FRONT
THROUGH WESTERN OHIO BY 12Z WED. THE HIGH TEMPS WED DID NOT AGREE
WITH THEIR SFC PROGS AND I COULD NOT COME IN LINE WITH THE 80 DEG AT
CMH NOTED FROM ECMWF. TOOK YESTERDAYS FORECAST AND BLENDED WITH THE
GFS/ECMWF...LEANING HEAVILY ON PREVIOUS COLDER FORECAST. THURSDAY
SHOULD BE THE COLDEST DAY IN THE FORECAST WITH HIGHS IN THE LOW TO
MID 60S. EVEN WITH A CONTINUED COLD ADVECTION PATTERN ON
FRIDAY...READINGS SHOULD BE AT LEAST A FEW DEGREES WARMER. OVERNIGHT
LOWS IN THE 60S MONDAY WILL DROP TO THE 50S TUESDAY AND ROUND OUT
THE WEEK IN 40S.
THE HIGHEST CHANCE FOR SHOWERS WILL OCCUR WITH THE FROPA TUES AND
EARLY WED. I DID NOT INCLUDE THUNDER MONDAY NIGHT THINKING THAT THE
WARM SECTOR SHOWERS WOULD BE VERY SPOTTY AND OCCUR UNDERNEATH THE
UPPER RIDGE. ONCE THE THUNDER THREAT PASSED ON WEDNESDAY IN THE WAKE
OF THE FRONT...SHOWERS WOULD BE POSSIBLE IN THE COLD POOL THURSDAY
AND TO A LESSER EXTENT FRIDAY...BOTH DUE TO THE DAYTIME SUN HITTING
A COOL AND MOIST COLUMN.
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
OBSERVATIONS INDICATE THAT AN MVFR DECK HAS DEVELOPED WEST OF THE
AREA. THIS MAY WORK EAST AND TEMPORARILY IMPACT ALL BUT THE
COLUMBUS TERMINALS EARLY IN THE TAF PERIOD. SOUTH WINDS WILL GUST
UP TO 25 KT INTO THE EVENING. THERE WILL BE A CHANCE OF
THUNDERSTORMS AFTER 0Z. HAVE A ATTEMPTED TO KEEP A NARROW WINDOW
OF VCTS WHEN PROBABILITY IS HIGHEST. APPEARS THAT PERIODIC SHOWERS
COULD OCCUR WELL INTO THE NIGHT AFFECTING PRIMARILY KCVG/KLUK UP
TO KILN. BUT UNCERTAINTY IN COVERAGE/TIMING PRECLUDES ANYTHING
MORE THAN VCSH AT THIS TIME. MODERATE CONFIDENCE THAT CEILINGS
WILL LOWER TO MVFR AREA WIDE TOWARDS 12Z. BUT DO NOT EXPECT THIS
TO LAST LONG WITH IMPROVEMENT BACK TO VFR LATE IN THE TAF PERIOD.
OUTLOOK...THUNDERSTORMS POSSIBLE SUNDAY AND AGAIN ON TUESDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...CONIGLIO/SITES
NEAR TERM...SITES
SHORT TERM...SITES
LONG TERM...FRANKS
AVIATION...
AREA FORECAST DISCUSSION
NWS TULSA OK
1246 PM CDT FRI MAY 9 2014
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
A COLD FRONT LOCATED OVER EAST CENTRAL OKLAHOMA TO FAR NORTHWEST
ARKANSAS EARLY THIS AFTERNOON IS EXPECTED TO STALL OVER SOUTHEAST
OKLAHOMA AND NORTHWEST ARKANSAS MID/LATE AFTERNOON. THIS SHOULD
KEEP MVFR CLOUD CEILINGS AHEAD/EAST OF THE FRONT AND MOSTLY CLEAR
TO PARTLY CLOUDY VFR LEVEL CLOUDS BEHIND/WEST OF THE FRONT THROUGH
THE EVENING HOURS. ALSO ALONG AND EAST OF THE FRONT...A CHANCE OF
THUNDERSTORMS WILL BE POSSIBLE THROUGH THE EVENING...THOUGH WITH
LIMITED COVERAGE WILL KEEP MENTION OUT OF THE NORTHWEST ARKANSAS
TAF SITES. THE FRONT SHOULD BEGIN TO LIFT NORTHWARD
OVERNIGHT...SHIFTING WINDS BACK OUT OF THE SOUTH TO SOUTHEAST
WITH VFR CEILINGS. DURING THE MORNING HOURS SATURDAY...AREAS OF
FOG AND IFR/MVFR CEILINGS COULD BE POSSIBLE...WITH GREATER CHANCES
ACROSS NORTHWEST ARKANSAS.
&&
.PREV DISCUSSION... /ISSUED 1026 AM CDT FRI MAY 9 2014/
..UPDATE...
DISCUSSION...
A COLD FRONT WAS POSITIONED NEAR A LINE FROM GROVE TO JUST SOUTH
OF TULSA TO NEAR OKEMAH LATE THIS MORNING. BEHIND THE
FRONT...NORTHERLY WINDS AND PARTLY CLOUDY SKIES WERE BEING
OBSERVED. AHEAD OF THE FRONT...LOW CEILINGS WERE COMMON ACROSS THE
MAJORITY OF EASTERN OKLAHOMA AND NORTHWEST ARKANSAS. ALSO SOME
PATCHY AREAS OF LIGHT DRIZZLE HAVE BEEN REPORTED WITHIN THE LOW
CLOUDS THIS MORNING. A CHANCE OF A SHOWER AND OR A THUNDERSTORM
WILL ALSO BE POSSIBLE...MAINLY ACROSS FAR NORTHWEST ARKANSAS
THROUGH THE MORNING HOURS AHEAD OF THE FRONT.
THE COLD FRONT WILL CONTINUE ITS EASTWARD MOVEMENT INTO THE
AFTERNOON HOURS AND IS EXPECTED TO STALL ACROSS SOUTHEAST OKLAHOMA
INTO NORTHWEST ARKANSAS FOR THE LATE AFTERNOON/EVENING HOURS.
SKIES SHOULD CONTINUE TO SCATTER OUT BEHIND THE FRONT AND BECOME
PARTLY CLOUDY AHEAD OF THE FRONT...ALLOWING TEMPS TO GET INTO THE
70S TO LOW 80 FROM NORTH TO SOUTH. DIURNAL HEATING AND INSTABILITY
AHEAD OF THE FRONT WILL ALLOW FOR AT LEAST A SLIGHT CHANCE OF
THUNDERSTORMS THROUGH THE EVENING HOURS. THOUGH...LATEST HRRR AND
LOCAL IN-HOUSE MODEL RUNS ARE DEVELOPING ACTIVITY JUST TO THE EAST
OF THE CWA THIS AFTERNOON. ANY THUNDERSTORMS THAT DEVELOP WILL
HAVE THE POTENTIAL TO BECOME STRONG TO SEVERE...WITH LARGE
HAIL/STRONG WINDS BEING THE MAIN HAZARDS. FOR MORNING
UPDATE...WILL CONTINUE THE SLIGHT CHANCE OF THUNDERSTORMS ACROSS
THE EAST THIS AFTERNOON AND WILL ADD PATCHY DRIZZLE THROUGH THE
LATE MORNING HOURS AHEAD OF THE FRONT. HAVE ALSO TWEAKED SKY GRIDS
AND WILL MONITOR TEMPS THROUGH THE AFTERNOON FOR ANY ADDITIONAL
UPDATES.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 62 90 72 86 / 10 20 30 10
FSM 64 87 68 86 / 20 10 20 10
MLC 65 86 71 84 / 0 10 10 10
BVO 58 90 70 87 / 10 20 30 10
FYV 58 83 67 83 / 10 20 20 10
BYV 59 84 67 84 / 10 20 20 10
MKO 62 88 69 86 / 0 10 20 10
MIO 58 88 70 87 / 10 20 30 10
F10 63 89 70 85 / 0 10 20 10
HHW 65 87 69 85 / 20 10 10 10
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
AVIATION...20
AREA FORECAST DISCUSSION
NWS TULSA OK
1026 AM CDT FRI MAY 9 2014
...UPDATE...
.DISCUSSION...
A COLD FRONT WAS POSITIONED NEAR A LINE FROM GROVE TO JUST SOUTH
OF TULSA TO NEAR OKEMAH LATE THIS MORNING. BEHIND THE
FRONT...NORTHERLY WINDS AND PARTLY CLOUDY SKIES WERE BEING
OBSERVED. AHEAD OF THE FRONT...LOW CEILINGS WERE COMMON ACROSS THE
MAJORITY OF EASTERN OKLAHOMA AND NORTHWEST ARKANSAS. ALSO SOME
PATCHY AREAS OF LIGHT DRIZZLE HAVE BEEN REPORTED WITHIN THE LOW
CLOUDS THIS MORNING. A CHANCE OF A SHOWER AND OR A THUNDERSTORM
WILL ALSO BE POSSIBLE...MAINLY ACROSS FAR NORTHWEST ARKANSAS
THROUGH THE MORNING HOURS AHEAD OF THE FRONT.
THE COLD FRONT WILL CONTINUE ITS EASTWARD MOVEMENT INTO THE
AFTERNOON HOURS AND IS EXPECTED TO STALL ACROSS SOUTHEAST OKLAHOMA
INTO NORTHWEST ARKANSAS FOR THE LATE AFTERNOON/EVENING HOURS.
SKIES SHOULD CONTINUE TO SCATTER OUT BEHIND THE FRONT AND BECOME
PARTLY CLOUDY AHEAD OF THE FRONT...ALLOWING TEMPS TO GET INTO THE
70S TO LOW 80 FROM NORTH TO SOUTH. DIURNAL HEATING AND INSTABILITY
AHEAD OF THE FRONT WILL ALLOW FOR AT LEAST A SLIGHT CHANCE OF
THUNDERSTORMS THROUGH THE EVENING HOURS. THOUGH...LATEST HRRR AND
LOCAL IN-HOUSE MODEL RUNS ARE DEVELOPING ACTIVITY JUST TO THE EAST
OF THE CWA THIS AFTERNOON. ANY THUNDERSTORMS THAT DEVELOP WILL
HAVE THE POTENTIAL TO BECOME STRONG TO SEVERE...WITH LARGE
HAIL/STRONG WINDS BEING THE MAIN HAZARDS. FOR MORNING
UPDATE...WILL CONTINUE THE SLIGHT CHANCE OF THUNDERSTORMS ACROSS
THE EAST THIS AFTERNOON AND WILL ADD PATCHY DRIZZLE THROUGH THE
LATE MORNING HOURS AHEAD OF THE FRONT. HAVE ALSO TWEAKED SKY GRIDS
AND WILL MONITOR TEMPS THROUGH THE AFTERNOON FOR ANY ADDITIONAL
UPDATES.
&&
.PRELIMINARY POINT TEMPS/POPS...
TUL 77 62 90 72 / 10 10 20 20
FSM 81 63 87 69 / 20 10 30 20
MLC 81 64 86 71 / 10 10 20 10
BVO 76 58 90 68 / 10 10 30 20
FYV 76 58 83 67 / 20 10 30 20
BYV 76 58 83 67 / 30 10 30 30
MKO 78 61 88 70 / 10 10 20 20
MIO 75 58 87 69 / 30 10 30 30
F10 78 63 88 70 / 10 10 20 20
HHW 84 65 86 70 / 10 20 20 10
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
SHORT TERM...20
AREA FORECAST DISCUSSION
NWS TULSA OK
1156 PM CDT THU MAY 8 2014
.AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
MVFR CEILINGS WILL BE PREVALENT OVERNIGHT INTO FRIDAY
MORNING...WITH SOME IFR CEILINGS POSSIBLE AT TIMES...ESPECIALLY AT
KMLC. SCATTERED SHOWERS AND THUNDERSTORMS IN NORTHEAST OKLAHOMA
WILL BE MOST LIKELY TO AFFECT KBVO FOR THE FIRST FEW HOURS OF THE
FORECAST PERIOD. CONDITIONS WILL BECOME VFR AT ALL SITES BY FRIDAY
AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 858 PM CDT THU MAY 8 2014/
DISCUSSION...
DRYLINE/FRONTAL STORMS BEGINNING TO PUSH EASTWARD INTO WESTERN
OSAGE COUNTY AT THIS TIME. BOTH THE HRRR AND THE LOCAL WRF
INDICATE ADDITIONAL DEVELOPMENT POTENTIAL PRIMARILY ALONG THE
KANSAS BORDER OVERNIGHT. SOME SEVERE THREAT WILL EXIST...BUT
LIMITED INSTABILITY FARTHER EAST WILL START TO LIMIT THE OVERALL
THREAT SOMEWHAT AS THE NIGHT GOES ON. TRENDS ON THE AFOREMENTIONED
STORMS ALREADY SHOWING THIS TO SOME EXTENT. OVER SOUTHEAST
OKLAHOMA AND WESTERN ARKANSAS...ONGOING PRECIP WILL CONTINUE TO
SHIFT EAST OF THE AREA...WITH PRECIP CHANCES DECREASING ESPECIALLY
AFTER MIDNIGHT. THIS WILL ALSO DIMINISH ANY FLOOD THREAT THAT
EXISTS. ADDITIONAL TWEAKS TO POP GRIDS WILL LIKELY BE
FORTHCOMING...ESPECIALLY FOR POST 06Z TIME FRAME. TEMPERATURE
WISE...WITH CLOUDS REMAINING THROUGH MOST OF THE
NIGHT...LOWS WILL REMAIN RELATIVELY WARM...IN THE 60S FOR MOST OF
THE AREA.
PREV DISCUSSION... /ISSUED 638 PM CDT THU MAY 8 2014/
AVIATION...
CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM.
CEILINGS WILL BECOME MVFR AT ALL LOCATIONS OVERNIGHT. AN ISOLATED
SHOWER OR THUNDERSTORM WILL BE POSSIBLE...ESPECIALLY AT THE
NORTHEAST OKLAHOMA AND NORTHWEST ARKANSAS SITES...BUT THE CHANCES
ARE TOO LOW TO INCLUDE IN THE TAFS. CONDITIONS WILL IMPROVE TO VFR
BY FRIDAY AFTERNOON AND WINDS WILL BECOME LIGHT AS A WEAK FRONTAL
BOUNDARY ACROSS THE AREA BEGINS TO WASH OUT.
PREV DISCUSSION... /ISSUED 302 PM CDT THU MAY 8 2014/
DISCUSSION...
A LARGE AREA OF RAINFALL WITH EMBEDDED THUNDERSTORMS CONTINUES TO
MOVE EASTWARD ACROSS THE CWA THIS AFTERNOON AHEAD OF AN UPPER TROUGH
TRAVERSING THE SOUTHERN PLAINS. THE PRECIPITATION IS ENDING FROM
WEST TO EAST ACROSS MUCH OF NORTHEAST OKLAHOMA WITH SOME CLEARING
BEHIND THAT. THE DRYLINE REMAINS TO OUR WEST AND A COLD FRONT REMAINS TO
OUR NORTH. THIS SCENARIO SHOULD BE CONDUCIVE FOR STORMS TO REDEVELOP
LATE THIS AFTERNOON AND EVENING IN NORTHEAST OKLAHOMA AND POSSIBLY
INTO NORTHWEST ARKANSAS.
AFTER TONIGHT... THUNDERSTORM CHANCES WILL EASE BACK FOR A COUPLE OF
DAYS AS UPPER FLOW BRIEFLY BECOMES ZONAL. ANOTHER UPPER TROUGH
DEVELOPING TO OUR WEST WILL MOVE ACROSS THE AREA SUNDAY INTO MONDAY.
A COLD FRONT ACCOMPANYING THIS SYSTEM WILL SWEEP ACROSS THE CWA
BEGINNING EARLY MONDAY MORNING. THUNDERSTORM CHANCES WILL INCREASE
ALONG AND AHEAD OF THE FRONT. SEVERE STORMS MAY BE POSSIBLE EVEN
THOUGH THE TIMING OF FRONTAL PASSAGE IS DISADVANTAGEOUS.
FOR THE REMAINDER OF NEXT WEEK... MILD CONDITIONS WILL PREVAIL.
PRECIPITATION CHANCES WILL BE MINIMAL WITH TEMPERATURES SLIGHTLY
BELOW SEASONAL AVERAGES.
&&
.TSA WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
AR...NONE.
&&
$$
AVIATION...05
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
540 PM EDT FRI MAY 9 2014
.SYNOPSIS...
A SURFACE WARM FRONT EXTENDING FROM THE FINGER LAKES REGION OF
NEW YORK SOUTH THROUGH THE SUSQUEHANNA VALLEY WILL DRIFT TO THE
NORTHEAST OF THE REGION TONIGHT. BEHIND THE FRONT IN THE WARM
SECTOR...ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL
OCCUR OVER THE WESTERN HALF OF THE STATE LATE THIS AFTERNOON.
MORE NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS WILL DRIFT EAST
ACROSS PENNSYLVANIA TONIGHT AND SATURDAY...AS A COLD FRONT SLIDES
EAST FROM THE OHIO VALLEY. WARM...AND GENERALLY DRY WEATHER WILL
OCCUR ON SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
SCT SHRA AND A FEW TSRA DEVELOPING ACROSS THE WESTERN HALF OF PA
EARLY THIS EVENING AHEAD OF SHORTWAVE LIFTING OUT OF THE OHIO
VALLEY. DESPITE FAIRLY IMPRESSIVE SHEAR...THE CAPE AND ASSOC SVR
THREAT SHOULD REMAIN LOW. MORE NUMEROUS SHOWERS/TSTMS EXPECTED TO
WORK EASTWARD INTO PA LATER THIS EVENING...AS FORCING INCREASES
AHEAD OF SHORTWAVE. LATEST NAM/RAP OUTPUT SUGGEST THE BEST CHC OF
RAIN WILL WORK WEST TO EAST ACROSS CENTRAL PA BTWN 02Z-08Z.
BLEND OF LATEST ENSEMBLE AND OPER MDLS SUPPORT AVERAGE QPF THRU
12Z RANGING FROM ALMOST A HALF INCH ACROSS THE NW MTNS TO A TENTH
OF AN INCH OVR THE LOWER SUSQ VALLEY. OF COURSE...GIVEN POSITIVE
PWAT ANOMALIES IN THE 2-3SD RANGE...EXPECT LOCALLY HIGHER AMTS.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/...
COLD FRONT PUSHES ACROSS THE STATE ON SAT...WITH NUMEROUS SHOWERS
AND ISO TSTMS CONTINUING THROUGH MAINLY FIRST HALF OF THE DAY
AHEAD OF IT. TOTAL QPF AMOUNTS TONIGHT INTO SAT WILL BE 0.25-0.50.
LATE DAY SAT INTO SUN THE RIDGE BUILDS BACK INTO PA...WITH MILD
WEATHER CONTINUING.
&&
.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
SHRA/TSRA AND HIGHER PWATS SHUNTED EAST OF THE REGION SAT NIGHT
AS THE COLD FRONT PASSES. SUNDAY LOOKS LIKE A PRETTY NICE
DAY...WITH SKIES BECOMING PARTLY TO MOSTLY SUNNY.
UPPER-LEVEL RIDGE ESTABLISHES ITSELF EARLY NEXT WEEK...PROVIDING
INCREASING WARMTH AND HUMIDITY ACROSS CENTRAL PA. AN AFTN
SHRA/TSRA IS POSSIBLE MONDAY...WITH A BETTER CHC TUESDAY AS THE
NEXT FRONTAL SYSTEM NEARS.
WED AND THU LOOK UNSETTLED...WITH A GOOD CHC OF SHRA/TSRA AS A
SLOW-MOVING FRONT CROSSES THE REGION. THE 12Z ECMWF DEVELOPS A
WAVE OF LOW PRES ON THE FRONT...SLOWING THE FRONTAL PASSAGE UNTIL
SOMETIME FRIDAY. THEREFORE...HELD ONTO SOME POPS INTO FRIDAY DUE
TO THE UNCERTAINTY.
&&
.AVIATION /22Z FRIDAY THROUGH WEDNESDAY/...
TAFS ADJUSTED FOR CONVECTION. STORMS TO THE SW OF UNV MOVING
NE...WHILE STORMS NEAR BFD MOVING MORE TO THE EAST...AND THIS
SET HAVE A HISTORY OF GUSTY WINDS.
EARLIER DISCUSSION BELOW.
CIG RESTRICTIONS HAVE FINALLY ABATED ACROSS THE LOWER SUSQ AS
FORMERLY STABLE LOW LEVELS BEGIN TO MIX JUST AHEAD OF A SLOWLY
APPROACHING WARM FRONT...BUT MVFR VSBYS IN HAZE WILL REMAIN
THROUGH THE AFTERNOON.
ON THE OTHER SIDE OF THE FRONT IN THE WARM SECTOR...VFR CONDS
WILL PREVAIL OVER THE WRN/CNTRL AIRSPACE INTO LATE EVENING/EARLY
SAT MORNING. HRRR MODEL DATA INDICATE ISOLD-SCT SHWRS/TSTMS
DEVELOPING OVER THE WRN 1/3 OF THE AIRSPACE BY MID AFTERNOON...AND
RADAR BEGINNING TO CONFIRM THAT THINKING...WITH A MORE PERSISTENT
LINE OF CONVECTION MOVING ACROSS E OHIO. ADDED VCTS TO KBFD TAF
AFTER 21Z...BUT CONFIDENCE IN TERMINAL IMPACTS INCLUDING TIMING
IS LOW ELSEWHERE AND CONTINUED THE VCSH TO CONVEY POTENTIAL UNTIL
STORMS BECOME MORE IMMINENT AT SPECIFIC TERMINALS LATE THIS AFT
AND EARLY THIS EVE.
HIGHER PROBS FOR PRE-FRONTAL SHWRS/ISO TSTMS TONIGHT WITH
MARGINAL RESTRICTIONS AGAIN DEVELOPING...ESP WRN 1/3. WIDESPREAD
RAIN SHOWERS/ISO TSTMS REMAIN POSS THROUGH FIRST HALF OF SAT
BEFORE TAPERING OFF FROM THE NW.
.OUTLOOK...
SAT...SCT-NMRS SHRA/TSTMS THUNDERSTORMS WITH OCNL MVFR CIGS AND
VSBYS ALONG/AHEAD OF A SLOW MOVING COLD FRONT.
SUN...BCMG VFR.
SUN NGT-TUE...VFR/MVFR WITH CHC SHRA/TSRA.
WED...RAIN AND RESTRICTIONS LIKELY.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT/RXR
NEAR TERM...FITZGERALD/RXR
SHORT TERM...RXR
LONG TERM...EVANEGO
AVIATION...MARTIN/RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
521 PM EDT FRI MAY 9 2014
.SYNOPSIS...
A SURFACE WARM FRONT EXTENDING FROM THE FINGER LAKES REGION OF NEW
YORK SOUTH THROUGH THE SUSQUEHANNA VALLEY WILL DRIFT TO THE
NORTHEAST OF THE REGION TONIGHT. BEHIND THE FRONT IN THE WARM
SECTOR...ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL
OCCUR OVER THE WESTERN HALF OF THE STATE LATE THIS AFTERNOON.
MORE NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS WILL DRIFT EAST
ACROSS PENNSYLVANIA TONIGHT AND SATURDAY...AS A COLD FRONT SLIDES
EAST FROM THE OHIO VALLEY. WARM...AND GENERALLY DRY WEATHER WILL
OCCUR ON SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
SCT SHRA AND A FEW TSRA DEVELOPING ACROSS THE WESTERN HALF OF PA
EARLY THIS EVENING AHEAD OF SHORTWAVE LIFTING OUT OF THE OHIO
VALLEY. DESPITE FAIRLY IMPRESSIVE SHEAR...THE CAPE AND ASSOC SVR
THREAT SHOULD REMAIN LOW. MORE NUMEROUS SHOWERS/TSTMS EXPECTED TO
WORK EASTWARD INTO PA LATER THIS EVENING...AS FORCING INCREASES
AHEAD OF SHORTWAVE. LATEST NAM/RAP OUTPUT SUGGEST THE BEST CHC OF
RAIN WILL WORK WEST TO EAST ACROSS CENTRAL PA BTWN 02Z-08Z.
BLEND OF LATEST ENSEMBLE AND OPER MDLS SUPPORT AVERAGE QPF THRU
12Z RANGING FROM ALMOST A HALF INCH ACROSS THE NW MTNS TO A TENTH
OF AN INCH OVR THE LOWER SUSQ VALLEY. OF COURSE...GIVEN POSITIVE
PWAT ANOMALIES IN THE 2-3SD RANGE...EXPECT LOCALLY HIGHER AMTS.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/...
COLD FRONT PUSHES ACROSS THE STATE ON SAT...WITH NUMEROUS SHOWERS
AND ISO TSTMS CONTINUING THROUGH MAINLY FIRST HALF OF THE DAY
AHEAD OF IT. TOTAL QPF AMOUNTS TONIGHT INTO SAT WILL BE 0.25-0.50.
LATE DAY SAT INTO SUN THE RIDGE BUILDS BACK INTO PA...WITH MILD
WEATHER CONTINUING.
&&
.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
SHRA/TSRA AND HIGHER PWATS SHUNTED EAST OF THE REGION SAT NIGHT
AS THE COLD FRONT PASSES. SUNDAY LOOKS LIKE A PRETTY NICE
DAY...WITH SKIES BECOMING PARTLY TO MOSTLY SUNNY.
UPPER-LEVEL RIDGE ESTABLISHES ITSELF EARLY NEXT WEEK...PROVIDING
INCREASING WARMTH AND HUMIDITY ACROSS CENTRAL PA. AN AFTN
SHRA/TSRA IS POSSIBLE MONDAY...WITH A BETTER CHC TUESDAY AS THE
NEXT FRONTAL SYSTEM NEARS.
WED AND THU LOOK UNSETTLED...WITH A GOOD CHC OF SHRA/TSRA AS A
SLOW-MOVING FRONT CROSSES THE REGION. THE 12Z ECMWF DEVELOPS A
WAVE OF LOW PRES ON THE FRONT...SLOWING THE FRONTAL PASSAGE UNTIL
SOMETIME FRIDAY. THEREFORE...HELD ONTO SOME POPS INTO FRIDAY DUE
TO THE UNCERTAINTY.
&&
.AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
CIG RESTRICTIONS HAVE FINALLY ABATED ACROSS THE LOWER SUSQ AS
FORMERLY STABLE LOW LEVELS BEGIN TO MIX JUST AHEAD OF A SLOWLY
APPROACHING WARM FRONT...BUT MVFR VSBYS IN HAZE WILL REMAIN
THROUGH THE AFTERNOON.
ON THE OTHER SIDE OF THE FRONT IN THE WARM SECTOR...VFR CONDS
WILL PREVAIL OVER THE WRN/CNTRL AIRSPACE INTO LATE EVENING/EARLY
SAT MORNING. HRRR MODEL DATA INDICATE ISOLD-SCT SHWRS/TSTMS
DEVELOPING OVER THE WRN 1/3 OF THE AIRSPACE BY MID AFTERNOON...AND
RADAR BEGINNING TO CONFIRM THAT THINKING...WITH A MORE PERSISTENT
LINE OF CONVECTION MOVING ACROSS E OHIO. ADDED VCTS TO KBFD TAF
AFTER 21Z...BUT CONFIDENCE IN TERMINAL IMPACTS INCLUDING TIMING
IS LOW ELSEWHERE AND CONTINUED THE VCSH TO CONVEY POTENTIAL UNTIL
STORMS BECOME MORE IMMINENT AT SPECIFIC TERMINALS LATE THIS AFT
AND EARLY THIS EVE.
HIGHER PROBS FOR PRE-FRONTAL SHWRS/ISO TSTMS TONIGHT WITH
MARGINAL RESTRICTIONS AGAIN DEVELOPING...ESP WRN 1/3. WIDESPREAD
RAIN SHOWERS/ISO TSTMS REMAIN POSS THROUGH FIRST HALF OF SAT
BEFORE TAPERING OFF FROM THE NW.
.OUTLOOK...
SAT...SCT-NMRS SHRA/TSTMS THUNDERSTORMS WITH OCNL MVFR CIGS AND
VSBYS ALONG/AHEAD OF A SLOW MOVING COLD FRONT.
SUN...BCMG VFR.
SUN NGT-TUE...VFR/MVFR WITH CHC SHRA/TSRA.
WED...RAIN AND RESTRICTIONS LIKELY.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT/RXR
NEAR TERM...FITZGERALD/RXR
SHORT TERM...RXR
LONG TERM...EVANEGO
AVIATION...RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
339 PM EDT FRI MAY 9 2014
.SYNOPSIS...
A SURFACE WARM FRONT EXTENDING FROM THE FINGER LAKES REGION OF NEW
YORK SOUTH THROUGH THE SUSQUEHANNA VALLEY WILL DRIFT TO THE
NORTHEAST OF THE REGION TONIGHT. BEHIND THE FRONT IN THE WARM
SECTOR...ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL
OCCUR OVER THE WESTERN HALF OF THE STATE LATE THIS AFTERNOON.
MORE NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS WILL DRIFT EAST
ACROSS PENNSYLVANIA TONIGHT AND SATURDAY...AS A COLD FRONT SLIDES
EAST FROM THE OHIO VALLEY. WARM...AND GENERALLY DRY WEATHER WILL
OCCUR ON SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
LOW CLOUDS ACROSS LOWER SUSQ FINALLY HAVE BROKEN THIS MID
AFTERNOON JUST AHEAD OF A SLOWLY APPROACHING WARM FRONT.
BEHIND THE FRONT IN THE WARM SECTOR...ISO SHOWERS/TSTMS DEVELOPING
ACROSS W PA AS FORCING/LIFT BEGIN TO INCREASE AHEAD OF SLOWLY
APPROACHING COLD FRONT. MORE NUMEROUS SHOWERS/TSTMS OVER
OHIO...AND THESE WILL WORK EASTWARD INTO PA BY EARLY EVENING. IN
ADDITION...PRECIP SHIELD WILL FILL IN OVERNIGHT AS INCREASING
SOUTHWESTERLY LLJ SHIFTS EASTWARD.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/...
COLD FRONT PUSHES ACROSS THE STATE ON SAT...WITH NUMEROUS SHOWERS
AND ISO TSTMS CONTINUING THROUGH MAINLY FIRST HALF OF THE DAY
AHEAD OF IT. TOTAL QPF AMOUNTS TONIGHT INTO SAT WILL BE 0.25-0.50.
LATE DAY SAT INTO SUN THE RIDGE BUILDS BACK INTO PA...WITH MILD
WEATHER CONTINUING.
&&
.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
SHRA/TSRA AND HIGHER PWATS SHUNTED EAST OF THE REGION SAT NIGHT
AS THE COLD FRONT PASSES. SUNDAY LOOKS LIKE A PRETTY NICE
DAY...WITH SKIES BECOMING PARTLY TO MOSTLY SUNNY.
UPPER-LEVEL RIDGE ESTABLISHES ITSELF EARLY NEXT WEEK...PROVIDING
INCREASING WARMTH AND HUMIDITY ACROSS CENTRAL PA. AN AFTN
SHRA/TSRA IS POSSIBLE MONDAY...WITH A BETTER CHC TUESDAY AS THE
NEXT FRONTAL SYSTEM NEARS.
WED AND THU LOOK UNSETTLED...WITH A GOOD CHC OF SHRA/TSRA AS A
SLOW-MOVING FRONT CROSSES THE REGION. THE 12Z ECMWF DEVELOPS A
WAVE OF LOW PRES ON THE FRONT...SLOWING THE FRONTAL PASSAGE UNTIL
SOMETIME FRIDAY. THEREFORE...HELD ONTO SOME POPS INTO FRIDAY DUE
TO THE UNCERTAINTY.
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
CIG RESTRICTIONS HAVE FINALLY ABATED ACROSS THE LOWER SUSQ AS
FORMERLY STABLE LOW LEVELS BEGIN TO MIX JUST AHEAD OF A SLOWLY
APPROACHING WARM FRONT...BUT MVFR VSBYS IN HAZE WILL REMAIN
THROUGH THE AFTERNOON.
ON THE OTHER SIDE OF THE FRONT IN THE WARM SECTOR...VFR CONDS
WILL PREVAIL OVER THE WRN/CNTRL AIRSPACE INTO LATE EVENING/EARLY
SAT MORNING. HRRR MODEL DATA INDICATE ISOLD-SCT SHWRS/TSTMS
DEVELOPING OVER THE WRN 1/3 OF THE AIRSPACE BY MID AFTERNOON...AND
RADAR BEGINNING TO CONFIRM THAT THINKING...WITH A MORE PERSISTENT
LINE OF CONVECTION MOVING ACROSS E OHIO. ADDED VCTS TO KBFD TAF
AFTER 21Z...BUT CONFIDENCE IN TERMINAL IMPACTS INCLUDING TIMING
IS LOW ELSEWHERE AND CONTINUED THE VCSH TO CONVEY POTENTIAL UNTIL
STORMS BECOME MORE IMMINENT AT SPECIFIC TERMINALS LATE THIS AFT
AND EARLY THIS EVE.
HIGHER PROBS FOR PRE-FRONTAL SHWRS/ISO TSTMS TONIGHT WITH
MARGINAL RESTRICTIONS AGAIN DEVELOPING...ESP WRN 1/3. WIDESPREAD
RAIN SHOWERS/ISO TSTMS REMAIN POSS THROUGH FIRST HALF OF SAT
BEFORE TAPERING OFF FROM THE NW.
.OUTLOOK...
SAT...SCT-NMRS SHRA/TSTMS THUNDERSTORMS WITH OCNL MVFR CIGS AND
VSBYS ALONG/AHEAD OF A SLOW MOVING COLD FRONT.
SUN...BCMG VFR.
SUN NGT-TUE...VFR/MVFR WITH CHC SHRA/TSRA.
WED...RAIN AND RESTRICTIONS LIKELY.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT/RXR
NEAR TERM...RXR
SHORT TERM...RXR
LONG TERM...EVANEGO
AVIATION...RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
330 PM EDT FRI MAY 9 2014
.SYNOPSIS...
A SURFACE WARM FRONT EXTENDING FROM THE FINGER LAKES REGION OF NEW
YORK SOUTH THROUGH THE SUSQUEHANNA VALLEY WILL DRIFT TO THE
NORTHEAST OF THE REGION TONIGHT. BEHIND THE FRONT IN THE WARM
SECTOR...ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL
OCCUR OVER THE WESTERN HALF OF THE STATE LATE THIS AFTERNOON.
MORE NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS WILL DRIFT EAST
ACROSS PENNSYLVANIA TONIGHT AND SATURDAY...AS A COLD FRONT SLIDES
EAST FROM THE OHIO VALLEY. WARM...AND GENERALLY DRY WEATHER WILL
OCCUR ON SUNDAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
LOW CLOUDS ACROSS LOWER SUSQ FINALLY HAVE BROKEN THIS MID
AFTERNOON JUST AHEAD OF A SLOWLY APPROACHING WARM FRONT.
BEHIND THE FRONT IN THE WARM SECTOR...ISO SHOWERS/TSTMS DEVELOPING
ACROSS W PA AS FORCING/LIFT BEGIN TO INCREASE AHEAD OF SLOWLY
APPROACHING COLD FRONT. MORE NUMEROUS SHOWERS/TSTMS OVER
OHIO...AND THESE WILL WORK EASTWARD INTO PA BY EARLY EVENING. IN
ADDITION...PRECIP SHIELD WILL FILL IN OVERNIGHT AS INCREASING
SOUTHWESTERLY LLJ SHIFTS EASTWARD.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH 6 PM SATURDAY/...
COLD FRONT PUSHES ACROSS THE STATE ON SAT...WITH NUMEROUS SHOWERS
AND ISO TSTMS CONTINUING THROUGH MAINLY FIRST HALF OF THE DAY
AHEAD OF IT. TOTAL QPF AMOUNTS TONIGHT INTO SAT WILL BE 0.25-0.50.
LATE DAY SAT INTO SUN THE RIDGE BUILDS BACK INTO PA...WITH MILD
WEATHER CONTINUING.
&&
.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
SFC COLD FRONT WILL PUSH SOUTH OF THE STATE BY LATE SAT
NIGHT...WITH A DRY SUNDAY LIKELY FOR MOST OF CENTRAL PA IN IT/S
WAKE. GIVEN THE NW FLOW...ALONG WITH RESIDUAL MOISTURE...THERE IS
A SLIGHT CHANCE FOR UPSLOPE SHOWERS IN THE NW MTNS. TEMPERATURES
WILL DROP IN THE WAKE OF THE COLD FRONT ON SATURDAY...WITH HIGHS
CLOSER TO NORMAL.
HOWEVER TEMPERATURES WILL REBOUND TO THE MID 70S BY SUNDAY...AND
INTO THE 80S AS A BNDRY SHOULD COME CHARGING BACK AS A WARM FRONT
ON MONDAY. DEEP SOUTHERLY FLOW DEVELOPS AHEAD OF DIGGING TROF OVR
THE PLAINS. SCT CONVECTION IS LIKELY TO ACCOMPANY PASSAGE OF
WFRONT MONDAY. PASSAGE OF RIDGE AXIS AND ANOMALOUS TEMPS ALOFT
COULD SUPPRESS CONVECTION TUESDAY AND RESULT IN A VERY WARM DAY
WITH HIGHS WELL INTO THE 80S GIVEN 12Z EC ENS MEAN 8H TEMPS ARND
16C.
THE GFS ENSEMBLES SHOW SIGNIFICANT TIMING DIFFERENCES WITH REGARD
TO PASSAGE OF THE NEXT DEEP TROF AND ASSOCIATED SLOW- MOVING COLD
FRONT DURING THE MIDDLE OF NEXT WEEK. HOWEVER...EC ENSEMBLE AND
GEFS SUPPORT A SLOWER SOLUTION THAN THE OPERATIONAL GFS...IMPLYING
A GOOD CHANCE OF WET WEATHER BY WED. THIS DEEP TROUGH SHOULD
DICTATE THE PATTERN LATE NEXT WEEK.
&&
.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
CIG RESTRICTIONS HAVE FINALLY ABATED ACROSS THE LOWER SUSQ AS
FORMERLY STABLE LOW LEVELS BEGIN TO MIX JUST AHEAD OF A SLOWLY
APPROACHING WARM FRONT...BUT MVFR VSBYS IN HAZE WILL REMAIN
THROUGH THE AFTERNOON.
ON THE OTHER SIDE OF THE FRONT IN THE WARM SECTOR...VFR CONDS
WILL PREVAIL OVER THE WRN/CNTRL AIRSPACE INTO LATE EVENING/EARLY
SAT MORNING. HRRR MODEL DATA INDICATE ISOLD-SCT SHWRS/TSTMS
DEVELOPING OVER THE WRN 1/3 OF THE AIRSPACE BY MID AFTERNOON...AND
RADAR BEGINNING TO CONFIRM THAT THINKING...WITH A MORE PERSISTENT
LINE OF CONVECTION MOVING ACROSS E OHIO. ADDED VCTS TO KBFD TAF
AFTER 21Z...BUT CONFIDENCE IN TERMINAL IMPACTS INCLUDING TIMING
IS LOW ELSEWHERE AND CONTINUED THE VCSH TO CONVEY POTENTIAL UNTIL
STORMS BECOME MORE IMMINENT AT SPECIFIC TERMINALS LATE THIS AFT
AND EARLY THIS EVE.
HIGHER PROBS FOR PRE-FRONTAL SHWRS/ISO TSTMS TONIGHT WITH
MARGINAL RESTRICTIONS AGAIN DEVELOPING...ESP WRN 1/3. WIDESPREAD
RAIN SHOWERS/ISO TSTMS REMAIN POSS THROUGH FIRST HALF OF SAT
BEFORE TAPERING OFF FROM THE NW.
.OUTLOOK...
SAT...SCT-NMRS SHRA/TSTMS THUNDERSTORMS WITH OCNL MVFR CIGS AND
VSBYS ALONG/AHEAD OF A SLOW MOVING COLD FRONT.
SUN...BCMG VFR.
SUN NGT-TUE...VFR/MVFR WITH CHC SHRA/TSRA.
WED...RAIN AND RESTRICTIONS LIKELY.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...LAMBERT/RXR
NEAR TERM...RXR
SHORT TERM...RXR
LONG TERM...FITZGERALD/LAMBERT
AVIATION...RXR
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1010 PM EDT SAT MAY 10 2014
.SYNOPSIS...
BERMUDA HIGH PRESSURE WILL STRENGTHEN OVER THE SOUTHEAST SUNDAY
THROUGH TUESDAY. A STRONG LOW PRESSURE SYSTEM MOVING EAST FROM THE
PLAINS WILL BRING A COLD FRONT TO THE AREA BY THURSDAY...WITH A
SIGNIFICANT COOLDOWN EXPECTED LATE WEEK INTO THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AS OF 10 PM...CONVECTION HAS NEARLY TOTALLY DISSIPATED ACROSS THE
CWA...ONLY A FEW SHRA ACROSS THE LAKELANDS. DEWPOINT DEPRESSIONS
HAVE NARROWED TO 1 TO 3 DEGREES AT MOST SITES. AS HIGH CLOUDS
DECREASE LATER TONIGHT...THE POTENTIAL FOR FOG LOOKS VERY LIKELY. I
WILL UPDATE TO ADJUST POP...T/TD...AND FOG TIMING.
AS OF 755 PM...A FADING BAND OF SHOWERS OVER EASTERN TN IS EXPECTED
TO ASH OUT NEAR THE NC/TN LINE OVER THE NEXT TWO HOURS. BASED ON
COVERAGE OF RAINFALL THIS AFTERNOON AND EVENING...CONDITIONS APPEAR
FAVORABLE FOR AT LEAST MVFR FOG TONIGHT. I WILL UPDATE THE FORECAST
TO ADJUST POPS AND INCREASE FOG MENTION.
AS OF 550 PM...WIDESPREAD CONVECTION HAS WEAKENED AND PUSHED EAST OF
THE FORECAST AREA. CONVECTION COVERAGE WILL REMAIN THE GREATEST OVER
THE EASTERN PIEDMONT OVER THE NEXT TWO HOURS...POSSIBLY FOLLOWED BY
THE ARRIVAL OF A LINE OF SHRA/TSRA NEAR THE NC/TN LINE. I WILL
UPDATE THE FORECAST TO ADJUST TO LATEST TRENDS. TEMPERATURES AND
DEWPOINTS WILL BE POPULATED WITH THE LATEST OBSERVATIONS.
AS OF 230 PM...AS EXPECTED...CONVECTION HAS EXPLODED ACRS THE
PIEDMONT FROM NE GA INTO THE SW NC PIEDMONT...WHERE CAPE VALUES OF
1500-2000 J/KG WERE ANALYZED BY THE LAPS. STORMS ARE REACHING
MARGINAL CORE HEIGHTS (55 DBZ NEAR 22 KFT) WHICH MAY BE ENUF TO
PRODUCE 1" HAIL AND DAMAGING WIND GUSTS. OVERALL...STILL EXPECT
MAINLY SUB-SEVERE STORMS AND SHOWERS WITH BRIEF TORRENTIAL DOWNPOURS
AND GUSTY WINDS. THE CELLS SEEM TO HAVE ENUF MOVEMENT TO LIMIT HEAVY
RAIN/FLOODING THREAT. CONVECTION SHUD WANE FAIRLY QUICKLY WITH LOSS
OF HEATING...AS ATMOSPHERE WILL BE WORKED OVER AND AN UPPER
SHORTWAVE WILL EXIT TO THE EAST.
OVERNIGHT...THE NAM AND GFS FCST SNDGS SHOW PLENTY OF MID LVL AND
UPR LVL DRYING BEHIND A PASSING SHORTWAVE...WHILE THE LLVLS REMAIN
MOIST. A COLD FRONT APPEARS TO WASH OUT TO THE NORTH OF THE
CWFA...SO WINDS WILL REMAIN LIGHT OR CALM AS WELL. GUIDANCE MAY BE
UNDERDONE ON FOG POTENTIAL. CERTAINLY IF SKIES CAN CLEAR EARLY
ENUF...THERE MAY BE AREAS OF FOG...POSSIBLY DENSE. TEMPS ARE FCST TO
FALL INTO THE 50S MTNS AND LWR 60S...WHICH IS WELL BELOW THE CURRENT
DWPTS.
SUNDAY...THE 500 MB HIGH BEGINS TO REASSERT ITSELF ACRS THE
SOUTHEAST STATES...WITH A BERMUDA HIGH TO THE EAST. OUR AREA SEEMS
TO BE IN BETWEEN THE BETTER MOISTURE TO SOUTH AND STRONGER
SUBSIDENCE AND DRIER AIR TO THE NORTH. THE NAM HAS PLENTY OF BL
MOISTURE ACRS THE AREA WITH A LIGHT SE FLOW. WHILE THE GFS IS ON
AVERAGE ABOUT 5 DEG LOWER OF DWPTS AND HAS A WEAK SW/W FLOW. THIS
RESULTS IN MORE CAPE ON THE NAM...ESP ACRS THE PIEDMONT.
HOWEVER...EVEN WITH THE INCREASED CAPE...THE NAM DOES NOT LOOK TOO
EXCITED ABOUT CONVECTION. I OPTED TO ONLY MAKE MINOR TWEAKS TO THE
POPS INHERITED FROM LAST NIGHT. STILL EXPECT AT LEAST ISOLD SHWRS
AND TSTMS...PERHAPS A LITTLE BETTER COVERAGE IN THE MTNS WHERE
DIFFERENTIAL MTN HEATING SHUD PROVIDE BEST TRIGGERING. TEMPS ARE
EXPECTED TO REBOUND INTO THE UPR 70S TO LWR 80S...AND MID 80S ACRS
THE PIEDMONT.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
AS OF 300 PM EDT SATURDAY...A PROMINENT 588 DM H5 RIDGE WILL BE IN
PLACE ACROSS THE SOUTHEAST ON MONDAY...WITH A HIGH AMPLITUDE PATTERN
FIRMLY IN PLACE BETWEEN A DEEP CENTRAL CONUS TROUGH AND EAST COAST
RIDGE BY TUE. DESPITE THE RIDGING AND RESULTANT MID LEVEL
INVERSION...PERSISTENT LOW LEVEL SRLY UPSLOPE FLOW SHOULD PROVIDE
TRIGGERING ACROSS THE MTNS. WILL THUS FEATURE MAINLY SCATTERED
DIURNAL CONVECTION MON AND TUE AFTN...WITH A FOCUS IN THE MTNS.
EXPECT WARM TEMPS THROUGH THE PERIOD.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 300 PM EDT SATURDAY...UPPER DIVERGENCE AND IMPROVING SRLY FLOW
WILL AID CONVECTIVE COVERAGE STARTING WED...AND A MORE NON DIURNAL
NATURE IS EXPECTED GIVEN THE APPROACHING HIGH AMPLITUDE TROUGH AND
ASSOCIATED SURFACE FRONT. THE DEEPEST FORCING AND MOISTURE SHOULD
ARRIVE THU AS A BROAD AREA OF STRONG Q VECTOR CONVERGENCE CROSSES
THE REGION...ESPECIALLY DURING THE AFTN/EVENING HOURS. THIS COULD
LEAD TO STRONG TO SEVERE CONVECTION...BUT THE TIMING REMAINS
SOMEWHAT UNCERTAIN. IN ADDITION...MOST OF THE MODELS STILL DEPICT A
TROPICAL FEATURE MOVING NWD FROM THE FL COASTAL WATERS TO THE
CAROLINA COASTAL WATERS THU. THIS SHOULD REMAIN EAST OF THE AREA.
THE DEEP ERN TROUGH WILL PERSIST FRI THROUGH SAT...BUT WITH DRIER
AIR AND COOLER TEMPERATURES ARRIVING. ADDITIONAL ENERGY ROUNDING THE
TROUGH WILL BE HARD TO TIME...BUT THE BEST CONSENSUS FOR THE NEXT
VORT LOBE AND ASSOC MOISTURE APPEARS ON SAT...AND THERE MAY BE SOME
LOW LEVEL WAVE FORMATION ALONG A BAROCLINIC ZONE. WILL FEATURE LOW
END CHC GIVEN THE STEEP LAPSE RATES UNDER THE TROUGH.
&&
.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
AT KCLT...AT 2330Z...A HEAVY SHOWERS WAS PASSING JUST SOUTH OF THE
TERMINAL. IT APPEARS THAT ADDITIONAL LIGHT SHOWERS MAY PASS NEAR THE
TERMINAL THROUGH 1Z. I WILL INDICATE VCSH. OVERNIGHT...THE PRIMARY
CONCERN WILL BE THE POTENTIAL OF FOG...PROVIDED LIGHT TO CALM WINDS
AND WET SOIL. THE KCLT ASOS MEASURED A HALF INCH TODAY. AS A
RESULT...THE 21Z HRRR AND 18Z NAM12 INDICATE VERY LOW CONDENSATION
PRESSURE DEFICITS LATE TONIGHT INTO EARLY SUNDAY MORNING. I WILL
INDICATE IFR FOG DEVELOPING BY 6Z...DISSIPATING BY 13Z. SCT CU MAY
DEVELOP BY LATE MORNING...WITH LIGHT ENE WINDS.
ELSEWHERE...A FADING BAND OF SHOWERS OVER EASTERN TN IS EXPECTED TO
DISSIPATE NEAR THE NC/TN LINE OVER THE NEXT TWO HOURS. BASED ON
COVERAGE OF RAINFALL THIS AFTERNOON AND EVENING...CONDITIONS APPEAR
FAVORABLE FOR AT LEAST MVFR FOG TONIGHT. KAVL SHOULD REPEAT FOG
TIMING AS OBSERVED THIS MORNING...WITH LIFR BY 9Z. SCT CU MAY
DEVELOP BY LATE MORNING...WITH LIGHT ENE WINDS.
OUTLOOK...HIGH PRESSURE RETURNS ON MONDAY...BUT AFTERNOON AND
EVENING CONVECTION WILL BE POSSIBLE BOTH DAYS. WEDNESDAY AND
THURSDAY FEATURE A SLOW MOVING COLD FRONT...YIELDING A BETTER CHANCE
OF RESTRICTIONS IN PROLONGED PRECIPITATION.
CONFIDENCE TABLE...
02-08Z 08-14Z 14-20Z 20-02Z
KCLT HIGH 94% HIGH 95% HIGH 94% HIGH 100%
KGSP HIGH 100% MED 75% HIGH 100% HIGH 100%
KAVL HIGH 97% HIGH 90% HIGH 97% HIGH 100%
KHKY HIGH 88% HIGH 80% HIGH 100% HIGH 100%
KGMU HIGH 100% HIGH 89% HIGH 100% HIGH 100%
KAND HIGH 95% MED 70% HIGH 100% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...HG
NEAR TERM...ARK/NED
SHORT TERM...HG
LONG TERM...HG
AVIATION...NED
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
757 PM EDT SAT MAY 10 2014
.SYNOPSIS...
BERMUDA HIGH PRESSURE WILL STRENGTHEN OVER THE SOUTHEAST SUNDAY
THROUGH TUESDAY. A STRONG LOW PRESSURE SYSTEM MOVING EAST FROM THE
PLAINS WILL BRING A COLD FRONT TO THE AREA BY THURSDAY...WITH A
SIGNIFICANT COOLDOWN EXPECTED LATE WEEK INTO THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
AS OF 755 PM...A FADING BAND OF SHOWERS OVER EASTERN TN IS EXPECTED
TO ASH OUT NEAR THE NC/TN LINE OVER THE NEXT TWO HOURS. BASED ON
COVERAGE OF RAINFALL THIS AFTERNOON AND EVENING...CONDITIONS APPEAR
FAVORABLE FOR AT LEAST MVFR FOG TONIGHT. I WILL UPDATE THE FORECAST
TO ADJUST POPS AND INCREASE FOG MENTION.
AS OF 550 PM...WIDESPREAD CONVECTION HAS WEAKENED AND PUSHED EAST OF
THE FORECAST AREA. CONVECTION COVERAGE WILL REMAIN THE GREATEST OVER
THE EASTERN PIEDMONT OVER THE NEXT TWO HOURS...POSSIBLY FOLLOWED BY
THE ARRIVAL OF A LINE OF SHRA/TSRA NEAR THE NC/TN LINE. I WILL
UPDATE THE FORECAST TO ADJUST TO LATEST TRENDS. TEMPERATURES AND
DEWPOINTS WILL BE POPULATED WITH THE LATEST OBSERVATIONS.
AS OF 230 PM...AS EXPECTED...CONVECTION HAS EXPLODED ACRS THE
PIEDMONT FROM NE GA INTO THE SW NC PIEDMONT...WHERE CAPE VALUES OF
1500-2000 J/KG WERE ANALYZED BY THE LAPS. STORMS ARE REACHING
MARGINAL CORE HEIGHTS (55 DBZ NEAR 22 KFT) WHICH MAY BE ENUF TO
PRODUCE 1" HAIL AND DAMAGING WIND GUSTS. OVERALL...STILL EXPECT
MAINLY SUB-SEVERE STORMS AND SHOWERS WITH BRIEF TORRENTIAL DOWNPOURS
AND GUSTY WINDS. THE CELLS SEEM TO HAVE ENUF MOVEMENT TO LIMIT HEAVY
RAIN/FLOODING THREAT. CONVECTION SHUD WANE FAIRLY QUICKLY WITH LOSS
OF HEATING...AS ATMOSPHERE WILL BE WORKED OVER AND AN UPPER
SHORTWAVE WILL EXIT TO THE EAST.
OVERNIGHT...THE NAM AND GFS FCST SNDGS SHOW PLENTY OF MID LVL AND
UPR LVL DRYING BEHIND A PASSING SHORTWAVE...WHILE THE LLVLS REMAIN
MOIST. A COLD FRONT APPEARS TO WASH OUT TO THE NORTH OF THE
CWFA...SO WINDS WILL REMAIN LIGHT OR CALM AS WELL. GUIDANCE MAY BE
UNDERDONE ON FOG POTENTIAL. CERTAINLY IF SKIES CAN CLEAR EARLY
ENUF...THERE MAY BE AREAS OF FOG...POSSIBLY DENSE. TEMPS ARE FCST TO
FALL INTO THE 50S MTNS AND LWR 60S...WHICH IS WELL BELOW THE CURRENT
DWPTS.
SUNDAY...THE 500 MB HIGH BEGINS TO REASSERT ITSELF ACRS THE
SOUTHEAST STATES...WITH A BERMUDA HIGH TO THE EAST. OUR AREA SEEMS
TO BE IN BETWEEN THE BETTER MOISTURE TO SOUTH AND STRONGER
SUBSIDENCE AND DRIER AIR TO THE NORTH. THE NAM HAS PLENTY OF BL
MOISTURE ACRS THE AREA WITH A LIGHT SE FLOW. WHILE THE GFS IS ON
AVERAGE ABOUT 5 DEG LOWER OF DWPTS AND HAS A WEAK SW/W FLOW. THIS
RESULTS IN MORE CAPE ON THE NAM...ESP ACRS THE PIEDMONT.
HOWEVER...EVEN WITH THE INCREASED CAPE...THE NAM DOES NOT LOOK TOO
EXCITED ABOUT CONVECTION. I OPTED TO ONLY MAKE MINOR TWEAKS TO THE
POPS INHERITED FROM LAST NIGHT. STILL EXPECT AT LEAST ISOLD SHWRS
AND TSTMS...PERHAPS A LITTLE BETTER COVERAGE IN THE MTNS WHERE
DIFFERENTIAL MTN HEATING SHUD PROVIDE BEST TRIGGERING. TEMPS ARE
EXPECTED TO REBOUND INTO THE UPR 70S TO LWR 80S...AND MID 80S ACRS
THE PIEDMONT.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
AS OF 300 PM EDT SATURDAY...A PROMINENT 588 DM H5 RIDGE WILL BE IN
PLACE ACROSS THE SOUTHEAST ON MONDAY...WITH A HIGH AMPLITUDE PATTERN
FIRMLY IN PLACE BETWEEN A DEEP CENTRAL CONUS TROUGH AND EAST COAST
RIDGE BY TUE. DESPITE THE RIDGING AND RESULTANT MID LEVEL
INVERSION...PERSISTENT LOW LEVEL SRLY UPSLOPE FLOW SHOULD PROVIDE
TRIGGERING ACROSS THE MTNS. WILL THUS FEATURE MAINLY SCATTERED
DIURNAL CONVECTION MON AND TUE AFTN...WITH A FOCUS IN THE MTNS.
EXPECT WARM TEMPS THROUGH THE PERIOD.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
AS OF 300 PM EDT SATURDAY...UPPER DIVERGENCE AND IMPROVING SRLY FLOW
WILL AID CONVECTIVE COVERAGE STARTING WED...AND A MORE NON DIURNAL
NATURE IS EXPECTED GIVEN THE APPROACHING HIGH AMPLITUDE TROUGH AND
ASSOCIATED SURFACE FRONT. THE DEEPEST FORCING AND MOISTURE SHOULD
ARRIVE THU AS A BROAD AREA OF STRONG Q VECTOR CONVERGENCE CROSSES
THE REGION...ESPECIALLY DURING THE AFTN/EVENING HOURS. THIS COULD
LEAD TO STRONG TO SEVERE CONVECTION...BUT THE TIMING REMAINS
SOMEWHAT UNCERTAIN. IN ADDITION...MOST OF THE MODELS STILL DEPICT A
TROPICAL FEATURE MOVING NWD FROM THE FL COASTAL WATERS TO THE
CAROLINA COASTAL WATERS THU. THIS SHOULD REMAIN EAST OF THE AREA.
THE DEEP ERN TROUGH WILL PERSIST FRI THROUGH SAT...BUT WITH DRIER
AIR AND COOLER TEMPERATURES ARRIVING. ADDITIONAL ENERGY ROUNDING THE
TROUGH WILL BE HARD TO TIME...BUT THE BEST CONSENSUS FOR THE NEXT
VORT LOBE AND ASSOC MOISTURE APPEARS ON SAT...AND THERE MAY BE SOME
LOW LEVEL WAVE FORMATION ALONG A BAROCLINIC ZONE. WILL FEATURE LOW
END CHC GIVEN THE STEEP LAPSE RATES UNDER THE TROUGH.
&&
.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
AT KCLT...AT 2330Z...A HEAVY SHOWERS WAS PASSING JUST SOUTH OF THE
TERMINAL. IT APPEARS THAT ADDITIONAL LIGHT SHOWERS MAY PASS NEAR THE
TERMINAL THROUGH 1Z. I WILL INDICATE VCSH. OVERNIGHT...THE PRIMARY
CONCERN WILL BE THE POTENTIAL OF FOG...PROVIDED LIGHT TO CALM WINDS
AND WET SOIL. THE KCLT ASOS MEASURED A HALF INCH TODAY. AS A
RESULT...THE 21Z HRRR AND 18Z NAM12 INDICATE VERY LOW CONDENSATION
PRESSURE DEFICITS LATE TONIGHT INTO EARLY SUNDAY MORNING. I WILL
INDICATE IFR FOG DEVELOPING BY 6Z...DISSIPATING BY 13Z. SCT CU MAY
DEVELOP BY LATE MORNING...WITH LIGHT ENE WINDS.
ELSEWHERE...A FADING BAND OF SHOWERS OVER EASTERN TN IS EXPECTED TO
DISSIPATE NEAR THE NC/TN LINE OVER THE NEXT TWO HOURS. BASED ON
COVERAGE OF RAINFALL THIS AFTERNOON AND EVENING...CONDITIONS APPEAR
FAVORABLE FOR AT LEAST MVFR FOG TONIGHT. KAVL SHOULD REPEAT FOG
TIMING AS OBSERVED THIS MORNING...WITH LIFR BY 9Z. SCT CU MAY
DEVELOP BY LATE MORNING...WITH LIGHT ENE WINDS.
OUTLOOK...HIGH PRESSURE RETURNS ON MONDAY...BUT AFTERNOON AND
EVENING CONVECTION WILL BE POSSIBLE BOTH DAYS. WEDNESDAY AND
THURSDAY FEATURE A SLOW MOVING COLD FRONT...YIELDING A BETTER CHANCE
OF RESTRICTIONS IN PROLONGED PRECIPITATION.
CONFIDENCE TABLE...
00-06Z 06-12Z 12-18Z 18-24Z
KCLT HIGH 100% HIGH 97% HIGH 94% HIGH 100%
KGSP HIGH 100% HIGH 82% HIGH 91% HIGH 100%
KAVL HIGH 100% HIGH 88% HIGH 94% HIGH 100%
KHKY HIGH 100% MED 75% HIGH 95% HIGH 100%
KGMU HIGH 100% HIGH 90% HIGH 95% HIGH 100%
KAND HIGH 100% MED 68% HIGH 95% HIGH 100%
THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING
WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE
HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE
FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE)
WWW.WEATHER.GOV/GSP/AVIATION_TABLES
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...HG
NEAR TERM...ARK/NED
SHORT TERM...HG
LONG TERM...HG
AVIATION...NED
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1028 AM CDT FRI MAY 9 2014
.DISCUSSION...
RADAR COMPOSITES THIS MORNING SHOWING SHOWERS AND THUNDERSTORMS
PRETTY MUCH SURROUNDING THE FORECAST AREA...WITH CLUSTERS TO THE
NORTHEAST AND SOUTHWEST...AND SOME STRONG TO SEVERE CELLS OFF TO
THE WEST OF SAN ANTONIO. MORNING SOUNDINGS AND MODEL FORECAST
SOUNDING SUGGEST CURRENTLY WEAKLY CAPPED ATMOSPHERE SHOULD BECOME
UNSTABLE THIS AFTERNOON...ASSUMING CLOUD COVER ERODES AS EXPECTED AND
TEMPS RISE INTO THE MID 80S. SHOULD THAT MATERIALIZE...LOOKING AT
CAPE VALUES ABOVE 3000 J PER KG...ESPECIALLY NW ZONES. SHEAR
PROFILES SHOW ZERO TO 6 KM VALUES IN THE 20 TO 30 KNOT RANGE. WITH
MODERATE INSTABILITY AND SHEAR...AND DRIER AIR ALOFT...EXPECT
MULTICELLS LIKELY THE DOMINANT CONVECTIVE MODE...WITH SOME
POTENTIAL FOR ISOLATED DOWNBURST WINDS AND HAIL BEING THE MAIN
THREATS. LOW LEVEL SHEAR NOT VERY STRONG...SO TORNADOES NOT
LIKELY.
&&
.MARINE...
SE WINDS OF 10-15 KNOTS TODAY. TROPICAL TAP OF MOISTURE FROM THE
PACIFIC IS DRAPED OVER MEXICO AND THE COASTAL WATERS. THE NORTHERN
PERIPHERY OF THE MOISTURE MAY EXTEND OVER THE BAYS. THIS ABUNDANT
MOISTURE AND NOISY SW-WSW FLOW ALOFT SHOULD KEEP THE MARINE
ENVIRONMENT ACTIVE WITH SHOWERS AND THUNDERSTORMS TODAY...ESPECIALLY
IF ANY BREAKS FORM.
45
&&
.AVIATION...
CIGS GRADUALLY RISING WITH MOSTLY MVFR (1500-2000FT) AT 15Z THOUGH
CLL/UTS WERE VFR CIGS BUT STILL HAVE SOME HAZE. EXPECT THAT ACROSS
THE AREA WE WILL CONTINUE TO SEE CIGS RISE AND BREAKS DEVELOP SO BKN
TO SCT VFR CIGS CAN BE EXPECTED FOR HOU/IAH NORTHWARD BY 19Z...IF
NOT SOONER. GIVEN THE POOR MODEL CONSENSUS AND POOR INITIALIZATION
OF CONVECTION TO THE WEST ANY TIMING FOR ONSET OF SHRA/TSRA IN THE
SETX TERMINALS IS LOW CONFIDENCE. THOUGH THE ENVIRONMENT IS RIPE
THIS AFTERNOON PERHAPS PEAK HEATING AND THE ARRIVAL OF S/W NEAR DRT
MAY BE ENOUGH TO OVERCOME THE SMALL CAP THIS AFTERNOON. ANY THAT DO
FORM SHOULD BE CAPABLE OF STRONG GUSTY WINDS AND POSSIBLY AND CAN`T
RULE OUT SOME SMALL HAIL THOUGH THAT MAY BE CONFINED TO AREAS WEST
OF A BYY-CLL LINE.
45
.PREV DISCUSSION... /ISSUED 638 AM CDT FRI MAY 9 2014/
DISCUSSION...
SEE THE 12Z AVIATION DISCUSSION BELOW.
40
AVIATION...
IFR TO MVFR CONDITIONS ARE EXPECTED THROUGH MOST OF THE MORNING.
THE MODELS ARE INDICATING POSSIBLE VFR DURING THE MID OR LATE
AFTERNOON PERIOD. BEST CHANCES FOR SHOWERS OR THUNDERSTORMS WILL
BE AT KCLL AND KUTS. HOWEVER...GIVEN THE MOISTURE CHANNEL OVER THE
GULF...THERE IS A SLIGHT CHANCE OF SHOWERS FROM KHOU TO THE COAST
THROUGH 15Z. MAY AMEND IF MORE SHOWERS THAN EXPECTED DEVELOP.
THIS EVENING...MODEL SOUNDINGS INDICATE MVFR TO IFR CONDTIONS WILL
DEVELOP.
40
PREV DISCUSSION... /ISSUED 333 AM CDT FRI MAY 9 2014/
DISCUSSION...
AT 06Z...THERE WAS A WEAK AREA OF LOW PRESSURE OVER CENTRAL
OKLAHOMA AND ANOTHER WEAK AREA OF LOW PRESSURE NORTH OF DEL RIO.
SFC DEW PTS REMAIN IN THE LOWER 70S. RADAR IS A LITTLE MORE ACTIVE
THAN THE PAST FEW NIGHTS WITH A LINE OF STORMS DEVELOPING ACROSS
EXTREME SE TX FROM KBPT TO KGLS AND A SMALL CLUSTER NEAR KGRK.
WATER VAPOR IMAGERY SHOWS A WELL DEFINED S/WV IN EASTERN NEW
MEXICO AND THIS FEATURE WAS MOVING EAST AND WILL SERVE AS A
CATALYST FOR SHRA/TSRA OVER PARTS OF CENTRAL AND EASTERN TEXAS
TODAY. THE DISTURBANCE WILL APPROACH SE TX THIS AFTN AND FEEL IT
WILL TRIGGER TSRA OVER MAINLY THE WESTERN HALF OF THE CWA. NAM 12
SOUNDING FOR KCLL ARE VERY UNSTABLE WITH PWATS INCREASING FROM
1.38 THIS MORNING TO 1.79 THIS AFTN. CAPE VALUES EXCEED 3000 J/KG
AND LI`S DROP TO -9. SPC HAS OUTLOOKED THE WESTERN HALF OF SE TX
IN SLIGHT RISK AND SEE NO REASON TO DISAGREE. THE NAM...GFS AND
ECMWF ALL SHOW A SPEED MAX APPROACHING THIS AFTERNOON SO IT LOOKS
LIKE ALL THE INGREDIENTS ARE IN PLACE FOR SOME SEVERE WEATHER OVER
THE WESTERN ZONES. TOWARD THE HOUSTON AREA AND THE COAST...CAPPING
LOOKS TO REMAIN AN ISSUE AND PWATS ACTUALLY DROP THIS AFTN. WILL
MAINTAIN LOW END CHANCE POPS BUT SOUNDINGS LOOK MUCH LESS
FAVORABLE. THINGS SHOULD SETTLE DOWN QUICKLY TONIGHT WITH THE
LOSS OF HEATING. FWIW...THE HRRR INITIALIZED BEST THIS MORNING AND
HAVE LEANED TOWARD THIS SOLUTION FOR THE SHORT TERM.
VERY WARM AND HUMID CONDITIONS ARE EXPECTED OVER THE WEEKEND.
CAN`T RULE OUT ISOLATED SHOWERS WITH HEATING EACH DAY. PWATS
REMAIN AROUND 1.5-1.6 INCHES SO WILL MENTION A SLIGHT CHANCE OF
SHRAS EACH DAY.
THINGS BECOME A LITTLE MORE MUDDLED MON-WED. A DEEP UPPER LEVEL
TROUGH AND SURFACE COLD FRONT WILL APPROACH THE STATE ON MONDAY.
MODELS ARE IN GOOD AGREEMENT THROUGH MONDAY 12Z BUT DIVERGE
SIGNIFICANTLY THEREAFTER. GFS IS ABOUT 24-30 HOURS FASTER THAN THE
ECMWF. THE CANADIAN SUPPORTS THE SLOWER ECMWF. NOT REALLY SURE
HOW THINGS WILL EVENTUALLY TRANSPIRE THIS FAR OUT SO HAVE STARTED
POPS ON MONDAY AND WILL CARRY POPS THROUGH WEDNESDAY. AT THE
CURRENT TIME...FEEL TUESDAY WILL BE THE BEST DAY FOR RAIN CHANCES
BUT THAT IS SUBJECT TO CHANGE. HAVE RAISED RAIN CHANCES ON TUESDAY
TO 50 PERCENT. CONSIDERABLY COOLER AND DRIER CONDITIONS WILL
DEVELOP IN THE WAKE OF THE FRONT FOR THE SECOND HALF OF NEXT WEEK
WITH MIN TEMPS POSSIBLY FALLING BACK INTO THE 50S. 43
MARINE...
ONSHORE WINDS ARE EXPECTED THROUGH THE WEEKEND. WIND SPEEDS WILL BE
HIGH ENOUGH THIS MORNING FOR CAUTION CONDITIONS. MODERATE TO STRONG
ONSHORE WINDS ARE THEN EXPECTED TO DEVELOP SUNDAY NIGHT AS LOW
PRESSURE DEVELOPS OVER THE PLAINS. THE MODELS THEN DIFFERED ON THE
PASSAGE OF A COLD FRONT THROUGH SE TX AND OFF THE COAST. LIKED THE
SLOWER ECMWF.
40
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 86 69 88 71 88 / 30 30 10 10 10
HOUSTON (IAH) 86 71 87 73 87 / 40 20 20 10 20
GALVESTON (GLS) 81 73 82 73 82 / 40 20 20 10 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...46
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
638 AM CDT FRI MAY 9 2014
.DISCUSSION...
SEE THE 12Z AVIATION DISCUSSION BELOW.
40
&&
.AVIATION...
IFR TO MVFR CONDITIONS ARE EXPECTED THROUGH MOST OF THE MORNING.
THE MODELS ARE INDICATING POSSIBLE VFR DURING THE MID OR LATE
AFTERNOON PERIOD. BEST CHANCES FOR SHOWERS OR THUNDERSTORMS WILL
BE AT KCLL AND KUTS. HOWEVER...GIVEN THE MOISTURE CHANNEL OVER THE
GULF...THERE IS A SLIGHT CHANCE OF SHOWERS FROM KHOU TO THE COAST
THROUGH 15Z. MAY AMEND IF MORE SHOWERS THAN EXPECTED DEVELOP.
THIS EVENING...MODEL SOUNDINGS INDICATE MVFR TO IFR CONDTIONS WILL
DEVELOP.
40
&&
.PREV DISCUSSION... /ISSUED 333 AM CDT FRI MAY 9 2014/
DISCUSSION...
AT 06Z...THERE WAS A WEAK AREA OF LOW PRESSURE OVER CENTRAL
OKLAHOMA AND ANOTHER WEAK AREA OF LOW PRESSURE NORTH OF DEL RIO.
SFC DEW PTS REMAIN IN THE LOWER 70S. RADAR IS A LITTLE MORE ACTIVE
THAN THE PAST FEW NIGHTS WITH A LINE OF STORMS DEVELOPING ACROSS
EXTREME SE TX FROM KBPT TO KGLS AND A SMALL CLUSTER NEAR KGRK.
WATER VAPOR IMAGERY SHOWS A WELL DEFINED S/WV IN EASTERN NEW
MEXICO AND THIS FEATURE WAS MOVING EAST AND WILL SERVE AS A
CATALYST FOR SHRA/TSRA OVER PARTS OF CENTRAL AND EASTERN TEXAS
TODAY. THE DISTURBANCE WILL APPROACH SE TX THIS AFTN AND FEEL IT
WILL TRIGGER TSRA OVER MAINLY THE WESTERN HALF OF THE CWA. NAM 12
SOUNDING FOR KCLL ARE VERY UNSTABLE WITH PWATS INCREASING FROM
1.38 THIS MORNING TO 1.79 THIS AFTN. CAPE VALUES EXCEED 3000 J/KG
AND LI`S DROP TO -9. SPC HAS OUTLOOKED THE WESTERN HALF OF SE TX
IN SLIGHT RISK AND SEE NO REASON TO DISAGREE. THE NAM...GFS AND
ECMWF ALL SHOW A SPEED MAX APPROACHING THIS AFTERNOON SO IT LOOKS
LIKE ALL THE INGREDIENTS ARE IN PLACE FOR SOME SEVERE WEATHER OVER
THE WESTERN ZONES. TOWARD THE HOUSTON AREA AND THE COAST...CAPPING
LOOKS TO REMAIN AN ISSUE AND PWATS ACTUALLY DROP THIS AFTN. WILL
MAINTAIN LOW END CHANCE POPS BUT SOUNDINGS LOOK MUCH LESS
FAVORABLE. THINGS SHOULD SETTLE DOWN QUICKLY TONIGHT WITH THE
LOSS OF HEATING. FWIW...THE HRRR INITIALIZED BEST THIS MORNING AND
HAVE LEANED TOWARD THIS SOLUTION FOR THE SHORT TERM.
VERY WARM AND HUMID CONDITIONS ARE EXPECTED OVER THE WEEKEND.
CAN`T RULE OUT ISOLATED SHOWERS WITH HEATING EACH DAY. PWATS
REMAIN AROUND 1.5-1.6 INCHES SO WILL MENTION A SLIGHT CHANCE OF
SHRAS EACH DAY.
THINGS BECOME A LITTLE MORE MUDDLED MON-WED. A DEEP UPPER LEVEL
TROUGH AND SURFACE COLD FRONT WILL APPROACH THE STATE ON MONDAY.
MODELS ARE IN GOOD AGREEMENT THROUGH MONDAY 12Z BUT DIVERGE
SIGNIFICANTLY THEREAFTER. GFS IS ABOUT 24-30 HOURS FASTER THAN THE
ECMWF. THE CANADIAN SUPPORTS THE SLOWER ECMWF. NOT REALLY SURE
HOW THINGS WILL EVENTUALLY TRANSPIRE THIS FAR OUT SO HAVE STARTED
POPS ON MONDAY AND WILL CARRY POPS THROUGH WEDNESDAY. AT THE
CURRENT TIME...FEEL TUESDAY WILL BE THE BEST DAY FOR RAIN CHANCES
BUT THAT IS SUBJECT TO CHANGE. HAVE RAISED RAIN CHANCES ON TUESDAY
TO 50 PERCENT. CONSIDERABLY COOLER AND DRIER CONDITIONS WILL
DEVELOP IN THE WAKE OF THE FRONT FOR THE SECOND HALF OF NEXT WEEK
WITH MIN TEMPS POSSIBLY FALLING BACK INTO THE 50S. 43
MARINE...
ONSHORE WINDS ARE EXPECTED THROUGH THE WEEKEND. WIND SPEEDS WILL BE
HIGH ENOUGH THIS MORNING FOR CAUTION CONDITIONS. MODERATE TO STRONG
ONSHORE WINDS ARE THEN EXPECTED TO DEVELOP SUNDAY NIGHT AS LOW
PRESSURE DEVELOPS OVER THE PLAINS. THE MODELS THEN DIFFERED ON THE
PASSAGE OF A COLD FRONT THROUGH SE TX AND OFF THE COAST. LIKED THE
SLOWER ECMWF.
40
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 86 69 88 71 88 / 50 30 10 10 10
HOUSTON (IAH) 86 71 87 73 87 / 30 20 20 10 20
GALVESTON (GLS) 81 73 82 73 82 / 30 20 20 10 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
DISCUSSION...43
AVIATION/MARINE...40
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
333 AM CDT FRI MAY 9 2014
.DISCUSSION...
AT 06Z...THERE WAS A WEAK AREA OF LOW PRESSURE OVER CENTRAL
OKLAHOMA AND ANOTHER WEAK AREA OF LOW PRESSURE NORTH OF DEL RIO.
SFC DEW PTS REMAIN IN THE LOWER 70S. RADAR IS A LITTLE MORE ACTIVE
THAN THE PAST FEW NIGHTS WITH A LINE OF STORMS DEVELOPING ACROSS
EXTREME SE TX FROM KBPT TO KGLS AND A SMALL CLUSTER NEAR KGRK.
WATER VAPOR IMAGERY SHOWS A WELL DEFINED S/WV IN EASTERN NEW
MEXICO AND THIS FEATURE WAS MOVING EAST AND WILL SERVE AS A
CATALYST FOR SHRA/TSRA OVER PARTS OF CENTRAL AND EASTERN TEXAS
TODAY. THE DISTURBANCE WILL APPROACH SE TX THIS AFTN AND FEEL IT
WILL TRIGGER TSRA OVER MAINLY THE WESTERN HALF OF THE CWA. NAM 12
SOUNDING FOR KCLL ARE VERY UNSTABLE WITH PWATS INCREASING FROM
1.38 THIS MORNING TO 1.79 THIS AFTN. CAPE VALUES EXCEED 3000 J/KG
AND LI`S DROP TO -9. SPC HAS OUTLOOKED THE WESTERN HALF OF SE TX
IN SLIGHT RISK AND SEE NO REASON TO DISAGREE. THE NAM...GFS AND
ECMWF ALL SHOW A SPEED MAX APPROACHING THIS AFTERNOON SO IT LOOKS
LIKE ALL THE INGREDIENTS ARE IN PLACE FOR SOME SEVERE WEATHER OVER
THE WESTERN ZONES. TOWARD THE HOUSTON AREA AND THE COAST...CAPPING
LOOKS TO REMAIN AN ISSUE AND PWATS ACTUALLY DROP THIS AFTN. WILL
MAINTAIN LOW END CHANCE POPS BUT SOUNDINGS LOOK MUCH LESS
FAVORABLE. THINGS SHOULD SETTLE DOWN QUICKLY TONIGHT WITH THE
LOSS OF HEATING. FWIW...THE HRRR INITIALIZED BEST THIS MORNING AND
HAVE LEANED TOWARD THIS SOLUTION FOR THE SHORT TERM.
VERY WARM AND HUMID CONDITIONS ARE EXPECTED OVER THE WEEKEND.
CAN`T RULE OUT ISOLATED SHOWERS WITH HEATING EACH DAY. PWATS
REMAIN AROUND 1.5-1.6 INCHES SO WILL MENTION A SLIGHT CHANCE OF
SHRAS EACH DAY.
THINGS BECOME A LITTLE MORE MUDDLED MON-WED. A DEEP UPPER LEVEL
TROUGH AND SURFACE COLD FRONT WILL APPROACH THE STATE ON MONDAY.
MODELS ARE IN GOOD AGREEMENT THROUGH MONDAY 12Z BUT DIVERGE
SIGNIFICANTLY THEREAFTER. GFS IS ABOUT 24-30 HOURS FASTER THAN THE
ECMWF. THE CANADIAN SUPPORTS THE SLOWER ECMWF. NOT REALLY SURE
HOW THINGS WILL EVENTUALLY TRANSPIRE THIS FAR OUT SO HAVE STARTED
POPS ON MONDAY AND WILL CARRY POPS THROUGH WEDNESDAY. AT THE
CURRENT TIME...FEEL TUESDAY WILL BE THE BEST DAY FOR RAIN CHANCES
BUT THAT IS SUBJECT TO CHANGE. HAVE RAISED RAIN CHANCES ON TUESDAY
TO 50 PERCENT. CONSIDERABLY COOLER AND DRIER CONDITIONS WILL
DEVELOP IN THE WAKE OF THE FRONT FOR THE SECOND HALF OF NEXT WEEK
WITH MIN TEMPS POSSIBLY FALLING BACK INTO THE 50S. 43
&&
.MARINE...
ONSHORE WINDS ARE EXPECTED THROUGH THE WEEKEND. WIND SPEEDS WILL BE
HIGH ENOUGH THIS MORNING FOR CAUTION CONDITIONS. MODERATE TO STRONG
ONSHORE WINDS ARE THEN EXPECTED TO DEVELOP SUNDAY NIGHT AS LOW
PRESSURE DEVELOPS OVER THE PLAINS. THE MODELS THEN DIFFERED ON THE
PASSAGE OF A COLD FRONT THROUGH SE TX AND OFF THE COAST. LIKED THE
SLOWER ECMWF.
40
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 86 69 88 71 88 / 50 30 10 10 10
HOUSTON (IAH) 86 71 87 73 87 / 30 20 20 10 20
GALVESTON (GLS) 81 73 82 73 82 / 30 20 20 10 20
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 5 AM CDT EARLY THIS
MORNING FOR THE FOLLOWING ZONES: WATERS FROM FREEPORT TO
THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM
FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS
FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
&&
$$
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
655 PM EDT FRI MAY 9 2014
.SYNOPSIS...
A FRONTAL BOUNDARY WILL BE MOVING TOWARD THE CENTRAL APPALACHIANS
SATURDAY...ORIENTING ITSELF WEST TO EAST ACROSS THE OHIO VALLEY TO
MID ATLANTIC SUNDAY. RIDGE BUILDS SUNDAY INTO MONDAY SENDING THIS
FRONT NORTH. A STRONGER COLD FRONT ARRIVES IN THE WEDNESDAY TIME
FRAME...SLOWING DOWN AS IT MOVES EAST OF THE APPALACHIANS INTO
LATE WEEK.
&&
.NEAR TERM /THROUGH SATURDAY/...
AS OF 645 PM EDT FRIDAY...
COVERAGE OF SHOWERS HAD FILLED IN OVER MUCH OF THE FORECAST AREA
THIS EVENING. HAVE INCREASED PROBABILITY OF SHOWERS BASED ON RADARTRENDS.
LIGHTNING ACTIVITY HAS BEEN CONFINED TO JUST SOUTH OF THE COUNTY
WARNING AREA...BUT ISOLATED THUNDERSTORMS ARE STILL
POSSIBLE...ESPECIALLY SOUTH AND EAST OF DANVILLE.
SHORTWAVE ENERGY ACROSS TN PER LATEST RAP MODEL SHOULD HEAD NE INTO
THE CENTRAL APPALACHIANS BY DUSK WITH INCREASED THREAT OF SHOWERS
AND STORMS IN THE WESTERN CWA. INSTABILITY IN THE EAST IS HIGHER PER
MORE SUN EARLIER RAISING SBCAPES TO 500-1000 J/KG...WITH DCAPES OVER
1000 J/KG GIVEN DRIER AIR IN THE LOW LVLS. SOME OF THE SHOWERS OR
STORMS COULD PRODUCE GUSTY WINDS BUT OVERALL WIND ENERGY IS WEAK
COMPARED TO THE WRN OHIO VALLEY.
THE THREAT OF SHOWERS WILL DIMINISH AFTER MIDNIGHT THOUGH ENOUGH LOW
LVL CONVERGENCE WITH SW FLOW ALOFT AND APPROACHING FRONT INTO THE
OHIO VALLEY TO KEEP SOME CHANCE IN OVER THE MTNS OVERNIGHT.
MODELS SHOWING SHORTWAVE PUSHING NE ACROSS CENTRAL NC OVERNIGHT
WHICH COULD PRODUCE A SHOWER OR TWO OUT EAST. THE BETTER THREAT
ARRIVES ACROSS THE REGION SATURDAY AND ESPECIALLY CLOSER TO THE
FRONT AND UPPER SUPPORT PUSHING ACROSS THE OHIO VALLEY INTO MID
ATLANTIC. KEPT POPS IN THE LIKELY RANGE MAINLY WEST OF I-81 IN
VIRGINIA...AND ACROSS THE NC MTNS TO LOWER CHANCES IN THE PIEDMONT.
WITH PLENTY OF CLOUDS TONIGHT....AND HUMIDITY INCREASING...TEMPS
SHOULD DROP INTO THE MID TO UPPER 50S MOUNTAINS TO LOWER TO MID 60S
EAST.
SATURDAY WILL BE COOLER WITH PLENTY OF CLOUD COVER. SOME SUNSHINE
COULD BREAK OUT ACROSS THE EAST IN THE AFTERNOON. OVERALL LOOKING AT
HIGHS FROM THE LOWER 70S MOUNTAINS TO NEAR 80 EAST.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
AS OF 200 PM EDT FRIDAY...
WEAK BOUNDARY SETTLES NEAR THE REGION SATURDAY...WITH UPPER LEVEL
DISTURBANCES/JET STREAK ADDING TO LIFT. MOST OF THE SHOWERS AND
STORMS WILL BE DIURNAL IN NATURE AND ENDING SATURDAY NIGHT.
SUMMERLIKE PATTERN CONTINUES THROUGH THE WEEKEND WITH LESS COVERAGE
ON SUNDAY...BUT STILL LATE DAY STORMS IN THE WEST WITH SURFACE
CONVERGENCE ALONG THE MOUNTAINS. EVEN LESS OF A CHANCE ON MONDAY AS
RIDGE BUILDS AND HEIGHTS RISE SLIGHTLY...WASHING OUT OR PUSHING
NORTH WHATEVER BOUNDARY REMAINS FROM THE WEEKEND. MAX T WILL BE
HIGHLY DEPENDENT ON WHAT SITES GET HIT WITH STORMS...BUT H85 TEMPS
WILL RISE BACK FROM 16-18C SUNDAY AND MONDAY...AFTER SOMEWHAT COOLER
VALUES ON SATURDAY.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 200 PM EDT FRIDAY...
PHASED FULL LATITUDE TROUGH DEVELOPING ALONG THE CONTINENTAL DIVIDE
ON MONDAY...WILL MOVE EAST AND LOOKS TO BE FORMIDABLE ENOUGH TO
DISLODGE THE STRONG UPPER RIDGE AND CHANGE THE PATTERN THROUGH THE
MIDDLE ATLANTIC AND SOUTHEAST. WEDNESDAY NIGHT LOOKS TO BE THE BEST
TIMEFRAME FOR THE STRONG COLD FRONT ASSOCIATED WITH THIS TROUGH TO
CROSS OUR REGION...WITH MORE WIDESPREAD STORMS LATE WED AND WED
NIGHT. WITH THE UPPER RIDGE NEARLY CLOSED OFF OVERHEAD ON
TUESDAY...CHCS OF STORMS MAY BE THE SMALLEST THAT DAY...ALTHOUGH
STILL CAN`T RULE OUT ISOLATED THUNDERSTORMS ANCHORED TO THE HIGHEST
PEAKS...ESPECIALLY WESTERN GREENBRIER. H85 TEMPS MAY FALL TO 5C
ACROSS THE REGION BY LATE WEEK BEHIND THE FRONT...WHICH WILL BE
QUITE AN IMPRESSIVE COOL DOWN CONSIDERING THE STRING OF 80F HIGHS
EXPECTED THIS WEEKEND AND MUCH OF THE UPCOMING WEEK. THE AIRMASS IS
SO COLD ALOFT THAT THERE MAY BE SOME INSTABILITY SHOWERS IN THE
AFTERNOON LATE WEEK OR NEXT WEEKEND...WITH THE MODELS TYPICALLY POOR
AT PREDICTING QPF THIS MANY DAYS AWAY IN THIS SETUP.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
AS OF 140 PM EDT FRIDAY...
WILL EXPERIENCE VFR CONDITIONS THROUGH THE AFTERNOON INTO THE
EVENING. ISOLATED TO SCATTERED SHOWERS ALONG WITH A THUNDERSTORM
COULD IMPACT BCB/BLF/LWB THIS AFTERNOON INTO ROANOKE LATE
AFTERNOON. CONFIDENCE NOT HIGH ENOUGH FOR PREDOMINANT THUNDER...AS
INSTABILITY AND COVERAGE NOT ALL THAT HIGH.
ISSUE TONIGHT WILL BE THE COVERAGE OF RAIN SHOWERS AND EFFECT ON
CIGS AND VSBYS. ATTM...MODELS AND FORECAST SOUNDINGS SUGGEST
LIMITED THREAT OF SUB VFR CIGS/VSBYS THOUGH MOISTENING OF THE
AIRMASS MAY FAVOR SOME FOG IN THE VALLEYS AROUND BCB/LWB/DAN. WILL
LEAVE OUT FOR NOW. SHOULD BE A LULL IN PRECIP OVERNIGHT.
FRONT APPEARS TO BE STAYING NORTHWEST OF US INTO SATURDAY AS UPPER
LEVELS ENERGY SHEARS OUT TO THE NORTHEAST. WILL SEE SCATTERED
TO NUMEROUS COVERAGE ACROSS BY LATE SAT MORNING INTO THE AFTERNOON
MAINLY WEST OF THE BLUE RIDGE.
GUSTY SW WINDS THIS AFTERNOON TAPER OFF THIS EVENING THEN KICK UP
AGAIN LATE SAT MORNING...GENERALLY GUSTS AROUND 15-25 KNOTS.
LIKELIHOOD FOR SUB-VFR AT TIMES SATURDAY AFTERNOON WITH SHRA/TSRA
AHEAD OF THE FRONT MOVING SLOWLY EAST AND DEEPER MOISTURE IN
PLACE. BOUNDARY MAY WASH OUT UPON CROSSING THE AREA OR STALL JUST
OFF TO THE WEST BY SUNDAY WITH MAINLY VFR CONDITIONS EXPECTED
OUTSIDE OF OCNL MVFR IN MAINLY ISOLATED MOUNTAIN SHOWERS AS
LEFTOVER MOISTURE APPEARS QUITE SHALLOW. RIDGE OFFSHORE
STRENGTHENS AGAIN ON MONDAY AHEAD OF ANOTHER FRONT TO THE WEST
WITH MAINLY VFR EXCLUDING PERHAPS BRIEF MVFR IN A LATE DAY SHRA
ESPCLY MOUNTAINS. THIS COLD FRONT APPROACHES FROM THE WEST TUESDAY
WITH MOISTURE INCREASING AND CIGS LOWERING TOWARD MVFR LEVELS
ESPCLY LATER IN THE DAY WHEN A FEW BANDS OF SHOWERS APPEAR
POSSIBLE.
&&
.CLIMATE...
HERE ARE THE RECORDS FOR MAY 9TH AND OBSERVED HIGHS THROUGH 5PM.
STATION RECORD/YEAR OBSERVED HIGH
ROA 92/1963 88
LYH 94/1936 88
DAN 94/1963 89
BCB 85/1966 81
BLF 84/2005 84 **TIED FOR MAY 9TH**
LWB 82/2000 80
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...RAB/WP
NEAR TERM...AMS/WP
SHORT TERM...KM
LONG TERM...KM
AVIATION...RAB/WP
CLIMATE...WP/AMS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
334 PM EDT FRI MAY 9 2014
.SYNOPSIS...
A FRONTAL BOUNDARY WILL BE MOVING TOWARD THE CENTRAL APPALACHIANS
SATURDAY...ORIENTING ITSELF WEST TO EAST ACROSS THE OHIO VALLEY TO
MID ATLANTIC SUNDAY. RIDGE BUILDS SUNDAY INTO MONDAY SENDING THIS
FRONT NORTH. A STRONGER COLD FRONT ARRIVES IN THE WEDNESDAY TIME
FRAME...SLOWING DOWN AS IT MOVES EAST OF THE APPALACHIANS INTO
LATE WEEK.
&&
.NEAR TERM /THROUGH SATURDAY/...
AS OF 315 PM EDT FRIDAY...
A FEW SHOWERS AND STORMS POPPING UP AS FORECASTED BY THE HIGH-RES
MODELS ACROSS THE NC MTNS INTO THE NEW RIVER VALLEY OF VA AND SE WV.
ANOTHER NARROW PATCH ALSO OCCURRING FROM INT-WEST OF CLT.
SHORTWAVE ENERGY ACROSS TN PER LATEST RAP MODEL SHOULD HEAD NE INTO
THE CENTRAL APPALACHIANS BY DUSK WITH INCREASED THREAT OF SHOWERS
AND STORMS IN THE WESTERN CWA. INSTABILITY IN THE EAST IS HIGHER PER
MORE SUN EARLIER RAISING SBCAPES TO 500-1000 J/KG...WITH DCAPES OVER
1000 J/KG GIVEN DRIER AIR IN THE LOW LVLS. SOME OF THE SHOWERS OR
STORMS COULD PRODUCE GUSTY WINDS BUT OVERALL WIND ENERGY IS WEAK
COMPARED TO FURTHER ACROSS THE WRN OHIO VALLEY.
THE THREAT OF SHOWERS WILL DIMINISH AFTER MIDNIGHT THOUGH ENOUGH LOW
LVL CONVERGENCE WITH SW FLOW ALOFT AND APPROACHING FRONT INTO THE
OHIO VALLEY TO KEEP SOME CHANCE IN OVER THE MTNS OVERNIGHT.
MODELS SHOWING SHORTWAVE PUSHING NE ACROSS CENTRAL NC OVERNIGHT
WHICH COULD PRODUCE A SHOWER OR TWO OUT EAST. THE BETTER THREAT
ARRIVES ACROSS THE REGION SATURDAY AND ESPECIALLY CLOSER TO THE
FRONT AND UPPER SUPPORT PUSHING ACROSS THE OHIO VALLEY INTO MID
ATLANTIC. KEPT POPS IN THE LIKELY RANGE MAINLY WEST OF I-81 IN
VIRGINIA...AND ACROSS THE NC MTNS TO LOWER CHANCES IN THE PIEDMONT.
WITH PLENTY OF CLOUDS TONIGHT....AND HUMIDITY INCREASING...TEMPS
SHOULD DROP INTO THE MID TO UPPER 50S MOUNTAINS TO LOWER TO MID 60S
EAST.
SATURDAY WILL BE COOLER WITH PLENTY OF CLOUD COVER. SOME SUNSHINE
COULD BREAK OUT ACROSS THE EAST IN THE AFTERNOON. OVERALL LOOKING AT
HIGHS FROM THE LOWER 70S MOUNTAINS TO NEAR 80 EAST.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
AS OF 200 PM EDT FRIDAY...
WEAK BOUNDARY SETTLES NEAR THE REGION SATURDAY...WITH UPPER LEVEL
DISTURBANCES/JET STREAK ADDING TO LIFT. MOST OF THE SHOWERS AND
STORMS WILL BE DIURNAL IN NATURE AND ENDING SATURDAY NIGHT.
SUMMERLIKE PATTERN CONTINUES THROUGH THE WEEKEND WITH LESS COVERAGE
ON SUNDAY...BUT STILL LATE DAY STORMS IN THE WEST WITH SURFACE
CONVERGENCE ALONG THE MOUNTAINS. EVEN LESS OF A CHANCE ON MONDAY AS
RIDGE BUILDS AND HEIGHTS RISE SLIGHTLY...WASHING OUT OR PUSHING
NORTH WHATEVER BOUNDARY REMAINS FROM THE WEEKEND. MAX T WILL BE
HIGHLY DEPENDENT ON WHAT SITES GET HIT WITH STORMS...BUT H85 TEMPS
WILL RISE BACK FROM 16-18C SUNDAY AND MONDAY...AFTER SOMEWHAT COOLER
VALUES ON SATURDAY.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 200 PM EDT FRIDAY...
PHASED FULL LATITUDE TROUGH DEVELOPING ALONG THE CONTINENTAL DIVIDE
ON MONDAY...WILL MOVE EAST AND LOOKS TO BE FORMIDABLE ENOUGH TO
DISLODGE THE STRONG UPPER RIDGE AND CHANGE THE PATTERN THROUGH THE
MIDDLE ATLANTIC AND SOUTHEAST. WEDNESDAY NIGHT LOOKS TO BE THE BEST
TIMEFRAME FOR THE STRONG COLD FRONT ASSOCIATED WITH THIS TROUGH TO
CROSS OUR REGION...WITH MORE WIDESPREAD STORMS LATE WED AND WED
NIGHT. WITH THE UPPER RIDGE NEARLY CLOSED OFF OVERHEAD ON
TUESDAY...CHCS OF STORMS MAY BE THE SMALLEST THAT DAY...ALTHOUGH
STILL CAN`T RULE OUT ISOLATED THUNDERSTORMS ANCHORED TO THE HIGHEST
PEAKS...ESPECIALLY WESTERN GREENBRIER. H85 TEMPS MAY FALL TO 5C
ACROSS THE REGION BY LATE WEEK BEHIND THE FRONT...WHICH WILL BE
QUITE AN IMPRESSIVE COOL DOWN CONSIDERING THE STRING OF 80F HIGHS
EXPECTED THIS WEEKEND AND MUCH OF THE UPCOMING WEEK. THE AIRMASS IS
SO COLD ALOFT THAT THERE MAY BE SOME INSTABILITY SHOWERS IN THE
AFTERNOON LATE WEEK OR NEXT WEEKEND...WITH THE MODELS TYPICALLY POOR
AT PREDICTING QPF THIS MANY DAYS AWAY IN THIS SETUP.
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
AS OF 140 PM EDT FRIDAY...
WILL EXPERIENCE VFR CONDITIONS THROUGH THE AFTERNOON INTO THE
EVENING. ISOLATED TO SCATTERED SHOWERS ALONG WITH A THUNDERSTORM
COULD IMPACT BCB/BLF/LWB THIS AFTERNOON INTO ROANOKE LATE
AFTERNOON. CONFIDENCE NOT HIGH ENOUGH FOR PREDOMINANT THUNDER...AS
INSTABILITY AND COVERAGE NOT ALL THAT HIGH.
ISSUE TONIGHT WILL BE THE COVERAGE OF RAIN SHOWERS AND EFFECT ON
CIGS AND VSBYS. ATTM...MODELS AND FORECAST SOUNDINGS SUGGEST
LIMITED THREAT OF SUB VFR CIGS/VSBYS THOUGH MOISTENING OF THE
AIRMASS MAY FAVOR SOME FOG IN THE VALLEYS AROUND BCB/LWB/DAN. WILL
LEAVE OUT FOR NOW. SHOULD BE A LULL IN PRECIP OVERNIGHT.
FRONT APPEARS TO BE STAYING NORTHWEST OF US INTO SATURDAY AS UPPER
LEVELS ENERGY SHEARS OUT TO THE NORTHEAST. WILL SEE SCATTERED
TO NUMEROUS COVERAGE ACROSS BY LATE SAT MORNING INTO THE AFTERNOON
MAINLY WEST OF THE BLUE RIDGE.
GUSTY SW WINDS THIS AFTERNOON TAPER OFF THIS EVENING THEN KICK UP
AGAIN LATE SAT MORNING...GENERALLY GUSTS AROUND 15-25 KNOTS.
LIKELIHOOD FOR SUB-VFR AT TIMES SATURDAY AFTERNOON WITH SHRA/TSRA
AHEAD OF THE FRONT MOVING SLOWLY EAST AND DEEPER MOISTURE IN
PLACE. BOUNDARY MAY WASH OUT UPON CROSSING THE AREA OR STALL JUST
OFF TO THE WEST BY SUNDAY WITH MAINLY VFR CONDITIONS EXPECTED
OUTSIDE OF OCNL MVFR IN MAINLY ISOLATED MOUNTAIN SHOWERS AS
LEFTOVER MOISTURE APPEARS QUITE SHALLOW. RIDGE OFFSHORE
STRENGTHENS AGAIN ON MONDAY AHEAD OF ANOTHER FRONT TO THE WEST
WITH MAINLY VFR EXCLUDING PERHAPS BRIEF MVFR IN A LATE DAY SHRA
ESPCLY MOUNTAINS. THIS COLD FRONT APPROACHES FROM THE WEST TUESDAY
WITH MOISTURE INCREASING AND CIGS LOWERING TOWARD MVFR LEVELS
ESPCLY LATER IN THE DAY WHEN A FEW BANDS OF SHOWERS APPEAR
POSSIBLE.
&&
.CLIMATE...
ANOTHER VERY WARM DAY ALREADY. CLOUDS AND SHOWERS MAY LIMIT TEMPS
FROM RISING MUCH MORE IN THE WEST BUT STILL POSSIBILITY EXISTS FOR
RECORD HIGHS AT BLF/BCB/LWB. HERE ARE THE RECORDS FOR MAY 9TH AND
CURRENT FORECAST HIGHS.
STATION CURRENT RECORD/YEAR FORECAST HIGH
ROA 92/1963 87
LYH 94/1936 88
DAN 94/1963 90
BCB 85/1966 84
BLF 84/2005 84
LWB 82/2000 83
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...RAB/WP
NEAR TERM...WP
SHORT TERM...KM
LONG TERM...KM
AVIATION...RAB/WP
CLIMATE...WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
148 PM EDT FRI MAY 9 2014
.SYNOPSIS...
HIGH PRESSURE NOW OVER THE SOUTHEAST COAST WILL PUMP MOISTURE UP
OUR WAY THIS AFTERNOON IN ADVANCE OF A FRONT. THIS SYSTEM HEADS
OUT BY SATURDAY NIGHT WITH ANOTHER UPPER HIGH MOVING IN FOR SUNDAY
AND MONDAY. A STRONG FRONT ARRIVES IN THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /THROUGH SATURDAY/...
AS OF 1220 PM EDT FRIDAY...
CU FIELD INCREASING OVER THE AREA...WITH SOME VERTICAL EXTENT TO
SOME. LATEST RUC MESOANLYSIS PER SPC PAGE SHOWING SBCAPES ABOVE
500 J/KG OVER THE SOUTHEAST BUT REMAINING LOWER IN THE MOUNTAINS.
HIGH-RES MODELS SHOW SHOWERS DEVELOPING ACROSS THE SRN BLUE RIDGE
INTO THE WV MTNS THROUGH MID AFTERNOON WITH BETTER COVERAGE OVER
THE MOUNTAINS AFTER 4-5 PM AS MID LEVEL VORT MOVES FROM TN TO THE
CENTRAL APPALACHIANS. WILL KEEP POPS IN THE CHANCE RANGE...HIGHER
IN THE FAR WEST. EXPECTING LESS THREAT IN THE EAST ALTHOUGH GIVEN
WARMER TEMPS...ISOLATED THUNDERSTORMS ARE POSSIBLE AFTER 4 PM.
RAISED HIGHS...MAINLY EAST OF THE BLUE RIDGE AS MORE SUNSHINE
OCCURRING AND TEMPS WERE ALREADY RUNNING ABOUT 3-6 DEGREES WARMER
THAN FORECAST AT NOON. SO LOOKING AT AROUND 90 SOUTHSIDE VA/NW NC
PIEDMONT. RECORDS ARE POSSIBLE MAINLY THE MOUNTAINS. SEE CLIMATE
SECTION BELOW. AS THE SHOWERS AND STORMS FORM...EXPECT TEMPS TO
COOL SOME.
PREVIOUS VALID DISCUSSION...
FOCUS THROUGH THE NEAR TERM WILL BE ON INCREASING CHANCES FOR
CONVECTION INTO SATURDAY ASSOCIATED WITH AN APPROACHING COLD
FRONT AND UPPER TROUGH. THE UPPER TROUGH...THE SAME ONE THAT HAS
ASSOCIATED WITH MORE WIDESPREAD SEVERE THUNDERSTORMS IN THE
MIDWEST/SOUTHERN PLAINS...WILL SHIFT NORTHEASTWARD TOWARD THE
GREAT LAKES AND WEAKEN/SHEAR OUT CONSIDERABLY AS IT APPROACHES THE
MID-ATLANTIC AND THE UPPER RIDGE IN PLACE ALONG THE EAST COAST.
THE BROOKS-CRAVEN SIGNIFICANT SVR PARAMETER...SUGGESTS THAT THE
THREAT FOR THUNDERSTORMS LATE THIS AFTERNOON/EVENING IS MARGINAL
AT BEST...WITH MOST VALUES 5000 OR LESS.
AS THE UPPER TROUGH MOVES ACROSS THE REGION OVERNIGHT/EARLY SAT
AND THE LOW-LEVEL AIR MASS CONTINUES TO MOISTEN...EXPECT SCATTERED
SHOWERS TO CONTINUE OVERNIGHT/EARLY SAT...ESPECIALLY WEST OF THE
BLUE RIDGE WHERE THE BEST FORCING WILL REMAIN. SATURDAY...THE
ENTIRE CWA REMAINS UNDER AN INCREASINGLY MOIST/MARGINALLY UNSTABLE
AIR MASS WITH CONSIDERABLE CONVECTIVE DEBRIS IN PLACE. THE MAIN
UPPER SUPPORT HAS PASSED BY TO THE NORTH...BUT BROAD WSW
FLOW/TROUGHING REMAINS IN PLACE ACROSS MUCH OF THE U.S. WEAK
SUBTLE IMPULSES EMBEDDED WITHIN THE UPPER FLOW WILL IMPINGE ON THE
MORE UNSTABLE/MOIST ATMOSPHERE...PWS NEAR 1.5 BY SAT
AFTERNOON...AND LIKELY RESULT IN BETTER COVERAGE/POTENTIAL FOR
SHRA/TSRA AS COMPARED TO TODAY...EVEN WITH BETTER FORCING IN PLACE
TODAY. ALMOST SOMEWHAT OF A TYPICAL SUMMER PATTERN...ALBEIT WITH
BETTER DYNAMICS/FLOW ALOFT THAN WOULD BE SEEN ON A TYPICAL SUMMER
PULSE THUNDERSTORM DAY. THUS...HAVE OPTED FOR HIGH CHC/LIKELY POPS
FOR SHRA/TSRA SAT AFTERNOON MUCH OF THE CWA...WITH THE BEST
CHANCES WEST OF THE BLUE RIDGE FURTHEST AWAY FROM THE UPPER
RIDGE.
QPF SHOULD NOT BE AN ISSUE THROUGH THE NEAR TERM...WITH AMOUNTS
NEAR 1/2 INCH WEST TO LESS THAN 1/4 INCH FAR SOUTHEAST. ANY
FLOODING ISSUES SHOULD BE CONFINED TO NEXT WEEK AFTER SEVERAL DAYS
OF SHRA/TSRA HAVE IMPACTED THE REGION...NOT WITH THIS FIRST ROUND.
TEMPS WILL REMAIN QUITE WARM TODAY...ESPECIALLY IN THE EAST. MIN
TEMPS TONIGHT SHOULD REMAIN VERY MILD...FROM THE UPPER 50S
WEST/WETTER AREAS TO THE MID 60S SOUTHEAST PARTS OF THE PIEDMONT.
EVEN MORE CLOUDS AND BETTER SHRA CHANCES SHOULD YIELD MAX TEMPS
SAT MOSTLY IN THE 70S...WITH 60S POSSIBLE IN THE MOUNTAINS.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
AS OF 345 AM EDT FRIDAY...
SHOWER AND THUNDERSTORM ACTIVITY WILL GRADUALLY DIMINISH SATURDAY
EVENING AS THE UPPER LEVEL DISTURBANCE TRIGGERING THE CONVECTION
EARLIER IN THE DAY PUSHES TOWARD THE COAST...ALLOWING WINDS TO SHIFT
NORTHWESTERLY AND DOWNSLOPE. OVERNIGHT TEMPERATURES WILL BE SLIGHTLY
COOLER COMPARED TO THE NIGHT BEFORE...BUT WILL STILL HOLD IN THE 50S
FOR MOST LOCATIONS.
UPPER LEVEL RIDGING WILL BECOME INCREASINGLY AMPLIFIED ALONG THE
ATLANTIC COAST SUNDAY AS A DEEP UPPER TROUGH DIGS ACROSS THE
INTERMOUNTAIN WEST. THE BUILDING RIDGE WILL CAUSE THE NORTHWESTERLY
WINDS TO RETURN SOUTHWESTERLY EARLY IN THE DAY..RESUMING THE FLOW OF
MOIST HUMID AIR INTO THE MID ATLANTIC. REGARDLESS...INSTABILITY WILL
BE MORE LIMITED ON SUNDAY COMPARED TO SATURDAY...AND WHILE A FEW
SHOWERS AND THUNDERSTORMS ARE EXPECTED...BELIEVE THEY WILL BE SPOTTY
AND DISORGANIZED IN NATURE...AND WILL DIMINISH QUICKLY TOWARD
SUNSET. OTHERWISE...PARTLY CLOUDY SKIES WILL ALLOW ENOUGH SUNSHINE
TO REACH THE SURFACE TO PUSH AFTERNOON TEMPERATURES INTO THE MID 80S
EAST OF THE BLUE RIDGE...WHILE UPPER 70S TO LOW 80S CAN BE EXPECTED
FOR THE MOUNTAINS. SUNDAY NIGHT WILL BE MILD AND SOMEWHAT
MUGGY...WITH PATCHY FOG LIKELY ACROSS THE REGION. LOWS WILL RANGE
FROM THE UPPER 50S TO THE LOW 60S FOR MOST LOCATIONS.
THE DEEP UPPER TROUGH AND ITS ASSOCIATED COLD FRONT WILL SHIFT EAST
ON MONDAY TO PASS OVER THE PLAINS. RIDGING WILL STILL MAINTAIN ITS
INFLUENCE ALONG THE APPALACHIAN CHAIN...BUT MAY SEE A LITTLE MORE
INSTABILITY AS AFTERNOON TEMPERATURES CLIMB TO THE LOW 80S WEST AND
THE UPPER 80S EAST. MODELS ARE NOT INDICATING ANY SIGNIFICANT
DISTURBANCES PASSING ACROSS THE AREA...AND BELIEVE ANY SHOWER AND
THUNDERSTORM ACTIVITY WILL AGAIN BE SPOTTY AND DISORGANIZED. EXPECT
OVERNIGHT LOWS IN THE UPPER 50S TO THE MID 60S...WITH MORE PATCHY
FOG POSSIBLE...ESPECIALLY IN AREAS THAT EXPERIENCE RAINFALL.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 145 PM EDT THURSDAY
WHILE LONG RANGE MODELS ARE STILL SHOWING SOME TIMING DIFFERENCES...
THE OVERALL TREND IS TO KEEP THE APPROACHING COLD FRONT MOVING
SLOWER INTO MIDWEEK. THIS WILL KEEP OUR AREA IN THE WARM SECTOR
LONGER...WITH INCREASED CHANCES OF SHOWERS AND STORMS TUESDAY AND
WEDNESDAY. WEDNESDAY STILL LOOKS TO BE THE WETTER OF THE TWO DAYS AS
FRONT REACHES THE CWA. MODELS/WPC SHOW FRONT EDGING EAST TO THE
PIEDMONT THURSDAY WITH BEST THREAT FOR CONVECTION IN THE PIEDMONT.
TEMPERATURES BY MIDWEEK SHOULD START TO LOWER BUT STILL LOOKING
HUMID UNTIL FRONT REACHES THE COAST BY THURSDAY NIGHT AND FRIDAY.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 140 PM EDT FRIDAY...
WILL EXPERIENCE VFR CONDITIONS THROUGH THE AFTERNOON INTO THE
EVENING. ISOLATED TO SCATTERED SHOWERS ALONG WITH A THUNDERSTORM
COULD IMPACT BCB/BLF/LWB THIS AFTERNOON INTO ROANOKE LATE
AFTERNOON. CONFIDENCE NOT HIGH ENOUGH FOR PREDOMINANT THUNDER...AS
INSTABILITY AND COVERAGE NOT ALL THAT HIGH.
ISSUE TONIGHT WILL BE THE COVERAGE OF RAIN SHOWERS AND EFFECT ON
CIGS AND VSBYS. ATTM...MODELS AND FORECAST SOUNDINGS SUGGEST
LIMITED THREAT OF SUB VFR CIGS/VSBYS THOUGH MOISTENING OF THE
AIRMASS MAY FAVOR SOME FOG IN THE VALLEYS AROUND BCB/LWB/DAN. WILL
LEAVE OUT FOR NOW. SHOULD BE A LULL IN PRECIP OVERNIGHT.
FRONT APPEARS TO BE STAYING NORTHWEST OF US INTO SATURDAY AS UPPER
LEVELS ENERGY SHEARS OUT TO THE NORTHEAST. WILL SEE SCATTERED
TO NUMEROUS COVERAGE ACROSS BY LATE SAT MORNING INTO THE AFTERNOON
MAINLY WEST OF THE BLUE RIDGE.
GUSTY SW WINDS THIS AFTERNOON TAPER OFF THIS EVENING THEN KICK UP
AGAIN LATE SAT MORNING...GENERALLY GUSTS AROUND 15-25 KNOTS.
LIKELIHOOD FOR SUB-VFR AT TIMES SATURDAY AFTERNOON WITH SHRA/TSRA
AHEAD OF THE FRONT MOVING SLOWLY EAST AND DEEPER MOISTURE IN
PLACE. BOUNDARY MAY WASH OUT UPON CROSSING THE AREA OR STALL JUST
OFF TO THE WEST BY SUNDAY WITH MAINLY VFR CONDITIONS EXPECTED
OUTSIDE OF OCNL MVFR IN MAINLY ISOLATED MOUNTAIN SHOWERS AS
LEFTOVER MOISTURE APPEARS QUITE SHALLOW. RIDGE OFFSHORE
STRENGTHENS AGAIN ON MONDAY AHEAD OF ANOTHER FRONT TO THE WEST
WITH MAINLY VFR EXCLUDING PERHAPS BRIEF MVFR IN A LATE DAY SHRA
ESPCLY MOUNTAINS. THIS COLD FRONT APPROACHES FROM THE WEST TUESDAY
WITH MOISTURE INCREASING AND CIGS LOWERING TOWARD MVFR LEVELS
ESPCLY LATER IN THE DAY WHEN A FEW BANDS OF SHOWERS APPEAR
POSSIBLE.
&&
.CLIMATE...
ANOTHER VERY WARM DAY ALREADY. CLOUDS AND SHOWERS MAY LIMIT TEMPS
FROM RISING MUCH MORE IN THE WEST BUT STILL POSSIBILITY EXISTS FOR
RECORD HIGHS AT BLF/BCB/LWB. HERE ARE THE RECORDS FOR MAY 9TH AND
CURRENT FORECAST HIGHS.
STATION CURRENT RECORD/YEAR FORECAST HIGH
ROA 92/1963 87
LYH 94/1936 88
DAN 94/1963 90
BCB 85/1966 84
BLF 84/2005 84
LWB 82/2000 83
&&
.EQUIPMENT...
BLACKSBURG RADAR NOW WORKING AS AC UNIT FIXED. MORE WORK ON THE
RADAR IS PLANNED MONDAY NEXT WEEK WEATHER PERMITTING.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...RAB/WP
NEAR TERM...RAB/WP
SHORT TERM...NF
LONG TERM...NF/WP
AVIATION...RAB/WP
CLIMATE...WP
EQUIPMENT...WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1245 PM EDT FRI MAY 9 2014
.SYNOPSIS...
HIGH PRESSURE NOW OVER THE SOUTHEAST COAST WILL PUMP MOISTURE UP
OUR WAY THIS AFTERNOON IN ADVANCE OF A FRONT. THIS SYSTEM HEADS
OUT BY SATURDAY NIGHT WITH ANOTHER UPPER HIGH MOVING IN FOR SUNDAY
AND MONDAY. A STRONG FRONT ARRIVES IN THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /THROUGH SATURDAY/...
AS OF 1220 PM EDT FRIDAY...
CU FIELD INCREASING OVER THE AREA...WITH SOME VERTICAL EXTENT TO
SOME. LATEST RUC MESOANLYSIS PER SPC PAGE SHOWING SBCAPES ABOVE
500 J/KG OVER THE SOUTHEAST BUT REMAINING LOWER IN THE MOUNTAINS.
HIGH-RES MODELS SHOW SHOWERS DEVELOPING ACROSS THE SRN BLUE RIDGE
INTO THE WV MTNS THROUGH MID AFTERNOON WITH BETTER COVERAGE OVER
THE MOUNTAINS AFTER 4-5 PM AS MID LEVEL VORT MOVES FROM TN TO THE
CENTRAL APPALACHIANS. WILL KEEP POPS IN THE CHANCE RANGE...HIGHER
IN THE FAR WEST. EXPECTING LESS THREAT IN THE EAST ALTHOUGH GIVEN
WARMER TEMPS...ISOLATED THUNDERSTORMS ARE POSSIBLE AFTER 4 PM.
RAISED HIGHS...MAINLY EAST OF THE BLUE RIDGE AS MORE SUNSHINE
OCCURRING AND TEMPS WERE ALREADY RUNNING ABOUT 3-6 DEGREES WARMER
THAN FORECAST AT NOON. SO LOOKING AT AROUND 90 SOUTHSIDE VA/NW NC
PIEDMONT. RECORDS ARE POSSIBLE MAINLY THE MOUNTAINS. SEE CLIMATE
SECTION BELOW. AS THE SHOWERS AND STORMS FORM...EXPECT TEMPS TO
COOL SOME.
PREVIOUS VALID DISCUSSION...
FOCUS THROUGH THE NEAR TERM WILL BE ON INCREASING CHANCES FOR
CONVECTION INTO SATURDAY ASSOCIATED WITH AN APPROACHING COLD
FRONT AND UPPER TROUGH. THE UPPER TROUGH...THE SAME ONE THAT HAS
ASSOCIATED WITH MORE WIDESPREAD SEVERE THUNDERSTORMS IN THE
MIDWEST/SOUTHERN PLAINS...WILL SHIFT NORTHEASTWARD TOWARD THE
GREAT LAKES AND WEAKEN/SHEAR OUT CONSIDERABLY AS IT APPROACHES THE
MID-ATLANTIC AND THE UPPER RIDGE IN PLACE ALONG THE EAST COAST.
THE BROOKS-CRAVEN SIGNIFICANT SVR PARAMETER...SUGGESTS THAT THE
THREAT FOR THUNDERSTORMS LATE THIS AFTERNOON/EVENING IS MARGINAL
AT BEST...WITH MOST VALUES 5000 OR LESS.
AS THE UPPER TROUGH MOVES ACROSS THE REGION OVERNIGHT/EARLY SAT
AND THE LOW-LEVEL AIR MASS CONTINUES TO MOISTEN...EXPECT SCATTERED
SHOWERS TO CONTINUE OVERNIGHT/EARLY SAT...ESPECIALLY WEST OF THE
BLUE RIDGE WHERE THE BEST FORCING WILL REMAIN. SATURDAY...THE
ENTIRE CWA REMAINS UNDER AN INCREASINGLY MOIST/MARGINALLY UNSTABLE
AIR MASS WITH CONSIDERABLE CONVECTIVE DEBRIS IN PLACE. THE MAIN
UPPER SUPPORT HAS PASSED BY TO THE NORTH...BUT BROAD WSW
FLOW/TROUGHING REMAINS IN PLACE ACROSS MUCH OF THE U.S. WEAK
SUBTLE IMPULSES EMBEDDED WITHIN THE UPPER FLOW WILL IMPINGE ON THE
MORE UNSTABLE/MOIST ATMOSPHERE...PWS NEAR 1.5 BY SAT
AFTERNOON...AND LIKELY RESULT IN BETTER COVERAGE/POTENTIAL FOR
SHRA/TSRA AS COMPARED TO TODAY...EVEN WITH BETTER FORCING IN PLACE
TODAY. ALMOST SOMEWHAT OF A TYPICAL SUMMER PATTERN...ALBEIT WITH
BETTER DYNAMICS/FLOW ALOFT THAN WOULD BE SEEN ON A TYPICAL SUMMER
PULSE THUNDERSTORM DAY. THUS...HAVE OPTED FOR HIGH CHC/LIKELY POPS
FOR SHRA/TSRA SAT AFTERNOON MUCH OF THE CWA...WITH THE BEST
CHANCES WEST OF THE BLUE RIDGE FURTHEST AWAY FROM THE UPPER
RIDGE.
QPF SHOULD NOT BE AN ISSUE THROUGH THE NEAR TERM...WITH AMOUNTS
NEAR 1/2 INCH WEST TO LESS THAN 1/4 INCH FAR SOUTHEAST. ANY
FLOODING ISSUES SHOULD BE CONFINED TO NEXT WEEK AFTER SEVERAL DAYS
OF SHRA/TSRA HAVE IMPACTED THE REGION...NOT WITH THIS FIRST ROUND.
TEMPS WILL REMAIN QUITE WARM TODAY...ESPECIALLY IN THE EAST. MIN
TEMPS TONIGHT SHOULD REMAIN VERY MILD...FROM THE UPPER 50S
WEST/WETTER AREAS TO THE MID 60S SOUTHEAST PARTS OF THE PIEDMONT.
EVEN MORE CLOUDS AND BETTER SHRA CHANCES SHOULD YIELD MAX TEMPS
SAT MOSTLY IN THE 70S...WITH 60S POSSIBLE IN THE MOUNTAINS.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
AS OF 345 AM EDT FRIDAY...
SHOWER AND THUNDERSTORM ACTIVITY WILL GRADUALLY DIMINISH SATURDAY
EVENING AS THE UPPER LEVEL DISTURBANCE TRIGGERING THE CONVECTION
EARLIER IN THE DAY PUSHES TOWARD THE COAST...ALLOWING WINDS TO SHIFT
NORTHWESTERLY AND DOWNSLOPE. OVERNIGHT TEMPERATURES WILL BE SLIGHTLY
COOLER COMPARED TO THE NIGHT BEFORE...BUT WILL STILL HOLD IN THE 50S
FOR MOST LOCATIONS.
UPPER LEVEL RIDGING WILL BECOME INCREASINGLY AMPLIFIED ALONG THE
ATLANTIC COAST SUNDAY AS A DEEP UPPER TROUGH DIGS ACROSS THE
INTERMOUNTAIN WEST. THE BUILDING RIDGE WILL CAUSE THE NORTHWESTERLY
WINDS TO RETURN SOUTHWESTERLY EARLY IN THE DAY..RESUMING THE FLOW OF
MOIST HUMID AIR INTO THE MID ATLANTIC. REGARDLESS...INSTABILITY WILL
BE MORE LIMITED ON SUNDAY COMPARED TO SATURDAY...AND WHILE A FEW
SHOWERS AND THUNDERSTORMS ARE EXPECTED...BELIEVE THEY WILL BE SPOTTY
AND DISORGANIZED IN NATURE...AND WILL DIMINISH QUICKLY TOWARD
SUNSET. OTHERWISE...PARTLY CLOUDY SKIES WILL ALLOW ENOUGH SUNSHINE
TO REACH THE SURFACE TO PUSH AFTERNOON TEMPERATURES INTO THE MID 80S
EAST OF THE BLUE RIDGE...WHILE UPPER 70S TO LOW 80S CAN BE EXPECTED
FOR THE MOUNTAINS. SUNDAY NIGHT WILL BE MILD AND SOMEWHAT
MUGGY...WITH PATCHY FOG LIKELY ACROSS THE REGION. LOWS WILL RANGE
FROM THE UPPER 50S TO THE LOW 60S FOR MOST LOCATIONS.
THE DEEP UPPER TROUGH AND ITS ASSOCIATED COLD FRONT WILL SHIFT EAST
ON MONDAY TO PASS OVER THE PLAINS. RIDGING WILL STILL MAINTAIN ITS
INFLUENCE ALONG THE APPALACHIAN CHAIN...BUT MAY SEE A LITTLE MORE
INSTABILITY AS AFTERNOON TEMPERATURES CLIMB TO THE LOW 80S WEST AND
THE UPPER 80S EAST. MODELS ARE NOT INDICATING ANY SIGNIFICANT
DISTURBANCES PASSING ACROSS THE AREA...AND BELIEVE ANY SHOWER AND
THUNDERSTORM ACTIVITY WILL AGAIN BE SPOTTY AND DISORGANIZED. EXPECT
OVERNIGHT LOWS IN THE UPPER 50S TO THE MID 60S...WITH MORE PATCHY
FOG POSSIBLE...ESPECIALLY IN AREAS THAT EXPERIENCE RAINFALL.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 145 PM EDT THURSDAY
WHILE LONG RANGE MODELS ARE STILL SHOWING SOME TIMING DIFFERENCES...
THE OVERALL TREND IS TO KEEP THE APPROACHING COLD FRONT MOVING
SLOWER INTO MIDWEEK. THIS WILL KEEP OUR AREA IN THE WARM SECTOR
LONGER...WITH INCREASED CHANCES OF SHOWERS AND STORMS TUESDAY AND
WEDNESDAY. WEDNESDAY STILL LOOKS TO BE THE WETTER OF THE TWO DAYS AS
FRONT REACHES THE CWA. MODELS/WPC SHOW FRONT EDGING EAST TO THE
PIEDMONT THURSDAY WITH BEST THREAT FOR CONVECTION IN THE PIEDMONT.
TEMPERATURES BY MIDWEEK SHOULD START TO LOWER BUT STILL LOOKING
HUMID UNTIL FRONT REACHES THE COAST BY THURSDAY NIGHT AND FRIDAY.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
AS OF 740 AM EDT FRIDAY...
VFR CIGS/VSBYS EXPECTED THROUGH THE TAF VALID PERIOD...DESPITE AN
APPROACHING WEATHER SYSTEM. HOWEVER...BKN-OVC HIGH-MID CLOUDS
WILL OVERSPREAD THE REGION THROUGHOUT THE DAY IN ADVANCE OF THE
CENTRAL U.S. UPPER TROUGH. SW SFC WINDS WILL BEGIN TO BRING GULF
MOISTURE INTO THE REGION BY MID DAY/EARLY AFTERNOON...WHICH SHOULD
BE REALIZED IN SCT HIGH BASED 050-060 CU...ESPECIALLY WEST OF THE
BLUE RIDGE AND MOST NOTABLY IN EASTERN WV. DRY SFC AIR WILL BE
SLOW TO MODIFY...SO NOT EXPECTING ANY CIGS BELOW 045 THROUGH 12Z
SAT...BUT WILL NEED TO WATCH EASTERN WV AREAS AS -SHRA LATE
TODAY/TONIGHT COULD POTENTIALLY RESULT IN LOWER CIGS...POSSIBLY
MVFR. MODELS SLIGHTLY FASTER ON ARRIVAL OF FRONTAL PCPN IN THE
WESTERN PARTS OF THE CWA LATE THIS AFTERNOON/EVENING...SO HAVE
INTRODUCED VCSH/-SHRA 20Z BLF/LWB TO AROUND 00Z ROA. PCPN WILL
LIKELY HAVE A HARD TIME SPREADING EAST OF THE BLUE RIDGE AS UPPER
SUPPORT WANES AND SHIFTS NORTH OF THE REGION IN SHEARING UPPER
TROUGH. THUS...HAVE NOT INTRODUCED PCPN YET FOR DAN AND ONLY
TEMPO P6SM -RA FOR LYH. INTRODUCED SOME MVFR IN -SHRA BR
BLF/LWB...BUT CONFIDENCE IN THIS IS LOW UNTIL LOWER LEVELS OF THE
ATMOSPHERE SATURATE. SHOULD SEE BETTER CHANCE FOR SHRA/TSRA ALL
AREAS...INCLUDING DAN/LYH/ROA SAT AFT 16Z. WINDS...LIGHT SW OR
CALM THROUGH 14Z...THEN SW ALL SITES AFT 14Z 8-12KTS WITH GUSTS TO
20-22KTS BLF/BCB/ROA/DAN FROM LATE MORNING THROUGH LATE AFTERNOON.
WINDS WILL DIMINISH TO 7KTS OR LESS AFT 00Z.
HIGH CONFIDENCE IN VFR CIGS/VSBYS THROUGH 20Z...THEN MEDIUM
CONFIDENCE IN CIGS/VSBYS...ESPECIALLY WEST OF THE BLUE RIDGE.
HIGH CONFIDENCE IN WIND DIR...MEDIUM TO HIGH CONFIDENCE IN WIND
SPD THROUGH THE TAF VALID PERIOD.
LOW CONFIDENCE IN ANY THUNDERSTORM POTENTIAL BLF/LWB/BCB LATE IN
THE DAY OR EARLY EVENING.
EXTENDED AVIATION DISCUSSION...
CONTINUED LIKELIHOOD FOR SUB-VFR AT TIMES SATURDAY WITH SHRA/TSRA
AHEAD OF THE FRONT MOVING SLOWLY EAST AND DEEPER MOISTURE IN
PLACE. BOUNDARY MAY WASH OUT UPON CROSSING THE AREA OR STALL JUST
OFF TO THE WEST BY SUNDAY WITH MAINLY VFR CONDITIONS EXPECTED
OUTSIDE OF OCNL MVFR IN MAINLY ISOLATED MOUNTAIN SHOWERS AS
LEFTOVER MOISTURE APPEARS QUITE SHALLOW. RIDGE OFFSHORE
STRENGTHENS AGAIN ON MONDAY AHEAD OF ANOTHER FRONT TO THE WEST
WITH MAINLY VFR EXCLUDING PERHAPS BRIEF MVFR IN A LATE DAY SHRA
ESPCLY MOUNTAINS. THIS COLD FRONT APPROACHES FROM THE WEST TUESDAY
WITH MOISTURE INCREASING AND CIGS LOWERING TOWARD MVFR LEVELS
ESPCLY LATER IN THE DAY WHEN A FEW BANDS OF SHOWERS APPEAR
POSSIBLE.
&&
.CLIMATE...
ANOTHER VERY WARM DAY ALREADY. CLOUDS AND SHOWERS MAY LIMIT TEMPS
FROM RISING MUCH MORE IN THE WEST BUT STILL POSSIBILITY EXISTS FOR
RECORD HIGHS AT BLF/BCB/LWB. HERE ARE THE RECORDS FOR MAY 9TH AND
CURRENT FORECAST HIGHS.
STATION CURRENT RECORD/YEAR FORECAST HIGH
ROA 92/1963 87
LYH 94/1936 88
DAN 94/1963 90
BCB 85/1966 84
BLF 84/2005 84
LWB 82/2000 83
&&
.EQUIPMENT...
BLACKSBURG RADAR NOW WORKING AS AC UNIT FIXED. MORE WORK ON THE
RADAR IS PLANNED MONDAY NEXT WEEK WEATHER PERMITTING.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...RAB/WP
NEAR TERM...RAB/WP
SHORT TERM...NF
LONG TERM...NF/WP
AVIATION...JH/RAB
CLIMATE...WP
EQUIPMENT...WP
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1058 PM CDT SAT MAY 10 2014
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND SUNDAY
ISSUED AT 324 PM CDT SAT MAY 10 2014
CONCERN ON PCPN CHANCES TONIGHT INTO SUNDAY.
HIGH PRESSURE OVER STATE...LEADING TO DEEP MIXING AND DEW POINTS
IN THE LOWER 20S IN SOME OF OUR DRIER SPOTS. MORNING SOUNDINGS MSP
AND GRB SHOWING THIS DRY AIR. AREA OF CLOUDS/SHOWERS WITH SHORT
WAVE HAVING HARD TIME MOVING NORTH. HRRR SHOWS THE AREA DRYING UP
AS MOVES INTO SOUTHWEST WI. HAVE BACKED OFF ON CLOUDS/POPS THROUGH EARLY
EVENING HOURS.
SHORT WAVE TO WEAKEN AS IT LIFTS NORTH TO THE WEST OF STATE.
MODELS TRENDS HAVE BEEN WEST WITH PCPN WITH LOW LEVEL FLOW FOCUSED
INTO SOUTHERN MN...SHIFTING SOUTHWEST INTO WESTERN WI LATE. HAVE
BACKED OFF ON EASTWARD PROGRESSION WITH POPS...THINKING BEST POPS
NORTH LATE TONIGHT WITH 850 FRONT LIFTING INTO THE AREA.
PCPN WITH THE LEAD WAVE EXPECTED TO EXIT THE N DURING THE MORNING...THEN
EXPECT A LULL FOR THE MUCH OF THE DAY. MADE LITTLE CHANGE TO
PREVIOUS FORECAST FOR TEMPS/AFTN POPS.
.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY
ISSUED AT 324 PM CDT SAT MAY 10 2014
MAIN CONCERN WILL BE THE SYSTEM SUNDAY NIGHT INTO TUESDAY MORNING.
LOW LEVEL JET IS EXPECTED TO INCREASE TO 50 TO 60 KTS SUNDAY NIGHT.
MID LEVEL LAPSE RATES WERE NEAR 6 C/KM. THERE IS CONSIDERABLE CONCERN
WHERE AXIS OF HEAVY RAIN WILL SET UP. BASED ON POSITION OF THE
SURFACE WARM FRONT...WRF MODEL TOO FAR NORTH WHILE THE GFS IS FURTHER
SOUTH COMPARED TO THE CANADIAN/ECMWF. IF GFS IS CORRECT...THE
HEAVY RAIN SUNDAY NIGHT WOULD BE SOUTH OF OUR AREA AND THE WARM
FRONT WILL BE NO WHERE CLOSE TO OUR FORECAST AREA AS OUTFLOW
BOUNDARIES SHOULD SHOVE THE FRONT SOUTH. IF THE ECMWF/CANADIAN
ARE CORRECT...OUR SOUTHERN FORECAST AREA WILL BE ON THE NORTHERN
EDGE OF THE HEAVY RAIN. MAIN CONCERN FOR LATER SUNDAY NIGHT WILL
BE THE POTENTIAL FOR HEAVY RAIN AND SMALL HAIL.
EITHER WAY...SURFACE WARM FRONT WILL BE SOUTH OF OUR AREA ON
MONDAY. ONGOING CONVECTION/OUTFLOW BOUNDARIES FROM OVERNIGHT
CONVECTION THAT LINGERS INTO MONDAY MORNING WILL SLOW THE NORTHWARD
PROGRESS OF THE WARM FRONT. THE SEVERE POTENTIAL REMAINS UNCERTAIN
FOR THESE REASONS. IF WE DO GET SOME CLEARING ACROSS THE SOUTH
ON MONDAY...SOME OF THE STORMS COULD BECOME STRONG OR SEVERE...
ESPECIALLY SOUTH OF HIGHWAY 29. A SECONDARY WAVE IS EXPECTED TO
MOVE ALONG THE FRONT MONDAY NIGHT INTO TUESDAY MORNING...BRINGING
MORE LOCALLY HEAVY RAIN. RAINFALL TOTALS OF 1 TO 2 INCHES ARE
EXPECTED ACROSS MUCH OF THE AREA...WITH LOCALLY HIGHER AMOUNTS
ACROSS THE SOUTH.
HIGH PRESSURE BUILDS INTO THE REGION TUESDAY NIGHT. COOL CYCLONIC
FLOW EXPECTED FOR THE REMAINDER OF THE WORK WEEK...BRINGING A
CHANCE FOR INSTABILITY SHOWERS WEDNESDAY THROUGH FRIDAY. THE
GREATEST CONCENTRATION OF SHOWERS WILL BE DURING THE AFTERNOON
AND EARLY EVENING HOURS. CAN NOT RULE OUT ISOLATED/SCATTERED
SHOWERS OUTSIDE THIS PERIOD EACH DAY DUE TO WEAK DISTURBANCES
MOVING WITH THE MEAN FLOW.
&&
.AVIATION...FOR 06Z TAF ISSUANCE
ISSUED AT 1058 PM CDT SAT MAY 10 2014
AFTER THE FIRST BATCH OF RAIN FIZZLED AS IT RAN INTO DRY
AIR...ANOTHER BAND OF RAIN IS GOING TO TRY TO PROCEED TO THE
NORTHEAST OVERNIGHT. IT TOO LOOKS TO BE STRUGGLING TO HOLD
TOGETHER...BUT DID THROW IN A TEMPO GROUP FOR LIGHT RAIN AT RHI
WHERE THE SREF HAS THE HIGHEST CHANCE OF PRECIP OVERNIGHT. STILL
SEE NOTHING TO SUPPORT GOING LOWER THAN VFR THOUGH. SOME SPOTTY
LIGHT RAIN SHOWERS MAY POP OVER THE COURSE OF THE MORNING THOUGH
CONFIDENCE IS NOT HIGH ENOUGH TO INCLUDE IN THE TAFS. A MUCH BETTER
CHANCE OF RAIN WILL ARRIVE SUNDAY EVENING WHEN A WARM FRONT LIFTS
INTO THE REGION. ANTICIPATE RAIN ARRIVING AND CIGS/VSBYS LOWERING
THROUGH THE EVENING HOURS.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....TE
LONG TERM......ECKBERG
AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
834 PM CDT SAT MAY 10 2014
.UPDATE...
ISSUED AT 834 PM CDT SAT MAY 10 2014
MAIN BAND OF RAIN IS ENTERING EASTERN MINNESOTA AND IOWA ALONG THE
LEAD MID LEVEL SHORT WAVE TROUGH THAT RUNS FROM SOUTHEAST NORTH
DAKOTA THROUGH SOUTHWEST MINNESOTA. THE 11.00Z RAP CONTINUES TO
SHOW A WEAKENING TREND IN INSTABILITY...BUT STILL HAS SOME FEEDING
INTO THE BACK EDGE OF THE SHORT WAVE TO WARRANT KEEPING A MENTION
OF THUNDER IN THROUGH THIS EVENING. HAVE SPED UP THE END TIME OF
THIS RAIN BASED ON CURRENT EXTRAPOLATION AND THE PAST FEW RUNS OF
THE HRRR WHICH HAS HAD A GOOD HANDLE ON THIS CONVECTION. WHILE
0-6KM WIND SHEAR IS DECENT...IT IS ALL IN THE LOW LEVELS AND NOT
IN THE LAYER WHERE THIS VERY SKINNY/WEAK INSTABILITY IS IN THE MID
LEVELS. THUS...AM NOT EXPECTING ANYTHING SEVERE THIS EVENING.
HAVE NOT MADE ANY CHANGES TO THE FORECAST FOR TOMORROW...BUT AS
PREVIOUSLY MENTIONED...IT WILL ALL DEPEND ON HOW FAR NORTH THE
WARM FRONT MAKES IT. ONE THING APPEARS CERTAIN AND THAT IS THE
INCREASE IN LOW LEVEL MOISTURE TRANSPORT THROUGH THE DAY AND INTO
THE NIGHT WHICH MAY LEAD TO SOME FLOODING ISSUES IF STORMS TRAIN
TO THE NORTH OF THE FRONT. WILL HAVE TO SEE HOW THE 11.00Z MODELS
COME UP BEFORE MAKING ANY WHOLESALE CHANGES TO THE FORECAST.
&&
.SHORT TERM...(TONIGHT THROUGH SUNDAY NIGHT)
ISSUED AT 310 PM CDT SAT MAY 10 2014
MAIN FORECAST CONCERNS THIS PERIOD...SHRA/TSRA CHANCES THIS EVENING
AND AGAIN SUN AFTERNOON/NIGHT. POTENTIAL HEAVY RAINS SUN NIGHT.
18Z DATA ANALYSIS HAD A WEAK RIDGE OF HIGH PRESSURE FROM NORTHEAST
MN THRU SOUTHEAST WI. SUNNY...QUIET DAY OVER THE NORTHEAST HALF OF
THE REGION. WV IMAGERY SHOWED A MORE ROBUST LOOKING SHORTWAVE
LIFTING NORTHEAST ACROSS SD/NEB EARLY THIS AFTERNOON. THIS WAVE AND
SOME 850-700MB MOISTURE TRANSPORT/THERMO-DYNAMIC FORCING RESPONSIBLE
FOR A BROAD BAND OF SCT SHRA/ISOLATED TSRA LIFTING ACROSS NORTHERN
IA/SOUTHWEST MN. PER 10.12Z KMPX SOUNDING...PLENTY OF DRY AIR ABOVE
850MB AHEAD OF THIS BAND OF SHRA/TSRA TO OVERCOME BEFORE PRECIP
REACHES THE GROUND...AND MOST RAIN AMOUNTS SO FAR TODAY HAVE BEEN A
TRACE TO A FEW HUNDREDTHS OF AN INCH.
10.12Z MODELS INITIALIZED WELL...BUT FOR GFS ABOUT 5F HIGH ON SFC
DEW POINTS ACROSS THE SOUTH HALF OF THE UPPER MS VALLEY.
SOLUTIONS CONTINUE TO OFFER A TIGHTER CONSENSUS ON THE SHORTWAVE
TO LIFT ACROSS THE UPPER MIDWEST TONIGHT AND THE NEXT STRONG
TROUGHING/ ENERGY TO CROSS THE ROCKIES SUN/SUN NIGHT.
SLOWER/STRONGER ECMWF/ CAN-GEM OFFERING THE BETTER RUN-TO-RUN
CONSISTENCY WITH THE ROCKIES TROUGHING LATE SUN/SUN NIGHT WITH
GFS/NAM SLOWING TO MATCH UP. NAM APPEARS AS BIT OF AN OUTLIER AT
12Z MON WITH A FURTHER NORTH/EAST SFC LOW/TRAILING COLD FRONT AND
ITS SOLUTION GENERALLY DISCOUNTED. GIVEN THE NOW RATHER TIGHT NON-
NAM CONSENSUS THRU 12Z MON...SHORT- TERM FCST CONFIDENCE FOR A
RATHER ACTIVE PERIOD IS GOOD THIS CYCLE.
FIRST SHORTWAVE CROSSING THE UPPER MIDWEST TONIGHT WEAKENS AS
LOOSES THE BATTLE WITH THE RISING HGTS/RIDGING AHEAD OF THE
STRONGER TROUGHING DIGGING INTO THE ROCKIES. 925-700MB MOISTURE
TRANSPORT/ WARM ADVECTION AND SOME 295-305K ISENTROPIC LIFT STILL
SPREADS NORTHEAST ACROSS THE FCST AREA MAINLY LATE THIS
AFTERNOON/EVENING... WITH STEEPER MID LEVEL LAPSE RATES AND WEAK
INSTABILITY. WILL CONTINUE SHRA/TSRA CHANCES THRU THE EVENING...IN
THE 20-50 PERCENT RANGE...THEN TAPER/END THEM AFTER MIDNIGHT AS
THE LOWER LEVEL FORCING WEAKENS/MOVES EAST OF THE FCST AREA. MOST
RAIN AMOUNTS TONIGHT TO BE QUITE LIGHT.
BREAK FROM THE RAIN CHANCES LATE TONIGHT/SUN MORNING AS SOME 850-
700MB DRYING TEMPORARILY SPREADS ACROSS THE AREA. MOISTURE RETURN
AHEAD OF THE CENTRAL PLAINS LEE LOW ALREADY SPREAD ACROSS THE AREA
SUN MORNING...WITH THE 700MB MOISTURE ARRIVING DURING THE LATER
MORNING/EARLY AFTERNOON HOURS AND 925-50MB MOISTURE ARRIVING DURING
THE AFTERNOON. PW VALUES OF AROUND 1.5 INCHES TO SPREAD NORTH ACROSS
THE AREA FOR SUN AFTERNOON/NIGHT. QUESTION NO LONGER SEEMS IF ITS
GOING TO RAIN LATE SUN AFTERNOON/NIGHT BUT HOW MUCH. BROAD/DEEP
LAYERED FORCING/LIFT AHEAD OF THE SFC THRU MID LEVEL TROUGH SPREADS
ACROSS WITH THE MOISTURE INCREASE SUN AFTERNOON/NIGHT.
AT 00Z MON...MODEL SOUNDINGS SHOWING STABILITY/CIN OF 50-150IN THE
SFC-700MB LAYER WITH MUCAPES OF 500-1500 J/KG OVER MAINLY THE SOUTH
1/3 OF THE FCST AREA. LFC AROUND 700MB IN THE SOUNDINGS WITH THE CIN
IN A RATHER DEEP 900-700MB LAYER. CAPE PROFILE IS DEEP...BUT SKINNY.
WITH WARM CLOUD DEPTH OF AROUND 3500 METERS...THE SKINNY CAPE OF 500-
1500 J/KG DOES NOT SEEM LIKE ENOUGH FOR A BIG HAIL THREAT. WITH THE
AREA LOOKING TO BE NORTH OF THE WARM FRONT SUN EVENING AND THE CIN
BELOW 700MB...APPEARS MAIN TORNADO AND STRONG WIND THREAT WOULD
BE SOUTH OF THE FCST AREA. ALSO...NUMEROUS SHRA/TSRA EXPECTED TO
BE SPREADING INTO/ACROSS THE AREA SUN AFTERNOON/ EVENING...ALL
COMPETING FOR THE SAME CAPE/SHEAR...WILL REDUCE THE SEVERE THREAT
FROM ANY ONE TSRA. CONCERNS AS WELL ON SUN WITH HIGH TEMPS BEING
TOO WARM AND CAPE ON THE HIGH SIDE GIVEN THICKENING
CLOUDS/SHRA/TSRA SPREADING NORTH INTO THE AREA DURING THE
AFTERNOON.
THE 3500 METER WARM CLOUD DEPTH...A WARM FRONT TO THE SOUTH FOR
LIFTING...PW VALUES NEAR 200 PERCENT OF NORMAL AND A FEED OF THIS
MOISTURE ON A 40-50KT 850MB JET SUN NIGHT ALL POINT TSRA BEING
EFFICIENT RAIN MAKERS AND A HEAVY RAIN THREAT. CONSIDERED A FLOOD
WATCH FOR SUN NIGHT/MON...BUT IT WOULD HAVE AND TO BE RATHER BROAD
WITH QPF DETAIL DIFFERENCES AMONG THE MODELS. WILL ISSUE AND ESF FOR
NOW AND PASS ALONG CONCERNS TO THE MIDNIGHT CREW.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 310 PM CDT SAT MAY 10 2014
MAIN FORECAST CONCERNS MON THRU TUE NIGHT...SHRA/TSRA CHANCES/RAIN
AMOUNTS MON INTO MON NIGHT...COOLING TEMPERATURES.
MODEL RUNS OF 10.12Z OFFERING A TIGHTER CONSENSUS MON/MON NIGHT AS
THE MID LEVEL TROUGH LIFTS INTO THE UPPER MIDWEST AND THE SFC LOW
LIFTS TO LK SUPERIOR. TREND IS TOWARD COMPROMISE OF THE EARLIER RUNS
ON STRENGTH/TIMING OF THE MID LEVEL TROUGH INTO THE REGION WITH
SOMEWHAT BETTER RUN-TO-RUN CONSISTENCY BY THE ECMWF. IMPROVING
CONSENSUS TUE/TUE NIGHT AS THE TROUGH VIRTUALLY STALLS OVER THE
CENTRAL CONUS. FCST CONFIDENCE IN THE MON-TUE NIGHT PERIOD IS
AVERAGE TO GOOD THIS CYCLE.
BROAD/DEEP FORCING/LIFT CONTINUES OVER THE AREA MON...ALONG WITH A
FEED OF THE 1.5 INCH PW VALUES ON A 30-40KT 850MB JET. STRONGEST OF
THIS IS OVER THE FCST AREA IN THE MORNING...GRADUALLY TRANSLATING
EAST MON AFTERNOON/EVENING AS THE SFC THRU 850MB COLD FRONT/TROUGH
MOVE EAST INTO/ACROSS THE AREA. PLENTY OF FORCING/LIFT REMAINS OVER
THE WEST SIDE OF THE FCST AREA MON AFTERNOON/EVENING...WITH THE 700-
500MB TROUGH AXIS STILL WEST OF THE AREA AND SHORTWAVES LIFT UP THE
EAST SIDE OF THE TROUGH THRU WESTERN MN. HEAVIEST RAIN THREAT SHIFTS
EAST OF THE AREA THRU MON AFTERNOON/EVENING...BUT SHRA/TSRA LOOK TO
CONTINUE ACROSS THE ENTIRE FCST AREA MON AFTERNOON. AFTER A POSSIBLE
1 TO 2 INCHES OF RAIN SUN NIGHT...ANOTHER 1/4 TO 3/4 INCH OF RAIN
POSSIBLE MONDAY. SHRA/TSRA THEN TAPER OFF AND EXIT EAST THRU MON
NIGHT/TUE MORNING AS THE SFC-850MB TROUGH/FRONT MOVE EAST OF THE
AREA.
CONCERNS WITH THE SEVERE THREAT DEPICTED IN DAY 3 SIMILAR TO THOSE
CENTERED ON SUN EVENING. SHRA/TSRA SHOULD BE ONGOING ACROSS MUCH OF
THE UPPER MIDWEST MON MORNING...AND CONTINUE MUCH OF THE DAY. DEBRIS
CLOUDS AND THE RAIN SHOULD LIMIT HIGH TEMPS AND POTENTIAL FOR CAPE
TO BUILD ACROSS THE AREA. USED THE MODEL/ENSEMBLE CONSENSUS HIGHS
FOR MON BUT IF CLOUDS/SHRA/TSRA PREVAIL...THESE ARE LIKELY TOO WARM
RESULTING IN TOO MUCH CAPE IN THE PROGS. MON CAPE PROFILES ALSO DEEP
AND SKINNY SIMILAR TO SUN EVENING. NUMEROUS SHRA/TSRA ALL COMPETING
FOR THE SAME CAPE/SHEAR WILL AGAIN LIMIT THE SEVERE POTENTIAL WITH
ANY ONE STORM.
DRIER/COOLER 925-700MB AIR WRAPS ACROSS THE AREA FOR TUE AFTERNOON/
NIGHT FOR WHAT SHOULD BE DRY PERIODS AND A DECREASE OF CLOUDS. 850MB
TEMPS IN THE +2C TO -1C RANGE BY 12Z WED. THIS PLUS LIGHT WINDS AND
MOSTLY CLEAR SKIES TUE NIGHT...LOWS IN THE UPPER 30S-LOW 40S WED
MORNING APPEAR REASONABLE.
FOR WEDNESDAY THRU SATURDAY.../DAYS 4 TO 7/...
MAIN FORECAST CONCERNS THIS PERIOD...COOL TEMPERATURES AND -SHRA
CHANCES THRU THE PERIOD.
MEDIUM RANGE MODEL RUNS OF 10.00Z/10.12Z HAVE COME INTO BETTER
AGREEMENT WED/THU ON LOCATION/STRENGTH OF THE TROUGHING TO SLOWLY
MOVE ACROSS CENTRAL NOAM. MODELS CONVERGING TOWARD THE EARLIER
ECMWF RUNS. IMPROVING CONSENSUS FOR SOME NORTHERN STREAM ENERGY TO
DROP INTO THE UPPER MIDWEST THU/FRI...FURTHER DEEPENING THE TROUGH
AND CARVING OUT A MID LEVEL OVER THE WESTERN GREAT LAKES FOR FRI
INTO SAT. GIVEN THE IMPROVED MEDIUM RANGE MODEL CONSENSUS...DAY
4-7 FCST CONFIDENCE IS GENERALLY GOOD THIS CYCLE...ESPECIALLY FOR
BELOW NORMAL TEMPERATURES.
ONE SURGE OF COLDER LOW LEVEL HAS ALREADY SETTLED OVER THE REGION BY
WED. A SECONDARY...EVEN COLDER SURGE IS POISED TO DROP SOUTH INTO
THE REGION FOR THU/FRI. 850MB TEMPS PROGGED TO BOTTOM OUT IN THE
-1C TO -3C RANGE AT 12Z FRI. SOME TEMP RECOVERY SAT AS WARMER AIR
ACTUALLY WRAPS IN FROM THE NORTH. SIGNAL REMAINS CONSISTENT FOR
850MB TEMPS TO BE SOME 1.5 TO 2 STANDARD DEVIATIONS BELOW NORMAL
ACROSS THE UPPER MIDWEST FOR MOST OF THE WE-SAT PERIOD. CONFIDENCE
IS GOOD FOR DAY 4-7 HIGHS TO BE SOME 10-15F BELOW NORMAL. LOWS
THRU THE PERIOD A LITTLE TRICKER AND DEPENDENT ON EXTENT OF CLOUD
COVER ANY ONE NIGHT. WITH MODEST 925-700MB MOISTURE AND THE DEEP
COLD CORE TROUGH/LOW AND CYCLONIC FLOW OVER THE REGION...CLOUDS
EXPECTED TO PREVAIL MUCH OF THE WED-SAT PERIOD. IF ANY ONE OF THE
NIGHTS ENDS UP MORE CLEAR THAN CLOUDY...PATCHY FROST WOULD BE
EXPECTED...ESPECIALLY ALONG/NORTHEAST OF I-94 THU/FRI NIGHTS. FOR
NOW THE MODEL/ENSEMBLE CONSENSUS HIGHS/LOWS FOR WED- SAT ARE WELL
TRENDED.
LESS CONFIDENCE ON -SHRA CHANCES IN THE WED-SAT PERIOD AS THESE
CHANCES WILL DEPEND ON THE TIMING OF STRONGER SHORTWAVES THRU THE
PERSISTENT TROUGHING OVER THE REGION. PRESENT TIMING HAS ONE
STRONGER SHORTWAVE DROPPING INTO THE REGION WED THEN MORE
SHORTWAVE ENERGY ROTATING AROUND THE DEEP TROUGH/MID LEVEL LOW
OVER THE WESTERN GREAT LAKES FRI/SAT. WITH THE DEEP CYCLONIC
FLOW...COLD CORE OF 850-700MB TEMPS OVER THE REGION...STEEP SFC-
700MB LAPSE...RATES/WEAK INSTABILITY DURING THE AFTERNOON
HOURS...ANY SHORTWAVE WOULD BE CAPABLE OF TRIGGERING SCT -SHRA.
SMALL -SHRA CHANCES MUCH OF THE WED-SAT PERIOD STILL LOOK
REASONABLE UNTIL THE SHORTWAVE TIMING DETAILS CAN BE SORTED OUT.
ANY PRECIP DURING THE WED-SAT WOULD BE SCT AND LIGHT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 632 PM CDT SAT MAY 10 2014
THE MAIN FOCUS AT THE TAF SITES IS WITH THE NEXT ROUND OF RAIN AND
POSSIBLE THUNDERSTORMS THAT WILL MOVE THROUGH THIS EVENING.
CONDITIONS ARE VFR THROUGHOUT THE REGION...THOUGH SOME BRIEF DROPS
TO MVFR ARE POSSIBLE IF ANY THUNDERSTORMS DO MANAGE TO MAKE IT
INTO RST OR LSE. CONDITIONS APPEAR TO BECOME LESS FAVORABLE AS THE
NIGHT GOES ON...SO HAVE ONLY INCLUDED VCTS IN THE CURRENT TAFS AS
CONFIDENCE IS NOT VERY HIGH THAT ANY STORMS WILL MAKE IT INTO RST
OR LSE. ANOTHER ROUND OF STORMS WILL MOVE IN TOMORROW...BUT THAT
WILL LIKELY NOT BE UNTIL THE EVENING HOURS. CONDITIONS SHOULD
REMAIN VFR BETWEEN THESE ROUNDS OF SHOWERS/STORMS.
&&
.HYDROLOGY...
ISSUED AT 310 PM CDT SAT MAY 10 2014
MINOR FLOODING/HIGH WATER CONTINUES ALONG PORTIONS OF THE
MISSISSIPPI RIVER. LATER SUN AFTERNOON INTO MON EVENING WILL BE A
WET PERIOD...WITH POTENTIAL FOR 1 TO 2 OR MORE INCHES OF RAINFALL
DURING THAT PERIOD. THE HEAVIEST RAIN/HIGHEST TOTALS WILL FALL
SUNDAY NIGHT INTO MONDAY MORNING. THESE RAINS COULD HAVE
ADDITIONAL IMPACTS ON BOTH TRIBUTARIES AND THE MISSISSIPPI
RIVER...SLOWING THE RATES OF FALL...PRODUCE ADDITIONAL RISES OR
RENEWED FLOODING. WILL ISSUE AN ESF CONCERNING THE POTENTIAL
HEAVY RAINS SUN NIGHT/MON AND RISING RIVER LEVELS/FLOODING THREAT.
CHECK THE LATEST HYDROLOGIC STATEMENTS FOR THE DETAILS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...HALBACH
SHORT TERM...RRS
LONG TERM....RRS
AVIATION...HALBACH
HYDROLOGY....RRS
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
606 PM CDT SAT MAY 10 2014
UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND SUNDAY
ISSUED AT 324 PM CDT SAT MAY 10 2014
CONCERN ON PCPN CHANCES TONIGHT INTO SUNDAY.
HIGH PRESSURE OVER STATE...LEADING TO DEEP MIXING AND DEW POINTS
IN THE LOWER 20S IN SOME OF OUR DRIER SPOTS. MORNING SOUNDINGS MSP
AND GRB SHOWING THIS DRY AIR. AREA OF CLOUDS/SHOWERS WITH SHORT
WAVE HAVING HARD TIME MOVING NORTH. HRRR SHOWS THE AREA DRYING UP
AS MOVES INTO SOUTHWEST WI. HAVE BACKED OFF ON CLOUDS/POPS THROUGH EARLY
EVENING HOURS.
SHORT WAVE TO WEAKEN AS IT LIFTS NORTH TO THE WEST OF STATE.
MODELS TRENDS HAVE BEEN WEST WITH PCPN WITH LOW LEVEL FLOW FOCUSED
INTO SOUTHERN MN...SHIFTING SOUTHWEST INTO WESTERN WI LATE. HAVE
BACKED OFF ON EASTWARD PROGRESSION WITH POPS...THINKING BEST POPS
NORTH LATE TONIGHT WITH 850 FRONT LIFTING INTO THE AREA.
PCPN WITH THE LEAD WAVE EXPECTED TO EXIT THE N DURING THE MORNING...THEN
EXPECT A LULL FOR THE MUCH OF THE DAY. MADE LITTLE CHANGE TO
PREVIOUS FORECAST FOR TEMPS/AFTN POPS.
.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY
ISSUED AT 324 PM CDT SAT MAY 10 2014
MAIN CONCERN WILL BE THE SYSTEM SUNDAY NIGHT INTO TUESDAY MORNING.
LOW LEVEL JET IS EXPECTED TO INCREASE TO 50 TO 60 KTS SUNDAY NIGHT.
MID LEVEL LAPSE RATES WERE NEAR 6 C/KM. THERE IS CONSIDERABLE CONCERN
WHERE AXIS OF HEAVY RAIN WILL SET UP. BASED ON POSITION OF THE
SURFACE WARM FRONT...WRF MODEL TOO FAR NORTH WHILE THE GFS IS FURTHER
SOUTH COMPARED TO THE CANADIAN/ECMWF. IF GFS IS CORRECT...THE
HEAVY RAIN SUNDAY NIGHT WOULD BE SOUTH OF OUR AREA AND THE WARM
FRONT WILL BE NO WHERE CLOSE TO OUR FORECAST AREA AS OUTFLOW
BOUNDARIES SHOULD SHOVE THE FRONT SOUTH. IF THE ECMWF/CANADIAN
ARE CORRECT...OUR SOUTHERN FORECAST AREA WILL BE ON THE NORTHERN
EDGE OF THE HEAVY RAIN. MAIN CONCERN FOR LATER SUNDAY NIGHT WILL
BE THE POTENTIAL FOR HEAVY RAIN AND SMALL HAIL.
EITHER WAY...SURFACE WARM FRONT WILL BE SOUTH OF OUR AREA ON
MONDAY. ONGOING CONVECTION/OUTFLOW BOUNDARIES FROM OVERNIGHT
CONVECTION THAT LINGERS INTO MONDAY MORNING WILL SLOW THE NORTHWARD
PROGRESS OF THE WARM FRONT. THE SEVERE POTENTIAL REMAINS UNCERTAIN
FOR THESE REASONS. IF WE DO GET SOME CLEARING ACROSS THE SOUTH
ON MONDAY...SOME OF THE STORMS COULD BECOME STRONG OR SEVERE...
ESPECIALLY SOUTH OF HIGHWAY 29. A SECONDARY WAVE IS EXPECTED TO
MOVE ALONG THE FRONT MONDAY NIGHT INTO TUESDAY MORNING...BRINGING
MORE LOCALLY HEAVY RAIN. RAINFALL TOTALS OF 1 TO 2 INCHES ARE
EXPECTED ACROSS MUCH OF THE AREA...WITH LOCALLY HIGHER AMOUNTS
ACROSS THE SOUTH.
HIGH PRESSURE BUILDS INTO THE REGION TUESDAY NIGHT. COOL CYCLONIC
FLOW EXPECTED FOR THE REMAINDER OF THE WORK WEEK...BRINGING A
CHANCE FOR INSTABILITY SHOWERS WEDNESDAY THROUGH FRIDAY. THE
GREATEST CONCENTRATION OF SHOWERS WILL BE DURING THE AFTERNOON
AND EARLY EVENING HOURS. CAN NOT RULE OUT ISOLATED/SCATTERED
SHOWERS OUTSIDE THIS PERIOD EACH DAY DUE TO WEAK DISTURBANCES
MOVING WITH THE MEAN FLOW.
&&
.AVIATION...FOR 00Z TAF ISSUANCE
ISSUED AT 605 PM CDT SAT MAY 10 2014
A WEAK UPPER LEVEL DISTURBANCE WILL BE LIFTING NORTHEAST ACROSS
WISCONSIN THIS EVENING. DESPITE A VERY DRY AIRMASS IN PLACE...LIGHT
RAIN IS REACHING THE SURFACE OVER SW WISCONSIN. INCLUDED A TEMPO
GROUP OVER CENTRAL AND NORTH-CENTRAL WISCONSIN TO ACCOUNT FOR THESE
SHOWERS...BUT ANTICIPATING CIGS/VSBYS REMAINING VFR. MORE
UNCERTAINTY EXISTS WHETHER ANY SHOWERS COULD SURVIVE THE TRIP INTO
NE WISCONSIN SO LEFT ANY MENTION OF PRECIP OUT OF THE TAFS. THE
LATEST GUIDANCE SUGGESTS A SECONDARY LINE OF SHOWERS AND STORMS WILL
ARRIVE LATE IN THE EVENING OR AFTER MIDNIGHT...BUT WILL LET THE
FORECAST PLAY OUT BEFORE ADDING ANOTHER CHANCE OF RAIN. MAINLY VFR
TOMORROW UNDER SCT TO BKN CIGS. SOME THREAT FOR SHOWERS DEVELOPING
TOMORROW AFTERNOON BUT LEFT OUT OF THE FORECAST.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....TE
LONG TERM......ECKBERG
AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
302 PM CDT FRI MAY 9 2014
.SHORT TERM...(TONIGHT THROUGH SATURDAY NIGHT)
ISSUED AT 302 PM CDT FRI MAY 9 2014
MAIN FORECAST CONCERNS THIS PERIOD...RETURNING SHRA/TSRA CHANCES SAT
AFTERNOON/NIGHT...TEMPERATURES THRU THE PERIOD.
DATA ANALYSIS AT 18Z HAD A BROAD AREA OF LOW PRESSURE CENTERED JUST
NORTHWEST OF LK SUPERIOR AND LIFTING RATHER QUICKLY NORTHEAST INTO
ONT. PRESSURE GRADIENT AROUND THE LOW REMAINED ACROSS MUCH OF MN/WI/
IA WITH BRISK SOUTHWEST TO NORTHWEST WINDS OF 15-25 MPH COMMON.
THESE WINDS USHERING IN COOLER AIR COMBINED WITH 925-850MB MOISTURE/
STRATUS CLOUDS WRAPPED AROUND BEHIND THE LOW MAKING FOR A MUCH
COOLER/GRAYER DAY THAN THURSDAY WAS ACROSS MOST OF THE REGION. -SHRA
WITH THE WRAP AROUND MOISTURE LIMITED TO THE NORTH HALF OF MN WHERE
THE MOISTURE WAS DEEPER TO ABOUT 700MB.
MODEL RUNS OF 09.12Z INITIALIZED WELL AND OFFER QUITE SIMILAR
SOLUTIONS FOR TONIGHT THRU SAT NIGHT AS ONE SHORTWAVE TROUGH EXITS
AND THE NEXT ONE QUICKLY MOVES IN/ACROSS THE UPPER MIDWEST LATE
SAT/SAT NIGHT. TREND IS A BIT STRONGER WITH THIS NEXT SHORTWAVE AS
IT MOVES INTO WESTERN SD/NEB BY 12Z SAT...THEN TOWARD A COMPROMISE
OF THE EARLIER RUNS AS IT MOVES INTO WESTERN MN BY 00Z SUN. BY 12Z
SUN TREND IS FOR MORE SHORTWAVE RIDGING OVER MN/IA/WI BEHIND THIS
DEPARTING WAVE...AND AHEAD OF STRONGER TROUGHING DIGGING INTO THE
CENTRAL/SOUTHERN ROCKIES. WITH THE TIGHTER CONSENSUS...SHORT-TERM
FCST CONFIDENCE IS GOOD THIS CYCLE.
IN THE SHORT TERM THE SFC-850MB LOW WILL LIFT RATHER QUICKLY TO NEAR
JAMES BAY BY 06Z WITH THE SFC RIDGE AXIS APPROACHING THE MS RIVER.
LOWER LEVEL RH PROGS DOING A DECENT JOB ON THE WRAP AROUND STRATUS
CLOUDS AT 18Z. WOULD EXPECT THESE CLOUDS TO CLEAR THE FCST AREA
RATHER QUICKLY THRU THE LATE AFTERNOON/EARLY EVENING WITH THE SFC-
850MB LOW EXITING AND APPROACH OF THE LOWER LEVEL RIDGE AXIS.
HOWEVER ONE FINAL PIECE OF SHORTWAVE ENERGY OVER NORTHWEST MN TO
ROTATE ACROSS NORTHERN WI THIS EVENING LOOKS TO DELAY THAT A BIT
ESPECIALLY OVER THE NORTHEAST END OF THE FCST AREA. A PERIOD OF
CLEAR SKIES/LIGHT WINDS EXPECTED LATER TONIGHT AS THE SFC-700MB
RIDGE AXIS MOVES BY. GIVEN THIS...THE COOL/GRAY DAY AND THE RECENT
RAINS...WILL HAVE TO WATCH FOR PATCHY FOG DEVELOPMENT LATE TONIGHT.
FOCUS SAT SHIFTS BACK TO THE WEST AND NEXT APPROACHING SHORTWAVE.
LOWER LEVEL WARM ADVECTION/MOISTURE TRANSPORT ALREADY ARRIVE SAT
MORNING...WITH THE 925-850MB WARM ADVECTION OUTPACING THE ARRIVAL OF
THE INCREASING MOISTURE IN THOSE LAYERS. SOME 700MB MOISTURE ARRIVES
EARLIER...BUT LITTLE IN THE WAY OF LIFT THRU 700MB SEEN UNTIL SAT
AFTERNOON. WILL LEAVE SAT MORNING DRY AND CONTINUED TO SPREAD THE
RAIN CHANCES INTO/ACROSS THE FCST AREA SAT AFTERNOON. STRONGER OF
THE LOW LEVEL FORCING/DEEPEST OF THE MOISTURE...PW VALUES AROUND
0.75 INCH...SPREADS ACROSS THE AREA SAT EVENING WITH THE MID LEVEL
TROUGH AXIS. CARRIED HIGHEST SHRA/TSRA CHANCES OF 40-60 PERCENT SAT
EVENING...TAPERING DOWN AFTER MIDNIGHT AS THE 925-500MB TROUGH AXIS
PASSES AND MOISTURE/LIFT DECREASE. MODEL SOUNDINGS SHOWING SKINNY
CAPE PROFILES OF 100-500 J/KG BETWEEN ROUGHLY 700-350MB SAT
AFTERNOON/EVENING...DIMINISHING LATE SAT NIGHT. INCLUDED TSRA
CHANCES SAT AFTERNOON/NIGHT. USED A BLEND OF THE NUMERICAL GUIDANCE
LOWS/HIGHS FOR TONIGHT THRU SAT NIGHT.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 302 PM CDT FRI MAY 9 2014
MAIN FORECAST CONCERNS FOR SUN THRU MON NIGHT...SHRA/TSRA CHANCES
MUCH OF THE PERIOD AND RAIN AMOUNTS.
09.12Z MODELS IN GOOD AGREEMENT AS STRONG TROUGHING/SHORTWAVE ENERGY
MOVES THRU THE ROCKIES SUN THEN BEGINS TO EJECT INTO THE CENTRAL/
SOUTHERN PLAINS SUN NIGHT. TREND IS TOWARD SLOWER/STRONGER OF THE
EARLIER MODELS WITH THIS TROUGH SUN/SUN NIGHT. TREND MON/MON NIGHT
AS THE TROUGH MOVES INTO THE CENTRAL CONUS IS TOWARD A COMPROMISE OF
THE EARLIER RUNS WITH ECMWF SPEEDING UP AND GFS SLOWING DOWN. CAN-
GEM REMAINS A SLOW LOOKING OUTLIER WITH THE TROUGH AT 12Z TUE. THE
TIGHTENING ECMWF/GFS CONSENSUS FOR SUN-MON NIGHT LEADS TO AVERAGE TO
GOOD CONFIDENCE IN THIS FCST PERIOD.
BREAK FROM THE SHRA/TSRA CHANCES BEHIND THE SAT/SAT NIGHT SYSTEM
CONTINUES TO LOOK BRIEF. 925-700MB WARM ADVECTION/ISENTROPIC LIFT
AND MOISTURE TRANSPORT...AHEAD OF THE NEXT CO/KS LEE LOW IN RESPONSE
TO THE STRONG TROUGHING COMING THRU THE ROCKIES...ALREADY SPREADS
NORTHEAST INTO THE UPPER MIDWEST SUN MORNING. NAM WITH MORE
SHORTWAVE ENERGY RIPPLING OUT OF THE WESTERN TROUGH AND INTO THE
REGION SUN AND FLATTER/FASTER 850-500MB FLOW. NAM THUS STREAMS THE
MOISTURE/LIFT NORTHEAST MORE QUICKLY AND SPREADS PRECIP ACROSS THE
FCST AREA ALREADY SUN MORNING. INITIALLY QUITE A BIT OF DRY AIR
BETWEEN 800-600MB TO OVERCOME BEFORE PRECIP CHANCES WOULD INCREASE
WITH NAM LOOKING TOO FAST WITH MOISTURE/PRECIP INTO THE AREA. SIDED
WITH THE SLOWER GFS/ECMWF/CAN-GEM CONSENSUS AND ONLY SPREAD 20-40
PERCENT SHRA/TSRA CHANCES INTO THE SOUTH HALF OF THE FCST AREA SUN
MORNING. BY SUN AFTERNOON ALL MODELS SPREAD 1 TO 1.5 INCHES OF PW
INTO THE AREA...WITH MORE SATURATION IN THE 925-700MB LAYER AND
INCREASING LIFT/DIVERGENCE ALOFT AHEAD OF THE MID LEVEL TROUGH.
RATHER DEEP LAYERED WEAK TO MDT LIFT SPREADS ACROSS THE AREA SUN
NIGHT MON AS THE MID LEVEL TROUGH EJECTS INTO THE PLAINS AND THE SFC-
850MB LOW LIFTS TOWARD/INTO THE UPPER MIDWEST. THIS WITH THE 1 TO
1.5 INCH PW VALUES. RAISED PRECIP CHANCES MON TO 70-80 PERCENT SUN
NIGHT AND AROUND 70 PERCENT MON. CARRIED 50-70 PERCENT RAIN CHANCES
YET MON NIGHT WITH THE SLOWING TREND AND SIGNAL FOR THE SFC THRU MID
LEVEL TROUGH TO STILL BE OVER OR WEST OF THE AREA...AT LEAST THRU
THE EVENING. MODEL SOUNDINGS AS MUCH AS 250-1K J/KG MUCAPE OVER THE
SUN/MON AFTERNOONS...BUT AGAIN LIKE SAT GENERALLY A SKINNY CAPE
PROFILE. GIVEN THE HIGH PW VALUES AND BROAD/DEEP FORCING/LIFT...
CARRIED TSRA CHANCES FROM SUN AFTERNOON THRU MON NIGHT. BLEND OF THE
NUMERICAL GUIDANCE FOR HIGHS/LOWS SUN THRU MON NIGHT LOOKS GOOD.
THE DURATION OF THE FORCING/LIFT AND HIGH PW VALUES RAISE THE
CONCERN FOR MORE WIDESPREAD MDT TO HEAVY RAINS OF 1 TO 2 INCHES FROM
SUN NIGHT INTO MON NIGHT. THIS BEARS WATCHING AS FAR AS HYDROLOGY
CONCERNS AND MANY RIVERS IN THE AREA ALREADY RUNNING HIGH. STILL
PLENTY OF MODEL DETAIL DIFFERENCES AS FAR AS THE HEAVY RAIN
POTENTIAL. WILL HOLD OFF ON AN ESF FOR NOW BUT PASS ALONG THOUGHTS
THE THE MIDNIGHT CREW.
FOR TUESDAY THROUGH FRIDAY.../DAYS 4 TO 7/...
MAIN CONCERNS THIS PERIOD...PERIODIC SHRA CHANCES AND BELOW/MUCH
BELOW NORMAL TEMPERATURES.
09.00Z AND 09.12Z MEDIUM RANGE MODELS CONTINUE TO SLOWLY COME
INTO BETTER AGREEMENT AS A DEEP MID LEVEL TROUGH/LOW DRIFTS SLOW
EAST ACROSS CENTRAL NOAM IN THE TUE-FRI PERIOD. GFS REMAINS A BIT
FASTER THAN THE OTHERS WHILE CAN-GEM IS THE SLOWER OF THE LOT.
ECMWF/ENSEMBLE MEANS OFFER A COMPROMISE ON THE PROGRESSIVENESS OF
THE TROUGH TUE-THU. OVERALL CONSENSUS CONTINUES TO TREND TOWARD A
SLOWER/STRONGER TROUGH/MID LEVEL LOW THAN THE EARLIER 08.00Z/
09.00Z RUNS. DAY 4-7 FCST CONFIDENCE AVERAGE THIS CYCLE.
GOOD CONSENSUS TUE FOR THE SFC-850MB LOW/TROUGH FROM SUN/MON TO BE
LIFTING NORTH/EAST OF THE FCST AREA...WITH THE UPPER MIDWEST
DOMINATED BY LOW LEVEL COLD ADVECTION/MUCH COLDER 925-850MB AIR.
GFS/ECMWF HAVE 850MB TEMPS IN THE +3C TO 0C RANGE BY 00Z WED. THIS
AHEAD OF THE 500MB TROUGH AXIS...AS THE TROUGH DEEPENS INTO THE
NORTH-CENTRAL CONUS. FAVORING THE CONSENSUS...THE TROUGH AXIS SHIFTS
EAST AND IS OVER MN/IA/WI WED/THU...WITH 850MB TEMPS OVER THE FCST
AREA BOTTOMING OUT IN THE -2C TO -5C RANGE AT 12Z THU. THE MID LEVEL
TROUGH AXIS SHIFTS EAST OF THE REGION FRI...LEAVING THE UPPER
MIDWEST UNDER ACTIVE/UNSETTLED NORTHWEST FLOW ALOFT. NUMEROUS
DIFFICULT TO TIME SHORTWAVES PROGGED TO ROTATE AROUND/THRU THE DEEP
MID LEVEL TROUGH OR NORTHWEST FLOW OVER THE REGION IN THE TUE-FRI
PERIOD. THIS WITH THE MUCH COLDER THAN NORMAL 850-700MB AIRMASS...
STEEP SFC-700MB LAPSE RATES AND MODEST 850-700MB MOISTURE OVER THE
AREA. THUS EACH OF THESE SHORTWAVES WOULD BE CAPABLE OF PRODUCING
SCT -SHRA ACROSS THE AREA. UNTIL A BETTER SHORTWAVE TIMING CONSENSUS
IS REACHED...SMALL -SHRA CHANCE MUCH OF THE TUE-FRI PERIOD
REASONABLE FOR NOW. 850MB TEMPS MUCH OF THE PERIOD LOOKING TO BE IN
THE 1 TO 2 STANDARD DEVIATIONS BELOW NORMAL RANGE...WITH TUE-FRI
HIGHS/LOWS AROUND 10F BELOW NORMAL. IF LIGHT WINDS/MOSTLY CLEAR
SKIES WOULD PREVAIL FOR THE OVERNIGHT HOURS...SOME FROST WOULD BE
POSSIBLE...ESPECIALLY WED/THU/FRI MORNINGS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1213 PM CDT FRI MAY 9 2014
LOOKING AT THE 09.15Z RAP AND 09.12Z NAM LOW LEVEL RH INDICATES THE
LOW CLOUDS OVER THE AREA SHOULD REMAIN IN PLACE THROUGH THE
AFTERNOON. EXPECT TO SEE THE CEILINGS SLOWLY IMPROVE TO ALMOST VFR
BY LATE AFTERNOON AND THEN THE MOISTURE SHOULD QUICKLY DISSIPATE
EARLY THIS EVENING ALLOWING THE CLOUDS TO SCATTER OUT. THE GUSTY
WINDS WILL ALSO SETTLE DOWN EARLY THIS EVENING AS THE LOW LEVEL
INVERSION DEVELOPS. HIGH PRESSURE WILL BRIEFLY BE OVER THE AREA
TONIGHT FOR CLEAR SKIES AND LIGHT WINDS WITH THE DIRECTION COMING
AROUND TO THE SOUTH AS THE RIDGE AXIS GOES BY. ANOTHER SHORT WAVE
TROUGH WILL BE APPROACHING FROM THE SOUTHWEST SATURDAY. THE NAM
SUGGESTS MID LEVEL MOISTURE AND A HIGH VFR CEILING COULD DEVELOP
ALREADY BY 18Z SATURDAY WHILE THE 09.12Z GFS IS A LITTLE SLOWER TO
BRING THIS MOISTURE IN. FOR NOW...WILL JUST SHOW A SCATTERED MID
LEVEL DECK BUT THE NEXT FORECAST WILL HAVE TO SHOW A CEILING AND MAY
HAVE TO INTRODUCE SOME VICINITY SHOWERS FOR SATURDAY AFTERNOON.
&&
.HYDROLOGY...
ISSUED AT 302 PM CDT FRI MAY 9 2014
MINOR FLOODING CONTINUES ALONG PORTIONS OF THE MS RIVER FROM WABASHA
MN TO GUTTENBERG IA. SAT THRU MON NIGHT WILL BRING AT LEAST 2 MORE
ROUNDS OF RAIN. RAIN AMOUNTS LATER SAT AND SAT NIGHT LOOK TO MOSTLY
BE 1/4 INCH OR LESS. AMOUNTS OF AN INCH OR 2 APPEAR POSSIBLE DURING
THE SUN NIGHT/MON PERIOD. THESE RAINS COULD HAVE ADDITIONAL IMPACTS
ON BOTH TRIBUTARIES AND THE MS RIVER...SLOWING THE RATES OF FALL OR
PRODUCE ADDITIONAL RISES.
CHECK THE LATEST HYDROLOGIC STATEMENTS FOR THE DETAILS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...RRS
LONG TERM....RRS
AVIATION.....04
HYDROLOGY....RRS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1213 PM CDT FRI MAY 9 2014
.SHORT TERM...(TODAY THROUGH SATURDAY)
ISSUED AT 250 AM CDT FRI MAY 9 2014
BULK OF SHOWERS/STORMS HAVE SHIFTED NORTH/EAST EARLY THIS
MORNING...WITH THE LOW LEVEL JET/MOISTURE TRANSPORT FEEDING THE PCPN
NOSING TOWARD THE EASTERN GREAT LAKES.
LOW PRESSURE SYSTEM/COLD FRONT THAT HELPED TRIGGER THE RAINFALL WILL
CONTINUE TO TRACK NORTHEAST THIS MORNING...WITH THE BOUNDARY RUNNING
NORTH-SOUTH ACROSS EASTERN WI BY THIS AFTERNOON. MOISTURE WRAPPED
AROUND THE LOW...COUPLED WITH COLDER AIR A LOFT/FAVORABLE LAPSE
RATES...COULD RESULT IN SHOWERS ACROSS NORTHERN WI THIS AFTERNOON.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 250 AM CDT FRI MAY 9 2014
UNSETTLED WEATHER PATTERN WILL RESULT IN PERIODS OF SHOWERS AND
THUNDERSTORMS FROM SATURDAY NIGHT INTO MONDAY.
UPPER LEVEL SHORTWAVE TROUGH SLATED TO LIFT NORTHEAST OUT OF THE
CENTRAL PLAINS AND ACROSS THE REGION SAT NIGHT. WEAK 850-700 MB WARM
ADVECTION WITH THE SHORTWAVE...WITH THE NOSE OF THE 850 MB MOISTURE
TRANSPORT POINT LEADING IT ACROSS THE AREA. INSTABILITY WEAK...BUT
ENOUGH TO AID IN SHOWER/STORM DEVELOPMENT. TRACK/PLACEMENT OF THE
WEATHER FEATURES FAVORS MN INTO NORTHERN WI FOR THE HIGH RAIN
CHANCES.
BROAD...LONGWAVE UPPER LEVEL TROUGH STARTS TO MOVE OUT OF THE
ROCKIES SUNDAY...WITH BIT OF ENERGY SPINNING OUT OF THE TROUGH
TOWARD THE GREAT LAKES. NAM/GFS RUN A SFC BOUNDARY FROM A LOW OVER
THE SOUTHERN PLAINS...NORTHWARD INTO THE UPPER MISSISSIPPI RIVER
VALLEY. STRONG SURGE OF LOW LEVEL MOISTURE RUNS ALONG/AHEAD OF
THIS...WITH A 40 KT LOW LEVEL JET NOSING IT INTO SOUTHERN WI BY 00Z
MON. THE BULK OF THE INSTABILITY IS EXPECTED TO STAY SOUTH OF THE
LOCAL FORECAST AREA...BUT 0-6 KM SHEAR OF ABOUT 40 KTS FOR SUNDAY
NIGHT. THERE WILL BE A SEVERE THREAT TO THE SOUTH...BUT THIS COULD
CREEP INTO NORTHEAST IA/SOUTHWEST WI. A SMALL ADJUSTMENT IN
PLACEMENT OF THE FRONT/TIMING COULD EXPAND THAT THREAT FURTHER - ITS
A PERIOD OF WATCH.
ROUNDS OF SHOWERS/STORMS WILL CONTINUE INTO MONDAY AS THE SFC LOW
TRACKS INTO THE REGION AND ANOTHER SHORTWAVE SLIDES OUT OF THE MEAN
UPPER LEVEL TROUGH. MID LEVEL DRY PUNCH BEHIND THE SFC LOW MOVES IN
MONDAY NIGHT...AND SHOULD SEE AN END TO THE RAIN CHANCES UNTIL WED.
FOR WEDNESDAY...THE AXIS OF THE UPPER LEVEL TROUGH PUSHES OVER THE
UPPER MISSISSIPPI RIVER VALLEY...WHILE MODELS HINT THAT A SFC TROUGH
WILL HANG WELL WEST/SOUTH OF THE DEPARTING SFC LOW. ABOUT 500 J/KG
OF MUCAPE VIA THE GFS TO PLAY WITH...AND THE EC/GFS BOTH GENERATE
SOME PCPN. ANOTHER PIECE OF ENERGY PROGGED TO STREAK DOWN THE
BACKSIDE OF THE TROUGH ON THU...WITH A FEW MORE SHOWERS POSSIBLE.
LITTLE/IF ANY INSTABILITY INDICATED AT THIS TIME.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1213 PM CDT FRI MAY 9 2014
LOOKING AT THE 09.15Z RAP AND 09.12Z NAM LOW LEVEL RH INDICATES
THE LOW CLOUDS OVER THE AREA SHOULD REMAIN IN PLACE THROUGH THE
AFTERNOON. EXPECT TO SEE THE CEILINGS SLOWLY IMPROVE TO ALMOST VFR
BY LATE AFTERNOON AND THEN THE MOISTURE SHOULD QUICKLY DISSIPATE
EARLY THIS EVENING ALLOWING THE CLOUDS TO SCATTER OUT. THE GUSTY
WINDS WILL ALSO SETTLE DOWN EARLY THIS EVENING AS THE LOW LEVEL
INVERSION DEVELOPS. HIGH PRESSURE WILL BRIEFLY BE OVER THE AREA
TONIGHT FOR CLEAR SKIES AND LIGHT WINDS WITH THE DIRECTION COMING
AROUND TO THE SOUTH AS THE RIDGE AXIS GOES BY. ANOTHER SHORT WAVE
TROUGH WILL BE APPROACHING FROM THE SOUTHWEST SATURDAY. THE NAM
SUGGESTS MID LEVEL MOISTURE AND A HIGH VFR CEILING COULD DEVELOP
ALREADY BY 18Z SATURDAY WHILE THE 09.12Z GFS IS A LITTLE SLOWER TO
BRING THIS MOISTURE IN. FOR NOW...WILL JUST SHOW A SCATTERED MID
LEVEL DECK BUT THE NEXT FORECAST WILL HAVE TO SHOW A CEILING AND
MAY HAVE TO INTRODUCE SOME VICINITY SHOWERS FOR SATURDAY
AFTERNOON.
&&
.HYDROLOGY...
ISSUED AT 250 AM CDT FRI MAY 9 2014
WATER CONTINUES HIGH ALONG THE MISSISSIPPI RIVER...WITH A FEW
LOCATIONS STILL IN OR NEAR FLOOD. IN ADDITION TO THE RAINFALL OF
YESTERDAY...SATURDAY THROUGH MONDAY WILL BRING A FEW MORE ROUNDS OF
RAIN. AMOUNTS COULD EXCEED AN INCH. THIS COULD HAVE ADDITIONAL
IMPACTS...SLOWING RATES OF FALL...OR PRODUCE ADDITIONAL RISES.
CHECK THE LATEST HYDROLOGIC STATEMENTS FOR THE DETAILS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...RIECK
LONG TERM....RIECK
AVIATION...04
HYDROLOGY....RIECK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1140 PM CDT THU MAY 8 2014
.UPDATE...
ISSUED AT 1021 PM CDT THU MAY 8 2014
ONE LAST BATCH OF SHOWERS AND THUNDERSTORMS ARE MOVING ACROSS
SOUTHEAST MINNESOTA AND NORTHEAST IOWA. 0-3KM/MLCAPE HAS BEEN
DROPPING OVER THE PAST FEW HOURS AND EXPECT THAT TREND TO CONTINUE
THROUGH THE REST OF THE NIGHT. BASED ON 09.01Z RAP ANALYSIS...IT
ALSO APPEARS THAT THESE STORMS ARE OCCURRING IN A RELATIVE MINIMUM
OF 0-6KM SHEAR AS WELL. THUS...EXPECT THAT STORMS SHOULD REMAIN
SUB-SEVERE FROM HERE ON OUT THROUGH THE REST OF TONIGHT.
TEMPERATURES WILL REMAIN MILD IN THE UPPER 60S UNTIL THE COLD
FRONT PUSHES THROUGH TOWARD DAYBREAK WITH CONVECTION NOT EXPECTED
ALONG THIS FRONT.
&&
.SHORT TERM...(TONIGHT THROUGH FRIDAY NIGHT)
ISSUED AT 241 PM CDT THU MAY 8 2014
MAIN FORECAST CONCERNS THIS PERIOD...SHRA/TSRA/SEVERE CHANCES THRU
THIS EVENING...LINGERING -SHRA CHANCES FRI...TEMPERATURES.
18Z DATA ANALYSIS HAD A 1000MB LOW OVER NORTHEAST NEB WITH A TROUGH
NORTHEAST INTO NORTHWEST WI AND WARM FRONT ARCING EAST ACROSS
NORTHERN IA INTO SOUTHERN WI. WARM FRONT CONTINUES TO SEPARATE TO
DISTINCT AIRMASSES...70S WITH DEW POINTS IN THE 60S SOUTH OF THE
WARM FRONT...60S WITH DEW POINTS IN THE 50S. SB CAPE SOUTH OF THE
FRONT IN THE 1500-2500 J/KG RANGE...ELEVATED 500-1000 J/KG NORTH OF
THE WARM FRONT. AREA WSR-88D/S SHOWING CONVECTION DEVELOPING/
EXPANDING ACROSS THE SOUTH HALF OF IA...WITH/AHEAD OF SHORTWAVE
ENERGY LIFTING UP THE EAST SIDE OF THE MID LEVEL LONG WAVE TROUGH.
08.12Z MODELS GENERALLY INITIALIZED WELL. GFS AGAIN ABOUT 5F HIGH
WITH SFC DEW POINTS IN THE MOISTURE PLUME COMING NORTH THRU THE
MID MS VALLEY. SOLUTIONS CONVERGING ON A TIGHT COMPROMISE
CONSENSUS OF THE EARLIER RUNS AS THE TROUGHING/ENERGY OVER THE
ROCKIES/PLAINS LIFTS NORTHEAST THRU THE UPPER MIDWEST TONIGHT
THRU FRI NIGHT. STILL SOME LOWER LEVEL DETAIL DIFFERENCES ON
CONVECTION EVOLUTION THRU THIS EVENING...BUT AFTER THAT SOLUTIONS
QUITE SIMILAR FOR LATER TONIGHT THRU FRI NIGHT AS COOLER/DRIER AIR
SPREADS IN BEHIND THE PASSING LOW/COLD FRONT. FCST CONFIDENCE
GENERALLY GOOD FOR TONIGHT THRU FRI NIGHT.
FOR THE SHORT TERM...AS OF EARLY THIS AFTERNOON...CONVECTIVE SCENARIO
FOR LATER THIS AFTERNOON/THIS EVENING REMAINS IN QUESTION. MAIN FOCUS
FOR TSRA DEVELOPMENT REMAINS WESTERN IA/SOUTHWEST MN...NEAR THE SFC
LOW/TROUGH/FRONTS AND CLOSER TO THE STRONGER SHORTWAVE LIFTING
TOWARD EASTERN SD. SHRA/TSRA DEVELOPING/SPREADING NORTH ACROSS
IA...ALONG WITH THE CLOUD COVER CONSUMING/LIMITING CAPE EARLY THIS
AFTERNOON AND MUDDYING THE TSRA/SEVERE EVOLUTION FOR LATER THIS
AFTERNOON/EVENING. LOWER LEVEL CONVERGENCE/FORCING WOULD POINT TO A
LINE OF STRONG/SEVERE TSRA DEVELOPING IN WESTERN IA/SOUTHWEST MN
THEN LIFTING NORTHEAST ACROSS MN/IA/WI IN THE 21Z-04Z TIME-FRAME.
STRONGEST 0-6KM BULK SHEAR OF 30-60KTS IS OVER THE WEST PORTIONS OF
THE FCST AREA THIS AFTERNOON AND NORTHWEST PORTIONS OF THE FCST AREA
THIS EVENING. SWODY1 SEEMS TO HAVE THE THREATS/RISKS LAYED OUT
WELL...BASED ON CONVECTION LIFTING NORTH ACROSS IA NOT INTERFERING
TOO MUCH. WILL STAY THE COURSE WITH HIGHEST SHRA/TSRA CHANCES LATER
THIS AFTERNOON/EVENING WITH WHAT SHOULD BE A LINE OF CONVECTION
MOVING EAST/NORTHEAST ACROSS THE FCST AREA WITH/AHEAD OF THE SFC-
850MB TROUGH/COLD FRONT. SEE SWODY1 FOR MORE DETAILS ON THE SEVERE
THREATS THRU THIS EVENING.
925-850MB COLD ADVECTION/DRYING SPREAD RATHER QUICKLY ACROSS THE
FCST AREA LATE THIS EVENING/OVERNIGHT AS THE SFC-850MB LOW LIFTS
INTO NORTHEAST MN. PW VALUES OF 1 TO 1.5 INCHES AT 00Z FRI ARE HALF
THAT BY 12Z FRI. THIS AND PASSAGE OF THE SFC-850MB TROUGH/FRONT
SWEEP THE BULK OF THE SHRA/TSRA EAST AND OUT OF THE FCST AREA BY 12Z
FRI. ONLY SOME SMALL LINGERING -SHRA CHANCES IN THE EAST/NORTH ENDS
OF THE FCST AREA BY 12Z FRI. A SECONDARY SHORTWAVE TO LIFT ACROSS
THE AREA FRI AFTERNOON ALONG WITH SOME 850-700MB WRAP-AROUND/
DEFORMATION BAND MOISTURE. DEEPEST OF THIS MOISTURE ACROSS THE NORTH
END OF THE FCST AREA...WITH STEEP LOW LEVEL LAPSE RATES AND WEAK
INSTABILITY TO ABOUT 750MB. CONTINUED THE SMALL -SHRA CHANCES ACROSS
MAINLY THE NORTHEAST 1/3 OF THE FCST AREA THRU FRI AFTERNOON...WHICH
BLENDS WELL WITH NEIGHBORING GRIDS. LOSS OF DIURNAL HEATING AND
PASSING OF THE SECOND SHORTWAVE QUICKLY PUTS AN END TO THIS AND LEFT
FRI NIGHT DRY AS HIGH PRESSURE AND SHORTWAVE RIDGING ALOFT BUILD
INTO THE REGION. A COOLER PERIOD TONIGHT THRU FRI NIGHT AS A COOL
925MB AIRMASS SETTLES OVER THE REGION. WINDS/CLOUDS TO KEEP LOWS
TONIGHT ABOVE NORMAL. BELOW NORMAL HIGHS FRI UNDER THE COOL 925MB
AIRMASS. BELOW NORMAL LOWS FRI NIGHT UNDER MOSTLY CLEAR SKIES/LIGHT
WINDS. USED THE MODEL/ENSEMBLE CONSENSUS LOWS/HIGHS FOR TONIGHT THRU
FRI NIGHT.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 241 PM CDT THU MAY 8 2014
MAIN FORECAST CONCERNS FOR SAT THRU SUN NIGHT...SHRA/TSRA CHANCES
THRU THE PERIOD AS MORE TROUGHING/SHORTWAVES TAKE AIM AT THE UPPER
MIDWEST.
DECENT AGREEMENT AMONG THE 08.12Z MODELS CONTINUES SAT AS THE NEXT
STRONGER SHORTWAVE TRACKS INTO MN BY LATE IN THE DAY. IMPROVING
CONSENSUS FOR RISING HGTS/SHORTWAVE RIDGING TO BUILD ACROSS THE
UPPER MIDWEST LATER SAT/SAT NIGHT...AHEAD OF THE NEXT STRONG/LONG
WAVE TROUGH TO DIG INTO THE WESTERN CONUS. TREND CONTINUES STRONGER
WITH THIS NEXT TROUGHING INTO THE ROCKIES SAT NIGHT/SUN THEN
EJECTING INTO THE WESTERN PLAINS SUN NIGHT. SHORTWAVE RIDGE AXIS
THAT BUILDS OVER THE REGION SAT NIGHT QUICKLY MOVES EAST SUN...WITH
THE REGION ALREADY UNDER THE INFLUENCE OF SOUTHWEST FLOW ALOFT AHEAD
OF THE NEXT TROUGH FOR SUN AFTERNOON/NIGHT. WITH RUN-TO-RUN
CONSISTENCY AND THE IMPROVING CONSENSUS...SAT THRU SUN NIGHT FCST
CONFIDENCE IS AVERAGE TO GOOD.
BREAK BETWEEN SYSTEMS FRI NIGHT INTO SAT IS BRIEF. THE NEXT
SHORTWAVE INTO MN LATER SAT QUICKLY SPREADS INCREASING LOWER LEVEL
THERMO-DYNAMIC FORCING/LIFT AND INCREASING MOISTURE/THETA-E
CONVERGENCE INTO THE FCST AREA THRU THE DAY ON SAT. INITIAL
MOISTURE/LIFT GOES INTO SATURATION SAT MORNING...WITH INCREASING
SHRA CHANCES INTO SAT AFTERNOON/EVENING AS THE DEEPEST MOISTURE/
STRONGER OF THE LIFT MOVES ACROSS. CARRIED HIGHEST RAIN CHANCES
LATER SAT AFTERNOON/EVENING...THE LOWER LATER SAT NIGHT BEHIND THE
SFC-850MB TROUGH AXIS. INDICATIONS FOR 250 TO AS MUCH AS 1K J/KG MU
CAPE INTO THE AREA AT 00Z SUN SO CONTINUED TSRA MENTION FOR MUCH OF
THE FCST AREA SAT AFTERNOON/EVENING. NEXT BREAK BETWEEN SYSTEMS IS
ALSO RATHER BRIEF LATER SAT NIGHT/SUN MORNING. WITH THE PROGRESSIVE
AND ACTIVE FLOW...THE UPPER MIDWEST IS BACK UNDER SOUTHWEST FLOW
ALOFT SUN AFTERNOON/NIGHT...AHEAD OF STRONG MID LEVEL TROUGHING
SWINGING THRU THE CENTRAL/SOUTHERN ROCKIES. INCREASING MOISTURE/
LIFT/INSTABILITY QUICKLY SPREAD BACK INTO THE FCST AREA FOR SUN
AFTERNOON/NIGHT. PW VALUES IN THE 1 INCH PLUS RANGE BY 00Z MON...
AHEAD OF THE NEXT STRONGER SHORTWAVE AND SFC-850MB LOW LIFTING
NORTHEAST TOWARD/INTO THE UPPER MIDWEST SUN NIGHT. RAISED SHRA/TSRA
CHANCES INTO THE 35-55 PERCENT RANGE SUN AFTERNOON AND 55-70 PERCENT
RANGE SUN NIGHT. SOME LOCALLY HEAVY RAINS POSSIBLE SUN NIGHT...
DEPENDING ON WHERE THE SFC LOW TRACKS/SFC BOUNDARIES SET UP. DUE TO
SOME UNCERTAINTIES WITH WHAT WOULD BE TIMING OF SHRA/TSRA IN/AROUND
THE AREA AND CLOUD COVER...USED THE MODEL/ENSEMBLE CONSENSUS HIGHS/
LOWS FOR SAT THRU SUN NIGHT.
FOR MONDAY THROUGH THURSDAY.../DAYS 4 TO 7/...
MAIN FORECAST CONCERNS THIS PERIOD...SHRA/TSRA CHANCES/RAIN AMOUNTS
MON/MON NIGHT...SHRA CHANCES/COOLER TEMPS TUE-THU.
MEDIUM RANGE MODEL RUNS OF 08.00Z AND 08.12Z ALL SHOW THE SCENARIO
OF STRONG TROUGHING MOVING INTO THE CENTRAL CONUS MON. GFS REMAINS
FASTER THAN ECMWF/CAN-GEM. GOOD CONSENSUS FOR THE STRONG TROUGHING
TO THEN VERY SLOWLY MOVE INTO/ACROSS THE MID/UPPER MS VALLEY TUE
THRU THU...WITH CAN-GEM THE SLOWER/STRONGER OUTLIER BY WED. OVERALL
TREND IS SLOWING AND STRONGER WITH THE MID CONUS TROUGHING NEXT
WEEK. EVEN WITH SOME DIFFERENCES AMONG THE MODELS FOR MON-THU THE
SENSIBLE WEATHER OUTCOMES ARE MORE SIMILAR THAN ONE WOULD USUALLY
EXPECT. DAY 4-7 FCST CONFIDENCE IS AVERAGE WITH RAIN CHANCES THRU
THE PERIOD BUT GOOD FOR BELOW NORMAL TEMPS FOR TUE-THU.
EVEN WITH THE DIFFERENCES ON PROGRESSION OF THE LONG-WAVE TROUGH
ON MON...GOOD CONSENSUS FOR A STRONG PIECE OF ENERGY TO BE LIFTING
NORTHEAST ACROSS THE UPPER MIDWEST MON/MON NIGHT. RATHER STRONG
SFC LOW PROGGED TO ACCOMPANY THIS SHORTWAVE NORTHEAST ACROSS THE
REGION MON. WITH PW VALUES OF AN INCH OR MORE...SHRA/TSRA CHANCES
IN THE 40-65 PERCENT RANGE MON/MON NIGHT LOOK GOOD. POTENTIAL FOR
1 TO 2 INCHES OF RAIN FROM LATER SUN NIGHT THRU MON NIGHT. COLDER
AIR POURS IN FOR TUE THRU THU AS THE THE NORTHERN STREAM PORTION
OF THE MID LEVEL TROUGH SETTLES INTO THE UPPER MIDWEST. 850MB
TEMPS FALL TO A FEW DEGREES EITHER SIDE OF 0C FOR MUCH OF TUE-
THU...SOME 1 TO 2 STANDARD DEVIATIONS BELOW NORMAL. AFTER MORE
NORMAL EARLY MAY TEMPS THROUGH THE WEEKEND...TEMPS FOR TUE-THU
TREND AROUND 10F BELOW NORMAL. WITH THIS COLD CORE OF AIR ALOFT...
STEEP LOW-MID LEVEL LAPSE RATE AND SHORTWAVES ROTATING THRU THE
TROUGH WITH ROUNDS OF INCREASED MOISTURE/FORCING...SMALL -SHRA
CHANCES MUCH OF THE TUE-THU PERIOD REASONABLE FOR NOW. GIVEN THE
TIMING/DETAIL UNCERTAINTIES...DID NOT STRAY MUCH FROM THE MODEL/
ENSEMBLE CONSENSUS HIGHS/LOWS AND RAIN CHANCES FOR DAYS 4-7.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1140 PM CDT THU MAY 8 2014
WITH MOST OF THE RAIN AND STORMS HAVING MOVED OFF TO THE
EAST...THE MAIN FOCUS IS ON THE IFR CEILINGS LINGERING BEHIND THE
COLD FRONT/SURFACE LOW. THIS COLD FRONT WILL MOVE THROUGH SHORTLY
AFTER MIDNIGHT WITH WINDS COMING AROUND TO THE SOUTHWEST TO WEST.
AS THEY DO...THE IFR DECK THAT IS CURRENTLY IN WESTERN MINNESOTA
WILL MOVE EAST OVERNIGHT AND SIT OVER RST/LSE THROUGH MUCH OF THE
MORNING. FORECAST SOUNDINGS SHOW SOME MIXING OCCURRING BY EARLY
AFTERNOON AS DRIER AIR MOVES IN.
&&
.HYDROLOGY...
ISSUED AT 241 PM CDT THU MAY 8 2014
FLOODING CONTINUES ALONG THE MISSISSIPPI RIVER...WITH LOCATIONS
CRESTING BETWEEN GENOA AND LANSING. SHOWERS AND THUNDERSTORMS TODAY
WILL PRODUCE ANYWHERE FROM A HALF INCH TO ONE INCH OF RAIN. THIS
WILL LIKELY SLOW THE FALL FOR LOCATIONS NORTH OF MCGREGOR...AND MAY
INCREASE CRESTS SLIGHTLY SOUTH OF MCGREGOR.
POTENTIAL FOR 1 TO 2 INCHES OF RAINFALL FROM LATE SUN NIGHT THRU
MON EVENING. THIS COULD HAVE ADDITIONAL IMPACTS AND PRODUCE
ADDITIONAL RISES ON AREA RIVERS ALREADY RUNNING HIGH FROM THE
ABOVE AND MUCH ABOVE NORMAL RAINS OF APRIL.
CHECK OUT THE LATEST HYDROLOGIC STATEMENTS FOR THE DETAILS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...HALBACH
SHORT TERM...RRS
LONG TERM....RRS
AVIATION...HALBACH
HYDROLOGY....RRS
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1137 PM MDT THU MAY 8 2014
.UPDATE...
ISSUED AT 833 PM MDT THU MAY 8 2014
LATEST RADAR LOOP WAS SHOWING SHOWERS CONTINUING TO FLARE UP
ACROSS EXTREME SOUTHEAST WYOMING MAINLY ALONG AND EAST OF THE
LARAMIE RANGE DUE TO A COOL DOME ALOFT AND UPSLOPE FLOW PROMOTING
THE INSTABILITY. THE MODELS ARE CONTINUING TO ADVERTISE THIS DOME
OF COOL AIR SHIFTING EAST OVERNIGHT WHICH SHOULD ALLOW FOR MORE
SUBSIDENCE TO MOVE INTO SOUTHEAST WYOMING. HOWEVER...I AM A LITTLE
LEARY ABOUT YANKING THE POPS COMPLETELY UNTIL 3AM...SINCE WE DO
HAVE SOMEWHAT OF AN UPSLOPE COMPONENT. THE OTHER CONCERN WE HAVE
TONIGHT IS THE FOG POTENTIAL WHERE THE SNOWFALL TOOK PLACE LAST
NIGHT. SNOW/CLOUD DISCRIMINATOR PRODUCT FROM CIRA IS SHOWING THE
BULK OF THE SNOW OCCURRED IN THE NORTHERN PANHANDLE WHICH LOOKS
TO BE THE MOST FAVORABLE REGION FOR FOG DEVELOPING OVERNIGHT. THIS
AREA IS ALSO BEGIN TO CLEAR OUT WITH SOME PATCHY FOG BEGINNING TO
SHOW UP IN DAWES AND BOX BUTTE COUNTIES. HRRR ALSO SHOWS GOOD
INDICATIONS OF THIS FOG PERSISTING THROUGH THE NIGHT. WE MAY ALSO
HAVE TO WATCH THIS AREA FOR POTENTIAL FOG ADVISORY.
OTHERWISE...CURRENT FORECAST APPEARS TO BE ON TRACK.
UPDATE ISSUED AT 415 PM MDT THU MAY 8 2014
SENDING OUT A QUICK UPDATE TO INCREASE PRECIPITATION CHANCES
ACROSS ALBANY...LARAMIE AND KIMBALL COUNTIES AS A BATCH OF RAIN
AND EMBEDDED THUNDER MOVES EAST THROUGH THAT REGION. THE BULK OF
THE CONVECTION SHOULD END AFTER SUNSET.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 330 PM MDT THU MAY 8 2014
SNOW HAS COME TO AN END ACROSS THE NORTHERN NE PANHANDLE THIS AFTN
AS AN INTENSE SFC LOW AND ASSOCIATED MID LEVEL TROWAL HAVE EXITED THE
AREA TO THE NORTHEAST. ONLY CONCERN IN THE NEAR TERM WILL BE THE
POTENTIAL FOR CONVECTIVE ACTIVITY THROUGH THIS EVE. CLEARING SKIES ON THE
BACK SIDE OF THE SYSTEM HAVE ALLOWED TEMPS TO WARM NICELY...INTO THE
MIDDLE TO UPPER 40S ACROSS MUCH OF SOUTHEAST WY. MID LEVELS ARE QUITE
COLD WITH LAPS SOUNDINGS SHOWING H5 TEMPS TO -20C...SO A GREAT SETUP
FOR INSTABILITY RAIN SHOWERS. LATEST RADAR LOOP SHOWS THIS ACTIVITY
CONFINED TO THE I80 CORRIDOR...AND BELIEVE THIS TREND WILL CONTINUE
THROUGH THE EARLY EVE AS MESOSCALE MODELS SHOW LIFTED INDICES AROUND
ZERO HERE. WE HAVE SEEN SOME LIGHTNING STRIKES ALONG THE CO BORDER
IN THE PAST FEW HOURS...BUT MODEST CONVECTIVE INSTABILITY PROFILES
SUGGEST MOST OF THIS ACTIVITY WILL BE OF THE SHOWER VARIETY. LARGE
SCALE SUBSIDENCE WILL BUILD INTO THE AREA BY LATE EVE BENEATH WEAK
SHORTWAVE RIDGING...ENDING THE THREAT FOR SHOWERS AND STORMS. NEXT
CHANCE FOR CONVECTION WILL BE FRI AFTN AHEAD OF THE NEXT WEAK MID LEVEL
SHORTWAVE EMBEDDED WITHIN ZONAL FLOW ALOFT. WENT AHEAD AND ADDED ISO
THUNDER TO THE GRIDS AS THE LATEST GFS IS SHOWING 500 TO 750 J/KG OF
SBCAPE. NAM BUFKIT SOUNDINGS SHOW SOME WEAK ELEVATED INSTABILITY AS
WELL. NO CONCERNS FOR SEVERE WEATHER THOUGH. DESPITE SOME HIGH LEVEL
CLOUD COVER LIKELY MOVING OVERHEAD WITH INCREASING 700-300 MILLIBAR
MOISTURE...DOWNSLOPE WARMING SHOULD AID IN WIDESPREAD 60S FOR HIGHS
EAST OF THE LARAMIE RANGE. MOST OF THE SNOW IN THE PANHANDLE SHOULD
BE MELTED BY THEN...SO EXPECT A MINIMAL IMPACT TO TEMPS.
ATTENTION THEN SHIFTS TO THE POTENTIAL FOR YET ANOTHER MAJOR STORM
FOR THE WEEKEND. MODELS ARE IN GREAT AGREEMENT SHOWING A VIGOROUS
UPPER-LEVEL TROUGH DIGGING INTO THE GREAT BASIN ON SAT. MOIST SOUTH
WEST FLOW ALOFT AND A FEW DISTURBANCES EMANATING FROM THE PARENT
TROUGH SUGGESTS ANOTHER GOOD CHANCE FOR SHOWERS AND STORMS...THOUGH
WESTERLY LOW LEVEL FLOW SUGGESTS THE BULK OF THIS ACTIVITY WILL BE
ALONG AND WEST OF THE LARAMIE RANGE. LIMITED MOISTURE SHOULD KEEP
SEVERE WEATHER AT BAY THIS TIME AROUND...THOUGH SHEAR PROFILES
WILL BE RATHER STRONG. GFS...NAM...AND ECMWF ALL SHOW A STRONG SFC
COLD FRONT BLASTING SOUTH ACROSS THE CWA LATE SAT NIGHT. NORTH TO
NORTH EAST SFC UPSLOPE FLOW AND LARGE SCALE VERTICAL ASCENT WILL
ALMOST CERTAINLY FAVOR PCPN DEVELOPMENT...BUT THE BIG QUESTION NOW
IS EXACTLY WHERE. THE GFS IS STILL THE OUTLIER WITH HEAVY PCPN
BANDING FROM NORTH CENTRAL CO INTO THE SOUTHERN PANHANDLE...WHILE
THE ECMWF AND GEM ARE MUCH FURTHER NORTH WITH THE FRONTOGENESIS
BAND AND WOULD AFFECT A LARGER PART OF OUR CWA. REGARDLESS...H7
TEMPS FALL TO BETWEEN -8C AND -12C IN THE POST FROPA AIR MASS WITH
1000-500 MB THICKNESSES RANGING FROM 540 TO 549 DM FROM NORTHWEST
TO SOUTHEAST AT 12Z SUN. THIS WOULD SUPPORT SNOW... AND A LOT OF
IT IF MODELED QPF VALUES ARE ANYTHING CLOSE TO WHAT ACTUALLY
TRANSPIRES. IT IS A LITTLE UNSETTLING THAT THE ECMWF HAS BEEN
CONSISTENT OVER THE LAST COUPLE OF RUNS WITH THE PLACEMENT OF THE
HEAVIEST SNOW. IT WAS ALSO THE FIRST TO LOCK ON TO THIS PARTICULAR
STORM EVOLUTION. IT IS MUCH TOO EARLY FOR ANY SORT OF
HEADLINE...BUT CONFIDENCE IS HIGH THAT A PORTION OF OUR CWA WILL
SEE SIGNIFICANT WINTER WEATHER. WENT AHEAD AND ISSUED A SPECIAL
WEATHER STATEMENT HIGHLIGHTING THE POTENTIAL STORM FOR PUBLIC
AWARENESS.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 330 PM MDT THU MAY 8 2014
FORECAST CHALLENGES EARLY IN THE EXTENDED PERIOD WILL FOCUS ON THE
SPRING STORM SYSTEM MOVING ACROSS THE CENTRAL ROCKIES AND PLAINS.
THERE ARE TIMING...STRENGTH AND POSITION DIFFERENCES WITH EMERGENCE
OF THE UPPER LOW FROM THE CENTRAL GREAT BASIN SUNDAY. THE GFS IS
TRENDING SLIGHTLY FASTER AND NORTH OF THE ECMWF. AT 12Z SUNDAY...GFS
PROGS THE 554DM LOW OVER EAST CENTRAL UT...WHILE THE ECMWF/S 550DM
LOW IS SITUATED IN SOUTHWEST UT. THE PRIMARY SURFACE LOW SHOWN BY
THE GFS AT THE SAME TIME IS OVER FAR SOUTHWEST CO AND THE ECMWF/S
LOW IS ALONG THE AZ/UT BORDER. BY 00Z MONDAY...GFS 559DM LOW IS
OVER FAR WESTERN CO AND THE ECWMF 554DM LOW IS OVER SOUTH CENTRAL
UT. THE SURFACE LOW REDEVELOPS AND INTENSIFIES OVER THE NORTHERN
TX PANHANDLE IN THE GFS...AND SOUTHWEST CORNER OF KS IN THE ECMWF.
THE 1000-500MB THICKNESS GRADIENT RAPIDLY TIGHTENS AND INTENSE
LOW/MID LEVEL ASCENT DEVELOPS. COLD AIR AT LOW LEVELS WILL BE
ADVECTED SOUTH INTO THE STORM SYSTEM ALONG THE EASTERN SLOPES OF
THE ROCKIES...LOWERING SNOW LEVELS SIGNIFICANTLY. PLENTY OF
MOISTURE WRAPPING INTO THE LOW...MID LEVEL QG FORCING AND LOW
LEVEL UPSLOPE WILL RESULT IN SIGNIFICANT PRECIPITATION....WITH
SNOW LEVELS POSSIBLY DROPPING AS LOW AS 4500 FT. A CONSENSUS OF
THE GFS AND ECMWF QPF FROM 00Z SUNDAY THROUGH 12Z MONDAY INDICATES
BETWEEN 1.5 AND 2.5 INCHES OF LIQUID PRECIPITATION. CONSENSUS MODEL
SNOW ACCUMULATIONS PROJECT BETWEEN 12 AND 20 INCHES FOR THE MOUNTAINS...
4 TO 10 INCHES LOWER ELEVATIONS ALONG AND SOUTH OF I-80...AND 1 TO 4
INCHES NORTH OF I-80. STILL PLENTY OF UNCERTAINTY WITH THIS STORM
AND WILL CONTINUE TO EVALUATE TRENDS AS THE STRENGTH AND TRACK OF
THE STORM SYSTEM CAN CHANGE FROM ONE MODEL RUN TO THE NEXT.
IT WILL BE MUCH COLDER SUNDAY AS 700MB TEMPERATURES FALL TO -5C TO
-10C. HIGH TEMPERATURES SUNDAY WILL RANGE FROM THE 20S MOUNTAINS TO
THE 40S OVER THE PLAINS. THESE TEMPERATURES MAY BE NEED TO BE LOWERED
WITH LATER FORECASTS. GUSTY NORTHEAST WINDS OF 20 TO 30 MPH WILL ADD
TO THE CHILL.
IF YOU BELIEVE THE GFS...SNOW WILL BEGIN TO TAPER OFF FROM WEST
TO EAST MONDAY MORNING. THE ECMWF KEEPS THE UPPER TROUGH AXIS ALONG
THE FRONT RANGE WHICH WOULD PROLONG THE PRECIPITATION INTO MONDAY
NIGHT. NORTHWEST FLOW ALOFT WILL PREVAIL TUESDAY THROUGH THURSDAY.
THERE ARE INDICATIONS THAT IT WILL NOT BE DRY STABLE FLOW AS THERE
WILL BE SOME MINOR DISTURBANCES WHICH MAY GENERATE SHOWERY EPISODES.
TEMPERATURES MODERATE TOWARD SEASONAL NORMALS BY THE END OF THE PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY EVENING)
ISSUED AT 1115 PM MDT THU MAY 8 2014
MAINLY VFR ACROSS THE AREA TONIGHT BUT SOME LOCAL LOW CLOUDS AND
FOG WILL PRODUCE IFR. AFTER SUNRISE FOG AND LOW CLOUDS WILL
DISSIPATE. WINDS WILL MAINLY BE ON THE LIGHT SIDE TONIGHT THROUGH
FRIDAY. SCATTERED SHOWERS AND ISOLATED WEAK THUNDERSTORMS WEST OF
THE LARAMIE RANGE FRIDAY AFTERNOON WITH ISOLATED SHOWERS AND
THUNDERSTORMS TO THE EAST OF THE LARAMIE RANGE.
&&
.FIRE WEATHER...
ISSUED AT 300 PM MDT THU MAY 8 2014
NO FIRE WEATHER CONCERNS. MILD CONDITIONS ARE EXPECTED FOR FRIDAY
AND SATURDAY...BUT WINDS AND RELATIVE HUMIDITY VALUES ARE EXPECTED
TO REMAIN WELL OUTSIDE OF CRITICAL THRESHOLDS. ANOTHER SPRING STORM
WILL AFFECT THE AREA SUNDAY AND MONDAY...BRINGING COOLER TEMPERATURES
AND WIDESPREAD RAIN AND SNOW.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...REC
SHORT TERM...HAMMER
LONG TERM...JAMSKI
AVIATION...SML
FIRE WEATHER...HAMMER
AREA FORECAST DISCUSSION
NWS TAUNTON MA
346 AM EDT SUN MAY 11 2014
.SYNOPSIS...
A COLD FRONT WILL CROSS OUR REGION EARLY THIS MORNING...BRINGING
MORE SCATTERED SHOWERS. HIGH PRESSURE BUILDS IN LATER TODAY.
SCATTERED SHOWERS...AND A THUNDERSTORM OR TWO...ARE POSSIBLE
MONDAY AFTERNOON AS ANOTHER WARM FRONT APPROACHES. BACK DOOR COLD
FRONT WILL SWING THROUGH ON TUESDAY ALLOWING FOR HIGH PRESSURE ON
WEDNESDAY AND BELOW AVERAGE TEMPS. SEASONABLE TEMPERATURES AND
UNSETTLED WEATHER ARE ANTICIPATED THURSDAY THROUGH SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A COLD FRONT WAS LOCATED ACROSS RI AND EASTERN MA...AND CONTINUING
TO MARCH OFFSHORE. DEW POINTS WILL TAKE A LITTLE LONGER TO DROP
OFF THOUGH...WITH THE LEADING EDGE OF LOW-LEVEL DRY AIR JUST
MOVING INTO CENTRAL SOUTHERN NEW ENGLAND.
REGIONAL RADARS SHOWING ANOTHER AREA OF SHOWERS MOVING ACROSS
SOUTHERN NEW ENGLAND. LATEST RUNS OF THE HRRR AND RAP MODELS ARE
HANDLING THIS AREA WELL...SO WILL USE THEM TO ADJUST THE TIMING OF
RAINFALL THIS MORNING. LATEST MESOANALYSIS SHOWS A DEARTH OF
INSTABILITY...SO THINKING THUNDERSTORMS ARE NOT VERY LIKELY. SOME
HIGHER REFLECTIVITY ALONG THE SOUTH COAST...SO WILL CONTINUE TO
MONITOR POTENTIAL FOR THUNDERSTORMS.
ONCE THIS COLD FRONT MOVES OFFSHORE BY MID MORNING...EXPECTING
BEAUTIFUL WEATHER FOR THE REST OF MOTHERS DAY. HIGH PRESSURE
ARRIVES DURING THE DAY. PLENTY OF SUNSHINE TODAY...BUT
TEMPERATURES WILL LIKELY NOT BE AS HIGH AS SATURDAY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
TONIGHT...EXPECT HIGH PRESSURE TO SHIFT EAST. WILL SEE MOSTLY
CLEAR SKIES EARLY...THEN SOME HIGH CLOUDS WILL START TO MOVE IN
FROM THE WEST AFTER MIDNIGHT. LIGHT WEST WINDS WILL BE IN PLACE...
SO EXPECT TEMPS TO ONLY FALL BACK TO THE MID 40S TO LOWER
50S...POSSIBLY THE MID 50S IN THE URBAN CENTERS.
MONDAY...A HIGH PRESSURE TO OUR SOUTH AND PLENTY OF SUNSHINE TO
START THE DAY WILL LEAD TO MAXIMUM TEMPERATURES AROUND 80 DEGREES.
MODEL SOUNDINGS DEPICT WEAK INSTABILITY...SO THINKING SHOWERS
WOULD BE MORE LIKELY THAN THUNDERSTORMS. THIS COULD CHANGE IF DEW
POINTS GET HIGHER THAN CURRENTLY FORECAST. THE MOST LIKELY PERIOD
FOR SHOWERS WILL BE DURING THE AFTERNOON HOURS.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
HIGHLIGHTS...
* BACK DOOR COLD FRONT ON TUESDAY
* HIGH PRESSURE ON WEDNESDAY
* SEASONABLE TEMPS AND UNSETTLED WEATHER THURSDAY THROUGH THE WEEKEND
MODELS AND CONFIDENCE...
LATEST 00Z GUIDANCE IS IN AGREEMENT SHOWING A STRONG WEST COAST
RIDGE WHICH WILL SUPPORT A BROAD/DEEP TROUGH SETTLING OVER THE ERN
HALF OF THE CONUS. CLOSER AT HOME...A BACK DOOR COLD FRONT WILL
SWING THROUGH THE REGION ON TUESDAY FOLLOWED BY HIGH PRESSURE
BUILDING IN THE GULF OF MAINE. AS THE TROUGH MOVES TOWARDS NEW
ENGLAND...A NORTH ATLANTIC RIDGE WILL HOLD STEADY...AND EVENTUALLY
BLOCKS THE PROGRESSION OF THE TROUGH RESULTING IN POSSIBLE CUT-
OFF LOW NEAR THE GREAT LAKES BY FRIDAY. A LOT OF TIMING ISSUES
WITH THIS FORECAST BUT CONFIDENCE IS INCREASING THAT ASIDE FROM
HIT OR MISS IN THE MEDIUM RANGE...THE LONG TERM WILL BE UNSETTLED
AND SEASONABLE. SOLUTION SPREAD IS GRADUALLY NARROWING BUT
GFS/GEFS ARE CONTINUING TO BRING LEADING HGT FALLS INTO THE EAST
FASTER THAN MOST OTHER GUIDANCE IN THE MID-LATE WEEK TIME FRAME.
TRENDS AND CONTINUITY OVER MULTIPLE DAYS HAVE BEEN FAVORING SLOWER
TIMING AS SUPPORTED BY THE AMPLIFIED NATURE OF THE APPROACHING
TROUGH. THEREFORE TRENDED THIS FORECAST TOWARDS THE EC ENSEMBLES
AS WELL AS WPC.
DETAILS...
TUESDAY INTO WEDNESDAY...
GUIDANCE IS ON COURSE FOR A BACK DOOR COLD FRONT TO MOVE ACROSS
THE REGION ON TUESDAY AS HIGH PRESSURE IN THE GULF OF MAINE
BUILDS. FRONT WILL PUSH THROUGH TUESDAY MORNING ALLOWING FOR COOL
MARITIME AIR TO FILTER INTO SOUTHERN NEW ENGLAND. BREAKS IN THE
CLOUD COVER MAY ALLOW FOR THE WESTERN HALF TO WARM IN THE
60S...BUT CLOSER TO THE COASTLINE WILL STRUGGLE TO GET OUT OF THE
50S. THIS EASTERLY FLOW OFF THE WATERS WILL FEEL VERY CHILLY
COMPARED TO THE 70-80F THE REGION HAS EXPERIENCED THIS WEEKEND.
BECAUSE OF THE ONSHORE FLOW...CANT RULE OUT FOG/DRIZZLE AND LOW
CLOUDS ESP ACROSS EASTERN COASTLINES.
HIGH PRESSURE WILL BUILD IN ACROSS THE GULF OF MAINE KEEPING MOST OF
THE REGION DRY AND TEMPS SEASONABLE ON WEDNESDAY. HOWEVER STALLED
BOUNDARY ACROSS CENTRAL NY MAY ALLOW FOR SOME ISO SHOWERS ACROSS
WESTERN ZONES. ONCE AGAIN COOLER TEMPS ON WED DUE TO ONSHORE FLOW.
THURSDAY AND BEYOND...
STRONG HIGH PRESSURE TO THE EAST HAS SLOWED THE PROGRESSION OF
THE DIGGING TROUGH AND STALLS IT JUST WEST OF THE REGION. HOWEVER
BY THURSDAY...HIGH PRESSURE WILL MOVE OUT TO SEA ALLOWING FOR THE
TROUGH TO MAKE ITS WAY TOWARDS THE NORTHEAST. EXPECT SEVERAL WEAK
WAVES TO DEVELOP AHEAD OF THIS TROUGH WHICH WILL APPROACH THE AREA
DURING THURSDAY INTO FRIDAY. ALTHOUGH EXACT TIMING OF EACH WAVE
IS STILL UNCERTAIN...IT APPEARS THAT THE BEST CHANCE FOR HIGHER
PRECIP LOOKS TO BE FRIDAY AS LOW PRESSURE SYSTEM DEVELOPS ALONG
THE FRONT. STRONG LLJ AND INCREASING MOISTURE TRANSPORT SUPPORTS
THE IDEA OF THE POSSIBILITY OF HEAVY RAINFALL. ESPECIALLY SINCE
THE TROUGH IS TAPPING INTO DEEP GULF MOISTURE AS WELL AS A
POSSIBLE SURFACE LOW MOVING UP FROM THE BAHAMAS. BECAUSE OF THE
UNCERTAINTY ON EXACT TIMING...CONTINUED TO MENTION CHANCE POPS
FOR THURSDAY AND FRIDAY. HELD OFF ON LIKELY POP FOR FRIDAY BECAUSE
OF THE LOW CONFIDENCE ON THE EXACT TIMING...BUT WOULD NOT BE
SURPRISED IF NEXT SHIFT INCREASES POPS.
MODELS DIFFER ON THE TIMING ON THE EXIT OF THE SYSTEM ON
SATURDAY...IN FACT SOME MODELS WANT TO DRY SLOT SOUTHERN NEW
ENGLAND. HAVE LOW CONFIDENCE IN THIS OCCURRING AS A SLIGHT CHANGE IN
THE PATH COULD LEAD TO A WET WEEKEND. OVERALL IT APPEARS THAT THE
STRONG ATLANTIC RIDGE WILL STALL THE SYSTEM JUST EAST OF THE
REGION ON SATURDAY AND INTO SUNDAY. THEREFORE CONTINUED TO
MENTION A SLIGHT CHANCE OF PRECIP.
A SEASONABLE BUT HUMID AIR MASS WILL OVERSPREAD THE REGION WITH SW
FLOW TAPPING INTO THE GULF...ADVECTING HIGHER DEWPOINTS AHEAD OF
THE TROUGH. FOG IS A POSSIBILITY ON THURSDAY AND ON FRIDAY. HIGHS
WILL GENERALLY TOP OFF IN THE UPPER 60S TO LOW 70S WITH COOLER
CONDITIONS ALONG THE COAST...ESP THE SOUTH COAST DUE TO SOUTHERLY
FLOW.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH MONDAY/...
THROUGH 12Z...HIGH CONFIDENCE. VFR WITH SCATTERED MVFR IN SHOWERS.
TODAY...HIGH CONFIDENCE. VFR CONDITIONS PREVAIL. WEST WIND GUSTS
UP TO 20 KT POSSIBLE.
TONIGHT...HIGH CONFIDENCE. VFR.
MONDAY...HIGH CONFIDENCE VFR CONDITIONS TO START. IF SHOWERS
START TO POP DURING THE AFTERNOON...CIGS SHOULD DROP AND VSBY MAY
DROP...TO MVFR OR LOCALIZED BRIEF IFR CONDITIONS.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.
OUTLOOK...MONDAY NIGHT THROUGH THURSDAY...
MONDAY NIGHT...MODERATE CONFIDENCE. VFR WITH MVFR CONDITIONS IN SCT
SHOWERS/TSTORMS.
TUESDAY INTO WEDNESDAY...MODERATE CONFIDENCE. BACK DOOR COLD
FRONT WILL MOVE THROUGH SWITCHING THE WESTERLY WINDS TO THE EAST
ALLOWING FOR FOG AND DRIZZLE TO ROLL IN. MVFR CONDITIONS WILL
POSSIBLE IFR. CONDITIONS IMPROVING ON WEDNESDAY TO VFR.
THURSDAY...LOW CONFIDENCE. STAGNANT COLD FRONT SLOWLY MOVES EAST
WITH A CHANCE OF A WEAK SHOWER ESP ACROSS WESTERN SITES. WINDS
WILL SWITCH TO THE SOUTHEAST. OVERCAST SKIES WITH VFR/MVFR CIGS.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH MONDAY/...MODERATE CONFIDENCE.
TODAY AND TONIGHT...HIGH PRESSURE BUILDS ACROSS THE WATERS.
EXPECT W WINDS 15 KT OR LESS. GUSTS MAY APPROACH 20 KT ON
NEARSHORE WATERS THIS AFTERNOON. SEAS SHOULD REMAIN BELOW 5 FT.
MONDAY...INCREASING SOUTHWEST WINDS WILL SLOWLY BUILD SEAS ACROSS
THE OUTER COASTAL WATERS...BUT STILL EXPECTING CONDITIONS TO
REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA.
OUTLOOK...MONDAY NIGHT THROUGH THURSDAY...
MODERATE CONFIDENCE THROUGH PERIOD.
MONDAY NIGHT-TUESDAY...A WARM FRONT WILL APPROACH THE WATERS FROM
THE SOUTH ALLOWING FOR SCATTERED SHOWERS AND POSSIBLE
THUNDERSTORMS. BEST LOCATIONS WILL BE IN THE SOUTHERN AND WESTERN
MOST WATERS.
TUESDAY INTO WEDNESDAY...WESTERLY WINDS WILL SHIFT TO THE EAST ON
TUESDAY AS BACK DOOR COLD FRONT MOVES ACROSS THE WATERS. FOG AND
DRIZZLE POSSIBLE AND EASTERLY SWELL INCREASES SEAS. HIGH PRESSURE
WILL BUILD OVER THE EASTERN WATERS ON WEDNESDAY. SCA MAY BE NEEDED
FOR THE PERIOD.
THURSDAY...LOW CONFIDENCE...STATIONARY FRONT WILL SLOWLY MOVE EAST
WITH A CHANCE OF A WEAK SHOWER. SEAS REMAIN AT 5 FT SO SCA MAY
CONTINUE TO BE NEEDED. SE WINDS AHEAD OF THE FRONT REMAIN BELOW
25KTS TO START BUT MAY INCREASE LATE IN THE PERIOD.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EDT THIS MORNING FOR ANZ254-
256.
SMALL CRAFT ADVISORY UNTIL 10 AM EDT THIS MORNING FOR ANZ255.
&&
$$
SYNOPSIS...BELK/DUNTEN
NEAR TERM...BELK
SHORT TERM...BELK
LONG TERM...DUNTEN
AVIATION...BELK/DUNTEN
MARINE...BELK/DUNTEN
AREA FORECAST DISCUSSION
NWS TAUNTON MA
322 AM EDT SUN MAY 11 2014
.SYNOPSIS...
A COLD FRONT WILL CROSS OUR REGION EARLY THIS MORNING...BRINGING
MORE SCATTERED SHOWERS. HIGH PRESSURE BUILDS IN LATER TODAY.
SCATTERED SHOWERS...AND A THUNDERSTORM OR TWO...ARE POSSIBLE
MONDAY AFTERNOON AS ANOTHER WARM FRONT APPROACHES. A BACK DOOR
COLD FRONT WILL MOVE WEST ACROSS THE REGION TUESDAY...ALLOWING
FOR HIGH PRESSURE ON WEDNESDAY. SEASONABLE TEMPERATURES AND
UNSETTLED WEATHER ARE FORECAST FOR THE END OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
A COLD FRONT WAS LOCATED ACROSS RI AND EASTERN MA...AND CONTINUING
TO MARCH OFFSHORE. DEW POINTS WILL TAKE A LITTLE LONGER TO DROP
OFF THOUGH...WITH THE LEADING EDGE OF LOW-LEVEL DRY AIR JUST
MOVING INTO CENTRAL SOUTHERN NEW ENGLAND.
REGIONAL RADARS SHOWING ANOTHER AREA OF SHOWERS MOVING ACROSS
SOUTHERN NEW ENGLAND. LATEST RUNS OF THE HRRR AND RAP MODELS ARE
HANDLING THIS AREA WELL...SO WILL USE THEM TO ADJUST THE TIMING OF
RAINFALL THIS MORNING. LATEST MESOANALYSIS SHOWS A DEARTH OF
INSTABILITY...SO THINKING THUNDERSTORMS ARE NOT VERY LIKELY. SOME
HIGHER REFLECTIVITY ALONG THE SOUTH COAST...SO WILL CONTINUE TO
MONITOR POTENTIAL FOR THUNDERSTORMS.
ONCE THIS COLD FRONT MOVES OFFSHORE BY MID MORNING...EXPECTING
BEAUTIFUL WEATHER FOR THE REST OF MOTHERS DAY. HIGH PRESSURE
ARRIVES DURING THE DAY. PLENTY OF SUNSHINE TODAY...BUT
TEMPERATURES WILL LIKELY NOT BE AS HIGH AS SATURDAY.
&&
.SHORT TERM /TONIGHT THROUGH 6 PM MONDAY/...
TONIGHT...EXPECT HIGH PRESSURE TO SHIFT EAST. WILL SEE MOSTLY
CLEAR SKIES EARLY...THEN SOME HIGH CLOUDS WILL START TO MOVE IN
FROM THE WEST AFTER MIDNIGHT. LIGHT WEST WINDS WILL BE IN PLACE...
SO EXPECT TEMPS TO ONLY FALL BACK TO THE MID 40S TO LOWER
50S...POSSIBLY THE MID 50S IN THE URBAN CENTERS.
MONDAY...A HIGH PRESSURE TO OUR SOUTH AND PLENTY OF SUNSHINE TO
START THE DAY WILL LEAD TO MAXIMUM TEMPERATURES AROUND 80 DEGREES.
MODEL SOUNDINGS DEPICT WEAK INSTABILITY...SO THINKING SHOWERS
WOULD BE MORE LIKELY THAN THUNDERSTORMS. THIS COULD CHANGE IF DEW
POINTS GET HIGHER THAN CURRENTLY FORECAST. THE MOST LIKELY PERIOD
FOR SHOWERS WILL BE DURING THE AFTERNOON HOURS.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
HEADLINES...
* ABOVE AVERAGE TEMPS ON MONDAY
* BACK DOOR COLD FRONT ON TUESDAY AND WEDNESDAY
* UNSETTLED WEATHER THURSDAY THROUGH THE WEEKEND
OVERVIEW...
FLOW INCREASINGLY BECOME MORE WAVY OVER THE UNITED STATES AS
SHORTWAVE DIVES SOUTH ALONG A TROUGH IN THE WESTERN UNITED STATES
WHILE A RIDGE BUILDS IN THE EAST. NORMALLY THE BUILDING RIDGE
MEANS PLEASANT WEATHER...BUT THIS TIME A HIGH PRESSURE SYSTEM IN
EASTERN CANADA HAS A SAY IN WHAT HAPPENS AS A LOBE OF THE HIGH
PRESSURE SYSTEM DROPS DOWN THE EAST COAST AND ALLOWS A COOLER
OCEAN AIR MASS TO FLOW INTO THE NORTHEAST ALONG A BACKDOOR COLD
FRONT. TIMING ISSUES IN MODELS AS TO WHEN THE LOBE DOES DROP DOWN
INTO THE REGION IS READILY SEEN. HAVE STAYED WITH ENSEMBLE AND WPC
GUIDANCE IN THIS FORECAST AS FAR AS TIMING AND SENSIBLE WEATHER
GOES FOR THIS PERIOD OF RATHER DIVERGENT MODEL SOLUTIONS.
DAILIES...
MONDAY NIGHT...A WARM FRONT ASSOCIATED WITH A LOW PRESSURE SYSTEM
OVER THE NORTHERN MIDWEST APPROACHES THE REGION AROUND EARLY NIGHT
HOURS WITH SHOWERS POSSIBLE ESPECIALLY IN WESTERN SECTIONS OF MA
AND CT.
TUESDAY AND WEDNESDAY...WITH THE LOBE OF HIGH PRESSURE BEGINNING TO
WORK ITS WAY SOUTH AND WEST FROM SOUTHEASTERN CANADA...NORTHEASTERN
ONSHORE FLOW SHOULD WORK ITS WAY INTO THE REGION ESPECIALLY BY THE
AFTERNOON HOURS. A NOTICEABLE TEMPERATURE DIFFERENCE BETWEEN MONDAY
AND TUESDAY SHOULD BE SEEN AS THE ONSHORE FLOW WILL BE BRINGING AN
AIR MASS CLOSE TO WHAT THE SEA SURFACE TEMPERATURES IN THE GULF OF
MAINE WHERE TEMPS ARE ONLY AROUND THE UPPER 40S TO LOW 50S. DIURNAL
HEATING SHOULD INCREASE TEMPERATURES FROM THERE...BUT MAX TEMPS MAY
NOT REACH 60 ON THE EASTERN SIDE OF THE FRONT. WITH ONSHORE
FLOW...CAN/T RULE OUT DRIZZLE/SHOWERS.
THURSDAY THROUGH THE WEEKEND...MAJOR DISCREPANCY IN THIS PERIOD AS
TO THE EXACT SENSIBLE WEATHER WITH THE TROUGH FROM THE WEST MOVING
IN. AN UPPER LEVEL LOW PRESSURE SYSTEM SHOULD FORM FROM THAT WITH
THE ABILITY TO DRAW MOISTURE IN FROM THE GULF AND A LOW FROM THE
TROPICS. A COLD FRONT HAS BEEN STALLED OUT OVER THE EASTERN SEA
BOARD SINCE TUESDAY AND THIS WILL HAVE WAVES RIDING NORTH OF IT
DURING THIS PERIOD. HAVE STAYED WITH WPC AND ENSEMBLES DURING THIS
PERIOD FOR SENSIBLE HIGHLIGHTS WITH THE HIGH AMOUNT OF SPREAD IN THE
DETERMINISTIC MODELS. FRIDAY AND SATURDAY HAVE THE BEST CHANCE FOR
ORGANIZED PRECIPITATION WITH THE UPPER LEVEL LOW MOVING TOWARD THE
REGION. TEMPS SHOULD REMAIN SEASONABLE DURING THIS TIME PERIOD AND
DEW POINTS SHOULD KEEP THIS PERIOD RATHER HUMID.
&&
.AVIATION /07Z SUNDAY THROUGH THURSDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH MONDAY/...
THROUGH 12Z...HIGH CONFIDENCE. VFR WITH SCATTERED MVFR IN SHOWERS.
TODAY...HIGH CONFIDENCE. VFR CONDITIONS PREVAIL. WEST WIND GUSTS
UP TO 20 KT POSSIBLE.
TONIGHT...HIGH CONFIDENCE. VFR.
MONDAY...HIGH CONFIDENCE VFR CONDITIONS TO START. IF SHOWERS
START TO POP DURING THE AFTERNOON...CIGS SHOULD DROP AND VSBY MAY
DROP...TO MVFR OR LOCALIZED BRIEF IFR CONDITIONS.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF.
KBDL TERMINAL...HIGH CONFIDENCE IN TAF.
OUTLOOK...MONDAY NIGHT THROUGH THURSDAY...
MONDAY NIGHT...MODERATE CONFIDENCE. AS WARM FRONT MOVES IN...MAY
SEE MVFR CONDITIONS.
TUESDAY INTO WEDNESDAY...MODERATE CONFIDENCE. AS BACKDOOR COLD
FRONT MOVES THROUGH...WEST WINDS CHANGE TO NORTHEAST WINDS. COULD
SEE DRIZZLE AND FOG DURING THIS PERIOD AS WELL. MVFR CONDITIONS TO
START WILL CHANGE TO IFR FROM EAST TO WEST ALONG THE FRONT.
THURSDAY...LOW CONFIDENCE...STAGNANT COLD FRONT SLOWLY MOVES EAST
WITH A CHANCE OF A WEAK SHOWER. SE WINDS AHEAD OF THE FRONT REMAIN
BELOW THRESHOLDS. OVERCAST SKIES ALLOW FOR MVFR CONDITIONS.
&&
.MARINE...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT.
MODERATE...30 TO 60 PERCENT.
HIGH...GREATER THAN 60 PERCENT.
SHORT TERM /THROUGH MONDAY/...MODERATE CONFIDENCE.
TODAY AND TONIGHT...HIGH PRESSURE BUILDS ACROSS THE WATERS.
EXPECT W WINDS 15 KT OR LESS. GUSTS MAY APPROACH 20 KT ON
NEARSHORE WATERS THIS AFTERNOON. SEAS SHOULD REMAIN BELOW 5 FT.
MONDAY...INCREASING SOUTHWEST WINDS WILL SLOWLY BUILD SEAS ACROSS
THE OUTER COASTAL WATERS...BUT STILL EXPECTING CONDITIONS TO
REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA.
OUTLOOK...MONDAY NIGHT THROUGH THURSDAY...
MODERATE CONFIDENCE THROUGH PERIOD.
MONDAY NIGHT-TUESDAY...AS WARM FRONT APPROACHES THE REGION...
SCATTERED SHOWERS AND POSSIBLE THUNDERSTORMS SHOULD BE SEEN
ESPECIALLY IN SOUTHERN AND WESTERN MOST WATERS.
TUESDAY INTO WEDNESDAY...NORTHEAST WINDS OVERTAKE WEST WINDS FROM
EAST TO WEST AS BACKDOOR FRONT PUSHES THROUGH WITH COLDER AIR. FOG
AND DRIZZLE IS POSSIBLE IN ONSHORE FLOW WITH POSSIBLE SWELL IN SEAS
THAT HAVE 5FT WAVES. SCA MAY BE NEEDED FOR THE PERIOD.
THURSDAY...LOW CONFIDENCE...STAGNANT COLD FRONT SLOWLY MOVES EAST
WITH A CHANCE OF A WEAK SHOWER. SEAS REMAIN AT 5 FT SO SCA MAY
CONTINUE TO BE NEEDED. SE WINDS AHEAD OF THE FRONT REMAIN BELOW
25KTS TO START BUT MAY INCREASE LATE IN THE PERIOD.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
MA...NONE.
NH...NONE.
RI...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EDT THIS MORNING FOR ANZ254-
256.
SMALL CRAFT ADVISORY UNTIL 10 AM EDT THIS MORNING FOR ANZ255.
&&
$$
SYNOPSIS...BELK/NMB/99
NEAR TERM...BELK
SHORT TERM...BELK
LONG TERM...NMB/99
AVIATION...BELK/NMB/99
MARINE...BELK/NMB/99
AREA FORECAST DISCUSSION
NWS NEW YORK NY
133 AM EDT SUN MAY 11 2014
.SYNOPSIS...
A COLD FRONT WILL MOVE ACROSS LATE TONIGHT. HIGH PRESSURE THEN
BUILDS OVER THE AREA ON SUNDAY AND SUNDAY NIGHT. HIGH PRESSURE
DEPARTS ON MONDAY...AND THEN A SERIES OF FRONTAL BOUNDARIES AND
WEAK LOW PRESSURE SYSTEMS WILL MOVE ACROSS THE REGION THROUGH THE
MIDDLE OF THE WEEK. A STRONGER COLD FRONT IMPACTS THE REGION LATE
NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
05Z OBS INDICATED THAT COLD FRONT WAS JUST NW OF THE FORECAST
AREA. FINAL PUSH OF ORGANIZED PCPN ASSOCIATED WITH SHORTWAVE IS
CROSSING THE AREA OUT AHEAD OF THE COLD FRONT. SCT ACTIVITY RIGHT
ALONG THE BOUNDARY IS ALSO DEVELOPING FROM EASTERN PA THROUGH WRN
MA. WILL KEEP ISO THUNDER IN FORECAST FOR A FEW MORE HOURS...BUT
THREAT IS MINIMAL. HRRR HAS BEEN CONSISTENT IN PUSHING PCPN
THROUGH BETWEEN 03-07Z...LINGERING OVER FAR EASTERN LI AND SE CT
UNTIL 09Z...WHEN THE FRONT FINALLY CLEARS THE AREA. HAVE ADJUSTED
POPS TO ACCOUNT FOR THIS. NOT ANTICIPATING ANY FURTHER SEVERE
THREATS NOR FLOODING ISSUES.
ALSO...WITH RATHER LIGHT WESTERLY FLOW BEHIND THE FRONT...STILL THINKING
LOW LEVELS WILL BE SLOWER TO DRY OUT LATE TONIGHT.
THEREFORE...CONTINUE TO HAVE PATCHY FOG DEVELOPING LATE. LOWS
WERE A BLEND OF NAM12 AND MET GUIDANCE...HIGHER SIDE OF GUIDANCE.
TEMPS AND DEW PTS GENERALLY ON TRACK AS OF LATE THIS EVENING.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM MONDAY/...
BEHIND THE COLD FRONT...MID LEVEL RIDGING WITH HIGH PRESSURE
BUILDING IN AT THE SURFACE FROM THE SOUTH AND WEST WILL PROMOTE
DRY WEATHER DURING THIS PERIOD. WITH THE WESTERLY FLOW
SUNDAY...EXPECTING A QUICK INCREASE TO TEMPERATURES IN THE MORNING
WITH HIGHS WELL ABOVE NORMAL ONCE AGAIN...IN THE MID 70S TO LOWER
80S RANGE FOR MOST PLACES. THE JET STREAM ALOFT WILL BE LIFTING
FARTHER NORTH OF THE REGION WITH THE RIDGING. HIGHS WERE TAKEN
FROM MAVS AND INCREASED TWO DEGREES. SKIES WILL BE CLEARING SUNDAY
AND THESE MOSTLY CLEAR SKIES LINGER INTO SUNDAY NIGHT. LOWS SUNDAY
NIGHT WILL BE COOLER THAN OF RECENT NIGHTS WITH RADIATIONAL
COOLING AS WINDS WILL BE LIGHT. LOWS SUNDAY NIGHT WERE TAKEN FROM
ECS AND CONVEY A RANGE FROM THE MID 40S ACROSS RURAL AND INTERIOR
LOCATIONS TO THE LOWER 60S NEAR NYC.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
HIGH PRES DEPARTS ON MONDAY AS A DEEP UPPER TROUGH DIGS INTO THE
CENTRAL U.S. THIS TROUGH WILL EXTEND FROM CANADA INTO THE GULF OF
MEXICO...AND SFC LOW PRES WILL DEVELOP OVER THE WESTERN GREAT LAKES
BEFORE TRACKING TO THE NORTHEAST INTO CANADA. MEANWHILE...A WARM
FRONT APPROACHES ON MONDAY...AND THEN WEAK LOW PRES FORMS ALONG THE
BOUNDARY AS IT LIFTS TO THE NORTH. THAT BOUNDARY WILL BECOME NEARLY
STATIONARY NORTH OF THE REGION ON TUESDAY. AS A RESULT...WILL EXPECT
SCATTERED SHOWERS AND TSTMS TO DEVELOP MONDAY AFTERNOON...MAINLY
ACROSS NORTHERN ZONES. UNSETTLED WEATHER CONTINUES INTO TUESDAY AS
HIGH PRES OVER EASTERN CANADA DROPS SOUTH INTO THE GOLF OF MAINE.
THE STATIONARY FRONT NORTH OF THE AREA WILL PUSH TO THE SOUTH AS A
BACK DOOR COLD FRONT...AND THEN THE HIGH ANCHORS ITSELF OVER THE
WESTERN ATLANTIC THROUGH THE END OF THE WEEK.
THE UPPER TROUGH OVER THE MIDWEST WILL SLOWLY TRACK EAST...BUT WILL
EFFECTIVELY BECOME BLOCKED BY THE OFFSHORE HIGH. SEVERAL WEAK
IMPULSES WILL DEVELOP AT THE BASE OF THE TROUGH...AND THOSE WILL
TRACK TOWARDS THE REGION...KEEPING UNSETTLED WEATHER IN THE FORECAST
THROUGH THE END OF THE WEEK.
THE HIGH MOVES TO THE EAST THURSDAY NIGHT...AND THEN THE UPPER
TROUGH MOVES INTO THE EASTERN U.S. THERE ARE SOME INDICATIONS THAT
THE TROUGH BECOMES NEGATIVELY TILTED...AND THEN LOW PRES WILL
DEVELOP OVER THE MID-ATLANTIC BEFORE MOVING THROUGH THE REGION
THURSDAY NIGHT THROUGH FRIDAY. WILL BUMP UP POPS TO LIKELY FOR MOST
OF THE REGION FOR THAT TIME FRAME. COULD BE SOME LINGERING SHOWERS
INTO SATURDAY AS SEVERAL STRONG SHORTWAVES DIVE INTO THE REGION AS
THE TROUGH MOVES OVERHEAD.
SUMMER-LIKE TEMPS CONTINUE ON MONDAY WITH HIGHS WELL ABOVE
NORMAL...TOPPING OFF IN THE LOW 80S WEST OF THE HUDSON RIVER AND IN
THE MID TO UPPER 70S MOST ELSEWHERE...AND COOLER NEAR THE COASTS.
TEMPS RETURN CLOSER TO NORMAL ON TUESDAY...TOPPING OFF IN THE UPPER
60S TO LOWER 70S WITH THE WARMEST TEMPS ONCE AGAIN WEST OF THE
HUDSON RIVER. BY WEDNESDAY...BEHIND THE BACK DOOR COLD FRONT AND
WITH ONSHORE FLOW...HIGHS WILL RANGE FROM THE UPPER 50S NEAR THE
COASTS TO THE MID 60S ACROSS THE INTERIOR. TEMPS WILL THEN TOP OFF
AROUND NORMAL TO CLOSE OUT THE WEEK...GENERALLY IN THE UPPER 60S.
&&
.AVIATION /05Z SUNDAY THROUGH THURSDAY/...
A COLD FRONT WILL PASSING THROUGH THE REGION OVERNIGHT...FOLLOWED
BY WEAK HIGH PRESSURE FOR SUNDAY.
GENERALLY VFR THROUGH THE PERIOD.
LIGHT TO MODERATE SHOWERS BETWEEN 05-08Z. A LOW CHANCE OF THUNDER
IS POSSIBLE...BUT CONFIDENCE IS TOO LOW TO INCLUDE IN THE TAF. CIGS
COULD BRIEFLY DROP TO AROUND 3000 FT WITH ANY SHOWER ACTIVITY
HOWEVER WE ARE GENERALLY EXPECTING 4000-5000 FT CIGS WITH ANY
PCPN.
WEST-SOUTHWEST WINDS WILL SHIFT TO THE WEST-NORTHWEST BEHIND THE
FRONT. WIND SPEEDS WILL INCREASE DURING THE DAY SUNDAY...WITH GUSTS
MIXING IN AFTER 15Z. GUSTS INTO THE UPPER TEENS AND LOWER 20S. WINDS
TOMORROW MORNING/AFTN WILL HOVER AROUND 300 TRUE.
DRY WEATHER IS EXPECTED ON SUNDAY.
.OUTLOOK FOR 06Z MON THROUGH THURS...
.SUN NIGHT-MON...VFR.
.TUES-THURS...GENERALLY VFR WITH PERIODS OF MVFR OR LOWER WITH
PCPN.
&&
.MARINE...
PATCHY FOG CAN BE EXPECTED ACROSS THE WATERS TONIGHT WITH MOIST
LOW LEVELS. WINDS AND SEAS DIMINISHING TONIGHT...AND THOUGH WINDS
MAY BRIEFLY INCREASE IN THE WAKE OF THE COLD FRONT...NOT
ANTICIPATING ENOUGH TO REACH SCA CRITERIA ONCE AGAIN.
THEREFORE...HAVE CANCELLED THE SCA ON THE OCEAN WATERS.
SUB-SCA CONDITIONS ON TAP FOR SUNDAY INTO THE START THE NEW WEEK
WITH HIGH PRESSURE IN CONTROL. BY THE MIDDLE OF NEXT WEEK...SMALL
CRAFT CONDITIONS RETURN AS A PERSISTENT ONSHORE FLOW WILL HELP
PUSH OCEAN SEAS UP TO 3-5 FT.
&&
.HYDROLOGY...
UP TO AROUND A QUARTER INCH OF BASIN AVERAGE QPF IS POSSIBLE
THROUGH THE REMAINDER OF THE NIGHT. ANY FLOODING POTENTIAL IS
EXPECTED TO BE GENERALLY MINOR...PARTICULARLY FOR THOSE LOCATIONS
GETTING MULTIPLE ROUNDS OF SHOWERS AND THUNDERSTORMS.
SCATTERED SHOWERS/TSTMS COULD PRODUCE LOCALLY HEAVY RAIN FOR MOST OF
THE UPCOMING WEEK...BUT WIDESPREAD ORGANIZED PRECIPITATION OF 1/2"
QPF OR MORE WILL HOLD OFF UNTIL LATE NEXT WEEK WHEN LOW PRESSURE
TRACKS THROUGH THE REGION.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...NONE.
NY...NONE.
NJ...NONE.
MARINE...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
337 AM EDT SUN MAY 11 2014
.SYNOPSIS...
WEAK HIGH PRESSURE WILL REMAIN IN CONTROL OF THE REGION THROUGH
TUESDAY...WITH MAINLY AFTERNOON SHOWERS AND THUNDERSTORMS BEING
POSSIBLE. A COLD FRONT WILL MOVE INTO THE AREA ON WEDNESDAY AND
THURSDAY PROVIDING INCREASING CHANCES OF SHOWERS AND
THUNDERSTORMS.
&&
.NEAR TERM /THROUGH TODAY/...
EARLY THIS MORNING...REGIONAL RADAR IMAGERY SHOWS ISOLATED SHOWERS
MAINLY ACROSS THE EXTREME EASTERN MIDLANDS THIS MORNING. EXPECT
THE SHOWERS TO CONTINUE MOVING NORTHEASTWARD AND TO DISSIPATE OVER
THE NEXT COUPLE OF HOURS. HAVE ADJUSTED POPS AND CLOUDS THROUGH
THE EARLY MORNING HOURS TO ACCOUNT FOR CURRENT SITUATION.
TEMPERATURES REMAIN ON TRACK FOR LOWER 60S IN THE WESTERN MIDLANDS
AND MIDDLE TO UPPER 60S ELSEWHERE.
TODAY...AN UPPER RIDGE WILL BUILD OVER THE FORECAST AREA TODAY
WITH HIGH PRESSURE OVER THE WESTERN ATLANTIC RIDGING IN AT THE
SURFACE. DESPITE WEAK DYNAMICS...THE SPC WRF AND HRRR ARE IN FAVOR
OF ISOLATED SHOWERS AND THUNDERSTORMS DURING THE AFTERNOON HOURS.
MOISTURE APPEARS HIGHEST IN THE SOUTHEASTERN SECTION OF THE
FORECAST AREA. CONTINUED TO INDICATE ONLY A SLIGHT CHANCE OF
AFTERNOON SHOWERS AND THUNDERSTORMS WITH THE BEST CHANCE
SOUTHEAST. ABOVE NORMAL AFTERNOON HIGHS IN THE UPPER 80S WITH
LIGHT SOUTH/SOUTHWESTERLY WINDS.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
CAN NOT RULE OUT SOME SCATTERED LINGERING RAINFALL ACROSS EASTERN
PORTIONS OF THE CWA EARLY TONIGHT...THEN ALL AREAS DRYING OUT BY
MIDNIGHT. ON MONDAY THE UPPER RIDGE OFF THE ATLANTIC TRIES TO
BUILD WESTWARD BACK ACROSS THE AREA. SURFACE WIND FLOW OFF THE
ATLANTIC WILL CONTINUE TO BRING MOISTURE INTO THE REGION. WITH
AFTERNOON TEMPERATURES FORECAST AROUND 90...CAN NOT RULE OUT
ISOLATED TO SCATTERED AFTERNOON SHOWERS OR STORMS. LIMITING FACTOR
WOULD BE THE LACK OF ANY WELL DEFINED SURFACE FRONT. BEST CHANCE
AT THIS TIME WOULD APPEAR TO BE ACROSS THE EASTERN PORTIONS OF THE
CWA CLOSER TO THE SEA-BREEZE FRONT. ANY ACTIVITY SHOULD DIMINISH
AFTER SUNSET. OVERNIGHT LOWS MONDAY NIGHT REMAIN MILD...WITH
READINGS IN THE MIDDLE 60S.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
ONLY MADE MINOR CHANGES IN THE LONGER TERM AT THIS TIME. MODELS IN
GENERAL AGREEMENT EARLY IN THE PERIOD...THEN THE GFS AND ECMWF
DIVERGE ON THE STRENGTH OF A FORECAST UPPER TROUGH BY THE END OF
THE WEEK.
BERMUDA HIGH IN PLACE ON TUESDAY FOR THE REGION...WITH AN UPPER TROUGH
OVER THE MID PART OF THE COUNTRY. ALTHOUGH THE HIGH OFF THE COAST
WILL DOMINATE INTO MID WEEK...INCREASING MOISTURE AND TEMPERATURES
WILL RESULT IN A CHANCE OF A FEW AFTERNOON THUNDERSTORMS TUESDAY.
THE DIURNAL ACTIVITY WILL DIMINISH OVERNIGHT AND THEN THE CHANCE
OF AFTERNOON THUNDERSTORMS INCREASES WEDNESDAY. AS THE NEXT SYSTEM
SLOWLY APPROACHES THE AREA AND MOVES THROUGH ON THURSDAY EXPECT
THE CHANCE OF RAIN TO CONTINUE. HAVE RAISED THE POPS INTO THE
LIKELY CATEGORY FOR THURSDAY...WITH DIMINISHING POPS BEGINNING
THURSDAY EVENING. WILL HAVE TO CONTINUE TO WATCH THE TIMING AND
PROGRESSION OF THE UPPER TROUGH THOUGH. TEMPERATURES AHEAD OF THE
NEXT SYSTEM SHOULD BE ABOVE NORMAL IN THE UPPER 80S TUESDAY AND
WEDNESDAY AND THEN AS CLOUDS AND PRECIPITATION MOVE IN...HIGHS
WILL BE SOMEWHAT COOLER THE REMAINDER OF THE WEEK IN THE UPPER 70S
TO AROUND 80.
&&
.AVIATION /07Z SUNDAY THROUGH THURSDAY/...
EXPECT MAINLY VFR CONDITIONS THROUGH THE PERIOD AT CAE/CUB/DNL.
WITH LOW DEW POINT DEPRESSIONS AND PLENTY OF LOW LEVEL MOISTURE IN
PLACE THINK AGS/OGB COULD HAVE MVFR VSBYS 08Z-12Z WITH POSSIBLE
TEMPORARY IFR VSBYS AND/OR CIGS. MODEL GUIDANCE HAS NOT BEEN
AGGRESSIVE WITH FOG DEVELOPMENT. HOWEVER...GIVEN THE RESTRICTIONS
THAT OCCURRED YESTERDAY MORNING AND THAT SEVERAL STATIONS UPSTREAM
ARE INDICATING REDUCED VISIBILITIES ALREADY...CONFIDENCE IS
INCREASED.
VFR CONDITIONS EXPECTED AT ALL TERMINALS BY 14Z WITH LIGHT
SOUTHWEST WINDS THROUGH THE DAY. AN UPPER RIDGE WILL BUILD OVER
THE REGION TODAY WHICH SHOULD LIMIT PRECIPITATION. HOWEVER... SOME
MODELS ARE INDICATING AFTERNOON SHOWERS AND THUNDERSTORMS
DEVELOPING. CONFIDENCE IN TIMING AND COVERAGE IS TOO LOW TO
INCLUDE IN CURRENT TAF ISSUANCE.
.EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE WEDNESDAY NIGHT
INTO THURSDAY WITH SHARP UPPER TROUGH APPROACHING THE AREA
RESULTING IN SHOWERS AND THUNDERSTORMS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
227 AM EDT SUN MAY 11 2014
.SYNOPSIS...
WEAK HIGH PRESSURE WILL REMAIN IN CONTROL OF THE REGION THROUGH
TUESDAY. A COLD FRONT WILL MOVE INTO THE AREA ON WEDNESDAY AND
THURSDAY PROVIDING INCREASING CHANCES OF SHOWERS AND
THUNDERSTORMS.
&&
.NEAR TERM /THROUGH TONIGHT/...
REGIONAL RADAR IMAGERY SHOWS WIDELY SCATTERED SHOWERS MAINLY
ACROSS THE SOUTHEASTERN MIDLANDS THIS MORNING. EXPECT THE SHOWERS
TO CONTINUE MOVING NORTHEASTWARD AND TO DISSIPATE OVER THE NEXT
COUPLE OF HOURS. HAVE ADJUSTED POPS AND CLOUDS THROUGH THE EARLY
MORNING HOURS TO ACCOUNT FOR CURRENT SITUATION. TEMPERATURES
REMAIN ON TRACK FOR LOWER 60S IN THE WESTERN MIDLANDS AND MIDDLE
TO UPPER 60S ELSEWHERE.
AN UPPER RIDGE WILL BUILD OVER THE FORECAST AREA TODAY WITH HIGH
PRESSURE OVER THE WESTERN ATLANTIC RIDGING IN AT THE SURFACE.
DESPITE WEAK DYNAMICS...THE SPC WRF AND HRRR ARE IN FAVOR OF
ISOLATED SHOWERS AND THUNDERSTORMS DURING THE AFTERNOON HOURS.
MOISTURE APPEARS HIGHEST IN THE SOUTHEASTERN SECTION OF THE
FORECAST AREA. CONTINUED TO INDICATE ONLY A SLIGHT CHANCE OF
AFTERNOON SHOWERS AND THUNDERSTORMS WITH THE BEST CHANCE SOUTHEAST.
ABOVE NORMAL AFTERNOON HIGHS IN THE UPPER 80S WITH LIGHT
SOUTH/SOUTHWESTERLY WINDS.
&&
.SHORT TERM /MONDAY THROUGH MONDAY NIGHT/...
THE GFS AND ESPECIALLY THE NAM SHOW MORE MOISTURE LINGERING MAINLY
IN THE SOUTHEAST SECTION THROUGH MONDAY NIGHT. A WELL-DEFINED
SURFACE FEATURE APPEARS TO BE LACKING. ALOFT...THE MODELS SHOW
RISING H5 HEIGHT. WE USED THE LOWER GUIDANCE POPS. BELIEVE ANY
SHOWERS AND THUNDERSTORMS WILL BE ISOLATED AND MAINLY TIED TO
HEATING. KEPT HIGHS SLIGHTLY HIGHER THAN THE MOS GUIDANCE GIVEN
RECENT VERIFICATION...UPPER RIDGING...AND THE DRY ENVIRONMENTAL
CONDITIONS. USED THE MOS CONSENSUS FOR THE LOW TEMPERATURES.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
MODELS IN GENERAL AGREEMENT ON TUESDAY WITH BERMUDA HIGH IN PLACE
FOR THE SE US AND AN UPPER TROUGH OVER THE MID PART OF THE COUNTRY.
THE PROGRESSION EASTWARD OF THE UPPER TROUGH HAS SLOWED IN LATEST
MODEL RUNS. WHILE THE HIGH OFF THE COAST WILL DOMINATE INTO MID
WEEK...INCREASING MOISTURE AND TEMPERATURES WILL RESULT IN A CHANCE
OF A FEW AFTERNOON THUNDERSTORMS TUESDAY. THE DIURNAL ACTIVITY WILL
DIMINISH OVERNIGHT AND THEN THE CHANCE OF AFTERNOON THUNDERSTORMS
INCREASES WEDNESDAY. AS THE NEXT SYSTEM SLOWLY APPROACHES THE AREA
AND MOVES THROUGH ON THURSDAY EXPECT THE CHANCE OF RAIN TO CONTINUE
AND ATTM EXPECT THE HIGHEST CHANCE TO BE THURSDAY
AFTERNOON/EVENING. WILL HAVE TO CONTINUE TO WATCH THE TIMING AND
PROGRESSION OF THE UPPER TROUGH. TEMPERATURES AHEAD OF THE NEXT
SYSTEM SHOULD BE ABOVE NORMAL IN THE UPPER 80S TUESDAY AND
WEDNESDAY AND THEN AS CLOUDS AND PRECIPITATION MOVE IN...HIGHS
WILL BE SOMEWHAT COOLER THE REMAINDER OF THE WEEK IN THE UPPER 70S
TO AROUND 80.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
EXPECT MAINLY VFR CONDITIONS THROUGH THE PERIOD AT CAE/CUB/DNL.
WITH LOW DEW POINT DEPRESSIONS AND PLENTY OF LOW LEVEL MOISTURE IN
PLACE THINK AGS/OGB COULD HAVE MVFR VSBYS 08Z-12Z WITH POSSIBLE
TEMPORARY IFR VSBYS AND/OR CIGS. MODEL GUIDANCE HAS NOT BEEN
AGGRESSIVE WITH FOG DEVELOPMENT. HOWEVER...GIVEN THE RESTRICTIONS
THAT OCCURRED YESTERDAY MORNING AND THAT SEVERAL STATIONS UPSTREAM
ARE INDICATING REDUCED VISIBILITIES ALREADY...CONFIDENCE IS
INCREASED.
VFR CONDITIONS EXPECTED AT ALL TERMINALS BY 14Z WITH LIGHT
SOUTHWEST WINDS THROUGH THE DAY. AN UPPER RIDGE WILL BUILD OVER
THE REGION TODAY WHICH SHOULD LIMIT PRECIPITATION. HOWEVER... SOME
MODELS ARE INDICATING AFTERNOON SHOWERS AND THUNDERSTORMS
DEVELOPING. CONFIDENCE IN TIMING AND COVERAGE IS TOO LOW TO
INCLUDE IN CURRENT TAF ISSUANCE.
.EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE WEDNESDAY NIGHT
INTO THURSDAY WITH SHARP UPPER TROUGH APPROACHING THE AREA
RESULTING IN SHOWERS AND THUNDERSTORMS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
230 AM EDT SUN MAY 11 2014
.UPDATE...
THE LONG TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 245 PM EDT SAT MAY 10 2014
A FRONT WILL MEANDER ACROSS THE AREA THIS WEEKEND KEEPING CHANCES
FOR RAIN IN THE FORECAST. ANOTHER FRONT WILL BRING MORE RAIN CHANCES
NEXT WEEK. TEMPERATURES WILL WARM TO ABOVE AVERAGE BY EARLY NEXT
WEEK...THEN FALL TO BELOW AVERAGE FROM MID WEEK ON BEHIND THE COLD
FRONT.
&&
.NEAR TERM /OVERNIGHT/...
ISSUED AT 1004 PM EDT SAT MAY 10 2014
CLOUD DEBRIS FROM WARM FRONTAL CONVECTION ACROSS MISSOURI ALREADY
RETURNING INTO THE HOOSIER STATE AS OF 0130Z. TEMPS WERE PRIMARILY
IN THE 60S AT THE MID EVENING POINT.
FRONTAL BOUNDARY AT 0130Z EXTENDING ACROSS FAR SOUTHERN INDIANA
BACK TO NEAR KSTL THEN CONTINUING WEST INTO NORTH CENTRAL
MISSOURI. BOUNDARY ALREADY SHOWING SIGNS OF LIFTING BACK NORTH
OVER THE LAST FEW HOURS...AND WILL CONTINUE TO DO SO OVERNIGHT.
IMPRESSIVE POCKET OF DRY AIR HAS SLIPPED SOUTH INTO NORTHERN PORTIONS
OF THE FORECAST AREA...WITH DEWPOINTS INTO THE MIDDLE/UPPER 30S
FROM INDY NORTHEAST. THESE LOWER DEWPOINTS WILL QUICKLY RECOVER AS
THE BOUNDARY RETURNS INTO THE FORECAST AREA OVER THE NEXT SEVERAL
HOURS.
THE MAIN ISSUE FOR THE UPDATE IS THE EXPECTED TRACK OF THE
CONVECTION ACROSS THE MID MISSISSIPPI VALLEY AND THE STATE OF
INTENSITY ITS LIKELY TO BE IN WHEN IT ARRIVES IN THE REGION. BOTH
THE RAP AND HRRR MOVE CONVECTION ALONG THE WARM FRONT OVER THE
NEXT FEW HOURS...LIKELY REACHING THE WABASH RIVER BETWEEN KHUF AND
KLWV BY AROUND 07Z. EXPECT SHOWERS AND EMBEDDED STORMS TO
OVERSPREAD PRIMARILY THE SOUTHERN HALF OF THE FORECAST AREA IN A
WEAKENED CONDITION THEREAFTER AS THE WARM FRONT LIFTS NORTH. WILL
CARRY LOWER POPS FURTHER NORTH.
OVERNIGHT LOWS RANGING FROM THE MID 50S OVER NORTHEAST COUNTIES TO
THE MID 60S IN THE LOWER WABASH VALLEY LOOK REASONABLE AND LITTLE
CHANGE WAS MADE. ZONE AND GRID UPDATES OUT.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
ISSUED AT 245 PM EDT SAT MAY 10 2014
FOCUS WILL CONTINUE TO BE ON THUNDERSTORM CHANCES THROUGH THE ENTIRE
SHORT TERM AS LOW PRESSURE SYSTEM GRADUALLY MIGRATES EAST FROM THE
PLAINS.
ECMWF CONTINUES TO BE THE MOST CONSISTENT OF THE MODELS REGARD
SLOWLY MOVING FRONTAL SYSTEM. ASSOCIATED COLD FRONT LOOKS LIKE IT
WILL NOT MOVE ACROSS CENTRAL INDIANA UNTIL TUESDAY AFTERNOON AND
NIGHT.
ON SUNDAY...WARM FRONT SHOULD LIFT NORTHEAST ACROSS CENTRAL INDIANA
WHICH SHOULD TRIGGER SCATTERED THUNDERSTORMS WITH MODELS ALL SHOWING
MIXED LAYER CAPES FROM 1000-2000 J/KG...INCREASED LOW LEVEL MOISTURE
AND SOME RESULTING QPF. THEN...WITH THE AREA IN THE WARM SECTOR FROM
SUNDAY NIGHT THROUGH MONDAY NIGHT...SHOULD SEE WARMER TEMPERATURES
IN THE 80S ON MONDAY PER 12Z MOS BLEND AND CONSALL. WILL STICK WITH
LOW POPS SUNDAY NIGHT THROUGH MONDAY NIGHT WITH AMPLE INSTABILITY
AND POSSIBLY LEFTOVER OUTFLOW BOUNDARIES BUT ONLY WEAK SYNOPTIC
FORCING WITH UPPER WAVES IN SOUTHWEST FLOW.
BEST CHANCE OF THUNDERSTORMS WILL BE ON TUESDAY AS THE FRONT
APPROACHES AND MOVES AT LEAST PART OF THE WAY ACROSS THE FORECAST
AREA.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
ISSUED AT 230 AM EDT SUN MAY 11 2014
CONFIDENCE IS BUILDING FOR PRECIP EVENT ON WEDNESDAY AS THE GFS
AND ECMWF CONTINUE TO SUGGEST THE LAST OF THE DYNAMICS ASSOCIATED
WITH AN APPROACHING TROUGH WILL PASS INTO INDIANA. HAVE RAISED
POPS HERE.
CONFIDENCE WANES LATER IN THE FORECAST PERIOD. GFS AND ECMWF
CONTINUE TO SUGGEST THAT BROAD CYCLONIC FLOW WILL REMAIN IN PLACE
ACROSS THE REGION...HOWEVER COOL AND DRY NORTHWEST LOWER LEVEL
FLOW IS EXPECTED TO PERSIST...LIMITING MOISTURE. THUS HAVE TRENDED
DRIER AND COOLER DURING THIS PERIOD.
&&
.AVIATION /DISCUSSION FOR 110600Z TAF ISSUANCE/...
ISSUED AT 1259 AM EDT SUN MAY 11 2014
SITES WILL START OUT VFR AND DRY WITH A FRONT ACROSS SOUTHERN
INDIANA. THIS WILL SLOWLY LIFT NORTH AS A WARM FRONT. SHOWERS AND
THUNDERSTORMS OVER CENTRAL ILLINOIS WILL MOVE IN TO THE SITES
STARTING AFTER ABOUT 8Z. UNCERTAIN HOW MUCH THUNDER WILL BE LEFT AT
THAT POINT...SO WILL INCLUDE A VCTS WITH SHOWERS. EXPECT WINDS TO BE
LIGHT AND VARIABLE FOR A FEW HOURS BUT PICK UP AGAIN SUNDAY MORNING
OUT OF THE SOUTHEAST AND THEN SOUTH BY SUNDAY AFTERNOON...AROUND 5-8
KTS IN THE MORNING THEN 10-15 KTS IN THE AFTERNOON.
MORE CHANCES FOR RAIN AND THUNDER ARE IN THE FORECAST FOR SUNDAY
AFTERNOON...BUT UNCERTAINTY IS HIGH ENOUGH TO LEAVE OUT FOR NOW AND
JUST INCLUDE A BROKEN DECK.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...MK
NEAR TERM...RYAN
SHORT TERM...MK
LONG TERM....PUMA
AVIATION...CP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
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AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1259 AM EDT SUN MAY 11 2014
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 245 PM EDT SAT MAY 10 2014
A FRONT WILL MEANDER ACROSS THE AREA THIS WEEKEND KEEPING CHANCES
FOR RAIN IN THE FORECAST. ANOTHER FRONT WILL BRING MORE RAIN CHANCES
NEXT WEEK. TEMPERATURES WILL WARM TO ABOVE AVERAGE BY EARLY NEXT
WEEK...THEN FALL TO BELOW AVERAGE FROM MID WEEK ON BEHIND THE COLD
FRONT.
&&
.NEAR TERM /OVERNIGHT/...
ISSUED AT 1004 PM EDT SAT MAY 10 2014
CLOUD DEBRIS FROM WARM FRONTAL CONVECTION ACROSS MISSOURI ALREADY
RETURNING INTO THE HOOSIER STATE AS OF 0130Z. TEMPS WERE PRIMARILY
IN THE 60S AT THE MID EVENING POINT.
FRONTAL BOUNDARY AT 0130Z EXTENDING ACROSS FAR SOUTHERN INDIANA
BACK TO NEAR KSTL THEN CONTINUING WEST INTO NORTH CENTRAL
MISSOURI. BOUNDARY ALREADY SHOWING SIGNS OF LIFTING BACK NORTH
OVER THE LAST FEW HOURS...AND WILL CONTINUE TO DO SO OVERNIGHT.
IMPRESSIVE POCKET OF DRY AIR HAS SLIPPED SOUTH INTO NORTHERN PORTIONS
OF THE FORECAST AREA...WITH DEWPOINTS INTO THE MIDDLE/UPPER 30S
FROM INDY NORTHEAST. THESE LOWER DEWPOINTS WILL QUICKLY RECOVER AS
THE BOUNDARY RETURNS INTO THE FORECAST AREA OVER THE NEXT SEVERAL
HOURS.
THE MAIN ISSUE FOR THE UPDATE IS THE EXPECTED TRACK OF THE
CONVECTION ACROSS THE MID MISSISSIPPI VALLEY AND THE STATE OF
INTENSITY ITS LIKELY TO BE IN WHEN IT ARRIVES IN THE REGION. BOTH
THE RAP AND HRRR MOVE CONVECTION ALONG THE WARM FRONT OVER THE
NEXT FEW HOURS...LIKELY REACHING THE WABASH RIVER BETWEEN KHUF AND
KLWV BY AROUND 07Z. EXPECT SHOWERS AND EMBEDDED STORMS TO
OVERSPREAD PRIMARILY THE SOUTHERN HALF OF THE FORECAST AREA IN A
WEAKENED CONDITION THEREAFTER AS THE WARM FRONT LIFTS NORTH. WILL
CARRY LOWER POPS FURTHER NORTH.
OVERNIGHT LOWS RANGING FROM THE MID 50S OVER NORTHEAST COUNTIES TO
THE MID 60S IN THE LOWER WABASH VALLEY LOOK REASONABLE AND LITTLE
CHANGE WAS MADE. ZONE AND GRID UPDATES OUT.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
ISSUED AT 245 PM EDT SAT MAY 10 2014
FOCUS WILL CONTINUE TO BE ON THUNDERSTORM CHANCES THROUGH THE ENTIRE
SHORT TERM AS LOW PRESSURE SYSTEM GRADUALLY MIGRATES EAST FROM THE
PLAINS.
ECMWF CONTINUES TO BE THE MOST CONSISTENT OF THE MODELS REGARD
SLOWLY MOVING FRONTAL SYSTEM. ASSOCIATED COLD FRONT LOOKS LIKE IT
WILL NOT MOVE ACROSS CENTRAL INDIANA UNTIL TUESDAY AFTERNOON AND
NIGHT.
ON SUNDAY...WARM FRONT SHOULD LIFT NORTHEAST ACROSS CENTRAL INDIANA
WHICH SHOULD TRIGGER SCATTERED THUNDERSTORMS WITH MODELS ALL SHOWING
MIXED LAYER CAPES FROM 1000-2000 J/KG...INCREASED LOW LEVEL MOISTURE
AND SOME RESULTING QPF. THEN...WITH THE AREA IN THE WARM SECTOR FROM
SUNDAY NIGHT THROUGH MONDAY NIGHT...SHOULD SEE WARMER TEMPERATURES
IN THE 80S ON MONDAY PER 12Z MOS BLEND AND CONSALL. WILL STICK WITH
LOW POPS SUNDAY NIGHT THROUGH MONDAY NIGHT WITH AMPLE INSTABILITY
AND POSSIBLY LEFTOVER OUTFLOW BOUNDARIES BUT ONLY WEAK SYNOPTIC
FORCING WITH UPPER WAVES IN SOUTHWEST FLOW.
BEST CHANCE OF THUNDERSTORMS WILL BE ON TUESDAY AS THE FRONT
APPROACHES AND MOVES AT LEAST PART OF THE WAY ACROSS THE FORECAST
AREA.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
ISSUED AT 245 PM EDT SAT MAY 10 2014
ENSEMBLES INDICATE A SLOWLY PROGRESSIVE NATURE TO THE MAIN UPPER
FEATURES DURING THIS PERIOD. A DEEP TROUGH THAT IS EXPECTED TO BE
OVER THE MIDWEST BY THE MIDDLE OF NEXT WEEK WILL GRADUALLY SETTLE
INTO THE GREAT LAKES/OHIO VALLEY BY NEXT WEEKEND.
SOME OF THE ENSEMBLES SUGGEST A SECONDARY WAVE OF LOW PRESSURE MAY
DEVELOP ALONG THE MAIN FRONT TOWARDS THE MIDDLE OF NEXT WEEK WHILE
OTHERS ARE QUICKER WITH THE PASSAGE OF THE FRONT. IN EITHER
CASE...IT APPEARS THE HIGHEST PRECIPITATION THREAT WILL BE TUESDAY
NIGHT INTO WEDNESDAY WITH THE PASSAGE OF THE SURFACE FRONT AND
POTENTIAL SECONDARY WAVE.
AFTER THAT...COOL AND SHOWERY CONDITIONS EXPECTED INTO NEXT WEEKEND
ASSOCIATED WITH THE INSTABILITY NEAR THE DEEP UPPER TROUGH AND ANY
POTENTIAL DISTURBANCES THAT MAY RIPPLE THROUGH IT. WILL KEEP POPS
GOING THROUGHOUT THE EXTENDED PERIOD.
&&
.AVIATION /DISCUSSION FOR 110600Z TAF ISSUANCE/...
ISSUED AT 1259 AM EDT SUN MAY 11 2014
SITES WILL START OUT VFR AND DRY WITH A FRONT ACROSS SOUTHERN
INDIANA. THIS WILL SLOWLY LIFT NORTH AS A WARM FRONT. SHOWERS AND
THUNDERSTORMS OVER CENTRAL ILLINOIS WILL MOVE IN TO THE SITES
STARTING AFTER ABOUT 8Z. UNCERTAIN HOW MUCH THUNDER WILL BE LEFT AT
THAT POINT...SO WILL INCLUDE A VCTS WITH SHOWERS. EXPECT WINDS TO BE
LIGHT AND VARIABLE FOR A FEW HOURS BUT PICK UP AGAIN SUNDAY MORNING
OUT OF THE SOUTHEAST AND THEN SOUTH BY SUNDAY AFTERNOON...AROUND 5-8
KTS IN THE MORNING THEN 10-15 KTS IN THE AFTERNOON.
MORE CHANCES FOR RAIN AND THUNDER ARE IN THE FORECAST FOR SUNDAY
AFTERNOON...BUT UNCERTAINTY IS HIGH ENOUGH TO LEAVE OUT FOR NOW AND
JUST INCLUDE A BROKEN DECK.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...MK
NEAR TERM...RYAN
SHORT TERM...MK
LONG TERM....JAS
AVIATION...CP
VISIT US AT HTTP://WWW.WEATHER.GOV/IND
FOLLOW US ON TWITTER AND YOUTUBE AT:
WWW.TWITTER.COM/NWSINDIANAPOLIS
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AREA FORECAST DISCUSSION...CORRECTED
NWS NEW ORLEANS LA
355 AM CDT SUN MAY 11 2014
.DISCUSSION...
GENERALLY ONLY MINOR CHANGES MADE TO THE FORECAST WITH THIS
PACKAGE AS FORECAST REASONING HASN/T CHANGED AND MODELS ARE
COMING INTO BETTER AGREEMENT CONCERNING THE MID WEEK COLD FRONT.
MUGGY CONDITIONS WILL STICK AROUND THROUGH MID WEEK AS ONSHORE
WINDS CONTINUE TO RESULT IN AN INFLUX OF WARM AND MOIST AIR INTO
THE REGION FROM THE GULF OF MEXICO. THIS WILL KEEP TEMPERATURES...
ESPECIALLY OVERNIGHT...ABOVE NORMAL. AFTERNOON TEMPERATURES
GENERALLY FORECAST TO TOP OUT IN THE MID TO UPPER 80S WITH
OVERNIGHT LOWS STRUGGLING TO DROP BELOW 70 DEGREES.
EXPECT DIURNALLY FORCED CONVECTION EACH AFTERNOON WITH GENERALLY
ISOLATED TO WIDELY SCATTERED COVERAGE. LATEST MODEL RUNS...BOTH
SYNOPTIC AND MESOSCALE...ARE A BIT MORE AGGRESSIVE DEVELOPING
CONVECTION TODAY SO HAVE BUMPED POPS UP TO SOLID CHANCE...AROUND
40 PERCENT...FOR MOST OF THE AREA. LATEST HRRR AND NCEP WRF RUNS
INDICATE SOME CONVECTION DEVELOPING OVER THE NORTHERN GULF BY 14Z
OR 15Z AND THEN MOVING OR SPREADING INLAND BY EARLY AFTERNOON. ON
AVERAGE...QPF SHOULD BE LESS THAN A QUARTER INCH...BUT A FEW
PLACES COULD SEE UP TO AN INCH OF RAIN TODAY IF IMPACTED BY A
HEAVIER STORM OR TWO. SIMILAR CONDITIONS EXPECTED MONDAY...
THOUGH COVERAGE SHOULD BE SLIGHTLY LESS. AM CARRYING 20 TO 30
PERCENT POPS ACROSS THE AREA MONDAY AFTERNOON.
BY TUESDAY...STRONG UPPER TROUGH WILL BE DIGGING INTO THE PLAINS
STATES AND FORCING A COLD FRONT TOWARD THE NORTHERN GULF COAST
REGION. MODELS HAVE COME INTO MUCH BETTER AGREEMENT CONCERNING
BOTH THE AMPLITUDE OF THIS TROUGH AND THE TIMING OF THE SURFACE
COLD FRONT. LOOKS LIKE THE SURFACE FRONT SHOULD PASS THROUGH THE
AREA SOME TIME LATE TUESDAY NIGHT OR EARLY WEDNESDAY MORNING...
WITH COOLER AND DRIER AIR FILTERING INTO THE AREA DURING THE DAY
WEDNESDAY. EXPECT A FAIRLY SIGNIFICANT TEMPERATURE DROP BEHIND THE
FRONT WITH AFTERNOON HIGHS ON WEDNESDAY CURRENTLY FORECAST TO BE
5 TO 10 DEGREES LOWER THAN HIGHS ON TUESDAY. THE REAL DIFFERENCE
WILL BE FELT AT NIGHT...THOUGH...WITH OVERNIGHT LOWS PLUNGING INTO
THE 50S WEDNESDAY NIGHT THROUGH FRIDAY NIGHT FOR MOST OF THE AREA.
NORTHWEST FLOW ALOFT WILL PREVAIL THROUGH THE REMAINDER OF THE
FORECAST PERIOD. MODELS CURRENTLY HINTING AT ANOTHER DISTURBANCE
MOVING INTO THE SOUTHEAST CONUS OVER THE WEEKEND...THOUGH BOTH THE
EURO AND GFS KEEP THE MOISTURE AND FORCING TO THE NORTHEAST OF THE
LOCAL AREA. WITH THIS IN MIND...AM KEEPING A DRY FORECAST THROUGH
THE WEEKEND AT THIS TIME.
&&
.AVIATION...
VARIABLE CONDITIONS WERE BEING OBSERVED EARLY THIS MORNING ACROSS
THE FORECAST AREA...RANGING FROM VFR TO LIFR DUE TO CEILINGS BEING
OBSERVED AT SOME OF THE TAF SITES. SOME GENERALLY LIGHT FOG WAS ALSO
IMPACTING A NUMBER OF THE TERMINALS. CONDITIONS ARE EXPECTED TO
IMPROVE TO VFR AT ALL LOCATIONS BY LATE MORNING OR EARLY AFTERNOON.
SCATTERED CONVECTION THIS AFTERNOON WILL BE POSSIBLE AT EACH OF THE
SITES. MVFR TO IFR CEILINGS WILL AGAIN BE POSSIBLE LATE TONIGHT AND
EARLY MONDAY MORNING.
&&
.MARINE...
MODERATE SOUTHEAST FLOW WILL CONTINUE ACROSS THE COASTAL WATERS
TODAY AND MONDAY BEFORE EASING ON TUESDAY. A COLD FRONT WILL PUSH
ACROSS THE COASTAL WATERS LATE TUESDAY NIGHT INTO WEDNESDAY WITH
STRONG OFFSHORE FLOW DEVELOPING IN ITS WAKE FROM LATE WEDNESDAY INTO
THURSDAY.
&&
.DECISION SUPPORT...
DSS CODE...BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...SLURRY SUPPORT
MONITORING RIVER FLOODING
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED
WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE TO HIGH RISK SVR
AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL
SIGNIFICANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 85 67 86 67 / 40 20 30 20
BTR 86 72 87 70 / 40 20 30 20
ASD 83 71 83 70 / 40 30 20 20
MSY 85 73 83 71 / 40 20 20 20
GPT 84 74 84 72 / 40 20 20 20
PQL 83 69 85 70 / 40 20 20 20
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&
$$
AVIATION/MARINE...11
REST OF DISCUSSION...95/DM
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
331 AM CDT SUN MAY 11 2014
.DISCUSSION...
GENERALLY ONLY MINOR CHANGES MADE TO THE FORECAST WITH THIS
PACKAGE AS FORECAST REASONING HASN/T CHANGED AND MODELS ARE
COMING INTO BETTER AGREEMENT CONCERNING THE MID WEEK COLD FRONT.
MUGGY CONDITIONS WILL STICK AROUND THROUGH MID WEEK AS ONSHORE
WINDS CONTINUE TO RESULT IN AN INFLUX OF WARM AND MOIST AIR INTO
THE REGION FROM THE GULF OF MEXICO. THIS WILL KEEP TEMPERATURES...
ESPECIALLY OVERNIGHT...ABOVE NORMAL. AFTERNOON TEMPERATURES
GENERALLY FORECAST TO TOP OUT IN THE MID TO UPPER 80S WITH
OVERNIGHT LOWS STRUGGLING TO DROP BELOW 70 DEGREES.
EXPECT DIURNALLY FORCED CONVECTION EACH AFTERNOON WITH GENERALLY
ISOLATED TO WIDELY SCATTERED COVERAGE. LATEST MODEL RUNS...BOTH
SYNOPTIC AND MESOSCALE...ARE A BIT MORE AGGRESSIVE DEVELOPING
CONVECTION TODAY SO HAVE BUMPED POPS UP TO SOLID CHANCE...AROUND
40 PERCENT...FOR MOST OF THE AREA. LATEST HRRR AND NCEP WRF RUNS
INDICATE SOME CONVECTION DEVELOPING OVER THE NORTHERN GULF BY 14Z
OR 15Z AND THEN MOVING OR SPREADING INLAND BY EARLY AFTERNOON. ON
AVERAGE...QPF SHOULD BE LESS THAN A QUARTER INCH...BUT A FEW
PLACES COULD SEE UP TO AN INCH OF RAIN TODAY IF IMPACTED BY A
HEAVIER STORM OR TWO. SIMILAR CONDITIONS EXPECTED MONDAY...
THOUGH COVERAGE SHOULD BE SLIGHTLY LESS. AM CARRYING 20 TO 30
PERCENT POPS ACROSS THE AREA MONDAY AFTERNOON.
BY TUESDAY...STRONG UPPER TROUGH WILL BE DIGGING INTO THE PLAINS
STATES AND FORCING A COLD FRONT TOWARD THE NORTHERN GULF COAST
REGION. MODELS HAVE COME INTO MUCH BETTER AGREEMENT CONCERNING
BOTH THE AMPLITUDE OF THIS TROUGH AND THE TIMING OF THE SURFACE
COLD FRONT. LOOKS LIKE THE SURFACE FRONT SHOULD PASS THROUGH THE
AREA SOME TIME LATE TUESDAY NIGHT OR EARLY WEDNESDAY MORNING...
WITH COOLER AND DRIER AIR FILTERING INTO THE AREA DURING THE DAY
WEDNESDAY. EXPECT A FAIRLY SIGNIFICANT TEMPERATURE DROP BEHIND THE
FRONT WITH AFTERNOON HIGHS ON WEDNESDAY CURRENTLY FORECAST TO BE
5 TO 10 DEGREES LOWER THAN HIGHS ON TUESDAY. THE REAL DIFFERENCE
WILL BE FELT AT NIGHT...THOUGH...WITH OVERNIGHT LOWS PLUNGING INTO
THE WEDNESDAY NIGHT THROUGH FRIDAY NIGHT FOR MOST OF THE AREA.
NORTHWEST FLOW ALOFT WILL PREVAIL THROUGH THE REMAINDER OF THE
FORECAST PERIOD. MODELS CURRENTLY HINTING AT ANOTHER DISTURBANCE
MOVING INTO THE SOUTHEAST CONUS OVER THE WEEKEND...THOUGH BOTH THE
EURO AND GFS KEEP THE MOISTURE AND FORCING TO THE NORTHEAST OF THE
LOCAL AREA. WITH THIS IN MIND...AM KEEPING A DRY FORECAST THROUGH
THE WEEKEND AT THIS TIME.
&&
.AVIATION...
VARIABLE CONDITIONS WERE BEING OBSERVED EARLY THIS MORNING ACROSS
THE FORECAST AREA...RANGING FROM VFR TO LIFR DUE TO CEILINGS BEING
OBSERVED AT SOME OF THE TAF SITES. SOME GENERALLY LIGHT FOG WAS ALSO
IMPACTING A NUMBER OF THE TERMINALS. CONDITIONS ARE EXPECTED TO
IMPROVE TO VFR AT ALL LOCATIONS BY LATE MORNING OR EARLY AFTERNOON.
SCATTERED CONVECTION THIS AFTERNOON WILL BE POSSIBLE AT EACH OF THE
SITES. MVFR TO IFR CEILINGS WILL AGAIN BE POSSIBLE LATE TONIGHT AND
EARLY MONDAY MORNING.
&&
.MARINE...
MODERATE SOUTHEAST FLOW WILL CONTINUE ACROSS THE COASTAL WATERS
TODAY AND MONDAY BEFORE EASING ON TUESDAY. A COLD FRONT WILL PUSH
ACROSS THE COASTAL WATERS LATE TUESDAY NIGHT INTO WEDNESDAY WITH
STRONG OFFSHORE FLOW DEVELOPING IN ITS WAKE FROM LATE WEDNESDAY INTO
THURSDAY.
&&
.DECISION SUPPORT...
DSS CODE...BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...SLURRY SUPPORT
MONITORING RIVER FLOODING
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED
WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE TO HIGH RISK SVR
AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL
SIGNIFICANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 85 67 86 67 / 40 20 30 20
BTR 86 72 87 70 / 40 20 30 20
ASD 83 71 83 70 / 40 30 20 20
MSY 85 73 83 71 / 40 20 20 20
GPT 84 74 84 72 / 40 20 20 20
PQL 83 69 85 70 / 40 20 20 20
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&
$$
AVIATION/MARINE...11
REST OF DISCUSSION...95/DM
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
456 AM EDT SUN MAY 11 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 454 AM EDT SUN MAY 11 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A SHORTWAVE HEADING SE
TOWARD THE SRN ROCKIES...LEADING THE TROF AMPLIFICATION DOWNSTREAM
OF ADVERTISED BUILDING RIDGE JUST OFF THE W COAST. DEEPENING TROF
AND SHORTWAVE WILL BRING THE NEXT ROUND OF WIDESPREAD WET WEATHER TO
THE UPPER GREAT LAKES...BEGINNING AS EARLY AS LATER TONIGHT. AHEAD
OF THE AMPLIFYING WRN TROF...A SHORTWAVE IS LIFTING THRU THE UPPER
MISSISSIPPI VALLEY. WITH LARGER SCALE RIDGE BUILDING OVER THE
MISSISSIPPI VALLEY/WRN LAKES DOWNSTREAM OF THE DEEPENING WRN
TROF...WAVE IS WEAKENING. LATEST RADAR IMAGERY SHOWS ISOLD/SCT
-SHRA ALONG THE MI/WI BORDER AREA. WITH VERY DRY MASS OVER
THE AREA (NOTE THE VERY DRY COLUMN SAMPLED BY 00Z KGRB SOUNDING)...
PCPN HAS BEEN ON THE LIGHT SIDE WITH MUCH OF IT NOT MORE THAN
SPRINKLES.
SOMEWHAT SURPRISED THAT -SHRA/SPRINKLES ARE HOLDING TOGETHER GIVEN
THE ANTECEDANT DRY AIR MASS AND THE SHORTWAVE/FORCING WEAKENING
UNDER DEVELOPING HEIGHT RISES. IN ANY EVENT...ISOLD/SCT
-SHRA/SPRINKLES SHOULD MOVE NE ACROSS ALL BUT THE FAR ERN FCST AREA
DURING THE MORNING. AFTER THE MORNING HRS...EXPECT A DRY AFTN UNDER
CONTINUED HEIGHT RISES AS RIDGE BUILDS THRU THE WRN GREAT LAKES
DOWNSTREAM OF ROCKIES TROF. YESTERDAY...A NUMBER OF MODELS WERE
SUGGESTING SOME AFTN CONVECTION...ESPECIALLY THE NAM. THAT IDEA WAS
DISREGARDED AS MODELS WERE OVERFORECASTING LOW-LEVEL MOISTURE AND
THUS INSTABILITY. WELL...TODAYS 00Z MODELS RUNS ARE ALMOST ALL
ONBOARD WITH A DRY AFTN AS A RESULT OF CORRECTING THE
MOISTURE/INSTABILITY DOWNWARD. CLOUDS WILL THIN SOME IN THE
AFTN...ALLOWING TEMPS TO RISE WELL INTO THE 60S TO AROUND 70F AWAY
FROM LAKE MODERATION.
AS STRONGER SHORTWAVE BEGINS TO EJECT OUT OF DEEPENING UPPER TROF
DRIFTING TOWARD THE WRN PLAINS TONIGHT...SFC LOW PRES WILL BEGIN TO
LIFT NE THRU THE PLAINS. ALTHOUGH THE EVENING MAY BE DRY...
ESPECIALLY OVER THE NE HALF OF THE FCST AREA CLOSER TO DRY LOW-LEVEL
NE TRAJECTORIES OUT OF SFC HIGH PRES IN ONTARIO...MOST OF THE MODELS
SHOW HIGHER MID LEVEL RH AND PCPN ARRIVING FROM THE SW THRU THE
NIGHT AS WAA/ISENTROPIC ASCENT REGIME SPREADS N. THERE ARE
INDICATIONS OF A SUBTLE SHORTWAVE LIFTING NE INTO THE UPPER
MISSISSIPPI VALLEY LATE TONIGHT...AND THAT WILL FURTHER AID THE
DEVELOPMENT/SPREAD OF SHRA NE INTO UPPER MI DURING THE OVERNIGHT.
NOT MUCH INSTABILITY IS NOTED PER 0-3KM MUCAPE OFF THE NAM/GFS. WITH
A COUPLE HUNDRED J/KG AND SHOWALTER INDEX FALLING JUST BLO 0 OVER
THE FAR SCNTRL LATE TONIGHT IN MOST MODEL GUIDANCE...WILL INCLUDE A
THUNDER MENTION IN THAT AREA LATE TONIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 454 AM EDT SUN MAY 11 2014
AGREEMENT IS HIGH IN OVERALL LARGER SCALE PATTERN FOR THE UPCOMING
WEEK. FLOW IS HIGHLY AMPLIFIED. INITIALY THIS WEEK TROUGH OVER THE
WESTERN CONUS THIS MORNING SLIDES ACROSS THE CENTRAL CONUS. SFC-H85
LOW PRESSURE BEGINS TO FORM TODAY OVER THE SOUTHERN PLAINS AND THIS
LOW LIFTS TOWARD UPPER MISSISSIPPI RIVER VALLEY BY DAYBREAK ON
MONDAY. SFC WARM FRONT SHOULD STAY SOUTH OF UPR MICHIGAN...MAINLY
OVER SOUTHERN/CENTRAL WI ACROSS CENTRAL LOWER MICHIGAN. EASTERLY
LOW-LEVEL WINDS OFF THE COLD GREAT LAKES TO THE NORTH OF THE FRONT
ALONG WITH SHRA/TSRA FIRING ALONG THE FRONT SHOULD KEEP THE WARM
FRONT FROM MOVING INTO UPR MICHIGAN ON MONDAY. WARM FRONT SOUTH OF
HERE ALONG WITH EASTERLY WINDS SHOULD KEEP TEMPS COOLER ON MONDAY
THAN THIS WEEKEND.
H85 WARM FRONT WILL BE IN THE VICINITY THOUGH AND THERE IS MOISTURE
TRANSPORT AT H85-H7 AIMED INTO THE H85 FRONT ALLOWING PWATS OVER 1.5
INCHES OR WELL OVER 200 PCT OF NORMAL TO PUSH NORTHWARD ACROSS UPPER
GREAT LAKES REGION. SHORTWAVE/PV ANAMOLY EMERGING NORTHEAST OUT OF
THE LARGE WESTERN CONUS TROUGH RESULTS IN AREA OF H85-H5 Q-VECTOR
CONVERGENCE SPREADING OVER UPPER GREAT LAKES ON MONDAY. ADDITIONAL
LIFT WILL BE PROVIDED VIA 250MB JET STREAK LIFTING NNE-SSW AHEAD OF
MAIN TROUGH AND ALSO ANOTHER SLIDING WNW-ESE OVER NORTHERN ONTARIO
TOWARD QUEBEC. AT FIRST GLANCE...A LOT OF THINGS ARE FAVORABLE FOR
MULTIPLE PERIODS OF SHOWERS OVER UPR MICHIGAN ON MONDAY. YET...THE
INSTABILITY BOTH ELEVATED /1-6KM MUCAPE/ AND AT THE SFC /MLCAPE/ IS
NOT AS FAVORABLE...WITH GRADIENT OF BOTH TO SOUTH AND SOUTHWEST OF
UPR MICHIGAN THROUGH THE DAY. MODELS DIFFER ON PLACEMENT OF MAXIMUM
MOISTURE ADVECTION AND THIS WILL HAVE DIRECT BEARING ON WHETHER
WESTERN HALF OF CWA OR EASTERN HALF OF CWA SEES MOST RAIN ON MONDAY.
TOUGH TO TELL AT THIS POINT WHICH IDEA WILL BE CORRECT. CORFIDI
VECTORS...BOTH FORWARD AND BACKWARD PROPAGATING...ARE ORIENTED
GENERALLY FROM WEST TO EAST ALONG AND SOUTH OF UPR MICHIGAN...WHICH
LIKELY WILL KEEP PERIODS OF PERSISTENT/HEAVIEST SHRA/TSRA TO SOUTH
OF THE AREA SINCE THAT IS WHERE PRIME GENESIS REGION FOR SHRA/TSRA
WILL BE ALONG THE SFC WARM FRONT. PERFER THE LOOK OF THE ECMWF/UKMET
WHICH KEEP THE TRACK OF HIGHEST QPF ONLY OVER SCNTRL CWA...WITH
LIGHTER AMOUNTS FARTHER NORTH AWAY FM THE SFC WARM FRONT. EVEN
SO...GOING LIKELY POPS SEEM ON TRACK WITH H85 FRONT IN VICINTY.
KEPT SMALL MENTION OF TSRA MAINLY OVER SOUTH HALF INTO THE EASTERN
CWA ALONG NORTH GRADIENT OF ELEVATED INSTABILITY. SPC DAY2 SEVERE
RISK KEEPS SLIGHT PROBABILITIES FARTHER SOUTH...BUT DOES HIGHLIGHT
SOUTHERN TIER OF CWA FOR A 5 PCT RISK.
NEXT SURGE OF SHRA/TSRA DEVELOP MONDAY NIGHT IN RESPONSE TO
SHARPENING TROUGH ALOFT. SFC LOW HAS TRENDED FARTHER NORTH OVER TIME
WITH SFC LOW LIFTING ACROSS WESTERN LK SUPERIOR BY TUESDAY MORNING.
BEFORE THAT...LARGE SCALE ASCENT DEVELOPS DUE TO THE DEEPENING OF
TROUGH ALOFT AND INCREASINGLY DIFFLUENT FLOW ALOFT. THOUGH SFC WARM
FRONT STAYS MAINLY SOUTH OF UPR MICHIGAN...H85 WARM FRONT WILL
PROVIDE MAIN FOCUS FOR SHRA/TSRA MONDAY NIGHT INTO TUESDAY MORNING
AS ANOTHER SURGE OF H85-H7 MOISTURE ADVECTION INTERSECTS THE
BOUNDARY. GFS SEEMS TOO QUICK IN SLIDING THIS WHOLE SYSTEM TO THE
EAST. ECMWF/UKMET AND GEM-NH ARE SLOWER WHICH MAKES SENSE WITH THE
SHARPER TROUGH ALOFT. GIVEN PWATS STILL OVER 200 PCT OF
NORMAL...MODERATE TO HEAVY RAIN COULD OCCUR. DECENT SIGNAL FROM
PREFERRED MODELS THAT HEAVIEST RAIN IMPACTS MAINLY NORTHERN
CWA...INCLUDING THE KEWEENAW PENINSULA. OBVIOUSLY WITH THE SNOWMELT
AND HIGHER RIVER FLOWS THAT ARE CURRENTLY OCCURRING THIS WOULD NOT BE
A GOOD SITUATION IF IT WORKED OUT THIS WAY. SIMILAR TO FORECAST ON
MONDAY...SINCE THE SFC WARM FRONT IS STILL SOUTH OF THE AREA...SFC
SHRA/TSRA ONGOING ALONG THE FRONT COULD VERY WELL IMPACT THIS ENTIRE
SCENARIO...ESPECIALLY AS STORM MOTIONS ARE FORECAST TO BE FROM SW-
NE...SUGGESTING THAT IF CLUSTER OF STORMS FORM FARTHER SOUTH CLOSER
TO SFC WARM FRONT THEY COULD GLIDE OVER EASTERN CWA AND GENERALLY
BYPASS THE WESTERN CWA. CONDIFENCE IN ANY OF THESE TYPE OF DETAILS
REMAINS LOW ATTM.
AS THE SFC LOW LIFTS NORTH OF LK SUPERIOR BY TUESDAY AFTN...EXPECT
DRYING TO SPREAD IN FROM THE WEST...DIMINISHING THEN SHUTTING OFF
ADDITIONAL PRECIPITATION. THOUGH SKIES WILL NOT COMPLETELY CLEAR OUT
AS A LOT OF H85 MOISTURE REMAINS...EVEN SHALLOW MIXING WITH THE WEST
LOW-LEVEL WINDS SHOULD RESULT IN TEMPS PUSHING INTO THE 60S OVER ALL
BUT THE FAR WEST/NORTHWEST AND EAST CWA.
QUESTION FOR THE REST OF THE WEEK IS NOT IF IT WILL BE COOL AND
UNSETTLED BUT TO WHAT DEGREE. ECMWF IS BACK TO SHOWING A VERY DEEP
TROUGH ALOFT THURSDAY INTO FRIDAY...EVEN TO THE POINT OF BECOMING
CLOSED OFF AROUND THURSDAY. PREVIOUS RUNS OF ECMWF HAD BACKED AWAY
FM STRONGER WAVE WRAPPING AROUND THE EDGE OF THE TROUGH LATE THIS
WEEK BUT NOW ITS BACK. GIVEN H85 TEMPS -2C TO -4C FALLING TO BLO -6C
AS THIS WAVE LIFTS OVER THE REGION...CERTAINLY POSSIBLE THAT SOME
SNOW COULD OCCUR THURSDAY INTO FRIDAY FOR ALMOSTL ANYWHERE IN THE
CWA. CONSENSUS OF THAT WRAPPED UP ECMWF SOLUTION ALONG WITH OTHER
AVAILABLE MEDIUM RANGE MODELS RESULTED IN LOW CHANCES ATTM...WITH
MOST MENTION OF SNOW ONLY OCCURRING LATER AT NIGHT INTO THE MORNING
BEFORE BLYR WARMS ENOUGH FOR JUST RAIN. SYSTEM WILL BE SOMETHING TO
KEEP EYE ON AS WE GET LATER INTO THE WEEK. AT THE LEAST EVEN IF WE
GET BY WITHOUT SEEING ANY SNOW...TEMPS WILL FALL TO WELL BELOW
NORMAL VALUES AGAIN. HIGHS MID-LATE WEEK LIKELY WILL STAY IN THE 40S
OVER MUCH OF NORTHERN UPR MICHIGAN CLOSER TO LK SUPERIOR AND ONLY IN
THE 50S OVER SOUTHERN CWA. NIGHTTIME LOWS WILL BE AROUND FREEZING
FOR MUCH OF THE CWA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 139 AM EDT SUN MAY 11 2014
HIGH PRES WILL MOVE SHIFT AWAY FROM THE AREA AS A WARM FRONT
DEVELOPS OVER IOWA AND NRN IL TODAY. EXPECT AN INCREASE IN MID AND
HIGH CLOUDS OVER UPPER MI ALONG WITH SOME LIGHT SHOWERS OR SPRINKLES
AROUND IWD. HOWEVER...WITH THE VERY DRY LOW LEVEL AIRMASS IN
PLACE...EXPECT VFR CONDITIONS TO PREVAIL THROUGH THE FCST PERIOD EVEN
WITH ANY LIGHT PCPN.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 454 AM EDT SUN MAY 11 2014
WINDS LESS THAN 20 KTS THROUGH THIS EVENING. WINDS BEGIN TO INCREASE
OVER WESTERN PORTIONS OF LK SUPERIOR LATE TONIGHT AND MORE SO ON
MONDAY AS LOW PRESSURE APPROACHES FROM THE SOUTHWEST. FREQUENT GALE
GUSTS APPEAR LIKELY OVER FAR WEST...SO HAVE ISSUED A GALE WATCH.
WINDS OVER THE REST OF THE LAKE WILL STAY AT OR BLO 30 KTS. WINDS
DIMINISH LATER MONDAY NIGHT AND THEN SWITCH TO THE WEST TO 20-25 KTS
ON TUESDAY. LOW SLOWLY SLIDES TO THE NORTHEAST OF LK SUPERIOR REST
OF THE WEEK...RESULTING IN NORTHWEST WINDS MAINLY STAYING BLO 20 KTS.
&&
.HYDROLOGY...
ISSUED AT 454 AM EDT SUN MAY 11 2014
HIGHS MOSTLY IN THE 60S TODAY WILL RESULT IN ADDITIONAL SNOWMELT
OVER HIGHER TERRAIN OF NORTHERN UPR MICHIGAN. MINIMAL RAIN AMOUNTS
ARE EXPECTED THROUGH MUCH OF TONIGHT...BUT THEN RAIN CHANCES INCREASE
MONDAY/MONDAY NIGHT AND INTO TUESDAY MORNING. THERE IS A POTENTIAL
FOR MODERATE TO HEAVY RAIN OVER THE AREAS THAT ARE STILL MELTING
SNOW...SO THE RECENT HIGHER RIVER LEVELS WILL CONTINUE THROUGH MUCH
OF THE UPCOMING WEEK. THE FLOOD WARNING CONTINUES FOR THE STURGEON
RIVER NEAR CHASSELL...WHILE ADVISORIES ARE IN PLACE FOR THE STURGEON
RIVER NEAR ALSTON...AND THE MICHIGAMME RIVER NEAR WITCH LAKE AND
ALSO NEAR REPUBLIC. IF HEAVIER RAINS MATERIALIZE EARLY THIS WEEK...
ADDITIONAL ADVISORIES AND WARNINGS MAY BE NEEDED. THOSE LIVING NEAR
RIVERS...CREEKS...AND STREAMS SHOULD CONTINUE TO MONITOR THE LATEST
RIVER LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WATCH FROM MONDAY MORNING THROUGH MONDAY EVENING FOR LSZ162.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...JLB
MARINE...JLA
HYDROLOGY...JLA
AREA FORECAST DISCUSSION
NWS JACKSON MS
444 AM CDT SUN MAY 11 2014
.TODAY THROUGH MONDAY NIGHT...
THE ARKLAMISS REGION WILL REMAIN IN A WARM/HUMID AND MAINLY DIURNAL
CONVECTIVE REGIME WITH PRONOUNCED SOUTHERLY LOW LEVEL FLOW. LARGER
SCALE FEATURES AIDING IN DEVELOPMENT OF CONVECTIVE PRECIPITATION ARE
SUBTLE...WITH THE EXIT REGION OF THE SUBTROPICAL JET HELPING TO
ENHANCE UPPER LEVEL DIVERGENCE AND PROVIDE SOME SUPPORT.
EXPECT DAYTIME HEATING TO BE A PRIMARY KEY IN SHOWER/TSTM DEVELOPMENT
LATER TODAY --- THE LATEST HRRR FORECASTS SFC BASED CAPE TO EXCEED
3000 J/KG LATER THIS AFTERNOON IN THE ARKLAMISS DELTA REGION WITH
PRECIPITABLE WATER ~ 1.75 INCHES. WITH LITTLE IN THE WAY OF
CONVECTIVE INHIBITION...ISOLATED TO SCATTERED SHOWER/TSTMS SHOULD
INCREASE IN COVERAGE PER LATEST NEAR TERM GUIDANCE BY AROUND NOON.
RELATIVELY STRONG LOW-LEVEL FLOW MAY SUPPORT STRONG WIND GUSTS IN THE
MORE INTENSE STORMS...BUT NOT EXPECTING MUCH IN THE WAY OF STORM
ORGANIZATION. CONVECTION WILL WANE FAIRLY QUICK AFTER SUNSET WITH
LOSS OF HEATING.
EXPECT A SIMILAR CONVECTIVE SET-UP FOR MONDAY WITH HEATING OF A
WARM/HUMID AIRMASS SUPPORTING ANOTHER ROUND OF MAINLY AFTERNOON
SHOWER/THUNDERSTORMS. SUBTROPICAL JET POSITIONING AND ASSOCIATED
UPPER LEVEL JET DIVERGENCE SHOULD BE A LITTLE BETTER AND SUPPORTIVE
OF GOING WITH HIGHER PRECIP CHANCES OFFERED BY GUIDANCE.
OTHERWISE...RAIN CHANCES SHOULD BE ON THE INCREASE LATE MONDAY NIGHT
IN THE DELTA REGION AS A COLD FRONT BEGINS TO APPROACH FROM THE
NORTHWEST. /EC/
TUESDAY THROUGH NEXT SUNDAY
A COLD FRONT AND ASSOCIATED BAND OF SHOWERS/TSTMS WEDNESDAY WILL
BE MAIN FOCUS THIS PERIOD WITH BELOW NORMAL TEMPERATURES EXPECTED
WED-THURS AND A WARMING TREND FRI-SUN WITH OVERALL DRIER CONDITIONS.
MODEL SUITE FOR THE MEDIUM RANGE CONTINUES TO ALIGN INDICATING AN
AMPLIFIED ERN CONUS RIDGE WITH A DEEP TROUGH ACROSS THE CENTRAL
CONUS AND ATTENDANT SFC LOW IN THE NORTHERN MS VALLEY HELPING SHIFT
AN ELONGATED FRONTAL AXIS TOWARDS AND THROUGH THE LOWER MS VALLEY BY
MID WEEK. THE SLOWER TIMING OF WEATHER ELEMENTS IMPLEMENTED
YESTERDAY LOOKS ON TRACK AS EC REMAINS CONSISTENT WITH CONTINUED
SUPPORT FROM GEM/UKMET WHILE GFS HAS CONTINUED TO SLOW TOWARDS THIS
CAMP.
HAVE INCREASED POPS TUESDAY OVER PREVIOUS VALUES AS A LEAD S/WV
AHEAD OF THE MAIN TROUGH AXIS IS BECOMING MORE REALIZED ALONG THE
FRONTAL AXIS POSITIONED FROM A PADUCAH KY TO MEMPHIS TN TO LAKE
CHARLES LA LINE. GREATEST RAIN CHANCES WILL BE IN W/NW TUESDAY AS
THIS WAVE MOVES OVER THE REGION WHILST SURFACE CONVERGENCE AIDS AS A
LOW-LVL FOCUS. FARTHER EAST, INSTABILITY SHOULD BUILD AND ALLOW FOR
SOME DIURNALLY DRIVEN ISO/SCT TSTMS. THIS ACTIVITY SHOULD WANE
THROUGH TUES EVE WHILE SHOWERS CONTINUE ALONG BOUNDARY IN W/NW AREAS
IN CONJUNCTION OF HIGHER MOISTURE INFLUX/LIFT.
ATTM...HEAVIEST PRECIP AXIS LOOKS TO REMAIN TO OUR NW INTO AR BUT
WILL NEED TO MONITOR FOR NW/W DELTA LATE TUESDAY INTO WEDNESDAY FOR
FLASH FLOODING POTENTIAL BUT CONFIDENCE IS LOW WITH LACK OF DEEPER
FORCING AND NON-COINCIDING HIGH MOISTURE INFLUX. EC/GFS MODERATELY
AGREE THAT FRONT WILL BEGIN TO MOVE THROUGH AREA WED MORNING TO MID
DAY WHILE GREATER QG FORCING MAGNITUDES PIVOT OVER THE REGION ALONG
AND BEHIND THE FRONT WITH INSTABILITY BUILDING IN EAST MS AND INTO AL
WED AFTN. HAVE PLACED GREATEST POPS WED MRNG THROUGH THE EVENING. IF
CURRENT TIMING HOLDS, STRONG/SEVERE DOES NOT LOOK LIKELY FROM LACK OF
FULL DESTABILIZATION AND LACKLUSTER THERMO ENVIRONMENT. TEMPS SHOULD
BE HELD IN CHECK WEDNESDAY BEHIND FRONT AND WITH STRATIFORM
ANAFRONTAL RAIN WITH HIGHS IN THE LOW TO MID 70S. THESE VALUES WERE
CUT FROM MEXMOS BUT FURTHER CUTS MAY NEEDED.
RAIN/TSTMS SHOULD CLEAR OUT BY THURSDAY MORNING ALONG WITH CLOUDS
THROUGH THE DAY BUT TEMPS WILL BE BELOW NORMAL AS AREAS DIP INTO THE
UPPER 40S THURS MORNING WHILE RECOVERING INTO THE MID 70S THAT AFTN.
NW FLOW WILL CONTINUE FRI-SUN WITH OVERALL DRIER CONDITIONS
EXPECTED. HOWEVER, DESPITE AREA UNDER NW FLOW, ENOUGH MOISTURE AND
SOME DESTABILIZATION WITH SUBTLE WAVES MOVING THROUGH COULD TRIGGER
SOME SHOWER ACTIVITY IN THE NORTH BUT CONFIDENCE TO LOW TO PLACE
WEATHER WORDING IN AT THIS TIME. /ALLEN/
&&
.AVIATION...PERSISTENT SOUTHERLY FLOW WILL CONTINUE A PATTERN OF LATE
NIGHT AND EARLY MORNING LOW STRATUS/FOG. CIGS/VSBYS WILL BE ERRATIC
AND MAY BOUNCE OFTEN BETWEEN MVFR AND LIFR CATEGORIES...WITH MOST
CONSISTENTLY POOR CONDITIONS IN THE HBG/PIB/JAN/HKS/MEI/NMM/GTR/CBM
AREAS. EXPECT CIGS TO LIFT AND VSBYS IMPROVE MID/LATE MORNING WITH
HEATING...BUT INCREASING INSTABILITY WILL LEAD TO SCATTERED MAINLY
AFTERNOON SHRA/TSRA. THIS PATTERN OF MORNING LOW CLOUDS AND AFTERNOON
CONVECTION SHOULD GENERALLY REPEAT ITSELF MONDAY. /EC/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 86 68 85 67 / 23 20 34 17
MERIDIAN 87 65 87 62 / 20 18 31 12
VICKSBURG 87 70 87 68 / 30 20 48 29
HATTIESBURG 87 68 88 65 / 43 17 29 12
NATCHEZ 85 69 85 68 / 43 18 56 26
GREENVILLE 87 69 84 67 / 28 20 54 43
GREENWOOD 87 69 86 68 / 20 20 50 29
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
EC/ALLEN
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
406 AM EDT SUN MAY 11 2014
.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL MAINTAIN ABOVE NORMAL TEMPERATURES
THROUGH THE MIDDLE OF THE WEEK. A COLD FRONT WILL APPROACH FROM
THE WEST ON THURSDAY...CROSSING THE AREA BY FRIDAY. COOLER
TEMPERATURES WILL FOLLOW FOR NEXT WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 4 AM SUNDAY...ONBOARD VAPOR SENSORS FROM SPACE SHOW A PLUME
OF ELEVATED PRECIPITABLE WATER DRAWING NE INTO SC AHEAD OF AN
APPROACHING BUT DECAYING FRONTAL SYSTEM EARLY THIS MORNING. MOSAIC
RADAR ANIMATIONS ARE PICKING UP ISOLATED RETURNS OVER THE EASTERN
1/3RD OF SC AND VERY SE NC...AND THIS ACTIVITY APPEARS TO BE
LINKED WITH A DISTURBANCE ALOFT TRACKING OVERHEAD OF COLUMBIA SC
CURRENTLY. SURFACE ANALYSIS SHOWS A FRONTAL BOUNDARY OVER THE MID-
ATLANTIC...WITH LITTLE IDENTITY SEEN INTO THE CAROLINAS.
TIME-HEIGHT ANALYSIS SHOWS READILY AVAILABLE MOISTURE MUCH OF THE
DAY THROUGH ABOUT 15 KFT. FORECAST SOUNDINGS DEPICT A WEAKLY
FORCED BUT MODERATELY UNSTABLE AIR-MASS TODAY. SURFACE HEATING
THIS AFTERNOON WILL INTERACT WITH PWAT VALUES AROUND 1.5". RECENT
SATELLITE TRENDS SUGGEST DIFFERENTIAL HEATING THROUGH MORNING MAY
ALSO PLAY A ROLE IN TRIGGERING CONVECTION LATER TODAY. SURFACE
OUTFLOWS IN THE RELATIVELY MOIST AIR-MASS WILL ALSO FAVOR MORE
INITIATION. CONVECTIVE MODE OBSERVATIONS SO FAR SHOW PULSE AND LOW
TOP SHOWERS CONGRUENT WITH HIGH PWAT LOW BULK-SHEAR REGIMES.
LOSS OF DIURNAL HEATING AND EXITING IMPULSES ALOFT WILL BRING A
DIMINISHING TREND IN CONVECTION BY LATE EVENING. MINIMUM TEMPS
INTO EARLY MONDAY MIDDLE 60S INLAND TO UPPER 60S NEAR THE COAST.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 330 AM SUNDAY...MID TO UPPER RIDGE WILL BE BUILDING BACK UP
THROUGH THE SOUTHEAST AS BERMUDA HIGH CONTINUES TO PRODUCE A
MOIST SOUTHWESTERLY RETURN FLOW EARLY TO MID WEEK. GRADIENT
REMAINS FAIRLY WEAK THROUGH THE PERIOD WHICH SHOULD ALLOW SEA/LAND
BREEZE TO DOMINATE. ALTHOUGH CONVERGENCE ALONG THE SEABREEZE
SHOULD PRODUCE SOME CU DEVELOPMENT...THERE SHOULD BE ENOUGH DRY AIR AND
SUBSIDENCE ALOFT TO LIMIT SHOWER ACTIVITY. CAN NOT COMPLETELY RULE
OUT AN ISOLATED SHWR OR TWO...BUT WILL MOST LIKELY KEEP POPS
SILENT. MOISTURE PROFILES ALSO CONTINUE TO SHOW UPPER LEVEL
MOISTURE AND THEREFORE MAY SEE SOME CIRRUS STREAMING ACROSS THE
AREA IN WESTERLY FLOW ABOVE H40.
AS FOR TEMPS...THE DECENT RIDGE ALOFT WILL KEEP H5 HEIGHTS AROUND
588 DEM. MAY SEE A SOME CLOUDS BLOCKING THE SUN AT TIMES BUT
OVERALL EXPECT WARM START TO EACH DAY WITH OVERNIGHT TEMPS
REMAINING CLOSER TO 70...LEADING TO TEMPS WELL INTO THE 80S MOST
PLACES WITH STRONGER MAY SUNSHINE.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 330 AM SUNDAY...MID TO UPPER RIDGE REMAINS AMPLIFIED UP
THE EAST COAST AS TROUGH DIGS THROUGH THE MISSISSIPPI VALLEY
WEDNESDAY. SFC HIGH MOVING OFF THE NEW ENGLAND COAST BEGINS TO
DOMINATE WITH MORE OF NORTH TO SOUTH ELONGATED HIGH PRESSURE
SYSTEM DOWN INTO THE CARIBBEAN. THIS WILL HELP THE WINDS BACK TO A
MORE S-SE FLOW. THE DEEPENING MID TO UPPER TROUGH WILL PUSH
EASTWARD DISPLACING THE RIDGE EAST AND PUSHING A COLD FRONT EAST
INTO THE CAROLINAS ON THURS. AT THE SAME TIME AN IMPULSE WILL RIDE
UP AROUND THE ATLANTIC RIDGE FROM THE BAHAMAS AND MAY ADD TO THE
OVERALL MOISTURE REACHING INTO THE CAROLINAS ON THURS. EXPECT
CONVECTION DEVELOPMENT ALONG AN AHEAD OF THIS COLD FRONT AS IT
MOVES EASTWARD REACHING THE COAST THURS NIGHT INTO FRI MORNING.
WILL CONTINUE WITH MAIN FOCUS OF CONVECTION ON THURS INTO THURS
NIGHT.
ONCE THE FRONT MOVES THROUGH BY FRIDAY DRIER AND COOLER AIR WILL
MOVE IN WITH 850 TEMPS DROPPING FROM AROUND 15 C WED AFTN DOWN TO
ABOUT 5 C BY SAT MORNING. H5 HEIGHTS WILL DROP AROUND 20 DEM BY
SAT MORNING. OVERALL EXPECT COOLER WEATHER HEADING INTO NEXT
WEEKEND. TEMPS WILL RUN SEVERAL DEGREES ABOVE NORMAL TO START
REACHING WELL INTO THE 80S ON WED. THE DEWPOINT TEMPS WILL BE IN
THE MID 60S AHEAD OF THE FRONT BUT WILL DROP INTO THE 40S BY THE
WEEKEND WITH TEMPS SEVERAL DEGREES BELOW NORMAL. EXPECT HIGH TEMPS
ONLY IN THE LOWER TO MID 70S FOR THE WEEKEND.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AS OF 06Z...RADAR IMAGERY SHOWS SOME SHOWERS OVER SOUTH CAROLINA
ASSOCIATED WITH AN UPPER DISTURBANCE. THE LATEST HRRR RUNS DISSIPATE
MUCH OF THIS ACTIVITY BEFORE IT REACHES NC. PERIODS OF MVFR/IFR
CIGS/VSBYS IN THE EARLY MORNING HOURS...AS THIS MOIST LOW LEVEL
ENVIRONMENT HAS PROVEN TO BE CONDUCIVE FOR FOG/STRATUS. GUIDANCE
FAVORS IFR STRATUS AND REDUCED VSBYS AT KFLO/KLBT. TEMPO IFR
CIGS/VSBYS CANNOT BE RULED OUT ALONG THE COAST AS WELL. ISOLATED
CONVECTION IS POSSIBLE LATER TODAY WITH SURFACE HEATING AS THE LOW
LEVELS MOISTEN. THE SEA BREEZE WOULD LIKELY BE THE FOCUS FOR ANY
SHOWER ACTIVITY...WITH THE BEST CHANCES AT THE INLAND TERMINALS
LATER THIS AFTERNOON. WILL MAINTAIN VCSH ATTM SINCE COVERAGE WILL
BE SPOTTY AT BEST. SOUTHWEST WINDS 5-10 KTS WILL BECOME SOUTH
AROUND 10 KTS IN THE AFTERNOON AS THE SEA BREEZE PUSHES INLAND.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 4 AM SUNDAY...MANAGEABLE MARINE CONDITIONS EXPECTED TODAY AS
A WEAK COLD FRONT N AND W OF THE WATERS DISSIPATES. THIS WILL
LEAVE A LIGHT SW WIND FLOW ACROSS THE WATERS THROUGH TONIGHT. SEAS
GENERALLY 2-3 FEET...IN A MIX OF SSW WAVES 1-2 FEET EVERY 4-5 SEC
AND SE WAVES 1-2 FT EVERY 7-8 SECONDS. ISOLATED TSTMS ARE POSSIBLE
NEAR SHORE THIS AFTERNOON INTO THIS EVENING...AND THE MOTION WILL BE
FROM SW TO NE.
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 330 AM SUNDAY...SOUTHERLY FLOW AROUND BERMUDA HIGH WILL
CONTINUE THROUGH EARLY NEXT WEEK. EXPECT S-SW WINDS 10-15 KTS
THROUGH THE PERIOD...WITH LITTLE FLUCTUATION IN STRENGTH OR
DIRECTION EITHER DAY. THESE WINDS PLUS THE PERSISTENT FETCH AROUND
THE OFFSHORE HIGH PRESSURE WILL CREATE 2-3 FT SEAS EACH DAY...WITH
A WAVE SPECTRUM COMPRISED OF A SOUTHERLY 4-5 SEC WIND WAVE AND A
LOW-AMPLITUDE SE GROUND SWELL.
LONG TERM /WEDNESDAY THROUGH THURSDAY/...
AS OF 330 AM SUNDAY...HIGH PRESSURE BECOMES MORE ORIENTED NORTH TO
SOUTH FROM THE WATERS OFF OF NEW ENGLAND COAST DOWN TO THE LOCAL
WATERS OFF THE SOUTHEAST COAST THROUGH MID WEEK. THE FLOW AROUND
THE HIGH WILL REMAIN ORIENTED NORTH TO SOUTH WITH WINDS S-SE TO
START AROUND 10 TO 15 KTS. BY THURSDAY...GRADIENT TIGHTENS AS
DIGGING MID TO UPPER TROUGH PUSHES A COLD FRONT EAST INTO THE
CAROLINAS. THIS WILL PRODUCE AN INCREASE IN WINDS UP AROUND 15
KTS. IN TURN...YOU CAN EXPECT AN INCREASE IN SEAS UP FROM AROUND 2
TO 3 FT EARLY WED TO 3 TO 4 FT BY THURS NIGHT. BEST SHOT OF
SHOWERS AND THUNDERSTORMS WILL COME LATE THURS ASSOCIATED WITH
COLD FRONT.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...MJC
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...MJC/BJR
AREA FORECAST DISCUSSION
NWS RALEIGH NC
300 AM EDT SUN MAY 11 2014
.SYNOPSIS... BERMUDA HIGH PRESSURE OVER THE ATLANTIC WILL EXTEND
WEST OVER THE REGION THROUGH TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 AM SUNDAY...
THE LATEST SURFACE ANALYSIS SHOWED WEAK HIGH PRESSURE OVER CENTRAL
NORTH CAROLINA WITH THE AREA ESSENTIALL PRECIPITATION-FREE AS MID-
LEVEL CLOUDS WERE CLEARING TOWARD THE SOUTHEAST. THINNING HIGH
CLOUDS FROM DEEP CONVECTION WELL UPSTREAM WERE DRIFTING IN FROM THE
NORTHWEST...AND A FEW OF THESE WILL BE NOTICED DURING THE DAY. THE
PRIMARY WEATHER CONCERN FOR TODAY IS THE POTENTIAL FOR ISOLATED TO
SCATTERED DEEP CONVECTION OVER THE FAR SOUTHEAST PART OF CENTRAL
NORTH CAROLINA THIS AFTERNOON INTO THIS EVENING.
THE GFS...NAM...AND RAP ARE DEFINITELY VERY SIMILAR IN THEIR
DEPICTION OF QPF OVER CENTRAL NORTH CAROLINA THIS AFTERNOON INTO THE
EARLY EVENING...WITH THE MEASURABLE LINE MAINLY ALONG AND SOUTH OF A
LINE FROM ABOUT WADESBORO TO TARBORO. IT IS IN THAT AREA WHERE THE
GREATEST PRECIPITABLE WATER VALUES ARE FORECAST THIS AFTERNOON ON
THE GFS AND NAM...TO ABOUT 1.5 INCHES...AND WHERE THERE IS MODEST
LIFT...850MB CONVERGENCE...AND WEAK UPPER DIFFLUENCE. MLCAPE IN THE
LOWEST KM IS FORECAST AROUND 500J/KG...WITH LIFTED INDICES A COUPLE
OF DEGREES OR SO BELOW 0C. BUFR SOUNDINGS AT KGSO...KRDU...AND KRWI
ARE BASICALLY STABLE TO DEEP CONVECTION...BUT THE KFAY BUFR SOUNDING
IS MORE UNSTABLE WITH A MORE LIMITED CAP. CONVECTIVE-ALLOWING MODELS
SUCH AS THE HRRR WRF SUGGESTS ISOLATED-TO-SCATTERED SHOWERS AND
POSSIBLY A THUNDERSTORM DEVELOPING EARLY THIS AFTERNOON AND THEN
WANING WITH SUNSET. LIGHT WIND FIELDS SHOULD MAKE FOR FAIRLY
UNORGANIZED CONVECTION...AND 1000-500MB LAPSE RATES...ONLY TO ABOUT
6C/KM...AND DOWNDRAFT CAPE THAT IS FORECAST BELOW 500J/KG SHOULD
MAKE FOR LIMITED STRONG STORM POTENTIAL.
WILL LEAN TOWARD THE WARMER MAV MOS GUIDANCE ESPECIALLY SINCE IN
MOST PLACES IT IS EXPECTED THAT...EVEN WITH LIGHT WINDS...SUFFICIENT
MIXING SHOULD OCCUR TO MIX OUT DEW POINTS SOME. ALREADY IN PARTS OF
THE NORTHWEST PIEDMONT TO THE TRIANGLE...DEW POINTS HAVE FALLEN
BELOW 60F. HIGHS TODAY 85 TO 90.
TONIGHT...CLEAR TO PARTLY CLOUDY WITH THE POTENTIAL FOR SOME LOW
CLOUDS OR MORE LIKELY FOG IN THE LIGHT WIND FIELD LATE PARTICULARLY
WHERE ANY SHOWERS OCCUR. THE BEST POTENTIAL FOR THESE SHOULD BE
TOWARD THE SOUTHEAST WHERE SREF PROBABILITIES OF FOG ARE HIGHEST
RELATIVE TO THE REST OF CENTRAL NORTH CAROLINA. WILL NOTE PATCHY FOG
IN THE GRIDDED AND WORDED FORECASTS THERE. OVERNIGHT LOWS AROUND 60
TO THE MID 60S.
&&
.SHORT TERM /MONDAY AND MONDAY NIGHT/...
AS OF 300 AM SUNDAY...
SIMILAR CONDITIONS TO TODAY...SUNDAY...ARE EXPECTED MONDAY AND
MONDAY NIGHT WITH HIGHER PRECIPITABLE WATER VALUES CONTINUING OVER
ABOUT THE SOUTHERN TWO TIERS OF COUNTIES IN CENTRAL NORTH
CAROLINA...BETTER LIFT FORECAST IN THE AFTERNOON AND EARLY
EVENING...AND GREATER INSTABILITY COMPARED TO THE REST OF THE AREA.
IN FACT...THE GFS AND NAM MODELS BOTH FORECAST A SLIGHT INCREASE IN
INSTABILITY IN THE SANDHILLS AND SOUTHERN COASTAL PLAIN MONDAY...
WITH LIFTED INDICES APPROACHING -5C IN THE AFTERNOON AND MLCAPE IN
THE LOWEST KM AS HIGH AS JUST OVER 1000J/KG. DOWNDRAFT CAPE IS ALSO
GREATER ON THE GFS WITH SLIGHTLY BETTER 1000-500MB LAPSE RATES...
CLOSER TO 6.5C/KM. THE BUFR SOUNDING FROM THE NAM TOWARD KFAY IS
MORE UNSTABLE MONDAY COMPARED TO SUNDAY...WHILE THE GFS BUFR
SOUNDING HAS JUST A SLIGHTLY BETTER CAP BETWEEN 700MB AND 850MB.
GUIDANCE POPS AND QPF ARE ONCE AGAIN VERY SIMILAR ON THE NAM AND THE
GFS...AND WILL NOTE THE POTENTIAL FOR ISOLATED-TO-SCATTERED
AFTERNOON AND EARLY EVENING SHOWERS AND THUNDERSTORMS IN AN AREA
VERY SIMILAR TO THAT FORECAST TODAY...EXCEPT EXPANDED WEST AND NORTH
EVER SO SLIGHTLY. BUFR SOUNDINGS TOWARD THE TRIAD AND KRDU STILL
SEEM A LITTLE TOO STABLE FOR DEEP CONVECTION. WILL CURRENTLY REFRAIN
FROM THE MENTION OF ANY STRONG STORMS FOR NOW IN THE HWO SO AS TO
MONITOR INSTABILITY AND MOISTURE TRENDS...AND AS ANY DEEP CONVECTION
SHOULD STILL BE FAIRLY UNORGANIZED.
1000-850MB THICKNESSES ARE WARMER MONDAY COMPARED TO TODAY AS
HEIGHTS ALOFT RISE...ENOUGH FOR HIGHS ABOUT TWO OR THREE DEGREES
WARMER MONDAY. OVERNIGHT MONDAY...WILL AGAIN NOTE THE POTENTIAL FOR
PATCHY FOG LATE...MAINLY SOUTH...IN A CONTINUED FAIRLY LIGHT WIND
FIELD. THIS IS SIMILAR TO THE SREF ORIENTATION OF LOW VISIBILITY
PROBABILITIES IN CENTRAL NORTH CAROLINA LATE MONDAY NIGHT. LOWS
MONDAY NIGHT MOSTLY LOWER TO MID 60S.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 300 AM SUNDAY...
TUESDAY AND WEDNESDAY: THIS PERIOD WILL START WITH RIDGING ALOFT AND
A BERMUDA HIGH OFF THE COAST...RESULTING IN WARM MOIST RETURN FLOW
INTO THE AREA. THE APPROACHING COLD FRONT WILL HELP PUSH THE RIDGE
OUT OF THE AREA LATE WEDNESDAY...WITH CONTINUED SOUTHERLY FLOW. THE
INCREASING TEMPERATURES AND MOISTURE WILL RESULT IN THE CHANCE FOR
MAINLY SCATTERED DIURNAL SHOWERS AND STORMS TO DEVELOP...ALTHOUGH
WITH THE LACK OF UPPER LEVEL FORCING...THE CHANCE OF SEVERE STORMS
CONTINUES TO BE LOW. OTHERWISE...EXPECT MAINLY DRY CONDITIONS. HIGHS
GREATEST ON TUESDAY...UPPER 80S TO AROUND 90 DEGREES...DECREASING
SLIGHTLY FOR WEDNESDAY...IN THE MID TO UPPER 80S. OVERNIGHT LOWS IN
THE MID 60S.
WEDNESDAY NIGHT THROUGH SATURDAY: THOUGH THERE ARE STILL TIMING
DIFFERENCES BETWEEN THE MODELS WITH THE APPROACHING LOW PRESSURE
SYSTEM AND ASSOCIATED COLD FRONT...THEY HAVE COME INTO BETTER
AGREEMENT OVER THE PAST FEW MODEL RUNS. THE LATEST MODEL RUNS
INDICATE THE BEST CHANCES FOR SHOWERS AND STORMS ON THURSDAY AFT/EVE
AS THE FRONT BEGINS PUSHING THROUGH THE AREA. CONFIDENCE IS
GRADUALLY INCREASING. EXPECT THE SHEAR AND INSTABILITY TO INCREASE
AS THE FRONT APPROACHES...AND WITH THE FORCING PRESENT...THE THREAT
FOR STRONG TO SEVERE STORMS EXISTS...WITH THE BEST POTENTIAL
INDICATED IN THE SANDHILLS AND COASTAL PLAIN. THERE IS STILL SOME
UNCERTAINTY REGARDING STORM INTENSITY AT THIS TIME GIVEN THE
DEPENDENCE ON FROPA TIMING AND THE MODEL DIFFERENCES IN THAT
REGARD...SO WILL CONTINUE TO MONITOR THE EVOLUTION OF THIS SYSTEM
AND WILL KEEP THE CURRENT WORDING IN THE HWO. EXPECT SHOWER AND
THUNDERSTORM CHANCES TO TAPER OFF BEHIND THE FRONT. TEMPERATURES
WILL DECREASE THROUGH THE PERIOD. HIGHS IN THE MID 70S TO LOW 80S
THURSDAY DOWN TO LOW/MID 70S SATURDAY. LOWS IN THE MID 50S TO AROUND
60 DEGREES THURSDAY NIGHT DOWN TO THE LOW TO MID 50S TO START THE
WEEKEND.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AS OF 205 AM SUNDAY...
VFR CONDITIONS WILL BE THE RULE THROUGH THE 06Z VALID TAF PERIOD.
EXPECT A FEW LOCATIONS TO EXPERIENCE MVFR CONDITIONS EARLY THIS
MORNING...WITH THE HIGHER PROBABILITIES OF SUCH CONDITIONS...
POSSIBLY EVEN IFR BRIEFLY...TOWARD THE TRIAD WHERE THE MOST RAIN
OCCURRED IN CENTRAL NORTH CAROLINA SATURDAY. DURING THIS AFTERNOON
TOWARD KFAY...TO JUST EAST OF KRWI...ANTICIPATE ISOLATED-TO-
SCATTERED SHOWERS AND A THUNDERSTORM OR TWO IN BETTER MOISTURE AND
INSTABILITY. ANY SHOWERS SHOULD DIMINISH QUICKLY WITH THE APPROACH
OF SUNSET AND THE LOSS OF DAYTIME HEATING. WHILE BOUNDARY LAYER
WINDS ARE LIGHT...BOTH THE GFS AND NAM GUIDANCE SUGGESTS SURFACE
WINDS VEERING THIS MORNING AND THEN BECOMING ABRUPTLY SOUTHERLY
OVERALL BY LATE TODAY.
BEYOND THE 06Z VALID TAF PERIOD...DURING THE WEEK THERE SHOULD BE
INCREASING PROBABILITIES EACH DAY FOR LATE NIGHT AND EARLY MORNING
LOW CLOUDS AND/OR FOG. MONDAY MORNING AND AGAIN TUESDAY MORNING IT
WOULD SEEM THE BETTER CHANCES OF SUCH WILL BE WHERE ANY AFTERNOON
SHOWERS OCCUR...SUCH AS TOWARD KFAY AND POSSIBLY KRWI. TUESDAY
THROUGH THURSDAY THE CHANCES FOR SHOWERS AND THUNDERSTORMS GRADUALLY
INCREASE AND SPREAD FROM WEST-TO-EAST ACROSS CENTRAL NORTH CAROLINA.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CBL
NEAR TERM...DJF
SHORT TERM...DJF
LONG TERM...KCP
AVIATION...DJF
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
145 AM EDT SUN MAY 11 2014
.SYNOPSIS...
HIGH PRESSURE OFFSHORE WILL MAINTAIN WARM TEMPERATURES THROUGH
THE MIDDLE OF THE UPCOMING WEEK. A CHANCE OF RAIN WILL ARRIVE LATE
IN THE WEEK AS A COLD FRONT CROSSES THE COAST ON FRIDAY. COOLER
TEMPERATURES WILL PREVAIL INTO NEXT WEEKEND IN WAKE OF THE FRONT.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
AS OF 1045 PM SATURDAY...CONVECTION UPSTREAM CONTINUES TO WANE
ESPECIALLY COMPARED TO JUST PRIOR TO SUNSET. TWO UPSTREAM 5H
VORTS IE. S/W TROFS...TO PASS IN CLOSE PROXIMITY OVERNIGHT INTO
SUNDAY. 1 REMAINS NORTH OF THE FA...TRACKING OFF THE DELMARVA
COAST BY DAYBREAK SUN. THE OTHER MOVES ACROSS THE NE GULF COAST
STATES OVERNIGHT...AND OFF THE GA COAST AFTER DAYBREAK SUNDAY. THE
BEST CONVECTION CHANCES WILL LIE ALONG AND JUST AHEAD OF THESE
MID-LEVEL FEATURES. AS FOR THE ILM CWA...CONVECTION HAS FALLEN
BELOW SLIGHT CHANCE AT THE MOMENT AND SHOULD REMAIN-SO FOR THE
REMAINDER OF THE NIGHT. SFC CONVERGENCE ZONES...IE THE SEA
BREEZE...WILL FADE AWAY FROM THE LOSS OF DAYTIME INSOLATION.
OUTFLOW BOUNDARIES FROM EARLIER CONVECTION COULD CREEP ACROSS THE
ILM CWA...HOWEVER THE BEST FORCING FOR OVERNITE CONVECTION IS
PROGGED TO REMAIN NORTH AND SOUTH OF THE FORECAST AREA. AND
FINALLY...THE FORWARD PUSH OF THE SFC COLD FRONT IS PROGGED TO
CEASE WELL BEFORE REACHING THE ILM CWA OVERNIGHT. TWEAKED THE
OVERNIGHT MIN TEMPS BY 1 TO POSSIBLY 2 DEGREES ESPECIALLY AREAS
DUE TO THE LIKELIHOOD OF MORE EXTENSIVE/DEEPER LEFTOVER CLOUDINESS
AND LOCAL WINDS STAYING ACTIVE...ESPECIALLY THE COASTAL COUNTIES.
PREVIOUS DISCUSSION.................................
AS OF 300 PM SATURDAY...ACTUAL AND MODEL SOUNDINGS SHOW VERY
DRY MID LEVELS THAT WILL CONTINUE TO INHIBIT CONVECTION THROUGH
THE DAYLIGHT HOURS AND INTO THE EVENING...ESPECIALLY AS ONE NEARS
THE COAST. FURTHER INLAND THE COLUMN IS A BIT MOISTER AND THE
ISOLATED SHOWER OR THUNDERSTORM CANNOT BE RULED OUT FOR THE
REMAINDER OF THIS AFTERNOON AND INTO THE EVENING. HAVE NOT CHANGED
THE GOING FORECAST TOO MUCH IN THIS REGARD...WITH ONLY SLIGHT
CHANCE POPS UNTIL AROUND MIDNIGHT. LATEST GUIDANCE DOES INCREASE
MOISTURE ADVECTION AFTER MIDNIGHT...BUT ALSO BEGINS TO REBUILD THE
UPPER RIDGE. ASSOCIATED SUBSIDENCE WHEN COMBINED WITH LOSS OF
HEATING MEANS THAT WE WILL STAY DRY AFTER MIDNIGHT.
GUIDANCE HAS BEEN CONSISTENTLY TOO COOL BY SEVERAL OR MORE DEGREES
FOR OUR OVERNIGHT TEMPERATURES. HAVE TAKEN THE GUIDANCE WITH THE
WARMEST FORECAST...THE NAM MOS...AND BUMPED THOSE NUMBERS UP BY A
DEGREE OR SO. THIS WILL GIVE US LOWS IN THE UPPER 60S. THIS IS A
SHADE LOWER THAN LAST NIGHT...WHICH MAKES SENSE AS ONGOING SWLY
LOW LEVEL FLOW WILL WEAKEN SOMEWHAT OVERNIGHT.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/...
AS OF 300 PM SATURDAY...SUMMER-LIKE PATTERN TO REDEVELOP AS
BERMUDA-TYPE HIGH PERSISTS OFFSHORE AND AN AMPLIFYING UPPER RIDGE
RE-ASSERTS ITSELF ACROSS THE SOUTHEAST. THESE TWO FEATURES IN
TANDEM WILL DRIVE TEMPERATURES ONCE AGAIN TO WELL ABOVE NORMAL
VALUES FOR THE EARLY PART OF THE WEEK...WITH HIGHS AROUND 90
INLAND BOTH DAYS...MID 80S AT THE COAST...AND AROUND 80 ON THE
BEACHES. MONDAY WILL BE THE WARMER OF THE TWO DAYS. LOWS BOTH
NIGHTS WILL ALSO BE WELL ABOVE NORMAL...FALLING ONLY INTO THE
MID 60S...AROUND 70 MONDAY NIGHT NEAR THE BEACHES.
THE MORE DIFFICULT PART OF THE FORECAST INVOLVES CONVECTIVE
POTENTIAL BOTH DAYS. SPC HAS A GENERAL RISK IN THE SWODY2 AND
SWODY3 OUTLOOKS FOR THE SOUTHEAST. ON SUNDAY...LOW LEVEL
MOISTURE PERSISTS BELOW 600MB INTO THE AFTN...BUT THIS OCCURS
WHILE THE RIDGE AXIS BUILDS TO THE WEST...CREATING DRYING NW FLOW
ABOVE 800MB. THIS SUGGESTS THAT HEATING OF THE DAY WHICH COULD
FUEL TSTMS...WILL BE RACING AGAINST INCREASINGLY DRY MID-LEVEL
AIR WHICH WOULD PREVENT CONVECTION. ATTM EXPECT THE SEA BREEZE
BOUNDARY WILL BE THE POTENTIAL FOCUS FOR CONVECTION ON
SUNDAY...AND WILL CARRY ONLY ISOLATED TSTMS. BY MONDAY...THE 5H
RIDGE PEAKS OVERHEAD...AND THIS SHOULD PUT A LID ON CONVECTION.
FORECAST SOUNDINGS SHOW VERY DRY AIR ABOVE 900MB...AND SURFACE
PARCELS WILL ENCOUNTER SOME CIN AS THE THERMAL RIDGE EXPANDS
OVERHEAD. FOR THIS REASON BELIEVE THERE WILL BE NO TSTMS ON
MONDAY...AND WILL KEEP POP SILENT.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 300 PM SATURDAY...MID LEVEL HIGH PRESSURE WILL DOMINATE THE
FIRST TWO DAYS OF THE FORECAST PROVIDING A CONTINUATION OF ABOVE
NORMAL TEMPERATURES AND MINIMAL CHANCES FOR CONVECTION.FOR
POPS...WILL MAINTAIN THE INLAND SEA BREEZE AREAS FOR TUESDAY AND
THE SLIGHT TRANSITION TO WESTERN COUNTIES FOR WEDNESDAY. AS THE
RIDGE FINALLY BREAKS DOWN WITH A PHASING MID LEVEL TROUGH TO THE
WEST...PRECIPITABLE WATERS AND COOLING MID LEVELS WILL MAKE
CONVECTION MORE LIKELY THURSDAY AND PART OF THE DAY FRIDAY. THE
NEW FORECAST DAY...SATURDAY LOOKS DRIER AND COOLER AS THE TROUGH
IS SUFFICIENTLY POTENT TO PUSH THE FRONT OFFSHORE. NO CHANGES TO
THE TEMPERATURE FORECAST THE PREVIOUS DAYS.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AS OF 06Z...RADAR IMAGERY SHOWS SOME SHOWERS OVER SOUTH CAROLINA
ASSOCIATED WITH AN UPPER DISTURBANCE. THE LATEST HRRR RUNS DISSIPATE
MUCH OF THIS ACTIVITY BEFORE IT REACHES NC. PERIODS OF MVFR/IFR
CIGS/VSBYS IN THE EARLY MORNING HOURS...AS THIS MOIST LOW LEVEL
ENVIRONMENT HAS PROVEN TO BE CONDUCIVE FOR FOG/STRATUS. GUIDANCE
FAVORS IFR STRATUS AND REDUCED VSBYS AT KFLO/KLBT. TEMPO IFR
CIGS/VSBYS CANNOT BE RULED OUT ALONG THE COAST AS WELL. ISOLATED
CONVECTION IS POSSIBLE LATER TODAY WITH SURFACE HEATING AS THE LOW
LEVELS MOISTEN. THE SEA BREEZE WOULD LIKELY BE THE FOCUS FOR ANY
SHOWER ACTIVITY...WITH THE BEST CHANCES AT THE INLAND TERMINALS
LATER THIS AFTERNOON. WILL MAINTAIN VCSH ATTM SINCE COVERAGE WILL
BE SPOTTY AT BEST. SOUTHWEST WINDS 5-10 KTS WILL BECOME SOUTH
AROUND 10 KTS IN THE AFTERNOON AS THE SEA BREEZE PUSHES INLAND.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1045 PM SATURDAY...SFC HIGH PRESSURE CENTERED EAST AND
OFFSHORE FROM THE CAROLINA COASTS...WILL CONTINUE TO RIDGE BACK
WESTWARD ACROSS THE AREA WATERS OVERNIGHT AND INTO THE SHORT TERM
PERIOD. THE APPROACHING AND NOW WEAK COLD FRONT DROPPING DOWN FROM
THE NW-N WILL BECOME STATIONARY AND REMAIN INLAND...AND IS
PROGGED NOT TO REACH THE ILM COASTAL WATERS AS THE RIDGING FROM
THE OFFSHORE WATERS REMAINS TOO STRONG TO BUDGE. HAVE GONE WITH
S TO SSW WINDS BECOMING SW-WSW AT 10-15 KT WITH CONTINUED GUSTS
20+...MAINLY ALONG THE NEARSHORE WATERS DUE TO THE SLOW DECAY OF
THE SEA-BREEZE CIRCULATION. SIGNIFICANT SEAS WILL BE GOVERNED BY
THE LOCALLY PRODUCED 2 TO 4 FOOT WIND DRIVEN WAVES/CHOP...
EXHIBITING 3 TO 6 SECOND PERIODS.
PREVIOUS DISCUSSION..................................
AS OF 300 PM SATURDAY...PERSISTENT SOUTHWESTERLY FLOW AROUND THE
BACKSIDE OF A BERMUDA-STYLE HIGH WILL KEEP WINDS IN THE 10 TO 15
KT RANGE FOR MOST OF THE WATERS THROUGH THE NEAR TERM...WITH THE
EXCEPTION OF NEAR THE COAST THIS AFTERNOON AND EVENING. ALONG THE
COAST AN ENHANCED SEA BREEZE CIRCULATION IS KEEPING WINDS ELEVATED
AT 15 TO 20 KTS WITH GUSTS TO 25 KTS. THESE WINDS WILL SUBSIDE
LATER THIS EVENING. SEAS WILL STAY IN THE 2 TO 3 FT RANGE THROUGH
THE NEAR TERM.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 300 PM SATURDAY...SUMMER LIKE SETUP FOR THE SHORT TERM AS
BERMUDA HIGH PRESSURE SPINS OFFSHORE. THIS WILL PUMP SW RETURN FLOW
ACROSS THE WATERS THROUGH THE PERIOD...CREATING WINDS OF 10-15 KTS
THROUGH THE PERIOD...WITH LITTLE FLUCTUATION IN STRENGTH OR
DIRECTION EITHER DAY. THESE WINDS PLUS THE PERSISTENT FETCH AROUND
THE OFFSHORE HIGH PRESSURE WILL CREATE 2-3 FT SEAS EACH DAY...WITH A
WAVE SPECTRUM COMPRISED OF A SOUTHERLY 4-5 SEC WIND WAVE AND A
LOW-AMPLITUDE SE GROUND SWELL.
LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 300 PM SATURDAY...SOUTHEAST FLOW WITH BERMUDA HIGH PRESSURE
WILL PREVAIL ACROSS THE COASTAL WATERS THROUGH THE PERIOD. WIND
SPEEDS OF 10-15 KNOTS CAN BE EXPECTED FOR THE MOST PART WITH
POSSIBLY A FEW HOURS OF HIGHER SPEEDS VIA THE SEA BREEZE. SEAS
WILL REMAIN REPRESENTATIVE OF THE SUMMERTIME PATTERN WITH 2-3
FEET.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...DCH/8
SHORT TERM...JDW
LONG TERM...SHK
AVIATION...BJR/8
AREA FORECAST DISCUSSION
NWS BISMARCK ND
350 AM CDT SUN MAY 11 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 350 AM CDT SUN MAY 11 2014
THE FOCUS IN THE SHORT TERM IS ON THE PROGRESSION OF PRECIPITATION
THROUGH TONIGHT.
LATEST REFLECTIVITY SHOWS THE MAJORITY OF PRECIPITATION OVER NORTH
CENTRAL NORTH DAKOTA. THE 00 UTC WRF AND LATEST HRRR RUNS HAVE
VERIFIED PRETTY WELL WITH CURRENT OBSERVATIONS. ON THE OTHER HAND
THE 00 UTC RUNS OF THE GFS...NAM...ECMWF...AND NHEM GEM HAD A
DIFFICULT TIME NAILING DOWN THE PRECIPITATION OVER THE NORTH CENTRAL
AND ALL OVERPLAYED THE WRAP AROUND PRECIPITATION LOCATED OVER
EASTERN MONTANA AND WESTERN NORTH DAKOTA. WITH THAT SAID USED THE
HRRR AND 00 UTC WRF RUN FOR POPS THROUGH 12 UTC SUNDAY THEN A MODEL
BLEND FROM 12 UTC SUNDAY THROUGH 12 UTC MONDAY SINCE MODEL AGREEMENT
WAS GOOD ON THE WEST TO EAST PROGRESSION OF PRECIPITATION THROUGH SUNDAY.
AT THIS TIME NO THUNDERSTORM ACTIVITY IS EXPECTED SUNDAY...JUST A
CHILLY RAW DAY. WINDS WILL ALSO BE BREEZY 15 TO 25 MPH FROM THE
NORTHWEST SUSTAINED ACROSS THE WEST AND CENTRAL. NO WIND ADVISORY IS
ANTICIPATED AT THIS TIME.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 350 AM CDT SUN MAY 11 2014
THE 00Z GFS/GEM/ECMWF PROG AN OPEN WAVE TO MEANDER OVER
SOUTHEASTERN SASKATCHEWAN/WESTERN NORTH DAKOTA MONDAY. THIS WILL
LEAD TO ENHANCED PRECIPITATION CHANCES EAST OF HIGHWAY 83...MAINLY
OVER THE JAMES RIVER BASIN. THE OPEN WAVE IS THEN PROGGED TO
SLOWLY MEANDER EAST...SHIFTING PRECIPITATION CHANCES EAST ALONG
WITH IT. SOME WRAP AROUND MOISTURE WILL GENERATE A SLIGHT CHANCE
OF SHOWERS OVER WESTERN AND CENTRAL NORTH DAKOTA LATE TUESDAY.
HOWEVER...RAINFALL AMOUNTS SHOULD BE VERY LIGHT IF ANY RAIN WERE
TO DEVELOP.
BY WEDNESDAY AND THURSDAY...SYNOPTIC SUBSIDENCE IS PROGGED TO
OVERSPREAD THE STATE AHEAD OF A DEVELOPING PACIFIC RIDGE. THIS
SHOULD LEAD TO MAINLY DRY CONDITIONS WITH HIGHS IN THE UPPER 50S.
THE MEDIUM RANGE MODELS NOW PROG A WEAK WAVE TO TRAVERSE NORTH
DAKOTA FRIDAY/FRIDAY NIGHT. INDICATED SLIGHT CHANCE POPS AS A
RESULT. THE PACIFIC RIDGE IS THEN FORECAST TO TRANSLATE EAST INTO
THE GREAT PLAINS BY SATURDAY. IF THIS VERIFIES...IT SHOULD GENERATE
DRY CONDITIONS AND HIGHS IN THE MID 60S BY THE END OF THE PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1235 AM CDT SUN MAY 11 2014
SURFACE LOW IS LOCATED JUST SOUTHEAST OF KJMS. WINDS ON THE BACK
SIDE OF THE LOW PRESSURE SYSTEM WILL BE OUT OF THE NORTHWEST AND
INCREASE THROUGH 00 UTC MONDAY FOR ALL TAF SITES IN CENTRAL AND
WESTERN NORTH DAKOTA. SCATTERED SHOWERS AND LOW CEILINGS ACROSS
NORTH DAKOTA WILL CAUSE IFR TO LOW VFR CONDITIONS THROUGH THE 06
UTC TAF CYCLE.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...MM
LONG TERM...TM
AVIATION...MM
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1235 AM CDT SUN MAY 11 2014
.UPDATE...
ISSUED AT 1235 AM CDT SUN MAY 11 2014
UPDATED POPS TO MATCH LATEST RADAR REFLECTIVITY. THE 00 UTC WRF
AND LATEST HRRR CONTINUE TO SHOW THE MAJORITY OF PRECIPITATION
OVER NORTH CENTRAL NORTH DAKOTA...WITH SOME LIGHT PRECIPITATION
ALONG THE DAKOTA MONTANA BORDER. TOOK OUT THE MENTION OF THUNDER
AS THUNDERSTORM ACTIVITY SEEMS TO HAVE COME TO AN END.
UPDATE ISSUED AT 933 PM CDT SAT MAY 10 2014
LARGE PRECIPITATION REGION ON RADAR ALONG AND NORTH OF OCCLUDED
FRONTAL BOUNDARY ACROSS SOUTHEAST NORTH DAKOTA. UPLIFT OVER THE
FRONT AIDING IN GENERATING SCATTERED THUNDERSTORMS ACROSS THE
JAMES RIVER VALLEY. RAISED POPS ACROSS THE EAST THROUGH NORTH
CENTRAL. THIS AREA WILL PIVOT NORTH AND WEST THEN DIMINISH SUNDAY.
UPDATE ISSUED AT 657 PM CDT SAT MAY 10 2014
AS OF 630 PM CDT THUNDERSTORMS HAVE ENDED OVER THE NORTHWEST. NOW
THE FOCUS WILL BE ON THE WEAK LINE OF THUNDERSTORMS MOVING UP THE
JAMES RIVER VALLEY. THESE STORMS HAVE FORMED NORTH OF THE
OCCLUDED FRONT IN SOUTHEAST NORTH DAKOTA. EXPECT THESE TO BE
ACTIVE FOR A FEW HOURS BUT ALREADY SHOWING SIGNS OF DIMINISHING AS
THEY MOVE AWAY FROM THE BETTER CAPE/MID LEVEL LAPSE RATES ACROSS
THE FAR SOUTHEAST.
UPDATE ISSUED AT 350 PM CDT SAT MAY 10 2014
ADDED THIS UPDATE FOR SCATTERED TO ISOLATED THUNDERSTORMS
NORTHWEST REMAINDER OF THIS AFTERNOON.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 233 PM CDT SAT MAY 10 2014
THE MAIN FORECAST ISSUES IN THE SHORT TERM PERIOD ARE PRECIPITATION
TRENDS AND AMOUNTS TONIGHT THROUGH SUNDAY.
IN THE NEAR TERM...SHOWERS ARE MOST WIDESPREAD ACROSS THE JAMES
RIVER VALLEY...THEN STRETCHING WEST ALONG THE I-94 CORRIDOR INTO
THE SOUTHWEST COUNTIES. THE MODEL CONSENSUS...INCLUDING THE HIGH
RESOLUTION HRRR AND WRF...INDICATE THE FOCUS OF THE HEAVIER RAIN
WILL SHIFT INTO THE NORTHWEST AND NORTH CENTRAL COUNTIES LATER
TONIGHT INTO SUNDAY MORNING. LINGERING SHOWERS ARE POSSIBLE ACROSS
THE EAST SUNDAY AFTERNOON. ELEVATED INSTABILITY FAVORS ISOLATED LATE
AFTERNOON/EVENING THUNDERSTORMS MAINLY EAST OF BISMARCK INTO THE
JAMES RIVER VALLEY...BUT NO SEVERE WEATHER IS EXPECTED. FOR
SUNDAY...EXPECT A CHILLY AND RAW DAY...WITH HIGHS IN THE UPPER 40S
TO UPPER 50S...ABOUT 10-15 DEGREES BELOW NORMAL. A NORTHWEST WIND
WILL BE SUSTAINED AT 20 TO 25 MPH AND MAY FLIRT WITH ADVISORY
CRITERIA ACROSS THE FAR SOUTHWEST.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 233 PM CDT SAT MAY 10 2014
AN SEMI-ACTIVE AND COOL WEATHER PATTERN WILL BE THE MAIN STORY
THROUGH THE LONG TERM FORECAST PERIOD.
UPPER LEVEL TROUGH OVER THE ROCKIES WILL MOVE SLOWLY EAST INTO
THE CENTRAL CONUS SUNDAY NIGHT INTO MONDAY...THEN OFF TO OUR EAST
TUESDAY FOLLOWED BY A QUASI-ACTIVE NORTHWEST FLOW PATTERN FOR THE
REST OF THE WORK WEEK.
FOR SUNDAY NIGHT-MONDAY...SUBSIDENCE ACROSS THE WESTERN HALF OF
THE STATE WILL DRY THINGS OUT WITH LINGERING MOISTURE EAST ALONG
THE UPPER TROUGH. WITH THE TROUGH SLOW TO MOVE EAST...DIURNALLY
DRIVEN SHOWERS WILL BE POSSIBLE BOTH MONDAY AND TUESDAY. MAY BE
COLD ENOUGH DURING THE OVERNIGHT/MORNING PERIODS FOR A RAIN/SNOW
MIX SOME LOCATIONS.
NORTHWEST FLOW WED-FRI WITH POSSIBLE EMBEDDED WAVES AND THE UPPER
JET ALOFT CONTINUING THE THREAT FOR PERIODS OF LIGHT PRECIPITATION.
TEMPERATURES COOL (HIGHS 40S/50S AND LOWS 30S) THROUGH MID
WEEK...WITH A MODERATION IN TEMPERATURES TOWARDS NEXT WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1235 AM CDT SUN MAY 11 2014
SURFACE LOW IS LOCATED JUST SOUTHEAST OF KJMS. WINDS ON THE BACK
SIDE OF THE LOW PRESSURE SYSTEM WILL BE OUT OF THE NORTHWEST AND
INCREASE THROUGH 00 UTC MONDAY FOR ALL TAF SITES IN CENTRAL AND
WESTERN NORTH DAKOTA. SCATTERED SHOWERS AND LOW CEILINGS ACROSS
NORTH DAKOTA WILL CAUSE MVFR TO LOW VFR CONDITIONS THROUGH THE 06
UTC TAF CYCLE.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...MM
LONG TERM...NH
AVIATION...MM
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
404 AM CDT SUN MAY 11 2014
.DISCUSSION...
AT 3 AM...TEMPERATURES WERE STILL IN THE MID 70S. SOME PATCHY
DRIZZLE MOVED THROUGH EARLIER IN THE NIGHT AND WOULD NOT BE
SURPRISED IF MORE LIGHT RAIN DEVELOPS THIS MORNING. THE RAP 13
SHOWS A CLUSTER OF SHRA/TSRA DEVELOPING OVER PARTS OF EASTERN
HARRIS...GALVESTON...LIBERTY AND CHAMBERS COUNTIES THIS AFTN. THE
HRR IS LESS AGGRESSIVE BUT IT SHOWS SOMETHING SIMILAR. PW VALUES
ARE PROGGED TO BE AROUND 1.4-1.5 INCHES AND UPPER LEVEL WINDS WILL
REMAIN BROADLY DIVERGENT. CAN`T RULE OUT A STRAY SHOWER ACROSS THE
CWA...SO WILL MAINTAIN THE 20 POPS ALREADY IN PLACE.
PWATS INCREASE TO AROUND 1.7 INCHES ON MONDAY AFTN. CAPE VALUES
ARE ABOVE 2000 AND LI`S ARE -8. A CAPPING INVERSION IS STILL IN
PLACE DURING THE MORNING BUT RAPIDLY ERODES IN THE AFTN. A WEAK
UPPER LEVEL DISTURBANCE WILL APPROACH SE TX IN THE AFTN AND THIS
FEATURE COUPLED WITH STRONGLY DIVERGENT UPPER LEVEL WINDS AND
DAYTIME HEATING SHOULD ALLOW SHRA/TSRA TO DEVELOP IN THE AFTN.
ALTHO CURRENTLY NOT OUTLOOKED BY SPC...THERE ARE ENOUGH PARAMETERS
IN PLACE TO GET AT LEAST SOME PULSE SEVERE STORMS ON MON AFTN.
THE UPPER TROUGH INCHES EVER CLOSER MON NITE AND TUESDAY. THE
UPPER JET IS IN A FAVORABLE POSITION AND SE TX WILL LIE IN A RRQ
OF A SPLITTING JET. PWATS INCREASE TO 1.7-1.9 INCHES AND CAPPING
IS NO LONGER AN ISSUE. A SURFACE COLD FRONT WILL SLOWLY CROSS SE
TX ON TUESDAY AND WILL SERVE AS THE LOW LEVEL FOCUS FOR SHRA/TSRA.
POST FRONTAL RAINS ARE ALSO EXPECTED AS THE UPPER TROUGH LAGS
BEHIND A BIT. CONVERGENCE IS ALSO LOOKING PRETTY STOUT AT 850 MB.
LOCALLY HEAVY RAIN WILL BE POSSIBLE ON TUESDAY OVER PARTS OF SE
TX DUE TO THE HIGH MOISTURE CONTENT...FAVORABLE UPPER LEVEL WINDS
AND THE POTENTIAL FOR TRAINING OF STORMS. WPC HAS A RATHER
GENEROUS QPF BULLSEYE OVER SE TX. LIGHT RAIN WILL LINGER TUESDAY
NIGHT AND WILL END WEDNESDAY MORNING ONCE THE UPPER TROUGH PUSHES
EAST OF THE REGION. FWIW...THE NAM 12 IS CONSIDERABLY WEAKER WITH
THE UPPER TROUGH AND DRIER WITH VERY LITTLE RAIN OVER SE TX. THE
NAM IS CURRENTLY THE OUTLIER BUT IT HAS PERFORMED RELATIVELY WELL
AS OF LATE.
SKIES SHOULD CLEAR ON WEDNESDAY AFTN WITH GENERALLY CLEAR SKIES
THROUGH NEXT WEEKEND. TEMPERATURES WILL BE UNSEASONABLY COOL IN
THE WAKE OF TUESDAYS COLD FRONT. MIN TEMPS WILL FALL INTO THE 50S
WED-FRI WITH MAYBE SOME 40S ON THURSDAY MORNING. TEMPS WILL WARM
TO SEASONAL NORMALS BY NEXT WEEKEND. 43
&&
.MARINE...
IN ADDITION TO MODERATE TO STRONG ONSHORE WINDS...AREAS OF DRIZZLE
AND LIGHT RAIN WILL AFFECT THE MARINE AREAS THIS MORNING. WENT WITH
HIGHER WIND SPEEDS THAN FORECAST BY THE MODELS GIVEN THE GOOD
THERMAL GRADIENT IN PLACE. THE PRESSURE GRADIENT IS ALSO FORECAST BY
THE MODELS TO BE INCREASING LATER THIS MORNING.
LIKED A COMBINATION OF THE NAM12 AND MOS GUIDANCE TONIGHT THROUGH
MONDAY NIGHT. STAYED WITH THE GFS OUTPUT FOR THE FRONTAL PASSAGE OFF
THE COAST TUESDAY EVENING. STRONG OFFSHORE WINDS WILL THEN QUICKLY
BECOME NORTHEAST AND DIMINISH LATE WEDNESDAY AND THURSDAY MORNING.
40
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 89 73 87 65 74 / 20 10 50 60 60
HOUSTON (IAH) 88 74 86 72 82 / 20 10 40 50 60
GALVESTON (GLS) 83 74 82 74 81 / 20 10 30 40 60
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 1 PM CDT THIS
AFTERNOON FOR THE FOLLOWING ZONES: GALVESTON BAY...
MATAGORDA BAY...WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL 20 NM TO 60 NM...WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND
TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH ISLAND TO
FREEPORT OUT 20 NM.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
245 AM CDT SUN MAY 11 2014
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 245 AM CDT SUN MAY 11 2014
AXIS OF THE WEST COAST LONG WAVE TROUGH WILL SLIDE OVER THE PLAIN
STATES ON MON...SLOWLY EASING ACROSS THE UPPER MISSISSIPPI RIVER
VALLEY ON WED. BITS OF UPPER LEVEL ENERGY WILL SPIN OUT OF THE
TROUGH...WITH THESE SHORTWAVES TAKING AIM ON THE REGION TODAY AND
MONDAY.
AT THE SFC...A WARM FRONT CURRENTLY WAS RUNNING FROM KS EASTWARD
THROUGH THE MID MISSISSIPPI RIVER VALLEY. THIS IS SLATED TO LIFT
NORTHWARD THROUGH THE DAY TODAY AS A SFC LOW TRACKS INTO IA BY 06Z
TONIGHT. STRONG LOW LEVEL MOISTURE TRANSPORT POINTS INTO AND ACROSS
THE WARM FRONT...DRIVEN BY A 40-50 KT 850 MB JET...AND NOSES INTO
NORTHEAST IA/SOUTHWEST WI BY 06Z. THIS RIBBON OF MOISTURE HOLDS
AHEAD OF A COLD FRONT THROUGH MONDAY...ALTHOUGH NOT NEARLY AS STRONG
AS WHAT IS EXPECTED FOR TONIGHT.
INSTABILITY CLIMBS THROUGH THE DAY...WITH 1000-2000 J/KG OF MUCAPE
STILL EXPECTED FOR MUCH OF THE LOCAL FORECAST AREA BY TONIGHT. IT
STAYS FAIRLY UNSTABLE THROUGH MONDAY...STILL AHEAD OF THE COLD FRONT
WITH THE WARM FRONT EXPECTED TO BE NORTH...SBCAPES AROUND 1500 J/KG.
A LOOK AT THE BUFKIT SOUNDINGS SHOWS THAT MUCH OF THAT CAPE IS OF
THE SKINNY VARIETY TONIGHT...MEANING THAT VIGOROUS UPDRAFTS/RAPID
DEVELOPMENT ARE NOT SUPPORTED BY THE INSTABILITY.
0-6 KM SHEAR RAMPS UP TO 40-50 KTS BY THIS EVENING...BUT A LOT OF
THAT IN THE 0-3 KM LAYER...AROUND 40 KTS OR SO. GOOD TURNING IN THE
LOWEST 1 KM PER BUFKIT HODO...AND 0-1 KM SHEAR RANGES FROM 20-30
KTS DURING THE NIGHT.
SEVERE THREAT HAS CONTINUED TO INCREASE OVER THE PAST COUPLE
DAYS...AND 00Z MODELS ARE NO DIFFERENT. THE STRONG LOW LEVEL
JET/MOISTURE TRANSPORT WILL BE A SIGNIFICANT FACTOR...ALONG WITH THE
POSITIONING OF THE WARM FRONT. WHILE THE INSTABILITY IS NOT OVERLY
FAVORABLE...ADD IN THE VERY GOOD SHEAR AND STORM DEVELOPMENT IS
SUPPORTED. LARGE HAIL AND DAMAGING WINDS ARE THREATS...WINDS
ESPECIALLY IF THERE IS NO NEAR SFC STABLE LAYER. THE LOW LEVEL
CURVATURE/SHEAR ALSO BRINGS A TORNADO THREAT...ESPECIALLY AROUND THE
WARM FRONT WHICH WILL SERVE TO PROVIDE ADDITIONAL...LOCALIZED
VORTICITY. NAM12 SIG TOR PARAMETER AS HIGH AS 2-4 THIS EVENING FOR
NORTHEAST IA/SOUTHWEST WI.
ITS NOT CLEAR-CUT ON HOW HIGH THE RISK FOR SEVERE WILL BE...OR WHERE
IT WILL BE THE GREATEST. POSITIONING OF THE WARM FRONT WILL BE
SIGNIFICANT. GFS/NAM TRENDING TOWARD BRINGING THAT FRONT INTO
CENTRAL IA INTO NORTHERN ILL...ADVANCING NORTH DURING THE
EVENING...NEAR THE I-90 CORRIDOR/SOUTH AROUND 06Z. ITS NOT CERTAIN
IT WILL RUN THIS FAST NORTH AS CONVECTION ALONG AND NORTH OF THE
BOUNDARY SHOULD SERVE TO TEMPER ITS MOVEMENT.
IN ADDITION...THERE WILL BE A THREAT FOR SOME SHOWERS/STORMS THIS
AFTERNOON...WELL BEFORE THE EXPECTED CONVECTION OF TONIGHT. THE LOW
LEVEL JET IS EXPECTED TO SPARK A THUNDERSTORM COMPLEX OVER THE
SOUTHERN PLAINS...WHICH THE HRRR TAKES NORTHEAST TOWARD THE AREA.
HOW LONG THE CONVECTION WILL HOLD TOGETHER AS THE LOW LEVEL
JET/MOISTURE TRANSPORT TEMPORARILY WEAKENS AT MIDDAY IS IN QUESTION.
ITS MCV COULD SERVE AS FORCING MECHANISM LATER IN THE AFTERNOON. IF
THE PCPN DOESN/T REACH THE FORECAST AREA...DEBRIS CLOUDS PROBABLY
WILL...AND COULD TEMPER THE WARMING AND THUS INSTABILITY SOME NORTH
OF THE WARM FRONT.
ALL THIS SAID...SEE A SEVERE THREAT TONIGHT...ESPECIALLY ACROSS
NORTHEAST IA/SOUTHWEST WI. PROBABLY MORE MID/LATE EVENING. HAIL IS
THE TOP THREAT...BUT SIGNIFICANT 0-3 KM SHEAR COULD RESULT IN
DAMAGING WINDS IF THERE IS NOT A STRONG STABLE NEAR SFC LAYER.
BUFKIT SOUNDINGS SUGGEST THERE PROBABLY WON/T BE. AND...A TORNADO
THREAT CANNOT BE RULED OUT. LOW LEVEL CURVATURE AND 0-1 KM SHEAR
SUPPORTS IT...AND THE SIG TOR PARAMETER PEGS IT. ESPECIALLY
CONCERNED ABOUT ANY STORMS RIDING THE WARM FRONT. THERE ARE CAVEATS
TO THE RISK PER WHERE CONVECTION GOES...BOUNDARIES...ETC...BUT ITS A
SITUATION THAT NEEDS TO BE MONITORED VERY CLOSELY. EXPECTING WATCHES
AND WARNINGS TONIGHT.
ALL THAT SAID AND HAVEN/T EVEN TOUCHED ON THE HEAVY RAIN THREAT.
MORE ON THAT IN THE HYDROLOGY SECTION BELOW.
.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 245 AM CDT SUN MAY 11 2014
GFS/ECMWF PROMISE TO KEEP THE REGION UNDER THE INFLUENCE OF AN UPPER
LEVEL TROUGH FOR MUCH OF THE NEW WEEK. BITS OF ENERGY WILL MOVE
THROUGH THE TROUGH AND BRING A SHOWER THREAT FROM TIME TO
TIME...ALTHOUGH WHEN/WHERE THE RAIN CHANCES WILL BE ARE NOT
CERTAIN...WITH MODEL VARIANCES KEEPING CONFIDENCE LOW. WILL STAY
WITH CONSENSUS SOLUTION FOR CHANCES. TEMPERATURES ARE GOING TO TAKE A
TUMBLE DOWNWARD...WITH EC 850 MB TEMP ANOMALIES HOVERING AROUND -1.
HIGHS WILL STRUGGLE TO BREAK 60 DEGREES SOME DAYS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT
1149 PM CDT SAT MAY 10 2014
SOME SCATTERED RAIN SHOWERS HAVE DEVELOPED ACROSS SOUTHEAST
MINNESOTA AND WESTERN WISCONSIN AND WILL TRACK QUICKLY TO THE EAST
OVERNIGHT. CONDITIONS ARE MAINLY VFR THOUGH A FEW SPOTS HAVE BRIEFLY
DROPPED TO MVFR WITH VISIBILITY GOING DOWN TO 5SM. BASED ON THE LOW
CHANCES THAT ONE OF THESE SHOWERS WOULD DIRECTLY HIT RST/LSE...HAVE
JUST LEFT IT AS VCSH AND VFR.
THE MAIN FOCUS THEN GOES TO TOMORROW EVENING WHEN IT APPEARS LIKELY
THAT WIDESPREAD THUNDERSTORMS WILL DEVELOP ACROSS THE REGION AS A
WARM FRONT LIFTS NORTH INTO THE REGION. THERE IS SOME QUESTION ABOUT
THE EXACT START UP TIME OF THE CONVECTION...BUT IT APPEARS MOST
LIKELY TO OCCUR AROUND 2Z AT RST AND 4Z AT LSE. VISIBILITY SHOULD
DROP TO IFR OR LOWER IF THE STORMS TRAIN OVER THE SAME LOCATIONS
TOMORROW EVENING. BASED ON THE HIGH CONFIDENCE THAT WE WILL HAVE
RAINS/STORMS...HAVE PUT A PREVAILING TSRA GROUP IN THE TAFS FOR
TOMORROW EVENING.
&&
.HYDROLOGY...
ISSUED AT 245 AM CDT SUN MAY 11 2014
SIGNIFICANT LOW LEVEL MOISTURE TRANSPORT KICKS IN TONIGHT...AND
WHILE WEAKENING ON MONDAY...WILL CONTINUE TO FUEL SHOWERS AND
THUNDERSTORMS THROUGH MON NIGHT. PW/S CLIMB TO AROUND 1.5 INCHES.
EXPECT SOME STORMS OVER THE NEXT COUPLE DAYS TO PRODUCE HEAVY RAIN.
MODELS DROP 1-2 INCHES LATE TONIGHT INTO TUE FOR MUCH OF THE
FORECAST AREA. LOCALLY HIGHER AMOUNTS POSSIBLE. THE HEAVIEST RAIN
WILL FALL TONIGHT. DON/T EXPECT A WIDESPREAD FLOOD THREAT AT THE
MOMENT...BUT THERE COULD BE SOME LOCALIZED IMPACTS.
MEANWHILE...MINOR FLOODING/HIGH WATER CONTINUES ALONG PORTIONS OF
THE MISSISSIPPI RIVER. THE ADDITIONAL RAINS COULD HAVE IMPACTS ON
BOTH TRIBUTARIES AND THE MISSISSIPPI RIVER...SLOWING THE RATES OF
FALL...AND/OR PRODUCE ADDITIONAL RISES OR RENEWED FLOODING.
CHECK THE LATEST HYDROLOGIC STATEMENTS FOR THE DETAILS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...RIECK
LONG TERM....RIECK
AVIATION.....HALBACH
HYDROLOGY....RIECK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1149 PM CDT SAT MAY 10 2014
.UPDATE...
ISSUED AT 834 PM CDT SAT MAY 10 2014
MAIN BAND OF RAIN IS ENTERING EASTERN MINNESOTA AND IOWA ALONG THE
LEAD MID LEVEL SHORT WAVE TROUGH THAT RUNS FROM SOUTHEAST NORTH
DAKOTA THROUGH SOUTHWEST MINNESOTA. THE 11.00Z RAP CONTINUES TO
SHOW A WEAKENING TREND IN INSTABILITY...BUT STILL HAS SOME FEEDING
INTO THE BACK EDGE OF THE SHORT WAVE TO WARRANT KEEPING A MENTION
OF THUNDER IN THROUGH THIS EVENING. HAVE SPED UP THE END TIME OF
THIS RAIN BASED ON CURRENT EXTRAPOLATION AND THE PAST FEW RUNS OF
THE HRRR WHICH HAS HAD A GOOD HANDLE ON THIS CONVECTION. WHILE
0-6KM WIND SHEAR IS DECENT...IT IS ALL IN THE LOW LEVELS AND NOT
IN THE LAYER WHERE THIS VERY SKINNY/WEAK INSTABILITY IS IN THE MID
LEVELS. THUS...AM NOT EXPECTING ANYTHING SEVERE THIS EVENING.
HAVE NOT MADE ANY CHANGES TO THE FORECAST FOR TOMORROW...BUT AS
PREVIOUSLY MENTIONED...IT WILL ALL DEPEND ON HOW FAR NORTH THE
WARM FRONT MAKES IT. ONE THING APPEARS CERTAIN AND THAT IS THE
INCREASE IN LOW LEVEL MOISTURE TRANSPORT THROUGH THE DAY AND INTO
THE NIGHT WHICH MAY LEAD TO SOME FLOODING ISSUES IF STORMS TRAIN
TO THE NORTH OF THE FRONT. WILL HAVE TO SEE HOW THE 11.00Z MODELS
COME UP BEFORE MAKING ANY WHOLESALE CHANGES TO THE FORECAST.
&&
.SHORT TERM...(TONIGHT THROUGH SUNDAY NIGHT)
ISSUED AT 310 PM CDT SAT MAY 10 2014
MAIN FORECAST CONCERNS THIS PERIOD...SHRA/TSRA CHANCES THIS EVENING
AND AGAIN SUN AFTERNOON/NIGHT. POTENTIAL HEAVY RAINS SUN NIGHT.
18Z DATA ANALYSIS HAD A WEAK RIDGE OF HIGH PRESSURE FROM NORTHEAST
MN THRU SOUTHEAST WI. SUNNY...QUIET DAY OVER THE NORTHEAST HALF OF
THE REGION. WV IMAGERY SHOWED A MORE ROBUST LOOKING SHORTWAVE
LIFTING NORTHEAST ACROSS SD/NEB EARLY THIS AFTERNOON. THIS WAVE AND
SOME 850-700MB MOISTURE TRANSPORT/THERMO-DYNAMIC FORCING RESPONSIBLE
FOR A BROAD BAND OF SCT SHRA/ISOLATED TSRA LIFTING ACROSS NORTHERN
IA/SOUTHWEST MN. PER 10.12Z KMPX SOUNDING...PLENTY OF DRY AIR ABOVE
850MB AHEAD OF THIS BAND OF SHRA/TSRA TO OVERCOME BEFORE PRECIP
REACHES THE GROUND...AND MOST RAIN AMOUNTS SO FAR TODAY HAVE BEEN A
TRACE TO A FEW HUNDREDTHS OF AN INCH.
10.12Z MODELS INITIALIZED WELL...BUT FOR GFS ABOUT 5F HIGH ON SFC
DEW POINTS ACROSS THE SOUTH HALF OF THE UPPER MS VALLEY.
SOLUTIONS CONTINUE TO OFFER A TIGHTER CONSENSUS ON THE SHORTWAVE
TO LIFT ACROSS THE UPPER MIDWEST TONIGHT AND THE NEXT STRONG
TROUGHING/ ENERGY TO CROSS THE ROCKIES SUN/SUN NIGHT.
SLOWER/STRONGER ECMWF/ CAN-GEM OFFERING THE BETTER RUN-TO-RUN
CONSISTENCY WITH THE ROCKIES TROUGHING LATE SUN/SUN NIGHT WITH
GFS/NAM SLOWING TO MATCH UP. NAM APPEARS AS BIT OF AN OUTLIER AT
12Z MON WITH A FURTHER NORTH/EAST SFC LOW/TRAILING COLD FRONT AND
ITS SOLUTION GENERALLY DISCOUNTED. GIVEN THE NOW RATHER TIGHT NON-
NAM CONSENSUS THRU 12Z MON...SHORT- TERM FCST CONFIDENCE FOR A
RATHER ACTIVE PERIOD IS GOOD THIS CYCLE.
FIRST SHORTWAVE CROSSING THE UPPER MIDWEST TONIGHT WEAKENS AS
LOOSES THE BATTLE WITH THE RISING HGTS/RIDGING AHEAD OF THE
STRONGER TROUGHING DIGGING INTO THE ROCKIES. 925-700MB MOISTURE
TRANSPORT/ WARM ADVECTION AND SOME 295-305K ISENTROPIC LIFT STILL
SPREADS NORTHEAST ACROSS THE FCST AREA MAINLY LATE THIS
AFTERNOON/EVENING... WITH STEEPER MID LEVEL LAPSE RATES AND WEAK
INSTABILITY. WILL CONTINUE SHRA/TSRA CHANCES THRU THE EVENING...IN
THE 20-50 PERCENT RANGE...THEN TAPER/END THEM AFTER MIDNIGHT AS
THE LOWER LEVEL FORCING WEAKENS/MOVES EAST OF THE FCST AREA. MOST
RAIN AMOUNTS TONIGHT TO BE QUITE LIGHT.
BREAK FROM THE RAIN CHANCES LATE TONIGHT/SUN MORNING AS SOME 850-
700MB DRYING TEMPORARILY SPREADS ACROSS THE AREA. MOISTURE RETURN
AHEAD OF THE CENTRAL PLAINS LEE LOW ALREADY SPREAD ACROSS THE AREA
SUN MORNING...WITH THE 700MB MOISTURE ARRIVING DURING THE LATER
MORNING/EARLY AFTERNOON HOURS AND 925-50MB MOISTURE ARRIVING DURING
THE AFTERNOON. PW VALUES OF AROUND 1.5 INCHES TO SPREAD NORTH ACROSS
THE AREA FOR SUN AFTERNOON/NIGHT. QUESTION NO LONGER SEEMS IF ITS
GOING TO RAIN LATE SUN AFTERNOON/NIGHT BUT HOW MUCH. BROAD/DEEP
LAYERED FORCING/LIFT AHEAD OF THE SFC THRU MID LEVEL TROUGH SPREADS
ACROSS WITH THE MOISTURE INCREASE SUN AFTERNOON/NIGHT.
AT 00Z MON...MODEL SOUNDINGS SHOWING STABILITY/CIN OF 50-150IN THE
SFC-700MB LAYER WITH MUCAPES OF 500-1500 J/KG OVER MAINLY THE SOUTH
1/3 OF THE FCST AREA. LFC AROUND 700MB IN THE SOUNDINGS WITH THE CIN
IN A RATHER DEEP 900-700MB LAYER. CAPE PROFILE IS DEEP...BUT SKINNY.
WITH WARM CLOUD DEPTH OF AROUND 3500 METERS...THE SKINNY CAPE OF 500-
1500 J/KG DOES NOT SEEM LIKE ENOUGH FOR A BIG HAIL THREAT. WITH THE
AREA LOOKING TO BE NORTH OF THE WARM FRONT SUN EVENING AND THE CIN
BELOW 700MB...APPEARS MAIN TORNADO AND STRONG WIND THREAT WOULD
BE SOUTH OF THE FCST AREA. ALSO...NUMEROUS SHRA/TSRA EXPECTED TO
BE SPREADING INTO/ACROSS THE AREA SUN AFTERNOON/ EVENING...ALL
COMPETING FOR THE SAME CAPE/SHEAR...WILL REDUCE THE SEVERE THREAT
FROM ANY ONE TSRA. CONCERNS AS WELL ON SUN WITH HIGH TEMPS BEING
TOO WARM AND CAPE ON THE HIGH SIDE GIVEN THICKENING
CLOUDS/SHRA/TSRA SPREADING NORTH INTO THE AREA DURING THE
AFTERNOON.
THE 3500 METER WARM CLOUD DEPTH...A WARM FRONT TO THE SOUTH FOR
LIFTING...PW VALUES NEAR 200 PERCENT OF NORMAL AND A FEED OF THIS
MOISTURE ON A 40-50KT 850MB JET SUN NIGHT ALL POINT TSRA BEING
EFFICIENT RAIN MAKERS AND A HEAVY RAIN THREAT. CONSIDERED A FLOOD
WATCH FOR SUN NIGHT/MON...BUT IT WOULD HAVE AND TO BE RATHER BROAD
WITH QPF DETAIL DIFFERENCES AMONG THE MODELS. WILL ISSUE AND ESF FOR
NOW AND PASS ALONG CONCERNS TO THE MIDNIGHT CREW.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 310 PM CDT SAT MAY 10 2014
MAIN FORECAST CONCERNS MON THRU TUE NIGHT...SHRA/TSRA CHANCES/RAIN
AMOUNTS MON INTO MON NIGHT...COOLING TEMPERATURES.
MODEL RUNS OF 10.12Z OFFERING A TIGHTER CONSENSUS MON/MON NIGHT AS
THE MID LEVEL TROUGH LIFTS INTO THE UPPER MIDWEST AND THE SFC LOW
LIFTS TO LK SUPERIOR. TREND IS TOWARD COMPROMISE OF THE EARLIER RUNS
ON STRENGTH/TIMING OF THE MID LEVEL TROUGH INTO THE REGION WITH
SOMEWHAT BETTER RUN-TO-RUN CONSISTENCY BY THE ECMWF. IMPROVING
CONSENSUS TUE/TUE NIGHT AS THE TROUGH VIRTUALLY STALLS OVER THE
CENTRAL CONUS. FCST CONFIDENCE IN THE MON-TUE NIGHT PERIOD IS
AVERAGE TO GOOD THIS CYCLE.
BROAD/DEEP FORCING/LIFT CONTINUES OVER THE AREA MON...ALONG WITH A
FEED OF THE 1.5 INCH PW VALUES ON A 30-40KT 850MB JET. STRONGEST OF
THIS IS OVER THE FCST AREA IN THE MORNING...GRADUALLY TRANSLATING
EAST MON AFTERNOON/EVENING AS THE SFC THRU 850MB COLD FRONT/TROUGH
MOVE EAST INTO/ACROSS THE AREA. PLENTY OF FORCING/LIFT REMAINS OVER
THE WEST SIDE OF THE FCST AREA MON AFTERNOON/EVENING...WITH THE 700-
500MB TROUGH AXIS STILL WEST OF THE AREA AND SHORTWAVES LIFT UP THE
EAST SIDE OF THE TROUGH THRU WESTERN MN. HEAVIEST RAIN THREAT SHIFTS
EAST OF THE AREA THRU MON AFTERNOON/EVENING...BUT SHRA/TSRA LOOK TO
CONTINUE ACROSS THE ENTIRE FCST AREA MON AFTERNOON. AFTER A POSSIBLE
1 TO 2 INCHES OF RAIN SUN NIGHT...ANOTHER 1/4 TO 3/4 INCH OF RAIN
POSSIBLE MONDAY. SHRA/TSRA THEN TAPER OFF AND EXIT EAST THRU MON
NIGHT/TUE MORNING AS THE SFC-850MB TROUGH/FRONT MOVE EAST OF THE
AREA.
CONCERNS WITH THE SEVERE THREAT DEPICTED IN DAY 3 SIMILAR TO THOSE
CENTERED ON SUN EVENING. SHRA/TSRA SHOULD BE ONGOING ACROSS MUCH OF
THE UPPER MIDWEST MON MORNING...AND CONTINUE MUCH OF THE DAY. DEBRIS
CLOUDS AND THE RAIN SHOULD LIMIT HIGH TEMPS AND POTENTIAL FOR CAPE
TO BUILD ACROSS THE AREA. USED THE MODEL/ENSEMBLE CONSENSUS HIGHS
FOR MON BUT IF CLOUDS/SHRA/TSRA PREVAIL...THESE ARE LIKELY TOO WARM
RESULTING IN TOO MUCH CAPE IN THE PROGS. MON CAPE PROFILES ALSO DEEP
AND SKINNY SIMILAR TO SUN EVENING. NUMEROUS SHRA/TSRA ALL COMPETING
FOR THE SAME CAPE/SHEAR WILL AGAIN LIMIT THE SEVERE POTENTIAL WITH
ANY ONE STORM.
DRIER/COOLER 925-700MB AIR WRAPS ACROSS THE AREA FOR TUE AFTERNOON/
NIGHT FOR WHAT SHOULD BE DRY PERIODS AND A DECREASE OF CLOUDS. 850MB
TEMPS IN THE +2C TO -1C RANGE BY 12Z WED. THIS PLUS LIGHT WINDS AND
MOSTLY CLEAR SKIES TUE NIGHT...LOWS IN THE UPPER 30S-LOW 40S WED
MORNING APPEAR REASONABLE.
FOR WEDNESDAY THRU SATURDAY.../DAYS 4 TO 7/...
MAIN FORECAST CONCERNS THIS PERIOD...COOL TEMPERATURES AND -SHRA
CHANCES THRU THE PERIOD.
MEDIUM RANGE MODEL RUNS OF 10.00Z/10.12Z HAVE COME INTO BETTER
AGREEMENT WED/THU ON LOCATION/STRENGTH OF THE TROUGHING TO SLOWLY
MOVE ACROSS CENTRAL NOAM. MODELS CONVERGING TOWARD THE EARLIER
ECMWF RUNS. IMPROVING CONSENSUS FOR SOME NORTHERN STREAM ENERGY TO
DROP INTO THE UPPER MIDWEST THU/FRI...FURTHER DEEPENING THE TROUGH
AND CARVING OUT A MID LEVEL OVER THE WESTERN GREAT LAKES FOR FRI
INTO SAT. GIVEN THE IMPROVED MEDIUM RANGE MODEL CONSENSUS...DAY
4-7 FCST CONFIDENCE IS GENERALLY GOOD THIS CYCLE...ESPECIALLY FOR
BELOW NORMAL TEMPERATURES.
ONE SURGE OF COLDER LOW LEVEL HAS ALREADY SETTLED OVER THE REGION BY
WED. A SECONDARY...EVEN COLDER SURGE IS POISED TO DROP SOUTH INTO
THE REGION FOR THU/FRI. 850MB TEMPS PROGGED TO BOTTOM OUT IN THE
-1C TO -3C RANGE AT 12Z FRI. SOME TEMP RECOVERY SAT AS WARMER AIR
ACTUALLY WRAPS IN FROM THE NORTH. SIGNAL REMAINS CONSISTENT FOR
850MB TEMPS TO BE SOME 1.5 TO 2 STANDARD DEVIATIONS BELOW NORMAL
ACROSS THE UPPER MIDWEST FOR MOST OF THE WE-SAT PERIOD. CONFIDENCE
IS GOOD FOR DAY 4-7 HIGHS TO BE SOME 10-15F BELOW NORMAL. LOWS
THRU THE PERIOD A LITTLE TRICKER AND DEPENDENT ON EXTENT OF CLOUD
COVER ANY ONE NIGHT. WITH MODEST 925-700MB MOISTURE AND THE DEEP
COLD CORE TROUGH/LOW AND CYCLONIC FLOW OVER THE REGION...CLOUDS
EXPECTED TO PREVAIL MUCH OF THE WED-SAT PERIOD. IF ANY ONE OF THE
NIGHTS ENDS UP MORE CLEAR THAN CLOUDY...PATCHY FROST WOULD BE
EXPECTED...ESPECIALLY ALONG/NORTHEAST OF I-94 THU/FRI NIGHTS. FOR
NOW THE MODEL/ENSEMBLE CONSENSUS HIGHS/LOWS FOR WED- SAT ARE WELL
TRENDED.
LESS CONFIDENCE ON -SHRA CHANCES IN THE WED-SAT PERIOD AS THESE
CHANCES WILL DEPEND ON THE TIMING OF STRONGER SHORTWAVES THRU THE
PERSISTENT TROUGHING OVER THE REGION. PRESENT TIMING HAS ONE
STRONGER SHORTWAVE DROPPING INTO THE REGION WED THEN MORE
SHORTWAVE ENERGY ROTATING AROUND THE DEEP TROUGH/MID LEVEL LOW
OVER THE WESTERN GREAT LAKES FRI/SAT. WITH THE DEEP CYCLONIC
FLOW...COLD CORE OF 850-700MB TEMPS OVER THE REGION...STEEP SFC-
700MB LAPSE...RATES/WEAK INSTABILITY DURING THE AFTERNOON
HOURS...ANY SHORTWAVE WOULD BE CAPABLE OF TRIGGERING SCT -SHRA.
SMALL -SHRA CHANCES MUCH OF THE WED-SAT PERIOD STILL LOOK
REASONABLE UNTIL THE SHORTWAVE TIMING DETAILS CAN BE SORTED OUT.
ANY PRECIP DURING THE WED-SAT WOULD BE SCT AND LIGHT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1149 PM CDT SAT MAY 10 2014
SOME SCATTERED RAIN SHOWERS HAVE DEVELOPED ACROSS SOUTHEAST
MINNESOTA AND WESTERN WISCONSIN AND WILL TRACK QUICKLY TO THE EAST
OVERNIGHT. CONDITIONS ARE MAINLY VFR THOUGH A FEW SPOTS HAVE
BRIEFLY DROPPED TO MVFR WITH VISIBILITY GOING DOWN TO 5SM. BASED
ON THE LOW CHANCES THAT ONE OF THESE SHOWERS WOULD DIRECTLY HIT
RST/LSE...HAVE JUST LEFT IT AS VCSH AND VFR.
THE MAIN FOCUS THEN GOES TO TOMORROW EVENING WHEN IT APPEARS
LIKELY THAT WIDESPREAD THUNDERSTORMS WILL DEVELOP ACROSS THE
REGION AS A WARM FRONT LIFTS NORTH INTO THE REGION. THERE IS SOME
QUESTION ABOUT THE EXACT START UP TIME OF THE CONVECTION...BUT IT
APPEARS MOST LIKELY TO OCCUR AROUND 2Z AT RST AND 4Z AT LSE.
VISIBILITY SHOULD DROP TO IFR OR LOWER IF THE STORMS TRAIN OVER
THE SAME LOCATIONS TOMORROW EVENING. BASED ON THE HIGH CONFIDENCE
THAT WE WILL HAVE RAINS/STORMS...HAVE PUT A PREVAILING TSRA GROUP
IN THE TAFS FOR TOMORROW EVENING.
&&
.HYDROLOGY...
ISSUED AT 310 PM CDT SAT MAY 10 2014
MINOR FLOODING/HIGH WATER CONTINUES ALONG PORTIONS OF THE
MISSISSIPPI RIVER. LATER SUN AFTERNOON INTO MON EVENING WILL BE A
WET PERIOD...WITH POTENTIAL FOR 1 TO 2 OR MORE INCHES OF RAINFALL
DURING THAT PERIOD. THE HEAVIEST RAIN/HIGHEST TOTALS WILL FALL
SUNDAY NIGHT INTO MONDAY MORNING. THESE RAINS COULD HAVE
ADDITIONAL IMPACTS ON BOTH TRIBUTARIES AND THE MISSISSIPPI
RIVER...SLOWING THE RATES OF FALL...PRODUCE ADDITIONAL RISES OR
RENEWED FLOODING. WILL ISSUE AN ESF CONCERNING THE POTENTIAL
HEAVY RAINS SUN NIGHT/MON AND RISING RIVER LEVELS/FLOODING THREAT.
CHECK THE LATEST HYDROLOGIC STATEMENTS FOR THE DETAILS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...HALBACH
SHORT TERM...RRS
LONG TERM....RRS
AVIATION...HALBACH
HYDROLOGY....RRS
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
619 AM EDT SUN MAY 11 2014
.SYNOPSIS...
WEAK HIGH PRESSURE WILL REMAIN IN CONTROL OF THE REGION THROUGH
TUESDAY...WITH MAINLY AFTERNOON SHOWERS AND THUNDERSTORMS BEING
POSSIBLE. A COLD FRONT WILL MOVE INTO THE AREA ON WEDNESDAY AND
THURSDAY PROVIDING INCREASING CHANCES OF SHOWERS AND
THUNDERSTORMS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AN UPPER RIDGE WILL BUILD OVER THE FORECAST AREA TODAY WITH HIGH
PRESSURE OVER THE WESTERN ATLANTIC RIDGING IN AT THE SURFACE.
DESPITE WEAK DYNAMICS...THE SPC WRF AND HRRR ARE IN FAVOR OF
ISOLATED SHOWERS AND THUNDERSTORMS DURING THE AFTERNOON HOURS.
MOISTURE APPEARS HIGHEST IN THE SOUTHEASTERN SECTION OF THE
FORECAST AREA. CONTINUED TO INDICATE ONLY A SLIGHT CHANCE OF
AFTERNOON SHOWERS AND THUNDERSTORMS WITH THE BEST CHANCE
SOUTHEAST. ABOVE NORMAL AFTERNOON HIGHS IN THE UPPER 80S WITH
LIGHT SOUTH/SOUTHWESTERLY WINDS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
CAN NOT RULE OUT SOME SCATTERED LINGERING RAINFALL ACROSS EASTERN
PORTIONS OF THE CWA EARLY TONIGHT...THEN ALL AREAS DRYING OUT BY
MIDNIGHT. ON MONDAY THE UPPER RIDGE OFF THE ATLANTIC TRIES TO
BUILD WESTWARD BACK ACROSS THE AREA. SURFACE WIND FLOW OFF THE
ATLANTIC WILL CONTINUE TO BRING MOISTURE INTO THE REGION. WITH
AFTERNOON TEMPERATURES FORECAST AROUND 90...CAN NOT RULE OUT
ISOLATED TO SCATTERED AFTERNOON SHOWERS OR STORMS. LIMITING FACTOR
WOULD BE THE LACK OF ANY WELL DEFINED SURFACE FRONT. BEST CHANCE
AT THIS TIME WOULD APPEAR TO BE ACROSS THE EASTERN PORTIONS OF THE
CWA CLOSER TO THE SEA-BREEZE FRONT. ANY ACTIVITY SHOULD DIMINISH
AFTER SUNSET. OVERNIGHT LOWS MONDAY NIGHT REMAIN MILD...WITH
READINGS IN THE MIDDLE 60S.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
ONLY MADE MINOR CHANGES IN THE LONGER TERM AT THIS TIME. MODELS IN
GENERAL AGREEMENT EARLY IN THE PERIOD...THEN THE GFS AND ECMWF
DIVERGE ON THE STRENGTH OF A FORECAST UPPER TROUGH BY THE END OF
THE WEEK.
BERMUDA HIGH IN PLACE ON TUESDAY FOR THE REGION...WITH AN UPPER TROUGH
OVER THE MID PART OF THE COUNTRY. ALTHOUGH THE HIGH OFF THE COAST
WILL DOMINATE INTO MID WEEK...INCREASING MOISTURE AND TEMPERATURES
WILL RESULT IN A CHANCE OF A FEW AFTERNOON THUNDERSTORMS TUESDAY.
THE DIURNAL ACTIVITY WILL DIMINISH OVERNIGHT AND THEN THE CHANCE
OF AFTERNOON THUNDERSTORMS INCREASES WEDNESDAY. AS THE NEXT SYSTEM
SLOWLY APPROACHES THE AREA AND MOVES THROUGH ON THURSDAY EXPECT
THE CHANCE OF RAIN TO CONTINUE. HAVE RAISED THE POPS INTO THE
LIKELY CATEGORY FOR THURSDAY...WITH DIMINISHING POPS BEGINNING
THURSDAY EVENING. WILL HAVE TO CONTINUE TO WATCH THE TIMING AND
PROGRESSION OF THE UPPER TROUGH THOUGH. TEMPERATURES AHEAD OF THE
NEXT SYSTEM SHOULD BE ABOVE NORMAL IN THE UPPER 80S TUESDAY AND
WEDNESDAY AND THEN AS CLOUDS AND PRECIPITATION MOVE IN...HIGHS
WILL BE SOMEWHAT COOLER THE REMAINDER OF THE WEEK IN THE UPPER 70S
TO AROUND 80.
&&
.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
EXPECT MAINLY VFR CONDITIONS THROUGH THE PERIOD. WITH LOW DEW
POINT DEPRESSIONS AND PLENTY OF LOW LEVEL MOISTURE IN PLACE...MVFR
CIGS AND VSBYS ARE POSSIBLE THROUGH 12Z. VFR CONDITIONS EXPECTED
AT ALL TERMINALS BY 14Z WITH LIGHT SOUTHWEST WINDS THROUGH THE
DAY. AN UPPER RIDGE WILL BUILD OVER THE REGION TODAY WHICH SHOULD
LIMIT PRECIPITATION. HOWEVER... SOME MODELS ARE INDICATING
AFTERNOON SHOWERS AND THUNDERSTORMS DEVELOPING. CONFIDENCE IN
TIMING AND COVERAGE IS TOO LOW TO INCLUDE IN CURRENT TAF ISSUANCE.
.EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE WEDNESDAY NIGHT
INTO THURSDAY WITH SHARP UPPER TROUGH APPROACHING THE AREA
RESULTING IN SHOWERS AND THUNDERSTORMS.
&&
.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&
$$
Area Forecast Discussion
National Weather Service Lincoln IL
1044 AM CDT Sun May 11 2014
.DISCUSSION...
ISSUED 1044 AM CDT Sun May 11 2014
Warm front continues to lift northward through the region this
morning. Boundary is becoming difficult to analyze, as winds have
become southerly across central Illinois, while the tightest dewpoint
gradient remains further south across central Missouri into far
southern Illinois. Cluster of convection is currently ongoing
north of the warm front over southwest Iowa. We will need to keep
a close eye on these storms as they track along the boundary
today. Some models develop this convection eastward into central
Illinois between 1 pm and 4 pm, while the HRRR continues to take
it more northeastward into northern Illinois, generally tracking
along the 850mb warm front. Since convective evolution remains
uncertain, will not be making any changes to the going forecast at
this time. POPs will be highest across the far N/NW KILX CWA in
closer proximity to the upper front and the potential track of the
Iowa convection. Further south into the warm sector, any storms
that fire south of the I-72 corridor will be much more scattered
in nature, so lower POPs are warranted there.
Barnes
&&
.AVIATION...
ISSUED 700 AM CDT Sun May 11 2014
A warm front lifting north across the area will stall out from
Galesburg to Champaign. Strong to severe storms will be possible
as early as 18-19z, but higher potential will occur as the
afternoon progresses. Timing of storms at each terminal site is
still uncertain, so VCTS was still left in this set of TAFs for
the afternoon into early evening. NCEP 4km WRF output has
scattered storms developing periodically across the area, so
multiple episodes of stormy weather could occur at any site. Any
periods of MVFR will be mainly during any thunderstorms and
primarily associated with visibility dropping during heavy rain.
Forecast soundings indicate cloud levels should remain VFR, even
during thunderstorms. However, brief MVFR conditions from cloud
levels will also be possible during any storms.
Winds will increase from the south by afternoon, with 15G28KT
possible in most areas. The northern terminals of PIA, BMI and CMI
will be closer to the front, so wind direction may be slightly
east of south and a little less gusty, but will still be breezy.
LLWS conditions are expected later tonight as an elevate low level
jet intensifies from SW to NE across the area. Wind direction
looks to be SW with wind speeds of 45kt in the 1200-1500 foot
level.
Shimon
&&
.PREV DISCUSSION...
ISSUED 330 AM CDT Sun May 11 2014
SHORT TERM...Today through Wednesday night
MCS with showers and scattered thunderstorms from I-72 south to
I-64 early this morning with isolated strong to severe storms
with hail and gusty winds of 40-60 mph moving east at 40 mph
toward the Wabash river. Models show these showers and
thunderstorms diminishing by sunrise as warm front lifts northward
across central and into northern IL during today. Kept a chance of
convection today and tonight though best chances northern areas.
SPC has slight chance of severe storms over most of CWA today and
early evening with moderate risk over central/southern IA into se
NE and north-central KS. SPC has slight risk of severe storms nw of
the IL river late Monday afternoon and Monday evening as cold
front approaches the MS river valley. Warmer highs in the 80s
today and Monday and more humid with dewpoints in the 60s.
Highest chances of convection will be Monday night western areas
and eastern IL Tue with passage of cold front. SPC has 5% risk of
severe storms Tue over far eastern IL with passage of cold front
though better chances further east over IN and lower MI.
Models continue to show surface low pressure ejecting ne from
southern MS river valley into the Ohio river valley Wed and qpf
moving back over central and especially eastern IL and have
increase pops on Wed and Wed evening. Large upper level trof
settles into the Midwest during mid week and have temps cooling
below normal by Wed/Thu with highs in the lower 60s and lows in
the 40s Wed night & Thu night.
LONG TERM...Thursday through Sunday
Extended models have been consistent in showing a large upper
level trof over the Great Lakes region and Midwest during mid/late week
and gradually pulls away from IL by Sunday. Below normal
temperatures expected during mid and late week with temps a good
10 degrees below normal. Instability isolated light showers
possible each day especially during the afternoon and early
evening hours until sunset due to upper level trof and a few
disturbances pivoting through the trof.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1026 AM CDT SUN MAY 11 2014
.UPDATE...
ISSUED AT 1019 AM CDT SUN MAY 11 2014
CURRENT STORM COMPLEX OVER WESTERN IOWA IS SLOWLY DECAYING.
HOWEVER...BOUNDARIES FROM THIS COMPLEX ARE INTERACTING WITH THE
SURFACE WARM FRONT AND GENERATING NEW CONVECTION IN SOUTHWEST
IOWA THAT IS MOVING EAST NORTHEAST.
12Z UA ANALYSIS SHOWS A SHARP MOISTURE GRADIENT ACROSS THE AREA
WITH THE 850MB WARM FRONT ROUGHLY INTO SOUTHERN IOWA. STORMS IN
SOUTHWEST IOWA SHOULD GENERALLY MOVE ALONG SAID UPPER FRONT TOWARD
THE AREA THE REMAINDER OF THE MORNING.
NOWCASTING AND VARIOUS TOOLS/TECHNIQUES INDICATE VERY LITTLE IN
THE WAY OF FORCING ACROSS THE AREA THROUGH THE REMAINDER OF THE
MORNING. SHOWERS CANNOT BE RULED OUT DEVELOPING ALONG THE 850MB
WARM FRONT WITH POSSIBLY SOME THUNDER. RAP TRENDS INDICATE THE
850MB FLOW WEAKENING THROUGH MID DAY AND BEGINNING TO BACK WHICH
WOULD RE-FOCUS NEW DEVELOPMENT WEST OF THE AREA THIS AFTERNOON.
&&
.SYNOPSIS...
ISSUED AT 228 AM CDT SUN MAY 11 2014
00Z UPPER AIR ANALYSIS AND WV IMAGERY SHOWED STRONG SHORTWAVE
LIFTING EAST NORTHEAST INTO MINNESOTA WHILE ANOTHER WAVE WAS
ROUNDING THE BASE OF THE TROUGH OVER THE SOUTHWEST CONUS. GULF
MOISTURE FEED ALSO BEGINNING TO DEVELOP ACROSS THE SOUTHERN PLAINS
WITH 10C 85H DEWPOINTS AS FAR NORTH AS KANSAS CITY AT 00Z. AT THE
SURFACE...A FRONTAL BOUNDARY EXTENDED FROM NORTHWEST MISSOURI INTO
SOUTHERN ILLINOIS WITH CONVECTION MAINLY CONFINED ON THE COLD SIDE
OF THE BOUNDARY IN EASTERN MISSOURI AND SOUTHERN ILLINOIS. LATEST
RADAR IMAGERY SHOWED THE STORM CELL THAT DEVELOPED OVER IOWA
COUNTY AROUND MIDNIGHT HAS SINCE MOVED EAST AND DIMINISHED.
AT 2AM...TEMPERATURES WERE IN THE UPPER 50S TO LOWER 60S WITH
DEWPOINTS IN THE MIDDLE 40S TO UPPER 50S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 228 AM CDT SUN MAY 11 2014
FORECAST FOCUS REMAINS ON SEVERE WEATHER POTENTIAL MAINLY THIS
AFTERNOON AND INTO THE OVERNIGHT HOURS.
TODAY...CONVECTION CURRENTLY DEVELOPING OVER SOUTHERN NEBRASKA
AND NORTHERN KANSAS TO LIFT EAST NORTHEAST AND BECOME MORE
WIDESPREAD OVER CENTRAL IOWA AS LLJ STRENGTHENS THIS MORNING AND
WHERE BETTER UPPER LEVEL DIVERGENCE WILL BE FOUND. LATEST HRR MODEL
TRENDS SHOW SCATTERED SHOWERS AND STORMS DEVELOPING MAINLY ACROSS
THE NORTHWEST THIRD OF THE CWA BY EARLY AFTERNOON. WARMING AROUND
925MB SHOULD HELP LIMIT ANY STORM DEVELOPMENT UNTIL THE AFTERNOON OVER
THE CWA. ANY STORM THAT DEVELOPS NORTH OF THE WARM FRONT COULD
BECOME SEVERE WITH MAIN THREATS LARGE HAIL AND DAMAGING WINDS.
DEEP MIXING AND STRONG WAA ALOFT WILL ALLOW FOR HIGHS UPPER 70S
NORTH TO THE MIDDLE 80S IN THE SOUTH BY THE AFTERNOON. INCREASING
DEWPOINTS INTO THE 60S WILL ALSO RESULT IN SOMEWHAT HUMID
CONDITIONS.
TONIGHT...WARM FRONT TO LIFT NORTH OUT OF THE CWA BY 00Z MONDAY. A
COLD FRONT WILL SLOWLY MAKE ITS WAY ACROSS IOWA. THERE IS A
POSSIBLY THAT THERE MAY BE SEVERAL HOURS LATE IN THE EVENING
WHERE THE REGION WILL BE DRY IN THE WARM SECTOR AND WILL PASS ON
THIS CONCERN TO THE NEXT SHIFT. AHEAD OF COLD FRONT MOVING OVER IOWA
...STRONG SOUTHERLY FLOW WILL CONTINUE TO USHER IN RICH GULF
MOISTURE WITH MODEL PWATS IN EXCESS OF 1.6 INCHES OVER CENTRAL
IOWA AND THE NORTHWEST SECTIONS OF THE CWA. EXPECT SUPERCELLS TO
FORM AHEAD OF FRONT OVER CENTRAL IOWA AND PROPAGATE EAST INTO THE
CWA EARLY MONDAY IN A VERY FAVORABLE ENVIRONMENT WITH SBCAPES IN
EXCESS OF 3000 J/KG AND 0-6KM SHEAR VALUES AROUND 40 KTS. MAIN
SEVERE THREATS AT THIS TIME WILL BE VERY LARGE HAIL AND DAMAGING
WINDS. LOCALLY HEAVY RAINFALL WILL ALSO BE POSSIBLE. ANOTHER VERY
MILD NIGHT IN STORE FOR THE REGION WITH LOWS ONLY IN THE MIDDLE
60S TO LOWER 70S.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 228 AM CDT SUN MAY 11 2014
EARLY MONDAY A DEEP UPPER TROF WILL BE LOCATED JUST EAST OF THE
ROCKIES WITH A SURFACE COLD FRONT FROM EASTERN MINNESOTA THROUGH
WESTERN IOWA. THE UPPER TROF AND COLD FRONT WILL MOVE SLOWLY EAST
MONDAY. THE COLD FRONT SHOULD MOVE THROUGH THE MID MISSISSIPPI
VALLEY FROM LATE MONDAY AFTERNOON THROUGH MONDAY EVENING. THE LATE
DAY AND EVENING TIMING OF THE COLD FRONTAL PASSAGE WILL FAVOR
ANOTHER RISK OF SEVERE THUNDERSTORMS FOR THE ENTIRE AREA SINCE THE
AIRMASS AHEAD OF THE FRONT WILL BE QUITE MOIST AND WILL HAVE PLENTY
OF TIME TO HEAT/DESTABILIZE PRIOR TO THE FROPA. HAVE HELD POPS IN
THE CHANCE CATEGORY MONDAY MORNING WITH LITTLE INDICATION OF
FORCING TO SUPPORT THUNDERSTORM DEVELOPMENT. CATEGORICAL POPS
WERE SPREAD EAST ACROSS THE AREA WITH THE BETTER FORCING
ASSOCIATED WITH THE COLD FRONT DURING THE AFTERNOON AND OVERNIGHT
HOURS. THE SEVERE THREAT SHOULD BE DURING THE AFTERNOON AND
EVENING AND CONSIST OF MAINLY LARGE HAIL AND DAMAGING WINDS. THERE
WILL BE LITTLE DIRECTIONAL SHEAR IN THE DEEP SOUTHERLY FLOW AHEAD
OF THE UPPER TROF TO SUPPORT A SIGNIFICANT TORNADIC THREAT. THE
SLOW MOVEMENT OF THE FRONT AND UPPER TROF ALONG WITH PW/S
EXCEEDING 1.5 INCHES WILL FAVOR QPF AMOUNTS OF AN INCH PLUS BY
TUESDAY MORNING NEAR AND EAST OF THE MISSISSIPPI RIVER.
THE LONGER RANGE MODELS ARE PRETTY CONSISTENT ON THE 00Z RUN OF
MOVING THE UPPER TROF INTO THE MISSISSIPPI VALLEY BY MID WEEK AND
CLOSING AN UPPER LOW OFF OVER THE NORTH CENTRAL STATES OR THE
WESTERN GREAT LAKES. THE UPPER LOW THEN LINGERS OVER THE AREA
THROUGH THE END OF THE WEEK. GIVEN THIS SCENARIO THE DEEP CYCLONIC
FLOW WITH THE UPPER LOW WILL KEEP SHOWERY AND COOL WEATHER OVER THE
REGION FOR THE REST OF THE WEEK. BY THURSDAY OR FRIDAY BOTH THE
ECMWF AND GFS SHOW A REINFORCING SHOT OF COOLER AIR MOVING SOUTH
INTO THE MID MISSISSIPPI VALLEY WITH H8 TEMPS AT OR JUST BELOW 0C
SPREADING OVER THE REGION. IF THIS VERIFIES AND THEN WE COULD SEE
LOWS TEMPERATURES IN THE MID TO UPPER 30S...OR COLDER GIVEN GOOD
RADIATIONAL COOLING CONDITIONS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 637 AM CDT SUN MAY 11 2014
GENERALLY VFR CONDITIONS EXPECTED AT ALL TAF SITES THROUGH THE
PERIOD. A WARM FRONT WILL LIFT NORTH OVER THE REGION TODAY
PROVIDING A FOCUS FOR STORM DEVELOPMENT. DAYTIME HEATING COMBINED
WITH LOW LEVEL CONVERGENCE WILL ALLOW FOR ELEVATED SHOWERS AND
THUNDERSTORMS TO DEVELOP GENERALLY ALONG AND NORTH OF THE FRONT
DURING THE LATE MORNING AND EARLY AFTERNOON HOURS. SOME OF THESE
STORMS MAY BECOME SEVERE WITH LARGE HAIL AND STRONG WINDS. HAVE
INCLUDED TS GROUPS FOR ALL BUT THE BRL TERMINAL. WARM FRONT TO BE
NORTH OF THE AREA BY 00Z/12 WITH ADDITIONAL STORM DEVELOPMENT
EXPECTED LATE IN THE TAF PERIOD AS COLD FRONT PUSHES EAST ACROSS
IOWA.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...08
SYNOPSIS...GROSS
SHORT TERM...GROSS
LONG TERM...DLF
AVIATION...GROSS
AREA FORECAST DISCUSSION
NWS WICHITA KS
637 AM CDT SUN MAY 11 2014
...UPDATED FOR 12Z AVIATION DISCUSSION...
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 329 AM CDT SUN MAY 11 2014
FORECAST HIGHLIGHTS FOCUS AROUND SEVERE THUNDERSTORMS LATE THIS
AFTERNOON THROUGH EVENING GENERALLY NORTHWEST OF THE KS TURNPIKE.
STRONG 850-700MB WARM/MOIST ADVECTION ON NOSE OF 50-60 KT LOW-
LEVEL JET IS CURRENTLY PROMOTING NUMEROUS ELEVATED THUNDERSTORMS
TO ERUPT OVER NORTHERN/NORTHEAST KS AND SOUTHERN NEBRASKA.
THINKING ADDITIONAL DEVELOPMENT SOUTH OF THIS CURRENT ACTIVITY IS
UNLIKELY EARLY THIS MORNING GIVEN STOUT ELEVATED MIXED LAYER
BUILDING IN FROM THE SOUTH.
ATTENTION THEN TURNS TO THUNDERSTORM CHANCES LATE THIS AFTERNOON
THROUGH TONIGHT...AS A STRONG COLD FRONT SURGES SOUTHEAST INTO THE
AREA. LATEST GUIDANCE HAS SLOWED DOWN THE FRONTAL PASSAGE BY QUITE
A BIT...AND AS SUCH HAVE SLOWED DOWN EASTWARD MARCH OF
THUNDERSTORMS THROUGH TONIGHT. BEST CHANCES BEFORE MIDNIGHT WILL
BE GENERALLY NORTHWEST OF THE KS TURNPIKE...WITH THOSE CHANCES
GRADUALLY SHIFTING SOUTHEAST AFTER MIDNIGHT. GIVEN STRONG
AFTERNOON HEATING AND STRONG FRONTAL CONVERGENCE AMIDST 60S
DEWPOINTS...THUNDERSTORMS SHOULD DEVELOP RAPIDLY BY MID-LATE
AFTERNOON NORTHWEST OF GREAT BEND--SALINA. AMPLE INSTABILITY/DEEP
LAYER SHEAR WILL PROMOTE LONG-LIVED SUPERCELL STORMS...ESPECIALLY
EARLY ON...CAPABLE OF VERY LARGE HAIL/DAMAGING WINDS AND PERHAPS A
FEW TORNADOES...ALTHOUGH SOMEWHAT HIGHER CLOUD BASES AND THE
POTENTIAL FOR STORMS TO GO LINEAR QUICKLY SHOULD PRECLUDE A
WIDESPREAD TORNADO THREAT. AS STRONG FRONTAL FORCING CONTINUES TO
INCH SOUTHEAST...STORMS WILL LIKELY TRANSITION TO A SQUALL
LINE/BROKEN LINE SEGMENTS DURING THE EVENING...WITH A CONTINUED
THREAT FOR LARGE HAIL/DAMAGING WINDS. THE TORNADO THREAT SHOULD
CONTINUE WELL INTO THE EVENING...GIVEN LOWERING CLOUD BASES AND
STRENGTHENING LOW-LEVEL SHEAR...ESPECIALLY FOR ANY SOUTHERN-MOST
STORM AT THE END OF A LINE AND/OR A STORM THAT IS ABLE TO REMAIN
DISCRETE. OVERALL SEVERE THREAT WILL LIKELY WANE GENERALLY AFTER
MIDNIGHT...ALTHOUGH LOCALLY HEAVY RAIN THREAT WILL CONTINUE GIVEN
MID/UPPER FLOW PARALLEL TO THE COLD FRONT...SUPPORTING TRAINING
STORMS THROUGH THIS ENTIRE EVENT.
THUNDERSTORM CHANCES WILL CONTINUE GENERALLY OVER EASTERN KS
MONDAY. THE LATEST NAM HAS REALLY SLOWED THE FRONT`S EASTWARD
PROGRESSION...WHICH WOULD SUPPORT THE POTENTIAL FOR STRONG/SEVERE
STORMS MONDAY AFTERNOON OVER SOUTHEAST KS...ALTHOUGH THE
LIKELIHOOD OF WIDESPREAD CLOUDS MAY TEND TO LIMIT OVERALL
INSTABILITY. GFS/ECMWF BLOW THE FRONT THROUGH QUICKER ON
MONDAY...WHICH WOULD TEND TO PRECLUDE A SEVERE THREAT. GIVEN THE
EVOLUTION OF THIS SYSTEM AS OF LATE...WOULDN`T BE SURPRISED IF THE
SLOWER NAM VERIFIES.
.LONG TERM...(WEDNESDAY THROUGH SATURDAY)
ISSUED AT 329 AM CDT SUN MAY 11 2014
NO MAJOR CHANGES FROM PREVIOUS FORECAST/THINKING. LONGWAVE TROUGH
ACROSS THE CENTRAL US AT START OF THE PERIOD WILL GRADUALLY
ROTATE/MOVE NE BY SAT. DIFFERENCES BETWEEN GFS/ECMWF BECOME MORE
PRONOUNCED LATE IN THE PERIOD...WITH THE ECMWF NOT AS DEEP WITH
UPPER LOW AND MORE RIDGING ACROSS THE PLAINS. BOTH MODELS HOWEVER
BACKDOOR FRONT INTO AREA ON FRI/SAT. BOTH MODELS ALSO CONTINUE THE
TREND TO DRIBBLE PRECIPITATION OUT WITH VARIOUS RIPPLES IN THE
NORTHWEST FLOW. GIVEN SUCH WEAK IMPULSES AND DIFFICULTY IN TIMING
THEM ACCURATELY IN NW FLOW...WILL CONTINUE THE DRY FORECAST FOR
NOW. TEMPERATURES WILL REMAIN BELOW NORMAL THROUGHOUT THE PERIOD.
-HOWERTON
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 633 AM CDT SUN MAY 11 2014
TOUGH AVIATION FORECAST WITH MVFR CEILINGS THIS MORNING AND TIMING
OF STRONG/SEVERE CONVECTION THIS EVENING AND OVERNIGHT. ANTICIPATE
CEILINGS MAY DECEASE FOR THE FIRST HOUR OR TWO OF FORECAST...BUT
HEATING/MIXING SHOULD CAUSE CLOUDS TO DECREASE/RISE FOR MOST
SITES BY MID MORNING. AXIS OF HIGHEST MOISTURE...KICT-KSLN...MAY
SEE BROKEN VFR CONDITIONS FOR MOST OF THE DAY. VERY GUSTY WINDS
ARE LIKELY THROUGHOUT THE DAY AND INTO THE EVENING AHEAD OF THE
FRONT. TIMING OF FRONT REMAINS PROBLEMATIC. RECENT MODEL RUNS
SUGGEST A BIT QUICKER FRONTAL PASSAGE...SOMEWHERE BETWEEN
YESTERDAYS VERY FAST SOLUTIONS AND THE VERY SLOW 0000 UTC
SOLUTIONS. LATEST HRRR AND 0600 UTC NAM WERE USED FOR TIMING WITH
MINOR ADJUSTMENTS. THIS PUTS CONVECTION INTO KRSL AROUND 21-22
UTC...KICT 06-07 UTC AND KCNU AROUND 08-09 UTC. CONVECTION AT KCNU
WILL BEGIN WELL AHEAD OF THE FRONT. MVFR CEILINGS ARE LIKELY
BEHIND THE FRONT GIVEN SIGNIFICANT COLD AIR ADVECTION AND
LINGERING MOISTURE. -HOWERTON
&&
.FIRE WEATHER...
ISSUED AT 329 AM CDT SUN MAY 11 2014
STRONG/GUSTY SOUTH WINDS IN CONCERT WITH WARM/HOT TEMPERATURES
WILL LEAD TO VERY HIGH TO EXTREME GRASSLAND FIRE DANGER TODAY FOR
GRASSES AT LEAST 85-90 PERCENT CURED. CONSEQUENTLY...WENT WITH A
RED FLAG WARNING FROM LATE MORNING INTO THE EVENING OVER CENTRAL
/SOUTH-CENTRAL KS. SPRING GREEN-UP IS A BIT FURTHER ALONG
GENERALLY EAST OF THE KS TURNPIKE...HENCE NO RED FLAG WARNING
THERE. NUMEROUS THUNDERSTORMS WILL PROGRESS SOUTHEAST ACROSS THE
AREA THIS EVENING--TONIGHT ALONG A STRONG COLD FRONT. MUCH COOLER
AND BREEZY WEATHER ANTICIPATED MONDAY.
ADK
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 90 59 66 42 / 10 70 40 10
HUTCHINSON 91 55 61 41 / 40 70 30 10
NEWTON 89 58 64 41 / 20 80 40 10
ELDORADO 87 63 66 42 / 10 70 60 10
WINFIELD-KWLD 89 66 69 42 / 10 60 60 10
RUSSELL 92 48 55 38 / 60 70 20 10
GREAT BEND 91 49 56 38 / 70 80 20 10
SALINA 91 54 59 40 / 50 80 30 10
MCPHERSON 90 55 60 41 / 40 80 30 10
COFFEYVILLE 88 70 74 47 / 10 40 70 40
CHANUTE 87 69 74 45 / 10 50 60 30
IOLA 86 68 74 45 / 10 50 60 30
PARSONS-KPPF 88 70 74 46 / 10 50 70 30
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 10 AM THIS MORNING TO 10 PM CDT THIS EVENING
FOR KSZ032-033-047>053-067>072-082-083-091>096-098>100.
RED FLAG WARNING FROM NOON TODAY TO 8 PM CDT THIS EVENING FOR
KSZ032-033-047>052-067-068-082-083-091.
&&
$$
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1142 AM EDT Sun May 11 2014
...Forecast Update...
Issued at 1140 AM EDT Sun May 11 2014
A few storms are moving back into southern Indiana late this
morning. Taking a look at models this morning, most of them seem to
be overdoing convection for the morning hours, which makes this
afternoon`s forecast all the more difficult. The HRRR seems to have
the best handle on the current situation, though it is not great
either. Still think the best chance for storms will be west of I-65.
However, cannot rule out isolated storms across east central
Kentucky, so added low pops to this area for the afternoon. The rest
of the forecast remains unchanged.
Issued at 930 AM EDT Sun May 11 2014
The convection from the MCS across southern Indiana this morning
continues to move east. Went ahead and removed pops for the
remainder of the morning hours. A couple of outflow boundaries from
this convection have set up across southern Indiana and central
Kentucky. These may serve as a focus for some strong storms this
afternoon, particularly across southern Indiana which will be closer
to an upper level disturbance. Also removed the fog wording from the
forecast as fog that developed this morning has mixed out.
.SHORT TERM (Now through Monday)...
Issued at 325 AM EDT Sun May 11 2014
The synoptic pattern early this morning features a strong
upper-level trough diving into the southwestern CONUS. In response,
the upper-level flow has begun to amplify a ridge over the Ohio
Valley. This amplification will continue through the short-term
period, leading to much warmer temperatures.
An MCS continue to progress across portions of central Illinois and
western Indiana this morning. This activity is located along the
LLJ axis, which extends from Missouri northeast into IL and IN.
Current trends suggest this activity will remain mostly north of the
region, but could clip our southern IN counties in the pre-dawn
hours. Therefore, will raise pops a bit to account for this
activity.
Otherwise, the MCS will quickly dissipate this morning, leaving
partly to mostly cloudy skies in it`s wake. As thicknesses rise, we
should see temperatures climb well into the 80s today. There is a
consistent signal in both synoptic and hi-res guidance that some
isolated to widely scattered thunderstorms will develop this
afternoon into early this evening, mainly along and west of I-65.
Here, low-level moisture will increase which coupled with
temperatures in the 80s, will yield MLCAPE on the order of 1500-2500
J/kg. As opposed to yesterday, forcing looks rather benign, with no
significant surface future for convection to focus on (although an
outflow boundary from this morning`s MCS could set up across the
region so this will have to be monitored today for a possible
convective focus). As a wave of isentropic ascent spreads northeast
across the region, the lift may be enough to pop some convection
within an uncapped atmosphere. Given the degree of instability,
some isolated stronger storms with small hail and gusty winds will
be possible, but the lack of any significant, convergent surface
feature or upper-level support should help to limit storm
organization.
Any convection this evening will quickly dissipate with the loss of
daytime heating, leading to a dry night. Winds should stay up a bit
as high-level clouds stream by. Thus, think temperatures will stay
up a bit in the mid to upper 60s.
Monday looks quite similar to today. Instability will once again
build in the afternoon, but any forcing will be subtle and
incoherent. Therefore, will continue with just slight chance of
thunderstorms in the afternoon hours, but most will stay dry. Highs
may be a degree warmer than today as the upper-level ridge takes
hold, with highs in the middle to even upper 80s.
.LONG TERM (Monday Night through Saturday)...
Issued at 330 AM EDT Sun May 11 2014
The long term guidance continues to show an active pattern across
North America through the upcoming long term period as a significant
upper level trough axis moves through the Plains states and then
develops into a large upper level gyre over the Great Lakes by the
late part of the work week. A strong cold front associated with the
upper level wave is forecast to push through the region around
midweek bringing a good amount of precipitation to the region along
with a threat of thunderstorms. In the post frontal wake, it
appears that scattered to numerous diurnally driven rain showers
will continue into the latter half of the week along with colder
than normal temperatures. Current data still suggests that we`ll
see temperatures drop to 10 to perhaps as much as 20 degrees below
seasonal normals by late week and into next weekend.
Monday night through Wednesday Night...
Latest model guidance continues to show better forecast convergence
in this time frame with the frontal boundary coming through the
region. It appears that ridging will hold on for Monday night into
most of Tuesday. In fact, Tuesday could be a bit drier and warmer
as the front approaches from the west. Lows Monday night will be
mild with readings generally in the middle to upper 60s. Tuesday is
a bit of a question mark which will depend on clouds and
precipitation in the pre-frontal airmass. The Euro and Canadian GEM
guidance are very bullish on temperatures for Tuesday with highs
climbing into the middle to upper 80s. We are a bit hesitant to
jump on temperatures that quickly, but the multi-model consensus has
trended warmer, so we have raised temperatures into the middle 80s
for much of the region.
Scattered showers and storms will likely develop to our west along
the frontal boundary and push into the region Tuesday afternoon and
evening. The front will slow down a bit and stall slightly on
Wednesday across our region. A strong mid-level vorticity lobe will
advance through the upper trough and likely result in a secondary
area of low pressure which would ride up along the frontal
boundary. This feature would end up producing widespread clouds
and precipitation for the Wednesday and Wednesday night time frame.
For now, have kept much of the forecast trends intact here with the
high probabilities of precipitation from Tuesday evening through
Wednesday evening. Thunderstorms will accompany the front as it
pushes through Tuesday afternoon/evening. However, main dynamical
forcing will be well to the north of our region. Slab forced ascent
combined with abundant height falls aloft should result in adequate
lift for convection. Heavy rainfall, lightning, and gusty winds
appear to be the main threats at this time.
Temperatures Tuesday night will cool into the upper 50s to the lower
60s with highs on Wednesday warming into the mid-upper 60s in the
west and upper 60s to lower 70s in the east. Distinctly cooler
weather will arrive Wednesday night as temperatures fall into the
upper 40s behind the frontal boundary.
Thursday through Saturday...
Surface frontal boundary is expected to be to the east of the region
by Thursday morning with the upper trough axis lagging behind. The
upper trough axis looks to pass over the region Thursday afternoon
and evening which will likely produce scattered rain showers. The
rain chances will likely diminish in areal coverage by
Friday...except perhaps across our northeastern counties where
isolated showers may persist into the day on Friday. The
aforementioned frontal boundary looks to stall out across the deep
south by late Friday into Saturday with several disturbances moving
through the upper trough which will remain across the eastern US.
These disturbances may continue to produce cloudiness along with
isolated showers...especially during the afternoon hours. The
larger weather story of the period will the drop in temperatures
compared to what we have seen of late. The cool northwest flow will
keep temperatures some 10 to as much as 20 degrees below seasonal
normals. Highs Thursday through Saturday will only warm into the
lower 60s in the north with lower to middle 60s across the south.
Overnight lows will generally be in the lower to middle 40s.
Generally stuck close to the Euro bias-corrected temperature
profiles for the this time frame given their exceptional
verification over the last 5-7 days in this forecast time frame.
&&
.AVIATION (12Z TAF Update)...
Issued at 642 AM EDT Sun May 11 2014
An MCS continues to push north of all sites this morning. The cloud
cover associated with this convection has helped to keep any dense
fog rather patchy, with light fog being the general rule. After a
couple more hours of MVFR vsbys at KSDF and IFR at KLEX/KBWG,
conditions will quickly go VFR later this morning.
Guidance has come into a bit better agreement on convection for this
afternoon. Therefore, have gone ahead and added VCTS into KSDF and
KBWG, as timing and coverage have become a bit more clear.
Otherwise, outside of any thunderstorms, expect VFR conditions
through the day with southerly winds around 8-13 knots.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........EER
Short Term.....KJD
Long Term......MJ
Aviation.......KJD
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
927 AM CDT SUN MAY 11 2014
.SOUNDING DISCUSSION...
12Z SOUNDING WAS NOT QUITE AS MOIST AS PREVIOUS WITH THE PRECIP
WATER AT 1.57 INCHES...DOWN FROM 1.85 INCHES. INSTABILITY HAD
INCREASED HOWEVER WITH THE MUCAPE AT 2321 J/KG AND LI -5. ELEVATED
CAP/INVERSION WAS AROUND 550 MB...BUT THIS WILL BE TOO HIGH UP TO
BE AN INHIBITOR FOR DEEP CONVECTION TODAY ONCE TEMPERATURES REACH
THE LOWER 80S. WIND PROFILE FROM SURFACE TO 700 MB WAS SOUTHERLY
15 TO 25 KNOTS WHICH WILL BE FAVORABLE FOR TRANSPORTING DEEPER LOW
LEVEL MOISTURE AND HIGHER PRECIP WATER VALUES BACK INTO THE
FORECAST AREA BY EARLY AFTERNOON AS INDICATED BY THE MODELS. THIS
LOOKS SUPPORTIVE OF THE CURRENT FORECAST PROBABILITY OF 40 PERCENT
FOR SHOWERS AND THUNDERSTORMS. ABOVE 700 MB...WINDS BECOME LIGHT
AND VARIABLE FROM 650 MB TO AROUND 400 MB...AND THIS KNOCKS THE
0-6 KM STORM MOTION DOWN TO 195 DEGREES AT 9 KNOTS. WESTERLY WINDS
INCREASE QUITE A BIT ABOVE 300 MB PEAKING NEAR 85 KNOTS NEAR 150
MB/ 45 KFT. 22/TD
&&
.PREV DISCUSSION... /ISSUED 355 AM CDT SUN MAY 11 2014/
DISCUSSION...
GENERALLY ONLY MINOR CHANGES MADE TO THE FORECAST WITH THIS
PACKAGE AS FORECAST REASONING HASN/T CHANGED AND MODELS ARE
COMING INTO BETTER AGREEMENT CONCERNING THE MID WEEK COLD FRONT.
MUGGY CONDITIONS WILL STICK AROUND THROUGH MID WEEK AS ONSHORE
WINDS CONTINUE TO RESULT IN AN INFLUX OF WARM AND MOIST AIR INTO
THE REGION FROM THE GULF OF MEXICO. THIS WILL KEEP TEMPERATURES...
ESPECIALLY OVERNIGHT...ABOVE NORMAL. AFTERNOON TEMPERATURES
GENERALLY FORECAST TO TOP OUT IN THE MID TO UPPER 80S WITH
OVERNIGHT LOWS STRUGGLING TO DROP BELOW 70 DEGREES.
EXPECT DIURNALLY FORCED CONVECTION EACH AFTERNOON WITH GENERALLY
ISOLATED TO WIDELY SCATTERED COVERAGE. LATEST MODEL RUNS...BOTH
SYNOPTIC AND MESOSCALE...ARE A BIT MORE AGGRESSIVE DEVELOPING
CONVECTION TODAY SO HAVE BUMPED POPS UP TO SOLID CHANCE...AROUND
40 PERCENT...FOR MOST OF THE AREA. LATEST HRRR AND NCEP WRF RUNS
INDICATE SOME CONVECTION DEVELOPING OVER THE NORTHERN GULF BY 14Z
OR 15Z AND THEN MOVING OR SPREADING INLAND BY EARLY AFTERNOON. ON
AVERAGE...QPF SHOULD BE LESS THAN A QUARTER INCH...BUT A FEW
PLACES COULD SEE UP TO AN INCH OF RAIN TODAY IF IMPACTED BY A
HEAVIER STORM OR TWO. SIMILAR CONDITIONS EXPECTED MONDAY...
THOUGH COVERAGE SHOULD BE SLIGHTLY LESS. AM CARRYING 20 TO 30
PERCENT POPS ACROSS THE AREA MONDAY AFTERNOON.
BY TUESDAY...STRONG UPPER TROUGH WILL BE DIGGING INTO THE PLAINS
STATES AND FORCING A COLD FRONT TOWARD THE NORTHERN GULF COAST
REGION. MODELS HAVE COME INTO MUCH BETTER AGREEMENT CONCERNING
BOTH THE AMPLITUDE OF THIS TROUGH AND THE TIMING OF THE SURFACE
COLD FRONT. LOOKS LIKE THE SURFACE FRONT SHOULD PASS THROUGH THE
AREA SOME TIME LATE TUESDAY NIGHT OR EARLY WEDNESDAY MORNING...
WITH COOLER AND DRIER AIR FILTERING INTO THE AREA DURING THE DAY
WEDNESDAY. EXPECT A FAIRLY SIGNIFICANT TEMPERATURE DROP BEHIND THE
FRONT WITH AFTERNOON HIGHS ON WEDNESDAY CURRENTLY FORECAST TO BE
5 TO 10 DEGREES LOWER THAN HIGHS ON TUESDAY. THE REAL DIFFERENCE
WILL BE FELT AT NIGHT...THOUGH...WITH OVERNIGHT LOWS PLUNGING INTO
THE 50S WEDNESDAY NIGHT THROUGH FRIDAY NIGHT FOR MOST OF THE AREA.
NORTHWEST FLOW ALOFT WILL PREVAIL THROUGH THE REMAINDER OF THE
FORECAST PERIOD. MODELS CURRENTLY HINTING AT ANOTHER DISTURBANCE
MOVING INTO THE SOUTHEAST CONUS OVER THE WEEKEND...THOUGH BOTH THE
EURO AND GFS KEEP THE MOISTURE AND FORCING TO THE NORTHEAST OF THE
LOCAL AREA. WITH THIS IN MIND...AM KEEPING A DRY FORECAST THROUGH
THE WEEKEND AT THIS TIME.
AVIATION...
VARIABLE CONDITIONS WERE BEING OBSERVED EARLY THIS MORNING ACROSS
THE FORECAST AREA...RANGING FROM VFR TO LIFR DUE TO CEILINGS BEING
OBSERVED AT SOME OF THE TAF SITES. SOME GENERALLY LIGHT FOG WAS ALSO
IMPACTING A NUMBER OF THE TERMINALS. CONDITIONS ARE EXPECTED TO
IMPROVE TO VFR AT ALL LOCATIONS BY LATE MORNING OR EARLY AFTERNOON.
SCATTERED CONVECTION THIS AFTERNOON WILL BE POSSIBLE AT EACH OF THE
SITES. MVFR TO IFR CEILINGS WILL AGAIN BE POSSIBLE LATE TONIGHT AND
EARLY MONDAY MORNING.
MARINE...
MODERATE SOUTHEAST FLOW WILL CONTINUE ACROSS THE COASTAL WATERS
TODAY AND MONDAY BEFORE EASING ON TUESDAY. A COLD FRONT WILL PUSH
ACROSS THE COASTAL WATERS LATE TUESDAY NIGHT INTO WEDNESDAY WITH
STRONG OFFSHORE FLOW DEVELOPING IN ITS WAKE FROM LATE WEDNESDAY INTO
THURSDAY.
DECISION SUPPORT...
DSS CODE...BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...SLURRY SUPPORT
MONITORING RIVER FLOODING
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED
WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE TO HIGH RISK SVR
AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL
SIGNIFICANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 85 67 86 67 / 40 20 30 20
BTR 86 72 87 70 / 40 20 30 20
ASD 83 71 83 70 / 40 30 20 20
MSY 85 73 83 71 / 40 20 20 20
GPT 84 74 84 72 / 40 20 20 20
PQL 83 69 85 70 / 40 20 20 20
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1048 AM EDT SUN MAY 11 2014
LATEST UPDATE...
UPDATE
.SYNOPSIS...
ISSUED AT 328 AM EDT SUN MAY 11 2014
HIGH PRESSURE WILL SLIP EAST AND ALLOW A FRONTAL SYSTEM TO MOVE
BACK INTO THE AREA TONIGHT. AS THIS SYSTEM MOVES BACK IN SHOWERS
AND THUNDERSTORMS WILL BECOME MORE LIKELY THIS EVENING INTO
TUESDAY EVENING. WARMER AIR WILL MOVE INTO THE AREA FOR THE FIRST
COUPLE OF DAYS OF THE NEW WORK WEEK BEFORE COLDER AIR MOVES IN
BEHIND THE SYSTEM FOR LATE IN THE WEEK.
&&
.UPDATE...
ISSUED AT 1047 AM EDT SUN MAY 11 2014
WILL ISSUE A FCST UPDATE TO LOWER/DELAY THE CHANCE OF RAIN TODAY
AND TO BE MORE OPTIMISTIC WITH CLOUD COVER BASED ON CURRENT
SATELLITE/RADAR TRENDS AS WELL AS LATEST HRRR GUIDANCE. WILL ONLY
CARRY A 20 POP AFTER 5 PM SOUTH OF I-96 WHERE LEADING EDGE OF
BETTER MOISTURE/INSTABILITY WILL BE NOSING IN LATER IN THE DAY.
NEW 12Z NAM SHOWS LLJ FOCUSING FARTHER WEST TONIGHT AND AIMED INTO
IOWA/SRN MN/SW WI. MAY HAVE TO CONSIDER LOWERING POPS TONIGHT AS
WELL BUT WILL WAIT ON ADDITIONAL GUIDANCE.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 328 AM EDT SUN MAY 11 2014
MAIN FOCUS OF THE SHORT TERM CONTINUES TO BE CONVECTIVE TRENDS AND
SEVERE WEATHER POTENTIAL THROUGH THE PERIOD. THERE ARE NO REAL
CHANGES TO THE FCST.
THE QUIETEST PERIOD OF THE SHORT TERM WILL BE THE FIRST PERIOD
TODAY. THE CWFA REMAINS DRY AS OF 07Z THIS MORNING...HOWEVER WE ARE
EXPECTING AT LEAST A FEW LIGHT SHOWERS TO DEVELOP AND ROLL IN LATER
THIS MORNING AND THIS AFTERNOON. THIS WILL OCCUR AS A LLJ OF 35+
KNOTS FUELING A FEW SHOWERS AN ISOLATED THUNDER NEAR THE QUAD CITIES
WILL TRANSLATE EAST THROUGH 18Z. THIS LLJ WILL BE WEAKENING AND WILL
BE BATTLING A FAIR AMOUNT OF DRY AIR INITIALLY OVER THE AREA.
WE WILL SEE A BETTER POTENTIAL OF STORMS DEVELOP THIS EVENING ACROSS
THE SOUTH...AND EVENTUALLY THE CHCS WILL SPREAD NORTH THROUGH THE
NIGHT TONIGHT. A STALLED OUT FRONT CURRENTLY ACROSS IL/IN/OH WILL
STRENGTHEN THIS EVENING AS BETTER WARMTH AND MOISTURE ADVECTS NORTH
OUT OF THE GULF OF MEXICO. WE WILL SEE ANOTHER LLJ INCREASE TO
AROUND 30-35 KNOTS AND NOSE UP INTO THE HEART OF THE CWFA. THE
STORMS SHOULD START OUT AS MAINLY ELEVATED WITH THE FRONT TO OUR
SOUTH INITIALLY. FCST SOUNDINGS SHOW THAT HAIL LOOKS LIKE THE BEST
THREAT WITH A GOOD DEAL OF CAPE IN THE -10C TO -30C LAYER. DAMAGING
WINDS ARE POSSIBLE...HOWEVER A BIT LIMITED DUE TO THE ELEVATED
NATURE OF THE STORMS.
WE EXPECT THAT WAVES OF STORMS WILL REMAIN POSSIBLE THROUGH MON AND
INTO MON EVENING. THE FRONT IS EXPECTED TO GET HELD UP GENERALLY
AROUND THE I-96 CORRIDOR AS IT WILL WAIT FOR A GOOD PUSH IN THE MID
LEVELS AS THE WRN TROUGH STARTS TO LIFT OUT. A 25-30 KNOT LLJ WILL
GENERALLY REMAIN IN PLACE THROUGH THAT PERIOD WHICH WILL HELP TO
FEED THE FORCING AND MOISTURE/WARMTH INTO THE AREA. IT LOOKS LIKE
ALONG OR JUST NORTH OF THE I-96 CORRIDOR WILL SEE THE HIGHEST RAIN
AMOUNTS. WHAT WILL BE INTERESTING IS THE POTENTIAL OF SOME SFC BASED
INSTABILITY ON MON SOUTH OF THE FRONT. THIS COULD ENHANCE THE THREAT
OF SOME SEVERE WX ALONG WITH DEEP LAYER SHEAR VALUES AT OR ABOVE
30.
WE SHOULD SEE A BREAK IN THE MORE WIDESPREAD SHOWER AND STORM
ACTIVITY THEN FOR THE SECOND HALF OF MON NIGHT. WE FINALLY SEE THE
TROUGH OUT WEST DIG ENOUGH THAT THE RIDGE BUILDS IN OUR
NEIGHBORHOOD. THIS WILL PUSH THE WARM FRONT WELL NORTH OF THE AREA
BY TUE.
SHOWERS AND STORMS BECOME MORE NUMEROUS ON TUE ONCE AGAIN AS THE
COLD FRONT AND WHAT LOOKS LIKE A THERMAL TROUGH DEVELOPS INLAND
AND BEGINS TO PUSH THROUGH THE AREA. WE PREFER THE SLOWER FOREIGN
MODEL SOLUTIONS AS THE FRONT LOOKS TO BE FAIRLY PARALLEL WITH THE
UPPER JET. THIS WOULD BRING THE FRONT THROUGH DURING THE DAY WHEN
SOME DIURNAL INSTABILITY WILL BE POSSIBLE. DEEP LAYER SHEAR WILL
ONCE AGAIN BE SUFFICIENT FOR ORGANIZED STORMS WITH VALUES OVER 30
AND INCREASING THAT DAY. FCST SOUNDINGS DO LOOK QUITE CLOUDY WITH A
LOT OF MOISTURE...WHICH WOULD LIMIT THE SEVERE POTENTIAL.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 328 AM EDT SUN MAY 11 2014
LOOKS LIKE A PRETTY UNSETTLED PERIOD WITH COLD AND SHOWERY WEATHER
BY THE END OF THE WEEK UNDER AN UPPER LOW. WILL HAVE TO WATCH
CLOSELY FOR ANY CLEARING OUT ON THURSDAY NIGHT OR FRIDAY NIGHT WHICH
WOULD RESULT IN WIDESPREAD FROST/FREEZE CONDITIONS GIVEN HOW COLD IT
WILL BE.
COLD FRONT PUSHES EAST TUESDAY NIGHT. MODEL DIFFERENCES BETWEEN THE
00Z RUNS OF THE GFS AND ECMWF ARE THE SAME AS THEY HAVE BEEN THE
LAST FEW DAYS WITH THE ECMWF HAVING A SFC LOW FORM ON THE SLOW
MOVING FRONT WHICH BRINGS ANOTHER ROUND OF RAIN FOR WEDNESDAY NIGHT
AND THURSDAY...WHILE THE GFS IS FASTER WITH THE FRONT AND
CORRESPONDINGLY FURTHER EAST WITH THE RAIN. EVEN SO...IT CONTINUES
TO BRING THE CHANCE FOR SHOWERS BY THURSDAY AS SHARP UPPER TROUGH
GOES NEGATIVE TILT THEN CUTS OFF.
UPPER LOW THEN PERSISTS OVER THE CENTRAL GREAT LAKES INTO THE
WEEKEND AND 850 MB TEMPS ARE DOWN TO MINUS 2C TO MINUS 4C ACROSS THE
NORTHERN FORECAST AREA. COULD SEE SOME WET SNOW OR GRAUPEL IN ANY
SHOWERS/CONVECTIVE UPDRAFTS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 732 AM EDT SUN MAY 11 2014
VFR CONDITIONS EXPECTED TODAY AND INTO THIS EVENING. SOME
SCATTERED THUNDERSTORMS WILL BE MOVING IN BY EVENING ALTHOUGH
COVERAGE SHOULD BE LOW UNTIL AROUND MIDNIGHT WHEN SOME MVFR
CONDITIONS DEVELOP IN MORE WIDESPREAD SHOWERS AND THUNDERSTORMS.
WINDS WILL BE SOUTHEAST TODAY AROUND 10 KNOTS GOING SOUTHWEST
TONIGHT.
&&
.MARINE...
ISSUED AT 328 AM EDT SUN MAY 11 2014
WE CONTINUE TO EXPECT THAT WINDS WILL INCREASE OVERNIGHT
TONIGHT AS THE NEXT SYSTEM COMES IN...AND COULD BE EXCEEDING
SMALL CRAFT ADVISORY CRITERIA BY DAYBREAK MONDAY MORNING. THIS IS
NOT A GUARANTEE HOWEVER AS WE WILL HAVE A STABLE SITUATION WHERE
WARMER AIR IS MOVING IN OVER COLDER WATER. THIS POTENTIAL WINDY
PERIOD WOULD LAST INTO TUESDAY MORNING BEFORE CONDITIONS WOULD
IMPROVE A BIT AS A WEAKER GRADIENT MOVES IN WITH THE FRONT.
ANOTHER BURST OF WIND WILL BE POSSIBLE BEHIND THE FRONT TUE EVENING.
&&
.HYDROLOGY...
ISSUED AT 328 AM EDT SUN MAY 11 2014
HYDRO CONCERNS WILL LIKELY RAMP UP BEGINNING SUNDAY AND LASTING INTO
MID WEEK AT LEAST. AN ACTIVE PERIOD IS EXPECTED TO DEVELOP FOR
THE SUNDAY THROUGH TUESDAY TIME FRAME WITH HEAVY RAINS POSSIBLE.
THE BOUNDARY THAT WENT THROUGH THE AREA FRIDAY EVENING WILL COME
BACK NORTH AS A WARM FRONT ON SUNDAY...PULLING GULF MOISTURE WITH
IT. PWAT VALUES RISE TO SLIGHTLY ABOVE 1.50 INCHES...WHICH WOULD
BE 99TH PERCENTILE TYPE OF AMOUNTS.
THE WETTEST PERIOD LOOKS TO COME FROM SUNDAY NIGHT THROUGH
TUESDAY. RAINFALL AMOUNTS OF 1 TO 2 INCHES LOOKS QUITE
POSSIBLE...WITH SOME LOCALLY HEAVIER AMOUNTS LIKELY. SOME RIVERS
UP NORTH ARE ALREADY ABOVE ADVISORY STAGE AND OBVIOUSLY ABOVE
NORMAL. ADDITIONAL RAINFALL WOULD ONLY PUSH STAGES HIGHER. AT THIS
POINT NOT CONSIDERING ANY HYDRO HEADLINES. WE WILL CONTINUE TO
MONITOR.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...MEADE
SYNOPSIS...NJJ
SHORT TERM...NJJ
LONG TERM...OSTUNO
AVIATION...OSTUNO
HYDROLOGY...DUKE/NJJ
MARINE...NJJ
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
739 AM EDT SUN MAY 11 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 454 AM EDT SUN MAY 11 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A SHORTWAVE HEADING SE
TOWARD THE SRN ROCKIES...LEADING THE TROF AMPLIFICATION DOWNSTREAM
OF ADVERTISED BUILDING RIDGE JUST OFF THE W COAST. DEEPENING TROF
AND SHORTWAVE WILL BRING THE NEXT ROUND OF WIDESPREAD WET WEATHER TO
THE UPPER GREAT LAKES...BEGINNING AS EARLY AS LATER TONIGHT. AHEAD
OF THE AMPLIFYING WRN TROF...A SHORTWAVE IS LIFTING THRU THE UPPER
MISSISSIPPI VALLEY. WITH LARGER SCALE RIDGE BUILDING OVER THE
MISSISSIPPI VALLEY/WRN LAKES DOWNSTREAM OF THE DEEPENING WRN
TROF...WAVE IS WEAKENING. LATEST RADAR IMAGERY SHOWS ISOLD/SCT
-SHRA ALONG THE MI/WI BORDER AREA. WITH VERY DRY MASS OVER
THE AREA (NOTE THE VERY DRY COLUMN SAMPLED BY 00Z KGRB SOUNDING)...
PCPN HAS BEEN ON THE LIGHT SIDE WITH MUCH OF IT NOT MORE THAN
SPRINKLES.
SOMEWHAT SURPRISED THAT -SHRA/SPRINKLES ARE HOLDING TOGETHER GIVEN
THE ANTECEDANT DRY AIR MASS AND THE SHORTWAVE/FORCING WEAKENING
UNDER DEVELOPING HEIGHT RISES. IN ANY EVENT...ISOLD/SCT
-SHRA/SPRINKLES SHOULD MOVE NE ACROSS ALL BUT THE FAR ERN FCST AREA
DURING THE MORNING. AFTER THE MORNING HRS...EXPECT A DRY AFTN UNDER
CONTINUED HEIGHT RISES AS RIDGE BUILDS THRU THE WRN GREAT LAKES
DOWNSTREAM OF ROCKIES TROF. YESTERDAY...A NUMBER OF MODELS WERE
SUGGESTING SOME AFTN CONVECTION...ESPECIALLY THE NAM. THAT IDEA WAS
DISREGARDED AS MODELS WERE OVERFORECASTING LOW-LEVEL MOISTURE AND
THUS INSTABILITY. WELL...TODAYS 00Z MODELS RUNS ARE ALMOST ALL
ONBOARD WITH A DRY AFTN AS A RESULT OF CORRECTING THE
MOISTURE/INSTABILITY DOWNWARD. CLOUDS WILL THIN SOME IN THE
AFTN...ALLOWING TEMPS TO RISE WELL INTO THE 60S TO AROUND 70F AWAY
FROM LAKE MODERATION.
AS STRONGER SHORTWAVE BEGINS TO EJECT OUT OF DEEPENING UPPER TROF
DRIFTING TOWARD THE WRN PLAINS TONIGHT...SFC LOW PRES WILL BEGIN TO
LIFT NE THRU THE PLAINS. ALTHOUGH THE EVENING MAY BE DRY...
ESPECIALLY OVER THE NE HALF OF THE FCST AREA CLOSER TO DRY LOW-LEVEL
NE TRAJECTORIES OUT OF SFC HIGH PRES IN ONTARIO...MOST OF THE MODELS
SHOW HIGHER MID LEVEL RH AND PCPN ARRIVING FROM THE SW THRU THE
NIGHT AS WAA/ISENTROPIC ASCENT REGIME SPREADS N. THERE ARE
INDICATIONS OF A SUBTLE SHORTWAVE LIFTING NE INTO THE UPPER
MISSISSIPPI VALLEY LATE TONIGHT...AND THAT WILL FURTHER AID THE
DEVELOPMENT/SPREAD OF SHRA NE INTO UPPER MI DURING THE OVERNIGHT.
NOT MUCH INSTABILITY IS NOTED PER 0-3KM MUCAPE OFF THE NAM/GFS. WITH
A COUPLE HUNDRED J/KG AND SHOWALTER INDEX FALLING JUST BLO 0 OVER
THE FAR SCNTRL LATE TONIGHT IN MOST MODEL GUIDANCE...WILL INCLUDE A
THUNDER MENTION IN THAT AREA LATE TONIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 454 AM EDT SUN MAY 11 2014
AGREEMENT IS HIGH IN OVERALL LARGER SCALE PATTERN FOR THE UPCOMING
WEEK. FLOW IS HIGHLY AMPLIFIED. INITIALY THIS WEEK TROUGH OVER THE
WESTERN CONUS THIS MORNING SLIDES ACROSS THE CENTRAL CONUS. SFC-H85
LOW PRESSURE BEGINS TO FORM TODAY OVER THE SOUTHERN PLAINS AND THIS
LOW LIFTS TOWARD UPPER MISSISSIPPI RIVER VALLEY BY DAYBREAK ON
MONDAY. SFC WARM FRONT SHOULD STAY SOUTH OF UPR MICHIGAN...MAINLY
OVER SOUTHERN/CENTRAL WI ACROSS CENTRAL LOWER MICHIGAN. EASTERLY
LOW-LEVEL WINDS OFF THE COLD GREAT LAKES TO THE NORTH OF THE FRONT
ALONG WITH SHRA/TSRA FIRING ALONG THE FRONT SHOULD KEEP THE WARM
FRONT FROM MOVING INTO UPR MICHIGAN ON MONDAY. WARM FRONT SOUTH OF
HERE ALONG WITH EASTERLY WINDS SHOULD KEEP TEMPS COOLER ON MONDAY
THAN THIS WEEKEND.
H85 WARM FRONT WILL BE IN THE VICINITY THOUGH AND THERE IS MOISTURE
TRANSPORT AT H85-H7 AIMED INTO THE H85 FRONT ALLOWING PWATS OVER 1.5
INCHES OR WELL OVER 200 PCT OF NORMAL TO PUSH NORTHWARD ACROSS UPPER
GREAT LAKES REGION. SHORTWAVE/PV ANAMOLY EMERGING NORTHEAST OUT OF
THE LARGE WESTERN CONUS TROUGH RESULTS IN AREA OF H85-H5 Q-VECTOR
CONVERGENCE SPREADING OVER UPPER GREAT LAKES ON MONDAY. ADDITIONAL
LIFT WILL BE PROVIDED VIA 250MB JET STREAK LIFTING NNE-SSW AHEAD OF
MAIN TROUGH AND ALSO ANOTHER SLIDING WNW-ESE OVER NORTHERN ONTARIO
TOWARD QUEBEC. AT FIRST GLANCE...A LOT OF THINGS ARE FAVORABLE FOR
MULTIPLE PERIODS OF SHOWERS OVER UPR MICHIGAN ON MONDAY. YET...THE
INSTABILITY BOTH ELEVATED /1-6KM MUCAPE/ AND AT THE SFC /MLCAPE/ IS
NOT AS FAVORABLE...WITH GRADIENT OF BOTH TO SOUTH AND SOUTHWEST OF
UPR MICHIGAN THROUGH THE DAY. MODELS DIFFER ON PLACEMENT OF MAXIMUM
MOISTURE ADVECTION AND THIS WILL HAVE DIRECT BEARING ON WHETHER
WESTERN HALF OF CWA OR EASTERN HALF OF CWA SEES MOST RAIN ON MONDAY.
TOUGH TO TELL AT THIS POINT WHICH IDEA WILL BE CORRECT. CORFIDI
VECTORS...BOTH FORWARD AND BACKWARD PROPAGATING...ARE ORIENTED
GENERALLY FROM WEST TO EAST ALONG AND SOUTH OF UPR MICHIGAN...WHICH
LIKELY WILL KEEP PERIODS OF PERSISTENT/HEAVIEST SHRA/TSRA TO SOUTH
OF THE AREA SINCE THAT IS WHERE PRIME GENESIS REGION FOR SHRA/TSRA
WILL BE ALONG THE SFC WARM FRONT. PERFER THE LOOK OF THE ECMWF/UKMET
WHICH KEEP THE TRACK OF HIGHEST QPF ONLY OVER SCNTRL CWA...WITH
LIGHTER AMOUNTS FARTHER NORTH AWAY FM THE SFC WARM FRONT. EVEN
SO...GOING LIKELY POPS SEEM ON TRACK WITH H85 FRONT IN VICINTY.
KEPT SMALL MENTION OF TSRA MAINLY OVER SOUTH HALF INTO THE EASTERN
CWA ALONG NORTH GRADIENT OF ELEVATED INSTABILITY. SPC DAY2 SEVERE
RISK KEEPS SLIGHT PROBABILITIES FARTHER SOUTH...BUT DOES HIGHLIGHT
SOUTHERN TIER OF CWA FOR A 5 PCT RISK.
NEXT SURGE OF SHRA/TSRA DEVELOP MONDAY NIGHT IN RESPONSE TO
SHARPENING TROUGH ALOFT. SFC LOW HAS TRENDED FARTHER NORTH OVER TIME
WITH SFC LOW LIFTING ACROSS WESTERN LK SUPERIOR BY TUESDAY MORNING.
BEFORE THAT...LARGE SCALE ASCENT DEVELOPS DUE TO THE DEEPENING OF
TROUGH ALOFT AND INCREASINGLY DIFFLUENT FLOW ALOFT. THOUGH SFC WARM
FRONT STAYS MAINLY SOUTH OF UPR MICHIGAN...H85 WARM FRONT WILL
PROVIDE MAIN FOCUS FOR SHRA/TSRA MONDAY NIGHT INTO TUESDAY MORNING
AS ANOTHER SURGE OF H85-H7 MOISTURE ADVECTION INTERSECTS THE
BOUNDARY. GFS SEEMS TOO QUICK IN SLIDING THIS WHOLE SYSTEM TO THE
EAST. ECMWF/UKMET AND GEM-NH ARE SLOWER WHICH MAKES SENSE WITH THE
SHARPER TROUGH ALOFT. GIVEN PWATS STILL OVER 200 PCT OF
NORMAL...MODERATE TO HEAVY RAIN COULD OCCUR. DECENT SIGNAL FROM
PREFERRED MODELS THAT HEAVIEST RAIN IMPACTS MAINLY NORTHERN
CWA...INCLUDING THE KEWEENAW PENINSULA. OBVIOUSLY WITH THE SNOWMELT
AND HIGHER RIVER FLOWS THAT ARE CURRENTLY OCCURRING THIS WOULD NOT BE
A GOOD SITUATION IF IT WORKED OUT THIS WAY. SIMILAR TO FORECAST ON
MONDAY...SINCE THE SFC WARM FRONT IS STILL SOUTH OF THE AREA...SFC
SHRA/TSRA ONGOING ALONG THE FRONT COULD VERY WELL IMPACT THIS ENTIRE
SCENARIO...ESPECIALLY AS STORM MOTIONS ARE FORECAST TO BE FROM SW-
NE...SUGGESTING THAT IF CLUSTER OF STORMS FORM FARTHER SOUTH CLOSER
TO SFC WARM FRONT THEY COULD GLIDE OVER EASTERN CWA AND GENERALLY
BYPASS THE WESTERN CWA. CONDIFENCE IN ANY OF THESE TYPE OF DETAILS
REMAINS LOW ATTM.
AS THE SFC LOW LIFTS NORTH OF LK SUPERIOR BY TUESDAY AFTN...EXPECT
DRYING TO SPREAD IN FROM THE WEST...DIMINISHING THEN SHUTTING OFF
ADDITIONAL PRECIPITATION. THOUGH SKIES WILL NOT COMPLETELY CLEAR OUT
AS A LOT OF H85 MOISTURE REMAINS...EVEN SHALLOW MIXING WITH THE WEST
LOW-LEVEL WINDS SHOULD RESULT IN TEMPS PUSHING INTO THE 60S OVER ALL
BUT THE FAR WEST/NORTHWEST AND EAST CWA.
QUESTION FOR THE REST OF THE WEEK IS NOT IF IT WILL BE COOL AND
UNSETTLED BUT TO WHAT DEGREE. ECMWF IS BACK TO SHOWING A VERY DEEP
TROUGH ALOFT THURSDAY INTO FRIDAY...EVEN TO THE POINT OF BECOMING
CLOSED OFF AROUND THURSDAY. PREVIOUS RUNS OF ECMWF HAD BACKED AWAY
FM STRONGER WAVE WRAPPING AROUND THE EDGE OF THE TROUGH LATE THIS
WEEK BUT NOW ITS BACK. GIVEN H85 TEMPS -2C TO -4C FALLING TO BLO -6C
AS THIS WAVE LIFTS OVER THE REGION...CERTAINLY POSSIBLE THAT SOME
SNOW COULD OCCUR THURSDAY INTO FRIDAY FOR ALMOSTL ANYWHERE IN THE
CWA. CONSENSUS OF THAT WRAPPED UP ECMWF SOLUTION ALONG WITH OTHER
AVAILABLE MEDIUM RANGE MODELS RESULTED IN LOW CHANCES ATTM...WITH
MOST MENTION OF SNOW ONLY OCCURRING LATER AT NIGHT INTO THE MORNING
BEFORE BLYR WARMS ENOUGH FOR JUST RAIN. SYSTEM WILL BE SOMETHING TO
KEEP EYE ON AS WE GET LATER INTO THE WEEK. AT THE LEAST EVEN IF WE
GET BY WITHOUT SEEING ANY SNOW...TEMPS WILL FALL TO WELL BELOW
NORMAL VALUES AGAIN. HIGHS MID-LATE WEEK LIKELY WILL STAY IN THE 40S
OVER MUCH OF NORTHERN UPR MICHIGAN CLOSER TO LK SUPERIOR AND ONLY IN
THE 50S OVER SOUTHERN CWA. NIGHTTIME LOWS WILL BE AROUND FREEZING
FOR MUCH OF THE CWA.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 738 AM EDT SUN MAY 11 2014
LINGERING DRY AIR AT THE LOW LEVELS WILL ENSURE VFR CONDITIONS
CONTINUE AT KIWD/KCMX/KSAW INTO THE EVENING HRS EVEN THOUGH A FEW
-SHRA/SPRINKLES WILL MOVE ACROSS THE AREA THIS MORNING. TONIGHT...
NORTHWARD ADVANCING LOW PRESSURE AND WARM FRONT WILL SPREAD SHRA
TOWARD THE UPPER LAKES. THERE IS QUITE A BIT OF UNCERTAINTY IN HOW
FAST PCPN WILL DEVELOP. FOR NOW...OPTED TO HOLD OFF ANY PCPN MENTION
UNTIL THE OVERNIGHT. KIWD HAS THE BEST CHC OF CONDITIONS FALLING TO
MVFR LATE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 454 AM EDT SUN MAY 11 2014
WINDS LESS THAN 20 KTS THROUGH THIS EVENING. WINDS BEGIN TO INCREASE
OVER WESTERN PORTIONS OF LK SUPERIOR LATE TONIGHT AND MORE SO ON
MONDAY AS LOW PRESSURE APPROACHES FROM THE SOUTHWEST. FREQUENT GALE
GUSTS APPEAR LIKELY OVER FAR WEST...SO HAVE ISSUED A GALE WATCH.
WINDS OVER THE REST OF THE LAKE WILL STAY AT OR BLO 30 KTS. WINDS
DIMINISH LATER MONDAY NIGHT AND THEN SWITCH TO THE WEST TO 20-25 KTS
ON TUESDAY. LOW SLOWLY SLIDES TO THE NORTHEAST OF LK SUPERIOR REST
OF THE WEEK...RESULTING IN NORTHWEST WINDS MAINLY STAYING BLO 20 KTS.
&&
.HYDROLOGY...
ISSUED AT 454 AM EDT SUN MAY 11 2014
HIGHS MOSTLY IN THE 60S TODAY WILL RESULT IN ADDITIONAL SNOWMELT
OVER HIGHER TERRAIN OF NORTHERN UPR MICHIGAN. MINIMAL RAIN AMOUNTS
ARE EXPECTED THROUGH MUCH OF TONIGHT...BUT THEN RAIN CHANCES INCREASE
MONDAY/MONDAY NIGHT AND INTO TUESDAY MORNING. THERE IS A POTENTIAL
FOR MODERATE TO HEAVY RAIN OVER THE AREAS THAT ARE STILL MELTING
SNOW...SO THE RECENT HIGHER RIVER LEVELS WILL CONTINUE THROUGH MUCH
OF THE UPCOMING WEEK. THE FLOOD WARNING CONTINUES FOR THE STURGEON
RIVER NEAR CHASSELL...WHILE ADVISORIES ARE IN PLACE FOR THE STURGEON
RIVER NEAR ALSTON...AND THE MICHIGAMME RIVER NEAR WITCH LAKE AND
ALSO NEAR REPUBLIC. IF HEAVIER RAINS MATERIALIZE EARLY THIS WEEK...
ADDITIONAL ADVISORIES AND WARNINGS MAY BE NEEDED. THOSE LIVING NEAR
RIVERS...CREEKS...AND STREAMS SHOULD CONTINUE TO MONITOR THE LATEST
RIVER LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WATCH FROM MONDAY MORNING THROUGH MONDAY EVENING FOR LSZ162.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...ROLFSON
MARINE...JLA
HYDROLOGY...JLA
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
1000 AM CDT SUN MAY 11 2014
.UPDATED...LATEST SATELLITE AND UPPER ANALYSIS SHOWED AN UPPER TROUGH
DIGGING OVER THE ROCKIES...WHICH WAS BRINGING SOME RIDGING OVER THE
REGION. THE SUBTROPICAL JET MAX OVER THE SOUTHERN PLAINS WILL AID IN UPPER
DIVERGENCE FOR TODAY. THIS COMBINED WITH GOOD SOUTHERLY FLOW COMING
OFF THE GULF TO GET SOME CONVECTION GOING THROUGH EARLY THIS
EVENING. AREA RADARS WERE PICKING UP SOME ISOLATED CONVECTION OFF THE
LOUISIANA COAST. THE BEST MOISTURE TRANSPORT WAS NOTED OVER THE
DELTA REGION. AREA SOUNDINGS HAD DECENT SOUTHERLY FLOW UP TO AROUND
600 MB WITH PWATS AROUND 1.7 INCHES. WILL LOOK FOR SOME LOCALLY
HEAVY DOWNPOURS. WE ARE MORE UNSTABLE THIS MORNING WITH CAPES AROUND
3000 AND LI -6. VISIBLE IMAGERY SHOWED SOME DECENT CU FIELDS THIS
MORNING. THE LATEST HRR SHOWS ISOLATED TO SCATTERED CONVECTION
BREAKING OUT EARLIER TODAY. SURFACE ANALYSIS SHOWS DEWPOINTS IN THE
LOWER 70S. SO WE SHOULD BE ABLE TO START EARLIER TODAY WITH THE
DIURNAL CONVECTION. WITH THIS IN MIND HAVE UPPED THE POPS IN THE
EAST SLIGHTLY WITH BETTER INSTABILITY. CURRENT HIGHS IN THE
80S LOOKS TO BE ON TRACK/17/
&&
.AVIATION...CEILINGS HAVE JUST ABOUT ALL RISEN TO MVFR WHILE FOG HAS
JUST ABOUT BURNED OFF AS WELL AS MIXING CONTINUES THIS MORNING. VFR
CEILINGS SHOULD BE THE RULE THIS AFTERNOON WITH SCATTERED SHOWERS
AND THUNDERSTORMS RESULTING IN NO MORE THAN A VICINITY AFFECT OVER
THE MAJORITY OF THE AERODROME. CONVECTION SHOULD DIMINISH BY 00Z
WITH IFR CEILINGS/MVFR VISIBILITIES RETURNING AFTER 06Z./26/
&&
./PREVIOUS DISCUSSION...444 AM CDT SUN MAY 11 2014
.TODAY THROUGH MONDAY NIGHT...
THE ARKLAMISS REGION WILL REMAIN IN A WARM/HUMID AND MAINLY DIURNAL
CONVECTIVE REGIME WITH PRONOUNCED SOUTHERLY LOW LEVEL FLOW. LARGER
SCALE FEATURES AIDING IN DEVELOPMENT OF CONVECTIVE PRECIPITATION ARE
SUBTLE...WITH THE EXIT REGION OF THE SUBTROPICAL JET HELPING TO
ENHANCE UPPER LEVEL DIVERGENCE AND PROVIDE SOME SUPPORT.
EXPECT DAYTIME HEATING TO BE A PRIMARY KEY IN SHOWER/TSTM DEVELOPMENT
LATER TODAY --- THE LATEST HRRR FORECASTS SFC BASED CAPE TO EXCEED
3000 J/KG LATER THIS AFTERNOON IN THE ARKLAMISS DELTA REGION WITH
PRECIPITABLE WATER ~ 1.75 INCHES. WITH LITTLE IN THE WAY OF
CONVECTIVE INHIBITION...ISOLATED TO SCATTERED SHOWER/TSTMS SHOULD
INCREASE IN COVERAGE PER LATEST NEAR TERM GUIDANCE BY AROUND NOON.
RELATIVELY STRONG LOW-LEVEL FLOW MAY SUPPORT STRONG WIND GUSTS IN THE
MORE INTENSE STORMS...BUT NOT EXPECTING MUCH IN THE WAY OF STORM
ORGANIZATION. CONVECTION WILL WANE FAIRLY QUICK AFTER SUNSET WITH
LOSS OF HEATING.
EXPECT A SIMILAR CONVECTIVE SET-UP FOR MONDAY WITH HEATING OF A
WARM/HUMID AIRMASS SUPPORTING ANOTHER ROUND OF MAINLY AFTERNOON
SHOWER/THUNDERSTORMS. SUBTROPICAL JET POSITIONING AND ASSOCIATED
UPPER LEVEL JET DIVERGENCE SHOULD BE A LITTLE BETTER AND SUPPORTIVE
OF GOING WITH HIGHER PRECIP CHANCES OFFERED BY GUIDANCE.
OTHERWISE...RAIN CHANCES SHOULD BE ON THE INCREASE LATE MONDAY NIGHT
IN THE DELTA REGION AS A COLD FRONT BEGINS TO APPROACH FROM THE
NORTHWEST. /EC/
TUESDAY THROUGH NEXT SUNDAY
A COLD FRONT AND ASSOCIATED BAND OF SHOWERS/TSTMS WEDNESDAY WILL
BE MAIN FOCUS THIS PERIOD WITH BELOW NORMAL TEMPERATURES EXPECTED
WED-THURS AND A WARMING TREND FRI-SUN WITH OVERALL DRIER CONDITIONS.
MODEL SUITE FOR THE MEDIUM RANGE CONTINUES TO ALIGN INDICATING AN
AMPLIFIED ERN CONUS RIDGE WITH A DEEP TROUGH ACROSS THE CENTRAL
CONUS AND ATTENDANT SFC LOW IN THE NORTHERN MS VALLEY HELPING SHIFT
AN ELONGATED FRONTAL AXIS TOWARDS AND THROUGH THE LOWER MS VALLEY BY
MID WEEK. THE SLOWER TIMING OF WEATHER ELEMENTS IMPLEMENTED
YESTERDAY LOOKS ON TRACK AS EC REMAINS CONSISTENT WITH CONTINUED
SUPPORT FROM GEM/UKMET WHILE GFS HAS CONTINUED TO SLOW TOWARDS THIS
CAMP.
HAVE INCREASED POPS TUESDAY OVER PREVIOUS VALUES AS A LEAD S/WV
AHEAD OF THE MAIN TROUGH AXIS IS BECOMING MORE REALIZED ALONG THE
FRONTAL AXIS POSITIONED FROM A PADUCAH KY TO MEMPHIS TN TO LAKE
CHARLES LA LINE. GREATEST RAIN CHANCES WILL BE IN W/NW TUESDAY AS
THIS WAVE MOVES OVER THE REGION WHILST SURFACE CONVERGENCE AIDS AS A
LOW-LVL FOCUS. FARTHER EAST, INSTABILITY SHOULD BUILD AND ALLOW FOR
SOME DIURNALLY DRIVEN ISO/SCT TSTMS. THIS ACTIVITY SHOULD WANE
THROUGH TUES EVE WHILE SHOWERS CONTINUE ALONG BOUNDARY IN W/NW AREAS
IN CONJUNCTION OF HIGHER MOISTURE INFLUX/LIFT.
ATTM...HEAVIEST PRECIP AXIS LOOKS TO REMAIN TO OUR NW INTO AR BUT
WILL NEED TO MONITOR FOR NW/W DELTA LATE TUESDAY INTO WEDNESDAY FOR
FLASH FLOODING POTENTIAL BUT CONFIDENCE IS LOW WITH LACK OF DEEPER
FORCING AND NON-COINCIDING HIGH MOISTURE INFLUX. EC/GFS MODERATELY
AGREE THAT FRONT WILL BEGIN TO MOVE THROUGH AREA WED MORNING TO MID
DAY WHILE GREATER QG FORCING MAGNITUDES PIVOT OVER THE REGION ALONG
AND BEHIND THE FRONT WITH INSTABILITY BUILDING IN EAST MS AND INTO AL
WED AFTN. HAVE PLACED GREATEST POPS WED MRNG THROUGH THE EVENING. IF
CURRENT TIMING HOLDS, STRONG/SEVERE DOES NOT LOOK LIKELY FROM LACK OF
FULL DESTABILIZATION AND LACKLUSTER THERMO ENVIRONMENT. TEMPS SHOULD
BE HELD IN CHECK WEDNESDAY BEHIND FRONT AND WITH STRATIFORM
ANAFRONTAL RAIN WITH HIGHS IN THE LOW TO MID 70S. THESE VALUES WERE
CUT FROM MEXMOS BUT FURTHER CUTS MAY NEEDED.
RAIN/TSTMS SHOULD CLEAR OUT BY THURSDAY MORNING ALONG WITH CLOUDS
THROUGH THE DAY BUT TEMPS WILL BE BELOW NORMAL AS AREAS DIP INTO THE
UPPER 40S THURS MORNING WHILE RECOVERING INTO THE MID 70S THAT AFTN.
NW FLOW WILL CONTINUE FRI-SUN WITH OVERALL DRIER CONDITIONS
EXPECTED. HOWEVER, DESPITE AREA UNDER NW FLOW, ENOUGH MOISTURE AND
SOME DESTABILIZATION WITH SUBTLE WAVES MOVING THROUGH COULD TRIGGER
SOME SHOWER ACTIVITY IN THE NORTH BUT CONFIDENCE TO LOW TO PLACE
WEATHER WORDING IN AT THIS TIME. /ALLEN/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 86 68 85 67 / 34 20 34 17
MERIDIAN 87 65 87 62 / 33 18 31 12
VICKSBURG 87 70 87 68 / 34 20 48 29
HATTIESBURG 87 68 88 65 / 40 17 29 12
NATCHEZ 85 69 85 68 / 43 18 56 26
GREENVILLE 87 69 84 67 / 28 20 54 43
GREENWOOD 87 69 86 68 / 28 20 50 29
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
17/EC/ALLEN/26
AREA FORECAST DISCUSSION
NWS RALEIGH NC
655 AM EDT SUN MAY 11 2014
.SYNOPSIS... BERMUDA HIGH PRESSURE OVER THE ATLANTIC WILL EXTEND
WEST OVER THE REGION THROUGH TUESDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 AM SUNDAY...
THE LATEST SURFACE ANALYSIS SHOWED WEAK HIGH PRESSURE OVER CENTRAL
NORTH CAROLINA WITH THE AREA ESSENTIALL PRECIPITATION-FREE AS MID-
LEVEL CLOUDS WERE CLEARING TOWARD THE SOUTHEAST. THINNING HIGH
CLOUDS FROM DEEP CONVECTION WELL UPSTREAM WERE DRIFTING IN FROM THE
NORTHWEST...AND A FEW OF THESE WILL BE NOTICED DURING THE DAY. THE
PRIMARY WEATHER CONCERN FOR TODAY IS THE POTENTIAL FOR ISOLATED TO
SCATTERED DEEP CONVECTION OVER THE FAR SOUTHEAST PART OF CENTRAL
NORTH CAROLINA THIS AFTERNOON INTO THIS EVENING.
THE GFS...NAM...AND RAP ARE DEFINITELY VERY SIMILAR IN THEIR
DEPICTION OF QPF OVER CENTRAL NORTH CAROLINA THIS AFTERNOON INTO THE
EARLY EVENING...WITH THE MEASURABLE LINE MAINLY ALONG AND SOUTH OF A
LINE FROM ABOUT WADESBORO TO TARBORO. IT IS IN THAT AREA WHERE THE
GREATEST PRECIPITABLE WATER VALUES ARE FORECAST THIS AFTERNOON ON
THE GFS AND NAM...TO ABOUT 1.5 INCHES...AND WHERE THERE IS MODEST
LIFT...850MB CONVERGENCE...AND WEAK UPPER DIFFLUENCE. MLCAPE IN THE
LOWEST KM IS FORECAST AROUND 500J/KG...WITH LIFTED INDICES A COUPLE
OF DEGREES OR SO BELOW 0C. BUFR SOUNDINGS AT KGSO...KRDU...AND KRWI
ARE BASICALLY STABLE TO DEEP CONVECTION...BUT THE KFAY BUFR SOUNDING
IS MORE UNSTABLE WITH A MORE LIMITED CAP. CONVECTIVE-ALLOWING MODELS
SUCH AS THE HRRR WRF SUGGESTS ISOLATED-TO-SCATTERED SHOWERS AND
POSSIBLY A THUNDERSTORM DEVELOPING EARLY THIS AFTERNOON AND THEN
WANING WITH SUNSET. LIGHT WIND FIELDS SHOULD MAKE FOR FAIRLY
UNORGANIZED CONVECTION...AND 1000-500MB LAPSE RATES...ONLY TO ABOUT
6C/KM...AND DOWNDRAFT CAPE THAT IS FORECAST BELOW 500J/KG SHOULD
MAKE FOR LIMITED STRONG STORM POTENTIAL.
WILL LEAN TOWARD THE WARMER MAV MOS GUIDANCE ESPECIALLY SINCE IN
MOST PLACES IT IS EXPECTED THAT...EVEN WITH LIGHT WINDS...SUFFICIENT
MIXING SHOULD OCCUR TO MIX OUT DEW POINTS SOME. ALREADY IN PARTS OF
THE NORTHWEST PIEDMONT TO THE TRIANGLE...DEW POINTS HAVE FALLEN
BELOW 60F. HIGHS TODAY 85 TO 90.
TONIGHT...CLEAR TO PARTLY CLOUDY WITH THE POTENTIAL FOR SOME LOW
CLOUDS OR MORE LIKELY FOG IN THE LIGHT WIND FIELD LATE PARTICULARLY
WHERE ANY SHOWERS OCCUR. THE BEST POTENTIAL FOR THESE SHOULD BE
TOWARD THE SOUTHEAST WHERE SREF PROBABILITIES OF FOG ARE HIGHEST
RELATIVE TO THE REST OF CENTRAL NORTH CAROLINA. WILL NOTE PATCHY FOG
IN THE GRIDDED AND WORDED FORECASTS THERE. OVERNIGHT LOWS AROUND 60
TO THE MID 60S.
&&
.SHORT TERM /MONDAY AND MONDAY NIGHT/...
AS OF 300 AM SUNDAY...
SIMILAR CONDITIONS TO TODAY...SUNDAY...ARE EXPECTED MONDAY AND
MONDAY NIGHT WITH HIGHER PRECIPITABLE WATER VALUES CONTINUING OVER
ABOUT THE SOUTHERN TWO TIERS OF COUNTIES IN CENTRAL NORTH
CAROLINA...BETTER LIFT FORECAST IN THE AFTERNOON AND EARLY
EVENING...AND GREATER INSTABILITY COMPARED TO THE REST OF THE AREA.
IN FACT...THE GFS AND NAM MODELS BOTH FORECAST A SLIGHT INCREASE IN
INSTABILITY IN THE SANDHILLS AND SOUTHERN COASTAL PLAIN MONDAY...
WITH LIFTED INDICES APPROACHING -5C IN THE AFTERNOON AND MLCAPE IN
THE LOWEST KM AS HIGH AS JUST OVER 1000J/KG. DOWNDRAFT CAPE IS ALSO
GREATER ON THE GFS WITH SLIGHTLY BETTER 1000-500MB LAPSE RATES...
CLOSER TO 6.5C/KM. THE BUFR SOUNDING FROM THE NAM TOWARD KFAY IS
MORE UNSTABLE MONDAY COMPARED TO SUNDAY...WHILE THE GFS BUFR
SOUNDING HAS JUST A SLIGHTLY BETTER CAP BETWEEN 700MB AND 850MB.
GUIDANCE POPS AND QPF ARE ONCE AGAIN VERY SIMILAR ON THE NAM AND THE
GFS...AND WILL NOTE THE POTENTIAL FOR ISOLATED-TO-SCATTERED
AFTERNOON AND EARLY EVENING SHOWERS AND THUNDERSTORMS IN AN AREA
VERY SIMILAR TO THAT FORECAST TODAY...EXCEPT EXPANDED WEST AND NORTH
EVER SO SLIGHTLY. BUFR SOUNDINGS TOWARD THE TRIAD AND KRDU STILL
SEEM A LITTLE TOO STABLE FOR DEEP CONVECTION. WILL CURRENTLY REFRAIN
FROM THE MENTION OF ANY STRONG STORMS FOR NOW IN THE HWO SO AS TO
MONITOR INSTABILITY AND MOISTURE TRENDS...AND AS ANY DEEP CONVECTION
SHOULD STILL BE FAIRLY UNORGANIZED.
1000-850MB THICKNESSES ARE WARMER MONDAY COMPARED TO TODAY AS
HEIGHTS ALOFT RISE...ENOUGH FOR HIGHS ABOUT TWO OR THREE DEGREES
WARMER MONDAY. OVERNIGHT MONDAY...WILL AGAIN NOTE THE POTENTIAL FOR
PATCHY FOG LATE...MAINLY SOUTH...IN A CONTINUED FAIRLY LIGHT WIND
FIELD. THIS IS SIMILAR TO THE SREF ORIENTATION OF LOW VISIBILITY
PROBABILITIES IN CENTRAL NORTH CAROLINA LATE MONDAY NIGHT. LOWS
MONDAY NIGHT MOSTLY LOWER TO MID 60S.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 300 AM SUNDAY...
TUESDAY AND WEDNESDAY: THIS PERIOD WILL START WITH RIDGING ALOFT AND
A BERMUDA HIGH OFF THE COAST...RESULTING IN WARM MOIST RETURN FLOW
INTO THE AREA. THE APPROACHING COLD FRONT WILL HELP PUSH THE RIDGE
OUT OF THE AREA LATE WEDNESDAY...WITH CONTINUED SOUTHERLY FLOW. THE
INCREASING TEMPERATURES AND MOISTURE WILL RESULT IN THE CHANCE FOR
MAINLY SCATTERED DIURNAL SHOWERS AND STORMS TO DEVELOP...ALTHOUGH
WITH THE LACK OF UPPER LEVEL FORCING...THE CHANCE OF SEVERE STORMS
CONTINUES TO BE LOW. OTHERWISE...EXPECT MAINLY DRY CONDITIONS. HIGHS
GREATEST ON TUESDAY...UPPER 80S TO AROUND 90 DEGREES...DECREASING
SLIGHTLY FOR WEDNESDAY...IN THE MID TO UPPER 80S. OVERNIGHT LOWS IN
THE MID 60S.
WEDNESDAY NIGHT THROUGH SATURDAY: THOUGH THERE ARE STILL TIMING
DIFFERENCES BETWEEN THE MODELS WITH THE APPROACHING LOW PRESSURE
SYSTEM AND ASSOCIATED COLD FRONT...THEY HAVE COME INTO BETTER
AGREEMENT OVER THE PAST FEW MODEL RUNS. THE LATEST MODEL RUNS
INDICATE THE BEST CHANCES FOR SHOWERS AND STORMS ON THURSDAY AFT/EVE
AS THE FRONT BEGINS PUSHING THROUGH THE AREA. CONFIDENCE IS
GRADUALLY INCREASING. EXPECT THE SHEAR AND INSTABILITY TO INCREASE
AS THE FRONT APPROACHES...AND WITH THE FORCING PRESENT...THE THREAT
FOR STRONG TO SEVERE STORMS EXISTS...WITH THE BEST POTENTIAL
INDICATED IN THE SANDHILLS AND COASTAL PLAIN. THERE IS STILL SOME
UNCERTAINTY REGARDING STORM INTENSITY AT THIS TIME GIVEN THE
DEPENDENCE ON FROPA TIMING AND THE MODEL DIFFERENCES IN THAT
REGARD...SO WILL CONTINUE TO MONITOR THE EVOLUTION OF THIS SYSTEM
AND WILL KEEP THE CURRENT WORDING IN THE HWO. EXPECT SHOWER AND
THUNDERSTORM CHANCES TO TAPER OFF BEHIND THE FRONT. TEMPERATURES
WILL DECREASE THROUGH THE PERIOD. HIGHS IN THE MID 70S TO LOW 80S
THURSDAY DOWN TO LOW/MID 70S SATURDAY. LOWS IN THE MID 50S TO AROUND
60 DEGREES THURSDAY NIGHT DOWN TO THE LOW TO MID 50S TO START THE
WEEKEND.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
AS OF 655 AM SUNDAY...
VFR CONDITIONS WILL BE THE RULE THROUGH THE 12Z VALID TAF PERIOD.
EXPECT A FEW LOCATIONS...NOTABLY TOWARD THE TRIAD...TO EXPERIENCE
MVFR CONDITIONS EARLY THIS MORNING...AND EVEN IFR BRIEFLY...WHERE
THE MOST RAIN OCCURRED IN CENTRAL NORTH CAROLINA SATURDAY. DURING
THIS AFTERNOON TOWARD KFAY...TO JUST EAST OF KRWI...ANTICIPATE
ISOLATED-TO-SCATTERED SHOWERS AND A THUNDERSTORM OR TWO IN BETTER
MOISTURE AND INSTABILITY. ANY SHOWERS SHOULD DIMINISH QUICKLY WITH
THE APPROACH OF SUNSET AND THE LOSS OF DAYTIME HEATING. WHILE
BOUNDARY LAYER WINDS ARE LIGHT...BOTH THE GFS AND NAM GUIDANCE
SUGGESTS SURFACE WINDS VEERING THIS MORNING AND THEN BECOMING
ABRUPTLY SOUTHERLY OVERALL BY LATE TODAY. LATE TONIGHT...THERE
SHOULD BE AREAS OF MVFR CONDITIONS IN LIGHT FOG...WITH THE BEST
CHANCE OF CONDITIONS BEING IFR FOR A PERIOD TOWARD KFAY WHERE LOW-
LEVEL MOISTURE WILL BE HIGHER AND WHERE...AGAIN...ISOLATED-TO-
SCATTERED SHOWERS SHOULD OCCUR THIS AFTERNOON INTO THE EVENING.
BEYOND THE 12Z VALID TAF PERIOD...DURING THE WEEK THERE SHOULD BE
INCREASING PROBABILITIES EACH DAY FOR LATE NIGHT AND EARLY MORNING
LOW CLOUDS AND/OR FOG. AGAIN TUESDAY MORNING IT WOULD SEEM THE
BETTER CHANCES OF SUCH WILL BE WHERE ANY AFTERNOON SHOWERS
OCCUR...SUCH AS TOWARD KFAY AND POSSIBLY KRWI. TUESDAY THROUGH
THURSDAY THE CHANCES FOR SHOWERS AND THUNDERSTORMS GRADUALLY
INCREASE AND SPREAD FROM WEST-TO-EAST ACROSS CENTRAL NORTH CAROLINA.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...CBL
NEAR TERM...DJF
SHORT TERM...DJF
LONG TERM...KCP
AVIATION...DJF
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
623 AM EDT SUN MAY 11 2014
.SYNOPSIS...
A DISSIPATING FRONTAL BOUNDARY WILL BRING A CHANCE OF RAIN THIS
AFTERNOON INTO EVENING. HIGH PRESSURE OFFSHORE WILL MAINTAIN WARM
TEMPERATURES THROUGH THE MIDDLE OF THE UPCOMING WEEK. A CHANCE OF
RAIN WILL ARRIVE LATE IN THE WEEK AS A COLD FRONT CROSSES THE
COAST FRIDAY. COOLER TEMPERATURES WILL PREVAIL INTO NEXT WEEKEND
IN WAKE OF THE FRONT.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 623 AM SUNDAY...TRIMMED RAIN CHANCES INTO MORNING AS
ACTIVITY HAS SHIFTED OVER THE OUTER COASTAL WATERS. LATEST
SATELLITE TRENDS POINT TO GOOD SURFACE HEATING TODAY...AND THIS
MAY SET THE STAGE FOR CONVECTION INTO THE AFTERNOON...AS LOW AND
MID LEVEL MOISTURE REMAINS AVAILABLE. ADJUSTMENTS WILL BE MADE TO
SKY COVER AS WELL TO REDUCE CLOUD COVERAGE IN THE EARLY GOING. THE
PREVIOUS EARLY MORNING DISCUSSION FOLLOWS.
ON-BOARD VAPOR SENSORS FROM SPACE SHOW A PLUME OF ELEVATED
PRECIPITABLE WATER DRAWING NE INTO SC AHEAD OF AN APPROACHING BUT
DECAYING FRONTAL SYSTEM EARLY THIS MORNING. MOSAIC RADAR
ANIMATIONS ARE PICKING UP ISOLATED RETURNS OVER THE EASTERN 1/3RD
OF SC AND VERY SE NC...AND THIS ACTIVITY APPEARS TO BE LINKED WITH
A DISTURBANCE ALOFT TRACKING OVERHEAD OF COLUMBIA SC CURRENTLY.
SURFACE ANALYSIS SHOWS A FRONTAL BOUNDARY OVER THE MID-
ATLANTIC...WITH LITTLE IDENTITY SEEN INTO THE CAROLINAS.
TIME-HEIGHT ANALYSIS SHOWS READILY AVAILABLE MOISTURE MUCH OF THE
DAY THROUGH ABOUT 15 KFT. FORECAST SOUNDINGS DEPICT A WEAKLY
FORCED BUT MODERATELY UNSTABLE AIR-MASS TODAY. SURFACE HEATING
THIS AFTERNOON WILL INTERACT WITH PWAT VALUES AROUND 1.5". RECENT
SATELLITE TRENDS SUGGEST DIFFERENTIAL HEATING THROUGH MORNING MAY
ALSO PLAY A ROLE IN TRIGGERING CONVECTION LATER TODAY. SURFACE
OUTFLOWS IN THE RELATIVELY MOIST AIR-MASS WILL ALSO FAVOR MORE
INITIATION. CONVECTIVE MODE OBSERVATIONS SO FAR SHOW PULSE AND LOW
TOP SHOWERS CONGRUENT WITH HIGH PWAT LOW BULK-SHEAR REGIMES.
LOSS OF DIURNAL HEATING AND EXITING IMPULSES ALOFT WILL BRING A
DIMINISHING TREND IN CONVECTION BY LATE EVENING. MINIMUM TEMPS
INTO EARLY MONDAY MIDDLE 60S INLAND TO UPPER 60S NEAR THE COAST.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 330 AM SUNDAY...MID TO UPPER RIDGE WILL BE BUILDING BACK UP
THROUGH THE SOUTHEAST AS BERMUDA HIGH CONTINUES TO PRODUCE A
MOIST SOUTHWESTERLY RETURN FLOW EARLY TO MID WEEK. GRADIENT
REMAINS FAIRLY WEAK THROUGH THE PERIOD WHICH SHOULD ALLOW SEA/LAND
BREEZE TO DOMINATE. ALTHOUGH CONVERGENCE ALONG THE SEABREEZE
SHOULD PRODUCE SOME CU DEVELOPMENT...THERE SHOULD BE ENOUGH DRY AIR AND
SUBSIDENCE ALOFT TO LIMIT SHOWER ACTIVITY. CAN NOT COMPLETELY RULE
OUT AN ISOLATED SHWR OR TWO...BUT WILL MOST LIKELY KEEP POPS
SILENT. MOISTURE PROFILES ALSO CONTINUE TO SHOW UPPER LEVEL
MOISTURE AND THEREFORE MAY SEE SOME CIRRUS STREAMING ACROSS THE
AREA IN WESTERLY FLOW ABOVE H40.
AS FOR TEMPS...THE DECENT RIDGE ALOFT WILL KEEP H5 HEIGHTS AROUND
588 DEM. MAY SEE A SOME CLOUDS BLOCKING THE SUN AT TIMES BUT
OVERALL EXPECT WARM START TO EACH DAY WITH OVERNIGHT TEMPS
REMAINING CLOSER TO 70...LEADING TO TEMPS WELL INTO THE 80S MOST
PLACES WITH STRONGER MAY SUNSHINE.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 330 AM SUNDAY...MID TO UPPER RIDGE REMAINS AMPLIFIED UP
THE EAST COAST AS TROUGH DIGS THROUGH THE MISSISSIPPI VALLEY
WEDNESDAY. SFC HIGH MOVING OFF THE NEW ENGLAND COAST BEGINS TO
DOMINATE WITH MORE OF NORTH TO SOUTH ELONGATED HIGH PRESSURE
SYSTEM DOWN INTO THE CARIBBEAN. THIS WILL HELP THE WINDS BACK TO A
MORE S-SE FLOW. THE DEEPENING MID TO UPPER TROUGH WILL PUSH
EASTWARD DISPLACING THE RIDGE EAST AND PUSHING A COLD FRONT EAST
INTO THE CAROLINAS ON THURS. AT THE SAME TIME AN IMPULSE WILL RIDE
UP AROUND THE ATLANTIC RIDGE FROM THE BAHAMAS AND MAY ADD TO THE
OVERALL MOISTURE REACHING INTO THE CAROLINAS ON THURS. EXPECT
CONVECTION DEVELOPMENT ALONG AN AHEAD OF THIS COLD FRONT AS IT
MOVES EASTWARD REACHING THE COAST THURS NIGHT INTO FRI MORNING.
WILL CONTINUE WITH MAIN FOCUS OF CONVECTION ON THURS INTO THURS
NIGHT.
ONCE THE FRONT MOVES THROUGH BY FRIDAY DRIER AND COOLER AIR WILL
MOVE IN WITH 850 TEMPS DROPPING FROM AROUND 15 C WED AFTN DOWN TO
ABOUT 5 C BY SAT MORNING. H5 HEIGHTS WILL DROP AROUND 20 DEM BY
SAT MORNING. OVERALL EXPECT COOLER WEATHER HEADING INTO NEXT
WEEKEND. TEMPS WILL RUN SEVERAL DEGREES ABOVE NORMAL TO START
REACHING WELL INTO THE 80S ON WED. THE DEWPOINT TEMPS WILL BE IN
THE MID 60S AHEAD OF THE FRONT BUT WILL DROP INTO THE 40S BY THE
WEEKEND WITH TEMPS SEVERAL DEGREES BELOW NORMAL. EXPECT HIGH TEMPS
ONLY IN THE LOWER TO MID 70S FOR THE WEEKEND.
&&
.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
AS OF 06Z...RADAR IMAGERY SHOWS SOME SHOWERS OVER SOUTH CAROLINA
ASSOCIATED WITH AN UPPER DISTURBANCE. THE LATEST HRRR RUNS DISSIPATE
MUCH OF THIS ACTIVITY BEFORE IT REACHES NC. PERIODS OF MVFR/IFR
CIGS/VSBYS IN THE EARLY MORNING HOURS...AS THIS MOIST LOW LEVEL
ENVIRONMENT HAS PROVEN TO BE CONDUCIVE FOR FOG/STRATUS. GUIDANCE
FAVORS IFR STRATUS AND REDUCED VSBYS AT KFLO/KLBT. TEMPO IFR
CIGS/VSBYS CANNOT BE RULED OUT ALONG THE COAST AS WELL. ISOLATED
CONVECTION IS POSSIBLE LATER TODAY WITH SURFACE HEATING AS THE LOW
LEVELS MOISTEN. THE SEA BREEZE WOULD LIKELY BE THE FOCUS FOR ANY
SHOWER ACTIVITY...WITH THE BEST CHANCES AT THE INLAND TERMINALS
LATER THIS AFTERNOON. WILL MAINTAIN VCSH ATTM SINCE COVERAGE WILL
BE SPOTTY AT BEST. SOUTHWEST WINDS 5-10 KTS WILL BECOME SOUTH
AROUND 10 KTS IN THE AFTERNOON AS THE SEA BREEZE PUSHES INLAND.
EXTENDED OUTLOOK...EARLY MORNING IFR FG/STRATUS IS POSSIBLE THROUGH
THE EXTENDED PERIOD...MAINLY INLAND TERMINALS. OTHERWISE VFR.
CHANCE OF SHOWERS/TSTMS MONDAY...MAINLY LATE WEDNESDAY INTO THURSDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 623 AM SUNDAY...MANAGEABLE MARINE CONDITIONS EXPECTED TODAY
AS A WEAK COLD FRONT N AND W OF THE WATERS DISSIPATES. THIS WILL
LEAVE A LIGHT SW WIND FLOW ACROSS THE WATERS THROUGH TONIGHT. SEAS
GENERALLY 2-3 FEET...IN A MIX OF SSW WAVES 1-2 FEET EVERY 4-5 SEC
AND SE WAVES 1-2 FT EVERY 7-8 SECONDS. ISOLATED TSTMS ARE POSSIBLE
NEAR SHORE THIS AFTERNOON INTO THIS EVENING...AND THE MOTION WILL
BE FROM SW TO NE.
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 330 AM SUNDAY...SOUTHERLY FLOW AROUND BERMUDA HIGH WILL
CONTINUE THROUGH EARLY NEXT WEEK. EXPECT S-SW WINDS 10-15 KTS
THROUGH THE PERIOD...WITH LITTLE FLUCTUATION IN STRENGTH OR
DIRECTION EITHER DAY. THESE WINDS PLUS THE PERSISTENT FETCH AROUND
THE OFFSHORE HIGH PRESSURE WILL CREATE 2-3 FT SEAS EACH DAY...WITH
A WAVE SPECTRUM COMPRISED OF A SOUTHERLY 4-5 SEC WIND WAVE AND A
LOW-AMPLITUDE SE GROUND SWELL.
LONG TERM /WEDNESDAY THROUGH THURSDAY/...
AS OF 330 AM SUNDAY...HIGH PRESSURE BECOMES MORE ORIENTED NORTH TO
SOUTH FROM THE WATERS OFF OF NEW ENGLAND COAST DOWN TO THE LOCAL
WATERS OFF THE SOUTHEAST COAST THROUGH MID WEEK. THE FLOW AROUND
THE HIGH WILL REMAIN ORIENTED NORTH TO SOUTH WITH WINDS S-SE TO
START AROUND 10 TO 15 KTS. BY THURSDAY...GRADIENT TIGHTENS AS
DIGGING MID TO UPPER TROUGH PUSHES A COLD FRONT EAST INTO THE
CAROLINAS. THIS WILL PRODUCE AN INCREASE IN WINDS UP AROUND 15
KTS. IN TURN...YOU CAN EXPECT AN INCREASE IN SEAS UP FROM AROUND 2
TO 3 FT EARLY WED TO 3 TO 4 FT BY THURS NIGHT. BEST SHOT OF
SHOWERS AND THUNDERSTORMS WILL COME LATE THURS ASSOCIATED WITH
COLD FRONT.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...MJC
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...MJC/BJR
MARINE...
AREA FORECAST DISCUSSION...CORRECTED
NWS WILMINGTON NC
603 AM EDT SUN MAY 11 2014
.SYNOPSIS...
ATLANTIC HIGH PRESSURE WILL MAINTAIN ABOVE NORMAL TEMPERATURES
THROUGH THE MIDDLE OF THE WEEK. A COLD FRONT WILL APPROACH FROM
THE WEST ON THURSDAY...CROSSING THE AREA BY FRIDAY. COOLER
TEMPERATURES WILL FOLLOW FOR NEXT WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 4 AM SUNDAY...ON-BOARD VAPOR SENSORS FROM SPACE SHOW A PLUME
OF ELEVATED PRECIPITABLE WATER DRAWING NE INTO SC AHEAD OF AN
APPROACHING BUT DECAYING FRONTAL SYSTEM EARLY THIS MORNING. MOSAIC
RADAR ANIMATIONS ARE PICKING UP ISOLATED RETURNS OVER THE EASTERN
1/3RD OF SC AND VERY SE NC...AND THIS ACTIVITY APPEARS TO BE
LINKED WITH A DISTURBANCE ALOFT TRACKING OVERHEAD OF COLUMBIA SC
CURRENTLY. SURFACE ANALYSIS SHOWS A FRONTAL BOUNDARY OVER THE MID-
ATLANTIC...WITH LITTLE IDENTITY SEEN INTO THE CAROLINAS.
TIME-HEIGHT ANALYSIS SHOWS READILY AVAILABLE MOISTURE MUCH OF THE
DAY THROUGH ABOUT 15 KFT. FORECAST SOUNDINGS DEPICT A WEAKLY
FORCED BUT MODERATELY UNSTABLE AIR-MASS TODAY. SURFACE HEATING
THIS AFTERNOON WILL INTERACT WITH PWAT VALUES AROUND 1.5". RECENT
SATELLITE TRENDS SUGGEST DIFFERENTIAL HEATING THROUGH MORNING MAY
ALSO PLAY A ROLE IN TRIGGERING CONVECTION LATER TODAY. SURFACE
OUTFLOWS IN THE RELATIVELY MOIST AIR-MASS WILL ALSO FAVOR MORE
INITIATION. CONVECTIVE MODE OBSERVATIONS SO FAR SHOW PULSE AND LOW
TOP SHOWERS CONGRUENT WITH HIGH PWAT LOW BULK-SHEAR REGIMES.
LOSS OF DIURNAL HEATING AND EXITING IMPULSES ALOFT WILL BRING A
DIMINISHING TREND IN CONVECTION BY LATE EVENING. MINIMUM TEMPS
INTO EARLY MONDAY MIDDLE 60S INLAND TO UPPER 60S NEAR THE COAST.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 330 AM SUNDAY...MID TO UPPER RIDGE WILL BE BUILDING BACK UP
THROUGH THE SOUTHEAST AS BERMUDA HIGH CONTINUES TO PRODUCE A
MOIST SOUTHWESTERLY RETURN FLOW EARLY TO MID WEEK. GRADIENT
REMAINS FAIRLY WEAK THROUGH THE PERIOD WHICH SHOULD ALLOW SEA/LAND
BREEZE TO DOMINATE. ALTHOUGH CONVERGENCE ALONG THE SEABREEZE
SHOULD PRODUCE SOME CU DEVELOPMENT...THERE SHOULD BE ENOUGH DRY AIR AND
SUBSIDENCE ALOFT TO LIMIT SHOWER ACTIVITY. CAN NOT COMPLETELY RULE
OUT AN ISOLATED SHWR OR TWO...BUT WILL MOST LIKELY KEEP POPS
SILENT. MOISTURE PROFILES ALSO CONTINUE TO SHOW UPPER LEVEL
MOISTURE AND THEREFORE MAY SEE SOME CIRRUS STREAMING ACROSS THE
AREA IN WESTERLY FLOW ABOVE H40.
AS FOR TEMPS...THE DECENT RIDGE ALOFT WILL KEEP H5 HEIGHTS AROUND
588 DEM. MAY SEE A SOME CLOUDS BLOCKING THE SUN AT TIMES BUT
OVERALL EXPECT WARM START TO EACH DAY WITH OVERNIGHT TEMPS
REMAINING CLOSER TO 70...LEADING TO TEMPS WELL INTO THE 80S MOST
PLACES WITH STRONGER MAY SUNSHINE.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
AS OF 330 AM SUNDAY...MID TO UPPER RIDGE REMAINS AMPLIFIED UP
THE EAST COAST AS TROUGH DIGS THROUGH THE MISSISSIPPI VALLEY
WEDNESDAY. SFC HIGH MOVING OFF THE NEW ENGLAND COAST BEGINS TO
DOMINATE WITH MORE OF NORTH TO SOUTH ELONGATED HIGH PRESSURE
SYSTEM DOWN INTO THE CARIBBEAN. THIS WILL HELP THE WINDS BACK TO A
MORE S-SE FLOW. THE DEEPENING MID TO UPPER TROUGH WILL PUSH
EASTWARD DISPLACING THE RIDGE EAST AND PUSHING A COLD FRONT EAST
INTO THE CAROLINAS ON THURS. AT THE SAME TIME AN IMPULSE WILL RIDE
UP AROUND THE ATLANTIC RIDGE FROM THE BAHAMAS AND MAY ADD TO THE
OVERALL MOISTURE REACHING INTO THE CAROLINAS ON THURS. EXPECT
CONVECTION DEVELOPMENT ALONG AN AHEAD OF THIS COLD FRONT AS IT
MOVES EASTWARD REACHING THE COAST THURS NIGHT INTO FRI MORNING.
WILL CONTINUE WITH MAIN FOCUS OF CONVECTION ON THURS INTO THURS
NIGHT.
ONCE THE FRONT MOVES THROUGH BY FRIDAY DRIER AND COOLER AIR WILL
MOVE IN WITH 850 TEMPS DROPPING FROM AROUND 15 C WED AFTN DOWN TO
ABOUT 5 C BY SAT MORNING. H5 HEIGHTS WILL DROP AROUND 20 DEM BY
SAT MORNING. OVERALL EXPECT COOLER WEATHER HEADING INTO NEXT
WEEKEND. TEMPS WILL RUN SEVERAL DEGREES ABOVE NORMAL TO START
REACHING WELL INTO THE 80S ON WED. THE DEWPOINT TEMPS WILL BE IN
THE MID 60S AHEAD OF THE FRONT BUT WILL DROP INTO THE 40S BY THE
WEEKEND WITH TEMPS SEVERAL DEGREES BELOW NORMAL. EXPECT HIGH TEMPS
ONLY IN THE LOWER TO MID 70S FOR THE WEEKEND.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
AS OF 06Z...RADAR IMAGERY SHOWS SOME SHOWERS OVER SOUTH CAROLINA
ASSOCIATED WITH AN UPPER DISTURBANCE. THE LATEST HRRR RUNS DISSIPATE
MUCH OF THIS ACTIVITY BEFORE IT REACHES NC. PERIODS OF MVFR/IFR
CIGS/VSBYS IN THE EARLY MORNING HOURS...AS THIS MOIST LOW LEVEL
ENVIRONMENT HAS PROVEN TO BE CONDUCIVE FOR FOG/STRATUS. GUIDANCE
FAVORS IFR STRATUS AND REDUCED VSBYS AT KFLO/KLBT. TEMPO IFR
CIGS/VSBYS CANNOT BE RULED OUT ALONG THE COAST AS WELL. ISOLATED
CONVECTION IS POSSIBLE LATER TODAY WITH SURFACE HEATING AS THE LOW
LEVELS MOISTEN. THE SEA BREEZE WOULD LIKELY BE THE FOCUS FOR ANY
SHOWER ACTIVITY...WITH THE BEST CHANCES AT THE INLAND TERMINALS
LATER THIS AFTERNOON. WILL MAINTAIN VCSH ATTM SINCE COVERAGE WILL
BE SPOTTY AT BEST. SOUTHWEST WINDS 5-10 KTS WILL BECOME SOUTH
AROUND 10 KTS IN THE AFTERNOON AS THE SEA BREEZE PUSHES INLAND.
EXTENDED OUTLOOK...EARLY MORNING IFR FG/STRATUS IS POSSIBLE THROUGH
THE EXTENDED PERIOD...MAINLY INLAND TERMINALS. OTHERWISE VFR.
CHANCE OF SHOWERS/TSTMS MONDAY...MAINLY LATE WEDNESDAY INTO THURSDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 4 AM SUNDAY...MANAGEABLE MARINE CONDITIONS EXPECTED TODAY AS
A WEAK COLD FRONT N AND W OF THE WATERS DISSIPATES. THIS WILL
LEAVE A LIGHT SW WIND FLOW ACROSS THE WATERS THROUGH TONIGHT. SEAS
GENERALLY 2-3 FEET...IN A MIX OF SSW WAVES 1-2 FEET EVERY 4-5 SEC
AND SE WAVES 1-2 FT EVERY 7-8 SECONDS. ISOLATED TSTMS ARE POSSIBLE
NEAR SHORE THIS AFTERNOON INTO THIS EVENING...AND THE MOTION WILL BE
FROM SW TO NE.
SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
AS OF 330 AM SUNDAY...SOUTHERLY FLOW AROUND BERMUDA HIGH WILL
CONTINUE THROUGH EARLY NEXT WEEK. EXPECT S-SW WINDS 10-15 KTS
THROUGH THE PERIOD...WITH LITTLE FLUCTUATION IN STRENGTH OR
DIRECTION EITHER DAY. THESE WINDS PLUS THE PERSISTENT FETCH AROUND
THE OFFSHORE HIGH PRESSURE WILL CREATE 2-3 FT SEAS EACH DAY...WITH
A WAVE SPECTRUM COMPRISED OF A SOUTHERLY 4-5 SEC WIND WAVE AND A
LOW-AMPLITUDE SE GROUND SWELL.
LONG TERM /WEDNESDAY THROUGH THURSDAY/...
AS OF 330 AM SUNDAY...HIGH PRESSURE BECOMES MORE ORIENTED NORTH TO
SOUTH FROM THE WATERS OFF OF NEW ENGLAND COAST DOWN TO THE LOCAL
WATERS OFF THE SOUTHEAST COAST THROUGH MID WEEK. THE FLOW AROUND
THE HIGH WILL REMAIN ORIENTED NORTH TO SOUTH WITH WINDS S-SE TO
START AROUND 10 TO 15 KTS. BY THURSDAY...GRADIENT TIGHTENS AS
DIGGING MID TO UPPER TROUGH PUSHES A COLD FRONT EAST INTO THE
CAROLINAS. THIS WILL PRODUCE AN INCREASE IN WINDS UP AROUND 15
KTS. IN TURN...YOU CAN EXPECT AN INCREASE IN SEAS UP FROM AROUND 2
TO 3 FT EARLY WED TO 3 TO 4 FT BY THURS NIGHT. BEST SHOT OF
SHOWERS AND THUNDERSTORMS WILL COME LATE THURS ASSOCIATED WITH
COLD FRONT.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...MJC
SHORT TERM...RGZ
LONG TERM...RGZ
AVIATION...MJC/BJR
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1036 AM CDT SUN MAY 11 2014
.UPDATE...
ISSUED AT 1035 AM CDT SUN MAY 11 2014
WEAK UPPER LEVEL IMPULSE IS RESPONSIBLE FOR AN AREA OF SHOWERS
FROM MINOT AND MOHALL NORTHEAST THROUGH WESTHOPE AND BOTTINEAU.
THE AREA HAS MOVED LITTLE THE PAST FEW HOURS...BUT CONTINUES TO
SHRINK IN AREAL COVERAGE. WILL KEEP HIGH POPS IN THIS AREA THROUGH
THE MORNING WITH DECREASING POPS BY EARLY AFTERNOON. ANOTHER AREA
OF SHOWERS ASSOCIATED WITH A CENTRAL PLAINS STORM SYSTEM CONTINUES
TO LIFT NORTH TOWARD SOUTHERN NORTH DAKOTA. HOWEVER...PROGRESS HAS
SLOWED AND WILL REMOVE MENTION OF PRECIPITATION THIS MORNING OVER
THE FAR SOUTH CENTRAL INTO THE JAMES RIVER BASIN...WITH INCREASING
POPS DURING THE AFTERNOON.
RAISED SKY COVER MOST AREAS THIS MORNING...KEEPING OVERCAST SKIES
CENTRAL AND SOUTHWEST THROUGH THE DAY. ALSO RAISED WINDS TODAY
CENTRAL AND SOUTHWEST. LATEST 13 UTC RAP INDICATES 25-30 KNOT
WINDS POTENTIALLY WORKING DOWN TO THE SURFACE THIS AFTERNOON. THIS
WOULD BE NEAR ADVISORY CRITERIA. WILL MONITOR WINDS BUT HOLD OFF
ON ANY ADVISORY FOR NOW.
UPDATE ISSUED AT 654 AM CDT SUN MAY 11 2014
UPDATED THE FORECAST TO INCREASE MORNING POPS OVER NORTH CENTRAL
NORTH DAKOTA WHERE THE LATEST RADAR/SURFACE OBS INDICATED ONGOING
RAIN SHOWER ACTIVITY. ALSO DECREASED POPS SOUTHWEST BASED ON
LATEST RADAR TRENDS. THE LATEST HRRR PROGS RAIN SHOWER ACTIVITY
OVER NORTHERN NORTH DAKOTA TO DIMINISH THIS AFTERNOON WITH RAIN
SHOWERS DEVELOPING OVER THE SOUTHERN JAMES RIVER BASIN THIS
AFTERNOON. GENERALLY FOLLOWED THE HRRR PROG WITH RESPECT TO POP
TRENDS TODAY. OTHERWISE...THE REMAINING WEATHER ELEMENTS ARE IN
GOOD SHAPE. THE UPDATED PRODUCTS HAVE BEEN SENT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 350 AM CDT SUN MAY 11 2014
THE FOCUS IN THE SHORT TERM IS ON THE PROGRESSION OF PRECIPITATION
THROUGH TONIGHT.
LATEST REFLECTIVITY SHOWS THE MAJORITY OF PRECIPITATION OVER NORTH
CENTRAL NORTH DAKOTA. THE 00 UTC WRF AND LATEST HRRR RUNS HAVE
VERIFIED PRETTY WELL WITH CURRENT OBSERVATIONS. ON THE OTHER HAND
THE 00 UTC RUNS OF THE GFS...NAM...ECMWF...AND NHEM GEM HAD A
DIFFICULT TIME NAILING DOWN THE PRECIPITATION OVER THE NORTH CENTRAL
AND ALL OVERPLAYED THE WRAP AROUND PRECIPITATION LOCATED OVER
EASTERN MONTANA AND WESTERN NORTH DAKOTA. WITH THAT SAID USED THE
HRRR AND 00 UTC WRF RUN FOR POPS THROUGH 12 UTC SUNDAY THEN A MODEL
BLEND FROM 12 UTC SUNDAY THROUGH 12 UTC MONDAY SINCE MODEL AGREEMENT
WAS GOOD ON THE WEST TO EAST PROGRESSION OF PRECIPITATION THROUGH SUNDAY.
AT THIS TIME NO THUNDERSTORM ACTIVITY IS EXPECTED SUNDAY...JUST A
CHILLY RAW DAY. WINDS WILL ALSO BE BREEZY 15 TO 25 MPH FROM THE
NORTHWEST SUSTAINED ACROSS THE WEST AND CENTRAL. NO WIND ADVISORY IS
ANTICIPATED AT THIS TIME.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 350 AM CDT SUN MAY 11 2014
THE 00Z GFS/GEM/ECMWF PROG AN OPEN WAVE TO MEANDER OVER
SOUTHEASTERN SASKATCHEWAN/WESTERN NORTH DAKOTA MONDAY. THIS WILL
LEAD TO ENHANCED PRECIPITATION CHANCES EAST OF HIGHWAY 83...MAINLY
OVER THE JAMES RIVER BASIN. THE OPEN WAVE IS THEN PROGGED TO
SLOWLY MEANDER EAST...SHIFTING PRECIPITATION CHANCES EAST ALONG
WITH IT. SOME WRAP AROUND MOISTURE WILL GENERATE A SLIGHT CHANCE
OF SHOWERS OVER WESTERN AND CENTRAL NORTH DAKOTA LATE TUESDAY.
HOWEVER...RAINFALL AMOUNTS SHOULD BE VERY LIGHT IF ANY RAIN WERE
TO DEVELOP.
BY WEDNESDAY AND THURSDAY...SYNOPTIC SUBSIDENCE IS PROGGED TO
OVERSPREAD THE STATE AHEAD OF A DEVELOPING PACIFIC RIDGE. THIS
SHOULD LEAD TO MAINLY DRY CONDITIONS WITH HIGHS IN THE UPPER 50S.
THE MEDIUM RANGE MODELS NOW PROG A WEAK WAVE TO TRAVERSE NORTH
DAKOTA FRIDAY/FRIDAY NIGHT. INDICATED SLIGHT CHANCE POPS AS A
RESULT. THE PACIFIC RIDGE IS THEN FORECAST TO TRANSLATE EAST INTO
THE GREAT PLAINS BY SATURDAY. IF THIS VERIFIES...IT SHOULD GENERATE
DRY CONDITIONS AND HIGHS IN THE MID 60S BY THE END OF THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1035 AM CDT SUN MAY 11 2014
WIDESPREAD CLOUD COVER ACROSS MOST OF THE AREA TODAY. MVFR TO
OCCASIONAL IFR CEILINGS AT KDIK THROUGH KMOT...WITH MVFR CEILINGS
AT KBIS AND KJMS. EXPECT CEILINGS TO SLOWLY LIFT THROUGH THE DAY
WITH PERHAPS SOME LOW VFR CEILINGS BY LATE AFTERNOON. AT KISN
WHICH IS ON THE BACK EDGE OF CLOUD COVER IS EXPECTED TO REMAIN
MAINLY VFR TODAY...WITH A POSSIBLE HIGH MVFR CEILING AS CUMULUS
DEVELOPS AND LIFTS LATE THIS MORNING INTO EARLY AFTERNOON. TONIGHT
EXPECT MVFR TO LOW VFR CEILINGS TO CONTINUE WITH THE EXCEPTION OF
KISN WILL REMAIN VFR. SHOWERS WILL LIFT NORTH AND AFFECT KBIS AND
KJMS LATE THIS AFTERNOON THROUGH THIS EVENING. MODERATE TO STRONG
NORTH FLOW WILL CONTINUE THROUGH THE ENTIRE TAF PERIOD.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...MM
LONG TERM...TM
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
654 AM CDT SUN MAY 11 2014
.UPDATE...
ISSUED AT 654 AM CDT SUN MAY 11 2014
UPDATED THE FORECAST TO INCREASE MORNING POPS OVER NORTH CENTRAL
NORTH DAKOTA WHERE THE LATEST RADAR/SURFACE OBS INDICATED ONGOING
RAIN SHOWER ACTIVITY. ALSO DECREASED POPS SOUTHWEST BASED ON
LATEST RADAR TRENDS. THE LATEST HRRR PROGS RAIN SHOWER ACTIVITY
OVER NORTHERN NORTH DAKOTA TO DIMINISH THIS AFTERNOON WITH RAIN
SHOWERS DEVELOPING OVER THE SOUTHERN JAMES RIVER BASIN THIS
AFTERNOON. GENERALLY FOLLOWED THE HRRR PROG WITH RESPECT TO POP
TRENDS TODAY. OTHERWISE...THE REMAINING WEATHER ELEMENTS ARE IN
GOOD SHAPE. THE UPDATED PRODUCTS HAVE BEEN SENT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 350 AM CDT SUN MAY 11 2014
THE FOCUS IN THE SHORT TERM IS ON THE PROGRESSION OF PRECIPITATION
THROUGH TONIGHT.
LATEST REFLECTIVITY SHOWS THE MAJORITY OF PRECIPITATION OVER NORTH
CENTRAL NORTH DAKOTA. THE 00 UTC WRF AND LATEST HRRR RUNS HAVE
VERIFIED PRETTY WELL WITH CURRENT OBSERVATIONS. ON THE OTHER HAND
THE 00 UTC RUNS OF THE GFS...NAM...ECMWF...AND NHEM GEM HAD A
DIFFICULT TIME NAILING DOWN THE PRECIPITATION OVER THE NORTH CENTRAL
AND ALL OVERPLAYED THE WRAP AROUND PRECIPITATION LOCATED OVER
EASTERN MONTANA AND WESTERN NORTH DAKOTA. WITH THAT SAID USED THE
HRRR AND 00 UTC WRF RUN FOR POPS THROUGH 12 UTC SUNDAY THEN A MODEL
BLEND FROM 12 UTC SUNDAY THROUGH 12 UTC MONDAY SINCE MODEL AGREEMENT
WAS GOOD ON THE WEST TO EAST PROGRESSION OF PRECIPITATION THROUGH SUNDAY.
AT THIS TIME NO THUNDERSTORM ACTIVITY IS EXPECTED SUNDAY...JUST A
CHILLY RAW DAY. WINDS WILL ALSO BE BREEZY 15 TO 25 MPH FROM THE
NORTHWEST SUSTAINED ACROSS THE WEST AND CENTRAL. NO WIND ADVISORY IS
ANTICIPATED AT THIS TIME.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 350 AM CDT SUN MAY 11 2014
THE 00Z GFS/GEM/ECMWF PROG AN OPEN WAVE TO MEANDER OVER
SOUTHEASTERN SASKATCHEWAN/WESTERN NORTH DAKOTA MONDAY. THIS WILL
LEAD TO ENHANCED PRECIPITATION CHANCES EAST OF HIGHWAY 83...MAINLY
OVER THE JAMES RIVER BASIN. THE OPEN WAVE IS THEN PROGGED TO
SLOWLY MEANDER EAST...SHIFTING PRECIPITATION CHANCES EAST ALONG
WITH IT. SOME WRAP AROUND MOISTURE WILL GENERATE A SLIGHT CHANCE
OF SHOWERS OVER WESTERN AND CENTRAL NORTH DAKOTA LATE TUESDAY.
HOWEVER...RAINFALL AMOUNTS SHOULD BE VERY LIGHT IF ANY RAIN WERE
TO DEVELOP.
BY WEDNESDAY AND THURSDAY...SYNOPTIC SUBSIDENCE IS PROGGED TO
OVERSPREAD THE STATE AHEAD OF A DEVELOPING PACIFIC RIDGE. THIS
SHOULD LEAD TO MAINLY DRY CONDITIONS WITH HIGHS IN THE UPPER 50S.
THE MEDIUM RANGE MODELS NOW PROG A WEAK WAVE TO TRAVERSE NORTH
DAKOTA FRIDAY/FRIDAY NIGHT. INDICATED SLIGHT CHANCE POPS AS A
RESULT. THE PACIFIC RIDGE IS THEN FORECAST TO TRANSLATE EAST INTO
THE GREAT PLAINS BY SATURDAY. IF THIS VERIFIES...IT SHOULD GENERATE
DRY CONDITIONS AND HIGHS IN THE MID 60S BY THE END OF THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 654 AM CDT SUN MAY 11 2014
SURFACE LOW IS LOCATED IN SOUTHEAST NORTH DAKOTA AND MOVING EAST.
SCATTERED SHOWERS AND LOW CEILINGS ACROSS NORTH DAKOTA WILL CAUSE
IFR TO LOW VFR CONDITIONS THROUGH THE 12 UTC TAF CYCLE. BREEZY
NORTHWEST WINDS SUSTAINED FROM 15 TO 25 MPH AND GUSTING OVER 30
MPH ARE ANTICIPATED THROUGH THE 12 UTC TAF CYCLE FOR ALL OF THE
CENTRAL AND WESTERN NORTH DAKOTA TERMINALS. CONDITIONS WILL
IMPROVE FROM WEST TO EAST TONIGHT INTO TOMORROW MORNING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TM
SHORT TERM...MM
LONG TERM...TM
AVIATION...MM
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
629 AM CDT SUN MAY 11 2014
.DISCUSSION...
SEE THE 12Z AVIATION DISCUSSION BELOW.
40
&&
.AVIATION...
ALTHOUGH THERE WERE A FEW BREAKS...MVFR TO IFR CEILINGS WERE OVER
THE TERMINAL SITES AT 11Z. THE NAM12 MODEL SHOWED A GOOD POTENTIAL
FOR BREAKS TO BECOME MORE PREVALENT MAINLY THROUGH 16Z.
OTHERWISE...THE MVFR DECK SHOULD GRADUALLY BECOME VFR FROM KHOU
AND KSGR INLAND TO KCLL AND KUTS. AS THE CEILINGS RISE...BREEZY
SURFACE WINDS ARE EXPECTED. LOW CEILINGS OVER THE GULF PLATFORMS
CONCUR WITH THE MODELS IN KEEPING MVFR CONDITIONS OVER KGLS AND
KLBX THROUGHOUT THE DAY.
DO NOT SEE MUCH CHANGE IN THE AIRMASS TONIGHT. WARM AIR AND MOIST
ADVECTION WILL PERSIST. CONDITIONS WILL WORSEN THIS EVENING AND
WILL LIKELY BECOME MVFR AND PROBABLY IFR AROUND 00Z AT KGLS AND
KLBX...AND BETWEEN 03Z AND 06Z OVER THE REMAINING INLAND SITES.
40
&&
.PREV DISCUSSION... /ISSUED 404 AM CDT SUN MAY 11 2014/
DISCUSSION...
AT 3 AM...TEMPERATURES WERE STILL IN THE MID 70S. SOME PATCHY
DRIZZLE MOVED THROUGH EARLIER IN THE NIGHT AND WOULD NOT BE
SURPRISED IF MORE LIGHT RAIN DEVELOPS THIS MORNING. THE RAP 13
SHOWS A CLUSTER OF SHRA/TSRA DEVELOPING OVER PARTS OF EASTERN
HARRIS...GALVESTON...LIBERTY AND CHAMBERS COUNTIES THIS AFTN. THE
HRR IS LESS AGGRESSIVE BUT IT SHOWS SOMETHING SIMILAR. PW VALUES
ARE PROGGED TO BE AROUND 1.4-1.5 INCHES AND UPPER LEVEL WINDS WILL
REMAIN BROADLY DIVERGENT. CAN`T RULE OUT A STRAY SHOWER ACROSS THE
CWA...SO WILL MAINTAIN THE 20 POPS ALREADY IN PLACE.
PWATS INCREASE TO AROUND 1.7 INCHES ON MONDAY AFTN. CAPE VALUES
ARE ABOVE 2000 AND LI`S ARE -8. A CAPPING INVERSION IS STILL IN
PLACE DURING THE MORNING BUT RAPIDLY ERODES IN THE AFTN. A WEAK
UPPER LEVEL DISTURBANCE WILL APPROACH SE TX IN THE AFTN AND THIS
FEATURE COUPLED WITH STRONGLY DIVERGENT UPPER LEVEL WINDS AND
DAYTIME HEATING SHOULD ALLOW SHRA/TSRA TO DEVELOP IN THE AFTN.
ALTHO CURRENTLY NOT OUTLOOKED BY SPC...THERE ARE ENOUGH PARAMETERS
IN PLACE TO GET AT LEAST SOME PULSE SEVERE STORMS ON MON AFTN.
THE UPPER TROUGH INCHES EVER CLOSER MON NITE AND TUESDAY. THE
UPPER JET IS IN A FAVORABLE POSITION AND SE TX WILL LIE IN A RRQ
OF A SPLITTING JET. PWATS INCREASE TO 1.7-1.9 INCHES AND CAPPING
IS NO LONGER AN ISSUE. A SURFACE COLD FRONT WILL SLOWLY CROSS SE
TX ON TUESDAY AND WILL SERVE AS THE LOW LEVEL FOCUS FOR SHRA/TSRA.
POST FRONTAL RAINS ARE ALSO EXPECTED AS THE UPPER TROUGH LAGS
BEHIND A BIT. CONVERGENCE IS ALSO LOOKING PRETTY STOUT AT 850 MB.
LOCALLY HEAVY RAIN WILL BE POSSIBLE ON TUESDAY OVER PARTS OF SE
TX DUE TO THE HIGH MOISTURE CONTENT...FAVORABLE UPPER LEVEL WINDS
AND THE POTENTIAL FOR TRAINING OF STORMS. WPC HAS A RATHER
GENEROUS QPF BULLSEYE OVER SE TX. LIGHT RAIN WILL LINGER TUESDAY
NIGHT AND WILL END WEDNESDAY MORNING ONCE THE UPPER TROUGH PUSHES
EAST OF THE REGION. FWIW...THE NAM 12 IS CONSIDERABLY WEAKER WITH
THE UPPER TROUGH AND DRIER WITH VERY LITTLE RAIN OVER SE TX. THE
NAM IS CURRENTLY THE OUTLIER BUT IT HAS PERFORMED RELATIVELY WELL
AS OF LATE.
SKIES SHOULD CLEAR ON WEDNESDAY AFTN WITH GENERALLY CLEAR SKIES
THROUGH NEXT WEEKEND. TEMPERATURES WILL BE UNSEASONABLY COOL IN
THE WAKE OF TUESDAYS COLD FRONT. MIN TEMPS WILL FALL INTO THE 50S
WED-FRI WITH MAYBE SOME 40S ON THURSDAY MORNING. TEMPS WILL WARM
TO SEASONAL NORMALS BY NEXT WEEKEND. 43
MARINE...
IN ADDITION TO MODERATE TO STRONG ONSHORE WINDS...AREAS OF DRIZZLE
AND LIGHT RAIN WILL AFFECT THE MARINE AREAS THIS MORNING. WENT WITH
HIGHER WIND SPEEDS THAN FORECAST BY THE MODELS GIVEN THE GOOD
THERMAL GRADIENT IN PLACE. THE PRESSURE GRADIENT IS ALSO FORECAST BY
THE MODELS TO BE INCREASING LATER THIS MORNING.
LIKED A COMBINATION OF THE NAM12 AND MOS GUIDANCE TONIGHT THROUGH
MONDAY NIGHT. STAYED WITH THE GFS OUTPUT FOR THE FRONTAL PASSAGE OFF
THE COAST TUESDAY EVENING. STRONG OFFSHORE WINDS WILL THEN QUICKLY
BECOME NORTHEAST AND DIMINISH LATE WEDNESDAY AND THURSDAY MORNING.
40
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 89 73 87 65 74 / 20 10 50 60 60
HOUSTON (IAH) 88 74 86 72 82 / 20 10 40 50 60
GALVESTON (GLS) 83 74 82 74 81 / 20 10 30 40 60
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION UNTIL 1 PM CDT THIS
AFTERNOON FOR THE FOLLOWING ZONES: GALVESTON BAY...
MATAGORDA BAY...WATERS FROM FREEPORT TO THE MATAGORDA SHIP
CHANNEL 20 NM TO 60 NM...WATERS FROM FREEPORT TO THE
MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS FROM HIGH ISLAND
TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH ISLAND TO
FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...47
AVIATION/MARINE...40
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
1043 AM CDT SUN MAY 11 2014
.AVIATION/18Z TAFS/...CIRRUS CONTINUES TO ADVANCE ACROSS SRN WI
BLOWING OFF THE TOPS OF IOWA COMPLEX. THIS PRECIP WILL BE
OUTRUNNING THE LLJ AXIS WITH TIME TODAY. HRRR AND 4KM SPC WRF SHOW
SOME OF THE REMNANTS OF THIS AFFECTING SRN WI LATER TODAY.
STRONGEST STORMS PROGGD TO REMAIN SOUTH BUT WILL KEEP A CLOSE EYE
ON OUR SRN CNTYS AS THE SRN IA STORMS ADVANCE CLOSER. MORE
DEVELOPMENT LIKELY TONIGHT AS LLJ REFOCUSES TO OUR WEST AND THE
LOW TO OUR WEST STRENGTHENS. PROGS ARE KEYING ON IA/SE
MN/CNTRL/NRN WI THOUGH 00Z ECMWF SHOWED A MORE ORGANIZED WAA WING
DVLPG ACRS SRN WI TNT. WILL BE INTERESTING TO SEE HOW THE 12Z RUN
TRENDS. POTENTIAL FOR MORE SHRA/TSRA ON MONDAY WITH
WARM/HUMID/UNSTABLE AIRMASS THOUGH COLD FRONT STILL BACK TO OUR
WEST AND NOT EXPECTED TO ARRIVE UNTIL MONDAY NIGHT.
PC
&&
.PREV DISCUSSION... /ISSUED 332 AM CDT SUN MAY 11 2014/
TODAY AND TONIGHT...FORECAST CONFIDENCE...HIGH
UPPER LEVEL RIDGING OCCURS TODAY AND INTO TONIGHT AHEAD OF THE
STRONG WESTERN TROUGH MOVING ACROSS THE ROCKIES. ONE JET MAX OVER
THE UPPER GREAT LAKES MOVES OFF TO THE EAST TODAY AS THE STRONGER
JET ASSOCIATED WITH THE WESTERN TROUGH BEGINS TO ROUND THE BASE OF
THE TROUGH THIS MORNING...AND MOVES NORTHEAST OVER THE EASTERN
SECTION OF THE TROUGH TONIGHT. UPPER DIVERGENCE INCREASES THIS
AFTERNOON OVER SOUTHERN WISCONSIN WITH THE DIVERGENCE INCREASING TO
RATHER STRONG VALUES TONIGHT. 850/700 MB DEW POINTS INCREASE TODAY
WITH 850 MB DEWPOINTS RISING TO 14 CELSIUS THIS EVENING UNTIL THE
CONVECTION OCCURS.
700 MB WINDS INCREASE THIS AFTERNOON AND AGAIN LATE TONIGHT REACHING
40 KNOTS. AT 850 MB WINDS INCREASE LATER THIS EVENING AS A 55 KNOT
LOW LEVEL JET APPROACHES FROM MISSOURI. SOUTHERN WISCONSIN REMAINS
IN THE NOSE OF THE JET THROUGH THE EARLY MORNING MONDAY. AS A
RESULT 850 MB MOISTURE CONVERGENCE INCREASES.
THIS SHOULD SET THE STAGE FOR AN MCS NORTH OF THE ADVANCING WARM
FRONT. EXPECT THUNDERSTORMS TONIGHT...SOME WITH HEAVY RAINFALL...
ALONG WITH A LARGE HAIL POTENTIAL GIVEN THE 1500 JOULES/KG OF
ELEVATED CAPE WITH THE EQUILIBRIUM LEVEL UP TO 36 THSD FT. WET BULB
ZERO IS AROUND 10 THSD FT...BUT LOW LEVELS SHOULD BE RATHER COOL
NORTH OF THE WARM FRONT. LOCAL SEVERE PROBABILITY CWASP VALUES
INCREASE TO 80 PCT INTO PORTIONS OF SOUTH CENTRAL WISCONSIN
BY EARLY MONDAY MORNING ON THE NAM AND GFS.
THERE WILL BE A CHANCE FOR THUNDERSTORMS EVEN THIS AFTERNOON WITH
CAPE VALUES AROUND 1000 JOULES/KG AS THE 850/700 MB MOISTURE
INCREASES.
MONDAY AND TUESDAY...FORECAST CONFIDENCE...MEDIUM
SHOWERS AND THUNDERSTORMS WILL BE LIKELY AGAIN MONDAY AND MONDAY
NIGHT...LINGERING ALSO INTO TUESDAY. THE BIGGEST ISSUE MON/TUE IS
THE LOW TRACK AND TIMING...WHICH WILL PLAY A BIG ROLE IN STORM
TIMING AND SEVERE POTENTIAL. UNFORTUNATELY...MODELS HAVE DIVERGED
A BIT MORE WITH THE TRACK OF THE SFC LOW IN THE LATEST RUNS. BY
TUESDAY MORNING...THE CENTER OF THE SFC LOW IS RIGHT OVER THE
FORECAST AREA VIA THE ECMWF...NEAR MINNEAPOLIS VIA THE NAM...AND
JUST NORTH OF MINNESOTA VIA THE CANADIAN AND GFS SOLUTIONS. TOOK A
BLEND OF THE LOW TRACKS FOR NOW...BRINGING THE COLD FRONT THROUGH
BY TUESDAY MORNING. THE QUICKER SOLUTIONS WOULD LIKE POSE A
GREATER SEVERE WEATHER THREAT MONDAY...WITH THE COLD FRONT CLOSER
TO THE FORECAST AREA BY THE END OF PEAK HEATING. SPC HAS
MAINTAINED A SLIGHT RISK OF SEVERE STORMS FOR THE ENTIRE FORECAST
AREA.
TEMPERATURES MONDAY AND TUESDAY WILL ALSO BE DEPENDENT ON THE
TIMING OF THE LOW...AS A SLOWER SOLUTION WILL LIKELY ALLOW MORE A
CHANCE FOR A LITTLE FILTERED SUNSHINE MONDAY. WITH 925 MB TEMPS
PEAKING IN THE 19-22C RANGE...IT WOULD NOT TAKE MUCH HEATING FOR
TEMPS TO SHOOT UP AROUND 80...ESPECIALLY IN THE SOUTHEAST. DECIDED
TO BUMP TEMPS UP A TAD FROM THE PREVIOUS FORECAST. A SLOWER
SOLUTION WOULD ALSO RESULT IN SOMEWHAT MILDER TEMPS AT LEAST
THROUGH TUESDAY MORNING...SO ALSO BUMPED TUESDAY HIGHS UP A
LITTLE.
WEDNESDAY THROUGH SATURDAY...FORECAST CONFIDENCE...MEDIUM
A RETURN TO THE BELOVED NORTHWEST FLOW PATTERN WILL LIKELY RESULT
IN BELOW NORMAL TEMPERATURES FOR WEDNESDAY THROUGH THE END OF THE
WEEK. ADDITIONALLY...A SERIES OF SHORTWAVES WITHIN THE FLOW WILL
BRING A GOOD AMOUNT OF CLOUDS ALONG WITH A CHANCE FOR SHOWERS MOST
DAYS. SO...ENJOY THE MILDER TEMPERATURES WHILE THEY ARE STILL
HERE.
AVIATION/12Z TAFS/...
MAINLY VFR CONDITIONS TODAY WITH MID LEVEL CLOUDS INCREASING WITH
ADVANCING MOISTURE AHEAD OF A WEAK TROUGH OVER THE UPPER
MISSISSIPPI VALLEY...AND NORTH OF AN ADVANCING WARM FRONT AHEAD OF
STRONG LOW PRESSURE MOVING OUT OF THE TEXAS PAN HANDLE REGION.
SOME CUMULUS EXPECTED THIS AFTERNOON ALONG WITH A CHANCE OF
THUNDERSTORMS..
THE WARM FRONT WILL REACH SOUTHERN WISCONSIN TONIGHT...INCREASING
THE THUNDERSTORMS. SOME MAY PRODUCE HAIL. LOOK FOR MVFR AND IFR
CONDITIONS TO DEVELOP NEAR THE WARM FRONT LATER THIS EVENING AND
LATE TONIGHT.
MARINE...
LIGHT SOUTHEAST WINDS TODAY AHEAD OF AN ADVANCING WARM FRONT. THE
WARM FRONT WILL MOVE NORTH LATER TONIGHT AND REACH NORTHEAST
WISCONSIN LATER MONDAY. LOOK FOR A CHANCE OF THUNDERSTORMS THIS
AFTERNOON WITH PERIODS OF THUNDERSTORMS TONIGHT.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...HENTZ
MONDAY THROUGH SATURDAY...DDV
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
624 AM CDT SUN MAY 11 2014
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 245 AM CDT SUN MAY 11 2014
AXIS OF THE WEST COAST LONG WAVE TROUGH WILL SLIDE OVER THE PLAIN
STATES ON MON...SLOWLY EASING ACROSS THE UPPER MISSISSIPPI RIVER
VALLEY ON WED. BITS OF UPPER LEVEL ENERGY WILL SPIN OUT OF THE
TROUGH...WITH THESE SHORTWAVES TAKING AIM ON THE REGION TODAY AND
MONDAY.
AT THE SFC...A WARM FRONT CURRENTLY WAS RUNNING FROM KS EASTWARD
THROUGH THE MID MISSISSIPPI RIVER VALLEY. THIS IS SLATED TO LIFT
NORTHWARD THROUGH THE DAY TODAY AS A SFC LOW TRACKS INTO IA BY 06Z
TONIGHT. STRONG LOW LEVEL MOISTURE TRANSPORT POINTS INTO AND ACROSS
THE WARM FRONT...DRIVEN BY A 40-50 KT 850 MB JET...AND NOSES INTO
NORTHEAST IA/SOUTHWEST WI BY 06Z. THIS RIBBON OF MOISTURE HOLDS
AHEAD OF A COLD FRONT THROUGH MONDAY...ALTHOUGH NOT NEARLY AS STRONG
AS WHAT IS EXPECTED FOR TONIGHT.
INSTABILITY CLIMBS THROUGH THE DAY...WITH 1000-2000 J/KG OF MUCAPE
STILL EXPECTED FOR MUCH OF THE LOCAL FORECAST AREA BY TONIGHT. IT
STAYS FAIRLY UNSTABLE THROUGH MONDAY...STILL AHEAD OF THE COLD FRONT
WITH THE WARM FRONT EXPECTED TO BE NORTH...SBCAPES AROUND 1500 J/KG.
A LOOK AT THE BUFKIT SOUNDINGS SHOWS THAT MUCH OF THAT CAPE IS OF
THE SKINNY VARIETY TONIGHT...MEANING THAT VIGOROUS UPDRAFTS/RAPID
DEVELOPMENT ARE NOT SUPPORTED BY THE INSTABILITY.
0-6 KM SHEAR RAMPS UP TO 40-50 KTS BY THIS EVENING...BUT A LOT OF
THAT IN THE 0-3 KM LAYER...AROUND 40 KTS OR SO. GOOD TURNING IN THE
LOWEST 1 KM PER BUFKIT HODO...AND 0-1 KM SHEAR RANGES FROM 20-30
KTS DURING THE NIGHT.
SEVERE THREAT HAS CONTINUED TO INCREASE OVER THE PAST COUPLE
DAYS...AND 00Z MODELS ARE NO DIFFERENT. THE STRONG LOW LEVEL
JET/MOISTURE TRANSPORT WILL BE A SIGNIFICANT FACTOR...ALONG WITH THE
POSITIONING OF THE WARM FRONT. WHILE THE INSTABILITY IS NOT OVERLY
FAVORABLE...ADD IN THE VERY GOOD SHEAR AND STORM DEVELOPMENT IS
SUPPORTED. LARGE HAIL AND DAMAGING WINDS ARE THREATS...WINDS
ESPECIALLY IF THERE IS NO NEAR SFC STABLE LAYER. THE LOW LEVEL
CURVATURE/SHEAR ALSO BRINGS A TORNADO THREAT...ESPECIALLY AROUND THE
WARM FRONT WHICH WILL SERVE TO PROVIDE ADDITIONAL...LOCALIZED
VORTICITY. NAM12 SIG TOR PARAMETER AS HIGH AS 2-4 THIS EVENING FOR
NORTHEAST IA/SOUTHWEST WI.
ITS NOT CLEAR-CUT ON HOW HIGH THE RISK FOR SEVERE WILL BE...OR WHERE
IT WILL BE THE GREATEST. POSITIONING OF THE WARM FRONT WILL BE
SIGNIFICANT. GFS/NAM TRENDING TOWARD BRINGING THAT FRONT INTO
CENTRAL IA INTO NORTHERN ILL...ADVANCING NORTH DURING THE
EVENING...NEAR THE I-90 CORRIDOR/SOUTH AROUND 06Z. ITS NOT CERTAIN
IT WILL RUN THIS FAST NORTH AS CONVECTION ALONG AND NORTH OF THE
BOUNDARY SHOULD SERVE TO TEMPER ITS MOVEMENT.
IN ADDITION...THERE WILL BE A THREAT FOR SOME SHOWERS/STORMS THIS
AFTERNOON...WELL BEFORE THE EXPECTED CONVECTION OF TONIGHT. THE LOW
LEVEL JET IS EXPECTED TO SPARK A THUNDERSTORM COMPLEX OVER THE
SOUTHERN PLAINS...WHICH THE HRRR TAKES NORTHEAST TOWARD THE AREA.
HOW LONG THE CONVECTION WILL HOLD TOGETHER AS THE LOW LEVEL
JET/MOISTURE TRANSPORT TEMPORARILY WEAKENS AT MIDDAY IS IN QUESTION.
ITS MCV COULD SERVE AS FORCING MECHANISM LATER IN THE AFTERNOON. IF
THE PCPN DOESN/T REACH THE FORECAST AREA...DEBRIS CLOUDS PROBABLY
WILL...AND COULD TEMPER THE WARMING AND THUS INSTABILITY SOME NORTH
OF THE WARM FRONT.
ALL THIS SAID...SEE A SEVERE THREAT TONIGHT...ESPECIALLY ACROSS
NORTHEAST IA/SOUTHWEST WI. PROBABLY MORE MID/LATE EVENING. HAIL IS
THE TOP THREAT...BUT SIGNIFICANT 0-3 KM SHEAR COULD RESULT IN
DAMAGING WINDS IF THERE IS NOT A STRONG STABLE NEAR SFC LAYER.
BUFKIT SOUNDINGS SUGGEST THERE PROBABLY WON/T BE. AND...A TORNADO
THREAT CANNOT BE RULED OUT. LOW LEVEL CURVATURE AND 0-1 KM SHEAR
SUPPORTS IT...AND THE SIG TOR PARAMETER PEGS IT. ESPECIALLY
CONCERNED ABOUT ANY STORMS RIDING THE WARM FRONT. THERE ARE CAVEATS
TO THE RISK PER WHERE CONVECTION GOES...BOUNDARIES...ETC...BUT ITS A
SITUATION THAT NEEDS TO BE MONITORED VERY CLOSELY. EXPECTING WATCHES
AND WARNINGS TONIGHT.
ALL THAT SAID AND HAVEN/T EVEN TOUCHED ON THE HEAVY RAIN THREAT.
MORE ON THAT IN THE HYDROLOGY SECTION BELOW.
.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 245 AM CDT SUN MAY 11 2014
GFS/ECMWF PROMISE TO KEEP THE REGION UNDER THE INFLUENCE OF AN UPPER
LEVEL TROUGH FOR MUCH OF THE NEW WEEK. BITS OF ENERGY WILL MOVE
THROUGH THE TROUGH AND BRING A SHOWER THREAT FROM TIME TO
TIME...ALTHOUGH WHEN/WHERE THE RAIN CHANCES WILL BE ARE NOT
CERTAIN...WITH MODEL VARIANCES KEEPING CONFIDENCE LOW. WILL STAY
WITH CONSENSUS SOLUTION FOR CHANCES. TEMPERATURES ARE GOING TO TAKE A
TUMBLE DOWNWARD...WITH EC 850 MB TEMP ANOMALIES HOVERING AROUND -1.
HIGHS WILL STRUGGLE TO BREAK 60 DEGREES SOME DAYS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 624 AM CDT SUN MAY 11 2014
ACTIVE WEATHER OVER THE NEXT 24 HOURS WITH THUNDERSTORMS MOVING IN
THIS AFTERNOON...LASTING THROUGH TONIGHT. LOOK FOR VFR CONDITIONS
THROUGH THIS MORNING WITH A FEW -SHRA MOVING OUT OF THE PLAINS
INTO THE AREA IN THE 16-18Z TIMEFRAME. THEN LOOKING FOR SCATTERED
TSRA DEVELOPING THIS AFTERNOON WITH DAYTIME HEATING AND AS A WARM
FRONT PUSHES NORTH TOWARD THE AREA FROM THE PLAINS. LOOK FOR
THUNDERSTORMS TO INCREASE IN COVERAGE AND INTENSITY THIS EVENING
THROUGH THE OVERNIGHT HOURS AS THE WARM FRONT PROGRESSES NORTHWARD
INTO THE REGION. A FEW OF THESE STORMS MAY TURN SEVERE. OTHERWISE...
EXPECTING CONDITIONS TO DETERIORATE INTO MVFR/IFR THIS EVENING
AND OVERNIGHT WITH THE THUNDERSTORM ACTIVITY.
&&
.HYDROLOGY...
ISSUED AT 245 AM CDT SUN MAY 11 2014
SIGNIFICANT LOW LEVEL MOISTURE TRANSPORT KICKS IN TONIGHT...AND
WHILE WEAKENING ON MONDAY...WILL CONTINUE TO FUEL SHOWERS AND
THUNDERSTORMS THROUGH MON NIGHT. PW/S CLIMB TO AROUND 1.5 INCHES.
EXPECT SOME STORMS OVER THE NEXT COUPLE DAYS TO PRODUCE HEAVY RAIN.
MODELS DROP 1-2 INCHES LATE TONIGHT INTO TUE FOR MUCH OF THE
FORECAST AREA. LOCALLY HIGHER AMOUNTS POSSIBLE. THE HEAVIEST RAIN
WILL FALL TONIGHT. DON/T EXPECT A WIDESPREAD FLOOD THREAT AT THE
MOMENT...BUT THERE COULD BE SOME LOCALIZED IMPACTS.
MEANWHILE...MINOR FLOODING/HIGH WATER CONTINUES ALONG PORTIONS OF
THE MISSISSIPPI RIVER. THE ADDITIONAL RAINS COULD HAVE IMPACTS ON
BOTH TRIBUTARIES AND THE MISSISSIPPI RIVER...SLOWING THE RATES OF
FALL...AND/OR PRODUCE ADDITIONAL RISES OR RENEWED FLOODING.
CHECK THE LATEST HYDROLOGIC STATEMENTS FOR THE DETAILS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...RIECK
LONG TERM....RIECK
AVIATION...DAS
HYDROLOGY....RIECK
AREA FORECAST DISCUSSION
NWS PUEBLO CO
338 PM MDT SUN MAY 11 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 258 PM MDT SUN MAY 11 2014
...SIGNIFICANT SNOWS EXPECTED TO CONTINUE ACROSS THE CENTRAL
MOUNTAINS AND PIKES PEAK REGION...
UPPER LOW NEARING THE FOUR CORNERS REGION THIS AFTERNOON WILL BE
LIFTING NORTHEASTWARD OVERNIGHT INTO NORTHEAST CO BY 18Z MONDAY.
SURFACE FRONT HAS PUSHED THROUGH ALL OF THE SOUTHEAST PLAINS AS OF
21Z. SNOWFALL AMOUNTS SO FAR HAVE BEEN HIGHLY DETERMINED BY THE
SNOW LEVELS AND WARM GROUND. PIKES PEAK REGION HAS ALREADY DROPPED
INTO THE LOWER TO MID 30S...WITH UPPER 20S ACROSS TELLER COUNTY.
THIS HAS BEEN THE AREA WHICH HAS RECEIVED THE MOST SNOW...THOUGH A
LOOK AT WEB CAMS ACROSS THE AREA SHOWS THAT WARM GROUND HAS
MITIGATED ACCUMULATIONS SOME. MAINLY GRASSY SURFACES HAVE
ACCUMULATION...BUT OCCASIONALLY HAVE SEEN SOME SNOW ON THE PAVEMENT
DURING THE HEAVIER SNOW BURSTS. STILL WAITING FOR SNOW LEVELS TO
DROP ACROSS THE UPPER ARKANSAS RIVER VALLEY...WITH SALIDA AND BUENA
VISTA AIRPORTS STILL IN THE 40S AS OF 21Z. DOWN AROUND COLORADO
CITY AND RYE...TEMPERATURES ARE STILL IN THE UPPER 30S AND LOWER
40S...BUT TEMPERATURES HAVE BEEN DROPPING QUICKLY THIS LAST HOUR AND
SUSPECT RAIN/SNOW SWITCH OVER FOR THE UPPER ARKANSAS RIVER VALLEY OF
FREMONT AND CHAFFEE AND THE LOWER ELEVATION OF THE WET MOUNTAINS IS
NOT LONG OFF.
AS FOR HIGHLIGHTS...HAVE LEFT THEM AS IS. A LITTLE CONCERNED THAT
LATER SWITCH OVER TO SNOW ACROSS LOWER ELEVATIONS OF CHAFFEE COUNTY
MAY HURT SNOW TOTALS SOME...BUT BEST FORCING WILL CONTINUE TO TREK
ACROSS THIS AREA THROUGH THE EVENING...AND LATEST 18Z NAM IS NOW
HITTING THIS AREA WITH AROUND 4 INCHES OF SNOW THROUGH THE EVENING
HOURS. ONCE THE SWITCH OVER OCCURS...IT WILL NOT TAKE LONG FOR
ACCUMULATIONS TO START STACKING UP...THOUGH SUSPECT THE WARM GROUND
WILL MAKE FOR A WIDE RANGE OF ACCUMULATIONS WITH LOCATIONS LIKE
SALIDA COMING UP ON THE LOW END. ON THE FENCE WITH UPGRADING TO A
WINTER STORM WARNING FOR THE LOWER ELEVATIONS OF THE WET MOUNTAINS
AND THE NORTHERN SANGRE DE CRISTO MOUNTAINS. THERE COULD BE A FEW
AREAS THAT HIT AROUND 12 INCHES...BUT THE LATE TRANSITION OVER TO
SNOW WILL LARGELY KEEP AMOUNTS MORE IN THE ADVISORY RANGE.
AS FOR TIMING OF THE HEAVIER SNOWS...HEAVIEST SHOULD FALL NOW
THROUGH MIDNIGHT. AFTER MIDNIGHT...BEST FORCING SHIFTS NORTH OF THE
AREA...AND ALTHOUGH THERE WILL STILL BE SOME WRAP AROUND SNOWS
ACROSS THE CENTRAL MOUNTAINS/PIKES PEAK AREA...DOWNSLOPE NORTHERLY
WINDS OFF THE PALMER DIVIDE SHOULD OPEN UP THE PRECIPITATION MINIMUM
ACROSS SOUTHERN EL PASO AND NORTHERN PUEBLO COUNTIES. THIS COULD
OCCUR AS EARLY AS 10 PM. WINTER WEATHER ADVISORIES FOR SOUTHERN EL
PASO COUNTY MAY RUN A TAD TOO LONG...BUT WILL LET LATER SHIFTS
MONITOR TRENDS AND MAKE ANY NEEDED ADJUSTMENTS.
THE WET MOUNTAINS AND SOUTHERN I-25 CORRIDOR WILL SEE MORE
CONVECTIVE BURSTS OF RAIN/SNOW...WHICH SHOULD SWITCH OVER TO ALL
SNOW BY AROUND 6 PM. HOWEVER...MAJORITY OF THE HEAVIER SNOW MAY BE
DONE BY 6 AM...AND POSSIBLY EVEN SOONER IF LATEST HRRR IS CORRECT.
AS FOR THE SOUTHEAST PLAINS...HAVE EXTENDED THE FREEZE WARNING TO
INCLUDE CROWLEY COUNTY...AS AM GETTING A FEW HOURS OF SUBFREEZING
TEMPERATURES THERE. NOT MUCH SNOW IS EXPECTED...THOUGH SWITCH OVER
COULD OCCUR AROUND 6 PM FOR PUB...AROUND MIDNIGHT FOR LHX...AND EVEN
LATER FOR POINTS FARTHER EAST WHERE IT MAY STAY ALL RAIN...OR GO TO
A BRIEF RAIN/SNOW MIX TOWARDS MORNING BEFORE IT ENDS. GRASSY
SURFACES AROUND PUEBLO...WALSENBURG...TRINIDAD COULD SEE AN INCH OR
TWO AT ANY TIME...BUT WARM GROUND MAY MELT IT OFF QUICKLY.
ON MONDAY...ANOTHER TRAILING DISTURBANCE DROPS IN IN NORTHWEST FLOW
ALOFT...AND SENDS ANOTHER ROUND OF SNOW INTO THE MOUNTAIN
AREAS...PARTICULARLY ALONG THE CONTINENTAL DIVIDE. THIS CONTINUES
INTO MONDAY EVENING. ITS POSSIBLE THESE AREAS MAY NEED ANOTHER
HIGHLIGHT...MOST LIKELY AN ADVISORY...BUT SINCE THERE SEEMS TO BE A
DISTINCT BREAK BETWEEN THE TWO SYSTEMS...WILL LET LATER SHIFTS
DETERMINE WHAT IF ANY HIGHLIGHTS WILL BE NEEDED. SUSPECT THAT TO
SOME EXTENT...THE HIGHER SNOWFALL AMOUNTS IN THE GFS MAY BE A TAD
OVERDONE DUE TO SOME CONVECTIVE COMPONENT...AND HAVE GONE CLOSER TO
THE NAM FOR NOW. -KT
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 258 PM MDT SUN MAY 11 2014
SECONDARY UPPER LOW AND UPSLOPE FLOW WILL KEEP SOME SNOW GOING
OVER THE SAN JUANS/SANGRES MON EVENING...AND SOME ADDITIONAL LIGHT
ACCUMLATION IS POSSIBLE WITH BEST CHANCE OVER THE EASTERN SAN
JUANS. PRECIP THEN SLOWLY SHIFTS SOUTH OVERNIGHT AS UPPER TROUGH
MOVES EAST...WHICH WILL END MOST ACCUMULATING SNOW BY EARLY
TUESDAY MORNING. MANY AREAS WILL HAVE THE POTENTIAL FOR FREEZING
TEMPS ONCE AGAIN BY EARLY TUE MORNING...THOUGH AMOUNT OF MID LEVEL
CLOUDINESS MAY BE THE DETERMINING FACTOR ON HOW WIDESPREAD COLD
TEMPS BECOME. VERY GRADUAL WARMING AND DRYING TREND BEGINS
TUESDAY AFTERNOON...THOUGH SOME RESIDUAL MOISTURE/INSTABILITY
OVER THE MOUNTAINS MAY PRODUCE A FEW LIGHT SHOWERS TUE AFTERNOON.
NEUTRAL TO WEAK WARM ADVECTION...COMBINED WITH INCREASING MAY SUN
SHOULD BOOST MAX TEMPS SEVERAL DEGF VERSUS MONDAYS HIGHS...THOUGH
READINGS WILL STILL RUN WELL BELOW SEASONAL AVERAGES. ANOTHER THREAT
OF SOME PATCHY FROST TUE NIGHT/WED MORNING AS SKIES
CLEAR...ESPECIALLY EL PASO COUNTY/LOW LYING AREAS OF PUEBLO
COUNTY.
UPPER RIDGE THEN BUILDS OVER THE WESTERN U.S. FOR MID-WEEK...THEN
GRDUALLY FLATTENS NEXT WEEKEND. IN GENERAL...GRADUAL
WARMING/DRYING TREND IN STORE FOR THE AREA THROUGH THE
PERIOD...THOUGH A COUPLE WAVES EMBEDDED IN THE NW FLOW MAY
PRODUCE AT LEAST SOME ISOLATED -TSRA/-SHRA OVER THE EASTERN
MOUNTAINS AND PLAINS THU/FRI AS MODEST LOW LEVEL MOISTURE RETURNS
SLOWLY INTO THE HIGH PLAINS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 258 PM MDT SUN MAY 11 2014
IFR CONDITIONS EXPECTED TO CONTINUE AT KCOS...WITH THE EARLIEST
POTENTIAL FOR RETURN OF MVFR CONDITIONS BETWEEN 04Z AND 06Z.
SNOWFALL WILL MAINLY STAY CONFINED TO THE GRASSY SURFACES WHERE 1
TO 3 INCHES WILL BE POSSIBLE...BUT WARM GROUND MAY CAUSE SOME
MELTING BETWEEN HEAVIER SNOW BURSTS. KPUB WILL REMAIN
-SHRA...UNTIL AROUND 00Z WHEN A -SHRASN MIX CAN BE
EXPECTED...WHICH WILL TRANSITION TO -SHSN BY 03Z. ONLY AN INCH OR
TWO OF SNOWFALL WILL BE POSSIBLE...BUT WARM GROUND WILL LIKELY
MELT THE SNOW AS IT FALLS. KALS WILL SEE MORE SHOWERY NATURE TO
SNOWFALL TONIGHT...WITH OFF AN ON VFR TO MVFR CONDITIONS. ALL 3
TAF SITES WILL SEE GUSTY WINDS THROUGH THE EVENING...WITH KPUB AND
KCOS SEEING GUSTS TO AROUND 40 KTS THROUGH THE EVENING...AND
REMAINING AROUND 15-30 KTS THROUGH THE NIGHT. KALS WILL STAY GUSTY
OUT OF THE SOUTH AT 20- 35KTS THIS EVENING...THEN SWING AROUND TO
THE EAST AROUND 10 KTS THEN DECREASE THROUGH THE LATE EVENING AND
OVERNIGHT.
SHOULD SEE IMPROVING CONDITIONS ON MONDAY WITH VFR CIGS SLOWLY
CLEARING FOR KPUB AND KCOS. KALS MAY SEE SOME VFR CLOUDS REDEVELOP
IN THE AFTERNOON WITH CONVECTIVE RAIN AND SNOW SHOWERS. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING FROM 9 PM THIS EVENING TO 8 AM MDT MONDAY FOR
COZ083>089-094.
WINTER STORM WARNING UNTIL 9 AM MDT MONDAY FOR COZ058>063-073-
076-080>082-084.
WINTER WEATHER ADVISORY UNTIL 9 AM MDT MONDAY FOR COZ072-074-075-
077>079.
WINTER WEATHER ADVISORY UNTIL 6 AM MDT MONDAY FOR COZ066-068-085.
&&
$$
SHORT TERM...KT
LONG TERM...PETERSEN
AVIATION...KT
AREA FORECAST DISCUSSION
NWS POCATELLO ID
150 PM MDT SUN MAY 11 2014
.SHORT TERM...TONIGHT THROUGH WEDNESDAY. AN UPPER LOW CONTINUED TO
SHIFT SE OF THE REGION TODAY AS A RIDGE OF HIGH PRESSURE AMPLIFIED
ALONG THE PAC COAST. A WEAK DISTURBANCE EMBEDDED IN THE NW FLOW
ALOFT WAS NOTED DIGGING SE ALONG THE DIVIDE AND WILL PROVIDE THE
NECESSARY LIFT FOR AFTERNOON CONVECTION ALONG THE MONTANA AND
WYOMING DIVIDE REGIONS TODAY AND MONDAY. OTHERWISE DRY CONDITIONS
WILL OVERSPREAD THE REGION MONDAY/TUESDAY AS THE RIDGE MIGRATES INTO
THE COAST. A WEAK DISTURBANCE TOPPING THE RIDGE WILL DIG SE ALONG
THE DIVIDE WEDNESDAY AFTERNOON PROVIDING A SLIGHT CHANCE OF
AFTERNOON SHOWERS NEAR ISLAND PARK. A STRONG NORTHERLY SURFACE
PRESSURE GRADIENT WAS POSITIONED OVER THE REGION TODAY...PRODUCING
STRONG NORTH WINDS THROUGHOUT THE SNAKE RIVER PLAIN. MODELS INDICATE
THAT AS THE GRADIENT WEAKENS TONIGHT AND MONDAY...THE WINDS WILL
BEGIN TO WEAKEN. STILL...A LAKE WIND ADVISORY REMAINS IN EFFECT FOR
AMERICAN FALLS THIS AFTERNOON/EVE AND HAVE ADDED A WIND ADVISORY
THROUGH EARLY EVENING FOR THE UPPER SNAKE PLAIN DUE TO THE
PERSISTENT STRENGTH OF THE WINDS IN THAT REGION. IT ALSO LOOKS AS IF
THE NORTH WINDS WILL BE STRONG ENOUGH AGAIN MONDAY...ALBEIT MUCH
WEAKER THAN TODAY...TO SUPPORT YET ANOTHER LAKE WIND ADVISORY FOR
AMERICAN FALLS. CLEARING SKIES WILL ONCE AGAIN SUPPORT FREEZING
TEMPERATURES TONIGHT AND MONDAY NIGHT. ALTHOUGH THE MODEST NORTH
WINDS EXPECTED TONIGHT SHOULD MODERATE THE POTENTIAL COOLING...THUS
HAVE CONVERTED THE FREEZE WATCH TO A FROST ADVISORY FOR ZONES 20 AND
21 FOR TONIGHT.
LIGHT WINDS AND CLEAR SKIES TUESDAY MORNING SHOULD BE VERY
SUPPORTIVE OF A HARD FREEZE IN THE UPPER VALLEY AND FROST IN THE
LOWER SNAKE RIVER PLAIN AND ERN MAGIC VALLEY. THUS HAVE ISSUED A
WATCH FOR THAT TIME FRAME. HUSTON
.LONG TERM...WED NIGHT THROUGH NEXT SUN NIGHT. 500MB LONG WAVE
INDICATES A SHIFT FROM A WEAK TROUGH TO ZONAL FLOW OCCURRING EARLY
WITH ZONAL FLOW CONTINUING TO THE END. THIS WILL MEAN A SHORT-WAVE
DOMINATED WEATHER PATTERN AND THUS VERY LITTLE CONSISTENCY WITH
PREVIOUS GUIDANCE RUNS AND POTENTIALLY STRONG DIFFERENCES AMONG
MODEL SOLUTIONS. COMPARED TO YESTERDAY...THE GFS AND ECMWF HAVE
BROUGHT IN MORE MOISTURE AND PRECIPITATION WITH SLIGHTLY COLDER
TEMPERATURES. SO HAVE TRENDED IN THIS DIRECTION. 500MB HEIGHTS ARE
NOT QUITE AS INTENSE AND THE UPPER LEVEL RIDGE IS WEAKER IN
AMPLITUDE. ON SAT NIGHT/SUN...THE GFS IS BRINGING IN A TROUGH...AT
LEAST TO THE NORTHERN END OF THE FORECAST AREA. THE ECMWF PERFORMS
SIMILARLY...SO HAVE BEEFED UP POPS AND CLOUD COVER AND HAVE THE
STRONGEST WINDS DURING THE PERIOD ON THIS DAY. OTHERWISE WINDS ARE
INDICATING GUSTY WINDS OVER THE ARCO DESERT QUITE WELL. MESSICK
&&
.AVIATION...NORTH WIND IN HRRR INDICATES STRONGER WIND LASTING INTO
THE EVENING...SO HAVE DELAYED THE DECREASE UNTIL LATER TONIGHT.
NORTH WIND SHOULD EVEN REACH THE EASTERN MAGIC VALLEY DURING THE
AFTERNOON. OTHERWISE CIG AND VSBY SHOULD BE EXCELLENT VFR WITH A CIG
POSSIBLE IN THE MID-LEVELS WHERE THE NORTH WIND MEANS UPSLOPE
CONDITIONS...AT KBYI AND KPIH. THIS IS DUE TO A SLOWLY DEPARTING LOW
THAT IS TRACKING THROUGH UT AND SOUTHERN WY/NORTHERN CO. MESSICK
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
LAKE WIND ADVISORY UNTIL 9 PM MDT THIS EVENING AND AGAIN MONDAY FROM
9 AM TO 9 PM MDT FOR IDZ021.
WIND ADVISORY UNTIL 9 PM MDT THIS EVENING FOR IDZ020.
FROST ADVISORY LATE TONIGHT THROUGH MONDAY MORNING FOR IDZ020-021.
FREEZE WATCH FROM LATE MONDAY NIGHT THROUGH TUESDAY MORNING
IDZ017-020-021.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
302 PM CDT SUN MAY 11 2014
.UPDATE...
300 PM CDT
SEVERE THUNDERSTORM WATCH WILL BE COMING OUT SHORTLY FOR MUCH OF
THE ILLINOIS FORECAST AREA INCLUDING CHICAGO. STORM GROWTH WILL
CONTINUE EASTWARD ACROSS THE AREA WITH POTENTIAL DEVELOPMENT
ACROSS WEST CENTRAL ILLINOIS IN THE NEXT 1-2 HRS. SHORT TERM MESO
DISCUSSION TO BE ISSUED SHORTLY.
.DISCUSSION...
300 PM CDT
FORECAST CONCERNS ARE MAINLY ON THE IMMEDIATE SEVERE WEATHER
CHANCES THROUGH EARLY/MID EVENING. ALSO FOCUS ON THE SEVERE
WEATHER POTENTIAL ON MONDAY...PRIMARILY MONDAY LATE AFTERNOON INTO
THE NIGHTTIME PERIOD.
OVERNIGHT INTO MONDAY MORNING...
STRONG UPPER JET WILL PROPAGATE AROUND THE UPPER TROUGH LATE
TONIGHT INTO THE MORNING ON MONDAY AND WITH THAT LEAD TO FURTHER
AMPLIFYING OF THE UPSTREAM RIDGE...INCLUDING BUILDING HEIGHTS
ACROSS MUCH OF THE FORECAST AREA. MUCH OF THE FORCING FOR
RAIN/STORMS IN THIS PERIOD WOULD BE FOCUSED TO THE WEST AND NORTH
IN SUCH A PATTERN. THE STRONG LOW-LEVEL JET WILL AT LEAST IN PART
BE OVER THE AREA...HOWEVER THE NOSE OF IT WILL BE POINTED FURTHER
NORTH. CONVECTIVE CHANCES LOOK MINIMAL AND MAINLY THE NORTHWEST
FORECAST AREA TOWARD ROCKFORD. CHANCES MAY BE INCREASED SOMEWHAT
IF ANY ORGANIZED CONVECTION FROM THE CENTRAL PLAINS WERE TO
PROPAGATE EASTWARD INTO NORTHERN IL...BUT THE GRADUALLY MORE
MERIDIONAL FLOW AND ORIENTATION OF FORECAST CORFIDI VECTORS WOULD
PUSH MUCH OF THE CONVECTION NORTH OF THE AREA. LOW TEMPS WILL BE
BALMY WITH CONTINUED SOUTHERLY FLOW AND HIGH DEW POINT AIR...WITH
SOME PLACES EXPERIENCING SOME WARMING OF TEMPS LATER THIS
EVENING...ESPECIALLY THOSE IMPACTED BY EARLY EVE CONVECTION AND
THOSE COMMUNITIES NEAR THE LAKE SHORE THAT HAD AFTERNOON/EVE
COOLING.
MONDAY AFTERNOON THROUGH TUESDAY...
THE UPPER TROUGH WILL CONTINUE TO AMPLIFY AS THE UPPER JET TO ITS
FRONT AND BACK INTENSITY. A WARM AND MUGGY DAY IS ANTICIPATED
MONDAY. CONVECTIVE INHIBITION ON MONDAY AFTERNOON DOES LOOK TO BE
OVERCOME BUT A FOCUS IS NOT OVERLY EVIDENT IN OUR FORECAST AREA.
GRADUALLY MORE CONVERGENCE AND INCREASING DEEP LAYER MOISTURE AND
UPWARD MOTION IS FORECAST TO MOVE EASTWARD ACROSS MAINLY NORTH
CENTRAL ILLINOIS LATE IN THE DAY INTO EARLY EVE AND EASE ITS WAY
EASTWARD THROUGH THE REMAINDER OF THE NIGHT. THIS LOOKS LIKE A
PERIOD OF STORMS MOVING NORTHEAST WITHIN THE DEEP MOIST PLUME.
THE SEVERE POTENTIAL WOULD SEEM MOST FAVORED WITH THE INITIAL
CONVECTION IN THE LATE AFTERNOON/EVE AND THEN A GENERAL WANING
LATER INTO THE NIGHT.
THE REMAINDER OF THE DISCUSSION TO BE ISSUED SHORTLY.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* SCATTERED THUNDERSTORMS LATE THIS AFTERNOON AND EVENING.
* LAKE BREEZE TURNING WINDS TO THE E/ESE LATE THIS AFTERNOON OR
EVENING.
BMD
//DISCUSSION...UPDATED 18Z...
COMPLEX WEATHER SITUATION WILL BRING A COUPLE DECENT CHANCES FOR
THUNDERSTORMS THIS FORECAST PERIOD...AS WELL AS CHANGING WIND
CONDITIONS. TODAY LOW PRESSURE IS TAKING SHAPE WITH AN ILL-DEFINED
WARM FRONT LIFTING NORTH ACROSS ILLINOIS. THE NEXT FEW HOURS SHOULD
BE RELATIVELY QUIET AT THE TERMINALS WITH A LIGHT SOUTH WIND AND VFR
CONDITIONS. VERY UNSTABLE CONDITIONS ARE DEVELOPING HOWEVER...AND
ALREADY SEEING SIGNS ON SATELLITE IMAGERY OF DEEPENING CLOUD GROWTH
OVER PORTIONS OF MISSOURI AND IOWA. THE THUNDERSTORMS ALREADY IN
PLACE ACROSS SOUTHERN IOWA ARE EXPECTED TO CONTINUE EAST
TODAY...ALONG WITH NEW DEVELOPMENT AHEAD WHICH WILL THEN LIFT
EAST/NORTHEAST ACROSS THE FORECAST AREA. COVERAGE REMAINS
UNCERTAIN...HOWEVER GIVEN THE RELATIVELY WEAK SYNOPTIC FORCING WOULD
EXPECT IT TO BE SOMEWHAT SCATTERED IN NATURE. ANY THUNDERSTORMS
THAT DO DEVELOP HAVE THE POTENTIAL TO BE STRONG TO SEVERE WITH
HAIL AND VERY GUSTY WINDS. WHILE THERE WILL LIKELY BE TIMING
ADJUSTMENTS AS WE NEAR THE EVENT...STILL FEEL THE BEST TIME FOR
TSRA AT THE TERMINALS WILL BE MID TO LATE THIS AFTERNOON INTO THE
EVENING.
IN ADDITION TO CONCERNS FOR TSRA THIS AFTERNOON...THERE ALSO REMAINS
THE POSSIBILITY OF A WIND SHIFT TO THE EAST DUE TO A LAKE BREEZE.
COASTAL OBS REMAIN SOUTHERLY THIS HOUR SO THERE IS NO SIGN OF
DEVELOPMENT YET...AND WINDS WILL BE OF MARGINAL STRENGTH FOR A LAKE
BREEZE TO MAKE IT ALL THE WAY INLAND TO THE TERMINALS. THIS MEANS
THAT THERE IS LOW CERTAINTY ON THE WIND DIRECTION THIS AFTERNOON.
SEVERAL HIGHER RES MODELS CONTINUE TO BRING IT THROUGH SO WOULD
PREFER TO NOT MAKE ANY SIGNIFICANT CHANGES AT THIS TIME. FURTHER
COMPLICATING MATTERS WILL BE THE POTENTIAL FOR THUNDERSTORMS
DEVELOPING ON ANY LAKE BREEZE THAT DEVELOPS WHICH COULD THEN GET
AN ASSIST FROM OUTFLOWS THAT DEVELOP.
ADDITIONAL THUNDERSTORMS ARE POSSIBLE AGAIN MONDAY AFTERNOON/EVENING
AND AGAIN COULD BE STRONG...BUT CURRENT TIMING PLACES IT BEYOND THE
CURRENT FORECAST PERIOD.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM CONFIDENCE IN SCATTERED TSRA AND TIMING.
* MEDIUM CONFIDENCE IN LAKE BREEZE DEVELOPING...LOW CONFIDENCE IN
TIMING THROUGH TERMINALS.
BMD
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...PERIODS OF SHRA/TSRA POSSIBLE.
TUESDAY THROUGH SATURDAY...PERIODIC CHANCES OF SHRA.
KJB
&&
.MARINE...
242 PM...LOW PRESSURE OVER KANSAS WILL MOVE NORTHEAST TO LAKE
SUPERIOR TUESDAY MORNING. AS IT DOES...A WARM FRONT EXTENDING EAST
FROM THE LOW WILL MOVE NORTH ACROSS THE LAKE TONIGHT THROUGH
MONDAY NIGHT...SHIFTING EASTERLY WINDS SOUTHERLY. LOW LEVEL
MOISTURE WILL ALSO BE INCREASING AND AS IT SPREADS ACROSS THE
COOLER LAKE...AREAS OF FOG ARE POSSIBLE AND SOME OF THE FOG MAY
BECOME DENSE. CURRENT WIND SPEEDS ARE FAIRLY LIGHT IN THE 5-15 KT
RANGE AND WILL INCREASE INTO THE 15-25KT RANGE AND REMAIN THERE
UNTIL A COLD FRONT MOVES ACROSS THE LAKE TUESDAY MORNING. THERE IS
A POTENTIAL FOR WINDS TO BE A BIT STRONGER ON MONDAY...ESPECIALLY
WITH THE EASTERLY FLOW NORTH OF THE WARM FRONT ACROSS NORTHERN
LAKE MICHIGAN. THERE REMAINS UNCERTAINTY REGARDING THE POTENTIAL
FOR STRONG NORTHERLY WINDS WEDNESDAY NIGHT INTO THURSDAY AS LOW
PRESSURE DEEPENS MOVING NORTH ACROSS THE GREAT LAKES REGION. THIS
TIME PERIOD WILL NEED TO BE MONITORED FOR HIGHER NORTHERLY WIND
SPEEDS. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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[top]
Area Forecast Discussion
National Weather Service Lincoln IL
248 PM CDT Sun May 11 2014
.DISCUSSION...
ISSUED 248 PM CDT Sun May 11 2014
Air mass destabilizing quickly across central and southeast
Illinois early this afternoon. 18Z upper air sounding from our
office showing CAPE of around 2600 J/kg with no convective
inhibition, although shear values are not especially impressive.
Latest SPC mesoanalysis indicates CAPE`s are over 3000 J/kg south
of I-72, as dew points of 70 degrees have made it as far north as
Taylorville. Warm front extends from southern Nebraska along the
Iowa/Missouri border, but becomes more diffuse in northern
Illinois where it is more of a dew point discontinuity.
Thunderstorms have been percolating most of the day across the
Ohio Valley, and a persistent, small MCS is advancing across Iowa.
Some development has recently started as well across northeast
Missouri south of the main MCS. Has been quiet in our area the
last few hours, but latest radar returns are starting to show
thunderstorms developing between Taylorville and St Louis.
The primary forecast concern remains with the severe weather
threat over the next 24 to 36 hours.
SHORT TERM...Tonight through Tuesday:
Latest runs of the HRRR have been persistent with the Iowa storms
affecting more of the northern third of Illinois, with more
scattered strong/severe storms affecting our area through about
7 pm. Shear parameters don`t really improve any in our area, so
thinking that hail/wind threat will be the primary concerns here
with the tornado threat closer to the warm front. After sunset,
capping of the atmosphere will begin in the warm sector. Have
maintained some 30-40% PoP`s after midnight northwest of the
Illinois River, and slight chances as far east as I-55, with dry
conditions across the southeast half of the forecast area.
Similar convective parameters expected on Monday, with CAPE`s
rising to 2500-3000 J/kg, although shear remains on the low side.
Day2 slight risk basically along and northwest of the Illinois
River, where the shear will be a bit higher as it is closer to the
incoming cold front, and severe weather threat will mainly be mid
afternoon to early evening. With the front slowing down a tad,
will keep any PoP`s east of I-57 around 20% during the day, while
likely PoP`s around 60% found during the afternoon along/west of
the Illinois River. Have maintained the 60-70% PoP`s everywhere
during the night as the front slowly moves through, and over the
eastern CWA on Tuesday with some 80% values south of I-70 Tuesday.
Severe weather threat on Tuesday appears minimal, and would be
near the Indiana border if any did occur.
LONG TERM...Wednesday through Sunday:
A broad upper trough will be dominating much of the eastern half
of the nation into the first part of the weekend, with cool
conditions prevailing. The ECMWF has been persistent with a closed
upper low forming by late Thursday over the Great Lakes, then
lifting northward, while the GFS keeps a more progressive trough.
Toward the end of the weekend, the trough will finally start to
break down as an upper low digs southward across the Pacific
Northwest, causing rising heights over the center of the nation.
Most challenging area in this forecast period is with rain on
Wednesday. The tail end of the NAM is trending toward the solution
favored by the ECMWF and GEM for the last few days, with a surface
low riding northeast along the base of the trough, although the
NAM is much further west with it. The GFS has keep its surface
features much weaker and further east. Have kept the likely PoP`s
on Wednesday across the southeast third of the area, although the
ECMWF/GEM solutions would likely require this to be expanded
further northwest toward the I-55 corridor. Thursday and Friday,
the rain will be much more scattered in nature, as weak troughs
rotate around through the broad upper trough. Rain chances will
diminish this weekend as the upper flow flattens.
Geelhart
&&
.AVIATION...
ISSUED 1248 PM CDT Sun May 11 2014
Thunderstorms currently over south-central Iowa continue to move
E/NE and will enter northwest Illinois after 20z. Current
trajectory should take most of the storms just north of KPIA, so
will only include VCTS between 22z and 02z. Further southeast,
scattered storms are firing in the warm sector across southern
Illinois. HRRR continues to suggest these cells will spread/develop
northward into east-central Illinois this afternoon. Have
therefore included VCTS at the remaining terminals between 21z and
02z, although KSPI may be missed by convection entirely if trends
hold. Gusty S/SE winds will continue through the afternoon and
will remain in the 10 to 15kt range tonight. Meanwhile, a 45kt
925mb jet will develop across the area overnight, warranting a
low-level wind shear mention at the TAF sites. This momentum will
mix to the surface after sunrise, resulting in gusty S/SW winds
Monday morning.
Barnes
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
242 PM CDT SUN MAY 11 2014
.DISCUSSION...
1030 AM CDT
THE FORECAST FOR THIS AFTERNOON INTO THE EVENING REMAINS
CHALLENGING...ALTHOUGH OBSERVATIONAL TRENDS ARE STARTING TO SHOW
THEMSELVES SLIGHTLY AND THE EFFECT OF EARLY MORNING UPSTREAM
CONVECTION IS BEGINNING TO BE RESOLVED BETTER BY HIGH RESOLUTION
GUIDANCE.
ONGOING CONVECTION ACROSS WESTERN IA/FAR NORTHERN MO IS SLOWLY
EVOLVING EAST. WATER VAPOR AND VISIBLE SATELLITE ALONG WITH
REGIONAL RADAR MOSAIC INDICATE THE PROBABLE PRESENCE OF AN MCV OR
AT LEAST A LOW AMPLITUDE PERTURBATION IN FAR SOUTHWEST IA. WHILE
THIS FEATURE IS UNLIKELY TO RAPIDLY MOVE EAST DUE TO LARGE SCALE
HEIGHT RISES...INCREASING LOW-LEVEL THETA-E ADVECTION AHEAD OF
THIS ON THE SYNOPTIC AND MESO SCALES IS EVIDENT AND FORECAST TO
INCREASE. WITH DIMINISHING INHIBITION...THERE SHOULD CONTINUE AT
LEAST SOME EASTWARD DEVELOPMENT/EVOLUTION OF SCATTERED MAINLY
SUB-SEVERE CONVECTION INTO NORTHERN MO/EASTERN IA/WEST CENTRAL IL
THROUGH EARLY AFTERNOON.
BECAUSE OF THE OVERNIGHT CONVECTION FAR DOWNSTATE IL...THE
SURFACE WARM FRONT REMAINS SOMEWHAT DIFFUSE IN IL...BUT BASED ON
THE CLEAR PLACEMENT OF THE FRONT IN FAR SOUTHERN IA AND
OBSERVATIONAL TRENDS IN IL...IT IS LIKELY TO BE STRENGTHENING
NEAR THE I-74 CORRIDOR THROUGH LATE THIS MORNING AND EVOLVING
INTO THE SOUTHERN AND WESTERN CWA EARLY THIS AFTERNOON. THIS WILL
BASICALLY INTERSECT THE AFOREMENTIONED SCATTERED/REMNANT
CONVECTION AND INCREASE THE LIKELIHOOD OF STORMS BECOMING LOWER-
ROOTED TO OUR WEST OR POTENTIALLY IN OUR WESTERN/SOUTHERN CWA BY
MID-AFTERNOON. MLCAPE STILL LOOKS TO BE ON THE ORDER OF OVER 2000
J/KG WITH FAVORABLE SHEAR PROFILES FOR WELL-ORGANIZED AND POSSIBLY
DISCRETE SUPERCELL STORMS. SO BASICALLY MORE TOWARD SCENARIO 3 IN
THE AFOREMENTIONED AFD LOOKS TO BE THE MOST PROBABLE...AND THE
TYPES OF SEVERE WEATHER FAVORED MENTIONED BEFORE REMAIN THE SAME.
HOWEVER...THE OVERALL CONFIDENCE ON COVERAGE OF STORMS DURING THE
MID AFTERNOON THROUGH MID-EVE REMAINS LOW.
THE MOST FAVORABLE TIME FOR STORMS IN THE CHICAGOLAND AREA
REMAINS LATER AFTERNOON INTO THE EARLY EVE. IT IS POSSIBLE THE
CONVERGENCE OF THE LAKE BREEZE ACROSS EASTERN COOK AND INTO LAKE
COUNTIES IL TRIGGERS SOME ISOLATED CONVECTION PRIOR TO THIS...AND
A COUPLE CONVECTIVE ALLOWING MODELS INDICATE THAT.
HAVE MADE SOME ADJUSTMENTS TO THE TEMPORAL RESOLUTION OF
THUNDERSTORM CHANCES...BUT OVERALL NO MAJOR FORECAST CHANGES.
WILL CONTINUE TO MONITOR OBSERVATIONAL TRENDS...INCLUDING 17Z RAOB
LAUNCHES...AS IT RELATES TO CONVECTIVE CHANCES AND MAGNITUDES IN
THE FORECAST AREA.
MTF
//PREV DISCUSSION...
330 AM CDT
SEVERE THUNDERSTORMS POSSIBLE THIS AFTERNOON/EARLY EVENING...HEAT
AND HUMIDITY MAKE AN APPEARANCE...THEN TRANSITION TO COLDER
UNSETTLED WEATHER LATER THIS WEEK.
VERY TRICKY FORECAST FOR TODAY...PARTICULARLY IN LIGHT OF MUCH OF
THE SHORT RANGE MODEL GUIDANCE STRUGGLING TO GET A GOOD HANDLE ON
ONGOING CONVECTION. WARM FRONT CURRENTLY LOCATED NEAR THE I-70
CORRIDOR IS BEING CONVECTIVELY ENHANCED BY MCS THAT IS TRACKING
ACROSS DOWNSTATE ILLINOIS...SOMETHING A LOT OF GUIDANCE HAS MISSED
ALTOGETHER. RISING HEIGHTS AND DEVELOPING SURFACE CYCLONE OVER THE
PLAINS SHOULD ALLOW THE WARM FRONT TO MIX NORTH FAIRLY QUICKLY TODAY
AND LIKELY MOVING INTO NORTHERN ILLINOIS THIS AFTERNOON. WARM FRONT
IS EXPECTED TO BECOME BETTER DEFINED THIS AFTERNOON AS CYCLONE OVER
THE PLAINS ORGANIZES WITH INCREASINGLY STRONG PRESSURE FALLS OVER
IOWA LIKELY TO RESULT IN A BACKING OF THE LOW LEVEL WINDS THIS
AFTERNOON...ESPECIALLY NORTH OF THE FRONT AT THE SURFACE.
TO ME THERE LOOKS TO BE 3 MOST PROBABLE POSSIBLE SCENARIOS
CONVECTIVELY TODAY. FIRST...THE LEAST LIKELY SEEMS TO BE THE CAP
HOLDING STRONG AND NO OR ONLY VERY ISOLATED THUNDERSTORMS FORMING. A
SECOND POSSIBLE SCENARIO THAT SEVERAL OF THE CONVECTIVE ALLOWING
MODELS (CAMS) SUGGEST WOULD BE AN MCS ORGANIZING OVER IOWA TOWARD
SUNRISE...THEN MOVING EAST INTO NORTHERN ILLINOIS THIS AFTERNOON.
CONVECTIVE TRENDS CURRENT DON`T SEEM TO FAVOR THIS SCENARIO WITH
STORMS OVER THE EASTERN PLAINS EAST INTO MISSOURI WEAKENING WITH
RENEWED DEVELOPMENT FARTHER WEST OVER NEBRASKA AND KANSAS PRETTY
UNLIKELY TO REACH OUR AREA THIS AFTERNOON. THE FINAL POSSIBLE
SCENARIO...AND THE ONE THAT SEEMS MOST PLAUSIBLE...WOULD BE
SCATTERED THUNDERSTORMS DEVELOPING NEAR THE SHARPENING WARM FRONT
THIS AFTERNOON AS STRONG HEATING ERODES CONVECTIVE INHIBITION.
SEVERE THREAT THIS AFTERNOON/EARLY THIS EVENING WILL OBVIOUSLY BE
DEPENDENT ON HOW CONVECTION EVOLVES. FOR INSTANCE...SCENARIO 2 WITH
THE REMNANT MCS WOULD TEND TO FAVOR A MULTICELL WIND/HAIL THREAT.
SCENARIO 3 IS SOMEWHAT MORE CONCERNING...GIVEN THE SOMEWHAT NEBULOUS
FORCING WOULD EXPECT CONVECTION TO DEVELOP TO BE MORE SCATTERED AND
CELLULAR IN NATURE. THERE ARE CERTAINLY SOME NOTABLE DIFFERENCES IN
THE MODELS WITH RESPECT TO SHEAR PROFILES THIS AFTERNOON...BUT ALL
GUIDANCE SUGGESTS AND VEERING AND SLOWLY INCREASING MID LEVEL
FLOW...WITH BACKING LOW LEVEL AND SURFACE FLOW INCREASING HODOGRAPH
SIZES LATE THIS AFTERNOON. MANY OF THE MODELS ACTUALLY SHOW A VERY
NICE VEERING/INCREASING WIND PROFILE FROM THE SFC-6KM QUITE
FAVORABLE FOR SUPERCELLS. ALSO OF CONCERN IS WIND PROFILES WOULD
FAVOR RIGHT MOVING SUPERCELLS WITH AN EASTERLY MOTION ROUGHLY
PARALLEL TO THE WARM FRONT. FAR MORE UNCERTAINTY EXISTS IN OUR AREA
COMPARED TO POINTS WEST IN THE MODERATE RISK OVER IOWA AND
NEBRASKA...BUT IF CONVECTION OCCURS AND MODE IS FAVORABLE THEN THERE
MAY WELL BE A SEVERAL HOUR LONG WINDOW FAVORABLE CONDITIONS FOR
SUPERCELL(S) WITH A LARGE HAIL AND TORNADO POTENTIAL LOCALLY LATE
THIS AFTERNOON AND EVERY EARLY THIS EVENING.
OTHER FORECAST CONCERNS TODAY INCLUDE CLOUD COVER AND TEMPS. A LOT
OF CLEAR SKIES HERE WEST INTO IOWA REALLY RAISE DOUBTS ABOUT HOW
CLOUDY MUCH OF THE GUIDANCE HAS THINGS TODAY. CONVECTIVE DEBRIS FROM
ACTIVITY OVER MISSOURI COULD LEAD TO SOME CLOUDINESS THIS
MORNING...BUT QUICKLY WARMING CLOUD TOPS ALREADY SUGGEST THAT THIS
MAY NOT BE MUCH OF A FACTOR. ASSUMING WE GET A FAIR AMOUNT OF
SUNSHINE...WHICH SEEMS PRETTY LIKELY...THEN TEMPERATURES COULD
EASILY GET OUT OF HAND. HAVE RAISED HIGHS SEVERAL DEGREES...BUT
WOULD NOT BE SURPRISING TO SEE TEMPS WELL INTO 80S THIS AFTERNOON.
AS CYCLONE DEEPENS AND PRESSURE FALLS INCREASE TO OUR WEST THE
SYNOPTIC GRADIENT IS LIKELY TO BACK MORE SOUTHEASTERLY WHICH SHOULD
ALLOW A LAKE BREEZE TO COME CHARGING WEST INTO NE IL SENDING TEMPS
DROPPING. HIGHER DEWPOINTS WILL PROBABLY STILL BE SOUTH OF THIS AREA
SO MOST LIKELY JUST A RESPECTABLE TEMP DROP AND NOT A LAKE SHORE FOG
PROBLEMS.
WARM FRONT LIKELY TO BLAST NORTH INTO WISCONSIN TONIGHT SENDING
TEMPS SOARING IN THE LAKE COOLED AREAS OF NE IL THIS EVENING AND
ALLOWING TEMPS TO REMAIN UNSEASONABLY WARM ELSEWHERE. FOCUS FOR
CONVECTION TONIGHT SHOULD SHIFT INTO WISCONSIN WITH MAJORITY OF OUR
AREA REMAINING DRY...THOUGH AM RELUCTANT TO REMOVE POPS ALTOGETHER
GIVEN THE INHERENT UNCERTAINTIES DEALING WITH CONVECTIVE EVOLUTION.
MONDAY LOOKS POISED TO BE BREEZY AND UNSEASONABLY WARM AND RATHER
HUMID AS WE RESIDE FIRMLY IN THE WARM SECTOR OF THE CYCLONE. QUICKLY
WARMING TEMPS ALOFT WITH CONTINUED HEIGHT RISES SUGGEST THAT ANY
LEFT OVER CONVECTION SHOULD FADE BEFORE MAKING IT INTO OR VERY FAR
EAST ACROSS OUR CWA MONDAY MORNING. HAVE BUMPED UP TEMPS INTO THE
MID TO UPPER 80S...THOUGH WITH ENOUGH SUNSHINE SOME AREAS COULD
EASILY REACH 90 DEGREES AGAIN GIVEN 850/925MB TEMPS PROGGED TO BE
PRETTY SIMILAR TO WHAT WE SAW THURSDAY. BY AFTERNOON RAIN CHANCES
LOOK SLIM WITH BETTER FORCING WELL WEST OF THE CWA ACROSS IOWA WHERE
STRONG TO SEVERE THUNDERSTORMS ARE LIKELY TO DEVELOP LATE MONDAY
AFTERNOON.
THE LEFT OVERS OF THESE STORMS ARE LIKELY TO MOVE SLOWLY EASTWARD
TOWARD OUR CWA...BUT SHOULDNT ARRIVE UNTIL AFTER DARK AND PROBABLY
WELL AFTER DARK. STABILIZING BOUNDARY LAYER/INCREASING
CINH...MARGINAL SHEAR PROFILES...AND BETTER UPPER FORCING LAGGING TO
THE WEST SUGGEST THAT THE STORMS SHOULD BE IN A WEAKENING PHASE AS
THEY MOVE IN AND THAT LEAVES ME FAR FROM TINGLY ABOUT ANY MEANINGFUL
SEVERE THREAT MONDAY NIGHT.
STILL LOOKS TO BE A MUCH...MUCH COLDER PATTERN SETTING UP FOR THE
MIDDLE AND END OF THE WEEK WITH AN ANOMALOUSLY STRONG UPPER TROUGH
BECOMING ESTABLISHED OVER THE REGION. MEDIUM RANGE MODELS CONTINUE
TO DIFFER SUBSTANTIALLY IN THEIR HANDLING OF THE SMALLER SCALE WAVES
AND SUBSEQUENT BETTER SHOWER CHANCES...SO LEFT WITH LITTLE CHOICE
THAN PERIOD AFTER PERIOD OF SHOWER CHANCES WEDNESDAY ONWARD.
IZZI
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* SCATTERED THUNDERSTORMS LATE THIS AFTERNOON AND EVENING.
* LAKE BREEZE TURNING WINDS TO THE E/ESE LATE THIS AFTERNOON OR
EVENING.
BMD
//DISCUSSION...UPDATED 18Z...
COMPLEX WEATHER SITUATION WILL BRING A COUPLE DECENT CHANCES FOR
THUNDERSTORMS THIS FORECAST PERIOD...AS WELL AS CHANGING WIND
CONDITIONS. TODAY LOW PRESSURE IS TAKING SHAPE WITH AN ILL-DEFINED
WARM FRONT LIFTING NORTH ACROSS ILLINOIS. THE NEXT FEW HOURS SHOULD
BE RELATIVELY QUIET AT THE TERMINALS WITH A LIGHT SOUTH WIND AND VFR
CONDITIONS. VERY UNSTABLE CONDITIONS ARE DEVELOPING HOWEVER...AND
ALREADY SEEING SIGNS ON SATELLITE IMAGERY OF DEEPENING CLOUD GROWTH
OVER PORTIONS OF MISSOURI AND IOWA. THE THUNDERSTORMS ALREADY IN
PLACE ACROSS SOUTHERN IOWA ARE EXPECTED TO CONTINUE EAST
TODAY...ALONG WITH NEW DEVELOPMENT AHEAD WHICH WILL THEN LIFT
EAST/NORTHEAST ACROSS THE FORECAST AREA. COVERAGE REMAINS
UNCERTAIN...HOWEVER GIVEN THE RELATIVELY WEAK SYNOPTIC FORCING WOULD
EXPECT IT TO BE SOMEWHAT SCATTERED IN NATURE. ANY THUNDERSTORMS
THAT DO DEVELOP HAVE THE POTENTIAL TO BE STRONG TO SEVERE WITH
HAIL AND VERY GUSTY WINDS. WHILE THERE WILL LIKELY BE TIMING
ADJUSTMENTS AS WE NEAR THE EVENT...STILL FEEL THE BEST TIME FOR
TSRA AT THE TERMINALS WILL BE MID TO LATE THIS AFTERNOON INTO THE
EVENING.
IN ADDITION TO CONCERNS FOR TSRA THIS AFTERNOON...THERE ALSO REMAINS
THE POSSIBILITY OF A WIND SHIFT TO THE EAST DUE TO A LAKE BREEZE.
COASTAL OBS REMAIN SOUTHERLY THIS HOUR SO THERE IS NO SIGN OF
DEVELOPMENT YET...AND WINDS WILL BE OF MARGINAL STRENGTH FOR A LAKE
BREEZE TO MAKE IT ALL THE WAY INLAND TO THE TERMINALS. THIS MEANS
THAT THERE IS LOW CERTAINTY ON THE WIND DIRECTION THIS AFTERNOON.
SEVERAL HIGHER RES MODELS CONTINUE TO BRING IT THROUGH SO WOULD
PREFER TO NOT MAKE ANY SIGNIFICANT CHANGES AT THIS TIME. FURTHER
COMPLICATING MATTERS WILL BE THE POTENTIAL FOR THUNDERSTORMS
DEVELOPING ON ANY LAKE BREEZE THAT DEVELOPS WHICH COULD THEN GET
AN ASSIST FROM OUTFLOWS THAT DEVELOP.
ADDITIONAL THUNDERSTORMS ARE POSSIBLE AGAIN MONDAY AFTERNOON/EVENING
AND AGAIN COULD BE STRONG...BUT CURRENT TIMING PLACES IT BEYOND THE
CURRENT FORECAST PERIOD.
BMD
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MEDIUM CONFIDENCE IN SCATTERED TSRA AND TIMING.
* MEDIUM CONFIDENCE IN LAKE BREEZE DEVELOPING...LOW CONFIDENCE IN
TIMING THROUGH TERMINALS.
BMD
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...PERIODS OF SHRA/TSRA POSSIBLE.
TUESDAY THROUGH SATURDAY...PERIODIC CHANCES OF SHRA.
KJB
&&
.MARINE...
242 PM...LOW PRESSURE OVER KANSAS WILL MOVE NORTHEAST TO LAKE
SUPERIOR TUESDAY MORNING. AS IT DOES...A WARM FRONT EXTENDING EAST
FROM THE LOW WILL MOVE NORTH ACROSS THE LAKE TONIGHT THROUGH
MONDAY NIGHT...SHIFTING EASTERLY WINDS SOUTHERLY. LOW LEVEL
MOISTURE WILL ALSO BE INCREASING AND AS IT SPREADS ACROSS THE
COOLER LAKE...AREAS OF FOG ARE POSSIBLE AND SOME OF THE FOG MAY
BECOME DENSE. CURRENT WIND SPEEDS ARE FAIRLY LIGHT IN THE 5-15 KT
RANGE AND WILL INCREASE INTO THE 15-25KT RANGE AND REMAIN THERE
UNTIL A COLD FRONT MOVES ACROSS THE LAKE TUESDAY MORNING. THERE IS
A POTENTIAL FOR WINDS TO BE A BIT STRONGER ON MONDAY...ESPECIALLY
WITH THE EASTERLY FLOW NORTH OF THE WARM FRONT ACROSS NORTHERN
LAKE MICHIGAN. THERE REMAINS UNCERTAINTY REGARDING THE POTENTIAL
FOR STRONG NORTHERLY WINDS WEDNESDAY NIGHT INTO THURSDAY AS LOW
PRESSURE DEEPENS MOVING NORTH ACROSS THE GREAT LAKES REGION. THIS
TIME PERIOD WILL NEED TO BE MONITORED FOR HIGHER NORTHERLY WIND
SPEEDS. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
1248 PM CDT Sun May 11 2014
.DISCUSSION...
ISSUED 1044 AM CDT Sun May 11 2014
Warm front continues to lift northward through the region this
morning. Boundary is becoming difficult to analyze, as winds have
become southerly across central Illinois, while the tightest dewpoint
gradient remains further south across central Missouri into far
southern Illinois. Cluster of convection is currently ongoing
north of the warm front over southwest Iowa. We will need to keep
a close eye on these storms as they track along the boundary
today. Some models develop this convection eastward into central
Illinois between 1 pm and 4 pm, while the HRRR continues to take
it more northeastward into northern Illinois, generally tracking
along the 850mb warm front. Since convective evolution remains
uncertain, will not be making any changes to the going forecast at
this time. POPs will be highest across the far N/NW KILX CWA in
closer proximity to the upper front and the potential track of the
Iowa convection. Further south into the warm sector, any storms
that fire south of the I-72 corridor will be much more scattered
in nature, so lower POPs are warranted there.
Barnes
&&
.AVIATION...
ISSUED 1248 PM CDT Sun May 11 2014
Thunderstorms currently over south-central Iowa continue to move
E/NE and will enter northwest Illinois after 20z. Current
trajectory should take most of the storms just north of KPIA, so
will only include VCTS between 22z and 02z. Further southeast,
scattered storms are firing in the warm sector across southern
Illinois. HRRR continues to suggest these cells will spread/develop
northward into east-central Illinois this afternoon. Have
therefore included VCTS at the remaining terminals between 21z and
02z, although KSPI may be missed by convection entirely if trends
hold. Gusty S/SE winds will continue through the afternoon and
will remain in the 10 to 15kt range tonight. Meanwhile, a 45kt
925mb jet will develop across the area overnight, warranting a
low-level wind shear mention at the TAF sites. This momentum will
mix to the surface after sunrise, resulting in gusty S/SW winds
Monday morning.
Barnes
&&
.PREV DISCUSSION...
ISSUED 330 AM CDT Sun May 11 2014
SHORT TERM...Today through Wednesday night
MCS with showers and scattered thunderstorms from I-72 south to
I-64 early this morning with isolated strong to severe storms
with hail and gusty winds of 40-60 mph moving east at 40 mph
toward the Wabash river. Models show these showers and
thunderstorms diminishing by sunrise as warm front lifts northward
across central and into northern IL during today. Kept a chance of
convection today and tonight though best chances northern areas.
SPC has slight chance of severe storms over most of CWA today and
early evening with moderate risk over central/southern IA into se
NE and north-central KS. SPC has slight risk of severe storms nw of
the IL river late Monday afternoon and Monday evening as cold
front approaches the MS river valley. Warmer highs in the 80s
today and Monday and more humid with dewpoints in the 60s.
Highest chances of convection will be Monday night western areas
and eastern IL Tue with passage of cold front. SPC has 5% risk of
severe storms Tue over far eastern IL with passage of cold front
though better chances further east over IN and lower MI.
Models continue to show surface low pressure ejecting ne from
southern MS river valley into the Ohio river valley Wed and qpf
moving back over central and especially eastern IL and have
increase pops on Wed and Wed evening. Large upper level trof
settles into the Midwest during mid week and have temps cooling
below normal by Wed/Thu with highs in the lower 60s and lows in
the 40s Wed night & Thu night.
LONG TERM...Thursday through Sunday
Extended models have been consistent in showing a large upper
level trof over the Great Lakes region and Midwest during mid/late week
and gradually pulls away from IL by Sunday. Below normal
temperatures expected during mid and late week with temps a good
10 degrees below normal. Instability isolated light showers
possible each day especially during the afternoon and early
evening hours until sunset due to upper level trof and a few
disturbances pivoting through the trof.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1102 AM CDT SUN MAY 11 2014
.DISCUSSION...
1030 AM CDT
THE FORECAST FOR THIS AFTERNOON INTO THE EVENING REMAINS
CHALLENGING...ALTHOUGH OBSERVATIONAL TRENDS ARE STARTING TO SHOW
THEMSELVES SLIGHTLY AND THE EFFECT OF EARLY MORNING UPSTREAM
CONVECTION IS BEGINNING TO BE RESOLVED BETTER BY HIGH RESOLUTION
GUIDANCE.
ONGOING CONVECTION ACROSS WESTERN IA/FAR NORTHERN MO IS SLOWLY
EVOLVING EAST. WATER VAPOR AND VISIBLE SATELLITE ALONG WITH
REGIONAL RADAR MOSAIC INDICATE THE PROBABLE PRESENCE OF AN MCV OR
AT LEAST A LOW AMPLITUDE PERTURBATION IN FAR SOUTHWEST IA. WHILE
THIS FEATURE IS UNLIKELY TO RAPIDLY MOVE EAST DUE TO LARGE SCALE
HEIGHT RISES...INCREASING LOW-LEVEL THETA-E ADVECTION AHEAD OF
THIS ON THE SYNOPTIC AND MESO SCALES IS EVIDENT AND FORECAST TO
INCREASE. WITH DIMINISHING INHIBITION...THERE SHOULD CONTINUE AT
LEAST SOME EASTWARD DEVELOPMENT/EVOLUTION OF SCATTERED MAINLY
SUB-SEVERE CONVECTION INTO NORTHERN MO/EASTERN IA/WEST CENTRAL IL
THROUGH EARLY AFTERNOON.
BECAUSE OF THE OVERNIGHT CONVECTION FAR DOWNSTATE IL...THE
SURFACE WARM FRONT REMAINS SOMEWHAT DIFFUSE IN IL...BUT BASED ON
THE CLEAR PLACEMENT OF THE FRONT IN FAR SOUTHERN IA AND
OBSERVATIONAL TRENDS IN IL...IT IS LIKELY TO BE STRENGTHENING
NEAR THE I-74 CORRIDOR THROUGH LATE THIS MORNING AND EVOLVING
INTO THE SOUTHERN AND WESTERN CWA EARLY THIS AFTERNOON. THIS WILL
BASICALLY INTERSECT THE AFOREMENTIONED SCATTERED/REMNANT
CONVECTION AND INCREASE THE LIKELIHOOD OF STORMS BECOMING LOWER-
ROOTED TO OUR WEST OR POTENTIALLY IN OUR WESTERN/SOUTHERN CWA BY
MID-AFTERNOON. MLCAPE STILL LOOKS TO BE ON THE ORDER OF OVER 2000
J/KG WITH FAVORABLE SHEAR PROFILES FOR WELL-ORGANIZED AND POSSIBLY
DISCRETE SUPERCELL STORMS. SO BASICALLY MORE TOWARD SCENARIO 3 IN
THE AFOREMENTIONED AFD LOOKS TO BE THE MOST PROBABLE...AND THE
TYPES OF SEVERE WEATHER FAVORED MENTIONED BEFORE REMAIN THE SAME.
HOWEVER...THE OVERALL CONFIDENCE ON COVERAGE OF STORMS DURING THE
MID AFTERNOON THROUGH MID-EVE REMAINS LOW.
THE MOST FAVORABLE TIME FOR STORMS IN THE CHICAGOLAND AREA
REMAINS LATER AFTERNOON INTO THE EARLY EVE. IT IS POSSIBLE THE
CONVERGENCE OF THE LAKE BREEZE ACROSS EASTERN COOK AND INTO LAKE
COUNTIES IL TRIGGERS SOME ISOLATED CONVECTION PRIOR TO THIS...AND
A COUPLE CONVECTIVE ALLOWING MODELS INDICATE THAT.
HAVE MADE SOME ADJUSTMENTS TO THE TEMPORAL RESOLUTION OF
THUNDERSTORM CHANCES...BUT OVERALL NO MAJOR FORECAST CHANGES.
WILL CONTINUE TO MONITOR OBSERVATIONAL TRENDS...INCLUDING 17Z RAOB
LAUNCHES...AS IT RELATES TO CONVECTIVE CHANCES AND MAGNITUDES IN
THE FORECAST AREA.
MTF
//PREV DISCUSSION...
330 AM CDT
SEVERE THUNDERSTORMS POSSIBLE THIS AFTERNOON/EARLY EVENING...HEAT
AND HUMIDITY MAKE AN APPEARANCE...THEN TRANSITION TO COLDER
UNSETTLED WEATHER LATER THIS WEEK.
VERY TRICKY FORECAST FOR TODAY...PARTICULARLY IN LIGHT OF MUCH OF
THE SHORT RANGE MODEL GUIDANCE STRUGGLING TO GET A GOOD HANDLE ON
ONGOING CONVECTION. WARM FRONT CURRENTLY LOCATED NEAR THE I-70
CORRIDOR IS BEING CONVECTIVELY ENHANCED BY MCS THAT IS TRACKING
ACROSS DOWNSTATE ILLINOIS...SOMETHING A LOT OF GUIDANCE HAS MISSED
ALTOGETHER. RISING HEIGHTS AND DEVELOPING SURFACE CYCLONE OVER THE
PLAINS SHOULD ALLOW THE WARM FRONT TO MIX NORTH FAIRLY QUICKLY TODAY
AND LIKELY MOVING INTO NORTHERN ILLINOIS THIS AFTERNOON. WARM FRONT
IS EXPECTED TO BECOME BETTER DEFINED THIS AFTERNOON AS CYCLONE OVER
THE PLAINS ORGANIZES WITH INCREASINGLY STRONG PRESSURE FALLS OVER
IOWA LIKELY TO RESULT IN A BACKING OF THE LOW LEVEL WINDS THIS
AFTERNOON...ESPECIALLY NORTH OF THE FRONT AT THE SURFACE.
TO ME THERE LOOKS TO BE 3 MOST PROBABLE POSSIBLE SCENARIOS
CONVECTIVELY TODAY. FIRST...THE LEAST LIKELY SEEMS TO BE THE CAP
HOLDING STRONG AND NO OR ONLY VERY ISOLATED THUNDERSTORMS FORMING. A
SECOND POSSIBLE SCENARIO THAT SEVERAL OF THE CONVECTIVE ALLOWING
MODELS (CAMS) SUGGEST WOULD BE AN MCS ORGANIZING OVER IOWA TOWARD
SUNRISE...THEN MOVING EAST INTO NORTHERN ILLINOIS THIS AFTERNOON.
CONVECTIVE TRENDS CURRENT DON`T SEEM TO FAVOR THIS SCENARIO WITH
STORMS OVER THE EASTERN PLAINS EAST INTO MISSOURI WEAKENING WITH
RENEWED DEVELOPMENT FARTHER WEST OVER NEBRASKA AND KANSAS PRETTY
UNLIKELY TO REACH OUR AREA THIS AFTERNOON. THE FINAL POSSIBLE
SCENARIO...AND THE ONE THAT SEEMS MOST PLAUSIBLE...WOULD BE
SCATTERED THUNDERSTORMS DEVELOPING NEAR THE SHARPENING WARM FRONT
THIS AFTERNOON AS STRONG HEATING ERODES CONVECTIVE INHIBITION.
SEVERE THREAT THIS AFTERNOON/EARLY THIS EVENING WILL OBVIOUSLY BE
DEPENDENT ON HOW CONVECTION EVOLVES. FOR INSTANCE...SCENARIO 2 WITH
THE REMNANT MCS WOULD TEND TO FAVOR A MULTICELL WIND/HAIL THREAT.
SCENARIO 3 IS SOMEWHAT MORE CONCERNING...GIVEN THE SOMEWHAT NEBULOUS
FORCING WOULD EXPECT CONVECTION TO DEVELOP TO BE MORE SCATTERED AND
CELLULAR IN NATURE. THERE ARE CERTAINLY SOME NOTABLE DIFFERENCES IN
THE MODELS WITH RESPECT TO SHEAR PROFILES THIS AFTERNOON...BUT ALL
GUIDANCE SUGGESTS AND VEERING AND SLOWLY INCREASING MID LEVEL
FLOW...WITH BACKING LOW LEVEL AND SURFACE FLOW INCREASING HODOGRAPH
SIZES LATE THIS AFTERNOON. MANY OF THE MODELS ACTUALLY SHOW A VERY
NICE VEERING/INCREASING WIND PROFILE FROM THE SFC-6KM QUITE
FAVORABLE FOR SUPERCELLS. ALSO OF CONCERN IS WIND PROFILES WOULD
FAVOR RIGHT MOVING SUPERCELLS WITH AN EASTERLY MOTION ROUGHLY
PARALLEL TO THE WARM FRONT. FAR MORE UNCERTAINTY EXISTS IN OUR AREA
COMPARED TO POINTS WEST IN THE MODERATE RISK OVER IOWA AND
NEBRASKA...BUT IF CONVECTION OCCURS AND MODE IS FAVORABLE THEN THERE
MAY WELL BE A SEVERAL HOUR LONG WINDOW FAVORABLE CONDITIONS FOR
SUPERCELL(S) WITH A LARGE HAIL AND TORNADO POTENTIAL LOCALLY LATE
THIS AFTERNOON AND EVERY EARLY THIS EVENING.
OTHER FORECAST CONCERNS TODAY INCLUDE CLOUD COVER AND TEMPS. A LOT
OF CLEAR SKIES HERE WEST INTO IOWA REALLY RAISE DOUBTS ABOUT HOW
CLOUDY MUCH OF THE GUIDANCE HAS THINGS TODAY. CONVECTIVE DEBRIS FROM
ACTIVITY OVER MISSOURI COULD LEAD TO SOME CLOUDINESS THIS
MORNING...BUT QUICKLY WARMING CLOUD TOPS ALREADY SUGGEST THAT THIS
MAY NOT BE MUCH OF A FACTOR. ASSUMING WE GET A FAIR AMOUNT OF
SUNSHINE...WHICH SEEMS PRETTY LIKELY...THEN TEMPERATURES COULD
EASILY GET OUT OF HAND. HAVE RAISED HIGHS SEVERAL DEGREES...BUT
WOULD NOT BE SURPRISING TO SEE TEMPS WELL INTO 80S THIS AFTERNOON.
AS CYCLONE DEEPENS AND PRESSURE FALLS INCREASE TO OUR WEST THE
SYNOPTIC GRADIENT IS LIKELY TO BACK MORE SOUTHEASTERLY WHICH SHOULD
ALLOW A LAKE BREEZE TO COME CHARGING WEST INTO NE IL SENDING TEMPS
DROPPING. HIGHER DEWPOINTS WILL PROBABLY STILL BE SOUTH OF THIS AREA
SO MOST LIKELY JUST A RESPECTABLE TEMP DROP AND NOT A LAKE SHORE FOG
PROBLEMS.
WARM FRONT LIKELY TO BLAST NORTH INTO WISCONSIN TONIGHT SENDING
TEMPS SOARING IN THE LAKE COOLED AREAS OF NE IL THIS EVENING AND
ALLOWING TEMPS TO REMAIN UNSEASONABLY WARM ELSEWHERE. FOCUS FOR
CONVECTION TONIGHT SHOULD SHIFT INTO WISCONSIN WITH MAJORITY OF OUR
AREA REMAINING DRY...THOUGH AM RELUCTANT TO REMOVE POPS ALTOGETHER
GIVEN THE INHERENT UNCERTAINTIES DEALING WITH CONVECTIVE EVOLUTION.
MONDAY LOOKS POISED TO BE BREEZY AND UNSEASONABLY WARM AND RATHER
HUMID AS WE RESIDE FIRMLY IN THE WARM SECTOR OF THE CYCLONE. QUICKLY
WARMING TEMPS ALOFT WITH CONTINUED HEIGHT RISES SUGGEST THAT ANY
LEFT OVER CONVECTION SHOULD FADE BEFORE MAKING IT INTO OR VERY FAR
EAST ACROSS OUR CWA MONDAY MORNING. HAVE BUMPED UP TEMPS INTO THE
MID TO UPPER 80S...THOUGH WITH ENOUGH SUNSHINE SOME AREAS COULD
EASILY REACH 90 DEGREES AGAIN GIVEN 850/925MB TEMPS PROGGED TO BE
PRETTY SIMILAR TO WHAT WE SAW THURSDAY. BY AFTERNOON RAIN CHANCES
LOOK SLIM WITH BETTER FORCING WELL WEST OF THE CWA ACROSS IOWA WHERE
STRONG TO SEVERE THUNDERSTORMS ARE LIKELY TO DEVELOP LATE MONDAY
AFTERNOON.
THE LEFT OVERS OF THESE STORMS ARE LIKELY TO MOVE SLOWLY EASTWARD
TOWARD OUR CWA...BUT SHOULDNT ARRIVE UNTIL AFTER DARK AND PROBABLY
WELL AFTER DARK. STABILIZING BOUNDARY LAYER/INCREASING
CINH...MARGINAL SHEAR PROFILES...AND BETTER UPPER FORCING LAGGING TO
THE WEST SUGGEST THAT THE STORMS SHOULD BE IN A WEAKENING PHASE AS
THEY MOVE IN AND THAT LEAVES ME FAR FROM TINGLY ABOUT ANY MEANINGFUL
SEVERE THREAT MONDAY NIGHT.
STILL LOOKS TO BE A MUCH...MUCH COLDER PATTERN SETTING UP FOR THE
MIDDLE AND END OF THE WEEK WITH AN ANOMALOUSLY STRONG UPPER TROUGH
BECOMING ESTABLISHED OVER THE REGION. MEDIUM RANGE MODELS CONTINUE
TO DIFFER SUBSTANTIALLY IN THEIR HANDLING OF THE SMALLER SCALE WAVES
AND SUBSEQUENT BETTER SHOWER CHANCES...SO LEFT WITH LITTLE CHOICE
THAN PERIOD AFTER PERIOD OF SHOWER CHANCES WEDNESDAY ONWARD.
IZZI
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* SOUTH WINDS TODAY...SHIFTING EAST-SOUTHEASTERLY AFTER 23 UTC
THIS AFTERNOON.
* CHANCES AND TIMING OF SCT TSRA THIS AFTERNOON/EVENING...BEST
CHANCES BETWEEN 23 AND 03 UTC.
* LLWS POTENTIAL LATE SUNDAY EVENING WITH 1500-2000 FT WIND SSW
40-50 KT.
KJB/BMD
//DISCUSSION...UPDATED 12Z...
THE MAIN FORECAST CONCERNS TODAY WILL CONTINUE TO FOCUS ON THE
CHANCES AND TIMING FOR CONVECTION IN AND NEAR THE TERMINALS THIS
AFTERNOON/EVENING...AND ALSO WIND DIRECTIONS...ESPECIALLY LATER THIS
AFTERNOON AND EVENING TO THE NORTH OF AN APPROACHING WARM FRONTAL
ZONE.
AN INCREASINGLY UNSETTLED WEATHER PATTERN WILL BE SETTING UP
ACROSS THE REGION THROUGH THE DAY AS A BROAD AREA OF LOW PRESSURE
ACROSS THE PLAINS BEGINS TO CONSOLIDATE AND MOVE TOWARDS THE MID
MISSOURI VALLEY LATER TODAY AND TONIGHT. AS THIS OCCURS...AN
ASSOCIATED WARM FRONTAL ZONE WILL BEGIN TO LIFT NORTHWARD ACROSS
CENTRAL ILLINOIS TODAY...THEN SURGE NORTHWARD ACROSS THE REGION
LATER THIS EVENING. AN INCREASINGLY WARM...MOIST AND UNSTABLE
ATMOSPHERE WILL LIKELY ACCOMPANY THIS WARM FRONT...SETTING UP THE
STAGE FOR A POSSIBLE PERIOD OF SOME SCATTERED CONVECTIVE ACTIVITY
LATER THIS AFTERNOON AND EVENING. THE BEST THREAT FOR CONVECTIVE
ACTIVITY OVER OR NEAR THE TERMINALS APPEARS TO FROM AROUND 22 UTC
THROUGH 02 UTC THIS EVENING. ALTHOUGH THE ACTUAL CHANCES OF
CONVECTIVE ACTIVITY HAVE NOT REALLY CHANGED...I HAVE REPLACED THE
PROB 30 GROUP WITH A VCTS AND TEMPO GROUP FOR THUNDERSTORMS. THE
MAIN REASON FOR DOING THIS IS THAT I AM NOT COMFORTABLE NOT HAVING
A MENTION OF THUNDER IN THE TAFS...AND RULES PROHIBIT THE USE OF A
PROB 30 GROUP WITHIN THE FIRST 9 HOURS OF THE TAF.
THE CONVECTIVE THREAT LOOKS TO SHIFT NORTHWARD ACROSS SOUTHERN
WISCONSIN LATER THIS EVENING AND OVERNIGHT AS THE WARM FRONT
SURGES NORTHWARD...SO IT APPEARS NO ADDITIONAL MENTIONS OF
CONVECTION ARE NEEDED IN THE TAF TONIGHT.
THE OTHER CONCERN LATER TODAY WILL BE THE WINDS. FORECAST GUIDANCE
INDICATES THAT A SOUTH-SOUTHWESTERLY WIND COMPONENT EARLY IN THE
DAY WILL BACK MORE EAST-SOUTHEASTERLY LATER IN THE AFTERNOON AND
EVENING ACROSS NORTHERN ILLINOIS IN RESPONSE TO PRESSURE FALLS
ACROSS IOWA AND NORTHWESTERN ILLINOIS. THIS MAY PROMOTE A LAKE
BREEZE TO DEVELOP AND MOVE INLAND...POSSIBLY CAUSING THE WINDS TO
BECOME DUE EASTERLY AT THE EASTERN TAF SITES FOR A PERIOD EARLY
EVENING. THE WINDS WILL EVENTUALLY SHIFT BACK OUT OF THE SOUTH
AGAIN TONIGHT AFTER THE WARM FRONT SURGES NORTH OF THE TERMINALS.
SOME LOW LEVEL WIND SHEAR COULD ALSO SET UP FOR A PERIOD LATE
TONIGHT AS A SOUTH-SOUTHWESTERLY 45+ KT LOW LEVEL SETS UP OVER THE
REGION.
KJB
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* LOW WITH OCCURRENCE/TIMING OF EAST-SOUTHEASTERLY WIND SHIFT THIS
AFTERNOON/EVENING.
* MEDIUM-LOW CONFIDENCE IN TSRA TIMING/COVERAGE THIS
AFTERNOON/EVE.
* MEDIUM CONFIDENCE IN LLWS TONIGHT.
KJB/BMD
//OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z...
MONDAY NIGHT...PERIODS OF SHRA/TSRA POSSIBLE.
TUESDAY THROUGH SATURDAY...PERIODIC CHANCES OF SHRA.
KJB
&&
.MARINE...
232 AM CDT
AN ACTIVE WEATHER PATTERN IS LIKELY ACROSS THE LAKE OVER THE NEXT
COUPLE OF DAYS AS AN AREA OF LOW PRESSURE TRACKS FROM THE PLAINS
NORTHEASTWARD TOWARDS LAKE SUPERIOR BY MONDAY NIGHT. ULTIMATELY THIS
WILL RESULT IN A WARM FRONTAL BOUNDARY LIFTING NORTHWARD UP THE LAKE
TONIGHT THROUGH EARLY TUESDAY...FOLLOWED BY A COOL FRONTAL PASSAGE
ON TUESDAY. WINDS SOUTH OF THIS WARM FRONT WILL BECOME SOUTHERLY UP
AROUND 25 KT...WHILE NORTH OF THE WARM FRONT...SOME STOUT EASTERLY
WINDS WILL BE LIKELY. DUE TO THE PRESENCE OF HIGHER DEW POINT AIR
LIFTING OVER THE RELATIVELY COOLER WATER...AREAS OF FOG ARE ALSO
EXPECTED...ESPECIALLY IN THE VICINITY OF THE WARM FRONT. SOME PERIODS
OF DENSE FOG CANNOT BE RULED OUT TONIGHT INTO MONDAY. IN ADDITION TO
ALL THIS...THERE WILL ALSO BE A COUPLE PERIODS OF THUNDERSTORMS...LATER
TODAY THROUGH MONDAY. SOME OF THESE COULD PRODUCE STRONG WINDS AND
HAIL. ONCE THE COOL FRONT PASSES ON TUESDAY...CONDITIONS SHOULD
QUIET DOWN FOR A PERIOD.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...NONE.
&&
$$
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Area Forecast Discussion
National Weather Service Lincoln IL
1044 AM CDT Sun May 11 2014
.DISCUSSION...
ISSUED 1044 AM CDT Sun May 11 2014
Warm front continues to lift northward through the region this
morning. Boundary is becoming difficult to analyze, as winds have
become southerly across central Illinois, while the tightest dewpoint
gradient remains further south across central Missouri into far
southern Illinois. Cluster of convection is currently ongoing
north of the warm front over southwest Iowa. We will need to keep
a close eye on these storms as they track along the boundary
today. Some models develop this convection eastward into central
Illinois between 1 pm and 4 pm, while the HRRR continues to take
it more northeastward into northern Illinois, generally tracking
along the 850mb warm front. Since convective evolution remains
uncertain, will not be making any changes to the going forecast at
this time. POPs will be highest across the far N/NW KILX CWA in
closer proximity to the upper front and the potential track of the
Iowa convection. Further south into the warm sector, any storms
that fire south of the I-72 corridor will be much more scattered
in nature, so lower POPs are warranted there.
Barnes
&&
.AVIATION...
ISSUED 700 AM CDT Sun May 11 2014
A warm front lifting north across the area will stall out from
Galesburg to Champaign. Strong to severe storms will be possible
as early as 18-19z, but higher potential will occur as the
afternoon progresses. Timing of storms at each terminal site is
still uncertain, so VCTS was still left in this set of TAFs for
the afternoon into early evening. NCEP 4km WRF output has
scattered storms developing periodically across the area, so
multiple episodes of stormy weather could occur at any site. Any
periods of MVFR will be mainly during any thunderstorms and
primarily associated with visibility dropping during heavy rain.
Forecast soundings indicate cloud levels should remain VFR, even
during thunderstorms. However, brief MVFR conditions from cloud
levels will also be possible during any storms.
Winds will increase from the south by afternoon, with 15G28KT
possible in most areas. The northern terminals of PIA, BMI and CMI
will be closer to the front, so wind direction may be slightly
east of south and a little less gusty, but will still be breezy.
LLWS conditions are expected later tonight as an elevate low level
jet intensifies from SW to NE across the area. Wind direction
looks to be SW with wind speeds of 45kt in the 1200-1500 foot
level.
Shimon
&&
.PREV DISCUSSION...
ISSUED 330 AM CDT Sun May 11 2014
SHORT TERM...Today through Wednesday night
MCS with showers and scattered thunderstorms from I-72 south to
I-64 early this morning with isolated strong to severe storms
with hail and gusty winds of 40-60 mph moving east at 40 mph
toward the Wabash river. Models show these showers and
thunderstorms diminishing by sunrise as warm front lifts northward
across central and into northern IL during today. Kept a chance of
convection today and tonight though best chances northern areas.
SPC has slight chance of severe storms over most of CWA today and
early evening with moderate risk over central/southern IA into se
NE and north-central KS. SPC has slight risk of severe storms nw of
the IL river late Monday afternoon and Monday evening as cold
front approaches the MS river valley. Warmer highs in the 80s
today and Monday and more humid with dewpoints in the 60s.
Highest chances of convection will be Monday night western areas
and eastern IL Tue with passage of cold front. SPC has 5% risk of
severe storms Tue over far eastern IL with passage of cold front
though better chances further east over IN and lower MI.
Models continue to show surface low pressure ejecting ne from
southern MS river valley into the Ohio river valley Wed and qpf
moving back over central and especially eastern IL and have
increase pops on Wed and Wed evening. Large upper level trof
settles into the Midwest during mid week and have temps cooling
below normal by Wed/Thu with highs in the lower 60s and lows in
the 40s Wed night & Thu night.
LONG TERM...Thursday through Sunday
Extended models have been consistent in showing a large upper
level trof over the Great Lakes region and Midwest during mid/late week
and gradually pulls away from IL by Sunday. Below normal
temperatures expected during mid and late week with temps a good
10 degrees below normal. Instability isolated light showers
possible each day especially during the afternoon and early
evening hours until sunset due to upper level trof and a few
disturbances pivoting through the trof.
07
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
357 PM CDT SUN MAY 11 2014
.SYNOPSIS...
ISSUED AT 356 PM CDT SUN MAY 11 2014
12Z UA ANALYSIS HAS 850MB LOWS IN NORTHWEST MINNESOTA WITH A STRONG
850MB LOW IN WESTERN KANSAS. AN 850MB WARM FRONT RAN FROM THE KANSAS
LOW INTO SOUTHERN IOWA. A STRONG LLJ RAN FROM THE GULF COAST INTO
THE CENTRAL PLAINS. SATELLITE/RADAR TRENDS THROUGH MID AFTERNOON HAS
CONVECTION ACROSS EASTERN IOWA AND NORTHERN ILLINOIS WITH NEW
CONVECTION DEVELOPING IN THE PLAINS.
18Z SFC ANALYSIS HAS A WEAK LOW IN WESTERN WISCONSIN WITH A
DEVELOPING WARM FRONT SOUTHEAST INTO CENTRAL LAKE MICHIGAN. AN
IMPLIED LOW WAS IN SOUTHERN IOWA APPROACHING KOTM WITH ANOTHER LOW
IN WESTERN KANSAS. A FRONTAL BOUNDARY RAN FROM THE KANSAS LOW INTO
THE IOWA LOW NEAR KOTM WITH A WARM FRONT FROM NEAR KOTM NORTHEAST TO
THE WISCONSIN/ILLINOIS BORDER. DEW POINTS SOUTH OF THE FRONT WERE IN
THE 60S WITH 40S AND 50S IN THE NORTHERN PLAINS INTO THE GREAT LAKES
NORTH OF THE FRONT.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 356 PM CDT SUN MAY 11 2014
BOUNDARIES FROM THE NOCTURNAL THUNDERSTORM COMPLEX INITIATED A NEW
STORM COMPLEX ALONG THE WARM FRONT IN SOUTHERN IOWA THIS MORNING.
THIS NEW STORM COMPLEX MOVED EAST NORTHEAST AND IS SLOWLY DECAYING
ACROSS THE AREA.
HOWEVER...BOUNDARIES FROM THIS STORM ALONG WITH DIURNAL HEATING HAS
INITIATED NEW DISCRETE STRONG TO SEVERE STORMS THAT WILL CONTINUE
THROUGH LATE AFTERNOON.
BASED ON SATELLITE...RADAR...AND RAP TRENDS...THERE MAY BE A BREAK
IN STORM ACTIVITY THIS EVENING AS THE NEW SEVERE STORMS CONTINUE TO
DEVELOP AND MOVE NORTHEAST WELL WEST OF THE AREA.
AFTER MIDNIGHT THE STORMS OUT WEST WILL EVOLVE UPSCALE INTO ANOTHER
NOCTURNAL THUNDERSTORM COMPLEX THAT WILL SLOWLY MOVE INTO THE
NORTHWEST THIRD OF THE AREA. ISOLATED TO SCATTERED STORMS ARE VERY
POSSIBLE AHEAD OF THIS STORM COMPLEX AS MOISTURE CONTINUES TO FEED
INTO THE AREA.
ON MONDAY THE BETTER RAIN CHANCES WILL BE OVER THE NORTHWEST HALF OF
THE AREA DURING THE MORNING. DURING THE AFTERNOON...NEW CONVECTION
IS EXPECTED TO DEVELOP AS ANOTHER DISTURBANCE ALOFT MOVES THROUGH
THE AREA. BASED ON THE POSITION OF THE MAIN FEATURES AND OVERALL
EXPECTED FORCING...SEVERE STORMS ARE POSSIBLE.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 356 PM CDT SUN MAY 11 2014
MONDAY NIGHT THE MAIN COLD FRONT BEGINS MOVING THROUGH THE AREA.
CONVECTION IS EXPECTED TO BE WIDESPREAD AND MAY EVOLVE INTO A BAND
OF STRONG STORMS DURING THE EVENING HOURS. IF A BAND DOES FORM IT
WILL SLOWLY MOVE EAST OVERNIGHT.
ON TUESDAY...RAIN WILL END FROM WEST TO EAST DURING THE DAY WITH
MOST OF THE AREA BEING DRY BY MID DAY. TEMPERATURES WILL BE WELL
BELOW NORMAL.
HIGH PRESSURE MOVING THROUGH THE MIDWEST TUESDAY NIGHT WILL RESULT
IN DRY CONDITIONS WITH SEASONABLY COOL TEMPERATURES.
ON WEDNESDAY THE NEXT STORM SYSTEM MOVES NORTHEAST FROM THE SOUTHERN
PLAINS INTO THE OHIO VALLEY. THE TRENDS WITH THE MODELS HAVE BEEN TO
SLOWLY PULL THE STORM SYSTEM TO THE NORTH AND WEST.
WEDNESDAY NIGHT ON...
THERE CONTINUES TO BE DIFFERENCES BETWEEN THE GLOBAL MODELS AS TO
WHAT WILL OCCUR...BUT...ALL AGREE THAT TEMPERATURES WILL AVERAGE
BELOW NORMAL WEDNESDAY NIGHT THROUGH SUNDAY.
WEDNESDAY NIGHT/THURSDAY THE MODEL CONSENSUS HAS SLIGHT CHANCE TO
CHANCE POPS AS THE NEXT SYSTEM MOVES UP THROUGH THE OHIO VALLEY. THE
TREND IN THE MODELS HAS BEEN TO SLOWLY BRING THE STORM FURTHER TO
THE NORTH AND WEST.
THE MODEL CONSENSUS HAS MAINLY DRY CONDITIONS THURSDAY NIGHT AS THE
STORM SYSTEM EXITS THE AREA.
FRIDAY THROUGH SATURDAY THE MODEL CONSENSUS HAS MAINLY SLIGHT CHANCE
POPS FRIDAY AND SATURDAY WITH MAINLY DRY CONDITIONS FRIDAY NIGHT.
DISTURBANCES WILL CONTINUE TO ROTATE AROUND THE UPPER LOW OVER THE
GREAT LAKES PRODUCING MAINLY DIURNAL SHOWERS. IF ENOUGH CLEARING CAN
TAKE PLACE FRIDAY NIGHT AND WINDS REMAIN LIGHT...THERE MAY BE A
POTENTIAL FOR FROST.
DRY CONDITIONS SHOULD BE SEEN SATURDAY NIGHT AS HIGH PRESSURE MOVES
THROUGH THE AREA.
ON SUNDAY...THE MODEL CONSENSUS HAS SLIGHT CHANCE TO CHANCE POPS FOR
ROUGHLY THE WESTERN HALF OF THE AREA AS THE NEXT STORM SYSTEM MOVES
EAST FROM THE PLAINS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1210 PM CDT SUN MAY 11 2014
SHOWERS AND STORMS WILL PASS ACROSS THE TERMINALS THIS AFTERNOON
WITH PERIODS OF MVFR TO LOCAL IFR IN THE PRECIPITATION. THERE IS
A RISK OF SEVERE STORMS WITH LARGE HAIL AND DAMAGING WINDS MAINLY
SOUTH OF HWY 30. LOOKS LIKE A BREAK OR LULL IS EXPECTED FOR A TIME
THIS EVENING AS FOCUS FOR PRECIPITATION SHIFTS BACK WEST. SHOWERS AND
STORMS WILL LIKELY THEN MOVE BACK INTO PORTIONS OF THE AREA BY
LATE EVENING AND OVERNIGHT...MAINLY WEST OF THE MISSISSIPPI RIVER
DECAYING TO SHOWERS BY MID AM MONDAY. WINDS WILL BE GENERALLY
SOUTHERLY AROUND 10 KTS WITH OCCASIONAL GUSTS 20-25 KTS MAINLY
EAST CENTRAL AND SOUTHEAST IA.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
SYNOPSIS...08
SHORT TERM...08
LONG TERM...08
AVIATION...05
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1219 PM CDT SUN MAY 11 2014
.UPDATE...
ISSUED AT 1019 AM CDT SUN MAY 11 2014
CURRENT STORM COMPLEX OVER WESTERN IOWA IS SLOWLY DECAYING.
HOWEVER...BOUNDARIES FROM THIS COMPLEX ARE INTERACTING WITH THE
SURFACE WARM FRONT AND GENERATING NEW CONVECTION IN SOUTHWEST
IOWA THAT IS MOVING EAST NORTHEAST.
12Z UA ANALYSIS SHOWS A SHARP MOISTURE GRADIENT ACROSS THE AREA
WITH THE 850MB WARM FRONT ROUGHLY INTO SOUTHERN IOWA. STORMS IN
SOUTHWEST IOWA SHOULD GENERALLY MOVE ALONG SAID UPPER FRONT TOWARD
THE AREA THE REMAINDER OF THE MORNING.
NOWCASTING AND VARIOUS TOOLS/TECHNIQUES INDICATE VERY LITTLE IN
THE WAY OF FORCING ACROSS THE AREA THROUGH THE REMAINDER OF THE
MORNING. SHOWERS CANNOT BE RULED OUT DEVELOPING ALONG THE 850MB
WARM FRONT WITH POSSIBLY SOME THUNDER. RAP TRENDS INDICATE THE
850MB FLOW WEAKENING THROUGH MID DAY AND BEGINNING TO BACK WHICH
WOULD RE-FOCUS NEW DEVELOPMENT WEST OF THE AREA THIS AFTERNOON.
&&
.SYNOPSIS...
ISSUED AT 228 AM CDT SUN MAY 11 2014
00Z UPPER AIR ANALYSIS AND WV IMAGERY SHOWED STRONG SHORTWAVE
LIFTING EAST NORTHEAST INTO MINNESOTA WHILE ANOTHER WAVE WAS
ROUNDING THE BASE OF THE TROUGH OVER THE SOUTHWEST CONUS. GULF
MOISTURE FEED ALSO BEGINNING TO DEVELOP ACROSS THE SOUTHERN PLAINS
WITH 10C 85H DEWPOINTS AS FAR NORTH AS KANSAS CITY AT 00Z. AT THE
SURFACE...A FRONTAL BOUNDARY EXTENDED FROM NORTHWEST MISSOURI INTO
SOUTHERN ILLINOIS WITH CONVECTION MAINLY CONFINED ON THE COLD SIDE
OF THE BOUNDARY IN EASTERN MISSOURI AND SOUTHERN ILLINOIS. LATEST
RADAR IMAGERY SHOWED THE STORM CELL THAT DEVELOPED OVER IOWA
COUNTY AROUND MIDNIGHT HAS SINCE MOVED EAST AND DIMINISHED.
AT 2AM...TEMPERATURES WERE IN THE UPPER 50S TO LOWER 60S WITH
DEWPOINTS IN THE MIDDLE 40S TO UPPER 50S.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 228 AM CDT SUN MAY 11 2014
FORECAST FOCUS REMAINS ON SEVERE WEATHER POTENTIAL MAINLY THIS
AFTERNOON AND INTO THE OVERNIGHT HOURS.
TODAY...CONVECTION CURRENTLY DEVELOPING OVER SOUTHERN NEBRASKA
AND NORTHERN KANSAS TO LIFT EAST NORTHEAST AND BECOME MORE
WIDESPREAD OVER CENTRAL IOWA AS LLJ STRENGTHENS THIS MORNING AND
WHERE BETTER UPPER LEVEL DIVERGENCE WILL BE FOUND. LATEST HRR MODEL
TRENDS SHOW SCATTERED SHOWERS AND STORMS DEVELOPING MAINLY ACROSS
THE NORTHWEST THIRD OF THE CWA BY EARLY AFTERNOON. WARMING AROUND
925MB SHOULD HELP LIMIT ANY STORM DEVELOPMENT UNTIL THE AFTERNOON OVER
THE CWA. ANY STORM THAT DEVELOPS NORTH OF THE WARM FRONT COULD
BECOME SEVERE WITH MAIN THREATS LARGE HAIL AND DAMAGING WINDS.
DEEP MIXING AND STRONG WAA ALOFT WILL ALLOW FOR HIGHS UPPER 70S
NORTH TO THE MIDDLE 80S IN THE SOUTH BY THE AFTERNOON. INCREASING
DEWPOINTS INTO THE 60S WILL ALSO RESULT IN SOMEWHAT HUMID
CONDITIONS.
TONIGHT...WARM FRONT TO LIFT NORTH OUT OF THE CWA BY 00Z MONDAY. A
COLD FRONT WILL SLOWLY MAKE ITS WAY ACROSS IOWA. THERE IS A
POSSIBLY THAT THERE MAY BE SEVERAL HOURS LATE IN THE EVENING
WHERE THE REGION WILL BE DRY IN THE WARM SECTOR AND WILL PASS ON
THIS CONCERN TO THE NEXT SHIFT. AHEAD OF COLD FRONT MOVING OVER IOWA
...STRONG SOUTHERLY FLOW WILL CONTINUE TO USHER IN RICH GULF
MOISTURE WITH MODEL PWATS IN EXCESS OF 1.6 INCHES OVER CENTRAL
IOWA AND THE NORTHWEST SECTIONS OF THE CWA. EXPECT SUPERCELLS TO
FORM AHEAD OF FRONT OVER CENTRAL IOWA AND PROPAGATE EAST INTO THE
CWA EARLY MONDAY IN A VERY FAVORABLE ENVIRONMENT WITH SBCAPES IN
EXCESS OF 3000 J/KG AND 0-6KM SHEAR VALUES AROUND 40 KTS. MAIN
SEVERE THREATS AT THIS TIME WILL BE VERY LARGE HAIL AND DAMAGING
WINDS. LOCALLY HEAVY RAINFALL WILL ALSO BE POSSIBLE. ANOTHER VERY
MILD NIGHT IN STORE FOR THE REGION WITH LOWS ONLY IN THE MIDDLE
60S TO LOWER 70S.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 228 AM CDT SUN MAY 11 2014
EARLY MONDAY A DEEP UPPER TROF WILL BE LOCATED JUST EAST OF THE
ROCKIES WITH A SURFACE COLD FRONT FROM EASTERN MINNESOTA THROUGH
WESTERN IOWA. THE UPPER TROF AND COLD FRONT WILL MOVE SLOWLY EAST
MONDAY. THE COLD FRONT SHOULD MOVE THROUGH THE MID MISSISSIPPI
VALLEY FROM LATE MONDAY AFTERNOON THROUGH MONDAY EVENING. THE LATE
DAY AND EVENING TIMING OF THE COLD FRONTAL PASSAGE WILL FAVOR
ANOTHER RISK OF SEVERE THUNDERSTORMS FOR THE ENTIRE AREA SINCE THE
AIRMASS AHEAD OF THE FRONT WILL BE QUITE MOIST AND WILL HAVE PLENTY
OF TIME TO HEAT/DESTABILIZE PRIOR TO THE FROPA. HAVE HELD POPS IN
THE CHANCE CATEGORY MONDAY MORNING WITH LITTLE INDICATION OF
FORCING TO SUPPORT THUNDERSTORM DEVELOPMENT. CATEGORICAL POPS
WERE SPREAD EAST ACROSS THE AREA WITH THE BETTER FORCING
ASSOCIATED WITH THE COLD FRONT DURING THE AFTERNOON AND OVERNIGHT
HOURS. THE SEVERE THREAT SHOULD BE DURING THE AFTERNOON AND
EVENING AND CONSIST OF MAINLY LARGE HAIL AND DAMAGING WINDS. THERE
WILL BE LITTLE DIRECTIONAL SHEAR IN THE DEEP SOUTHERLY FLOW AHEAD
OF THE UPPER TROF TO SUPPORT A SIGNIFICANT TORNADIC THREAT. THE
SLOW MOVEMENT OF THE FRONT AND UPPER TROF ALONG WITH PW/S
EXCEEDING 1.5 INCHES WILL FAVOR QPF AMOUNTS OF AN INCH PLUS BY
TUESDAY MORNING NEAR AND EAST OF THE MISSISSIPPI RIVER.
THE LONGER RANGE MODELS ARE PRETTY CONSISTENT ON THE 00Z RUN OF
MOVING THE UPPER TROF INTO THE MISSISSIPPI VALLEY BY MID WEEK AND
CLOSING AN UPPER LOW OFF OVER THE NORTH CENTRAL STATES OR THE
WESTERN GREAT LAKES. THE UPPER LOW THEN LINGERS OVER THE AREA
THROUGH THE END OF THE WEEK. GIVEN THIS SCENARIO THE DEEP CYCLONIC
FLOW WITH THE UPPER LOW WILL KEEP SHOWERY AND COOL WEATHER OVER THE
REGION FOR THE REST OF THE WEEK. BY THURSDAY OR FRIDAY BOTH THE
ECMWF AND GFS SHOW A REINFORCING SHOT OF COOLER AIR MOVING SOUTH
INTO THE MID MISSISSIPPI VALLEY WITH H8 TEMPS AT OR JUST BELOW 0C
SPREADING OVER THE REGION. IF THIS VERIFIES AND THEN WE COULD SEE
LOWS TEMPERATURES IN THE MID TO UPPER 30S...OR COLDER GIVEN GOOD
RADIATIONAL COOLING CONDITIONS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1210 PM CDT SUN MAY 11 2014
SHOWERS AND STORMS WILL PASS ACROSS THE TERMINALS THIS AFTERNOON
WITH PERIODS OF MVFR TO LOCAL IFR IN THE PRECIPITATION. THERE IS
A RISK OF SEVERE STORMS WITH LARGE HAIL AND DAMAGING WINDS MAINLY
SOUTH OF HWY 30. LOOKS LIKE A BREAK OR LULL IS EXPECTED FOR A TIME
THIS EVENING AS FOCUS FOR PRECIPITATION SHIFTS BACK WEST. SHOWERS AND
STORMS WILL LIKELY THEN MOVE BACK INTO PORTIONS OF THE AREA BY
LATE EVENING AND OVERNIGHT...MAINLY WEST OF THE MISSISSIPPI RIVER
DECAYING TO SHOWERS BY MID AM MONDAY. WINDS WILL BE GENERALLY
SOUTHERLY AROUND 10 KTS WITH OCCASIONAL GUSTS 20-25 KTS MAINLY
EAST CENTRAL AND SOUTHEAST IA.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
UPDATE...08
SYNOPSIS...GROSS
SHORT TERM...GROSS
LONG TERM...DLF
AVIATION...05
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
257 PM CDT Sun May 11 2014
...Update to short term...
.SHORT TERM...(This evening through Monday)
ISSUED AT 254 PM CDT SUN MAY 11 2014
Abbreviated AFD due to ongoing warning operations.
From my mesoscale discussion at 1:53 PM...
(Convection already has developed by the same mesoscale assessments
still applies)
Special 18Z KDDC raob shows just a little bit of CIN remaining. Won`t
be long before convection develops. Visible satellite imagery shows
increasing cumulus along the dryline/front. HRRR indicates thunderstorms
developing along the Highway 283 corridor in the 3-4 pm time range.
Right moving Bunkers shows propagation vectors northeasterly at 45 kt.
Initial threat will be large hail (up to 20! on the LHP using NAM thermodynamic
and kinematic variables) and damaging outflow winds. There is an small
window of tornadic opportunity between 7 and 9 pm as low level winds
back across central/south central-Kansas but all the big wedge/strong tornadoes
should remain across Nebraska/Iowa with just small spin ups/weak tornadoes
in our area, if possible.
Convection will depart the area tonight. Some light showers will be
possible on the backside of the departing wave. It will be windy post
frontal through tomorrow. Right now conditions look borderline for wind
advisory criteria.
.LONG TERM...(Monday night through Sunday)
ISSUED AT 122 PM CDT SUN MAY 11 2014
An upper level longwave trough will be moving across the Plains on
Tuesday but should be dry with the moisture pushed east of the area.
Colder temperatures will accompany this trough with overnight lows
on Monday night into the mid 30s and highs on Tuesday in the low to
mid 60s. Strong northwest winds will mix down to the surface with
winds of 15 to 30 mph and partly cloudy skies.
For Wednesday into Thursday, dry northwesterly upper level flow will
follow with highs slowly warming into the upper 60s and 70s.
Wednesday morning may be the coldest morning with light winds and
lows in the low to mid 30s.
For Friday and Saturday, a few showers and thunderstorms may form as
as some upper air disturbances in northwest flow aloft interact with
increasing upslope moisture. Lows will be in the 40s and highs
around 70 to 75.
On Sunday, of next week, upper level ridging is forecast with dry
and warmer temps around 80.
&&
.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
ISSUED AT 1101 AM CDT SUN MAY 11 2014
VFR conditions through much of the TAF. Main exception is for KDDC/KHYS
this afternoon/eve, where convection could create temporary MVFR cigs in
heavy thunderstorm activity. Southerly winds 20-30 kt will become
northerly 15-28 kt in the wake of a fropa later tonight.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 46 56 35 63 / 20 10 0 0
GCK 42 53 34 62 / 20 20 0 0
EHA 42 55 34 61 / 10 10 0 10
LBL 44 58 34 62 / 10 10 0 10
HYS 46 53 35 63 / 80 30 0 0
P28 56 63 40 66 / 80 20 0 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY until 8 PM CDT this evening FOR KSZ046-065-066-
078>081-088>090.
RED FLAG WARNING until 9 PM CDT this evening FOR KSZ074>076-
084>086.
&&
$$
SHORT TERM...Sugden
LONG TERM...Kruse
AVIATION...Sugden
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
153 PM CDT Sun May 11 2014
...Update to mesoscale discussion...
.MESOSCALE DISCUSSION...
ISSUED AT 153 PM CDT SUN MAY 11 2014
Special 18Z KDDC raob shows just a little bit of CIN remaining. Won`t
be long before convection develops. Visible satellite imagery shows
increasing cumulus along the dryline/front. HRRR indicates thunderstorms
developing along the Highway 283 corridor in the 3-4 pm time range.
Right moving Bunkers shows propagation vectors northeasterly at 45 kt.
Initial threat will be large hail (up to 20! on the LHP using NAM thermodynamic
and kinematic variables) and damaging outflow winds. There is an small
window of tornadic opportunity between 7 and 9 pm as low level winds
back across central/south central-Kansas but all the big wedge/strong tornadoes
should remain across Nebraska/Iowa with just small spin ups/weak tornadoes
in our area, if possible.
&&
.SHORT TERM...(Today and tonight)
ISSUED AT 200 AM CDT SUN MAY 11 2014
Thunderstorms are likely across central and eastern portions of
southwest Kansas today as an upper level trough digs further
southeast into the Four Corners Region. As the upper level system
approaches, short range models indicate an upper level jet
intensifying as it lifts out of the trough axis northeast across the
Western High Plains. Meanwhile, deep low level moisture will
continue to lift northward into south central and eastern portions
of southwest Kansas ahead of a sharpening dryline this afternoon.
While dynamic support becomes increasingly favorable during the
afternoon, thunderstorms are expected to develop along and ahead of
a cold front as it surges southeastward through western Kansas,
slamming into the dryline while capping continues to erode. Based
on NAM/GFS model soundings, the potential for severe weather exists
with steep lapse rates developing and SBCAPE values in excess of
2500 J/KG ahead of the dryline. Ample deep layer shear and favorable
low level shear will support increased tornado potential across
central and possibly south central Kansas toward Sunday evening.
Otherwise, golf ball to tennis ball size hail and damaging winds in
excess of 60 mph will be possible with any storm that becomes severe.
Strong southerly winds are expected to develop across central and
portions of southwest Kansas this afternoon as surface low pressure
deepens across extreme southwest Kansas and the panhandles of
Oklahoma and Texas. This will create a tight pressure gradient
across the aforementioned area resulting in stronger southerly
winds. Additionally, the NAM and GFS show H85 winds of 40 to 50kt
setting up here as well. As the cap erodes this afternoon, these
winds are expected to mix down to the surface enhancing wind
strength. Therefore, a wind advisory will be issued for the affected
area this afternoon/evening.
The warming trend continues today as surface low pressure lee of the
Rockies strengthens increasing a strong southerly flow into central
and southwest Kansas. This will draw warmer air into central and
southwest Kansas ahead of an approaching cold front. The NAM/GFS
show H85 temperatures ranging from the mid to upper 20s(C) across
the area. Considering the cold front is not expected move in until
mid to late afternoon, highs are likely to reach the upper 80s(F) to
the lower 90s(F) in across central and much of southwest Kansas this
afternoon. Look for lows down into the 40s(F) across west central
Kansas to the 50s(F) in south central Kansas tonight.
.LONG TERM...(Monday night through Sunday)
ISSUED AT 122 PM CDT SUN MAY 11 2014
An upper level longwave trough will be moving across the Plains on
Tuesday but should be dry with the moisture pushed east of the area.
Colder temperatures will accompany this trough with overnight lows
on Monday night into the mid 30s and highs on Tuesday in the low to
mid 60s. Strong northwest winds will mix down to the surface with
winds of 15 to 30 mph and partly cloudy skies.
For Wednesday into Thursday, dry northwesterly upper level flow will
follow with highs slowly warming into the upper 60s and 70s.
Wednesday morning may be the coldest morning with light winds and
lows in the low to mid 30s.
For Friday and Saturday, a few showers and thunderstorms may form as
as some upper air disturbances in northwest flow aloft interact with
increasing upslope moisture. Lows will be in the 40s and highs
around 70 to 75.
On Sunday, of next week, upper level ridging is forecast with dry
and warmer temps around 80.
&&
.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
ISSUED AT 1101 AM CDT SUN MAY 11 2014
VFR conditions through much of the TAF. Main exception is for KDDC/KHYS
this afternoon/eve, where convection could create temporary MVFR cigs in
heavy thunderstorm activity. Southerly winds 20-30 kt will become
northerly 15-28 kt in the wake of a fropa later tonight.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 45 55 35 63 / 30 10 0 0
GCK 43 52 34 62 / 20 20 0 0
EHA 43 54 34 61 / 10 10 0 10
LBL 45 56 34 62 / 10 10 0 10
HYS 45 54 35 63 / 60 30 0 0
P28 52 62 40 66 / 80 10 0 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY until 8 PM CDT this evening FOR KSZ046-065-066-
078>081-088>090.
RED FLAG WARNING until 9 PM CDT this evening FOR KSZ074>076-
084>086.
&&
$$
MESOSCALE...Sugden
SHORT TERM...JJohnson
LONG TERM...Kruse
AVIATION...Sugden
AREA FORECAST DISCUSSION
NWS PADUCAH KY
418 PM CDT Sun May 11 2014
.SHORT TERM...(Tonight through Tuesday night)
Issued at 317 PM CDT SUN MAY 11 2014
Pockets of surface-based instability continue to expand over the
WFO PAH CWA this afternoon, aided by decent insolation and weak to
moderate directional shear (25-35 knots) aloft (as evidenced by
the anvil rain plumes oriented from northwest to southeast). The
old cold pool has eroded over southeast IL and southwest IN from
the morning convection, so distinct theta-e gradients are in
place. Given the GOES Water Vapor imagery, the moisture gradient
aloft implies a gradient in lapse rates as well, helping to
enhance updrafts. (This is evidenced by the newly organized storms
with hail in Southeast IL).
The 12km RUC also suggests that the expended CAPE along and north
of the implied surface warm frontal reflection arcing from
northwest to southeast through southeast Illinois into northwest
Kentucky. Further expenditure of CAPE through 01z suggests that
the pool of convective instability should drop markedly. In
addition, model heights are expected to rise this evening with a
subtle change in balance takes place between the eastern U.S. ridge
and the center of the sharpening trough over Western Nebraska.
Expect that rain chances will be essentially nil over the entire
WFO PAH CWA by midnight, as the warm frontal boundary moves well
north of the area and shear decreases with time.
As mentioned in yesterday`s discussion, channeled vorticity along
the eastern limb of the trough near the inflection point between
the trough/ridge circulation (cyclonic/anticyclonic flow) will aid
in creating some lift in advance of an approaching moisture plume
from the Gulf of Mexico around daybreak on Monday. This transition
zone for convection will move slowly east through Monday
afternoon, as the main trough actually sharpens and becomes
slightly negatively tilted west of Iowa and Missouri Monday night
into Tuesday morning.
By 09z (4 am CDT) Tuesday morning, the cold front associated with
this trough is expected to move into western sections of the WFO
PAH Forecast area (Southwest IL/Southeast MO). By late evening
Monday and into early Tuesday, the coverage of showers and
thunderstorms should pick up significantly. It is at this time,
that my concern for heavy rain potential will increase, with the
potential for at least minor flooding by daybreak on Tuesday over
parts of Southeast Missouri northeast to the Mississippi River.
QPF values in excess of two inches would not be out of the
question during that time period.
The 12km NAM-WRF is actually suggesting a new closed circulation
will develop at the based of the mean trough over the upper
Midwest, somewhere near the OK/TX panhandles by Tuesday night,
moving into southern Missouri by Wednesday evening. This is similar to
what the ECMWF advertised in the Friday/Saturday model runs. This
will lead to enhanced precipitation, both pre/post frontal as the
frontal boundary remains fixed along the Interstate 57/55 corridor
in Southern IL/Southeast Missouri. Most of the upright
(thunderstorm) instability may be mixed out by Tuesday afternoon
and night, but warm top (satellite reference) convection processes
will likely take over increasing the effectiveness of the
rainfall from Tuesday into Wednesday. There is still some question
with respect to severe potential during this time period, but
heavy rainfall still remains the dominant threat Tuesday into
Wednesday.
.LONG TERM...(Wednesday through Sunday)
Issued at 417 PM CDT SUN MAY 11 2014
Confidence is fairly high concerning the general synoptic pattern in
the Wed-Sun time frame. It is looking more and more like a high
amplitude mid level trof will be carved out from southeast Canada
southward all the way into the Ms River Valley by the Wed/Thu
period. On east side of the trof, broad swly flow aloft will be
evident. As a sfc low lifts ne along the spine of the Appalachians
Wed, it appears showers will once again overspread most of the
forecast area. Highest rain amounts will probably be over wrn KY and
sw IN. Once the sfc low pulls off to the northeast Wed night, and
the h50 trof axis moves east of the region, rain chcs should
decrease considerably for much of the remainder of the extended.
However, very low height fields and extensive daytime cloudiness
behind the system will likely lead to an extended period of below
normal temperatures. Highs are only expected to reach the 60s most
locations Thu/Fri/Sat.
&&
.AVIATION...
Issued at 1258 PM CDT SUN MAY 11 2014
Expect generally VFR conditions through the TAF period. Hit and
miss thunderstorms will need to be monitored through the afternoon
for brief IFR restrictions, but coverage is just not high enough
to mention explicitly in the TAF package at this time.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...LAKE WIND ADVISORY until 7 PM CDT this evening FOR ILZ080-084-
088-092.
MO...LAKE WIND ADVISORY until 7 PM CDT this evening FOR MOZ076-086-
087-100-107>111-114.
IN...NONE.
KY...NONE.
&&
$$
SHORT TERM...Smith
LONG TERM...GM
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1239 PM CDT Sun May 11 2014
.MESOSCALE DISCUSSION...
Issued at 1238 PM CDT SUN MAY 11 2014
This interim (midday) update was a little challenging given the
impact of the early morning showers and thunderstorms that
transited across the north part of the WFO CWA. The more organized
cluster of multicell storms set up a fairly robust outflow
boundary region this morning. Even with the expectation that this
complex would develop overnight and into this morning, the degree
of cold pool generation was more impressive than expected.
In addition, there is a slight veering of winds between 7-17kft
per the KPAH VAD Wind Profile to support a little enhanced shear
for updrafts. This may be enough to maintain isolated to widely
scattered clusters of multicell thunderstorms into the afternoon,
given cold pool interactions among developing cells and
established thunderstorms.
The 3km HRRR and 12km NAM-WRF have picked up on the interaction of
this cold pool and the attendant theta-e convergence south of the
boundary (per hourly LAPS instability fields). With this in mind,
a greater coverage of thunderstorms had to be considered for this
afternoon than previously forecast.
Associated adjustment to temperature, dewpoint, winds, and sky
cover were made to reflect the change in thunderstorm activity
this afternoon.
Depending on the coverage of shower and thunderstorm activity,
there is still some uncertainty as to the degree of severe
potential this afternoon and the potential interaction with the
IA/MO MCS. Will have to take a "wait and see" position on this matter.
The current Lake Wind Advisory still looks to be good call for
this afternoon.
&&
.SHORT TERM...(Today through Tuesday night)
Issued at 304 AM CDT SUN MAY 11 2014
Scattered thunderstorms moving eastward across the far northern
sections of our CWA at the time of this writing should continue to
shift eastward and weaken with time (by sunrise).
Beyond that there will probably be a lull in convective activity
this morning, but this afternoon isolated thunderstorms are possible
just about anywhere in the heat of the day. Coverage may become a
bit more widespread in the vicinity of any outflow boundaries laid
down by the overnight convection, but would be too difficult to pin
down, so consequently just went with a 15 POP everywhere and just
mentioned isolated thunderstorms.
As a storm system begins to move out of the plains tonight, it will
turn the flow aloft back to southwest thereby pumping the H5 ridge
up a bit over our area. Combined with no low level forcing and being
in the warm sector, expect it to be dry. Precipitation chances make
their way back into the forecast on Monday as the aforementioned
system moves ever closer to our area. Precipitation chances will be
highest Monday night and Tuesday as the system actually crosses the
area.
There is some disparity between models on how things are going to
evolve Tuesday night. All models show the approach of a sharp short
wave with southwest flow aloft parallel to the departing frontal
boundary, yet the GFS pushes the boundary through the area with
decreasing precipitation chances from west to east. The NAM12, SREF,
and GEM are all showing a wave being induced on the front as a
result of the approaching short wave thus producing an overrunning
scenario which produces decent precipitation chances back across the
entire CWA. Given the synoptic parameters, I tend to believe the
solution of the majority, so increased POPs accordingly.
.LONG TERM...(Wednesday through Saturday)
Issued at 304 AM CDT SUN MAY 11 2014
Rain shower chances will linger through much of the week as a deep
longwave trough slowly trudges east across the nation. Rain is not
expected all the time, but until the mean trough axis finally clears
the region, the chance for rain will be present each day.
Starting with 12Z Wednesday, the axis of the 500mb trough will be
positioned from low pressure over Ontario south across the Upper
Midwest into the Missouri Valley and Southern Plains. A cold front
will be positioned just east of the forecast area. Models are still
not in complete agreement on the synoptic setup during the mid to
late week, with the GFS still a notable outlier compared with the
ECMWF and GEM. We continue to favor the slower majority solution at
this time.
Consequently, Wednesday is looking rather soggy as a piece of
southern stream energy ejects northeast from the base of the upper
level trough. Will carry likely precipitation probabilities across
the entire region on Wednesday. Any elevated instability will be
limited to southwest Indiana and the Pennyrile region of western
Kentucky, so introduced a slight chance thunder mention there.
It appears as though the better rain chances will shift east of the
area by Wednesday night and Thursday. However, with the upper level
trough still positioned directly overhead, scattered rain showers
still cannot be ruled out, especially from late morning through
early evening each day. Even once the trough axis moves just to our
east, energy rotating around the back side of the trough makes the
return to dry weather less certain late in the week. Limited
instability should keep any thunder to a minimum during this time.
Much more certain is the drop in temperatures in the wake of the
Tuesday cold frontal passage. Highs through the remainder of the
week should only reach the 60s, with lows between 45 and 50.
&&
.AVIATION...
Issued at 304 AM CDT SUN MAY 11 2014
A complex of thunderstorms over the St Louis Metro area at this
time will most likely progress east or east southeast overnight,
and may clip KEVV on the way by. Also would not be surprised to
see a portion of the complex split off and propagate slowly
southward, potentially impacting KCGI or KPAH by morning. Will
monitor for possible inclusion of TS in the forecast, but
confidence at this time is too low to insert as prevailing or even
a TEMPO condition.
Some increase in lower clouds is expected toward morning, but they
should be at or above 3kft. Forecast sounding data indicate that
diurnal convection is a good possibility throughout the area
Sunday. Decided to mention TS in a PROB30 at all sites through the
afternoon. Otherwise some gusty south winds are likely from mid-
morning through the afternoon at all sites.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...LAKE WIND ADVISORY until 7 PM CDT this evening FOR ILZ080-084-
088-092.
MO...LAKE WIND ADVISORY until 7 PM CDT this evening FOR MOZ076-086-
087-100-107>111-114.
IN...NONE.
KY...NONE.
&&
$$
MESOSCALE...Smith
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1248 PM EDT Sun May 11 2014
...Updated Aviation Discussion...
...Forecast Update...
Issued at 1140 AM EDT Sun May 11 2014
A few storms are moving back into southern Indiana late this
morning. Taking a look at models this morning, most of them seem to
be overdoing convection for the morning hours, which makes this
afternoon`s forecast all the more difficult. The HRRR seems to have
the best handle on the current situation, though it is not great
either. Still think the best chance for storms will be west of I-65.
However, cannot rule out isolated storms across east central
Kentucky, so added low pops to this area for the afternoon. The rest
of the forecast remains unchanged.
Issued at 930 AM EDT Sun May 11 2014
The convection from the MCS across southern Indiana this morning
continues to move east. Went ahead and removed pops for the
remainder of the morning hours. A couple of outflow boundaries from
this convection have set up across southern Indiana and central
Kentucky. These may serve as a focus for some strong storms this
afternoon, particularly across southern Indiana which will be closer
to an upper level disturbance. Also removed the fog wording from the
forecast as fog that developed this morning has mixed out.
.SHORT TERM (Now through Monday)...
Issued at 325 AM EDT Sun May 11 2014
The synoptic pattern early this morning features a strong
upper-level trough diving into the southwestern CONUS. In response,
the upper-level flow has begun to amplify a ridge over the Ohio
Valley. This amplification will continue through the short-term
period, leading to much warmer temperatures.
An MCS continue to progress across portions of central Illinois and
western Indiana this morning. This activity is located along the
LLJ axis, which extends from Missouri northeast into IL and IN.
Current trends suggest this activity will remain mostly north of the
region, but could clip our southern IN counties in the pre-dawn
hours. Therefore, will raise pops a bit to account for this
activity.
Otherwise, the MCS will quickly dissipate this morning, leaving
partly to mostly cloudy skies in it`s wake. As thicknesses rise, we
should see temperatures climb well into the 80s today. There is a
consistent signal in both synoptic and hi-res guidance that some
isolated to widely scattered thunderstorms will develop this
afternoon into early this evening, mainly along and west of I-65.
Here, low-level moisture will increase which coupled with
temperatures in the 80s, will yield MLCAPE on the order of 1500-2500
J/kg. As opposed to yesterday, forcing looks rather benign, with no
significant surface future for convection to focus on (although an
outflow boundary from this morning`s MCS could set up across the
region so this will have to be monitored today for a possible
convective focus). As a wave of isentropic ascent spreads northeast
across the region, the lift may be enough to pop some convection
within an uncapped atmosphere. Given the degree of instability,
some isolated stronger storms with small hail and gusty winds will
be possible, but the lack of any significant, convergent surface
feature or upper-level support should help to limit storm
organization.
Any convection this evening will quickly dissipate with the loss of
daytime heating, leading to a dry night. Winds should stay up a bit
as high-level clouds stream by. Thus, think temperatures will stay
up a bit in the mid to upper 60s.
Monday looks quite similar to today. Instability will once again
build in the afternoon, but any forcing will be subtle and
incoherent. Therefore, will continue with just slight chance of
thunderstorms in the afternoon hours, but most will stay dry. Highs
may be a degree warmer than today as the upper-level ridge takes
hold, with highs in the middle to even upper 80s.
.LONG TERM (Monday Night through Saturday)...
Issued at 330 AM EDT Sun May 11 2014
The long term guidance continues to show an active pattern across
North America through the upcoming long term period as a significant
upper level trough axis moves through the Plains states and then
develops into a large upper level gyre over the Great Lakes by the
late part of the work week. A strong cold front associated with the
upper level wave is forecast to push through the region around
midweek bringing a good amount of precipitation to the region along
with a threat of thunderstorms. In the post frontal wake, it
appears that scattered to numerous diurnally driven rain showers
will continue into the latter half of the week along with colder
than normal temperatures. Current data still suggests that we`ll
see temperatures drop to 10 to perhaps as much as 20 degrees below
seasonal normals by late week and into next weekend.
Monday night through Wednesday Night...
Latest model guidance continues to show better forecast convergence
in this time frame with the frontal boundary coming through the
region. It appears that ridging will hold on for Monday night into
most of Tuesday. In fact, Tuesday could be a bit drier and warmer
as the front approaches from the west. Lows Monday night will be
mild with readings generally in the middle to upper 60s. Tuesday is
a bit of a question mark which will depend on clouds and
precipitation in the pre-frontal airmass. The Euro and Canadian GEM
guidance are very bullish on temperatures for Tuesday with highs
climbing into the middle to upper 80s. We are a bit hesitant to
jump on temperatures that quickly, but the multi-model consensus has
trended warmer, so we have raised temperatures into the middle 80s
for much of the region.
Scattered showers and storms will likely develop to our west along
the frontal boundary and push into the region Tuesday afternoon and
evening. The front will slow down a bit and stall slightly on
Wednesday across our region. A strong mid-level vorticity lobe will
advance through the upper trough and likely result in a secondary
area of low pressure which would ride up along the frontal
boundary. This feature would end up producing widespread clouds
and precipitation for the Wednesday and Wednesday night time frame.
For now, have kept much of the forecast trends intact here with the
high probabilities of precipitation from Tuesday evening through
Wednesday evening. Thunderstorms will accompany the front as it
pushes through Tuesday afternoon/evening. However, main dynamical
forcing will be well to the north of our region. Slab forced ascent
combined with abundant height falls aloft should result in adequate
lift for convection. Heavy rainfall, lightning, and gusty winds
appear to be the main threats at this time.
Temperatures Tuesday night will cool into the upper 50s to the lower
60s with highs on Wednesday warming into the mid-upper 60s in the
west and upper 60s to lower 70s in the east. Distinctly cooler
weather will arrive Wednesday night as temperatures fall into the
upper 40s behind the frontal boundary.
Thursday through Saturday...
Surface frontal boundary is expected to be to the east of the region
by Thursday morning with the upper trough axis lagging behind. The
upper trough axis looks to pass over the region Thursday afternoon
and evening which will likely produce scattered rain showers. The
rain chances will likely diminish in areal coverage by
Friday...except perhaps across our northeastern counties where
isolated showers may persist into the day on Friday. The
aforementioned frontal boundary looks to stall out across the deep
south by late Friday into Saturday with several disturbances moving
through the upper trough which will remain across the eastern US.
These disturbances may continue to produce cloudiness along with
isolated showers...especially during the afternoon hours. The
larger weather story of the period will the drop in temperatures
compared to what we have seen of late. The cool northwest flow will
keep temperatures some 10 to as much as 20 degrees below seasonal
normals. Highs Thursday through Saturday will only warm into the
lower 60s in the north with lower to middle 60s across the south.
Overnight lows will generally be in the lower to middle 40s.
Generally stuck close to the Euro bias-corrected temperature
profiles for the this time frame given their exceptional
verification over the last 5-7 days in this forecast time frame.
&&
.AVIATION (18Z TAF Update)...
Issued at 145 PM EDT Sun May 11 2014
A cu field is increasing across the area this afternoon as
instability increases. Some storms have developed across southern IN
and western KY and will spread eastward through the afternoon. The
best chance for thunderstorms this afternoon will be at SDF and BWG
from around 20-00Z. Will continue the mention of VCTS for these
terminals and monitor for amendments when storms do develop. There
is an isolated chance for storms to develop at LEX. However,
coverage is expected to be less across east central KY, so will
leave mention out of the TAF for now. Winds will be out of the south
and increase to around 10 knots this afternoon. For tonight some
light fog may be possible, mainly at BWG where winds look to be a
bit lighter.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
KY...NONE.
IN...NONE.
&&
$$
Update.........EER
Short Term.....KJD
Long Term......MJ
Aviation.......EER
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
1203 PM CDT SUN MAY 11 2014
.AVIATION...
GENERAL VFR CONDITIONS ARE EXPECTED OUTSIDE CONVECTIVE IMPACTS.
AREA UNDER A VERY UNSTABLE AIR MASS WHERE COVERAGE MAY BECOME
ROBUST FOR AN HOUR OR TWO BETWEEN 18Z-22Z BEFORE THINNING OUT.
CONVECTIVE GUST POTENTIAL APPEARS TO BE IN THE 30-35 KT RANGE FROM
DOWN BURSTS BUT ALL ACTIVITY IS IMPLANTED ON DEEP LAYERED
SOUTHEASTERLY FLOW FOR CELL MOVEMENTS 15-20 KT TO THE NNW. SOME
MVFR CIGS/VSBY POSSIBLE OVERNIGHT FROM RESIDUAL MOISTURE AFTER
BOUNDARY LAYER DECOUPLES...THEN IMPROVING TO VFR BASES 030-040
MAINLY AFTER 15Z MONDAY. 24/RR
&&
.PREV DISCUSSION... /ISSUED 927 AM CDT SUN MAY 11 2014/
SOUNDING DISCUSSION...
12Z SOUNDING WAS NOT QUITE AS MOIST AS PREVIOUS WITH THE PRECIP
WATER AT 1.57 INCHES...DOWN FROM 1.85 INCHES. INSTABILITY HAD
INCREASED HOWEVER WITH THE MUCAPE AT 2321 J/KG AND LI -5. ELEVATED
CAP/INVERSION WAS AROUND 550 MB...BUT THIS WILL BE TOO HIGH UP TO
BE AN INHIBITOR FOR DEEP CONVECTION TODAY ONCE TEMPERATURES REACH
THE LOWER 80S. WIND PROFILE FROM SURFACE TO 700 MB WAS SOUTHERLY
15 TO 25 KNOTS WHICH WILL BE FAVORABLE FOR TRANSPORTING DEEPER LOW
LEVEL MOISTURE AND HIGHER PRECIP WATER VALUES BACK INTO THE
FORECAST AREA BY EARLY AFTERNOON AS INDICATED BY THE MODELS. THIS
LOOKS SUPPORTIVE OF THE CURRENT FORECAST PROBABILITY OF 40 PERCENT
FOR SHOWERS AND THUNDERSTORMS. ABOVE 700 MB...WINDS BECOME LIGHT
AND VARIABLE FROM 650 MB TO AROUND 400 MB...AND THIS KNOCKS THE
0-6 KM STORM MOTION DOWN TO 195 DEGREES AT 9 KNOTS. WESTERLY WINDS
INCREASE QUITE A BIT ABOVE 300 MB PEAKING NEAR 85 KNOTS NEAR 150
MB/ 45 KFT. 22/TD
PREV DISCUSSION... /ISSUED 355 AM CDT SUN MAY 11 2014/
DISCUSSION...
GENERALLY ONLY MINOR CHANGES MADE TO THE FORECAST WITH THIS
PACKAGE AS FORECAST REASONING HASN/T CHANGED AND MODELS ARE
COMING INTO BETTER AGREEMENT CONCERNING THE MID WEEK COLD FRONT.
MUGGY CONDITIONS WILL STICK AROUND THROUGH MID WEEK AS ONSHORE
WINDS CONTINUE TO RESULT IN AN INFLUX OF WARM AND MOIST AIR INTO
THE REGION FROM THE GULF OF MEXICO. THIS WILL KEEP TEMPERATURES...
ESPECIALLY OVERNIGHT...ABOVE NORMAL. AFTERNOON TEMPERATURES
GENERALLY FORECAST TO TOP OUT IN THE MID TO UPPER 80S WITH
OVERNIGHT LOWS STRUGGLING TO DROP BELOW 70 DEGREES.
EXPECT DIURNALLY FORCED CONVECTION EACH AFTERNOON WITH GENERALLY
ISOLATED TO WIDELY SCATTERED COVERAGE. LATEST MODEL RUNS...BOTH
SYNOPTIC AND MESOSCALE...ARE A BIT MORE AGGRESSIVE DEVELOPING
CONVECTION TODAY SO HAVE BUMPED POPS UP TO SOLID CHANCE...AROUND
40 PERCENT...FOR MOST OF THE AREA. LATEST HRRR AND NCEP WRF RUNS
INDICATE SOME CONVECTION DEVELOPING OVER THE NORTHERN GULF BY 14Z
OR 15Z AND THEN MOVING OR SPREADING INLAND BY EARLY AFTERNOON. ON
AVERAGE...QPF SHOULD BE LESS THAN A QUARTER INCH...BUT A FEW
PLACES COULD SEE UP TO AN INCH OF RAIN TODAY IF IMPACTED BY A
HEAVIER STORM OR TWO. SIMILAR CONDITIONS EXPECTED MONDAY...
THOUGH COVERAGE SHOULD BE SLIGHTLY LESS. AM CARRYING 20 TO 30
PERCENT POPS ACROSS THE AREA MONDAY AFTERNOON.
BY TUESDAY...STRONG UPPER TROUGH WILL BE DIGGING INTO THE PLAINS
STATES AND FORCING A COLD FRONT TOWARD THE NORTHERN GULF COAST
REGION. MODELS HAVE COME INTO MUCH BETTER AGREEMENT CONCERNING
BOTH THE AMPLITUDE OF THIS TROUGH AND THE TIMING OF THE SURFACE
COLD FRONT. LOOKS LIKE THE SURFACE FRONT SHOULD PASS THROUGH THE
AREA SOME TIME LATE TUESDAY NIGHT OR EARLY WEDNESDAY MORNING...
WITH COOLER AND DRIER AIR FILTERING INTO THE AREA DURING THE DAY
WEDNESDAY. EXPECT A FAIRLY SIGNIFICANT TEMPERATURE DROP BEHIND THE
FRONT WITH AFTERNOON HIGHS ON WEDNESDAY CURRENTLY FORECAST TO BE
5 TO 10 DEGREES LOWER THAN HIGHS ON TUESDAY. THE REAL DIFFERENCE
WILL BE FELT AT NIGHT...THOUGH...WITH OVERNIGHT LOWS PLUNGING INTO
THE 50S WEDNESDAY NIGHT THROUGH FRIDAY NIGHT FOR MOST OF THE AREA.
NORTHWEST FLOW ALOFT WILL PREVAIL THROUGH THE REMAINDER OF THE
FORECAST PERIOD. MODELS CURRENTLY HINTING AT ANOTHER DISTURBANCE
MOVING INTO THE SOUTHEAST CONUS OVER THE WEEKEND...THOUGH BOTH THE
EURO AND GFS KEEP THE MOISTURE AND FORCING TO THE NORTHEAST OF THE
LOCAL AREA. WITH THIS IN MIND...AM KEEPING A DRY FORECAST THROUGH
THE WEEKEND AT THIS TIME.
AVIATION...
VARIABLE CONDITIONS WERE BEING OBSERVED EARLY THIS MORNING ACROSS
THE FORECAST AREA...RANGING FROM VFR TO LIFR DUE TO CEILINGS BEING
OBSERVED AT SOME OF THE TAF SITES. SOME GENERALLY LIGHT FOG WAS ALSO
IMPACTING A NUMBER OF THE TERMINALS. CONDITIONS ARE EXPECTED TO
IMPROVE TO VFR AT ALL LOCATIONS BY LATE MORNING OR EARLY AFTERNOON.
SCATTERED CONVECTION THIS AFTERNOON WILL BE POSSIBLE AT EACH OF THE
SITES. MVFR TO IFR CEILINGS WILL AGAIN BE POSSIBLE LATE TONIGHT AND
EARLY MONDAY MORNING.
MARINE...
MODERATE SOUTHEAST FLOW WILL CONTINUE ACROSS THE COASTAL WATERS
TODAY AND MONDAY BEFORE EASING ON TUESDAY. A COLD FRONT WILL PUSH
ACROSS THE COASTAL WATERS LATE TUESDAY NIGHT INTO WEDNESDAY WITH
STRONG OFFSHORE FLOW DEVELOPING IN ITS WAKE FROM LATE WEDNESDAY INTO
THURSDAY.
DECISION SUPPORT...
DSS CODE...BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...SLURRY SUPPORT
MONITORING RIVER FLOODING
DECISION SUPPORT SERVICES (DSS) CODE LEGEND
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION
BLUE = LONG FUSED WATCH/WARNING/ADVISORY IN EFFECT OR HIGH
VISIBILITY EVENT
YELLOW = HEIGHTENED IMPACTS WITH SHORT FUSED
WATCH/WARNING/ADVISORY ISSUANCES; RADAR SUPPORT
ORANGE = HIGH IMPACTS - SLIGHT TO MODERATE RISK SEVERE; NEARBY
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED = FULL ENGAGEMENT FOR MODERATE TO HIGH RISK SVR
AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL
SIGNIFICANCE
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 85 67 86 67 / 40 20 30 20
BTR 86 72 87 70 / 40 20 30 20
ASD 83 71 83 70 / 40 30 20 20
MSY 85 73 83 71 / 40 20 20 20
GPT 84 74 84 72 / 40 20 20 20
PQL 83 69 85 70 / 40 20 20 20
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
643 PM EDT SUN MAY 11 2014
.SYNOPSIS...
ALTHOUGH WARM WEATHER WILL QUICKLY RETURN...THE CHANCE FOR RAIN
INCREASES AS THE WEEK PROGRESSES.
&&
.NEAR TERM /THROUGH MONDAY/...
ONLY MADE A SLIGHT UPDATE TO ADJUST POPS THROUGH THE NEXT SEVERAL
HOURS BASED ON RECENT SATELLITE DATA AND RADAR TRENDS AS SOME
SHOWERS HAVE POPPED UP IN OHIO. THE HI RES MODELS CONTINUE TO
INDICATE THAT FURTHER DEVELOPMENT COULD OCCUR IN OHIO
TONIGHT...WITH THE HRRR BRINGING A SECOND WAVE OVER THE NORTHERN
COUNTIES TOWARDS MORNING. AS OF NOW HOWEVER...THE MESOANALYSIS
SHOWS THAT MUCH OF THE REGION REMAINS CAPPED. WILL MAINTAIN CHANCE
POPS THROUGH THE OVERNIGHT WITH ADVANCING WARM FRONT.
OTHERWISE FORECAST REMAINS ON TRACK.
PREVIOUS DISCUSSION FOLLOWS...
PRECIP CHANCES WILL CONTINUE THROUGH THE DAY ON
MONDAY...INCREASING DURING THE AFTERNOON AS INSTABILITY INCREASES
WITH DAYTIME HEATING. MOISTURE ADVECTION WILL INCREASE IN THE
RESULTING SOUTH/SOUTHWEST FLOW PUSHING PWAT VALUES BACK UP TO JUST
BELOW 1.5" WHICH IS NEARLY TWO STANDARD DEVIATIONS ABOVE NORMAL
FOR THIS TIME OF YEAR. THERE IS A LARGE DIFFERENCE IN MODEL
FORECAST CAPE VALUES FOR MONDAY AFTERNOON RANGING FROM 500 TO 1500
J/KG...BUT IN ANY CASE WITH RELATIVELY WEAK SHEAR AND STORM MOTION
AROUND 15KTS...THE POTENTIAL FOR SEVERE WEATHER LOOKS LOW ATTM.
THE WARMING TREND IN TEMPERATURES WILL REMAIN INTACT AS RIDGING
CONTINUES TO BUILD ACROSS THE EASTERN CONUS THROUGH MONDAY AND LOW
PRESSURE DEEPENS OVER THE INTERMOUNTAIN WEST...WITH MAX
TEMPERATURES FORECAST TO BE APPROXIMATELY 15 DEGREES ABOVE NORMAL
ON MONDAY.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
WITH THE WESTERN TOUGH SLOWLY TRANSITIONING EAST...NOT MUCH CHANGE
IS IN STORE FOR TUESDAY WITH MAX TEMPERATURES NOSING UP FURTHER
AND SHOWER/THUNDERSTORM CHANCES AGAIN MAINLY DURING THE AFTERNOON
AND EARLY EVENING. BY WEDNESDAY THE LONGWAVE TROUGH WILL HAVE
MOVED FAR ENOUGH EAST TO INCREASE DYNAMICS ACROSS THE FORECAST
AREA AND WITH PLENTY OF MOISTURE AND INSTABILITY ALREADY IN PLACE
IT LOOKS LIKELY THAT THERE WILL BE MORE WIDESPREAD THUNDERSTORM
COVERAGE. INCREASED DIRECTIONAL AND SPEED SHEAR ALOFT ALSO RAISES
THE POTENTIAL FOR MORE ORGANIZED CONVECTION BY WEDNESDAY...BUT
ATTM VALUES ARE STILL MARGINAL.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
GIVEN THE AMPLITUDE OF THE FLOW PTN PROGGED FOR THIS WEEK...EXPECT
THAT TIMING ADJUSTMENTS FOR THE EWD PROGRESS OF THE UPR TROF/CDFNT
SHOULD BE ANTICIPATED. NEVERTHELESS...THE LONG TERM FORECAST
FEATURES A CONTINUATION OF LIKELY POPS THROUGH THURSDAY FOLLOWED
BY CHC NMBRS INTO THE WEEKEND TO ACCOUNT FOR THE ADVN OF THE TROF
AND CURRENTLY PROGGED CUTOFF OVR THE GREAT LAKES REGION. PCPN AND
FRONTAL PASSAGE WL SPPRT TEMPS NR...THEN BLO THE SEASONAL AVGS FOR
THE PD.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
SCT MID CLOUDS AND A CANOPY OF CIRRUS DOMINATE THE FORECAST.
SHOWERS AND THUNDERSTORMS OVER IL/IA AS OF 23Z COULD HOLD TOGETHER
AND CROSS THE REGION DURING THE EARLY MORNING HOURS MONDAY
ACCORDING TO THE HRRR. DO NOT FORESEE ANYWHERE NEAR THE INTENSITY
THEY CURRENTLY HAVE...HOWEVER A BRIEF DROP TO MVFR VIS/CIGS IS
POSSIBLE. GIVEN CONFIDENCE IS LOW...DID NOT INCLUDE ANY PCPN
MENTION IN THE TERMINALS.
SHOWERS AND THUNDERSTORMS OVER WRN OH HAVE A LOW PROBABILITY OF
IMPACTING ZZV LATER TONIGHT...IF PCPN DOES OCCUR MVFR FOG IS
POSSIBLE TOWARD DAWN MONDAY MORNING.
.OUTLOOK.../00Z TUESDAY MONDAY THROUGH FRIDAY/...
MVFR AND PERHAPS BRIEF IFR WEATHER IS POSSIBLE IN SHOWERS AND
THUNDERSTORMS ALONG AND AHEAD OF A COLD FRONT THAT CROSSES MID
WEEK.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
455 PM EDT SUN MAY 11 2014
.SYNOPSIS...
ALTHOUGH WARM WEATHER WILL QUICKLY RETURN...RAIN CHANCES WILL
INCREASE AS THE WEEK PROGRESSES.
&&
.NEAR TERM /THROUGH MONDAY/...
ONLY MADE A SLIGHT UPDATE TO ADJUST POPS THROUGH THE NEXT SEVERAL
HOURS BASED ON RECENT SATELLITE DATA AND RADAR TRENDS AS SOME
SHOWERS HAVE POPPED UP IN OHIO. THE HI RES MODELS CONTINUE TO
INDICATE THAT FURTHER DEVELOPMENT COULD OCCUR IN OHIO
TONIGHT...WITH THE HRRR BRINGING A SECOND WAVE OVER THE NORTHERN
COUNTIES TOWARDS MORNING. AS OF NOW HOWEVER...THE MESOANALYSIS
SHOWS THAT MUCH OF THE REGION REMAINS CAPPED. WILL MAINTAIN CHANCE
POPS THROUGH THE OVERNIGHT WITH ADVANCING WARM FRONT.
OTHERWISE FORECAST REMAINS ON TRACK.
PREVIOUS DISCUSSION FOLLOWS...
PRECIP CHANCES WILL CONTINUE THROUGH THE DAY ON
MONDAY...INCREASING DURING THE AFTERNOON AS INSTABILITY INCREASES
WITH DAYTIME HEATING. MOISTURE ADVECTION WILL INCREASE IN THE
RESULTING SOUTH/SOUTHWEST FLOW PUSHING PWAT VALUES BACK UP TO JUST
BELOW 1.5" WHICH IS NEARLY TWO STANDARD DEVIATIONS ABOVE NORMAL
FOR THIS TIME OF YEAR. THERE IS A LARGE DIFFERENCE IN MODEL
FORECAST CAPE VALUES FOR MONDAY AFTERNOON RANGING FROM 500 TO 1500
J/KG...BUT IN ANY CASE WITH RELATIVELY WEAK SHEAR AND STORM MOTION
AROUND 15KTS...THE POTENTIAL FOR SEVERE WEATHER LOOKS LOW ATTM.
THE WARMING TREND IN TEMPERATURES WILL REMAIN INTACT AS RIDGING
CONTINUES TO BUILD ACROSS THE EASTERN CONUS THROUGH MONDAY AND LOW
PRESSURE DEEPENS OVER THE INTERMOUNTAIN WEST...WITH MAX
TEMPERATURES FORECAST TO BE APPROXIMATELY 15 DEGREES ABOVE NORMAL
ON MONDAY.
&&
.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
WITH THE WESTERN TOUGH SLOWLY TRANSITIONING EAST...NOT MUCH CHANGE
IS IN STORE FOR TUESDAY WITH MAX TEMPERATURES NOSING UP FURTHER
AND SHOWER/THUNDERSTORM CHANCES AGAIN MAINLY DURING THE AFTERNOON
AND EARLY EVENING. BY WEDNESDAY THE LONGWAVE TROUGH WILL HAVE
MOVED FAR ENOUGH EAST TO INCREASE DYNAMICS ACROSS THE FORECAST
AREA AND WITH PLENTY OF MOISTURE AND INSTABILITY ALREADY IN PLACE
IT LOOKS LIKELY THAT THERE WILL BE MORE WIDESPREAD THUNDERSTORM
COVERAGE. INCREASED DIRECTIONAL AND SPEED SHEAR ALOFT ALSO RAISES
THE POTENTIAL FOR MORE ORGANIZED CONVECTION BY WEDNESDAY...BUT
ATTM VALUES ARE STILL MARGINAL.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
GIVEN THE AMPLITUDE OF THE FLOW PTN PROGGED FOR THIS WEEK...EXPECT
THAT TIMING ADJUSTMENTS FOR THE EWD PROGRESS OF THE UPR TROF/CDFNT
SHOULD BE ANTICIPATED. NEVERTHELESS...THE LONG TERM FORECAST
FEATURES A CONTINUATION OF LIKELY POPS THROUGH THURSDAY FOLLOWED
BY CHC NMBRS INTO THE WEEKEND TO ACCOUNT FOR THE ADVN OF THE TROF
AND CURRENTLY PROGGED CUTOFF OVR THE GREAT LAKES REGION. PCPN AND
FRONTAL PASSAGE WL SPPRT TEMPS NR...THEN BLO THE SEASONAL AVGS FOR
THE PD.
&&
.AVIATION /21Z SUNDAY THROUGH FRIDAY/...
NO SIGNIFICANT WEATHER IS EXPECTED THE REMAINDER OF THE DAY WITH
GENERALLY LIGHT WINDS OUT OF THE SOUTHWEST AND SCT-BKN MID AND
UPPER LEVEL CLOUDS. THERE IS A SLIGHT CHANCE OF THUNDERSTORMS
OVERNIGHT AS A WARM FRONT CROSSES THE REGION.
.OUTLOOK.../MONDAY THROUGH FRIDAY/...
SCATTERED RESTRICTIONS WILL BE POSSIBLE MONDAY AND TUESDAY IN
SHOWERS OR THUNDERSTORMS WITH MORE WIDESPREAD RESTRICTIONS ON
WEDNESDAY AS A COLD FRONT IMPACTS THE AREA.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
347 PM EDT SUN MAY 11 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 347 PM EDT SUN MAY 11 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW STRONG SHORTWAVE ENERGY
ROUNDING BASE OF AMPLIFIED TROF OVER THE FOUR CORNERS REGION OF THE
SW CONUS. MODELS SHOW THIS STRONG SHORTWAVE BEGINNING TO EJECT NE
FROM WRN/CENTRAL PLAINS TONIGHT AS ITS ASSOC SFC LOW LIFTS NE
THROUGH THE PLAINS. INCREASING MOISTURE AND ISENTROPIC ASCENT AHEAD
OF THIS LOW PRES SYSTEM SHOULD SIGNAL THE BEGINNING OF A FAIRLY WET
PERIOD FOR THE CWA STARTING LATE TONIGHT AND CONTINUING INTO EARLY
TUESDAY.
TONIGHT...AS THE STRONGER SHORTWAVE BEGINS TO EJECT OUT OF THE
DEEPENING UPPER TROF THE SFC LOW PRES WILL IN TURN LIFT NE THRU THE
PLAINS. THE EVENING SHOULD REMAIN DRY...AND PERHAPS CONTINUE INTO
THE OVERNIGHT OVER THE NE HALF OF THE FCST AREA CLOSER TO DRY
LOW-LEVEL NE TRAJECTORIES OUT OF SFC HIGH PRES IN ONTARIO. MOST OF
THE MODELS SHOW INCREASING 850-700 MB MOISTURE TRANSPORT AND
ADVECTION INTO THE AREA FM THE SOUTH BTWN 06-12Z ALONG WITH
INCREASING 300-305K WAA/ISENTROPIC ASCENT AHEAD OF THE APPROACHING
LOW PRES SYSTEM. MODELS ALSO INDICATE A SUBTLE SHORTWAVE WILL LIFT
NE INTO THE UPPER MISSISSIPPI VALLEY LATE TONIGHT THAT WILL FURTHER
AID THE DEVELOPMENT/SPREAD OF SHRA NE INTO UPPER MI DURING THE
OVERNIGHT. NOT MUCH INSTABILITY IS NOTED PER 0-3KM MUCAPE OFF THE
NAM/GFS. WITH A COUPLE HUNDRED J/KG AND SHOWALTER INDEX FALLING JUST
BLO 0C OVER THE FAR SCNTRL LATE TONIGHT IN MOST MODEL
GUIDANCE...WILL CONTINUE THE MENTION OF THUNDER IN THAT AREA LATE
TONIGHT.
MONDAY...WITH H85 WARM FRONT IN THE VICINITY...MODELS SHOW CONTINUED
MOISTURE TRANSPORT/ADVECTION AT H85-H7 ACROSS THE FRONTAL BOUNDARY
AS PWATS OVER OUR AREA RISE TO AROUND 1.5 INCHES OR WELL OVER 200
PCT OF NORMAL. SHORTWAVE/PV ANAMOLY EMERGING NORTHEAST OUT OF THE
WESTERN CONUS TROUGH WILL SPREAD AREA OF H85-H5 Q-VECTOR CONVERGENCE
INTO THE UPPER GREAT LAKES BY MONDAY AFTERNOON. DESPITE THESE
FAVORABLE FACTORS FOR SHOWERS...MODELS STILL DIFFER SOMEWHAT ON
PLACEMENT OF MAXIMUM MOISTURE ADVECTION...WITH THE GFS AND NAM
INDICATING BEST MOISTURE ADVECTION WEST AND THE REG GEM TO THE
EAST. HOWEVER CORFIDI VECTORS...BOTH FORWARD AND BACKWARD
PROPAGATING...ARE GENERALLY ORIENTED FROM WEST TO EAST ACROSS THE
FCST AREA WHICH WOULD ARGUE SHOWERS MAKING IT INTO THE WRN FCST AREA
SHOULD ADVECT INTO THE ERN COUNTIES AS WELL. GOING FCST LIKELY POPS
STILL SEEM REASONABLE CONSIDERING THE H85 FRONT IS IN THE VICINTY.
WILL CONTINUE IDEA OF LIKELY POPS WEST IN THE MORNING SPREADING EAST
INTO THE AFTERNOON HRS. ALSO WILL CONTINUE TO KEEP MENTION OF
TSRA MAINLY OVER SOUTH HALF INTO THE WESTERN CWA ALONG NORTHERN
GRADIENT OF ELEVATED INSTABILITY WITH SEVERAL HUNDRED J/KG OF
ELEVATED CAPE AND NEG SHOWALTER INDICES. BIGGEST THREAT WITH ANY
TSRA WILL BE HEAVY RAIN GIVEN HIGH PWATS ACROSS AREA. ANY HEAVY RAIN
OVER THE WRN COUNTIES WILL CONTINUE TO ADD MORE RUNOFF TO RIVERS
ALREADY RUNNING NEAR BANKFULL...ESPECIALLY THE STURGEON...TRAP ROCK
AND MICHIGAMME RIVERS.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 329 PM EDT SUN MAY 11 2014
AT THE START OF THE PERIOD /00Z TUE/ MODELS ARE IN DECENT LARGE
SCALE AGREEMENT IN SHOWING A SHARP AND DEEP 500MB TROUGH FROM THE
SASK/MANITOBA BORDER S ACROSS THE DAKOTAS THEN TO THE FOUR CORNERS
REGION. A 1004MB SFC LOW WILL BE SOMEWHERE IN THE SERN MN TO NWRN
WI. MODELS HAVE BEEN TRENDING TOWARD THE CURRENT SOLUTION THAT TAKES
THE SFC LOW W OF THE CWA TO JUST N OF THE MN ARROWHEAD BY 12Z TUE.
WITH THE MORE NLY TRACK...MODELS ARE NOW SHOWING THE SFC WARM FRONT
MOVING INTO THE FAR SRN CWA MON NIGHT...BUT WITH COLD LAKE TEMPS AND
CONVECTION EXPECTED ALONG THE FRONT...CONFIDENCE IN THE FRONT MOVING
THAT FAR N IS LOW. FORCING FROM UPPER LEVEL HEIGHT FALLS FROM THE
DEEPENING TROUGH...GOOD MOISTURE TRANSPORT AND ISENTROPIC ASCENT
WILL FAVOR PERIODS OF MODERATE RAIN SHOWERS MON NIGHT INTO EARLY
TUE. THE OCCLUDED/COLD FRONT WILL MOVE THROUGH FROM LATE MON NIGHT
INTO TUE...BRINGING AN END TO THE BULK OF THE PRECIP. SOME SHOWERS
COULD REDEVELOP BEHIND THE FRONT AS CLEARING OVER THE WRN U.P. MAY
ALLOW FOR ENOUGH INSTABILITY. MODELS GENERALLY SHOW ADDITIONAL QPF
AMOUNTS OF AN INCH...BUT THAT WILL BE HIGHLY DEPENDENT ON EXACT
DETAILS OF CONVECTION...MAKING EXACT PRECIP AMOUNTS HIGHLY
UNCERTAIN. INSTABILITY FOR CONVECTION WILL ALSO BE HIGHLY UNCERTAIN
DUE TO DEPENDENCY ON WARM FRONTAL LOCATION AND OTHER CONVECTION. IF
THE FRONT CAN MAKE IT FARTHER N...THE WARM NOSE AT 900MB MAY BE
STRONG ENOUGH TO LEAD TO GREATER ELEVATED CONVECTION. GFS AND NAM
ARE SHOWING UP TO AROUND 1000 J/KG OF ELEVATED CAPE OVER THE
SCENTRAL CWA...BUT STILL THINK THAT IS NOT AS LIKELY AS THE FRONT
WILL PROBABLY STAY FARTHER S. IF THE WORST CASE SCENARIO OF THE
FARTHER N FRONTAL POSITION DOES OCCUR...SOME HAIL WOULD BE POSSIBLE
SCENTRAL. THE ADDITIONAL QPF AMOUNTS /COMBINED WITH PRECIP ON MON/
WOULD LIKELY LEAD TO ADDITIONAL FLOODING CONCERNS ON AREA RIVERS
THAT ALREADY HAVE ELEVATED LEVELS.
THE UPPER TROUGH MOVES OVERHEAD THROUGH MUCH OF THE REST OF THE WORK
WEEK...ALTHOUGH THE ECMWF CLOSES IT OFF INTO A LOW THU INTO FRI. THE
ECMWF SOLUTION WOULD RESULT IN MORE WIDESPREAD PRECIP THU INTO
FRI...BUT THE GFS AND GEM SOLUTIONS WITH THE OPEN TROUGH WOULD LEAD
TO SCATTERED SHOWER ACTIVITY MAINLY DURING PEAK HEATING WED THROUGH
FRI. THIS DUE TO 850MB TEMPS OF -2C TO -4C WED THROUGH FRI NIGHT
/AND AS COLD AS -7C IF THE ECMWF SOLUTION PANS OUT/. OF
COURSE...THIS WILL LEAD TO A RETURN OF SIGNIFICANTLY BELOW NORMAL
TEMPS /10-15 DEGREES BELOW NORMAL/.
NEXT WEEKEND LOOKS DRIER AND WARMER AS RIDGING MOVES OVERHEAD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 151 PM EDT SUN MAY 11 2014
LINGERING DRY AIR AT THE LOW LEVELS WILL ENSURE VFR CONDITIONS
CONTINUE AT KIWD/KCMX/KSAW INTO THE EVENING HRS. LATE TONIGHT...
NORTHWARD ADVANCING LOW PRESSURE AND A WARM FRONT WILL SPREAD SHRA
TOWARD THE UPPER LAKES. THERE IS STILL SOME UNCERTAINTY IN HOW FAST
PCPN WILL DEVELOP. KIWD HAS THE BEST CHC OF CONDITIONS FALLING TO
MVFR AROUND 08Z WITH THE ONSET OF RAIN. EXPECT ALL SITES TO QUICKLY
FALL TO IFR OR LIFR IN LOWERING STRATUS BY 12Z OR SHORTLY THEREAFTER
WITH CONTINUED SHOWERS AND ADVECTION OF HIGHER DEWPOINTS INTO THE
AREA.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 347 PM EDT SUN MAY 11 2014
NE WINDS 15-25 KTS THIS EVENING WILL BEGIN TO INCREASE OVER WESTERN
PORTIONS OF LK SUPERIOR LATE TONIGHT AND MORE SO ON MONDAY AS LOW
PRESSURE APPROACHES FROM THE SOUTHWEST. DECIDED TO REPLACE GALE
WATCH WITH GALE WARNING OVER WESTERN TWO ZONES LATE TONIGHT THROUGH
TUE EVENING. WINDS OVER THE REST OF THE LAKE WILL STAY AT OR BLO 30
KTS. WINDS DIMINISH LATER MONDAY NIGHT AND THEN SWITCH TO THE WEST
TO 20-25 KTS ON TUESDAY. LOW SLOWLY SLIDES TO THE NORTHEAST OF LK
SUPERIOR REST OF THE WEEK...RESULTING IN NORTHWEST WINDS MAINLY
STAYING BLO 20 KTS.
&&
.HYDROLOGY...
ISSUED AT 329 PM EDT SUN MAY 11 2014
HIGHS MOSTLY IN THE 60S TODAY WILL RESULT IN ADDITIONAL SNOWMELT
OVER HIGHER TERRAIN OF NORTHERN UPR MICHIGAN. MINIMAL RAIN AMOUNTS
ARE EXPECTED THROUGH AT LEAST EARLY TONIGHT...BUT RAIN CHANCES
INCREASE LATE TONIGHT INTO TUESDAY MORNING. THERE IS A POTENTIAL FOR
MODERATE TO HEAVY RAIN OVER THE AREAS THAT ARE STILL MELTING
SNOW...SO THE RECENT HIGHER RIVER LEVELS WILL CONTINUE THROUGH MUCH
OF THE UPCOMING WEEK. THE FLOOD WARNING CONTINUES FOR THE STURGEON
RIVER NEAR CHASSELL...WHILE ADVISORIES ARE IN PLACE FOR OTHER
PORTIONS OF THE STURGEON RIVER IN HOUGHTON AND BARAGA COUNTIES AS
WELL AS PORTIONS OF THE MICHIGAMME RIVER. IF HEAVIER RAINS
MATERIALIZE EARLY THIS WEEK... ADDITIONAL ADVISORIES AND WARNINGS
MAY BE NEEDED. THOSE LIVING NEAR RIVERS...CREEKS...AND STREAMS
SHOULD CONTINUE TO MONITOR THE LATEST RIVER LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 6 AM EDT /5 AM CDT/ MONDAY TO MIDNIGHT EDT /11
PM CDT/ MONDAY NIGHT FOR LSZ162.
GALE WARNING FROM 10 AM TO 11 PM EDT MONDAY FOR LSZ263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...VOSS
LONG TERM...TITUS
AVIATION...VOSS
MARINE...VOSS
HYDROLOGY...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
330 PM EDT SUN MAY 11 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 454 AM EDT SUN MAY 11 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A SHORTWAVE HEADING SE
TOWARD THE SRN ROCKIES...LEADING THE TROF AMPLIFICATION DOWNSTREAM
OF ADVERTISED BUILDING RIDGE JUST OFF THE W COAST. DEEPENING TROF
AND SHORTWAVE WILL BRING THE NEXT ROUND OF WIDESPREAD WET WEATHER TO
THE UPPER GREAT LAKES...BEGINNING AS EARLY AS LATER TONIGHT. AHEAD
OF THE AMPLIFYING WRN TROF...A SHORTWAVE IS LIFTING THRU THE UPPER
MISSISSIPPI VALLEY. WITH LARGER SCALE RIDGE BUILDING OVER THE
MISSISSIPPI VALLEY/WRN LAKES DOWNSTREAM OF THE DEEPENING WRN
TROF...WAVE IS WEAKENING. LATEST RADAR IMAGERY SHOWS ISOLD/SCT
-SHRA ALONG THE MI/WI BORDER AREA. WITH VERY DRY MASS OVER
THE AREA (NOTE THE VERY DRY COLUMN SAMPLED BY 00Z KGRB SOUNDING)...
PCPN HAS BEEN ON THE LIGHT SIDE WITH MUCH OF IT NOT MORE THAN
SPRINKLES.
SOMEWHAT SURPRISED THAT -SHRA/SPRINKLES ARE HOLDING TOGETHER GIVEN
THE ANTECEDANT DRY AIR MASS AND THE SHORTWAVE/FORCING WEAKENING
UNDER DEVELOPING HEIGHT RISES. IN ANY EVENT...ISOLD/SCT
-SHRA/SPRINKLES SHOULD MOVE NE ACROSS ALL BUT THE FAR ERN FCST AREA
DURING THE MORNING. AFTER THE MORNING HRS...EXPECT A DRY AFTN UNDER
CONTINUED HEIGHT RISES AS RIDGE BUILDS THRU THE WRN GREAT LAKES
DOWNSTREAM OF ROCKIES TROF. YESTERDAY...A NUMBER OF MODELS WERE
SUGGESTING SOME AFTN CONVECTION...ESPECIALLY THE NAM. THAT IDEA WAS
DISREGARDED AS MODELS WERE OVERFORECASTING LOW-LEVEL MOISTURE AND
THUS INSTABILITY. WELL...TODAYS 00Z MODELS RUNS ARE ALMOST ALL
ONBOARD WITH A DRY AFTN AS A RESULT OF CORRECTING THE
MOISTURE/INSTABILITY DOWNWARD. CLOUDS WILL THIN SOME IN THE
AFTN...ALLOWING TEMPS TO RISE WELL INTO THE 60S TO AROUND 70F AWAY
FROM LAKE MODERATION.
AS STRONGER SHORTWAVE BEGINS TO EJECT OUT OF DEEPENING UPPER TROF
DRIFTING TOWARD THE WRN PLAINS TONIGHT...SFC LOW PRES WILL BEGIN TO
LIFT NE THRU THE PLAINS. ALTHOUGH THE EVENING MAY BE DRY...
ESPECIALLY OVER THE NE HALF OF THE FCST AREA CLOSER TO DRY LOW-LEVEL
NE TRAJECTORIES OUT OF SFC HIGH PRES IN ONTARIO...MOST OF THE MODELS
SHOW HIGHER MID LEVEL RH AND PCPN ARRIVING FROM THE SW THRU THE
NIGHT AS WAA/ISENTROPIC ASCENT REGIME SPREADS N. THERE ARE
INDICATIONS OF A SUBTLE SHORTWAVE LIFTING NE INTO THE UPPER
MISSISSIPPI VALLEY LATE TONIGHT...AND THAT WILL FURTHER AID THE
DEVELOPMENT/SPREAD OF SHRA NE INTO UPPER MI DURING THE OVERNIGHT.
NOT MUCH INSTABILITY IS NOTED PER 0-3KM MUCAPE OFF THE NAM/GFS. WITH
A COUPLE HUNDRED J/KG AND SHOWALTER INDEX FALLING JUST BLO 0 OVER
THE FAR SCNTRL LATE TONIGHT IN MOST MODEL GUIDANCE...WILL INCLUDE A
THUNDER MENTION IN THAT AREA LATE TONIGHT.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 329 PM EDT SUN MAY 11 2014
AT THE START OF THE PERIOD /00Z TUE/ MODELS ARE IN DECENT LARGE
SCALE AGREEMENT IN SHOWING A SHARP AND DEEP 500MB TROUGH FROM THE
SASK/MANITOBA BORDER S ACROSS THE DAKOTAS THEN TO THE FOUR CORNERS
REGION. A 1004MB SFC LOW WILL BE SOMEWHERE IN THE SERN MN TO NWRN
WI. MODELS HAVE BEEN TRENDING TOWARD THE CURRENT SOLUTION THAT TAKES
THE SFC LOW W OF THE CWA TO JUST N OF THE MN ARROWHEAD BY 12Z TUE.
WITH THE MORE NLY TRACK...MODELS ARE NOW SHOWING THE SFC WARM FRONT
MOVING INTO THE FAR SRN CWA MON NIGHT...BUT WITH COLD LAKE TEMPS AND
CONVECTION EXPECTED ALONG THE FRONT...CONFIDENCE IN THE FRONT MOVING
THAT FAR N IS LOW. FORCING FROM UPPER LEVEL HEIGHT FALLS FROM THE
DEEPENING TROUGH...GOOD MOISTURE TRANSPORT AND ISENTROPIC ASCENT
WILL FAVOR PERIODS OF MODERATE RAIN SHOWERS MON NIGHT INTO EARLY
TUE. THE OCCLUDED/COLD FRONT WILL MOVE THROUGH FROM LATE MON NIGHT
INTO TUE...BRINGING AN END TO THE BULK OF THE PRECIP. SOME SHOWERS
COULD REDEVELOP BEHIND THE FRONT AS CLEARING OVER THE WRN U.P. MAY
ALLOW FOR ENOUGH INSTABILITY. MODELS GENERALLY SHOW ADDITIONAL QPF
AMOUNTS OF AN INCH...BUT THAT WILL BE HIGHLY DEPENDENT ON EXACT
DETAILS OF CONVECTION...MAKING EXACT PRECIP AMOUNTS HIGHLY
UNCERTAIN. INSTABILITY FOR CONVECTION WILL ALSO BE HIGHLY UNCERTAIN
DUE TO DEPENDENCY ON WARM FRONTAL LOCATION AND OTHER CONVECTION. IF
THE FRONT CAN MAKE IT FARTHER N...THE WARM NOSE AT 900MB MAY BE
STRONG ENOUGH TO LEAD TO GREATER ELEVATED CONVECTION. GFS AND NAM
ARE SHOWING UP TO AROUND 1000 J/KG OF ELEVATED CAPE OVER THE
SCENTRAL CWA...BUT STILL THINK THAT IS NOT AS LIKELY AS THE FRONT
WILL PROBABLY STAY FARTHER S. IF THE WORST CASE SCENARIO OF THE
FARTHER N FRONTAL POSITION DOES OCCUR...SOME HAIL WOULD BE POSSIBLE
SCENTRAL. THE ADDITIONAL QPF AMOUNTS /COMBINED WITH PRECIP ON MON/
WOULD LIKELY LEAD TO ADDITIONAL FLOODING CONCERNS ON AREA RIVERS
THAT ALREADY HAVE ELEVATED LEVELS.
THE UPPER TROUGH MOVES OVERHEAD THROUGH MUCH OF THE REST OF THE WORK
WEEK...ALTHOUGH THE ECMWF CLOSES IT OFF INTO A LOW THU INTO FRI. THE
ECMWF SOLUTION WOULD RESULT IN MORE WIDESPREAD PRECIP THU INTO
FRI...BUT THE GFS AND GEM SOLUTIONS WITH THE OPEN TROUGH WOULD LEAD
TO SCATTERED SHOWER ACTIVITY MAINLY DURING PEAK HEATING WED THROUGH
FRI. THIS DUE TO 850MB TEMPS OF -2C TO -4C WED THROUGH FRI NIGHT
/AND AS COLD AS -7C IF THE ECMWF SOLUTION PANS OUT/. OF
COURSE...THIS WILL LEAD TO A RETURN OF SIGNIFICANTLY BELOW NORMAL
TEMPS /10-15 DEGREES BELOW NORMAL/.
NEXT WEEKEND LOOKS DRIER AND WARMER AS RIDGING MOVES OVERHEAD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 151 PM EDT SUN MAY 11 2014
LINGERING DRY AIR AT THE LOW LEVELS WILL ENSURE VFR CONDITIONS
CONTINUE AT KIWD/KCMX/KSAW INTO THE EVENING HRS. LATE TONIGHT...
NORTHWARD ADVANCING LOW PRESSURE AND A WARM FRONT WILL SPREAD SHRA
TOWARD THE UPPER LAKES. THERE IS STILL SOME UNCERTAINTY IN HOW FAST
PCPN WILL DEVELOP. KIWD HAS THE BEST CHC OF CONDITIONS FALLING TO
MVFR AROUND 08Z WITH THE ONSET OF RAIN. EXPECT ALL SITES TO QUICKLY
FALL TO IFR OR LIFR IN LOWERING STRATUS BY 12Z OR SHORTLY THEREAFTER
WITH CONTINUED SHOWERS AND ADVECTION OF HIGHER DEWPOINTS INTO THE
AREA.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 454 AM EDT SUN MAY 11 2014
WINDS LESS THAN 20 KTS THROUGH THIS EVENING. WINDS BEGIN TO INCREASE
OVER WESTERN PORTIONS OF LK SUPERIOR LATE TONIGHT AND MORE SO ON
MONDAY AS LOW PRESSURE APPROACHES FROM THE SOUTHWEST. FREQUENT GALE
GUSTS APPEAR LIKELY OVER FAR WEST...SO HAVE ISSUED A GALE WATCH.
WINDS OVER THE REST OF THE LAKE WILL STAY AT OR BLO 30 KTS. WINDS
DIMINISH LATER MONDAY NIGHT AND THEN SWITCH TO THE WEST TO 20-25 KTS
ON TUESDAY. LOW SLOWLY SLIDES TO THE NORTHEAST OF LK SUPERIOR REST
OF THE WEEK...RESULTING IN NORTHWEST WINDS MAINLY STAYING BLO 20 KTS.
&&
.HYDROLOGY...
ISSUED AT 329 PM EDT SUN MAY 11 2014
HIGHS MOSTLY IN THE 60S TODAY WILL RESULT IN ADDITIONAL SNOWMELT
OVER HIGHER TERRAIN OF NORTHERN UPR MICHIGAN. MINIMAL RAIN AMOUNTS
ARE EXPECTED THROUGH AT LEAST EARLY TONIGHT...BUT RAIN CHANCES
INCREASE LATE TONIGHT INTO TUESDAY MORNING. THERE IS A POTENTIAL FOR
MODERATE TO HEAVY RAIN OVER THE AREAS THAT ARE STILL MELTING
SNOW...SO THE RECENT HIGHER RIVER LEVELS WILL CONTINUE THROUGH MUCH
OF THE UPCOMING WEEK. THE FLOOD WARNING CONTINUES FOR THE STURGEON
RIVER NEAR CHASSELL...WHILE ADVISORIES ARE IN PLACE FOR OTHER
PORTIONS OF THE STURGEON RIVER IN HOUGHTON AND BARAGA COUNTIES AS
WELL AS PORTIONS OF THE MICHIGAMME RIVER. IF HEAVIER RAINS
MATERIALIZE EARLY THIS WEEK... ADDITIONAL ADVISORIES AND WARNINGS
MAY BE NEEDED. THOSE LIVING NEAR RIVERS...CREEKS...AND STREAMS
SHOULD CONTINUE TO MONITOR THE LATEST RIVER LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 6 AM EDT /5 AM CDT/ MONDAY TO MIDNIGHT EDT /11
PM CDT/ MONDAY NIGHT FOR LSZ162.
GALE WARNING FROM 10 AM TO 11 PM EDT MONDAY FOR LSZ263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...VOSS
MARINE...JLA
HYDROLOGY...TITUS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
204 PM EDT SUN MAY 11 2014
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 454 AM EDT SUN MAY 11 2014
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A SHORTWAVE HEADING SE
TOWARD THE SRN ROCKIES...LEADING THE TROF AMPLIFICATION DOWNSTREAM
OF ADVERTISED BUILDING RIDGE JUST OFF THE W COAST. DEEPENING TROF
AND SHORTWAVE WILL BRING THE NEXT ROUND OF WIDESPREAD WET WEATHER TO
THE UPPER GREAT LAKES...BEGINNING AS EARLY AS LATER TONIGHT. AHEAD
OF THE AMPLIFYING WRN TROF...A SHORTWAVE IS LIFTING THRU THE UPPER
MISSISSIPPI VALLEY. WITH LARGER SCALE RIDGE BUILDING OVER THE
MISSISSIPPI VALLEY/WRN LAKES DOWNSTREAM OF THE DEEPENING WRN
TROF...WAVE IS WEAKENING. LATEST RADAR IMAGERY SHOWS ISOLD/SCT
-SHRA ALONG THE MI/WI BORDER AREA. WITH VERY DRY MASS OVER
THE AREA (NOTE THE VERY DRY COLUMN SAMPLED BY 00Z KGRB SOUNDING)...
PCPN HAS BEEN ON THE LIGHT SIDE WITH MUCH OF IT NOT MORE THAN
SPRINKLES.
SOMEWHAT SURPRISED THAT -SHRA/SPRINKLES ARE HOLDING TOGETHER GIVEN
THE ANTECEDANT DRY AIR MASS AND THE SHORTWAVE/FORCING WEAKENING
UNDER DEVELOPING HEIGHT RISES. IN ANY EVENT...ISOLD/SCT
-SHRA/SPRINKLES SHOULD MOVE NE ACROSS ALL BUT THE FAR ERN FCST AREA
DURING THE MORNING. AFTER THE MORNING HRS...EXPECT A DRY AFTN UNDER
CONTINUED HEIGHT RISES AS RIDGE BUILDS THRU THE WRN GREAT LAKES
DOWNSTREAM OF ROCKIES TROF. YESTERDAY...A NUMBER OF MODELS WERE
SUGGESTING SOME AFTN CONVECTION...ESPECIALLY THE NAM. THAT IDEA WAS
DISREGARDED AS MODELS WERE OVERFORECASTING LOW-LEVEL MOISTURE AND
THUS INSTABILITY. WELL...TODAYS 00Z MODELS RUNS ARE ALMOST ALL
ONBOARD WITH A DRY AFTN AS A RESULT OF CORRECTING THE
MOISTURE/INSTABILITY DOWNWARD. CLOUDS WILL THIN SOME IN THE
AFTN...ALLOWING TEMPS TO RISE WELL INTO THE 60S TO AROUND 70F AWAY
FROM LAKE MODERATION.
AS STRONGER SHORTWAVE BEGINS TO EJECT OUT OF DEEPENING UPPER TROF
DRIFTING TOWARD THE WRN PLAINS TONIGHT...SFC LOW PRES WILL BEGIN TO
LIFT NE THRU THE PLAINS. ALTHOUGH THE EVENING MAY BE DRY...
ESPECIALLY OVER THE NE HALF OF THE FCST AREA CLOSER TO DRY LOW-LEVEL
NE TRAJECTORIES OUT OF SFC HIGH PRES IN ONTARIO...MOST OF THE MODELS
SHOW HIGHER MID LEVEL RH AND PCPN ARRIVING FROM THE SW THRU THE
NIGHT AS WAA/ISENTROPIC ASCENT REGIME SPREADS N. THERE ARE
INDICATIONS OF A SUBTLE SHORTWAVE LIFTING NE INTO THE UPPER
MISSISSIPPI VALLEY LATE TONIGHT...AND THAT WILL FURTHER AID THE
DEVELOPMENT/SPREAD OF SHRA NE INTO UPPER MI DURING THE OVERNIGHT.
NOT MUCH INSTABILITY IS NOTED PER 0-3KM MUCAPE OFF THE NAM/GFS. WITH
A COUPLE HUNDRED J/KG AND SHOWALTER INDEX FALLING JUST BLO 0 OVER
THE FAR SCNTRL LATE TONIGHT IN MOST MODEL GUIDANCE...WILL INCLUDE A
THUNDER MENTION IN THAT AREA LATE TONIGHT.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 454 AM EDT SUN MAY 11 2014
AGREEMENT IS HIGH IN OVERALL LARGER SCALE PATTERN FOR THE UPCOMING
WEEK. FLOW IS HIGHLY AMPLIFIED. INITIALY THIS WEEK TROUGH OVER THE
WESTERN CONUS THIS MORNING SLIDES ACROSS THE CENTRAL CONUS. SFC-H85
LOW PRESSURE BEGINS TO FORM TODAY OVER THE SOUTHERN PLAINS AND THIS
LOW LIFTS TOWARD UPPER MISSISSIPPI RIVER VALLEY BY DAYBREAK ON
MONDAY. SFC WARM FRONT SHOULD STAY SOUTH OF UPR MICHIGAN...MAINLY
OVER SOUTHERN/CENTRAL WI ACROSS CENTRAL LOWER MICHIGAN. EASTERLY
LOW-LEVEL WINDS OFF THE COLD GREAT LAKES TO THE NORTH OF THE FRONT
ALONG WITH SHRA/TSRA FIRING ALONG THE FRONT SHOULD KEEP THE WARM
FRONT FROM MOVING INTO UPR MICHIGAN ON MONDAY. WARM FRONT SOUTH OF
HERE ALONG WITH EASTERLY WINDS SHOULD KEEP TEMPS COOLER ON MONDAY
THAN THIS WEEKEND.
H85 WARM FRONT WILL BE IN THE VICINITY THOUGH AND THERE IS MOISTURE
TRANSPORT AT H85-H7 AIMED INTO THE H85 FRONT ALLOWING PWATS OVER 1.5
INCHES OR WELL OVER 200 PCT OF NORMAL TO PUSH NORTHWARD ACROSS UPPER
GREAT LAKES REGION. SHORTWAVE/PV ANAMOLY EMERGING NORTHEAST OUT OF
THE LARGE WESTERN CONUS TROUGH RESULTS IN AREA OF H85-H5 Q-VECTOR
CONVERGENCE SPREADING OVER UPPER GREAT LAKES ON MONDAY. ADDITIONAL
LIFT WILL BE PROVIDED VIA 250MB JET STREAK LIFTING NNE-SSW AHEAD OF
MAIN TROUGH AND ALSO ANOTHER SLIDING WNW-ESE OVER NORTHERN ONTARIO
TOWARD QUEBEC. AT FIRST GLANCE...A LOT OF THINGS ARE FAVORABLE FOR
MULTIPLE PERIODS OF SHOWERS OVER UPR MICHIGAN ON MONDAY. YET...THE
INSTABILITY BOTH ELEVATED /1-6KM MUCAPE/ AND AT THE SFC /MLCAPE/ IS
NOT AS FAVORABLE...WITH GRADIENT OF BOTH TO SOUTH AND SOUTHWEST OF
UPR MICHIGAN THROUGH THE DAY. MODELS DIFFER ON PLACEMENT OF MAXIMUM
MOISTURE ADVECTION AND THIS WILL HAVE DIRECT BEARING ON WHETHER
WESTERN HALF OF CWA OR EASTERN HALF OF CWA SEES MOST RAIN ON MONDAY.
TOUGH TO TELL AT THIS POINT WHICH IDEA WILL BE CORRECT. CORFIDI
VECTORS...BOTH FORWARD AND BACKWARD PROPAGATING...ARE ORIENTED
GENERALLY FROM WEST TO EAST ALONG AND SOUTH OF UPR MICHIGAN...WHICH
LIKELY WILL KEEP PERIODS OF PERSISTENT/HEAVIEST SHRA/TSRA TO SOUTH
OF THE AREA SINCE THAT IS WHERE PRIME GENESIS REGION FOR SHRA/TSRA
WILL BE ALONG THE SFC WARM FRONT. PERFER THE LOOK OF THE ECMWF/UKMET
WHICH KEEP THE TRACK OF HIGHEST QPF ONLY OVER SCNTRL CWA...WITH
LIGHTER AMOUNTS FARTHER NORTH AWAY FM THE SFC WARM FRONT. EVEN
SO...GOING LIKELY POPS SEEM ON TRACK WITH H85 FRONT IN VICINTY.
KEPT SMALL MENTION OF TSRA MAINLY OVER SOUTH HALF INTO THE EASTERN
CWA ALONG NORTH GRADIENT OF ELEVATED INSTABILITY. SPC DAY2 SEVERE
RISK KEEPS SLIGHT PROBABILITIES FARTHER SOUTH...BUT DOES HIGHLIGHT
SOUTHERN TIER OF CWA FOR A 5 PCT RISK.
NEXT SURGE OF SHRA/TSRA DEVELOP MONDAY NIGHT IN RESPONSE TO
SHARPENING TROUGH ALOFT. SFC LOW HAS TRENDED FARTHER NORTH OVER TIME
WITH SFC LOW LIFTING ACROSS WESTERN LK SUPERIOR BY TUESDAY MORNING.
BEFORE THAT...LARGE SCALE ASCENT DEVELOPS DUE TO THE DEEPENING OF
TROUGH ALOFT AND INCREASINGLY DIFFLUENT FLOW ALOFT. THOUGH SFC WARM
FRONT STAYS MAINLY SOUTH OF UPR MICHIGAN...H85 WARM FRONT WILL
PROVIDE MAIN FOCUS FOR SHRA/TSRA MONDAY NIGHT INTO TUESDAY MORNING
AS ANOTHER SURGE OF H85-H7 MOISTURE ADVECTION INTERSECTS THE
BOUNDARY. GFS SEEMS TOO QUICK IN SLIDING THIS WHOLE SYSTEM TO THE
EAST. ECMWF/UKMET AND GEM-NH ARE SLOWER WHICH MAKES SENSE WITH THE
SHARPER TROUGH ALOFT. GIVEN PWATS STILL OVER 200 PCT OF
NORMAL...MODERATE TO HEAVY RAIN COULD OCCUR. DECENT SIGNAL FROM
PREFERRED MODELS THAT HEAVIEST RAIN IMPACTS MAINLY NORTHERN
CWA...INCLUDING THE KEWEENAW PENINSULA. OBVIOUSLY WITH THE SNOWMELT
AND HIGHER RIVER FLOWS THAT ARE CURRENTLY OCCURRING THIS WOULD NOT BE
A GOOD SITUATION IF IT WORKED OUT THIS WAY. SIMILAR TO FORECAST ON
MONDAY...SINCE THE SFC WARM FRONT IS STILL SOUTH OF THE AREA...SFC
SHRA/TSRA ONGOING ALONG THE FRONT COULD VERY WELL IMPACT THIS ENTIRE
SCENARIO...ESPECIALLY AS STORM MOTIONS ARE FORECAST TO BE FROM SW-
NE...SUGGESTING THAT IF CLUSTER OF STORMS FORM FARTHER SOUTH CLOSER
TO SFC WARM FRONT THEY COULD GLIDE OVER EASTERN CWA AND GENERALLY
BYPASS THE WESTERN CWA. CONDIFENCE IN ANY OF THESE TYPE OF DETAILS
REMAINS LOW ATTM.
AS THE SFC LOW LIFTS NORTH OF LK SUPERIOR BY TUESDAY AFTN...EXPECT
DRYING TO SPREAD IN FROM THE WEST...DIMINISHING THEN SHUTTING OFF
ADDITIONAL PRECIPITATION. THOUGH SKIES WILL NOT COMPLETELY CLEAR OUT
AS A LOT OF H85 MOISTURE REMAINS...EVEN SHALLOW MIXING WITH THE WEST
LOW-LEVEL WINDS SHOULD RESULT IN TEMPS PUSHING INTO THE 60S OVER ALL
BUT THE FAR WEST/NORTHWEST AND EAST CWA.
QUESTION FOR THE REST OF THE WEEK IS NOT IF IT WILL BE COOL AND
UNSETTLED BUT TO WHAT DEGREE. ECMWF IS BACK TO SHOWING A VERY DEEP
TROUGH ALOFT THURSDAY INTO FRIDAY...EVEN TO THE POINT OF BECOMING
CLOSED OFF AROUND THURSDAY. PREVIOUS RUNS OF ECMWF HAD BACKED AWAY
FM STRONGER WAVE WRAPPING AROUND THE EDGE OF THE TROUGH LATE THIS
WEEK BUT NOW ITS BACK. GIVEN H85 TEMPS -2C TO -4C FALLING TO BLO -6C
AS THIS WAVE LIFTS OVER THE REGION...CERTAINLY POSSIBLE THAT SOME
SNOW COULD OCCUR THURSDAY INTO FRIDAY FOR ALMOSTL ANYWHERE IN THE
CWA. CONSENSUS OF THAT WRAPPED UP ECMWF SOLUTION ALONG WITH OTHER
AVAILABLE MEDIUM RANGE MODELS RESULTED IN LOW CHANCES ATTM...WITH
MOST MENTION OF SNOW ONLY OCCURRING LATER AT NIGHT INTO THE MORNING
BEFORE BLYR WARMS ENOUGH FOR JUST RAIN. SYSTEM WILL BE SOMETHING TO
KEEP EYE ON AS WE GET LATER INTO THE WEEK. AT THE LEAST EVEN IF WE
GET BY WITHOUT SEEING ANY SNOW...TEMPS WILL FALL TO WELL BELOW
NORMAL VALUES AGAIN. HIGHS MID-LATE WEEK LIKELY WILL STAY IN THE 40S
OVER MUCH OF NORTHERN UPR MICHIGAN CLOSER TO LK SUPERIOR AND ONLY IN
THE 50S OVER SOUTHERN CWA. NIGHTTIME LOWS WILL BE AROUND FREEZING
FOR MUCH OF THE CWA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 151 PM EDT SUN MAY 11 2014
LINGERING DRY AIR AT THE LOW LEVELS WILL ENSURE VFR CONDITIONS
CONTINUE AT KIWD/KCMX/KSAW INTO THE EVENING HRS. LATE TONIGHT...
NORTHWARD ADVANCING LOW PRESSURE AND A WARM FRONT WILL SPREAD SHRA
TOWARD THE UPPER LAKES. THERE IS STILL SOME UNCERTAINTY IN HOW FAST
PCPN WILL DEVELOP. KIWD HAS THE BEST CHC OF CONDITIONS FALLING TO
MVFR AROUND 08Z WITH THE ONSET OF RAIN. EXPECT ALL SITES TO QUICKLY
FALL TO IFR OR LIFR IN LOWERING STRATUS BY 12Z OR SHORTLY THEREAFTER
WITH CONTINUED SHOWERS AND ADVECTION OF HIGHER DEWPOINTS INTO THE
AREA. &&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 454 AM EDT SUN MAY 11 2014
WINDS LESS THAN 20 KTS THROUGH THIS EVENING. WINDS BEGIN TO INCREASE
OVER WESTERN PORTIONS OF LK SUPERIOR LATE TONIGHT AND MORE SO ON
MONDAY AS LOW PRESSURE APPROACHES FROM THE SOUTHWEST. FREQUENT GALE
GUSTS APPEAR LIKELY OVER FAR WEST...SO HAVE ISSUED A GALE WATCH.
WINDS OVER THE REST OF THE LAKE WILL STAY AT OR BLO 30 KTS. WINDS
DIMINISH LATER MONDAY NIGHT AND THEN SWITCH TO THE WEST TO 20-25 KTS
ON TUESDAY. LOW SLOWLY SLIDES TO THE NORTHEAST OF LK SUPERIOR REST
OF THE WEEK...RESULTING IN NORTHWEST WINDS MAINLY STAYING BLO 20 KTS.
&&
.HYDROLOGY...
ISSUED AT 454 AM EDT SUN MAY 11 2014
HIGHS MOSTLY IN THE 60S TODAY WILL RESULT IN ADDITIONAL SNOWMELT
OVER HIGHER TERRAIN OF NORTHERN UPR MICHIGAN. MINIMAL RAIN AMOUNTS
ARE EXPECTED THROUGH MUCH OF TONIGHT...BUT THEN RAIN CHANCES INCREASE
MONDAY/MONDAY NIGHT AND INTO TUESDAY MORNING. THERE IS A POTENTIAL
FOR MODERATE TO HEAVY RAIN OVER THE AREAS THAT ARE STILL MELTING
SNOW...SO THE RECENT HIGHER RIVER LEVELS WILL CONTINUE THROUGH MUCH
OF THE UPCOMING WEEK. THE FLOOD WARNING CONTINUES FOR THE STURGEON
RIVER NEAR CHASSELL...WHILE ADVISORIES ARE IN PLACE FOR THE STURGEON
RIVER NEAR ALSTON...AND THE MICHIGAMME RIVER NEAR WITCH LAKE AND
ALSO NEAR REPUBLIC. IF HEAVIER RAINS MATERIALIZE EARLY THIS WEEK...
ADDITIONAL ADVISORIES AND WARNINGS MAY BE NEEDED. THOSE LIVING NEAR
RIVERS...CREEKS...AND STREAMS SHOULD CONTINUE TO MONITOR THE LATEST
RIVER LEVELS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WATCH FROM MONDAY MORNING THROUGH MONDAY EVENING FOR LSZ162.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...VOSS
MARINE...JLA
HYDROLOGY...JLA
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
135 PM EDT SUN MAY 11 2014
LATEST UPDATE...
AVIATION
.SYNOPSIS...
ISSUED AT 328 AM EDT SUN MAY 11 2014
HIGH PRESSURE WILL SLIP EAST AND ALLOW A FRONTAL SYSTEM TO MOVE
BACK INTO THE AREA TONIGHT. AS THIS SYSTEM MOVES BACK IN SHOWERS
AND THUNDERSTORMS WILL BECOME MORE LIKELY THIS EVENING INTO
TUESDAY EVENING. WARMER AIR WILL MOVE INTO THE AREA FOR THE FIRST
COUPLE OF DAYS OF THE NEW WORK WEEK BEFORE COLDER AIR MOVES IN
BEHIND THE SYSTEM FOR LATE IN THE WEEK.
&&
.UPDATE...
ISSUED AT 1047 AM EDT SUN MAY 11 2014
WILL ISSUE A FCST UPDATE TO LOWER/DELAY THE CHANCE OF RAIN TODAY
AND TO BE MORE OPTIMISTIC WITH CLOUD COVER BASED ON CURRENT
SATELLITE/RADAR TRENDS AS WELL AS LATEST HRRR GUIDANCE. WILL ONLY
CARRY A 20 POP AFTER 5 PM SOUTH OF I-96 WHERE LEADING EDGE OF
BETTER MOISTURE/INSTABILITY WILL BE NOSING IN LATER IN THE DAY.
NEW 12Z NAM SHOWS LLJ FOCUSING FARTHER WEST TONIGHT AND AIMED INTO
IOWA/SRN MN/SW WI. MAY HAVE TO CONSIDER LOWERING POPS TONIGHT AS
WELL BUT WILL WAIT ON ADDITIONAL GUIDANCE.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 328 AM EDT SUN MAY 11 2014
MAIN FOCUS OF THE SHORT TERM CONTINUES TO BE CONVECTIVE TRENDS AND
SEVERE WEATHER POTENTIAL THROUGH THE PERIOD. THERE ARE NO REAL
CHANGES TO THE FCST.
THE QUIETEST PERIOD OF THE SHORT TERM WILL BE THE FIRST PERIOD
TODAY. THE CWFA REMAINS DRY AS OF 07Z THIS MORNING...HOWEVER WE ARE
EXPECTING AT LEAST A FEW LIGHT SHOWERS TO DEVELOP AND ROLL IN LATER
THIS MORNING AND THIS AFTERNOON. THIS WILL OCCUR AS A LLJ OF 35+
KNOTS FUELING A FEW SHOWERS AN ISOLATED THUNDER NEAR THE QUAD CITIES
WILL TRANSLATE EAST THROUGH 18Z. THIS LLJ WILL BE WEAKENING AND WILL
BE BATTLING A FAIR AMOUNT OF DRY AIR INITIALLY OVER THE AREA.
WE WILL SEE A BETTER POTENTIAL OF STORMS DEVELOP THIS EVENING ACROSS
THE SOUTH...AND EVENTUALLY THE CHCS WILL SPREAD NORTH THROUGH THE
NIGHT TONIGHT. A STALLED OUT FRONT CURRENTLY ACROSS IL/IN/OH WILL
STRENGTHEN THIS EVENING AS BETTER WARMTH AND MOISTURE ADVECTS NORTH
OUT OF THE GULF OF MEXICO. WE WILL SEE ANOTHER LLJ INCREASE TO
AROUND 30-35 KNOTS AND NOSE UP INTO THE HEART OF THE CWFA. THE
STORMS SHOULD START OUT AS MAINLY ELEVATED WITH THE FRONT TO OUR
SOUTH INITIALLY. FCST SOUNDINGS SHOW THAT HAIL LOOKS LIKE THE BEST
THREAT WITH A GOOD DEAL OF CAPE IN THE -10C TO -30C LAYER. DAMAGING
WINDS ARE POSSIBLE...HOWEVER A BIT LIMITED DUE TO THE ELEVATED
NATURE OF THE STORMS.
WE EXPECT THAT WAVES OF STORMS WILL REMAIN POSSIBLE THROUGH MON AND
INTO MON EVENING. THE FRONT IS EXPECTED TO GET HELD UP GENERALLY
AROUND THE I-96 CORRIDOR AS IT WILL WAIT FOR A GOOD PUSH IN THE MID
LEVELS AS THE WRN TROUGH STARTS TO LIFT OUT. A 25-30 KNOT LLJ WILL
GENERALLY REMAIN IN PLACE THROUGH THAT PERIOD WHICH WILL HELP TO
FEED THE FORCING AND MOISTURE/WARMTH INTO THE AREA. IT LOOKS LIKE
ALONG OR JUST NORTH OF THE I-96 CORRIDOR WILL SEE THE HIGHEST RAIN
AMOUNTS. WHAT WILL BE INTERESTING IS THE POTENTIAL OF SOME SFC BASED
INSTABILITY ON MON SOUTH OF THE FRONT. THIS COULD ENHANCE THE THREAT
OF SOME SEVERE WX ALONG WITH DEEP LAYER SHEAR VALUES AT OR ABOVE
30.
WE SHOULD SEE A BREAK IN THE MORE WIDESPREAD SHOWER AND STORM
ACTIVITY THEN FOR THE SECOND HALF OF MON NIGHT. WE FINALLY SEE THE
TROUGH OUT WEST DIG ENOUGH THAT THE RIDGE BUILDS IN OUR
NEIGHBORHOOD. THIS WILL PUSH THE WARM FRONT WELL NORTH OF THE AREA
BY TUE.
SHOWERS AND STORMS BECOME MORE NUMEROUS ON TUE ONCE AGAIN AS THE
COLD FRONT AND WHAT LOOKS LIKE A THERMAL TROUGH DEVELOPS INLAND
AND BEGINS TO PUSH THROUGH THE AREA. WE PREFER THE SLOWER FOREIGN
MODEL SOLUTIONS AS THE FRONT LOOKS TO BE FAIRLY PARALLEL WITH THE
UPPER JET. THIS WOULD BRING THE FRONT THROUGH DURING THE DAY WHEN
SOME DIURNAL INSTABILITY WILL BE POSSIBLE. DEEP LAYER SHEAR WILL
ONCE AGAIN BE SUFFICIENT FOR ORGANIZED STORMS WITH VALUES OVER 30
AND INCREASING THAT DAY. FCST SOUNDINGS DO LOOK QUITE CLOUDY WITH A
LOT OF MOISTURE...WHICH WOULD LIMIT THE SEVERE POTENTIAL.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 328 AM EDT SUN MAY 11 2014
LOOKS LIKE A PRETTY UNSETTLED PERIOD WITH COLD AND SHOWERY WEATHER
BY THE END OF THE WEEK UNDER AN UPPER LOW. WILL HAVE TO WATCH
CLOSELY FOR ANY CLEARING OUT ON THURSDAY NIGHT OR FRIDAY NIGHT WHICH
WOULD RESULT IN WIDESPREAD FROST/FREEZE CONDITIONS GIVEN HOW COLD IT
WILL BE.
COLD FRONT PUSHES EAST TUESDAY NIGHT. MODEL DIFFERENCES BETWEEN THE
00Z RUNS OF THE GFS AND ECMWF ARE THE SAME AS THEY HAVE BEEN THE
LAST FEW DAYS WITH THE ECMWF HAVING A SFC LOW FORM ON THE SLOW
MOVING FRONT WHICH BRINGS ANOTHER ROUND OF RAIN FOR WEDNESDAY NIGHT
AND THURSDAY...WHILE THE GFS IS FASTER WITH THE FRONT AND
CORRESPONDINGLY FURTHER EAST WITH THE RAIN. EVEN SO...IT CONTINUES
TO BRING THE CHANCE FOR SHOWERS BY THURSDAY AS SHARP UPPER TROUGH
GOES NEGATIVE TILT THEN CUTS OFF.
UPPER LOW THEN PERSISTS OVER THE CENTRAL GREAT LAKES INTO THE
WEEKEND AND 850 MB TEMPS ARE DOWN TO MINUS 2C TO MINUS 4C ACROSS THE
NORTHERN FORECAST AREA. COULD SEE SOME WET SNOW OR GRAUPEL IN ANY
SHOWERS/CONVECTIVE UPDRAFTS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 135 PM EDT SUN MAY 11 2014
BEST MOISTURE AND INSTABILITY HAS BEEN DELAYED INTO SW MI.
THEREFORE THE 18Z TAFS REFLECT A SLOWER ARRIVAL OF ANY STORMS TO
AFTER 04Z. UNTIL THEN EXPECT VFR CONDITIONS WITH SOUTH WINDS AROUND
10 KNOTS.
THE STORMS OVERNIGHT SHOULD REMAIN SCATTERED SO HAVE ONLY INCLUDED
VICINITY THUNDER AT THIS POINT. THE MAIN FOCUS TO THE STORMS
SHOULD BE ALONG I-94...BUT THERE COULD ALSO BE A FEW AROUND
I-96...ESPECIALLY AROUND DAYBREAK. MOSTLY VFR CONDITIONS CAN BE
EXPECT OUTSIDE OF AN STORMS THROUGH MID DAY MONDAY.
&&
.MARINE...
ISSUED AT 328 AM EDT SUN MAY 11 2014
WE CONTINUE TO EXPECT THAT WINDS WILL INCREASE OVERNIGHT
TONIGHT AS THE NEXT SYSTEM COMES IN...AND COULD BE EXCEEDING
SMALL CRAFT ADVISORY CRITERIA BY DAYBREAK MONDAY MORNING. THIS IS
NOT A GUARANTEE HOWEVER AS WE WILL HAVE A STABLE SITUATION WHERE
WARMER AIR IS MOVING IN OVER COLDER WATER. THIS POTENTIAL WINDY
PERIOD WOULD LAST INTO TUESDAY MORNING BEFORE CONDITIONS WOULD
IMPROVE A BIT AS A WEAKER GRADIENT MOVES IN WITH THE FRONT.
ANOTHER BURST OF WIND WILL BE POSSIBLE BEHIND THE FRONT TUE EVENING.
&&
.HYDROLOGY...
ISSUED AT 328 AM EDT SUN MAY 11 2014
HYDRO CONCERNS WILL LIKELY RAMP UP BEGINNING SUNDAY AND LASTING INTO
MID WEEK AT LEAST. AN ACTIVE PERIOD IS EXPECTED TO DEVELOP FOR
THE SUNDAY THROUGH TUESDAY TIME FRAME WITH HEAVY RAINS POSSIBLE.
THE BOUNDARY THAT WENT THROUGH THE AREA FRIDAY EVENING WILL COME
BACK NORTH AS A WARM FRONT ON SUNDAY...PULLING GULF MOISTURE WITH
IT. PWAT VALUES RISE TO SLIGHTLY ABOVE 1.50 INCHES...WHICH WOULD
BE 99TH PERCENTILE TYPE OF AMOUNTS.
THE WETTEST PERIOD LOOKS TO COME FROM SUNDAY NIGHT THROUGH
TUESDAY. RAINFALL AMOUNTS OF 1 TO 2 INCHES LOOKS QUITE
POSSIBLE...WITH SOME LOCALLY HEAVIER AMOUNTS LIKELY. SOME RIVERS
UP NORTH ARE ALREADY ABOVE ADVISORY STAGE AND OBVIOUSLY ABOVE
NORMAL. ADDITIONAL RAINFALL WOULD ONLY PUSH STAGES HIGHER. AT THIS
POINT NOT CONSIDERING ANY HYDRO HEADLINES. WE WILL CONTINUE TO
MONITOR.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
UPDATE...MEADE
SYNOPSIS...NJJ
SHORT TERM...NJJ
LONG TERM...OSTUNO
AVIATION...JK
HYDROLOGY...DUKE/NJJ
MARINE...NJJ
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
354 PM CDT SUN MAY 11 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 355 PM CDT SUN MAY 11 2014
EARLY AFTERNOON WATER VAPOR IMAGERY TOGETHER WITH RAP 500MB HEIGHTS
AND WINDS IDENTIFIED A VIGOROUS SHORTWAVE ROTATING OVER THE
4-CORNERS REGION...WITH AN MCS ONGOING IN EASTERN IA. VISIBLE
SATELLITE SHOWED CLEARING BEHIND THIS MCS...AND THE SURFACE OBS HAVE
ALREADY REFLECTED THE BOUNDARY LAYER DESTABILIZATION AS TEMPERATURES
HAVE INCREASED 5DEG/HR BUT KEPT THE EASTERLY COMPONENT IN THE WIND
FIELD.
THIS WIND SHIFT MARKED THE STOUT FRONTAL BOUNDARY WHICH WILL
BE THE FOCUS FOR TORNADOES LATER THIS AFTERNOON ACROSS EASTERN NE
AND WESTERN IA. TEMPERATURES WERE IN THE MID 80S SOUTH OF THIS WARM
FRONT WITH SOUTHERLY WINDS...WHILE NORTH OF THE WARM FRONT
TEMPERATURES WERE IN THE LOW TO MID 70S WITH DEWPOINTS IN THE MID
60S. THE MLCAPE GRADIENT MIRRORED THE POSITION OF THE EAST/WEST
ORIENTED WARM FRONT...BUT INSTABILITY WAS BUILDING WELL NORTH OF THE
FRONT AS EVIDENT BY THE 3HR SBCAPE CHANGE ON THE SPC MESOANALYSIS
PAGE. THE FINAL POSITION OF THE WARM FRONT WILL DICTATE WHERE THE
SURFACE BASED STORMS ARE...AND THUS THE BEST THREAT FOR TORNADOES.
AT THIS TIME IT APPEARS THAT THE THREAT WILL REMAIN WELL SOUTH OF
THE CWA.
HOWEVER...THE LAST FEW RUNS OF THE HRRR AND HOPWRF INDICATE THAT A
FEW ELEVATED STORMS ARE EXPECTED AFTER 00Z ACROSS THE SOUTHERN PART
OF THE FORECAST AREA. THESE STORMS WILL HAVE 1000-1500J/KG OF MUCAPE
TO WORK WITH DEEP SHEAR FAVORABLE FOR ORGANIZED CONVECTION. A FEW
STORMS WILL HAVE THE POTENTIAL FOR PRODUCE SEVERE HAIL...MAINLY
ALONG THE I-90 CORRIDOR. HEAVY RAIN IS ALSO A THREAT...PERHAPS
MORESO THAN THE SEVERE WEATHER. AT THIS TIME...IT APPEARS THAT THE
HEAVIEST RAINFALL WILL FALL JUST SOUTH AND EAST OF THE FORECAST AREA
ALONG A LINE FROM OMAHA TO LA CROSSE WI. IT IS WITHIN THIS LINE THAT
A HP SUPERCELLS ARE EXPECTED WHICH WILL BE CAPABLE OF PRODUCING
2-3IN/HR RAINFALL RATES AND FLASH FLOODING GIVEN THE RAINFALL THAT
OCCURRED EARLIER THIS MORNING. IN OUR CWA...WE DID NOT HAVE
THE MORNING RAINFALL...AND SUPERCELLS APPEAR LESS LIKELY...SO
ALTHOUGH WE MAY GET A QUICK 1-2 INCHES OF RAIN WITH A FEW OF THE
HEAVIER CELLS...THIS IS ABOVE FLASH FLOOD GUIDANCE. THEREFORE HAVE
OPTED TO HOLD OFF ON A FLOOD WATCH FOR NOW. TO TIE BACK INTO THE
HIRES MODELS...THE PROGRESSIVE NATURE OF THE EASTWARD MOVING STORMS
ALSO SUPPORTS NOT ISSUING A FLOOD WATCH.
THERE WILL BE A LULL IN THE PRECIP ACROSS CENTRAL MN AS THE SURFACE
LOW TRACKS NORTHEASTWARD OVERNIGHT. MEANWHILE LIGHT RAIN WILL
CONTINUE ACROSS THE WESTERN CWA IN THE DEFORMATION AREA OF THE UPPER
LEVEL WAVE. FORECAST MODELS SHOW THE POTENTIAL FOR SOME CONVECTION
REDEVELOPING IN THE WARM SECTOR OF THE SURFACE LOW ACROSS EASTERN MN
AND WESTERN WI...SO TRIED TO REFLECT THAT IN THE AFTERNOON POP
GRIDS. THESE STORMS DO HAVE THE POTENTIAL TO BE SEVERE.
&&
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 355 PM CDT SUN MAY 11 2014
NOT MUCH IN THE WAY OF CHANGE TO THE EXTENDED PORTION OF THE
FORECAST...WITH THE UPCOMING WEEK BEING MARKED BY COOL TEMPERATURES
AND PERIODIC SCATTERED LIGHT SHOWERS AS A DEEPLY AMPLIFIED
LONGWAVE TROUGH PIVOTS ACROSS THE UPPER MIDWEST AND GREAT LAKES
REGIONS.
THE BEGINNING OF THE LONG TERM PERIOD /MONDAY NIGHT/ WILL FEATURE
RAIN SHOWERS WINDING DOWN AS THE LOW LIFTS TO LAKE SUPERIOR.
ADDITIONAL RAINFALL AMOUNTS SHOULD BE AROUND A COUPLE TENTHS OF AN
INCH OR LESS.
TUESDAY THROUGH FRIDAY BRINGS CYCLONIC FLOW WITH COOLER THAN
NORMAL TEMPERATURES AND THE POTENTIAL FOR OCCASIONAL SCATTERED
SHOWERS AS THE TROUGH BLANKETS THE REGION. HIGHS WILL BE IN THE
50S AND LOWS WILL DIP INTO THE LOWER 30S AND 40S. THE POTENTIAL
FOR FROST LOOKS TO BE TUESDAY THROUGH THURSDAY NIGHTS.
TEMPERATURES MODERATE NEXT WEEKEND AS WESTERN UPPER RIDGING BUILDS
INTO THE CENTRAL CONUS. HIGHS IN THE 60S LOOK LIKE A GOOD BET FOR
NEXT WEEKEND...ALTHOUGH A FEW SHOWERS MAY BE LURKING ON SUNDAY IF
THE ECMWF SOLUTION VERIFIES /WHICH INDICATES A TROUGH WILL BUST
IN FROM THE PACIFIC NORTHWEST AND BREAK DOWN THE RIDGE/.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 116 PM CDT SUN MAY 11 2014
MAIN ISSUE THE REST OF THIS AFTERNOON INTO EARLY EVENING WILL BE
SHOWERS TRYING TO MOVE FROM SD INTO MN. AIR IS QUITE DRY IN THE
LOWER AND MID LEVELS AND LATEST MODELS HAVE CAUGHT ON THIS WITH A
DELAY IN PRECIP. THUS HAVE INDICATED SUCH WITH THE TAFS. ELEVATED
INSTABILITY DOES NOT REALLY BECOME SIGNIFICANT UNTIL AROUND 02Z IN
FAR SOUTHERN MN...THEN CENTRAL MN AND WEST CENTRAL WISCONSIN UNTIL
06Z OR SO. THUS HAVE ALSO DELAYED MENTION OF THUNDER UNTIL MAINLY
THE LATE NIGHT HOURS. MOISTURE TRANSPORT AND LOW LEVEL JET LOOK
DECENT FOR SOUTH CENTRAL MN INTO WISCONSIN...WHERE RAIN SHOULD BE
HEAVIEST...WITH MORE OF A SCATTERED PRECIP PATTERN FARTHER TO THE
NW. OTHERWISE... MVFR CEILINGS GRADUALLY DEVELOP THIS EVENING...
AND ESPECIALLY LATE TONIGHT IN THE WAKE OF THE SHOWERS AND STORMS.
LOOKS LIKE IFR CEILINGS WILL BE WIDESPREAD MONDAY MORNING BEFORE
LIFTING TO MVFR MIDDAY.
KMSP...LIGHT WINDS HAVE BEEN FLOPPING AROUND DURING
MIDDAY...INCLUDING SSE NOW...BUT SHOULD SETTLE TO THE EAST FOR
THE MOST PART. A FEW SHOWERS MOVING IN THIS EVENING...BUT MAIN
THREAT FOR HEAVIER SHOWERS AND STORMS WILL BE LATE TONIGHT WHEN
EXCELLENT LOW LEVEL JET AND MOISTURE TRANSPORT TAKE AIM AT THE
AREA. THERE IS SOME CHANCE THE HEAVY RAIN WILL BYPASS KMSP TO THE
SOUTHEAST...BUT IT DOES LOOK LIKE MSP WILL GET SOME HEAVY RAIN AT
TIMES. AFTER THAT...SURFACE LOW LOOKS TO TRACK VERY CLOSE TO KMSP
TOMORROW MIDDAY...MEANING THAT WIND DIRECTION WILL BE QUITE
VARIABLE BUT SPEEDS WILL BE LIGHT. THIS ALSO MEANS CONFIDENCE IS
HIGH THAT MVFR CEILINGS WILL DEVELOP IN THE WAKE OF THE
PRECIP...WITH A VERY GOOD CHANCE FOR IFR.
/OUTLOOK FOR KMSP/
TUE...MVFR POSSIBLE. SLGT CHC -SHRA. WINDS W-NW 15-20 KTS.
WED...MVFR POSSIBLE. SLGT CHC -SHRA. WINDS W-NW 5-15 KTS.
THU...MVFR POSSIBLE. SLGT CHC -SHRA. WINDS NW 5-15 KTS.
&&
.HYDROLOGY...
ISSUED AT 355 PM CDT SUN MAY 11 2014
AT THIS TIME RIVER FLOODING APPEARS TO BE THE PRIMARY CONCERN
MAINLY IN WESTERN WI AND THE MAINSTEM OF THE MISSISSIPPI RIVER.
ANOTHER ROUND OF 1 TO 2 INCHES OF BASIN-WIDE RAINFALL IS EXPECTED
OVER THE NEXT 24 HRS. AT THIS TIME...THE THREAT FOR THE HEAVIEST
RAIN AND FLASH FLOODING APPEARS TO BE ACROSS IOWA...SO NOT
ANTICIPATING ANY FLASH FLOODING IN MN OR WI. IF IT WERE TO
HAPPEN...IT WOULD BE IN FAR SOUTHERN MN. LASTLY, IF THE FORECAST
RAINFALL AMOUNTS TREND HIGHER THAN CURRENTLY EXPECTED...THE
FLOODING POTENTIAL WILL INCREASE AS WELL.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...JRB
LONG TERM...LS
AVIATION...TDK
HYDROLOGY..JRB
AREA FORECAST DISCUSSION
NWS BISMARCK ND
116 PM CDT SUN MAY 11 2014
.UPDATE...
ISSUED AT 116 PM CDT SUN MAY 11 2014
LINGERING SHOWERS OVER THE NORTH CENTRAL CONTINUE TO LIFT NORTH
AND SHRINK IN AREAL COVERAGE. SHOWERS MOVING NORTH THROUGH SOUTH
DAKOTA WILL LIKELY NOT REACH THE FAR SOUTH UNTIL LATE AFTERNOON
AND HAVE TRIMMED BACK POPS OVER THE FAR SOUTH CENTRAL INTO THE
SOUTHERN JAMES RIVER VALLEY. CLOUDS HAD CLEARED OVER THE NORTHWEST
BRIEFLY BUT CUMULUS HAVE NOW FORMED. EXPECT A DECREASE IN
CUMULUS COVERAGE THROUGH THE REMAINDER OF THE AFTERNOON OVER THE
NORTHWEST AND FAR WEST CENTRAL. MOST AREAS REMAIN CLOUDY AND HAVE
CUT BACK ON HIGH TEMPERATURES ACCORDINGLY. MAINLY MID TO UPPER 40S
SOUTHWEST THROUGH NORTH CENTRAL...WITH A FEW 50S FAR SOUTHEAST AND
FAR NORTHWEST.
UPDATE ISSUED AT 1035 AM CDT SUN MAY 11 2014
WEAK UPPER LEVEL IMPULSE IS RESPONSIBLE FOR AN AREA OF SHOWERS
FROM MINOT AND MOHALL NORTHEAST THROUGH WESTHOPE AND BOTTINEAU.
THE AREA HAS MOVED LITTLE THE PAST FEW HOURS...BUT CONTINUES TO
SHRINK IN AREAL COVERAGE. WILL KEEP HIGH POPS IN THIS AREA THROUGH
THE MORNING WITH DECREASING POPS BY EARLY AFTERNOON. ANOTHER AREA
OF SHOWERS ASSOCIATED WITH A CENTRAL PLAINS STORM SYSTEM CONTINUES
TO LIFT NORTH TOWARD SOUTHERN NORTH DAKOTA. HOWEVER...PROGRESS HAS
SLOWED AND WILL REMOVE MENTION OF PRECIPITATION THIS MORNING OVER
THE FAR SOUTH CENTRAL INTO THE JAMES RIVER BASIN...WITH INCREASING
POPS DURING THE AFTERNOON.
RAISED SKY COVER MOST AREAS THIS MORNING...KEEPING OVERCAST SKIES
CENTRAL AND SOUTHWEST THROUGH THE DAY. ALSO RAISED WINDS TODAY
CENTRAL AND SOUTHWEST. LATEST 13 UTC RAP INDICATES 25-30 KNOT
WINDS POTENTIALLY WORKING DOWN TO THE SURFACE THIS AFTERNOON. THIS
WOULD BE NEAR ADVISORY CRITERIA. WILL MONITOR WINDS BUT HOLD OFF
ON ANY ADVISORY FOR NOW.
UPDATE ISSUED AT 654 AM CDT SUN MAY 11 2014
UPDATED THE FORECAST TO INCREASE MORNING POPS OVER NORTH CENTRAL
NORTH DAKOTA WHERE THE LATEST RADAR/SURFACE OBS INDICATED ONGOING
RAIN SHOWER ACTIVITY. ALSO DECREASED POPS SOUTHWEST BASED ON
LATEST RADAR TRENDS. THE LATEST HRRR PROGS RAIN SHOWER ACTIVITY
OVER NORTHERN NORTH DAKOTA TO DIMINISH THIS AFTERNOON WITH RAIN
SHOWERS DEVELOPING OVER THE SOUTHERN JAMES RIVER BASIN THIS
AFTERNOON. GENERALLY FOLLOWED THE HRRR PROG WITH RESPECT TO POP
TRENDS TODAY. OTHERWISE...THE REMAINING WEATHER ELEMENTS ARE IN
GOOD SHAPE. THE UPDATED PRODUCTS HAVE BEEN SENT.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 350 AM CDT SUN MAY 11 2014
THE FOCUS IN THE SHORT TERM IS ON THE PROGRESSION OF PRECIPITATION
THROUGH TONIGHT.
LATEST REFLECTIVITY SHOWS THE MAJORITY OF PRECIPITATION OVER NORTH
CENTRAL NORTH DAKOTA. THE 00 UTC WRF AND LATEST HRRR RUNS HAVE
VERIFIED PRETTY WELL WITH CURRENT OBSERVATIONS. ON THE OTHER HAND
THE 00 UTC RUNS OF THE GFS...NAM...ECMWF...AND NHEM GEM HAD A
DIFFICULT TIME NAILING DOWN THE PRECIPITATION OVER THE NORTH CENTRAL
AND ALL OVERPLAYED THE WRAP AROUND PRECIPITATION LOCATED OVER
EASTERN MONTANA AND WESTERN NORTH DAKOTA. WITH THAT SAID USED THE
HRRR AND 00 UTC WRF RUN FOR POPS THROUGH 12 UTC SUNDAY THEN A MODEL
BLEND FROM 12 UTC SUNDAY THROUGH 12 UTC MONDAY SINCE MODEL AGREEMENT
WAS GOOD ON THE WEST TO EAST PROGRESSION OF PRECIPITATION THROUGH SUNDAY.
AT THIS TIME NO THUNDERSTORM ACTIVITY IS EXPECTED SUNDAY...JUST A
CHILLY RAW DAY. WINDS WILL ALSO BE BREEZY 15 TO 25 MPH FROM THE
NORTHWEST SUSTAINED ACROSS THE WEST AND CENTRAL. NO WIND ADVISORY IS
ANTICIPATED AT THIS TIME.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 350 AM CDT SUN MAY 11 2014
THE 00Z GFS/GEM/ECMWF PROG AN OPEN WAVE TO MEANDER OVER
SOUTHEASTERN SASKATCHEWAN/WESTERN NORTH DAKOTA MONDAY. THIS WILL
LEAD TO ENHANCED PRECIPITATION CHANCES EAST OF HIGHWAY 83...MAINLY
OVER THE JAMES RIVER BASIN. THE OPEN WAVE IS THEN PROGGED TO
SLOWLY MEANDER EAST...SHIFTING PRECIPITATION CHANCES EAST ALONG
WITH IT. SOME WRAP AROUND MOISTURE WILL GENERATE A SLIGHT CHANCE
OF SHOWERS OVER WESTERN AND CENTRAL NORTH DAKOTA LATE TUESDAY.
HOWEVER...RAINFALL AMOUNTS SHOULD BE VERY LIGHT IF ANY RAIN WERE
TO DEVELOP.
BY WEDNESDAY AND THURSDAY...SYNOPTIC SUBSIDENCE IS PROGGED TO
OVERSPREAD THE STATE AHEAD OF A DEVELOPING PACIFIC RIDGE. THIS
SHOULD LEAD TO MAINLY DRY CONDITIONS WITH HIGHS IN THE UPPER 50S.
THE MEDIUM RANGE MODELS NOW PROG A WEAK WAVE TO TRAVERSE NORTH
DAKOTA FRIDAY/FRIDAY NIGHT. INDICATED SLIGHT CHANCE POPS AS A
RESULT. THE PACIFIC RIDGE IS THEN FORECAST TO TRANSLATE EAST INTO
THE GREAT PLAINS BY SATURDAY. IF THIS VERIFIES...IT SHOULD GENERATE
DRY CONDITIONS AND HIGHS IN THE MID 60S BY THE END OF THE PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 117 PM CDT SUN MAY 11 2014
MVFR CEILINGS CONTINUE AT KMOT...KDIK...KBIS AND KJMS. COULD SEE
PERIODS OF LOW VFR CEILINGS LATE THIS AFTERNOON. ANOTHER ROUND OF
RAIN IS EXPECTED TO LIFT INTO EASTERN NORTH DAKOTA LATE THIS
AFTERNOON AND TONIGHT. THIS WILL KEEP MVFR CEILINGS AT KJMS
THROUGH 18Z MONDAY. KBIS WILL LIKELY BE ON THE EDGE WITH CLEARING
SKIES TO THE WEST AND MVFR CEILINGS EAST. LEANED TOWARD
PESSIMISTIC SIDE FOR NOW WITH MVFR CEILINGS THROUGH 14Z MONDAY.
KDIK AND KMOT WILL SEE A MUCH HIGHER PROBABILITY OF VFR CEILINGS
ONCE THE CEILINGS LIFT TO VFR TODAY AS DRIER AIR WILL MOVE INTO
THESE AREAS. KISN WILL REMAIN VFR THROUGH THE TAF PERIOD. MODERATE
NORTH TO NORTHWEST WINDS WILL CONTINUE THROUGH THE
PERIOD...INCREASING TO 20 TO 35 MPH MONDAY MORNING.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...TWH
SHORT TERM...MM
LONG TERM...TM
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
645 PM EDT SUN MAY 11 2014
.SYNOPSIS...
A WARM FRONT WILL LIFT NORTH ACROSS THE AREA TONIGHT AS LOW PRESSURE
OVER THE PLAINS TRACKS NORTHEAST INTO THE UPPER MIDWEST. THE LOW
WILL CONTINUE NORTHEAST INTO ONTARIO ON TUESDAY. A SLOW MOVING COLD
FRONT EXTENDING FROM THIS SYSTEM WILL MOVE EAST ACROSS THE AREA
TUESDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
THUNDERSTORM AND SHOWER ACTIVITY OVER LIMA OHIO AREA IS BEHAVING
ITSELF LIKE IT SHOULD BASED ON THE LATEST STORM PREDICTION CENTER
CONVECTIVE ANALYSIS. ACTIVITY DEVELOPS OVER RESIDUAL OUTFLOW
BOUNDARIES AND THEN TRIES TO MOVE NORTHEAST ONLY TO WEAKEN AS IT
MOVES INTO OUR SOUTHWEST AREA.
THIS ACTIVITY IS DIURNAL IN NATURE AND WILL LIKELY WEAKEN AS IT
MOVES NORTHEAST AND THE SUN SETS THIS EVENING.
LATEST SATELLITE AND HRRR MODEL INDICATES CONVECTION OVER IOWA
WILL CONTINUE TO MOVE EAST THIS EVENING INTO OUR WESTERN PORTIONS
BY 03Z THIS EVENING. STILL REMAINS TO BE SEEN IF THE INSTABILITY
WILL REMAIN STRONG ENOUGH TO SUPPORT THE ONGOING THUNDERSTORM
ACTIVITY. WILL BE MONITORING THIS THROUGH THE EVENING HOURS.
ONLY NEEDED TO MAKE SOME MINOR ADJUSTMENTS TO HOURLY TEMPERATURES
TO REFLECT THE CURRENT TEMPERATURES.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY NIGHT/...
ACTIVE WEATHER EXPECTED DURING THE FIRST PART OF THE WEEK AS THE
UPPER LEVEL TROUGH OVER THE PLAINS ADVANCES EASTWARD. THUNDERSTORM
FORECAST CONTINUES TO BE A CHALLENGE AND WILL BE DEPENDENT ON
PLACEMENT OF THE WARM FRONT AND EVOLUTION OF OVERNIGHT CONVECTION.
THE WARM FRONT MAY STILL LINGER IN THE EASTERN PORTION OF THE CWA
DURING THE MORNING AND MAY PROVIDE ENOUGH OF A FOCUS FOR ADDITIONAL
SCATTERED SHOWERS AND THUNDERSTORMS. WILL TAPER POPS DOWN FROM SOUTH
TO NORTH FROM MONDAY AFTERNOON INTO MONDAY NIGHT AS THE ATMOSPHERE
WARMS ALOFT AND A CAP DEVELOPS. HIGHS WILL PEAK IN THE LOW 80S
BENEATH PARTLY SUNNY SKIES ON MONDAY.
THE LOW PRESSURE SYSTEM OVER THE UPPER GREAT LAKES WILL CONTINUE TO
TRACK NORTHEAST INTO ONTARIO THROUGHOUT THE DAY ON TUESDAY.
ASSOCIATED COLD FRONT WILL MOVE INTO NORTHWEST OHIO DURING THE LATE
AFTERNOON WITH SHOWERS AND THUNDERSTORMS SPREADING IN FROM THE WEST.
THE STORM PREDICTION CENTER HAS A SEE TEXT IN PLACE FOR THE
CENTRAL GREAT LAKES ON TUESDAY AS THIS FRONT APPROACHES.
SUFFICIENT INSTABILITY WITH SHEER INCREASING AS THE FRONT
APPROACHES TO HAVE TO KEEP AN EYE ON THUNDERSTORMS IN NW OHIO
DURING THE AFTERNOON AND EVENING. IT LOOKS LIKE THE BETTER FORCING
PASSES TO OUR NORTH ON TUESDAY NIGHT WITH INSTABILITY DIMINISHING
QUICKLY OVERNIGHT. DID TWEAK POPS DOWN A LITTLE BIT FOR THE
OVERNIGHT PERIOD...MAINLY IN THE SOUTH.
MODELS ARE NOW SHOWING A SECONDARY WAVE OF LOW PRESSURE DEVELOPING
ALONG THE GULF COAST AND LIFTING NORTHEAST ACROSS OHIO ON WEDNESDAY
AFTERNOON/WEDNESDAY NIGHT. WIDESPREAD RAIN IS EXPECTED WITH GOOD
UPPER LEVEL DIVERGENCE OVERHEAD AND STRONG UPWARD MOTION AS THE TROUGH
TRIES TO BECOME NEGATIVELY TILTED. RAISED POPS TO 70-80 PERCENT FOR
WEDNESDAY NIGHT. QPF COULD EXCEED AN INCH FOR PORTIONS OF THE AREA
WITH THIS SYSTEM.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
BACK TO BELOW NORMAL TEMPERATURES FOR THIS PERIOD. SOME RESIDUAL
SHOWERS LEFT OVER ON THE BACK SIDE OF THE FRONT ON THURSDAY. THEY
WILL GRADUALLY DECREASE FROM WEST TO EAST. AN UPPER TROF WILL MOVE
ACROSS THE REGION FROM FRIDAY THROUGH SUNDAY. THE BEST CHANCE FOR
SCATTERED SHOWERS WITH THIS TROF WILL BE FRIDAY THROUGH SATURDAY.
THE THREAT OF SHOWERS MAY LINGER IN THE EXTREME EAST ON SUNDAY. WENT
VERY CLOSE TO HPC GUIDANCE FOR THE TEMPERATURE FORECAST.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
A WARM FRONT JUST NORTH OF THE OHIO RIVER WILL BEGIN MOVING
NORTHWARD TONIGHT AND SHOULD BE NORTH OF THE AREA AROUND DAYBREAK
MONDAY. THIS SYSTEM WILL INCREASE THE CLOUD COVER AND BRING A
CHANCE OF SHOWERS AND THUNDERSTORMS TO THE FORECAST AREA TONIGHT
AND MONDAY.
I WILL USE A COMBINATION OF TSTMS AND VCTS IN THE TAF FORECAST
FOR TONIGHT AND MONDAY.
LOOK FOR THE REMNANTS FROM THE SYSTEM OVER IOWA AND ILLINOIS
TO MOVE ACROSS THE WESTERN PORTIONS OF OUR THE FORECAST AREA
OVERNIGHT AND EARLY MONDAY. ELSEWHERE SOME CLOUDS AND MVFR FOG
ARE POSSIBLE.
.OUTLOOK...NON VFR AT TIMES MONDAY THRU THURSDAY IN SHOWERS AND
THUNDERSTORMS.
&&
.MARINE...
NO SMALL CRAFT ADVISORIES ARE EXPECTED BUT IT COULD BE CLOSE...
MAINLY AFTER A COLD FRONTAL PASSAGE TUESDAY NIGHT INTO WEDNESDAY.
THE BEST CHANCE IS FOR SPECIAL MARINE WARNINGS TO BE ISSUED FOR
STRONG THUNDERSTORMS ON THE LAKE AT TIMES THROUGH TUESDAY NIGHT.
AFTER THAT THE GRADIENT SEEMS TO BE LIGHT AS A RIDGE WILL BE
DOMINATING THE WEATHER OVER MUCH OF THE GREAT LAKES REGION.
AN ONSHORE FLOW DEVELOPED IN THE WEAK GRADIENT THIS AFTERNOON WITH A
RIDGE OVER WESTERN NEW YORK AND PENNSYLVANIA. THIS RIDGE WILL MOVE
EAST TONIGHT AND THE FLOW ON THE LAKE WILL BE MAINLY SOUTH MONDAY
AND MONDAY NIGHT. THE FLOW ALOFT WILL BE MODERATE AND WARM...SO NOT
EXPECTING THE 20 KNOT WINDS TO REACH THE SURFACE OF THE LAKE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KEC
NEAR TERM...LOMBARDY
SHORT TERM...KEC
LONG TERM...KIELTYKA
AVIATION...BC
MARINE...KIELTYKA
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
630 PM EDT SUN MAY 11 2014
.SYNOPSIS...
A WARM FRONT WILL LIFT NORTH ACROSS THE AREA TONIGHT AS LOW PRESSURE
OVER THE PLAINS TRACKS NORTHEAST INTO THE UPPER MIDWEST. THE LOW
WILL CONTINUE NORTHEAST INTO ONTARIO ON TUESDAY. A SLOW MOVING COLD
FRONT EXTENDING FROM THIS SYSTEM WILL MOVE EAST ACROSS THE AREA
TUESDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
THUNDERSTORM AND SHOWER ACTIVITY OVER LIMA OHIO AREA IS BEHAVING
ITSELF LIKE IT SHOULD BASED ON THE LATEST STORM PREDICTION CENTER
CONVECTIVE ANALYSIS. ACTIVITY DEVELOPS OVER RESIDUAL OUTFLOW
BOUNDARIES AND THEN TRIES TO MOVE NORTHEAST ONLY TO WEAKEN AS IT
MOVES INTO OUR SOUTHWEST AREA.
THIS ACTIVITY IS DIURNAL IN NATURE AND WILL LIKELY WEAKEN AS IT
MOVES NORTHEAST AND THE SUN SETS THIS EVENING.
LATEST SATELLITE AND HRRR MODEL INDICATES CONVECTION OVER IOWA
WILL CONTINUE TO MOVE EAST THIS EVENING INTO OUR WESTERN PORTIONS
BY 03Z THIS EVENING. STILL REMAINS TO BE SEEN IF THE INSTABILITY
WILL REMAIN STRONG ENOUGH TO SUPPORT THE ONGOING THUNDERSTORM
ACTIVITY. WILL BE MONITORING THIS THROUGH THE EVENING HOURS.
ONLY NEEDED TO MAKE SOME MINOR ADJUSTMENTS TO HOURLY TEMPERATURES
TO REFLECT THE CURRENT TEMPERATURES.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY NIGHT/...
ACTIVE WEATHER EXPECTED DURING THE FIRST PART OF THE WEEK AS THE
UPPER LEVEL TROUGH OVER THE PLAINS ADVANCES EASTWARD. THUNDERSTORM
FORECAST CONTINUES TO BE A CHALLENGE AND WILL BE DEPENDENT ON
PLACEMENT OF THE WARM FRONT AND EVOLUTION OF OVERNIGHT CONVECTION.
THE WARM FRONT MAY STILL LINGER IN THE EASTERN PORTION OF THE CWA
DURING THE MORNING AND MAY PROVIDE ENOUGH OF A FOCUS FOR ADDITIONAL
SCATTERED SHOWERS AND THUNDERSTORMS. WILL TAPER POPS DOWN FROM SOUTH
TO NORTH FROM MONDAY AFTERNOON INTO MONDAY NIGHT AS THE ATMOSPHERE
WARMS ALOFT AND A CAP DEVELOPS. HIGHS WILL PEAK IN THE LOW 80S
BENEATH PARTLY SUNNY SKIES ON MONDAY.
THE LOW PRESSURE SYSTEM OVER THE UPPER GREAT LAKES WILL CONTINUE TO
TRACK NORTHEAST INTO ONTARIO THROUGHOUT THE DAY ON TUESDAY.
ASSOCIATED COLD FRONT WILL MOVE INTO NORTHWEST OHIO DURING THE LATE
AFTERNOON WITH SHOWERS AND THUNDERSTORMS SPREADING IN FROM THE WEST.
THE STORM PREDICTION CENTER HAS A SEE TEXT IN PLACE FOR THE
CENTRAL GREAT LAKES ON TUESDAY AS THIS FRONT APPROACHES.
SUFFICIENT INSTABILITY WITH SHEER INCREASING AS THE FRONT
APPROACHES TO HAVE TO KEEP AN EYE ON THUNDERSTORMS IN NW OHIO
DURING THE AFTERNOON AND EVENING. IT LOOKS LIKE THE BETTER FORCING
PASSES TO OUR NORTH ON TUESDAY NIGHT WITH INSTABILITY DIMINISHING
QUICKLY OVERNIGHT. DID TWEAK POPS DOWN A LITTLE BIT FOR THE
OVERNIGHT PERIOD...MAINLY IN THE SOUTH.
MODELS ARE NOW SHOWING A SECONDARY WAVE OF LOW PRESSURE DEVELOPING
ALONG THE GULF COAST AND LIFTING NORTHEAST ACROSS OHIO ON WEDNESDAY
AFTERNOON/WEDNESDAY NIGHT. WIDESPREAD RAIN IS EXPECTED WITH GOOD
UPPER LEVEL DIVERGENCE OVERHEAD AND STRONG UPWARD MOTION AS THE TROUGH
TRIES TO BECOME NEGATIVELY TILTED. RAISED POPS TO 70-80 PERCENT FOR
WEDNESDAY NIGHT. QPF COULD EXCEED AN INCH FOR PORTIONS OF THE AREA
WITH THIS SYSTEM.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
BACK TO BELOW NORMAL TEMPERATURES FOR THIS PERIOD. SOME RESIDUAL
SHOWERS LEFT OVER ON THE BACK SIDE OF THE FRONT ON THURSDAY. THEY
WILL GRADUALLY DECREASE FROM WEST TO EAST. AN UPPER TROF WILL MOVE
ACROSS THE REGION FROM FRIDAY THROUGH SUNDAY. THE BEST CHANCE FOR
SCATTERED SHOWERS WITH THIS TROF WILL BE FRIDAY THROUGH SATURDAY.
THE THREAT OF SHOWERS MAY LINGER IN THE EXTREME EAST ON SUNDAY. WENT
VERY CLOSE TO HPC GUIDANCE FOR THE TEMPERATURE FORECAST.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
A WARM FRONT IS OVER THE OHIO RIVER AND WILL BEGIN MOVING NORTH
TONIGHT AND SHOULD BE NORTH OF THE AREA AROUND DAYBREAK MONDAY.
PLENTY OF MID AND HIGH CLOUDS OVER MUCH OF NORTHERN OHIO EARLY
THIS AFTERNOON KEEPING THE TEMPERATURE DOWN. THE CONVECTIVE
TEMPERATURE IS IN THE UPPER 70S. THE TRIGGERS WILL BE THE WARM
FRONT AND A SHORT WAVE THAT WILL MOVE WEST TO EAST ACROSS THE
REGION IN THE MAINLY WESTERLY FLOW ALOFT. IT IS VERY DIFFICULT TO
DECIDE WHERE EXACTLY TO PLACE THE VCTS AND OR TEMPO THUNDER.
SOMEWHAT CONFIDENT LATE TONIGHT THAT THE REMNANT FROM THE SYSTEM
OVER IOWA MAY MOVE ACROSS THE EXTREME NORTHERN PORTION OF THE
FORECAST AREA. ELSEWHERE SOME CLOUDS AND MVFR FOG ARE EXPECTED.
TODAYS AFTERNOON LAKE BREEZE MAY STAY MAINLY NEAR THE LAKESHORE
WITH THE GRADIENT FAIRLY TIGHT AND INCREASING LOW LEVEL WINDS.
.OUTLOOK...NON VFR AT TIMES MONDAY THRU THURSDAY IN SHOWERS AND
THUNDERSTORMS.
&&
.MARINE...
NO SMALL CRAFT ADVISORIES ARE EXPECTED BUT IT COULD BE CLOSE...
MAINLY AFTER A COLD FRONTAL PASSAGE TUESDAY NIGHT INTO WEDNESDAY.
THE BEST CHANCE IS FOR SPECIAL MARINE WARNINGS TO BE ISSUED FOR
STRONG THUNDERSTORMS ON THE LAKE AT TIMES THROUGH TUESDAY NIGHT.
AFTER THAT THE GRADIENT SEEMS TO BE LIGHT AS A RIDGE WILL BE
DOMINATING THE WEATHER OVER MUCH OF THE GREAT LAKES REGION.
AN ONSHORE FLOW DEVELOPED IN THE WEAK GRADIENT THIS AFTERNOON WITH A
RIDGE OVER WESTERN NEW YORK AND PENNSYLVANIA. THIS RIDGE WILL MOVE
EAST TONIGHT AND THE FLOW ON THE LAKE WILL BE MAINLY SOUTH MONDAY
AND MONDAY NIGHT. THE FLOW ALOFT WILL BE MODERATE AND WARM...SO NOT
EXPECTING THE 20 KNOT WINDS TO REACH THE SURFACE OF THE LAKE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KEC
NEAR TERM...LOMBARDY
SHORT TERM...KEC
LONG TERM...KIELTYKA
AVIATION...KIELTYKA
MARINE...KIELTYKA
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
350 PM CDT SUN MAY 11 2014
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 347 PM CDT SUN MAY 11 2014
COMPLEX FORECAST CONTINUES THIS AFTERNOON INTO THE OVERNIGHT.
CURRENT ANALYSIS SHOWS SURFACE LOW PRESSURE OVER WESTERN KANSAS.
KIND OF A DUAL WARM FRONT SIGNATURE. WITH MAIN AND STRONGEST WARM
FRONT ACROSS FAR SOUTHERN NEBRASKA INTO SOUTHWEST IOWA...WHICH WAS
REINFORCED BY THE OVERNIGHT MCS. MODELS IN GOOD AGREEMENT WITH THE
POSITION OF THIS FRONT...AND ALL GUIDANCE SUGGESTS IT WILL ONLY
SLOWLY MOVE NORTH TODAY. THIS IS THE AREA...SOUTHEASTERN NEBRASKA
INTO SOUTHWESTERN IOWA...AT GREATEST RISK FOR SEVERE WEATHER AND
TORNADOES...AS HIGHLIGHTED BY THE SPC OUTLOOK. FURTHER NORTH WE HAVE
A SECONDARY WARM FRONT RUNNING FROM THE TRIPLE POINT OVER SOUTHERN
NEBRASKA...NORTHEAST TO JUST SOUTH OF STORM LAKE. MARGINAL SURFACE
INSTABILITY IS BEGINNING TO FORM IN THIS AREA...ALTHOUGH MOST OF IT
IS REMAINING SOUTH OF OUR CWA. ALSO LARGE SCALE LIFT INCREASING ON
THE NOSE OF A PV WAVE IS HELPING TO TRIGGER ELEVATED SHOWERS AND
THUNDERSTORMS ACROSS THE NORTHWEST HALF OF THE CWA. THESE SHOULD
STAY BELOW SEVERE LIMITS AND PUSH NORTH OF THE AREA BY THIS EVENING.
DAYTIME HEATING AND INCREASING FORCING HAS ALSO HELPED FIRE
CONVECTION ACROSS SOUTH CENTRAL NEBRASKA. THE STRONGEST SURFACE
BASED SUPERCELLS WILL LIKELY RIDE FROM NEAR THE SOUTHERN WARM FRONT
TO THE SECONDARY WARM FRONT...AND THUS STAY SOUTH OF OUR CWA.
ALTHOUGH WILL NEED TO WATCH AREAS FROM SIOUX CITY TO STORM LAKE. LOW
LEVELS REMAIN STABLE...BUT ENOUGH DESTABILIZATION IS POSSIBLE FOR
STORMS MOVING INTO THIS AREA TO TAP INTO THE NEAR SURFACE LAYER. IF
THIS HAPPENED AN ISOLATED TORNADO WOULD BE POSSIBLE. WHILE THIS
STILL SEEMS TO BE A LOW THREAT...IT IS NOT IMPOSSIBLE AND WILL NEED
TO MONITOR TRENDS. SEEMS MORE LIKELY THAT STORMS THAT FORM AND MOVE
INTO OUR CWA WILL STAY ELEVATED...BASED ABOVE THE LOW LEVEL STABLE
LAYER. DECENT ELEVATED INSTABILITY SHOULD INCREASE AND COULD MAKE IT
ALL THE WAY TO ALMOST THE JAMES RIVER. QUESTION IS HOW MUCH MOISTURE
WE CAN GET ADVECTED INTO THE CWA...WITH THE CONVECTION TO OUR SOUTH
HAMPERING THIS TO A DEGREE. SEEMS LIKE A GOOD BET THAT NORTHWEST
IOWA AND SOUTHWEST MINNESOTA WILL GET INTO THE ACTION...LESS CERTAIN
FURTHER NORTHWEST. WITH THE ELEVATED WARM FRONT WELL TO OUR
NORTH...EVEN PARCELS LIFTED FROM NEAR 750 MB SHOULD HAVE AROUND 40
KTS OF SHEAR TO WORK WITH. SO THOUGHT IS ELEVATED SUPERCELLS WILL BE
POSSIBLE IF WE CAN GET THE MOISTURE AND ELEVATED INSTABILITY INTO
THE AREA. MAIN THREAT WOULD BE LARGE HAIL WITH ANY STORM. AGAIN
HIGHEST SEVERE THREAT SHOULD BE ACROSS NORTHWEST IOWA AND ADJACENT
AREAS OF SOUTHWEST MINNESOTA WHERE CONFIDENCE IS HIGHEST ON
INSTABILITY...THREAT IS MORE CONDITIONAL TOWARDS INTERSTATE 29. DO
LIKE THE HRRR IDEA OF PUSHING EVERYTHING EAST BY LATER THIS EVENING
AS STORMS ORGANIZE AND HELP PUSH THE FRONT EATS OF THE CWA. STILL
COULD BE SOME SCATTERED SHOWERS...BUT MOST OF THE OVERNIGHT MAY END
UP FREE OF HEAVY RAIN.
ANOTHER PUSH OF THETAE ADVECTION LATE TONIGHT INTO EARLY MONDAY AS
THE WHOLE SYSTEM BEGINS MOVING NORTHEAST. PRETTY GOOD LARGE SCALE
LIFT TOO AS A STRONG JET ROUNDS THE BASE OF THE TROUGH. THUS
THINKING PRECIPITATION COVERAGE WILL RAPIDLY INCREASE LATER TONIGHT
INTO TOMORROW. MOST OF THIS WEST OF THE JAMES RIVER WILL BE MORE
STABLE SHOWERY PRECIPITATION. DOES LOOK LIKE ELEVATED INSTABILITY
WILL REMAIN TO THE EAST...THUS SHOULD GET SOME THUNDER OUT OF THE
ACTIVITY. MAYBE EVEN SOME MARGINALLY SEVERE HAIL LATE TONIGHT INTO
MONDAY MORNING GIVEN THE WIND PROFILES IF ENOUGH INSTABILITY IS
PRESENT. ANY SURFACE BASED SEVERE WEATHER SHOULD STAY EAST OF THE
CWA. SO OVERALL MONDAY LOOKS LIKE A PRETTY WET DAY WITH HIGHS IN THE
40S AND 50S. WINDS WILL BE ON THE INCREASE AS WELL...WITH AROUND 35
KTS AT 925 MB. WILL BE VERY CLOSE TO WIND ADVISORY CRITERIA ALONG
AND WETS OF THE JAMES RIVER...WITH GUSTS APPROACHING 40 KTS. GIVEN
EXPECTED WEAK MIXING DUE TO THE RAIN AND MARGINAL WINDS ALOFT...WILL
HOLD OFF ON AN ADVISORY FOR NOW.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 347 PM CDT SUN MAY 11 2014
IN THE LONGER TERM...THE WEATHER IS HIGHLIGHTED BY MUCH BELOW
NORMAL TEMPERATURES FOR A BULK OF THE UPCOMING WEEK. FOR MONDAY
NIGHT...DECIDED TO RAISE POPS TO A LOW END LIKELY CATEGORY IN SOME
OF OUR WESTERN ZONES. ALTHOUGH THE GFS IS DRY BY MONDAY EVENING...
THE HIGHER RESOLUTION MODELS DO HANG BACK DEEPER RESIDUAL MOISTURE
IN OUR FORECAST AREA...ESPECIALLY FOR LOCATIONS WEST OF I 29. IN
ADDITION...BOTH THE NAM AND GFS SHOW TROWALING MONDAY EVENING IN
THE 305-315K LAYER. STILL...RAINFALL WILL BE LIGHT EVEN IN OUR
WESTERN ZONES...WITH OUR EASTERN ZONES NOT SEEING MUCH OF A
RAINFALL POTENTIAL. ALTHOUGH COOL...THE CLOUD COVER AND WIND WILL
HELP OUR LOWS FROM PLUMMETING TOO FAR MONDAY NIGHT WITH READINGS
MOSTLY A COUPLE OF DEGREES EITHER SIDE OF 40.
THEN THE UPPER LOW BEGINS TO MEANDER ACROSS SOUTHERN CANADA AND
THE NORTHERN MS VALLEY ALL THE WAY FROM TUESDAY THROUGH THURSDAY...
EVENTUALLY LIFTING INTO THE WESTERN GREAT LAKES BY FRIDAY.
THEREFORE VERY CHILLY WEATHER FOR THIS TIME OF YEAR WILL FOLLOW
SUIT. EVEN THE BIAS CORRECTED TEMPERATURES ARE NOW COLD...AND THEY
HAVE BEEN THE BEST RECENTLY IN OUR FORECAST AREA IN CAPTURING WARM...
MIXED OUT TEMPERATURES DURING THE DAYTIME. INSTABILITY CU WILL
POP ON TUESDAY WITH A STRONG UPPER CYCLONIC FLOW EXISTING...WITH A
SMALL CHANCE FOR LIGHT SHOWERS AROUND BROOKINGS AND SOUTHWEST MN.
AFTER SUNSET...SKIES WILL CLEAR TUESDAY NIGHT FOLLOWED BY SOME
MORE INSTABILITY DAYTIME CU ON WEDNESDAY...AND THERE ARE STRONG
INDICATIONS THAT A SHORT WAVE WILL DIVE DOWN THE NORTHWEST FLOW
ALOFT GIVING THE POSSIBILITY OF MORE WIDELY SCATTERED LIGHT
SHOWERS ACROSS THE ENTIRE FORECAST AREA. BUT LOW POPS ARE STILL
WARRANTED AS A QUESTION EXISTS AS TO HOW MUCH OF THIS RAINFALL
WILL ACTUALLY MEASURE. ULTIMATELY...THIS SHORT WAVE WILL REINFORCE
THE PARENT UPPER LOW AND KEEP OUR CYCLONIC FLOW GOING WITH A FEW
SHOWERS AGAIN POSSIBLE ON THURSDAY.
AS MENTIONED ABOVE...TUESDAY THROUGH THURSDAY WILL BE COLD WITH
HIGHS ONLY IN THE 50S TO AROUND 60. FURTHERMORE...MIXED LAYER
WINDS ARE STOUT ON TUESDAY PROMISING BREEZY CONDITIONS...LESS SO
ON WEDNESDAY BUT STILL THE WIND WILL BE STRONG ENOUGH TO GIVE A
RATHER RAW DAY.
ONE THING TO WATCH FOR BOTH TUESDAY NIGHT AND WEDNESDAY NIGHT AS
SKIES CLEAR AFTER SUNSET AND WINDS SUBSIDE...IS THE POSSIBILITY OF
FROST HERE AND THERE. DID NOT PUT THEM IN THE GRIDS YET...AND
CERTAINLY DID NOT ISSUE ANY FROST HEADLINES. BUT SOME OF OUR LOWS
DO FALL INTO THE MID 30S SO WOULD NOT BE SURPRISED TO SEE SOME
LIGHT FROST IN LOW LYING AREAS.
FURTHER OUT FRIDAY THROUGH SUNDAY...THE UPPER LOW FINALLY MOVES
INTO THE GREAT LAKES...THE NORTH OF THE GREAT LAKES ALLOWING THE
FLOW TO BECOME QUASI ZONAL. THERE MAY BE SOME WARM AIR ADVECTION
SHOWERS ON SUNDAY AS THE NEXT UPPER TROUGH BEGINS TO DIG DOWN THE
WESTERN U.S. COAST. THEREFORE HIGHS WILL FINALLY WARM UP INTO THE
60S FRIDAY THROUGH SUNDAY WITH LOWS ALSO MODERATING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY)
ISSUED AT 345 PM CDT SUN MAY 11 2014
CONVECTION IS EXPECTED TO FORM IN NORTHWEST IA AND ADJACENT AREAS
THIS EVENING...AND WAS INCLUDED IN THE KFSD AND KSUX TAF SITES. IT
IS POSSIBLE THAT SOME OF THE STORMS COULD BECOME RATHER STRONG
ESPECIALLY CLOSE TO AN INVERTED TROUGH NEAR SIOUX CITY AND STORM
LAKE...EXTENDING NORTHEASTWARD TO AROUND SPENCER IA. FURTHER
WEST... CONDITIONS WILL BE MORE STABLE AT KHON SO ONLY RAIN WAS
MENTIONED THERE. THE CATEGORIES WILL LIKELY LOWER INTO THE IFR AND
LOWER END MVFR CATEGORIES BY OVERNIGHT AND LASTING THROUGH MONDAY
MORNING.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
SHORT TERM...CHENARD
LONG TERM...MJ
AVIATION...
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
1212 PM CDT SUN MAY 11 2014
.UPDATE...
ISSUED AT 1144 AM CDT SUN MAY 11 2014
COMPLEX FORECAST THIS AFTERNOON INTO THE OVERNIGHT. CURRENT ANALYSIS
SHOWS SURFACE LOW PRESSURE OVER WESTERN KANSAS. KIND OF A DUAL WARM
FRONT SIGNATURE. WITH MAIN AND STRONGEST WARM FRONT ACROSS FAR
SOUTHERN NEBRASKA INTO SOUTHWEST IOWA...WHICH WAS REINFORCED BY THE
OVERNIGHT MCS. MODELS IN GOOD AGREEMENT WITH THE POSITION OF THIS
FRONT...AND ALL GUIDANCE SUGGESTS IT DOES NOT MOVE MUCH TODAY. THIS
IS THE AREA AT GREATEST RISK FOR SEVERE WEATHER AND TORNADOES...AS
HIGHLIGHTED BY THE SPC OUTLOOK. FURTHER NORTH EXPECT A SECONDARY WARM
FRONT TO SETUP. NAM IS FURTHEST NORTH WITH THIS FEATURE...PUSHING IT
AS FAR NORTH AS SIOUX CITY TO SPENCER. RAP AND HRRR KEEP IT MAINLY
JUST SOUTH OF THE CWA. IT IS POSSIBLE THAT MARGINAL SURFACE BASED
INSTABILITY COULD DEVELOP NEAR AND SOUTH OF THIS SECOND BOUNDARY.
ALTHOUGH MID LEVEL CLOUDINESS MAY MAKE THIS TOUGH...SO WILL NEED TO
MONITOR TRENDS.
AS FAR AS PRECIPITATION CHANCES GO...THINK WE SEE OFF AN ON SHOWERS
THROUGH THE DAY BUT NOTHING TOO SIGNIFICANT. WE WILL HAVE TO WAIT FOR
DEVELOPMENT LATER THIS AFTERNOON INTO TONIGHT AS LARGE SCALE FORCING
AND THETAE ADVECTION BOTH INCREASE. UNCERTAINTY ON WHERE IT RAINS
IS HIGH...AND LIKELY DEPENDENT ON HOW THE CONVECTION ACROSS NEBRASKA AND
IOWA IMPACT INFLOW INTO OUR REGION. THE STRONGEST SURFACE BASED
SUPERCELLS WILL LIKELY RIDE NEAR THE SOUTHERN WARM FRONT AND STAY
SOUTH OF OUR CWA. HOWEVER DO THINK WE WILL SEE STORMS FIRE CLOSER TO
THE SECONDARY WARM FRONT AS WELL...AND THESE WOULD IMPACT NORTHWEST
IOWA INTO SOUTHWEST MINNESOTA. AS MENTIONED ABOVE...IF WE WERE TO GET
SOME SURFACE BASED INSTABILITY FROM SIOUX CITY TO STORM LAKE...THERE
WOULD BE A TORNADO THREAT GIVEN THE VERY STRONG LOW LEVEL AND DEEP
LAYER SHEAR. AT THIS POINT CONTINUE TO THINK THIS IS A LOW
PROBABILITY EVENT...AND WILL KEEP OUT OF THE HWO FOR NOW...BUT
SOMETHING TO KEEP AN EYE ON. MORE LIKELY THAT STORMS ARE
ELEVATED...ALTHOUGH TURNING OF THE WINDS IS STILL STRONG ALOFT. THUS
ELEVATED SUPERCELLS WITH LARGE HAIL STILL SEEM POSSIBLE. ELEVATED
INSTABILITY IS PRESENT ALL THE WAY TO ALMOST THE JAMES RIVER.
QUESTION IS HOW MUCH MOISTURE WE CAN GET ADVECTED INTO THE CWA...WITH
THE CONVECTION TO OUR SOUTH HAMPERING THIS TO A DEGREE. IF STORMS
WERE TO FORM TOWARDS INTERSTATE 29...LARGE HAIL WOULD BE
POSSIBLE...GIVEN THE STEEP LAPSE RATES AND STRONG ELEVATED WIND
SHEAR. SO THE HIGHEST SEVERE THREAT...FOR MAINLY LARGE HAIL...REMAINS
IN NORTHWEST IOWA...ALTHOUGH A CONDITIONAL THREAT EXISTS ACROSS
SOUTHEAST SOUTH DAKOTA AND SOUTHWEST MINNESOTA...AND WILL ADD MENTION
INTO THE HWO.
&&
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 414 AM CDT SUN MAY 11 2014
CONVERGENCE ALONG 925 MB BOUNDARY STARTING TO LIGHT UP WITH STORMS.
AS THIS BOUNDARY LIFTS NORTH THROUGH THE MORNING...EXPECT FIRST WAVE
OF STORMS TO MOVE INTO NORTHWEST IOWA. WITH LIMITED AMOUNTS OF
INSTABILITY...AM NOT EXPECTING SEVERE WEATHER BUT COULD GET SOME
SMALL HAIL. FURTHER BACK TO THE WEST...DEFORMATION BAND OF SHOWERS
SHOULD CONTINUE TO PROGRESS TO THE NORTH THROUGHOUT THE MORNING
HOURS. THEREAFTER...EXPECT BREAK IN CONVECTION BUT CLOUD COVER WILL
BE A CONCERN THIS FAR TO THE NORTH IN TERMS OF DESTABILIZATION.
MODELS STILL SUGGEST THAT SURFACE BOUNDARY WILL TRY TO WORK NORTH
LATE THIS AFTERNOON INTO FAR SOUTHEAST CORNER OF THE FORECAST AREA
NEAR STORM LAKE TO SPENCER. IF BOUNDARY IS ABLE TO WORK THAT FAR
NORTH...POTENTIAL FOR SURFACE BASED CONVECTION INCLUDING
TORNADOES... STRONG VEERING PROFILES CERTAINLY SUPPORTIVE OF
SUPERCELLS...WITH HELICITY VALUES EXCEEDING 600 M2/S2. WITH SUCH
STRONG SPIN IN THE ATMOSPHERE...ADDED MENTION OF LARGE HAIL IN THE
GRIDS-BUT HELD OFF ON MENTION OF DAMAGING WINDS AND TORNADOES AS
QUESTION OF WHETHER SURFACE BASED CONVECTION WILL BE ABLE TO SURVIVE
THIS FAR NORTH. FOR TONIGHT...PWAT VALUES CONTINUE TO CLIMB THROUGH
THE EVENING HOURS TO NEARLY 1.5 INCHES EAST OF THE 925 HPA
BOUNDARY. IN ADDITION TO MENTION OF LARGE HAIL IN THE SOUTH
EAST...HAVE ALSO ADDED A MENTION OF HEAVY RAIN POTENTIAL.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 414 AM CDT SUN MAY 11 2014
STRONG 700 MB FRONTOGENETIC BAND PERSISTS ACROSS THE FORECAST AREA
THROUGH THE DAY ON MONDAY...STRETCHING NEARLY NORTH TO SOUTH THROUGH
THE CENTER OF THE FORECAST AREA. THERE ARE SOME SLIGHT MODEL
DIFFERENCES IN THE LOCATION OF THIS BAND...WITH THE NAM...GFS AND
GEM FURTHER WEST OF CENTER THAN THE ECMWF. WIDESPREAD RAIN
SHOWERS...PERHAPS MORE STRATIFORM IN NATURE WILL BE ONGOING ACROSS
MUCH OF SOUTHEAST SOUTH DAKOTA. TO THE EAST...REMNANTS OF NOCTURNAL
CONVECTION WILL LIKELY ALSO BE ONGOING IN NORTHWEST IOWA AROUND
DAYBREAK...MAINLY ACROSS OUR FAR SOUTHWEST CORNER. EXPECT THIS
ACTIVITY TO WANE BY LATE MORNING...WITH ADDITIONAL RAIN SHOWERS AND
SOME LINGERING THUNDER IN THE FAR EAST ARRIVING IN THE AFTERNOON AS
THE MID LEVEL FRONT SHIFTS EASTWARD. WITH THE ELONGATED TROUGH
SWINGING THROUGH THE FORECAST AREA...BREEZY NORTHWESTERLY
WINDS...AND CLOUDS AND RAIN WILL MAKE FOR AN UNSEASONABLY BRISK DAY.
TEMPERATURES LIKELY WILL NOT FLUCTUATE MUCH FROM MORNING LOWS WITH
HIGHS ONLY REACHING THE UPPER 40S TO LOWER 50S IN SE SD...AND THE
MID 50S TO NEAR 60 IN OUR EASTERN HALF OF THE CWA.
HEADING INTO MONDAY NIGHT...THE NAM BECOMES A SIGNIFICANT OUTLIER IN
DEVELOPING A UPPER LEVEL CLOSED LOW OVER NORTH CENTRAL NEBRASKA
WHILE THE OTHER MODELS LIFT THE TROUGH INTO THE UPPER MIDWEST
OVERNIGHT. AS A RESULT...THE NAM IS MUCH SLOWER IN SHUTTING OFF THE
PRECIPITATION FOR THE REGION. GIVEN THE BETTER AGREEMENT WITH THE
OTHER MODELS...DISCOUNTED THE NAM SOLUTION. LIGHT RAIN TAPERS OFF
FROM SOUTH TO NORTH MONDAY NIGHT AND DRIER NORTHWEST FLOW RETURNS TO
THE NORTHERN PLAINS.
THE TROUGH DOES MANAGE TO BECOME HUNG UP OVER THE UPPER MIDWEST WITH
SEVERAL IMPULSES POTENTIALLY CLIPPING THE FORECAST AREA.
OVERALL...BELOW NORMAL TEMPERATURES APPEAR TO BE THE RULE WITHOUT
ANY REAL SIGN OF A WARMING TREND UNTIL THE VERY END OF THE WEEK.
COULD SEE SOME ISOLATED SHOWERS CLIP OUR NORTHEASTERN HALF ON
TUESDAY AFTERNOON. WITH SO MUCH MODEL UNCERTAINTY...DID NOT STRAY
TOO FAR FROM ALLBLEND GUIDANCE FOR POPS MID TO LATE WEEK. WITH
PRETTY DRY LOW LEVELS...SUBSTANTIAL PRECIPITATION MAY BE HARD TO
COME BY. BUT WILL LEAVE IN SOME SLIGHT CHANCE SHOWERS WEDNESDAY AND
THURSDAY AND AGAIN ON SATURDAY. HIGHS PRIMARILY IN THE 50S...WARMING
BACK INTO THE 60S BY SATURDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 634 AM CDT SUN MAY 11 2014
LEADING STRATIFORM MCS IS EXPECTED TO WEAKEN AS IT LIFTS
NORTHEAST...BUT SHOULD STILL PRODUCE A FEW HOURS OF SHOWERS AND
THUNDERSTORMS ACROSS NORTHWEST IOWA THIS MORNING. EXPECT MVFR
STRATUS TO DEVELOP THROUGHOUT THE DAY UNDER EASTERLY FLOW AHEAD OF
WARM FRONT LIFTING NORTH. AS COLD FRONT/INVERTED TROUGH SHIFTS
EAST...LOWER STRATUS SHOULD AFFECT THE AREA CONTINUING THROUGH THE
OVERNIGHT. PRECIPITATION TIMING ON BACKSIDE OF THIS SYSTEM
SOMEWHAT FUZZY RIGHT NOW...BUT LOW END MVFR TO IFR STRATUS
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
UPDATE...CHENARD
SHORT TERM...
LONG TERM...
AVIATION...
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
325 PM CDT SUN MAY 11 2014
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 325 PM CDT SUN MAY 11 2014
FOCUS OF THE FORECAST IS ON RAIN THROUGH TUESDAY.
REGIONAL RADARS SHOW A CONVECTIVE COMPLEX HAS SURVIVED FROM THE
OVERNIGHT HOURS AND CONTINUES TO TRANSLATE ACROSS SOUTHERN IOWA.
THAT HAS EFFECTIVELY PINNED THE WARM FRONT WELL SOUTH OF THE AREA
ALONG THE IOWA/MISSOURI BORDER. THIS HAS ALSO PINNED MOST OF THE
CAPE TO THE SOUTH WITH THE 19Z MU CAPE SHOWING LESS THAN 500 J/KG
ACROSS THE AREA. THE CONCERN BECOMES WHAT HAPPENS THIS EVENING AS
THE COMPLEX CONTINUES TO MOVE EAST AND IF THE WARM FRONT CAN MAKE
A MOVE NORTH. THE 11.17Z HRRR SUGGESTS THAT THE WARM FRONT WILL
START TO PUSH NORTH THIS EVENING BUT MAY STILL BE ONLY ABOUT AS
FAR NORTH AS THE INTERSTATE 80 CORRIDOR BY 03Z. THE WARM FRONT
COULD THEN GET PUSHED NORTHEAST THROUGH THE REST OF THE EVENING
AND NIGHT AS A STRONG SHORT WAVE TROUGH MOVES NORTHEAST ACROSS THE
REGION. THE 11.12Z NAM DOES SUGGEST BETWEEN 1000-1500 J/KG OF ML
CAPE WILL BE IN PLACE ALONG AND NEAR THE WARM FRONT...BUT IF THE
WARM FRONT GETS PUSHED NORTHEAST...THIS CAPE MAY JUST CLIP THE
SOUTHEAST PORTIONS OF THE AREA. HOWEVER...IF THIS SCENARIO DOES
NOT PLAY OUT AND THE CAPE IS FARTHER WEST...THERE WILL STILL BE A
SEVERE THREAT. THE 0-6KM SHEAR THIS EVENING SHOULD INCREASE TO A
RANGE OF 30 TO 50 KNOTS THIS EVENING THEN TO AROUND 60 KNOTS FOR
THE OVERNIGHT HOURS. THE NAM REMAINS CONSISTENT SHOWING 200-300
M2/S2 OF HELICITY OVER THE AREA IN THE 0-3KM LAYER WITH THE BULK
OF THE RESIDING THE 0-1KM LAYER. SO IF THE WARM FRONT CAN GET INTO
THE AREA...THERE WOULD STILL BE A THREAT FOR AN ISOLATED
TORNADO...BUT CONFIDENCE ON THE POSITION OF THE WARM FRONT IS NOT
VERY HIGH.
CONFIDENCE IS HIGH THAT IT WILL RAIN TONIGHT. THE MODELS HAVE BEEN
CONVERGING TOWARD THE SCENARIO THAT AS THE SHORT WAVE TROUGH
COMES OUT OF THE CENTRAL PLAINS AND MOVES NORTHEAST OVER THE
REGION TONIGHT THAT CONVECTION WILL FORM ALONG AN INVERTED TROUGH.
THIS TROUGH CURRENTLY EXTENDS FROM THE SOUTHWEST KANSAS ACROSS
WESTERN IOWA INTO WESTERN WISCONSIN. AS THE SHORT WAVE TROUGH
COMES OUT...MODERATE PV ADVECTION IN THE 500-300 MB LAYER IS
EXPECTED TO OCCUR. IN THE LOW LEVELS...THE WARM AIR ADVECTION WILL
INCREASE AHEAD OF THE WAVE WITH 5 TO 7 UBAR/S OF UP GLIDE ON THE
300K ISENTROPIC SURFACE WITH THE MOISTURE TRANSPORT ON THIS LEVEL
RIGHT INTO THE AREA. EXPECT TO SEE THE LINE OF CONVECTION DEVELOP
IN RESPONSE TO THIS WAVE FROM SOUTHERN MINNESOTA INTO KANSAS AND
THEN MOVE NORTHEAST ACROSS THE AREA THROUGH THE NIGHT. ONCE THE
SHORT WAVE TROUGH MOVES PAST...THE FORCING WILL SHIFT BACK TO THE
WEST AGAIN AHEAD OF THE MAIN LONG WAVE TROUGH AND THE EMBEDDED
SHORT WAVE TROUGH. THIS IS EXPECTED TO MAKE THE MAIN SURFACE LOW
MOVE FROM KANSAS INTO MINNESOTA OR WISCONSIN DURING THE DAY
MONDAY WITH THE COLD FRONT ADVANCING EAST INTO THE AREA. ANOTHER
ROUND OF VERY SIMILAR ISENTROPIC UP GLIDE AND MOISTURE TRANSPORT
IS EXPECTED ON THE 300K SURFACE FOR CONTINUED SHOWERS AND
THUNDERSTORMS AHEAD OF THE FRONT. EVERYTHING THEN STARTS TO
TRANSLATE EAST FOR MONDAY NIGHT WITH THE RAIN CHANCES ENDING FROM
WEST TO EAST THROUGH TUESDAY MORNING.
.LONG TERM...(WEDNESDAY THROUGH SUNDAY)
ISSUED AT 325 PM CDT SUN MAY 11 2014
WILL CARRY SOME SMALL RAIN CHANCES FOR WEDNESDAY THROUGH FRIDAY
AND THEN SOME ON AND OFF CHANCES OVER THE WEEKEND. ONCE THE SYSTEM
FROM EARLY IN THE WEEK MOVES PAST...THE LONG WAVE TROUGH LOOKS TO
REMAIN OVER THE CENTRAL PART OF THE COUNTRY WITH A NORTHWEST FLOW
FROM NORTHWEST CANADA. THIS SHOULD ALLOW SEVERAL WEAK SHORT WAVE
TROUGHS TO ROTATE THROUGH THE LONG WAVE TROUGH TO SUPPORT THE RAIN
CHANCES. THIS FLOW WILL ALSO HELP TO KEEP TEMPERATURES BELOW
NORMAL WITH HIGHS IN THE 50S TO END THE WEEK AND THEN CREEPING
BACK INTO THE 60S FOR THE WEEKEND. OVERNIGHT LOWS WILL BE IN THE
30S AND MAY HAVE TO DEAL WITH SOME FROST HEADLINES TOWARD THE END
OF THE WEEK.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1227 PM CDT SUN MAY 11 2014
MUCH OF THE NEXT 24 HRS WILL BE DOMINATED BY SHRA/TSRA IN AND AROUND
THE AREA. FIRST BAND OF MAINLY -SHRA WILL MOVE ACROSS THE TAF SITES
EARLY THIS AFTERNOON WITH LCL MVFR VSBYS IN THE -RA BUT CIGS MOSTLY
IN THE 5K-8KT FT RANGE. AREA LOOKS TO GET A BREAK FROM THE SHRA/TSRA
FOR THE MID AFTERNOON INTO EARLY EVENING HOURS AS THE MAIN FORCING
IS FOCUSED MORE INTO SOUTHERN/EASTERN IA. VFR CONDITIONS EXPECTED FOR
MUCH OF THE MID AFTERNOON TO EARLY EVENING HOURS. DEEPER MOISTURE
AND STRONGER FORCING/LIFT SPREAD BACK INTO THE AREA BY MID EVENING
WITH A BROAD AREA OF SHRA/TSRA EXPECTED TO OVERSPREAD THE TAF SITES
IN ROUGHLY THE 03Z-12Z TIME-FRAME. MAINLY VFR/MVFR CIGS/VSBYS
EXPECTED IN THE SHRA/TSRA WITH IFR CIGS/VSBYS IN +TSRA AND THE HEAVY
DOWNPOURS. THESE DO NOT LOOK TO PREVAIL AT THE TAF SITES...BUT 12 TO
18 HRS OUT THEY REMAIN DIFFICULT TO TIME THUS INCLUSION OF A LONGER
THAN DESIRED PERIOD TEMPO IFR CONDITIONS LATER TONIGHT. NOT A LOT OF
CONFIDENCE IN THE DETAILS FOR MON MORNING BUT APPEARS AREA WILL GET
A BREAK FROM THE HEAVIER/STRONGER/MORE WIDESPREAD TSRA. GIVEN THE
UNCERTAINTY...FOR NOW CARRIED 5SM -SHRA WITH CB THRU MON MORNING
&&
.HYDROLOGY...
ISSUED AT 325 PM CDT SUN MAY 11 2014
RAINFALL FROM THIS SYSTEM THROUGH MONDAY SHOULD AVERAGE AROUND 2
INCHES FOR MUCH OF THE FORECAST AREA WITH LOCALIZED HIGHER AMOUNTS
EXPECTED. MANY OF THE RIVERS REMAIN HIGH FROM RECENT RUN OFFS AND
THE LATEST FORECASTS FROM THE RFC INDICATED WITHIN BANK RISES FOR
MANY OF THE TRIBUTARIES WITH RENEWED FLOODING POSSIBLE AT SOME
SPOTS ALONG THE MISSISSIPPI. IF THE RAINFALL ENDS UP BEING HIGHER
THAN THE QPF USED BY THE RFC...WHICH IS HIGH PROBABILITY...SOME
THE TRIBUTARIES COULD ALSO GO TO FLOOD. BASED ON THIS...HAVE OPTED
TO ISSUE A FLOOD WATCH FOR THE ENTIRE AREA FOR TONIGHT AND MONDAY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...FLOOD WATCH FROM 7 PM CDT THIS EVENING THROUGH MONDAY EVENING
FOR WIZ017-029-032>034-041>044-053>055-061.
MN...FLOOD WATCH FROM 7 PM CDT THIS EVENING THROUGH MONDAY EVENING
FOR MNZ079-086>088-094>096.
IA...FLOOD WATCH FROM 7 PM CDT THIS EVENING THROUGH MONDAY EVENING
FOR IAZ008>011-018-019-029-030.&&
$$
SHORT TERM...04
LONG TERM...04
AVIATION.....RRS
HYDROLOGY...04
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
225 PM CDT SUN MAY 11 2014
.REST OF THIS AFTERNOON AND TONIGHT - CONFIDENCE...MEDIUM SPC MESO
PAGE CONTINUES TO SHOW DESTABILIZATION IN THE MID LEVELS WITH MUCAPE
INCREASING. ELEVATED HAIL PRODUCING STORMS WILL MOVE TAKING SHAPE
ACRS NE IA. LOW LEVELS ALSO DESTABLIZED. SSW WINDS HAVE BROUGHT 60
PLUS DEW POINT AIR INTO PARTS OF SC WI. HAIL AND HEAVY RAIN APPEAR
TO BE THE MAIN THREATS DUE TO FAVORABLE MID LEVEL LAPSE RATES AND
MOISTURE ADVECTION. 0-6KM SHEAR NOT THAT FAVORABLE. FOR LATER
TONIGHT...UPPER TROUGH AND PRIMARY SHORTWAVE ENERGY AT THE BASE OF
TROUGH WILL CONTINUE TO SHIFT EAST FROM THE ROCKIES. A LEAD
SHORTWAVE PICKED UP BY THE MODELS IS EXPECTED TO REACH NW WI BY 12Z.
SURFACE LOW WILL HEAD NORTHEAST AND BECOME SOMEWHAT ELONGATED FROM
MN THROUGH WRN IA. WIND FLOW WILL RESPOND AND INCREASE FROM THE
SOUTH. LOW LEVEL JET DOES TRANSLATE EASTWARD A BUT THOUGH PRIMARY
FORCING IS WEST. HOWEVER ENOUGH MOISTURE ADVECTION AND SPEED
CONVERGENCE TO SUPPORT TSRA ACRS THE CWA. HRRR SHOWING POTENTIAL MCS
ARRIVING AFTER 7Z OR SO INTO WRN CWA. 12Z NAM AND 12Z GFS DO FOCUS
THE STRONGEST CONVECTION CLOSER TO THE NOSE OF THE JET TO OUR
WEST...HOWEVER 12Z ECMWF/12Z GEM LEAN THE JET CLOSER TO SRN WI WITH
QPF PANELS RESPONDING WITH A MORE ORGANIZED CONVECTIVE COMPLEX
TAKING SHAPE. GIVEN THE SHORTWAVE RIDING NORTHEAST AND PLACEMENT OF
LLJ AXIS...WILL PLAY IT THAT MORE ORGANIZED CONVECTION RETURNS LATER
TONIGHT AFTER A BREAK BETWEEN THE AFTN/EARLY EVE STORMS.
.MONDAY - CONFIDENCE...MEDIUM LEADING EDGE OF UPPER TROUGH DYNAMICS
PUSH INTO WRN IA AND WRN MN. STRONG SOUTHWEST UPPER FLOW ACRS SRN
WI. WARM SECTOR WILL BE WELL ENTRENCHED ACRS SRN WI. MODELS IN
GENERAL GREEMENT IN TAKING SURFACE LOW FROM MN TOWARDS NW WI.
WARM...MOIST AND UNSTABLE AIRMASS IN PLACE. THE UPPER JET WILL BE
WELL TO OUR WEST THOUGH MODELS HINTING AT SOME UPPER DIVERGENCE
HERE. BUFKIT SOUNDINGS SHOW DECENT MOISTURE WITH CAPES OVER 1000
J/KG. SO REAL EMPHASIS WILL BE ON THE TRIGGER. 4KM SPC WRF SHOWS
GENERAL WARM SECTOR/AIRMASS DEVELOPMENT WITH MAIN FOCUS FURTHER WEST
IN CLOSER PROXIMITY TO THE COLD FRONT. 925 TEMPS WILL BE AROUND
20C... SOME LAKE COOLING POSSIBLE BUT NOT EXPECTING MUCH OF AN
INLAND PUSH WITH THAT...SO EXPECT HIGHS WELL INTO THE 70S WITH A FEW
LOW 80S.
.MONDAY NIGHT...FORECAST CONFIDENCE - MEDIUM.
RIGHT ENTRANCE REGION OF UPPER JET PASSES ACROSS SRN WI AS SFC CDFNT
MOVES ACROSS. PWAT VALUES WILL REMAIN IN THE 1.5 INCH RANGE AHEAD
OF THE FRONT WITH DEEP WARM CLOUD DEPTH AND MBE VELOCITY LESS THAN
10 KNOTS MOST OF THE NIGHT. 925-850MB MOISTURE FLUX CONVERGENCE
INCREASES ONCE AGAIN BUT DOES NOT REMAIN ORIENTATED WITH THE MEAN
STEERING FLOW. NEVER THE LESS...POTENTIAL FOR HEAVY RAINFALL WL
CONTINUE DURING THIS PD DUE TO STRONG FORCING AND DEEP MOISTURE.
.TUESDAY THROUGH WEDNESDAY...FORECAST CONFIDENCE - HIGH.
SFC CDFNT WILL BE EXITING SOUTHEAST WISCONSIN EARLY TUESDAY MORNING.
LINGERING SHRA IN ITS WAKE SHOULD GRADUALLY DIMINISH FROM WEST TO
EAST AS COOLER...DRIER AIR SLOWLY WORKS ITS WAY ACROSS SRN WI AND
LOW LEVEL FRONTOGENETICAL FORCING SLIDES OFF TO THE EAST.
A QUIET AND COOL NIGHT IS EXPECTED TUESDAY NIGHT AS ANY INSTABILITY
-SHRA THAT WILL HAVE FORMED UPSTREAM IN THE AREA OF STEEP LOW TO MID
LEVEL LAPSE RATES SHOULD END WITH INSOLATION LOSS.
ON WEDNESDAY...MOST OF THE SHORT TERM GUIDANCE HINTING AT NEW SHORT
WAVE ROUNDING BASE OF LONG WAVE TROUGH OVER CENTRAL CONUS AND TAKING
NORTHEAST TRACK ALONG BAROCLINIC ZONE THROUGH TN AND OH VALLEY
REGION WED AND WED NGT. WL CONTINUE LOWER POPS FOR NOW WITH HIGHEST
IN THE SOUTHEAST WHERE PORTIONS OF SOUTHERN WI MAY BE ON THE
NORTHWEST SIDE OF THE EXPANDING PRECIP SHIELD WITH THIS SYSTEM.
.WEDNESDAY NIGHT THROUGH SUNDAY...FORECAST CONFIDENCE - MEDIUM.
BROADSCALE AGREEMENT IN THE MEDIUM RANGE GUIDANCE ON COOLER AIR
SETTLING INTO THE REGION AND LINGERING THROUGH THE END OF THE WEEK.
THIS WILL BE DUE TO LINGERING LONG WAVE TROUGH OVER CENTRAL CONUS
WHICH WILL BE SPREADING SLOWLY EWD THROUGH THE END OF THE WEEK. EWD
PROGRESSION OF TROUGH WL BE SLOWED BY WESTERN ATLANTIC BLOCKING
RIDGE. MID-UPPER LEVEL RIDGE AXIS EXPCD TO PERSIST OVER WI THROUGH
FRI. SHORT WAVE TROUGH APPROACHING PACIFIC NW WILL FINALLY NUDGE
TROF TO THE EAST OF WI FOR THE WEEKEND.
HENCE THE COOLER THAN NORMAL TEMPERATURES THAT WILL HAVE SETTLED
OVER SRN WI BY WED ARE EXPECTED TO LINGER INTO THE WEEKEND BEFORE
GRADUALLY WARMING. 85H TEMPS WL HAVE COOLED TO AROUND 0C BY WED AND
WL REMAIN A FEW DEGREES WITH 0C INTO SAT. IN ADDITION...WEAKER
SHORT WAVES ROTATING AROUND PARENT LONG WAVE TROUGH MAY BRING SOME
-SHRA TO SRN WI FROM WED THROUGH FRI. LAST SEVERAL RUNS OF THE
ECMWF HAVE BEEN SHOWING MORE POTENT LOW PRESSURE MOVING NORTHWARD
THROUGH TN/OH VALLEYS WED NGT INTO THU...WITH THE POTENTIAL FOR
PORTIONS OF SRN WI ON THE NORTHWEST WIDE OF THE -RA SHIELD FROM THIS
SYSTEM. CANADIAN AND GFS SHOW WEAKER RIPPLE AND ECMWF ENSEMBLE
FLATTENS THIS STRONGER SYSTEM AS WELL. HENCE FOR NOW WL CONTINUE
LOWER POPS FOR -SHRA WED NIGHT INTO THU.
EXPECTING MORE CLOUDS AND WEAK BOUNDARY LAYER MIXING TO KEEP
OVERNIGHT TEMPERATURES IN THE MIDDLE 30S TO LOWER 40S THURSDAY NIGHT
AND AGAIN FRIDAY NIGHT. HOWEVER IF MORE CLEARING IS EXPECTED IN
THESE PERIODS IN LATER FORECAST PERIODS...WL NEED TO CONSIDER ADDING
FROST TO THE LATE NIGHT FORECASTS.
&&
.AVIATION/12Z TAFS/...HRRR AND 4KM SPC WRF SHOW SOME ELEVATED STORMS
INTO SRN WI THIS AFTN/EVE WHICH LOOKS RIGHT ON GIVEN TRENDS IN 88-D.
LOOKING AT A BREAK A BIT LATER THIS EVE BEFORE POTENTIAL MCS ARRIVES
AFTER MIDNIGHT. THREAT THIS EVE LOOKS TO BE HAIL WITH DECENT MID
LEVEL LAPSE RATES. MORE DEVELOPMENT LIKELY TONIGHT AS LLJ REFOCUSES
TO OUR WEST AND THE LOW TO OUR WEST STRENGTHENS. NAM/GFS KEYING ON
IA/SE MN/ CNTRL/NRN WI THOUGH 12Z ECMWF/GEM AND HRRR SUGGEST STORMS
FOCUSED MORE INTO SRN WI. POTENTIAL FOR MORE SHRA/TSRA ON MONDAY
WITH WARM/HUMID/UNSTABLE AIRMASS THOUGH COLD FRONT STILL BACK TO OUR
WEST AND NOT EXPECTED TO ARRIVE UNTIL MONDAY NIGHT.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
TONIGHT/MONDAY AND AVIATION/MARINE...PC
MONDAY NIGHT THROUGH SUNDAY...MBK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1227 PM CDT SUN MAY 11 2014
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 245 AM CDT SUN MAY 11 2014
AXIS OF THE WEST COAST LONG WAVE TROUGH WILL SLIDE OVER THE PLAIN
STATES ON MON...SLOWLY EASING ACROSS THE UPPER MISSISSIPPI RIVER
VALLEY ON WED. BITS OF UPPER LEVEL ENERGY WILL SPIN OUT OF THE
TROUGH...WITH THESE SHORTWAVES TAKING AIM ON THE REGION TODAY AND
MONDAY.
AT THE SFC...A WARM FRONT CURRENTLY WAS RUNNING FROM KS EASTWARD
THROUGH THE MID MISSISSIPPI RIVER VALLEY. THIS IS SLATED TO LIFT
NORTHWARD THROUGH THE DAY TODAY AS A SFC LOW TRACKS INTO IA BY 06Z
TONIGHT. STRONG LOW LEVEL MOISTURE TRANSPORT POINTS INTO AND ACROSS
THE WARM FRONT...DRIVEN BY A 40-50 KT 850 MB JET...AND NOSES INTO
NORTHEAST IA/SOUTHWEST WI BY 06Z. THIS RIBBON OF MOISTURE HOLDS
AHEAD OF A COLD FRONT THROUGH MONDAY...ALTHOUGH NOT NEARLY AS STRONG
AS WHAT IS EXPECTED FOR TONIGHT.
INSTABILITY CLIMBS THROUGH THE DAY...WITH 1000-2000 J/KG OF MUCAPE
STILL EXPECTED FOR MUCH OF THE LOCAL FORECAST AREA BY TONIGHT. IT
STAYS FAIRLY UNSTABLE THROUGH MONDAY...STILL AHEAD OF THE COLD FRONT
WITH THE WARM FRONT EXPECTED TO BE NORTH...SBCAPES AROUND 1500 J/KG.
A LOOK AT THE BUFKIT SOUNDINGS SHOWS THAT MUCH OF THAT CAPE IS OF
THE SKINNY VARIETY TONIGHT...MEANING THAT VIGOROUS UPDRAFTS/RAPID
DEVELOPMENT ARE NOT SUPPORTED BY THE INSTABILITY.
0-6 KM SHEAR RAMPS UP TO 40-50 KTS BY THIS EVENING...BUT A LOT OF
THAT IN THE 0-3 KM LAYER...AROUND 40 KTS OR SO. GOOD TURNING IN THE
LOWEST 1 KM PER BUFKIT HODOGRAPH...AND 0-1 KM SHEAR RANGES FROM 20-30
KTS DURING THE NIGHT.
SEVERE THREAT HAS CONTINUED TO INCREASE OVER THE PAST COUPLE
DAYS...AND 00Z MODELS ARE NO DIFFERENT. THE STRONG LOW LEVEL
JET/MOISTURE TRANSPORT WILL BE A SIGNIFICANT FACTOR...ALONG WITH THE
POSITIONING OF THE WARM FRONT. WHILE THE INSTABILITY IS NOT OVERLY
FAVORABLE...ADD IN THE VERY GOOD SHEAR AND STORM DEVELOPMENT IS
SUPPORTED. LARGE HAIL AND DAMAGING WINDS ARE THREATS...WINDS
ESPECIALLY IF THERE IS NO NEAR SFC STABLE LAYER. THE LOW LEVEL
CURVATURE/SHEAR ALSO BRINGS A TORNADO THREAT...ESPECIALLY AROUND THE
WARM FRONT WHICH WILL SERVE TO PROVIDE ADDITIONAL...LOCALIZED
VORTICITY. NAM12 SIG TOR PARAMETER AS HIGH AS 2-4 THIS EVENING FOR
NORTHEAST IA/SOUTHWEST WI.
ITS NOT CLEAR-CUT ON HOW HIGH THE RISK FOR SEVERE WILL BE...OR WHERE
IT WILL BE THE GREATEST. POSITIONING OF THE WARM FRONT WILL BE
SIGNIFICANT. GFS/NAM TRENDING TOWARD BRINGING THAT FRONT INTO
CENTRAL IA INTO NORTHERN ILL...ADVANCING NORTH DURING THE
EVENING...NEAR THE I-90 CORRIDOR/SOUTH AROUND 06Z. ITS NOT CERTAIN
IT WILL RUN THIS FAST NORTH AS CONVECTION ALONG AND NORTH OF THE
BOUNDARY SHOULD SERVE TO TEMPER ITS MOVEMENT.
IN ADDITION...THERE WILL BE A THREAT FOR SOME SHOWERS/STORMS THIS
AFTERNOON...WELL BEFORE THE EXPECTED CONVECTION OF TONIGHT. THE LOW
LEVEL JET IS EXPECTED TO SPARK A THUNDERSTORM COMPLEX OVER THE
SOUTHERN PLAINS...WHICH THE HRRR TAKES NORTHEAST TOWARD THE AREA.
HOW LONG THE CONVECTION WILL HOLD TOGETHER AS THE LOW LEVEL
JET/MOISTURE TRANSPORT TEMPORARILY WEAKENS AT MIDDAY IS IN QUESTION.
ITS MCV COULD SERVE AS FORCING MECHANISM LATER IN THE AFTERNOON. IF
THE PCPN DOESN/T REACH THE FORECAST AREA...DEBRIS CLOUDS PROBABLY
WILL...AND COULD TEMPER THE WARMING AND THUS INSTABILITY SOME NORTH
OF THE WARM FRONT.
ALL THIS SAID...SEE A SEVERE THREAT TONIGHT...ESPECIALLY ACROSS
NORTHEAST IA/SOUTHWEST WI. PROBABLY MORE MID/LATE EVENING. HAIL IS
THE TOP THREAT...BUT SIGNIFICANT 0-3 KM SHEAR COULD RESULT IN
DAMAGING WINDS IF THERE IS NOT A STRONG STABLE NEAR SFC LAYER.
BUFKIT SOUNDINGS SUGGEST THERE PROBABLY WON/T BE. AND...A TORNADO
THREAT CANNOT BE RULED OUT. LOW LEVEL CURVATURE AND 0-1 KM SHEAR
SUPPORTS IT...AND THE SIG TOR PARAMETER PEGS IT. ESPECIALLY
CONCERNED ABOUT ANY STORMS RIDING THE WARM FRONT. THERE ARE CAVEATS
TO THE RISK PER WHERE CONVECTION GOES...BOUNDARIES...ETC...BUT ITS A
SITUATION THAT NEEDS TO BE MONITORED VERY CLOSELY. EXPECTING WATCHES
AND WARNINGS TONIGHT.
ALL THAT SAID AND HAVEN/T EVEN TOUCHED ON THE HEAVY RAIN THREAT.
MORE ON THAT IN THE HYDROLOGY SECTION BELOW.
.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 245 AM CDT SUN MAY 11 2014
GFS/ECMWF PROMISE TO KEEP THE REGION UNDER THE INFLUENCE OF AN UPPER
LEVEL TROUGH FOR MUCH OF THE NEW WEEK. BITS OF ENERGY WILL MOVE
THROUGH THE TROUGH AND BRING A SHOWER THREAT FROM TIME TO
TIME...ALTHOUGH WHEN/WHERE THE RAIN CHANCES WILL BE ARE NOT
CERTAIN...WITH MODEL VARIANCES KEEPING CONFIDENCE LOW. WILL STAY
WITH CONSENSUS SOLUTION FOR CHANCES. TEMPERATURES ARE GOING TO TAKE A
TUMBLE DOWNWARD...WITH EC 850 MB TEMP ANOMALIES HOVERING AROUND -1.
HIGHS WILL STRUGGLE TO BREAK 60 DEGREES SOME DAYS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1227 PM CDT SUN MAY 11 2014
MUCH OF THE NEXT 24 HRS WILL BE DOMINATED BY SHRA/TSRA IN AND AROUND
THE AREA. FIRST BAND OF MAINLY -SHRA WILL MOVE ACROSS THE TAF SITES
EARLY THIS AFTERNOON WITH LCL MVFR VSBYS IN THE -RA BUT CIGS MOSTLY
IN THE 5K-8KT FT RANGE. AREA LOOKS TO GET A BREAK FROM THE SHRA/TSRA
FOR THE MID AFTERNOON INTO EARLY EVENING HOURS AS THE MAIN FORCING
IS FOCUSED MORE INTO SOUTHERN/EASTERN IA. VFR CONDITIONS EXPECTED FOR
MUCH OF THE MID AFTERNOON TO EARLY EVENING HOURS. DEEPER MOISTURE
AND STRONGER FORCING/LIFT SPREAD BACK INTO THE AREA BY MID EVENING
WITH A BROAD AREA OF SHRA/TSRA EXPECTED TO OVERSPREAD THE TAF SITES
IN ROUGHLY THE 03Z-12Z TIME-FRAME. MAINLY VFR/MVFR CIGS/VSBYS
EXPECTED IN THE SHRA/TSRA WITH IFR CIGS/VSBYS IN +TSRA AND THE HEAVY
DOWNPOURS. THESE DO NOT LOOK TO PREVAIL AT THE TAF SITES...BUT 12 TO
18 HRS OUT THEY REMAIN DIFFICULT TO TIME THUS INCLUSION OF A LONGER
THAN DESIRED PERIOD TEMPO IFR CONDITIONS LATER TONIGHT. NOT A LOT OF
CONFIDENCE IN THE DETAILS FOR MON MORNING BUT APPEARS AREA WILL GET
A BREAK FROM THE HEAVIER/STRONGER/MORE WIDESPREAD TSRA. GIVEN THE
UNCERTAINTY...FOR NOW CARRIED 5SM -SHRA WITH CB THRU MON MORNING
&&
.HYDROLOGY...
ISSUED AT 245 AM CDT SUN MAY 11 2014
SIGNIFICANT LOW LEVEL MOISTURE TRANSPORT KICKS IN TONIGHT...AND
WHILE WEAKENING ON MONDAY...WILL CONTINUE TO FUEL SHOWERS AND
THUNDERSTORMS THROUGH MON NIGHT. PW/S CLIMB TO AROUND 1.5 INCHES.
EXPECT SOME STORMS OVER THE NEXT COUPLE DAYS TO PRODUCE HEAVY RAIN.
MODELS DROP 1-2 INCHES LATE TONIGHT INTO TUE FOR MUCH OF THE
FORECAST AREA. LOCALLY HIGHER AMOUNTS POSSIBLE. THE HEAVIEST RAIN
WILL FALL TONIGHT. DON/T EXPECT A WIDESPREAD FLOOD THREAT AT THE
MOMENT...BUT THERE COULD BE SOME LOCALIZED IMPACTS.
MEANWHILE...MINOR FLOODING/HIGH WATER CONTINUES ALONG PORTIONS OF
THE MISSISSIPPI RIVER. THE ADDITIONAL RAINS COULD HAVE IMPACTS ON
BOTH TRIBUTARIES AND THE MISSISSIPPI RIVER...SLOWING THE RATES OF
FALL...AND/OR PRODUCE ADDITIONAL RISES OR RENEWED FLOODING.
CHECK THE LATEST HYDROLOGIC STATEMENTS FOR THE DETAILS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...RIECK
LONG TERM....RIECK
AVIATION.....RRS
HYDROLOGY....RIECK