Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 05/26/13
AREA FORECAST DISCUSSION
NWS PUEBLO CO
808 PM MDT SAT MAY 25 2013
.UPDATE...
ISSUED AT 806 PM MDT SAT MAY 25 2013
ADJUSTED GRIDS/ZONES TO REFLECT ENDING OF RED FLAG WARNING THIS
EVENING WHILE ALSO CONTINUING THE RED FLAG WARNING FROM 11 AM MDT
SUNDAY TO 9 PM MDT SUNDAY FOR FIRE WEATHER ZONES
221-222-225-227-233 AND 237. ALSO ADJUSTED GRIDS AS NEEDED.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 301 PM MDT SAT MAY 25 2013
...FIRE WEATHER CONCERNS CONTINUE ACROSS THE MTS...AND INCREASE
ACROSS THE SOUTHERN PLAINS ON SUNDAY..
DEEPENING SFC LOW IN VCNTY OF KLHX HAS SPREAD SOME GUSTY SOUTHWEST
WINDS ACROSS THE MOUNTAINS AND SOUTHERN PORTIONS OF THE SE PLAINS.
AS OF 20Z...SFC DRY LINE IS LOCATED ALONG A LINE FROM JUST EAST OF
KLAA...TO NEAR KSPD. TO THE WEST OF THIS LINE...DEW POINTS HAVE BEEN
DROPPING INTO THE SINGLE DIGITS...TEENS AND EVEN SOME NEGATIVE
READINGS ACROSS THE MOUNTAINS. TO THE EAST OF THE DRY LINE...DEW
POINTS ARE STILL IN THE UPPER 40S TO LOWER 50S. LATEST HRRR STILL
PUSHES THE DRY LINE INTO WESTERN KS BY 22Z...WITH DEW POINTS
DROPPING INTO THE 30S ALONG THE EASTERN BORDER. STILL CONCERNED
THAT SOME INITIAL CONVECTION MAY FIRE ALONG THE DRY LINE LATE THIS
AFTERNOON...SO WILL MAINTAIN SOME ISOLATED POPS OUT THAT WAY. MOST
OF IT WILL BE HIGH BASED...WITH GUSTY WINDS AND LIGHTNING THE MOST
LIKELY THREATS. COULDN`T RULE OUT SOME MARGINAL SEVERE HAIL AND
WIND GUSTS NEAR THE CO/KS BORDER IF CAPES CAN STAY UP HIGH ENOUGH.
SPC HAS UPDATED THE LATEST OUTLOOK TO INCLUDE EASTERN
KIOWA...PROWERS...AND BACA COUNTIES. INITIALLY 0-6 KM SHEAR VALUES
ARE AROUND 20-30 KTS WHICH IS MARGINAL FOR SEVERE...BUT THESE VALUES
DO INCREASE INTO THE EVENING...SO THIS AREA WILL NEED TO BE
MONITORED. EXPECT CONVECTION TO SHIFT QUICKLY EASTWARD INTO KS
THROUGH THE LATE AFTN/EARLY EVENING...THOUGH OUTFLOWS MAY AID
WESTWARD RETREAT OF THE DRY LINE.
OVERNIGHT...DRY LINE PROGRESSES BACK WESTWARD BEFORE MIXING BACK
EASTWARD DURING THE DAY ON SUNDAY AS AN UPPER JET IN SOUTHWEST FLOW
ALOFT MOVES ACROSS THE AREA. CURRENT FIRE WEATHER WATCH WILL BE
UPGRADED TO A RED FLAG WARNING WITH THE AFTERNOON PACKAGE AS ALL
AREAS LOOK TO MEET CRITICAL FIRE WEATHER CONDITIONS. SFC BOUNDARY
HANGS UP JUST NORTH OF THE AREA AND WITH DRY LINE EXPECTED TO PUSH
INTO WESTERN KS DURING THE AFTERNOON...WILL GO WITH NIL POPS FOR THE
ENTIRE CWA. LOOKS LIKE HIGHS TOMORROW SHOULD STAY AROUND 3-5 DEGREES
BELOW RECORDS (COS 90...2012 PUB 97...2012 ALS 84...1969)...THOUGH
STILL WAY ABOVE CLIMATOLOGICAL AVERAGES. -KT
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 301 PM MDT SAT MAY 25 2013
SUNDAY NIGHT-MONDAY NIGHT...MODERATE WARM AND DRY SOUTHWEST FLOW
ALOFT CONTINUES ACROSS THE REGION AS A BROAD UPPER TROUGH SLOWLY
DIGS ACROSS THE PAC NORTHWEST AND INTO THE GREAT BASIN. MODELS
CONTINUE TO INDICATE A WEAK EMBEDDED SHORT WAVE TRANSLATING ACROSS
THE ROCKIES SUNDAY NIGHT WITH ANOTHER MINOR WAVE MOVING ACROSS THE
STATE LATE MONDAY AFTERNOON. FIRST WAVE SENDS A WEAK BACKDOOR COLD
FRONT ACROSS EASTERN COLORADO EARLY MONDAY MORNING BEFORE FRONT
MIXES OUT THROUGH THE EARLY AFTERNOON. MODELS ALSO INDICATING
INCREASING MID AND HIGH LEVEL MOISTURE ASSOCIATED WITH SECOND WAVE
SPREADING ACROSS THE AREA THROUGH THE DAY ON MONDAY...WHICH LOOKS TO
LIMIT STRONGER WINDS ALOFT FROM MIXING DOWN THROUGH THE AFTERNOON.
AT ANY RATE...COULD SEE BRIEF RED FLAG CONDITIONS DEVELOPING ACROSS
THE EASTERN MTS LATE MONDAY AFTERNOON...BUT LOOKS TO BE TOO MARGINAL
TO ISSUE ANY HIGHLIGHTS AT THIS TIME. WITH THE PASSING WAVES...COULD
SEE SOME HIGH BASED CONVECTION MONDAY AFTERNOON AND EARLY EVENING
ACROSS MAINLY THE CENTRAL AND EASTERN MTS WITH HIGHS EXPECTED TO BE
ONLY SLIGHTLY COOLER THAN SUNDAY.
TUESDAY-THURSDAY NIGHT...FIRE DANGER EXPECTED TO INCREASE ACROSS
SOUTHERN COLORADO AS GREAT BASIN UPPER TROUGH SLOWLY LIFTS OUT
ACROSS THE NORTHERN ROCKIES THROUGH THE PERIOD. INCREASING SOUTH TO
SOUTHWEST FLOW ACROSS THE AREA TUESDAY DEVELOPS A LA JUNTA LOW
TUESDAY AFTERNOON SUPPORTING THE POTENTIAL FOR CRITICAL FIRE WEATHER
CONDITIONS ACROSS THE SOUTHERN MTS AND ADJACENT PLAINS AS WELL AS
ACROSS THE FAR SOUTHEAST PLAINS...WITH SOME MORE HIGH BASED STORMS
POSSIBLE ACROSS THE CENTRAL MTS AND SOUTHWEST MTS. MORE WIDESPREAD
CRITICAL FIRE WEATHER CONDITIONS LOOK TO BE POSSIBLE ACROSS SOUTHERN
COLORADO WEDNESDAY AND THURSDAY WITH BREEZY TO WINDY WEST TO
SOUTHWEST FLOW ALOFT. PASSING TROUGH KEEPS CHANCE AND SLIGHT CHANCES
OF THUNDERSTORMS ACROSS THE AREA TUESDAY NIGHT THROUGH WEDNESDAY
NIGHT...WITH BEST CHANCES ACROSS NORTHERN PORTIONS OF THE AREA.
MODELS KEEP BEST LOW LEVEL MOISTURE WELL INTO WESTERN KANSAS
THOUGH LATEST ECMWF IS A TAD FURTHER WEST WITH DRY LINE WEDNESDAY
AFTERNOON AND WILL NEED TO MONITOR FOR POSSIBLE STORMS ACROSS THE
FAR SE PLAINS. AS FOR TEMPS...SHOULD SEE HIGHS FALLING BACK TO
AROUND SEASONAL AVERAGES THROUGH THE PERIOD WITH COOLING ALOFT.
FRIDAY-SATURDAY...COOL AND DRY NORTHWEST FLOW PROGGED TO DEVELOP
BEHIND PASSING TROUGH...KEEPING SLIGHT POPS DIURNAL POPS IN PLACE
ACROSS THE HIGH TERRAIN ALONG WITH TEMPERATURES SLIGHTLY BELOW
AVERAGE INTO THE EARLY WEEKEND.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 301 PM MDT SAT MAY 25 2013
VFR CONDITIONS EXPECTED AT TAF SITES WITH BREEZY SOUTH TO SOUTHWEST
WINDS GUSTING TO 25-30 KTS DECREASING TOWARDS 02Z. SHOULD SEE LIGHT
DIURNALLY DRIVEN WINDS OVERNIGHT...WITH BREEZY SOUTHWEST WINDS
RETURNING FOR THE TAF SITES SUNDAY AFTERNOON. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM 11 AM TO 9 PM MDT SUNDAY FOR COZ221-222-
225-227-233-237.
&&
$$
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
933 PM EDT SAT MAY 25 2013
.SYNOPSIS...
LOW PRESSURE NEAR THE NEW ENGLAND COAST WILL LIFT GRADUALLY TO THE
NORTHEAST THROUGH SUNDAY. MEANWHILE, HIGH PRESSURE LOCATED NEAR
NORTHWEST ONTARIO WILL BUILD TO THE SOUTH AND EAST. A SECTION OF THE
HIGH IS FORECAST TO PASS OVER OUR REGION AROUND MONDAY NIGHT BEFORE
MOVING OFF THE COAST. A WARM FRONT APPROACHING FROM THE SOUTHWEST IS
EXPECTED TO ARRIVE TUESDAY NIGHT AND WEDNESDAY. HIGH PRESSURE IS
THEN ANTICIPATED TO BUILD INTO OUR REGION FROM THE SOUTH FOR
THURSDAY THROUGH SATURDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
LOW PRESSURE WILL REMAIN NEAR THE COAST OF NEW ENGLAND THROUGH
TONIGHT. THIS WILL CONTINUE TO CIRCULATE A CHILLY AIRMASS ACROSS OUR
CWA WITHIN A CYCLONIC FLOW. THE FLOW ABOVE THE SURFACE WILL
GRADUALLY LESSEN THROUGH THE NIGHT, HOWEVER THE TIGHTENED PRESSURE
GRADIENT WILL MAINTAIN AT LEAST SOME WIND DESPITE THE BOUNDARY
LAYER COOLING. THE DEPTH OF THE MIXING LAYER WILL SHRINK THROUGH
THE NIGHT HOWEVER, WHICH WILL LESSEN THE SURFACE WINDS/GUSTS. THIS
HAS HAPPENED FAIRLY QUICKLY ALREADY THIS EVENING.
THERE CONTINUES TO BE PLENTY OF MOISTURE WRAPPING AROUND THE SURFACE
SYSTEM AND ALSO THE CLOSED UPPER-LEVEL LOW. AT THE SAME TIME, DRIER
AIR IS GETTING DRAWN IN FROM THE WEST AND SOUTHWEST. THERE WILL
STILL BE JUST ENOUGH LIFT GRAZING OUR FAR NORTHERN ZONES FOR
AWHILE THIS EVENING TO GENERATE AT LEAST SOME SPRINKLES. SINCE
THIS LOOKS RATHER LIGHT AND SPOTTY, AND RADAR RETURNS ARE NOW WEAK
WE OPTED TO CARRY SPRINKLES UP NORTH FOR THE REMAINDER OF THE
EVENING. HOWEVER, A MORE ORGANIZED AREA OF SHOWERS IS ROTATING
SOUTHWARD ACROSS EASTERN NEW YORK STATE. THIS APPEARS TO BE WITH A
SHORT WAVE AND DEFORMATION TYPE FEATURE. THE LATEST HRRR SHOWS
THIS FAIRLY WELL WITH IT WEAKENING AS IT ROTATES SOUTHEAST AND
THEN EAST. THIS MAY GET SOME SHOWERS INTO OUR FAR NORTHERN ZONES,
THEREFORE ADDED SOME 20-30 POPS LATE THIS EVENING BEFORE LOWERING
OVERNIGHT.
BASED ON A CONTINUATION OF AT LAST SOME WIND OVERNIGHT, THE THREAT
FOR ANY FROST IS RATHER LOW ATTM. NO MAJOR CHANGES WERE MADE TO
THE LOW TEMPERATURES ATTM. THE SKY COVER WAS ADJUSTED WHICH
INCLUDED A TIGHTER GRADIENT, WITH NEARLY A CLEAR SKY ACROSS THE
SOUTHERN AREAS. THERE ARE SOME MID TO HIGH LEVEL CLOUDS WELL TO
OUR SOUTHWEST, HOWEVER WITH THE UPPER-LEVEL FLOW FROM THE
NORTHWEST THESE SHOULD GENERALLY DIVE TO OUR SOUTH. THE HOURLY
TEMPERATURE/DEW POINT GRIDS WERE ADJUSTED STARTING WITH THE LATEST
OBSERVATIONS, THEN SOME OF THE LAMP/LAV GUIDANCE WAS BLENDED IN.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
MODERATING TREND EXPECTED AS TEMPERATURES WILL RUN 5 TO 10
DEGREES WARMER THAN TODAY. NW FLOW WILL CONTINUE OVER THE REGION
BUT WINDS WILL NOT BE AS STRONG. NO PRECIPITATION EXPECTED AND
CLOUD COVER GENERATED BY DAYTIME HEATING WILL NOT BE AS WIDESPREAD
AS TODAY, SO MOST AREAS WILL SEE QUITE A BIT MORE SUNSHINE THAN
THEY DID TODAY. PREVIOUS FORECAST TRACKED VERY WELL, AND HIGH
TEMPERATURES WERE LEFT UNCHANGED.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
A MID LEVEL LOW IS FORECAST TO BE LOCATED OVER NEW BRUNSWICK,
CANADA ON SUNDAY EVENING WITH A RIDGE AXIS EXTENDING FROM TEXAS TO
WESTERN ONTARIO. THE LOW WILL LIFT TO THE NORTHEAST. THE RIDGE
WILL BUILD TO THE EAST AND IT IS EXPECTED TO INFLUENCE OUR REGION
FROM THE MIDDLE OF THE WORK WEEK INTO NEXT WEEKEND. AS A RESULT,
WE ARE ANTICIPATING A WARMING TREND ALONG WITH INCREASING
HUMIDITY.
HIGH PRESSURE WILL CONTINUE TO BUILD INTO OUR REGION FROM THE
NORTHWEST FOR SUNDAY NIGHT AND MONDAY. A MAINLY CLEAR SKY IS
ANTICIPATED FOR SUNDAY NIGHT AND THE WIND SHOULD FALL BELOW 5 MPH
AT MOST LOCATIONS. TEMPERATURES ARE FORECAST TO DROP INTO THE 40S
IN MUCH OF OUR REGION. MINIMUM READINGS MAY BE IN THE LOWER 50S IN
HIGHLY URBANIZED AREAS. SOME SPOTS IN THE POCONOS AND IN FAR
NORTHERN NEW JERSEY COULD DROP INTO THE MIDDLE AND UPPER 30S AND
THERE MAY BE SOME PATCHY FROST FROM LATE SUNDAY NIGHT INTO EARLY
MONDAY MORNING. A LIGHT NORTHWEST TO WEST FLOW ON MONDAY WILL
LIKELY CONTINUE TO BRING DRY AIR INTO OUR REGION. THE DRY AIR
SHOULD WARM EFFICIENTLY AND WE ARE EXPECTING A 30 PLUS DEGREE
DIURNAL TEMPERATURE RANGE AT MOST LOCATIONS. AFTERNOON READINGS
ARE FORECAST TO RISE WELL INTO THE 70S.
ANOTHER COOL DRY NIGHT IS EXPECTED FOR MONDAY NIGHT AS SURFACE
HIGH PRESSURE PASSES THROUGH OUR REGION. THE AIR MASS WILL LIKELY
HAVE MODIFIED A BIT BY THAT TIME AND MINIMUM TEMPERATURES SHOULD
BE ABOUT 5 TO 7 DEGREES WARMER THAN THOSE ON SUNDAY NIGHT.
AS THE HIGH PASSES OFF THE COAST ON TUESDAY, THE SURFACE FLOW
SHOULD SWITCH TO THE SOUTHEAST AND SOUTH AND AFTERNOON
TEMPERATURES ARE FORECAST TO GET NEAR 80 DEGREES IN MUCH OF OUR
REGION.
A WARM FRONT APPROACHING FROM THE SOUTHWEST MAY BRING A SLIGHT
CHANCE OF SHOWERS TO OUR REGION BEGINNING ON TUESDAY AFTERNOON
WITH A BETTER CHANCE OF SHOWERS FOR TUESDAY NIGHT INTO WEDNESDAY.
AS CONDITIONS DESTABILIZE ON WEDNESDAY AFTERNOON WITH INCREASING
LOW LEVEL MOISTURE AND DAYTIME HEATING WE MAY SEE A FEW
THUNDERSTORMS, AS WELL.
THE WARM FRONT IS ANTICIPATED TO LIFT TO OUR NORTH FOR THURSDAY
THROUGH SATURDAY. WARM AND HUMID CONDITIONS ARE EXPECTED THROUGH
THE PERIOD. DAYTIME HIGH TEMPERATURES ARE FORECAST TO APPROACH 90
EXCEPT RIGHT ALONG THE COAST AND IN THE ELEVATED TERRAIN.
OVERNIGHT MINIMUM READINGS SHOULD BE MOSTLY IN THE 60S DUE TO THE
INCREASED HUMIDITY.
&&
.AVIATION /02Z SUNDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
TONIGHT...VFR, WITH CEILINGS AROUND 7,000 FEET FROM NEAR KABE TO
KPNE TO KACY NORTHWARD GRADUALLY THINNING OUT. NORTHWEST WINDS
AROUND 10 KNOTS WITH SOME LOCAL GUSTS TO NEAR 20 KNOTS THIS
EVENING, THEN MOST TERMINALS LOSING THE GUSTS.
SUNDAY...VFR. NORTHWEST WINDS INCREASING TO 15 TO 20 KNOTS WITH GUSTS
TO AROUND 25 KNOTS BY MID MORNING.
OUTLOOK...
SUNDAY NIGHT THROUGH TUESDAY...VFR.
TUESDAY NIGHT AND WEDNESDAY...CONDITIONS POSSIBLY LOWERING TO
MVFR AS A WARM FRONT LIFTS THROUGH OUR REGION. THERE IS A CHANCE
OF SHOWERS AND AFTERNOON THUNDERSTORMS.
WEDNESDAY NIGHT AND THURSDAY...MAINLY VFR WITH POSSIBLE MVFR
CONDITIONS IN HAZE AND FOG DURING THE LATE NIGHT AND EARLY MORNING
HOURS.
&&
.MARINE...
THE GALE WARNING WAS CANCELLED FROM LITTLE EGG INLET, NEW JERSEY
ON SOUTHWARD INCLUDING DELAWARE BAY. A SMALL CRAFT ADVISORY WAS
ISSUED FOR THESE AREAS THROUGH THE DAY SUNDAY. THE WINDS HAVE
DROPPED OFF QUITE A BIT THIS EVENING SO FAR, AND NOW IT IS A
MATTER OF HOW MUCH MIXING OCCURS. WE BELIEVE THE MIXING WILL NOT
BE ENOUGH TO ALLOW GALE FORCE GUSTS TO OCCUR, AND MODEL GUIDANCE
HOLDS 35-40 KNOTS OF WIND AT 925 MB FARTHER NORTH. THEREFORE WE
HELD ONTO THE GALE WARNING ACROSS THE NORTHERN TWO OCEAN ZONES
THROUGH 06Z TONIGHT FOR NOW. ONCE THIS GETS DROPPED, A SMALL CRAFT
ADVISORY WILL NEED TO BE RAISED. ON SUNDAY, THE MAIN GUSTS TO
AROUND 25 KNOTS MAY BE MORE NEARSHORE AS THE BOUNDARY LAYER WARMS
MORE COMPARED TO TODAY /SATURDAY/.
OUTLOOK...
HIGH PRESSURE WILL INFLUENCE THE COASTAL WATERS OF NEW JERSEY AND
DELAWARE FOR SUNDAY NIGHT THROUGH TUESDAY. A WARM FRONT IS
EXPECTED TO LIFT THROUGH OUR REGION DURING TUESDAY NIGHT AND
WEDNESDAY FOLLOWED BY ANOTHER AREA OF HIGH PRESSURE FOR THURSDAY.
WIND SPEEDS AND WAVE HEIGHTS WILL LIKELY REMAIN BELOW THE SMALL
CRAFT ADVISORY CRITERIA THROUGH THE PERIOD.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT SUNDAY FOR ANZ430-431-
452>455.
GALE WARNING UNTIL 2 AM EDT SUNDAY FOR ANZ450-451.
&&
$$
SYNOPSIS...GORSE/IOVINO
NEAR TERM...GORSE
SHORT TERM...SZATKOWSKI
LONG TERM...IOVINO
AVIATION...GORSE/SZATKOWSKI/IOVINO
MARINE...GORSE/SZATKOWSKI/IOVINO
AREA FORECAST DISCUSSION
NWS MIAMI FL
725 PM EDT SAT MAY 25 2013
.AVIATION...
HIGH PRESSURE CENTERED OVER THE SE UNITED STATES WILL KEEP SOUTH
FLORIDA IN A MOSTLY DRY NE/E WIND FLOW THROUGH THE DAY ON SUNDAY.
ONLY ISSUE IS WINDS WHICH WILL GUST TO AROUND 20 KT DURING THE
DAY. VFR CONDITIONS EXPECTED WITH PARTLY TO MOSTLY CLEAR SKIES.
MOLLEDA
&&
.PREV DISCUSSION... /ISSUED 236 PM EDT SAT MAY 25 2013/
SHORT TERM (TONIGHT-MONDAY NIGHT)...
PLENTY OF DRY AIR ALONG WITH RISING UPPER HEIGHTS IN THE WAKE OF THE
FRONTAL BOUNDARY THAT PASSED THROUGH TODAY WILL LEAD TO MORE OF A
SUPPRESSED ENVIRONMENT THROUGH THE REMAINDER OF THE WEEKEND. MODEL
TIME HEIGHTS/SOUNDINGS AROUND THE LOCAL AREA REFLECT THIS AND
GENERALLY INDICATE MOST OF THE MOISTURE REMAINING CONFINED WITHIN
THE LOWER 4 KFT UNDERNEATH A STRONG SUBSIDENCE INVERSION.
PRECIPITABLE WATER VALUES ARE FORECAST TO STEADILY DROP TONIGHT AND
BOTTOM OUT JUST ABOVE HALF OF AN INCH SUNDAY BEFORE STEADILY
TRENDING BACK UP INTO THE UPCOMING WEEK. HOWEVER...MODERATE
NORTHEASTERLY WINDS AND PLENTY OF LOW-LEVEL MOISTURE MAY ALLOW FOR A
FEW SHALLOW BRIEF SHOWERS TO DEVELOP OVER THE ADJACENT ATLANTIC
WATERS AND SPREAD ASHORE THROUGH THE REMAINDER OF THE
WEEKEND...ESPECIALLY THROUGH THE OVERNIGHT AND EARLY MORNING HOURS.
THIS LINES UP WELL WITH THE LATEST WRF SOLUTIONS...WHICH INDICATE A
FEW LIGHT SHOWERS DEVELOPING AND SPREADING ASHORE OVER THE NORTHERN
AREAS LATER TONIGHT INTO SUNDAY. ON MONDAY...DEEP EASTERLY FLOW UP
TO AROUND 18 KFT ALONG WITH INCREASING MOISTURE MAY LEAD TO FEW
SHOWERS DEVELOPING INLAND AND TOWARD THE GULF COAST AREAS THROUGH
THE AFTERNOON/EVENING HOURS. HOWEVER...IN THE ABSENCE OF A GULF
COAST SEA BREEZE DUE TO THE MODERATE EASTERLY FLOW IN PLACE ALONG
WITH THE MID-LEVEL DRY AIR...MAINLY BRIEF SHOWERS WILL BE
ANTICIPATED. ALONG THE EAST COAST...TEMPERATURES WILL REMAIN
SLIGHTLY BELOW NORMAL EACH DAY. 85/AG
LONG TERM (TUESDAY-FRIDAY)...
ADDITIONAL MOISTURE IS FORECAST TO ENTER THE REGION EARLY NEXT WEEK
AS A MID TO UPPER LEVEL TROUGH IS FORECAST TO DEEPEN IN THE EASTERN
GULF WITH A CHANCE OF SHOWERS AND THUNDERSTORMS RETURNING TO THE
REGION. THERE IS SOME CONSENSUS AMONGST THE MODEL GUIDANCE THAT
DEEPER LAYERED TROPICAL MOISTURE AND A DEEPENING OF THE MID TO UPPER
LEVEL TROUGH COULD OCCUR AROUND MID-WEEK AND PERSIST FOR A COUPLE OF
DAYS WITH MORE WIDESPREAD CONVECTION POSSIBLE. WILL HAVE TO WAIT AND
SEE IF FUTURE GUIDANCE PERSISTS WITH THESE SYNOPTIC FEATURES.
BD
AVIATION...
EASTERLY FLOW WILL PREVAIL THROUGH THE REMAINDER OF THE AFTERNOON
ACROSS THE SOUTH FLORIDA AREA WITH VFR CONDITIONS. A FEW SHOWERS
HAVE DEVELOPED THIS AFTERNOON ACROSS EXTREME SOUTHERN MAINLAND
MONROE COUNTY. THE LATEST HRRR DEPICTS A FEW MORE SHOWERS DEVELOPING
ACROSS THIS AREA AND IN COLLIER COUNTY OVER THE NEXT FEW
HOURS...POSSIBLY AFFECTING KAPF. BELIEVE THE SHOWER COVERAGE WILL BE
SPARSE AND DID NOT CARRY ANY MENTION FOR THE KAPF TAF. EASTERLY FLOW
SHOULD CONTINUE OVERNIGHT AT AROUND 10 KNOTS AT ALL TAF SITES BEFORE
BECOMING GUSTY AGAIN TOMORROW.
MARINE...
WINDS AND SEAS WILL QUICKLY INCREASE THROUGH THE REMAINDER OF THE
WEEKEND IN THE WAKE OF A WEAK FRONTAL BOUNDARY AS HIGH
PRESSURE BUILDS OVER THE REGION. ALTHOUGH ADVISORY LEVEL WINDS AND
SEAS ARE NOT ANTICIPATED AT THIS TIME...MARINERS OPERATING SMALL
CRAFT ARE ENCOURAGED TO EXERCISE CAUTION...MAINLY OVER THE ATLANTIC
WATERS THIS WEEKEND.
AT THE EAST COAST BEACHES...STRONG RIP CURRENTS WILL BE LIKELY BY
SUNDAY DUE TO MODERATE ONSHORE WINDS AND BUILDING SURF.
FIRE WEATHER...
DESPITE THE DRIER AIR THAT IS FORECAST TO SPREAD OVER THE AREA
THROUGH THE REMAINDER OF THE WEEKEND AND INTO THE UPCOMING
WEEK...RELATIVE HUMIDITIES ARE FORECAST TO REMAIN ABOVE CRITICAL
LEVELS EACH DAY. EASTERLY WINDS WILL BECOME GUSTY THROUGH THE
AFTERNOON PERIODS.
&&
.PRELIMINARY POINT TEMPS/POPS...
WEST PALM BEACH 72 82 73 83 / - 10 10 10
FORT LAUDERDALE 76 85 77 86 / - 10 20 10
MIAMI 75 84 75 85 / - 10 20 20
NAPLES 69 91 69 91 / - 10 10 20
&&
.MFL WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
GM...NONE.
&&
$$
PUBLIC/MARINE...71/JE
AVIATION/RADAR/FIRE...59/MOLLEDA
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
340 PM EDT FRI MAY 24 2013
.SYNOPSIS...
19Z WATER VAPOR AND H4 RAP ANALYSIS CONTINUE TO SHOW AN ACTIVE UPPER
LEVEL PATTERN IN PLACE OVER THE CONUS. LONGWAVE PATTERN IS DOMINATED
BY DEEP TROUGHS ALONG BOTH THE PACIFIC AND ATLANTIC COASTS WHILE A
LONGWAVE RIDGE AXIS BISECTS THE CONTINENT OVER THE CENTRAL PLAINS.
OUR FORECAST AREA RESIDES AT THE BASE OF THE EASTERN CONUS TROUGH.
A STRONG SHORTWAVE EMBEDDED WITHIN THIS TROUGH IS NOW DROPPING
SOUTHEASTWARD OVER THE MID-ATLANTIC/CAROLINAS. THIS ENERGY WILL NOT
ONLY ACT TO CLOSE OFF A POTENT UPPER LOW OFF THE NEW ENGLAND
COAST...BUT ITS MOMENTUM WILL ALSO HELP DRIVE A LATE SEASON COLD
FRONT DOWN AND THROUGH THE FLORIDA PENINSULA DURING THE NEXT 6-12
HOURS. 24/12Z KTBW SOUNDING PROFILE WAS DRY...BUT NOT UNSEASONABLY
DRY...JUST YET. HOWEVER LOOKING UPSTREAM TOWARD BIRMINGHAM AND
ATLANTA WE BEGIN TO SEE A MUCH DRIER AIRMASS ABOVE THE SURFACE WHICH
WILL BE SETTLING SOUTHWARD AND OVER OUR HEADS FOR THE HOLIDAY
WEEKEND.
AT THE SURFACE...AS MENTIONED ABOVE...A LATE SEASON COLD FRONT IS
READY TO ADVANCE THROUGH THE FORECAST AREA TONIGHT. THE FRONT IS
CURRENTLY ANALYZED JUST SOUTH OF THE I-10 CORRIDOR WITH A DISTINCT
DEWPOINT DISCONTINUITY FROM MUCH OF THE FLORIDA PENINSULA UP TO THE
FL PANHANDLE AND SOUTHERN PORTION OF AL/GA. THIS MORE COMFORTABLE
AIRMASS IS ON ITS WAY TO US FOR THE WEEKEND. SEEING JUST A FEW
ISOLATED SHOWERS DOWN TOWARD FT. MYERS LATE THIS AFTERNOON. A FEW
MORE ARE POSSIBLE TO THE SOUTH OF I-4 DURING THE NEXT FEW
HOURS...HOWEVER ANY SHOWERS WILL BE SMALL AND BRIEF IN NATURE WITH
VERY LOW OVERALL COVERAGE.
&&
.SHORT TERM (TONIGHT THROUGH SUNDAY NIGHT)...
TONIGHT...
SURFACE FRONT SLIPS SOUTH OF THE REGION FOLLOWED QUICKLY
BY STRONG CONTINENTAL HIGH PRESSURE RIDGING DOWN FROM THE NORTH. A
FAVORABLE NNE DRAINAGE FLOW WILL ALLOW SOME OF OUR NORTHERN AREAS
AROUND LEVY/CITRUS COUNTIES TO DROP INTO THE MID/UPPER 50S TOWARD
SUNRISE ON SATURDAY...WHILE THE REMAINDER OF THE REGION DROPS DOWN
INTO THE 60S. ANY ISOLATED EVENING SHOWERS OVER THE FAR SOUTHERN
ZONES WILL END WITH THE FRONTAL PASSAGE SETTING UP A DRY AND
PLEASANT OVERNIGHT PERIOD.
SATURDAY THROUGH SUNDAY NIGHT...
MID/UPPER LEVEL TROUGH AXIS WILL PUSH EAST OF THE SOUTHEAST CONUS
WITH BROAD SYNOPTIC SUPPRESSION IN ITS WAKE FOR THE WEEKEND. A VERY
DRY MID-LEVEL AIRMASS WITH THETA-E VALUES WELL BELOW 320K WILL BE
ARRIVING FROM THE NORTH PROVIDING A QUITE HOSTILE ENVIRONMENT FOR
DEEP CONVECTION. WITH THIS IN MIND...NEAR ZERO RAIN CHANCES ARE IN
THE FORECAST FOR BOTH SATURDAY AND SUNDAY OVER OUR ZONES. MAY STILL
BE JUST ENOUGH MOISTURE AND LOW LEVEL FORCING TO SUPPORT AN ISOLATED
SHOWER OVER FAR SOUTH FLORIDA...BUT SEEMS APPARENT THAT ANY ACTIVITY
WILL BE SOUTH OF OUR ZONES. LOW LEVEL FLOW WILL BE STRONG ENOUGH OUT
OF THE EAST THIS WEEKEND THAT WE ARE UNLIKELY TO EVEN SEE MUCH (IF
ANY) SEA-BREEZE DEVELOPMENT...ESPECIALLY ON SATURDAY.
LOW LEVEL TEMPERATURES WILL COOL OFF SOMEWHAT BEHIND THE
FRONT...HOWEVER DRY CONDITIONS AND EXCELLENT DIURNAL MIXING WILL
COMPENSATE...AND STILL KEEP US ENJOYING SEASONABLE TEMPERATURES.
UPPER 80S TO NEAR 90 WILL BE COMMON THE NEXT COUPLE OF DAY...EVEN
CLOSE TO THE BEACHES AS THE EASTERLY FLOW HOLDS THE SEA-BREEZE TO
THE COAST OR EVEN JUST OFFSHORE.
THE IMPACT OF THE FRONT WILL BE FELT MORE AT NIGHT WITH BELOW NORMAL
LOW TEMPERATURES. MAY LOCATIONS AWAY FROM THE IMMEDIATE COAST WILL
LIKELY DIP INTO THE MID/UPPER 50S AROUND SUNRISE SUNDAY MORNING.
ALONG THE COAST FROM TAMPA BAY SOUTHWARD LOWER TO MIDDLE 60S WILL BE
MORE COMMON. SUNDAY NIGHT LOW TEMPERATURES WILL BE UP A FEW DEGREES
FROM THOSE ON SATURDAY NIGHT...BUT REMAIN BELOW NORMAL FOR LATE MAY.
&&
.LONG TERM (MONDAY THROUGH NEXT FRIDAY)...
MODEL SOLUTIONS REMAIN IN GOOD AGREEMENT SHOWING HIGH PRESSURE RIDGE
AXIS REMAINING NORTH OF THE FORECAST AREA THROUGH THE LONG TERM
PERIODS...KEEPING AN EASTERLY BOUNDARY LAYER FLOW IN PLACE. MOISTURE
WILL REMAIN LIMITED THROUGH MONDAY NIGHT...WITH RAIN FREE CONDITIONS
EXPECTED. BOUNDARY LAYER MOISTURE WILL THEN SLOWLY INCREASE THROUGH
THE REMAINDER OF THE WEEK...SO WILL CARRY SLIGHT CHANCE/LOW CHANCE
POPS IN MOST AREAS TUESDAY THROUGH FRIDAY FOR AFTERNOON/EARLY
EVENING SHOWERS AND THUNDERSTORMS.
&&
.AVIATION...
VFR CONDITIONS WILL PREVAIL WITH FEW-SCT CLOUDS THROUGH THE
AFTERNOON. THERE MAY BE SOME ISOLD TSRA NEAR PGD/FMY/RSW BUT NOT
CLOSE ENOUGH TO CARRY IN THE TAF. NORTHWEST AND GUSTY WINDS DIMINISH
SOME OVER NIGHT AS THEY SHIFT TO NORTH THEN NE...BECOMING ROBUST
AFTER SUNRISE.
&&
.MARINE...
ROUGH BOATING CONDITIONS ARE EXPECTED AT TIMES OVER THE EASTERN GULF
OF MEXICO THIS HOLIDAY WEEKEND. A COLD FRONT WILL CROSS THE FORECAST
WATERS THROUGH TONIGHT ALLOWING STRONG HIGH PRESSURE TO RIDGE DOWN
FROM THE NORTH IN ITS WAKE. WINDS WILL SHIFT NORTHEAST OVERNIGHT AND
INCREASE TO CAUTIONARY LEVELS INTO SATURDAY MORNING. A BRIEF
REDUCTION IN THE WINDS IS POSSIBLE SATURDAY AFTERNOON...BUT EXPECT
EASTERLY FLOW WILL QUICKLY INCREASE ONCE AGAIN TO ADVISORY LEVELS
SATURDAY EVENING AND REMAIN ELEVATED THROUGH SUNDAY MORNING. THE
RIDGE POSITION WILL SUPPORT OVERNIGHT AND MORNING EASTERLY WIND
SURGES THROUGH THE EARLY PORTION OF NEXT WEEK.
&&
.FIRE WEATHER..
A DRY AIRMASS WILL ARRIVE ACROSS THE REGION FOR THE UPCOMING HOLIDAY
WEEKEND. THIS DRY AIRMASS WILL ALLOW RELATIVE HUMIDITY VALUES TO
DROP BELOW 35 PERCENT OVER MUCH OF THE AREA SATURDAY AFTERNOON. THE
LOW RELATIVE HUMIDITY IS ANTICIPATED TO COMBINE WITH GUSTY EAST TO
NORTHEAST WINDS AND ENERGY RELEASE COMPONENT VALUES OF 27 OR HIGHER
TO PRODUCE CRITICAL FIRE WEATHER CONDITIONS FOR LOCATIONS CURRENTLY
WITHIN THE FIRE WEATHER WATCH. DRY CONDITIONS ARE ALSO ANTICIPATED
FOR SUNDAY WITH THE BEST CHANCES OF CRITICAL RELATIVE HUMIDITY
VALUES BEING ALONG AND NORTH OF THE I-4 CORRIDOR. WINDS ARE NOT
EXPECTED TO BE AS STRONG DURING SUNDAY AND ANY POTENTIAL RED FLAG
CONDITIONS LOOK TO BE DEPENDENT ON HOW ERC VALUES FLUCTUATE DURING
THE WEEKEND.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 71 90 65 88 / 10 0 0 0
FMY 69 92 66 87 / 20 10 0 0
GIF 68 89 61 87 / 10 0 0 0
SRQ 70 90 65 88 / 10 0 0 0
BKV 64 88 56 88 / 10 0 0 0
SPG 74 89 68 87 / 10 0 0 0
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...FIRE WEATHER WATCH FROM SATURDAY AFTERNOON THROUGH
SATURDAY EVENING FOR CITRUS-DESOTO-HARDEE-HERNANDO-
HILLSBOROUGH-MANATEE-PASCO-PINELLAS-POLK-SARASOTA-
SUMTER.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/FIRE WEATHER...MROCZKA
MARINE...MROCZKA/MCMICHAEL
AVIATION/DECISION SUPPORT...RUDE
LONG TERM...JELSEMA
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
1120 AM EDT FRI MAY 24 2013
.UPDATE (REST OF TODAY AND TONIGHT)...
15Z WATER VAPOR AND H4 RAP ANALYSIS CONTINUE TO SHOW AN ACTIVE UPPER
LEVEL PATTERN IN PLACE OVER THE CONUS. LONGWAVE PATTERN IS DOMINATED
BY DEEP TROUGHS ALONG BOTH THE PACIFIC AND ATLANTIC COASTS WHILE A
LONGWAVE RIDGE AXIS BISECTS THE CONTINENT OVER THE CENTRAL PLAINS.
OUR FORECAST AREA RESIDES AT THE BASE OF THE EASTERN CONUS TROUGH. A
STRONG SHORTWAVE EMBEDDED WITHIN THIS TROUGH IS NOW DROPPING
SOUTHEASTWARD OVER THE MID-ATLANTIC/CAROLINAS. THIS ENERGY WILL NOT
ONLY ACT TO CLOSE OFF A POTENT UPPER LOW OFF THE NEW ENGLAND
COAST...BUT ITS MOMENTUM WILL ALSO HELP DRIVE A LATE SEASON COLD
FRONT DOWN AND THROUGH THE FLORIDA PENINSULA DURING THE NEXT 12-18
HOURS. 24/12Z KTBW SOUNDING PROFILE WAS DRY...BUT NOT UNSEASONABLY
DRY...JUST YET. HOWEVER LOOKING UPSTREAM TOWARD BIRMINGHAM AND
ATLANTA WE BEGIN TO SEE A MUCH DRIER AIRMASS ABOVE THE SURFACE WHICH
WILL BE SETTLING SOUTHWARD AND OVER OUR HEADS FOR THE HOLIDAY
WEEKEND.
AT THE SURFACE...AS MENTIONED ABOVE...A LATE SEASON COLD FRONT IS
READY TO ADVANCE THROUGH THE FORECAST AREA LATER TODAY AND TONIGHT.
THE FRONT IS CURRENTLY ANALYZED UP NEAR THE I-10 CORRIDOR WITH A
DISTINCT DEWPOINT DISCONTINUITY FROM MUCH OF THE FLORIDA PENINSULA
UP TO THE INTERIOR PANHANDLE AND SOUTHERN PORTION OF AL/GA. THIS
MORE COMFORTABLE AIRMASS IS ON ITS WAY TO US.
SOME EARLY MORNING PATCHES OF FOG ARE ALL BUT GONE LATE THIS MORNING
LEADING TO MOSTLY SUNNY SKIES REGION-WIDE. STILL HAVE ENOUGH
BOUNDARY LAYER MOISTURE AND EVENTUAL SEA-BREEZE FOCUS TO EXPECT A
SCT CUMULUS FIELD TO BECOME ESTABLISHED FOR THE AFTERNOON...MAINLY
ALONG AND SOUTH OF THE I-4 CORRIDOR. CAN NOT RULE OUT THE
POSSIBILITY FOR AN ISOLATED SHOWER OR 2 TO DEVELOP LATE
AFTERNOON/EARLY EVENING TO THE SOUTH OF I-4 WHERE FRONTAL AND
SEA-BREEZE CONVERGENCE ALIGN ENOUGH TO OVERCOME THE NO SO FAVORABLE
TROP FOR DEEP CONVECTION. ONLY HAVE POPS AROUND 20% FOR THESE
CENTRAL AND SOUTHERN ZONES...AND NO RAIN CHANCES NORTH OF I-4. ANY
ISOLATED SHOWERS THAT DO DEVELOP WILL LIKELY BE SHORT-LIVED AS THEY
QUICKLY ENTRAIN DRY AND HOSTILE THETA-E AIR ABOVE 700MB INTO THEIR
COLUMN.
TEMPERATURES THE REST OF THE DAY WILL BE SEASONABLE WITH MANY INLAND
LOCATIONS PEAKING WITHIN A DEGREE OR TWO OF 90. TYPICAL FOR THIS
TIME OF YEAR...DEVELOPING AND STRENGTHENING ONSHORE FLOW WILL KEEP
TEMPERATURES IN THE 80S NEAR THE BEACHES.
TONIGHT...SURFACE FRONT SLIPS SOUTH OF THE REGION FOLLOWED QUICKLY
BY STRONG CONTINENTAL HIGH PRESSURE RIDGING DOWN FROM THE NORTH. A
FAVORABLE NNE DRAINAGE FLOW WILL ALLOW SOME OF OUR NORTHERN AREAS
AROUND LEVY/CITRUS COUNTIES TO DROP INTO THE MID/UPPER 50S TOWARD
SUNRISE ON SATURDAY...WHILE THE REMAINDER OF THE REGION DROPS DOWN
INTO THE 60S. ANY ISOLATED EVENING SHOWERS OVER THE FAR SOUTHERN
ZONES WILL END WITH THE FRONTAL PASSAGE SETTING UP A DRY AND
SEASONABLE PLEASANT OVERNIGHT PERIOD. ENJOY!
&&
.AVIATION...
VFR CONDITIONS WILL PREVAIL WITH AT THE MOST FEW-SCT CLOUDS. NORTH
AND NORTHWEST WINDS...GUSTY AT TIMES THIS AFTERNOON.
&&
.MARINE...
WINDS WILL START TO INCREASE TO CAUTIONARY LEVELS FOR
OFFSHORE ZONES TONIGHT INTO EARLY SATURDAY MORNING WITH WAVE
HEIGHTS INCREASING TO UP TO 4 FEET. STRONG HIGH PRESSURE WILL
BUILD NORTH OF THE STATE OVER THE HOLIDAY WEEKEND AND INTO THE
MIDDLE OF NEXT WEEK. THIS WILL RESULT IN AN ELEVATED EASTERLY
FLOW ACROSS THE WATERS...WITH PERIODS OF EXERCISE CAUTION AND
ADVISORY HEADLINES NECESSARY FOR MOST MARINE ZONES...PARTICULARLY
DURING THE EVENING AND OVERNIGHT HOURS.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 89 69 90 66 / 10 10 0 0
FMY 91 70 91 65 / 20 20 0 0
GIF 93 67 89 63 / 20 10 0 0
SRQ 86 70 90 64 / 10 10 0 0
BKV 90 62 88 55 / 10 10 0 0
SPG 89 73 88 71 / 10 10 0 0
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
UPDATE...MROCZKA
AVIATION...RUDE
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1102 PM CDT SAT MAY 25 2013
.DISCUSSION...
ISSUED 830 PM CDT SAT MAY 25 2013
BAND OF SHOWERS AND ISOLATED THUNDERSTORMS WAS TRACKING ESE OVER
MAINLY THE EASTERN HALF OF THE FORECAST AREA. FAIRLY SIGNIFICANT
BAND OF FRONTOGENETICAL FORCING NOTED AT 850 MB THIS EVENING FROM
NW IL SE THRU EAST CENTRAL AND SOUTHEAST IL. THE AREA OF LIFT EVEN
STRETCHES FURTHER NW INTO PARTS OF CENTRAL THRU NW IOWA WHERE
ADDITIONAL SHOWERS AND THUNDERSTORMS WERE TRYING TO GET GOING THIS
EVENING. BASED ON THE LATEST HI-RES FORECASTS...IT APPEARS THE
BEST THREAT FOR ADDITIONAL DEVELOPMENT IN OUR AREA WILL BE ALIGNING
WITH THE TIGHT 850 MB THERMAL GRADIENT STRETCHING FROM NORTH CENTRAL
IOWA SOUTHEAST INTO CENTRAL IL. HRRR MODEL CONTINUES TO HOLD ON TO
THE SCATTERED SHOWERS BASICALLY IN THE SAME LOCATION WHERE RAIN HAS
BEE FALLING THIS EVENING...AND EXPANDS THE AREA LATER TONIGHT AS
THE LOW LEVEL JET INCREASES OUT TO OUR WEST FEEDING HIGH THETA-E
AIR NORTHEAST INTO THE MID-MISSISSIPPI VALLEY.
A STALLED FRONTAL BOUNDARY OVER PARTS OF SOUTHERN MISSOURI NW INTO
NEBRASKA WILL ONLY SLOWLY PUSH NORTHEAST THE NEXT COUPLE OF DAYS
WITH THE BETTER THREAT FOR RAIN ALONG AND ESPECIALLY TO THE NORTH
OF THE BOUNDARY. UNTIL THE FEATURE SHIFTS NORTH OF OUR AREA...AND
THAT IS NOT EXPECTED UNTIL AT LEAST EARLY TUESDAY MORNING...OCCASIONAL
SHOWERS AND THUNDERSTORMS WILL BE THE STORY THRU THE REST OF THE
HOLDIDAY WEEKEND. HAVE MADE SOME ADJUSTMENTS TO THE EARLY EVENING
TEMPS AND POPS IN A FEW AREAS OF EAST CENTRAL AND SE IL. THE UPDATED
ZFP SHOULD BE OUT BY 900 PM.
&&
.AVIATION...
ISSUED 1100 PM CDT SAT MAY 25 2013
LITTLE CHANGE FROM EARLIER THINKING...COVERAGE OF PRECIP LATER
TONIGHT AND ITS AFFECT ON CIGS/VSBYS THE MAIN CHALLENGE. OTHER
THAN SOME SCATTERED RAIN SHOWERS OCCURRING OVER PARTS OF EAST
CENTRAL IL LATE THIS EVENING...NOT A GREAT DEAL GOING ON. STARTING
TO SEE SOME LIGHT RETURNS ON RADAR OVER WEST CENTRAL IL THAT WAS
PUSHING SE AND MAY AFFECT SPI AND DEC WITH SOME LIGHT SHOWERS BUT
HAVE NOT SEEN MUCH...IF ANY REPORTS UNDERNEATH THOSE RETURNS YET.
WE HAVE HAD SOME BRIEF LOWERING OF CIGS/VSBYS TO MVFR AT TIMES IN
THE HEAVIER RAINS...BUT THOSE HAVE BEEN BRIEF AND WIDELY SCATTERED.
WILL CONTINUE WITH MAINLY VFR CIGS THRU THE PERIOD AND THEN TRY TO
TIME THE BEST COVERAGE OF RAIN AND THUNDER INTO OUR AREA LATE TONIGHT
AND ESPECIALLY SUNDAY MORNING. AFTER THAT...CONFIDENCE ON JUST WHERE
AND WHEN ADDITIONAL SHOWERS AND THUNDERSTORMS WILL OCCUR IS QUITE
LOW. FRONTAL BOUNDARY TO OUR SOUTH IS EXPECTED TO REMAIN THERE FOR
ANOTHER DAY KEEPING US IN AN EASTERLY FLOW THRU THE PERIOD. EAST
WINDS OF 10 TO 15 KTS TONIGHT WILL BECOME ESE AT 10 TO 15 KTS ON
SUNDAY.
SMITH
&&
.PREV DISCUSSION...
ISSUED 253 PM CDT SAT MAY 25 2013
HIGH PRESSURE RIDGE JUST TO THE EAST NOT QUITE STRONG ENOUGH TO
DAMPEN LEFTOVER MCS ACTIVITY MOVING INTO CENTRAL ILLINOIS THIS
AFTERNOON. WIDESPREAD SHOWERS AND ISOLATED THUNDER THROUGHOUT THE
EARLY AFTERNOON HOURS SLOWLY LOSING ITS STRENGTH AND THUNDER.
CLEARING SLOWLY MOVING TO THE EAST...THOUGH PLENTY OF -RA AND
SPRINKLES LIKELY. 4KM WRF DOING A FAIR JOB...IF NOT A FEW HOURS
BEHIND SCHEDULE. EXTRAPOLATING THE ERROR WOULD GIVE A BRIEF BREAK
WITH MORE SCATTERED ACTIVITY BEFORE THE NEXT ROUND. TODAYS WEATHER
EXPECTED TO CONTINUE THROUGH MONDAY BEFORE SLOWING ON TUESDAY.
MODELS IN PRETTY DECENT AGREEMENT THROUGH MID WEEK BEFORE
DIVERGING ON THE HANDLING OF THE UPPER WAVE PATTERN WITH THE TROF
OVER THE ERN HALF OF THE CONUS...AND ITS MOVEMENT AND TILT AS IT
PUSHES THE UPPER RIDGE OUT OF THE MIDWEST. TIMING ET AL IN
COMPLETE DISAGREEMENT BEYOND FH120.
SHORT TERM...TONIGHT THROUGH MONDAY...
PERIODIC SHOWERS AND THUNDERSTORMS LIKELY THROUGH MONDAY. WARM AIR
BUILDING UNDER THE RIDGE OVER THE PLAINS...AND A FRONT
DELINEATING THE BOUNDARY BETWEEN THE WARMER AIR TO THE SW AND THE
COOLER AIR OVER THE REGION ALMOST QUASI STATIONARY ALONG THE MISS
RIVER VALLEY FOR THE REMAINDER OF THE HOLIDAY WEEKEND. A SERIES
OF SHORT WAVES TOPPING THE RIDGE AND DIVING INTO ILX WILL KEEP THE
POPS IN PLACE THROUGH THE HOLIDAY WEEKEND. TEMPS CONTINUE TO
REMAIN MILD...EVEN THOUGH WARMING A COUPLE DEGREES EACH DAY...UNTIL THE
WARM FRONT FINALLY PASSES THROUGH THE AREA MON NIGHT/TUESDAY.
LONG TERM...TUESDAY THROUGH FRIDAY...
WARM FRONT LIFTING THROUGH THE REGION MON NIGHT AS THE ERN EDGE OF
THE RIDGE BREAKS DOWN AND PLENTY OF WARM AIR MOVES IN AT
MIDLEVELS. PRECIP SLOWLY REDUCING IN COVERAGE AND MUCH WARMER INTO
THE WORK WEEK. WESTERN TROF DIGS IN...AMPLIFYING THE WAVE PATTERN
OVER THE CONUS AND LEAVING THE UPPER MIDWEST IN SWRLY FLOW...AND
MUCH OF IL IN WEAK FLOW...IF ANY...UNDER THE BUILDING RIDGE. VERY
WARM MIDLEVELS AND THE GUIDANCE STILL BEING PULLED DOWN A BIT BY
CLIMATOLOGY INFLUENCE. HAVE BOOSTED TEMPS TO COMPENSATE...STILL MAY NOT BE
ENOUGH. RETURNING POPS ON THURS NIGHT/FRI GETTING DELAYED A BIT
MORE IN THIS RUN....AND STILL VERY MUCH IN DEBATE AS THE GFS AND
ECMWF DIVERGE QUITE A BIT WITH THE PROGRESSION OF THE WAVE PATTERN
AT DAY 7/8.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
836 PM CDT SAT MAY 25 2013
.DISCUSSION...
ISSUED 830 PM CDT SAT MAY 25 2013
BAND OF SHOWERS AND ISOLATED THUNDERSTORMS WAS TRACKING ESE OVER
MAINLY THE EASTERN HALF OF THE FORECAST AREA. FAIRLY SIGNIFICANT
BAND OF FRONTOGENETICAL FORCING NOTED AT 850 MB THIS EVENING FROM
NW IL SE THRU EAST CENTRAL AND SOUTHEAST IL. THE AREA OF LIFT EVEN
STRETCHES FURTHER NW INTO PARTS OF CENTRAL THRU NW IOWA WHERE
ADDITIONAL SHOWERS AND THUNDERSTORMS WERE TRYING TO GET GOING THIS
EVENING. BASED ON THE LATEST HI-RES FORECASTS...IT APPEARS THE
BEST THREAT FOR ADDITIONAL DEVELOPMENT IN OUR AREA WILL BE ALIGNING
WITH THE TIGHT 850 MB THERMAL GRADIENT STRETCHING FROM NORTH CENTRAL
IOWA SOUTHEAST INTO CENTRAL IL. HRRR MODEL CONTINUES TO HOLD ON TO
THE SCATTERED SHOWERS BASICALLY IN THE SAME LOCATION WHERE RAIN HAS
BEE FALLING THIS EVENING...AND EXPANDS THE AREA LATER TONIGHT AS
THE LOW LEVEL JET INCREASES OUT TO OUR WEST FEEDING HIGH THETA-E
AIR NORTHEAST INTO THE MID-MISSISSIPPI VALLEY.
A STALLED FRONTAL BOUNDARY OVER PARTS OF SOUTHERN MISSOURI NW INTO
NEBRASKA WILL ONLY SLOWLY PUSH NORTHEAST THE NEXT COUPLE OF DAYS
WITH THE BETTER THREAT FOR RAIN ALONG AND ESPECIALLY TO THE NORTH
OF THE BOUNDARY. UNTIL THE FEATURE SHIFTS NORTH OF OUR AREA...AND
THAT IS NOT EXPECTED UNTIL AT LEAST EARLY TUESDAY MORNING...OCCASIONAL
SHOWERS AND THUNDERSTORMS WILL BE THE STORY THRU THE REST OF THE
HOLDIDAY WEEKEND. HAVE MADE SOME ADJUSTMENTS TO THE EARLY EVENING
TEMPS AND POPS IN A FEW AREAS OF EAST CENTRAL AND SE IL. THE UPDATED
ZFP SHOULD BE OUT BY 900 PM.
SMITH
&&
.AVIATION...
ISSUED 600 PM CDT SAT MAY 25 2013
MAIN FORECAST CONCERN THIS PERIOD WILL BE COVERAGE OF SHOWERS AND
THUNDERSTORMS AND THEIR AFFECT ON CIGS AND VSBYS.
FRONTAL BOUNDARY WELL TO THE SOUTH OF OUR AREA LATE THIS AFTERNOON
WITH SCATTERED SHOWERS AND ISOLD TSRA OCCURRING IN A NW-SE ARC NORTH
OF THE BOUNDARY ACRS OUR AREA. WILL PROBABLY SEE A BREAK FROM THE
RAIN MOST AREAS EARLY THIS EVENING WITH MORE WIDESPREAD COVERAGE
DEVELOPING OUT TO OUR NW LATER THIS EVENING AND THEN MOVING IN LATE
TONIGHT INTO SUNDAY MORNING. JUST WHERE THE BETTER COVERAGE WILL
BE WITH THIS NEXT ROUND OF RAIN IS STILL NOT CERTAIN AT THIS POINT.
MANY MODELS POINT TO AREAS FROM SOUTHERN IOWA...NE MO INTO WEST
CENTRAL/SW IL...HOWEVER...MOST OF THE CURRENT ACTIVITY IS WELL NORTH
OF THAT LOCATION...AT LEAST FOR NOW. WILL CONTINUE WITH THE CURRENT
IDEA OF VCSH EARLY THIS EVENING AND THEN BRINGING IN SOME -RA WITH
VCTS...BUT WILL PUSH THE TIMING BACK AS IT APPEARS THE BETTER THREAT
WILL HOLD OFF UNTIL AFTR MIDNIGHT BASED ON THE LATEST HI-RES MODEL
SOLUTIONS. FORECAST SOUNDINGS STILL SUGGEST MAINLY LOWER VFR CIGS
THRU THE PERIOD BUT WE SHOULD SEE SOME TEMPO MVFR OR EVEN LOWER
CIGS WITH SOME OF THE HEAVIER SHOWERS AND THUNDERSTORMS LATER
TONIGHT...BUT WHERE THAT IS GOING TO OCCUR IS NOT CERTAIN AT THIS
TIME.
THE SHOWER THREAT WILL CONTINUE THRU THE MORNING ON SUNDAY BEFORE
WE SEE ANOTHER TEMPORARY BREAK IN THE AFTN BEFORE ANOTHER ROUND OF
SHOWERS MOVES IN LATE IN THE DAY OR EVENING. SFC WINDS WILL REMAIN
FROM AN EASTERLY DIRECTION TONIGHT AT AROUND 10 KTS...AND EAST TO
SOUTHEAST AT 10 TO 15 KTS ON SUNDAY.
SMITH
&&
.PREV DISCUSSION...
ISSUED 253 PM CDT SAT MAY 25 2013
HIGH PRESSURE RIDGE JUST TO THE EAST NOT QUITE STRONG ENOUGH TO
DAMPEN LEFTOVER MCS ACTIVITY MOVING INTO CENTRAL ILLINOIS THIS
AFTERNOON. WIDESPREAD SHOWERS AND ISOLATED THUNDER THROUGHOUT THE
EARLY AFTERNOON HOURS SLOWLY LOSING ITS STRENGTH AND THUNDER.
CLEARING SLOWLY MOVING TO THE EAST...THOUGH PLENTY OF -RA AND
SPRINKLES LIKELY. 4KM WRF DOING A FAIR JOB...IF NOT A FEW HOURS
BEHIND SCHEDULE. EXTRAPOLATING THE ERROR WOULD GIVE A BRIEF BREAK
WITH MORE SCATTERED ACTIVITY BEFORE THE NEXT ROUND. TODAYS WEATHER
EXPECTED TO CONTINUE THROUGH MONDAY BEFORE SLOWING ON TUESDAY.
MODELS IN PRETTY DECENT AGREEMENT THROUGH MID WEEK BEFORE
DIVERGING ON THE HANDLING OF THE UPPER WAVE PATTERN WITH THE TROF
OVER THE ERN HALF OF THE CONUS...AND ITS MOVEMENT AND TILT AS IT
PUSHES THE UPPER RIDGE OUT OF THE MIDWEST. TIMING ET AL IN
COMPLETE DISAGREEMENT BEYOND FH120.
SHORT TERM...TONIGHT THROUGH MONDAY...
PERIODIC SHOWERS AND THUNDERSTORMS LIKELY THROUGH MONDAY. WARM AIR
BUILDING UNDER THE RIDGE OVER THE PLAINS...AND A FRONT
DELINEATING THE BOUNDARY BETWEEN THE WARMER AIR TO THE SW AND THE
COOLER AIR OVER THE REGION ALMOST QUASI STATIONARY ALONG THE MISS
RIVER VALLEY FOR THE REMAINDER OF THE HOLIDAY WEEKEND. A SERIES
OF SHORT WAVES TOPPING THE RIDGE AND DIVING INTO ILX WILL KEEP THE
POPS IN PLACE THROUGH THE HOLIDAY WEEKEND. TEMPS CONTINUE TO
REMAIN MILD...EVEN THOUGH WARMING A COUPLE DEGREES EACH DAY...UNTIL THE
WARM FRONT FINALLY PASSES THROUGH THE AREA MON NIGHT/TUESDAY.
LONG TERM...TUESDAY THROUGH FRIDAY...
WARM FRONT LIFTING THROUGH THE REGION MON NIGHT AS THE ERN EDGE OF
THE RIDGE BREAKS DOWN AND PLENTY OF WARM AIR MOVES IN AT
MIDLEVELS. PRECIP SLOWLY REDUCING IN COVERAGE AND MUCH WARMER INTO
THE WORK WEEK. WESTERN TROF DIGS IN...AMPLIFYING THE WAVE PATTERN
OVER THE CONUS AND LEAVING THE UPPER MIDWEST IN SWRLY FLOW...AND
MUCH OF IL IN WEAK FLOW...IF ANY...UNDER THE BUILDING RIDGE. VERY
WARM MIDLEVELS AND THE GUIDANCE STILL BEING PULLED DOWN A BIT BY
CLIMATOLOGY INFLUENCE. HAVE BOOSTED TEMPS TO COMPENSATE...STILL MAY NOT BE
ENOUGH. RETURNING POPS ON THURS NIGHT/FRI GETTING DELAYED A BIT
MORE IN THIS RUN....AND STILL VERY MUCH IN DEBATE AS THE GFS AND
ECMWF DIVERGE QUITE A BIT WITH THE PROGRESSION OF THE WAVE PATTERN
AT DAY 7/8.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1019 PM EDT SAT MAY 25 2013
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW
&&
.SYNOPSIS...
ISSUED AT 233 PM EDT SAT MAY 25 2013
A WARM FRONT WILL LIFT NORTHEAST ACROSS CENTRAL INDIANA LATE SUNDAY
THROUGH MONDAY EVENING. THE FRONT AND UPPER LEVEL DISTURBANCES WILL
HELP BRING SHOWERS AND THUNDERSTORMS TO CENTRAL INDIANA THIS
MEMORIAL DAY WEEKEND AND INTO EARLY NEXT WEEK. THE WARM FRONTAL
PASSAGE WILL ALSO BRING A RETURN TO NORMAL TEMPERATURES BY MONDAY
AND ABOVE NORMAL TEMPERATURES IN THE 80S BY TUESDAY. THUNDERSTORM
CHANCES WILL RETURN BY SATURDAY FOLLOWING A DRY MID TO LATE WEEK.
&&
.NEAR TERM /OVERNIGHT/...
ISSUED AT 1012 PM EDT SAT MAY 25 2013
RAIN SHOWERS CURRENTLY ACROSS MUCH OF THE SOUTHWEST HALF OF THE
FORECAST AREA WITH LIGHTER SHOWERS/SPRINKLES FURTHER NORTHEAST.
TEMPS WERE IN THE 50S AT 02Z.
UPPER LEVEL SHORTWAVE WILL TRACK ACROSS THE REGION OVER THE NEXT
FEW HOURS MAINTAINING THE RAIN SHOWERS THROUGH AT LEAST 06Z. THE
GREATEST COVERAGE TO RAINFALL WILL BE SOUTHWEST OF A LAFAYETTE-
INDY METRO-SEYMOUR LINE WHERE DEWPOINTS AND LOW LEVEL MOISTURE ARE
A BIT MORE PLENTIFUL. ONCE THE SHORTWAVE SHIFTS OFF TO THE
SOUTHEAST LATE TONIGHT...EXPECT COVERAGE TO SHOWERS TO DIMINISH
ACROSS MUCH OF THE AREA AND THE CURRENT HRRR SUPPORTS THIS
THINKING. FORECAST LOWS STILL LOOK REACHABLE WITH MANY AREAS
FALLING INTO THE UPPER 40S AND LOWER 50S.
ZONE AND GRID UPDATES OUT.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
ISSUED AT 233 PM EDT SAT MAY 25 2013
MAIN CHALLENGE FOR MEMORIAL DAY WEEKEND THROUGH TUESDAY WILL BE POPS
AS SHOWERS AND THUNDERSTORMS WILL PLACE OUTDOOR ACTIVITIES IN
JEOPARDY ACROSS CENTRAL INDIANA.
MODELS IN GOOD AGREEMENT ON BRINGING A SWATH OF QPF ACROSS CENTRAL
INDIANA ON SUNDAY AS WARM FRONT DRIFTS NORTHEAST TO THE MIDDLE
MISSISSIPPI VALLEY...AND FRONTOGENESIS AT 850 MILLIBARS AND WARM AIR
ADVECTION CONTINUE NORTHEAST OF THE FRONT ACROSS CENTRAL INDIANA.
ALSO...MORE UPPER WAVES WILL MOVE ACROSS AHEAD OF THE APPROACHING AND
WEAKENING UPPER RIDGE. THUS...WILL RAISE POPS TO GOOD CHANCE OR
BETTER WITH LIKELY POPS ALONG AND NEAR A CORRIDOR FROM IND-LAF AFTER
18Z. LOOKING AT MOST UNSTABLE CAPE PROGS...WOULD NOT RULE OUT
THUNDER ESPECIALLY SOUTHWEST OF IND...BUT WILL GO AHEAD AND INCLUDE
ISOLATED THUNDER ACROSS ALL COUNTIES. SUNDAY NIGHT AND MONDAY LOOK
TO BE THE MOST ACTIVE PERIOD AS THE WARM FRONT MOVES THROUGH WITH
HIGHEST POPS FROM IND AND NORTH...WHERE CHANCES WILL BE IN THE
LIKELY CATEGORY. MORE UNSTABLE AIR ALSO ARRIVES WITH THE FRONT...SO
WENT WITH THUNDER ALL ZONES FROM SUNDAY NIGHT ON. POPS WILL BE
DECREASING FROM SOUTH TO NORTH BEHIND THE FRONT BY MONDAY NIGHT WITH
A DRY FORECAST FAR SOUTH ON TUESDAY AS THE UPPER RIDGE MOVES ACROSS
THE OHIO VALLEY.
TEMPERATURES WILL BE CLIMBING EACH DAY AS THE WARM FRONT APPROACHES
AND IN ITS WAKE. BELOW NORMAL TEMPERATURES PER MODEL BLEND AND
CONSALL LOOK GOOD FOR SUNDAY WITH HIGHS ONLY IN THE MID 60S NORTH TO
THE LOWER 70S SOUTH. BY MONDAY WITH THE FRONT MOVING
THROUGH...SHOULD BE A STRONGER TEMPERATURE GRADIENT. HIGHS EXPECTED
TO WARM TO NEAR NORMAL IN THE UPPER 60S NORTHEAST TO THE UPPER 70S
SOUTHWEST. FINALLY...HIGHS WILL BE ABOVE NORMAL BY TUESDAY WITH
CENTRAL INDIANA IN THE WARM SECTOR. AFTERNOON HIGHS IN THE LOWER 80S
PER BLEND LOOK GOOD.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
ISSUED AT 212 PM EDT SAT MAY 25 2013
MODELS ARE CLOSE ENOUGH THAT THE ALLBLEND INITIALIZATION CAN BE USED
FOR MOST ITEMS.
UPPER RIDGE WILL BE IN CONTROL THROUGH MOST OF THE PERIOD...AND THIS
SHOULD KEEP A CAP ON CONVECTION. MODELS CONTINUE TO FLIP-FLOP ON
WHETHER RIDGE WILL BREAK DOWN ENOUGH FOR SOME CONVECTION ON FRIDAY.
RATHER THAN FLIP-FLOP WITH THIS FORECAST...WILL KEEP IT CONSISTENT
AND GO DRY THROUGH FRIDAY NIGHT. RIDGE LOOKS TO BREAK DOWN ENOUGH ON
SATURDAY FOR CHANCE POPS.
UPPER RIDGE WILL ALLOW WARM TEMPERATURES THROUGH THE PERIOD.
&&
.AVIATION /DISCUSSION FOR THE 26/0300Z TAF UPDATE/...
ISSUED AT 1018 PM EDT SAT MAY 25 2013
UPDATE...
NO CHANGES.
PREVIOUS DISCUSSION...
WIDESPREAD RAIN SHOWERS CONTINUE TO AFFECT TAF SITES.
HOWEVER...CONDITIONS ARE EXPECTED TO STAY AT VFR CATEGORY WITH
BRIEF DETERIORATION TO MVFR IN HEAVIER RAIN SHOWERS. AFTER A LULL
IN ACTIVITY LATE TONIGHT...TRENDED ON WETTER SIDE STARTING AROUND
MID TO LATE MORNING TOMORROW AS A WARM FRONT MOVES CLOSER TO
CENTRAL INDIANA. CHANCES FOR MVFR CONDITIONS WILL BE HIGHER
TOMORROW WITH REDUCED CEILINGS AND VISIBILITIES. LIGHT AND
VARIABLE WINDS WILL EVENTUALLY BECOME SOUTHEASTERLY TONIGHT AT 5
TO 10 KTS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...MK
NEAR TERM...RYAN
SHORT TERM...MK
LONG TERM....50
AVIATION...TDUD
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
1012 PM EDT SAT MAY 25 2013
.UPDATE...
THE NEAR TERM SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 233 PM EDT SAT MAY 25 2013
A WARM FRONT WILL LIFT NORTHEAST ACROSS CENTRAL INDIANA LATE SUNDAY
THROUGH MONDAY EVENING. THE FRONT AND UPPER LEVEL DISTURBANCES WILL
HELP BRING SHOWERS AND THUNDERSTORMS TO CENTRAL INDIANA THIS
MEMORIAL DAY WEEKEND AND INTO EARLY NEXT WEEK. THE WARM FRONTAL
PASSAGE WILL ALSO BRING A RETURN TO NORMAL TEMPERATURES BY MONDAY
AND ABOVE NORMAL TEMPERATURES IN THE 80S BY TUESDAY. THUNDERSTORM
CHANCES WILL RETURN BY SATURDAY FOLLOWING A DRY MID TO LATE WEEK.
&&
.NEAR TERM /OVERNIGHT/...
ISSUED AT 1012 PM EDT SAT MAY 25 2013
RAIN SHOWERS CURRENTLY ACROSS MUCH OF THE SOUTHWEST HALF OF THE
FORECAST AREA WITH LIGHTER SHOWERS/SPRINKLES FURTHER NORTHEAST.
TEMPS WERE IN THE 50S AT 02Z.
UPPER LEVEL SHORTWAVE WILL TRACK ACROSS THE REGION OVER THE NEXT
FEW HOURS MAINTAINING THE RAIN SHOWERS THROUGH AT LEAST 06Z. THE
GREATEST COVERAGE TO RAINFALL WILL BE SOUTHWEST OF A LAFAYETTE-
INDY METRO-SEYMOUR LINE WHERE DEWPOINTS AND LOW LEVEL MOISTURE ARE
A BIT MORE PLENTIFUL. ONCE THE SHORTWAVE SHIFTS OFF TO THE
SOUTHEAST LATE TONIGHT...EXPECT COVERAGE TO SHOWERS TO DIMINISH
ACROSS MUCH OF THE AREA AND THE CURRENT HRRR SUPPORTS THIS
THINKING. FORECAST LOWS STILL LOOK REACHABLE WITH MANY AREAS
FALLING INTO THE UPPER 40S AND LOWER 50S.
ZONE AND GRID UPDATES OUT.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
ISSUED AT 233 PM EDT SAT MAY 25 2013
MAIN CHALLENGE FOR MEMORIAL DAY WEEKEND THROUGH TUESDAY WILL BE POPS
AS SHOWERS AND THUNDERSTORMS WILL PLACE OUTDOOR ACTIVITIES IN
JEOPARDY ACROSS CENTRAL INDIANA.
MODELS IN GOOD AGREEMENT ON BRINGING A SWATH OF QPF ACROSS CENTRAL
INDIANA ON SUNDAY AS WARM FRONT DRIFTS NORTHEAST TO THE MIDDLE
MISSISSIPPI VALLEY...AND FRONTOGENESIS AT 850 MILLIBARS AND WARM AIR
ADVECTION CONTINUE NORTHEAST OF THE FRONT ACROSS CENTRAL INDIANA.
ALSO...MORE UPPER WAVES WILL MOVE ACROSS AHEAD OF THE APPROACHING AND
WEAKENING UPPER RIDGE. THUS...WILL RAISE POPS TO GOOD CHANCE OR
BETTER WITH LIKELY POPS ALONG AND NEAR A CORRIDOR FROM IND-LAF AFTER
18Z. LOOKING AT MOST UNSTABLE CAPE PROGS...WOULD NOT RULE OUT
THUNDER ESPECIALLY SOUTHWEST OF IND...BUT WILL GO AHEAD AND INCLUDE
ISOLATED THUNDER ACROSS ALL COUNTIES. SUNDAY NIGHT AND MONDAY LOOK
TO BE THE MOST ACTIVE PERIOD AS THE WARM FRONT MOVES THROUGH WITH
HIGHEST POPS FROM IND AND NORTH...WHERE CHANCES WILL BE IN THE
LIKELY CATEGORY. MORE UNSTABLE AIR ALSO ARRIVES WITH THE FRONT...SO
WENT WITH THUNDER ALL ZONES FROM SUNDAY NIGHT ON. POPS WILL BE
DECREASING FROM SOUTH TO NORTH BEHIND THE FRONT BY MONDAY NIGHT WITH
A DRY FORECAST FAR SOUTH ON TUESDAY AS THE UPPER RIDGE MOVES ACROSS
THE OHIO VALLEY.
TEMPERATURES WILL BE CLIMBING EACH DAY AS THE WARM FRONT APPROACHES
AND IN ITS WAKE. BELOW NORMAL TEMPERATURES PER MODEL BLEND AND
CONSALL LOOK GOOD FOR SUNDAY WITH HIGHS ONLY IN THE MID 60S NORTH TO
THE LOWER 70S SOUTH. BY MONDAY WITH THE FRONT MOVING
THROUGH...SHOULD BE A STRONGER TEMPERATURE GRADIENT. HIGHS EXPECTED
TO WARM TO NEAR NORMAL IN THE UPPER 60S NORTHEAST TO THE UPPER 70S
SOUTHWEST. FINALLY...HIGHS WILL BE ABOVE NORMAL BY TUESDAY WITH
CENTRAL INDIANA IN THE WARM SECTOR. AFTERNOON HIGHS IN THE LOWER 80S
PER BLEND LOOK GOOD.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
ISSUED AT 212 PM EDT SAT MAY 25 2013
MODELS ARE CLOSE ENOUGH THAT THE ALLBLEND INITIALIZATION CAN BE USED
FOR MOST ITEMS.
UPPER RIDGE WILL BE IN CONTROL THROUGH MOST OF THE PERIOD...AND THIS
SHOULD KEEP A CAP ON CONVECTION. MODELS CONTINUE TO FLIP-FLOP ON
WHETHER RIDGE WILL BREAK DOWN ENOUGH FOR SOME CONVECTION ON FRIDAY.
RATHER THAN FLIP-FLOP WITH THIS FORECAST...WILL KEEP IT CONSISTENT
AND GO DRY THROUGH FRIDAY NIGHT. RIDGE LOOKS TO BREAK DOWN ENOUGH ON
SATURDAY FOR CHANCE POPS.
UPPER RIDGE WILL ALLOW WARM TEMPERATURES THROUGH THE PERIOD.
&&
.AVIATION /DISCUSSION FOR THE 26/0000Z TAF ISSUANCE/...
ISSUED AT 701 PM EDT SAT MAY 25 2013
WIDESPREAD RAIN SHOWERS CONTINUE TO AFFECT TAF SITES.
HOWEVER...CONDITIONS ARE EXPECTED TO STAY AT VFR CATEGORY WITH
BRIEF DETERIORATION TO MVFR IN HEAVIER RAIN SHOWERS. AFTER A LULL
IN ACTIVITY LATE TONIGHT...TRENDED ON WETTER SIDE STARTING AROUND
MID TO LATE MORNING TOMORROW AS A WARM FRONT MOVES CLOSER TO
CENTRAL INDIANA. CHANCES FOR MVFR CONDITIONS WILL BE HIGHER
TOMORROW WITH REDUCED CEILINGS AND VISIBILITIES. LIGHT AND
VARIABLE WINDS WILL EVENTUALLY BECOME SOUTHEASTERLY TONIGHT AT 5
TO 10 KTS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...MK
NEAR TERM...RYAN
SHORT TERM...MK
LONG TERM....50
AVIATION...TDUD
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
421 AM EDT FRI MAY 24 2013
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 225 AM EDT FRI MAY 24 2013
STRONG AND COOL CANADIAN HIGH PRESSURE CENTERED OVER THE GREAT
LAKES WILL BUILD ACROSS THE OHIO VALLEY THE NEXT FEW DAYS. THIS
WILL BRING BELOW NORMAL TEMPERATURES BUT DRY WEATHER FOR INDIANA
THROUGH SATURDAY NIGHT.
AS THE HIGH BEGINS TO DRIFT EAST ON SUNDAY...A WARM FRONT WILL
APPROACH INDIANA FROM THE SOUTHWEST...BRING MORE CLOUDS...WARMER
TEMPERATURES AND SMALL CHANCES FOR RAIN ON SUNDAY AFTERNOON
THROUGH MONDAY.
TEMPERATURES WILL RETURN TO NEAR NORMAL MEMORIAL DAY AND ABOVE
NORMAL BY MIDWEEK NEXT WEEK. THUNDERSTORM CHANCES WILL ALSO RETURN
NEXT WEEK AS GULF MOISTURE SPREADS NORTH ACROSS THE OHIO VALLEY.
&&
.NEAR TERM /TODAY/...
ISSUED AT 225 AM EDT FRI MAY 24 2013
SURFACE ANALYSIS EARLY THIS MORNING SHOWS A LARGE AREA OF HIGH
PRESSURE CENTERED OVER THE NORTH WOODS OF WISCONSIN AND LAKE
SUPERIOR. COOL NORTH FLOW WAS IN PLACE ACROSS INDIANA. IR PICTURES
SHOWED STRATOCU EXITING THE AREA TO THE EAST. THE WESTERN 1/2 OF
THE OF THE STATE HAD ALREADY BECOME CLEAR.
MAIN FORECAST CHALLENGE TODAY WILL BE TEMPS. FORECAST SOUNDINGS
AND TIME HEIGHTS REMAIN QUITE DRY. FORECAST SOUNDINGS SHOW
CONVECTIVE TEMPS IN THE UPPER 70S...AND GIVEN OUR 850MB TEMPS
AROUND 3-5 DEGREES AMID COLD AIR ADVECTION...WE WILL NOT GET THAT
WARM. THUS MOSTLY SUNNY SKIES EXPECTED TODAY.
BACK TO TEMPS...GIVEN OUR 850MB TEMPS AND THE COOL START AND
ONGOING COLD AIR ADVECTION WILL TREND HIGHS AT OR BELOW MAVMOS.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
ISSUED AT 225 AM EDT FRI MAY 24 2013
MAIN FORECAST CHALLENGE DURING THIS PERIOD WILL BE POPS ON SUNDAY
AND SUNDAY NIGHT.
LITTLE CHANGE IS EXPECTED THROUGH SATURDAY NIGHT WITH THE ONGOING
WEATHER. THE PREVIOUSLY MENTIONED LARGE ARE OF HIGH PRESSURE WILL
REMAIN ACROSS THE GREAT LAKES AND INDIANA...CONTINUING TO DOMINATE
TH REGIONS WEATHER...PROVIDING MOSTLY CLEAR...COOL NIGHTS AND
MOSTLY SUNNY AND COOL DAYS.
ECMWF AND GFS CONTINUE TO BUILD A STRONG RIDGE OVER THE PLAINS
STATES ALOFT WITH NORTHWEST FLOW ON THE LEE SIDE OF THE RIDGE
SPILLING INTO INDIANA AND THE OHIO VALLEY. BY SATURDAY...SOME WARM
AIR ADVECTION BEGINS IN SOUTHWEST INDIANA...HOWEVER THE COLD AIR
LOOKS TO REMAIN IN PLACE THROUGH THE DAY AS 850MB TEMPS LOOK TO
HOLD NEAR 5C THROUGH THE DAY. THUS WITH A FEW MORE HIGH AND MID CLOUDS
EXPECTED ON SATURDAY WILL TREND HIGHS CLOSE TO EXPECTED PERSISTENCE.
GFS INDICATES A SHORT WAVE PUSHING THROUGH THE NORTHWEST FLOW ACROSS
INDIANA ON SUNDAY AFTERNOON AS WARM AIR ADVECTION CONTINUES IN THE
LOWER LEVELS. GULF MOISTURE REMAINS CUT OFF AND DEW POINTS LOOK TO
REMAIN IN THE RELATIVELY DRY 40S. GFS 300K ISENTROPIC SURFACE
SHOWS SOME LIFT ACROSS THE AREA ON LATE SUNDAY AFTERNOON AND INTO
SUNDAY NIGHT AS SPECIFIC HUMIDITIES RISE TO NEAR 7G/KG. FORECAST
SOUNDINGS AND TIME HEIGHTS HINT AT MORE MOISTURE AVAILABLE IN THE
COLUMN HOWEVER. THUS CONFIDENCE IN ANY RAIN REMAINS LOW AND WILL
CONTINUE TO CARRY A LOW CHC POP DURING THIS TIME PERIOD. AS FOR
TEMPS WILL CONTINUE TO HOLD VALUES AT OR BELOW MAVMOS GIVEN THE
ADDITIONAL CLOUD COVER EXPECTED ACROSS THE AREA...ALONG WITH THE
LOW PRECIPITATION CHANCES.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
ISSUED AT 152 AM EDT THU MAY 23 2013
ENSEMBLES IN GOOD AGREEMENT WITH THE LONG WAVE FEATURES DURING THIS
PERIOD. UPPER RIDGE CURRENTLY OVER THE PLAINS IS EXPECTED TO
GRADUALLY SHIFT EAST INTO THE MIDWEST AND OHIO VALLEY BY THE MIDDLE
OF NEXT WEEK. APPEARS THERE IS A POTENTIAL FOR EMBEDDED SHORT WAVE
TROUGHS TO RIDE THROUGH THE RIDGE...AT LEAST ON MONDAY AND TUESDAY.
WILL CONTINUE WITH CHANCE POPS AT THOSE TIMES.
BY NEXT WEDNESDAY AND THURSDAY...ENSEMBLES SUGGEST THE UPPER RIDGE
WILL BUILD MORE AGGRESSIVELY OVER THE AREA AS DEEP TROUGHING DEVELOPS
OVER THE WEST COAST AND ROCKIES. THIS SHOULD HELP TO CAP OFF
PRECIPITATION CHANCES LATER NEXT WEEK...WITH THE ENSEMBLES
SUGGESTING LITTLE THREAT FOR PRECIPITATION AFTER TUESDAY. WILL GO
DRY FOR NEXT WEDNESDAY AND THURSDAY.
&&
.AVIATION /DISCUSSION FOR THE 240900Z KIND TAF UPDATE/...
ISSUED AT 421 AM EDT FRI MAY 24 2013
AREA OF MVFR CEILINGS AROUND 020 CONTINUE TO DRIFT SOUTH...AFFECTING
THE KIND TERMINAL. EXTRAPOLATION OF THE BACK EDGE SUGGESTS THESE
CEILINGS WILL SCATTER OUT AT KIND AROUND 241100Z. THERE WAS SOME
POCKETS OF IFR CEILINGS AS WELL...BUT THESE SEEM TO HAVE DISSIPATED
FOR THE MOST PART BASED ON UPSTREAM OBSERVATIONS.
PREVIOUS DISCUSSION FOLLOWS.
POCKETS OF MVFR CEILINGS TO PERSIST AT KBMG AND KIND FOR THE NEXT
FEW HOURS...OTHERWISE VFR CONDITIONS EXPECTED.
STRATOCU DECK CONTINUES TO ERODE FROM THE NORTHWEST...WITH KHUF AND
KLAF NOW MAINLY CLEAR WITH PREDOMINANT CEILING UP TO 3500-4000FT AT
BOTH KBMG AND KIND. RAP DATA INDICATING THAT A N/NE FLOW WILL KEEP
AXIS OF DEEPER MOISTURE THROUGH THE BOUNDARY LAYER ALIGNED ACROSS
THE REGION FOR THE NEXT 3-6 HOURS. CURRENT SATELLITE IMAGERY
SUPPORTS THIS THINKING AS AREA OF LOWER CLOUDS DRIFTING SOUTH ACROSS
NORTHERN INDIANA. WILL KEEP CLOUDS IN AT KBMG AND KIND FOR THE NEXT
FEW HOURS WITH CLEARING THEREAFTER AS DRIER AIR ADVECTS INTO THE
REGION WITH THE HIGH. NORTHERLY WINDS AT 10-15KTS CURRENTLY WILL
DIMINISH TO 5-10KTS LATE.
THE HIGH WILL EXPAND ACROSS THE OHIO VALLEY WITH QUIET WEATHER
TODAY. PRESENCE OF THE DEPARTING LOW LEVEL THERMAL TROUGH INTO THE
AFTERNOON MAY BE JUST ENOUGH TO GENERATE A FEW CU AT KIND.
OTHERWISE...ANTICIPATE CLEAR SKIES AND NORTHERLY WINDS TO NEAR 10KTS
ALL DAY. MAY START TO SEE SOME THIN CIRRUS DRIFT INTO THE REGION
TONIGHT AS IT SPILLS OVER TOP OF THE UPPER RIDGE OVER THE CENTRAL
PLAINS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...PUMA
NEAR TERM...PUMA
SHORT TERM...PUMA
LONG TERM....JAS
AVIATION...RYAN/JAS
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
225 AM EDT FRI MAY 24 2013
.UPDATE...
THE SYNOPSIS...NEAR TERM...SHORT TERM AND LONG TERM SECTIONS HAVE
BEEN UPDATED BELOW
&&
.SYNOPSIS...
ISSUED AT 225 AM EDT FRI MAY 24 2013
STRONG AND COOL CANADIAN HIGH PRESSURE CENTERED OVER THE GREAT
LAKES WILL BUILD ACROSS THE OHIO VALLEY THE NEXT FEW DAYS. THIS
WILL BRING BELOW NORMAL TEMPERATURES BUT DRY WEATHER FOR INDIANA
THROUGH SATURDAY NIGHT.
AS THE HIGH BEGINS TO DRIFT EAST ON SUNDAY...A WARM FRONT WILL
APPROACH INDIANA FROM THE SOUTHWEST...BRING MORE CLOUDS...WARMER
TEMPERATURES AND SMALL CHANCES FOR RAIN ON SUNDAY AFTERNOON
THROUGH MONDAY.
TEMPERATURES WILL RETURN TO NEAR NORMAL MEMORIAL DAY AND ABOVE
NORMAL BY MIDWEEK NEXT WEEK. THUNDERSTORM CHANCES WILL ALSO RETURN
NEXT WEEK AS GULF MOISTURE SPREADS NORTH ACROSS THE OHIO VALLEY.
&&
.NEAR TERM /TODAY/...
ISSUED AT 225 AM EDT FRI MAY 24 2013
SURFACE ANALYSIS EARLY THIS MORNING SHOWS A LARGE AREA OF HIGH
PRESSURE CENTERED OVER THE NORTH WOODS OF WISCONSIN AND LAKE
SUPERIOR. COOL NORTH FLOW WAS IN PLACE ACROSS INDIANA. IR PICTURES
SHOWED STRATOCU EXITING THE AREA TO THE EAST. THE WESTERN 1/2 OF
THE OF THE STATE HAD ALREADY BECOME CLEAR.
MAIN FORECAST CHALLENGE TODAY WILL BE TEMPS. FORECAST SOUNDINGS
AND TIME HEIGHTS REMAIN QUITE DRY. FORECAST SOUNDINGS SHOW
CONVECTIVE TEMPS IN THE UPPER 70S...AND GIVEN OUR 850MB TEMPS
AROUND 3-5 DEGREES AMID COLD AIR ADVECTION...WE WILL NOT GET THAT
WARM. THUS MOSTLY SUNNY SKIES EXPECTED TODAY.
BACK TO TEMPS...GIVEN OUR 850MB TEMPS AND THE COOL START AND
ONGOING COLD AIR ADVECTION WILL TREND HIGHS AT OR BELOW MAVMOS.
&&
.SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
ISSUED AT 225 AM EDT FRI MAY 24 2013
MAIN FORECAST CHALLENGE DURING THIS PERIOD WILL BE POPS ON SUNDAY
AND SUNDAY NIGHT.
LITTLE CHANGE IS EXPECTED THROUGH SATURDAY NIGHT WITH THE ONGOING
WEATHER. THE PREVIOUSLY MENTIONED LARGE ARE OF HIGH PRESSURE WILL
REMAIN ACROSS THE GREAT LAKES AND INDIANA...CONTINUING TO DOMINATE
TH REGIONS WEATHER...PROVIDING MOSTLY CLEAR...COOL NIGHTS AND
MOSTLY SUNNY AND COOL DAYS.
ECMWF AND GFS CONTINUE TO BUILD A STRONG RIDGE OVER THE PLAINS
STATES ALOFT WITH NORTHWEST FLOW ON THE LEE SIDE OF THE RIDGE
SPILLING INTO INDIANA AND THE OHIO VALLEY. BY SATURDAY...SOME WARM
AIR ADVECTION BEGINS IN SOUTHWEST INDIANA...HOWEVER THE COLD AIR
LOOKS TO REMAIN IN PLACE THROUGH THE DAY AS 850MB TEMPS LOOK TO
HOLD NEAR 5C THROUGH THE DAY. THUS WITH A FEW MORE HIGH AND MID CLOUDS
EXPECTED ON SATURDAY WILL TREND HIGHS CLOSE TO EXPECTED PERSISTENCE.
GFS INDICATES A SHORT WAVE PUSHING THROUGH THE NORTHWEST FLOW ACROSS
INDIANA ON SUNDAY AFTERNOON AS WARM AIR ADVECTION CONTINUES IN THE
LOWER LEVELS. GULF MOISTURE REMAINS CUT OFF AND DEW POINTS LOOK TO
REMAIN IN THE RELATIVELY DRY 40S. GFS 300K ISENTROPIC SURFACE
SHOWS SOME LIFT ACROSS THE AREA ON LATE SUNDAY AFTERNOON AND INTO
SUNDAY NIGHT AS SPECIFIC HUMIDITIES RISE TO NEAR 7G/KG. FORECAST
SOUNDINGS AND TIME HEIGHTS HINT AT MORE MOISTURE AVAILABLE IN THE
COLUMN HOWEVER. THUS CONFIDENCE IN ANY RAIN REMAINS LOW AND WILL
CONTINUE TO CARRY A LOW CHC POP DURING THIS TIME PERIOD. AS FOR
TEMPS WILL CONTINUE TO HOLD VALUES AT OR BELOW MAVMOS GIVEN THE
ADDITIONAL CLOUD COVER EXPECTED ACROSS THE AREA...ALONG WITH THE
LOW PRECIPITATION CHANCES.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
ISSUED AT 152 AM EDT THU MAY 23 2013
ENSEMBLES IN GOOD AGREEMENT WITH THE LONG WAVE FEATURES DURING THIS
PERIOD. UPPER RIDGE CURRENTLY OVER THE PLAINS IS EXPECTED TO
GRADUALLY SHIFT EAST INTO THE MIDWEST AND OHIO VALLEY BY THE MIDDLE
OF NEXT WEEK. APPEARS THERE IS A POTENTIAL FOR EMBEDDED SHORT WAVE
TROUGHS TO RIDE THROUGH THE RIDGE...AT LEAST ON MONDAY AND TUESDAY.
WILL CONTINUE WITH CHANCE POPS AT THOSE TIMES.
BY NEXT WEDNESDAY AND THURSDAY...ENSEMBLES SUGGEST THE UPPER RIDGE
WILL BUILD MORE AGGRESSIVELY OVER THE AREA AS DEEP TROUGHING DEVELOPS
OVER THE WEST COAST AND ROCKIES. THIS SHOULD HELP TO CAP OFF
PRECIPITATION CHANCES LATER NEXT WEEK...WITH THE ENSEMBLES
SUGGESTING LITTLE THREAT FOR PRECIPITATION AFTER TUESDAY. WILL GO
DRY FOR NEXT WEDNESDAY AND THURSDAY.
&&
.AVIATION /DISCUSSION FOR 240600Z TAF ISSUANCE/...
ISSUED AT 1231 AM EDT FRI MAY 24 2013
POCKETS OF MVFR CEILINGS TO PERSIST AT KBMG AND KIND FOR THE NEXT
FEW HOURS...OTHERWISE VFR CONDITIONS EXPECTED.
STRATOCU DECK CONTINUES TO ERODE FROM THE NORTHWEST...WITH KHUF AND
KLAF NOW MAINLY CLEAR WITH PREDOMINANT CEILING UP TO 3500-4000FT AT
BOTH KBMG AND KIND. RAP DATA INDICATING THAT A N/NE FLOW WILL KEEP
AXIS OF DEEPER MOISTURE THROUGH THE BOUNDARY LAYER ALIGNED ACROSS
THE REGION FOR THE NEXT 3-6 HOURS. CURRENT SATELLITE IMAGERY
SUPPORTS THIS THINKING AS AREA OF LOWER CLOUDS DRIFTING SOUTH ACROSS
NORTHERN INDIANA. WILL KEEP CLOUDS IN AT KBMG AND KIND FOR THE NEXT
FEW HOURS WITH CLEARING THEREAFTER AS DRIER AIR ADVECTS INTO THE
REGION WITH THE HIGH. NORTHERLY WINDS AT 10-15KTS CURRENTLY WILL
DIMINISH TO 5-10KTS LATE.
THE HIGH WILL EXPAND ACROSS THE OHIO VALLEY WITH QUIET WEATHER
TODAY. PRESENCE OF THE DEPARTING LOW LEVEL THERMAL TROUGH INTO THE
AFTERNOON MAY BE JUST ENOUGH TO GENERATE A FEW CU AT KIND.
OTHERWISE...ANTICIPATE CLEAR SKIES AND NORTHERLY WINDS TO NEAR 10KTS
ALL DAY. MAY START TO SEE SOME THIN CIRRUS DRIFT INTO THE REGION
TONIGHT AS IT SPILLS OVER TOP OF THE UPPER RIDGE OVER THE CENTRAL
PLAINS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...PUMA
NEAR TERM...PUMA
SHORT TERM...PUMA
LONG TERM....JAS
AVIATION...RYAN
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
1231 AM EDT FRI MAY 24 2013
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 300 PM EDT THU MAY 23 2013
UPPER TROUGH ACROSS THE LOWER GREAT LAKES WILL MOVE SOUTHEAST ACROSS
THE APPALACHIANS ON FRIDAY AS COOL CANADIAN HIGH PRESSURE SETTLES
ACROSS THE GREAT LAKES AND OHIO VALLEY. THIS WILL RESULT IN CLEARING
TONIGHT WITH BELOW TEMPERATURES THROUGH THE MEMORIAL DAY WEEKEND.
SHOWER CHANCES WILL RETURN BY SATURDAY. TEMPERATURES WILL RETURN TO
NEAR NORMAL MEMORIAL DAY AND ABOVE NORMAL BY MIDWEEK NEXT WEEK.
THUNDERSTORM CHANCES WILL ALSO RETURN NEXT WEEK AS GULF MOISTURE
SPREADS NORTH ACROSS THE OHIO VALLEY.
&&
.NEAR TERM /REST OF TONIGHT/...
ISSUED AT 945 PM EDT THU MAY 23 2013
UPDATE...
HUNG ONTO CLOUD COVER A FEW HOURS LONGER THAN ORIGINAL
FORECAST...BUT ANTICIPATE CLEARING TO ACCELERATE AFTER MIDNIGHT AS
HIGH PRESSURE MAKES PUSH INTO FORECAST AREA. THIS WILL RESULT IN
SUBSTANTIAL RADIATIONAL COOLING AND TEMPS DIPPING INTO THE UPPER
30S/LOW 40S. CURRENTLY...TEMPS ACROSS THE AREA ARE IN THE UPPER
40S/LOW 50S. CURRENT RADAR MOSAIC IS SHOWING A FEW LIGHT RETURNS
OVER THE NORTHEAST QUADRANT AS ORIGINALLY EXPECTED...BUT THESE
SHOULD DISSIPATE WITHIN THE NEXT HOUR.
PREVIOUS DISCUSSION...
MAIN CHALLENGES TONIGHT WILL BE TIMING OF END OF SHOWERS...CLEARING
AND FINALLY TEMPERATURES AS AN UPPER LOW DROPS SOUTHEAST ACROSS THE
LOWER GREAT LAKES AND COOL CANADIAN HIGH SURFACE BUILDS IN BEHIND A
COLD FRONT.
MODELS IN GOOD AGREEMENT ON DROPPING AN UPPER TROUGH...ACROSS THE
WESTERN GREAT LAKES THIS AFTERNOON...TO LAKE ERIE BY FRIDAY MORNING.
IN ADDITION...COOL CANADIAN HIGH PRESSURE WILL BUILD IN BEHIND A
COLD FRONT THAT WAS PRESENTLY NEAR AN IND-HUF LINE. THIS WILL ALLOW
CLEARING FROM NORTHWEST TO SOUTHEAST AS WELL AS AN END TO THE
SHOWERS. THE SHOWERS SHOULD ONLY HANG AROUND TIL DARK ACROSS OUR
EASTERN COUNTIES...SO PULLED SLIGHT CHANCE SHOWER POPS AFTER 02Z.
LEANED TOWARD THE COLDER 12Z NAM MOS WHICH WAS BRINGING OVERNIGHT
LOWS IN THE UPPER 30S ACROSS OUR NORTHWEST OVERNIGHT AND 40S
ELSEWHERE. NORTHWEST WINDS WILL DROP TO BELOW 10 KNOTS AT DARK AS
WELL.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
ISSUED AT 300 PM EDT THU MAY 23 2013
MAIN FOCUS TO THE SHORT TERM WILL BE ON POPS FOR THE MEMORIAL DAY
WEEKEND WITH SO MANY OUTDOOR ACTIVITIES ON TAP.
MODELS IN GOOD AGREEMENT ON COOL CANADIAN HIGH PRESSURE...KEEPING
TEMPERATURES BELOW NORMAL THROUGH THE WEEKEND AS UPPER RIDGE CAMPS
OUT ACROSS THE PLAINS. MODEL TIME SECTIONS SUGGEST CLEAR SKIES
FRIDAY AND FRIDAY NIGHT WITH A DRY COLUMN AND HIGH PRESSURE IN
PLACE. HOWEVER...MODELS IN AGREEMENT ON BRINGING QPF TO ALL OR PARTS
OF CENTRAL INDIANA SATURDAY THROUGH SUNDAY AS UPPER WAVES TOP THE
CENTRAL RIDGE AND DROP SOUTHEAST ACROSS CENTRAL INDIANA. IN
ADDITION...305K ISENTROPIC LIFT WILL BE PLACE WITH INCREASING
MOISTURE. THUS...WILL ADD SMALL POPS SATURDAY AND SATURDAY NIGHT
ACROSS ALL BUT NORTHEASTERN PARTS OF THE FORECAST AREA AND RAISE
POPS SLIGHTLY ON SUNDAY WITH GENERALLY CHANCE POPS WEST OF
INTERSTATES 69 AND 65 AND SLIGHT CHANCE POPS EAST. GULF MOISTURE
DOES NOT START INCREASING UNTIL EARLY NEXT WEEK...AND MODEL TIME
SECTIONS ALSO REVEAL DRY AIR BELOW 850 MILLIBARS. SO...AM
COMFORTABLE WITH THE LOWER ALLBLEND POPS. WOULD NOT RULE OUT THUNDER
SUNDAY...BUT BEST INSTABILITY WILL BE WEST OF CENTRAL INDIANA.
ALLBLEND TEMPERATURES RESEMBLE THE CLOSE MOS AND LOOK REASONABLE
WITH THE COOL CANADIAN AIR POISED TO HANG AROUND.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
ISSUED AT 152 AM EDT THU MAY 23 2013
MODELS ARE SIMILAR ENOUGH FOR THE MOST PART THAT THE ALL BLEND
INITIALIZATION WAS USED FOR MOST ITEMS.
A WARM FRONT WILL REMAIN IN THE NEIGHBORHOOD EARLY IN THE
EXTENDED...WHICH WILL ALLOW SOME SHOWERS AND THUNDERSTORMS TO
DEVELOP. LOCATION OF FRONT AND TIMING OF ITS MOVING NORTHEAST
REMAINS SOMEWHAT UNCERTAIN...SO RELUCTANTLY KEPT LOW POPS IN SUNDAY
NIGHT INTO WEDNESDAY /EVEN THOUGH IT LIKELY WILL NOT RAIN EACH
PERIOD/. RIDGING WILL THEN BUILD IN FOR THE END OF THE PERIOD.
TEMPERATURES WILL WARM THROUGH THE PERIOD AS THE FRONT LIFTS
NORTHEAST AND UPPER RIDGING BUILDS IN.
&&
.AVIATION /DISCUSSION FOR 240600Z TAF ISSUANCE/...
ISSUED AT 1231 AM EDT FRI MAY 24 2013
POCKETS OF MVFR CEILINGS TO PERSIST AT KBMG AND KIND FOR THE NEXT
FEW HOURS...OTHERWISE VFR CONDITIONS EXPECTED.
STRATOCU DECK CONTINUES TO ERODE FROM THE NORTHWEST...WITH KHUF AND
KLAF NOW MAINLY CLEAR WITH PREDOMINANT CEILING UP TO 3500-4000FT AT
BOTH KBMG AND KIND. RAP DATA INDICATING THAT A N/NE FLOW WILL KEEP
AXIS OF DEEPER MOISTURE THROUGH THE BOUNDARY LAYER ALIGNED ACROSS
THE REGION FOR THE NEXT 3-6 HOURS. CURRENT SATELLITE IMAGERY
SUPPORTS THIS THINKING AS AREA OF LOWER CLOUDS DRIFTING SOUTH ACROSS
NORTHERN INDIANA. WILL KEEP CLOUDS IN AT KBMG AND KIND FOR THE NEXT
FEW HOURS WITH CLEARING THEREAFTER AS DRIER AIR ADVECTS INTO THE
REGION WITH THE HIGH. NORTHERLY WINDS AT 10-15KTS CURRENTLY WILL
DIMINISH TO 5-10KTS LATE.
THE HIGH WILL EXPAND ACROSS THE OHIO VALLEY WITH QUIET WEATHER
TODAY. PRESENCE OF THE DEPARTING LOW LEVEL THERMAL TROUGH INTO THE
AFTERNOON MAY BE JUST ENOUGH TO GENERATE A FEW CU AT KIND.
OTHERWISE...ANTICIPATE CLEAR SKIES AND NORTHERLY WINDS TO NEAR 10KTS
ALL DAY. MAY START TO SEE SOME THIN CIRRUS DRIFT INTO THE REGION
TONIGHT AS IT SPILLS OVER TOP OF THE UPPER RIDGE OVER THE CENTRAL
PLAINS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...MK
NEAR TERM...MK/TDUD
SHORT TERM...MK
LONG TERM....50
AVIATION...RYAN
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 GOODLAND KS
1151 AM MDT FRI MAY 24 2013
.UPDATE...
ISSUED AT 819 AM MDT FRI MAY 24 2013
MADE A FEW CHANGES TO THE FORECAST FOR TODAY. THE FIRST BEING
TO INCREASE THE WINDS FOR TODAY...ESPECIALLY DURING THE MORNING.
WINDS HAVE BEEN VARYING QUITE A BIT OVER THE PAST COUPLE OF HOURS.
HAVE BEEN CONTEMPLATING A WIND ADVISORY FOR THE WESTERN 2/3S OF
THE AREA. BIGGEST UNCERTAINTY IS WILL THE SUSTAINED WINDS REMAIN
AT 30 MPH OR CONTINUE TO VARY. IN ADDITION THE WINDS MAY
STRENGTHEN DURING THE AFTERNOON BEHIND THE WARM FRONT. AT THIS
POINT WILL ONLY INCREASE THE SUSTAINED WINDS TO JUST UNDER 30 MPH
FOR THE REST OF THE DAY FOR THE MAJORITY OF THE AREA...WHICH IS
JUST UNDER WIND ADVISORY CRITERIA. IF CRITERIA IS REACHED AM
CONFIDENT IT WILL BE VERY LOW END.
ALSO REMOVED THE MENTION OF FOG FOR ALL BUT EAST CENTRAL COLORADO
THIS MORNING. WEB CAMS AT FIRST VIEW AND GENOA BOTH SHOW
VISIBILITIES OF LESS THAN A MILE. DUE TO THE RATHER SMALL AREA
BEING AFFECTED AND SINCE THE FOG WILL BEGIN TO LIFT IN THE NEXT
HOUR OR SO...WILL NOT BE ISSUING ANY FOG RELATED HAZARDS.
DID DROP THE CHANCES FOR PRECIP. DOWN SOME THIS MORNING OVER THE
EAST. MODELS DO SHOW A MINOR UPPER LEVEL SHORT WAVE TROUGH MOVING
THROUGH...HOWEVER SOUNDINGS DO NOT LOOK VERY FAVORABLE FOR STORM
DEVELOPMENT THIS MORNING. WILL LEAVE A SLIGHT CHANCE IN...BUT THIS
MAY BE TOO MUCH FOR THE MORNING.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)
ISSUED AT 434 AM MDT FRI MAY 24 2013
FORECAST PROBLEMS WILL BE NUMEROUS THROUGH THE WEEKEND. SATELLITE
SHOWING A FASTER/MORE PROGRESSIVE FLOW OVER THE PACIFIC WHICH THEN
TRANSITIONS TO A SLOWER AND MORE AMPLIFIED FLOW OVER NORTH AMERICA.
THE RIDGE OVER THE CENTRAL PORTION OF THE COUNTRY HAS INCREASED IN
AMPLITUDE OVER THE LAST 24 HOURS. UPPER LOW OVER THE PACIFIC
NORTHWEST HAS MOVED LITTLE IN THE LAST 24 HOURS. FRONT THAT MOVED
THROUGH YESTERDAY REMAINS DRAPED WELL SOUTH AND WEST OF THE AREA AT
THIS TIME.
THE SREF...NAM AND CANADIAN INITIALIZED BEST ON THE JET LEVEL WINDS
OVER OUR AREA. MODELS HAVING A LITTLE TROUBLE WITH THE DETAILS AT
MID LEVELS. OVERALL THE SREF AND NAM WERE DOING SLIGHTLY BETTER THAN
THE GFS...CANADIAN AND CANADIAN. THE NAM LOOKED LIKE IT WAS CATCHING
THE MINOR SHORTWAVE TROUGH TO OUR SOUTHWEST THE BEST. THE GFS WAS
DOING SLIGHTLY BETTER THAN THE ECMWF ON THE LOW LEVEL THERMAL FIELD.
THE GFS WAS TOO AGGRESSIVE WITH THE LOW LEVEL MOISTURE RETURN WITH
THE NAM DOING A LITTLE BETTER. MODELS DO NOT QUITE HAVE THE BOUNDARY
TO OUR SOUTH QUITE FAR ENOUGH SOUTH. THE NAM WAS DOING A LITTLE
BETTER HERE. ALSO MODELS HAD QPF TOO FAR NORTH BY 06Z WITH THE GFS...
CANADIAN AND THE SREF THE WORST OFFENDERS. AGAIN THE NAM WAS DOING
BETTER HERE.
TODAY/TONIGHT...MOST OF THE MODEL OUTPUT SHOWS A WEAK LEFT FRONT
QUADRANT OVER THE AREA BEGINNING NEAR 12Z AND MAINLY AFFECTING THE
SOUTHEAST HALF. A SMALL CLUSTER OF THUNDERSTORMS HAD DEVELOPED OVER
NORTHEAST NEW MEXICO AND THE PANHANDLE AREA. THIS LOOKS TO BE IN
RESPONSE TO SHORTWAVE TROUGH AND THE WEAK LEFT FRONT QUADRANT OF THE
JET. HOWEVER THAT DISSIPATED WITH ISOLATED THUNDERSTORMS DEVELOPING
OVER/NEAR THE EASTERN PORTION OF THE AREA.
THE NAM FOR THE MOST PART HAS THIS AREA DEPICTED WELL...ESPECIALLY
FOR THE JET. SO GOING BY THAT...WILL HAVE A SLIGHT CHANCE TO CHANCE
OF THUNDERSTORMS THROUGH MAINLY THE MORNING WITH IT POSSIBLY
LINGERING INTO EARLY AFTERNOON IN THE FAR EAST. STRATUS IS MOSTLY
OCCURRING OVER THE AREA AT THIS TIME WITH THE FOG CONFINED TO EASTERN
COLORADO. THIS MAKES SENSE WITH THIS BEING THE MAIN AREA OF LOW LEVEL
TRANSPORT OF MOISTURE AT THIS TIME. THE HRRR AND NAM INDICATE THE
BEST CHANCE OF FOG OVER THE WESTERN HALF OF THE AREA. A FEW SPOTS
ALSO REPORTING DRIZZLE AND SOUNDINGS WOULD INDICATE THAT WILL
CONTINUE INTO THIS MORNING. SO WILL HAVE AREAS OF FOG WITH PATCHY
DRIZZLE IN THE WESTERN HALF AND PATCHY FOG FURTHER EAST.
SOUTHERLY WINDS INCREASE INTO THE WINDY CATEGORY. GRADIENT DEFINITELY
SUPPORTS NEAR ADVISORY CRITERIA IN THE WEST BUT THERE THE 3 HOUR
PRESSURE FALLS ARE NOT THAT HIGH. GLD VWP DEFINITELY WOULD
SUPPORT WINDY. WILL RAISE WINDS TO NEAR ADVISORY IN THE FAR WEST.
NOW FOR THE PRECIPITATION CHANCES DURING THE AFTERNOON AND NIGHT.
SUBSIDENCE/DRYING OCCURS OUT EAST RATHER QUICKLY AFTER FIRST
SHORTWAVE. INSTABILITY AXIS...BEST HEATING...MID/UPPER LEVEL LIFT
AND SURFACE CONVERGENCE DEVELOPS NEAR OR OVER THE WESTERN PORTION OF
THE AREA. SO WILL GRADUALLY RAMP UP POPS DURING THE AFTERNOON. BEST
LIFT AND MOISTURE LOOK TO RESIDE OVER THE NORTH DURING THE NIGHT
AND HAVE INCREASED POPS OVER THE NORTH WITH LOWER POPS FURTHER
SOUTH. THUNDERSTORMS LOOK TO BE DONE BY 12Z. LOW LEVEL MOISTURE
INCREASES OVER THE EASTERN HALF TO TWO THIRDS AFTER 06Z. AT THIS TIME
MODELS INDICATING MOSTLY STRATUS. WILL INSERT FOG WITH THE GREATEST
CHANCE IN THE FAR EAST.
NOT A GOOD FEEL ON THE MAXES WITH THEM BEING DETERMINED BY THE
EXTENT OF THE STRATUS AND HOW LONG IT TAKES TO BURN OFF. IT IS
POSSIBLE THAT THICK CLOUD COVER WILL NOT BREAK UP UNTIL LATE
MORNING. SO TRENDED THE FORECAST COOLER.
SATURDAY/SATURDAY NIGHT...FOG WILL CLEAR OUT DURING THE MORNING.
MODELS NOT AGREEING WHERE DRY LINE ENDS UP...WHERE THE INSTABILITY
AXIS ENDS UP...WHERE THE CAP IS THE LEAST...AND SHORTWAVE DETAILS.
AT THIS TIME IT LOOKS LIKE THE DRY LINE ENDS UP NEAR OR A LITTLE
WEST OF THE COLORADO BORDER. ONE SHORTWAVE TROUGH EXITS THE EASTERN
PORTION OF THE AREA EARLY IN THE AFTERNOON WITH ANOTHER ONE
APPROACHING LATE IN THE AFTERNOON WITH THE BRUNT OF ITS LIFT COMING
THROUGH DURING THE NIGHT. MODELS ARE GENERATING QPF WHERE THERE IS
A STRONG CAP.
AS IT LOOKS NOW THE MAIN TIME FOR PRECIPITATION WILL WAIT TO BEGIN
UNTIL MID TO LATE EVENING. THE BEST CHANCE FOR THUNDERSTORMS WILL
BE EAST OF THE COLORADO BORDER...AND ESPECIALLY IN THE FAR EAST.
LOW LEVEL THERMAL FIELD IS MUCH WARMER THAN TODAYS. HOWEVER...IF
STRATUS/FOG LAST LONGER OR THE LEE TROUGH IS STRONGER/FURTHER WEST...
THE WINDS WILL BE MORE FROM AN EASTERLY DIRECTION AND NOT ALLOW FOR
AS BIG A WARM UP. KEPT THE WESTERN AREAS WARMER WITH COOLER MAXES
FURTHER EAST.
IN REGARDS TO FIRE...THE LOWEST RHS LOOK TO BE IN COLORADO AT THIS
TIME. HOWEVER...THAT IS WHERE THE LIGHTEST WIND FIELD IS. DUE TO A
LOT OF UNCERTAINTY...WAS NOT CONFIDENT ENOUGH TO THROW OUT A WATCH.
WILL HIGHLIGHT IN THE FIRE WEATHER FORECAST AND HWO.
SUNDAY/SUNDAY NIGHT...A LOT MORE DISAGREEMENT IN DETAILS SHOW UP IN
THIS PERIOD. CURRENT MODEL OUTPUT SUPPORTED THE GOING PRECIPITATION
FORECAST FOR THIS PERIOD AND LEFT IT ALONE. ALSO ONLY MADE SLIGHT
ADJUSTMENTS TO THE TEMPERATURE FORECAST AS WELL. P
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 235 AM MDT FRI MAY 24 2013
MEDIUM RANGE MODEL DIFFERENCES EMERGE EARLY IN THE EXTENDED
PERIOD...PARTICULARLY WITH REGARD TO AMPLITUDE OF UPPER FLOW
PATTERN. THE ECMWF IS MORE AMPLIFIED ON MONDAY WITH BOTH THE UPPER
RIDGE POSITIONED TO OUR EAST AND ALSO THE WESTERN CONUS UPPER
TROUGH. THE POSITION OF THESE FEATURES WILL PLACE OUR AREA IN
SOUTHWESTERLY FLOW ALOFT WITH THE LIKELIHOOD OF WEAK EMBEDDED
DIFFICULT TO TIME SHORTWAVES THAT COULD POTENTIALLY ENHANCE
PRECIPITATION DEVELOPMENT. BY TUESDAY THE PATTERN AMPLIFIES
FURTHER AND ECMWF CLOSES OFF AN UPPER LOW OVER THE SOUTHWEST
CONUS. GFS MAINTAINS AN OPEN WAVE AND SHIFTS IT EASTWARD WITH
NOTICEABLE HEIGHT FALLS OVER OUR AREA BY LATE TUESDAY AND
ESPECIALLY WEDNESDAY. THE NEW 00Z ECMWF HAS TRENDED THE DIRECTION
OF THE MORE PROGRESSIVE GFS AND OPENS UP THE SOUTHWEST CONUS UPPER
LOW RATHER THAN KEEP IT CLOSED AND SLOWLY MOVING IT EAST AS THE
12Z ECMWF INDICATED. STILL THE ECMWF IS CONSIDERABLY SLOWER THAN
THE GFS WITH THE EASTWARD PROGRESSION OF THIS TROUGH. THIS LEADS
TO A LOW CONFIDENCE FORECAST NEXT WEEK. GFS WOULD FAVOR A
POTENTIALLY WIDESPREAD PRECIPITATION / ORGANIZED CONVECTIVE EVENT
WEDNESDAY WHILE THE ECMWF SOLUTION WOULD SUPPORT A SIMILAR
SITUATION BY LATE WEDNESDAY / WEDNESDAY NIGHT INTO THURSDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1142 AM MDT FRI MAY 24 2013
MVFR TO VFR CONDITIONS ARE FORECAST FOR THE 18Z TAFS. VISIBLE
SATELLITE IMAGERY SHOWS LOW CLOUDS DEPARTING THE AREA. EXPECT KMCK
TO BE OUT OF THE LOW CLOUDS SHORTLY AFTER TAF ISSUANCE. AS THE
CLOUDS CLEAR WINDS HAVE NOT STRENGTHENED MUCH AT ALL SO FAR...SO
AM EXPECTING THIS TO CONTINUE. HOWEVER WINDS WILL REMAIN BREEZY
THROUGH THE EVENING BEFORE SLOWING DURING THE OVERNIGHT HOURS.
LATER THIS AFTERNOON/EARLY EVENING THUNDERSTORMS WILL DEVELOP OVER
EASTERN COLORADO AND DEVELOP/PROGRESS EASTWARD. THE BEST CHANCE
FOR STORMS NEAR KGLD WILL BE AROUND 0Z...WITH STORMS DISSIPATING
AFTER A FEW HOURS. STRONG TO SEVERE WIND GUSTS WILL BE POSSIBLE
THROUGH THE EARLY EVENING WITH ANY STORMS THAT DEVELOP. FOR KMCK THE BEST
CHANCE WILL BE AROUND 6Z WITH STORMS MOVING EAST OF THE SITE BY
10Z. THERE MIGHT BE SOME FOG DEVELOPMENT AT KMCK LATE TONIGHT.
HOWEVER CURRENT DATA SUGGESTS ONLY A REDUCTION TO MVFR AT
BEST...SO WILL HOLD OFF PLACING A MENTION OF FOG IN FOR KMCK FOR
THIS TAF ISSUANCE.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JTL
SHORT TERM...BULLER
LONG TERM...BRB
AVIATION...JTL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
829 AM MDT FRI MAY 24 2013
.UPDATE...
ISSUED AT 819 AM MDT FRI MAY 24 2013
MADE A FEW CHANGES TO THE FORECAST FOR TODAY. THE FIRST BEING
TO INCREASE THE WINDS FOR TODAY...ESPECIALLY DURING THE MORNING.
WINDS HAVE BEEN VARYING QUITE A BIT OVER THE PAST COUPLE OF HOURS.
HAVE BEEN CONTEMPLATING A WIND ADVISORY FOR THE WESTERN 2/3S OF
THE AREA. BIGGEST UNCERTAINTY IS WILL THE SUSTAINED WINDS REMAIN
AT 30 MPH OR CONTINUE TO VARY. IN ADDITION THE WINDS MAY
STRENGTHEN DURING THE AFTERNOON BEHIND THE WARM FRONT. AT THIS
POINT WILL ONLY INCREASE THE SUSTAINED WINDS TO JUST UNDER 30 MPH
FOR THE REST OF THE DAY FOR THE MAJORITY OF THE AREA...WHICH IS
JUST UNDER WIND ADVISORY CRITERIA. IF CRITERIA IS REACHED AM
CONFIDENT IT WILL BE VERY LOW END.
ALSO REMOVED THE MENTION OF FOG FOR ALL BUT EAST CENTRAL COLORADO
THIS MORNING. WEB CAMS AT FIRST VIEW AND GENOA BOTH SHOW
VISIBILITIES OF LESS THAN A MILE. DUE TO THE RATHER SMALL AREA
BEING AFFECTED AND SINCE THE FOG WILL BEGIN TO LIFT IN THE NEXT
HOUR OR SO...WILL NOT BE ISSUING ANY FOG RELATED HAZARDS.
DID DROP THE CHANCES FOR PRECIP. DOWN SOME THIS MORNING OVER THE
EAST. MODELS DO SHOW A MINOR UPPER LEVEL SHORT WAVE TROUGH MOVING
THROUGH...HOWEVER SOUNDINGS DO NOT LOOK VERY FAVORABLE FOR STORM
DEVELOPMENT THIS MORNING. WILL LEAVE A SLIGHT CHANCE IN...BUT THIS
MAY BE TOO MUCH FOR THE MORNING.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)
ISSUED AT 434 AM MDT FRI MAY 24 2013
FORECAST PROBLEMS WILL BE NUMEROUS THROUGH THE WEEKEND. SATELLITE
SHOWING A FASTER/MORE PROGRESSIVE FLOW OVER THE PACIFIC WHICH THEN
TRANSITIONS TO A SLOWER AND MORE AMPLIFIED FLOW OVER NORTH AMERICA.
THE RIDGE OVER THE CENTRAL PORTION OF THE COUNTRY HAS INCREASED IN
AMPLITUDE OVER THE LAST 24 HOURS. UPPER LOW OVER THE PACIFIC
NORTHWEST HAS MOVED LITTLE IN THE LAST 24 HOURS. FRONT THAT MOVED
THROUGH YESTERDAY REMAINS DRAPED WELL SOUTH AND WEST OF THE AREA AT
THIS TIME.
THE SREF...NAM AND CANADIAN INITIALIZED BEST ON THE JET LEVEL WINDS
OVER OUR AREA. MODELS HAVING A LITTLE TROUBLE WITH THE DETAILS AT
MID LEVELS. OVERALL THE SREF AND NAM WERE DOING SLIGHTLY BETTER THAN
THE GFS...CANADIAN AND CANADIAN. THE NAM LOOKED LIKE IT WAS CATCHING
THE MINOR SHORTWAVE TROUGH TO OUR SOUTHWEST THE BEST. THE GFS WAS
DOING SLIGHTLY BETTER THAN THE ECMWF ON THE LOW LEVEL THERMAL FIELD.
THE GFS WAS TOO AGGRESSIVE WITH THE LOW LEVEL MOISTURE RETURN WITH
THE NAM DOING A LITTLE BETTER. MODELS DO NOT QUITE HAVE THE BOUNDARY
TO OUR SOUTH QUITE FAR ENOUGH SOUTH. THE NAM WAS DOING A LITTLE
BETTER HERE. ALSO MODELS HAD QPF TOO FAR NORTH BY 06Z WITH THE GFS...
CANADIAN AND THE SREF THE WORST OFFENDERS. AGAIN THE NAM WAS DOING
BETTER HERE.
TODAY/TONIGHT...MOST OF THE MODEL OUTPUT SHOWS A WEAK LEFT FRONT
QUADRANT OVER THE AREA BEGINNING NEAR 12Z AND MAINLY AFFECTING THE
SOUTHEAST HALF. A SMALL CLUSTER OF THUNDERSTORMS HAD DEVELOPED OVER
NORTHEAST NEW MEXICO AND THE PANHANDLE AREA. THIS LOOKS TO BE IN
RESPONSE TO SHORTWAVE TROUGH AND THE WEAK LEFT FRONT QUADRANT OF THE
JET. HOWEVER THAT DISSIPATED WITH ISOLATED THUNDERSTORMS DEVELOPING
OVER/NEAR THE EASTERN PORTION OF THE AREA.
THE NAM FOR THE MOST PART HAS THIS AREA DEPICTED WELL...ESPECIALLY
FOR THE JET. SO GOING BY THAT...WILL HAVE A SLIGHT CHANCE TO CHANCE
OF THUNDERSTORMS THROUGH MAINLY THE MORNING WITH IT POSSIBLY
LINGERING INTO EARLY AFTERNOON IN THE FAR EAST. STRATUS IS MOSTLY
OCCURRING OVER THE AREA AT THIS TIME WITH THE FOG CONFINED TO EASTERN
COLORADO. THIS MAKES SENSE WITH THIS BEING THE MAIN AREA OF LOW LEVEL
TRANSPORT OF MOISTURE AT THIS TIME. THE HRRR AND NAM INDICATE THE
BEST CHANCE OF FOG OVER THE WESTERN HALF OF THE AREA. A FEW SPOTS
ALSO REPORTING DRIZZLE AND SOUNDINGS WOULD INDICATE THAT WILL
CONTINUE INTO THIS MORNING. SO WILL HAVE AREAS OF FOG WITH PATCHY
DRIZZLE IN THE WESTERN HALF AND PATCHY FOG FURTHER EAST.
SOUTHERLY WINDS INCREASE INTO THE WINDY CATEGORY. GRADIENT DEFINITELY
SUPPORTS NEAR ADVISORY CRITERIA IN THE WEST BUT THERE THE 3 HOUR
PRESSURE FALLS ARE NOT THAT HIGH. GLD VWP DEFINITELY WOULD
SUPPORT WINDY. WILL RAISE WINDS TO NEAR ADVISORY IN THE FAR WEST.
NOW FOR THE PRECIPITATION CHANCES DURING THE AFTERNOON AND NIGHT.
SUBSIDENCE/DRYING OCCURS OUT EAST RATHER QUICKLY AFTER FIRST
SHORTWAVE. INSTABILITY AXIS...BEST HEATING...MID/UPPER LEVEL LIFT
AND SURFACE CONVERGENCE DEVELOPS NEAR OR OVER THE WESTERN PORTION OF
THE AREA. SO WILL GRADUALLY RAMP UP POPS DURING THE AFTERNOON. BEST
LIFT AND MOISTURE LOOK TO RESIDE OVER THE NORTH DURING THE NIGHT
AND HAVE INCREASED POPS OVER THE NORTH WITH LOWER POPS FURTHER
SOUTH. THUNDERSTORMS LOOK TO BE DONE BY 12Z. LOW LEVEL MOISTURE
INCREASES OVER THE EASTERN HALF TO TWO THIRDS AFTER 06Z. AT THIS TIME
MODELS INDICATING MOSTLY STRATUS. WILL INSERT FOG WITH THE GREATEST
CHANCE IN THE FAR EAST.
NOT A GOOD FEEL ON THE MAXES WITH THEM BEING DETERMINED BY THE
EXTENT OF THE STRATUS AND HOW LONG IT TAKES TO BURN OFF. IT IS
POSSIBLE THAT THICK CLOUD COVER WILL NOT BREAK UP UNTIL LATE
MORNING. SO TRENDED THE FORECAST COOLER.
SATURDAY/SATURDAY NIGHT...FOG WILL CLEAR OUT DURING THE MORNING.
MODELS NOT AGREEING WHERE DRY LINE ENDS UP...WHERE THE INSTABILITY
AXIS ENDS UP...WHERE THE CAP IS THE LEAST...AND SHORTWAVE DETAILS.
AT THIS TIME IT LOOKS LIKE THE DRY LINE ENDS UP NEAR OR A LITTLE
WEST OF THE COLORADO BORDER. ONE SHORTWAVE TROUGH EXITS THE EASTERN
PORTION OF THE AREA EARLY IN THE AFTERNOON WITH ANOTHER ONE
APPROACHING LATE IN THE AFTERNOON WITH THE BRUNT OF ITS LIFT COMING
THROUGH DURING THE NIGHT. MODELS ARE GENERATING QPF WHERE THERE IS
A STRONG CAP.
AS IT LOOKS NOW THE MAIN TIME FOR PRECIPITATION WILL WAIT TO BEGIN
UNTIL MID TO LATE EVENING. THE BEST CHANCE FOR THUNDERSTORMS WILL
BE EAST OF THE COLORADO BORDER...AND ESPECIALLY IN THE FAR EAST.
LOW LEVEL THERMAL FIELD IS MUCH WARMER THAN TODAYS. HOWEVER...IF
STRATUS/FOG LAST LONGER OR THE LEE TROUGH IS STRONGER/FURTHER WEST...
THE WINDS WILL BE MORE FROM AN EASTERLY DIRECTION AND NOT ALLOW FOR
AS BIG A WARM UP. KEPT THE WESTERN AREAS WARMER WITH COOLER MAXES
FURTHER EAST.
IN REGARDS TO FIRE...THE LOWEST RHS LOOK TO BE IN COLORADO AT THIS
TIME. HOWEVER...THAT IS WHERE THE LIGHTEST WIND FIELD IS. DUE TO A
LOT OF UNCERTAINTY...WAS NOT CONFIDENT ENOUGH TO THROW OUT A WATCH.
WILL HIGHLIGHT IN THE FIRE WEATHER FORECAST AND HWO.
SUNDAY/SUNDAY NIGHT...A LOT MORE DISAGREEMENT IN DETAILS SHOW UP IN
THIS PERIOD. CURRENT MODEL OUTPUT SUPPORTED THE GOING PRECIPITATION
FORECAST FOR THIS PERIOD AND LEFT IT ALONE. ALSO ONLY MADE SLIGHT
ADJUSTMENTS TO THE TEMPERATURE FORECAST AS WELL. P
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 235 AM MDT FRI MAY 24 2013
MEDIUM RANGE MODEL DIFFERENCES EMERGE EARLY IN THE EXTENDED
PERIOD...PARTICULARLY WITH REGARD TO AMPLITUDE OF UPPER FLOW
PATTERN. THE ECMWF IS MORE AMPLIFIED ON MONDAY WITH BOTH THE UPPER
RIDGE POSITIONED TO OUR EAST AND ALSO THE WESTERN CONUS UPPER
TROUGH. THE POSITION OF THESE FEATURES WILL PLACE OUR AREA IN
SOUTHWESTERLY FLOW ALOFT WITH THE LIKELIHOOD OF WEAK EMBEDDED
DIFFICULT TO TIME SHORTWAVES THAT COULD POTENTIALLY ENHANCE
PRECIPITATION DEVELOPMENT. BY TUESDAY THE PATTERN AMPLIFIES
FURTHER AND ECMWF CLOSES OFF AN UPPER LOW OVER THE SOUTHWEST
CONUS. GFS MAINTAINS AN OPEN WAVE AND SHIFTS IT EASTWARD WITH
NOTICEABLE HEIGHT FALLS OVER OUR AREA BY LATE TUESDAY AND
ESPECIALLY WEDNESDAY. THE NEW 00Z ECMWF HAS TRENDED THE DIRECTION
OF THE MORE PROGRESSIVE GFS AND OPENS UP THE SOUTHWEST CONUS UPPER
LOW RATHER THAN KEEP IT CLOSED AND SLOWLY MOVING IT EAST AS THE
12Z ECMWF INDICATED. STILL THE ECMWF IS CONSIDERABLY SLOWER THAN
THE GFS WITH THE EASTWARD PROGRESSION OF THIS TROUGH. THIS LEADS
TO A LOW CONFIDENCE FORECAST NEXT WEEK. GFS WOULD FAVOR A
POTENTIALLY WIDESPREAD PRECIPITATION / ORGANIZED CONVECTIVE EVENT
WEDNESDAY WHILE THE ECMWF SOLUTION WOULD SUPPORT A SIMILAR
SITUATION BY LATE WEDNESDAY / WEDNESDAY NIGHT INTO THURSDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 546 AM MDT FRI MAY 24 2013
IFR CONDITIONS CURRENTLY AT GLD DUE TO LOW CIGS. THIS SHOULD
PERSIST IN THE NEAR TERM FOLLOWED BY AN INCREASE TO MVFR AFTER
AROUND 15-16Z AND EVENTUALLY VFR THIS AFTERNOON. MEANWHILE MVFR
CONDITIONS MAY PERSIST A LITTLE LONGER AT MCK. SOME UNCERTAINTY
WITH REGARD TO CONVECTION LATER THIS EVENING AND TONIGHT SO OPTED
TO LEAVE VCTS OUT FOR NOW. THIS MAY NEED TO BE ADDED AT A LATER TIME IF
CONFIDENCE INCREASES. LATER TONIGHT VFR CONDITIONS DUE TO CIGS ARE
EXPECTED AT MCK.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
UPDATE...JTL
SHORT TERM...BULLER
LONG TERM...BRB
AVIATION...BRB
AREA FORECAST DISCUSSION
NWS GOODLAND KS
550 AM MDT FRI MAY 24 2013
.SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)
ISSUED AT 434 AM MDT FRI MAY 24 2013
FORECAST PROBLEMS WILL BE NUMEROUS THROUGH THE WEEKEND. SATELLITE
SHOWING A FASTER/MORE PROGRESSIVE FLOW OVER THE PACIFIC WHICH THEN
TRANSITIONS TO A SLOWER AND MORE AMPLIFIED FLOW OVER NORTH AMERICA.
THE RIDGE OVER THE CENTRAL PORTION OF THE COUNTRY HAS INCREASED IN
AMPLITUDE OVER THE LAST 24 HOURS. UPPER LOW OVER THE PACIFIC
NORTHWEST HAS MOVED LITTLE IN THE LAST 24 HOURS. FRONT THAT MOVED
THROUGH YESTERDAY REMAINS DRAPED WELL SOUTH AND WEST OF THE AREA AT
THIS TIME.
THE SREF...NAM AND CANADIAN INITIALIZED BEST ON THE JET LEVEL WINDS
OVER OUR AREA. MODELS HAVING A LITTLE TROUBLE WITH THE DETAILS AT
MID LEVELS. OVERALL THE SREF AND NAM WERE DOING SLIGHTLY BETTER THAN
THE GFS...CANADIAN AND CANADIAN. THE NAM LOOKED LIKE IT WAS CATCHING
THE MINOR SHORTWAVE TROUGH TO OUR SOUTHWEST THE BEST. THE GFS WAS
DOING SLIGHTLY BETTER THAN THE ECMWF ON THE LOW LEVEL THERMAL FIELD.
THE GFS WAS TOO AGGRESSIVE WITH THE LOW LEVEL MOISTURE RETURN WITH
THE NAM DOING A LITTLE BETTER. MODELS DO NOT QUITE HAVE THE BOUNDARY
TO OUR SOUTH QUITE FAR ENOUGH SOUTH. THE NAM WAS DOING A LITTLE
BETTER HERE. ALSO MODELS HAD QPF TOO FAR NORTH BY 06Z WITH THE GFS...
CANADIAN AND THE SREF THE WORST OFFENDERS. AGAIN THE NAM WAS DOING
BETTER HERE.
TODAY/TONIGHT...MOST OF THE MODEL OUTPUT SHOWS A WEAK LEFT FRONT
QUADRANT OVER THE AREA BEGINNING NEAR 12Z AND MAINLY AFFECTING THE
SOUTHEAST HALF. A SMALL CLUSTER OF THUNDERSTORMS HAD DEVELOPED OVER
NORTHEAST NEW MEXICO AND THE PANHANDLE AREA. THIS LOOKS TO BE IN
RESPONSE TO SHORTWAVE TROUGH AND THE WEAK LEFT FRONT QUADRANT OF THE
JET. HOWEVER THAT DISSIPATED WITH ISOLATED THUNDERSTORMS DEVELOPING
OVER/NEAR THE EASTERN PORTION OF THE AREA.
THE NAM FOR THE MOST PART HAS THIS AREA DEPICTED WELL...ESPECIALLY
FOR THE JET. SO GOING BY THAT...WILL HAVE A SLIGHT CHANCE TO CHANCE
OF THUNDERSTORMS THROUGH MAINLY THE MORNING WITH IT POSSIBLY
LINGERING INTO EARLY AFTERNOON IN THE FAR EAST. STRATUS IS MOSTLY
OCCURRING OVER THE AREA AT THIS TIME WITH THE FOG CONFINED TO EASTERN
COLORADO. THIS MAKES SENSE WITH THIS BEING THE MAIN AREA OF LOW LEVEL
TRANSPORT OF MOISTURE AT THIS TIME. THE HRRR AND NAM INDICATE THE
BEST CHANCE OF FOG OVER THE WESTERN HALF OF THE AREA. A FEW SPOTS
ALSO REPORTING DRIZZLE AND SOUNDINGS WOULD INDICATE THAT WILL
CONTINUE INTO THIS MORNING. SO WILL HAVE AREAS OF FOG WITH PATCHY
DRIZZLE IN THE WESTERN HALF AND PATCHY FOG FURTHER EAST.
SOUTHERLY WINDS INCREASE INTO THE WINDY CATEGORY. GRADIENT DEFINITELY
SUPPORTS NEAR ADVISORY CRITERIA IN THE WEST BUT THERE THE 3 HOUR
PRESSURE FALLS ARE NOT THAT HIGH. GLD VWP DEFINITELY WOULD
SUPPORT WINDY. WILL RAISE WINDS TO NEAR ADVISORY IN THE FAR WEST.
NOW FOR THE PRECIPITATION CHANCES DURING THE AFTERNOON AND NIGHT.
SUBSIDENCE/DRYING OCCURS OUT EAST RATHER QUICKLY AFTER FIRST
SHORTWAVE. INSTABILITY AXIS...BEST HEATING...MID/UPPER LEVEL LIFT
AND SURFACE CONVERGENCE DEVELOPS NEAR OR OVER THE WESTERN PORTION OF
THE AREA. SO WILL GRADUALLY RAMP UP POPS DURING THE AFTERNOON. BEST
LIFT AND MOISTURE LOOK TO RESIDE OVER THE NORTH DURING THE NIGHT
AND HAVE INCREASED POPS OVER THE NORTH WITH LOWER POPS FURTHER
SOUTH. THUNDERSTORMS LOOK TO BE DONE BY 12Z. LOW LEVEL MOISTURE
INCREASES OVER THE EASTERN HALF TO TWO THIRDS AFTER 06Z. AT THIS TIME
MODELS INDICATING MOSTLY STRATUS. WILL INSERT FOG WITH THE GREATEST
CHANCE IN THE FAR EAST.
NOT A GOOD FEEL ON THE MAXES WITH THEM BEING DETERMINED BY THE
EXTENT OF THE STRATUS AND HOW LONG IT TAKES TO BURN OFF. IT IS
POSSIBLE THAT THICK CLOUD COVER WILL NOT BREAK UP UNTIL LATE
MORNING. SO TRENDED THE FORECAST COOLER.
SATURDAY/SATURDAY NIGHT...FOG WILL CLEAR OUT DURING THE MORNING.
MODELS NOT AGREEING WHERE DRYLINE ENDS UP...WHERE THE INSTABILITY
AXIS ENDS UP...WHERE THE CAP IS THE LEAST...AND SHORTWAVE DETAILS.
AT THIS TIME IT LOOKS LIKE THE DRY LINE ENDS UP NEAR OR A LITTLE
WEST OF THE COLORADO BORDER. ONE SHORTWAVE TROUGH EXITS THE EASTERN
PORTION OF THE AREA EARLY IN THE AFTERNOON WITH ANOTHER ONE
APPROACHING LATE IN THE AFTERNOON WITH THE BRUNT OF ITS LIFT COMING
THROUGH DURING THE NIGHT. MODELS ARE GENERATING QPF WHERE THERE IS
A STRONG CAP.
AS IT LOOKS NOW THE MAIN TIME FOR PRECIPITATION WILL WAIT TO BEGIN
UNTIL MID TO LATE EVENING. THE BEST CHANCE FOR THUNDERSTORMS WILL
BE EAST OF THE COLORADO BORDER...AND ESPECIALLY IN THE FAR EAST.
LOW LEVEL THERMAL FIELD IS MUCH WARMER THAN TODAYS. HOWEVER...IF
STRATUS/FOG LAST LONGER OR THE LEE TROUGH IS STRONGER/FURTHER WEST...
THE WINDS WILL BE MORE FROM AN EASTERLY DIRECTION AND NOT ALLOW FOR
AS BIG A WARMUP. KEPT THE WESTERN AREAS WARMER WITH COOLER MAXES
FURTHER EAST.
IN REGARDS TO FIRE...THE LOWEST RHS LOOK TO BE IN COLORADO AT THIS
TIME. HOWEVER...THAT IS WHERE THE LIGHTEST WIND FIELD IS. DUE TO A
LOT OF UNCERTAINTY...WAS NOT CONFIDENT ENOUGH TO THROW OUT A WATCH.
WILL HIGHLIGHT IN THE FIRE WEATHER FORECAST AND HWO.
SUNDAY/SUNDAY NIGHT...A LOT MORE DISAGREEMENT IN DETAILS SHOW UP IN
THIS PERIOD. CURRENT MODEL OUTPUT SUPPORTED THE GOING PRECIPITATION
FORECAST FOR THIS PERIOD AND LEFT IT ALONE. ALSO ONLY MADE SLIGHT
ADJUSTMENTS TO THE TEMPERATURE FORECAST AS WELL. P
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 235 AM MDT FRI MAY 24 2013
MEDIUM RANGE MODEL DIFFERENCES EMERGE EARLY IN THE EXTENDED
PERIOD...PARTICULARLY WITH REGARD TO AMPLITUDE OF UPPER FLOW
PATTERN. THE ECMWF IS MORE AMPLIFIED ON MONDAY WITH BOTH THE UPPER
RIDGE POSITIONED TO OUR EAST AND ALSO THE WESTERN CONUS UPPER
TROUGH. THE POSITION OF THESE FEATURES WILL PLACE OUR AREA IN
SOUTHWESTERLY FLOW ALOFT WITH THE LIKELIHOOD OF WEAK EMBEDDED
DIFFICULT TO TIME SHORTWAVES THAT COULD POTENTIALLY ENHANCE
PRECIPITATION DEVELOPMENT. BY TUESDAY THE PATTERN AMPLIFIES
FURTHER AND ECMWF CLOSES OFF AN UPPER LOW OVER THE SOUTHWEST
CONUS. GFS MAINTAINS AN OPEN WAVE AND SHIFTS IT EASTWARD WITH
NOTICEABLE HEIGHT FALLS OVER OUR AREA BY LATE TUESDAY AND
ESPECIALLY WEDNESDAY. THE NEW 00Z ECMWF HAS TRENDED THE DIRECTION
OF THE MORE PROGRESSIVE GFS AND OPENS UP THE SOUTHWEST CONUS UPPER
LOW RATHER THAN KEEP IT CLOSED AND SLOWLY MOVING IT EAST AS THE
12Z ECMWF INDICATED. STILL THE ECMWF IS CONSIDERABLY SLOWER THAN
THE GFS WITH THE EASTWARD PROGRESSION OF THIS TROUGH. THIS LEADS
TO A LOW CONFIDENCE FORECAST NEXT WEEK. GFS WOULD FAVOR A
POTENTIALLY WIDESPREAD PRECIPITATION / ORGANIZED CONVECTIVE EVENT
WEDNESDAY WHILE THE ECMWF SOLUTION WOULD SUPPORT A SIMILAR
SITUATION BY LATE WEDNESDAY / WEDNESDAY NIGHT INTO THURSDAY.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING)
ISSUED AT 546 AM MDT FRI MAY 24 2013
IFR CONDITIONS CURRENTLY AT GLD DUE TO LOW CIGS. THIS SHOULD
PERSIST IN THE NEAR TERM FOLLOWED BY AN INCREASE TO MVFR AFTER
AROUND 15-16Z AND EVENTUALLY VFR THIS AFTERNOON. MEANWHILE MVFR
CONDITIONS MAY PERSIST A LITTLE LONGER AT MCK. SOME UNCERTAINTY
WITH REGARD TO CONVECTION LATER THIS EVENING AND TONIGHT SO OPTED
TO LEAVE VCTS OUT FOR NOW. THIS MAY NEED TO BE ADDED AT A LATER TIME IF
CONFIDENCE INCREASES. LATER TONIGHT VFR CONDITIONS DUE TO CIGS ARE
EXPECTED AT MCK.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...BRB
AVIATION...BRB
AREA FORECAST DISCUSSION
NWS GOODLAND KS
434 AM MDT FRI MAY 24 2013
.SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)
ISSUED AT 434 AM MDT FRI MAY 24 2013
FORECAST PROBLEMS WILL BE NUMEROUS THROUGH THE WEEKEND. SATELLITE
SHOWING A FASTER/MORE PROGRESSIVE FLOW OVER THE PACIFIC WHICH THEN
TRANSITIONS TO A SLOWER AND MORE AMPLIFIED FLOW OVER NORTH AMERICA.
THE RIDGE OVER THE CENTRAL PORTION OF THE COUNTRY HAS INCREASED IN
AMPLITUDE OVER THE LAST 24 HOURS. UPPER LOW OVER THE PACIFIC
NORTHWEST HAS MOVED LITTLE IN THE LAST 24 HOURS. FRONT THAT MOVED
THROUGH YESTERDAY REMAINS DRAPED WELL SOUTH AND WEST OF THE AREA AT
THIS TIME.
THE SREF...NAM AND CANADIAN INITIALIZED BEST ON THE JET LEVEL WINDS
OVER OUR AREA. MODELS HAVING A LITTLE TROUBLE WITH THE DETAILS AT
MID LEVELS. OVERALL THE SREF AND NAM WERE DOING SLIGHTLY BETTER THAN
THE GFS...CANADIAN AND CANADIAN. THE NAM LOOKED LIKE IT WAS CATCHING
THE MINOR SHORTWAVE TROUGH TO OUR SOUTHWEST THE BEST. THE GFS WAS
DOING SLIGHTLY BETTER THAN THE ECMWF ON THE LOW LEVEL THERMAL FIELD.
THE GFS WAS TOO AGGRESSIVE WITH THE LOW LEVEL MOISTURE RETURN WITH
THE NAM DOING A LITTLE BETTER. MODELS DO NOT QUITE HAVE THE BOUNDARY
TO OUR SOUTH QUITE FAR ENOUGH SOUTH. THE NAM WAS DOING A LITTLE
BETTER HERE. ALSO MODELS HAD QPF TOO FAR NORTH BY 06Z WITH THE GFS...
CANADIAN AND THE SREF THE WORST OFFENDERS. AGAIN THE NAM WAS DOING
BETTER HERE.
TODAY/TONIGHT...MOST OF THE MODEL OUTPUT SHOWS A WEAK LEFT FRONT
QUADRANT OVER THE AREA BEGINNING NEAR 12Z AND MAINLY AFFECTING THE
SOUTHEAST HALF. A SMALL CLUSTER OF THUNDERSTORMS HAD DEVELOPED OVER
NORTHEAST NEW MEXICO AND THE PANHANDLE AREA. THIS LOOKS TO BE IN
RESPONSE TO SHORTWAVE TROUGH AND THE WEAK LEFT FRONT QUADRANT OF THE
JET. HOWEVER THAT DISSIPATED WITH ISOLATED THUNDERSTORMS DEVELOPING
OVER/NEAR THE EASTERN PORTION OF THE AREA.
THE NAM FOR THE MOST PART HAS THIS AREA DEPICTED WELL...ESPECIALLY
FOR THE JET. SO GOING BY THAT...WILL HAVE A SLIGHT CHANCE TO CHANCE
OF THUNDERSTORMS THROUGH MAINLY THE MORNING WITH IT POSSIBLY
LINGERING INTO EARLY AFTERNOON IN THE FAR EAST. STRATUS IS MOSTLY
OCCURRING OVER THE AREA AT THIS TIME WITH THE FOG CONFINED TO EASTERN
COLORADO. THIS MAKES SENSE WITH THIS BEING THE MAIN AREA OF LOW LEVEL
TRANSPORT OF MOISTURE AT THIS TIME. THE HRRR AND NAM INDICATE THE
BEST CHANCE OF FOG OVER THE WESTERN HALF OF THE AREA. A FEW SPOTS
ALSO REPORTING DRIZZLE AND SOUNDINGS WOULD INDICATE THAT WILL
CONTINUE INTO THIS MORNING. SO WILL HAVE AREAS OF FOG WITH PATCHY
DRIZZLE IN THE WESTERN HALF AND PATCHY FOG FURTHER EAST.
SOUTHERLY WINDS INCREASE INTO THE WINDY CATEGORY. GRADIENT DEFINITELY
SUPPORTS NEAR ADVISORY CRITERIA IN THE WEST BUT THERE THE 3 HOUR
PRESSURE FALLS ARE NOT THAT HIGH. GLD VWP DEFINITELY WOULD
SUPPORT WINDY. WILL RAISE WINDS TO NEAR ADVISORY IN THE FAR WEST.
NOW FOR THE PRECIPITATION CHANCES DURING THE AFTERNOON AND NIGHT.
SUBSIDENCE/DRYING OCCURS OUT EAST RATHER QUICKLY AFTER FIRST
SHORTWAVE. INSTABILITY AXIS...BEST HEATING...MID/UPPER LEVEL LIFT
AND SURFACE CONVERGENCE DEVELOPS NEAR OR OVER THE WESTERN PORTION OF
THE AREA. SO WILL GRADUALLY RAMP UP POPS DURING THE AFTERNOON. BEST
LIFT AND MOISTURE LOOK TO RESIDE OVER THE NORTH DURING THE NIGHT
AND HAVE INCREASED POPS OVER THE NORTH WITH LOWER POPS FURTHER
SOUTH. THUNDERSTORMS LOOK TO BE DONE BY 12Z. LOW LEVEL MOISTURE
INCREASES OVER THE EASTERN HALF TO TWO THIRDS AFTER 06Z. AT THIS TIME
MODELS INDICATING MOSTLY STRATUS. WILL INSERT FOG WITH THE GREATEST
CHANCE IN THE FAR EAST.
NOT A GOOD FEEL ON THE MAXES WITH THEM BEING DETERMINED BY THE
EXTENT OF THE STRATUS AND HOW LONG IT TAKES TO BURN OFF. IT IS
POSSIBLE THAT THICK CLOUD COVER WILL NOT BREAK UP UNTIL LATE
MORNING. SO TRENDED THE FORECAST COOLER.
SATURDAY/SATURDAY NIGHT...FOG WILL CLEAR OUT DURING THE MORNING.
MODELS NOT AGREEING WHERE DRYLINE ENDS UP...WHERE THE INSTABILITY
AXIS ENDS UP...WHERE THE CAP IS THE LEAST...AND SHORTWAVE DETAILS.
AT THIS TIME IT LOOKS LIKE THE DRY LINE ENDS UP NEAR OR A LITTLE
WEST OF THE COLORADO BORDER. ONE SHORTWAVE TROUGH EXITS THE EASTERN
PORTION OF THE AREA EARLY IN THE AFTERNOON WITH ANOTHER ONE
APPROACHING LATE IN THE AFTERNOON WITH THE BRUNT OF ITS LIFT COMING
THROUGH DURING THE NIGHT. MODELS ARE GENERATING QPF WHERE THERE IS
A STRONG CAP.
AS IT LOOKS NOW THE MAIN TIME FOR PRECIPITATION WILL WAIT TO BEGIN
UNTIL MID TO LATE EVENING. THE BEST CHANCE FOR THUNDERSTORMS WILL
BE EAST OF THE COLORADO BORDER...AND ESPECIALLY IN THE FAR EAST.
LOW LEVEL THERMAL FIELD IS MUCH WARMER THAN TODAYS. HOWEVER...IF
STRATUS/FOG LAST LONGER OR THE LEE TROUGH IS STRONGER/FURTHER WEST...
THE WINDS WILL BE MORE FROM AN EASTERLY DIRECTION AND NOT ALLOW FOR
AS BIG A WARMUP. KEPT THE WESTERN AREAS WARMER WITH COOLER MAXES
FURTHER EAST.
IN REGARDS TO FIRE...THE LOWEST RHS LOOK TO BE IN COLORADO AT THIS
TIME. HOWEVER...THAT IS WHERE THE LIGHTEST WIND FIELD IS. DUE TO A
LOT OF UNCERTAINTY...WAS NOT CONFIDENT ENOUGH TO THROW OUT A WATCH.
WILL HIGHLIGHT IN THE FIRE WEATHER FORECAST AND HWO.
SUNDAY/SUNDAY NIGHT...A LOT MORE DISAGREEMENT IN DETAILS SHOW UP IN
THIS PERIOD. CURRENT MODEL OUTPUT SUPPORTED THE GOING PRECIPITATION
FORECAST FOR THIS PERIOD AND LEFT IT ALONE. ALSO ONLY MADE SLIGHT
ADJUSTMENTS TO THE TEMPERATURE FORECAST AS WELL. P
.LONG TERM...(MONDAY THROUGH THURSDAY)
ISSUED AT 235 AM MDT FRI MAY 24 2013
MEDIUM RANGE MODEL DIFFERENCES EMERGE EARLY IN THE EXTENDED
PERIOD...PARTICULARLY WITH REGARD TO AMPLITUDE OF UPPER FLOW
PATTERN. THE ECMWF IS MORE AMPLIFIED ON MONDAY WITH BOTH THE UPPER
RIDGE POSITIONED TO OUR EAST AND ALSO THE WESTERN CONUS UPPER
TROUGH. THE POSITION OF THESE FEATURES WILL PLACE OUR AREA IN
SOUTHWESTERLY FLOW ALOFT WITH THE LIKELIHOOD OF WEAK EMBEDDED
DIFFICULT TO TIME SHORTWAVES THAT COULD POTENTIALLY ENHANCE
PRECIPITATION DEVELOPMENT. BY TUESDAY THE PATTERN AMPLIFIES
FURTHER AND ECMWF CLOSES OFF AN UPPER LOW OVER THE SOUTHWEST
CONUS. GFS MAINTAINS AN OPEN WAVE AND SHIFTS IT EASTWARD WITH
NOTICEABLE HEIGHT FALLS OVER OUR AREA BY LATE TUESDAY AND
ESPECIALLY WEDNESDAY. THE NEW 00Z ECMWF HAS TRENDED THE DIRECTION
OF THE MORE PROGRESSIVE GFS AND OPENS UP THE SOUTHWEST CONUS UPPER
LOW RATHER THAN KEEP IT CLOSED AND SLOWLY MOVING IT EAST AS THE
12Z ECMWF INDICATED. STILL THE ECMWF IS CONSIDERABLY SLOWER THAN
THE GFS WITH THE EASTWARD PROGRESSION OF THIS TROUGH. THIS LEADS
TO A LOW CONFIDENCE FORECAST NEXT WEEK. GFS WOULD FAVOR A
POTENTIALLY WIDESPREAD PRECIPITATION / ORGANIZED CONVECTIVE EVENT
WEDNESDAY WHILE THE ECMWF SOLUTION WOULD SUPPORT A SIMILAR
SITUATION BY LATE WEDNESDAY / WEDNESDAY NIGHT INTO THURSDAY.
&&
.AVIATION....(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1118 PM MDT THU MAY 23 2013
STRATUS CONTINUES TO STREAM NORTH ACROSS THE AREA AND CIGS WILL BE
LOWERING AT BOTH KGLD AND KMCK THROUGH THE OVERNIGHT HOURS. IN
ADDITION...SOUTHEASTERLY SURFACE WINDS WILL GRADUALLY INCREASE...
WHICH WILL FAVOR STRATUS OVER FOG SO WILL NOT INCLUDE ANY VISIBILITY
RESTRICTIONS. ON FRIDAY...CIGS WILL BE SLOW TO LIFT WITH PERSISTENT
MOIST SOUTHEASTERLY FLOW. THUNDERSTORMS WILL BE POSSIBLE BY THE
AFTERNOON OR EARLY EVENING AT EITHER LOCATION.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM...BRB
AVIATION...024
AREA FORECAST DISCUSSION
NWS TOPEKA KS
347 AM CDT FRI MAY 24 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 347 AM CDT FRI MAY 24 2013
00Z 500MB RAOBS INDICATE RISING HEIGHTS OVER THE CENTRAL CONUS WITH
UPPER TROFS FLANKING A DEVELOPING RIDGE. THE RIDGE AT 700MB WAS OVER
EASTERN KANSAS...WHILE AT 850MB DEWPOINTS RANGED FROM AROUND 3C AT
KTOP AND KOUN TO AROUND 12 AT KDDC...KAMA...AND KFWD. WESTERN KANSAS
RADARS AND OBSERVATIONS INDICATING SOME ISOLATED MID LEVEL
CONVECTION WITH A WEAKENING CONVECTIVE CLUSTER OVER EASTERN COLORADO.
ISENTROPIC LIFT INCREASES AND LOWERS TO AROUND 850MB TODAY AS THE
700MB RIDGE SHIFTS TO THE MISSOURI BORDER. LOW/MID LEVELS SLOWLY
SATURATE...AND THERE MAY BE ENOUGH LIFT FOR ISOLATED TO SCATTERED
ELEVATED STORMS BY SUNRISE AND CONTINUING THROUGH MUCH OF THE DAY.
CHANCES SHOULD BE LIMITED TO THE WESTERN PORTIONS OF THE COUNTY
WARNING AREA WITH THE MID LEVEL RIDGE STILL IN PLACE. SOME WEAKENING
IN THE WAA OCCURS IN THE AFTERNOON AND COULD LEAD TO A DOWNWARD
TREND...BUT A STRONGER LOW LEVEL JET IN AN INCREASINGLY MOIST
TROPOSPHERE SUGGESTS SOME CHANCE FOR CONVECTION INCREASING AND
SPREADING ACROSS KANSAS TONIGHT. THERE IS NOT MUCH OF A FOCUSING
MECHANISM TO POINT TO ANY PARTICULAR LOCATIONS IN THE REGION FOR
BETTER PRECIP CHANCES...BUT KEPT LARGEST CHANCES IN THE NORTH AND
WEST WHERE SLIGHTLY BETTER MOISTURE ADVECTION AND PRECIPITABLE WATER
SHOULD RESIDE. SOUTHEAST WINDS WILL INCREASE MORE THAN RECENT DAYS
BY LATE THIS MORNING AS LEE LOW PRESSURE DEEPENS...WITH THE BETTER
MIXING AND MODEST LOW LEVEL WAA RESULTING IN SLIGHTLY WARMER HIGHS.
LOWS TONIGHT WILL BE SEVERAL DEGREES WARMER IN THE MORE MOIST AND
INSULATED AIRMASS.
.LONG TERM...(SATURDAY THROUGH THURSDAY)
ISSUED AT 347 AM CDT FRI MAY 24 2013
THE WEEKEND PATTERN WILL BE CHARACTERIZED BY TROUGHS IN THE WEST AND
EAST WITH A RIDGE OVER THE CENTRAL PLAINS THIS PATTERN REMAINS INTO
MONDAY BEFORE THE RIDGE MOVES OFF TO THE EAST BY WEDNESDAY. SEVERAL
PIECES OF ENERGY WILL MOVE OUT OF THE WESTERN TROUGH FROM SATURDAY
THROUGH NEXT WEDNESDAY....HOWEVER THE UPPER TROUGH WILL MOVE OUT
INTO THE EASTERN ROCKIES BY FRIDAY. THIS WILL PROVIDE NUMEROUS
CHANCES FOR THUNDERSTORMS THROUGH THE PERIOD. THE TIMING OF THE
WAVES EMANATING OUT OF THE WESTERN TROUGH IS HARD TO CALL AT THIS
TIME. ALSO ANY MESOSCALE BOUNDARIES LEFT OVER FROM DECAYING
OVERNIGHT CONVECTION WILL PROVIDE A FOCUS FOR LATER DEVELOPMENT.
MOISTURE WILL MOVE BACK INTO CENTRAL AND EASTERN KANSAS AS THE LOW
LEVEL JET BECOMES SOUTH TO SOUTHWEST OVER CENTRAL AND EASTERN
KANSAS. A THETA-E RIDGE WILL STRETCH ACROSS NORTH CENTRAL AND
NORTHEAST KANSAS THROUGH MUCH OF THE NEXT WEEK. CONVECTION IS
EXPECTED TO DEVELOP IN THE WESTERN HIGH PLAINS AND INTO CENTRAL AND
EASTERN NEBRASKA SATURDAY NIGHT WITH ISENTROPIC LIFT OVER A FRONTAL
BOUNDARY NEAR THE NEBRASKA BORDER. HIGHEST CHANCES WILL REMAIN
FOCUSED NORTH. AGAIN ANY OLD OUTFLOW BOUNDARY ACROSS THE CWA COULD
BE A FOCUS FOR AFTERNOON CONVECTION AS MCS/S MOVE ACROSS NEBRASKA
AND NORTHERN KANSAS ON SUNDAY. INSTABILITY COULD BE AS HIGH AS 3000
J/KG TO 4800 J/KG MUCAPE ACROSS THE CWA. DEEP LAYER SHEAR AROUND 30
KTS SUNDAY AFTERNOON. MOISTURE TRANSPORT VECTORS INCREASE ACROSS
CENTRAL KANSAS INTO SOUTHEAST NEBRASKA THROUGH THE DAY. PRECIPITABLE
WATER VALUES INCREASE TO AROUND 1.5 INCHES. LOCALLY HEAVY RAINFALL
IS POSSIBLE WITH ANY CONVECTION SUNDAY AND SUNDAY NIGHT.
CONTINUED CHANCES FOR NOCTURNAL CONVECTION WILL CONTINUE THROUGH THE
BULK OF THE WEEK WITH MORE WIDELY SCATTERED ACTIVITY IN THE
AFTERNOON AND EVENING HOURS. IF THUNDERSTORMS CONTINUE TO MOVE OVER
THE SAME AREAS DURING THE WEEK COULD SEE SOME FLOOD/FLASH FLOODING.
HIGHS WILL BE IN THE 80S THROUGH THE MONDAY THROUGH THURSDAY PERIOD
WITH LOWS IN THE 60S.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1145 PM CDT THU MAY 23 2013
MODELS CONTINUE TO SHOW INCREASING MOISTURE ADVECTION UP THROUGH
CENTRAL KS AS THE LOW LEVEL JET VEERS AROUND MORE TO THE SOUTH.
LATEST SATELLITE SHOWS A BAND OF AC WITHIN THE AXIS OF MOISTURE
ADVECTION. THEREFORE WILL CONTINUE WITH A MENTION OF VCSH AT MHK
BY MID MORNING AS ISENTROPIC PROGS SHOW SOME LIFT WITH LOWERING
COND PRES DEF DEVELOPING ACROSS NORTH CENTRAL KS. THINK TOP AND FOE
WILL REMAIN MAINLY TO THE EAST OF THE BETTER MOISTURE ADVECTION.
THE NAM HAS BACKED OFF ON THE LOW LEVEL SATURATION AND MVFR CIGS.
WITH THE RUC SHOWING SOME CONSISTENCY IN KEEPING CIGS VFR...HAVE
TAKEN OUT THE MENTION OF MVFR CIGS AT MHK.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...65
LONG TERM...53
AVIATION...WOLTERS
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1145 PM CDT THU MAY 23 2013
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 341 PM CDT THU MAY 23 2013
ALTHOUGH THE SURFACE LOW THAT IMPACTED THE REGION THIS PAST WEEKEND
HAS PROGRESSED EAST OF THE GREAT LAKES REGION...AN ASSOCIATED COLD
FRONT STILL STRETCHED WESTWARD ACROSS NORTHERN MISSOURI AND INTO
EASTERN NEBRASKA. ENOUGH MOISTURE AND LIFT WAS PRESENT NEAR THIS
BOUNDARY TO KEEP MUCH OF NORTHEASTERN KANSAS UNDER CLOUD COVER
THROUGH MUCH OF THE DAY TODAY. VISIBLE SATELLITE IMAGERY SHOWED
SOME SCATTERING OUT WITH THE CLOUD COVER BY MID AFTERNOON...WHICH
ALLOWED AFTERNOON TEMPERATURES TO REACH INTO THE UPPER 60S TO LOWER
70S.
SURFACE HIGH PRESSURE OVER THE NORTHERN PLAINS HAS SPILLED SOUTHWARD
INTO THE CENTRAL PLAINS TODAY AND WILL SHIFT EAST OF THE AREA
TONIGHT INTO FRIDAY AS THE UPPER LEVEL RIDGE CONTINUES TO BUILD OVER
THE CENTRAL AND SOUTHERN PLAINS. EXPECT ANOTHER COOLER NIGHT ACROSS
THE CWA THIS EVENING AS OVERNIGHT LOWS LOOK TO DROP INTO THE
UPPER 40S TO LOWER 50S. MODELS CONTINUE TO SHOW SEVERAL EMBEDDED
SHORTWAVES DEVELOPING ALONG THE NORTHERN EXTENT OF THIS RIDGE OVER
THE UPCOMING DAYS...THE FIRST LOOKING TO DEVELOP TONIGHT INTO FRIDAY
ACROSS EASTERN COLORADO AND WESTERN KANSAS. THIS SHORTWAVE ALSO
LOOKS TO COINCIDE WITH A FRONTAL BOUNDARY STRETCHING SOUTHWARD FROM
A SURFACE LOW OVER MONTANA INTO WESTERN NEBRASKA AND WESTERN KANSAS.
BETTER CHANCES FOR PRECIPITATION LOOK TO BE ACROSS THE WESTERN HALF
OF KANSAS IN THE VICINITY OF THIS BOUNDARY AND SHORTWAVE. THERE IS
STILL SOME UNCERTAINTY AMONGST THE MODELS REGARDING HOW MUCH
MOISTURE AND LIFT WILL BE ABLE TO SPREAD EASTWARD INTO THE FORECAST
AREA ON FRIDAY TO SUPPORT THE DEVELOPMENT OF SOME SCATTERED SHOWERS
AND THUNDERSTORMS. DUE TO THIS UNCERTAINTY...HAVE CHANCE POPS
PRIMARILY FOCUSED OVER NORTH CENTRAL AND CENTRAL KANSAS THROUGH THE
DAY WITH A MOSTLY DRY FORECAST FOR FAR EASTERN KANSAS. COULD START
SEEING ANY SCATTERED PRECIPITATION THAT DEVELOPS SHIFT INTO
NORTHEASTERN KANSAS BY FRIDAY EVENING AS THE SHORTWAVE PIVOTS A BIT
FURTHER EAST ALONG THE RIDGE. THE INCREASED CLOUD COVER ACROSS THE
AREA ON FRIDAY WILL KEEP TEMPERATURES ON THE COOLER SIDE ONCE
AGAIN...WITH AFTERNOON HIGHS LOOKING TO TOP OUT IN THE UPPER 60S TO
LOWER 70S.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 341 PM CDT THU MAY 23 2013
THE MID AND LONG TERM FORECAST PERIOD REMAINS RATHER UNCERTAIN
REGARDING SPECIFIC DETAILS OF LOCATION AND TIMING OF THUNDERSTORM
POTENTIAL...BUT CONFIDENT IN SOME OF THE GENERAL FEATURES AS WELL AS
A TEMPERATURE PATTERN.
THE UPPER LEVEL FLOW PATTERN THIS WEEKEND WILL ACTUALLY BE
CHARACTERIZED BY A RATHER SHARP RIDGE AXIS CENTERED OVER EASTERN
KANSAS WITH A LONG WAVE TROUGH FIRMLY IN PLACE OVER THE WESTERN
CONUS. SEVERAL PIECES OF ENERGY WILL TRANSLATE OUT OF THE WESTERN
TROUGH FROM SATURDAY THROUGH NEXT WEEK...PROVIDING NUMEROUS CHANCES
FOR THUNDERSTORMS THROUGH THE PERIOD. THE PRIMARY CHALLENGE WITH
THIS FORECAST SEEMS TO BE IN INTERPRETING WHICH OF THESE IMPULSES
WILL BE STRONG ENOUGH TO OVERCOME A CAPPING INVERSION ACROSS EASTERN
KANSAS...AS WELL AS ANY PERIODS DURING WHICH THE DEEP LAYER SHEAR
MARKEDLY INCREASES COINCIDENT WITH THE SHORT WAVE TROUGH PASSAGE.
OTHERWISE...TEMPERATURES ARE EXPECTED TO BE GENERALLY IN THE 80S FOR
HIGHS AND 60S FOR LOWS THROUGH THE ENTIRE PERIOD...WITH CLOUD COVER
LARGELY DEPENDENT UPON CONVECTIVE SYSTEMS...AND A RATHER MOIST LOW
LEVEL AIRMASS IN PLACE.
IN TERMS OF SPECIFICS...IT WOULD APPEAR THAT A SHORT WAVE TROUGH
PASSAGE WILL WEAKEN THE UPPER RIDGE ENOUGH ON FRIDAY NIGHT TO
SUPPORT AN MCS ACROSS NEBRASKA...AND PERHAPS EVEN INTO NORTHERN
KANSAS. THE REMNANTS OF THIS MCS MAY IMPACT MAINLY NORTHEAST KANSAS
ON SATURDAY MORNING...BUT PERHAPS MORE IMPORTANTLY ARE EXPECTED TO
PLACE AN OUTFLOW BOUNDARY ACROSS THE FORECAST AREA BY AFTERNOON. THE
EXACT LOCATION OF ANY OUTFLOW WILL FOCUS ANY THUNDERSTORM ACTIVITY
INITIALLY TO THAT LOCATION AND REMAINS UNCERTAIN...BUT INSTABILITY
WILL BE MAXIMIZED ALONG THE BOUNDARY WITH INHIBITION MINIMIZED AND
EXPECT AT LEAST A FEW STORMS TO DEVELOP ALONG ANY REMNANT OUTFLOW IF
IT DOES INDEED EXIST. THE DEEP LAYER SHEAR PROFILE IS NOT PARTICULARLY
STRONG ALTHOUGH IT MAY SUPPORT AT LEAST SOME BRIEF STORM
ORGANIZATION BEFORE COLD POOLS INTERACT. SATURDAY NIGHT CONVECTION
MAY ALSO TRACK ALONG THIS BOUNDARY ACROSS THE AREA OUT OF CENTRAL
NEBRASKA. WILL NEED TO MONITOR THIS ACTIVITY FOR LATE NIGHT
WIND/HAIL POTENTIAL SHOULD IT ORGANIZE INTO AN MCS. UPPER RIDGING IS
FORECAST TO BUILD BACK IN OVER CENTRAL KANSAS IN THE WAKE OF THIS
ACTIVITY...WITH ANY SUNDAY AFTERNOON CONVECTIVE POTENTIAL DEPENDING
UPON A CAP BREAK. INSTABILITY SHOULD STILL BE STRONG ON SUNDAY AND
THE DEEP SHEAR PROFILE SHOULD BE A BIT MORE IMPRESSIVE THAN
SATURDAY...AND COULD SEE SOME SEVERE WEATHER POTENTIAL LATE SUNDAY
INTO SUNDAY NIGHT. LOCALLY HEAVY RAINFALL WILL ALSO BE POSSIBLE
THROUGH THIS PERIOD GIVEN MODERATE TO HIGH PWAT VALUES AND POTENTIAL
FOR STORMS TO FOCUS REPEATEDLY OVER THE SAME GENERAL AREAS.
BEYOND SUNDAY...THE UNCERTAINTY REGARDING SPECIFICS IS JUST TOO
GREAT TO GET BOGGED DOWN IN ANY DETAILS. OPERATIONAL MODELS MAINTAIN
THE BROAD SOUTHWESTERLY UPPER FLOW PATTERN BUT DIVERGE REGARDING THE
EVOLUTION OF THE EJECTION DATE OF THE PRIMARY UPPER LOW ITSELF.
WHENEVER THE HEART OF THIS SYSTEM DOES ENTER THE CENTRAL PLAINS...
WOULD EXPECT A GREATER POTENTIAL OF SEVERE WEATHER WITH INCREASED
DEEP LAYER SHEAR AND PERHAPS A MORE ORGANIZED FOCUS FOR DEVELOPMENT.
HAVE MAINTAINED SEVERAL RATHER SMALL CHANCES FOR PRECIPITATION
THROUGH THE LONG TERM PERIOD BUT THERE IS A CHANCE THAT MUCH OF THE
AREA COULD BE DRY UNTIL THE MAIN TROUGH APPROACHES...IT ALL REALLY
DEPENDS ON WHETHER CAP STRENGTH CAN OUTLAST WEAK SHORT WAVE TROUGH
STRENGTH ON A DAY TO DAY BASIS. EVEN AFTER THE MAIN TROUGH CROSSES
THE PLAINS...IT LOOKS LIKE THE WEATHER PATTERN WILL REMAIN ACTIVE
WITH SOUTHWEST FLOW REMAINING IN PLACE AND A NEW LONG WAVE TROUGH
SETTLING OVER THE WESTERN U.S.
BARJENBRUCH
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1145 PM CDT THU MAY 23 2013
MODELS CONTINUE TO SHOW INCREASING MOISTURE ADVECTION UP THROUGH
CENTRAL KS AS THE LOW LEVEL JET VEERS AROUND MORE TO THE SOUTH.
LATEST SATELLITE SHOWS A BAND OF AC WITHIN THE AXIS OF MOISTURE
ADVECTION. THEREFORE WILL CONTINUE WITH A MENTION OF VCSH AT MHK
BY MID MORNING AS ISENTROPIC PROGS SHOW SOME LIFT WITH LOWERING
COND PRES DEF DEVELOPING ACROSS NORTH CENTRAL KS. THINK TOP AND FOE
WILL REMAIN MAINLY TO THE EAST OF THE BETTER MOISTURE ADVECTION.
THE NAM HAS BACKED OFF ON THE LOW LEVEL SATURATION AND MVFR CIGS.
WITH THE RUC SHOWING SOME CONSISTENCY IN KEEPING CIGS VFR...HAVE
TAKEN OUT THE MENTION OF MVFR CIGS AT MHK.
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...HENNECKE
LONG TERM...BARJENBRUCH
AVIATION...WOLTERS
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
326 AM EDT FRI MAY 24 2013
.Short Term (Now - Saturday)...
Issued at 325 AM EDT Fri May 24 2013
Surface cold front continues to plow on off to the southeast this
morning. Rain showers have long ended across southern Indiana and
central Kentucky, but plenty of low clouds remain in place across
the region. Drier air is trying to work in from the west, but a
persistent north to northeasterly PBL flow is allowing the low
clouds to continue to flow southward this morning. In the near
term, expect mostly cloudy conditions to remain in place, though our
western sections will probably see a little more clearing due to the
closer proximity to the drier air in place to our west.
Temperatures will continue to fall with cold air advection
place...and we expect readings to fall into the mid-upper 40s by
sunrise.
For today, high pressure will slowly build in from the northwest.
Dry punch of air will continue to make headway into the Ohio Valley,
so we should see a rapid decrease in clouds during the morning hours
with mostly sunny skies expected today. Dewpoints will likely drop
into the 30s this afternoon and with a good amount of mixing and
cooler air aloft, we`re likely to see a bit of a temperature
gradient across the region. Afternoon highs will likely only top
out in the 61-66 degree range across the Bluegrass region of central
Kentucky with 65 to 70 degree readings in the I-65 corridor and
points west. Surface winds will be out of the N to NE and will
slacken later in the afternoon and into the evening hours.
For tonight, high pressure and light winds will be in place which
should set up a good radiational cooling period. The question
remains whether we`ll see the development of fog or a potential
frost. From a climatological perspective, the threat of frost is
fairly low here in KY/IN. For the most part, it looks like
temperatures will probably remain warm enough that we`ll see mostly
patchy fog develop. However, some of our eastern counties may get a
touch of frost...especially in our typical cold spots. For this
reason, we will issue a special weather statement this morning
highlighting the potential frost threat in the typical colder spots
in the eastern Bluegrass region. Lows tonight will likely be in the
upper 30s in the east with lower 40s in the central and western
sections.
Quiet and warmer conditions are expected for Saturday as high
pressure moves on off to the east. This should kick our surface
winds around to the south and eventually the southwest.
Temperatures should moderate a bit on Saturday with highs in the
65-70 degree range in the Bluegrass with 70 to 75 in the central and
western sections of the forecast area.
.Long Term (Saturday Night through Thursday)...
Issued at 310 AM EDT Fri May 24 2013
A amplified yet slowly progressive 500mb pattern will feature deep
troughs across New England and the Pacific Northwest late Saturday.
Eventually, ridging over the western plains will expand towards the
Lower Ohio Valley. This will enable temperatures to warm
substantially beginning Monday. High temperatures may actually
approach 90 towards the end of the next work week.
Canadian high pressure ridge axis will lie right over the Great
Lakes late Saturday, extending southward across the Commonwealth.
Cool weather with low dewpoints will continue through Sunday, along
with light winds. Despite the possibility of some increasing high
cloudiness associated with a warm front to our southwest, lows early
Sunday will fall well down into the lower to mid 50s.
Quite a bit of uncertainty and disagreement exists between some of
the long range guidance for the Sunday through Tuesday time frame.
Overall, warmer more moist air will attempt to move northeast into
the Lower Ohio Valley. However, a deep slow moving low over New
England and persistent northwest flow aloft over the Commonwealth
will retard the northeast progress of this boundary. It is likely
during the first couple of days of next week that several convective
clusters will develop across the midwest, aided by moisture
advection and the presence of a nocturnal low level jet. These
periodic thunderstorms may slide southeast, bringing at least a
chance of difficult-to-time thunderstorms beginning Sunday afternoon
and possibly continuing through Tuesday.
Both the ECMWF and the GFS forecast the surface boundary to stretch
early Sunday from northern Missouri southeast towards central
Tennessee. The consistent ECMWF has been slower in bringing this
boundary north across the Commonwealth than the GFS. However, by
Tuesday afternoon, both of these models have this boundary as far
north as southern Ohio. Will continue our forecast of at least a
chance of thunderstorms Sunday afternoon through Tuesday, with an
admittedly low confidence on attempting to time any areas of
convection moving southeastward along this boundary.
Highs on Sunday will likely remain in the 70s, warming to the lower
to mid 80s by Tuesday. For Wednesday and Thursday, mid-summer like
ridging will develop over the Tennessee Valley. Expect that these
two days will stay dry with quite warm temperatures in the mid to
upper 80s.
&&
.Aviation (06Z TAF Issuance)...
Issued at 115 AM EDT Fri May 24 2013
MVFR ceilings are expected to persist at the terminals through the
overnight period. Previous thinking from earlier was for clouds to
clear out in the 07-09Z time frame. However, latest trajectory data
from the RAP and LMK local WRF model suggests that the low-level PBL
will be more northerly to a little northeasterly overnight. IR
satellite imagery suggests that this may be correct as cloud cover
has not really eroded all that much to our north and more clouds up
over northern Indiana are heading southward. Upstream observations
show that ceilings are holding around 2kft AGL and we expect these
conditions to continue through much of the overnight period. Feel
that ceilings will eventually mix out and go back to VFR by around
24/11Z or so and then continue throughout the day. Surface winds
for the next few hours will remain out of the NNW to N at 10-13kts
with occasional gusts up to 15-18kts. Winds look to shift to the
northeast during the daylight hours and then diminish near toward
the end of the TAF period.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Short Term.......MJ
Long Term........JSD
Aviation.........MJ
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
117 AM EDT FRI MAY 24 2013
...Updated Aviation Discussion...
.Forecast Update...
Issued at 115 AM EDT Fri May 24 2013
Current forecast still pretty much on track. Will be make a few
changes to the cloud grids as sky cover will likely remain mostly
cloudy for a good portion of the night. Latest RAP and LMK WRF data
showing more of a north to north-northeast low level PBL flow which
should keep clouds in here a little longer than previously
forecast. This will keep temperatures from dropping as fast as
previously thought. So will also make some minor adjustments there
as well.
Update issued at 1210 AM EDT Fri May 24 2013
Radar and surface observations show that rain showers have been
diminishing quite rapidly across the region as the secondary surface
cold pushes southward through the region. Latest 11-3.9 micron
satellite imagery shows deck of low clouds across the forecast area
and extends back into central Indiana. Based on satellite imagery,
back edge of clouds look to clear the Ohio River around 3AM EDT and
then clear much of southern Kentucky by sunrise. Have updated the
forecast based on those cloud trends and also have removed PoPs from
most areas. Temperatures with the new airmass coming in are quite
cool for mid-late May. Readings have cooled into the lower 50s
across our far northern areas and have dropped into the mid-upper
50s across northern Kentucky. Based on the short-term consensus
model runs, looks like min temperatures will cool into the lower 40s
across southern Indiana with upper 40s across Kentucky by sunrise.
Winds will remain out of the NNW to N at 10 to 15 mph.
&&
.Short Term (Now - Friday Night)...
Issued at 300 PM EDT Thu May 23 2013
A deep trough over the Great Lakes is currently pivoting, with the
axis on track to pass over the forecast area this evening and
tonight. At the surface, a cold front is dropping southeastward
through central Indiana. This front is forecast to exit our
southeast forecast area by about midnight tonight. Scattered showers
are developing along and ahead of the front. This will continue
across our area the rest of this afternoon and into the evening
hours. Surface-based instability is rather weak and these showers
are capped at or just above the freezing level. Could see an
isolated thunderstorm, but chances are rather low. Activity will
dissipate late this evening and clouds will slowly diminish from
northwest to southeast overnight.
Winds will become northwesterly with the frontal passage, then
northerly by daybreak Friday. Dry and much cooler air will begin to
work into the region from the northwest, with temperatures dropping
into the middle and upper 40s tonight. Despite almost unlimited sun
on Friday, temperatures will be rather cool, ranging from the middle
60s to around 70 degrees. High pressure will build directly overhead
Friday night. Clear skies and light winds will provide for quite
chilly conditions, with lows bottoming out in the upper 30s and
lower 40s. Typically cooler valleys could drop into the middle 30s.
.Long Term (Saturday through Thursday)...
Issued at 310 PM EDT Thu May 23 2013
High confidence forecast for Saturday with a 1030mb surface high
over Lake Michigan, and extending south into the Ohio Valley. Expect
plenty of sunshine and below-normal temps. Given forecast soundings,
low-level thicknesses, and typical behavior in NE low-level flow,
believe that GFS MOS temps are too warm. Have leaned more toward the
cooler NAM MOS, with highs ranging from the upper 60s over the
Bluegrass to the mid 70s near Bowling Green.
Confidence heads downhill quickly beginning on Saturday night thanks
to NW flow aloft and divergent model solutions. There is consensus
that a NW-SE oriented surface boundary will develop somewhere across
the Ohio and/or Tennessee Valleys. However, the GFS leans more
toward a warm front developing over the Ohio Valley and lifting
north by Monday night, while the ECMWF has the front to our south
initially and not lifting out of the Ohio Valley until Wed/Thu. With
a shortwave ridge axis over the Plains, there is at least a decent
chance that MCSs will develop west of the Mississippi and roll SE
along the front. Confidence is limited by the difficulty in timing
the development of these complexes, and determining whether they
will hold together as they move into what will be a less favorable
environment. Therefore we will generally advertise slight chance
POPs, only bumping up to a 30 POP west of I-65 for Monday. Temp
forecast will undercut the GFS MOS as we do not believe the warm
front will lift northward that quickly. Will stay below normal
through Monday.
Upper ridging will build from the southern Plains beginning on
Tuesday and continue through at least Thursday. Expect temps
trending back above normal for late May, and will continue diurnal
slight chance POPs. Greatest bust potential will be from southern
Indiana into the Bluegrass, where the cooler and wetter pattern
could persist an additional day or two if the warm front is slower to
lift out.
&&
.Aviation (06Z TAF Issuance)...
Issued at 115 AM EDT Fri May 24 2013
MVFR ceilings are expected to persist at the terminals through the
overnight period. Previous thinking from earlier was for clouds to
clear out in the 07-09Z time frame. However, latest trajectory data
from the RAP and LMK local WRF model suggests that the low-level PBL
will be more northerly to a little northeasterly overnight. IR
satellite imagery suggests that this may be correct as cloud cover
has not really eroded all that much to our north and more clouds up
over northern Indiana are heading southward. Upstream observations
show that ceilings are holding around 2kft AGL and we expect these
conditions to continue through much of the overnight period. Feel
that ceilings will eventually mix out and go back to VFR by around
24/11Z or so and then continue throughout the day. Surface winds
for the next few hours will remain out of the NNW to N at 10-13kts
with occasional gusts up to 15-18kts. Winds look to shift to the
northeast during the daylight hours and then diminish near toward
the end of the TAF period.
&&
.LMK WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
KY...NONE.
$$
Update...........MJ
Short Term.......MJP
Long Term........RAS
Aviation.........MJ
AREA FORECAST DISCUSSION
NWS GRAY ME
530 PM EDT FRI MAY 24 2013
.SYNOPSIS...
A COLD FRONT WILL PUSH OFFSHORE AND STALL THIS EVENING. LOW
PRESSURE WILL DEVELOP ON THE FRONT NEAR CAPE COD AND WILL SLOWLY
DRIFT NORTH THROUGH THE GULF OF MAINE SATURDAY AND SATURDAY NIGHT.
LOW PRESSURE WILL ACCELERATE NORTH INTO LABRADOR ON SUNDAY. HIGH
PRESSURE WILL BUILD IN FROM THE WEST SUNDAY NIGHT THROUGH MONDAY.
HIGH PRESSURE WILL SHIFT OFFSHORE ON TUESDAY. A WARM FRONT WILL
APPROACH FROM THE SOUTHWEST TUESDAY NIGHT AND WEDNESDAY AND WILL
PUSH EAST OF THE REGION WEDNESDAY NIGHT.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
UPDATE...
HAVE UPDATED GRIDS BASED ON CURRENT CONDITIONS...WITH THE COLD
FRONT SLIPPING THROUGH THE COASTLINE AS OF 21Z. LOW PRESSURE WILL
CONTINUE TO TAKE SHAPE OFF THE NEW ENG COASTLINE THEREAFTER...WITH
CYCLOGENESIS OCCURRING NEAR CAPE COD THIS EVENING.
LATEST HRRR MODEL PICKING UP WELL ON CONVECTIVE SEGMENTS CROSSING
THE FORECAST AREA AT THIS TIME. THIS MODEL DEPICTS MORE AREAS OF
RAIN MOVING THROUGH THE REGION LATE TONIGHT AFTER A BREAK IN THE
ACTION LATER THIS EVENING.
WILL CONTINUE TO MONITOR COLD AIR RUSHING INTO THE MTNS FROM
CANADA OVERNIGHT. THERE COULD BE SOME MIXED SNOW AND RAIN OVER THE
HIGHER TERRAIN FOR THIS STORM WHICH IS VERY SIMILAR TO THE MAY
26TH 1967 EVENT.
HAVE ADJUSTED WINDS AND TEMPS FOR THE HIGHER TERRAIN. WINDS WILL
BECOME RATHER GUSTY FOR ANY HIKERS OUT OF THE NORTH AND NORTH OVER
THE NEXT COUPLE OF DAYS...WITH SOME SNOW ACROSS THE HIGH TERRAIN.
PREV DISC...
COLD FRONT CURRENTLY MOVING EAST THROUGH EASTERN NEW HAMPSHIRE
AND NORTHWEST MAINE AND THIS BOUNDARY WILL CONTINUE TO PUSH OFF TO
THE EAST THROUGH THE REMAINDER OF THE AFTERNOON. FRONT WILL STALL
OFFSHORE THIS EVENING AND WILL BE THE FOCUS OF LIGHT TO MODERATE
RAINFALL IN MID COAST AND CENTRAL MAINE DURING THE REMAINDER OF
THE AFTERNOON INTO THIS EVENING. WILL SEE A BRIEF BREAK IN THE
ACTION ACROSS NEW HAMPSHIRE DURING THE REST OF THE AFTERNOON
BEFORE NEXT BATCH OF PRECIP EDGES IN FROM THE WEST. WILL TAKE SOME
TIME FOR LOW PRESSURE TO GET SPUN UP OVERNIGHT SO THIS BREAK MAY
TRANSLATE EASTWARD INTO WESTERN MAINE FOR THE EVENING HOURS BEFORE
850 OVER-RUNNING GETS GOING IN EARNEST ACROSS WESTERN MAINE AFTER
MIDNIGHT.
12Z MODELS TRENDING FARTHER WEST WITH AXIS OF HEAVIEST PRECIP AND
COMING INTO LINE WITH LAST NIGHT 00Z ECMWF. 24 HOUR QPF FOR THE
MOUNTAINS AND CONNECTICUT VALLEY DOWN TO AROUND AN INCH TO 1.5
INCHES THROUGH 00Z SUN. WITH THIS IN MIND...DOESN`T APPEAR
FLOODING WILL BE AN ISSUE CONSIDERING THE BREAK IN THE ACTION
THIS AFTERNOON AND LONG DURATION OF THE EVENT ITSELF...SO HOLDING
OFF ON ANY WATCHES AT THIS POINT IN TIME.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
RAIN WILL CONTINUE SATURDAY THROUGH SATURDAY NIGHT AS SURFACE LOW
BECOMES TRAPPED UNDER UPPER LEVEL SYSTEM AND MEANDERS AROUND THE
GULF OF MAINE THROUGH SUNDAY MORNING. MAY SEE SOME WET SNOW OVER
THE HIGHEST TERRAIN AT SOME POINT ON SATURDAY IN FAR WESTERN ZONES BUT
ENOUGH WARM AIR WRAPS AROUND THE SYSTEM THAT THIS WOULD BE FAIRLY
BRIEF. BETTER CHANCE FOR THIS WOULD BE IN THE GREENS OF VERMONT
AND THE DACKS. WILL BE A COLD AND BLUSTERY DAY WITH TEMPS HOLDING
IN THE 40S IN MOST AREAS AND SHOWING LITTLE CHANGE SATURDAY NIGHT.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
UPR LVL AND SFC LOWS LIFTING NE ON SUNDAY WITH STEADIER PRCP
BECOMING MORE SCT IN NATURE AND LIGHTER IN INTENSITY. ANY LEFTOVER
SHRA ENDING SUNDAY NGT AS THE SYSTEM MOVES INTO THE MARITIMES.
MEMORIAL DAY LOOKS LIKE FAIR WX NOW WITH SYSTEM PULLING OUT FAR
ENOUGH TO THE NE. STILL SOME CYCLONIC FLOW ALOFT AND SOME LEFTOVER
MOISTURE THAT COULD PRODUCE SOME CLOUDINESS ESPECIALLY IN THE N/MT
ZONES DUE TO UPSLOPING NW SFC WINDS. MIGHT SEE AN ISOLD SHRA IN
THE N/MT ZONES OTRW NO PRCP EXPECTED ON MEMORIAL DAY.
HIGH PRES AND UPR LVL RIDGE BUILD IN FOR TUESDAY INTO WEDNESDAY.
THE UPR LVL RIDGE HOLDS 0N OVER THE ERN U.S. BUT A SERIES OF WEAK
UPR LVL SHORT WAVE TROFS DRIVE THRU THE RIDGE FOR LATE WEDNESDAY
AND THURSDAY. THIS FORMS A WRM FRONTAL BOUNDARY TO OUR S THAT
LIFTS N AND WILL PROVIDE SOME CLOUDINESS AND ISOLD TO SCT SHRA
FROM LATE WEDNESDAY THRU THURSDAY. THE UPR LVL RIDGE BECOMES
BETTER ESTABLISHED OVER THE E COAST THURSDAY NGT AND FRIDAY AS THE
SHORT WAVES EXIT THE COAST. THIS SHOULD ALLOW WRM AIR TO CONT
MOVING IN FROM THE SW. STILL CAN`T RULE OUT PSBL SHRA DUE TO WRM
FNT MOVING THRU.
GENERALLY USED BLEND OF GFS40/NAM/MET/MAV/HPC QPF FOR PERIODS 4
AND 5 THEN GFS40, GMOS, HPC QPF, MEX MOS AND WNA4 FOR THE REST OF
THE LONG TERM FCST.
&&
.AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
SHORT TERM...IFR/LIFR CEILINGS TONIGHT THROUGH SATURDAY NIGHT.
LONG TERM /SUNDAY THROUGH WEDNESDAY/...MVFR TO PSBL IFR IN SHRA
THAT WILL BE TAPERING OFF SUNDAY INTO SUNDAY NGT. MAINLY VFR
MONDAY THRU TUESDAY AND MOST OF WEDNESDAY.
&&
.MARINE...
SHORT TERM...HAVE EXTENDED SCA TO GO RIGHT THROUGH SATURDAY.
ALTHOUGH WINDS DROP OFF AT SOME POINT...WAVES WILL REMAIN AT LEAST
IN THE 3 TO 5 FOOT RANGE...WITH GREATER SEAS OUT OVER THE OPEN WATERS.
COASTAL FLOOD ADVISORY FOR MINOR SPLASH-OVER AROUND THE TIME OF
HIGH TIDE.
LONG TERM /SUNDAY THROUGH WEDNESDAY/...SCA WIND GUSTS AND SEAS
PSBL SUNDAY THRU MOST OF SUNDAY NGT THEN HIGH PRES DROPS
CONDITIONS BELOW SCA LEVELS MONDAY THRU WEDNESDAY.
&&
.FIRE WEATHER...
NO PROBLEMS NOTED.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...COASTAL FLOOD ADVISORY FROM 10 PM THIS EVENING TO MIDNIGHT EDT
TONIGHT FOR MEZ023>028.
NH...COASTAL FLOOD ADVISORY FROM 10 PM THIS EVENING TO MIDNIGHT EDT
TONIGHT FOR NHZ014.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT SATURDAY FOR ANZ150>154.
&&
$$
CANNON
AREA FORECAST DISCUSSION
NWS GRAY ME
1218 AM EDT FRI MAY 24 2013
.SYNOPSIS...
A COLD FRONT WILL SLOWLY CROSS THE REGION TONIGHT WILL STALL OFF
THE COAST ON FRIDAY. LOW PRESSURE WILL DEVELOP ON THE FRONT SOUTH
OF CAPE COD FRIDAY NIGHT AND SLOWLY MOVE NORTH THROUGH THE GULF OF
MAINE THROUGH SUNDAY MORNING. LOW PRESSURE WILL CONTINUE NORTH
THROUGH THE MARITIMES SUNDAY NIGHT. HIGH PRESSURE WILL BUILD IN
FROM THE WEST MONDAY AND WILL SHIFT OFFSHORE ON TUESDAY. A WARM
FRONT WILL APPROACH FROM THE SOUTHWEST ON WEDNESDAY.
&&
.NEAR TERM /UNTIL 9 AM THIS MORNING/...
1205 AM...JUST A QUICK UPDATE TO ADJUST POPS AND TEMPS A BIT
OVERNIGHT...AND TO FOCUS ON BEST CH OF HEAVIER DOWNPOURS IN THE
06-13Z TIME FRAME AS 500 MB SH COMBINES WITH MID-LVL JET AND HIGH
PWATS...APPROACHING 200% OF NORMAL COM TO TOGETHER TO PRODUCE A
SURGE OF HEAVY RAINFALL...WHICH WILL DEVELOP AFTER MIDNIGHT AND LKLY
AFFECT MORNING COMMUTE. 00Z NAM12 AND LATEST HRRR FOCUS THE BULK
OF THE PRECIP CLOSER TO THE COAST...WHERE THE GROUND CAN HANDLE IT
BETTER. HOWEVER...COULD CAUSE SOME LOCALIZED PROBLEMS...PONDING ON
THE ROADS AND IN URBAN AREAS.
UPDATE...
HAVE UPDATED GRIDS BASED ON CURRENT CONDITIONS. RADAR CONTS TO
SHOW AREAS OF SHOWERS AND ISOLD TSTMS OVER THE NRN MTNS WHERE WE
HAVE ISSUED AN AREAL FLOOD ADVISORY. OVER SRN NH...THE ECHOES CONT TO
WEAKEN AS THEY HEAD NORTH...DESPITE A PRECIPITABLE WATER LEVEL
AXIS OF 1.6" OVER THE REGION.
LATEST HRRR RUN CONTS TO SHOW PCPN STREAMING IN FROM THE SOUTH
OVERNIGHT...ALONG AND AHEAD OF APPROACHING COLD FRONT. CATEGORICAL
POPS WILL REMAIN IN THE GRIDS OVERNIGHT WITH PATCHY/AREAS OF FOG.
EXPECT AROUND AN INCH OR SO OF RAINFALL OVER THE COASTAL AREAS
WHICH REMAINS WELL BELOW FLASH FLOOD GUIDANCE.
PREV DISC...
COLD FRONT APPROACHING FROM THE WEST WILL MAKE FOR A WET AND
BREEZY NIGHT ACROSS THE REGION. SCATTERED SHOWERS AND SOME
THUNDERSTORMS WILL GRADUALLY CHANGE TO A WIDESPREAD RAIN OVERNIGHT
AS THE FRONT SLOWLY CROSSES THE AREA. EXPECT THUNDERSTORM ACTIVITY
TO BE MAINLY CONFINED TO NEW HAMPSHIRE LATE THIS AFTERNOON AND
THIS EVENING AS MARINE LAYER PERSISTS ACROSS MOST OF MAINE. CAN`T
RULE OUT A RUMBLE OF THUNDER OVERNIGHT BUT SHOULD BE ISOLATED AND
HAVE NOT INCLUDED THIS IN THE FORECAST AFTER THIS EVENING. EXPECT
OVERNIGHT LOWS TO BE UNIFORM ACROSS THE REGION WITH MOST AREAS
DIPPING INTO THE MID 50S TO NEAR 60.
&&
.SHORT TERM /9 AM THIS MORNING THROUGH 6 PM SATURDAY/...
FRONT WILL STALL JUST OFF THE COAST ON FRIDAY WITH RAIN CONTINUING
THROUGH THE DAY ACROSS THE FORECAST AREA. NOT EXPECTING
TEMPERATURES TO MOVE MUCH FROM OVERNIGHT LOWS WITH MOST LOCATIONS
ONLY REACHING THE UPPER 50S TO LOWER 60S. RAIN CONTINUES FRIDAY
NIGHT AS LOW PRESSURE TRACKS NORTH ALONG THE FRONT. FOCUS WILL
TURN TO AREA RIVERS IN NORTHERN ZONES WHERE STORM TOTALS COULD
WILL FALL IN THE THE 2 TO 4 INCH RANGE BY LATE ON SUNDAY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
CUTOFF AND SFC LOW WILL DRIFT SLOWLY NE THRU THE WEEKEND
CONTINUING PRCP ACROSS THE FCST AREA WITH THE POTENTIAL FOR HEAVY
RAINFALL. MODELS SHOWING MAX QPF ACROSS THE N/MT ZONES TO WRN NH
ZONES. GFS MUCH HIGHER ON QPF...WITH OTHER MODELS PREFERRED. USED
HPC QPF FOR A COMPROMISE. CUTOFF AND SFC LOWS MOVE NE OF THE AREA
MONDAY WITH IMPROVING WX...BUT STILL COOL AIR AND CYCLONIC FLOW
ALOFT ALONG WITH FAIRLY AMPLE RH COULD PRODUCE SOME CLOUDS AND
PSBL -SHRA EVEN ON MONDAY. FOR NOW WILL GO WITH SLGT CHC.
AN UPR LVL AND SFC RIDGE BUILD IN TUESDAY FINALLY BRINGING DRY WX
WITH WARMING TEMPS. AN UPR LVL SHORT WAVE TROF SLIDES E THRU THE
UPR LVL RIDGE LATE WEDNESDAY AND WEDNESDAY NGT...BRINGING ISOLD TO
SCT SHRA TO THE REGION WEDNESDAY NGT AND THURSDAY.
GENERALLY USED BLEND OF GFS40/NAM, MET/MAV & HPC QPF FOR DAYS 4
AND 5 THEN A BLEND OF GFS40, GMOS, MEX/ECE FOR THE REST OF THE
LONG TERM FCST.
&&
.AVIATION /04Z FRIDAY THROUGH TUESDAY/...
SHORT TERM...IFR/LIFR CEILINGS/VSBY TONIGHT THROUGH FRIDAY.
LONG TERM /SATURDAY THROUGH TUESDAY/...IFR/LIFR SATURDAY THRU MUCH
OF SUNDAY...IMPROVING TO VFR WITH PSBL MVFR ON MONDAY THEN VFR
TUESDAY.
&&
.MARINE...
SHORT TERM...SCA IN EFFECT THROUGH FRIDAY TONIGHT.
LONG TERM /SATURDAY THROUGH TUESDAY/...NE WINDS AHEAD OF
APPROACHING LOW AND SEAS LIKELY AT SCA LEVELS SATURDAY AND MAY
NEED TO EXTEND THE SCA THRU THE DAY. WINDS LET UP AND BACK TO THE
NW SLOWLY SATURDAY NGT THRU MONDAY...LIKELY DROPPING BELOW SCA
LEVELS BY LATE SATURDAY NGT OR EARLY SUNDAY. SEAS WILL BE SLOWER
TO DROP OFF. HIGH PRES PROVIDES RELATIVELY CALMER WINDS AND SEAS
ON TUESDAY.
&&
.FIRE WEATHER...
NO PROBLEMS NOTED.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 8 AM EDT SATURDAY FOR ANZ150>154.
&&
$$
SYNOPSIS...
NEAR TERM...CEMPA
SHORT TERM...
LONG TERM...
AVIATION...
MARINE...
FIRE WEATHER...
HYDROLOGY...
AREA FORECAST DISCUSSION...UPDATED
NWS PITTSBURGH PA
628 PM EDT FRI MAY 24 2013
.SYNOPSIS...
DRY AND COOL WEATHER CAN BE EXPECTED FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH SATURDAY/...
ADJUSTMENTS TO WINDS OVERNIGHT...JUST WEAKENED THEM A BIT FASTER.
TRIED TO TIME THE DECAYING OF CLOUD DECK...WITH LOW CONFIDENCE.
WESTERN EDGE OF CLOUDS ARE ERODING QUICKLY...BUT WITH CYCLONIC
FLOW AND COLD AIR ALOFT...TIMING IS DIFFICULT.
PREVIOUS DISCUSSION...
THE UPPER LEVEL TROUGH WILL CONTINUE TO PIVOT ACROSS THE REGION
THROUGH THE AFTERNOON AND EVENING AS HIGH PRESSURE TRIES TO BUILD
OVERHEAD AT THE SURFACE. COLD NORTHWEST FLOW CONTINUES TO KEEP
CLOUD COVER OVER MUCH OF THE FORECAST AREA THROUGH THIS
AFTERNOON...WHICH IS RIGHT IN LINE WITH THE LATEST RUC FORECAST.
WITH CLOUD COVER STILL IN PLACE...CONTINUED A DOWNWARD TREND IN
THE HIGH TEMPERATURES FOR THE AFTERNOON...WITH PIT LIKELY TO BE
VERY CLOSE TO BREAKING IT`S LOW HIGH TEMPERATURES RECORD FROM
1877.
THE MOST RECENT MODEL RUNS CONTINUE TO SUGGEST THAT CLOUDS WILL
EVENTUALLY DIMINISH OVER THE ENTIRE REGION...LASTING LONGEST IN
THE RIDGES. HOW FAST THE CLOUDS DIMINISH WILL PLAY A BIG ROLE IN
HOW QUICKLY TEMPERATURES DROP OVERNIGHT. HOWEVER...SINCE
TEMPERATURES ARE ALREADY LOWER THAN ORIGINALLY FORECAST...CLEARING
SKIES SHOULD ALLOW LOWS IN THE LOW TO MID 30`S TO BE REALIZED
RELATIVELY QUICKLY. FOR NOW...CONTINUED THE FROST/FREEZE AS
IS...ALTHOUGH SOME COUNTIES MAY NEED TO BE UPGRADED TO A FREEZE IF
SKIES CLEAR SOONER AND WINDS DECOUPLE.
HIGH PRESSURE WILL BUILD OVERHEAD SATURDAY BRINGING A CLEAR DAY
BUT NORTHWEST FLOW WILL KEEP TEMPERATURES 10 TO 15 BELOW SEASONAL
AVERAGES.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
HIGH PRESSURE WILL CONTINUE TO DOMINATE THROUGH THE SHORT TERM
PERIOD. TEMPERATURES WERE KEPT 5 DEGREES BELOW SEASONAL AVERAGES
SUNDAY...BUT MODERATED CLOSER TO NORMAL BY MONDAY. AN APPROACHING
WARM FRONT COULD BRING THE CHANCE FOR A SHOWER IN THE SOUTHERN
PORTIONS OF THE FORECAST AREA LATE MONDAY BUT FOR NOW...LEFT LOW
END POPS.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
A WARM FRONT MOVING NORTH ACROSS THE DISTRICT TUESDAY WILL BRING
A CHANCE OF SHOWERS AND THUNDERSTORMS THROUGH WEDNESDAY. AS THE WARM
FRONT MOVES NORTH OF THE FORECAST AREA THURSDAY WARM AND MORE HUMID
CONDITIONS WILL RETURN WITH HIGH TEMPERATURES INTO THE 80S THROUGH
FRIDAY. THERE WILL BE A SLIGHT CHANCE OF DIURNAL THUNDERSTORMS
THURSDAY AND FRIDAY.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
GENERAL MVFR TO VFR STRATOCU REMAINS IN PLACE THIS EVENING WITH
KFKL STILL BELOW 2000 FT AT THIS HOUR. GENERAL BROKEN VFR TO MVFR
CEILINGS CAN BE EXPECTED THIS EVENING. CEILINGS COULD SLOWLY LOWER
AFTER SUNSET AS GUSTY WINDS DIMINISH. NORTHERLY FLOW OFF THE LAKES
WILL TEND TO KEEPS SOME CLOUDINESS ACROSS THE DISTRICT INTO SATURDAY
MORNING.
.OUTLOOK.../SATURDAY THROUGH TUESDAY/...
HIGH PRESSURE WILL MAINTAIN GENERAL VFR THROUGH MONDAY. A WARM FRONT
WILL BRING A CHANCE OF SHOWERS AND THUNDERSTORMS FOR TUESDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...FREEZE WARNING FROM 3 AM TO 8 AM EDT SATURDAY FOR MDZ001.
OH...FROST ADVISORY FROM 3 AM TO 8 AM EDT SATURDAY FOR OHZ039>041-
048>050-057>059-068-069.
PA...FROST ADVISORY FROM 3 AM TO 8 AM EDT SATURDAY FOR PAZ020-021-
029-031-073-075.
FREEZE WARNING FROM 3 AM TO 8 AM EDT SATURDAY FOR PAZ007>009-
013>016-022-023-074-076.
WV...FROST ADVISORY FROM 3 AM TO 8 AM EDT SATURDAY FOR WVZ001>004-
012-021-022.
FREEZE WARNING FROM 3 AM TO 8 AM EDT SATURDAY FOR WVZ023-041.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
326 PM EDT FRI MAY 24 2013
.SYNOPSIS...
DRY AND COOL WEATHER CAN BE EXPECTED FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH SATURDAY/...
THE UPPER LEVEL TROUGH WILL CONTINUE TO PIVOT ACROSS THE REGION
THROUGH THE AFTERNOON AND EVENING AS HIGH PRESSURE TRIES TO BUILD
OVERHEAD AT THE SURFACE. COLD NORTHWEST FLOW CONTINUES TO KEEP
CLOUD COVER OVER MUCH OF THE FORECAST AREA THROUGH THIS
AFTERNOON...WHICH IS RIGHT IN LINE WITH THE LATEST RUC FORECAST.
WITH CLOUD COVER STILL IN PLACE...CONTINUED A DOWNWARD TREND IN
THE HIGH TEMPERATURES FOR THE AFTERNOON...WITH PIT LIKELY TO BE
VERY CLOSE TO BREAKING IT`S LOW HIGH TEMPERATURES RECORD FROM
1877.
THE MOST RECENT MODEL RUNS CONTINUE TO SUGGEST THAT CLOUDS WILL
EVENTUALLY DIMINISH OVER THE ENTIRE REGION...LASTING LONGEST IN
THE RIDGES. HOW FAST THE CLOUDS DIMINISH WILL PLAY A BIG ROLE IN
HOW QUICKLY TEMPERATURES DROP OVERNIGHT. HOWEVER...SINCE
TEMPERATURES ARE ALREADY LOWER THAN ORIGINALLY FORECAST...CLEARING
SKIES SHOULD ALLOW LOWS IN THE LOW TO MID 30`S TO BE REALIZED
RELATIVELY QUICKLY. FOR NOW...CONTINUED THE FROST/FREEZE AS
IS...ALTHOUGH SOME COUNTIES MAY NEED TO BE UPGRADED TO A FREEZE IF
SKIES CLEAR SOONER AND WINDS DECOUPLE.
HIGH PRESSURE WILL BUILD OVERHEAD SATURDAY BRINGING A CLEAR DAY
BUT NORTHWEST FLOW WILL KEEP TEMPERATURES 10 TO 15 BELOW SEASONAL
AVERAGES.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
HIGH PRESSURE WILL CONTINUE TO DOMINATE THROUGH THE SHORT TERM
PERIOD. TEMPERATURES WERE KEPT 5 DEGREES BELOW SEASONAL AVERAGES
SUNDAY...BUT MODERATED CLOSER TO NORMAL BY MONDAY. AN APPROACHING
WARM FRONT COULD BRING THE CHANCE FOR A SHOWER IN THE SOUTHERN
PORTIONS OF THE FORECAST AREA LATE MONDAY BUT FOR NOW...LEFT LOW
END POPS.
&&
.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
A WARM FRONT MOVING NORTH ACROSS THE DISTRICT TUESDAY WILL BRING
A CHANCE OF SHOWERS AND THUNDERSTORMS THROUGH WEDNESDAY. AS THE WARM
FRONT MOVES NORTH OF THE FORECAST AREA THURSDAY WARM AND MORE HUMID
CONDITIONS WILL RETURN WITH HIGH TEMPERATURES INTO THE 80S THROUGH
FRIDAY. THERE WILL BE A SLIGHT CHANCE OF DIURNAL THUNDERSTORMS
THURSDAY AND FRIDAY.
&&
.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
GENERAL MVFR TO VFR STRATOCU REMAINS IN PLACE THIS EVENING WITH
KFKL STILL BELOW 2000 FT AT THIS HOUR. GENERAL BROKEN VFR TO MVFR
CEILINGS CAN BE EXPECTED THIS EVENING. CEILINGS COULD SLOWLY LOWER
AFTER SUNSET AS GUSTY WINDS DIMINISH. NORTHERLY FLOW OFF THE LAKES
WILL TEND TO KEEPS SOME CLOUDINESS ACROSS THE DISTRICT INTO SATURDAY
MORNING.
.OUTLOOK.../SATURDAY THROUGH TUESDAY/...
HIGH PRESSURE WILL MAINTAIN GENERAL VFR THROUGH MONDAY. A WARM FRONT
WILL BRING A CHANCE OF SHOWERS AND THUNDERSTORMS FOR TUESDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...FREEZE WARNING FROM 3 AM TO 8 AM EDT SATURDAY FOR MDZ001.
OH...FROST ADVISORY FROM 3 AM TO 8 AM EDT SATURDAY FOR OHZ039>041-
048>050-057>059-068-069.
PA...FROST ADVISORY FROM 3 AM TO 8 AM EDT SATURDAY FOR PAZ020-021-
029-031-073-075.
FREEZE WARNING FROM 3 AM TO 8 AM EDT SATURDAY FOR PAZ007>009-
013>016-022-023-074-076.
WV...FROST ADVISORY FROM 3 AM TO 8 AM EDT SATURDAY FOR WVZ001>004-
012-021-022.
FREEZE WARNING FROM 3 AM TO 8 AM EDT SATURDAY FOR WVZ023-041.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1228 PM EDT FRI MAY 24 2013
.SYNOPSIS...
DRY AND COOL WEATHER CAN BE EXPECTED FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
LIGHT SHOWERS/DRIZZLE WILL CONTINUE TO DIMINISH THROUGH THE
AFTERNOON AS DRIER AIR WITH THE APPROACHING HIGH PRESSURE BEGINS
TO BUILD OVERHEAD. THE BIGGEST CONCERN FOR THE NEAR TERM IS THE
IMPACT CLOUD COVER WILL HAVE ON TEMPERATURES TODAY THROUGH THE
OVERNIGHT AND HOW THIS WILL FURTHER IMPACT FROST/FREEZE ACROSS THE
FORECAST AREA. THE MOST RECENT RUNS OF THE HRRR AND RUC SUGGEST THAT
MOISTURE TRAPPED UNDER THE LOW LEVEL INVERSION WILL STRUGGLE TO
MIX OUT TODAY...KEEPING CLOUD COVER OVER MUCH OF THE REGION LONGER
THAN ORIGINALLY ANTICIPATED. HAVE ALREADY LOWERED HIGH
TEMPERATURES A FEW DEGREES TODAY WITH THE CONTINUED COLD ADVECTION
AND CLOUD COVER. DEPENDING ON WHEN THE LOWER LEVELS DRY
OUT...TEMPERATURES MAY HAVE LITTLE TIME TO WARM BEFORE
NIGHTFALL...LEADING TO A MORE WIDESPREAD FREEZE. OR...AS THE RUC
SUGGESTS....CLOUDS COULD REMAIN OVER PORTIONS OF THE AREA THROUGH
MUCH OF THE NIGHT...ELIMINATING THE FROST/FREEZE POTENTIAL. AT
THIS POINT HOWEVER...FOLLOWED CLOSER TO NAM/GFS GUIDANCE AND
MAINTAINED CLEARING SKIES BY TONIGHT AND THUS HAVE MADE NO CHANGES
TO CURRENT PRODUCTS.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
DRY SFC HIGH PRES UNDR NW FLOW ALOFT WL MAINTAIN COLD TEMPS
THROUGH THE WEEKEND. EXPECT READINGS OF 10 TO 15 DEGREES UNDR THE
AVERAGES WITH FROST POTENTIAL AGAIN ON SATURDAY NGT.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
SFC HIGH PRES IS EXPECTED TO MAINTAIN DRY WEA UNTIL A WARM FRONT
INCREASES PCPN CHCS FOR WEDNESDAY AND THURSDAY. INITIALLY COLD TEMPS
WL MODERATE TO...AND THEN ABOVE SEASONAL LVLS AS SLY FLOW RESUMES
BY MID WEEK.
&&
.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
GENERAL MVFR TO VFR STRATOCU REMAINS IN PLACE THIS AFTERNOON WITH
KMGW AND KFKL STILL BELOW 2000 FT AT THIS HOUR. CEILINGS WILL SLOWLY
LIFT DURING THE AFTERNOON...WITH GENERAL BROKEN VFR CEILINGS BY
THE LATE AFTERNOON HOURS. WINDS GUSTS OF 15 TO 20 KNOTS WILL PERSIST
THROUGH THE AFTERNOON...BUT SHOULD DIMINISH AFTER SUNSET. STRATOCU
CEILINGS MAY PERSIST AND LOWER INTO TONIGHT WITH NORTHERLY FLOW
OFF THE LAKES INTO SATURDAY MORNING.
.OUTLOOK.../SATURDAY THROUGH TUESDAY/...
HIGH PRESSURE WL MAINTAIN VFR THROUGH EARLY NXT WEEK.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...FREEZE WARNING FROM 3 AM TO 8 AM EDT SATURDAY FOR MDZ001.
OH...FROST ADVISORY FROM 3 AM TO 8 AM EDT SATURDAY FOR OHZ039>041-
048>050-057>059-068-069.
PA...FROST ADVISORY FROM 3 AM TO 8 AM EDT SATURDAY FOR PAZ020-021-
029-031-073-075.
FREEZE WARNING FROM 3 AM TO 8 AM EDT SATURDAY FOR PAZ007>009-
013>016-022-023-074-076.
WV...FROST ADVISORY FROM 3 AM TO 8 AM EDT SATURDAY FOR WVZ001>004-
012-021-022.
FREEZE WARNING FROM 3 AM TO 8 AM EDT SATURDAY FOR WVZ023-041.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1145 AM EDT FRI MAY 24 2013
.SYNOPSIS...
DRY AND COOL WEATHER CAN BE EXPECTED FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
LIGHT SHOWERS/DRIZZLE WILL CONTINUE TO DIMINISH THROUGH THE
AFTERNOON AS DRIER AIR WITH THE APPROACHING HIGH PRESSURE BEGINS
TO BUILD OVERHEAD. THE BIGGEST CONCERN FOR THE NEAR TERM IS THE
IMPACT CLOUD COVER WILL HAVE ON TEMPERATURES TODAY THROUGH THE
OVERNIGHT AND HOW THIS WILL FURTHER IMPACT FROST/FREEZE ACROSS THE
FORECAST AREA. THE MOST RECENT RUNS OF THE HRRR AND RUC SUGGEST THAT
MOISTURE TRAPPED UNDER THE LOW LEVEL INVERSION WILL STRUGGLE TO
MIX OUT TODAY...KEEPING CLOUD COVER OVER MUCH OF THE REGION LONGER
THAN ORIGINALLY ANTICIPATED. HAVE ALREADY LOWERED HIGH
TEMPERATURES A FEW DEGREES TODAY WITH THE CONTINUED COLD ADVECTION
AND CLOUD COVER. DEPENDING ON WHEN THE LOWER LEVELS DRY
OUT...TEMPERATURES MAY HAVE LITTLE TIME TO WARM BEFORE
NIGHTFALL...LEADING TO A MORE WIDESPREAD FREEZE. OR...AS THE RUC
SUGGESTS....CLOUDS COULD REMAIN OVER PORTIONS OF THE AREA THROUGH
MUCH OF THE NIGHT...ELIMINATING THE FROST/FREEZE POTENTIAL. AT
THIS POINT HOWEVER...FOLLOWED CLOSER TO NAM/GFS GUIDANCE AND
MAINTAINED CLEARING SKIES BY TONIGHT AND THUS HAVE MADE NO CHANGES
TO CURRENT PRODUCTS.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
DRY SFC HIGH PRES UNDR NW FLOW ALOFT WL MAINTAIN COLD TEMPS
THROUGH THE WEEKEND. EXPECT READINGS OF 10 TO 15 DEGREES UNDR THE
AVERAGES WITH FROST POTENTIAL AGAIN ON SATURDAY NGT.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
SFC HIGH PRES IS EXPECTED TO MAINTAIN DRY WEA UNTIL A WARM FRONT
INCREASES PCPN CHCS FOR WEDNESDAY AND THURSDAY. INITIALLY COLD TEMPS
WL MODERATE TO...AND THEN ABOVE SEASONAL LVLS AS SLY FLOW RESUMES
BY MID WEEK.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
EARLY MRNG IFR AND MVFR ST AND STRATOCU CEILINGS ARE EXPECTED TO
IMPROVE AS THE DAY PROGRESSES WITH DRY ADVCTN GRADUALLY INCRSG T/DP
SPREADS DESPITE COLD FLOW. WIND GUSTS TO ABOUT 22 KTS CAN BE EXPECTED
IN THE SHALLOW MIXING REGIME. THAT POTENTIAL WL CEASE WITH
DECOUPLING THIS EVE.
.OUTLOOK.../SATURDAY THROUGH TUESDAY/...
HIGH PRESSURE WL MAINTAIN VFR THROUGH EARLY NXT WEEK.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...FREEZE WARNING FROM 3 AM TO 8 AM EDT SATURDAY FOR MDZ001.
OH...FROST ADVISORY FROM 3 AM TO 8 AM EDT SATURDAY FOR OHZ039>041-
048>050-057>059-068-069.
PA...FROST ADVISORY FROM 3 AM TO 8 AM EDT SATURDAY FOR PAZ020-021-
029-031-073-075.
FREEZE WARNING FROM 3 AM TO 8 AM EDT SATURDAY FOR PAZ007>009-
013>016-022-023-074-076.
WV...FROST ADVISORY FROM 3 AM TO 8 AM EDT SATURDAY FOR WVZ001>004-
012-021-022.
FREEZE WARNING FROM 3 AM TO 8 AM EDT SATURDAY FOR WVZ023-041.
&&
$$
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1230 PM EDT FRI MAY 24 2013
.AVIATION...
//DISCUSSION...
12Z DTX SOUNDING SHOWED A REAL STRONG INVERSION AROUND 4000
FEET...WHICH ALLOWED COLD NORTHERLY FLOW OFF LAKE HURON TO SUPPORT
SOLID STRATUS DECK...WHICH IS CURRENTLY IN THE PROCESS OF MIXING
OUT. ONCE THIS OCCURS (MID AFTERNOON)...CLEAR SKIES SHOULD BE
THE RULE INTO TONIGHT. LOW LEVELS SHOULD BE WARM ENOUGH AND FLOW
BACKED TO THE WNW NOT TO SUPPORT A REPEAT PERFORMANCE OF THE LOW
CLOUDS TONIGHT. THERE WILL BE SOME MID/HIGH CLOUDS ARRIVING OVERNIGHT
HOWEVER...WITH JUST A BIT OF DIURNAL CU DEVELOPING TOMORROW (5000
FEET). MARGINALLY GUSTY NORTHWEST WINDS (AROUND 20 KNOTS) EARLY THIS
AFTERNOON DIMINISHING...WITH LIGHT AND VARIABLE WINDS TONIGHT INTO
TOMORROW.
//DTW THRESHOLD THREATS...
* LOW CONFIDENCE IN CEILINGS BELOW 5000 FEET 18-20Z.
&&
.PREV DISCUSSION...ISSUED 340 AM EDT FRI MAY 24 2013
SHORT TERM...TODAY AND TONIGHT
THE WEATHER UP FOR DISCUSSION IS THE PROSPECTS FOR OVERCAST SKIES
TODAY AS AN OPAQUE BLANKET OF 030-035 FT STRATUS IS AGGRESSIVELY
DIVING SOUTHWARD ACROSS LAKE HURON. TRAJECTORY OF CLOUD DECK IN
ADDITION TO THE ORIENTATION OF THE WESTERN EDGE ALIGNS WELL WITH THE
AXIS OF MAXIMUM 925-850MB COLD AIR ADVECTION AND THE DEPRESSION OF
THE LONGWAVE TROUGH AXIS. NWP DATA IS VIRTUALLY VOID OF CLOUD...A
RESULT OF INADEQUATE VERTICAL RESOLUTION WITHIN THE MODELS. WHILE
THE CLOUD IS COMPLETELY OPAQUE IT IS UNDOUBTEDLY A SHALLOW LAYER OF
MOISTURE THAT IS LIKELY TRAPPED WITHIN THE BASE OF THE INVERSION
AT/AROUND 900-890MB. RUC SOUNDINGS SHOW SATURATION AT THIS
ZONE...BUT THE SOUNDING STRUCTURE ITSELF DOES NOT INSPIRE MUCH
CONFIDENCE AS IT IS THE WRONG PROFILE. GIVEN THE TRUE NORTHERLY
TRAJECTORY...HAVE DECIDED TO INTRODUCE OVERCAST CONDITIONS FOR MUCH
OF THE CWA THROUGH THE MORNING HOURS. IT WILL BE DIFFICULT TO
PINPOINT ANY WEST EDGE OF THE CLOUDS GIVEN DEGREE OF DRY AIR
IMMEDIATELY TO THE WEST. PATTERN RECOGNITION SUGGESTS ENTRAINMENT AT
THE EDGE SHOULD AID DIURNAL MIXING TO FORCE STRATUS TO GO BROKEN BY
LATE MORNING...EVENTUALLY CLEARING OUT FOR THE AFTERNOON.
LOWERED MAX TEMPERATURES FOR MANY AREAS DUE TO THE CLOUD AND STEADY
COLD AIR ADVECTION. EXPECT TEMPERATURES TO EVENTUALLY REACH 60-61
DEGREES ACROSS THE SOUTH AND SAGINAW VALLEY VERY LATE IN THE DAY.
OTHERWISE TEMPERATURES ARE GOING TO STRUGGLE TO REACH THE LOWER 50S
IN THE THUMB.
FOR TONIGHT...THE COMPACT VORT OVER NORTHERN MANITOBA WILL GET
SQUEEZED WITH A ROGUE VORTICITY STREAMER OFF OF THE PACNW ANOMALY
MERGING OVER THE WESTERN GREAT LAKES. THIS WILL OCCUR DOWN THE FRONT
EDGE OF THE CENTRAL CONUS RIDGE...ALLOWING FOR A VERY HEALTHY
AGEOSTROPHIC RESPONSE AND STRIPE OF FRONTOGENESIS VERY LATE. ANY
SIGNIFICANT TEMPERATURE GRADIENT WILL RESIDE WELL WEST OF LOWER
MICHIGAN WHICH IS WHERE THE PRECIPITATION RESPONSE WILL OCCUR.
REGARDLESS...INCREASING CLOUDS LATE WILL ESTABLISH A FLOOR ON
MINIMUM TEMPERATURES TONIGHT.
LONG TERM...SATURDAY THROUGH THURSDAY
THE OVERALL PATTERN ACROSS NORTH AMERICA THIS WEEKEND WILL FEATURE A
QUASI OMEGA BLOCK. SHORT WAVE ENERGY NOW SHOWN ROTATING INTO NRN
MANITOBA IS FORECAST TO TRACK ACROSS THE ERN GREAT LAKES AND MID
ATLANTIC EARLY SATURDAY...LEADING TO DEEPENING OF AN UPPER LOW
ROTATING ACROSS NEW ENGLAND. LOWER MI WILL BE LOCATED BETWEEN THIS
SYSTEM AND AMPLIFYING MID LEVEL RIDGING ACROSS THE NRN PLAINS/UPPER
MS VALLEY. THIS WILL PLACE THE FORECAST AREA WITHIN A STRONGLY
CONFLUENT UPPER FLOW WITH PERSISTENT HIGH PRESSURE AT THE SURFACE.
THE RESIDENT AIRMASS ACROSS THE GREAT LAKES WILL BE COOL AND VERY
DRY. TEMPS ON SATURDAY SHOULD ONLY RISE TO THE LOW 60S OVER MUCH OF
THE FORECAST AREA WITH 850MB TEMPS HOVERING AROUND +2C. THE AIRMASS
WILL MODERATE DURING THE COURSE OF THE WEEKEND...WITH HIGHS EXPECTED
TO BE AROUND 70 BY MEMORIAL DAY. GIVEN THE DRY AIRMASS AND LIGHT
WINDS...NIGHTTIME LOWS WILL BE QUITE CHILLY THIS WEEKEND /30S AND
40S/.
A SEASONALLY STRONG 140+ KNOT UPPER JET IS FORECAST DIVE INTO THE
PACIFIC NORTHWEST EARLY NEXT WEEK...LEADING TO LONG WAVE TROUGH
AMPLIFICATION ACROSS THE WRN US AND A BUILDING SUBTROPICAL RIDGE
ACROSS THE SERN US. THIS WILL ALLOW THE MID LEVEL RIDGE TO BECOME
MORE PROGRESSIVE AND PASS EAST OF LOWER MI TOWARD MIDWEEK...ALLOWING
A SFC WARM FRONT TO LIFT ACROSS THE REGION FROM THE SOUTHWEST. THIS
WARM FRONT WILL ADVECT A WARM...MOIST AND UNSTABLE AIRMASS INTO THE
FORECAST AREA. THE GFS CONTINUES TO BRING THIS WARM FRONT THROUGH
FASTER THAN THE OTHER MODEL SOLUTIONS /SUGGESTING CONVECTION AS
EARLY AS MON NIGHT/. THE GFS HAS SOME OBVIOUS CONVECTIVE FEEDBACK
ISSUES DUE TO POTENTIAL MCS DEVELOPMENT OVER THE PLAINS. THE GFS IS
ALSO LESS AMPLIFIED WITH THE LONG WAVE TROUGH OVER THE WRN US. GIVEN
THE STRENGTH OF THE POLAR JET AND POTENTIAL PHASING WITH THE
SUBTROPICAL JET...THE MORE AMPLIFIED ECMWF REMAINS THE PREFERRED
SOLUTION. THIS SUGGESTS THE BETTER CHANCES FOR CONVECTION WILL HOLD
OFF UNTIL THE TUES NIGHT/WED TIME FRAME. DESPITE THIS UNCERTAINTY...
THE OVERALL TREND NEXT WEEK WILL BE FOR WARMER AND MORE HUMID
CONDITIONS WITH INCREASING CHANCES FOR THUNDERSTORMS.
MARINE...
UNSEASONABLE CONDITIONS ARE IN PLACE OVER THE CENTRAL GREAT LAKES
TODAY AS COLD AIR ADVECTION IS ONGOING WITHIN A DEEP TROUGH AXIS.
EFFICIENT NORTHERLY FLOW AND A LONG FETCH OVER THE WATERS WILL
SUSTAIN HIGH WAVE ACTIVITY FROM SAGINAW BAY DOWN TO PORT HURON.
RECENT WATER TEMPERATURE READINGS FROM THE BUOYS SUGGESTS THAT
CONDITIONS WILL BE SOLIDLY IN THE NEUTRAL REGIME OUT OVER THE OPEN
LAKE WHICH IS ATYPICAL FOR LATE MAY. IN FACT...CONDITIONS ARE
UNSTABLE FOR SAGINAW BAY WITH WATER TEMPERATURE READINGS SUGGESTING
LSTS ARE AT AROUND 13 TO 14 C VS AN 850MB TEMPERATURE THAT WILL BE
DIPPING DOWN TO -4C BY 12Z THIS MORNING. WILL EXPAND THE ADVISORY TO
INCLUDE INNER SAGINAW. CONDITIONS ARE MORE MARGINAL ON LAKE ST CLAIR
AND LAKE ERIE. WILL GIVE RESPECT TO PEAK OF THE COLD AIR ADVECTION
THAT WILL OCCUR THIS MORNING FOR THE SOUTHERN ZONES AND EXTEND THE
SMALL CRAFT FOR THEM AS WELL. THE STABLE SURFACE ANTICYCLONE WILL
BUILD INTO THE CENTRAL GREAT LAKES TONIGHT BRINGING A RETURN OF MUCH
MORE FAMILIAR STABLE SEASON MARINE WEATHER.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...
SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT
HURON...UNTIL 8 PM FRIDAY.
SMALL CRAFT ADVISORY...OUTER SAGINAW BAY...UNTIL 6 PM FRIDAY.
LAKE ST CLAIR...
SMALL CRAFT ADVISORY...UNTIL 4 PM FRIDAY.
MI WATERS OF LAKE ERIE...
SMALL CRAFT ADVISORY...UNTIL 4 PM FRIDAY.
&&
$$
AVIATION.....SF
SHORT TERM...CB
LONG TERM....SC
MARINE.......CB
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
702 AM EDT FRI MAY 24 2013
.AVIATION...
//DISCUSSION...
DEEP COLUMN TROUGHING AND COLD AIR ADVECTION HAS TEAMED TOGETHER TO
ALLOW A STRATUS BLANKET TO EXPAND SOUTHWARD INTO THE CENTRAL GREAT
LAKES. A STRAIGHT NORTHERLY WIND TRAJECTORY WILL MAINTAIN THE VERY
AGGRESSIVE MOVEMENT. THE SHALLOW SATURATION MAKES IT EXTREMELY
DIFFICULT FOR THE NWP TO CATCH UP WITH THE TRENDS...WITH THE CLOUD
FORECASTING DISTILLING DOWN TO A NOWCAST OF LATEST SATELLITE
IMAGERY. EXPECT A INCREASING DIABATIC HEATING TERM TO PROMOTE
MIXING AND A OVC TO BKN TREND BY LATE MORNING. REGIONAL RAOBS FROM
LAST EVENING RECORDED THE AMOUNT OF DRY AIR THAT IS NEARBY...SO ONCE
THE DRY AIR BEGINS TO EXERT AN INFLUENCE AT ANY ONE AREA EXPECT A
DECIDED MOVE TO CLEAR AND SUNNY SKIES. IN OTHER WORDS...THERE IS LOW
CONFIDENCE IN TIMING.
AT DTW...LINEAR INTERPOLATION OF EXISTING CLOUD DECK IS SET TO MOVE
INTO THE TERMINAL PRIOR TO THE START OF THE TAF PERIOD. LOW
CONFIDENCE EXISTS IN WHEN TO END THE MVFR CEILINGS...BUT A SAFE
ESTIMATE WILL BE LATE MORNING WITH AN INCREASE IN DAYTIME SURFACE
HEATING.
//DTW THRESHOLD THREATS...
* LOW CONFIDENCE THAT CEILING HEIGHTS OF LESS THAN 5000FT WILL
PLAGUE THE TERMINAL THROUGH THE MORNING HOURS.
&&
.PREV DISCUSSION...ISSUED 340 AM EDT FRI MAY 24 2013
SHORT TERM...TODAY AND TONIGHT
THE WEATHER UP FOR DISCUSSION IS THE PROSPECTS FOR OVERCAST SKIES
TODAY AS AN OPAQUE BLANKET OF 030-035 FT STRATUS IS AGGRESSIVELY
DIVING SOUTHWARD ACROSS LAKE HURON. TRAJECTORY OF CLOUD DECK IN
ADDITION TO THE ORIENTATION OF THE WESTERN EDGE ALIGNS WELL WITH THE
AXIS OF MAXIMUM 925-850MB COLD AIR ADVECTION AND THE DEPRESSION OF
THE LONGWAVE TROUGH AXIS. NWP DATA IS VIRTUALLY VOID OF CLOUD...A
RESULT OF INADEQUATE VERTICAL RESOLUTION WITHIN THE MODELS. WHILE
THE CLOUD IS COMPLETELY OPAQUE IT IS UNDOUBTEDLY A SHALLOW LAYER OF
MOISTURE THAT IS LIKELY TRAPPED WITHIN THE BASE OF THE INVERSION
AT/AROUND 900-890MB. RUC SOUNDINGS SHOW SATURATION AT THIS
ZONE...BUT THE SOUNDING STRUCTURE ITSELF DOES NOT INSPIRE MUCH
CONFIDENCE AS IT IS THE WRONG PROFILE. GIVEN THE TRUE NORTHERLY
TRAJECTORY...HAVE DECIDED TO INTRODUCE OVERCAST CONDITIONS FOR MUCH
OF THE CWA THROUGH THE MORNING HOURS. IT WILL BE DIFFICULT TO
PINPOINT ANY WEST EDGE OF THE CLOUDS GIVEN DEGREE OF DRY AIR
IMMEDIATELY TO THE WEST. PATTERN RECOGNITION SUGGESTS ENTRAINMENT AT
THE EDGE SHOULD AID DIURNAL MIXING TO FORCE STRATUS TO GO BROKEN BY
LATE MORNING...EVENTUALLY CLEARING OUT FOR THE AFTERNOON.
LOWERED MAX TEMPERATURES FOR MANY AREAS DUE TO THE CLOUD AND STEADY
COLD AIR ADVECTION. EXPECT TEMPERATURES TO EVENTUALLY REACH 60-61
DEGREES ACROSS THE SOUTH AND SAGINAW VALLEY VERY LATE IN THE DAY.
OTHERWISE TEMPERATURES ARE GOING TO STRUGGLE TO REACH THE LOWER 50S
IN THE THUMB.
FOR TONIGHT...THE COMPACT VORT OVER NORTHERN MANITOBA WILL GET
SQUEEZED WITH A ROGUE VORTICITY STREAMER OFF OF THE PACNW ANOMALY
MERGING OVER THE WESTERN GREAT LAKES. THIS WILL OCCUR DOWN THE FRONT
EDGE OF THE CENTRAL CONUS RIDGE...ALLOWING FOR A VERY HEALTHY
AGEOSTROPHIC RESPONSE AND STRIPE OF FRONTOGENESIS VERY LATE. ANY
SIGNIFICANT TEMPERATURE GRADIENT WILL RESIDE WELL WEST OF LOWER
MICHIGAN WHICH IS WHERE THE PRECIPITATION RESPONSE WILL OCCUR.
REGARDLESS...INCREASING CLOUDS LATE WILL ESTABLISH A FLOOR ON
MINIMUM TEMPERATURES TONIGHT.
LONG TERM...SATURDAY THROUGH THURSDAY
THE OVERALL PATTERN ACROSS NORTH AMERICA THIS WEEKEND WILL FEATURE A
QUASI OMEGA BLOCK. SHORT WAVE ENERGY NOW SHOWN ROTATING INTO NRN
MANITOBA IS FORECAST TO TRACK ACROSS THE ERN GREAT LAKES AND MID
ATLANTIC EARLY SATURDAY...LEADING TO DEEPENING OF AN UPPER LOW
ROTATING ACROSS NEW ENGLAND. LOWER MI WILL BE LOCATED BETWEEN THIS
SYSTEM AND AMPLIFYING MID LEVEL RIDGING ACROSS THE NRN PLAINS/UPPER
MS VALLEY. THIS WILL PLACE THE FORECAST AREA WITHIN A STRONGLY
CONFLUENT UPPER FLOW WITH PERSISTENT HIGH PRESSURE AT THE SURFACE.
THE RESIDENT AIRMASS ACROSS THE GREAT LAKES WILL BE COOL AND VERY
DRY. TEMPS ON SATURDAY SHOULD ONLY RISE TO THE LOW 60S OVER MUCH OF
THE FORECAST AREA WITH 850MB TEMPS HOVERING AROUND +2C. THE AIRMASS
WILL MODERATE DURING THE COURSE OF THE WEEKEND...WITH HIGHS EXPECTED
TO BE AROUND 70 BY MEMORIAL DAY. GIVEN THE DRY AIRMASS AND LIGHT
WINDS...NIGHTTIME LOWS WILL BE QUITE CHILLY THIS WEEKEND /30S AND
40S/.
A SEASONALLY STRONG 140+ KNOT UPPER JET IS FORECAST DIVE INTO THE
PACIFIC NORTHWEST EARLY NEXT WEEK...LEADING TO LONG WAVE TROUGH
AMPLIFICATION ACROSS THE WRN US AND A BUILDING SUBTROPICAL RIDGE
ACROSS THE SERN US. THIS WILL ALLOW THE MID LEVEL RIDGE TO BECOME
MORE PROGRESSIVE AND PASS EAST OF LOWER MI TOWARD MIDWEEK...ALLOWING
A SFC WARM FRONT TO LIFT ACROSS THE REGION FROM THE SOUTHWEST. THIS
WARM FRONT WILL ADVECT A WARM...MOIST AND UNSTABLE AIRMASS INTO THE
FORECAST AREA. THE GFS CONTINUES TO BRING THIS WARM FRONT THROUGH
FASTER THAN THE OTHER MODEL SOLUTIONS /SUGGESTING CONVECTION AS
EARLY AS MON NIGHT/. THE GFS HAS SOME OBVIOUS CONVECTIVE FEEDBACK
ISSUES DUE TO POTENTIAL MCS DEVELOPMENT OVER THE PLAINS. THE GFS IS
ALSO LESS AMPLIFIED WITH THE LONG WAVE TROUGH OVER THE WRN US. GIVEN
THE STRENGTH OF THE POLAR JET AND POTENTIAL PHASING WITH THE
SUBTROPICAL JET...THE MORE AMPLIFIED ECMWF REMAINS THE PREFERRED
SOLUTION. THIS SUGGESTS THE BETTER CHANCES FOR CONVECTION WILL HOLD
OFF UNTIL THE TUES NIGHT/WED TIME FRAME. DESPITE THIS UNCERTAINTY...
THE OVERALL TREND NEXT WEEK WILL BE FOR WARMER AND MORE HUMID
CONDITIONS WITH INCREASING CHANCES FOR THUNDERSTORMS.
MARINE...
UNSEASONABLE CONDITIONS ARE IN PLACE OVER THE CENTRAL GREAT LAKES
TODAY AS COLD AIR ADVECTION IS ONGOING WITHIN A DEEP TROUGH AXIS.
EFFICIENT NORTHERLY FLOW AND A LONG FETCH OVER THE WATERS WILL
SUSTAIN HIGH WAVE ACTIVITY FROM SAGINAW BAY DOWN TO PORT HURON.
RECENT WATER TEMPERATURE READINGS FROM THE BUOYS SUGGESTS THAT
CONDITIONS WILL BE SOLIDLY IN THE NEUTRAL REGIME OUT OVER THE OPEN
LAKE WHICH IS ATYPICAL FOR LATE MAY. IN FACT...CONDITIONS ARE
UNSTABLE FOR SAGINAW BAY WITH WATER TEMPERATURE READINGS SUGGESTING
LSTS ARE AT AROUND 13 TO 14 C VS AN 850MB TEMPERATURE THAT WILL BE
DIPPING DOWN TO -4C BY 12Z THIS MORNING. WILL EXPAND THE ADVISORY TO
INCLUDE INNER SAGINAW. CONDITIONS ARE MORE MARGINAL ON LAKE ST CLAIR
AND LAKE ERIE. WILL GIVE RESPECT TO PEAK OF THE COLD AIR ADVECTION
THAT WILL OCCUR THIS MORNING FOR THE SOUTHERN ZONES AND EXTEND THE
SMALL CRAFT FOR THEM AS WELL. THE STABLE SURFACE ANTICYCLONE WILL
BUILD INTO THE CENTRAL GREAT LAKES TONIGHT BRINGING A RETURN OF MUCH
MORE FAMILIAR STABLE SEASON MARINE WEATHER.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...
SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT
HURON...UNTIL 8 PM FRIDAY.
SMALL CRAFT ADVISORY...OUTER SAGINAW BAY...UNTIL 6 PM FRIDAY.
SMALL CRAFT ADVISORY...INNER SAGINAW BAY...UNTIL 10 AM FRIDAY.
LAKE ST CLAIR...
SMALL CRAFT ADVISORY...UNTIL 4 PM FRIDAY.
MI WATERS OF LAKE ERIE...
SMALL CRAFT ADVISORY...UNTIL 4 PM FRIDAY.
&&
$$
AVIATION.....99
SHORT TERM...CB
LONG TERM....SC
MARINE.......CB
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
340 AM EDT FRI MAY 24 2013
.SHORT TERM...TODAY AND TONIGHT
THE WEATHER UP FOR DISCUSSION IS THE PROSPECTS FOR OVERCAST SKIES
TODAY AS AN OPAQUE BLANKET OF 030-035 FT STRATUS IS AGGRESSIVELY
DIVING SOUTHWARD ACROSS LAKE HURON. TRAJECTORY OF CLOUD DECK IN
ADDITION TO THE ORIENTATION OF THE WESTERN EDGE ALIGNS WELL WITH THE
AXIS OF MAXIMUM 925-850MB COLD AIR ADVECTION AND THE DEPRESSION OF
THE LONGWAVE TROUGH AXIS. NWP DATA IS VIRTUALLY VOID OF CLOUD...A
RESULT OF INADEQUATE VERTICAL RESOLUTION WITHIN THE MODELS. WHILE
THE CLOUD IS COMPLETELY OPAQUE IT IS UNDOUBTEDLY A SHALLOW LAYER OF
MOISTURE THAT IS LIKELY TRAPPED WITHIN THE BASE OF THE INVERSION
AT/AROUND 900-890MB. RUC SOUNDINGS SHOW SATURATION AT THIS
ZONE...BUT THE SOUNDING STRUCTURE ITSELF DOES NOT INSPIRE MUCH
CONFIDENCE AS IT IS THE WRONG PROFILE. GIVEN THE TRUE NORTHERLY
TRAJECTORY...HAVE DECIDED TO INTRODUCE OVERCAST CONDITIONS FOR MUCH
OF THE CWA THROUGH THE MORNING HOURS. IT WILL BE DIFFICULT TO
PINPOINT ANY WEST EDGE OF THE CLOUDS GIVEN DEGREE OF DRY AIR
IMMEDIATELY TO THE WEST. PATTERN RECOGNITION SUGGESTS ENTRAINMENT AT
THE EDGE SHOULD AID DIURNAL MIXING TO FORCE STRATUS TO GO BROKEN BY
LATE MORNING...EVENTUALLY CLEARING OUT FOR THE AFTERNOON.
LOWERED MAX TEMPERATURES FOR MANY AREAS DUE TO THE CLOUD AND STEADY
COLD AIR ADVECTION. EXPECT TEMPERATURES TO EVENTUALLY REACH 60-61
DEGREES ACROSS THE SOUTH AND SAGINAW VALLEY VERY LATE IN THE DAY.
OTHERWISE TEMPERATURES ARE GOING TO STRUGGLE TO REACH THE LOWER 50S
IN THE THUMB.
FOR TONIGHT...THE COMPACT VORT OVER NORTHERN MANITOBA WILL GET
SQUEEZED WITH A ROGUE VORTICITY STREAMER OFF OF THE PACNW ANOMALY
MERGING OVER THE WESTERN GREAT LAKES. THIS WILL OCCUR DOWN THE FRONT
EDGE OF THE CENTRAL CONUS RIDGE...ALLOWING FOR A VERY HEALTHY
AGEOSTROPHIC RESPONSE AND STRIPE OF FRONTOGENESIS VERY LATE. ANY
SIGNIFICANT TEMPERATURE GRADIENT WILL RESIDE WELL WEST OF LOWER
MICHIGAN WHICH IS WHERE THE PRECIPITATION RESPONSE WILL OCCUR.
REGARDLESS...INCREASING CLOUDS LATE WILL ESTABLISH A FLOOR ON
MINIMUM TEMPERATURES TONIGHT.
&&
.LONG TERM...SATURDAY THROUGH THURSDAY
THE OVERALL PATTERN ACROSS NORTH AMERICA THIS WEEKEND WILL FEATURE A
QUASI OMEGA BLOCK. SHORT WAVE ENERGY NOW SHOWN ROTATING INTO NRN
MANITOBA IS FORECAST TO TRACK ACROSS THE ERN GREAT LAKES AND MID
ATLANTIC EARLY SATURDAY...LEADING TO DEEPENING OF AN UPPER LOW
ROTATING ACROSS NEW ENGLAND. LOWER MI WILL BE LOCATED BETWEEN THIS
SYSTEM AND AMPLIFYING MID LEVEL RIDGING ACROSS THE NRN PLAINS/UPPER
MS VALLEY. THIS WILL PLACE THE FORECAST AREA WITHIN A STRONGLY
CONFLUENT UPPER FLOW WITH PERSISTENT HIGH PRESSURE AT THE SURFACE.
THE RESIDENT AIRMASS ACROSS THE GREAT LAKES WILL BE COOL AND VERY
DRY. TEMPS ON SATURDAY SHOULD ONLY RISE TO THE LOW 60S OVER MUCH OF
THE FORECAST AREA WITH 850MB TEMPS HOVERING AROUND +2C. THE AIRMASS
WILL MODERATE DURING THE COURSE OF THE WEEKEND...WITH HIGHS EXPECTED
TO BE AROUND 70 BY MEMORIAL DAY. GIVEN THE DRY AIRMASS AND LIGHT
WINDS...NIGHTTIME LOWS WILL BE QUITE CHILLY THIS WEEKEND /30S AND
40S/.
A SEASONALLY STRONG 140+ KNOT UPPER JET IS FORECAST DIVE INTO THE
PACIFIC NORTHWEST EARLY NEXT WEEK...LEADING TO LONG WAVE TROUGH
AMPLIFICATION ACROSS THE WRN US AND A BUILDING SUBTROPICAL RIDGE
ACROSS THE SERN US. THIS WILL ALLOW THE MID LEVEL RIDGE TO BECOME
MORE PROGRESSIVE AND PASS EAST OF LOWER MI TOWARD MIDWEEK...ALLOWING
A SFC WARM FRONT TO LIFT ACROSS THE REGION FROM THE SOUTHWEST. THIS
WARM FRONT WILL ADVECT A WARM...MOIST AND UNSTABLE AIRMASS INTO THE
FORECAST AREA. THE GFS CONTINUES TO BRING THIS WARM FRONT THROUGH
FASTER THAN THE OTHER MODEL SOLUTIONS /SUGGESTING CONVECTION AS
EARLY AS MON NIGHT/. THE GFS HAS SOME OBVIOUS CONVECTIVE FEEDBACK
ISSUES DUE TO POTENTIAL MCS DEVELOPMENT OVER THE PLAINS. THE GFS IS
ALSO LESS AMPLIFIED WITH THE LONG WAVE TROUGH OVER THE WRN US. GIVEN
THE STRENGTH OF THE POLAR JET AND POTENTIAL PHASING WITH THE
SUBTROPICAL JET...THE MORE AMPLIFIED ECMWF REMAINS THE PREFERRED
SOLUTION. THIS SUGGESTS THE BETTER CHANCES FOR CONVECTION WILL HOLD
OFF UNTIL THE TUES NIGHT/WED TIME FRAME. DESPITE THIS UNCERTAINTY...
THE OVERALL TREND NEXT WEEK WILL BE FOR WARMER AND MORE HUMID
CONDITIONS WITH INCREASING CHANCES FOR THUNDERSTORMS.
&&
.MARINE...
UNSEASONABLE CONDITIONS ARE IN PLACE OVER THE CENTRAL GREAT LAKES
TODAY AS COLD AIR ADVECTION IS ONGOING WITHIN A DEEP TROUGH AXIS.
EFFICIENT NORTHERLY FLOW AND A LONG FETCH OVER THE WATERS WILL
SUSTAIN HIGH WAVE ACTIVITY FROM SAGINAW BAY DOWN TO PORT HURON.
RECENT WATER TEMPERATURE READINGS FROM THE BUOYS SUGGESTS THAT
CONDITIONS WILL BE SOLIDLY IN THE NEUTRAL REGIME OUT OVER THE OPEN
LAKE WHICH IS ATYPICAL FOR LATE MAY. IN FACT...CONDITIONS ARE
UNSTABLE FOR SAGINAW BAY WITH WATER TEMPERATURE READINGS SUGGESTING
LSTS ARE AT AROUND 13 TO 14 C VS AN 850MB TEMPERATURE THAT WILL BE
DIPPING DOWN TO -4C BY 12Z THIS MORNING. WILL EXPAND THE ADVISORY TO
INCLUDE INNER SAGINAW. CONDITIONS ARE MORE MARGINAL ON LAKE ST CLAIR
AND LAKE ERIE. WILL GIVE RESPECT TO PEAK OF THE COLD AIR ADVECTION
THAT WILL OCCUR THIS MORNING FOR THE SOUTHERN ZONES AND EXTEND THE
SMALL CRAFT FOR THEM AS WELL. THE STABLE SURFACE ANTICYCLONE WILL
BUILD INTO THE CENTRAL GREAT LAKES TONIGHT BRINGING A RETURN OF MUCH
MORE FAMILIAR STABLE SEASON MARINE WEATHER.
&&
.AVIATION...ISSUED 1146 PM EDT THU MAY 23 2013
//DISCUSSION...
WHAT REMAINS OF LOW VFR TO HIGH MVFR BOUNDARY LAYER CLOUDS WILL WORK
THEIR WAY THROUGH THE AREA WITHIN THE NEXT COUPLE OF HOURS. ONCE
THAT OCCURS, CLEAR SKIES BELOW 10KFT WILL PREVAIL FOR THE BALANCE
OF THE FORECAST PERIOD AS HIGH PRESSURE DOMINATES. DIURNAL HEATING
WILL ALLOW NORTHERLY WINDS TO GUST TO AROUND 20 KTS DURING PEAK
HEATING ON FRIDAY.
//DTW THRESHOLD THREATS...
* NONE
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...
SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT
HURON INCLUDING OUTER SAGINAW BAY...UNTIL 6 PM FRIDAY.
LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.
&&
$$
SHORT TERM...CB
LONG TERM....SC
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 DULUTH MN
640 PM CDT SAT MAY 25 2013
.AVIATION...00Z TAFS
VFR CONDITIONS COVERED THE NORTHLAND. A FEW LIGHT SHOWERS WERE
OCCURRING...WITH RADAR PICKING UP ON SOME RETURNS JUST WEST OF
KDLH. THESE SHOWERS WERE QUICKLY DIMINISHING AND SHOULD BE GONE IN
AN HOUR.
WE KEPT THE TAFS VFR THROUGH THE PERIOD WITH THE MAIN BAROCLINIC
ZONE SOUTH AND WEST OF THE NORTHLAND. THE NAM DOES SUGGEST SOME
MVFR CEILINGS MAY MOVE INTO KBRD AROUND 12Z CONTINUING INTO EARLY
SUNDAY AFTERNOON. HOWEVER...THE RAP KEPT THE LOW LEVEL MOISTURE
WEST AND SOUTH OF THERE...AND WE FOLLOWED THAT TREND AS WELL.
&&
.PREV DISCUSSION... /ISSUED 326 PM CDT SAT MAY 25 2013/
SHORT TERM...BUILDING RIDGE ALOFT CONTINUES TO ALLOW THINNING OF
MID LVL CLOUD MASS ACROSS THE REGION THIS AFTERNOON. SOME CU HAVE
ALSO DEVELOPED AS A RESULT OF DIURNAL WARMING OF BDRY LAYER. TEMPS
LINGER IN THE 40S NEAR LAKE SUPERIOR WITH MID TO UPPER 50S COMMON
INLAND.
TONIGHT/SUNDAY...FAIRLY BENIGN PATTERN THIS PERIOD AS SFC/MID LVL
RIDGING CONTINUES TO PREVAIL ACROSS THE NORTHLAND. MAIN CHANGE TO
PREVIOUS FCST WAS TO SLOW THE ARRIVAL TIME OF THE NEXT AREA OF
CLOUDS AND PRECIP UNTIL SUNDAY EVENING. RAISED MAX TEMPS A
LITTLE SUNDAY WITH MORE SUNSHINE EXPECTED.
LONG TERM...SUNDAY NIGHT THROUGH SATURDAY.
THE EXTENDED PERIOD IS SHAPING UP TO BE A QUITE UNSTABLE AND
POTENTIALLY VERY WET PERIOD...AS THE UPPER LEVEL PATTERN EVOLVES
FROM A DRY SURFACE HIGH DOMINATED PATTERN TO A MEAN TROUGH/SW FLOW
PATTERN. THE SURFACE HIGH AND UPPER LEVEL RIDGE WILL STILL BE
BATTLING THE ADVANCING MOISTURE SUNDAY NIGHT AND INTO MONDAY...WITH
DRY AIR TO THE EAST WITH EASTERLY WINDS...AND A MOIST S/SW FLOW
DEVELOPING IN THE PLAINS. THIS IS SHAPING UP TO BE A NOTORIOUSLY
TRICKY SET UP...WITH THE POTENTIAL FOR MCS DEVELOPMENT. THE
COMPLEXITY OF FRONTAL BOUNDARIES...TRACKING VARIOUS UPPER LEVEL
IMPULSES THAT WILL EJECT OUT OF THE MAIN TROUGH IN THE WESTERN
STATES...AND OUTFLOW BOUNDARY DEVELOPMENT MEANS THAT WE WILL NEED TO
GO WITH FAIRLY HIGH POPS FOR A MAJORITY OF THE REMAINDER OF THE
EXTENDED TIME PERIOD...WITH THE PRECIPITATION TENDING TO FAVOR THE
SOUTH AND EASTERN PORTIONS OF THE CWA. THIS WET PATTERN WILL HOLD
FOR THE ENTIRE EXTENDED TIME FRAME ONCE IT DEVELOPS AS AN UPPER
LEVEL LOW MOVES INTO THE PLAINS ALONG WITH INCREASING GULF MOISTURE.
TEMPS WILL LARGELY BE IN THE 60S AND 70S...BUT IT WILL BE COOLER
NEAR LAKE SUPERIOR FOR MUCH OF THE TIME.
&&
.POINT TEMPS/POPS...
DLH 40 62 44 61 / 20 0 10 30
INL 42 69 44 68 / 10 0 20 40
BRD 44 63 50 68 / 10 10 30 50
HYR 38 69 46 68 / 10 10 10 40
ASX 37 63 43 64 / 10 0 0 30
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...NONE.
&&
$$
SHORT TERM...CANNON
LONG TERM....DAP
AVIATION...MELDE
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1248 AM CDT FRI MAY 24 2013
.UPDATE...
06Z AVIATION DISCUSSION ADDED BELOW.
&&
.SHORT TERM...THROUGH MONDAY
ISSUED AT 204 PM CDT THU MAY 23 2013
23.12Z RAOBS SHOW GOOD 925-850MB COLD ADVECTION ACROSS THE WRN GREAT
LAKES THIS MORNING IN MODERATE NORTHEAST FLOW. FRONTAL SLOPE OVER
THE STATE IS SOMETHING THAT WILL COME INTO PLAY FOR UPCOMING
FORECAST AND HOW FAR IT SLIDES SOUTHWEST. AT 12Z KINL-KABR HAD A 7C
TEMPERATURE DIFFERENCE AT 850MB /12C AT 925MB/. A MASSIVE DRYING
ACROSS MN OCCURRED OVERNIGHT WITH PRECIPITATELY WATER VALUES
PLUMMETING FROM 0.90 TO 0.32 INCHES...OR 136 TO 48 PERCENT NORMAL.
THE SURFACE RIDGE NOSING IN IS QUITE DRY WITH PRECIPITABLE WATER
VALUES IN THE 30 PERCENT RANGE ACROSS SRN CANADA. THIS GAVE WAY TO A
SUNNY BUT COOL DAY TODAY. A HIGHER AMPLITUDE RIDGE AXIS IS
ANCHORED IN THE DAKOTAS AND SOUTH...WHILE A DEEPER CYCLONE HAS NOW
SHIFTED ONSHORE INTO THE NWRN U.S. NUMEROUS SPOKES OF ENERGY ARE
CIRCULATING AROUND THAT LOW...ONE OF WHICH IS QUITE STRONG OVER
NEVADA WITH RAP ANALYSIS SHOWING A TROPOPAUSE FOLD TO NEAR
500MB...ON THE POLEWARD SIDE OF A MEASURED 100KT 250MB JET CORE
NOSE. THIS IS DRIVING HEIGHT FALLS ACROSS MT/ID/UT. SURFACE DEW
POINTS OF MEANING FOR CONVECTION ARE LOCATED IN OKLAHOMA...SOON TO
RETURN NORTHWARD.
FORECAST IS ON TRACK FOR CALMING WINDS TONIGHT AND CLEAR SKIES.
WIDESPREAD FROST SHOULD OCCUR WITH LOWER 30S FORECAST ACROSS NWRN
WI. WITH LOWER DEW POINTS OVER NWRN WI COUNTIES CURRENTLY...HAVE
DECIDED TO JUST ADD ALL OF THOSE COUNTIES INTO THE FROST ADVISORY.
BIG PICTURE DURING THIS PERIOD IS FALLING HEIGHTS AND PRESSURE IN
THE FRONT RANGE WITH SOUTHERLY FLOW INCREASING AND A RETURN OF
MOISTURE TO NEB/SD FRIDAY NIGHT. THIS WILL PLACE THE LOW-LEVEL
THERMAL BOUNDARY ACROSS THE FORECAST AREA FROM 850-925MB...SLIGHTLY
DISPLACED SWWRD...FROM KABR-KMLI. THE CONSENSUS NCEP MODELS AT
23.12Z REMAIN CONSISTENT WITH THEIR PREVIOUS RUNS ON THE FRONTAL
BOUNDARY BECOMING ACTIVE IN THE DAKOTAS/NEB FRIDAY EVENING AND
SHIFTING EAST INTO MN/IA OVERNIGHT. THE 23.00Z ECMWF/UKMET
SOLUTIONS DO AS WELL...HOWEVER THEY REMAIN FURTHER WEST.
THE 300/305K SURFACE IN THE NCEP SOLUTIONS REMAINS CONSISTENT WITH
AN 8G/KG MOISTURE SURGE ISENTROPICALLY LIFTING AND CONVERGING INTO
CENTRAL AND ERN MN FRIDAY OVERNIGHT WITH A FETCH OF ABOUT 500 J/KG
OF MUCAPE FEEDING IT. THE NAM SEEMS TO BE THE MOST AGRESSIVE. NOT
OVERLY IMPRESSIVE FOR SEVERE WEATHER...BUT RATHER THERE IS ENOUGH
FORCING TO GENERATE RA/TSRA SWWRD OF MSP. THE ECMWF SOLUTIONS
SUGGEST MORE OF A FOCUS IN SRN/SWRN MN. THE MAIN QUESTION IS HOW
FAR EAST DOES THIS CONVECTIVE COMPLEX TRACK FRIDAY NIGHT AND HOW FAR
EAST DOES THE FRONTAL BOUNDARY LIFT. HAVE INCREASED RAIN CHANCES
FURTHER EAST FOR FRIDAY NIGHT AND SATURDAY...HOWEVER WITH THE
VERIFICATION RECORD OF THE ECMWF...THERE IS STILL A CHANCE THE
EASTERN AREAS WILL BE DRY. CONFIDENCE IS LOW ON THE EXACT
LOCATION OF THE WEATHER...BUT HIGHER THAT IT WILL BE AN ACTIVE
FRONTAL ZONE WITH SHRA/ISO TSRA.
THIS QUESTION REMAINS THROUGH MONDAY...HOW FAR EAST WILL THE
FRONTAL BAND BE LOCATED. THE FRONT WILL LIKELY REMAIN ACTIVE WITH
SHOWERS/STORMS AND CLOUDS...AND HIGHS QUITE A BIT COOLER THAN OUTSIDE
THE BAND. OVERALL...HAVE INCREASED RAIN CHANCES IN THE WRN/SRN
FORECAST AREA AND TRIED TO REMAIN NEARLY DRY IN THE EAST. SEEMS
LIKE IT WILL BE A CLOUDY WEEKEND...AND THUS HAVE LOWERED HIGHS
SUNDAY AND MONDAY AS WELL. SEVERE WEATHER THREATS ARE MOST
POSSIBLE IN SWRN MN CLOSER TO THE CAPE POOL...AND MONDAY LOOKS
MOST FAVORABLE SHOULD THE INSTABILITY INCREASE AS THE WARM FRONT
MOVES TOWARD MN. HOWEVER...ACTIVITY ALONG THAT FRONT THIS WEEKEND
MAY HAVE MUCH TO DO WITH HOW THE ENVIRONMENT/FRONT EVOLVES MONDAY.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 241 PM CDT THU MAY 23 2013
IT CONTINUES TO LOOK LIKE WE/LL UNFORTUNATELY NEED TO KEEP A
PROLONGED PERIOD OF CHANCE POPS IN THE FORECAST THROUGH THE WEEK
AS THE BAROCLINIC ZONE LINGERS IN THE AREA... WITH ELEVATED
INSTABILITY AND PERSISTENT WARM ADVECTION WORK TO GENERATE
SCATTERED SHRA/TSRA. THERE WILL UNDOUBTEDLY BE SOME DRY PERIODS...
WITH PCPN FOCUSED WHEN INDIVIDUAL SHORTWAVES RIPPLE SOUTHEAST
THROUGH THE UPPER FLOW... BUT AT THIS POINT IT IS IMPOSSIBLE TO
TRY AND PIN POINT WHEN SUCH DRY PERIODS MIGHT OCCUR. THE 12Z ECMWF
HAS COME AROUND MORE IN LINE WITH THE GFS IN KEEPING THINGS MORE
ACTIVE IN OUR AREA THROUGHOUT THE TIME PERIOD... ALTHOUGH BOTH
SUGGEST WE SHOULD FINALLY BRING THE UPPER TROUGH EAST TOWARD THE
REGION BY THE END OF THE WEEK. DEPENDING ON HOW THAT UNFOLDS... WE
COULD HAVE A POSSIBILITY FOR FOCUSED CONVECTION AND POSSIBLE
SEVERE WEATHER DURING THE THURSDAY-FRIDAY TIME FRAME. BUT... UNTIL
THAT POINT THE MAIN ISSUES WOULD LIKELY BE LOCALLY HEAVY RAIN AND
PERHAPS SOME HAIL. IN GENERAL... TEMPERATURES WILL WARM THROUGH
THE WEEK AS THE BONAFIDE WARM SECTOR SLOWLY LIFTS NORTH INTO THE
AREA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT)
ISSUED AT 1248 AM CDT FRI MAY 24 2013
HIGH PRESSURE SLIDING INTO WI TONIGHT WILL PROVIDE EXCELLENT
CONDITIONS THROUGH MUCH OF THE DAY FRIDAY...BUT GOING THROUGH THE
DAY...WILL START TO SEE AN AREA OF SHRA/TSRA MOVE EAST THROUGH
THE DAKOTAS. BASED ON MPX SOUNDING LAST NIGHT...AIRMASS OVER THE
MPX AIRSPACE IS VERY DRY...WHICH SHOULD DELAY THE ONSET OF ANY
PRECIP. DID NOT INTRODUCE ANY VCSH UNTIL AFTER 00Z...BUT QUICKLY
SPREAD IT EAST ACROSS MN AS THE LLJ BEGINS NOSING INTO IOWA THIS
EVENING. GIVEN DRY ANTECEDENT CONDITIONS...KEPT CONDS VFR AS IT
WILL TAKE A WHILE TO MOISTEN THE LOW LEVELS...BUT BY 12Z
SATURDAY...PROBABILITIES FOR MVFR OR LOWER CIGS WILL BE INCREASING
PRECIPITOUSLY ACROSS MN. FOR WINDS...HIGH PRESSURE WILL BE SLIDING
OVER TOWARD MICH OVER THE DAY...WITH GRADIENT INCREASING AS A
RESULT. WINDS WILL BE STRONGEST WEST...WEAKEST EAST. BASED ON
SOUNDINGS...EXPECT SOME STRONG SUSTAINED WINDS...WITH MINIMAL
GUSTING. A 16G21KT TYPE DAY LOOKS TO AHEAD FOR WRN MN.
KMSP...CONFIDENCE HIGH IN TAF PARAMETERS UNTIL THE TAIL END OF THE
TAF. AT THIS POINT...KEPT ONLY A VCSH MENTION...THOUGH AT SOME
POINT LATE FRIDAY NIGHT...DO EXPECT THERE TO BE A PERIOD OF
SHRA/ISO TSRA. THIS WOULD BE MOST LIKELY BETWEEN 8Z AND 12Z. AS
FOR CIGS...KEPT THEM VFR...THOUGH CHANCE FOR MVFR...INCLUDING SUB
017 CIGS INCREASES AFTER 8Z SAT.
/OUTLOOK FOR KMSP/
SAT...CHC MVFR OR LOWER CIGS. CHC SHRA/TSRA. WINDS SE 10-15 KTS.
SUN...CHC MVFR OR LOWER CIGS. CHC SHRA/TSRA. WINDS SE 10-15 KTS.
MON...CHC MVFR OR LOWER CIGS. CHC SHRA/TSRA. WINDS SE 10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...FROST ADVISORY UNTIL 7 AM CDT THIS MORNING FOR MNZ045-052-053-
063.
WI...FROST ADVISORY UNTIL 7 AM CDT THIS MORNING FOR WIZ014>016-
023>028.
&&
$$
SHORT TERM...BAUMGARDT/ARX
LONG TERM...
AVIATION...MPG
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
950 PM CDT Sat May 25 2013
.UPDATE...
Issued at 950 PM CDT SAT MAY 25 2013
With convection struggling to develop along the frontal boundary
across far northern Missouri this evening, have opted to reduce the
chance of precipitation significantly over the next few hours. Some
development along an elevated boundary stretching from southeast
through central Iowa will be possible over the next few hours and
could build southwest into the forecast area, so have preserved
increased PoPs across our far northeast during the early morning
hours. Convection currently over north central Kansas may also push
eastward into the area after 09z, so have brought in slightly higher
chances for showers and thunderstorms in the northwest during this
period.
&&
.SHORT TERM...(This Evening through Sunday)
Issued at 345 PM CDT SAT MAY 25 2013
Very few changes were needed to the forecast through tomorrow. Based
on latest high res models, radar, and satellite trends it appears,
other than a stray shower across the MO/IA border, the CWA should
remain dry this evening. Later tonight a small cluster of storms is
progged to work in from the west, but the latest HRRR depicts a
weaker system than what much of the NRN third of the CWA experienced
early this morning. At this time I have an overnight precip forecast
that favors the northern half of the CWA with higher chance pops
compared to lower chances to the south. As for tomorrow, more of
the same with lingering scattered morning showers and weak
thunderstorms with perhaps redevelopment in the afternoon.
Temperature wise the CWA will remain mild and rather muggy as
compared to the past several days under partly to mostly cloudy
skies.
.LONG TERM...(Sunday Night through Saturday)
Issued at 345 PM CDT SAT MAY 25 2013
The potential for wet weather looks to bracket either end of the
work week, though there will be plenty of dry days in between.
Shortwave ridge will be dominating the Central Plains as Memorial
Day dawns, with nocturnal thunderstorm activity likely lingering
through the morning hours. In general, operational and ensemble
models continue to advertise that this modest ridge will stay in
place across the Plains States through Tuesday, when the west CONUS
trough will finally begin to shift east. As the trough begins to
move into the Plains the storm track will shift farther north which
should give most locations in our forecast areas a break from the
rain chances. However, given the negative tilt to the trough as it
shifts into the Plains, and the general synoptic pattern, thoughts
are that storms will not only return tot he forecast, but severe
weather may plague the region by the end of the work week.
Currently, the best potential for storms looks to be Thursday night
and Friday night as the nocturnal jet cranks up ahead of the west
CONUS trough.
Otherwise, with the prevailing storm track, and by extension the
prevailing westerlies, remaining to the north of Kansas and Missouri
through the work week we expect temperatures to rise to a category
or two above normal through the week.
&&
.AVIATION...(For the 00Z TAFS through 00Z Sunday Evening)
Issued at 603 PM CDT SAT MAY 25 2013
Convection has blossomed across western Kansas however models seem to
be evaporating this convection as it moves eastward tonight. With
temperature/dewpoint spreads of 15-20 degrees across the area, that
seems reasonable so have left TAFs dry overnight. It appears better chance for
convection may come tomorrow afternoon but no confidence in timing or
placement to include in the TAF at the moment. GFS MOS/LAMP as well
as NAM BUFR soundings are hinting at MVFR cigs tomorrow morning but
continue to think boundary layer is too moist so have held off on
inclusion in the TAF. Winds will be out of the south between 10-15kts
through tomorrow afternoon when they will become gusty around
20-25kts.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
UPDATE...Laflin
SHORT TERM...Pietrycha
LONG TERM...Cutter
AVIATION...73
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
617 PM CDT SAT MAY 25 2013
.AVIATION...
00Z TAFS FOR KOMA...KLNK AND KOFK.
FORECAST IN REGARDS TO TSRA IS NOT CLEAR. MODELS HAVE DIFFERING
SOLUTIONS WITH COVERAGE AND DEVELOPMENT. FELT CHANCES WERE LOW
ENOUGH TO LEAVE TSRA OUT OF FORECAST PRIOR TO 09Z. BUT WILL KEEP
A CLOSE EYE ON THAT AND AMEND AS NEEDED. ACTIVITY OVER THE HIGH
PLAINS WILL TRY TO TRACK EAST LATER TONIGHT.
OVERALL EXPECT CEILINGS TO LOWER OVERNIGHT INTO THE MVFR CATEGORY
AND POSSIBLY TO IFR. IFR CONDITIONS WOULD BE MOST LIKELY 09Z-14Z.
LIKE TODAY...CEILINGS SHOULD TEND TO IMPROVE TOWARD VFR BY LATE
MORNING OR EARLY AFTERNOON.
MILLER
&&
.PREV DISCUSSION... /ISSUED 311 PM CDT SAT MAY 25 2013/
DISCUSSION...
ALTHOUGH TIMING OF HIGHEST CONCENTRATION OF ANY CONVECTION IS THE
MAIN CHALLENGE FOR ANY GIVEN PERIOD WELL INTO NEXT WEEK...PATTERN
LOOKS TO REMAIN ACTIVE WITH PRECIP CHANCES GOOD IF NOT LIKELY MOST
AREAS MOST EVENINGS/OVERNIGHT PDS.
AT 19Z SURFACE BOUNDARY EXTENDED FROM JUST N OF FNB TO JUST SW OF
OLU/BVN WITH RESIDUAL COOL OUTFLOW FROM MORNING CONVECTION
REINFORCING FRONT. CONVERGENCE NEAR BOUNDARY HAD INCREASED CU
FIELD WCNTRL ZONES AND LATEST RAP MESO ANALYSIS PLACED AXIS OF
2000-3000 J/KG ML CAPE ACROSS THAT AREA WITH LITTLE/NO CIN. SO
THERE REMAINS SOME POSSIBILITY OF CONVECTION DEVELOPING NEAR/N OF
THIS BOUNDARY EARLY THIS EVENING...ESPECIALLY AS ANY SUBSIDENCE
EFFECTS OF DEPARTING MCV FROM EARLIER CONVECTION GETS FARTHER
REMOVED. LATER THIS EVENING/OVERNIGHT HIGH PLAINS CONVECTION WILL
PROBABLY MAKE A RUN TOWARD/INTO FA...POSSIBLY CONSOLIDATING MORE
ACROSS NRN ZONES AIDED BY RR ENTRANCE REGION OF WEAK UPPER JET
SEGMENT. HOWEVER...CAN/T RULE OUT ACTIVITY FARTHER S AS WELL SINCE
BOUNDARY MAY NOT MOVE MUCH TONIGHT. LOW LEVEL JET DOES STRENGTHEN
SOME INTO FRONT OVERNIGHT...BUT STRONGEST/MORE CONVERGENT AREA NOT
NECESSARILY FOCUSED ACROSS THE FORECAST AREA...SO CONFIDENCE ON
WIDESPREAD HEAVY RAINFALL NOT VERY GOOD. THAT SAID...SMALL AREA OF
NRN IA ZONES DID PICK UP 1-2+ INCHES OF RAIN LAST NIGHT AND THAT
AREA APPEARS TO HAVE THE HIGHEST CHANCE OF SIGNIFICANT RAINS
TONIGHT AS MOISTURE REMAINS PLENTIFUL WITH PWATS AROUND 1.5
INCHES. THUS ISSUED A SMALL FLASH FLOOD WATCH NE OF OMAHA TO MATCH
UP WITH DMX WHERE HEAVIER RAIN WAS MORE WIDESPREAD.
DECREASED POPS DIURNALLY ON SUNDAY LIKE TODAY ALTHOUGH IT WAS
NOTED THAT FOR SEVERAL RUNS NOW NAM HAD DEVELOPED A SMALL MCS AND
DROPPED IT SE ACROSS FA DURING THE AFTERNOON. FORECAST WAS NOT
BASED ON THAT SCENARIO. ALSO MODELS HINTING AT MORE LOW LEVEL
MOISTURE WITH LOW CLOUDS POSSIBLY LINGERING INTO THE AFTERNOON.
THUS INCREASED SKY COVER. IF CLOUDS HOLD ALL DAY CONVECTIVE
DEVELOPMENT COULD BE ALTERED AS WELL AS HIGH TEMPERATURES.
OTHERWISE...LIKELY POPS MANY AREAS AGAIN WERE MENTIONED SUN NIGHT.
MONDAY POSSIBLY A VERY SIMILAR SCENARIO...ALTHOUGH FINER DETAILS
PROBABLY IMPACTED BY PREVIOUS PERIODS CONVECTION BOTH DAYS.
SOME INDICATION BY MODELS THAT A FRONT...POSSIBLY AIDED BY
OVERNIGHT CONVECTION...WILL PUSH S INTO NRN ZONES ON TUESDAY AS A
STRONGER WAVE EJECTS ACROSS CANADIAN PRAIRIE. COOLING AT H85
MINIMAL FOR THAT AREA...BUT NE WINDS AND POSSIBLE LOW CLOUDS
COULD KEEP MAX TEMPS COOLER AND THIS COULD NEED ATTENTION IN LATER
FORECASTS. OTHERWISE...THIS BOUNDARY AND UPPER TROUGH BEGINNING TO
APPROACH AREA WILL KEEP AREA ACTIVE TUESDAY/TUE NGT. WEDNESDAY
COULD POSSIBLY BE MORE OF A LULL WITH WARMER TEMPERATURES BEFORE
STRONGER ENERGY PUNCHES ACROSS CNTRL PLAINS WED NGT/THURSDAY
INCREASING COVERAGE/CHCS AGAIN. ALTHOUGH SEVERE POTENTIAL WILL
EXIST INTO TUESDAY...THIS STRONGER TROUGH COULD BRING A HEIGHTENED
RISK OF SVR WEATHER TO AREA LATE NEXT WEEK.
CHERMOK
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...FLASH FLOOD WATCH FROM MIDNIGHT CDT TONIGHT THROUGH SUNDAY
MORNING FOR IAZ043-055-056.
&&
$$
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
629 PM EDT FRI MAY 24 2013
.SYNOPSIS...
A LARGE AREA OF HIGH PRESSURE CENTERED OVER THE WESTERN GREAT LAKES
WILL MOVE LITTLE THROUGH THE WEEKEND...THEN SLIDE TO THE EAST COAST
MONDAY AND TUESDAY. A WARM FRONT WILL DEVELOP OVER THE MISSISSIPPI
VALLEY BY MONDAY AND LIFT NORTH ACROSS THE AREA ON TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
MADE MINOR ADJUSTMENTS TO THE HOURLY TEMPERATURES AND SKY COVER THIS
EVENING FOR THE EARLY EVENING UPDATE. CALLED IT "CLEARING" FOR THE
NE OH/NW PA COUNTIES...OTHERWISE NO CHANGES TO THE CURRENT FORECAST.
EARLIER DISCUSSION...
GIVEN THE TIME OF YEAR AND IMPACT AND HAVE GONE WITH FROST AND
FREEZE HEADLINES FOR THE ENTIRE AREA. IT APPEARS THAT CLEARING
WILL RAPIDLY OCCUR THIS EVENING. WINDS SHOULD ALSO LESSEN. IF
SPEEDS STAY MORE THAN 5 OR 6 MPH OVERNIGHT FREEZING TEMPS WILL BE
HARD TO ACHIEVE. IF FREEZING TEMPS DO OCCUR IT WILL BE ONE OF THE
LATEST FREEZES EVER AT ALL OF THE CLIMATE SITES. TEMPS REMAIN IN
THE 40S MOST AREAS AND SHOULD DROP QUICKLY AFTER SUNSET. SOME
INDICATION THAT HIGH CLOUDS COULD SPILL INTO WESTERN AREAS LATE
TONIGHT. GIVEN THE STRENGTH OF THE HIGH THIS COULD BE A LITTLE
OVERDONE SO HAVE TAKEN THE FROST HEADLINE ALL THE WAY TO KTOL AND
KFDY. LATEST HRRR HAS SURFACE TEMPS TO 34 DEGREES BY 04Z OVER MOST
OF INLAND NE OH AND NW PA. IF THAT OCCURS FROST IS LIKELY BY EARLY
MORNING.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY NIGHT/...
DRY HIGH PRESSURE WILL DOMINATE THROUGH THE HOLIDAY WEEKEND. THE
AREA WILL REMAIN COOL WITH ONLY VERY SLOWLY MODERATING TEMPERATURES.
WILL LIKELY NEED MORE FROST HEADLINES SATURDAY NIGHT IN THE EAST.
EXPECT TEMPS TO STRUGGLE TO GET ABOVE 60 ON SATURDAY AND OUT OF
THE LOWER AND MIDDLE 60S ON SUNDAY. TEMPERATURE MAY GET TO 70 ON
MONDAY BUT THAT WILL STILL BELOW NORMAL. MODELS HAVE BEEN SHOWING
A SYSTEM MOVING OUT OF THE PLAINS MONDAY. A WARM FRONT FROM THIS
SYSTEM WILL BEGIN TO IMPACT THE AREA MONDAY NIGHT AND HAVE PUT
SOME WARM AIR ADVECTION PRECIP IN THE WEST MONDAY NIGHT. THINK DRY
WEATHER WILL PREVAIL IN THE EAST TILL AFTER THE SHORT TERM PERIOD.
GIVEN A LOOK AT UPSTREAM SATELLITE TODAY SKIES SHOULD BE ALMOST
COMPLETELY CLEAR ON SATURDAY WITH JUST SOME HIGH CLOUDS THE
REMAINDER OF THE WEEKEND. HAVE TRENDED TO COOL SIDE OF GUIDANCE
THROUGH THE PERIOD.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
THE BEST CHANCE FOR SHOWERS AND THUNDERSTORMS WILL BE TUESDAY AND
TUESDAY NIGHT AS A WARM FRONT LIFTS THROUGH. IN THE WARM AIR MASS
WEDNESDAY THROUGH FRIDAY THERE COULD BE SOME POP UP SHOWERS AND
THUNDERSTORMS...CONTINUING THE 20 POPS. OTHERWISE A WARMING TREND
WITH HIGHS ABOVE NORMAL. USED A BLEND OF GUIDANCE...ESPECIALLY HPC.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
HIGH PRESSURE IS BUILDING IN THROUGH TONIGHT. THE CLOUDS WILL
SLOWLY DECREASE AND THE CEILINGS ARE RISING AND WILL BE VFR BY MID
AFTERNOON. SKIES SHOULD BE CLEAR BY DARK. NOT EXPECTING MUCH FOG
AT THE TAF SITES BUT SOME MVFR FOG MAY OCCUR AT FAVORED LOCATIONS.
VFR SATURDAY WITH SOME CIRRUS AND A LIGHT NORTHWEST WIND.
.OUTLOOK...NON VFR POSSIBLE IN SHOWERS AND THUNDERSTORMS MONDAY
NIGHT THROUGH TUESDAY.
&&
.MARINE...
DROPPING THE SMALL CRAFT ADVISORY ON THE EXTREME WEST END OF THE
LAKE AS THE HIGH IS BUILDING IN. OTHERWISE NO CHANGES TO THE
HEADLINES. THE ONLY CONCERN IS THAT THE WAVES COULD BE NEAR SMALL
CRAFT ADVISORY CRITERIA SATURDAY AFTERNOON IN THE NORTHWEST
FLOW...THIS WILL HAVE TO BE MONITORED.
OTHERWISE NOT EXPECTING CONDITIONS TO MEET SMALL CRAFT ADVISORY
CONDITIONS ON THE LAKE IN A MAINLY SOUTHWEST FLOW.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...FROST ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM EDT SATURDAY FOR
OHZ003-006>012-017>019-027-028-036-089.
FREEZE WARNING FROM MIDNIGHT TONIGHT TO 9 AM EDT SATURDAY FOR
OHZ013-014-020>023-029>033-037-038-047.
PA...FROST ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM EDT SATURDAY FOR
PAZ001.
FREEZE WARNING FROM MIDNIGHT TONIGHT TO 9 AM EDT SATURDAY FOR
PAZ002-003.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EDT SATURDAY FOR LEZ146>149.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR LEZ144-145.
&&
$$
SYNOPSIS...KOSARIK/KUBINA
NEAR TERM...KOSARIK/KUBINA
SHORT TERM...KUBINA
LONG TERM...KIELTYKA
AVIATION...KIELTYKA
MARINE...KIELTYKA
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
423 PM EDT FRI MAY 24 2013
.SYNOPSIS...
CHILLY HIGH PRESSURE TAKES CHARGE TONIGHT INTO SATURDAY. WARM
FRONT LIFT NORTH INTO THE OHIO VALLEY AND WEST VIRGINIA EARLY
TUESDAY. A WARMING TREND EXPECTED MEMORIAL DAY THROUGH NEXT WEEK.
&&
.NEAR TERM /THROUGH SATURDAY/...
VERY TOUGH FCST TONIGHT REGARDING FROST/FREEZE POTENTIAL. DWPTS
CURRENTLY STRADDLING THE MARGINAL THRESHOLD FOR FROST TONIGHT
GIVEN AFTN MIXING. NOT SURE IF THESE GO LWR NEXT FEW HRS BEFORE
RECOVERING THIS EVE. GUIDANCE FOR METRO AREAS IN THE LOWLANDS RUN
32 TO 40F FROM KHTS TO KCRW. H925 WINDS STAY UP ARND 20 KTS
OVERNIGHT AS SFC HIGH BUILDS IN TO ALLOW WINDS AT THE GROUND TO
TRY TO GO CALM. ALL OF THIS COMPLICATES MATTERS FOR EXPANDING
FROST ADV. HOWEVER...GIVEN TIME OF YEAR AND FACT THAT MOST FOLKS
HAVE SOME OF THEIR VEGGIES IN THE GROUND ALONG WITH ANNUAL PLANT
INVESTMENTS...FELT PRUDENT TO LEAN A LITTLE LIBERAL AND EXPAND TO
ENCOMPASS REST OF CWA SAVE FOR S COAL FIELDS TO SW VA. OUTLYING
AREAS WILL SEE BEST SHOT OF FROST. HEADLINE SHOULD GARNER MORE
ATTENTION FOR FOLKS TO TAKE PRECAUTIONS TO BE ON SAFE SIDE. ALSO
EXPANDED FRZ WARNING TO RALEIGH BASED ON GUIDANCE RANGING FROM 28F
TO 33F. THEY WILL HAVE GET UNDER INVERSION THOUGH GIVEN H925 WINDS
OFF MDLS OVERNIGHT. OTHER CONCERN IS STRATUS OVERNIGHT ACROSS THE
N. NAM HAS BEEN WAY TOO FAST IN ERADICATING THE LLVL MOISTURE VS
RUC WHICH HAS BEEN PRETTY STEADY. RUC SHOWS CLDS LIFTING AND SCT
THIS EVE ACROSS THE N BEFORE REDEVELOPING IN N MTNS BY 06Z. NAM
KEEPS ENTIRE COLUMN DRY BUT HAS NOT HANDLED TDY WELL AT ALL. SO
WILL LEAN TOWARD RUC AND REDEVELOP SOME STRATUS IN N MTNS LATE
TONIGHT. THIS MAY KEEP TEMPS UP TONIGHT ESPECIALLY IN
VALLEYS...BUT STILL FEEL AOB FRZ TEMPS WILL BE REALIZED.
UPR TROF AXIS SHIFTS TO E COAST ON SAT WITH SOME RECOVERY IN TEMPS
COMPARED TO TDY. INHERITED TEMPS LOOKED GOOD AND ONLY NEEDED
TWEAKING SOME...MAINLY ACROSS THE N.
&&
.SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/...
MADE MODIFICATIONS TO THE SHORT TERM FORECAST AS FOLLOWS:
HIGH PRESSURE WILL BE IN CONTROL THROUGH THE WEEKEND...KEEPING DRY
CONDITIONS AREAWIDE. MODELS SHOW A MID LEVEL SHORTWAVE...EVIDENT
IN H5 CHARTS...UNDER NORTHWEST FLOW ALOFT...MOVING ACROSS SOUTHERN
OH...SOUTHEAST INTO NORTHWEST KY. REMOVED ANY POPS FOR THE WEEKEND
AS MOISTURE LOOKS VERY LIMITED OVER WV. IN FACT...THERE COULD BE
SOME CLEARING SATURDAY NIGHT INTO SUNDAY MORNING...KEEPING
TEMPERATURES AT OR JUST BELOW FREEZING OVER POCAHONTAS AND
RANDOLPH COUNTIES. INCLUDED PATCHY FROST OVER NORTHEAST MOUNTAINS.
HIGH PRESSURE MOVES EAST OVER THE MID ATLANTIC STATES KEEPING
INFLUENCE OVER WV FOR A DRY SUNDAY THROUGH MONDAY NIGHT.
MINOR CHANGES TO TEMPERATURES THROUGH THE PERIOD...PERHAPS A
COUPLE DEGREES LOWER CLOSER TO THE COOLER MET.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
ANOTHER SHORTWAVE UNDER NORTHWEST FLOW ALOFT PASSES ACROSS
SOUTHEAST OH AND WV MONDAY AND TUESDAY. AT THE SAME TIME...A WARM
FRONT LIFTS NORTH INTO SOUTHERN OH...ACROSS WV AND VA ORIENTED
WEST TO EAST BY 12Z TUESDAY. THESE TWO FEATURES WILL BE CAPABLE TO
PRODUCE SHOWERS AND STORMS LATE MONDAY INTO TUESDAY AS THE WARM
FRONT MOVES NORTH OF THE AREA BY EARLY WEDNESDAY. INCREASED POPS
TO CHANCE INCLUDING THUNDER IN WEATHER GRIDS ACCORDINGLY.
HIGH PRESSURE TAKES CONTROL BY EARLY WEDNESDAY PROVIDING DRY
WEATHER WITH A SLOW WARMING TREND THROUGH THE REST OF THE WEEK.
TWEAKED COUPLE OF DEGREES DOWN FROM HPC GUIDANCE IN THE EXTENDED
PERIODS.
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
STRATOCU SHOULD BEGIN TO DISSIPATE FROM W TO E BY THIS EVE.
EXCEPTION BEING N LOWLANDS AND ESPECIALLY N MTNS WHERE MVFR
STRATUS MAY REDEVELOP AFTER 06Z. HAVE KEKN WITH SOME BKN MVFR
BASES AS A RESULT. OTHERWISE SFC HIGH WILL BUILD IN AFTER 09Z WITH
SLACKENING WINDS THIS EVE WITH LOSS OF SUN. NW FLOW ALOFT TONIGHT
AND TOMORROW. MAY SEE SOME FG HUG WARMER RVRS WHICH MAY AFFECT RVR
TERMINALS. HAVE SOME MVFR VSBY ATTM WITH BL WINDS HANGING ONTO A
BIT OF A PUFF. VFR CONDITIONS RETURN FOR ALL TOMORROW WITH JUST
SOME PASSING MID CLDS.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z SATURDAY...
FORECAST CONFIDENCE...MEDIUM.
ALTERNATE SCENARIOS: EXTENT OF FG OVERNIGHT IN QUESTION. STRATUS
MAY NOT REDEVELOP ACROSS THE MTNS AS FCST.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 20 21 22 23 00 01 02 03 04 05 06 07
EDT 1HRLY 16 17 18 19 20 21 22 23 00 01 02 03
CRW CONSISTENCY H H H H H H H H H H M M
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H M M
EKN CONSISTENCY M M M M M M M M M M M M
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H M M M M
AFTER 18Z SATURDAY...
IFR CONDITIONS POSSIBLE IN FOG EARLY SATURDAY MORNING.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...FROST ADVISORY FROM 2 AM TO 8 AM EDT SATURDAY FOR WVZ005>011-
013>020-026>032-039-040.
FREEZE WARNING FROM 2 AM TO 8 AM EDT SATURDAY FOR WVZ035>038-
046-047.
OH...FROST ADVISORY FROM 2 AM TO 8 AM EDT SATURDAY FOR OHZ066-067-
075-076-083>087.
KY...FROST ADVISORY FROM 2 AM TO 8 AM EDT SATURDAY FOR KYZ101>103-
105.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/30
NEAR TERM...30
SHORT TERM...ARJ
LONG TERM...ARJ
AVIATION...30
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
355 PM EDT FRI MAY 24 2013
.SYNOPSIS...
CHILLY HIGH PRESSURE TAKES CHARGE TONIGHT INTO SATURDAY. WARM
FRONT IN LOWER OHIO VALLEY GRADUALLY SHIFTS NE TOWARD MEMORIAL DAY
AND TUESDAY.
&&
.NEAR TERM /THROUGH SATURDAY NIGHT/...
VERY TOUGH FCST TONIGHT REGARDING FROST/FREEZE POTENTIAL. DWPTS
CURRENTLY STRADDLING THE MARGINAL THRESHOLD FOR FROST TONIGHT GIVEN
AFTN MIXING. NOT SURE IF THESE GO LWR NEXT FEW HRS BEFORE RECOVERING
THIS EVE. GUIDANCE FOR METRO AREAS IN THE LOWLANDS RUN 32 TO 40F
FROM KHTS TO KCRW. H925 WINDS STAY UP ARND 20 KTS OVERNIGHT AS SFC
HIGH BUILDS IN TO ALLOW WINDS AT THE GROUND TO TRY TO GO CALM. ALL
OF THIS COMPLICATES MATTERS FOR EXPANDING FROST ADV. HOWEVER...GIVEN
TIME OF YEAR AND FACT THAT MOST FOLKS HAVE SOME OF THEIR VEGGIES IN
THE GROUND ALONG WITH ANNUAL PLANT INVESTMENTS...FELT PRUDENT TO
LEAN A LITTLE LIBERAL AND EXPAND TO ENCOMPASS REST OF CWA SAVE FOR S
COAL FIELDS TO SW VA. OUTLYING AREAS WILL SEE BEST SHOT OF FROST.
HEADLINE SHOULD GARNER MORE ATTENTION FOR FOLKS TO TAKE PRECAUTIONS
TO BE ON SAFE SIDE. ALSO EXPANDED FRZ WARNING TO RALEIGH BASED ON
GUIDANCE RANGING FROM 28F TO 33F. THEY WILL HAVE GET UNDER INVERSION
THOUGH GIVEN H925 WINDS OFF MDLS OVERNIGHT. OTHER CONCERN IS STRATUS
OVERNIGHT ACROSS THE N. NAM HAS BEEN WAY TOO FAST IN ERADICATING THE
LLVL MOISTURE VS RUC WHICH HAS BEEN PRETTY STEADY. RUC SHOWS CLDS
LIFTING AND SCT THIS EVE ACROSS THE N BEFORE REDEVELOPING IN N MTNS
BY 06Z. NAM KEEPS ENTIRE COLUMN DRY BUT HAS NOT HANDLED TDY WELL AT
ALL. SO WILL LEAN TOWARD RUC AND REDEVELOP SOME STRATUS IN N MTNS
LATE TONIGHT. THIS MAY KEEP TEMPS UP TONIGHT ESPECIALLY IN
VALLEYS...BUT STILL FEEL AOB FRZ TEMPS WILL BE REALIZED.
UPR TROF AXIS SHIFTS TO E COAST ON SAT WITH SOME RECOVERY IN TEMPS
COMPARED TO TDY. INHERITED TEMPS LOOKED GOOD AND ONLY NEEDED
TWEAKING SOME...MAINLY ACROSS THE N.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
MOST NOTABLE CHANGES MADE TOWARD MEMORIAL DAY. TIMING THE EVENTUAL
NORTHEAST MOVEMENT AS A WARM FRONT...OF THE FRONTAL ZONE SETTING UP
OVER THE LOWER OHIO VALLEY INTO THE TENNESSEE VALLEY IS A
CHALLENGE.
ONE DISTURBANCE RIDES FROM NW TO SE OVERNIGHT SATURDAY NIGHT INTO
EARLY SUNDAY...BUT WILL KEEP ANY SPOTTY LIGHT RAIN TO OUR SW-S. DID
HAVE MORE CLOUDS OVER OUR SOUTHERN COUNTIES IN THE FORM OF SOME
PATCHY MID/HIGH CLOUDS. FURTHER NORTH...SATURDAY NIGHT WILL STILL
BE MOSTLY CLEAR AND CHILLY ESPECIALLY FOR NORTHERN AND CENTRAL WEST
VIRGINIA. DID INCLUDE SOME FROST IN OUR CENTRAL WV MOUNTAIN
COUNTIES FOR THE EARLY DAWN SUNDAY.
WILL INCREASE POPS ON MONDAY...THINKING THE WARM FRONT WILL BEGIN
LIFTING NORTHEAST...AT LEAST OVER THE MIDWEST...LEAVING US
VULNERABLE DOWNSTREAM. HOW ACTIVE THE WARM FRONT IS...IS ANOTHER
DILEMMA.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
HIGH PRESSURE REMAINS IN CONTROL TO AT LEAST EARLY WEDNESDAY
PROVIDING DRY WEATHER WITH A SLOW WARMING TREND.
ANOTHER MID LEVEL SHORTWAVE WILL MOVE THROUGH SUNDAY NIGHT FOR LOW
CHANCE FOR RAIN SHOWERS INTO MONDAY.
A WARM FRONT DEVELOPS AS IT APPROACHES THE REGION ON MONDAY. AS A
RESULT...THERE WILL BE A CHANCE OF SHOWERS AND STORMS MONDAY AND
TUESDAY...MAINLY DURING THE AFTERNOON AND EVENING HOURS.
FOR SATURDAY...TEMPERATURES SHOULD BE NEAR NORMAL WITH DAYTIME
HIGHS IN THE 70S ACROSS LOWLANDS...WITH 60S ACROSS THE HIGHER
ELEVATIONS. TEMPERATURES WILL CONTINUE TO CLIMB IN THE UPPER TO
MID 80S BY THE END OF THE WEEK. LOWS WILL RANGING IN THE 60S.
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
STRATOCU SHOULD BEGIN TO DISSIPATE FROM W TO E BY THIS EVE.
EXCEPTIONG BEING N LOWLANDS AND ESPECIALLY N MTNS WHERE MVFR
STRATUS MAY REDEVELOP AFTER 06Z. HAVE KEKN WITH SOME BKN MVFR
BASES AS A RESULT. OTHERWISE SFC HIGH WILL BUILD IN AFTER 09Z WITH
SLACKENING WINDS THIS EVE WITH LOSS OF SUN. NW FLOW ALOFT TONIGHT
AND TOMORROW. MAY SEE SOME FG HUG WARMER RVRS WHICH MAY AFFECT RVR
TERMINALS. HAVE SOME MVFR VSBY ATTM WITH BL WINDS HANGING ONTO A
BIT OF A PUFF. VFR CONDITIONS RETURN FOR ALL TOMORROW WITH JUST
SOME PASSING MID CLDS.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z SATURDAY...
FORECAST CONFIDENCE...MEDIUM.
ALTERNATE SCENARIOS: EXTENT OF FG OVERNIGHT IN QUESTION. STRATUS
MAY NOT REDEVELOP ACROSS THE MTNS AS FCST.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 20 21 22 23 00 01 02 03 04 05 06 07
EDT 1HRLY 16 17 18 19 20 21 22 23 00 01 02 03
CRW CONSISTENCY H H H H H H H H H H M M
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H M M
EKN CONSISTENCY M M M M M M M M M M M M
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H H H H H H H H M M M M
AFTER 18Z SATURDAY...
IFR CONDITIONS POSSIBLE IN FOG EARLY SATURDAY MORNING.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...FROST ADVISORY FROM 2 AM TO 8 AM EDT SATURDAY FOR WVZ005>011-
013>020-026>032-039-040.
FREEZE WARNING FROM 2 AM TO 8 AM EDT SATURDAY FOR WVZ035>038-
046-047.
OH...FROST ADVISORY FROM 2 AM TO 8 AM EDT SATURDAY FOR OHZ066-067-
075-076-083>087.
KY...FROST ADVISORY FROM 2 AM TO 8 AM EDT SATURDAY FOR KYZ101>103-
105.
VA...NONE.
&&
$$
SYNOPSIS...ARJ/30
NEAR TERM...30
SHORT TERM...KTB
LONG TERM...ARJ
AVIATION...30
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
321 PM EDT FRI MAY 24 2013
.SYNOPSIS...
A LARGE AREA OF HIGH PRESSURE CENTERED OVER THE GREAT LAKES WILL
MOVE LITTLE THROUGH THE WEEKEND. THE HIGH WILL MOVE OFF TO THE
NORTHEAST MONDAY AND TUESDAY. THIS WILL ALLOW A WARM FRONT TO LIFT
NORTH INTO THE REGION ON TUESDAY.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
GIVEN THE TIME OF YEAR AND IMPACT AND HAVE GONE WITH FROST AND
FREEZE HEADLINES FOR THE ENTIRE AREA. IT APPEARS THAT CLEARING
WILL RAPIDLY OCCUR THIS EVENING. WINDS SHOULD ALSO LESSEN. IF
SPEEDS STAY MORE THAN 5 OR 6 MPH OVERNIGHT FREEZING TEMPS WILL BE
HARD TO ACHIEVE. IF FREEZING TEMPS DO OCCUR IT WILL BE ONE OF THE
LATEST FREEZES EVER AT ALL OF THE CLIMATE SITES. TEMPS REMAIN IN
THE 40S MOST AREAS AND SHOULD DROP QUICKLY AFTER SUNSET. SOME
INDICATION THAT HIGH CLOUDS COULD SPILL INTO WESTERN AREAS LATE
TONIGHT. GIVEN THE STRENGTH OF THE HIGH THIS COULD BE A LITTLE
OVERDONE SO HAVE TAKEN THE FROST HEADLINE ALL THE WAY TO KTOL AND
KFDY. LATEST HRRR HAS SURFACE TEMPS TO 34 DEGREES BY 04Z OVER MOST
OF INLAND NE OH AND NW PA. IF THAT OCCURS FROST IS LIKELY BY EARLY
MORNING.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY NIGHT/...
DRY HIGH PRESSURE WILL DOMINATE THROUGH THE HOLIDAY WEEKEND. THE
AREA WILL REMAIN COOL WITH ONLY VERY SLOWLY MODERATING TEMPERATURES.
WILL LIKELY NEED MORE FROST HEADLINES SATURDAY NIGHT IN THE EAST.
EXPECT TEMPS TO STRUGGLE TO GET ABOVE 60 ON SATURDAY AND OUT OF
THE LOWER AND MIDDLE 60S ON SUNDAY. TEMPERATURE MAY GET TO 70 ON
MONDAY BUT THAT WILL STILL BELOW NORMAL. MODELS HAVE BEEN SHOWING
A SYSTEM MOVING OUT OF THE PLAINS MONDAY. A WARM FRONT FROM THIS
SYSTEM WILL BEGIN TO IMPACT THE AREA MONDAY NIGHT AND HAVE PUT
SOME WARM AIR ADVECTION PRECIP IN THE WEST MONDAY NIGHT. THINK DRY
WEATHER WILL PREVAIL IN THE EAST TILL AFTER THE SHORT TERM PERIOD.
GIVEN A LOOK AT UPSTREAM SATELLITE TODAY SKIES SHOULD BE ALMOST
COMPLETELY CLEAR ON SATURDAY WITH JUST SOME HIGH CLOUDS THE
REMAINDER OF THE WEEKEND. HAVE TRENDED TO COOL SIDE OF GUIDANCE
THROUGH THE PERIOD.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
THE BEST CHANCE FOR SHOWERS AND THUNDERSTORMS WILL BE TUESDAY AND
TUESDAY NIGHT AS A WARM FRONT LIFTS THROUGH. IN THE WARM AIRMASS
WEDNESDAY THROUGH FRIDAY THERE COULD BE SOME POP UP SHOWERS AND
THUNDERSTORMS...CONTINUING THE 20 POPS. OTHERWISE A WARMING TREND
WITH HIGHS ABOVE NORMAL. USED A BLEND OF GUIDANCE...ESPECIALLY HPC.
&&
.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
HIGH PRESSURE IS BUILDING IN THROUGH TONIGHT. THE CLOUDS WILL
SLOWLY DECREASE AND THE CEILINGS ARE RISING AND WILL BE VFR BY MID
AFTERNOON. SKIES SHOULD BE CLEAR BY DARK. NOT EXPECTING MUCH FOG
AT THE TAF SITES BUT SOME MVFR FOG MAY OCCUR AT FAVORED LOCATIONS.
VFR SATURDAY WITH SOME CIRRUS AND A LIGHT NORTHWEST WIND.
.OUTLOOK...NON VFR POSSIBLE IN SHOWERS AND THUNDERSTORMS MONDAY
NIGHT THROUGH TUESDAY.
&&
.MARINE...
DROPPING THE SMALL CRAFT ADVISORY ON THE EXTREME WEST END OF THE
LAKE AS THE HIGH IS BUILDING IN. OTHERWISE NO CHANGES TO THE
HEADLINES. THE ONLY CONCERN IS THAT THE WAVES COULD BE NEAR SMALL
CRAFT ADVISORY CRITERIA SATURDAY AFTERNOON IN THE NORTHWEST
FLOW...THIS WILL HAVE TO BE MONITORED.
OTHERWISE NOT EXPECTING CONDITIONS TO MEET SMALL CRAFT ADVISORY
CONDITIONS ON THE LAKE IN A MAINLY SOUTHWEST FLOW.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...FROST ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM EDT SATURDAY FOR
OHZ003-006>012-017>019-027-028-036-089.
FREEZE WARNING FROM MIDNIGHT TONIGHT TO 9 AM EDT SUNDAY FOR
OHZ013-014-020>023-029>033-037-038-047.
PA...FROST ADVISORY FROM MIDNIGHT TONIGHT TO 9 AM EDT SATURDAY FOR
PAZ001.
FREEZE WARNING FROM MIDNIGHT TONIGHT TO 9 AM EDT SUNDAY FOR
PAZ002-003.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EDT SATURDAY FOR LEZ146>149.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR LEZ142>145.
&&
$$
SYNOPSIS...KUBINA
NEAR TERM...KUBINA
SHORT TERM...KUBINA
LONG TERM...KIELTYKA
AVIATION...KIELTYKA
MARINE...KIELTYKA
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1108 AM EDT FRI MAY 24 2013
.SYNOPSIS...
MUCH COOLER AIR TURNS DRIER AND TODAY PROGRESSES. CHILLY HIGH
PRESSURE TAKES CHARGE TONIGHT INTO SATURDAY. WARM FRONT IN LOWER
OHIO VALLEY GRADUALLY SHIFTS NE TOWARD MEMORIAL DAY AND TUESDAY.
&&
.NEAR TERM /THROUGH SATURDAY/...
STRATOCU HANGING TOUGH ATTM ACROSS MUCH OF THE AREA...WITH AREAS
ALONG AND E OF I79 CORRIDOR MAINLY OVC. BUMPED POPS UP TO LKLY FOR
ANOTHER HR OR TWO ACROSS N MTNS FOR SOME SHRA. SNOWSHOE HANGING
ARND 34F...HOWEVER...MOISTURE DEPTH ONLY REACHES UP TO ABOUT -3F
SO KEPT THINGS LIQUID. TRIED TO DELAY SCOURING OUT OF LLVL
MOISTURE PER RUC TRENDS...PRIMARILY ACROSS THE MTNS. SHOULD SEE
MORE STREAKY NATURE TO FLAT STRATOCU ACROSS THE LOWLANDS WITH MORE
SUNSHINE BEING OBSERVED.
KNOCKED TEMPS DOWN A COUPLE DEGREES FOR THIS AFTN PER LATEST
TRENDS AND LAMP GUIDANCE ESPECIALLY ACROSS THE HIGH TERRAIN.
WILL BE FIGURING OUT IF FROST ADV NEEDS EXPANDING FOR AFTN
PACKAGE. SFC HIGH BUILDS IN OVER NIGHT ALLOWING WINDS AT SFC TO GO
CALM...BUT H925 WINDS STAY UP ARND 20 KTS. ALSO OF CONCERN IS
STRATOCU TRYING TO REDEVELOP ACROSS N MTNS AND ADJ LOWLANDS
TONIGHT PER RUC AND TO A LESSER DEGREE HI RES WRF MDLS. NAM KEEPS
ENTIRE COLUMN DRY.
PREVIOUS DISCUSSION BELOW...
FINAL COLD FRONT PUSHING ACROSS CWA AT THIS TIME...AT 08Z IT WAS
STRETCHING FROM CLARKSBURG SOUTH TO AROUND THE WV/VA/KY
INTERSECTION. STILL SEEING SOME GUSTY WINDS ALONG AND JUST BEHIND
THE FRONT...WHICH SHOULD SUBSIDE SOME EARLY THIS MORNING BEFORE
PICKING BACK UP WITH MIXING TODAY. DEWPOINTS ALSO DROPPING INTO
THE UPPER 30S BEHIND THE FRONT...AND EXPECT SKIES TO GRADUALLY
CLEAR FROM WEST TO EAST ACROSS THE FORECAST AREA TODAY AS THE
MOISTURE CONTINUES EAST AND COOL HIGH PRESSURE BEGINS TO BUILD
OVER LAKE MICHIGAN. HIGHS TODAY WILL BE 10-15 DEGREES COOLER THAN
YESTERDAY...MAV/MET FAIRLY CLOSE...AND SETTLED GENERALLY BETWEEN
THE TWO.
THE COOL HIGH PRESSURE WILL MOVE OVER FORECAST AREA TONIGHT...WITH
AN UNSEASONABLY CHILLY START TO THE MEMORIAL DAY WEEKEND. MAV A BIT
COOLER THAN THE MET...AND AGAIN SETTLED IN BETWEEN. THIS GIVES
AROUND...TO JUST BELOW FREEZING FOR THE NORTHERN MOUNTAINS...SO
OPTED FOR A FREEZE WARNING THERE. A BIT HARDER TO FIGURE OUT WHERE
FROST MAY FORM DUE TO THE WARM...WET GROUND...CONTINUED BREEZE
OVERNIGHT...AND RELATIVELY SHORT NIGHT TO BOOT. DECIDED ON A FROST
ADVISORY ACROSS NORTHERN TWO TIERS OF COUNTIES...WITH CONTINUED
MENTION IN HWO FOR THE REST OF THE CWA. DESPITE TEMPERATURES BEING
COLD ENOUGH IN PARTS OF THE SOUTHERN MOUNTAINOUS COUNTIES...THINKING
IT WILL REMAIN MIXY ENOUGH TO NIX ANY FROST FORMATION EVEN AT 34-36
DEGREES. AT ANY RATE...CAMPERS CELEBRATING THE UNOFFICIAL START OF
SUMMER...OR THOSE WITH EARLY MORNING SOCCER OR BASEBALL WILL WAKE UP
TO A CHILLY SATURDAY MORNING.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
MOST NOTABLE CHANGES MADE TOWARD MEMORIAL DAY. TIMING THE EVENTUAL
NORTHEAST MOVEMENT AS A WARM FRONT...OF THE FRONTAL ZONE SETTING UP
OVER THE LOWER OHIO VALLEY INTO THE TENNESSEE VALLEY IS A
CHALLENGE.
ONE DISTURBANCE RIDES FROM NW TO SE OVERNIGHT SATURDAY NIGHT INTO
EARLY SUNDAY...BUT WILL KEEP ANY SPOTTY LIGHT RAIN TO OUR SW-S. DID
HAVE MORE CLOUDS OVER OUR SOUTHERN COUNTIES IN THE FORM OF SOME
PATCHY MID/HIGH CLOUDS. FURTHER NORTH...SATURDAY NIGHT WILL STILL
BE MOSTLY CLEAR AND CHILLY ESPECIALLY FOR NORTHERN AND CENTRAL WEST
VIRGINIA. DID INCLUDE SOME FROST IN OUR CENTRAL WV MOUNTAIN
COUNTIES FOR THE EARLY DAWN SUNDAY.
WILL INCREASE POPS ON MONDAY...THINKING THE WARM FRONT WILL BEGIN
LIFTING NORTHEAST...AT LEAST OVER THE MIDWEST...LEAVING US
VULNERABLE DOWNSTREAM. HOW ACTIVE THE WARM FRONT IS...IS ANOTHER
DILEMMA.
&&
.LONG TERM /TUESDAY THROUGH THURSDAY/...
HIGH PRESSURE REMAINS IN CONTROL TO AT LEAST EARLY WEDNESDAY
PROVIDING DRY WEATHER WITH A SLOW WARMING TREND.
ANOTHER MID LEVEL SHORTWAVE WILL MOVE THROUGH SUNDAY NIGHT FOR LOW
CHANCE FOR RAIN SHOWERS INTO MONDAY.
A WARM FRONT DEVELOPS AS IT APPROACHES THE REGION ON MONDAY. AS A
RESULT...THERE WILL BE A CHANCE OF SHOWERS AND STORMS MONDAY AND
TUESDAY...MAINLY DURING THE AFTERNOON AND EVENING HOURS.
FOR SATURDAY...TEMPERATURES SHOULD BE NEAR NORMAL WITH DAYTIME
HIGHS IN THE 70S ACROSS LOWLANDS...WITH 60S ACROSS THE HIGHER
ELEVATIONS. TEMPERATURES WILL CONTINUE TO CLIMB IN THE UPPER TO
MID 80S BY THE END OF THE WEEK. LOWS WILL RANGING IN THE 60S.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
FOR THE MOST PART SHOWERS HAVE ENDED ACROSS THE FORECAST
AREA...WITH MVFR CEILINGS REMAINING ACROSS THE LOWLANDS AND LOW
MVFR TO IFR IN THE MOUNTAINS. CEILINGS SHOULD GRADUALLY IMPROVE TO
VFR FROM WEST TO EAST TODAY. BREEZY TO GUSTY WINDS WILL CONTINUE
TODAY OUT OF THE N/NW...DECREASING SOME AS THE SUN SETS TONIGHT.
DRY AIR FILTERING IN SHOULD KEEP WIDESPREAD FOG CHANCES AT BAY
ACROSS THE LOWLANDS TONIGHT...AND WINDS IN THE HIGHER TERRAIN
SHOULD ALSO KEEP ANY DENSE FOG AWAY. WITH THAT SAID...VERY CHILLY
AIR OVER RELATIVE WARM WATER IN THE RIVERS COULD PRODUCE SOME
LOCALIZED MVFR FOG BY EARLY SATURDAY MORNING IN RIVER VALLEYS.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z SATURDAY...
FORECAST CONFIDENCE...HIGH.
ALTERNATE SCENARIOS: TIMING OF DISSIPATION OF MVFR/IFR CEILINGS
THIS MORNING MAY VARY A COUPLE OF HOURS.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
UTC 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
EDT 1HRLY 10 11 12 13 14 15 16 17 18 19 20 21
CRW CONSISTENCY H H H H H H H H H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY M H M H H H H H H H H H
EKN CONSISTENCY L H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY H M H H H H H H H H H H
AFTER 12Z SATURDAY...
IFR CONDITIONS POSSIBLE IN FOG EARLY SATURDAY MORNING.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...FROST ADVISORY FROM 2 AM TO 8 AM EDT SATURDAY FOR WVZ009>011-
019-020-028>032-039-040.
FREEZE WARNING FROM 2 AM TO 8 AM EDT SATURDAY FOR WVZ037-038-
046-047.
OH...FROST ADVISORY FROM 2 AM TO 8 AM EDT SATURDAY FOR OHZ066-067-
075-076.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...KTB/MZ
NEAR TERM...MZ/30
SHORT TERM...KTB
LONG TERM...ARJ
AVIATION...MZ
EQUIPMENT...
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
855 AM EDT FRI MAY 24 2013
.SYNOPSIS...
HIGH PRESSURE OF CANADIAN ORIGIN WILL BUILD INTO THE REGION TODAY
PROVIDING DRY WEATHER AND CONSIDERABLY COOLER TEMPERATURES. THIS
RIDGE OF HIGH PRESSURE WILL SLIDE EAST ACROSS THE REGION...OFFERING
DRY CONDITIONS THROUGH THE HOLIDAY WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LOW CLOUDS CONTINUE TO MOVE SOUTH ACROSS THE REGION. EXPECT THIS
TO EVENTUALLY MIX OUT WITH THE AFTERNOON BECOMING MAINLY SUNNY.
UPDATED TO LINGER CLOUDS A LITTLE LONGER BASED ON OBSERVATIONAL
TRENDS AND LATEST RAP FORECASTS. TEMPERATURES LOOK REASONABLE
BASED ON 12Z SOUNDING.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
IN NW FLOW PATTERN...SFC HIGH PRESSURE TO BUILD SE BECOMING CENTERED
OVER THE REGION SATURDAY. LIGHT WINDS...AND CLEAR SKIES WILL LEAD TO
A FAVORABLE RADIATIONAL COOLING SETUP. LOW TEMPERATURES TO RANGE
FROM THE MID/UPR 30S FAR EAST TO THE LOWER 40S WEST. HAVE INCLUDED A
MENTION OF PATCHY FROST IN THE FAR EASTERN COUNTIES. WILL CONTINUE
TO HIGHLIGHT THIS POSSIBILITY OF FROST IN THE HWO PRODUCT.
EXPECT MAINLY HIGH LEVEL CLOUDS TO SPILL OVER THE UP STREAM RIDGE
WITH SKIES BECOMING PARTLY CLOUDY OVER THE SW SATURDAY. WAA PRECIP
AND DEEPER MOISTURE EXPECTED TO REMAIN TO OUR SW. TEMPERATURES WILL
BEGIN TO MODERATE WITH HIGHS STILL 8 TO 10 DEGREES BELOW NORMAL.
EXPECT HIGHS TO RANGE FROM THE MID 60S NE TO THE UPR 60S SW.
SATURDAY NIGHTS LOWS TO CONTINUE BELOW NORMAL RANGING FROM THE LOWER
40S NE TO ABOUT 50 SW...WHERE MORE CLOUDS ARE EXPECTED.
A DISTURBANCE ROUNDING THE RIDGE WILL RESULT IN PRECIP SPILLING SE
INTO THE LOWER OHIO VALLEY. IT IS NOT OUT OF THE QUESTION THAT A
RAIN SHOWER SPILL INTO OUR FAR SW SUNDAY BUT WITH BEST LIFT AND MSTR
TO OUR SW...WILL MAINTAIN A DRY FCST. TEMPERATURES WILL CONTINUE TO
MODERATE WITH HIGHS RANGING FROM THE UPR 60S NE TO ABOUT 70 SW.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
UPPER LEVEL RIDGE IN THE CENTRAL CONUS WILL PREVAIL WITH GENERAL
NORTHWEST FLOW IN THE OHIO VALLEY. GFS IS SHOWING A S/W
UNDERCUTTING H5 RIDGE AND BRINGING PRECIPITATION TO THE REGION
MONDAY. THIS APPEARS TO BE CONSISTENT FROM YESTERDAYS FORECAST BUT
THE EUROPEAN IS ALSO CONSISTENT WITH SHOWING THIS FEATURE MUCH
FURTHER SOUTHWEST AS AN ELEVATED CONVERGENT BAND AT THIS TIME.
THE EUROPEAN PERMITS THIS UNDERCUTTING OF THE ESTABLISHED H5 RIDGE
ON TUESDAY AND IS SHOWING A MORE TRADITIONAL WARM FRONTAL FEATURES
IN THE OHIO VALLEY...ALSO SUPPORTED BY THE GFS AND CANADIAN MODEL.
THIS FRONT IS VERY BROAD IN NATURE AND FORECAST IS UNCERTAIN AS TO
IF THERE WILL BE ENOUGH OF A GRADIENT TO HELP FORCE SHOWERS IN A
SOMEWHAT UNFAVORABLE UPPER LEVEL PATTERN...UNDERNEATH THE AXIS OF
THE H5 RIDGE.
UPPER LEVEL FLOW IS SHOWING A BROADENING OF THE H5 RIDGE AS IT MOVES
OVER THE EASTERN THIRD OF THE COUNTRY. AM CONTINUING THE INCREASED
POPS EXPECTING MID LEVEL DISTURBANCES TO UNDERCUT THE RIDGE AFTER
MONDAY BUT INCREASING THROUGH THE WEEK.
EXPECT A GRADUAL WARM UP EACH DAY...STARTING IN THE UPPER 60S TO
AROUND 70 SUNDAY...WARMING TO NEAR 80/LOW 80S BY WED...POSSIBLY
REACHING MID 80S BY THURSDAY. PM LOWS WILL BE COMFORTABLY COOL
AROUND 50 MON MORNING UNDER A DRY AIRMASS AND THEN WARM PAST THE
CLIMATOLOGICAL NORMS TO REACH MID 60S BY THE LATTER PART OF THE WEEK.
&&
.AVIATION /13Z FRIDAY THROUGH TUESDAY/...
CLOUDS WILL LINGER ACROSS THE TERMINALS FOR SEVERAL MORE HOURS
WITH BRIEF PERIODS OF MVFR CEILINGS POSSIBLE. CLOUDS SHOULD
DIMINISH AFTER 18Z. NORTH WINDS MAY BECOME GUSTY THROUGH THE DAY.
WINDS WILL BECOME LIGHT AFTER 00Z SATURDAY AS HIGH CLOUDS BEGIN TO
MOVE IN ON A NORTHWESTERLY FLOW ALOFT. THE LIGHT WINDS MAY ALLOW
MIST TO FORM AT LUK LATE TONIGHT. CVG CAN EXPECT MID AND HIGH
CLOUDS AND LIGHT EAST WINDS AFTER 12Z SATURDAY.
OUTLOOK...NO SIGNIFICANT WEATHER EXPECTED.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...NONE.
IN...NONE.
&&
$$
SYNOPSIS...AR
NEAR TERM...
SHORT TERM...AR
LONG TERM...FRANKS
AVIATION...
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
1026 PM CDT SAT MAY 25 2013
.DISCUSSION...ACTIVITY HAS QUIETED DOWN ACROSS SOUTH
TEXAS...HOWEVER SUFFICIENT CAPE WITH WEAKENING CIN MAY ALLOW FOR
REDEVELOPMENT SUNDAY MORNING AS A SHORTWAVE/TROUGH MOVES OVERHEAD.
THETA-E ADVECTION AND MOISTURE CONVERGENCE APPEARS TO BE BEST
ALONG THE COAST LATE TONIGHT...MOVING FURTHER INLAND THROUGH THE
REST OF THE MORNING. ONLY MADE ADJUSTMENTS TO POPS.
&&
.PREV DISCUSSION... /ISSUED 609 PM CDT SAT MAY 25 2013/
DISCUSSION...SEE 00Z AVIATION DISCUSSION.
AVIATION...MVFR CONDITIONS ARE EXPECTED TO DEVELOP AGAIN AFTER
SUNSET...STARTING AT KCRP AND KALI BETWEEN 03Z-04Z...THEN AT KVCT
ABT 06Z...WITH MVFR CIGS AT KLRD BFR 12Z. VFR CONDITIONS SHOULD
DEVELOP AOA 16Z AREA-WIDE. CONCERNING THUNDER/SHRA IN TAFS...ONLY
HAVE THAT IN KVCT FOR NOW ENDING BY 03Z. THINK ANY OTHER
CONVECTION TONIGHT WILL BE AWAY FROM TERMINALS...AND ANY WHICH MAY
DEVELOP OVERNIGHT WILL BE TOO ISOLATED. CONCERNING WINDS...
SOUTHEAST WINDS WILL TAPER OFF TONIGHT...WITH INCREASING WINDS
WITH GUSTS AROUND 18Z...EXCEPT AT KLRD WHERE WINDS WILL BE SE WITH
GUSTS LIMITED IF ANY.
PREV DISCUSSION... /ISSUED 420 PM CDT SAT MAY 25 2013/
SHORT TERM...(TODAY THROUGH SUNDAY NIGHT)...ACTIVE AFTERNOON WITH A
WEAK PATTERN CONTINUES. GOOD CAPE...BUT MARGINAL LAPSE RATES AND
WEAK SHEAR...BUT CONTINUE TO HAVE STORMS DEVELOP...A FEW PRODUCING
BRIEF FUNNEL CLOUDS OR TORNADOES. FLOOD CONCERNS ARE DECREASING AS
STORMS ARE MOVING BETTER THAN EARLIER IN THE DAY...AND NOT
TRAINING.
INITIAL VORT MAX CURRENTLY INTO NORTHEAST PORTIONS OF OUR FORECAST
AREA BUT RUC GUIDANCE SHOWS ADDITIONAL VORT MAX COMING ACROSS
OVERNIGHT. HAVE INCREASE POPS TO 30 OVERNIGHT...BUT SORT OF A
HEDGE BET AT THIS POINT AS MESO MODELS ARENT SHOWING A WHOLE LOT.
IF WE GET CONVECTION TO RE FIRE WITH THIS VORT MAX COULD BECOME
ANOTHER MORE WIDE SPREAD EVENT OVERNIGHT. WILL KEEP ISOLATED
SHOWERS AND STORMS IN THE FORECAST FOR TOMORROW AS WEAK SHORTWAVES
CONTINUE TO AFFECT THE AREA. BY SUNDAY AFTERNOON THINGS SHOULD
QUIET DOWN WITH PRECIP MOVING OUT OF THE AREA. COULD EVEN SEE SOME
BREAKS IN THE CLOUDS BY THE AFTERNOON. MILD MIN TEMPS AND WARM
HIGHS CONTINUE.
LONG TERM...(MONDAY THROUGH FRIDAY)...DID NOT MAKE MANY CHANGES
TO THE EXTENDED PART OF THE FORECAST. UPPER LEVEL RIDGE WILL BUILD
IN FOR MONDAY WITH DRIER AIR ACROSS THE AREA. TEMPERATURES WILL
REBOUND FOR THE EARLY PART OF THE WEEK WITH UPPER 90S OUT WEST TO
UPPER 80S OVER THE VICTORIA CROSSROADS. RIDGE WILL BEGIN TO SHIFT
EASTWARD TUESDAY INTO WEDNESDAY. MODELS NOW INDICATE UPPER TROUGH
MOVING INTO THE FOUR CORNERS WEDNESDAY AND INTO THE PLAINS WEDNESDAY
NIGHT. MOISTURE DOES INCREASE BY WEDNESDAY OVER THE RIO GRANDE
PLAINS BUT BELIEVE ATMOSPHERE MAY BE CAPPED...SO WILL CONTINUE WITH
POPS BELOW MENTIONABLE LEVELS. LEFT INHERITED LOW END POPS IN FOR
THURSDAY FOR THE TIME BEING...BUT CAPPING COULD BE AN ISSUE THIS DAY
AS WELL. ABOVE NORMAL TEMPERATURES WILL CONTINUE THROUGH THE
EXTENDED.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 75 88 75 89 75 / 30 20 10 10 10
VICTORIA 73 87 73 89 73 / 30 20 10 10 10
LAREDO 75 92 74 98 75 / 30 20 10 10 10
ALICE 73 89 74 92 74 / 30 20 10 10 10
ROCKPORT 76 86 76 87 76 / 30 20 10 10 10
COTULLA 72 91 73 94 73 / 30 20 10 10 10
KINGSVILLE 74 89 74 91 75 / 30 20 10 10 10
NAVY CORPUS 75 84 76 87 77 / 30 20 10 10 10
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
CB/85...SHORT TERM
AREA FORECAST DISCUSSION...UPDATED
NWS LUBBOCK TX
1024 PM CDT SAT MAY 25 2013
.UPDATE...
ANOTHER QUICK UPDATE TO RECONFIGURE POPS FAVORING THE NORTH-
CENTRAL...SOUTH-CENTRAL AND SOUTHWEST ZONES...GIVEN THE CURRENT
RADAR TRENDS. OVERALL WEAKENING STORM INTENSITIES SHOULD CONTINUE
AS THE BOUNDARY LAYER COOLS...THOUGH GUSTY WINDS...AREAS OF
BLOWING DUST AND BRIEF HEAVY RAINS WILL STILL BE POSSIBLE FOR SOME
TIME AS THE CONVECTIVE COMPLEXES GRADUALLY GUST OUT. NO OTHER
CHANGES MADE TO THE GRIDS ATTM.
&&
.PREV DISCUSSION... /ISSUED 652 PM CDT SAT MAY 25 2013/
UPDATE...
QUICK UPDATE TO INCREASE POPS ACROSS THE FAR WESTERN COUNTIES THIS
EVENING...PARTICULARLY THE NORTHWESTERN MOST ZONES...WHERE
STRONG/SEVERE CONVECTION IS POISED TO MOVE IN. HAIL AND WIND
THREAT MAY PERSIST FOR A COUPLE OF HOURS AS STORMS MOVE INTO
STRONG INSTABILITY...THOUGH EXPECT A GRADUALLY WEAKENING TREND
AFTER SUNSET. STILL...GUSTY /AND DUSTY/ OUTFLOW COULD ORGANIZE AND
MAKE A PUSH EASTWARD ACROSS THE CAPROCK. UPDATED PRODUCTS HAVE
BEEN SENT.
PREV DISCUSSION... /ISSUED 631 PM CDT SAT MAY 25 2013/
AVIATION...
AVIATION CONCERNS ARE -TSRA AND/OR STRONG OUTFLOW BOUNDARY AT KLBB
LATE THIS EVENING...AND MVFR CEILINGS AT KCDS EARLY SUNDAY
MORNING. T-STORMS IN EASTERN NM WILL GRADUALLY MOVE EAST THIS
EVENING...BUT WILL LIKELY DECAY BEFORE REACHING KLBB. THE PASSAGE
OF AN OUTFLOW BOUNDARY IS CONSIDERED MORE LIKELY AT THIS
TIME. WE HAVE VERY LOW CONFIDENCE IN WIND SPEEDS ASSOC. WITH ANY
BOUNDARY...SO WE HAVE KEPT THEM ON THE CONSERVATIVE SIDE IN A
TEMPO MENTION. AT KCDS...WE EXPECT LOW STRATUS TO MOVE IN AROUND
10 UTC...THEN GRADUALLY SCOUR OUT SUN MORN. VFR CONDITIONS ARE
EXPECTED AREA-WIDE BY MIDDAY...WITH WIDELY SCATTERED CB DEVELOPING
BY MID TO LATE AFTERNOON.
PREV DISCUSSION... /ISSUED 339 PM CDT SAT MAY 25 2013/
SHORT TERM...
MOIST UPSLOPE FLOW ACROSS EASTERN NEW MEXICO HAS ALREADY SUPPORTED
SCATTERED TSTMS FROM THE SACRAMENTOS NORTH TO SANTA ROSA. A SECOND
AREA OF INTEREST IS EVIDENT ON VIS SATELLITE ALONG THE MESCALERO
ESCARPMENT WHERE AGITATED CU HAVE RECENTLY DEVELOPED. HRRR AND
NAM-WRF BOTH PROG TSTM DEVELOPMENT ALONG THIS CU LINE BEFORE 00Z
AND CARRY IT EASTWARD TO VARIOUS DEGREES WITHIN 20 KNOTS OF
700-500MB FLOW. CONSIDERING CINH IS TRENDING NEGLIGIBLE ALONG THE
NM/TX STATE LINE AND SBCAPE IS AROUND 2K J/KG...HAVE ADDED SEVERE
MENTION TO OUR WESTERNMOST COUNTIES WHERE THIS ACTIVITY WILL LIKELY
PEAK IN INTENSITY BEFORE DIMINISHING THEREAFTER AS THE MIXING LAYER
DECOUPLES. LITTLE/NO BACKGROUND SUPPORT MAY FURTHER LIMIT THE
CHANCES OF THIS PERSISTING OVER THE REMAINDER OF THE SOUTH
PLAINS...BUT WILL KEEP SOME ISOLATED MENTION THROUGH 06Z.
SUNDAY WILL SEE IMPROVED W-SWLY FLOW OVERSPREAD THE REGION RESULTING
IN THE DRYLINE MIXING OUT OF NEW MEXICO AND STALLING SOMEWHERE OVER
THE WESTERN 1/3 OF THE CWA. ALBEIT MODEST...AN ADDITIONAL INFLUX OF
GULF MOISTURE BY EARLY SUNDAY IS PROGGED TO SECURE HIGHER SBCAPES
GENERALLY AROUND 3500 J/KG ALONG THE DRYLINE WITH EVEN EXTREME
VALUES IN THE ROLLING PLAINS...HOWEVER THE LATTER IS SHOWN TO REMAIN
CAPPED AND TOO FAR REMOVED FROM THE DRYLINE. NO DISCERNIBLE SHORT
WAVE TROUGHS ARE PROGGED...BUT AS IS THE CASE TODAY DEEP MIXING
SHOULD PROVE MORE THAN ADEQUATE FOR AT LEAST ISO TSTMS. WINDOW FOR
SUPERCELLS WILL BE OPENED 0-6KM BULK SHEAR VECTORS RISE TO NEARLY 40
KNOTS AND MAINTAIN A PERPENDICULAR ORIENTATION TO THE DRYLINE.
ROBUST CAPE IN THE HAIL GROWTH LAYER COMBINED WITH RELATIVELY HIGH
LCL VALUES WILL OPEN THE WINDOW FOR SOME VERY LARGE HAIL AND DMGG
DOWNBURSTS. MOST HIGH TEMPS WERE KEPT A FEW DEGREES ABOVE
MOS...PARTICULARLY WEST OF THE DRYLINE WHERE OUR HIGHEST ELEVATIONS
COULD END UP WITH THE HOTTEST VALUES FOR THE DAY.
LONG TERM...
HIGH AMPLITUDE RIDGE ORIENTED FROM THE BIG BEND TO THE WESTERN GREAT
LAKES THENCE WELL INTO CENTRAL CANADA WILL CONTINUE ITS SLOW
EASTWARD PROGRESSION AS A COUPLE OF STORM SYSTEMS COME ASHORE THE
PACIFIC NORTHWEST. TOWARD MID WEEK...FLOW ACROSS WEST TEXAS WILL
STRENGTHEN AS NEGATIVELY TILTED TROUGH DEEPENS FROM THE PAC NW.
THURSDAY SHOULD SEE A RETURN TO ZONAL FLOW AS UPPER LOW SETTLES
ACROSS WYOMING THOUGH ANOTHER LOBE OF ENERGY ROTATING AROUND THE WY
SYSTEM WILL APPROACH LATE THU/EARLY FRIDAY WITH SOUTHWESTERLIES
PERSISTING THROUGH DAY 7.
WILL CONTINUE MENTION OF TSRA INTO THE EVENING HOURS ON SUNDAY WITH
CONDITIONS SETTLING AFTER SUNSET. DRYLINE SHOULD PUSH INTO NEW
MEXICO OVERNIGHT THEN TIGHTEN UP AGAIN MONDAY AFTERNOON WITH
CONVECTION LOOKING MOST LIKELY EAST OF A SILVERTON TO BROWNFIELD
LINE THOUGH SOME VARIANCE WILL BE POSSIBLE GIVEN THE INFLUENCES OF
SUNDAY NIGHT/S STORMS. WEDNESDAY LOOKS TO KEEP THE DRYLINE A BIT
FURTHER WEST THUS GIVING MORE OF THE AREA A SHOT AT THE MUCH NEEDED
RAINFALL. WITH THE MORE STRONGLY DIFLUENT FLOW ON WEDNESDAY...THIS
COULD BE THE MOST PRONOUNCED OF THE SEVERE WEATHER THIS WEEK THOUGH
EACH DAY WILL HAVE SEVERE POTENTIAL. THE LONG AND SHORT OF IT IS
THAT EACH DAY OVER THE NEXT WEEK...WE WILL SEE AT LEAST SCATTERED
CONVECTION POTENTIAL EACH AFTERNOON AS THE DRYLINE SLOSHES ACROSS
THE REGION. AT PRESENT...IT WOULD APPEAR THE TORNADO THREAT THIS
WEEK WOULD BE MAXIMIZED ACROSS THE NORTHEASTERN ZONES ON WEDNESDAY.
TO THE WEST OF THE DRYLINE...ELEVATED TO LOW END CRITICAL FIRE
WEATHER CONDITIONS WILL EXIST NEARLY EVERY AFTERNOON AS MIN AFTN RH
DROPS TO THE LOWER TEENS WITH THE BREEZY WEST-OF-THE-DRYLINE WINDS.
OUR NORTHWEST HAS SEEN THE LOWEST AMOUNT OF GREEN-UP DUE TO THE LACK
OF PRECIPITATION THIS SPRING AND WHILE FUELS ARE NOT
PLENTIFUL...WHAT IS THERE WOULD BE EXPECTED TO BURN QUITE EASILY
GIVEN THE RIGHT METEOROLOGICAL CONDITIONS.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 61 94 62 94 61 / 20 20 20 10 10
TULIA 61 94 65 94 64 / 40 20 20 20 20
PLAINVIEW 62 93 65 95 65 / 20 20 20 20 20
LEVELLAND 63 95 68 95 67 / 50 20 20 20 20
LUBBOCK 65 94 67 95 67 / 40 20 20 20 20
DENVER CITY 62 95 68 95 68 / 30 10 10 10 20
BROWNFIELD 63 95 68 96 68 / 60 20 20 20 20
CHILDRESS 68 94 67 94 67 / 20 10 10 10 20
SPUR 65 92 68 95 68 / 20 10 10 10 20
ASPERMONT 68 93 69 92 69 / 10 10 10 10 20
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
23/33
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
722 PM CDT SAT MAY 25 2013
.UPDATE...
00Z FWD RAOB SHOWS THAT WE ARE ALREADY CAPPED AT THE SURFACE FOR
ADDITIONAL CONVECTION. LATEST AREA RADARS SHOW LITTLE ACTIVITY
WHICH IS LIKELY DUE TO THE CAPPING INVERSION. LOWERED THE 50 POPS
ACROSS THE SE TO 30 FOR THE REST OF THE NIGHT. LATEST HIGH-RES
GUIDANCE ALSO KEEPS THINGS RELATIVELY DRY FOR THE NIGHT...WITH
ONLY ISOLATED TO SCATTERED ACTIVITY FORECASTED.
WE DO ALSO HAVE TO WATCH CONVECTION WHICH IS DEVELOPING IN EASTERN
NEW MEXICO AS IT PROGRESSES EAST LATE THIS EVENING AND OVERNIGHT.
LATEST HRRR BRINGS THE WEAKENING STORMS NEAR OUR WESTERN ZONES
AFTER MIDNIGHT BEFORE DYING OFF. WILL KEEP THE 20 POPS ACROSS THE
WEST TO ACCOUNT FOR THIS POTENTIAL.
HAMPSHIRE
&&
.AVIATION...
SHOWERS AND THUNDERSTORMS BETWEEN KAFW AND KCRS WILL CONTINUE TO
MOVE NORTHEAST THIS EVENING. WILL LEAVE A TEMPO 6SM -SHRA IN
BETWEEN 00Z AND 01Z AT KDAL. VFR CONDITIONS ARE EXPECTED AT THE
AREA AIRPORTS FOR MOST OF THE OVERNIGHT PERIOD. SOME MVFR STRATUS
WILL SPREAD NORTH INTO THE WACO AREA AROUND 09Z...AND INTO THE
METROPLEX AROUND 11Z. THE LOW CLOUDS WILL SCATTER OUT AFTER 16Z
SUNDAY. SOUTH WINDS AROUND 10 KNOTS WILL INCREASE TO AROUND 15
KNOTS BY 16Z SUNDAY AND SOME GUSTS OVER 20 KNOTS ARE LIKELY
SUNDAY AFTERNOON.
58
&&
.PREV DISCUSSION... /ISSUED 414 PM CDT SAT MAY 25 2013/
THROUGH TONIGHT...LEFT THE EARLY AFTERNOON UPDATE FORECAST
DISCUSSION ATTACHED BELOW FOR REFERENCE AND MORE DETAILS ON THE
SHORT TERM FORECAST CONCERNS.
CHANGES FROM EARLIER DISCUSSION...THE MCV THAT WAS EXPECTED TO
DEVELOP NEAR SAN ANTONIO WAS APPARENT IN REGIONAL RADAR RETURNS
NEAR AUSTIN AND GONZALEZ AT THE TIME OF THIS DISCUSSION. ASSUMING
THAT THIS IS THE PRIMARY MID-LEVEL LOW/MCV PRODUCED BY THE
PERSISTENT SAN ANTONIO AREA CONVECTION THIS MORNING...ADJUSTED
RAIN CHANCES THIS EVENING AND OVERNIGHT IN LINE WITH ITS EXPECTED
TRAJECTORY. THE 19Z RUN OF THE RAP SEEMS TO HAVE A GOOD HANDLE ON
THE POSITION OF THIS MCV...SO GENERALLY USED THIS MODEL FOR
GUIDANCE OVER THE NEXT 12 TO 18 HRS.
THE MCV IS EXPECTED TO MOVE GENERALLY IN A NORTHEASTERLY DIRECTION
THROUGH TONIGHT...TAKING IT FROM ITS CURRENT LOCATION TO JUST
NORTHEAST OF TYLER BY SUNRISE SUNDAY. THE GFS INDICATES THAT THE
UPPER TROUGH THAT WAS ANALYZED IN THE 12Z RAOB ANALYSIS TO THE
WEST OF THE CWA WILL INTERACT WITH THIS MCV FAVORABLY AND RESULT
IN WIDESPREAD THUNDERSTORM ACTIVITY GENERALLY EAST OF I-35 AND
SOUTH OF I-20 AFTER MIDNIGHT...SPREADING NORTHEAST INTO THE
ARKLATEX AREA JUST AFTER SUNRISE. BOTH OF THESE FEATURES
EXIST...SO THIS SOLUTION IS VIABLE...HOWEVER THE FORCING FOR
ASCENT ADVERTISED BY THE GFS IS GREATLY ENHANCED BY CONVECTIVE
FEEDBACK. THAT IS...MODEL GENERATED STORMS COOL OFF LOCATIONS
DOWNSTREAM /NORTHEAST/ ALLOWING WARM AIR ADVECTION TO ARTIFICIALLY
RAMP UP RESULTING IN THE GENERATION OF MORE STORMS. IN SHORT...A
MODEL GENERATED FEEDBACK LOOP. THIS LOOP MAY VERIFY AND RESULT IN
A HEAVY RAINFALL EVENT EAST OF I-35 TO THE ARKLATEX AREA TONIGHT
THROUGH SUNDAY MORNING. HOWEVER THERE IS NOT REALLY ANY HIGH
RESOLUTION MODEL OUTPUT SUPPORT FOR THIS SOLUTION AT THIS
TIME...THEREFORE CONFIDENCE IS SOMEWHAT LOW IN A WIDESPREAD HEAVY
RAIN EVENT.
THAT SAID...MANY FACTORS ARE IN PLACE TO SUPPORT A LOCALIZED HEAVY
RAINFALL EVENT ANYWHERE STORMS EXIST OVER THE NEXT 12 TO 18 HRS.
PRECIPITABLE WATER VALUES ARE ABOVE THE 75TH PERCENTILE OF
HISTORICAL PRECIPITABLE WATER VALUES FOR THIS REGION IN LATE MAY.
MID-LEVEL LAPSE RATES ARE POOR BUT THE ENVIRONMENT IS
UNCAPPED...IN SHORT A FAVORABLE ENVIRONMENT FOR VERY TALL RAIN
SHOWERS WITH LITTLE LIGHTNING ACTIVITY AND ONLY WEAK GENERATION OF
OUTFLOW BOUNDARIES. WEAK OUTFLOW MEANS THAT STORMS CAN REMAIN IN
ONE PLACE FOR A LONGER PERIOD OF TIME INCREASING THE CHANCES FOR
TRAINING OF STORMS AND A LOCALIZED FLOODING THREAT. AT THIS TIME
WENT WITH A MENTION OF LOCALIZED HEAVY RAIN AND FLOODING IN THE
HAZARDOUS WEATHER OUTLOOK AND WORDED FORECAST.
WITH WEAK WIND SHEAR IN THIS THERMODYNAMIC ENVIRONMENT STORMS ARE
EXPECTED TO BEHAVE IN A NEARLY TROPICAL NATURE WITH EFFICIENT
RAINFALL PRODUCTION. THEREFORE CHANCES OF SEVERE WEATHER APPEAR TO
BE VERY SMALL TONIGHT. WE WILL HAVE TO KEEP A CLOSE EYE ON THE
EVOLUTION OF A LOCALIZED FLOODING EVENT...ESPECIALLY WITH MANY
PEOPLE LIKELY CAMPING OUTDOORS IN FLOOD PRONE AREAS THROUGH
TONIGHT.
SUNDAY...SUNDAY MORNING WE WILL LIKELY HAVE SOME REMNANT POCKETS
OF HEAVY RAIN ALONG A SULPHUR SPRINGS TO PALESTINE LINE...LIKELY
MOVING NORTHEAST TOWARDS THE ARKLATEX REGION THROUGHOUT THE
MORNING HOURS. FROM THE WEST...THE HRRR HAS CONSISTENTLY INDICATED
THAT A SQUALL LINE WILL ORGANIZE OVER THE SOUTHERN HIGH PLAINS/TX
PANHANDLE TONIGHT AND MOVE EAST TOWARDS OUR WESTERN CWA EARLY
SUNDAY MORNING. WE WILL HAVE TO KEEP AN EYE ON THIS...NOT SO MUCH
FROM A SEVERE WEATHER STAND POINT BUT FROM ANOTHER POTENTIAL
SOURCE FOR MCV PRODUCTION. WITH THE SAN ANTONIO AREA MCV AND
LARGER UPPER TROUGH MOVING EAST...SUBSIDENCE WILL LIKELY DOMINATE
ANY MCV MOVING OFF THE HIGH PLAINS AND THRU NORTH TX TOMORROW.
HOWEVER UNTIL WE GET SOME DRIER AIR IN OVER THE REGION CAPPING OFF
THE ATMOSPHERE FOR THUNDERSTORM DEVELOPMENT...WILL HOLD ON TO A
BROAD BRUSHED MENTION OF SHOWERS AND THUNDERSTORMS IN THE FORECAST
ACROSS ALL OF NORTH TX THROUGH SUNDAY.
NEXT WEEK...BEGINNING MONDAY A WESTERN CONUS TROUGH IS EXPECTED TO
ORGANIZE SENDING THE WEAK UPPER LEVEL RIDGE AND ENTRAPPED MCV
FEATURES OFF TO THE EAST OF THE REGION. THIS IS EXPECTED TO RESULT
IN SOUTHWEST FLOW ALOFT OVER NORTH TX ON MONDAY WHICH SHOULD HELP
TO ADVECT A RELATIVELY STOUT CAP IN PLACE OVER THE REGION BY
MONDAY AFTERNOON. THIS CAP IS EXPECTED TO HOLD IN PLACE THROUGH
THE WEEK UNLESS THE DRYLINE OR A STRONG SHORTWAVE TROUGH CAN LIFT
THE CAP AND RESULT IN THUNDERSTORM INITIATION DURING THE WEEK
AHEAD.
WE ARE EXPECTED TO HAVE RELATIVELY PERSISTENT...BREEZY SOUTH
WINDS IN PLACE BELOW THE CAP THROUGH THE WEEK. THIS WILL HELP KEEP
GOOD GULF MOISTURE IN PLACE UNDER THE CAP PROVIDING PLENTY OF
POSITIVE CAPE FOR THUNDERSTORM DEVELOPMENT IF ANYTHING CAN REMOVE
THE CAP. WITHOUT STORMS...WE WILL LIKELY SEE HIGHS HOLD IN THE
UPPER 80S WITH LOWS IN THE LOWER TO MID 70S EACH DAY. THE GFS AND
ECMWF BOTH INDICATE THAT A STRONG SHORTWAVE TROUGH WILL MOVE OVER
THE SOUTH PLAINS WEDNESDAY THROUGH WEDNESDAY EVENING. THE ECMWF
REMAINS FURTHER SOUTH WITH THIS TROUGH WHICH IS WHAT WE WILL NEED
TO LIFT THE CAP AND RESULT IN STORMS ACROSS THE CWA WEDNESDAY
AFTERNOON AND EVENING. THE GFS INDICATES THE BEST FORCING STAYS
NORTH OF THE CWA. WENT AHEAD WITH 20 TO 30 POPS WEST OF INTERSTATE
35...CLOSEST TO THE UPPER TROUGH WEDNESDAY AFTERNOON THROUGH
WEDNESDAY NIGHT AS RESULT. REMOVED POPS THEREAFTER WITH ALL
GUIDANCE INDICATING SUBSIDENCE BEHIND THIS UPPER TROUGH ON
THURSDAY.
CAVANAUGH
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 69 84 67 86 69 / 30 20 10 0 0
WACO, TX 68 86 67 88 69 / 30 20 10 0 0
PARIS, TX 68 82 65 84 67 / 30 30 10 0 0
DENTON, TX 67 83 66 85 68 / 30 20 10 0 0
MCKINNEY, TX 68 82 66 86 68 / 30 20 10 0 0
DALLAS, TX 71 83 70 88 72 / 30 20 10 0 0
TERRELL, TX 70 82 67 87 69 / 30 30 10 0 0
CORSICANA, TX 69 83 68 88 69 / 30 20 10 0 0
TEMPLE, TX 68 85 67 87 69 / 30 20 10 0 0
MINERAL WELLS, TX 67 86 66 87 68 / 20 20 10 0 5
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
85/85
AREA FORECAST DISCUSSION...UPDATED
NWS LUBBOCK TX
652 PM CDT SAT MAY 25 2013
.UPDATE...
QUICK UPDATE TO INCREASE POPS ACROSS THE FAR WESTERN COUNTIES THIS
EVENING...PARTICULARLY THE NORTHWESTERN MOST ZONES...WHERE
STRONG/SEVERE CONVECTION IS POISED TO MOVE IN. HAIL AND WIND
THREAT MAY PERSIST FOR A COUPLE OF HOURS AS STORMS MOVE INTO
STRONG INSTABILITY...THOUGH EXPECT A GRADUALLY WEAKENING TREND
AFTER SUNSET. STILL...GUSTY /AND DUSTY/ OUTFLOW COULD ORGANIZE AND
MAKE A PUSH EASTWARD ACROSS THE CAPROCK. UPDATED PRODUCTS HAVE
BEEN SENT.
&&
.PREV DISCUSSION... /ISSUED 631 PM CDT SAT MAY 25 2013/
AVIATION...
AVIATION CONCERNS ARE -TSRA AND/OR STRONG OUTFLOW BOUNDARY AT KLBB
LATE THIS EVENING...AND MVFR CEILINGS AT KCDS EARLY SUNDAY
MORNING. T-STORMS IN EASTERN NM WILL GRADUALLY MOVE EAST THIS
EVENING...BUT WILL LIKELY DECAY BEFORE REACHING KLBB. THE PASSAGE
OF AN OUTFLOW BOUNDARY IS CONSIDERED MORE LIKELY AT THIS
TIME. WE HAVE VERY LOW CONFIDENCE IN WIND SPEEDS ASSOC. WITH ANY
BOUNDARY...SO WE HAVE KEPT THEM ON THE CONSERVATIVE SIDE IN A
TEMPO MENTION. AT KCDS...WE EXPECT LOW STRATUS TO MOVE IN AROUND
10 UTC...THEN GRADUALLY SCOUR OUT SUN MORN. VFR CONDITIONS ARE
EXPECTED AREA-WIDE BY MIDDAY...WITH WIDELY SCATTERED CB DEVELOPING
BY MID TO LATE AFTERNOON.
PREV DISCUSSION... /ISSUED 339 PM CDT SAT MAY 25 2013/
SHORT TERM...
MOIST UPSLOPE FLOW ACROSS EASTERN NEW MEXICO HAS ALREADY SUPPORTED
SCATTERED TSTMS FROM THE SACRAMENTOS NORTH TO SANTA ROSA. A SECOND
AREA OF INTEREST IS EVIDENT ON VIS SATELLITE ALONG THE MESCALERO
ESCARPMENT WHERE AGITATED CU HAVE RECENTLY DEVELOPED. HRRR AND
NAM-WRF BOTH PROG TSTM DEVELOPMENT ALONG THIS CU LINE BEFORE 00Z
AND CARRY IT EASTWARD TO VARIOUS DEGREES WITHIN 20 KNOTS OF
700-500MB FLOW. CONSIDERING CINH IS TRENDING NEGLIGIBLE ALONG THE
NM/TX STATE LINE AND SBCAPE IS AROUND 2K J/KG...HAVE ADDED SEVERE
MENTION TO OUR WESTERNMOST COUNTIES WHERE THIS ACTIVITY WILL LIKELY
PEAK IN INTENSITY BEFORE DIMINISHING THEREAFTER AS THE MIXING LAYER
DECOUPLES. LITTLE/NO BACKGROUND SUPPORT MAY FURTHER LIMIT THE
CHANCES OF THIS PERSISTING OVER THE REMAINDER OF THE SOUTH
PLAINS...BUT WILL KEEP SOME ISOLATED MENTION THROUGH 06Z.
SUNDAY WILL SEE IMPROVED W-SWLY FLOW OVERSPREAD THE REGION RESULTING
IN THE DRYLINE MIXING OUT OF NEW MEXICO AND STALLING SOMEWHERE OVER
THE WESTERN 1/3 OF THE CWA. ALBEIT MODEST...AN ADDITIONAL INFLUX OF
GULF MOISTURE BY EARLY SUNDAY IS PROGGED TO SECURE HIGHER SBCAPES
GENERALLY AROUND 3500 J/KG ALONG THE DRYLINE WITH EVEN EXTREME
VALUES IN THE ROLLING PLAINS...HOWEVER THE LATTER IS SHOWN TO REMAIN
CAPPED AND TOO FAR REMOVED FROM THE DRYLINE. NO DISCERNIBLE SHORT
WAVE TROUGHS ARE PROGGED...BUT AS IS THE CASE TODAY DEEP MIXING
SHOULD PROVE MORE THAN ADEQUATE FOR AT LEAST ISO TSTMS. WINDOW FOR
SUPERCELLS WILL BE OPENED 0-6KM BULK SHEAR VECTORS RISE TO NEARLY 40
KNOTS AND MAINTAIN A PERPENDICULAR ORIENTATION TO THE DRYLINE.
ROBUST CAPE IN THE HAIL GROWTH LAYER COMBINED WITH RELATIVELY HIGH
LCL VALUES WILL OPEN THE WINDOW FOR SOME VERY LARGE HAIL AND DMGG
DOWNBURSTS. MOST HIGH TEMPS WERE KEPT A FEW DEGREES ABOVE
MOS...PARTICULARLY WEST OF THE DRYLINE WHERE OUR HIGHEST ELEVATIONS
COULD END UP WITH THE HOTTEST VALUES FOR THE DAY.
LONG TERM...
HIGH AMPLITUDE RIDGE ORIENTED FROM THE BIG BEND TO THE WESTERN GREAT
LAKES THENCE WELL INTO CENTRAL CANADA WILL CONTINUE ITS SLOW
EASTWARD PROGRESSION AS A COUPLE OF STORM SYSTEMS COME ASHORE THE
PACIFIC NORTHWEST. TOWARD MID WEEK...FLOW ACROSS WEST TEXAS WILL
STRENGTHEN AS NEGATIVELY TILTED TROUGH DEEPENS FROM THE PAC NW.
THURSDAY SHOULD SEE A RETURN TO ZONAL FLOW AS UPPER LOW SETTLES
ACROSS WYOMING THOUGH ANOTHER LOBE OF ENERGY ROTATING AROUND THE WY
SYSTEM WILL APPROACH LATE THU/EARLY FRIDAY WITH SOUTHWESTERLIES
PERSISTING THROUGH DAY 7.
WILL CONTINUE MENTION OF TSRA INTO THE EVENING HOURS ON SUNDAY WITH
CONDITIONS SETTLING AFTER SUNSET. DRYLINE SHOULD PUSH INTO NEW
MEXICO OVERNIGHT THEN TIGHTEN UP AGAIN MONDAY AFTERNOON WITH
CONVECTION LOOKING MOST LIKELY EAST OF A SILVERTON TO BROWNFIELD
LINE THOUGH SOME VARIANCE WILL BE POSSIBLE GIVEN THE INFLUENCES OF
SUNDAY NIGHT/S STORMS. WEDNESDAY LOOKS TO KEEP THE DRYLINE A BIT
FURTHER WEST THUS GIVING MORE OF THE AREA A SHOT AT THE MUCH NEEDED
RAINFALL. WITH THE MORE STRONGLY DIFLUENT FLOW ON WEDNESDAY...THIS
COULD BE THE MOST PRONOUNCED OF THE SEVERE WEATHER THIS WEEK THOUGH
EACH DAY WILL HAVE SEVERE POTENTIAL. THE LONG AND SHORT OF IT IS
THAT EACH DAY OVER THE NEXT WEEK...WE WILL SEE AT LEAST SCATTERED
CONVECTION POTENTIAL EACH AFTERNOON AS THE DRYLINE SLOSHES ACROSS
THE REGION. AT PRESENT...IT WOULD APPEAR THE TORNADO THREAT THIS
WEEK WOULD BE MAXIMIZED ACROSS THE NORTHEASTERN ZONES ON WEDNESDAY.
TO THE WEST OF THE DRYLINE...ELEVATED TO LOW END CRITICAL FIRE
WEATHER CONDITIONS WILL EXIST NEARLY EVERY AFTERNOON AS MIN AFTN RH
DROPS TO THE LOWER TEENS WITH THE BREEZY WEST-OF-THE-DRYLINE WINDS.
OUR NORTHWEST HAS SEEN THE LOWEST AMOUNT OF GREEN-UP DUE TO THE LACK
OF PRECIPITATION THIS SPRING AND WHILE FUELS ARE NOT
PLENTIFUL...WHAT IS THERE WOULD BE EXPECTED TO BURN QUITE EASILY
GIVEN THE RIGHT METEOROLOGICAL CONDITIONS.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 61 94 62 94 61 / 50 20 20 10 10
TULIA 61 94 65 94 64 / 20 20 20 20 20
PLAINVIEW 62 93 65 95 65 / 20 20 20 20 20
LEVELLAND 63 95 68 95 67 / 20 20 20 20 20
LUBBOCK 65 94 67 95 67 / 20 20 20 20 20
DENVER CITY 62 95 68 95 68 / 30 10 10 10 20
BROWNFIELD 63 95 68 96 68 / 20 20 20 20 20
CHILDRESS 68 94 67 94 67 / 10 10 10 10 20
SPUR 65 92 68 95 68 / 10 10 10 10 20
ASPERMONT 68 93 69 92 69 / 10 10 10 10 20
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
33/23
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
631 PM CDT SAT MAY 25 2013
.AVIATION...
AVIATION CONCERNS ARE -TSRA AND/OR STRONG OUTFLOW BOUNDARY AT KLBB
LATE THIS EVENING...AND MVFR CEILINGS AT KCDS EARLY SUNDAY
MORNING. T-STORMS IN EASTERN NM WILL GRADUALLY MOVE EAST THIS
EVENING...BUT WILL LIKELY DECAY BEFORE REACHING KLBB. THE PASSAGE
OF AN OUTFLOW BOUNDARY IS CONSIDERED MORE LIKELY AT THIS
TIME. WE HAVE VERY LOW CONFIDENCE IN WIND SPEEDS ASSOC. WITH ANY
BOUNDARY...SO WE HAVE KEPT THEM ON THE CONSERVATIVE SIDE IN A
TEMPO MENTION. AT KCDS...WE EXPECT LOW STRATUS TO MOVE IN AROUND
10 UTC...THEN GRADUALLY SCOUR OUT SUN MORN. VFR CONDITIONS ARE
EXPECTED AREA-WIDE BY MIDDAY...WITH WIDELY SCATTERED CB DEVELOPING
BY MID TO LATE AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 339 PM CDT SAT MAY 25 2013/
SHORT TERM...
MOIST UPSLOPE FLOW ACROSS EASTERN NEW MEXICO HAS ALREADY SUPPORTED
SCATTERED TSTMS FROM THE SACRAMENTOS NORTH TO SANTA ROSA. A SECOND
AREA OF INTEREST IS EVIDENT ON VIS SATELLITE ALONG THE MESCALERO
ESCARPMENT WHERE AGITATED CU HAVE RECENTLY DEVELOPED. HRRR AND
NAM-WRF BOTH PROG TSTM DEVELOPMENT ALONG THIS CU LINE BEFORE 00Z
AND CARRY IT EASTWARD TO VARIOUS DEGREES WITHIN 20 KNOTS OF
700-500MB FLOW. CONSIDERING CINH IS TRENDING NEGLIGIBLE ALONG THE
NM/TX STATE LINE AND SBCAPE IS AROUND 2K J/KG...HAVE ADDED SEVERE
MENTION TO OUR WESTERNMOST COUNTIES WHERE THIS ACTIVITY WILL LIKELY
PEAK IN INTENSITY BEFORE DIMINISHING THEREAFTER AS THE MIXING LAYER
DECOUPLES. LITTLE/NO BACKGROUND SUPPORT MAY FURTHER LIMIT THE
CHANCES OF THIS PERSISTING OVER THE REMAINDER OF THE SOUTH
PLAINS...BUT WILL KEEP SOME ISOLATED MENTION THROUGH 06Z.
SUNDAY WILL SEE IMPROVED W-SWLY FLOW OVERSPREAD THE REGION RESULTING
IN THE DRYLINE MIXING OUT OF NEW MEXICO AND STALLING SOMEWHERE OVER
THE WESTERN 1/3 OF THE CWA. ALBEIT MODEST...AN ADDITIONAL INFLUX OF
GULF MOISTURE BY EARLY SUNDAY IS PROGGED TO SECURE HIGHER SBCAPES
GENERALLY AROUND 3500 J/KG ALONG THE DRYLINE WITH EVEN EXTREME
VALUES IN THE ROLLING PLAINS...HOWEVER THE LATTER IS SHOWN TO REMAIN
CAPPED AND TOO FAR REMOVED FROM THE DRYLINE. NO DISCERNIBLE SHORT
WAVE TROUGHS ARE PROGGED...BUT AS IS THE CASE TODAY DEEP MIXING
SHOULD PROVE MORE THAN ADEQUATE FOR AT LEAST ISO TSTMS. WINDOW FOR
SUPERCELLS WILL BE OPENED 0-6KM BULK SHEAR VECTORS RISE TO NEARLY 40
KNOTS AND MAINTAIN A PERPENDICULAR ORIENTATION TO THE DRYLINE.
ROBUST CAPE IN THE HAIL GROWTH LAYER COMBINED WITH RELATIVELY HIGH
LCL VALUES WILL OPEN THE WINDOW FOR SOME VERY LARGE HAIL AND DMGG
DOWNBURSTS. MOST HIGH TEMPS WERE KEPT A FEW DEGREES ABOVE
MOS...PARTICULARLY WEST OF THE DRYLINE WHERE OUR HIGHEST ELEVATIONS
COULD END UP WITH THE HOTTEST VALUES FOR THE DAY.
LONG TERM...
HIGH AMPLITUDE RIDGE ORIENTED FROM THE BIG BEND TO THE WESTERN GREAT
LAKES THENCE WELL INTO CENTRAL CANADA WILL CONTINUE ITS SLOW
EASTWARD PROGRESSION AS A COUPLE OF STORM SYSTEMS COME ASHORE THE
PACIFIC NORTHWEST. TOWARD MID WEEK...FLOW ACROSS WEST TEXAS WILL
STRENGTHEN AS NEGATIVELY TILTED TROUGH DEEPENS FROM THE PAC NW.
THURSDAY SHOULD SEE A RETURN TO ZONAL FLOW AS UPPER LOW SETTLES
ACROSS WYOMING THOUGH ANOTHER LOBE OF ENERGY ROTATING AROUND THE WY
SYSTEM WILL APPROACH LATE THU/EARLY FRIDAY WITH SOUTHWESTERLIES
PERSISTING THROUGH DAY 7.
WILL CONTINUE MENTION OF TSRA INTO THE EVENING HOURS ON SUNDAY WITH
CONDITIONS SETTLING AFTER SUNSET. DRYLINE SHOULD PUSH INTO NEW
MEXICO OVERNIGHT THEN TIGHTEN UP AGAIN MONDAY AFTERNOON WITH
CONVECTION LOOKING MOST LIKELY EAST OF A SILVERTON TO BROWNFIELD
LINE THOUGH SOME VARIANCE WILL BE POSSIBLE GIVEN THE INFLUENCES OF
SUNDAY NIGHT/S STORMS. WEDNESDAY LOOKS TO KEEP THE DRYLINE A BIT
FURTHER WEST THUS GIVING MORE OF THE AREA A SHOT AT THE MUCH NEEDED
RAINFALL. WITH THE MORE STRONGLY DIFLUENT FLOW ON WEDNESDAY...THIS
COULD BE THE MOST PRONOUNCED OF THE SEVERE WEATHER THIS WEEK THOUGH
EACH DAY WILL HAVE SEVERE POTENTIAL. THE LONG AND SHORT OF IT IS
THAT EACH DAY OVER THE NEXT WEEK...WE WILL SEE AT LEAST SCATTERED
CONVECTION POTENTIAL EACH AFTERNOON AS THE DRYLINE SLOSHES ACROSS
THE REGION. AT PRESENT...IT WOULD APPEAR THE TORNADO THREAT THIS
WEEK WOULD BE MAXIMIZED ACROSS THE NORTHEASTERN ZONES ON WEDNESDAY.
TO THE WEST OF THE DRYLINE...ELEVATED TO LOW END CRITICAL FIRE
WEATHER CONDITIONS WILL EXIST NEARLY EVERY AFTERNOON AS MIN AFTN RH
DROPS TO THE LOWER TEENS WITH THE BREEZY WEST-OF-THE-DRYLINE WINDS.
OUR NORTHWEST HAS SEEN THE LOWEST AMOUNT OF GREEN-UP DUE TO THE LACK
OF PRECIPITATION THIS SPRING AND WHILE FUELS ARE NOT
PLENTIFUL...WHAT IS THERE WOULD BE EXPECTED TO BURN QUITE EASILY
GIVEN THE RIGHT METEOROLOGICAL CONDITIONS.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 61 94 62 94 61 / 30 20 20 10 10
TULIA 61 94 65 94 64 / 20 20 20 20 20
PLAINVIEW 62 93 65 95 65 / 20 20 20 20 20
LEVELLAND 63 95 68 95 67 / 20 20 20 20 20
LUBBOCK 65 94 67 95 67 / 20 20 20 20 20
DENVER CITY 62 95 68 95 68 / 20 10 10 10 20
BROWNFIELD 63 95 68 96 68 / 20 20 20 20 20
CHILDRESS 68 94 67 94 67 / 10 10 10 10 20
SPUR 65 92 68 95 68 / 10 10 10 10 20
ASPERMONT 68 93 69 92 69 / 10 10 10 10 20
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
33
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
630 PM CDT SAT MAY 25 2013
.DISCUSSION...
EXPECT STRATUS TO BRING MVFR CEILINGS BACK TO WEST CENTRAL TEXAS
DURING THE NEXT 6 HOURS. AVIATION BELOW HAS DETAILS.
&&
.AVIATION...
MODELS DATA INDICATE STRATUS WILL RETURN TO WEST CENTRAL TEXAS
TONIGHT AND PERSIST UNTIL AROUND NOON TOMORROW. THE LATEST RUC 925
MB RELATIVE HUMIDITY AND WIND FIELD DATA INDICATE STRATUS WILL
RETURN TO WEST CENTRAL TEXAS...FROM THE EAST AND
SOUTHEAST...BEGINNING AROUND 03Z. BY 06Z TONIGHT...PLAN FOR MVFR
CEILINGS TO DOMINATE WEST CENTRAL TEXAS. MOS GUIDANCE DATA FROM
THE GFS INDICATE MVFR CEILINGS AROUND 1500 FEET ABOVE GROUND LEVEL
AT ALL 5 TERMINALS. THE NAM BASED GUIDANCE IS MORE AGGRESSIVE AND
PREDICTS IFR CEILINGS AROUND 700 FEET ABOVE GROUND LEVEL. I
DECIDED TO CONTINUE WITH A FORECAST FAVORING THE GFS
SOLUTION...MAINLY BASED ON PERSISTENCE. AS WAS THE CASE
TODAY...LOOK FOR VFR CEILINGS TO RETURN TO WEST CENTRAL TEXAS
AROUND NOON TOMORROW.
HUBER
&&
.PREV DISCUSSION... /ISSUED 501 PM CDT SAT MAY 25 2013/
UPDATE...
FORECAST IS BEING UPDATED FOR POPS...QPF AND SKY CONDITION. SEE
DISCUSSION.
DISCUSSION...
SCATTERED SHOWERS WHICH WERE OVER THE EASTERN THIRD OF WEST CENTRAL
TEXAS EARLIER TODAY HAVE SINCE MOVED OUT OF THE AREA OR DISSIPATED.
RADAR LATE THIS AFTERNOON SHOWS NO ADDITIONAL SHOWER OR THUNDERSTORM
DEVELOPMENT...BUT A SLIGHT CHANCE REMAINS GIVEN THE MOIST AND
UNSTABLE AIRMASS STILL IN PLACE. WITH THE UPPER TROUGH AXIS MOVING
FARTHER AWAY FROM OUR AREA AND ACROSS EAST TEXAS...AND WITH THE
CONVECTIVE ACTIVITY DIURNALLY DRIVEN...EXPECT THE RAIN CHANCE IN
WEST CENTRAL TEXAS TO END BY OR BEFORE 9 PM. HAVE ADJUSTED THE
21Z-00Z WEATHER GRID TO REFLECT THE AFOREMENTIONED TRENDS...AND HAVE
ENDED THE RAIN CHANCE AFTER 02Z. THE GFS AND NAM BOTH SUGGEST LOW
CLOUD DEVELOPMENT NORTHWEST INTO OUR AREA LATE TONIGHT AND EARLY
SUNDAY MORNING...IN MOIST SOUTHEASTERLY BOUNDARY LAYER FLOW. HAVE
ADJUSTED THE SKY CONDITION GRIDS TO REFLECT THIS SCENARIO WITH
INCREASING CLOUDINESS TOWARD MORNING...TO ROUGHLY THE INTERSTATE 20
CORRIDOR. EXPECT THE LOW CLOUD FIELD TO ERODE BY MID TO LATE SUNDAY
MORNING. HAVE ALSO MADE DOWNWARD ADJUSTMENTS TO THE QPF GRIDS FROM
21Z-00Z. WITH LOW CONFIDENCE IN MEASURABLE PRECIPITATION OCCURRING
TONIGHT...HAVE DROPPED THE QPF GRIDS TO ZERO. UPDATED FORECAST
PRODUCTS WILL BE OUT SHORTLY.
PREV DISCUSSION... /ISSUED 341 PM CDT SAT MAY 25 2013/
SHORT TERM...
EARLY THIS AFTERNOON...UPPER TROUGH AXIS IS LOCATED JUST EAST OF
THE FORECAST AREA WITH ASSOCIATED RAINFALL AND THUNDERSTORMS
OCCURRING FROM THE CENTRAL TEXAS GULF COAST NORTH OVER MUCH OF
EAST TEXAS. WITH THE CLOSE PROXIMITY OF THE UPPER LOW TO OUR
CWA...WILL MAINTAIN A SLIGHT CHANCE OF SHOWERS AND ISOLATED
THUNDERSTORMS THROUGH THE NIGHT. AS THE UPPER TROUGH CONTINUES TO
MOVE EAST DURING THE DAY TOMORROW...AN UPPER RIDGE WILL BUILD OVER
THE OUR AREA FROM THE WEST...BRINGING AN END TO OUR RAINFALL
CHANCES. AFTER SUNDAY MORNING LOWS GENERALLY IN THE MID 60S...
AFTERNOON HIGHS ON SUNDAY WILL BE WARMER THAN TODAY...LOWER 90S VS
LOW TO MID 80S.
15
LONG TERM...
THE LONG TERM PORTION OF THE FORECAST WILL BE HIGHLIGHTED BY
PERSISTENT STRONG SOUTHERLY FLOW...OVERNIGHT AND MORNING
STRATUS...AND MIDWEEK PRECIPITATION CHANCES.
THE WEST COAST TROUGH IS PROGGED TO DEEPEN EARLY NEXT WEEK AS THE
SHORTWAVE TROUGH CURRENTLY LOCATED SOUTH OF THE ALEUTIANS MOVES
INTO THE PACNW. WE WILL SEE INCREASING SOUTHWEST FLOW ALOFT WHICH
WILL BOTH ENHANCE THE ELEVATED MIX LAYER /EML/ AND SUPPORT LEE
CYCLOGENESIS. THE LATTER WILL PROVIDE BRISK SOUTH WINDS THROUGHOUT
THE DURATION OF THE FORECAST PERIOD...WITH DAYTIME WIND SPEEDS OF
15-25 MPH AREAWIDE. A STRONG NOCTURNAL LOW LEVEL JET WILL KEEP
GUSTS IN THE FORECAST DURING THE OVERNIGHT HOURS WITH THE
STRONGEST WINDS FOUND ACROSS THE CONCHO VALLEY AND BIG COUNTRY.
THESE SOUTH WINDS WILL PROVIDE A STEADY STREAM OF GULF MOISTURE
INTO THE AREA...KEEPING DEWPOINTS GENERALLY IN THE LOWER 60S AND
PUSHING OVERNIGHT LOWS INTO THE UPPER 60S AND LOWER 70S THROUGH
THE WEEK. THESE BREEZY CONDITIONS MAY BE TEMPORARILY INTERRUPTED
BY CONVECTIVE OUTFLOW BUT I WILL GET MORE INTO THAT IN A BIT.
I EXPECT DRY CONDITIONS THROUGH MONDAY...ALTHOUGH SOME DIURNAL
CONVECTION TO OUR WEST MAY TRY TO SNEAK INTO THE WESTERN ZONES
MONDAY EVENING. THAT SAID...THE STEERING FLOW WILL KEEP THE BEST
CHANCES TO OUR NORTH AND WEST. OTHERWISE...THE CAP LOOKS TO HOLD
AND KEEP A LID ON THE CONVECTIVE POTENTIAL. TEMPS ON MONDAY ARE
EXPECTED TO RANGE FROM THE UPPER 80S TO LOWER 90S ACROSS MOST OF
WEST CENTRAL TX.
PRECIPITATION STILL DO NOT LOOK ALL THAT PROMISING ON TUESDAY DUE
TO THE STRENGTH OF THE EML. THAT SAID...I DID INCLUDE A SLIGHT
CHANCE OF THUNDERSTORMS GENERALLY WEST OF A SONORA...TO WINTERS...
TO HASKELL LINE TO ACCOUNT FOR THE EASTWARD DRIFT ON CONVECTION
OVER WEST TX. THE BEST RAIN CHANCES APPEAR TO OCCUR ON WEDNESDAY.
THE MEDIUM RANGE GUIDANCE IS DEPICTING A NEGATIVELY TILTED
SHORTWAVE TROUGH EJECTING INTO THE SOUTHERN PLAINS BY WEDNESDAY
AFTERNOON. THEY DO DIFFER IN THE LOCATION OF THE STRONGEST
FORCING...WITH THE GFS FAVORING THE CENTRAL HIGH PLAINS AND THE
ECMWF LOOKING FARTHER SOUTH TOWARD WEST TX. EITHER WAY...SYNOPTIC
SCALE FORCING WILL WORK ON THE EML...LIFTING AND COOLING THE LAYER
TO ERODE THE CAP. THE BIGGEST QUESTION IS HOW FAR SOUTH THIS
ASCENT REACHES. THE SEVERE POTENTIAL WILL EXIST GIVEN THE STEEP
MID LEVEL LAPSE RATES...STRONG INSTABILITY AND MORE THAN ADEQUATE
DEEP LAYER SHEAR. THE BIG QUESTION /AS IS USUALLY THE CASE/ IS THE
CAP.
THUNDERSTORM CHANCES LINGER ON THURSDAY BUT THE STRONGEST FORCING
LOOKS TO MOVE EAST BY THURSDAY. MODEL CONSENSUS SHOWS A DEEP...
BROAD TROUGH OVER THE WESTERN 2/3 OF THE CONUS WITH STRONG WEST
SOUTHWEST FLOW OVER WEST TX. WE MAY BEGIN TO SEE THE DRYLINE DRY
TO MIX EAST LATE IN THE PERIOD BUT THE EML LOOKS TO TAKE OVER WITH
THE CAP STRENGTHENING AND TEMPS WARMING BACK INTO THE LOW/MID 90S.
WE COULD BE LOOKING AT A PATTERN CHANCE BY THE LATTER HALF OF THE
WEEKEND WITH THE DEEP WESTERN TROUGH BEING REPLACED BY A SPLIT
FLOW REGIME.
JOHNSON
&&
.PRELIMINARY POINT TEMPS/POPS...
ABILENE 68 91 69 91 68 / 20 10 5 5 10
SAN ANGELO 68 91 69 92 70 / 20 10 5 5 10
JUNCTION 66 91 69 88 71 / 20 10 5 5 5
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
HUBER
AREA FORECAST DISCUSSION
NWS CORPUS CHRISTI TX
332 PM CDT FRI MAY 24 2013
.SHORT TERM (TONIGHT)...THIS MORNINGS SOUTHERN MCV ASSISTED IN
THE DEVELOPMENT OF A LINE OF SHOWERS AND THUNDERSTORMS ACROSS THE
WESTERN BRUSH COUNTRY LATE MORNING AND EARLY AFTERNOON. FOLLOWING
CLOSE TO THE HIGH RES 18Z HRRR FOR THE REST OF THIS AFTERNOON AND
EVENING...WHICH WAS THE ONLY MODEL THAT SEEMED TO HAVE A DECENT
HANDLE ON THE SITUATION. THE LINE WILL CONTINUE EAST INTO THE
INLAND COASTAL BEND OVER THE NEXT 2 HOURS...THEN POSSIBLY WEAKEN
AS OUTFLOW BOUNDARY PUSHES OUT AHEAD OF IT (MAY BE EVIDENCE OF
THIS OUTFLOW BOUNDARY ALREADY DEVELOPING. THE ENVIRONMENT ACROSS
THE EASTERN BRUSH COUNTRY AND COASTAL BEND IS UNSTABLE...WITH
MLCAPE 2000-2500 J/KG AND UNCAPPED. SHEAR IS RELATIVELY
WEAK...NEVERTHELESS A FEW STRONGER STORMS PRODUCING SMALL HAIL AND
WIND GUSTS UP TO 50 MPH ARE POSSIBLE OVER THE NEXT COUPLE OF
HOURS. CONVECTION SHOULD GRADUALLY END AROUND OR AFTER SUNSET.
&&
.LONG-TERM (SATURDAY THROUGH FRIDAY)...WEAK SHORTWAVES WILL CONTINUE
TO AFFECT SOUTH TEXAS ON SATURDAY AND INTO SUNDAY. MODELS ALL
INDICATE ENERGY WITH THESE SHORTWAVES...BUT ARE A BIT DIFFERENT IN
THE FINER DETAILS. STILL THINK THE NEXT WAVE TOMORROW COULD BRING A
SLIGHT CHANCE FOR THUNDERSTORMS TO THE AREA. HAVE SPREAD THE SLIGHT
CHANCE AREA FARTHER EAST GIVEN INCREASED MOISTURE FARTHER EAST THAN
PREVIOUS MODELS HAD INDICATED. HAVE A LINGERING 10 POP WITH SLIGHT
CHANCE WORDING FOR SUNDAY AS A SHORTWAVE WEAKER THAN THE OTHERS
PASSES BY...BUT GUIDANCE STILL INDICATING SOME QPF ACROSS THE AREA.
FOR MONDAY AND TUESDAY HIGH PRESSURE RIDGE BUILDS STRONGER ACROSS
THE AREA WHILE 850 THETA E RIDGE SHIFTS WESTWARD. THIS WILL DRY
THINGS OUT A BIT IN THE MID LEVELS AND ALLOW TEMPERATURES TO
INCREASE. INCREASED PRESSURE GRADIENT WITH RESULTING FROM THE
STRENGTHENING RIDGE TO THE EAST WILL ALSO INCREASE WINDS ACROSS THE
AREA EARLY IN THE WEEK. SMALL CRAFT ADVISORY CONDITIONS ARE POSSIBLE
BY MID-WEEK.
AN UPPER LEVEL TROUGH WILL BE DIGGING INTO THE WESTERN US BY MID
WEEK AS WELL. MODEL SOLUTIONS HAVE NOT BEEN CONSISTENT WITH THE
AMPLITUDE OF THIS TROUGH. SOME MODELS INDICATE A PRETTY DEEP TROUGH
DIGGING AS FAR SOUTH AS NORTHERN MEXICO. OTHER MODELS SHOW A MUCH
WEAKER TROUGH. NOT CONFIDENT YET IN CHANCES FOR PRECIP
THURSDAY/FRIDAY...BUT WILL LEAVE 20 POPS FROM PREVIOUS FORECAST AT
THIS TIME.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 76 89 75 90 75 / 30 10 10 10 10
VICTORIA 74 88 72 90 71 / 30 20 10 10 10
LAREDO 75 92 74 96 74 / 30 20 10 10 10
ALICE 75 89 73 92 73 / 30 20 10 10 10
ROCKPORT 75 87 75 88 76 / 30 10 10 10 10
COTULLA 74 91 72 95 72 / 30 30 10 10 10
KINGSVILLE 76 90 75 91 74 / 30 10 10 10 10
NAVY CORPUS 75 86 75 87 76 / 30 10 10 10 10
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...NONE.
&&
$$
JR/76...SHORT TERM
PZ/83...LONG TERM
AREA FORECAST DISCUSSION...UPDATED
NWS LUBBOCK TX
104 PM CDT FRI MAY 24 2013
.UPDATE...
18Z AVIATION DISCUSSION INCLUDED BELOW. SMALL UPDATE MOSTLY TO
BUMP UP HIGH TEMPS ACROSS THE BOARD TODAY GIVEN RECENT OBSERVED
TRENDS. POP-WISE...THE BEST CHANCES FOR AFTN TSTRMS ARE TENDING TO
FAVOR OUR EASTERN COUNTIES IN LIGHT OF A SLOWLY-RETREATING AREA OF
CUMULUS OBSERVED FROM QUANAH SOUTH TO HASKELL. RECENT HRRR RUNS
SEEM THE MOST CREDIBLE WITH INITIATION NEAR OUR EASTERN-MOST
COUNTIES BY EARLY-MID AFTN WITH REDUCED CHANCES FARTHER WEST.
RECENT LUBBOCK RADAR AND WTM STATIONS HAVE SHOWN A SUBTLE OUTFLOW
BOUNDARY LIFTING NORTHWEST BETWEEN TAHOKA AND GRAHAM...ALTHOUGH I
AM NOT OPTIMISTIC THIS FEATURE WILL IMPROVE CHANCES FOR PRECIP ON
THE CAPROCK AS WATER VAPOR SHOWS A NARROW ZONE OF SUBSIDENCE
SPREADING NORTH. REMAINDER OF THE FORECAST REMAINS IN CHECK.
&&
.AVIATION...
VFR CONDITIONS THIS AFTERNOON COULD BE THREATENED BY A FEW +TSRA
WITH THE BEST CHANCE OF THIS OCCURRING AT CDS...HOWEVER LOW
COVERAGE OF STORMS IMPLIES KEEPING PRECIP MENTION OUT FOR NOW.
CONFIDENCE IS HIGHER THAT LOW CIGS AND/OR SOME LIGHT FOG WILL
DEVELOP EARLY SAT MORNING AT THE TERMINALS...SO HAVE INSERTED A
PERIOD OF MVFR CONDITIONS AS MOIST SELY WINDS REMAIN INTACT.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 84 60 84 60 93 / 20 20 20 20 20
TULIA 83 62 83 60 92 / 20 20 20 20 10
PLAINVIEW 84 63 83 61 91 / 20 20 20 20 10
LEVELLAND 85 64 84 62 92 / 20 20 20 20 10
LUBBOCK 84 65 83 63 92 / 20 20 20 20 10
DENVER CITY 85 64 84 61 92 / 20 20 20 20 10
BROWNFIELD 85 65 84 62 92 / 20 20 20 20 10
CHILDRESS 83 66 85 66 93 / 30 20 20 20 10
SPUR 83 66 82 63 91 / 20 20 20 20 10
ASPERMONT 84 67 84 66 92 / 30 20 20 20 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
93/99/93
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
648 AM CDT FRI MAY 24 2013
.AVIATION...
THE TAF FORECAST REMAINS NEBULOUS FOR TODAY BEGINNING THIS
MORNING. LOW CIGS AT KCDS WILL LIKELY DISSIPATE BY LATE MORNING
AND THESE CIGS ARE NOT ANTICIPATED TO AFFECT KLBB. THUNDERSTORMS
MAY DEVELOP THIS AFTERNOON AT BOTH TAF SITES BUT UNCERTAINTY IS
VERY HIGH SO A PROB30 MENTION WAS PLACED IN THE TAFS FOR NOW.
&&
.PREV DISCUSSION... /ISSUED 440 AM CDT FRI MAY 24 2013/
SHORT TERM...
OVERALL CHANCES OF CONVECTION WILL BE LESS FAVORABLE TODAY THAN
YESTERDAY. THERE IS AN OVERALL LACK OF FORCING BOTH LARGE AND AT THE
MESOSCALE LEVEL. UPPER LEVEL JET WINDS WILL UNDERGO A SIGNIFICANT
WEAKENING WITH A LACK OF A FOCUSED AREA OF UPPER LEVEL DIVERGENCE.
SOUTHWEST FLOW ALOFT WILL CONTINUE TO PERSIST OVER THE REGION BUT
THERE ARE NO DISCERNIBLE SHORT WAVES WITH THE FLOW FOR THIS
AFTERNOON. ANY WELL DEFINED LOW LEVEL BOUNDARY WILL BE WELL AWAY
FROM THE REGION WITH LITTLE TO NO LOW LEVEL FOCUS RESOLVED BY MODEL
SOLUTIONS. THE ONLY LOW LEVEL BOUNDARY MAY BE A LEFT OVER CONVECTIVE
BOUNDARY FROM CONVECTION EARLY THIS MORNING. OTHERWISE...THE ONLY
LOW LEVEL ENHANCEMENT MAY BE ALONG THE EDGE OF THE CAPROCK WITH
SOUTHEASTERLY WINDS. FURTHERMORE...ISENTROPIC SURFACES WILL BE
COMPOSED OF DOWNGLIDE.
THERE WILL BE NO SHORTAGE OF ATMOSPHERIC INSTABILITY. INSTABILITY
WILL BALLOON TO BETWEEN 2000-3000 J/KG WITH MAXIMUM VALUES OVER THE
ROLLING PLAINS WHERE MOISTURE IS DEEPEST. THE RAP EVEN SHOWS AN
ASTOUNDING 6000 J/KG OF SURFACE BASED CAPE BY THE AFTERNOON. SURFACE
DEW POINTS ARE NOT EXPECTED TO MIX OUT AS MUCH AS THEY DID ON
THURSDAY. SOUTHEAST WINDS WILL KEEP SURFACE DEW POINTS IN JUICY
TERRITORY RANGING FROM UPPER 50S TO MID 60S. PRECIPITABLE WATER
VALUES MAINTAIN RESPECTABLE VALUES BETWEEN 1.00 AND 1.25 INCHES.
HODOGRAPHS DEPICT GOOD TURNING IN LOW LEVELS BUT WIND SPEEDS ARE
FAIRLY LIGHT THROUGH MID LEVELS. THIS IS ALSO REFLECTED IN DEEP
LAYER SHEAR PROGS. SHEAR VECTORS FROM 0-6KM ARE ON THE ORDER OF ONLY
25-30KT. THIS WOULD LEAD TO FAIRLY SLOW STORM MOTIONS ALLOWING FOR A
DELUGE OF RAINFALL. OVERALL...CONVECTION LOOKS TO BE POORLY
ORGANIZED FOR TODAY. MODELS ARE ALSO INITIATING BY LATE IN THE
MORNING WHICH SEEMS EQUIVOCAL GIVEN THAT THE ATMOSPHERE WILL
REMAINED CAPPED UNTIL THE EARLY AFTERNOON AMONG OTHER REASONS
DISCUSSED ABOVE. LASTLY...WITH DEW POINTS NOT ANTICIPATED TO MIX OUT
NEARLY AS MUCH TODAY...TEMPERATURES WILL BE SIGNIFICANTLY COOLER
THIS AFTERNOON WITH MOSTLY 80S FORECAST. JDV
LONG TERM...
SOUTHWEST FLOW ALOFT EXPECTED TO REMAIN OVER THE SOUTH PLAINS
REGION THROUGH THE MIDDLE OF THE COMING WEEK. MOISTURE FLOW WILL
CONTINUE NORTHWARD WITH PRECIPITABLE WATER VALUES HOLDING IN
EXCESS OF AN INCH MORE OR LESS OVER THE CENTER OF THE AREA...LESS
WEST AND MORE EAST OF COURSE. THE SURFACE DRY-LINE WILL LIKELY
SLOSH MOSTLY BETWEEN THE WESTERN AND EASTERN SOUTH PLAINS DURING
THIS PERIOD...WHILE PRECISE LOCATIONS AT PEAK AFTERNOON HEATING
PERIODS REMAINS UNCERTAIN. INSTABILITY LEVELS ALSO EXPECTED TO
HOLD IN THE 1000-2000 JOULES PER KILOGRAM RANGE. WEAK EJECTING
DISTURBANCES MAY PROVIDE ENOUGH LIFT AT TIMES...WHILE WEAKLY
CONVERGENT LOW LEVEL FLOW ALSO COULD GENERATE LOW COVERAGE THUNDER
CHANCES THROUGH TUESDAY.
A STRONGER TROUGH STILL SEEMS LIKELY TO EJECT LATE WEDNESDAY AND
THURSDAY...PERHAPS IN TWO OR MORE PARTS LIKE THE GFS OR AS A
STRONGER TROUGH OR UPPER LOW LIKE THE ECMWF. EITHER WAY SHOULD
SUPPORT MORE BACKED UPPER FLOW AND EVEN DEEPER MOISTURE WEDNESDAY
AND OR THURSDAY AND MAY END UP WITH A MORE WIDESPREAD SEVERE
WEATHER THREAT AS WELL. THIS IS A STRONG ENOUGH AND CONSISTENT
ENOUGH SIGNAL FOR NOW TO RAISE THUNDERSTORM MENTION INTO THE
CHANCE CATEGORY WEDNESDAY. TEMPERATURES SHOULD WARM A BIT ABOVE
NORMAL LATE IN THE WEEKEND AND EARLY NEXT WEEK...WHILE WINDS
SHOULD INCREASE BY MID-WEEK WITH THE PASSING UPPER LOW OR LOW
PRESSURE TROUGH. RMCQUEEN
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 84 60 84 60 93 / 30 30 20 20 20
TULIA 83 62 83 60 92 / 30 30 20 20 10
PLAINVIEW 83 63 83 61 91 / 30 30 20 20 10
LEVELLAND 85 64 84 62 92 / 30 30 20 20 10
LUBBOCK 83 65 83 63 92 / 30 30 20 20 10
DENVER CITY 85 64 84 61 92 / 30 30 20 20 10
BROWNFIELD 85 65 84 62 92 / 30 30 20 20 10
CHILDRESS 83 66 85 66 93 / 30 30 20 20 10
SPUR 82 66 82 63 91 / 30 30 20 20 10
ASPERMONT 85 67 84 66 92 / 40 40 20 20 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
01/99/99
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
440 AM CDT FRI MAY 24 2013
.SHORT TERM...
OVERALL CHANCES OF CONVECTION WILL BE LESS FAVORABLE TODAY THAN
YESTERDAY. THERE IS AN OVERALL LACK OF FORCING BOTH LARGE AND AT THE
MESOSCALE LEVEL. UPPER LEVEL JET WINDS WILL UNDERGO A SIGNIFICANT
WEAKENING WITH A LACK OF A FOCUSED AREA OF UPPER LEVEL DIVERGENCE.
SOUTHWEST FLOW ALOFT WILL CONTINUE TO PERSIST OVER THE REGION BUT
THERE ARE NO DISCERNIBLE SHORT WAVES WITH THE FLOW FOR THIS
AFTERNOON. ANY WELL DEFINED LOW LEVEL BOUNDARY WILL BE WELL AWAY
FROM THE REGION WITH LITTLE TO NO LOW LEVEL FOCUS RESOLVED BY MODEL
SOLUTIONS. THE ONLY LOW LEVEL BOUNDARY MAY BE A LEFT OVER CONVECTIVE
BOUNDARY FROM CONVECTION EARLY THIS MORNING. OTHERWISE...THE ONLY
LOW LEVEL ENHANCEMENT MAY BE ALONG THE EDGE OF THE CAPROCK WITH
SOUTHEASTERLY WINDS. FURTHERMORE...ISENTROPIC SURFACES WILL BE
COMPOSED OF DOWNGLIDE.
THERE WILL BE NO SHORTAGE OF ATMOSPHERIC INSTABILITY. INSTABILITY
WILL BALLOON TO BETWEEN 2000-3000 J/KG WITH MAXIMUM VALUES OVER THE
ROLLING PLAINS WHERE MOISTURE IS DEEPEST. THE RAP EVEN SHOWS AN
ASTOUNDING 6000 J/KG OF SURFACE BASED CAPE BY THE AFTERNOON. SURFACE
DEW POINTS ARE NOT EXPECTED TO MIX OUT AS MUCH AS THEY DID ON
THURSDAY. SOUTHEAST WINDS WILL KEEP SURFACE DEW POINTS IN JUICY
TERRITORY RANGING FROM UPPER 50S TO MID 60S. PRECIPITABLE WATER
VALUES MAINTAIN RESPECTABLE VALUES BETWEEN 1.00 AND 1.25 INCHES.
HODOGRAPHS DEPICT GOOD TURNING IN LOW LEVELS BUT WIND SPEEDS ARE
FAIRLY LIGHT THROUGH MID LEVELS. THIS IS ALSO REFLECTED IN DEEP
LAYER SHEAR PROGS. SHEAR VECTORS FROM 0-6KM ARE ON THE ORDER OF ONLY
25-30KT. THIS WOULD LEAD TO FAIRLY SLOW STORM MOTIONS ALLOWING FOR A
DELUGE OF RAINFALL. OVERALL...CONVECTION LOOKS TO BE POORLY
ORGANIZED FOR TODAY. MODELS ARE ALSO INITIATING BY LATE IN THE
MORNING WHICH SEEMS EQUIVOCAL GIVEN THAT THE ATMOSPHERE WILL
REMAINED CAPPED UNTIL THE EARLY AFTERNOON AMONG OTHER REASONS
DISCUSSED ABOVE. LASTLY...WITH DEW POINTS NOT ANTICIPATED TO MIX OUT
NEARLY AS MUCH TODAY...TEMPERATURES WILL BE SIGNIFICANTLY COOLER
THIS AFTERNOON WITH MOSTLY 80S FORECAST. JDV
&&
.LONG TERM...
SOUTHWEST FLOW ALOFT EXPECTED TO REMAIN OVER THE SOUTH PLAINS
REGION THROUGH THE MIDDLE OF THE COMING WEEK. MOISTURE FLOW WILL
CONTINUE NORTHWARD WITH PRECIPITABLE WATER VALUES HOLDING IN
EXCESS OF AN INCH MORE OR LESS OVER THE CENTER OF THE AREA...LESS
WEST AND MORE EAST OF COURSE. THE SURFACE DRY-LINE WILL LIKELY
SLOSH MOSTLY BETWEEN THE WESTERN AND EASTERN SOUTH PLAINS DURING
THIS PERIOD...WHILE PRECISE LOCATIONS AT PEAK AFTERNOON HEATING
PERIODS REMAINS UNCERTAIN. INSTABILITY LEVELS ALSO EXPECTED TO
HOLD IN THE 1000-2000 JOULES PER KILOGRAM RANGE. WEAK EJECTING
DISTURBANCES MAY PROVIDE ENOUGH LIFT AT TIMES...WHILE WEAKLY
CONVERGENT LOW LEVEL FLOW ALSO COULD GENERATE LOW COVERAGE THUNDER
CHANCES THROUGH TUESDAY.
A STRONGER TROUGH STILL SEEMS LIKELY TO EJECT LATE WEDNESDAY AND
THURSDAY...PERHAPS IN TWO OR MORE PARTS LIKE THE GFS OR AS A
STRONGER TROUGH OR UPPER LOW LIKE THE ECMWF. EITHER WAY SHOULD
SUPPORT MORE BACKED UPPER FLOW AND EVEN DEEPER MOISTURE WEDNESDAY
AND OR THURSDAY AND MAY END UP WITH A MORE WIDESPREAD SEVERE
WEATHER THREAT AS WELL. THIS IS A STRONG ENOUGH AND CONSISTENT
ENOUGH SIGNAL FOR NOW TO RAISE THUNDERSTORM MENTION INTO THE
CHANCE CATEGORY WEDNESDAY. TEMPERATURES SHOULD WARM A BIT ABOVE
NORMAL LATE IN THE WEEKEND AND EARLY NEXT WEEK...WHILE WINDS
SHOULD INCREASE BY MID-WEEK WITH THE PASSING UPPER LOW OR LOW
PRESSURE TROUGH. RMCQUEEN
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 84 60 84 60 93 / 30 30 20 20 20
TULIA 83 62 83 60 92 / 30 30 20 20 10
PLAINVIEW 83 63 83 61 91 / 30 30 20 20 10
LEVELLAND 85 64 84 62 92 / 30 30 20 20 10
LUBBOCK 83 65 83 63 92 / 30 30 20 20 10
DENVER CITY 85 64 84 61 92 / 30 30 20 20 10
BROWNFIELD 85 65 84 62 92 / 30 30 20 20 10
CHILDRESS 83 66 85 66 93 / 30 30 20 20 10
SPUR 82 66 82 63 91 / 30 30 20 20 10
ASPERMONT 85 67 84 66 92 / 40 40 20 20 10
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
01/05
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
641 PM CDT SAT MAY 25 2013
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 341 PM CDT SAT MAY 25 2013
AT 3 PM...A DYING MESOSCALE CONVECTIVE COMPLEX WAS LOCATED OVER
CENTRAL ILLINOIS. THIS SYSTEM PRODUCED UP TO 4 INCHES OF RAIN
ACROSS PARTS OF STORY...MARSHALL...AND JASPER COUNTIES IN CENTRAL
IOWA. MEANWHILE NORTHEAST IOWA AND MOWER COUNTY IN SOUTHEAST
MINNESOTA...RECEIVED UP TO A THIRD OF AN INCH /KARX RADAR WAS
OVERESTIMATING BY UP TO 300 PERCENT IN SOME LOCATIONS/. THE RAIN
AND CLOUDS FROM THIS SYSTEM KEPT TEMPERATURES IN THE LOWER AND MID
50S IN THESE AREAS WHICH IS VERY CLOSE TO THE RECORD COLDEST
MAXIMUM TEMPERATURES FOR THE DATE. THE RECORD COLD MAXIMUM FOR THE
DATE IS 46 IN 1992 FOR AUSTIN MN...48 IN 1943 IN CHARLES CITY
IA...AND 53 IN 1992 IN DECORAH IA. THE DECORAH RECORD IS THE ONLY
ONE THAT COULD POSSIBLY BE BROKEN OR TIED. MEANWHILE AREAS NORTH
OF INTERSTATE 94 SAW A BIT OF SUNSHINE AND THEY WERE ABLE TO WARM
INTO THE MID 60S.
FOR TONIGHT AND SUNDAY...THE MAIN CONCERN IS THE TRACK OF THE
MESOSCALE CONVECTIVE COMPLEX OVER WESTERN NORTH DAKOTA. CORFIDI
VECTORS SUGGEST THAT THIS SYSTEM WILL MOVE EAST ACROSS THE DAKOTAS
THIS EVENING...AND THEN IT WILL MOVE SOUTHEAST ACROSS THE EASTERN
THIRD OF SOUTH DAKOTA...SOUTHERN AND WESTERN MINNESOTA AND NORTHERN
IOWA TONIGHT. OVERALL...THE 25.18Z HRRR HAS THE BEST HANDLE ON THIS
SYSTEM AND IT HAS THIS SYSTEM OVER SOUTHWEST MINNESOTA BY 26.06Z.
WITH THAT SPEED...IT SHOULD MOVE INTO NORTHEAST IOWA AND PARTS OF
SOUTHEAST MINNESOTA BY 26.10Z...AND THEN LINGER ACROSS THESE AREAS
THROUGH MUCH OF SUNDAY MORNING. AHEAD OF THIS SYSTEM...THE
RAP...GFS...NAM/WRF...AND ECMWF SHOW THAT SCATTERED SHOWERS AND
THUNDERSTORMS WILL DEVELOP NORTH OF A WARM FRONT FROM NORTHWEST
IOWA TO SOUTHEAST IOWA. THIS PRECIPITATION IS ASSOCIATED WITH
MODERATE 925 TO 850 MB MOISTURE TRANSPORT AND 310K ISENTROPIC
LIFT.
LIKE TODAY...EXPECT THE LOW CLOUDS AND PRECIPITATION TO KEEP
TEMPERATURES IN THE MID AND UPPER 50S ACROSS SOUTHEAST
MINNESOTA...NORTHEAST IOWA...AND SOUTHWEST WISCONSIN ON SUNDAY.
MEANWHILE SOME SUN NORTH OF INTERSTATE 94 WILL ALLOW TEMPERATURES
TO WARM INTO THE MID 60S.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 341 PM CDT SAT MAY 25 2013
ON SUNDAY NIGHT AND MONDAY...THE WARM FRONT WILL MOVE INTO NORTH
SOUTHWEST IOWA. WEAK TO MODERATE 925 AND 850 MB MOISTURE TRANSPORT
WILL RESULT IN THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS NORTH
OF THE WARM FRONT FROM NORTH CENTRAL IOWA SOUTHEAST INTO SOUTHEAST
IOWA. THE GFS...ECMWF...AND GEM SUGGEST THAT A MESOSCALE
CONVECTIVE COMPLEX WILL DEVELOP ACROSS EASTERN SOUTH DAKOTA LATE
SUNDAY NIGHT...AND THE DYING SYSTEM MOVES EAST THROUGH OUR AREA
MONDAY.
FROM MONDAY NIGHT INTO TUESDAY...THE MODELS ARE CONTINUING TO
STRUGGLE WITH THE LOCATION OF THE WARM FRONT. THE NAM/WRF STALLS
THE WARM FRONT NEAR THE MINNESOTA AND IOWA BORDER. THIS MAKES A
LOT OF SENSE IF A LOT OF CONVECTION DEVELOPS NORTH OF THIS FRONT
AND ITS COLD POOL PREVENTS THIS WARM FRONT MOVING ANY FURTHER
NORTH. MEANWHILE THE GFS AND ECMWF WOULD SYNOPTICALLY FAVOR THAT
THE WARM FRONT WOULD MOVE NORTHWARD THROUGH THE AREA. HOWEVER THE
CAP IN THE WARM SECTOR REMAINS SOUTHWEST OF THE FORECAST
AREA...THUS THERE WOULD BE THE POTENTIAL FOR A SERIES OF MESOSCALE
CONVECTIVE SYSTEMS TO MOVE THROUGH THE AREA. SO IN EITHER
SCENARIO...IT LOOKS LIKE THE FORECAST AREA WILL REMAIN WET. WITH
PRECIPITABLE WATER VALUES AROUND 1.5 INCHES AND WARM CLOUD LAYER
DEPTHS UP TO 4KM...THERE WILL BE THE POTENTIAL FOR HEAVY RAIN FROM
ANY SHOWERS AND THUNDERSTORMS THAT DEVELOP. IN ADDITION...WILL
HAVE TO WATCH FOR THE POTENTIAL OF SEVERE WEATHER...BUT THIS IS
HIGHLY DEPENDENT UPON THE LOCATION OF THE WARM FRONT.
FROM TUESDAY NIGHT INTO SATURDAY...IT CONTINUES TO LOOK LIKE A
SERIES OF SHORT WAVE TROUGHS WILL MOVE THROUGH THE REGION. HOWEVER
THE TIMING OF THESE WAVES IS UNCERTAIN...THUS KEPT PRECIPITATION
CHANCES IN THE 40 TO 60 PERCENT RANGE THROUGH THIS TIME PERIOD.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SUNDAY EVENING)
ISSUED AT 641 PM CDT SAT MAY 25 2013
PREVAILING SOUTHEASTERLY FLOW WILL KEEP FEED OF OF DRIER AIR IN
PLACE THROUGH THE EVENING AND OVERNIGHT...ALLOWING CEILINGS TO
REMAIN VFR KRST/KLSE. AS SHOWERS AND THUNDERSTORMS ERUPT ACROSS THE
DAKOTAS...THIS SHOULD FORM INTO AN ORGANIZED SYSTEM AND MOVE
TOWARD THE REGION. THERE REMAINS SOME UNCERTAINTY WHERE THIS WILL
EXACTLY TRACK...BUT THE FAVORED AREAS ARE WEST CENTRAL MINNESOTA
TO CENTRAL IOWA. THIS COULD POSSIBLY CLIP KRST WITH SOME SHOWERS
IN THE EARLY MORNING HOURS...LASTING UNTIL LATE MORNING. CEILINGS
WILL LIKELY START OFF AS VFR ONCE SHOWERS COMMENCE...BUT THEN DROP
TO MVFR AFTER A FEW HOURS. AT KLSE...CONFIDENCE IN A DRY FORECAST
IS HIGHER SO HAVE KEPT VFR CONDITIONS THROUGH MOST OF THE PERIOD.
FINALLY...CONFIDENCE FOR SUNDAY AFTERNOON LOWERS AT BOTH TAF
SITES...AS THERE COULD BE SHOWERS AROUND...BUT AGAIN THE HIGHER
CHANCES FOR A LONGER PERIOD OF PRECIPITATION IS SOUTH AND WEST OF
THE TAF SITES SO HAVE KEPT FORECAST DRY AT THIS POINT.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...ZT
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
336 PM CDT FRI MAY 24 2013
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 334 PM CDT FRI MAY 24 2013
AT 3 PM...A 1003 MB HIGH PRESSURE SYSTEM...CENTERED OVER LAKE
MICHIGAN...KEPT SKIES PARTLY SUNNY ACROSS THE UPPER MISSISSIPPI
RIVER VALLEY. MEANWHILE FURTHER WEST...A SHORT WAVE WAS PRODUCING
SHOWERS AND THUNDERSTORMS ACROSS THE EASTERN QUARTER OF THE
DAKOTAS AND WESTERN MINNESOTA. THE MESO AND DETERMINISTIC MODELS ARE
CONTINUING TO STRUGGLE WITH THE EASTWARD PROGRESS OF THIS
PRECIPITATION TONIGHT. THE ECMWF AND HRRR MOVE THIS PRECIPITATION
ACROSS MOST OF FORECAST AREA BY 25.06Z. MEANWHILE THE
NMM...ARW...GFS...GEM...RAP... AND NAM MAINLY CONFINE THE
PRECIPITATION WEST OF THE MISSISSIPPI RIVER THIS EVENING...AND
THEN MOVES IT ACROSS THE REMAINDER OF THE AREA OVERNIGHT. SINCE
THE CONVECTION ACROSS THE DAKOTAS WILL BE MOVING INTO AN AREA WITH
LESS FRONTOGENETIC FORCING...MOISTURE TRANSPORT...WEAK ISENTROPIC
LIFT...AND DRIER AIR...DECIDED TO TREND THE FORECAST TOWARD THE
LATTER MODEL SET. IN ADDITION...THE RADAR ECHOS ACROSS WESTERN
MINNESOTA ARE SHOWING A DECREASING TREND. EVEN BY DOING
THIS...THERE IS SOME VARIATIONS AMONGST THEM...SO TRIED TO GO WITH
AN ENSEMBLE APPROACH WHEN ASSIGNING THE HOURLY PRECIPITATION
CHANCES. THE HIGHEST PRECIPITATION CHANCE AND AMOUNTS /UP TO A
HALF INCH/ WILL BE FOUND ACROSS ACROSS SOUTHEAST MINNESOTA AND
NORTHEAST IOWA.
ON SATURDAY...THE SHORT WAVE WILL MOVE EAST SOUTHEAST ACROSS IOWA.
AS THIS OCCURS...THE 850 MB MOISTURE TRANSPORT AND ISENTROPIC LIFT
WILL GRADUALLY WEAKEN. AS A RESULT...WENT WITH A DECREASING TREND
IN THE PRECIPITATION TRENDS FROM LATE MORNING INTO THE AFTERNOON.
ADDITIONAL RAIFALL AMOUNTS WILL BE LESS THAN 2 TENTHS OF AN INCH.
WITH THE 24.12Z AND 24.18Z MODELS IN GOOD AGREEMENT THAT THERE
WILL BE LESS THAN 100 J/KG CAPES...JUST KEPT AN ISOLATED
THUNDERSTORM CHANCE MAINLY WEST AND SOUTH IF THE INTERSTATE 94
CORRIDOR.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 334 PM CDT FRI MAY 24 2013
FROM SATURDAY NIGHT THROUGH SUNDAY NIGHT...THE WARM FRONT WILL
REMAIN WELL SOUTHWEST OF THE FORECAST AREA. AS A RESULT...
SOUTHEAST MINNESOTA...NORTHEAST IOWA...AND SOUTHWEST WISCONSIN
WILL REMAIN CLOUDY WITH PERIODIC SHOWERS AND MAYBE AN ISOLATED
THUNDERSTORM. OVER THE PAST 3 DAYS...THE CONSALL HAS CONTINUED
TO TREND TOWARD COOLER HIGH TEMPERATURES FOR SUNDAY. IT NOW HAS
HIGH TEMPERATURES AROUND 60. MEANWHILE THE ECMWF ONLY HAS HIGH
TEMPERATURES IN THE LOWER 50S FOR THESE AREAS. SINCE THE ECMWF
TYPICALLY VERIFIES THE BEST FOR THIS TIME PERIOD...WENT WITH A
BLEND OF THE CONSALL...CONSALLBC...AND EMCWF.
FROM MEMORIAL DAY INTO TUESDAY...THE MODELS ARE CONTINUING TO SHOW
THAT A WARM FRONT WILL MOVE NORTHWARD INTO THE AREA. THIS WILL
ALLOW ML CAPES TO CLIMB INTO THE 1K TO 3K J/KG RANGE. AS A
RESULT...EXPECT THE THUNDERSTORM CHANCES TO INCREASE DURING THIS
TIME PERIOD. THE 0-3KM SHEAR WOULD BE FAVORABLE FOR THE
POSSIBILITY THAT A FEW THUNDERSTORMS MAY BE CAPABLE OF PRODUCING
LARGE HAIL AND DAMAGING WINDS.
FROM TUESDAY NIGHT INTO FRIDAY...THE MODELS CONTINUE TO STRUGGLE
ON WHERE THE WARM SECTOR WILL BE LOCATED. THIS GREATLY AFFECTS
THE WHERE THE PRECIPITATION MAY BE LOCATED. IN ADDITION...IT WILL
ALSO AFFECT THE SHEAR AND INSTABILITY...THUS...THERE IS A LOT OF
UNCERTAINTY ON WHETHER THERE WILL BE ANY SEVERE WEATHER.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON)
ISSUED AT 1214 PM CDT FRI MAY 24 2013
FOCUS OF THE FORECAST IS ON THE POTENTIAL FOR SHOWERS LATE TONIGHT
INTO SATURDAY MORNING. SHORT WAVE TROUGH IN THE LEE OF THE ROCKIES
OVER WYOMING IS EXPECTED TO TOP THE MEAN RIDGE AND SLIDE ACROSS
THE REGION LATE TONIGHT AND SATURDAY MORNING. AN AXIS OF MOISTURE
TRANSPORT IS EXPECTED TO DEVELOP THIS AFTERNOON AHEAD OF THIS WAVE
THEN BEND TO THE NORTHEAST AND BE FOCUSED INTO THE AREA LATE
TONIGHT. HOWEVER...THIS WILL BE WEAKENING THROUGH THE NIGHT AND
WILL NOT BE VERY STRONG BY THE TIME IT BECOMES FOCUSED ON THE
LOCAL AREA. THE FORCING FROM THE WAVE AND THE WEAK MOISTURE
TRANSPORT SHOULD BE ENOUGH TO GENERATE SOME SHOWERS. EXPECT THESE
WILL MOVE INTO BOTH TAF SITES BETWEEN 09Z AND 12Z. THE SHOWERS
SHOULD BE LIGHT ENOUGH TO NOT PRODUCE ANY VISIBILITY RESTRICTION
BUT COULD PRODUCE SOME MVFR CEILINGS AS THE RAIN SATURATES THE LOW
LEVELS OF THE COLUMN ENOUGH TO ALLOW THE CEILINGS TO LOWER. THE
24.09Z SREF SHOWS THE BETTER PROBABILITIES OF THIS OCCURRING ARE
WEST OF THE MISSISSIPPI RIVER SO HAVE INCLUDED THIS AT KRST. THE
ISENTROPIC UPGLIDE ON THE 300K SURFACE BEGINS TO WEAKEN AFTER 15Z
SATURDAY BUT DOES CONTINUE FOR THE REMAINDER OF THE MORNING AND
SHOULD BE ENOUGH TO KEEP SOME SHOWERS OR SPRINKLES GOING THROUGH
THE END OF THE FORECAST PERIOD.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...04
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE
.SHORT TERM...TONIGHT AND SATURDAY
ISSUED AT 248 PM CDT FRI MAY 24 2013
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW HIGH
PRESSURE STRETCHING FROM HUDSON BAY TO LAKE MICHIGAN TO THE
CENTRAL GULF COAST. A FEW STRANDS OF CIRRUS IS INVADING NW
WISCONSIN EARLY THIS AFTERNOON...BUT OTHERWISE...CLEAR AND COOL
CONDITIONS ARE PREVAILING. LOOKING UPSTREAM...STRENGTHENING RETURN
FLOW OVER THE PLAINS IS CREATING A BAND OF SHOWERS AND
THUNDERSTORMS OVER EASTERN NORTH AND SOUTH DAKOTA. AS THIS WARM
FRONT SHIFTS EAST TONIGHT...PRECIP CHANCES ARE THE MAIN FORECAST
CONCERN.
TONIGHT...A JET STREAK...BETWEEN A SE DIVING SHORTWAVE OVER THE
EASTERN GREAT LAKES AND A MID-LEVEL RIDGE OVER THE GREAT
PLAINS...WILL SLIDE SOUTHEAST ACROSS THE REGION. RIGHT REAR QUAD OF
THIS JET STREAK WILL SHIFT OVER NORTH-CENTRAL AND NORTHEAST
WISCONSIN AFTER MIDNIGHT. DESPITE VERY DRY AIR IN THE LOW
LEVELS...MODELS SPIT OUT A COUPLE BANDS OF PRECIP AS A RESULT OF
MID-LEVEL CONVERGENCE/FGEN AND UPPER DIVERGENCE...THOUGH DIFFER IN
THEIR PLACEMENT. THE LARGEST BAND WILL BE TIED TO THE PRIMARY
BAROCLINIC ZONE OFF TO OUR WEST AND SOUTHWEST...WHICH THE NAM/GFS
HAVE TRENDED A BIT TO THE WEST. HOWEVER...THE 12Z MESOMODELS
CONTINUE TO PUSH THIS BAND OF PRECIP OVER CENTRAL WISCONSIN BETWEEN
06Z AND 12Z. DO NOT HAVE A GOOD FEEL WHERE THIS BAND WILL END UP.
BUT LIGHT LOW LEVEL SE WINDS WILL SUPPLY A STEADY DIET OF DRY
AIR...SO PRECIP WILL HAVE TO FALL OUT OF A MID-DECK...AND GIVEN THE
WEAK FORCING...CANNOT SEE MUCH MORE THAN SPRINKLES LIKE THE PREVIOUS
FORECASTER MENTIONED. GIVEN THE LOW IMPACT AND TO MATCH UP WITH
OFFICES TO THE WEST AND NORTH...WILL KEEP THE MENTION OF SPRINKLES
OVER CENTRAL WISCONSIN. A LOWERING CLOUD DECK WILL KEEP TEMPS WARMER THAN
LAST NIGHT AND WILL GO WITH MID 30S NORTH TO MID 40S SOUTH. PATCHY
FROST WILL REMAIN POSSIBLE OVER FAR NORTHERN WISCONSIN.
SATURDAY...RIGHT REAR QUAD WILL SLIDE TO THE SOUTH-CENTRAL GREAT
LAKES DURING THE MORNING. ANY SPRINKLE ACTIVITY SHOULD BE ENDING
EARLY SO IT DOES NOT SEEM WORTH MENTIONING IN THE FORECAST. THE
DEPARTING MID-LEVEL CONVERGENCE SHOULD ALLOW DRY AIR TO RETURN TO
NORTHEAST WISCONSIN LATE MORNING ONWARD WHEN SHOULD SEE DECREASING
CLOUDS. CLOUDS TO HANG LONGER OVER CENTRAL AND NORTH-CENTRAL
WISCONSIN...CLOSER TO THE PRIMARY BAROCLINIC ZONE. WITH THE
ADDITIONAL CLOUD COVER...TEMPS TO REMAIN NEAR OR SLIGHTLY COOLER
THAN TODAYS READINGS...AND WILL RANGE FROM THE UPPER 50S OVER
CENTRAL WISCONSIN TO THE MIDDLE 60S OVER NORTHEAST WISCONSIN.
.LONG TERM...SATURDAY NIGHT THROUGH FRIDAY
ISSUED AT 248 PM CDT FRI MAY 24 2013
GOOD AGREEMENT BETWEEN GUIDANCE IN BIG PICTURE WITH STRENGTHENING
RIDGE IN THE EAST WHILE TROF PERSISTS OVER THE WEST. PLEASANT
WEATHER IS EXPECTED THROUGH MUCH OF THIS MEMORIAL DAY WEEKEND.
AT THE SURFACE DRY HIGH PRESSURE TO THE EAST WILL MAINTAIN EAST TO
SOUTHEAST FLOW OVER THE REGION. SOME MODEL DISCONNECT WITH HOW
HANDLE SHORT WAVE ACTIVITY EXITING WESTERN TROF INTO THE PLAINS
AND WESTERN LAKES LATE THIS HOLIDAY PERIOD. HAVE STAYED TOWARD
DRIER EC/GFS...WITH IDEA THAT HIGH WILL KEEP PCPN TO OUR SOUTHWEST
SUN AND MON. NAM APPEARS THE OUTLIER...TOO STRONG AND FAST. LIGHT
WINDS AND DRY CONDITIONS TO LEAD TO ANOTHER COOL NIGHT FOR
NORTHEAST WI...WITH PATCHY FROST OVER PARTS OF FAR NORTHEAST WI.
TROF DEEPENS WEST BEGINNING OF NEXT WEEK PUMPING UP RIDGE JUST TO
OUR EAST. THIS TO LEAD TO WARMER TEMPS AND INCREASING HUMIDITY AND
INSTABILITY AS WARM FRONT LIFTS NORTH TOWARDS...OR THROUGH STATE.
AGAIN SOME DISPARITY ON HOW FAR NORTH FRONT WILL GO...WITH EC
LINGERING IT OVER NORTHERN WI. COULD BE LOOKING A PERIOD OF ACTIVE
WEATHER NEXT WED/THU WITH POSSIBILITY OF PERIODS OF HEAVY RAINFALL
AS PW`S INCREASE TO 1.5.
&&
.AVIATION...FOR 18Z TAF ISSUANCE
ISSUED AT 101 PM CDT FRI MAY 24 2013
VFR CONDITIONS EXPECTED FOR THE NEXT FEW DAYS. EVEN ANY SPRINKLES
THAT DEVELOP LATE TNGT/EARLY SAT SHOULD BE FALLING OUT OF A MIDDLE
CLD DECK WITH HIGH BASES. &&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM.....MPC
LONG TERM......TE
AVIATION.......MPC
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1125 PM MDT SAT MAY 25 2013
.UPDATE...
ISSUED AT 806 PM MDT SAT MAY 25 2013
ADJUSTED GRIDS/ZONES TO REFLECT ENDING OF RED FLAG WARNING THIS
EVENING WHILE ALSO CONTINUING THE RED FLAG WARNING FROM 11 AM MDT
SUNDAY TO 9 PM MDT SUNDAY FOR FIRE WEATHER ZONES
221-222-225-227-233 AND 237. ALSO ADJUSTED GRIDS AS NEEDED.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 301 PM MDT SAT MAY 25 2013
...FIRE WEATHER CONCERNS CONTINUE ACROSS THE MTS...AND INCREASE
ACROSS THE SOUTHERN PLAINS ON SUNDAY..
DEEPENING SFC LOW IN VCNTY OF KLHX HAS SPREAD SOME GUSTY SOUTHWEST
WINDS ACROSS THE MOUNTAINS AND SOUTHERN PORTIONS OF THE SE PLAINS.
AS OF 20Z...SFC DRY LINE IS LOCATED ALONG A LINE FROM JUST EAST OF
KLAA...TO NEAR KSPD. TO THE WEST OF THIS LINE...DEW POINTS HAVE BEEN
DROPPING INTO THE SINGLE DIGITS...TEENS AND EVEN SOME NEGATIVE
READINGS ACROSS THE MOUNTAINS. TO THE EAST OF THE DRY LINE...DEW
POINTS ARE STILL IN THE UPPER 40S TO LOWER 50S. LATEST HRRR STILL
PUSHES THE DRY LINE INTO WESTERN KS BY 22Z...WITH DEW POINTS
DROPPING INTO THE 30S ALONG THE EASTERN BORDER. STILL CONCERNED
THAT SOME INITIAL CONVECTION MAY FIRE ALONG THE DRY LINE LATE THIS
AFTERNOON...SO WILL MAINTAIN SOME ISOLATED POPS OUT THAT WAY. MOST
OF IT WILL BE HIGH BASED...WITH GUSTY WINDS AND LIGHTNING THE MOST
LIKELY THREATS. COULDN`T RULE OUT SOME MARGINAL SEVERE HAIL AND
WIND GUSTS NEAR THE CO/KS BORDER IF CAPES CAN STAY UP HIGH ENOUGH.
SPC HAS UPDATED THE LATEST OUTLOOK TO INCLUDE EASTERN
KIOWA...PROWERS...AND BACA COUNTIES. INITIALLY 0-6 KM SHEAR VALUES
ARE AROUND 20-30 KTS WHICH IS MARGINAL FOR SEVERE...BUT THESE VALUES
DO INCREASE INTO THE EVENING...SO THIS AREA WILL NEED TO BE
MONITORED. EXPECT CONVECTION TO SHIFT QUICKLY EASTWARD INTO KS
THROUGH THE LATE AFTN/EARLY EVENING...THOUGH OUTFLOWS MAY AID
WESTWARD RETREAT OF THE DRY LINE.
OVERNIGHT...DRY LINE PROGRESSES BACK WESTWARD BEFORE MIXING BACK
EASTWARD DURING THE DAY ON SUNDAY AS AN UPPER JET IN SOUTHWEST FLOW
ALOFT MOVES ACROSS THE AREA. CURRENT FIRE WEATHER WATCH WILL BE
UPGRADED TO A RED FLAG WARNING WITH THE AFTERNOON PACKAGE AS ALL
AREAS LOOK TO MEET CRITICAL FIRE WEATHER CONDITIONS. SFC BOUNDARY
HANGS UP JUST NORTH OF THE AREA AND WITH DRY LINE EXPECTED TO PUSH
INTO WESTERN KS DURING THE AFTERNOON...WILL GO WITH NIL POPS FOR THE
ENTIRE CWA. LOOKS LIKE HIGHS TOMORROW SHOULD STAY AROUND 3-5 DEGREES
BELOW RECORDS (COS 90...2012 PUB 97...2012 ALS 84...1969)...THOUGH
STILL WAY ABOVE CLIMATOLOGICAL AVERAGES. -KT
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 301 PM MDT SAT MAY 25 2013
SUNDAY NIGHT-MONDAY NIGHT...MODERATE WARM AND DRY SOUTHWEST FLOW
ALOFT CONTINUES ACROSS THE REGION AS A BROAD UPPER TROUGH SLOWLY
DIGS ACROSS THE PAC NORTHWEST AND INTO THE GREAT BASIN. MODELS
CONTINUE TO INDICATE A WEAK EMBEDDED SHORT WAVE TRANSLATING ACROSS
THE ROCKIES SUNDAY NIGHT WITH ANOTHER MINOR WAVE MOVING ACROSS THE
STATE LATE MONDAY AFTERNOON. FIRST WAVE SENDS A WEAK BACKDOOR COLD
FRONT ACROSS EASTERN COLORADO EARLY MONDAY MORNING BEFORE FRONT
MIXES OUT THROUGH THE EARLY AFTERNOON. MODELS ALSO INDICATING
INCREASING MID AND HIGH LEVEL MOISTURE ASSOCIATED WITH SECOND WAVE
SPREADING ACROSS THE AREA THROUGH THE DAY ON MONDAY...WHICH LOOKS TO
LIMIT STRONGER WINDS ALOFT FROM MIXING DOWN THROUGH THE AFTERNOON.
AT ANY RATE...COULD SEE BRIEF RED FLAG CONDITIONS DEVELOPING ACROSS
THE EASTERN MTS LATE MONDAY AFTERNOON...BUT LOOKS TO BE TOO MARGINAL
TO ISSUE ANY HIGHLIGHTS AT THIS TIME. WITH THE PASSING WAVES...COULD
SEE SOME HIGH BASED CONVECTION MONDAY AFTERNOON AND EARLY EVENING
ACROSS MAINLY THE CENTRAL AND EASTERN MTS WITH HIGHS EXPECTED TO BE
ONLY SLIGHTLY COOLER THAN SUNDAY.
TUESDAY-THURSDAY NIGHT...FIRE DANGER EXPECTED TO INCREASE ACROSS
SOUTHERN COLORADO AS GREAT BASIN UPPER TROUGH SLOWLY LIFTS OUT
ACROSS THE NORTHERN ROCKIES THROUGH THE PERIOD. INCREASING SOUTH TO
SOUTHWEST FLOW ACROSS THE AREA TUESDAY DEVELOPS A LA JUNTA LOW
TUESDAY AFTERNOON SUPPORTING THE POTENTIAL FOR CRITICAL FIRE WEATHER
CONDITIONS ACROSS THE SOUTHERN MTS AND ADJACENT PLAINS AS WELL AS
ACROSS THE FAR SOUTHEAST PLAINS...WITH SOME MORE HIGH BASED STORMS
POSSIBLE ACROSS THE CENTRAL MTS AND SOUTHWEST MTS. MORE WIDESPREAD
CRITICAL FIRE WEATHER CONDITIONS LOOK TO BE POSSIBLE ACROSS SOUTHERN
COLORADO WEDNESDAY AND THURSDAY WITH BREEZY TO WINDY WEST TO
SOUTHWEST FLOW ALOFT. PASSING TROUGH KEEPS CHANCE AND SLIGHT CHANCES
OF THUNDERSTORMS ACROSS THE AREA TUESDAY NIGHT THROUGH WEDNESDAY
NIGHT...WITH BEST CHANCES ACROSS NORTHERN PORTIONS OF THE AREA.
MODELS KEEP BEST LOW LEVEL MOISTURE WELL INTO WESTERN KANSAS
THOUGH LATEST ECMWF IS A TAD FURTHER WEST WITH DRY LINE WEDNESDAY
AFTERNOON AND WILL NEED TO MONITOR FOR POSSIBLE STORMS ACROSS THE
FAR SE PLAINS. AS FOR TEMPS...SHOULD SEE HIGHS FALLING BACK TO
AROUND SEASONAL AVERAGES THROUGH THE PERIOD WITH COOLING ALOFT.
FRIDAY-SATURDAY...COOL AND DRY NORTHWEST FLOW PROGGED TO DEVELOP
BEHIND PASSING TROUGH...KEEPING SLIGHT POPS DIURNAL POPS IN PLACE
ACROSS THE HIGH TERRAIN ALONG WITH TEMPERATURES SLIGHTLY BELOW
AVERAGE INTO THE EARLY WEEKEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1123 PM MDT SAT MAY 25 2013
VFR CONDITIONS ARE EXPECTED AT KCOS...KPUB AND KALS FOR THE NEXT
24 HOURS. BREEZY SOUTH TO SOUTHWEST WINDS ARE EXPECTED AT THE TAF
SITES BY SUNDAY AFTERNOON.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM 11 AM TO 9 PM MDT SUNDAY FOR COZ221-222-
225-227-233-237.
&&
$$
AVIATION...28
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1230 AM EDT SUN MAY 26 2013
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 233 PM EDT SAT MAY 25 2013
A WARM FRONT WILL LIFT NORTHEAST ACROSS CENTRAL INDIANA LATE SUNDAY
THROUGH MONDAY EVENING. THE FRONT AND UPPER LEVEL DISTURBANCES WILL
HELP BRING SHOWERS AND THUNDERSTORMS TO CENTRAL INDIANA THIS
MEMORIAL DAY WEEKEND AND INTO EARLY NEXT WEEK. THE WARM FRONTAL
PASSAGE WILL ALSO BRING A RETURN TO NORMAL TEMPERATURES BY MONDAY
AND ABOVE NORMAL TEMPERATURES IN THE 80S BY TUESDAY. THUNDERSTORM
CHANCES WILL RETURN BY SATURDAY FOLLOWING A DRY MID TO LATE WEEK.
&&
.NEAR TERM /OVERNIGHT/...
ISSUED AT 1012 PM EDT SAT MAY 25 2013
RAIN SHOWERS CURRENTLY ACROSS MUCH OF THE SOUTHWEST HALF OF THE
FORECAST AREA WITH LIGHTER SHOWERS/SPRINKLES FURTHER NORTHEAST.
TEMPS WERE IN THE 50S AT 02Z.
UPPER LEVEL SHORTWAVE WILL TRACK ACROSS THE REGION OVER THE NEXT
FEW HOURS MAINTAINING THE RAIN SHOWERS THROUGH AT LEAST 06Z. THE
GREATEST COVERAGE TO RAINFALL WILL BE SOUTHWEST OF A LAFAYETTE-
INDY METRO-SEYMOUR LINE WHERE DEWPOINTS AND LOW LEVEL MOISTURE ARE
A BIT MORE PLENTIFUL. ONCE THE SHORTWAVE SHIFTS OFF TO THE
SOUTHEAST LATE TONIGHT...EXPECT COVERAGE TO SHOWERS TO DIMINISH
ACROSS MUCH OF THE AREA AND THE CURRENT HRRR SUPPORTS THIS
THINKING. FORECAST LOWS STILL LOOK REACHABLE WITH MANY AREAS
FALLING INTO THE UPPER 40S AND LOWER 50S.
ZONE AND GRID UPDATES OUT.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
ISSUED AT 233 PM EDT SAT MAY 25 2013
MAIN CHALLENGE FOR MEMORIAL DAY WEEKEND THROUGH TUESDAY WILL BE POPS
AS SHOWERS AND THUNDERSTORMS WILL PLACE OUTDOOR ACTIVITIES IN
JEOPARDY ACROSS CENTRAL INDIANA.
MODELS IN GOOD AGREEMENT ON BRINGING A SWATH OF QPF ACROSS CENTRAL
INDIANA ON SUNDAY AS WARM FRONT DRIFTS NORTHEAST TO THE MIDDLE
MISSISSIPPI VALLEY...AND FRONTOGENESIS AT 850 MILLIBARS AND WARM AIR
ADVECTION CONTINUE NORTHEAST OF THE FRONT ACROSS CENTRAL INDIANA.
ALSO...MORE UPPER WAVES WILL MOVE ACROSS AHEAD OF THE APPROACHING AND
WEAKENING UPPER RIDGE. THUS...WILL RAISE POPS TO GOOD CHANCE OR
BETTER WITH LIKELY POPS ALONG AND NEAR A CORRIDOR FROM IND-LAF AFTER
18Z. LOOKING AT MOST UNSTABLE CAPE PROGS...WOULD NOT RULE OUT
THUNDER ESPECIALLY SOUTHWEST OF IND...BUT WILL GO AHEAD AND INCLUDE
ISOLATED THUNDER ACROSS ALL COUNTIES. SUNDAY NIGHT AND MONDAY LOOK
TO BE THE MOST ACTIVE PERIOD AS THE WARM FRONT MOVES THROUGH WITH
HIGHEST POPS FROM IND AND NORTH...WHERE CHANCES WILL BE IN THE
LIKELY CATEGORY. MORE UNSTABLE AIR ALSO ARRIVES WITH THE FRONT...SO
WENT WITH THUNDER ALL ZONES FROM SUNDAY NIGHT ON. POPS WILL BE
DECREASING FROM SOUTH TO NORTH BEHIND THE FRONT BY MONDAY NIGHT WITH
A DRY FORECAST FAR SOUTH ON TUESDAY AS THE UPPER RIDGE MOVES ACROSS
THE OHIO VALLEY.
TEMPERATURES WILL BE CLIMBING EACH DAY AS THE WARM FRONT APPROACHES
AND IN ITS WAKE. BELOW NORMAL TEMPERATURES PER MODEL BLEND AND
CONSALL LOOK GOOD FOR SUNDAY WITH HIGHS ONLY IN THE MID 60S NORTH TO
THE LOWER 70S SOUTH. BY MONDAY WITH THE FRONT MOVING
THROUGH...SHOULD BE A STRONGER TEMPERATURE GRADIENT. HIGHS EXPECTED
TO WARM TO NEAR NORMAL IN THE UPPER 60S NORTHEAST TO THE UPPER 70S
SOUTHWEST. FINALLY...HIGHS WILL BE ABOVE NORMAL BY TUESDAY WITH
CENTRAL INDIANA IN THE WARM SECTOR. AFTERNOON HIGHS IN THE LOWER 80S
PER BLEND LOOK GOOD.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
ISSUED AT 212 PM EDT SAT MAY 25 2013
MODELS ARE CLOSE ENOUGH THAT THE ALLBLEND INITIALIZATION CAN BE USED
FOR MOST ITEMS.
UPPER RIDGE WILL BE IN CONTROL THROUGH MOST OF THE PERIOD...AND THIS
SHOULD KEEP A CAP ON CONVECTION. MODELS CONTINUE TO FLIP-FLOP ON
WHETHER RIDGE WILL BREAK DOWN ENOUGH FOR SOME CONVECTION ON FRIDAY.
RATHER THAN FLIP-FLOP WITH THIS FORECAST...WILL KEEP IT CONSISTENT
AND GO DRY THROUGH FRIDAY NIGHT. RIDGE LOOKS TO BREAK DOWN ENOUGH ON
SATURDAY FOR CHANCE POPS.
UPPER RIDGE WILL ALLOW WARM TEMPERATURES THROUGH THE PERIOD.
&&
.AVIATION /DISCUSSION FOR THE 26/0600Z TAFS/...
ISSUED AT 1230 AM EDT SUN MAY 26 2013
PERSISTENT WIDESPREAD RAIN SHOWERS ARE STILL AFFECTING TAF
SITES...AND WILL CONTINUE TO DO SO FOR DURATION OF TAF PERIOD.
CONDITIONS WILL GENERALLY STAY IN THE VFR CATEGORY...EXCEPT DURING
HEAVIER RAIN SHOWERS WHEN REDUCED VISIBILITIES AND CEILINGS COULD
RESULT IN PERIODS OF MVFR CONDITIONS. NORTHEASTERLY WINDS WILL
SLOWLY VEER TO THE EAST AND THEN SOUTHEAST BY DAYBREAK TODAY.
SUSTAINED SPEEDS WILL BE BETWEEN 5 TO 10 KTS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...MK
NEAR TERM...RYAN
SHORT TERM...MK
LONG TERM....50
AVIATION...TDUD
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 TWIN CITIES/CHANHASSEN MN
357 AM CDT SUN MAY 26 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 356 AM CDT SUN MAY 26 2013
THUNDERSTORMS ARE SLOWLY BUILDING INTO SOUTHWEST AND SOUTH CENTRAL
MN EARLY THIS MORNING AS THE LOW LEVEL MOISTURE TRANSPORT IS SLOWLY
VEERING TO OUR SOUTH. THE WORST OF THE STORMS REMAIN FOCUSED NW-SE
ACROSS KFSD... WHERE UP TO 6 INCHES OF RAIN HAS FALLEN OVERNIGHT.
THE 850MB DEW POINT SATURDAY EVENING FROM THE KOMA RAOB WAS 15 DEG
C.
SHORT TERM MODEL GUIDANCE SUGGESTS THE MOISTURE TRANSPORT FOCUSES
FOR A TIME THIS MORNING ACROSS SOUTH CENTRAL MN WITH MULTIPLE ROUNDS
OF CONVECTION POSSIBLE. EVENING RUNS OF THE HRRR WERE VERY BULLISH
ON HEAVY RAINFALL FOR SOUTH CENTRAL MN THIS MORNING.. BUT MORE
RECENT RUNS HAVE BACKED DOWN. OUR MPXWRF AND THE VARIOUS HOPWRF RUNS
SUGGEST THE CONVECTION WEAKENING DURING THE MORNING AS WELL WITH THE
WORST STAYING ACROSS IA. THIS IS IN PART DUE TO THE LOW LEVEL JET
DIMINISHING SOME OVER US... ALONG WITH THE FACT THAT THE BETTER
GRADIENT OF INSTABILITY REMAINS MORE TO OUR WEST AND SOUTH.
THERE SHOULD BE A SIGNIFICANT DROP IN THE PRECIPITATION COVERAGE AND
INTENSITY BY THIS AFTERNOON OVER SOUTHERN MN. HOWEVER... THE SPCWRF
DOES SHOW SHOWERS DEVELOPING OVER CENTRAL MN DURING THE AFTERNOON IN
WHAT SEEMS TIED TO A MCV FROM THE CONVECTION ONGOING OVER CENTRAL SD
ATTM. THEREFORE... SMALL POPS REMAIN FOR THE MN CWA WITH SMALL POPS
SPREADING INTO WEST CENTRAL WI DURING THE LATE AFTERNOON AND
EVENING. LITTLE CHANGE IN THE HIGH TEMPERATURE TODAY WITH AROUND 60
TO MIDDLE 60S FORECAST.
FOR TONIGHT... MORE THUNDERSTORMS WITH HEAVY RAINFALL ARE EXPECTED
TO DEVELOP TO OUR WEST AND SOUTH. THE LOW LEVEL MOISTURE TRANSPORT
IS FOCUSED NEAR THE I-29 CORRIDOR EARLY IN THE NIGHT AND THEN SHIFTS
INTO OUR CWA ON MONDAY. THE SPC/NSSL/NMM AND ARW WRF/S SHOW THE
WORST OF THE CONVECTION TONIGHT ACROSS SD/NE/IA. AT THIS
POINT...POPS TONIGHT INCREASE FROM LOW CHANCE IN THE EVENING TO
LIKELY BY DAYBREAK MONDAY.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 356 AM CDT SUN MAY 26 2013
BEST ADVICE FOR THE LONG TERM...PACK AN UMBRELLA!
AS HAS BEEN THE CASE FOR THE LAST SEVERAL DAYS...MEDIUM RANGE
MODELS CONTINUE TO SHOW A VERY WET AND ACTIVE PATTERN SETTING UP
ACROSS THE NORTHERN PLAINS/UPPER MS VALLEY THROUGH THE COURSE OF NEXT
WEEK. THERE IS STILL GOOD AGREEMENT WITH AN UPPER RIDGE SETTING UP
ON THE EAST COAST OF THE CONUS...AS DEEP TROUGHING REMAINS IN
PLACE ACROSS THE ROCKIES...BEFORE A CLOSED LOW DEVELOPS OVER THE
NORTHERN PLAINS BY THE END OF THE WEEK. DEEP AND MOIST SW FLOW IN
BETWEEN WILL RESULT IN SEVERAL CHANCES FOR THUNDERSTORMS NEXT
WEEK. AS WE HAVE SEEN IN THE SIOUX FALLS AREA THIS EVENING...
FLOODING...BOTH OF THE FLASH AND AREAL/RIVER VARIETY WILL BE
POSSIBLE...ALONG WITH SEVERE WEATHER. FOR SEVERE WEATHER...TUESDAY
THROUGH FRIDAY LOOK TO PROVIDE OPPORTUNITIES FOR SEVERE
WEATHER...WITH THURSDAY AND FRIDAY AT THIS POINT LOOKING TO HAVE
POTENTIAL FOR MORE SIGNIFICANT...OR AT LEAST WIDESPREAD EVENTS.
A KEY COMPONENT FOR THE STORM POTENTIAL THROUGH THE WEEK WILL BE
FRONTAL...ALONG WITH WHAT LOOKS TO BE A VERY ACTIVE LLJ PLACEMENT.
FOR THE WARM FRONT...IT WILL FINALLY START PUSHING INTO MN ON
MONDAY...LIFTING NORTH THROUGH THE MPX CWA DURING THE DAY. THIS
BOUNDARY WILL THEN STALL OUT ACROSS THE AREA ON TUESDAY AND LOOKS
TO WAFFLE AROUND CENTRAL MN INTO NRN WI THROUGH WEDNESDAY.
THURSDAY WILL BRING WITH IT A DEEP SFC LOW INTO NODAK. THIS WILL
FORCE THE WARM FRONT UP INTO CANADA...BUT BEGIN TO SEND A COLD
FRONT ACROSS THE DAKOTAS. THIS SFC LOW WILL BE SLOW MOVING AS IT
BECOMES OCCLUDED OVER SRN MANITOBA THURSDAY NIGHT...WHICH WILL
PULL THE COLD FRONT THROUGH MN ON FRIDAY.
AS FOR PRECIP CHANCES...THEY WILL BE CLOSELY TIED TO WHERE THE LLJ
DECIDES TO SET UP AT ANY PARTICULAR TIME. THE LLJ WILL BE LIFTING
ACROSS MN WITH THE WARM FRONT ON MONDAY...WITH FAIRLY WIDESPREAD
THUNDERSTORMS EXPECTED TO LIFT NORTHEAST THROUGH THE AREA DURING
MEMORIAL DAY AS A RESULT. AT LEAST THIS IS WHAT DETERMINISTIC RUNS
SHOW HAPPENING MEMORIAL DAY. SOMEWHAT CONSPICUOUSLY...THE CAMS SUCH
AS THE NMM AND ARW WERE KEEPING MONDAY DRY WITH THEIR 26.00
RUNS...THOUGH THE FORCING EXPECTED WITH THE WARM FRONT/LLJ WOULD
SUGGEST THE DETERMINISTIC RUNS ARE MORE BELIEVABLE. FOR MONDAY
NIGHT INTO TUESDAY...THE LLJ ANGLES NORTHEAST ACROSS IOWA INTO THE
GREAT LAKES...SO THIS MAY LEAD TO A LULL IN ACTIVITY TUESDAY...WHEN
THE LOWEST POPS OVER THE NEXT WEEK CAN BE FOUND. LLJ BACKS TO THE
SOUTH TUESDAY NIGHT...BRINGING INCREASED THUNDERSTORM CHANCES BY
LATE TUESDAY NIGHT THAT WILL PERSIST THROUGH FRIDAY...WITH THE LLJ
NOT SHOWING SIGNS OF GETTING SHUNTED OFF TO THE EAST OF THE MPX
AREA UNTIL SATURDAY.
FOR SEVERE WEATHER...CIPS ANALOG IMPACT GUIDANCE INDICATING WE
COULD SEE SEVERE WEATHER BASED ON THE TOP 8 MATCHES FROM MONDAY
RIGHT THROUGH WEDNESDAY...THOUGH PROBABILITIES FOR SEVERE WEATHER
ARE MAXIMIZED FOR THURSDAY AND FRIDAY. ON MONDAY...AN ISOLATED
SEVERE HAIL STORM WILL BE POSSIBLE AS THE WARM FRONT LIFTS
NORTH...BUT THIS ACTIVITY LOOKS TO BE ELEVATED AND PRIMARILY
RESPONSIBLE FOR HEAVY RAINFALL. FOR TUESDAY...BEST LLJ FORCING
WILL BE OFF TO THE SE OF THE MPX CWA...BUT WITH A STATIONARY FRONT
PROGGED TO BE ANYWHERE BETWEEN CENTRAL AND SOUTHERN
MINNESOTA...IF SFC BASED CONVECTION WERE TO GET GOING ALONG THIS
BOUNDARY...THEN ALL FORMS OF SEVERE WEATHER WOULD BE POSSIBLE...AS
INDICATED IN THE DAY 3 SPC CONVECTIVE OUTLOOK. YOU CAN MAKE THE
SAME ARGUMENT FOR THE SEVERE WEATHER THREAT ON WEDNESDAY...AS THE
BOUNDARY REMAINS OVER MN...BUT THE ATMOSPHERE IS RELOADING ACROSS
THE DAKOTAS. THURSDAY AND FRIDAY AT THIS POINT ARE THE INTERESTING
DAYS WHERE EVERYTHING LOOKS TO HAVE TO POTENTIAL TO COME IN LINE.
THURSDAY ACROSS MOST OF MN...AND FRIDAY MORE ERN MN INTO WI. BOTH
DAYS...THE GFS/ECMWF SHOW H85 WINDS INCREASING TO OVER 40 KTS OUT
AHEAD OF THE COLD FRONT...HELPING PUSH SFC DEWPS INTO THE UPPER
60S. WIND SHEAR BOTH DAYS THOUGH LOOKS TO BE MAINLY
UNIDIRECTIONAL AND RUNNING PARALLEL TO THE FRONT...WHICH WOULD
FAVOR ACTIVITY BECOMING LINEAR QUITE QUICKLY...ALONG WITH
INCREASING THE HEAVY RAIN/FLOOD POTENTIAL.
AS FOR THAT FINAL HAZARD OF FLOODING...THE ECMWF/GFS CONTINUE TO
PAINT 3 TO 4 INCHES OF RAIN ACROSS JUST ABOUT THE ENTIRE MPX CWA
THROUGH THE COURSE OF NEXT WEEK...WITH 6 PLUS INCH AMOUNTS STILL
INDICATED FOR MUCH OF IOWA. THE MAJORITY OF THAT RAIN WITH THE
26.00 RUNS COMES FROM MONDAY AND AGAIN THURSDAY AND FRIDAY. HAVE
HELD OFF ON ANY FLASH FLOOD WATCHES AT THIS POINT...BUT MONDAY
COULD POSE ISSUES AS THE WARM FRONT LIFTS NORTH. WILL CONTINUE
WITH THE FLOOD MENTION IN THE HWO.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1105 PM CDT SAT MAY 25 2013
WHILE KRWF-KAXN-KSTC HAVE ALL GONE DOWN TO MVFR...EASTERN SITES
HAVE YET TO DROP DOWN. WAS THINKING KMSP WOULD HAVE DROPPED DOWN
TO MVFR BY THIS POINT...WHAT WITH SITES JUST W AND S HAVING GONE
THAT LOW...BUT IT SHOULD BE WITHIN THE FIRST FEW HOURS OF THE
26/06Z TAF THAT CONDS DROP TO MVFR. CIGS THEN REMAIN AT MVFR THRU
MOST OF THE DAY...THEN A FEW BREAKS IN THE LOWER /2000-3000 FT/
DECK SCATTER OUT TO ALLOW FOR VFR CONDS BEFORE MVFR CIGS FILL BACK
INTO THE AREA. ONLY SITE TO BE HIT HARD WITH PRECIP IN THIS
ISSUANCE IS KRWF...WHICH IS IN CLOSEST PROXIMITY TO THE LINGERING
SFC FNT AND ITS ASSOCIATED CONVECTION THIS MRNG. SHWRS/TSTMS WILL
GRADUALLY SPREAD FROM SWRN MN INTO THE REST OF CENTRAL-SRN MN THRU
THE DAY TDA...THEN SLOWLY INTO WRN WI TNGT INTO EARLY MON. CONDS
TO GRADUALLY DETERIORATE AS PRECIP MOVES IN...BUT TIMING ISSUES
AMONG THE SHORT-TERM MODELS DO NOT GIVE A LOT OF CONFIDENCE ATTM.
WINDS TO REMAIN BETWEEN 120-140 WITH SPEEDS AOA 10 KT...INCLUDING
FREQUENT GUSTS ABOVE 20 KT DURG THE DAY TMRW.
KMSP...VFR CONDS TO START WILL EVENTUALLY DROP BELOW MVFR LEVELS
AROUND 09Z...THEN STAY THERE THRU MUCH OF THE DAY. AM NOT
EXPECTING CIGS TO DROP BELOW 2 KFT. CEILINGS MAY EVEN RISE ABOVE 3
KFT EARLIER THAN ADVERTISED...BUT CONFIDENCE IS HIGH THAT MVFR
CIGS RETURN BY LATE EVENING. PRECIP LOOKS TO HOLD OFF TO THE SW OF
THE TERMINAL THRU THE DAY...THEN PRECIP SLOWLY MOVES INTO THE AREA
DURG THE EVE HRS. WILL START OFF THE PRECIP LIGHT THEN BRING IN
HEAVIER PRECIP TMRW NIGHT...WHICH LINES UP WITH MODEL PROGS OF
HAVING HEAVIER AND MORE WIDESPREAD TMRW NIGHT RATHER THAN DURG THE
DAY. COULD EASILY HAVE TSTMS...BUT HAVE STARTED THINGS MORE
OPTIMISTICALLY AND WILL ALLOW LATER TAF ISSUANCES SEE HOW
CONDITIONS DEVELOP.
/OUTLOOK FOR KMSP/
MON...CHC MVFR OR LOWER CIGS. SHRA/TSRA LIKELY. WINDS SE 10-15 KTS.
TUE...CHC MVFR OR LOWER CIGS. CHC SHRA/TSRA. WINDS SSE 5-10 KTS.
WED...CHC MVFR OR LOWER CIGS. CHC SHRA/TSRA. WINDS S 5-10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...RAH
LONG TERM...MPG
AVIATION...JPC
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
340 AM CDT SUN MAY 26 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 331 AM CDT SUN MAY 26 2013
YET ANOTHER COMPLICATED FORECAST FOR TODAY. MOST OF THE CWA IS
VOID OF PRECIPITATION AT THE CURRENT TIME. THE CLOSEST ORGANIZED
AREA OF PRECIPITATION IS A NARROW ELONGATED AREA OF SHOWERS AND
THUNDERSTORMS STRETCHING FROM NORTH CENTRAL IA INTO WEST CENTRAL
IL. THIS ACTIVITY IS LOCATED WITHIN THE GRADIENT OF ELEVATED
INSTABILITY AND IS ASSOCIATED WITH WEAK LOW LEVEL WAA AND MOISTURE
CONVERGENCE VIA A BROAD SWLY LLJ. THIS ACTIVITY MAY SKIRT THE FAR
EASTERN PART OF THE CWA IN THE POST-DAYBREAK PERIOD...OTHERWISE I
THINK THROUGH MID MORNING THAT ANY ACTIVITY WILL BE RATHER
ISOLATED IN COVERAGE. THIS SHOULD CHANGE BEGINNING AROUND MIDDAY
WHEN SCATTERED SHOWERS AND THUNDERSTORMS SHOULD BEGIN TO DEVELOP
...WITH A CONTINUED UPSWING IN COVERAGE THRU THE AFTERNOON IN
RESPONSE TO HEATING/INCREASING INSTABILITY AND INCREASING ASCENT
VIA A DISTURBANCE DROPPING SEWD OUT OF IA FROM THE RIDGE CREST.
THE GREATEST COVERAGE IS EXPECTED TO BE ALONG AND WEST OF THE MS
RIVER...SANS SE MO. DURING THE LATE AFTERNOON INTO THE EARLY
EVENING THERE ARE 2 POSSIBLE SCENARIOS WHICH I ENVISION. THE FIRST
SCENARIO HAS AN MCS EVOLVING ACROSS NE MO/WC IL DUE TO UPSCALE
GROWTH FROM ALL THE SCATTERED CONVECTION DUE TO MERGERS AND COLD
POOL INTERACTION ENHANCED BY THE SSWLY LLJ AND THE DISTURBANCE
ALOFT. THE OTHER PLAUSIBLE SCENARIO IS THE CURRENT MCS OVER NW
IA/SE SD WILL TRACK SEWD TODAY AND THEN MERGE WITH THE
AFOREMENTIONED SCATTERED ACTIVITY IN NE MO/WC IL DURING THE LATE
AFTERNOON. THE END RESULT IN EITHER CASE IS A SEWD MOVING MCS
WHERE THE APEX TRACKS CLOSE TO THE MS RIVER DURING THE EVENING.
THERE COULD ALSO BE ADDITIONAL DEVELOPMENT TONIGHT ON THE TRAILING
FLANK OF THE MCS ACROSS ERN MO DUE TO LIFT VIA THE SWLY
LLJ/MESOSCALE BOUNDARY. IF THIS DOES INDEED OCCUR THERE COULD BE
HEAVY RAIN POTENTIAL...BUT THERE ARE A LOT OF IFS DUE TO MESOSCALE
FACTORS WHICH MUST COINCIDE. THE HRRR AND LAST FEW RUNS OF THE
NCAR 3KM ARW WRF LEND CREDENCE TO THESE SCENARIOS DISCUSSED ABOVE.
GLASS
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 301 AM CDT SUN MAY 26 2013
THERE ARE INDICATIONS IN THE QPF AND MASS FIELDS FROM THE MODELS
ALONG WITH THE AFOREMENTIONED CONVECTION ALLOWING NCAR ARW WRF
THAT AT LEAST THE AREA ALONG AND NORTH OF I-70 COULD BE QUITE ACTIVE
LATE MONDAY MORNING/AFTERNOON. YET ANOTHER DISTURBANCE WILL BE
TRACKING SEWD THRU THE AREA...THE SYNOPTIC SCALE WARM FRONT WILL
BE TRYING TO RETREAT NORTHWARD AND THERE IS POTENTIAL FOR REMNANT
MESOSCALE BOUNDARIES TO FOCUS LIFT - BOTH RESIDENT FROM OVERNIGHT
AND ASSOCIATED WITH DECAYING MCS ACTIVITY MOVING SEWD FROM THE
CENTRAL PLAINS. THE AIR MASS SHOULD ALSO BE MORE UNSTABLE.
IT STILL LOOKS LIKE BY LATE MONDAY NIGHT AND INTO TUESDAY THAT THE
UNSETTLED PATTERN WILL CALM DOWN DUE TO PROGRESSION OF THE UPPER
PATTERN WITH THE UPPER RIDGE SHIFTING INTO THE ERN U.S. AND THE
NORTHWARD RETREAT OF THE WARM FRONT. THIS WILL RESULT IN WARMER
TEMPERATURES AND MAINLY DRY CONDITIONS. AMPLIFICATION OF THE FLOW
ALOFT SHOULD KEEP TEMPERATURES ABOVE NORMAL...WITH A RENEWED
THREAT OF SHOWERS AND THUNDERSTORMS DURING THE LATER PART OF THE
WEEK INTO THE EARLY WEEKEND AS THE WESTERN TROF SHIFTS INTO THE
NATIONS MIDSECTION.
GLASS
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1142 PM CDT SAT MAY 25 2013
THUNDERSTORMS CONTINUE TO BE THE PRIMARY FOCUS FOR THIS CYCLE. NOW
WATCHING SOME LIGHT SHOWERS DEVELOP ACROSS WEST CENTRAL ILLINOIS
STRETCHING SOUTHEAST INTO PARTS OF SOUTH CENTRAL ILLINOIS. EXPECT
THIS DEVELOPMENT TO CONTINUE AND BUILD SOUTHWARD OVERNIGHT. SHORT
RANGE MODEL GUIDANCE NEVER REALLY DEVELOPS ANYTHING PARTICULARLY
HEAVY OR ORGANIZED...SO HAVE NOT REALLY CHANGED THE VCTS FORECAST
IN MOST OF THE TAFS. EXPECT VFR FLIGHT CONDITIONS TO PREVAIL
OUTSIDE OF ANY SHOWERS OR STORMS.
GUIDANCE IS PRETTY INSISTENT THAT THERE WILL BE ANOTHER ROUND OF
THUNDERSTORMS ON SUNDAY AFTERNOON/EVENING. NOT SURE HOW STRONG
THIS ROUND OF STORMS WILL BE. SOME MODELS SUGGEST ONLY SCATTERED
AFTERNOON THUNDERSTORMS...WHILE OTHER MODELS HAVE WIDESPREAD
STORMS WITH HEAVY RAIN AND POSSIBLY STRONG WIND GUSTS. IF THE
SECOND SCENARIO IS MORE ACCURATE...THUNDERSTORMS WILL LAST WELL
INTO THE EVENING...POTENTIALLY PAST 06Z SUNDAY NIGHT.
SPECIFICS FOR KSTL...
THUNDERSTORMS CONTINUE TO BE THE PRIMARY FOCUS FOR THIS CYCLE.
EXPECT LIGHT SHOWERS NOW DEVELOPING OVER WEST CENTRAL INTO SOUTH
CENTRAL ILLINOIS TO BECOME MORE WIDESPREAD. SHORT RANGE MODEL
GUIDANCE NEVER REALLY DEVELOPS ANYTHING PARTICULARLY HEAVY OR
ORGANIZED...SO HAVE NOT REALLY CHANGED THE VCTS FORECAST. EXPECT
VFR FLIGHT CONDITIONS TO PREVAIL OUTSIDE OF ANY SHOWERS OR
STORMS.
GUIDANCE IS PRETTY INSISTENT THAT THERE WILL BE ANOTHER ROUND OF
THUNDERSTORMS ON SUNDAY AFTERNOON/EVENING. NOT SURE HOW STRONG
THIS ROUND OF STORMS WILL BE. SOME MODELS SUGGEST ONLY SCATTERED
AFTERNOON THUNDERSTORMS...WHILE OTHER MODELS HAVE WIDESPREAD
STORMS WITH HEAVY RAIN AND POSSIBLY STRONG WIND GUSTS. IF THE
SECOND SCENARIO IS MORE ACCURATE...THUNDERSTORMS WILL LAST WELL
INTO THE EVENING...POTENTIALLY PAST 06Z SUNDAY NIGHT.
CARNEY
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1156 PM CDT Sat May 25 2013
.UPDATE...
Issued at 950 PM CDT SAT MAY 25 2013
With convection struggling to develop along the frontal boundary
across far northern Missouri this evening, have opted to reduce the
chance of precipitation significantly over the next few hours. Some
development along an elevated boundary stretching from southeast
through central Iowa will be possible over the next few hours and
could build southwest into the forecast area, so have preserved
increased PoPs across our far northeast during the early morning
hours. Convection currently over north central Kansas may also push
eastward into the area after 09z, so have brought in slightly higher
chances for showers and thunderstorms in the northwest during this
period.
&&
.SHORT TERM...(This Evening through Sunday)
Issued at 345 PM CDT SAT MAY 25 2013
Very few changes were needed to the forecast through tomorrow. Based
on latest high res models, radar, and satellite trends it appears,
other than a stray shower across the MO/IA border, the CWA should
remain dry this evening. Later tonight a small cluster of storms is
progged to work in from the west, but the latest HRRR depicts a
weaker system than what much of the NRN third of the CWA experienced
early this morning. At this time I have an overnight precip forecast
that favors the northern half of the CWA with higher chance pops
compared to lower chances to the south. As for tomorrow, more of
the same with lingering scattered morning showers and weak
thunderstorms with perhaps redevelopment in the afternoon.
Temperature wise the CWA will remain mild and rather muggy as
compared to the past several days under partly to mostly cloudy
skies.
.LONG TERM...(Sunday Night through Saturday)
Issued at 345 PM CDT SAT MAY 25 2013
The potential for wet weather looks to bracket either end of the
work week, though there will be plenty of dry days in between.
Shortwave ridge will be dominating the Central Plains as Memorial
Day dawns, with nocturnal thunderstorm activity likely lingering
through the morning hours. In general, operational and ensemble
models continue to advertise that this modest ridge will stay in
place across the Plains States through Tuesday, when the west CONUS
trough will finally begin to shift east. As the trough begins to
move into the Plains the storm track will shift farther north which
should give most locations in our forecast areas a break from the
rain chances. However, given the negative tilt to the trough as it
shifts into the Plains, and the general synoptic pattern, thoughts
are that storms will not only return tot he forecast, but severe
weather may plague the region by the end of the work week.
Currently, the best potential for storms looks to be Thursday night
and Friday night as the nocturnal jet cranks up ahead of the west
CONUS trough.
Otherwise, with the prevailing storm track, and by extension the
prevailing westerlies, remaining to the north of Kansas and Missouri
through the work week we expect temperatures to rise to a category
or two above normal through the week.
&&
.AVIATION...(For the 06Z TAFS through 06Z Sunday Night)
Issued at 1155 PM CDT SAT MAY 25 2013
A cluster of thunderstorms across northern Kansas and southern
Nebraska continue to move eastward tonight. Models continue to show
these thunderstorms weakening as they approach the terminals however
there is some concern that these storms will see an uptick in
coverage and intensity as a 30-35kt nocturnal southerly LLJ begins to
get cranked up. Have left the TAF dry for now however if that line
holds together there will be the chance for diminished showers and
thunderstorms to move into the terminals by around 12Z. Otherwise,
conditions should remain VFR as expect bkn clouds around 5-6kft
through the overnight. GFS MOS and LAMP guidance as well as NAM BUFR
soundings are still trying to introduce MVFR cigs tomorrow morning
around 11Z however still think the boundary layer is too moist.
Did however include a sct deck around 2500ft around 11Z. Expect sct-
bkn cigs around 4kft through the afternoon tomorrow. There will be
the chance for afternoon thunderstorms however timing and placement
on these storms continue to be nebulous as it may be contingent on
any leftover outflow boundaries from tonights activity. Winds during
the TAF period will be out of the SSE around 8-15kts.
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.
&&
$$
UPDATE...Laflin
SHORT TERM...Pietrycha
LONG TERM...Cutter
AVIATION...73
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1145 PM CDT SAT MAY 25 2013
.UPDATE...
IT APPEARS THAT MAIN AREA OF CONVECTION WILL SETUP NORTH OF THE
NORTHWARD LIFTING WARM FRONT. THESE SHOULD TEND TO LIFT NORTHEAST
OVERNIGHT...AND MAY EVEN MOVE OUT OF OUR AREA. HELD ONTO SOME
CHANCE IN OUR SOUTHERN ZONES.
MILLER
&&
.AVIATION...
06Z TAFS FOR KOMA...KLNK AND KOFK.
THOUGHT CHANCES WERE TOO LOW TO INCLUDE ANY MENTION OF TSTMS AT
ANY OF THE TAF POINTS OVERNIGHT...AND ALSO FELT CHANCES WERE LOW
ENOUGH TO LEAVE A PROB30 GROUP OUT FOR SUNDAY AFTERNOON.
OVERNIGHT...CEILINGS SHOULD LOWER A BIT...INTO MAINLY THE MVFR
CATETORY BUT POSSIBLY TO IFR. IFR CONDITIONS WOULD BE MOST LIKELY
09Z-14Z. CEILINGS SHOULD TEND TO IMPROVE TOWARD VFR BY LATE
MORNING OR EARLY AFTERNOON.
MILLER
&&
.PREV DISCUSSION... /ISSUED 311 PM CDT SAT MAY 25 2013/
DISCUSSION...
ALTHOUGH TIMING OF HIGHEST CONCENTRATION OF ANY CONVECTION IS THE
MAIN CHALLENGE FOR ANY GIVEN PERIOD WELL INTO NEXT WEEK...PATTERN
LOOKS TO REMAIN ACTIVE WITH PRECIP CHANCES GOOD IF NOT LIKELY MOST
AREAS MOST EVENINGS/OVERNIGHT PDS.
AT 19Z SURFACE BOUNDARY EXTENDED FROM JUST N OF FNB TO JUST SW OF
OLU/BVN WITH RESIDUAL COOL OUTFLOW FROM MORNING CONVECTION
REINFORCING FRONT. CONVERGENCE NEAR BOUNDARY HAD INCREASED CU
FIELD WCNTRL ZONES AND LATEST RAP MESO ANALYSIS PLACED AXIS OF
2000-3000 J/KG ML CAPE ACROSS THAT AREA WITH LITTLE/NO CIN. SO
THERE REMAINS SOME POSSIBILITY OF CONVECTION DEVELOPING NEAR/N OF
THIS BOUNDARY EARLY THIS EVENING...ESPECIALLY AS ANY SUBSIDENCE
EFFECTS OF DEPARTING MCV FROM EARLIER CONVECTION GETS FARTHER
REMOVED. LATER THIS EVENING/OVERNIGHT HIGH PLAINS CONVECTION WILL
PROBABLY MAKE A RUN TOWARD/INTO FA...POSSIBLY CONSOLIDATING MORE
ACROSS NRN ZONES AIDED BY RR ENTRANCE REGION OF WEAK UPPER JET
SEGMENT. HOWEVER...CAN/T RULE OUT ACTIVITY FARTHER S AS WELL SINCE
BOUNDARY MAY NOT MOVE MUCH TONIGHT. LOW LEVEL JET DOES STRENGTHEN
SOME INTO FRONT OVERNIGHT...BUT STRONGEST/MORE CONVERGENT AREA NOT
NECESSARILY FOCUSED ACROSS THE FORECAST AREA...SO CONFIDENCE ON
WIDESPREAD HEAVY RAINFALL NOT VERY GOOD. THAT SAID...SMALL AREA OF
NRN IA ZONES DID PICK UP 1-2+ INCHES OF RAIN LAST NIGHT AND THAT
AREA APPEARS TO HAVE THE HIGHEST CHANCE OF SIGNIFICANT RAINS
TONIGHT AS MOISTURE REMAINS PLENTIFUL WITH PWATS AROUND 1.5
INCHES. THUS ISSUED A SMALL FLASH FLOOD WATCH NE OF OMAHA TO MATCH
UP WITH DMX WHERE HEAVIER RAIN WAS MORE WIDESPREAD.
DECREASED POPS DIURNALLY ON SUNDAY LIKE TODAY ALTHOUGH IT WAS
NOTED THAT FOR SEVERAL RUNS NOW NAM HAD DEVELOPED A SMALL MCS AND
DROPPED IT SE ACROSS FA DURING THE AFTERNOON. FORECAST WAS NOT
BASED ON THAT SCENARIO. ALSO MODELS HINTING AT MORE LOW LEVEL
MOISTURE WITH LOW CLOUDS POSSIBLY LINGERING INTO THE AFTERNOON.
THUS INCREASED SKY COVER. IF CLOUDS HOLD ALL DAY CONVECTIVE
DEVELOPMENT COULD BE ALTERED AS WELL AS HIGH TEMPERATURES.
OTHERWISE...LIKELY POPS MANY AREAS AGAIN WERE MENTIONED SUN NIGHT.
MONDAY POSSIBLY A VERY SIMILAR SCENARIO...ALTHOUGH FINER DETAILS
PROBABLY IMPACTED BY PREVIOUS PERIODS CONVECTION BOTH DAYS.
SOME INDICATION BY MODELS THAT A FRONT...POSSIBLY AIDED BY
OVERNIGHT CONVECTION...WILL PUSH S INTO NRN ZONES ON TUESDAY AS A
STRONGER WAVE EJECTS ACROSS CANADIAN PRAIRIE. COOLING AT H85
MINIMAL FOR THAT AREA...BUT NE WINDS AND POSSIBLE LOW CLOUDS
COULD KEEP MAX TEMPS COOLER AND THIS COULD NEED ATTENTION IN LATER
FORECASTS. OTHERWISE...THIS BOUNDARY AND UPPER TROUGH BEGINNING TO
APPROACH AREA WILL KEEP AREA ACTIVE TUESDAY/TUE NGT. WEDNESDAY
COULD POSSIBLY BE MORE OF A LULL WITH WARMER TEMPERATURES BEFORE
STRONGER ENERGY PUNCHES ACROSS CNTRL PLAINS WED NGT/THURSDAY
INCREASING COVERAGE/CHCS AGAIN. ALTHOUGH SEVERE POTENTIAL WILL
EXIST INTO TUESDAY...THIS STRONGER TROUGH COULD BRING A HEIGHTENED
RISK OF SVR WEATHER TO AREA LATE NEXT WEEK.
CHERMOK
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...FLASH FLOOD WATCH UNTIL 7 AM CDT SUNDAY FOR IAZ043-055-056.
&&
$$
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1210 AM CDT SUN MAY 26 2013
.DISCUSSION...
EXPECT MVFR CEILINGS TO DOMINATE WEST CENTRAL TEXAS BY SUNRISE
TOMORROW MORNING. AVIATION BELOW HAS MORE INFORMATION.
&&
.AVIATION...
MODELS THIS CYCLE PREDICT MVFR CEILINGS WILL COVER WEST CENTRAL
TEXAS BY 12Z. SATELLITE IR LOOP SHOWS STRATUS ALREADY INVADING OUR
NORTHWEST HILL COUNTRY COUNTIES AND OUR SOUTHERN HEARTLAND.
FARTHER NORTH...HIGHER CLOUDS HAVE MASKED SOME OF THE CONCHO
VALLEY AND BIG COUNTRY. WHAT REMAINS UNMASKED IN THOSE TWO AREAS
SHOWS STRATUS IS NOT DEVELOPING THERE LIKE IT IS FARTHER SOUTH
ACROSS WEST CENTRAL TEXAS. SO...I WILL LIKELY ADJUST THE ONSET
TIMING OF MVFR CEILINGS FOR THE ABILENE AND SAN ANGELO TERMINALS.
OTHERWISE...I WILL LIKELY NOT MAKE ANY MAJOR ADJUSTMENTS TO THE
OTHER THREE TERMINALS. ALSO...MODELS THIS CYCLE RETURN VFR
CEILINGS TO WEST CENTRAL TEXAS BY 18Z TOMORROW.
AS FOR CONVECTION...THE LINE OF SHOWERS AND THUNDERSTORMS
APPROACHING FROM THE WEST MAY CONTINUE LONG ENOUGH TO MOVE INTO
THE SAN ANGELO AREA SOMETIME AROUND 06Z TO 07Z. SO...I WILL LIKELY
ADD A TEMPO GROUP FOR THUNDER IN THE SAN ANGELO TERMINAL FOR A
COUPLE HOURS.
HUBER
&&
.PREV DISCUSSION... /ISSUED 1120 PM CDT SAT MAY 25 2013/
UPDATE...
FORECAST HAS BEEN UPDATED FOR POPS...WEATHER AND SKY CONDITION
OVERNIGHT. SEE DISCUSSION.
DISCUSSION...
HAVE BEEN MONITORING THE PROGRESS OF A MESOSCALE CONVECTIVE
SYSTEM MOVING EAST-SOUTHEAST ACROSS WEST TEXAS. ALTHOUGH TOPS
ARE WARMING ON INFRARED SATELLITE IMAGERY...THE SYSTEM IS STILL
HOLDING STRONG AND APPROACHING OUR WESTERN BORDER COUNTIES.
MOVEMENT OF CONVECTION ALONG THE LEADING EDGE IS SOUTHEAST NEAR
40 KT. EXPECT THIS MCS TO EVENTUALLY DISSIPATE OVERNIGHT WHILE
MOVING SOUTHEAST ACROSS OUR AREA. BASED ON RADAR AND SATELLITE
TRENDS...HAVE UPDATED THE FORECAST PRODUCTS FOR WEATHER/POPS AND
SKY CONDITION. CARRYING THE HIGHEST POPS ALONG OUR WESTERN
COUNTIES...TRAILING OFF TO BELOW 15 PERCENT ACROSS OUR FAR EASTERN
AND SOUTHEASTERN COUNTIES. ADDITIONAL UPDATES WILL BE ISSUED AS
NEEDED OVERNIGHT.
PREV DISCUSSION... /ISSUED 630 PM CDT SAT MAY 25 2013/
DISCUSSION...
EXPECT STRATUS TO BRING MVFR CEILINGS BACK TO WEST CENTRAL TEXAS
DURING THE NEXT 6 HOURS. AVIATION BELOW HAS DETAILS.
AVIATION...
MODELS DATA INDICATE STRATUS WILL RETURN TO WEST CENTRAL TEXAS
TONIGHT AND PERSIST UNTIL AROUND NOON TOMORROW. THE LATEST RUC 925
MB RELATIVE HUMIDITY AND WIND FIELD DATA INDICATE STRATUS WILL
RETURN TO WEST CENTRAL TEXAS...FROM THE EAST AND
SOUTHEAST...BEGINNING AROUND 03Z. BY 06Z TONIGHT...PLAN FOR MVFR
CEILINGS TO DOMINATE WEST CENTRAL TEXAS. MOS GUIDANCE DATA FROM
THE GFS INDICATE MVFR CEILINGS AROUND 1500 FEET ABOVE GROUND LEVEL
AT ALL 5 TERMINALS. THE NAM BASED GUIDANCE IS MORE AGGRESSIVE AND
PREDICTS IFR CEILINGS AROUND 700 FEET ABOVE GROUND LEVEL. I
DECIDED TO CONTINUE WITH A FORECAST FAVORING THE GFS
SOLUTION...MAINLY BASED ON PERSISTENCE. AS WAS THE CASE
TODAY...LOOK FOR VFR CEILINGS TO RETURN TO WEST CENTRAL TEXAS
AROUND NOON TOMORROW.
HUBER
PREV DISCUSSION... /ISSUED 501 PM CDT SAT MAY 25 2013/
UPDATE...
FORECAST IS BEING UPDATED FOR POPS...QPF AND SKY CONDITION. SEE
DISCUSSION.
DISCUSSION...
SCATTERED SHOWERS WHICH WERE OVER THE EASTERN THIRD OF WEST CENTRAL
TEXAS EARLIER TODAY HAVE SINCE MOVED OUT OF THE AREA OR DISSIPATED.
RADAR LATE THIS AFTERNOON SHOWS NO ADDITIONAL SHOWER OR THUNDERSTORM
DEVELOPMENT...BUT A SLIGHT CHANCE REMAINS GIVEN THE MOIST AND
UNSTABLE AIRMASS STILL IN PLACE. WITH THE UPPER TROUGH AXIS MOVING
FARTHER AWAY FROM OUR AREA AND ACROSS EAST TEXAS...AND WITH THE
CONVECTIVE ACTIVITY DIURNALLY DRIVEN...EXPECT THE RAIN CHANCE IN
WEST CENTRAL TEXAS TO END BY OR BEFORE 9 PM. HAVE ADJUSTED THE
21Z-00Z WEATHER GRID TO REFLECT THE AFOREMENTIONED TRENDS...AND HAVE
ENDED THE RAIN CHANCE AFTER 02Z. THE GFS AND NAM BOTH SUGGEST LOW
CLOUD DEVELOPMENT NORTHWEST INTO OUR AREA LATE TONIGHT AND EARLY
SUNDAY MORNING...IN MOIST SOUTHEASTERLY BOUNDARY LAYER FLOW. HAVE
ADJUSTED THE SKY CONDITION GRIDS TO REFLECT THIS SCENARIO WITH
INCREASING CLOUDINESS TOWARD MORNING...TO ROUGHLY THE INTERSTATE 20
CORRIDOR. EXPECT THE LOW CLOUD FIELD TO ERODE BY MID TO LATE SUNDAY
MORNING. HAVE ALSO MADE DOWNWARD ADJUSTMENTS TO THE QPF GRIDS FROM
21Z-00Z. WITH LOW CONFIDENCE IN MEASURABLE PRECIPITATION OCCURRING
TONIGHT...HAVE DROPPED THE QPF GRIDS TO ZERO. UPDATED FORECAST
PRODUCTS WILL BE OUT SHORTLY.
PREV DISCUSSION... /ISSUED 341 PM CDT SAT MAY 25 2013/
SHORT TERM...
EARLY THIS AFTERNOON...UPPER TROUGH AXIS IS LOCATED JUST EAST OF
THE FORECAST AREA WITH ASSOCIATED RAINFALL AND THUNDERSTORMS
OCCURRING FROM THE CENTRAL TEXAS GULF COAST NORTH OVER MUCH OF
EAST TEXAS. WITH THE CLOSE PROXIMITY OF THE UPPER LOW TO OUR
CWA...WILL MAINTAIN A SLIGHT CHANCE OF SHOWERS AND ISOLATED
THUNDERSTORMS THROUGH THE NIGHT. AS THE UPPER TROUGH CONTINUES TO
MOVE EAST DURING THE DAY TOMORROW...AN UPPER RIDGE WILL BUILD OVER
THE OUR AREA FROM THE WEST...BRINGING AN END TO OUR RAINFALL
CHANCES. AFTER SUNDAY MORNING LOWS GENERALLY IN THE MID 60S...
AFTERNOON HIGHS ON SUNDAY WILL BE WARMER THAN TODAY...LOWER 90S VS
LOW TO MID 80S.
15
LONG TERM...
THE LONG TERM PORTION OF THE FORECAST WILL BE HIGHLIGHTED BY
PERSISTENT STRONG SOUTHERLY FLOW...OVERNIGHT AND MORNING
STRATUS...AND MIDWEEK PRECIPITATION CHANCES.
THE WEST COAST TROUGH IS PROGGED TO DEEPEN EARLY NEXT WEEK AS THE
SHORTWAVE TROUGH CURRENTLY LOCATED SOUTH OF THE ALEUTIANS MOVES
INTO THE PACNW. WE WILL SEE INCREASING SOUTHWEST FLOW ALOFT WHICH
WILL BOTH ENHANCE THE ELEVATED MIX LAYER /EML/ AND SUPPORT LEE
CYCLOGENESIS. THE LATTER WILL PROVIDE BRISK SOUTH WINDS THROUGHOUT
THE DURATION OF THE FORECAST PERIOD...WITH DAYTIME WIND SPEEDS OF
15-25 MPH AREAWIDE. A STRONG NOCTURNAL LOW LEVEL JET WILL KEEP
GUSTS IN THE FORECAST DURING THE OVERNIGHT HOURS WITH THE
STRONGEST WINDS FOUND ACROSS THE CONCHO VALLEY AND BIG COUNTRY.
THESE SOUTH WINDS WILL PROVIDE A STEADY STREAM OF GULF MOISTURE
INTO THE AREA...KEEPING DEWPOINTS GENERALLY IN THE LOWER 60S AND
PUSHING OVERNIGHT LOWS INTO THE UPPER 60S AND LOWER 70S THROUGH
THE WEEK. THESE BREEZY CONDITIONS MAY BE TEMPORARILY INTERRUPTED
BY CONVECTIVE OUTFLOW BUT I WILL GET MORE INTO THAT IN A BIT.
I EXPECT DRY CONDITIONS THROUGH MONDAY...ALTHOUGH SOME DIURNAL
CONVECTION TO OUR WEST MAY TRY TO SNEAK INTO THE WESTERN ZONES
MONDAY EVENING. THAT SAID...THE STEERING FLOW WILL KEEP THE BEST
CHANCES TO OUR NORTH AND WEST. OTHERWISE...THE CAP LOOKS TO HOLD
AND KEEP A LID ON THE CONVECTIVE POTENTIAL. TEMPS ON MONDAY ARE
EXPECTED TO RANGE FROM THE UPPER 80S TO LOWER 90S ACROSS MOST OF
WEST CENTRAL TX.
PRECIPITATION STILL DO NOT LOOK ALL THAT PROMISING ON TUESDAY DUE
TO THE STRENGTH OF THE EML. THAT SAID...I DID INCLUDE A SLIGHT
CHANCE OF THUNDERSTORMS GENERALLY WEST OF A SONORA...TO WINTERS...
TO HASKELL LINE TO ACCOUNT FOR THE EASTWARD DRIFT ON CONVECTION
OVER WEST TX. THE BEST RAIN CHANCES APPEAR TO OCCUR ON WEDNESDAY.
THE MEDIUM RANGE GUIDANCE IS DEPICTING A NEGATIVELY TILTED
SHORTWAVE TROUGH EJECTING INTO THE SOUTHERN PLAINS BY WEDNESDAY
AFTERNOON. THEY DO DIFFER IN THE LOCATION OF THE STRONGEST
FORCING...WITH THE GFS FAVORING THE CENTRAL HIGH PLAINS AND THE
ECMWF LOOKING FARTHER SOUTH TOWARD WEST TX. EITHER WAY...SYNOPTIC
SCALE FORCING WILL WORK ON THE EML...LIFTING AND COOLING THE LAYER
TO ERODE THE CAP. THE BIGGEST QUESTION IS HOW FAR SOUTH THIS
ASCENT REACHES. THE SEVERE POTENTIAL WILL EXIST GIVEN THE STEEP
MID LEVEL LAPSE RATES...STRONG INSTABILITY AND MORE THAN ADEQUATE
DEEP LAYER SHEAR. THE BIG QUESTION /AS IS USUALLY THE CASE/ IS THE
CAP.
THUNDERSTORM CHANCES LINGER ON THURSDAY BUT THE STRONGEST FORCING
LOOKS TO MOVE EAST BY THURSDAY. MODEL CONSENSUS SHOWS A DEEP...
BROAD TROUGH OVER THE WESTERN 2/3 OF THE CONUS WITH STRONG WEST
SOUTHWEST FLOW OVER WEST TX. WE MAY BEGIN TO SEE THE DRYLINE DRY
TO MIX EAST LATE IN THE PERIOD BUT THE EML LOOKS TO TAKE OVER WITH
THE CAP STRENGTHENING AND TEMPS WARMING BACK INTO THE LOW/MID 90S.
WE COULD BE LOOKING AT A PATTERN CHANCE BY THE LATTER HALF OF THE
WEEKEND WITH THE DEEP WESTERN TROUGH BEING REPLACED BY A SPLIT
FLOW REGIME.
JOHNSON
&&
.PRELIMINARY POINT TEMPS/POPS...
ABILENE 68 91 69 91 68 / 30 10 5 5 10
SAN ANGELO 68 91 69 92 70 / 30 10 5 5 10
JUNCTION 66 91 69 88 71 / 10 10 5 5 5
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
HUBER
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
1150 PM CDT SAT MAY 25 2013
.AVIATION...
STRONG POST-THUNDERSTORM OUTFLOW WINDS WILL AFFECT THE KLBB
TERMINAL THROUGH ABOUT 0630 UTC. THEN...LOW STRATUS IS EXPECTED TO
DEVELOP AT KCDS BY AROUND 1000 UTC. THERE IS SOME POTENTIAL FOR
MVFR CEILINGS AT KLBB AT WELL...BUT CONFIDENCE IS TOO LOW FOR
MENTION IN THE TAF. ASIDE FROM THE OUTFLOW...SOUTHERLY WINDS ARE
EXPECTED TO PREVAIL. ADDED A CB MENTION AT KLBB BY LATE AFTN TO
ACCOUNT FOR THE EXPECTED DEVELOPMENT OF WIDELY SCATTERED TSRA.
&&
.PREV DISCUSSION... /ISSUED 1024 PM CDT SAT MAY 25 2013/
UPDATE...
ANOTHER QUICK UPDATE TO RECONFIGURE POPS FAVORING THE NORTH-
CENTRAL...SOUTH-CENTRAL AND SOUTHWEST ZONES...GIVEN THE CURRENT
RADAR TRENDS. OVERALL WEAKENING STORM INTENSITIES SHOULD CONTINUE
AS THE BOUNDARY LAYER COOLS...THOUGH GUSTY WINDS...AREAS OF
BLOWING DUST AND BRIEF HEAVY RAINS WILL STILL BE POSSIBLE FOR SOME
TIME AS THE CONVECTIVE COMPLEXES GRADUALLY GUST OUT. NO OTHER
CHANGES MADE TO THE GRIDS ATTM.
PREV DISCUSSION... /ISSUED 652 PM CDT SAT MAY 25 2013/
UPDATE...
QUICK UPDATE TO INCREASE POPS ACROSS THE FAR WESTERN COUNTIES THIS
EVENING...PARTICULARLY THE NORTHWESTERN MOST ZONES...WHERE
STRONG/SEVERE CONVECTION IS POISED TO MOVE IN. HAIL AND WIND
THREAT MAY PERSIST FOR A COUPLE OF HOURS AS STORMS MOVE INTO
STRONG INSTABILITY...THOUGH EXPECT A GRADUALLY WEAKENING TREND
AFTER SUNSET. STILL...GUSTY /AND DUSTY/ OUTFLOW COULD ORGANIZE AND
MAKE A PUSH EASTWARD ACROSS THE CAPROCK. UPDATED PRODUCTS HAVE
BEEN SENT.
PREV DISCUSSION... /ISSUED 631 PM CDT SAT MAY 25 2013/
AVIATION...
AVIATION CONCERNS ARE -TSRA AND/OR STRONG OUTFLOW BOUNDARY AT KLBB
LATE THIS EVENING...AND MVFR CEILINGS AT KCDS EARLY SUNDAY
MORNING. T-STORMS IN EASTERN NM WILL GRADUALLY MOVE EAST THIS
EVENING...BUT WILL LIKELY DECAY BEFORE REACHING KLBB. THE PASSAGE
OF AN OUTFLOW BOUNDARY IS CONSIDERED MORE LIKELY AT THIS
TIME. WE HAVE VERY LOW CONFIDENCE IN WIND SPEEDS ASSOC. WITH ANY
BOUNDARY...SO WE HAVE KEPT THEM ON THE CONSERVATIVE SIDE IN A
TEMPO MENTION. AT KCDS...WE EXPECT LOW STRATUS TO MOVE IN AROUND
10 UTC...THEN GRADUALLY SCOUR OUT SUN MORN. VFR CONDITIONS ARE
EXPECTED AREA-WIDE BY MIDDAY...WITH WIDELY SCATTERED CB DEVELOPING
BY MID TO LATE AFTERNOON.
PREV DISCUSSION... /ISSUED 339 PM CDT SAT MAY 25 2013/
SHORT TERM...
MOIST UPSLOPE FLOW ACROSS EASTERN NEW MEXICO HAS ALREADY SUPPORTED
SCATTERED TSTMS FROM THE SACRAMENTOS NORTH TO SANTA ROSA. A SECOND
AREA OF INTEREST IS EVIDENT ON VIS SATELLITE ALONG THE MESCALERO
ESCARPMENT WHERE AGITATED CU HAVE RECENTLY DEVELOPED. HRRR AND
NAM-WRF BOTH PROG TSTM DEVELOPMENT ALONG THIS CU LINE BEFORE 00Z
AND CARRY IT EASTWARD TO VARIOUS DEGREES WITHIN 20 KNOTS OF
700-500MB FLOW. CONSIDERING CINH IS TRENDING NEGLIGIBLE ALONG THE
NM/TX STATE LINE AND SBCAPE IS AROUND 2K J/KG...HAVE ADDED SEVERE
MENTION TO OUR WESTERNMOST COUNTIES WHERE THIS ACTIVITY WILL LIKELY
PEAK IN INTENSITY BEFORE DIMINISHING THEREAFTER AS THE MIXING LAYER
DECOUPLES. LITTLE/NO BACKGROUND SUPPORT MAY FURTHER LIMIT THE
CHANCES OF THIS PERSISTING OVER THE REMAINDER OF THE SOUTH
PLAINS...BUT WILL KEEP SOME ISOLATED MENTION THROUGH 06Z.
SUNDAY WILL SEE IMPROVED W-SWLY FLOW OVERSPREAD THE REGION RESULTING
IN THE DRYLINE MIXING OUT OF NEW MEXICO AND STALLING SOMEWHERE OVER
THE WESTERN 1/3 OF THE CWA. ALBEIT MODEST...AN ADDITIONAL INFLUX OF
GULF MOISTURE BY EARLY SUNDAY IS PROGGED TO SECURE HIGHER SBCAPES
GENERALLY AROUND 3500 J/KG ALONG THE DRYLINE WITH EVEN EXTREME
VALUES IN THE ROLLING PLAINS...HOWEVER THE LATTER IS SHOWN TO REMAIN
CAPPED AND TOO FAR REMOVED FROM THE DRYLINE. NO DISCERNIBLE SHORT
WAVE TROUGHS ARE PROGGED...BUT AS IS THE CASE TODAY DEEP MIXING
SHOULD PROVE MORE THAN ADEQUATE FOR AT LEAST ISO TSTMS. WINDOW FOR
SUPERCELLS WILL BE OPENED 0-6KM BULK SHEAR VECTORS RISE TO NEARLY 40
KNOTS AND MAINTAIN A PERPENDICULAR ORIENTATION TO THE DRYLINE.
ROBUST CAPE IN THE HAIL GROWTH LAYER COMBINED WITH RELATIVELY HIGH
LCL VALUES WILL OPEN THE WINDOW FOR SOME VERY LARGE HAIL AND DMGG
DOWNBURSTS. MOST HIGH TEMPS WERE KEPT A FEW DEGREES ABOVE
MOS...PARTICULARLY WEST OF THE DRYLINE WHERE OUR HIGHEST ELEVATIONS
COULD END UP WITH THE HOTTEST VALUES FOR THE DAY.
LONG TERM...
HIGH AMPLITUDE RIDGE ORIENTED FROM THE BIG BEND TO THE WESTERN GREAT
LAKES THENCE WELL INTO CENTRAL CANADA WILL CONTINUE ITS SLOW
EASTWARD PROGRESSION AS A COUPLE OF STORM SYSTEMS COME ASHORE THE
PACIFIC NORTHWEST. TOWARD MID WEEK...FLOW ACROSS WEST TEXAS WILL
STRENGTHEN AS NEGATIVELY TILTED TROUGH DEEPENS FROM THE PAC NW.
THURSDAY SHOULD SEE A RETURN TO ZONAL FLOW AS UPPER LOW SETTLES
ACROSS WYOMING THOUGH ANOTHER LOBE OF ENERGY ROTATING AROUND THE WY
SYSTEM WILL APPROACH LATE THU/EARLY FRIDAY WITH SOUTHWESTERLIES
PERSISTING THROUGH DAY 7.
WILL CONTINUE MENTION OF TSRA INTO THE EVENING HOURS ON SUNDAY WITH
CONDITIONS SETTLING AFTER SUNSET. DRYLINE SHOULD PUSH INTO NEW
MEXICO OVERNIGHT THEN TIGHTEN UP AGAIN MONDAY AFTERNOON WITH
CONVECTION LOOKING MOST LIKELY EAST OF A SILVERTON TO BROWNFIELD
LINE THOUGH SOME VARIANCE WILL BE POSSIBLE GIVEN THE INFLUENCES OF
SUNDAY NIGHT/S STORMS. WEDNESDAY LOOKS TO KEEP THE DRYLINE A BIT
FURTHER WEST THUS GIVING MORE OF THE AREA A SHOT AT THE MUCH NEEDED
RAINFALL. WITH THE MORE STRONGLY DIFLUENT FLOW ON WEDNESDAY...THIS
COULD BE THE MOST PRONOUNCED OF THE SEVERE WEATHER THIS WEEK THOUGH
EACH DAY WILL HAVE SEVERE POTENTIAL. THE LONG AND SHORT OF IT IS
THAT EACH DAY OVER THE NEXT WEEK...WE WILL SEE AT LEAST SCATTERED
CONVECTION POTENTIAL EACH AFTERNOON AS THE DRYLINE SLOSHES ACROSS
THE REGION. AT PRESENT...IT WOULD APPEAR THE TORNADO THREAT THIS
WEEK WOULD BE MAXIMIZED ACROSS THE NORTHEASTERN ZONES ON WEDNESDAY.
TO THE WEST OF THE DRYLINE...ELEVATED TO LOW END CRITICAL FIRE
WEATHER CONDITIONS WILL EXIST NEARLY EVERY AFTERNOON AS MIN AFTN RH
DROPS TO THE LOWER TEENS WITH THE BREEZY WEST-OF-THE-DRYLINE WINDS.
OUR NORTHWEST HAS SEEN THE LOWEST AMOUNT OF GREEN-UP DUE TO THE LACK
OF PRECIPITATION THIS SPRING AND WHILE FUELS ARE NOT
PLENTIFUL...WHAT IS THERE WOULD BE EXPECTED TO BURN QUITE EASILY
GIVEN THE RIGHT METEOROLOGICAL CONDITIONS.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 61 94 62 94 61 / 20 20 20 10 10
TULIA 61 94 65 94 64 / 40 20 20 20 20
PLAINVIEW 62 93 65 95 65 / 20 20 20 20 20
LEVELLAND 63 95 68 95 67 / 50 20 20 20 20
LUBBOCK 65 94 67 95 67 / 40 20 20 20 20
DENVER CITY 62 95 68 95 68 / 30 10 10 10 20
BROWNFIELD 63 95 68 96 68 / 60 20 20 20 20
CHILDRESS 68 94 67 94 67 / 20 10 10 10 20
SPUR 65 92 68 95 68 / 20 10 10 10 20
ASPERMONT 68 93 69 92 69 / 10 10 10 10 20
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
33
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1135 PM CDT SAT MAY 25 2013
.AVIATION...
ISOLATED SHOWERS THAT WERE ABOUT 50 MILES SOUTH OF KGKY
/ARLINGTON/ AT 0430Z...WILL CONTINUE TO MOVE NORTH. HAVE PLACED
6SM SHRA IN THE METROPLEX TAFS FOR THE 06-08Z PERIOD...AND MAY
HAVE TO ADD VCTS OR TSRA IF THE SHOWERS BECOME THUNDERSTORMS.
OTHERWISE... EXPECT SOME MVFR STRATUS TO SPREAD NORTH INTO THE
WACO AREA AROUND 09Z...AND INTO THE METROPLEX AROUND 11Z. THE LOW
CLOUDS WILL SCATTER OUT AFTER 16Z SUNDAY. SOUTH WINDS AROUND 10
KNOTS WILL INCREASE TO AROUND 15 KNOTS BY 16Z SUNDAY AND SOME
GUSTS OVER 20 KNOTS ARE LIKELY SUNDAY AFTERNOON. SOME LOW CLOUDS
ARE EXPECTED TO BRING MVFR CIGS UP INTO WACO AND THE METROPLEX
OVERNIGHT SUNDAY NIGHT /07Z AND 09Z MONDAY RESPECTIVELY/.
58
&&
.UPDATE...
00Z FWD RAOB SHOWS THAT WE ARE ALREADY CAPPED AT THE SURFACE FOR
ADDITIONAL CONVECTION. LATEST AREA RADARS SHOW LITTLE ACTIVITY
WHICH IS LIKELY DUE TO THE CAPPING INVERSION. LOWERED THE 50 POPS
ACROSS THE SE TO 30 FOR THE REST OF THE NIGHT. LATEST HIGH-RES
GUIDANCE ALSO KEEPS THINGS RELATIVELY DRY FOR THE NIGHT...WITH
ONLY ISOLATED TO SCATTERED ACTIVITY FORECASTED.
WE DO ALSO HAVE TO WATCH CONVECTION WHICH IS DEVELOPING IN EASTERN
NEW MEXICO AS IT PROGRESSES EAST LATE THIS EVENING AND OVERNIGHT.
LATEST HRRR BRINGS THE WEAKENING STORMS NEAR OUR WESTERN ZONES
AFTER MIDNIGHT BEFORE DYING OFF. WILL KEEP THE 20 POPS ACROSS THE
WEST TO ACCOUNT FOR THIS POTENTIAL.
HAMPSHIRE
&&
.PREV DISCUSSION... /ISSUED 414 PM CDT SAT MAY 25 2013/
THROUGH TONIGHT...LEFT THE EARLY AFTERNOON UPDATE FORECAST
DISCUSSION ATTACHED BELOW FOR REFERENCE AND MORE DETAILS ON THE
SHORT TERM FORECAST CONCERNS.
CHANGES FROM EARLIER DISCUSSION...THE MCV THAT WAS EXPECTED TO
DEVELOP NEAR SAN ANTONIO WAS APPARENT IN REGIONAL RADAR RETURNS
NEAR AUSTIN AND GONZALEZ AT THE TIME OF THIS DISCUSSION. ASSUMING
THAT THIS IS THE PRIMARY MID-LEVEL LOW/MCV PRODUCED BY THE
PERSISTENT SAN ANTONIO AREA CONVECTION THIS MORNING...ADJUSTED
RAIN CHANCES THIS EVENING AND OVERNIGHT IN LINE WITH ITS EXPECTED
TRAJECTORY. THE 19Z RUN OF THE RAP SEEMS TO HAVE A GOOD HANDLE ON
THE POSITION OF THIS MCV...SO GENERALLY USED THIS MODEL FOR
GUIDANCE OVER THE NEXT 12 TO 18 HRS.
THE MCV IS EXPECTED TO MOVE GENERALLY IN A NORTHEASTERLY DIRECTION
THROUGH TONIGHT...TAKING IT FROM ITS CURRENT LOCATION TO JUST
NORTHEAST OF TYLER BY SUNRISE SUNDAY. THE GFS INDICATES THAT THE
UPPER TROUGH THAT WAS ANALYZED IN THE 12Z RAOB ANALYSIS TO THE
WEST OF THE CWA WILL INTERACT WITH THIS MCV FAVORABLY AND RESULT
IN WIDESPREAD THUNDERSTORM ACTIVITY GENERALLY EAST OF I-35 AND
SOUTH OF I-20 AFTER MIDNIGHT...SPREADING NORTHEAST INTO THE
ARKLATEX AREA JUST AFTER SUNRISE. BOTH OF THESE FEATURES
EXIST...SO THIS SOLUTION IS VIABLE...HOWEVER THE FORCING FOR
ASCENT ADVERTISED BY THE GFS IS GREATLY ENHANCED BY CONVECTIVE
FEEDBACK. THAT IS...MODEL GENERATED STORMS COOL OFF LOCATIONS
DOWNSTREAM /NORTHEAST/ ALLOWING WARM AIR ADVECTION TO ARTIFICIALLY
RAMP UP RESULTING IN THE GENERATION OF MORE STORMS. IN SHORT...A
MODEL GENERATED FEEDBACK LOOP. THIS LOOP MAY VERIFY AND RESULT IN
A HEAVY RAINFALL EVENT EAST OF I-35 TO THE ARKLATEX AREA TONIGHT
THROUGH SUNDAY MORNING. HOWEVER THERE IS NOT REALLY ANY HIGH
RESOLUTION MODEL OUTPUT SUPPORT FOR THIS SOLUTION AT THIS
TIME...THEREFORE CONFIDENCE IS SOMEWHAT LOW IN A WIDESPREAD HEAVY
RAIN EVENT.
THAT SAID...MANY FACTORS ARE IN PLACE TO SUPPORT A LOCALIZED HEAVY
RAINFALL EVENT ANYWHERE STORMS EXIST OVER THE NEXT 12 TO 18 HRS.
PRECIPITABLE WATER VALUES ARE ABOVE THE 75TH PERCENTILE OF
HISTORICAL PRECIPITABLE WATER VALUES FOR THIS REGION IN LATE MAY.
MID-LEVEL LAPSE RATES ARE POOR BUT THE ENVIRONMENT IS
UNCAPPED...IN SHORT A FAVORABLE ENVIRONMENT FOR VERY TALL RAIN
SHOWERS WITH LITTLE LIGHTNING ACTIVITY AND ONLY WEAK GENERATION OF
OUTFLOW BOUNDARIES. WEAK OUTFLOW MEANS THAT STORMS CAN REMAIN IN
ONE PLACE FOR A LONGER PERIOD OF TIME INCREASING THE CHANCES FOR
TRAINING OF STORMS AND A LOCALIZED FLOODING THREAT. AT THIS TIME
WENT WITH A MENTION OF LOCALIZED HEAVY RAIN AND FLOODING IN THE
HAZARDOUS WEATHER OUTLOOK AND WORDED FORECAST.
WITH WEAK WIND SHEAR IN THIS THERMODYNAMIC ENVIRONMENT STORMS ARE
EXPECTED TO BEHAVE IN A NEARLY TROPICAL NATURE WITH EFFICIENT
RAINFALL PRODUCTION. THEREFORE CHANCES OF SEVERE WEATHER APPEAR TO
BE VERY SMALL TONIGHT. WE WILL HAVE TO KEEP A CLOSE EYE ON THE
EVOLUTION OF A LOCALIZED FLOODING EVENT...ESPECIALLY WITH MANY
PEOPLE LIKELY CAMPING OUTDOORS IN FLOOD PRONE AREAS THROUGH
TONIGHT.
SUNDAY...SUNDAY MORNING WE WILL LIKELY HAVE SOME REMNANT POCKETS
OF HEAVY RAIN ALONG A SULPHUR SPRINGS TO PALESTINE LINE...LIKELY
MOVING NORTHEAST TOWARDS THE ARKLATEX REGION THROUGHOUT THE
MORNING HOURS. FROM THE WEST...THE HRRR HAS CONSISTENTLY INDICATED
THAT A SQUALL LINE WILL ORGANIZE OVER THE SOUTHERN HIGH PLAINS/TX
PANHANDLE TONIGHT AND MOVE EAST TOWARDS OUR WESTERN CWA EARLY
SUNDAY MORNING. WE WILL HAVE TO KEEP AN EYE ON THIS...NOT SO MUCH
FROM A SEVERE WEATHER STAND POINT BUT FROM ANOTHER POTENTIAL
SOURCE FOR MCV PRODUCTION. WITH THE SAN ANTONIO AREA MCV AND
LARGER UPPER TROUGH MOVING EAST...SUBSIDENCE WILL LIKELY DOMINATE
ANY MCV MOVING OFF THE HIGH PLAINS AND THRU NORTH TX TOMORROW.
HOWEVER UNTIL WE GET SOME DRIER AIR IN OVER THE REGION CAPPING OFF
THE ATMOSPHERE FOR THUNDERSTORM DEVELOPMENT...WILL HOLD ON TO A
BROAD BRUSHED MENTION OF SHOWERS AND THUNDERSTORMS IN THE FORECAST
ACROSS ALL OF NORTH TX THROUGH SUNDAY.
NEXT WEEK...BEGINNING MONDAY A WESTERN CONUS TROUGH IS EXPECTED TO
ORGANIZE SENDING THE WEAK UPPER LEVEL RIDGE AND ENTRAPPED MCV
FEATURES OFF TO THE EAST OF THE REGION. THIS IS EXPECTED TO RESULT
IN SOUTHWEST FLOW ALOFT OVER NORTH TX ON MONDAY WHICH SHOULD HELP
TO ADVECT A RELATIVELY STOUT CAP IN PLACE OVER THE REGION BY
MONDAY AFTERNOON. THIS CAP IS EXPECTED TO HOLD IN PLACE THROUGH
THE WEEK UNLESS THE DRYLINE OR A STRONG SHORTWAVE TROUGH CAN LIFT
THE CAP AND RESULT IN THUNDERSTORM INITIATION DURING THE WEEK
AHEAD.
WE ARE EXPECTED TO HAVE RELATIVELY PERSISTENT...BREEZY SOUTH
WINDS IN PLACE BELOW THE CAP THROUGH THE WEEK. THIS WILL HELP KEEP
GOOD GULF MOISTURE IN PLACE UNDER THE CAP PROVIDING PLENTY OF
POSITIVE CAPE FOR THUNDERSTORM DEVELOPMENT IF ANYTHING CAN REMOVE
THE CAP. WITHOUT STORMS...WE WILL LIKELY SEE HIGHS HOLD IN THE
UPPER 80S WITH LOWS IN THE LOWER TO MID 70S EACH DAY. THE GFS AND
ECMWF BOTH INDICATE THAT A STRONG SHORTWAVE TROUGH WILL MOVE OVER
THE SOUTH PLAINS WEDNESDAY THROUGH WEDNESDAY EVENING. THE ECMWF
REMAINS FURTHER SOUTH WITH THIS TROUGH WHICH IS WHAT WE WILL NEED
TO LIFT THE CAP AND RESULT IN STORMS ACROSS THE CWA WEDNESDAY
AFTERNOON AND EVENING. THE GFS INDICATES THE BEST FORCING STAYS
NORTH OF THE CWA. WENT AHEAD WITH 20 TO 30 POPS WEST OF INTERSTATE
35...CLOSEST TO THE UPPER TROUGH WEDNESDAY AFTERNOON THROUGH
WEDNESDAY NIGHT AS RESULT. REMOVED POPS THEREAFTER WITH ALL
GUIDANCE INDICATING SUBSIDENCE BEHIND THIS UPPER TROUGH ON
THURSDAY.
CAVANAUGH
&&
.PRELIMINARY POINT TEMPS/POPS...
DALLAS-FT. WORTH, TX 69 84 67 86 69 / 30 20 10 0 0
WACO, TX 68 86 67 88 69 / 30 20 10 0 0
PARIS, TX 69 82 65 84 67 / 30 30 10 0 0
DENTON, TX 66 83 66 85 68 / 30 20 10 0 0
MCKINNEY, TX 68 82 66 86 68 / 30 20 10 0 0
DALLAS, TX 71 83 70 88 72 / 30 20 10 0 0
TERRELL, TX 70 82 67 87 69 / 30 30 10 0 0
CORSICANA, TX 69 83 68 88 69 / 30 20 10 0 0
TEMPLE, TX 68 85 67 87 69 / 30 20 10 0 0
MINERAL WELLS, TX 67 86 66 87 68 / 20 20 10 0 5
&&
.FWD WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
58/85
AREA FORECAST DISCUSSION...UPDATED
NWS SAN ANGELO TX
1120 PM CDT SAT MAY 25 2013
.UPDATE...
FORECAST HAS BEEN UPDATED FOR POPS...WEATHER AND SKY CONDITION
OVERNIGHT. SEE DISCUSSION.
&&
.DISCUSSION...
HAVE BEEN MONITORING THE PROGRESS OF A MESOSCALE CONVECTIVE
SYSTEM MOVING EAST-SOUTHEAST ACROSS WEST TEXAS. ALTHOUGH TOPS
ARE WARMING ON INFRARED SATELLITE IMAGERY...THE SYSTEM IS STILL
HOLDING STRONG AND APPROACHING OUR WESTERN BORDER COUNTIES.
MOVEMENT OF CONVECTION ALONG THE LEADING EDGE IS SOUTHEAST NEAR
40 KT. EXPECT THIS MCS TO EVENTUALLY DISSIPATE OVERNIGHT WHILE
MOVING SOUTHEAST ACROSS OUR AREA. BASED ON RADAR AND SATELLITE
TRENDS...HAVE UPDATED THE FORECAST PRODUCTS FOR WEATHER/POPS AND
SKY CONDITION. CARRYING THE HIGHEST POPS ALONG OUR WESTERN
COUNTIES...TRAILING OFF TO BELOW 15 PERCENT ACROSS OUR FAR EASTERN
AND SOUTHEASTERN COUNTIES. ADDITIONAL UPDATES WILL BE ISSUED AS
NEEDED OVERNIGHT.
&&
.PREV DISCUSSION... /ISSUED 630 PM CDT SAT MAY 25 2013/
DISCUSSION...
EXPECT STRATUS TO BRING MVFR CEILINGS BACK TO WEST CENTRAL TEXAS
DURING THE NEXT 6 HOURS. AVIATION BELOW HAS DETAILS.
AVIATION...
MODELS DATA INDICATE STRATUS WILL RETURN TO WEST CENTRAL TEXAS
TONIGHT AND PERSIST UNTIL AROUND NOON TOMORROW. THE LATEST RUC 925
MB RELATIVE HUMIDITY AND WIND FIELD DATA INDICATE STRATUS WILL
RETURN TO WEST CENTRAL TEXAS...FROM THE EAST AND
SOUTHEAST...BEGINNING AROUND 03Z. BY 06Z TONIGHT...PLAN FOR MVFR
CEILINGS TO DOMINATE WEST CENTRAL TEXAS. MOS GUIDANCE DATA FROM
THE GFS INDICATE MVFR CEILINGS AROUND 1500 FEET ABOVE GROUND LEVEL
AT ALL 5 TERMINALS. THE NAM BASED GUIDANCE IS MORE AGGRESSIVE AND
PREDICTS IFR CEILINGS AROUND 700 FEET ABOVE GROUND LEVEL. I
DECIDED TO CONTINUE WITH A FORECAST FAVORING THE GFS
SOLUTION...MAINLY BASED ON PERSISTENCE. AS WAS THE CASE
TODAY...LOOK FOR VFR CEILINGS TO RETURN TO WEST CENTRAL TEXAS
AROUND NOON TOMORROW.
HUBER
PREV DISCUSSION... /ISSUED 501 PM CDT SAT MAY 25 2013/
UPDATE...
FORECAST IS BEING UPDATED FOR POPS...QPF AND SKY CONDITION. SEE
DISCUSSION.
DISCUSSION...
SCATTERED SHOWERS WHICH WERE OVER THE EASTERN THIRD OF WEST CENTRAL
TEXAS EARLIER TODAY HAVE SINCE MOVED OUT OF THE AREA OR DISSIPATED.
RADAR LATE THIS AFTERNOON SHOWS NO ADDITIONAL SHOWER OR THUNDERSTORM
DEVELOPMENT...BUT A SLIGHT CHANCE REMAINS GIVEN THE MOIST AND
UNSTABLE AIRMASS STILL IN PLACE. WITH THE UPPER TROUGH AXIS MOVING
FARTHER AWAY FROM OUR AREA AND ACROSS EAST TEXAS...AND WITH THE
CONVECTIVE ACTIVITY DIURNALLY DRIVEN...EXPECT THE RAIN CHANCE IN
WEST CENTRAL TEXAS TO END BY OR BEFORE 9 PM. HAVE ADJUSTED THE
21Z-00Z WEATHER GRID TO REFLECT THE AFOREMENTIONED TRENDS...AND HAVE
ENDED THE RAIN CHANCE AFTER 02Z. THE GFS AND NAM BOTH SUGGEST LOW
CLOUD DEVELOPMENT NORTHWEST INTO OUR AREA LATE TONIGHT AND EARLY
SUNDAY MORNING...IN MOIST SOUTHEASTERLY BOUNDARY LAYER FLOW. HAVE
ADJUSTED THE SKY CONDITION GRIDS TO REFLECT THIS SCENARIO WITH
INCREASING CLOUDINESS TOWARD MORNING...TO ROUGHLY THE INTERSTATE 20
CORRIDOR. EXPECT THE LOW CLOUD FIELD TO ERODE BY MID TO LATE SUNDAY
MORNING. HAVE ALSO MADE DOWNWARD ADJUSTMENTS TO THE QPF GRIDS FROM
21Z-00Z. WITH LOW CONFIDENCE IN MEASURABLE PRECIPITATION OCCURRING
TONIGHT...HAVE DROPPED THE QPF GRIDS TO ZERO. UPDATED FORECAST
PRODUCTS WILL BE OUT SHORTLY.
PREV DISCUSSION... /ISSUED 341 PM CDT SAT MAY 25 2013/
SHORT TERM...
EARLY THIS AFTERNOON...UPPER TROUGH AXIS IS LOCATED JUST EAST OF
THE FORECAST AREA WITH ASSOCIATED RAINFALL AND THUNDERSTORMS
OCCURRING FROM THE CENTRAL TEXAS GULF COAST NORTH OVER MUCH OF
EAST TEXAS. WITH THE CLOSE PROXIMITY OF THE UPPER LOW TO OUR
CWA...WILL MAINTAIN A SLIGHT CHANCE OF SHOWERS AND ISOLATED
THUNDERSTORMS THROUGH THE NIGHT. AS THE UPPER TROUGH CONTINUES TO
MOVE EAST DURING THE DAY TOMORROW...AN UPPER RIDGE WILL BUILD OVER
THE OUR AREA FROM THE WEST...BRINGING AN END TO OUR RAINFALL
CHANCES. AFTER SUNDAY MORNING LOWS GENERALLY IN THE MID 60S...
AFTERNOON HIGHS ON SUNDAY WILL BE WARMER THAN TODAY...LOWER 90S VS
LOW TO MID 80S.
15
LONG TERM...
THE LONG TERM PORTION OF THE FORECAST WILL BE HIGHLIGHTED BY
PERSISTENT STRONG SOUTHERLY FLOW...OVERNIGHT AND MORNING
STRATUS...AND MIDWEEK PRECIPITATION CHANCES.
THE WEST COAST TROUGH IS PROGGED TO DEEPEN EARLY NEXT WEEK AS THE
SHORTWAVE TROUGH CURRENTLY LOCATED SOUTH OF THE ALEUTIANS MOVES
INTO THE PACNW. WE WILL SEE INCREASING SOUTHWEST FLOW ALOFT WHICH
WILL BOTH ENHANCE THE ELEVATED MIX LAYER /EML/ AND SUPPORT LEE
CYCLOGENESIS. THE LATTER WILL PROVIDE BRISK SOUTH WINDS THROUGHOUT
THE DURATION OF THE FORECAST PERIOD...WITH DAYTIME WIND SPEEDS OF
15-25 MPH AREAWIDE. A STRONG NOCTURNAL LOW LEVEL JET WILL KEEP
GUSTS IN THE FORECAST DURING THE OVERNIGHT HOURS WITH THE
STRONGEST WINDS FOUND ACROSS THE CONCHO VALLEY AND BIG COUNTRY.
THESE SOUTH WINDS WILL PROVIDE A STEADY STREAM OF GULF MOISTURE
INTO THE AREA...KEEPING DEWPOINTS GENERALLY IN THE LOWER 60S AND
PUSHING OVERNIGHT LOWS INTO THE UPPER 60S AND LOWER 70S THROUGH
THE WEEK. THESE BREEZY CONDITIONS MAY BE TEMPORARILY INTERRUPTED
BY CONVECTIVE OUTFLOW BUT I WILL GET MORE INTO THAT IN A BIT.
I EXPECT DRY CONDITIONS THROUGH MONDAY...ALTHOUGH SOME DIURNAL
CONVECTION TO OUR WEST MAY TRY TO SNEAK INTO THE WESTERN ZONES
MONDAY EVENING. THAT SAID...THE STEERING FLOW WILL KEEP THE BEST
CHANCES TO OUR NORTH AND WEST. OTHERWISE...THE CAP LOOKS TO HOLD
AND KEEP A LID ON THE CONVECTIVE POTENTIAL. TEMPS ON MONDAY ARE
EXPECTED TO RANGE FROM THE UPPER 80S TO LOWER 90S ACROSS MOST OF
WEST CENTRAL TX.
PRECIPITATION STILL DO NOT LOOK ALL THAT PROMISING ON TUESDAY DUE
TO THE STRENGTH OF THE EML. THAT SAID...I DID INCLUDE A SLIGHT
CHANCE OF THUNDERSTORMS GENERALLY WEST OF A SONORA...TO WINTERS...
TO HASKELL LINE TO ACCOUNT FOR THE EASTWARD DRIFT ON CONVECTION
OVER WEST TX. THE BEST RAIN CHANCES APPEAR TO OCCUR ON WEDNESDAY.
THE MEDIUM RANGE GUIDANCE IS DEPICTING A NEGATIVELY TILTED
SHORTWAVE TROUGH EJECTING INTO THE SOUTHERN PLAINS BY WEDNESDAY
AFTERNOON. THEY DO DIFFER IN THE LOCATION OF THE STRONGEST
FORCING...WITH THE GFS FAVORING THE CENTRAL HIGH PLAINS AND THE
ECMWF LOOKING FARTHER SOUTH TOWARD WEST TX. EITHER WAY...SYNOPTIC
SCALE FORCING WILL WORK ON THE EML...LIFTING AND COOLING THE LAYER
TO ERODE THE CAP. THE BIGGEST QUESTION IS HOW FAR SOUTH THIS
ASCENT REACHES. THE SEVERE POTENTIAL WILL EXIST GIVEN THE STEEP
MID LEVEL LAPSE RATES...STRONG INSTABILITY AND MORE THAN ADEQUATE
DEEP LAYER SHEAR. THE BIG QUESTION /AS IS USUALLY THE CASE/ IS THE
CAP.
THUNDERSTORM CHANCES LINGER ON THURSDAY BUT THE STRONGEST FORCING
LOOKS TO MOVE EAST BY THURSDAY. MODEL CONSENSUS SHOWS A DEEP...
BROAD TROUGH OVER THE WESTERN 2/3 OF THE CONUS WITH STRONG WEST
SOUTHWEST FLOW OVER WEST TX. WE MAY BEGIN TO SEE THE DRYLINE DRY
TO MIX EAST LATE IN THE PERIOD BUT THE EML LOOKS TO TAKE OVER WITH
THE CAP STRENGTHENING AND TEMPS WARMING BACK INTO THE LOW/MID 90S.
WE COULD BE LOOKING AT A PATTERN CHANCE BY THE LATTER HALF OF THE
WEEKEND WITH THE DEEP WESTERN TROUGH BEING REPLACED BY A SPLIT
FLOW REGIME.
JOHNSON
&&
.PRELIMINARY POINT TEMPS/POPS...
ABILENE 68 91 69 91 68 / 30 10 5 5 10
SAN ANGELO 68 91 69 92 70 / 30 10 5 5 10
JUNCTION 66 91 69 88 71 / 10 10 5 5 5
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
99/99
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
230 AM CDT SUN MAY 26 2013
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 230 AM CDT SUN MAY 26 2013
CONVECTION HAS LIT UP DURING THE OVERNIGHT HOURS IN RESPONSE TO THE
SURFACE/850 MB WARM FRONT AND THE IMPINGEMENT OF THE LOW LEVEL
JET/MOISTURE TRANSPORT. HRRR DOING A DECENT JOB WITH THE CURRENT
CONVECTION...AND WILL NUDGE THIS TO LOCATIONS WEST OF THE
MISSISSIPPI RIVER BETWEEN 12-15Z. THIS MATCHES UP WITH THE SPCWRF.
ARWWRF/NAM12 MEANWHILE DECREASE THE AREAL COVERAGE AS IT MOVES EAST
THIS MORNING...BUT STILL HANG ON TO ISOLD/SCT SHOWERS INTO THE
AFTERNOON.
EXPECTATION IS FOR ANOTHER THUNDERSTORM COMPLEX TO DEVELOP OVER THE
CENTRAL PLAINS/WESTERN IA LATER TONIGHT...WITH AN EAST/NORTHEAST
PUSH INTO THE FORECAST AREA.
.LONG TERM...(MONDAY THROUGH SUNDAY)
ISSUED AT 230 AM CDT SUN MAY 26 2013
PRIMARY WEATHER MAKERS FOR THE NEXT FEW DAYS REMAIN UNCHANGED...A
WARM FRONT...POSITION/STRENGTH OF THE LOW LEVEL JET/MOISTURE
TRANSPORT...AND CONVECTION INDUCED MCVS/ENHANCED SHORTWAVE TROUGHS.
WHERE THESE LIE...MOVE...AND MOST IMPORTANTLY...INTERACT...WILL BE
WHERE THE GREATEST THREAT FOR SHOWERS AND THUNDERSTORMS WILL BE.
NAM/GFS/ECMWF HAVE BEEN IN PRETTY GOOD AGREEMENT WITH ADVANCING THE
WARM FRONT...CURRENTLY LYING WEST-EAST ACROSS NORTHERN MO/SOUTHERN
ILL...NORTHWARD ON MONDAY...ENDING UP ACROSS NORTHERN WI LATE WED
NIGHT. THE 850 MB MOISTURE TRANSPORT NOSES INTO/ACROSS THE FRONT ON
MONDAY...BULLSEYEING THE FORECAST AREA. A 500 MB MCV/SHORTWAVE
TROUGH WILL SPIN ACROSS THE PLAINS AND OVER THE UPPER MISSISSIPPI BY
00Z TUES...AIDING SHOWER/STORM DEVELOPMENT.
TUE PROVIDES A SIMILAR SCENARIO WITH A SHORTWAVE TROUGH MOVING IN
FROM THE WEST...BEING ENHANCED FROM CONVECTION SPAWNED FROM THE
MOISTURE TRANSPORT/WARM FRONT INTERACTIONS OVER IA/SOUTHERN MN. THE
FIRST PART OF TUES LOOKS WET AS THE CONVECTIVE COMPLEX FROM LATE
MONDAY MOVES THROUGH. THE LATER 1/2 SHOULD SEE A BREAK FROM
WIDESPREAD RAIN...WITH YET ANOTHER COMPLEX THEN MOVING IN OVERNIGHT
AS CONVECTION SPARKS TO THE WEST.
WED HAS THE WARM FRONT MOVING NORTH OF THE FORECAST AREA...BUT HOW
QUICKLY THIS OCCURS WILL DEPEND ON WHERE THAT EXPECTED RAIN AREA
IS...AND HOW SOON IT EXITS. THIS WOULD SHIFT THE MAIN PCPN FOCUS
TO THE NORTH - ALTHOUGH ONLY BRIEFLY. A SHORT DRYING PERIOD COULD
SEE THE THREAT FOR SHOWERS/STORMS RETURN BY THU
AFTERNOON...CONTINUING INTO FRIDAY. A STRONG PUSH OF LOW LEVEL
MOISTURE WILL REMAIN THE MAIN FIRING MECHANISM...WITH SOME HELP FROM
ENERGY MOVING OUT OF THE UPPER LEVEL TROUGH SITTING TO THE WEST.
DIFFERENCES CONTINUE TO CROP UP BETWEEN THE GFS/EC IN HOW THEY WANT
TO HANDLE THE EVENTUALLY BREAK DOWN/EXIT OF THE TROUGH TO THE WEST
IN THIS RATHER STAGNANT PATTERN. THE GFS REMAINS THE MORE
PROGRESSIVE OF THE SOLUTIONS...WHILE THE EC CONTINUES TO SUGGEST A
CLOSED LOW WOULD DEVELOP...AND SLOW DOWN ITS ALREADY LETHARGIC
STROLL EAST. OBVIOUS IMPLICATIONS IN RAIN CHANCES FOR THE WEEKEND.
WITH CONFIDENCE NOT HIGH IN EITHER OUTCOME...WILL STAY THE COURSE
WITH THE CONSENSUS SOLUTION FOR THE DETAILS.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT
1127 PM CDT SAT MAY 25 2013
THE MAIN FOCUS THROUGH SUNDAY NIGHT IS WITH RAIN CHANCES AND
WHETHER ANY MVFR/IFR CONDITIONS WILL DEVELOP AS A WARM FRONT
PUSHES SLIGHTLY NORTHEAST. SHOWERS AND THUNDERSTORMS HAVE
DEVELOPED FROM SIOUX FALLS SOUTH DAKOTA DOWN TOWARD DES MOINES
IOWA AND ARE EXPECTED TO BE THE MAIN FOCUS FOR THE POSSIBILITY OF
RAIN BY SUNDAY MORNING AT RST. WITH THE MAIN INSTABILITY AXIS
REMAINING TO THE SOUTHWEST...DO NOT ANTICIPATE ANY THUNDERSTORMS
MAKING IT THIS FAR EAST WITH RST MORE LIKELY TO SEE THE RAIN THAN
LSE. AS THE FRONT DRIFTS SLIGHTLY TO THE NORTHEAST THIS MORNING
AND AFTERNOON...SOME OF THE MVFR TO IFR CEILINGS MAY LIFT TO THE
NORTHEAST AS WELL AND SHOULD AT LEAST MAKE IT TO THE DOORSTEP OF
RST. ANOTHER ROUND OF RAIN COULD MOVE IN LATE SUNDAY...BUT
CONFIDENCE IN THIS OCCURRING IT NOT HIGH ENOUGH AT THIS POINT TO
PUT IT INTO THE TAFS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...RIECK
LONG TERM....RIECK
AVIATION.....HALBACH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1127 PM CDT SAT MAY 25 2013
.SHORT TERM...(THIS EVENING THROUGH SUNDAY)
ISSUED AT 341 PM CDT SAT MAY 25 2013
AT 3 PM...A DYING MESOSCALE CONVECTIVE COMPLEX WAS LOCATED OVER
CENTRAL ILLINOIS. THIS SYSTEM PRODUCED UP TO 4 INCHES OF RAIN
ACROSS PARTS OF STORY...MARSHALL...AND JASPER COUNTIES IN CENTRAL
IOWA. MEANWHILE NORTHEAST IOWA AND MOWER COUNTY IN SOUTHEAST
MINNESOTA...RECEIVED UP TO A THIRD OF AN INCH /KARX RADAR WAS
OVERESTIMATING BY UP TO 300 PERCENT IN SOME LOCATIONS/. THE RAIN
AND CLOUDS FROM THIS SYSTEM KEPT TEMPERATURES IN THE LOWER AND MID
50S IN THESE AREAS WHICH IS VERY CLOSE TO THE RECORD COLDEST
MAXIMUM TEMPERATURES FOR THE DATE. THE RECORD COLD MAXIMUM FOR THE
DATE IS 46 IN 1992 FOR AUSTIN MN...48 IN 1943 IN CHARLES CITY
IA...AND 53 IN 1992 IN DECORAH IA. THE DECORAH RECORD IS THE ONLY
ONE THAT COULD POSSIBLY BE BROKEN OR TIED. MEANWHILE AREAS NORTH
OF INTERSTATE 94 SAW A BIT OF SUNSHINE AND THEY WERE ABLE TO WARM
INTO THE MID 60S.
FOR TONIGHT AND SUNDAY...THE MAIN CONCERN IS THE TRACK OF THE
MESOSCALE CONVECTIVE COMPLEX OVER WESTERN NORTH DAKOTA. CORFIDI
VECTORS SUGGEST THAT THIS SYSTEM WILL MOVE EAST ACROSS THE DAKOTAS
THIS EVENING...AND THEN IT WILL MOVE SOUTHEAST ACROSS THE EASTERN
THIRD OF SOUTH DAKOTA...SOUTHERN AND WESTERN MINNESOTA AND NORTHERN
IOWA TONIGHT. OVERALL...THE 25.18Z HRRR HAS THE BEST HANDLE ON THIS
SYSTEM AND IT HAS THIS SYSTEM OVER SOUTHWEST MINNESOTA BY 26.06Z.
WITH THAT SPEED...IT SHOULD MOVE INTO NORTHEAST IOWA AND PARTS OF
SOUTHEAST MINNESOTA BY 26.10Z...AND THEN LINGER ACROSS THESE AREAS
THROUGH MUCH OF SUNDAY MORNING. AHEAD OF THIS SYSTEM...THE
RAP...GFS...NAM/WRF...AND ECMWF SHOW THAT SCATTERED SHOWERS AND
THUNDERSTORMS WILL DEVELOP NORTH OF A WARM FRONT FROM NORTHWEST
IOWA TO SOUTHEAST IOWA. THIS PRECIPITATION IS ASSOCIATED WITH
MODERATE 925 TO 850 MB MOISTURE TRANSPORT AND 310K ISENTROPIC
LIFT.
LIKE TODAY...EXPECT THE LOW CLOUDS AND PRECIPITATION TO KEEP
TEMPERATURES IN THE MID AND UPPER 50S ACROSS SOUTHEAST
MINNESOTA...NORTHEAST IOWA...AND SOUTHWEST WISCONSIN ON SUNDAY.
MEANWHILE SOME SUN NORTH OF INTERSTATE 94 WILL ALLOW TEMPERATURES
TO WARM INTO THE MID 60S.
.LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY)
ISSUED AT 341 PM CDT SAT MAY 25 2013
ON SUNDAY NIGHT AND MONDAY...THE WARM FRONT WILL MOVE INTO NORTH
SOUTHWEST IOWA. WEAK TO MODERATE 925 AND 850 MB MOISTURE TRANSPORT
WILL RESULT IN THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS NORTH
OF THE WARM FRONT FROM NORTH CENTRAL IOWA SOUTHEAST INTO SOUTHEAST
IOWA. THE GFS...ECMWF...AND GEM SUGGEST THAT A MESOSCALE
CONVECTIVE COMPLEX WILL DEVELOP ACROSS EASTERN SOUTH DAKOTA LATE
SUNDAY NIGHT...AND THE DYING SYSTEM MOVES EAST THROUGH OUR AREA
MONDAY.
FROM MONDAY NIGHT INTO TUESDAY...THE MODELS ARE CONTINUING TO
STRUGGLE WITH THE LOCATION OF THE WARM FRONT. THE NAM/WRF STALLS
THE WARM FRONT NEAR THE MINNESOTA AND IOWA BORDER. THIS MAKES A
LOT OF SENSE IF A LOT OF CONVECTION DEVELOPS NORTH OF THIS FRONT
AND ITS COLD POOL PREVENTS THIS WARM FRONT MOVING ANY FURTHER
NORTH. MEANWHILE THE GFS AND ECMWF WOULD SYNOPTICALLY FAVOR THAT
THE WARM FRONT WOULD MOVE NORTHWARD THROUGH THE AREA. HOWEVER THE
CAP IN THE WARM SECTOR REMAINS SOUTHWEST OF THE FORECAST
AREA...THUS THERE WOULD BE THE POTENTIAL FOR A SERIES OF MESOSCALE
CONVECTIVE SYSTEMS TO MOVE THROUGH THE AREA. SO IN EITHER
SCENARIO...IT LOOKS LIKE THE FORECAST AREA WILL REMAIN WET. WITH
PRECIPITABLE WATER VALUES AROUND 1.5 INCHES AND WARM CLOUD LAYER
DEPTHS UP TO 4KM...THERE WILL BE THE POTENTIAL FOR HEAVY RAIN FROM
ANY SHOWERS AND THUNDERSTORMS THAT DEVELOP. IN ADDITION...WILL
HAVE TO WATCH FOR THE POTENTIAL OF SEVERE WEATHER...BUT THIS IS
HIGHLY DEPENDENT UPON THE LOCATION OF THE WARM FRONT.
FROM TUESDAY NIGHT INTO SATURDAY...IT CONTINUES TO LOOK LIKE A
SERIES OF SHORT WAVE TROUGHS WILL MOVE THROUGH THE REGION. HOWEVER
THE TIMING OF THESE WAVES IS UNCERTAIN...THUS KEPT PRECIPITATION
CHANCES IN THE 40 TO 60 PERCENT RANGE THROUGH THIS TIME PERIOD.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1127 PM CDT SAT MAY 25 2013
THE MAIN FOCUS THROUGH SUNDAY NIGHT IS WITH RAIN CHANCES AND
WHETHER ANY MVFR/IFR CONDITIONS WILL DEVELOP AS A WARM FRONT
PUSHES SLIGHTLY NORTHEAST. SHOWERS AND THUNDERSTORMS HAVE
DEVELOPED FROM SIOUX FALLS SOUTH DAKOTA DOWN TOWARD DES MOINES
IOWA AND ARE EXPECTED TO BE THE MAIN FOCUS FOR THE POSSIBILITY OF
RAIN BY SUNDAY MORNING AT RST. WITH THE MAIN INSTABILITY AXIS
REMAINING TO THE SOUTHWEST...DO NOT ANTICIPATE ANY THUNDERSTORMS
MAKING IT THIS FAR EAST WITH RST MORE LIKELY TO SEE THE RAIN THAN
LSE. AS THE FRONT DRIFTS SLIGHTLY TO THE NORTHEAST THIS MORNING
AND AFTERNOON...SOME OF THE MVFR TO IFR CEILINGS MAY LIFT TO THE
NORTHEAST AS WELL AND SHOULD AT LEAST MAKE IT TO THE DOORSTEP OF
RST. ANOTHER ROUND OF RAIN COULD MOVE IN LATE SUNDAY...BUT
CONFIDENCE IN THIS OCCURRING IT NOT HIGH ENOUGH AT THIS POINT TO
PUT IT INTO THE TAFS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...HALBACH
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1049 PM MDT SAT MAY 25 2013
.UPDATE...
ISSUED AT 617 PM MDT SAT MAY 25 2013
SHOWERS AND THUNDERSTORMS HAVE NOT BEEN VERY NUMEROUS OVER THE
CWA LATE THIS AFTERNOON AND EARLY THIS EVENING. POTENTIAL STILL
EXISTS OVER THE PANHANDLE THIS EVENING FOR STRONG OR EVEN SEVERE
STORMS...ESPECIALLY THE NORTHERN PORTION. THAT AREA IS AHEAD OF
A SURFACE BOUNDARY CURRENTLY ALONG THE EASTERN WYOMING BORDER.
AHEAD OF THE BOUNDARY STILL EXISTS MOIST AND UNSTABLE AIR WITH
CAPE VALUES BETWEEN 1000 AND 2000 J/KG/. MINIMAL THUNDERSTORM
COVERAGE EARLY THIS EVENING MAY BE DUE TO THE PERSISTENT CIRRUS.
ALSO...THE LOW LEVEL THETA RIDGE AXIS BEING EAST OF THE CWA...
EXCEPT FOR THE FAR NORTHERN PANHANDLE. IN A RECENT UPDATE MADE
SOME ADJUSTMENTS TO THE POPS AND CLOUDS. WILL TAKE A LOOK SOON AT
THE POSSIBILITY OF LOW CLOUDS AND FOG REDEVELOPING OVER PARTS OF
THE PANHANDLE LATER TONIGHT.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 230 PM MDT SAT MAY 25 2013
VISIBLE SATELLITE LOOP SHOWS PARTLY CLOUDY SKIES WITH CONVECTION
JUST STARTING TO INITIATE NEAR THE NEBRASKA BORDER THIS AFTERNOON.
RELATIVELY QUIET RIGHT NOW WITH ONLY SOME VIRGA SHOWING UP ON
RADAR. SURFACE BOUNDARY/DRYLINE FEATURE JUST WENT THROUGH KIMBALL
NEBRASKA INDICATIVE OF THE SURFACE DEWPOINT DROP BY 7C IN ONLY A
HALF AN HOUR AND WINDS SHIFTED INTO THE SOUTHWEST. THIS BOUNDARY
IS LOCATED NEAR KIMBALL AND EXTENDS NORTHWEST TO NEAR GUERNSEY
WYOMING...AND FURTHER NORTH TO AROUND THE DOUGLAS AREA. THIS
BOUNDARY WILL CONTINUE TO MOVE SLOWLY EAST THIS AFTERNOON.
DEWPOINTS AHEAD OF THIS BOUNDARY ARE IN THE 50S TO NEAR 60 INTO
WESTERN NEBRASKA WITH DEWPOINTS IN THE TEENS AND 20S WEST OF THE
BOUNDARY. PRETTY GOOD CONVERGENCE ALONG THIS BOUNDARY...AND WITH
AMPLE MOISTURE AHEAD OF IT...THERE IS CONCERN FOR SEVERE
THUNDERSTORMS EAST OF A LINE FROM LUSK WYOMING TO SIDNEY NEBRASKA.
MODEL SOUNDINGS CONTINUE TO INDICATE LOW LI/S DOWN TO AROUND -7C
AND CAPE VALUES AROUND 2000 TO 2500 J/KG IN THESE AREAS WITH 30 TO
50 KNOTS OF SHEAR...ESPECIALLY OVER THE NORTHERN NEBRASKA
PANHANDLE. WILL CONTINUE TO MONITOR AND EVALUATE THE
ENVIRONMENT...WITH THE POTENTIAL OF A SEVERE TSTORM OR TORNADO
WATCH AFTER 3 PM THIS AFTERNOON.
FOR TONIGHT...THE SHORTWAVE RESPONSIBLE FOR THE STRONGER TSTORMS
WILL QUICKLY PUSH EAST OF THE FORECAST AREA LATE THIS EVENING.
THINK THE POTENTIAL FOR FOG IS A BIT LESS TONIGHT...BUT ADDED
PATCHY FOG TO LOCATIONS WHICH ARE MORE LIKELY TO SEE SOME RAINFALL
THIS EVENING. OTHERWISE...TEMPERATURES WILL REMAIN MILD TONIGHT.
FOR SUNDAY AND MONDAY...POTENTIAL FOR TSTORMS WILL SHIFT A BIT
FURTHER WEST DURING THE DAY AS ANOTHER SHORTWAVE TROUGH PUSHES
ACROSS SOUTHEAST WYOMING LATE IN THE DAY. HOWEVER...ANY SEVERE
WEATHER THREAT SHOULD SHIFT A LITTLE FURTHER NORTHEAST OVER
CENTRAL NEBRASKA AND SOUTHERN SOUTH DAKOTA. SIMILAR CONDITIONS ARE
EXPECTED ON MONDAY AS ANOTHER SHORTWAVE ALOFT TAKES A VERY SIMILAR
TRACK COMPARED TO SUNDAY...BUT THE SEVERE WEATHER THREAT WILL BE
EVEN LESS WITH DRIER NORTHWEST WINDS. TEMPERATURES WILL REMAIN
ABOVE NORMAL...BUT WILL LOWER A FEW DEGREES ON MONDAY.
.LONG TERM...(TUESDAY THROUGH SATURDAY)
ISSUED AT 111 PM MDT SAT MAY 25 2013
TUESDAY...SIMILAR SOUTHWEST FLOW PATTERN ALOFT CONTINUES WITH WEAK
SHORTWAVES ROTATING NORTHEAST ACROSS OUR COUNTIES. SURFACE TROUGH
FORMS FROM CENTRAL WYOMING SOUTHEAST TO EASTERN COLORADO...ACTING AS
A FOCUS FOR ISOLATED TO SCATTERED AFTERNOON AND EVENING
THUNDERSTORMS...SOME STRONG TO POSSIBLY SEVERE.
WEDNESDAY...INITIAL NEGATIVELY TILTED SHORTWAVE TROUGH ALOFT ROTATES
ACROSS OUR COUNTIES AND WITH ADEQUATE LOW AND MID LEVEL
MOISTURE...EXPECT SCATTERED AFTERNOON AND EVENING THUNDERSTORMS
ALONG ITS ASSOCIATED SURFACE TROUGH AXIS.
THURSDAY...SLOW MOVING STACKED UPPER TROUGH LIES ACROSS WYOMING
PRODUCING WEST AND SOUTHWEST WINDS OVER OUR COUNTIES. OUR NORTHERN
AND WESTERN COUNTIES WILL BE CLOSE ENOUGH TO THE UPPER CIRCULATION
FOR SCATTERED LATE DAY SHOWERS AND THUNDERSTORMS...WHILE DOWNSLOPING
WINDS WILL LIMIT AREAL COVERAGE FROM WHEATLAND SOUTH TO COLORADO.
FRIDAY...WINDY AND COOL DAY AS THE MAIN SHORTWAVE TROUGH ALOFT
ROTATES TO OUR EAST...PRODUCING SCATTERED LATE DAY SHOWERS AND
THUNDERSTORMS NORTH OF A DOUGLAS TO SCOTTSBLUFF LINE...WITH
DOWNSLOPING WINDS PRODUCING A RAIN SHADOW EFFECT FURTHER SOUTH.
SATURDAY...LESSER AFTERNOON AND EVENING THUNDERSTORM COVERAGE AS A
WEAK SHORTWAVE RIDGE ALOFT PREVAILS...AND LOW AND MID LEVEL MOISTURE
WANES.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY EVENING)
ISSUED AT 1043 PM MDT SAT MAY 25 2013
VFR FOR AIRPORTS ACROSS SOUTHEAST WYOMING WITH VERY DRY AIR IN
PLACE. A DRY LINE LAYS ALONG THE WYOMING/NEBRASKA BORDER THIS
EVENING AND SHOULD NOT MOVE MUCH OVER THE NEXT 12 TO 18 HOURS. EAST
OF THE LINE...COULD SEE LOWER CEILINGS TOWARDS 10Z WITH MOIST LOW
LEVEL AIR IN PLACE. WENT MVFR WITH CEILINGS AROUND 1500 FEET AT
KCDR AND KAIA. SREF AND HRRR SUPPORT THIS SOLUTION. THEY ALSO SHOW
LOWER CEILINGS POSSIBLY MAKING IT INTO THE KSNY AREA TOWARDS 12Z.
FOR NOW...KEPT THEM VFR AND WE WILL NEED TO MONITOR FOR THE 12Z
TAFS.
&&
.FIRE WEATHER...
ISSUED AT 135 PM MDT SAT MAY 25 2013
A SURFACE BOUNDARY SEPARATING MOIST UNSTABLE AIR TO THE EAST AND
DRY STABLE AIR TO THE WEST WILL EXTEND FROM NORTHEAST WYOMING TO
THE NEBRASKA PANHANDLE. THIS BOUNDARY WILL BE THE FOCUS FOR
THUNDERSTORM DEVELOPMENT THIS AFTERNOON AND EVENING...AND AGAIN
SUNDAY AFTERNOON. DRY CONDITIONS AND GUSTY WINDS WILL CONTINUE
ACROSS MAINLY CARBON AND ALBANY COUNTIES THIS WEEKEND...AND INTO
FAR EASTERN WYOMING BY MONDAY. TEMPERATURES WILL BE 10 TO 15
DEGREES ABOVE NORMAL THROUGH EARLY NEXT WEEK. DUE TO GREEN
FUELS...FIRE WEATHER CONCERNS REMAIN LOW.
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...NONE.
NE...NONE.
&&
$$
UPDATE...WEILAND
SHORT TERM...TJT
LONG TERM...RUBIN
AVIATION...CLAYCOMB
FIRE WEATHER...TJT
AREA FORECAST DISCUSSION
NWS ALBANY NY
645 AM EDT SUN MAY 26 2013
.SYNOPSIS...
A NEARLY STATIONARY LOW PRESSURE AREA IN THE GULF OF MAINE WILL
CONTINUE TO INFLUENCE OUR WEATHER FOR ONE MORE DAY WITH
CLOUDS...SHOWERS AND UNSEASONABLE COOL WEATHER. THIS LOW PRESSURE
AREA WILL SLOWLY LIFT NORTHWARD AND ALLOW FOR HIGH PRESSURE TO
BUILD ACROSS THE REGION FOR MEMORIAL DAY. THEREAFTER...MUCH WARMER
AIR WILL ADVECT INTO EASTERN NEW YORK AND ADJACENT WESTERN NEW
ENGLAND FOR THE MID WEEK PERIOD.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
AS OF 645 AM EDT...LITTLE CHANGES TO THE ONGOING FORECAST AS SHOWER
ACTIVITY HAS GREATLY DIMINISHED AND THE HRRR REFLECTIVITY FORECASTS
CONTINUE TO SUPPORT SCATTERED SHOWERS MAINLY ACROSS THE EASTERN
2/3RDS OF THE CWFA TODAY.
PREV DISC...
CYCLONIC VORTICITY ADVECTION AROUND THE PERIPHERY OF THE GULF OF
MAINE LOW WILL KEEP OUR WEATHER UNSETTLED FOR ONE MORE DAY.
HOWEVER...THE CONCENTRATION OF SHOWERS /PERIODS OF RAIN/ ARE
EXPECTED TO BE LESS THAN SATURDAYS AS THE MAIN DIV-Q ALOFT WEAKENS
THIS MORNING. SO WE WILL CONTINUE WITH ISO-SCT POPS THROUGH THE
BALANCE OF THE DAY. EXPERIENTIAL REFLECTIVITY FORECASTS FROM A
VARIETY OF HI-RES SOURCES CONTINUE TO SUGGEST THE BEST
CONCENTRATION OF SHOWERS WOULD BE ACROSS THE
DACKS...TACONICS...SOUTHERN GREENS AND THE BERKS SO THIS WILL BE
WHERE THE HIGHER POP VALUES WILL BE IN THE GRIDS. ELSEWHERE...A
GRADUAL DECREASE IN COVERAGE AND INTENSITY OF SHOWERS. CLOUDS WILL
REMAIN IN THE FORECAST WITH SOME BREAKS IN THE OVERCAST WEST OF
THE HUDSON RIVER TOWARD SUNSET. WE WILL CONTINUE TO GO WITH THE
COOLER SIDE OF THE GUIDANCE ENVELOPE AS SUGGESTED BY THE LATEST
RUN OF THE LAV/LAMP WHICH WILL BE MAINLY INTO THE 50S FOR VALLEY
LOCATIONS AND SOME UPPER 40S FOR THE HIGHER TERRAIN.
WINDS TODAY WILL REMAIN GUSTY AT TIMES AS MIXING LAYER HEIGHTS
CLIMB TO AT LEAST H850 WHERE 30-35KTS RESIDES.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH TUESDAY/...
THE VERTICALLY STACKED LOW CONTINUES TO FILL AND PER THE GLOBAL
MODELS SHOULD LIFT NORTHWARD LATE THIS EVENING. THIS WILL GREATLY
REDUCE ITS INFLUENCES ACROSS THE REGION WITH CLEARING SKIES FROM
WEST TO EAST. THIS SHOULD THE STAGE FOR THE WINDS TO DECOUPLE AND
NEAR IDEAL RADIATIONAL COOLING CONDITIONS TO EVOLVE. LATEST MOS
GUIDANCE CONTINUES TO ADVERTISE UNSEASONABLY COLD TEMPERATURES
WITH MOST OF THE AREAS DROPPING DOWN INTO THE 30S. PORTIONS OF THE
DACKS AND WESTERN MOHAWK VALLEY ARE EXPECTED TO DROP TO AROUND
FREEZING AND PER COLLABORATION...WE WILL HOIST A FREEZING WARNING
FOR THESE LOCATIONS. ELSEWHERE...OUTSIDE OF THE IMMEDIATE CAPITAL
REGION AND POINTS SOUTHWARD ALONG THE HUDSON RIVER...WE WILL
HOIST FROST ADVISORIES.
THEN HIGH PRESSURE WILL MOVE ACROSS THE REGION MONDAY INTO TUESDAY
WITH A RETURN TOWARD SEASONABLE TEMPERATURES. THERE IS A WINDOW OF
OPPORTUNITY FOR ADDITIONAL FROST/FREEZE HEADLINES NORTH OF THE
CAPITAL REGION MONDAY NIGHT AS WE WILL HIGHLIGHT INTO THE HWO.
HIGHS ON MONDAY WILL RANGE FROM NEAR 70F IN THE VALLEY LOCATIONS
TO 50S-60S ELSEWHERE. TEMPERATURES CONTINUE TO CLIMB ON TUESDAY AS
WE MIX TO H850 WHERE AOA +8C IS EXPECTED WHICH SHOULD ALLOW
SURFACE TEMPS TO CLIMB WELL INTO THE 70S FOR MANY LOCATIONS.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
THE EXTENDED PERIOD WILL FEATURE A WARMING TREND WITH A RETURN TO
ABOVE NORMAL WARMTH BY LATE IN THE WEEK.
RIDGING AT 500 HPA WILL BEGIN TO BECOME STRONGER ACROSS THE OHIO
VALLEY...MID ATLANTIC AND SOUTHEAST FOR THE MID WEEK PERIOD. A
SURFACE WARM FRONT WILL BE PUSHING ACROSS THE AREA FOR LATE TUESDAY
NIGHT INTO WED MORNING...AND A SHORTWAVE WILL SLIDE ACROSS THE TOP
OF RIDGE ACROSS SOUTHERN CANADA ON WEDNESDAY. THESE TWO FEATURES
WILL ALLOW FOR A CHC FOR SOME SHOWERS AND THUNDERSTORMS...ESP FOR
NORTHERN PARTS OF THE REGION. MIN TEMPS ON TUESDAY NIGHT WON/T BE AS
COOL...WITH UPPER 40S TO UPPER 50S. HIGHS ON WED WILL BE MUCH
WARMER...WITH UPPER 70S TO LOW 80S FOR MOST PLACES...AS 850 HPA
TEMPS SURGE TO 13 TO 15 DEGREES C. DEPENDING ON HOW MUCH INSTABILITY
AND SHEAR IS IN PLACE...WE WILL HAVE TO MONITOR THE POTENTIAL FOR
STRONG STORMS ON WEDNESDAY...AS THIS IS A CLIMATOLOGICAL FAVORED
TIME FOR SEVERE WX IN OUR AREA.
TEMPS WILL CONTINUE TO BE WARM FOR THE REMAINDER OF THE WEEK AND
INTO THE WEEKEND WITH MID TO UPPER 80S EXPECTED AS THE REGION
REMAINS DOMINATED BY THE STRONG RIDGE AT 500 HPA...AND 850 HPA TEMPS
WILL BE 15 TO 18 DEGREES C. WITH OUR AREA BEING ON THE NORTHERN
FRINGE OF THE RIDGE...WE WILL HAVE TO WATCH IF ANY ADDITIONAL
SHORTWAVES PASSING ACROSS THE NORTHERN PERIPHERY OF THE RIDGE ALLOW
FOR ADDITIONAL CHANCES FOR THUNDERSTORM ACTIVITY...AS A STATIONARY
SURFACE BOUNDARY SHOULD BE LOCATED JUST NORTH OF THE AREA. FOR
NOW...WILL GO WITH SLIGHT CHC POPS FOR TSTMS FOR THURSDAY AND AGAIN
ON SATURDAY DUE TO THIS POSSIBILITY. OTHERWISE...IT LOOKS TO BE A
WARM AND INCREASINGLY HUMID END TO THE WEEK.
&&
.AVIATION /08Z SUNDAY THROUGH THURSDAY/...
A LOW PRESSURE SYSTEM OFF THE COAST OF MAINE WILL SLOWLY MOVE AWAY
FROM THE REGION ON SUNDAY. BEFORE THIS OCCURS...PERIODS OF RAIN AND
SHOWERS WILL IMPACT THE EASTERN NY AND WESTERN NEW ENGLAND TAF
SITES...MAINLY DURING THE REMAINDER OF THE OVERNIGHT AND INTO THE
MORNING HOURS. ALTHOUGH FLYING CONDITIONS WILL GENERALLY BE VFR FOR
THE VALLEY TAF SITES...THESE PERIODS OF RAIN OR SHOWERS MAY ALLOW
FOR MVFR CONDITIONS AT TIMES...MAINLY FOR CIGS...AS THE RAINFALL
WILL BE RATHER LIGHT. KPSF MAY SEE MORE PERSISTENT MVFR CONDITIONS
THROUGH THE REMAINDER OF THE OVERNIGHT HOURS AND INTO THE FIRST PART
OF SUNDAY MORNING DUE TO LINGERING LOW STRATUS IN PLACE. AT THIS
POINT...IFR CONDITIONS ARE NOT ANTICIPATED FOR ANY OF THE TERMINALS
BASED OFF OF SURROUNDING CONDITIONS AND FORECAST MODEL SOUNDINGS.
BY AFTERNOON...THE THREAT FOR SHOWERS WILL GREATLY DIMINISH...AND
CIGS WILL IMPROVE. VFR CONDITIONS LOOK TO DOMINATE THROUGH THE
AFTERNOON HOURS...AND SKIES WILL BECOME NEARLY CLEAR FOR THE SUNDAY
NIGHT PERIOD.
W-NW WINDS WILL CONTINUE TO BE GUSTY...ESP DURING THE DAYTIME HOURS
ON SUNDAY...WHEN A FEW GUSTS OF 25-30 KTS WILL BE POSSIBLE...ESP FOR
KALB. WINDS WILL DIMINISH ON SUNDAY EVENING AS HIGH PRESSURE MOVES
TOWARDS THE AREA...AND NEARLY CALM WINDS ARE EXPECTED FOR SUNDAY
NIGHT.
OUTLOOK...
SUN NIGHT-TUE...VFR. NO SIG WX.
TUE NIGHT-THU...VFR. BRIEF MVFR/IFR POSSIBLE WITH CHC SHRA/TSRA.
&&
.FIRE WEATHER...
NO FIRE WEATHER CONCERNS INTO EARLY NEXT WEEK DUE TO THE WIDESPREAD
RAINFALL THAT HAS OCCURRED OVER THE PAST FEW DAYS. WINDS WILL BE
NORTHWEST THROUGH TODAY WITH GUSTS OF 25 TO 35 MPH...BECOMING LESS
THAN 10 MPH TONIGHT.
&&
.HYDROLOGY...
RADAR CONTINUES TO EXHIBIT BRIGHT BANDING WHICH IS RESULTING IN
HIGHER RADAR RETURNS BUT RAINFALL AMOUNTS REMAIN RATHER LIGHT PER
REGIONAL AMOUNTS FROM A VARIETY OF SOURCES. 6-HR TOTALS ENDING AT
06Z SUNDAY WHERE LESS THAN 1/2 OF AN INCH WITH AHPS RIVER POINTS
SHOWING EITHER WITHIN SLOW-GRADUAL BANK RISES OR NEAR STEADY
FLOWS. THIS IS EXPECTED TO CONTINUE WITH LITTLE TO NO HYDRO ISSUES
EXPECTED AT THIS TIME. DRIER WEATHER IS EXPECTED LATER TODAY AND
WILL CONTINUE INTO MEMORIAL DAY. THIS WILL RESULT IN AREA STREAMS
AND RIVERS SLOWLY RECEDING EARLY NEXT WEEK.
FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING
OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE
VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON
OUR WEBSITE.
&&
.ALY WATCHES/WARNINGS/ADVISORIES...
CT...FROST ADVISORY FROM MIDNIGHT TONIGHT TO 8 AM EDT MONDAY FOR
CTZ001-013.
NY...FROST ADVISORY FROM MIDNIGHT TONIGHT TO 8 AM EDT MONDAY FOR
NYZ039>041-043-047-048-050-051-054-058-061-063-066-
082>084.
FREEZE WARNING FROM MIDNIGHT TONIGHT TO 8 AM EDT MONDAY FOR
NYZ032-033-038-042.
MA...FROST ADVISORY FROM MIDNIGHT TONIGHT TO 8 AM EDT MONDAY FOR
MAZ001-025.
VT...FROST ADVISORY FROM MIDNIGHT TONIGHT TO 8 AM EDT MONDAY FOR
VTZ013>015.
&&
$$
SYNOPSIS...BGM
NEAR TERM...BGM
SHORT TERM...BGM
LONG TERM...FRUGIS
AVIATION...FRUGIS
FIRE WEATHER...BGM
HYDROLOGY...BGM
FOR THE LATEST UPDATES...PLEASE VISIT OUR WEBPAGE AT
WWW.WEATHER.GOV/ALBANY
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
639 AM CDT SUN MAY 26 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 356 AM CDT SUN MAY 26 2013
THUNDERSTORMS ARE SLOWLY BUILDING INTO SOUTHWEST AND SOUTH CENTRAL
MN EARLY THIS MORNING AS THE LOW LEVEL MOISTURE TRANSPORT IS SLOWLY
VEERING TO OUR SOUTH. THE WORST OF THE STORMS REMAIN FOCUSED NW-SE
ACROSS KFSD... WHERE UP TO 6 INCHES OF RAIN HAS FALLEN OVERNIGHT.
THE 850MB DEW POINT SATURDAY EVENING FROM THE KOMA RAOB WAS 15 DEG
C.
SHORT TERM MODEL GUIDANCE SUGGESTS THE MOISTURE TRANSPORT FOCUSES
FOR A TIME THIS MORNING ACROSS SOUTH CENTRAL MN WITH MULTIPLE ROUNDS
OF CONVECTION POSSIBLE. EVENING RUNS OF THE HRRR WERE VERY BULLISH
ON HEAVY RAINFALL FOR SOUTH CENTRAL MN THIS MORNING.. BUT MORE
RECENT RUNS HAVE BACKED DOWN. OUR MPXWRF AND THE VARIOUS HOPWRF RUNS
SUGGEST THE CONVECTION WEAKENING DURING THE MORNING AS WELL WITH THE
WORST STAYING ACROSS IA. THIS IS IN PART DUE TO THE LOW LEVEL JET
DIMINISHING SOME OVER US... ALONG WITH THE FACT THAT THE BETTER
GRADIENT OF INSTABILITY REMAINS MORE TO OUR WEST AND SOUTH.
THERE SHOULD BE A SIGNIFICANT DROP IN THE PRECIPITATION COVERAGE AND
INTENSITY BY THIS AFTERNOON OVER SOUTHERN MN. HOWEVER... THE SPCWRF
DOES SHOW SHOWERS DEVELOPING OVER CENTRAL MN DURING THE AFTERNOON IN
WHAT SEEMS TIED TO A MCV FROM THE CONVECTION ONGOING OVER CENTRAL SD
ATTM. THEREFORE... SMALL POPS REMAIN FOR THE MN CWA WITH SMALL POPS
SPREADING INTO WEST CENTRAL WI DURING THE LATE AFTERNOON AND
EVENING. LITTLE CHANGE IN THE HIGH TEMPERATURE TODAY WITH AROUND 60
TO MIDDLE 60S FORECAST.
FOR TONIGHT... MORE THUNDERSTORMS WITH HEAVY RAINFALL ARE EXPECTED
TO DEVELOP TO OUR WEST AND SOUTH. THE LOW LEVEL MOISTURE TRANSPORT
IS FOCUSED NEAR THE I-29 CORRIDOR EARLY IN THE NIGHT AND THEN SHIFTS
INTO OUR CWA ON MONDAY. THE SPC/NSSL/NMM AND ARW WRF/S SHOW THE
WORST OF THE CONVECTION TONIGHT ACROSS SD/NE/IA. AT THIS
POINT...POPS TONIGHT INCREASE FROM LOW CHANCE IN THE EVENING TO
LIKELY BY DAYBREAK MONDAY.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 356 AM CDT SUN MAY 26 2013
BEST ADVICE FOR THE LONG TERM...PACK AN UMBRELLA!
AS HAS BEEN THE CASE FOR THE LAST SEVERAL DAYS...MEDIUM RANGE
MODELS CONTINUE TO SHOW A VERY WET AND ACTIVE PATTERN SETTING UP
ACROSS THE NORTHERN PLAINS/UPPER MS VALLEY THROUGH THE COURSE OF NEXT
WEEK. THERE IS STILL GOOD AGREEMENT WITH AN UPPER RIDGE SETTING UP
ON THE EAST COAST OF THE CONUS...AS DEEP TROUGHING REMAINS IN
PLACE ACROSS THE ROCKIES...BEFORE A CLOSED LOW DEVELOPS OVER THE
NORTHERN PLAINS BY THE END OF THE WEEK. DEEP AND MOIST SW FLOW IN
BETWEEN WILL RESULT IN SEVERAL CHANCES FOR THUNDERSTORMS NEXT
WEEK. AS WE HAVE SEEN IN THE SIOUX FALLS AREA THIS EVENING...
FLOODING...BOTH OF THE FLASH AND AREAL/RIVER VARIETY WILL BE
POSSIBLE...ALONG WITH SEVERE WEATHER. FOR SEVERE WEATHER...TUESDAY
THROUGH FRIDAY LOOK TO PROVIDE OPPORTUNITIES FOR SEVERE
WEATHER...WITH THURSDAY AND FRIDAY AT THIS POINT LOOKING TO HAVE
POTENTIAL FOR MORE SIGNIFICANT...OR AT LEAST WIDESPREAD EVENTS.
A KEY COMPONENT FOR THE STORM POTENTIAL THROUGH THE WEEK WILL BE
FRONTAL...ALONG WITH WHAT LOOKS TO BE A VERY ACTIVE LLJ PLACEMENT.
FOR THE WARM FRONT...IT WILL FINALLY START PUSHING INTO MN ON
MONDAY...LIFTING NORTH THROUGH THE MPX CWA DURING THE DAY. THIS
BOUNDARY WILL THEN STALL OUT ACROSS THE AREA ON TUESDAY AND LOOKS
TO WAFFLE AROUND CENTRAL MN INTO NRN WI THROUGH WEDNESDAY.
THURSDAY WILL BRING WITH IT A DEEP SFC LOW INTO NODAK. THIS WILL
FORCE THE WARM FRONT UP INTO CANADA...BUT BEGIN TO SEND A COLD
FRONT ACROSS THE DAKOTAS. THIS SFC LOW WILL BE SLOW MOVING AS IT
BECOMES OCCLUDED OVER SRN MANITOBA THURSDAY NIGHT...WHICH WILL
PULL THE COLD FRONT THROUGH MN ON FRIDAY.
AS FOR PRECIP CHANCES...THEY WILL BE CLOSELY TIED TO WHERE THE LLJ
DECIDES TO SET UP AT ANY PARTICULAR TIME. THE LLJ WILL BE LIFTING
ACROSS MN WITH THE WARM FRONT ON MONDAY...WITH FAIRLY WIDESPREAD
THUNDERSTORMS EXPECTED TO LIFT NORTHEAST THROUGH THE AREA DURING
MEMORIAL DAY AS A RESULT. AT LEAST THIS IS WHAT DETERMINISTIC RUNS
SHOW HAPPENING MEMORIAL DAY. SOMEWHAT CONSPICUOUSLY...THE CAMS SUCH
AS THE NMM AND ARW WERE KEEPING MONDAY DRY WITH THEIR 26.00
RUNS...THOUGH THE FORCING EXPECTED WITH THE WARM FRONT/LLJ WOULD
SUGGEST THE DETERMINISTIC RUNS ARE MORE BELIEVABLE. FOR MONDAY
NIGHT INTO TUESDAY...THE LLJ ANGLES NORTHEAST ACROSS IOWA INTO THE
GREAT LAKES...SO THIS MAY LEAD TO A LULL IN ACTIVITY TUESDAY...WHEN
THE LOWEST POPS OVER THE NEXT WEEK CAN BE FOUND. LLJ BACKS TO THE
SOUTH TUESDAY NIGHT...BRINGING INCREASED THUNDERSTORM CHANCES BY
LATE TUESDAY NIGHT THAT WILL PERSIST THROUGH FRIDAY...WITH THE LLJ
NOT SHOWING SIGNS OF GETTING SHUNTED OFF TO THE EAST OF THE MPX
AREA UNTIL SATURDAY.
FOR SEVERE WEATHER...CIPS ANALOG IMPACT GUIDANCE INDICATING WE
COULD SEE SEVERE WEATHER BASED ON THE TOP 8 MATCHES FROM MONDAY
RIGHT THROUGH WEDNESDAY...THOUGH PROBABILITIES FOR SEVERE WEATHER
ARE MAXIMIZED FOR THURSDAY AND FRIDAY. ON MONDAY...AN ISOLATED
SEVERE HAIL STORM WILL BE POSSIBLE AS THE WARM FRONT LIFTS
NORTH...BUT THIS ACTIVITY LOOKS TO BE ELEVATED AND PRIMARILY
RESPONSIBLE FOR HEAVY RAINFALL. FOR TUESDAY...BEST LLJ FORCING
WILL BE OFF TO THE SE OF THE MPX CWA...BUT WITH A STATIONARY FRONT
PROGGED TO BE ANYWHERE BETWEEN CENTRAL AND SOUTHERN
MINNESOTA...IF SFC BASED CONVECTION WERE TO GET GOING ALONG THIS
BOUNDARY...THEN ALL FORMS OF SEVERE WEATHER WOULD BE POSSIBLE...AS
INDICATED IN THE DAY 3 SPC CONVECTIVE OUTLOOK. YOU CAN MAKE THE
SAME ARGUMENT FOR THE SEVERE WEATHER THREAT ON WEDNESDAY...AS THE
BOUNDARY REMAINS OVER MN...BUT THE ATMOSPHERE IS RELOADING ACROSS
THE DAKOTAS. THURSDAY AND FRIDAY AT THIS POINT ARE THE INTERESTING
DAYS WHERE EVERYTHING LOOKS TO HAVE TO POTENTIAL TO COME IN LINE.
THURSDAY ACROSS MOST OF MN...AND FRIDAY MORE ERN MN INTO WI. BOTH
DAYS...THE GFS/ECMWF SHOW H85 WINDS INCREASING TO OVER 40 KTS OUT
AHEAD OF THE COLD FRONT...HELPING PUSH SFC DEWPS INTO THE UPPER
60S. WIND SHEAR BOTH DAYS THOUGH LOOKS TO BE MAINLY
UNIDIRECTIONAL AND RUNNING PARALLEL TO THE FRONT...WHICH WOULD
FAVOR ACTIVITY BECOMING LINEAR QUITE QUICKLY...ALONG WITH
INCREASING THE HEAVY RAIN/FLOOD POTENTIAL.
AS FOR THAT FINAL HAZARD OF FLOODING...THE ECMWF/GFS CONTINUE TO
PAINT 3 TO 4 INCHES OF RAIN ACROSS JUST ABOUT THE ENTIRE MPX CWA
THROUGH THE COURSE OF NEXT WEEK...WITH 6 PLUS INCH AMOUNTS STILL
INDICATED FOR MUCH OF IOWA. THE MAJORITY OF THAT RAIN WITH THE
26.00 RUNS COMES FROM MONDAY AND AGAIN THURSDAY AND FRIDAY. HAVE
HELD OFF ON ANY FLASH FLOOD WATCHES AT THIS POINT...BUT MONDAY
COULD POSE ISSUES AS THE WARM FRONT LIFTS NORTH. WILL CONTINUE
WITH THE FLOOD MENTION IN THE HWO.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 604 AM CDT SUN MAY 26 2013
MVFR OR LOWER CIGS WILL LIKELY BE MAINTAINED THROUGH THE PERIOD
FROM KAXN THROUGH KRWF. THE MVFR CIGS SHOULD PUSH INTO KSTC THIS
MORNING AND REACH INTO KMSP DURING THE LATE MORNING OR EARLY
AFTERNOON. THE WI TAFS SHOULD HAVE MVFR CIGS DEVELOPING THIS
EVENING. MULTIPLE ROUNDS OF CONVECTION ARE ONGOING ATTM FROM SD
THROUGH IA TO IL. SHORT TERM GUIDANCE SUGGESTS ANY ORGANIZED
CONVECTION STAYING SOUTH OF THE TAF SITES TODAY WITH ISOLATED
THUNDER POSSIBLE FROM KRWF THROUGH ABOUT KRGK THIS MORNING. ITS
THE ACTIVITY IN SD THAT MAY CAUSE A CIRCULATION ALOFT TO MOVE INTO
CENTRAL MN THIS AFTERNOON. IF THIS OCCURS...THEN SHOWERS WOULD
BECOME WIDESPREAD AND THEN PROGRESS INTO EAST CENTRAL MN AND WEST
CENTRAL WI DURING THE LATE AFTERNOON AND EVENING. THIS IS THE
SCENARIO USED IN THE TAFS. BEYOND THIS EVENING CONFIDENCE ON
PRECIP LOCATION AND DURATION DIMINISHES SIGNIFICANTLY DUE TO
CONVECTIVE CONCERNS RETURNING TO OUR WEST AND SOUTH. ONE AREA
WHERE CONFIDENCE REMAINS IS WITH THE CEILINGS BECOMING LOW MVFR
WITH IFR FROM KAXN TO KRWF. STEADY ESE WIND THROUGH THE
PERIOD...STRONGEST ACROSS WEST CENTRAL THROUGH SOUTH CENTRAL MN
WITH 15 TO 25 KNOTS.
KMSP...VFR TO START THE TAF WITH SOME LIGHT SHOWERS AND MVFR
CEILINGS DEVELOPING AFTER 15Z. A MORE ORGANIZED SHOWER EVENT
POSSIBLE DURING THE LATE AFTERNOON AND EVENING WITH CEILINGS
DROPPING BELOW 017 AFTER 06Z. LOW MVFR OR PERHAPS IFR CIGS TO
START MONDAY MORNING ALONG WITH INCREASING CHANCES FOR SHOWERS AND
THUNDERSTORMS. SE WIND THROUGH THE PERIOD AT 12-15 KNOTS WITH
GUSTS TODAY UP TO 25 KNOTS.
/OUTLOOK FOR KMSP/
MON...MVFR OR LOWER CIGS. SHRA/TSRA LIKELY. WINDS SE 10-15 KTS.
TUE...CHC MVFR OR LOWER CIGS. CHC SHRA/TSRA. WINDS SSE 5-10 KTS.
WED...CHC MVFR OR LOWER CIGS. CHC SHRA/TSRA. WINDS S 5-10 KTS.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...RAH
LONG TERM...MPG
AVIATION...RAH
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
716 AM CDT SUN MAY 26 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 331 AM CDT SUN MAY 26 2013
YET ANOTHER COMPLICATED FORECAST FOR TODAY. MOST OF THE CWA IS
VOID OF PRECIPITATION AT THE CURRENT TIME. THE CLOSEST ORGANIZED
AREA OF PRECIPITATION IS A NARROW ELONGATED AREA OF SHOWERS AND
THUNDERSTORMS STRETCHING FROM NORTH CENTRAL IA INTO WEST CENTRAL
IL. THIS ACTIVITY IS LOCATED WITHIN THE GRADIENT OF ELEVATED
INSTABILITY AND IS ASSOCIATED WITH WEAK LOW LEVEL WAA AND MOISTURE
CONVERGENCE VIA A BROAD SWLY LLJ. THIS ACTIVITY MAY SKIRT THE FAR
EASTERN PART OF THE CWA IN THE POST-DAYBREAK PERIOD...OTHERWISE I
THINK THROUGH MID MORNING THAT ANY ACTIVITY WILL BE RATHER
ISOLATED IN COVERAGE. THIS SHOULD CHANGE BEGINNING AROUND MIDDAY
WHEN SCATTERED SHOWERS AND THUNDERSTORMS SHOULD BEGIN TO DEVELOP
...WITH A CONTINUED UPSWING IN COVERAGE THRU THE AFTERNOON IN
RESPONSE TO HEATING/INCREASING INSTABILITY AND INCREASING ASCENT
VIA A DISTURBANCE DROPPING SEWD OUT OF IA FROM THE RIDGE CREST.
THE GREATEST COVERAGE IS EXPECTED TO BE ALONG AND WEST OF THE MS
RIVER...SANS SE MO. DURING THE LATE AFTERNOON INTO THE EARLY
EVENING THERE ARE 2 POSSIBLE SCENARIOS WHICH I ENVISION. THE FIRST
SCENARIO HAS AN MCS EVOLVING ACROSS NE MO/WC IL DUE TO UPSCALE
GROWTH FROM ALL THE SCATTERED CONVECTION DUE TO MERGERS AND COLD
POOL INTERACTION ENHANCED BY THE SSWLY LLJ AND THE DISTURBANCE
ALOFT. THE OTHER PLAUSIBLE SCENARIO IS THE CURRENT MCS OVER NW
IA/SE SD WILL TRACK SEWD TODAY AND THEN MERGE WITH THE
AFOREMENTIONED SCATTERED ACTIVITY IN NE MO/WC IL DURING THE LATE
AFTERNOON. THE END RESULT IN EITHER CASE IS A SEWD MOVING MCS
WHERE THE APEX TRACKS CLOSE TO THE MS RIVER DURING THE EVENING.
THERE COULD ALSO BE ADDITIONAL DEVELOPMENT TONIGHT ON THE TRAILING
FLANK OF THE MCS ACROSS ERN MO DUE TO LIFT VIA THE SWLY
LLJ/MESOSCALE BOUNDARY. IF THIS DOES INDEED OCCUR THERE COULD BE
HEAVY RAIN POTENTIAL...BUT THERE ARE A LOT OF IFS DUE TO MESOSCALE
FACTORS WHICH MUST COINCIDE. THE HRRR AND LAST FEW RUNS OF THE
NCAR 3KM ARW WRF LEND CREDENCE TO THESE SCENARIOS DISCUSSED ABOVE.
GLASS
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 301 AM CDT SUN MAY 26 2013
THERE ARE INDICATIONS IN THE QPF AND MASS FIELDS FROM THE MODELS
ALONG WITH THE AFOREMENTIONED CONVECTION ALLOWING NCAR ARW WRF
THAT AT LEAST THE AREA ALONG AND NORTH OF I-70 COULD BE QUITE ACTIVE
LATE MONDAY MORNING/AFTERNOON. YET ANOTHER DISTURBANCE WILL BE
TRACKING SEWD THRU THE AREA...THE SYNOPTIC SCALE WARM FRONT WILL
BE TRYING TO RETREAT NORTHWARD AND THERE IS POTENTIAL FOR REMNANT
MESOSCALE BOUNDARIES TO FOCUS LIFT - BOTH RESIDENT FROM OVERNIGHT
AND ASSOCIATED WITH DECAYING MCS ACTIVITY MOVING SEWD FROM THE
CENTRAL PLAINS. THE AIR MASS SHOULD ALSO BE MORE UNSTABLE.
IT STILL LOOKS LIKE BY LATE MONDAY NIGHT AND INTO TUESDAY THAT THE
UNSETTLED PATTERN WILL CALM DOWN DUE TO PROGRESSION OF THE UPPER
PATTERN WITH THE UPPER RIDGE SHIFTING INTO THE ERN U.S. AND THE
NORTHWARD RETREAT OF THE WARM FRONT. THIS WILL RESULT IN WARMER
TEMPERATURES AND MAINLY DRY CONDITIONS. AMPLIFICATION OF THE FLOW
ALOFT SHOULD KEEP TEMPERATURES ABOVE NORMAL...WITH A RENEWED
THREAT OF SHOWERS AND THUNDERSTORMS DURING THE LATER PART OF THE
WEEK INTO THE EARLY WEEKEND AS THE WESTERN TROF SHIFTS INTO THE
NATIONS MIDSECTION.
GLASS
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 714 AM CDT SUN MAY 26 2013
STILL HARD TO PIN DOWN TIMING AND COVERAGE OF STORMS THROUGH THE
FORECAST PERIOD. SOME ISOLATED SHOWERS/STORMS HAVE DEVELOPED THIS
MORNING...SO HAVE VCTS MENTION AT KUIN AND VCSH MENTION IN METRO
AREA TAFS...KCOU SHOULD REMAIN DRY. BEST CHANCE FOR STORMS WILL BE
LATER THIS AFTERNOON...SO KEPT VCTS MENTION BEGINNING 19Z-20Z
TIMEFRAME...THEN DIMINISH AFTER 00Z-01Z MONDAY. OTHERWISE...
SOUTHEAST TO SOUTH WINDS TO PERSIST THROUGH THE FORECAST PERIOD.
SPECIFICS FOR KSTL...STILL HARD TO PIN DOWN TIMING AND COVERAGE OF
STORMS THROUGH THE FORECAST PERIOD. SOME ISOLATED SHOWERS/STORMS
HAVE DEVELOPED THIS MORNING...SO HAVE VCSH MENTION IN METRO AREA
TAFS THROUGH 14Z. BEST CHANCE FOR STORMS WILL BE LATER THIS
AFTERNOON...SO KEPT VCTS MENTION BEGINNING AROUND 20Z...THEN
DIMINISH AFTER 01Z MONDAY. OTHERWISE...SOUTHEAST WINDS TO VEER TO
THE SOUTH BY 20Z SUNDAY.
BYRD
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
914 AM EDT SUN MAY 26 2013
.SYNOPSIS...
WEAK HIGH PRESSURE WILL DRIFT ACROSS THE REGION THROUGH THE FIRST
HALF OF THE WEEK AS THE DEEP...COLD UPPER LOW OVER NEW ENGLAND
LIFTS SLOWLY AWAY FROM THE REGION. A WARM FRONT WILL MOVE
NORTHWARD THROUGH THE REGION TUESDAY...ALLOWING BERMUDA HIGH
PRESSURE TO DOMINATE FOR THE LATER HALF OF THE WEEK WITH
INCREASINGLY WARM...HUMID CONDITIONS AND INCREASING CHANCES FOR
AFTERNOON SHOWERS AND THUNDERSTORMS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 905 AM EDT SUNDAY...
WATER VAPOR SATELLITE IMAGERY INDICATES WEAK A WEAK UPPER LEVEL
DISTURBANCE PUSHING SOUTH THROUGH SW VA/NW NC AND SHOULD EXIT BY
15Z. A FEW RETURNS WERE NOTED ON RADAR IN THE NC FOOTHILLS AND A
SOCIAL MEDIA POST CONFIRMS A FEW SPRINKLES WERE FALLING UNDER
THESE ECHOES. PER THE 12Z GSO SOUNDING...THIS VERY LIGHT PRECIP
FALLING UNDER A MID LEVEL 6K FOOT DEPTH MOIST LAYER.
THEREFORE ADDED A MENTION OF SPRINKLES TO THIS AREA THROUGH UNTIL
15Z...WHEN THE 11Z HRRR ENDS THE PRECIP IN OUR FORECAST AREA.
OTHERWISE...PUSHED UP HIGH TEMPS A COUPLE OF DEGREES FOR TODAY AS
WE ARE STARTING MUCH WARMER THAN THIS TIME YESTERDAY AND EXPECT
CLEARING SKIES WITH THE DEPARTING UPPER LEVEL WAVE. THE WARMER
06Z GFS MOS HAD A BETTER HANDLE ON THE PROJECTED 12Z TEMPS VERSUS
THE 06Z NAM MOS...AND ADJUSTED FORECAST HIGHS TOWARD ITS FORECAST
HIGHS FOR TODAY.
THE NEXT NW FLOW DISTURBANCE MOVES TOWARD THE REGION OVERNIGHT
TONIGHT INTO EARLY MONDAY. SFC MOISTURE RECOVERY REMAINS SCANT AS
DEWPOINTS CREEP INTO THE 40S. THUS...STILL DO NOT REALLY EXPECT
MUCH PCPN WITH THIS FEATURE. HOWEVER...THIS DISTURBANCE COMES ON
THE THRESHOLD OF A SIGNIFICANT RISE IN 850MB TEMPS INTO THE +12C
TO +16C RANGE BY MON AFTERNOON...SO WITH STRONGER WAA ADVECTION
AND THE OVERALL BAROCLINIC ZONE SHIFTING MORE INTO THE REGION FROM
THE SOUTH...EXPECT BETTER CHCS FOR -SHRA WITH THIS SYSTEM THAN
WITH THIS MORNINGS. THROUGH 12Z MON...THE ATMOSPHERE WILL REMAIN
ENTIRELY TOO STABLE AND COOL FOR ANY -TSRA...HOWEVER.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
AS OF 430 AM EDT SUNDAY...
FOR MONDAY...WINDS WILL BECOME MORE SOUTHERLY AS HIGH PRESSURE
SHIFTS OFF THE ATLANTIC COAST...WHILE A WARM FRONT MOVES NORTHWARD
ALONG THE OHIO RIVER VALLEY INTO THE CENTRAL APPALACHIAN CHAIN. WITH
STRONGER AFTERNOON HEATING THAN SEEN DURING THE WEEKEND COUPLED WITH
INSTABILITY ASSOCIATED WITH THE FRONT CROSSING OUR AREA...WILL SEE A
CHANCE FOR SHOWERS AND A FEW THUNDERSTORMS DURING THE AFTERNOON AND
EVENING. MODELS ARE ALSO HINTING AT A DISTURBANCE RIDING ALONG THE
FRONT MONDAY NIGHT/EARLY TUESDAY MORNING THAT MAY BRING SPOTTY
SHOWERS NORTHWEST TO SOUTHEAST ACROSS THE AREA...LOOKING LIKE
REMNANTS OF STRONGER ACTIVITY OCCURRING WEST OF THE AREA EARLIER IN
THE EVENING. UNSURE HOW MUCH PRECIPITATION WILL BE LEFT AS THIS
SYSTEM MOVES ACROSS THE MORE STABLE ENVIRONMENT OF OUR AREA...SO
WILL STICK WITH SLIGHT CHANCE WORDING IN THE FORECAST FOR NOW.
BY TUESDAY...THE WARM FRONT WILL HAVE LIFTED NORTH OF OUR AREA...AND
WE WILL ENTER A WEATHER PATTERN OF STRONGER SOUTHWESTERLY WINDFLOW
THAT IS TYPICAL OF WHAT WE SEE DURING THE SUMMER MONTHS. AS SUCH...
LOOKING FOR A ROUND OF AFTERNOON SHOWERS AND THUNDERSTORMS TRIGGERED
BY DAYTIME HEATING...MAINLY ACROSS THE MOUNTAIN RIDGES TO START AND
THEN SPREADING TO THE PIEDMONTS DURING LATE AFTERNOON. COVERAGE WILL
REMAIN SPOTTY AT BEST...AND CONVECTION WILL DIMINISH QUICKLY AFTER
SUNSET.
MORE SHOWER AND THUNDERSTORM ACTIVITY CAN BE EXPECTED FOR
WEDNESDAY...ALTHOUGH COVERAGE IS EXPECTED TO BE A LITTLE MORE
ISOLATED AS UPPER LEVEL RIDGING INCREASES ACROSS THE SOUTHEAST
STATES...ADDING SLIGHTLY MORE STABILITY TO THE ATMOSPHERE.
THE GRADUAL BUILD IN UPPER LEVEL RIDGING THROUGH THE EARLY HALF OF
THE WEEK WILL ALSO LEAD TO WARMING TEMPERATURES...WITH AFTERNOON
HIGHS BY WEDNESDAY RANGING FROM UPPER 70S/LOW 80S ACROSS THE
MOUNTAINS...TO THE MID 80S ACROSS THE PIEDMONTS. LOWS WILL BE IN THE
UPPER 50S TO LOW 60S.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 330 PM EDT SATURDAY...
HEAT WAVE POSSIBLE THROUGH THE END OF NEXT WEEK AS A 590DM UPPER
RIDGE CLOSES OFF OVER THE MIDDLE ATLANTIC IN RESPONSE TO A REX BLOCK
AND CLOSED LOW OVER THE CONTINENTAL DIVIDE. POPS DECREASE THROUGH
THE WEEK WITH SINKING MOTION AND THE PROFILE BECOMING TOO DRY TO
SUPPORT ANYTHING MORE THAN THE MOST ISOLATED THUNDERSTORM ALONG
THE HIGHEST PEAKS BY END WEEK. 90F LOOKS POSSIBLE IN MOST OF THE
CITIES PERHAPS AS EARLY AS THURSDAY. UPPER AIR PATTERN MAY FLATTEN
BY THE END OF NEXT WEEKEND.
&&
.AVIATION /13Z SUNDAY THROUGH THURSDAY/...
AS OF 730 AM EDT SUNDAY...
VFR CIGS EXPECTED THROUGH THE TAF VALID PERIOD. A SERIES OF NW
FLOW DISTURBANCES ON THE BACK SIDE OF THE DEEP NE U.S. UPPER LOW
BRINGING MID/HIGH CLOUDS TO THE SW PART OF THE FORECAST AREA THIS
MORNING. A FEW SPRINKLES NOTED ON KFCX ACROSS NW NC...BUT THESE
WILL NOT AFFECT THE TAF SITES. THE FIRST DISTURBANCE RESPONSIBLE
FOR THE MID/HIGH CLOUDS WILL PASS TO THE S-SE BY LATE
MORNING...TAKING THE CLOUDS WITH IT. SHOULD SEE MOSTLY SKC BY BY
EARLY AFTERNOON AT ALL TAF SITES. THE NEXT DISTURBANCE TO BRING
MID/HIGH CLOUDS WILL ARRIVE AROUND 12Z MON...SO MAINLY IMPACTING
TAFS AFTER THIS TAF VALID PERIOD. AT ANY RATE...CIGS WILL REMAIN
VFR. THE SFC AIR MASS IS BONE DRY...SO NO ISSUES WITH FOG ANYWHERE
THIS MORNING ACROSS THE CWA. FEEL SFC MOISTURE RECOVERY BY 12Z MON
WILL ALSO BE TOO LIMITED TO MENTION ANY FOG AT THIS POINT...SO
VSBYS VFR THROUGH TAF VALID PERIOD. WINDS WNW-NW 5-7KTS
TODAY...CONSIDERABLY LESS THAN THE PAST TWO DAYS. CANNOT RULE OUT
AN ISOLD LOW END GUST DURING THE AFTERNOON...BUT NOT ENOUGH TO
ADVERTISE IN THE TAF. WINDS WILL TRANSITION TO NE AROUND 12Z MON
AS THE SFC HIGH SHIFTS TOWARD THE MID-ATLANTIC COAST.
EXTENDED AVIATION DISCUSSION...MOISTURE INCREASES LATE MON-TUE AS
THE SFC HIGH MOVES EAST AND THE UPPER RIDGE STRENGTHENS OVER THE
MISSISSIPPI VALLEY. A WEAK WARM FRONT/BAROCLINIC ZONE WILL SLIDE
NE ACROSS THE REGION EARLY MON- TUE AHEAD OF THE VERY WARM/MOIST
AIR THAT WILL BE PUSHING IN FROM THE SW. THIS WILL LEAD TO A
SLIGHTLY BETTER SHOT AT SEEING A FEW SHRA/TSRA MONDAY INTO TUESDAY
WITH AT LEAST OROGRAPHIC DRIVEN CONVECTION FOR MID WEEK. PATCHY
LATE NIGHT FOG ALSO LIKELY DURING THE OVERNIGHTS ESPCLY VALLEYS
AND WHERE AFTERNOON/EVENING RAINFALL OCCURS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...RAB
NEAR TERM...RAB
SHORT TERM...PH
LONG TERM...KM
AVIATION...RAB
AREA FORECAST DISCUSSION
NWS SPOKANE WA
843 AM PDT Sun May 26 2013
.SYNOPSIS...
The Pacific Northwest will remain under the influence of a
persistent area of low pressure through latter half of next week.
Showers will be of the scattered variety today and tomorrow. The
arrival of a moist frontal system on Tuesday will bring a better
chance for widespread light rain for eastern Washington and
northern Idaho. This low pressure pattern may break by the end of
the week allowing temperatures to warm closer to average by next
weekend.
&&
.DISCUSSION...
Update: Satellite imagery as of 8 am this morning showed two lows
of interest...one over Vancouver Island and the other moving into
western Oregon. The low over Vancouver Island is expected to be
nearly stationary today...while the low over western Oregon tracks
east into central Oregon this afternoon. The placement of these
two features will result in the bulk of the showers today over the
Cascades during the late morning and afternoon, and from the Blue
Mountains extending northeast towards the Central Panhandle
Mountains in the afternoon. Precipitation chances in these areas
have been adjusted upward slightly based on latest radar trends
and the HRRR showing quite a bit of shower activity moving into
these areas. Models still show potential for isolated
thunderstorms this afternoon mainly over the Blues, Lewiston area,
Palouse, and Central Panhandle Mountains.
Also extensive cloud cover over North Central Washington this
morning and showers expected to move into this area will keep high
temperatures down and forecast values were adjusted accordingly
for places like Wenatchee, Chelan, Winthrop, and Omak. Elsewhere
across the region showers will be more isolated to scattered in
nature with the main adjustment to lower sky cover this morning in
the Sandpoint and Kellogg areas where more extensive cloud cover
will hold off til late morning/early afternoon. JW
&&
.AVIATION...
12Z TAFS: Low pressure will continue to reside over the aviation
area for the next 24 hours. A disturbance passing through it will
allow for cloud along with mostly showers at various times of the
day...additionally some more river fog in valleys and some lowlands
is expected this morning as well. Regardless of the precipitation
or the fog VFR conditions should prevail for most of this time
interval. /Pelatti
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 67 47 66 48 64 47 / 30 20 30 30 50 50
Coeur d`Alene 68 46 65 45 63 45 / 30 40 40 20 50 60
Pullman 64 45 66 47 63 45 / 50 40 20 40 50 50
Lewiston 69 50 73 52 67 50 / 50 40 10 30 50 50
Colville 73 46 70 45 68 46 / 20 20 50 20 50 50
Sandpoint 67 44 64 43 62 43 / 20 40 50 20 50 70
Kellogg 65 46 62 47 59 46 / 40 50 50 20 60 70
Moses Lake 66 49 72 50 72 48 / 40 20 10 30 30 30
Wenatchee 63 50 69 50 70 50 / 50 10 10 30 40 30
Omak 67 46 71 47 69 46 / 30 10 20 30 40 40
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
959 AM CDT SUN MAY 26 2013
.UPDATE...THIS MORNING AND AFTERNOON
ISSUED AT 949 AM CDT SUN MAY 26 2013
A MESOSCALE CONVECTIVE COMPLEX CONTINUES TO MOVE EAST SOUTHEAST
ACROSS SOUTHEAST MINNESOTA AND NORTHEAST IOWA THIS MORNING. THE
HRRR SEEMS TO HAVE A FAIRLY GOOD HANDLE ON THIS SYSTEM...SO USED
IT TO ADD SOME MORE TIMING TO THE HOURLY PRECIPITATION CHANCES FOR
THE REST OF THIS MORNING AND THE AFTERNOON. LIKE YESTERDAY...THE
KARX RADAR IS OVERESTIMATING PRECIPITATION RATES BY 200 TO 300
PERCENT IN BOTH THE LEGACY AND DUAL POLE PRECIPITATION AMOUNT
PRODUCTS...SO CAUTION IS ADVISED WHEN USING THESE PRODUCTS. WHILE
OUR RADAR IS OVERESTIMATING...KDMX RADAR PRECIPITATION TOTAL
PRODUCTS DO LOOK REALISTIC. WITH THE COMPLEX MOVING A BIT FURTHER
NORTH THAN YESTERDAY...EXPECT THE CLOUDS AND PRECIPITATION TO KEEP
THE HIGH TEMPERATURES MAINLY IN THE 50S ALONG ALONG AND SOUTH OF
THE INTERSTATE 90 CORRIDOR.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 230 AM CDT SUN MAY 26 2013
CONVECTION HAS LIT UP DURING THE OVERNIGHT HOURS IN RESPONSE TO THE
SURFACE/850 MB WARM FRONT AND THE IMPINGEMENT OF THE LOW LEVEL
JET/MOISTURE TRANSPORT. HRRR DOING A DECENT JOB WITH THE CURRENT
CONVECTION...AND WILL NUDGE THIS TO LOCATIONS WEST OF THE
MISSISSIPPI RIVER BETWEEN 12-15Z. THIS MATCHES UP WITH THE SPCWRF.
ARWWRF/NAM12 MEANWHILE DECREASE THE AREAL COVERAGE AS IT MOVES EAST
THIS MORNING...BUT STILL HANG ON TO ISOLD/SCT SHOWERS INTO THE
AFTERNOON.
EXPECTATION IS FOR ANOTHER THUNDERSTORM COMPLEX TO DEVELOP OVER THE
CENTRAL PLAINS/WESTERN IA LATER TONIGHT...WITH AN EAST/NORTHEAST
PUSH INTO THE FORECAST AREA.
.LONG TERM...(MONDAY THROUGH SUNDAY)
ISSUED AT 230 AM CDT SUN MAY 26 2013
PRIMARY WEATHER MAKERS FOR THE NEXT FEW DAYS REMAIN UNCHANGED...A
WARM FRONT...POSITION/STRENGTH OF THE LOW LEVEL JET/MOISTURE
TRANSPORT...AND CONVECTION INDUCED MCVS/ENHANCED SHORTWAVE TROUGHS.
WHERE THESE LIE...MOVE...AND MOST IMPORTANTLY...INTERACT...WILL BE
WHERE THE GREATEST THREAT FOR SHOWERS AND THUNDERSTORMS WILL BE.
NAM/GFS/ECMWF HAVE BEEN IN PRETTY GOOD AGREEMENT WITH ADVANCING THE
WARM FRONT...CURRENTLY LYING WEST-EAST ACROSS NORTHERN MO/SOUTHERN
ILL...NORTHWARD ON MONDAY...ENDING UP ACROSS NORTHERN WI LATE WED
NIGHT. THE 850 MB MOISTURE TRANSPORT NOSES INTO/ACROSS THE FRONT ON
MONDAY...BULLSEYEING THE FORECAST AREA. A 500 MB MCV/SHORTWAVE
TROUGH WILL SPIN ACROSS THE PLAINS AND OVER THE UPPER MISSISSIPPI BY
00Z TUES...AIDING SHOWER/STORM DEVELOPMENT.
TUE PROVIDES A SIMILAR SCENARIO WITH A SHORTWAVE TROUGH MOVING IN
FROM THE WEST...BEING ENHANCED FROM CONVECTION SPAWNED FROM THE
MOISTURE TRANSPORT/WARM FRONT INTERACTIONS OVER IA/SOUTHERN MN. THE
FIRST PART OF TUES LOOKS WET AS THE CONVECTIVE COMPLEX FROM LATE
MONDAY MOVES THROUGH. THE LATER 1/2 SHOULD SEE A BREAK FROM
WIDESPREAD RAIN...WITH YET ANOTHER COMPLEX THEN MOVING IN OVERNIGHT
AS CONVECTION SPARKS TO THE WEST.
WED HAS THE WARM FRONT MOVING NORTH OF THE FORECAST AREA...BUT HOW
QUICKLY THIS OCCURS WILL DEPEND ON WHERE THAT EXPECTED RAIN AREA
IS...AND HOW SOON IT EXITS. THIS WOULD SHIFT THE MAIN PCPN FOCUS
TO THE NORTH - ALTHOUGH ONLY BRIEFLY. A SHORT DRYING PERIOD COULD
SEE THE THREAT FOR SHOWERS/STORMS RETURN BY THU
AFTERNOON...CONTINUING INTO FRIDAY. A STRONG PUSH OF LOW LEVEL
MOISTURE WILL REMAIN THE MAIN FIRING MECHANISM...WITH SOME HELP FROM
ENERGY MOVING OUT OF THE UPPER LEVEL TROUGH SITTING TO THE WEST.
DIFFERENCES CONTINUE TO CROP UP BETWEEN THE GFS/EC IN HOW THEY WANT
TO HANDLE THE EVENTUALLY BREAK DOWN/EXIT OF THE TROUGH TO THE WEST
IN THIS RATHER STAGNANT PATTERN. THE GFS REMAINS THE MORE
PROGRESSIVE OF THE SOLUTIONS...WHILE THE EC CONTINUES TO SUGGEST A
CLOSED LOW WOULD DEVELOP...AND SLOW DOWN ITS ALREADY LETHARGIC
STROLL EAST. OBVIOUS IMPLICATIONS IN RAIN CHANCES FOR THE WEEKEND.
WITH CONFIDENCE NOT HIGH IN EITHER OUTCOME...WILL STAY THE COURSE
WITH THE CONSENSUS SOLUTION FOR THE DETAILS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 702 AM CDT SUN MAY 26 2013
VFR CONDITIONS EXPECTED AT THE TAFS SITES THROUGH THIS
AFTERNOON...THEN MVFR/IFR CONDITIONS POSSIBLE LATE TONIGHT INTO
EARLY MONDAY MORNING. SHOWERS AND THUNDERSTORM WILL MOVE ACROSS
PORTIONS OF NORTHEAST IOWA AND SOUTHEAST MINNESOTA THIS
MORNING...MAINLY IMPACTING LOCATIONS SOUTH OF INTERSTATE 90. CANNOT
RULE OUT A SHOWER MOVING ACROSS KRST THROUGH LATE THIS MORNING SO
HAVE INCLUDED VCSH THROUGH 17Z. KLSE SHOULD REMAIN DRY INTO THIS
EVENING. LOWER CEILINGS GRADUALLY BUILD INTO THE TAF SITES TONIGHT
AS A WARM FRONT EDGES NORTHEAST OUT OF THE PLAINS. LOOK FOR
CEILINGS TO LOWER TO AROUND 2KFT BY 01Z AT KRST...THEN FALL TO
AROUND 900 FT AT KRST BY 07Z. ALSO...THUNDERSTORMS WILL DEVELOP
OVER THE DAKOTAS TODAY AND COULD TRACK INTO THE AREA LATE
TONIGHT...IMPACTING THE TAF SITES. CONFIDENCE IS LOW ON THIS
ACTIVITY REACHING KRST AND KLSE EARLY MONDAY MORNING SO HAVE NOT
INCLUDED A THUNDER MENTION IN THE TAFS AT THIS TIME.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...BOYNE
SHORT TERM...RIECK
LONG TERM....RIECK
AVIATION...WETENKAMP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
702 AM CDT SUN MAY 26 2013
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 230 AM CDT SUN MAY 26 2013
CONVECTION HAS LIT UP DURING THE OVERNIGHT HOURS IN RESPONSE TO THE
SURFACE/850 MB WARM FRONT AND THE IMPINGEMENT OF THE LOW LEVEL
JET/MOISTURE TRANSPORT. HRRR DOING A DECENT JOB WITH THE CURRENT
CONVECTION...AND WILL NUDGE THIS TO LOCATIONS WEST OF THE
MISSISSIPPI RIVER BETWEEN 12-15Z. THIS MATCHES UP WITH THE SPCWRF.
ARWWRF/NAM12 MEANWHILE DECREASE THE AREAL COVERAGE AS IT MOVES EAST
THIS MORNING...BUT STILL HANG ON TO ISOLD/SCT SHOWERS INTO THE
AFTERNOON.
EXPECTATION IS FOR ANOTHER THUNDERSTORM COMPLEX TO DEVELOP OVER THE
CENTRAL PLAINS/WESTERN IA LATER TONIGHT...WITH AN EAST/NORTHEAST
PUSH INTO THE FORECAST AREA.
.LONG TERM...(MONDAY THROUGH SUNDAY)
ISSUED AT 230 AM CDT SUN MAY 26 2013
PRIMARY WEATHER MAKERS FOR THE NEXT FEW DAYS REMAIN UNCHANGED...A
WARM FRONT...POSITION/STRENGTH OF THE LOW LEVEL JET/MOISTURE
TRANSPORT...AND CONVECTION INDUCED MCVS/ENHANCED SHORTWAVE TROUGHS.
WHERE THESE LIE...MOVE...AND MOST IMPORTANTLY...INTERACT...WILL BE
WHERE THE GREATEST THREAT FOR SHOWERS AND THUNDERSTORMS WILL BE.
NAM/GFS/ECMWF HAVE BEEN IN PRETTY GOOD AGREEMENT WITH ADVANCING THE
WARM FRONT...CURRENTLY LYING WEST-EAST ACROSS NORTHERN MO/SOUTHERN
ILL...NORTHWARD ON MONDAY...ENDING UP ACROSS NORTHERN WI LATE WED
NIGHT. THE 850 MB MOISTURE TRANSPORT NOSES INTO/ACROSS THE FRONT ON
MONDAY...BULLSEYEING THE FORECAST AREA. A 500 MB MCV/SHORTWAVE
TROUGH WILL SPIN ACROSS THE PLAINS AND OVER THE UPPER MISSISSIPPI BY
00Z TUES...AIDING SHOWER/STORM DEVELOPMENT.
TUE PROVIDES A SIMILAR SCENARIO WITH A SHORTWAVE TROUGH MOVING IN
FROM THE WEST...BEING ENHANCED FROM CONVECTION SPAWNED FROM THE
MOISTURE TRANSPORT/WARM FRONT INTERACTIONS OVER IA/SOUTHERN MN. THE
FIRST PART OF TUES LOOKS WET AS THE CONVECTIVE COMPLEX FROM LATE
MONDAY MOVES THROUGH. THE LATER 1/2 SHOULD SEE A BREAK FROM
WIDESPREAD RAIN...WITH YET ANOTHER COMPLEX THEN MOVING IN OVERNIGHT
AS CONVECTION SPARKS TO THE WEST.
WED HAS THE WARM FRONT MOVING NORTH OF THE FORECAST AREA...BUT HOW
QUICKLY THIS OCCURS WILL DEPEND ON WHERE THAT EXPECTED RAIN AREA
IS...AND HOW SOON IT EXITS. THIS WOULD SHIFT THE MAIN PCPN FOCUS
TO THE NORTH - ALTHOUGH ONLY BRIEFLY. A SHORT DRYING PERIOD COULD
SEE THE THREAT FOR SHOWERS/STORMS RETURN BY THU
AFTERNOON...CONTINUING INTO FRIDAY. A STRONG PUSH OF LOW LEVEL
MOISTURE WILL REMAIN THE MAIN FIRING MECHANISM...WITH SOME HELP FROM
ENERGY MOVING OUT OF THE UPPER LEVEL TROUGH SITTING TO THE WEST.
DIFFERENCES CONTINUE TO CROP UP BETWEEN THE GFS/EC IN HOW THEY WANT
TO HANDLE THE EVENTUALLY BREAK DOWN/EXIT OF THE TROUGH TO THE WEST
IN THIS RATHER STAGNANT PATTERN. THE GFS REMAINS THE MORE
PROGRESSIVE OF THE SOLUTIONS...WHILE THE EC CONTINUES TO SUGGEST A
CLOSED LOW WOULD DEVELOP...AND SLOW DOWN ITS ALREADY LETHARGIC
STROLL EAST. OBVIOUS IMPLICATIONS IN RAIN CHANCES FOR THE WEEKEND.
WITH CONFIDENCE NOT HIGH IN EITHER OUTCOME...WILL STAY THE COURSE
WITH THE CONSENSUS SOLUTION FOR THE DETAILS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 702 AM CDT SUN MAY 26 2013
VFR CONDITIONS EXPECTED AT THE TAFS SITES THROUGH THIS
AFTERNOON...THEN MVFR/IFR CONDITIONS POSSIBLE LATE TONIGHT INTO
EARLY MONDAY MORNING. SHOWERS AND THUNDERSTORM WILL MOVE ACROSS
PORTIONS OF NORTHEAST IOWA AND SOUTHEAST MINNESOTA THIS
MORNING...MAINLY IMPACTING LOCATIONS SOUTH OF INTERSTATE 90. CANNOT
RULE OUT A SHOWER MOVING ACROSS KRST THROUGH LATE THIS MORNING SO
HAVE INCLUDED VCSH THROUGH 17Z. KLSE SHOULD REMAIN DRY INTO THIS
EVENING. LOWER CEILINGS GRADUALLY BUILD INTO THE TAF SITES TONIGHT
AS A WARM FRONT EDGES NORTHEAST OUT OF THE PLAINS. LOOK FOR
CEILINGS TO LOWER TO AROUND 2KFT BY 01Z AT KRST...THEN FALL TO
AROUND 900 FT AT KRST BY 07Z. ALSO...THUNDERSTORMS WILL DEVELOP
OVER THE DAKOTAS TODAY AND COULD TRACK INTO THE AREA LATE
TONIGHT...IMPACTING THE TAF SITES. CONFIDENCE IS LOW ON THIS
ACTIVITY REACHING KRST AND KLSE EARLY MONDAY MORNING SO HAVE NOT
INCLUDED A THUNDER MENTION IN THE TAFS AT THIS TIME.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...RIECK
LONG TERM....RIECK
AVIATION...WETENKAMP
AREA FORECAST DISCUSSION
NWS POCATELLO ID
152 PM MDT SUN MAY 26 2013
.SHORT TERM...TONIGHT THROUGH TUESDAY NIGHT. UPPER TROUGH MOVING
INLAND WITH MAIN CIRCULATION CENTERED OVER OREGON EARLY THIS
AFTERNOON. SHORTWAVE ENERGY EJECTING ACROSS EASTERN IDAHO THIS
AFTERNOON HAS ALLOWED CONVECTION TO DEVELOP OVER PORTIONS OF THE
REGION. STRONGEST CELLS AT THIS TIME ARE LOCATED IN SOUTHWEST
IDAHO..AND SHOULD REACH THE CENTRAL MOUNTAINS BY LATE THIS
AFTERNOON. POTENTIAL STILL EXISTS FOR SMALL HAIL AND GUSTY WINDS.
BEST CHANCES FOR CONVECTION STILL IN THE WESTERN HALF OF THE
FORECAST AREA INCLUDING THE CENTRAL MOUNTAINS. NAM AND HRRR BOTH
EJECT A WEAK LINE OF SHOWERS EAST THROUGH THE SNAKE PLAIN INTO THE
EASTERN HIGHLANDS THIS EVENING AS SHORTWAVE AND MOST OF THE
CONVECTION EXIT NORTHEAST INTO MONTANA. COULD SEE SHOWERS LINGER
ALONG THE DIVIDE AFTER MIDNIGHT. TRANSITORY RIDGE IN PLACE FOR
MONDAY THOUGH THERE IS STILL SOME UNCERTAINTY AS TO TIMING OF NEXT
STRONG SHORTWAVE TROUGH. GFS AND NAM SHOW SIMILAR TIMING WITH THE
MAIN FEATURES BUT GFS SIGNIFICANTLY FASTER WITH QPF SHIELD.
TRENDED TOWARD THE FASTER GFS WITH POPS AS WELL AS COLLABORATION
WITH NEIGHBORS...BRINGING PRECIP BACK TO EASTERN IDAHO BY MONDAY
AFTERNOON. MUCH MORE CONFIDENT IN PRECIP OVERNIGHT MONDAY
NIGHT...AND ESPECIALLY TUESDAY WHICH COULD BE A RATHER WET DAY FOR
THE REGION. SHORTWAVE TROUGH AGAIN LIFTS ACROSS THE REGION AS A
NEGATIVE TILT TROUGH BUT CARRYING A BIT MORE MOISTURE WITH IT.
MODELS PRODUCING WIDESPREAD QPF VALUES OF .10-.25 INCH. THUS KEPT
POPS HIGH TUESDAY INTO TUESDAY NIGHT ALL AREAS. DMH
.LONG TERM...WED THROUGH NEXT SUN NIGHT. THE FIRST 30 HOURS OF THE
LONGWAVE FORECAST DURING THIS PERIOD IS FOR TROUGHING TO CONTINUE
OVER THE NORTHWESTERN UNITED STATES...BUT BY THU THE LONGWAVE IS
MORE ZONAL AND BY LATE THU NIGHT ACTUALLY HAS WEAK RIDGING. THERE
IS A STRONG SHORTWAVE FEATURE MOVING THROUGH THE LONGWAVE PATTERN
DURING THIS TIME. THE ECMWF HAS PULLED BACK FROM ITS HIGH POP DURING
THIS TIME...BUT STILL INDICATES LIKELY FOR WED AND THU IN THE
CENTRAL IDAHO MOUNTAINS AND THE MONTANA BORDER. STILL SIGNIFICANT
PRECIPITATION FORECASTED FOR THE NORTHERN AND EASTERN MOUNTAINS
NORTH OF POCATELLO LATITUDE. THE CLOSED LOW MOVES INTO THE FRONT
RANGE BY THU NIGHT...LEAVING THE EASTERN MOUNTAINS THE MAIN FOCUS OF
PRECIPITATION THEN. BY FRI...LIMITED SHOWER THREAT ALONG THE
NORTHERN ID-WY BORDER...WITH NEARLY CLEAR SKIES IN THE SOUTHWEST
PART OF THE FORECAST AREA...WHICH WILL BE LEAST AFFECTED BY THIS
STORM. SNOW IS STILL POSSIBLE AT EXTREME ELEVATIONS...BUT AMOUNTS
ARE LIGHT ENOUGH WHERE MELTING SHOULD OCCUR DURING THE DAY. THIS
LOW SHOULD BRING SOME WINDY CONDITIONS TO THE SNAKE RIVER PLAIN AND
EASTERN MAGIC VALLEY...AND THE INSTABILITY EACH AFTERNOON IS ENOUGH
TO WARRANT CONTINUING THE ISOLATED TO SCATTERED COVERAGE OF
THUNDERSTORMS. SAT SHOULD BE DRY...WITH ONLY SUN IN SHARP
DISAGREEMENT AMONG PRODUCT SUITES. ECMWF BRINGS ANOTHER STRONG
SHORTWAVE LOW WHILE THE GFS HOLDS THIS LOW IN BRITISH COLUMBIA WITH
A SLOWER EVOLUTION. MESSICK
&&
.AVIATION...SHOWERS IN WESTERN IDAHO HAVE GENERATED SOME ISOLD
LIGHTNING AND WOULD EXPECT THE -TSRA THREAT TO DEVELOP FOR ALL 4
AIRDROMES IN EASTERN IDAHO...DIMINISHING FIRST IN THE WEST AND LATER
IN THE EAST. NOT MUCH EFFECT ON CIG WITH LOWEST EXPECTED STILL
MID-LEVEL. VSBY CONTINUES EXCELLENT AND WINDS SHOULD BE MAINLY
ALONG THE RUNWAY AND ONLY SLIGHTLY GUSTY THIS AFTERNOON AND EVENING.
MESSICK
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
320 PM CDT SUN MAY 26 2013
.DISCUSSION...
ISSUED 252 PM CDT SUN MAY 26 2013
PROLONGED RAINY PERIOD CONTINUES FOR CENTRAL ILLINOIS. THIS
MORNING SHOWERS LINED UP AND REMAINED OVER ONE AREA STRETCHING
FROM JUST SOUTH OF GALESBURG SOUTHEAST TO SHELBYVILLE. AREAS ALONG
THIS AXIS RECD BTWN 2.5 AND 3.5 INCHES OF RAIN...WITH MANY OTHER
LOCATIONS BTWN 1 AND 1.5. WITH MORE RAIN ON THE WAY...CONCERN
INCREASES FOR FLASH FLOODING THREAT. MANY DIFFERENT SOLUTIONS IN
THE SHORT TERM FOR FURTHER DEVELOPMENT AND EVOLUTION OF STORMS.
WITH THE CONVECTIVE RISK AS THE EVENING GOES ON...WILL GO AHEAD
AND ISSUE A FF WATCH FOR PORTIONS OF CENTRAL ILLINOIS THROUGH
TOMORROW. BEYOND THE SHORT TERM...FORECAST INTO THE LONG TERM IS
STILL A CONFLICT OF SYNOPTIC WAVE PATTERNS AT DAY 6/7. FORECAST
OUT THAT FAR A BLEND...WITH CONSIDERATION GIVEN TO UNCERTAINTY.
SHORT TERM...TONIGHT THROUGH TOMORROW...
PLENTY OF PRECIP IN THE CWA THIS MORNING SLOWLY BROKE INTO PIECES
THIS AFTERNOON...THOUGH THE CONVECTIVE ELEMENT IS RETURNING WITH
TS IN THE SW. RAP/RUC AND 4KM WRF SHOWING SOME MAJOR DIFFERENCES
WITH THE EVOLUTION GOING INTO THE EVENING...THOUGH BOTH PRODUCING
SOME RATHER EXTENSIVE QPF. WITH STREAK OF HEAVY PRECIP ALREADY
FROM THIS MORNINGS STORMS FROM SOUTH OF GALESBURG TO
SHELBYVILLE...AND ANOTHER 1 TO 2 INCHES POSSIBLE...AND A
CONVECTIVE ELEMENT TO THE STORMS THIS EVENING POTENTIALLY BUMPING
UP THOSE TOTALS LOCALLY...ISSUING A FF WATCH FOR AFFECTED
COUNTIES. WOULD BE LESS CONCERNED DUE TO THE OVERALL DURATION OF
THE EVENT...BUT 6HR FFG IN THE 2-2.5 INCH RANGE...AND THE
CONVECTIVE ELEMENT ON A HOLIDAY WEEKEND TIP THE SCALE. LONGEVITY
OF PRECIP TOMORROW EVENING VERY MUCH A FUNCTION OF LOCATION OF THE
PASSING WARM FRONT...AND HAVE TERMINATED THE WATCH AT THIS POINT
AT 00Z TOMORROW EVENING. HOWEVER...DEPENDING ON LOCATION OF THE
BOUNDARY AND INTENSITY OF PRECIP...THIS MAY PROVE TO BE TOO
CONSERVATIVE. IN ADDITION TO THAT...SOUTHERLY COMPONENT TO THE
WIND BRINGING WARMER TEMPS IN THE REGION...WITH WARM AIR MOVING IN
AT MIDLEVELS AS THE EAST SIDE OF THE UPPER RIDGE ERODES SOMEWHAT.
WARM FRONT FORWARD PROGRESSION INTO THE REGION MAY BE TEMPERED QUITE A BIT BY
RAIN COOLED AIR AS THE RAIN/CONVECTION GOES ON ALL DAY. VERY
SIMILAR TO TODAY...AND HIGHS WILL BE REACHED AT VARYING POINTS
THROUGHOUT THE DAY DEPENDING ON WHERE THE STORMS/CLOUDS ARE. IN
SHORT...FORECAST IS PROBLEMATIC IN AN HOURLY SENSE TO SAY THE
LEAST. THOUGH WARMER THAN TODAY...KEEPING THE TEMPS A BIT BELOW
GUIDANCE...AND THE GEMNH HAS ACTUALLY PROVIDED A VERY POSSIBLE
SOLUTION CONSIDERING THE GRADIENT FROM NE TO SW.
LONG TERM...TUESDAY THROUGH SATURDAY...
DEPENDING ON THE INTERACTION BTWN COLD POOLS AND THE SFC BOUNDARY...LOCATION
OF THE SFC WARM FRONT A BIT OF A QUESTION MARK ON TUESDAY MORNING.
POPS REMAIN PREDOMINANTLY IN THE NORTH...INVOF THE BOUNDARY.
FORECAST ACTUALLY DRY FROM TUES NIGHT THROUGH WED NIGHT. WESTERN
TROF DIGS IN...AMPLIFYING THE WAVE PATTERN OVER THE CONUS AND
LEAVING THE UPPER MIDWEST IN SWRLY FLOW...AND MUCH OF IL IN WEAK
FLOW...IF ANY...UNDER THE BUILDING RIDGE. VERY WARM MIDLEVELS AND
THE GUIDANCE STARTING TO REFLECT THE SITUATION A LITTLE BETTER. RETURNING
POPS ON THURS NIGHT/FRI SHOWING MORE OF A DELAY THAN THE 00Z
RUN...AS IT HAS THE PAST FEW CYCLES. A BIT MORE CONFIDENCE FOR
THUR NIGHT...AND FRIDAY SPECIFICALLY...WITH A COLD FRONT PASSAGE
FRI NIGHT. STILL A DEBATE AS THE GFS AND ECMWF QUITE DIFFERENT IN
HANDLING THE LARGE SCALE WAVE IN RELATION TO THE SFC SYSTEM.
HJS
&&
.AVIATION...
ISSUED 1248 PM CDT SUN MAY 26 2013
CONVECTION CONTINUES TO WEAKEN AS IT PUSHES THROUGH EASTERN
ILLINOIS...AND SHOULD SEE MOST OF IT OUT OF THE TAF SITES BY 20Z.
HAVE THEN GONE WITH DRY CONDITIONS THROUGH JUST AFTER SUNSET. HAVE
BEEN SEEING SOME BRIEF IFR CONDITIONS DROPPING SOUTHEAST FROM THE
MISSISSIPPI RIVER TO AROUND KSPI. HRRR MODEL SHOWS SOME EROSION OF
THIS OVER THE NEXT COUPLE HOURS...BUT HAVE INCLUDED TEMPO IFR
CEILINGS FOR THE FIRST FEW HOURS OF THE FORECAST.
AS WITH THE LAST COUPLE NIGHTS...THE CHALLENGE WILL BE WITH
CONVECTIVE REDEVELOPMENT THIS EVENING AS LOW LEVEL JET KICKS BACK
IN. HAVE LEANED TOWARD THE RAP MODEL AS IT SEEMED TO DO FAIRLY
WELL WITH THE MORNING ACTIVITY...AND HIT KPIA/KBMI THE HARDEST
WITH TSRA AND MVFR CONDITIONS...WITH THE 04-08Z TIME FRAME MOST
FAVORED. KSPI MAY ALSO BE IMPACTED BUT IS ON THE EDGE...SO DID
NOT GO WITH TOO LOW OF CONDITIONS YET. KDEC/KCMI ALSO ON THE FENCE
AND ONLY MENTIONED VCTS/VCSH FOR NOW.
GEELHART
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1248 PM CDT SUN MAY 26 2013
.DISCUSSION...
ISSUED 1009 AM CDT SUN MAY 26 2013
NORTHWEST-SOUTHEAST ORIENTED BAND OF CONVECTION HAS BEEN WEAKENING
SOME AS THE LOW-LEVEL JET WANES. HAVE SEEN 1 TO 1.5 INCHES IN THE
HEAVIER BANDS SINCE 7 AM FROM FULTON COUNTY SOUTHEAST TO JUST EAST
OF SPRINGFIELD...WHEN THE STORMS WERE NOT AS PROGRESSIVE AS THEY
ARE NOW. REDEVELOPMENT TAKING PLACE WEST OF SPRINGFIELD IN AREAS
THAT HAD BEEN DRY FOR A COUPLE HOURS. HIGH-RESOLUTION MODELS ARE
FAIRLY AGREEABLE WITH TRENDS FOR THE NEXT FEW HOURS...BUT DIFFER A
BIT ON PLACEMENT OF ADDITIONAL DEVELOPMENT THIS AFTERNOON FURTHER
WEST...AND ITS POTENTIAL IMPACT EARLY THIS EVENING. FOR NOW...HAVE
EMPHASIZED THE HIGHEST POPS THROUGH EARLY AFTERNOON...WITH SOME
GRADUAL DECREASE LATER. ALSO UPDATED THE TEMPERATURE TRENDS AND
LOWERED HIGHS A BIT IN THE NORTH...BUT WILL HAVE TO WATCH THIS
CLOSELY AS THEY BE MUCH LOWER IF THE RAIN HOLDS ON TOO LONG...
SIMILAR TO YESTERDAY.
UPDATED ZONES/GRIDS HAVE BEEN SENT.
GEELHART
&&
.AVIATION...
ISSUED 1248 PM CDT SUN MAY 26 2013
CONVECTION CONTINUES TO WEAKEN AS IT PUSHES THROUGH EASTERN
ILLINOIS...AND SHOULD SEE MOST OF IT OUT OF THE TAF SITES BY 20Z.
HAVE THEN GONE WITH DRY CONDITIONS THROUGH JUST AFTER SUNSET. HAVE
BEEN SEEING SOME BRIEF IFR CONDITIONS DROPPING SOUTHEAST FROM THE
MISSISSIPPI RIVER TO AROUND KSPI. HRRR MODEL SHOWS SOME EROSION OF
THIS OVER THE NEXT COUPLE HOURS...BUT HAVE INCLUDED TEMPO IFR
CEILINGS FOR THE FIRST FEW HOURS OF THE FORECAST.
AS WITH THE LAST COUPLE NIGHTS...THE CHALLENGE WILL BE WITH
CONVECTIVE REDEVELOPMENT THIS EVENING AS LOW LEVEL JET KICKS BACK
IN. HAVE LEANED TOWARD THE RAP MODEL AS IT SEEMED TO DO FAIRLY
WELL WITH THE MORNING ACTIVITY...AND HIT KPIA/KBMI THE HARDEST
WITH TSRA AND MVFR CONDITIONS...WITH THE 04-08Z TIME FRAME MOST
FAVORED. KSPI MAY ALSO BE IMPACTED BUT IS ON THE EDGE...SO DID
NOT GO WITH TOO LOW OF CONDITIONS YET. KDEC/KCMI ALSO ON THE FENCE
AND ONLY MENTIONED VCTS/VCSH FOR NOW.
GEELHART
&&
.PREV DISCUSSION...
ISSUED 318 AM CDT SUN MAY 26 2013
SHORT TERM...TODAY THROUGH TUESDAY
LATEST REGIONAL RADAR MOSAIC SHOWED CONVECTION LIGHTING UP FROM NW
IOWA SOUTHEAST INTO WEST CENTRAL IL. THIS WAS OCCURRING WELL NORTH
OF A STATIONARY SURFACE BOUNDARY WHICH BISECTED MISSOURI FROM NW TO
SE...AND FOCUSED ALONG A STRONG THERMAL GRADIENT AT 850 MB. MORE
SIGNIFICANT ACTIVITY IN IA WAS BEING FED BY ELEVATED INSTABILITY
FROM A 35 KT LLJ...WITH COVERAGE AND INTENSITY FADING FARTHER EAST
INTO CENTRAL IL AS THIS SUPPORT DIMINISHED. HOWEVER THIS MAY
INCREASE OVER THE WESTERN CWA FOR THE NEXT FEW HOURS AS THE LLJ
VEERS. THIS CONVECTION HAS A HISTORY OF TRAINING IN EASTERN
IA AND WITH OBSERVED RAIN RATES UP TO 0.75 IN/HR SOME LOCALIZED
HEAVIER AMOUNTS OF 1-2 INCHES CERTAINLY POSSIBLE...MAINLY WEST OF
THE IL RIVER. LATEST 4KM NSSL WRF HAD BEST HANDLE ON THIS CONVECTION
AND WOULD FAVOR BEST STORM COVERAGE OVER THE WESTERN HALF OF THE
CWA THIS MORNING...GRADUALLY LIFTING NORTH AND DIMINISHING BY
MIDDAY. FOCUS FOR NEW PRECIP GENERATION THROUGH AFTERNOON WOULD BE
TIED TO ANOTHER SHORTWAVE CROSSING INTO WEST CENTRAL IL BY 18Z.
TEMPS TODAY SHOULD BE SEVERAL DEGREES WARMER THAN YESTERDAY WITH
MORE OF A SOUTHEAST WIND COMPONENT. HAVE TRENDED TOWARD COOLER MAV
GUIDANCE WITH EXPECTED CLOUD COVER FOR HIGHS STILL SEVERAL DEGREES
BELOW NORMAL IN THE UPPER 60S/LOWER 70S.
FOR TONIGHT THROUGH MONDAY...THE SURFACE FRONT CURRENTLY TO OUR
SOUTHWEST WILL LIFT NORTH INTO THE CWA. THUS WILL MAINTAIN A
CONTINUED CHANCE OF SCATTERED STORMS AS SEVERAL MID LEVEL WAVES
ARE FORECAST TO SHIFT OVER THE CWA. EXTENT OF COLUMN SATURATION
AND P/W RISING OVER 1.5 INCHES SUGGESTS LOCALLY HEAVY RAIN
POSSIBLE PRIMARILY OVER THE NW CWA WHERE FORCING IS SHOWN TO BE
STRONGEST.
THE FRONT IS FORECAST TO LIFT INTO NORTHERN IL ON TUESDAY...AND
THIS SHOULD FOCUS MOST OF THE HIGHER PRECIP CHANCES TO OUR NORTH.
HOWEVER WITH UNCERTAINTY ON HOW QUICKLY THE FRONT LIFTS NORTH
DUE TO EXPECTED CONVECTION AND OUTFLOW...WILL KEEP LOW CHC POPS
FOR THE NORTH INTO TUESDAY. OTHERWISE...BRISK SOUTHERLY FLOW WILL
BRING A MUCH WARMER INTO CENTRAL IL WITH HIGHS GETTING WELL INTO
THE 80S.
LONG TERM...WEDNESDAY THROUGH SATURDAY
BY MID-WEEK THE UPPER AIR PATTERN WILL FEATURE A SUB-TROPICAL
RIDGE STRENGTHENING OVER THE CAROLINAS...WHILE A LOW CLOSES OFF
OVER THE NORTHERN ROCKIES. RESULTING DEEP LAYER SOUTHWEST FLOW
WILL CONTINUE TO PUMP WARM AIR INTO THE REGION AND WITH DEWPOINTS
WELL INTO THE 60S...A STRETCH OF SUMMER-LIKE WEATHER WILL SET UP
OVER THE MIDWEST FOR THE END OF MAY. THE MAIN QUESTION FOR THE
EXTENDED FORECAST IS HOW QUICKLY THE RIDGE OVER THE EAST COAST
BREAKS DOWN...ALLOWING THE LARGE TROF TO THE WEST TO SHIFT INTO
THE UPPER MIDWEST. CURRENT INDICATIONS SHOW AN ACTIVE SETUP FROM
THE PLAINS POSSIBLY AS FAR EAST AS IOWA AND MISSOURI FOR THURSDAY
AND FRIDAY AS A SURFACE LOW LIFTS INTO THE PLAINS AND AN
ASSOCIATED COLD FRONT SLOWLY WORKS EAST INTO THE WARM AND UNSTABLE
AIRMASS. WILL KEEP A LOW CHANCE POP ACROSS THE WEST THU/FRI TO
ACCOUNT FOR ANY ACTIVITY TO OUR WEST THAT MAKES IT THIS FAR EAST
IN A DECAYING FASHION. THE BEST SHOT AT MORE WIDESPREAD STORMS
APPEARS TO BE NEXT WEEKEND WHEN THE RIDGE FINALLY SHIFTS EAST INTO
THE ATLANTIC AND THE UPPER TROF AND SFC FRONT CAN GET INTO THE
CWA. OF COURSE MUCH UNCERTAINTY THAT FAR OUT WITH THE EC ENSEMBLE
MEAN SHOWING A MUCH WEAKER TROF BY 192 HRS. TEMPS WILL REMAIN WELL
ABOVE NORMAL UNTIL THE COLD FRONT EVENTUALLY PASSES.
25
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
212 PM CDT SUN MAY 26 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 356 AM CDT SUN MAY 26 2013
THUNDERSTORMS ARE SLOWLY BUILDING INTO SOUTHWEST AND SOUTH CENTRAL
MN EARLY THIS MORNING AS THE LOW LEVEL MOISTURE TRANSPORT IS SLOWLY
VEERING TO OUR SOUTH. THE WORST OF THE STORMS REMAIN FOCUSED NW-SE
ACROSS KFSD... WHERE UP TO 6 INCHES OF RAIN HAS FALLEN OVERNIGHT.
THE 850MB DEW POINT SATURDAY EVENING FROM THE KOMA RAOB WAS 15 DEG
C.
SHORT TERM MODEL GUIDANCE SUGGESTS THE MOISTURE TRANSPORT FOCUSES
FOR A TIME THIS MORNING ACROSS SOUTH CENTRAL MN WITH MULTIPLE ROUNDS
OF CONVECTION POSSIBLE. EVENING RUNS OF THE HRRR WERE VERY BULLISH
ON HEAVY RAINFALL FOR SOUTH CENTRAL MN THIS MORNING.. BUT MORE
RECENT RUNS HAVE BACKED DOWN. OUR MPXWRF AND THE VARIOUS HOPWRF RUNS
SUGGEST THE CONVECTION WEAKENING DURING THE MORNING AS WELL WITH THE
WORST STAYING ACROSS IA. THIS IS IN PART DUE TO THE LOW LEVEL JET
DIMINISHING SOME OVER US... ALONG WITH THE FACT THAT THE BETTER
GRADIENT OF INSTABILITY REMAINS MORE TO OUR WEST AND SOUTH.
THERE SHOULD BE A SIGNIFICANT DROP IN THE PRECIPITATION COVERAGE AND
INTENSITY BY THIS AFTERNOON OVER SOUTHERN MN. HOWEVER... THE SPCWRF
DOES SHOW SHOWERS DEVELOPING OVER CENTRAL MN DURING THE AFTERNOON IN
WHAT SEEMS TIED TO A MCV FROM THE CONVECTION ONGOING OVER CENTRAL SD
ATTM. THEREFORE... SMALL POPS REMAIN FOR THE MN CWA WITH SMALL POPS
SPREADING INTO WEST CENTRAL WI DURING THE LATE AFTERNOON AND
EVENING. LITTLE CHANGE IN THE HIGH TEMPERATURE TODAY WITH AROUND 60
TO MIDDLE 60S FORECAST.
FOR TONIGHT... MORE THUNDERSTORMS WITH HEAVY RAINFALL ARE EXPECTED
TO DEVELOP TO OUR WEST AND SOUTH. THE LOW LEVEL MOISTURE TRANSPORT
IS FOCUSED NEAR THE I-29 CORRIDOR EARLY IN THE NIGHT AND THEN SHIFTS
INTO OUR CWA ON MONDAY. THE SPC/NSSL/NMM AND ARW WRF/S SHOW THE
WORST OF THE CONVECTION TONIGHT ACROSS SD/NE/IA. AT THIS
POINT...POPS TONIGHT INCREASE FROM LOW CHANCE IN THE EVENING TO
LIKELY BY DAYBREAK MONDAY.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 356 AM CDT SUN MAY 26 2013
BEST ADVICE FOR THE LONG TERM...PACK AN UMBRELLA!
AS HAS BEEN THE CASE FOR THE LAST SEVERAL DAYS...MEDIUM RANGE
MODELS CONTINUE TO SHOW A VERY WET AND ACTIVE PATTERN SETTING UP
ACROSS THE NORTHERN PLAINS/UPPER MS VALLEY THROUGH THE COURSE OF NEXT
WEEK. THERE IS STILL GOOD AGREEMENT WITH AN UPPER RIDGE SETTING UP
ON THE EAST COAST OF THE CONUS...AS DEEP TROUGHING REMAINS IN
PLACE ACROSS THE ROCKIES...BEFORE A CLOSED LOW DEVELOPS OVER THE
NORTHERN PLAINS BY THE END OF THE WEEK. DEEP AND MOIST SW FLOW IN
BETWEEN WILL RESULT IN SEVERAL CHANCES FOR THUNDERSTORMS NEXT
WEEK. AS WE HAVE SEEN IN THE SIOUX FALLS AREA THIS EVENING...
FLOODING...BOTH OF THE FLASH AND AREAL/RIVER VARIETY WILL BE
POSSIBLE...ALONG WITH SEVERE WEATHER. FOR SEVERE WEATHER...TUESDAY
THROUGH FRIDAY LOOK TO PROVIDE OPPORTUNITIES FOR SEVERE
WEATHER...WITH THURSDAY AND FRIDAY AT THIS POINT LOOKING TO HAVE
POTENTIAL FOR MORE SIGNIFICANT...OR AT LEAST WIDESPREAD EVENTS.
A KEY COMPONENT FOR THE STORM POTENTIAL THROUGH THE WEEK WILL BE
FRONTAL...ALONG WITH WHAT LOOKS TO BE A VERY ACTIVE LLJ PLACEMENT.
FOR THE WARM FRONT...IT WILL FINALLY START PUSHING INTO MN ON
MONDAY...LIFTING NORTH THROUGH THE MPX CWA DURING THE DAY. THIS
BOUNDARY WILL THEN STALL OUT ACROSS THE AREA ON TUESDAY AND LOOKS
TO WAFFLE AROUND CENTRAL MN INTO NRN WI THROUGH WEDNESDAY.
THURSDAY WILL BRING WITH IT A DEEP SFC LOW INTO NODAK. THIS WILL
FORCE THE WARM FRONT UP INTO CANADA...BUT BEGIN TO SEND A COLD
FRONT ACROSS THE DAKOTAS. THIS SFC LOW WILL BE SLOW MOVING AS IT
BECOMES OCCLUDED OVER SRN MANITOBA THURSDAY NIGHT...WHICH WILL
PULL THE COLD FRONT THROUGH MN ON FRIDAY.
AS FOR PRECIP CHANCES...THEY WILL BE CLOSELY TIED TO WHERE THE LLJ
DECIDES TO SET UP AT ANY PARTICULAR TIME. THE LLJ WILL BE LIFTING
ACROSS MN WITH THE WARM FRONT ON MONDAY...WITH FAIRLY WIDESPREAD
THUNDERSTORMS EXPECTED TO LIFT NORTHEAST THROUGH THE AREA DURING
MEMORIAL DAY AS A RESULT. AT LEAST THIS IS WHAT DETERMINISTIC RUNS
SHOW HAPPENING MEMORIAL DAY. SOMEWHAT CONSPICUOUSLY...THE CAMS SUCH
AS THE NMM AND ARW WERE KEEPING MONDAY DRY WITH THEIR 26.00
RUNS...THOUGH THE FORCING EXPECTED WITH THE WARM FRONT/LLJ WOULD
SUGGEST THE DETERMINISTIC RUNS ARE MORE BELIEVABLE. FOR MONDAY
NIGHT INTO TUESDAY...THE LLJ ANGLES NORTHEAST ACROSS IOWA INTO THE
GREAT LAKES...SO THIS MAY LEAD TO A LULL IN ACTIVITY TUESDAY...WHEN
THE LOWEST POPS OVER THE NEXT WEEK CAN BE FOUND. LLJ BACKS TO THE
SOUTH TUESDAY NIGHT...BRINGING INCREASED THUNDERSTORM CHANCES BY
LATE TUESDAY NIGHT THAT WILL PERSIST THROUGH FRIDAY...WITH THE LLJ
NOT SHOWING SIGNS OF GETTING SHUNTED OFF TO THE EAST OF THE MPX
AREA UNTIL SATURDAY.
FOR SEVERE WEATHER...CIPS ANALOG IMPACT GUIDANCE INDICATING WE
COULD SEE SEVERE WEATHER BASED ON THE TOP 8 MATCHES FROM MONDAY
RIGHT THROUGH WEDNESDAY...THOUGH PROBABILITIES FOR SEVERE WEATHER
ARE MAXIMIZED FOR THURSDAY AND FRIDAY. ON MONDAY...AN ISOLATED
SEVERE HAIL STORM WILL BE POSSIBLE AS THE WARM FRONT LIFTS
NORTH...BUT THIS ACTIVITY LOOKS TO BE ELEVATED AND PRIMARILY
RESPONSIBLE FOR HEAVY RAINFALL. FOR TUESDAY...BEST LLJ FORCING
WILL BE OFF TO THE SE OF THE MPX CWA...BUT WITH A STATIONARY FRONT
PROGGED TO BE ANYWHERE BETWEEN CENTRAL AND SOUTHERN
MINNESOTA...IF SFC BASED CONVECTION WERE TO GET GOING ALONG THIS
BOUNDARY...THEN ALL FORMS OF SEVERE WEATHER WOULD BE POSSIBLE...AS
INDICATED IN THE DAY 3 SPC CONVECTIVE OUTLOOK. YOU CAN MAKE THE
SAME ARGUMENT FOR THE SEVERE WEATHER THREAT ON WEDNESDAY...AS THE
BOUNDARY REMAINS OVER MN...BUT THE ATMOSPHERE IS RELOADING ACROSS
THE DAKOTAS. THURSDAY AND FRIDAY AT THIS POINT ARE THE INTERESTING
DAYS WHERE EVERYTHING LOOKS TO HAVE TO POTENTIAL TO COME IN LINE.
THURSDAY ACROSS MOST OF MN...AND FRIDAY MORE ERN MN INTO WI. BOTH
DAYS...THE GFS/ECMWF SHOW H85 WINDS INCREASING TO OVER 40 KTS OUT
AHEAD OF THE COLD FRONT...HELPING PUSH SFC DEWPS INTO THE UPPER
60S. WIND SHEAR BOTH DAYS THOUGH LOOKS TO BE MAINLY
UNIDIRECTIONAL AND RUNNING PARALLEL TO THE FRONT...WHICH WOULD
FAVOR ACTIVITY BECOMING LINEAR QUITE QUICKLY...ALONG WITH
INCREASING THE HEAVY RAIN/FLOOD POTENTIAL.
AS FOR THAT FINAL HAZARD OF FLOODING...THE ECMWF/GFS CONTINUE TO
PAINT 3 TO 4 INCHES OF RAIN ACROSS JUST ABOUT THE ENTIRE MPX CWA
THROUGH THE COURSE OF NEXT WEEK...WITH 6 PLUS INCH AMOUNTS STILL
INDICATED FOR MUCH OF IOWA. THE MAJORITY OF THAT RAIN WITH THE
26.00 RUNS COMES FROM MONDAY AND AGAIN THURSDAY AND FRIDAY. HAVE
HELD OFF ON ANY FLASH FLOOD WATCHES AT THIS POINT...BUT MONDAY
COULD POSE ISSUES AS THE WARM FRONT LIFTS NORTH. WILL CONTINUE
WITH THE FLOOD MENTION IN THE HWO.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 158 PM CDT SUN MAY 26 2013
MVFR CIGS SHOULD BE EXPECTED THROUGH MUCH OF THE FORECAST PERIOD.
SPORADIC VERY LIGHT SHOWERS WILL ALSO BE ENCOUNTERED THROUGH THE
EARLY EVENING HOURS...WITH MDT SE FLOW SLACKENING CONSIDERABLY
AFT 23Z. SURFACE CYCLONE MOVES INTO WESTERN NE AND KS BY 27/06Z
TIME PERIOD. OVERNIGHT SETTING UP SIMILAR TO PREVIOUS TWO...AS
WARM FRONTAL BOUNDARY STILL BACKBONE OF PRECIPITATION SHIELD
INITIATION. DIFFERENCE THIS GO AROUND WILL BE CLOSER PROXIMITY
OF WARM FRONTAL BOUNDARY TO OUR REGION...WITH BEST CHANCE FOR
LIGHT TO MODERATE SHOWER ACTIVITY OCCURRING BETWEEN 04Z AND 09Z
WITH OF COURSE WESTERN AIRPORT SITES COMMENCING FIRST. LOW MVFR
CIGS WILL KICK IN WITH THIS ACTIVITY AND CONTINUE INTO LATE
IN THE PERIOD...WITH HIGH MVR CIGS ANTICIPATED AFTER ABOUT 16Z.
MORE WIDESPREAD CONVECTION WILL OCCUR AFTER 19Z ON MONDAY
...ESPECIALLY SOUTH OF A RWF-KMSP LINE.
KMSP...MAINLY VFR VSBYS AND MVFR CIGS EXPECTED THROUGH END
OF PERIOD. LIGHT -RW AND OR DRIZZLE NOTED FROM NEAR KSTC
TO KMSP TO JUST WEST OF KEAU. EXPECT THIS REGION TO GROW
SLIGHTLY IN INTENSITY AND COVERAGE PRIOR TO 00Z...ASSOCIATED
WITH LATE DAY HEATING AND CONTINUED UNSTABLE ATMOSPHERE
AHEAD OF SURFACE WARM BOUNDARY OVER EASTERN SODAK. SE FLOW
WILL CONTINUE INTO END OF PERIOD. MVFR CIGS WILL SLOWLY
DESCEND TO NEAR 1000 FEET BY 06Z TIME FRAME...WITH HIGH
END MVFR RETURNING BY 17Z. ALTHOUGH NOT DISPLAYED IN CURRENT
TAF...EXPECT MORE WIDESPREAD -SHRA AFTER 27/20Z TIME PERIOD
...AND RETURN TO MID RANGE MVFR CIGS.
/OUTLOOK FOR KMSP/
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...RAH
LONG TERM...MPG
AVIATION...AJZ
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1233 PM CDT SUN MAY 26 2013
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 331 AM CDT SUN MAY 26 2013
YET ANOTHER COMPLICATED FORECAST FOR TODAY. MOST OF THE CWA IS
VOID OF PRECIPITATION AT THE CURRENT TIME. THE CLOSEST ORGANIZED
AREA OF PRECIPITATION IS A NARROW ELONGATED AREA OF SHOWERS AND
THUNDERSTORMS STRETCHING FROM NORTH CENTRAL IA INTO WEST CENTRAL
IL. THIS ACTIVITY IS LOCATED WITHIN THE GRADIENT OF ELEVATED
INSTABILITY AND IS ASSOCIATED WITH WEAK LOW LEVEL WAA AND MOISTURE
CONVERGENCE VIA A BROAD SWLY LLJ. THIS ACTIVITY MAY SKIRT THE FAR
EASTERN PART OF THE CWA IN THE POST-DAYBREAK PERIOD...OTHERWISE I
THINK THROUGH MID MORNING THAT ANY ACTIVITY WILL BE RATHER
ISOLATED IN COVERAGE. THIS SHOULD CHANGE BEGINNING AROUND MIDDAY
WHEN SCATTERED SHOWERS AND THUNDERSTORMS SHOULD BEGIN TO DEVELOP
...WITH A CONTINUED UPSWING IN COVERAGE THRU THE AFTERNOON IN
RESPONSE TO HEATING/INCREASING INSTABILITY AND INCREASING ASCENT
VIA A DISTURBANCE DROPPING SEWD OUT OF IA FROM THE RIDGE CREST.
THE GREATEST COVERAGE IS EXPECTED TO BE ALONG AND WEST OF THE MS
RIVER...SANS SE MO. DURING THE LATE AFTERNOON INTO THE EARLY
EVENING THERE ARE 2 POSSIBLE SCENARIOS WHICH I ENVISION. THE FIRST
SCENARIO HAS AN MCS EVOLVING ACROSS NE MO/WC IL DUE TO UPSCALE
GROWTH FROM ALL THE SCATTERED CONVECTION DUE TO MERGERS AND COLD
POOL INTERACTION ENHANCED BY THE SSWLY LLJ AND THE DISTURBANCE
ALOFT. THE OTHER PLAUSIBLE SCENARIO IS THE CURRENT MCS OVER NW
IA/SE SD WILL TRACK SEWD TODAY AND THEN MERGE WITH THE
AFOREMENTIONED SCATTERED ACTIVITY IN NE MO/WC IL DURING THE LATE
AFTERNOON. THE END RESULT IN EITHER CASE IS A SEWD MOVING MCS
WHERE THE APEX TRACKS CLOSE TO THE MS RIVER DURING THE EVENING.
THERE COULD ALSO BE ADDITIONAL DEVELOPMENT TONIGHT ON THE TRAILING
FLANK OF THE MCS ACROSS ERN MO DUE TO LIFT VIA THE SWLY
LLJ/MESOSCALE BOUNDARY. IF THIS DOES INDEED OCCUR THERE COULD BE
HEAVY RAIN POTENTIAL...BUT THERE ARE A LOT OF IFS DUE TO MESOSCALE
FACTORS WHICH MUST COINCIDE. THE HRRR AND LAST FEW RUNS OF THE
NCAR 3KM ARW WRF LEND CREDENCE TO THESE SCENARIOS DISCUSSED ABOVE.
GLASS
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 301 AM CDT SUN MAY 26 2013
THERE ARE INDICATIONS IN THE QPF AND MASS FIELDS FROM THE MODELS
ALONG WITH THE AFOREMENTIONED CONVECTION ALLOWING NCAR ARW WRF
THAT AT LEAST THE AREA ALONG AND NORTH OF I-70 COULD BE QUITE ACTIVE
LATE MONDAY MORNING/AFTERNOON. YET ANOTHER DISTURBANCE WILL BE
TRACKING SEWD THRU THE AREA...THE SYNOPTIC SCALE WARM FRONT WILL
BE TRYING TO RETREAT NORTHWARD AND THERE IS POTENTIAL FOR REMNANT
MESOSCALE BOUNDARIES TO FOCUS LIFT - BOTH RESIDENT FROM OVERNIGHT
AND ASSOCIATED WITH DECAYING MCS ACTIVITY MOVING SEWD FROM THE
CENTRAL PLAINS. THE AIR MASS SHOULD ALSO BE MORE UNSTABLE.
IT STILL LOOKS LIKE BY LATE MONDAY NIGHT AND INTO TUESDAY THAT THE
UNSETTLED PATTERN WILL CALM DOWN DUE TO PROGRESSION OF THE UPPER
PATTERN WITH THE UPPER RIDGE SHIFTING INTO THE ERN U.S. AND THE
NORTHWARD RETREAT OF THE WARM FRONT. THIS WILL RESULT IN WARMER
TEMPERATURES AND MAINLY DRY CONDITIONS. AMPLIFICATION OF THE FLOW
ALOFT SHOULD KEEP TEMPERATURES ABOVE NORMAL...WITH A RENEWED
THREAT OF SHOWERS AND THUNDERSTORMS DURING THE LATER PART OF THE
WEEK INTO THE EARLY WEEKEND AS THE WESTERN TROF SHIFTS INTO THE
NATIONS MIDSECTION.
GLASS
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1204 PM CDT SUN MAY 26 2013
SCT THUNDERSTORMS ARE EXPECTED TO DEVELOP THIS AFTN WITHIN A MOIST
AND UNSTABLE AIR MASS. BEYOND THE END OF THE 24HR TAF PD...THERE
IS A CHANCE OF THUNDERSTORMS TOMORROW AFTN. SELY WINDS WILL BECOME
SLY ONCE A WARM FRONT LIFTS NORTH OF THE TERMINALS. STRONGER WINDS
ALOFT WILL MIX DOWN TO THE SURFACE TOMORROW AND PRODUCE WIND GUSTS
OF 20-25 KTS.
SPECIFICS FOR KSTL...SCT THUNDERSTORMS ARE EXPECTED TO DEVELOP
THIS AFTN WITHIN A MOIST AND UNSTABLE AIR MASS. VCTS LOOKS
APPROPRIATE FOR KSTL ATTM GIVEN THE EXPECTED AREAL COVERAGE. WILL
AMEND THE TAF IF RADAR IMAGERY SHOWS ANY STORMS HEADING TOWARDS
KSTL. THERE IS A CHANCE OF THUNDERSTORMS TOMORROW AFTN AS WELL.
SELY WINDS WILL BECOME SLY ONCE A WARM FRONT LIFTS NORTH OF THE
TERMINAL. STRONGER WINDS ALOFT WILL MIX DOWN TO THE SURFACE
TOMORROW AND PRODUCE WIND GUSTS OF 20-25 KTS.
KANOFSKY
&&
.LSX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
IL...NONE.
&&
$$
WFO LSX
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
315 PM CDT SUN MAY 26 2013
.SYNOPSIS...
A DEEP UPPER LEVEL LOW...CURRENTLY ACROSS THE NORTH PACIFIC...WILL
MIGRATE SLOWLY EAST THROUGH THE PACIFIC NORTHWEST AND INTO THE NRN
PLAINS THIS WEEK. A STRONG PACIFIC COLD FRONT WILL MOVE THROUGH
THE FCST AREA WEDNESDAY NIGHT OR THURSDAY. SEVERE WEATHER IS
POSSIBLE TODAY THROUGH WEDNESDAY AS LOW PRESSURE REMAINS QUASI
STATIONARY ACROSS ERN COLORADO AND FOCUSES...MOSITURE...WARM AIR
ADVECTION AND DRY.
&&
.DISCUSSION...
TONIGHT AND MONDAY...CONVECTION LATE THIS AFTERNOON INTO THE
EVENING TONIGHT...THEN LOW CLOUDS FOG DEVELOPMENT TOWARD MORNING
REMAIN FORECAST ISSUES FOR THE SHORT TERM. WEAK COLD FRONT
ANALYZED FROM SOUTHWEST NEBRASKA SOUTHWARD INTO NW KS AND ERN CO.
WARM FRONT EXTENDS FROM SW INTO SC NEBRASKA WITH INVERTED TROUGH
NORTHWARD INTO SD. NUMEROUS OUTFLOW BOUNDARIES SHOW IN THE HAND
ANALYSIS AS WELL.
QUITE A VARIED RANGE OF SHORT TERM MODEL SOLUTIONS FOR THIS EVENING
AS HRRR AND HIRES ARW SUGGEST NOTHING ORGANIZED WILL DEVELOP SOUTH
OF I80 CORRIDOR...BUT DEVELOP A MCS ACROSS THE SANDHILLS IN THE
HIGHWAY 2 VCNTY AND MOVE IT EASTWARD OVERNIGHT. THE NAM /AND HIRES
NMM/ AS WELL AS GFS SUGGEST TWO AREAS OF DEVELOPMENT...THE FIRST IN
SIMILAR AREAS TO THE PREVIOUSLY MENTIONED MODELS /SANDHILLS/ AND A
SECOND IN THE VCNTY OF THE WARM FRONT WHICH ORGANIZES INTO A MCS AND
MOVES SOUTHEAST. FCST WILL GO WITH THE IDEA THAT TO SOME DEGREE BOTH
GROUPS OF SOLUTIONS HAVE REALISTIC POSSIBILITIES BASED ON BETTER DEEP
LAYER SHEAR ACROSS THE NORTH WHICH SHOULD ALLOW FOR A BETTER
ORGANIZATION ONCE DEVELOPMENT OCCURS IN THE SANDHILLS BY EVENING.
LOW LEVEL LAPSE RATES IN THIS AREA HOWEVER ARE NOT THE BEST AS WOULD
BE EXPECTED NORTH OF THE WARM FRONT...AND ALSO BELIEVE AIR MASS IS
STILL SOMEWHAT INFLUENCED IN THE LOW LAYERS AS A RESULT OF THE
OUTFLOW THAT WAS EVIDENT EARLIER THIS MORNING. LARGE HAIL STILL A
POSSIBILITY HERE THOUGH WITH VERY STEEP MID LEVEL LAPSE RATES...EVEN
IF STORMS ARE ELEVATED WHICH SEEMS LIKELY IN THIS AREA.
FURTHER SOUTH...LOW LEVEL LAPSE RATES ARE STEEPEST ACROSS ERN CO AND
NW KS AND HAVE SURGED EWD AHEAD OF LEE SFC LOW IN NW KS. GOOD
THETA-E ADVECTION NORTHEAST OF THIS AREA SHOULD ALLOW DEVELOPMENT IN
THIS AREAS AS WELL...THOUGH COVERAGE REMAINS IN QUESTION. SPC
MESOANALYSIS INDICATES SOME CAP STILL PRESENT HERE AND SINCE LARGE
SCALE FORCING IS BEST FURTHER NORTH THE EXTENT OF CAP EROSION IS
ALSO IN QUESTION. WOULD LIKE TO SEE BETTER SFC CONVERGENCE IN THESE
LOCATIONS TO BE MORE CERTAIN ABOUT INITIATION. IF SFC BASED
DEVELOPMENT DOES OCCUR SVR POTENTIAL WILL BE HIGH AS VERY GOOD ML
CAPE IS IN PLACE. THEREFORE...FCST INCLUDES POPS IN THESE AREAS BASED ON
PREVIOUS THINKING.
THE LAST FEW NIGHTS HAS SEEN A TENDENCY TO DEVELOP LOW CLOUD BEHIND
OUTFLOW BOUNDARIES TWD DAYBREAK AND BELIEVE THAT SHOULD BE THE CASE
ONCE AGAIN MONDAY MORNING. DEPICTING LOCATIONS IS DIFFICULT BUT
FAVORED AREAS EAST OF HIGHWAY 61 SEEM MOST LIKELY AND HAVE TRENDED
THE FCST THAT WAY. EVENTUAL HIGH TEMPS WILL BE HIGHLY DEPENDENT ON
THESE LOW CLOUD DEVELOPMENT AS WELL...BUT AS WITH THE LAST FEW DAYS
AFTERNOON MIXING SHOULD ALLOW 80S MOST PLACES.
CONVECTION AGAIN POSSIBLE MONDAY AFTERNOON. MODELS SUGGESTING UPPER
TROUGH WILL CONTINUE TO MOVE EASTWARD AND SHOULD ALLOW FOR A MORE
SOUTHERN LOCATION OF SFC FEATURES ONCE CONVECTIVE DEBRIS GIVES WAY.
SOMEWHAT BETTER UPPER PV ANOMALY LOOKS TO SWING OUT ONTO THE PLAINS
BY LATE AFTERNOON MONDAY.
MONDAY NIGHT THROUGH WEDNESDAY...
SFC LOW PRESSURE WILL REMAIN TUCKED ACROSS ERN COLO FOCUSING
MOISTURE...DRY AIR AND WARM AIR ADVECTION ACROSS WRN AND NCNTL NEB.
THE SFC LOW WILL GRADUALLY DEEPEN TO AROUND 992 MB BY TUESDAY AND
CONTINUING NEAR 992 MB THROUGH WEDNESDAY. A PACIFIC FRONT SHOULD
MOVE INTO WRN NEB LATE WEDNESDAY. THROUGH WEDNESDAY...500 MB HEIGHTS
WILL GRADUALLY FALL WHILE H700 MB TEMPS REMAIN NEAR STEADY AT
10C-12C. WIND SHEAR APPEARS TO GRADUALLY INCREASE SUPPORTING A
SLIGHT INCREASE IN BULK SHEAR. NEARLY ALL OF THE FCST AREA HAS BEEN
OUTLOOKED FOR SEVERE WEATHER BY SPC THROUGH WEDNESDAY. ALL
CONVECTION WHICH DEVELOPS TONIGHT THROUGH WEDNESDAY WILL HAVE A
LARGE IMPACT ON SUBSEQUENT STORM DEVELOPMENT AS RAIN COOLED OUTFLOW
DEVELOPS AND SETS UP FOCUS FOR SUCCEEDING STORM DEVELOPMENT. THUS THE
LOCATION OF HIGHEST POPS IS HIGHLY CONDITIONAL. A MULTI MODEL BLEND
WAS USED FOR POPS AND CAPPED AT 40 PERCENT. A SIMILAR STRATEGY WAS
USED FOR QPF. IN GENERAL NRN AND WRN NEB APPEAR MORE FAVORABLE FOR
STORM DEVELOPMENT THAT THE SOUTHWEST WHERE 700 MB WARM AIR ADVECTION
WILL OFTEN CAP THE ATMOSPHERE.
A SERIES OF PERTURBATIONS WILL CONTINUE TO EJECT FROM THE UPPER LOW
ACROSS THE NRN PACIFIC. THESE DISTURBANCES WILL MOVE THROUGH SD AND
NEB TRIGGERING STORM DEVELOPMENT. IN TIME THE UPPER LEVEL WILL BUILD
SOUTHEAST THROUGH PACIFIC NORTHWEST AND NRN ROCKIES. FALLING HEIGHTS
SHOULD MAINTAIN STEEP LAPSE RATES AND AN EML CONDUCIVE FOR STORM
DEVELOPMENT. AS LONG AS THE PACIFIC FRONT REMAINS WEST OF THE FCST
AREA...MOISTURE AND WARM AIR ADVECTION SHOULD CONTINUE PROVIDING
FUEL FOR STORM DEVELOPMENT.
WITH THE PERSISTENT MOISTURE ADVECTION...K INDICES INCREASE TO 40C
OR GREATER IN THE NAM AND GFS MODELS. THIS ALONG WITH THE FACT THAT
VERY HEAVY RAINFALL TOTALS HAVE OCCURRED FROM STORMS THIS LAST TWO
DAYS...SUGGEST SOME STORMS WILL PRODUCE LOCALLY HEAVY RAINFALL.
WEDNESDAY NIGHT THROUGH MONDAY MORNING...
THE PACIFIC FRONT WILL LIKELY CROSS THE FCST AREA WEDNESDAY
NIGHT...EARLY THURSDAY AT THE LATEST. THIS WILL SHUNT LOW LEVEL
MOISTURE EAST OF THE FCST AREA. H500 MB TEMPS FALL TO AROUND -18C
WHICH WOULD CONTINUE TO SUPPORT SHOWERS AND THUNDERSTORMS. THE
MODELS ARE IN GOOD AGREEMENT THAT AN UPPER LEVEL LOW WILL CIRCULATE
THROUGH THE NRN AND CNTL PLAINS. ALTHOUGH THE COLD CORE WILL LIKELY
CENTER ACROSS ND/SD...THERE SHOULD BE ENOUGH COLD AIR ALOFT ACROSS
THE FCST AREA TO DESTABILIZE THE ATMOSPHERE THURSDAY AND
FRIDAY...PERHAPS EVEN SATURDAY.
FCST MAX TEMPS WILL RISE INTO THE 60S AND 70S BEHIND THE FRONT
THURSDAY THROUGH MONDAY.
&&
.AVIATION...FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED
AT 1241 PM CDT SUN MAY 26 2013
TIMING OF TSRA REMAINS THE MAIN FCST CHALLENGE WITH TAFS...ALONG
WITH POST CONVECTION CLOUD COVER. FOG DISSIPATING ABOUT ON
SCHEDULE IN THE KVTN AREA THOUGH LOW CLOUDS LINGER. TSRA CHANCES
INCREASE IN LATE AFTERNOON..THOUGH HAVE MOVED FCST TSRA FROM
PREVAILING CONDITION FOR NOW BASED ON THE IDEA THAT DEVELOPMENT
WILL OCCUR FURTHER WEST AND MOVE INTO THE TAF AREA SO COVERAGE IS
IN QUESTION. AFTER CONVECTION WANES BELIEVE...AS HAS BEEN THE CASE
THE LAST FEW NIGHTS...LOW CLOUDS AND POSSIBLY FOG WILL REDEVELOP
TOWARD SUNRISE. FOR THE KLBF TAF SITE...ALSO BELIEVE TSRA CHANCES
ENTER THE PICTURE THIS EVENING...THOUGH COVERAGE AGAIN REMAINS IN
QUESTION. VSBYS IN TSRA SHOULD BE LOWER AT KLBF AS HIGH MOISTURE
CONTENT TO CLOUDS SHOULD YIELD HIGHER RAINFALL RATES AND HENCE
REDUCED VSBYS. AGAIN...LOW CLOUD DEVELOPMENT SHOULD OCCUR AFTER
THE CONVECTIVE DEBRIS EXISTS.
&&
.LBF WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...JWS
LONG TERM...CDC
AVIATION....JWS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
318 PM CDT SUN MAY 26 2013
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 320 PM CDT SUN MAY 26 2013
FORECAST PROBLEM IN THE SHORT TERM WILL BE THUNDERSTORM CHANCES
THROUGH THE PERIOD. OVERALL MODEL TREND HAS BEEN TO LESSEN OR PUSH
BACK PRECIPITATION CHANCES ESPECIALLY LATE THIS AFTERNOON AND THIS
EVENING. BEYOND THIS THERE IS LITTLE FORECAST CONFIDENCE REGARDING
PRECIPITATION TIMING AND PLACEMENT AS MODELS ARE HAVING A HARD TIME
RESOLVING THIS IN THE BROAD SOUTHWEST UPPER FLOW.
CURRENTLY...MVFR-IFR STRATUS REMAIN ACROSS THE SOURIS TO JAMES
RIVER BASINS...WHILE STRATUS HAS DISSIPATED BUT WELL DEVELOPED CU
FIELD HAS BROKEN OUT OVER THE WEST AND SOUTH CENTRAL. THIS HAS
RESULTED IN TEMPERATURES PUSHING INTO THE LOW TO MID 70S WITH MID
50S DEWPOINT TEMPERATURES FROM WESTERN NORTH DAKOTA INTO EASTERN
MONTANA AND NORTHWEST SOUTH DAKOTA. CURRENT SPC ANALYSIS IS
SHOWING CAPES OF 1000-1500 J/KG WITH DIMINISHING CIHN OVER THE
MONDAK REGION WITH INCREASING LAPSE RATES. CONVECTION HAS RECENTLY
INITIATED OVER THE BIGHORNS AND BLACK HILLS. GGW 18Z SOUNDING AND
CURRENT LAPS SOUNDING NEAR KOLF INDICATE A NEAR COMPLETE ERODED
CAP OVER EASTERN MONTANA. LATEST WATER VAPOR SATELLITE IMAGERY
SHOW AN APPROACHING SHORTWAVE TROUGH LIFTING NORTHEAST THROUGH
WYOMING WHICH SHOULD HELP TO INITIATE CONVECTION AWAY FROM THE
MOUNTAINS. WITH THIS SAID...MODELS ARE NOT POINTING TO STRONG
CONVECTION OVER WESTERN AND CENTRAL NORTH DAKOTA THIS AFTERNOON
AND EARLY EVENING. GFS/ECMWF BRING BEST CHANCES INTO THE FAR WEST
LATE TONIGHT WITH CONVECTION CONTINUING EAST ACROSS THE AREA ON
MONDAY. 12 UTC NAM AND 17 UTC HRRR BRING CONVECTION FIRING OFF THE
BIGHORNS INTO SOUTHEAST MONTANA BUT THEN SUPPRESS REFLECTIVITIES
AS THEY MOVE INTO WESTERN NORTH DAKOTA. 12 UTC HIRES ARW/NMM EAST
BOTH POINT MORE TOWARD LATE NIGHT CONVECTION MOVING INTO THE WEST
AND LINGERING INTO MONDAY...WITH YET ANOTHER ROUND OF CONVECTION
ON MONDAY.
FOR NOW WILL LEAN TOWARD SLIGHT CHANCE POPS EAST TO CHANCE POPS
WEST THIS EVENING...THEN INCREASING AFTER MIDNIGHT WITH HIGHEST
POPS REMAINING IN THE WEST. THEN BASICALLY A BROAD BRUSH OF HIGH
CHANCE POPS ON MONDAY DUE TO SO MUCH UNCERTAINTY ON
TIMING/PLACEMENT. WITH AFOREMENTIONED SEVERE WEATHER INGREDIENTS
WILL KEEP A MENTION OF SEVERE LATE THIS AFTERNOON AND THIS
EVENING. IF CONVECTION WOULD DEVELOP AND MOVE INTO WESTERN NORTH
DAKOTA...THE GREATEST THREAT WOULD LIKELY BE LARGE HAIL AND VERY
HEAVY RAIN CAUSING LOCALIZED FLOODING PROBLEMS.
ALTHOUGH SPC SLIGHT RISK DOES INCLUDE A PORTION OF THE FAR
SOUTHWEST ON MONDAY...WILL HOLD OFF ON MENTIONING THIS IN THE
FORECAST FOR NOW. WILL LET LATER SHIFTS RE-EVALUATE.
MODELS DO INDICATE INCREASING 925MB MOISTURE TONIGHT. CONSIDERED
ADDING A MENTION OF FOG...BUT THINK THE BIGGEST ISSUE WILL BE LOW
STRATUS AND LIFR CEILINGS. COULD SEE SOME MVFR VISIBILITIES BUT
WILL HOLD OFF ON ADDING FOG FOR NOW.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 320 PM CDT SUN MAY 26 2013
A VERY ACTIVE WEATHER PATTERN WILL PERSIST ACROSS THE NORTHERN
PLAINS THROUGH MUCH IF NOT ALL OF THE EXTENDED PERIOD.
LONG WAVE TROUGH WEST AND RIDGING EAST WILL MAINTAIN SOUTHWESTERLY
FLOW ALOFT ACROSS THE DAKOTAS MONDAY NIGHT. SHOWERS AND POSSIBLY
SEVERE THUNDERSTORMS WILL BE ONGOING AT THE START OF THE PERIOD
MONDAY EVENING AS A STRONG S/WV LIFTS NORTHEAST THROUGH THE REGION.
SCALED BACK PRECIPITATION CHANCES TUESDAY/TUESDAY EVENING AS A S/WV
RIDGE ADVANCES NORTHEAST THROUGH THE STATE ALONG WITH DRIER AIR INTO
MY WEST. SHOWER/THUNDERSTORM CHANCES INCREASE TUESDAY NIGHT AS THE
RIDGE CONTINUES OFF TO OUR NORTH AND EAST RESULTING IN FLOW ALOFT
TRANSITIONING TO SOUTHWEST ONCE AGAIN...WITH A LEAD IMPULSE MOVING
NORTH THROUGH THE WESTERN DAKOTAS.
BY WEDNESDAY MORNING THE BASE OF THE WESTERN CONUS TROUGH WILL BE
OVER THE SOUTHERN ROCKIES...WHICH IS DEPICTED BY BOTH THE 12Z
GFS/ECMWF TO SWING NORTH THROUGH THE CENTRAL PLAINS INTO THE DAKOTAS
WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT. FOR THURSDAY...THE BASE OF
THE TROUGH MORPHS INTO A CUTOFF LOW WHICH MAY LINGER ACROSS THE
NORTHERN PLAINS INTO SATURDAY IF THE 12Z ECMWF VERIFIES. THE 12Z GFS
IS MORE PROGRESSIVE...WITH THE LOW BECOMING AN OPEN WAVE AND MOVING
OVER THE WESTERN GREAT LAKES REGION BY SATURDAY MORNING. BOTH MODEL
SOLUTIONS RESULT IN HIGH CHANCES FOR SHOWERS AND THUNDERSTORMS
WEDNESDAY-WEDNESDAY NIGHT-THURSDAY...WITH A CHANCE OF STRONG TO
SEVERE STORMS AS WELL. FORECAST UNCERTAINTY INCREASES AFTERWARDS FOR
FRIDAY THROUGH THE WEEKEND WITH THE ABOVE MENTIONED DIFFERENCES
BETWEEN THE GFS/ECMWF.
TEMPERATURES WILL AVERAGE NEAR TO SLIGHTLY ABOVE NORMAL EARLY NEXT
WEEK...THEN WILL AVERAGE NEAR TO SLIGHTLY BELOW NORMAL FOR THE END
OF THE WORK WEEK THROUGH NEXT WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 320 PM CDT SUN MAY 26 2013
FOR THE 18Z TAF ISSUANCE...SOUTHEAST FLOW WILL CONTINUE THROUGH
THE FORECAST PERIOD. THIS WILL KEEP A THREAT OF MVFR-IFR CEILINGS
IN THE FORECAST AT ALL TAF SITES. VFR CONDITIONS TO START AT
KISN...KDIK AND KBIS...WITH MVFR-IFR CEILINGS AT KMOT AND KJMS.
EXPECT A GRADUAL LIFTING OF CEILINGS AT KJMS AND KMOT. DEVELOPING
CU FIELD WILL LIKELY BRING BKN MVFR CEILINGS BACK TO KBIS AND KDIK
BY 20Z...WITH PERHAPS A FEW HOURS OF VFR CEILINGS AT ALL TAF SITES
FROM LATE AFTERNOON INTO MID EVENING. MODELS ALL AGREE ON BRINGING
ABUNDANT LOW LEVEL MOISTURE BACK INTO THE AREA TONIGHT SO BROUGHT
CEILINGS DOWN TO IFR-LIFR AROUND 06-10Z AT ALL SITES...WITH SOME
MVFR FOG. THINK LIFT STRATUS WILL BE THE GREATER THREAT...RATHER
THAN VISIBILITIES. THEN BROUGHT MAINLY MVFR CEILINGS AFTER 16Z
MONDAY. KEPT A MENTION OF SHOWERS AND VCTS OVER KDIK AND KISN FOR
NOW LATE EVENING INTO EARLY MORNING MONDAY.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...TWH
LONG TERM...NH
AVIATION...TWH
AREA FORECAST DISCUSSION
NWS AMARILLO TX
405 PM CDT SUN MAY 26 2013
.DISCUSSION...
THERE REMAINS A LARGE AMOUNT OF POTENTIAL FOR WEATHER ACROSS THE
PANHANDLES FOR THE NEXT SEVERAL DAYS BUT THE QUESTION WILL BE CAN WE
TURN THAT POTENTIAL INTO REALITY.
ACROSS THE NORTHWEST TEXAS AND WESTERN OKLAHOMA PANHANDLE REMAIN A
PRIME AREA FOR CRITICAL FIRE WEATHER CONDITIONS TO DEVELOP THIS
AFTERNOON AS THE DRYLINE SNEAKS INTO THE PANHANDLES. AS A RESULT
WILL LEAVE THE RED FLAG IN PLACE AND UNMODIFIED. FOR THE EASTERN
PANHANDLES THERE REMAINS A STRONG TO SEVERE STORM POTENTIAL THIS
AFTERNOON INTO THE OVERNIGHT HOURS. TTU WRF AND RUC HRRR SOLUTIONS
SHOW ISOLATED CONVECTION INITIATING ALONG AND EAST OF A VEGA TO
GUYMON LINE. RUC BUFR SOUNDINGS SHOW A WEAK CAP INHIBITING
INITIATION OF THESE STORMS UNTIL 6-7PM THIS EVENING. SHOULD THESE
STORMS FORM THEY WOULD BE ABLE TO TAP INTO ELEVATED INSTABILITY IN
THE RANGE OF 1000-1500 J/KG. DEEP LAYER SHEAR IN THE AREA OF LIKELY
INITIATION IS 25 TO 35 KT WITH A SLIGHT VEERING PATTERN. GIVEN
THE DEEP DRY LAYER BENEATH THE EXPECTED STORM BASES DAMAGING WINDS
OF 65 TO 70 MPH WOULD BE THE PRIMARY HAZARD BUT A HAIL THREAT CAN
NOT BE RULED OUT. ALL OF THIS IS ASSUMING THE WEAK CAP CAN BE
OVERCOME TO ALLOW STORMS TO DEVELOP. ANY STORMS THAT MAY DEVELOP
SHOULD DIMINISH BY 2 AM MONDAY MORNING.
DURING THE DAY MONDAY...THE DRYLINE WILL RACE ACROSS THE PANHANDLES
AND INTO WESTERN OKLAHOMA. THIS WILL PLACE THE VAST MAJORITY OF THE
PANHANDLES UNDER EXTREMELY DRY CONDITIONS WHICH COULD LEAD TO THE
RAPID SPREAD OF FIRE. WITH THAT BEING SAID RECENT RAINS PLUS ANY
ADDITIONAL RAIN WE GET TONIGHT WILL HELP TO MITIGATE SOME OF THIS
POTENTIAL. HAVE DECIDED TO NOT CARRY HEADLINES FOR MONDAY DUE TO THE
UNCERTAINTY OF PRECIP AMOUNTS AND COVERAGE FROM ANY STORMS
TONIGHT...BUT IF NO PRECIPITATION OCCURS A RED FLAG WARNING MAY BE
NEEDED FOR THE SIZABLE CHUNK OF THE AREA.
MODELS HAVE COME INTO A DECENT AGREEMENT FOR THE MID WEEK SYSTEM
WITH THE ECMWF LAGGING BEHIND THE OTHER MODELS SLIGHTLY. ALSO OF
NOTE HAS BEEN A SLIGHT INCREASE IN SPEED OF THE SYSTEM PLACING
BETTER PRECIP CHANCES ON TUESDAY AND CAUSING PRECIP CHANCES TO OCCUR
EARLIER IN THE DAY ON WEDNESDAY.
TUESDAY WILL BE A MIX OF FIRE WEATHER CONCERNS ACROSS THE WEST AND
ISOLATED SEVERE WEATHER CONCERNS ACROSS THE SOUTHEAST. THE POSITION
OF THE DRYLINE WILL BE THE MAJOR DETERMINING FACTOR AS TO WHO GETS
WHAT. FOR NOW HAVE GONE WITH A SPLIT OF THE GFS AND NAM ON DRYLINE
PLACEMENT WHICH ENDS UP BEING ROUGHLY ALONG A GUYMON TO CLAUDE LINE.
LOCATIONS WEST OF THIS LINE WILL HAVE A BETTER CHANCE FOR SEEING
ELEVATED TO NEAR CRITICAL FIRE WEATHER CONDITIONS...AND LOCATION
EAST OF THIS LINE WILL HAVE THE BETTER CHANCE OF SEEING
PRECIPITATION. LOOKING AT THE SYNOPTIC SCALE...A SHORTWAVE IS PROGGED TO
ROTATE AROUND THE BASE OF THE MAIN UPPER LEVEL TROUGH. THIS SYNOPTIC
LIFT COUPLED WITH CONVERGENCE ALONG THE DRYLINE COULD BE ENOUGH TO
INITIATE STORMS DURING THE AFTERNOON HOURS OF TUESDAY. DEEP LAYER
SHEAR FOR THIS TIME RANGES FROM 20 TO 35 KT AND INSTABILITY VALUES
RANGE FROM 1500 TO 2500 J/KG. STRONG TO SEVERE STORMS CAN NOT BE
RULED OUT AT THIS TIME WITH LARGE HAIL AND DAMAGING WINDS BEING THE
PRIMARY THREATS.
WEDNESDAY THE MAIN UPPER LEVEL TROUGH LOOKS TO TAKE A NEUTRAL TO
SLIGHTLY NEGATIVE TILT AS IT APPROACHES THE PANHANDLES. INSTABILITY
VALUES LOOK TO HAVE LOWERED SLIGHT WHICH COULD ALSO MEAN THAT THE
SEVERE THREAT MAY ALSO HAVE DIMINISHED SLIGHTLY. WITH THAT BEING
SAID CAPE VALUES OF 1000 TO 2000 J/KG AND DEEP LAYER SHEAR OF 35 TO
45 KT WILL KEEP AT LEAST THE CHANCE FOR STRONG STORMS AND A POSSIBLE
ISOLATED SEVERE STORM POSSIBLE. LARGE HAIL AND DAMAGING WINDS WILL
BE THE PRIMARY HAZARD.
THURSDAY THE UPPER FLOW BECOMES MORE ZONAL TO KEEP THAT AREA DRY AND
A WEAK COLD FRONT WILL DROP INTO THE PANHANDLES FRIDAY. CONDITIONS
LOOK TO REMAIN DRY GOING INTO THE WEEKEND.
&&
.FIRE WEATHER...
CRITICAL FIRE WEATHER CONDITIONS ARE STILL EXPECTED TO DEVELOP
ACROSS THE NORTHWESTERN TEXAS PANHANDLE AND WESTERN OKLAHOMA
PANHANDLE THIS AFTERNOON. OVERNIGHT THE DRYLINE WILL RETREAT AND
ALLOW RELATIVE HUMIDITIES TO RECOVER. HOWEVER...THE NORTHWESTERN
TEXAS AND WESTERN OKLAHOMA PANHANDLE MAY ONLY RECOVER SLIGHTLY WITH
MAXIMUM RELATIVE HUMIDITIES OF 30 TO 40 PERCENT.
ELEVATED TO NEAR CRITICAL FIRE WEATHER CONDITIONS WILL BE LIKELY ON
MONDAY FOR MUCH OF THE PANHANDLES AS RELATIVE HUMIDITIES DROP INTO
THE TEENS AND SINGLE DIGITS WITH SOUTHWEST 20 FOOT WINDS OF 20 TO 25
MPH WITH HIGHER GUSTS. THE RECENT RAINFALL ACROSS THE SOUTHERN TEXAS
PANHANDLE AND ANY ADDITIONAL RAINFALL TONIGHT WILL PROVIDE SOME
LIMITATIONS ON FIRE POTENTIAL...TO GO ALONG WITH LOW FUEL LOADING
DUE TO THE ONGOING DROUGHT. FOR NOW WILL KEEP HEADLINES SILENT FOR
THIS TIME PERIOD.
ELEVATED TO NEAR CRITICAL FIRE WEATHER CONDITIONS MAY DEVELOP ACROSS
THE WESTERN PANHANDLES TUESDAY AFTERNOON AS RELATIVE HUMIDITIES DROP
INTO THE SINGLE DIGITS ONCE AGAIN BEHIND THE DRYLINE AND 20 FOOT
SOUTHERLY WINDS OF 15 TO 25 MPH WINDS. HOWEVER PRECIP CHANCES WILL
BEGIN TO ENTER THE PANHANDLES DURING THE LATE AFTERNOON AND EVENING
HOURS WHICH COULD BRING AN EARLY END TO FIRE WEATHER CONDITIONS.
FIRE WEATHER CONDITIONS FROM WEDNESDAY THROUGH THE REST OF THE WORK
WEEK WILL BE HIGHLY DEPENDENT ON PRECIPITATION EXPECTED TUESDAY AND
WEDNESDAY. SHOULD THE WESTERN PANHANDLES GET LITTLE TO NO
PRECIPITATION TUESDAY AND WEDNESDAY...THEN ELEVATED TO NEAR CRITICAL
FIRE WEATHER CONDITIONS COULD BE POSSIBLE TUESDAY AFTERNOON...AND
ELEVATED FIRE WEATHER CONDITIONS THURSDAY AND FRIDAY.
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...RED FLAG WARNING UNTIL 9 PM CDT THIS EVENING FOR THE FOLLOWING
ZONES: DALLAM...HARTLEY...MOORE...SHERMAN.
OK...RED FLAG WARNING UNTIL 9 PM CDT THIS EVENING FOR THE FOLLOWING
ZONES: CIMARRON...TEXAS.
&&
$$
15/14
AREA FORECAST DISCUSSION...UPDATED
NWS LUBBOCK TX
100 PM CDT SUN MAY 26 2013
.UPDATE...
18Z AVIATION DISCUSSION BELOW. MINOR UPDATE TO PREVIOUS FORECAST
TO REFLECT INCREASING CHANCES OF ISOLATED DRYLINE STORMS BY LATER
THIS AFTERNOON. REGIONAL SURFACE OBSERVATIONS INDICATE TWO AREAS
OF INTEREST FOR POSSIBLE INITIATION ALONG THE DEVELOPING DRYLINE...
THE FIRST AREA IS IN THE SOUTH-CENTRAL TX PANHANDLE AHEAD OF A
DEVELOPING DRYLINE BULGE WHILE A SECOND MORE SUBTLE ZONE OF
INTEREST IS EMERGING FARTHER SOUTH IN THE PERMIAN BASIN WHERE LL
CONVERGENCE IS IMPROVING. RECENT BACKING OF WINDS AT SNYDER AND
VEERING OF WINDS FARTHER WEST AT ANDREWS SUGGEST THE 15Z HRRR MAY
BE CREDIBLE WITH INITIATION HERE BEFORE EXPANDING NORTH ALONG THE
DRYLINE. OPTED TO EXPAND ISOLATED SEVERE TSTORM MENTION OFF THE
CAPROCK AS ANY STORMS JUST SOUTH OF THE CWA COULD CERTAINLY
THREATEN OUR LOW ROLLING PLAINS GIVEN MORE EASTERLY STORM MOTIONS
HERE VERSUS SELY STORM MOTIONS AND HIGHER PROBS OF SUPERCELLS
FARTHER NORTH. LACK OF CU THUS FAR IS AN INDICATION THAT MOISTURE
IS DEEPER THEREBY LIMITING GREATER MIXING HEIGHTS...BUT WITH TIME
WE EXPECT THIS TO CHANGE NEAR THE DRYLINE WHERE DEWPOINTS SHOULD
FALL INTO THE 20S AND 30S AND PROMOTE A DEEPENING DRYLINE
CIRCULATION. REMAINDER OF FORECAST REMAINS ON TRACK.
&&
.AVIATION...
OUTSIDE OF ISO +TSRAGR EXPECTED TO DEVELOP AROUND 22Z ALONG A
DRYLINE NEAR I-27...VFR CONDS TO PREVAIL WITH SOUTHERLY WINDS OF
15-20 KNOTS. EXPECTED LOW COVERAGE OF STORMS PRECLUDES MENTION IN
TAFS...BUT WILL AMMEND IF CONDITIONS WARRANT. BEST CHANCE OF LOW
STRATUS BY DAYBREAK MEMORIAL DAY SHOULD RESIDE EAST OF THE
TERMINALS.
&&
.PRELIMINARY POINT TEMPS/POPS...
FRIONA 94 61 95 62 95 / 10 10 10 10 10
TULIA 92 64 96 65 92 / 20 20 10 10 30
PLAINVIEW 93 65 96 65 92 / 20 20 10 10 30
LEVELLAND 96 68 97 65 93 / 20 20 10 10 20
LUBBOCK 95 68 98 66 92 / 20 20 20 10 30
DENVER CITY 97 67 97 65 93 / 10 10 10 10 20
BROWNFIELD 97 69 98 65 93 / 20 20 20 10 20
CHILDRESS 95 69 97 69 92 / 20 20 20 20 30
SPUR 92 68 97 68 92 / 20 20 20 20 20
ASPERMONT 94 69 95 69 94 / 20 20 10 20 20
&&
.LUB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
93/99/93
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
120 PM EDT SUN MAY 26 2013
.SYNOPSIS...
WEAK HIGH PRESSURE WILL DRIFT ACROSS THE REGION THROUGH THE FIRST
HALF OF THE WEEK AS THE DEEP...COLD UPPER LOW OVER NEW ENGLAND
LIFTS SLOWLY AWAY FROM THE REGION. A WARM FRONT WILL MOVE
NORTHWARD THROUGH THE REGION TUESDAY...ALLOWING BERMUDA HIGH
PRESSURE TO DOMINATE FOR THE LATER HALF OF THE WEEK WITH
INCREASINGLY WARM...HUMID CONDITIONS AND INCREASING CHANCES FOR
AFTERNOON SHOWERS AND THUNDERSTORMS.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 905 AM EDT SUNDAY...
WATER VAPOR SATELLITE IMAGERY INDICATES WEAK A WEAK UPPER LEVEL
DISTURBANCE PUSHING SOUTH THROUGH SW VA/NW NC AND SHOULD EXIT BY
15Z. A FEW RETURNS WERE NOTED ON RADAR IN THE NC FOOTHILLS AND A
SOCIAL MEDIA POST CONFIRMS A FEW SPRINKLES WERE FALLING UNDER
THESE ECHOES. PER THE 12Z GSO SOUNDING...THIS VERY LIGHT PRECIP
FALLING UNDER A MID LEVEL 6K FOOT DEPTH MOIST LAYER.
THEREFORE ADDED A MENTION OF SPRINKLES TO THIS AREA THROUGH UNTIL
15Z...WHEN THE 11Z HRRR ENDS THE PRECIP IN OUR FORECAST AREA.
OTHERWISE...PUSHED UP HIGH TEMPS A COUPLE OF DEGREES FOR TODAY AS
WE ARE STARTING MUCH WARMER THAN THIS TIME YESTERDAY AND EXPECT
CLEARING SKIES WITH THE DEPARTING UPPER LEVEL WAVE. THE WARMER
06Z GFS MOS HAD A BETTER HANDLE ON THE PROJECTED 12Z TEMPS VERSUS
THE 06Z NAM MOS...AND ADJUSTED FORECAST HIGHS TOWARD ITS FORECAST
HIGHS FOR TODAY.
THE NEXT NW FLOW DISTURBANCE MOVES TOWARD THE REGION OVERNIGHT
TONIGHT INTO EARLY MONDAY. SFC MOISTURE RECOVERY REMAINS SCANT AS
DEWPOINTS CREEP INTO THE 40S. THUS...STILL DO NOT REALLY EXPECT
MUCH PCPN WITH THIS FEATURE. HOWEVER...THIS DISTURBANCE COMES ON
THE THRESHOLD OF A SIGNIFICANT RISE IN 850MB TEMPS INTO THE +12C
TO +16C RANGE BY MON AFTERNOON...SO WITH STRONGER WAA ADVECTION
AND THE OVERALL BAROCLINIC ZONE SHIFTING MORE INTO THE REGION FROM
THE SOUTH...EXPECT BETTER CHCS FOR -SHRA WITH THIS SYSTEM THAN
WITH THIS MORNINGS. THROUGH 12Z MON...THE ATMOSPHERE WILL REMAIN
ENTIRELY TOO STABLE AND COOL FOR ANY -TSRA...HOWEVER.
&&
.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
AS OF 430 AM EDT SUNDAY...
FOR MONDAY...WINDS WILL BECOME MORE SOUTHERLY AS HIGH PRESSURE
SHIFTS OFF THE ATLANTIC COAST...WHILE A WARM FRONT MOVES NORTHWARD
ALONG THE OHIO RIVER VALLEY INTO THE CENTRAL APPALACHIAN CHAIN. WITH
STRONGER AFTERNOON HEATING THAN SEEN DURING THE WEEKEND COUPLED WITH
INSTABILITY ASSOCIATED WITH THE FRONT CROSSING OUR AREA...WILL SEE A
CHANCE FOR SHOWERS AND A FEW THUNDERSTORMS DURING THE AFTERNOON AND
EVENING. MODELS ARE ALSO HINTING AT A DISTURBANCE RIDING ALONG THE
FRONT MONDAY NIGHT/EARLY TUESDAY MORNING THAT MAY BRING SPOTTY
SHOWERS NORTHWEST TO SOUTHEAST ACROSS THE AREA...LOOKING LIKE
REMNANTS OF STRONGER ACTIVITY OCCURRING WEST OF THE AREA EARLIER IN
THE EVENING. UNSURE HOW MUCH PRECIPITATION WILL BE LEFT AS THIS
SYSTEM MOVES ACROSS THE MORE STABLE ENVIRONMENT OF OUR AREA...SO
WILL STICK WITH SLIGHT CHANCE WORDING IN THE FORECAST FOR NOW.
BY TUESDAY...THE WARM FRONT WILL HAVE LIFTED NORTH OF OUR AREA...AND
WE WILL ENTER A WEATHER PATTERN OF STRONGER SOUTHWESTERLY WINDFLOW
THAT IS TYPICAL OF WHAT WE SEE DURING THE SUMMER MONTHS. AS SUCH...
LOOKING FOR A ROUND OF AFTERNOON SHOWERS AND THUNDERSTORMS TRIGGERED
BY DAYTIME HEATING...MAINLY ACROSS THE MOUNTAIN RIDGES TO START AND
THEN SPREADING TO THE PIEDMONTS DURING LATE AFTERNOON. COVERAGE WILL
REMAIN SPOTTY AT BEST...AND CONVECTION WILL DIMINISH QUICKLY AFTER
SUNSET.
MORE SHOWER AND THUNDERSTORM ACTIVITY CAN BE EXPECTED FOR
WEDNESDAY...ALTHOUGH COVERAGE IS EXPECTED TO BE A LITTLE MORE
ISOLATED AS UPPER LEVEL RIDGING INCREASES ACROSS THE SOUTHEAST
STATES...ADDING SLIGHTLY MORE STABILITY TO THE ATMOSPHERE.
THE GRADUAL BUILD IN UPPER LEVEL RIDGING THROUGH THE EARLY HALF OF
THE WEEK WILL ALSO LEAD TO WARMING TEMPERATURES...WITH AFTERNOON
HIGHS BY WEDNESDAY RANGING FROM UPPER 70S/LOW 80S ACROSS THE
MOUNTAINS...TO THE MID 80S ACROSS THE PIEDMONTS. LOWS WILL BE IN THE
UPPER 50S TO LOW 60S.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 330 PM EDT SATURDAY...
HEAT WAVE POSSIBLE THROUGH THE END OF NEXT WEEK AS A 590DM UPPER
RIDGE CLOSES OFF OVER THE MIDDLE ATLANTIC IN RESPONSE TO A REX BLOCK
AND CLOSED LOW OVER THE CONTINENTAL DIVIDE. POPS DECREASE THROUGH
THE WEEK WITH SINKING MOTION AND THE PROFILE BECOMING TOO DRY TO
SUPPORT ANYTHING MORE THAN THE MOST ISOLATED THUNDERSTORM ALONG
THE HIGHEST PEAKS BY END WEEK. 90F LOOKS POSSIBLE IN MOST OF THE
CITIES PERHAPS AS EARLY AS THURSDAY. UPPER AIR PATTERN MAY FLATTEN
BY THE END OF NEXT WEEKEND.
&&
.AVIATION /17Z SUNDAY THROUGH THURSDAY/...
AS OF 120 PM EDT SUNDAY...
FOR THE 18Z TAF VALID PERIOD...VFR CONDITIONS ARE EXPECTED.
OVERNIGHT...A WEAK UPPER LEVEL DISTURBANCE WILL MOVE THROUGH THE
THE AREA ON THE BACK SIDE OF A DEPARTING DEEP NORTHEAST U.S. UPPER
LOW WHICH WILL BRING SOME HIGH/MID CLOUDS AGAIN LATE TONIGHT.
ON MONDAY...A WARM FRONT WILL LIFT NORTH THROUGH OUR AREA BRINGING
AN INCREASE IN MOISTURE AND UNSTABLE AIR. THIS WILL RESULT IN A
BETTER CHANCE FOR AFTERNOON THUNDERSTORMS IN THE MOUNTAINS. SINCE
MOST STORM ARE EXPECTED TO DEVELOP 18Z OR LATER MONDAY...NO PRECIP
WAS ADDED TO THE TAFS. WINDS WILL BE LIGHT MONDAY...BUT VEER EARLY
TO THE SOUTHEAST THEN SOUTHWEST.
EXTENDED AVIATION DISCUSSION...MOISTURE INCREASES LATE MON-TUE AS
THE SFC HIGH MOVES EAST AND THE UPPER RIDGE STRENGTHENS OVER THE
MISSISSIPPI VALLEY. A WEAK WARM FRONT/BAROCLINIC ZONE WILL SLIDE
NE ACROSS THE REGION EARLY MON- TUE AHEAD OF THE VERY WARM/MOIST
AIR THAT WILL BE PUSHING IN FROM THE SW. THIS WILL LEAD TO A
SLIGHTLY BETTER SHOT AT SEEING A FEW SHRA/TSRA THROUGH TUESDAY
WITH AT LEAST OROGRAPHIC DRIVEN CONVECTION FOR MID WEEK. PATCHY
LATE NIGHT FOG ALSO LIKELY DURING THE OVERNIGHTS ESPCLY VALLEYS
AND WHERE AFTERNOON/EVENING RAINFALL OCCURS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...RAB
NEAR TERM...RAB
SHORT TERM...PH
LONG TERM...KM
AVIATION...PH
AREA FORECAST DISCUSSION
NWS SPOKANE WA
1244 PM PDT Sun May 26 2013
.SYNOPSIS...
The Pacific Northwest will remain under the influence of a
persistent area of low pressure through the week. Showers will be
of the scattered variety today and tomorrow. The arrival of a moist
frontal system on Tuesday will bring a better chance for widespread
light rain for eastern Washington and northern Idaho. This low
pressure pattern may break by the end of the week allowing
temperatures to warm closer to average by next weekend.
&&
.DISCUSSION...
Minor update to increase high temperatures for the Moses Lake area
and Upper Columbia Basin. Sufficient breaks in the clouds
especially in Moses Lake allowed high temperatures to exceed
forecast values. Radar shows increasing showers around the Tri-
Cities area, Blue Mountains, and Camas Prairie early this
afternoon. As the wave over Oregon moves northeast the HRRR is
showing numerous showers through early this evening over the Blue
Mountains, Lewiston area, Camas Prairie, and Central Panhandle
Mountains with isolated thunderstorms also possible. The
Washington Palouse looks to be on the northwest edge of the best
shower activity. A secondary focus of showers will be along the
East Slopes of the Cascades with Ellensburg and Wenatchee both
reporting a rain shower at noon. Elsewhere isolated to scattered
coverage of showers is still expected late in the afternoon into
this evening. JW
&&
.AVIATION...
18Z TAFS: Scattered showers will increase today especially near the
Cascades and around KPUW/KLWS as a low pressure system tracks across
Oregon. Isolated thunderstorms are also possible at KPUW/KLWS but
with low probability of storms moving over these locations just kept
a CB group. CIGS with these showers today should remain VFR.
Showers will decrease after 03z with the loss of daytime heating.
Between 12-18z Monday, boundary layer moisture increases along the
KGEG-KSFF-KCOE with low level upslope such that MVFR stratus may
develop. The NAM model shows this to be a marginal case for a
broken MVFR CIG...but this can not be ruled out. JW
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 67 47 65 47 63 46 / 30 20 10 30 50 40
Coeur d`Alene 68 46 67 44 62 44 / 30 30 20 30 50 50
Pullman 65 43 65 45 62 44 / 50 50 20 40 50 40
Lewiston 69 49 72 51 67 49 / 50 50 10 40 50 30
Colville 73 46 70 44 67 45 / 20 20 20 20 50 50
Sandpoint 67 44 66 42 61 42 / 20 30 30 20 60 60
Kellogg 67 46 63 45 58 45 / 40 50 30 30 60 50
Moses Lake 72 48 69 49 71 47 / 40 20 10 20 30 20
Wenatchee 63 50 66 51 68 49 / 50 30 20 20 30 20
Omak 67 44 69 46 69 45 / 30 20 10 30 50 40
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS SPOKANE WA
1032 AM PDT Sun May 26 2013
.SYNOPSIS...
The Pacific Northwest will remain under the influence of a
persistent area of low pressure through the week. Showers will be
of the scattered variety today and tomorrow. The arrival of a moist
frontal system on Tuesday will bring a better chance for widespread
light rain for eastern Washington and northern Idaho. This low
pressure pattern may break by the end of the week allowing
temperatures to warm closer to average by next weekend.
&&
.DISCUSSION...
Update: Satellite imagery as of 8 am this morning showed two lows
of interest...one over Vancouver Island and the other moving into
western Oregon. The low over Vancouver Island is expected to be
nearly stationary today...while the low over western Oregon tracks
east into central Oregon this afternoon. The placement of these
two features will result in the bulk of the showers today over the
Cascades during the late morning and afternoon, and from the Blue
Mountains extending northeast towards the Central Panhandle
Mountains in the afternoon. Precipitation chances in these areas
have been adjusted upward slightly based on latest radar trends
and the HRRR showing quite a bit of shower activity moving into
these areas. Models still show potential for isolated
thunderstorms this afternoon mainly over the Blues, Lewiston area,
Palouse, and Central Panhandle Mountains.
Also extensive cloud cover over North Central Washington this
morning and showers expected to move into this area will keep high
temperatures down and forecast values were adjusted accordingly
for places like Wenatchee, Chelan, Winthrop, and Omak. Elsewhere
across the region showers will be more isolated to scattered in
nature with the main adjustment to lower sky cover this morning in
the Sandpoint and Kellogg areas where more extensive cloud cover
will hold off til late morning/early afternoon. JW
&&
.AVIATION...
18Z TAFS: Scattered showers will increase today especially near the
Cascades and around KPUW/KLWS as a low pressure system tracks across
Oregon. Isolated thunderstorms are also possible at KPUW/KLWS but
with low probability of storms moving over these locations just kept
a CB group. CIGS with these showers today should remain VFR.
Showers will decrease after 03z with the loss of daytime heating.
Between 12-18z Monday, boundary layer moisture increases along the
KGEG-KSFF-KCOE with low level upslope such that MVFR stratus may
develop. The NAM model shows this to be a marginal case for a
broken MVFR CIG...but this can not be ruled out. JW
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 67 47 66 48 64 47 / 30 20 30 30 50 50
Coeur d`Alene 68 46 65 45 63 45 / 30 40 40 20 50 60
Pullman 64 45 66 47 63 45 / 50 40 20 40 50 50
Lewiston 69 50 73 52 67 50 / 50 40 10 30 50 50
Colville 73 46 70 45 68 46 / 20 20 50 20 50 50
Sandpoint 67 44 64 43 62 43 / 20 40 50 20 50 70
Kellogg 65 46 62 47 59 46 / 40 50 50 20 60 70
Moses Lake 66 49 72 50 72 48 / 40 20 10 30 30 30
Wenatchee 63 50 69 50 70 50 / 50 10 10 30 40 30
Omak 67 46 71 47 69 46 / 30 10 20 30 40 40
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1246 PM CDT SUN MAY 26 2013
.UPDATE...
ISSUED AT 949 AM CDT SUN MAY 26 2013
A MESOSCALE CONVECTIVE COMPLEX CONTINUES TO MOVE EAST SOUTHEAST
ACROSS SOUTHEAST MINNESOTA AND NORTHEAST IOWA THIS MORNING. THE
HRRR SEEMS TO HAVE A FAIRLY GOOD HANDLE ON THIS SYSTEM...SO USED
IT TO ADD SOME MORE TIMING TO THE HOURLY PRECIPITATION CHANCES FOR
THE REST OF THIS MORNING AND THE AFTERNOON. LIKE YESTERDAY...THE
KARX RADAR IS OVERESTIMATING PRECIPITATION RATES BY 200 TO 300
PERCENT IN BOTH THE LEGACY AND DUAL POLE PRECIPITATION AMOUNT
PRODUCTS...SO CAUTION IS ADVISED WHEN USING THESE PRODUCTS. WHILE
OUR RADAR IS OVERESTIMATING...KDMX RADAR PRECIPITATION TOTAL
PRODUCTS DO LOOK REALISTIC. WITH THE COMPLEX MOVING A BIT FURTHER
NORTH THAN YESTERDAY...EXPECT THE CLOUDS AND PRECIPITATION TO KEEP
THE HIGH TEMPERATURES MAINLY IN THE 50S ALONG ALONG AND SOUTH OF
THE INTERSTATE 90 CORRIDOR.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 230 AM CDT SUN MAY 26 2013
CONVECTION HAS LIT UP DURING THE OVERNIGHT HOURS IN RESPONSE TO THE
SURFACE/850 MB WARM FRONT AND THE IMPINGEMENT OF THE LOW LEVEL
JET/MOISTURE TRANSPORT. HRRR DOING A DECENT JOB WITH THE CURRENT
CONVECTION...AND WILL NUDGE THIS TO LOCATIONS WEST OF THE
MISSISSIPPI RIVER BETWEEN 12-15Z. THIS MATCHES UP WITH THE SPCWRF.
ARWWRF/NAM12 MEANWHILE DECREASE THE AREAL COVERAGE AS IT MOVES EAST
THIS MORNING...BUT STILL HANG ON TO ISOLD/SCT SHOWERS INTO THE
AFTERNOON.
EXPECTATION IS FOR ANOTHER THUNDERSTORM COMPLEX TO DEVELOP OVER THE
CENTRAL PLAINS/WESTERN IA LATER TONIGHT...WITH AN EAST/NORTHEAST
PUSH INTO THE FORECAST AREA.
.LONG TERM...(MONDAY THROUGH SUNDAY)
ISSUED AT 230 AM CDT SUN MAY 26 2013
PRIMARY WEATHER MAKERS FOR THE NEXT FEW DAYS REMAIN UNCHANGED...A
WARM FRONT...POSITION/STRENGTH OF THE LOW LEVEL JET/MOISTURE
TRANSPORT...AND CONVECTION INDUCED MCVS/ENHANCED SHORTWAVE TROUGHS.
WHERE THESE LIE...MOVE...AND MOST IMPORTANTLY...INTERACT...WILL BE
WHERE THE GREATEST THREAT FOR SHOWERS AND THUNDERSTORMS WILL BE.
NAM/GFS/ECMWF HAVE BEEN IN PRETTY GOOD AGREEMENT WITH ADVANCING THE
WARM FRONT...CURRENTLY LYING WEST-EAST ACROSS NORTHERN MO/SOUTHERN
ILL...NORTHWARD ON MONDAY...ENDING UP ACROSS NORTHERN WI LATE WED
NIGHT. THE 850 MB MOISTURE TRANSPORT NOSES INTO/ACROSS THE FRONT ON
MONDAY...BULLSEYEING THE FORECAST AREA. A 500 MB MCV/SHORTWAVE
TROUGH WILL SPIN ACROSS THE PLAINS AND OVER THE UPPER MISSISSIPPI BY
00Z TUES...AIDING SHOWER/STORM DEVELOPMENT.
TUE PROVIDES A SIMILAR SCENARIO WITH A SHORTWAVE TROUGH MOVING IN
FROM THE WEST...BEING ENHANCED FROM CONVECTION SPAWNED FROM THE
MOISTURE TRANSPORT/WARM FRONT INTERACTIONS OVER IA/SOUTHERN MN. THE
FIRST PART OF TUES LOOKS WET AS THE CONVECTIVE COMPLEX FROM LATE
MONDAY MOVES THROUGH. THE LATER 1/2 SHOULD SEE A BREAK FROM
WIDESPREAD RAIN...WITH YET ANOTHER COMPLEX THEN MOVING IN OVERNIGHT
AS CONVECTION SPARKS TO THE WEST.
WED HAS THE WARM FRONT MOVING NORTH OF THE FORECAST AREA...BUT HOW
QUICKLY THIS OCCURS WILL DEPEND ON WHERE THAT EXPECTED RAIN AREA
IS...AND HOW SOON IT EXITS. THIS WOULD SHIFT THE MAIN PCPN FOCUS
TO THE NORTH - ALTHOUGH ONLY BRIEFLY. A SHORT DRYING PERIOD COULD
SEE THE THREAT FOR SHOWERS/STORMS RETURN BY THU
AFTERNOON...CONTINUING INTO FRIDAY. A STRONG PUSH OF LOW LEVEL
MOISTURE WILL REMAIN THE MAIN FIRING MECHANISM...WITH SOME HELP FROM
ENERGY MOVING OUT OF THE UPPER LEVEL TROUGH SITTING TO THE WEST.
DIFFERENCES CONTINUE TO CROP UP BETWEEN THE GFS/EC IN HOW THEY WANT
TO HANDLE THE EVENTUALLY BREAK DOWN/EXIT OF THE TROUGH TO THE WEST
IN THIS RATHER STAGNANT PATTERN. THE GFS REMAINS THE MORE
PROGRESSIVE OF THE SOLUTIONS...WHILE THE EC CONTINUES TO SUGGEST A
CLOSED LOW WOULD DEVELOP...AND SLOW DOWN ITS ALREADY LETHARGIC
STROLL EAST. OBVIOUS IMPLICATIONS IN RAIN CHANCES FOR THE WEEKEND.
WITH CONFIDENCE NOT HIGH IN EITHER OUTCOME...WILL STAY THE COURSE
WITH THE CONSENSUS SOLUTION FOR THE DETAILS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1246 PM CDT SUN MAY 26 2013
A MESOSCALE CONVECTIVE COMPLEX WILL CONTINUE TO MOVE EAST THROUGH
SOUTHWEST WISCONSIN EARLY THIS AFTERNOON. KLSE WILL BE ON THE
NORTHERN EDGE OF THIS SYSTEM...THUS...NOT EXPECTING ANY VISIBILITY
RESTRICTIONS. BEHIND THIS SYSTEM...THE CLOUDS WILL DESCEND DOWN TO
4K FEET. MEANWHILE AT KRST...THE CEILINGS WILL LIKELY REMAIN IFR
THROUGH 27.18Z.
ANOTHER SHORT WAVE TROUGH...CURRENTLY MOVING OUT OUR SOUTH DAKOTA
AND NEBRASKA WILL BRING ANOTHER ROUND OF PRECIPITATION TO THE TAF SITES
LATE THIS AFTERNOON AND EARLY EVENING. THE SHOWERS SHOULD ARRIVE
KRST AROUND 26.21Z AND AT KLSE AROUND 26.23Z. ONCE THE
PRECIPITATION MOVES INTO THE AREA...IT SHOULD LAST 2 TO 3 HOURS.
BEHIND THIS WAVE...THE CEILINGS WILL BECOME MVFR AT KLSE AND
REMAIN THERE THROUGH THE REMAINDER OF THE TAF PERIOD.
AFTER MIDNIGHT TONIGHT...YET ANOTHER MESOSCALE CONVECTIVE COMPLEX
WILL MOVE EAST INTO THE AREA. IT APPEARS THAT THIS SYSTEM WILL
MOVE INTO KRST AROUND 27.07Z AND KLSE AROUND 27.09Z. UNSURE OF THE
ENDING TIME...SO JUST LEFT THE SHOWERS GO THROUGH THE REMAINDER OF
THE TIME PERIOD.
WITH THE INSTABILITIES INCREASING ACROSS THE AREA AFTER MIDNIGHT
TONIGHT...THOUGHT ABOUT ADDING THUNDER TO THE TAF SITES...BUT WAS
TOO UNCERTAIN TO PIN DOWN A TIMING...SO HELD OFF FOR NOW.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...BOYNE
SHORT TERM...RIECK
LONG TERM....RIECK
AVIATION...BOYNE