Forecast Discussions mentioning any of
"HRRR" "RR" "RUC13" "RUC" received at GSD on 04/16/12
AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
1006 PM CDT SUN APR 15 2012
.UPDATE...
HAVE UPDATED THE MAJORITY OF FORECAST THROUGH THE OVERNIGHT HOURS
AS SEVERE THREAT CONTINUES TO WIND DOWN THIS EVENING. ONLY
MINIMAL WARNINGS WERE NEEDED THIS EVENING AS TORNADIC STORMS WERE
NEVER REALLY ABLE TO GET GOING DUE TO THE LACK OF LOW LEVEL
INSTABILITY WITH ONLY A FEW BOW ECHO STRUCTURES BEING ABLE TO GET
ESTABLISHED.
WHAT THREAT DOES REMAIN FOR THE STATE HAS PUSHED OFF TO THE EAST
AND NORTHEAST AND THE TORNADO WATCH HAS BEEN DISCONTINUED FOR THE
LITTLE ROCK COUNTY WARNING AREA. HOWEVER...SEVERAL MORE HOURS OF
SHOWERS WITH EMBEDDED THUNDER WILL PERSIST BEFORE ENDING FROM WEST
TO EAST OVERNIGHT.
FORECAST UPDATED TO ADJUST PRECIPITATION CHANCES BASED ON RADAR
TRENDS AND TEMPERATURES AS MANY AREAS ALREADY CLOSE TO OVERNIGHT
LOWS. ALL PRODUCTS OUT.
&&
.PREV DISCUSSION... /ISSUED 747 PM CDT SUN APR 15 2012/
UPDATE...
HAVE UPDATED 1ST AND 2ND PERIOD GRIDS TO REFLECT RECENT RADAR AND
SFC OBSERVATION TRENDS. MAIN BAND OF SHOWERS AND EMBEDDED
THUNDERSTORMS STRETCHES FROM MENA UP THROUGH CLARKSVILLE AND
HARRISON IN THE WEST...AND EL DORADO TO BATESVILLE IN THE EAST.
RAPID REFRESH RUC AS WELL AS OTHER HIGH RESOLUTION MODELS
CONTINUE TO INDICATE THE BACK EDGE OF THIS LINE WILL CLEAR A
HARRISON-MENA LINE BY ROUGHLY 10 PM...A BATESVILLE-LITTLE ROCK-
CAMDEN LINE AROUND 1 AM...AND FINALLY MONTICELLO SHORTLY BEFORE
DAY BREAK MONDAY MORNING. HAVE ADJUSTED POP GRIDS ACCORDINGLY.
THE THREAT THREAT FOR TORNADOES...DAMAGING WINDS AND LARGE HAIL
SEEMS TO BE QUICKLY DIMINISHING GIVEN RADAR TRENDS AND INSTABILITY
INDICES. HAVE ALREADY TRIMMED BACK SOME WESTERN COUNTIES FROM
TORNADO WATCH 179. WILL CONTINUE TO MONITOR RADAR TRENDS OVER THE
NEXT FEW HOURS...AND FURTHER TRIM COUNTIES WHEN/WHERE POSSIBLE.
OTHERWISE JUST TWEAKED TEMPS AND WINDS FOR THE OVERNIGHT HOURS.
ALL UPDATED PRODUCTS AND GRIDS ARE OUT.
PREV DISCUSSION... /ISSUED 615 PM CDT SUN APR 15 2012/
AVIATION...
THE 00Z TAFS WILL BE OUT SHORTLY.
PRIMARY CONCERNS FOR THIS TAF CYCLE WILL BE THUNDERSTORMS. LEADING
EDGE OF SQUALL LINE WAS LOCATED FROM JUST EAST OF ARKADELPHIA NE
THROUGH CONWAY AND UP THROUGH MOUNTAIN VIEW AS OF 2300Z. EXPECT
THIS LINE TO AFFECT KLIT BY RIGHT AT 00Z...KPBF BY 01-02Z...AND
KLLQ AROUND 02Z. WILL ADVERTISE PREVAILING -SHRA WITH VCTS AND
TEMPO TSRA AND MVFR CONDITIONS THROUGH ROUGHLY 04Z FOR ALL SITES
EXCEPT KHRO. BACK EDGE OF LINE IS APPROACHING KHRO AND SHOULD PUSH
EAST OF THERE BY 02Z- 03Z...EAST OF KLIT BY ROUGHLY 07Z AND
FINALLY EAST OF KLLQ BY 08Z- 09Z. AFTER LINE PUSHES THROUGH...A
QUICK RETURN TO VFR CONDITIONS SHOULD BE SEEN...WITH SKC 4-6HRS
AFTER LINE PUSHES THROUGH.
PREV DISCUSSION... /ISSUED 303 PM CDT SUN APR 15 2012/
SHORT TERM...TONIGHT THROUGH WEDNESDAY NIGHT
STORMS HAVING SOME DIFFICULTY INTENSIFYING IN WESTERN ARKANSAS
EARLY THIS AFTERNOON. INSTABILITY GRADUALLY INCREASING...AND
WOULD EXPECT PRECIPITATION TO CONGEAL INTO MORE OF A LINE AS
IT MOVES INTO CENTRAL/EASTERN SECTIONS OF THE STATE THIS EVENING.
SOME STORMS COULD BE SEVERE...WITH WIND DAMAGE THE MAIN CONCERN.
MAIN STORM SYSTEM WILL MOVE WELL TO THE NORTH ON MONDAY...AND THE
FRONT TRIGGERING THE PRECIPITATION WILL STALL FOR A TIME JUST
SOUTHEAST OF THE STATE. GIVEN THIS...ISOLATED TO SCATTERED SHOWERS
AND THUNDERSTORMS COULD LINGER SOUTHEAST OF LITTLE ROCK. OTHERWISE...
CLEARING WILL OCCUR FARTHER NORTH AND WEST...WITH SLIGHTLY
COOLER/DRIER AIR.
PRECIPITATION CHANCES WILL FINALLY COME TO AN END IN THE
SOUTHEAST MONDAY EVENING AS HIGH PRESSURE BUILDS INTO THE REGION
FROM THE PLAINS. THIS WILL KICK THE FRONT TOWARD THE SOUTHEAST
UNITED STATES.
THE REMAINDER OF THE PERIOD WILL FEATURE TRANQUIL CONDITIONS.
TEMPERATURES TUESDAY AND WEDNESDAY WILL BE MOSTLY ABOVE NORMAL.
LONG TERM...THURSDAY THROUGH SUNDAY
FORECAST WILL START OFF DRY AS NEARLY ZONAL FLOW WILL BE IN PLACE
ACROSS THE CENTRAL CONUS AT THE START OF THE LONG TERM.
HOWEVER...UPPER LEVEL TROUGH WILL EXIT THE ROCKIES BY
FRI...DEEPENING OVER THE PLAINS. THIS WILL PUSH A COLD FRONT SOUTH
ACROSS AR BY FRI EVENING. HAVE PRECIP CHANCES STARTING LATE THU
NIGHT ACROSS THE NW...THEN SPREADING SE DURING THE DAY ON FRI AS THE
FRONT TRAVERSES THE STATE. PRECIP CHANCES THEN DECREASE FROM NW TO
SE BY FRI NIGHT INTO SAT AS HIGH PRESSURE DIVES SE ACROSS THE PLAINS.
DRY CONDITIONS WILL THEN PERSIST THROUGH PRETTY MUCH THE REST OF THE
LONG TERM AS NW UPPER FLOW WILL BE DOMINANT ACROSS THE CENTRAL
CONUS.
&&
.PRELIMINARY POINT TEMPS/POPS...
BATESVILLE AR 54 72 49 74 / 90 10 10 0
CAMDEN AR 58 80 55 80 / 80 20 10 0
HARRISON AR 49 70 46 73 / 80 10 10 0
HOT SPRINGS AR 54 79 54 78 / 90 10 10 0
LITTLE ROCK AR 56 78 55 77 / 90 10 10 0
MONTICELLO AR 61 80 58 79 / 90 20 10 0
MOUNT IDA AR 53 77 48 77 / 90 10 10 0
MOUNTAIN HOME AR 50 73 46 75 / 90 10 10 0
NEWPORT AR 56 73 49 75 / 100 20 10 0
PINE BLUFF AR 59 78 56 78 / 90 20 10 0
RUSSELLVILLE AR 52 75 48 78 / 90 10 10 0
SEARCY AR 55 76 46 75 / 100 10 10 0
STUTTGART AR 58 77 53 76 / 90 20 10 0
&&
.LZK WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...56 / LONG TERM...64
AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
747 PM CDT SUN APR 15 2012
.UPDATE...
HAVE UPDATED 1ST AND 2ND PERIOD GRIDS TO REFLECT RECENT RADAR AND
SFC OBSERVATION TRENDS. MAIN BAND OF SHOWERS AND EMBEDDED
THUNDERSTORMS STRETCHES FROM MENA UP THROUGH CLARKSVILLE AND
HARRISON IN THE WEST...AND EL DORADO TO BATESVILLE IN THE EAST.
RAPID REFRESH RUC AS WELL AS OTHER HIGH RESOLUTION MODELS
CONTINUE TO INDICATE THE BACK EDGE OF THIS LINE WILL CLEAR A
HARRISON-MENA LINE BY ROUGHLY 10 PM...A BATESVILLE-LITTLE ROCK-
CAMDEN LINE AROUND 1 AM...AND FINALLY MONTICELLO SHORTLY BEFORE
DAY BREAK MONDAY MORNING. HAVE ADJUSTED POP GRIDS ACCORDINGLY.
THE THREAT THREAT FOR TORNADOES...DAMAGING WINDS AND LARGE HAIL
SEEMS TO BE QUICKLY DIMINISHING GIVEN RADAR TRENDS AND INSTABILITY
INDICES. HAVE ALREADY TRIMMED BACK SOME WESTERN COUNTIES FROM
TORNADO WATCH 179. WILL CONTINUE TO MONITOR RADAR TRENDS OVER THE
NEXT FEW HOURS...AND FURTHER TRIM COUNTIES WHEN/WHERE POSSIBLE.
OTHERWISE JUST TWEAKED TEMPS AND WINDS FOR THE OVERNIGHT HOURS.
ALL UPDATED PRODUCTS AND GRIDS ARE OUT.
&&
.PREV DISCUSSION... /ISSUED 615 PM CDT SUN APR 15 2012/
AVIATION...
THE 00Z TAFS WILL BE OUT SHORTLY.
PRIMARY CONCERNS FOR THIS TAF CYCLE WILL BE THUNDERSTORMS. LEADING
EDGE OF SQUALL LINE WAS LOCATED FROM JUST EAST OF ARKADELPHIA NE
THROUGH CONWAY AND UP THROUGH MOUNTAIN VIEW AS OF 2300Z. EXPECT
THIS LINE TO AFFECT KLIT BY RIGHT AT 00Z...KPBF BY 01-02Z...AND
KLLQ AROUND 02Z. WILL ADVERTISE PREVAILING -SHRA WITH VCTS AND
TEMPO TSRA AND MVFR CONDITIONS THROUGH ROUGHLY 04Z FOR ALL SITES
EXCEPT KHRO. BACK EDGE OF LINE IS APPROACHING KHRO AND SHOULD PUSH
EAST OF THERE BY 02Z- 03Z...EAST OF KLIT BY ROUGHLY 07Z AND
FINALLY EAST OF KLLQ BY 08Z- 09Z. AFTER LINE PUSHES THROUGH...A
QUICK RETURN TO VFR CONDITIONS SHOULD BE SEEN...WITH SKC 4-6HRS
AFTER LINE PUSHES THROUGH.
PREV DISCUSSION... /ISSUED 303 PM CDT SUN APR 15 2012/
SHORT TERM...TONIGHT THROUGH WEDNESDAY NIGHT
STORMS HAVING SOME DIFFICULTY INTENSIFYING IN WESTERN ARKANSAS
EARLY THIS AFTERNOON. INSTABILITY GRADUALLY INCREASING...AND
WOULD EXPECT PRECIPITATION TO CONGEAL INTO MORE OF A LINE AS
IT MOVES INTO CENTRAL/EASTERN SECTIONS OF THE STATE THIS EVENING.
SOME STORMS COULD BE SEVERE...WITH WIND DAMAGE THE MAIN CONCERN.
MAIN STORM SYSTEM WILL MOVE WELL TO THE NORTH ON MONDAY...AND THE
FRONT TRIGGERING THE PRECIPITATION WILL STALL FOR A TIME JUST
SOUTHEAST OF THE STATE. GIVEN THIS...ISOLATED TO SCATTERED SHOWERS
AND THUNDERSTORMS COULD LINGER SOUTHEAST OF LITTLE ROCK. OTHERWISE...
CLEARING WILL OCCUR FARTHER NORTH AND WEST...WITH SLIGHTLY
COOLER/DRIER AIR.
PRECIPITATION CHANCES WILL FINALLY COME TO AN END IN THE
SOUTHEAST MONDAY EVENING AS HIGH PRESSURE BUILDS INTO THE REGION
FROM THE PLAINS. THIS WILL KICK THE FRONT TOWARD THE SOUTHEAST
UNITED STATES.
THE REMAINDER OF THE PERIOD WILL FEATURE TRANQUIL CONDITIONS.
TEMPERATURES TUESDAY AND WEDNESDAY WILL BE MOSTLY ABOVE NORMAL.
LONG TERM...THURSDAY THROUGH SUNDAY
FORECAST WILL START OFF DRY AS NEARLY ZONAL FLOW WILL BE IN PLACE
ACROSS THE CENTRAL CONUS AT THE START OF THE LONG TERM.
HOWEVER...UPPER LEVEL TROUGH WILL EXIT THE ROCKIES BY
FRI...DEEPENING OVER THE PLAINS. THIS WILL PUSH A COLD FRONT SOUTH
ACROSS AR BY FRI EVENING. HAVE PRECIP CHANCES STARTING LATE THU
NIGHT ACROSS THE NW...THEN SPREADING SE DURING THE DAY ON FRI AS THE
FRONT TRAVERSES THE STATE. PRECIP CHANCES THEN DECREASE FROM NW TO
SE BY FRI NIGHT INTO SAT AS HIGH PRESSURE DIVES SE ACROSS THE PLAINS.
DRY CONDITIONS WILL THEN PERSIST THROUGH PRETTY MUCH THE REST OF THE
LONG TERM AS NW UPPER FLOW WILL BE DOMINANT ACROSS THE CENTRAL
CONUS.
&&
.PRELIMINARY POINT TEMPS/POPS...
BATESVILLE AR 80 55 72 49 / 70 100 10 10
CAMDEN AR 82 59 80 55 / 80 100 10 10
HARRISON AR 70 49 70 46 / 60 90 10 10
HOT SPRINGS AR 76 55 79 54 / 70 90 10 10
LITTLE ROCK AR 82 58 78 55 / 80 100 10 10
MONTICELLO AR 84 64 80 58 / 70 90 20 10
MOUNT IDA AR 76 53 77 48 / 70 90 10 10
MOUNTAIN HOME AR 74 51 73 46 / 70 90 10 10
NEWPORT AR 83 57 73 49 / 70 100 10 10
PINE BLUFF AR 82 61 78 56 / 70 100 20 10
RUSSELLVILLE AR 79 52 75 48 / 70 90 10 10
SEARCY AR 83 57 76 46 / 70 100 10 10
STUTTGART AR 84 60 77 53 / 70 100 20 10
&&
.LZK WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
64
AREA FORECAST DISCUSSION
NWS BOISE ID
953 AM MDT SAT APR 14 2012
.DISCUSSION...AN AREA OF SHOWERS CONTINUES TO DRIFT TO THE SOUTHWEST
AWAY FROM THE TREASURE VALLEY THIS MORNING...AND EXTENDS FROM THE
SOUTHWEST IDAHO HIGHLANDS INTO SOUTHERN MALHEUR AND SOUTHERN HARNEY
COUNTIES. RECENT GAGE REPORTS ARE INDICTING HOURLY RAINFALL RATES OF
LESS THAN A TENTH OF AN INCH. SCATTERED SHOWERS ARE EXPECTED TO
CONTINUE OVER THE SAME GENERAL AREA THROUGH THIS AFTERNOON PER
LATEST MODEL GUIDANCE. BOI MORNING SOUNDING AND MODEL GUIDANCE
SUPPORTS CONTINUING WITH ISOLATED THUNDERSTORMS THIS AFTERNOON. WILL
ALSO CONTINUE WITH THE WIND ADVISORY FOR LATER THIS AFTERNOON AS
NORTHWEST WINDS INCREASE THROUGH THE DAY. MINOR UPDATES TO
POP/WEATHER/SKY FOR THE REMAINDER OF TODAY.
&&
.AVIATION...WIDESPREAD VFR UNDER MOSTLY CLOUDY SKIES. CHANCE FOR
LOCAL MVFR CONDITIONS IN WIDELY SCATTERED SHOWERS THIS AFTERNOON.
SLIGHT CHANCE FOR THUNDER WITH THESE SHOWERS AS WELL...MAINLY IN SW
IDAHO...FROM 18Z - 00Z. GUSTY NORTHWEST SURFACE WINDS AT 10-20
KTS...WITH STRONGER WINDS FROM KMUO SOUTHEAST THROUGH THE MAGIC
VALLEY AT 25-30 KTS. SURFACE WINDS TO DECREASE DRAMATICALLY AFTER
03Z AND BE LIGHT OVERNIGHT. NNW WINDS ALOFT UP TO 25 KTS AT 10K FEET
MSL. SKIES TO CLEAR OUT OVERNIGHT FOR VFR CONDITIONS SUNDAY.
&&
.PREV DISCUSSION...
SHORT TERM...TODAY THROUGH SUNDAY...AREA OF SHOWERS MOVING FROM SE
TO NW ALONG AND SOUTH OF I-84 BETWEEN WEATHERBY AND GLENNS FERRY AS
OF 3 AM ARE EXPECTED TO CONSOLIDATE AROUND U.S. 95 BETWEEN MARSING
AND MCDERMITT THROUGH THE MORNING AS THE UPPER LOW TO OUR SOUTH
TRACKS THROUGH THE DESERT SW U.S. THE 00Z GFS HINTED AT THIS
PRECIPITATION AREA BUT THE RUC HAD BEEN THE ONLY MODEL TO CAPTURE
THE SHOWERS. NOW THE 6Z NAM IS CATCHING ON TOO. AN UPPER IMPULSE AS
NOTED IN THE 1.5 PV FIELD OVER SE WA TO SW OREGON WILL SPREAD AN
AREA OF LIFT ACROSS OREGON TODAY AND CENTRAL IDAHO THIS AFTERNOON
FOR A CONTINUED THREAT OF SHOWERS...AND ENOUGH INSTABILITY FOR
ISOLATED THUNDERSTORMS AS WELL. BUILDING HIGH PRESSURE ACROSS OREGON
THIS MORNING AND SW IDAHO BY AROUND 20Z WILL SPREAD GUSTY WEST TO NW
WINDS ACROSS THE REGION. SURFACE AND UPPER AIR FLOW ALIGNS WITH
TERRAIN BETWEEN THE BENNETT HILLS AND OWYHEE MOUNTAINS...WHERE
SPEEDS OF 25-35 MPH WITH GUST TO 45 MPH ARE STILL IN THE FORECAST
FOR THE MID AFTERNOON AND EVENING. SO THE WIND ADVISORY WILL REMAIN
IN PLACE FROM SOUTH OF BOISE AROUND GLENNS FERRY TO AROUND JACKPOT.
UPPER IMPULSE IN THE PV FIELD WILL EXIT SOUTH CENTRAL IDAHO BY 6Z
WITH A MILD RIDGE AND LESS WIND EXPECTED ACROSS SE OREGON AND SW
IDAHO SUNDAY.
LONG TERM...SUNDAY NIGHT THROUGH SATURDAY...UNSETTLED WEATHER
EXPECTED NEXT WEEK AS A FAST ZONAL FLOW SETS UP OVER THE NORTH. IN
THIS REGIME...WEAK WAVES WILL MOVE THROUGH THE AREA EVERY DAY OR
TWO. NORMALLY CONFIDENCE IN THE TIMING OF EACH WAVE IS LOW IN THIS
FAST FLOW...HOWEVER CURRENT MODEL CONSENSUS IS UNUSUALLY GOOD.
THEREFORE HAVE TRENDED FORECAST MORE DETERMINISTIC IN THE
MID-RANGE...AND TOWARD CLIMATOLOGY IN THE FAR EXTENDED/NEXT WEEKEND.
EXPECT A CHANCE OF PRECIPITATION JUST ABOUT EVERY DAY...WITH
TEMPERATURES AT OR NEAR NORMAL.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...WIND ADVISORY FROM 2 PM THIS AFTERNOON TO 8 PM MDT THIS EVENING
IDZ014-015-030.
OR...NONE.
&&
$$
WEATHER.GOV/BOISE
DISCUSSION...BW
AVIATION.....CB
PREV SHORT TERM...VM
PREV LONG TERM....BB
AREA FORECAST DISCUSSION
NWS BOISE ID
339 AM MDT SAT APR 14 2012
.SHORT TERM...TODAY THROUGH SUNDAY...AREA OF SHOWERS MOVING FROM
SE TO NW ALONG AND SOUTH OF I-84 BETWEEN WEATHERBY AND GLENNS
FERRY AS OF 3 AM ARE EXPECTED TO CONSOLIDATE AROUND U.S. 95
BETWEEN MARSING AND MCDERMITT THROUGH THE MORNING AS THE UPPER LOW
TO OUR SOUTH TRACKS THROUGH THE DESERT SW U.S. THE 00Z GFS HINTED
AT THIS PRECIPITATION AREA BUT THE RUC HAD BEEN THE ONLY MODEL TO
CAPTURE THE SHOWERS. NOW THE 6Z NAM IS CATCHING ON TOO. AN UPPER
IMPULSE AS NOTED IN THE 1.5 PV FIELD OVER SE WA TO SW OREGON WILL
SPREAD AN AREA OF LIFT ACROSS OREGON TODAY AND CENTRAL IDAHO THIS
AFTERNOON FOR A CONTINUED THREAT OF SHOWERS...AND ENOUGH
INSTABILITY FOR ISOLATED THUNDERSTORMS AS WELL. BUILDING HIGH
PRESSURE ACROSS OREGON THIS MORNING AND SW IDAHO BY AROUND 20Z
WILL SPREAD GUSTY WEST TO NW WINDS ACROSS THE REGION. SURFACE AND
UPPER AIR FLOW ALIGNS WITH TERRAIN BETWEEN THE BENNETT HILLS AND
OWYHEE MOUNTAINS...WHERE SPEEDS OF 25-35 MPH WITH GUST TO 45 MPH
ARE STILL IN THE FORECAST FOR THE MID AFTERNOON AND EVENING. SO
THE WIND ADVISORY WILL REMAIN IN PLACE FROM SOUTH OF BOISE AROUND
GLENNS FERRY TO AROUND JACKPOT. UPPER IMPULSE IN THE PV FIELD WILL
EXIT SOUTH CENTRAL IDAHO BY 6Z WITH A MILD RIDGE AND LESS WIND
EXPECTED ACROSS SE OREGON AND SW IDAHO SUNDAY.
.LONG TERM...SUNDAY NIGHT THROUGH SATURDAY...UNSETTLED WEATHER
EXPECTED NEXT WEEK AS A FAST ZONAL FLOW SETS UP OVER THE NORTH. IN
THIS REGIME...WEAK WAVES WILL MOVE THROUGH THE AREA EVERY DAY OR
TWO. NORMALLY CONFIDENCE IN THE TIMING OF EACH WAVE IS LOW IN THIS
FAST FLOW...HOWEVER CURRENT MODEL CONSENSUS IS UNUSUALLY GOOD.
THEREFORE HAVE TRENDED FORECAST MORE DETERMINISTIC IN THE
MID-RANGE...AND TOWARD CLIMATOLOGY IN THE FAR EXTENDED/NEXT WEEKEND.
EXPECT A CHANCE OF PRECIPITATION JUST ABOUT EVERY DAY...WITH
TEMPERATURES AT OR NEAR NORMAL.
&&
.AVIATION....PREDOMINANTLY VFR WITH ISOLATED MVFR POSSIBLE IN
SHOWERS OVERNIGHT. SCATTERED VFR SHOWERS EXPECTED AGAIN SATURDAY
AFTERNOON WITH INCREASING SURFACE WINDS. SURFACE WINDS...NORTHWEST
UP TO 15 KTS OVERNIGHT...MAINTAINING DIRECTION AND INCREASING TO 20
KTS WITH GUSTS TO 35 KTS SATURDAY AFTERNOON. WINDS ALOFT...NORTHEAST
UP TO 20 KTS OVERNIGHT...BECOMING NORTHWEST UP TO 35 KTS AFTER NOON
SATURDAY.
SUNDAY....VFR UNDER MOSTLY CLEAR SKIES. LIGHT WINDS.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...WIND ADVISORY FROM 2 PM THIS AFTERNOON TO 8 PM MDT THIS EVENING
IDZ014-015-030.
WIND ADVISORY FROM 2 PM THIS AFTERNOON TO 8 PM MDT THIS EVENING
IDZ029.
OR...NONE.
&&
$$
WEATHER.GOV/BOISE
SHORT TERM...VM
LONG TERM....RD
AVIATION.....BB
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1257 PM CDT SAT APR 14 2012
.DISCUSSION...
ISSUED 1040 AM CDT SAT APR 14 2012
UPDATED THE FORECAST TO INCREASE CHANCE OF SHOWERS INTO MIDDAY
WITH THUNDERSTORMS MAINLY CONFINED TO SOUTHEAST IL. CONVECTION
SHOULD DIMINISH DURING THE AFTERNOON AND COULD SEE SOME PEEKS OF
SUNSHINE LATER TODAY. HIGHS IN THE UPPER 60S AND LOWER 70S WITH
MILDEST READINGS SE OF I-70 AND WEST OF PEORIA AND SPRINGFIELD.
SOUTH WINDS 8 TO 15 MPH WITH GUSTS UP TO 20 MPH.
A COUPLE OF MCS/S PASSED OVER CENTRAL AND SE IL THIS MORNING WITH
1ST MCS MAINLY GIVING RAINS OVERNIGHT SOUTH OF I-72 AND 2ND MCS
THIS MORNING GETING RAINS AS FAR NORTH AS KNOX...STARK AND MARSHALL
COUNTIES. 3RD MCS WAS OVER CENTRAL MO. COOP OBSERVER IN MATTOON IN
CENTRAL COLES COUNTY MEASURED 1.65 INCHES OF RAIN THROUGH 8 AM AND
LIKELY OVER 2 INCHES BY LATE MORNING WITH SOME WATER IN THE
STREETS. AN URBANA AND SMALL STREAM FLOOD ADVISORY WAS ISSUED FOR
COLES... CENTRAL/SE SHELBY...SE MOULTRIE AND NW CUMBERLAND COUNTY
UNTIL 130 PM. THUNDERSTORMS WITH HEAVIEST RAINS WERE FROM TERRE
HAUTE...TO ROBINSON TO OLNEY AND MOVING ENE. RAIN SHOWERS THAT
WERE HEAVY AT TIMES WERE ALREADY BREAKING UP OVER CENTRAL IL AND
EXPECT THIS TREND TO CONTINUE THIS AFTERNOON AS CONVECTION BECOMES
MORE WIDELY SCATTERED TO SCATTERED IN NATURE BY MID/LATE AFTERNOON.
SPC KEEPS SLIGHT RISK OF SEVERE STORMS JUST WEST KNOX AND SCHUYLER
COUNTY BUT COULD BE A FEW STRONG STORMS WITH SMALL HAIL IN SE
IL...SOUTHEAST OF I-70 NEXT FEW HOURS. HAD REPORT OF PEA SIZE HAIL
IN MATTOON AROUND 830 AM. 1000 MB AND DEEPENING LOW PRESSURE OVER
CENTRAL CO HAS A WARM FRONT EXTENDING EAST INTO CENTRAL MO AND FAR
SOUTHERN IL SOUTH OF I-64. 12Z MODELS LIFT WARM FRONT NORTH
THROUGH CENTRAL IL THIS AFTERNOON AND FOCUS FOR CONVECTION WILL
SHIFT INTO NORTHERN IL/IN LATER THIS AFTERNOON AND TONIGHT. TEMPS
CURRENTLY IN THE UPPER 50S AND LOWER 60S AND MOIST DEWPOINTS IN
THE MID TO UPPER 50S WITH JACKSONVILLE DEWPOINT UP TO 61F. TEMPS
SHOULD CLIMB ANOTHER 10 DEGREES WITH SOME SUNSHINE APPEARING LATER
TODAY WITH HIGHS IN THE UPPER 60S AND LOWER 70S.
HUETTL
&&
.AVIATION...
ISSUED 1255 PM CDT SAT APR 14 2012
CONTINUED LIGHT TO MODERATE RAIN SHOWERS WITH MVFR VSBYS AND IFR
CEILINGS 500-1K FT INTO MID AFTERNOON THROUGH 21Z/4 PM OVER THE
CENTRAL IL TERMINAL AS AN MCS WEAKENS OVER CENTRAL IL DURING THIS
AFTERNOON. HEAVIEST RAIN SHOWERS TO OCCUR NEXT FEW HOURS ALONG
I-72 TAF SITES. SCATTERED THUNDERSTORMS STAYED SOUTH OF I-72 THIS
MORNING AND HAVE PUSHED EAST OF IL INTO SOUTHEAST INDIANA BY EARLY
AFTERNOON. ISOLATED THUNDERSTORMS COULD DEVELOP DURING MID/LATE
AFTERNOON AS WARM FRONT LIFTS NORTHWARD ACROSS CENTRAL IL IN HUMID
AIRMASS BUT COVERAGE APPEARS TOO LIMITED TO MENTION IN THE TAFS AT
THIS TIME. HEATING AND CORRESPONDING INSTABILITY IS LIMITED BY
WIDESPREAD SHOWERS AND CANOPY OF LOW CLOUDS OVER CENTRAL IL AT
MIDDAY. SSW WINDS 8-14 KTS THIS AFTERNOON AND TONIGHT TO INCREASE TO
15-20 KTS LATER TONIGHT AND EARLY SUNDAY MORNING...AND STRENGHTHEN
TO 20 TO 25 KTS WITH GUSTS OF 25 TO 35 KTS AFTER 14Z/9 AM SUNDAY.
BEST CHANCES OF CONVECTION WILL BE NORTH AND WEST OF CENTRAL IL
TONIGHT INTO EARLY SUNDAY AFTERNOON. MVFR CEILINGS AND VISIBILITIES
STILL POSSIBLE TONIGHT AND EARLY SUNDAY MORNING. DEEPENING 996 MB
LOW PRESSURE OVER CENTRAL CO WITH WARM FRONT EXTENDING EAST INTO
NORTHERN MO AND SOUTHERN IL. LATEST MODELS DEEPENING STRONG LOW
PRESSURE TO 983 MB AS IT TRACKS NE INTO SOUTHEAST SD BY 18Z/1 PM
SUNDAY...WHILE LIFTING WARM FRONT NORTHWARD INTO CENTRAL WI AND COLD
FRONT OVER THE CENTRAL PLAINS AND APPROACHING WESTERN MO/IA EARLY
SUNDAY AFTERNOON.
HUETTL
&&
.PREV DISCUSSION...
ISSUED 247 AM CDT SAT APR 14 2012
SHORT TERM...TODAY THROUGH MONDAY
WARM FRONT CURRENTLY STRETCHING ACROSS KANSAS AND MISSOURI WILL
LIFT NORTHWARD TODAY...PROVIDING THE FOCUS FOR SHOWERS AND
THUNDERSTORMS. 07Z SATELLITE/RADAR IMAGERY SHOWS CLUSTERS OF
STORMS TRACKING E/NE ALONG THE FRONT...HOWEVER 00Z MODEL DATA IS
NOT HANDLING THE CURRENT CONVECTIVE TRENDS VERY WELL AT ALL.
NAM/GFS/ECMWF ALL SHIFT THE PRECIP NORTHWARD ACROSS ALL OF CENTRAL
ILLINOIS BY 12Z...HOWEVER LATEST RADAR LOOPS ARE NOT SUPPORTING
THIS. BASED ON RADAR TRENDS AND THE SOUTHWESTERLY UPPER FLOW
PATTERN IN PLACE ACROSS THE REGION...THINK A CONTINUED E/NE
TRAJECTORY IS MORE PROBABLE. AS A RESULT...HIGHEST RAIN CHANCES
WILL LIKELY BE CONFINED TO THE SOUTHERN KILX CWA TODAY...MAINLY
SOUTH OF THE I-72 CORRIDOR. 04Z HRRR SEEMS TO HAVE THE BEST HANDLE
ON THINGS AND SUGGESTS THE NORTH MAY REMAIN LARGELY DRY AT LEAST
THROUGH 18Z. SCATTERED SHOWERS/STORMS MAY DEVELOP ALONG/NORTH OF
I-74 THIS AFTERNOON AS THE WARM FRONT SHIFTS SLOWLY
NORTHWARD...ALTHOUGH THINK MODELS ARE TRYING TO PUSH BOUNDARY
NORTH TOO QUICKLY. END RESULT WILL BE A MOSTLY CLOUDY DAY ACROSS
THE BOARD WITH CATEGORICAL POPS ACROSS THE SOUTH...TAPERING DOWN
TO SLIGHT CHANCES ACROSS THE NORTH. DUE TO THE CLOUDS AND
PRECIP...TEMPS WILL BE HELD A FEW DEGREES BELOW MAV
GUIDANCE...GENERALLY REMAINING IN THE UPPER 60S AND LOWER 70S.
AS LOW PRESSURE DEEPENS AND LIFTS NORTHEASTWARD FROM COLORADO THIS
EVENING TO SOUTHEAST SOUTH DAKOTA BY EARLY SUNDAY MORNING...THE
WARM FRONT WILL LIFT NORTH OF CENTRAL ILLINOIS TONIGHT. SCATTERED
SHOWERS/STORMS WILL BE POSSIBLE IN THE VICINITY OF THE BOUNDARY
THIS EVENING...BUT RAIN CHANCES WILL DWINDLE OVERNIGHT AS FORCING
IS LOST.
WINDY AND VERY WARM WEATHER WILL BE ON TAP FOR SUNDAY...AS LOW
PRESSURE LIFTS TOWARD THE WESTERN GREAT LAKES. TIGHTENING PRESSURE
GRADIENT AND INCREASING LOW-LEVEL JET WILL SUPPORT SOUTHWESTERLY
WINDS OF 20 TO 30 MPH...WITH GUSTS UP TO 40 MPH AT TIMES. A WIND
ADVISORY WILL LIKELY BE NEEDED...AS MIXING COULD POTENTIALLY BRING
EVEN HIGHER GUSTS DOWN TO THE SURFACE SUNDAY AFTERNOON. WILL HOLD
OFF ON ISSUANCE FOR NOW...PENDING ADDITIONAL SUPPORT FROM FORECAST
SOUNDINGS. WITH PARTIAL SUNSHINE AND STRONG WAA...HIGH TEMPS WILL
SOAR INTO THE UPPER 70S AND LOWER 80S.
TRAILING COLD FRONT WILL APPROACH FROM THE WEST BY LATE SUNDAY
AFTERNOON...ACCOMPANIED BY A BROKEN LINE OF THUNDERSTORMS. WHILE
BEST UPPER SUPPORT WILL SLIDE BY TO THE N/NW AND GREATEST
INSTABILITY WILL REMAIN TO THE S/SW...THINK POTENT MID/LOW-LEVEL
JETS WILL BE ENOUGH TO SUPPORT STRONG STORMS CAPABLE OF DAMAGING
WIND GUSTS. FORECAST SOUNDINGS INDICATE 0-3KM STORM RELATIVE
HELICITY VALUES INCREASING TO 400 TO 500 BY 00Z MON...WITH MOST OF
THIS INCREASE DUE TO SPEED SHEAR. ANY STORMS THAT FIRE IN THIS
ENVIRONMENT WILL BE FAST-MOVING AND CAPABLE OF BRINGING DAMAGING
WIND GUSTS DOWN TO THE SURFACE. MODEL CONSENSUS TRACKS LINE OF
STORMS INTO THE ILLINOIS RIVER VALLEY AFTER 21Z...THEN INTO
EAST-CENTRAL ILLINOIS AFTER 06Z.
FRONT AND ASSOCIATED STORMS WILL EXIT CENTRAL ILLINOIS LATE SUNDAY
NIGHT...FOLLOWED BY WINDY AND COOLER WEATHER ON MONDAY. TIGHT
PRESSURE GRADIENT ON THE BACK SIDE OF THE DEPARTING SYSTEM WILL
SUPPORT W/NW WINDS GUSTING UP TO 30 MPH...WHILE HIGH TEMPS DROP
BACK INTO THE 60S.
LONG TERM...TUESDAY THROUGH FRIDAY
ZONAL UPPER FLOW PATTERN WILL BE IN PLACE THROUGH THE
EXTENDED...ALLOWING A SERIES OF FAST-MOVING STORM SYSTEMS TO PASS
THROUGH THE REGION. A RATHER WEAK IMPULSE WILL TRACK THROUGH THE
UPPER MIDWEST INTO THE GREAT LAKES ON WEDNESDAY...HOWEVER BEST
LIFT WILL REMAIN WELL TO THE NORTH AND DEEP MOISTURE WILL BE
LACKING. AS A RESULT...HAVE ONLY INCLUDED SLIGHT CHANCE POPS
WEDNESDAY/WEDNESDAY NIGHT AS A WEAK BOUNDARY SLIDES THROUGH. BOTH
THE GFS AND ECMWF CONTINUE TO INDICATE A STRONGER WAVE APPROACHING
BY THE END OF THE WEEK...RESULTING IN A BETTER CHANCE FOR
SHOWERS/STORMS ON FRIDAY.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1045 AM CDT SAT APR 14 2012
.DISCUSSION...
ISSUED 1040 AM CDT SAT APR 14 2012
UPDATED THE FORECAST TO INCREASE CHANCE OF SHOWERS INTO MIDDAY
WITH THUNDERSTORMS MAINLY CONFINED TO SOUTHEAST IL. CONVECTION
SHOULD DIMINISH DURING THE AFTERNOON AND COULD SEE SOME PEEKS OF
SUNSHINE LATER TODAY. HIGHS IN THE UPPER 60S AND LOWER 70S WITH
MILDEST READINGS SE OF I-70 AND WEST OF PEORIA AND SPRINGFIELD.
SOUTH WINDS 8 TO 15 MPH WITH GUSTS UP TO 20 MPH.
A COUPLE OF MCS/S PASSED OVER CENTRAL AND SE IL THIS MORNING WITH
1ST MCS MAINLY GIVING RAINS OVERNIGHT SOUTH OF I-72 AND 2ND MCS
THIS MORNING GETING RAINS AS FAR NORTH AS KNOX...STARK AND MARSHALL
COUNTIES. 3RD MCS WAS OVER CENTRAL MO. COOP OBSERVER IN MATTOON IN
CENTRAL COLES COUNTY MEASURED 1.65 INCHES OF RAIN THROUGH 8 AM AND
LIKELY OVER 2 INCHES BY LATE MORNING WITH SOME WATER IN THE
STREETS. AN URBANA AND SMALL STREAM FLOOD ADVISORY WAS ISSUED FOR
COLES... CENTRAL/SE SHELBY...SE MOULTRIE AND NW CUMBERLAND COUNTY
UNTIL 130 PM. THUNDERSTORMS WITH HEAVIEST RAINS WERE FROM TERRE
HAUTE...TO ROBINSON TO OLNEY AND MOVING ENE. RAIN SHOWERS THAT
WERE HEAVY AT TIMES WERE ALREADY BREAKING UP OVER CENTRAL IL AND
EXPECT THIS TREND TO CONTINUE THIS AFTERNOON AS CONVECTION BECOMES
MORE WIDELY SCATTERED TO SCATTERED IN NATURE BY MID/LATE AFTERNOON.
SPC KEEPS SLIGHT RISK OF SEVERE STORMS JUST WEST KNOX AND SCHUYLER
COUNTY BUT COULD BE A FEW STRONG STORMS WITH SMALL HAIL IN SE
IL...SOUTHEAST OF I-70 NEXT FEW HOURS. HAD REPORT OF PEA SIZE HAIL
IN MATTOON AROUND 830 AM. 1000 MB AND DEEPENING LOW PRESSURE OVER
CENTRAL CO HAS A WARM FRONT EXTENDING EAST INTO CENTRAL MO AND FAR
SOUTHERN IL SOUTH OF I-64. 12Z MODELS LIFT WARM FRONT NORTH
THROUGH CENTRAL IL THIS AFTERNOON AND FOCUS FOR CONVECTION WILL
SHIFT INTO NORTHERN IL/IN LATER THIS AFTERNOON AND TONIGHT. TEMPS
CURRENTLY IN THE UPPER 50S AND LOWER 60S AND MOIST DEWPOINTS IN
THE MID TO UPPER 50S WITH JACKSONVILLE DEWPOINT UP TO 61F. TEMPS
SHOULD CLIMB ANOTHER 10 DEGREES WITH SOME SUNSHINE APPEARING LATER
TODAY WITH HIGHS IN THE UPPER 60S AND LOWER 70S.
HUETTL
&&
.AVIATION...
ISSUED 615 AM CDT SAT APR 14 2012
THE MAIN FORECAST CHALLENGE THIS PERIOD WILL BE COVERAGE OF SHOWERS
AND THUNDERSTORMS AND MVFR OR LOWER CIGS. WARM FRONT WAS LOCATED
OVER SOUTH CENTRAL MISSOURI EARLY THIS MORNING AND IS FORECAST TO
SHIFT NORTH LATE TODAY. SCATTERED SHOWERS AND THUNDERSTORMS HAVE
BEEN OCCURRING MAINLY TO THE SOUTH OF THE TAF SITES OVERNIGHT BUT
EXPECT A NORTHWARD DRIFT TO THE RAIN TODAY AS THE WARM FRONT LIFTS
SLOWLY NORTH. FORECAST SOUNDINGS CONTINUE TO INDICATE A GRADUAL
LOWERING OF CIGS TO MVFR THIS MORNING AS THE RAIN AND SCT TSRA LIFT
NORTH ACRS THE TAF SITES. CURRENT TAFS HAVE THIS INDICATED BUT WILL
TRY TO FINE TUNE THE TIMING OF THE MOST CONCENTRATED SHOWERS AND
THUNDERSTORMS AND LOW CIGS THIS MRNG INTO THE AFTN HOURS. THE WARM
FRONT WILL LIFT NORTH OF THE TAF SITES AFTR 02Z TAKING MOST OF THE
RAIN AND LOWER CIGS WITH IT. WILL BREAK OUT OF THE MVFR CIGS AND
SHOWERS AS THE WARM FRONT LIFTS NORTH OF OUR TAF SITES THIS EVE.
SOUTH WINDS WILL AVERAGE FROM 10 TO 15 KTS...WITH OCCASIONAL GUSTS
UP TO 20 KTS...ESPECIALLY AT SPI AND DEC WHICH SHOULD SEE THE WARM
FRONT SHIFT TO THEIR NORTH LATER THIS AFTERNOON. GUSTY SOUTH WINDS
EXPECTED AT ALL TAF LOCATIONS TONIGHT AT 12 TO 17 KTS WITH GUSTS
UP TO 25 KTS AT TIMES.
SMITH
&&
.PREV DISCUSSION...
ISSUED 247 AM CDT SAT APR 14 2012
SHORT TERM...TODAY THROUGH MONDAY
WARM FRONT CURRENTLY STRETCHING ACROSS KANSAS AND MISSOURI WILL
LIFT NORTHWARD TODAY...PROVIDING THE FOCUS FOR SHOWERS AND
THUNDERSTORMS. 07Z SATELLITE/RADAR IMAGERY SHOWS CLUSTERS OF
STORMS TRACKING E/NE ALONG THE FRONT...HOWEVER 00Z MODEL DATA IS
NOT HANDLING THE CURRENT CONVECTIVE TRENDS VERY WELL AT ALL.
NAM/GFS/ECMWF ALL SHIFT THE PRECIP NORTHWARD ACROSS ALL OF CENTRAL
ILLINOIS BY 12Z...HOWEVER LATEST RADAR LOOPS ARE NOT SUPPORTING
THIS. BASED ON RADAR TRENDS AND THE SOUTHWESTERLY UPPER FLOW
PATTERN IN PLACE ACROSS THE REGION...THINK A CONTINUED E/NE
TRAJECTORY IS MORE PROBABLE. AS A RESULT...HIGHEST RAIN CHANCES
WILL LIKELY BE CONFINED TO THE SOUTHERN KILX CWA TODAY...MAINLY
SOUTH OF THE I-72 CORRIDOR. 04Z HRRR SEEMS TO HAVE THE BEST HANDLE
ON THINGS AND SUGGESTS THE NORTH MAY REMAIN LARGELY DRY AT LEAST
THROUGH 18Z. SCATTERED SHOWERS/STORMS MAY DEVELOP ALONG/NORTH OF
I-74 THIS AFTERNOON AS THE WARM FRONT SHIFTS SLOWLY
NORTHWARD...ALTHOUGH THINK MODELS ARE TRYING TO PUSH BOUNDARY
NORTH TOO QUICKLY. END RESULT WILL BE A MOSTLY CLOUDY DAY ACROSS
THE BOARD WITH CATEGORICAL POPS ACROSS THE SOUTH...TAPERING DOWN
TO SLIGHT CHANCES ACROSS THE NORTH. DUE TO THE CLOUDS AND
PRECIP...TEMPS WILL BE HELD A FEW DEGREES BELOW MAV
GUIDANCE...GENERALLY REMAINING IN THE UPPER 60S AND LOWER 70S.
AS LOW PRESSURE DEEPENS AND LIFTS NORTHEASTWARD FROM COLORADO THIS
EVENING TO SOUTHEAST SOUTH DAKOTA BY EARLY SUNDAY MORNING...THE
WARM FRONT WILL LIFT NORTH OF CENTRAL ILLINOIS TONIGHT. SCATTERED
SHOWERS/STORMS WILL BE POSSIBLE IN THE VICINITY OF THE BOUNDARY
THIS EVENING...BUT RAIN CHANCES WILL DWINDLE OVERNIGHT AS FORCING
IS LOST.
WINDY AND VERY WARM WEATHER WILL BE ON TAP FOR SUNDAY...AS LOW
PRESSURE LIFTS TOWARD THE WESTERN GREAT LAKES. TIGHTENING PRESSURE
GRADIENT AND INCREASING LOW-LEVEL JET WILL SUPPORT SOUTHWESTERLY
WINDS OF 20 TO 30 MPH...WITH GUSTS UP TO 40 MPH AT TIMES. A WIND
ADVISORY WILL LIKELY BE NEEDED...AS MIXING COULD POTENTIALLY BRING
EVEN HIGHER GUSTS DOWN TO THE SURFACE SUNDAY AFTERNOON. WILL HOLD
OFF ON ISSUANCE FOR NOW...PENDING ADDITIONAL SUPPORT FROM FORECAST
SOUNDINGS. WITH PARTIAL SUNSHINE AND STRONG WAA...HIGH TEMPS WILL
SOAR INTO THE UPPER 70S AND LOWER 80S.
TRAILING COLD FRONT WILL APPROACH FROM THE WEST BY LATE SUNDAY
AFTERNOON...ACCOMPANIED BY A BROKEN LINE OF THUNDERSTORMS. WHILE
BEST UPPER SUPPORT WILL SLIDE BY TO THE N/NW AND GREATEST
INSTABILITY WILL REMAIN TO THE S/SW...THINK POTENT MID/LOW-LEVEL
JETS WILL BE ENOUGH TO SUPPORT STRONG STORMS CAPABLE OF DAMAGING
WIND GUSTS. FORECAST SOUNDINGS INDICATE 0-3KM STORM RELATIVE
HELICITY VALUES INCREASING TO 400 TO 500 BY 00Z MON...WITH MOST OF
THIS INCREASE DUE TO SPEED SHEAR. ANY STORMS THAT FIRE IN THIS
ENVIRONMENT WILL BE FAST-MOVING AND CAPABLE OF BRINGING DAMAGING
WIND GUSTS DOWN TO THE SURFACE. MODEL CONSENSUS TRACKS LINE OF
STORMS INTO THE ILLINOIS RIVER VALLEY AFTER 21Z...THEN INTO
EAST-CENTRAL ILLINOIS AFTER 06Z.
FRONT AND ASSOCIATED STORMS WILL EXIT CENTRAL ILLINOIS LATE SUNDAY
NIGHT...FOLLOWED BY WINDY AND COOLER WEATHER ON MONDAY. TIGHT
PRESSURE GRADIENT ON THE BACK SIDE OF THE DEPARTING SYSTEM WILL
SUPPORT W/NW WINDS GUSTING UP TO 30 MPH...WHILE HIGH TEMPS DROP
BACK INTO THE 60S.
LONG TERM...TUESDAY THROUGH FRIDAY
ZONAL UPPER FLOW PATTERN WILL BE IN PLACE THROUGH THE
EXTENDED...ALLOWING A SERIES OF FAST-MOVING STORM SYSTEMS TO PASS
THROUGH THE REGION. A RATHER WEAK IMPULSE WILL TRACK THROUGH THE
UPPER MIDWEST INTO THE GREAT LAKES ON WEDNESDAY...HOWEVER BEST
LIFT WILL REMAIN WELL TO THE NORTH AND DEEP MOISTURE WILL BE
LACKING. AS A RESULT...HAVE ONLY INCLUDED SLIGHT CHANCE POPS
WEDNESDAY/WEDNESDAY NIGHT AS A WEAK BOUNDARY SLIDES THROUGH. BOTH
THE GFS AND ECMWF CONTINUE TO INDICATE A STRONGER WAVE APPROACHING
BY THE END OF THE WEEK...RESULTING IN A BETTER CHANCE FOR
SHOWERS/STORMS ON FRIDAY.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
626 AM CDT SAT APR 14 2012
.DISCUSSION...
ISSUED 247 AM CDT SAT APR 14 2012
SHORT TERM...TODAY THROUGH MONDAY
WARM FRONT CURRENTLY STRETCHING ACROSS KANSAS AND MISSOURI WILL
LIFT NORTHWARD TODAY...PROVIDING THE FOCUS FOR SHOWERS AND
THUNDERSTORMS. 07Z SATELLITE/RADAR IMAGERY SHOWS CLUSTERS OF
STORMS TRACKING E/NE ALONG THE FRONT...HOWEVER 00Z MODEL DATA IS
NOT HANDLING THE CURRENT CONVECTIVE TRENDS VERY WELL AT ALL.
NAM/GFS/ECMWF ALL SHIFT THE PRECIP NORTHWARD ACROSS ALL OF CENTRAL
ILLINOIS BY 12Z...HOWEVER LATEST RADAR LOOPS ARE NOT SUPPORTING
THIS. BASED ON RADAR TRENDS AND THE SOUTHWESTERLY UPPER FLOW
PATTERN IN PLACE ACROSS THE REGION...THINK A CONTINUED E/NE
TRAJECTORY IS MORE PROBABLE. AS A RESULT...HIGHEST RAIN CHANCES
WILL LIKELY BE CONFINED TO THE SOUTHERN KILX CWA TODAY...MAINLY
SOUTH OF THE I-72 CORRIDOR. 04Z HRRR SEEMS TO HAVE THE BEST HANDLE
ON THINGS AND SUGGESTS THE NORTH MAY REMAIN LARGELY DRY AT LEAST
THROUGH 18Z. SCATTERED SHOWERS/STORMS MAY DEVELOP ALONG/NORTH OF
I-74 THIS AFTERNOON AS THE WARM FRONT SHIFTS SLOWLY
NORTHWARD...ALTHOUGH THINK MODELS ARE TRYING TO PUSH BOUNDARY
NORTH TOO QUICKLY. END RESULT WILL BE A MOSTLY CLOUDY DAY ACROSS
THE BOARD WITH CATEGORICAL POPS ACROSS THE SOUTH...TAPERING DOWN
TO SLIGHT CHANCES ACROSS THE NORTH. DUE TO THE CLOUDS AND
PRECIP...TEMPS WILL BE HELD A FEW DEGREES BELOW MAV
GUIDANCE...GENERALLY REMAINING IN THE UPPER 60S AND LOWER 70S.
AS LOW PRESSURE DEEPENS AND LIFTS NORTHEASTWARD FROM COLORADO THIS
EVENING TO SOUTHEAST SOUTH DAKOTA BY EARLY SUNDAY MORNING...THE
WARM FRONT WILL LIFT NORTH OF CENTRAL ILLINOIS TONIGHT. SCATTERED
SHOWERS/STORMS WILL BE POSSIBLE IN THE VICINITY OF THE BOUNDARY
THIS EVENING...BUT RAIN CHANCES WILL DWINDLE OVERNIGHT AS FORCING
IS LOST.
WINDY AND VERY WARM WEATHER WILL BE ON TAP FOR SUNDAY...AS LOW
PRESSURE LIFTS TOWARD THE WESTERN GREAT LAKES. TIGHTENING PRESSURE
GRADIENT AND INCREASING LOW-LEVEL JET WILL SUPPORT SOUTHWESTERLY
WINDS OF 20 TO 30 MPH...WITH GUSTS UP TO 40 MPH AT TIMES. A WIND
ADVISORY WILL LIKELY BE NEEDED...AS MIXING COULD POTENTIALLY BRING
EVEN HIGHER GUSTS DOWN TO THE SURFACE SUNDAY AFTERNOON. WILL HOLD
OFF ON ISSUANCE FOR NOW...PENDING ADDITIONAL SUPPORT FROM FORECAST
SOUNDINGS. WITH PARTIAL SUNSHINE AND STRONG WAA...HIGH TEMPS WILL
SOAR INTO THE UPPER 70S AND LOWER 80S.
TRAILING COLD FRONT WILL APPROACH FROM THE WEST BY LATE SUNDAY
AFTERNOON...ACCOMPANIED BY A BROKEN LINE OF THUNDERSTORMS. WHILE
BEST UPPER SUPPORT WILL SLIDE BY TO THE N/NW AND GREATEST
INSTABILITY WILL REMAIN TO THE S/SW...THINK POTENT MID/LOW-LEVEL
JETS WILL BE ENOUGH TO SUPPORT STRONG STORMS CAPABLE OF DAMAGING
WIND GUSTS. FORECAST SOUNDINGS INDICATE 0-3KM STORM RELATIVE
HELICITY VALUES INCREASING TO 400 TO 500 BY 00Z MON...WITH MOST OF
THIS INCREASE DUE TO SPEED SHEAR. ANY STORMS THAT FIRE IN THIS
ENVIRONMENT WILL BE FAST-MOVING AND CAPABLE OF BRINGING DAMAGING
WIND GUSTS DOWN TO THE SURFACE. MODEL CONSENSUS TRACKS LINE OF
STORMS INTO THE ILLINOIS RIVER VALLEY AFTER 21Z...THEN INTO
EAST-CENTRAL ILLINOIS AFTER 06Z.
FRONT AND ASSOCIATED STORMS WILL EXIT CENTRAL ILLINOIS LATE SUNDAY
NIGHT...FOLLOWED BY WINDY AND COOLER WEATHER ON MONDAY. TIGHT
PRESSURE GRADIENT ON THE BACK SIDE OF THE DEPARTING SYSTEM WILL
SUPPORT W/NW WINDS GUSTING UP TO 30 MPH...WHILE HIGH TEMPS DROP
BACK INTO THE 60S.
LONG TERM...TUESDAY THROUGH FRIDAY
ZONAL UPPER FLOW PATTERN WILL BE IN PLACE THROUGH THE
EXTENDED...ALLOWING A SERIES OF FAST-MOVING STORM SYSTEMS TO PASS
THROUGH THE REGION. A RATHER WEAK IMPULSE WILL TRACK THROUGH THE
UPPER MIDWEST INTO THE GREAT LAKES ON WEDNESDAY...HOWEVER BEST
LIFT WILL REMAIN WELL TO THE NORTH AND DEEP MOISTURE WILL BE
LACKING. AS A RESULT...HAVE ONLY INCLUDED SLIGHT CHANCE POPS
WEDNESDAY/WEDNESDAY NIGHT AS A WEAK BOUNDARY SLIDES THROUGH. BOTH
THE GFS AND ECMWF CONTINUE TO INDICATE A STRONGER WAVE APPROACHING
BY THE END OF THE WEEK...RESULTING IN A BETTER CHANCE FOR
SHOWERS/STORMS ON FRIDAY.
&&
.AVIATION...
ISSUED 615 AM CDT SAT APR 14 2012
THE MAIN FORECAST CHALLENGE THIS PERIOD WILL BE COVERAGE OF SHOWERS
AND THUNDERSTORMS AND MVFR OR LOWER CIGS. WARM FRONT WAS LOCATED
OVER SOUTH CENTRAL MISSOURI EARLY THIS MORNING AND IS FORECAST TO
SHIFT NORTH LATE TODAY. SCATTERED SHOWERS AND THUNDERSTORMS HAVE
BEEN OCCURRING MAINLY TO THE SOUTH OF THE TAF SITES OVERNIGHT BUT
EXPECT A NORTHWARD DRIFT TO THE RAIN TODAY AS THE WARM FRONT LIFTS
SLOWLY NORTH. FORECAST SOUNDINGS CONTINUE TO INDICATE A GRADUAL
LOWERING OF CIGS TO MVFR THIS MORNING AS THE RAIN AND SCT TSRA LIFT
NORTH ACRS THE TAF SITES. CURRENT TAFS HAVE THIS INDICATED BUT WILL
TRY TO FINE TUNE THE TIMING OF THE MOST CONCENTRATED SHOWERS AND
THUNDERSTORMS AND LOW CIGS THIS MRNG INTO THE AFTN HOURS. THE WARM
FRONT WILL LIFT NORTH OF THE TAF SITES AFTR 02Z TAKING MOST OF THE
RAIN AND LOWER CIGS WITH IT. WILL BREAK OUT OF THE MVFR CIGS AND
SHOWERS AS THE WARM FRONT LIFTS NORTH OF OUR TAF SITES THIS EVE.
SOUTH WINDS WILL AVERAGE FROM 10 TO 15 KTS...WITH OCCASIONAL GUSTS
UP TO 20 KTS...ESPECIALLY AT SPI AND DEC WHICH SHOULD SEE THE WARM
FRONT SHIFT TO THEIR NORTH LATER THIS AFTERNOON. GUSTY SOUTH WINDS
EXPECTED AT ALL TAF LOCATIONS TONIGHT AT 12 TO 17 KTS WITH GUSTS
UP TO 25 KTS AT TIMES.
SMITH
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
247 AM CDT SAT APR 14 2012
.DISCUSSION...
ISSUED 247 AM CDT SAT APR 14 2012
SHORT TERM...TODAY THROUGH MONDAY
WARM FRONT CURRENTLY STRETCHING ACROSS KANSAS AND MISSOURI WILL
LIFT NORTHWARD TODAY...PROVIDING THE FOCUS FOR SHOWERS AND
THUNDERSTORMS. 07Z SATELLITE/RADAR IMAGERY SHOWS CLUSTERS OF
STORMS TRACKING E/NE ALONG THE FRONT...HOWEVER 00Z MODEL DATA IS
NOT HANDLING THE CURRENT CONVECTIVE TRENDS VERY WELL AT ALL.
NAM/GFS/ECMWF ALL SHIFT THE PRECIP NORTHWARD ACROSS ALL OF CENTRAL
ILLINOIS BY 12Z...HOWEVER LATEST RADAR LOOPS ARE NOT SUPPORTING
THIS. BASED ON RADAR TRENDS AND THE SOUTHWESTERLY UPPER FLOW
PATTERN IN PLACE ACROSS THE REGION...THINK A CONTINUED E/NE
TRAJECTORY IS MORE PROBABLE. AS A RESULT...HIGHEST RAIN CHANCES
WILL LIKELY BE CONFINED TO THE SOUTHERN KILX CWA TODAY...MAINLY
SOUTH OF THE I-72 CORRIDOR. 04Z HRRR SEEMS TO HAVE THE BEST HANDLE
ON THINGS AND SUGGESTS THE NORTH MAY REMAIN LARGELY DRY AT LEAST
THROUGH 18Z. SCATTERED SHOWERS/STORMS MAY DEVELOP ALONG/NORTH OF
I-74 THIS AFTERNOON AS THE WARM FRONT SHIFTS SLOWLY
NORTHWARD...ALTHOUGH THINK MODELS ARE TRYING TO PUSH BOUNDARY
NORTH TOO QUICKLY. END RESULT WILL BE A MOSTLY CLOUDY DAY ACROSS
THE BOARD WITH CATEGORICAL POPS ACROSS THE SOUTH...TAPERING DOWN
TO SLIGHT CHANCES ACROSS THE NORTH. DUE TO THE CLOUDS AND
PRECIP...TEMPS WILL BE HELD A FEW DEGREES BELOW MAV
GUIDANCE...GENERALLY REMAINING IN THE UPPER 60S AND LOWER 70S.
AS LOW PRESSURE DEEPENS AND LIFTS NORTHEASTWARD FROM COLORADO THIS
EVENING TO SOUTHEAST SOUTH DAKOTA BY EARLY SUNDAY MORNING...THE
WARM FRONT WILL LIFT NORTH OF CENTRAL ILLINOIS TONIGHT. SCATTERED
SHOWERS/STORMS WILL BE POSSIBLE IN THE VICINITY OF THE BOUNDARY
THIS EVENING...BUT RAIN CHANCES WILL DWINDLE OVERNIGHT AS FORCING
IS LOST.
WINDY AND VERY WARM WEATHER WILL BE ON TAP FOR SUNDAY...AS LOW
PRESSURE LIFTS TOWARD THE WESTERN GREAT LAKES. TIGHTENING PRESSURE
GRADIENT AND INCREASING LOW-LEVEL JET WILL SUPPORT SOUTHWESTERLY
WINDS OF 20 TO 30 MPH...WITH GUSTS UP TO 40 MPH AT TIMES. A WIND
ADVISORY WILL LIKELY BE NEEDED...AS MIXING COULD POTENTIALLY BRING
EVEN HIGHER GUSTS DOWN TO THE SURFACE SUNDAY AFTERNOON. WILL HOLD
OFF ON ISSUANCE FOR NOW...PENDING ADDITIONAL SUPPORT FROM FORECAST
SOUNDINGS. WITH PARTIAL SUNSHINE AND STRONG WAA...HIGH TEMPS WILL
SOAR INTO THE UPPER 70S AND LOWER 80S.
TRAILING COLD FRONT WILL APPROACH FROM THE WEST BY LATE SUNDAY
AFTERNOON...ACCOMPANIED BY A BROKEN LINE OF THUNDERSTORMS. WHILE
BEST UPPER SUPPORT WILL SLIDE BY TO THE N/NW AND GREATEST
INSTABILITY WILL REMAIN TO THE S/SW...THINK POTENT MID/LOW-LEVEL
JETS WILL BE ENOUGH TO SUPPORT STRONG STORMS CAPABLE OF DAMAGING
WIND GUSTS. FORECAST SOUNDINGS INDICATE 0-3KM STORM RELATIVE
HELICITY VALUES INCREASING TO 400 TO 500 BY 00Z MON...WITH MOST OF
THIS INCREASE DUE TO SPEED SHEAR. ANY STORMS THAT FIRE IN THIS
ENVIRONMENT WILL BE FAST-MOVING AND CAPABLE OF BRINGING DAMAGING
WIND GUSTS DOWN TO THE SURFACE. MODEL CONSENSUS TRACKS LINE OF
STORMS INTO THE ILLINOIS RIVER VALLEY AFTER 21Z...THEN INTO
EAST-CENTRAL ILLINOIS AFTER 06Z.
FRONT AND ASSOCIATED STORMS WILL EXIT CENTRAL ILLINOIS LATE SUNDAY
NIGHT...FOLLOWED BY WINDY AND COOLER WEATHER ON MONDAY. TIGHT
PRESSURE GRADIENT ON THE BACK SIDE OF THE DEPARTING SYSTEM WILL
SUPPORT W/NW WINDS GUSTING UP TO 30 MPH...WHILE HIGH TEMPS DROP
BACK INTO THE 60S.
LONG TERM...TUESDAY THROUGH FRIDAY
ZONAL UPPER FLOW PATTERN WILL BE IN PLACE THROUGH THE
EXTENDED...ALLOWING A SERIES OF FAST-MOVING STORM SYSTEMS TO PASS
THROUGH THE REGION. A RATHER WEAK IMPULSE WILL TRACK THROUGH THE
UPPER MIDWEST INTO THE GREAT LAKES ON WEDNESDAY...HOWEVER BEST
LIFT WILL REMAIN WELL TO THE NORTH AND DEEP MOISTURE WILL BE
LACKING. AS A RESULT...HAVE ONLY INCLUDED SLIGHT CHANCE POPS
WEDNESDAY/WEDNESDAY NIGHT AS A WEAK BOUNDARY SLIDES THROUGH. BOTH
THE GFS AND ECMWF CONTINUE TO INDICATE A STRONGER WAVE APPROACHING
BY THE END OF THE WEEK...RESULTING IN A BETTER CHANCE FOR
SHOWERS/STORMS ON FRIDAY.
BARNES
&&
.AVIATION...
ISSUED 1150 PM CDT FRI APR 13 2012
ALL SITES WILL BE VFR TO START THE OVERNIGHT HOURS. THEN MVFR
CIGS AND VIS CAN BE EXPECTED ONCE PCPN AND LIGHT FOG BEGINS TO
AFFECT ALL SITES AFTER SUNRISE AND INTO THE MORNING HOURS.
IMPROVING CIGS AND VIS WILL NOT BE SEEN UNTIL AFTER THE WARM FRONT
LIFTS NORTHWARD PAST ALL TAF SITES DURING THE EARLY EVENING HOURS.
AN AREA OF PCPN IS MOVING EASTWARD TOWARD THE AREA...BUT APPEARS
IT COULD REMAIN SOUTH OF ALL TAF SITES. HOWEVER...SHORT TERM
MODELS CONTINUE TO FORECAST AN INCREASE IN COVERAGE OF SHOWERS AND
STORMS AS THE LOW LEVEL JET INTENSIFIES OVERNIGHT AND INTERACTS
WITH THE WARM FRONT IN NORTHERN MO. ONCE THIS OCCURS...ADDITIONAL
PCPN WILL MOVE INTO THE AREA. FOR NOW WILL START EVERYONE WITH
VCSH AFTER A COUPLE OF HOURS OF DRY WEATHER.
HOWEVER...SPI...DEC...CMI WILL SEE AN INCREASE OF PCPN/SHOWERS AND
THUNDERSTORMS DURING THE EARLY MORNING HOURS AS THE PCPN FROM
NORTHER MO MOVES EAST INTO THE AREA. EXPECTING SHOWERS AND
ISOLATED THUNDERSTORMS TO BEGIN AT SPI AROUND 11Z...DEC 12Z AND
CMI 13Z. DURING THIS TIME FRAME...PCPN SHOULD STAY SOUTH OF
PIA/BMI. AS THE WARM FRONT LIFTS NORTH DURING THE DAY...ADDITIONAL
RWS/TSTMS WILL BE ONGOING ALONG THE FRONT AND AFFECT ALL SITES
DURING THE AFTERNOON. PCPN WILL END AT PIS/DEC/CMI FIRST AROUND
01Z...FOLLOWED BY PIA/BMI AROUND 03Z. WINDS WILL BE SOUTHEAST THEN
SOUTHERLY AS THE WARM FRONT LIFTS NORTHWARD.
AUTEN
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1225 PM EDT SAT APR 14 2012
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 305 AM EDT SAT APR 14 2012
A WARM FRONT WILL MOVE THROUGH THE AREA LATER TODAY INTO
TONIGHT...BRINGING SHOWERS AND THUNDERSTORMS TO CENTRAL INDIANA. A
COLD FRONT WILL THEN MOVE THROUGH SUNDAY NIGHT INTO
MONDAY...BRINGING ANOTHER ROUND OF RAIN. DRY WEATHER WILL THEN
CONTINUE UNTIL LATE NEXT WEEK...WHEN ANOTHER FRONT BRINGS A CHANCE
FOR RAIN.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1018 AM EDT SAT APR 14 2012
RADAR LOOPS SHOW ANOTHER AREA OF SHOWERS AND THUNDERSTORMS WILL BE
SPREADING EAST ACROSS OUR AREA AND RAPID REFRESH SHOWS NUMEROUS
SHOWERS AND THUNDERSTORMS OCCURRING MOST OF TODAY. OVERALL CURRENT
FORECAST SEEMS TO BE ON TRACK AND I DID NOT MAKE ANY CHANGES FOR
CENTRAL AND NORTHERN SECTIONS OTHER THAN LOWERING WIND SPEEDS
SLIGHTLY.
THE 12Z RUC INDICATES TEMPERATURES IN THE 70S MAY NOT SPREAD MUCH
PAST OUR EXTREME SOUTH AND I WILL LOWER TEMPERATURES JUST A BIT
ACROSS THE SOUTH. THE PRECIP AND CLOUDS SHOULD LIMIT AMOUNT OF
MIXING AND WILL LOWER WIND SPEEDS ALL AREAS JUST A BIT.
PREVIOUS NEAR TERM DISCUSSION FOLLOWS...SEVERAL AREAS OF SHOWERS AND
THUNDERSTORMS EXIST AT THE MOMENT FROM ILLINOIS BACK TO KANSAS AND
OKLAHOMA. AT THE MOMENT THE MODEL THAT IS REFLECTING THE CURRENT
RADAR BEST IS THE HRRR. LEANED TOWARD ITS SOLUTION TODAY IN REGARDS
TO POPS.
A WARM FRONT WILL MOVE ACROSS THE AREA LATER TODAY...PROVIDING LIFT
ALONG AND WELL AHEAD OF THE FRONT. UPPER IMPULSES WILL PROVIDE
SUPPORT TO THE LIFT ALREADY BEING GENERATED BY THE WARM FRONT.
THE LIFT PLUS MOISTURE BEING PULLED NORTH INTO THE AREA SHOULD LEAD
TO PERIODS OF SHOWERS AND THUNDERSTORMS ACROSS THE ENTIRE AREA
TODAY. MOS POPS AND THE HRRR FORECAST AGREE WITH THIS...SO FEEL NO
NEED TO CUT MOS POPS. WILL GO CATEGORICAL POPS NEARLY THE ENTIRE
AREA.
INSTABILITY PARAMETERS AND SPC FORECAST AGREE THAT SEVERE STORMS
SHOULD NOT OCCUR TODAY.
WITH THE RAIN ACROSS THE AREA TODAY AND A LATER ARRIVAL OF THE WARM
FRONT...WENT AHEAD AND TRIMMED BACK HIGHS TODAY FROM PREVIOUS
FORECAST. GENERALLY WENT BETWEEN THE COOLER MET AND WARMER MAV.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
ISSUED AT 305 AM EDT SAT APR 14 2012
FOCUS IS ON CHANCES FOR RAIN INTO MONDAY. MODELS ARE GENERALLY CLOSE
ENOUGH THAT A BLEND CAN BE USED.
THE WARM FRONT WILL BE ON ITS WAY NORTH OF THE AREA THIS EVENING.
KEPT LOW END LIKELY POPS ACROSS THE NORTHERN THIRD OF THE AREA WITH
CHANCE OR SLIGHT CHANCE POPS TO THE SOUTH. FOR THE OVERNIGHT PERIOD
WENT LOW POPS ACROSS THE FAR NORTHERN FORECAST AREA TO ACCOUNT FOR
ANY LINGERING RAIN. WENT ABOVE MOS FOR TEMPERATURES WITH SOUTHERLY
WINDS OVERNIGHT IN THE WARM SECTOR.
REMOVED ALL POPS FOR SUNDAY AS THE FORECAST AREA WILL BE IN THE WARM
SECTOR OF THE SYSTEM...AND THERE WILL NOT BE ANY FORCING IN THE
AREA. WITH SOME SUNSHINE AND WARM ADVECTION...WENT ABOVE MOS FOR
HIGHS. SUNDAY WILL ALSO BE WINDY AS STRONGER WINDS ALOFT MIX DOWN TO
PRODUCE GUSTS OVER 30 MPH.
THE COLD FRONT WILL MOVE INTO THE AREA SUNDAY NIGHT. DECENT FLOW AT
THE SURFACE AND ALOFT SHOULD BRING IN ENOUGH MOISTURE TO INTERACT
WITH THE FRONT FOR LIKELY OR HIGHER POPS MOST AREAS BY THE END OF
THE NIGHT.
THE FRONT WILL STILL BE CROSSING THE AREA EARLY MONDAY...AND BASED
ON EXPECTED TIMING WENT LIKELY POPS EXTREME EAST TO SLIGHT CHANCE
POPS EXTREME WEST DURING THE MORNING. DURING THE AFTERNOON ONLY WENT
SLIGHT CHANCE POPS ACROSS THE FAR SOUTHEAST AS THE FRONT SHOULD HAVE
TAKEN MOST OF THE RAIN WITH IT AS IT HEADS EAST OF THE AREA.
MONDAY NIGHT WILL BE DRY AND COOLER AS HIGH PRESSURE MOVES IN.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
ISSUED AT 305 AM EDT SAT APR 14 2012
EXTENDED PERIOD WILL START WITH DRY AND SEASONABLY COOL WEATHER AS
HIGH PRESSURE RIDGE DRIFTS ACROSS THE REGION. HIGHS WILL LARGELY
REMAIN IN THE 60S TUESDAY AND WEDNESDAY WITH RETURN SOUTHERLY FLOW
DEVELOPING BY LATE DAY AS THE HIGH MOVES EAST. LOW PRESSURE SET TO
TRACK INTO THE GREAT LAKES WEDNESDAY NIGHT WITH A WEAK FRONTAL
BOUNDARY SAGGING INTO CENTRAL INDIANA. MODEL CONSENSUS CONTINUES TO
LIMIT MOISTURE AND FORCING ALOFT ACROSS THE REGION...FOCUSING THE
BETTER LIFT FURTHER NORTH IN CLOSER PROXIMITY TO THE LOW. WILL
MAINTAIN LOW CHANCE POPS OVER FAR NORTHERN COUNTIES TO ACCOUNT FOR
ANY ISOLATED PRECIP THAT CAN MIGRATE INTO THE REGION WITH THE
BOUNDARY.
BOUNDARY WILL BECOME STALLED ACROSS THE REGION THURSDAY BEFORE
LIFTING BACK NORTH BY THURSDAY NIGHT IN RESPONSE TO A STRONGER WAVE
MOVING OUT OF THE CENTRAL PLAINS AND INTO THE MID MISSISSIPPI VALLEY
BY EARLY FRIDAY. EXTENDED MODELS IN GOOD AGREEMENT IN TRACKING THIS
WAVE AND THE ASSOCIATED COLD FRONT ACROSS THE FORECAST AREA ON
FRIDAY WITH WIDESPREAD RAIN AND THUNDERSTORMS. MAINTAINED HIGH
CHANCE POPS FOR FRIDAY AND FRIDAY NIGHT. TEMPERATURES LIKELY TO
RETURN TO THE 70S THURSDAY AND FRIDAY FOR MUCH OF THE FORECAST AREA
WITH SLIGHTLY COOLER TEMPERATURES BY SATURDAY IN WAKE OF THE FRONTAL
PASSAGE.
&&
.AVIATION /DISCUSSION FOR 141800Z TAF ISSUANCE/...
ISSUED AT 1206 PM EDT SAT APR 14 2012
PERIODIC THUNDERSTORMS WILL CONTINUE THROUGH THE REST OF TODAY WITH
MVFR CONDITIONS DEVELOPING. VFR CONDITIONS WILL RETURN BY TONIGHT.
WINDY SUNDAY.
LATEST RADAR MOSAIC SHOWS THE LATEST (3RD) WAVE OF SHOWERS AND
THUNDERSTORMS TO IMPACT CENTRAL INDIANA CURRENTLY MOVING ACROSS
THE AREA. HAVE TRENDED THE FIRST FEW HOURS OF THE TAF ISSUANCE
BASED ON THIS WAVE. MORE SCATTERED SHOWERS AND POSSIBLY A FEW
ISOLATED TSMTS WILL PREVAIL AFTERWARD THE WAVE MOVES THROUGH (19Z)
BEFORE THE NEXT WAVE MOVES THROUGH LATER THIS AFTERNOON. GENERAL
TREND IS FOR MFVR TO DEVELOP (OR HAVE DEVELOPED) WITH POSSIBLE IFR
IN ANY OF THE HEAVIER RAIN. THIS WILL HOLD UNTIL AFTER THE NEXT
WAVE MOVES ACROSS THE AREA AND THEN LOOK FOR GRADUALLY IMPROVING
FLIGHT CONDITIONS TONIGHT...WITH KLAF THE LAST TO IMPROVE TO VFR.
CONVECTION MORE SCATTERED DURING THE EVENING HOURS AND EVENTUALLY
LIFTS NORTH OF ALL THE TERMINALS AFTER MIDNIGHT AS THE WARM FRONT
MOVES INTO NORTHERN INDIANA. HAVE MAINTAINED A VCSH MENTION
THROUGH THE EVENING WITH MVFR CEILINGS...WITH VFR CONDITIONS
ANTICIPATED FROM LATE EVENING THROUGH THE REST OF THE NIGHT.
NEXT PROBLEM IN THE FORECAST IS THE WINDS FOR SUNDAY. WINDS BEGIN
TO PICK UP AT THE SURFACE BY SUNDAY MORNING AND GUST TO 30-32 KT
DURING THE AFTERNOON.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...50
NEAR TERM...50/JH
SHORT TERM...50
LONG TERM....RYAN
AVIATION...SMF
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1022 AM EDT SAT APR 14 2012
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 305 AM EDT SAT APR 14 2012
A WARM FRONT WILL MOVE THROUGH THE AREA LATER TODAY INTO
TONIGHT...BRINGING SHOWERS AND THUNDERSTORMS TO CENTRAL INDIANA. A
COLD FRONT WILL THEN MOVE THROUGH SUNDAY NIGHT INTO
MONDAY...BRINGING ANOTHER ROUND OF RAIN. DRY WEATHER WILL THEN
CONTINUE UNTIL LATE NEXT WEEK...WHEN ANOTHER FRONT BRINGS A CHANCE
FOR RAIN.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1018 AM EDT SAT APR 14 2012
RADAR LOOPS SHOW ANOTHER AREA OF SHOWERS AND THUNDERSTORMS WILL BE
SPREADING EAST ACROSS OUR AREA AND RAPID REFRESH SHOWS NUMEROUS
SHOWERS AND THUNDERSTORMS OCCURRING MOST OF TODAY. OVERALL CURRENT
FORECAST SEEMS TO BE ON TRACK AND I DID NOT MAKE ANY CHANGES FOR
CENTRAL AND NORTHERN SECTIONS OTHER THAN LOWERING WIND SPEEDS
SLIGHTLY.
THE 12Z RUC INDICATES TEMPERATURES IN THE 70S MAY NOT SPREAD MUCH
PAST OUR EXTREME SOUTH AND I WILL LOWER TEMPERATURES JUST A BIT
ACROSS THE SOUTH. THE PRECIP AND CLOUDS SHOULD LIMIT AMOUNT OF
MIXING AND WILL LOWER WIND SPEEDS ALL AREAS JUST A BIT.
PREVIOUS NEAR TERM DISCUSSION FOLLOWS...SEVERAL AREAS OF SHOWERS AND
THUNDERSTORMS EXIST AT THE MOMENT FROM ILLINOIS BACK TO KANSAS AND
OKLAHOMA. AT THE MOMENT THE MODEL THAT IS REFLECTING THE CURRENT
RADAR BEST IS THE HRRR. LEANED TOWARD ITS SOLUTION TODAY IN REGARDS
TO POPS.
A WARM FRONT WILL MOVE ACROSS THE AREA LATER TODAY...PROVIDING LIFT
ALONG AND WELL AHEAD OF THE FRONT. UPPER IMPULSES WILL PROVIDE
SUPPORT TO THE LIFT ALREADY BEING GENERATED BY THE WARM FRONT.
THE LIFT PLUS MOISTURE BEING PULLED NORTH INTO THE AREA SHOULD LEAD
TO PERIODS OF SHOWERS AND THUNDERSTORMS ACROSS THE ENTIRE AREA
TODAY. MOS POPS AND THE HRRR FORECAST AGREE WITH THIS...SO FEEL NO
NEED TO CUT MOS POPS. WILL GO CATEGORICAL POPS NEARLY THE ENTIRE
AREA.
INSTABILITY PARAMETERS AND SPC FORECAST AGREE THAT SEVERE STORMS
SHOULD NOT OCCUR TODAY.
WITH THE RAIN ACROSS THE AREA TODAY AND A LATER ARRIVAL OF THE WARM
FRONT...WENT AHEAD AND TRIMMED BACK HIGHS TODAY FROM PREVIOUS
FORECAST. GENERALLY WENT BETWEEN THE COOLER MET AND WARMER MAV.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
ISSUED AT 305 AM EDT SAT APR 14 2012
FOCUS IS ON CHANCES FOR RAIN INTO MONDAY. MODELS ARE GENERALLY CLOSE
ENOUGH THAT A BLEND CAN BE USED.
THE WARM FRONT WILL BE ON ITS WAY NORTH OF THE AREA THIS EVENING.
KEPT LOW END LIKELY POPS ACROSS THE NORTHERN THIRD OF THE AREA WITH
CHANCE OR SLIGHT CHANCE POPS TO THE SOUTH. FOR THE OVERNIGHT PERIOD
WENT LOW POPS ACROSS THE FAR NORTHERN FORECAST AREA TO ACCOUNT FOR
ANY LINGERING RAIN. WENT ABOVE MOS FOR TEMPERATURES WITH SOUTHERLY
WINDS OVERNIGHT IN THE WARM SECTOR.
REMOVED ALL POPS FOR SUNDAY AS THE FORECAST AREA WILL BE IN THE WARM
SECTOR OF THE SYSTEM...AND THERE WILL NOT BE ANY FORCING IN THE
AREA. WITH SOME SUNSHINE AND WARM ADVECTION...WENT ABOVE MOS FOR
HIGHS. SUNDAY WILL ALSO BE WINDY AS STRONGER WINDS ALOFT MIX DOWN TO
PRODUCE GUSTS OVER 30 MPH.
THE COLD FRONT WILL MOVE INTO THE AREA SUNDAY NIGHT. DECENT FLOW AT
THE SURFACE AND ALOFT SHOULD BRING IN ENOUGH MOISTURE TO INTERACT
WITH THE FRONT FOR LIKELY OR HIGHER POPS MOST AREAS BY THE END OF
THE NIGHT.
THE FRONT WILL STILL BE CROSSING THE AREA EARLY MONDAY...AND BASED
ON EXPECTED TIMING WENT LIKELY POPS EXTREME EAST TO SLIGHT CHANCE
POPS EXTREME WEST DURING THE MORNING. DURING THE AFTERNOON ONLY WENT
SLIGHT CHANCE POPS ACROSS THE FAR SOUTHEAST AS THE FRONT SHOULD HAVE
TAKEN MOST OF THE RAIN WITH IT AS IT HEADS EAST OF THE AREA.
MONDAY NIGHT WILL BE DRY AND COOLER AS HIGH PRESSURE MOVES IN.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
ISSUED AT 305 AM EDT SAT APR 14 2012
EXTENDED PERIOD WILL START WITH DRY AND SEASONABLY COOL WEATHER AS
HIGH PRESSURE RIDGE DRIFTS ACROSS THE REGION. HIGHS WILL LARGELY
REMAIN IN THE 60S TUESDAY AND WEDNESDAY WITH RETURN SOUTHERLY FLOW
DEVELOPING BY LATE DAY AS THE HIGH MOVES EAST. LOW PRESSURE SET TO
TRACK INTO THE GREAT LAKES WEDNESDAY NIGHT WITH A WEAK FRONTAL
BOUNDARY SAGGING INTO CENTRAL INDIANA. MODEL CONSENSUS CONTINUES TO
LIMIT MOISTURE AND FORCING ALOFT ACROSS THE REGION...FOCUSING THE
BETTER LIFT FURTHER NORTH IN CLOSER PROXIMITY TO THE LOW. WILL
MAINTAIN LOW CHANCE POPS OVER FAR NORTHERN COUNTIES TO ACCOUNT FOR
ANY ISOLATED PRECIP THAT CAN MIGRATE INTO THE REGION WITH THE
BOUNDARY.
BOUNDARY WILL BECOME STALLED ACROSS THE REGION THURSDAY BEFORE
LIFTING BACK NORTH BY THURSDAY NIGHT IN RESPONSE TO A STRONGER WAVE
MOVING OUT OF THE CENTRAL PLAINS AND INTO THE MID MISSISSIPPI VALLEY
BY EARLY FRIDAY. EXTENDED MODELS IN GOOD AGREEMENT IN TRACKING THIS
WAVE AND THE ASSOCIATED COLD FRONT ACROSS THE FORECAST AREA ON
FRIDAY WITH WIDESPREAD RAIN AND THUNDERSTORMS. MAINTAINED HIGH
CHANCE POPS FOR FRIDAY AND FRIDAY NIGHT. TEMPERATURES LIKELY TO
RETURN TO THE 70S THURSDAY AND FRIDAY FOR MUCH OF THE FORECAST AREA
WITH SLIGHTLY COOLER TEMPERATURES BY SATURDAY IN WAKE OF THE FRONTAL
PASSAGE.
&&
.AVIATION /DISCUSSION FOR 141200Z TAF ISSUANCE/...
ISSUED AT 1020 AM EDT SAT APR 14 2012
1030Z UPDATE...ADDED A TEMPO GROUP FOR IFR CEILINGS BASED ON
TRENDS PAST 2 HOURS. NEXT ROUND OF SHOWERS AND TSTMS DUE INTO
CENTRAL AROUND 16Z SO WENT DRY IN THE PREVAILING AND KEPT THUNDER
IN FOR 16Z. NO OTHER CHANGES WERE MADE AT THIS TIME. PREV DISC
FOLLOWS...
ISSUED AT 702 AM EDT SAT APR 14 2012
THUNDERSTORMS LIKELY THROUGH THE DAY WITH MVFR CONDITIONS
DEVELOPING FOR THE AFTERNOON. VFR CONDITIONS RETURNING TONIGHT.
AREA OF RAIN WITH EMBEDDED THUNDERSTORMS HOLDING TOGETHER OVER THE
LOWER WABASH VALLEY EARLY THIS MORNING AND WILL IMPACT KBMG...KHUF
AND KIND FOR THE FIRST FEW HOURS WITH POTENTIAL FOR BRIEF DROPS TO
MVFR VISIBILITIES. A MORE SUBSTANTIAL AREA OF THUNDERSTORMS OVER
CENTRAL MISSOURI WILL LIFT NORTHEAST AND ARRIVE IN THE FORECAST
AREA BY LATE MORNING. WILL CONTINUE WITH PREVAILING THUNDER AT ALL
TERMINALS AFTER 15-16Z AND PERSISTING FOR MUCH OF THE REST OF THE
DAYLIGHT HOURS. HRRR CONTINUING TO ADVERTISE SEVERAL WAVES OF
CONVECTION LIFTING INTO THE REGION AHEAD OF THE APPROACHING WARM
FRONT THROUGH THE AFTERNOON. WHILE ITS NOT LIKELY TO RAIN THE
ENTIRE AFTERNOON...FELT PREVAILING THUNDER WAS THE BEST WAY TO
HANDLE EXPECTED WIDESPREAD CONVECTIVE COVERAGE OVER CENTRAL
INDIANA. MODEL SOUNDINGS AND LOW LEVEL RH PROGS FAVOR LOWER
CEILINGS BETWEEN 1000-2000FT DEVELOPING FOR MUCH OF THE AFTERNOON
AS WELL. S/SW WINDS AT 10-15KTS EXPECTED.
CONVECTION WILL BECOME MORE SCATTERED DURING THE EVENING HOURS AND
EVENTUALLY LIFT NORTH OF THE TERMINALS AFTER MIDNIGHT AS THE WARM
FRONT MOVES INTO NORTHERN INDIANA. HAVE MAINTAINED A VCSH MENTION
THROUGH THE EVENING WITH MVFR CEILINGS...WITH VFR CONDITIONS
ANTICIPATED FROM LATE EVENING THROUGH THE REST OF THE NIGHT.
SOUTHERLY WINDS WILL REMAIN AT NEAR 10KTS OVERNIGHT.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...50
NEAR TERM...50/JH
SHORT TERM...50
LONG TERM....RYAN
AVIATION...RYAN/SMF
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1018 AM EDT SAT APR 14 2012
.UPDATE...
NEAR TERM SECTION FOR THE REST OF TODAY HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 305 AM EDT SAT APR 14 2012
A WARM FRONT WILL MOVE THROUGH THE AREA LATER TODAY INTO
TONIGHT...BRINGING SHOWERS AND THUNDERSTORMS TO CENTRAL INDIANA. A
COLD FRONT WILL THEN MOVE THROUGH SUNDAY NIGHT INTO
MONDAY...BRINGING ANOTHER ROUND OF RAIN. DRY WEATHER WILL THEN
CONTINUE UNTIL LATE NEXT WEEK...WHEN ANOTHER FRONT BRINGS A CHANCE
FOR RAIN.
&&
.NEAR TERM /REST OF TODAY/...
ISSUED AT 1018 AM EDT SAT APR 14 2012
RADAR LOOPS SHOW ANOTHER AREA OF SHOWERS AND THUNDERSTORMS WILL BE
SPREADING EAST ACROSS OUR AREA AND RAPID REFRESH SHOWS NUMEROUS
SHOWERS AND THUNDERSTORMS OCCURRING MOST OF TODAY. OVERALL CURRENT
FORECAST SEEMS TO BE ON TRACK AND I DID NOT MAKE ANY CHANGES FOR
CENTRAL AND NORTHERN SECTIONS OTHER THAN LOWERING WIND SPEEDS
SLIGHTLY.
THE 12Z RUC INDICATES TEMPERATURES IN THE 70S MAY NOT SPREAD MUCH
PAST OUR EXTREME SOUTH AND I WILL LOWER TEMPERATURES JUST A BIT
ACROSS THE SOUTH. THE PRECIP AND CLOUDS SHOULD LIMIT AMOUNT OF
MIXING AND WILL LOWER WIND SPEEDS ALL AREAS JUST A BIT.
PREVIOUS NEAR TERM DISCUSSION FOLLOWS...SEVERAL AREAS OF SHOWERS AND
THUNDERSTORMS EXIST AT THE MOMENT FROM ILLINOIS BACK TO KANSAS AND
OKLAHOMA. AT THE MOMENT THE MODEL THAT IS REFLECTING THE CURRENT
RADAR BEST IS THE HRRR. LEANED TOWARD ITS SOLUTION TODAY IN REGARDS
TO POPS.
A WARM FRONT WILL MOVE ACROSS THE AREA LATER TODAY...PROVIDING LIFT
ALONG AND WELL AHEAD OF THE FRONT. UPPER IMPULSES WILL PROVIDE
SUPPORT TO THE LIFT ALREADY BEING GENERATED BY THE WARM FRONT.
THE LIFT PLUS MOISTURE BEING PULLED NORTH INTO THE AREA SHOULD LEAD
TO PERIODS OF SHOWERS AND THUNDERSTORMS ACROSS THE ENTIRE AREA
TODAY. MOS POPS AND THE HRRR FORECAST AGREE WITH THIS...SO FEEL NO
NEED TO CUT MOS POPS. WILL GO CATEGORICAL POPS NEARLY THE ENTIRE
AREA.
INSTABILITY PARAMETERS AND SPC FORECAST AGREE THAT SEVERE STORMS
SHOULD NOT OCCUR TODAY.
WITH THE RAIN ACROSS THE AREA TODAY AND A LATER ARRIVAL OF THE WARM
FRONT...WENT AHEAD AND TRIMMED BACK HIGHS TODAY FROM PREVIOUS
FORECAST. GENERALLY WENT BETWEEN THE COOLER MET AND WARMER MAV.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
ISSUED AT 305 AM EDT SAT APR 14 2012
FOCUS IS ON CHANCES FOR RAIN INTO MONDAY. MODELS ARE GENERALLY CLOSE
ENOUGH THAT A BLEND CAN BE USED.
THE WARM FRONT WILL BE ON ITS WAY NORTH OF THE AREA THIS EVENING.
KEPT LOW END LIKELY POPS ACROSS THE NORTHERN THIRD OF THE AREA WITH
CHANCE OR SLIGHT CHANCE POPS TO THE SOUTH. FOR THE OVERNIGHT PERIOD
WENT LOW POPS ACROSS THE FAR NORTHERN FORECAST AREA TO ACCOUNT FOR
ANY LINGERING RAIN. WENT ABOVE MOS FOR TEMPERATURES WITH SOUTHERLY
WINDS OVERNIGHT IN THE WARM SECTOR.
REMOVED ALL POPS FOR SUNDAY AS THE FORECAST AREA WILL BE IN THE WARM
SECTOR OF THE SYSTEM...AND THERE WILL NOT BE ANY FORCING IN THE
AREA. WITH SOME SUNSHINE AND WARM ADVECTION...WENT ABOVE MOS FOR
HIGHS. SUNDAY WILL ALSO BE WINDY AS STRONGER WINDS ALOFT MIX DOWN TO
PRODUCE GUSTS OVER 30 MPH.
THE COLD FRONT WILL MOVE INTO THE AREA SUNDAY NIGHT. DECENT FLOW AT
THE SURFACE AND ALOFT SHOULD BRING IN ENOUGH MOISTURE TO INTERACT
WITH THE FRONT FOR LIKELY OR HIGHER POPS MOST AREAS BY THE END OF
THE NIGHT.
THE FRONT WILL STILL BE CROSSING THE AREA EARLY MONDAY...AND BASED
ON EXPECTED TIMING WENT LIKELY POPS EXTREME EAST TO SLIGHT CHANCE
POPS EXTREME WEST DURING THE MORNING. DURING THE AFTERNOON ONLY WENT
SLIGHT CHANCE POPS ACROSS THE FAR SOUTHEAST AS THE FRONT SHOULD HAVE
TAKEN MOST OF THE RAIN WITH IT AS IT HEADS EAST OF THE AREA.
MONDAY NIGHT WILL BE DRY AND COOLER AS HIGH PRESSURE MOVES IN.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
ISSUED AT 305 AM EDT SAT APR 14 2012
EXTENDED PERIOD WILL START WITH DRY AND SEASONABLY COOL WEATHER AS
HIGH PRESSURE RIDGE DRIFTS ACROSS THE REGION. HIGHS WILL LARGELY
REMAIN IN THE 60S TUESDAY AND WEDNESDAY WITH RETURN SOUTHERLY FLOW
DEVELOPING BY LATE DAY AS THE HIGH MOVES EAST. LOW PRESSURE SET TO
TRACK INTO THE GREAT LAKES WEDNESDAY NIGHT WITH A WEAK FRONTAL
BOUNDARY SAGGING INTO CENTRAL INDIANA. MODEL CONSENSUS CONTINUES TO
LIMIT MOISTURE AND FORCING ALOFT ACROSS THE REGION...FOCUSING THE
BETTER LIFT FURTHER NORTH IN CLOSER PROXIMITY TO THE LOW. WILL
MAINTAIN LOW CHANCE POPS OVER FAR NORTHERN COUNTIES TO ACCOUNT FOR
ANY ISOLATED PRECIP THAT CAN MIGRATE INTO THE REGION WITH THE
BOUNDARY.
BOUNDARY WILL BECOME STALLED ACROSS THE REGION THURSDAY BEFORE
LIFTING BACK NORTH BY THURSDAY NIGHT IN RESPONSE TO A STRONGER WAVE
MOVING OUT OF THE CENTRAL PLAINS AND INTO THE MID MISSISSIPPI VALLEY
BY EARLY FRIDAY. EXTENDED MODELS IN GOOD AGREEMENT IN TRACKING THIS
WAVE AND THE ASSOCIATED COLD FRONT ACROSS THE FORECAST AREA ON
FRIDAY WITH WIDESPREAD RAIN AND THUNDERSTORMS. MAINTAINED HIGH
CHANCE POPS FOR FRIDAY AND FRIDAY NIGHT. TEMPERATURES LIKELY TO
RETURN TO THE 70S THURSDAY AND FRIDAY FOR MUCH OF THE FORECAST AREA
WITH SLIGHTLY COOLER TEMPERATURES BY SATURDAY IN WAKE OF THE FRONTAL
PASSAGE.
&&
.AVIATION /DISCUSSION FOR 141200Z TAF ISSUANCE/...
ISSUED AT 702 AM EDT SAT APR 14 2012
THUNDERSTORMS LIKELY THROUGH THE DAY WITH MVFR CONDITIONS
DEVELOPING FOR THE AFTERNOON. VFR CONDITIONS RETURNING TONIGHT.
AREA OF RAIN WITH EMBEDDED THUNDERSTORMS HOLDING TOGETHER OVER THE
LOWER WABASH VALLEY EARLY THIS MORNING AND WILL IMPACT KBMG...KHUF
AND KIND FOR THE FIRST FEW HOURS WITH POTENTIAL FOR BRIEF DROPS TO
MVFR VISIBILITIES. A MORE SUBSTANTIAL AREA OF THUNDERSTORMS OVER
CENTRAL MISSOURI WILL LIFT NORTHEAST AND ARRIVE IN THE FORECAST
AREA BY LATE MORNING. WILL CONTINUE WITH PREVAILING THUNDER AT ALL
TERMINALS AFTER 15-16Z AND PERSISTING FOR MUCH OF THE REST OF THE
DAYLIGHT HOURS. HRRR CONTINUING TO ADVERTISE SEVERAL WAVES OF
CONVECTION LIFTING INTO THE REGION AHEAD OF THE APPROACHING WARM
FRONT THROUGH THE AFTERNOON. WHILE ITS NOT LIKELY TO RAIN THE
ENTIRE AFTERNOON...FELT PREVAILING THUNDER WAS THE BEST WAY TO
HANDLE EXPECTED WIDESPREAD CONVECTIVE COVERAGE OVER CENTRAL
INDIANA. MODEL SOUNDINGS AND LOW LEVEL RH PROGS FAVOR LOWER
CEILINGS BETWEEN 1000-2000FT DEVELOPING FOR MUCH OF THE AFTERNOON
AS WELL. S/SW WINDS AT 10-15KTS EXPECTED.
CONVECTION WILL BECOME MORE SCATTERED DURING THE EVENING HOURS AND
EVENTUALLY LIFT NORTH OF THE TERMINALS AFTER MIDNIGHT AS THE WARM
FRONT MOVES INTO NORTHERN INDIANA. HAVE MAINTAINED A VCSH MENTION
THROUGH THE EVENING WITH MVFR CEILINGS...WITH VFR CONDITIONS
ANTICIPATED FROM LATE EVENING THROUGH THE REST OF THE NIGHT.
SOUTHERLY WINDS WILL REMAIN AT NEAR 10KTS OVERNIGHT.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...50
NEAR TERM...50/JH
SHORT TERM...50
LONG TERM....RYAN
AVIATION...RYAN
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
702 AM EDT SAT APR 14 2012
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 305 AM EDT SAT APR 14 2012
A WARM FRONT WILL MOVE THROUGH THE AREA LATER TODAY INTO
TONIGHT...BRINGING SHOWERS AND THUNDERSTORMS TO CENTRAL INDIANA. A
COLD FRONT WILL THEN MOVE THROUGH SUNDAY NIGHT INTO
MONDAY...BRINGING ANOTHER ROUND OF RAIN. DRY WEATHER WILL THEN
CONTINUE UNTIL LATE NEXT WEEK...WHEN ANOTHER FRONT BRINGS A CHANCE
FOR RAIN.
&&
.NEAR TERM /TODAY/...
ISSUED AT 305 AM EDT SAT APR 14 2012
SEVERAL AREAS OF SHOWERS AND THUNDERSTORMS EXIST AT THE MOMENT FROM
ILLINOIS BACK TO KANSAS AND OKLAHOMA. AT THE MOMENT THE MODEL THAT
IS REFLECTING THE CURRENT RADAR BEST IS THE HRRR. LEANED TOWARD ITS
SOLUTION TODAY IN REGARDS TO POPS.
A WARM FRONT WILL MOVE ACROSS THE AREA LATER TODAY...PROVIDING LIFT
ALONG AND WELL AHEAD OF THE FRONT. UPPER IMPULSES WILL PROVIDE
SUPPORT TO THE LIFT ALREADY BEING GENERATED BY THE WARM FRONT.
THE LIFT PLUS MOISTURE BEING PULLED NORTH INTO THE AREA SHOULD LEAD
TO PERIODS OF SHOWERS AND THUNDERSTORMS ACROSS THE ENTIRE AREA
TODAY. MOS POPS AND THE HRRR FORECAST AGREE WITH THIS...SO FEEL NO
NEED TO CUT MOS POPS. WILL GO CATEGORICAL POPS NEARLY THE ENTIRE
AREA.
INSTABILITY PARAMETERS AND SPC FORECAST AGREE THAT SEVERE STORMS
SHOULD NOT OCCUR TODAY.
WITH THE RAIN ACROSS THE AREA TODAY AND A LATER ARRIVAL OF THE WARM
FRONT...WENT AHEAD AND TRIMMED BACK HIGHS TODAY FROM PREVIOUS
FORECAST. GENERALLY WENT BETWEEN THE COOLER MET AND WARMER MAV.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
ISSUED AT 305 AM EDT SAT APR 14 2012
FOCUS IS ON CHANCES FOR RAIN INTO MONDAY. MODELS ARE GENERALLY CLOSE
ENOUGH THAT A BLEND CAN BE USED.
THE WARM FRONT WILL BE ON ITS WAY NORTH OF THE AREA THIS EVENING.
KEPT LOW END LIKELY POPS ACROSS THE NORTHERN THIRD OF THE AREA WITH
CHANCE OR SLIGHT CHANCE POPS TO THE SOUTH. FOR THE OVERNIGHT PERIOD
WENT LOW POPS ACROSS THE FAR NORTHERN FORECAST AREA TO ACCOUNT FOR
ANY LINGERING RAIN. WENT ABOVE MOS FOR TEMPERATURES WITH SOUTHERLY
WINDS OVERNIGHT IN THE WARM SECTOR.
REMOVED ALL POPS FOR SUNDAY AS THE FORECAST AREA WILL BE IN THE WARM
SECTOR OF THE SYSTEM...AND THERE WILL NOT BE ANY FORCING IN THE
AREA. WITH SOME SUNSHINE AND WARM ADVECTION...WENT ABOVE MOS FOR
HIGHS. SUNDAY WILL ALSO BE WINDY AS STRONGER WINDS ALOFT MIX DOWN TO
PRODUCE GUSTS OVER 30 MPH.
THE COLD FRONT WILL MOVE INTO THE AREA SUNDAY NIGHT. DECENT FLOW AT
THE SURFACE AND ALOFT SHOULD BRING IN ENOUGH MOISTURE TO INTERACT
WITH THE FRONT FOR LIKELY OR HIGHER POPS MOST AREAS BY THE END OF
THE NIGHT.
THE FRONT WILL STILL BE CROSSING THE AREA EARLY MONDAY...AND BASED
ON EXPECTED TIMING WENT LIKELY POPS EXTREME EAST TO SLIGHT CHANCE
POPS EXTREME WEST DURING THE MORNING. DURING THE AFTERNOON ONLY WENT
SLIGHT CHANCE POPS ACROSS THE FAR SOUTHEAST AS THE FRONT SHOULD HAVE
TAKEN MOST OF THE RAIN WITH IT AS IT HEADS EAST OF THE AREA.
MONDAY NIGHT WILL BE DRY AND COOLER AS HIGH PRESSURE MOVES IN.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
ISSUED AT 305 AM EDT SAT APR 14 2012
EXTENDED PERIOD WILL START WITH DRY AND SEASONABLY COOL WEATHER AS
HIGH PRESSURE RIDGE DRIFTS ACROSS THE REGION. HIGHS WILL LARGELY
REMAIN IN THE 60S TUESDAY AND WEDNESDAY WITH RETURN SOUTHERLY FLOW
DEVELOPING BY LATE DAY AS THE HIGH MOVES EAST. LOW PRESSURE SET TO
TRACK INTO THE GREAT LAKES WEDNESDAY NIGHT WITH A WEAK FRONTAL
BOUNDARY SAGGING INTO CENTRAL INDIANA. MODEL CONSENSUS CONTINUES TO
LIMIT MOISTURE AND FORCING ALOFT ACROSS THE REGION...FOCUSING THE
BETTER LIFT FURTHER NORTH IN CLOSER PROXIMITY TO THE LOW. WILL
MAINTAIN LOW CHANCE POPS OVER FAR NORTHERN COUNTIES TO ACCOUNT FOR
ANY ISOLATED PRECIP THAT CAN MIGRATE INTO THE REGION WITH THE
BOUNDARY.
BOUNDARY WILL BECOME STALLED ACROSS THE REGION THURSDAY BEFORE
LIFTING BACK NORTH BY THURSDAY NIGHT IN RESPONSE TO A STRONGER WAVE
MOVING OUT OF THE CENTRAL PLAINS AND INTO THE MID MISSISSIPPI VALLEY
BY EARLY FRIDAY. EXTENDED MODELS IN GOOD AGREEMENT IN TRACKING THIS
WAVE AND THE ASSOCIATED COLD FRONT ACROSS THE FORECAST AREA ON
FRIDAY WITH WIDESPREAD RAIN AND THUNDERSTORMS. MAINTAINED HIGH
CHANCE POPS FOR FRIDAY AND FRIDAY NIGHT. TEMPERATURES LIKELY TO
RETURN TO THE 70S THURSDAY AND FRIDAY FOR MUCH OF THE FORECAST AREA
WITH SLIGHTLY COOLER TEMPERATURES BY SATURDAY IN WAKE OF THE FRONTAL
PASSAGE.
&&
.AVIATION /DISCUSSION FOR 141200Z TAF ISSUANCE/...
ISSUED AT 702 AM EDT SAT APR 14 2012
THUNDERSTORMS LIKELY THROUGH THE DAY WITH MVFR CONDITIONS
DEVELOPING FOR THE AFTERNOON. VFR CONDITIONS RETURNING TONIGHT.
AREA OF RAIN WITH EMBEDDED THUNDERSTORMS HOLDING TOGETHER OVER THE
LOWER WABASH VALLEY EARLY THIS MORNING AND WILL IMPACT KBMG...KHUF
AND KIND FOR THE FIRST FEW HOURS WITH POTENTIAL FOR BRIEF DROPS TO
MVFR VISIBILITIES. A MORE SUBSTANTIAL AREA OF THUNDERSTORMS OVER
CENTRAL MISSOURI WILL LIFT NORTHEAST AND ARRIVE IN THE FORECAST
AREA BY LATE MORNING. WILL CONTINUE WITH PREVAILING THUNDER AT ALL
TERMINALS AFTER 15-16Z AND PERSISTING FOR MUCH OF THE REST OF THE
DAYLIGHT HOURS. HRRR CONTINUING TO ADVERTISE SEVERAL WAVES OF
CONVECTION LIFTING INTO THE REGION AHEAD OF THE APPROACHING WARM
FRONT THROUGH THE AFTERNOON. WHILE ITS NOT LIKELY TO RAIN THE
ENTIRE AFTERNOON...FELT PREVAILING THUNDER WAS THE BEST WAY TO
HANDLE EXPECTED WIDESPREAD CONVECTIVE COVERAGE OVER CENTRAL
INDIANA. MODEL SOUNDINGS AND LOW LEVEL RH PROGS FAVOR LOWER
CEILINGS BETWEEN 1000-2000FT DEVELOPING FOR MUCH OF THE AFTERNOON
AS WELL. S/SW WINDS AT 10-15KTS EXPECTED.
CONVECTION WILL BECOME MORE SCATTERED DURING THE EVENING HOURS AND
EVENTUALLY LIFT NORTH OF THE TERMINALS AFTER MIDNIGHT AS THE WARM
FRONT MOVES INTO NORTHERN INDIANA. HAVE MAINTAINED A VCSH MENTION
THROUGH THE EVENING WITH MVFR CEILINGS...WITH VFR CONDITIONS
ANTICIPATED FROM LATE EVENING THROUGH THE REST OF THE NIGHT.
SOUTHERLY WINDS WILL REMAIN AT NEAR 10KTS OVERNIGHT.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...50
NEAR TERM...50
SHORT TERM...50
LONG TERM....RYAN
AVIATION...RYAN
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
429 AM EDT SAT APR 14 2012
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 305 AM EDT SAT APR 14 2012
A WARM FRONT WILL MOVE THROUGH THE AREA LATER TODAY INTO
TONIGHT...BRINGING SHOWERS AND THUNDERSTORMS TO CENTRAL INDIANA. A
COLD FRONT WILL THEN MOVE THROUGH SUNDAY NIGHT INTO
MONDAY...BRINGING ANOTHER ROUND OF RAIN. DRY WEATHER WILL THEN
CONTINUE UNTIL LATE NEXT WEEK...WHEN ANOTHER FRONT BRINGS A CHANCE
FOR RAIN.
&&
.NEAR TERM /TODAY/...
ISSUED AT 305 AM EDT SAT APR 14 2012
SEVERAL AREAS OF SHOWERS AND THUNDERSTORMS EXIST AT THE MOMENT FROM
ILLINOIS BACK TO KANSAS AND OKLAHOMA. AT THE MOMENT THE MODEL THAT
IS REFLECTING THE CURRENT RADAR BEST IS THE HRRR. LEANED TOWARD ITS
SOLUTION TODAY IN REGARDS TO POPS.
A WARM FRONT WILL MOVE ACROSS THE AREA LATER TODAY...PROVIDING LIFT
ALONG AND WELL AHEAD OF THE FRONT. UPPER IMPULSES WILL PROVIDE
SUPPORT TO THE LIFT ALREADY BEING GENERATED BY THE WARM FRONT.
THE LIFT PLUS MOISTURE BEING PULLED NORTH INTO THE AREA SHOULD LEAD
TO PERIODS OF SHOWERS AND THUNDERSTORMS ACROSS THE ENTIRE AREA
TODAY. MOS POPS AND THE HRRR FORECAST AGREE WITH THIS...SO FEEL NO
NEED TO CUT MOS POPS. WILL GO CATEGORICAL POPS NEARLY THE ENTIRE
AREA.
INSTABILITY PARAMETERS AND SPC FORECAST AGREE THAT SEVERE STORMS
SHOULD NOT OCCUR TODAY.
WITH THE RAIN ACROSS THE AREA TODAY AND A LATER ARRIVAL OF THE WARM
FRONT...WENT AHEAD AND TRIMMED BACK HIGHS TODAY FROM PREVIOUS
FORECAST. GENERALLY WENT BETWEEN THE COOLER MET AND WARMER MAV.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
ISSUED AT 305 AM EDT SAT APR 14 2012
FOCUS IS ON CHANCES FOR RAIN INTO MONDAY. MODELS ARE GENERALLY CLOSE
ENOUGH THAT A BLEND CAN BE USED.
THE WARM FRONT WILL BE ON ITS WAY NORTH OF THE AREA THIS EVENING.
KEPT LOW END LIKELY POPS ACROSS THE NORTHERN THIRD OF THE AREA WITH
CHANCE OR SLIGHT CHANCE POPS TO THE SOUTH. FOR THE OVERNIGHT PERIOD
WENT LOW POPS ACROSS THE FAR NORTHERN FORECAST AREA TO ACCOUNT FOR
ANY LINGERING RAIN. WENT ABOVE MOS FOR TEMPERATURES WITH SOUTHERLY
WINDS OVERNIGHT IN THE WARM SECTOR.
REMOVED ALL POPS FOR SUNDAY AS THE FORECAST AREA WILL BE IN THE WARM
SECTOR OF THE SYSTEM...AND THERE WILL NOT BE ANY FORCING IN THE
AREA. WITH SOME SUNSHINE AND WARM ADVECTION...WENT ABOVE MOS FOR
HIGHS. SUNDAY WILL ALSO BE WINDY AS STRONGER WINDS ALOFT MIX DOWN TO
PRODUCE GUSTS OVER 30 MPH.
THE COLD FRONT WILL MOVE INTO THE AREA SUNDAY NIGHT. DECENT FLOW AT
THE SURFACE AND ALOFT SHOULD BRING IN ENOUGH MOISTURE TO INTERACT
WITH THE FRONT FOR LIKELY OR HIGHER POPS MOST AREAS BY THE END OF
THE NIGHT.
THE FRONT WILL STILL BE CROSSING THE AREA EARLY MONDAY...AND BASED
ON EXPECTED TIMING WENT LIKELY POPS EXTREME EAST TO SLIGHT CHANCE
POPS EXTREME WEST DURING THE MORNING. DURING THE AFTERNOON ONLY WENT
SLIGHT CHANCE POPS ACROSS THE FAR SOUTHEAST AS THE FRONT SHOULD HAVE
TAKEN MOST OF THE RAIN WITH IT AS IT HEADS EAST OF THE AREA.
MONDAY NIGHT WILL BE DRY AND COOLER AS HIGH PRESSURE MOVES IN.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
ISSUED AT 305 AM EDT SAT APR 14 2012
EXTENDED PERIOD WILL START WITH DRY AND SEASONABLY COOL WEATHER AS
HIGH PRESSURE RIDGE DRIFTS ACROSS THE REGION. HIGHS WILL LARGELY
REMAIN IN THE 60S TUESDAY AND WEDNESDAY WITH RETURN SOUTHERLY FLOW
DEVELOPING BY LATE DAY AS THE HIGH MOVES EAST. LOW PRESSURE SET TO
TRACK INTO THE GREAT LAKES WEDNESDAY NIGHT WITH A WEAK FRONTAL
BOUNDARY SAGGING INTO CENTRAL INDIANA. MODEL CONSENSUS CONTINUES TO
LIMIT MOISTURE AND FORCING ALOFT ACROSS THE REGION...FOCUSING THE
BETTER LIFT FURTHER NORTH IN CLOSER PROXIMITY TO THE LOW. WILL
MAINTAIN LOW CHANCE POPS OVER FAR NORTHERN COUNTIES TO ACCOUNT FOR
ANY ISOLATED PRECIP THAT CAN MIGRATE INTO THE REGION WITH THE
BOUNDARY.
BOUNDARY WILL BECOME STALLED ACROSS THE REGION THURSDAY BEFORE
LIFTING BACK NORTH BY THURSDAY NIGHT IN RESPONSE TO A STRONGER WAVE
MOVING OUT OF THE CENTRAL PLAINS AND INTO THE MID MISSISSIPPI VALLEY
BY EARLY FRIDAY. EXTENDED MODELS IN GOOD AGREEMENT IN TRACKING THIS
WAVE AND THE ASSOCIATED COLD FRONT ACROSS THE FORECAST AREA ON
FRIDAY WITH WIDESPREAD RAIN AND THUNDERSTORMS. MAINTAINED HIGH
CHANCE POPS FOR FRIDAY AND FRIDAY NIGHT. TEMPERATURES LIKELY TO
RETURN TO THE 70S THURSDAY AND FRIDAY FOR MUCH OF THE FORECAST AREA
WITH SLIGHTLY COOLER TEMPERATURES BY SATURDAY IN WAKE OF THE FRONTAL
PASSAGE.
&&
.AVIATION /DISCUSSION FOR THE 140900Z TAF UPDATE/...
ISSUED AT 429 AM EDT SAT APR 14 2012
ISOLATED CONVECTION DEVELOPING OVER THE WESTERN HALF OF THE FORECAST
AREA AS WARM ADVECTION COMMENCES. MORE WIDESPREAD RAINFALL AND
THUNDERSTORMS PRESENT OVER SOUTHERN ILLINOIS WILL EXPAND EAST AND
IMPACT THE TERMINALS AFTER 10-11Z. HRRR HAS NICE HANDLE ON CURRENT
CONVECTIVE COVERAGE AND IS STRONGLY SUGGESTIVE OF SEVERAL WAVES OF
CONVECTION MOVING THROUGH CENTRAL INDIANA THROUGHOUT THE DAY. STILL
APPEARS MVFR CONDITIONS WILL DEVELOP BY LATE MORNING AND PERSIST
THROUGH THE AFTERNOON AS WARM FRONT MOVES INTO THE REGION.
06Z DISCUSSION FOLLOWS.
LATEST RADAR MOSAIC IS QUIET...EARLIER SHOWERS WERE QUICKLY ABSORBED
BY DRY ATMOSPHERE. HOWEVER...THE NEXT ROUND OF RAIN WILL ENTER TAF
SITES AFTER SAT 09Z AND WILL BE HEAVIER THAN THE PREVIOUS ROUND. A
FEW EMBEDDED THUNDERSTORMS COULD ALSO ACCOMPANY THE RAIN SHOWERS DUE
TO BETTER LIFT AHEAD OF A WARM FRONT. VFR CONDITIONS SHOULD PREVAIL
THROUGH DAYBREAK...BUT CONDITIONS WILL QUICKLY DETERIORATE TO
MVFR/IFR AFTER THAT AND REMAIN THAT WAY FOR MOST OF THE DAY.
THUNDERSTORM THREAT SHOULD DIMINISH THIS EVENING...BUT CONDITIONS
WILL REMAIN AT MVFR INTO THE NIGHT DUE TO LINGERING RAIN SHOWERS AND
LOW CEILINGS. VFR CONDITIONS WILL RETURN AT THE END OF TAF PERIOD.
WINDS WILL BE STRONG OUT OF THE SOUTH/SOUTHWEST WITH SUSTAINED
SPEEDS OF 8 TO 12 KTS AND GUSTS TO 30 KTS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...50
NEAR TERM...50
SHORT TERM...50
LONG TERM....RYAN
AVIATION...TDUD
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
305 AM EDT SAT APR 14 2012
.UPDATE...
THE SYNOPSIS...NEAR TERM...SHORT TERM...AND LONG TERM SECTIONS HAVE
BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 305 AM EDT SAT APR 14 2012
A WARM FRONT WILL MOVE THROUGH THE AREA LATER TODAY INTO
TONIGHT...BRINGING SHOWERS AND THUNDERSTORMS TO CENTRAL INDIANA. A
COLD FRONT WILL THEN MOVE THROUGH SUNDAY NIGHT INTO
MONDAY...BRINGING ANOTHER ROUND OF RAIN. DRY WEATHER WILL THEN
CONTINUE UNTIL LATE NEXT WEEK...WHEN ANOTHER FRONT BRINGS A CHANCE
FOR RAIN.
&&
.NEAR TERM /TODAY/...
ISSUED AT 305 AM EDT SAT APR 14 2012
SEVERAL AREAS OF SHOWERS AND THUNDERSTORMS EXIST AT THE MOMENT FROM
ILLINOIS BACK TO KANSAS AND OKLAHOMA. AT THE MOMENT THE MODEL THAT
IS REFLECTING THE CURRENT RADAR BEST IS THE HRRR. LEANED TOWARD ITS
SOLUTION TODAY IN REGARDS TO POPS.
A WARM FRONT WILL MOVE ACROSS THE AREA LATER TODAY...PROVIDING LIFT
ALONG AND WELL AHEAD OF THE FRONT. UPPER IMPULSES WILL PROVIDE
SUPPORT TO THE LIFT ALREADY BEING GENERATED BY THE WARM FRONT.
THE LIFT PLUS MOISTURE BEING PULLED NORTH INTO THE AREA SHOULD LEAD
TO PERIODS OF SHOWERS AND THUNDERSTORMS ACROSS THE ENTIRE AREA
TODAY. MOS POPS AND THE HRRR FORECAST AGREE WITH THIS...SO FEEL NO
NEED TO CUT MOS POPS. WILL GO CATEGORICAL POPS NEARLY THE ENTIRE
AREA.
INSTABILITY PARAMETERS AND SPC FORECAST AGREE THAT SEVERE STORMS
SHOULD NOT OCCUR TODAY.
WITH THE RAIN ACROSS THE AREA TODAY AND A LATER ARRIVAL OF THE WARM
FRONT...WENT AHEAD AND TRIMMED BACK HIGHS TODAY FROM PREVIOUS
FORECAST. GENERALLY WENT BETWEEN THE COOLER MET AND WARMER MAV.
&&
.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
ISSUED AT 305 AM EDT SAT APR 14 2012
FOCUS IS ON CHANCES FOR RAIN INTO MONDAY. MODELS ARE GENERALLY CLOSE
ENOUGH THAT A BLEND CAN BE USED.
THE WARM FRONT WILL BE ON ITS WAY NORTH OF THE AREA THIS EVENING.
KEPT LOW END LIKELY POPS ACROSS THE NORTHERN THIRD OF THE AREA WITH
CHANCE OR SLIGHT CHANCE POPS TO THE SOUTH. FOR THE OVERNIGHT PERIOD
WENT LOW POPS ACROSS THE FAR NORTHERN FORECAST AREA TO ACCOUNT FOR
ANY LINGERING RAIN. WENT ABOVE MOS FOR TEMPERATURES WITH SOUTHERLY
WINDS OVERNIGHT IN THE WARM SECTOR.
REMOVED ALL POPS FOR SUNDAY AS THE FORECAST AREA WILL BE IN THE WARM
SECTOR OF THE SYSTEM...AND THERE WILL NOT BE ANY FORCING IN THE
AREA. WITH SOME SUNSHINE AND WARM ADVECTION...WENT ABOVE MOS FOR
HIGHS. SUNDAY WILL ALSO BE WINDY AS STRONGER WINDS ALOFT MIX DOWN TO
PRODUCE GUSTS OVER 30 MPH.
THE COLD FRONT WILL MOVE INTO THE AREA SUNDAY NIGHT. DECENT FLOW AT
THE SURFACE AND ALOFT SHOULD BRING IN ENOUGH MOISTURE TO INTERACT
WITH THE FRONT FOR LIKELY OR HIGHER POPS MOST AREAS BY THE END OF
THE NIGHT.
THE FRONT WILL STILL BE CROSSING THE AREA EARLY MONDAY...AND BASED
ON EXPECTED TIMING WENT LIKELY POPS EXTREME EAST TO SLIGHT CHANCE
POPS EXTREME WEST DURING THE MORNING. DURING THE AFTERNOON ONLY WENT
SLIGHT CHANCE POPS ACROSS THE FAR SOUTHEAST AS THE FRONT SHOULD HAVE
TAKEN MOST OF THE RAIN WITH IT AS IT HEADS EAST OF THE AREA.
MONDAY NIGHT WILL BE DRY AND COOLER AS HIGH PRESSURE MOVES IN.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
ISSUED AT 305 AM EDT SAT APR 14 2012
EXTENDED PERIOD WILL START WITH DRY AND SEASONABLY COOL WEATHER AS
HIGH PRESSURE RIDGE DRIFTS ACROSS THE REGION. HIGHS WILL LARGELY
REMAIN IN THE 60S TUESDAY AND WEDNESDAY WITH RETURN SOUTHERLY FLOW
DEVELOPING BY LATE DAY AS THE HIGH MOVES EAST. LOW PRESSURE SET TO
TRACK INTO THE GREAT LAKES WEDNESDAY NIGHT WITH A WEAK FRONTAL
BOUNDARY SAGGING INTO CENTRAL INDIANA. MODEL CONSENSUS CONTINUES TO
LIMIT MOISTURE AND FORCING ALOFT ACROSS THE REGION...FOCUSING THE
BETTER LIFT FURTHER NORTH IN CLOSER PROXIMITY TO THE LOW. WILL
MAINTAIN LOW CHANCE POPS OVER FAR NORTHERN COUNTIES TO ACCOUNT FOR
ANY ISOLATED PRECIP THAT CAN MIGRATE INTO THE REGION WITH THE
BOUNDARY.
BOUNDARY WILL BECOME STALLED ACROSS THE REGION THURSDAY BEFORE
LIFTING BACK NORTH BY THURSDAY NIGHT IN RESPONSE TO A STRONGER WAVE
MOVING OUT OF THE CENTRAL PLAINS AND INTO THE MID MISSISSIPPI VALLEY
BY EARLY FRIDAY. EXTENDED MODELS IN GOOD AGREEMENT IN TRACKING THIS
WAVE AND THE ASSOCIATED COLD FRONT ACROSS THE FORECAST AREA ON
FRIDAY WITH WIDESPREAD RAIN AND THUNDERSTORMS. MAINTAINED HIGH
CHANCE POPS FOR FRIDAY AND FRIDAY NIGHT. TEMPERATURES LIKELY TO
RETURN TO THE 70S THURSDAY AND FRIDAY FOR MUCH OF THE FORECAST AREA
WITH SLIGHTLY COOLER TEMPERATURES BY SATURDAY IN WAKE OF THE FRONTAL
PASSAGE.
&&
.AVIATION /DISCUSSION FOR THE 140600Z TAF ISSUANCE/...
ISSUED AT 106 AM EDT SAT APR 14 2012
LATEST RADAR MOSAIC IS QUIET...EARLIER SHOWERS WERE QUICKLY ABSORBED
BY DRY ATMOSPHERE. HOWEVER...THE NEXT ROUND OF RAIN WILL ENTER TAF
SITES AFTER SAT 09Z AND WILL BE HEAVIER THAN THE PREVIOUS ROUND. A
FEW EMBEDDED THUNDERSTORMS COULD ALSO ACCOMPANY THE RAIN SHOWERS DUE
TO BETTER LIFT AHEAD OF A WARM FRONT. VFR CONDITIONS SHOULD PREVAIL
THROUGH DAYBREAK...BUT CONDITIONS WILL QUICKLY DETERIORATE TO
MVFR/IFR AFTER THAT AND REMAIN THAT WAY FOR MOST OF THE DAY.
THUNDERSTORM THREAT SHOULD DIMINISH THIS EVENING...BUT CONDITIONS
WILL REMAIN AT MVFR INTO THE NIGHT DUE TO LINGERING RAIN SHOWERS AND
LOW CEILINGS. VFR CONDITIONS WILL RETURN AT THE END OF TAF PERIOD.
WINDS WILL BE STRONG OUT OF THE SOUTH/SOUTHWEST WITH SUSTAINED
SPEEDS OF 8 TO 12 KTS AND GUSTS TO 30 KTS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...50
NEAR TERM...50
SHORT TERM...50
LONG TERM....RYAN
AVIATION...TDUD
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
106 AM EDT SAT APR 14 2012
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
ISSUED AT 315 PM EDT FRI APR 13 2012
LOW PRESSURE OVER THE NORTHERN PLAINS AND ANOTHER LOW PRESSURE
SYSTEM DEVELOPING NEAR COLORADO WILL PULL A WARM FRONT ACROSS OUR
REGION SATURDAY. THE COMBINATION OF STRONG ISENTROPIC LIFT AND AN
UPPER LEVEL WEATHER DISTURBANCE MOVING ACROSS OUR REGION WILL CAUSE
NUMEROUS SHOWERS AND SCATTERED THUNDERSTORMS TO DEVELOP VERY LATE
TONIGHT AND SATURDAY.
THE THUNDERSTORMS WILL DIMINISH FROM THE SOUTH BY LATE SATURDAY AS
THE FRONT MOVES ON TO THE NORTHEAST. AN UPPER RIDGE BUILDING OVER
THE SOUTHEAST U.S. INTO THE OHIO VALLEY WILL BRING A TEMPORARY END
TO THE THUNDERSTORMS OVER SOUTHERN SECTIONS AND A LESSER CHANCE TO
OUR NORTH SATURDAY NIGHT AND SUNDAY.
THE LOW PRESSURE SYSTEM WILL TRACK INTO THE GREAT LAKES AND MODELS
BRING A COLD FRONT ACROSS OUR REGION LATE SUNDAY NIGHT AND EARLY
MONDAY WHICH WILL CAUSE AGAIN AN INCREASED CHANCE OF THUNDERSTORMS
SUNDAY NIGHT AND EARLY MONDAY.
MOSTLY DRY WEATHER WILL BE THE RULE TUESDAY THROUGH THURSDAY AS HIGH
PRESSURE BEHIND THIS COLD FRONT MOVES ACROSS OUR REGION. ANOTHER
LOW PRESSURE SYSTEM WILL MOVE FROM THE MID MISSISSIPPI VALLEY INTO
THE GREAT LAKES BY DAY 7 BRINGING US A RETURN TO WARMER WEATHER AND
A CHANCE OF THUNDERSTORMS TOWARDS THE END OF THE 7 DAY FORECAST
PERIOD.
&&
.NEAR TERM /REST OF TONIGHT/...
ISSUED AT 952 PM EDT FRI APR 13 2012
DRY AIR HAS ERODED EARLIER RAIN SHOWERS TO NOTHING...AND DEWPOINTS
ACROSS THE EAST ARE STILL IN THE 30S WITH UPPER 20 DEWPOINTS IN
THE NORTHEAST. THUS REMOVED POPS FROM THE EAST FOR THE NEXT COUPLE
OF HOURS. FROM RUC AND HRRR STILL LOOKS LIKE DEVELOPMENT
WILL OCCUR AHEAD OF THE WARM FRONT ON ISENTROPIC LIFT AND
OVERSPREAD THE AREA IT JUST MAY BE A BIT SLOWER THAN EARLIER
FORECAST. THUS DELAYED THE HIGHEST POPS OF THE OVERNIGHT PERIOD
UNTIL AFTER 9Z. ALSO DROPPED OVERNIGHT LOWS A BIT GIVEN THE LOW
DEWPOINTS AND RATE OF TEMPERATURE FALL ALREADY...BUT THINK THIS
WILL OCCUR RELATIVELY EARLY DURING THE OVERNIGHT PERIOD AND THEN
TEMPERATURES WILL REMAIN STEADY OR EVEN RISE A BIT WITH THE WARM
ADVECTION AND RAIN. COULD STILL SEE A LITTLE ELEVATED INSTABILITY
AND THUS LEFT ISOLATED THUNDER MENTION GOING.
&&
.SHORT TERM /SATURDAY THROUGH MONDAY/...
ISSUED AT 315 PM EDT FRI APR 13 2012
FOCUS IS ON CHANCES FOR RAIN THROUGH THE PERIOD. MODELS ARE IN
FAIRLY GOOD AGREEMENT AND WILL USE BLEND.
MODELS HAVE TRENDED TOWARDS A VERY WET DAY SATURDAY AS STRONG
ISENTROPIC LIFT WILL BE OCCURRING AND AN UPPER LEVEL WEATHER
DISTURBANCE WILL BE MOVING ACROSS OUR AREA. PRECIP WILL BEGIN
DIMINISHING LATE SATURDAY AND GRADUALLY END OVER ALL BUT FAR
NORTHERN AREAS LATER SATURDAY NIGHT.
SUNDAY WILL BE BREEZY AND UNSEASONABLY WARM. MODELS CONTINUE TO
INDICATE CONVECTION WILL BE ACROSS OUR NORTHWEST ESPECIALLY LATE
SUNDAY. LOW PRESSURE WILL TRACK INTO THE GREAT LAKES SUNDAY NIGHT
AND A COLD FRONT WILL MOVE INTO OUR REGION LATE SUNDAY NIGHT AND
EARLY MONDAY AND CONTINUE RAPIDLY EAST OF OUR AREA BY MONDAY
AFTERNOON. WILL GO CLOSE TO A MODEL BLEND WHICH INDICATES HIGH POPS
ALL BUT FAR EASTERN SECTIONS BY LATE SUNDAY NIGHT AND ACROSS THE
EAST MONDAY MORNING. PRECIP MAY END BY MONDAY AFTERNOON...BUT
SEVERAL OF THE SURROUNDING OFFICES KEEP IN 20 PERCENT POPS AND WILL
FOLLOW SUIT.
WINDS WILL BE QUITE STRONG BOTH SUNDAY AND MONDAY WITH GUSTS
APPROACHING 30 MPH SUNDAY AND 25 TO 30 MPH MONDAY.
AS FAR AS TEMPERATURES ARE CONCERNED WENT CLOSE TO A MAV/MET BLEND
SATURDAY AND RAISED A FEW DEGREES MOST OTHER PERIODS.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
ISSUED AT 315 PM EDT FRI APR 13 2012
MAIN FORECAST CONCERN THROUGHOUT THE LONG TERM IS
PRECIPITATION...WITH SLIGHT CHANCES WEDNESDAY NIGHT AND MORE LIKELY
CHANCES ON FRIDAY.
THE LONG TERM PERIOD BEGINS WITH A COLD FRONT EXITING THE REGION
MONDAY NIGHT. MODELS CONTINUE TO BE PROGRESSIVE WITH THE EASTWARD
PROGRESSION OF THIS FRONT AND ANY ASSOCIATED RAIN CHANCES.
THEREFORE...WENT DRY FOR THE MAJORITY OF THE AREA AFTER 00Z TUESDAY
EXCEPT FOR A SLIGHT CHANCE ACROSS THE FAR EAST TO ACCOUNT FOR ANY
LINGERING PRECIPITATION. NORTHERLY FLOW BEHIND THE FRONT WILL ALLOW
TEMPERATURES ON MONDAY NIGHT TO BE MUCH LOWER THAN PREVIOUS NIGHTS
WITH READINGS FALLING INTO THE 40S.
HIGH PRESSURE WILL QUICKLY BUILD INTO THE REGION FROM THE NORTH WITH
DRY CONDITIONS EXPECTED ON TUESDAY AND THROUGHOUT THE DAY ON
WEDNESDAY. WITH COOLER AIR FLOWING DOWN FROM CANADA...TEMPERATURES
WILL REMAIN MUCH LOWER THAN EARLIER IN THE WEEK WITH HIGHS RANGING
FROM THE UPPER 50S TO MID 60S...ALTHOUGH STILL AROUND AVERAGE.
ALL MODELS DEPICT LOW PRESSURE DEVELOPING ACROSS THE NORTHERN PLAINS
ON WEDNESDAY AND TRACKING TOWARDS THE GREAT LAKES BY WEDNESDAY
EVENING. THE BULK OF ANY PRECIPITATION LOOKS TO BE ACROSS THE
NORTHERN HALF OF THE FORECAST AREA AND NORTHWARD. THEREFORE...STUCK
WITH ALLBLEND SLIGHT CHANCE POPS JUST ACROSS THE NORTH.
THE MAIN SYSTEM DURING THE PERIOD WILL BE A STRONG LOW PRESSURE
SYSTEM DEVELOPING ACROSS THE PLAINS AND TRACKING TOWARDS THE MIDWEST
ON FRIDAY. THE GFS...ECMWF AND GEM ARE IN PRETTY DECENT AGREEMENT IN
REGARDS TO TIMING AND PRECIPITATION CHANCES ENTERING THE AREA BY
FRIDAY AFTERNOON AND LINGERING THROUGHOUT THE END OF THE PERIOD.
HOWEVER...PER COLLABORATION...ADJUSTED ALLBLEND POPS DOWN SLIGHTLY
FROM CATEGORICAL TO THE 40-50 PERCENT RANGE TO ACCOUNT FOR THE LONG
TERM NATURE OF THE FORECAST AND ANY CHANGES IN TIMING.
&&
.AVIATION /DISCUSSION FOR THE 140600Z TAF ISSUANCE/...
ISSUED AT 106 AM EDT SAT APR 14 2012
LATEST RADAR MOSAIC IS QUIET...EARLIER SHOWERS WERE QUICKLY ABSORBED
BY DRY ATMOSPHERE. HOWEVER...THE NEXT ROUND OF RAIN WILL ENTER TAF
SITES AFTER SAT 09Z AND WILL BE HEAVIER THAN THE PREVIOUS ROUND. A
FEW EMBEDDED THUNDERSTORMS COULD ALSO ACCOMPANY THE RAIN SHOWERS DUE
TO BETTER LIFT AHEAD OF A WARM FRONT. VFR CONDITIONS SHOULD PREVAIL
THROUGH DAYBREAK...BUT CONDITIONS WILL QUICKLY DETERIORATE TO
MVFR/IFR AFTER THAT AND REMAIN THAT WAY FOR MOST OF THE DAY.
THUNDERSTORM THREAT SHOULD DIMINISH THIS EVENING...BUT CONDITIONS
WILL REMAIN AT MVFR INTO THE NIGHT DUE TO LINGERING RAIN SHOWERS AND
LOW CEILINGS. VFR CONDITIONS WILL RETURN AT THE END OF TAF PERIOD.
WINDS WILL BE STRONG OUT OF THE SOUTH/SOUTHWEST WITH SUSTAINED
SPEEDS OF 8 TO 12 KTS AND GUSTS TO 30 KTS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...JH
NEAR TERM...CP
SHORT TERM...JH
LONG TERM....AJH/JH
AVIATION...TDUD
AREA FORECAST DISCUSSION
NWS WICHITA KS
333 PM CDT SAT APR 14 2012
.DISCUSSION...
MAIN FORECAST CONCERN: THIS EVENING AND TONIGHT WILL BE THE MOST
CONCERNING PORTION OF THE FORECAST WITH AMPLIFIED SEVERE THREAT FOR
THE COUNTY WARNING AREA. OTHERWISE...THE ISSUES INCLUDE THE POPS FOR
SUNDAY INTO MONDAY WITH THE LOW PUSHING OUT OF THE AREA AND ANY
POTENTIAL WRAP AROUND.
TONIGHT:
DRYLINE WILL BE EVEN SLOWER TO MOVE ACROSS THE AREA...MOST LIKELY
LATER TONIGHT. HOWEVER CONSIDERABLE INSTABILITY/SHEAR ALREADY IN
PLACE...WITH ISOLATED SEVERE STORMS JUST WEST OF AREA AT THIS
TIME. BELIEVE CONDITIONS ARE SUFFICIENT FOR THESE TO CONTINUE AS
THEY MOVE EAST...WITH WITH SOUTHERN SECTIONS LIKELY HAVING BETTER
INSTABILITY THROUGH SUNSET. GIVEN HODOGRAPHS...SUPERCELLS WITH
TORNADIC POTENTIAL WILL EXIST...WELL INTO THE EVENING. DRYLINE
SHOULD SWEEP ACROSS THE AREA DURING MIDDLE OF THE NIGHT.
TEMPERATURES WILL LIKELY REMAIN QUASI STEADY AHEAD OF THE DRYLINE
GIVEN THE LOW LEVEL MOISTURE AND GRADIENT WINDS. -HOWERTON
SUNDAY:
BETTER ALIGNMENT OF THE SURFACE AND UPPER LEVEL TROUGH WHICH WILL
CONTINUE TO PUSH OFF TO THE NORTHEAST ON SUNDAY. A COLD FRONT WITH
THIS SYSTEM IS ANTICIPATED TO SLIDE THROUGH CENTRAL KANSAS FIRST
THEN THROUGH THE REST OF SOUTH CENTRAL AND SOUTHEAST KANSAS THROUGH
THE DAY. THERE IS CONCERN OF STRONG WINDS AHEAD OF AND BEHIND
FRONTAL PASSAGE WITH SUSTAINED SPEEDS JUST SHY OF WIND ADVISORY
CRITERIA BASED ON CURRENT TRENDS. DECIDED AGAINST ISSUING ANY WIND
HEADLINES RIGHT NOW...BUT THE NEXT FORECAST MAY DECIDE TO GO FORWARD
WITH IT. THERE MAY BE LINGERING SHOWERS AND THUNDERSTORMS WITH THE
EXITING LOW WHICH WILL CONTINUE INTO THE MORNING AND AFTERNOON HOURS
IN SOUTHEAST KANSAS...BUT SEVERE POTENTIAL DOES NOT APPEAR TO BE
HIGH WITH THE MAJOR SOURCES OF INSTABILITY DIMINISHING. DID DECREASE
THE POPS SUNDAY EVENING AND NIGHT AS THE PROGRESSION OF THE SYSTEM
APPEARS TO BE MUCH QUICKER THAN PREVIOUSLY ANTICIPATED.
MONDAY:
A SECONDARY WAVE APPEARS TO BE ASSOCIATED WITH THE UPPER LEVEL AT
500MB THAT WILL SLIDE THROUGH ON MONDAY...YET HIGH PRESSURE AT THE
SURFACE TO 850MB. THERE MAY BE A FEW SHOWERS ASSOCIATED WITH THIS
WAVE PARTICULARLY IN CENTRAL AND POTENTIALLY SOUTH CENTRAL KANSAS.
PV DOES INDICATE A PIECE ENERGY MOVING WITH THIS SYSTEM...HOWEVER
MODELS VARY IN LOCATION AND DEVELOPMENT OF ANY PRECIPITATION. THUS
DECIDED TO WAIT ON CHANCES FOR NOW.
TUESDAY TO SATURDAY:
THE NEXT TROUGH WILL START TO DO MOST OF ITS DEVELOPMENT WHEN IT
MOVES OVER THE ROCKIES FOR WEDNESDAY TO THURSDAY...HOWEVER 850MB
INDICATES THE MAIN SYSTEM TO STAY IN THE NORTHERN PLAINS. AT THE
SURFACE...THERE IS INDICATION OF THE LOW PASSING THROUGH ON THURSDAY
WITH SOME ASSOCIATED INSTABILITY FOR THE AFTERNOON AND EVENING
HOURS. THUS KEPT THUNDERSTORM CHANCES IN FOR THIS TIME FRAME.
MOVEMENT OF THIS NEXT TROUGH IN THIS EXTENDED IS A BIT QUESTIONABLE
WITH MODEL VARIATION IN THE TIMING...DEPTH AND EXACT LOCATION. THIS
COULD CHANGE ANY POTENTIAL IN POPS. TEMPERATURES ARE ON TRACK TO
CLIMB TO NEAR TO ABOVE NORMAL WITH THURSDAY LOOKING TO BE THE
WARMEST DAY OF THE WEEK WITH THE GOOD SURGE OF WARM AIR ADVECTION
OUT AHEAD OF THE NEXT SYSTEM.
VP
&&
.PREV DISCUSSION... /ISSUED 242 PM CDT SAT APR 14 2012/
UPDATE...
12 UTC AND LATER RUC MODEL RUNS SUGGEST DRYLINE WILL BE EVEN SLOWER
TO MOVE ACROSS THE AREA...MOST LIKELY LATER TONIGHT. THIS WILL
IMPACT SEVERE THREAT ACROSS THE AREA. AT THIS TIME...BEST
INSTABILITY/WEAKEST CAP IS OCCURRING ACROSS WESTERN SECTIONS OF
CENTRAL KS WITH CAP HOLDING ON ACROSS MOST OF SOUTH CENTRAL/
SOUTHEAST KS. GIVEN LACK OF SURFACE BOUNDARY AND EXTENSIVE CLOUDS
SO FAR...MAY BE TOUGH TO BREAK CAP ACROSS SOUTH CENTRAL KS THIS
AFTERNOON. HOWEVER A FEW SMALL BREAKS IN CLOUDS ARE EVIDENT IN
VISIBILITY SATELLITE SOUTH/WEST OF ICT. IF STORMS CAN DEVELOP IN
THIS AREA...CLEARLY ENVIRONMENT WOULD BE CONDUCIVE FOR STRONG/
SEVERE STORMS. BIGGEST THREAT TONIGHT IS ROUGHLY ALONG AND SOUTH
OF HIGHWAY 400 ACROSS SOUTH CENTRAL KS...EAST TO HIGHWAY 99 IN
THE 00-04 UTC TIME FRAME...WITH INCREASING ELEVATED STORM RISK
03-06 UTC ACROSS CENTRAL KS EAST OF I-135. -HOWERTON
&&
.AVIATION...18Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
CONVECTIVE TRENDS WILL BE THE MAIN ISSUE...WITH STRONG-SEVERE
THUNDERSTORMS IN THE VICINITY OF KRSL AT START. ISOLATED-SCATTERED
RAIN SHOWERS/THUNDERSTORMS WILL BE POSSIBLE DURING THE AFTERNOON AT
KSLN/KHUT/KICT...BUT EXPECT COVERAGE/INTENSITY TO RAMP UP TOWARDS
0000 UTC...WITH 0000 UTC-06 UTC THE MOST ACTIVE AT KHUT/KICT/KSLN.
IFR CONDITIONS...LARGE HAIL AND 50KT+ WINDS WILL BE BRIEFLY
POSSIBLE WITH ANY OF THE SEVERE STORMS. DRYLINE SHOULD ENTER THE
AREA LATER TONIGHT...BRINGING END TO PRECIPITATION AND LOSS OF
CEILING. GUSTY SOUTHWEST WINDS ANTICIPATED BEHIND DRYLINE.
-HOWERTON
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 55 71 44 66 / 60 10 0 10
HUTCHINSON 52 69 44 66 / 50 10 0 10
NEWTON 54 70 45 65 / 60 10 10 10
ELDORADO 57 71 45 67 / 70 10 10 10
WINFIELD-KWLD 57 72 45 69 / 60 10 10 10
RUSSELL 48 63 39 64 / 50 20 10 20
GREAT BEND 49 64 39 64 / 60 20 10 20
SALINA 52 69 43 65 / 60 10 10 20
MCPHERSON 52 69 44 65 / 60 10 10 10
COFFEYVILLE 65 74 47 68 / 50 50 10 10
CHANUTE 63 73 47 67 / 50 50 10 10
IOLA 63 72 47 66 / 50 50 10 10
PARSONS-KPPF 64 73 47 68 / 50 50 10 10
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 10 PM CDT THIS EVENING FOR KSZ032-033-
047>053-067>070-082-083-091>094-098.
&&
$$
AREA FORECAST DISCUSSION
NWS WICHITA KS
242 PM CDT SAT APR 14 2012
.UPDATE...
12 UTC AND LATER RUC MODEL RUNS SUGGEST DRYLINE WILL BE EVEN SLOWER
TO MOVE ACROSS THE AREA...MOST LIKELY LATER TONIGHT. THIS WILL
IMPACT SEVERE THREAT ACROSS THE AREA. AT THIS TIME...BEST
INSTABILITY/WEAKEST CAP IS OCCURRING ACROSS WESTERN SECTIONS OF
CENTRAL KS WITH CAP HOLDING ON ACROSS MOST OF SOUTH CENTRAL/
SOUTHEAST KS. GIVEN LACK OF SURFACE BOUNDARY AND EXTENSIVE CLOUDS
SO FAR...MAY BE TOUGH TO BREAK CAP ACROSS SOUTH CENTRAL KS THIS
AFTERNOON. HOWEVER A FEW SMALL BREAKS IN CLOUDS ARE EVIDENT IN
VISIBILITY SATELLITE SOUTH/WEST OF ICT. IF STORMS CAN DEVELOP IN
THIS AREA...CLEARLY ENVIRONMENT WOULD BE CONDUCIVE FOR STRONG/
SEVERE STORMS. BIGGEST THREAT TONIGHT IS ROUGHLY ALONG AND SOUTH
OF HIGHWAY 400 ACROSS SOUTH CENTRAL KS...EAST TO HIGHWAY 99 IN
THE 00-04 UTC TIME FRAME...WITH INCREASING ELEVATED STORM RISK
03-06 UTC ACROSS CENTRAL KS EAST OF I-135. -HOWERTON
&&
.PREV DISCUSSION... /ISSUED 1240 PM CDT SAT APR 14 2012/
AVIATION...18Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
CONVECTIVE TRENDS WILL BE THE MAIN ISSUE...WITH STRONG-SEVERE
THUNDERSTORMS IN THE VICINITY OF KRSL AT START. ISOLATED-SCATTERED
RAIN SHOWERS/THUNDERSTORMS WILL BE POSSIBLE DURING THE AFTERNOON AT
KSLN/KHUT/KICT...BUT EXPECT COVERAGE/INTENSITY TO RAMP UP TOWARDS
0000 UTC...WITH 0000 UTC-06 UTC THE MOST ACTIVE AT KHUT/KICT/KSLN.
IFR CONDITIONS...LARGE HAIL AND 50KT+ WINDS WILL BE BRIEFLY
POSSIBLE WITH ANY OF THE SEVERE STORMS. DRYLINE SHOULD ENTER THE
AREA LATER TONIGHT...BRINGING END TO PRECIPITATION AND LOSS OF
CEILING. GUSTY SOUTHWEST WINDS ANTICIPATED BEHIND DRYLINE.
-HOWERTON
PREV DISCUSSION... /ISSUED 729 AM CDT SAT APR 14 2012/
UPDATE...
THE FORECAST WILL BE UPDATED TO REMOVE THE TORNADO WATCH ACROSS
EXTREME SOUTHEAST KANSAS EARLY THIS MORNING. THE FORECAST FOR THIS
AFTERNOON/EVENING APPEARS ON TRACK WITH SUPERCELL THUNDERSTORMS
AND TORNADOES STILL EXPECTED.
MWM
PREV DISCUSSION... /ISSUED 645 AM CDT SAT APR 14 2012/
AVIATION...12Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
A WIDE RANGE OF FLIGHT CATEGORIES IS PRESENT ACROSS THE AREA THIS
MORNING ALTHOUGH MVFR SHOULD PREVAIL AT MOST LOCATIONS THROUGH THE
MORNING HOURS. SOME LOWER VISIBILITIES AND CEILINGS DEVELOPED
ACROSS PORTIONS OF CENTRAL KANSAS WHERE LOW LEVEL MOISTURE
ADVECTED NORTHWEST AFTER THE ONSET OF RADIATIONAL COOLING. FURTHER
SOUTH AND EAST...LINGERING THUNDERSTORMS WILL CONTINUE TO IMPACT
KCNU THROUGH 13-14Z WITH MVFR CIGS LIKELY THROUGH MUCH OF THE
MORNING. STRONG SOUTHERLY WINDS ARE EXPECTED TO DEVELOP EAST OF
THE DRYLINE WITH WIDELY SCATTERED SEVERE THUNDERSTORMS EXPECTED TO
DEVELOP ALONG AND EAST OF THE DRYLINE AFTER 21-22Z. THUNDERSTORMS MAY
LINGER THROUGH THE EVENING HOURS BEFORE DEVELOPING INTO A SQUALL
LINE TOWARDS MIDNIGHT AND SPREADING EAST ACROSS THE AREA. THIS
WILL LIKELY RESULT IN A TRANSIENT PERIOD OF REDUCED FLIGHT
CATEGORIES AND A PERIOD OF ERRATIC WIND GUSTS ACROSS MUCH OF THE
AREA.
MWM
PREV DISCUSSION... /ISSUED 328 AM CDT SAT APR 14 2012/
DISCUSSION...
MAIN FORECAST CONCERN WILL BE MORNING CONVECTION CHANCES...THEN
AN EXPECTED TORNADO OUTBREAK TOWARDS EVENING.
THIS MORNING:
CONVECTION OVER NRN OK WILL CONTINUE TO MOVE TO THE NORTHEAST
THIS MORNING...AS WARM ADVECTION INCREASES ACROSS SRN KS...AND
SLOWLY VEERS TO THE NORTHEAST WITH TIME. THIS WILL LEAD TO THE
MAIN CONVECTION LIFTING TO THE NORTH-NORTHEAST AS THE MORNING
PROGRESSES ACROSS ACROSS SRN KS. SO WILL CARRY THE HIGHEST POPS
FOR AREAS ALONG AND EAST OF THE TURNPIKE FOR THE MORNING
HOURS...WITH POPS DIMINISHING ACROSS SOUTH CEN AND CEN KS.
NEXT CONCERN WILL BE STRONG GUSTY WINDS IN THE WARM SECTOR FOR THE
DAYTIME HOURS AS CYCLOGENESIS GETS UNDER WAY ACROSS NW KS. TIGHT
GRADIENT AHEAD OF THIS SYSTEM SUGGEST SOME WIND GUSTS TO 45 MPH
POSSIBLE...SO CURRENT WIND ADVISORY LOOKS OKAY.
THIS AFTERNOON/EVENING:
MORNING CONVECTION IS EXPECTED TO LEAVE LOTS OF DEBRIS CLOUD COVER
ACROSS THE AREA FOR MOST OF THE MID-DAY TIME FRAME. CURRENT GFS AND
NAM/WRF SHOWS THAT THE DRY LINE IS EXPECTED TO PUSH WEST ALL WAY
BACK TO ALMOST KDDC...WITH UNSTABLE AIRMASS EXPECTED TO BE IN PLACE
TO THE EAST OF IT...FOR AREAS WEST OF INTERSTATE 135. AS THE
AFTERNOON PROGRESSES...CLOUD COVER WILL GENERALLY SCATTER OUT FOR
AREAS WEST OF A KSLN-KICT LINE AS THE DRY LINE BEGINS TO PUSH EAST
LATE THIS AFTERNOON...REACHING A KHYS TO KP28 LINE BETWEEN 21Z-00Z.
CURRENT THINKING...SUGGESTS THAT WITH THE DRY LINE EXPECTED TO BE
FURTHER WEST...THAT STORM INITIATION WILL BE DELAYED UNTIL CLOSER TO
00Z/SUN...AS CONVERGENCE INCREASES ALONG THE DRY LINE...JUST WEST OF
THE FORECAST AREA. THE BEST COMBINATION OF BULK SHEAR (AROUND 85
KTS) AND INSTABILITY LOOKS TO BE FOCUSED ACROSS NORTH CENTRAL
KS...WITH A MORE UNSTABLE AIRMASS FURTHER SOUTH ACROSS SOUTH CENTRAL
KS. SO EXPECTING MORE WIDESPREAD TORNADIC SUPERCELLS FROM CEN KS
NORTH INTO NEB...WHILE AREAS FURTHER SOUTH MAY SEE MORE ISOLATED
COVERAGE.
WITH THAT SAID...SHEAR (70-80KTS) AND INSTABILITY (MLCAPE 2000-3000
J/KG) ALONG THE DRY LINE...FURTHER SOUTH...LOOKS VERY FAVORABLE FOR
LONG LIVED SUPERCELL THUNDERSTORMS AND POSSIBLE STRONG TORNADOES.
SO ONCE THE STORMS DEVELOP...THEY WILL CERTAINLY PRODUCE LARGE HAIL
AND A FEW TORNADOES. STILL THE CHANCE FOR SOME STRONG/LONG TRACK
TORNADOES LOOKS VALID...WITH LARGE LOOPING HODOGRAPHS...WITH 0-1KM
STORM RELATIVE HELICITY VALUES OF 350-400 M2/S2 JUST W-SW OF KHUT BY
00Z/SUN. BUT ALSO THINK THE SUPERCELLS WILL BE MORE ISOLATED IN
NATURE. THE REAL CONCERN WILL BE INITIATION A FEW HOURS BEFORE
SUNSET...WITH CHANCES OF STRONG TORNADOES STILL ONGOING AFTER SUNSET
BEING A REAL CONCERN...WHEN SPOTTING THEM IS MORE DIFFICULT. A FEW
HIGH RESOLUTION MODELS SUGGEST TWO OR THREE LARGE SUPERCELLS WILL
MOVE ACROSS THE AREA...BUT PLACEMENT IS STILL UNCERTAIN. CURRENT
GUESS PLACES THE BEST CHANCE FROM KHUT SOUTH TO THE OK/KS LINE.
THE SUPERCELLS WILL GRADUALLY SHIFT EAST-NORTHEAST AFTER DARK...AS
THE SHORTWAVE MOVING ACROSS NEB HELPS PUSH THE DRYLINE INTO ERN KS.
THIS WILL PUSH MOST OF THE CONVECTION INTO ERN KS AND WRN MO.
SUN:
CONVECTION MAY STILL BE ONGOING ACROSS EXTREME SERN KS FOR THE
EARLY PART ON SUN...AS MAIN SHORTWAVE ENERGY MOVES ACROSS CEN KS.
AS THIS SHORTWAVE MOVES ACROSS CEN KS DURING THE AFTERNOON...
HEATING COULD SEE SOME DIURNALLY DRIVEN SHOWERS AND ISOLATED STORMS
ACROSS CEN KS. SO WILL KEEP THIS CHANCE IN PLACE.
MON-TUE:
WEAK RIDGING MOVES OVER THE AREA FOR THE BEGINNING OF THE
WEEK...ALLOWING THE AREA TO DRY OUT SOME. WILL ALSO TEMPS CLOSER TO
SEASONAL AVERAGES WITH SUNNY SKIES.
REST OF THE EXTENDED:
DIDN MAKE TOO MANY CHANGES TO THE EXTENDED...WITH THE MEDIUM RANGE
MODELS SHOWING ZONAL FLOW AND SEASONAL TEMPS FOR TUE THROUGH THU.
BOTH THE GFS AND ECMWF SHOW A WEAK SYSTEM PUSHING THROUGH THE AREA
FOR THU AND THU NIGHT. SO WILL GO WITH POPS FOR THIS CHANCE.
KETCHAM
AVIATION...06Z TAFS KRSL/KSLN/KHUT/KICT/KCNU
NUMEROUS THUNDERSTORMS ANTICIPATED TO CONTINUE FESTERING OVER
SOUTHEAST KS THE NEXT SEVERAL HOURS...WITH ACTIVITY POSSIBLY
DEVELOPING FURTHER WEST/NORTHWEST AS THE OVERNIGHT
PROGRESSES...POSSIBLY AFFECTING KICT-KHUT-KRSL-KSLN. COULD
POTENTIALLY SEE IFR OR LOWER CIGS/VSBYS DEVELOP OVERNIGHT FOR
MAINLY KRSL...AS HIGHER DEWPOINTS SLAM INTO A RADIATED OUT
AIRMASS. ONLY WENT 2SM FOR NOW...BUT COULD SEE PATCHY LIFR. STORM
CHANCES WILL GRADUALLY EXIT EASTWARD SATURDAY MORNING...ALONG WITH
IMPROVING CIGS. ANTICIPATING A FEW ISOLATED HIGH-END SEVERE STORMS
ACROSS THE REGION BY 21Z SATURDAY...ALONG AND AHEAD OF A DRYLINE
APPROACHING FROM THE WEST.
ADK
&&
.PRELIMINARY POINT TEMPS/POPS...
WICHITA-KICT 74 55 71 44 / 30 60 10 10
HUTCHINSON 73 52 70 44 / 40 50 10 10
NEWTON 75 54 70 45 / 30 60 10 10
ELDORADO 74 57 71 46 / 30 70 10 10
WINFIELD-KWLD 76 57 72 46 / 30 60 10 10
RUSSELL 73 48 66 42 / 40 50 20 10
GREAT BEND 74 49 67 43 / 40 60 20 10
SALINA 74 52 71 43 / 40 60 10 10
MCPHERSON 74 52 70 44 / 40 60 10 10
COFFEYVILLE 79 65 74 48 / 60 50 60 10
CHANUTE 78 63 73 47 / 60 50 60 10
IOLA 77 63 72 47 / 60 50 60 10
PARSONS-KPPF 78 64 73 47 / 60 50 60 10
&&
.ICT WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 10 PM CDT THIS EVENING FOR KSZ032-033-
047>053-067>070-082-083-091>094-098.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS PADUCAH KY
901 PM CDT SUN APR 15 2012
.UPDATE...
ISSUED AT 844 PM CDT SUN APR 15 2012
THIS NEAR TERM DISCUSSION IS ISSUED TO ACKNOWLEDGE THE EXPIRATION
OF THE EARLIER LAKE WIND ADVISORY AT 7 PM CDT...AND THE RECENT
CANCELLATION OF THE TORNADO WATCH NUMBER 180 FOR
CARTER...RIPLEY...WAYNE AND BUTLER COUNTIES IN SOUTHEAST MISSOURI.
GOES IMAGERY DERIVED LIFTED INDEX VALUES HAVE BEEN SHOWING A
GRADUAL TREND TOWARD A MORE STABLE ENVIRONMENT AND THE
PRECIPITABLE WATER VALUES SUGGEST THAT THE MAIN PLUME WILL BE
FIXED WITH THE VICINITY OF CURRENT CONVECTION.
THE PREFERRED 3KM HRRR MODEL GUIDANCE SUGGESTS THAT THE SURFACE-
BASED PEAK HELICITIES /ALSO SUGGESTED BY THE 4KM NAM-WRF...12KM
NAM AND 40KM GFS GUIDANCE ON SATURDAY/ AND CAPE WOULD DIMINISH
AFTER MOVING OUT OF SOUTHEAST MISSOURI BETWEEN THE 23Z SUNDAY -
03Z MONDAY /6-9 PM CDT SUNDAY NIGHT/.
WITH THAT IN MIND...ATTEMPTED TO BLEND THE HRRR GUIDANCE TIMING OF
THE PRECIPITATION ACROSS THE WFO PAH CWA FOR THE REST OF TONIGHT
AND INTO MONDAY MORNING. IN ADDITION...UTILIZED DIFFERENTIAL
POP/WEATHER FOR THUNDERSTORMS VS. RAINSHOWERS AS THE ELEVATED
INSTABILITY DECREASES OVERIGHT AND INTO MONDAY MORNING.
WILL LIKELY MAKE ANOTHER INTERIM UPDATE BEFORE MIDNIGHT TO ADDRESS
TEMPERATURES AND WINDS IN AND AROUND THE CONVECTIVE RAIN SHIELD.
&&
.SHORT TERM...(TONIGHT THROUGH TUESDAY)
ISSUED AT 205 PM CDT SUN APR 15 2012
THE MAIN FOCUS IN THE SHORT TERM WILL BE THE PASSAGE OF A COLD
FRONT LATE TONIGHT INTO MONDAY MORNING AND THE SHOWERS...
THUNDERSTORMS...AND OTHER WEATHER PHENOMENA ASSOCIATED WITH IT.
A LINE OF THUNDERSTORMS BISECTING THE STATE OF MISSOURI FROM
NORTHEAST TO SOUTHWEST AT THE TIME OF THIS WRITING IS EXPECTED TO
PROGRESS EASTWARD WITH THE AFOREMENTIONED FRONTAL SYSTEM THIS
EVENING AND OVERNIGHT.
AS THE SYSTEM MOVES EASTWARD THIS AFTERNOON AND EVENING...MODELS
ARE INDICATING AN INCREASE IN INSTABILITY AND SHEAR VALUES. WITH
ML CAPE VALUES APPROACHING 2000 J/KG AND DEEP LAYER SHEAR OF 50+
KTS...EXPECT STORMS TO INTENSIFY INTO A QLCS WITH THE POSSIBILITY
OF A COUPLE OF EMBEDDED SUPERCELLS.
BY LATE EVENING INTO THE EARLY MORNING HOURS...STORMS WILL LIKELY
WEAKEN AS INSTABILITY AND WIND SHEAR DECREASE A BIT. AS RESULT...
THE STORM PREDICTION CENTER HAS ALL BUT THE EASTERN THIRD OF OUR
CWA IN A SLIGHT RISK AREA FOR SEVERE THUNDERSTORMS. STORMS SHOULD BE
EXITING THE SOUTHEAST CORNER OF OUR CWA BY 3-4 PM MONDAY AFTERNOON.
AS IS OFTEN THE CASE...MODEL RUNS CONTINUE TO SLOW DOWN THE FORWARD
PROGRESS OF A PARTICULAR SYSTEM...SO LATER SHIFTS MAY HAVE TO
ADJUST ACCORDINGLY. IN THE WAKE OF THIS SYSTEM...HIGH PRESSURE
WILL DOMINATE THROUGH THE END OF THE SHORT TERM PERIOD.
GUSTY SOUTH WINDS OF 20 TO 30 MPH THIS AFTERNOON WILL DECREASE TO
10 TO 20 MPH AND VEER AROUND TO THE SOUTHWEST OVERNIGHT...THEN OUT
OF THE WEST STARTING MONDAY MORNING.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 205 PM CDT SUN APR 15 2012
BY MID WEEK...A ZONAL FLOW PATTERN WILL BECOME ESTABLISHED ACROSS
THE NATIONS MID SECTION. AS HIGH PRESSURE DEPARTS TO THE EAST...WARM
SOUTHERLY WINDS WILL RETURN IN THE LOW LEVELS. TEMPERATURES ARE
FORECAST TO REACH THE MID TO UPPER 70S BOTH WEDNESDAY AND THURSDAY
AFTERNOONS WITH PLENTY OF SUNSHINE BOTH DAYS.
THE CHANCE FOR SHOWERS AND THUNDERSTORMS WILL RETURN TO THE FORECAST
LATE THURSDAY INTO FRIDAY AS A DEVELOPING STORM SYSTEM APPROACHES
FROM THE PLAINS. DETERMINISTIC MODELS HAVE BEEN RATHER INCONSISTENT
ON TIMING THIS SYSTEM. MOST RECENT GFS OPERATIONAL RUNS HAVE FAVORED
A DEEPER AND SLOWER SOLUTION...WHILE RECENT ECMWF RUNS HAVE BEEN
FAIRLY CONSISTENT WITH A MORE PROGRESSIVE SOLUTION THAT SHIFTS MUCH
OF THE PRECIPITATION TO THE EAST OF THE AREA BY THE WEEKEND. THE
LATEST GFS AND ECMWF ENSEMBLES TEND TO FAVOR THIS APPROACH. AS A
RESULT...CURRENT FORECAST INCLUDES INCREASING SHOWER AND STORM
CHANCES THURSDAY NIGHT OVER THE WEST...PEAKING FRIDAY AND FRIDAY
EVENING...THEN DEPARTING SOUTHWEST INDIANA AND WESTERN KENTUCKY LATE
FRIDAY NIGHT AND EARLY SATURDAY.
IN THE WAKE OF THIS SYSTEM...COOLER WEATHER WILL RETURN NEXT WEEKEND
AS A NORTHWEST UPPER LEVEL FLOW PATTERN TAKES HOLD. HIGHS WILL DROP
BACK INTO THE 60S...WITH LOWS IN THE 40S BOTH WEEKEND DAYS. BOTH THE
15/12Z GFS AND ECMWF HINT AT THE POSSIBILITY FOR SOME VERY LIGHT
RAIN SATURDAY NIGHT AND SUNDAY. HOWEVER...GIVEN THE LOW CONFIDENCE
THAT FAR OUT...WILL KEEP CONDITIONS DRY FOR NOW.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 639 PM CDT SUN APR 15 2012
SOME ADJUSTMENTS IN TIMING FOR THE ONSET OF THE SHOWERS AND THUNDERSTORMS
FOR EACH OF THE WFO PAH TAF SITES WERE MADE WITH THE 00Z MONDAY
ROUTINE TAF ISSUANCE. ALSO...WITH THE ANTICIPATED OVERALL DOWNWARD
TREND OF THE ACTIVITY LATE THIS EVENING AND OVERNIGHT...ADJUSTED
VISIBILITIES IN THE THUNDERSTORMS UPWARD...BUT PROLONGED THE RAIN
SHIELD BEHIND THE LINE OF THUNDERSTORM A LITTLE LONGER. BETWEEN
08Z-13Z MONDAY...GRADUALLY RETURNED EACH OF THE TAF SITES BACK TO
VFR CONDITIONS FROM WEST TO EAST WITH TIME.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
UPDATE...SMITH
SHORT TERM...JP
LONG TERM....RP
AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS JACKSON KY
303 PM EDT SAT APR 14 2012
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 303 PM EDT SAT APR 14 2012
WE CONTINUE TO TRACK THE THREE MCS MOVING ACROSS THE OH VALLEY. THE
FIRST IS NOW OVER SE OH AND NE KY...AND HAS PASSED OUR FORECAST AREA.
THIS ONE CLIPPED THE NORTHERN PART OF OUR FORECAST AREA...WITH 0.02
INCHES OF RAIN AT THE BATH COUNTY AND ROWAN COUNTY MESONET SITES AND
0.08 INCHES AT THE FAIRVIEW IFLOWS SITE IN FLEMING COUNTY.
THE NEXT SYSTEM IN LINE NOW OVER SW OH...SE IN AND N KY MAY ALSO
AFFECT OUR FAR NORTHERN COUNTIES BETWEEN 20Z AND 22Z. THE TOPS OF
THIS MCS HAVE BEEN WARMING...LIGHTING HAS BEEN DECREASING...AS HAS
RADAR REFLECTIVITY. LATEST RADAR TRENDS SHOW THIS MAY ONLY CLIP
NORTHERN FLEMING COUNTY...SO ANY RAIN WILL LIKELY AFFECT LESS OF OUR
AREA THAN THE PREVIOUS SHOWERS.
THE REMNANTS OF THE THIRD MCS ARE OVER IL...AND THIS SYSTEM ALSO
DECREASING AT THIS TIME. BASED ON LATEST RADAR AND SATELLITE
TRENDS WILL ONLY CARRY THUNDER CHANCES FOR A COUPLE MORE HOURS IN THE
NORTH...THEN JUST GO ISOLATED SHOWERS IN THE FAR NORTH INTO THE
EARLY EVENING.
HEIGHTS WILL BE RISING AS THE UPPER RIDGE EXTENDING FROM THE GULF OF
MEXICO NORTH THROUGH THE OH VALLEY AMPLIFIES IN RESPONSE TO THE UPPER
LOW EMERGING FROM THE SOUTHERN ROCKIES. AT THE SURFACE THE WARM FRONT
DRAPED ACROSS THE LOWER OH VALLEY WILL MOVE NORTH...AND THE THREAT
OF CONVECTION WILL ALSO SHIFT NORTH...WITH ANY SHOWER CHANCES ONLY IN
THE FAR NORTH EARLY THIS EVENING.
ALL SHORT RANGE MODEL GUIDANCE IS IN AGREEMENT WITH THIS SCENARIO.
THE HRRR IS STILL TRYING TO BRING SOME SHOWERS ACROSS THE NORTHERN
PART OF OUR FORECAST AREA LATER THIS EVENING...BUT THIS IS NOT IN
AGREEMENT WITH CURRENT RADAR TRENDS AND LATEST MODEL GUIDANCE.
TEMPERATURES WILL WARM CONSIDERABLY ON SUNDAY AS RIDGE BUILDS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 303 PM EDT SAT APR 14 2012
THIS FORECAST BEGINS WITH AN APPROACHING 50H SHORT WAVE PUSHING
AGAINST A SUBSTANTIAL BERMUDA HIGH. THE HIGH PRESSURE WILL SLOW THE
PROGRESSION OF THE SHORT WAVE EVEN AS IT BEGINS TO FLATTEN THE HIGH.
LOOK FOR THE SHORT WAVE TO SPLIT AS IT APPROACHES THE ERN GREAT
LAKES WITH THE SRN PORTION REMAINING IN ERN TX. THIS WILL ELONGATE
THE ENERGY AND WEAKEN IT AS IT PASSES THRU ERN KY. STILL EXPECTING
LIKELY TSRA WITH THE FRONTAL PASSAGE ON MON AND EARLY MON NITE. THEN
THE ENERGY LEFT IN TX WILL FORM A SFC LOW IN THE WRN GULF AND SLOWLY
EDGE EAST WHILE CONTINUING TO PUSH WARM AND MOIST AIR INTO THE TN
VALLEY. THIS WILL KEEP THE THREAT FOR SCT SHRA/TSRA IN THE AREA BUT
HIGH PRESSURE BUILDING DOWN FROM THE GREAT LAKES SHOULD KEEP ANY
RAIN SOUTH OF THE KY/TN STATE LINE. MODELS INDICATE THAT THE FRONTAL
BNDRY WILL HANG UP ON THE SERN ATLANTIC COAST BUT EAST OF THE
APPALACHIAN MTNS FOR THE LATE WEEK PERIOD. THIS EVEN AS THE NEXT
WAVE FORMS ON THE LEE SIDE OF THE ROCKIES AND MOVES INTO THE CNTRL
PLAINS BY FRI. THIS WAVE WILL CROSS THE GREAT LAKES FRI NITE/SAT IN
A FASTER ZONAL FLOW AND DRAG ANOTHER FRONT THRU THE COMMONWEALTH
PROVIDING THE NEXT CHANCE FOR SCT SHRA/TSRA. TEMPS IN ADVANCE OF THE
STORMS ON MON WILL SOAR TO AROUND 80 BEFORE DROPPING INTO THE UPPER
50S MON NITE. THEN THE COOLER AIR WILL KEEP HIGHS ON TUE ONLY IN THE
MID 60S. AS THE ATMOSPHERE RECHARGES WITH THE SRLY INFLOW THRU THE
REST OF THE WEEK... EXPECT TEMPS TO SHOW A WARMING TREND INTO THE
UPPER 60S ON WED...LOWER 70S BY THU AND UPPER 70S FOR THE END OF THE
WORK WEEK. PRECIP ON FRI NIGHT AND SAT WILL ONCE AGAIN HOLD HIGHS TO
THE MID 60S FOR THE START OF THE WEEKEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 149 PM EDT SAT APR 14 2012
CONVECTION WILL AFFECT THE FAR NORTHERN PART OF THE FORECAST AREA
THIS AFTERNOON AS A WARM FRONT LIFTS NORTH THROUGH THE OH VALLEY.
SHOWERS AND THUNDERSTORMS WILL BRING LOCAL MVFR TO IFR CONDITIONS
MAINLY NORTH OF THE MOREHEAD AREA. ANY CONVECTION IN THE JACKSON
FORECAST AREA WILL END THIS EVENING.
ACROSS THE MAJORITY OF THE AREA...INCLUDING ALL TAF SITES...VFR
CONDITIONS WILL PREVAIL THROUGH THE DAY AND THROUGH THE REST OF THE
WEEKEND. GUSTY SOUTH TO SOUTH-SOUTHWEST WINDS WILL AFFECT THE SME AND
LOZ TAF SITES THIS AFTERNOON. GUSTY SOUTH-SOUTHWEST WINDS WILL AFFECT
THE ENTIRE FORECAST AREA SUNDAY AFTERNOON.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...SBH
LONG TERM....DUSTY
AVIATION...SBH
AREA FORECAST DISCUSSION
NWS JACKSON KY
150 PM EDT SAT APR 14 2012
.UPDATE...
ISSUED AT 149 PM EDT SAT APR 14 2012
STILL 3 DISTINCT MCS MOVING ACROSS THE OH VALLEY. THE FIRST IS NOW
AFFECTING S OH AND N KY...INCLUDING THE FAR N PART OF OUR FORECAST
AREA. THE SECOND...AND MOST VIGOROUS OF THE THREE...IS NOW MOVING
ACROSS INDIANA. THIS MAY CLIP THE NORTHERN PART OF OUR AREA DURING
THE LATE AFTERNOON. THE THIRD AND FINAL OF THE THREE IS OVER IL.
THERE IS A SLIGHT CHANCE THIS COULD BRING AN ISOLATED SHOWER TO THE
FAR N PART OF OUR AREA THIS EVENING.
ALL SHORT RANGE OPERATIONAL GUIDANCE IS IN AGREEMENT THAT RAIN
CHANCES WILL CONTINUE TO SHIFT NORTH. THE HRRR IS STILL INSISTENT ON
RAIN THREAT BEING FURTHER SOUTH. THE HRRR BRINGS THE REMNANTS OF THE
THIRD SYSTEM DESCRIBED ABOVE ACROSS THE NORTHERN HALF OF THE FORECAST
AREA BETWEEN 01Z AND 04Z...HOWEVER FEEL ONLY THE EXTREME NORTH HAS A
CHANCE OF BEING AFFECTED BY THIS.
HAVE UDPATED NDFD FOR LATEST NEAR TERM TRENDS. WILL ISSUE A COMPLETE
NEW FORECAST PACKAGE FOR ALL 7 DAYS AROUND 3 PM.
UPDATE ISSUED AT 1150 AM EDT SAT APR 14 2012
SATELLITE AND RADAR IMAGERY SHOW 3 DISTINCT MESOSCALE CONVECTIVE
SYSTEMS OR REMNANTS OF MCS. THE FIRST IN THE LINE IS CENTERED OVER
SW OH...SE IN AND N KY. THE SOUTHERN EDGE OF THIS COMPLEX...WHICH
DOES HAVE SOME LIGHTNING IN IT WILL AFFECT THE FAR NORTHERN PART OF
OUR FORECAST AREA OVER THE NEXT COUPLE OF HOURS. THE NEXT SYSTEM IS
CURRENTLY ALONG THE IN IL BORDER AND THE THIRD IN LINE IS OVER SOUTH
CENTRAL MO.
THE MAIN FORECAST CHALLENGE IS HOW FAR SOUTH ANY SHOWERS AND
THUNDERSTORMS WILL EXTEND WITH EACH SYSTEM. THE 12Z NAM AND RUC SEEM
TO HAVE THE ACTIVITY SLIGHTLY TOO FAR NORTH...NOT BY MUCH...BUT A
SLIGHT DIFFERENCE IS IMPORTANT FOR THE NORTHERN PART OF OUR FORECAST AREA.
THE HIGH RESOLUTION RAPID REFRESH...HRRR....HAS BEEN HANDLING THE
CONVECTION FAIRLY WELL...BUT IS TOO FAR SOUTH. A SOLUTION IN BETWEEN
THE OPERATIONAL MODELS AND THE HRRR SEEMS TO BE BEST AT THIS TIME.
THE MCS HAVE BEEN MOVING ENE...FOLLOWING THE BACK SIDE OF THE UPPER
RIDGE EXTENDING FROM THE GULF OF MEXICO N ALONG THE WESTERN SIDE OF
THE APPALACHIANS. THIS RIDGE WILL BUILD...WITH RISING HEIGHTS OVER
ERN KY...IN RESPONSE TO THE UPPER LOW EMERGING FROM THE SOUTHWEST
UNITED STATES. AS A RESULT THE CONVECTION THREAT WILL GRADUALLY
SHIFT NORTH OVER THE NEXT 12 HOURS. MAY NEED TO HOLD ONTO A SHOWER
AND THUNDERSTORM CHANCE A LITTLE LONGER INTO THE EVENING OVER THE FAR
NORTHERN PART OF THE FORECAST AREA...BUT WILL HOLD OFF ON THAT FOR
NOW.
HAVE UPDATED THE NDFD AND ASSOCIATED PRODUCTS BASED ON LATEST
OBSERVATIONAL AND MODEL TRENDS.
UPDATE ISSUED AT 851 AM EDT SAT APR 14 2012
HAVE UPDATED NDFD AND ASSOCIATED PRODUCTS TO ACCOUNT FOR ISOLATED
SHOWER ACTIVITY ACROSS THE SOUTHERN PART OF THE FORECAST AREA. THIS
IS VERY LIGHT...BUT NOTE 0.01 WAS RECORDED AT THE OWSLEY COUNTY
MESONET STATION JUST BEFORE 8 AM...AND SIMILAR RADAR RETURNS EXTEND
AS FAR SOUTH AS BELL COUNTY. HAVE ALSO UPDATED HOURLY NDFD BASED ON
LATEST SURFACE AND SATELLITE OBSERVATIONAL TRENDS.
UPDATE ISSUED AT 700 AM EDT SAT APR 14 2012
UPDATED THE FORECAST PACKAGE BASED ON REGIONAL RADAR COMPOSITE.
SCATTERED SHOWERS ARE DEVELOPING UPSTREAM NOW. LATEST TRENDS SUGGEST
A BETTER COVERAGE OF SHOWER ACTIVITY...AND POSSIBLY REACHING A BIT
FURTHER SOUTH THAN ANTICIPATED. MADE SOME ADJUSTMENTS TO POPS...
GENERALLY INCREASING THEM SLIGHTLY IN THE NORTH AND EXPANDING THEM
SLIGHTLY SOUTHWARD. OTHERWISE...MADE MINOR TWEAKS GRIDS FOR LATEST
HOURLY TRENDS IN TEMPS AND DEW POINTS.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 344 AM EDT SAT APR 14 2012
THE BAND OF SHOWERS ACROSS THE SOUTHERN PORTIONS OF THE CWA THAT WAS
ASSOCIATED WITH A BOUNDARY HAS ALL BUT DISSIPATED. AFTER A CLOSER
LOOK...THIS BOUNDARY IS PROBABLY THE WARM FRONT THAT WE HAVE BEEN
ANTICIPATING. WINDS ARE VEERING OUT OF THE SOUTH BEHIND IT AND SFC
DEW POINTS ARE ON THE RISE FROM WEST TO EAST. ADDITIONAL ISOLD SHOWER
ACTIVITY IS NOW FIRING ACROSS THE NORTH AND EAST AS THE BOUNDARY
CONTINUES TO PUSH EASTWARD. EXPENDED ISOLD POPS THROUGH THE EASTERN
PORTIONS OF THE CWA...COVERING WHAT REMAINS OF THE OVERNIGHT PERIOD.
AGAIN...BASED ON SFC OBS MOST ACTIVITY THROUGH DAWN WILL RESULT IN
NOTHING MORE THAN A BRIEF LIGHT RAIN THAT JUST WETS THE GROUND. ONLY
A FEW LOCATIONS WILL ACTUALLY MEASURE...WHERE THE STRONGEST SHOWERS
PASS.
NEXT FEATURE IS COMPLEX OF STORMS THAT WILL ROLL ACROSS THE OHIO
VALLEY TODAY. SHOWERS AND THUNDERSTORMS WILL CONTINUE TO EXPAND
EASTWARD FROM IL INTO IN THIS MORNING...AND EVENTUALLY THROUGH OHIO.
WHILE MOST OF THE ENERGY AND DYNAMICS ASSOCIATED WITH THIS SYSTEM
WILL REMAIN TO OUR NORTH...MODELS AND GUIDANCE SUGGEST IT WILL BE
CLOSE ENOUGH THAT SOME SCATTERED SHOWER ACTIVITY CAN NOT BE RULED OUT
ACROSS OUR NORTHERN MOST COUNTIES. INCREASED POPS A BIT ACROSS THE
EXTREME NORTH AND TAPERED SOUTHWARD FROM THERE. THIS PUTS THE MOST
LIKELY AREAS TO SEE RAIN TODAY GENERALLY ALONG AND NORTH OF THE
INTERSTATE 64 CORRIDOR. SCATTERED TO ISOLD SHOWERS WILL BE POSSIBLE
SOUTHWARD TO THE HAL ROGERS PARKWAY...THOUGH EXPECT MOST IF ANY
ADDITIONAL ACTIVITY WILL REMAIN NORTH OF THE MOUNTAIN PARKWAY. DO NOT
SEE MUCH IF ANYTHING SOUTH OF HAL ROGERS. WHILE INSTABILITY LOOKS
MARGINAL AT BEST CAN NOT RULE OUT A FEW RUMBLES OF THUNDER. SO WILL
CONTINUE TO MENTION THUNDER IN THE FORECAST.
NO MAJOR CHANGES TO TEMPS. ALTHOUGH WE WILL BE IN THE WARM SECTOR
NOW...CLOUDS AND ANY PRECIPITATION WE MANAGE TO SEE WILL HELP KEEP
TEMPERATURES A BIT LOWER TODAY. BUT DECENT RIDGING ALOFT...CLEARING
SKIES AND A STRONG SOUTHERLY GRADIENT WILL DRIVE TEMPS UP INTO THE
80S SUNDAY. CONSEQUENTLY BUMPED TEMPS UP JUST A TAD SUNDAY.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 344 AM EDT SAT APR 14 2012
THE MODELS START OUT IN GOOD AGREEMENT WITH AN UPPER RIDGE EXTENDING
FROM A HIGH JUST EAST OF THE FL/GA BORDER...ACROSS THE CAROLINA AND
THEN BISECTING PA AND NY. THERE WILL BE AN UPPER TROUGH EXTENDING
FROM AN UPPER LOW NEAR SIOUX CITY AND THEN EXTENDING SOUTH ACROSS
THE OK AND TX PANHANDLES. AT THE SURFACE...A LOW IS FORECAST TO BE
OVER WS WITH A COLD FRONT EXTENDING SOUTH ACROSS ST LOUIS TO
ARKLATEX. THE FRONT AND UPPER TROUGH ARE FORECAST TO MOVE TO THE
EAST AND THE BIG QUESTION IS WHEN WILL THE FRONT MOVE ACROSS EASTERN
KENTUCKY. THE GFS HAS THE FRONT MOVING ACROSS EASTERN KENTUCKY ON
MONDAY AFTERNOON...WHILE THE ECMWF HAS THE FRONT MOVING ACROSS THE
AREA ON MONDAY EVENING. AROUND HERE...A GENERAL RULE OF THUMB WHEN
SYSTEMS ARE TRYING TO MOVE INTO AN UPPER RIDGE...IS SLOWER IS
BETTER. WITH THIS IN MIND...WILL SLOW THE FRONT DOWN A LITTLE. ONCE
THIS SYSTEM MOVES THROUGH THE AREA...THE UPPER PATTERN WILL BE
TRANSITIONING TO A MORE ZONAL PATTERN. THE MODELS ARE IN MUCH BETTER
THAN AVERAGE AGREEMENT THROUGH WEDNESDAY. THE FORECAST CHALLENGE FOR
A ZONAL PATTERN IS THAT SYSTEMS MOVE PRETTY FAST...AND SO TIMING OF
THE PRECIPITATION CAN BECOME DIFFICULT...HOWEVER THE TEMPERATURES
BECOME MORE CERTAIN AS THERE ARE NOT SUCH BIG SWINGS AS A FRONT
MOVES ACROSS THE AREA. THE LEADING EDGE OF THE NEXT SYSTEM SHOULD
START EFFECTING THE AREA ON FRIDAY...WITH SOME ISOLATED SHOWERS AND
THUNDERSTORMS IN THE FORECAST. THE MAIN FRONT SHOULD BE MOVING
THROUGH THE AREA ON SATURDAY. FOR TEMPERATURES...ONLY MADE SOME
SLIGHT CHANGES TO REFLECT THE CURRENT MODEL CONSENSUS TRENDS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 149 PM EDT SAT APR 14 2012
CONVECTION WILL AFFECT THE FAR NORTHERN PART OF THE FORECAST AREA
THIS AFTERNOON AS A WARM FRONT LIFTS NORTH THROUGH THE OH VALLEY.
SHOWERS AND THUNDERSTORMS WILL BRING LOCAL MVFR TO IFR CONDITIONS
MAINLY NORTH OF THE MOREHEAD AREA. ANY CONVECTION IN THE JACKSON
FORECAST AREA WILL END THIS EVENING.
ACROSS THE MAJORITY OF THE AREA...INCLUDING ALL TAF SITES...VFR
CONDITIONS WILL PREVAIL THROUGH THE DAY AND THROUGH THE REST OF THE
WEEKEND. GUSTY SOUTH TO SOUTH-SOUTHWEST WINDS WILL AFFECT THE SME AND
LOZ TAF SITES THIS AFTERNOON. GUSTY SOUTH-SOUTHWEST WINDS WILL AFFECT
THE ENTIRE FORECAST AREA SUNDAY AFTERNOON.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SBH
SHORT TERM...RAY
LONG TERM....JJ
AVIATION...SBH
AREA FORECAST DISCUSSION
NWS JACKSON KY
1150 AM EDT SAT APR 14 2012
.UPDATE...
ISSUED AT 1150 AM EDT SAT APR 14 2012
SATELLITE AND RADAR IMAGERY SHOW 3 DISTINCT MESOSCALE CONVECTIVE
SYSTEMS OR REMNANTS OF MCS. THE FIRST IN THE LINE IS CENTERED OVER
SW OH...SE IN AND N KY. THE SOUTHERN EDGE OF THIS COMPLEX...WHICH
DOES HAVE SOME LIGHTNING IN IT WILL AFFECT THE FAR NORTHERN PART OF
OUR FORECAST AREA OVER THE NEXT COUPLE OF HOURS. THE NEXT SYSTEM IS
CURRENTLY ALONG THE IN IL BORDER AND THE THIRD IN LINE IS OVER SOUTH
CENTRAL MO.
THE MAIN FORECAST CHALLENGE IS HOW FAR SOUTH ANY SHOWERS AND
THUNDERSTORMS WILL EXTEND WITH EACH SYSTEM. THE 12Z NAM AND RUC SEEM
TO HAVE THE ACTIVITY SLIGHTLY TOO FAR NORTH...NOT BY MUCH...BUT A
SLIGHT DIFFERENCE IS IMPORTANT FOR THE NORTHERN PART OF OUR FORECAST AREA.
THE HIGH RESOLUTION RAPID REFRESH...HRRR....HAS BEEN HANDLING THE
CONVECTION FAIRLY WELL...BUT IS TOO FAR SOUTH. A SOLUTION IN BETWEEN
THE OPERATIONAL MODELS AND THE HRRR SEEMS TO BE BEST AT THIS TIME.
THE MCS HAVE BEEN MOVING ENE...FOLLOWING THE BACK SIDE OF THE UPPER
RIDGE EXTENDING FROM THE GULF OF MEXICO N ALONG THE WESTERN SIDE OF
THE APPALACHIANS. THIS RIDGE WILL BUILD...WITH RISING HEIGHTS OVER
ERN KY...IN RESPONSE TO THE UPPER LOW EMERGING FROM THE SOUTHWEST
UNITED STATES. AS A RESULT THE CONVECTION THREAT WILL GRADUALLY
SHIFT NORTH OVER THE NEXT 12 HOURS. MAY NEED TO HOLD ONTO A SHOWER
AND THUNDERSTORM CHANCE A LITTLE LONGER INTO THE EVENING OVER THE FAR
NORTHERN PART OF THE FORECAST AREA...BUT WILL HOLD OFF ON THAT FOR
NOW.
HAVE UPDATED THE NDFD AND ASSOCIATED PRODUCTS BASED ON LATEST
OBSERVATIONAL AND MODEL TRENDS.
UPDATE ISSUED AT 851 AM EDT SAT APR 14 2012
HAVE UPDATED NDFD AND ASSOCIATED PRODUCTS TO ACCOUNT FOR ISOLATED
SHOWER ACTIVITY ACROSS THE SOUTHERN PART OF THE FORECAST AREA. THIS
IS VERY LIGHT...BUT NOTE 0.01 WAS RECORDED AT THE OWSLEY COUNTY
MESONET STATION JUST BEFORE 8 AM...AND SIMILAR RADAR RETURNS EXTEND
AS FAR SOUTH AS BELL COUNTY. HAVE ALSO UPDATED HOURLY NDFD BASED ON
LATEST SURFACE AND SATELLITE OBSERVATIONAL TRENDS.
UPDATE ISSUED AT 700 AM EDT SAT APR 14 2012
UPDATED THE FORECAST PACKAGE BASED ON REGIONAL RADAR COMPOSITE.
SCATTERED SHOWERS ARE DEVELOPING UPSTREAM NOW. LATEST TRENDS SUGGEST
A BETTER COVERAGE OF SHOWER ACTIVITY...AND POSSIBLY REACHING A BIT
FURTHER SOUTH THAN ANTICIPATED. MADE SOME ADJUSTMENTS TO POPS...
GENERALLY INCREASING THEM SLIGHTLY IN THE NORTH AND EXPANDING THEM
SLIGHTLY SOUTHWARD. OTHERWISE...MADE MINOR TWEAKS GRIDS FOR LATEST
HOURLY TRENDS IN TEMPS AND DEW POINTS.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 344 AM EDT SAT APR 14 2012
THE BAND OF SHOWERS ACROSS THE SOUTHERN PORTIONS OF THE CWA THAT WAS
ASSOCIATED WITH A BOUNDARY HAS ALL BUT DISSIPATED. AFTER A CLOSER
LOOK...THIS BOUNDARY IS PROBABLY THE WARM FRONT THAT WE HAVE BEEN
ANTICIPATING. WINDS ARE VEERING OUT OF THE SOUTH BEHIND IT AND SFC
DEW POINTS ARE ON THE RISE FROM WEST TO EAST. ADDITIONAL ISOLD SHOWER
ACTIVITY IS NOW FIRING ACROSS THE NORTH AND EAST AS THE BOUNDARY
CONTINUES TO PUSH EASTWARD. EXPENDED ISOLD POPS THROUGH THE EASTERN
PORTIONS OF THE CWA...COVERING WHAT REMAINS OF THE OVERNIGHT PERIOD.
AGAIN...BASED ON SFC OBS MOST ACTIVITY THROUGH DAWN WILL RESULT IN
NOTHING MORE THAN A BRIEF LIGHT RAIN THAT JUST WETS THE GROUND. ONLY
A FEW LOCATIONS WILL ACTUALLY MEASURE...WHERE THE STRONGEST SHOWERS
PASS.
NEXT FEATURE IS COMPLEX OF STORMS THAT WILL ROLL ACROSS THE OHIO
VALLEY TODAY. SHOWERS AND THUNDERSTORMS WILL CONTINUE TO EXPAND
EASTWARD FROM IL INTO IN THIS MORNING...AND EVENTUALLY THROUGH OHIO.
WHILE MOST OF THE ENERGY AND DYNAMICS ASSOCIATED WITH THIS SYSTEM
WILL REMAIN TO OUR NORTH...MODELS AND GUIDANCE SUGGEST IT WILL BE
CLOSE ENOUGH THAT SOME SCATTERED SHOWER ACTIVITY CAN NOT BE RULED OUT
ACROSS OUR NORTHERN MOST COUNTIES. INCREASED POPS A BIT ACROSS THE
EXTREME NORTH AND TAPERED SOUTHWARD FROM THERE. THIS PUTS THE MOST
LIKELY AREAS TO SEE RAIN TODAY GENERALLY ALONG AND NORTH OF THE
INTERSTATE 64 CORRIDOR. SCATTERED TO ISOLD SHOWERS WILL BE POSSIBLE
SOUTHWARD TO THE HAL ROGERS PARKWAY...THOUGH EXPECT MOST IF ANY
ADDITIONAL ACTIVITY WILL REMAIN NORTH OF THE MOUNTAIN PARKWAY. DO NOT
SEE MUCH IF ANYTHING SOUTH OF HAL ROGERS. WHILE INSTABILITY LOOKS
MARGINAL AT BEST CAN NOT RULE OUT A FEW RUMBLES OF THUNDER. SO WILL
CONTINUE TO MENTION THUNDER IN THE FORECAST.
NO MAJOR CHANGES TO TEMPS. ALTHOUGH WE WILL BE IN THE WARM SECTOR
NOW...CLOUDS AND ANY PRECIPITATION WE MANAGE TO SEE WILL HELP KEEP
TEMPERATURES A BIT LOWER TODAY. BUT DECENT RIDGING ALOFT...CLEARING
SKIES AND A STRONG SOUTHERLY GRADIENT WILL DRIVE TEMPS UP INTO THE
80S SUNDAY. CONSEQUENTLY BUMPED TEMPS UP JUST A TAD SUNDAY.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 344 AM EDT SAT APR 14 2012
THE MODELS START OUT IN GOOD AGREEMENT WITH AN UPPER RIDGE EXTENDING
FROM A HIGH JUST EAST OF THE FL/GA BORDER...ACROSS THE CAROLINA AND
THEN BISECTING PA AND NY. THERE WILL BE AN UPPER TROUGH EXTENDING
FROM AN UPPER LOW NEAR SIOUX CITY AND THEN EXTENDING SOUTH ACROSS
THE OK AND TX PANHANDLES. AT THE SURFACE...A LOW IS FORECAST TO BE
OVER WS WITH A COLD FRONT EXTENDING SOUTH ACROSS ST LOUIS TO
ARKLATEX. THE FRONT AND UPPER TROUGH ARE FORECAST TO MOVE TO THE
EAST AND THE BIG QUESTION IS WHEN WILL THE FRONT MOVE ACROSS EASTERN
KENTUCKY. THE GFS HAS THE FRONT MOVING ACROSS EASTERN KENTUCKY ON
MONDAY AFTERNOON...WHILE THE ECMWF HAS THE FRONT MOVING ACROSS THE
AREA ON MONDAY EVENING. AROUND HERE...A GENERAL RULE OF THUMB WHEN
SYSTEMS ARE TRYING TO MOVE INTO AN UPPER RIDGE...IS SLOWER IS
BETTER. WITH THIS IN MIND...WILL SLOW THE FRONT DOWN A LITTLE. ONCE
THIS SYSTEM MOVES THROUGH THE AREA...THE UPPER PATTERN WILL BE
TRANSITIONING TO A MORE ZONAL PATTERN. THE MODELS ARE IN MUCH BETTER
THAN AVERAGE AGREEMENT THROUGH WEDNESDAY. THE FORECAST CHALLENGE FOR
A ZONAL PATTERN IS THAT SYSTEMS MOVE PRETTY FAST...AND SO TIMING OF
THE PRECIPITATION CAN BECOME DIFFICULT...HOWEVER THE TEMPERATURES
BECOME MORE CERTAIN AS THERE ARE NOT SUCH BIG SWINGS AS A FRONT
MOVES ACROSS THE AREA. THE LEADING EDGE OF THE NEXT SYSTEM SHOULD
START EFFECTING THE AREA ON FRIDAY...WITH SOME ISOLATED SHOWERS AND
THUNDERSTORMS IN THE FORECAST. THE MAIN FRONT SHOULD BE MOVING
THROUGH THE AREA ON SATURDAY. FOR TEMPERATURES...ONLY MADE SOME
SLIGHT CHANGES TO REFLECT THE CURRENT MODEL CONSENSUS TRENDS.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 735 AM EDT SAT APR 14 2012
A WEAK UPPER LEVEL DISTURBANCE ASSOCIATED WITH A WARM FRONTAL
BOUNDARY WILL BRING SHOWER ACTIVITY TO MAINLY THE NORTHERN HALF OF
THE CWA LATER TODAY. THEREFORE CARRIED VCSH FOR JKL THIS AFTERNOON.
CIGS AND VSBY REMAIN IN VFR RANGE BUT EXPECT OCCASIONAL CIGS BETWEEN
5K AND 9K FT WILL BE PREDOMINANT THROUGH THE TAF FORECAST PERIOD.
GRADIENT WINDS WILL PICK UP FROM THE SOUTHWEST AROUND 10 KTS THIS
AFTERNOON... WITH SOME GUSTS AROUND 15KT FOR GOOD MEASURE. SOME LLWS
IS EXPECTED UNTIL THE INVERSION BREAKS AROUND 14Z.
&&
.JKL WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...SBH
SHORT TERM...RAY
LONG TERM....JJ
AVIATION...JJ
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
934 PM CDT SUN APR 15 2012
.UPDATE...
LINE OF SHOWERS AND A FEW STRONG THUNDERSTORMS BECOMING A BIT MORE
ORGANIZED OVER EASTERN TEXAS ALONG SURFACE BOUNDARY. WATER VAPOR
IMAGERY SHOWS AN UPPER LEVEL LOW OVER THE UPPER MIDWEST WITH AN
UPPER LEVEL DISTURBANCE AND JET STREAK SWINGING AROUND IT AND OUT
OF THE SOUTHWEST U.S. THIS DISTURBANCE WILL BEGIN TO ENHANCE UPPER
LEVEL DIVERGENCE AND PLACE THE FORECAST AREA IN A MORE FAVORABLE
RIGHT ENTRANCE REGION OF JET OVERNIGHT...AND HELP KICK THE SURFACE
BOUNDARY SLOWLY TO THE EAST...WITH BEST DEVELOPMENT OF
THUNDERSTORM ACTIVITY ALONG THE LINE NOTED AROUND AND AFTER
16/09Z.
LIKE THE LATEST RUC HANDLING OF THE CONVECTION AND WILL USE A
COMBO OF THE 16/00Z RUC AND NAM12 FOR THE REMAINDER OF THE NIGHT.
IN THIS SCENARIO...BEST CHANCE OF RAIN WILL BE WEST OF AN
ALEXANDRIA TO LAKE CHARLES LINE...AND WILL HAVE LIKELY POPS IN
THESE AREAS...TAPERING TO CHANCE OVER ACADIANA...MAINLY FOR SOME
STRAY SHOWERS DEVELOPING AHEAD OF THE LINE OFF THE GULF AND INTO
SOUTH CENTRAL LOUISIANA BEFORE DAYBREAK. SEVERE THREAT SEEMS TO
BECOMING MORE LIMITED...WITH MARGINAL LOW LEVEL INSTABILITY...
HOWEVER MAYBE SOME ISOLATED STRONG WIND GUSTS OR HAIL...AND
FREQUENT LIGHTNING WILL STILL BE POSSIBLE. PRECIPITABLE WATER ON
LATEST KLCH SOUNDING WAS AT 1.5 INCHES AND IS EXPECTED TO CONTINUE
TO INCREASE. THUS...WITH THE EXPECTED SLOW MOVEMENT OF THE SURFACE
BOUNDARY...SOME LOCALLY HEAVY RAINFALL WILL BE POSSIBLE AND WILL
KEEP MENTION OF THAT IN THE WEATHER GRIDS. RAINFALL RATES AROUND 2
INCHES PER HOUR WILL BE POSSIBLE WITH THE STORMS ALONG THE LINE.
FOR THE COASTAL WATERS...GRADIENT BEGINNING TO RELAX SOME. SMALL
CRAFT ADVISORY IS EXPECTED TO CONTINUE THROUGH-OUT THE NIGHT INTO
MONDAY NIGHT FOR THE OUTER WATERS...AS IT WILL TAKE SOME TIME FOR
THE SEAS TO FALL BELOW 7 FEET.
RUA
&&
.PREV DISCUSSION... /ISSUED 727 PM CDT SUN APR 15 2012/
UPDATE...
HAVE UPDATED FORECAST TO REMOVE WIND ADVISORY HEADLINE. WIND
ADVISORY WAS ALLOWED TO EXPIRE AT 7 PM CDT AS SUSTAINED SOUTHERLY
WINDS HAVE DECREASED TO BELOW 20 MPH.
UPPER AIR SOUNDING FROM KLCH AT 16/00Z SHOWS AN INCREASE IN
MOISTURE WITH PRECIPITABLE WATER NOW UP TO 1.5 INCHES COMPARED TO
0.9 INCHES 12 HOURS AGO. CAP HAS ALSO WEAKENED...BUT STILL ENOUGH
TO KEEP THUNDERSTORM ACTIVITY IN CHECK. SCATTERED ACTIVITY
SKIRTING THE WESTERN PORTIONS OF THE FORECAST AREA...WHERE SURFACE
BOUNDARY HAS PROVIDED ENOUGH LIFT TO GET SOME ACTIVITY GOING. AT
THE PRESENT...NAM12 SEEMS TO BE HAVING A BETTER HANDLE ON
CONVECTION THAN OTHER MODELS. ALTHOUGH...RIGHT ENTRANCE REGION OF
JET IS EXPECTED TO NEAR FORECAST AREA OVERNIGHT...WHICH MAY BE
WHAT IS NEEDED TO GET CONVECTION INITIATED AND MORE ORGANIZED...WHICH
IS WHAT OTHER GUIDANCE IS BANKING ON. IF CURRENT TRENDS CONTINUE...MAY
HAVE TO ADJUST POPS DOWNWARD EAST OF A LAKE CHARLES TO LEESVILLE
LINE FOR THE OVERNIGHT PERIOD. AT THIS POINT...WITH INCREASING
MOISTURE CONTENT...AND EXPECTED SLOW MOVEMENT OF SURFACE BOUNDARY...HEAVY
RAINFALL MAY BE THE BIGGEST CONCERN LATER ON TONIGHT INTO MONDAY.
RUA
PREV DISCUSSION... /ISSUED 622 PM CDT SUN APR 15 2012/
DISCUSSION...
00Z TAF ISSUANCE.
AVIATION...
SHRA/TSRA BEGINNING TO INCREASE JUST WEST OF THE REGION...APPROACHING
LFK. SCT SHRA/TSRA WILL BE POSSIBLE FURTHER E ACROSS SE TX/C AND
SW LA BY 02-04Z...AND ACROSS SC LA BY 04-06Z. EXPECTING THE
STRONGEST TSRA POSSIBLE BETWEEN 04-08Z FOR AEX/BPT/LCH...AND
08-12Z FOR LFT/ARA. FOR THIS...PLACED TEMPO GROUPS FOR TSRA ALONG
WITH IFR CEILINGS/VSBY DURING THESE TIME PERIODS. FOR THE
REMAINDER OF THE FORECAST PERIOD...THE BOUNDARY IS EXPECTING TO
STALL ACROSS SE TX THRU C LA...YIELDING SHRA WITH INTERMITTENT
TSRA DURING THIS TIME.
DML
PREV DISCUSSION... /ISSUED 448 PM CDT SUN APR 15 2012/
SYNOPSIS...
WATER VAPOR AND UPPER AIR ANALYSIS SHOWS DEEP TROF LIFTING INTO
THE CNTL PLAINS. A SFC COLD FRONT ASSOCIATED WITH THIS SYSTEM
EXTENDED FM THE CNTL CONUS SOUTHWARD INTO TX...ALONG ROUGHLY A
PARIS TO GONZALES LINE. DIVERGENCE ALOFT IN CONJUNCTION WITH LOW
LEVEL FORCING ASSOCIATED WITH THE FRONT ARE PRODUCING AN
EXTENSIVE BAND OF SHOWERS AND THUNDERSTORMS FROM THE MID MS VALLEY
SOUTH INTO SE TX. RECENT RADAR TRENDS INDICATE SCT SHOWERS
DEVELOPING IN THE WARM MOIST AIRMASS ACRS SE TX INTO SW LA AHEAD
OF THIS LINE.
DISCUSSION...
THIS POTENT SYSTEM WILL CONTINUE TO MOVE EAST TONIGHT...BRINGING
THE COLD FRONT TO THE SABINE RIVER VALLEY BY EARLY MONDAY MORNING.
THERE IS STILL A SLIGHT RISK FOR SEVERE WEATHER ACRS SE TX INTO
WRN LA THIS EVENING...WITH AFTN HEATING CONTRIBUTING TO THE
DESTABILIZATION OF THE ATMOSPHERE. THE POTENTIAL FOR STRONG TO
SEVERE THUNDERSTORMS WILL SHIFT INTO CNTL AND SW LA AFTER
MIDNIGHT TONIGHT AS ADEQUATE DEEP LAYER SHEAR REMAINS IN PLACE
WITH INSTABILITY BECOMING MARGINAL. THE GREATEST THREAT WILL BE
DUE TO DAMAGING WINDS...ALTHOUGH HAIL AND ISOLATED TORNADOES
CANNOT BE RULED OUT ENTIRELY.
THE BIGGER CONCERN HOWEVER REMAINS THE POTENTIAL FOR HEAVY
RAINFALL TONIGHT INTO MONDAY. ABUNDANT MOISTURE OVER THE AREA WITH
PW VALUES APPROACHING 1.7 INCHES ON MONDAY WILL RESULT IN
EFFICIENT RAIN RATES IN SOME STORMS. THE SFC FRONT IS EXPECTED TO
STALL NR THE COAST OR OVER THE NRN GULF ON MONDAY...WITH AN
INVERTED TROF DEVELOPING ALONG IT MONDAY NIGHT. THIS WILL SERVE AS
A FOCUS FOR ADDITIONAL RAINFALL DEVELOPMENT MONDAY AFTN INTO
MONDAY NIGHT. AREAL RAINFALL TOTALS FROM TONIGHT THROUGH TUESDAY
WILL RANGE BETWEEN 2-4 INCHES...ALTHOUGH LOCALIZED HIGHER AMOUNTS
WILL BE POSSIBLE. AT THIS TIME...DO NOT SEE PRECIP TOTALS
EXCEEDING FLASH FLOOD GUIDANCE DURING THE PERIOD...ALTHOUGH
ISOLATED AREAS COULD APPROACH THESE VALUES SHOULD TRAINING STORMS
DEVELOP OVER THE AREA.
THE SFC LOW/FRONT WILL FINALLY SLIDE EAST TUESDAY AS THE UPPER
TROF AXIS CROSSES THE LOWER MS VALLEY. THIS WILL BRING DRIER AIR
INTO THE AREA. MORNING LOWS WILL BE MORE SEASONABLE WHILE AFTN HIGHS
WILL CLIMB INTO THE LOWER 80S. ANOTHER SYSTEM IS FCST TO MOVE
THROUGH THE AREA FRIDAY INTO SATURDAY...BRINGING ANOTHER CHANCE
FOR RAIN AND SLIGHTLY COOLER TEMPERATURES BY NEXT WEEKEND.
MARINE...
THE COMBINATION OF PERSISTENT HIGH PRESSURE TO OUR EAST AND
DEEPENING LOW PRESSURE OVER THE PLAINS STATES WILL KEEP A
STRONG ONSHORE FLOW OVER THE COASTAL WATERS. SMALL CRAFT ADVISORY
CONDITIONS WILL PERSIST OVER THE COASTAL WATERS THROUGH EARLY
MONDAY. SOUTHERLY WINDS WILL DIMINISH MONDAY MORNING AS A COLD
FRONT ADVANCES TOWARD THE REGION...WITH THE BOUNDARY ADVANCING
INTO THE WESTERN GULF MONDAY THEN BRIEFLY SLOWING OR STALLING.
NUMEROUS SHOWERS AND THUNDERSTORMS WILL ACCOMPANY THE FRONT FOR
THE BEGINNING OF THE WORK-WEEK. THE FRONT WILL FINALLY EXIT EAST
ON TUESDAY WITH OFFSHORE FLOW EXPECTED TUESDAY INTO WEDNESDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
KLCH 72 79 64 79 59 / 50 80 60 30 10
KBPT 71 79 66 80 61 / 60 80 50 30 10
KAEX 68 79 62 79 57 / 50 60 50 30 10
KLFT 72 82 65 79 60 / 30 70 60 50 20
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 1 PM CDT MONDAY FOR THE FOLLOWING
ZONES: WATERS FROM INTRACOASTAL CITY TO CAMERON LA FROM 20
TO 60 NM...WATERS FROM CAMERON LA TO HIGH ISLAND TX FROM 20
TO 60 NM...WATERS FROM LOWER ATCHAFALAYA RIVER TO
INTRACOASTAL CITY LA FROM 20 TO 60 NM.
SMALL CRAFT ADVISORY UNTIL 1 AM CDT MONDAY FOR THE FOLLOWING
ZONES: COASTAL WATERS FROM CAMERON LA TO HIGH ISLAND TX OUT
20 NM...COASTAL WATERS FROM INTRACOASTAL CITY TO CAMERON LA
OUT 20 NM...COASTAL WATERS FROM LOWER ATCHAFALAYA RIVER TO
INTRACOASTAL CITY LA OUT 20 NM.
SMALL CRAFT EXERCISE CAUTION FROM 1 AM TO 7 AM CDT MONDAY FOR
THE FOLLOWING ZONES: COASTAL WATERS FROM CAMERON LA TO HIGH
ISLAND TX OUT 20 NM...COASTAL WATERS FROM INTRACOASTAL CITY
TO CAMERON LA OUT 20 NM...COASTAL WATERS FROM LOWER
ATCHAFALAYA RIVER TO INTRACOASTAL CITY LA OUT 20 NM.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1055 PM EDT SUN APR 15 2012
.SYNOPSIS...
ISSUED AT 355 PM EDT SUN APR 15 2012
A STRONG COLD FRONT WILL CROSS SOUTHWEST LOWER MICHIGAN OVERNIGHT.
IT WILL ACCOMPANIED BY A LINE OF THUNDERSTORMS WITH GUSTY WINDS.
TEMPERATURES WILL FALL DURING MONDAY WITH GUSTY WINDS. EARLY MORNING
SHOWERS AND THUNDERSTORMS WILL GIVE WAY TO SCATTERED AFTERNOON
SHOWERS. THOSE COULD BE MIXED WITH WET SNOW OVER NORTHWEST
SECTIONS BY LATE AFTERNOON. SPRINKLES AND FLURRIES WILL END MONDAY
NIGHT AND THAT WILL LEAD TO CLEARING SKIES WITH FROST AND FREEZING
TEMPERATURES. A QUICK MOVING SYSTEM WILL BRING MORE SHOWERS TO THE
AREA WEDNESDAY.
&&
.UPDATE...
ISSUED AT 1055 PM EDT SUN APR 15 2012
WE HAVE ISSUED AN UPDATE THIS EVENING...MAINLY TO BUMP POPS UP TO
THE 90-100 PCT CATEGORY. AXIS OF BEST MOISTURE AHEAD OF THE FRONT IS
NOW LEANING INTO THE AREA FROM THE WEST. MOST LOCATIONS WILL GET
MEASURABLE PCPN BASED OFF OF THE COVERAGE OF PCPN TO OUR SOUTH
AND WEST. THIS ALL OCCURS AS THE STRONG LLJ AHEAD OF THE SYSTEM
WILL FEED STRONG MOISTURE TRANSPORT INTO THE AREA.
SEVERE THREAT IS QUITE LIMITED MAINLY DUE TO THE LACK OF SFC/ML BASED
INSTABILITY WE WERE UNABLE TO GENERATE OVER THE AREA TODAY WITH
PLENTY OF CLOUD COVER. THAT SAID...WE CAN NOT RULE OUT SOME
ISOLATED HAIL APPROACHING SEVERE LIMITS BASED ON STORMS EARLIER
NEAR CHICAGO. LOCAL WIND GUSTS CAN NOT BE RULED OUT EITHER WITH
THE STRONG WIND FIELDS OVERHEAD.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 355 PM EDT SUN APR 15 2012
THERE ARE SEVERAL ISSUES TO DEAL WITH DURING THE SHORT TERM PART
OF THE FORECAST. FIRST IS HOW STRONG WILL THE LINE OF THUNDERSTORMS
WITH THE COLD FRONT BE? THEN THERE IS THE ISSUE OF DO WE NEED A
WIND ADVISORY MONDAY AS THE COLD AIR COMES IN BEHIND THE COLD
FRONT. FINALLY THERE IS THE ISSUE OF A FREEZE MONDAY NIGHT.
AS FOR THE CONVECTION WITH THE COLD FRONT... OUR STORY REMAINS
UNCHANGED. THEN NAM 12Z... RUC 18Z ...GFS 12Z... AND ECMWF 12Z ALL
SHOW A 60 TO 70 KNOT LOW LEVEL JET COMING ON SHORE AROUND 2 AM THEN
REACHING EASTERN LOWER MICHIGAN BY 8 AM MONDAY. SINCE AT 18Z AND
19Z THE THUNDERSTORMS AREA WHERE THEY ARE SUPPOSE TO BE ON THE LEFT
SIDE OF THE LOW LEVEL JET... THAT MEANS THE MAIN LINE OF STORMS
WILL CROSS OUR CWA AROUND TO AFTER MIDNIGHT. WHAT HELPS TO KEEP
THE STORMS FROM GOING SEVERE OVER OUR CWA THROUGH IS THE JET CORE
AT 300 MB IS CURRENTLY SOUTHWEST OF MICHIGAN AND WILL NOT BE WEST
OF MICHIGAN UNTIL 2 AM. THAT MEANS THIS AREA WILL BE IN THE RIGHT
EXIT REGION OF THE UPPER JET CORE. THAT IS NOT CONDUCIVE TO SEVERE
STORMS. THE MOST UNSTABLE CAPE IN THE 950 TO 850 LAYER IS OVER
1500 J/KG OVER WI THIS EVENING BUT LESS THEN 400 J/KG OVER MI WHEN
THE LINE IS EXPECTED TO GET HERE. SO MY SPIN IS WE WILL SEE A
WEAKENING LINE OF STORMS COME INTO SOUTHWEST LOWER MICHIGAN AROUND
MIDNIGHT. THE LINE WILL WEAKEN AS IT CROSS THE CWA LATE TONIGHT.
ANY SEVERE WINDS WILL BE NEAR THE LAKE MICHIGAN SHORE AS THE
STORMS COME DOWN OFF THE MAINE LAYER.
THE DRY SLOT MOVES IN MID DAY MONDAY. SOUTHWEST MICHIGAN IS IN THE
DRY SLOT AND THERE IS 50 KNOTS IN THE MIXED LAYER AS THIS MOVES
ACROSS THE CWA. THIS WILL BRING OUR GUSTS CLOSE TO ADVISORY
CRITERIA WINDS BUT AT THIS POINT WE FEEL THIS IS OVER DONE BY THE
NAM SO WE WILL STAY JUST BELOW ADVISORY GUSTS.
WRAP AROUND MOISTURE MOVES IN DURING THE AFTERNOON SO SCATTERED
SHOWERS WILL MOVE INTO THE CWA BY EARLY TO MID AFTERNOON. THE AIR
BECOMES COLD ENOUGH FOR SNOW OVER THE NW CWA BY LATE AFTERNOON AND
OVER THE REST OF THE CWA BY MID EVENING. SO WE COULD SEE A FEW
SNOW FLAKES MONDAY EVENING. ENOUGH DRY AIR MOVES IN BEHIND THE
SYSTEM AFTER MIDNIGHT TO CLEAR THE SKIES AND THIS LEAD TO FROST
AND FREEZING TEMPERATURES. WE WILL LIKELY NEED A FREEZE WARNING
FOR TUESDAY MORNING.
$$
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 355 PM EDT SUN APR 15 2012
COOL AND DRY HIGH PRESSURE WILL BE SETTLING OVER THE REGION FOR
THE START OF LONG TERM. TUESDAY NIGHT COULD SEE MORE FROST WITH
TEMPS DIPPING TO AROUND 30 OVER THE INTERIOR NORTH...AND UPPER 30S
OVER THE SOUTHERN NEAR SHORE.
HAVE PUSHED THE POPS BACK A BIT ON WED. LOOKS LIKE ANY PCPN WILL
HOLD OFF UNTIL WED AFTERNOON...AND MAYBE NOT UNTIL AFTER NIGHTFALL
IN THE EAST. ANOTHER RATHER WOUND-UP NORTHERN STREAM SYSTEM WILL BE
MOVING ALONG THE U.S./CANADIAN BORDER...DRAGGING A COLD FRONT
THROUGH LOWER MICHIGAN WED NIGHT. AFTER A BRIEF BREAK FROM THE PCPN
ON THURSDAY...THE FRONT WILL STALL TO OUR SOUTH WITH A WAVE OF LOW
PRESSURE TRACKING ALONG IT. NOT GOOD AGREEMENT IN THE MODELS WITH
THE POSITION OF THIS LOW WITH THE EURO MUCH FURTHER NORTH THAN THE
GFS. THIS IS CAUSED BY THE FURTHER NORTHERLY POSITION OF THE
BAROCLINIC ZONE ON THE EURO. LOOKS LIKE THE HIGH OVER SOUTHERN
CANADA WILL BE THE DECIDER...IF THIS PROVES TO BE STRONGER THE PCPN
WILL STAY SOUTH. WILL SEE HOW THIS PANS OUT...FOR NOW HAVE
CONTINUED THE CHC POPS...HIGHEST SOUTH FOR THURSDAY NIGHT AND FRIDAY.
EVEN THE EURO EXITS ANY LINGER PCPN BY FRIDAY NIGHT. NEXT WEEKEND
LOOKS DRY WITH HIGH PRESSURE SLOWLY BUILDING IN. HOWEVER...IT DOES
APPEAR TO REMAIN COOL WITH MAX TEMPS MAINLY 50 TO 55...AND MAYBE
HOLDING IN THE 40S ALONG THE LAKESHORE.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 747 PM EDT SUN APR 15 2012
SHOWERS AND THUNDERSTORMS WILL BRING AREAS OF MVFR TONIGHT WITH
SOME ISOLATED IFR POSSIBLE. OTHERWISE...THE WIND WILL BE THE BIG
AVIATION IMPACT WITH GUSTS OVER 30 KNOTS BEGINNING TONIGHT AND
CONTINUING THROUGH MONDAY.
&&
.MARINE...
ISSUED AT 355 PM EDT SUN APR 15 2012
DUE TO THE 40 TO 50 KNOTS IN THE MIXED LAYER MONDAY... I CONTINUED
WITH THE GALE WARNING FOR MONDAY INTO MONDAY EVENING. I ALSO
CONTINUED TO MENTION AREAS OF FOG IN THE NEAR SHORE DUE THE HIGH
DEW POINTS OVER THE COLD LAKE. THE SOUTH BUOY HAD 42 DEGREES AT
18Z.
&&
.HYDROLOGY...
ISSUED AT 355 PM EDT SUN APR 15 2012
THERE WAS BETWEEN A HALF INCH AND TWO INCHES OF RAIN EARLY THIS
MORNING OVER MOST OF THE CWA. THE USGS PAGE SHOWS RIVER AND STREAM
LEVELS NEAR AND SOUTH OF I-96 ROSE SHARPLY THIS MORNING BUT REMAIN
WILL BELOW NORMAL NORTH OF I-96. THE RAINFALL THIS EVENING SHOULD
BE LESS THAN A HALF INCH AND HAVE LITTLE IMPACT ON STREAM LEVELS.
ONLY SYCAMORE CREEK NEAR HOLT IS FORECAST TO RISE TO NEAR ADVISORY
STAGE. WE WILL CONTINUE TO MONITOR THIS. THE BOTTOM LINE IS WE DO
NOT AT THIS POINT SEE MAJOR FLOODING ISSUES AT THIS TIME.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 11 AM EDT MONDAY FOR LMZ844>849.
GALE WARNING FROM 11 AM TO 10 PM EDT MONDAY FOR LMZ844>849.
&&
$$
UPDATE...NJJ
SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...JK
AVIATION...OSTUNO
HYDROLOGY...WDM
MARINE...WDM
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
900 PM EDT SUN APR 15 2012
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 446 PM EDT SUN APR 15 2012
SHORT TERM FCST HAS BEEN A CHALLENGE TODAY WITH IMPORTANT DETAILS TO
CAPTURE IN THE GRIDS WITH NEARLY ALL FCST ELEMENTS... INCLUDING
SIGNIFICANT NON-DIURNAL TEMPS TRENDS...GALES ON THE LAKE/POSSIBLE
ADVY WINDS INLAND...POSSIBLE SVR TSRA TONIGHT...AND MIX PCPN ISSUES
MON.
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A VIGOROUS SHORTWAVE
LIFTING NE THRU THE WRN PLAINS. SFC LOW IS OVER NE NEBRASKA WITH SFC
WARM FRONT EXTENDING NE TO NEAR KMSP THAN E TO JUST N OF KGRB. FRONT
HAS MADE LITTLE PROGRESS OVER THE LAST FEW HRS...AND SO FAR...THERE
HASN`T BEEN MUCH SHRA ACTIVITY N OF THE FRONT. STRONGER LOW-MIDLEVEL
FRONTOGENESIS IS SUPPORTING BEST SHRA DEVELOPMENT TO THE W IN NE
MN/WRN LAKE SUPERIOR. HOWEVER...WITH MODELS INDICATING MOISTURE
TRANSPORT BECOMING FOCUSED TOWARD UPPER MI OVER THE NEXT FEW HRS...
SHRA SHOULD EXPAND OVER THE FCST AREA. WITH ELEVATED CAPE ALSO
INCREASING...ISOLD/SCT TSRA SHOULD ALSO DEVELOP. SVR THREAT IS
UNCERTAIN TONIGHT DUE TO UNCERTAINTY IN PROGRESS OF WARM FRONT. IF
FRONT LINGERS TO S THIS EVENING AND ELEVATED STORMS DO DEVELOP...
EFFECTIVE SHEAR WILL SUPPORT ORGANIZED UPDRAFTS AND A HAIL
POTENTIAL...ESPECIALLY OVER THE SCNTRL. IF WARM FRONT LIFTS N THRU
CNTRL/ERN UPPER MI...THERE MAY NOT BE MUCH ACTIVITY UNTIL COLD FRONT
ARRIVES LATE TONIGHT WHEN INSTABILITY WILL BE DIMINISHING. AT THIS
POINT...ELEVATED SVR STORMS APPEAR THE MORE LIKELY SCENARIO IF
STORMS CAN ORGANIZE N OF SLOW MOVING WARM FRONT. TEMPS TONIGHT WILL
ALSO BE HIGHLY DEPENDENT ON WARM FRONT LOCATION. TEMPS MAY RISE
ACROSS THE CNTRL/E WHILE A CHILLY E WIND KEEPS READINGS OVER THE
KEWEENAW IN THE LWR 40S. FOG MAY BE DENSE AT TIMES WHERE FLOW IS
UPSLOPE OFF LAKE SUPERIOR AND LAKE MICHIGAN.
SFC LOW WILL TRACK ACROSS CNTRL UPPER MI/SE LAKE SUPERIOR LATE
TONIGHT/MON MORNING. SHARP/STRONG CAA MON WILL BRING A QUICK DROP IN
TEMPS FROM NW TO SE AFTER COLD FROPA. FCST SOUNDINGS SUGGEST AT
LEAST SOME POTENTIAL FOR A BRIEF PERIOD OF SLEET BTWN THE TRANSITION
FROM RAIN TO SNOW. LOW-LEVEL TEMPS ALSO APPEAR TO FALL ENOUGH FOR
SOME LAKE ENHANCEMENT IN THE DEFORMATION PCPN AREA SWINGING ACROSS
UPPER MI MON. RIGHT NOW...EXPECT 1 TO 2 INCHES OF SNOW MON OVER THE
W AND NCNTRL. HIGH TERRAIN OF THE FAR W MAY SEE UP TO 3 INCHES.
COULD BE A SNOW ADVY EVENT IF DEFORMATION PCPN SHIELD BECOMES WELL
ORGANIZED TO THE W TONIGHT. AS FOR WINDS...SHARP CAA WILL ENHANCE
LOW-LEVEL MIXING...AND WITH 40-45KT AVBL IN THE MIXED LAYER...ADVY
LEVEL WINDS ARE A GOOD BET NEAR LAKE SUPERIOR MON...ESPECIALLY
KEWEENAW COUNTY BEGINNING IN THE MORNING AND FROM KMQT EASTWARD IN
THE AFTN. ISALLOBARIC COMPONENT TO THE WIND ROUGHLY 90 DEGREES TO
THE GRADIENT WIND SHOULD KEEP THIS FROM BEING A HIGHER END WIND
EVENT. TEMPS WILL FALL FROM NW TO SE THRU THE DAY...THOUGH THERE
WILL BE SOME WARMING OVER THE E MON MORNING PRIOR TO COLD FROPA.
TEMPS IN THE AFTN WILL PROBABLY BE AT OR BELOW FREEZING OVER THE W
AND NCNTRL.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 446 PM EDT SUN APR 15 2012
NO SIGNIFICANT CHANGES TO UPPER PATTERN DEPICTION SHOWN BY MEDIUM
RANGE MODELS YDY WITH NEGATIVE ANAMOLIES STATIONED OVER NORTHEAST
PACIFIC OCEAN/GULF OF ALASKA AND OVR HUDSON BAY INTO NUNAVUT CANADA.
ZONAL FLOW DOMINATES CONUS MUCH OF THE WEEK AND REALLY INTO NEXT
WEEKEND AS WELL. ATTM ONLY ONE SYSTEM WILL IMPACT THE AREA IN THE
LONGER TERM...BUT THAT MAY CHANGE DEPENDING ON TRACK OF LATE WEEK
SYSTEM.
BLAST OF WINTRY WEATHER GRADUALLY DIMINISHES ON MONDAY NIGHT. PLENTY
OF 925-850MB MOISTURE...CYCLONIC SFC-H85 FLOW...AND 900 TEMPS AROUND
-10C SO PREFER TO LET SNOW SHOWERS LINGER ALONG LK SUPERIOR INTO THE
OVERNIGHT HOURS FOR AREAS FAVORED BY NW WINDS. ADDITIONAL SNOW
ACCUMS MONDAY NIGHT WILL STILL BE MINIMAL. MAIN ISSUE WILL BE GUSTY
NORTH-NORTHWEST WINDS UP TO 45 MPH ALONG LK SUPERIOR ALONG WITH THE
SNOW SHOWERS. ARRIVAL OF LOW-LEVEL RIDGE DIMINISHES SNOW SHOWERS
TOWARD MORNING OVER EASTERN CWA. SFC RIDGE AND EDGE OF THERMAL TROUGH
RESULTS IN LIGHT WINDS/COOL CONDITIONS ON TUESDAY. COOLEST READINGS
AROUND 40 DEGREES ALONG LK SUPERIOR WITH NE WINDS.
SHORTWAVE ON SOUTHERN EDGE OF TROUGH OVR GULF OF ALASKA FCST TO
SLIDE ACROSS ROCKIES INTO NORTHERN PLAINS BY TUESDAY NIGHT AND PUSH
ACROSS UPPER GREAT LAKES ON WEDNESDAY. SW WINDS AHEAD OF SFC-H85
TROUGH HELP TO BRING MUCH WARMER AIR INTO UPR LAKES IN WAKE OF EARLY
WEEK CHILL AND INCREASING MOISTURE AS WELL. JET STREAKS SLIDING
ACROSS THE NORTHERN PLAINS AND OVR ONTARIO SHOULD HELP SYSTEM STAY
FAIRLY ORGANIZED AS IT CROSSES CWA ON WEDNESDAY. MSLP FCSTS DEPICT
THIS AS WELL WITH PRESSURES STEADY OR EVEN SLOWLY FALLING FM TUESDAY
NIGHT INTO WEDNESDAY ACROSS UPPER LAKES. GIVEN OVERALL DRY PATTERN
WE ARE IN CANNOT GET TOO EXCITED ABOUT SIGNIFICANT PRECIPITATION
WITH THE SYSTEM...BUT TOTAL LIQUID COULD CHECK IN AROUND 0.25 INCH
IN SOME AREAS. PTYPE MAY BE ISSUE INITIALLY LATE TUESDAY NIGHT OVER
THE WEST AS SHALLOW COLD AIR HANGS TOUGH IN WAKE OF COLD PUSH EARLY
IN THE WEEK. LATEST MODEL RUNS INDICATE POTENTIAL FOR FROZEN PRECIP
IS NOT AS HIGH AS BEFORE AS SOUTH WINDS ADVECT WELL ABOVE FREEZING
DWPNTS INTO UPR MI BY DAYBREAK WEDNESDAY. OVERALL...MAY BE SOME SNOW
OR PERHAPS FREEZING RAIN...BUT AS IT STANDS NOW IT WOULD BE PRETTY
SHORT LIVED. SOME POTENTIAL SOME SNOW AS SYSTEM EXITS ON WEDNESDAY
NIGHT. 850MB/925MB TEMPS AS LOW AS -10C/-6C WOULD EVEN OPEN DOOR TO
BRIEF LAKE ENHANCED SNOW OVR HIGHER TERRAIN OF WEST GIVEN ENOUGH
MOISTURE REMAINS AS COLDER AIR WORKS INTO UPR LAKES REGION.
IN THE EXTENDED...FRIDAY SYSTEM THAT ECMWF HAS BEEN SHOWING OFF AND
ON THE LAST FEW DAYS WAS OFF ON THE 00Z RUN BUT IS KIND OF BACK ON
AGAIN WITH THE 12Z RUN...THOUGH BULK OF HEAVIER QPF REMAINS SOUTH OF
UPR MI. GFS IS MUCH FARTHER SOUTH. SOUTHERN TRACK DOES MAKE SOME
SENSE AS PRIMARY FRONTAL BOUNDARY IS FCST TO SETTLE INTO THE
NORTHERN PORTIONS OF THE OHIO VALLEY IN WAKE OF THE WEDNESDAY SYSTEM
AND SINCE BETTER CHANCE OF CYCLOGENESIS WOULD BE ALONG THE BETTER
SFC TEMPERATURE GRADIENT. SYSTEM IS STILL NEAR THE ALLUTIANS IN THE
PACIFIC SO THERE LIKELY WILL BE SOME JUMPING AROUND ON THE POSITION
OF THE LOW YET THIS WEEK. FOR NOW THOUGH...POPS WILL STAY ON THE LOW
SIDE FOR THIS SYSTEM WITH THE HIGHER POPS OVER THE SOUTHERN CWA
THURSDAY NIGHT AND FRIDAY. ECMWF IDEA FM 12Z/14 APRIL AND 12Z THIS
MORNING WOULD INDICATE SIGNIFICANT SNOW OVR PORTIONS OF UPR LAKES
INCLUDING UPR MI.
BEYOND FRIDAY APPEARS DRY WEATHER IS IN STORE FOR NEXT WEEKEND. WILL
NOT BE ESPECIALLY WARM THOUGH AS LARGER SCALE TROUGH RESIDES OVR
MUCH OF EASTERN CANADA AND EASTERN CONUS. MODELS SHOW ANOTHER WAVE
DIVING IN FM THE PACIFIC TROUGH BUT WITH EXPECTED AMPLITUDE OF
TROUGH THIS SYSTEM WILL PROBABLY STAY TO THE SOUTH OF UPR LAKES AS
THE LATE WEEK ONE DOES. SFC-H85 RIDGE WILL BE OVERHEAD LEADING TO
LIGHT WINDS/LK BREEZES. BEST CHANCE FOR DAYTIME TEMPS AT LEAST NEAR
NORMAL WILL BE WELL INLAND FM THE LAKES TOWARD WISCONSIN BORDER.
COULD ALSO BE CHILLY NIGHTS AS WELL...WITH TEMPS POSSIBLY IN THE
TEENS AND 20S. RELATIVE HUMIDITIES LIKELY WILL BE ON THE LOW SIDE
FOR THE WEEKEND AS WELL.
APPEARS PATTERN BEGINS TO CHANGE DAYS 8-10 OR STARTING ON 24 APRIL
AS STRONG RIDGE BUILDS FM CNTRL CONUS INTO WESTERN GREAT LAKES.
GIVEN LACK OF RAINFALL THIS MONTH AND SINCE WE ARE STILL NOT
COMPLETELY GREENED UP OVR UPR MI...THE WARMER AND DRY WEATHER WILL
PROBABLY LEAD TO INCREASING FIRE WEATHER ISSUES. PLENTY OF TIME TO
DIAGNOSE THIS THOUGH.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 857 PM EDT SUN APR 15 2012
FORECAST OVER THE NEXT 24 HOURS IS FAIRLY COMPLEX WITH A LOW
PRESSURE SYSTEM AND WARM FRONT SHIFTING NORTHEASTWARD THROUGH MUCH
OF THE UPPER PENINSULA. VISIBILITY AND CEILING HEIGHT WILL BE THE
MAIN CONCERN FOR THE FIRST 10 TO 12 HOURS WITH WINDS BECOMING AN
ISSUE TOWARD THE LAST HALF OF THE TAF PERIOD. RADAR IS CURRENTLY
INDICATING SHOWERS AND THUNDERSTORMS APPROACHING IRONWOOD JUST
BEFORE 00Z SO HAVE INCLUDED VCTS IN THE IWD TAF. CONFIDENCE IS LOW
ENOUGH AT THIS POINT THAT TS HAVE NOT BEEN MENTIONED IN THE CMX OR
SAW TAF. VISIBILITY SHOULD REMAIN LOW AT EACH TAF SITE...POTENTIALLY
APPROACHING AIRPORT MINIMUMS. HAVE INCLUDED A TEMPO FOR LOWER
VISIBILITY AT SAW AS EAST AND SOUTHEAST WINDS WOULD BE AN UPSLOPE
WIND ALSO HELPING TO REDUCE VISIBILITY AND CEILINGS. AS THE WINDS
SHIFT AROUND TO THE SOUTH EXPECT A SLIGHT INCREASE IN CEILING
HEIGHTS AT SAW AND AN INCREASE IN VISIBILITY BUT LIKELY REMAINING AT
OR BELOW IFR THROUGH 14Z. AS THE LOW SHIFTS TO THE EAST OF THE AREA
NORTHERLY FLOW ON THE BACK SIDE WILL ALLOW FOR A CHANGE OVER TO ALL
SNOW STARTING FIRST AT IWD AND CMX. WINDS WILL BECOME STRONG AND
GUSTY FROM THE NORTH AS PRESSURE GRADIENT REMAINS TIGHT ON THE BACK
SIDE OF THE LOW. WINDS COULD GUST AS HIGH AS 30 TO 35 KTS BY THE
LAST HALF OF THE TAF PERIOD. HAVE ALSO KEPT LLWS THROUGH LATE THIS
EVENING AT SAW AS LOW-LEVEL WINDS STRENGTHEN JUST ABOVE A SHALLOW
STABLE LAYER AHEAD OF THE FRONT.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 446 PM EDT SUN APR 15 2012
SFC LOW TRACKING FROM NE NEBRASKA TO UPPER MI/SE LAKE SUPERIOR
TONIGHT/MON MORNING WILL BRING A NE TO N GALE EVENT TO LAKE SUPERIOR
TONIGHT AND MON. GALES HAVE BEEN A LITTLE SLOW TO DEVELOP OVER THE
FAR W THIS AFTN...BUT WINDS SHOULD QUICKLY RAMP UP OVER THE NEXT FEW
HRS AS PRES FALLS INCREASE IN MAGNITUDE TO THE SW OF THE LAKE AHEAD
OF THE APPROACHING SFC LOW. AS THE LOW SHIFTS ACROSS UPPER MI/SE
LAKE SUPERIOR AND THEN E MON...NE WINDS WILL BACK N WITH GALES
QUICKLY EXPANDING E ACROSS THE LAKE. SHARP CAA/STRONG LOW-LEVEL
INSTABILITY WILL SUPPORT FREQUENT HIGH END GALE GUSTS. WINDS WILL
DIMINISH TO UNDER 20KT FROM W TO E MON NIGHT/EARLY TUE AS HIGH PRES
RIDGE BUILDS SE TO THE UPPER LAKES. LIGHTER WINDS WILL PERSIST THRU
TUE AFTN. NEXT LOW PRES SYSTEM MOVING THRU THE UPPER LAKES WED WILL
BRING ANOTHER PERIOD OF 15-25KT WINDS WED/THU...WITH THE STRONGER
WINDS AFFECTING MAINLY THE E HALF OF THE LAKE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 5 PM MONDAY TO 2 AM EDT TUESDAY FOR LSZ251-267.
GALE WARNING FROM 11 AM MONDAY TO 2 AM EDT TUESDAY FOR LSZ266.
GALE WARNING UNTIL 2 PM EDT /1 PM CDT/ MONDAY FOR LSZ162.
GALE WARNING UNTIL 8 PM EDT MONDAY FOR LSZ242>244-263-264.
GALE WARNING FROM 11 AM TO 8 PM EDT MONDAY FOR LSZ265.
GALE WARNING FROM 2 PM MONDAY TO 2 AM EDT TUESDAY FOR LSZ249-250.
GALE WARNING FROM 2 PM TO 8 PM EDT MONDAY FOR LSZ248.
GALE WARNING FROM 5 AM TO 8 PM EDT MONDAY FOR LSZ245.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...KEC
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
748 PM EDT SUN APR 15 2012
.SYNOPSIS...
ISSUED AT 355 PM EDT SUN APR 15 2012
A STRONG COLD FRONT WILL CROSS SOUTHWEST LOWER MICHIGAN OVERNIGHT.
IT WILL ACCOMPANIED BY A LINE OF THUNDERSTORMS WITH GUSTY WINDS.
TEMPERATURES WILL FALL DURING MONDAY WITH GUSTY WINDS. EARLY MORNING
SHOWERS AND THUNDERSTORMS WILL GIVE WAY TO SCATTERED AFTERNOON
SHOWERS. THOSE COULD BE MIXED WITH WET SNOW OVER NORTHWEST
SECTIONS BY LATE AFTERNOON. SPRINKLES AND FLURRIES WILL END MONDAY
NIGHT AND THAT WILL LEAD TO CLEARING SKIES WITH FROST AND FREEZING
TEMPERATURES. A QUICK MOVING SYSTEM WILL BRING MORE SHOWERS TO THE
AREA WEDNESDAY.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 355 PM EDT SUN APR 15 2012
THERE ARE SEVERAL ISSUES TO DEAL WITH DURING THE SHORT TERM PART
OF THE FORECAST. FIRST IS HOW STRONG WILL THE LINE OF THUNDERSTORMS
WITH THE COLD FRONT BE? THEN THERE IS THE ISSUE OF DO WE NEED A
WIND ADVISORY MONDAY AS THE COLD AIR COMES IN BEHIND THE COLD
FRONT. FINALLY THERE IS THE ISSUE OF A FREEZE MONDAY NIGHT.
AS FOR THE CONVECTION WITH THE COLD FRONT... OUR STORY REMAINS
UNCHANGED. THEN NAM 12Z... RUC 18Z ...GFS 12Z... AND ECMWF 12Z ALL
SHOW A 60 TO 70 KNOT LOW LEVEL JET COMING ON SHORE AROUND 2 AM THEN
REACHING EASTERN LOWER MICHIGAN BY 8 AM MONDAY. SINCE AT 18Z AND
19Z THE THUNDERSTORMS AREA WHERE THEY ARE SUPPOSE TO BE ON THE LEFT
SIDE OF THE LOW LEVEL JET... THAT MEANS THE MAIN LINE OF STORMS
WILL CROSS OUR CWA AROUND TO AFTER MIDNIGHT. WHAT HELPS TO KEEP
THE STORMS FROM GOING SEVERE OVER OUR CWA THROUGH IS THE JET CORE
AT 300 MB IS CURRENTLY SOUTHWEST OF MICHIGAN AND WILL NOT BE WEST
OF MICHIGAN UNTIL 2 AM. THAT MEANS THIS AREA WILL BE IN THE RIGHT
EXIT REGION OF THE UPPER JET CORE. THAT IS NOT CONDUCIVE TO SEVERE
STORMS. THE MOST UNSTABLE CAPE IN THE 950 TO 850 LAYER IS OVER
1500 J/KG OVER WI THIS EVENING BUT LESS THEN 400 J/KG OVER MI WHEN
THE LINE IS EXPECTED TO GET HERE. SO MY SPIN IS WE WILL SEE A
WEAKENING LINE OF STORMS COME INTO SOUTHWEST LOWER MICHIGAN AROUND
MIDNIGHT. THE LINE WILL WEAKEN AS IT CROSS THE CWA LATE TONIGHT.
ANY SEVERE WINDS WILL BE NEAR THE LAKE MICHIGAN SHORE AS THE
STORMS COME DOWN OFF THE MAINE LAYER.
THE DRY SLOT MOVES IN MID DAY MONDAY. SOUTHWEST MICHIGAN IS IN THE
DRY SLOT AND THERE IS 50 KNOTS IN THE MIXED LAYER AS THIS MOVES
ACROSS THE CWA. THIS WILL BRING OUR GUSTS CLOSE TO ADVISORY
CRITERIA WINDS BUT AT THIS POINT WE FEEL THIS IS OVER DONE BY THE
NAM SO WE WILL STAY JUST BELOW ADVISORY GUSTS.
WRAP AROUND MOISTURE MOVES IN DURING THE AFTERNOON SO SCATTERED
SHOWERS WILL MOVE INTO THE CWA BY EARLY TO MID AFTERNOON. THE AIR
BECOMES COLD ENOUGH FOR SNOW OVER THE NW CWA BY LATE AFTERNOON AND
OVER THE REST OF THE CWA BY MID EVENING. SO WE COULD SEE A FEW
SNOW FLAKES MONDAY EVENING. ENOUGH DRY AIR MOVES IN BEHIND THE
SYSTEM AFTER MIDNIGHT TO CLEAR THE SKIES AND THIS LEAD TO FROST
AND FREEZING TEMPERATURES. WE WILL LIKELY NEED A FREEZE WARNING
FOR TUESDAY MORNING.
$$
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 355 PM EDT SUN APR 15 2012
COOL AND DRY HIGH PRESSURE WILL BE SETTLING OVER THE REGION FOR
THE START OF LONG TERM. TUESDAY NIGHT COULD SEE MORE FROST WITH
TEMPS DIPPING TO AROUND 30 OVER THE INTERIOR NORTH...AND UPPER 30S
OVER THE SOUTHERN NEAR SHORE.
HAVE PUSHED THE POPS BACK A BIT ON WED. LOOKS LIKE ANY PCPN WILL
HOLD OFF UNTIL WED AFTERNOON...AND MAYBE NOT UNTIL AFTER NIGHTFALL
IN THE EAST. ANOTHER RATHER WOUND-UP NORTHERN STREAM SYSTEM WILL BE
MOVING ALONG THE U.S./CANADIAN BORDER...DRAGGING A COLD FRONT
THROUGH LOWER MICHIGAN WED NIGHT. AFTER A BRIEF BREAK FROM THE PCPN
ON THURSDAY...THE FRONT WILL STALL TO OUR SOUTH WITH A WAVE OF LOW
PRESSURE TRACKING ALONG IT. NOT GOOD AGREEMENT IN THE MODELS WITH
THE POSITION OF THIS LOW WITH THE EURO MUCH FURTHER NORTH THAN THE
GFS. THIS IS CAUSED BY THE FURTHER NORTHERLY POSITION OF THE
BAROCLINIC ZONE ON THE EURO. LOOKS LIKE THE HIGH OVER SOUTHERN
CANADA WILL BE THE DECIDER...IF THIS PROVES TO BE STRONGER THE PCPN
WILL STAY SOUTH. WILL SEE HOW THIS PANS OUT...FOR NOW HAVE
CONTINUED THE CHC POPS...HIGHEST SOUTH FOR THURSDAY NIGHT AND FRIDAY.
EVEN THE EURO EXITS ANY LINGER PCPN BY FRIDAY NIGHT. NEXT WEEKEND
LOOKS DRY WITH HIGH PRESSURE SLOWLY BUILDING IN. HOWEVER...IT DOES
APPEAR TO REMAIN COOL WITH MAX TEMPS MAINLY 50 TO 55...AND MAYBE
HOLDING IN THE 40S ALONG THE LAKESHORE.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 747 PM EDT SUN APR 15 2012
SHOWERS AND THUNDERSTORMS WILL BRING AREAS OF MVFR TONIGHT WITH
SOME ISOLATED IFR POSSIBLE. OTHERWISE...THE WIND WILL BE THE BIG
AVIATION IMPACT WITH GUSTS OVER 30 KNOTS BEGINNING TONIGHT AND
CONTINUING THROUGH MONDAY.
&&
.MARINE...
ISSUED AT 355 PM EDT SUN APR 15 2012
DUE TO THE 40 TO 50 KNOTS IN THE MIXED LAYER MONDAY... I CONTINUED
WITH THE GALE WARNING FOR MONDAY INTO MONDAY EVENING. I ALSO
CONTINUED TO MENTION AREAS OF FOG IN THE NEAR SHORE DUE THE HIGH
DEW POINTS OVER THE COLD LAKE. THE SOUTH BUOY HAD 42 DEGREES AT
18Z.
&&
.HYDROLOGY...
ISSUED AT 355 PM EDT SUN APR 15 2012
THERE WAS BETWEEN A HALF INCH AND TWO INCHES OF RAIN EARLY THIS
MORNING OVER MOST OF THE CWA. THE USGS PAGE SHOWS RIVER AND STREAM
LEVELS NEAR AND SOUTH OF I-96 ROSE SHARPLY THIS MORNING BUT REMAIN
WILL BELOW NORMAL NORTH OF I-96. THE RAINFALL THIS EVENING SHOULD
BE LESS THAN A HALF INCH AND HAVE LITTLE IMPACT ON STREAM LEVELS.
ONLY SYCAMORE CREEK NEAR HOLT IS FORECAST TO RISE TO NEAR ADVISORY
STAGE. WE WILL CONTINUE TO MONITOR THIS. THE BOTTOM LINE IS WE DO
NOT AT THIS POINT SEE MAJOR FLOODING ISSUES AT THIS TIME.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 11 AM EDT MONDAY FOR LMZ844>849.
GALE WARNING FROM 11 AM TO 10 PM EDT MONDAY FOR LMZ844>849.
&&
$$
SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...JK
AVIATION...OSTUNO
HYDROLOGY...WDM
MARINE...WDM
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
413 PM EDT SAT APR 14 2012
.SYNOPSIS...
ISSUED AT 412 PM EDT SAT APR 14 2012
A WARM FRONT WILL BRING A PERIOD OF THUNDERSTORMS WITH LOCALLY
HEAVY RAINFALL LATE TONIGHT INTO MID MORNING SUNDAY. THE COLD
FRONT MONDAY NIGHT WILL BRING AN PERIOD OF THUNDERSTORMS WITH
GUSTY WINDS WITH IT. NO MONDAY IT WILL BECOME VERY WINDY WITH
FALLING TEMPERATURES DURING THE DAY AS WELL AS SCATTERED SHOWERS.
FROST AND FREEZING TEMPERATURES ARE EXPECTED BY TUESDAY MORNING.
&&
.SHORT TERM...(THIS EVENING THROUGH SUNDAY NIGHT)
ISSUED AT 412 PM EDT SAT APR 14 2012
LITTLE CHANGE IN THINKING FROM MY LATE MORNING DISCUSSION. A
PERIOD OF THUNDERSTORMS (NOT SEVERE) WITH THE WARM FRONT
TONIGHT...DRY MIDDAY SUNDAY UNTIL MID EVENING...THEN THE FRONTAL
RAIN BAND WITH GUSTY WINDS LATE EVENING SUNDAY INTO THE EARLY
MORNING HOURS OF MONDAY.
TONIGHT THE LOW LEVEL JET BIFURCATES WITH PART OF IT GOING INTO OHIO
AND THE REST OF IT HEADED TOWARD MN/WI. THAT ALSO IS NOT CONDUCIVE
FOR CONVECTION HERE. IT IS NOT UNTIL MID MORNING SUNDAY THE
SOUTHERN BRANCH OF THE BIFURCATED LOW LEVEL JET EVEN SHOWS A SIGN OF
GETTING INTO THE I-94 REGION AND BY THEN IT IS WEAKENING. THE
PRIMARY CORE STAYS OVER WI/MI/IA THROUGH THE DAY AND SLOWLY
DEVELOPS NORTHWARD NOT EASTWARD. SO I EXPECT A BAND OF
THUNDERSTORMS TO HEAD NORTH THROUGH LOWER MICHIGAN MID MORNING BUT
WILL LIKELY NOT BE SEVERE (NOT SURFACE BASED). THE HRRR RUC FROM
THE 16Z MODEL RUN SHOWS THIS NICELY. SO MOST OF THE RAIN FROM THE
WARM FRONTAL RAIN BAND WILL BE BETWEEN MIDNIGHT AND 10 AM MONDAY.
THE MODELS AND SOUNDING SHOW NO SURFACE BASED CAPE AND ONLY 500 TO
1000 J/KG OF MOST UNSTABLE CAPE (FROM 800 MB LAYER). THUS I DO NOT
SEE MUCH OF SEVERE THREAT TONIGHT WITH THESE STORMS. JUST LOCALLY
HEAVY RAINFALL.
ON SUNDAY THE WARM FRONT LIFTS NORTH OF THE CWA AND SO WILL THE
ASSOCIATED CONVECTION. THERE IS SURFACE BASED INSTABILITY SUNDAY BUT
NO FOCUS SO I DO NOT BELIEVE WE WILL BE SEEING MUCH IF ANY
CONVECTION IN THE GRR CWA DURING THE AFTERNOON. IF THE SUN REALLY
CAME OUT TEMPERATURES COULD REACH 80 SOUTH OF INTERSTATE 96.
SUNDAY NIGHT WILL BE OUR CONVECTIVE "SHOW" IF ONE COULD CALL IT
THAT. IT TAKES UNTIL 2 AM FOR THE LOW LEVEL JET CORE TO GET TO
I-31. WHILE FORECAST SHOWS 1500-2000 J/KG OF SURFACE BASED CAPE
OVER WI SUN AFTERNOON BY THE TIME THIS REACHES LOWER MICHIGAN
AFTER MIDNIGHT IT IS LESS THE 500 J/KG. ON THE OTHER HAND WE DO
STILL HAVE SURFACE BASED CAPE SO AND A 60 TO 70 KNOT LOW LEVEL
JET. GIVEN THE LOW CAPE VALUE LARGE HAIL SEEMS OUT OF THE
QUESTION. MOSTLY GUSTY WINDS BUT WITH WEAK CAPE ONE HAS TO EVEN
WONDER ABOUT THAT. SO I AM NOT EXPECTING A MAJOR SEVERE OUTBREAK
IN OUR CWA FROM THIS EVENT. JUST ISOLATED SEVERE STORMS POSSIBLE
AFTER MIDNIGHT. SPC`S OUTLOOK FOR SUNDAY NIGHT INTO MONDAY AGREES
WITH THIS WITH A 15 PCT CHANCE OVER OUR NW CWA.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 412 PM EDT SAT APR 14 2012
TRENDED POPS LOWER FOR MONDAY AND ALSO TRENDED COOLER FOR MONDAY
NIGHT AND TUESDAY NIGHT. MODEL TRENDS ARE MORE PROGRESSIVE WITH
MOVING THE SURFACE LOW OUT OF THE AREA ON MONDAY. THIS SHOULD
RESULT IN QUICKER CLEARING MONDAY NIGHT...AND REMAINING MOSTLY CLEAR
TUESDAY NIGHT WITH HIGH PRESSURE OVER MI. FROST AND FREEZING TEMPS
WILL BE A CONCERN UNDER THIS SCENARIO...ESPECIALLY TUESDAY NIGHT AS
WINDS SHOULD BE LIGHTER.
NEXT CHANCE OF PCPN SHOULD HOLD OFF UNTIL WED AFTERNOON OR EVENING
AS A NORTHERN STREAM WAVE BRINGS A COLD FRONT LATE WED NIGHT OR
EARLY THU. THE FRONT THEN STALLS TO OUR SOUTH WITH OVER-RUNNING
PCPN LINGERING. IT APPEARS THE CWA WILL BE ON THE NORTHERN FRINGE
OF THIS PCPN...SO I HAVE HIGHER POPS IN THE SOUTHERN CWA...AND LOWER
POPS NORTH. THE EURO HOLDS ON TO PCPN RIGHT INTO SAT...BUT THE GFS
GOES DRY. HAVE FAVORED THE DRIER GFS AS THE PATTERN LOOKS MORE
PROGRESSIVE THAN WHAT THE EURO SUGGESTS. TEMPS WILL REMAIN COOLISH
WITH NE LOW LEVEL FLOW.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 118 PM EDT SAT APR 14 2012
MVFR CIGS PREVAIL ACROSS ALL OF THE TAF SITES AT 17Z. HOWEVER THE
LOW CLOUD EDGE IS ERODING FROM EAST TO WEST TOWARD THE LAKE
MICHIGAN SHORE. THE NAM SUGGESTS THE LOW CLOUDS WILL HOLD ON
LONGEST NEAR LAKE MICHIGAN (MKG) SO I BROKE OUT THE LOW CLOUDS AT
LAN AND BTL FIRST AND AZO AND GRR NEXT THEN MKG LAST.
TONIGHT THE BAND OF THUNDERSTORMS WITH THE SURGE OF WARM MOIST AIR
WILL MOVE FROM SOUTH TO NORTH ACROSS THE CWA SO I TIMED THE STORM
THAT WAY THROUGH THE CWA. I EXPECT IFR CIGS/VSBY WITH THIS. ONCE
THE WARM FRONT IS NORTH OF HERE CIGS/VSBY WILL BECOME VFR. SKIES
MAY ACTUALLY CLEAR BY EARLY AFTERNOON.
&&
.MARINE...
ISSUED AT 412 PM EDT SAT APR 14 2012
IF NOT FOR THE COLD LAKE AND WARM AIR WE WOULD HAVE A GALE WARNING
FOR SUNDAY INTO SUNDAY NIGHT HOWEVER WITH LAKE TEMPERATURES IN THE
LOWER 40S AND AIR TEMPERATURES COMING OFF ILLINOIS AND INDIANA IN
THE 70S SUNDAY THE WINDS WILL NOT MIX THROUGH THE MARINE LAYER.
THAT CHANGES MONDAY ONCE THE STRONG COLD FRONT COMES THROUGH. WE
MAY NEED GALES THEN...FOR NOW I AM GOING WITH A SMALL CRAFT
ADVISORY SUNDAY INTO MIDDAY MONDAY AND CALLING THAT GOOD.
&&
.HYDROLOGY...
ISSUED AT 412 PM EDT SAT APR 14 2012
LOCALLY HEAVY RAINFALL IS POSSIBLE TONIGHT WITH THE WARM FRONT
PRECIPITATION BAND MOVING NORTHWARD THROUGH SOUTHWEST LOWER
MICHIGAN. AT THIS POINT THROUGH WE DO NOT SEE A LARGE SCALE GENERAL
HEAVY RAINFALL. MOST LOCATIONS TONIGHT SHOULD GET AROUND A HALF
INCH. THE COLD FRONT RAIN BAND SHOULD NOT BE AS HEAVY...GENERALLY
AROUND A QUARTER INCH. THIS SHOULD NOT CAUSE TO MANY PROBLEMS FOR
OUR RIVERS BUT COULD LOCALLY CAUSE ISSUES ON SMALLER STREAMS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY FROM 8 AM SUNDAY TO 8 AM EDT MONDAY FOR
LMZ844>849.
&&
$$
SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...JK
AVIATION...WDM
HYDROLOGY...WDM
MARINE...WDM
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
123 PM EDT SAT APR 14 2012
.SYNOPSIS...
ISSUED AT 523 AM EDT SAT APR 14 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH OVER
THE WRN CONUS AND A RIDGE FROM THE GULF OF MEXICO THROUGH THE CNTRL
GREAT LAKES. A WELL-DEFINED SHRTWV OVER CNTRL WI SUPPORTED A SCT
BAND OF SHOWERS FROM WRN UPPER MI INTO SRN WI. A VERY POTENT
UPSTREAM SHRTWV THAT WILL IMPACT WX OVER THE WRN GREAT LAKES SUN
INTO SUN NIGHT WAS MOVING THROUGH WRN AZ. AT THE SFC...SRLY FLOW
PREVAILED THROUGH UPPER MI AHEAD OF A LOW OVER NW MN.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 523 AM EDT SAT APR 14 2012TODAY THROUGH SUNDAY EVENING
TODAY...ANY LINGERING SCT PCPN OVER THE NRN AND ERN FCST AREA WILL
MOVE OUT DURING THE MORNING AS THE DRY SLOT UNDERNEATH UPPER LEVEL
JET STREAK SHIFTS OVER THE AREA. EXPECT CLOUDS TO CLEAR OUT DURING
THE MORNING...PER UPSTREAM OBS OVER MN. WITH SUNSHINE AND DECENT
MIXING TEMPS SHOULD CLIMB TO AROUND 70 INLAND WITH DEWPOINTS FALLING
INTO THE MID 30S. WITH RH VALUES INTO THE 25 TO 30 PERCENT RANGE AND
GUSTY WSW WINDS...THERE WILL BE AN ELEVATED RISK OF WILDFIRES SAT
AFTERNOON...ESPECIALLY OVER THE W HALF WHERE TEMPS/WINDS WILL BE
HIGHEST.
TONIGHT INTO SUNDAY...AS THE SW CONUS SHORTWAVE LIFTS NE OUT OF THE
ROCKIES AND THROUGH THE PLAINS...SFC LOW PRES WILL DEVELOP OVER
NEBRASKA AND MOVE INTO THE UPPER MS VALLEY. THE MODELS HAVE TRENDED
STRONGER WITH THE SHORTWAVE AND MORE TO THE NW WITH THE SFC LOW AND
ASSOCIATED WARM FRONT INTO THE WRN GREAT LAKES WHICH SEEMS
REASONABLE GIVEN THE STRENGTH OF THE SHORTWAVE AND PROMINENT RIDGE
OVER THE SOUTHEAST INTO THE LAKES. A LARGE AREA OF PCPN IS EXPECTED
TO DEVELOP AHEAD OF THE SFC WARM FRONT AS STRONG 300K ISENTROPIC
LIFT DEVELOPS IN THE 850-700 MB LAYER. THERE HAS ALSO BEEN A TREND
TOWARD A LATER ARRIVAL OF PCPN INTO UPPER MI WITH THE STRONGER LIFT
CONFINED NEAR THE 850 MB WARM FRONT. THE EFFECTS OF CONVECTION NEAR
THE FRONT AND IN THE WARM SECTOR WHICH MAY LIMIT MOISTURE TRANSPORT
TO THE NORTH ARE OFTEN POORLY HANDLED BY THE MODELS.
SUNDAY AFTERNOON INTO SUNDAY EVENING...AS THE WARM FRONT LIFTS INTO
UPPER MI AND STRONG DYNAMICS ASSOCIATED WITH THE SHRTWV NEAR THE
CWA...PER 00Z/14 GFS AND ECMWF...EXPECT PCPN COVERAGE TO INCREASE.
STRONG UPPER LEVEL DIV WITH A COUPLED JET STRUCTURE AND STRONG
700-300 MB QVECTOR CONV ALONG WITH MOISTURE ADVECTION PUSHING PWAT
VALUES TO NEAR 1.2 INCHES AND 850 MB DEWPOINTS TO 11C...WILL SUPPORT
MODERATE TO HEAVY RAIN SHOWERS...ESPECIALLY OVER THE NW HALF OF THE CWA.
INSTABILITY WILL ALSO INCREASE ENOUGH TO SUPPORT SCT TSRA. GIVEN THE
STRONG SHEAR WITH THE DYNAMIC SYSTEM...SOME ISOLATED SEVERE STORMS
WILL BE POSSIBLE.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 523 AM EDT SAT APR 14 2012
MAIN FCST CONCERNS DURING THIS TIME REVOLVE ARND TRACK OF LO PRES
MOVING THRU THE UPR LKS/ACCOMPANYING PCPN SHIELD/POTENTIAL FOR
WINTRY PCPN.
SUN NGT...00Z MODELS HAVE TRENDED TOWARD A COMMON SCENARIO FOR THE
LO TRACK...WITH THE LO TENDING TO WEAKEN AS IT CROSSES THE CWA TO
NEAR ERY BY 12Z MON AS THE SHRTWV SHEARS OUT IN THE CONFLUENCE ZN ON
THE NW FLANK OF THE SE RDG. DRY SURGE AHEAD OF THIS DISTURBANCE
LOOKS TO IMPACT AT LEAST THE E HALF OF THE CWA MUCH OF THE NGT
BEFORE BACKWASH MSTR UNDER THE SHRTWV ITSELF ROTATES W-E INTO THE W
HALF 06Z-12Z MON. DESPITE SOME RATHER DEEP MSTR...INCRSG DEEP LYR
QVECTOR DVGC SHOWN BY THE 00Z GFS RELATED TO COLD AIR SURGING INTO
THE AREA AS WELL AS H3-2 CNVGC WL TEND TO WORK AGAINST A SGNFT PCPN
EVENT. ALSO SINCE THE LO IS WEAKENING...SOME MODELS HINT THE LLVL
FLOW WL BE ONLY WEAKLY CYC. AS FOR PCPN TYPE...THE NAM/GFS FCST
SDNGS HINT THE INITIAL COOLING WL BE FOCUSED IN THE LLVLS BLO A
LINGERING ELEVATED WARMER LYR. THIS COOLING PROFILE WOULD RESULT IN
AT LEAST A BRIEF PERIOD OF -FZRA/SLEET BEFORE THE PCPN CHGS TO ALL
SN WITH THE ARRIVAL OF THE DEEPER COLD AIR. BUT EVEN IF THERE IS
SOME FZRA...LIMITED PERIOD OF FAVORABLE THERMAL PROFILE/WARM GROUND
FM A WARM SUN AFTN SHOULD LIMIT THE POTENTIAL FOR ANY SGNFT ICING.
MON...AS THE SHRTWV/SFC LO CONTINUE TO SHEAR TO THE E AND WEAKEN...
LINGERING BACKWASH MSTR WL SLOWLY DECAY WITH COMPLETE EXIT OF
QVECTOR CNVGC BY THE AFTN. BUT A FEW INCHES OF WET SNOW COULD
ACCUMULATE OVER THE HIER TERRAIN OF THE NW CWA LATE SUN NGT/MON
MRNG...MAINLY IN AREAS OVER THE HIER TERRAIN OF THE W AND NCNTRL
IMPACTED BY THE UPSLOPE NLY FLOW...ESPECIALLY IF THE SOMEWHAT
STRONGER DYNAMICS INDICATED BY THE 00Z NAM/UKMET MATERIALIZE. BY THE
AFTN...THERE IS LIKELY TO BE SOME SUNSHINE OVER ESPECIALLY THE W AS
MORE ACYC FLOW/DRIER AIR MOVE INTO THAT AREA ON THE SRN FLANK OF
BLDG HI PRES OVER NW ONTARIO. OTRW...A GUSTY N WIND WITH H925 WINDS
ARND 30 KTS WL MAKE THE DAY FEEL ALMOST LIKE MID WINTER.
MON NGT...LARGER SCALE PCPN WL BE OVER WITH DEPARTURE OF DEEP MSTR/
DYNAMICS. BUT SOME LK CLDS WL PERSIST IN AREAS DOWNWIND OF LK SUP
OVER MAINLY THE E HALF UNDER CYC NLY FLOW...WHERE LLVL THERMAL TROF
WL RESIDE WITH H85 TEMPS AS LO AS -10C PER THE GFS. OPTED TO RETAIN
SOME SCHC POPS FOR -SHSN IN THIS AREA AS WELL WITH TEMPS ALMOST COLD
ENUF FOR LES. IN FACT...THE NAM SHOWS H85 TEMPS AS LO AS -12C.
EXPECT THE LOWEST MIN TEMPS CLOSE TO THE LO END OF GUIDANCE OVER THE
INTERIOR W HALF WHERE SKIES ARE MORE LIKELY TO BE MOCLR WITH PWAT
NEAR 0.10 INCH/LGT WINDS CLOSER TO THE RDG AXIS.
EXTENDED...EXPECT A DRY...SEASONABLY CHILLY PERIOD ON TUE INTO TUE
NGT WITH HUDSON BAY HI PRES DOMINATING. NEXT DISTURBANCE IS LIKELY
TO IMPACT THE AREA ON WED...BUT 00Z ECMWF/GFS SHOW RADICALLY
DIFFERENT SCENARIOS FOR THIS DISTURBANCE...SO RELIED ON MODEL
CONSENSUS FOR THE FCST. AFT SOME DRYING ON THU WITH HI PRES
FOLLOWING...THE ECMWF IS MOST AGGRESSIVE AT BRINGING ANOTHER DEEPER
LO THRU THE UPR MIDWEST TO END THE WEEK. IF THIS MODEL IS CORRECT...
UPR MI WOULD SEE SOME SGNFT SN. BUT SINCE THE GFS IS DRY WITH THE
SHRTWV TRACKING MUCH FARTHER TO THE S...WENT WITH MODEL BLEND.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 123 PM EDT SAT APR 14 2012
CLOUDS ASSOCIATED WITH THE DEPARTING SYSTEM HAVE CLEARED ALL SITES.
EXPECT VFR CONDITIONS ACROSS THE AREA THROUGH THE EVENING...WITH
SOME DAYTIME CUMULUS CLOUDS AT 5-7KFT DISSIPATING BY EARLY THIS
EVENING. MAIN CONCERN TODAY IS THE STRONGER WINDS THAT ARE CURRENTLY
GUSTING TO AROUND 30KTS AT ALL SITES. THESE WINDS MAY DECREASE
SLIGHTLY LATE THIS AFTERNOON AS THE PRESSURE GRADIENT RELAXES...BUT
DO NOT EXPECT THEM TO DROP BELOW 12KTS UNTIL WEAKER PRESSURE
GRADIENT AND NOCTURNAL COOLING TAKE HOLD AROUND SUNSET. MID CLOUDS
SHOULD INCREASE LATE TONIGHT AHEAD OF A WARM FRONT. THEN...ABUNDANT
MOISTURE AND SCATTERED SHOWERS WITH ISOLATED THUNDERSTORMS WILL
SPREAD FROM SOUTH TO NORTH ACROSS UPPER MI AROUND 12Z. FAVORABLE
UPSLOPE FLOW AT CMX AND SAW SHOULD BRING DOWN CIGS BELOW 1KFT
THROUGHOUT THE MORNING. THERE IS ALSO A POTENTIAL THAT SOME
THUNDERSTORMS COULD BECOME STRONG ACROSS SOUTH CENTRAL UPPER MI AND
POSSIBLY AFFECT SAW FROM LATE AFTERNOON INTO THE EVENING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 523 AM EDT SAT APR 14 2012
SE WINDS GUSTING TO 20 KT WILL BECOME SW TODAY AS A TROUGH MOVES
THROUGH THE AREA. NORTHEAST WINDS WILL INCREASE TO 30 KT OVER WRN
LAKE SUPERIOR SUNDAY AFTERNOON AHEAD OF LOW PRESSURE MOVING TOWARD THE
UPPER MS VALLEY. EXPECT A N TO NE GALE OVER A GOOD PORTION OF MAINLY
THE CENTRAL LK ON LATE SUN NIGHT INTO MON WITH SHARPENING PRES
GRADIENT BETWEEN DEPARTING LO PRES AND HI PRES BUILDING INTO ONTARIO.
SHARP SURGE OF COLD AIR WILL ENHANCE MIXING OF HIER WINDS TO THE SFC.
THE APPROACH OF THE HI PRES RIDGE WILL CAUSE DIMINISHING WINDS BY MON
NIGHT. RELATIVELY LIGHT WINDS WILL CONTINUE THRU MID WEEK.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
SHORT TERM...JLB
LONG TERM...KC
AVIATION...TK
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
724 AM EDT SAT APR 14 2012
.SYNOPSIS...
ISSUED AT 523 AM EDT SAT APR 14 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH OVER
THE WRN CONUS AND A RIDGE FROM THE GULF OF MEXICO THROUGH THE CNTRL
GREAT LAKES. A WELL-DEFINED SHRTWV OVER CNTRL WI SUPPORTED A SCT
BAND OF SHOWERS FROM WRN UPPER MI INTO SRN WI. A VERY POTENT
UPSTREAM SHRTWV THAT WILL IMPACT WX OVER THE WRN GREAT LAKES SUN
INTO SUN NIGHT WAS MOVING THROUGH WRN AZ. AT THE SFC...SRLY FLOW
PREVAILED THROUGH UPPER MI AHEAD OF A LOW OVER NW MN.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 523 AM EDT SAT APR 14 2012TODAY THROUGH SUNDAY EVENING
TODAY...ANY LINGERING SCT PCPN OVER THE NRN AND ERN FCST AREA WILL
MOVE OUT DURING THE MORNING AS THE DRY SLOT UNDERNEATH UPPER LEVEL
JET STREAK SHIFTS OVER THE AREA. EXPECT CLOUDS TO CLEAR OUT DURING
THE MORNING...PER UPSTREAM OBS OVER MN. WITH SUNSHINE AND DECENT
MIXING TEMPS SHOULD CLIMB TO AROUND 70 INLAND WITH DEWPOINTS FALLING
INTO THE MID 30S. WITH RH VALUES INTO THE 25 TO 30 PERCENT RANGE AND
GUSTY WSW WINDS...THERE WILL BE AN ELEVATED RISK OF WILDFIRES SAT
AFTERNOON...ESPECIALLY OVER THE W HALF WHERE TEMPS/WINDS WILL BE
HIGHEST.
TONIGHT INTO SUNDAY...AS THE SW CONUS SHORTWAVE LIFTS NE OUT OF THE
ROCKIES AND THROUGH THE PLAINS...SFC LOW PRES WILL DEVELOP OVER
NEBRASKA AND MOVE INTO THE UPPER MS VALLEY. THE MODELS HAVE TRENDED
STRONGER WITH THE SHORTWAVE AND MORE TO THE NW WITH THE SFC LOW AND
ASSOCIATED WARM FRONT INTO THE WRN GREAT LAKES WHICH SEEMS
REASONABLE GIVEN THE STRENGTH OF THE SHORTWAVE AND PROMINENT RIDGE
OVER THE SOUTHEAST INTO THE LAKES. A LARGE AREA OF PCPN IS EXPECTED
TO DEVELOP AHEAD OF THE SFC WARM FRONT AS STRONG 300K ISENTROPIC
LIFT DEVELOPS IN THE 850-700 MB LAYER. THERE HAS ALSO BEEN A TREND
TOWARD A LATER ARRIVAL OF PCPN INTO UPPER MI WITH THE STRONGER LIFT
CONFINED NEAR THE 850 MB WARM FRONT. THE EFFECTS OF CONVECTION NEAR
THE FRONT AND IN THE WARM SECTOR WHICH MAY LIMIT MOISTURE TRANSPORT
TO THE NORTH ARE OFTEN POORLY HANDLED BY THE MODELS.
SUNDAY AFTERNOON INTO SUNDAY EVENING...AS THE WARM FRONT LIFTS INTO
UPPER MI AND STRONG DYNAMICS ASSOCIATED WITH THE SHRTWV NEAR THE
CWA...PER 00Z/14 GFS AND ECMWF...EXPECT PCPN COVERAGE TO INCREASE.
STRONG UPPER LEVEL DIV WITH A COUPLED JET STRUCTURE AND STRONG
700-300 MB QVECTOR CONV ALONG WITH MOISTURE ADVECTION PUSHING PWAT
VALUES TO NEAR 1.2 INCHES AND 850 MB DEWPOINTS TO 11C...WILL SUPPORT
MODERATE TO HEAVY RAIN SHOWERS...ESPECIALLY OVER THE NW HALF OF THE CWA.
INSTABILITY WILL ALSO INCREASE ENOUGH TO SUPPORT SCT TSRA. GIVEN THE
STRONG SHEAR WITH THE DYNAMIC SYSTEM...SOME ISOLATED SEVERE STORMS
WILL BE POSSIBLE.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 523 AM EDT SAT APR 14 2012
MAIN FCST CONCERNS DURING THIS TIME REVOLVE ARND TRACK OF LO PRES
MOVING THRU THE UPR LKS/ACCOMPANYING PCPN SHIELD/POTENTIAL FOR
WINTRY PCPN.
SUN NGT...00Z MODELS HAVE TRENDED TOWARD A COMMON SCENARIO FOR THE
LO TRACK...WITH THE LO TENDING TO WEAKEN AS IT CROSSES THE CWA TO
NEAR ERY BY 12Z MON AS THE SHRTWV SHEARS OUT IN THE CONFLUENCE ZN ON
THE NW FLANK OF THE SE RDG. DRY SURGE AHEAD OF THIS DISTURBANCE
LOOKS TO IMPACT AT LEAST THE E HALF OF THE CWA MUCH OF THE NGT
BEFORE BACKWASH MSTR UNDER THE SHRTWV ITSELF ROTATES W-E INTO THE W
HALF 06Z-12Z MON. DESPITE SOME RATHER DEEP MSTR...INCRSG DEEP LYR
QVECTOR DVGC SHOWN BY THE 00Z GFS RELATED TO COLD AIR SURGING INTO
THE AREA AS WELL AS H3-2 CNVGC WL TEND TO WORK AGAINST A SGNFT PCPN
EVENT. ALSO SINCE THE LO IS WEAKENING...SOME MODELS HINT THE LLVL
FLOW WL BE ONLY WEAKLY CYC. AS FOR PCPN TYPE...THE NAM/GFS FCST
SDNGS HINT THE INITIAL COOLING WL BE FOCUSED IN THE LLVLS BLO A
LINGERING ELEVATED WARMER LYR. THIS COOLING PROFILE WOULD RESULT IN
AT LEAST A BRIEF PERIOD OF -FZRA/SLEET BEFORE THE PCPN CHGS TO ALL
SN WITH THE ARRIVAL OF THE DEEPER COLD AIR. BUT EVEN IF THERE IS
SOME FZRA...LIMITED PERIOD OF FAVORABLE THERMAL PROFILE/WARM GROUND
FM A WARM SUN AFTN SHOULD LIMIT THE POTENTIAL FOR ANY SGNFT ICING.
MON...AS THE SHRTWV/SFC LO CONTINUE TO SHEAR TO THE E AND WEAKEN...
LINGERING BACKWASH MSTR WL SLOWLY DECAY WITH COMPLETE EXIT OF
QVECTOR CNVGC BY THE AFTN. BUT A FEW INCHES OF WET SNOW COULD
ACCUMULATE OVER THE HIER TERRAIN OF THE NW CWA LATE SUN NGT/MON
MRNG...MAINLY IN AREAS OVER THE HIER TERRAIN OF THE W AND NCNTRL
IMPACTED BY THE UPSLOPE NLY FLOW...ESPECIALLY IF THE SOMEWHAT
STRONGER DYNAMICS INDICATED BY THE 00Z NAM/UKMET MATERIALIZE. BY THE
AFTN...THERE IS LIKELY TO BE SOME SUNSHINE OVER ESPECIALLY THE W AS
MORE ACYC FLOW/DRIER AIR MOVE INTO THAT AREA ON THE SRN FLANK OF
BLDG HI PRES OVER NW ONTARIO. OTRW...A GUSTY N WIND WITH H925 WINDS
ARND 30 KTS WL MAKE THE DAY FEEL ALMOST LIKE MID WINTER.
MON NGT...LARGER SCALE PCPN WL BE OVER WITH DEPARTURE OF DEEP MSTR/
DYNAMICS. BUT SOME LK CLDS WL PERSIST IN AREAS DOWNWIND OF LK SUP
OVER MAINLY THE E HALF UNDER CYC NLY FLOW...WHERE LLVL THERMAL TROF
WL RESIDE WITH H85 TEMPS AS LO AS -10C PER THE GFS. OPTED TO RETAIN
SOME SCHC POPS FOR -SHSN IN THIS AREA AS WELL WITH TEMPS ALMOST COLD
ENUF FOR LES. IN FACT...THE NAM SHOWS H85 TEMPS AS LO AS -12C.
EXPECT THE LOWEST MIN TEMPS CLOSE TO THE LO END OF GUIDANCE OVER THE
INTERIOR W HALF WHERE SKIES ARE MORE LIKELY TO BE MOCLR WITH PWAT
NEAR 0.10 INCH/LGT WINDS CLOSER TO THE RDG AXIS.
EXTENDED...EXPECT A DRY...SEASONABLY CHILLY PERIOD ON TUE INTO TUE
NGT WITH HUDSON BAY HI PRES DOMINATING. NEXT DISTURBANCE IS LIKELY
TO IMPACT THE AREA ON WED...BUT 00Z ECMWF/GFS SHOW RADICALLY
DIFFERENT SCENARIOS FOR THIS DISTURBANCE...SO RELIED ON MODEL
CONSENSUS FOR THE FCST. AFT SOME DRYING ON THU WITH HI PRES
FOLLOWING...THE ECMWF IS MOST AGGRESSIVE AT BRINGING ANOTHER DEEPER
LO THRU THE UPR MIDWEST TO END THE WEEK. IF THIS MODEL IS CORRECT...
UPR MI WOULD SEE SOME SGNFT SN. BUT SINCE THE GFS IS DRY WITH THE
SHRTWV TRACKING MUCH FARTHER TO THE S...WENT WITH MODEL BLEND.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 723 AM EDT SAT APR 14 2012
SATELLITE IMAGERY AND UPSTREAM OBS INDICATE THAT LOWER END MVFR AND
EVEN SOME IFR CIGS OVER WI WERE RAPIDLY GIVING WAY TO CLEARING AS A
TROUGH MOVES THROUGH. SO...EXPECT THAT A PERIOD OF MVRR CIGS AT THE
TAF SITES EARLY TODAY WILL ALSO SCT OUT QUICKLY BY MID TO LATE
MORNING AS DRYING OF THE COLUMN UNDERNEATH THE UPPER JET STREAK
TAKES OVER. WINDS WILL BE GUSTY TODAY...ESPECIALLY AT KCMX UNDER A
MORE FAVORABLE WRLY FLOW THERE. MID CLOUDS SHOULD INCREASE LATE
TONIGHT AHEAD OF A WARM FRONT. HOWEVER...PCPN AND ANY LOWER CIGS ARE
EXPECTED TO HOLD OFF UNTIL AFTER 12Z.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 523 AM EDT SAT APR 14 2012
SE WINDS GUSTING TO 20 KT WILL BECOME SW TODAY AS A TROUGH MOVES
THROUGH THE AREA. NORTHEAST WINDS WILL INCREASE TO 30 KT OVER WRN
LAKE SUPERIOR SUNDAY AFTERNOON AHEAD OF LOW PRESSURE MOVING TOWARD THE
UPPER MS VALLEY. EXPECT A N TO NE GALE OVER A GOOD PORTION OF MAINLY
THE CENTRAL LK ON LATE SUN NIGHT INTO MON WITH SHARPENING PRES
GRADIENT BETWEEN DEPARTING LO PRES AND HI PRES BUILDING INTO ONTARIO.
SHARP SURGE OF COLD AIR WILL ENHANCE MIXING OF HIER WINDS TO THE SFC.
THE APPROACH OF THE HI PRES RIDGE WILL CAUSE DIMINISHING WINDS BY MON
NIGHT. RELATIVELY LIGHT WINDS WILL CONTINUE THRU MID WEEK.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
SHORT TERM...JLB
LONG TERM...KC
AVIATION...JLB
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
527 AM EDT SAT APR 14 2012
.SYNOPSIS...
ISSUED AT 523 AM EDT SAT APR 14 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH OVER
THE WRN CONUS AND A RIDGE FROM THE GULF OF MEXICO THROUGH THE CNTRL
GREAT LAKES. A WELL-DEFINED SHRTWV OVER CNTRL WI SUPPORTED A SCT
BAND OF SHOWERS FROM WRN UPPER MI INTO SRN WI. A VERY POTENT
UPSTREAM SHRTWV THAT WILL IMPACT WX OVER THE WRN GREAT LAKES SUN
INTO SUN NIGHT WAS MOVING THROUGH WRN AZ. AT THE SFC...SRLY FLOW
PREVAILED THROUGH UPPER MI AHEAD OF A LOW OVER NW MN.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 523 AM EDT SAT APR 14 2012TODAY THROUGH SUNDAY EVENING
TODAY...ANY LINGERING SCT PCPN OVER THE NRN AND ERN FCST AREA WILL
MOVE OUT DURING THE MORNING AS THE DRY SLOT UNDERNEATH UPPER LEVEL
JET STREAK SHIFTS OVER THE AREA. EXPECT CLOUDS TO CLEAR OUT DURING
THE MORNING...PER UPSTREAM OBS OVER MN. WITH SUNSHINE AND DECENT
MIXING TEMPS SHOULD CLIMB TO AROUND 70 INLAND WITH DEWPOINTS FALLING
INTO THE MID 30S. WITH RH VALUES INTO THE 25 TO 30 PERCENT RANGE AND
GUSTY WSW WINDS...THERE WILL BE AN ELEVATED RISK OF WILDFIRES SAT
AFTERNOON...ESPECIALLY OVER THE W HALF WHERE TEMPS/WINDS WILL BE
HIGHEST.
TONIGHT INTO SUNDAY...AS THE SW CONUS SHORTWAVE LIFTS NE OUT OF THE
ROCKIES AND THROUGH THE PLAINS...SFC LOW PRES WILL DEVELOP OVER
NEBRASKA AND MOVE INTO THE UPPER MS VALLEY. THE MODELS HAVE TRENDED
STRONGER WITH THE SHORTWAVE AND MORE TO THE NW WITH THE SFC LOW AND
ASSOCIATED WARM FRONT INTO THE WRN GREAT LAKES WHICH SEEMS
REASONABLE GIVEN THE STRENGTH OF THE SHORTWAVE AND PROMINENT RIDGE
OVER THE SOUTHEAST INTO THE LAKES. A LARGE AREA OF PCPN IS EXPECTED
TO DEVELOP AHEAD OF THE SFC WARM FRONT AS STRONG 300K ISENTROPIC
LIFT DEVELOPS IN THE 850-700 MB LAYER. THERE HAS ALSO BEEN A TREND
TOWARD A LATER ARRIVAL OF PCPN INTO UPPER MI WITH THE STRONGER LIFT
CONFINED NEAR THE 850 MB WARM FRONT. THE EFFECTS OF CONVECTION NEAR
THE FRONT AND IN THE WARM SECTOR WHICH MAY LIMIT MOISTURE TRANSPORT
TO THE NORTH ARE OFTEN POORLY HANDLED BY THE MODELS.
SUNDAY AFTERNOON INTO SUNDAY EVENING...AS THE WARM FRONT LIFTS INTO
UPPER MI AND STRONG DYNAMICS ASSOCIATED WITH THE SHRTWV NEAR THE
CWA...PER 00Z/14 GFS AND ECMWF...EXPECT PCPN COVERAGE TO INCREASE.
STRONG UPPER LEVEL DIV WITH A COUPLED JET STRUCTURE AND STRONG
700-300 MB QVECTOR CONV ALONG WITH MOISTURE ADVECTION PUSHING PWAT
VALUES TO NEAR 1.2 INCHES AND 850 MB DEWPOINTS TO 11C...WILL SUPPORT
MODERATE TO HEAVY RAIN SHOWERS...ESPECIALLY OVER THE NW HALF OF THE CWA.
INSTABILITY WILL ALSO INCREASE ENOUGH TO SUPPORT SCT TSRA. GIVEN THE
STRONG SHEAR WITH THE DYNAMIC SYSTEM...SOME ISOLATED SEVERE STORMS
WILL BE POSSIBLE.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 523 AM EDT SAT APR 14 2012
MAIN FCST CONCERNS DURING THIS TIME REVOLVE ARND TRACK OF LO PRES
MOVING THRU THE UPR LKS/ACCOMPANYING PCPN SHIELD/POTENTIAL FOR
WINTRY PCPN.
SUN NGT...00Z MODELS HAVE TRENDED TOWARD A COMMON SCENARIO FOR THE
LO TRACK...WITH THE LO TENDING TO WEAKEN AS IT CROSSES THE CWA TO
NEAR ERY BY 12Z MON AS THE SHRTWV SHEARS OUT IN THE CONFLUENCE ZN ON
THE NW FLANK OF THE SE RDG. DRY SURGE AHEAD OF THIS DISTURBANCE
LOOKS TO IMPACT AT LEAST THE E HALF OF THE CWA MUCH OF THE NGT
BEFORE BACKWASH MSTR UNDER THE SHRTWV ITSELF ROTATES W-E INTO THE W
HALF 06Z-12Z MON. DESPITE SOME RATHER DEEP MSTR...INCRSG DEEP LYR
QVECTOR DVGC SHOWN BY THE 00Z GFS RELATED TO COLD AIR SURGING INTO
THE AREA AS WELL AS H3-2 CNVGC WL TEND TO WORK AGAINST A SGNFT PCPN
EVENT. ALSO SINCE THE LO IS WEAKENING...SOME MODELS HINT THE LLVL
FLOW WL BE ONLY WEAKLY CYC. AS FOR PCPN TYPE...THE NAM/GFS FCST
SDNGS HINT THE INITIAL COOLING WL BE FOCUSED IN THE LLVLS BLO A
LINGERING ELEVATED WARMER LYR. THIS COOLING PROFILE WOULD RESULT IN
AT LEAST A BRIEF PERIOD OF -FZRA/SLEET BEFORE THE PCPN CHGS TO ALL
SN WITH THE ARRIVAL OF THE DEEPER COLD AIR. BUT EVEN IF THERE IS
SOME FZRA...LIMITED PERIOD OF FAVORABLE THERMAL PROFILE/WARM GROUND
FM A WARM SUN AFTN SHOULD LIMIT THE POTENTIAL FOR ANY SGNFT ICING.
MON...AS THE SHRTWV/SFC LO CONTINUE TO SHEAR TO THE E AND WEAKEN...
LINGERING BACKWASH MSTR WL SLOWLY DECAY WITH COMPLETE EXIT OF
QVECTOR CNVGC BY THE AFTN. BUT A FEW INCHES OF WET SNOW COULD
ACCUMULATE OVER THE HIER TERRAIN OF THE NW CWA LATE SUN NGT/MON
MRNG...MAINLY IN AREAS OVER THE HIER TERRAIN OF THE W AND NCNTRL
IMPACTED BY THE UPSLOPE NLY FLOW...ESPECIALLY IF THE SOMEWHAT
STRONGER DYNAMICS INDICATED BY THE 00Z NAM/UKMET MATERIALIZE. BY THE
AFTN...THERE IS LIKELY TO BE SOME SUNSHINE OVER ESPECIALLY THE W AS
MORE ACYC FLOW/DRIER AIR MOVE INTO THAT AREA ON THE SRN FLANK OF
BLDG HI PRES OVER NW ONTARIO. OTRW...A GUSTY N WIND WITH H925 WINDS
ARND 30 KTS WL MAKE THE DAY FEEL ALMOST LIKE MID WINTER.
MON NGT...LARGER SCALE PCPN WL BE OVER WITH DEPARTURE OF DEEP MSTR/
DYNAMICS. BUT SOME LK CLDS WL PERSIST IN AREAS DOWNWIND OF LK SUP
OVER MAINLY THE E HALF UNDER CYC NLY FLOW...WHERE LLVL THERMAL TROF
WL RESIDE WITH H85 TEMPS AS LO AS -10C PER THE GFS. OPTED TO RETAIN
SOME SCHC POPS FOR -SHSN IN THIS AREA AS WELL WITH TEMPS ALMOST COLD
ENUF FOR LES. IN FACT...THE NAM SHOWS H85 TEMPS AS LO AS -12C.
EXPECT THE LOWEST MIN TEMPS CLOSE TO THE LO END OF GUIDANCE OVER THE
INTERIOR W HALF WHERE SKIES ARE MORE LIKELY TO BE MOCLR WITH PWAT
NEAR 0.10 INCH/LGT WINDS CLOSER TO THE RDG AXIS.
EXTENDED...EXPECT A DRY...SEASONABLY CHILLY PERIOD ON TUE INTO TUE
NGT WITH HUDSON BAY HI PRES DOMINATING. NEXT DISTURBANCE IS LIKELY
TO IMPACT THE AREA ON WED...BUT 00Z ECMWF/GFS SHOW RADICALLY
DIFFERENT SCENARIOS FOR THIS DISTURBANCE...SO RELIED ON MODEL
CONSENSUS FOR THE FCST. AFT SOME DRYING ON THU WITH HI PRES
FOLLOWING...THE ECMWF IS MOST AGGRESSIVE AT BRINGING ANOTHER DEEPER
LO THRU THE UPR MIDWEST TO END THE WEEK. IF THIS MODEL IS CORRECT...
UPR MI WOULD SEE SOME SGNFT SN. BUT SINCE THE GFS IS DRY WITH THE
SHRTWV TRACKING MUCH FARTHER TO THE S...WENT WITH MODEL BLEND.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 131 AM EDT SAT APR 14 2012
LOW-LEVEL MOISTURE IS MOVING NE PER OBS/SATELLITE AND SHOULD RESULT
IN CIGS DROPPING TO MVFR OVERNIGHT. ON SAT...DRYING OF THE COLUMN
UNDERNEATH UPPER JET STREAK WILL RESULT IN IMPROVEMENT TO VFR IN THE
MORNING HRS. WINDS WILL BE GUSTY SAT...ESPECIALLY AT KCMX UNDER A
MORE FAVORABLE WRLY FLOW THERE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 523 AM EDT SAT APR 14 2012
SE WINDS GUSTING TO 20 KT WILL BECOME SW TODAY AS A TROUGH MOVES
THROUGH THE AREA. NORTHEAST WINDS WILL INCREASE TO 30 KT OVER WRN
LAKE SUPERIOR SUNDAY AFTERNOON AHEAD OF LOW PRESSURE MOVING TOWARD THE
UPPER MS VALLEY. EXPECT A N TO NE GALE OVER A GOOD PORTION OF MAINLY
THE CENTRAL LK ON LATE SUN NIGHT INTO MON WITH SHARPENING PRES
GRADIENT BETWEEN DEPARTING LO PRES AND HI PRES BUILDING INTO ONTARIO.
SHARP SURGE OF COLD AIR WILL ENHANCE MIXING OF HIER WINDS TO THE SFC.
THE APPROACH OF THE HI PRES RIDGE WILL CAUSE DIMINISHING WINDS BY MON
NIGHT. RELATIVELY LIGHT WINDS WILL CONTINUE THRU MID WEEK.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
SHORT TERM...JLB
LONG TERM...KC
AVIATION...VOSS
MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
132 AM EDT SAT APR 14 2012
.SHORT TERM...(THIS EVENING THROUGH SATURDAY)
ISSUED AT 417 PM EDT FRI APR 13 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW MID/UPPER LEVEL TROF OVER
THE WRN CONUS WITH DOWNSTREAM RIDGE FROM THE WRN GULF TO THE WRN
LAKES. VIGOROUS LOOKING SHORTWAVE WAS LIFTING NNE THRU SW MN.
DESPITE VIGOROUS LOOK...SHRA AHEAD OF FEATURE HAVE BEEN WEAKENING AS
THEY MOVE E INTO THE VERY DRY AIRMASS ASSOCIATED WITH RIDGE PER 12Z
KGRB SOUNDING. THIS TREND WILL LIKELY CONTINUE AS SHORTWAVE
PROGRESSES INTO THE MEAN RIDGE POSITION...ESPECIALLY WITH 850MB FLOW
VEERING MORE WRLY AND MOISTURE TRANSPORT WEAKENING WITH TIME. SHRA
CURRENTLY DEVELOPING AROUND VORT MAX IN SW MN MAY BRUSH THE NW FCST
AREA DURING THE NIGHT. AT THIS POINT...IT DOESN`T LOOK LIKE ANYTHING
HIGHER THAN CHC/SCT POPS ARE WARRANTED. WHERE PCPN OCCURS...AMOUNTS
WILL BE LIGHT...UNDER 0.1 INCHES.
SAT...ANY LINGERING SCT PCPN OVER THE NRN AND ERN FCST AREA WILL
MOVE OUT DURING THE MORNING AS DRY SLOT UNDERNEATH UPPER LEVEL JET
STREAK SHIFTS OVER THE AREA. DRYING COLUMN AND TREND TO MOSTLY SUNNY
SHOULD ALLOW FOR DEEP MIXING TO AT OR ABOVE 800MB SAT AFTN. PER FCST
SOUNDINGS...THIS WILL ALLOW TEMPS TO RISE TO AROUND 70F AWAY FROM
MARINE INFLUENCES. MIXING WILL HELP DWPTS FALL IN THE AFTN. IF
MIXING HEIGHTS ARE A LITTLE HIGHER THAN EXPECTED...DWPTS WILL FALL
SEVERAL DEGREES MORE THAN REFLECTED IN THIS FCST ISSUANCE. AS IT IS
NOW...HAVE RH FALLING TO AROUND 30PCT. WITH GUSTY WSW WINDS...THERE
WILL BE AN ELEVATED RISK OF WILDFIRES SAT AFTN...ESPECIALLY OVER THE
W HALF WHERE TEMPS/WINDS WILL BE HIGHEST.
.LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY)
ISSUED AT 417 PM EDT FRI APR 13 2012
MAIN ISSUE FOR THE LONG TERM PERIOD IS THE SUNDAY/MONDAY TIME
FRAME AS DEEP WESTERN TROUGHS HEADS EAST INTO THE LARGE RIDGE
OVR THE EASTERN CONUS. SHORTWAVE TROUGH CURRENTLY BRINGING RAIN
AND TSRA TO SOUTHERN CALIFORNIA IS FCST TO DIG INTO FOUR CORNERS
AREA ON SATURDAY THEN LIFT INTO THE UPPER MISSISSIPPI RIVER VALLEY
BY LATER SUNDAY. IN THE LOW-LEVELS SFC-H85 LOWS FORM OVER SOUTHERN
PLAINS WHILE WARM FRONT BULGES AS FAR NORTH AS NEB AND IA BY
SATURDAY EVENING. POSITIVES FOR PRECIPITATION ON SATURDAY NIGHT IS
FACT THAT UPR MI IS WITHIN BROAD AREA OF DIVERGENCE ALOFT DUE TO JET
STREAK LIFTING ACROSS ONTARIO AND ANOTHER NOSING IN FM THE SOUTHERN
PLAINS. H85 THETA-E ADVECTION ALSO FCST TO ROLL ACROSS UPR LAKES.
WHILE THIS AND THE DIVERGENCE ALOFT MAY HELP TRIGGER AT LEAST SCT
SHOWERS...EXPECT BETTER RAIN CHANCES OVER SOUTH AND EAST CWA CLOSER
TO MAXIMUM H85-H7 MOISTURE TRANSPORT. PTYPE THIS FIRST BATCH OF
PRECIP STRICTLY RAIN AS H85 TEMPS ARE AOA +5C AND SFC DWPNTS REMAIN
AOA 40F. PROBABLY WILL BE A BREAK IN SHOWERS LATE SATURDAY NIGHT
INTO SUN MORNING...BUT GIVEN PERSISTENT H85 THETA-E ADVECTION AND
THAT UPR JET FORCING STILL AROUND FCST WILL KEEP BROADBRUSHED CHANCE
POPS.
LATER SUNDAY...ATTN IS SQUARELY ON APPROACHING DEEP SHORTWAVE TROUGH
LIFTING INTO VCNTY OF NORTHEAST NEB INTO SOUTHWEST MN. SFC LOW FCST
TO PUSH INTO WCNTRL WI BY AFTN WHILE WARM FRONT ATTM IS FCST TO LIFT
INTO NORTHERN WI AND PERHAPS SCNTRL UPR MI. TREND FM LATEST MODELS
IS FOR 12Z NAM/GFS TO BRING SFC LOW NEAR IMT BY 00Z. GIVEN SE WINDS
OFF LK MICHIGAN WOULD EXPECT THE WARM FRONT TO STRUGGLE ANY FARTHER
NORTH AND EAST. CONVECTION SHOULD BE ONGOING AND/OR RE-DEVELOPING
SUNDAY AFTN AHEAD OF PRE-FRONTAL DRY LINE SLIDING ACROSS SOUTHERN
MN INTO IA. SW H85-H7 WINDS WILL ADVECT CONVECTION INTO CWA LATER
IN THE DAY WITH INCREASING POTENTIAL OF SEVERE STORMS IF THE WARM
FRONT IS INDEED OVR NORTHERN WI/SOUTH CNTRL UPR MI GIVEN STEEP H7-H5
LAPSE RATES AOA 7C/KM JUST UPSTREAM. ALL EVENTS ARE DIFFERENT...BUT
SHOULD NOTE THAT THE UPR LEVEL AND MSLP/T/TD PATTERN LOOK SOMEWHAT
SIMILAR TO 10 APRIL 2011 WHEN A COUPLE CLUSTERS OF SEVERE STORMS
IMPACTED PORTIONS OF NORTHERN WISCONSIN AND SOME HAIL AFFECTED
PORTIONS OF CWA. SVR THREAT FOR CWA WILL LARGELY DEPEND ON HOW FAR
NORTH WARM FRONT MAKES IT.
THIS IS DYNAMIC/SPRING PATTERN FOR SURE. 24-HOURS AGO IT LOOKED MAIN
IMPACT FM THE SYSTEM WOULD BE ACCUMULATING SNOW SUNDAY NIGHT INTO
MONDAY. NOW...THERE COULD BE SEVERE WX SUNDAY THEN POSSIBILITY OF
SNOW LATE SUNDAY NIGHT AND MONDAY MORNING. FARTHER NORTH TRACK TO
SFC LOW WOULD DELAY THE CHANGEOVER TO SNOW UNTIL AFTER MIDNIGHT OVER
ONLY THE FAR WEST PORTION OF UPR MI. ALSO...THE FARTHER NORTH H85
BAROCLINIC ZONE RESULTS IN FARTHER NORTH DEFORMATION PRECIPITATION
AREA...SO MODELS HAVE TRENDED LESS WITH PRECIPITATION OVERNIGHT
SUNDAY NIGHT WHEN THE CHANGEOVER TO SNOW WOULD OCCUR. BLEND OF
LATEST GFS/ECMWF/CANADIAN WOULD POINT TO A FEW INCHES OF SNOW
POSSIBLE IN THE WEST AND MAYBE NORTH CENTRAL CWA LATER SUNDAY NIGHT
INTO MONDAY MORNING. FINAL VERDICT WITH SPECIFICS OF THE SYSTEM ARE
FAR FM IN...SO WILL ONLY TWEAK FCST GIVEN THE LATEST MODEL TRENDS.
WILL CONTINUE TO MENTION ACCUMULATING SNOW IN HWO. ALSO WILL PUT A
MENTION OF STORMS AND POSSIBLE HAIL FOR SUNDAY.
IN THE EXTENDED...ONCE LOW BLOWS BY UPR LAKES...A DRY AND CHILLY
PATTERN IS EXPECTED TUESDAY INTO WEDNESDAY MORNING AS HIGH PRESSURE
DRIFTS ACROSS ONTARIO AND UPR GREAT LAKES. NEXT CHANCE OF RAIN
ARRIVES LATER WEDNESDAY AS SHORTWAVE AND SFC TROUGH PRESS INTO UPR
GREAT LAKES IN INCREASINLY QUICK WNW FLOW ALOFT. ANOTHER COUPLE
DISTURBANCES COULD BRING MORE PRECIPITATION BACK TO THE UPR LAKES
THURSDAY INTO FRIDAY AS WELL THOUGH TIMING IS STILL UNCERTAIN.
CONSENESUS GIVES 20-30 POPS FOR NOW WHICH IS FINE. CORE OF COOLER
AIR LURKING JUST NORTH OF LK SUPERIOR LATE IN THE WEEK COULD LEAD TO
RAIN/SNOW WITH THE SYSTEMS AS THEY MOVE THOUGH DEPENDING ON TIME OF
DAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 131 AM EDT SAT APR 14 2012
LOW-LEVEL MOISTURE IS MOVING NE PER OBS/SATELLITE AND SHOULD RESULT
IN CIGS DROPPING TO MVFR OVERNIGHT. ON SAT...DRYING OF THE COLUMN
UNDERNEATH UPPER JET STREAK WILL RESULT IN IMPROVEMENT TO VFR IN THE
MORNING HRS. WINDS WILL BE GUSTY SAT...ESPECIALLY AT KCMX UNDER A
MORE FAVORABLE WRLY FLOW THERE.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 417 PM EDT FRI APR 13 2012
SOUTHEASTERLY WINDS WILL BE IN THE 15-25KT RANGE AT TIMES OVER MUCH
OF LAKE SUPERIOR TONIGHT AS LOW PRES LIFTS FROM THE ERN DAKOTAS TO
NRN ONTARIO. MIGHT SEE GUSTS AROUND 30KT AT THE HIGHEST OBSERVING
PLATFORMS. AS THE LOW MOVES TO NRN ONTARIO SAT...WINDS WILL SHIFT
AROUND TO THE SW...FAVORING THE W HALF OF LAKE SUPERIOR FOR STRONGER
WINDS...AGAIN INTO THE 15-25KT RANGE AT TIMES. MIGHT SEE SOME GUSTS
TO AROUND 30KT AT THE HIGHEST OBSERVING PLATFORMS THRU ABOUT MID
AFTN DUE TO FAVORABLE ISALLOBARIC COMPONENT. BTWN SYSTEMS...THERE
WILL BE A BRIEF PERIOD OF LIGHTER WINDS UNDER 15KT SAT NIGHT.
ATTENTION THEN TURNS TO THE NEXT LOW PRES SYSTEM THAT WILL MOVE ENE
FROM THE CNTRL PLAINS LATE SAT NIGHT. NE WINDS MAY REACH GALE FORCE
LATE SUN ACROSS W AND CNTRL LAKE SUPERIOR ON THE NW FLANK OF THE LOW
MOVING THRU THE GREAT LAKES. GALES SHOULD THEN SHIFT TO ERN LAKE
SUPERIOR EARLY MON AS WINDS BACK TO THE N BEHIND THE DEPARTING LOW.
WINDS WILL DROP BACK UNDER 20KT TUE AS HIGH PRES ARRIVES...AND THE
LIGHTER WINDS SHOULD LINGER INTO WED.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...VOSS
MARINE...ROLFSON
AREA FORECAST DISCUSSION...UPDATED FOR 00Z TAFS
NWS TWIN CITIES/CHANHASSEN MN
720 PM CDT SUN APR 15 2012
.DISCUSSION...ISSUED 402 PM CDT
MAIN EMPHASIS IS IN THE SHORT TERM WITH A GOOD CHANCE FOR SEVERE
WEATHER THIS AFTERNOON AND EARLY EVENING...RAIN OVERNIGHT...AND A
BRIEF CHANGE OVER TO SNOW MONDAY MORNING BEFORE THE PRECIP MOVES
OUT.
TORNADO WATCH IS IN EFFECT THIS AFTERNOON/EVENING. VISIBLE
SATELLITE CONTINUES TO SHOW GOOD CLEARING AND DESTABILIZATION IN
THE WARM SECTOR WITH GOOD DRYING ALONG WITH 20-40M 500MB HEIGHT
FALLS SHOWING UP IN WESTERN IA. THE WARM FRONT STRETCHES FROM
SOUTHWEST MN UP THROUGH THE NORTHERN TWIN CITIES METRO AND INTO
WEST CENTRAL WI. OBSERVATIONS IN THE NORTH METRO HAVEN`T TURNED
OVER TO SOUTH YET...BUT SHOULD BE CLOSE TO DOING SO.
TORNADOES...HAIL...AND WIND IS POSSIBLE ANYWHERE IN THE WARM
SECTOR AND JUST NORTH OF THE BOUNDARY WHERE LOW LEVEL HELICITY
WILL BE ENHANCED. WE ALREADY HAVE CONVECTIVE INITIATION IN SW MN
AND IA...AND THIS POTENT WAVE WILL HAVE NO TROUBLE DRIVING STORMS
ACROSS THE AREA.
SHEAR IS VERY STRONG PER AREA VWPS AND FORECAST SOUNDINGS. 0-6KM
SHEAR IS MORE THAN SUFFICIENT FOR SUPERCELLS AND 0-1KM SHEAR OF
25-30KTS SUPPORTED BY RUC ANALYSIS AND MPX 18Z SOUNDING. THESE
SOURCES ALSO SUGGEST LITTLE CIN AND AND LOW LCL TO GO ALONG WITH
1000-2000 J/KG OF SURFACE CAPE. THESE ARE STRONG INDICATORS OF
TORNADOGENESIS AND EVEN THE POTENTIAL FOR STRONG TORNADOES GIVEN
THE STRONG SHEAR PROFILE IF SUPERCELLS CAN REMAIN DISCRETE. SUPERCELLS
WILL BE LIKELY WITH TORNADOES POSSIBLE. STORMS THAT FORM AND RIDE
ALONG THE WARM FRONT MAY PRODUCE TORNADOES AND ALSO SWATHS OF
DAMAGING WINDS. TORNADO THREAT DIMINISH GREATER THAN 30KM OR SO
NORTH OF THE WARM FRONT...WHERE STORMS SHOULD BECOME ELEVATED.
THERE WILL STILL BE A HAIL THREAT WITH THE STORMS THAT RIDE NORTH
OF THE WARM FRONT THIS EVENING. AGAIN...TORNADOES ARE POSSIBLE
RIGHT ALONG THE WARM FRONT...INCLUDING THE TWIN CITIES METRO.
LATE TONIGHT...THE COLD FRONT PASSES THROUGH AND 850MB
TEMPERATURES COLLAPSE FROM NORTHWEST TO SOUTHEAST BY MONDAY
MORNING. FORECAST PROFILES AND 1000-850MB LAYER WET BULB ARE COLD
ENOUGH TO SUPPORT SNOW EARLY MONDAY MORNING IN WESTERN AND
PORTIONS OF CENTRAL MN...EVEN INTO NORTHWEST WI. THE QUESTION IS
WHETHER THE THERMAL PROFILE GETS COLD ENOUGH BEFORE THE PRECIP
ENDS. WE THINK IT WILL...BUT ONLY ENOUGH FOR AN INCH OR AT THE
MOST A COUPLE INCHES NEAR AND NORTH OF A LINE FROM ALEXANDRIA TO
LITTLE FALLS TO RICE LAKE WI. A FEW INCHES IS POSSIBLE IN NORTHERN
MN.
IN THE EXTENDED...ZONAL FLOW ACROSS THE LOWER CONUS TRANSITIONS IN
MOST GUIDANCE TO A MORE AMPLIFIED FLOW PATTERN BY NEXT WEEKEND AS
MID-UPPER LEVEL TROUGHING JUST OFF THE WEST COAST DIGS
SOUTHWARD. RIDGING OVER THE WESTERN US AND A DOWNSTREAM TROUGH TO
THE EASTERN US. MODELS AND ENSEMBLES HAVE EMBEDDED IMPULSE
DISAGREEMENT INTO WED/THU...BUT FORECAST SPREAD AND UNCERTAINTY
INCREASE MORE FRI-SUN. WENT HIGHER POPS LATE IN THE FOR THAT NEXT
IMPULSE...WITH THUNDER CHANCES TO GO ALONG WITH THE POPS. RECENT
GFS AND PARALLEL GFS RUNS OFFER MORE AMPLIFIED MID-LATITUDE
FLOW...BUT AS THE ECMWF AND OTHER MODELS OFFER POOR RUN TO RUN
CONTINUITY WITH EMBEDDED SYSTEMS HARD TO ADD TO MUCH CONFIDENCE TO
THE EXTENDED. HPC SOLUTION REFLECTS A BLEND OF GFS/NAEFS/ECMWF
ENSEMBLE MEANS AS WELL.
&&
.AVIATION.../00Z TAF ISSUANCE/
VERY VIGOROUS SYSTEM WITH STRONG DYNAMICS...BUT THUS FAR STORMS
APPEAR TO BE MOVING TOO FAST TO BE DEEPLY ROOTED. PRESENTLY MAIN
LINE OF MARGINALLY SVR STORMS IS IN A N-S LINE FROM NEAR CBG TO MSP
THEN TRAILING TO ARND AEL. THESE STORMS HAVE BEEN LIFTING NE AT 40
TO 45 KTS. DRY AIR HAS PUNCHED VRY RPDLY ACROSS IOWA WITH SFC DWPTS
ALREADY IN THE 30S AND 40S AS FAR EAST AS MCW AND DSM. STILL SOME
THEAT FOR TSTMS IN MSP/STC FOR ANOTHER HOUR OR TWO WITH UPPER VORTEX
NOW NEARLY SW MN AND LIFTING RPDLY NE. THREAT WILL LINGER AT EAU
UNTIL AROUND 04Z. SFC LOW HAS BEEN BECOMING MORE ELONGATED WITH
SECONDARY CENTER NEAR MSP AND MAINLY LOW IN NW IA. SURFACE PRESSURE
GRADIENT HAS BEEN TIGHTENING NW OF LOW AND STRONG NELY WINDS WILL BE
AFFECTING ALL TAF SITES AFT 06Z. NE WINDS WILL SWEEP MVFR CIGS BACK
ACROSS ALL TAFS IN THE OVERNIGHT WITH IMPRVG CONDITONS MONDAY MRNG.
KMSP...THREAT FOR SVR TSTMS HAS MOVED E OF MSP...BUT WITH UPPER
VORTEX STILL TO OUR SW AND SFC BOUNDARY PRESENT...COULD STILL SEE A
CHC OF TSTMS TIL PERHAPS 02Z. SFC WIND DIRCTION PROBLEMATIC FOR
NEXT COUPLE HOURS WITH BOUNDARY IN VCNTY....BUT LINE OF TSTMS HAS
BROUGHT WINDS TO THE NW AND THEY SHUD NOW REMAIN WITH A NLY
COMPONENT. INCRSG N WINDS SHUD KEEP MVFR CIGS AT MSP THRU THE
OVERNITE.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR BLUE EARTH-
FARIBAULT-FREEBORN-MARTIN-STEELE-WASECA-WATONWAN.
WIND ADVISORY FROM 1 AM TO 7 AM CDT MONDAY FOR BLUE EARTH-BROWN-
FARIBAULT-FREEBORN-MARTIN-NICOLLET-STEELE-WASECA-WATONWAN.
WIND ADVISORY FROM 7 PM THIS EVENING TO 7 AM CDT MONDAY FOR
CHIPPEWA-DOUGLAS-KANDIYOHI-LAC QUI PARLE-POPE-REDWOOD-
RENVILLE-STEVENS-SWIFT-YELLOW MEDICINE.
WI...NONE.
&&
$$
CLF/BAP
AREA FORECAST DISCUSSION...UPDATED
NWS TWIN CITIES/CHANHASSEN MN
221 PM CDT SAT APR 14 2012
.UPDATE...
UPDATED FOR THE 18Z AVIATION DISCUSSION BELOW...
.DISCUSSION...
FORECAST CONCERN REMAINS SEVERE WEATHER THREAT LATER TONIGHT OVER
MAINLY SOUTHERN CWA AND EASTERN AREAS FOR SUNDAY. INITIALLY HAVE
SOME STRATUS LIFTING NORTH AND EAST OVER THE EASTERN CWA...IN THE
WAKE OF THE STRONG SHORT WAVE TROUGH THAT LIFTED THROUGH THE AREA
LAST EVENING. HRRR HAS THIS LIFTING AS FAR NORTH AS THE TWIN
CITIES AREA AND OVER WESTERN WISCONSIN...BURNING OFF THROUGH LATE
MORNING. WILL FOLLOW THIS TREND. SHOULD SEE FAIRLY NICE DAY WITH
INCREASING CLOUDS LATER IN THE AFTERNOON...AHEAD OF NEXT WEATHER
SYSTEM. WILL TRIM POPS BACK TO SMALL CHANCE SOUTHWEST AFTER 21Z
THIS AFTERNOON. MORE LIKELY MOVING IN DURING THE EVENING THOUGH.
WITH PLENTY OF SUNSHINE SHOULD SEE TEMPERATURES WARM THROUGH THE
60S TO SOME MID 70S POSSIBLE IN SOUTH CENTRAL MN.
STRONG WAVE LIFTS NORTHEAST OVER THE CWA OVERNIGHT TONIGHT WITH
ATTENDANT INCREASE IN INSTABILITY AND WIND SHEAR. POWERFUL JET
SEGMENT NOSES INTO THE AREA BY 06Z AND SURFACE WARM FRONT LIFTS
NORTH INTO THE AREA. SHOULD SEE SOME SEVERE WEATHER THREAT WORK
INTO SOUTHWEST MN DURING THE EVENING AS ACTIVITY OVER EASTERN
NEBRASKA/WESTERN IOWA LIFTS NORTH INTO THE AREA. ACTIVITY SHOULD
BECOME MORE ELEVATED WITH TIME AS IT LIFTS NORTH...WITH SOME HAIL
A THREAT LATER TONIGHT. ELEVATED NATURE OF ACTIVITY SHOULD LIMIT
TORNADO THREAT DURING THE NIGHT.
SYSTEM SLOW TO MOVE OUT AND ALL MODELS TRENDING SURFACE
LOW/OCCLUSION MOVING SLOWLY EAST INTO EASTERN MN/WESTERN WI BORDER
THROUGH 18Z-21Z SUNDAY. SHOULD SEE MAIN ACTIVITY LIFT INTO
CENTRAL MN EARLY SUNDAY WITH RAPID DEVELOPMENT EXPECTED AGAIN
TOWARD 18Z SUN WITH THE GFS SHOWING MAIN TROUGH AND 130 KNOT JET
NOSING LEADING TROUGH MOVING INTO WESTERN WISCONSIN. THIS AREA
WILL HAVE TO BE MONITORED FOR POSSIBLE SURFACE BASED DEVELOPMENT
IN THE EARLY AFTERNOON...WITH HAIL AND WIND A THREAT. SREF
CONTINUES TO POINT TO DEVELOPMENT A BIT FARTHER EAST...AND WITH
THE UNCERTAINTY INVOLVED...WONT INCLUDE SEVERE WORDING YET IN THE
EASTERN CWA.
COLD AIR MOVES IN FAIRLY RAPIDLY ON THE BACKSIDE OF THE TROUGH
SUNDAY NIGHT INTO MONDAY. CRITICAL THICKNESS VALUES INDICATE AT
LEAST A RAIN/SNOW MIX OVER MUCH OF THE CWA INTO MONDAY. MAY SEE
SOME LIGHT ACCUMULATION ON GRASSY AREAS LATER SUNDAY NIGHT/MONDAY
MORNING INTO CENTRAL AREAS.
LONGER TERM INDICATING MORE UNSETTLED PATTERN TO REMAIN OVER THE
AREA. SEVERAL CHANCES OF SHOWERS MOVING OVER THE AREA THROUGH THE
WEEK AND INTO THE WEEKEND AS FASTER/MORE ZONAL FLOW DEVELOPS.
TEMPERATURES SHOULD RANGE CLOSE TO OR SLIGHTLY BELOW NORMAL THROUGH
THE WEEK.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
.AVIATION.../18Z TAF ISSUANCE/
WEATHER BECOMES MORE ACTIVE WITH WIDESPREAD SHOWERS AND
THUNDERSTORMS AFTER 03Z TONIGHT. TRIED TO TIME IN 2 PERIODS OF
SHOWERS AND STORMS IN THE TAF...THE FIRST BEING THE THUNDER
CHANCES WHEN THE WARM FRONT ARRIVES BETWEEN 03-07Z TONIGHT. BRIEF
IFR VIS WHEN THUNDERSTORMS MOVE OVERHEAD WITH MODERATE/HEAVY
RAIN...AND WIDESPREAD MVFR CEILINGS WITH EMBEDDED IFR CEILINGS.
WORST OF THE THUNDERSTORMS SHIFT INTO EASTERN MN AND WESTERN WI BY
SUNDAY AFTERNOON. SOME OF THESE STORMS WILL CONTAIN HAIL. LOOK FOR
A PRONOUNCED WIND SHIFT TO THE SOUTH-SOUTHEAST AFTER THE WARM
FRONT PASSES THROUGH TONIGHT...AND STRONG SOUTHERLY WINDS
TOMORROW.
KMSP...BEST TIMING FOR THUNDER TONIGHT WILL BE BETWEEN 05/06Z
TONIGHT AND 09Z TONIGHT. SHOULD BE BREAK AND THEN ANOTHER ROUND
EARLY IN THE AFTERNOON TOMORROW. HIGHLIGHTED THE EARLY ROUND WITH
A LITTLE MORE DETAIL AND LATER TAFS WILL HAVE TO MONITOR THE
THUNDERSTORM POTENTIAL TOMORROW. MVFR CEILINGS ARE LIKELY THROUGH
THE TAF.
.SUN...IFR/MVFR CIGS/VSBYS -SHRA/TSRA.
.MON...LINGERING IFR/MVFR EARLY...THEN VFR MON AFTN. SNOW POSSIBLE
MONDAY MORNING.
.TUE...VFR.
.WED...VFR.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
DWE/CLF
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
627 AM CDT SAT APR 14 2012
.UPDATE...
.AVIATION.../12Z TAF ISSUANCE/
WAVE FROM LAST NIGHT HAS BROUGHT IN DRIER AIR BUT IFR CIGS TO OUR
SOUTHEAST WERE WORKING SLOWLY BACK TO THE NORTHWEST ON LIGHT
SOUTH BREEZES. SOME OF THE IFR CIGS WILL AFFECT KEAU AND KRNH FOR
A COUPLE HOURS THIS MORNING WHILE VSBYS AROUND 4-5SM MAY AFFECT
KMSP..KRWF...AND KSTC ALONG WITH FEW-SCT IFR LEVEL CLOUDS.
OTHERWISE VFR CONDITIONS INTO THE FIRST PART OF THE NIGHT.
HOWEVER...THE STRONG STORM SYSTEM TO OUR SOUTHWEST WILL BE PUSHING
NORTHEAST LATER TODAY. EXPECT SHOWERS TO MOVE INTO SOUTHWEST
MINNESOTA BY EVENING AND THEN OVER THE ENTIRE AREA BY MIDNIGHT. ALSO
EXPECT WIDESPREAD THUNDERSTORMS...ESPECIALLY SOUTH OF KSTC TO
KAXN..MAINLY AFTER MIDNIGHT...BUT A FEW STORMS WILL AFFECT THOSE
KRWF AND KSTC AS WELL. THE RISK OF STRONG STORMS WILL BE NEAR
KRWF WHERE HAIL IS POSSIBLE AND VSBYS DOWN TO 2SM IN HEAVIER RAIN
AS WELL. FOR OTHER SITES...MVFR VSBYS AND CIGS LIKELY IN STORMS.
WILL NEED TO WATCH FOR THE POSSIBILITY OF IFR CIGS NEAR KRWF AND
KMSP IN THE MORNING BUT HAVE JUST ABOVE THAT FOR NOW. SOUTHWEST
WINDS AROUND 10 KNOTS THEN BECOMING EAST TO SOUTHEAST ALL SITES BY
EVENING AND OVERNIGHT.
KMSP...CHANCE OF MVFR VSBYS AND A SCT LAYER OF IFR LEVEL CLOUDS
THIS MORNING...BUT MAY REMAIN JUST TO THE SOUTHEAST. OTHERWISE VFR
CONDITIONS INTO THE EARLY PART OF THE NIGHT. THE RISK OF
THUNDERSTORMS INCREASES BY MIDNIGHT WITH MVFR CONDITIONS. CURRENT
THINKING IS THAT ACTIVITY WILL MOVE FAIRLY FAST...AND MUCH OF THE
THUNDERSTORMS WILL HAVE MOVED TO THE EAST AND NORTH BY 12Z. WILL
HOLD OFF ON A STRONGER THUNDERSTORM MENTION WITH HAIL FOR
NOW...BUT SOMEHTING THAT MAY NEED TO BE CONSIDERED LATE. STILL
SOME MVFR CIGS WITH SCT SHOWERS AND AN ISOLATED STORM AFTER 12Z.
SOUTHWEST WINDS LESS THAN 10 KNOTS TODAY...THEN BECOMING EAST
TONIGHT WITH PERHAPS A FEW GUSTS. WINDS BECOMING MORE SOUTH ON
SUNDAY MORNING.
OUTLOOK...
.SUN...IFR/MVFR CIGS/VSBYS -SHRA/TSRA.
.MON...LINGERING IFR/MVFR EARLY...THEN VFR MON AFTN.
.TUE...VFR.
.WED...VFR.
&&
.DISCUSSION...
FORECAST CONCERN REMAINS SEVERE WEATHER THREAT LATER TONIGHT OVER
MAINLY SOUTHERN CWA AND EASTERN AREAS FOR SUNDAY. INITIALLY HAVE
SOME STRATUS LIFTING NORTH AND EAST OVER THE EASTERN CWA...IN THE
WAKE OF THE STRONG SHORT WAVE TROUGH THAT LIFTED THROUGH THE AREA
LAST EVENING. HRRR HAS THIS LIFTING AS FAR NORTH AS THE TWIN
CITIES AREA AND OVER WESTERN WISCONSIN...BURNING OFF THROUGH LATE
MORNING. WILL FOLLOW THIS TREND. SHOULD SEE FAIRLY NICE DAY WITH
INCREASING CLOUDS LATER IN THE AFTERNOON...AHEAD OF NEXT WEATHER
SYSTEM. WILL TRIM POPS BACK TO SMALL CHANCE SOUTHWEST AFTER 21Z
THIS AFTERNOON. MORE LIKELY MOVING IN DURING THE EVENING THOUGH.
WITH PLENTY OF SUNSHINE SHOULD SEE TEMPERATURES WARM THROUGH THE
60S TO SOME MID 70S POSSIBLE IN SOUTH CENTRAL MN.
STRONG WAVE LIFTS NORTHEAST OVER THE CWA OVERNIGHT TONIGHT WITH
ATTENDANT INCREASE IN INSTABILITY AND WIND SHEAR. POWERFUL JET
SEGMENT NOSES INTO THE AREA BY 06Z AND SURFACE WARM FRONT LIFTS
NORTH INTO THE AREA. SHOULD SEE SOME SEVERE WEATHER THREAT WORK
INTO SOUTHWEST MN DURING THE EVENING AS ACTIVITY OVER EASTERN
NEBRASKA/WESTERN IOWA LIFTS NORTH INTO THE AREA. ACTIVITY SHOULD
BECOME MORE ELEVATED WITH TIME AS IT LIFTS NORTH...WITH SOME HAIL
A THREAT LATER TONIGHT. ELEVATED NATURE OF ACTIVITY SHOULD LIMIT
TORNADO THREAT DURING THE NIGHT.
SYSTEM SLOW TO MOVE OUT AND ALL MODELS TRENDING SURFACE
LOW/OCCLUSION MOVING SLOWLY EAST INTO EASTERN MN/WESTERN WI BORDER
THROUGH 18Z-21Z SUNDAY. SHOULD SEE MAIN ACTIVITY LIFT INTO
CENTRAL MN EARLY SUNDAY WITH RAPID DEVELOPMENT EXPECTED AGAIN
TOWARD 18Z SUN WITH THE GFS SHOWING MAIN TROUGH AND 130 KNOT JET
NOSING LEADING TROUGH MOVING INTO WESTERN WISCONSIN. THIS AREA
WILL HAVE TO BE MONITORED FOR POSSIBLE SURFACE BASED DEVELOPMENT
IN THE EARLY AFTERNOON...WITH HAIL AND WIND A THREAT. SREF
CONTINUES TO POINT TO DEVELOPMENT A BIT FARTHER EAST...AND WITH
THE UNCERTAINTY INVOLVED...WONT INCLUDE SEVERE WORDING YET IN THE
EASTERN CWA.
COLD AIR MOVES IN FAIRLY RAPIDLY ON THE BACKSIDE OF THE TROUGH
SUNDAY NIGHT INTO MONDAY. CRITICAL THICKNESS VALUES INDICATE AT
LEAST A RAIN/SNOW MIX OVER MUCH OF THE CWA INTO MONDAY. MAY SEE
SOME LIGHT ACCUMULATION ON GRASSY AREAS LATER SUNDAY NIGHT/MONDAY
MORNING INTO CENTRAL AREAS.
LONGER TERM INDICATING MORE UNSETTLED PATTERN TO REMAIN OVER THE
AREA. SEVERAL CHANCES OF SHOWERS MOVING OVER THE AREA THROUGH THE
WEEK AND INTO THE WEEKEND AS FASTER/MORE ZONAL FLOW DEVELOPS.
TEMPERATURES SHOULD RANGE CLOSE TO OR SLIGHTLY BELOW NORMAL THROUGH
THE WEEK.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
DWE/JPR
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
403 AM CDT SAT APR 14 2012
.DISCUSSION...
FORECAST CONCERN REMAINS SEVERE WEATHER THREAT LATER TONIGHT OVER
MAINLY SOUTHERN CWA AND EASTERN AREAS FOR SUNDAY. INITIALLY HAVE
SOME STRATUS LIFTING NORTH AND EAST OVER THE EASTERN CWA...IN THE
WAKE OF THE STRONG SHORT WAVE TROUGH THAT LIFTED THROUGH THE AREA
LAST EVENING. HRRR HAS THIS LIFTING AS FAR NORTH AS THE TWIN
CITIES AREA AND OVER WESTERN WISCONSIN...BURNING OFF THROUGH LATE
MORNING. WILL FOLLOW THIS TREND. SHOULD SEE FAIRLY NICE DAY WITH
INCREASING CLOUDS LATER IN THE AFTERNOON...AHEAD OF NEXT WEATHER
SYSTEM. WILL TRIM POPS BACK TO SMALL CHANCE SOUTHWEST AFTER 21Z
THIS AFTERNOON. MORE LIKELY MOVING IN DURING THE EVENING THOUGH.
WITH PLENTY OF SUNSHINE SHOULD SEE TEMPERATURES WARM THROUGH THE
60S TO SOME MID 70S POSSIBLE IN SOUTH CENTRAL MN.
STRONG WAVE LIFTS NORTHEAST OVER THE CWA OVERNIGHT TONIGHT WITH
ATTENDANT INCREASE IN INSTABILITY AND WIND SHEAR. POWERFUL JET
SEGMENT NOSES INTO THE AREA BY 06Z AND SURFACE WARM FRONT LIFTS
NORTH INTO THE AREA. SHOULD SEE SOME SEVERE WEATHER THREAT WORK
INTO SOUTHWEST MN DURING THE EVENING AS ACTIVITY OVER EASTERN
NEBRASKA/WESTERN IOWA LIFTS NORTH INTO THE AREA. ACTIVITY SHOULD
BECOME MORE ELEVATED WITH TIME AS IT LIFTS NORTH...WITH SOME HAIL
A THREAT LATER TONIGHT. ELEVATED NATURE OF ACTIVITY SHOULD LIMIT
TORNADO THREAT DURING THE NIGHT.
SYSTEM SLOW TO MOVE OUT AND ALL MODELS TRENDING SURFACE
LOW/OCCLUSION MOVING SLOWLY EAST INTO EASTERN MN/WESTERN WI BORDER
THROUGH 18Z-21Z SUNDAY. SHOULD SEE MAIN ACTIVITY LIFT INTO
CENTRAL MN EARLY SUNDAY WITH RAPID DEVELOPMENT EXPECTED AGAIN
TOWARD 18Z SUN WITH THE GFS SHOWING MAIN TROUGH AND 130 KNOT JET
NOSING LEADING TROUGH MOVING INTO WESTERN WISCONSIN. THIS AREA
WILL HAVE TO BE MONITORED FOR POSSIBLE SURFACE BASED DEVELOPMENT
IN THE EARLY AFTERNOON...WITH HAIL AND WIND A THREAT. SREF
CONTINUES TO POINT TO DEVELOPMENT A BIT FARTHER EAST...AND WITH
THE UNCERTAINTY INVOLVED...WONT INCLUDE SEVERE WORDING YET IN THE
EASTERN CWA.
COLD AIR MOVES IN FAIRLY RAPIDLY ON THE BACKSIDE OF THE TROUGH
SUNDAY NIGHT INTO MONDAY. CRITICAL THICKNESS VALUES INDICATE AT
LEAST A RAIN/SNOW MIX OVER MUCH OF THE CWA INTO MONDAY. MAY SEE
SOME LIGHT ACCUMULATION ON GRASSY AREAS LATER SUNDAY NIGHT/MONDAY
MORNING INTO CENTRAL AREAS.
LONGER TERM INDICATING MORE UNSETTLED PATTERN TO REMAIN OVER THE
AREA. SEVERAL CHANCES OF SHOWERS MOVING OVER THE AREA THROUGH THE
WEEK AND INTO THE WEEKEND AS FASTER/MORE ZONAL FLOW DEVELOPS.
TEMPERATURES SHOULD RANGE CLOSE TO OR SLIGHTLY BELOW NORMAL THROUGH
THE WEEK.
&&
.AVIATION.../06Z TAF ISSUANCE/
SHORT TERM CONCERNS TONIGHT THROUGH SATURDAY MORNING...ARE LOW
CEILINGS AND VISIBILITIES. STRATUS HAD EXPANDED OVER CENTRAL MN INTO
WESTERN WISCONSIN...AHEAD OF THE SURFACE TROUGH/SHORTWAVE TROUGH.
EXPECT IFR/LIFR CONDITIONS TO PREVAIL OVER PORTIONS OF SOUTH CENTRAL
AND WESTERN WISCONSIN THROUGH MID MORNING. THE BACK EDGE OF THE
CLOUDS EXTENDS FROM KAQP TO NEAR KSPW(SPENCER IOWA). CONDITIONS WILL
SLOWLY IMPROVE TO VFR OVER WEST CENTRAL MN OVERNIGHT...AND OVER
PARTS OF SOUTH CENTRAL AND EASTERN MN LATE SATURDAY MORNING.
THE OTHER CONCERNS ARE THUNDERSTORM CHANCES AND RISK OF SEVERE
STORMS LATE SATURDAY EVENING/SATURDAY NIGHT AND SUNDAY. A WARM FRONT
WILL BEGIN TO LIFT NORTHEAST OVER THE FORECAST AREA DURING THE
PERIOD. MEANWHILE...A SURFACE LOW PRESSURE SYSTEM WILL ALSO
STRENGTHEN OVER THE CENTRAL PLAINS...AS STRONG UPPER LEVEL JET
PUNCHING NORTHWARD INTO THE UPPER MIDWEST SATURDAY NIGHT. EXPECT
THUNDERSTORMS TO BREAKOUT IN THE WARM SECTOR OVER IOWA/NEBRASKA
SATURDAY EVENING AND TREK NORTHEAST OVER MN TOMMORROW NIGHT. WEATHER
CONDITIONS EXPECTED TO LOWER TO MVFR/IFR FLIGHT CATEGORY IN
THUNDERSTORMS.
MSP...EXPECT WIDESPREAD IFR/LIFR CONDITIONS OVERNIGHT...WITH
CONDITIONS SLOWLY IMPROVING TO VFR BY LATE SATURDAY MORNING.
THUNDERSTORMS DEVELOPING LATE SATURDAY EVENING/OVERNIGHT. ISOLD
SEVERE STORMS POSSIBLE...MAINLY LARGE HAIL AND DAMAGING WINDS...ARE
THE MAIN THREAT.
.SUN...IFR/MVFR CIGS/VSBYS -SHRA/TSRA.
.MON...LINGERING IFR/MVFR EARLY...THEN VFR MON AFTN.
.TUE...VFR.
.WED...VFR.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
DWE/JPR
AREA FORECAST DISCUSSION
NWS JACKSON MS
1000 PM CDT SUN APR 15 2012
.DISCUSSION...MADE SOME SMALL ADJUSTMENTS TO THE POPS AND TEMPS TO
ACCOUNT FOR THE LATEST MODELS AND THE MOVEMENT OF THE LINE. RAISED
HOURLY VALUES AND OVERNIGHT LOWS A DEGREE OR TWO. SOUTHERLY WINDS
CONTINUE TO GUST ACROSS THE REGION AND THE BOUNDARY IS MOVING
RELATIVELY SLOWLY. DEWPOINTS WILL LIKELY REMAIN THE LOWER TO MID 60S
FOR MOST OF THE NIGHT...ESPECIALLY FOR THE EASTERN HALF OF THE AREA.
ADJUSTED THE POPS TO SLOW THE RAIN MOVING INTO AREA BY A FEW HOURS.
RAIN IS STILL WEST OF THE REGION...BUT SHOULD BE IN THE SOUTHEAST
ARKANSAS COUNTIES BEFORE MIDNIGHT. LOOKS LIKE MUCH OF THE NORTHWEST/WEST
ZONES WILL GET RAIN TONIGHT. LEFT THE BEST CHANCES WEST OF INTERSTATE
55 THROUGH 12Z. ALTHOUGH AIR ACROSS THE CWA HAS BEEN STABLE...CAP WAS
NOT THAT STRONG...MODEL SOUNDINGS SHOW IT DISAPPEARING. THE RUC SHOWS
A PRE-FRONTAL TROUGH MOVING INTO THE CWA...SPEED SHEAR WILL CONTINUE
ACROSS THE AREA...SO INCREASED THUNDER ACROSS THE AREA AFTER
MIDNIGHT. LEFT UNCERTAINTY IN THE NORTHWEST SINCE THE AREA SHOULD BE
BEHIND THE BOUNDARY TOWARD EARLY MORNING AND THUNDERSTORMS WILL BE
LESS. OTHERWISE...THE FORECAST WAS GOOD.
&&
.AVIATION...SLY WINDS 10-20 MPH WITH HIGHER GUSTS WILL CONTINUE TO
GRADUALLY DECREASE. OVERNIGHT...TIMING OF A LINE OF SHRA/TSRA WILL
BE THE FOCUS. LOOK FOR IFR/MVFR CEILINGS TO DEVELOP OVER MUCH OF THE
REGION TONIGHT WITH CEILINGS STARTING TO LOWER BY 06Z. LOCAL MVFR
VSBY IN FOG WILL BE POSSIBLE BUT VSBY WILL GENERALLY REMAIN VFR AT OR
ABOVE 6SM. LOCAL MVFR VSBY WILL ALSO BE POSSIBLE IN POCKETS OF
HEAVIER PRECIP. 03
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 68 80 60 76 / 42 69 62 39
MERIDIAN 66 81 61 75 / 6 61 70 59
VICKSBURG 66 81 58 78 / 75 67 48 37
HATTIESBURG 67 85 64 77 / 2 79 70 61
NATCHEZ 68 80 61 76 / 76 71 63 47
GREENVILLE 65 79 57 77 / 99 31 25 12
GREENWOOD 67 80 58 76 / 76 58 36 21
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
07/03
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1245 PM CDT SAT APR 14 2012
...UPDATED AVIATION DISCUSSION...
.DISCUSSION...
Short Range (Today through Monday)...
A large trough continues to make landfall over the west coast with a
100+ knot jet streak helping dig it towards the Four Corners. It is
this primary trough that will be our focus for Saturday`s into
Sunday`s weather as it begins to lift through the Plains States.
Closer to home, a compact shortwave is noted lifting through the
northern Plains into Canada ahead of the main trough to the west,
with a weakly defined frontal boundary stretching southwest from it
in Minnesota through Iowa and eastern Kansas. Frontal boundary is
only notable this morning as it helps define the location of the warm
sector -where all the thunderstorm activity is- and the cold sector
-where the storms are not-. Ongoing thunderstorm activity in the warm
sector, currently stretched from central Oklahoma northeast through
Missouri into central Illinois, appears to owe its existence to the
moisture and warm air advection resulting from the persistent
southwest low level jet.
Previous days runs of the NMM-WRF and even the NSSL-WRF have done a
fine job with the handling of convection across our region of the
Plains, but recent 00Z from the 14th appeared to have some
initialization problems, and therefore don`t even have the current
activity this morning handled well. Conversely, the 01Z HRRR has
done a decent job of initializing overnight, and capturing trends
noted thus far this morning. NAM, and to a lesser extent the GFS,
both agree well with the HRRR through the periods that they overlap,
so a combination of these model runs have been used to guide today`s
forecast.
For today...thunderstorms will be ongoing this morning as the low
level jet continues to feed the needed ingredients for thunderstorms
across the region. Models have been hinting at, and latest radar
trends would agree, that the jet will become a little less focused
as we transit the sunrise hours, resulting in a broad warm air wing
of showers and thunderstorms developing from the current activity
across Oklahoma and Kansas. This activity would shift north through
the morning hours, likely residing in Nebraska and Iowa by this
afternoon. Have gone with likely POPs through the morning hours as a
result, while limiting POPs after noon to the chance category across
the northern half of the forecast region. Behind the warm wing of
convective activity a weak, but still present, EML should help cap
off new activity during the afternoon hours. So, what chance POPs
are in for the afternoon are more for lingering activity behind the
warm wing.
As we move towards tonight, attention for a significant round of
severe weather remains focused in areas just to the west, from
central Oklahoma north into the eastern half of Nebraska. As the
100+ knot jet streak rounding the base of the western CONUS trough
shifting through the Plains later tonight, it will bring a favorable
diffluent flow aloft to the dry-line across Kansas and Oklahoma this
evening, and while the instability from diurnal heating will be
fading some, there should be more than enough lingering to fuel all
manner of severe weather. Latest model runs continue to keep the
focus for the onset time of these KS-OK initiating storms after 00Z.
With growing confidence in the late onset of storms, have restricted
the likely POPs for the evening hours to areas west of Interstate-35,
after 03Z, as current initiation timing indicates that it might be
near, or after, midnight before storms shift into our region. All
modes of severe weather still look possible with tonight`s storms
given the abundant shear and helicity values, meaning large hail,
damaging winds, flooding rains, and isolated tornadoes will be
possible with any of tonight`s storms. However, the highest potential
for any of the severe weather looks to be roughly along the Kansas-
Missouri border and points along and west of Interstate-35, and is
where the risk of severe thunderstorms has been highlighted in the
forecast.
Sunday...storms may be ongoing in the morning hours again. Currently
trends indicate that left over activity from the overnight hours may
linger across Missouri through part of the daylight hours, though it
looks more likely that any left over storms will be cast off showers
from a more linear convective system moving from eastern Oklahoma
into Arkansas and southern Missouri as the cold front advances
across the Plains. Have continued to highlighting the thunderstorm
potential Sunday morning with likely POPs across the eastern side of
the forecast area, but have worked to quickly remove the POPs
starting in the afternoon. Otherwise, it will be windy ahead of and
behind the cold front shifting across Kansas and Missouri. It`s
likely that subsidence behind the front will produce enough clearing
of the skies to allow for deep layer mixing, which model soundings
suggest could be through at least 800mb. With multiple models
advising 850mb wind speeds of 45 to 50 knots, thoughts are Sunday
will be windy, and will likely need a wind advisory for the
mid-morning through afternoon hours.
Cutter
Medium Range (Tuesday-Friday)...
A more quiet weather pattern is expected for next week as more of a
zonal flow sets up over the central U.S. For Tuesday, an area of
high pressure will be over the Great Lakes region, resulting in
light southerly winds into the region and temperatures near seasonal
normal. Models show a shortwave tracking eastward across the
Northern Plains Tuesday night and Wednesday. A few scattered showers
are possible across north central and northeast Missouri Wednesday
afternoon and evening as a cold front extending from the surface low
beneath the shortwave dips southward into the area. These showers
will clear out by Thursday morning as the shortwave progresses
eastward, however models are showing the frontal boundary becoming
stationary near the Missouri/Iowa border. For Thursday, with high
pressure over the southeastern U.S. and a second surface low just
east of the Rockies, southerly winds will help boost temperatures
above normal into the 70s. Depending upon where the stationary
boundary is located in the vicinity of the Missouri/Iowa border,
additional scattered showers and thunderstorms are possible Thursday
afternoon across extreme northern Missouri. Better chances for more
widespread precipitation look to be Thursday night and Friday as the
surface low and associated cold front progress eastward into the
region. Models show precipitation exiting east of the region by
Friday evening. These showers and thunderstorms will help to drop
temperatures a few degrees for Friday, but still looking at above
normal conditions.
ACH
&&
.AVIATION...
For the 18Z TAFs...Showers and thunderstorms that have developed
west of the terminals this afternoon will remain to the west
although STJ may have a few thunderstorm in the VC through 19Z.
Otherwise...models depict a second area of thunderstorms developing
across southern Kansas that may lift into the VC of the terminals
for late this afternoon/evening best chance on timing is between
22z-01z. A third chance for thunderstorms will come in the overnight
hours as a line of thunderstorms is forecast to move through the
terminals. Due to uncertainty of the timing of this line have
included VCTS at 09Z at the terminals. Winds will be out of the
south between 15-25kt with gusts between 20-30kt through the TAF
period.
73
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
WFO EAX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
635 AM CDT Sat Apr 14 2012
...UPDATED AVIATION DISCUSSION...
.DISCUSSION...
Short Range (Today through Monday)...
A large trough continues to make landfall over the west coast with a
100+ knot jet streak helping dig it towards the Four Corners. It is
this primary trough that will be our focus for Saturday`s into
Sunday`s weather as it begins to lift through the Plains States.
Closer to home, a compact shortwave is noted lifting through the
northern Plains into Canada ahead of the main trough to the west,
with a weakly defined frontal boundary stretching southwest from it
in Minnesota through Iowa and eastern Kansas. Frontal boundary is
only notable this morning as it helps define the location of the warm
sector -where all the thunderstorm activity is- and the cold sector
-where the storms are not-. Ongoing thunderstorm activity in the warm
sector, currently stretched from central Oklahoma northeast through
Missouri into central Illinois, appears to owe its existence to the
moisture and warm air advection resulting from the persistent
southwest low level jet.
Previous days runs of the NMM-WRF and even the NSSL-WRF have done a
fine job with the handling of convection across our region of the
Plains, but recent 00Z from the 14th appeared to have some
initialization problems, and therefore don`t even have the current
activity this morning handled well. Conversely, the 01Z HRRR has
done a decent job of initializing overnight, and capturing trends
noted thus far this morning. NAM, and to a lesser extent the GFS,
both agree well with the HRRR through the periods that they overlap,
so a combination of these model runs have been used to guide today`s
forecast.
For today...thunderstorms will be ongoing this morning as the low
level jet continues to feed the needed ingredients for thunderstorms
across the region. Models have been hinting at, and latest radar
trends would agree, that the jet will become a little less focused
as we transit the sunrise hours, resulting in a broad warm air wing
of showers and thunderstorms developing from the current activity
across Oklahoma and Kansas. This activity would shift north through
the morning hours, likely residing in Nebraska and Iowa by this
afternoon. Have gone with likely POPs through the morning hours as a
result, while limiting POPs after noon to the chance category across
the northern half of the forecast region. Behind the warm wing of
convective activity a weak, but still present, EML should help cap
off new activity during the afternoon hours. So, what chance POPs
are in for the afternoon are more for lingering activity behind the
warm wing.
As we move towards tonight, attention for a significant round of
severe weather remains focused in areas just to the west, from
central Oklahoma north into the eastern half of Nebraska. As the
100+ knot jet streak rounding the base of the western CONUS trough
shifting through the Plains later tonight, it will bring a favorable
diffluent flow aloft to the dry-line across Kansas and Oklahoma this
evening, and while the instability from diurnal heating will be
fading some, there should be more than enough lingering to fuel all
manner of severe weather. Latest model runs continue to keep the
focus for the onset time of these KS-OK initiating storms after 00Z.
With growing confidence in the late onset of storms, have restricted
the likely POPs for the evening hours to areas west of Interstate-35,
after 03Z, as current initiation timing indicates that it might be
near, or after, midnight before storms shift into our region. All
modes of severe weather still look possible with tonight`s storms
given the abundant shear and helicity values, meaning large hail,
damaging winds, flooding rains, and isolated tornadoes will be
possible with any of tonight`s storms. However, the highest potential
for any of the severe weather looks to be roughly along the Kansas-
Missouri border and points along and west of Interstate-35, and is
where the risk of severe thunderstorms has been highlighted in the
forecast.
Sunday...storms may be ongoing in the morning hours again. Currently
trends indicate that left over activity from the overnight hours may
linger across Missouri through part of the daylight hours, though it
looks more likely that any left over storms will be cast off showers
from a more linear convective system moving from eastern Oklahoma into
Arkansas and southern Missouri as the cold front advances across the
Plains. Have continued to highlighting the thunderstorm potential
Sunday morning with likely POPs across the eastern side of the
forecast area, but have worked to quickly remove the POPs starting in
the afternoon. Otherwise, it will be windy ahead of and behind the
cold front shifting across Kansas and Missouri. It`s likely that
subsidence behind the front will produce enough clearing of the skies
to allow for deep layer mixing, which model soundings suggest could
be through at least 800mb. With multiple models advising 850mb wind
speeds of 45 to 50 knots, thoughts are Sunday will be windy, and will
likely need a wind advisory for the mid-morning through afternoon
hours.
Cutter
Medium Range (Tuesday-Friday)...
A more quiet weather pattern is expected for next week as more of a
zonal flow sets up over the central U.S. For Tuesday, an area of
high pressure will be over the Great Lakes region, resulting in
light southerly winds into the region and temperatures near seasonal
normal. Models show a shortwave tracking eastward across the
Northern Plains Tuesday night and Wednesday. A few scattered showers
are possible across north central and northeast Missouri Wednesday
afternoon and evening as a cold front extending from the surface low
beneath the shortwave dips southward into the area. These showers
will clear out by Thursday morning as the shortwave progresses
eastward, however models are showing the frontal boundary becoming
stationary near the Missouri/Iowa border. For Thursday, with high
pressure over the southeastern U.S. and a second surface low just
east of the Rockies, southerly winds will help boost temperatures
above normal into the 70s. Depending upon where the stationary
boundary is located in the vicinity of the Missouri/Iowa border,
additional scattered showers and thunderstorms are possible Thursday
afternoon across extreme northern Missouri. Better chances for more
widespread precipitation look to be Thursday night and Friday as the
surface low and associated cold front progress eastward into the
region. Models show precipitation exiting east of the region by
Friday evening. These showers and thunderstorms will help to drop
temperatures a few degrees for Friday, but still looking at above
normal conditions.
ACH
&&
.AVIATION...
For the 12Z TAFs...Thunderstorms continue to percolate across areas
from southeast Kansas through northeast Missouri, with the activity
currently passing south of all the terminals. However, this might
change later in the morning as a broad area of thunderstorms may
develop and lift through western Missouri during the late morning to
early afternoon hours. Confidence in timing and/or placement of storms
with this is low, so have opted to characterize any possible late
morning activity with VCTS. Confidence is much higher that storms will
develop later tonight in Kansas, which will shift northeast through
the terminals during the late night hours. Otherwise, watch for gusty
south winds to begin prevailing today, with the strong and gusty
nature of the winds likely persisting through the entirety of, and
beyond, this TAF cycle.
Cutter
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
WFO EAX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
426 AM CDT Sat Apr 14 2012
.DISCUSSION...
Short Range (Today through Monday)...
A large trough continues to make landfall over the west coast with a
100+ knot jet streak helping dig it towards the Four Corners. It is
this primary trough that will be our focus for Saturday`s into
Sunday`s weather as it begins to lift through the Plains States.
Closer to home, a compact shortwave is noted lifting through the
northern Plains into Canada ahead of the main trough to the west,
with a weakly defined frontal boundary stretching southwest from it
in Minnesota through Iowa and eastern Kansas. Frontal boundary is
only notable this morning as it helps define the location of the warm
sector -where all the thunderstorm activity is- and the cold sector
-where the storms are not-. Ongoing thunderstorm activity in the warm
sector, currently stretched from central Oklahoma northeast through
Missouri into central Illinois, appears to owe its existence to the
moisture and warm air advection resulting from the persistent
southwest low level jet.
Previous days runs of the NMM-WRF and even the NSSL-WRF have done a
fine job with the handling of convection across our region of the
Plains, but recent 00Z from the 14th appeared to have some
initialization problems, and therefore don`t even have the current
activity this morning handled well. Conversely, the 01Z HRRR has
done a decent job of initializing overnight, and capturing trends
noted thus far this morning. NAM, and to a lesser extent the GFS,
both agree well with the HRRR through the periods that they overlap,
so a combination of these model runs have been used to guide today`s
forecast.
For today...thunderstorms will be ongoing this morning as the low
level jet continues to feed the needed ingredients for thunderstorms
across the region. Models have been hinting at, and latest radar
trends would agree, that the jet will become a little less focused
as we transit the sunrise hours, resulting in a broad warm air wing
of showers and thunderstorms developing from the current activity
across Oklahoma and Kansas. This activity would shift north through
the morning hours, likely residing in Nebraska and Iowa by this
afternoon. Have gone with likely POPs through the morning hours as a
result, while limiting POPs after noon to the chance category across
the northern half of the forecast region. Behind the warm wing of
convective activity a weak, but still present, EML should help cap
off new activity during the afternoon hours. So, what chance POPs
are in for the afternoon are more for lingering activity behind the
warm wing.
As we move towards tonight, attention for a significant round of
severe weather remains focused in areas just to the west, from
central Oklahoma north into the eastern half of Nebraska. As the
100+ knot jet streak rounding the base of the western CONUS trough
shifting through the Plains later tonight, it will bring a favorable
diffluent flow aloft to the dry-line across Kansas and Oklahoma this
evening, and while the instability from diurnal heating will be
fading some, there should be more than enough lingering to fuel all
manner of severe weather. Latest model runs continue to keep the
focus for the onset time of these KS-OK initiating storms after 00Z.
With growing confidence in the late onset of storms, have restricted
the likely POPs for the evening hours to areas west of Interstate-35,
after 03Z, as current initiation timing indicates that it might be
near, or after, midnight before storms shift into our region. All
modes of severe weather still look possible with tonight`s storms
given the abundant shear and helicity values, meaning large hail,
damaging winds, flooding rains, and isolated tornadoes will be
possible with any of tonight`s storms. However, the highest potential
for any of the severe weather looks to be roughly along the Kansas-
Missouri border and points along and west of Interstate-35, and is
where the risk of severe thunderstorms has been highlighted in the
forecast.
Sunday...storms may be ongoing in the morning hours again. Currently
trends indicate that left over activity from the overnight hours may
linger across Missouri through part of the daylight hours, though it
looks more likely that any left over storms will be cast off showers
from a more linear convective system moving from eastern Oklahoma into
Arkansas and southern Missouri as the cold front advances across the
Plains. Have continued to highlighting the thunderstorm potential
Sunday morning with likely POPs across the eastern side of the
forecast area, but have worked to quickly remove the POPs starting in
the afternoon. Otherwise, it will be windy ahead of and behind the
cold front shifting across Kansas and Missouri. It`s likely that
subsidence behind the front will produce enough clearing of the skies
to allow for deep layer mixing, which model soundings suggest could
be through at least 800mb. With multiple models advising 850mb wind
speeds of 45 to 50 knots, thoughts are Sunday will be windy, and will
likely need a wind advisory for the mid-morning through afternoon
hours.
Cutter
Medium Range (Tuesday-Friday)...
A more quiet weather pattern is expected for next week as more of a
zonal flow sets up over the central U.S. For Tuesday, an area of
high pressure will be over the Great Lakes region, resulting in
light southerly winds into the region and temperatures near seasonal
normal. Models show a shortwave tracking eastward across the
Northern Plains Tuesday night and Wednesday. A few scattered showers
are possible across north central and northeast Missouri Wednesday
afternoon and evening as a cold front extending from the surface low
beneath the shortwave dips southward into the area. These showers
will clear out by Thursday morning as the shortwave progresses
eastward, however models are showing the frontal boundary becoming
stationary near the Missouri/Iowa border. For Thursday, with high
pressure over the southeastern U.S. and a second surface low just
east of the Rockies, southerly winds will help boost temperatures
above normal into the 70s. Depending upon where the stationary
boundary is located in the vicinity of the Missouri/Iowa border,
additional scattered showers and thunderstorms are possible Thursday
afternoon across extreme northern Missouri. Better chances for more
widespread precipitation look to be Thursday night and Friday as the
surface low and associated cold front progress eastward into the
region. Models show precipitation exiting east of the region by
Friday evening. These showers and thunderstorms will help to drop
temperatures a few degrees for Friday, but still looking at above
normal conditions.
ACH
&&
.AVIATION...
The next batch of showers and thunderstorms now ongoing across parts
of southeast Kansas tonight. This activity is moving towards the
northeast, which should keep the bulk of the precipitation south of
the terminals. Cannot rule out some of this expanding into the KMKC
but confidence is too low to include at this time. Otherwise,
periodic sct low level clouds will traverse across the TAF sites over
the next few hours. MVFR cigs along with some light fog still remain
possible later tonight into the early morning hours as low level
moisture continues to advect northward. Scattered showers and
thunderstorms may blossom by the morning hours across eastern Kansas
and move across the terminals by the mid to late morning. Confidence
is not high at this time but will include VCTS at this time to
account. Otherwise, winds will strengthen through the day becoming
strong and gusty through the afternoon.
Deroche
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
WFO EAX
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1154 PM CDT Fri Apr 13 2012
...UPDATED AVIATION DISCUSSION...
.DISCUSSION...
Short Range (Tonight through Sunday)...
Surface trough extends from western IA through nw MO and through nw
OK. Boundary appears to have stalled and is delineated by cumulus
congestus on the northern portion and developing strong/possible
severe convection from southeastern KS swwd. This latter activity is
best handled by LSX local WRF while the 18z HRRR and 12z 4km NMM-WRF
models are a bit slower in their evolution. Airmass is moderately
unstable with MUCAPE in the 2000-2500 J/kg range with 40kt 0-6km
shear and 200 m2/s2 storm relative helicity, in essence enough to
support supercells. As the low level jet kicks in this evening
expect the growing area of convection to expand east-northeastward
along a pseudo warm front that the LSX local WRF extends across the
far southern counties. This boundary and the convection will be
supported by the increasing southerly low level jet and allow the
complex to spread north toward the MO River by Saturday morning.
Have used this idea to construct grids/zones for tonight. There will
be some severe potential for the far southern counties overnight
with large hail the primary severe threat. Heavy rains are possible
over the far southern counties but 3hr flash flood guidance
averaging 2.5 inches/3 hours suggests rainfall tonight not enough to
warrant a watch.
Activity will likely be ongoing across area south of the MO River.
The warm front and convection will continue northward during the day
and have scaled back afternoon pops south of the MO River.
Temperatures will be tricky due to the rain cooled airmass and cloud
cover. Should the sun fail to come out the current temperatures,
although cooler than the previous forecast, may prove to be still
too warm.
Severe risk during the daylight hours will be tied to the morning
convection and believe it will be quite low as the airmass will
likely be quite saturated and minimal instability. Main focus for
the severe risk will be Saturday late evening into Sunday morning.
Upstream severe weather outbreak will likely advance steadily
eastward as a squall line as individual cells race northeast off the
line in excess of 50kts. Despite weakening instability during the
evening hours the low level shear will be quite high and thus still
able to support rotating individual storms through the night. As a
result there will be a risk of severe weather mainly west of
Interstate 35 for Saturday night. All storm modes...large hail,
damaging winds and isolated tornadoes...will be possible.
Sunday`s severe threat will likely be held hostage by how Saturday
night`s convective event unfolds and lays out any boundaries. Will
use a model consensus approach which suggests best convective
chances will be over the eastern half of the CWA. Rain chances will
end from west to east during the day on Sunday with Sunday night
likely dry.
MJ
Medium Range (Monday through Friday)...
By Monday the upper level trough that made for a stormy weekend will
shift east of the area and flatten out as the upper level flow
across the CONUS becomes more zonal. The main weather concerns will
revolve around two chances for precipitation, the first on Wednesday
and again Friday. High pressure will move into the area on Monday
behind a departing cold front. Temperatures will range into the
upper 50s to lower 60s. The surface ridge will remain over the area
on Tuesday as abundant sunshine will help temperatures range into
the low to mid 60s. On Wednesday a weak upper level shortwave
embedded in the zonal flow will move through the Upper Midwest
forcing a weak cold front through the area. Some light showers will
be possible with this system on Wednesday with the best chance for
showers along the Missouri/Iowa border. Thursday will feature a
return to southerly flow out ahead of another cold front moving
through the Plains. This will allow high temperatures to reach into
the 70s across the forecast area. Friday, a another upper level
shortwave will drop southeastward from the Northern Plains into the
Midwest which will force the aforementioned cold front though the
area. Showers and thunderstorms will be possible on Friday as the
front moves through thus have chance pops in for the day Friday.
73
&&
.AVIATION...
The next batch of showers and thunderstorms now ongoing across parts
of southeast Kansas tonight. This activity is moving towards the
northeast, which should keep the bulk of the precipitation south of
the terminals. Cannot rule out some of this expanding into the KMKC
but confidence is too low to include at this time. Otherwise,
periodic sct low level clouds will traverse across the TAF sites over
the next few hours. MVFR cigs along with some light fog still remain
possible later tonight into the early morning hours as low level
moisture continues to advect northward. Scattered showers and
thunderstorms may blossom by the morning hours across eastern Kansas
and move across the terminals by the mid to late morning. Confidence
is not high at this time but will include VCTS at this time to
account. Otherwise, winds will strengthen through the day becoming
strong and gusty through the afternoon.
Deroche
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
WFO EAX
AREA FORECAST DISCUSSION
NWS BILLINGS MT
1235 PM MDT SAT APR 14 2012
.SHORT TERM...VALID FOR TDY AND SUN...
WE MADE A SECOND...MINOR UPDATE TO THE FORECAST SO THAT IT CARRIES
SLIGHT CHANCE POPS IN THE MILES CITY AND HYSHAM AREAS TOO. THIS IS
IN RESPONSE TO THE OBSERVED CONVECTIVE DEVELOPMENT IN THAT AREA. A
RELATIVELY DRY BOUNDARY LAYER EXISTS WITH CLOUD BASES AROUND MILES
CITY STILL OVER 7000 FT AGL...BUT RADAR TRENDS SUPPORT THE MENTION
OF SHOWER CHANCES. SCHULTZ
PREVIOUS DISCUSSION...ISSUED AT 916 AM MDT SAT APR 14 2012...
THE FORECAST WAS UPDATED TO INCLUDE LIKELY POPS FOR TODAY OVER THE
FAR SOUTHEASTERN PARTS OF MT...AND TO SHOW SOME SLIGHT CHANCES FOR
SHOWERS AS FAR NORTH AS BAKER. RADAR IMAGERY AT 15 UTC IS SHOWING
A BATCH OF RAIN HEADING NORTH OUT OF SD AND NORTHEASTERN WY...WITH
SIMPLE EXTRAPOLATION OF THIS ACTIVITY TAKING IT INTO CARTER COUNTY
BY 17 UTC. THE 06 UTC GFS SEEMS TO HAVE A GOOD HANDLE ON THIS...AS
IT SHOWS A NOTABLE AREA OF 500-300 HPA Q-VECTOR CONVERGENCE ACROSS
THIS AREA DURING THE DAY. SOME MID-LEVEL FRONTOGENESIS EVEN EXISTS
TO HELP ALONG THE PRECIPITATION...WHICH IS LIKELY WHY RADAR IMAGES
SHOW SOME MODEST BANDED STRUCTURES TO THE RAIN. THE HRRR RUNS FROM
11 AND 12 UTC ALSO SUPPORT SHOWERS ACROSS FAR SOUTHEASTERN MT THIS
AFTERNOON. THE MAIN QUESTIONS ARE HOW FAR NORTH THE MOISTURE MAKES
IT...AND HOW LONG IT COULD LINGER INTO THE EVENING. SOUNDINGS FROM
BAKER ARE NOT ESPECIALLY MOIST...SO WE ONLY INCLUDED SLIGHT CHANCE
POPS THAT FAR NORTH FOR NOW. AS FAR AS THE TEMPORAL QUESTION MARKS
GO...WE WILL TAKE SOMETHING OF A WAIT-AND-SEE APPROACH FOR NOW. IT
LOOKS LIKE DYNAMICS WILL BE WANING AFTER 00 UTC...BUT THE LAST FEW
HRRR RUNS DO LINGER SHOWERS IN SOUTHEASTERN MT INTO THE EVENING.
THE REST OF THE FORECAST FOR TODAY IS ESSENTIALLY UNCHANGED. THERE
SHOULD BE SOME WEAK CONVECTION IN AND CLOSE TO THE HIGHER TERRAIN
AS DIURNAL HEATING LEADS TO A BIT OF INSTABILITY. SCHULTZ
.LONG TERM...VALID FOR MON...TUE...WED...THU...FRI...
NOTHING DRAMATIC TO ADVERTISE IN THE EXTENDED PERIOD WITH
TEMPERATURES NOT DEVIATING TOO FAR FROM SEASONAL NORMALS. WEAK
UPPER LEVEL RIDGING ON MONDAY FOLLOWED BY A WEAK SHORTWAVE ON
TUESDAY. CYCLE REPEATS ITSELF ON WEDNESDAY AND WEDNESDAY NIGHT
INTO THURSDAY...WITH NEITHER WAVE ACTUALLY LOOKING THAT STRONG.
ONE THING OF INTEREST IS MODEL GUIDANCE THROUGH THE PERIOD IS
KEEPING DEWPOINTS IN THE 25 TO 30 DEGREE RANGE...INDICATIVE THAT THE
LOW LEVELS WILL REMAIN FAIRLY DRY AND ANY SHOWER ACTIVITY SHOULD
NOT PRODUCE SIGNIFICANT MOISTURE.
ANOTHER WAVE ON FRIDAY LOOKS FAIRLY BENIGN AND CONTINUED TREND
FEATURED EARLIER IN THE WEEK OF SCATTERED SHOWERS FOR THE MOUNTAINS
AND LARGELY ISOLATED POPS FOR THE PLAINS. BOTH 00Z RUNS OF THE
ECMWF AND GFS HINT AT BROADER RIDGING FOR NEXT WEEKEND...FOR
WARMER TEMPS AND LESS SHOWER ACTIVITY. WENT WITH PERSISTENCE FOR
TEMPERATURES SINCE PATTERN MAY NOT AMPLIFY AS QUICKLY AND TRENDED
WITH DRIER POPS...BELOW CLIMATOLOGICAL NORMALS BUT STILL
INDICATING ISOLATED SHOWERS POSSIBLE. BORSUM
&&
.AVIATION...
LOW LEVEL WINDS WILL TURN EASTERLY TODAY AS SURFACE PRESSURE FALLS
OVER WYOMING. THE AIRMASS WILL BECOME UNSTABLE AND SHOWER ACTIVITY
SHOULD DEVELOP FAVORING HIGHER TERRAIN. THIS WILL FAVOR SHOWERS
FORMING ON THE NORTHEAST ASPECTS OF THE MOUNTAINS AND THEN MOVING
AWAY FROM THE PLAINS. EXPECT SHOWER ACTIVITY TO BE ISOLATED AND
LIGHT OVER THE PLAINS WITH LITTLE IMPACTS TO CEILINGS OR
VISIBILITY. ALONG THE FOOTHILLS AND OVER THE MOUNTAINS...EXPECT
DECREASING CEILINGS WITH AREAS OF IFR POSSIBLE BY LATE AFTERNOON.
KSHR IS THE MOST LIKELY LOCATION TO SEE MVFR CONDITIONS
DEVELOPING. BORSUM
&&
.PRELIMINARY POINT TEMP/POPS...
TDY SUN MON TUE WED THU FRI
-------------------------------------------------------
BIL 057 034/047 031/059 039/063 039/064 043/060 036/061
2/T 25/W 41/B 12/W 21/B 23/W 22/W
LVM 052 029/041 027/056 034/060 037/060 038/055 032/057
2/T 36/W 52/W 23/W 22/W 43/W 32/W
HDN 060 035/052 030/060 035/066 035/066 038/063 036/062
2/T 24/W 41/B 12/W 21/B 23/W 22/W
MLS 064 035/052 030/058 036/065 037/065 038/061 038/060
2/W 23/W 31/B 12/W 21/B 23/W 22/W
4BQ 060 032/055 027/057 034/065 036/066 037/062 037/061
4/W 33/W 32/W 12/W 21/B 33/W 22/W
BHK 062 030/049 027/055 033/063 036/062 037/060 035/056
2/W 23/W 32/W 12/W 21/B 33/W 22/W
SHR 050 035/050 029/056 033/063 035/064 037/061 036/061
4/T 56/W 62/W 12/W 21/B 22/W 32/W
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BILLINGS MT
916 AM MDT SAT APR 14 2012
.SHORT TERM...VALID FOR TDY AND SUN...
THE FORECAST WAS UPDATED TO INCLUDE LIKELY POPS FOR TODAY OVER THE
FAR SOUTHEASTERN PARTS OF MT...AND TO SHOW SOME SLIGHT CHANCES FOR
SHOWERS AS FAR NORTH AS BAKER. RADAR IMAGERY AT 15 UTC IS SHOWING
A BATCH OF RAIN HEADING NORTH OUT OF SD AND NORTHEASTERN WY...WITH
SIMPLE EXTRAPOLATION OF THIS ACTIVITY TAKING IT INTO CARTER COUNTY
BY 17 UTC. THE 06 UTC GFS SEEMS TO HAVE A GOOD HANDLE ON THIS...AS
IT SHOWS A NOTABLE AREA OF 500-300 HPA Q-VECTOR CONVERGENCE ACROSS
THIS AREA DURING THE DAY. SOME MID-LEVEL FRONTOGENESIS EVEN EXISTS
TO HELP ALONG THE PRECIPITATION...WHICH IS LIKELY WHY RADAR IMAGES
SHOW SOME MODEST BANDED STRUCTURES TO THE RAIN. THE HRRR RUNS FROM
11 AND 12 UTC ALSO SUPPORT SHOWERS ACROSS FAR SOUTHEASTERN MT THIS
AFTERNOON. THE MAIN QUESTIONS ARE HOW FAR NORTH THE MOISTURE MAKES
IT...AND HOW LONG IT COULD LINGER INTO THE EVENING. SOUNDINGS FROM
BAKER ARE NOT ESPECIALLY MOIST...SO WE ONLY INCLUDED SLIGHT CHANCE
POPS THAT FAR NORTH FOR NOW. AS FAR AS THE TEMPORAL QUESTION MARKS
GO...WE WILL TAKE SOMETHING OF A WAIT-AND-SEE APPROACH FOR NOW. IT
LOOKS LIKE DYNAMICS WILL BE WANING AFTER 00 UTC...BUT THE LAST FEW
HRRR RUNS DO LINGER SHOWERS IN SOUTHEASTERN MT INTO THE EVENING.
THE REST OF THE FORECAST FOR TODAY IS ESSENTIALLY UNCHANGED. THERE
SHOULD BE SOME WEAK CONVECTION IN AND CLOSE TO THE HIGHER TERRAIN
AS DIURNAL HEATING LEADS TO A BIT OF INSTABILITY. SCHULTZ
.LONG TERM...VALID FOR MON...TUE...WED...THU...FRI...
NOTHING DRAMATIC TO ADVERTISE IN THE EXTENDED PERIOD WITH
TEMPERATURES NOT DEVIATING TOO FAR FROM SEASONAL NORMALS. WEAK
UPPER LEVEL RIDGING ON MONDAY FOLLOWED BY A WEAK SHORTWAVE ON
TUESDAY. CYCLE REPEATS ITSELF ON WEDNESDAY AND WEDNESDAY NIGHT
INTO THURSDAY...WITH NEITHER WAVE ACTUALLY LOOKING THAT STRONG.
ONE THING OF INTEREST IS MODEL GUIDANCE THROUGH THE PERIOD IS
KEEPING DEWPOINTS IN THE 25 TO 30 DEGREE RANGE...INDICATIVE THAT THE
LOW LEVELS WILL REMAIN FAIRLY DRY AND ANY SHOWER ACTIVITY SHOULD
NOT PRODUCE SIGNIFICANT MOISTURE.
ANOTHER WAVE ON FRIDAY LOOKS FAIRLY BENIGN AND CONTINUED TREND
FEATURED EARLIER IN THE WEEK OF SCATTERED SHOWERS FOR THE MOUNTAINS
AND LARGELY ISOLATED POPS FOR THE PLAINS. BOTH 00Z RUNS OF THE
ECMWF AND GFS HINT AT BROADER RIDGING FOR NEXT WEEKEND...FOR
WARMER TEMPS AND LESS SHOWER ACTIVITY. WENT WITH PERSISTENCE FOR
TEMPERATURES SINCE PATTERN MAY NOT AMPLIFY AS QUICKLY AND TRENDED
WITH DRIER POPS...BELOW CLIMATOLOGICAL NORMALS BUT STILL
INDICATING ISOLATED SHOWERS POSSIBLE. BORSUM
&&
.AVIATION...
LOW LEVEL WINDS WILL TURN EASTERLY TODAY AS SURFACE PRESSURE FALLS
OVER WYOMING. THE AIRMASS WILL BECOME UNSTABLE AND SHOWER ACTIVITY
SHOULD DEVELOP FAVORING HIGHER TERRAIN. THIS WILL FAVOR SHOWERS
FORMING ON THE NORTHEAST ASPECTS OF THE MOUNTAINS AND THEN MOVING
AWAY FROM THE PLAINS. EXPECT SHOWER ACTIVITY TO BE ISOLATED AND
LIGHT OVER THE PLAINS WITH LITTLE IMPACTS TO CEILINGS OR
VISIBILITY. ALONG THE FOOTHILLS AND OVER THE MOUNTAINS...EXPECT
DECREASING CEILINGS WITH AREAS OF IFR POSSIBLE BY LATE AFTERNOON.
KSHR IS THE MOST LIKELY LOCATION TO SEE MVFR CONDITIONS
DEVELOPING. BORSUM
&&
.PRELIMINARY POINT TEMP/POPS...
TDY SUN MON TUE WED THU FRI
-------------------------------------------------------
BIL 057 034/047 031/059 039/063 039/064 043/060 036/061
2/T 25/W 41/B 12/W 21/B 23/W 22/W
LVM 052 029/041 027/056 034/060 037/060 038/055 032/057
2/T 36/W 52/W 23/W 22/W 43/W 32/W
HDN 060 035/052 030/060 035/066 035/066 038/063 036/062
2/T 24/W 41/B 12/W 21/B 23/W 22/W
MLS 064 035/052 030/058 036/065 037/065 038/061 038/060
1/B 23/W 31/B 12/W 21/B 23/W 22/W
4BQ 060 032/055 027/057 034/065 036/066 037/062 037/061
4/W 33/W 32/W 12/W 21/B 33/W 22/W
BHK 062 030/049 027/055 033/063 036/062 037/060 035/056
2/W 23/W 32/W 12/W 21/B 33/W 22/W
SHR 050 035/050 029/056 033/063 035/064 037/061 036/061
4/T 56/W 62/W 12/W 21/B 22/W 32/W
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS HASTINGS NE
420 PM CDT SAT APR 14 2012
.SHORT TERM...THROUGH SUNDAY AFTERNOON. THE OBVIOUS CONCERN IS THE
EVOLUTION OF SEVERE CONVECTION OVER AT LEAST THE NEXT 6-8 HOURS.
IN SHORT...THE FIRST ROUND OF STRONG-SEVERE CONVECTION IS IN THE
PROCESS OF EXITING FAR EASTERN PORTIONS OF THE CWA...ESSENTIALLY
BRINGING ROUND 1 TO A CLOSE. THESE STORMS RESULTED IN AT LEAST 3
UNCONFIRMED BRIEF TORNADOES NEAR AND SOUTH OF THE STATE
LINE...ALONG WITH SOME LOCALLY HEAVY RAIN IN EXCESS OF 2 INCHES.
THE CONCERN NOW SHIFTS BACK TO THE FAR WESTERN-SOUTHWESTERN
CWA...AS CLEARING SKIES ARE RAPIDLY DESTABILIZING AREAS CLOSER TO
THE SURFACE DRYLINE FROM SOUTHWEST NEB DOWN ACROSS WESTERN KS. AS
A RESULT...WANT TO EMPHASIZE THAT THIS EVENT IS FAR FROM BEING
OVER.
PARAMETERS FOR ADDITIONAL DEVELOPMENT ARE VERY FAVORABLE FOR
HIGH-END SEVERE...AS THE 110+KT UPPER LEVEL JET STREAK CURRENTLY
MAKING ITS WAY INTO FAR WESTERN KS OVERSPREADS THE AREA.
SUPERCELLS ARE LIKELY WITH 0-6KM BULK SHEAR OF AT LEAST 50KT...AND
WITH LOW LEVEL 0-1KM BULK SHEAR OF 30-40 KT. 0-1KM STORM RELATIVE
HELICITY IS QUITE IMPRESSIVE AS WELL...WITH 300-400+ M2/S2 ACROSS
MUCH OF THE CWA...WHICH COULD ONLY INCREASE INTO THE EVENING HOURS
AS THE LOW LEVEL JET STRENGTHENS. FOLLOWING CONVECTIVE REFLECTIVITY
PROGS FROM LATEST HRRR...ALONG WITH 12Z RUNS OF 4KM WRF-NMM...ALONG
WITH LATEST RUC FIELDS...SIGNIFICANT SURFACE-BASED INSTABILITY
WILL CONTINUE SURGING NORTHEAST INTO THE CWA THROUGH THE NEXT
SEVERAL HOURS WITH LOW LEVEL CAPE IN EXCESS OF 2000 J/KG
PERSISTING WELL INTO THE EVENING. HRRR SUGGESTS A COMBINATION OF
DISCRETE SUPERCELLS AND QUASI LINEAR STORM MODES WILL CONTINUE
WELL INTO THE EVENING...WITH SOUTHERN AND WESTERN PORTIONS OF THE
CWA LIKELY MOST UNDER THE GUN. ALTHOUGH HYDRO ISSUES SEEM TO BE
MINIMAL SO FAR...ANOTHER 1-2 INCHES OF RAIN ACROSS ROUGHLY THE
SOUTHEAST 1/3 OF THE CWA ON TOP OF WHAT FELL EARLIER COULD LEAD TO
SOME ISSUES.
SO FAR...WIND ADVISORY IN EFFECT FOR KS ZONES THROUGH 00Z IS NOT
PANNING OUT VERY WELL WITH CONVECTIVE ACTIVITY INTERFERING...AND
ALTHOUGH NEITHER AN IMMEDIATE CANCELLATION OR AN EXTENSION IS NOT
PLANNED AT THIS TIME...WILL PROBABLY SEE STRONGER SOUTHERLY WINDS
ACTUALLY PICK UP OVERNIGHT AS THE SURFACE LOW DEEPENS TO AROUND
987MB IN THE NORTHEAST CO/SOUTHWEST NEB AREA. SPEAKING OF WIND...A
GOOD CHUNK OF THE CWA WILL ALMOST CERTAINLY NEED AN ADVISORY
DURING THE DAY SUNDAY...AS STRONG WINDS INITIALLY ARE FROM THE
SOUTH...BUT THEN FROM THE WEST AND NORTHWEST BEHIND THE COLD
FRONT. INSERTED A STRONG WIND MENTION INTO THE GRIDS AND HAZARDOUS
WEATHER OUTLOOK...BUT WITH EVERYTHING ELSE GOING ON TODAY WILL
DEFER TO MIDNIGHT SHIFT TO PULL THE TRIGGER ON THE NEXT WIND
HEADLINE...WHICH WILL UNDOUBTEDLY BE MORE ROBUST THAN THE CURRENT
ONE.
AS FOR STORM CHANCES LATE TONIGHT...ONLY HAVE 20-30 PERCENT
CHANCES POST-06Z...AND ALTHOUGH THE VAST MAJORITY OF THE CWA
SHOULD BE FREE OF SEVERE WEATHER BY THEN...COULD FORESEE A
MARGINALLY SEVERE STORMS HANGING ON IN NORTHERN ZONES LATE INTO
THE NIGHT. SHOULD BE A LULL IN PRECIPITATION ACROSS MUCH OF THE
CWA LATE TONIGHT INTO SUNDAY MORNING AS THE SYNOPTIC DRY SLOT
SURGES IN...BUT RAIN SHOWERS WILL GRADUALLY SPREAD INTO THE CWA
FROM WEST TO EAST WRAPPING AROUND THE DEPARTING LOW. THE
COMBINATION OF ANY RAIN SHOWERS WITH THE STRONG WINDS WILL MAKE
THE FORECAST HIGHS IN THE MID 50S TO MID 60S FEEL COLDER THAN IT
MAY SOUND.
.LONG TERM...SUNDAY EVENING THROUGH NEXT SATURDAY. OVERALL FEW
NOTABLE CHANGES MADE TO PREVIOUS FORECAST...WITH FORECAST BASED ON
A GENERAL BLEND OF THE 12Z ECMWF/GFS.
STARTING OFF RIGHT AWAY SUNDAY EVENING...A WIND ADVISORY MAY
CONTINUE FOR A FEW MORE HOURS ESPECIALLY IN NORTHEAST AREAS...BUT
LIKELY NOT BEYOND 03Z AS THE STRONG SURFACE LOW PULLS GRADUALLY
AWAY ACROSS SOUTHERN MN. LINGERED A SLIGHT CHANCE OF LIGHT SHOWERS
INTO THE EVENING HOURS MAINLY ACROSS THE NORTHEAST...BUT DRY AFTER
MIDNIGHT. HEADING INTO MONDAY...LEFT THE MORNING DRY BUT HAVE
20-30 PERCENT CHANCES FOR SHOWERS IN THE AFTERNOON AS A TRAILING
SHORTWAVE TRACKS OUT OF SOUTHERN SD INTO NORTHERN NEB. NEXT SLIGHT
CHANCE FOR SHOWERS ARRIVES IN NORTHEAST COUNTIES FOR TUESDAY NIGHT
AS THE NEXT QUICK MOVING WAVE PASSES BY IN QUASI-ZONAL FLOW ALOFT.
A FAIRLY ACTIVE UPPER PATTERN CONTINUES INTO THE LATTER PART OF
THE WEEK...AND MAINTAINED 20-30 PERCENT CHANCES FOR SHOWERS/STORMS
FROM THURS INTO THURS NIGHT AS THE NEXT WAVE CROSSES THE REGION.
AT THIS TIME...SEVERE WEATHER THREAT APPEARS LOW. BEYOND THURSDAY
NIGHT...MAINTAINED A DRY FORECAST THROUGH SATURDAY AS THERE ARE
SUGGESTIONS OF AT LEAST WEAK SHORTWAVE RIDGING BUILDING INTO THE
PLAINS.
TEMPERATURE WISE THROUGH THE EXTENDED...HAVE MOST DAYS IN THE
LOW-MID 70S FOR HIGHS...EXCEPT FOR COOLER UPPER 50S-LOW 60S ON
MONDAY. AS FOR OVERNIGHT LOWS...COULD EVENTUALLY NEED TO INSERT
SOME FROST WORDING FOR SUNDAY NIGHT AND/OR MONDAY NIGHT WITH LOWS
IN THE MID-UPPER 30S...ALTHOUGH BREEZES MAY REMAIN JUST STRONG
ENOUGH TO PRECLUDE MUCH DEVELOPMENT.
&&
.PREV DISCUSSION... /ISSUED 109 PM CDT SAT APR 14 2012/
AVIATION...18Z KGRI TAF. PLENTY GOING ON DURING THIS 24-HOUR
PERIOD. OF PARAMOUNT IMPORTANCE IS THE RISK FOR SEVERE
THUNDERSTORMS THROUGH THE AFTERNOON AND INTO THE EVENING
HOURS...AND HAVE TEMPO GROUPS WITH A HAIL MENTION GOING TO COVER
THIS. DAMAGING WINDS AND EVEN AN ISOLATED TORNADO IN THE GENERAL
VICINITY OF THE TERMINAL CANNOT BE RULED OUT. OTHERWISE...MVFR CIG
EXPECTED TO HOLD FIRM WELL INTO THIS EVENING...WITH OCCASIONAL IFR
POSSIBLE. AS FOR WINDS...A GUSTY SOUTH-SOUTHEAST COMPONENT WILL
HOLD FIRM THROUGH THE MAJORITY OF THE PERIOD...WITH GUSTS OF AT
LEAST 26KT POSSIBLE. BY THE LAST 6 HOURS OR SO OF THE PERIOD ON
SUNDAY...WINDS WILL TURN MORE SOUTHWESTERLY-WESTERLY AND INCREASE
IN INTENSITY AS SURFACE LOW PRESSURE SWINGS BY TO THE NORTH.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR KSZ005>007-017>019.
&&
$$
PFANNKUCH
AREA FORECAST DISCUSSION
NWS HASTINGS NE
109 PM CDT SAT APR 14 2012
.UPDATE...OTHER THAN THINGS GETTING GOING IN KS ZONES A BIT
EARLIER THAN ANTICIPATED AS EARLY LEAD-SHORTWAVE MOVED IN...THE
WELL-ADVERTISED HIGH END SEVERE WEATHER RISK FOR THE ENTIRE CWA
IS STILL ON TRACK. PDS TORNADO WATCHES ARE OUT CWA-WIDE...AND A
FEW STORMS NEAR AND SOUTH OF THE STATE LINE HAVE ALREADY EXHIBITED
DECENT LOW LEVEL ROTATION. AIRMASS NEVER REALLY HAD A CHANCE TO
TRULY DESTABILIZE WITH EARLY MORNING STRATUS/FOG...BUT RUC MESO-
ANALYSIS INDICATING SIGNIFICANT 0-1KM SHEAR OF 25-30KT...1000-1500
J/KG MLCAPE...AND LOW LCL HEIGHTS OF ONLY AROUND 500M...AS ALSO
EVIDENCED BY STORM CHASER WEB CAMS. ALTHOUGH THERE ARE SO MANY
STORMS ONGOING IN SOUTHERN ZONES AT THIS TIME THAT STORM SCALE
INTERFERENCE MAY BE KEEPING A HIGH END TORNADIC THREAT AT
BAY...ANY DISCRETE STORM WITH UNIMPEDED INFLOW WILL CERTAINLY HAVE
STRONG TORNADO POTENTIAL. THINKING AT THIS POINT THAT THERE COULD
BE AT LEAST TWO DISTINCT ROUNDS OF SUPERCELLS FIRING ACROSS THE
SOUTHERN CWA AND MOVING NORTHEAST THROUGH THIS EVENING...WITH
CURRENT ACTIVITY ONLY BEING ROUND 1. ON A LESSER NOTE...WILL KEEP
WIND ADVISORY GOING IN NORTH CENTRAL KANSAS...BUT CLEARLY SEVERE
CONVECTION IS MAKING THIS HEADLINE LOOK FAR LESS SIGNIFICANT THAN
USUAL.
&&
.AVIATION...18Z KGRI TAF. PLENTY GOING ON DURING THIS 24-HOUR
PERIOD. OF PARAMOUNT IMPORTANCE IS THE RISK FOR SEVERE
THUNDERSTORMS THROUGH THE AFTERNOON AND INTO THE EVENING
HOURS...AND HAVE TEMPO GROUPS WITH A HAIL MENTION GOING TO COVER
THIS. DAMAGING WINDS AND EVEN AN ISOLATED TORNADO IN THE GENERAL
VICINITY OF THE TERMINAL CANNOT BE RULED OUT. OTHERWISE...MVFR CIG
EXPECTED TO HOLD FIRM WELL INTO THIS EVENING...WITH OCCASIONAL IFR
POSSIBLE. AS FOR WINDS...A GUSTY SOUTH-SOUTHEAST COMPONENT WILL
HOLD FIRM THROUGH THE MAJORITY OF THE PERIOD...WITH GUSTS OF AT
LEAST 26KT POSSIBLE. BY THE LAST 6 HOURS OR SO OF THE PERIOD ON
SUNDAY...WINDS WILL TURN MORE SOUTHWESTERLY-WESTERLY AND INCREASE
IN INTENSITY AS SURFACE LOW PRESSURE SWINGS BY TO THE NORTH.
&&
PREV DISCUSSION... /ISSUED 434 AM CDT SAT APR 14 2012/
SHORT TERM...TODAY THROUGH MONDAY NIGHT. PRIMARY FORECAST CONCERN
LIES WITH TODAY/THIS EVENING AND THE SEVERE WEATHER OUTBREAK
EXPECTED ACROSS THE REGION.
ALL IS QUIET CURRENTLY ACROSS THE CWA...UNFORTUNATELY IT WONT BE
STAYING THAT WAY FOR LONG. LOOKING AT THE UPPER LEVEL PROFILER AND
SATELLITE DATA...SEEING SOUTHWESTERLY FLOW ACROSS THE
REGION...WITH THE WAVE THAT BROUGHT US PRECIPITATION LAST NIGHT
CONTINUING TO SHIFT INTO THE GREAT LAKES....WHILE THE LOW PRESSURE
SYSTEM OF INTEREST IS SLIDING EAST THROUGH SRN NV AND INTO AZ. AT
THE SURFACE...WEAK LOW PRESSURE SITS ACROSS THE FRONT RANGE...WITH
THE WARM FRONT DRAPED ROUGHLY ALONG THE OK/KS STATE LINE.
COMPARED TO 24 HOURS AGO...THE BIGGEST CHANGE IN THE
MODELS/FORECAST LIES WITH MODELS SLOWING THE EASTWARD PROGRESS OF
THE SFC DRY LINE INTO THE CWA...AND TO A LESSER EXTENT THE
NORTHWARD PROGRESS OF THE WARM FRONT. THE BIG PICTURE REALLY HASNT
CHANGED SIGNIFICANTLY...WITH THE UPPER LEVEL LOW CURRENTLY OVER
THE SWRN CONUS EXPECTED TO CONTINUE ITS EASTWARD TREK...ENDING UP
ROUGHLY OVER THE 4 CORNERS REGION BY THIS EVENING...WITH MODELS
SHOWING A MORE ELONGATED MID LEVEL LOW REACHING INTO THE NEB
PANHANDLE/SANDHILLS. AS THE MID/UPPER LEVEL SYSTEM APPROACHES WILL
SEE THE SFC LOW DEEPEN...AND AS IT DOES SO...LOOKS TO CENTER
ITSELF OVER THE SWRN NE/NWRN KS/NE CO AREA...ALL THE WHILE PULLING
THE WARM FRONT FURTHER NORTH. LAST NIGHT...THERE WAS DECENT
AGREEMENT AMONG MODELS SHOWING THE DRYLINE PUSHING INTO CENTRAL
PORTIONS OF THE CWA BY THIS EVENING...THATS NOT CASE
ANYMORE...WITH LATEST MODELS NOW SHOWING THE BOUNDARY PERHAPS JUST
STARTING TO CREEP INTO WRN PORTIONS OF THE CWA BY 00Z. THIS HAS
RESULTED IN A WESTWARD SHIFT OF ACCOMPANYING PARAMETERS
/INSTABILITY-SHEAR-ETC/...AND THINKING LAST NIGHT WAS THAT
LOCATIONS NEAR THE WARM FRONT/SFC BOUNDARY...ROUGHLY THE EASTERN
HALF OF THE CWA...WAS UNDER THE GREATEST RISK. NOW THAT CONCERN
EXTENDS BACK WEST ALL THE WAY TO THE CWA BOUNDARY...AND MAINLY
ACROSS OUR SC NEB COUNTIES /THOUGH NC KS IS CERTAINLY NOT OUT OF
THE WOODS/.
EXPECTING TO SEE PRECIPITATION START MOVING IN/DEVELOPING ACROSS
SOUTHERN PORTIONS OF THE CWA AS WE MOVE CLOSER TO SUNRISE...AS
INCREASING MOISTURE/WARM AIR ADVECTION SHIFTS FURTHER NORTH AHEAD
OF/WITH THE SFC WARM FRONT. ALL MODELS...TO VARYING DEGREES OF
TIMING/LOCATION...SHOW COVERAGE EXPANDING AND SHIFTING NORTH THIS
MORNING AND INTO THE AFTERNOON HOURS. WITH INCREASING SHEAR AND
INSTABILITY MAKING ITS WAY NORTH...CANT RULE OUT THAT SOME OF
THESE THUNDERSTORMS WOULD BE ON THE SEVERE SIDE. NOT GOING TO BE
ONE OF THOSE DAYS WHERE WE CAN WAIT AND FOCUS SOLELY ON THE
MID/LATE AFTERNOON HOURS...GOTTA GET THROUGH THE MORNING TOO.
THIS AFTERNOON...ALONG WITH THE MID/UPPER LEVEL LOWS SHIFTING
CLOSER...THE SFC LOW DEEPENING TO THE WEST...ALSO SEE THE A GOOD
MID/UPPER LEVEL JET NOSING INTO THE REGION FROM THE SW. LITTLE
UNCERTAIN WITH THE EXACT LOCATION OF THE WARM FRONT THROUGH THE
DAY...AND HOW MUCH THIS MORNINGS ACTIVITY WILL AFFECT ITS
PROGRESS...BUT MODELS CONTINUE TO SHOW IT LIFTING INTO NORTHERN
PORTIONS OF THE CWA THIS AFTERNOON/BY THIS EVENING. STILL
EXPECTING STRONG INSTABILITY TO DEVELOP S OF THE WARM FRONT/AHEAD
OF THE DRY LINE AS DEWPOINTS REACH NEAR 60 DEGREES...ESP IN
LOCATIONS THAT SEE MORE IN THE WAY OF SUN...WITH VALUES NEAR 3000
J/KG STILL BEING SHOWN BY SOME MODELS. SHEAR WAS NEVER AN
ISSUE...WITH DEEP LAYER SHEAR STILL EXPECTED TO BE NEAR/IN EXCESS
OF 50-60KTS...AND WITH WINDS AT 850MB ALREADY INCREASING/NOSING BY
THIS EVENING...LOW LEVEL SHEAR VALUES ARE ALSO QUITE
CONCERNING...WITH MODELS SHOWING WIDESPREAD VALUES RANGING FROM
25-40 KTS LATER THIS AFTERNOON. THE POTENTIAL REMAINS IN PLACE FOR
VERY LARGE HAIL...DAMAGING WINDS...AND MOST
IMPORTANTLY...STRONG/LONG TRACK TORNADOES...AND HAVE INSERTED THAT
WORDING INTO THE ZONE FORECAST.
THE POTENTIAL FOR SEVERE WEATHER WILL CONTINUE INTO THE EVENING
HOURS...BEFORE THE DRYLINE /AND MAIN THREAT/ FINALLY STARTS TO
PUSH FURTHER EAST THROUGH AND OUT OF THE CWA. KEPT THE LOW POPS
GOING POST 06Z...BUT ITS QUITE POSSIBLE A GOOD CHUNK OF THE CWA
WONT SEE MUCH OF ANYTHING...SOMETHING THAT CAN BE ADJUSTED ONCE WE
HAVE A BETTER HANDLE ON HOW THINGS ARE PLAYING OUT TODAY.
OUTSIDE OF THIS...MAIN CHANGES TO THE FORECAST FOR TODAY WAS TO
LOWER HIGH TEMPERATURES PRIMARILY ACROSS THE NORTH WHICH WILL
LIKELY SEE MORE IN THE WAY OF CLOUD COVER AND PRECIPITATION
THROUGH THE DAY...AND TO INCREASE WIND SPEEDS ACROSS THE CWA.
EXPECTING TO SEE MANY LOCATIONS POTENTIALLY FLIRT WITH WIND ADV
CRITERIA AS THE PRESSURE GRADIENT TIGHTENS UP...AND DECIDED TO GO
WITH A WIND ADVISORY ACROSS NC KS...WHERE THERE IS BETTER
MODEL/GUIDANCE AGREEMENT OF LOCATIONS REACHING CRITERIA. WILL BE
ANOTHER THING THE DAY SHIFT WILL HAVE TO KEEP AN EYE ON.
LOOKING TO SUNDAY/SUNDAY NIGHT...NOT A LOT OF CHANGES MADE TO THE
FORECAST. EXPECTING A COOLER AND BREEZY DAY...WITH PRECIPITATION
CHANCES BEING DRIVEN BY THE MID/UPPER LEVEL LOW PRESSURE SYSTEM
MAKING ITS WAY NORTHEAST THROUGH NEB INTO SD. MODELS CONTINUE TO
SHOW THE NORTHWESTERN PORTIONS OF THE CWA WITH THE BEST OF SEEING
SHOWERS /INSTABILITY IS E/S OF THE CWA/...AND LOW POPS REMAIN
ACROSS THE REMAINDER OF THE CWA...BUT AGAIN IS POSSIBLE ESP SERN
LOCATIONS WONT SEE MUCH. HIGHS FORECAST TO TOP OUT IN THE
50S/60S...AND A SFC COLD FRONT PUSHING THROUGH WILL BRING GUSTY
NORTHWEST WINDS THROUGH THE AFTERNOON. WILL NEED TO MONITOR FOR
THE NEED FOR A WIND ADVISORY. EXPECTING ANY LINGERING
PRECIPITATION TO EXIT THE CWA SUNDAY EVENING.
ANOTHER COOL DAY EXPECTED ON MONDAY...AND THERE IS A SLIGHT CHANCE
FOR A FEW SHOWERS AS A WEAK UPPER LEVEL WAVE LOOKS TO CROSS THE
PLAINS. HIGHS ONCE AGAIN EXPECTED IN THE 50S/60S.
OVERNIGHT LOWS SUNDAY NIGHT AND MONDAY NIGHT ALSO EXPECTED TO BE
COOLER...ACTUALLY NOT FAR FROM NORMAL FOR THIS TIME OF
YEAR...RANGING FROM THE MID 30S TO LOWER 40S.
LONG TERM...STARTING 12Z TUESDAY. GUIDANCE SUGGESTS MID AND UPPER
LEVEL FLOW WILL REMAIN QUASI-ZONAL DURING MUCH OF THE EXTENDED
FORECAST PERIOD...WITH SEVERAL SMALL-SCALE PERTURBATIONS TRAVELING
THROUGH THE MEAN FLOW. AT THIS TIME IT APPEARS MOST OF THESE
PERTURBATIONS SHOULD REMAIN NORTH OF OUR AREA...THUS PRESENTING AN
OVERALL LACK IN KINEMATIC FORCING AND DRY CONDITIONS THROUGH MUCH
OF THE EXTENDED FORECAST PERIOD. THE ONLY EXCEPTION IS LATE
THURSDAY INTO FRIDAY...WHICH IS WHEN THE OPERATIONAL GFS AND EC
BOTH SUGGEST A MORE SIGNIFICANT MID LEVEL SHORT WAVE WILL PUSH
ACROSS THE CENTRAL PLAINS...BRINGING WITH IT CHANCES FOR
PRECIPITATION ACROSS THE ENTIRE CWA. SLIGHT CHANCE TO CHANCE POPS
EXIST ACROSS THE CWA DURING THIS TIME PERIOD AS A RESULT. LITTLE
CHANGE IN THE LOW LEVEL AIRMASS WILL PRESENT CONTINUED ABOVE-
NORMAL TEMPERATURES DURING THE EXTENDED FORECAST PERIOD...WITH
HIGHS IN THE UPPER 60S TO 70S AND LOW IN THE 40S AND 50S.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...WIND ADVISORY UNTIL 7 PM CDT THIS EVENING FOR KSZ005>007-017>019.
&&
$$
UPDATE/AVIATION...PFANNKUCH
SHORT TERM...ADO
LONG TERM...BRYANT
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1005 PM CDT SUN APR 15 2012
.DISCUSSION...
ALL KINDS OF ISSUES TONIGHT. BAND OF RAIN CONTINUES FROM SERGENT
COUNTY UP TOWARDS BJI...AND HAS NOT MOVED MUCH IN THE LAST FEW
HOURS. PRECIP CONTINUES TO BE RAIN SO FAR...AS MUCH OF THE CAA AND
TEMPS DROPPING BELOW FREEZING HAS BEEN OVER THE NORTHWESTERN
COUNTIES. AT ONE POINT IT SEEMED THAT THE COLD AIR COMING DOWN WAS
A BIT SLOWER...AND MUCH OF THE PRECIP WOULD STAY AS RAIN BEFORE
BRIEFLY GOING OVER TO SN BY EARLY MORNING BEFORE MOVING OFF. THE
00Z NAM AND LATEST RUNS OF THE HRRR AND RUC HOWEVER...HAVE BEEN
SPEEDING UP THE COOLING OF THE COLUMN...AND MODEL SOUNDINGS HAVE
THE BAND IN THE SOUTHEAST GOING OVER TO SNOW SHORTLY AFTER 06Z.
WILL CONTINUE TO KEEP THE CHANGE OVER TO SNOW AFTER
MIDNIGHT...WITH SOME ACCUMULATION POSSIBLE IN THE FAR EASTERN
COUNTIES...BUT AT THIS POINT THINK IT WILL STAY BELOW ANY ADVISORY
CRITERIA.
THERE HAS BEEN A SCATTERED BAND OF PRECIP DEVELOPING IN THE BIS
CWA AHEAD OF THE NORTHERN BRANCH SHORTWAVE DIGGING SOUTH INTO THE
AREA. NAM AND GFS ARE IN PRETTY GOOD AGREEMENT ON KEEPING THIS TO
OUR WEST...BUT WILL INCLUDE SOME LOW POPS OUT AROUND KDVL FOR ANY
RAIN/SNOW SHOWERS THAT HAPPEN TO STRAY INTO THE AREA.
WILL LET MOST OF THE WIND ADVISORY EXPIRE AT 10 PM...BUT THE FAR
SOUTHERN COUNTIES HAVE THE 925 WINDS STAYING UP FOR MOST OF THE
NIGHT. BWP WAS STILL GUSTING ABOVE 40 MPH AND GWINNER WAS ALSO
ABOVE CRITERIA. WILL EXTEND THE FAR SOUTHERN COUNTIES UNTIL 09Z
BUT EVERYONE ELSE WILL SEE FALLING SPEEDS.
&&
.AVIATION...
NORTH WINDS WILL STAY RATHER BREEZY IN THE 15 TO 20 KT RANGE WITH
HIGHER GUSTS OVERNIGHT. MOST LOCATIONS ARE MVFR TO IFR AND THIS
WILL CONTINUE THROUGH MUCH OF THE NIGHT. ONLY KFAR AND KBJI WILL
SEE PRECIP...AND -RA AT KFAR SHOULD BE ENDING IN THE NEXT FEW
HOURS. KBJI COULD SEE SOME MIXING WITH -SN TOWARDS MORNING...BUT
THINK THAT VIS WILL STAY IN THE 1-3SM RANGE. CONDITIONS SHOULD
BECOME VFR BY LATE MORNING ACROSS THE FORECAST AREA.
&&
.PREV DISCUSSION... /ISSUED 228 PM CDT SUN APR 15 2012/
SHORT TERM...
CHALLENGING FORECAST MAINLY DUE TO WIND/PCPN AND SNOW ISSUES INTO
TONIGHT AND THEN TEMPS/PCPN CHANCES AGAIN ON WED. TRENDED A BIT
MORE TOWARD THE GFS SOLUTION TODAY WHICH HAS PRETTY GOOD SUPPORT
FROM THE ECMWF/GEM AS WELL. NAM SEEMS TOO FAST IN CLEARING THINGS
OUT TONIGHT.
TONIGHT...STARTING TO SEE OUR FIRST BAND OF RAIN THAT EXTENDED
FROM KDTL TO KFAR DOWN INTO FORMAN COUNTY WEAKENING A BIT. THIS
WAS THE GOOD FRONTOGENETICAL FORCING AREA THAT CAME TOGETHER EARLY
THIS MORNING. AN ENHANCED BAND OF SHOWERS WITH EMBEDDED THUNDER
HAS ENCIRCLED AN AREA FROM KDLH TO KATY WHICH IS NORTH OF THE SFC
WARM FRONT WHICH LIES OVER SOUTHERN MN. THIS AREA CLIPS OUR FAR
SOUTHEAST FA AND THIS WILL PROBABLY BE THE MAIN PCPN AREA
TONIGHT. THIS SHOULD PIVOT A BIT AS THE SFC LOW TRACKS TOWARD
WISCONSIN TONIGHT AND GIVE AREAS FROM KBJI TO KFFM THE BEST
CHANCES OF PCPN TONIGHT. THINK THE BEST FORCING WILL START TO WIND
DOWN AFTER MIDNIGHT AND THEREFORE PCPN AMOUNTS SHOULD WANE THEN
TOO. AS FAR AS SNOW CHANCES GO AM NOT CONVINCED OF MUCH
ACCUMULATION IN THE EAST TONIGHT. HPC SNOW TOTALS WENT UP A TAD
WITH THE 4 INCH LINE BRUSHING AN AREA FROM KBJI TO KPKD. MAIN
QUESTION IS HOW FAST THE COLD AIR COMES IN THIS EVENING AND CAN
CHANGE THE PCPN TYPE OVER TO SNOW. MODEL SOUNDINGS SHOW IT WARM
ENOUGH FOR JUST LIQUID PCPN THRU MIDNIGHT AT KBJI AND THEN SLOWLY
CHANGING OVER AFTER THAT. LIKE MENTIONED BEFORE THE BEST FORCING
AND PCPN SHOULD OCCUR PRIOR TO MIDNIGHT AT KBJI AND THEN TAPER OFF
AFTER. THEREFORE THINK THE PERIOD FOR SNOW MAY BE LIMITED AND WILL
STICK WITH THE IDEA OF AN INCH OR TWO POSSIBLE IN THE EAST AROUND
OR AFTER MIDNIGHT. WIND SPEEDS SHOULD BE STRONGEST EARLY ON AND
BEGIN TO DECREASE A BIT AFTER THAT. CURRENT WIND ADVISORY GOES
THRU 03Z AND WILL KEEP THIS AS IS. THE EVENING SHIFT CAN MONITOR
AND ADJUST THIS AS NEEDED.
MON-WED...WENT AHEAD AND REMOVED THE MONDAY MORNING PCPN CHANCES
IN THE EAST AS THIS SYSTEM CONTINUES TO PULL EAST. DEPENDING ON
CLOUD COVER...TEMPS WILL STAY COOL AS NORTH WINDS WILL STILL BE
WINDING DOWN TOO. SHOULD HAVE PRETTY LIGHT WINDS BY MON NIGHT. SO
AGAIN HOW MUCH CLOUD COVER LINGERS WILL PLAY INTO THE TEMP
FORECAST. TUE LOOKS LIKE THE WARMEST DAY WITH SOUTHERLY RETURN
FLOW AS LONG AS THICKER CLOUDS DO NOT MOVE IN TOO EARLY IN THE
DAY. NEXT SHORT WAVE MOVES IN TUE NIGHT AND WED. TEMPS CONTINUE TO
LOOK MILD ENOUGH TO KEEP THIS EVENT IN THE LIQUID FORM. THIS NEXT
SYSTEM MAY EXIT EAST ALLOWING FOR SOME AFTERNOON SUN ON WED.
LONG TERM (WED NIGHT THROUGH SUN)...
A FAIRLY UNSETTLED EXTENDED PERIOD IS POSSIBLE WITH NW FLOW ALOFT
AND PERIODIC CHANCES FOR SHOWERS. THE BEST CHANCES FOR PRECIP WOULD
BE THU NIGHT INTO FRI...THEN AGAIN SATURDAY WITH TIMING TRICKY IN
THIS FLOW PATTER. THERE COULD BE SOME SNOW MIXING IN DURING THE
NIGHT AND MORNING...BUT OVERALL EXPECT MAINLY RAIN SHOWERS. TEMPS
SHOULD REMAIN SLIGHTLY BELOW NORMAL UNTIL NEXT SUNDAY WHEN WARMER
AIR SHOULD MOVE IN.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...WIND ADVISORY UNTIL 4 AM CDT MONDAY FOR NDZ052-053.
MN...WIND ADVISORY UNTIL 4 AM CDT MONDAY FOR MNZ029>031-040.
&&
$$
JR
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
938 PM EDT SUN APR 15 2012
.SYNOPSIS...
A COLD FRONT WILL MOVE ACROSS THE REGION ON MONDAY AS LOW PRESSURE
RACES FROM THE WESTERN GREAT LAKES INTO QUEBEC. HIGH PRESSURE WILL
THEN MOVE INTO THE AREA FOR TUESDAY INTO WEDNESDAY. THE NEXT AREA
OF LOW PRESSURE MAY MOVE ACROSS ONTARIO WEDNESDAY NIGHT WITH A
COLD FRONT PASSING THROUGH THE REGION ON THURSDAY.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
UPDATE...MADE ADJUSTMENT TO CLOUDS...POPS AND WX FOR MONDAY AS
WELL AS VARIOUS ADJUSTMENTS FOR THE OVERNIGHT. STILL EXPECT MAINLY
VARIABLE CLOUDS OVERNIGHT ALTHOUGH THERE SHOULD BE A TREND TOWARD
CLOUDS INCREASING AS SYSTEM APPROACHES FROM THE WEST. TOWARD
MORNING BROUGH CHANCE POPS INTO THE FAR NORTHWEST. LINE LOOKS GOOD
AT PRESENT ALTHOUGH HRRR INDICATES THIS SHOULD WEAKEN AS IT
APPROACHES SO WANTED TO BEGIN WITH A CHANCE POP. EXPECT THROUGH
THE MORNING AND EARLY AFTERNOON COVERAGE WILL INCREASE SO WENT
WITH LIKELY FROM CENTRAL COUNTIES EAST FROM ABOUT NOON ON. WINDS
CONTINUE TO LOOK GOOD FOR TOMMOROW SO ANTICIPATE THE NEED FOR A
HEADLINE. WILL ALLOW NEXT SHIFT TO PICK TIMING AND LOCATION BASED
ON NEW GUIDANCE.
PREVIOUS...GUSTY SOUTHERLY WINDS ARE EXPECTED THROUGH THE NIGHT
AS LOW PRESSURE OVER THE PLAINS SLOWLY MOVES TOWARD THE REGION.
OTHERWISE VARIABLE AMOUNTS OF HIGH LEVEL CLOUD COVER AND THE
STRONG WARM ADVECTION WILL LEAD TO A WARM NIGHT. MOST LOCATIONS
WILL BE NEAR TO SLIGHTLY ABOVE 60.
BESIDES THE FEW THUNDERSTORMS THAT ARE ATTEMPTING TO CLIP THE
ERIE AREA THROUGH 6 PM IT APPEARS THE THREAT OF RAIN IS VERY LOW.
HOWEVER AS THE COLD FRONT MOVES CLOSER TO THE REGION TOWARD
SUNRISE THERE MAY BE A FEW SCATTERED THUNDERSTORMS THAT DRIFT INTO
THE WESTERN COUNTY WARNING AREA.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY NIGHT/...
THE COLD FRONT WILL MOVE INTO NW OHIO EARLY MONDAY MORNING. THERE
IS MUCH UNCERTAINTY WITH THE AMOUNT OF CONVECTION THAT WILL BE
LOCATED NEAR THE FRONTAL BOUNDARY IN THE MORNING. MOISTURE LEVELS
MAY BE DIFFICULT TO KEEP ELEVATED ON MONDAY IF SOME DEEPER MIXING
CAN OCCUR AHEAD OF THE FRONT. THIS COULD HAVE A LIMITING AFFECT ON
THE THUNDERSTORM DEVELOPMENT AS THE FRONT MOVES TOWARD PA. STRONG
LOW LEVEL JET AHEAD OF THE FRONT WILL BE A FACTOR WITH THE
THUNDERSTORMS THAT CAN DEVELOP. SOME OF THIS WIND MAY BE BROUGHT
TO THE SURFACE WITH THE STRONGEST CONVECTION. HOWEVER THE MAIN
CONCERN WILL BE THE GUSTY WINDS AWAY FROM THE THUNDERSTORMS AS WE
ATTEMPT TO MIX THE STRONGER WINDS TO THE SURFACE WHERE HIGHS GET
INTO THE UPPER 70S. WINDS IN THE WAKE OF THE FRONT WILL ALSO
APPROACH ADVISORY LEVELS FOR A FEW HOURS. DID NOT HOIST A WIND
ADVISORY AT THIS TIME BUT THE POTENTIAL WILL CONTINUE TO BE
MENTIONED IN THE HWO.
HIGH PRESSURE WILL MOVE INTO THE REGION BY TUESDAY AND PERSIST
INTO WEDNESDAY. THIS WILL BRING DRIER AIR INTO THE REGION THAT
WILL ALLOW FOR LARGER DIURNAL RANGES. THE COLDEST NIGHT LOOKS LIKE
IT WILL BE TUESDAY NIGHT WITH MANY LOCATIONS ACROSS THE EASTERN
HALF OF THE AREA DIPPING TO AROUND 30 DEGREES. WARMER BY WEDNESDAY
AFTERNOON WITH HIGHS VERY CLOSE TO SEASONAL LEVELS.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
A WEAK COLD FRONT WILL MOVE THROUGH THE AREA THURSDAY AND HAS A
MINIMAL CHANCE OF PRODUCING SOME SHOWER ACTIVITY. MAINLY DUE TO THE
WEAK UPPER LEVEL AND MOISTURE SUPPORT. LOW PRESSURE WILL MOVE INTO
THE REGION FRIDAY EVENING AND BRING YET ANOTHER ROUND OF SHOWERS TO
THE REGION AS AN UPPER LEVEL TROUGH DIGS INTO THE EASTERN UNITED
STATES.
THE UPPER LEVEL TROUGH WILL LINGER INTO THE WEEKEND AND MOVE LITTLE
AS AMPLIFICATION OF THE RIDGE TAKES PLACE IN THE CENTRAL UNITED
STATES. THIS MEANS A TREND TOWARD COOLER TEMPERATURES DURING THE
WEEKEND. TEMPERATURES WILL LIKELY BE COOL ENOUGH TO SUPPORT THE MIX
OF RAIN AND WET SNOW SATURDAY NIGHT.
MODELS ARE SUGGESTING DRYING CONDITIONS RETURNING FOR SUNDAY INTO
SUNDAY NIGHT AS WEAK HIGH PRESSURE BUILDS EAST OVER THE REGION.
&&
.AVIATION /02Z MONDAY THROUGH FRIDAY/...
GUSTS MAY BECOME INTERMITTENT THIS EVENING...BUT BECOME MORE
CONSISTENT AGAIN PREDAWN. GUSTS TO RAMP UP TO AROUND 30 KNOTS IN
THE MORNING...WITH GUSTS AS HIGH AS 40 KNOTS LIKELY FROM MIDDAY
ONWARD. FEEL CONFIDENT ENOUGH IN THE SURFACE WINDS/GUSTS PREDAWN
TO NOT HAVE ANY LLWS MENTIONED.
BROKEN LINE OF SHOWERS/THUNDERSTORMS TO MARCH ACROSS THE AREA
MONDAY WITH A COLD FRONT. BEST CHANCE FOR STRONG TO SEVERE
THUNDERSTORMS IS FROM CLE/MFD EAST IN THE AFTERNOON AND HAVE GONE
VCTS THERE. VFR EXCEPT WITHIN SHRA/TS. WIND SHIFT TO WEST MONDAY
EVENING AND A GRADUAL DIMINISHING OF WINDS AND GUSTS.
.OUTLOOK...NON-VFR CONDITIONS POSSIBLE MONDAY NIGHT INTO TUESDAY
AND THEN AGAIN WEDNESDAY NIGHT INTO FRIDAY.
&&
.MARINE...
WARM AIR ADVECTION TAKING PLACE OVER THE LAKE WILL LIKELY CAUSE
STRONGER WINDS AT THE SURFACE TO RIDE UP AND OVER THE COLD DOME.
THIS SHOULD KEEP WINDS BELOW SMALL CRAFT ADVISORY CRITERIA AT THE
LAKE SURFACE UNTIL COLD FRONT MOVES THROUGH LATE MONDAY AFTERNOON
AND EVENING.
WILL LIKELY NEED TO HOIST SMALL CRAFT ADVISORIES TOMORROW NIGHT AND
WILL POSSIBLY BE ABLE TO DROP IT BY TUESDAY AFTERNOON AS WINDS
DIMINISH CONSIDERABLY.
GENERALLY LIGHT FLOW EXPECTED INTO THURSDAY AND MARGINAL SMALL CRAFT
WAVES WILL LIKELY DEVELOP THURSDAY NIGHT BUT DIMINISH ON FRIDAY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MULLEN
NEAR TERM...TK/MULLEN
SHORT TERM...MULLEN
LONG TERM...LOMBARDY
AVIATION...OUDEMAN
MARINE...LOMBARDY
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1007 PM CDT SUN APR 15 2012
.UPDATE...
JUST SENT A QUICK GRID AND TEXT UPDATE TO REMOVE POPS IN THE FAR
SOUTHEAST COUNTIES AND RETREND TEMPS...DEW POINTS...AND WINDS
OVERNIGHT. NO MAJOR CHANGES TO THE OVERALL FORECAST.
&&
PREV DISCUSSION... /ISSUED 327 PM CDT SUN APR 15 2012/
DISCUSSION...
THE SFC FRONT IS SLOWLY WORKING ITS WAY INTO THE COASTAL
PLAINS...WITH SCATTERED CONVECTION CONTINUING ALONG THE FRONTAL
BOUNDARY. THE FRONT IS EXPECTED TO STALL ALONG THE COAST LATER
TONIGHT...WITH GOOD CONSENSUS AMONG THE NAM/GFS OF POST-FRONTAL
PRECIPITATION CONTINUING ACROSS OUR SOUTHERN COUNTIES.
HOWEVER...THE 18Z RUC AND 12Z HI-RES BOTH INDICATE THE PRECIP AXIS
WILL SHIFT COMPLETELY SOUTH OF OUR CWA THIS EVENING. HAVE SOMEWHAT
SPLIT THE DIFFERENCE AND KEPT TOKEN POPS ACROSS OUR SOUTHEASTERN
TIER OF COUNTIES FOR THIS EVENING.
AS THE FRONT STALLS ALONG THE COAST OVERNIGHT...THE MID-UPPER
LEVEL TROUGH AXIS WILL REMAIN NORTHWEST OF OUR AREA. THEREFORE
SOME POST-FRONTAL SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP
ACROSS THE SOUTHEASTERN HALF OF THE REGION TOMORROW AND INTO
TOMORROW NIGHT. RAIN CHANCES WILL CLEAR THE AREA ON TUESDAY AS THE
UPPER TROUGH AXIS SLIDES TO THE EAST OF THE REGION AND DRIER NW
FLOW ALOFT SETTLES INTO THE AREA. MOSTLY DRY AND SEASONABLE
CONDITIONS WILL PREVAIL THROUGH THE MIDDLE OF THE WEEK WITH
ONSHORE FLOW RETURNING LATE TUESDAY/EARLY WEDS. THE INCREASING LOW
LEVEL MOISTURE WILL RESULT IN A SLOW WARMING TREND THROUGH THE END
OF THE WEEK.
MID/LONG-RANGE MODELS CONTINUE TO HAVE FAIR CONSENSUS ON AN UPPER
TROUGH/COLD FRONT FOR OUR AREA LATE IN THE WEEK. CURRENT THINKING
IS THAT THE BEST TIME-FRAME FOR RAIN WOULD BE FRI AFTERNOON/NIGHT.
HOWEVER...THIS COULD EASILY SHIFT TO A FRI NIGHT/SAT MORNING OR
LATER SCENARIO GIVEN WE`RE TALKING ABOUT 126-PLUS HRS FROM NOW.
FIRE WEATHER...
ELEVATED TO NEAR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED
ACROSS THE SOUTHERN EDWARDS PLATEAU AND RIO GRANDE PLAINS THROUGH
THIS EVENING IN THE WAKE OF THE COLD FRONT. LOW RELATIVE HUMIDITIES
AND GUSTY NORTHWEST WINDS NEAR 15 MPH WILL CONTINUE THROUGH THE
REMAINDER OF THE AFTERNOON WITH WINDS DECREASING TO 10 TO 15 MPH
AFTER SUNSET. RH VALUES WILL BE SLOWER TO RECOVER. ELEVATED FIRE
WEATHER CONDITIONS ARE EXPECTED ACROSS WESTERN AREAS ON MONDAY
AFTERNOON MAINLY DUE TO LOW HUMIDITIES AS WINDS WILL BE AT OR
BELOW 10 MPH.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 54 81 57 82 60 / - 20 10 - -
AUSTIN BERGSTROM INTL AIRPORT 52 81 55 82 56 / - 20 10 - -
NEW BRAUNFELS MUNI AIRPORT 52 80 56 81 57 / - 20 10 - -
BURNET MUNI AIRPORT 49 78 52 80 55 / - - - 0 -
DEL RIO INTL AIRPORT 51 84 57 86 63 / - - - 0 -
GEORGETOWN MUNI AIRPORT 49 79 51 81 56 / - 10 10 - -
HONDO MUNI AIRPORT 50 81 55 84 58 / - 20 10 0 -
SAN MARCOS MUNI AIRPORT 53 80 57 81 58 / - 20 10 - -
LA GRANGE - FAYETTE REGIONAL 60 80 60 80 60 / - 40 30 10 -
SAN ANTONIO INTL AIRPORT 54 81 58 82 60 / - 20 10 - -
STINSON MUNI AIRPORT 55 81 60 83 60 / - 20 10 - -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...02
SYNOPTIC/GRIDS...26
PUBLIC SERVICE/DATA COLLECTION...19
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
646 PM CDT SUN APR 15 2012
.AVIATION...
A WEAK DRY SURFACE RIDGE PATTERN COUPLED WITH DRY WESTERLIES ALOFT
WILL RESULT IN MOSTLY CLEAR VFR CONDITIONS OVER ALL TAF SITES
TONIGHT AND MONDAY. A WEAK DISTURBANCE APPROACHING FROM THE WEST
LATE MONDAY AND MONDAY NIGHT WILL BRING INCREASING MID AND UPPER
LEVEL CLOUDINESS TO THE AREA. I-35 CORRIDOR TERMINALS VARIABLE
CLOUDS NEAR 3 THSD AGL BECOMING MOSTLY CLEAR AFTER 03Z. LIGHT
NORTH WINDS BECOMING LIGHT NORTHEAST MONDAY. KDRT TERMINAL VFR
CLEAR. KDRT WINDS LIGHT NORTH TONIGHT AND EARLY MONDAY BECOMING
LIGHT EASTERLY BY MIDDAY.
&&
.PREV DISCUSSION... /ISSUED 327 PM CDT SUN APR 15 2012/
DISCUSSION...
THE SFC FRONT IS SLOWLY WORKING ITS WAY INTO THE COASTAL
PLAINS...WITH SCATTERED CONVECTION CONTINUING ALONG THE FRONTAL
BOUNDARY. THE FRONT IS EXPECTED TO STALL ALONG THE COAST LATER
TONIGHT...WITH GOOD CONSENSUS AMONG THE NAM/GFS OF POST-FRONTAL
PRECIPITATION CONTINUING ACROSS OUR SOUTHERN COUNTIES.
HOWEVER...THE 18Z RUC AND 12Z HI-RES BOTH INDICATE THE PRECIP AXIS
WILL SHIFT COMPLETELY SOUTH OF OUR CWA THIS EVENING. HAVE SOMEWHAT
SPLIT THE DIFFERENCE AND KEPT TOKEN POPS ACROSS OUR SOUTHEASTERN
TIER OF COUNTIES FOR THIS EVENING.
AS THE FRONT STALLS ALONG THE COAST OVERNIGHT...THE MID-UPPER
LEVEL TROUGH AXIS WILL REMAIN NORTHWEST OF OUR AREA. THEREFORE
SOME POST-FRONTAL SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP
ACROSS THE SOUTHEASTERN HALF OF THE REGION TOMORROW AND INTO
TOMORROW NIGHT. RAIN CHANCES WILL CLEAR THE AREA ON TUESDAY AS THE
UPPER TROUGH AXIS SLIDES TO THE EAST OF THE REGION AND DRIER NW
FLOW ALOFT SETTLES INTO THE AREA. MOSTLY DRY AND SEASONABLE
CONDITIONS WILL PREVAIL THROUGH THE MIDDLE OF THE WEEK WITH
ONSHORE FLOW RETURNING LATE TUESDAY/EARLY WEDS. THE INCREASING LOW
LEVEL MOISTURE WILL RESULT IN A SLOW WARMING TREND THROUGH THE END
OF THE WEEK.
MID/LONG-RANGE MODELS CONTINUE TO HAVE FAIR CONSENSUS ON AN UPPER
TROUGH/COLD FRONT FOR OUR AREA LATE IN THE WEEK. CURRENT THINKING
IS THAT THE BEST TIME-FRAME FOR RAIN WOULD BE FRI AFTERNOON/NIGHT.
HOWEVER...THIS COULD EASILY SHIFT TO A FRI NIGHT/SAT MORNING OR
LATER SCENARIO GIVEN WE`RE TALKING ABOUT 126-PLUS HRS FROM NOW.
FIRE WEATHER...
ELEVATED TO NEAR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED
ACROSS THE SOUTHERN EDWARDS PLATEAU AND RIO GRANDE PLAINS THROUGH
THIS EVENING IN THE WAKE OF THE COLD FRONT. LOW RELATIVE HUMIDITIES
AND GUSTY NORTHWEST WINDS NEAR 15 MPH WILL CONTINUE THROUGH THE
REMAINDER OF THE AFTERNOON WITH WINDS DECREASING TO 10 TO 15 MPH
AFTER SUNSET. RH VALUES WILL BE SLOWER TO RECOVER. ELEVATED FIRE
WEATHER CONDITIONS ARE EXPECTED ACROSS WESTERN AREAS ON MONDAY
AFTERNOON MAINLY DUE TO LOW HUMIDITIES AS WINDS WILL BE AT OR
BELOW 10 MPH.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 54 81 57 82 60 / - 20 10 - -
AUSTIN BERGSTROM INTL AIRPORT 52 81 55 82 56 / - 20 10 - -
NEW BRAUNFELS MUNI AIRPORT 52 80 56 81 57 / - 20 10 - -
BURNET MUNI AIRPORT 49 78 52 80 55 / - - - 0 -
DEL RIO INTL AIRPORT 51 84 57 86 63 / - - - 0 -
GEORGETOWN MUNI AIRPORT 49 79 51 81 56 / - 10 10 - -
HONDO MUNI AIRPORT 50 81 55 84 58 / - 20 10 0 -
SAN MARCOS MUNI AIRPORT 53 80 57 81 58 / - 20 10 - -
LA GRANGE - FAYETTE REGIONAL 60 80 60 80 60 / 20 40 30 10 -
SAN ANTONIO INTL AIRPORT 54 81 58 82 60 / - 20 10 - -
STINSON MUNI AIRPORT 55 81 60 83 60 / - 20 10 - -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...02
SYNOPTIC/GRIDS...26
PUBLIC SERVICE/DATA COLLECTION...22
AREA FORECAST DISCUSSION...UPDATED
NWS GREEN BAY WI
854 PM CDT SUN APR 15 2012
.UPDATE...THE SITN FOR THE REST OF THE NIGHT STARTING TO BECOME
CLEARER. STRONGEST SFC PRESSURE GRADIENT SHIFTG E OF THE AREA NOW.
THAT COMBINED WITH SLIGHT STABILIZATION OF THE BOUNARY LAYER
SHOULD SOON CUT DOWN ON ANY MIXING INTO STRONGER WINDS ALOFT
OUTSIDE OF RAIN AREAS...AND RESULT IN A DECR IN THE GUSTS THAT
HAVE BEEN OCCURRING OVER THE SRN PART OF THE FCST AREA THE PAST
FEW HRS.
THE POTENTIAL FOR GUSTS WITHIN RAIN SHAFTS STILL IN QUESTION.
NARROW BAND OF SHRA/TSRA OUT NEAR THE MISSISSIPPI HAS BEEN GETTING
BETTER ORGANIZED WITHIN THE PAST HR. THAT WL STILL POSE SOME RISK
OF STRONGER GUSTS WHEN IT WORKS EWD LATER TNGT. 850 MB FLOW
PROGGED BY THE RUC TO PEAK AT 60-70KTS THE NEXT FEW HRS...THEN
DECR FM WEST TO EAST...POSSIBLY BEFORE THE PCPN ARRIVES. NO SVR
GUSTS OCCURRING WITH THE LINE NOW NOR HAVE THERE BEEN THIS
EVENING. BUT THE LINE IS ALMOST PARALLEL TO THE LOW-LVL WINDS
NOW...AND WL BECOME AT LEAST A LITTLE MORE NORMAL TO THE WINDS BY
THE TIME IT REACHES OUR AREA LATER IN THE NGT. THE BOTTOM LINE IS
IT/S PROBABLY GOING TO BE IMPOSSIBLE TO COME OUT WITH AN ALL-CLEAR
TYPE STATEMENT. BASED ON HOW THINGS LOOK NOW...WL PROBABLY END UP
NEEDING TO KEEP ALIVE AT LEAST THE POSSIBILITY OF ISOLD STG GUSTS.
WL BE DOING A MORE COMPREHENSIVE FCST UPDATE WITHIN THE
NEXT HR AS NEED TO LOOK AT PLACEMENT/TIMING OF POPS THE REST OF
THE NGT. WL GET UPDATE OUT ASAP...BUT PROBABLY A LITTLE LATER THAN
I/D NORMALLY LIKE.
SKOWRONSKI
&&
.PREV DISCUSSION...ISSUED AT 753 PM CDT SUN APR 15 2012...
UPDATE...HAVE BEGUN TO PULL BACK ON SVR WORDING/HILIGHTING IN THE
FCST PRODUCTS. THIS IS TRICKY BECAUSE THE THREAT HAS NOT
ENDED...BUT VERY LIMITED DESTABILIZATION SEEMS TO REALLY BE
HOLDING THINGS BACK. SFC DWPTS BACK IN W-C WI HAVE ACTUALLY EDGED
BACK A BIT AS THERE WAS MIXING INTO DRIER AIR ALOFT. LOCAL MESO
PLOTS CLEARLY SHOW SBCAPE AND MLCAPES DECRG DURING THE PAST
SEVERAL HOURS. IT REALLY SEEMS LIKE THE MAIN THREAT IS GOING TO BE
MIXING OF STRONGER GRADIENT WINDS DOWN TO THE SFC WITH PCPN. BUT
IN ORDER FOR THAT TO HAPPEN...WE/VE GOT TO GET PCPN GOING IN THE
FCST AREA. AND THAT CONTINUES TO BE VERY SLOW TO HAPPEN.
THE STRONGEST WINDS WE/VE HAD THUS FAR HAVE ACTUALLY BEEN OUTSIDE
OF PCPN AREAS. SOME LATE-DAY SUN BACK IN CENTRAL WI ALLOWED ENOUGH
SFC-BASED DESTABILIZATION TO MIX INTO STRONGER WINDS ALOFT...AND
RESULTED IN SOME GUSTS APPROACHING 40 KTS. THAT MAY CONT INTO THE
EVENING...THOUGH IT WL BE TOUGHER TO MAINTAIN THE NECESSARY VERY
STEEP LOW-LEVEL LAPSE RATES AFTER DARK.
SKOWRONSKI
DISCUSSION ISSUED AT 619 PM CDT SUN APR 15 2012...
UPDATE...CONVECTIVE TRENDS STILL NOT EASY TO GET A GRASP ON WITH
ANY CONFIDENCE. PCPN CURRENTLY GOING ARND THE FCST AREA...WITH
CELLULAR DEVELOPMENT NEAR THE UPPER SYSTEM LIFTG NWD ACRS
MN/IA/FAR NW WI. LARGE BAND OF SHRA/TSRA STREAMING NE FM MO WAS
CLIPPING THE SE PART OF THE FCST AREA AT TIMES...BUT MOST OF THE
STORMS IN THAT AREA DIDN/T APPEAR TO BE ANYTHING SPECIAL. LOOKS
LIKE A MORE ORGANIZED LINE MAY BE TAKING SHAPE FM IRK-W OF
STL...BUT EXTRAPOLATING THE MVMT OF THAT LINE WOULD KEEP IT SE OF
THE AREA. SO...WE ARE IN A HOLDING PATTERN. MAY NEED TO WAIT FOR
THE WRN STORMS TO SHIFT EWD...BUT THAT WON/T HAPPEN ANY TIME
SOON. THE OTHER OPTION IS FOR NEW STORMS TO FILL-IN BTWN THE TWO
AREAS OF PCPN OUT THERE NOW. THAT MAY BE HELD BACK SOME BY UPR DRY
SLOT...AND THE RGN BEING IN RFQ OF STG UPPER SPEED MAX. GIVEN THE
VERY STG SHEAR IN PLACE...IT/S GOING TO BE TOUGH TO GIVE UP ON THE
THREAT EVEN WITH WHAT WOULD NORMALLY BE ONLY MARGINAL INSTABILITY
IN PLACE. THE STG SHEAR WOULD ALSO MAINTAIN A SVR THREAT LATER
INTO THE NGT THAN WOULD NORMALLY BE THE CASE.
SKOWRONSKI
DISCUSSION ISSUED AT 316 PM CDT SUN APR 15 2012...
SHORT TERM...TNGT AND MON. MAIN FCST ISSUE REMAINS THE SVR THREAT
ACROSS THE FCST AREA THIS EVENING. OTHER POTENTIAL PROBLEMS
INCLUDE: POTENTIAL DRY SLOT ENDING PCPN OVER PARTS OF NE WI LATER
TONIGHT AND TEMPS ON MON.
THE 20Z MSAS SFC ANALYSIS SHOWED AN AREA OF LOW PRES CENTERED OVER
EAST-CENTRAL NEBRASKA WITH A WRMFNT EXTENDED E-NE THRU SRN MN INTO
CENTRAL WI. A CDFNT STRETCHED SOUTHWARD FROM THE LOW THRU THE
CENTRAL PLAINS. VISIBLE SATL IMAGERY INDICATED CLEARING SKIES OVER
MUCH OF IA WITH CUMULUS CLOUDS STARTING TO GROW ACROSS WRN IA.
RADAR MOSAIC DID SHOW SOME NON-SEVERE CONVECTION OVER SE WI HEADED
TOWARD LK MI.
A SHORTWAVE TROF OVER THE CENTRAL PLAINS IS FCST TO LIFT NEWD INTO
THE UPR MS VALLEY REGION TNGT. THE ASSOCIATED SFC LOW WL TRACK NE
AND REACH CENTRAL SECTIONS OF UPR MI BY DAYBREAK. THE WRMFNT WL
CONT TO SLOWLY LIFT NORTH TOWARD NRN WI THIS EVENING...WITH THE
TRAILING CDFNT FROM THE LOW PRES PUSHING EAST INTO CENTRAL WI WELL
AFTER MIDNIGHT. ANTICIPATE CONVECTION TO FIRE ACROSS MN/IA LATE
THIS AFTERNOON AS SUFFICIENT MSTR (DEW PTS IN THE 60S)...INSTABILITY
(CAPES > 1K J/KG...SUB-ZERO LI`S) AND LIFT FROM A NEARLY COUPLED JET
STRUCTURE...CDFNT) ALL INTERACT TO QUICKLY ALLOW TSTMS TO FORM.
THESE STORMS WL LIKELY TURN SEVERE AND HEAD E-NE INTO WI THIS
EVENING BEFORE WEAKENING/DISSIPATING OVERNIGHT. MDLS ACTUALLY DRY
SLOT MUCH OF NE WI DURING THE OVERNIGHT PERIOD...THUS THE MAJORITY
OF THE SEVERE WEATHER WL BE TO OUR WEST WITH PRIMARILY GUSTY WINDS
ACCOMPANYING ANY TSTM ACTIVITY. HAVE LEFT PCPN AS RAIN...ALTHO
COLDER AIR FILTERING INTO NORTH-CENTRAL WISCONSIN LATE COULD MIX A
FEW WET SNOWFLAKES WITH THE RAIN.
WEAKENING SHORTWAVE TROF/SFC LOW CROSS NORTHERN SECTIONS OF THE
GREAT LKS MON MORNING WITH THE CDFNT COMPLETING ITS PASSAGE THRU
ERN WI. COLDER AIR AND WRAP-AROUND MOISTURE WL OVERSPREAD THE FCST
AREA WITH NEARLY STEADY OR SLOWLY FALLING TEMPS AND SCATTERED RAIN
OR SNOW SHOWERS THRU THE DAY. THERE WL BE A MINOR ACCUMULATION
ACROSS THE NORTH (LESS THAN AN INCH)...MAINLY ON GRASSY SURFACES.
LASTLY...A BLUSTERY DAY ON TAP WITH WIND GUSTS TO 30 MPH POSSIBLE
AS THE PRES GRADIENT IS TIGHT BETWEEN THE LOW PRES OVER SE ONTARIO
AND INCOMING HI PRES OVER THE UPR MS VALLEY.
LONG TERM...MONDAY NIGHT THROUGH NEXT SUNDAY. MAIN UPPER SYSTEM
WITH WRAP AROUND MOISTURE TO EXIT NORTHEAST WISCONSIN MONDAY
NIGHT. TRAILING WEAK SHORT WAVE TROUGH MONDAY NIGHT MAY TEND TO
KEEP A FEW CLOUDS AROUND SO WILL CONTINUE WITH A OVERNIGHT CLEARING
TREND AS A HIGH PRESSURE RIDGE DRIFTS TOWARD THE STATE AND UPPER
PATTERN FLATTENS TO A ZONAL FLOW. OTHERWISE A COLD NIGHT IN STORE
DUE TO THE RATHER COOL START FROM MONDAY AFTERNOON.
NEXT PCPN CHC ASSOCIATED WITH A NORTHERN STREAM WAVE WITH FRONTAL
SYSTEM APPROACHING FROM THE NORTHERN PLAINS TOWARD WEDNESDAY.
LATEST TRENDS SUGGEST A TIMING OF CENTRAL AND NORTH CENTRAL LATE
TUESDAY NIGHT BEFORE EXITING EASTERN WISCONSIN WEDNESDAY EVENING.
SYSTEM WILL BE ON THE NOSE OF A 80 KNOT UPPER JET BUT WAA PATTERN
SUPPORTS ELEVATED CONVECTION...AT LEAST EARLY IN THE EVENT AND
OVER MAINLY NORTHERN WISCONSIN...WITH FURTHER CONVECTION LIKELY
ALONG THE COLD FRONT LATER WEDNESDAY.
MODELS DIVERGE WITH SOLUTIONS FOR THE THURSDAY NIGHT INTO FRIDAY
PERIOD. ECMWF MORE NORTH AND STRONGER WITH A SURFACE LOW TRACKING
OVER SOUTHERN WISCONSIN WHILE THE GFS IS FURTHER SOUTH. BOTH
MODELS PROG A STRONG H8 LOW ALONG A BAROCLINIC ZONE FOR A NICE QPF
EVENT...JUST LOCATION IS QUESTIONABLE. WILL CONTINUE A BLEND FOR
THIS PACKAGE.
UPPER HEIGHTS BUILD FOR NEXT WEEKEND FOR A MAINLY DRY FORECAST AT
THIS TIME.
&&
.AVIATION...MAIN CHG FOR THE 00Z TAF PKG WAS TO TRY AND LINE-UP
PCPN TIMING. AND THAT/S DIFFICULT WITH CONSIDERABLE UNCERTAINTY
OVER CONVECTIVE DEVELOPMENT THIS EVENING. DECIDED TO BRING MAIN
CHC OF TSRA OVER E-C WI IN WITH BAND OF SHRA/TSRA STREAMING NEWD
OUT OF MO. OUT WEST...CHC WL COME WITH TAIL OF CONVECTIVE LINE
FORMING ACRS MN...BUT NWD MVT OF THAT LINE WL KEEP IT TO OUR W FOR
A WHILE.
SKOWRONSKI
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
1248 AM CDT MON APR 16 2012
.AVIATION...
A COLD FRONT CONTINUES TO MOVE THROUGH ARKANSAS AT THIS TIME. THE
LINE OF SHOWERS AND THUNDERSTORMS WILL EXIT SOUTHEAST ARKANSAS BY
10Z. CLEAR SKIES WILL FOLLOW BEHIND THE PRECIPITATION. THE FRONT
WILL STALL JUST SOUTHEAST OF ARKANSAS. A WAVE MOVING ALONG THE
FRONT TOMORROW EVENING SHOULD BRING HIGH CLOUDS TO THE SOUTHEAST
SECTION OF THE STATE. VFR CONDITIONS WILL DOMINATE ONCE THE RAIN
EXITS THE AREA.
&&
.PREV DISCUSSION... /ISSUED 1006 PM CDT SUN APR 15 2012/
UPDATE...
HAVE UPDATED THE MAJORITY OF FORECAST THROUGH THE OVERNIGHT HOURS
AS SEVERE THREAT CONTINUES TO WIND DOWN THIS EVENING. ONLY
MINIMAL WARNINGS WERE NEEDED THIS EVENING AS TORNADIC STORMS WERE
NEVER REALLY ABLE TO GET GOING DUE TO THE LACK OF LOW LEVEL
INSTABILITY WITH ONLY A FEW BOW ECHO STRUCTURES BEING ABLE TO GET
ESTABLISHED.
WHAT THREAT DOES REMAIN FOR THE STATE HAS PUSHED OFF TO THE EAST
AND NORTHEAST AND THE TORNADO WATCH HAS BEEN DISCONTINUED FOR THE
LITTLE ROCK COUNTY WARNING AREA. HOWEVER...SEVERAL MORE HOURS OF
SHOWERS WITH EMBEDDED THUNDER WILL PERSIST BEFORE ENDING FROM WEST
TO EAST OVERNIGHT.
FORECAST UPDATED TO ADJUST PRECIPITATION CHANCES BASED ON RADAR
TRENDS AND TEMPERATURES AS MANY AREAS ALREADY CLOSE TO OVERNIGHT
LOWS. ALL PRODUCTS OUT.
PREV DISCUSSION... /ISSUED 747 PM CDT SUN APR 15 2012/
UPDATE...
HAVE UPDATED 1ST AND 2ND PERIOD GRIDS TO REFLECT RECENT RADAR AND
SFC OBSERVATION TRENDS. MAIN BAND OF SHOWERS AND EMBEDDED
THUNDERSTORMS STRETCHES FROM MENA UP THROUGH CLARKSVILLE AND
HARRISON IN THE WEST...AND EL DORADO TO BATESVILLE IN THE EAST.
RAPID REFRESH RUC AS WELL AS OTHER HIGH RESOLUTION MODELS
CONTINUE TO INDICATE THE BACK EDGE OF THIS LINE WILL CLEAR A
HARRISON-MENA LINE BY ROUGHLY 10 PM...A BATESVILLE-LITTLE ROCK-
CAMDEN LINE AROUND 1 AM...AND FINALLY MONTICELLO SHORTLY BEFORE
DAY BREAK MONDAY MORNING. HAVE ADJUSTED POP GRIDS ACCORDINGLY.
THE THREAT THREAT FOR TORNADOES...DAMAGING WINDS AND LARGE HAIL
SEEMS TO BE QUICKLY DIMINISHING GIVEN RADAR TRENDS AND INSTABILITY
INDICES. HAVE ALREADY TRIMMED BACK SOME WESTERN COUNTIES FROM
TORNADO WATCH 179. WILL CONTINUE TO MONITOR RADAR TRENDS OVER THE
NEXT FEW HOURS...AND FURTHER TRIM COUNTIES WHEN/WHERE POSSIBLE.
OTHERWISE JUST TWEAKED TEMPS AND WINDS FOR THE OVERNIGHT HOURS.
ALL UPDATED PRODUCTS AND GRIDS ARE OUT.
PREV DISCUSSION... /ISSUED 615 PM CDT SUN APR 15 2012/
AVIATION...
THE 00Z TAFS WILL BE OUT SHORTLY.
PRIMARY CONCERNS FOR THIS TAF CYCLE WILL BE THUNDERSTORMS. LEADING
EDGE OF SQUALL LINE WAS LOCATED FROM JUST EAST OF ARKADELPHIA NE
THROUGH CONWAY AND UP THROUGH MOUNTAIN VIEW AS OF 2300Z. EXPECT
THIS LINE TO AFFECT KLIT BY RIGHT AT 00Z...KPBF BY 01-02Z...AND
KLLQ AROUND 02Z. WILL ADVERTISE PREVAILING -SHRA WITH VCTS AND
TEMPO TSRA AND MVFR CONDITIONS THROUGH ROUGHLY 04Z FOR ALL SITES
EXCEPT KHRO. BACK EDGE OF LINE IS APPROACHING KHRO AND SHOULD PUSH
EAST OF THERE BY 02Z- 03Z...EAST OF KLIT BY ROUGHLY 07Z AND
FINALLY EAST OF KLLQ BY 08Z- 09Z. AFTER LINE PUSHES THROUGH...A
QUICK RETURN TO VFR CONDITIONS SHOULD BE SEEN...WITH SKC 4-6HRS
AFTER LINE PUSHES THROUGH.
PREV DISCUSSION... /ISSUED 303 PM CDT SUN APR 15 2012/
SHORT TERM...TONIGHT THROUGH WEDNESDAY NIGHT
STORMS HAVING SOME DIFFICULTY INTENSIFYING IN WESTERN ARKANSAS
EARLY THIS AFTERNOON. INSTABILITY GRADUALLY INCREASING...AND
WOULD EXPECT PRECIPITATION TO CONGEAL INTO MORE OF A LINE AS
IT MOVES INTO CENTRAL/EASTERN SECTIONS OF THE STATE THIS EVENING.
SOME STORMS COULD BE SEVERE...WITH WIND DAMAGE THE MAIN CONCERN.
MAIN STORM SYSTEM WILL MOVE WELL TO THE NORTH ON MONDAY...AND THE
FRONT TRIGGERING THE PRECIPITATION WILL STALL FOR A TIME JUST
SOUTHEAST OF THE STATE. GIVEN THIS...ISOLATED TO SCATTERED SHOWERS
AND THUNDERSTORMS COULD LINGER SOUTHEAST OF LITTLE ROCK. OTHERWISE...
CLEARING WILL OCCUR FARTHER NORTH AND WEST...WITH SLIGHTLY
COOLER/DRIER AIR.
PRECIPITATION CHANCES WILL FINALLY COME TO AN END IN THE
SOUTHEAST MONDAY EVENING AS HIGH PRESSURE BUILDS INTO THE REGION
FROM THE PLAINS. THIS WILL KICK THE FRONT TOWARD THE SOUTHEAST
UNITED STATES.
THE REMAINDER OF THE PERIOD WILL FEATURE TRANQUIL CONDITIONS.
TEMPERATURES TUESDAY AND WEDNESDAY WILL BE MOSTLY ABOVE NORMAL.
LONG TERM...THURSDAY THROUGH SUNDAY
FORECAST WILL START OFF DRY AS NEARLY ZONAL FLOW WILL BE IN PLACE
ACROSS THE CENTRAL CONUS AT THE START OF THE LONG TERM.
HOWEVER...UPPER LEVEL TROUGH WILL EXIT THE ROCKIES BY
FRI...DEEPENING OVER THE PLAINS. THIS WILL PUSH A COLD FRONT SOUTH
ACROSS AR BY FRI EVENING. HAVE PRECIP CHANCES STARTING LATE THU
NIGHT ACROSS THE NW...THEN SPREADING SE DURING THE DAY ON FRI AS THE
FRONT TRAVERSES THE STATE. PRECIP CHANCES THEN DECREASE FROM NW TO
SE BY FRI NIGHT INTO SAT AS HIGH PRESSURE DIVES SE ACROSS THE PLAINS.
DRY CONDITIONS WILL THEN PERSIST THROUGH PRETTY MUCH THE REST OF THE
LONG TERM AS NW UPPER FLOW WILL BE DOMINANT ACROSS THE CENTRAL
CONUS.
&&
.PRELIMINARY POINT TEMPS/POPS...
BATESVILLE AR 72 49 74 49 / 10 10 0 10
CAMDEN AR 80 55 80 51 / 20 10 0 10
HARRISON AR 70 46 73 49 / 10 10 0 10
HOT SPRINGS AR 79 54 78 51 / 10 10 0 10
LITTLE ROCK AR 78 55 77 53 / 10 10 0 10
MONTICELLO AR 80 58 79 54 / 20 10 0 10
MOUNT IDA AR 77 48 77 49 / 10 10 0 10
MOUNTAIN HOME AR 73 46 75 48 / 10 10 0 10
NEWPORT AR 73 49 75 51 / 20 10 0 10
PINE BLUFF AR 78 56 78 53 / 20 10 0 10
RUSSELLVILLE AR 75 48 78 50 / 10 10 0 10
SEARCY AR 76 46 75 51 / 10 10 0 10
STUTTGART AR 77 53 76 54 / 20 10 0 10
&&
.LZK WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
AVIATION...51
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1144 PM CDT SUN APR 15 2012
.AVIATION...
WINDY CONDITIONS EXPECTED THROUGH 17/00Z. SOUTHWEST WINDS 20 TO
30 KTS...GUSTING 35 KTS WILL SHIFT TO THE WEST AND NORTHWEST BY
12Z. BKN-OVC LOW CLOUDS RESULTING IN MOSTLY MVFR CONDITIONS TO
ARRIVE BY 12Z WITH CLEARING SKIES BY 21Z. VFR CONDITIONS WITH
WINDS DECREASING TO AROUND 10 KTS TOWARD SUNSET. NICHOLS
&&
.PREV DISCUSSION... /ISSUED 337 PM CDT SUN APR 15 2012/
SYNOPSIS...
12Z UA ANALYSIS HAS A NEGATIVELY TILTED EXTRATROPICAL CYCLONE
OVER THE PLAINS. 850 AND 700MB WARM AND COLD FRONTS RAN FROM THE
UPPER LOW OVER NEBRASKA INTO SOUTH DAKOTA AND MINNESOTA. THE COLD
FRONTS DROPPED SOUTH FROM THE LOW INTO THE SOUTHERN PLAINS. A LLJ
OF 50-70 KNOTS RAIN FROM THE GULF COAST INTO THE GREAT LAKES
HELPING TO TRANSPORT MOISTURE NORTH FROM THE GULF.
18Z SFC ANALYSIS HAS A LOW NEAR KODX WITH A SECONDARY LOW NEAR KYKN.
THE WARM FRONT RAN NORTHEAST INTO SOUTHERN MINNESOTA AND THEN EAST
INTO CENTRAL WISCONSIN. THE COLD FRONT RAN FROM THE KYKN LOW SOUTH
THROUGH THE EASTERN PARTS OF KANSAS...OKLAHOMA...AND TEXAS. A SUBTLE
TROF RAN FROM THE KYKN LOW INTO NORTHEAST MISSOURI. A NARROW BAND OF
60 DEWPOINTS FROM WISCONSIN SOUTH THROUGH ILLINOIS AND THE LOWER
MISSISSIPPI VALLEY. OUTSIDE OF THIS BAND DEW POINTS WERE IN THE 50S.
DEW POINTS IN THE 30S AND 40S WERE ACROSS THE PLAINS.
SHORT TERM...TONIGHT AND MONDAY
BASED ON CURRENT RUC TRENDS THE BETTER RAIN CHANCES WILL BE ACROSS
THE EASTERN CWFA THIS EVENING. THE WINDOW OF OPPORTUNITY FOR ANY
SEVERE STORMS IS STARTING TO CLOSE. THE SUBSTANTIAL CAP ON THE 18Z
SOUNDING IS THE LIMITING FACTOR. IF THE CAP DOES NOT BREAK BY SUNSET
THEN THE CHANCES FOR ANY SEVERE STORMS WILL RAPIDLY DECREASE.
MOST OF THE PRECIPITATION THIS EVENING WILL BE DONE BY 10 PM EXCEPT
FOR THE FAR EASTERN PARTS OF THE CWFA. WHATEVER CONVECTION IS STILL
PRESENT IN THE CWFA AT 03Z WILL EXIT THE CWFA BY MIDNIGHT. AFTER
MIDNIGHT QUIET ALBEIT WINDY CONDITIONS WILL BE SEEN ACROSS THE AREA.
WRAP AROUND CLOUDS WILL MOVE ACROSS THE CWFA MONDAY MORNING WITH
SOME SHOWERS OVER ROUGHLY THE NORTHERN HALF OF THE CWFA. SKIES WILL
SLOWLY CLEAR DURING THE AFTERNOON HOURS. THE COMBINATION OF CLOUDS
AND PRECIPITATION DURING THE MORNING HOURS WILL HOLD TEMPERATURES TO
BELOW NORMAL.
LONG TERM...MONDAY NIGHT THROUGH NEXT SUNDAY
THE MODELS HAVE A WEAK DISTURBANCE THAT MOVES THROUGH THE AREA LATE
MONDAY NIGHT/TUESDAY MORNING. SOME MODELS INITIATE PRECIP WITH THIS
FEATURE WHILE OTHERS DO NOT. FOR NOW HAVE OPTED TO KEEP THE SCHC
POPS BUT MOISTURE AVAILABILITY FOR ANYTHING TO DEVELOP IS
QUESTIONABLE. THE FACT THERE IS A WEAK DISTURBANCE MOVING THROUGH
THE AREA INDICATES MORE CLOUDS WILL BE PRESENT WHICH WILL HAVE AN
AFFECT ON TEMPERATURES. HIGH PRESSURE OVER THE AREA WILL RESULT IN
LIGHT WINDS WHICH WILL ALLOW TEMPERATURES TO COOL. FREEZING
TEMPERATURES ARE QUESTIONABLE BUT SOME PATCHY FROST MIGHT OCCUR IN
AND IMMEDIATELY SOUTH OF THE HWY 20 CORRIDOR.
AFTER A QUIET TUESDAY AFTERNOON/EVENING THE NEXT SYSTEM APPROACHES
THE AREA FROM THE PLAINS. MODELS SHOW THIS SYSTEM TO BE MORE
VIGOROUS SO THE CHANCES FOR PRECIPITATION SHOULD BE BETTER. THUS THE
SCHC/CHC POPS AFTER MIDNIGHT LOOK REASONABLE GIVEN THE TIMING.
ON WEDNESDAY THIS SYSTEM WILL MOVE ACROSS THE AREA BRINGING ANOTHER
CHANCE OF RAIN. POPS HAVE BEEN INCREASED TO HIGH CHC OVER MOST OF
THE AREA BUT MAY NEED TO BE INCREASED FURTHER TO LIKELY IF CURRENT
TRENDS WITH THE MODELS CONTINUE.
WEDNESDAY NIGHT ON...
MODEL CONSENSUS MAINTAINS AN ACTIVE NORTHWEST FLOW WITH SEVERAL
DISTURBANCES MOVING THROUGH IT. THE INITIAL WAVE ON WEDNESDAY EXITS
THE AREA WED EVENING SO THE SCHC/CHC POPS LOOK REASONABLE. MODELS
CONTINUE TO DISAGREE ON POSITION AND TIMING BUT ANOTHER STORM SYSTEM
WILL MOVE THROUGH THE AREA IN THE THURSDAY THROUGH FRIDAY EVENING
TIME PERIOD. CONSENSUS GIVES MAINLY CHC POPS WITH THE HIGHEST POPS
CENTERED ON THURSDAY NIGHT.
CONSENSUS HAS A WEAK DISTURBANCE MOVING THROUGH THE AREA ON
SATURDAY. MOISTURE IS QUESTIONABLE RIGHT NOW SO THE SCHC POPS BY THE
CONSENSUS LOOKS REASONABLE. RIGHT NOW SUNDAY LOOKS DRY WITH HIGH
PRESSURE MOVING THROUGH THE AREA. 08
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
NICHOLS
AREA FORECAST DISCUSSION
NWS PADUCAH KY
200 AM CDT MON APR 16 2012
.UPDATE...
ISSUED AT 155 AM CDT MON APR 16 2012
MADE ADJUSTMENTS TO POPS/WX AND TEMPERATURES THROUGH 18Z. USED A
COMBINATION OF SHORT TERM MODELS TO GET THE FORECAST. SLOWED DOWN
THE DEPARTURE OF PRECIPITATION OF THE PRECIPITATION IN THE EAST.
THE FINE LINE ASSOCIATED WITH THE WIND SHIFT STILL PRODUCING WIND
GUSTS TO 30+ MPH WITH SOME DECREASE BEHIND THE LINE. THE FINE LINE
HAS OUTRACED THE MAIN PRECIPITATION SHIELD. ONLY ISOLATED
LIGHTNING STRIKES EXPECTED FOR THE REST OF THE NIGHT.
UPDATE ISSUED AT 844 PM CDT SUN APR 15 2012
THIS NEAR TERM DISCUSSION IS ISSUED TO ACKNOWLEDGE THE EXPIRATION
OF THE EARLIER LAKE WIND ADVISORY AT 7 PM CDT...AND THE RECENT
CANCELLATION OF THE TORNADO WATCH NUMBER 180 FOR
CARTER...RIPLEY...WAYNE AND BUTLER COUNTIES IN SOUTHEAST MISSOURI.
GOES IMAGERY DERIVED LIFTED INDEX VALUES HAVE BEEN SHOWING A
GRADUAL TREND TOWARD A MORE STABLE ENVIRONMENT AND THE
PRECIPITABLE WATER VALUES SUGGEST THAT THE MAIN PLUME WILL BE
FIXED WITH THE VICINITY OF CURRENT CONVECTION.
THE PREFERRED 3KM HRRR MODEL GUIDANCE SUGGESTS THAT THE SURFACE-
BASED PEAK HELICITIES /ALSO SUGGESTED BY THE 4KM NAM-WRF...12KM
NAM AND 40KM GFS GUIDANCE ON SATURDAY/ AND CAPE WOULD DIMINISH
AFTER MOVING OUT OF SOUTHEAST MISSOURI BETWEEN THE 23Z SUNDAY -
03Z MONDAY /6-9 PM CDT SUNDAY NIGHT/.
WITH THAT IN MIND...ATTEMPTED TO BLEND THE HRRR GUIDANCE TIMING OF
THE PRECIPITATION ACROSS THE WFO PAH CWA FOR THE REST OF TONIGHT
AND INTO MONDAY MORNING. IN ADDITION...UTILIZED DIFFERENTIAL
POP/WEATHER FOR THUNDERSTORMS VS. RAINSHOWERS AS THE ELEVATED
INSTABILITY DECREASES OVERIGHT AND INTO MONDAY MORNING.
WILL LIKELY MAKE ANOTHER INTERIM UPDATE BEFORE MIDNIGHT TO ADDRESS
TEMPERATURES AND WINDS IN AND AROUND THE CONVECTIVE RAIN SHIELD.
&&
.SHORT TERM...(TONIGHT THROUGH TUESDAY)
ISSUED AT 205 PM CDT SUN APR 15 2012
THE MAIN FOCUS IN THE SHORT TERM WILL BE THE PASSAGE OF A COLD
FRONT LATE TONIGHT INTO MONDAY MORNING AND THE SHOWERS...
THUNDERSTORMS...AND OTHER WEATHER PHENOMENA ASSOCIATED WITH IT.
A LINE OF THUNDERSTORMS BISECTING THE STATE OF MISSOURI FROM
NORTHEAST TO SOUTHWEST AT THE TIME OF THIS WRITING IS EXPECTED TO
PROGRESS EASTWARD WITH THE AFOREMENTIONED FRONTAL SYSTEM THIS
EVENING AND OVERNIGHT.
AS THE SYSTEM MOVES EASTWARD THIS AFTERNOON AND EVENING...MODELS
ARE INDICATING AN INCREASE IN INSTABILITY AND SHEAR VALUES. WITH
ML CAPE VALUES APPROACHING 2000 J/KG AND DEEP LAYER SHEAR OF 50+
KTS...EXPECT STORMS TO INTENSIFY INTO A QLCS WITH THE POSSIBILITY
OF A COUPLE OF EMBEDDED SUPERCELLS.
BY LATE EVENING INTO THE EARLY MORNING HOURS...STORMS WILL LIKELY
WEAKEN AS INSTABILITY AND WIND SHEAR DECREASE A BIT. AS RESULT...
THE STORM PREDICTION CENTER HAS ALL BUT THE EASTERN THIRD OF OUR
CWA IN A SLIGHT RISK AREA FOR SEVERE THUNDERSTORMS. STORMS SHOULD BE
EXITING THE SOUTHEAST CORNER OF OUR CWA BY 3-4 PM MONDAY AFTERNOON.
AS IS OFTEN THE CASE...MODEL RUNS CONTINUE TO SLOW DOWN THE FORWARD
PROGRESS OF A PARTICULAR SYSTEM...SO LATER SHIFTS MAY HAVE TO
ADJUST ACCORDINGLY. IN THE WAKE OF THIS SYSTEM...HIGH PRESSURE
WILL DOMINATE THROUGH THE END OF THE SHORT TERM PERIOD.
GUSTY SOUTH WINDS OF 20 TO 30 MPH THIS AFTERNOON WILL DECREASE TO
10 TO 20 MPH AND VEER AROUND TO THE SOUTHWEST OVERNIGHT...THEN OUT
OF THE WEST STARTING MONDAY MORNING.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 205 PM CDT SUN APR 15 2012
BY MID WEEK...A ZONAL FLOW PATTERN WILL BECOME ESTABLISHED ACROSS
THE NATIONS MID SECTION. AS HIGH PRESSURE DEPARTS TO THE EAST...WARM
SOUTHERLY WINDS WILL RETURN IN THE LOW LEVELS. TEMPERATURES ARE
FORECAST TO REACH THE MID TO UPPER 70S BOTH WEDNESDAY AND THURSDAY
AFTERNOONS WITH PLENTY OF SUNSHINE BOTH DAYS.
THE CHANCE FOR SHOWERS AND THUNDERSTORMS WILL RETURN TO THE FORECAST
LATE THURSDAY INTO FRIDAY AS A DEVELOPING STORM SYSTEM APPROACHES
FROM THE PLAINS. DETERMINISTIC MODELS HAVE BEEN RATHER INCONSISTENT
ON TIMING THIS SYSTEM. MOST RECENT GFS OPERATIONAL RUNS HAVE FAVORED
A DEEPER AND SLOWER SOLUTION...WHILE RECENT ECMWF RUNS HAVE BEEN
FAIRLY CONSISTENT WITH A MORE PROGRESSIVE SOLUTION THAT SHIFTS MUCH
OF THE PRECIPITATION TO THE EAST OF THE AREA BY THE WEEKEND. THE
LATEST GFS AND ECMWF ENSEMBLES TEND TO FAVOR THIS APPROACH. AS A
RESULT...CURRENT FORECAST INCLUDES INCREASING SHOWER AND STORM
CHANCES THURSDAY NIGHT OVER THE WEST...PEAKING FRIDAY AND FRIDAY
EVENING...THEN DEPARTING SOUTHWEST INDIANA AND WESTERN KENTUCKY LATE
FRIDAY NIGHT AND EARLY SATURDAY.
IN THE WAKE OF THIS SYSTEM...COOLER WEATHER WILL RETURN NEXT WEEKEND
AS A NORTHWEST UPPER LEVEL FLOW PATTERN TAKES HOLD. HIGHS WILL DROP
BACK INTO THE 60S...WITH LOWS IN THE 40S BOTH WEEKEND DAYS. BOTH THE
15/12Z GFS AND ECMWF HINT AT THE POSSIBILITY FOR SOME VERY LIGHT
RAIN SATURDAY NIGHT AND SUNDAY. HOWEVER...GIVEN THE LOW CONFIDENCE
THAT FAR OUT...WILL KEEP CONDITIONS DRY FOR NOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1200 AM CDT MON APR 16 2012
AT 0455Z...LEADING EDGE OF THE CONVECTIVE ACTIVITY RAN FROM KFWC TO
KPAH. WINDS SHIFT BRIEFLY WEST AND GUST 30 TO 35 KTS...THEN BACK
TO SSW. LIGHTNING CONTINUES TO FADE...SO THUNDER MAY BE LIMITED.
HOWEVER...WILL CARRY SHRA AND TEMPO TSRA AS THE ACTIVITY MOVES
THROUGH OVER THE NEXT FEW HOURS. AFTER THAT...CLOUDS CLEAR IN THE
WAKE OF THE ACTIVITY...WITH WINDS VEERING MORE TO THE WEST...GUSTY
MAINLY THROUGH THE MORNING HOURS...TAILING OFF IN THE AFTERNOON.
WINDS SHOULD GO LIGHT MONDAY EVENING...WITH HIGH CLOUDS MOVING
BACK OVER THE AREA MAINLY EAST OF THE MISSISSIPPI RIVER.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
UPDATE...PS
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1200 AM CDT MON APR 16 2012
.UPDATE...
ISSUED AT 844 PM CDT SUN APR 15 2012
THIS NEAR TERM DISCUSSION IS ISSUED TO ACKNOWLEDGE THE EXPIRATION
OF THE EARLIER LAKE WIND ADVISORY AT 7 PM CDT...AND THE RECENT
CANCELLATION OF THE TORNADO WATCH NUMBER 180 FOR
CARTER...RIPLEY...WAYNE AND BUTLER COUNTIES IN SOUTHEAST MISSOURI.
GOES IMAGERY DERIVED LIFTED INDEX VALUES HAVE BEEN SHOWING A
GRADUAL TREND TOWARD A MORE STABLE ENVIRONMENT AND THE
PRECIPITABLE WATER VALUES SUGGEST THAT THE MAIN PLUME WILL BE
FIXED WITH THE VICINITY OF CURRENT CONVECTION.
THE PREFERRED 3KM HRRR MODEL GUIDANCE SUGGESTS THAT THE SURFACE-
BASED PEAK HELICITIES /ALSO SUGGESTED BY THE 4KM NAM-WRF...12KM
NAM AND 40KM GFS GUIDANCE ON SATURDAY/ AND CAPE WOULD DIMINISH
AFTER MOVING OUT OF SOUTHEAST MISSOURI BETWEEN THE 23Z SUNDAY -
03Z MONDAY /6-9 PM CDT SUNDAY NIGHT/.
WITH THAT IN MIND...ATTEMPTED TO BLEND THE HRRR GUIDANCE TIMING OF
THE PRECIPITATION ACROSS THE WFO PAH CWA FOR THE REST OF TONIGHT
AND INTO MONDAY MORNING. IN ADDITION...UTILIZED DIFFERENTIAL
POP/WEATHER FOR THUNDERSTORMS VS. RAINSHOWERS AS THE ELEVATED
INSTABILITY DECREASES OVERIGHT AND INTO MONDAY MORNING.
WILL LIKELY MAKE ANOTHER INTERIM UPDATE BEFORE MIDNIGHT TO ADDRESS
TEMPERATURES AND WINDS IN AND AROUND THE CONVECTIVE RAIN SHIELD.
&&
.SHORT TERM...(TONIGHT THROUGH TUESDAY)
ISSUED AT 205 PM CDT SUN APR 15 2012
THE MAIN FOCUS IN THE SHORT TERM WILL BE THE PASSAGE OF A COLD
FRONT LATE TONIGHT INTO MONDAY MORNING AND THE SHOWERS...
THUNDERSTORMS...AND OTHER WEATHER PHENOMENA ASSOCIATED WITH IT.
A LINE OF THUNDERSTORMS BISECTING THE STATE OF MISSOURI FROM
NORTHEAST TO SOUTHWEST AT THE TIME OF THIS WRITING IS EXPECTED TO
PROGRESS EASTWARD WITH THE AFOREMENTIONED FRONTAL SYSTEM THIS
EVENING AND OVERNIGHT.
AS THE SYSTEM MOVES EASTWARD THIS AFTERNOON AND EVENING...MODELS
ARE INDICATING AN INCREASE IN INSTABILITY AND SHEAR VALUES. WITH
ML CAPE VALUES APPROACHING 2000 J/KG AND DEEP LAYER SHEAR OF 50+
KTS...EXPECT STORMS TO INTENSIFY INTO A QLCS WITH THE POSSIBILITY
OF A COUPLE OF EMBEDDED SUPERCELLS.
BY LATE EVENING INTO THE EARLY MORNING HOURS...STORMS WILL LIKELY
WEAKEN AS INSTABILITY AND WIND SHEAR DECREASE A BIT. AS RESULT...
THE STORM PREDICTION CENTER HAS ALL BUT THE EASTERN THIRD OF OUR
CWA IN A SLIGHT RISK AREA FOR SEVERE THUNDERSTORMS. STORMS SHOULD BE
EXITING THE SOUTHEAST CORNER OF OUR CWA BY 3-4 PM MONDAY AFTERNOON.
AS IS OFTEN THE CASE...MODEL RUNS CONTINUE TO SLOW DOWN THE FORWARD
PROGRESS OF A PARTICULAR SYSTEM...SO LATER SHIFTS MAY HAVE TO
ADJUST ACCORDINGLY. IN THE WAKE OF THIS SYSTEM...HIGH PRESSURE
WILL DOMINATE THROUGH THE END OF THE SHORT TERM PERIOD.
GUSTY SOUTH WINDS OF 20 TO 30 MPH THIS AFTERNOON WILL DECREASE TO
10 TO 20 MPH AND VEER AROUND TO THE SOUTHWEST OVERNIGHT...THEN OUT
OF THE WEST STARTING MONDAY MORNING.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 205 PM CDT SUN APR 15 2012
BY MID WEEK...A ZONAL FLOW PATTERN WILL BECOME ESTABLISHED ACROSS
THE NATIONS MID SECTION. AS HIGH PRESSURE DEPARTS TO THE EAST...WARM
SOUTHERLY WINDS WILL RETURN IN THE LOW LEVELS. TEMPERATURES ARE
FORECAST TO REACH THE MID TO UPPER 70S BOTH WEDNESDAY AND THURSDAY
AFTERNOONS WITH PLENTY OF SUNSHINE BOTH DAYS.
THE CHANCE FOR SHOWERS AND THUNDERSTORMS WILL RETURN TO THE FORECAST
LATE THURSDAY INTO FRIDAY AS A DEVELOPING STORM SYSTEM APPROACHES
FROM THE PLAINS. DETERMINISTIC MODELS HAVE BEEN RATHER INCONSISTENT
ON TIMING THIS SYSTEM. MOST RECENT GFS OPERATIONAL RUNS HAVE FAVORED
A DEEPER AND SLOWER SOLUTION...WHILE RECENT ECMWF RUNS HAVE BEEN
FAIRLY CONSISTENT WITH A MORE PROGRESSIVE SOLUTION THAT SHIFTS MUCH
OF THE PRECIPITATION TO THE EAST OF THE AREA BY THE WEEKEND. THE
LATEST GFS AND ECMWF ENSEMBLES TEND TO FAVOR THIS APPROACH. AS A
RESULT...CURRENT FORECAST INCLUDES INCREASING SHOWER AND STORM
CHANCES THURSDAY NIGHT OVER THE WEST...PEAKING FRIDAY AND FRIDAY
EVENING...THEN DEPARTING SOUTHWEST INDIANA AND WESTERN KENTUCKY LATE
FRIDAY NIGHT AND EARLY SATURDAY.
IN THE WAKE OF THIS SYSTEM...COOLER WEATHER WILL RETURN NEXT WEEKEND
AS A NORTHWEST UPPER LEVEL FLOW PATTERN TAKES HOLD. HIGHS WILL DROP
BACK INTO THE 60S...WITH LOWS IN THE 40S BOTH WEEKEND DAYS. BOTH THE
15/12Z GFS AND ECMWF HINT AT THE POSSIBILITY FOR SOME VERY LIGHT
RAIN SATURDAY NIGHT AND SUNDAY. HOWEVER...GIVEN THE LOW CONFIDENCE
THAT FAR OUT...WILL KEEP CONDITIONS DRY FOR NOW.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1200 AM CDT MON APR 16 2012
AT 0455Z...LEADING EDGE OF THE CONVECTIVE ACTIVITY RAN FROM KFWC TO
KPAH. WINDS SHIFT BRIEFLY WEST AND GUST 30 TO 35 KTS...THEN BACK
TO SSW. LIGHTNING CONTINUES TO FADE...SO THUNDER MAY BE LIMITED.
HOWEVER...WILL CARRY SHRA AND TEMPO TSRA AS THE ACTIVITY MOVES
THROUGH OVER THE NEXT FEW HOURS. AFTER THAT...CLOUDS CLEAR IN THE
WAKE OF THE ACTIVITY...WITH WINDS VEERING MORE TO THE WEST...GUSTY
MAINLY THROUGH THE MORNING HOURS...TAILING OFF IN THE AFTERNOON.
WINDS SHOULD GO LIGHT MONDAY EVENING...WITH HIGH CLOUDS MOVING
BACK OVER THE AREA MAINLY EAST OF THE MISSISSIPPI RIVER.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
1154 PM CDT SUN APR 15 2012
.DISCUSSION...
06Z TAF ISSUANCE.
&&
.AVIATION...
TSRA CONTINUES TO INCREASE ACROSS SE TX THIS EVENING...NOW JUST W
OF BPT N TO TOLEDO BEND. EXPECTING THE STRONGEST TSRA POSSIBLE
BETWEEN 06-12Z FOR AEX/BPT/LCH...AND 10-14Z FOR LFT/ARA. FOR
THIS...PLACED TEMPO GROUPS FOR TSRA ALONG WITH IFR CEILINGS/VSBY
DURING THESE TIME PERIODS. FOR THE REMAINDER OF THE FORECAST
PERIOD...THE BOUNDARY IS EXPECTING TO STALL ACROSS SE TX THRU C
LA...YIELDING SHRA WITH INTERMITTENT TSRA DURING THIS TIME.
&&
.PREV DISCUSSION... /ISSUED 934 PM CDT SUN APR 15 2012/
UPDATE...
LINE OF SHOWERS AND A FEW STRONG THUNDERSTORMS BECOMING A BIT MORE
ORGANIZED OVER EASTERN TEXAS ALONG SURFACE BOUNDARY. WATER VAPOR
IMAGERY SHOWS AN UPPER LEVEL LOW OVER THE UPPER MIDWEST WITH AN
UPPER LEVEL DISTURBANCE AND JET STREAK SWINGING AROUND IT AND OUT
OF THE SOUTHWEST U.S. THIS DISTURBANCE WILL BEGIN TO ENHANCE UPPER
LEVEL DIVERGENCE AND PLACE THE FORECAST AREA IN A MORE FAVORABLE
RIGHT ENTRANCE REGION OF JET OVERNIGHT...AND HELP KICK THE SURFACE
BOUNDARY SLOWLY TO THE EAST...WITH BEST DEVELOPMENT OF
THUNDERSTORM ACTIVITY ALONG THE LINE NOTED AROUND AND AFTER
16/09Z.
LIKE THE LATEST RUC HANDLING OF THE CONVECTION AND WILL USE A
COMBO OF THE 16/00Z RUC AND NAM12 FOR THE REMAINDER OF THE NIGHT.
IN THIS SCENARIO...BEST CHANCE OF RAIN WILL BE WEST OF AN
ALEXANDRIA TO LAKE CHARLES LINE...AND WILL HAVE LIKELY POPS IN
THESE AREAS...TAPERING TO CHANCE OVER ACADIANA...MAINLY FOR SOME
STRAY SHOWERS DEVELOPING AHEAD OF THE LINE OFF THE GULF AND INTO
SOUTH CENTRAL LOUISIANA BEFORE DAYBREAK. SEVERE THREAT SEEMS TO
BECOMING MORE LIMITED...WITH MARGINAL LOW LEVEL INSTABILITY...
HOWEVER MAYBE SOME ISOLATED STRONG WIND GUSTS OR HAIL...AND
FREQUENT LIGHTNING WILL STILL BE POSSIBLE. PRECIPITABLE WATER ON
LATEST KLCH SOUNDING WAS AT 1.5 INCHES AND IS EXPECTED TO CONTINUE
TO INCREASE. THUS...WITH THE EXPECTED SLOW MOVEMENT OF THE SURFACE
BOUNDARY...SOME LOCALLY HEAVY RAINFALL WILL BE POSSIBLE AND WILL
KEEP MENTION OF THAT IN THE WEATHER GRIDS. RAINFALL RATES AROUND 2
INCHES PER HOUR WILL BE POSSIBLE WITH THE STORMS ALONG THE LINE.
FOR THE COASTAL WATERS...GRADIENT BEGINNING TO RELAX SOME. SMALL
CRAFT ADVISORY IS EXPECTED TO CONTINUE THROUGH-OUT THE NIGHT INTO
MONDAY NIGHT FOR THE OUTER WATERS...AS IT WILL TAKE SOME TIME FOR
THE SEAS TO FALL BELOW 7 FEET.
RUA
PREV DISCUSSION... /ISSUED 727 PM CDT SUN APR 15 2012/
UPDATE...
HAVE UPDATED FORECAST TO REMOVE WIND ADVISORY HEADLINE. WIND
ADVISORY WAS ALLOWED TO EXPIRE AT 7 PM CDT AS SUSTAINED SOUTHERLY
WINDS HAVE DECREASED TO BELOW 20 MPH.
UPPER AIR SOUNDING FROM KLCH AT 16/00Z SHOWS AN INCREASE IN
MOISTURE WITH PRECIPITABLE WATER NOW UP TO 1.5 INCHES COMPARED TO
0.9 INCHES 12 HOURS AGO. CAP HAS ALSO WEAKENED...BUT STILL ENOUGH
TO KEEP THUNDERSTORM ACTIVITY IN CHECK. SCATTERED ACTIVITY
SKIRTING THE WESTERN PORTIONS OF THE FORECAST AREA...WHERE SURFACE
BOUNDARY HAS PROVIDED ENOUGH LIFT TO GET SOME ACTIVITY GOING. AT
THE PRESENT...NAM12 SEEMS TO BE HAVING A BETTER HANDLE ON
CONVECTION THAN OTHER MODELS. ALTHOUGH...RIGHT ENTRANCE REGION OF
JET IS EXPECTED TO NEAR FORECAST AREA OVERNIGHT...WHICH MAY BE
WHAT IS NEEDED TO GET CONVECTION INITIATED AND MORE ORGANIZED...WHICH
IS WHAT OTHER GUIDANCE IS BANKING ON. IF CURRENT TRENDS CONTINUE...MAY
HAVE TO ADJUST POPS DOWNWARD EAST OF A LAKE CHARLES TO LEESVILLE
LINE FOR THE OVERNIGHT PERIOD. AT THIS POINT...WITH INCREASING
MOISTURE CONTENT...AND EXPECTED SLOW MOVEMENT OF SURFACE BOUNDARY...HEAVY
RAINFALL MAY BE THE BIGGEST CONCERN LATER ON TONIGHT INTO MONDAY.
RUA
PREV DISCUSSION... /ISSUED 622 PM CDT SUN APR 15 2012/
DISCUSSION...
00Z TAF ISSUANCE.
AVIATION...
SHRA/TSRA BEGINNING TO INCREASE JUST WEST OF THE REGION...APPROACHING
LFK. SCT SHRA/TSRA WILL BE POSSIBLE FURTHER E ACROSS SE TX/C AND
SW LA BY 02-04Z...AND ACROSS SC LA BY 04-06Z. EXPECTING THE
STRONGEST TSRA POSSIBLE BETWEEN 04-08Z FOR AEX/BPT/LCH...AND
08-12Z FOR LFT/ARA. FOR THIS...PLACED TEMPO GROUPS FOR TSRA ALONG
WITH IFR CEILINGS/VSBY DURING THESE TIME PERIODS. FOR THE
REMAINDER OF THE FORECAST PERIOD...THE BOUNDARY IS EXPECTING TO
STALL ACROSS SE TX THRU C LA...YIELDING SHRA WITH INTERMITTENT
TSRA DURING THIS TIME.
DML
PREV DISCUSSION... /ISSUED 448 PM CDT SUN APR 15 2012/
SYNOPSIS...
WATER VAPOR AND UPPER AIR ANALYSIS SHOWS DEEP TROF LIFTING INTO
THE CNTL PLAINS. A SFC COLD FRONT ASSOCIATED WITH THIS SYSTEM
EXTENDED FM THE CNTL CONUS SOUTHWARD INTO TX...ALONG ROUGHLY A
PARIS TO GONZALES LINE. DIVERGENCE ALOFT IN CONJUNCTION WITH LOW
LEVEL FORCING ASSOCIATED WITH THE FRONT ARE PRODUCING AN
EXTENSIVE BAND OF SHOWERS AND THUNDERSTORMS FROM THE MID MS VALLEY
SOUTH INTO SE TX. RECENT RADAR TRENDS INDICATE SCT SHOWERS
DEVELOPING IN THE WARM MOIST AIRMASS ACRS SE TX INTO SW LA AHEAD
OF THIS LINE.
DISCUSSION...
THIS POTENT SYSTEM WILL CONTINUE TO MOVE EAST TONIGHT...BRINGING
THE COLD FRONT TO THE SABINE RIVER VALLEY BY EARLY MONDAY MORNING.
THERE IS STILL A SLIGHT RISK FOR SEVERE WEATHER ACRS SE TX INTO
WRN LA THIS EVENING...WITH AFTN HEATING CONTRIBUTING TO THE
DESTABILIZATION OF THE ATMOSPHERE. THE POTENTIAL FOR STRONG TO
SEVERE THUNDERSTORMS WILL SHIFT INTO CNTL AND SW LA AFTER
MIDNIGHT TONIGHT AS ADEQUATE DEEP LAYER SHEAR REMAINS IN PLACE
WITH INSTABILITY BECOMING MARGINAL. THE GREATEST THREAT WILL BE
DUE TO DAMAGING WINDS...ALTHOUGH HAIL AND ISOLATED TORNADOES
CANNOT BE RULED OUT ENTIRELY.
THE BIGGER CONCERN HOWEVER REMAINS THE POTENTIAL FOR HEAVY
RAINFALL TONIGHT INTO MONDAY. ABUNDANT MOISTURE OVER THE AREA WITH
PW VALUES APPROACHING 1.7 INCHES ON MONDAY WILL RESULT IN
EFFICIENT RAIN RATES IN SOME STORMS. THE SFC FRONT IS EXPECTED TO
STALL NR THE COAST OR OVER THE NRN GULF ON MONDAY...WITH AN
INVERTED TROF DEVELOPING ALONG IT MONDAY NIGHT. THIS WILL SERVE AS
A FOCUS FOR ADDITIONAL RAINFALL DEVELOPMENT MONDAY AFTN INTO
MONDAY NIGHT. AREAL RAINFALL TOTALS FROM TONIGHT THROUGH TUESDAY
WILL RANGE BETWEEN 2-4 INCHES...ALTHOUGH LOCALIZED HIGHER AMOUNTS
WILL BE POSSIBLE. AT THIS TIME...DO NOT SEE PRECIP TOTALS
EXCEEDING FLASH FLOOD GUIDANCE DURING THE PERIOD...ALTHOUGH
ISOLATED AREAS COULD APPROACH THESE VALUES SHOULD TRAINING STORMS
DEVELOP OVER THE AREA.
THE SFC LOW/FRONT WILL FINALLY SLIDE EAST TUESDAY AS THE UPPER
TROF AXIS CROSSES THE LOWER MS VALLEY. THIS WILL BRING DRIER AIR
INTO THE AREA. MORNING LOWS WILL BE MORE SEASONABLE WHILE AFTN HIGHS
WILL CLIMB INTO THE LOWER 80S. ANOTHER SYSTEM IS FCST TO MOVE
THROUGH THE AREA FRIDAY INTO SATURDAY...BRINGING ANOTHER CHANCE
FOR RAIN AND SLIGHTLY COOLER TEMPERATURES BY NEXT WEEKEND.
MARINE...
THE COMBINATION OF PERSISTENT HIGH PRESSURE TO OUR EAST AND
DEEPENING LOW PRESSURE OVER THE PLAINS STATES WILL KEEP A
STRONG ONSHORE FLOW OVER THE COASTAL WATERS. SMALL CRAFT ADVISORY
CONDITIONS WILL PERSIST OVER THE COASTAL WATERS THROUGH EARLY
MONDAY. SOUTHERLY WINDS WILL DIMINISH MONDAY MORNING AS A COLD
FRONT ADVANCES TOWARD THE REGION...WITH THE BOUNDARY ADVANCING
INTO THE WESTERN GULF MONDAY THEN BRIEFLY SLOWING OR STALLING.
NUMEROUS SHOWERS AND THUNDERSTORMS WILL ACCOMPANY THE FRONT FOR
THE BEGINNING OF THE WORK-WEEK. THE FRONT WILL FINALLY EXIT EAST
ON TUESDAY WITH OFFSHORE FLOW EXPECTED TUESDAY INTO WEDNESDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
KLCH 72 79 64 79 59 / 50 80 60 30 10
KBPT 71 79 66 80 61 / 60 80 50 30 10
KAEX 68 79 62 79 57 / 50 60 50 30 10
KLFT 72 82 65 79 60 / 30 70 60 50 20
&&
.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...SMALL CRAFT ADVISORY UNTIL 1 PM CDT MONDAY FOR THE FOLLOWING
ZONES: WATERS FROM INTRACOASTAL CITY TO CAMERON LA FROM 20
TO 60 NM...WATERS FROM CAMERON LA TO HIGH ISLAND TX FROM 20
TO 60 NM...WATERS FROM LOWER ATCHAFALAYA RIVER TO
INTRACOASTAL CITY LA FROM 20 TO 60 NM.
SMALL CRAFT ADVISORY UNTIL 1 AM CDT MONDAY FOR THE FOLLOWING
ZONES: COASTAL WATERS FROM CAMERON LA TO HIGH ISLAND TX OUT
20 NM...COASTAL WATERS FROM INTRACOASTAL CITY TO CAMERON LA
OUT 20 NM...COASTAL WATERS FROM LOWER ATCHAFALAYA RIVER TO
INTRACOASTAL CITY LA OUT 20 NM.
SMALL CRAFT EXERCISE CAUTION UNTIL 7 AM CDT MONDAY FOR THE
FOLLOWING ZONES: COASTAL WATERS FROM CAMERON LA TO HIGH
ISLAND TX OUT 20 NM...COASTAL WATERS FROM INTRACOASTAL CITY
TO CAMERON LA OUT 20 NM...COASTAL WATERS FROM LOWER
ATCHAFALAYA RIVER TO INTRACOASTAL CITY LA OUT 20 NM.
&&
$$
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
359 AM EDT MON APR 16 2012
.SYNOPSIS...
HIGH PRESSURE IS OFF THE SOUTHEAST COAST. A WEAKENING COLD FRONT
WILL APPROACH THE MID ATLANTIC TODAY...CROSSING THE REGION TONIGHT...AND
STALLING OVER THE CAROLINAS THROUGH MIDWEEK. AN UPPER DISTURBANCE WILL
MOVE THROUGH THE REGION TUESDAY NIGHT AND WEDNESDAY. HIGH
PRESSURE INFLUENCES THE MID-ATLANTIC STATES DURING THE SECOND HALF
OF THE WORK WEEK. LOW PRESSURE IS EXPECTED TO IMPACT THE REGION
THIS WEEKEND.
&&
.NEAR TERM /TODAY/...
VERY SUMMER-LIKE WX IS ON TAP FOR THE AREA TDA. 03Z SFC ANLYS
SHOWED A 1024 MB HIGH OFF THE SC CST...990 MB LOW PRES OVR SRN MN
W/ A WARM FNT XTNDG INTO ERN ONTARIO AND A COLD FNT W OF THE MS
RVR. THIS COMBINATION WL MEAN THAT THE MID ATLC WL XPRNC SSWRLY
FLOW TDA. GIVEN THE FACT THAT ALMOST THE ENTIRE AREA REACHED THE
M80S ON SUN (DMH AT 88 WAS THE HIGH POINT W/ HGR AT 79 THE LOW)
XPCT A NEAR REPEAT TDA. IR STLT DOES SHOW SOME CLD CVR OVR THE MID
ATLC...BUT THIS IS HIGH AND THIN AND SHOULDN`T DO MUCH TO SURPESS
HTG. HIGH TEMPS AGN GNRLY IN THE M80S.
&&
.SHORT TERM /TONIGHT/...
LN OF CNVCTN IN ASSO W/ THE CD FNT IS RATHER UNIFORM ATTM...AND
BOTH SREF AND HRRR SHOW CVRG IN THE LN WL BE WEAKENING AS IT
PROGRESSES TO THE E. AND THEN THERE IS THE ADAGE "WHEN IN DROUGHT
LV IT OUT." AREA IS CURRENTLY CLASSIFIED IN A D0/D1 DROUGHT. YES
THE RULE MAY BE SIMPLISTIC BUT IT IS SOMETHING TO CONSIDER...AND
IN SOME CASES IT APPLIES. WE ARE CARRYING CHC RW/TRW IN THE FAR
WRN SXNS THIS EVE...BUT IT IS DOUBTFUL THAT PCPN WL REACH FURTHER
E. A WIND SHIFT IS XPCTD LATE TNGT AS THE WEAKENING FNT CROSSES
THE RGN..W/ TEMPS SHOWING A LTL MORE DOWNWARD MVMNT LATE...BUT
GIVEN THE WARMTH OF THE PRVS TWO DAYS WL KEEP FCSTD MINS ABV GDNC
RANGING FM THE M40S IN THE HIGHLANDS TO THE LM60S I-95 AND E.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
THE COLD FRONT WILL MOVE AWAY FROM THE EAST COAST TUE MRNG. IN WAKE
OF THE COLD FRONT...BREEZY W-NW FLOW WILL ADVECT COOLER AND DRIER
AIR INTO THE MID-ATLANTIC STATES AS HIPRES BUILDS IN FROM THE GREAT
LAKES AND OH VLY. WARMING FROM DOWNSLOPING FLOW AND SUNSHINE WILL
OFFSET CAA TO SOME DEGREE EAST OF THE BLUE RIDGE. MAX TEMPS TUE WILL
RANGE FROM AROUND 60F ALONG THE ALLEGHENY FRONT TO MID 70S ALONG AND
EAST OF I-95.
SRN-STREAM SHORTWAVE TROUGH WILL TRACK FROM THE SRN/CENTRAL MS VLY
TO THE MID-ATLANTIC STATES TUE NGT AND WED. SLY FLOW OUT AHEAD OF
THE TROUGH WILL PROMOTE ISENTROPIC LIFT ALONG A FRONTAL BOUNDARY
THAT PUSHES NWD INTO SRN VA ON WED. WITH THE FRONTAL BOUNDARY
EXPECTED TO REMAIN SOUTH OF THE CWA...WEAKENING ULVL JET DYNAMICS
AND A DRY BOUNDARY LAYER IN PLACE...HAVE TRENDED TOWARD A DRIER
SOLUTION THAN THE PREV FCST. ANY SHOWERS WED WILL BE LGT AND MAINLY
FROM CENTRAL VA/SRN MD-SWD.
THE UPPER SHORTWAVE TROUGH WILL MOVE OFF THE MID-ATLANTIC COAST WED
NGT. SFC HIPRES/ZONAL FLOW DOMINATES THE AREA THU. FLOW BECOMES MORE
SLY FRI AS HIPRES SHIFTS OFF THE COAST AND AN UPPER TROUGH AMPLIFIES
OVER THE MIDWEST. ALTHOUGH AN ISO SHOWER CANNOT BE RULED OUT WEST OF
THE BLUE RIDGE FRI AS SLY FLOW DRAWS MOISTURE NWD OUT AHEAD OF THE
NEXT STORM SYSTEM...MAINLY DRY CONDITIONS IN STORE FOR THE SECOND
HALF OF THE WORK WEEK.
COMPLEX WX PATTERN THIS WEEKEND AS THE UPPER TROUGH AMPLIFIES
OVER THE ERN CONUS IN RESPONSE TO A STRONG DISTURBANCE THAT DIGS ON
THE BACKSIDE OF THE TROUGH. CHANCES FOR SHOWERS AND STORMS INCREASE
SAT AS A DEEP MOISTURE CONNECTION FROM THE GULF OF MEXICO TO THE
MID-ATLANTIC REGION EXISTS AHEAD OF A COLD FRONT. MOST EXTENDED-
RANGE GUIDANCE FCST THE DEVELOPMENT OF A CLOSED LOW ALONG THE ERN
SEABOARD LATE IN THE WEEKEND. THERE IS A LOT OF UNCERTAINTY
REGARDING THE DEVELOPMENT OF A COASTAL LOW AND ITS POTENTIAL IMPACTS
TO THE REGION. EYES WILL BE ON THIS SYSTEM AS IT MAY BRING A NEEDED
CHANCE FOR RAIN.
&&
.AVIATION /07Z MONDAY THROUGH FRIDAY/...
VFR CONDS FCSTD AT ALL AIRPORT SITES TDA/TNGT.
BREEZY W-NW FLOW BEHIND A COLD FRONT TUE. A PROLONGED PERIOD OF VFR
CONDITIONS EXPECTED TUE-FRI. ONLY WRINKLE IN A DRY FCST WILL BE A
CHANCE OF SHOWERS WED AT CHO.
&&
.MARINE...
THE COMBO OF HIGH PRES OFFSHORE/CD FNT IN THE MS VLLY AND SRLY
CHANNELING HV CAUSED WIND GUSTS ARND 20 KT OVRNGT ON THEBAY. THIS
IS XPCTD TO CONT THIS MRNG/TNGT...AND ACROSS ALL THE WATERS DURG
MONDAY. SCA IN EFFECT FOR THESE AREAS. A WK FNT WL PUSH INTO THE
WATERS LATE TNGT. NO PCPN IS XPCTD W/ IT.
SCA HAS BEEN EXTENDED INTO TUE MRNG FOR THE CHSPK BAY SOUTH OF
POOLES ISLAND AND THE LOWER TIDAL POTOMAC RVR AS NW FLOW BEHIND A
COLD FRONT GUSTS TO 20 KT. SCA MAY NEED TO BE EXTENDED INTO TUE
AFTN...BUT CONFIDENCE WAS NOT HIGH ENOUGH TO DO SO ATTM. WINDS ARE
EXPECTED TO REMAIN BELOW SCA LVLS TUE NGT THRU THE REST OF THE WORK
WEEK.
&&
.FIRE WEATHER...
2 MAJOR FIRES PERSIST IN OUR CWA - "WOLF GAP" ALONG THE BORDER OF
HARDY AND SHENANDOAH COUNTIES..AND "SHIPWRECK" S OF MASSANUTTEN MTN.
MOISTURE LVLS HV CREPT UP...AND MID AFTN RH WL BE IN THE MU30S W
OF THE BLUE RDG. THIS IS ABV THE RH VALUES NEEDED FOR
CONSIDERATION OF A RED FLAG WRNG. WINDS OF 20-25 MPH PSBL LATE
THIS MRNG AND AFTN. 10 HR FUEL MOISTURES ARE ON THE CUSP OF RED
FLAG CONSIDERATION. AM NOT PLANNING TO ISSUE ANY TYPE OF SPL
PRODUCT - WL LV IT FOR THE DAYSHIFT TO CONTACT STATE FIRE MGRS AND
LET THEM TAKE IT FM THERE.
&&
.COMMUNICATION...
NWR XTMR WNG-736 IS CURRENTLY OFF THE AIR. TELCO HAS BEEN NOTIFIED.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL NOON EDT TUESDAY FOR ANZ531>534-537-
539>541-543.
SMALL CRAFT ADVISORY FROM 8 AM THIS MORNING TO 8 PM EDT THIS
EVENING FOR ANZ530-535-536-538-542.
&&
$$
PRODUCTS...WOODY!/JRK
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
204 AM EDT MON APR 16 2012
.SYNOPSIS...
ISSUED AT 355 PM EDT SUN APR 15 2012
A STRONG COLD FRONT WILL CROSS SOUTHWEST LOWER MICHIGAN OVERNIGHT.
IT WILL ACCOMPANIED BY A LINE OF THUNDERSTORMS WITH GUSTY WINDS.
TEMPERATURES WILL FALL DURING MONDAY WITH GUSTY WINDS. EARLY MORNING
SHOWERS AND THUNDERSTORMS WILL GIVE WAY TO SCATTERED AFTERNOON
SHOWERS. THOSE COULD BE MIXED WITH WET SNOW OVER NORTHWEST
SECTIONS BY LATE AFTERNOON. SPRINKLES AND FLURRIES WILL END MONDAY
NIGHT AND THAT WILL LEAD TO CLEARING SKIES WITH FROST AND FREEZING
TEMPERATURES. A QUICK MOVING SYSTEM WILL BRING MORE SHOWERS TO THE
AREA WEDNESDAY.
&&
.UPDATE...
ISSUED AT 205 AM EDT MON APR 16 2012
WE HAVE ISSUED A WIND ADVISORY FOR THE ENTIRE CWFA VALID BEGINNING
IMMEDIATELY THROUGH 02Z TONIGHT. LLJ RESPONSIBLE FOR THE SHOWERS
AND STORMS LAST EVENING AND EARLY THIS MORNING IS NOW ALMOST
OVERHEAD. ALMOST ALL OF THE WIND THUS FAR HAS REMAINED
ALOFT DUE TO THE WAA...EVEN WITH SOME CONVECTION IN THE AREA. HOWEVER
ALONG AND BEHIND THE FRONT WHERE CAA IS NOW BEGINNING...BETTER
MIXING IS TAKING PLACE. THIS IS RESULTING IN NON-CONVECTIVE WIND
GUSTS OF 40 TO 55 MPH ACROSS THE LAKE OVER WISCONSIN. THESE WINDS
ARE STARTING TO SHOW UP AT KMKG AND KLDM WITH GUSTS UP TO 38 KNOTS
IN THE LAST HOUR.
WE EXPECT SOME OF THIS WIND TO AFFECT THE AREA THIS MORNING. THE
STRONGEST WIND WILL COME BEGINNING AROUND MID MORNING...AND LIKELY
LAST THROUGH EARLY EVENING WITH CAA AND DIURNAL MIXING. MOS WINDS ARE
QUITE IMPRESSIVE WITH SOME SUSTAINED 30 SHOWING UP THIS AFTERNOON.
UPDATE ISSUED AT 1055 PM EDT SUN APR 15 2012
WE HAVE ISSUED AN UPDATE THIS EVENING...MAINLY TO BUMP POPS UP TO
THE 90-100 PCT CATEGORY. AXIS OF BEST MOISTURE AHEAD OF THE FRONT IS
NOW LEANING INTO THE AREA FROM THE WEST. MOST LOCATIONS WILL GET
MEASURABLE PCPN BASED OFF OF THE COVERAGE OF PCPN TO OUR SOUTH
AND WEST. THIS ALL OCCURS AS THE STRONG LLJ AHEAD OF THE SYSTEM
WILL FEED STRONG MOISTURE TRANSPORT INTO THE AREA.
SEVERE THREAT IS QUITE LIMITED MAINLY DUE TO THE LACK OF SFC/ML BASED
INSTABILITY WE WERE UNABLE TO GENERATE OVER THE AREA TODAY WITH
PLENTY OF CLOUD COVER. THAT SAID...WE CAN NOT RULE OUT SOME
ISOLATED HAIL APPROACHING SEVERE LIMITS BASED ON STORMS EARLIER
NEAR CHICAGO. LOCAL WIND GUSTS CAN NOT BE RULED OUT EITHER WITH
THE STRONG WIND FIELDS OVERHEAD.
&&
.SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT)
ISSUED AT 355 PM EDT SUN APR 15 2012
THERE ARE SEVERAL ISSUES TO DEAL WITH DURING THE SHORT TERM PART
OF THE FORECAST. FIRST IS HOW STRONG WILL THE LINE OF THUNDERSTORMS
WITH THE COLD FRONT BE? THEN THERE IS THE ISSUE OF DO WE NEED A
WIND ADVISORY MONDAY AS THE COLD AIR COMES IN BEHIND THE COLD
FRONT. FINALLY THERE IS THE ISSUE OF A FREEZE MONDAY NIGHT.
AS FOR THE CONVECTION WITH THE COLD FRONT... OUR STORY REMAINS
UNCHANGED. THEN NAM 12Z... RUC 18Z ...GFS 12Z... AND ECMWF 12Z ALL
SHOW A 60 TO 70 KNOT LOW LEVEL JET COMING ON SHORE AROUND 2 AM THEN
REACHING EASTERN LOWER MICHIGAN BY 8 AM MONDAY. SINCE AT 18Z AND
19Z THE THUNDERSTORMS AREA WHERE THEY ARE SUPPOSE TO BE ON THE LEFT
SIDE OF THE LOW LEVEL JET... THAT MEANS THE MAIN LINE OF STORMS
WILL CROSS OUR CWA AROUND TO AFTER MIDNIGHT. WHAT HELPS TO KEEP
THE STORMS FROM GOING SEVERE OVER OUR CWA THROUGH IS THE JET CORE
AT 300 MB IS CURRENTLY SOUTHWEST OF MICHIGAN AND WILL NOT BE WEST
OF MICHIGAN UNTIL 2 AM. THAT MEANS THIS AREA WILL BE IN THE RIGHT
EXIT REGION OF THE UPPER JET CORE. THAT IS NOT CONDUCIVE TO SEVERE
STORMS. THE MOST UNSTABLE CAPE IN THE 950 TO 850 LAYER IS OVER
1500 J/KG OVER WI THIS EVENING BUT LESS THEN 400 J/KG OVER MI WHEN
THE LINE IS EXPECTED TO GET HERE. SO MY SPIN IS WE WILL SEE A
WEAKENING LINE OF STORMS COME INTO SOUTHWEST LOWER MICHIGAN AROUND
MIDNIGHT. THE LINE WILL WEAKEN AS IT CROSS THE CWA LATE TONIGHT.
ANY SEVERE WINDS WILL BE NEAR THE LAKE MICHIGAN SHORE AS THE
STORMS COME DOWN OFF THE MAINE LAYER.
THE DRY SLOT MOVES IN MID DAY MONDAY. SOUTHWEST MICHIGAN IS IN THE
DRY SLOT AND THERE IS 50 KNOTS IN THE MIXED LAYER AS THIS MOVES
ACROSS THE CWA. THIS WILL BRING OUR GUSTS CLOSE TO ADVISORY
CRITERIA WINDS BUT AT THIS POINT WE FEEL THIS IS OVER DONE BY THE
NAM SO WE WILL STAY JUST BELOW ADVISORY GUSTS.
WRAP AROUND MOISTURE MOVES IN DURING THE AFTERNOON SO SCATTERED
SHOWERS WILL MOVE INTO THE CWA BY EARLY TO MID AFTERNOON. THE AIR
BECOMES COLD ENOUGH FOR SNOW OVER THE NW CWA BY LATE AFTERNOON AND
OVER THE REST OF THE CWA BY MID EVENING. SO WE COULD SEE A FEW
SNOW FLAKES MONDAY EVENING. ENOUGH DRY AIR MOVES IN BEHIND THE
SYSTEM AFTER MIDNIGHT TO CLEAR THE SKIES AND THIS LEAD TO FROST
AND FREEZING TEMPERATURES. WE WILL LIKELY NEED A FREEZE WARNING
FOR TUESDAY MORNING.
$$
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 355 PM EDT SUN APR 15 2012
COOL AND DRY HIGH PRESSURE WILL BE SETTLING OVER THE REGION FOR
THE START OF LONG TERM. TUESDAY NIGHT COULD SEE MORE FROST WITH
TEMPS DIPPING TO AROUND 30 OVER THE INTERIOR NORTH...AND UPPER 30S
OVER THE SOUTHERN NEAR SHORE.
HAVE PUSHED THE POPS BACK A BIT ON WED. LOOKS LIKE ANY PCPN WILL
HOLD OFF UNTIL WED AFTERNOON...AND MAYBE NOT UNTIL AFTER NIGHTFALL
IN THE EAST. ANOTHER RATHER WOUND-UP NORTHERN STREAM SYSTEM WILL BE
MOVING ALONG THE U.S./CANADIAN BORDER...DRAGGING A COLD FRONT
THROUGH LOWER MICHIGAN WED NIGHT. AFTER A BRIEF BREAK FROM THE PCPN
ON THURSDAY...THE FRONT WILL STALL TO OUR SOUTH WITH A WAVE OF LOW
PRESSURE TRACKING ALONG IT. NOT GOOD AGREEMENT IN THE MODELS WITH
THE POSITION OF THIS LOW WITH THE EURO MUCH FURTHER NORTH THAN THE
GFS. THIS IS CAUSED BY THE FURTHER NORTHERLY POSITION OF THE
BAROCLINIC ZONE ON THE EURO. LOOKS LIKE THE HIGH OVER SOUTHERN
CANADA WILL BE THE DECIDER...IF THIS PROVES TO BE STRONGER THE PCPN
WILL STAY SOUTH. WILL SEE HOW THIS PANS OUT...FOR NOW HAVE
CONTINUED THE CHC POPS...HIGHEST SOUTH FOR THURSDAY NIGHT AND FRIDAY.
EVEN THE EURO EXITS ANY LINGER PCPN BY FRIDAY NIGHT. NEXT WEEKEND
LOOKS DRY WITH HIGH PRESSURE SLOWLY BUILDING IN. HOWEVER...IT DOES
APPEAR TO REMAIN COOL WITH MAX TEMPS MAINLY 50 TO 55...AND MAYBE
HOLDING IN THE 40S ALONG THE LAKESHORE.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 205 AM EDT MON APR 16 2012
MAIN CONCERNS WITH THE 06Z SET OF FCSTS WILL BE PCPN TRENDS
THROUGH THIS EVENING...AND WIND TRENDS.
STORMS HAVE MOVED THROUGH THE AREA LAST EVENING AND EARLY THIS
MORNING....AND HAVE WEAKENED. SOME LIGHT RAIN REMAINS OVER THE
AREA...JUST OUT AHEAD OF THE INCOMING COLD FRONT THAT WILL MOVE
THROUGH IN THE NEXT FEW HOURS FROM WEST TO EAST. RAINFALL WILL
TEMPORARILY END WITH THE FRONTAL PASSAGE. BEHIND THE FRONTAL
PASSAGE...WINDS ARE INCREASING SIGNIFICANTLY OUT OF THE SOUTH.
WINDS GUSTS OF 38 TO 35 KNOTS HAVE BEEN OBSERVED AT KMKG AND KLDM
RESPECTIVELY.
ONCE THE WINDS COME UP BEHIND THE FRONT THIS MORNING...THEY WILL
REMAIN UP INTO THIS EVENING. WE ARE EXPECTING TO SEE GUSTS PEAK
AROUND 40 KNOTS THIS AFTERNOON WITH DAYTIME HEATING AND COLDER AIR
COMING IN. SHOWERS WILL ONCE AGAIN BE POSSIBLE THIS AFTERNOON AS
THE WRAP AROUND MOISTURE ROTATES IN. THE SHOWERS WILL REMAIN
POSSIBLE INTO THIS EVENING BEFORE THEY WILL END AND SKIES WILL
CLEAR. WINDS WILL ALSO DIMINISH BELOW 20 KNOTS AT THAT TIME.
&&
.MARINE...
ISSUED AT 205 AM EDT MON APR 16 2012
WE HAVE GONE AHEAD AND PUSHED UP THE TIMING OF THE GALE WARNING TO
THE CURRENT TIME. THE STRONG WINDS ACROSS WISCONSIN ARE NOW BEING
OBSERVED ON THIS SIDE OF THE LAKE. GALES WILL CONTINUE TO BE
EXPECTED THROUGH EARLY THIS EVENING BEFORE DIMINISHING.
&&
.HYDROLOGY...
ISSUED AT 355 PM EDT SUN APR 15 2012
THERE WAS BETWEEN A HALF INCH AND TWO INCHES OF RAIN EARLY THIS
MORNING OVER MOST OF THE CWA. THE USGS PAGE SHOWS RIVER AND STREAM
LEVELS NEAR AND SOUTH OF I-96 ROSE SHARPLY THIS MORNING BUT REMAIN
WILL BELOW NORMAL NORTH OF I-96. THE RAINFALL THIS EVENING SHOULD
BE LESS THAN A HALF INCH AND HAVE LITTLE IMPACT ON STREAM LEVELS.
ONLY SYCAMORE CREEK NEAR HOLT IS FORECAST TO RISE TO NEAR ADVISORY
STAGE. WE WILL CONTINUE TO MONITOR THIS. THE BOTTOM LINE IS WE DO
NOT AT THIS POINT SEE MAJOR FLOODING ISSUES AT THIS TIME.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WIND ADVISORY UNTIL 10 PM EDT THIS EVENING FOR MIZ037>040-
043>046-050>052-056>059-064>067-071>074.
LM...GALE WARNING UNTIL 10 PM EDT THIS EVENING FOR LMZ844>849.
&&
$$
UPDATE...NJJ
SYNOPSIS...WDM
SHORT TERM...WDM
LONG TERM...JK
AVIATION...NJJ
HYDROLOGY...WDM
MARINE...NJJ
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
126 AM EDT MON APR 16 2012
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 446 PM EDT SUN APR 15 2012
SHORT TERM FCST HAS BEEN A CHALLENGE TODAY WITH IMPORTANT DETAILS TO
CAPTURE IN THE GRIDS WITH NEARLY ALL FCST ELEMENTS... INCLUDING
SIGNIFICANT NON-DIURNAL TEMPS TRENDS...GALES ON THE LAKE/POSSIBLE
ADVY WINDS INLAND...POSSIBLE SVR TSRA TONIGHT...AND MIX PCPN ISSUES
MON.
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A VIGOROUS SHORTWAVE
LIFTING NE THRU THE WRN PLAINS. SFC LOW IS OVER NE NEBRASKA WITH SFC
WARM FRONT EXTENDING NE TO NEAR KMSP THAN E TO JUST N OF KGRB. FRONT
HAS MADE LITTLE PROGRESS OVER THE LAST FEW HRS...AND SO FAR...THERE
HASN`T BEEN MUCH SHRA ACTIVITY N OF THE FRONT. STRONGER LOW-MIDLEVEL
FRONTOGENESIS IS SUPPORTING BEST SHRA DEVELOPMENT TO THE W IN NE
MN/WRN LAKE SUPERIOR. HOWEVER...WITH MODELS INDICATING MOISTURE
TRANSPORT BECOMING FOCUSED TOWARD UPPER MI OVER THE NEXT FEW HRS...
SHRA SHOULD EXPAND OVER THE FCST AREA. WITH ELEVATED CAPE ALSO
INCREASING...ISOLD/SCT TSRA SHOULD ALSO DEVELOP. SVR THREAT IS
UNCERTAIN TONIGHT DUE TO UNCERTAINTY IN PROGRESS OF WARM FRONT. IF
FRONT LINGERS TO S THIS EVENING AND ELEVATED STORMS DO DEVELOP...
EFFECTIVE SHEAR WILL SUPPORT ORGANIZED UPDRAFTS AND A HAIL
POTENTIAL...ESPECIALLY OVER THE SCNTRL. IF WARM FRONT LIFTS N THRU
CNTRL/ERN UPPER MI...THERE MAY NOT BE MUCH ACTIVITY UNTIL COLD FRONT
ARRIVES LATE TONIGHT WHEN INSTABILITY WILL BE DIMINISHING. AT THIS
POINT...ELEVATED SVR STORMS APPEAR THE MORE LIKELY SCENARIO IF
STORMS CAN ORGANIZE N OF SLOW MOVING WARM FRONT. TEMPS TONIGHT WILL
ALSO BE HIGHLY DEPENDENT ON WARM FRONT LOCATION. TEMPS MAY RISE
ACROSS THE CNTRL/E WHILE A CHILLY E WIND KEEPS READINGS OVER THE
KEWEENAW IN THE LWR 40S. FOG MAY BE DENSE AT TIMES WHERE FLOW IS
UPSLOPE OFF LAKE SUPERIOR AND LAKE MICHIGAN.
SFC LOW WILL TRACK ACROSS CNTRL UPPER MI/SE LAKE SUPERIOR LATE
TONIGHT/MON MORNING. SHARP/STRONG CAA MON WILL BRING A QUICK DROP IN
TEMPS FROM NW TO SE AFTER COLD FROPA. FCST SOUNDINGS SUGGEST AT
LEAST SOME POTENTIAL FOR A BRIEF PERIOD OF SLEET BTWN THE TRANSITION
FROM RAIN TO SNOW. LOW-LEVEL TEMPS ALSO APPEAR TO FALL ENOUGH FOR
SOME LAKE ENHANCEMENT IN THE DEFORMATION PCPN AREA SWINGING ACROSS
UPPER MI MON. RIGHT NOW...EXPECT 1 TO 2 INCHES OF SNOW MON OVER THE
W AND NCNTRL. HIGH TERRAIN OF THE FAR W MAY SEE UP TO 3 INCHES.
COULD BE A SNOW ADVY EVENT IF DEFORMATION PCPN SHIELD BECOMES WELL
ORGANIZED TO THE W TONIGHT. AS FOR WINDS...SHARP CAA WILL ENHANCE
LOW-LEVEL MIXING...AND WITH 40-45KT AVBL IN THE MIXED LAYER...ADVY
LEVEL WINDS ARE A GOOD BET NEAR LAKE SUPERIOR MON...ESPECIALLY
KEWEENAW COUNTY BEGINNING IN THE MORNING AND FROM KMQT EASTWARD IN
THE AFTN. ISALLOBARIC COMPONENT TO THE WIND ROUGHLY 90 DEGREES TO
THE GRADIENT WIND SHOULD KEEP THIS FROM BEING A HIGHER END WIND
EVENT. TEMPS WILL FALL FROM NW TO SE THRU THE DAY...THOUGH THERE
WILL BE SOME WARMING OVER THE E MON MORNING PRIOR TO COLD FROPA.
TEMPS IN THE AFTN WILL PROBABLY BE AT OR BELOW FREEZING OVER THE W
AND NCNTRL.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 446 PM EDT SUN APR 15 2012
NO SIGNIFICANT CHANGES TO UPPER PATTERN DEPICTION SHOWN BY MEDIUM
RANGE MODELS YDY WITH NEGATIVE ANAMOLIES STATIONED OVER NORTHEAST
PACIFIC OCEAN/GULF OF ALASKA AND OVR HUDSON BAY INTO NUNAVUT CANADA.
ZONAL FLOW DOMINATES CONUS MUCH OF THE WEEK AND REALLY INTO NEXT
WEEKEND AS WELL. ATTM ONLY ONE SYSTEM WILL IMPACT THE AREA IN THE
LONGER TERM...BUT THAT MAY CHANGE DEPENDING ON TRACK OF LATE WEEK
SYSTEM.
BLAST OF WINTRY WEATHER GRADUALLY DIMINISHES ON MONDAY NIGHT. PLENTY
OF 925-850MB MOISTURE...CYCLONIC SFC-H85 FLOW...AND 900 TEMPS AROUND
-10C SO PREFER TO LET SNOW SHOWERS LINGER ALONG LK SUPERIOR INTO THE
OVERNIGHT HOURS FOR AREAS FAVORED BY NW WINDS. ADDITIONAL SNOW
ACCUMS MONDAY NIGHT WILL STILL BE MINIMAL. MAIN ISSUE WILL BE GUSTY
NORTH-NORTHWEST WINDS UP TO 45 MPH ALONG LK SUPERIOR ALONG WITH THE
SNOW SHOWERS. ARRIVAL OF LOW-LEVEL RIDGE DIMINISHES SNOW SHOWERS
TOWARD MORNING OVER EASTERN CWA. SFC RIDGE AND EDGE OF THERMAL TROUGH
RESULTS IN LIGHT WINDS/COOL CONDITIONS ON TUESDAY. COOLEST READINGS
AROUND 40 DEGREES ALONG LK SUPERIOR WITH NE WINDS.
SHORTWAVE ON SOUTHERN EDGE OF TROUGH OVR GULF OF ALASKA FCST TO
SLIDE ACROSS ROCKIES INTO NORTHERN PLAINS BY TUESDAY NIGHT AND PUSH
ACROSS UPPER GREAT LAKES ON WEDNESDAY. SW WINDS AHEAD OF SFC-H85
TROUGH HELP TO BRING MUCH WARMER AIR INTO UPR LAKES IN WAKE OF EARLY
WEEK CHILL AND INCREASING MOISTURE AS WELL. JET STREAKS SLIDING
ACROSS THE NORTHERN PLAINS AND OVR ONTARIO SHOULD HELP SYSTEM STAY
FAIRLY ORGANIZED AS IT CROSSES CWA ON WEDNESDAY. MSLP FCSTS DEPICT
THIS AS WELL WITH PRESSURES STEADY OR EVEN SLOWLY FALLING FM TUESDAY
NIGHT INTO WEDNESDAY ACROSS UPPER LAKES. GIVEN OVERALL DRY PATTERN
WE ARE IN CANNOT GET TOO EXCITED ABOUT SIGNIFICANT PRECIPITATION
WITH THE SYSTEM...BUT TOTAL LIQUID COULD CHECK IN AROUND 0.25 INCH
IN SOME AREAS. PTYPE MAY BE ISSUE INITIALLY LATE TUESDAY NIGHT OVER
THE WEST AS SHALLOW COLD AIR HANGS TOUGH IN WAKE OF COLD PUSH EARLY
IN THE WEEK. LATEST MODEL RUNS INDICATE POTENTIAL FOR FROZEN PRECIP
IS NOT AS HIGH AS BEFORE AS SOUTH WINDS ADVECT WELL ABOVE FREEZING
DWPNTS INTO UPR MI BY DAYBREAK WEDNESDAY. OVERALL...MAY BE SOME SNOW
OR PERHAPS FREEZING RAIN...BUT AS IT STANDS NOW IT WOULD BE PRETTY
SHORT LIVED. SOME POTENTIAL SOME SNOW AS SYSTEM EXITS ON WEDNESDAY
NIGHT. 850MB/925MB TEMPS AS LOW AS -10C/-6C WOULD EVEN OPEN DOOR TO
BRIEF LAKE ENHANCED SNOW OVR HIGHER TERRAIN OF WEST GIVEN ENOUGH
MOISTURE REMAINS AS COLDER AIR WORKS INTO UPR LAKES REGION.
IN THE EXTENDED...FRIDAY SYSTEM THAT ECMWF HAS BEEN SHOWING OFF AND
ON THE LAST FEW DAYS WAS OFF ON THE 00Z RUN BUT IS KIND OF BACK ON
AGAIN WITH THE 12Z RUN...THOUGH BULK OF HEAVIER QPF REMAINS SOUTH OF
UPR MI. GFS IS MUCH FARTHER SOUTH. SOUTHERN TRACK DOES MAKE SOME
SENSE AS PRIMARY FRONTAL BOUNDARY IS FCST TO SETTLE INTO THE
NORTHERN PORTIONS OF THE OHIO VALLEY IN WAKE OF THE WEDNESDAY SYSTEM
AND SINCE BETTER CHANCE OF CYCLOGENESIS WOULD BE ALONG THE BETTER
SFC TEMPERATURE GRADIENT. SYSTEM IS STILL NEAR THE ALLUTIANS IN THE
PACIFIC SO THERE LIKELY WILL BE SOME JUMPING AROUND ON THE POSITION
OF THE LOW YET THIS WEEK. FOR NOW THOUGH...POPS WILL STAY ON THE LOW
SIDE FOR THIS SYSTEM WITH THE HIGHER POPS OVER THE SOUTHERN CWA
THURSDAY NIGHT AND FRIDAY. ECMWF IDEA FM 12Z/14 APRIL AND 12Z THIS
MORNING WOULD INDICATE SIGNIFICANT SNOW OVR PORTIONS OF UPR LAKES
INCLUDING UPR MI.
BEYOND FRIDAY APPEARS DRY WEATHER IS IN STORE FOR NEXT WEEKEND. WILL
NOT BE ESPECIALLY WARM THOUGH AS LARGER SCALE TROUGH RESIDES OVR
MUCH OF EASTERN CANADA AND EASTERN CONUS. MODELS SHOW ANOTHER WAVE
DIVING IN FM THE PACIFIC TROUGH BUT WITH EXPECTED AMPLITUDE OF
TROUGH THIS SYSTEM WILL PROBABLY STAY TO THE SOUTH OF UPR LAKES AS
THE LATE WEEK ONE DOES. SFC-H85 RIDGE WILL BE OVERHEAD LEADING TO
LIGHT WINDS/LK BREEZES. BEST CHANCE FOR DAYTIME TEMPS AT LEAST NEAR
NORMAL WILL BE WELL INLAND FM THE LAKES TOWARD WISCONSIN BORDER.
COULD ALSO BE CHILLY NIGHTS AS WELL...WITH TEMPS POSSIBLY IN THE
TEENS AND 20S. RELATIVE HUMIDITIES LIKELY WILL BE ON THE LOW SIDE
FOR THE WEEKEND AS WELL.
APPEARS PATTERN BEGINS TO CHANGE DAYS 8-10 OR STARTING ON 24 APRIL
AS STRONG RIDGE BUILDS FM CNTRL CONUS INTO WESTERN GREAT LAKES.
GIVEN LACK OF RAINFALL THIS MONTH AND SINCE WE ARE STILL NOT
COMPLETELY GREENED UP OVR UPR MI...THE WARMER AND DRY WEATHER WILL
PROBABLY LEAD TO INCREASING FIRE WEATHER ISSUES. PLENTY OF TIME TO
DIAGNOSE THIS THOUGH.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 126 AM EDT MON APR 16 2012
FORECAST OVER THE NEXT 24 HOURS IS FAIRLY COMPLEX WITH A LOW
PRESSURE SYSTEM AND WARM FRONT SHIFTING NORTHEASTWARD THROUGH MUCH
OF THE UPPER PENINSULA.
KIWD AND KCMX...CONDITIONS WILL REMAIN NEAR ALT LANDING MINS THROUGH
AT LEAST LATE MORNING AS FLOW BCMS ONSHORE AND NERLY. COLD ADVECTION
BEHIND FRONT WILL TURN SHRA TO SHSH BY LATE MORNING AS NORTH WINDS
GUSTS FM 30-35 KT. EXPECT CONDITIONS TO IMPROVE TO MVFR BY LATE MON
AFTERNOON AS RDG BUILDING IN WILL KNOCK DOWN WINDS AND BRING IN
DRIER AIR. STEEP LOW-LVL LAPSE RATES WILL KEEP MVFR CLOUDS INTACT
HOWEVER. INCLUDED TS VCNTY AT KIWD IN THE FIRST COUPLE OVERNIGHT
HRS.
KSAW...EXPECT CONDITIONS TO IMPROVE TO MVFR THROUGH THE EARLY
MORNING WITH WARMING AND MIXING AHEAD OF THE FRONTAL SYSTEM. WINDS
WILL SHIFT NW AND BCM GUSTY AOA 30 KT BEHIND COLD FRONT WITH SHRA
CHANGING TO SHSN ALTHOUGH EXPECT GENERALLY MVFR CONDITIONS. RDGG FM
THE WEST WILL DIE DOWN WINDS TOWARD MON EVENING AS LAKE ENHANCED
SNOW ENDS. MVFR CLOUDS WILL REMAIN THROUGH 06Z TUE.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 446 PM EDT SUN APR 15 2012
SFC LOW TRACKING FROM NE NEBRASKA TO UPPER MI/SE LAKE SUPERIOR
TONIGHT/MON MORNING WILL BRING A NE TO N GALE EVENT TO LAKE SUPERIOR
TONIGHT AND MON. GALES HAVE BEEN A LITTLE SLOW TO DEVELOP OVER THE
FAR W THIS AFTN...BUT WINDS SHOULD QUICKLY RAMP UP OVER THE NEXT FEW
HRS AS PRES FALLS INCREASE IN MAGNITUDE TO THE SW OF THE LAKE AHEAD
OF THE APPROACHING SFC LOW. AS THE LOW SHIFTS ACROSS UPPER MI/SE
LAKE SUPERIOR AND THEN E MON...NE WINDS WILL BACK N WITH GALES
QUICKLY EXPANDING E ACROSS THE LAKE. SHARP CAA/STRONG LOW-LEVEL
INSTABILITY WILL SUPPORT FREQUENT HIGH END GALE GUSTS. WINDS WILL
DIMINISH TO UNDER 20KT FROM W TO E MON NIGHT/EARLY TUE AS HIGH PRES
RIDGE BUILDS SE TO THE UPPER LAKES. LIGHTER WINDS WILL PERSIST THRU
TUE AFTN. NEXT LOW PRES SYSTEM MOVING THRU THE UPPER LAKES WED WILL
BRING ANOTHER PERIOD OF 15-25KT WINDS WED/THU...WITH THE STRONGER
WINDS AFFECTING MAINLY THE E HALF OF THE LAKE.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
GALE WARNING FROM 5 PM THIS AFTERNOON TO 2 AM EDT TUESDAY FOR
LSZ251-267.
GALE WARNING FROM 11 AM THIS MORNING TO 2 AM EDT TUESDAY FOR
LSZ266.
GALE WARNING UNTIL 2 PM EDT /1 PM CDT/ THIS AFTERNOON FOR LSZ162.
GALE WARNING UNTIL 8 PM EDT THIS EVENING FOR LSZ242>244-263-264.
GALE WARNING FROM 11 AM THIS MORNING TO 8 PM EDT THIS EVENING
FOR LSZ265.
GALE WARNING FROM 2 PM THIS AFTERNOON TO 2 AM EDT TUESDAY FOR
LSZ249-250.
GALE WARNING FROM 2 PM THIS AFTERNOON TO 8 PM EDT THIS EVENING
FOR LSZ248.
GALE WARNING FROM 5 AM EARLY THIS MORNING TO 8 PM EDT THIS
EVENING FOR LSZ245.
GALE WARNING UNTIL 11 AM EDT /10 AM CDT/ THIS MORNING FOR LSZ240-
241.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...JLA
AVIATION...VOSS
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
352 AM CDT MON APR 16 2012
.DISCUSSION...
MID/UPPER LEVEL CIRCULATION WILL CONTINUE TO CAUSE LIGHT PRECIP
OVER EASTERN AREAS THIS MORNING WITH LATEST RUC PICKING UP ON A
SSW-NNE BAND OF FGEN..PRIMARILY OVER EAST CENTRAL MN BUT THEN
WEAKENING WITH TIME OVER WEST CENTRAL WI. IT DOES LOOK LIKE LOW
LEVEL THICKNESSES WILL BE COLD ENOUGH TO SUPPORT SOME SNOW OR A
LEAST A RAIN AND SNOW MIX FARTHER SOUTHEAST TOWARD STC/MSP. STILL
AT WIND ADVSY CRITERIA OVER WEST CENTRAL MN AND STRONGER WINDS
WILL LIKELY LAST THROUGH THE MORNING IN THE EASTERN AREAS OF
CURRENT ADVSY. BAND OF 40 KNOT WINDS AT AROUND 925 MB OVER
FAVORED WINDY AREAS SHOWING UP ON THE RUC AND SOME OF THE WIND
GUST PRODUCTS MATCHING AS WELL. IT MIGHT BE CLOSE FOR SOME OF THE
STRONG WINDS FARTHER EAST TOWARD MSP BUT NOT LASTING REAL LONG.
CLEARING BUILDING IN TONIGHT AND THE CURRENT MENTION OF FROST LOOKS
OK UNDER TH RIDGE. STILL RATHER ACTIVE FOR THE REST OF THE WEEK WIT
A COUPLE OF DECENT WAVE IN THE STRONG WESTERLY FLOW. THE SYSTEM
FORECAST TO MOVE INTO THE AREA ON TUESDAY NIGHT AND WEDNESDAY DOES
HAVE SOME INSTABILITY ALONG WITH A WELL DEFINED DIFLUENT FLOW
PATTERN AND PV. HAVE RAISED POPS A BIT MORE INTO THE LIKELY
CATEGORY AND AT LEAST ISOLATED THUNDER LOOKS GOOD PRIMARILY OVER
SOUTH CENTRAL MINNESOTA. THE NEXT SYSTEM IS SIMILAR BUT
INSTABILITY MUCH FARTHER SOUTH...AND MORE OF AN ISENTROPIC LIFT
BAND OF FORCING AFFECTING MAINLY SOUTHERN MN. LOOKS LIKE A QUIET
PERIOD FOR LATER IN THE WEEK AND THE WEEKEND WITH BOTH GFS AND
ECMWF SHOWING AN UPPER RIDGE DEVELOPING IN THE CENTRAL CONUS OR
JUST SLIGHTLY WEST.
&&
.AVIATION.../06Z TAF ISSUANCE/
MOST OF THE CONVECTION/THUNDERSTORMS HAD LIFTED WELL OFF TO THE EAST
OVER NORTHEAST WISCONSIN. STRONG AREA OF LOW PRESSURE HAD MOVED INTO
SOUTHERN MINNESOTA. STRONG NORTHERLY WINDS WERE OCCURRING OVER
WESTERN AND CENTRAL MN...AND SHOULD DEVELOP OVER INTO PORTIONS OF
SOUTH CENTRAL MINNESOTA DURING THE OVERNIGHT HOURS. UPPER LOW HAD
LIFTED NORTH OVER CENTRAL MN...WITH DEFORMATION AXIS EXTENDING FROM
THE UPPER GREAT LAKES BACK OVER INTO EASTERN SOUTH DAKOTA. THE LOW
WILL CONTINUE TO SQUEEZE OUT SOME PRECIPITATION ACROSS THE UPPER
MIDWEST TONIGHT AND MONDAY. THE PRECIPITATION HAD SWITCH OVER TO
LIGHT SNOW NEAR KAXN. AS LOWER LEVELS CONTINUE TO COOL BELOW
FREEZING...THE RAIN WILL BECOME MIXED OR CHANGE OVER TO SNOW OVER
CENTRAL AND THE REST OF SOUTHWEST MN OVERNIGHT. THE LATEST WEATHER
DEPICTION MAP...SHOWED AN AREA OF LOW CLOUDS ALONG THE NORTHERN
PERIMETER OF THE SFC LOW OVER PARTS OF SOUTHERN MN AND NORTHERN
WISCONSIN. CEILING WILL CONTINUE TO LOWER IN THE NEW RICHMOND AND
EAU CLAIRE AREAS AFTER MIDNIGHT. ELSEWHERE...EXPECT WIDESPREAD
MVFR/IFR CONDITIONS THROUGH THE BULK OF THE PERIOD. CONDITIONS WILL
BEGIN TO IMPROVE LATE IN THE DAY ON MONDAY AS DRIER AIR FILTER OVER
THE AREA.
KMSP...SOME PATCHY IFR CONDITIONS THROUGH EARLY MONDAY
MORNING...THEN MARGINAL VFR CONDITIONS PREVAILING THE BULK OF THE
DAY MONDAY. BECOMING VFR BY MONDAY EVENING.
OUTLOOK MON NIGHT/TUESDAY...VFR.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...WIND ADVISORY UNTIL 1 PM CDT THIS AFTERNOON FOR BLUE EARTH-BROWN-
DOUGLAS-FARIBAULT-FREEBORN-KANDIYOHI-LE SUEUR-MARTIN-MCLEOD-
MEEKER-NICOLLET-POPE-RENVILLE-SIBLEY-STEARNS-STEELE-WASECA-
WATONWAN.
WIND ADVISORY UNTIL 7 AM CDT THIS MORNING FOR CHIPPEWA-LAC QUI
PARLE-REDWOOD-STEVENS-SWIFT-YELLOW MEDICINE.
WI...NONE.
&&
$$
JPR/JVM
AREA FORECAST DISCUSSION
NWS BILLINGS MT
253 AM MDT MON APR 16 2012
.SHORT TERM...VALID FOR TDY AND TUE...
RADAR ECHOES HAVE WEAKENED THROUGH THE NIGHT OVER THE BEARTOOTH
AND RED LODGE FOOTHILLS SO WILL CANCEL THE SNOW ADVISORY.
WILL ADD PATCHY FOG THROUGH 15Z TO AREAS THAT RECEIVED
PRECIPITATION YESTERDAY...AS TEMPERATURE/DEW POINT SPREADS WERE
CLOSE EARLY THIS MORNING. HAVE DRIED OUT SE MT THIS MORNING.
BOWMAN RADAR SHOWED NO PRECIPITATION OVER THIS AREA...AND THE
SHORTWAVE IN THE SE WAS MOVING QUICKLY OUT OF THE AREA PER WATER
VAPOR IMAGERY AND RUC DATA. ALSO CONFINED PRECIPITATION CHANCES TO
THE HIGH WESTERN ELEVATIONS OF THE NE BIG HORNS WITH NO RADAR
ECHOES OVER THE AREA AND GFS TIME-HEIGHTS SHOWING FAIRLY HIGH
LEVEL MOISTURE. ALSO CONFINED POPS OVER THE BEARTOOTHS AND
ABSAROKAS TO W-FACING SLOPES FOR SIMILAR REASONS. MODEL CONSENSUS
SUPPORTED ONLY LOW POPS FOR THE WESTERN MOUNTAINS THIS AFTERNOON.
MADE ONLY SLIGHT TEMPERATURE ADJUSTMENTS. EXPECT THE LOW CLOUDS TO
BURN OFF THIS MORNING WITH DAYTIME HEATING.
A PACIFIC SHORTWAVE...SEEN BETWEEN 130 AND 140W ON WATER VAPOR
IMAGERY OFF THE PACIFIC NW COAST...WILL APPROACH THE AREA TONIGHT
BRINGING AN INCREASE IN MOISTURE TO THE WESTERN MOUNTAINS. THE WAVE
WILL PUSH A WARM FRONT THROUGH THE AREA WITH LIMITED MOISTURE. NOTED
THE GFS HAD A SOUTHERN PIECE OF ENERGY MOVING INTO N WY AS
WELL...BUT LOW TO MID LEVEL MOISTURE WAS LIMITED WITH THIS FEATURE
SO WILL NOT ADD ANY POPS TO SHERIDAN COUNTY. THE GOING WESTERN
MOUNTAINS POPS AND SLIGHT CHANCE IN KLVM WERE IN GOOD SHAPE.
AS THE WAVE MOVES ACROSS THE AREA ON TUE IT WILL BE ACCOMPANIED BY
FAIRLY STRONG Q-VECTOR CONVERGENCE. IN ADDITION...BOTH THE WRF AND
GFS SHOWED STEEP 850-700 MB LAPSE RATES. SO THE GOING CHANCE OF
SHOWERS SEEMED FINE AS THE ABOVE FACTORS SHOULD OVERCOME THE
DOWNSLOPE FLOW. LOWERED HIGHS ON TUE BASED ON MIXING PROFILES AND
PARTLY CLOUDY SKIES.
THE SHORTWAVE WILL EXIT THE AREA TUE NIGHT. KEPT SOME POPS OVER
AND NEAR THE SOUTHERN MOUNTAINS TUE EVENING BASED ON THE LOCATION
OF THE MOISTURE. ANOTHER WAVE WILL APPROACH THE AREA LATE TUE
NIGHT IN THE PROGRESSIVE FLOW ALOFT BRINGING A GOOD CHANCE OF
PRECIPITATION TO THE BEARTOOTHS AND ABSAROKAS...WITH LESSER
CHANCES OVER THE ADJACENT FOOTHILLS AND NE BIG HORNS. RAISED MIN
TEMPERATURES A LITTLE BASED ON CLOUD COVER AND EXPECTED 850 MB
TEMPERATURES. ARTHUR
.LONG TERM...VALID FOR WED...THU...FRI...SAT...SUN...
A STREAM OF ENERGY WILL KEEP SHORTWAVE TROUGHINESS OVER THE AREA
WEDNESDAY AND WEDNESDAY NIGHT BEFORE A SURGE OF HEIGHTS OVER THE
PACIFIC NORTHWEST BEGINS A WARMING TREND ON THURSDAY. WHILE THE
TROFFING ON WEDNESDAY IS NOT TOO DEEP IT DOES APPEAR TO BE
SUFFICIENT TO GENERATE SURFACE PRESSURE FALLS OVER WYOMING AND
SOUTH DAKOTA. THIS BRINGS UPSLOPISH FLOW AND WITH AIRMASS UNSTABLE
SHOULD SUPPORT SHOWER ACTIVITY...WITH BEST CHANCES FOR MOISTURE
OVER THE SOUTHERN ZONES. CLOUD COVER AND SHOWER ACTIVITY SHOULD
MAKE WEDNESDAY THE COOLEST DAY OF THE EXTENDED PERIOD.
AS HEIGHTS BUILD OVER WESTERN MONTANA ON THURSDAY IT SHIFTS THE
TROUGH AXIS TO THE MONTANA DAKOTA BORDER AND THUS THE
PRECIPITATION CHANCES WANE FOR THE WESTERN ZONES...ESPECIALLY
THURSDAY NIGHT. THEY PERSIST FOR THE EASTERN ZONES AS PERSISTENT
CONVERGENCE SUPPORTS A BETTER CHANCE FOR MOISTURE. THURSDAY NIGHT
IS A PERIOD OF LOW CONFIDENCE AS THE MODEL RUNS ARE ALTERNATING
BETWEEN SHOWING A STRONGER WAVE MOVING DOWN IN DEVELOPING
NORTHWEST FLOW VERSUS PUSHING THE TROUGH A BIT FURTHER EAST.
EXCEPT FOR THE EAST...EXPECT DECREASING CLOUD COVER TO SUPPORT
WARMER TEMPERATURES.
FRIDAY AND BEYOND RIDGE BUILDS INTO THE REGION WITH A STRONG
WARMING TREND. RIDGE LOOKS SUFFICIENTLY STRONG TO SUPPRESS
CONVECTION OVER THE LOWER ELEVATIONS THOUGH THETA E VALUES DO
INCREASE AS THE RIDGE BUILDS. TEMPERATURES WILL CLIMB INTO THE 70S
FOR THE WEEKEND. BORSUM
&&
.AVIATION...
AREAS OF FOG AND STRATUS WILL PERSIST UNTIL AFTER SUNRISE WEST AND
SOUTH OF AND INCLUDING KBIL. EXPECT QUICKLY IMPROVING CONDITIONS
THROUGH THE MID MORNING HOURS. MOST LOCATIONS WILL REMAIN DRY
THROUGH THE REST OF THE DAY THOUGH SOME MOUNTAIN SHOWERS WILL FORM
INVOF KLVM. BORSUM
&&
.PRELIMINARY POINT TEMP/POPS...
TDY TUE WED THU FRI SAT SUN
-------------------------------------------------------
BIL 059 040/059 036/056 040/061 036/067 042/070 045/074
1/E 14/W 13/W 33/W 22/W 21/B 11/B
LVM 054 036/054 034/052 035/056 032/063 038/067 042/072
1/N 24/W 24/W 43/T 33/W 32/W 21/B
HDN 059 037/062 033/058 035/064 036/069 040/073 041/077
1/E 14/W 13/W 33/W 32/W 21/B 11/B
MLS 055 038/063 032/059 035/060 038/066 042/074 043/077
1/B 14/W 12/W 34/W 32/W 21/B 11/U
4BQ 054 035/062 031/058 034/059 037/066 040/074 040/077
1/B 13/W 04/W 34/W 32/W 21/B 10/U
BHK 052 033/061 031/056 034/057 035/062 038/071 038/073
1/E 14/W 22/W 44/W 32/W 21/N 11/B
SHR 055 034/058 032/056 034/059 036/066 041/074 042/077
1/B 13/W 33/W 33/W 32/W 21/B 10/U
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
349 AM EDT MON APR 16 2012
.SYNOPSIS...
A COLD FRONT CROSSES LATE TODAY. A WAVE DEVELOPS ALONG THE FRONT AND
MAY SKIRT THE REGION TUESDAY NIGHT THROUGH WEDNESDAY EVENING. WARMER
AFTERNOON TEMPERATURES RETURN FOR THE END OF THE WORK WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
TIMING OF FRONT AND PREFRONTAL ACTION LOOKS GOOD FROM PREV FCST.
CONCERNED ABOUT POTENTIAL LACK OF REDEVELOPMENT OF PREFRONTAL BAND
THIS AFTN. MDLS ARE NOT THRILLED WITH BAND LIGHTING BACK UP AS IT
ENTERS WESTERN ZONES BY 18Z. RAPID RUC ALSO LACKLUSTER WITH ITS
MODELED REFLECTIVITY FOR TOMORROW. GIVEN THIS AND STOUT RIDGE
CURRENTLY OVER THE AREA AMID A DRY BL AND THE FACT THIS WILL BE
RACING OUT WELL AHEAD OF ACTUALLY BAROCLINIC ZONE...ELECTED TO
KNOCK DOWN POPS SOME BUT NOT DOWN TO WHAT MDLS SUGGEST. THINKING
OF MORE ISO OR SCT CONCERNING COVERAGE WITH GREATEST COVERAGE
ALONG AND WEST OF OH RVR WITH SUBSEQUENT WEAKENING TOWARD MTNS.
MDL QPF LOOKS MEAGER TO SAY THE LEAST GIVEN LACK OF COVERAGE AND
PROGRESSIVE NATURE. WHAT CONVECTION THAT DOES FORM WILL HAVE TO BE
WATCHED FOR DAMAGING WIND GUSTS AS SPC CONT TO PAINT MUCH
OF CWA IN SLIGHT RISK. AS A RESULT WILL CONT WIND WORDING IN WX GRIDS.
ACTUAL FRONT WILL LAG SEVERAL HRS BEHIND...NOT GETTING INTO SE
OH UNTIL AFTER 00Z...WITH SUBSEQUENT OH RVR CROSSING BY 03Z AND
EXITING MTNS BY 09Z. ELECTED TO HAVE SOME SCHC POPS WITH ACTUAL
FROPA AS ENOUGH FORCING AND MOISTURE MAY EXIST FOR A FEW SHRA.
SHOULD BE WINDY TDY WITH AFTN MIXING AND GRADIENT TIGHTENING.
COULD SEE SOME 25 TO 30KTS GUSTS WITH LCL HIGHER IN ANY CONVECTION
AND WITH FROPA.
CLDS WILL STICK ARND TONIGHT WITH MID/HI LVL MOISTURE ADVECTING IN
FROM SW FLOW ALOFT.
FOR TMPS...LEANED TOWARD WARMER MAV EAST OF OH RVR AND COOLER MET
WEST OF THERE AS CONVECTION WOULD BE FIRING BEFORE MAX HEATING
COULD OCCUR THERE. WILL ALSO GO A HAIR ABV GUIDANCE E AND S FOR
TONIGHT AS BL SLOW TO COOL AND LINGERING CLDS.
WILL BE DECIDING ON ANY FIRE SPS SHORTLY FOR TDY. DWPTS MAY KEEP
RH VALUES OUT OF 20S...HOWEVER ENOUGH MIXING MAY OCCUR TO SEND
DWPTS LWR THAN GUIDANCE SUGGESTS.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
GFS/CANADIAN AND ECMWF ARE SHOWING A WAVE DEVELOPING AND SKIRTING
SOUTHERN AND EASTERN PORTIONS OF THE FORECAST AREA FOR TUESDAY NIGHT
THROUGH WEDNESDAY EVENING. NAM KEEPS THE WAVE SOUTH OF THE
REGION...BUT IS AN OUTLIER. THEREFORE WILL GO WITH A MAJORITY
SOLUTION AND PUSH POPS DEEPER INTO OUR TERRITORY AND INCREASE THEM
IN THE SOUTHEAST. THIS WILL ALSO NECESSITATE LOWERING HIGH
TEMPERATURES ON WEDNESDAY IN THE SOUTHERN AND EASTERN COUNTIES.
CANADIAN/GFS AND ECMWF ARE VERY SIMILAR WITH THE NEXT SYSTEM AS
WELL. THE MODELS WOULD KEEP AN APPROACHING FRONT NORTH OF THE
REGION. WILL KEEP JUST A SMALL POP IN THE NORTH THURSDAY
AFTERNOON...BUT THEN DRY GO THURSDAY NIGHT AS THE FRONT RETREATS
FURTHER NORTH. WITH AREA IN THE WARM SECTOR...WARMED HIGH
TEMPERATURES ON THURSDAY AND FRIDAY.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
QUITE A BIT OF UNCERTAINTY IN THE LONG TERM PERIOD AS MODELS HAVE
RUN TO RUN CONSISTENCY AND OVERALL AGREEMENT ISSUES. BUT GENERAL
CONSENSUS IS THAT A COLD FRONT IN ASSOCIATION WITH A LOW PRESSURE
SYSTEM MOVING EAST THROUGH CANADA WILL STALL OUT SOMEWHERE OVER THE
NORTHERN ZONES LATE THURSDAY/EARLY FRIDAY...WITH A LOW PRESSURE
SYSTEM OUT IN THE PLAINS MOVING NORTHEAST ALONG THE STALLED FRONTAL
BOUNDARY TOWARDS THE REGION FOR THE WEEKEND. THE LOW PRESSURE SYSTEM
AND ASSOCIATED COLD FRONT WILL PUSH EAST THROUGH THE REGION FRIDAY
THROUGH SATURDAY NIGHT...SPREADING SHOWERS AND THUNDERSTORMS INTO
THE REGION. THE LOW WILL MOVE OFF TO THE NORTHEAST ON SUNDAY...WITH
MUCH COOLER AIR FILTERING INTO THE REGION ON THE BACK SIDE OF THE
LOW. ANY LINGERING PRECIPITATION/MOISTURE IN THE NW UPSLOPE FLOW ON
THE BACK SIDE OF THE LOW COULD BE IN THE FORM OF A RAIN/SNOW MIX OR
EVEN SNOW OVER THE NORTHERN MOUNTAIN ZONES AS THE COLDER AIR TAKES
OVER ON THE BACK SIDE OF THE LOW.
&&
.AVIATION /08Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD. HOWEVER...BREEZY
TO GUSTY SW WINDS GENERALLY AROUND THE 20G30KT RANGE WILL CONTINUE
AS WELL THROUGH THE PERIOD AS A COLD FRONT APPROACHES FROM THE
WEST LATE TDY. LLJ 40 TO 50KTS ACROSS THE AREA WARRANT CARRYING
LLWS UNTIL 12Z WHEN MORE GUSTINESS SHOULD KICK IN WITH BETTER
MIXING AFTER SUNRISE.
A BKN LINE OF SHOWERS AND THUNDERSTORMS IS EXPECTED TO MOVE
ACROSS THE AREA ROUGHLY BETWEEN 18Z- 00Z...WEAKENING AS THEY CLOSE
IN ON MTNS. SOME OF THESE STORMS MAY BE STRONG TO SEVERE...WITH
STRONG WINDS. MVFR/LCL IFR IN CONVECTION BUT HAVE KEPT OUT OF TAFS
ATTM DUE TO UNCERTAINTY IN COVERAGE AND OUTSIDE OF TEMPO TIME
FRAME.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z TUESDAY...
FORECAST CONFIDENCE...HIGH.
ALTERNATE SCENARIOS: WIND DIRECTION AND SPEED WILL TEND TO
FLUCTUATE. TIMING OF SHOWERS/THUNDERSTORMS MAY VARY.
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.
DATE MON 04/16/12
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EDT 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13
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 M H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H M H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 06Z TUESDAY...
IFR CONDITIONS POSSIBLE TUESDAY NIGHT THROUGH WEDNESDAY EVENING IN
SOUTHWEST VIRGINIA AND THE SOUTHERN WV MOUNTAINS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...RPY/30
NEAR TERM...30
SHORT TERM...RPY
LONG TERM...SL
AVIATION...
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
333 AM EDT MON APR 16 2012
.SYNOPSIS...
A COLD FRONT OVER INDIANA WILL MOVE EAST THROUGH THE AREA LATER
TODAY AND EARLY TONIGHT THEN HIGH PRESSURE WILL CROSS THE REGION
LATE TUESDAY INTO EARLY WEDNESDAY. ANOTHER COLD FRONT WILL DROP INTO
THE OHIO VALLEY EARLY THURSDAY AND STALL. LOW PRESSURE WILL MOVE
ALONG THE FRONT UP THE OHIO VALLEY FRIDAY AND TO THE MID ATLANTIC
COAST SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM MONDAY EVENING/...
INITIAL BAND OF WEAKENING SHRA/ISOLD TSRA SHOULD MOVE INTO THE NW
CO`S TOWARD DAYBREAK THEN PROGRESS EAST INTO MAINLY THE EASTERN CO`S
FOR THE AFTERNOON. WITH DAYTIME HEATING COULD SEE SOME OF THE STORMS
BECOME SEVERE IN THE EAST WITH DAMAGING WINDS AND TO A LESSER EXTENT
POSSIBLE LARGE HAIL OR A BRIEF TORNADO. COVERAGE OF CONVECTION IN
QUESTION SO WILL STAY WITH JUST CHANCE POPS WHICH IS STILL HIGHER
THAN MAV GUIDANCE.
THE WINDS WILL ALSO BE AN ISSUE OUTSIDE OF THE TSRA AS 850 MB WINDS
AT FRONTAL PASSAGE TIME LOOK TO BE 50 TO 55 KNOTS. AFTER
COLLABORATION HAVE DECIDED TO GO WITH WIND ADVISORY VERSUS WIND
WARNING.
&&
.SHORT TERM /6 PM MONDAY EVENING THROUGH THURSDAY NIGHT/...
HIGH PRESSURE BUILDS IN FROM THE WEST TONIGHT SO STRONG WINDS WILL
DIMINISH FROM WEST TO EAST DURING THE EVENING BUT COULD STILL REMAIN
A LITTLE WINDY FOR THE SNOWBELT LAKESHORE INTO THE LATE NIGHT HOURS.
DRY PUNCH OF AIR BEHIND THE COLD FRONT SHIFTS INTO THE EAST DURING
THE EVENING. WRAP MOISTURE TRIES TO SPREAD EAST INTO THE CWA EARLY
TONIGHT BUT SUBSIDENCE WITH HIGH MOVING IN LOOKS TO BE TOO STRONG TO
ALLOW FOR ENOUGH CLOUDINESS TO PRODUCE ANY PRECIP.
HIGH PRESSURE WITH DRY CONDITIONS SHOULD OCCUR INTO WED NIGHT THEN
ANOTHER COLD FRONT WILL MOVE IN BRINGING A THREAT FOR SHRA MAINLY
FOR THE SECOND HALF OF WED NIGHT.
THE QUESTION FOR THU IS WHETHER THE FRONT WILL HAVE ENOUGH MOMENTUM
TO PUSH FAR ENOUGH S TO TAKE THE SHRA THREAT SOUTH OF THE CWA FOR
THU AFTERNOON AND EVENING. LOW PRESSURE WILL MOVE ALONG THE FRONT
AND SPREAD SHRA BACK NORTH OF THE FRONT THU NIGHT. RIGHT NOW MODELS
WANT TO KEEP GOOD DEEP MOISTURE OVER THE CWA LATE THU AND THU NIGHT
SO WILL SIDE WITH CAUTION AND KEEP THREAT FOR SHRA GOING ALL DAY THU
AS WELL AS THU NIGHT.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
ANOTHER COLD FRONT MOVES THROUGH ON FRIDAY WITH A FAIR AMOUNT OF
COLD AIR BEHIND IT. THE LAKE AND 850 MB TEMPERATURE DIFFERENCE WILL
BE NEAR 11 OR 12C. HIGH PRESSURE SLOWLY BUILDS IN FROM THE WEST. THE
GFS AND ECMWF ARE IN FAIR AGREEMENT FRIDAY AND SATURDAY. FOR SUNDAY
THE 00Z ECMWF HANGS UNTO THE PRECIPITATION LONGER IN THE FORECAST
AREA. AT THIS TIME REMAINED CONSISTENT WITH THE PREVIOUS FORECAST
BUT THIS WILL HAVE TO BE WATCHED. TEMPERATURES WILL BE BELOW NORMAL.
THE THREAT OF FROST IS POSSIBLE SATURDAY NIGHT BUT ESPECIALLY SUNDAY
NIGHT IF THE CLOUDS DECREASE AS EXPECTED.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
GUSTY WINDS AND A THREAT OF THUNDER ARE THE WEATHER PROBLEMS FOR
TODAY. THE SHOWERS AND THUNDERSTORMS OVER INDIANA AND ILLINOIS ARE
DECREASING...HRRR MODEL CONCURS WITH THIS. A NARROW SQUALL LINE
DEVELOPS AHEAD OF THE FRONT LATE THIS MORNING AND MOVES EAST. THE
BEST CHANCE FOR THUNDER IS FROM CLE AND MFD EAST AS THE AIRMASS
WILL GET UNSTABLE ENOUGH.
THE PRESSURE GRADIENT WILL INCREASE DURING THE EARLY MORNING HOURS
AS THE WINDS ALOFT AT 925 MB AND 850 MB INCREASE IN EXCESS OF 50
KNOTS. AS THE WINDS AS THE SURFACE BECOME GUSTY THIS SHOULD
DECREASE THE THREAT OF LLWS. THE HRRR MODEL INCREASES THE GUSTS AT
THE SURFACE IN EXCESS OF 40 KNOTS BY NOON IN THE WARM ADVECTION.
IF WE CAN GET SOME SUNSHINE AND WE SHOULD THAT MAY BE OK. THE
WINDS WILL DECREASE AROUND SUNSET.
VFR FOR CLOUDS AND VISIBILITY EXCEPT IN SHOWERS AND THUNDERSTORMS.
HOWEVER...THE SREF IS TRYING TO INDICATE MVFR CEILINGS DEVELOPING
THIS MORNING AND ENDING THIS AFTERNOON. NOT REAL SURE OF
THIS...WILL NOT FORECAST IT ATTM.
.OUTLOOK...NON-VFR CONDITIONS POSSIBLE LATE MONDAY NIGHT INTO
TUESDAY AND THEN AGAIN WEDNESDAY NIGHT INTO FRIDAY.
&&
.MARINE...
STRONG WARM ADVECTION WILL OCCUR THIS MORNING UNTIL THE COLD FRONT
BEGINS MOVING ACROSS LAKE ERIE FROM WEST TO EAST THIS AFTERNOON.
EVEN THOUGH PLENTY OF WARM AIR AND STRONG WINDS ALOFT...SUSTAINED
WINDS OF 20 TO 25 KNOTS WILL BE LIKELY LATER THIS MORNING AND THEN
BEHIND THE FRONT SUSTAINED WINDS OF 30 KNOTS WITH HIGHER GUSTS. SOME
CONCERN THAT ESPECIALLY ON THE EAST END THE WINDS COULD APPROACH
GALE FORCE. THE COLD ADVECTION IS NOT THAT SIGNIFICANT SO WILL
CONTINUE WITH THE 30 KNOTS SUSTAINED AND A SMALL CRAFT ADVISORY. THE
WINDS WILL DECREASE FROM WEST TO EAST TUESDAY AS HIGH PRESSURE
BUILDS IN. UNTIL THAT HAPPENS THE WATER LEVEL ON THE WEST END OF
LAKE ERIE COULD DROP LATE THIS AFTERNOON AND EVENING. AT THIS TIME
IT IS NOT EXPECTED TO DROP TO BELOW THE CRITICAL MARK FOR SAFE
NAVIGATION...THIS WILL BE WATCHED CLOSELY BY THE NEXT SHIFTS.
SOME MINOR THREAT THAT WAVES COULD APPROACH SMALL CRAFT ADVISORY ON
THURSDAY AFTER A COLD FRONTAL PASSAGE. AT THIS TIME 2 TO 4 FOOT
WAVES SEEM TO BE THE HIGHEST.
THE NEXT THREAT OF A SMALL CRAFT ADVISORY WILL BE FRIDAY NIGHT INTO
SUNDAY AS A LOW AND FRONT MOVES NEAR LAKE ERIE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...WIND ADVISORY FROM 10 AM THIS MORNING TO 10 PM EDT THIS
EVENING FOR OHZ003-006>014-017>023-027>033-036>038-047-
089.
PA...WIND ADVISORY FROM 10 AM THIS MORNING TO 10 PM EDT THIS
EVENING FOR PAZ001>003.
MARINE...SMALL CRAFT ADVISORY FROM 9 AM THIS MORNING TO 4 PM
EDT TUESDAY FOR LEZ147>149.
SMALL CRAFT ADVISORY FROM 9 AM THIS MORNING TO 10 AM EDT
TUESDAY FOR LEZ142>146.
&&
$$
SYNOPSIS...ADAMS
NEAR TERM...ADAMS
SHORT TERM...ADAMS
LONG TERM...KIELTYKA
AVIATION...KIELTYKA
MARINE...KIELTYKA
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
313 AM EDT MON APR 16 2012
.SYNOPSIS...
A COLD FRONT CROSSES LATE TODAY. WEAK UPPER LEVEL DISTURBANCE PASSES
TUESDAY AND TUESDAY NIGHT. HIGH PRESSURE FOLLOWS THROUGH THE END
OF WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
TIMING OF FRONT AND PREFRONTAL ACTION LOOKS GOOD FROM PREV FCST.
CONCERNED ABOUT POTENTIAL LACK OF REDEVELOPMENT OF PREFRONTAL BAND
THIS AFTN. MDLS ARE NOT THRILLED WITH BAND LIGHTING BACK UP AS IT
ENTERS WESTERN ZONES BY 18Z. RAPID RUC ALSO LACKLUSTER WITH ITS
MODELED REFLECTIVITY FOR TOMORROW. GIVEN THIS AND STOUT RIDGE
CURRENTLY OVER THE AREA AMID A DRY BL AND THE FACT THIS WILL BE
RACING OUT WELL AHEAD OF ACTUALLY BAROCLINIC ZONE...ELECTED TO
KNOCK DOWN POPS SOME BUT NOT DOWN TO WHAT MDLS SUGGEST. THINKING
OF MORE ISO OR SCT CONCERNING COVERAGE WITH GREATEST COVERAGE
ALONG AND WEST OF OH RVR WITH SUBSEQUENT WEAKENING TOWARD MTNS.
MDL QPF LOOKS MEAGER TO SAY THE LEAST GIVEN LACK OF COVERAGE AND
PROGRESSIVE NATURE. WHAT CONVECTION THAT DOES FORM WILL HAVE TO BE
WATCHED FOR DAMAGING WIND GUSTS AS SPC CONT TO PAINT MUCH
OF CWA IN SLIGHT RISK. AS A RESULT WILL CONT WIND WORDING IN WX GRIDS.
ACTUAL FRONT WILL LAG SEVERAL HRS BEHIND...NOT GETTING INTO SE
OH UNTIL AFTER 00Z...WITH SUBSEQUENT OH RVR CROSSING BY 03Z AND
EXITING MTNS BY 09Z. ELECTED TO HAVE SOME SCHC POPS WITH ACTUAL
FROPA AS ENOUGH FORCING AND MOISTURE MAY EXIST FOR A FEW SHRA.
SHOULD BE WINDY TDY WITH AFTN MIXING AND GRADIENT TIGHTENING.
COULD SEE SOME 25 TO 30KTS GUSTS WITH LCL HIGHER IN ANY CONVECTION
AND WITH FROPA.
CLDS WILL STICK ARND TONIGHT WITH MID/HI LVL MOISTURE ADVECTING IN
FROM SW FLOW ALOFT.
FOR TMPS...LEANED TOWARD WARMER MAV EAST OF OH RVR AND COOLER MET
WEST OF THERE AS CONVECTION WOULD BE FIRING BEFORE MAX HEATING
COULD OCCUR THERE. WILL ALSO GO A HAIR ABV GUIDANCE E AND S FOR
TONIGHT AS BL SLOW TO COOL AND LINGERING CLDS.
WILL BE DECIDING ON ANY FIRE SPS SHORTLY FOR TDY. DWPTS MAY KEEP
RH VALUES OUT OF 20S...HOWEVER ENOUGH MIXING MAY OCCUR TO SEND
DWPTS LWR THAN GUIDANCE SUGGESTS.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
CONTINUED WITH CONVECTION ASSOCIATED WITH COLD
FRONT...DIMINISHING IN INTENSITY AS FRONT EXITS THE EASTERN
MOUNTAINS LATE MONDAY NIGHT. GOOD AGREEMENT AND CONSISTENCY AMONG
MODELS LET US HAVE GOOD CONFIDENCE WITH THIS SYSTEM.
THEREFORE...KEPT HIGH LIKELY POPS ALONG AND AHEAD FRONT EXODUS.
LINGERING RAIN SHOWERS BEHIND THE SLOWLY PROGRESSING FRONT WARRANT
LOW CHANCES EARLY TUESDAY MAINLY EASTERN MOUNTAINS. A SECOND H5
VORT MAX IS EVIDENT IN TUESDAY NIGHT TO PROVIDE SOME FORCING FOR
ANY LOW LEVEL MOISTURE TRAPPED WEST OF THE MOUNTAINS FOR
CONTINUING LOW CHANCES THROUGH TUESDAY NIGHT. KEPT THUNDER OUT FOR
NOW BEHIND THE FRONT INTO TUESDAY NIGHT.
THE AFOREMENTIONED SCENARIO...TOGETHER WITH SKY COVER GUIDANCE
FROM THE GMOS...CMC HEM AND NAM12 INDICATE AREAS OF CLEARING
ACROSS PORTIONS OF SOUTHEAST OH...CENTRAL AND NORTHERN WV
SPREADING MONDAY NIGHT INTO TUESDAY. THIS WILL ALLOW WARMER LOW
TEMPERATURES ACROSS THE CENTRAL AND SOUTHERN MOUNTAINS...INCLUDING
SOME OF THE SOUTHERN COAL FIELDS THROUGH THE KY COUNTIES MONDAY
NIGHT...AND WARMER HIGH TEMPS TUES PER MORE PERIODS OF SUNSHINE
FARTHER NORTH AND WEST. THEREFORE...STARTED WITH THE BLEND OF MAV
AND MET NUMBERS TWEAKING UP OR DOWN DEPENDING ON CLOUD COVER.
SAME REASONING FOR HIGH TEMPS ON WEDNESDAY PER CLOUDS ASSOCIATED
WITH THE SECOND H5 WAVE AFFECTING THE SOUTHEAST QUADRANT OF OUR
CWA.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
QUITE A BIT OF UNCERTAINTY IN THE LONG TERM PERIOD AS MODELS HAVE
RUN TO RUN CONSISTENCY AND OVERALL AGREEMENT ISSUES. BUT GENERAL
CONSENSUS IS THAT A COLD FRONT IN ASSOCIATION WITH A LOW PRESSURE
SYSTEM MOVING EAST THROUGH CANADA WILL STALL OUT SOMEWHERE OVER THE
NORTHERN ZONES LATE THURSDAY/EARLY FRIDAY...WITH A LOW PRESSURE
SYSTEM OUT IN THE PLAINS MOVING NORTHEAST ALONG THE STALLED FRONTAL
BOUNDARY TOWARDS THE REGION FOR THE WEEKEND. THE LOW PRESSURE SYSTEM
AND ASSOCIATED COLD FRONT WILL PUSH EAST THROUGH THE REGION FRIDAY
THROUGH SATURDAY NIGHT...SPREADING SHOWERS AND THUNDERSTORMS INTO
THE REGION. THE LOW WILL MOVE OFF TO THE NORTHEAST ON SUNDAY...WITH
MUCH COOLER AIR FILTERING INTO THE REGION ON THE BACK SIDE OF THE
LOW. ANY LINGERING PRECIPITATION/MOISTURE IN THE NW UPSLOPE FLOW ON
THE BACK SIDE OF THE LOW COULD BE IN THE FORM OF A RAIN/SNOW MIX OR
EVEN SNOW OVER THE NORTHERN MOUNTAIN ZONES AS THE COLDER AIR TAKES
OVER ON THE BACK SIDE OF THE LOW.
&&
.AVIATION /07Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD. HOWEVER...BREEZY
TO GUSTY SW WINDS GENERALLY AROUND THE 20G30KT RANGE WILL CONTINUE
AS WELL THROUGH THE PERIOD AS A COLD FRONT APPROACHES FROM THE
WEST LATE TDY. LLJ 40 TO 50KTS ACROSS THE AREA WARRANT CARRYING
LLWS UNTIL 12Z WHEN MORE GUSTINESS SHOULD KICK IN WITH BETTER
MIXING AFTER SUNRISE.
A BKN LINE OF SHOWERS AND THUNDERSTORMS IS EXPECTED TO MOVE
ACROSS THE AREA ROUGHLY BETWEEN 18Z- 00Z...WEAKENING AS THEY CLOSE
IN ON MTNS. SOME OF THESE STORMS MAY BE STRONG TO SEVERE...WITH
STRONG WINDS. MVFR/LCL IFR IN CONVECTION BUT HAVE KEPT OUT OF TAFS
ATTM DUE TO UNCERTAINITY IN COVERAGE AND OUTSIDE OF TEMPO TIME
FRAME.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z TUESDAY...
FORECAST CONFIDENCE...HIGH.
ALTERNATE SCENARIOS: WIND DIRECTION AND SPEED WILL TEND TO
FLUCTUATE. TIMING OF SHOWERS/THUNDERSTORMS MAY VARY.
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.
DATE MON 04/16/12
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EDT 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13
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 M H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY H H H H H H H H H H H H
PKB CONSISTENCY H H H H H H H H H M H H
CKB CONSISTENCY H H H H H H H H H H H H
AFTER 06Z TUESDAY...
NO IFR EXPECTED.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...TRM/RPY/30
NEAR TERM...30
SHORT TERM...ARJ
LONG TERM...SL
AVIATION...30
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
206 AM EDT MON APR 16 2012
.SYNOPSIS...
A COLD FRONT WILL MOVE ACROSS THE REGION ON MONDAY AS LOW PRESSURE
RACES FROM THE WESTERN GREAT LAKES INTO QUEBEC. HIGH PRESSURE WILL
THEN MOVE INTO THE AREA FOR TUESDAY INTO WEDNESDAY. THE NEXT AREA
OF LOW PRESSURE MAY MOVE ACROSS ONTARIO WEDNESDAY NIGHT WITH A
COLD FRONT PASSING THROUGH THE REGION ON THURSDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
UPDATE...MADE ADJUSTMENT TO CLOUDS...POPS AND WX FOR MONDAY AS
WELL AS VARIOUS ADJUSTMENTS FOR THE OVERNIGHT. STILL EXPECT MAINLY
VARIABLE CLOUDS OVERNIGHT ALTHOUGH THERE SHOULD BE A TREND TOWARD
CLOUDS INCREASING AS SYSTEM APPROACHES FROM THE WEST. TOWARD
MORNING BROUGHT CHANCE POPS INTO THE FAR NORTHWEST. LINE LOOKS GOOD
AT PRESENT ALTHOUGH HRRR INDICATES THIS SHOULD WEAKEN AS IT
APPROACHES SO WANTED TO BEGIN WITH A CHANCE POP. EXPECT THROUGH
THE MORNING AND EARLY AFTERNOON COVERAGE WILL INCREASE SO WENT
WITH LIKELY FROM CENTRAL COUNTIES EAST FROM ABOUT NOON ON. WINDS
CONTINUE TO LOOK GOOD FOR TOMORROW SO ANTICIPATE THE NEED FOR A
HEADLINE. WILL ALLOW NEXT SHIFT TO PICK TIMING AND LOCATION BASED
ON NEW GUIDANCE.
PREVIOUS...GUSTY SOUTHERLY WINDS ARE EXPECTED THROUGH THE NIGHT
AS LOW PRESSURE OVER THE PLAINS SLOWLY MOVES TOWARD THE REGION.
OTHERWISE VARIABLE AMOUNTS OF HIGH LEVEL CLOUD COVER AND THE
STRONG WARM ADVECTION WILL LEAD TO A WARM NIGHT. MOST LOCATIONS
WILL BE NEAR TO SLIGHTLY ABOVE 60.
BESIDES THE FEW THUNDERSTORMS THAT ARE ATTEMPTING TO CLIP THE
ERIE AREA THROUGH 6 PM IT APPEARS THE THREAT OF RAIN IS VERY LOW.
HOWEVER AS THE COLD FRONT MOVES CLOSER TO THE REGION TOWARD
SUNRISE THERE MAY BE A FEW SCATTERED THUNDERSTORMS THAT DRIFT INTO
THE WESTERN COUNTY WARNING AREA.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY NIGHT/...
THE COLD FRONT WILL MOVE INTO NW OHIO EARLY MONDAY MORNING. THERE
IS MUCH UNCERTAINTY WITH THE AMOUNT OF CONVECTION THAT WILL BE
LOCATED NEAR THE FRONTAL BOUNDARY IN THE MORNING. MOISTURE LEVELS
MAY BE DIFFICULT TO KEEP ELEVATED ON MONDAY IF SOME DEEPER MIXING
CAN OCCUR AHEAD OF THE FRONT. THIS COULD HAVE A LIMITING AFFECT ON
THE THUNDERSTORM DEVELOPMENT AS THE FRONT MOVES TOWARD PA. STRONG
LOW LEVEL JET AHEAD OF THE FRONT WILL BE A FACTOR WITH THE
THUNDERSTORMS THAT CAN DEVELOP. SOME OF THIS WIND MAY BE BROUGHT
TO THE SURFACE WITH THE STRONGEST CONVECTION. HOWEVER THE MAIN
CONCERN WILL BE THE GUSTY WINDS AWAY FROM THE THUNDERSTORMS AS WE
ATTEMPT TO MIX THE STRONGER WINDS TO THE SURFACE WHERE HIGHS GET
INTO THE UPPER 70S. WINDS IN THE WAKE OF THE FRONT WILL ALSO
APPROACH ADVISORY LEVELS FOR A FEW HOURS. DID NOT HOIST A WIND
ADVISORY AT THIS TIME BUT THE POTENTIAL WILL CONTINUE TO BE
MENTIONED IN THE HWO.
HIGH PRESSURE WILL MOVE INTO THE REGION BY TUESDAY AND PERSIST
INTO WEDNESDAY. THIS WILL BRING DRIER AIR INTO THE REGION THAT
WILL ALLOW FOR LARGER DIURNAL RANGES. THE COLDEST NIGHT LOOKS LIKE
IT WILL BE TUESDAY NIGHT WITH MANY LOCATIONS ACROSS THE EASTERN
HALF OF THE AREA DIPPING TO AROUND 30 DEGREES. WARMER BY WEDNESDAY
AFTERNOON WITH HIGHS VERY CLOSE TO SEASONAL LEVELS.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
A WEAK COLD FRONT WILL MOVE THROUGH THE AREA THURSDAY AND HAS A
MINIMAL CHANCE OF PRODUCING SOME SHOWER ACTIVITY. MAINLY DUE TO THE
WEAK UPPER LEVEL AND MOISTURE SUPPORT. LOW PRESSURE WILL MOVE INTO
THE REGION FRIDAY EVENING AND BRING YET ANOTHER ROUND OF SHOWERS TO
THE REGION AS AN UPPER LEVEL TROUGH DIGS INTO THE EASTERN UNITED
STATES.
THE UPPER LEVEL TROUGH WILL LINGER INTO THE WEEKEND AND MOVE LITTLE
AS AMPLIFICATION OF THE RIDGE TAKES PLACE IN THE CENTRAL UNITED
STATES. THIS MEANS A TREND TOWARD COOLER TEMPERATURES DURING THE
WEEKEND. TEMPERATURES WILL LIKELY BE COOL ENOUGH TO SUPPORT THE MIX
OF RAIN AND WET SNOW SATURDAY NIGHT.
MODELS ARE SUGGESTING DRYING CONDITIONS RETURNING FOR SUNDAY INTO
SUNDAY NIGHT AS WEAK HIGH PRESSURE BUILDS EAST OVER THE REGION.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
GUSTY WINDS AND A THREAT OF THUNDER ARE THE WEATHER PROBLEMS FOR
TODAY. THE SHOWERS AND THUNDERSTORMS OVER INDIANA AND ILLINOIS ARE
DECREASING...HRRR MODEL CONCURS WITH THIS. A NARROW SQUALL LINE
DEVELOPS AHEAD OF THE FRONT LATE THIS MORNING AND MOVES EAST. THE
BEST CHANCE FOR THUNDER IS FROM CLE AND MFD EAST AS THE AIRMASS
WILL GET UNSTABLE ENOUGH.
THE PRESSURE GRADIENT WILL INCREASE DURING THE EARLY MORNING HOURS
AS THE WINDS ALOFT AT 925 MB AND 850 MB INCREASE IN EXCESS OF 50
KNOTS. AS THE WINDS AS THE SURFACE BECOME GUSTY THIS SHOULD
DECREASE THE THREAT OF LLWS. THE HRRR MODEL INCREASES THE GUSTS AT
THE SURFACE IN EXCESS OF 40 KNOTS BY NOON IN THE WARM ADVECTION.
IF WE CAN GET SOME SUNSHINE AND WE SHOULD THAT MAY BE OK. THE
WINDS WILL DECREASE AROUND SUNSET.
VFR FOR CLOUDS AND VISIBILITY EXCEPT IN SHOWERS AND THUNDERSTORMS.
HOWEVER...THE SREF IS TRYING TO INDICATE MVFR CEILINGS DEVELOPING
THIS MORNING AND ENDING THIS AFTERNOON. NOT REAL SURE OF
THIS...WILL NOT FORECAST IT ATTM.
.OUTLOOK...NON-VFR CONDITIONS POSSIBLE LATE MONDAY NIGHT INTO
TUESDAY AND THEN AGAIN WEDNESDAY NIGHT INTO FRIDAY.
&&
.MARINE...
WARM AIR ADVECTION TAKING PLACE OVER THE LAKE WILL LIKELY CAUSE
STRONGER WINDS AT THE SURFACE TO RIDE UP AND OVER THE COLD DOME.
THIS SHOULD KEEP WINDS BELOW SMALL CRAFT ADVISORY CRITERIA AT THE
LAKE SURFACE UNTIL COLD FRONT MOVES THROUGH LATE MONDAY AFTERNOON
AND EVENING.
WILL LIKELY NEED TO HOIST SMALL CRAFT ADVISORIES TOMORROW NIGHT AND
WILL POSSIBLY BE ABLE TO DROP IT BY TUESDAY AFTERNOON AS WINDS
DIMINISH CONSIDERABLY.
GENERALLY LIGHT FLOW EXPECTED INTO THURSDAY AND MARGINAL SMALL CRAFT
WAVES WILL LIKELY DEVELOP THURSDAY NIGHT BUT DIMINISH ON FRIDAY.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MULLEN
NEAR TERM...TK/MULLEN
SHORT TERM...MULLEN
LONG TERM...LOMBARDY
AVIATION...KIELTYKA
MARINE...LOMBARDY
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
209 AM EDT MON APR 16 2012
.SYNOPSIS...
WELL ABOVE NORMAL TEMPERATURES WILL OCCUR ON MONDAY IN ADVANCE OF A
COLD FRONT WHICH WILL TRAVERSE THE REGION TOMORROW EVENING. HIGH
PRESSURE WILL BUILD IN FOR THE REST OF THE WEEK. A DEEPENING
TROUGH WILL LIKELY FORM OVER THE EASTERN CONUS BY NEXT WEEKEND.
&&
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
CIRRUS CLOUDS AND A SW BREEZE WILL KEEP TEMPS VERY MILD EARLY THIS
MORNING WITH MOST LOCATIONS BOTTOMING OUT IN THE 50S. SATL TRENDS
AND RUC 400-200MB RH FIELDS SUGGEST CIRRUS WILL LIFT NORTH OF THE
AREA BY ARND 12Z.
&&
.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM TUESDAY/...
ANOMALOUSLY WARM AIR MASS AND A CLEAR SKY FOR THE FIRST PART OF
THE DAY WILL LEAD TO SOME SPOTS GETTING TO WITHIN 4-5F OF THEIR
DAILY RECORD MAXES. THE GEFS MEAN 850 TEMPS ARE CLOSE TO 15C.
SUCH 8H TEMPS SHOULD EASILY TRANSLATE TO HIGH TEMPS FROM THE U70S
ALLEGHENY MTNS...TO THE M80S OVER THE SUSQ VALLEY. DEWPOINTS
TOMORROW WILL BE IN THE MID TO UPPER 50S...THOUGH IT SHOULDNT FEEL
ADVERSELY MOIST GIVEN THE STRONG PRESSURE GRADIENT MOVING THROUGH
THE REGION. BUFKIT SOUNDING DATA SUPPORTS GUSTS BTWN 25-35KTS
ACROSS THE NW DURING THE LATE MORNING AND THROUGH THE AFTERNOON AS
WINDS MIX TO THE SFC. DECENT SPEED SHEAR AHEAD OF THE FRONT AS
THE NOSE OF A LL JET WORKS THRU THE GREAT LAKES MAY COUPLE WITH
THE WARM MOIST TO ALLOW FOR MARGINALLY UNSTABLE CONDITIONS TO FORM
PM TSRA IN WRN PA AND MOVE IT TO THE EAST ALONG WITH THE FRONT AS
IT TRAVERSES THE COMMONWEALTH. DOWNSLOPE EFFECTS AND LOSS OF A
GOOD MOISTURE SOURCE SHOULD WEAKEN AND DISSIPATE THE SCT
CONVECTION IN THE EVENING. MODEL DATA AND SPC OUTLOOKS POINT TO A
MARGINAL SVR WX THREAT ACROSS THE N/WRN COUNTIES EARLY IN THE
EVENING BEFORE THE CONVECTION WANES.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
WENT WITH A CHC OF SHOWERS AND THUNDERSTORMS ACROSS THE MOUNTAINS
MONDAY EVENING. AGREE WITH SPC...PHI...ETC...NOT MUCH WILL MAKE
IT EAST OF THE MOUNTAINS...AS DYNAMICS ARE TO THE WEST...LACK
OF SFC CONVERGENCE...AND HEATING IS LOST. HOWEVER..REMAINS OF
CONVECTION TO THE WEST WILL LIKELY MAKE IT INTO THE MOUNTAINS...
GIVEN TIMING.
TUE LOOKS LIKE A NICE DAY. SOMEWHAT BREEZY. IT WILL BE DRY OUT...
AS DEWPOINT DEPRESSIONS WILL BE IN THE 30 TO 40 DEGREE RANGE LATE
IN THE DAY. WENT WARMER THAN GUIDANCE.
FOR TUE NIGHT...EXPECT NOT A LOT OF CLDS OR WIND. WITH DRY AIR
IN PLACE...WENT WITH LOWER TEMPS.
WED LOOKS LIKE ANOTHER DECENT DAY. WITH WITH SLIGHTLY HIGHER
TEMPS.
THERE COULD BE A SHOWER ACROSS THE FAR NW LATE WED NIGHT.
FOR THU...THERE WILL BE A CHC OF A SHOWER...MAINLY NORTH AND
WEST OF THE LOWER SUSQUEHANNA VALLEY.
NOT LOOKING AT MUCH GOING ON THU NIGHT.
THE BIG STORY WILL BE FRIDAY INTO NEXT SUNDAY. WHILE SOME
OF THE MODELS MAY BE OVERDONE WITH THE SYSTEM...THE PATTERN
SUPPORTS A FAIRLY DEEP LOW WITH BREEZY AND COLD TEMPS...AND
PRECIPITATION. THERE WILL LIKELY BE A TIGHT WEST...EAST
TEMP GRADIENT FROM NW TO SE. RAIN COULD BE ON THE HEAVY SIDE.
I HAVE SOME SNOW IN FOR NEXT SUNDAY MORNING...AS SOME COULD
MIX WITH THE RAIN ON THE WEST SIDE OF THE LOW...GIVEN COLD
ADVECTION...AND SIGNIFICANT MOISTURE. STILL SOME CHC SUNDAY
NIGHT...BUT AIRMASS WILL BE MODERATING...AND MOISTURE STARTING
TO LIFT OUT...THUS I LEFT SNOW OUT FOR SUNDAY NIGHT.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS PREVAIL ACROSS THE REGION. HAVE INCLUDED A PERIOD
OF MVFR VSBYS OVER KIPT...KMDT AND KLNS DUE TO LOWERED T/TD
SPREAD OF ONLY 3 TO 5 DEGREES AND LIGHT SURFACE WINDS. OVER
CENTRAL AND WESTERN AIRFIELDS...T/TD SPREADS REMAIN 8-10 DEGREES
SO LOWER CONFIDENCE OF FOG. HOWEVER...WILL WATCH FOR POSSIBLE FOG
FORMATION AS THE NIGHT CONTINUES IN THESE LOCATIONS AS WELL.
VFR CONDITIONS FOR MONDAY. APPROACHING FRONT WILL BRING A CHANCE
OF SHOWERS AND THUNDERSTORMS TO NW REGIONS...ESPECIALLY KBFD. HAVE
NOT INCLUDED IN TAF AT THIS TIME BASED ON UNCERTAINTY IN COVERAGE.
STRENGTHENING SOUTHWESTERLY LOW LEVEL JET WILL HAS INTRODUCED
LLWS INTO MOST CENTRAL PA AIRFIELDS THROUGH ABOUT NOONTIME.
EXCEPTION IS IN FAR SOUTHEAST WHERE LOW LEVEL JET WINDS EXPECTED
TO BE LESS VIGOROUS. LLWS CONDITIONS WILL ABATE AS WINDS MIX DOWN
AND SURFACE WINDS BECOME GUSTY DURING THE LATE MORNING/EARLY
AFTERNOON.
OUTLOOK...
TUE-FRI...VFR. MAY SEE SOME SHRA THU PM/FRI AS NEXT FRONT
APPROACHES.
&&
.CTP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DANGELO/CERU
NEAR TERM...FITZGERALD
SHORT TERM...DANGELO/CERU
LONG TERM...MARTIN
AVIATION...JUNG/DEVOIR
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
222 AM CDT MON APR 16 2012
.UPDATE...
EARLY AM UPDATE REFLECTS OUTFLOW TRIGGERED CONVECTION OVER OUR
SOUTHEAST COUNTIES. DPROG/DT ANALYSIS OF MODELS SHOWS AN
INCREASING TREND TOWARD CONVECTION BACKING WESTWARD INTO OUR
CENTRAL COUNTIES...AND SATELLITE IMAGERY REFLECTS THIS TREND WITH
GROWING MID-LEVEL CLOUDS OVER OUR WESTERN COUNTIES. PER SPENES
ISSUANCE LAST HOUR...THE FAR SOUTHEAST COUNTIES MAY SEE SPOTTY
RAINFALL TOTALS IN EXCESS OF 2 INCHES FROM SLOW MOVING ACTIVITY
AND VERY COLD CLOUD TOPS. ROUTINE MORNING PACKAGE IS ALMOST
COMPLETED WITHIN THIS EARLY MORNING UPDATE...AND CONTINUES TO SHOW
ANOTHER ROUND OF RAINS POSSIBLE FOR FRIDAY. WILL CONTINUE TO
MONITOR THE CONVECTIVE TRENDS AND ADDITIONAL MODEL DATA TO MAKE
MAINLY 1ST AND 2ND PERIOD CHANGES AS NEEDED BEFORE SENDING OUT THE
FULL MORNING FORECAST PACKAGE.
&&
.PREV DISCUSSION... /ISSUED 1156 PM CDT SUN APR 15 2012/
AVIATION...
WEAK DISTURBANCES WILL PUSH ACROSS TONIGHT BEHIND A COLD FRONT WHICH
WILL STALL ALONG THE COASTAL REGIONS. VFR CLOUDINESS WILL CONTINUE OVER
THE I-35 CORRIDOR TAF SITES DUE TO CLOUD DEBRIS BLOWOFF FROM CONVECTION
ALONG THE COASTAL PLAINS. MOSTLY VFR CLEAR KDRT SITE TONIGHT.
ANOTHER DISTURBANCE APPROACHING FROM THE WEST LATE MONDAY AND
MONDAY NIGHT WILL BRING INCREASING MID AND UPPER LEVEL CLOUDINESS
TO THE AREA. I-35 CORRIDOR TERMINALS VARIABLE CLOUDS AOA 6 THSD.
LIGHT NORTH WINDS BECOMING LIGHT NORTHEAST MONDAY. KDRT TERMINAL
VFR CLEAR. KDRT WINDS LIGHT NORTH TONIGHT AND EARLY MONDAY
BECOMING LIGHT EASTERLY BY MIDDAY.
PREV DISCUSSION... /ISSUED 1139 PM CDT SUN APR 15 2012/
UPDATE...
A BIT SURPRISED BY THE RESURGENCE IN CONVECTION ALONG THE FRONT
OVER THE COASTAL PLAINS...SO WE HAD TO PUT POPS FOR SHOWERS AND
THUNDERSTORMS BACK INTO THE FORECAST FOR THE SOUTHEASTERN
COUNTIES. IT STILL SEEMS MOST OF THE ACTIVITY WILL REMAIN OUTSIDE
OF OUR AREA.
PREV DISCUSSION... /ISSUED 1007 PM CDT SUN APR 15 2012/
UPDATE...
JUST SENT A QUICK GRID AND TEXT UPDATE TO REMOVE POPS IN THE FAR
SOUTHEAST COUNTIES AND RETREND TEMPS...DEW POINTS...AND WINDS
OVERNIGHT. NO MAJOR CHANGES TO THE OVERALL FORECAST.
PREV DISCUSSION... /ISSUED 327 PM CDT SUN APR 15 2012/
DISCUSSION...
THE SFC FRONT IS SLOWLY WORKING ITS WAY INTO THE COASTAL
PLAINS...WITH SCATTERED CONVECTION CONTINUING ALONG THE FRONTAL
BOUNDARY. THE FRONT IS EXPECTED TO STALL ALONG THE COAST LATER
TONIGHT...WITH GOOD CONSENSUS AMONG THE NAM/GFS OF POST-FRONTAL
PRECIPITATION CONTINUING ACROSS OUR SOUTHERN COUNTIES.
HOWEVER...THE 18Z RUC AND 12Z HI-RES BOTH INDICATE THE PRECIP AXIS
WILL SHIFT COMPLETELY SOUTH OF OUR CWA THIS EVENING. HAVE SOMEWHAT
SPLIT THE DIFFERENCE AND KEPT TOKEN POPS ACROSS OUR SOUTHEASTERN
TIER OF COUNTIES FOR THIS EVENING.
AS THE FRONT STALLS ALONG THE COAST OVERNIGHT...THE MID-UPPER
LEVEL TROUGH AXIS WILL REMAIN NORTHWEST OF OUR AREA. THEREFORE
SOME POST-FRONTAL SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP
ACROSS THE SOUTHEASTERN HALF OF THE REGION TOMORROW AND INTO
TOMORROW NIGHT. RAIN CHANCES WILL CLEAR THE AREA ON TUESDAY AS THE
UPPER TROUGH AXIS SLIDES TO THE EAST OF THE REGION AND DRIER NW
FLOW ALOFT SETTLES INTO THE AREA. MOSTLY DRY AND SEASONABLE
CONDITIONS WILL PREVAIL THROUGH THE MIDDLE OF THE WEEK WITH
ONSHORE FLOW RETURNING LATE TUESDAY/EARLY WEDS. THE INCREASING LOW
LEVEL MOISTURE WILL RESULT IN A SLOW WARMING TREND THROUGH THE END
OF THE WEEK.
MID/LONG-RANGE MODELS CONTINUE TO HAVE FAIR CONSENSUS ON AN UPPER
TROUGH/COLD FRONT FOR OUR AREA LATE IN THE WEEK. CURRENT THINKING
IS THAT THE BEST TIME-FRAME FOR RAIN WOULD BE FRI AFTERNOON/NIGHT.
HOWEVER...THIS COULD EASILY SHIFT TO A FRI NIGHT/SAT MORNING OR
LATER SCENARIO GIVEN WE`RE TALKING ABOUT 126-PLUS HRS FROM NOW.
FIRE WEATHER...
ELEVATED TO NEAR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED
ACROSS THE SOUTHERN EDWARDS PLATEAU AND RIO GRANDE PLAINS THROUGH
THIS EVENING IN THE WAKE OF THE COLD FRONT. LOW RELATIVE HUMIDITIES
AND GUSTY NORTHWEST WINDS NEAR 15 MPH WILL CONTINUE THROUGH THE
REMAINDER OF THE AFTERNOON WITH WINDS DECREASING TO 10 TO 15 MPH
AFTER SUNSET. RH VALUES WILL BE SLOWER TO RECOVER. ELEVATED FIRE
WEATHER CONDITIONS ARE EXPECTED ACROSS WESTERN AREAS ON MONDAY
AFTERNOON MAINLY DUE TO LOW HUMIDITIES AS WINDS WILL BE AT OR
BELOW 10 MPH.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 79 57 82 60 83 / 20 30 - - -
AUSTIN BERGSTROM INTL AIRPORT 79 55 81 55 82 / 20 30 - - -
NEW BRAUNFELS MUNI AIRPORT 79 57 81 58 81 / 30 30 - - -
BURNET MUNI AIRPORT 79 51 80 56 81 / 10 10 0 - -
DEL RIO INTL AIRPORT 84 58 85 62 86 / 0 - 0 - -
GEORGETOWN MUNI AIRPORT 78 52 80 55 81 / 20 20 - - -
HONDO MUNI AIRPORT 80 53 82 57 82 / 10 10 0 - -
SAN MARCOS MUNI AIRPORT 78 56 80 57 81 / 30 30 - - -
LA GRANGE - FAYETTE REGIONAL 78 60 80 59 81 / 40 30 10 - -
SAN ANTONIO INTL AIRPORT 79 57 82 59 82 / 20 20 - - -
STINSON MUNI AIRPORT 79 58 82 59 83 / 30 20 - - -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...01
SYNOPTIC/GRIDS...18
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1156 PM CDT SUN APR 15 2012
.AVIATION...
WEAK DISTURBANCES WILL PUSH ACROSS TONIGHT BEHIND A COLD FRONT WHICH
WILL STALL ALONG THE COASTAL REGIONS. VFR CLOUDINESS WILL CONTINUE OVER
THE I-35 CORRIDOR TAF SITES DUE TO CLOUD DEBRIS BLOWOFF FROM CONVECTION
ALONG THE COASTAL PLAINS. MOSTLY VFR CLEAR KDRT SITE TONIGHT.
ANOTHER DISTURBANCE APPROACHING FROM THE WEST LATE MONDAY AND
MONDAY NIGHT WILL BRING INCREASING MID AND UPPER LEVEL CLOUDINESS
TO THE AREA. I-35 CORRIDOR TERMINALS VARIABLE CLOUDS AOA 6 THSD.
LIGHT NORTH WINDS BECOMING LIGHT NORTHEAST MONDAY. KDRT TERMINAL
VFR CLEAR. KDRT WINDS LIGHT NORTH TONIGHT AND EARLY MONDAY
BECOMING LIGHT EASTERLY BY MIDDAY.
&&
.PREV DISCUSSION... /ISSUED 1139 PM CDT SUN APR 15 2012/
UPDATE...
A BIT SURPRISED BY THE RESURGENCE IN CONVECTION ALONG THE FRONT
OVER THE COASTAL PLAINS...SO WE HAD TO PUT POPS FOR SHOWERS AND
THUNDERSTORMS BACK INTO THE FORECAST FOR THE SOUTHEASTERN
COUNTIES. IT STILL SEEMS MOST OF THE ACTIVITY WILL REMAIN OUTSIDE
OF OUR AREA.
PREV DISCUSSION... /ISSUED 1007 PM CDT SUN APR 15 2012/
UPDATE...
JUST SENT A QUICK GRID AND TEXT UPDATE TO REMOVE POPS IN THE FAR
SOUTHEAST COUNTIES AND RETREND TEMPS...DEW POINTS...AND WINDS
OVERNIGHT. NO MAJOR CHANGES TO THE OVERALL FORECAST.
PREV DISCUSSION... /ISSUED 327 PM CDT SUN APR 15 2012/
DISCUSSION...
THE SFC FRONT IS SLOWLY WORKING ITS WAY INTO THE COASTAL
PLAINS...WITH SCATTERED CONVECTION CONTINUING ALONG THE FRONTAL
BOUNDARY. THE FRONT IS EXPECTED TO STALL ALONG THE COAST LATER
TONIGHT...WITH GOOD CONSENSUS AMONG THE NAM/GFS OF POST-FRONTAL
PRECIPITATION CONTINUING ACROSS OUR SOUTHERN COUNTIES.
HOWEVER...THE 18Z RUC AND 12Z HI-RES BOTH INDICATE THE PRECIP AXIS
WILL SHIFT COMPLETELY SOUTH OF OUR CWA THIS EVENING. HAVE SOMEWHAT
SPLIT THE DIFFERENCE AND KEPT TOKEN POPS ACROSS OUR SOUTHEASTERN
TIER OF COUNTIES FOR THIS EVENING.
AS THE FRONT STALLS ALONG THE COAST OVERNIGHT...THE MID-UPPER
LEVEL TROUGH AXIS WILL REMAIN NORTHWEST OF OUR AREA. THEREFORE
SOME POST-FRONTAL SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP
ACROSS THE SOUTHEASTERN HALF OF THE REGION TOMORROW AND INTO
TOMORROW NIGHT. RAIN CHANCES WILL CLEAR THE AREA ON TUESDAY AS THE
UPPER TROUGH AXIS SLIDES TO THE EAST OF THE REGION AND DRIER NW
FLOW ALOFT SETTLES INTO THE AREA. MOSTLY DRY AND SEASONABLE
CONDITIONS WILL PREVAIL THROUGH THE MIDDLE OF THE WEEK WITH
ONSHORE FLOW RETURNING LATE TUESDAY/EARLY WEDS. THE INCREASING LOW
LEVEL MOISTURE WILL RESULT IN A SLOW WARMING TREND THROUGH THE END
OF THE WEEK.
MID/LONG-RANGE MODELS CONTINUE TO HAVE FAIR CONSENSUS ON AN UPPER
TROUGH/COLD FRONT FOR OUR AREA LATE IN THE WEEK. CURRENT THINKING
IS THAT THE BEST TIME-FRAME FOR RAIN WOULD BE FRI AFTERNOON/NIGHT.
HOWEVER...THIS COULD EASILY SHIFT TO A FRI NIGHT/SAT MORNING OR
LATER SCENARIO GIVEN WE`RE TALKING ABOUT 126-PLUS HRS FROM NOW.
FIRE WEATHER...
ELEVATED TO NEAR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED
ACROSS THE SOUTHERN EDWARDS PLATEAU AND RIO GRANDE PLAINS THROUGH
THIS EVENING IN THE WAKE OF THE COLD FRONT. LOW RELATIVE HUMIDITIES
AND GUSTY NORTHWEST WINDS NEAR 15 MPH WILL CONTINUE THROUGH THE
REMAINDER OF THE AFTERNOON WITH WINDS DECREASING TO 10 TO 15 MPH
AFTER SUNSET. RH VALUES WILL BE SLOWER TO RECOVER. ELEVATED FIRE
WEATHER CONDITIONS ARE EXPECTED ACROSS WESTERN AREAS ON MONDAY
AFTERNOON MAINLY DUE TO LOW HUMIDITIES AS WINDS WILL BE AT OR
BELOW 10 MPH.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 75 54 81 57 82 / 100 - 20 10 -
AUSTIN BERGSTROM INTL AIRPORT 80 52 81 55 82 / 100 - 20 10 -
NEW BRAUNFELS MUNI AIRPORT 82 52 80 56 81 / 80 - 20 10 -
BURNET MUNI AIRPORT 73 49 78 52 80 / 60 - - - 0
DEL RIO INTL AIRPORT 82 51 84 57 86 / 10 - - - 0
GEORGETOWN MUNI AIRPORT 73 49 79 51 81 / 100 - 10 10 -
HONDO MUNI AIRPORT 81 50 81 55 84 / 50 - 20 10 0
SAN MARCOS MUNI AIRPORT 81 53 80 57 81 / 80 - 20 10 -
LA GRANGE - FAYETTE REGIONAL 81 60 80 60 80 / 50 - 40 30 10
SAN ANTONIO INTL AIRPORT 79 54 81 58 82 / 70 - 20 10 -
STINSON MUNI AIRPORT 82 55 81 60 83 / 70 - 20 10 -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...02
SYNOPTIC/GRIDS...26
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1139 PM CDT SUN APR 15 2012
.UPDATE...
A BIT SURPRISED BY THE RESURGENCE IN CONVECTION ALONG THE FRONT
OVER THE COASTAL PLAINS...SO WE HAD TO PUT POPS FOR SHOWERS AND
THUNDERSTORMS BACK INTO THE FORECAST FOR THE SOUTHEASTERN
COUNTIES. IT STILL SEEMS MOST OF THE ACTIVITY WILL REMAIN OUTSIDE
OF OUR AREA.
&&
.PREV DISCUSSION... /ISSUED 1007 PM CDT SUN APR 15 2012/
UPDATE...
JUST SENT A QUICK GRID AND TEXT UPDATE TO REMOVE POPS IN THE FAR
SOUTHEAST COUNTIES AND RETREND TEMPS...DEW POINTS...AND WINDS
OVERNIGHT. NO MAJOR CHANGES TO THE OVERALL FORECAST.
PREV DISCUSSION... /ISSUED 327 PM CDT SUN APR 15 2012/
DISCUSSION...
THE SFC FRONT IS SLOWLY WORKING ITS WAY INTO THE COASTAL
PLAINS...WITH SCATTERED CONVECTION CONTINUING ALONG THE FRONTAL
BOUNDARY. THE FRONT IS EXPECTED TO STALL ALONG THE COAST LATER
TONIGHT...WITH GOOD CONSENSUS AMONG THE NAM/GFS OF POST-FRONTAL
PRECIPITATION CONTINUING ACROSS OUR SOUTHERN COUNTIES.
HOWEVER...THE 18Z RUC AND 12Z HI-RES BOTH INDICATE THE PRECIP AXIS
WILL SHIFT COMPLETELY SOUTH OF OUR CWA THIS EVENING. HAVE SOMEWHAT
SPLIT THE DIFFERENCE AND KEPT TOKEN POPS ACROSS OUR SOUTHEASTERN
TIER OF COUNTIES FOR THIS EVENING.
AS THE FRONT STALLS ALONG THE COAST OVERNIGHT...THE MID-UPPER
LEVEL TROUGH AXIS WILL REMAIN NORTHWEST OF OUR AREA. THEREFORE
SOME POST-FRONTAL SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP
ACROSS THE SOUTHEASTERN HALF OF THE REGION TOMORROW AND INTO
TOMORROW NIGHT. RAIN CHANCES WILL CLEAR THE AREA ON TUESDAY AS THE
UPPER TROUGH AXIS SLIDES TO THE EAST OF THE REGION AND DRIER NW
FLOW ALOFT SETTLES INTO THE AREA. MOSTLY DRY AND SEASONABLE
CONDITIONS WILL PREVAIL THROUGH THE MIDDLE OF THE WEEK WITH
ONSHORE FLOW RETURNING LATE TUESDAY/EARLY WEDS. THE INCREASING LOW
LEVEL MOISTURE WILL RESULT IN A SLOW WARMING TREND THROUGH THE END
OF THE WEEK.
MID/LONG-RANGE MODELS CONTINUE TO HAVE FAIR CONSENSUS ON AN UPPER
TROUGH/COLD FRONT FOR OUR AREA LATE IN THE WEEK. CURRENT THINKING
IS THAT THE BEST TIME-FRAME FOR RAIN WOULD BE FRI AFTERNOON/NIGHT.
HOWEVER...THIS COULD EASILY SHIFT TO A FRI NIGHT/SAT MORNING OR
LATER SCENARIO GIVEN WE`RE TALKING ABOUT 126-PLUS HRS FROM NOW.
FIRE WEATHER...
ELEVATED TO NEAR CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED
ACROSS THE SOUTHERN EDWARDS PLATEAU AND RIO GRANDE PLAINS THROUGH
THIS EVENING IN THE WAKE OF THE COLD FRONT. LOW RELATIVE HUMIDITIES
AND GUSTY NORTHWEST WINDS NEAR 15 MPH WILL CONTINUE THROUGH THE
REMAINDER OF THE AFTERNOON WITH WINDS DECREASING TO 10 TO 15 MPH
AFTER SUNSET. RH VALUES WILL BE SLOWER TO RECOVER. ELEVATED FIRE
WEATHER CONDITIONS ARE EXPECTED ACROSS WESTERN AREAS ON MONDAY
AFTERNOON MAINLY DUE TO LOW HUMIDITIES AS WINDS WILL BE AT OR
BELOW 10 MPH.
&&
.PRELIMINARY POINT TEMPS/POPS...
AUSTIN CAMP MABRY 54 81 57 82 60 / - 20 10 - -
AUSTIN BERGSTROM INTL AIRPORT 52 81 55 82 56 / - 20 10 - -
NEW BRAUNFELS MUNI AIRPORT 52 80 56 81 57 / 20 20 10 - -
BURNET MUNI AIRPORT 49 78 52 80 55 / - - - 0 -
DEL RIO INTL AIRPORT 51 84 57 86 63 / - - - 0 -
GEORGETOWN MUNI AIRPORT 49 79 51 81 56 / - 10 10 - -
HONDO MUNI AIRPORT 50 81 55 84 58 / - 20 10 0 -
SAN MARCOS MUNI AIRPORT 53 80 57 81 58 / - 20 10 - -
LA GRANGE - FAYETTE REGIONAL 60 80 60 80 60 / 20 40 30 10 -
SAN ANTONIO INTL AIRPORT 54 81 58 82 60 / - 20 10 - -
STINSON MUNI AIRPORT 55 81 60 83 60 / - 20 10 - -
&&
.EWX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MESOSCALE/AVIATION...02
SYNOPTIC/GRIDS...26
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1104 PM CDT SUN APR 15 2012
UPDATED FOR SHORT-TERM FCST TRENDS AND 06Z TAF ISSUANCE
.UPDATE...NEEDED TO BACKTRACK A LITTLE ON THE EARLIER REDUCTION IN
POPS. SCT SHRA/ISOLD TSRA DEVELOPING ACRS MUCH OF THE FCST AREA
NOW AS VERY STG QG FORCING WITH THE MAIN UPR SYSTEM SWINGS ACRS
THE AREA. WL CARRY IN THE GRIDS/ZONES FOR MOST AREAS AS SCT
SHRA/ISOLD TSRA WITH GUSTY WINDS.
NO CHG TO THINKING ON WIND POTENTAIL FOR THE REST OF THE NGT. VERY
STG WINDS NOT TOO FAR OFF THE SFC COULD GET CARRIED DOWN IN SPOTS
BY PCPN...AND RESULT IN LOCALIZED WIND DAMAGE. THAT THREAT WL
REMAIN FOR MUCH OF THE REST OF THE NGT...THOUGH WINDS ALOFT WL
START TO SLOWLY DECR FM W TO E AFTER MIDNIGHT.
SLOWER MVMT OF SFC LOW WL ALSO KEEP WARM TEMPS ARND MOST OF THE
NGT. RAISED MINS MOST AREAS...AND MINS WL PROBABLY OCCUR ARND
15Z...RIGHT AT THE END OF MIN TEMP FCST PERIOD. TEMPS WL PROBABLY
CONT TO FALL MON AS COLDER AIR FLOODS IN FM THE NW.
SKOWRONSKI
&&
.PREV DISCUSSION...ISSUED AT 854 PM CDT SUN APR 15 2012...
UPDATE...THE SITN FOR THE REST OF THE NIGHT STARTING TO BECOME
CLEARER. STRONGEST SFC PRESSURE GRADIENT SHIFTG E OF THE AREA NOW.
THAT COMBINED WITH SLIGHT STABILIZATION OF THE BOUNARY LAYER
SHOULD SOON CUT DOWN ON ANY MIXING INTO STRONGER WINDS ALOFT
OUTSIDE OF RAIN AREAS...AND RESULT IN A DECR IN THE GUSTS THAT
HAVE BEEN OCCURRING OVER THE SRN PART OF THE FCST AREA THE PAST
FEW HRS.
THE POTENTIAL FOR GUSTS WITHIN RAIN SHAFTS STILL IN QUESTION.
NARROW BAND OF SHRA/TSRA OUT NEAR THE MISSISSIPPI HAS BEEN GETTING
BETTER ORGANIZED WITHIN THE PAST HR. THAT WL STILL POSE SOME RISK
OF STRONGER GUSTS WHEN IT WORKS EWD LATER TNGT. 850 MB FLOW
PROGGED BY THE RUC TO PEAK AT 60-70KTS THE NEXT FEW HRS...THEN
DECR FM WEST TO EAST...POSSIBLY BEFORE THE PCPN ARRIVES. NO SVR
GUSTS OCCURRING WITH THE LINE NOW NOR HAVE THERE BEEN THIS
EVENING. BUT THE LINE IS ALMOST PARALLEL TO THE LOW-LVL WINDS
NOW...AND WL BECOME AT LEAST A LITTLE MORE NORMAL TO THE WINDS BY
THE TIME IT REACHES OUR AREA LATER IN THE NGT. THE BOTTOM LINE IS
IT/S PROBABLY GOING TO BE IMPOSSIBLE TO COME OUT WITH AN ALL-CLEAR
TYPE STATEMENT. BASED ON HOW THINGS LOOK NOW...WL PROBABLY END UP
NEEDING TO KEEP ALIVE AT LEAST THE POSSIBILITY OF ISOLD STG GUSTS.
WL BE DOING A MORE COMPREHENSIVE FCST UPDATE WITHIN THE
NEXT HR AS NEED TO LOOK AT PLACEMENT/TIMING OF POPS THE REST OF
THE NGT. WL GET UPDATE OUT ASAP...BUT PROBABLY A LITTLE LATER THAN
I/D NORMALLY LIKE.
SKOWRONSKI
DISCUSSION ISSUED AT 753 PM CDT SUN APR 15 2012...
UPDATE...HAVE BEGUN TO PULL BACK ON SVR WORDING/HILIGHTING IN THE
FCST PRODUCTS. THIS IS TRICKY BECAUSE THE THREAT HAS NOT
ENDED...BUT VERY LIMITED DESTABILIZATION SEEMS TO REALLY BE
HOLDING THINGS BACK. SFC DWPTS BACK IN W-C WI HAVE ACTUALLY EDGED
BACK A BIT AS THERE WAS MIXING INTO DRIER AIR ALOFT. LOCAL MESO
PLOTS CLEARLY SHOW SBCAPE AND MLCAPES DECRG DURING THE PAST
SEVERAL HOURS. IT REALLY SEEMS LIKE THE MAIN THREAT IS GOING TO BE
MIXING OF STRONGER GRADIENT WINDS DOWN TO THE SFC WITH PCPN. BUT
IN ORDER FOR THAT TO HAPPEN...WE/VE GOT TO GET PCPN GOING IN THE
FCST AREA. AND THAT CONTINUES TO BE VERY SLOW TO HAPPEN.
THE STRONGEST WINDS WE/VE HAD THUS FAR HAVE ACTUALLY BEEN OUTSIDE
OF PCPN AREAS. SOME LATE-DAY SUN BACK IN CENTRAL WI ALLOWED ENOUGH
SFC-BASED DESTABILIZATION TO MIX INTO STRONGER WINDS ALOFT...AND
RESULTED IN SOME GUSTS APPROACHING 40 KTS. THAT MAY CONT INTO THE
EVENING...THOUGH IT WL BE TOUGHER TO MAINTAIN THE NECESSARY VERY
STEEP LOW-LEVEL LAPSE RATES AFTER DARK.
SKOWRONSKI
DISCUSSION ISSUED AT 619 PM CDT SUN APR 15 2012...
UPDATE...CONVECTIVE TRENDS STILL NOT EASY TO GET A GRASP ON WITH
ANY CONFIDENCE. PCPN CURRENTLY GOING ARND THE FCST AREA...WITH
CELLULAR DEVELOPMENT NEAR THE UPPER SYSTEM LIFTG NWD ACRS
MN/IA/FAR NW WI. LARGE BAND OF SHRA/TSRA STREAMING NE FM MO WAS
CLIPPING THE SE PART OF THE FCST AREA AT TIMES...BUT MOST OF THE
STORMS IN THAT AREA DIDN/T APPEAR TO BE ANYTHING SPECIAL. LOOKS
LIKE A MORE ORGANIZED LINE MAY BE TAKING SHAPE FM IRK-W OF
STL...BUT EXTRAPOLATING THE MVMT OF THAT LINE WOULD KEEP IT SE OF
THE AREA. SO...WE ARE IN A HOLDING PATTERN. MAY NEED TO WAIT FOR
THE WRN STORMS TO SHIFT EWD...BUT THAT WON/T HAPPEN ANY TIME
SOON. THE OTHER OPTION IS FOR NEW STORMS TO FILL-IN BTWN THE TWO
AREAS OF PCPN OUT THERE NOW. THAT MAY BE HELD BACK SOME BY UPR DRY
SLOT...AND THE RGN BEING IN RFQ OF STG UPPER SPEED MAX. GIVEN THE
VERY STG SHEAR IN PLACE...IT/S GOING TO BE TOUGH TO GIVE UP ON THE
THREAT EVEN WITH WHAT WOULD NORMALLY BE ONLY MARGINAL INSTABILITY
IN PLACE. THE STG SHEAR WOULD ALSO MAINTAIN A SVR THREAT LATER
INTO THE NGT THAN WOULD NORMALLY BE THE CASE.
SKOWRONSKI
DISCUSSION ISSUED AT 316 PM CDT SUN APR 15 2012...
SHORT TERM...TNGT AND MON. MAIN FCST ISSUE REMAINS THE SVR THREAT
ACROSS THE FCST AREA THIS EVENING. OTHER POTENTIAL PROBLEMS
INCLUDE: POTENTIAL DRY SLOT ENDING PCPN OVER PARTS OF NE WI LATER
TONIGHT AND TEMPS ON MON.
THE 20Z MSAS SFC ANALYSIS SHOWED AN AREA OF LOW PRES CENTERED OVER
EAST-CENTRAL NEBRASKA WITH A WRMFNT EXTENDED E-NE THRU SRN MN INTO
CENTRAL WI. A CDFNT STRETCHED SOUTHWARD FROM THE LOW THRU THE
CENTRAL PLAINS. VISIBLE SATL IMAGERY INDICATED CLEARING SKIES OVER
MUCH OF IA WITH CUMULUS CLOUDS STARTING TO GROW ACROSS WRN IA.
RADAR MOSAIC DID SHOW SOME NON-SEVERE CONVECTION OVER SE WI HEADED
TOWARD LK MI.
A SHORTWAVE TROF OVER THE CENTRAL PLAINS IS FCST TO LIFT NEWD INTO
THE UPR MS VALLEY REGION TNGT. THE ASSOCIATED SFC LOW WL TRACK NE
AND REACH CENTRAL SECTIONS OF UPR MI BY DAYBREAK. THE WRMFNT WL
CONT TO SLOWLY LIFT NORTH TOWARD NRN WI THIS EVENING...WITH THE
TRAILING CDFNT FROM THE LOW PRES PUSHING EAST INTO CENTRAL WI WELL
AFTER MIDNIGHT. ANTICIPATE CONVECTION TO FIRE ACROSS MN/IA LATE
THIS AFTERNOON AS SUFFICIENT MSTR (DEW PTS IN THE 60S)...INSTABILITY
(CAPES > 1K J/KG...SUB-ZERO LI`S) AND LIFT FROM A NEARLY COUPLED JET
STRUCTURE...CDFNT) ALL INTERACT TO QUICKLY ALLOW TSTMS TO FORM.
THESE STORMS WL LIKELY TURN SEVERE AND HEAD E-NE INTO WI THIS
EVENING BEFORE WEAKENING/DISSIPATING OVERNIGHT. MDLS ACTUALLY DRY
SLOT MUCH OF NE WI DURING THE OVERNIGHT PERIOD...THUS THE MAJORITY
OF THE SEVERE WEATHER WL BE TO OUR WEST WITH PRIMARILY GUSTY WINDS
ACCOMPANYING ANY TSTM ACTIVITY. HAVE LEFT PCPN AS RAIN...ALTHO
COLDER AIR FILTERING INTO NORTH-CENTRAL WISCONSIN LATE COULD MIX A
FEW WET SNOWFLAKES WITH THE RAIN.
WEAKENING SHORTWAVE TROF/SFC LOW CROSS NORTHERN SECTIONS OF THE
GREAT LKS MON MORNING WITH THE CDFNT COMPLETING ITS PASSAGE THRU
ERN WI. COLDER AIR AND WRAP-AROUND MOISTURE WL OVERSPREAD THE FCST
AREA WITH NEARLY STEADY OR SLOWLY FALLING TEMPS AND SCATTERED RAIN
OR SNOW SHOWERS THRU THE DAY. THERE WL BE A MINOR ACCUMULATION
ACROSS THE NORTH (LESS THAN AN INCH)...MAINLY ON GRASSY SURFACES.
LASTLY...A BLUSTERY DAY ON TAP WITH WIND GUSTS TO 30 MPH POSSIBLE
AS THE PRES GRADIENT IS TIGHT BETWEEN THE LOW PRES OVER SE ONTARIO
AND INCOMING HI PRES OVER THE UPR MS VALLEY.
LONG TERM...MONDAY NIGHT THROUGH NEXT SUNDAY. MAIN UPPER SYSTEM
WITH WRAP AROUND MOISTURE TO EXIT NORTHEAST WISCONSIN MONDAY
NIGHT. TRAILING WEAK SHORT WAVE TROUGH MONDAY NIGHT MAY TEND TO
KEEP A FEW CLOUDS AROUND SO WILL CONTINUE WITH A OVERNIGHT CLEARING
TREND AS A HIGH PRESSURE RIDGE DRIFTS TOWARD THE STATE AND UPPER
PATTERN FLATTENS TO A ZONAL FLOW. OTHERWISE A COLD NIGHT IN STORE
DUE TO THE RATHER COOL START FROM MONDAY AFTERNOON.
NEXT PCPN CHC ASSOCIATED WITH A NORTHERN STREAM WAVE WITH FRONTAL
SYSTEM APPROACHING FROM THE NORTHERN PLAINS TOWARD WEDNESDAY.
LATEST TRENDS SUGGEST A TIMING OF CENTRAL AND NORTH CENTRAL LATE
TUESDAY NIGHT BEFORE EXITING EASTERN WISCONSIN WEDNESDAY EVENING.
SYSTEM WILL BE ON THE NOSE OF A 80 KNOT UPPER JET BUT WAA PATTERN
SUPPORTS ELEVATED CONVECTION...AT LEAST EARLY IN THE EVENT AND
OVER MAINLY NORTHERN WISCONSIN...WITH FURTHER CONVECTION LIKELY
ALONG THE COLD FRONT LATER WEDNESDAY.
MODELS DIVERGE WITH SOLUTIONS FOR THE THURSDAY NIGHT INTO FRIDAY
PERIOD. ECMWF MORE NORTH AND STRONGER WITH A SURFACE LOW TRACKING
OVER SOUTHERN WISCONSIN WHILE THE GFS IS FURTHER SOUTH. BOTH
MODELS PROG A STRONG H8 LOW ALONG A BAROCLINIC ZONE FOR A NICE QPF
EVENT...JUST LOCATION IS QUESTIONABLE. WILL CONTINUE A BLEND FOR
THIS PACKAGE.
UPPER HEIGHTS BUILD FOR NEXT WEEKEND FOR A MAINLY DRY FORECAST AT
THIS TIME.
&&
.AVIATION...MAIN CHG FOR THE 06Z TAF PKG WAS TO INCR LLWS WITH
VERY STG WINDS JUST ABV THE SFC. ALSO SLOWED THE SHIFT TO NWLY
WINDS BEHIND THE SYSTEM TOMORROW.
SKOWRONSKI
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
751 AM EDT MON APR 16 2012
.SYNOPSIS...
ISSUED AT 556 AM EDT MON APR 16 2012
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW POTENT SHRTWV/H5
CLOSED LO LIFTING NEWD INTO MN ON NW FLANK OF SHARP RDG OVER THE SE
CONUS...WITH OCCLUDED SFC LO NOT FAR FM MPX AT 03Z. WARM FNT
EXTENDING E FM THIS FEATURE CROSSES NRN WI TO JUST S OF MNM AND
SEPARATES SFC T/TD ARND 70/60 FM T/TD IN THE 40S AND 50S OVER UPR
MI. SLOW WARMING HAS GRADUALLY ERODED SOME LOCALLY DENSE FOG THAT
WAS PRESENT EARLIER OVER THE CWA. DRY SLOTTING ALF E OF THE SHRTWV
HAS INVADED THE CWA/MUCH OF WI...WITH SOME SHRA/TS OVER LK SUP JUST
N OF THE H85 WARM FNT WHERE H7-6 FGEN IS SHARPEST. SOME ISOLD SHRA
ARE LOCATED OVER WI S OF THE WARM FNT. HEAVIER/MORE WIDESPREAD
SHRA/TS ARE PRESENT OVER ERN WI/LK MI WITHIN THE WARM CONVEYOR BELT
MSTR TO THE E OF THE DRY SLOT THAT WL ALSO MISS UPR MI TO THE E. TO
THE NW...WELL DEFINED CCB IS PRESENT FM NRN MN EXTENDING INTO THE
ERN DAKOTAS ON THE CYC SIDE OF H5 LO TRACK. A BAND OF SHRA/SOME TS
IS PRESENT EXTENDING FM NW WI TO FAR SE MN ON THE WRN EDGE OF DRY
SLOT/IN ADVANCE OF APRCHG UPR LO...WHERE SPC MESOANALYSIS INDICATES
MUCAPE ARND 500 J/KG TO THE S OF SFC WARM FNT. DESPITE SOME SHARP
H7-3 QVECTOR CNVGC/DIFFLUENT UPR FLOW IN EXIT REGION OF SUPPORTING
120KT H3 JET MAX/HGT FALLS AHEAD OF THIS FEATURE/SFC-6KM BULK SHEAR
UP TO 70 KTS...THE TS HAVE NOT INTENSIFIED AS THE LINE OF SHRA MOVES
E INTO WI EVEN THOUGH THERE HAVE BEEN SOME WIND GUSTS UP TO 40 KTS
OBSVD WHERE THE CONVECTION IS SFC BASED IN THE WARM SECTOR. MODERATE
RA IS FALLING IN THE COLDER AIR OVER MUCH OF NRN MN UNDER THE
SHARPLY NNE CYC FLOW TO THE N AND NW OF THE SFC LO...WITH N WIND
GUSTS 30-40 KTS. SN HAS MIXED IN WITH THE PCPN OVER NRN MN AS THESE
STRONG WINDS HAVE DRAWN COLDER AIR TO THE S. THE 00Z H85 WIND AT
ABERDEEN SDAKOTA WAS 75 KTS. 02Z NE WIND GUSTS DOWN THE W END OF LK
SUP REACHED 44 MPH AT ASX IN NW WI. NO SN IS FALLING UNDER THIS AREA
AS OF MIDNGT...BUT MUCH COLDER AIR LURKS JUST TO THE N...WITH 00Z
H85 TEMP -11C AT YPL.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 556 AM EDT MON APR 16 2012
MAIN FCST CONCERNS FOR TODAY INTO TNGT ARE POPS/PTYPE/POTENTIAL FOR
STRONG WINDS ASSOCIATED WITH CCB THAT WL SHIFT ACRS UPR MI AS THE
SHRTWV/SFC LO MOVES TO THE E.
TODAY...SFC LO IS PROGGED TO MOVE TO SE LK SUP/ERN UPR MI BY 18Z
BEFORE CONTINUING INTO QUEBEC BY 00Z. SINCE THE SHRTWV WL BE MOVING
INTO A ZONE OF UPR CONFLUENCE BTWN THE BASE OF UPR TROF CENTERED
NEAR HUDSON BAY AND UPR RDG IN THE SE CONUS...THE SHRTWV/SFC LO ARE
EXPECTED TO WEAKEN...ESPECIALLY THIS AFTN. EVEN SO...TIGHT PRES
GRADIENT/SHARP NLY FLOW ON THE WRN FLANK OF THE DEPARTING LO ARE
FCST TO ADVECT MUCH COLDER AIR LURKING TO THE N INTO THE UPR LKS.
EXPECT INCRSG POPS OVER THE W BY SUNRISE TO SPREAD EWD WITH THE
DEEPER MSTR UNDER THE CCB. FCST SDNGS STILL SHOW SOME SHARP COOLING
BLO ELEVATED WARM LYR...SO WL RETAIN MENTION OF SLEET IN THE
TRANSITION BTWN ALL RA AND MORE SN ONCE DEEPER COLD AIR ARRIVES OVER
THE W BY AFTN. BUT STRONG CAD/WEAKENING UPR DVGC AS JET CORE SHIFTS
TO THE NE WL TEND TO CAUSE THE CCB TO DECAY A BIT AS LARGER SCALE
QVECTOR DVGC DVLPS OVER THE CCB. ALTHOUGH FCST H85 TEMPS FALLING AS
LO AS -13C TO -15C BY 00Z COULD ADD SOME LK ENHANCED COMPONENT INTO
THE PCPN FIELD...WEAKENING DYNAMICS SHOULD LIMIT THIS POTENTIAL WITH
THE COLDEST AIR ARRIVING ONLY AFT 18Z ONCE LARGER SCALE QVECTOR DVGC
DOMINATED BY THE CAD IS IN PLACE. SO EXPECT SN ACCUMS TO BE SUB
ADVY. THE ARRIVAL OF THE COLDER AIR WL SHARPEN LLVL INSTABILITY AND
AID MIXING OF H925 WINDS UP TO 35 TO 45 KTS. ALTHOUGH THE APRCH FM
THE WSW OF THE SHARP PRES RISE CENTER WL RESULT IN ISALLOBARIC WIND
COMPONENT AT A RIGHT ANGLE OR EVEN OPPOSING THE GRADIENT FLOW AND
THE LO WL BE WEAKENING WITH TIME... THE MAGNITUDE OF THE GRADIENT
WIND IN CONCERT WITH FAVORABLE MIXING UNDER THE INCOMING THERMAL
TROF JUSTIFY ISSUANCE OF HI WIND ADVYS FOR EXPOSED LOCATIONS NEAR
THE LK SUP SHORE.
TNGT...AS HI PRES BLDS INTO THE WRN CWA OVERNGT...THE PRES GRADIENT
WL DIMINISH QUICKLY FOLLOWING PASSAGE OF PRES RISE CENTER TO THE E
AFT 00Z. SO EXPECT GUSTY WINDS TO DIMINISH QUICKLY THIS EVNG INTO
THE OVERNGT. BUMPED POPS UP TO LIKELY IN AREAS E OF MQT WITH H85
THERMAL TROF/TEMPS AS LO AS -13C TO -15C CONDUCIVE FOR SOME LES IN
MOIST CYC NW FLOW. SUBSIDENCE DROPPING INVRN AOB 3K FT/RISING H85
TEMPS/WEAKENING CYC FLOW OVERNGT WL CAUSE ANY SHSN TO DIMINISH
STEADILY AFT MIDNGT. CONSIDERING THE CHILL OF THE INCOMING
AIRMASS...PWAT FALLING BLO 0.25 INCH...AND THE PROSPECT OF CLRG OVER
THE INTERIOR W AS HI PRES BLDS OVHD...TENDED TO GO LOWER THAN
PREVIOUS FCST FOR MIN TEMPS IN THAT AREA.
TUE...HUDSON BAY HI PRES/DRY AIRMASS WL DOMINATE UPR MI...BRINGING
RELATIVELY DRY AND TRANQUIL WX. ALTHOUGH THERE WL BE SOME LINGERING
SC OVER MAINLY THE E HALF IN THE MRNG WITH LINGERING LIGHTER CYC
FLOW/LLVL MSTR/THERMAL TROF UNDER SUBSIDENCE INVRN...THIS CLD SHOULD
DISSOLVE BY AFTN WITH ARRIVAL OF SFC HI PRES RDG/ACYC FLOW AND
DAYTIME HEATING...GIVING WAY TO JUST SOME DIURNAL CU. MIXING TO H85
ON GFS FCST SDNGS WOULD YIELD HI TEMPS RANGING FM ARND 40 AT ERY TO
50 NEAR THE WI BORDER...BUT THE DAY WL BE COOLER NEAR THE MODIFYING
INFLUENCE OF THE LKS AS WEAK PRES GRADIENT IN THE AFTN WL ALLOW FOR
LK BREEZE DEVELOPMENT.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 556 AM EDT MON APR 16 2012
MUCH OF LONGER RANGE PORTION OF FCST IS DOMINATED BY NEGATIVE UPPER
AIR ANAMOLIES STATIONED OVER NORTHEAST PACIFIC OCEAN/GULF OF ALASKA
AND OVR HUDSON BAY INTO NUNAVUT CANADA. ZONAL FLOW FCST TO IMPACT
CONUS MUCH OF THE WEEK AND INTO NEXT WEEKEND AS WELL.
ATTM ONLY ONE SYSTEM IS SURE THING TO IMPACT THE AREA IN THE LONGER
TERM. THIS IS STILL OPEN TO CHANGE DEPENDING ON TRACK OF LATE WEEK
SYSTEM.
SHORTWAVE ON SOUTHERN EDGE OF TROUGH OVR NORTHEAST PACIFIC/GULF OF
ALASKA FCST TO SLIDE ACROSS ROCKIES INTO NORTHERN PLAINS ON TUESDAY
NIGHT AND PUSH ACROSS UPPER GREAT LAKES ON WEDNESDAY. SW WINDS AHEAD
OF SFC-H85 TROUGH BRINGS MUCH WARMER/MOIST AIR INTO UPR LAKES IN WAKE
OF THE EARLY WEEK CHILL. JET STREAKS SLIDING ACROSS THE NORTHERN
PLAINS AND OVR ONTARIO SHOULD HELP SYSTEM STAY FAIRLY ORGANIZED AS
IT CROSSES CWA ON WEDNESDAY. APPEARS THAT SYSTEM WILL BE COMPACT AS
IT MOVES THROUGH...LEADING TO A FAIRLY STRONG WIND FIELD IN THE
VCNTY. HAVE INCREASED WINDS ESPECIALLY IN THE WAKE OF THE LOW LATE
WEDNESDAY INTO WEDNESDAY NIGHT NEAR LAKE SUPERIOR.
PTYPE MAY BE ISSUE INITIALLY WITH SNOW OR EVEN FREEZING RAIN
POSSIBLE INTERIOR CNTRL /10Z-12Z ON WEDNESDAY/ AS SWATH OF
PRECIPITATION ARRIVES OVER PERSISTENT SHALLOW COLD AIR. ANY WINTRY
PRECIP SHOULD BE BRIEF THOUGH AS STRONG WARM AIR ADVECTION SFC-H85
QUICKLY BECOMES DOMINANT. ADDED TSRA FOR WEDNESDAY AS WELL DUE TO
STEEP H7-H5 LAPSE RATES AOA 8C/KM. PRETTY DYNAMIC SYSTEM LOOKS TO
AFFECT THE AREA. GIVEN CONVECTIVE POTENTIAL MAY SEE RAIN TOTALS OVR
0.25 INCH IN SOME AREAS. STILL SOME POTENTIAL FOR SNOW AS SYSTEM
EXITS ON WEDNESDAY NIGHT. 850MB/925MB TEMPS AS LOW AS -10C/-6C STILL
LEAVES POTENTIAL FOR BRIEF LAKE ENHANCED SNOW OVR HIGHER TERRAIN OF
WEST CWA IF ENOUGH MOISTURE REMAINS IN PLACE. JUST LOW CHANCE POPS
FOR NOW.
IN THE EXTENDED...FRIDAY SYSTEM IS BACK ON FOR AT LEAST THE
SOUTHEAST QUARTER OF THE CWA...AT LEAST ACCORDING TO ECMWF AND
CANADIAN. ECMWF HAS SHOWN THIS OFF AND ON FOR LAST FEW DAYS AND
LATEST GFS HAS TRENDED NORTH...THOUGH IS STILL MAINLY SOUTH OF CWA
WITH ITS AXIS OF MAX QPF. SINCE SFC LOW IS STILL FCST TO PASS MAINLY
OVR CNTRL GREAT LAKES EVEN ON THE ECMWF...PCPN IF IT OCCURS WOULD
LIKELY STAY MAINLY IN FORM OF SNOW. ECMWF WOULD POINT TO SEVERAL
INCHES OF ACCUMULATION OVR SE CWA JUST NORTH OF H85-H7 LOW TRACK.
SYSTEM IS STILL NEAR THE ALLUTIANS IN THE PACIFIC SO EXPECT MORE
JUMPING AROUND ON THE POSITION OF THE LOW YET THIS WEEK. SOMETHING
TO DEFINITELY KEEP AN EYE ON THOUGH.
BEYOND FRIDAY APPEARS DRY WEATHER IS IN STORE FOR NEXT WEEKEND. WILL
NOT BE ESPECIALLY WARM THOUGH AS LARGER SCALE TROUGH RESIDES OVR
MUCH OF EASTERN CANADA AND EASTERN CONUS. SFC-H85 RIDGE WILL BE
OVERHEAD LEADING TO LIGHT WINDS/LK BREEZES. BEST CHANCE FOR DAYTIME
TEMPS AT LEAST NEAR NORMAL WILL BE WELL INLAND FM THE LAKES TOWARD
WISCONSIN BORDER. COULD ALSO BE CHILLY NIGHTS AS WELL...WITH TEMPS
POSSIBLY IN THE TEENS AND 20S. EXPECT RELATIVE HUMIDITIES TO BE ON
THE LOW SIDE FOR THE WEEKEND AS WELL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 747 AM EDT MON APR 16 2012
COMPLICATED FORECAST OVER THE NEXT 12 HOURS AS LOW PRESSURE SYSTEM
MOVES ACROSS UPPER MICHIGAN AND MUCH COLDER AIR PUSHES INTO THE
REGION.
KIWD AND KCMX...CONDITIONS WILL REMAIN NEAR ALT LANDING MINS THROUGH
EARLY AFTN AS FLOW BCMS ONSHORE AND NERLY. COLD ADVECTION BEHIND
FRONT WILL TURN SHRA TO SN AND PL BY MID MORNING AS NORTH WINDS GUST
FM OVER 30 KTS. EXPECT CONDITIONS TO IMPROVE TO MVFR BY THIS EVENING
AS RIDGE BUILDING IN WILL KNOCK DOWN WINDS AND BRING IN DRIER AIR.
KSAW...EXPECT VFR CIGS AND POSSIBLE MVFR VSBY AS SOME SHRA MOVE
THROUGH THIS MORNING. WINDS WILL SHIFT NW AND BECOME GUSTY AOA 30
KTS BEHIND COLD FRONT BY EARLY AFTN WITH SHRA CHANGING TO SHSN
ALTHOUGH EXPECT GENERALLY MVFR CONDITIONS. RIDGING FM THE WEST
WILL DIMINISH WINDS LATER THIS EVENING AS BRIEF PERIOD OF LAKE
ENHANCED SNOW ENDS. MVFR CLOUDS WILL REMAIN THROUGH OVERNIGHT
HOURS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 556 AM EDT MON APR 16 2012
CONSIDERING A NUMBER OF OBS SHOWING WIND GUSTS UP TO 50 KTS OVER THE
W HALF WHERE TERRAIN ENHANCES THE PREVAILING NE FLOW EARLY THIS
MRNG...OPTED TO ISSUE STORM WARNINGS FOR THE 3 WESTERN ZONES OF LAKE
SUPERIOR. AS THE FLOW BACKS TO N...EXPECT THE WINDS TO SUBSIDE A BIT
WITH JUST N GALES THRU THE AFTN AS THE ARRIVAL OF MUCH COLDER
ENHANCES MIXING OF HIER MOMENTUM TO THE LAKE SURFACE. EVEN THESE
WINDS WILL TEND TO DIMINISH OVER THE FAR W LATER IN THE DAY WITH
APPROACH OF HI PRES RIDGE. LINGERING GALES WILL END OVER THE REST OF
THE LAKE AS THE HI PRES RIDGE/WEAKER PRES GRADIENT DOMINATES THE
LAKE.
NEXT LOW PRES SYSTEM FCST TO MOVE THRU THE UPPER LAKES WED IS NOW
LOOKING STRONGER. EXPECT SOUTHERLY WINDS TO 30 KTS WEDNESDAY MORNING
TO SHIFT TO THE WEST AND INCREASE TO GALES ESPECIALLY OVER THE EAST
HALF OF THE LAKE BY LATER WEDNESDAY AFTN AND INTO THE EARLY EVENING.
WINDS DIMINISH BLO 25 KTS LATER WEDNESDAY NIGHT INTO THURSDAY AS
HIGH PRESSURE MOVES BACK OVR THE UPR LAKES REGION. SFC LOW PASSING
BY ACROSS THE CNTRL GREAT LAKES THURSDAY NIGHT INTO FRIDAY COULD
RESULT IN NORTHEAST WINDS 25-30 KTS OVR SOUTHERN PORTIONS OF LK
SUPERIOR.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR MIZ002-003.
WIND ADVISORY UNTIL 8 PM EDT THIS EVENING FOR MIZ001.
WIND ADVISORY FROM 5 PM THIS AFTERNOON TO 11 PM EDT THIS EVENING
FOR MIZ006-007.
WIND ADVISORY FROM 2 PM THIS AFTERNOON TO 8 PM EDT THIS EVENING
FOR MIZ005.
LAKE SUPERIOR...
GALE WARNING FROM 5 PM THIS AFTERNOON TO 2 AM EDT TUESDAY FOR
LSZ251-267.
GALE WARNING FROM 11 AM THIS MORNING TO 2 AM EDT TUESDAY FOR
LSZ266.
GALE WARNING FROM 11 AM THIS MORNING TO 8 PM EDT THIS EVENING
FOR LSZ265.
STORM WARNING UNTIL 2 PM EDT THIS AFTERNOON FOR LSZ263-264.
GALE WARNING FROM 2 PM THIS AFTERNOON TO 8 PM EDT THIS EVENING
FOR LSZ248-263-264.
GALE WARNING FROM 2 PM THIS AFTERNOON TO 2 AM EDT TUESDAY FOR
LSZ249-250.
GALE WARNING UNTIL 8 PM EDT THIS EVENING FOR LSZ242>245.
GALE WARNING UNTIL 2 PM EDT /1 PM CDT/ THIS AFTERNOON FOR LSZ240-
241.
STORM WARNING UNTIL 8 AM EDT /7 AM CDT/ THIS MORNING FOR LSZ162.
GALE WARNING UNTIL 2 PM EDT /1 PM CDT/ THIS AFTERNOON FOR LSZ162.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...KC
SHORT TERM...KC
LONG TERM...JLA
AVIATION...JLA
MARINE...KC/JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
558 AM EDT MON APR 16 2012
.SYNOPSIS...
ISSUED AT 556 AM EDT MON APR 16 2012
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW POTENT SHRTWV/H5
CLOSED LO LIFTING NEWD INTO MN ON NW FLANK OF SHARP RDG OVER THE SE
CONUS...WITH OCCLUDED SFC LO NOT FAR FM MPX AT 03Z. WARM FNT
EXTENDING E FM THIS FEATURE CROSSES NRN WI TO JUST S OF MNM AND
SEPARATES SFC T/TD ARND 70/60 FM T/TD IN THE 40S AND 50S OVER UPR
MI. SLOW WARMING HAS GRADUALLY ERODED SOME LOCALLY DENSE FOG THAT
WAS PRESENT EARLIER OVER THE CWA. DRY SLOTTING ALF E OF THE SHRTWV
HAS INVADED THE CWA/MUCH OF WI...WITH SOME SHRA/TS OVER LK SUP JUST
N OF THE H85 WARM FNT WHERE H7-6 FGEN IS SHARPEST. SOME ISOLD SHRA
ARE LOCATED OVER WI S OF THE WARM FNT. HEAVIER/MORE WIDESPREAD
SHRA/TS ARE PRESENT OVER ERN WI/LK MI WITHIN THE WARM CONVEYOR BELT
MSTR TO THE E OF THE DRY SLOT THAT WL ALSO MISS UPR MI TO THE E. TO
THE NW...WELL DEFINED CCB IS PRESENT FM NRN MN EXTENDING INTO THE
ERN DAKOTAS ON THE CYC SIDE OF H5 LO TRACK. A BAND OF SHRA/SOME TS
IS PRESENT EXTENDING FM NW WI TO FAR SE MN ON THE WRN EDGE OF DRY
SLOT/IN ADVANCE OF APRCHG UPR LO...WHERE SPC MESOANALYSIS INDICATES
MUCAPE ARND 500 J/KG TO THE S OF SFC WARM FNT. DESPITE SOME SHARP
H7-3 QVECTOR CNVGC/DIFFLUENT UPR FLOW IN EXIT REGION OF SUPPORTING
120KT H3 JET MAX/HGT FALLS AHEAD OF THIS FEATURE/SFC-6KM BULK SHEAR
UP TO 70 KTS...THE TS HAVE NOT INTENSIFIED AS THE LINE OF SHRA MOVES
E INTO WI EVEN THOUGH THERE HAVE BEEN SOME WIND GUSTS UP TO 40 KTS
OBSVD WHERE THE CONVECTION IS SFC BASED IN THE WARM SECTOR. MODERATE
RA IS FALLING IN THE COLDER AIR OVER MUCH OF NRN MN UNDER THE
SHARPLY NNE CYC FLOW TO THE N AND NW OF THE SFC LO...WITH N WIND
GUSTS 30-40 KTS. SN HAS MIXED IN WITH THE PCPN OVER NRN MN AS THESE
STRONG WINDS HAVE DRAWN COLDER AIR TO THE S. THE 00Z H85 WIND AT
ABERDEEN SDAKOTA WAS 75 KTS. 02Z NE WIND GUSTS DOWN THE W END OF LK
SUP REACHED 44 MPH AT ASX IN NW WI. NO SN IS FALLING UNDER THIS AREA
AS OF MIDNGT...BUT MUCH COLDER AIR LURKS JUST TO THE N...WITH 00Z
H85 TEMP -11C AT YPL.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 556 AM EDT MON APR 16 2012
MAIN FCST CONCERNS FOR TODAY INTO TNGT ARE POPS/PTYPE/POTENTIAL FOR
STRONG WINDS ASSOCIATED WITH CCB THAT WL SHIFT ACRS UPR MI AS THE
SHRTWV/SFC LO MOVES TO THE E.
TODAY...SFC LO IS PROGGED TO MOVE TO SE LK SUP/ERN UPR MI BY 18Z
BEFORE CONTINUING INTO QUEBEC BY 00Z. SINCE THE SHRTWV WL BE MOVING
INTO A ZONE OF UPR CONFLUENCE BTWN THE BASE OF UPR TROF CENTERED
NEAR HUDSON BAY AND UPR RDG IN THE SE CONUS...THE SHRTWV/SFC LO ARE
EXPECTED TO WEAKEN...ESPECIALLY THIS AFTN. EVEN SO...TIGHT PRES
GRADIENT/SHARP NLY FLOW ON THE WRN FLANK OF THE DEPARTING LO ARE
FCST TO ADVECT MUCH COLDER AIR LURKING TO THE N INTO THE UPR LKS.
EXPECT INCRSG POPS OVER THE W BY SUNRISE TO SPREAD EWD WITH THE
DEEPER MSTR UNDER THE CCB. FCST SDNGS STILL SHOW SOME SHARP COOLING
BLO ELEVATED WARM LYR...SO WL RETAIN MENTION OF SLEET IN THE
TRANSITION BTWN ALL RA AND MORE SN ONCE DEEPER COLD AIR ARRIVES OVER
THE W BY AFTN. BUT STRONG CAD/WEAKENING UPR DVGC AS JET CORE SHIFTS
TO THE NE WL TEND TO CAUSE THE CCB TO DECAY A BIT AS LARGER SCALE
QVECTOR DVGC DVLPS OVER THE CCB. ALTHOUGH FCST H85 TEMPS FALLING AS
LO AS -13C TO -15C BY 00Z COULD ADD SOME LK ENHANCED COMPONENT INTO
THE PCPN FIELD...WEAKENING DYNAMICS SHOULD LIMIT THIS POTENTIAL WITH
THE COLDEST AIR ARRIVING ONLY AFT 18Z ONCE LARGER SCALE QVECTOR DVGC
DOMINATED BY THE CAD IS IN PLACE. SO EXPECT SN ACCUMS TO BE SUB
ADVY. THE ARRIVAL OF THE COLDER AIR WL SHARPEN LLVL INSTABILITY AND
AID MIXING OF H925 WINDS UP TO 35 TO 45 KTS. ALTHOUGH THE APRCH FM
THE WSW OF THE SHARP PRES RISE CENTER WL RESULT IN ISALLOBARIC WIND
COMPONENT AT A RIGHT ANGLE OR EVEN OPPOSING THE GRADIENT FLOW AND
THE LO WL BE WEAKENING WITH TIME... THE MAGNITUDE OF THE GRADIENT
WIND IN CONCERT WITH FAVORABLE MIXING UNDER THE INCOMING THERMAL
TROF JUSTIFY ISSUANCE OF HI WIND ADVYS FOR EXPOSED LOCATIONS NEAR
THE LK SUP SHORE.
TNGT...AS HI PRES BLDS INTO THE WRN CWA OVERNGT...THE PRES GRADIENT
WL DIMINISH QUICKLY FOLLOWING PASSAGE OF PRES RISE CENTER TO THE E
AFT 00Z. SO EXPECT GUSTY WINDS TO DIMINISH QUICKLY THIS EVNG INTO
THE OVERNGT. BUMPED POPS UP TO LIKELY IN AREAS E OF MQT WITH H85
THERMAL TROF/TEMPS AS LO AS -13C TO -15C CONDUCIVE FOR SOME LES IN
MOIST CYC NW FLOW. SUBSIDENCE DROPPING INVRN AOB 3K FT/RISING H85
TEMPS/WEAKENING CYC FLOW OVERNGT WL CAUSE ANY SHSN TO DIMINISH
STEADILY AFT MIDNGT. CONSIDERING THE CHILL OF THE INCOMING
AIRMASS...PWAT FALLING BLO 0.25 INCH...AND THE PROSPECT OF CLRG OVER
THE INTERIOR W AS HI PRES BLDS OVHD...TENDED TO GO LOWER THAN
PREVIOUS FCST FOR MIN TEMPS IN THAT AREA.
TUE...HUDSON BAY HI PRES/DRY AIRMASS WL DOMINATE UPR MI...BRINGING
RELATIVELY DRY AND TRANQUIL WX. ALTHOUGH THERE WL BE SOME LINGERING
SC OVER MAINLY THE E HALF IN THE MRNG WITH LINGERING LIGHTER CYC
FLOW/LLVL MSTR/THERMAL TROF UNDER SUBSIDENCE INVRN...THIS CLD SHOULD
DISSOLVE BY AFTN WITH ARRIVAL OF SFC HI PRES RDG/ACYC FLOW AND
DAYTIME HEATING...GIVING WAY TO JUST SOME DIURNAL CU. MIXING TO H85
ON GFS FCST SDNGS WOULD YIELD HI TEMPS RANGING FM ARND 40 AT ERY TO
50 NEAR THE WI BORDER...BUT THE DAY WL BE COOLER NEAR THE MODIFYING
INFLUENCE OF THE LKS AS WEAK PRES GRADIENT IN THE AFTN WL ALLOW FOR
LK BREEZE DEVELOPMENT.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 556 AM EDT MON APR 16 2012
MUCH OF LONGER RANGE PORTION OF FCST IS DOMINATED BY NEGATIVE UPPER
AIR ANAMOLIES STATIONED OVER NORTHEAST PACIFIC OCEAN/GULF OF ALASKA
AND OVR HUDSON BAY INTO NUNAVUT CANADA. ZONAL FLOW FCST TO IMPACT
CONUS MUCH OF THE WEEK AND INTO NEXT WEEKEND AS WELL.
ATTM ONLY ONE SYSTEM IS SURE THING TO IMPACT THE AREA IN THE LONGER
TERM. THIS IS STILL OPEN TO CHANGE DEPENDING ON TRACK OF LATE WEEK
SYSTEM.
SHORTWAVE ON SOUTHERN EDGE OF TROUGH OVR NORTHEAST PACIFIC/GULF OF
ALASKA FCST TO SLIDE ACROSS ROCKIES INTO NORTHERN PLAINS ON TUESDAY
NIGHT AND PUSH ACROSS UPPER GREAT LAKES ON WEDNESDAY. SW WINDS AHEAD
OF SFC-H85 TROUGH BRINGS MUCH WARMER/MOIST AIR INTO UPR LAKES IN WAKE
OF THE EARLY WEEK CHILL. JET STREAKS SLIDING ACROSS THE NORTHERN
PLAINS AND OVR ONTARIO SHOULD HELP SYSTEM STAY FAIRLY ORGANIZED AS
IT CROSSES CWA ON WEDNESDAY. APPEARS THAT SYSTEM WILL BE COMPACT AS
IT MOVES THROUGH...LEADING TO A FAIRLY STRONG WIND FIELD IN THE
VCNTY. HAVE INCREASED WINDS ESPECIALLY IN THE WAKE OF THE LOW LATE
WEDNESDAY INTO WEDNESDAY NIGHT NEAR LAKE SUPERIOR.
PTYPE MAY BE ISSUE INITIALLY WITH SNOW OR EVEN FREEZING RAIN
POSSIBLE INTERIOR CNTRL /10Z-12Z ON WEDNESDAY/ AS SWATH OF
PRECIPITATION ARRIVES OVER PERSISTENT SHALLOW COLD AIR. ANY WINTRY
PRECIP SHOULD BE BRIEF THOUGH AS STRONG WARM AIR ADVECTION SFC-H85
QUICKLY BECOMES DOMINANT. ADDED TSRA FOR WEDNESDAY AS WELL DUE TO
STEEP H7-H5 LAPSE RATES AOA 8C/KM. PRETTY DYNAMIC SYSTEM LOOKS TO
AFFECT THE AREA. GIVEN CONVECTIVE POTENTIAL MAY SEE RAIN TOTALS OVR
0.25 INCH IN SOME AREAS. STILL SOME POTENTIAL FOR SNOW AS SYSTEM
EXITS ON WEDNESDAY NIGHT. 850MB/925MB TEMPS AS LOW AS -10C/-6C STILL
LEAVES POTENTIAL FOR BRIEF LAKE ENHANCED SNOW OVR HIGHER TERRAIN OF
WEST CWA IF ENOUGH MOISTURE REMAINS IN PLACE. JUST LOW CHANCE POPS
FOR NOW.
IN THE EXTENDED...FRIDAY SYSTEM IS BACK ON FOR AT LEAST THE
SOUTHEAST QUARTER OF THE CWA...AT LEAST ACCORDING TO ECMWF AND
CANADIAN. ECMWF HAS SHOWN THIS OFF AND ON FOR LAST FEW DAYS AND
LATEST GFS HAS TRENDED NORTH...THOUGH IS STILL MAINLY SOUTH OF CWA
WITH ITS AXIS OF MAX QPF. SINCE SFC LOW IS STILL FCST TO PASS MAINLY
OVR CNTRL GREAT LAKES EVEN ON THE ECMWF...PCPN IF IT OCCURS WOULD
LIKELY STAY MAINLY IN FORM OF SNOW. ECMWF WOULD POINT TO SEVERAL
INCHES OF ACCUMULATION OVR SE CWA JUST NORTH OF H85-H7 LOW TRACK.
SYSTEM IS STILL NEAR THE ALLUTIANS IN THE PACIFIC SO EXPECT MORE
JUMPING AROUND ON THE POSITION OF THE LOW YET THIS WEEK. SOMETHING
TO DEFINITELY KEEP AN EYE ON THOUGH.
BEYOND FRIDAY APPEARS DRY WEATHER IS IN STORE FOR NEXT WEEKEND. WILL
NOT BE ESPECIALLY WARM THOUGH AS LARGER SCALE TROUGH RESIDES OVR
MUCH OF EASTERN CANADA AND EASTERN CONUS. SFC-H85 RIDGE WILL BE
OVERHEAD LEADING TO LIGHT WINDS/LK BREEZES. BEST CHANCE FOR DAYTIME
TEMPS AT LEAST NEAR NORMAL WILL BE WELL INLAND FM THE LAKES TOWARD
WISCONSIN BORDER. COULD ALSO BE CHILLY NIGHTS AS WELL...WITH TEMPS
POSSIBLY IN THE TEENS AND 20S. EXPECT RELATIVE HUMIDITIES TO BE ON
THE LOW SIDE FOR THE WEEKEND AS WELL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 126 AM EDT MON APR 16 2012
FORECAST OVER THE NEXT 24 HOURS IS FAIRLY COMPLEX WITH A LOW
PRESSURE SYSTEM AND WARM FRONT SHIFTING NORTHEASTWARD THROUGH MUCH
OF THE UPPER PENINSULA.
KIWD AND KCMX...CONDITIONS WILL REMAIN NEAR ALT LANDING MINS THROUGH
AT LEAST LATE MORNING AS FLOW BCMS ONSHORE AND NERLY. COLD ADVECTION
BEHIND FRONT WILL TURN SHRA TO SHSH BY LATE MORNING AS NORTH WINDS
GUSTS FM 30-35 KT. EXPECT CONDITIONS TO IMPROVE TO MVFR BY LATE MON
AFTERNOON AS RDG BUILDING IN WILL KNOCK DOWN WINDS AND BRING IN
DRIER AIR. STEEP LOW-LVL LAPSE RATES WILL KEEP MVFR CLOUDS INTACT
HOWEVER. INCLUDED TS VCNTY AT KIWD IN THE FIRST COUPLE OVERNIGHT
HRS.
KSAW...EXPECT CONDITIONS TO IMPROVE TO MVFR THROUGH THE EARLY
MORNING WITH WARMING AND MIXING AHEAD OF THE FRONTAL SYSTEM. WINDS
WILL SHIFT NW AND BCM GUSTY AOA 30 KT BEHIND COLD FRONT WITH SHRA
CHANGING TO SHSN ALTHOUGH EXPECT GENERALLY MVFR CONDITIONS. RDGG FM
THE WEST WILL DIE DOWN WINDS TOWARD MON EVENING AS LAKE ENHANCED
SNOW ENDS. MVFR CLOUDS WILL REMAIN THROUGH 06Z TUE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 556 AM EDT MON APR 16 2012
CONSIDERING A NUMBER OF OBS SHOWING WIND GUSTS UP TO 50 KTS OVER THE
W HALF WHERE TERRAIN ENHANCES THE PREVAILING NE FLOW EARLY THIS
MRNG...OPTED TO ISSUE STORM WARNINGS FOR THE 3 WESTERN ZONES OF LAKE
SUPERIOR. AS THE FLOW BACKS TO N...EXPECT THE WINDS TO SUBSIDE A BIT
WITH JUST N GALES THRU THE AFTN AS THE ARRIVAL OF MUCH COLDER
ENHANCES MIXING OF HIER MOMENTUM TO THE LAKE SURFACE. EVEN THESE
WINDS WILL TEND TO DIMINISH OVER THE FAR W LATER IN THE DAY WITH
APPROACH OF HI PRES RIDGE. LINGERING GALES WILL END OVER THE REST OF
THE LAKE AS THE HI PRES RIDGE/WEAKER PRES GRADIENT DOMINATES THE
LAKE.
NEXT LOW PRES SYSTEM FCST TO MOVE THRU THE UPPER LAKES WED IS NOW
LOOKING STRONGER. EXPECT SOUTHERLY WINDS TO 30 KTS WEDNESDAY MORNING
TO SHIFT TO THE WEST AND INCREASE TO GALES ESPECIALLY OVER THE EAST
HALF OF THE LAKE BY LATER WEDNESDAY AFTN AND INTO THE EARLY EVENING.
WINDS DIMINISH BLO 25 KTS LATER WEDNESDAY NIGHT INTO THURSDAY AS
HIGH PRESSURE MOVES BACK OVR THE UPR LAKES REGION. SFC LOW PASSING
BY ACROSS THE CNTRL GREAT LAKES THURSDAY NIGHT INTO FRIDAY COULD
RESULT IN NORTHEAST WINDS 25-30 KTS OVR SOUTHERN PORTIONS OF LK
SUPERIOR.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND ADVISORY FROM 10 AM THIS MORNING TO 4 PM EDT THIS AFTERNOON
FOR MIZ002-003.
WIND ADVISORY FROM 10 AM THIS MORNING TO 8 PM EDT THIS EVENING
FOR MIZ001.
WIND ADVISORY FROM 5 PM THIS AFTERNOON TO 11 PM EDT THIS EVENING
FOR MIZ006-007.
WIND ADVISORY FROM 2 PM THIS AFTERNOON TO 8 PM EDT THIS EVENING
FOR MIZ005.
LAKE SUPERIOR...
GALE WARNING FROM 5 PM THIS AFTERNOON TO 2 AM EDT TUESDAY FOR
LSZ251-267.
GALE WARNING FROM 11 AM THIS MORNING TO 2 AM EDT TUESDAY FOR
LSZ266.
GALE WARNING FROM 11 AM THIS MORNING TO 8 PM EDT THIS EVENING
FOR LSZ265.
STORM WARNING UNTIL 2 PM EDT THIS AFTERNOON FOR LSZ263-264.
GALE WARNING FROM 2 PM THIS AFTERNOON TO 8 PM EDT THIS EVENING
FOR LSZ248-263-264.
GALE WARNING FROM 2 PM THIS AFTERNOON TO 2 AM EDT TUESDAY FOR
LSZ249-250.
GALE WARNING UNTIL 8 PM EDT THIS EVENING FOR LSZ242>245.
GALE WARNING UNTIL 2 PM EDT /1 PM CDT/ THIS AFTERNOON FOR LSZ240-
241.
STORM WARNING UNTIL 8 AM EDT /7 AM CDT/ THIS MORNING FOR LSZ162.
GALE WARNING UNTIL 2 PM EDT /1 PM CDT/ THIS AFTERNOON FOR LSZ162.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...KC
SHORT TERM...KC
LONG TERM...JLA
AVIATION...VOSS
MARINE...KC/JLA
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1040 AM EDT MON APR 16 2012
.SYNOPSIS...
STRONG SOUTHWEST WINDS TODAY WILL BRING SUMMERLIKE TEMPERATURES TO
THE REGION BEFORE A STRONG COLD FRONT SWEEPS ACROSS THE AREA DURING
THE AFTERNOON AND EVENING. THE FRONT WILL BRING THUNDERSTORMS
SOME OF WHICH MAY BECOME SEVERE. TEMPERATURES WILL THEN RETURN TO
NEAR AVERAGE FOR THE REST OF THE WEEK WITH THE NEXT CHANCE OF RAIN
ARRIVING ON THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE LATEST SURFACE MAP SHOWS LOW PRESSURE LOCATED OVER NORTH CENTRAL
WISCONSIN WITH THE COLD FRONT TRAILING SOUTH ACROSS LAKE MICHIGAN
AND WESTERN INDIANA. THE NARROW BAND OF SHOWERS AND ISOLATED
THUNDERSTORMS FORMING WELL AHEAD OF THE FRONT SHOULD EXPAND A BIT
MORE DURING THE AFTERNOON AS IT ENCOUNTERS DEEPER MOISTURE OVER THE
OHIO VALLEY AND LOWER GREAT LAKES. EXPECT THIS CONVECTION TO REACH
WESTERN NEW YORK A LITTLE AFTER 18Z...THEN SPREAD EAST ACROSS THE
REST OF THE CWA DURING THE REST OF THE AFTERNOON AND EVENING. THE
MAIN QUESTION IS HOW INTENSE WILL THE CONVECTION GET. CERTAINLY THE
UNIDIRECTIONAL SHEAR PROFILES ARE FAVORABLE FOR STRONG WIND GUSTS...BUT
THERE IS STILL SOME QUESTION ABOUT INSTABILITY...ESPECIALLY IN THE
WEST WHERE CLOUDS FROM THE UPSTREAM CONVECTION WILL BE ARRIVING
SOONER. THE LATEST RUC AND NAM12 STABILITY INDICES SHOW MORE
FAVORABLE CAPES (AVERAGING AROUND 1000-1500 J/KG) DEVELOPING
ACROSS THE GENESEE VALLEY AND FINGER LAKES AREA LATER THIS
AFTERNOON. THEREFORE...IT STILL LOOKS LIKE THE POTENTIAL FOR
DAMAGING THUNDERSTORM WIND GUSTS WILL BE GREATEST ACROSS THIS
AREA. KEEP IN MIND THOUGH...THAT CONVECTION THAT IMPACTS ANY PART
OF THE CWA WILL HAVE THE POTENTIAL TO TRANSPORT HIGHER WINDS ALOFT
DOWN TO THE SURFACE...AND CONVECTIVE CELLS WILL LIKELY BE MOVING
AT A PRETTY GOOD CLIP. WITH WARM TEMPS ALOFT...AND SOMEWHAT
QUESTIONABLY INSTABILITY... HAIL SHOULD BE A LESSER SECONDARY
RISK.
OTHERWISE...THE DEEP LAYERED SOUTHERLY FLOW AHEAD OF THE APPROACHING
FRONT WILL RESULT IN SUMMER-LIKE TEMPERATURES ACROSS THE AREA THIS
AFTERNOON. MANY AREAS WILL MAKE IT INTO THE LOW OR MID 80S WITH THE
WARMEST SPOTS LIKELY FROM THE GENESEE VALLEY INTO CENTRAL NY.
STRONG SYNOPTIC SCALE WINDS WILL ALSO BE A CONCERN LATER THIS
MORNING AND DURING THE AFTERNOON AS THE CORE OF A 50 TO 60 KNOT LOW
LEVEL JET TRACKS JUST TO OUR NORTHWEST. DAYTIME HEATING WILL PROMOTE
DEEP MIXING THROUGH THE BOUNDARY LAYER WITH STRONGER WINDS FROM
ALOFT MAKING IT DOWN TO THE SURFACE. BUFKIT MOMENTUM TRANSFER
SCHEMES SUGGEST GUSTS OF 40-45 KNOTS POSSIBLE FROM NEAR THE LAKE
ERIE SHORE NORTHEAST ACROSS THE NIAGARA FRONTIER TO NEAR ROCHESTER.
THEREFORE...A WIND ADVISORY REMAINS IN EFFECT FOR WESTERN NEW YORK
THROUGH 7PM.
TONIGHT...THE FRONT LOOKS TO STILL BE PUSHING ACROSS THE FAR EASTERN
FORECAST AREA WITH SHOWERS AND THUNDERSTORMS INTO THE EVENING. THE
FRONT WILL BE COMPLETELY EAST OF THE STATE BY MIDNIGHT. WINDS WILL
CONTINUE TO GUST BEHIND THE FRONT AS COLDER AND DRIER AIR FILTERS
IN. LOW TEMPERATURES WILL FALL INTO THE MID TO LOWER 40S WITH
CLEARING SKIES AND HIGH PRESSURE RIDGING IN FROM THE UPPER LAKES.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
SURFACE HIGH PRESSURE BEGINS TO BUILD INTO THE REGION AT THE
START OF THE PERIOD. SOME LEFTOVER LOW LEVEL MOISTURE COMBINED
WITH COLD AIR ADVECTION AND UPPER SHORT WAVE LIFTING ACROSS
THE REGION WILL RESULT IN A MODEST AMOUNT OF CLOUDINESS ON
TUESDAY...BUT SEE LITTLE IN THE WAY TO TRIGGER PRECIPITATION.
TUESDAY WILL BE A SHARPLY COOLER DAY THAN MONDAY WITH HIGHS SOME
20 TO 30 DEGREES COLDER THAN MONDAY`S HIGHS...MAINLY IN THE UPPER
40S TO LOWER 50S.
THE HIGH SETTLES OVER THE AREA TUESDAY NIGHT. CLEAR SKIES AND
LIGHT WINDS WILL BRING FROST/FREEZE CONCERNS AS OVERNIGHT LOWS
DROP INTO THE MID 20S TO LOWER 30S.
HIGH PRESSURE CONTINUES TO HOLD IN FIRM ACROSS THE AREA FOR
WEDNESDAY...PROVIDING A FAIR WEATHER DAY. AIR MASS LOOK
TO MODERATE WITH TEMPERATURES WARMING BACKING MID TO UPPER
50S...WITH A FEW LOWER 60S POSSIBLE.
CLOUDS WILL BE ON THE INCREASE EARLY WEDNESDAY NIGHT A RATHER
MODEST NORTHERN STREAM SHORTWAVE MOVES ALONG THE U.S./CANADIAN
BORDER...DRAGGING A COLD FRONT TOWARD WESTERN NEW YORK. AN
INCREASING LOW LEVEL JET AHEAD OFF THE FRONT SHOULD BE ABLE TO
PULL SUFFICIENT MOISTURE NORTHWARD AND INTERACT WITH THE
APPROACHING FRONT TO INCREASE THE PRECIPITATION THREAT OVERNIGHT
AND TOWARDS THURSDAY MORNING. THERE IS SOME MINOR FROZEN
PRECIPITATION POTENTIAL ACROSS PORTIONS OF THE SOUTHERN TIER AND
NORTH COUNTRY...BUT WARM AIR ADVECTION SHOULD ADVECT ABOVE
FREEZING DEWPOINTS INTO THESE AREAS BY THURSDAY MORNING...
THEREFORE IF ANY SNOW OR MIX OCCURS IT WILL BE VERY SHORT LIVED.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
A ZONAL FLOW WILL CONTINUE ACROSS NORTH AMERICA THIS TIME
PERIOD...THOUGH A LONGWAVE RIDGE WILL BUILD OVER THE WESTERN
US...WITH A CORRESPONDING TROUGH OVER THE CENTRAL PLAINS.
TEMPERATURES AROUND/FEW DEGREES ABOVE NORMAL TO START THE
PERIOD...AND COOLING DOWN WITH THE FALLING HEIGHTS ALOFT FOR THE
WEEKEND. A FRONTAL BOUNDARY LOOKS TO CROSS THE REGION ON THURSDAY
WITH RAIN SHOWERS...AND THEN INCREASING CHCS FOR PRECIPITATION LATER
OVER THE WEEKEND AS THE TROUGH NEARS THE REGION. FOR THE DETAILS...
ON THURSDAY BOTH THE 12Z GFS AND ECMWF CONTINUE TO PUSH A FRONTAL
BOUNDARY ACROSS THE REGION. CONSIDERING THE ZONAL FLOW AND MODEL
CONTINUITY CHANCES ARE INCREASING FOR RAIN SHOWERS ON THURSDAY. A
EMBEDDED SHORTWAVE WITHIN THE MEAN FLOW WILL CROSS THE REGION ALONG
WITH THE 12Z GFS BRINGING THE LEFT EXIT REGION OF A 90KNOT 250 HPA
JET ACROSS THE REGION...WITH BOTH FEATURES ADDING TO THE LARGE SCALE
LIFT...AND WE WILL INCREASE POPS TO MID/HIGH CHCS THURSDAY THOUGH
QPF LOOKS TO REMAIN LIGHT.
WITH THE FRONTAL BOUNDARY PUSHING TO THE SOUTH AND EAST OF THE
REGION THURSDAY NIGHT WILL CONTINUE WITH SLIGHT CHC POPS WITH CLOUDY
SKIES SLOWLY CLEARING OVERNIGHT.
FRIDAY AND SATURDAY BOTH THE ECMWF AND GFS DEVELOP A STORM SYSTEM
ACROSS THE SOUTHERN PLAINS UNDER THE LARGE SCALE TROUGH OVER THE
PLAINS. BOTH MODEL SOLUTIONS...ALONG WITH THE MAJORITY OF THE 00Z
GEFS TAKE THIS SYNOPTIC LOW JUST TO OUR SOUTH AND EAST LEAVING THE
EASTERN GREAT LAKES ON THE COOL SIDE WITH RAIN SHOWERS. WILL
INCREASE POPS THROUGH THE DAY FRIDAY...THOUGH AT THIS TIME THE BEST
CHCS MIGHT BE LATER FRIDAY AND THROUGH SATURDAY.
AS THIS SYSTEM PULLS TO THE EAST LATER IN THE WEEKEND BOTH THE ECMWF
AND GFS DROP 850 HPA TEMPERATURES ACROSS THE REGION TO BELOW ZERO.
THE GFS IS MUCH COOLER ALOFT...DUE IN PART TO THE DEEPER LOW ACROSS
NEW ENGLAND PULLING THE COLD AIR SOUTHWARD. STILL GIVEN THE TRACK/
AND SUPPORT FROM THE GEFS PRECIPITATION CANNOT RULE OUT SOME LIGHT
SNOW SATURDAY NIGHT OR SUNDAY ESPECIALLY OVER HIGHER TERRAIN. FOR
NOW WILL GO JUST SLIGHT CHC FOR SNOW IN THE GRIDS AS THE TRACK AND
DEPTH OF THE SYNOPTIC LOW THIS FAR OUT CAN CHANGE QUITE A BIT. WITH
BOTH 12Z RUNS OF THE GFS AND ECMWF DISPLAYING AN UPPER LEVEL TROUGH
OVER THE REGION WILL UNDERCUT HIGHS BY SEVERAL DEGREES FROM MODEL
GUIDANCE AND HAVE HIGHS IN THE 40S ACROSS THE REGION.
&&
.AVIATION /15Z MONDAY THROUGH FRIDAY/...
VFR CONDITIONS ACROSS THE AREA THIS MORNING POSSIBLY LOWERING TO
MVFR THIS AFTERNOON IN THUNDERSTORMS. STRONG WINDS WILL PICKUP THIS
MORNING AS A 50 KT LOW LEVEL JET SETS UP OVER THE AREA BRINGING
SURFACE WIND GUSTS OF 30-45 KNOTS. THE STRONGEST WINDS EXPECTED
ACROSS WESTERN NY FROM LAKE ERIE NORTHEAST ACROSS KBUF-KIAG-KROC. A
COLD FRONT WILL SLIDE ACROSS THE STATE DURING THE LATE AFTERNOON
WITH A LINE OF FAST MOVING THUNDERSTORMS. THESE STORMS HAVE THE
POTENTIAL TO TAP INTO THE STRONGER WINDS ALOFT AND PRODUCE SPORADIC
SURFACE WIND GUSTS TO 50 KTS. THE FRONT WILL MOVE EAST OF THE AREA
TONIGHT BUT WINDS WILL STAY GUSTY THROUGH THE EVENING AS COLDER AND
DRIER AIR FILTERS IN.
OUTLOOK...
MONDAY NIGHT...SHOWERS AND THUNDERSTORMS ENDING.
TUESDAY...VFR/MVFR CIGS.
WEDNESDAY...VFR.
THURSDAY AND FRIDAY...VFR/MVFR WITH A CHANCE OF SHOWERS.
&&
.MARINE...
SOUTH-SOUTHWEST WINDS WILL INCREASE TODAY WITH A MODERATE TO STRONG
PRESSURE GRADIENT DEVELOPING AHEAD OF A LOW MOVING INTO THE UPPER
GREAT LAKES. THIS WILL PRODUCE SMALL CRAFT ADVISORY CONDITIONS ON
LAKE ERIE AND THE WEST HALF OF LAKE ONTARIO. A STRONG COLD FRONT
WILL CROSS THE REGION THIS EVENING...WITH WINDS BECOMING WESTERLY
AND INCREASING LATER TONIGHT INTO TUESDAY WITH ANOTHER ROUND OF
SMALL CRAFT ADVISORY CONDITIONS ON BOTH LAKES ERIE AND ONTARIO.
WINDS WILL DIMINISH TUESDAY NIGHT AND WEDNESDAY AS HIGH PRESSURE
BUILDS INTO THE LOWER LAKES.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...WIND ADVISORY UNTIL 7 PM EDT THIS EVENING FOR NYZ001>003-
010>012-019-020-085.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR LEZ020.
SMALL CRAFT ADVISORY UNTIL 4 PM EDT TUESDAY FOR LEZ040-041.
SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR
LOZ030-042-043.
SMALL CRAFT ADVISORY UNTIL 10 PM EDT THIS EVENING FOR
SLZ022-024.
&&
$$
SYNOPSIS...SMITH
NEAR TERM...SMITH/TJP
SHORT TERM...TMA
LONG TERM...THOMAS
AVIATION...SMITH
MARINE...SMITH/TMA
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1020 AM EDT MON APR 16 2012
.SYNOPSIS...
A COLD FRONT WILL APPROACH THE MOUNTAINS FROM THE WEST TODAY...THEN
PROGRESS INTO CENTRAL NORTH CAROLINA TONIGHT. THE FRONT IS EXPECTED
TO STALL OUT IN VICINITY OF THE SOUTHEAST COAST THROUGH MID WEEK.
&&
.NEAR TERM /TODAY/...
AS OF 1020 AM MONDAY...
THE LATEST SURFACE ANALYSIS SHOWED HIGH PRESSURE JUST OFFSHORE
NOSING WEST THROUGH CENTRAL NORTH CAROLINA...WITH MSAS INDICATIVE OF
SURFACE-BASED DIVERGENCE OVER THE AREA. ON UPPER-AIR ANALYSES...
850MB MOISTURE WAS BEGINNING TO MOVE THROUGH THE WESTERN THIRD OF
THE STATE...WITH 850MB DEW POINTS JUST BELOW 10C. HOWEVER...THE MID-
AND UPPER-LEVEL RIDGE AXES WERE FIRMLY IN PLACE OVER THE FAR EASTERN
PART OF THE STATE AND ALONG THE COAST...WITH CONSIDERABLE DRY AIR
NOTED AT 700MB AND VERY DRY AIR ALSO NOTED IN THE MID-LEVELS ON
WATER VAPOR IMAGERY. THE LATEST NAM BUFR SOUNDINGS REMAINED STABLE
DURING THE DAY...AS THE CAP AT AND JUST ABOVE 700MB HOLDS EVEN AS
850MB THETA-E VALUES INCREASE OVER THE WESTERN PIEDMONT AND
PRECIPITABLE WATER VALUES RISE TO NEARLY 1.25 INCHES. THE RUC IS NOT
AS UNSTABLE AS THE NAM THIS AFTERNOON...LIFTED INDICES OF 0C TO -1C
ON THE FORMER VERSUS -2C TO -3C ON THE LATTER...AND EVEN THE NAM IS
PREDOMINANTLY SUBSIDENT DURING THE AFTERNOON. WILL CONTINUE TO KEEP
THE FORECAST DRY.
MORNING KGSO AND AMDAR SOUNDINGS SHOWED WINDS ONCE AGAIN JUST OFF
THE SURFACE A LITTLE HIGHER THAN WAS FORECAST BY SUNDAY GUIDANCE...
CLOSE TO 40KT. AS MIXING OCCURS THESE WINDS SHOULD DIMINISH...AND
MIXING SHOULD NOT TAKE PLACE FAST ENOUGH TO RESULT IN GUSTS BEYOND
THE 20S KTS. BUFR SOUNDINGS SHOW GUST POTENTIAL IS HIGHEST TOWARD
KGSO...WHERE SOME GUSTS APPROACHING 25KT ARE POSSIBLE. 1000-850MB
THICKNESSES SUPPORT HIGHS AS CURRENTLY FORECAST...SOLIDLY 81 TO 86
WITH MAYBE A LOCATION OR TWO APPROACHING THE UPPER 80S. SURFACE DEW
POINTS WILL BE SIMILAR TO SUNDAY...AND WITH THE WARMER TEMPERATURES
RELATIVE HUMIDITIES WILL BE A LITTLE LOWER...BOTTOMING OUT AT OR
JUST BELOW 35 PERCENT. WITH THE DRY FUELS IN PLACE...AN INCREASED
FIRE DANGER CONTINUES TO BE NOTED FOR THE AFTERNOON...INTO EARLY
EVENING.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY/...
AS OF 345 AM MONDAY...
OVERVIEW:
SHORTWAVE ENERGY DIGGING SOUTHEAST THROUGH THE 4-CORNERS REGION AT
06Z THIS MORNING WILL ROUND THE BASE OF THE LONGWAVE TROUGH PRESENT
OVER THE CENTRAL CONUS TODAY...THEN PROGRESS EASTWARD INTO THE DEEP
SOUTH DURING THE DAY TUESDAY AS A MORE ZONAL PATTERN DEVELOPS OVER
THE LOWER 48 IN THE WAKE OF THE DEAMPLIFYING UPPER LEVEL LOW
PROGRESSING TOWARD THE CANADIAN MARITIMES. THE FRONT WILL BECOME
INCREASINGLY W-E ORIENTED OVER THE AREA TONIGHT AS THE PARENT LOW
WEAKENS AND TRACKS WELL NORTHEAST INTO CANADA. THE FRONT IS EXPECTED
TO STALL OUT NEAR THE SANDHILLS/COASTAL PLAIN PORTION OF THE NC/SC
BORDER DURING THE DAY TUE.
TONIGHT:
MID-LEVEL LAPSE RATES WILL WEAKEN FROM WEST-EAST OVERNIGHT AS THE
UPPER LEVEL RIDGE SHIFTS OFFSHORE...HOWEVER...INCREASING BOUNDARY
LAYER MOISTURE IN ASSOC/W THE FRONTAL ZONE PROGRESSING INTO THE AREA
MAY ALLOW FOR A VERY MARGINAL AMOUNT OF MUCAPE...ON THE ORDER OF 250
J/KG. W/REGARD TO FORCING...VERY WEAK/SHALLOW LOW LEVEL CONVERGENCE
WILL BE PRESENT OVER THE AREA AS THE FRONT SLOWS DOWN AND BECOMES
INCREASINGLY W-E ORIENTED OVER THE AREA. ALTHOUGH A WEAK DISTURBANCE
IN SOUTHWEST FLOW ALOFT CANNOT BE RULED OUT...THE AFOREMENTIONED
SHORTWAVE IS EXPECTED TO PROGRESS NO FURTHER THAN EASTERN TX BY 12Z
TUE...AND THE BEST CHANCE FOR SMALL AMPLITUDE DISTURBANCES OR
CONVECTIVE RELATED FEATURES IS EXPECTED TO BE UPSTREAM IN THE DEEP
SOUTH. IF AN UPPER LEVEL DISTURBANCE PROGRESSES INTO THE AREA VIA SW
FLOW ALOFT IN THE PRESENCE OF MARGINAL MUCAPE AND WEAK/SHALLOW
LOW-LEVEL CONVERGENCE A FEW ISOLD SHOWERS COULD NOT BE RULED OUT IN
THE WEST/SW PIEDMONT...THOUGH THAT SCENARIO APPEARS UNLIKELY. WITH
THE ABOVE IN MIND...WILL KEEP THE FCST DRY. GIVEN INCREASING
BOUNDARY LAYER MOISTURE AND LOW/MID LEVEL CLOUD COVER...EXPECT LOWS
IN THE LOWER/MID 60S.
TUESDAY:
COMPLEX FORECAST. THE AFOREMENTIONED SHORTWAVE WILL PROGRESS EAST
INTO THE DEEP SOUTH (MS/AL) BY TUE AFT/EVE...WITH BROAD H5 HEIGHT
FALLS (40 METERS 12-00Z) DOWNSTREAM OVER THE CAROLINAS ALONG WITH AN
INCREASING POTENTIAL FOR SMALL AMPLITUDE DISTURBANCES OR CONVECTIVE
RELATED FEATURES PROGRESSING INTO THE AREA VIA SW FLOW ALOFT.
HOWEVER...THE BEST UPPER LEVEL FORCING ASSOC/W THE SHORTWAVE WILL
REMAIN WELL UPSTREAM OF THE AREA (MS/AL)...AND THE TIMING/LOCATION
OF ANY SMALLER AMPLITUDE DISTURBANCES ARE VERY MUCH IN QUESTION AT
THIS TIME...AND MAY ULTIMATELY DEPEND ON THE EVOLUTION OF DEEP
CONVECTION OVER THE LOWER MS RIVER VALLEY LATE TONIGHT AND TUE
MORNING. COMPLICATING MATTERS FURTHER...MODEL GUIDANCE VARIES ON THE
POSITION OF THE STALLED FRONTAL ZONE ON TUE...RANGING FROM DIRECTLY
OVER CENTRAL NC (00Z ECMWF)...TO JUST S/SE OF THE AREA (00Z GFS)...
TO PORTIONS OF THE SANDHILLS/SE COASTAL PLAIN (00Z NAM). THE
LOCATION OF THE SFC FRONT WILL LARGELY DETERMINE THE LOCATION/EXTENT
OF DIURNAL DESTABILIZATION TUE AFTERNOON. REGARDLESS...THE RELATIVE
BEST INSTABILITY IS EXPECTED TO BE PRESENT IN FAR S/SE PORTIONS OF
THE AREA WHERE 500-1000 J/KG OF MLCAPE IS PROGGED. GIVEN
CONSIDERABLE UNCERTAINTY WITH THE TIMING/LOCATION OF UPPER LEVEL
FORCING AND THE SURFACE FRONT AS MENTIONED ABOVE...WILL LEAVE THE
PREVIOUS FCST MORE OR LESS INTACT...INDICATING CHANCES FOR
SHOWERS/STORMS RANGING FROM 20-50%...LOWEST IN THE NE COASTAL PLAIN
AND HIGHEST NEAR THE SC BORDER/SE COASTAL PLAIN. HIGH TEMPS ARE
EQUALLY CHALLENGING ON TUE...WITH A BUST POTENTIAL OF 3-7F DEPENDING
ON THE LOCATION OF FRONT AND TIMING/LOCATION OF ANY CONVECTION THAT
MAY BE PRESENT. A BLEND OF MODEL GUIDANCE APPEARS REASONABLE...WITH
HIGHS RANGING FROM THE LOWER 80S SOUTH/SE TO MID 70S N/NW.
SEVERE THREAT:
SPC HAS HIGHLIGHTED A SLIGHT RISK FOR SEVERE STORMS OVER GA/SC AND
FAR SOUTHERN PORTIONS OF CENTRAL NC...PRIMARILY ADJACENT TO THE SC
BORDER. CONSIDERABLE UNCERTAINTY PERSISTS WITH REGARD TO THE
LOCATION/COVERAGE OF CONVECTION TUE AFTERNOON AS MENTIONED ABOVE...
THOUGH THE MOST LIKELY LOCATION IS IN THE FAR SW PIEDMONT...
SANDHILLS AND SE COASTAL PLAIN WHERE 500-1000 J/KG MLCAPE IS
PROGGED. THE HEIGHT GRADIENT ALOFT WILL TIGHTEN OVER THE CAROLINAS
ON TUE AS THE SHORTWAVE PROGRESSES INTO THE DEEP SOUTH...AND 0-6 KM
BULK SHEAR VALUES ARE PROGGED TO BE AT LEAST IN THE 30-35 KT RANGE
IN SOUTHERN PORTIONS OF THE AREA (HIGHER NORTH)...WITH LARGER
AMOUNTS (40-45 KT) POSSIBLE. AS A RESULT...DEEP LAYER SHEAR WILL
CERTAINLY BE SUFFICIENT FOR MULTICELLULAR ORGANIZATION...AND
POSSIBLY SUPERCELLULAR. GIVEN VERY WEAK LOW-LEVEL SHEAR...EVEN IN
VICINITY OF THE STALLED FRONT...THE PRIMARY SEVERE THREAT WILL
LIKELY BE CONFINED TO HAIL/WIND. AN ISOLD BRIEF/WEAK TORNADO COULD
NOT BE ENTIRELY RULED OUT...THOUGH ONLY IN ASSOCIATION WITH
STORM-SCALE INTERACTIONS. -VINCENT
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
AS OF 325 AM MONDAY...
COOLER AND DAMP PERIOD MID WEEK... POTENTIAL FOR HEAVY RAIN NEXT
WEEKEND...
MODELS CONTINUE TO POINT TOWARD A COOL DAMP PERIOD TUESDAY NIGHT
THROUGH WEDNESDAY NIGHT... FOLLOWED BY A GRADUAL DRYING AND WARMING
THURSDAY AND FRIDAY. IT APPEARS THAT A FINAL MID-UPPER LEVEL WAVE
WILL BE DAMPENING OUT AS IT MOVES EAST ACROSS OUR REGION WEDNESDAY
AFTERNOON AND EVENING. THIS WEAKENING TREND IS SUPPORTED BY THE
MODELS GIVEN THE EXPECTED INCREASING ZONAL FLOW ALOFT DURING THE
PERIOD. AT THE SURFACE... A COOL HIGH PRESSURE IS EXPECTED TO BECOME
FULLY ESTABLISHED FROM NEW ENGLAND SOUTHWARD INTO SC BY 12Z/WED.
THIS HIGH IS OF SUFFICIENT STRENGTH (1025+ MB) AND FAVORABLE
POSITION (NY AND PA) FOR THE DEVELOPMENT OF A SPRING TIME CAD EVENT
OVER OUR REGION. THE TEMPERATURES WEDNESDAY MAY STAY IN THE 50S FOR
MUCH OF THE PIEDMONT ESPECIALLY IF THE QPF OF 0.25 TO 0.50 FORECAST
BY MOST MODELS IS REALIZED.
THE MID LEVEL WAVE IS EXPECTED TO REMAIN STRONG ENOUGH TO HELP
GENERATE ENOUGH LIFT FOR LIGHT TO MODERATE STRATIFORM RAINS OVER OUR
REGION WEDNESDAY. THE BEST CHANCE OF RAIN APPEARS THAT IT WILL BEGIN
IN THE SW-W PIEDMONT EARLY IN THE DAY... THEN SPREAD EAST ACROSS
CENTRAL AND EASTERN AREAS DURING THE DAY. HIGHS WILL LIKELY BE ONLY
IN THE UPPER 50S NW TO UPPER 60S SE. IT APPEARS THAT THUNDER WOULD
BE HARD TO COME BY GIVEN THE DAMPENING WAVE ALOFT AND THE
STRENGTHENING CAD CONDITIONS/STABILITY NEAR THE SURFACE. WE WILL
CARRY LIKELY POP FOR RAIN IN THE WEST DURING THE MORNING... AND
CHANCES EAST... SPREADING THE LIKELY POP EAST TO COVER ALL ZONES BY
AFTERNOON AND EVENING. ONCE THE WAVE PASSES... THE RAIN IS EXPECTED
TO TAPER OFF BY 12Z/THU. WE WILL KEEP SOME LOW POP IN THE COASTAL
PLAIN THROUGH 15Z OR SO THU... FOLLOWED BY GRADUAL CLEARING DURING
THE DAY. THE CONTINUED NE FLOW WILL LIKELY MEAN A SLOW CLEARING
PATTERN. SKIES SHOULD BECOME PARTLY CLOUDY THU AFTERNOON AND
CONTINUE INTO FRIDAY AS WEAK HIGH PRESSURE WILL LINGER OVER NC...
BEFORE SHIFTING OFFSHORE FRIDAY. HIGHS THURSDAY AND FRIDAY WILL
RECOVER BACK INTO THE 70S RATHER SLOWLY.
FOR FRIDAY NIGHT THROUGH THE WEEKEND...
THE CONTINUES TO BE A LARGE SPREAD OF SOLUTIONS FOR AN EXPECTED EAST
COAST TROUGH/LOW PRESSURE DEVELOPMENT. THE LATEST GFS AND EC
INDICATE A COASTAL STORM BY LATE SAT-SUN WITH A CHILLY RAIN FOR
CENTRAL NC. PLAN NOW IS TO KEEP CURRENT FORECAST CONTINUITY... WITH
BEST CHANCE OF RAIN OVER THE WEEKEND. THE EC SOLUTION IS ON THE SW
SIDE OF THE ENVELOP OF SOLUTIONS (STRONG SURFACE LOW DEVELOPS OVER
NW GULF OF MEX SATURDAY... THEN DEEPENS (990 MB) AS IT RIDES NE OVER
NC SUNDAY. THIS SOLUTION IS ALSO ON THE EXTREME DEEP SIDE OF THE
OTHER GUIDANCE. HOWEVER... MOST SOLUTIONS INDICATE A POTENTIAL FOR
HEAVY RAIN... A PERIOD OF STRONG STORMS WITH THE ACTUAL COLD
FRONT... AND EVEN A TURN TO A CHILLY RAIN LATE IN THE WEEKEND. WE
WILL TREND THE FORECAST TOWARD A WETTER SOLUTION SAT-SUN.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
AS OF 730 AM MONDAY...
24-HR TAF PERIOD:
A STRONG MID-LEVEL SUBSIDENCE INVERSION ASSOC/W THE UPPER LEVEL
RIDGE CURRENTLY IN PLACE (THOUGH BEGINNING TO SHIFT OFFSHORE THIS
AFTERNOON THROUGH TONIGHT) WILL REMAIN IN PLACE OVER CENTRAL NC
THROUGH THE REMAINDER OF THE TAF PERIOD...AND EXPECT VFR CONDITIONS
TO PREVAIL WITH SCATTERED DIURNAL CU (6 KFT AGL) DURING PEAK
HEATING. A 5-10 KT SOUTHWESTERLY BREEZE WILL INCREASE TO 10-15 KT
SUSTAINED WITH GUSTS UP TO 20-25 KT BY 15Z IN ASSOC/W A TIGHTENING
MSLP GRADIENT AND STRONG DIURNAL HEATING/MIXING. WINDS WILL BECOME
WEST SOUTHWEST AND WEAKEN TO 5-10 KT AT SUNSET...THEN VEERING TO THE
NORTH/NE AT 10 KT BETWEEN 06-12Z TUE MORNING IN ASSOC/W A COLD FRONT
PROGRESSING THROUGH THE AREA FROM NORTH-SOUTH.
LOOKING AHEAD:
THE NEXT CHANCE FOR SUB-VFR CONDITIONS IS EXPECTED TO BE ASSOC/W SCT
SHOWERS AND STORMS DURING THE DAY TUESDAY AS THE AFOREMENTIONED
FRONT STALLS OVER THE CAROLINAS. THE LATEST MODEL GUIDANCE SUGGESTS
A COASTAL LOW/CAD WEDGE SETUP OVER THE CAROLINAS MID-WEEK...AND THE
POTENTIAL EXISTS FOR AN EXTENDED PERIOD OF MVFR/IFR CONDITIONS LATE
TUE NIGHT INTO THE DAY THU...THOUGH CONFIDENCE REMAINS RELATIVELY
LOW. -VINCENT
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...DJF
SHORT TERM...VINCENT
LONG TERM...BADGETT
AVIATION...VINCENT
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1014 AM EDT MON APR 16 2012
.SYNOPSIS...
A COLD FRONT CROSSES THIS EVENING. A WAVE DEVELOPS ALONG THE FRONT
AND SKIRTS THE MOUNTAINS TUESDAY NIGHT THROUGH WEDNESDAY EVENING.
WARMER AFTERNOON TEMPERATURES RETURN FOR THE END OF THE WORK WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
10 AM UPDATE. MAIN CHANGE WAS TO INCREASE WIND GUSTS TO 30 TO 40 MPH
THIS AFTERNOON...GIVEN STRONGER WINDS OFF THE SURFACE AND MIXING.
HOWEVER...RELATIVE HUMIDITIES WILL REMAIN HIGH ENOUGH TO PRECLUDE A
FIRE DANGER STATEMENT. CURRENT BAND OF SHOWERS DISSIPATING TO OUR
WEST AS INDICATED BY MODELS. AM CONCERNED ABOUT PROSPECTS OF
REDEVELOPMENT OF STORMS THIS AFTERNOON AHEAD OF FRONT AS SOUNDING
PROFILES LACK DEEPER MOISTURE. BUT WILL KEEP POPS AS IS THIS
AFTERNOON...GIVEN DYNAMICS ARE THERE FOR THAT THIN LINE AHEAD OF THE
FRONT AND SPC STILL HAS US IN A SLIGHT RISK OF SEVERE.
PREVIOUS DISCUSSION BELOW...
TIMING OF FRONT AND PREFRONTAL ACTION LOOKS GOOD FROM PREV FCST.
CONCERNED ABOUT POTENTIAL LACK OF REDEVELOPMENT OF PREFRONTAL BAND
THIS AFTN. MDLS ARE NOT THRILLED WITH BAND LIGHTING BACK UP AS IT
ENTERS WESTERN ZONES BY 18Z. RAPID RUC ALSO LACKLUSTER WITH ITS
MODELED REFLECTIVITY FOR TOMORROW. GIVEN THIS AND STOUT RIDGE
CURRENTLY OVER THE AREA AMID A DRY BL AND THE FACT THIS WILL BE
RACING OUT WELL AHEAD OF ACTUALLY BAROCLINIC ZONE...ELECTED TO
KNOCK DOWN POPS SOME BUT NOT DOWN TO WHAT MDLS SUGGEST. THINKING
OF MORE ISO OR SCT CONCERNING COVERAGE WITH GREATEST COVERAGE
ALONG AND WEST OF OH RVR WITH SUBSEQUENT WEAKENING TOWARD MTNS.
MDL QPF LOOKS MEAGER TO SAY THE LEAST GIVEN LACK OF COVERAGE AND
PROGRESSIVE NATURE. WHAT CONVECTION THAT DOES FORM WILL HAVE TO BE
WATCHED FOR DAMAGING WIND GUSTS AS SPC CONT TO PAINT MUCH
OF CWA IN SLIGHT RISK. AS A RESULT WILL CONT WIND WORDING IN WX GRIDS.
ACTUAL FRONT WILL LAG SEVERAL HRS BEHIND...NOT GETTING INTO SE
OH UNTIL AFTER 00Z...WITH SUBSEQUENT OH RVR CROSSING BY 03Z AND
EXITING MTNS BY 09Z. ELECTED TO HAVE SOME SCHC POPS WITH ACTUAL
FROPA AS ENOUGH FORCING AND MOISTURE MAY EXIST FOR A FEW SHRA.
SHOULD BE WINDY TDY WITH AFTN MIXING AND GRADIENT TIGHTENING.
COULD SEE SOME 25 TO 30KTS GUSTS WITH LCL HIGHER IN ANY CONVECTION
AND WITH FROPA.
CLDS WILL STICK ARND TONIGHT WITH MID/HI LVL MOISTURE ADVECTING IN
FROM SW FLOW ALOFT.
FOR TMPS...LEANED TOWARD WARMER MAV EAST OF OH RVR AND COOLER MET
WEST OF THERE AS CONVECTION WOULD BE FIRING BEFORE MAX HEATING
COULD OCCUR THERE. WILL ALSO GO A HAIR ABV GUIDANCE E AND S FOR
TONIGHT AS BL SLOW TO COOL AND LINGERING CLDS.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
GFS/CANADIAN AND ECMWF ARE SHOWING A WAVE DEVELOPING AND SKIRTING
SOUTHERN AND EASTERN PORTIONS OF THE FORECAST AREA FOR TUESDAY NIGHT
THROUGH WEDNESDAY EVENING. NAM KEEPS THE WAVE SOUTH OF THE
REGION...BUT IS AN OUTLIER. THEREFORE WILL GO WITH A MAJORITY
SOLUTION AND PUSH POPS DEEPER INTO OUR TERRITORY AND INCREASE THEM
IN THE SOUTHEAST. THIS WILL ALSO NECESSITATE LOWERING HIGH
TEMPERATURES ON WEDNESDAY IN THE SOUTHERN AND EASTERN COUNTIES.
CANADIAN/GFS AND ECMWF ARE VERY SIMILAR WITH THE NEXT SYSTEM AS
WELL. THE MODELS WOULD KEEP AN APPROACHING FRONT NORTH OF THE
REGION. WILL KEEP JUST A SMALL POP IN THE NORTH THURSDAY
AFTERNOON...BUT THEN DRY GO THURSDAY NIGHT AS THE FRONT RETREATS
FURTHER NORTH. WITH AREA IN THE WARM SECTOR...WARMED HIGH
TEMPERATURES ON THURSDAY AND FRIDAY.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
QUITE A BIT OF UNCERTAINTY IN THE LONG TERM PERIOD AS MODELS HAVE
RUN TO RUN CONSISTENCY AND OVERALL AGREEMENT ISSUES. BUT GENERAL
CONSENSUS IS THAT A COLD FRONT IN ASSOCIATION WITH A LOW PRESSURE
SYSTEM MOVING EAST THROUGH CANADA WILL STALL OUT SOMEWHERE OVER THE
NORTHERN ZONES LATE THURSDAY/EARLY FRIDAY...WITH A LOW PRESSURE
SYSTEM OUT IN THE PLAINS MOVING NORTHEAST ALONG THE STALLED FRONTAL
BOUNDARY TOWARDS THE REGION FOR THE WEEKEND. THE LOW PRESSURE SYSTEM
AND ASSOCIATED COLD FRONT WILL PUSH EAST THROUGH THE REGION FRIDAY
THROUGH SATURDAY NIGHT...SPREADING SHOWERS AND THUNDERSTORMS INTO
THE REGION. THE LOW WILL MOVE OFF TO THE NORTHEAST ON SUNDAY...WITH
MUCH COOLER AIR FILTERING INTO THE REGION ON THE BACK SIDE OF THE
LOW. ANY LINGERING PRECIPITATION/MOISTURE IN THE NW UPSLOPE FLOW ON
THE BACK SIDE OF THE LOW COULD BE IN THE FORM OF A RAIN/SNOW MIX OR
EVEN SNOW OVER THE NORTHERN MOUNTAIN ZONES AS THE COLDER AIR TAKES
OVER ON THE BACK SIDE OF THE LOW.
&&
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
14Z MONDAY THRU 12Z TUESDAY...
PREDOMINATE VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD.
HOWEVER...BREEZY TO GUSTY SW WINDS 30 TO 40 KTS THIS AFTERNOON AS A
COLD FRONT APPROACHES FROM THE WEST LATE TDY.
A LINE OF SCATTERED TO BROKEN SHOWERS AND THUNDERSTORMS MAY MOVE
ACROSS THE AREA ROUGHLY BETWEEN 17Z-00Z...WEAKENING AS THEY CLOSE IN
ON MTNS. SOME OF THESE STORMS MAY BE STRONG TO SEVERE...WITH STRONG
WINDS. HAVE SOME TEMPO MVFR VSBY IN TSRA FOR MOST SITES EXCEPT IN
MTNS WHERE CONFIDENCE NOT HIGH ON CONVECTION MAINTAINING SIGNIFICANT
COVERAGE...THUS HELD WITH VCTS AND VFR WITH 12Z ISSUANCE.
AFTER 00Z...AS FRONT MOVES EAST OF AREA SHOWERS BASICALLY END WITH
VFR CONDITIONS PREVAILING.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z TUESDAY...
FORECAST CONFIDENCE...HIGH.
ALTERNATE SCENARIOS: WIND DIRECTION AND SPEED WILL TEND TO
FLUCTUATE. TIMING OF SHOWERS/THUNDERSTORMS MAY VARY.
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 H H H H H H H H H H H H
EKN CONSISTENCY H 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 H H H H H H H H H H H
AFTER 12Z TUESDAY...
IFR CONDITIONS POSSIBLE TUESDAY NIGHT THROUGH WEDNESDAY EVENING IN
SOUTHWEST VIRGINIA AND THE SOUTHERN WV MOUNTAINS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...RPY/JMV/30
NEAR TERM...JMV/30
SHORT TERM...RPY
LONG TERM...SL
AVIATION...JMV
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
951 AM EDT MON APR 16 2012
.SYNOPSIS...
A COLD FRONT OVER NW OHIO WILL MOVE EAST THROUGH THE AREA THIS AFTERNOON
THEN HIGH PRESSURE WILL CROSS THE REGION LATE TUESDAY INTO EARLY
WEDNESDAY. ANOTHER COLD FRONT WILL DROP INTO THE OHIO VALLEY EARLY
THURSDAY AND STALL. LOW PRESSURE WILL MOVE ALONG THE FRONT UP THE
OHIO VALLEY FRIDAY AND TO THE MID ATLANTIC COAST SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
COLD FRONT AT 13Z WAS ABOUT TO MOVE INTO NW OHIO. THERE WERE SOME
ISOLATED SHOWERS AHEAD OF THE BOUNDARY BUT THEY WERE DECREASING IN
COVERAGE AND INTENSITY AS THEY MOVED EASTWARD. CURRENT MODEL RUNS
CONTINUE TO BRING THE FRONT EASTWARD BUT THE AMOUNT OF CONVERGENCE
ALONG IT IS WEAK. STILL BELIEVE THERE WILL BE A NARROW LINE OF
CONVECTION THAT EVENTUALLY REDEVELOPS BUT IT MAY NOT OCCUR UNTIL
IT GETS INTO THE BETTER INSTABILITY THAT WILL OCCUR ACROSS THE
EASTERN HALF OF THE REGION. AT THIS POINT WE WILL GO WITH ISOLATED
TO SCATTERED CONVECTION IN THE ZONES. BEST CHANCES OF ANY SEVERE
THUNDERSTORM WIND GUSTS WILL BE ACROSS THE EASTERN COUNTY WARNING
AREA...LIKELY NEAR OR EAST OF A LINE FROM CANTON TO ASHTABULA.
GUSTY SOUTHWEST WINDS WILL BE AN ISSUE THROUGH THE DAY. INITIALLY
THE LOW LEVEL JET AHEAD OF THE FRONT WILL MIX TO THE SURFACE AND
SHOULD PRODUCE SOME GUSTS THAT ARE AROUND 45 KNOTS. THESE WINDS
WILL REMAIN STRONG IN THE WAKE OF THE FRONT FOR A FEW HOURS AS
THE STRONG PRESSURE RISES MOVE IN BEHIND THE LOW PRESSURE THAT IS
TRACKING THROUGH THE CENTRAL LAKES. SO EXPECT TO SEE GUSTS IN THE
WAKE OF THE FRONT CONTINUE IN THE 45 MPH RANGE. UNCERTAINTY AT
THIS POINT IS WHEN TO DECREASE THE WINDS. FOR NOW THE ADVISORY
TIME ENDING OF 10 PM LOOKS REASONABLE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
HIGH PRESSURE BUILDS IN FROM THE WEST TONIGHT SO STRONG WINDS WILL
DIMINISH FROM WEST TO EAST DURING THE EVENING BUT COULD STILL REMAIN
A LITTLE WINDY FOR THE SNOWBELT LAKESHORE INTO THE LATE NIGHT HOURS.
DRY PUNCH OF AIR BEHIND THE COLD FRONT SHIFTS INTO THE EAST DURING
THE EVENING. WRAP MOISTURE TRIES TO SPREAD EAST INTO THE CWA EARLY
TONIGHT BUT SUBSIDENCE WITH HIGH MOVING IN LOOKS TO BE TOO STRONG TO
ALLOW FOR ENOUGH CLOUDINESS TO PRODUCE ANY PRECIP.
HIGH PRESSURE WITH DRY CONDITIONS SHOULD OCCUR INTO WED NIGHT THEN
ANOTHER COLD FRONT WILL MOVE IN BRINGING A THREAT FOR SHRA MAINLY
FOR THE SECOND HALF OF WED NIGHT.
THE QUESTION FOR THU IS WHETHER THE FRONT WILL HAVE ENOUGH MOMENTUM
TO PUSH FAR ENOUGH S TO TAKE THE SHRA THREAT SOUTH OF THE CWA FOR
THU AFTERNOON AND EVENING. LOW PRESSURE WILL MOVE ALONG THE FRONT
AND SPREAD SHRA BACK NORTH OF THE FRONT THU NIGHT. RIGHT NOW MODELS
WANT TO KEEP GOOD DEEP MOISTURE OVER THE CWA LATE THU AND THU NIGHT
SO WILL SIDE WITH CAUTION AND KEEP THREAT FOR SHRA GOING ALL DAY THU
AS WELL AS THU NIGHT.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
ANOTHER COLD FRONT MOVES THROUGH ON FRIDAY WITH A FAIR AMOUNT OF
COLD AIR BEHIND IT. THE LAKE AND 850 MB TEMPERATURE DIFFERENCE WILL
BE NEAR 11 OR 12C. HIGH PRESSURE SLOWLY BUILDS IN FROM THE WEST. THE
GFS AND ECMWF ARE IN FAIR AGREEMENT FRIDAY AND SATURDAY. FOR SUNDAY
THE 00Z ECMWF HANGS UNTO THE PRECIPITATION LONGER IN THE FORECAST
AREA. AT THIS TIME REMAINED CONSISTENT WITH THE PREVIOUS FORECAST
BUT THIS WILL HAVE TO BE WATCHED. TEMPERATURES WILL BE BELOW NORMAL.
THE THREAT OF FROST IS POSSIBLE SATURDAY NIGHT BUT ESPECIALLY SUNDAY
NIGHT IF THE CLOUDS DECREASE AS EXPECTED.
&&
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
GUSTY WINDS AND A THREAT OF THUNDER ARE THE WEATHER PROBLEMS FOR
TODAY. THE SHOWERS OVER EASTERN INDIANA AND WESTERN OHIO ARE
DECREASING AS THEY MOVE EAST...THE HRRR MODEL CONCURS WITH THIS.
THE MODELS ARE TRYING TO FORECAST A NARROW SQUALL LINE DEVELOPING AHEAD
OF THE FRONT LATE THIS MORNING AND IT WILL MOVE EAST RAPIDLY. THINGS MAY
BE MOVING QUICKER AND THIS MAY LIMIT THE AMOUNT OF THUNDER AND
SEVERE WEATHER. THE BEST CHANCE FOR THUNDER IS FROM CLE EAST AS
THE AIRMASS WILL GET UNSTABLE ENOUGH. THE 00Z 4KM WRF-NMM HAS TWO
NARROW BANDS OF SHOWERS...ONE MOVES THROUGH BY EARLY AFTERNOON AND
THEN ANOTHER DEVELOPS LATE IN THE AFTERNOON. THE 4KM WRF IS THE
ONLY MODEL SHOWING THIS. ON THE EDGE ABOUT THIS.
THE PRESSURE GRADIENT INCREASED SO MOST PLACES ARE GUSTY...THUS
DECREASING THE THREAT OF SIGNIFICANT LOW LEVEL WIND SHEAR-LLWS.
THE HRRR MODEL INCREASES THE GUSTS AT THE SURFACE IN EXCESS OF 40
KNOTS BY NOON IN THE WARM ADVECTION. GETTING SOME SUNSHINE AT
TIMES WILL HELP. AT DAYBREAK SOME GUSTS TO 35 KNOTS WERE ALREADY
BEING REPORTED. THE WINDS WILL DECREASE AROUND SUNSET.
VFR FOR CLOUDS AND VISIBILITY EXCEPT IN SHOWERS AND THUNDERSTORMS.
HOWEVER...THE SREF IS TRYING TO INDICATE MVFR CEILINGS DEVELOPING
THIS MORNING AND ENDING THIS AFTERNOON. SOME MVFR CEILINGS HAVE
DEVELOPED IN INDIANA...BUT AS THE SHOWERS DECREASE...THE CLOUDS
MAY ALSO. WILL FORECAST SOME MVFR CEILINGS FOR TOL AND FDY.
.OUTLOOK...NON VFR POSSIBLE WEDNESDAY NIGHT INTO FRIDAY.
&&
.MARINE...
STRONG WARM ADVECTION WILL OCCUR THIS MORNING UNTIL THE COLD FRONT
BEGINS MOVING ACROSS LAKE ERIE FROM WEST TO EAST THIS AFTERNOON.
EVEN THOUGH PLENTY OF WARM AIR AND STRONG WINDS ALOFT...SUSTAINED
WINDS OF 20 TO 25 KNOTS WILL BE LIKELY LATER THIS MORNING AND THEN
BEHIND THE FRONT SUSTAINED WINDS OF 30 KNOTS WITH HIGHER GUSTS. SOME
CONCERN THAT ESPECIALLY ON THE EAST END THE WINDS COULD APPROACH
GALE FORCE. THE COLD ADVECTION IS NOT THAT SIGNIFICANT SO WILL
CONTINUE WITH THE 30 KNOTS SUSTAINED AND A SMALL CRAFT ADVISORY. THE
WINDS WILL DECREASE FROM WEST TO EAST TUESDAY AS HIGH PRESSURE
BUILDS IN. UNTIL THAT HAPPENS THE WATER LEVEL ON THE WEST END OF
LAKE ERIE COULD DROP LATE THIS AFTERNOON AND EVENING. AT THIS TIME
IT IS NOT EXPECTED TO DROP TO BELOW THE CRITICAL MARK FOR SAFE
NAVIGATION...THIS WILL BE WATCHED CLOSELY BY THE NEXT SHIFTS.
SOME MINOR THREAT THAT WAVES COULD APPROACH SMALL CRAFT ADVISORY ON
THURSDAY AFTER A COLD FRONTAL PASSAGE. AT THIS TIME 2 TO 4 FOOT
WAVES SEEM TO BE THE HIGHEST.
THE NEXT THREAT OF A SMALL CRAFT ADVISORY WILL BE FRIDAY NIGHT INTO
SUNDAY AS A LOW AND FRONT MOVES NEAR LAKE ERIE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...WIND ADVISORY UNTIL 10 PM EDT THIS EVENING FOR OHZ003-006>014-
017>023-027>033-036>038-047-089.
PA...WIND ADVISORY UNTIL 10 PM EDT THIS EVENING FOR PAZ001>003.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EDT TUESDAY FOR LEZ147>149.
SMALL CRAFT ADVISORY UNTIL 10 AM EDT TUESDAY FOR LEZ142>146.
&&
$$
SYNOPSIS...ADAMS
NEAR TERM...MULLEN
SHORT TERM...ADAMS
LONG TERM...KIELTYKA
AVIATION...KIELTYKA
MARINE...KIELTYKA
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
738 AM EDT MON APR 16 2012
.SYNOPSIS...
A COLD FRONT OVER INDIANA WILL MOVE EAST THROUGH THE AREA LATER
TODAY AND EARLY TONIGHT THEN HIGH PRESSURE WILL CROSS THE REGION
LATE TUESDAY INTO EARLY WEDNESDAY. ANOTHER COLD FRONT WILL DROP INTO
THE OHIO VALLEY EARLY THURSDAY AND STALL. LOW PRESSURE WILL MOVE
ALONG THE FRONT UP THE OHIO VALLEY FRIDAY AND TO THE MID ATLANTIC
COAST SATURDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
INITIAL BAND OF WEAKENING SHRA/ISOLD TSRA SHOULD MOVE INTO THE NW
CO`S OVER THE NEXT HOUR OR TWO THEN PROGRESS EAST INTO MAINLY THE
EASTERN CO`S FOR THE AFTERNOON. WITH DAYTIME HEATING COULD SEE SOME
OF THE STORMS BECOME SEVERE IN THE EAST WITH DAMAGING WINDS AND TO A
LESSER EXTENT POSSIBLE LARGE HAIL OR A BRIEF TORNADO. COVERAGE OF
CONVECTION IN QUESTION SO WILL STAY WITH JUST CHANCE POPS WHICH IS
STILL HIGHER THAN MAV GUIDANCE.
THE WINDS WILL ALSO BE AN ISSUE OUTSIDE OF THE TSRA AS 850 MB WINDS
AT FRONTAL PASSAGE TIME LOOK TO BE 50 TO 55 KNOTS. AFTER
COLLABORATION HAVE DECIDED TO GO WITH WIND ADVISORY VERSUS WIND
WARNING.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
HIGH PRESSURE BUILDS IN FROM THE WEST TONIGHT SO STRONG WINDS WILL
DIMINISH FROM WEST TO EAST DURING THE EVENING BUT COULD STILL REMAIN
A LITTLE WINDY FOR THE SNOWBELT LAKESHORE INTO THE LATE NIGHT HOURS.
DRY PUNCH OF AIR BEHIND THE COLD FRONT SHIFTS INTO THE EAST DURING
THE EVENING. WRAP MOISTURE TRIES TO SPREAD EAST INTO THE CWA EARLY
TONIGHT BUT SUBSIDENCE WITH HIGH MOVING IN LOOKS TO BE TOO STRONG TO
ALLOW FOR ENOUGH CLOUDINESS TO PRODUCE ANY PRECIP.
HIGH PRESSURE WITH DRY CONDITIONS SHOULD OCCUR INTO WED NIGHT THEN
ANOTHER COLD FRONT WILL MOVE IN BRINGING A THREAT FOR SHRA MAINLY
FOR THE SECOND HALF OF WED NIGHT.
THE QUESTION FOR THU IS WHETHER THE FRONT WILL HAVE ENOUGH MOMENTUM
TO PUSH FAR ENOUGH S TO TAKE THE SHRA THREAT SOUTH OF THE CWA FOR
THU AFTERNOON AND EVENING. LOW PRESSURE WILL MOVE ALONG THE FRONT
AND SPREAD SHRA BACK NORTH OF THE FRONT THU NIGHT. RIGHT NOW MODELS
WANT TO KEEP GOOD DEEP MOISTURE OVER THE CWA LATE THU AND THU NIGHT
SO WILL SIDE WITH CAUTION AND KEEP THREAT FOR SHRA GOING ALL DAY THU
AS WELL AS THU NIGHT.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
ANOTHER COLD FRONT MOVES THROUGH ON FRIDAY WITH A FAIR AMOUNT OF
COLD AIR BEHIND IT. THE LAKE AND 850 MB TEMPERATURE DIFFERENCE WILL
BE NEAR 11 OR 12C. HIGH PRESSURE SLOWLY BUILDS IN FROM THE WEST. THE
GFS AND ECMWF ARE IN FAIR AGREEMENT FRIDAY AND SATURDAY. FOR SUNDAY
THE 00Z ECMWF HANGS UNTO THE PRECIPITATION LONGER IN THE FORECAST
AREA. AT THIS TIME REMAINED CONSISTENT WITH THE PREVIOUS FORECAST
BUT THIS WILL HAVE TO BE WATCHED. TEMPERATURES WILL BE BELOW NORMAL.
THE THREAT OF FROST IS POSSIBLE SATURDAY NIGHT BUT ESPECIALLY SUNDAY
NIGHT IF THE CLOUDS DECREASE AS EXPECTED.
&&
.AVIATION /11Z MONDAY THROUGH FRIDAY/...
GUSTY WINDS AND A THREAT OF THUNDER ARE THE WEATHER PROBLEMS FOR
TODAY. THE SHOWERS OVER EASTERN INDIANA AND WESTERN OHIO ARE
DECREASING AS THEY MOVE EAST...THE HRRR MODEL CONCURS WITH THIS.
THE MODELS ARE TRYING TO FORECAST A NARROW SQUALL LINE DEVELOPING AHEAD
OF THE FRONT LATE THIS MORNING AND IT WILL MOVE EAST RAPIDLY. THINGS MAY
BE MOVING QUICKER AND THIS MAY LIMIT THE AMOUNT OF THUNDER AND
SEVERE WEATHER. THE BEST CHANCE FOR THUNDER IS FROM CLE EAST AS
THE AIRMASS WILL GET UNSTABLE ENOUGH. THE 00Z 4KM WRF-NMM HAS TWO
NARROW BANDS OF SHOWERS...ONE MOVES THROUGH BY EARLY AFTERNOON AND
THEN ANOTHER DEVELOPS LATE IN THE AFTERNOON. THE 4KM WRF IS THE
ONLY MODEL SHOWING THIS. ON THE EDGE ABOUT THIS.
THE PRESSURE GRADIENT INCREASED SO MOST PLACES ARE GUSTY...THUS
DECREASING THE THREAT OF SIGNIFICANT LOW LEVEL WIND SHEAR-LLWS.
THE HRRR MODEL INCREASES THE GUSTS AT THE SURFACE IN EXCESS OF 40
KNOTS BY NOON IN THE WARM ADVECTION. GETTING SOME SUNSHINE AT
TIMES WILL HELP. AT DAYBREAK SOME GUSTS TO 35 KNOTS WERE ALREADY
BEING REPORTED. THE WINDS WILL DECREASE AROUND SUNSET.
VFR FOR CLOUDS AND VISIBILITY EXCEPT IN SHOWERS AND THUNDERSTORMS.
HOWEVER...THE SREF IS TRYING TO INDICATE MVFR CEILINGS DEVELOPING
THIS MORNING AND ENDING THIS AFTERNOON. SOME MVFR CEILINGS HAVE
DEVELOPED IN INDIANA...BUT AS THE SHOWERS DECREASE...THE CLOUDS
MAY ALSO. WILL FORECAST SOME MVFR CEILINGS FOR TOL AND FDY.
.OUTLOOK...NON VFR POSSIBLE WEDNESDAY NIGHT INTO FRIDAY.
&&
.MARINE...
STRONG WARM ADVECTION WILL OCCUR THIS MORNING UNTIL THE COLD FRONT
BEGINS MOVING ACROSS LAKE ERIE FROM WEST TO EAST THIS AFTERNOON.
EVEN THOUGH PLENTY OF WARM AIR AND STRONG WINDS ALOFT...SUSTAINED
WINDS OF 20 TO 25 KNOTS WILL BE LIKELY LATER THIS MORNING AND THEN
BEHIND THE FRONT SUSTAINED WINDS OF 30 KNOTS WITH HIGHER GUSTS. SOME
CONCERN THAT ESPECIALLY ON THE EAST END THE WINDS COULD APPROACH
GALE FORCE. THE COLD ADVECTION IS NOT THAT SIGNIFICANT SO WILL
CONTINUE WITH THE 30 KNOTS SUSTAINED AND A SMALL CRAFT ADVISORY. THE
WINDS WILL DECREASE FROM WEST TO EAST TUESDAY AS HIGH PRESSURE
BUILDS IN. UNTIL THAT HAPPENS THE WATER LEVEL ON THE WEST END OF
LAKE ERIE COULD DROP LATE THIS AFTERNOON AND EVENING. AT THIS TIME
IT IS NOT EXPECTED TO DROP TO BELOW THE CRITICAL MARK FOR SAFE
NAVIGATION...THIS WILL BE WATCHED CLOSELY BY THE NEXT SHIFTS.
SOME MINOR THREAT THAT WAVES COULD APPROACH SMALL CRAFT ADVISORY ON
THURSDAY AFTER A COLD FRONTAL PASSAGE. AT THIS TIME 2 TO 4 FOOT
WAVES SEEM TO BE THE HIGHEST.
THE NEXT THREAT OF A SMALL CRAFT ADVISORY WILL BE FRIDAY NIGHT INTO
SUNDAY AS A LOW AND FRONT MOVES NEAR LAKE ERIE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...WIND ADVISORY UNTIL 10 PM EDT THIS EVENING FOR OHZ003-006>014-
017>023-027>033-036>038-047-089.
PA...WIND ADVISORY UNTIL 10 PM EDT THIS EVENING FOR PAZ001>003.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EDT TUESDAY FOR LEZ147>149.
SMALL CRAFT ADVISORY UNTIL 10 AM EDT TUESDAY FOR LEZ142>146.
&&
$$
SYNOPSIS...ADAMS
NEAR TERM...ADAMS
SHORT TERM...ADAMS
LONG TERM...KIELTYKA
AVIATION...KIELTYKA
MARINE...KIELTYKA
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
612 AM EDT MON APR 16 2012
.SYNOPSIS...
A COLD FRONT OVER INDIANA WILL MOVE EAST THROUGH THE AREA LATER
TODAY AND EARLY TONIGHT THEN HIGH PRESSURE WILL CROSS THE REGION
LATE TUESDAY INTO EARLY WEDNESDAY. ANOTHER COLD FRONT WILL DROP INTO
THE OHIO VALLEY EARLY THURSDAY AND STALL. LOW PRESSURE WILL MOVE
ALONG THE FRONT UP THE OHIO VALLEY FRIDAY AND TO THE MID ATLANTIC
COAST SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM MONDAY EVENING/...
INITIAL BAND OF WEAKENING SHRA/ISOLD TSRA SHOULD MOVE INTO THE NW
CO`S OVER THE NEXT HOUR OR TWO THEN PROGRESS EAST INTO MAINLY THE
EASTERN CO`S FOR THE AFTERNOON. WITH DAYTIME HEATING COULD SEE SOME
OF THE STORMS BECOME SEVERE IN THE EAST WITH DAMAGING WINDS AND TO A
LESSER EXTENT POSSIBLE LARGE HAIL OR A BRIEF TORNADO. COVERAGE OF
CONVECTION IN QUESTION SO WILL STAY WITH JUST CHANCE POPS WHICH IS
STILL HIGHER THAN MAV GUIDANCE.
THE WINDS WILL ALSO BE AN ISSUE OUTSIDE OF THE TSRA AS 850 MB WINDS
AT FRONTAL PASSAGE TIME LOOK TO BE 50 TO 55 KNOTS. AFTER
COLLABORATION HAVE DECIDED TO GO WITH WIND ADVISORY VERSUS WIND
WARNING.
&&
.SHORT TERM /6 PM MONDAY EVENING THROUGH THURSDAY NIGHT/...
HIGH PRESSURE BUILDS IN FROM THE WEST TONIGHT SO STRONG WINDS WILL
DIMINISH FROM WEST TO EAST DURING THE EVENING BUT COULD STILL REMAIN
A LITTLE WINDY FOR THE SNOWBELT LAKESHORE INTO THE LATE NIGHT HOURS.
DRY PUNCH OF AIR BEHIND THE COLD FRONT SHIFTS INTO THE EAST DURING
THE EVENING. WRAP MOISTURE TRIES TO SPREAD EAST INTO THE CWA EARLY
TONIGHT BUT SUBSIDENCE WITH HIGH MOVING IN LOOKS TO BE TOO STRONG TO
ALLOW FOR ENOUGH CLOUDINESS TO PRODUCE ANY PRECIP.
HIGH PRESSURE WITH DRY CONDITIONS SHOULD OCCUR INTO WED NIGHT THEN
ANOTHER COLD FRONT WILL MOVE IN BRINGING A THREAT FOR SHRA MAINLY
FOR THE SECOND HALF OF WED NIGHT.
THE QUESTION FOR THU IS WHETHER THE FRONT WILL HAVE ENOUGH MOMENTUM
TO PUSH FAR ENOUGH S TO TAKE THE SHRA THREAT SOUTH OF THE CWA FOR
THU AFTERNOON AND EVENING. LOW PRESSURE WILL MOVE ALONG THE FRONT
AND SPREAD SHRA BACK NORTH OF THE FRONT THU NIGHT. RIGHT NOW MODELS
WANT TO KEEP GOOD DEEP MOISTURE OVER THE CWA LATE THU AND THU NIGHT
SO WILL SIDE WITH CAUTION AND KEEP THREAT FOR SHRA GOING ALL DAY THU
AS WELL AS THU NIGHT.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
ANOTHER COLD FRONT MOVES THROUGH ON FRIDAY WITH A FAIR AMOUNT OF
COLD AIR BEHIND IT. THE LAKE AND 850 MB TEMPERATURE DIFFERENCE WILL
BE NEAR 11 OR 12C. HIGH PRESSURE SLOWLY BUILDS IN FROM THE WEST. THE
GFS AND ECMWF ARE IN FAIR AGREEMENT FRIDAY AND SATURDAY. FOR SUNDAY
THE 00Z ECMWF HANGS UNTO THE PRECIPITATION LONGER IN THE FORECAST
AREA. AT THIS TIME REMAINED CONSISTENT WITH THE PREVIOUS FORECAST
BUT THIS WILL HAVE TO BE WATCHED. TEMPERATURES WILL BE BELOW NORMAL.
THE THREAT OF FROST IS POSSIBLE SATURDAY NIGHT BUT ESPECIALLY SUNDAY
NIGHT IF THE CLOUDS DECREASE AS EXPECTED.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
GUSTY WINDS AND A THREAT OF THUNDER ARE THE WEATHER PROBLEMS FOR
TODAY. THE SHOWERS AND THUNDERSTORMS OVER INDIANA AND ILLINOIS ARE
DECREASING...HRRR MODEL CONCURS WITH THIS. A NARROW SQUALL LINE
DEVELOPS AHEAD OF THE FRONT LATE THIS MORNING AND MOVES EAST. THE
BEST CHANCE FOR THUNDER IS FROM CLE AND MFD EAST AS THE AIRMASS
WILL GET UNSTABLE ENOUGH.
THE PRESSURE GRADIENT WILL INCREASE DURING THE EARLY MORNING HOURS
AS THE WINDS ALOFT AT 925 MB AND 850 MB INCREASE IN EXCESS OF 50
KNOTS. AS THE WINDS AS THE SURFACE BECOME GUSTY THIS SHOULD
DECREASE THE THREAT OF LLWS. THE HRRR MODEL INCREASES THE GUSTS AT
THE SURFACE IN EXCESS OF 40 KNOTS BY NOON IN THE WARM ADVECTION.
IF WE CAN GET SOME SUNSHINE AND WE SHOULD THAT MAY BE OK. THE
WINDS WILL DECREASE AROUND SUNSET.
VFR FOR CLOUDS AND VISIBILITY EXCEPT IN SHOWERS AND THUNDERSTORMS.
HOWEVER...THE SREF IS TRYING TO INDICATE MVFR CEILINGS DEVELOPING
THIS MORNING AND ENDING THIS AFTERNOON. NOT REAL SURE OF
THIS...WILL NOT FORECAST IT ATTM.
.OUTLOOK...NON-VFR CONDITIONS POSSIBLE LATE MONDAY NIGHT INTO
TUESDAY AND THEN AGAIN WEDNESDAY NIGHT INTO FRIDAY.
&&
.MARINE...
STRONG WARM ADVECTION WILL OCCUR THIS MORNING UNTIL THE COLD FRONT
BEGINS MOVING ACROSS LAKE ERIE FROM WEST TO EAST THIS AFTERNOON.
EVEN THOUGH PLENTY OF WARM AIR AND STRONG WINDS ALOFT...SUSTAINED
WINDS OF 20 TO 25 KNOTS WILL BE LIKELY LATER THIS MORNING AND THEN
BEHIND THE FRONT SUSTAINED WINDS OF 30 KNOTS WITH HIGHER GUSTS. SOME
CONCERN THAT ESPECIALLY ON THE EAST END THE WINDS COULD APPROACH
GALE FORCE. THE COLD ADVECTION IS NOT THAT SIGNIFICANT SO WILL
CONTINUE WITH THE 30 KNOTS SUSTAINED AND A SMALL CRAFT ADVISORY. THE
WINDS WILL DECREASE FROM WEST TO EAST TUESDAY AS HIGH PRESSURE
BUILDS IN. UNTIL THAT HAPPENS THE WATER LEVEL ON THE WEST END OF
LAKE ERIE COULD DROP LATE THIS AFTERNOON AND EVENING. AT THIS TIME
IT IS NOT EXPECTED TO DROP TO BELOW THE CRITICAL MARK FOR SAFE
NAVIGATION...THIS WILL BE WATCHED CLOSELY BY THE NEXT SHIFTS.
SOME MINOR THREAT THAT WAVES COULD APPROACH SMALL CRAFT ADVISORY ON
THURSDAY AFTER A COLD FRONTAL PASSAGE. AT THIS TIME 2 TO 4 FOOT
WAVES SEEM TO BE THE HIGHEST.
THE NEXT THREAT OF A SMALL CRAFT ADVISORY WILL BE FRIDAY NIGHT INTO
SUNDAY AS A LOW AND FRONT MOVES NEAR LAKE ERIE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...WIND ADVISORY FROM 10 AM THIS MORNING TO 10 PM EDT THIS
EVENING FOR OHZ003-006>014-017>023-027>033-036>038-047-
089.
PA...WIND ADVISORY FROM 10 AM THIS MORNING TO 10 PM EDT THIS
EVENING FOR PAZ001>003.
MARINE...SMALL CRAFT ADVISORY FROM 9 AM THIS MORNING TO 4 PM
EDT TUESDAY FOR LEZ147>149.
SMALL CRAFT ADVISORY FROM 9 AM THIS MORNING TO 10 AM EDT
TUESDAY FOR LEZ142>146.
&&
$$
SYNOPSIS...ADAMS
NEAR TERM...ADAMS
SHORT TERM...ADAMS
LONG TERM...KIELTYKA
AVIATION...KIELTYKA
MARINE...KIELTYKA
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1121 AM MDT MON APR 16 2012
.UPDATE...WEAK BOUNDARY NOTED ACROSS LINCOLN AND EASTERN
WASHINGTON COUNTIES AS SHORTWAVE EXITS REGION. ECHOES CURRENTLY
DEVELOPING ALONG THE BOUNDARY WITH CAPES CURRENTLY AROUND 400
J/KG. SO SOME POTENTIAL FOR THUNDER IN THIS REGION. DRIER AIR
BEGINNING TO SPREAD ACROSS WESTERN PORTIONS OF THE CFWA AS NOTED
BY A DECREASE IN SHOWER ACTIVITY. MOUNTAIN WEB CAM HAVE ALSO SHOWN
A MARKED DECREASE. MODELS CONTINUE TO DRY OUT THE
REGION...ALTHOUGH HRRR AND RUC INDICATE SOME WEAK SHOWERS THROUGH
THE AFTERNOON ACROSS THE FAR NORTHEAST PLAINS WITH MINIMAL CAPES.
WILL BE LOWERING SHOWER CHANCES FOR THIS AFTERNOON...WITH A SLIGHT
CHANCE FOR THUNDER THROUGH 21Z. WILL ALSO DROP THE MENTION OF
SNOW. DRY CONDITIONS LOOK GOOD FOR THIS EVENING.
&&
.AVIATION...WINDS SHOULD REMAIN NORTHWESTERLY THROUGH THE
AFTERNOON AS THERE IS NO HINT OF ANY CYCLONE DEVELOPING. ANY
SHOWER ACTIVITY SHOULD STAY WELL EAST OF THE AREA AIRPORTS. WILL
MAINTAIN CURRENT TAF TRENDS FOR THE NEXT ISSUANCE.
&&
.PREV DISCUSSION... /ISSUED 435 AM MDT SUN APR 15 2012/
SHORT TERM...BATCH OF SHOWERS FROM WELD COUNTY INTO THE CENTRAL
MOUNTAINS WILL CONTINUE TO MOVE EAST THIS MORNING. IT LOOKS LIKE
THE MAIN AREA HAS MISSED DENVER...BUT I WILL ADJUST POPS A LITTLE
BIT IN ACCORDANCE WITH THE PATH OF THIS SHOWER BAND. WARMING AND
DRYING TODAY...BUT WITH COOL TEMPERATURES ALOFT WE SHOULD HAVE MORE
CONVECTION DEVELOP THIS AFTERNOON. WITH THE DRYING...CAPES WILL BE
LOWER...GENERALLY AROUND 500 J/KG...SO NOT EXPECTING HAIL BUT I WILL
ADD BACK SOME THUNDER OUT ON THE PLAINS. STILL THINK THE CHANCE OF
MEASURABLE RAIN IN DENVER IS TOO LOW TO MENTION. WITH CLEARING
SKIES TONIGHT AND DRIER AIR IT WILL BE A COOL NIGHT...LOWERED THE
LOW TEMPERATURES 3 DEGREES TO MATCH GUIDANCE TEMPS.
LONG TERM...MODELS HAVE WEST-NORTHWESTERLY FLOW ALOFT FOR THE CWA
TUESDAY INTO TUESDAY NIGHT. ZONAL FLOW TAKES OVER EARLY WEDNESDAY
MORNING INTO WEDNESDAY EVENING...THEN A WEAK UPPER TROUGH IS PROGGED
TO MOVE ACROSS THE CWA BY EARLY THURSDAY. THE SYNOPTIC SCALE ENERGY
IS NONDESCRIPT TUESDAY AND TUESDAY NIGHT. WEAK UPWARD QG VERTICAL
VELOCITY IS PROGGED FOR THE FORECAST AREA WEDNESDAY AND WEDNESDAY
EVENING. WEAK DOWNSLOPING TO NORMAL DIURNAL WIND PATTERNS ARE
PROGGED IN THE LOW LEVELS TUESDAY. NORMAL PATTERNS SHOULD PREVAIL
TUESDAY NIGHT INTO WEDNESDAY...WITH SOUTHEASTERLIES WEDNESDAY
AFTERNOON...THEN NORTH-NORTHWESTERLIES WEDNESDAY NIGHT. FOR
MOISTURE...MODELS HAVE QUITE A BIT TUESDAY THROUGH WEDNESDAY NIGHT
..BUT IT IS MOSTLY IN THE MID AND UPPER LEVELS. WEDNESDAY NIGHT
..MOISTURE IS FAIRLY DEEP OVER THE MOUNTAINS. BOUNDARY LAYER DEW
POINT FIELDS SHOW TEENS TO MID 20S F READINGS TUESDAY. THEY COME UP
A BIT TUESDAY NIGHT AND WEDNESDAY...WITH THEM GETTING INTO 30S TO
LOWER 40S F BY WEDNESDAY EVENING. THERE IS A BIT OF CAPE AROUND
LATER WEDNESDAY AFTERNOON...AND LAPSE RATES ARE PRETTY STEEP BELOW
400 MB. THE QPF FIELDS SHOW A TAD OF MEASURABLE PRECIPITATION
TUESDAY AFTERNOON/EVENING MAINLY OVER THE MOUNTAINS. THEY SHOW
SMALL AMOUNTS WEDNESDAY AFTERNOON AND NIGHT...MAINLY OVER THE
MOUNTAINS AND EASTERN HALF OF THE PLAINS. FOR POPS...WILL GO
"SLIGHT CHANCE" IN THE HIGH MOUNTAINS TUESDAY AFTERNOON. FOR
WEDNESDAY AFTERNOON AND NIGHT...WILL GO 20-40%S IN THE MOUNTAINS AND
10-20%S OUT ON THE PLAINS. FOR TEMPERATURES...TUESDAY`S HIGHS ARE
PROGGED TO WARM-UP 3-7 C FROM TODAY`S. WEDNESDAY`S HIGHS ARE 1-2 C
WARMER THAN TUESDAY`S. FOR THE LATER DAYS...THURSDAY THROUGH SUNDAY
..THERE IS NORTHWESTERLY FLOW ALOFT PROGGED ON THURSDAY...THEN A
STRONG NORTHERLY JET MAXIMUM IS PROGGED TO MOVE OVER THE CWA LATER
THURSDAY NIGHT INTO MIDDAY FRIDAY. AFTER THAT...THE FLOW ALOFT
DECREASES AND IS NORTHWESTERLY AS AN UPPER RIDGE TO THE WEST MOVES
SLOWLY THIS WAY. THERE IS SOME MOISTURE AROUND THURSDAY AND
FRIDAY...SATURDAY AND SUNDAY ARE DRY. TEMPERATURES WILL BE NEAR
SEASONAL NORMALS THURSDAY AND FRIDAY...THEN WARM-UP SATURDAY AND
SUNDAY.
AVIATION...VFR CONDITIONS ARE EXPECTED THROUGH TONIGHT. THERE WILL
BE ISOLATED SHOWERS DURING THE EARLY MORNING...WITH A CHANCE OF
NEEDING INSTRUMENT APPROACHES TO KDEN UNTIL ABOUT 15Z. ISOLATED
SHOWERS MAY REDEVELOP THIS AFTERNOON...BUT CEILINGS WILL BE HIGHER.
WINDS WILL HAVE SOME VARIABILITY EARLY THIS MORNING DUE TO THE
SHOWERS...THEN SHIFT TO THE NORTH TO NORTHWEST BY LATE MORNING.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...D-L
LONG TERM....RJK
AVIATION...D-L
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
552 PM CDT MON APR 16 2012
...UPDATED FOR THE 00Z TAF ISSUANCE...
.SHORT TERM...(THIS EVENING THROUGH TOMORROW)
ISSUED AT 212 PM CDT MON APR 16 2012
SYNOPSIS:
THE 16 APRIL 2012 12Z SYNOPTIC MAPS SHOWED A STRONG 125 KT TO 135 KT
300 HPA JET ACROSS MISSOURI. ANOTHER 300 HPA JET STREAK WAS LOCATED
ACROSS QUEBEC. FURTHER UPSTREAM, A 50 KT TO 70 KT 300 HPA JET WAS LOCATED
ACROSS THE PACIFIC NORTHWEST. AT 500 HPA, A MINOR SHORTWAVE TROUGH WAS
MOVING ACROSS THE ROCKIES. MOISTURE ADVECTION DOWNSTREAM OF A 536 DM
LOW WAS OBSERVED ACROSS THE UPPER GREAT LAKES AND INTO THE OHIO RIVER
VALLEY. IN ADDITION, SOME MID LEVEL MOISTURE WAS PUSHING ONSHORE ACROSS
OREGON/WASHINGTON. AT 700 HPA, A RELATIVELY COOL AND DRY AIRMASS HAS
SPREAD OVER THE PLAINS IN THE WAKE OF A DEPARTING SYSTEM. AT 850 HPA,
SOME WRAP AROUND MOISTURE WAS OBSERVED ACROSS MINNESOTA AND STRETCHING
DOWN TO EASTERN KANSAS IN ASSOCIATION WITH A LOW TO MID LEVEL CYCLONE
TO THE NORTHEAST. AT THE SFC, A COLD FRONT WAS ANALYZED FROM SE ONTARIO
TO TEXAS. ANY GULF OF MEXICO MOISTURE WAS SOUTH OF THIS BOUNDARY.
TONIGHT:
VISIBLE SATELLITE AND WSR-88D TRENDS HAVE BEEN ECHOING MODEL OUTPUT,
PARTICULARLY FROM THE HRRR. AS A RESULT, HAVE RELIED HEAVILY ON THIS
MODEL FOR TONIGHT. AN UPPER LEVEL SHORTWAVE TROUGH/400 HPA PV ANOMALY
WILL MOVE ACROSS SOUTHWEST KANSAS THIS EVENING. CONVECTION HAS FORMED
ACROSS SOUTHEAST COLORADO AS A RESULT. EVEN THOUGH DEWPOINTS ARE RUNNING
ONLY IN THE 30S DEG F RANGE, THE HRRR SHOWS SOME WEAK INSTABILITY FORMING.
THIS IS ECHOED IN FORECAST SOUNDINGS ACROSS MY COUNTY WARNING AREA.
100-300 J/KG OF CAPE ALONG WITH FAIRLY STEEP 700 HPA TO 500 HPA WILL
LEAD TO EASTWARD PROPAGATING SHOWERS AND ISOLATED THUNDERSTORMS THROUGH
THE REST OF THIS AFTERNOON AND INTO THE EARLY EVENING. SEVERE WEATHER
IS NOT EXPECTED DUE TO WEAK INSTABILITY/SHEAR. OVERNIGHT LOWS WILL BE SLIGHTLY
WARMER WITH MID 30S DEG F OUT WEST AND MID 40S DEG F ACROSS SOUTH CENTRAL
KANSAS. THE 12Z NAM WAS SHOWING INCREASING 1000-850 HPA MOISTURE, BUT
THINK THIS IS AN OUTLIER COMPARED TO THE REST OF THE MODELS. THE MAIN
IMPLICATIONS FROM THIS WOULD BE AREAS OF STRATUS AND SLIGHTLY WARMER
MINIMUMS UNDER THE CLOUD DECK. WILL HOLD OFF FOR NOW ON THIS SOLUTION.
TOMORROW:
FLAT 500 HPA RIDGING IS EXPECTED ACROSS THE ROCKIES AND HIGH PLAINS
TOMORROW. THIS WILL LEAD TO WESTERLY FLOW ALOFT AND DOWNSLOPE SOUTHWESTERLY
SURFACE TO 600 HPA WINDS. THE ATMOSPHERE BECOMES DEEPLY MIXED TO ABOUT
650 HPA WHICH SUPPORTS WARMER MAXIMUM TEMPERATURES FOR TOMORROW VIA
ADIABATIC COMPRESSIONAL WARMING. THE WIND PROFILE WITHIN THIS LAYER
IS NOT PARTICULARLY STRONG, BUT I DO THINK BREEZY CONDITIONS ARE EXPECTED
AS MIXING AND RESULTANT MOMENTUM TRANSFER DEVELOPS/CONTINUES TOMORROW.
HIGHS WILL BE IN THE 70S DEG F RANGE. NO PRECIPITATION IS EXPECTED AS
SUBSIDENCE IN THE WAKE OF THE TROUGH PREVAILS. A LEE SURFACE TROUGH
ACROSS EASTERN COLORADO WILL CONTINUE AS WELL WITH THE AFOREMENTIONED
PERPENDICULAR FLOW TO THE ROCKIES.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 219 PM CDT MON APR 16 2012
WESTERLY DOWNSLOPE FLOW BEGINS TO IMPROVE TOWARDS MID WEEK AS AN
UPPER LEVEL TROUGH EMBEDDED IN THIS FLOW MOVES QUICKLY EASTWARD
TOWARDS THE NORTHERN PLAINS. THIS UPPER LEVEL TROUGH WILL CROSS OUT
INTO THE PLAINS LATE TUESDAY AND AS IT DOES A SURFACE BOUNDARY WILL
MOVE EAST INTO WESTERN KANSAS. JET UPPER LEVEL DYNAMICS APPEAR
LACKING ACROSS WESTERN KANSAS LATE TUESDAY, HOWEVER THERE WILL BE
SOME FORCING DEVELOPING LATE DAY NEAR THIS BOUNDARY THAT WILL BE
LOCATED NEAR WAKEENEY AND DODGE CITY. AT THIS TIME PRECIPITATION
CHANCES TUESDAY NIGHT STILL APPEARS VERY LOW BASED ON THE WEAK
FORCING ALOFT AND WARMING TEMPERATURES IN THE 850-700MB LAYER WHICH
SHOULD SERVE AS A CAP. AS A RESULT WILL CONTINUE TO FAVOR A DRY
FORECAST TUESDAY NIGHT BUT GIVEN THE RETURN OF NEAR 50 DEGREE
SURFACE DEWPOINTS RETURNING ACROSS SOUTH CENTRAL KANSAS WILL
CONTINUE TO FAVOR THE WARMER PREVIOUS FORECAST FOR LOWS WHICH THE
MET NOW APPEARS TO HINTING AT.
THE NEXT IN A SERIES OF UPPER LEVEL DISTURBANCES WILL THEN CROSS OUT
INTO THE PLAINS ON LATE WEDNESDAY AS WARM AIR ADVECTION IMPROVES
NORTH OF A SURFACE BOUNDARY THAT WILL EXTEND FROM WEST TO EAST
ACROSS NORTHERN KANSAS. THIS CONVECTION SHOULD STAY NORTH OF THE I70
CORRIDOR. BASED ON THE NEW 850MB TEMPERATURE TRENDS FROM THE NAM AND
GFS WILL GO AHEAD AN WARM TEMPERATURES UP INTO THE 80 TO 85 DEGREE
RANGE FOR MUCH OF SOUTHWEST KANSAS.
BY LATE WEEK AN UPPER LEVEL RIDGE IS EXPECTED TO DEVELOP ACROSS THE
WESTERN UNITED STATES AS AN UPPER LOW NEAR THE GULF OF ALASKA BEGINS
TO DROP SOUTH/SOUTHEAST. THE NEXT UPPER LEVEL TROUGH WILL MOVE OUT
INTO THE PLAINS ON THURSDAY WHICH WILL ALLOW THE FRONT ACROSS
NORTHERN KANSAS TO CROSS INTO NORTHERN OKLAHOMA BY THURSDAY EVENING.
MOIST UPSLOPE FLOW DEVELOPING NORTH OF THIS FRONT COMBINED WITH THE
LEFT EXIT REGION OF AN UPPER LEVEL JET ROTATING AROUND THIS
DEVELOPING UPPER RIDGE WILL ENHANCE THUNDERSTORM CHANCES ACROSS MUCH
OF WESTERN KANSAS THURSDAY NIGHT. THESE PRECIPITATION CHANCES WILL
END FROM WEST TO EAST EARLY FRIDAY AS THE UPPER RIDGE LOCATED OVER
THE WEST COAST STARTS TO SHIFT EASTWARD TOWARDS THE ROCKIES. AS FOR
TEMPERATURES LATE WEEK AND OVER THE WEEKEND PERIOD...AFTER A COOL
DOWN BEHIND THE FRONT THURSDAY NIGHT AND FRIDAY A WARMING TREND WILL
BEGIN FOR THE WEEKEND PERIOD.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 546 PM CDT MON APR 16 2012
A SMALL BAND OF SHOWERS WILL MOVE ACROSS THE TAF SITES EARLY THIS
EVENING. AS THE SHOWERS TRANSVERSE EAST, CIGS MAY LOWER TO THE
OVC050-060CB CATEGORY. WINDS WILL BE LIGHT SOUTHEAST THIS
EVENING, BECOME SOUTH AND LIGHT UNDER 06KTS AFTER SUNDOWN. SKIES
WILL BECOME CLEAR BY MIDNIGHT AS WELL. EXPECT SOUTHWEST WINDS BY
10AM TUESDAY MORNING IN THE BREEZY 15G25KT RANGE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 44 77 48 80 / 80 0 10 0
GCK 41 75 45 80 / 70 0 0 0
EHA 38 77 46 82 / 20 0 0 0
LBL 41 78 47 83 / 80 0 10 0
HYS 42 74 48 77 / 50 0 10 0
P28 46 74 52 80 / 50 0 10 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...SUGDEN
LONG TERM...BURGERT
AVIATION...BURKE
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
224 PM CDT MON APR 16 2012
...UPDATED LONG TERM DISCUSSION...
.SHORT TERM...(THIS EVENING THROUGH TOMORROW)
ISSUED AT 212 PM CDT MON APR 16 2012
SYNOPSIS:
THE 16 APRIL 2012 12Z SYNOPTIC MAPS SHOWED A STRONG 125 KT TO 135 KT
300 HPA JET ACROSS MISSOURI. ANOTHER 300 HPA JET STREAK WAS LOCATED
ACROSS QUEBEC. FURTHER UPSTREAM, A 50 KT TO 70 KT 300 HPA JET WAS LOCATED
ACROSS THE PACIFIC NORTHWEST. AT 500 HPA, A MINOR SHORTWAVE TROUGH WAS
MOVING ACROSS THE ROCKIES. MOISTURE ADVECTION DOWNSTREAM OF A 536 DM
LOW WAS OBSERVED ACROSS THE UPPER GREAT LAKES AND INTO THE OHIO RIVER
VALLEY. IN ADDITION, SOME MID LEVEL MOISTURE WAS PUSHING ONSHORE ACROSS
OREGON/WASHINGTON. AT 700 HPA, A RELATIVELY COOL AND DRY AIRMASS HAS
SPREAD OVER THE PLAINS IN THE WAKE OF A DEPARTING SYSTEM. AT 850 HPA,
SOME WRAP AROUND MOISTURE WAS OBSERVED ACROSS MINNESOTA AND STRETCHING
DOWN TO EASTERN KANSAS IN ASSOCIATION WITH A LOW TO MID LEVEL CYCLONE
TO THE NORTHEAST. AT THE SFC, A COLD FRONT WAS ANALYZED FROM SE ONTARIO
TO TEXAS. ANY GULF OF MEXICO MOISTURE WAS SOUTH OF THIS BOUNDARY.
TONIGHT:
VISIBLE SATELLITE AND WSR-88D TRENDS HAVE BEEN ECHOING MODEL OUTPUT,
PARTICULARLY FROM THE HRRR. AS A RESULT, HAVE RELIED HEAVILY ON THIS
MODEL FOR TONIGHT. AN UPPER LEVEL SHORTWAVE TROUGH/400 HPA PV ANOMALY
WILL MOVE ACROSS SOUTHWEST KANSAS THIS EVENING. CONVECTION HAS FORMED
ACROSS SOUTHEAST COLORADO AS A RESULT. EVEN THOUGH DEWPOINTS ARE RUNNING
ONLY IN THE 30S DEG F RANGE, THE HRRR SHOWS SOME WEAK INSTABILITY FORMING.
THIS IS ECHOED IN FORECAST SOUNDINGS ACROSS MY COUNTY WARNING AREA.
100-300 J/KG OF CAPE ALONG WITH FAIRLY STEEP 700 HPA TO 500 HPA WILL
LEAD TO EASTWARD PROPAGATING SHOWERS AND ISOLATED THUNDERSTORMS THROUGH
THE REST OF THIS AFTERNOON AND INTO THE EARLY EVENING. SEVERE WEATHER
IS NOT EXPECTED DUE TO WEAK INSTABILITY/SHEAR. OVERNIGHT LOWS WILL BE SLIGHTLY
WARMER WITH MID 30S DEG F OUT WEST AND MID 40S DEG F ACROSS SOUTH CENTRAL
KANSAS. THE 12Z NAM WAS SHOWING INCREASING 1000-850 HPA MOISTURE, BUT
THINK THIS IS AN OUTLIER COMPARED TO THE REST OF THE MODELS. THE MAIN
IMPLICATIONS FROM THIS WOULD BE AREAS OF STRATUS AND SLIGHTLY WARMER
MINIMUMS UNDER THE CLOUD DECK. WILL HOLD OFF FOR NOW ON THIS SOLUTION.
TOMORROW:
FLAT 500 HPA RIDGING IS EXPECTED ACROSS THE ROCKIES AND HIGH PLAINS
TOMORROW. THIS WILL LEAD TO WESTERLY FLOW ALOFT AND DOWNSLOPE SOUTHWESTERLY
SURFACE TO 600 HPA WINDS. THE ATMOSPHERE BECOMES DEEPLY MIXED TO ABOUT
650 HPA WHICH SUPPORTS WARMER MAXIMUM TEMPERATURES FOR TOMORROW VIA
ADIABATIC COMPRESSIONAL WARMING. THE WIND PROFILE WITHIN THIS LAYER
IS NOT PARTICULARLY STRONG, BUT I DO THINK BREEZY CONDITIONS ARE EXPECTED
AS MIXING AND RESULTANT MOMENTUM TRANSFER DEVELOPS/CONTINUES TOMORROW.
HIGHS WILL BE IN THE 70S DEG F RANGE. NO PRECIPITATION IS EXPECTED AS
SUBSIDENCE IN THE WAKE OF THE TROUGH PREVAILS. A LEE SURFACE TROUGH
ACROSS EASTERN COLORADO WILL CONTINUE AS WELL WITH THE AFOREMENTIONED
PERPENDICULAR FLOW TO THE ROCKIES.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 219 PM CDT MON APR 16 2012
WESTERLY DOWNSLOPE FLOW BEGINS TO IMPROVE TOWARDS MID WEEK AS AN
UPPER LEVEL TROUGH EMBEDDED IN THIS FLOW MOVES QUICKLY EASTWARD
TOWARDS THE NORTHERN PLAINS. THIS UPPER LEVEL TROUGH WILL CROSS OUT
INTO THE PLAINS LATE TUESDAY AND AS IT DOES A SURFACE BOUNDARY WILL
MOVE EAST INTO WESTERN KANSAS. JET UPPER LEVEL DYNAMICS APPEAR
LACKING ACROSS WESTERN KANSAS LATE TUESDAY, HOWEVER THERE WILL BE
SOME FORCING DEVELOPING LATE DAY NEAR THIS BOUNDARY THAT WILL BE
LOCATED NEAR WAKEENEY AND DODGE CITY. AT THIS TIME PRECIPITATION
CHANCES TUESDAY NIGHT STILL APPEARS VERY LOW BASED ON THE WEAK
FORCING ALOFT AND WARMING TEMPERATURES IN THE 850-700MB LAYER WHICH
SHOULD SERVE AS A CAP. AS A RESULT WILL CONTINUE TO FAVOR A DRY
FORECAST TUESDAY NIGHT BUT GIVEN THE RETURN OF NEAR 50 DEGREE
SURFACE DEWPOINTS RETURNING ACROSS SOUTH CENTRAL KANSAS WILL
CONTINUE TO FAVOR THE WARMER PREVIOUS FORECAST FOR LOWS WHICH THE
MET NOW APPEARS TO HINTING AT.
THE NEXT IN A SERIES OF UPPER LEVEL DISTURBANCES WILL THEN CROSS OUT
INTO THE PLAINS ON LATE WEDNESDAY AS WARM AIR ADVECTION IMPROVES
NORTH OF A SURFACE BOUNDARY THAT WILL EXTEND FROM WEST TO EAST
ACROSS NORTHERN KANSAS. THIS CONVECTION SHOULD STAY NORTH OF THE I70
CORRIDOR. BASED ON THE NEW 850MB TEMPERATURE TRENDS FROM THE NAM AND
GFS WILL GO AHEAD AN WARM TEMPERATURES UP INTO THE 80 TO 85 DEGREE
RANGE FOR MUCH OF SOUTHWEST KANSAS.
BY LATE WEEK AN UPPER LEVEL RIDGE IS EXPECTED TO DEVELOP ACROSS THE
WESTERN UNITED STATES AS AN UPPER LOW NEAR THE GULF OF ALASKA BEGINS
TO DROP SOUTH/SOUTHEAST. THE NEXT UPPER LEVEL TROUGH WILL MOVE OUT
INTO THE PLAINS ON THURSDAY WHICH WILL ALLOW THE FRONT ACROSS
NORTHERN KANSAS TO CROSS INTO NORTHERN OKLAHOMA BY THURSDAY EVENING.
MOIST UPSLOPE FLOW DEVELOPING NORTH OF THIS FRONT COMBINED WITH THE
LEFT EXIT REGION OF AN UPPER LEVEL JET ROTATING AROUND THIS
DEVELOPING UPPER RIDGE WILL ENHANCE THUNDERSTORM CHANCES ACROSS MUCH
OF WESTERN KANSAS THURSDAY NIGHT. THESE PRECIPITATION CHANCES WILL
END FROM WEST TO EAST EARLY FRIDAY AS THE UPPER RIDGE LOCATED OVER
THE WEST COAST STARTS TO SHIFT EASTWARD TOWARDS THE ROCKIES. AS FOR
TEMPERATURES LATE WEEK AND OVER THE WEEKEND PERIOD...AFTER A COOL
DOWN BEHIND THE FRONT THURSDAY NIGHT AND FRIDAY A WARMING TREND WILL
BEGIN FOR THE WEEKEND PERIOD.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1230 PM CDT MON APR 16 2012
MAIN CONCERN FOR THE 18Z TAFS IS THE POSSIBILITY OF SHOWERS THIS AFTERNOON.
CIGS WILL REMAIN PRIMARILY VFR THROUGH THE PERIOD. DID INSERT VCSH FOR
THE TERMINALS THIS AFTERNOON. IF IT DOESN`T PRECIPITATE THEN AT LEAST
AN INCREASE OF CUMULUS IS EXPECTED LATER AS A MINOR UL SHORTWAVE TROUGH
SKIRTS ACROSS THE REGION.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 44 77 48 78 / 30 0 0 0
GCK 41 75 45 77 / 30 0 0 0
EHA 38 77 46 81 / 20 0 0 0
LBL 41 78 47 81 / 30 0 0 0
HYS 42 74 48 75 / 30 0 10 0
P28 46 74 52 79 / 20 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...SUGDEN
LONG TERM...BURGERT
AVIATION...SUGDEN
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
212 PM CDT MON APR 16 2012
...UPDATED SYNOPSIS AND SHORT TERM DISCUSSIONS...
.SYNOPSIS...
ISSUED AT 212 PM CDT MON APR 16 2012
THE 16 APRIL 2012 12Z SYNOPTIC MAPS SHOWED A STRONG 125 KT TO 135 KT
300 HPA JET ACROSS MISSOURI. ANOTHER 300 HPA JET STREAK WAS LOCATED
ACROSS QUEBEC. FURTHER UPSTREAM, A 50 KT TO 70 KT 300 HPA JET WAS LOCATED
ACROSS THE PACIFIC NORTHWEST. AT 500 HPA, A MINOR SHORTWAVE TROUGH WAS
MOVING ACROSS THE ROCKIES. MOISTURE ADVECTION DOWNSTREAM OF A 536 DM
LOW WAS OBSERVED ACROSS THE UPPER GREAT LAKES AND INTO THE OHIO RIVER
VALLEY. IN ADDITION, SOME MID LEVEL MOISTURE WAS PUSHING ONSHORE ACROSS
OREGON/WASHINGTON. AT 700 HPA, A RELATIVELY COOL AND DRY AIRMASS HAS
SPREAD OVER THE PLAINS IN THE WAKE OF A DEPARTING SYSTEM. AT 850 HPA,
SOME WRAP AROUND MOISTURE WAS OBSERVED ACROSS MINNESOTA AND STRETCHING
DOWN TO EASTERN KANSAS IN ASSOCIATION WITH A LOW TO MID LEVEL CYCLONE
TO THE NORTHEAST. AT THE SFC, A COLD FRONT WAS ANALYZED FROM SE ONTARIO
TO TEXAS. ANY GULF OF MEXICO MOISTURE WAS SOUTH OF THIS BOUNDARY.
&&
.SHORT TERM...(THIS EVENING THROUGH TOMORROW)
ISSUED AT 212 PM CDT MON APR 16 2012
TONIGHT:
VISIBLE SATELLITE AND WSR-88D TRENDS HAVE BEEN ECHOING MODEL OUTPUT,
PARTICULARLY FROM THE HRRR. AS A RESULT, HAVE RELIED HEAVILY ON THIS
MODEL FOR TONIGHT. AN UPPER LEVEL SHORTWAVE TROUGH/400 HPA PV ANOMALY
WILL MOVE ACROSS SOUTHWEST KANSAS THIS EVENING. CONVECTION HAS FORMED
ACROSS SOUTHEAST COLORADO AS A RESULT. EVEN THOUGH DEWPOINTS ARE RUNNING
ONLY IN THE 30S DEG F RANGE, THE HRRR SHOWS SOME WEAK INSTABILITY FORMING.
THIS IS ECHOED IN FORECAST SOUNDINGS ACROSS MY COUNTY WARNING AREA.
100-300 J/KG OF CAPE ALONG WITH FAIRLY STEEP 700 HPA TO 500 HPA WILL
LEAD TO EASTWARD PROPAGATING SHOWERS AND ISOLATED THUNDERSTORMS THROUGH
THE REST OF THIS AFTERNOON AND INTO THE EARLY EVENING. SEVERE WEATHER
IS NOT EXPECTED DUE TO WEAK INSTABILITY/SHEAR. OVERNIGHT LOWS WILL BE SLIGHTLY
WARMER WITH MID 30S DEG F OUT WEST AND MID 40S DEG F ACROSS SOUTH CENTRAL
KANSAS. THE 12Z NAM WAS SHOWING INCREASING 1000-850 HPA MOISTURE, BUT
THINK THIS IS AN OUTLIER COMPARED TO THE REST OF THE MODELS. THE MAIN
IMPLICATIONS FROM THIS WOULD BE AREAS OF STRATUS AND SLIGHTLY WARMER
MINIMUMS UNDER THE CLOUD DECK. WILL HOLD OFF FOR NOW ON THIS SOLUTION.
TOMORROW:
FLAT 500 HPA RIDGING IS EXPECTED ACROSS THE ROCKIES AND HIGH PLAINS
TOMORROW. THIS WILL LEAD TO WESTERLY FLOW ALOFT AND DOWNSLOPE SOUTHWESTERLY
SURFACE TO 600 HPA WINDS. THE ATMOSPHERE BECOMES DEEPLY MIXED TO ABOUT
650 HPA WHICH SUPPORTS WARMER MAXIMUM TEMPERATURES FOR TOMORROW VIA
ADIABATIC COMPRESSIONAL WARMING. THE WIND PROFILE WITHIN THIS LAYER
IS NOT PARTICULARLY STRONG, BUT I DO THINK BREEZY CONDITIONS ARE EXPECTED
AS MIXING AND RESULTANT MOMENTUM TRANSFER DEVELOPS/CONTINUES TOMORROW.
HIGHS WILL BE IN THE 70S DEG F RANGE. NO PRECIPITATION IS EXPECTED AS
SUBSIDENCE IN THE WAKE OF THE TROUGH PREVAILS. A LEE SURFACE TROUGH
ACROSS EASTERN COLORADO WILL CONTINUE AS WELL WITH THE AFOREMENTIONED
PERPENDICULAR FLOW TO THE ROCKIES.
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 328 AM CDT MON APR 16 2012
THE 00Z RUNS OF THE MEDIUM RANGE MODELS CONTINUE TO BE IN FAIRLY
GOOD AGREEMENT WITH EACH OTHER AND ARE FAIRLY CONSISTENT WITH
PREVIOUS RUNS WITH REGARD TO THE UPPER FLOW PATTERN THIS WEEK. THE
ZONAL PATTERN WILL RESULT IN A WARMING TREND THROUGH MIDWEEK.
A SHORTWAVE TROUGH MOVING OUT OF THE PACIFIC NORTHWEST ON WEDNESDAY
WILL UNDERGO AMPLIFICATION AS IT MOVES OUT OVER THE PLAINS ON
THURSDAY. THE MODELS ALL SHOW A COLD FRONT PUSHING THROUGH SOUTHWEST
KANSAS ON THURSDAY. THE MODELS DEVELOP SOME LIGHT QPF WITH THE
WAVE AND FRONT. THERE IS SOME LIMITED INSTABILITY BUT MODEL
SOUNDINGS ARE NOT OVERLY IMPRESSIVE SO WILL KEEP A SLIGHT CHANCE
FOR SHOWERS AND ISOLATED THUNDERSTORMS ACROSS SOUTHWEST KANSAS
THURSDAY INTO THURSDAY EVENING.
THE MODELS SHOW A SECONDARY SHORTWAVE TROUGH DIVING OUT OF THE
NORTHERN HIGH PLAINS ACROSS KANSAS ON FRIDAY AND SHOW SOME LIGHT
PRECIPITATION WITH THIS WAVE AS WELL. NOT OVERLY CONFIDENT WE WILL
SEE ANYTHING DEVELOP IN THE NORTHWEST FLOW PATTERN BUT WILL LEAVE
IT IN FOR NOW.
DRY WEATHER WILL ROUND OUT THE WEEKEND INTO EARLY NEXT WEEK AS A
HIGH AMPLITUDE RIDGE MOVES INTO THE CENTRAL CONUS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1230 PM CDT MON APR 16 2012
MAIN CONCERN FOR THE 18Z TAFS IS THE POSSIBILITY OF SHOWERS THIS AFTERNOON.
CIGS WILL REMAIN PRIMARILY VFR THROUGH THE PERIOD. DID INSERT VCSH FOR
THE TERMINALS THIS AFTERNOON. IF IT DOESN`T PRECIPITATE THEN AT LEAST
AN INCREASE OF CUMULUS IS EXPECTED LATER AS A MINOR UL SHORTWAVE TROUGH
SKIRTS ACROSS THE REGION.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 44 77 48 78 / 30 0 0 0
GCK 41 75 45 77 / 30 0 0 0
EHA 38 77 46 81 / 20 0 0 0
LBL 41 78 47 81 / 30 0 0 0
HYS 42 74 48 75 / 30 0 10 0
P28 46 74 52 79 / 20 0 0 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...SUGDEN
SHORT TERM...SUGDEN
LONG TERM...GERARD
AVIATION...SUGDEN
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
210 PM EDT MON APR 16 2012
.SYNOPSIS...
ISSUED AT 556 AM EDT MON APR 16 2012
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW POTENT SHRTWV/H5
CLOSED LO LIFTING NEWD INTO MN ON NW FLANK OF SHARP RDG OVER THE SE
CONUS...WITH OCCLUDED SFC LO NOT FAR FM MPX AT 03Z. WARM FNT
EXTENDING E FM THIS FEATURE CROSSES NRN WI TO JUST S OF MNM AND
SEPARATES SFC T/TD ARND 70/60 FM T/TD IN THE 40S AND 50S OVER UPR
MI. SLOW WARMING HAS GRADUALLY ERODED SOME LOCALLY DENSE FOG THAT
WAS PRESENT EARLIER OVER THE CWA. DRY SLOTTING ALF E OF THE SHRTWV
HAS INVADED THE CWA/MUCH OF WI...WITH SOME SHRA/TS OVER LK SUP JUST
N OF THE H85 WARM FNT WHERE H7-6 FGEN IS SHARPEST. SOME ISOLD SHRA
ARE LOCATED OVER WI S OF THE WARM FNT. HEAVIER/MORE WIDESPREAD
SHRA/TS ARE PRESENT OVER ERN WI/LK MI WITHIN THE WARM CONVEYOR BELT
MSTR TO THE E OF THE DRY SLOT THAT WL ALSO MISS UPR MI TO THE E. TO
THE NW...WELL DEFINED CCB IS PRESENT FM NRN MN EXTENDING INTO THE
ERN DAKOTAS ON THE CYC SIDE OF H5 LO TRACK. A BAND OF SHRA/SOME TS
IS PRESENT EXTENDING FM NW WI TO FAR SE MN ON THE WRN EDGE OF DRY
SLOT/IN ADVANCE OF APRCHG UPR LO...WHERE SPC MESOANALYSIS INDICATES
MUCAPE ARND 500 J/KG TO THE S OF SFC WARM FNT. DESPITE SOME SHARP
H7-3 QVECTOR CNVGC/DIFFLUENT UPR FLOW IN EXIT REGION OF SUPPORTING
120KT H3 JET MAX/HGT FALLS AHEAD OF THIS FEATURE/SFC-6KM BULK SHEAR
UP TO 70 KTS...THE TS HAVE NOT INTENSIFIED AS THE LINE OF SHRA MOVES
E INTO WI EVEN THOUGH THERE HAVE BEEN SOME WIND GUSTS UP TO 40 KTS
OBSVD WHERE THE CONVECTION IS SFC BASED IN THE WARM SECTOR. MODERATE
RA IS FALLING IN THE COLDER AIR OVER MUCH OF NRN MN UNDER THE
SHARPLY NNE CYC FLOW TO THE N AND NW OF THE SFC LO...WITH N WIND
GUSTS 30-40 KTS. SN HAS MIXED IN WITH THE PCPN OVER NRN MN AS THESE
STRONG WINDS HAVE DRAWN COLDER AIR TO THE S. THE 00Z H85 WIND AT
ABERDEEN SDAKOTA WAS 75 KTS. 02Z NE WIND GUSTS DOWN THE W END OF LK
SUP REACHED 44 MPH AT ASX IN NW WI. NO SN IS FALLING UNDER THIS AREA
AS OF MIDNGT...BUT MUCH COLDER AIR LURKS JUST TO THE N...WITH 00Z
H85 TEMP -11C AT YPL.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 556 AM EDT MON APR 16 2012
MAIN FCST CONCERNS FOR TODAY INTO TNGT ARE POPS/PTYPE/POTENTIAL FOR
STRONG WINDS ASSOCIATED WITH CCB THAT WL SHIFT ACRS UPR MI AS THE
SHRTWV/SFC LO MOVES TO THE E.
TODAY...SFC LO IS PROGGED TO MOVE TO SE LK SUP/ERN UPR MI BY 18Z
BEFORE CONTINUING INTO QUEBEC BY 00Z. SINCE THE SHRTWV WL BE MOVING
INTO A ZONE OF UPR CONFLUENCE BTWN THE BASE OF UPR TROF CENTERED
NEAR HUDSON BAY AND UPR RDG IN THE SE CONUS...THE SHRTWV/SFC LO ARE
EXPECTED TO WEAKEN...ESPECIALLY THIS AFTN. EVEN SO...TIGHT PRES
GRADIENT/SHARP NLY FLOW ON THE WRN FLANK OF THE DEPARTING LO ARE
FCST TO ADVECT MUCH COLDER AIR LURKING TO THE N INTO THE UPR LKS.
EXPECT INCRSG POPS OVER THE W BY SUNRISE TO SPREAD EWD WITH THE
DEEPER MSTR UNDER THE CCB. FCST SDNGS STILL SHOW SOME SHARP COOLING
BLO ELEVATED WARM LYR...SO WL RETAIN MENTION OF SLEET IN THE
TRANSITION BTWN ALL RA AND MORE SN ONCE DEEPER COLD AIR ARRIVES OVER
THE W BY AFTN. BUT STRONG CAD/WEAKENING UPR DVGC AS JET CORE SHIFTS
TO THE NE WL TEND TO CAUSE THE CCB TO DECAY A BIT AS LARGER SCALE
QVECTOR DVGC DVLPS OVER THE CCB. ALTHOUGH FCST H85 TEMPS FALLING AS
LO AS -13C TO -15C BY 00Z COULD ADD SOME LK ENHANCED COMPONENT INTO
THE PCPN FIELD...WEAKENING DYNAMICS SHOULD LIMIT THIS POTENTIAL WITH
THE COLDEST AIR ARRIVING ONLY AFT 18Z ONCE LARGER SCALE QVECTOR DVGC
DOMINATED BY THE CAD IS IN PLACE. SO EXPECT SN ACCUMS TO BE SUB
ADVY. THE ARRIVAL OF THE COLDER AIR WL SHARPEN LLVL INSTABILITY AND
AID MIXING OF H925 WINDS UP TO 35 TO 45 KTS. ALTHOUGH THE APRCH FM
THE WSW OF THE SHARP PRES RISE CENTER WL RESULT IN ISALLOBARIC WIND
COMPONENT AT A RIGHT ANGLE OR EVEN OPPOSING THE GRADIENT FLOW AND
THE LO WL BE WEAKENING WITH TIME... THE MAGNITUDE OF THE GRADIENT
WIND IN CONCERT WITH FAVORABLE MIXING UNDER THE INCOMING THERMAL
TROF JUSTIFY ISSUANCE OF HI WIND ADVYS FOR EXPOSED LOCATIONS NEAR
THE LK SUP SHORE.
TNGT...AS HI PRES BLDS INTO THE WRN CWA OVERNGT...THE PRES GRADIENT
WL DIMINISH QUICKLY FOLLOWING PASSAGE OF PRES RISE CENTER TO THE E
AFT 00Z. SO EXPECT GUSTY WINDS TO DIMINISH QUICKLY THIS EVNG INTO
THE OVERNGT. BUMPED POPS UP TO LIKELY IN AREAS E OF MQT WITH H85
THERMAL TROF/TEMPS AS LO AS -13C TO -15C CONDUCIVE FOR SOME LES IN
MOIST CYC NW FLOW. SUBSIDENCE DROPPING INVRN AOB 3K FT/RISING H85
TEMPS/WEAKENING CYC FLOW OVERNGT WL CAUSE ANY SHSN TO DIMINISH
STEADILY AFT MIDNGT. CONSIDERING THE CHILL OF THE INCOMING
AIRMASS...PWAT FALLING BLO 0.25 INCH...AND THE PROSPECT OF CLRG OVER
THE INTERIOR W AS HI PRES BLDS OVHD...TENDED TO GO LOWER THAN
PREVIOUS FCST FOR MIN TEMPS IN THAT AREA.
TUE...HUDSON BAY HI PRES/DRY AIRMASS WL DOMINATE UPR MI...BRINGING
RELATIVELY DRY AND TRANQUIL WX. ALTHOUGH THERE WL BE SOME LINGERING
SC OVER MAINLY THE E HALF IN THE MRNG WITH LINGERING LIGHTER CYC
FLOW/LLVL MSTR/THERMAL TROF UNDER SUBSIDENCE INVRN...THIS CLD SHOULD
DISSOLVE BY AFTN WITH ARRIVAL OF SFC HI PRES RDG/ACYC FLOW AND
DAYTIME HEATING...GIVING WAY TO JUST SOME DIURNAL CU. MIXING TO H85
ON GFS FCST SDNGS WOULD YIELD HI TEMPS RANGING FM ARND 40 AT ERY TO
50 NEAR THE WI BORDER...BUT THE DAY WL BE COOLER NEAR THE MODIFYING
INFLUENCE OF THE LKS AS WEAK PRES GRADIENT IN THE AFTN WL ALLOW FOR
LK BREEZE DEVELOPMENT.
.LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY)
ISSUED AT 556 AM EDT MON APR 16 2012
MUCH OF LONGER RANGE PORTION OF FCST IS DOMINATED BY NEGATIVE UPPER
AIR ANAMOLIES STATIONED OVER NORTHEAST PACIFIC OCEAN/GULF OF ALASKA
AND OVR HUDSON BAY INTO NUNAVUT CANADA. ZONAL FLOW FCST TO IMPACT
CONUS MUCH OF THE WEEK AND INTO NEXT WEEKEND AS WELL.
ATTM ONLY ONE SYSTEM IS SURE THING TO IMPACT THE AREA IN THE LONGER
TERM. THIS IS STILL OPEN TO CHANGE DEPENDING ON TRACK OF LATE WEEK
SYSTEM.
SHORTWAVE ON SOUTHERN EDGE OF TROUGH OVR NORTHEAST PACIFIC/GULF OF
ALASKA FCST TO SLIDE ACROSS ROCKIES INTO NORTHERN PLAINS ON TUESDAY
NIGHT AND PUSH ACROSS UPPER GREAT LAKES ON WEDNESDAY. SW WINDS AHEAD
OF SFC-H85 TROUGH BRINGS MUCH WARMER/MOIST AIR INTO UPR LAKES IN WAKE
OF THE EARLY WEEK CHILL. JET STREAKS SLIDING ACROSS THE NORTHERN
PLAINS AND OVR ONTARIO SHOULD HELP SYSTEM STAY FAIRLY ORGANIZED AS
IT CROSSES CWA ON WEDNESDAY. APPEARS THAT SYSTEM WILL BE COMPACT AS
IT MOVES THROUGH...LEADING TO A FAIRLY STRONG WIND FIELD IN THE
VCNTY. HAVE INCREASED WINDS ESPECIALLY IN THE WAKE OF THE LOW LATE
WEDNESDAY INTO WEDNESDAY NIGHT NEAR LAKE SUPERIOR.
PTYPE MAY BE ISSUE INITIALLY WITH SNOW OR EVEN FREEZING RAIN
POSSIBLE INTERIOR CNTRL /10Z-12Z ON WEDNESDAY/ AS SWATH OF
PRECIPITATION ARRIVES OVER PERSISTENT SHALLOW COLD AIR. ANY WINTRY
PRECIP SHOULD BE BRIEF THOUGH AS STRONG WARM AIR ADVECTION SFC-H85
QUICKLY BECOMES DOMINANT. ADDED TSRA FOR WEDNESDAY AS WELL DUE TO
STEEP H7-H5 LAPSE RATES AOA 8C/KM. PRETTY DYNAMIC SYSTEM LOOKS TO
AFFECT THE AREA. GIVEN CONVECTIVE POTENTIAL MAY SEE RAIN TOTALS OVR
0.25 INCH IN SOME AREAS. STILL SOME POTENTIAL FOR SNOW AS SYSTEM
EXITS ON WEDNESDAY NIGHT. 850MB/925MB TEMPS AS LOW AS -10C/-6C STILL
LEAVES POTENTIAL FOR BRIEF LAKE ENHANCED SNOW OVR HIGHER TERRAIN OF
WEST CWA IF ENOUGH MOISTURE REMAINS IN PLACE. JUST LOW CHANCE POPS
FOR NOW.
IN THE EXTENDED...FRIDAY SYSTEM IS BACK ON FOR AT LEAST THE
SOUTHEAST QUARTER OF THE CWA...AT LEAST ACCORDING TO ECMWF AND
CANADIAN. ECMWF HAS SHOWN THIS OFF AND ON FOR LAST FEW DAYS AND
LATEST GFS HAS TRENDED NORTH...THOUGH IS STILL MAINLY SOUTH OF CWA
WITH ITS AXIS OF MAX QPF. SINCE SFC LOW IS STILL FCST TO PASS MAINLY
OVR CNTRL GREAT LAKES EVEN ON THE ECMWF...PCPN IF IT OCCURS WOULD
LIKELY STAY MAINLY IN FORM OF SNOW. ECMWF WOULD POINT TO SEVERAL
INCHES OF ACCUMULATION OVR SE CWA JUST NORTH OF H85-H7 LOW TRACK.
SYSTEM IS STILL NEAR THE ALLUTIANS IN THE PACIFIC SO EXPECT MORE
JUMPING AROUND ON THE POSITION OF THE LOW YET THIS WEEK. SOMETHING
TO DEFINITELY KEEP AN EYE ON THOUGH.
BEYOND FRIDAY APPEARS DRY WEATHER IS IN STORE FOR NEXT WEEKEND. WILL
NOT BE ESPECIALLY WARM THOUGH AS LARGER SCALE TROUGH RESIDES OVR
MUCH OF EASTERN CANADA AND EASTERN CONUS. SFC-H85 RIDGE WILL BE
OVERHEAD LEADING TO LIGHT WINDS/LK BREEZES. BEST CHANCE FOR DAYTIME
TEMPS AT LEAST NEAR NORMAL WILL BE WELL INLAND FM THE LAKES TOWARD
WISCONSIN BORDER. COULD ALSO BE CHILLY NIGHTS AS WELL...WITH TEMPS
POSSIBLY IN THE TEENS AND 20S. EXPECT RELATIVE HUMIDITIES TO BE ON
THE LOW SIDE FOR THE WEEKEND AS WELL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 209 PM EDT MON APR 16 2012
FROZEN PRECIPITATION IS NOW FALLING AT ALL THREE SITES AS COLD AIR
SURGES INTO THE AREA BEHIND A DEPARTING LOW PRESSURE. EXPECT -PLSN
AT SAW TO TRANSITION COMPLETELY TO -SN BY 19Z. OTHERWISE...BACK END
OF THE MAIN -SN SHIELD WILL PASS THROUGH IWD AND CMX THIS AFTERNOON
TO GIVE WAY TO -SHSN AND ALLOW BOTH SITES TO IMPROVE TO IFR
CONDITIONS. NOT TOO CONCERNED WITH VIS AS UPSTREAM AIR IS RELATIVELY
DRY...THOUGH THE HEAVIEST SNOW SHOWERS COULD TEMPORARILY DROP VIS
BELOW 1SM. STRONG WINDS QUICKLY SUBSIDE FROM WEST TO EAST THIS
EVENING AS A WEAK RIDGE BUILDS OVER LAKE SUPERIOR LATE TONIGHT.
EXPECT IFR CIGS TO HOLD THROUGHOUT THE NIGHT AS LAKE MODIFIED AIR
KEEPS A LITTLE MOISTURE AROUND...EXPECT AT IWD WHERE SOME DRYING
COULD TAKE PLACE LATE TONIGHT AND SCATTER OUT THE CLOUDS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 556 AM EDT MON APR 16 2012
CONSIDERING A NUMBER OF OBS SHOWING WIND GUSTS UP TO 50 KTS OVER THE
W HALF WHERE TERRAIN ENHANCES THE PREVAILING NE FLOW EARLY THIS
MRNG...OPTED TO ISSUE STORM WARNINGS FOR THE 3 WESTERN ZONES OF LAKE
SUPERIOR. AS THE FLOW BACKS TO N...EXPECT THE WINDS TO SUBSIDE A BIT
WITH JUST N GALES THRU THE AFTN AS THE ARRIVAL OF MUCH COLDER
ENHANCES MIXING OF HIER MOMENTUM TO THE LAKE SURFACE. EVEN THESE
WINDS WILL TEND TO DIMINISH OVER THE FAR W LATER IN THE DAY WITH
APPROACH OF HI PRES RIDGE. LINGERING GALES WILL END OVER THE REST OF
THE LAKE AS THE HI PRES RIDGE/WEAKER PRES GRADIENT DOMINATES THE
LAKE.
NEXT LOW PRES SYSTEM FCST TO MOVE THRU THE UPPER LAKES WED IS NOW
LOOKING STRONGER. EXPECT SOUTHERLY WINDS TO 30 KTS WEDNESDAY MORNING
TO SHIFT TO THE WEST AND INCREASE TO GALES ESPECIALLY OVER THE EAST
HALF OF THE LAKE BY LATER WEDNESDAY AFTN AND INTO THE EARLY EVENING.
WINDS DIMINISH BLO 25 KTS LATER WEDNESDAY NIGHT INTO THURSDAY AS
HIGH PRESSURE MOVES BACK OVR THE UPR LAKES REGION. SFC LOW PASSING
BY ACROSS THE CNTRL GREAT LAKES THURSDAY NIGHT INTO FRIDAY COULD
RESULT IN NORTHEAST WINDS 25-30 KTS OVR SOUTHERN PORTIONS OF LK
SUPERIOR.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WIND ADVISORY UNTIL 4 PM EDT THIS AFTERNOON FOR MIZ002-003.
WIND ADVISORY UNTIL 8 PM EDT THIS EVENING FOR MIZ001-005.
WIND ADVISORY UNTIL 11 PM EDT THIS EVENING FOR MIZ006-007.
LAKE SUPERIOR...
GALE WARNING UNTIL 2 AM EDT TUESDAY FOR LSZ251-267.
GALE WARNING UNTIL 2 AM EDT TUESDAY FOR LSZ249-250-266.
GALE WARNING UNTIL 8 PM EDT THIS EVENING FOR LSZ242>245-248-
263>265.
LAKE MICHIGAN...
GALE WARNING UNTIL 11 PM EDT THIS EVENING FOR LMZ221-248-250.
&&
$$
SYNOPSIS...KC
SHORT TERM...KC
LONG TERM...JLA
AVIATION...TK
MARINE...KC/JLA
AREA FORECAST DISCUSSION...UPDATED FOR 18Z TAFS
NWS TWIN CITIES/CHANHASSEN MN
100 PM CDT MON APR 16 2012
.DISCUSSION...ISSUED 352 AM CDT
MID/UPPER LEVEL CIRCULATION WILL CONTINUE TO CAUSE LIGHT PRECIP
OVER EASTERN AREAS THIS MORNING WITH LATEST RUC PICKING UP ON A
SSW-NNE BAND OF FGEN..PRIMARILY OVER EAST CENTRAL MN BUT THEN
WEAKENING WITH TIME OVER WEST CENTRAL WI. IT DOES LOOK LIKE LOW
LEVEL THICKNESSES WILL BE COLD ENOUGH TO SUPPORT SOME SNOW OR A
LEAST A RAIN AND SNOW MIX FARTHER SOUTHEAST TOWARD STC/MSP. STILL
AT WIND ADVSY CRITERIA OVER WEST CENTRAL MN AND STRONGER WINDS
WILL LIKELY LAST THROUGH THE MORNING IN THE EASTERN AREAS OF
CURRENT ADVSY. BAND OF 40 KNOT WINDS AT AROUND 925 MB OVER
FAVORED WINDY AREAS SHOWING UP ON THE RUC AND SOME OF THE WIND
GUST PRODUCTS MATCHING AS WELL. IT MIGHT BE CLOSE FOR SOME OF THE
STRONG WINDS FARTHER EAST TOWARD MSP BUT NOT LASTING REAL LONG.
CLEARING BUILDING IN TONIGHT AND THE CURRENT MENTION OF FROST LOOKS
OK UNDER TH RIDGE. STILL RATHER ACTIVE FOR THE REST OF THE WEEK WIT
A COUPLE OF DECENT WAVE IN THE STRONG WESTERLY FLOW. THE SYSTEM
FORECAST TO MOVE INTO THE AREA ON TUESDAY NIGHT AND WEDNESDAY DOES
HAVE SOME INSTABILITY ALONG WITH A WELL DEFINED DIFLUENT FLOW
PATTERN AND PV. HAVE RAISED POPS A BIT MORE INTO THE LIKELY
CATEGORY AND AT LEAST ISOLATED THUNDER LOOKS GOOD PRIMARILY OVER
SOUTH CENTRAL MINNESOTA. THE NEXT SYSTEM IS SIMILAR BUT
INSTABILITY MUCH FARTHER SOUTH...AND MORE OF AN ISENTROPIC LIFT
BAND OF FORCING AFFECTING MAINLY SOUTHERN MN. LOOKS LIKE A QUIET
PERIOD FOR LATER IN THE WEEK AND THE WEEKEND WITH BOTH GFS AND
ECMWF SHOWING AN UPPER RIDGE DEVELOPING IN THE CENTRAL CONUS OR
JUST SLIGHTLY WEST.
&&
.AVIATION.../18Z TAF ISSUANCE/
WIDESPREAD MVFR CIGS ACROSS AREA...BUT SUBSIDENCE IN WAKE OF MASSIVE
LOW PRESSUE LIFTING NE OF AREA HAS SCOURED OUT BINOVC ACROSS MUCH OF
W MN. EXPECT TO SEE SOME THINNING OF CLOUDS FARTHER EAST DURING THE
AFTN WITH BASES SLOWLY LIFTING INTO HIGH END MVFR CIGS. EXPECT A
CONTINUED DECREASE IN THESE CLDS ACROSS AREA THIS EVENING AND INTO
THE OVERNIGHT WITH MVFR CIGS IN THE DKTS STAYING MAINLY WEST OF
TAFS. WITH WDSRPD RAINS OVER THE WEEKEND...THERE IS SOME THREAT FOR
FOG IN EASTERN TAF AREAS AS HIGH PRESSURE MOVES ACROSS OVERNITE.
PUT A PRD OF MVFR FOG AT STC FROM AROUND 05-09Z WITH PRESSURE
GRADIENT PICKING UP LATE TONGIHT. A BETTER CHC OF FOG AT EAU AND
PERHAPS RNH LAT TONIGHT. A COUPLE OF WEAK VORTS UPSTREAM IN THE
DKTS WITH ONE NEAR DVL AND THE OTHER W OF PIR. THEY MAY BRING A FEW
MID CLDS INTO W MN AS THEY DIVE SE. GUSTY NW WINDS WILL CONTINUE TO
DECREASE FROM WEST TO EAST ACROSS AREA AS DEEP SFC LOW LIFTS RPDLY
NE OF AREA NAND HIGH PRESSURE BUILDS ACROSS AREA.
KMSP...MVFR CIGS WILL CONTINUE THRU AFTN WITH BASES VERY SLOWLY
RISING AND BECOMING VFR AFT 01Z. NW WINDS TO SLOWLY DMNSH DRNG THE
AFTN WITH SPEEDS LESS THAN 10 KTS BY 01Z AND THEN LGT WINDS DRNG THE
OVERNITE...BECOMING SE ON TUESDAY MRNG.
OUTLOOK TUESDAY...VFR.
TUE NITE INTO WED NITE...VFR TO PSBL MVFR WITH -SHRA.
&&
.MPX WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
JPR/BAP
AREA FORECAST DISCUSSION
NWS RALEIGH NC
146 PM EDT MON APR 16 2012
.SYNOPSIS...
A COLD FRONT WILL CONTINUE TO MOVE SLOWLY EAST...CROSSING THE
WESTERN HALF OF NORTH CAROLINA OVERNIGHT. THE FRONT THEN REMAINS
NEARLY STATIONARY TOWARD THE COAST TUESDAY NIGHT INTO WEDNESDAY.
WEAK HIGH PRESSURE BUILDS INTO THE REGION BEHIND THE COLD FRONT
THURSDAY.
&&
.NEAR TERM /TODAY/...
AS OF 1020 AM MONDAY...
THE LATEST SURFACE ANALYSIS SHOWED HIGH PRESSURE JUST OFFSHORE
NOSING WEST THROUGH CENTRAL NORTH CAROLINA...WITH MSAS INDICATIVE OF
SURFACE-BASED DIVERGENCE OVER THE AREA. ON UPPER-AIR ANALYSES...
850MB MOISTURE WAS BEGINNING TO MOVE THROUGH THE WESTERN THIRD OF
THE STATE...WITH 850MB DEW POINTS JUST BELOW 10C. HOWEVER...THE MID-
AND UPPER-LEVEL RIDGE AXES WERE FIRMLY IN PLACE OVER THE FAR EASTERN
PART OF THE STATE AND ALONG THE COAST...WITH CONSIDERABLE DRY AIR
NOTED AT 700MB AND VERY DRY AIR ALSO NOTED IN THE MID-LEVELS ON
WATER VAPOR IMAGERY. THE LATEST NAM BUFR SOUNDINGS REMAINED STABLE
DURING THE DAY...AS THE CAP AT AND JUST ABOVE 700MB HOLDS EVEN AS
850MB THETA-E VALUES INCREASE OVER THE WESTERN PIEDMONT AND
PRECIPITABLE WATER VALUES RISE TO NEARLY 1.25 INCHES. THE RUC IS NOT
AS UNSTABLE AS THE NAM THIS AFTERNOON...LIFTED INDICES OF 0C TO -1C
ON THE FORMER VERSUS -2C TO -3C ON THE LATTER...AND EVEN THE NAM IS
PREDOMINANTLY SUBSIDENT DURING THE AFTERNOON. WILL CONTINUE TO KEEP
THE FORECAST DRY.
MORNING KGSO AND AMDAR SOUNDINGS SHOWED WINDS ONCE AGAIN JUST OFF
THE SURFACE A LITTLE HIGHER THAN WAS FORECAST BY SUNDAY GUIDANCE...
CLOSE TO 40KT. AS MIXING OCCURS THESE WINDS SHOULD DIMINISH...AND
MIXING SHOULD NOT TAKE PLACE FAST ENOUGH TO RESULT IN GUSTS BEYOND
THE 20S KTS. BUFR SOUNDINGS SHOW GUST POTENTIAL IS HIGHEST TOWARD
KGSO...WHERE SOME GUSTS APPROACHING 25KT ARE POSSIBLE. 1000-850MB
THICKNESSES SUPPORT HIGHS AS CURRENTLY FORECAST...SOLIDLY 81 TO 86
WITH MAYBE A LOCATION OR TWO APPROACHING THE UPPER 80S. SURFACE DEW
POINTS WILL BE SIMILAR TO SUNDAY...AND WITH THE WARMER TEMPERATURES
RELATIVE HUMIDITIES WILL BE A LITTLE LOWER...BOTTOMING OUT AT OR
JUST BELOW 35 PERCENT. WITH THE DRY FUELS IN PLACE...AN INCREASED
FIRE DANGER CONTINUES TO BE NOTED FOR THE AFTERNOON...INTO EARLY
EVENING.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY/...
AS OF 345 AM MONDAY...
OVERVIEW:
SHORTWAVE ENERGY DIGGING SOUTHEAST THROUGH THE 4-CORNERS REGION AT
06Z THIS MORNING WILL ROUND THE BASE OF THE LONGWAVE TROUGH PRESENT
OVER THE CENTRAL CONUS TODAY...THEN PROGRESS EASTWARD INTO THE DEEP
SOUTH DURING THE DAY TUESDAY AS A MORE ZONAL PATTERN DEVELOPS OVER
THE LOWER 48 IN THE WAKE OF THE DEAMPLIFYING UPPER LEVEL LOW
PROGRESSING TOWARD THE CANADIAN MARITIMES. THE FRONT WILL BECOME
INCREASINGLY W-E ORIENTED OVER THE AREA TONIGHT AS THE PARENT LOW
WEAKENS AND TRACKS WELL NORTHEAST INTO CANADA. THE FRONT IS EXPECTED
TO STALL OUT NEAR THE SANDHILLS/COASTAL PLAIN PORTION OF THE NC/SC
BORDER DURING THE DAY TUE.
TONIGHT:
MID-LEVEL LAPSE RATES WILL WEAKEN FROM WEST-EAST OVERNIGHT AS THE
UPPER LEVEL RIDGE SHIFTS OFFSHORE...HOWEVER...INCREASING BOUNDARY
LAYER MOISTURE IN ASSOC/W THE FRONTAL ZONE PROGRESSING INTO THE AREA
MAY ALLOW FOR A VERY MARGINAL AMOUNT OF MUCAPE...ON THE ORDER OF 250
J/KG. W/REGARD TO FORCING...VERY WEAK/SHALLOW LOW LEVEL CONVERGENCE
WILL BE PRESENT OVER THE AREA AS THE FRONT SLOWS DOWN AND BECOMES
INCREASINGLY W-E ORIENTED OVER THE AREA. ALTHOUGH A WEAK DISTURBANCE
IN SOUTHWEST FLOW ALOFT CANNOT BE RULED OUT...THE AFOREMENTIONED
SHORTWAVE IS EXPECTED TO PROGRESS NO FURTHER THAN EASTERN TX BY 12Z
TUE...AND THE BEST CHANCE FOR SMALL AMPLITUDE DISTURBANCES OR
CONVECTIVE RELATED FEATURES IS EXPECTED TO BE UPSTREAM IN THE DEEP
SOUTH. IF AN UPPER LEVEL DISTURBANCE PROGRESSES INTO THE AREA VIA SW
FLOW ALOFT IN THE PRESENCE OF MARGINAL MUCAPE AND WEAK/SHALLOW
LOW-LEVEL CONVERGENCE A FEW ISOLD SHOWERS COULD NOT BE RULED OUT IN
THE WEST/SW PIEDMONT...THOUGH THAT SCENARIO APPEARS UNLIKELY. WITH
THE ABOVE IN MIND...WILL KEEP THE FCST DRY. GIVEN INCREASING
BOUNDARY LAYER MOISTURE AND LOW/MID LEVEL CLOUD COVER...EXPECT LOWS
IN THE LOWER/MID 60S.
TUESDAY:
COMPLEX FORECAST. THE AFOREMENTIONED SHORTWAVE WILL PROGRESS EAST
INTO THE DEEP SOUTH (MS/AL) BY TUE AFT/EVE...WITH BROAD H5 HEIGHT
FALLS (40 METERS 12-00Z) DOWNSTREAM OVER THE CAROLINAS ALONG WITH AN
INCREASING POTENTIAL FOR SMALL AMPLITUDE DISTURBANCES OR CONVECTIVE
RELATED FEATURES PROGRESSING INTO THE AREA VIA SW FLOW ALOFT.
HOWEVER...THE BEST UPPER LEVEL FORCING ASSOC/W THE SHORTWAVE WILL
REMAIN WELL UPSTREAM OF THE AREA (MS/AL)...AND THE TIMING/LOCATION
OF ANY SMALLER AMPLITUDE DISTURBANCES ARE VERY MUCH IN QUESTION AT
THIS TIME...AND MAY ULTIMATELY DEPEND ON THE EVOLUTION OF DEEP
CONVECTION OVER THE LOWER MS RIVER VALLEY LATE TONIGHT AND TUE
MORNING. COMPLICATING MATTERS FURTHER...MODEL GUIDANCE VARIES ON THE
POSITION OF THE STALLED FRONTAL ZONE ON TUE...RANGING FROM DIRECTLY
OVER CENTRAL NC (00Z ECMWF)...TO JUST S/SE OF THE AREA (00Z GFS)...
TO PORTIONS OF THE SANDHILLS/SE COASTAL PLAIN (00Z NAM). THE
LOCATION OF THE SFC FRONT WILL LARGELY DETERMINE THE LOCATION/EXTENT
OF DIURNAL DESTABILIZATION TUE AFTERNOON. REGARDLESS...THE RELATIVE
BEST INSTABILITY IS EXPECTED TO BE PRESENT IN FAR S/SE PORTIONS OF
THE AREA WHERE 500-1000 J/KG OF MLCAPE IS PROGGED. GIVEN
CONSIDERABLE UNCERTAINTY WITH THE TIMING/LOCATION OF UPPER LEVEL
FORCING AND THE SURFACE FRONT AS MENTIONED ABOVE...WILL LEAVE THE
PREVIOUS FCST MORE OR LESS INTACT...INDICATING CHANCES FOR
SHOWERS/STORMS RANGING FROM 20-50%...LOWEST IN THE NE COASTAL PLAIN
AND HIGHEST NEAR THE SC BORDER/SE COASTAL PLAIN. HIGH TEMPS ARE
EQUALLY CHALLENGING ON TUE...WITH A BUST POTENTIAL OF 3-7F DEPENDING
ON THE LOCATION OF FRONT AND TIMING/LOCATION OF ANY CONVECTION THAT
MAY BE PRESENT. A BLEND OF MODEL GUIDANCE APPEARS REASONABLE...WITH
HIGHS RANGING FROM THE LOWER 80S SOUTH/SE TO MID 70S N/NW.
SEVERE THREAT:
SPC HAS HIGHLIGHTED A SLIGHT RISK FOR SEVERE STORMS OVER GA/SC AND
FAR SOUTHERN PORTIONS OF CENTRAL NC...PRIMARILY ADJACENT TO THE SC
BORDER. CONSIDERABLE UNCERTAINTY PERSISTS WITH REGARD TO THE
LOCATION/COVERAGE OF CONVECTION TUE AFTERNOON AS MENTIONED ABOVE...
THOUGH THE MOST LIKELY LOCATION IS IN THE FAR SW PIEDMONT...
SANDHILLS AND SE COASTAL PLAIN WHERE 500-1000 J/KG MLCAPE IS
PROGGED. THE HEIGHT GRADIENT ALOFT WILL TIGHTEN OVER THE CAROLINAS
ON TUE AS THE SHORTWAVE PROGRESSES INTO THE DEEP SOUTH...AND 0-6 KM
BULK SHEAR VALUES ARE PROGGED TO BE AT LEAST IN THE 30-35 KT RANGE
IN SOUTHERN PORTIONS OF THE AREA (HIGHER NORTH)...WITH LARGER
AMOUNTS (40-45 KT) POSSIBLE. AS A RESULT...DEEP LAYER SHEAR WILL
CERTAINLY BE SUFFICIENT FOR MULTICELLULAR ORGANIZATION...AND
POSSIBLY SUPERCELLULAR. GIVEN VERY WEAK LOW-LEVEL SHEAR...EVEN IN
VICINITY OF THE STALLED FRONT...THE PRIMARY SEVERE THREAT WILL
LIKELY BE CONFINED TO HAIL/WIND. AN ISOLD BRIEF/WEAK TORNADO COULD
NOT BE ENTIRELY RULED OUT...THOUGH ONLY IN ASSOCIATION WITH
STORM-SCALE INTERACTIONS. -VINCENT
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
AS OF 325 AM MONDAY...
COOLER AND DAMP PERIOD MID WEEK... POTENTIAL FOR HEAVY RAIN NEXT
WEEKEND...
MODELS CONTINUE TO POINT TOWARD A COOL DAMP PERIOD TUESDAY NIGHT
THROUGH WEDNESDAY NIGHT... FOLLOWED BY A GRADUAL DRYING AND WARMING
THURSDAY AND FRIDAY. IT APPEARS THAT A FINAL MID-UPPER LEVEL WAVE
WILL BE DAMPENING OUT AS IT MOVES EAST ACROSS OUR REGION WEDNESDAY
AFTERNOON AND EVENING. THIS WEAKENING TREND IS SUPPORTED BY THE
MODELS GIVEN THE EXPECTED INCREASING ZONAL FLOW ALOFT DURING THE
PERIOD. AT THE SURFACE... A COOL HIGH PRESSURE IS EXPECTED TO BECOME
FULLY ESTABLISHED FROM NEW ENGLAND SOUTHWARD INTO SC BY 12Z/WED.
THIS HIGH IS OF SUFFICIENT STRENGTH (1025+ MB) AND FAVORABLE
POSITION (NY AND PA) FOR THE DEVELOPMENT OF A SPRING TIME CAD EVENT
OVER OUR REGION. THE TEMPERATURES WEDNESDAY MAY STAY IN THE 50S FOR
MUCH OF THE PIEDMONT ESPECIALLY IF THE QPF OF 0.25 TO 0.50 FORECAST
BY MOST MODELS IS REALIZED.
THE MID LEVEL WAVE IS EXPECTED TO REMAIN STRONG ENOUGH TO HELP
GENERATE ENOUGH LIFT FOR LIGHT TO MODERATE STRATIFORM RAINS OVER OUR
REGION WEDNESDAY. THE BEST CHANCE OF RAIN APPEARS THAT IT WILL BEGIN
IN THE SW-W PIEDMONT EARLY IN THE DAY... THEN SPREAD EAST ACROSS
CENTRAL AND EASTERN AREAS DURING THE DAY. HIGHS WILL LIKELY BE ONLY
IN THE UPPER 50S NW TO UPPER 60S SE. IT APPEARS THAT THUNDER WOULD
BE HARD TO COME BY GIVEN THE DAMPENING WAVE ALOFT AND THE
STRENGTHENING CAD CONDITIONS/STABILITY NEAR THE SURFACE. WE WILL
CARRY LIKELY POP FOR RAIN IN THE WEST DURING THE MORNING... AND
CHANCES EAST... SPREADING THE LIKELY POP EAST TO COVER ALL ZONES BY
AFTERNOON AND EVENING. ONCE THE WAVE PASSES... THE RAIN IS EXPECTED
TO TAPER OFF BY 12Z/THU. WE WILL KEEP SOME LOW POP IN THE COASTAL
PLAIN THROUGH 15Z OR SO THU... FOLLOWED BY GRADUAL CLEARING DURING
THE DAY. THE CONTINUED NE FLOW WILL LIKELY MEAN A SLOW CLEARING
PATTERN. SKIES SHOULD BECOME PARTLY CLOUDY THU AFTERNOON AND
CONTINUE INTO FRIDAY AS WEAK HIGH PRESSURE WILL LINGER OVER NC...
BEFORE SHIFTING OFFSHORE FRIDAY. HIGHS THURSDAY AND FRIDAY WILL
RECOVER BACK INTO THE 70S RATHER SLOWLY.
FOR FRIDAY NIGHT THROUGH THE WEEKEND...
THE CONTINUES TO BE A LARGE SPREAD OF SOLUTIONS FOR AN EXPECTED EAST
COAST TROUGH/LOW PRESSURE DEVELOPMENT. THE LATEST GFS AND EC
INDICATE A COASTAL STORM BY LATE SAT-SUN WITH A CHILLY RAIN FOR
CENTRAL NC. PLAN NOW IS TO KEEP CURRENT FORECAST CONTINUITY... WITH
BEST CHANCE OF RAIN OVER THE WEEKEND. THE EC SOLUTION IS ON THE SW
SIDE OF THE ENVELOP OF SOLUTIONS (STRONG SURFACE LOW DEVELOPS OVER
NW GULF OF MEX SATURDAY... THEN DEEPENS (990 MB) AS IT RIDES NE OVER
NC SUNDAY. THIS SOLUTION IS ALSO ON THE EXTREME DEEP SIDE OF THE
OTHER GUIDANCE. HOWEVER... MOST SOLUTIONS INDICATE A POTENTIAL FOR
HEAVY RAIN... A PERIOD OF STRONG STORMS WITH THE ACTUAL COLD
FRONT... AND EVEN A TURN TO A CHILLY RAIN LATE IN THE WEEKEND. WE
WILL TREND THE FORECAST TOWARD A WETTER SOLUTION SAT-SUN.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
AS OF 145 PM MONDAY...
PRIMARY AVIATION IMPACTS DURING THE 18Z VALID TAF PERIOD WILL BE THE
GUSTY WINDS CONTINUING THROUGH THE AFTERNOON INTO THE EARLY
EVENING...AND AN APPROACH OF A COLD FRONT INTO CENTRAL NORTH
CAROLINA OVERNIGHT AND EARLY TUESDAY. THE LATEST GUIDANCE SUGGESTS
RELATIVELY LOW CHANCES FOR LOW CLOUDS OVERNIGHT...INSTEAD FOCUSING
ON ANY CLOUD DEVELOPMENT REMAINING IN THE VFR RANGE. WINDS WILL
START TO VEER FIRST IN THE TRIAD LIKELY IN VICINITY OF 08Z...AND
SLIGHTLY LATER TOWARD 10Z TO 12Z AT KRDU AND KRWI. THERE IS SOME
DIFFICULTY IN THE EXACT TIMING OF THE COLD FRONT TOWARD KFAY...AND
IT IS MORE LIKELY THAT KFAY WILL BE IN THE FRONTAL ZONE DURING
TUESDAY MORNING WITH A LIGHTER WIND VEERING MORE SLOWLY THAN
ELSEWHERE IN CENTRAL NORTH CAROLINA.
BEYOND THE 18Z VALID TAF PERIOD...ADVERSE AVIATION CONDITIONS IN
DEVELOPING SHOWERS AND THUNDERSTORMS...MORE NUMEROUS TOWARD KFAY...
EXIST TUESDAY AFTERNOON AND TUESDAY EVENING. THE LIKELIHOOD OF
SHOWERS AND SCATTERED THUNDERSTORMS MOVES NORTH TUESDAY NIGHT...AND
THE LIKELIHOOD OF IFR CEILINGS OUTSIDE OF ANY THUNDERSTORM BUILDS
GREATLY TOWARD THE TRIAD ESPECIALLY OVERNIGHT TUESDAY. WIDESPREAD
IFR CONDITIONS IN LOW CLOUDS BUILDS SOUTHEAST ENCOMPASSING ALL OF
CENTRAL NORTH CAROLINA BY WEDNESDAY NIGHT...BEFORE CONDITIONS SLOWLY
IMPROVE THURSDAY. THE NEXT BEST CHANCES FOR ADVERSE AVIATION
CONDITIONS OCCUR SATURDAY AND SATURDAY NIGHT.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DJF
NEAR TERM...DJF
SHORT TERM...VINCENT
LONG TERM...BADGETT
AVIATION...DJF
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
142 PM EDT MON APR 16 2012
.SYNOPSIS...
A COLD FRONT CROSSES THIS EVENING. A WAVE DEVELOPS ALONG THE FRONT
AND SKIRTS THE MOUNTAINS TUESDAY NIGHT THROUGH WEDNESDAY EVENING.
WARMER AFTERNOON TEMPERATURES RETURN FOR THE END OF THE WORK WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
130 PM UPDATE...TO REMOVE MENTION OF SEVERE TSTM POTENTIAL THIS
AFTERNOON AS SPC HAS PULLED US OUT OF SLIGHT RISK. THIS IS
REASONABLE GIVEN HI RES MODEL AND SOUNDING TRENDS. HAVE DEPICTED TWO
AREAS TO CONCENTRATE BEST CHANCE OF RASH/TRW THIS AFTERNOON. THE BEST
IS ACROSS THE SOUTH WHERE BETTER MOISTURE POOLING IS...AND SECONDARY
AREA ACROSS THE NORTHWEST WHERE BETTER DYNAMICS ARE. ALSO INCREASED
CLOUDS THIS AFTERNOON PER CURRENT SATELLITE TRENDS.
OTHERWISE...TEMPS LOOK GOOD DESPITE CLOUDS.
10 AM UPDATE. MAIN CHANGE WAS TO INCREASE WIND GUSTS TO 30 TO 40 MPH
THIS AFTERNOON...GIVEN STRONGER WINDS OFF THE SURFACE AND MIXING.
HOWEVER...RELATIVE HUMIDITIES WILL REMAIN HIGH ENOUGH TO PRECLUDE A
FIRE DANGER STATEMENT. CURRENT BAND OF SHOWERS DISSIPATING TO OUR
WEST AS INDICATED BY MODELS. AM CONCERNED ABOUT PROSPECTS OF
REDEVELOPMENT OF STORMS THIS AFTERNOON AHEAD OF FRONT AS SOUNDING
PROFILES LACK DEEPER MOISTURE. BUT WILL KEEP POPS AS IS THIS
AFTERNOON...GIVEN DYNAMICS ARE THERE FOR THAT THIN LINE AHEAD OF THE
FRONT AND SPC STILL HAS US IN A SLIGHT RISK OF SEVERE.
PREVIOUS DISCUSSION BELOW...
TIMING OF FRONT AND PREFRONTAL ACTION LOOKS GOOD FROM PREV FCST.
CONCERNED ABOUT POTENTIAL LACK OF REDEVELOPMENT OF PREFRONTAL BAND
THIS AFTN. MDLS ARE NOT THRILLED WITH BAND LIGHTING BACK UP AS IT
ENTERS WESTERN ZONES BY 18Z. RAPID RUC ALSO LACKLUSTER WITH ITS
MODELED REFLECTIVITY FOR TOMORROW. GIVEN THIS AND STOUT RIDGE
CURRENTLY OVER THE AREA AMID A DRY BL AND THE FACT THIS WILL BE
RACING OUT WELL AHEAD OF ACTUALLY BAROCLINIC ZONE...ELECTED TO
KNOCK DOWN POPS SOME BUT NOT DOWN TO WHAT MDLS SUGGEST. THINKING
OF MORE ISO OR SCT CONCERNING COVERAGE WITH GREATEST COVERAGE
ALONG AND WEST OF OH RVR WITH SUBSEQUENT WEAKENING TOWARD MTNS.
MDL QPF LOOKS MEAGER TO SAY THE LEAST GIVEN LACK OF COVERAGE AND
PROGRESSIVE NATURE. WHAT CONVECTION THAT DOES FORM WILL HAVE TO BE
WATCHED FOR DAMAGING WIND GUSTS AS SPC CONT TO PAINT MUCH
OF CWA IN SLIGHT RISK. AS A RESULT WILL CONT WIND WORDING IN WX GRIDS.
ACTUAL FRONT WILL LAG SEVERAL HRS BEHIND...NOT GETTING INTO SE
OH UNTIL AFTER 00Z...WITH SUBSEQUENT OH RVR CROSSING BY 03Z AND
EXITING MTNS BY 09Z. ELECTED TO HAVE SOME SCHC POPS WITH ACTUAL
FROPA AS ENOUGH FORCING AND MOISTURE MAY EXIST FOR A FEW SHRA.
SHOULD BE WINDY TDY WITH AFTN MIXING AND GRADIENT TIGHTENING.
COULD SEE SOME 25 TO 30KTS GUSTS WITH LCL HIGHER IN ANY CONVECTION
AND WITH FROPA.
CLDS WILL STICK ARND TONIGHT WITH MID/HI LVL MOISTURE ADVECTING IN
FROM SW FLOW ALOFT.
FOR TMPS...LEANED TOWARD WARMER MAV EAST OF OH RVR AND COOLER MET
WEST OF THERE AS CONVECTION WOULD BE FIRING BEFORE MAX HEATING
COULD OCCUR THERE. WILL ALSO GO A HAIR ABV GUIDANCE E AND S FOR
TONIGHT AS BL SLOW TO COOL AND LINGERING CLDS.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
GFS/CANADIAN AND ECMWF ARE SHOWING A WAVE DEVELOPING AND SKIRTING
SOUTHERN AND EASTERN PORTIONS OF THE FORECAST AREA FOR TUESDAY NIGHT
THROUGH WEDNESDAY EVENING. NAM KEEPS THE WAVE SOUTH OF THE
REGION...BUT IS AN OUTLIER. THEREFORE WILL GO WITH A MAJORITY
SOLUTION AND PUSH POPS DEEPER INTO OUR TERRITORY AND INCREASE THEM
IN THE SOUTHEAST. THIS WILL ALSO NECESSITATE LOWERING HIGH
TEMPERATURES ON WEDNESDAY IN THE SOUTHERN AND EASTERN COUNTIES.
CANADIAN/GFS AND ECMWF ARE VERY SIMILAR WITH THE NEXT SYSTEM AS
WELL. THE MODELS WOULD KEEP AN APPROACHING FRONT NORTH OF THE
REGION. WILL KEEP JUST A SMALL POP IN THE NORTH THURSDAY
AFTERNOON...BUT THEN DRY GO THURSDAY NIGHT AS THE FRONT RETREATS
FURTHER NORTH. WITH AREA IN THE WARM SECTOR...WARMED HIGH
TEMPERATURES ON THURSDAY AND FRIDAY.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
QUITE A BIT OF UNCERTAINTY IN THE LONG TERM PERIOD AS MODELS HAVE
RUN TO RUN CONSISTENCY AND OVERALL AGREEMENT ISSUES. BUT GENERAL
CONSENSUS IS THAT A COLD FRONT IN ASSOCIATION WITH A LOW PRESSURE
SYSTEM MOVING EAST THROUGH CANADA WILL STALL OUT SOMEWHERE OVER THE
NORTHERN ZONES LATE THURSDAY/EARLY FRIDAY...WITH A LOW PRESSURE
SYSTEM OUT IN THE PLAINS MOVING NORTHEAST ALONG THE STALLED FRONTAL
BOUNDARY TOWARDS THE REGION FOR THE WEEKEND. THE LOW PRESSURE SYSTEM
AND ASSOCIATED COLD FRONT WILL PUSH EAST THROUGH THE REGION FRIDAY
THROUGH SATURDAY NIGHT...SPREADING SHOWERS AND THUNDERSTORMS INTO
THE REGION. THE LOW WILL MOVE OFF TO THE NORTHEAST ON SUNDAY...WITH
MUCH COOLER AIR FILTERING INTO THE REGION ON THE BACK SIDE OF THE
LOW. ANY LINGERING PRECIPITATION/MOISTURE IN THE NW UPSLOPE FLOW ON
THE BACK SIDE OF THE LOW COULD BE IN THE FORM OF A RAIN/SNOW MIX OR
EVEN SNOW OVER THE NORTHERN MOUNTAIN ZONES AS THE COLDER AIR TAKES
OVER ON THE BACK SIDE OF THE LOW.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
18Z MONDAY THRU 18Z TUESDAY...
PREDOMINATE VFR CEILINGS WILL PREVAIL THROUGH THE PERIOD...WITH
CLEARING ACROSS NORTHWEST HALF EARLY TONIGHT. GUSTY SW WINDS 30 TO
40 KTS THIS AFTERNOON AS A COLD FRONT APPROACHES FROM THE WEST LATE
TDY...DIMINISHING EARLY TONIGHT AS THE COLD FRONT EXITS AND WITH
LOSS OF HEATING AND MIXING.
A LINE OF SCATTERED TO BROKEN SHOWERS AND THUNDERSTORMS MAY MOVE
ACROSS THE AREA ROUGHLY BETWEEN 17Z-00Z AHEAD OF THE FRONT...BEST
CHANCE WILL BE ACROSS THE SOUTH. WILL MINIMIZE THIS IN TAFS. HAVE
SOME TEMPO MVFR VSBY IN ANY TSTM THAT DOES FLARE UP.
AFTER 00Z...AS FRONT MOVES EAST OF AREA SHOWERS BASICALLY END WITH
VFR CONDITIONS PREVAILING.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z TUESDAY...
FORECAST CONFIDENCE...HIGH.
ALTERNATE SCENARIOS: WIND DIRECTION AND SPEED WILL TEND TO
FLUCTUATE. TIMING OF SHOWERS/THUNDERSTORMS MAY VARY.
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 18 19 20 21 22 23 00 01 02 03 04 05
EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01
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 H H H H H H H H H H H H
EKN CONSISTENCY H 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 H H H H H H H H H H H
AFTER 18Z TUESDAY...
IFR CONDITIONS POSSIBLE TUESDAY NIGHT THROUGH WEDNESDAY EVENING IN
SOUTHWEST VIRGINIA AND THE SOUTHERN WV MOUNTAINS.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...RPY/JMV/30
NEAR TERM...JMV
SHORT TERM...RPY
LONG TERM...SL
AVIATION...JMV
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1239 PM EDT MON APR 16 2012
.SYNOPSIS...
A COLD FRONT OVER NW OHIO WILL MOVE EAST THROUGH THE AREA THIS AFTERNOON
THEN HIGH PRESSURE WILL CROSS THE REGION LATE TUESDAY INTO EARLY
WEDNESDAY. ANOTHER COLD FRONT WILL DROP INTO THE OHIO VALLEY EARLY
THURSDAY AND STALL. LOW PRESSURE WILL MOVE ALONG THE FRONT UP THE
OHIO VALLEY FRIDAY AND TO THE MID ATLANTIC COAST SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
COLD FRONT AT 16Z WAS LOCATED FROM NEAR A LINE FROM SANDUSKY TO MARION.
AT THIS POINT THERE ARE NO RADAR RETURNS ALONG OR AHEAD OF THIS
BOUNDARY. THERE STILL MAY BE JUST ENOUGH CONVERGENCE ALONG THE
COLD FRONT AS IT INTERACTS WITH THE UNSTABLE AIR ACROSS THE
EASTERN COUNTY WARNING AREA. IT STILL COULD DEVELOP NEAR OR EAST
OF CANTON TO ASHTABULA LINE BETWEEN 18Z AND 20Z. IF THE THUNDERSTORMS
DO DEVELOP WE WILL HAVE TO MONITOR FOR THE POTENTIAL OF A STRONGER
WIND GUST.
GUSTY SOUTHWEST WINDS WILL BE AN ISSUE THROUGH THE AFTERNOON.
INITIALLY THE LOW LEVEL JET AHEAD OF THE FRONT WILL MIX TO THE
SURFACE AND SHOULD PRODUCE SOME GUSTS THAT ARE AROUND 45 KNOTS.
THESE WINDS WILL REMAIN STRONG IN THE WAKE OF THE FRONT FOR A FEW
HOURS AS THE STRONG PRESSURE RISES MOVE IN BEHIND THE LOW PRESSURE
THAT IS TRACKING THROUGH THE CENTRAL LAKES. SO EXPECT TO SEE GUSTS
IN THE WAKE OF THE FRONT CONTINUE IN THE 45 MPH RANGE. UNCERTAINTY
AT THIS POINT IS WHEN TO DECREASE THE WINDS. FOR NOW THE ADVISORY
TIME ENDING OF 10 PM LOOKS REASONABLE.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
HIGH PRESSURE BUILDS IN FROM THE WEST TONIGHT SO STRONG WINDS WILL
DIMINISH FROM WEST TO EAST DURING THE EVENING BUT COULD STILL REMAIN
A LITTLE WINDY FOR THE SNOWBELT LAKESHORE INTO THE LATE NIGHT HOURS.
DRY PUNCH OF AIR BEHIND THE COLD FRONT SHIFTS INTO THE EAST DURING
THE EVENING. WRAP MOISTURE TRIES TO SPREAD EAST INTO THE CWA EARLY
TONIGHT BUT SUBSIDENCE WITH HIGH MOVING IN LOOKS TO BE TOO STRONG TO
ALLOW FOR ENOUGH CLOUDINESS TO PRODUCE ANY PRECIP.
HIGH PRESSURE WITH DRY CONDITIONS SHOULD OCCUR INTO WED NIGHT THEN
ANOTHER COLD FRONT WILL MOVE IN BRINGING A THREAT FOR SHRA MAINLY
FOR THE SECOND HALF OF WED NIGHT.
THE QUESTION FOR THU IS WHETHER THE FRONT WILL HAVE ENOUGH MOMENTUM
TO PUSH FAR ENOUGH S TO TAKE THE SHRA THREAT SOUTH OF THE CWA FOR
THU AFTERNOON AND EVENING. LOW PRESSURE WILL MOVE ALONG THE FRONT
AND SPREAD SHRA BACK NORTH OF THE FRONT THU NIGHT. RIGHT NOW MODELS
WANT TO KEEP GOOD DEEP MOISTURE OVER THE CWA LATE THU AND THU NIGHT
SO WILL SIDE WITH CAUTION AND KEEP THREAT FOR SHRA GOING ALL DAY THU
AS WELL AS THU NIGHT.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
ANOTHER COLD FRONT MOVES THROUGH ON FRIDAY WITH A FAIR AMOUNT OF
COLD AIR BEHIND IT. THE LAKE AND 850 MB TEMPERATURE DIFFERENCE WILL
BE NEAR 11 OR 12C. HIGH PRESSURE SLOWLY BUILDS IN FROM THE WEST. THE
GFS AND ECMWF ARE IN FAIR AGREEMENT FRIDAY AND SATURDAY. FOR SUNDAY
THE 00Z ECMWF HANGS UNTO THE PRECIPITATION LONGER IN THE FORECAST
AREA. AT THIS TIME REMAINED CONSISTENT WITH THE PREVIOUS FORECAST
BUT THIS WILL HAVE TO BE WATCHED. TEMPERATURES WILL BE BELOW NORMAL.
THE THREAT OF FROST IS POSSIBLE SATURDAY NIGHT BUT ESPECIALLY SUNDAY
NIGHT IF THE CLOUDS DECREASE AS EXPECTED.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
GUSTY WINDS AND A THREAT OF THUNDER ARE THE WEATHER PROBLEMS FOR
TODAY. THE SHOWERS OVER EASTERN INDIANA AND WESTERN OHIO ARE
DECREASING AS THEY MOVE EAST...THE HRRR MODEL CONCURS WITH THIS.
THE MODELS ARE TRYING TO FORECAST A NARROW SQUALL LINE DEVELOPING AHEAD
OF THE FRONT LATE THIS MORNING AND IT WILL MOVE EAST RAPIDLY. THINGS MAY
BE MOVING QUICKER AND THIS MAY LIMIT THE AMOUNT OF THUNDER AND
SEVERE WEATHER. THE BEST CHANCE FOR THUNDER IS FROM CLE EAST AS
THE AIRMASS WILL GET UNSTABLE ENOUGH. THE 00Z 4KM WRF-NMM HAS TWO
NARROW BANDS OF SHOWERS...ONE MOVES THROUGH BY EARLY AFTERNOON AND
THEN ANOTHER DEVELOPS LATE IN THE AFTERNOON. THE 4KM WRF IS THE
ONLY MODEL SHOWING THIS. ON THE EDGE ABOUT THIS.
THE PRESSURE GRADIENT INCREASED SO MOST PLACES ARE GUSTY...THUS
DECREASING THE THREAT OF SIGNIFICANT LOW LEVEL WIND SHEAR-LLWS.
THE HRRR MODEL INCREASES THE GUSTS AT THE SURFACE IN EXCESS OF 40
KNOTS BY NOON IN THE WARM ADVECTION. GETTING SOME SUNSHINE AT
TIMES WILL HELP. AT DAYBREAK SOME GUSTS TO 35 KNOTS WERE ALREADY
BEING REPORTED. THE WINDS WILL DECREASE AROUND SUNSET.
VFR FOR CLOUDS AND VISIBILITY EXCEPT IN SHOWERS AND THUNDERSTORMS.
HOWEVER...THE SREF IS TRYING TO INDICATE MVFR CEILINGS DEVELOPING
THIS MORNING AND ENDING THIS AFTERNOON. SOME MVFR CEILINGS HAVE
DEVELOPED IN INDIANA...BUT AS THE SHOWERS DECREASE...THE CLOUDS
MAY ALSO. WILL FORECAST SOME MVFR CEILINGS FOR TOL AND FDY.
.OUTLOOK...NON VFR POSSIBLE WEDNESDAY NIGHT INTO FRIDAY.
&&
.MARINE...
STRONG WARM ADVECTION WILL OCCUR THIS MORNING UNTIL THE COLD FRONT
BEGINS MOVING ACROSS LAKE ERIE FROM WEST TO EAST THIS AFTERNOON.
EVEN THOUGH PLENTY OF WARM AIR AND STRONG WINDS ALOFT...SUSTAINED
WINDS OF 20 TO 25 KNOTS WILL BE LIKELY LATER THIS MORNING AND THEN
BEHIND THE FRONT SUSTAINED WINDS OF 30 KNOTS WITH HIGHER GUSTS. SOME
CONCERN THAT ESPECIALLY ON THE EAST END THE WINDS COULD APPROACH
GALE FORCE. THE COLD ADVECTION IS NOT THAT SIGNIFICANT SO WILL
CONTINUE WITH THE 30 KNOTS SUSTAINED AND A SMALL CRAFT ADVISORY. THE
WINDS WILL DECREASE FROM WEST TO EAST TUESDAY AS HIGH PRESSURE
BUILDS IN. UNTIL THAT HAPPENS THE WATER LEVEL ON THE WEST END OF
LAKE ERIE COULD DROP LATE THIS AFTERNOON AND EVENING. AT THIS TIME
IT IS NOT EXPECTED TO DROP TO BELOW THE CRITICAL MARK FOR SAFE
NAVIGATION...THIS WILL BE WATCHED CLOSELY BY THE NEXT SHIFTS.
SOME MINOR THREAT THAT WAVES COULD APPROACH SMALL CRAFT ADVISORY ON
THURSDAY AFTER A COLD FRONTAL PASSAGE. AT THIS TIME 2 TO 4 FOOT
WAVES SEEM TO BE THE HIGHEST.
THE NEXT THREAT OF A SMALL CRAFT ADVISORY WILL BE FRIDAY NIGHT INTO
SUNDAY AS A LOW AND FRONT MOVES NEAR LAKE ERIE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...WIND ADVISORY UNTIL 10 PM EDT THIS EVENING FOR OHZ003-006>014-
017>023-027>033-036>038-047-089.
PA...WIND ADVISORY UNTIL 10 PM EDT THIS EVENING FOR PAZ001>003.
MARINE...SMALL CRAFT ADVISORY UNTIL 4 PM EDT TUESDAY FOR LEZ147>149.
SMALL CRAFT ADVISORY UNTIL 10 AM EDT TUESDAY FOR LEZ142>146.
&&
$$
SYNOPSIS...ADAMS
NEAR TERM...MULLEN
SHORT TERM...ADAMS
LONG TERM...KIELTYKA
AVIATION...KIELTYKA
MARINE...KIELTYKA
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
319 PM CDT MON APR 16 2012
.SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT
319 PM CDT MON APR 16 2012
MAIN FORECAST CONCERNS ARE ON FREEZE TONIGHT AND PRECIPITATION
CHANCES FOR TUESDAY NIGHT...WEDNESDAY AND AGAIN THURSDAY.
CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RUC 500MB HEIGHT ANALYSIS
SHOWED RIDGING OVER THE WESTERN U.S....TROUGHING FROM ONTARIO INTO
TEXAS AND RIDGING ALONG THE EAST COAST OF THE U.S.. WITHIN THE
TROUGHING...A POTENT SHORTWAVE TROUGH WAS OVER UPPER MICHIGAN WHICH
HAS BEEN RESPONSIBLE FOR THE WINDY CONDITIONS LATELY...WHILE ANOTHER
SHORTWAVE WAS NEAR SIOUX FALLS SOUTH DAKOTA. THIS LATTER SHORTWAVE
WAS NOT DOING MUCH PRECIPITATION WISE...BUT THERE IS A DEFINITE BAND
OF LOW TO MID LEVEL CLOUDS COVERING MUCH OF THE DAKOTAS INTO
SOUTHWEST MINNESOTA. 12Z BIS SOUNDING WAS NEARLY SATURATED FROM 925
TO 700MB...SO THE SHORTWAVE DOES APPEAR TO BE SPREADING AT LEAST
CLOUDS EASTWARD. AHEAD OF THESE CLOUDS AND IN THE WAKE OF THE POTENT
TROUGH...THERE IS SOME CLEARING DROPPING DOWN THROUGH NORTHERN AND
CENTRAL MINNESOTA. WINDS ARE SLOWLY DIMINISHING ACROSS THE AREA DUE
TO A WEAKENING PRESSURE GRADIENT. SURFACE PRESSURE ANALYSIS SHOWED A
997MB LOW WAS LOCATED OVER THE EASTERN UPPER PENINSULA WHILE A RIDGE
OF HIGH PRESSURE WAS OVER THE DAKOTAS. THE WINDY NORTHWEST WINDS
HAVE DROPPED 850MB TEMPS DOWN TO -4 TO -8C OVER THE FORECAST AREA
PER RUC ANALYSIS...AND -10 TO -12C OVER NORTHERN WISCONSIN. THIS
COLD AIR LED TO SOME STRAIGHT SNOW OR RAIN/SNOW MIX OVER NORTHERN
PORTIONS OF THE FORECAST AREA THIS MORNING. 850MB TEMPS NOT MUCH
WARMER OVER THE DAKOTAS EITHER...-2 TO -6C...CONFIRMED TOO BY 12Z
RAOBS.
TONIGHT AND TUESDAY...UPPER LEVEL FLOW IS PROGGED TO BECOME MORE
ZONAL DURING THIS PERIOD AS A SHORTWAVE OFF THE PACIFIC NORTHWEST
COAST PLOWS INLAND ACROSS THE NORTHERN ROCKIES. FOR OUR AREA...WE
WILL HAVE A FEW SHORTWAVES MOVE THROUGH...THE FIRST OF WHICH IS THE
ONE NEAR SIOUX FALLS CROSSING THIS EVENING...THEN ANOTHER MUCH
WEAKER ONE SEEN ON WATER VAPOR OVER EASTERN MONTANA WHICH COMES
THROUGH TUESDAY MORNING. AGAIN...NOT ANTICIPATING ANY PRECIPITATION
WITH EITHER SHORTWAVE BECAUSE OF A LACK OF BOTH DYNAMICAL AND
ISENTROPIC LIFT. THEY WILL...HOWEVER...BRING AN INCREASE OF LOW TO
MID LEVEL STRATUS. SO AFTER WHAT COULD BE A BRIEF PERIOD OF CLEARING
THIS EVENING...MAINLY NORTH OF I-94 ASSOCIATED WITH THAT CLEARING
DROPPING DOWN THROUGH CENTRAL MINNESOTA...EXPECTING SKIES TO AT
LEAST TURN MOSTLY CLOUDY. LIKELY THE STRATUS SHOULD CLEAR OUT IN THE
WAKE OF THE SECOND SHORTWAVE...BUT THIS APPEARS BRIEF AS WELL.
LOOKING AT TUESDAY AFTERNOON...290-300 K ISENTROPIC LIFT REALLY
INCREASES DOWNSTREAM OF THAT SHORTWAVE COMING INTO THE ROCKIES...
RESULTING IN MORE MID LEVEL STRATUS. LIFT DOES NOT LOOK STRONG
ENOUGH TO PRODUCE PRECIPITATION...THOUGH. ALL OF THESE CLOUD
TRANSITIONS MAKE THE TEMPERATURE FORECAST DIFFICULT. IF IT WERE
CLEAR TONIGHT...THE SURFACE RIDGE MOVING IN AND HAVING 850MB TEMPS
IN THE 0 TO -6C RANGE IN PLACE WOULD BE VERY FAVORABLE FOR
TEMPERATURES TO PLUMMET WELL BELOW FREEZING. WITH THE CLOUDS MOVING
THROUGH TONIGHT...GENERALLY FOLLOWED CLOSE TO A BLEND OF THE 16.12Z
NAM12/16.09Z SREF MEAN. THE LOWS PROMPT THE NEED FOR A FREEZE
WARNING ALONG/NORTH OF I-94. LOWS MAY DIP TO FREEZING
ELSEWHERE...SUCH AS LA CROSSE...BUT CONFIDENCE IS NOT HIGH ENOUGH TO
ISSUE FREEZE WARNING DUE TO THE CLOUDS. FOR TUESDAY...RETURN FLOW
DOES HELP TO BOOST 850MB TEMPS UP TO 2-6C BY 00Z WEDNESDAY...BUT
TEMPERATURES WILL BE HELD BACK SOMEWHAT DUE TO THE CLOUDS. FOLLOWED
GENERALLY A BLEND OF GUIDANCE FOR HIGHS.
TUESDAY NIGHT AND WEDNESDAY...FOCUS IS ON THAT SHORTWAVE COMING OUT
OF THE ROCKIES. VERY GOOD MODEL AGREEMENT EXISTS THAT AS THE
SHORTWAVE CROSSES THE DAKOTAS AND LIFTS INTO FAR NORTHERN WISCONSIN
WEDNESDAY MORNING...IT WILL DEEPEN. IN RESPONSE TO THIS DEEPENING...
A STRONG SURGE OF SOUTHWEST 850MB MOISTURE TRANSPORT/ISENTROPIC LIFT
ON THE 290-295K SURFACE COMES ACROSS THE AREA TUESDAY EVENING.
SHOULD SEE SOME SHOWERS FALL IN THE EVENING. THERE IS SOME WEAK
CAPE...LESS THAN 200 J/KG...ENOUGH TO WARRANT A THUNDER MENTION.
AFTER MIDNIGHT INTO WEDNESDAY MORNING...THE COMBINATION OF HEIGHT
FALLS ALOFT WITH THE APPROACHING SHORTWAVE AND A PERSISTENT FLOW OF
850MB MOISTURE TRANSPORT SHOULD LEAD TO THE DEVELOPMENT OF A WARM
CONVEYOR BELT OF SHOWERS AND EMBEDDED THUNDERSTORMS. GIVEN DECENT
COVERAGE OF PRECIPITATION DEVELOPMENT...CAPE SHOULD STAY LIMITED AT
LESS THAN 500 J/KG...LIMITING ANY CHANCE FOR SEVERE WEATHER. THIS
WARM CONVEYOR BELT WILL TRACK WEST TO EAST ACROSS THE AREA THROUGH
WEDNESDAY MORNING. GIVEN GOOD MODEL CONSENSUS FOR PRECIPITATION...
HAVE RAISED PRECIPITATION CHANCES UP TO 80 PERCENT. A DRY SLOT THEN
ENTERS THE PICTURE FOR LATE WEDNESDAY MORNING INTO THE AFTERNOON...
PUNCHING IN FROM THE WEST IN THE WAKE OF THE SHORTWAVE TROUGH
LIFTING OFF TO THE NORTHEAST. THIS DRY SLOT SHOULD END PRECIPITATION
AND LIKELY RESULT IN A DECREASE IN CLOUDS. MUCH WARMER CONDITIONS
ANTICIPATED TUESDAY NIGHT WITH LOWS IN THE EVENING...THEN CLIMBING
SLIGHTLY AFTER MIDNIGHT WITH THE MOISTURE TRANSPORT SURGE. WARMER
850MB TEMPS OF 4-8C ON WEDNESDAY...PLUS SUN...WILL ALLOW FOR HIGHS
IN THE 60S TO EVEN 70.
WEDNESDAY NIGHT AND THURSDAY...THIS PERIOD FOCUS IS ON A COLLECTIONS
OF SHORTWAVES PROGGED TO MOVE INTO THE NORTHERN ROCKIES LATE
WEDNESDAY. HEIGHT FALLS DOWNSTREAM OF THESE SHORTWAVES HELP DEVELOP
A SURFACE LOW IN SOUTHEAST COLORADO. GOOD MODEL CONSENSUS EXISTS
THAT THE COLLECTION OF SHORTWAVES WILL DIG DOWN INTO THE CENTRAL
PLAINS WEDNESDAY NIGHT...LEADING TO A SHIELD OF DPVA AND DEFORMATION
FORCED PRECIPITATION DOWNSTREAM. AT THIS TIME IT APPEARS ANY
PRECIPITATION SHOULD HOLD OFF UNTIL THURSDAY. THERE ARE SOME ISSUES
THAT REMAIN FOR THURSDAY...THOUGH. ALTHOUGH GREAT MODEL AGREEMENT
EXISTS BETWEEN THE 16.12Z GFS/NAM/ECMWF/CANADIAN THAT MUCH OF THE
AREA SEES THAT DPVA AND DEFORMATION PRECIPITATION...THE
ECMWF/CANADIAN REMAIN FARTHER NORTH WITH THE ASSOCIATED SURFACE
SYSTEM. IF THESE HOLD TRUE...THUNDER CHANCES WOULD BE REQUIRED FOR
AT LEAST LOCATIONS SOUTH OF I-90. FOR NOW HAVE KEPT THUNDER OUT
GIVEN THAT IT RECENTLY WAS AND THE PERSISTENCE FOR MORE SOUTHERN
SOLUTIONS...BUT THIS WILL NEED TO BE WATCHED. CERTAINLY POTENTIAL
HERE FOR SOME DECENT QPE VALUES TOO...WITH CURRENT FORECAST QPF
ANYWHERE FROM 0.25 TO 0.75 INCHES.
.LONG TERM...THURSDAY NIGHT THROUGH MONDAY
319 PM CDT MON APR 16 2012
GOOD AGREEMENT REMAINS AMONGST 16.12Z GFS/ECMWF/CANADIAN AND GFS
ENSEMBLES ON SHOWING MAJOR AMPLIFICATION WITH THE UPPER FLOW DURING
THE LONG TERM PERIOD. RIDGING IN THE WESTERN U.S. DEVELOPS THURSDAY
NIGHT THROUGH SATURDAY WHILE A POTENT SHORTWAVE RIDES DOWN THE
RIDGE...FORMING A DEEP TROUGH OVER THE SOUTHEASTERN U.S. BY SATURDAY
NIGHT. BY MONDAY...A BLOCKED UP PATTERN IS FORECAST WITH STRONG
RIDGING OVER THE WESTERN U.S. AND A WIDE/DEEP CUT-OFF UPPER LOW OVER
THE EASTERN U.S.. THIS MEANS A COOL PATTERN FOR THE FORECAST
AREA...THOUGH OVERALL RELATIVELY DRY. REALLY ONLY PRECIPITATION TO
SPEAK OF IS THURSDAY NIGHT...ASSOCIATED WITH DEFORMATION AND DPVA
INDUCED RAIN FROM THURSDAY SLOWLY EXITING. ENOUGH COLD AIR DOES WRAP
DOWN INTO THE AREA FOR A MIX OR CHANGE OVER TO SNOW...THOUGH IT IS
CONCEIVABLE THE PRECIPITATION ENDS BEFORE THE COLDER AIR ARRIVES.
ALSO HAVE A SLIGHT CHANCE OF RAIN SHOWERS IN FOR SATURDAY NIGHT
WHERE THERE ARE SUGGESTIONS OF A SHORTWAVE DROPPING DOWN INTO THE
EASTERN TROUGH. ONLY KEPT AT 20 PERCENT GIVEN VERY FEW MODELS HAVE
THIS PRECIPITATION. IN FACT...LATER FORECASTS MAY BE ABLE TO PULL
THIS IF ALL MODELS TREND TOWARD THE ECMWF/GFS. OTHERWISE...
TEMPERATURES ARE THE STORY WHICH AGAIN LOOK TO HOLD BELOW NORMAL. IN
ADDITION...COULD BE DEALING WITH FREEZE WARNINGS FOR FRIDAY NIGHT
AND POSSIBLY SATURDAY NIGHT AS WELL...IF THE PRECIPITATION DOES NOT
MATERIALIZE. BEST CHANCE FOR FREEZE IS AGAIN ALONG AND NORTH OF
I-94. PERHAPS TOWARDS MONDAY WE WILL BE ABLE TO CLIMB BACK TO NEAR
OR ABOVE NORMAL WITH HINTS OF THE UPPER RIDGE TRYING TO BUILD
TOWARDS THE AREA.
&&
.AVIATION...THIS AFTERNOON THROUGH TUESDAY
1225 PM CDT MON APR 16 2012
THE STRONG LOW PRESSURE SYSTEM CONTINUED TO MOVE QUICKLY AWAY FROM
THE AREA AT MID-DAY. THE STRONG WEST/NORTHWEST WINDS WERE BEGINNING
TO DECREASE AS THE GRADIENT RELAXED AND STRONGEST PRESSURE RISES
BEHIND THE LOW MOVED INTO NORTHERN WI. THE WINDS WILL CONTINUE TO
DECREASE THRU THE DAY THEN BECOME QUITE LIGHT THIS EVENING/OVERNIGHT
AS A RIDGE OF HIGH PRESSURE QUICKLY MOVES INTO MN/WI. THE HIGH WILL
ALREADY MOVE EAST OF THE AREA ON TUE WITH LIGHTER SOUTH WINDS
RETURNING TO THE TAF SITES. THE VFR/MVFR STRATUS ARE MORE
PROBLEMATIC. THE CLOUD DECK REMAINS MVFR WELL WEST OF THE AREA OVER
CENTRAL/NORTHERN MN AT MID-DAY...WITH THE FLOW TO ROTATE THESE
CLOUDS/MOISTURE SOUTHEAST ACROSS THE AREA INTO THIS EVENING.
DRYING/MIXING WITH THE MAIN LOW MOVING WELL EAST OF THE AREA SHOULD
ALLOW THE CIGS TO GRADUALLY RISE INTO THE 3K-4K FT LATER THIS
AFTERNOON/EVENING. CLOUD DECK SHOULD THEN SCATTER OUT THIS EVENING
WITH THE SFC-850MB RIDGE BUILDING IN...BUT ANOTHER MID-LEVEL
SHORTWAVE WILL SPIN ACROSS THE AREA DURING THE EVENING AND MAY
PROVIDE ENOUGH LIFT FOR THE CLOUD DECKS TO REMAIN BKN THRU THE
EVENING AND PERHAPS OVERNIGHT. SUBSIDENCE/FURTHER DRYING BEHIND THE
SHORTWAVE EXPECTED BRING A VFR DAY TO THE AREA ON TUE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
319 PM CDT MON APR 16 2012
WI...FREEZE WARNING FROM 1 AM TO 8 AM CDT TUESDAY FOR WIZ017-029-034-
042>044.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION.....RRS