Forecast Discussions mentioning any of
"HRRR" "RR" "RUC13" "RUC" received at GSD on 04/05/12
AREA FORECAST DISCUSSION
NWS PUEBLO CO
245 AM MDT TUE APR 3 2012
.UPDATE...
.SHORT TERM...HAVE PUT OUT A SHORT FUSE HIGH WIND WARNING DUE TO
PERSISTENT GUSTS OVER 60 MPH HERE AT KPUB AND AT A FEW SPOTS IN
EL PASO AS WELL. WIDESPREAD WINDS OVER 50 MPH STILL BEING
OBSERVED. ONGOING PRECIP IS BRINGING SOME HIGHER MOMENTUM AIR TO
THE GROUND...AND THIS SHOULD CONTINUE FOR AT LEAST THE NEXT
SEVERAL HOURS BEFORE WINDS GRADUALLY QUIET DOWN. WINTER HIGHLIGHTS
LOOK ON TRACK FOR MOST PART. NAM IS SHOWING EXTREMELY HEAVY SNOW
OVER THE SRN MTS AND ESPECIALLY SPANISH PEAKS REGION. WOULD NOT BE
SURPRISED TO SEE SPOTS LIKE CUCHARA GET WELL IN EXCESS OF 2 FEET
FROM THIS STORM. ROSE
&&
.PREV DISCUSSION... /ISSUED 1128 PM MDT MON APR 2 2012/
AVIATION...
IFR CIGS/VIS EXPECTED TO IMPACT THE TAF SITES FROM TONIGHT INTO
TUESDAY...ESPECIALLY AFTER 07Z/3RD AS INTENSE STORM SYSTEM SLOWLY
MOVES ACROSS NORTHERN NEW MEXICO. IN ADDITION...GUSTY NORTH WINDS
IN THE 25 TO 45 KT RANGE SHOULD CONTINUE AT BOTH KCOS AND KPUB
TAFS SITES TONIGHT. IT NOW APPEARS THAT THE HEAVIEST SNOW FOR KCOS
AND KPUB SHOULD BE NOTED FROM 07Z-15Z AND THEN POSSIBLY AGAIN FROM
21Z TUESDAY TO 03Z WEDNESDAY. KALS...KCOS AND KPUB COULD ALL
EXPERIENCE SOME ACCUMULATING SNOW FROM AFTER MIDNIGHT TONIGHT INTO
TUESDAY.
PREV DISCUSSION... /ISSUED 857 PM MDT MON APR 2 2012/
UPDATE...
WILL ALLOW HIGH WIND WARNING TO EXPIRE AS ONLY AREA EXCEEDING 50
KNOT GUSTS THE PAST 2 HOURS HAS BEEN HERE AT KPUB...WITH WINDS
DIMINISHING SLIGHTLY ELSEWHERE. HRRR SUGGESTS SOME 40-45 KNOT
GUSTS OVER EASTERN EL PASO AND NORTHERN PUEBLO COUNTIES STILL
POSSIBLE THROUGH 05Z...AND PERHAPS SOME BRIEF CONVECTIVE OUTFLOW
WINDS TO AROUND 45 KNOTS ACROSS PROWERS AND BACA COUNTIES FROM
TSRA IN KS.
PRECIP A LITTLE SLOW TO GET GOING THIS EVENING WITH DRY SURFACE
LAYER OVER EASTERN COLORADO AND DEEPEST LIFT JUST SOUTH OF THE
AREA. WILL NUDGE POPS DOWNWARD MANY AREAS THROUGH 06Z WITH THIS
UPDATE..ESPECIALLY KPUB/KCOS. 00Z NAM RAMPS UP PRECIP AFTER 06Z AS
DEEPER MOISTURE PUSHES WESTWARD...WITH A PROLONGED PERIOD OF
MODERATE/HEAVY RAIN AND SNOW CONTINUING WELL INTO TUES NIGHT. NAM
00Z QPF INDICATES LIQUID AMOUNTS OVER 2 INCHES OVER THE PALMER
DIVIDE AND ACROSS THE SOUTHERN SANGRES/WETS AND I-25 CORRIDOR FROM
PUEBLO SOUTHWARD...WHICH SUGGESTS FORECASTS OF 1 TO 2 FEET OF SNOW
OVER THE HIGHER TERRAIN LOOK ON TRACK. KCOS/KPUB/CANON CITY PRECIP
AMOUNTS STILL TRICKY WITH USUAL PRECIP MINIMUM NEARBY...THOUGH
STRENGTH OF ISENTROPIC UPGLIDE SHOULD OVERCOME DOWNSLOPE FLOW FOR
SEVERAL HOURS LATE TONIGHT INTO TUES. OVERALL TREND OF THE
FORECAST LOOKS GOOD. --10
PREV DISCUSSION... /ISSUED 400 PM MDT MON APR 2 2012/
SHORT TERM...
(TONIGHT AND TUESDAY)
STRONG SPRING STORM TAKING AIM ON SOUTH CENTRAL AND SOUTHEAST
COLORADO...
MODELS IN REMARKABLE AGREEMENT WITH THE OVERALL DETAILS OF CLOSED
UPPER LOW ACROSS EAST CENTRAL NEW MEXICO SHIFTING EASTWARD THEN
NORTHEASTWARD INTO THE TX/OK PANHANDLE BY TUES AFTERNOON. FRONT HAS
ALREADY SLAMMED THROUGH EASTERN CO EARLIER TODAY...WITH PEAK GUSTS
IN EXCESS OF 60 MPH ACROSS PORTIONS OF EL PASO COUNTY. HRRR AND
LOCAL 4 KM WRF INDICATED TWO PERIODS OF STRONGER WINDS...ONE THIS
MORNING...AND ANOTHER THIS AFTERNOON INTO EARLY THIS EVENING. JUST
PICKED UP A GUST TO 50 KTS AT KPUB AIRPORT AROUND 230 PM...SO
PERHAPS THE SHORT RANGE MODELS DO HAVE A HANDLE ON THIS.
THUS...WILL MAINTAIN HIGH WIND WARNINGS THROUGH 03Z.
INTERESTINGLY...HRRR SUGGESTS CORE OF STRONGER WINDS MAY EXPAND
ACROSS MORE OF THE SOUTHEAST PLAINS AND CONTINUE THROUGH
06Z...HOWEVER WITH TIGHTEST PRESSURE GRADIENT ALREADY PAST...WILL
LEAVE CURRENT EXPIRATION AT 03Z AND LET LATER SHIFTS MONITOR THE
TRENDS TO DECIDE IF EXTENSION IN TIME...OR EXPANSION IN AREA IS
NECESSARY. LOCAL 4 KM WRF BACKED OFF SOME ON WIND GUSTS AFTER 03Z
FOR ALL BUT PERHAPS EASTERN EL PASO COUNTY. OTHER AREA OF CONCERN
FOR HIGH WINDS CONTINUES ALONG THE EASTERN SIDE OF THE SAN LUIS
VALLEY AS WINDS ACCELERATE THROUGH THE PASSES IN THE SANGRES AND
SPILLS INTO THE VALLEY. HRRR AND 12Z 4KM WRF STILL PAINT THIS
SCENARIO IN THE LATEST RUNS...WITH PEAK WINDS OCCURRING NOW THROUGH
00Z...WITH GUSTS STARTING TO TAIL OFF BY 03Z. ALS HAD A WIND GUST
TO 54 MPH AFTER NOON...WHICH IS VERY CLOSE. SUSPECT LOCAL AREAS TO
THE WEST HAD HIGHER GUSTS. AGAIN...WRF KEEPS GUSTS UP AROUND 70 MPH
THROUGH 03Z BEFORE TAILING OFF...SO CURRENT HIGHLIGHT LOOKS ON
TARGET.
FIRST LOBE OF ENERGY WILL ROTATE AROUND THE CLOSED LOW INTO
SOUTHEAST COLORADO THIS EVENING. SNOW IS ALREADY OCCURRING ACROSS
THE EAST FACING SLOPES OF THE SANGRES/WETS...THOUGH ITS BEEN PRETTY
LIGHT SO FAR AS MOISTURE LAYER REMAINS SHALLOW. HOWEVER...RADARS TO
THE SOUTH SHOW ECHOES EXPANDING ACROSS NORTHEAST NM WITH SOME
EMBEDDED CONVECTION EVIDENT VIA LIGHTNING STRIKES. SHOULD SEE THIS
BAND OF SHOWERS SPREAD NORTHWARD THROUGH THE EVENING WITH SNOW
SPREADING NORTHWARD AND RAMPING UP ACROSS THE PIKES PEAK AREA AFTER
03-06Z. NICE ISENTROPIC UPGLIDE EVIDENT IN BOTH NAM AND GFS ON THE
300K SFC...AND MODELS IN GOOD AGREEMENT WITH HEAVY QPF AMOUNTS
ACROSS A LARGE PORTION OF THE SOUTHEAST PLAINS THROUGH
TUESDAY...PARTICULARLY NEAR THE MOUNTAINS. SNOW LEVELS WILL START OFF
AROUND 7000 FEET...BUT DROP TO AROUND 5000 FEET OVERNIGHT. TIMING
OF THE DROP IN TEMPERATURES AND THE RESIDUAL WARMTH OF THE GROUND
WILL PLAY A BIG ROLE IN HOW MUCH SNOW ACCUMULATES ACROSS THE LOWER
ELEVATIONS OF THE I-25 CORRIDOR SUCH AS SOUTHERN EL PASO AND PUEBLO
COUNTIES. HOWEVER...WITH GOOD MODEL CONSENSUS AND IMPRESSIVE TROWAL
ALOFT EXPECTED TO OVERWHELM DOWNSLOPE OFF THE PALMER AT LEAST
THROUGH THE 06Z TO 15Z WINDOW...HAVE OPTED TO ISSUE A WINTER WEATHER
ADVISORY FOR THE LOWER ELEVATIONS OF THE I-25 CORRIDOR...INCLUDING
COLORADO SPRINGS AND PUEBLO. SNOWFALL AMOUNTS WILL LIKELY EXHIBIT A
WIDE RANGE WITH SOME MELTING OFF ROAD SURFACES AT TIMES...BUT
ANYWHERE FROM 2 INCHES ON THE GRASS...TO AROUND 6 INCHES NEAR THE
MOUNTAINS SEEMS PLAUSIBLE. WITH A PERIOD OF EAST TO NORTHEAST WINDS
FUNNELING UP THE ARKANSAS RIVER...AND UPSLOPING ALONG THE WEST SIDE
OF THE LA GARITAS/AND EASTERN SAN JUANS...WILL INCLUDE THESE AREAS
IN A WINTER WEATHER ADVISORY AND RUN IT THROUGH 00Z. BIGGEST WINNER
IN THIS EVENT WILL BE THE EAST SLOPES OF THE SANGRES AND WETS 40 TO
50 KTS OF NORTHEAST UPSLOPE WILL RESULT IN 1 TO 2 FEET OF
SNOW...WITH HIGHER AMOUNTS ( UP TO 30 INCHES) ACROSS THE HIGHER
ELEVATIONS. REMAINDER OF THE HEADLINES IN GOOD SHAPE. TROWAL
EVENTUALLY PULLS OFF TO THE NORTHEAST ON TUESDAY WITH SNOW WINDING
DOWN FROM SOUTHWEST TO NORTHEAST DURING THE DAY ON TUESDAY. -KT
LONG TERM...
(TUESDAY NIGHT-MONDAY)
TIMING AND LOCATION OF UPPER LEVEL STORM LIFTING OUT ACROSS THE
SE PLAINS TUESDAY NIGHT THE MAIN FORECAST PROBLEM...
TUESDAY NIGHT-WEDNESDAY...SLIGHT MODEL DIFFERENCES ON TIMING AND
LOCATION OF UPPER LOW LIFTING OUT ACROSS THE SE PLAINS CONTINUE AND
HAVE TAILORED FORECAST TOWARDS THE NAM AND EC WHICH HAVE THE LOW
ACROSS EXTREME NORTHEAST NEW MEXICO AT 00Z WED AND THEN SLOWLY LIFT
IT OUT ACROSS WESTERN OKLAHOMA INTO CENTRAL OKLAHOMA THROUGH THE DAY
ON WEDNESDAY. ONGOING WRAP AROUND PRECIPITATION ACROSS THE EASTERN
MTS AND I-25 CORRIDOR TUESDAY AFTERNOON SLOWLY SHIFTS EAST AND
DIMINISHES FROM WEST TO EAST OVERNIGHT...AS UPPER LEVEL FLOW BECOMES
MORE NORTHWEST. COULD SEE SOME ADDITIONAL LIGHT ACCUMULATIONS OF A
COUPLE OF INCHES ACROSS THE NORTH AND EAST FACING SLOPES OF THE
EASTERN MTS AND ALONG WITH PALMER DVD AND RATON MESA TUESDAY EVENING
WITH THINGS WINDING INTO WEDNESDAY MORNING. TEMPERATURES ALOFT WARM
FROM WEST TO EAST THROUGH THE DAY ON WEDNESDAY...AS UPPER LEVEL
RIDGING BUILDS INTO THE STATE WITH HIGHS WARMING BACK TO AT OR
SLIGHTLY ABOVE SEASONAL AVERAGES...THOUGH HAVE TAPERED BACK HIGHS A
TAD IN EXPECTED SNOW COVERED AREAS.
WEDNESDAY NIGHT-MONDAY...WARMER AND DRIER WEATHER CONTINUES TO BE
PROGGED THROUGH THE PERIOD...WITH MODERATE TO STRONG WESTERLY FLOW
EXPECTED ACROSS THE REGION AS SEVERAL SHORT WAVES MOVE ACROSS THE
NORTHERN ROCKIES. ONE WAVE MOVES ACROSS THE REGION THURSDAY NIGHT
AND FRIDAY...WITH BREEZY TO WINDY CONDITIONS AND POSSIBLE CRITICAL
FIRE WEATHER CONDITIONS ON FRIDAY...DEPENDING ON HOW MUCH PRECIP
FALLS. PASSING WAVE SENDS A DRY COLD FRONT ACROSS THE PLAINS FRIDAY
WITH SLIGHTLY COOLER TEMPERATURES ACROSS THE AREA ON SATURDAY.
ANOTHER WAVE POSSIBLE MOVES ACROSS THE NORTHERN ROCKIES ON SUNDAY
NIGHT...WITH A BACKDOOR COLD FRONT POSSIBLE BRINGING IN ENOUGH LOW
LEVEL MOISTURE FOR A FEW SHOWERS ACROSS THE EASTERN PLAINS ON
MONDAY. HOWEVER...WILL KEEP A DRY FORECAST IN TACT THROUGH THE
PERIOD. -MW
AVIATION...
IFR CIGS/VIS EXPECTED TO AFFECT THE TAF SITES TONIGHT AS STRONG
SYSTEM MOVES ACROSS NORTHERN NEW MEXICO. STRONG NORTH WINDS IN THE
30 TO 45 KT RANGE WILL CONTINUE AT KCOS AND KPUB BEFORE DECREASING
TOWARDS 06Z. KALS WILL CONTINUE TO SEE EAST WINDS IN THE 25 TO 40
KT RANGE THROUGH EARLY EVENING WITH PERIODS OF BLDU. HEAVIEST SNOW
WILL IMPACT KCOS AND KPUB BETWEEN 06Z-18Z PERIOD WITH POTENTIAL FOR
A COUPLE INCHES OF SNOW...MAINLY ON GRASSY SURFACES AT KPUB...TO
AROUND 2 TO 5 INCHES AT KCOS. WITH WARM GROUND...THERE WILL BE SOME
MELTING AT TIMES AT KCOS...BUT PAVED SURFACES COULD BECOME SLUSHY
AND SNOWPACKED UNDER THE HEAVIER SNOW BANDS. KALS COULD SEE AN INCH
OR TWO AS WELL. RAIN/SNOW SWITCH OVER WILL OCCUR AROUND 03Z FOR
KCOS AND KALS...AND AROUND 06Z FOR KPUB. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 6 PM MDT THIS EVENING FOR COZ072>075-
078>082-084-087-088.
WINTER WEATHER ADVISORY UNTIL 6 PM MDT THIS EVENING FOR COZ058-
060>063-066>068-076-077.
HIGH WIND WARNING UNTIL 6 AM MDT WEDNESDAY FOR COZ084>086.
WINTER WEATHER ADVISORY UNTIL NOON MDT TODAY FOR COZ083-085-086.
&&
$$
44/50
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1128 PM MDT MON APR 2 2012
.AVIATION...
IFR CIGS/VIS EXPECTED TO IMPACT THE TAF SITES FROM TONIGHT INTO
TUESDAY...ESPECIALLY AFTER 07Z/3RD AS INTENSE STORM SYSTEM SLOWLY
MOVES ACROSS NORTHERN NEW MEXICO. IN ADDITION...GUSTY NORTH WINDS
IN THE 25 TO 45 KT RANGE SHOULD CONTINUE AT BOTH KCOS AND KPUB
TAFS SITES TONIGHT. IT NOW APPEARS THAT THE HEAVIEST SNOW FOR KCOS
AND KPUB SHOULD BE NOTED FROM 07Z-15Z AND THEN POSSIBLY AGAIN FROM
21Z TUESDAY TO 03Z WEDNESDAY. KALS...KCOS AND KPUB COULD ALL
EXPERIENCE SOME ACCUMULATING SNOW FROM AFTER MIDNIGHT TONIGHT INTO
TUESDAY.
&&
.PREV DISCUSSION... /ISSUED 857 PM MDT MON APR 2 2012/
UPDATE...
WILL ALLOW HIGH WIND WARNING TO EXPIRE AS ONLY AREA EXCEEDING 50
KNOT GUSTS THE PAST 2 HOURS HAS BEEN HERE AT KPUB...WITH WINDS
DIMINISHING SLIGHTLY ELSEWHERE. HRRR SUGGESTS SOME 40-45 KNOT
GUSTS OVER EASTERN EL PASO AND NORTHERN PUEBLO COUNTIES STILL
POSSIBLE THROUGH 05Z...AND PERHAPS SOME BRIEF CONVECTIVE OUTFLOW
WINDS TO AROUND 45 KNOTS ACROSS PROWERS AND BACA COUNTIES FROM
TSRA IN KS.
PRECIP A LITTLE SLOW TO GET GOING THIS EVENING WITH DRY SURFACE
LAYER OVER EASTERN COLORADO AND DEEPEST LIFT JUST SOUTH OF THE
AREA. WILL NUDGE POPS DOWNWARD MANY AREAS THROUGH 06Z WITH THIS
UPDATE..ESPECIALLY KPUB/KCOS. 00Z NAM RAMPS UP PRECIP AFTER 06Z AS
DEEPER MOISTURE PUSHES WESTWARD...WITH A PROLONGED PERIOD OF
MODERATE/HEAVY RAIN AND SNOW CONTINUING WELL INTO TUES NIGHT. NAM
00Z QPF INDICATES LIQUID AMOUNTS OVER 2 INCHES OVER THE PALMER
DIVIDE AND ACROSS THE SOUTHERN SANGRES/WETS AND I-25 CORRIDOR FROM
PUEBLO SOUTHWARD...WHICH SUGGESTS FORECASTS OF 1 TO 2 FEET OF SNOW
OVER THE HIGHER TERRAIN LOOK ON TRACK. KCOS/KPUB/CANON CITY PRECIP
AMOUNTS STILL TRICKY WITH USUAL PRECIP MINIMUM NEARBY...THOUGH
STRENGTH OF ISENTROPIC UPGLIDE SHOULD OVERCOME DOWNSLOPE FLOW FOR
SEVERAL HOURS LATE TONIGHT INTO TUES. OVERALL TREND OF THE
FORECAST LOOKS GOOD. --10
PREV DISCUSSION... /ISSUED 400 PM MDT MON APR 2 2012/
SHORT TERM...
(TONIGHT AND TUESDAY)
.STRONG SPRING STORM TAKING AIM ON SOUTH CENTRAL AND SOUTHEAST
COLORADO...
MODELS IN REMARKABLE AGREEMENT WITH THE OVERALL DETAILS OF CLOSED
UPPER LOW ACROSS EAST CENTRAL NEW MEXICO SHIFTING EASTWARD THEN
NORTHEASTWARD INTO THE TX/OK PANHANDLE BY TUES AFTERNOON. FRONT HAS
ALREADY SLAMMED THROUGH EASTERN CO EARLIER TODAY...WITH PEAK GUSTS
IN EXCESS OF 60 MPH ACROSS PORTIONS OF EL PASO COUNTY. HRRR AND
LOCAL 4 KM WRF INDICATED TWO PERIODS OF STRONGER WINDS...ONE THIS
MORNING...AND ANOTHER THIS AFTERNOON INTO EARLY THIS EVENING. JUST
PICKED UP A GUST TO 50 KTS AT KPUB AIRPORT AROUND 230 PM...SO
PERHAPS THE SHORT RANGE MODELS DO HAVE A HANDLE ON THIS.
THUS...WILL MAINTAIN HIGH WIND WARNINGS THROUGH 03Z.
INTERESTINGLY...HRRR SUGGESTS CORE OF STRONGER WINDS MAY EXPAND
ACROSS MORE OF THE SOUTHEAST PLAINS AND CONTINUE THROUGH
06Z...HOWEVER WITH TIGHTEST PRESSURE GRADIENT ALREADY PAST...WILL
LEAVE CURRENT EXPIRATION AT 03Z AND LET LATER SHIFTS MONITOR THE
TRENDS TO DECIDE IF EXTENSION IN TIME...OR EXPANSION IN AREA IS
NECESSARY. LOCAL 4 KM WRF BACKED OFF SOME ON WIND GUSTS AFTER 03Z
FOR ALL BUT PERHAPS EASTERN EL PASO COUNTY. OTHER AREA OF CONCERN
FOR HIGH WINDS CONTINUES ALONG THE EASTERN SIDE OF THE SAN LUIS
VALLEY AS WINDS ACCELERATE THROUGH THE PASSES IN THE SANGRES AND
SPILLS INTO THE VALLEY. HRRR AND 12Z 4KM WRF STILL PAINT THIS
SCENARIO IN THE LATEST RUNS...WITH PEAK WINDS OCCURRING NOW THROUGH
00Z...WITH GUSTS STARTING TO TAIL OFF BY 03Z. ALS HAD A WIND GUST
TO 54 MPH AFTER NOON...WHICH IS VERY CLOSE. SUSPECT LOCAL AREAS TO
THE WEST HAD HIGHER GUSTS. AGAIN...WRF KEEPS GUSTS UP AROUND 70 MPH
THROUGH 03Z BEFORE TAILING OFF...SO CURRENT HIGHLIGHT LOOKS ON
TARGET.
FIRST LOBE OF ENERGY WILL ROTATE AROUND THE CLOSED LOW INTO
SOUTHEAST COLORADO THIS EVENING. SNOW IS ALREADY OCCURRING ACROSS
THE EAST FACING SLOPES OF THE SANGRES/WETS...THOUGH ITS BEEN PRETTY
LIGHT SO FAR AS MOISTURE LAYER REMAINS SHALLOW. HOWEVER...RADARS TO
THE SOUTH SHOW ECHOES EXPANDING ACROSS NORTHEAST NM WITH SOME
EMBEDDED CONVECTION EVIDENT VIA LIGHTNING STRIKES. SHOULD SEE THIS
BAND OF SHOWERS SPREAD NORTHWARD THROUGH THE EVENING WITH SNOW
SPREADING NORTHWARD AND RAMPING UP ACROSS THE PIKES PEAK AREA AFTER
03-06Z. NICE ISENTROPIC UPGLIDE EVIDENT IN BOTH NAM AND GFS ON THE
300K SFC...AND MODELS IN GOOD AGREEMENT WITH HEAVY QPF AMOUNTS
ACROSS A LARGE PORTION OF THE SOUTHEAST PLAINS THROUGH
TUESDAY...PARTICULARLY NEAR THE MOUNTAINS. SNOW LEVELS WILL START OFF
AROUND 7000 FEET...BUT DROP TO AROUND 5000 FEET OVERNIGHT. TIMING
OF THE DROP IN TEMPERATURES AND THE RESIDUAL WARMTH OF THE GROUND
WILL PLAY A BIG ROLE IN HOW MUCH SNOW ACCUMULATES ACROSS THE LOWER
ELEVATIONS OF THE I-25 CORRIDOR SUCH AS SOUTHERN EL PASO AND PUEBLO
COUNTIES. HOWEVER...WITH GOOD MODEL CONSENSUS AND IMPRESSIVE TROWAL
ALOFT EXPECTED TO OVERWHELM DOWNSLOPE OFF THE PALMER AT LEAST
THROUGH THE 06Z TO 15Z WINDOW...HAVE OPTED TO ISSUE A WINTER WEATHER
ADVISORY FOR THE LOWER ELEVATIONS OF THE I-25 CORRIDOR...INCLUDING
COLORADO SPRINGS AND PUEBLO. SNOWFALL AMOUNTS WILL LIKELY EXHIBIT A
WIDE RANGE WITH SOME MELTING OFF ROAD SURFACES AT TIMES...BUT
ANYWHERE FROM 2 INCHES ON THE GRASS...TO AROUND 6 INCHES NEAR THE
MOUNTAINS SEEMS PLAUSIBLE. WITH A PERIOD OF EAST TO NORTHEAST WINDS
FUNNELING UP THE ARKANSAS RIVER...AND UPSLOPING ALONG THE WEST SIDE
OF THE LA GARITAS/AND EASTERN SAN JUANS...WILL INCLUDE THESE AREAS
IN A WINTER WEATHER ADVISORY AND RUN IT THROUGH 00Z. BIGGEST WINNER
IN THIS EVENT WILL BE THE EAST SLOPES OF THE SANGRES AND WETS 40 TO
50 KTS OF NORTHEAST UPSLOPE WILL RESULT IN 1 TO 2 FEET OF
SNOW...WITH HIGHER AMOUNTS ( UP TO 30 INCHES) ACROSS THE HIGHER
ELEVATIONS. REMAINDER OF THE HEADLINES IN GOOD SHAPE. TROWAL
EVENTUALLY PULLS OFF TO THE NORTHEAST ON TUESDAY WITH SNOW WINDING
DOWN FROM SOUTHWEST TO NORTHEAST DURING THE DAY ON TUESDAY. -KT
LONG TERM...
(TUESDAY NIGHT-MONDAY)
.TIMING AND LOCATION OF UPPER LEVEL STORM LIFTING OUT ACROSS THE
SE PLAINS TUESDAY NIGHT THE MAIN FORECAST PROBLEM...
TUESDAY NIGHT-WEDNESDAY...SLIGHT MODEL DIFFERENCES ON TIMING AND
LOCATION OF UPPER LOW LIFTING OUT ACROSS THE SE PLAINS CONTINUE AND
HAVE TAILORED FORECAST TOWARDS THE NAM AND EC WHICH HAVE THE LOW
ACROSS EXTREME NORTHEAST NEW MEXICO AT 00Z WED AND THEN SLOWLY LIFT
IT OUT ACROSS WESTERN OKLAHOMA INTO CENTRAL OKLAHOMA THROUGH THE DAY
ON WEDNESDAY. ONGOING WRAP AROUND PRECIPITATION ACROSS THE EASTERN
MTS AND I-25 CORRIDOR TUESDAY AFTERNOON SLOWLY SHIFTS EAST AND
DIMINISHES FROM WEST TO EAST OVERNIGHT...AS UPPER LEVEL FLOW BECOMES
MORE NORTHWEST. COULD SEE SOME ADDITIONAL LIGHT ACCUMULATIONS OF A
COUPLE OF INCHES ACROSS THE NORTH AND EAST FACING SLOPES OF THE
EASTERN MTS AND ALONG WITH PALMER DVD AND RATON MESA TUESDAY EVENING
WITH THINGS WINDING INTO WEDNESDAY MORNING. TEMPERATURES ALOFT WARM
FROM WEST TO EAST THROUGH THE DAY ON WEDNESDAY...AS UPPER LEVEL
RIDGING BUILDS INTO THE STATE WITH HIGHS WARMING BACK TO AT OR
SLIGHTLY ABOVE SEASONAL AVERAGES...THOUGH HAVE TAPERED BACK HIGHS A
TAD IN EXPECTED SNOW COVERED AREAS.
WEDNESDAY NIGHT-MONDAY...WARMER AND DRIER WEATHER CONTINUES TO BE
PROGGED THROUGH THE PERIOD...WITH MODERATE TO STRONG WESTERLY FLOW
EXPECTED ACROSS THE REGION AS SEVERAL SHORT WAVES MOVE ACROSS THE
NORTHERN ROCKIES. ONE WAVE MOVES ACROSS THE REGION THURSDAY NIGHT
AND FRIDAY...WITH BREEZY TO WINDY CONDITIONS AND POSSIBLE CRITICAL
FIRE WEATHER CONDITIONS ON FRIDAY...DEPENDING ON HOW MUCH PRECIP
FALLS. PASSING WAVE SENDS A DRY COLD FRONT ACROSS THE PLAINS FRIDAY
WITH SLIGHTLY COOLER TEMPERATURES ACROSS THE AREA ON SATURDAY.
ANOTHER WAVE POSSIBLE MOVES ACROSS THE NORTHERN ROCKIES ON SUNDAY
NIGHT...WITH A BACKDOOR COLD FRONT POSSIBLE BRINGING IN ENOUGH LOW
LEVEL MOISTURE FOR A FEW SHOWERS ACROSS THE EASTERN PLAINS ON
MONDAY. HOWEVER...WILL KEEP A DRY FORECAST IN TACT THROUGH THE
PERIOD. -MW
AVIATION...
IFR CIGS/VIS EXPECTED TO AFFECT THE TAF SITES TONIGHT AS STRONG
SYSTEM MOVES ACROSS NORTHERN NEW MEXICO. STRONG NORTH WINDS IN THE
30 TO 45 KT RANGE WILL CONTINUE AT KCOS AND KPUB BEFORE DECREASING
TOWARDS 06Z. KALS WILL CONTINUE TO SEE EAST WINDS IN THE 25 TO 40
KT RANGE THROUGH EARLY EVENING WITH PERIODS OF BLDU. HEAVIEST SNOW
WILL IMPACT KCOS AND KPUB BETWEEN 06Z-18Z PERIOD WITH POTENTIAL FOR
A COUPLE INCHES OF SNOW...MAINLY ON GRASSY SURFACES AT KPUB...TO
AROUND 2 TO 5 INCHES AT KCOS. WITH WARM GROUND...THERE WILL BE SOME
MELTING AT TIMES AT KCOS...BUT PAVED SURFACES COULD BECOME SLUSHY
AND SNOWPACKED UNDER THE HEAVIER SNOW BANDS. KALS COULD SEE AN INCH
OR TWO AS WELL. RAIN/SNOW SWITCH OVER WILL OCCUR AROUND 03Z FOR
KCOS AND KALS...AND AROUND 06Z FOR KPUB. -KT
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WARNING UNTIL 6 PM MDT TUESDAY FOR COZ072>075-
078>082-084-087-088.
WINTER WEATHER ADVISORY UNTIL 6 PM MDT TUESDAY FOR COZ058-
060>063-066>068-076-077.
WINTER WEATHER ADVISORY UNTIL NOON MDT TUESDAY FOR COZ083-085-
086.
&&
$$
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
119 AM EDT TUE APR 3 2012
.PREV DISCUSSION... /ISSUED 745 PM EDT MON APR 2 2012/
.AVIATION.../06Z TAFS/
STLT/OBS SHOWING LOW/MID CLOUDS FORMING OVER THE WRN GRTLKS
REGION IN RESPONSE TO STRONG LOW LEVEL WAA PER LOCAL
PROFILERS/WVP. MODELS CONT TO SUGGEST ELEVATED CONVECTION WILL
DEVELOP IN THIS AREA 09-12Z AND SHIFT EAST OF THE AREA BY 15Z.
COVERAGE AND EXACT LOCATION STILL UNCERTAIN SO ONLY CARRIED VCTS
IN TERMINALS DURING THE EARLY MORNING HOURS. REMAINDER OF THE DAY
SHOULD HAVE VFR CONDITIONS WITH JUST SCT CU. SLIGHT CHC OF TS
DVLPG ALONG A CDFNT DROPPING SOUTH ACROSS THE AREA THIS AFTN/EVE
BUT WITH CAPPING INVERSION IN PLACE AND WK FORCING TS CHANCES AT
TERMINALS TOO LOW TO MENTION ATTM. CDFNT EXPECTED TO MOVE THROUGH
SBN AROUND 21Z AND FWA BY 00Z SHIFTING WINDS FROM SW TO NORTH
FOLLOWED BY PERIOD OF LOW VFR STRATO CU CIGS.
&&
.PREV DISCUSSION...
SHORT TERM...TONIGHT THROUGH TUESDAY NIGHT
CHANCES OF MORE THUNDERSTORMS LATE TONIGHT THROUGH TUESDAY EVENING
AND WARMER TEMPERATURES FOR TUESDAY WILL BE THE MAIN SHORT TERM
CONCERNS.
FOR TONIGHT...MOSTLY CLEAR SKIES EXPECTED ACROSS MUCH OF THE AREA
THIS EVENING WITH SOME INCREASING IN MID LEVEL CLOUDINESS WITH MID
LEVEL FRONTAL ZONE EXTENDING FROM NORTHERN LOWER MICHIGAN INTO
NORTHWEST OHIO. SOME LOWER BASED CLOUDS HAVE ALSO BEEN DEVELOPING
ALONG A LINE FROM NORTHWEST ILLINOIS INTO WEST CENTRAL ILLINOIS
WHICH SEEM TO CORRELATE WELL WITH RUC 900/850 HPA LAYER
FRONTOGENESIS FIELDS THIS AFTERNOON. THIS AXIS WILL GRADUALLY SHIFT
EASTWARD LATER THIS EVENING WITH INCREASE IN CLOUDINESS LATER THIS
EVENING FROM WEST TO EAST. WATER VAPOR IMAGERY NOT DEPICTING ANY
IMMEDIATE SHORT WAVES OF CONSEQUENCE FOR THE LOCAL AREA TONIGHT BUT
CONSISTENT SIGNAL OVER THE PAST FEW DAYS HAS BEEN FOR DEVELOPMENT OF
30 KNOT SOUTHWESTERLY LOW LEVEL JET NOSING INTO FAR NORTH CENTRAL
INDIANA/SOUTHERN LOWER MICHIGAN...PERHAPS A BIT MORE DELAYED IN THE
LAST FEW MODEL CYCLES. SEE LITTLE TO DEVIATE FROM PREVIOUS FORECAST
FOR TONIGHT AT THIS POINT WITH MID CHANCE POPS NORTH AND LOW CHANCE
POPS SOUTH...WITH THE HIGHER TSRA POPS LINING UP BETTER WITH 850 HPA
MOISTURE CONVERGENCE ACROSS SOUTHERN LOWER MICHIGAN AND FAR NORTHERN
INDIANA AFTER 06Z AS STRONG LOW LEVEL THETAE ADVECTION SPREADS FROM
WEST TO EAST.
ELEVATED MIXED LAYER ADVECTING INTO THE AREA LATER TONIGHT DOES POSE
SOME UNCERTAINTY WITH MAGNITUDE OF ELEVATED INSTABILITY. TAKING A
900 HPA BASED PARCEL FROM 12Z NAM BUFFER SOUNDINGS YIELDS BETWEEN
1000-1500 J/KG OF ELEVATED CAPE AFTER 06Z. 12Z GFS BUFFER SOUNDINGS
REMAIN A BIT MORE PRONOUNCED WITH THIS ELEVATED MIXED LAYER AND MID
LEVEL WARM LAYER THAT WOULD RESULT IN LESSER INSTABILITY THAN
INDICATED BY THE NAM. EFFECTIVE SHEAR FOR THESE ELEVATED PARCELS
SHOULD DECREASE STEADILY OVERNIGHT HOWEVER WHICH SHOULD TEND TO
LIMIT POTENTIAL FOR CONVECTIVE ORGANIZATION/SEVERE THREAT. PREVIOUS
FORECAST IDEA OF ISOLATED LARGE HAIL THREAT STILL SEEMS IN
ORDER...BUT SHIFTED A BIT LATER AFTER 06Z BASED ON TREND OF SLIGHTLY
SLOWER MODEL DEPICTION OF LOW LEVEL JET AXIS SHIFTING INTO THE AREA.
LINGERING ELEVATED CONVECTION SHOULD DIMINISH EARLY TUESDAY AS LOW
LEVEL JET VEERS AND MOISTURE CONVERGENCE WEAKENS. A CONVECTIVELY
ENHANCED VORT MAX ACROSS EASTERN TEXAS THIS AFTERNOON SHOULD LIFT
NORTHWARD INTO MID MS RVR VALLEY LATE TUESDAY AFTERNOON...BUT
OVERALL CONVECTIVE THREAT APPEARS TO BE LOW FOR LATE
MORNING/AFTERNOON HOURS WITH FCST SOUNDINGS SUGGEST SOME CAPPING
CONCERNS. THUS...HAVE LOWERED AFTERNOON TSRA POPS AND MAINTAINED
HIGHEST CHANCE ACROSS THE WEST WHERE FORCING FROM THIS VORT MAX WILL
LIKELY BE MAXIMIZED. BEST CHANCE OF SHOWERS AND THUNDERSTORMS LOOKS
TO BE FOR THE EVENING HOURS AS ANOTHER SOUTHERN CANADIAN UPPER LEVEL
SHORT WAVE PROVIDES IMPETUS FOR SFC LOW/FRONT TO SHIFT SOUTHEAST
THROUGH THE AREA. LOW LEVEL FRONTOGENESIS ALSO TO STRENGTHEN AS
STRONGER NORTHERLY FLOW INTERACTS WITH THIS BOUNDARY DURING THE
EARLY EVENING. SEVERE POTENTIAL APPEARS TO BE RELATIVELY LOW AT THIS
TIME DUE TO CONTINUED MARGINAL TO WEAK SHEAR PROFILES. HAVE ALSO
INCREASED MAX TEMPS FOR TUESDAY WITH CONFIDENCE INCREASING THAT MOST
IF NOT ALL OF FORECAST AREA WILL GET INTO WARM SECTOR AGAIN BEFORE
FRONTAL PASSAGE IN THE FAR NORTHWEST MID TO LATE AFTERNOON. RECORD
HIGHS IN THE UPPER 70S FOR FORT WAYNE AND SOUTH BEND COULD ONCE
AGAIN BE AT RISK OF BEING BROKEN.
LONG TERM...
WEDNESDAY THROUGH MONDAY
MAIN FOCUS OF LONG TERM PERIOD IS COOLER TEMPERATURES AND FROST
POTENTIAL WEDNESDAY NIGHT THROUGH FRIDAY NIGHT.
LONG TERM PERIOD BEGINS WEDNESDAY WITH SURFACE HIGH PRESSURE
CENTERED NORTHWEST OF THE REGION BUILDING SOUTHEASTWARD INTO THE
LOWER GREAT LAKES...AND A FRONTAL BOUNDARY SITUATED ALONG THE OHIO
RIVER VALLEY. CUTOFF UPPER LOW OVER PANHANDLE REGION WILL SLOWLY
TRACK EASTWARD TOWARDS MID MISSISSIPPI VALLEY. DRY CONDITIONS ARE
EXPECTED WEDNESDAY AND WEDNESDAY NIGHT. KEPT PATCHY FROST MENTION IN
THE NE PORTION OF THE FA...BUT INCREASED GRADIENT OF LOW TEMPS FROM
NE TO SW AS CUTOFF LOW AND AFOREMENTIONED BOUNDARY PASS JUST SOUTH
OF THE FA.
CUTOFF LOW WILL CONTINUE EASTWARD INTO LOWER OHIO VALLEY ON
THURSDAY. 12Z GFS INDICATED PRECIP POTENTIAL ACROSS THE FAR SW
PORTIONS OF THE FA AS FRONTAL BOUNDARY SLIDES EASTWARD.
HOWEVER...CONFIDENCE IS LOW AS 12Z GFS RUN OPENS LOW INTO POSITIVELY
TILTED WAVE QUICKER AND DIVES MORE SOUTHEASTERLY THAN PREVIOUS
RUN...MORE IN LINE WITH 00Z ECMWF. THURSDAY NIGHT LOOKS TO BE THE
COOLEST NIGHT IN THE EXTENDED PERIOD AS SFC RIDGE AXIS SLIDES
OVERHEAD. KEPT THE AREAS OF FROST MENTION IN ROUGHLY THE SAME AREAS
AS PREVIOUS FCST. WILL CONTINUE TO MONITOR THIS PD OVER THE NEXT FEW
FORECASTS WITH POSSIBLE NEED FOR HEADLINES...WITH LOWS NEARING 32-33
ACROSS MUCH OF THE FA.
SFC RIDGE WILL CONTINUE TO SLIDE EAST ACROSS GREAT LAKES AS UPPER
RIDGE AXIS MOVES ACROSS THE REGION. FRIDAY WILL AGAIN BE COOLER WITH
EASTERLY WINDS AND SLOWLY MODERATING AIRMASS. KEPT PATCHY FROST
MENTION IN FCST FRI NIGHT AS RIDGE AXIS WILL BE JUST EAST OF FA AND
LIGHTER WINDS. SATURDAY WILL BE CONSIDERABLY WARM WITH UPPER RIDGE
OVER THE AREA AND SFC HIGH EAST...RESULTING IN SOUTHERLY WINDS AND
WAA. RAISED TEMPS A FEW DEGREES FROM PREVIOUS FCST/ALLBLEND.
NEXT PRECIP CHANCES RETURN SAT NIGHT/SUN AS DEEPENING SFC
LOW/EJECTING WRN CONUS TROF ENERGY ACROSS NRN TIER BRINGS A COLD
FRONT THROUGH THE REGION. KEPT POPS CHANCE/SLIGHT CHANCE AS BEST
FORCING REMAINS NORTH AND BEST MOISTURE/INSTABILITY REMAINS SOUTH.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...NONE.
&&
$$
SHORT TERM...MARSILI
LONG TERM...NG
AVIATION...JT
AREA FORECAST DISCUSSION
NWS GOODLAND KS
418 AM MDT TUE APR 3 2012
.SHORT TERM...(TODAY THROUGH THURSDAY NIGHT)
ISSUED AT 418 AM MDT TUE APR 3 2012
FORECAST PROBLEMS WILL BE PRECIPITATION COVERAGE...AMOUNTS AND EVEN
PHASE AS LONG AS UPPER LOW IS IN THE AREA. SATELLITE SHOWING AN
AMPLIFIED PATTERN OVER THE NORTHERN HEMISPHERE. MAIN FEATURE OF
INTEREST IS UPPER LOW CURRENTLY SPINNING OVER EASTERN NEW MEXICO.
PATH AND SPEED OF THIS SYSTEM WILL AFFECT THE FORECAST.
THE ECMWF AND GFS WERE DOING BEST ON THE JET WINDS IN THE AREA
ASSOCIATED WITH THE UPPER LOW. THE ECMWF AND GFS WERE DOING A
LITTLE BETTER THAN THE CANADIAN ON THE POSITION OF THE UPPER LOW AND
ASSOCIATED HEIGHT FIELD IN THIS PORTION OF THE COUNTRY. THE NAM AND
ECMWF WERE DOING THE BEST ON THE SURFACE FIELD. ON THE LOW LEVEL
THERMAL FIELD...THE GFS WAS DOING THE BEST AND A LITTLE BETTER THAN
THE NAM. THE OTHER MODELS TENDED TO BE TOO WARM WITH THE NAM IN
SOME PLACES SLIGHTLY COOL.
TODAY/TONIGHT...RIGHT REAR QUADRANT STARTS OUT OVER THE AREA THIS
MORNING. THROUGH THE REST OF THE DAY...THE BEST JET LIFT REMAINS TO
THE SOUTH AND WEST OF THE AREA. ALSO CURRENT SHORTWAVE TROUGH WILL
MOVE THROUGH THIS MORNING BEFORE DRY SLOT ENTERS THE AREA. CURRENT
GRIDS CAPTURE AREA OF GREATEST CHANCE OF PRECIPITATION. THIS AREA
IS ALSO MATCHING UP WITH THE SREF QPF. DUE TO SOME EMBEDDED
CONVECTION AND INTENSE RAINFALL RATES...SOME AREAS IN EASTERN
COLORADO ARE RECEIVING SNOW AT THIS TIME WITH THE MOST INTENSE
PRECIPITATION. KITR IS RECEIVING SNOW AT THIS TIME. WILL CONTINUE
TO WATCH THE TRENDS ON THE PRECIPITATION/TEMPERATURES AND PUT IN A
RAIN OR RAIN AND SNOW MIX. BASED ON WHAT IS GOING AT THIS TIME AND
MODELS INDICATING ELEVATED INSTABILITY...WILL BE INSERTING SOME
ISOLATED TRW-.
MODELS ARE COMING IN TO BETTER AGREEMENT AND HAVE THE MID LEVEL
CIRCULATION IN A VERY FAVORABLE LOCATION FOR WIDESPREAD
PRECIPITATION THIS AFTERNOON INTO TONIGHT. DEEP UPSLOPE/MOISTURE
ALONG WITH STRONG SYNOPTIC SCALE/MESOSCALE FORCING AND ISENTROPIC
LIFT ARE ALL SHOWN BY THE MODELS. BASED ON THE PREVIOUS REASONING
LIKE THE HIGH MODEL QPFS GENERATED...HOWEVER WITH BULLSEYES IN
DIFFERENT PLACES. SREF/HPC PQPF SHOW A GREATER THAN 50 PERCENT
CHANCE OF MORE THAN AN INCH ACCUMULATION OF LIQUID ON VARIOUS TIME
SCALES. AS A RESULT WENT WITH MODERATE RAINFALL...AND CONTINUED
EMBEDDED CONVECTION DUE TO THE ELEVATED INSTABILITY...AND WITH THE
HPC QPF WHICH IS IN CLOSE AGREEMENT TO THE ECMWF SOLUTION WHICH BASED
ON THE MAJORITY OF MODEL OUTPUT...CONSISTENCY...AND CURRENT FLOW
PATTERN LOOKS VERY REASONABLE.
MODELS KEEP UPSLOPE FLOW OR LOW LEVEL ISENTROPIC LIFT IN PLACE
THROUGH THE DAY ALONG WITH OFF AND ON PRECIPITATION. SO SEE NO CHANCE
TO WARM VERY MUCH. WILL ADJUST FINAL MAXES AS SEE HOW FAR CURRENT
MINS DROP.
WEDNESDAY/WEDNESDAY NIGHT...AS STATED ABOVE...LIKE THE ECMWF
SOLUTION. IT IS SLOWER THAN EVERYTHING ELSE AND MAKES SENSE.
HOWEVER IT MAY NOT BE FAR ENOUGH NORTH AS IT KICKS OUT DUE TO THE
STRONG DOWNSTREAM RIDGE. SO PRECIPITATION WILL BE SLOWER TO END AND
CLOUD COVER WILL ALSO HANG AROUND LONGER. WILL ADJUST MAXES LOWER
AND PRECIPITATION HIGHER BASED ON THIS WITH PRECIPITATION CHANCES
HIGHER AND LASTING LONGER IN THE EAST.
MODELS CLEAR EVERYTHING OUT BY LATER IN THE NIGHT. WIND FIELD WILL
BE LIGHT WITH LEFTOVER MOIST LOW LEVEL AIR MASS AND MOIST GROUND
OVER A LARGE AREA. MORE THAN ONE MODEL GENERATES FOG AND WILL INSERT
IT IN...MAINLY AFTER 06Z.
THURSDAY/THURSDAY NIGHT...WILL CONTINUE THE FOG IN THE MORNING.
LOW CLOUDS AND FOG IN THE MORNING COMBINED WITH LIGHT AND VARIABLE
WINDS OR UPSLOPE WINDS WILL KEEP TEMPERATURES FROM RISING TOO MUCH.
IN FACT WHAT IS IN THERE MAY END UP BEING TOO WARM AND THIS WILL
NEED TO BE LOOKED AT AGAIN.
DO NOT EXPECT THE LOW LEVEL AIR MASS TO DRY OUT MUCH DUE TO THE
EXPECTED WIDE SPREAD PRECIPITATION THAT HAS JUST ENDED. ALSO MODELS
INCREASE SOUTH TO SOUTHEAST LOW LEVEL FLOW WHICH DRAWS IN EVEN MORE
MOISTURE OR KEEPS IT HERE. AT THE VERY LEAST SHOULD BE WIDESPREAD
STRATUS BUT ALSO PROBABLY ANOTHER ROUND OF FOG.
THANKS TO ALL THAT COLLABORATED.
.LONG TERM...(FRIDAY THROUGH MONDAY)
ISSUED AT 418 AM MDT TUE APR 3 2012
MID/UPPER TROUGH WILL REMAIN TO OUR WEST/NORTHWEST EARLY FRIDAY BUT
A LEAD SHORTWAVE TROUGH IS PROGGED TO TRANSLATE ACROSS THE REGION
DURING THE DAY. WILL MAINTAIN INHERITED SLIGHT CHANCE POPS OVER THE
EASTERN THIRD. PRECIP MAY LINGER INTO SATURDAY MORNING BEFORE
SUBSIDENCE OVERTAKES THE REGION BEHIND A SURFACE COLD FRONT. STRONG
SOUTHERLY FLOW AHEAD OF THE TROUGH WILL ALLOW TEMPS ON FRIDAY TO
WARM INTO THE UPPER 60S TO LOWER 70S ACROSS THE REGION.
A MUCH DRIER AIR MASS WILL FILTER INTO THE WESTERN HALF OF THE
FORECAST AREA ON SATURDAY WHICH COULD RESULT IN A CRITICAL FIRE
WEATHER DAY. CURRENT WIND SPEEDS ARE PROGGED TO BE BORDERLINE. THE
OVERALL THREAT FOR CRITICAL FIRE WEATHER WILL LIKELY BE MITIGATED TO
SOME EXTENT BY THE WIDESPREAD MOISTURE EXPECTED TO IMPACT THE REGION
OVER THE NEXT 36 HOURS.
QUASI-ZONAL FLOW SETS UP ON SUNDAY BEFORE SHIFTING TO MORE
NORTHWESTERLY FLOW ALOFT IN RESPONSE TO A BUILDING RIDGE ACROSS THE
GREAT BASIN/INTERMOUNTAIN WEST. SERIES OF WEAK SHORTWAVE TROUGHS
WILL PASS THROUGH THE AREA KEEPING TEMPS SEASONABLE. LIMITED
AVAILABLE MOISTURE WILL LIKELY PRECLUDE THE DEVELOPMENT OF
WIDESPREAD PRECIPITATION.
&&
.AVIATION...FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1032 PM MDT MON APR 2 2012
RUC IS HANDLING THE CLOUDS FAIRLY WELL SO HAVE USED THIS MODEL AS
WELL AS THE HRRR CONCERNING THE PRECIPITATION. MVFR CIGS AT BOTH
KGLD AND KMCK TO CONTINUE THROUGH THE NEXT 24 HOURS. BAND OF
PRECIPITATION WILL IMPACT BOTH TERMINALS AT THE BEGINNING OF THE TAF
PERIOD AND CONTINUE THROUGH 10Z-11Z BEFORE ROTATING OUT OF THE AREA
AS MID LEVEL DRY SLOT MOVES IN. THERE IS A CHANCE FOR SEVERAL HOURS
OF IFR CONDITIONS AT BOTH TERMINALS TIL 16Z OR SO WHEN ANOTHER BATCH
OF PRECIP MOVES NORTH IMPACTING KGLD AROUND 16Z AND KMCK AROUND
00Z. THIS BATCH OF PRECIP SHOULD CONTINUE THROUGH THE REMAINDER OF
THE TAF PERIOD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
KS...NONE.
NE...NONE.
&&
$$
SHORT TERM...BULLER
LONG TERM....FOLTZ
AVIATION...BAS/DDT
AREA FORECAST DISCUSSION
NWS GOODLAND KS
140 AM MDT TUE APR 3 2012
.UPDATE...
ISSUED AT 139 AM MDT TUE APR 3 2012
JUST COMPLETED A QUICK UPDATE. GETTING REPORTS OF SNOW...UP TO AN
INCH...A LITTLE FARTHER EAST THAT WAS CURRENTLY CALLED FOR THROUGH
THE REST OF THIS EARLY MORNING. SO JUST EXPANDED THAT AREA.
UPDATE ISSUED AT 928 PM MDT MON APR 2 2012
AT 0330Z RAIN CONTINUES TO MOVE NORTHWEST AROUND 25 MPH IN
RESPONSE TO LOW PRESSURE SPINNING ACROSS EAST CENTRAL NEW MEXICO.
NORTH TO NORTHEAST WINDS CONTINUE TO GUST AROUND 40 MPH.
FOR TONIGHT ALLOWED WIND ADVISORY TO EXPIRE. WIND GUSTS IN EXCESS
OF 45 MPH ARE NO LONGER EXPECTED.
FORECAST CHALLENGE FOR THE NEXT 20 HOUR OR SO IS PLACEMENT OF THE
HIGHEST POPS/QPF AND SNOW.
GENERALLY THINKING IS FOR CURRENT BAND OF PRECIPITATION TO MOVE
NORTHWEST THROUGH THE FORECAST AREA DURING THE REMAINDER OF THE
NIGHT WITH SOME DRIER MID LEVEL AIR CURRENTLY OVER THE TEXAS
PANHANDLE TO QUICKLY MOVE NORTH BRINGING AN END TO THE HEAVIER
PRECIPITATION (EXCEPT THE NORTHWEST 1/4 OF THE AREA) BY SUNRISE.
FLAGLER CURRENT TEMP IS 37...NAM AND TO A LESSER EXTENT RUC LOWER
TEMPERATURES INTO THE LOWER 30S BY SUNRISE WHICH WOULD SUPPORT
SNOW VS ANY MIX OF RAIN AND SNOW. HOW FAR EAST THESE COLDER
TEMPERATURES GET IS THE BIG QUESTION AS THE NAM PUSHES THEM AS FAR
EAST AS THE CO/KS BORDER WHILE THE HRRR IS SLIGHTLY FURTHER WEST
AND THE SREF FURTHER WEST TOWARD SEIBERT. RIGHT NOW ONLY HAVE SNOW
ACCUMULATIONS OF A FEW INCHES CONFINED TO THE FLAGLER AREA AND
MIDNIGHT SHIFT WILL NEED TO MONITOR JUST HOW FAR EAST THE COLDER
TEMPERATURES GET. GIVEN THE EXPECTED PRECIPITATION SEVERAL INCHES
OF ACCUMULATION IS CERTAINLY POSSIBLE. HAVE UPDATED HWO TO MENTION
THE ACCUMULATION POSSIBILITIES.
FOR TUESDAY LOWERED TEMPERATURES ACROSS THE ENTIRE AREA AS WE WILL
BE UNDER EXTENSIVE CLOUD COVER. 00Z NAM/21Z SREF/00Z MET AND 18Z
MAV 3 HOUR TEMPERATURES ALL IN PRETTY GOOD AGREEMENT WITH HIGHS
RANGING FROM THE MID 30S TO LOW 40S ACROSS FAR EASTERN COLORADO TO
THE MID 40S AND LOW 50S EAST OF THE BORDER.
SHOULD HAVE ANOTHER BATCH OF RAIN MOVING IN FROM THE SOUTH DURING
THE DAY WITH HIGHEST AMOUNTS GENERALLY SOUTH OF A LINE FROM YUMA
TO COLBY AND GOVE.
UPDATE ISSUED AT 541 PM MDT MON APR 2 2012
LINE OF SHOWERS AND THUNDERSTORMS JUST EAST-SOUTHEAST OF THE
FORECAST AREA MOVING NORTHWEST AT 20-25 MPH. THIS WILL PUT THEM
INTO THE SOUTHEAST PORTION OF THE AREA BY 01Z IF NOT A LITTLE SOONER.
ALTHOUGH INSTABILITY REMAINS HIGHER TO THE SOUTHEAST OF OUR AREA
CANT RULE OUT A FEW LIGHTNING STRIKES SO UPDATED TO INCLUDE SOME
THUNDER MENTION.
OTHER CHANGES WERE TO BEEF UP THE CLOUDINESS TONIGHT THROUGH
TUESDAY AS LOW LEVEL MOISTURE AND CLOUDS COVER THE FORECAST AREA.
OTHER CHANGES TO BE MADE LATER AS 00Z MODEL DATA COMES IN.
&&
.SHORT TERM...(TONIGHT THROUGH TUESDAY)
ISSUED AT 221 PM MDT MON APR 2 2012
PLAN TO LET THE WIND ADVISORY GO TO EXPIRATION AT 03Z. THIS SHOULD
WORK OUT WELL SINCE HAVE ALREADY STARTED TO DECREASE. THE NAM MIXED
LAYER WINDS INDICATE THAT THEY FALL AT OR JUST BELOW WIND ADVISORY
LEVELS AT 03Z. THE GFS MIXED LAYER WIND KEEPS IT WINDY OVER THE
SOUTHWEST THROUGH THE NIGHT. THIS IS PROBABLY AN OUTLIER SINCE THE
TREND FOR WINDS IN THAT PART OF THE AREA IS SIMILAR TO THE REST OF
THE FA. THE EVENING SHIFT WILL NEED TO DETERMINE WHETHER THE
ADVISORY SHOULD BE EXTENDED IN TIME.
THE UPPER LOW WILL MOVE NORTHEAST TONIGHT. THERE IS SOME UNCERTAINTY
AS TO HOW QUICKLY PRECIPITATION WILL MOVE NORTHWARD SINCE THE MODELS
DO NOT HAVE THE LOW AS FAR SOUTH AS ITS ACTUAL POSITION ON WATER
VAPOR IMAGERY. NEVERTHELESS HAVE INTRODUCED CHANCE POPS FOR THE
SOUTHERN ZONES THIS EVENING. BETTER CHANCES SHOULD TAKE PLACE AFTER
MIDNIGHT TONIGHT AS THE LOW HAS MORE TIME TO MOVE NORTH. FORECAST
SOUNDINGS INDICATE THAT TEMPERATURES WILL GET COLD ENOUGH FOR A FEW
HOURS AROUND SUNRISE IN EASTERN COLORADO FOR A MIX OF RAIN/SNOW. THE
NAM SHOWS A LULL IN THE PRECIPITATION TUESDAY MORNING WITH THE
PASSAGE OF THE INITIAL SHORTWAVE SO WILL KEEP CHANCE POPS IN PLACE
FOR TUESDAY MORNING. BY AFTERNOON THE NEXT WAVE IS PROGGED TO MOVE
THROUGH THE FA SO WILL INCREASE TO HIGH CHANCE.
LOW TEMPERATURES TONIGHT WILL GET DOWN TO 32 IN FAR WESTERN PORTIONS
OF THE FA. OTHERWISE TEMPERATURES WILL RANGE FROM THE MID 30S FROM
NEAR THE COLORADO BORDER TO THE LOWER 40S IN MCK AND HLC. MAX
TEMPERATURES WILL RANGE FROM THE UPPER 40S IN EASTERN COLORADO TO
THE MID 50S IN THE EASTERN FA.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 221 PM MDT MON APR 2 2012
MAIN FOCUS WILL CONTINUE TO BE THE CLOSED LOW AND PRECIP. CHANCES
THROUGH WEDNESDAY. MODELS ARE IN BETTER AGREEMENT WITH THE TRACK OF
THE CLOSED LOW AS IT MOVES NORTHEAST. NOTICED THE 0Z ECMWF AND
LATEST NAM/SREF ARE IN BETTER AGREEMENT THAN YESTERDAY. AS
MENTIONED ABOVE...AM CONCERNED THE MODELS DID NOT INITIALIZE THE
CLOSED LOW FAR ENOUGH SOUTH BASED MORNING WATER VAPOR
IMAGERY. WITH THE CLOSED LOW BEING FURTHER SOUTH THAN WHAT THE
MODELS HAVE...AM THINKING IT WILL LIFT FURTHER EAST THAN WHAT THE
NAM/SREF/ECMWF HAVE. AS SUCH WILL TRENDED HIGHER POPS FURTHER EAST
FOR TUESDAY NIGHT THROUGH WEDNESDAY BASED ON ABOVE CONCERNS.
TUESDAY NIGHT THE LEFT EXIT OF THE UPPER LEVEL JET MOVES OVER THE
EASTERN PART OF THE AREA AND ISENTROPIC LIFT INCREASES AS THE
CLOSED LOW APPROACHES. OVER THE NORTHERN HALF OF THE AREA DEEP
LIFTING SETS UP AND A BAND OF FRONTOGENESIS DEVELOPS. AS THE CLOSED
LOW MOVES EAST THROUGH THE NIGHT THE LIFT FOLLOWS. TRENDED POPS IN
THE SAME DIRECTION...WITH THE BEST CHANCES GENERALLY OVER THE EASTERN
PART OF THE AREA WHERE THE BEST LIFT AND HIGHEST CERTAINTY WILL
BE WITH LOWER CHANCES TO THE WEST WHERE THE I AM MORE UNCERTAIN
THAT THE LIFT WILL DEVELOP BE AS THE SYSTEM MOVES EAST. AREAS OF
EASTERN COLORADO MAY SEE A MIX OF RAIN AND SNOW AS TEMPERATURES
DIP TO THE FREEZING POINT. NAM POINT SOUNDINGS SUGGEST A WINDOW OF
FREEZING DRIZZLE DURING THE OVERNIGHT AND EARLY MORNING HOURS.
HOWEVER SREF PRECIP. TYPE FIELDS ONLY SHOW A MIX OF RAIN AND SNOW.
WILL JUST MENTION THE RAIN/SNOW MIX THROUGH THE NIGHT AND EARLY
MORNING HOURS DUE TO UNCERTAINTY OF THE TRACK OF THE STORM SYSTEM.
WEDNESDAY ISENTROPIC LIFT DWINDLES TOWARD THE WEST AS THE CLOSED LOW
DEPARTS. HAVE PRECIP. CHANCES HIGHEST IN THE EAST WHERE THE FORCING
FOR LIFT IS BEST WITH CHANCES DECLINING TO THE WEST. THROUGH THE
DAY PRECIP. CHANCES DECLINE ACROSS THE AREA AS THE CLOSED LOW
MOVES FURTHER EAST...WITH THE PRECIP. CHANCES COMING TO AN END
OVER THE FAR EAST BY EARLY EVENING.
FOR THURSDAY THROUGH MONDAY AN UPPER LEVEL SHORT WAVE RIDGE MOVES
OVER THE AREA THURSDAY BEHIND THE EXITING STORM SYSTEM. BY
THURSDAY NIGHT THE UPPER LEVEL FLOW TURNS TO THE NORTHWEST AHEAD OF
THE NEXT UPPER LEVEL TROUGH MOVING ACROSS THE INTER MOUNTAIN WEST.
PRECIPITATION CHANCES RETURN TO THE EASTERN PART OF THE AREA
THURSDAY NIGHT THROUGH FRIDAY NIGHT AS A COUPLE UPPER LEVEL SHORT
WAVE TROUGHS MOVE OVER THE AREA. WITH THE LOW LEVEL JET AND
ISENTROPIC LIFT AHEAD OF THE TROUGHS...A FEW SHOWERS AND/OR
THUNDERSTORMS WILL BE POSSIBLE OVER THE EASTERN PART OF THE AREA.
TEMPERATURES WILL BE ABOVE NORMAL THROUGH THE PERIOD...WITH A
WARMING TREND THURSDAY AND FRIDAY. COOLER BUT ABOVE NORMAL
TEMPERATURES RETURN THROUGH THE REST OF THE PERIOD BEHIND A COLD
FRONT THAT MOVES THROUGH FRIDAY NIGHT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1032 PM MDT MON APR 2 2012
RUC IS HANDLING THE CLOUDS FAIRLY WELL SO HAVE USED THIS MODEL AS
WELL AS THE HRRR CONCERNING THE PRECIPITATION. MVFR CIGS AT BOTH
KGLD AND KMCK TO CONTINUE THROUGH THE NEXT 24 HOURS. BAND OF PRECIPITATION
WILL IMPACT BOTH TERMINALS AT THE BEGINNING OF THE TAF PERIOD AND
CONTINUE THROUGH 10Z-11Z BEFORE ROTATING OUT OF THE AREA AS MID
LEVEL DRY SLOT MOVES IN. THERE IS A CHANCE FOR SEVERAL HOURS OF
IFR CONDITIONS AT BOTH TERMINALS TIL 16Z OR SO WHEN ANOTHER BATCH
OF PRECIP MOVES NORTH IMPACTING KGLD AROUND 16Z AND KMCK AROUND
00Z. THIS BATCH OF PRECIP SHOULD CONTINUE THROUGH THE REMAINDER OF
THE TAF PERIOD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
KS...NONE.
NE...NONE.
&&
$$
UPDATE...BULLER
SHORT TERM...FS
LONG TERM....JTL
AVIATION...BAS/DDT
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1040 PM MDT MON APR 2 2012
.UPDATE...
ISSUED AT 928 PM MDT MON APR 2 2012
AT 0330Z RAIN CONTINUES TO MOVE NORTHWEST AROUND 25 MPH IN
RESPONSE TO LOW PRESSURE SPINNING ACROSS EAST CENTRAL NEW MEXICO.
NORTH TO NORTHEAST WINDS CONTINUE TO GUST AROUND 40 MPH.
FOR TONIGHT ALLOWED WIND ADVISORY TO EXPIRE. WIND GUSTS IN EXCESS
OF 45 MPH ARE NO LONGER EXPECTED.
FORECAST CHALLENGE FOR THE NEXT 20 HOUR OR SO IS PLACEMENT OF THE
HIGHEST POPS/QPF AND SNOW.
GENERALLY THINKING IS FOR CURRENT BAND OF PRECIPITATION TO MOVE
NORTHWEST THROUGH THE FORECAST AREA DURING THE REMAINDER OF THE
NIGHT WITH SOME DRIER MID LEVEL AIR CURRENTLY OVER THE TEXAS
PANHANDLE TO QUICKLY MOVE NORTH BRINGING AN END TO THE HEAVIER
PRECIPITATION (EXCEPT THE NORTHWEST 1/4 OF THE AREA) BY SUNRISE.
FLAGLER CURRENT TEMP IS 37...NAM AND TO A LESSER EXTENT RUC LOWER
TEMPERATURES INTO THE LOWER 30S BY SUNRISE WHICH WOULD SUPPORT
SNOW VS ANY MIX OF RAIN AND SNOW. HOW FAR EAST THESE COLDER
TEMPERATURES GET IS THE BIG QUESTION AS THE NAM PUSHES THEM AS FAR
EAST AS THE CO/KS BORDER WHILE THE HRRR IS SLIGHTLY FURTHER WEST
AND THE SREF FURTHER WEST TOWARD SEIBERT. RIGHT NOW ONLY HAVE SNOW
ACCUMULATIONS OF A FEW INCHES CONFINED TO THE FLAGLER AREA AND
MIDNIGHT SHIFT WILL NEED TO MONITOR JUST HOW FAR EAST THE COLDER
TEMPERATURES GET. GIVEN THE EXPECTED PRECIPITATION SEVERAL INCHES
OF ACCUMULATION IS CERTAINLY POSSIBLE. HAVE UPDATED HWO TO MENTION
THE ACCUMULATION POSSIBILITIES.
FOR TUESDAY LOWERED TEMPERATURES ACROSS THE ENTIRE AREA AS WE WILL
BE UNDER EXTENSIVE CLOUD COVER. 00Z NAM/21Z SREF/00Z MET AND 18Z
MAV 3 HOUR TEMPERATURES ALL IN PRETTY GOOD AGREEMENT WITH HIGHS
RANGING FROM THE MID 30S TO LOW 40S ACROSS FAR EASTERN COLORADO TO
THE MID 40S AND LOW 50S EAST OF THE BORDER.
SHOULD HAVE ANOTHER BATCH OF RAIN MOVING IN FROM THE SOUTH DURING
THE DAY WITH HIGHEST AMOUNTS GENERALLY SOUTH OF A LINE FROM YUMA
TO COLBY AND GOVE.
UPDATE ISSUED AT 541 PM MDT MON APR 2 2012
LINE OF SHOWERS AND THUNDERSTORMS JUST EAST-SOUTHEAST OF THE
FORECAST AREA MOVING NORTHWEST AT 20-25 MPH. THIS WILL PUT THEM
INTO THE SOUTHEAST PORTION OF THE AREA BY 01Z IF NOT A LITTLE SOONER.
ALTHOUGH INSTABILITY REMAINS HIGHER TO THE SOUTHEAST OF OUR AREA
CANT RULE OUT A FEW LIGHTNING STRIKES SO UPDATED TO INCLUDE SOME
THUNDER MENTION.
OTHER CHANGES WERE TO BEEF UP THE CLOUDINESS TONIGHT THROUGH
TUESDAY AS LOW LEVEL MOISTURE AND CLOUDS COVER THE FORECAST AREA.
OTHER CHANGES TO BE MADE LATER AS 00Z MODEL DATA COMES IN.
&&
.SHORT TERM...(TONIGHT THROUGH TUESDAY)
ISSUED AT 221 PM MDT MON APR 2 2012
PLAN TO LET THE WIND ADVISORY GO TO EXPIRATION AT 03Z. THIS SHOULD
WORK OUT WELL SINCE HAVE ALREADY STARTED TO DECREASE. THE NAM MIXED
LAYER WINDS INDICATE THAT THEY FALL AT OR JUST BELOW WIND ADVISORY
LEVELS AT 03Z. THE GFS MIXED LAYER WIND KEEPS IT WINDY OVER THE
SOUTHWEST THROUGH THE NIGHT. THIS IS PROBABLY AN OUTLIER SINCE THE
TREND FOR WINDS IN THAT PART OF THE AREA IS SIMILAR TO THE REST OF
THE FA. THE EVENING SHIFT WILL NEED TO DETERMINE WHETHER THE
ADVISORY SHOULD BE EXTENDED IN TIME.
THE UPPER LOW WILL MOVE NORTHEAST TONIGHT. THERE IS SOME UNCERTAINTY
AS TO HOW QUICKLY PRECIPITATION WILL MOVE NORTHWARD SINCE THE MODELS
DO NOT HAVE THE LOW AS FAR SOUTH AS ITS ACTUAL POSITION ON WATER
VAPOR IMAGERY. NEVERTHELESS HAVE INTRODUCED CHANCE POPS FOR THE
SOUTHERN ZONES THIS EVENING. BETTER CHANCES SHOULD TAKE PLACE AFTER
MIDNIGHT TONIGHT AS THE LOW HAS MORE TIME TO MOVE NORTH. FORECAST
SOUNDINGS INDICATE THAT TEMPERATURES WILL GET COLD ENOUGH FOR A FEW
HOURS AROUND SUNRISE IN EASTERN COLORADO FOR A MIX OF RAIN/SNOW. THE
NAM SHOWS A LULL IN THE PRECIPITATION TUESDAY MORNING WITH THE
PASSAGE OF THE INITIAL SHORTWAVE SO WILL KEEP CHANCE POPS IN PLACE
FOR TUESDAY MORNING. BY AFTERNOON THE NEXT WAVE IS PROGGED TO MOVE
THROUGH THE FA SO WILL INCREASE TO HIGH CHANCE.
LOW TEMPERATURES TONIGHT WILL GET DOWN TO 32 IN FAR WESTERN PORTIONS
OF THE FA. OTHERWISE TEMPERATURES WILL RANGE FROM THE MID 30S FROM
NEAR THE COLORADO BORDER TO THE LOWER 40S IN MCK AND HLC. MAX
TEMPERATURES WILL RANGE FROM THE UPPER 40S IN EASTERN COLORADO TO
THE MID 50S IN THE EASTERN FA.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 221 PM MDT MON APR 2 2012
MAIN FOCUS WILL CONTINUE TO BE THE CLOSED LOW AND PRECIP. CHANCES
THROUGH WEDNESDAY. MODELS ARE IN BETTER AGREEMENT WITH THE TRACK OF
THE CLOSED LOW AS IT MOVES NORTHEAST. NOTICED THE 0Z ECMWF AND
LATEST NAM/SREF ARE IN BETTER AGREEMENT THAN YESTERDAY. AS
MENTIONED ABOVE...AM CONCERNED THE MODELS DID NOT INITIALIZE THE
CLOSED LOW FAR ENOUGH SOUTH BASED MORNING WATER VAPOR
IMAGERY. WITH THE CLOSED LOW BEING FURTHER SOUTH THAN WHAT THE
MODELS HAVE...AM THINKING IT WILL LIFT FURTHER EAST THAN WHAT THE
NAM/SREF/ECMWF HAVE. AS SUCH WILL TRENDED HIGHER POPS FURTHER EAST
FOR TUESDAY NIGHT THROUGH WEDNESDAY BASED ON ABOVE CONCERNS.
TUESDAY NIGHT THE LEFT EXIT OF THE UPPER LEVEL JET MOVES OVER THE
EASTERN PART OF THE AREA AND ISENTROPIC LIFT INCREASES AS THE
CLOSED LOW APPROACHES. OVER THE NORTHERN HALF OF THE AREA DEEP
LIFTING SETS UP AND A BAND OF FRONTOGENESIS DEVELOPS. AS THE CLOSED
LOW MOVES EAST THROUGH THE NIGHT THE LIFT FOLLOWS. TRENDED POPS IN
THE SAME DIRECTION...WITH THE BEST CHANCES GENERALLY OVER THE EASTERN
PART OF THE AREA WHERE THE BEST LIFT AND HIGHEST CERTAINTY WILL
BE WITH LOWER CHANCES TO THE WEST WHERE THE I AM MORE UNCERTAIN
THAT THE LIFT WILL DEVELOP BE AS THE SYSTEM MOVES EAST. AREAS OF
EASTERN COLORADO MAY SEE A MIX OF RAIN AND SNOW AS TEMPERATURES
DIP TO THE FREEZING POINT. NAM POINT SOUNDINGS SUGGEST A WINDOW OF
FREEZING DRIZZLE DURING THE OVERNIGHT AND EARLY MORNING HOURS.
HOWEVER SREF PRECIP. TYPE FIELDS ONLY SHOW A MIX OF RAIN AND SNOW.
WILL JUST MENTION THE RAIN/SNOW MIX THROUGH THE NIGHT AND EARLY
MORNING HOURS DUE TO UNCERTAINTY OF THE TRACK OF THE STORM SYSTEM.
WEDNESDAY ISENTROPIC LIFT DWINDLES TOWARD THE WEST AS THE CLOSED LOW
DEPARTS. HAVE PRECIP. CHANCES HIGHEST IN THE EAST WHERE THE FORCING
FOR LIFT IS BEST WITH CHANCES DECLINING TO THE WEST. THROUGH THE
DAY PRECIP. CHANCES DECLINE ACROSS THE AREA AS THE CLOSED LOW
MOVES FURTHER EAST...WITH THE PRECIP. CHANCES COMING TO AN END
OVER THE FAR EAST BY EARLY EVENING.
FOR THURSDAY THROUGH MONDAY AN UPPER LEVEL SHORT WAVE RIDGE MOVES
OVER THE AREA THURSDAY BEHIND THE EXITING STORM SYSTEM. BY
THURSDAY NIGHT THE UPPER LEVEL FLOW TURNS TO THE NORTHWEST AHEAD OF
THE NEXT UPPER LEVEL TROUGH MOVING ACROSS THE INTER MOUNTAIN WEST.
PRECIPITATION CHANCES RETURN TO THE EASTERN PART OF THE AREA
THURSDAY NIGHT THROUGH FRIDAY NIGHT AS A COUPLE UPPER LEVEL SHORT
WAVE TROUGHS MOVE OVER THE AREA. WITH THE LOW LEVEL JET AND
ISENTROPIC LIFT AHEAD OF THE TROUGHS...A FEW SHOWERS AND/OR
THUNDERSTORMS WILL BE POSSIBLE OVER THE EASTERN PART OF THE AREA.
TEMPERATURES WILL BE ABOVE NORMAL THROUGH THE PERIOD...WITH A
WARMING TREND THURSDAY AND FRIDAY. COOLER BUT ABOVE NORMAL
TEMPERATURES RETURN THROUGH THE REST OF THE PERIOD BEHIND A COLD
FRONT THAT MOVES THROUGH FRIDAY NIGHT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1032 PM MDT MON APR 2 2012
RUC IS HANDLING THE CLOUDS FAIRLY WELL SO HAVE USED THIS MODEL AS
WELL AS THE HRRR CONCERNING THE PRECIPITATION. MVFR CIGS AT BOTH
KGLD AND KMCK TO CONTINUE THROUGH THE NEXT 24 HOURS. BAND OF PRECIPITATION
WILL IMPACT BOTH TERMINALS AT THE BEGINNING OF THE TAF PERIOD AND
CONTINUE THROUGH 10Z-11Z BEFORE ROTATING OUT OF THE AREA AS MID
LEVEL DRY SLOT MOVES IN. THERE IS A CHANCE FOR SEVERAL HOURS OF
IFR CONDITIONS AT BOTH TERMINALS TIL 16Z OR SO WHEN ANOTHER BATCH
OF PRECIP MOVES NORTH IMPACTING KGLD AROUND 16Z AND KMCK AROUND
00Z. THIS BATCH OF PRECIP SHOULD CONTINUE THROUGH THE REMAINDER OF
THE TAF PERIOD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
KS...NONE.
NE...NONE.
&&
$$
UPDATE...007
SHORT TERM...FS
LONG TERM....JTL
AVIATION...BAS/DDT
AREA FORECAST DISCUSSION
NWS PADUCAH KY
700 PM CDT WED APR 4 2012
.UPDATE...
ISSUED AT 700 PM CDT WED APR 4 2012
REVISED AVIATION DISCUSSION FOR 00Z TAFS.
SHOWER AND THUNDERSTORM DEVELOPMENT REMAINS MOSTLY CONFINED TO THE
NORTHEAST QUARTER OF THE PAH FORECAST AREA AND A SMALL PORTION OF
SOUTHEAST MISSOURI...WITH ISOLATED CELLS IN EXTREME SOUTHERN
ILLINOIS. BOUNDARY IS MAKING VERY SLOW PROGRESSION SOUTH ACROSS THE
FA...BUT WITH LOSS OF DAYTIME HEATING...DO NOT EXPECT SHOWERS AND
STORMS TO BECOME ANY MORE WIDESPREAD FOR A WHILE. BACKED OFF POPS
CONSIDERABLY THIS EVENING ACROSS ALL BUT THE AFOREMENTIONED AREAS.
WENT WITH HIGH CHANCE POPS NORTH TO SLIGHT CHANCE POPS AFTER
MIDNIGHT...WITH RUC INDICATING SOME DECENT QPF ACROSS OUR NORTHERN
COUNTIES.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT)
ISSUED AT 232 PM CDT WED APR 4 2012
FINALLY...WITHIN THE LAST 30 MIN OR SO...IT LOOKS AS THOUGH MOST
OF THE AREA HAS RECEIVED ENOUGH SFC HEATING...AND THE SLOW MOVING
MID LEVEL TROF OUT WEST HAVE BEGUN TO INTERACT WITH THE SFC TROF
DRIFTING SOUTH INTO OUR FORECAST REGION. CONVECTION HAS BEGUN TO
FIRE IN SRN IL NEAR THE JUNCTION OF I 57 AND I 64...OR JUST WEST
OF MOUNT VERNON. THIS ACTIVITY IS LIKELY TO EXPAND QUICKLY IN
COVERAGE THROUGH THE REST OF THE AFTERNOON ALONG THE FRONTAL
BOUNDARY. LI VALUES NOW RUNNING CLOSE TO -4 AHEAD OF THE
FRONT...SO SOME OF THE STORMS WILL NEED TO BE MONITORED FOR THE
POSSIBILITY OF HAIL AND STRONG/GUSTY WINDS.
THE SFC TROF...OR WEAK COLD FRONT...WILL CONTINUE TO DRIFT SLOWLY
SOUTH TONIGHT...BEFORE STALLING NEAR THE OH RIVER. THUS...EXPECT
NUMEROUS SHOWERS AND THUNDERSTORMS OVER MUCH OF THE REGION AS THE
MID LVL TROF TRUDGES VERY SLOWLY EAST INTO THE SOUTHERN
PLAINS....ADDING MOISTURE AND LIFT THE ATMOSPHERE.
A SHORT WAVE ROTATING AROUND THIS MID LVL CIRCULATION WILL
EVENTUALLY LIFT NE THROUGH THE FORECAST AREA LATER TONIGHT...AND
WILL LIKELY BRING A BRIEF BREAK IN RAIN CHANCES OVER SE MO FAR
SOUTHERN IL AND MUCH OF WRN KY LATER TONIGHT.
THEN...WE WILL NEED TO DEAL WITH THE UPPER LOW ITSELF MOVING
EASTWARD THROUGH TN ON THU. WILL LIKELY BRING A BAND OF RAIN WITH
ISOLATED RUMBLES OF THUNDER JUST NORTH OF THE LOW THU.
THUS...HIGHEST RAIN CHANCES THU WILL BE OVER SE MO...THE FAR WRN
KY AND THE SOUTHERN PENNYRILE OF WRN KY. NE WINDS/CLOUDS AND
AREAS OF PRECIP WILL HOLD TEMPS WELL DOWN IN THE 60S IN MOST
LOCATIONS. THIS IS ACTUALLY CLOSE TO NORMAL FOR THIS TIME OF YEAR.
PRECIP SHOULD END QUICKLY FROM NORTH TO SOUTH THU AFTERNOON...AS
THE H50 LOW SCOOTS OFF TO THE SE. IN FACT...EVEN AREAS DOWN NEAR
THE TN BORDER SHOULD SEE AN END TO THE RAIN BEFORE SUNSET.
.LONG TERM...(FRIDAY THROUGH WEDNESDAY)
ISSUED AT 232 PM CDT WED APR 4 2012
THE LATEST MODEL RUNS ARE IN GOOD AGREEMENT FRIDAY WITH SHARP
UPPER LEVEL RIDGING AND A SURFACE HIGH DOMINATING THE WEATHER
FRIDAY AND SATURDAY. THIS WILL RESULT IN VERY DRY AIR ADVECTING
INTO THE REGION AND OVERNIGHT LOWS POSSIBLY FALLING INTO THE UPPER
30S AT LEAST FOR PARTS OF THE AREA. WILL HAVE TO KEEP A CLOSE EYE
ON THE MODEL TRENDS FOR THESE COOL OVERNIGHT LOWS WITH ALL THE
EARLY PLANTING OF TEMPERATURES SENSITIVE CROPS ALREADY IN
PROGRESS. ALSO RH`S WILL BE APPROACHING CRITICAL FIRE WEATHER
THRESHOLDS FRIDAY. WINDS SHOULD DECREASE AS THE HIGH BUILDS INTO
THE REGION. THE MODELS ARE AND HAVE BEEN IN GOOD AGREEMENT WITH A
SATURDAY NIGHT EARLY SUNDAY MORNING COLD FRONT PASSAGE. HOWEVER AS
MODELS OF BEEN HINTING AT FOR A COUPLE DAYS VIA ONLY POST FRONTAL
PRECIP...IT VERY WELL MAY BE A DRY FRONTAL PASSAGE CONSIDERING
THAT ABUNDANT DRY AIR WILL ALREADY BE IN PLACE. THUS MAY NOT SEE
ANY PRECIP WITH MOISTURE STARVED FRONT. ANOTHER REINFORCING FRONT
WILL MOVE THROUGH THE AREA MONDAY BUT IT TO SHOULD BE MOISTURE
STARVED. THUS FROM FRIDAY ON ANY RAINFALL THAT OCCURS OVER THE
AREA SHOULD BE DISCRETE AND FAIRLY LIGHT IN NATURE.
AS FOR TEMPS SHOULD BE ABOVE NORMAL FOR THE WEEKEND THEN COOLING TO
SLIGHTLY BELOW NORMAL STARTING TUESDAY BEHIND THE SECOND COLD FRONT
PASSAGE.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING)
ISSUED AT 700 PM CDT WED APR 4 2012
AS AN UPPER LOW OVER THE SOUTHERN PLAINS DRAWS CLOSER...SCATTERED
SHOWERS AND THUNDERSTORMS WILL REMAIN IN THE FORECAST TONIGHT.
BETTER COVERAGE OF ACTIVITY WILL BE LOCATED OVER NORTHERN PORTIONS
OF THE REGION...NAMELY KEVV AND KOWB...AND PRIMARILY DURING THE
EVENING HOURS. SHOWERS ARE FORECAST TO REDEVELOP MAINLY OVER
SOUTHERN SECTIONS OF THE AREA THURSDAY. EVEN THOUGH MOST OF THE
ACTIVITY WILL BE SOUTH OF KCGI AND KPAH...WILL NEED TO MONITOR AND
ADJUST FORECAST AS CONDITIONS WARRANT. KEPT A CONSERVATIVE APPROACH
WITH RESPECT TO THE INCLUSION OF SHOWERS AND THUNDERSTORMS GIVEN
UNCERTAINTY OF TIMING.
IN THE MEANTIME...A COLD FRONT WILL SAG SLOWLY SOUTH ACROSS THE
REGION OVER THE NEXT 24 HOURS. WINDS WILL SHIFT TO THE NORTHEAST
BEHIND THE FRONT. THERE WILL LIKELY BE A PERIOD OF MVFR CEILINGS
BEHIND THE FRONT...LATE TONIGHT THROUGH EARLY THURSDAY AFTERNOON
AT KEVV AND KOWB...AND THROUGH MUCH OF THURSDAY AT KCGI AND KPAH.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
UPDATE.......RST
SHORT TERM...GM
LONG TERM....KH
AVIATION.....RJP
AREA FORECAST DISCUSSION
NWS PADUCAH KY
536 PM CDT TUE APR 3 2012
.UPDATE...
ISSUED AT 528 PM CDT TUE APR 3 2012
USED THE HRRR MODEL TRENDS FOR THIS FORECAST. A FEW SHOWERS HAVE
DEVELOPED ALONG THE NORTHWEST EDGE OF OUR CWA AND THAT IS EXPECTED
TO CONTINUE FOR THE NEXT COUPLE OF HOURS. MAJORITY OF MODELS WANT
TO DEVELOP AN MCS OVER CENTRAL MISSOURI...MOVE IT EAST THEN
SOUTHEAST WHICH MEANS IT MIGHT CLIP THE SOUTHWEST INDIANA AREA. SO
WENT WITH HIGH CHANCE AND LIKELY POPS OVER THE NORTHERN SECTIONS
TONIGHT. BLENDED A BIT DURING THE MORNING HOURS SO THAT IT IS A
SMOOTHER TRANSITION ACROSS THE SOUTHERN SECTIONS.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 325 PM CDT TUE APR 3 2012
A WEAK SHORT WAVE ALOFT WILL BEGIN TO INTERACT WITH A SURFACE
FRONT LIFTING NORTH OF THE REGION TONIGHT. ACTUALLY WAITING FOR
CONVECTION TO START FIRING OVER THE THE WESTERN HALF OF THE
REGION ANYTIME LATE THIS AFTERNOON. SURFACE HEATING AHEAD OF THIS
SYSTEM...ESP EAST OF THE MS RIVER WILL HELP GENERATE SURFACE BASED
LI VALUES IN THE -4 TO -8 RANGE. IF DEBRIS CLOUDS DO NOT INHIBIT
THIS INSTABILITY FROM FORMING...SOME OF THE THUNDERSTORMS THAT
DEVELOP COULD BE QUITE STRONG TO SEVERE IN THE LATE AFTERNOON INTO
EARLY EVENING. DUE TO RELATIVELY LIGHT FLOW ALOFT...IF ANY
ISOLATED STRONG CONVECTION DOES MANAGE TO DEVELOP...IT WILL
LIKELY BE PULSE-TYPE CLUSTERS IN NATURE...WITH RAPID GROWTH AND DECAY
OF EMBEDDED CELLS.
ONCE THE SFC FRONT AND H50 TROF MOVE NORTH OF THE FORECAST AREA
LATER TONIGHT...WE WILL BE UNDER THE INFLUENCE OF RICH MOIST SW
FLOW AT ALL LEVELS. THOUGH NO REAL TRIGGER IS INDICATED AT THIS
TIME...THIS TYPE OF PATTERN COULD PRODUCE SCATTERED SHOWERS AND
STORMS AT ABOUT ANY TIME. THEREFORE...WILL LEAVE AT LEAST SCT
MENTIONING IN THE FORECAST ALL OF TONIGHT FOR OFF AND ON
SHOWERS/STORMS. GOOD NEWS IS THAT WE WILL LOSE MUCH OF THE DAYTIME
HEATING/INSTABILITY AND MID LEVEL FORCING...SO SEVERE ASPECT WILL
BE LITTLE TO NULL.
LITTLE CHANGE WITH THE MODELS/ENSEMBLES FOR WED. CONTINUE TO SHOW
AN INITIALLY SLOW MOVING CLOSED H5 LOW MOVING ACROSS THE CENTRAL
PLAINS AND INTO W TN BY 06Z FRI AS SURFACE LOW ALSO MOVES SE
ACROSS MAINLY THE SW PART OF THE PAH FORECAST AREA. ACCORDINGLY
THE BEST CHANCE OF SHOWERS/TSTMS WILL GENERALLY BE WEDNESDAY
AFTERNOON INTO WED NIGHT EXCEPT IN THE OZARK FOOTHILLS OF SE MO
WHERE THE BEST CHANCES MAY ARRIVE AS EARLY AS WEDNESDAY MORNING.
A SURFACE HIGH PUSHING S INTO THE GREAT LAKES REGION WILL BRING
DRIER AIR THURSDAY NIGHT.
.LONG TERM...(FRIDAY THROUGH TUESDAY)
ISSUED AT 325 PM CDT TUE APR 3 2012
THE LATEST MODELS AGREE THAT FRIDAY WILL BE A VERY DRY DAY WITH SOME
WIND APPROACHING CRITICAL FIRE WEATHER THRESHOLDS. ALSO WITH WINDS
MAINLY OUT OF THE NORTHEAST WOULD NOT EXPECT MUCH OF A REBOUND ON RH
DURING THE DAY LIKE THE MODELS ARE SUGGESTING. SO WOULD EXPECT AT
LEAST AN INCREASED FIRE DANGER ALTHOUGH FUELS MAY BE WET FROM
PRECEDING RAINS. WILL PULL DEW POINTS DOWN FOR FRIDAY AT LEAST IN
THE MIDDLE 30S FOR NOW AND MONITOR CLOSELY FOR EVEN DRIER WEATHER.
FORECAST SOUNDING WOULD SUGGEST NEAR 30 AND THE NAM WOULD SUGGEST
MID 20S DEW POINTS. WINDS SHOULD DECREASE SATURDAY AS SURFACE HIGH
SETTLES OVER THE HEARTLAND.
BOTH THE 12Z TUE GFS AND 00Z TUE ECMWF ARE IN UNUSUALLY FAIR
AGREEMENT WITH A COLD FRONT TRAVERSING THE REGION SATURDAY NIGHT
INTO SUNDAY MORNING. HOWEVER THE ECMWF IS MUCH DRIER WITH ONLY
SPOTTY QPF...WHILE THE WETTER GFS HAS MORE SOLID COVERAGE AMOUNTS
ARE MEAGER WITH LESS THAN A QUARTER INCH ANYWHERE. HOWEVER THEY BOTH
AGREE THE PRECIP WILL BE POST FRONTAL SHOULD ANY OCCUR. SO WILL
LEAVE IN SLGT CHC IN SUNDAY MORNING AND MIGHT HAVE TO TRIM POPS A
BIT PRIOR TO SUNDAY MORNING TO BETTER REFLECT POST FRONTAL PRECIP.
THERE WILL BE A REINFORCING FRONT MONDAY BRINGING YET ANOTHER SHOT
AT SOME PRECIP. AFTER THAT HIGH PRESSURE RETURNS NEXT WEEK.
AS FOR TEMPS WILL GO WITH ABOVE NORMAL TEMPS OR PERSISTENCE FCST
UNTIL THE REINFORCING FRONT AND THEN WILL ACTUALLY HAVE A SHOT AT
BELOW NORMAL TEMPS BY TUESDAY.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 325 PM CDT TUE APR 3 2012
AN UPPER LEVEL WAVE WILL LIFT NORTH/NORTHEAST ACROSS THE REGION
THIS AFTERNOON. A BAND OF SCATTERED SHOWERS AND A FEW
THUNDERSTORMS SHOULD ACCOMPANY THE UPPER LEVEL FEATURE AS THE
SURFACE HEATS UP AND DESTABILIZES LATE TODAY. BEST CHANCE FOR SCT
TSRA IS AT THE KPAH AND KCGI AIRPORTS THIS AFTERNOON...THEN
SPREADING EAST NORTHEAST INTO THE NIGHT. OTHERWISE...VARIABLE
CLOUDINESS...VFR CONDITIONS...AND SOUTH/SOUTHWEST WINDS MOSTLY
BELOW 10 KTS.
&&
.PAH WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
MO...NONE.
IN...NONE.
KY...NONE.
&&
$$
UPDATE...PS
SHORT TERM...MEFFERT
LONG TERM....KH
AVIATION...MEFFERT
AREA FORECAST DISCUSSION
NWS NEW ORLEANS LA
1144 PM CDT MON APR 2 2012
.AVIATION...
...06Z AVIATION DISCUSSION...
CONVECTION DEVELOPING ALONG A STALLED OUTFLOW BOUNDARY EXTENDING
ALONG THE LOUISIANA COAST WILL BE THE MAIN FEATURE IMPACTING AREA
TERMINALS THROUGH AT LEAST 10Z. EXPECT CONVECTION TO IMPACT
KHUM...KMSY...KNEW...KASD...KHSA...AND KGPT THROUGH 09-10Z THIS
MORNING. THIS CONVECTION WILL PRODUCE PERIODS OF IFR
CONDITIONS...STRONG WIND GUSTS...AND LIGHTNING AS IT MOVES
THROUGH. AFTER 10Z...AN UPPER LEVEL FEATURE DRIVING THE CONVECTIVE
DEVELOPMENT WILL PASS BY THE REGION. THIS WILL ALLOW SOME DRIER
AIR TO FILTER INTO THE AREA...CUTTING OFF CONVECTIVE POTENTIAL.
EXPECT TO SEE SOME PATCHY FOG AND LOW CEILINGS DEVELOP AROUND
12Z...WITH AREAS SEEING IFR AND LIFR CEILINGS TAKE HOLD...AS WELL
AS SOME IFR VISIBILITIES. WINDS WILL INCREASE BY 15Z...AND WILL BE
ABOVE 12 KNOTS FROM 15Z TO AROUND 03Z TOMORROW NIGHT. CLOUDS WILL
BREAK OUT...AS DRIER AIR MIXES DOWN TO THE SURFACE ALLOWING FOR
VFR CONDITIONS AT ALL TERMINALS BY 18Z. 32
&&
.PREV DISCUSSION... /ISSUED 935 PM CDT MON APR 2 2012/
UPDATE...CONVECTION IS BEING RATHER STUBBORN. OLD OUTFLOW BNDRY
CONTINUES TO WORK EAST ACROSS COASTAL MS BUT HAS BASICALLY STALLED
OVER COASTAL LA. IN FACT WHERE THE BNDRY IS ANCHORED(OVER
TERREBONNE...ST MARY...ASSUMPTION...AND ST MARTING PARISHES) IT IS
INTERACTING WITH A COOL POCKET NOTED BY THE RUC. THE RUC IS THE
ONLY MODEL EVEN NOTICING IT RIGHT NOW AS ALL OF THE OTHER HIRES SHORT
RANGE MDLS(12-36 HRS) ARENT EVEN HANDLING THE CURRENT CONVECTION.
THE RUC IS SHOWING THIS COOL POCKET MOVING TO THE NORTH AND
BECOMING ELONGATED FROM NNW-SSE OVER THE WRN QUARTER OF OUR CWA.
WITH THAT I HAVE INCREASED POPS GREATLY FOR OUR SW AND WEST FOR
OVERNIGHT. THERE IS THE POSSIBILITY THAT THERE COULD BE SOME
RATHER HEAVY RAINFALL SOMEWHERE OVER ASSUMPTION...NRN
TERREBONNE...NWRN LAFOURCHE...ST JAMES...AND MAYBE INTO IBERVILLE
AND ASCENSION PARISHES OVERNIGHT. CONVECTION SOUTH OF THE NO METRO
SHOULD CONTINUE TO SLOWLY DRIFT SOUTH AND WEAKEN OVERNIGHT. GRIDS
AND ZONES ARE OUT. /CAB/
&&
.PRELIMINARY POINT TEMPS/POPS...
MCB 66 85 67 83 / 20 40 40 50
BTR 68 85 71 83 / 40 40 40 50
ASD 67 85 69 82 / 20 30 40 50
MSY 71 85 72 82 / 30 30 40 50
GPT 70 81 72 80 / 20 30 40 40
PQL 67 82 71 80 / 20 30 20 40
&&
.LIX WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS CARIBOU ME
907 PM EDT WED APR 4 2012
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL CROSS THE REGION OVERNIGHT. ANOTHER
UPPER DISTURBANCE WILL CROSS THE REGION THURSDAY. HIGH PRESSURE
GRADUALLY BUILDS EAST THURSDAY NIGHT THROUGH SATURDAY.
&&
.NEAR TERM /THROUGH THURSDAY/...
UPDATE 2: LOOKING AT LATEST 06Z NAM...GFS AND HRRR OUTPUT...WE
FEEL FAIRLY CONFIDENT THAT WHATS LEFT OF WEAK SN SHWR BANDING OVR
MSLY NRN PTNS OF THE FA SHOULD END AS SCT FLURRIES LATE TNGT...
SO THE FCST WAS UPDATED TO REFLECT THIS. OTHERWISE...WE AGAIN
INCORPORATED LATEST OBSVD TEMPS INTO THE 00Z TM FRAME AND MERGED
THEM TO OVRNGT LOWS POSTED AT 11Z.
UPDATE 1: FOR NOW...JUST BROUGHT IN LATEST OBSVD HRLY TEMPS AT 22Z
AND MERGED TO OVRNGT LOWS. ALSO...WE KEPT WINDS UP AN ADDITIONAL 5
MPH FROM PREVIOUS FCST UPDATE INTO THE ERLY EVE HRS BASED ON SOME
REPORTING STATIONS STILL EXPERIENCING WIND GUSTS UP TO 20 MPH. WILL
WAIT FOR THE NEXT UPDATE TO SEE HOW SN SHWRS BEGIN TAPERING OFF
ACROSS THE FA LATER THIS EVE BEFORE LOWERING POPS ACROSS THE FA
FASTER THAN LAST UPDATE.
ORGNL DISC: UPPER LEVEL LOW PRESSURE WILL REMAIN ACROSS THE
MARITIMES TONIGHT THROUGH THURSDAY WHILE SEVERAL DISTURBANCES
ROTATE AROUND THE UPPER LOW. ONE DISTURBANCE ROTATING AROUND THE
UPPER LOW WILL CROSS THE REGION EARLY TONIGHT...WITH ANOTHER UPPER
DISTURBANCE STARTING TO MOVE SOUTH ACROSS THE REGION LATER
THURSDAY. RAIN/SNOW SHOWERS WILL DIMINISH THIS EVENING WITH THE
LOSS OF DIURNAL HEATING...THOUGH ISOLATED SNOW SHOWERS COULD
LINGER ACROSS THE NORTH AND MOUNTAINS OVERNIGHT.
OTHERWISE...MOSTLY CLOUDY SKIES ARE EXPECTED ACROSS THE
NORTH/MOUNTAINS TONIGHT...WITH GENERALLY PARTLY CLOUDY SKIES
DOWNEAST. DIURNAL HEATING AND RELATIVELY STEEP MID LEVEL LAPSE
RATES WITH THE UPPER DISTURBANCE WILL SUPPORT MOSTLY CLOUDY SKIES
ALONG WITH ISOLATED RAIN/SNOW SHOWERS ACROSS THE NORTH AND
MOUNTAINS THURSDAY...WITH PARTLY SUNNY SKIES DOWNEAST. WIND GUSTS
OF 25 TO 30 MPH ARE POSSIBLE ACROSS THE REGION THURSDAY. LOW
TEMPERATURES TONIGHT ARE EXPECTED TO RANGE FROM THE UPPER 20S TO
AROUND 30 NORTH...TO AROUND 30 TO THE LOWER 30S DOWNEAST. HIGH
TEMPERATURES THURSDAY ARE EXPECTED TO RANGE FROM AROUND 40 TO THE
LOWER 40S NORTH...TO AROUND 50 DOWNEAST.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
EXPECT A COOL NW FLOW FOR THURSDAY NIGHT WITH LOWS MOSTLY IN THE
MID TO UPPER 20S. A COLD UPPER TROF IS EXPECTED TO CROSS THE AREA
OVERNIGHT AND COULD PRODUCE SOME SNOW SHOWERS IN AROOSTOOK COUNTY
WITH A DUSTING POSSIBLE. THESE SNOW SHOWERS WOULD HAVE LITTLE
VERTICAL EXTENT...REACHING PERHAPS H800. THE BIG QUESTION WILL BE
WHETHER THERE IS ENOUGH H850 MOISTURE TO ACTUALLY PRODUCE THE SNOW
SHOWERS.
FOR FRIDAY...HIGH PRESSURE SLOWLY BUILDS FROM THE OHIO VALLEY AND
THE COOL NW FLOW CONTINUES. SOME WELL-MIXED FAIR WEATHER CU ARE
LIKELY. SUFFICIENT SUNSHINE IS EXPECTED TO BRING HIGHS INTO THE
LOW 40S TOWARDS THE CROWN OF MAINE AND UPPER 40S TO NEAR 50F DOWN
EAST.
THE ONLY CONCERN FOR FRIDAY AND FRIDAY NIGHT WILL BE THE
PERSISTENT UPPER TROF OVER THE AREA. AT THIS TIME...THERE DOES NOT
APPEAR TO BE ENOUGH MOISTURE TO SET OFF ANY RAIN AND SNOW SHOWERS.
AS A RESULT...WILL GO WITH SLIGHT CHC POPS IN SJV...BUT NO POPS
ELSEWHERE. LOWS ON FRIDAY NIGHT SHOULD AGAIN DIP INTO THE MID TO
UPPER 20S.
THE HIGH CONTINUES TO SLOWLY BUILD FOR SATURDAY WITH HIGHS NOW
REACHING THE MID TO UPPER 40S NORTH AND LOW 50S DOWN EAST. THE LOW
LEVEL MOISTURE IS EXPECTED TO SPREAD OUT MORE AND CREATE
STRATOCUMULUS AS SUBSIDENCE ALOFT OCCURS.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
THOUGH THERE ARE A FEW TIMING ISSUES THROUGH THE EXTENDED PERIOD
THE GFS AND ECMWF AGREE THAT THERE WILL BE A STATIONARY UPPER
LEVEL LOW OVER NORTHERN NEW ENGLAND AND SOUTHEASTERN CANADA
THROUGH MOST OF THE PERIOD. A LOW PRESSURE SYSTEM OVER THE NORTH
ATLANTIC WILL BACK INTO MAINE BY EARLY MONDAY MORNING
ECMWF...MONDAY EVENING GFS. BOTH MODELS INDICATE THAT THIS SYSTEM
WILL REMAIN OVER THE AREA THROUGH THE END OF THE EXTENDED PERIOD.
BOTH MODELS ARE INDICATING THAT A SECONDARY LOW WILL DEVELOP AND
TRANSIT THROUGH THE AREA THROUGH THE PERIOD...HOWEVER THE TIMING
OF THE SECONDARY LOW VARIES. THE GFS KEEPS ACTIVE WX THROUGH OUT
THE PERIOD...THE ECMWF SHOW THAT THERE COULD BE A FEW BREAKS IN
WX CONDITIONS. BY THE END OF THE PERIOD BOTH MODELS ARE MOVING THE
UPPER LEVEL LOW EAST INTO THE CANADIAN MARITIMES.
LOADED GMOS FOR BASIC GRIDS. ADJUSTED MAX TEMPS DOWN A BIT DUE TO
CLOUDY...RAIN CONDITIONS. LOADED NAWAVE 4 FOR SEAS IN COASTAL
WATERS.
&&
.AVIATION /22Z WEDNESDAY THROUGH MONDAY/...
NEAR TERM: OCCASIONAL MVFR CONDITIONS ARE EXPECTED ACROSS THE
NORTH AND MOUNTAINS TONIGHT THROUGH THURSDAY...WITH GENERALLY VFR
CONDITIONS DOWNEAST. WIND GUSTS OF 25 TO 30 MPH ARE POSSIBLE
ACROSS THE ENTIRE REGION THURSDAY.
SHORT TERM: VFR CONDITIONS ARE EXPECTED ACROSS THE REGION THURSDAY
NIGHT THROUGH EARLY SUNDAY. MVFR CONDITIONS ARE POSSIBLE LATER
SUNDAY THROUGH MONDAY.
&&
.MARINE...
NEAR TERM: WINDS/SEAS ARE EXPECTED TO REMAIN BELOW SMALL CRAFT
ADVISORY LEVELS TONIGHT THROUGH THURSDAY.
SHORT TERM: NO ISSUES EXPECTED WITH NW WIND GUSTS EXPECTED TO STAY
UNDER 20 KTS AND WAVE HTS GENERALLY 2 FT OR LESS.
&&
.CAR WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...VJN
SHORT TERM...MCW
LONG TERM...NORTON
AVIATION...VJN
MARINE...VJN/MCW
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
338 PM EDT TUE APR 3 2012
.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL MOVE ACROSS THE AREA TONIGHT, BRINGING
THE CHANCE OF SHOWERS AND THUNDERSTORMS. A LINGERING FRONTAL
BOUNDARY BEHIND THE LOW WILL SLIDE SOUTH OF THE AREA AND END THE
CHANCE OF SHOWERS BY WEDNESDAY AFTERNOON. HIGH PRESSURE WILL THEN
BRING DRY AND SEASONABLE CONDITIONS INTO THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
THE LATEST RUC MID-LEVEL ANALYSIS INDICATES A NEAR ZONAL FLOW ON THE
NORTHERN PERIPHERY OF A WEAK RIDGE ACROSS THE OHIO VALLEY. AT THE
SURFACE, A 1009MB LOW IS LOCATED ILLINOIS WITH A WARM FRONT
EXTENDING EASTWARD ACROSS CENTRAL OHIO. A CONVECTIVE COMPLEX
CONTINUES TO WEAKEN AS IT SLIDES SOUTHEAST ACROSS EASTERN OHIO.
THIS EVENING...DRY AIR AT THE SURFACE, INDICATED BY TD DEPRESSIONS
OF 25-30F SHOULD CONTINUE TO LIMIT THE EASTWARD PROGRESSION OF
SHOWERS INTO THE AREA. THE WARM FRONT WILL CONTINUE TO PUSH INTO THE
AREA FROM THE SOUTHWEST AS THE SURFACE LOW TREKS ACROSS THE OHIO
VALLEY. THIS WILL ALLOW FOR TEMPS TO CONTINUE TO WARM INTO THE
EVENING.
TONIGHT...THE SURFACE LOW WILL MOVE INTO WESTERN PENNSYLVANIA AS
THE WARM FRONT STRADDLES THE AREA. NAM/GFS INDICATE AN AREA OF WEAK
ELEVATED INSTABILITY PUSHING ACROSS THE AREA AND ALLOWING FOR THE
CHANCE OF THUNDERSTORMS PRIMARILY SOUTH OF THE PITTSBURGH METRO
OVERNIGHT. BY DAWN, THE FRONTAL BOUNDARY WILL HAVE PUSHED
SOUTHWARD TO THE MASON-DIXON LINE, WITH LINGERING SHOWERS ALONG
AND SOUTH OF THE BOUNDARY. OVERNIGHT LOWS ARE A FEW DEGREES WARMER
THAN LAMP GUIDANCE, RANGING FROM THE LOWER 40S NORTH OF THE
BOUNDARY ALONG THE I-80 CORRIDOR TO THE MID 50S IN NORTH-CENTRAL
WV.
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/...
GFS/ECMWF EQUIV POT TEMP AND DEW POINT GRADIENTS INDICATE THE
FRONTAL BOUNDARY SLIDING FROM THE MASON-DIXON LINE INTO CENTRAL WV
BY 21Z FRIDAY. BEFORE THE BOUNDARY SHIFTS SOUTHWARD, NAM/GFS
INDICATE ENOUGH INSTABILITY TO SUPPORT CHANCE OF THUNDER WEDNESDAY
LATE MORNING INTO THE EARLY AFTERNOON ACROSS PORTIONS OF NORTH-
CENTRAL WV. HIGH PRESSURE APPROACHING FROM THE NORTHWEST ALONG
WITH DRIER AND STABLE AIR WILL ALLOW FOR A DRY FORECAST FOR THE
REMAINDER OF THE DAY ACROSS THE AREA. HIGH TEMPS FOR WEDNESDAY ARE
A FEW DEGREES ABOVE SEASONAL NORMALS.
THERE IS OPERATIONAL MODEL AGREEMENT THAT A SURFACE HIGH WILL MOVE
FROM CENTRAL CANADA INTO THE GREAT LAKES WEDNESDAY NIGHT INTO
FRIDAY. THIS WILL ALLOW FOR CLEARING SKIES WEDNESDAY NIGHT AND
ABUNDANT SUNSHINE THURSDAY AND FRIDAY. TEMPERATURES ARE FORECAST TO
NEAR NORMAL SEASONAL VALUES EACH DAY. WITH THE HIGH FUNNELING IN
COLDER, CANADIAN AIR, FREEZES WILL AGAIN BE POSSIBLE NORTHEAST OF
PITTSBURGH ON THURSDAY AND FRIDAY MORNING.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
BLEND OF RECENT ECMWF AND NAEFS MODEL OUTPUT SHOWS HIGH PRESSURE
OVER THE EASTERN U.S. PROVIDING DRY CONDITIONS ACROSS THE UPPER OHIO
VALLEY INTO AT LEAST SUNDAY AND PERHAPS MONDAY. THEN UPPER LEVEL
RIDGE BUILDING ACROSS THE HIGH PLAINS OF CENTRAL CANADA AND THE U.S.
THIS WILL CAUSE INCREASED NORTHWEST FLOW DOWNWIND INTO THE UPPER
OHIO VALLEY, WITH A SHOWERY COLD FRONTAL PASSAGE EITHER MONDAY OR
TUESDAY.
REGARDING TEMPERATURES, EXPECT A LARGER THAN NORMAL DIURNAL RANGE
SATURDAY DUE TO RELATIVELY CLEAR SKIES ENHANCING RADIATIVE EFFECTS.
LOWS FRIDAY NIGHT CAN BE ABOUT 5 DEGREES COLDER THAN NORMAL, WHILE
SATURDAY AFTERNOON HIGHS CAN BE UP TO 10 DEGREES WARMER THAN NORMAL.
DUE TO COLD FRONTAL PASSAGE TIMING UNCERTAINTY, FORECASTED
TEMPERATURES SUNDAY INTO MONDAY TO BE NEAR SEASONABLE. BY TUESDAY,
THE POSTFRONTAL COOL DOWN WILL CAUSE TEMPERATURES TO BE AT LEAST 5
DEGREES COLDER THAN NORMAL.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
RECENT RADAR AND SURFACE DATA SHOW THE WARM FRONTAL COMPLEX OF
SHOWERS AND SCATTERED THUNDERSTORMS CONTINUING TO MOVE SOUTHEAST
ACROSS CENTRAL OHIO. HAVE MENTIONED SHOWERS FOR KZZV, KHLG AND KMGW,
THROUGH 23Z. ITS POSSIBLE TAF SITES FARTHER NORTH MAY ALSO GET VERY
LIGHT SHOWERS. DESPITE THIS DEVELOPMENT, SURFACE LAYER REMAINS
FAIRLY DRY, SO HAVE MAINTAINED VFR FLIGHT CONDITIONS FOR THE ENTIRE
UPPER OHIO VALLEY THROUGH EARLY TONIGHT.
SEVERAL SREF MODEL OUTPUT MEMBERS SHOW A SECOND COMPLEX OF SHOWERS
AND SCATTERED THUNDERSTORMS, WITH MVFR FLIGHT CONDITIONS, MOVING
SOUTHEASTWARD ACROSS THE I-70 CORRIDOR AND AREAS SOUTH LATE TONIGHT
INTO WEDNESDAY MORNING, 07Z-15Z, IN ASSOCIATION WITH THE PASSAGE OF
A LOW PRESSURE CENTER AND COLD FRONT.
POST FRONTAL DRYING WILL RESTORE VFR THURSDAY AFTERNOON.
SURFACE WINDS WILL VARY THIS AFTERNOON, BUT BECOME NORTHWEST LATE
TONIGHT AND MONDAY AT 5 TO 10 KTS.
OUTLOOK...THURSDAY NIGHT THROUGH SUNDAY...
EXPECT VFR DUE TO HIGH PRESSURE.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
226 PM EDT TUE APR 3 2012
.SYNOPSIS...
A WARM FRONT WILL BRING THE CHANCE OF SHOWERS AND THUNDERSTORMS IN
EASTERN OHIO THIS AFTERNOON. LOW PRESSURE MOVING ACROSS THE OHIO
VALLEY TODAY WILL MOVE INTO THE AREA OVERNIGHT AND BRING
SCATTERED SHOWERS AND THUNDERSTORMS. CANADIAN HIGH PRESSURE WILL
FOLLOW WITH DRY, SEASONABLE CONDITIONS INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE 18Z ENHANCED SHORT TERM FORECAST UPDATE HAS BEEN ISSUED TO
ACCOUNT FOR THE LATEST RADAR TRENDS, INCREASING POPS IN EASTERN
OHIO AND MOVING POPS INTO PORTIONS OF WV AND PA. IN ADDITION,
TEMPS HAVE BEEN DECREASED IN RAIN-COOLED PORTIONS OF EASTERN OHIO.
THE LATEST RUC MID-LEVEL ANALYSIS INDICATES A NEAR ZONAL FLOW ON
THE NORTHERN PERIPHERY OF A WEAK RIDGE ACROSS THE OHIO VALLEY. AT
THE SURFACE, A 1009MB LOW IS LOCATED ILLINOIS WITH A WARM FRONT
EXTENDING EASTWARD ACROSS CENTRAL OHIO. A CONVECTIVE COMPLEX
CONTINUES TO WEAKEN AS IT SLIDES SOUTHEAST INTO EASTERN OHIO.
THIS AFTERNOON...CONVECTION ACROSS EASTERN AND CENTRAL OHIO WILL
WEAKEN AND DIMINISH AS IT ENCOUNTERS DRIER AIR AND SLIDES
SOUTHEASTWARD INTO WESTERN PA AND NORTHERN WV. A FEW RUMBLES OF
THUNDER ARE NOT OUT OF THE QUESTION WEST OF I-77 IN OHIO. OTHERWISE,
DRY AIR AT THE SURFACE, INDICATED BY TD DEPRESSIONS OF 25-30F,
SHOULD LIMIT THE EASTWARD PROGRESSION OF SHOWERS INTO THE AREA.
THE WARM FRONT WILL PUSH INTO THE AREA FROM THE SOUTHWEST AS THE
SURFACE LOW TREKS ACROSS THE OHIO VALLEY AND TEMPS WILL CONTINUE
TO WARM INTO THE EVENING. FORECAST CONSISTS OF A HRRR/LAMP BLEND,
WITH HIGHS RANGING FROM THE MID 70S ACROSS EASTERN OHIO AND NORTH-
CENTRAL WV TO THE MID 60S ALONG THE I-80 CORRIDOR.
TONIGHT...THE SURFACE LOW WILL MOVE INTO WESTERN PENNSYLVANIA AS
THE WARM FRONT STRADDLES THE AREA. MODERATE INSTABILITY UPSTREAM
IN OHIO WILL ALLOW FOR CONVECTION TO DEVELOP THERE AND THEN PUSH
INTO THE AREA OVERNIGHT. NAM/GFS INDICATE AN AREA OF ELEVATED
INSTABILITY PUSHING ACROSS EASTERN OHIO AND ALLOWING FOR THE
CHANCE OF THUNDERSTORMS TO CONTINUE ACROSS THE AREA OVERNIGHT.
VERTICAL SHEAR IS RELATIVELY WEAK, SO BELIEVE THE SEVERE THREAT
WILL BE LIMITED. HOWEVER, CANNOT RULE OUT THE ISOLATED POSSIBILITY
OF HAIL IN EASTERN OHIO. BY DAWN, THE FRONTAL BOUNDARY WILL HAVE
PUSHED SOUTHWARD TO THE MASON-DIXON LINE, WITH LINGERING SHOWERS
ALONG AND SOUTH OF THE BOUNDARY. OVERNIGHT LOWS ARE A FEW DEGREES
WARM THAN LAMP GUIDANCE, RANGING FROM THE LOWER 40S NORTH OF THE
BOUNDARY ALONG THE I-80 CORRIDOR TO THE MID 50S IN NORTH-CENTRAL
WV.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
PASSAGE OF THE LOW PRESSURE LATE TNGT/EARLY WEDNESDAY WL AMPLIFY FLOW
ALOFT/PUSH A COLD FRONT ACROSS THE AREA. SHOWER AND THUNDERSTORM
CHANCES ARE THUS FORECAST TO INCREASE TONIGHT AS LOW PRESSURE CENTER IS
PROJECTED TO MOVE EASTWARD ALONG THE SOUTHWARD SAGGING FRONTAL
BOUNDARY. PRECIP PROBABILITIES IN THE CHANCE CATEGORY WL BE
MAINTAINED FOR MOST ZONES GIVEN PROGS OF LIMITED MOISTURE
RETURN...BUT LIKELY NUMBERS WL BE INCLUDED FOR COUNTIES ALONG AND
SOUTH OF I 70 AS THE ADVANCING LOW IMPROVES THE MOISTURE PROFILE
FOR THOSE ZONES.
THE STORM PREDICTION CENTER HAS A SLIGHT RISK OF SEVERE
THUNDERSTORMS FOR PARTS OF EAST CENTRAL OHIO FOR TONIGHT. HAVE
OPTED TO MENTION NO MORE THAN A LOW PROBABILITY AT THIS TIME AS
MOST SREF MODEL MEMBERS SHOW RATHER WEAK INSTABILITY AND VERTICAL
SHEAR.
AT ANY RATE...THAT LOW WL ALSO PULL THE COLD FRONT SUFFICIENTLY
SOUTHWARD WITH ITS WEDNESDAY PASSAGE TO QUICKLY DRY THE WEATHER
FOR THE REMAINDER OF THE SHORT TERM PERIOD.
TROUGH ALOFT/COOL HIGH PRESSURE ON THE SURFACE WL RETURN TEMPERATURES
BACK TO NORMAL...WITH FREEZES POSSIBLE ON THURSDAY AND FRIDAY
MORNINGS ACROSS THE AREAS NORTH AND EAST OF PITTSBURGH.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
BLEND OF RECENT ECMWF AND NAEFS MODEL OUTPUT SHOWS HIGH PRESSURE
OVER THE EASTERN U.S. PROVIDING DRY CONDITIONS ACROSS THE UPPER OHIO
VALLEY INTO DAYTIME SUNDAY. CONSENSUS OF MODELS THEN SHOW THE UPPER
LEVEL JET STREAM PATTERN BECOMING MORE ZONAL WITH A SOUTHWEST
ORIENTATION. THIS ZONAL UPPER FLOW WILL STEER A COLD FRONTAL BAND OF
SHOWERS EASTWARD THROUGH THE UPPER OHIO VALLEY SUNDAY NIGHT INTO
MONDAY.
FORECASTED TEMPERATURES, USING BLEND OF GFS AND NAEFS MODEL OUTPUT,
TO BE NEAR NORMAL FRIDAY, FOLLOWED BY A PREFRONTAL WARM UP SATURDAY
AND SUNDAY TO VALUES UP TO 10 DEGREES ABOVE NORMAL. TEMPERATURES
MONDAY SHOULD BE CLOSER TO NORMAL DUE TO CLOUDS AND SHOWERS AND
POTENTIAL POSTFRONTAL COOLING, ALTHOUGH THE LATTER WILL BE LIMITED
BY THE SOUTHWEST WINDS ALOFT.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
RECENT RADAR AND SURFACE DATA SHOW THE WARM FRONTAL COMPLEX OF
SHOWERS AND SCATTERED THUNDERSTORMS CONTINUING TO MOVE SOUTHEAST
ACROSS CENTRAL OHIO. HAVE MENTIONED SHOWERS FOR KZZV, KHLG AND KMGW,
THROUGH 23Z. ITS POSSIBLE TAF SITES FARTHER NORTH MAY ALSO GET VERY
LIGHT SHOWERS. DESPITE THIS DEVELOPMENT, SURFACE LAYER REMAINS
FAIRLY DRY, SO HAVE MAINTAINED VFR FLIGHT CONDITIONS FOR THE ENTIRE
UPPER OHIO VALLEY THROUGH EARLY TONIGHT.
SEVERAL SREF MODEL OUTPUT MEMBERS SHOW A SECOND COMPLEX OF SHOWERS
AND SCATTERED THUNDERSTORMS, WITH MVFR FLIGHT CONDITIONS, MOVING
SOUTHEASTWARD ACROSS THE I-70 CORRIDOR AND AREAS SOUTH LATE TONIGHT
INTO WEDNESDAY MORNING, 07Z-15Z, IN ASSOCIATION WITH THE PASSAGE OF
A LOW PRESSURE CENTER AND COLD FRONT.
POST FRONTAL DRYING WILL RESTORE VFR THURSDAY AFTERNOON.
SURFACE WINDS WILL VARY THIS AFTERNOON, BUT BECOME NORTHWEST LATE
TONIGHT AND MONDAY AT 5 TO 10 KTS.
OUTLOOK...THURSDAY NIGHT THROUGH SUNDAY...
EXPECT VFR DUE TO HIGH PRESSURE.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1200 PM EDT TUE APR 3 2012
.SYNOPSIS...
A WARM FRONT WILL BRING THE CHANCE OF SHOWERS AND THUNDERSTORMS IN
EASTERN OHIO THIS AFTERNOON. LOW PRESSURE MOVING ACROSS THE OHIO
VALLEY TODAY WILL MOVE INTO THE AREA OVERNIGHT AND BRING
SCATTERED SHOWERS AND THUNDERSTORMS. CANADIAN HIGH PRESSURE WILL
FOLLOW WITH DRY, SEASONABLE CONDITIONS INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AN ENHANCED SHORT TERM FORECAST UPDATE HAS BEEN ISSUED TO ADD POPS
IN EASTERN OHIO AS WEAKENING CONVECTION MOVES INTO THE AREA.
THE LATEST RUC MID-LEVEL ANALYSIS INDICATES A NEAR ZONAL FLOW ON
THE NORTHERN PERIPHERY OF A WEAK RIDGE ACROSS THE OHIO VALLEY. AT
THE SURFACE, A 1010MB IS LOCATED ACROSS CENTRAL ILLINOIS WITH A
WARM FRONT EXTENDING INTO NORTHERN OHIO. A CONVECTIVE COMPLEX IN
NORTHERN OHIO HAS DEVELOPED WITH OVERRUNNING ALONG AND AHEAD OF THE
WARM FRONT.
TODAY...CONVECTION ACROSS NORTHERN OHIO WILL WEAKEN AND DIMINISH
AS IT ENCOUNTERS DRIER AIR AND SLIDES SOUTHEASTWARD INTO EAST-
CENTRAL OHIO. THUS, CHANCE POPS ARE FORECAST THIS AFTERNOON THERE.
OTHERWISE, DRY AIR AT THE SURFACE, INDICATED BY TD DEPRESSIONS OF
25-30F, SHOULD LIMIT THE INITIAL EASTWARD PROGRESSION OF SHOWERS
INTO THE AREA. THE WARM FRONT WILL PUSH INTO THE AREA FROM THE
SOUTHWEST AS THE SURFACE LOW TREKS ACROSS THE OHIO VALLEY AND
TEMPS WILL CONTINUE TO WARM INTO THE EVENING. FORECAST CONSISTS OF
A HRRR/LAMP BLEND, WITH HIGHS RANGING FROM THE MID 70S ACROSS
EASTERN OHIO AND NORTH-CENTRAL WV TO THE MID 60S ALONG THE I-80
CORRIDOR.
TONIGHT...THE SURFACE LOW WILL MOVE INTO WESTERN PENNSYLVANIA AS
THE WARM FRONT STRADDLES THE AREA. MODERATE INSTABILITY UPSTREAM IN OHIO
WILL ALLOW FOR CONVECTION TO DEVELOP THERE AND THEN PUSH INTO THE
AREA OVERNIGHT. NAM/GFS INDICATE AN AREA OF ELEVATED INSTABILITY
PUSHING ACROSS EASTERN OHIO AND ALLOWING FOR THE CHANCE OF
THUNDERSTORMS TO CONTINUE ACROSS THE AREA OVERNIGHT. VERTICAL
SHEAR IS RELATIVELY WEAK, SO BELIEVE THE SEVERE THREAT WILL BE
LIMITED. HOWEVER, CANNOT RULE OUT THE ISOLATED POSSIBILITY OF
HAIL IN EASTERN OHIO. BY DAWN, THE FRONTAL BOUNDARY WILL HAVE
PUSHED SOUTHWARD TO THE MASON-DIXON LINE, WITH LINGERING SHOWERS
ALONG AND SOUTH OF THE BOUNDARY. OVERNIGHT LOWS ARE A FEW DEGREES
WARM THAN LAMP GUIDANCE, RANGING FROM THE LOWER 40S NORTH OF THE
BOUNDARY ALONG THE I-80 CORRIDOR TO THE MID 50S IN NORTH-CENTRAL WV.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
PASSAGE OF THE LOW PRESSURE LATE TNGT/EARLY WEDNESDAY WL AMPLIFY FLOW
ALOFT/PUSH A COLD FRONT ACROSS THE AREA. SHOWER AND THUNDERSTORM
CHANCES ARE THUS FORECAST TO INCREASE TONIGHT AS LOW PRESSURE CENTER IS
PROJECTED TO MOVE EASTWARD ALONG THE SOUTHWARD SAGGING FRONTAL
BOUNDARY. PRECIP PROBABILITIES IN THE CHANCE CATEGORY WL BE
MAINTAINED FOR MOST ZONES GIVEN PROGS OF LIMITED MOISTURE
RETURN...BUT LIKELY NUMBERS WL BE INCLUDED FOR COUNTIES ALONG AND
SOUTH OF I 70 AS THE ADVANCING LOW IMPROVES THE MOISTURE PROFILE
FOR THOSE ZONES.
THE STORM PREDICTION CENTER HAS A SLIGHT RISK OF SEVERE
THUNDERSTORMS FOR PARTS OF EAST CENTRAL OHIO FOR TONIGHT. HAVE
OPTED TO MENTION NO MORE THAN A LOW PROBABILITY AT THIS TIME AS
MOST SREF MODEL MEMBERS SHOW RATHER WEAK INSTABILITY AND VERTICAL
SHEAR.
AT ANY RATE...THAT LOW WL ALSO PULL THE COLD FRONT SUFFICIENTLY
SOUTHWARD WITH ITS WEDNESDAY PASSAGE TO QUICKLY DRY THE WEATHER
FOR THE REMAINDER OF THE SHORT TERM PERIOD.
TROUGH ALOFT/COOL HIGH PRESSURE ON THE SURFACE WL RETURN TEMPERATURES
BACK TO NORMAL...WITH FREEZES POSSIBLE ON THURSDAY AND FRIDAY
MORNINGS ACROSS THE AREAS NORTH AND EAST OF PITTSBURGH.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
BLEND OF RECENT ECMWF AND NAEFS MODEL OUTPUT SHOWS HIGH PRESSURE
OVER THE EASTERN U.S. PROVIDING DRY CONDITIONS ACROSS THE UPPER OHIO
VALLEY INTO DAYTIME SUNDAY. CONSENSUS OF MODELS THEN SHOW THE UPPER
LEVEL JET STREAM PATTERN BECOMING MORE ZONAL WITH A SOUTHWEST
ORIENTATION. THIS ZONAL UPPER FLOW WILL STEER A COLD FRONTAL BAND OF
SHOWERS EASTWARD THROUGH THE UPPER OHIO VALLEY SUNDAY NIGHT INTO
MONDAY.
FORECASTED TEMPERATURES, USING BLEND OF GFS AND NAEFS MODEL OUTPUT,
TO BE NEAR NORMAL FRIDAY, FOLLOWED BY A PREFRONTAL WARM UP SATURDAY
AND SUNDAY TO VALUES UP TO 10 DEGREES ABOVE NORMAL. TEMPERATURES
MONDAY SHOULD BE CLOSER TO NORMAL DUE TO CLOUDS AND SHOWERS AND
POTENTIAL POSTFRONTAL COOLING, ALTHOUGH THE LATTER WILL BE LIMITED
BY THE SOUTHWEST WINDS ALOFT.
&&
.AVIATION /16Z TUESDAY THROUGH SATURDAY/...
RECENT SURFACE AND SATELLITE DATA SHOW VFR WILL CONTINUE ACROSS THE
UPPER OHIO VALLEY THIS AFTERNOON. RECENT RADAR DATA CONTINUES TO
SHOW A SLOW SOUTHEASTWARD MOVING THUNDERSTORM COMPLEX OVER NORTHERN
OHIO. RECENT HRRR MODEL OUTPUT CONTINUES TO SHOW DISSIPATION BEFORE
AFFECTING ANY TAF SITES SUCH AS KZZV OR KFKL. HENCE HAVE MAINTAINED
VFR INTO EVENING.
SURFACE WINDS WILL BECOME SOUTH TO SOUTHWEST NEAR 10 KTS THIS
AFTERNOON.
OUTLOOK...TONIGHT THROUGH SATURDAY...
RESTRICTIONS POSSIBLE LATER TONIGHT INTO WEDNESDAY MORNING DUE TO
SHOWERS AND POSSIBLE THUNDERSTORMS ASSOCIATED WITH COLD FRONTAL
PASSAGE. VFR WEDNESDAY AFTERNOON INTO SATURDAY DUE TO HIGH PRESSURE.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
839 AM EDT TUE APR 3 2012
.SYNOPSIS...
LOW PRESSURE, COMING EAST FROM IOWA, WILL PUSH A COLD FRONT WITH
SCATTERED SHOWERS AND THUNDERSTORMS THROUGH THE UPPER OHIO VALLEY
TONIGHT. CANADIAN HIGH PRESSURE WILL FOLLOW WITH DRY, SEASONABLE CONDITIONS
INTO THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
HAVE ALLOWED FREEZE WARNING TO EXPIRE AT 8 AM. RECENT SURFACE DATA
SHOWS SURFACE TEMPERATURES IN MANY AREAS WILL HAVE WARMED PAST 32
BEFORE 9 AM. SO ANY REMAINING PATCHES OF FROST WILL GONE BY THEN
ALSO.
RECENT RADAR DATA SHOWS A THUNDERSTORM COMPLEX MOVING
SOUTHEASTWARD OUT OF SOUTHERN MICHIGAN, WHICH WILL NEED MONITORED.
DRY CONDITIONS OVER THE UPPER OHIO VALLEY SHOULD CAUSE THIS
COMPLEX TO WEAKEN OR DISSIPATE BEFOREHAND. MOST MODELS SUPPORT
THIS IDEA OF DISSIPATION INCLUDING RECENT HRRR MODEL OUTPUT.
HOWEVER, WRF-NMM SUGGESTS DAYTIME WARMING AND AN INCREASE IN
SURFACE LAYER MOISTURE, DUE TO POSSIBLE WARM FRONTOGENESIS THIS
AFTERNOON, MAY AID REDEVELOPMENT OVER EAST CENTRAL OHIO BEFORE
EVENING.
TODAYS WARM ADVECTION REGIME SUPPORTS TEMPERATURES ABOUT 10
DEGREES ABOVE THE SEASONAL AVERAGES. READING WERE FORECAST USING
TWEAKED SREF NUMBERS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
PASSAGE OF THE LOW PRESSURE LATE TNGT/EARLY WEDNESDAY WL AMPLIFY FLOW
ALOFT/PUSH A COLD FRONT ACROSS THE AREA. SHOWER AND THUNDERSTORM
CHANCES ARE THUS FORECAST TO INCREASE TONIGHT AS LOW PRESSURE CENTER IS
PROJECTED TO MOVE EASTWARD ALONG THE SOUTHWARD SAGGING FRONTAL
BOUNDARY. PRECIP PROBABILITIES IN THE CHANCE CATEGORY WL BE
MAINTAINED FOR MOST ZONES GIVEN PROGS OF LIMITED MOISTURE
RETURN...BUT LIKELY NUMBERS WL BE INCLUDED FOR COUNTIES ALONG AND
SOUTH OF I 70 AS THE ADVANCING LOW IMPROVES THE MOISTURE PROFILE
FOR THOSE ZONES.
THE STORM PREDICTION CENTER HAS A SLIGHT RISK OF SEVERE
THUNDERSTORMS FOR PARTS OF EAST CENTRAL OHIO FOR TONIGHT. HAVE
OPTED TO MENTION NO MORE THAN A LOW PROBABILITY AT THIS TIME AS
MOST SREF MODEL MEMBERS SHOW RATHER WEAK INSTABILITY AND VERTICAL
SHEAR.
AT ANY RATE...THAT LOW WL ALSO PULL THE COLD FRONT SUFFICIENTLY
SOUTHWARD WITH ITS WEDNESDAY PASSAGE TO QUICKLY DRY THE WEATHER
FOR THE REMAINDER OF THE SHORT TERM PERIOD.
TROUGH ALOFT/COOL HIGH PRESSURE ON THE SURFACE WL RETURN TEMPERATURES
BACK TO NORMAL...WITH FREEZES POSSIBLE ON THURSDAY AND FRIDAY
MORNINGS ACROSS THE AREAS NORTH AND EAST OF PITTSBURGH.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
BLEND OF RECENT ECMWF AND NAEFS MODEL OUTPUT SHOWS HIGH PRESSURE
OVER THE EASTERN U.S. PROVIDING DRY CONDITIONS ACROSS THE UPPER OHIO
VALLEY INTO DAYTIME SUNDAY. CONSENSUS OF MODELS THEN SHOW THE UPPER
LEVEL JET STREAM PATTERN BECOMING MORE ZONAL WITH A SOUTHWEST
ORIENTATION. THIS ZONAL UPPER FLOW WILL STEER A COLD FRONTAL BAND OF
SHOWERS EASTWARD THROUGH THE UPPER OHIO VALLEY SUNDAY NIGHT INTO
MONDAY.
FORECASTED TEMPERATURES, USING BLEND OF GFS AND NAEFS MODEL OUTPUT,
TO BE NEAR NORMAL FRIDAY, FOLLOWED BY A PREFRONTAL WARM UP SATURDAY
AND SUNDAY TO VALUES UP TO 10 DEGREES ABOVE NORMAL. TEMPERATURES
MONDAY SHOULD BE CLOSER TO NORMAL DUE TO CLOUDS AND SHOWERS AND
POTENTIAL POSTFRONTAL COOLING, ALTHOUGH THE LATTER WILL BE LIMITED
BY THE SOUTHWEST WINDS ALOFT.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
SKIES WILL BE CLEAR UNDER HIGH PRESSURE WITH CALM WINDS INTO MID
MORNING THEN A FEW CU WILL DEVELOP BY AFTERNOON. AS SURFACE RIDGE
SHIFTS EAST WINDS WILL BECOMING SOUTH UNDER 10 KTS.
OUTLOOK...TONIGHT THROUGH SATURDAY...
RESTRICTIONS POSSIBLE LATE TONIGHT INTO FIRST HALF OF WEDNESDAY WITH
SHOWERS AND POSSIBLE THUNDERSTORMS ASSOCIATED WITH COLD FRONTAL PASSAGE.
VFR WEDNESDAY AFTERNOON INTO SATURDAY DUE TO HIGH PRESSURE.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
149 PM EDT TUE APR 3 2012
.SYNOPSIS...
ISSUED AT 533 AM EDT TUE APR 3 2012
RIDGE OVER THE AREA SINCE LATE IN THE WEEKEND IS BEING FLATTENED
OUT THIS MORNING AS STRONG SHORTWAVE TROUGH SLIDES FM MANITOBA INTO
NORTHWEST ONTARIO. HEIGHT FALLS ARE SUBTLE OVR UPR LAKES PER 00Z
RAOBS BUT ENOUGH TO TRIGGER MULTIPLE CLUSTERS OF SHRA/TSRA OVR THE
UPPER GREAT LAKES. FRONTAL BOUNDARY...EXTENDING SOUTH OUT OF LOW OVR
NORTHERN ONTARIO AND ALSO EXTENDING TO THE NORTH FM LOW OVR MID
MISSISSIPI RIVER VALLEY WILL CROSS UPR MICHIGAN THIS MORNING. COOLER
AIRMASS ADVECTS OVR THE AREA LATER TODAY THROUGH TONIGHT AND
WEDNESDAY. AFTER THE FROPA THIS MORNING...DRY WEATHER WILL PREVAIL
THROUGH LATE THIS WEEK AS LARGE HIGH PRESSURE IS DOMINANT WEATHER
FEATURE.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 533 AM EDT TUE APR 3 2012
TODAY...CONVECTIVE TRENDS WILL BE CHALLENGING THIS MORNING...BUT
AFTER THAT DRYING TREND WILL FIRMLY TAKE HOLD. AS OCCURRED 24 HR
AGO...MAIN AREA OF CONVECTION OVERNIGHT HAS DEVELOPED CLOSER TO H7
MOIST AXIS AND ALSO IN AREA OF H85 TEMP ADVECTION. INITIAL SHRA/TSRA
HEADING QUICKLY INTO THE FAR EAST CWA FORMED AHEAD OF ONTARIO
SHORTWAVE TROUGH AND HAVE BEHAVED FOLLOWING STEADY EASTWARD MOTION.
CONVECTION OVR MN AND WESTERN WI IS OUTLINED WELL BY WHERE RUC13
SHOWS MAXIMUM H7 MOISTURE TRANSPORT AND ON NORTHERN EDGE OF STEEPER
H7-H5 LAPSE RATES AOA 8C/KM. AT THIS TIME...MAJORITY OF TSRA ARE
OCCURRING OVR CNTRL WI BUT ADDITIONAL SHRA WITH EMBEDDED TSRA ARE
FILLING IN INTO NORTHWEST WI. FOLLOWING RUC IDEA THERE IS ENOUGH H7
MOISTURE TRANSPORT INTO SCNTRL CWA TO KEEP HIGHER POPS THERE IN THE
MORNING. A FEW SHRA/TSRA MAY EVEN CLIP AREAS FARTHER NORTH IN THE
CNTRL CWA BUT IT IS FAIRLY LIMITED CHANCE AS THE AREA OF SHRA/TSRA
OVR NORTHWEST WI WILL BE OUTRUNNING BETTER H7 MOISTURE CONVERGENCE
AND ELEVATED INSTABILITY IF THEY CONTINUE ON ENE TRACK. OVERALL
IMAGINE CHANCES OF CONVECTION WILL BEGIN TO WANE SIGNIFICANTLY OVR
MOST AREAS AFTER MID MORNING /POST 15Z-16Z/ SINCE SFC FRONT WILL BE
DROPPING S/SE OF THE AREA BY THAT TIME. HAVE HAD SOME PEA-SIZED HAIL
OVERNIGHT WITH STRONGER STORMS AND THAT REMAINS POSSIBLE THIS
MORNING GIVEN STEEP LAPSE RATES JUST UPSTREAM AND 30-35 KTS OF
EFFECTIVE SHEAR FCST OVR CNTRL PORTIONS OF UPR MI.
AS ALLUDED TO BEFORE...COLD FRONT WILL STEADILY SLIDE ACROSS THE
AREA MID TO LATE MORNING. WINDS IN WAKE OF FRONT EXPECTED TO BECOME
NORTH TO NORTHWEST. STILL APPEARS THAT THERE COULD BE BRIEF PERIOD
OF LOWER CIGS AND MAYBE SOME FOG AS HIGHER DWPNTS JUST BEHIND FRONT
SETTLE ACROSS LK SUPERIOR AND WINDS PROVIDE SOME UPSLOPE LIFTING OVR
HIGHER TERRAIN OF WESTERN AND NORTH CENTRAL CWA. POSSIBILITY FOR FOG
MAY HAVE BEEN ENHANCED DUE TO THE DECENT COVERAGE OF SHRA/TSRA OVR
LK SUPERIOR OVERNIGHT THAT MAY HAVE PROVIDED ADDITIONAL LOW-LEVEL
MOISTENING. LOOKING UPSTREAM THERE IS AREA OF LOWER CLOUDS NORTHWEST
OF LK SUPERIOR BUT THERE IS ALSO A MUCH LARGER AREA OF VERY DRY
AIR/CLEAR SKIES PUSHING ACROSS MANITOBA AND NORTHWEST ONTARIO.
REALLY HARD TO TELL AT THIS POINT HOW MUCH/IF ANY FOG IS PRESENT OVR
WESTERN LK SUPERIOR...SO WILL NOT INCLUDE IN FCST FOR LATER THIS
MORNING. EXPECT DRYING TO WIN OUT PRETTY EASILY AFTER MID AFTN ONCE
BLYR DWPNTS FALL INTO THE LOWER 30S/MID-UPR 20S AS HIGH BEGINS TO
NOSE INTO LK SUPERIOR REGION. SO SKY FCST SHAKES OUT AS FAIRLY
CLOUDY IN THE MORNING BUT WITH FAIRLY SHARP CLEARING TREND BY MID
AFTN FM WEST-TO-EAST. DESPITE THE SUNSHINE THIS AFTN...TEMPS SHOULD
BE HELD DOWN MOST AREAS WITH GRADIENT WIND FLOWING OFF LK SUPERIOR.
PROBABLY WILL SEE STEADY TEMPS ALONG LK SUPERIOR AND READINGS
PUSHING INTO LOWER 50S FAR INLAND/LK MICHIGAN SHORE WITH LESS LAKE
MODIFICATION GIVEN THE NORTHWEST WINDS. DWPNTS AND RH VALUES COULD
CRASH OVR INTERIOR WEST BY LATE AFTN. CURRENT FCST HAS RH VALUES IN
THE 30-40 PCT RANGE...BUT IF WINDS STAY MORE NW IT COULD GET WARMER
WHICH WOULD RESULT IN RH VALUES BLO 30 PCT.
VERY DRY AIRMASS BECOMES FIRMLY ENTRENCHED OVR AREA TONIGHT INTO
WEDNESDAY AS HIGH PRESSURE BUILDS FM HUDSON BAY INTO THE WESTERN
GREAT LAKES. NORTHERLY FLOW REMAINS OFF LK SUPERIOR BUT GIVEN PWATS
FALLING TOWARD 50 PCT OF NORMAL...EXPECT INTERIOR CWA TO TRY TO
DECOUPLE TONIGHT AND COOL OFF TOWARD THE LOWER DWPNTS ADVECTING INTO
THE REGION. BENEATH MOSTLY SUNNY SKIES ON WEDNESDAY...MAIN CONCERN
WILL BE ON FIRE WX WITH LOWER RH VALUES. HAVE DWPNTS IN AFTN MIXING
OUT INTO THE UPR TEENS OVR INTERIOR SECTIONS...RESULTING IN RH
VALUES BLO 30 PCT. WINDS WILL NOT BE VERY GUSTY /LEADING TO LESS
IMPACT ON FIRE WX CUSTOMERS/ BUT A STEADY NORTH WIND UP TO 15 MPH IS
EXPECTED. GIVEN THE FLOW...PROBABLY WILL HAVE TOUGH TIME REACHING 40
DEGREES ALONG LK SUPERIOR SHORE. MIXING HEIGHTS MUCH HIGHER TOWARD
WI BORDER /H85-H8 PER FCST SOUNDINGS/ ALLOW TEMPS TO RISE WELL INTO
THE 50S. OVERALL LOOKS LIKE PRETTY TYPICAL SPRING PATTERN.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 533 AM EDT TUE APR 3 2012
HIGH PRESSURE WILL DOMINATE MUCH OF THIS PERIOD. WHILE THE SFC RIDGE
WILL BE OVERHEAD AT 00Z THURSDAY...THE MAIN HIGH WILL LIKELY RESIDE
OVER HUDSON BAY AND NW ONTARIO. EXPECT THE CENTER OF HIGH PRESSURE
TO SLOWLY SIDE OVER LAKE SUPERIOR THURSDAY INTO FRIDAY. DRY AIR WILL
CONTINUE TO SLIDE INTO THE AREA FROM EASTERN ONTARIO...WITH HUMIDITY
VALUES FALLING 25 TO 25 PERCENT THURSDAY AND FRIDAY AFTERNOON AWAY
FROM THE LAKE SUPERIOR COASTLINE. ON THE PLUS SIDE...WINDS SHOULD BE
FAIRLY LIGHT...LESS THAN 10KTS AWAY FROM ANY LAKE BREEZES THAT MAY
COME IN THURSDAY AND FRIDAY AFTERNOON. STILL...IT WILL BE ENOUGH TO
INCREASE FIRE WEATHER CONCERNS OVER UPPER MICHIGAN THROUGH THE
REMAINDER OF THE WORK WEEK.
THERE WILL BE A SUBTLE CHANGE FRIDAY...AS THE HIGH PRESSURE SYSTEM
BEGINS TO SHIFT EASTWARD IN RESPONSE TO A SFC LOW ORGANIZING OVER
EASTERN WY/MT INTO THE WESTERN DAKOTAS. LOOK FOR A SLOW RETURN TO
S/SE WINDS FRIDAY INTO FRIDAY NIGHT.
THE PRESSURE GRADIENT WILL TIGHTEN OVER THE WEEKEND. EXPECT
INCREASED S/SE WINDS OF 10 TO 15KTS SATURDAY /AHEAD OF THE COLD
FRONT CROSSING SATURDAY NIGHT/. SPECIFICS FOR THIS PERIOD ARE A
LITTLE TRICKY...WITH THE BREAKDOWN OF THE 500MB RIDGE SATURDAY NIGHT
AS THE MAIN LOW REMAINS WELL TO OUR NORTH. THE 03/00Z RUN OF THE
ECMWF CONTINUES TO SHOW LIMITED MOISTURE...WITH LITTLE MORE THAN A
TRACE OF RAIN FALLING SATURDAY NIGHT AS MUCH OF THE ENERGY REMAINS
WRAPPED UP ACROSS CANADA MAINLY ON THE BACK SIDE OF THE LOW. THE
03/00Z RUN OF THE GFS ON THE OTHER HAND INDICATES THE POTENTIAL FOR
AROUND A TENTH OF AN INCH OF WELL NEEDED RAIN...WITH STILL THE BEST
CHANCE BEHIND THE LOW. GIVEN THE LOW POTENTIAL FOR EVEN RAIN...KEPT
ONLY SLIGHT CHANCE TS IN THE FCST FOR SATURDAY AFTERNOON INTO
SATURDAY NIGHT.
WINDS WILL REMAIN STRONGER ON THE ORDER OF 15 TO 20KTS OUT OF THE W
BEHIND THE COLD FRONT AS THE SFC LOW SHIFTS FROM NEAR LAKE WINNIPEG
AT 12Z SATURDAY...TO NORTHERN ONTARIO/HUDSON BAY ON SUNDAY. NO
SIGNIFICANT WARM UP IS IN SIGHT...WITH 850MB TEMPS HOVERING AROUND
0C SUNDAY WITH TEMPS FALLING TO AROUND -8C MONDAY AFTERNOON ON N-NW
WINDS OFF LAKE SUPERIOR. DID NOT GO WITH FALLING SFC TEMPS FOR
MONDAY QUITE YET...EVEN THOUGH BOTH THE GFS AND ECMWF LOOK FAIRLY
CONSISTENT WITH THIS IDEA. AS NOTED IN THE PREVIOUS
DISCUSSION...WRAP AROUND MOISTURE LOOKS TO BET BEHIND THE
LOW...PARTICULARLY IN NW FLOW OFF LAKE SUPERIOR CAN LINGER OVER THE
CWA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 149 PM EDT TUE APR 3 2012
LOW PRESSURE TROUGH HOVERING JUST EAST OF UPPER MICHIGAN WILL SLOWLY
EXIT EASTWARD THROUGH THE TAF PERIOD. DRY AIR OBSERVED ON
INTERNATIONAL FALLS SOUNDING IS STEADILY EATING AWAY AT THE MORE
EXTENSIVE CLOUD DECK. CLOUD COVER IS LINGERING OVER THE WEST...AT
KCMX AND KIWD ASSOCIATED WITH LINGERING MOISTURE AND SOME LOCALIZED
CONVERGENCE. THROUGH THE AFTERNOON...CLOUD COVER SHOULD GRADUALLY
BECOME MORE SCATTERED AS OPPOSED TO THE BKN TO OVC SKIES THE SITES
HAVE SEEN ALL MORNING. WOULD NOT BE SURPRISED IF THE BKN DECK AT
KIWD DISSIPATED A LITTLE EARLIER THAN INDICATED IN THE TAFS...AND
WILL AMEND ACCORDINGLY. WEBCAMS NEAR BESSEMER SHOW THE CLOUD
COVERAGE BECOMING SCT IN NATURE...BUT HOUGHTON CAMERAS STILL SHOW A
MORE SOLID DECK. OVERNIGHT EXPECT SKIES TO BE CLEAR...REMAINING
THROUGH MID AFTERNOON TOMORROW. DAYTIME CUMULUS IS POSSIBLE AT KCMX
AND KSAW WITH HEATING AND ADDED MOISTURE FROM NORTHERLY TO
NORTHEASTERLY WINDS OFF LAKE SUPERIOR. OVERALL...THE TREND WILL BE
TOWARDS VFR FOR ALL THREE SITES.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 533 AM EDT TUE APR 3 2012
WINDS SHOULD REMAIN LESS THAN 30KTS THROUGH THE PERIOD...GETTING
NEAR THIS LEVEL W AND CENTRAL SUNDAY AFTERNOON OFF WSW WINDS. IN THE
SHORTER TERM...A TROUGH OF LOW PRESSURE OVER CENTRAL AND EASTERN
LAKE SUPERIOR WILL EXIT ACROSS LAKE HURON THIS EVENING. THIS WILL
MAKE WAY FOR LARGE HIGH PRESSURE OVER CENTRAL CANADA AND THE
NORTHERN PLAINS TO SHIFT DIRECTLY OVER THE UPPER GREAT LAKES
WEDNESDAY AFTERNOON...WHERE IT WILL REMAIN THROUGH FRIDAY. A LOW
DEVELOPING OVER MANITOBA AND NORTH DAKOTA SATURDAY MORNING WILL
SLIDE OVER NORTHERN LAKE SUPERIOR AND ONTARIO SATURDAY NIGHT INTO
SUNDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLA
SHORT TERM...JLA
LONG TERM...KF
AVIATION...MCB
MARINE...KF
AREA FORECAST DISCUSSION
NWS GAYLORD MI
101 PM EDT TUE APR 3 2012
.SYNOPSIS...
HIGH PRESSURE OVER CENTRAL CANADA...WILL EXTEND INTO THE REGION
TONIGHT...BEFORE SLIDING INTO THE GREAT LAKES LATER THIS WEEK. THIS
PATTERN WILL BRING FAIR WEATHER TO NORTHERN MICHIGAN FOR THE NEXT
SEVERAL DAYS...WITH HIGH AND LOW TEMPERATURES NEAR TO SLIGHTLY ABOVE
AVERAGE. THE NEXT CHANCE OF RAIN WILL HOLD OFF UNTIL SATURDAY NIGHT
INTO SUNDAY...AS A COLD FRONT MOVES THROUGH THE GREAT LAKES.
&&
.UPDATE...
ISSUED AT 1242 PM EDT TUE APR 3 2012
THE CLOUDY DAY CONTINUES ACROSS NRN MICHIGAN...BUT THE CLEARING
LINE IS SET TO ARRIVE LATE THIS AFTERNOON. BETWEEN 4-6PM...MOST
ALL OF EASTERN UPPER WILL HAVE BEEN CLEARED OUT...AND THEN 6PM TO
9PM FOR NRN LOWER. THIS CLEARING IS MAKING STEADY PROGRESS FROM
WNW-ESE. THERE HAS BEEN SOME DIURNAL STRATO CU BEHIND IT...BUT BY
THE TIME IT GETS HERE...SLOW LOSS OF DIURNAL HEATING OUGHT TO
LIMIT THAT HERE. TEMPERATURES NOT TO DO MUCH THROUGH THE DAY DUE
TO CLOUDS AND SLIGHT COOL ADVECTION...STILL ON TRACK FOR A SLOW
CLIMB INTO THE UPPER 40S AND LOWER HALF OF THE 50S. NO ADDITIONAL
UPDATES NEEDED.
UPDATE ISSUED AT 1036 AM EDT TUE APR 3 2012
SHARPENING SHORTWAVE WORKING INTO ONTARIO CONTINUES TO FLATTEN
THE UPPER RIDGE OVERHEAD...AS LOW LEVEL TROUGHING TRACKS TOWARD
EASTERN UPPER. THERE HAVE BEEN A FEW REPORTS OF SOME VERY LIGHT
RAIN OR DRIZZLE ASSOCIATED WITH THE TROUGH. THIS TROUGH CONNECTS
BACK TO A WEAKENING AREA OF LOW PRESSURE THAT WAS SHIFTING ACROSS
ILLINOIS THIS MORNING. SFC-H8 WARM FRONT WELL SOUTH OF US ALONG
WITH THE MAIN INSTABILITY AND THUNDER POTENTIAL. REMOVED
THUNDER FROM THE FORECAST...HOWEVER...DECAYING AREA OF LIGHT
SHOWERS CONTINUES TO TRACK ACROSS ARENAC/GLADWIN COUNTIES. THIS
PRECIPITATION WILL BE GONE IN THE NEXT HOUR. WE WILL THEN BE
AWAITING UPSTREAM TROUGHING TO BRING IN SMALL CHANCE/PATCHY AREAS
OF LIGHT RAIN/DRIZZLE. CHANCES LIKELY SMALLER THAN THAT...AS
CONVERGENCE ASSOCIATED WITH THE TROUGH WANES...AS SOUTHERLY WINDS
AHEAD OF IT WILL ALREADY BE TURNING AROUND OUT OF THE NORTH WITH
PASSAGE OF LOW PRESSURE IN ILLINOIS. RATHER CLOUDY THROUGH MUCH OF
THE DAY. VERY DRY AIR RETURNS TO EASTERN UPPER IN THE MID
AFTERNOON HOURS...AND THEN LATE AFTERNOON/EVENING IN NRN LOWER.
TEMPERATURES LOOKED REASONABLE WITH THE ONLY CHANGE WAS TO
INCREASE HIGHS IN EASTERN UPPER DUE TO A BIT MORE SUNSHINE
EXPECTED.
UPDATE ISSUED AT 811 AM EDT TUE APR 3 2012
INITIAL BATCH OF SHWRS EXITED INTO LAKE HURON BY 6 AM. THE ENHANCED
STRATIFORM AREA OF -RA WAS OVER LAKE MI AND WILL MOVE INTO NW
LOWER MI IN THE NEXT HOUR. SINCE MCS WAS OVER CENTRAL WI AT TIME
OF 313 AM FCST ISSUANCE...UNCERTAINTY HAS DIMINISHED ON ITS
ARRIVAL. SO POPS WERE INCREASED TO 100% AND HAVE TIMED THIS THRU
NRN LOWER PENINSULA. IF IT HOLDS TOGETHER...THE BACK EDGE SHOULD
BE OFFSHORE INTO LAKE HURON NO LATER THAN 2 PM.
THUNDER: THE BEST ARC OF ELEVATED INSTABILITY IS S OF M-55. BUT
THE M-55 CORRIDOR HAS THE "BEST" CHC FOR THUNDER. WE SEE THE NEW
SHWRS GOING UP OVER MANISTEE/WEXFORD COUNTIES. THAT OFFERS BETTER
POTENTIAL THAN THE STRATIFORM AREA. A TENTH OF LIQUID WAS MEASURED
AT STURGEON WI...ON THE W COAST OF LAKE MI IN THE PAST HOUR. SO A
FEW HUNDREDTHS WILL FALL.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 313 AM EDT TUE APR 3 2012
QUITE AN AMPLIFIED PATTERN ONGOING OVER THE WESTERN HEMISPHERE EARLY
THIS MORNING...WITH LARGE SCALE TROUGHS ANCHORED ALONG BOTH COASTS
OF NOAM WITH A REX BLOCK-LIKE FEATURE STUCK BETWEEN
THESE...KEEPING THE WEATHER SOMEWHAT INTERESTING OVER WHAT WOULD
OTHERWISE BE LARGE-SCALE RIDGING.
THE FOCUS FOR THE NEAR TERM AND THROUGH TODAY IS SHOWER AND
THUNDERSTORM POTENTIAL AS INVERTED TROUGH PULLS INTO THE REGION FROM
THE WEST. OVERNIGHT...SHOWERS AND THUNDERSTORMS HAVE MADE THE MOST
OF VERY MEAGER INSTABILITY...CONTINUOUSLY FIRING ALONG THE H85
MOISTURE BOUNDARY AS IT PUSHES EAST INTO THE REGION. THROUGH
DAYBREAK...I EXPECT AREAS FROM M-32 NORTH TO SEE SOME SHRA ACTIVITY
/WITH A FEW EMBEDDED RUMBLES/...WITH A FEW MORE SHOWERS DOWN NEAR
MANISTEE.
THINGS GET TRICKIER AS WE HEAD INTO THE DAY TODAY...WITH THE IMPACTS
OF ANOTHER CONVECTIVE COMPLEX NOW OVER WESTERN WISCONSIN NOT SO
CERTAIN. CORFIDI VECTORS SUGGEST THAT THIS COMPLEX WILL PUSH EAST
AND THEN SOUTHEAST...OVER THE TOP OF THE H5 RIDGE AXIS...WHICH WOULD
SUGGEST ARRIVAL NEAR MY SOUTHWEST ZONES TOWARDS 12Z. THE HRRR IS ON
BOARD WITH THIS...AS IS OUR PREVIOUS GRIDDED FORECAST AND WILL
CONTINUE EARLY MORNING LIKELY POPS BASICALLY SOUTH OF M-72 AND WEST
OF INTERSTATE 75. GIVEN THE TIME OF DAY...EXPECT THIS COMPLEX TO
DIE AS IT MOVES EAST...WITH LITTLE TO HANG YOUR HAT ON FOR FORCING
FOR THE REMAINDER OF THE DAY AS AFOREMENTIONED INVERTED TROUGH
INCREASES LOW LEVEL CONVERGENCE TO SOME EXTENT. STILL...WITH MOIST
PLUME OVERHEAD...AND CVA FROM WAVE NOW MOVING INTO WESTERN
ONTARIO...EXPECT SOME ADDITIONAL SHOWERS TO POP UP ALONG THE H85
COLD FRONT AS IT SAGS THROUGH THE REGION THIS AFTERNOON. CONFIDENCE
IS PRETTY LOW IN HOW THIS EVOLVES THIS AFTERNOON...AND THAT IS WHY
I/LL KEEP POPS IN THE CHANCE CATEGORY. TEMPERATURES LIKELY WON/T
MAKE TOO MUCH PROGRESS GIVEN CLOUD COVER. REALLY LIKED INHERITED
HIGHS IN THE LOWER 50S /WITH A FEW MID 50S OVER SOUTHERN AREAS/ AND
WILL CONTINUE THEM IN THIS PACKAGE. THIS IS TOWARDS THE COOLER END
OF THE GUIDANCE ENVELOPE.
TONIGHT...DRIER AIR PUSHES INTO THE REGION AS INVERTED TROUGH SCOOTS
TO THE SOUTHEAST OF THE AREA WITH DEEP LAYER NORTHWEST FLOW
DEVELOPING. THIS SHOULD SCOUR OUT ANY REMNANT LOW LEVEL
MOISTURE...BRINGING CLEARING SKIES. WITH WINDS LIKELY TO REMAIN
COUPLED...I DON/T EXPECT LOWS TO FALL ALL THAT FAR...WITH FAIRLY
HOMOGENEOUS VALUES NEAR OR A LITTLE ABOVE 30 EXPECTED.
WEDNESDAY...EXPANSIVE AREA OF HIGH PRESSURE BUILDS SOUTH INTO THE
HUDSON BAY REGION WITH DRY NORTHWESTERLY FLOW VEERING NORTHERLY
DURING THE DAY UNDER CONTINUED COLD ADVECTION. GIVEN VERY DRY
ARRIVING AIRMASS...EXPECT A SUNNY/MSUNNY DAY WITH AMPLE SUBSIDENCE
TO ENSURE LITTLE IN THE WAY OF CUMULUS DEVELOPMENT. WITH THE
AFOREMENTIONED SUBSIDENCE...WOULDN/T BE SURPRISED IF WE DON/T MIX
QUITE AS HIGH AS THE MODELS ARE ADVERTISING...AND UNDER COLD
ADVECTION FEEL TEMPS WILL STRUGGLE A LITTLE. THEREFORE...WILL
FOLLOW CLOSER TO THE COOLER SIDE OF THE GUIDANCE ENVELOPE /MET/ WITH
HIGHS IN THE MID 40S OVER EASTERN UPPER...TO THE LOWER 50S OVER
NORTHERN LOWER. GIVEN THE FLOW TRAJECTORIES AND SUBSIDENT
FLOW...EXPECT A VERY DRY AIRMASS WITH DEWPOINTS LIKELY TUMBLING INTO
THE UPPER TEENS BY MID/LATE AFTERNOON. THIS WILL BRING MINIMUM RH/S
INTO THE 20S. WITH GUSTY NORTH/NORTHWEST WINDS...WILL CONTINUE
ELEVATED FIRE DANGER WORDING IN THE MORNING HWO...BUT TEMPERATURES
WILL BE WELL BELOW RED FLAG LEVELS.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 313 AM EDT TUE APR 3 2012
UPPER PATTERN REMAINS ONLY VERY SLOWLY PROGRESSIVE THRU THE REST OF
THE WORK WEEK AND INTO THE WEEKEND. THAT WILL STILL EVENTUALLY BRING
THE PAC NW UPPER TROF EASTWARD INTO OUR REGION...BUT LIKELY NOT
UNTIL THE END OF THE WEEKEND. BEFORE THEN...THURSDAY/FRIDAY/SATURDAY
CONTINUE TO LOOK RELATIVELY UNEVENTFUL...WITH SURFACE HIGH PRESSURE
ENTRENCHED IN THE GREAT LAKES REGION.
WED NIGHT-SAT...A REASONABLY VIGOROUS SHORTWAVE DROPS SOUTH ACROSS
THE NORTHERN LAKES WED NIGHT. THIS SYSTEM IS MOISTURE-STARVED...AND
WILL BRING NO MORE THAN SOME MID-HIGH CLOUDS...PRIMARILY TO EASTERN
UPPER AND NE LOWER MI. HOWEVER...IT WILL PUSH A SECONDARY COLD FRONT
ACROSS THE AREA...HELPING TO MAINTAIN 850MB TEMPS IN THE -6 TO -8C
RANGE BY THU MORNING. WARM ADVECTION (ON N TO NE LOW LEVEL FLOW) AND
AIRMASS MODIFICATION BEGIN SHORTLY THEREAFTER. BUT WE WILL STILL SEE
SOMEWHAT COOLISH TEMPS...ESPECIALLY WED NIGHT AND THU NIGHT. EXPECT
MINS MAINLY IN THE 20S...AND COULD DEFINITELY SEE TEENS IN THE USUAL
COLD INTERIOR LOCALES. GIVEN OUR EARLY START TO THE GROWING
SEASON...FROST/FREEZE HEADLINES COULD WELL BE NEEDED ON BOTH NIGHTS.
WE/LL SEE ENOUGH SUN TO KEEP MAX TEMPS RESPECTABLE THURSDAY...MID
40S TO AROUND 50. RH LEVELS WILL BE PRETTY LOW DESPITE THE COOLISH
TEMPS...WITH DEW POINTS IN THE TEENS (PERHAPS LOWER) AT PEAK HEATING.
FOR NOW...IT LOOKS LIKE WE WON/T QUITE HAVE ENOUGH OF A NORTHERLY
BREEZE TO MAKE FOR AN ENHANCED FIRE THREAT DAY.
HIGH PRESSURE MOVES OVERHEAD BY FRIDAY...AND THE AIRMASS WILL
CONTINUE TO MODERATE. MAX TEMPS WILL JUMP INTO THE 50S FRIDAY...AND
WILL APPROACH 60F IN SPOTS SATURDAY...WITH PLENTY OF SUNSHINE. AFTER
A DAY WITH HARDLY ANY WIND FRIDAY...A DEVELOPING SOUTHERLY BREEZE
SATURDAY COULD ALSO PRODUCE AN ENHANCED FIRE THREAT...THOUGH FOR NOW
(LIKE THURSDAY) FORECAST WINDS AREN/T QUITE STRONG ENOUGH.
LATER PERIODS...TIMING AGREEMENT REMAINS DECENT ON LOW PRESSURE
LIFTING TOWARD HUDSON BAY SAT NIGHT/SUNDAY...AND AN ASSOCIATED COLD
FRONT CROSSING MI LATE SAT NIGHT/SUNDAY MORNING. CHANCE POPS STILL
IN ORDER WAY OUT THEN. DEPENDING ON YOUR MODEL SOLUTION OF CHOICE...
MAY HAVE ENOUGH COOL AIR AND DEEP CYCLONIC FLOW TO PRODUCE A CHANCE
FOR RAIN/SNOW SHOWERS ON MONDAY. THE OPERATIONAL GFS IS AMONGST
THE CHILLIEST/MOST MOIST BY MONDAY...IT HAS BEEN KNOWN TO OVERDUE
THESE SORTS OF THINGS FROM TIME TO TIME.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1242 PM EDT TUE APR 3 2012
VFR OVC CIGS THROUGH ALMOST ALL OF THE AFTERNOON. TROUGHING
CONTINUES TO DROP INTO NRN MICHIGAN WITH WIDESPREAD CLOUDS. THE
CLEARING LINE IS WORKING IT`S WAY TOWARD EASTERN UPPER
MICHIGAN...SET TO MAKE AN ARRIVAL AT PLN AROUND 23Z...WITH THE
OTHER AIRPORTS 1-2 HOURS AFTER. STRONG LOW LEVEL DRYING WILL LEAD
TO CLEAR SKIES FOR THE NIGHT. NOT COLD ENOUGH FOR ANY SHALLOW
CLOUDS OFF THE LAKE...PLUS WAY TOO DRY. MAYBE A TOUCH OF SHALLOW
CU TOMORROW...BUT DOUBT IT. VFR THROUGH THE TAF PERIOD. VERY VERY
MARGINAL LLWS FOR TONIGHT...AS THERE SHOULD AT LEAST BE A 3-5KT
WIND WITH 20-25KTS ALOFT.
&&
.MARINE...
ISSUED AT 1242 PM EDT TUE APR 3 2012
NW WINDS DEVELOPING BEHIND LOW LEVEL TROUGHING WORKING THROUGH NRN
MICHIGAN...WILL INCREASE TO 20-30KTS...STRONGEST ACROSS WHITEFISH
BAY AND PRESQUE ISLE. NEAR NEUTRAL/SLIGHTLY UNSTABLE AIR JUST OFF
THE WATER SURFACE WILL LEAD TO SMALL CRAFT ADVISORY GUSTS FOR THE
ISSUANCE OF THOSE ADVISORIES AT WHITEFISH AND PRESQUE ISLE THROUGH
TOMORROW. MAYBE A COUPLE MORE NEEDED. WINDS DO VEER AROUND TO OUT
OF THE NORTHEAST WEDNESDAY NIGHT...AND ONLY LIGHTEN UP A SLIGHT
BIT...BUT ADVISORIES NOT EXPECTED.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...SMALL CRAFT ADVISORY FROM 5 PM THIS AFTERNOON TO 5 PM EDT
WEDNESDAY FOR LHZ347-348.
LM...NONE.
LS...SMALL CRAFT ADVISORY FROM 5 PM THIS AFTERNOON TO 5 PM EDT
WEDNESDAY FOR LSZ321.
&&
$$
UPDATE...SD
SYNOPSIS...NS
SHORT TERM...JA
LONG TERM....JZ
AVIATION...SD
MARINE...SD
AREA FORECAST DISCUSSION
NWS GAYLORD MI
1046 AM EDT TUE APR 3 2012
.SYNOPSIS...
A WEAK COLD FRONT WILL CROSS NORTHERN MICHIGAN THIS MORNING AND
EARLY IN THE AFTERNOON. RAIN CHANCES WILL END BY THIS EVENING.
AFTER THAT...HIGH PRESSURE WILL MOVE SOUTH OUT OF CENTRAL CANADA.
THIS WILL PROVIDE QUIET WEATHER...WITH A SERIES OF CHILLY NIGHTS BUT
RELATIVELY MILD DAYS. OUR NEXT CHANCE FOR RAIN WILL WAIT UNTIL
SATURDAY NIGHT AND SUNDAY.
&&
.UPDATE...
ISSUED AT 1036 AM EDT TUE APR 3 2012
SHARPENING SHORTWAVE WORKING INTO ONTARIO CONTINUES TO FLATTEN
THE UPPER RIDGE OVERHEAD...AS LOW LEVEL TROUGHING TRACKS TOWARD
EASTERN UPPER. THERE HAVE BEEN A FEW REPORTS OF SOME VERY LIGHT
RAIN OR DRIZZLE ASSOCIATED WITH THE TROUGH. THIS TROUGH CONNECTS
BACK TO A WEAKENING AREA OF LOW PRESSURE THAT WAS SHIFTING ACROSS
ILLINOIS THIS MORNING. SFC-H8 WARM FRONT WELL SOUTH OF US ALONG
WITH THE MAIN INSTABILITY AND THUNDER POTENTIAL. REMOVED
THUNDER FROM THE FORECAST...HOWEVER...DECAYING AREA OF LIGHT
SHOWERS CONTINUES TO TRACK ACROSS ARENAC/GLADWIN COUNTIES. THIS
PRECIPITATION WILL BE GONE IN THE NEXT HOUR. WE WILL THEN BE
AWAITING UPSTREAM TROUGHING TO BRING IN SMALL CHANCE/PATCHY AREAS
OF LIGHT RAIN/DRIZZLE. CHANCES LIKELY SMALLER THAN THAT...AS
CONVERGENCE ASSOCIATED WITH THE TROUGH WANES...AS SOUTHERLY WINDS
AHEAD OF IT WILL ALREADY BE TURNING AROUND OUT OF THE NORTH WITH
PASSAGE OF LOW PRESSURE IN ILLINOIS. RATHER CLOUDY THROUGH MUCH OF
THE DAY. VERY DRY AIR RETURNS TO EASTERN UPPER IN THE MID
AFTERNOON HOURS...AND THEN LATE AFTERNOON/EVENING IN NRN LOWER.
TEMPERATURES LOOKED REASONABLE WITH THE ONLY CHANGE WAS TO
INCREASE HIGHS IN EASTERN UPPER DUE TO A BIT MORE SUNSHINE
EXPECTED.
UPDATE ISSUED AT 811 AM EDT TUE APR 3 2012
INITIAL BATCH OF SHWRS EXITED INTO LAKE HURON BY 6 AM. THE ENHANCED
STRATIFORM AREA OF -RA WAS OVER LAKE MI AND WILL MOVE INTO NW
LOWER MI IN THE NEXT HOUR. SINCE MCS WAS OVER CENTRAL WI AT TIME
OF 313 AM FCST ISSUANCE...UNCERTAINTY HAS DIMINISHED ON ITS
ARRIVAL. SO POPS WERE INCREASED TO 100% AND HAVE TIMED THIS THRU
NRN LOWER PENINSULA. IF IT HOLDS TOGETHER...THE BACK EDGE SHOULD
BE OFFSHORE INTO LAKE HURON NO LATER THAN 2 PM.
THUNDER: THE BEST ARC OF ELEVATED INSTABILITY IS S OF M-55. BUT
THE M-55 CORRIDOR HAS THE "BEST" CHC FOR THUNDER. WE SEE THE NEW
SHWRS GOING UP OVER MANISTEE/WEXFORD COUNTIES. THAT OFFERS BETTER
POTENTIAL THAN THE STRATIFORM AREA. A TENTH OF LIQUID WAS MEASURED
AT STURGEON WI...ON THE W COAST OF LAKE MI IN THE PAST HOUR. SO A
FEW HUNDREDTHS WILL FALL.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 313 AM EDT TUE APR 3 2012
QUITE AN AMPLIFIED PATTERN ONGOING OVER THE WESTERN HEMISPHERE EARLY
THIS MORNING...WITH LARGE SCALE TROUGHS ANCHORED ALONG BOTH COASTS
OF NOAM WITH A REX BLOCK-LIKE FEATURE STUCK BETWEEN
THESE...KEEPING THE WEATHER SOMEWHAT INTERESTING OVER WHAT WOULD
OTHERWISE BE LARGE-SCALE RIDGING.
THE FOCUS FOR THE NEAR TERM AND THROUGH TODAY IS SHOWER AND
THUNDERSTORM POTENTIAL AS INVERTED TROUGH PULLS INTO THE REGION FROM
THE WEST. OVERNIGHT...SHOWERS AND THUNDERSTORMS HAVE MADE THE MOST
OF VERY MEAGER INSTABILITY...CONTINUOUSLY FIRING ALONG THE H85
MOISTURE BOUNDARY AS IT PUSHES EAST INTO THE REGION. THROUGH
DAYBREAK...I EXPECT AREAS FROM M-32 NORTH TO SEE SOME SHRA ACTIVITY
/WITH A FEW EMBEDDED RUMBLES/...WITH A FEW MORE SHOWERS DOWN NEAR
MANISTEE.
THINGS GET TRICKIER AS WE HEAD INTO THE DAY TODAY...WITH THE IMPACTS
OF ANOTHER CONVECTIVE COMPLEX NOW OVER WESTERN WISCONSIN NOT SO
CERTAIN. CORFIDI VECTORS SUGGEST THAT THIS COMPLEX WILL PUSH EAST
AND THEN SOUTHEAST...OVER THE TOP OF THE H5 RIDGE AXIS...WHICH WOULD
SUGGEST ARRIVAL NEAR MY SOUTHWEST ZONES TOWARDS 12Z. THE HRRR IS ON
BOARD WITH THIS...AS IS OUR PREVIOUS GRIDDED FORECAST AND WILL
CONTINUE EARLY MORNING LIKELY POPS BASICALLY SOUTH OF M-72 AND WEST
OF INTERSTATE 75. GIVEN THE TIME OF DAY...EXPECT THIS COMPLEX TO
DIE AS IT MOVES EAST...WITH LITTLE TO HANG YOUR HAT ON FOR FORCING
FOR THE REMAINDER OF THE DAY AS AFOREMENTIONED INVERTED TROUGH
INCREASES LOW LEVEL CONVERGENCE TO SOME EXTENT. STILL...WITH MOIST
PLUME OVERHEAD...AND CVA FROM WAVE NOW MOVING INTO WESTERN
ONTARIO...EXPECT SOME ADDITIONAL SHOWERS TO POP UP ALONG THE H85
COLD FRONT AS IT SAGS THROUGH THE REGION THIS AFTERNOON. CONFIDENCE
IS PRETTY LOW IN HOW THIS EVOLVES THIS AFTERNOON...AND THAT IS WHY
I/LL KEEP POPS IN THE CHANCE CATEGORY. TEMPERATURES LIKELY WON/T
MAKE TOO MUCH PROGRESS GIVEN CLOUD COVER. REALLY LIKED INHERITED
HIGHS IN THE LOWER 50S /WITH A FEW MID 50S OVER SOUTHERN AREAS/ AND
WILL CONTINUE THEM IN THIS PACKAGE. THIS IS TOWARDS THE COOLER END
OF THE GUIDANCE ENVELOPE.
TONIGHT...DRIER AIR PUSHES INTO THE REGION AS INVERTED TROUGH SCOOTS
TO THE SOUTHEAST OF THE AREA WITH DEEP LAYER NORTHWEST FLOW
DEVELOPING. THIS SHOULD SCOUR OUT ANY REMNANT LOW LEVEL
MOISTURE...BRINGING CLEARING SKIES. WITH WINDS LIKELY TO REMAIN
COUPLED...I DON/T EXPECT LOWS TO FALL ALL THAT FAR...WITH FAIRLY
HOMOGENEOUS VALUES NEAR OR A LITTLE ABOVE 30 EXPECTED.
WEDNESDAY...EXPANSIVE AREA OF HIGH PRESSURE BUILDS SOUTH INTO THE
HUDSON BAY REGION WITH DRY NORTHWESTERLY FLOW VEERING NORTHERLY
DURING THE DAY UNDER CONTINUED COLD ADVECTION. GIVEN VERY DRY
ARRIVING AIRMASS...EXPECT A SUNNY/MSUNNY DAY WITH AMPLE SUBSIDENCE
TO ENSURE LITTLE IN THE WAY OF CUMULUS DEVELOPMENT. WITH THE
AFOREMENTIONED SUBSIDENCE...WOULDN/T BE SURPRISED IF WE DON/T MIX
QUITE AS HIGH AS THE MODELS ARE ADVERTISING...AND UNDER COLD
ADVECTION FEEL TEMPS WILL STRUGGLE A LITTLE. THEREFORE...WILL
FOLLOW CLOSER TO THE COOLER SIDE OF THE GUIDANCE ENVELOPE /MET/ WITH
HIGHS IN THE MID 40S OVER EASTERN UPPER...TO THE LOWER 50S OVER
NORTHERN LOWER. GIVEN THE FLOW TRAJECTORIES AND SUBSIDENT
FLOW...EXPECT A VERY DRY AIRMASS WITH DEWPOINTS LIKELY TUMBLING INTO
THE UPPER TEENS BY MID/LATE AFTERNOON. THIS WILL BRING MINIMUM RH/S
INTO THE 20S. WITH GUSTY NORTH/NORTHWEST WINDS...WILL CONTINUE
ELEVATED FIRE DANGER WORDING IN THE MORNING HWO...BUT TEMPERATURES
WILL BE WELL BELOW RED FLAG LEVELS.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 313 AM EDT TUE APR 3 2012
UPPER PATTERN REMAINS ONLY VERY SLOWLY PROGRESSIVE THRU THE REST OF
THE WORK WEEK AND INTO THE WEEKEND. THAT WILL STILL EVENTUALLY BRING
THE PAC NW UPPER TROF EASTWARD INTO OUR REGION...BUT LIKELY NOT
UNTIL THE END OF THE WEEKEND. BEFORE THEN...THURSDAY/FRIDAY/SATURDAY
CONTINUE TO LOOK RELATIVELY UNEVENTFUL...WITH SURFACE HIGH PRESSURE
ENTRENCHED IN THE GREAT LAKES REGION.
WED NIGHT-SAT...A REASONABLY VIGOROUS SHORTWAVE DROPS SOUTH ACROSS
THE NORTHERN LAKES WED NIGHT. THIS SYSTEM IS MOISTURE-STARVED...AND
WILL BRING NO MORE THAN SOME MID-HIGH CLOUDS...PRIMARILY TO EASTERN
UPPER AND NE LOWER MI. HOWEVER...IT WILL PUSH A SECONDARY COLD FRONT
ACROSS THE AREA...HELPING TO MAINTAIN 850MB TEMPS IN THE -6 TO -8C
RANGE BY THU MORNING. WARM ADVECTION (ON N TO NE LOW LEVEL FLOW) AND
AIRMASS MODIFICATION BEGIN SHORTLY THEREAFTER. BUT WE WILL STILL SEE
SOMEWHAT COOLISH TEMPS...ESPECIALLY WED NIGHT AND THU NIGHT. EXPECT
MINS MAINLY IN THE 20S...AND COULD DEFINITELY SEE TEENS IN THE USUAL
COLD INTERIOR LOCALES. GIVEN OUR EARLY START TO THE GROWING
SEASON...FROST/FREEZE HEADLINES COULD WELL BE NEEDED ON BOTH NIGHTS.
WE/LL SEE ENOUGH SUN TO KEEP MAX TEMPS RESPECTABLE THURSDAY...MID
40S TO AROUND 50. RH LEVELS WILL BE PRETTY LOW DESPITE THE COOLISH
TEMPS...WITH DEW POINTS IN THE TEENS (PERHAPS LOWER) AT PEAK HEATING.
FOR NOW...IT LOOKS LIKE WE WON/T QUITE HAVE ENOUGH OF A NORTHERLY
BREEZE TO MAKE FOR AN ENHANCED FIRE THREAT DAY.
HIGH PRESSURE MOVES OVERHEAD BY FRIDAY...AND THE AIRMASS WILL
CONTINUE TO MODERATE. MAX TEMPS WILL JUMP INTO THE 50S FRIDAY...AND
WILL APPROACH 60F IN SPOTS SATURDAY...WITH PLENTY OF SUNSHINE. AFTER
A DAY WITH HARDLY ANY WIND FRIDAY...A DEVELOPING SOUTHERLY BREEZE
SATURDAY COULD ALSO PRODUCE AN ENHANCED FIRE THREAT...THOUGH FOR NOW
(LIKE THURSDAY) FORECAST WINDS AREN/T QUITE STRONG ENOUGH.
LATER PERIODS...TIMING AGREEMENT REMAINS DECENT ON LOW PRESSURE
LIFTING TOWARD HUDSON BAY SAT NIGHT/SUNDAY...AND AN ASSOCIATED COLD
FRONT CROSSING MI LATE SAT NIGHT/SUNDAY MORNING. CHANCE POPS STILL
IN ORDER WAY OUT THEN. DEPENDING ON YOUR MODEL SOLUTION OF CHOICE...
MAY HAVE ENOUGH COOL AIR AND DEEP CYCLONIC FLOW TO PRODUCE A CHANCE
FOR RAIN/SNOW SHOWERS ON MONDAY. THE OPERATIONAL GFS IS AMONGST
THE CHILLIEST/MOST MOIST BY MONDAY...IT HAS BEEN KNOWN TO OVERDUE
THESE SORTS OF THINGS FROM TIME TO TIME.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 811 AM EDT TUE APR 3 2012
TODAY: ONE-HOUR BATCH OF VFR -RA WILL ADVANCE ACROSS THE TAF
SITES. CLOUDS WILL BE MULTI-LAYERED. WINDS WILL BE LIGHT FROM THE
SE THRU 17Z /THO AT TIMES VARIABLE DIR/. THEN AN ABRUPT WSHFT TO
WNW-NW WITH AN INCREASE TO 10 KTS WITH SOME GUSTINESS TO 16 KTS.
PKWND COULD BE AS HIGH AS 20 KTS BRIEFLY. AFTER WSHFT...THERE IS
SOME POTENTIAL FOR A 1-3 HOUR WINDOW OF MVFR CIGS. THEY OVER
CURRENTLY OVER NW WI...BUT CONFIDENCE IS NOT HIGH ENUF TO INCLUDE
IN THIS TAF ISSUANCE.
TNGT: RAPID CLEARING 23-01Z. LIGHT NW WINDS 5 KTS OR LESS.
&&
.MARINE...
ISSUED AT 313 AM EDT TUE APR 3 2012
WINDS/WAVES LOOK TO GENERALLY REMAIN BELOW LEVELS HAZARDOUS TO SMALL
CRAFT THROUGH TUESDAY NIGHT AS TROUGH OF LOW PRESSURE MOVES THROUGH
THE REGION TODAY WITH NORTHWESTERLY WINDS DEVELOPING LATE THIS
AFTERNOON AND TONIGHT. THESE NORTHWESTERLY WINDS WILL STRENGTHEN ON
WEDNESDAY AS CANADIAN HIGH PRESSURE BUILDS TOWARDS THE REGION. THIS
WILL LIKELY BRING A PERIOD OF SMALL CRAFT CONDITIONS ON WEDNESDAY
BEFORE THE AFORMENTIONED HIGH SETTLES OVERHEAD WITH QUIET CONDITIONS
FOR THE END OF THE WEEK.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...SD
SYNOPSIS...JZ
SHORT TERM...JA
LONG TERM....JZ
AVIATION...HALBLAUB
MARINE...JA
AREA FORECAST DISCUSSION
NWS GAYLORD MI
811 AM EDT TUE APR 3 2012
.SYNOPSIS...
A WEAK COLD FRONT WILL CROSS NORTHERN MICHIGAN THIS MORNING AND
EARLY IN THE AFTERNOON. RAIN CHANCES WILL END BY THIS EVENING.
AFTER THAT...HIGH PRESSURE WILL MOVE SOUTH OUT OF CENTRAL CANADA.
THIS WILL PROVIDE QUIET WEATHER...WITH A SERIES OF CHILLY NIGHTS BUT
RELATIVELY MILD DAYS. OUR NEXT CHANCE FOR RAIN WILL WAIT UNTIL
SATURDAY NIGHT AND SUNDAY.
&&
.UPDATE...
ISSUED AT 811 AM EDT TUE APR 3 2012
INITIAL BATCH OF SHWRS EXITED INTO LAKE HURON BY 6 AM. THE ENHANCED
STRATIFORM AREA OF -RA WAS OVER LAKE MI AND WILL MOVE INTO NW
LOWER MI IN THE NEXT HOUR. SINCE MCS WAS OVER CENTRAL WI AT TIME
OF 313 AM FCST ISSUANCE...UNCERTAINTY HAS DIMINISHED ON ITS
ARRIVAL. SO POPS WERE INCREASED TO 100% AND HAVE TIMED THIS THRU
NRN LOWER PENINSULA. IF IT HOLDS TOGETHER...THE BACK EDGE SHOULD
BE OFFSHORE INTO LAKE HURON NO LATER THAN 2 PM.
THUNDER: THE BEST ARC OF ELEVATED INSTABILITY IS S OF M-55. BUT
THE M-55 CORRIDOR HAS THE "BEST" CHC FOR THUNDER. WE SEE THE NEW
SHWRS GOING UP OVER MANISTEE/WEXFORD COUNTIES. THAT OFFERS BETTER
POTENTIAL THAN THE STRATIFORM AREA. A TENTH OF LIQUID WAS MEASURED
AT STURGEON WI...ON THE W COAST OF LAKE MI IN THE PAST HOUR. SO A
FEW HUNDREDTHS WILL FALL.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 313 AM EDT TUE APR 3 2012
QUITE AN AMPLIFIED PATTERN ONGOING OVER THE WESTERN HEMISPHERE EARLY
THIS MORNING...WITH LARGE SCALE TROUGHS ANCHORED ALONG BOTH COASTS
OF NOAM WITH A REX BLOCK-LIKE FEATURE STUCK BETWEEN
THESE...KEEPING THE WEATHER SOMEWHAT INTERESTING OVER WHAT WOULD
OTHERWISE BE LARGE-SCALE RIDGING.
THE FOCUS FOR THE NEAR TERM AND THROUGH TODAY IS SHOWER AND
THUNDERSTORM POTENTIAL AS INVERTED TROUGH PULLS INTO THE REGION FROM
THE WEST. OVERNIGHT...SHOWERS AND THUNDERSTORMS HAVE MADE THE MOST
OF VERY MEAGER INSTABILITY...CONTINUOUSLY FIRING ALONG THE H85
MOISTURE BOUNDARY AS IT PUSHES EAST INTO THE REGION. THROUGH
DAYBREAK...I EXPECT AREAS FROM M-32 NORTH TO SEE SOME SHRA ACTIVITY
/WITH A FEW EMBEDDED RUMBLES/...WITH A FEW MORE SHOWERS DOWN NEAR
MANISTEE.
THINGS GET TRICKIER AS WE HEAD INTO THE DAY TODAY...WITH THE IMPACTS
OF ANOTHER CONVECTIVE COMPLEX NOW OVER WESTERN WISCONSIN NOT SO
CERTAIN. CORFIDI VECTORS SUGGEST THAT THIS COMPLEX WILL PUSH EAST
AND THEN SOUTHEAST...OVER THE TOP OF THE H5 RIDGE AXIS...WHICH WOULD
SUGGEST ARRIVAL NEAR MY SOUTHWEST ZONES TOWARDS 12Z. THE HRRR IS ON
BOARD WITH THIS...AS IS OUR PREVIOUS GRIDDED FORECAST AND WILL
CONTINUE EARLY MORNING LIKELY POPS BASICALLY SOUTH OF M-72 AND WEST
OF INTERSTATE 75. GIVEN THE TIME OF DAY...EXPECT THIS COMPLEX TO
DIE AS IT MOVES EAST...WITH LITTLE TO HANG YOUR HAT ON FOR FORCING
FOR THE REMAINDER OF THE DAY AS AFOREMENTIONED INVERTED TROUGH
INCREASES LOW LEVEL CONVERGENCE TO SOME EXTENT. STILL...WITH MOIST
PLUME OVERHEAD...AND CVA FROM WAVE NOW MOVING INTO WESTERN
ONTARIO...EXPECT SOME ADDITIONAL SHOWERS TO POP UP ALONG THE H85
COLD FRONT AS IT SAGS THROUGH THE REGION THIS AFTERNOON. CONFIDENCE
IS PRETTY LOW IN HOW THIS EVOLVES THIS AFTERNOON...AND THAT IS WHY
I/LL KEEP POPS IN THE CHANCE CATEGORY. TEMPERATURES LIKELY WON/T
MAKE TOO MUCH PROGRESS GIVEN CLOUD COVER. REALLY LIKED INHERITED
HIGHS IN THE LOWER 50S /WITH A FEW MID 50S OVER SOUTHERN AREAS/ AND
WILL CONTINUE THEM IN THIS PACKAGE. THIS IS TOWARDS THE COOLER END
OF THE GUIDANCE ENVELOPE.
TONIGHT...DRIER AIR PUSHES INTO THE REGION AS INVERTED TROUGH SCOOTS
TO THE SOUTHEAST OF THE AREA WITH DEEP LAYER NORTHWEST FLOW
DEVELOPING. THIS SHOULD SCOUR OUT ANY REMNANT LOW LEVEL
MOISTURE...BRINGING CLEARING SKIES. WITH WINDS LIKELY TO REMAIN
COUPLED...I DON/T EXPECT LOWS TO FALL ALL THAT FAR...WITH FAIRLY
HOMOGENEOUS VALUES NEAR OR A LITTLE ABOVE 30 EXPECTED.
WEDNESDAY...EXPANSIVE AREA OF HIGH PRESSURE BUILDS SOUTH INTO THE
HUDSON BAY REGION WITH DRY NORTHWESTERLY FLOW VEERING NORTHERLY
DURING THE DAY UNDER CONTINUED COLD ADVECTION. GIVEN VERY DRY
ARRIVING AIRMASS...EXPECT A SUNNY/MSUNNY DAY WITH AMPLE SUBSIDENCE
TO ENSURE LITTLE IN THE WAY OF CUMULUS DEVELOPMENT. WITH THE
AFOREMENTIONED SUBSIDENCE...WOULDN/T BE SURPRISED IF WE DON/T MIX
QUITE AS HIGH AS THE MODELS ARE ADVERTISING...AND UNDER COLD
ADVECTION FEEL TEMPS WILL STRUGGLE A LITTLE. THEREFORE...WILL
FOLLOW CLOSER TO THE COOLER SIDE OF THE GUIDANCE ENVELOPE /MET/ WITH
HIGHS IN THE MID 40S OVER EASTERN UPPER...TO THE LOWER 50S OVER
NORTHERN LOWER. GIVEN THE FLOW TRAJECTORIES AND SUBSIDENT
FLOW...EXPECT A VERY DRY AIRMASS WITH DEWPOINTS LIKELY TUMBLING INTO
THE UPPER TEENS BY MID/LATE AFTERNOON. THIS WILL BRING MINIMUM RH/S
INTO THE 20S. WITH GUSTY NORTH/NORTHWEST WINDS...WILL CONTINUE
ELEVATED FIRE DANGER WORDING IN THE MORNING HWO...BUT TEMPERATURES
WILL BE WELL BELOW RED FLAG LEVELS.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 313 AM EDT TUE APR 3 2012
UPPER PATTERN REMAINS ONLY VERY SLOWLY PROGRESSIVE THRU THE REST OF
THE WORK WEEK AND INTO THE WEEKEND. THAT WILL STILL EVENTUALLY BRING
THE PAC NW UPPER TROF EASTWARD INTO OUR REGION...BUT LIKELY NOT
UNTIL THE END OF THE WEEKEND. BEFORE THEN...THURSDAY/FRIDAY/SATURDAY
CONTINUE TO LOOK RELATIVELY UNEVENTFUL...WITH SURFACE HIGH PRESSURE
ENTRENCHED IN THE GREAT LAKES REGION.
WED NIGHT-SAT...A REASONABLY VIGOROUS SHORTWAVE DROPS SOUTH ACROSS
THE NORTHERN LAKES WED NIGHT. THIS SYSTEM IS MOISTURE-STARVED...AND
WILL BRING NO MORE THAN SOME MID-HIGH CLOUDS...PRIMARILY TO EASTERN
UPPER AND NE LOWER MI. HOWEVER...IT WILL PUSH A SECONDARY COLD FRONT
ACROSS THE AREA...HELPING TO MAINTAIN 850MB TEMPS IN THE -6 TO -8C
RANGE BY THU MORNING. WARM ADVECTION (ON N TO NE LOW LEVEL FLOW) AND
AIRMASS MODIFICATION BEGIN SHORTLY THEREAFTER. BUT WE WILL STILL SEE
SOMEWHAT COOLISH TEMPS...ESPECIALLY WED NIGHT AND THU NIGHT. EXPECT
MINS MAINLY IN THE 20S...AND COULD DEFINITELY SEE TEENS IN THE USUAL
COLD INTERIOR LOCALES. GIVEN OUR EARLY START TO THE GROWING
SEASON...FROST/FREEZE HEADLINES COULD WELL BE NEEDED ON BOTH NIGHTS.
WE/LL SEE ENOUGH SUN TO KEEP MAX TEMPS RESPECTABLE THURSDAY...MID
40S TO AROUND 50. RH LEVELS WILL BE PRETTY LOW DESPITE THE COOLISH
TEMPS...WITH DEW POINTS IN THE TEENS (PERHAPS LOWER) AT PEAK HEATING.
FOR NOW...IT LOOKS LIKE WE WON/T QUITE HAVE ENOUGH OF A NORTHERLY
BREEZE TO MAKE FOR AN ENHANCED FIRE THREAT DAY.
HIGH PRESSURE MOVES OVERHEAD BY FRIDAY...AND THE AIRMASS WILL
CONTINUE TO MODERATE. MAX TEMPS WILL JUMP INTO THE 50S FRIDAY...AND
WILL APPROACH 60F IN SPOTS SATURDAY...WITH PLENTY OF SUNSHINE. AFTER
A DAY WITH HARDLY ANY WIND FRIDAY...A DEVELOPING SOUTHERLY BREEZE
SATURDAY COULD ALSO PRODUCE AN ENHANCED FIRE THREAT...THOUGH FOR NOW
(LIKE THURSDAY) FORECAST WINDS AREN/T QUITE STRONG ENOUGH.
LATER PERIODS...TIMING AGREEMENT REMAINS DECENT ON LOW PRESSURE
LIFTING TOWARD HUDSON BAY SAT NIGHT/SUNDAY...AND AN ASSOCIATED COLD
FRONT CROSSING MI LATE SAT NIGHT/SUNDAY MORNING. CHANCE POPS STILL
IN ORDER WAY OUT THEN. DEPENDING ON YOUR MODEL SOLUTION OF CHOICE...
MAY HAVE ENOUGH COOL AIR AND DEEP CYCLONIC FLOW TO PRODUCE A CHANCE
FOR RAIN/SNOW SHOWERS ON MONDAY. THE OPERATIONAL GFS IS AMONGST
THE CHILLIEST/MOST MOIST BY MONDAY...IT HAS BEEN KNOWN TO OVERDUE
THESE SORTS OF THINGS FROM TIME TO TIME.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 811 AM EDT TUE APR 3 2012
TODAY: ONE-HOUR BATCH OF VFR -RA WILL ADVANCE ACROSS THE TAF
SITES. CLOUDS WILL BE MULTI-LAYERED. WINDS WILL BE LIGHT FROM THE
SE THRU 17Z /THO AT TIMES VARIABLE DIR/. THEN AN ABRUPT WSHFT TO
WNW-NW WITH AN INCREASE TO 10 KTS WITH SOME GUSTINESS TO 16 KTS.
PKWND COULD BE AS HIGH AS 20 KTS BRIEFLY. AFTER WSHFT...THERE IS
SOME POTENTIAL FOR A 1-3 HOUR WINDOW OF MVFR CIGS. THEY OVER
CURRENTLY OVER NW WI...BUT CONFIDENCE IS NOT HIGH ENUF TO INCLUDE
IN THIS TAF ISSUANCE.
TNGT: RAPID CLEARING 23-01Z. LIGHT NW WINDS 5 KTS OR LESS.
&&
.MARINE...
ISSUED AT 313 AM EDT TUE APR 3 2012
WINDS/WAVES LOOK TO GENERALLY REMAIN BELOW LEVELS HAZARDOUS TO SMALL
CRAFT THROUGH TUESDAY NIGHT AS TROUGH OF LOW PRESSURE MOVES THROUGH
THE REGION TODAY WITH NORTHWESTERLY WINDS DEVELOPING LATE THIS
AFTERNOON AND TONIGHT. THESE NORTHWESTERLY WINDS WILL STRENGTHEN ON
WEDNESDAY AS CANADIAN HIGH PRESSURE BUILDS TOWARDS THE REGION. THIS
WILL LIKELY BRING A PERIOD OF SMALL CRAFT CONDITIONS ON WEDNESDAY
BEFORE THE AFORMENTIONED HIGH SETTLES OVERHEAD WITH QUIET CONDITIONS
FOR THE END OF THE WEEK.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...HALBLAUB
SYNOPSIS...JZ
SHORT TERM...JA
LONG TERM....JZ
AVIATION...HALBLAUB
MARINE...JA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
745 AM EDT TUE APR 3 2012
.SYNOPSIS...
ISSUED AT 533 AM EDT TUE APR 3 2012
RIDGE OVER THE AREA SINCE LATE IN THE WEEKEND IS BEING FLATTENED
OUT THIS MORNING AS STRONG SHORTWAVE TROUGH SLIDES FM MANITOBA INTO
NORTHWEST ONTARIO. HEIGHT FALLS ARE SUBTLE OVR UPR LAKES PER 00Z
RAOBS BUT ENOUGH TO TRIGGER MULTIPLE CLUSTERS OF SHRA/TSRA OVR THE
UPPER GREAT LAKES. FRONTAL BOUNDARY...EXTENDING SOUTH OUT OF LOW OVR
NORTHERN ONTARIO AND ALSO EXTENDING TO THE NORTH FM LOW OVR MID
MISSISSIPI RIVER VALLEY WILL CROSS UPR MICHIGAN THIS MORNING. COOLER
AIRMASS ADVECTS OVR THE AREA LATER TODAY THROUGH TONIGHT AND
WEDNESDAY. AFTER THE FROPA THIS MORNING...DRY WEATHER WILL PREVAIL
THROUGH LATE THIS WEEK AS LARGE HIGH PRESSURE IS DOMINANT WEATHER
FEATURE.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 533 AM EDT TUE APR 3 2012
TODAY...CONVECTIVE TRENDS WILL BE CHALLENGING THIS MORNING...BUT
AFTER THAT DRYING TREND WILL FIRMLY TAKE HOLD. AS OCCURRED 24 HR
AGO...MAIN AREA OF CONVECTION OVERNIGHT HAS DEVELOPED CLOSER TO H7
MOIST AXIS AND ALSO IN AREA OF H85 TEMP ADVECTION. INITIAL SHRA/TSRA
HEADING QUICKLY INTO THE FAR EAST CWA FORMED AHEAD OF ONTARIO
SHORTWAVE TROUGH AND HAVE BEHAVED FOLLOWING STEADY EASTWARD MOTION.
CONVECTION OVR MN AND WESTERN WI IS OUTLINED WELL BY WHERE RUC13
SHOWS MAXIMUM H7 MOISTURE TRANSPORT AND ON NORTHERN EDGE OF STEEPER
H7-H5 LAPSE RATES AOA 8C/KM. AT THIS TIME...MAJORITY OF TSRA ARE
OCCURRING OVR CNTRL WI BUT ADDITIONAL SHRA WITH EMBEDDED TSRA ARE
FILLING IN INTO NORTHWEST WI. FOLLOWING RUC IDEA THERE IS ENOUGH H7
MOISTURE TRANSPORT INTO SCNTRL CWA TO KEEP HIGHER POPS THERE IN THE
MORNING. A FEW SHRA/TSRA MAY EVEN CLIP AREAS FARTHER NORTH IN THE
CNTRL CWA BUT IT IS FAIRLY LIMITED CHANCE AS THE AREA OF SHRA/TSRA
OVR NORTHWEST WI WILL BE OUTRUNNING BETTER H7 MOISTURE CONVERGENCE
AND ELEVATED INSTABILITY IF THEY CONTINUE ON ENE TRACK. OVERALL
IMAGINE CHANCES OF CONVECTION WILL BEGIN TO WANE SIGNIFICANTLY OVR
MOST AREAS AFTER MID MORNING /POST 15Z-16Z/ SINCE SFC FRONT WILL BE
DROPPING S/SE OF THE AREA BY THAT TIME. HAVE HAD SOME PEA-SIZED HAIL
OVERNIGHT WITH STRONGER STORMS AND THAT REMAINS POSSIBLE THIS
MORNING GIVEN STEEP LAPSE RATES JUST UPSTREAM AND 30-35 KTS OF
EFFECTIVE SHEAR FCST OVR CNTRL PORTIONS OF UPR MI.
AS ALLUDED TO BEFORE...COLD FRONT WILL STEADILY SLIDE ACROSS THE
AREA MID TO LATE MORNING. WINDS IN WAKE OF FRONT EXPECTED TO BECOME
NORTH TO NORTHWEST. STILL APPEARS THAT THERE COULD BE BRIEF PERIOD
OF LOWER CIGS AND MAYBE SOME FOG AS HIGHER DWPNTS JUST BEHIND FRONT
SETTLE ACROSS LK SUPERIOR AND WINDS PROVIDE SOME UPSLOPE LIFTING OVR
HIGHER TERRAIN OF WESTERN AND NORTH CENTRAL CWA. POSSIBILITY FOR FOG
MAY HAVE BEEN ENHANCED DUE TO THE DECENT COVERAGE OF SHRA/TSRA OVR
LK SUPERIOR OVERNIGHT THAT MAY HAVE PROVIDED ADDITIONAL LOW-LEVEL
MOISTENING. LOOKING UPSTREAM THERE IS AREA OF LOWER CLOUDS NORTHWEST
OF LK SUPERIOR BUT THERE IS ALSO A MUCH LARGER AREA OF VERY DRY
AIR/CLEAR SKIES PUSHING ACROSS MANITOBA AND NORTHWEST ONTARIO.
REALLY HARD TO TELL AT THIS POINT HOW MUCH/IF ANY FOG IS PRESENT OVR
WESTERN LK SUPERIOR...SO WILL NOT INCLUDE IN FCST FOR LATER THIS
MORNING. EXPECT DRYING TO WIN OUT PRETTY EASILY AFTER MID AFTN ONCE
BLYR DWPNTS FALL INTO THE LOWER 30S/MID-UPR 20S AS HIGH BEGINS TO
NOSE INTO LK SUPERIOR REGION. SO SKY FCST SHAKES OUT AS FAIRLY
CLOUDY IN THE MORNING BUT WITH FAIRLY SHARP CLEARING TREND BY MID
AFTN FM WEST-TO-EAST. DESPITE THE SUNSHINE THIS AFTN...TEMPS SHOULD
BE HELD DOWN MOST AREAS WITH GRADIENT WIND FLOWING OFF LK SUPERIOR.
PROBABLY WILL SEE STEADY TEMPS ALONG LK SUPERIOR AND READINGS
PUSHING INTO LOWER 50S FAR INLAND/LK MICHIGAN SHORE WITH LESS LAKE
MODIFICATION GIVEN THE NORTHWEST WINDS. DWPNTS AND RH VALUES COULD
CRASH OVR INTERIOR WEST BY LATE AFTN. CURRENT FCST HAS RH VALUES IN
THE 30-40 PCT RANGE...BUT IF WINDS STAY MORE NW IT COULD GET WARMER
WHICH WOULD RESULT IN RH VALUES BLO 30 PCT.
VERY DRY AIRMASS BECOMES FIRMLY ENTRENCHED OVR AREA TONIGHT INTO
WEDNESDAY AS HIGH PRESSURE BUILDS FM HUDSON BAY INTO THE WESTERN
GREAT LAKES. NORTHERLY FLOW REMAINS OFF LK SUPERIOR BUT GIVEN PWATS
FALLING TOWARD 50 PCT OF NORMAL...EXPECT INTERIOR CWA TO TRY TO
DECOUPLE TONIGHT AND COOL OFF TOWARD THE LOWER DWPNTS ADVECTING INTO
THE REGION. BENEATH MOSTLY SUNNY SKIES ON WEDNESDAY...MAIN CONCERN
WILL BE ON FIRE WX WITH LOWER RH VALUES. HAVE DWPNTS IN AFTN MIXING
OUT INTO THE UPR TEENS OVR INTERIOR SECTIONS...RESULTING IN RH
VALUES BLO 30 PCT. WINDS WILL NOT BE VERY GUSTY /LEADING TO LESS
IMPACT ON FIRE WX CUSTOMERS/ BUT A STEADY NORTH WIND UP TO 15 MPH IS
EXPECTED. GIVEN THE FLOW...PROBABLY WILL HAVE TOUGH TIME REACHING 40
DEGREES ALONG LK SUPERIOR SHORE. MIXING HEIGHTS MUCH HIGHER TOWARD
WI BORDER /H85-H8 PER FCST SOUNDINGS/ ALLOW TEMPS TO RISE WELL INTO
THE 50S. OVERALL LOOKS LIKE PRETTY TYPICAL SPRING PATTERN.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 533 AM EDT TUE APR 3 2012
HIGH PRESSURE WILL DOMINATE MUCH OF THIS PERIOD. WHILE THE SFC RIDGE
WILL BE OVERHEAD AT 00Z THURSDAY...THE MAIN HIGH WILL LIKELY RESIDE
OVER HUDSON BAY AND NW ONTARIO. EXPECT THE CENTER OF HIGH PRESSURE
TO SLOWLY SIDE OVER LAKE SUPERIOR THURSDAY INTO FRIDAY. DRY AIR WILL
CONTINUE TO SLIDE INTO THE AREA FROM EASTERN ONTARIO...WITH HUMIDITY
VALUES FALLING 25 TO 25 PERCENT THURSDAY AND FRIDAY AFTERNOON AWAY
FROM THE LAKE SUPERIOR COASTLINE. ON THE PLUS SIDE...WINDS SHOULD BE
FAIRLY LIGHT...LESS THAN 10KTS AWAY FROM ANY LAKE BREEZES THAT MAY
COME IN THURSDAY AND FRIDAY AFTERNOON. STILL...IT WILL BE ENOUGH TO
INCREASE FIRE WEATHER CONCERNS OVER UPPER MICHIGAN THROUGH THE
REMAINDER OF THE WORK WEEK.
THERE WILL BE A SUBTLE CHANGE FRIDAY...AS THE HIGH PRESSURE SYSTEM
BEGINS TO SHIFT EASTWARD IN RESPONSE TO A SFC LOW ORGANIZING OVER
EASTERN WY/MT INTO THE WESTERN DAKOTAS. LOOK FOR A SLOW RETURN TO
S/SE WINDS FRIDAY INTO FRIDAY NIGHT.
THE PRESSURE GRADIENT WILL TIGHTEN OVER THE WEEKEND. EXPECT
INCREASED S/SE WINDS OF 10 TO 15KTS SATURDAY /AHEAD OF THE COLD
FRONT CROSSING SATURDAY NIGHT/. SPECIFICS FOR THIS PERIOD ARE A
LITTLE TRICKY...WITH THE BREAKDOWN OF THE 500MB RIDGE SATURDAY NIGHT
AS THE MAIN LOW REMAINS WELL TO OUR NORTH. THE 03/00Z RUN OF THE
ECMWF CONTINUES TO SHOW LIMITED MOISTURE...WITH LITTLE MORE THAN A
TRACE OF RAIN FALLING SATURDAY NIGHT AS MUCH OF THE ENERGY REMAINS
WRAPPED UP ACROSS CANADA MAINLY ON THE BACK SIDE OF THE LOW. THE
03/00Z RUN OF THE GFS ON THE OTHER HAND INDICATES THE POTENTIAL FOR
AROUND A TENTH OF AN INCH OF WELL NEEDED RAIN...WITH STILL THE BEST
CHANCE BEHIND THE LOW. GIVEN THE LOW POTENTIAL FOR EVEN RAIN...KEPT
ONLY SLIGHT CHANCE TS IN THE FCST FOR SATURDAY AFTERNOON INTO
SATURDAY NIGHT.
WINDS WILL REMAIN STRONGER ON THE ORDER OF 15 TO 20KTS OUT OF THE W
BEHIND THE COLD FRONT AS THE SFC LOW SHIFTS FROM NEAR LAKE WINNIPEG
AT 12Z SATURDAY...TO NORTHERN ONTARIO/HUDSON BAY ON SUNDAY. NO
SIGNIFICANT WARM UP IS IN SIGHT...WITH 850MB TEMPS HOVERING AROUND
0C SUNDAY WITH TEMPS FALLING TO AROUND -8C MONDAY AFTERNOON ON N-NW
WINDS OFF LAKE SUPERIOR. DID NOT GO WITH FALLING SFC TEMPS FOR
MONDAY QUITE YET...EVEN THOUGH BOTH THE GFS AND ECMWF LOOK FAIRLY
CONSISTENT WITH THIS IDEA. AS NOTED IN THE PREVIOUS
DISCUSSION...WRAP AROUND MOISTURE LOOKS TO BET BEHIND THE
LOW...PARTICULARLY IN NW FLOW OFF LAKE SUPERIOR CAN LINGER OVER THE
CWA.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 744 AM EDT TUE APR 3 2012
AREA OF SHOWERS ALONG FRONTAL BOUNDARY WILL WORK ACROSS CNTRL UPR MI
THROUGH MID MORNING AFFECTING THE SAW TAF SITE. ONCE THE FRONT
PASSES THROUGH TAF SITES EXPECT WINDS TO SHIFT TO A MORE NORTH TO
NORTHWEST DIRECTION AND FOR CIGS TO DROP TO MVFR AT IWD AND
CMX...AND POSSIBLY AT SAW AS WELL THOUGH NW WINDS ARE NOT AS
FAVORABLE. BASED ON SOME OBSERVATIONS SHOWING IFR CIGS IN NORTHERN MN
HAVE OPTED TO INCLUDE MENTION OF IFR CIGS AT CMX BY LATE MORNING
WITH UPSLOPE NORTHWEST WINDS. STILL NOT SURE IF THERE IS MUCH FOG
OVR WESTERN LK SUPERIOR...BUT IF FOG DID FORM THEN THERE COULD BE A
BRIEF PERIOD OF VSBY REDUCTION /MAYBE INTO THE IFR RANGE/ WITH THE
IFR CIGS. TOO MUCH UNCERTAINTY TO PUT THAT IN TAF ATTM...BUT CANNOT
RULE THIS OUT YET. EVENTUALLY...DEEP DRYING WILL SWEEP THROUGH ALL
TAF SITES LATE THIS AFTN WITH GUSTY NORTH WINDS. VFR CONDITIONS THEN
EXPECTED TONIGHT WITH DIMINISHING WINDS.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 533 AM EDT TUE APR 3 2012
WINDS SHOULD REMAIN LESS THAN 30KTS THROUGH THE PERIOD...GETTING
NEAR THIS LEVEL W AND CENTRAL SUNDAY AFTERNOON OFF WSW WINDS. IN THE
SHORTER TERM...A TROUGH OF LOW PRESSURE OVER CENTRAL AND EASTERN
LAKE SUPERIOR WILL EXIT ACROSS LAKE HURON THIS EVENING. THIS WILL
MAKE WAY FOR LARGE HIGH PRESSURE OVER CENTRAL CANADA AND THE
NORTHERN PLAINS TO SHIFT DIRECTLY OVER THE UPPER GREAT LAKES
WEDNESDAY AFTERNOON...WHERE IT WILL REMAIN THROUGH FRIDAY. A LOW
DEVELOPING OVER MANITOBA AND NORTH DAKOTA SATURDAY MORNING WILL
SLIDE OVER NORTHERN LAKE SUPERIOR AND ONTARIO SATURDAY NIGHT INTO
SUNDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLA
SHORT TERM...JLA
LONG TERM...KF
AVIATION...JLA
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
534 AM EDT TUE APR 3 2012
.SYNOPSIS...
ISSUED AT 533 AM EDT TUE APR 3 2012
RIDGE OVER THE AREA SINCE LATE IN THE WEEKEND IS BEING FLATTENED
OUT THIS MORNING AS STRONG SHORTWAVE TROUGH SLIDES FM MANITOBA INTO
NORTHWEST ONTARIO. HEIGHT FALLS ARE SUBTLE OVR UPR LAKES PER 00Z
RAOBS BUT ENOUGH TO TRIGGER MULTIPLE CLUSTERS OF SHRA/TSRA OVR THE
UPPER GREAT LAKES. FRONTAL BOUNDARY...EXTENDING SOUTH OUT OF LOW OVR
NORTHERN ONTARIO AND ALSO EXTENDING TO THE NORTH FM LOW OVR MID
MISSISSIPI RIVER VALLEY WILL CROSS UPR MICHIGAN THIS MORNING. COOLER
AIRMASS ADVECTS OVR THE AREA LATER TODAY THROUGH TONIGHT AND
WEDNESDAY. AFTER THE FROPA THIS MORNING...DRY WEATHER WILL PREVAIL
THROUGH LATE THIS WEEK AS LARGE HIGH PRESSURE IS DOMINANT WEATHER
FEATURE.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 533 AM EDT TUE APR 3 2012
TODAY...CONVECTIVE TRENDS WILL BE CHALLENGING THIS MORNING...BUT
AFTER THAT DRYING TREND WILL FIRMLY TAKE HOLD. AS OCCURRED 24 HR
AGO...MAIN AREA OF CONVECTION OVERNIGHT HAS DEVELOPED CLOSER TO H7
MOIST AXIS AND ALSO IN AREA OF H85 TEMP ADVECTION. INITIAL SHRA/TSRA
HEADING QUICKLY INTO THE FAR EAST CWA FORMED AHEAD OF ONTARIO
SHORTWAVE TROUGH AND HAVE BEHAVED FOLLOWING STEADY EASTWARD MOTION.
CONVECTION OVR MN AND WESTERN WI IS OUTLINED WELL BY WHERE RUC13
SHOWS MAXIMUM H7 MOISTURE TRANSPORT AND ON NORTHERN EDGE OF STEEPER
H7-H5 LAPSE RATES AOA 8C/KM. AT THIS TIME...MAJORITY OF TSRA ARE
OCCURRING OVR CNTRL WI BUT ADDITIONAL SHRA WITH EMBEDDED TSRA ARE
FILLING IN INTO NORTHWEST WI. FOLLOWING RUC IDEA THERE IS ENOUGH H7
MOISTURE TRANSPORT INTO SCNTRL CWA TO KEEP HIGHER POPS THERE IN THE
MORNING. A FEW SHRA/TSRA MAY EVEN CLIP AREAS FARTHER NORTH IN THE
CNTRL CWA BUT IT IS FAIRLY LIMITED CHANCE AS THE AREA OF SHRA/TSRA
OVR NORTHWEST WI WILL BE OUTRUNNING BETTER H7 MOISTURE CONVERGENCE
AND ELEVATED INSTABILITY IF THEY CONTINUE ON ENE TRACK. OVERALL
IMAGINE CHANCES OF CONVECTION WILL BEGIN TO WANE SIGNIFICANTLY OVR
MOST AREAS AFTER MID MORNING /POST 15Z-16Z/ SINCE SFC FRONT WILL BE
DROPPING S/SE OF THE AREA BY THAT TIME. HAVE HAD SOME PEA-SIZED HAIL
OVERNIGHT WITH STRONGER STORMS AND THAT REMAINS POSSIBLE THIS
MORNING GIVEN STEEP LAPSE RATES JUST UPSTREAM AND 30-35 KTS OF
EFFECTIVE SHEAR FCST OVR CNTRL PORTIONS OF UPR MI.
AS ALLUDED TO BEFORE...COLD FRONT WILL STEADILY SLIDE ACROSS THE
AREA MID TO LATE MORNING. WINDS IN WAKE OF FRONT EXPECTED TO BECOME
NORTH TO NORTHWEST. STILL APPEARS THAT THERE COULD BE BRIEF PERIOD
OF LOWER CIGS AND MAYBE SOME FOG AS HIGHER DWPNTS JUST BEHIND FRONT
SETTLE ACROSS LK SUPERIOR AND WINDS PROVIDE SOME UPSLOPE LIFTING OVR
HIGHER TERRAIN OF WESTERN AND NORTH CENTRAL CWA. POSSIBILITY FOR FOG
MAY HAVE BEEN ENHANCED DUE TO THE DECENT COVERAGE OF SHRA/TSRA OVR
LK SUPERIOR OVERNIGHT THAT MAY HAVE PROVIDED ADDITIONAL LOW-LEVEL
MOISTENING. LOOKING UPSTREAM THERE IS AREA OF LOWER CLOUDS NORTHWEST
OF LK SUPERIOR BUT THERE IS ALSO A MUCH LARGER AREA OF VERY DRY
AIR/CLEAR SKIES PUSHING ACROSS MANITOBA AND NORTHWEST ONTARIO.
REALLY HARD TO TELL AT THIS POINT HOW MUCH/IF ANY FOG IS PRESENT OVR
WESTERN LK SUPERIOR...SO WILL NOT INCLUDE IN FCST FOR LATER THIS
MORNING. EXPECT DRYING TO WIN OUT PRETTY EASILY AFTER MID AFTN ONCE
BLYR DWPNTS FALL INTO THE LOWER 30S/MID-UPR 20S AS HIGH BEGINS TO
NOSE INTO LK SUPERIOR REGION. SO SKY FCST SHAKES OUT AS FAIRLY
CLOUDY IN THE MORNING BUT WITH FAIRLY SHARP CLEARING TREND BY MID
AFTN FM WEST-TO-EAST. DESPITE THE SUNSHINE THIS AFTN...TEMPS SHOULD
BE HELD DOWN MOST AREAS WITH GRADIENT WIND FLOWING OFF LK SUPERIOR.
PROBABLY WILL SEE STEADY TEMPS ALONG LK SUPERIOR AND READINGS
PUSHING INTO LOWER 50S FAR INLAND/LK MICHIGAN SHORE WITH LESS LAKE
MODIFICATION GIVEN THE NORTHWEST WINDS. DWPNTS AND RH VALUES COULD
CRASH OVR INTERIOR WEST BY LATE AFTN. CURRENT FCST HAS RH VALUES IN
THE 30-40 PCT RANGE...BUT IF WINDS STAY MORE NW IT COULD GET WARMER
WHICH WOULD RESULT IN RH VALUES BLO 30 PCT.
VERY DRY AIRMASS BECOMES FIRMLY ENTRENCHED OVR AREA TONIGHT INTO
WEDNESDAY AS HIGH PRESSURE BUILDS FM HUDSON BAY INTO THE WESTERN
GREAT LAKES. NORTHERLY FLOW REMAINS OFF LK SUPERIOR BUT GIVEN PWATS
FALLING TOWARD 50 PCT OF NORMAL...EXPECT INTERIOR CWA TO TRY TO
DECOUPLE TONIGHT AND COOL OFF TOWARD THE LOWER DWPNTS ADVECTING INTO
THE REGION. BENEATH MOSTLY SUNNY SKIES ON WEDNESDAY...MAIN CONCERN
WILL BE ON FIRE WX WITH LOWER RH VALUES. HAVE DWPNTS IN AFTN MIXING
OUT INTO THE UPR TEENS OVR INTERIOR SECTIONS...RESULTING IN RH
VALUES BLO 30 PCT. WINDS WILL NOT BE VERY GUSTY /LEADING TO LESS
IMPACT ON FIRE WX CUSTOMERS/ BUT A STEADY NORTH WIND UP TO 15 MPH IS
EXPECTED. GIVEN THE FLOW...PROBABLY WILL HAVE TOUGH TIME REACHING 40
DEGREES ALONG LK SUPERIOR SHORE. MIXING HEIGHTS MUCH HIGHER TOWARD
WI BORDER /H85-H8 PER FCST SOUNDINGS/ ALLOW TEMPS TO RISE WELL INTO
THE 50S. OVERALL LOOKS LIKE PRETTY TYPICAL SPRING PATTERN.
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 533 AM EDT TUE APR 3 2012
HIGH PRESSURE WILL DOMINATE MUCH OF THIS PERIOD. WHILE THE SFC RIDGE
WILL BE OVERHEAD AT 00Z THURSDAY...THE MAIN HIGH WILL LIKELY RESIDE
OVER HUDSON BAY AND NW ONTARIO. EXPECT THE CENTER OF HIGH PRESSURE
TO SLOWLY SIDE OVER LAKE SUPERIOR THURSDAY INTO FRIDAY. DRY AIR WILL
CONTINUE TO SLIDE INTO THE AREA FROM EASTERN ONTARIO...WITH HUMIDITY
VALUES FALLING 25 TO 25 PERCENT THURSDAY AND FRIDAY AFTERNOON AWAY
FROM THE LAKE SUPERIOR COASTLINE. ON THE PLUS SIDE...WINDS SHOULD BE
FAIRLY LIGHT...LESS THAN 10KTS AWAY FROM ANY LAKE BREEZES THAT MAY
COME IN THURSDAY AND FRIDAY AFTERNOON. STILL...IT WILL BE ENOUGH TO
INCREASE FIRE WEATHER CONCERNS OVER UPPER MICHIGAN THROUGH THE
REMAINDER OF THE WORK WEEK.
THERE WILL BE A SUBTLE CHANGE FRIDAY...AS THE HIGH PRESSURE SYSTEM
BEGINS TO SHIFT EASTWARD IN RESPONSE TO A SFC LOW ORGANIZING OVER
EASTERN WY/MT INTO THE WESTERN DAKOTAS. LOOK FOR A SLOW RETURN TO
S/SE WINDS FRIDAY INTO FRIDAY NIGHT.
THE PRESSURE GRADIENT WILL TIGHTEN OVER THE WEEKEND. EXPECT
INCREASED S/SE WINDS OF 10 TO 15KTS SATURDAY /AHEAD OF THE COLD
FRONT CROSSING SATURDAY NIGHT/. SPECIFICS FOR THIS PERIOD ARE A
LITTLE TRICKY...WITH THE BREAKDOWN OF THE 500MB RIDGE SATURDAY NIGHT
AS THE MAIN LOW REMAINS WELL TO OUR NORTH. THE 03/00Z RUN OF THE
ECMWF CONTINUES TO SHOW LIMITED MOISTURE...WITH LITTLE MORE THAN A
TRACE OF RAIN FALLING SATURDAY NIGHT AS MUCH OF THE ENERGY REMAINS
WRAPPED UP ACROSS CANADA MAINLY ON THE BACK SIDE OF THE LOW. THE
03/00Z RUN OF THE GFS ON THE OTHER HAND INDICATES THE POTENTIAL FOR
AROUND A TENTH OF AN INCH OF WELL NEEDED RAIN...WITH STILL THE BEST
CHANCE BEHIND THE LOW. GIVEN THE LOW POTENTIAL FOR EVEN RAIN...KEPT
ONLY SLIGHT CHANCE TS IN THE FCST FOR SATURDAY AFTERNOON INTO
SATURDAY NIGHT.
WINDS WILL REMAIN STRONGER ON THE ORDER OF 15 TO 20KTS OUT OF THE W
BEHIND THE COLD FRONT AS THE SFC LOW SHIFTS FROM NEAR LAKE WINNIPEG
AT 12Z SATURDAY...TO NORTHERN ONTARIO/HUDSON BAY ON SUNDAY. NO
SIGNIFICANT WARM UP IS IN SIGHT...WITH 850MB TEMPS HOVERING AROUND
0C SUNDAY WITH TEMPS FALLING TO AROUND -8C MONDAY AFTERNOON ON N-NW
WINDS OFF LAKE SUPERIOR. DID NOT GO WITH FALLING SFC TEMPS FOR
MONDAY QUITE YET...EVEN THOUGH BOTH THE GFS AND ECMWF LOOK FAIRLY
CONSISTENT WITH THIS IDEA. AS NOTED IN THE PREVIOUS
DISCUSSION...WRAP AROUND MOISTURE LOOKS TO BET BEHIND THE
LOW...PARTICULARLY IN NW FLOW OFF LAKE SUPERIOR CAN LINGER OVER THE
CWA.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 155 AM EDT TUE APR 3 2012
FORCING AHEAD OF FRONTAL BOUNDARY /CURRENTLY OVER WESTERN LAKE
SUPERIOR/ HAS PROMPTED SOME CONVECTIVE SHOWERS AND THUNDERSTORMS
WHICH ARE CURRENTLY MOVING FROM WEST TO EAST ACROSS UPPER MI AND ALSO
DEVELOPING UPSTREAM OVER PORTIONS OF MN AND WESTERN WI. HAVE MENTION
OF VCTS AND CB FOR ALL TAF SITES TO ACCOUNT FOR THE SHOWER ACTIVITY
THROUGH LATE TONIGHT INTO TUESDAY MORNING. ONCE FRONTAL BOUNDARY
PASSES THROUGH TAF SITES EXPECT WINDS TO SHIFT TO A MORE NORTHERLY
DIRECTION AND FOR CIGS TO DROP TO MVFR AT ALL TAF SITES...THOUGH
MODELS ARE SHOWING HIGH LEVELS OF DISAGREEMENT ON TIMING OF THIS
SHIFT. THERE IS A CONCERN FOR FOG AT KCMX AND KSAW ONCE WINDS
SHIFT...SINCE COOL MOISTENED LAKE LAYER WILL BE ADVECTED ON TO THE
LAND WITH A NNW FLOW. MODELS ARE NOT SHOWING THIS...AND CONFIDENCE
IS LOW...SO HAVE LEFT OUT OF TAFS AT THIS TIME BUT WILL CONTINUE TO
MONITOR. HIGH PRESSURE TO WEST WILL ALLOW DRY AIR AND CLEARING SKIES
TO START WORKING IN FROM WEST TO EAST BY LATER TUESDAY AFTERNOON.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 533 AM EDT TUE APR 3 2012
WINDS SHOULD REMAIN LESS THAN 30KTS THROUGH THE PERIOD...GETTING
NEAR THIS LEVEL W AND CENTRAL SUNDAY AFTERNOON OFF WSW WINDS. IN THE
SHORTER TERM...A TROUGH OF LOW PRESSURE OVER CENTRAL AND EASTERN
LAKE SUPERIOR WILL EXIT ACROSS LAKE HURON THIS EVENING. THIS WILL
MAKE WAY FOR LARGE HIGH PRESSURE OVER CENTRAL CANADA AND THE
NORTHERN PLAINS TO SHIFT DIRECTLY OVER THE UPPER GREAT LAKES
WEDNESDAY AFTERNOON...WHERE IT WILL REMAIN THROUGH FRIDAY. A LOW
DEVELOPING OVER MANITOBA AND NORTH DAKOTA SATURDAY MORNING WILL
SLIDE OVER NORTHERN LAKE SUPERIOR AND ONTARIO SATURDAY NIGHT INTO
SUNDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLA
SHORT TERM...JLA
LONG TERM...KF
AVIATION...JMW/JLA
MARINE...KF
AREA FORECAST DISCUSSION
NWS GAYLORD MI
316 AM EDT TUE APR 3 2012
.SYNOPSIS...
A WEAK COLD FRONT WILL CROSS NORTHERN MICHIGAN THIS MORNING AND
EARLY IN THE AFTERNOON. RAIN CHANCES WILL END BY THIS EVENING.
AFTER THAT...HIGH PRESSURE WILL MOVE SOUTH OUT OF CENTRAL CANADA.
THIS WILL PROVIDE QUIET WEATHER...WITH A SERIES OF CHILLY NIGHTS BUT
RELATIVELY MILD DAYS. OUR NEXT CHANCE FOR RAIN WILL WAIT UNTIL
SATURDAY NIGHT AND SUNDAY.
&&
.SHORT TERM...(TODAY THROUGH WEDNESDAY)
ISSUED AT 313 AM EDT TUE APR 3 2012
QUITE AN AMPLIFIED PATTERN ONGOING OVER THE WESTERN HEMISPHERE EARLY
THIS MORNING...WITH LARGE SCALE TROUGHS ANCHORED ALONG BOTH COASTS
OF NOAM WITH A REX BLOCK-LIKE FEATURE STUCK BETWEEN
THESE...KEEPING THE WEATHER SOMEWHAT INTERESTING OVER WHAT WOULD
OTHERWISE BE LARGE-SCALE RIDGING.
THE FOCUS FOR THE NEAR TERM AND THROUGH TODAY IS SHOWER AND
THUNDERSTORM POTENTIAL AS INVERTED TROUGH PULLS INTO THE REGION FROM
THE WEST. OVERNIGHT...SHOWERS AND THUNDERSTORMS HAVE MADE THE MOST
OF VERY MEAGER INSTABILITY...CONTINUOUSLY FIRING ALONG THE H85
MOISTURE BOUNDARY AS IT PUSHES EAST INTO THE REGION. THROUGH
DAYBREAK...I EXPECT AREAS FROM M-32 NORTH TO SEE SOME SHRA ACTIVITY
/WITH A FEW EMBEDDED RUMBLES/...WITH A FEW MORE SHOWERS DOWN NEAR
MANISTEE.
THINGS GET TRICKIER AS WE HEAD INTO THE DAY TODAY...WITH THE IMPACTS
OF ANOTHER CONVECTIVE COMPLEX NOW OVER WESTERN WISCONSIN NOT SO
CERTAIN. CORFIDI VECTORS SUGGEST THAT THIS COMPLEX WILL PUSH EAST
AND THEN SOUTHEAST...OVER THE TOP OF THE H5 RIDGE AXIS...WHICH WOULD
SUGGEST ARRIVAL NEAR MY SOUTHWEST ZONES TOWARDS 12Z. THE HRRR IS ON
BOARD WITH THIS...AS IS OUR PREVIOUS GRIDDED FORECAST AND WILL
CONTINUE EARLY MORNING LIKELY POPS BASICALLY SOUTH OF M-72 AND WEST
OF INTERSTATE 75. GIVEN THE TIME OF DAY...EXPECT THIS COMPLEX TO
DIE AS IT MOVES EAST...WITH LITTLE TO HANG YOUR HAT ON FOR FORCING
FOR THE REMAINDER OF THE DAY AS AFOREMENTIONED INVERTED TROUGH
INCREASES LOW LEVEL CONVERGENCE TO SOME EXTENT. STILL...WITH MOIST
PLUME OVERHEAD...AND CVA FROM WAVE NOW MOVING INTO WESTERN
ONTARIO...EXPECT SOME ADDITIONAL SHOWERS TO POP UP ALONG THE H85
COLD FRONT AS IT SAGS THROUGH THE REGION THIS AFTERNOON. CONFIDENCE
IS PRETTY LOW IN HOW THIS EVOLVES THIS AFTERNOON...AND THAT IS WHY
I/LL KEEP POPS IN THE CHANCE CATEGORY. TEMPERATURES LIKELY WON/T
MAKE TOO MUCH PROGRESS GIVEN CLOUD COVER. REALLY LIKED INHERITED
HIGHS IN THE LOWER 50S /WITH A FEW MID 50S OVER SOUTHERN AREAS/ AND
WILL CONTINUE THEM IN THIS PACKAGE. THIS IS TOWARDS THE COOLER END
OF THE GUIDANCE ENVELOPE.
TONIGHT...DRIER AIR PUSHES INTO THE REGION AS INVERTED TROUGH SCOOTS
TO THE SOUTHEAST OF THE AREA WITH DEEP LAYER NORTHWEST FLOW
DEVELOPING. THIS SHOULD SCOUR OUT ANY REMNANT LOW LEVEL
MOISTURE...BRINGING CLEARING SKIES. WITH WINDS LIKELY TO REMAIN
COUPLED...I DON/T EXPECT LOWS TO FALL ALL THAT FAR...WITH FAIRLY
HOMOGENEOUS VALUES NEAR OR A LITTLE ABOVE 30 EXPECTED.
WEDNESDAY...EXPANSIVE AREA OF HIGH PRESSURE BUILDS SOUTH INTO THE
HUDSON BAY REGION WITH DRY NORTHWESTERLY FLOW VEERING NORTHERLY
DURING THE DAY UNDER CONTINUED COLD ADVECTION. GIVEN VERY DRY
ARRIVING AIRMASS...EXPECT A SUNNY/MSUNNY DAY WITH AMPLE SUBSIDENCE
TO ENSURE LITTLE IN THE WAY OF CUMULUS DEVELOPMENT. WITH THE
AFOREMENTIONED SUBSIDENCE...WOULDN/T BE SURPRISED IF WE DON/T MIX
QUITE AS HIGH AS THE MODELS ARE ADVERTISING...AND UNDER COLD
ADVECTION FEEL TEMPS WILL STRUGGLE A LITTLE. THEREFORE...WILL
FOLLOW CLOSER TO THE COOLER SIDE OF THE GUIDANCE ENVELOPE /MET/ WITH
HIGHS IN THE MID 40S OVER EASTERN UPPER...TO THE LOWER 50S OVER
NORTHERN LOWER. GIVEN THE FLOW TRAJECTORIES AND SUBSIDENT
FLOW...EXPECT A VERY DRY AIRMASS WITH DEWPOINTS LIKELY TUMBLING INTO
THE UPPER TEENS BY MID/LATE AFTERNOON. THIS WILL BRING MINIMUM RH/S
INTO THE 20S. WITH GUSTY NORTH/NORTHWEST WINDS...WILL CONTINUE
ELEVATED FIRE DANGER WORDING IN THE MORNING HWO...BUT TEMPERATURES
WILL BE WELL BELOW RED FLAG LEVELS.
&&
.LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY)
ISSUED AT 313 AM EDT TUE APR 3 2012
UPPER PATTERN REMAINS ONLY VERY SLOWLY PROGRESSIVE THRU THE REST OF
THE WORK WEEK AND INTO THE WEEKEND. THAT WILL STILL EVENTUALLY BRING
THE PAC NW UPPER TROF EASTWARD INTO OUR REGION...BUT LIKELY NOT
UNTIL THE END OF THE WEEKEND. BEFORE THEN...THURSDAY/FRIDAY/SATURDAY
CONTINUE TO LOOK RELATIVELY UNEVENTFUL...WITH SURFACE HIGH PRESSURE
ENTRENCHED IN THE GREAT LAKES REGION.
WED NIGHT-SAT...A REASONABLY VIGOROUS SHORTWAVE DROPS SOUTH ACROSS
THE NORTHERN LAKES WED NIGHT. THIS SYSTEM IS MOISTURE-STARVED...AND
WILL BRING NO MORE THAN SOME MID-HIGH CLOUDS...PRIMARILY TO EASTERN
UPPER AND NE LOWER MI. HOWEVER...IT WILL PUSH A SECONDARY COLD FRONT
ACROSS THE AREA...HELPING TO MAINTAIN 850MB TEMPS IN THE -6 TO -8C
RANGE BY THU MORNING. WARM ADVECTION (ON N TO NE LOW LEVEL FLOW) AND
AIRMASS MODIFICATION BEGIN SHORTLY THEREAFTER. BUT WE WILL STILL SEE
SOMEWHAT COOLISH TEMPS...ESPECIALLY WED NIGHT AND THU NIGHT. EXPECT
MINS MAINLY IN THE 20S...AND COULD DEFINITELY SEE TEENS IN THE USUAL
COLD INTERIOR LOCALES. GIVEN OUR EARLY START TO THE GROWING
SEASON...FROST/FREEZE HEADLINES COULD WELL BE NEEDED ON BOTH NIGHTS.
WE/LL SEE ENOUGH SUN TO KEEP MAX TEMPS RESPECTABLE THURSDAY...MID
40S TO AROUND 50. RH LEVELS WILL BE PRETTY LOW DESPITE THE COOLISH
TEMPS...WITH DEW POINTS IN THE TEENS (PERHAPS LOWER) AT PEAK HEATING.
FOR NOW...IT LOOKS LIKE WE WON/T QUITE HAVE ENOUGH OF A NORTHERLY
BREEZE TO MAKE FOR AN ENHANCED FIRE THREAT DAY.
HIGH PRESSURE MOVES OVERHEAD BY FRIDAY...AND THE AIRMASS WILL
CONTINUE TO MODERATE. MAX TEMPS WILL JUMP INTO THE 50S FRIDAY...AND
WILL APPROACH 60F IN SPOTS SATURDAY...WITH PLENTY OF SUNSHINE. AFTER
A DAY WITH HARDLY ANY WIND FRIDAY...A DEVELOPING SOUTHERLY BREEZE
SATURDAY COULD ALSO PRODUCE AN ENHANCED FIRE THREAT...THOUGH FOR NOW
(LIKE THURSDAY) FORECAST WINDS AREN/T QUITE STRONG ENOUGH.
LATER PERIODS...TIMING AGREEMENT REMAINS DECENT ON LOW PRESSURE
LIFTING TOWARD HUDSON BAY SAT NIGHT/SUNDAY...AND AN ASSOCIATED COLD
FRONT CROSSING MI LATE SAT NIGHT/SUNDAY MORNING. CHANCE POPS STILL
IN ORDER WAY OUT THEN. DEPENDING ON YOUR MODEL SOLUTION OF CHOICE...
MAY HAVE ENOUGH COOL AIR AND DEEP CYCLONIC FLOW TO PRODUCE A CHANCE
FOR RAIN/SNOW SHOWERS ON MONDAY. THE OPERATIONAL GFS IS AMONGST
THE CHILLIEST/MOST MOIST BY MONDAY...IT HAS BEEN KNOWN TO OVERDUE
THESE SORTS OF THINGS FROM TIME TO TIME.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 138 AM EDT TUE APR 3 2012
A TROUGH OF LOW PRESSURE IS BEGINNING TO PULL INTO THE REGION AS
OF THIS WRITING...WITH A BAND OF SHOWERS OVER EASTERN UPPER
MICHIGAN...AND ADDITIONAL ACTIVITY FIRING FURTHER WEST BACK
OVER WESTERN WISCONSIN. EXPECT GRADUALLY LOWERING MID/HIGH CLOUDS
THROUGH THE REMAINDER OF THE OVERNIGHT HOURS...WITH A SHRA
POSSIBLE BEFORE DAYBREAK AT PLN/TVC/MBL. OTHERWISE...EXPECT
STEADIER PRECIPITATION TO REACH MBL/TVC AROUND DAYBREAK /MISSING
APN AND PLN TO THE SOUTH/ AND LAST THROUGH THE MORNING /PROVIDING
SOME MVFR VSBYS/ WITH A FEW EMBEDDED THUNDERSTORMS POSSIBLE. AFTER
THIS PUSHES THROUGH...EXPECT WE/LL SEE SOME MVFR CIGS DEVELOP
BEFORE MUCH DRIER AIR ARRIVES TOWARDS THIS EVENING...CLEARING
THINGS OUT.
LLWS A THREAT THROUGH DAYBREAK AS 1.5KFT WINDS ARE NEAR 30KTS AT
MBL/TVC/PLN BASED ON VWP ANALYSIS ALONG WITH NEAR TERM MODEL
FORECAST SOUNDINGS. THIS THREAT SHOULD DIMINISH AFTER SUNRISE.
LIGHT WINDS WILL BECOME SOUTHERLY AROUND 5KTS FOR THE MORNING
BEFORE SHIFTING NORTHWEST AND INCREASING TO 8G14KTS FOR THE
AFTERNOON. NORTHWEST WINDS 5-10KTS /EXCEPT NORTHEAST AT MBL/ ARE
EXPECTED AS WE HEAD INTO THIS EVENING.
&&
.MARINE...
ISSUED AT 313 AM EDT TUE APR 3 2012
WINDS/WAVES LOOK TO GENERALLY REMAIN BELOW LEVELS HAZARDOUS TO SMALL
CRAFT THROUGH TUESDAY NIGHT AS TROUGH OF LOW PRESSURE MOVES THROUGH
THE REGION TODAY WITH NORTHWESTERLY WINDS DEVELOPING LATE THIS
AFTERNOON AND TONIGHT. THESE NORTHWESTERLY WINDS WILL STRENGTHEN ON
WEDNESDAY AS CANADIAN HIGH PRESSURE BUILDS TOWARDS THE REGION. THIS
WILL LIKELY BRING A PERIOD OF SMALL CRAFT CONDITIONS ON WEDNESDAY
BEFORE THE AFORMENTIONED HIGH SETTLES OVERHEAD WITH QUIET CONDITIONS
FOR THE END OF THE WEEK.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&
$$
UPDATE...JA
SYNOPSIS...JZ
SHORT TERM...JA
LONG TERM....JZ
AVIATION...JA
MARINE...JA
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON MS
943 PM CDT WED APR 4 2012
.UPDATE...EVENING ANALYSIS SHOWED PLENTY OF DRY AIR HAD FOLLOWED THE
WEDNESDAY MORNING MCS INTO MUCH OF OUR CWFA. PWATS HAD DROPPED TO
JUST UNDER 1 INCH AT 00Z WITH VIRTUALLY NO LOW LEVEL CONVERGENCE
NOTED IN THE IMMEDIATE AREA TO FOCUS ANY ADDITIONAL TSRA. HOWEVER LL
MOISTURE RETURN HAD ALSO DEVELOPED UP THE SABINE RIVER VALLEY TO OUR
W AND MID LEVEL 7-500MB LAPSE RATES REMAIN QUITE IMPRESSIVE AT NEARLY
8C ALONG THE MS RIVER. A FIRST BATCH OF ELEVATED SHRA OVER NRN AND
CENTRAL LA WAS STRUGGLING TO DEVELOP SINCE 22Z AND HAVE BUMPED ALL
POPS DOWNWARD THRU MIDNIGHT.
THE MID LEVEL LOW SPINNING EWD ACROSS CENTRAL OK MOVES INTO NRN AR
OVERNIGHT AND THEN WRN TN THURSDAY MORNING. LATEST RUC13 SHOWS SOME
TSRA EVENTUALLY FORMING/DEVELOPING INTO SWRN/ SRN MS AFTER MIDNIGHT
WITH MORE INTENSE ACTIVITY STAYING S OF I-10. MEANWHILE...HRR/SREF
RUNS SHOW A SEPARATE AND MORE POTENT BAND OF TSRA FORMING ALONG A
KPBF-KMLU-KLFT AXIS ABOUT 09Z-12Z AND EXPANDING QUICKLY EWD INTO THE
WRN HALF OF CWFA THROUGH 15-18Z. THESE STORMS SHOULD REMAIN ELEVATED
BUT PACK A BIT OF PUNCH WITH QUARTER SIZED HAIL AND BRIEF WIND GUSTS
OF 50-60MPH BEING LIMITED BY WEAK LOW LEVEL WIND FIELDS/SHEAR.
HAVE GENERALLY BACKED OFF ON OVERNIGHT POPS FOR OUR ERN PORTIONS AND
THEN BOOSTED THEM IN THE MS PORTIONS THURSDAY MORNING AS A DISTINCT
VORT TROUGH SWINGS THE FINAL ROUND OF STORMS THROUGH THE CWFA. THESE
STORMS COULD INTENSIFY A BIT MORE AS THEY BECOME SURFACE BASED IN ERN
MS AROUND MIDDAY THURSDAY AND LAST INTO THE AFTERNOON HOURS./40/
&&
.AVIATION...VFR CONDITIONS PREVAILED ACROSS ALL SITES THROUGH EARLY
EVENING WITH ONLY CIRRUS LEVEL CLOUDS NOTED. EXPECT SOME BROKEN
CLOUD LAYERS 4-6K FEET DEVELOPING FROM W TO E THROUGH 06Z. MVFR
CONDITIONS DEVELOP 06Z-10Z TONIGHT...MAINLY SW OF HWY 49 AND SHOULD
BECOME AREAS OF IFR CONDITIONS IN CONVECTION AND LOW STRATUS THROUGH
16Z THU MORNING. CONDITIONS RETURN TO MOSTLY VFR AGAIN W OF I-55
18Z-20Z WHILE MVFR HOLDS FOR LOCATIONS TO THE E. A FEW STRONG TO
SEVERE STORMS WILL BE POSSIBLE EARLY THU ACROSS THE FAR WRN AREAS
GENERALLY ALONG AND WEST OF THE MS RIVER...THEN THE REST OF THE
REGION AFTER DAYBREAK./40/
&&
.PREV DISCUSSION... /ISSUED 344 PM CDT WED APR 4 2012/
DISCUSSION...LATE THIS AFTERNOON INTO THURSDAY...AS ELUDED TO
EARLIER THE EXPANSIVE AREA OF SHOWERS AND STORMS...NOW WELL OFFSHORE
OVER THE NORTH CENTRAL GULF OF MEXICO...THAT MOVED ACROSS THE
FORECAST AREA OVERNIGHT INTO THIS MORNING HELPED TO STABILIZE OUR
AIRMASS FOR TODAY THUS LIMITING CONVECTIVE DEVELOPMENT. THE CIRRUS
DEBRIS FROM SAID AREA REMAINS OVER A GOOD PORTION OF THE CWA BUT IS
ERODING FROM WEST TO EAST. AS THE ATMOSPHERE WARMS AND SLOWLY
DESTABILIZE LATE THIS AFTERNOON INTO THIS EVENING...ISOLATED SHOWERS
OR STORMS COULD POPPING UP ACROSS THE AREA.
MODELS CONTINUE TO SHOW THE AIRMASS OVER THE REGION GRADUALLY
RECOVERING LATE THIS AFTERNOON AND INTO TONIGHT AHEAD OF A COLD
FRONT CURRENTLY OVER EAST TEXAS AND A VIGOROUS UPPER LOW SPINNING
INTO WEST CENTRAL OKLAHOMA. WHILE LITTLE MOVEMENT IS OCCURRING WITH
THIS SYSTEM...AN UPPER LEVEL TROUGH DROPPING SOUTHEAST ACROSS THE
PACIFIC NORTHWEST THIS EVENING WILL CAUSE THIS FRONT AND UPPER LOW
TO SPEED ITS EASTWARD PROGRESSION UP A BIT... BRINGING IT CLOSER TO
THE ARKLAMISS REGION OVERNIGHT...AND EVENTUALLY THROUGH THE REGION
DURING THE COURSE OF THE DAY THURSDAY.
CURRENT THINKING IS THAT IF WE INDEED SEE ANY SEVERE WEATHER ACROSS
THE CWA...IT`LL BE FROM LATE TONIGHT INTO THURSDAY AS LOBES OF
ASCENT ROTATE AROUND THE BASE OF THE AFOREMENTIONED UPPER LOW AIDING
IN THE DEVELOPMENT OF CONVECTION. HIGH-RES AND EVEN SOME OF THE
GLOBAL MODELS AGREE WITH THIS. ONCE AGAIN THE HIGH-RES MODELS HAVE
DONE A GOOD JOB WITH THIS PATTERN/REGIME WE`RE CURRENTLY DEALING
WITH. BECAUSE OF THIS...I`M FINDING IT DIFFICULT TO STRAY TOO FAR
FROM THEIR ASSESSMENT.
WITH THE ATMOSPHERE AGAIN IN THE PROCESS OF RECOVERING AND BETTER
INSTABILITY IN PLACE...COUPLED WITH BETTER FORCING COMING IN FROM
THE WEST...CONTINUED STEEP MID-LEVEL LAPSE RATES...AND ADEQUATE WIND
SHEAR...SHOWERS AND STORMS SHOULD BEGIN TO INITIATE ACROSS NORTHERN
AND CENTRAL LOUISIANA THIS EVENING...AND PUSH EAST NORTHEAST INTO
THE FORECAST AREA LATER TONIGHT AND INTO THURSDAY. SOME MODELS ALSO
SUGGEST THAT ACTIVITY COULD CONGEAL INTO A COMPLEX AND RACE THROUGH
THE CWA OVERNIGHT INTO THURSDAY MORNING.
WITH ALL OF THAT SAID...WILL CONTINUE TO MENTION THE POTENTIAL FOR A
FEW STRONG TO SEVERE STORMS CAPABLE OF PRODUCING LARGE HAIL AND
DAMAGING WIND GUSTS...WITH EVEN A TORNADO OR TWO POSSIBLE...IN THE
HWO TONIGHT INTO THURSDAY. THE BEST POTENTIAL FOR SUCH CONVECTION
TONIGHT APPEARS TO BE SW OF THE HIGHWAY 49 CORRIDOR...AND THEN
SHIFTING TO THE EASTERN HALF OF THE CWA ON THURSDAY. THE POTENTIAL
FOR HEAVY RAINFALL PERHAPS RESULTING IN SOME LOCALIZE FLASH FLOODING
CANNOT BE RULED OUT EITHER...ESPECIALLY ACROSS MY SOUTHERN ZONES
WHERE A GENERAL 1-2 INCHES OF RAIN FELL AS A RESULT OF YESTERDAY AND
THIS MORNING`S ACTIVITY. WILL HOLD OFF ON ISSUING A FLASH FLOOD
WATCH THOUGH AS A GOOD BIT OF UNCERTAINTY REMAINS WITH HOW THINGS
WILL EXACTLY UNFOLD TONIGHT INTO TOMORROW. /19/
THURSDAY NIGHT THROUGH NEXT TUESDAY...GLOBAL MODELS ARE IN EXCELLENT
AGREEMENT THAT THE MID LEVEL RIDGE WILL REBUILD OVER THE ARKLAMISS
BRINGING A RETURN TO DRY CONDITIONS AND NEAR TO ABOVE NORMAL
TEMPERATURES AS WE GO INTO THE WEEKEND. MODELS HAVE BACKED OFF ON
THE INFLUENCE OF A NORTHERN STREAM TROUGH THAT WAS EXPECTED TO BRING
A RETURN TO SHOWER/TSTM CHANCES FROM SUNDAY INTO MONDAY...AND THIS
SEEMS REASONABLE GIVEN THE STRENGTH OF THE RIDGE IN PLACE. HAVE
FOLLOWED MEX MOS GUIDANCE AND LIMITED SMALL RAIN CHANCES TO
MONDAY/MON NIGHT FOR NOW.
OTHERWISE...IT STILL APPEARS THERE WILL BE A CHANGE IN THE PATTERN
FOR EARLY-MID NEXT WEEK WITH MODELS CONTINUING TO SHOW RETROGRESSION
OF THE MEAN RIDGE POSITION AND DEVELOPMENT OF A STRONG EASTERN CONUS
TROUGH. THIS WOULD INDUCE COOL NORTHWEST FLOW OVER THE ARKLAMISS AND
A PERIOD OF COOLER WEATHER AND BELOW NORMAL TEMPERATURES IF IT
VERIFIES. AT THIS TIME...IT DOES NOT LOOK COOL ENOUGH TO BRING A
LATE SEASON FROST/FREEZE. /EC/
&&
.PRELIMINARY POINT TEMPS/POPS...
JACKSON 60 80 54 76 / 40 50 6 4
MERIDIAN 62 82 52 77 / 34 52 11 4
VICKSBURG 57 80 54 77 / 53 33 4 4
HATTIESBURG 64 83 57 81 / 36 47 4 3
NATCHEZ 61 80 55 77 / 53 31 4 3
GREENVILLE 57 79 54 72 / 52 23 2 3
GREENWOOD 59 80 52 73 / 39 39 5 3
&&
.JAN WATCHES/WARNINGS/ADVISORIES...
MS...NONE.
LA...NONE.
AR...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1229 PM CDT TUE APR 3 2012
.AVIATION...18Z TAF. PRIMARY FORECAST CONCERN FOR THIS TAF PERIOD
LIES WITH WINDS/CLOUDS THIS AFTERNOON...THEN PRECIPITATION CHANCES
LATER TONIGHT AND INTO TOMORROW. MAIN DRIVER REMAINS THE UPPER
LEVEL LOW PRESSURE SYSTEM SPINNING OVER THE ERN CO/NM
BORDER...WITH CLOUDS CONTINUING TO STREAM NORTH INTO THE REGION.
EXPECTING MVFR CONDITIONS TO REMAIN THROUGH THE TAF PERIOD...WITH
LOWER VISIBILITIES COMING TOWARD THE END OF THE PERIOD WHEN
PRECIPITATION CHANCES INCREASE. KEPT THE 09Z START TIME FOR
SHOWERS...THOUGH IT MAY VARY A BIT...JUST DEPENDS ON THE MODEL.
OBVIOUSLY WILL GET A BETTER FEEL FOR TRENDS ONCE PRECIPITATION
STARTS MOVING INTO THE AREA. WITH THE MAIN SURFACE LOW REMAINING
OFF TO THE S/SW...WINDS ARE EXPECTED TO REMAIN N/NERLY THROUGH THE
TAF PERIOD. SPEEDS WILL REMAIN GUSTY THIS AFTERNOON BEFORE
DIMINISHING THIS EVENING/OVERNIGHT...BUT GUSTY CONDITIONS LOOK TO
RETURN TOWARD THE END OF THE PERIOD.
&&
PREV DISCUSSION... /ISSUED 355 AM CDT TUE APR 3 2012/
SHORT TERM...THROUGH THURSDAY NIGHT. PRIMARY CHALLENGE OVER THE
NEXT 72 HOURS IS CLEARLY RAINFALL TRENDS/AMOUNTS...AS THE MID
LEVEL LOW CURRENTLY CENTERED OVER EASTERN NEW MEXICO GRADUALLY
LUMBERS EASTWARD NEAR THE OK/KS BORDER...AND EVENTUALLY INTO THE
MID-SOUTH BY THURSDAY. CERTAINLY PARTS OF THE CWA ARE GOING TO SEE
SOME WELL-TIMED BENEFICIAL RAINS IN EXCESS OF 0.75-INCH. ALSO NOT
GOING TO SEE MUCH SUNSHINE FOR THE NEXT FEW DAYS.
STARTING OFF EARLY THIS MORNING...08Z OBJECTIVE SURFACE ANALYSIS
SHOWS THE CWA LOCATED WELL NORTH OF THE PRIMARY SURFACE COLD FRONT
STRETCHED NORTHEAST ACROSS SOUTHEAST KANSAS FROM A FAIRLY WEAK LOW
OVER THE TX PANHANDLE. WELL OFF TO THE NORTHWEST...A
BROAD...ROUGHLY 1025 MB HIGH PRESSURE SYSTEM IS CENTERED ACROSS
THE NORTHERN ROCKIES INTO ND. WITH THE CWA POSITIONED WITHIN THE
HEART OF THE MAIN NORTH-SOUTH SURFACE PRESSURE GRADIENT...STEADY
NORTH WINDS HAVE PREVAILED ALL NIGHT...WITH SUSTAINED SPEEDS
COMMONLY 20-30 MPH WITH HIGHER GUSTS...BUT GENERALLY FALLING SHORT
OF WIND ADVISORY CRITERIA IN MOST PLACES. RADAR...11-3.9 MICRON
SATELLITE IMAGERY AND AUTOMATED OBS DEPICT A CORRIDOR OF
WIDESPREAD SHOWERS AND EMBEDDED THUNDERSTORMS CENTERED OVER
CENTRAL/NORTHWEST KANSAS...WITH SOME OF THIS ACTIVITY STARTING TO
INCREASINGLY AFFECT AREAS MAINLY SOUTHWEST OF A BEAVER CITY-BELOIT
LINE. AS FOR RAINFALL AMOUNTS IN THE PAST 12 HOURS...RADAR
ESTIMATES THAT POCKETS OF THE SOUTHERN CWA...MAINLY THE KS
COUNTIES...HAVE LIKELY TALLIED BETWEEN 0.25-0.50 INCH...ALTHOUGH
MOST AREAS PROBABLY LESS. OTHERWISE...AN EXPANSIVE AREA OF LOW
STRATUS MAINLY IN THE 800-1800 FT RANGE HAS OVERTAKEN THE ENTIRE
CWA...WITH JUST A HINT OF LIGHT DRIZZLE IN THE AIR HERE AT THE
WFO. UP TOP...WATER VAPOR SATELLITE CLEARLY DEPICTS THE
AFOREMENTIONED CLOSED LOW CENTERED NEAR THE NM/TX BORDER...WHILE A
RATHER PRONOUNCED RIDGE DOMINATES MUCH OF THE EASTERN CONUS.
GETTING TO THE FORECAST AND STARTING WITH TODAY...IMMEDIATE SHORT
TERM ISSUE OVER THE NEXT 4-6 HOURS IS PROGRESSION OF NEXT BATCH OF
GENERALLY WEAK CONVECTION RIDING UP INTO SOUTHERN ZONES. WILL BE
ISSUING A PRE-FIRST PERIOD ZONE FORECAST PACKAGE...WITH LIKELY
POPS THROUGH 12Z FOR LOCATIONS MAINLY SOUTH OF A BEAVER CITY-
BELOIT LINE. WITH RUC ADVERTISING AT LEAST 500 J/KG MUCAPE IN
THESE AREAS...OCCASIONAL SMALL HAIL AND BRIEF BUT FREQUENT
LIGHTNING STRIKES CERTAINLY ARE POSSIBLE EARLY THIS MORNING.
OTHERWISE...FOLLOWING LATEST HRRR REFLECTIVITY PROGS...ALONG WITH
00Z 4KM WRF-NMM....MUCH OF THIS ACTIVITY SHOULD DECREASE IN
COVERAGE...AND FAIL TO PUSH VERY FAR INTO THE NEB CWA OVER THE
NEXT FEW HOURS AS THE SMALL SCALE SHORTWAVE CURRENTLY OVER
NORTHWEST KS ROTATES BACK MORE TO THE WEST-NORTHWEST.
MOVING ON TO THE DAYTIME 12Z-00Z TIME FRAME...ASSUMING THAT THE
CURRENT CONVECTION DISSIPATES OR MOVES OUT BY AROUND
SUNRISE...REALLY NOT EXPECTING A WHOLE LOT OF PRECIP POTENTIAL FOR
THE MAJORITY OF THE CWA...AS THE LOCAL AREA REMAINS IN A BIT OF A
LULL IN BETWEEN PUSHES OF MID/UPPER FORCING...WAITING FOR THE NEXT
PRIMARY CHUNK OF ENERGY TO ROTATE NORTHWARD OUT OF THE SOUTHERN
PLAINS AHEAD OF THE UPPER LOW. AS A RESULT...ACTUALLY HAVE NO
PRECIPITATION MENTIONED WHATSOEVER ACROSS ROUGHLY THE NORTHEAST
1/2 OF THE CWA THROUGH THE DAY...AND ONLY 20-50 PERCENT POPS
ACROSS SOUTHWEST ZONES...WITH EVEN THIS POTENTIALLY BEING TOO
MUCH. EVEN IN AREAS WITH NO EXPECTATION OF MEASURABLE
PRECIP...SUPPOSE SOME PATCHY DRIZZLE COULD CONTINUE PAST
SUNRISE...BUT WILL LEAVE IT OUT FOR NOW AND TAKE ANOTHER LOOK ON
UPDATE IN A FEW HOURS. IF ANY CONVECTION DOES SURVIVE/MOVE IN
DURING THE DAY...ISOLATED THUNDER POTENTIAL IS CERTAINLY THERE
WITH CONTINUED MUCAPE AVERAGING GENERALLY BELOW 500 J/KG...BUT
POSSIBLY COULD BE ENOUGH TO GENERATE SOME SMALL HAIL. AS FOR HIGH
TEMPS TODAY...FEEL THAT AT LEAST SLIGHTLY UNDERCUTTING MET/MAV
GUIDANCE CONSENSUS IS THE WAY TO GO...AS LOW CLOUDS AND STEADY
NORTHERLY BREEZES OF 15-25 MPH WILL PERSIST THROUGH THE DAY. MAY
STILL BE TOO WARM IN SPOTS...BUT FOR NOW WILL AIM FOR MID-UPPER
50S IN MOST WESTERN AREAS...AND MAYBE SOME LOW 60S IN THE EAST. IN
STARK CONTRAST TO THE PAST SEVERAL WEEKS...THESE HIGHS WOULD BE
VERY NEAR IF NOT SLIGHTLY BELOW NORMAL FOR A CHANGE.
THIS EVENING/TONIGHT...THIS IS WHEN LEGITIMATE WIDESPREAD RAINFALL
WILL RAMP UP...BUT MAINLY ACROSS THE SOUTHERN 1/2 OF THE CWA. IN
SHORT...UPPER DIVERGENCE INCREASES TO THE NORTH OF THE PARENT MID
LEVEL LOW...WHICH WILL BE CENTERED GENERALLY OVER THE OK
PANHANDLE. IN RESPONSE...A CLASSIC...GENERALLY EAST-WEST BAND OF
STEADY SHOWERS AND POSSIBLY SOME EMBEDDED WEAK THUNDERSTORMS WILL
GRADUALLY LIFT NORTH ACROSS KS THIS EVENING...AND HAVE POPS PRIOR
TO 06Z RANGING FROM ONLY 20 PERCENT NEAR KGRI...TO 90 PERCENT IN
MOST OF NORTH CENTRAL KS WHERE THE MAIN PRECIP AXIS WILL SET UP.
FOR THE LATE NIGHT PERIOD...THEN HAVE HIGH 70-90 POPS EXPANDING
NORTHWARD OUT OF KS INTO MUCH OF SOUTH CENTRAL NEB...BUT MAINLY
SOUTH OF I-80. GIVEN TRENDS OF LATEST 06Z NAM...ALONG WITH 4KM
WRF-NMM...AM STARTING TO WONDER IF NORTHERN COUNTIES SUCH AS
VALLEY/NANCE ETC. WILL SEE MUCH OF ANYTHING BEFORE SUNRISE WED
MORNING...AND A TIGHTER POP GRADIENT BETWEEN THE HAVES AND HAVE
NOTS MAY PROVE NECESSARY. AS FOR RAINFALL AMOUNTS...EXPECT AT
LEAST THE SOUTHERN 1/2 TO 1/3 OF THE CWA TO MEASURE BETWEEN
0.25-0.75 INCH OVERNIGHT...WITH LOCALLY HIGHER AMOUNTS
POSSIBLE...AND AGAIN...A FAIRLY SHARP CUTOFF LIKELY SOMEWHERE NEAR
I-80. ALTHOUGH CERTAINLY NOT EXPECTING SEVERE WEATHER...WILL KEEP
ISOLATED THUNDER MENTION OVERNIGHT MAINLY ACROSS THE SOUTHERN 1/3
OF THE CWA...BUT EVEN SMALL HAIL SHOULD BE HARD TO COME BY.
WEDNESDAY...FAIRLY WIDESPREAD RAIN SHOWERS WILL CONTINUE AS THE
PARENT MID LEVEL CIRCULATION TRAVERSES EASTWARD NEAR OR JUST SOUTH
OF THE KS/OK BORDER. KEPT A BROAD AREA OF LIKELY POPS GOING CWA-
WIDE THROUGH THE DAY...ALTHOUGH LATEST NAM/ECWMF CONTINUE TO
SUGGEST THAT THE NORTHERN 1/4 OR SO OF THE CWA...GENERALLY NORTH
OF HWY 92...COULD STRUGGLE TO SEE MUCH...AND POPS IN THESE AREAS
INCLUDING ORD/GREELEY MAY NEED TONED DOWN IN LATER FORECASTS. WITH
WIDESPREAD CLOUDS/ONGOING PRECIP...LOWERED HIGH TEMPS 2-4 DEGREES
IN MOST AREAS FROM PREVIOUS FORECAST...WITH ONLY LOW-MID 50S MOST
AREAS.
WEDNESDAY NIGHT...SHOWERS SHOULD GRADUALLY END FROM NORTHWEST-
SOUTHEAST AS THE PARENT LOW PROGRESSES TO NEAR THE OK/AR
BORDER...AND IT MAY VERY WELL END UP THAT MOST OF THE
CWA...ESPECIALLY THE NORTHWEST 1/2...COULD STAY HIGH AND DRY
THROUGH THE NIGHT. FOR NOW THOUGH WILL CONTINUE 20-40 POPS
CWA-WIDE.
THURSDAY...WILL CONTINUE TO KEEP IT DRY...RUNNING WITH THE
ASSUMPTION THAT THE DEPARTING SYSTEM SHOULD BE FAR ENOUGH
AWAY...ALTHOUGH SUPPOSE A FEW LIGHT WRAP AROUND SHOWERS COULD
FLIRT WITH PARTS OF THE KS CWA. WITH AT LEAST PARTIAL SUNSHINE
EXPECTED TO RETURN...TEMPS ARE FORECAST TO REBOUND BACK INTO THE
LOW-MID 60S FOR HIGHS...BUT AM STAYING JUST BELOW THE MET/MAV
GUIDANCE BLEND FOR NOW. AS SURFACE HIGH PRESSURE SLIDES EAST
EAST-SOUTHEAST WINDS WILL PICK UP A BIT AS THE DAY WEARS ON.
THURSDAY NIGHT...WILL ALSO MAINTAIN A DRY FORECAST...ALTHOUGH BOTH
THE NAM/GFS ARE DEPICTING CONSIDERABLE LOW LEVEL SATURATION AND
POSSIBLE DRIZZLE POTENTIAL MAINLY ACROSS WESTERN NEB/KS...BUT FOR
NOW MOST IF NOT ALL OF THIS POTENTIAL LOOKS TO REMAIN WEST OF THE
CWA THROUGH THE NIGHT.
ALTHOUGH NOT IN THE FORECAST GRIDS AT THIS TIME...SUPPOSE SOME
FOG REDUCING VISIBILITY AT LEAST INTO THE 1-2 MILE RANGE IS
POSSIBLE ACROSS PARTS OF THE AREA EACH OF THE NEXT 3 NIGHTS...BUT
WITH PRECIP GENERALLY EXPECTED TO BE FAIRLY WIDESPREAD AT LEAST
THE NEXT 2 NIGHTS...NOT LOOKING LIKE AN OBVIOUS SETUP FOR
WIDESPREAD...IMPACTFUL FOG.
IN CLOSING...THIS SYSTEM WILL UNDOUBTEDLY BE A BENEFICIAL
RAINER IN MANY AREAS...HELPING MAKE UP FOR A MARCH PRECIP DEFICIT.
HOWEVER...THERE WILL LIKELY BE A SHARP NORTH-SOUTH RANGE IN
RAINFALL AMOUNTS OVER THE NEXT 24-48 HOURS...WITH CURRENT FORECAST
GRIDS AIMING FOR TOTALS RANGING FROM AT LEAST 1 TO 1.5 INCHES FOR
MOST AREAS NEAR/SOUTH OF I-80...BUT ONLY 0.25-0.50 INCH...AND
MAYBE NOT EVEN THAT MUCH...FOR SOME NORTHERN COUNTIES.
LONG TERM...FRIDAY THROUGH MONDAY. BEGINNING ON FRIDAY AN UPPER
LOW IS FORECAST TO BE CENTERED IN THE PACIFIC NW WITH TROUGH AXIS
EXTENDING THRU THE CENTRAL ROCKIES. IN SOUTHWEST FLOW ALOFT ACROSS
THE CENTRAL PLAINS...SFC TROUGH DEEPENS ALONG THE HIGH PLAINS. AS
SFC GRADIENT TIGHTENS SOUTHERLY WINDS WILL INCREASE WITH BREEZY
CONDITIONS SETTING UP BY AFTN AND MOISTURE WILL WORK NORTHWARD WITH
DPS RISING DURING THE AFTN. ALTHOUGH MAIN FORCING WILL ARRIVE
FRIDAY NIGHT AS UPPER SYSTEM LIFTS ACROSS THE NORTHERN PLAINS AND
ASSOCIATED COLD FRONT CROSS OUR REGION...MODELS DO INDICATE SOME
THETA E ADVECTION FRIDAY AHEAD OF SYSTEM AND WILL MAINTAIN OUR
CURRENT LOW POPS DURING THE DAY FRIDAY. AS FRONT CROSSES FRIDAY
NIGHT THERE IS A NARROW AXIS OF INSTABILITY ALONG/AHEAD OF
BOUNDARY...MUCAPES NEARING 1000 J/KG...AND COULD POTENTIALLY SEE A
STRONG STORM OR TWO.
EASTER WEEKEND IS SHAPING UP TO BE DRY AND SEASONAL OVERALL. A
1030MB SURFACE HIGH BUILDS SOUTH BEING THE FRONT AND SETTLES ACROSS
THE CENTRAL PLAINS OVERNIGHT. SFC DPS ARE PROGGED TO DROP TO THE
TEENS IN OUR NW WITH 20S IN THE SOUTHEAST IN THE DRY AIRMASS.
LOOKING LIKE A MUCH COLDER NIGHT THAN WE HAVE HAD RECENTLY HOWEVER
NOT NECESSARILY UNUSUAL FOR THIS TIME OF YEAR WITH NORMAL LOWS IN
THE LOW/MID 30S. FORECAST LOWS ARE IN THE 30S IN GENERAL AND AGREE
PREVIOUS SHIFTS THAT THIS PERIOD WILL NEED TO BE MONITORED FOR
FROST/FREEZE POTENTIAL.
SURFACE RIDGE AXIS SLIPS SOUTHEAST ON SUNDAY WITH RETURN FLOW
SETTING UP DURING THE DAY. ANOTHER COLD FRONT CROSSES THE PLAINS
SUNDAY NIGHT/MONDAY ASSOCIATED WITH UPPER LOW IN ONTARIO AND TROUGH
EXTENDING ACROSS THE UPPER MIDWEST/OHIO VALLEY REGION. BRUNT OF
COLD AIR REMAINS EAST OF THE MISSOURI RIVER...HOWEVER SOME COOLER
AIR DOES BACK INTO OUR NORTHEAST COUNTIES. THIS BEING
SAID...ALTHOUGH HIGHS MAY DROP A DEGREE OR TWO FROM SUNDAY...TEMPS
OVERALL ARE STILL LOOKING SEASONAL OR SLIGHTLY ABOVE.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
AVIATION...ADO
SHORT...PFANNKUCH
LONG...FAY
AREA FORECAST DISCUSSION
NWS HASTINGS NE
721 AM CDT TUE APR 3 2012
.UPDATE...JUST UPDATED FORECAST TO BRING THINGS IN LINE WITH THE
LATEST TRENDS FOR TODAY...AND ALSO TO DROP PRE-FIRST PERIOD
WORDING IN ZFP PRODUCT. WHAT WAS A NARROW LINE OF THUNDERSTORMS A
FEW HOURS AGO LIFTING NORTH OUT OF KS INTO SOUTHERN NEB HAS SINCE
FADED AWAY INTO A BENIGN LINE OF SPRINKLES CENTERED OVER THE
SHERMAN-DAWSON COUNTY AREA. ALTHOUGH NOT EXPECTING THIS TO REMAIN
IN THE CWA MUCH LONGER...OPTED TO GO AHEAD AND EXPAND A SPRINKLE
MENTION THROUGH THE DAY TO ALL AREAS THAT DIDNT ALREADY HAVE A
MEASURABLE POP. MAIN FAIRLY MINOR CHANGE FROM ORIGINAL FORECAST
ISSUANCE WAS TO PULL ISOLATED THUNDER MENTION COMPLETELY THIS
MORNING...BUT WILL HOLD ONTO THAT MENTION FOR THE AFTERNOON
ALTHOUGH CONFIDENCE IS LOW. ALSO...EXPANDED A MEASURABLE SLIGHT
POP TO MOST OF THE WESTERN CWA FOR THIS AFTERNOON TO ACCOUNT FOR
HINTS OF A BIT MORE ISOLATED SHOWER ACTIVITY THAN EARLIER EXPECTED
PER THE 09Z HRRR. OTHERWISE...MAIN THEME OF FORECAST REMAINS
INTACT...IN THAT THE MAIN SHOW RAIN WISE WILL HOLD OFF UNTIL
TONIGHT INTO TOMORROW. MADE NO CHANGES TO TODAYS HIGH TEMPERATURE
GRID AT THIS TIME.
&&
.PREV DISCUSSION... /ISSUED 533 AM CDT TUE APR 3 2012/
AVIATION...12Z TAF. A NARROW LINE OF RAIN SHOWERS AND A HIT OR
MISS LIGHTNING STRIKE WAS LIFTING TO THE NORTH AND WEST TOWARD
INTERSTATE 80 EARLY THIS MORNING WITH PROGRESSION BEGINNING TO
SLOWER WITH DRIER AIR TO THE NORTH. HAVE NOT INCLUDED ANY PCPN IN
KGRI TAF EARLY THIS MORNING AS EXPECTATION IS THAT ACTIVITY WILL
REMAIN TO THE SOUTH. CLOUDS WILL HOLD FIRM WITH OVERCAST
CONDITIONS EXPECTED THRU THE ENTIRE 24HR TAF DURATION. CIGS ATTM
ARE BORDERLINE BETWEEN IFR AND MVFR AND EXPECT MAINLY PREVAILING
MVFR CIGS OVERALL. AN UPPER LOW PRESSURE SYSTEM WILL EDGE TOWARD
WEST TEXAS THRU TONIGHT AND RAIN SHOWERS WILL BEGIN TO SPREAD
NORTH TOWARD NEBRASKA OVERNIGHT. KGRI WILL BE ON THE NORTHERN EDGE
OF THE RAINFALL TOWARD 12Z.
PREV DISCUSSION... /ISSUED 355 AM CDT TUE APR 3 2012/
SHORT TERM...THROUGH THURSDAY NIGHT. PRIMARY CHALLENGE OVER THE
NEXT 72 HOURS IS CLEARLY RAINFALL TRENDS/AMOUNTS...AS THE MID
LEVEL LOW CURRENTLY CENTERED OVER EASTERN NEW MEXICO GRADUALLY
LUMBERS EASTWARD NEAR THE OK/KS BORDER...AND EVENTUALLY INTO THE
MID-SOUTH BY THURSDAY. CERTAINLY PARTS OF THE CWA ARE GOING TO SEE
SOME WELL-TIMED BENEFICIAL RAINS IN EXCESS OF 0.75-INCH. ALSO NOT
GOING TO SEE MUCH SUNSHINE FOR THE NEXT FEW DAYS.
STARTING OFF EARLY THIS MORNING...08Z OBJECTIVE SURFACE ANALYSIS
SHOWS THE CWA LOCATED WELL NORTH OF THE PRIMARY SURFACE COLD FRONT
STRETCHED NORTHEAST ACROSS SOUTHEAST KANSAS FROM A FAIRLY WEAK LOW
OVER THE TX PANHANDLE. WELL OFF TO THE NORTHWEST...A
BROAD...ROUGHLY 1025 MB HIGH PRESSURE SYSTEM IS CENTERED ACROSS
THE NORTHERN ROCKIES INTO ND. WITH THE CWA POSITIONED WITHIN THE
HEART OF THE MAIN NORTH-SOUTH SURFACE PRESSURE GRADIENT...STEADY
NORTH WINDS HAVE PREVAILED ALL NIGHT...WITH SUSTAINED SPEEDS
COMMONLY 20-30 MPH WITH HIGHER GUSTS...BUT GENERALLY FALLING SHORT
OF WIND ADVISORY CRITERIA IN MOST PLACES. RADAR...11-3.9 MICRON
SATELLITE IMAGERY AND AUTOMATED OBS DEPICT A CORRIDOR OF
WIDESPREAD SHOWERS AND EMBEDDED THUNDERSTORMS CENTERED OVER
CENTRAL/NORTHWEST KANSAS...WITH SOME OF THIS ACTIVITY STARTING TO
INCREASINGLY AFFECT AREAS MAINLY SOUTHWEST OF A BEAVER CITY-BELOIT
LINE. AS FOR RAINFALL AMOUNTS IN THE PAST 12 HOURS...RADAR
ESTIMATES THAT POCKETS OF THE SOUTHERN CWA...MAINLY THE KS
COUNTIES...HAVE LIKELY TALLIED BETWEEN 0.25-0.50 INCH...ALTHOUGH
MOST AREAS PROBABLY LESS. OTHERWISE...AN EXPANSIVE AREA OF LOW
STRATUS MAINLY IN THE 800-1800 FT RANGE HAS OVERTAKEN THE ENTIRE
CWA...WITH JUST A HINT OF LIGHT DRIZZLE IN THE AIR HERE AT THE
WFO. UP TOP...WATER VAPOR SATELLITE CLEARLY DEPICTS THE
AFOREMENTIONED CLOSED LOW CENTERED NEAR THE NM/TX BORDER...WHILE A
RATHER PRONOUNCED RIDGE DOMINATES MUCH OF THE EASTERN CONUS.
GETTING TO THE FORECAST AND STARTING WITH TODAY...IMMEDIATE SHORT
TERM ISSUE OVER THE NEXT 4-6 HOURS IS PROGRESSION OF NEXT BATCH OF
GENERALLY WEAK CONVECTION RIDING UP INTO SOUTHERN ZONES. WILL BE
ISSUING A PRE-FIRST PERIOD ZONE FORECAST PACKAGE...WITH LIKELY
POPS THROUGH 12Z FOR LOCATIONS MAINLY SOUTH OF A BEAVER CITY-
BELOIT LINE. WITH RUC ADVERTISING AT LEAST 500 J/KG MUCAPE IN
THESE AREAS...OCCASIONAL SMALL HAIL AND BRIEF BUT FREQUENT
LIGHTNING STRIKES CERTAINLY ARE POSSIBLE EARLY THIS MORNING.
OTHERWISE...FOLLOWING LATEST HRRR REFLECTIVITY PROGS...ALONG WITH
00Z 4KM WRF-NMM....MUCH OF THIS ACTIVITY SHOULD DECREASE IN
COVERAGE...AND FAIL TO PUSH VERY FAR INTO THE NEB CWA OVER THE
NEXT FEW HOURS AS THE SMALL SCALE SHORTWAVE CURRENTLY OVER
NORTHWEST KS ROTATES BACK MORE TO THE WEST-NORTHWEST.
MOVING ON TO THE DAYTIME 12Z-00Z TIME FRAME...ASSUMING THAT THE
CURRENT CONVECTION DISSIPATES OR MOVES OUT BY AROUND
SUNRISE...REALLY NOT EXPECTING A WHOLE LOT OF PRECIP POTENTIAL FOR
THE MAJORITY OF THE CWA...AS THE LOCAL AREA REMAINS IN A BIT OF A
LULL IN BETWEEN PUSHES OF MID/UPPER FORCING...WAITING FOR THE NEXT
PRIMARY CHUNK OF ENERGY TO ROTATE NORTHWARD OUT OF THE SOUTHERN
PLAINS AHEAD OF THE UPPER LOW. AS A RESULT...ACTUALLY HAVE NO
PRECIPITATION MENTIONED WHATSOEVER ACROSS ROUGHLY THE NORTHEAST
1/2 OF THE CWA THROUGH THE DAY...AND ONLY 20-50 PERCENT POPS
ACROSS SOUTHWEST ZONES...WITH EVEN THIS POTENTIALLY BEING TOO
MUCH. EVEN IN AREAS WITH NO EXPECTATION OF MEASURABLE
PRECIP...SUPPOSE SOME PATCHY DRIZZLE COULD CONTINUE PAST
SUNRISE...BUT WILL LEAVE IT OUT FOR NOW AND TAKE ANOTHER LOOK ON
UPDATE IN A FEW HOURS. IF ANY CONVECTION DOES SURVIVE/MOVE IN
DURING THE DAY...ISOLATED THUNDER POTENTIAL IS CERTAINLY THERE
WITH CONTINUED MUCAPE AVERAGING GENERALLY BELOW 500 J/KG...BUT
POSSIBLY COULD BE ENOUGH TO GENERATE SOME SMALL HAIL. AS FOR HIGH
TEMPS TODAY...FEEL THAT AT LEAST SLIGHTLY UNDERCUTTING MET/MAV
GUIDANCE CONSENSUS IS THE WAY TO GO...AS LOW CLOUDS AND STEADY
NORTHERLY BREEZES OF 15-25 MPH WILL PERSIST THROUGH THE DAY. MAY
STILL BE TOO WARM IN SPOTS...BUT FOR NOW WILL AIM FOR MID-UPPER
50S IN MOST WESTERN AREAS...AND MAYBE SOME LOW 60S IN THE EAST. IN
STARK CONTRAST TO THE PAST SEVERAL WEEKS...THESE HIGHS WOULD BE
VERY NEAR IF NOT SLIGHTLY BELOW NORMAL FOR A CHANGE.
THIS EVENING/TONIGHT...THIS IS WHEN LEGITIMATE WIDESPREAD RAINFALL
WILL RAMP UP...BUT MAINLY ACROSS THE SOUTHERN 1/2 OF THE CWA. IN
SHORT...UPPER DIVERGENCE INCREASES TO THE NORTH OF THE PARENT MID
LEVEL LOW...WHICH WILL BE CENTERED GENERALLY OVER THE OK
PANHANDLE. IN RESPONSE...A CLASSIC...GENERALLY EAST-WEST BAND OF
STEADY SHOWERS AND POSSIBLY SOME EMBEDDED WEAK THUNDERSTORMS WILL
GRADUALLY LIFT NORTH ACROSS KS THIS EVENING...AND HAVE POPS PRIOR
TO 06Z RANGING FROM ONLY 20 PERCENT NEAR KGRI...TO 90 PERCENT IN
MOST OF NORTH CENTRAL KS WHERE THE MAIN PRECIP AXIS WILL SET UP.
FOR THE LATE NIGHT PERIOD...THEN HAVE HIGH 70-90 POPS EXPANDING
NORTHWARD OUT OF KS INTO MUCH OF SOUTH CENTRAL NEB...BUT MAINLY
SOUTH OF I-80. GIVEN TRENDS OF LATEST 06Z NAM...ALONG WITH 4KM
WRF-NMM...AM STARTING TO WONDER IF NORTHERN COUNTIES SUCH AS
VALLEY/NANCE ETC. WILL SEE MUCH OF ANYTHING BEFORE SUNRISE WED
MORNING...AND A TIGHTER POP GRADIENT BETWEEN THE HAVES AND HAVE
NOTS MAY PROVE NECESSARY. AS FOR RAINFALL AMOUNTS...EXPECT AT
LEAST THE SOUTHERN 1/2 TO 1/3 OF THE CWA TO MEASURE BETWEEN
0.25-0.75 INCH OVERNIGHT...WITH LOCALLY HIGHER AMOUNTS
POSSIBLE...AND AGAIN...A FAIRLY SHARP CUTOFF LIKELY SOMEWHERE NEAR
I-80. ALTHOUGH CERTAINLY NOT EXPECTING SEVERE WEATHER...WILL KEEP
ISOLATED THUNDER MENTION OVERNIGHT MAINLY ACROSS THE SOUTHERN 1/3
OF THE CWA...BUT EVEN SMALL HAIL SHOULD BE HARD TO COME BY.
WEDNESDAY...FAIRLY WIDESPREAD RAIN SHOWERS WILL CONTINUE AS THE
PARENT MID LEVEL CIRCULATION TRAVERSES EASTWARD NEAR OR JUST SOUTH
OF THE KS/OK BORDER. KEPT A BROAD AREA OF LIKELY POPS GOING CWA-
WIDE THROUGH THE DAY...ALTHOUGH LATEST NAM/ECWMF CONTINUE TO
SUGGEST THAT THE NORTHERN 1/4 OR SO OF THE CWA...GENERALLY NORTH
OF HWY 92...COULD STRUGGLE TO SEE MUCH...AND POPS IN THESE AREAS
INCLUDING ORD/GREELEY MAY NEED TONED DOWN IN LATER FORECASTS. WITH
WIDESPREAD CLOUDS/ONGOING PRECIP...LOWERED HIGH TEMPS 2-4 DEGREES
IN MOST AREAS FROM PREVIOUS FORECAST...WITH ONLY LOW-MID 50S MOST
AREAS.
WEDNESDAY NIGHT...SHOWERS SHOULD GRADUALLY END FROM NORTHWEST-
SOUTHEAST AS THE PARENT LOW PROGRESSES TO NEAR THE OK/AR
BORDER...AND IT MAY VERY WELL END UP THAT MOST OF THE
CWA...ESPECIALLY THE NORTHWEST 1/2...COULD STAY HIGH AND DRY
THROUGH THE NIGHT. FOR NOW THOUGH WILL CONTINUE 20-40 POPS
CWA-WIDE.
THURSDAY...WILL CONTINUE TO KEEP IT DRY...RUNNING WITH THE
ASSUMPTION THAT THE DEPARTING SYSTEM SHOULD BE FAR ENOUGH
AWAY...ALTHOUGH SUPPOSE A FEW LIGHT WRAP AROUND SHOWERS COULD
FLIRT WITH PARTS OF THE KS CWA. WITH AT LEAST PARTIAL SUNSHINE
EXPECTED TO RETURN...TEMPS ARE FORECAST TO REBOUND BACK INTO THE
LOW-MID 60S FOR HIGHS...BUT AM STAYING JUST BELOW THE MET/MAV
GUIDANCE BLEND FOR NOW. AS SURFACE HIGH PRESSURE SLIDES EAST
.EAST-SOUTHEAST WINDS WILL PICK UP A BIT AS THE DAY WEARS ON.
THURSDAY NIGHT...WILL ALSO MAINTAIN A DRY FORECAST...ALTHOUGH BOTH
THE NAM/GFS ARE DEPICTING CONSIDERABLE LOW LEVEL SATURATION AND
POSSIBLE DRIZZLE POTENTIAL MAINLY ACROSS WESTERN NEB/KS...BUT FOR
NOW MOST IF NOT ALL OF THIS POTENTIAL LOOKS TO REMAIN WEST OF THE
CWA THROUGH THE NIGHT.
ALTHOUGH NOT IN THE FORECAST GRIDS AT THIS TIME...SUPPOSE SOME
FOG REDUCING VISIBILITY AT LEAST INTO THE 1-2 MILE RANGE IS
POSSIBLE ACROSS PARTS OF THE AREA EACH OF THE NEXT 3 NIGHTS...BUT
WITH PRECIP GENERALLY EXPECTED TO BE FAIRLY WIDESPREAD AT LEAST
THE NEXT 2 NIGHTS...NOT LOOKING LIKE AN OBVIOUS SETUP FOR
WIDESPREAD...IMPACTFUL FOG.
IN CLOSING...THIS SYSTEM WILL UNDOUBTEDLY BE A BENEFICIAL
RAINER IN MANY AREAS...HELPING MAKE UP FOR A MARCH PRECIP DEFICIT.
HOWEVER...THERE WILL LIKELY BE A SHARP NORTH-SOUTH RANGE IN
RAINFALL AMOUNTS OVER THE NEXT 24-48 HOURS...WITH CURRENT FORECAST
GRIDS AIMING FOR TOTALS RANGING FROM AT LEAST 1 TO 1.5 INCHES FOR
MOST AREAS NEAR/SOUTH OF I-80...BUT ONLY 0.25-0.50 INCH...AND
MAYBE NOT EVEN THAT MUCH...FOR SOME NORTHERN COUNTIES.
LONG TERM...FRIDAY THROUGH MONDAY. BEGINNING ON FRIDAY AN UPPER
LOW IS FORECAST TO BE CENTERED IN THE PACIFIC NW WITH TROUGH AXIS
EXTENDING THRU THE CENTRAL ROCKIES. IN SOUTHWEST FLOW ALOFT ACROSS
THE CENTRAL PLAINS...SFC TROUGH DEEPENS ALONG THE HIGH PLAINS. AS
SFC GRADIENT TIGHTENS SOUTHERLY WINDS WILL INCREASE WITH BREEZY
CONDITIONS SETTING UP BY AFTN AND MOISTURE WILL WORK NORTHWARD WITH
DPS RISING DURING THE AFTN. ALTHOUGH MAIN FORCING WILL ARRIVE
FRIDAY NIGHT AS UPPER SYSTEM LIFTS ACROSS THE NORTHERN PLAINS AND
ASSOCIATED COLD FRONT CROSS OUR REGION...MODELS DO INDICATE SOME
THETA E ADVECTION FRIDAY AHEAD OF SYSTEM AND WILL MAINTAIN OUR
CURRENT LOW POPS DURING THE DAY FRIDAY. AS FRONT CROSSES FRIDAY
NIGHT THERE IS A NARROW AXIS OF INSTABILITY ALONG/AHEAD OF
BOUNDARY...MUCAPES NEARING 1000 J/KG...AND COULD POTENTIALLY SEE A
STRONG STORM OR TWO.
EASTER WEEKEND IS SHAPING UP TO BE DRY AND SEASONAL OVERALL. A
1030MB SURFACE HIGH BUILDS SOUTH BEING THE FRONT AND SETTLES ACROSS
THE CENTRAL PLAINS OVERNIGHT. SFC DPS ARE PROGGED TO DROP TO THE
TEENS IN OUR NW WITH 20S IN THE SOUTHEAST IN THE DRY AIRMASS.
LOOKING LIKE A MUCH COLDER NIGHT THAN WE HAVE HAD RECENTLY HOWEVER
NOT NECESSARILY UNUSUAL FOR THIS TIME OF YEAR WITH NORMAL LOWS IN
THE LOW/MID 30S. FORECAST LOWS ARE IN THE 30S IN GENERAL AND AGREE
PREVIOUS SHIFTS THAT THIS PERIOD WILL NEED TO BE MONITORED FOR
FROST/FREEZE POTENTIAL.
SURFACE RIDGE AXIS SLIPS SOUTHEAST ON SUNDAY WITH RETURN FLOW
SETTING UP DURING THE DAY. ANOTHER COLD FRONT CROSSES THE PLAINS
SUNDAY NIGHT/MONDAY ASSOCIATED WITH UPPER LOW IN ONTARIO AND TROUGH
EXTENDING ACROSS THE UPPER MIDWEST/OHIO VALLEY REGION. BRUNT OF
COLD AIR REMAINS EAST OF THE MISSOURI RIVER...HOWEVER SOME COOLER
AIR DOES BACK INTO OUR NORTHEAST COUNTIES. THIS BEING
SAID...ALTHOUGH HIGHS MAY DROP A DEGREE OR TWO FROM SUNDAY...TEMPS
OVERALL ARE STILL LOOKING SEASONAL OR SLIGHTLY ABOVE.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE/SHORT TERM...PFANNKUCH
LONG TERM/AVIATION...CF
AREA FORECAST DISCUSSION
NWS HASTINGS NE
533 AM CDT TUE APR 3 2012
.AVIATION...12Z TAF. A NARROW LINE OF RAIN SHOWERS AND A HIT OR
MISS LIGHTNING STRIKE WAS LIFTING TO THE NORTH AND WEST TOWARD
INTERSTATE 80 EARLY THIS MORNING WITH PROGRESSION BEGINNING TO
SLOWER WITH DRIER AIR TO THE NORTH. HAVE NOT INCLUDED ANY PCPN IN
KGRI TAF EARLY THIS MORNING AS EXPECTATION IS THAT ACTIVITY WILL
REMAIN TO THE SOUTH. CLOUDS WILL HOLD FIRM WITH OVERCAST
CONDITIONS EXPECTED THRU THE ENTIRE 24HR TAF DURATION. CIGS ATTM
ARE BORDERLINE BETWEEN IFR AND MVFR AND EXPECT MAINLY PREVAILING
MVFR CIGS OVERALL. AN UPPER LOW PRESSURE SYSTEM WILL EDGE TOWARD
WEST TEXAS THRU TONIGHT AND RAIN SHOWERS WILL BEGIN TO SPREAD
NORTH TOWARD NEBRASKA OVERNIGHT. KGRI WILL BE ON THE NORTHERN EDGE
OF THE RAINFALL TOWARD 12Z.
&&
.PREV DISCUSSION... /ISSUED 355 AM CDT TUE APR 3 2012/
SHORT TERM...THROUGH THURSDAY NIGHT. PRIMARY CHALLENGE OVER THE
NEXT 72 HOURS IS CLEARLY RAINFALL TRENDS/AMOUNTS...AS THE MID
LEVEL LOW CURRENTLY CENTERED OVER EASTERN NEW MEXICO GRADUALLY
LUMBERS EASTWARD NEAR THE OK/KS BORDER...AND EVENTUALLY INTO THE
MID-SOUTH BY THURSDAY. CERTAINLY PARTS OF THE CWA ARE GOING TO SEE
SOME WELL-TIMED BENEFICIAL RAINS IN EXCESS OF 0.75-INCH. ALSO NOT
GOING TO SEE MUCH SUNSHINE FOR THE NEXT FEW DAYS.
STARTING OFF EARLY THIS MORNING...08Z OBJECTIVE SURFACE ANALYSIS
SHOWS THE CWA LOCATED WELL NORTH OF THE PRIMARY SURFACE COLD FRONT
STRETCHED NORTHEAST ACROSS SOUTHEAST KANSAS FROM A FAIRLY WEAK LOW
OVER THE TX PANHANDLE. WELL OFF TO THE NORTHWEST...A
BROAD...ROUGHLY 1025 MB HIGH PRESSURE SYSTEM IS CENTERED ACROSS
THE NORTHERN ROCKIES INTO ND. WITH THE CWA POSITIONED WITHIN THE
HEART OF THE MAIN NORTH-SOUTH SURFACE PRESSURE GRADIENT...STEADY
NORTH WINDS HAVE PREVAILED ALL NIGHT...WITH SUSTAINED SPEEDS
COMMONLY 20-30 MPH WITH HIGHER GUSTS...BUT GENERALLY FALLING SHORT
OF WIND ADVISORY CRITERIA IN MOST PLACES. RADAR...11-3.9 MICRON
SATELLITE IMAGERY AND AUTOMATED OBS DEPICT A CORRIDOR OF
WIDESPREAD SHOWERS AND EMBEDDED THUNDERSTORMS CENTERED OVER
CENTRAL/NORTHWEST KANSAS...WITH SOME OF THIS ACTIVITY STARTING TO
INCREASINGLY AFFECT AREAS MAINLY SOUTHWEST OF A BEAVER CITY-BELOIT
LINE. AS FOR RAINFALL AMOUNTS IN THE PAST 12 HOURS...RADAR
ESTIMATES THAT POCKETS OF THE SOUTHERN CWA...MAINLY THE KS
COUNTIES...HAVE LIKELY TALLIED BETWEEN 0.25-0.50 INCH...ALTHOUGH
MOST AREAS PROBABLY LESS. OTHERWISE...AN EXPANSIVE AREA OF LOW
STRATUS MAINLY IN THE 800-1800 FT RANGE HAS OVERTAKEN THE ENTIRE
CWA...WITH JUST A HINT OF LIGHT DRIZZLE IN THE AIR HERE AT THE
WFO. UP TOP...WATER VAPOR SATELLITE CLEARLY DEPICTS THE
AFOREMENTIONED CLOSED LOW CENTERED NEAR THE NM/TX BORDER...WHILE A
RATHER PRONOUNCED RIDGE DOMINATES MUCH OF THE EASTERN CONUS.
GETTING TO THE FORECAST AND STARTING WITH TODAY...IMMEDIATE SHORT
TERM ISSUE OVER THE NEXT 4-6 HOURS IS PROGRESSION OF NEXT BATCH OF
GENERALLY WEAK CONVECTION RIDING UP INTO SOUTHERN ZONES. WILL BE
ISSUING A PRE-FIRST PERIOD ZONE FORECAST PACKAGE...WITH LIKELY
POPS THROUGH 12Z FOR LOCATIONS MAINLY SOUTH OF A BEAVER CITY-
BELOIT LINE. WITH RUC ADVERTISING AT LEAST 500 J/KG MUCAPE IN
THESE AREAS...OCCASIONAL SMALL HAIL AND BRIEF BUT FREQUENT
LIGHTNING STRIKES CERTAINLY ARE POSSIBLE EARLY THIS MORNING.
OTHERWISE...FOLLOWING LATEST HRRR REFLECTIVITY PROGS...ALONG WITH
00Z 4KM WRF-NMM....MUCH OF THIS ACTIVITY SHOULD DECREASE IN
COVERAGE...AND FAIL TO PUSH VERY FAR INTO THE NEB CWA OVER THE
NEXT FEW HOURS AS THE SMALL SCALE SHORTWAVE CURRENTLY OVER
NORTHWEST KS ROTATES BACK MORE TO THE WEST-NORTHWEST.
MOVING ON TO THE DAYTIME 12Z-00Z TIME FRAME...ASSUMING THAT THE
CURRENT CONVECTION DISSIPATES OR MOVES OUT BY AROUND
SUNRISE...REALLY NOT EXPECTING A WHOLE LOT OF PRECIP POTENTIAL FOR
THE MAJORITY OF THE CWA...AS THE LOCAL AREA REMAINS IN A BIT OF A
LULL IN BETWEEN PUSHES OF MID/UPPER FORCING...WAITING FOR THE NEXT
PRIMARY CHUNK OF ENERGY TO ROTATE NORTHWARD OUT OF THE SOUTHERN
PLAINS AHEAD OF THE UPPER LOW. AS A RESULT...ACTUALLY HAVE NO
PRECIPITATION MENTIONED WHATSOEVER ACROSS ROUGHLY THE NORTHEAST
1/2 OF THE CWA THROUGH THE DAY...AND ONLY 20-50 PERCENT POPS
ACROSS SOUTHWEST ZONES...WITH EVEN THIS POTENTIALLY BEING TOO
MUCH. EVEN IN AREAS WITH NO EXPECTATION OF MEASURABLE
PRECIP...SUPPOSE SOME PATCHY DRIZZLE COULD CONTINUE PAST
SUNRISE...BUT WILL LEAVE IT OUT FOR NOW AND TAKE ANOTHER LOOK ON
UPDATE IN A FEW HOURS. IF ANY CONVECTION DOES SURVIVE/MOVE IN
DURING THE DAY...ISOLATED THUNDER POTENTIAL IS CERTAINLY THERE
WITH CONTINUED MUCAPE AVERAGING GENERALLY BELOW 500 J/KG...BUT
POSSIBLY COULD BE ENOUGH TO GENERATE SOME SMALL HAIL. AS FOR HIGH
TEMPS TODAY...FEEL THAT AT LEAST SLIGHTLY UNDERCUTTING MET/MAV
GUIDANCE CONSENSUS IS THE WAY TO GO...AS LOW CLOUDS AND STEADY
NORTHERLY BREEZES OF 15-25 MPH WILL PERSIST THROUGH THE DAY. MAY
STILL BE TOO WARM IN SPOTS...BUT FOR NOW WILL AIM FOR MID-UPPER
50S IN MOST WESTERN AREAS...AND MAYBE SOME LOW 60S IN THE EAST. IN
STARK CONTRAST TO THE PAST SEVERAL WEEKS...THESE HIGHS WOULD BE
VERY NEAR IF NOT SLIGHTLY BELOW NORMAL FOR A CHANGE.
THIS EVENING/TONIGHT...THIS IS WHEN LEGITIMATE WIDESPREAD RAINFALL
WILL RAMP UP...BUT MAINLY ACROSS THE SOUTHERN 1/2 OF THE CWA. IN
SHORT...UPPER DIVERGENCE INCREASES TO THE NORTH OF THE PARENT MID
LEVEL LOW...WHICH WILL BE CENTERED GENERALLY OVER THE OK
PANHANDLE. IN RESPONSE...A CLASSIC...GENERALLY EAST-WEST BAND OF
STEADY SHOWERS AND POSSIBLY SOME EMBEDDED WEAK THUNDERSTORMS WILL
GRADUALLY LIFT NORTH ACROSS KS THIS EVENING...AND HAVE POPS PRIOR
TO 06Z RANGING FROM ONLY 20 PERCENT NEAR KGRI...TO 90 PERCENT IN
MOST OF NORTH CENTRAL KS WHERE THE MAIN PRECIP AXIS WILL SET UP.
FOR THE LATE NIGHT PERIOD...THEN HAVE HIGH 70-90 POPS EXPANDING
NORTHWARD OUT OF KS INTO MUCH OF SOUTH CENTRAL NEB...BUT MAINLY
SOUTH OF I-80. GIVEN TRENDS OF LATEST 06Z NAM...ALONG WITH 4KM
WRF-NMM...AM STARTING TO WONDER IF NORTHERN COUNTIES SUCH AS
VALLEY/NANCE ETC. WILL SEE MUCH OF ANYTHING BEFORE SUNRISE WED
MORNING...AND A TIGHTER POP GRADIENT BETWEEN THE HAVES AND HAVE
NOTS MAY PROVE NECESSARY. AS FOR RAINFALL AMOUNTS...EXPECT AT
LEAST THE SOUTHERN 1/2 TO 1/3 OF THE CWA TO MEASURE BETWEEN
0.25-0.75 INCH OVERNIGHT...WITH LOCALLY HIGHER AMOUNTS
POSSIBLE...AND AGAIN...A FAIRLY SHARP CUTOFF LIKELY SOMEWHERE NEAR
I-80. ALTHOUGH CERTAINLY NOT EXPECTING SEVERE WEATHER...WILL KEEP
ISOLATED THUNDER MENTION OVERNIGHT MAINLY ACROSS THE SOUTHERN 1/3
OF THE CWA...BUT EVEN SMALL HAIL SHOULD BE HARD TO COME BY.
WEDNESDAY...FAIRLY WIDESPREAD RAIN SHOWERS WILL CONTINUE AS THE
PARENT MID LEVEL CIRCULATION TRAVERSES EASTWARD NEAR OR JUST SOUTH
OF THE KS/OK BORDER. KEPT A BROAD AREA OF LIKELY POPS GOING CWA-
WIDE THROUGH THE DAY...ALTHOUGH LATEST NAM/ECWMF CONTINUE TO
SUGGEST THAT THE NORTHERN 1/4 OR SO OF THE CWA...GENERALLY NORTH
OF HWY 92...COULD STRUGGLE TO SEE MUCH...AND POPS IN THESE AREAS
INCLUDING ORD/GREELEY MAY NEED TONED DOWN IN LATER FORECASTS. WITH
WIDESPREAD CLOUDS/ONGOING PRECIP...LOWERED HIGH TEMPS 2-4 DEGREES
IN MOST AREAS FROM PREVIOUS FORECAST...WITH ONLY LOW-MID 50S MOST
AREAS.
WEDNESDAY NIGHT...SHOWERS SHOULD GRADUALLY END FROM NORTHWEST-
SOUTHEAST AS THE PARENT LOW PROGRESSES TO NEAR THE OK/AR
BORDER...AND IT MAY VERY WELL END UP THAT MOST OF THE
CWA...ESPECIALLY THE NORTHWEST 1/2...COULD STAY HIGH AND DRY
THROUGH THE NIGHT. FOR NOW THOUGH WILL CONTINUE 20-40 POPS
CWA-WIDE.
THURSDAY...WILL CONTINUE TO KEEP IT DRY...RUNNING WITH THE
ASSUMPTION THAT THE DEPARTING SYSTEM SHOULD BE FAR ENOUGH
AWAY...ALTHOUGH SUPPOSE A FEW LIGHT WRAP AROUND SHOWERS COULD
FLIRT WITH PARTS OF THE KS CWA. WITH AT LEAST PARTIAL SUNSHINE
EXPECTED TO RETURN...TEMPS ARE FORECAST TO REBOUND BACK INTO THE
LOW-MID 60S FOR HIGHS...BUT AM STAYING JUST BELOW THE MET/MAV
GUIDANCE BLEND FOR NOW. AS SURFACE HIGH PRESSURE SLIDES EAST
..EAST-SOUTHEAST WINDS WILL PICK UP A BIT AS THE DAY WEARS ON.
THURSDAY NIGHT...WILL ALSO MAINTAIN A DRY FORECAST...ALTHOUGH BOTH
THE NAM/GFS ARE DEPICTING CONSIDERABLE LOW LEVEL SATURATION AND
POSSIBLE DRIZZLE POTENTIAL MAINLY ACROSS WESTERN NEB/KS...BUT FOR
NOW MOST IF NOT ALL OF THIS POTENTIAL LOOKS TO REMAIN WEST OF THE
CWA THROUGH THE NIGHT.
ALTHOUGH NOT IN THE FORECAST GRIDS AT THIS TIME...SUPPOSE SOME
FOG REDUCING VISIBILITY AT LEAST INTO THE 1-2 MILE RANGE IS
POSSIBLE ACROSS PARTS OF THE AREA EACH OF THE NEXT 3 NIGHTS...BUT
WITH PRECIP GENERALLY EXPECTED TO BE FAIRLY WIDESPREAD AT LEAST
THE NEXT 2 NIGHTS...NOT LOOKING LIKE AN OBVIOUS SETUP FOR
WIDESPREAD...IMPACTFUL FOG.
IN CLOSING...THIS SYSTEM WILL UNDOUBTEDLY BE A BENEFICIAL
RAINER IN MANY AREAS...HELPING MAKE UP FOR A MARCH PRECIP DEFICIT.
HOWEVER...THERE WILL LIKELY BE A SHARP NORTH-SOUTH RANGE IN
RAINFALL AMOUNTS OVER THE NEXT 24-48 HOURS...WITH CURRENT FORECAST
GRIDS AIMING FOR TOTALS RANGING FROM AT LEAST 1 TO 1.5 INCHES FOR
MOST AREAS NEAR/SOUTH OF I-80...BUT ONLY 0.25-0.50 INCH...AND
MAYBE NOT EVEN THAT MUCH...FOR SOME NORTHERN COUNTIES.
LONG TERM...FRIDAY THROUGH MONDAY. BEGINNING ON FRIDAY AN UPPER
LOW IS FORECAST TO BE CENTERED IN THE PACIFIC NW WITH TROUGH AXIS
EXTENDING THRU THE CENTRAL ROCKIES. IN SOUTHWEST FLOW ALOFT ACROSS
THE CENTRAL PLAINS...SFC TROUGH DEEPENS ALONG THE HIGH PLAINS. AS
SFC GRADIENT TIGHTENS SOUTHERLY WINDS WILL INCREASE WITH BREEZY
CONDITIONS SETTING UP BY AFTN AND MOISTURE WILL WORK NORTHWARD WITH
DPS RISING DURING THE AFTN. ALTHOUGH MAIN FORCING WILL ARRIVE
FRIDAY NIGHT AS UPPER SYSTEM LIFTS ACROSS THE NORTHERN PLAINS AND
ASSOCIATED COLD FRONT CROSS OUR REGION...MODELS DO INDICATE SOME
THETA E ADVECTION FRIDAY AHEAD OF SYSTEM AND WILL MAINTAIN OUR
CURRENT LOW POPS DURING THE DAY FRIDAY. AS FRONT CROSSES FRIDAY
NIGHT THERE IS A NARROW AXIS OF INSTABILITY ALONG/AHEAD OF
BOUNDARY...MUCAPES NEARING 1000 J/KG...AND COULD POTENTIALLY SEE A
STRONG STORM OR TWO.
EASTER WEEKEND IS SHAPING UP TO BE DRY AND SEASONAL OVERALL. A
1030MB SURFACE HIGH BUILDS SOUTH BEING THE FRONT AND SETTLES ACROSS
THE CENTRAL PLAINS OVERNIGHT. SFC DPS ARE PROGGED TO DROP TO THE
TEENS IN OUR NW WITH 20S IN THE SOUTHEAST IN THE DRY AIRMASS.
LOOKING LIKE A MUCH COLDER NIGHT THAN WE HAVE HAD RECENTLY HOWEVER
NOT NECESSARILY UNUSUAL FOR THIS TIME OF YEAR WITH NORMAL LOWS IN
THE LOW/MID 30S. FORECAST LOWS ARE IN THE 30S IN GENERAL AND AGREE
PREVIOUS SHIFTS THAT THIS PERIOD WILL NEED TO BE MONITORED FOR
FROST/FREEZE POTENTIAL.
SURFACE RIDGE AXIS SLIPS SOUTHEAST ON SUNDAY WITH RETURN FLOW
SETTING UP DURING THE DAY. ANOTHER COLD FRONT CROSSES THE PLAINS
SUNDAY NIGHT/MONDAY ASSOCIATED WITH UPPER LOW IN ONTARIO AND TROUGH
EXTENDING ACROSS THE UPPER MIDWEST/OHIO VALLEY REGION. BRUNT OF
COLD AIR REMAINS EAST OF THE MISSOURI RIVER...HOWEVER SOME COOLER
AIR DOES BACK INTO OUR NORTHEAST COUNTIES. THIS BEING
SAID...ALTHOUGH HIGHS MAY DROP A DEGREE OR TWO FROM SUNDAY...TEMPS
OVERALL ARE STILL LOOKING SEASONAL OR SLIGHTLY ABOVE.
PREV DISCUSSION... /ISSUED 1214 AM CDT TUE APR 3 2012/
AVIATION...06Z TAF. THE TAF PERIOD WILL BE MARKED WITH FAIRLY
WINDY CONDITIONS IN RESPONSE TO A TIGHT PRESSURE GRADIENT
FOLLOWING THE PASSAGE OF A COLD FRONT ON MONDAY. NORTHERLY WINDS
WILL AVERAGE 20KTS OR SO AND GUST NEAR 30KTS. WINDS WILL
TRANSITION NORTHEASTERLY TUESDAY AFTERNOON AND ALTHOUGH STILL
BREEZY...WIND SPEEDS WILL GRADUALLY DECREASE AS THE GRADIENT RELAXES.
IT LOOKS LIKE PRECIPITATION WILL HOLD OFF UNTIL BEYOND THE TAF
PERIOD UNTIL THE SOUTHERN PLAINS LOW LIFTS FARTHER NORTH. CLOUD
COVER FOR THE MOST PART SHOULD BE IN THE MVFR CATEGORY ALTHOUGH
SOME IFR CIGS ARE POSSIBLE TUESDAY MORNING.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...PFANNKUCH
LONG TERM/AVIATION...CF
AREA FORECAST DISCUSSION
NWS HASTINGS NE
355 AM CDT TUE APR 3 2012
.SHORT TERM...THROUGH THURSDAY NIGHT. PRIMARY CHALLENGE OVER THE
NEXT 72 HOURS IS CLEARLY RAINFALL TRENDS/AMOUNTS...AS THE MID
LEVEL LOW CURRENTLY CENTERED OVER EASTERN NEW MEXICO GRADUALLY
LUMBERS EASTWARD NEAR THE OK/KS BORDER...AND EVENTUALLY INTO THE
MID-SOUTH BY THURSDAY. CERTAINLY PARTS OF THE CWA ARE GOING TO SEE
SOME WELL-TIMED BENEFICIAL RAINS IN EXCESS OF 0.75-INCH. ALSO NOT
GOING TO SEE MUCH SUNSHINE FOR THE NEXT FEW DAYS.
STARTING OFF EARLY THIS MORNING...08Z OBJECTIVE SURFACE ANALYSIS
SHOWS THE CWA LOCATED WELL NORTH OF THE PRIMARY SURFACE COLD FRONT
STRETCHED NORTHEAST ACROSS SOUTHEAST KANSAS FROM A FAIRLY WEAK LOW
OVER THE TX PANHANDLE. WELL OFF TO THE NORTHWEST...A
BROAD...ROUGHLY 1025 MB HIGH PRESSURE SYSTEM IS CENTERED ACROSS
THE NORTHERN ROCKIES INTO ND. WITH THE CWA POSITIONED WITHIN THE
HEART OF THE MAIN NORTH-SOUTH SURFACE PRESSURE GRADIENT...STEADY
NORTH WINDS HAVE PREVAILED ALL NIGHT...WITH SUSTAINED SPEEDS
COMMONLY 20-30 MPH WITH HIGHER GUSTS...BUT GENERALLY FALLING SHORT
OF WIND ADVISORY CRITERIA IN MOST PLACES. RADAR...11-3.9 MICRON
SATELLITE IMAGERY AND AUTOMATED OBS DEPICT A CORRIDOR OF
WIDESPREAD SHOWERS AND EMBEDDED THUNDERSTORMS CENTERED OVER
CENTRAL/NORTHWEST KANSAS...WITH SOME OF THIS ACTIVITY STARTING TO
INCREASINGLY AFFECT AREAS MAINLY SOUTHWEST OF A BEAVER CITY-BELOIT
LINE. AS FOR RAINFALL AMOUNTS IN THE PAST 12 HOURS...RADAR
ESTIMATES THAT POCKETS OF THE SOUTHERN CWA...MAINLY THE KS
COUNTIES...HAVE LIKELY TALLIED BETWEEN 0.25-0.50 INCH...ALTHOUGH
MOST AREAS PROBABLY LESS. OTHERWISE...AN EXPANSIVE AREA OF LOW
STRATUS MAINLY IN THE 800-1800 FT RANGE HAS OVERTAKEN THE ENTIRE
CWA...WITH JUST A HINT OF LIGHT DRIZZLE IN THE AIR HERE AT THE
WFO. UP TOP...WATER VAPOR SATELLITE CLEARLY DEPICTS THE
AFOREMENTIONED CLOSED LOW CENTERED NEAR THE NM/TX BORDER...WHILE A
RATHER PRONOUNCED RIDGE DOMINATES MUCH OF THE EASTERN CONUS.
GETTING TO THE FORECAST AND STARTING WITH TODAY...IMMEDIATE SHORT
TERM ISSUE OVER THE NEXT 4-6 HOURS IS PROGRESSION OF NEXT BATCH OF
GENERALLY WEAK CONVECTION RIDING UP INTO SOUTHERN ZONES. WILL BE
ISSUING A PRE-FIRST PERIOD ZONE FORECAST PACKAGE...WITH LIKELY
POPS THROUGH 12Z FOR LOCATIONS MAINLY SOUTH OF A BEAVER CITY-
BELOIT LINE. WITH RUC ADVERTISING AT LEAST 500 J/KG MUCAPE IN
THESE AREAS...OCCASIONAL SMALL HAIL AND BRIEF BUT FREQUENT
LIGHTNING STRIKES CERTAINLY ARE POSSIBLE EARLY THIS MORNING.
OTHERWISE...FOLLOWING LATEST HRRR REFLECTIVITY PROGS...ALONG WITH
00Z 4KM WRF-NMM....MUCH OF THIS ACTIVITY SHOULD DECREASE IN
COVERAGE...AND FAIL TO PUSH VERY FAR INTO THE NEB CWA OVER THE
NEXT FEW HOURS AS THE SMALL SCALE SHORTWAVE CURRENTLY OVER
NORTHWEST KS ROTATES BACK MORE TO THE WEST-NORTHWEST.
MOVING ON TO THE DAYTIME 12Z-00Z TIME FRAME...ASSUMING THAT THE
CURRENT CONVECTION DISSIPATES OR MOVES OUT BY AROUND
SUNRISE...REALLY NOT EXPECTING A WHOLE LOT OF PRECIP POTENTIAL FOR
THE MAJORITY OF THE CWA...AS THE LOCAL AREA REMAINS IN A BIT OF A
LULL IN BETWEEN PUSHES OF MID/UPPER FORCING...WAITING FOR THE NEXT
PRIMARY CHUNK OF ENERGY TO ROTATE NORTHWARD OUT OF THE SOUTHERN
PLAINS AHEAD OF THE UPPER LOW. AS A RESULT...ACTUALLY HAVE NO
PRECIPITATION MENTIONED WHATSOEVER ACROSS ROUGHLY THE NORTHEAST
1/2 OF THE CWA THROUGH THE DAY...AND ONLY 20-50 PERCENT POPS
ACROSS SOUTHWEST ZONES...WITH EVEN THIS POTENTIALLY BEING TOO
MUCH. EVEN IN AREAS WITH NO EXPECTATION OF MEASURABLE
PRECIP...SUPPOSE SOME PATCHY DRIZZLE COULD CONTINUE PAST
SUNRISE...BUT WILL LEAVE IT OUT FOR NOW AND TAKE ANOTHER LOOK ON
UPDATE IN A FEW HOURS. IF ANY CONVECTION DOES SURVIVE/MOVE IN
DURING THE DAY...ISOLATED THUNDER POTENTIAL IS CERTAINLY THERE
WITH CONTINUED MUCAPE AVERAGING GENERALLY BELOW 500 J/KG...BUT
POSSIBLY COULD BE ENOUGH TO GENERATE SOME SMALL HAIL. AS FOR HIGH
TEMPS TODAY...FEEL THAT AT LEAST SLIGHTLY UNDERCUTTING MET/MAV
GUIDANCE CONSENSUS IS THE WAY TO GO...AS LOW CLOUDS AND STEADY
NORTHERLY BREEZES OF 15-25 MPH WILL PERSIST THROUGH THE DAY. MAY
STILL BE TOO WARM IN SPOTS...BUT FOR NOW WILL AIM FOR MID-UPPER
50S IN MOST WESTERN AREAS...AND MAYBE SOME LOW 60S IN THE EAST. IN
STARK CONTRAST TO THE PAST SEVERAL WEEKS...THESE HIGHS WOULD BE
VERY NEAR IF NOT SLIGHTLY BELOW NORMAL FOR A CHANGE.
THIS EVENING/TONIGHT...THIS IS WHEN LEGITIMATE WIDESPREAD RAINFALL
WILL RAMP UP...BUT MAINLY ACROSS THE SOUTHERN 1/2 OF THE CWA. IN
SHORT...UPPER DIVERGENCE INCREASES TO THE NORTH OF THE PARENT MID
LEVEL LOW...WHICH WILL BE CENTERED GENERALLY OVER THE OK
PANHANDLE. IN RESPONSE...A CLASSIC...GENERALLY EAST-WEST BAND OF
STEADY SHOWERS AND POSSIBLY SOME EMBEDDED WEAK THUNDERSTORMS WILL
GRADUALLY LIFT NORTH ACROSS KS THIS EVENING...AND HAVE POPS PRIOR
TO 06Z RANGING FROM ONLY 20 PERCENT NEAR KGRI...TO 90 PERCENT IN
MOST OF NORTH CENTRAL KS WHERE THE MAIN PRECIP AXIS WILL SET UP.
FOR THE LATE NIGHT PERIOD...THEN HAVE HIGH 70-90 POPS EXPANDING
NORTHWARD OUT OF KS INTO MUCH OF SOUTH CENTRAL NEB...BUT MAINLY
SOUTH OF I-80. GIVEN TRENDS OF LATEST 06Z NAM...ALONG WITH 4KM
WRF-NMM...AM STARTING TO WONDER IF NORTHERN COUNTIES SUCH AS
VALLEY/NANCE ETC. WILL SEE MUCH OF ANYTHING BEFORE SUNRISE WED
MORNING...AND A TIGHTER POP GRADIENT BETWEEN THE HAVES AND HAVE
NOTS MAY PROVE NECESSARY. AS FOR RAINFALL AMOUNTS...EXPECT AT
LEAST THE SOUTHERN 1/2 TO 1/3 OF THE CWA TO MEASURE BETWEEN
0.25-0.75 INCH OVERNIGHT...WITH LOCALLY HIGHER AMOUNTS
POSSIBLE...AND AGAIN...A FAIRLY SHARP CUTOFF LIKELY SOMEWHERE NEAR
I-80. ALTHOUGH CERTAINLY NOT EXPECTING SEVERE WEATHER...WILL KEEP
ISOLATED THUNDER MENTION OVERNIGHT MAINLY ACROSS THE SOUTHERN 1/3
OF THE CWA...BUT EVEN SMALL HAIL SHOULD BE HARD TO COME BY.
WEDNESDAY...FAIRLY WIDESPREAD RAIN SHOWERS WILL CONTINUE AS THE
PARENT MID LEVEL CIRCULATION TRAVERSES EASTWARD NEAR OR JUST SOUTH
OF THE KS/OK BORDER. KEPT A BROAD AREA OF LIKELY POPS GOING CWA-
WIDE THROUGH THE DAY...ALTHOUGH LATEST NAM/ECWMF CONTINUE TO
SUGGEST THAT THE NORTHERN 1/4 OR SO OF THE CWA...GENERALLY NORTH
OF HWY 92...COULD STRUGGLE TO SEE MUCH...AND POPS IN THESE AREAS
INCLUDING ORD/GREELEY MAY NEED TONED DOWN IN LATER FORECASTS. WITH
WIDESPREAD CLOUDS/ONGOING PRECIP...LOWERED HIGH TEMPS 2-4 DEGREES
IN MOST AREAS FROM PREVIOUS FORECAST...WITH ONLY LOW-MID 50S MOST
AREAS.
WEDNESDAY NIGHT...SHOWERS SHOULD GRADUALLY END FROM NORTHWEST-
SOUTHEAST AS THE PARENT LOW PROGRESSES TO NEAR THE OK/AR
BORDER...AND IT MAY VERY WELL END UP THAT MOST OF THE
CWA...ESPECIALLY THE NORTHWEST 1/2...COULD STAY HIGH AND DRY
THROUGH THE NIGHT. FOR NOW THOUGH WILL CONTINUE 20-40 POPS
CWA-WIDE.
THURSDAY...WILL CONTINUE TO KEEP IT DRY...RUNNING WITH THE
ASSUMPTION THAT THE DEPARTING SYSTEM SHOULD BE FAR ENOUGH
AWAY...ALTHOUGH SUPPOSE A FEW LIGHT WRAP AROUND SHOWERS COULD
FLIRT WITH PARTS OF THE KS CWA. WITH AT LEAST PARTIAL SUNSHINE
EXPECTED TO RETURN...TEMPS ARE FORECAST TO REBOUND BACK INTO THE
LOW-MID 60S FOR HIGHS...BUT AM STAYING JUST BELOW THE MET/MAV
GUIDANCE BLEND FOR NOW. AS SURFACE HIGH PRESSURE SLIDES EAST
...EAST-SOUTHEAST WINDS WILL PICK UP A BIT AS THE DAY WEARS ON.
THURSDAY NIGHT...WILL ALSO MAINTAIN A DRY FORECAST...ALTHOUGH BOTH
THE NAM/GFS ARE DEPICTING CONSIDERABLE LOW LEVEL SATURATION AND
POSSIBLE DRIZZLE POTENTIAL MAINLY ACROSS WESTERN NEB/KS...BUT FOR
NOW MOST IF NOT ALL OF THIS POTENTIAL LOOKS TO REMAIN WEST OF THE
CWA THROUGH THE NIGHT.
ALTHOUGH NOT IN THE FORECAST GRIDS AT THIS TIME...SUPPOSE SOME
FOG REDUCING VISIBILITY AT LEAST INTO THE 1-2 MILE RANGE IS
POSSIBLE ACROSS PARTS OF THE AREA EACH OF THE NEXT 3 NIGHTS...BUT
WITH PRECIP GENERALLY EXPECTED TO BE FAIRLY WIDESPREAD AT LEAST
THE NEXT 2 NIGHTS...NOT LOOKING LIKE AN OBVIOUS SETUP FOR
WIDESPREAD...IMPACTFUL FOG.
IN CLOSING...THIS SYSTEM WILL UNDOUBTEDLY BE A BENEFICIAL
RAINER IN MANY AREAS...HELPING MAKE UP FOR A MARCH PRECIP DEFICIT.
HOWEVER...THERE WILL LIKELY BE A SHARP NORTH-SOUTH RANGE IN
RAINFALL AMOUNTS OVER THE NEXT 24-48 HOURS...WITH CURRENT FORECAST
GRIDS AIMING FOR TOTALS RANGING FROM AT LEAST 1 TO 1.5 INCHES FOR
MOST AREAS NEAR/SOUTH OF I-80...BUT ONLY 0.25-0.50 INCH...AND
MAYBE NOT EVEN THAT MUCH...FOR SOME NORTHERN COUNTIES.
.LONG TERM...FRIDAY THROUGH MONDAY. BEGINNING ON FRIDAY AN UPPER
LOW IS FORECAST TO BE CENTERED IN THE PACIFIC NW WITH TROUGH AXIS
EXTENDING THRU THE CENTRAL ROCKIES. IN SOUTHWEST FLOW ALOFT ACROSS
THE CENTRAL PLAINS...SFC TROUGH DEEPENS ALONG THE HIGH PLAINS. AS
SFC GRADIENT TIGHTENS SOUTHERLY WINDS WILL INCREASE WITH BREEZY
CONDITIONS SETTING UP BY AFTN AND MOISTURE WILL WORK NORTHWARD WITH
DPS RISING DURING THE AFTN. ALTHOUGH MAIN FORCING WILL ARRIVE
FRIDAY NIGHT AS UPPER SYSTEM LIFTS ACROSS THE NORTHERN PLAINS AND
ASSOCIATED COLD FRONT CROSS OUR REGION...MODELS DO INDICATE SOME
THETA E ADVECTION FRIDAY AHEAD OF SYSTEM AND WILL MAINTAIN OUR
CURRENT LOW POPS DURING THE DAY FRIDAY. AS FRONT CROSSES FRIDAY
NIGHT THERE IS A NARROW AXIS OF INSTABILITY ALONG/AHEAD OF
BOUNDARY...MUCAPES NEARING 1000 J/KG...AND COULD POTENTIALLY SEE A
STRONG STORM OR TWO.
EASTER WEEKEND IS SHAPING UP TO BE DRY AND SEASONAL OVERALL. A
1030MB SURFACE HIGH BUILDS SOUTH BEING THE FRONT AND SETTLES ACROSS
THE CENTRAL PLAINS OVERNIGHT. SFC DPS ARE PROGGED TO DROP TO THE
TEENS IN OUR NW WITH 20S IN THE SOUTHEAST IN THE DRY AIRMASS.
LOOKING LIKE A MUCH COLDER NIGHT THAN WE HAVE HAD RECENTLY HOWEVER
NOT NECESSARILY UNUSUAL FOR THIS TIME OF YEAR WITH NORMAL LOWS IN
THE LOW/MID 30S. FORECAST LOWS ARE IN THE 30S IN GENERAL AND AGREE
PREVIOUS SHIFTS THAT THIS PERIOD WILL NEED TO BE MONITORED FOR
FROST/FREEZE POTENTIAL.
SURFACE RIDGE AXIS SLIPS SOUTHEAST ON SUNDAY WITH RETURN FLOW
SETTING UP DURING THE DAY. ANOTHER COLD FRONT CROSSES THE PLAINS
SUNDAY NIGHT/MONDAY ASSOCIATED WITH UPPER LOW IN ONTARIO AND TROUGH
EXTENDING ACROSS THE UPPER MIDWEST/OHIO VALLEY REGION. BRUNT OF
COLD AIR REMAINS EAST OF THE MISSOURI RIVER...HOWEVER SOME COOLER
AIR DOES BACK INTO OUR NORTHEAST COUNTIES. THIS BEING
SAID...ALTHOUGH HIGHS MAY DROP A DEGREE OR TWO FROM SUNDAY...TEMPS
OVERALL ARE STILL LOOKING SEASONAL OR SLIGHTLY ABOVE.
&&
.PREV DISCUSSION... /ISSUED 1214 AM CDT TUE APR 3 2012/
AVIATION...06Z TAF. THE TAF PERIOD WILL BE MARKED WITH FAIRLY
WINDY CONDITIONS IN RESPONSE TO A TIGHT PRESSURE GRADIENT
FOLLOWING THE PASSAGE OF A COLD FRONT ON MONDAY. NORTHERLY WINDS
WILL AVERAGE 20KTS OR SO AND GUST NEAR 30KTS. WINDS WILL
TRANSITION NORTHEASTERLY TUESDAY AFTERNOON AND ALTHOUGH STILL
BREEZY...WIND SPEEDS WILL GRADUALLY DECREASE AS THE GRADIENT RELAXES.
IT LOOKS LIKE PRECIPITATION WILL HOLD OFF UNTIL BEYOND THE TAF
PERIOD UNTIL THE SOUTHERN PLAINS LOW LIFTS FARTHER NORTH. CLOUD
COVER FOR THE MOST PART SHOULD BE IN THE MVFR CATEGORY ALTHOUGH
SOME IFR CIGS ARE POSSIBLE TUESDAY MORNING.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...PFANNKUCH
LONG TERM/AVIATION...CF
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1214 AM CDT TUE APR 3 2012
.AVIATION...06Z TAF. THE TAF PERIOD WILL BE MARKED WITH FAIRLY
WINDY CONDITIONS IN RESPONSE TO A TIGHT PRESSURE GRADIENT
FOLLOWING THE PASSAGE OF A COLD FRONT ON MONDAY. NORTHERLY WINDS
WILL AVERAGE 20KTS OR SO AND GUST NEAR 30KTS. WINDS WILL
TRANSITION NORTHEASTERLY TUESDAY AFTERNOON AND ALTHOUGH STILL
BREEZY...WIND SPEEDS WILL GRADUALLY DECREASE AS THE GRADIENT RELAXES.
IT LOOKS LIKE PRECIPITATION WILL HOLD OFF UNTIL BEYOND THE TAF
PERIOD UNTIL THE SOUTHERN PLAINS LOW LIFTS FARTHER NORTH. CLOUD
COVER FOR THE MOST PART SHOULD BE IN THE MVFR CATEGORY ALTHOUGH
SOME IFR CIGS ARE POSSIBLE TUESDAY MORNING.
&&
.PREV DISCUSSION... /ISSUED 1100 PM CDT MON APR 2 2012/
UPDATE...UPDATED THE FORECAST TO INCREASE POPS IN THE SOUTHWEST
AND PUT IN SOME DRIZZLE IN THE NORTHEAST. THE NAM AND OBSERVATIONS
TO THE NORTH SUPPORT THIS. INCREASED SKY COVER TO CLOUDY FOR
OVERNIGHT.
PREV DISCUSSION... /ISSUED 346 PM CDT MON APR 2 2012/
SHORT TERM...TONIGHT AND TUESDAY. MAIN FORECAST CONCERN WILL BE
CHANCE FOR SHOWERS AND THUNDERSTORMS.
SURFACE ANALYSIS AND SURFACE OBSERVATIONS INDICATE A COLD FRONT
ACROSS THE EASTERN PART OF THE FORECAST AREA THIS AFTERNOON. AHEAD
OF THE COLD FRONT TEMPERATURES HAVE JUMPED AND ARE QUITE WARM.
COOLER TEMPERATURES ARE BEHIND THE FRONT. SATELLITE SHOWS SOME
STRATUS ACROSS THE FAR NORTHERN PART OF THE FORECAST AREA. THIS WAS
SPREADING FURTHER SOUTH THIS MORNING...BUT HAS HELD OFF DURING THE
AFTERNOON.
WINDS HAVE FINALLY STARTED TO INCREASE TO THE WEST AND WILL CONTINUE
TO INCREASE THIS AFTERNOON FOR THE FAR WEST. WILL LEAVE THE WIND
ADVISORY AS IS.
THE POSITION OF THE FRONT IS KEY THIS AFTERNOON FOR THUNDERSTORM
DEVELOPMENT. MODELS HAVE THUNDERSTORMS DEVELOPING ALONG THE FRONT
DURING THE LATE AFTERNOON AND EARLY EVENING. WITH THE CURRENT
LOCATION OF THE FRONT EXPECT THUNDERSTORMS TO BE IN THE SOUTHEAST
PART OF THE FORECAST AREA. THE HRRR KEEPS THE PRECIPITATION IN THE
FAR SOUTHEAST THROUGH THE EVENING WHILE THE NAM AND GFS HAVE IT A
BIT FURTHER TO THE NORTHWEST. THE BEST MUCAPES ARE IN THE FAR
SOUTHEAST PART OF THE FORECAST AREA WITH THE OVER 1000J/KG CAPES FAR
IN THE SOUTHEASTERN PART OF THE FORECAST AREA.
LATER THIS EVENING AND OVERNIGHT AN UPPER LEVEL LOW DEVELOPING ON
THE SOUTHERN HIGH PLAINS STARTS TO DRIFT TO THE NORTH AND PUSHES
PRECIPITATION TO THE NORTH BEHIND THE FRONT. MOST OF THE
PRECIPITATION SHOULD BE IN THE SOUTHERN PART OF THE FORECAST AREA.
THE UPPER LEVEL LOW CONTINUES TO DRIFT THROUGH THE SOUTHERN HIGH
PLAINS ON TUESDAY AND THE CHANCE FOR SHOWERS CONTINUES MAINLY IN THE
SOUTH/SOUTHWEST.
LONG TERM...TUESDAY NIGHT THROUGH MONDAY. PRIMARY FORECAST CONCERN LIES WITH
PRECIPITATION CHANCES EARLY ON IN THE PERIOD.
LOOKING AT THE TIME FRAME STARTING TUESDAY NIGHT AND CONTINUING
THROUGH WEDNESDAY NIGHT...THE MAIN STORY LIES WITH THE IMPACT ACROSS
THE REGION FROM A PASSING UPPER LEVEL LOW PRESSURE SYSTEM AND
ASSOCIATED PRECIPITATION CHANCES. LATEST MODELS RUNS ARE IN PRETTY
GOOD AGREEMENT AT THE START OF THE PERIOD...SHOWING THE LOW CENTERED
OVER THE PANHANDLES OF TX/OK...BUT MORE VARIANCES START TO SHOW UP
THROUGH THE OVERNIGHT HOURS AND INTO WEDNESDAY. THE SYSTEM DOESNT
MAKE A WHOLE LOT OF EASTWARD PROGRESS...WITH A RIDGE AXIS TO THE
EAST EXTENDING FROM THE GULF COAST REGION UP INTO THE ERN
DAKOTAS...AND BY WEDNESDAY EVENING LOOKS TO RANGE IN LOCATION FROM
SC KS TO WRN OK. INCREASED LIFT OUT AHEAD OF THE LOW PRESSURE
SYSTEM WILL HELP WITH THE NORTHWARD SPREAD OF PRECIPITATION FROM THE
SRN PLAINS INTO THE CWA TUESDAY EVENING/OVERNIGHT...WHICH WILL
CONTINUE ON INTO THE DAYTIME HOURS ON WEDNESDAY AS INCREASED LOW/MID
LEVEL FRONTOGENETICAL ON THE NORTHERN SIDE OF THE LOW SHIFTS INTO
THE CWA. DECIDED TO INSERT A MENTION OF ISOLATED THUNDER WED
EVENING...WITH SOME OF THE MODELS/SREF PROBS SHOWING THE POTENTIAL
LINGERING AROUND THE SOUTHEASTERN CORNER OF THE CWA. EXPECTING
PLENTY OF CLOUD COVER AND GENERALLY N/NE WINDS AS THE MAIN SFC LOW
SLIDES TO THE SOUTH OF THE CWA...WITH HIGHS TOPPING OUT IN THE
LOW/MID 50S. MODELS ARE A LITTLE SLOWER THURSDAY EVENING/NIGHT
PUSHING PRECIPITATION CHANCES EAST OF THE CWA AS THE UPPER LEVEL LOW
MAKES ITS WAY TOWARD THE MO RIVER...AND PUSHED POPS BACK WEST TO
INCLUDE ALL COUNTIES.
UPPER LEVEL SHORTWAVE RIDGING BUILDING INTO THE PLAINS IN THE WAKE
OF THIS LATEST SYSTEM IS EXPECTED TO KEEP THURSDAY AND THURSDAY
NIGHT DRY. SEE A SLIGHT BUMP IN HIGHS BUT TEMPS REMAIN ON THE
RELATIVELY COOL SIDE /COMPARED TO THE LAST FEW DAYS...BUT STILL NEAR
OR ABOVE AVG/...WITH THE CWA REMAINING ON THE WRN/SRN FRINGE OF SFC
HIGH PRESSURE OVER THE WRN GREAT LAKES...AND AM EXPECTING LOWER 60S.
NEXT CHANCE FOR PRECIPITATION IS EXPECTED TO COME TO WESTERN
PORTIONS OF THE CWA DURING THE DAY ON FRIDAY AND EXPAND FURTHER EAST
FRIDAY NIGHT...AS ANOTHER SHORTWAVE TROUGH AXIS LOOKS TO SWING
THROUGH THE NORTHERN/CENTRAL PLAINS. MODELS VARY SOME THROUGH THIS
TIMEFRAME...WITH THE GFS SHOWING THIS ENERGY ASSOCIATED WITH AN
ELONGATED LOW OVER WRN/CENTRAL CANADA...WHILE THE EC SHOWS ANY LOW
LOCATED OFF THE PAC NW COAST. KEPT THE HIGHER POPS ACROSS THE NORTH
WHERE THERE IS BETTER AGREEMENT BETWEEN THE MODELS...BUT POPS GO ALL
THE WAY SOUTH TROUGH THE CWA WITH THE GFS CONTINUING TO SHOW MORE
COVERAGE. THE MAIN INSTABILITY AXIS LOOKS TO SET UP JUST WEST OF
THE CWA DURING THE DAY...AND PUSH THROUGH DURING THE OVERNIGHT
HOURS...WITH MUCAPE VALUES UPWARDS OF 7-800 J/KG...SO THREAT OF SOME
STRONG STORMS WILL REMAIN...BUT WILL CONTINUE TO KEEP AN EYE ON THE
POTENTIAL FOR SEVERE STORMS.
KEPT THE FORECAST FOR THE UPCOMING WEEKEND AND INTO MONDAY
DRY...THOUGH THE GFS TRIES TO LINGER SOME POPS IN THE EAST EARLY ON
SAT MORNING. AN ACCOMPANYING SURFACE COLD FRONT IS EXPECTED TO BE ON
ITS WAY THROUGH THE CWA SATURDAY MORNING...BUT MODELS DO VARY SOME
ON THE TIMING. EC IS ON THE QUICKER SIDE...WITH THE FRONT CLEARING
THE CWA SAT MORNING...WHILE THE GFS WOULD BE MORE INTO THE
AFTERNOON. LOOKS TO BE BREEZY DAY ON SATURDAY...WITH NORTHWEST
WINDS PICKING UP BEHIND THE FRONT. MORE ZONAL/NORTHWESTERLY FLOW
SETS UP IN THE UPPER LEVELS FOR SUN/MON WITH A RIDGE SET UP OVER THE
SRN/SWRN CONUS...WITH NO NOTABLE SYSTEM LOOKING TO PASS THROUGH.
BEHIND THE SFC FRONT...HIGH PRESSURE BUILDS IN AND IS THE DOMINANT
FEATURE ON SUNDAY...BRINGING A PLEASANT WITH LIGHT WINDS AND HIGHS
TOPPING OUT IN THE LOWER/MID 60S. MONDAY COULD SEE AN INCREASE IN
WINDS DEPENDING ON THE MODEL...BUT STILL EXPECTING ANOTHER NICE DAY
WITH HIGHS SIMILAR TO SUNDAY.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1150 PM CDT MON APR 2 2012
.AVIATION...
06Z TAFS FOR KOMA...KLNK...AND KOFK.
MVFR CIGS HAVE REACHED KOFK AND KLNK...AND SHOULD REACH KOMA
BETWEEN 06-08Z. KEPT KOFK CIGS JUST ON THE LOW END OF
MVFR...THOUGH WOULD NOT BE SURPRISED BY A DIP INTO HIGHER-END IFR
OVERNIGHT. MVFR CIGS SHOULD LAST THROUGH AROUND MIDDAY...BEFORE
LIFTING INTO VFR RANGE...BUT ALL SITES SHOULD KEEP AT LEAST VFR
CIGS THROUGH MUCH OF THE TAF PERIOD. GUSTY NORTHWEST WINDS WILL
VEER TO NORTHEASTERLY THROUGH THE DAY...REMAINING GUSTY THROUGH
THE TAF CYCLE.
MAYES
&&
.PREV DISCUSSION... /ISSUED 927 PM CDT MON APR 2 2012/
DISCUSSION...
UPDATED THE FORECAST FOR SKY...POP/WEATHER...AND TEMPERATURE
TRENDS THIS EVENING. OVERCAST STRATUS DECK HAS ENCROACHED INTO
NORTHWEST CWA...AND RUC/NAM/HRRR PROGS INDICATE IT WILL OVERSPREAD
MUCH OF EASTERN NEB INTO WESTERN IA THROUGH THE EVENING AND
OVERNIGHT HOURS...WITH CLOUDS LINGERING THROUGH MUCH OR ALL OF
TOMORROW AS WELL. HAVE BUMPED CLOUDS TO OVERCAST/CLOUDY COVERAGE
THROUGH AT LEAST MIDDAY TOMORROW.
PRECIP HAS REMAINED MAINLY SOUTH AND WEST OF THE CWA...WITH JUST A
FEW SHOWERS POPPING UP ALONG AND BEHIND THE FRONT. HAVE UPDATED
THE FORECAST TO MENTION JUST ISOLATED SHOWERS FOR THE NEXT HOUR OR
SO...WITH NO MEASURABLE PRECIP FOR THE REST OF THE NIGHT. ALSO
REMOVED MEASURABLE PRECIP FROM THE NORTHWEST CWA AND ADDED
DRIZZLE...AS KLBF RADAR HAS A DRIZZLE APPEARANCE WITH LIGHT PRECIP
ON THE KONL OB.
FINALLY...WITH TEMPERATURES DROPPING ABRUPTLY BEHIND THE
FRONT...HAVE UPDATED THE TEMPERATURE TREND FOR A SHARP DROPOFF
IMMEDIATELY BEHIND THE FRONT...WITH A SLOWER DROPOFF THROUGH THE
REST OF THE NIGHT AS CLOUDS INCREASE AND GUSTY WINDS CONTINUE.
MAYES
PREV DISCUSSION... /ISSUED 336 PM CDT MON APR 2 2012/
DISCUSSION...
THE SHORT TERM CONCERNS WILL BE THE POTENTIAL FOR THUNDERSTORMS
AND SEVERE WEATHER AND IF A WIND ADVISORY WILL BE NEEDED.
AT 20Z...THE COLD FRONT HAD FINALLY MADE IT INTO NORFOLK AND THEIR
TEMPERATURES WERE BEGINNING TO FALL. AHEAD OF THE
FRONT...TEMPERATURES TOPPED OUT IN THE 80S TO LOWER 90S. THE LOW
CLOUDS HAD MADE IT INTO THE THE ONEILL AREA AND TEMPERATURES WERE
ONLY IN THE 50S. WINDS IN THE WEST CENTRAL PART OF NEBRASKA WERE
QUITE STRONG WITH GUSTS IN THE 40 TO 50 MPH IN SPOTS.
TONIGHT...THE SURFACE COLD FRONT WILL BE MOVING ACROSS THE REST OF
EASTERN NEBRASKA AND SOUTHWEST IOWA. THE HIGHER UPPER 50S AND
LOWER 60S DEGREE DEWPOINTS AT 20Z EXTENDED FROM BEATRICE TO OMAHA
AND THESE WILL SHIFT EASTWARD WITH TIME. THE 4KM WRF HAD
THUNDERSTORMS ALONG THE FRONT...WHILE THE 18Z NAM WAS DRY...THE
LATEST RUC HAD SOME STORMS DEVELOPING TOWARD FAIRBURY AND THE GFS
HAD AN AREA SIMILAR TO THE 4KM WRF...BUT SHIFTED FARTHER SOUTHEAST
AND MAINLY ALONG AND SOUTH OF I80. THERE IS THE POTENTIAL
FOR THUNDERSTORMS THIS EVENING AHEAD OF AND ALONG THE FRONT AND
WILL MAINTAIN ISOLATED TO SCATTERED THUNDERSTORM CHANCES MAINLY
ALONG AND SOUTH OF I80. THE ATMOSPHERE HAS GOOD INSTABILITY AND
STEEP LAPSE RATES TO WORK WITH...HOWEVER THE SHEAR PARAMETERS DO
NOT APPEAR AS FAVORABLE IN THIS AREA. SPC HAS A SLIGHT RISK AND
THE SLIGHT RISK APPEARS WARRANTED BASED ON CONDITIONAL FACTORS AS
SHOULD THUNDERSTORMS GET GOING THEY COULD CONTAIN SOME HAIL AND
DAMAGING WINDS. BEHIND THE FRONT...ESPECIALLY ACROSS NORTHEAST
NEBRASKA THE WINDS WILL BE STRONG. AT THIS TIME WILL HAVE WINDY
CONDITIONS AT 20 TO 30 MPH WITH GUSTS TO 45...BUT HAVE NOT GONE
WITH A WIND ADVISORY AT THIS TIME. BEHIND THE FRONT...WITH THE LOW
CLOUDS THERE MAY BE SOME SHOWERS IN NORTHEAST NEBRASKA AND SOME OF
THESE MAY LINGER INTO TUESDAY.
THE SOUTHERN ENERGY WITH THIS STORM SYSTEM WILL CLOSE OFF AND LIFT
NORTH. THIS WILL RETURN THE CHANCE FOR SHOWERS AND THUNDERSTORMS
TUESDAY NIGHT AND WEDNESDAY AND WEDNESDAY NIGHT AND THEN MOVE OUT
THURSDAY.
THURSDAY NIGHT THROUGH MONDAY....THE STORM SYSTEM THAT WILL
AFFECT US FOR MUCH OF THE WEEK WILL BE OVER SOUTHERN MISSOURI AT
THE START OF THE EXTENDED WITH DRY CONDITIONS...SOUTHEAST BREEZES
AND COMFORTABLE TEMPERATURES IN THE 60S FRIDAY. FRIDAY NIGHT...THE
TROF OVER THE PACIFIC NORTHWEST WILL PUSH FAR ENOUGH EASTWARD TO
PUSH TO FRONT INTO PARTS OF EASTERN NEBRASKA BY 12Z SATURDAY.
SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE AHEAD OF AND ALONG THE
COLD FRONT FRIDAY NIGHT AND SATURDAY. AS THIS SYSTEM MOVES OUT OF
THE AREA...MID LEVEL RIDGING BUILDS IN AND DRY WEATHER AND MORE
SEASONABLE WEATHER IS FORECAST FOR SATURDAY AND SUNDAY.
ZAPOTOCNY
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
99/99
AREA FORECAST DISCUSSION
NWS BUFFALO NY
635 PM EDT TUE APR 3 2012
.SYNOPSIS...
AN AREA OF LOW PRESSURE WILL PASS SOUTH OF NEW YORK STATE TONIGHT
AND MAY BRING A FEW ISOLATED SHOWERS TO PARTS OF WESTERN NEW YORK.
ARCTIC HIGH PRESSURE WILL BUILD SOUTH ACROSS THE REGION WEDNESDAY
WITH COOLER TEMPERATURES AND FAIR WEATHER RETURNING FOR THE REST
OF THE WEEK.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
A WEAK SURFACE LOW ACROSS ILLINOIS WILL TRACK ACROSS KENTUCKY
OVERNIGHT. AN ASSOCIATED WARM FRONT EXTENDS TO THE ENE OF THE
LOW...TOWARD WESTERN NEW YORK. WITH VERY DRY AIR IN PLACE BENEATH
700 MB...EXPECT MOST LOCATIONS TO LARGELY REMAIN DRY OVERNIGHT.
HOWEVER...RADAR DOES SHOW SOME SHOWERS ACROSS SOUTHERN ONTARIO
FROM PORT HURON TO LONDON...WITH WHATEVER DOES HOLD TOGETHER WITH
THIS LIKELY TO CLIP WESTERN PORTIONS OF THE SOUTHERN TIER THIS
EVENING. THE HRRR IS LATE...BUT APPEARS TO CAPTURE THIS
EVENTUALLY...WITH THE GFS/RGEM/NAM HINTING AT THIS IN THE RH
FIELDS MORE SO THAN THE QPF. BASED ON THE TRAJECTORY OF THE
SHOWERS...WILL MAINTAIN CHANCE POPS IN SOUTHERNMOST PORTIONS OF
THE CWA...WHILE TRIMMING THINGS BACK TO THE NORTH.
MOSTLY CLOUDY SKIES THE FIRST HALF OF THE NIGHT WILL KEEP AREA
TEMPERATURES QUITE A BIT WARMER TONIGHT THAN TUESDAY MORNINGS SUB-
FREEZING READINGS. UPPER 30S FOR WESTERN NY AND THE FINGER LAKES
AND LOW TO MID 30S FOR THE NORTH COUNTRY. SKIES SHOULD CLEAR FROM
NW-SE LATE TONIGHT.
ARCTIC HIGH PRESSURE WILL BUILD ACROSS THE REGION WEDNESDAY BEHIND
THE DEPARTING LOW. 850MB TEMPS WEDNESDAY WILL DROP TO AROUND -3C
WHICH WILL SUPPORT HIGH TEMPS ONLY REACHING INTO THE LOW 50S ACROSS
WESTERN NY DESPITE MAINLY CLEAR SKIES. MORE CLOUDS OVER THE NORTH
COUNTRY AND 850MB TEMPS CLOSER TO -4C/-5C WILL KEEP HIGH TEMPS
LIMITED TO THE UPPER 40S/LOW 50S. WINDS WEDNESDAY WILL BECOME BREEZY
IN THE AFTERNOON AS THE PRESSURE GRADIENT TIGHTENS WITH THE
APPROACHING ARCTIC HIGH AND THE SURFACE LOW OVER THE MID-ATLANTIC
COAST. NORTHWEST GUSTS MAY APPROACH 20 TO 25 MPH ACROSS THE NORTH
COUNTRY AND SOUTHEAST OF THE LAKE.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
IT WILL BE SEASONABLY CHILLY DURING THIS PERIOD AS OUR REGION WILL
REMAIN IN THE COLD SIDE OF A WEAKLY ESTABLISHED REX BLOCK. THIS
LONGWAVE PATTERN WILL FEATURE A CUT OFF LOW OVER THE PLAINS THAT
WILL BE TOPPED BY A HIGH AMPLITUDE RIDGE THAT WILL EXTEND NORTHWARDS
PAST HUDSON BAY. WHILE THE UNDERLYING CUT OFF IS FORECAST TO
PROGRESS EASTWARD ACROSS THE SOUTHERN STATES DURING THIS TIME
FRAME...THE RIDGE WILL BE MUCH SLOWER IN ITS PROGRESSION ACROSS THE
GREAT LAKES REGION.
DOWNSTREAM FROM THE AFOREMENTIONED RIDGE WILL BE A FAIRLY SHARP
TROUGH THAT WILL BE CENTERED OVER QUEBEC AND NEW ENGLAND. THIS WILL
HOLD OUR TEMPERATURES AT OR SLIGHTLY BELOW NORMAL FOR THIS PERIOD...
WHILE AN EXPANSIVE SFC HIGH WILL KEEP THE VAST MAJORITY OF THE
REGION PRECIPITATION FREE. ALL IN ALL...A PRETTY `VANILLA` PERIOD.
A ROBUST SHORTWAVE WILL DROP INTO THE BASE OF THE EASTERN CANADIAN
TROUGH WEDNESDAY NIGHT...AND AS THIS BUNDLE OF ENERGY CROSSES THE
NORTH COUNTRY...THERE MAY BE ENOUGH LOW LEVEL MOISTURE AND LIFT
PRESENT TO POSSIBLY GENERATE A COUPLE WIDELY SEPARATED RAIN OR WET
SNOW SHOWERS. WILL USE LOW CHC POPS TO COVER THIS MINIMAL
POSSIBILITY. THE REMAINDER OF THE FORECAST AREA WILL BE PCPN
FREE...BUT WITH ANOTHER FROST OR FREEZE. H85 TEMPS OF -8C WILL HELP
TO PUSH OVERNIGHT LOWS BACK DOWN INTO THE 20S AND LOWER 30S.
A MASSIVE AREA OF HIGH PRESSURE WILL EASE SOUTHWARDS ACROSS THE
UPPER GREAT LAKES ON THURSDAY. THIS WILL PROVIDE OUR FORECAST AREA
WITH PARTLY/MSTLY SUNNY SKIES...ALTHOUGH WITH H85 TEMPS STILL COLDER
THAN -4C AND SOME RESIDUAL LOW LEVEL MOISTURE IN PLACE...SITES AWAY
FROM THE LAKES MAY EXPERIENCE A FEW HOURS OF BROKEN STRATO-CU CLOUD
COVER. IT WILL BE A COOL DAY AS WELL WITH MAX TEMPS STRUGGLING TO
REACH NORMAL EARLY APRIL VALUES.
AS THE LARGE SFC HIGH SETTLES OVER THE ENTIRE GREAT LAKES REGION
THURSDAY NIGHT...THE PRESSURE GRADIENT WILL WEAKEN SO THAT VERY GOOD
RADIATIONAL COOLING WILL BECOME ESTABLISHED UNDER CLEAR SKIES. THIS
WILL SET THE STAGE FOR YET ANOTHER WIDESPREAD FREEZE AWAY FROM THE
LAKES. OVERNIGHT LOWS WILL RANGE FROM THE FREEZING MARK NEAR THE
LAKE SHORES TO 20 TO 25 IN THE SRN TIER VALLEYS AND EAST OF LAKE
ONTARIO.
FOR FRIDAY AND FRIDAY NIGHT...A H5 RIDGE WILL SLOWLY PUSH ACROSS THE
UPPER GREAT LAKES WHILE THE CORE OF THE SFC HIGH WILL DRIFT TO BE
ABOUT LAKE ERIE. THIS WILL PROVIDE OUR FORECAST AREA WITH NEARLY
CLOUD FREE SKIES AND SEASONABLE TEMPERATURES. THAT WILL INCLUDE
ANOTHER FROSTY NIGHT FRIDAY NIGHT...ESPECIALLY FOR THE SITES WELL
AWAY FROM THE LAKES.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
FAIR...SEASONABLY MILD WEATHER AT THE START OF THIS PERIOD WILL
GIVE WAY TO CHILLY UNSETTLED CONDITIONS AS TROUGHINESS OVER THE
HIGH PLAINS OF SASKATCHEWAN WILL DIG SOUTHEAST ACROSS THE GREAT
LAKES REGION. THIS FEATURE WILL EVENTUALLY CARVE ITS WAY INTO A
LONGWAVE TROUGH OVER THE EASTERN HALF OF NORTH AMERICA. AS A
RESULT... TEMPERATURES WILL DEFINITELY TREND DOWNWARDS DURING THIS
PERIOD WITH BELOW NORMAL MERCURY READINGS BECOMING ESTABLISHED BY
TUESDAY. THESE VALUES WILL LIKELY PERSIST THROUGH AT LEAST MID
WEEK.
SATURDAY WILL BE THE NICEST DAY OF THIS PERIOD...BY FAR...AS STRONG
HIGH PRESSURE WILL DRIFT ACROSS OUR FORECAST AREA. SUN FILLED SKIES
WILL BOOST SFC TEMPS INTO THE UPPER 50S TO LOWER 60S FOR MOST AREAS
WITH EVEN WARMER CONDITIONS EXPECTED IN THE GENESEE VALLEY.
AS THE HIGH MOVES OFF THE EAST COAST SUNDAY NIGHT...A PACIFIC BASED
COLD FRONT WILL PUSH ACROSS THE UPPER GREAT LAKES AND MID WEST. THIS
FRONT WILL MOVE ACROSS OUR AREA ON SUNDAY...AND WHILE THE VAST
MAJORITY OF THE DAY SHOULD BE RAIN FREE...THERE WILL PROBABLY BE A 3
HOUR WINDOW OF SCT SHOWER ACTIVITY.
SHORTWAVE RIDGING IN THE WAKE OF THE FRONT SHOULD PROVIDE US WITH
DRY WEATHER SUNDAY NIGHT...BUT ADDITIONAL ENERGY FEEDING INTO THE
TROUGH WILL ENCOURAGE THE SYSTEM TO DIG ITS WAY ACROSS LOWER
ONTARIO. FALLING HGTS AND COLD ADVECTION FROM THIS PROCESS COULD
SUPPORT SOME MORE SHOWERS...MAINLY IN THE AFTERNOON AND MONDAY
NIGHT.
ON TUESDAY...A DEEP LONGWAVE TROUGH WILL BE ANCHORED IN THE VCNTY OF
NEW YORK STATE. THIS WILL KEEP COOL UNSETTLED WEATHER OVER OUR
REGION WITH HIGH TEMPERATURES NOT MAKING IT OUT OF THE 40S.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
VFR CONDITIONS CONTINUE ACROSS THE ENTIRE AREA TODAY UNDER SCT CLOUD
COVER. A WEAK SURFACE LOW WILL SHIFT SOUTH OF NEW YORK STATE TONIGHT
WITH SKIES BECOMING OVERCAST BUT REMAINING VFR. A SLIGHT CHANCE OF
ISOLATED RAIN SHOWERS IS POSSIBLE AS THE LOW SHIFTS EAST BUT
CONFIDENCE IS TOO LOW TO INCLUDE IN TAFS OTHER THAN KJHW.
ARCTIC HIGH PRESSURE WILL BUILD SOUTH WEDNESDAY AND SKIES WILL CLEAR
EARLY WEDNESDAY WITH SOME SCATTERED DIURNAL CLOUDS RETURNING IN THE
AFTERNOON. WINDS WILL INCREASE IN THE AFTERNOON WITH SOME GUSTS
POSSIBLE TO 20 OR 25 KTS.
OUTLOOK...
WEDNESDAY NIGHT...MAINLY VFR.
THURSDAY AND FRIDAY...VFR.
SATURDAY...VFR.
&&
.MARINE...
A WEAK LOW WILL PASS JUST SOUTH OF NEW YORK STATE TONIGHT THEN
SETTLE OFF THE EAST COAST BY WEDNESDAY MORNING WITH NO IMPACT TO
WIND AND WAVE CONDITIONS ACROSS THE LAKES. A MODEST NORTH TO
NORTHWEST FLOW OF COLDER AIR WILL SET UP ACROSS THE LAKES WEDNESDAY
AND THURSDAY AS ARCTIC HIGH PRESSURE BUILDS SOUTH ACROSS NY. THE
RESULTING WINDS AND WAVES MAY APPROACH SMALL CRAFT ADVISORY LEVELS
ALONG THE EAST AND SOUTH SHORES OF LAKE ONTARIO IN THE AFTERNOON.
&&
.CLIMATE...
THE MONTHLY CLM CLIMATE SUMMARIES HAVE BEEN UPDATED TO INCLUDE THE
NARRATIVE SECTION AT THE BOTTOM. THEY ARE AVAILABLE ON OUR WEBSITE
UNDER THE CLIMATE SECTION. HERE ARE SOME TIDBITS BELOW...
MARCH 2012 IS A MONTH FOR THE RECORD BOOKS AS AN UNSEASONABLE AND
PERSISTENT WARM PATTERN REMAINED ACROSS THE EASTERN US. FOR BUFFALO
MARCH FINISHED WITH AN AVERAGE TEMPERATURE OF 47.4 DEGREES WHICH IS
+13.4 DEGREES ABOVE NORMAL...AND 2.9 DEGREES WARMER THAN THE
PREVIOUS WARMEST MARCH. THIS 2.9 DEGREES IS THE LARGEST SEPARATION
BETWEEN WARMEST...AND 2ND WARMEST FOR ANY MONTH IN BUFFALO...WITH
THE NOW SECOND LARGEST SEPARATION 2.6 DEGREES FOR THE TWO WARMEST
MONTHS OF SEPTEMBER.
FOR ROCHESTER MARCH FINISHED WITH AN AVERAGE TEMPERATURE OF 47.3
DEGREES WHICH IS +13.0 DEGREES ABOVE NORMAL...AND 3.5 DEGREES WARMER
THAN THE PREVIOUS WARMEST MARCH. THIS 3.5 DEGREES IS THE LARGEST
SEPARATION BETWEEN WARMEST...AND 2ND WARMEST FOR ANY MONTH IN
ROCHESTER WITH THE NOW SECOND LARGEST SEPARATION 3.1 DEGREES FOR THE
TWO WARMEST MONTHS OF SEPTEMBER.
FOR BOTH CITIES MARCH FINISHED WARMER THAN THE NORMAL APRIL. THE
47.4 DEGREES AVERAGE MARCH 2012 TEMPERATURE IN BUFFALO WAS 1.5
DEGREES WARMER THAN THE NORMAL APRIL VALUE. FOR ROCHESTER THE 47.3
DEGREES AVERAGE MARCH 2012 TEMPERATURE WAS 1.0 DEGREES WARMER THAN
THE NORMAL APRIL VALUE.
BUFFALO ESTABLISHED SEVEN NEW RECORD HIGH TEMPERATURES IN MARCH
2012...WHILE ROCHESTER ESTABLISHED THREE NEW RECORD HIGH
TEMPERATURES. BOTH CITIES SET 5 NEW RECORD WARM MINIMUM
TEMPERATURES.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...SMITH
NEAR TERM...APFFEL/SMITH
SHORT TERM...RSH
LONG TERM...RSH
AVIATION...APFFEL/SMITH
MARINE...SMITH
CLIMATE...THOMAS/HITCHCOCK
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
759 PM EDT WED APR 4 2012
.SYNOPSIS...
A WEAK UPPER LEVEL DISTURBANCE WILL TOUCH OF SCATTERED THUNDERSTORMS
THIS EVENING INTO TONIGHT. A COLD FRONT WILL MOVE SOUTH ACROSS THE
REGION ON THURSDAY. AS LOW PRESSURE DEVELOPS OFFSHORE RAIN WILL
SPREAD BACK NORTH ACROSS THE CAROLINAS LATE THURSDAY INTO EARLY
FRIDAY. THE RAIN WILL BE MODERATE TO HEAVY LATE THURSDAY NIGHT.
BRISK AND COOLER CONDITIONS FOLLOW THIS SYSTEM FRIDAY AND INTO THE
WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 755 PM WEDNESDAY...CONVECTION NOT AS WIDESPREAD ACROSS THE FA
AS RECENTLY PROGGED BY MODELS FOR THIS TIME PERIOD. AS A
RESULT...HAVE CUT DOWN POPS AND AREAL COVERAGE OF PCPN FOR THE
REMAINDER OF THE EVENING. PLENTY OF MESOSCALE BOUNDARY FEATURES TO
AID IN FIRING UP CONVECTION. IE. RADAR ID OF THE SEA BREEZE MOVING
INLAND...ALTHOUGH NOT AS PRONOUNCED AS EARLIER...STILL AN AID FOR
FIRING CONVECTION. OUTFLOW FROM THE MORE ORGANIZED CONVECTION NORTH
OF THE ILM CWA...WILL ALSO BE DROPPING SOUTH INTO THE ILM CWA DURING
THIS EVENING. LATEST HRRR MODEL RUN INDICATES THE INTERACTION OF THE
OUTFLOW AND SEA BREEZE DURING MID TO LATE THIS EVENING FOR CONTINUED
CONVECTION DEVELOPMENT...PRIMARILY OVER THE ILM NC CWA. CONVECTION
WILL REMAIN LESS ORGANIZED ACROSS THE ILM SC CWA. MODIFIED OVERNIGHT
DEWPOINTS AND INCREASED THEM SLIGHTLY BASED ON LATEST OBSERVATIONS
AND 18Z NAM TRENDS. ALSO...MIN TEMPS WERE UPPED BY 1 TO 3 DEGREES
DUE TO THESE HIER DEWPOINTS AND ALSO THE SLOWER SOUTHWARD
PROGRESSION OF THE COLD FRONT...VIA LATEST SFC ANALYSIS AND SLOWER
SOUTHWARD PUSH OF THE COOLER AIR VIA 1K-8H PARTIAL THICKNESS
PACKING. WILL CONTINUE TO MENTION GUSTY WINDS AND SMALL HAIL
ACCOMPANYING ANY OF THE CONVECTION THROUGH MIDNIGHT.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 PM WEDNESDAY...FAIRLY ACTIVE WEATHER EXPECTED DURING THE
SHORT TERM. A BACKDOOR COLD FRONT WILL ALREADY HAVE MADE SOME
SOUTHWARD PROGRESS ACROSS THE REGION BY THURSDAY MORNING. RAINFALL
CHANCES WILL BE QUITE LOW WITH ITS PASSAGE AND ITS WEST-EAST
ORIENTATION WILL LEAD TO A NORTH-SOUTH GRADIENT IN AFTERNOON HIGH
TEMPERATURES. FALLING PRESSURES BOTH SURFACE AND ALOFT COMING IN
FROM THE SOUTHWEST LATER IN THE DAY HOWEVER WILL VERY QUICKLY
GENERATE ISENTROPIC UPGLIDE CALLING FOR A PRONOUNCED INCREASE IN
POPS AS LIGHT TO MODERATE RAIN BREAKS OUT SOUTH TO NORTH ACROSS
THE CAROLINAS. STRONGEST MID LEVEL PVA OCCURS IN THE 06-12Z FRIDAY
TIME FRAME GENERATING FLAT WAVE OF LOW PRESSURE OFF THE COAST ALONG
THE BOUNDARY. IT IS DURING THIS TIME FRAME THAT RAINFALL WILL GROW
HEAVIEST AND SHOULD NET US MOST OF THE APPROX 1 INCH EXPECTED
AREA-WIDE. SOME DEVIATION BOTH ABOVE AND BELOW THAT NUMBER APPEAR
POSSIBLE ESPECIALLY IF SOME WEAK FGEN BANDING DEVELOPS. ASSUMING
THE PREFERRED WRF SOLUTION VERIFIES BEST SOME STRONG COLD AND DRY
ADVECTION WILL BE UNDERWAY BEHIND THE EXITING COASTAL LOW AS
FRIDAY PROGRESSES. FRIDAY WILL BE A RATHER BRISK AND COOL DAY WITH
HIGHS THAT STRUGGLE TO EXCEED 60 EXCEPT FOR FAR SRN ZONES WHERE
MID 60S APPEAR ACHIEVABLE. N WINDS 10 TO 15 MPH GUSTING TO 25 MPH
OR MORE WILL KEEP THE APPARENT TEMPS IN THE 50S FOR MUCH OF THE
AFTERNOON. FRIDAY NIGHT WILL GROW QUITE CHILLY BUT A CONTINUED
ALBEIT ABATING NORTHERLY WIND WILL PRECLUDE RADIATIONAL COOLING.
LOWERED FORECAST NUMBERS A FEW DEG AND GENERALLY SHOW VALUES CLOSE
TO 40. THE COOLER MET NUMBERS WOULD IMPLY SOME FROST CONCERNS OVER
INLAND ZONES.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 3 PM WEDNESDAY...SLOW MOVING 5H CUTOFF SOUTHEAST OF NEW
ENGLAND WILL KEEP DEEP NORTHWEST FLOW IN PLACE INTO MON. THE 5H
LOW STARTS TO LIFT NORTH EARLY MON...SHIFTING THE UPPER PATTERN
OVER THE SOUTHEAST MON NIGHT/TUE. WEAK COLD FRONT CROSSES THE AREA
MON MORNING AS THE UPPER LOW LIFTS OUT. FRONT IS MOISTURE STARVED
AND MAY PASS UNNOTICED OR AS A SLIGHT INCREASE IN CLOUD COVER.
FLOW ALOFT BECOMES MORE WESTERLY MON NIGHT THEN BRIEFLY SOUTHWEST
AHEAD OF HIGHLY AMPLIFIED 5H TROUGH TUE/TUE NIGHT. CANNOT RULE OUT
A FEW SHOWERS AHEAD OF A STRONG COLD FRONT LATER TUE...THOUGH
MOISTURE RETURN AHEAD OF THE FRONT IS LESS THAN IMPRESSIVE. WILL
CARRY A SILENT POP TUE BUT THIS MAY BE A LITTLE GENEROUS GIVEN THE
LATEST GUIDANCE.
MOST SIGNIFICANT ASPECT OF THE FORECAST IS AT THE END OF THE PERIOD
WHEN STRONG COLD ADVECTION FOLLOWING THE TUE COLD FRONT SETS UP.
STILL UNCERTAINTY AS TO THE THE STRENGTH OF THE COLD ADVECTION...BUT
THICKNESS VALUES AND 850 TEMPS WOULD SUGGEST HIGHS FOR WED IN THE
UPPER 50S AND LOWS IN THE MID 30S. EXTENDED MOS IS HIGHER...AS WOULD
BE EXPECTED GIVEN THE LARGE CLIMO INFLUENCE. SEVERAL FACTORS MAKE
THE TEMP FORECAST FOR THE MIDDLE OF NEXT WEEK TRICKY. HOW MUCH WILL
THIS AIR MASS MODIFY AS IT DROPS SOUTH OUT OF CANADA EARLY NEXT
WEEK...ESPECIALLY GIVEN THE WARM SPRING AND THE ABOVE NORMAL SOIL
TEMPS ACROSS MUCH OF THE EASTERN US. HOW WILL TREES THAT HAVE
STARTED TO LEAF OUT IMPACT THE AIR MASS. HAVE LOWERED TEMPS A FEW
DEGREES LATE IN THE PERIOD BUT FURTHER CHANGES WILL LIKELY BE
REQUIRED.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
AS OF 00Z...A LINE OF SHOWERS AND ISOLATED THUNDERSTORMS WITH AN
ASSOCIATED GUST FRONT IS MOVING SOUTHEAST THIS EVENING TOWARDS THE
ILM/LBT TERMINALS. THIS ACTIVITY IS OCCURRING WELL AHEAD OF A COLD
FRONT AND IS SHOWING SIGNS OF WEAKENING. OTHER WIDELY SCATTERED
CONVECTION IS WEST OF THE FLO/LBT TERMINALS MOVING EAST.
BECAUSE ACTIVITY IS MORE ISOLATED HAVE ONLY INDICATED TEMPO SHOWERS
AT FLO/CRE/MYR THIS EVENING. BECAUSE OF THE OUTFLOW DROPPING SOUTH
WILL INDICATE SHOWERS/VCTS AT LBT/ILM THIS EVENING. THEN AFTER
06Z AS THE OUTFLOW DROPS FURTHER SOUTH THINK THE CHANCES FOR
SHOWERS/VCTS WILL INCREASE AT THE FLO/MYR/CRE TERMINALS AND
DECREASE AT THE ILM/LBT TERMINALS. ALL PRECIPITATION SHOULD END BY
SUNRISE. AS THE PRECIPITATION ENDS WINDS WILL BECOME LIGHT WEST TO
NORTHWEST. PATCHY FOG SHOULD DEVELOP DROPPING VISIBILITIES INTO
THE MVFR RANGE AT TIMES...BUT WILL NOT INDICATE ANY IFR DUE TO
EXPECTED BROKEN CLOUD COVER. BUT...IF CLOUD COVER IS LESS THAN
EXPECTED VISIBILITIES COULD CERTAINLY DROP INTO THE IFR/LIFR
RANGE.
MVFR CEILINGS WILL BE LIKELY AT THE COASTAL TERMINALS AFTER SUNRISE
OTHERWISE EXPECT VFR. SHOWERS AND THUNDERSTORMS WILL DEVELOP ALONG
THE COLD FRONT SOUTH OF THE TERMINALS BY AFTERNOON AND WILL LIKELY
SPREAD NORTHEASTWARD OVER THE TERMINALS DURING THE AFTERNOON.
EXTENDED OUTLOOK...CHANCE OF SHOWERS/EMBEDDED THUNDERSTORMS WITH
WIDESPREAD IFR FRIDAY. ISOLATED SHOWERS MONDAY MORNING. OTHERWISE
EXPECT VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 755 PM WEDNESDAY...BROAD AREA OF LOW PRESSURE ALONG AND WEST
TO EAST SOUTHWARD DROPPING FRONT WILL SLOWLY PUSH ACROSS THE WATERS
OVERNIGHT. SFC PG REMAINS SOMEWHAT RELAXED WITH WINDS SW-W AT 10 TO
OCCASIONALLY 15 KT OVERNIGHT. MODEL SFC PRESSURE FIELDS HAVE THE
FRONT DROPPING TO CAPE FEAR AT OR BEFORE SUNRISE THURSDAY. THE POST
FRONTAL NE SURGE FROM THE TIGHTENED PG ALONG WITH COLD AIR ADVECTION
WILL LAG BEHIND THE FRONT...AND LIKELY OCCUR DURING THE DAY ON
THURSDAY. SEAS PRIOR TO THE CFP AND THE DELAYED POST FRONTAL WIND
INCREASE...WILL RANGE FROM 2 TO 4 FT...POSSIBLY DROPPING TO AROUND 2
FT THROUGHOUT LATE IN THE PRE-DAWN HRS OF THURSDAY. A 1 TO 2 FT
EASTERLY GROUND SWELL EXHIBITING 11-13 SECOND PERIODS WILL BE 1 OF
THE PRIMARY DRIVERS FOR SIG. SEAS. THE CURRENT WIND DRIVEN 2-3 FT
RUNNING AT 3-5 SECOND PERIODS...WILL ACTUALLY SUBSIDE OVERNIGHT DUE
TO THE CURRENT 15 KT WIND SPEEDS DIMINISHING TO 10 TO OCCASIONALLY
15 KT. CONVECTION WILL SPORADICALLY MOVE OFF THE MAINLAND
TONIGHT...ESPECIALLY OFF THE NC MAINLAND.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 PM WEDNESDAY...UNSETTLED WEATHER EXPECTED FOR THE ENTIRE
SHORT TERM PERIOD WITH A SMALL CRAFT ADVISORY NOW SEEMINGLY LIKELY
BY THE LATTER HALF. COLD FRONT ORIENTED WEST-EAST WILL SINK
SOUTHWARD ACROSS THE WATERS ON THURSDAY BRINGING A CONSIDERABLE VEER
TO NORTHERLY WINDS. SEAS WILL BUILD WITH THE FROPA AND SCEC HARD TO
RULE OUT AT SOME POINT ESPECIALLY OVER THE MORE NORTHERN ZONES WHERE
THE GRADIENT MAY PINCH SOME. THE REAL DETERIORATION WILL COME JUST
AHEAD OF THE MAIN COLD SURGE LATE THURSDAY NIGHT INTO FRIDAY HOWEVER
AS LOW PRESSURE DEVELOPS ALONG THE WELL OFFSHORE BOUNDARY. SOLID
SMALL CRAFT ADVISORY WIND AND SEAS SEEM LIKELY. STILL JUST ENOUGH
MODEL DISCREPANCY FOR ENOUGH UNCERTAINTY TO RAISE FLAGS THIS FAR
OUT. BY FRIDAY HOWEVER SEAS COULD BE AS HIGH AS 5 TO 8 FT OR EVEN A
LITTLE HIGHER ACCORDING TO SWAN RUN IN A STEEP WIND CHOP.
LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 3 PM WEDNESDAY...NORTHERLY FLOW WILL STEADILY DECREASE SAT
INTO SUN AS PRESSURE GRADIENT RELAXES. SPEEDS AROUND 20 KT AT THE
START OF THE PERIOD DROP TO 10 TO 15 KT SAT NIGHT. SURFACE RIDGE
AXIS SHIFTS OFFSHORE SUN WITH FLOW BECOMING SOUTHWEST AHEAD OF
APPROACHING COLD FRONT. OFFSHORE FLOW DEVELOPS IN THE WAKE OF THE
FRONT...BUT MARGINAL GRADIENT AND LACK OF SIGNIFICANT COLD AIR KEEPS
SPEEDS IN THE 10 TO 15 KT RANGE THROUGH THE END OF THE PERIOD. SEAS
START OUT OVER 6 FT WELL AWAY FROM SHORE SAT BUT DECREASE IN WINDS
SAT INTO SUN ALLOWS SEAS TO FALL TO 2 TO 3 FT BY SUN. SEAS REMAIN 2
TO 3 FT THROUGH THE END OF THE PERIOD.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...MBB
NEAR TERM...DCH
SHORT TERM...MBB
LONG TERM...TRL
AVIATION...MRR
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
135 AM EDT TUE APR 3 2012
.SYNOPSIS...
WEAK HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT THROUGH EARLY
TUESDAY BEFORE IT MOVES OFFSHORE. A FRONT WILL RETURN NORTH AS A
WARM FRONT ON TUESDAY. ANOTHER COLD FRONT WILL TRACK SOUTH THROUGH
THE AREA WEDNESDAY NIGHT INTO THURSDAY FOLLOWED BY A REINFORCING
SHOT OF COLD AIR FRIDAY NIGHT INTO SATURDAY AS STRONG HIGH PRESSURE
BUILDS DOWN ACROSS THE SOUTHEAST.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1040 PM MONDAY...THE LEADING EDGE OF THE NE-E SURGE IS NOW
WEST AND SOUTH OF THE ILM CWA. THIS SURGE AT THIS TIME BEST
ILLUSTRATED WITH 11-3.9 MICRON SAT IMAGERY TRENDS OVERLAID WITH
LAPS SFC WIND FIELDS. LOOK FOR A MUCH MORE STABLE...COOLER AND DRIER
AIR MASS TO OVERSPREAD THE ILM CWA. THE COOLER AND DRIER PORTIONS OF
THIS AIR MASS WILL LIE ACROSS THE NE PORTIONS OF THE ILM CWA. WITH
THE SFC FRONT STALLING ALONG THE SAVANNAH RIVER VALLEY...A SHALLOWER
COOL/DRY AIR MASS CHANGE WILL LIE ACROSS THE SC PORTIONS OF THE ILM
CWA. THIS HAS RESULTED IN LOWER MINS BEING FORECAST ACROSS THE ILM
NC CWA...WITH ILM SC LOWS AS MUCH AS 4 TO 8 DEGREES HIER THEN THE
ILM NC CWA. NULL POPS FOR THE REMAINDER OF THE OVERNIGHT. NAMBUFR
SOUNDINGS FOR TONIGHT INDICATE POSSIBLE POST FRONTAL FEW TO SCT SC
MAINLY FOR THE ILM SC CWA...BUT FOR THE MOST PART WILL STICK WITH A
CLEAR/MOSTLY CLEAR SKY CONDITION.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 3 PM MONDAY...BACKDOOR COLD FRONT OFF TO THE SOUTH WILL ALLOW
RIDGE OF HIGH PRESSURE TO NOSE INTO THE CAROLINAS FROM THE NORTH
EARLY TUESDAY. THIS AIRMASS WILL QUICKLY SLIDE OFF THE COAST BY
AFTERNOON. SOME MOISTURE RETURN WILL BE ENSUE FROM WEST TO EAST
ACROSS THE CAROLINAS. IN THE UPPER LEVELS A SHORT AMPLITUDE RIDGE
WILL HOLD ON FOR THE MOST PART. MODELS STRUGGLING WITH SOME
CONVECTIVELY INDUCED VORT CENTERS EMANATING FROM TEXAS...AND
DEEPENING ON THE TRACK AND STRENGTH OF THESE FEATURES THEY MAY BE
ABLE TO SERVE AS SOME WEAK FORCING LOCALLY. BARRING THIS POSSIBILITY
MOST OF THE AREA LOOKS TO REMAIN RAIN-FREE WITH NEAR SEASONABLE
TEMPERATURES. ADVECTION OF WARMTH AND MOISTURE WILL CONTINUE FOR
THE REMAINDER OF THE PERIOD KEEPING TUESDAY NIGHT VERY MILD
ESPECIALLY DUE TO THE INCREASED CLOUD COVER. THE UPPER RIDGE WILL
CONTINUE TO BE WEAKENED ON WEDNESDAY ALLOWING CLEARER PASSAGE OF
SOME WEAK VORTICITY CENTERS. A PREFRONTAL PIEDMONT TROUGH WILL TEND
TO FOCUS MOST OF THE SCATTERED CONVECTION OVER WESTERN ZONES
INITIALLY. HOWEVER SINCE STORMS WILL HAVE A WELL DEFINED EASTWARD
MOTION THERE WILL BE ONLY A SLIGHT GRADIENT IN FCST POPS AT THIS
TIME. QPF WILL BE HIGHER OVER WRN ZONES (ALTHOUGH STILL QUITE LOW).
DESPITE THE CLOUD COVER MOST PLACES SHOULD HAVE NO TROUBLE SEEING A
HIGH IN THE LOW 80S. COLD FRONT ARRIVES LATE WEDNESDAY NIGHT AND
LOOKS QUITE MOISTURE-CHALLENGED.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
AS OF 3 PM MONDAY...PROGRESSIVE PATTERN WILL PREVAIL THROUGH THE
EXTENDED AS A MID LEVEL CYCLONE MOVES ACROSS EARLY FOLLOWED BY BRIEF
RIDGING. FINALLY...AT THE END OF THE PERIOD SUBTLE TROUGHING WILL
MOVE ACROSS. THE FORECAST CHALLENGES CONTINUE TO CENTER AROUND
TIMING AND MAGNITUDE FOR FRIDAY TRANSITIONING TO A TEMPERATURE
FORECAST FOR THE WEEKEND.
STILL SOME UNCERTAINTY WITH REGARDS TO THE CHARACTERISTIC OF THE
SYSTEM FRIDAY AS THE LATEST GFS...AND PAST COUPLE OF CYCLES FOR THAT
MATTER SHOW A CLOSED MID LEVEL CYCLONE MOVING ACROSS THE UPSTATE OF
SOUTH CAROLINA THEN OPENING UP AND MOVING OFF QUICKLY. THE ECMWF AND
ENSEMBLES ARE SIMILAR BUT A BIT FURTHER SOUTH. I HAVE INCREASED POPS
TO LIKELY FOR FRIDAY MATCHING HPC AND INCREASED POPS INTO SATURDAY
MORNING TO ADDRESS SLOWER TIMING WITH A SYSTEM THAT REMAINS CLOSED
FOR A LONGER PERIOD OF TIME.
TEMPERATURES DROP TO JUST BELOW CLIMATOLOGY SATURDAY AND SUNDAY
BEFORE REBOUNDING QUICKLY WITH A SOUTHWEST FLOW MONDAY. SUNDAY
SHOULD BE THE COOLEST MORNING COUPLED WITH THE BEST RADIATIONAL
CONDITIONS WITH MID TO UPPER 40S CWA WIDE. SOME CLIMATOLOGICALLY
FAVORED AREAS COULD SEE A DEGREE OR TWO BELOW 45.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
AS OF 06Z...LIGHT SHOWERS ARE EXPECTED TO REMAIN W AND S OF THE
TERMINALS THROUGH SUNRISE. DRIER AIR WILL CONTINUE TO PUSH DEWPOINTS
LOWER WITH DRIEST OF AIR AT LBT AND ILM. FRONT HAS STALLED AND
BECOME RATHER DIFFUSE AND WITH THAT...SOME MID CLOUDS WILL SPILL
BACK N ACROSS FLO AND PERHAPS MYR THROUGH SUNRISE. CONTINUED VFR
AFTER SUNRISE WITH VEERING WINDS TO THE SOUTHEAST BY AFTERNOON.
ISOLATED CONVECTION IS POSSIBLE...MAINLY AFTER 00Z AT FLO AND MYR AS
WARM FRONT PUSHES ACROSS THE AREA.
EXTENDED OUTLOOK...MODERATE CONFIDENCE ISOLATED/SCATTERED SHOWERS
AND THUNDERSTORMS WITH TEMPO MVFR WEDNESDAY THROUGH THURSDAY NIGHT.
A GOOD CHANCE OF SHOWERS/EMBEDDED THUNDERSTORMS WITH WIDESPREAD IFR
FRIDAY. VFR SATURDAY.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1040 PM MONDAY...POST FRONTAL NE-E SURGE ACCOMPANIED BY COLD
AIR ADVECTION HAS PUSHED SOUTH OF THE ILM WATERS...AND IS PROGGED TO
STALL IN THE VICINITY OF THE MOUTH OF THE SAVANNAH RIVER OVERNIGHT
INTO TUESDAY. CURRENT BUOY OBS AND HRRR WIND OUTPUT INDICATE SPEEDS
OF AROUND 15 KT FOR THE REMAINDER OF THE NIGHT...POSSIBLY DOWN TO
10-15 KT NORTH OF CAPE FEAR WHERE GRADIENT WILL RELAX SOME AND THE
POST FRONTAL CAA SURGE ENDS. LOOK FOR SEAS IN THE 2 TO 4 FT RANGE
THRUOUT. THE EXCEPTION WILL BE UP TO 5 FT ACROSS THE WATERS OFF CAPE
FEAR THROUGH MIDNIGHT. SEAS PRIMARILY A REFLECTION OF SHORT PERIOD
WIND DRIVEN WAVES RUNNING AT 4-5 SECOND PERIODS...ACCOMPANIED BY AN
UNDERLYING AND WEAK 1 FT OR LESS EASTERLY GROUND SWELL AT A 10
SECOND PERIOD.
SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
AS OF 3 PM MONDAY...NORTHEAST WINDS ON TUESDAY WITH A BACKDOOR FRONT
OFF TO THE SOUTH AND HIGH PRESSURE BUILDING IN FROM THE NORTH EARLY
TUESDAY. THIS HIGH WILL MOVE OFF THE COAST BY AFTERNOON BRINGING
VEERING AND PERHAPS DECREASING WINDS. VEERING CONTINUES TUESDAY
NIGHT BRINGING A MORE DEFINED SOUTHERLY COMPONENT. NO REAL SWELL
ENERGY ON THE RADAR SO SEAS GENERALLY 2 TO 3 FT THROUGHOUT.
WEDNESDAY BRINGS A PREFRONTAL SOUTHWESTERLY FLOW REGIME WITH A
TIGHTENING GRADIENT. THIS SHOULD ADD ABOUT A FOOT TO THE PREDOMINANT
WAVE HEIGHT.
LONG TERM /THURSDAY THROUGH SATURDAY/...
AS OF 3 PM MONDAY...NORTHEAST FLOW INITIALLY WILL VEER A BIT TO MORE
TO AN EASTERLY DIRECTION EARLY FRIDAY AS LOW PRESSURE DROPS WELL TO
THE SOUTH. STILL SOME UNCERTAINTY OF THE EXACT TIMING AND PLACEMENT
OF THE SYSTEM SO WE COULD SEE WINDS VEER EVEN MORE THROUGH FRIDAY
THAN THE CURRENT FORECAST ADVERTISES. NORTHEASTERLY FLOW LATE FRIDAY
THROUGH SATURDAY AS HIGH PRESSURE BUILDS IN BEHIND THE SYSTEM. AS
USUAL SURGES ARE DIFFICULT TO TIME BUT SHOULD SEE SEVERAL HOURS OF
SPEEDS NEAR 20 KNOTS ACROSS THE OUTER WATERS. WAVEWATCH SEAS
INCREASE FROM 2-4 FEET EARLY TO 4-7 FEET LATE IN THE PERIOD WITH THE
STRONGER FETCH.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...HOEHLER
SHORT TERM...BACON
LONG TERM...KEEBLER
AVIATION...RJD/DL
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
1200 PM CDT TUE APR 3 2012
.DISCUSSION.../ISSUED AT 954 AM CDT/
LOW/MID LEVEL CLOUD DECK REMAINS ENTRENCHED ACROSS SOUTHEASTERN
SOUTH DAKOTA AND BORDERING STATES THIS MORNING. 925-850MB RUC RH
PROGS INDICATE EROSION OF THIS DECK SHOULD CONTINUE INTO THE EARLY
AFTERNOON...ALTHOUGH EXPECT SOME RESIDUAL SCATTERED LOW/MID CLOUDS
UNTIL EVENING. TEMPS STILL LOOK TO BE COOLEST IN THE SOUTHEASTERN
CWA UNDER THE INFLUENCE OF THE CLOUD COVER...ALTHOUGH ABOVE NORMAL
HIGHS IN THE UPPER 50S TO LOWER 60S ARE STILL ANTICIPATED. BRISK
NORTHEAST WINDS WILL PERSIST THROUGH THE AFTERNOON...BUT REDUCE
BELOW 10 KTS AFTER DARK.
&&
.AVIATION.../FOR THE 18Z TAF ISSUANCE/
CIGS HAVE IMPROVED INTO THE VFR CATEGORY AT THE TAF SITES. OTHER
THAN FLEETING SCT CLOUDS CIRCA 2K FEET NEAR KSUX THIS AFTERNOON...VFR
CONDITIONS WITH CLEARING SKIES ARE EXPECTED. WINDS WILL CONTINUE
TO BE GUSTY OUT OF THE NORTHEAST THROUGH THE AFTERNOON...GENERALLY
AT SPEEDS OF 15 TO 25 KTS. MOSTLY CLEAR SKIES ARE EXPECTED TONIGHT
ALONG WITH SLIGHTLY DIMINISHING WINDS TO SPEEDS AOB 10 KTS. WINDS
WILL SHIFT TO MORE OF AN EASTERLY DIRECTIONAL COMPONENT FOR
WEDNESDAY...AND MID/HIGH CLOUDS WILL INCREASE TOWARD KSUX AS A LOW
PRESSURE SYSTEM PASSES TO THE SOUTH. PRECIPITATION ATTENDANT WITH
THE LOW PRESSURE AREA IS EXPECTED TO STAY TO THE SOUTH.
&&
.PREV DISCUSSION.../ISSUED AT 440 AM CDT/
A DECK OF LOW AND MID LEVEL STRATUS BEHIND THE SURFACE COLD FRONT
CURRENTLY ENCOMPASSES MUCH OF THE AREA. SEEING A FEW LIGHT SHOWERS
IN THE VICINITY OF THE 700MB FRONT...BUT THINK THESE WILL
DISSIPATE BY 12Z. MAIN FORECAST ISSUE TODAY WILL BE THE ERODING OF
THE CLOUD DECK AND THE ACCOMPANYING IMPACT ON HIGH TEMPERATURES.
THE COMBINATION OF DAYTIME HEATING AND LOW LEVEL DRY AIR ADVECTING
IN FROM THE NORTH SHOULD ACT TO SLOWLY RISE CEILINGS AND DISSIPATE
THE CLOUDS FROM NORTH TO SOUTH THROUGH THE DAY. FOLLOWED A
SOLUTION CLOSE TO HRRR...WHICH SEEMS TO HAVE A FAIRLY GOOD HANDLE
ON THINGS. 925MB TEMPS LOOK TO BE AROUND 12C THIS AFTERNOON. THUS
LOCATIONS THAT BECOME PARTLY TO MOSTLY SUNNY SHOULD GET INTO THE
LOW 60S. MEANWHILE...LOCATIONS THAT GET STUCK IN THE CLOUDS WILL
LIKELY REMAIN IN THE 50S. NORTHWEST IOWA AND PORTIONS OF SOUTHWEST
MINNESOTA ARE THE MOST LIKELY LOCATIONS TO STAY LOCKED IN. WENT
FOR HIGHS AROUND 60 IN THIS AREA GIVEN UNCERTAINTY...BUT WHERE THE
CLOUDS STAY...MAY NOT REACH 60. THINKING THE WARMEST TEMPS WILL BE
JUST NORTH OF THE CLOUD DECK THIS AFTERNOON...IN THE MITCHEL TO
LAKE ANDES AREA...THUS RAISED HIGHS SEVERAL DEGREES THERE. WINDS
WILL BE BLUSTERY TODAY OUT OF THE NORTHEAST. 900MB WINDS OF 20 TO
25KTS WILL PROMOTE WIND GUSTS UP TO AROUND 30 MPH THROUGH MUCH OF
THE DAY.
MOST LOCATIONS WILL BE MOSTLY CLEAR TONIGHT...EXCEPT ALONG AND SOUTH
OF THE MISSOURI RIVER...WHERE CLOUDS MAY STAY LOCKED IN. HOWEVER NOT
THINKING IT WILL BE A GREAT RADIATIONAL COOLING NIGHT WITH A 925MB
JET OF AROUND 30KTS KEEPING THE LOW LEVELS SOMEWHAT MIXED. THUS DID
NOT GO AS COLD AT THE MET GUIDANCE. DID GO ON THE COOLER SIDE OF THE
RAW GUIDANCE THOUGH...WITH THE COOL EAST NORTHEAST WIND ADVECTING IN
SOME COLDER AIR IN THE LOW LEVELS.
NEXT FORECAST ISSUE IS THE UPPER LEVEL LOW PRESSURE SYSTEM THAT WILL
MOVE ACROSS OKLAHOMA ON WEDNESDAY. THIS FURTHER SOUTH TRACK KEEPS
THE BEST FORCING TO OUR SOUTH. AT THE SAME TIME...EAST NORTHEAST
WINDS AROUND AN AREA OF HIGH PRESSURE OVER SOUTHERN CANADA WILL PUSH
DRIER AIR INTO OUR CWA. THE COMBINATION OF THESE FACTORS SHOULD KEEP
ALL THE PRECIP TO OUR SOUTH WITH THIS SYSTEM...AND THUS REMOVED
POPS. THIS IS SUPPORTED BY THE NAM...ECMWF AND SREF SOLUTIONS. HIGHS
WEDNESDAY WERE TRENDED WARMER GIVEN THE DRIER AND MORE SUNNY
FORECAST...GENERALLY GOING WITH UPPER 50S TO LOWER 60S. WEDNESDAY
NIGHT IS ANOTHER NIGHT WHICH WILL FEATURE A COOL EASTERLY COMPONENT
TO THE WIND. THUS WENT ON THE COLDER SIDE OF THE RAW GUIDANCE...BUT
NOT AS COLD AS MOS...WHICH APPEARS TO BE RADIATING THINGS TOO MICH.
NEXT WEATHER FEATURE WILL BE A SHORTWAVE THAT CROSSES THE REGION
FRIDAY NIGHT INTO SATURDAY. BEST QG FORCING WITH THIS FEATURE WILL
STAY TO OUR NORTH AND ANY INSTABILITY TO OUR SOUTH. SO THINKING ANY
RAIN WE GET FROM THIS WAVE WILL BE LIGHT. GIVEN THIS JUST KEPT POPS
IN THE CHANCE CATEGORY FOR NOW. GIVEN THE VERY MEAGER INSTABILITY
DECIDED TO REMOVE THE THUNDER WORDING FROM THE GRIDS.
THE REST OF THE FORECAST PERIOD SHOULD REMAIN DRY. ECMWF IS SLOWER
WITH OUR NEXT COLD FRONT THAN THE GFS...ALLOWING TEMPERATURES TO
WARM NICELY ON SUNDAY. ECMWF ENSEMBLE NOT QUITE AS SLOW AND WARM AS
THE OPERATIONAL...BUT STILL WARMER THAN THE GFS...THUS UPPED TEMPS
A FEW DEGREES INTO THE LOW TO MID 60S. MODELS AGREE THAT THE COLDEST
AIR BEHIND THE FRONT WILL BE OVER US ON MONDAY INTO MONDAY NIGHT.
HOWEVER THE GFS DIGS THE TROUGH FURTHER SOUTH PUSHING IN COLDER AIR
THAN THE ECMWF. ECMWF AND GFS ENSEMBLES ARE BOTH SEVERAL DEGREES
WARMER THAN THEIR OPERATIONAL RUNS AT 850MB. THUS TEND TO THINK THIS
WILL JUST BE A QUICK COLD SHOT WITH RIDGING QUICKLY BUILDING IN
BEHIND IT ONCE AGAIN. CURRENTLY GOING WITH HIGHS IN THE 50S
MONDAY...BUT GIVEN WHAT WAS JUST MENTIONED...WOULD NOT BE SURPRISED
TO SEE FUTURE SHIFTS TREND THESE UP A BIT...CLOSER TO THE ECMWF
VALUES. EITHER WAY...STILL WILL HAVE A CHILLY ATMOSPHERE OVER US
MONDAY NIGHT...WHICH COMBINED WITH SURFACE HIGH PRESSURE
OVERHEAD...SHOULD PROMOTE GOOD RADIATIONAL COOLING...AND WILL HAVE
TO WATCH FOR A POSSIBLE FREEZE OVER MUCH OF THE AREA. /CHENARD
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
MN...NONE.
NE...NONE.
SD...NONE.
&&
$$
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
954 AM CDT TUE APR 3 2012
.DISCUSSION...
LOW/MID LEVEL CLOUD DECK REMAINS ENTRENCHED ACROSS SOUTHEASTERN
SOUTH DAKOTA AND BORDERING STATES THIS MORNING. 925-850MB RUC RH
PROGS INDICATE EROSION OF THIS DECK SHOULD CONTINUE INTO THE EARLY
AFTERNOON...ALTHOUGH EXPECT SOME RESIDUAL SCATTERED LOW/MID CLOUDS
UNTIL EVENING. TEMPS STILL LOOK TO BE COOLEST IN THE SOUTHEASTERN
CWA UNDER THE INFLUENCE OF THE CLOUD COVER...ALTHOUGH ABOVE NORMAL
HIGHS IN THE UPPER 50S TO LOWER 60S ARE STILL ANTICIPATED. BRISK
NORTHEAST WINDS WILL PERSIST THROUGH THE AFTERNOON...BUT REDUCE
BELOW 10 KTS AFTER DARK.
&&
.PREV DISCUSSION... /ISSUED 440 AM CDT MON APR 3 2012/
A DECK OF LOW AND MID LEVEL STRATUS BEHIND THE SURFACE COLD FRONT
CURRENTLY ENCOMPASSES MUCH OF THE AREA. SEEING A FEW LIGHT SHOWERS
IN THE VICINITY OF THE 700MB FRONT...BUT THINK THESE WILL DISSIPATE
BY 12Z. MAIN FORECAST ISSUE TODAY WILL BE THE ERODING OF THE CLOUD
DECK AND THE ACCOMPANYING IMPACT ON HIGH TEMPERATURES. THE
COMBINATION OF DAYTIME HEATING AND LOW LEVEL DRY AIR ADVECTING IN
FROM THE NORTH SHOULD ACT TO SLOWLY RISE CEILINGS AND DISSIPATE THE
CLOUDS FROM NORTH TO SOUTH THROUGH THE DAY. FOLLOWED A SOLUTION
CLOSE TO HRRR...WHICH SEEMS TO HAVE A FAIRLY GOOD HANDLE ON THINGS.
925MB TEMPS LOOK TO BE AROUND 12C THIS AFTERNOON. THUS LOCATIONS
THAT BECOME PARTLY TO MOSTLY SUNNY SHOULD GET INTO THE LOW 60S.
MEANWHILE...LOCATIONS THAT GET STUCK IN THE CLOUDS WILL LIKELY
REMAIN IN THE 50S. NORTHWEST IOWA AND PORTIONS OF SOUTHWEST
MINNESOTA ARE THE MOST LIKELY LOCATIONS TO STAY LOCKED IN. WENT FOR
HIGHS AROUND 60 IN THIS AREA GIVEN UNCERTAINTY...BUT WHERE THE
CLOUDS STAY...MAY NOT REACH 60. THINKING THE WARMEST TEMPS WILL BE
JUST NORTH OF THE CLOUD DECK THIS AFTERNOON...IN THE MITCHEL TO LAKE
ANDES AREA...THUS RAISED HIGHS SEVERAL DEGREES THERE. WINDS WILL BE
BLUSTERY TODAY OUT OF THE NORTHEAST. 900MB WINDS OF 20 TO 25KTS WILL
PROMOTE WIND GUSTS UP TO AROUND 30 MPH THROUGH MUCH OF THE DAY.
MOST LOCATIONS WILL BE MOSTLY CLEAR TONIGHT...EXCEPT ALONG AND SOUTH
OF THE MISSOURI RIVER...WHERE CLOUDS MAY STAY LOCKED IN. HOWEVER NOT
THINKING IT WILL BE A GREAT RADIATIONAL COOLING NIGHT WITH A 925MB
JET OF AROUND 30KTS KEEPING THE LOW LEVELS SOMEWHAT MIXED. THUS DID
NOT GO AS COLD AT THE MET GUIDANCE. DID GO ON THE COOLER SIDE OF THE
RAW GUIDANCE THOUGH...WITH THE COOL EAST NORTHEAST WIND ADVECTING IN
SOME COLDER AIR IN THE LOW LEVELS.
NEXT FORECAST ISSUE IS THE UPPER LEVEL LOW PRESSURE SYSTEM THAT WILL
MOVE ACROSS OKLAHOMA ON WEDNESDAY. THIS FURTHER SOUTH TRACK KEEPS
THE BEST FORCING TO OUR SOUTH. AT THE SAME TIME...EAST NORTHEAST
WINDS AROUND AN AREA OF HIGH PRESSURE OVER SOUTHERN CANADA WILL PUSH
DRIER AIR INTO OUR CWA. THE COMBINATION OF THESE FACTORS SHOULD KEEP
ALL THE PRECIP TO OUR SOUTH WITH THIS SYSTEM...AND THUS REMOVED
POPS. THIS IS SUPPORTED BY THE NAM...ECMWF AND SREF SOLUTIONS. HIGHS
WEDNESDAY WERE TRENDED WARMER GIVEN THE DRIER AND MORE SUNNY
FORECAST...GENERALLY GOING WITH UPPER 50S TO LOWER 60S. WEDNESDAY
NIGHT IS ANOTHER NIGHT WHICH WILL FEATURE A COOL EASTERLY COMPONENT
TO THE WIND. THUS WENT ON THE COLDER SIDE OF THE RAW GUIDANCE...BUT
NOT AS COLD AS MOS...WHICH APPEARS TO BE RADIATING THINGS TOO MICH.
NEXT WEATHER FEATURE WILL BE A SHORTWAVE THAT CROSSES THE REGION
FRIDAY NIGHT INTO SATURDAY. BEST QG FORCING WITH THIS FEATURE WILL
STAY TO OUR NORTH AND ANY INSTABILITY TO OUR SOUTH. SO THINKING ANY
RAIN WE GET FROM THIS WAVE WILL BE LIGHT. GIVEN THIS JUST KEPT POPS
IN THE CHANCE CATEGORY FOR NOW. GIVEN THE VERY MEAGER INSTABILITY
DECIDED TO REMOVE THE THUNDER WORDING FROM THE GRIDS.
THE REST OF THE FORECAST PERIOD SHOULD REMAIN DRY. ECMWF IS SLOWER
WITH OUR NEXT COLD FRONT THAN THE GFS...ALLOWING TEMPERATURES TO
WARM NICELY ON SUNDAY. ECMWF ENSEMBLE NOT QUITE AS SLOW AND WARM AS
THE OPERATIONAL...BUT STILL WARMER THAN THE GFS...THUS UPPED TEMPS
A FEW DEGREES INTO THE LOW TO MID 60S. MODELS AGREE THAT THE COLDEST
AIR BEHIND THE FRONT WILL BE OVER US ON MONDAY INTO MONDAY NIGHT.
HOWEVER THE GFS DIGS THE TROUGH FURTHER SOUTH PUSHING IN COLDER AIR
THAN THE ECMWF. ECMWF AND GFS ENSEMBLES ARE BOTH SEVERAL DEGREES
WARMER THAN THEIR OPERATIONAL RUNS AT 850MB. THUS TEND TO THINK THIS
WILL JUST BE A QUICK COLD SHOT WITH RIDGING QUICKLY BUILDING IN
BEHIND IT ONCE AGAIN. CURRENTLY GOING WITH HIGHS IN THE 50S
MONDAY...BUT GIVEN WHAT WAS JUST MENTIONED...WOULD NOT BE SURPRISED
TO SEE FUTURE SHIFTS TREND THESE UP A BIT...CLOSER TO THE ECMWF
VALUES. EITHER WAY...STILL WILL HAVE A CHILLY ATMOSPHERE OVER US
MONDAY NIGHT...WHICH COMBINED WITH SURFACE HIGH PRESSURE
OVERHEAD...SHOULD PROMOTE GOOD RADIATIONAL COOLING...AND WILL HAVE
TO WATCH FOR A POSSIBLE FREEZE OVER MUCH OF THE AREA. /CHENARD
&&
.AVIATION.../FOR THE 12Z TAF ISSUANCE/
THIS MORNING...THERE WILL BE AREAS OF MVFR CEILINGS EXCEPT IN OUR NW
ZONES WHO ARE CURRENTLY CLEARING OUT. BY MIDDAY...MOST OF THE MVFR
CEILINGS SHOULD BE GONE...EITHER BY MIXING TO A VFR CATEGORY...OR BY
CLEARING OUT ENTIRELY. THEREFORE THIS AFTERNOON AND TONIGHT...OUR
FORECAST AREA SHOULD BE VFR. NORTHERLY WINDS WILL GUST AT TIMES TO
AROUND 25 KNOTS TODAY...BECOMING A BIT MORE NORTHEAST THIS
AFTERNOON. /MJF
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
MN...NONE.
NE...NONE.
SD...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1235 PM CDT TUE APR 3 2012
.DISCUSSION...
SEE THE 18Z AVIATION DISCUSSION BELOW.
&&
.AVIATION...
VFR CONDITIONS ARE EXPECTED ACROSS WEST CENTRAL TX THROUGH THE
NEXT 24 HOURS. DRY AIR ASSOCIATED WITH THE PACIFIC COLD FRONT HAS
MOVED EAST OF THE TAF SITES...RESULTING IN SOME HIGH BASED CU THIS
AFTERNOON GENERALLY BETWEEN 6-10 KFT. THIS CLOUD COVER WILL
DIMINISH QUICKLY AROUND 00Z PROVIDING MOSTLY CLEAR SKIES
OVERNIGHT. WEST WINDS WILL INCREASE TO AROUND 15 KTS AT
KABI/KSJT/KSOA AND SLIGHTLY WEAKER AT KBBD/KJCT. HOWEVER...WIND
SPEEDS WILL DIMINISH AROUND SUNSET AS WELL. A SECONDARY SURFACE
BOUNDARY WILL MOVE ACROSS THE AREA TONIGHT...SHIFTING WINDS TO THE
NORTHWEST...MAINLY AFTER MIDNIGHT. WE MAY SEE SOME LOW/MID LEVEL
CIGS DEVELOP IN THE BIG COUNTRY BUT I EXPECT THIS TO REMAIN NORTH
OF KABI AT THIS TIME.
EQUIPMENT NOTE...KBBD CEILOMETER IS CURRENTLY NOT WORKING. THE
APPROPRIATE OFFICIALS HAVE BEEN ADVISED BUT NO RETURN TO SERVICE
TIME IS KNOWN. THUS...NO SKY BASED AMENDMENTS ARE EXPECTED TO BE
MADE UNTIL THE EQUIPMENT IS REPAIRED.
JOHNSON
&&
.PREV DISCUSSION... /ISSUED 1116 AM CDT TUE APR 3 2012/
UPDATE...
THE PACIFIC COLD FRONT HAS MOVED ACROSS MUCH OF THE CWA THIS
MORNING...STRETCHING FROM NEAR MILLERS CREEK RESERVOIR...TO
CROSS PLAINS...TO RICHLAND SPRINGS. A FEW SHOWERS AND
THUNDERSTORMS WILL CONTINUE ALONG/EAST OF THIS FRONT THROUGH EARLY
AFTERNOON BEFORE THE PACIFIC FRONT NUDGES THE AMPLE LOW LEVEL
MOISTURE OFF TO THE EAST. THE SEVERE THREAT APPEARS TO HAVE ENDED
FOR THE CWA WITH THE INSTABILITY AXIS SHIFTING OVER EAST TX. POPS
WERE TRIMMED TO ONLY INCLUDE THE EASTERN 1/4 OF THE AREA THROUGH
EARLY AFTERNOON WITH THE REST OF THE AREA REMAINING DRY. TO THE
WEST OF THIS BOUNDARY...DEWPOINTS HAVE FALLEN GENERALLY INTO THE
20S AND 30S WITH CLEARING SKIES AND WEST WINDS AROUND 10 MPH.
THESE WINDS WILL INCREASE TO 10-20 MPH THIS AFTERNOON...COMBINING
WITH RELATIVE HUMIDITIES OF 8-15 PERCENT TO CREATE ELEVATED FIRE
WEATHER CONDITIONS THIS AFTERNOON. CRITICAL THRESHOLDS SHOULD NOT
BE MET AND WILL KEEP MENTION OF THIS THREAT IN THE FWF AND HWO. A
FEW SPRINKLES WILL BE POSSIBLE FROM SWEETWATER TO HASKELL IN THE
AREA ASSOCIATED WITH MESOSCALE ASCENT TIED TO THE UPPER JET
STREAK. HOWEVER...GIVEN THE DEWPOINT DEPRESSIONS OF 50 DEGREES AS
OF 11 AM AND VERY DRY SUB CLOUD LAYER...MOST...IF NOT ALL...OF
THIS PRECIP WILL EVAPORATE BEFORE REACHING THE GROUND.
I REDUCED SKY COVER FOR MUCH OF THE AREA TODAY AND CLEANED UP
DEWPOINTS/WINDS FOR THE REMAINDER OF THE FIRST PERIOD. TEMPS
LOOKED GOOD SO NO CHANGES WERE NECESSARY.
JOHNSON
PREV DISCUSSION... /ISSUED 701 AM CDT TUE APR 3 2012/
DISCUSSION...
SEE 12Z AVIATION DISCUSSION BELOW.
AVIATION...
GENERALLY A VFR FORECAST TODAY WITH TEMPO MVFR CONDITIONS ASSOCIATED
WITH CONVECTION THIS MORNING. LIGHT WEST TO NORTHWEST WINDS EARLY
THIS MORNING WILL GUST TO AROUND 20 KT AFTER 17Z...THEN DIMINISH
BY SUNSET. VFR CONDITIONS WILL PREVAIL OVERNIGHT WITH LIGHT WINDS.
PREV DISCUSSION... /ISSUED 357 AM CDT TUE APR 3 2012/
SHORT TERM...
POTENT UPPER LOW OVER NEW MEXICO WILL SLOWLY MOVE EAST INTO THE
TEXAS HANDLE TONIGHT. PACIFIC FRONT HAS PUSHED EAST OF A JUNCTION...
BRADY... ABILENE...HASKELL LINE. IT WAS STILL UNSTABLE ALONG AND
AHEAD OF THE FRONT WITH RUC MUCAPES OF 2000 J/KG AND 0-6 KM SHEARS
OF 40 KTS. CAN NOT RULE OUT AN ISOLATED SEVERE THUNDERSTORMS EAST
OF THE PACIFIC FRONT THIS MORNING. HOWEVER...DRIER WESTERLY AIR AT
THIS SURFACE WILL WORK EASTWARD BY NOON...ENDING THE SEVERE
THREAT. THERE AS OUTSIDE CHANCE OF A SHOWER...AS 700 MB MOISTURE
WAS WRAPPED AROUND THE UPPER THIS MORNING ACROSS WEST TEXAS. THIS IS
EXPECTED TO MOVE NORTH OF THE REGION BY EARLY AFTERNOON.
OTHERWISE...DRY DESERT AIR AT THE SURFACE WILL BE GUSTY AT TIMES
THIS AFTERNOON...ELEVATING FIRE WEATHER CONDITIONS.
LONG TERM...
GUSTY WEST WINDS WILL AGAIN ELEVATE FIRE CONDITIONS WEDNESDAY AS
SURFACE LOW IN NW TEXAS MOVES NE INTO CENTRAL OKLAHOMA. COOL AIR
FILTERS IN WEDNESDAY NIGHT AS A WEAK COLD FRONT MOVES INTO THE
REGION. LATER THIS WEEK...THERE IS STILL THE POTENTIAL FOR DRYLINE
THUNDERSTORMS FRIDAY NIGHT. A COLD FRONT SATURDAY WILL ALSO BRING A
CHANCE FOR THUNDERSTORMS...MAINLY SOUTH OF THE I-20 CORRIDOR.
ADDED SLIGHT CHANCE OF STORMS SATURDAY NIGHT AND SUNDAY WITH LIFT
OF MOISTURE OVER THE FRONT. CONFIDENCE REMAINS LOW HOWEVER SO KEPT
POPS AT 20 PERCENT.
FIRE WEATHER.
GUSTY DRY WEST WINDS WILL ELEVATED FIRE DANGER THIS AFTERNOON AND
WEDNESDAY AFTERNOON...AS A SURFACE LOW IN NW TEXAS MOVES INTO
CENTRAL OKLAHOMA. WINDS SPEEDS ARE EXPECTED TO REMAIN BELOW
CRITICAL LEVELS.
04
&&
.PRELIMINARY POINT TEMPS/POPS...
ABILENE 50 81 49 83 52 / 0 0 0 0 0
SAN ANGELO 47 85 49 90 54 / 0 0 0 0 0
JUNCTION 46 87 48 91 58 / 0 0 0 0 0
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
25
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
701 AM CDT TUE APR 3 2012
.DISCUSSION...
SEE 12Z AVIATION DISCUSSION BELOW.
&&
.AVIATION...
GENERALLY A VFR FORECAST TODAY WITH TEMPO MVFR CONDITIONS ASSOCIATED
WITH CONVECTION THIS MORNING. LIGHT WEST TO NORTHWEST WINDS EARLY
THIS MORNING WILL GUST TO AROUND 20 KT AFTER 17Z...THEN DIMINISH
BY SUNSET. VFR CONDITIONS WILL PREVAIL OVERNIGHT WITH LIGHT WINDS.
&&
.PREV DISCUSSION... /ISSUED 357 AM CDT TUE APR 3 2012/
SHORT TERM...
POTENT UPPER LOW OVER NEW MEXICO WILL SLOWLY MOVE EAST INTO THE
TEXAS HANDLE TONIGHT. PACIFIC FRONT HAS PUSHED EAST OF A JUNCTION...
BRADY... ABILENE...HASKELL LINE. IT WAS STILL UNSTABLE ALONG AND
AHEAD OF THE FRONT WITH RUC MUCAPES OF 2000 J/KG AND 0-6 KM SHEARS
OF 40 KTS. CAN NOT RULE OUT AN ISOLATED SEVERE THUNDERSTORMS EAST
OF THE PACIFIC FRONT THIS MORNING. HOWEVER...DRIER WESTERLY AIR AT
THIS SURFACE WILL WORK EASTWARD BY NOON...ENDING THE SEVERE
THREAT. THERE AS OUTSIDE CHANCE OF A SHOWER...AS 700 MB MOISTURE
WAS WRAPPED AROUND THE UPPER THIS MORNING ACROSS WEST TEXAS. THIS IS
EXPECTED TO MOVE NORTH OF THE REGION BY EARLY AFTERNOON.
OTHERWISE...DRY DESERT AIR AT THE SURFACE WILL BE GUSTY AT TIMES
THIS AFTERNOON...ELEVATING FIRE WEATHER CONDITIONS.
LONG TERM...
GUSTY WEST WINDS WILL AGAIN ELEVATE FIRE CONDITIONS WEDNESDAY AS
SURFACE LOW IN NW TEXAS MOVES NE INTO CENTRAL OKLAHOMA. COOL AIR
FILTERS IN WEDNESDAY NIGHT AS A WEAK COLD FRONT MOVES INTO THE
REGION. LATER THIS WEEK...THERE IS STILL THE POTENTIAL FOR DRYLINE
THUNDERSTORMS FRIDAY NIGHT. A COLD FRONT SATURDAY WILL ALSO BRING A
CHANCE FOR THUNDERSTORMS...MAINLY SOUTH OF THE I-20 CORRIDOR.
ADDED SLIGHT CHANCE OF STORMS SATURDAY NIGHT AND SUNDAY WITH LIFT
OF MOISTURE OVER THE FRONT. CONFIDENCE REMAINS LOW HOWEVER SO KEPT
POPS AT 20 PERCENT.
FIRE WEATHER.
GUSTY DRY WEST WINDS WILL ELEVATED FIRE DANGER THIS AFTERNOON AND
WEDNESDAY AFTERNOON...AS A SURFACE LOW IN NW TEXAS MOVES INTO
CENTRAL OKLAHOMA. WINDS SPEEDS ARE EXPECTED TO REMAIN BELOW
CRITICAL LEVELS.
04
&&
.PRELIMINARY POINT TEMPS/POPS...
ABILENE 79 50 81 49 83 / 20 10 0 0 0
SAN ANGELO 82 47 85 49 90 / 20 10 0 0 0
JUNCTION 81 46 87 48 91 / 20 10 0 0 0
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
99/99/24
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
357 AM CDT TUE APR 3 2012
.SHORT TERM...
POTENT UPPER LOW OVER NEW MEXICO WILL SLOWLY MOVE EAST INTO THE
TEXAS HANDLE TONIGHT. PACIFIC FRONT HAS PUSHED EAST OF A JUNCTION...
BRADY... ABILENE...HASKELL LINE. IT WAS STILL UNSTABLE ALONG AND
AHEAD OF THE FRONT WITH RUC MUCAPES OF 2000 J/KG AND 0-6 KM SHEARS
OF 40 KTS. CAN NOT RULE OUT AN ISOLATED SEVERE THUNDERSTORMS EAST
OF THE PACIFIC FRONT THIS MORNING. HOWEVER...DRIER WESTERLY AIR AT
THIS SURFACE WILL WORK EASTWARD BY NOON...ENDING THE SEVERE
THREAT. THERE AS OUTSIDE CHANCE OF A SHOWER...AS 700 MB MOISTURE
WAS WRAPPED AROUND THE UPPER THIS MORNING ACROSS WEST TEXAS. THIS IS
EXPECTED TO MOVE NORTH OF THE REGION BY EARLY AFTERNOON.
OTHERWISE...DRY DESERT AIR AT THE SURFACE WILL BE GUSTY AT TIMES
THIS AFTERNOON...ELEVATING FIRE WEATHER CONDITIONS.
.LONG TERM...
GUSTY WEST WINDS WILL AGAIN ELEVATE FIRE CONDITIONS WEDNESDAY AS
SURFACE LOW IN NW TEXAS MOVES NE INTO CENTRAL OKLAHOMA. COOL AIR
FILTERS IN WEDNESDAY NIGHT AS A WEAK COLD FRONT MOVES INTO THE
REGION. LATER THIS WEEK...THERE IS STILL THE POTENTIAL FOR DRYLINE
THUNDERSTORMS FRIDAY NIGHT. A COLD FRONT SATURDAY WILL ALSO BRING A
CHANCE FOR THUNDERSTORMS...MAINLY SOUTH OF THE I-20 CORRIDOR.
ADDED SLIGHT CHANCE OF STORMS SATURDAY NIGHT AND SUNDAY WITH LIFT
OF MOISTURE OVER THE FRONT. CONFIDENCE REMAINS LOW HOWEVER SO KEPT
POPS AT 20 PERCENT.
.FIRE WEATHER.
GUSTY DRY WEST WINDS WILL ELEVATED FIRE DANGER THIS AFTERNOON AND
WEDNESDAY AFTERNOON...AS A SURFACE LOW IN NW TEXAS MOVES INTO
CENTRAL OKLAHOMA. WINDS SPEEDS ARE EXPECTED TO REMAIN BELOW
CRITICAL LEVELS.
04
&&
.PRELIMINARY POINT TEMPS/POPS...
ABILENE 79 50 81 49 83 / 10 10 0 0 0
SAN ANGELO 84 47 85 49 90 / 10 10 0 0 0
JUNCTION 81 46 87 48 91 / 20 10 0 0 0
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
99/04
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
1151 PM CDT MON APR 2 2012
.UPDATE...
HOISTED A WIND ADVISORY FOR THE WESTERN AND CENTRAL OK PANHANDLE AND
NORTHWEST TX PANHANDLE THROUGH 09Z. COLD FRONT FINALLY STARTING TO
SURGE SOUTH THROUGH THESE AREAS...WITH TIGHT GRADIENT NORTHWEST OF
SURFACE LOW OVER TX PANHANDLE SUPPORTING ADVISORY LEVEL WINDS.
BELIEVE THE TIGHTEST GRADIENT WILL REMAIN FOCUSED ACROSS THIS
NORTHWEST PORTION OF THE CWA AND THUS WILL KEEP ADVISORY CONFINED TO
THIS AREA FOR NOW. SEVERE WEATHER THREAT HAS ENDED ACROSS THE AREA
BUT WILL CONTINUE TO SEE SHOWER AND THUNDERSTORM CHANCES
OVERNIGHT...AND COULD SEE SOME LIGHT SNOW IN THE FAR NORTHWEST CWA
/AS IS CURRENTLY BEING REPORTED AT CLAYTON NM/. EXPECT SNOW
ACCUMULATIONS...IF ANY...TO BE VERY LIGHT. BEST PRECIP CHANCES WILL
BE ACROSS THE NORTH/NORTHWEST CWA FOR THE REST OF TONIGHT WHERE
MID/UPPER FORCING WILL MEET UP WITH BETTER MOISTURE ALONG AND NORTH
OF THE COLD FRONT.
KB
&&
.PREV DISCUSSION... /ISSUED 1142 PM CDT MON APR 2 2012/
AVIATION...
CLOSED UPPER LOW OVER EASTERN NEW MEXICO TONIGHT ALONG WITH A COLD
FRONT WILL ALLOW FOR MAINLY SHOWERS AT THE DALHART AND GUYMON TAF
SITES THROUGH ABOUT 00Z TO 03Z WEDNESDAY. LEFT ANY MENTION OF SHOWERS
OUT OF THE AMARILLO TAF SITE DUE TO LOW CONFIDENCE...HOWEVER NOT
RULING OUT COMPLETELY. NORTHERLY WINDS WILL BE STRONG INITIALLY AT
THE DALHART AND GUYMON TAF SITES...AROUND 25 TO 35 KNOTS SUSTAINED
WITH HIGHER GUSTS...BUT SHOULD DIMINISH TO AROUND 15 TO 25 KNOTS BY
15Z TUESDAY AND CONTINUING THROUGH 06Z WEDNESDAY. WINDS ARE EXPECTED
TO SHIFT TO THE NORTH APPROXIMATELY 06Z TUESDAY WITH SPEEDS ONLY
ABOUT 10 TO 20 KNOTS WITH SOME HIGHER GUSTS POSSIBLE.
SCHNEIDER
PREV DISCUSSION... /ISSUED 936 PM CDT MON APR 2 2012/
UPDATE...
HAVE EXTENDED THE WIND ADVISORY ACROSS CIMARRON COUNTY THROUGH
MIDNIGHT...AND ALLOWED IT TO EXPIRE FOR DALLAM AND HARTLEY COUNTIES.
LATEST OBSERVATIONAL AND SHORT-RANGE MODEL DATA SHOW A TIGHT LOW-
LEVEL PRESSURE GRADIENT/REINFORCING SURGE OF NORTH/NORTHEAST WINDS TO
IMPACT THE WESTERN OK PANHANDLE OVER THE NEXT FEW HOURS. RECENT OBS
FROM KENTON...BOISE CITY...AND SPRINGFIELD CONTINUE TO SHOW ADVISORY
LEVEL WINDS...AND KENTON JUST BRIEFLY HIT HIGH WIND WARNING CRITERIA.
LET THE RED FLAG WARNING ACROSS THE SOUTHWEST/SOUTH CENTRAL TX
PANHANDLE EXPIRE AS SCHEDULED AT 9 PM. WINDS HAVE DIMINISHED TO LESS
THAN 20 MPH AND RELATIVE HUMIDITIES WILL CONTINUE TO INCREASE
OVERNIGHT.
ALSO ADJUSTED PRECIP CHANCES FOR THE REST OF TONIGHT BASED ON LATEST
RADAR TRENDS. LINE OF CONVECTION RAPIDLY DEVELOPED AS PACIFIC COLD
FRONT OVERTOOK DRYLINE. THIS LINE OF SEVERE CONVECTION WILL CONTINUE
TO PIVOT NORTHEAST AHEAD OF POTENT MID-LEVEL VORT MAX ROUNDING CLOSED
LOW OVER NM. MAIN FOCUS FOR PRECIPITATION EXPECTED TO SET UP OVER THE
NORTHERN CWA AFTER MIDNIGHT AS VORT LOBE CONTINUES TO PIVOT NORTH AND
EVENTUALLY NORTHWEST. SEVERE THREAT WILL LINGER THE LONGEST ACROSS
THE NORTHEAST TX PANHANDLE AND EASTERN HALF OF THE OK PANHANDLE...BUT
WILL EVENTUALLY DIMINISH THERE AS WELL LATER TONIGHT AS PACIFIC FRONT
CONTINUES TO PUSH EAST AND STATIONARY FRONT ACROSS NORTHERN CWA
EVENTUALLY PUSHES SOUTHEAST...SQUEEZING THE DEEPER LOW-LEVEL MOISTURE
AND ASSOCIATED INSTABILITY EASTWARD.
KB
PREV DISCUSSION... /ISSUED 634 PM CDT MON APR 2 2012/
UPDATE...
EXPANDED SEVERE THUNDERSTORM WATCH ONE TIER OF COUNTIES WESTWARD.
SURFACE FRONT DRAPED SOUTH/SOUTHWEST ACROSS THE EASTERN OK AND
NORTHEAST TEXAS PANHANDLE...AND DRYLINE EXTENDING SOUTH FROM THE
FRONT ACROSS THE EASTERN TX PANHANDLE...WERE RETREATING TO THE WEST
AND NORTHWEST IN RESPONSE TO SURFACE LOW DEVELOPING NORTHEAST INTO
THE TX PANHANDLE AHEAD OF STRONG MID-LEVEL VORT MAX PIVOTING AROUND
CLOSED MID/UPPER-LEVEL LOW OVER NM. LATEST RUC GUIDANCE SHOWS THIS
BOUNDARY WILL CONTINUE TO RETREAT A LITTLE FARTHER EARLY THIS
EVENING...BEFORE DRYLINE ACROSS SOUTHEAST TX PANHANDLE GETS OVERTAKEN
BY PACIFIC FRONT AND SHOVED EASTWARD.
KB
PREV DISCUSSION... /ISSUED 625 PM CDT MON APR 2 2012/
UPDATE...
CONVECTION WILL CONTINUE TO DEVELOP IN RESPONSE TO A COLD FRONT
ACROSS THE PANHANDLES AND APPROACHING UPPER LOW FROM NEW MEXICO. THIS
CONVECTION WILL AFFECT ALL OF THE TAF SITES THROUGH 10Z TUESDAY. VFR
CONDITIONS WILL PREVAIL EXCEPT MVFR TO POSSIBLY IFR CONDITIONS IN AND
NEAR THE CONVECTION. WINDS WILL BECOME NORTHERLY TO NORTHEASTERLY 15
AND 20 TO 25 AND 30 KNOTS WITH HIGHER GUSTS BEHIND THE COLD
FRONT...WITH SOUTHERLY TO SOUTHWESTERLY WINDS AHEAD OF THE FRONT
MAINLY THIS EVENING AT THE AMARILLO TAF SITE.
SCHNEIDER
PREV DISCUSSION... /ISSUED 336 PM CDT MON APR 2 2012/
DISCUSSION...
UPPER LEVEL LOW HAS CUTOFF FROM THE FLOW OVER CENTRAL NEW
MEXICO. THIS LOW IS EXPECTED TO SLOWLY LIFT NORTHEAST THROUGH
NORTHEAST NEW MEXICO AND ACROSS THE NORTHWEST PART OF OUR
CWA INTO SOUTHWEST KANSAS BY WEDNESDAY AFTERNOON. A SURFACE
COLD FRONT HAS STALLED NEAR THE CANADIAN RIVER VALLEY THIS
AFTERNOON. THIS FRONT MAY LIFT BACK TO THE NORTH BRIEFLY
THIS EVENING BEFORE MOVE SOUTHEAST AGAIN LATER TONIGHT. THE
COLD FRONT WILL THEN STALL AGAIN BY TUESDAY AFTERNOON ACROSS
THE FAR SOUTHEAST TEXAS PANHANDLE BEFORE MOVING SOUTH OF THE
TEXAS PANHANDLE BY TUESDAY EVENING.
WILL KEEP THE NORTHWEST CWA UNDER A WIND ADVISORY THROUGH
THE MID EVENING AS WINDS ARE EXPECTED TO PICK UP AGAIN BY
EARLY THIS EVENING AS ANOTHER SURGE OF COLDER AIR MOVES
SOUTH. SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE ACROSS THE
EASTERN CWA ALONG A DRYLINE AND THEN THE BEST CHANCE OF SHOWERS AND
STORMS WILL BE ALONG AND BEHIND THE COLD FRONT ACROSS THE NORTHERN
CWA. THIS UPPER LEVEL LOW WILL HAVE SEVERAL SPOKES OF VORTICITY
ROTATING AROUND IT AS WELL...SO THE SHOWER AND THUNDERSTORM
POTENTIAL WILL PICK UP EACH TIME ONE THESE MOVES OVER THE REGION.
ON TUESDAY...WILL KEEP THE SHOWERS AND THUNDERSTORMS GOING AS THE
COLD CORE OF THE LOW MOVES OVER THE PANHANDLES. FORECAST SOUNDINGS
DO SHOW SOME INSTABILITY ON TUESDAY. PRECIPITATION CHANCES DECREASE
FROM SOUTHWEST TO NORTHEAST TUESDAY NIGHT INTO WEDNESDAY MORNING AS
THE UPPER LOW MOVES AWAY.
UPPER LEVEL SHORT WAVE RIDGING TAKES OVER THE HIGH PLAINS
WEDNESDAY NIGHT THROUGH THURSDAY NIGHT AHEAD OF ANOTHER LARGE UPPER
LEVEL TROUGH MOVING INTO THE PACIFIC NORTHWEST.
A DRYLINE IS EXPECTED TO MOVE TO THE EASTERN CWA BY FRIDAY
AFTERNOON. THIS DRYLINE WILL HOLD IN THE EASTERN CWA FRIDAY NIGHT AS
THE WIND SHEAR ALOFT INCREASES AS THE UPPER TROUGH MOVES ACROSS THE
NORTHERN HIGH PLAINS. THE INCREASED WIND SHEAR AND INSTABILITY MAY
LEAD TO THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS ACROSS THE
EASTERN CWA FRIDAY NIGHT...SO HAVE ADDED SOME SLIGHT CHANCE POPS
FOR NOW.
A COLD FRONT MOVES SOUTH ACROSS THE CWA ON SATURDAY NIGHT...COOLING
SUNDAY/S HIGHS BACK 10 TO 15 DEGREES.
FIRE WEATHER...
WILL CONTINUE TO HOLD ONTO THE RED FLAG WARNING FOR THE
SOUTHWEST AND SOUTH CENTRAL TEXAS PANHANDLE THROUGH EARLY
THIS EVENING. SOUTHWEST WINDS SHOULD INCREASE THROUGH THE
REST OF THE AFTERNOON INTO EARLY THIS EVENING AS A SURFACE
LOW INTENSIFIES OVER THE CENTRAL TEXAS PANHANDLE. THE WINDS
WILL THEN PICK UP BEHIND A COLD FRONT TONIGHT...ESPECIALLY
ACROSS THE NORTHWEST CWA...BUT RELATIVE HUMIDITIES WILL BE
ABOVE 20 PERCENT. THE CHANCES OF RAIN INCREASE TONIGHT THROUGH
TUESDAY.
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...WIND ADVISORY UNTIL 4 AM CDT TUESDAY FOR THE FOLLOWING ZONES:
DALLAM...HARTLEY...SHERMAN.
OK...WIND ADVISORY UNTIL 4 AM CDT TUESDAY FOR THE FOLLOWING ZONES:
CIMARRON...TEXAS.
&&
$$
11/08
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
1142 PM CDT MON APR 2 2012
.AVIATION...
CLOSED UPPER LOW OVER EASTERN NEW MEXICO TONIGHT ALONG WITH A COLD
FRONT WILL ALLOW FOR MAINLY SHOWERS AT THE DALHART AND GUYMON TAF
SITES THROUGH ABOUT 00Z TO 03Z WEDNESDAY. LEFT ANY MENTION OF SHOWERS
OUT OF THE AMARILLO TAF SITE DUE TO LOW CONFIDENCE...HOWEVER NOT
RULING OUT COMPLETELY. NORTHERLY WINDS WILL BE STRONG INITIALLY AT
THE DALHART AND GUYMON TAF SITES...AROUND 25 TO 35 KNOTS SUSTAINED
WITH HIGHER GUSTS...BUT SHOULD DIMINISH TO AROUND 15 TO 25 KNOTS BY
15Z TUESDAY AND CONTINUING THROUGH 06Z WEDNESDAY. WINDS ARE EXPECTED
TO SHIFT TO THE NORTH APPROXIMATELY 06Z TUESDAY WITH SPEEDS ONLY
ABOUT 10 TO 20 KNOTS WITH SOME HIGHER GUSTS POSSIBLE.
SCHNEIDER
&&
.PREV DISCUSSION... /ISSUED 936 PM CDT MON APR 2 2012/
UPDATE...
HAVE EXTENDED THE WIND ADVISORY ACROSS CIMARRON COUNTY THROUGH
MIDNIGHT...AND ALLOWED IT TO EXPIRE FOR DALLAM AND HARTLEY COUNTIES.
LATEST OBSERVATIONAL AND SHORT-RANGE MODEL DATA SHOW A TIGHT LOW-
LEVEL PRESSURE GRADIENT/REINFORCING SURGE OF NORTH/NORTHEAST WINDS TO
IMPACT THE WESTERN OK PANHANDLE OVER THE NEXT FEW HOURS. RECENT OBS
FROM KENTON...BOISE CITY...AND SPRINGFIELD CONTINUE TO SHOW ADVISORY
LEVEL WINDS...AND KENTON JUST BRIEFLY HIT HIGH WIND WARNING CRITERIA.
LET THE RED FLAG WARNING ACROSS THE SOUTHWEST/SOUTH CENTRAL TX
PANHANDLE EXPIRE AS SCHEDULED AT 9 PM. WINDS HAVE DIMINISHED TO LESS
THAN 20 MPH AND RELATIVE HUMIDITIES WILL CONTINUE TO INCREASE
OVERNIGHT.
ALSO ADJUSTED PRECIP CHANCES FOR THE REST OF TONIGHT BASED ON LATEST
RADAR TRENDS. LINE OF CONVECTION RAPIDLY DEVELOPED AS PACIFIC COLD
FRONT OVERTOOK DRYLINE. THIS LINE OF SEVERE CONVECTION WILL CONTINUE
TO PIVOT NORTHEAST AHEAD OF POTENT MID-LEVEL VORT MAX ROUNDING CLOSED
LOW OVER NM. MAIN FOCUS FOR PRECIPITATION EXPECTED TO SET UP OVER THE
NORTHERN CWA AFTER MIDNIGHT AS VORT LOBE CONTINUES TO PIVOT NORTH AND
EVENTUALLY NORTHWEST. SEVERE THREAT WILL LINGER THE LONGEST ACROSS
THE NORTHEAST TX PANHANDLE AND EASTERN HALF OF THE OK PANHANDLE...BUT
WILL EVENTUALLY DIMINISH THERE AS WELL LATER TONIGHT AS PACIFIC FRONT
CONTINUES TO PUSH EAST AND STATIONARY FRONT ACROSS NORTHERN CWA
EVENTUALLY PUSHES SOUTHEAST...SQUEEZING THE DEEPER LOW-LEVEL MOISTURE
AND ASSOCIATED INSTABILITY EASTWARD.
KB
PREV DISCUSSION... /ISSUED 634 PM CDT MON APR 2 2012/
UPDATE...
EXPANDED SEVERE THUNDERSTORM WATCH ONE TIER OF COUNTIES WESTWARD.
SURFACE FRONT DRAPED SOUTH/SOUTHWEST ACROSS THE EASTERN OK AND
NORTHEAST TEXAS PANHANDLE...AND DRYLINE EXTENDING SOUTH FROM THE
FRONT ACROSS THE EASTERN TX PANHANDLE...WERE RETREATING TO THE WEST
AND NORTHWEST IN RESPONSE TO SURFACE LOW DEVELOPING NORTHEAST INTO
THE TX PANHANDLE AHEAD OF STRONG MID-LEVEL VORT MAX PIVOTING AROUND
CLOSED MID/UPPER-LEVEL LOW OVER NM. LATEST RUC GUIDANCE SHOWS THIS
BOUNDARY WILL CONTINUE TO RETREAT A LITTLE FARTHER EARLY THIS
EVENING...BEFORE DRYLINE ACROSS SOUTHEAST TX PANHANDLE GETS OVERTAKEN
BY PACIFIC FRONT AND SHOVED EASTWARD.
KB
PREV DISCUSSION... /ISSUED 625 PM CDT MON APR 2 2012/
UPDATE...
CONVECTION WILL CONTINUE TO DEVELOP IN RESPONSE TO A COLD FRONT
ACROSS THE PANHANDLES AND APPROACHING UPPER LOW FROM NEW MEXICO. THIS
CONVECTION WILL AFFECT ALL OF THE TAF SITES THROUGH 10Z TUESDAY. VFR
CONDITIONS WILL PREVAIL EXCEPT MVFR TO POSSIBLY IFR CONDITIONS IN AND
NEAR THE CONVECTION. WINDS WILL BECOME NORTHERLY TO NORTHEASTERLY 15
AND 20 TO 25 AND 30 KNOTS WITH HIGHER GUSTS BEHIND THE COLD
FRONT...WITH SOUTHERLY TO SOUTHWESTERLY WINDS AHEAD OF THE FRONT
MAINLY THIS EVENING AT THE AMARILLO TAF SITE.
SCHNEIDER
PREV DISCUSSION... /ISSUED 336 PM CDT MON APR 2 2012/
DISCUSSION...
UPPER LEVEL LOW HAS CUTOFF FROM THE FLOW OVER CENTRAL NEW
MEXICO. THIS LOW IS EXPECTED TO SLOWLY LIFT NORTHEAST THROUGH
NORTHEAST NEW MEXICO AND ACROSS THE NORTHWEST PART OF OUR
CWA INTO SOUTHWEST KANSAS BY WEDNESDAY AFTERNOON. A SURFACE
COLD FRONT HAS STALLED NEAR THE CANADIAN RIVER VALLEY THIS
AFTERNOON. THIS FRONT MAY LIFT BACK TO THE NORTH BRIEFLY
THIS EVENING BEFORE MOVE SOUTHEAST AGAIN LATER TONIGHT. THE
COLD FRONT WILL THEN STALL AGAIN BY TUESDAY AFTERNOON ACROSS
THE FAR SOUTHEAST TEXAS PANHANDLE BEFORE MOVING SOUTH OF THE
TEXAS PANHANDLE BY TUESDAY EVENING.
WILL KEEP THE NORTHWEST CWA UNDER A WIND ADVISORY THROUGH
THE MID EVENING AS WINDS ARE EXPECTED TO PICK UP AGAIN BY
EARLY THIS EVENING AS ANOTHER SURGE OF COLDER AIR MOVES
SOUTH. SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE ACROSS THE
EASTERN CWA ALONG A DRYLINE AND THEN THE BEST CHANCE OF SHOWERS AND
STORMS WILL BE ALONG AND BEHIND THE COLD FRONT ACROSS THE NORTHERN
CWA. THIS UPPER LEVEL LOW WILL HAVE SEVERAL SPOKES OF VORTICITY
ROTATING AROUND IT AS WELL...SO THE SHOWER AND THUNDERSTORM
POTENTIAL WILL PICK UP EACH TIME ONE THESE MOVES OVER THE REGION.
ON TUESDAY...WILL KEEP THE SHOWERS AND THUNDERSTORMS GOING AS THE
COLD CORE OF THE LOW MOVES OVER THE PANHANDLES. FORECAST SOUNDINGS
DO SHOW SOME INSTABILITY ON TUESDAY. PRECIPITATION CHANCES DECREASE
FROM SOUTHWEST TO NORTHEAST TUESDAY NIGHT INTO WEDNESDAY MORNING AS
THE UPPER LOW MOVES AWAY.
UPPER LEVEL SHORT WAVE RIDGING TAKES OVER THE HIGH PLAINS
WEDNESDAY NIGHT THROUGH THURSDAY NIGHT AHEAD OF ANOTHER LARGE UPPER
LEVEL TROUGH MOVING INTO THE PACIFIC NORTHWEST.
A DRYLINE IS EXPECTED TO MOVE TO THE EASTERN CWA BY FRIDAY
AFTERNOON. THIS DRYLINE WILL HOLD IN THE EASTERN CWA FRIDAY NIGHT AS
THE WIND SHEAR ALOFT INCREASES AS THE UPPER TROUGH MOVES ACROSS THE
NORTHERN HIGH PLAINS. THE INCREASED WIND SHEAR AND INSTABILITY MAY
LEAD TO THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS ACROSS THE
EASTERN CWA FRIDAY NIGHT...SO HAVE ADDED SOME SLIGHT CHANCE POPS
FOR NOW.
A COLD FRONT MOVES SOUTH ACROSS THE CWA ON SATURDAY NIGHT...COOLING
SUNDAY/S HIGHS BACK 10 TO 15 DEGREES.
FIRE WEATHER...
WILL CONTINUE TO HOLD ONTO THE RED FLAG WARNING FOR THE
SOUTHWEST AND SOUTH CENTRAL TEXAS PANHANDLE THROUGH EARLY
THIS EVENING. SOUTHWEST WINDS SHOULD INCREASE THROUGH THE
REST OF THE AFTERNOON INTO EARLY THIS EVENING AS A SURFACE
LOW INTENSIFIES OVER THE CENTRAL TEXAS PANHANDLE. THE WINDS
WILL THEN PICK UP BEHIND A COLD FRONT TONIGHT...ESPECIALLY
ACROSS THE NORTHWEST CWA...BUT RELATIVE HUMIDITIES WILL BE
ABOVE 20 PERCENT. THE CHANCES OF RAIN INCREASE TONIGHT THROUGH
TUESDAY.
&&
.AMA WATCHES/WARNINGS/ADVISORIES...
TX...WIND ADVISORY UNTIL 4 AM CDT TUESDAY FOR THE FOLLOWING ZONES:
DALLAM...HARTLEY...SHERMAN.
OK...WIND ADVISORY UNTIL 4 AM CDT TUESDAY FOR THE FOLLOWING ZONES:
CIMARRON...TEXAS.
&&
$$
11/08
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1048 PM CDT WED APR 4 2012
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND THURSDAY.
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW HIGH PRESSURE
CENTERED OVER NORTHERN MANITOBA WITH A RIDGE AXIS EXTENDING SOUTH
OVER THE WESTERN GREAT LAKES. ONLY THIN CIRRUS IS PREVENTING A
CLEAR DAY ACROSS THE FORECAST AREA THIS AFTERNOON. PRETTY QUIET
UPSTREAM AS WELL...THANKS TO A BLOCKING MID-LEVEL RIDGE CENTERED
OVER THE NORTHERN PLAINS AND CENTRAL CANADA. SOME COLDER AIR AND
STRATO-CU ARE WORKING SE OVER EASTERN LAKE SUPERIOR...BUT SHOW NO
SIGNS OF PUSHING WESTWARD DESPITE THE COLD ADVECTION. WITH A
SEASONABLE BUT DRY AIRMASS IN PLACE...LOW TEMPS TONIGHT AND
HUMIDITIES TOMORROW ARE THE MAIN FORECAST CONCERNS.
TONIGHT...HUDSON BAY HIGH PRESSURE WILL BE BUILDING SOUTHEAST ACROSS
NORTHERN ONTARIO AND NOSING SOUTHWARD ACROSS THE NORTHERN GREAT
LAKES. THE AIRMASS IS NOT ALL THAT DIFFERENT COMPARED TO LAST
NIGHT...THOUGH WE ARE STARTING OUT A TAD DRIER OVER CENTRAL AND
NORTHEAST WISCONSIN COMPARED TO THIS TIME YESTERDAY AFTERNOON.
1000-850MB WIND SPEEDS WILL BE SLIGHTLY LOWER OVER N-C WISCONSIN
THAN LAST NIGHT...WHICH SHOULD LEAD TO DECOUPLING. NORTHEAST
WISCONSIN WILL CONTINUE TO HAVE NE WINDS FUNNELED DOWN THE BAY AND
ONSHORE ALONG THE LAKE MICHIGAN SHORELINE. THIS SHOULD KEEP THE BL
OVER NE WISCONSIN MIXY ENOUGH TO PREVENT TEMPS FROM FALLING TO
FREEZE WARNING CRITERIA (28F AND BELOW). BUT DO EXPECT TEMPS TO BE
A DEGREE OR TWO COOLER THAN LAST NIGHT DUE TO SUBTLE LOW LEVEL COLD
ADVECTION AND SLIGHTLY DRIER AIR AT THE SURFACE. AS A
RESULT...FORECAST MIN TEMPS SUGGEST THE INHERITED FREEZE WARNING
HEADLINES DO NOT NEED TO BE EXPANDED FURTHER EAST THAN CURRENTLY
COMPRISED...SO WILL LEAVE HEADLINES BE. LOWS RANGING FROM THE LOWER
20S NORTH TO LOWER 30S SOUTHEAST.
THURSDAY...SURFACE RIDGE AXIS WILL REMAIN CENTERED ACROSS EASTERN
WISCONSIN. THE AIRMASS CHANGES LITTLE TOMORROW...THOUGH IS SLIGHTLY
COLDER DUE TO THE COLD ADVECTION FROM TONIGHTS PERIOD. NORTHEAST
WINDS WILL CONTINUE TO KEEP NE WISCONSIN COOLER THAN CENTRAL
WISCONSIN...AND HIGHS WILL RANGE FROM THE MID 50S WEST TO THE MIDDLE
40S EAST. HUMIDITY LEVELS WILL AGAIN FALL SLIGHTLY BELOW CRITICAL
CRITERIA OVER NORTH-CENTRAL WISCONSIN...WITH COOLER AIR OFFSETTING
LOWER DEWPOINTS IN THE AFTERNOON.
.LONG TERM...THURSDAY NIGHT THROUGH NEXT WEDNESDAY...MAIN FCST CONCERNS
ARE THE POTENTIAL FOR FROST/FREEZE CONDITIONS ON THURSDAY NIGHT...CONTINUED
VERY DRY CONDITIONS CONTRIBUTING TO HIGH FIRE DANGER ON FRIDAY...AND
PCPN CHANCES LATER SATURDAY INTO SATURDAY NIGHT.
A HUDSON BAY HIGH WILL BRING VERY DRY CONDITIONS TO THE REGION THROUGH
FRIDAY. CLEAR SKIES AND LIGHT WINDS WILL ALLOW TEMPS TO PLUMMET ON
THURSDAY NIGHT...LEADING TO ANOTHER HARD FREEZE FOR AREAS WEST OF THE
FOX VALLEY AND LAKESHORE. WILL KEEP THE CURRENT AREAL COVERAGE FOR THE
FREEZE WATCH...BUT IT MAY NEED TO BE EXPANDED WITH SUBSEQUENT FCSTS...
ESPECIALLY INTO SOUTHERN MARINETTE AND OCONTO COUNTIES.
ON FRIDAY...MIXING THROUGH 850 MB SUPPORTS HIGH TEMPS IN THE MID TO
UPPER 50S AWAY FROM THE LAKE. DEW POINTS SHOULD CRASH INTO THE TEENS
AND LOWER 20S IN THE SANDY SOIL AREAS...LEADING TO ANOTHER DAY WITH
RELATIVE HUMIDITY IN THE 15-25 PERCENT RANGE. THIS WILL CONTRIBUTE
TO ANOTHER DAY OF HIGH FIRE DANGER.
TEMPERATURES SHOULD CLIMB A BIT ON FRIDAY NIGHT AS THE HIGH SHIFTS
EAST AND WINDS GRADUALLY VEER SOUTH. DID LOWER MIN TEMPS A LITTLE BIT
TO ACCOUNT FOR LINGERING DRY AIR.
A COLD FRONT AND ASSOCIATED UPPER TROF/LOW WILL APPROACH LATER ON
SATURDAY...THEN MOVE THROUGH THE FORECAST AREA SATURDAY NIGHT...
SO HAVE MAINTAINED THE CHC POPS DURING THIS PERIOD. INSTABILITY
PARAMETERS ARE UNIMPRESSIVE...BUT WITH 700-500 MB LAPSE RATES IN
THE 6-7 C/KM RANGE...DECIDED TO KEEP THE MENTION OF ISOLD TSTMS.
ORIGINALLY THOUGHT THAT THE GFS WAS TOO ROBUST AND TOO FAR SOUTH
WITH THE UPPER LOW ARRIVING FROM THE NORTHERN PLAINS LATE IN THE
WEEKEND...BUT THE 12Z ECMWF HAS STRONGLY TRENDED THAT DIRECTION...
AND BRINGS A SLOWLY WEAKENING UPPER LOW THROUGH WI SUNDAY AND
SUNDAY NIGHT. THIS GOES AGAINST THE TRENDS OF MOST MODELS AND
ENSEMBLES...SO WILL KEEP A DRY FCST INTACT FOR NOW. WILL NEED TO
KEEP AN EYE ON THIS FOR SUBSEQUENT FCSTS.
NORTHWEST CANADIAN HIGH PRESSURE WILL BRING DRY WEATHER TO THE
REGION TUESDAY INTO WEDNESDAY.
TEMPERATURES WILL CONTINUE TO AVERAGE NEAR OR A BIT ABOVE NORMAL
THROUGH THE PERIOD.
&&
.AVIATION...VFR WEATHER WITH ONLY SOME HIGH CLOUDS EXPECTED
OVERNIGHT THROUGH THURSDAY.
RDM
&&
.MARINE...A TIGHTENING PRESSURE GRADIENT WILL LEAD TO THE
STRENGTHENING OF NORTHEAST WINDS OVER NORTHERN LAKE MICHIGAN THIS
EVENING. WITH 25-30 KTS AT 950-925MB...INSTABILITY IS MARGINAL FOR
SMALL CRAFT WIND AND WAVES DEVELOPING. WAVES WILL BE INCREASING
INTO THE HIGHER END OF THE 2-4 FT RANGE OVERNIGHT...BUT LOOK TO FALL
SLIGHTLY SHORT OF SMALL CRAFT CRITERIA.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
FREEZE WATCH FROM LATE THURSDAY NIGHT THROUGH FRIDAY MORNING FOR
WIZ005-010>013-018>021-030-031-035>037-045.
FREEZE WARNING FROM 2 AM TO 8 AM CDT THURSDAY FOR WIZ005-010>013-
018>021-030-031-035>037-045.
&&
$$
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
802 PM CDT WED APR 4 2012
UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND THURSDAY.
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW HIGH PRESSURE
CENTERED OVER NORTHERN MANITOBA WITH A RIDGE AXIS EXTENDING SOUTH
OVER THE WESTERN GREAT LAKES. ONLY THIN CIRRUS IS PREVENTING A
CLEAR DAY ACROSS THE FORECAST AREA THIS AFTERNOON. PRETTY QUIET
UPSTREAM AS WELL...THANKS TO A BLOCKING MID-LEVEL RIDGE CENTERED
OVER THE NORTHERN PLAINS AND CENTRAL CANADA. SOME COLDER AIR AND
STRATO-CU ARE WORKING SE OVER EASTERN LAKE SUPERIOR...BUT SHOW NO
SIGNS OF PUSHING WESTWARD DESPITE THE COLD ADVECTION. WITH A
SEASONABLE BUT DRY AIRMASS IN PLACE...LOW TEMPS TONIGHT AND
HUMIDITIES TOMORROW ARE THE MAIN FORECAST CONCERNS.
TONIGHT...HUDSON BAY HIGH PRESSURE WILL BE BUILDING SOUTHEAST ACROSS
NORTHERN ONTARIO AND NOSING SOUTHWARD ACROSS THE NORTHERN GREAT
LAKES. THE AIRMASS IS NOT ALL THAT DIFFERENT COMPARED TO LAST
NIGHT...THOUGH WE ARE STARTING OUT A TAD DRIER OVER CENTRAL AND
NORTHEAST WISCONSIN COMPARED TO THIS TIME YESTERDAY AFTERNOON.
1000-850MB WIND SPEEDS WILL BE SLIGHTLY LOWER OVER N-C WISCONSIN
THAN LAST NIGHT...WHICH SHOULD LEAD TO DECOUPLING. NORTHEAST
WISCONSIN WILL CONTINUE TO HAVE NE WINDS FUNNELED DOWN THE BAY AND
ONSHORE ALONG THE LAKE MICHIGAN SHORELINE. THIS SHOULD KEEP THE BL
OVER NE WISCONSIN MIXY ENOUGH TO PREVENT TEMPS FROM FALLING TO
FREEZE WARNING CRITERIA (28F AND BELOW). BUT DO EXPECT TEMPS TO BE
A DEGREE OR TWO COOLER THAN LAST NIGHT DUE TO SUBTLE LOW LEVEL COLD
ADVECTION AND SLIGHTLY DRIER AIR AT THE SURFACE. AS A
RESULT...FORECAST MIN TEMPS SUGGEST THE INHERITED FREEZE WARNING
HEADLINES DO NOT NEED TO BE EXPANDED FURTHER EAST THAN CURRENTLY
COMPRISED...SO WILL LEAVE HEADLINES BE. LOWS RANGING FROM THE LOWER
20S NORTH TO LOWER 30S SOUTHEAST.
THURSDAY...SURFACE RIDGE AXIS WILL REMAIN CENTERED ACROSS EASTERN
WISCONSIN. THE AIRMASS CHANGES LITTLE TOMORROW...THOUGH IS SLIGHTLY
COLDER DUE TO THE COLD ADVECTION FROM TONIGHTS PERIOD. NORTHEAST
WINDS WILL CONTINUE TO KEEP NE WISCONSIN COOLER THAN CENTRAL
WISCONSIN...AND HIGHS WILL RANGE FROM THE MID 50S WEST TO THE MIDDLE
40S EAST. HUMIDITY LEVELS WILL AGAIN FALL SLIGHTLY BELOW CRITICAL
CRITERIA OVER NORTH-CENTRAL WISCONSIN...WITH COOLER AIR OFFSETTING
LOWER DEWPOINTS IN THE AFTERNOON.
.LONG TERM...THURSDAY NIGHT THROUGH NEXT WEDNESDAY...MAIN FCST CONCERNS
ARE THE POTENTIAL FOR FROST/FREEZE CONDITIONS ON THURSDAY NIGHT...CONTINUED
VERY DRY CONDITIONS CONTRIBUTING TO HIGH FIRE DANGER ON FRIDAY...AND
PCPN CHANCES LATER SATURDAY INTO SATURDAY NIGHT.
A HUDSON BAY HIGH WILL BRING VERY DRY CONDITIONS TO THE REGION THROUGH
FRIDAY. CLEAR SKIES AND LIGHT WINDS WILL ALLOW TEMPS TO PLUMMET ON
THURSDAY NIGHT...LEADING TO ANOTHER HARD FREEZE FOR AREAS WEST OF THE
FOX VALLEY AND LAKESHORE. WILL KEEP THE CURRENT AREAL COVERAGE FOR THE
FREEZE WATCH...BUT IT MAY NEED TO BE EXPANDED WITH SUBSEQUENT FCSTS...
ESPECIALLY INTO SOUTHERN MARINETTE AND OCONTO COUNTIES.
ON FRIDAY...MIXING THROUGH 850 MB SUPPORTS HIGH TEMPS IN THE MID TO
UPPER 50S AWAY FROM THE LAKE. DEW POINTS SHOULD CRASH INTO THE TEENS
AND LOWER 20S IN THE SANDY SOIL AREAS...LEADING TO ANOTHER DAY WITH
RELATIVE HUMIDITY IN THE 15-25 PERCENT RANGE. THIS WILL CONTRIBUTE
TO ANOTHER DAY OF HIGH FIRE DANGER.
TEMPERATURES SHOULD CLIMB A BIT ON FRIDAY NIGHT AS THE HIGH SHIFTS
EAST AND WINDS GRADUALLY VEER SOUTH. DID LOWER MIN TEMPS A LITTLE BIT
TO ACCOUNT FOR LINGERING DRY AIR.
A COLD FRONT AND ASSOCIATED UPPER TROF/LOW WILL APPROACH LATER ON
SATURDAY...THEN MOVE THROUGH THE FORECAST AREA SATURDAY NIGHT...
SO HAVE MAINTAINED THE CHC POPS DURING THIS PERIOD. INSTABILITY
PARAMETERS ARE UNIMPRESSIVE...BUT WITH 700-500 MB LAPSE RATES IN
THE 6-7 C/KM RANGE...DECIDED TO KEEP THE MENTION OF ISOLD TSTMS.
ORIGINALLY THOUGHT THAT THE GFS WAS TOO ROBUST AND TOO FAR SOUTH
WITH THE UPPER LOW ARRIVING FROM THE NORTHERN PLAINS LATE IN THE
WEEKEND...BUT THE 12Z ECMWF HAS STRONGLY TRENDED THAT DIRECTION...
AND BRINGS A SLOWLY WEAKENING UPPER LOW THROUGH WI SUNDAY AND
SUNDAY NIGHT. THIS GOES AGAINST THE TRENDS OF MOST MODELS AND
ENSEMBLES...SO WILL KEEP A DRY FCST INTACT FOR NOW. WILL NEED TO
KEEP AN EYE ON THIS FOR SUBSEQUENT FCSTS.
NORTHWEST CANADIAN HIGH PRESSURE WILL BRING DRY WEATHER TO THE
REGION TUESDAY INTO WEDNESDAY.
TEMPERATURES WILL CONTINUE TO AVERAGE NEAR OR A BIT ABOVE NORMAL
THROUGH THE PERIOD.
&&
.AVIATION...VFR WEATHER WITH ONLY SOME HIGH CLOUDS EXPECTED
TONIGHT AND THURSDAY.
RDM
&&
.MARINE...A TIGHTENING PRESSURE GRADIENT WILL LEAD TO THE
STRENGTHENING OF NORTHEAST WINDS OVER NORTHERN LAKE MICHIGAN THIS
EVENING. WITH 25-30 KTS AT 950-925MB...INSTABILITY IS MARGINAL FOR
SMALL CRAFT WIND AND WAVES DEVELOPING. WAVES WILL BE INCREASING
INTO THE HIGHER END OF THE 2-4 FT RANGE OVERNIGHT...BUT LOOK TO FALL
SLIGHTLY SHORT OF SMALL CRAFT CRITERIA.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
FREEZE WATCH FROM LATE THURSDAY NIGHT THROUGH FRIDAY MORNING FOR
WIZ005-010>013-018>021-030-031-035>037-045.
FREEZE WARNING FROM 2 AM TO 8 AM CDT THURSDAY FOR WIZ005-010>013-
018>021-030-031-035>037-045.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
611 PM CDT WED APR 4 2012
.SHORT TERM...TONIGHT THROUGH SATURDAY
318 PM CDT WED APR 4 2012
MAIN EMPHASIS OF FORECAST WILL BE ON FREEZE CONDITIONS THE NEXT
COUPLE OF NIGHTS ALONG WITH LOW DAYTIME RELATIVE LEVELS THURSDAY
AND FRIDAY.
WATER VAPOR IMAGERY AND RUC 500MB ANALYSIS SHOW A HIGHLY AMPLIFIED
MID-LEVEL RIDGE IN PLACE FROM THE NORTHERN PLAINS INTO MANITOBA AND
HUDSON BAY. MEANWHILE...A CLOSED/CUTOFF LOW WAS SLOWLY MOVING EAST
INTO OKLAHOMA. AT THE SURFACE...HIGH PRESSURE WAS CENTERED OVER
WESTERN ONTARIO. DRY/COOL NORTHEAST FLOW WAS RESULTING ACROSS THE
AREA TODAY UNDER SUNNY SKIES WITH TEMPERATURES IN THE UPPER 50S TO
MIDDLE 60S AND DEWPOINTS WAY DOWN IN THE 20S.
04.12Z NAM/GFS SHOWING GOOD AGREEMENT THROUGH FRIDAY...BUT THEN SOME
DIFFERENCES REGARDING THE STRENGTH OF THE MID-LEVEL TROUGH AND
SURFACE COLD FRONT CROP UP SATURDAY. THE 04.09Z SREF WAS GENERALLY
USED FOR THIS TIME FRAME.
FOR TONIGHT THE MAIN STORY WILL BE CLEAR/DRY CONDITIONS LEADING TO A
RAPID DROP OFF IN TEMPERATURES. WITH THE RIDGE AXIS BUILDING
SOUTHWARD INTO THE REGION...LOOKS LIKE WINDS WILL TAPER OFF TO LESS
THAN 5 MPH MOST PLACES WHICH WILL ALLOW TEMPERATURES TO FALL OFF
INTO THE MIDDLE 20S TO MIDDLE 30S. PLAN ON THE COLDEST AIR TO BE
OVER THE FAVORED COLD SPOTS ALONG/NORTH OF THE I-94 CORRIDOR. AS
SUCH...WILL KEEP FREEZE WARNING HOISTED FOR THIS AREA FROM 2 AM
THROUGH 8 AM THURSDAY.
HIGH PRESSURE WILL CONTINUE TO BE THE DOMINATING WEATHER FEATURE
THROUGH FRIDAY WITH PREVAILING DRY CONDITIONS. CONCERN WILL
AGAIN BE ON THE NEED FOR FREEZE HEADLINES LATE THURSDAY NIGHT INTO
FRIDAY MORNING WITH LOWS DIPPING AGAIN INTO THE MIDDLE 20S AND LOWER
30S ACROSS MUCH OF THE AREA...WITH MID/UPPER 20S MORE PREVALENT EAST
OF THE MISSISSIPPI RIVER. WITH THIS IN MIND...WILL BE EXPANDING THE
FREEZE WATCH TO INCLUDE ALL OF THE AREA. SEE WWA SECTION BELOW AND
LATEST FREEZE WATCH STATEMENT FOR DETAILS.
RIDGE STARTS TO BREAK DOWN/MOVE EAST LATE FRIDAY NIGHT THROUGH
SATURDAY AS A FAIRLY VIGOROUS MID-LEVEL TROUGH PUSHES EAST INTO THE
NORTHERN PLAINS/UPPER MISSISSIPPI RIVER REGION. AS STATED
ABOVE...GFS AND NAM ARE DIFFERING AS TO THE STRENGTH OF THIS WAVE
WITH THE GFS LOOKING A BIT STRONGER. THIS HAS A BEARING ON SURFACE
COLD FRONT STRENGTH AND AMOUNT OF MOISTURE TRANSPORT NORTHWARD INTO
THE AREA FOR THE PRODUCTION OF SHOWERS. WITH THIS IN MIND...WILL
MOVE IN 20-30 PERCENT CHANCE OF SHOWERS TO ABOUT THE MISSISSIPPI
RIVER THROUGH FRIDAY MORNING...INCREASING/EXPANDING TO 40 PERCENT
CHANCE OF SHOWERS/ISOLATED THUNDER SATURDAY AFTERNOON ACROSS THE
ENTIRE AREA.
SHOWERS WILL LINGER INTO SATURDAY EVENING...THEN EXIT WITH THE COLD
FRONTAL PASSAGE AFTER MIDNIGHT.
AS FAR AS DAYTIME HIGH TEMPERATURES THURSDAY THROUGH SATURDAY...PLAN
ON 50S THURSDAY AND FRIDAY...WARMING SOME INTO THE UPPER 50S TO
LOWER 60S ON SATURDAY.
.LONG TERM...SUNDAY THROUGH WEDNESDAY
318 PM CDT WED APR 4 2012
04.12Z GFS AND 04.00Z ECMWF IN OVERALL GOOD AGREEMENT THROUGH THE
LONG TERM PERIOD WITH OVERALL DRY/COOLER CONDITIONS. BOTH MODELS SHOW THE AREA
IN BREEZY DRYING WESTERLY FLOW DURING THE DAY SUNDAY IN THE WAKE OF
THE COLD FRONT AND LOW PASSING THROUGH SOUTHERN ONTARIO CANADA.
BREEZY/COOLER NORTHWEST FLOW INVADES THE AREA MONDAY THROUGH TUESDAY
AS HIGH PRESSURE BUILDS SOUTHWARD INTO THE PLAINS/UPPER MISSISSIPPI
RIVER REGION AND DEEP LOW PRESSURE ANCHORS OVER QUEBEC. SOME WARMING
THEN EXPECTED ON WEDNESDAY AS THE AXIS OF THE SURFACE RIDGE SHIFTS
EAST OF THE REGION AND HEIGHTS BUILD ALOFT. TEMPERATURE-WISE...LOOK
FOR HIGHS IN THE MID-UPPER 50S SUNDAY...COOLING INTO THE UPPER 40S
TO LOWER 50S MONDAY/TUESDAY...AND THEN BACK INTO THE MID-UPPER 50S
WEDNESDAY.
&&
.AVIATION...TONIGHT AND THURSDAY
611 PM CDT WED APR 4 2012
VFR CONDITIONS THROUGHOUT PERIOD AS HIGH PRESSURE ACROSS SOUTHERN
CANADA DOMINATES. UPPER-LEVEL LOW OVER CENTRAL PLAINS WILL CONTINUE
TO SPILL HIGH CIRRUS OVER TAF SITES. WINDS WILL REMAIN FROM THE NORTHEAST
AROUND 10 KTS...AND DURING DAYTIME MIXING GUSTS BETWEEN 16-18 KTS
ARE LIKELY. AT NIGHT...DECOUPLING WILL LEAD TO WINDS 4-7 KTS.
&&
.FIRE WEATHER...THURSDAY THROUGH FRIDAY
318 PM CDT WED APR 4 2012
HUDSON BAY HIGH WILL PUMP A VERY DRY AIRMASS INTO THE REGION
THURSDAY THROUGH FRIDAY. LOOK FOR AFTERNOON MINIMUM RH READINGS IN THE
20-25 PERCENT RANGE THURSDAY...MODERATING A FEW PERCENTAGE POINTS
INTO THE MID 20S FRIDAY AFTERNOON. WINDS LOOK GENERALLY ON THE
LIGHTER SIDE THURSDAY OUT OF THE EAST SOMEWHERE IN THE 5-12 MPH
RANGE WITH SOME GUSTS AROUND 15 MPH. WINDS ARE THEN EXPECTED TO
INCREASE OUT OF THE SOUTHEAST ON FRIDAY...ESPECIALLY WEST OF THE
MISSISSIPPI RIVER FRIDAY AS THE HIGH BEGINS TO PUSH EAST INTO THE
GREAT LAKES REGION.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
318 PM CDT WED APR 4 2012
WI...FREEZE WATCH FROM LATE THURSDAY NIGHT THROUGH FRIDAY MORNING FOR
WIZ017-029-032>034-041>044-053>055-061.
FREEZE WARNING FROM 2 AM TO 8 AM CDT THURSDAY FOR WIZ017-029-034-
042>044.
MN...FREEZE WATCH FROM LATE THURSDAY NIGHT THROUGH FRIDAY MORNING FOR
MNZ079-086>088-094>096.
IA...FREEZE WATCH FROM LATE THURSDAY NIGHT THROUGH FRIDAY MORNING FOR
IAZ008>011-018-019-029-030.
&&
$$
SHORT TERM...DAS
LONG TERM....DAS
AVIATION...ZT
FIRE WEATHER...DAS
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1141 AM CDT TUE APR 3 2012
.UPDATE...
THE THREAT FOR THUNDERSTORMS HAS DIMINISHED IN SOUTHEAST WI UNTIL
MID AFTERNOON. THE OUTFLOW BOUNDARY THAT CAUSED SCATTERED TO
ISOLATED THUNDERSTORM DEVELOPMENT WEAKENED AND SHIFTED INTO
NORTHEAST IL. THE LINE OF MID CLOUDS...ACCAS...STRETCHING THROUGH
SAUK...DODGE...FOND DU LAC AND SHEBOYGAN COUNTIES IS DUE TO WEAK
CONVERGENCE ALONG THE 850MB FRONT. RUC SNDGS FOR OSHKOSH SHOW
ELEVATED CAPE OVER 500 J/KG WITH A LARGE AREA OF THAT IN THE HAIL
GROWTH ZONE. THE INSTABILITY DOES NOT TRANSLATE DOWN TO MADISON BUT
IT IS BETTER IN MKE EARLY THIS AFTERNOON ACCORDING TO THE RUC. THE
NAM STILL SHOWS SOME LIMITED ELEVATED CAPE FOR MSN AND MKE THROUGH
THE AFTERNOON UNTIL THE 850MB WARM FRONT GETS SOUTH OF WI.
IT LOOKS LIKE THERE WILL BE A FAIRLY NARROW WINDOW OF OPPORTUNITY TO
POP A THUNDERSTORM AND IT SHOULD BE AROUND THIS 850MB CONVERGENCE
BOUNDARY. THE BOUNDARY WILL SLOWLY SINK SOUTHWARD THIS
AFTERNOON...EXITING SOUTHEAST WI AROUND 00Z.
EXPECTING THE STRATUS CURRENTLY OVER NORTHERN WI...WHICH SEEMS TIED
TO MAINLY 700MB DEFORMATION...TO SLIP SOUTHWARD THIS AFTERNOON AS
THE SFC LOW TRACKS ACROSS NORTHERN IL. THIS TRANSLATION MAY NOT
EXACTLY BE LINEAR AND THE STRATUS MAY NEVER REACH FAR SOUTHEAST WI
BY 00Z AS THE 700MB DEFORMATION ZONE IS EXPECTED TO STALL JUST SHORT
OF THE WI/IL BORDER. AT SOME POINT BETWEEN LATE THIS AFTERNOON AND
EVENING...EXPECTING SE WI TO FILL IN WITH SOME STRATUS. THE NAM
SHOWS STRATUS EXITING AT OR SHORTLY AFTER 00Z...BUT THIS MAY BE TOO
QUICK.
WITH THE SFC WINDS ALREADY CHANGED OVER TO NORTH IN THE WESTERN
FORECAST AREA. THERE WILL STILL BE SOME WARMING DUE TO THE PLENTIFUL
SUNSHINE...BUT WILL NEED TO ADJUST MAX TEMPS DOWN A
NOTCH...ESPECIALLY IN NORTHERN AND SOUTHERN FORECAST AREAS.
&&
.AVIATION/18Z TAFS/...
VFR CONDITIONS EXPECTED THROUGH THE PERIOD....WITH COLD ADVECTION
STRATUS TO REMAIN IN THE 3500-4000 FT RANGE. THE STRATUS CLOUDS
WILL BE SLOW TO ARRIVE LATE THIS AFTERNOON AND MAY NOT GET TO
SOUTHEAST WI UNTIL EARLY THIS EVENING. EASTERLY WINDS WILL SHIFT
TO THE NORTH- NORTHEAST LATE THIS MORNING AND INCREASE TO 10 TO 15
KNOTS WITH GUSTS TO 20 TO 25 KNOTS THIS AFTERNOON AS SURFACE LOW
PASSES TO THE SOUTH.
VERY ISOLATED CHANCE FOR THUNDERSTORMS AS THE UPPER LEVEL FRONT
SINKS SOUTHWARD THIS AFTERNOON. LEFT CHANCE FOR ANY PRECIP OUT OF
TAFS.
&&
.PREV DISCUSSION... /ISSUED 408 AM CDT TUE APR 3 2012/
SHORT TERM...TODAY AND TONIGHT. FORECAST CONFIDENCE MEDIUM.
ELEVATED THUNDERSTORMS THAT DEVELOPED OVER MSP EARLIER IN REGION OF
STRONG LAYER FRONTOGENETIC FORCING ON NOSE OF S-SW 30-45 KT 850 MB
WINDS IMPINGING ON BAROCLINIC ZONE DRAPED ACROSS NRN/CENTRAL WI.
FORCING WEAKENS AS THESE WINDS WEAKEN AND VEER TO THE WEST WITH THE
BEST CROSS-ISOTHERM FLOW SHIFTING EAST OF STATE BY 12Z. THIS SHIFT
NOTED WITH LATEST DEVELOPMENT TO THE EAST OVER LAKE MICHIGAN...IN
LINE WITH RUC AND OTHER SHORT TERM MODEL GUIDANCE.
HAVE BACKED OFF POPS FOR THE ENTIRE CWA THIS MORNING...BUT COULD NOT
DROP COMPLETELY THIS AFTERNOON AS COULD SEE A FEW LIGHT RAIN SHOWERS
WITH CONVERGENCE ALONG BAROCLINIC ZONE AS IT MOVES SOUTH THROUGH
CWA THIS AFTERNOON. SOME ELEVATED CAPE WITH BOUNDARY...BUT FORECAST
SOUNDINGS SHOW A CAP BETWEEN 800 MB AND 700 MB SO WILL ONLY MENTION
ISOLATED THUNDER.
HIGHS TO BE REACHED LATE MORNING/EARLY AFTERNOON THEN DROP WITH COLD
AIR ADVECTION WITH DEVELOPING NORTH TO NORTHEAST WINDS. 925MB TEMPS
SUPPORT HIGHS IN THE MID TO UPPER 60S SOUTH AND SOUTHWEST...WITH MID
UPPER 50S NORTHEAST.
CLEARING FROM NORTH TO SOUTH OVERNIGHT...THOUGH A FEW CLOUDS MAY
LINGER IN THE FAR SOUTH. COLD ADVECTION CONTINUES WITH LOWS DIPPING
INTO THE MID 30S NORTH...AND UPPER 30S TO AROUND 40 IN THE SOUTH BY
MORNING. COULD SEE SOME PATCHY FROST IN THE NORTH...BUT NOT
EXPECTING ENOUGH TO MENTION FOR NOW.
WEDNESDAY THROUGH FRIDAY...FORECAST CONFIDENCE...MEDIUM TO HIGH
SFC HIGH PRESSURE CENTERED JUST TO THE NORTH OF MINNESOTA WEDNESDAY
MORNING WILL MEANDER SOUTHEAST TO MICHIGAN BY FRIDAY.
MEANWHILE...UPPER RIDGING WILL BUILD BACK INTO THE AREA BEHIND
EXITING UPPER LOW TO THE SOUTH. OVERALL...LOOKS LIKE A VERY DRY
AIRMASS ACROSS SOUTHERN WISCONSIN FOR THE SECOND HALF OF THE WORK
WEEK. NO PRECIP CURRENTLY EXPECTED...WITH ONLY PASSING HIGH CLOUDS
AT TIMES.
THOUGH SKIES WILL BE MOSTLY SUNNY...MODELS ARE INDICATING A PUSH OF
COLDER AIR INTO THE STATE FROM THE NORTHEAST WEDNESDAY NIGHT INTO
THURSDAY. IN ADDITION...PERSISTENT EASTERLY WINDS WILL KEEP CHILLY
AIR COMING IN OFF THE LAKE. EVEN SO...HIGH TEMPERATURES WILL
STILL BE NEAR NORMAL FOR EARLY APRIL...EVEN A BIT ABOVE NORMAL
WEDNESDAY AND FRIDAY AWAY FROM THE LAKE. MAY SEE SOME FROST WITH
LOWS TEMPS MORE TOWARD NORMAL...PARTICULARLY THU NIGHT WHEN THE
WINDS WILL BE FAIRLY LIGHT.
SATURDAY THROUGH MONDAY...FORECAST CONFIDENCE...MEDIUM
MODELS SHOWING A PAIR OF WAVES TO SLIDE THROUGH SAT/SAT NIGHT AND
SUN NIGHT/MONDAY. ENOUGH CONFIDENCE TO KEEP SOME POPS GOING. LOOKS
LIKE HIGH TEMPS WILL BE 5 TO 10 DEGREES ABOVE NORMAL THROUGH THE
WEEKEND AND POSSIBLY INTO EARLY NEXT WEEK. WESTERLY LOW LEVEL FLOW
MAY EVEN PUSH THE MILDER TEMPS TO THE LAKE...ESPECIALLY IF STRONG
ENOUGH TO OVERCOME THE LAKE BREEZE POTENTIAL THROUGH THE DAY.
AVIATION/12Z TAFS...
CONVECTION HAS DEVELOPED WELL TO THE NORTH AND EAST OF TAF SITES
EARLY THIS MORNING...REDUCING PROSPECTS OF SEEING ANY CONVECTION
TODAY. WILL MONITOR TRENDS OVER THE NEXT FEW HOURS...BUT PLAN IS TO
LEAVE ANY PRECIPITATION OUT OF 12Z TAFS. VFR CONDITIONS EXPECTED
THROUGH THE PERIOD....WITH COLD ADVECTION STRATUS TO REMAIN IN THE
3500-4000 FT RANGE. EASTERLY WINDS WILL SHIFT TO THE NORTH-NORTHEAST
LATE THIS MORNING AND INCREASE TO 10 TO 15 KNOTS WITH GUSTS TO 20 TO
25 KNOTS THIS AFTERNOON AS SURFACE LOW PASSES TO THE SOUTH.
MARINE...
HELD OFF ON A SMALL CRAFT ADVISORY FOR TONIGHT AS WINDS AND WAVES
REMAIN JUST BELOW CRITERIA WITH WINDS EASING A BIT TONIGHT. GRADIENT
TIGHTENS ON WEDNESDAY WITH WAVES BUILDING TO SMALL CRAFT CRITERIA BY
WEDNESDAY NIGHT IN PERSISTENT NORTH-NORTHEAST FLOW. WAVES WILL
REMAIN HIGH INTO THURSDAY...THEN LOWER WITH SHORTER FETCH AS WINDS
VEER TO THE EAST AND EASE.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
UPDATE...MRC
TODAY/TONIGHT AND AVIATION/MARINE...REM
WEDNESDAY THROUGH MONDAY...DDV
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
649 AM CDT TUE APR 3 2012
.UPDATE...
649 AM CDT TUE APR 3 2012
HAVE HAD A FEW SHOWERS AND THUNDERSTORMS POP UP IN THE LAST 45
MINUTES FROM THE DECORAH AREA TO LA CROSSE. THE ONE STORM NEAR
DECORAH ENDED UP PRODUCING PEA SIZE HAIL. THESE APPEAR TO BE ON AN
850MB FRONT. 03.10Z RUC FORECAST SOUNDINGS ON THIS FRONT ARE
HIGHLY UNFAVORABLE FOR PRECIPITATION...AND WITH MOST MODELS NOT
SUGGESTING PRECIPITATION...ONLY GUESS IS THAT THERE MUST BE A
LITTLE MORE MOISTURE AROUND 750MB THAN FORECAST. IF YOU MODIFY A
RUC SOUNDING TO SATURATE 750MB AND COOL THE TEMPERATURE
ACCORDINGLY...UP TO 700 J/KG OF CAPE IS AVAILABLE. HARD TO SAY
EXACTLY HOW LONG THE PRECIPITATION WILL LAST...BUT IF THE
ENVIRONMENT THE RUC SUGGESTS IS MOSTLY CORRECT...THEY WILL HAVE A
HARD TIME LASTING MORE THAN A FEW HOURS. THEREFORE...ONLY HAVE
CHANCES IN UNTIL 14Z.
.SHORT TERM...TODAY THROUGH THURSDAY
349 AM CDT TUE APR 3 2012
MAIN FORECAST CONCERNS ARE ON RAIN CHANCES OVER CENTRAL WISCONSIN
THIS MORNING. FOCUS THEN TURNS TO TEMPERATURES TONIGHT THROUGH
THURSDAY NIGHT...WITH THE POTENTIAL FOR OVERNIGHT LOWS TO FALL
BELOW FREEZING ACROSS PORTIONS OF THE FORECAST AREA.
LATEST SURFACE OBSERVATIONS SHOWED A COLD FRONT EXTENDING FROM
NORTH CENTRAL MINNESOTA THROUGH WESTERN IOWA...MOVING EAST.
CURRENT RADAR INDICATED SHOWERS AND THUNDERSTORMS WERE MOVING
ACROSS NORTH CENTRAL INTO CENTRAL WISCONSIN...NORTH AND EAST OF
THE INTERSTATE 94 CORRIDOR.
THE COLD FRONT WILL PUSH ACROSS THE FORECAST AREA THIS MORNING
INTO EARLY THIS AFTERNOON WITH THE MAIN IMPACT BEING A WIND SHIFT.
IN ADDITION...WINDS WILL SWITCH TO THE NORTH AT 15 TO 20 MPH WITH
GUST TO AROUND 30 MPH POSSIBLE IN THE OPEN AREAS OF SOUTHEAST
MINNESOTA AND NORTHEAST IOWA...AS WELL AS THE RIDGE TOPS OF
WESTERN WISCONSIN. HIGH PRESSURE IS EXPECTED TO GRADUALLY BUILD
INTO THE REGION LATE THIS AFTERNOON INTO TONIGHT...WITH CLOUDS
DECREASING FROM NORTH TO SOUTH. LOOK FOR COOLER AIR TO FILTER
INTO THE REGION TONIGHT. 850 MB TEMPERATURES THIS AFTERNOON WILL
RANGE FROM 14 C ACROSS FAR SOUTHWEST WISCONSIN TO AROUND 4 C OVER
NORTH CENTRAL WISCONSIN. BY EARLY WEDNESDAY MORNING THE 850 MB
TEMPERATURES WILL FALL TO AROUND 0 C ACROSS FAR NORTHERN WISCONSIN
TO AROUND 4 C ACROSS NORTHEAST IOWA. PLAN ON LOWS FALLING INTO THE
LOWER 30S OVER NORTH CENTRAL WISCONSIN TO AROUND 40 ACROSS
NORTHEAST IOWA...UNDER MOSTLY CLEAR SKIES. LIGHT NORTH WINDS AND
VERY DRY AIR ALOFT SHOULD INHIBIT FROST DEVELOPMENT
TONIGHT...DESPITE TEMPERATURES FALLING TO AROUND FREEZING ACROSS
NORTH CENTRAL INTO CENTRAL WISCONSIN. CANNOT RULE OUT LOW LYING
AREAS DECOUPLING AND FALLING BELOW FREEZING TONIGHT...SO WILL HAVE
TO KEEP A CLOSE EYE ON TEMPERATURE TRENDS THIS AFTERNOON INTO THE
EVENING HOURS.
HIGH PRESSURE WILL CONTINUE BUILDING OVER THE AREA ON WEDNESDAY
LEADING TO DRY AND QUIET CONDITIONS. AN UPPER LEVEL LOW IS
EXPECTED TO MOVE FROM THE CENTRAL PLAINS...EAST THROUGH THE MIDDLE
MISSISSIPPI RIVER VALLEY. SHOWERS AND THUNDERSTORMS WILL OCCUR
ACROSS SOUTHERN IOWA THROUGH MISSOURI AND REMAIN WELL SOUTH OF THE
FORECAST AREA. RATHER DRY AIR WILL SETTLE OVER THE AREA ON
WEDNESDAY. AFTERNOON MIXING WILL LEAD TO DEW POINTS FALLING INTO
THE 20S TO THE UPPER TEENS...WITH VERY DRY AIR JUST ABOVE THE
SURFACE. HAVE LOWERED DEW POINTS SIGNIFICANTLY FOR WEDNESDAY
AFTERNOON. PLAN ON HIGHS ON WEDNESDAY RANGING FROM THE MID 50S
ACROSS NORTHERN WISCONSIN TO AROUND 60 OVER NORTHEAST IOWA. LIGHT
WINDS AND MOSTLY CLEAR SKIES WEDNESDAY NIGHT WILL AGAIN LEAD TO
FROST/FREEZING CONCERNS. PLAN ON LOW TEMPERATURES FALLING INTO THE
UPPER 20S ACROSS NORTH CENTRAL AND CENTRAL WISCONSIN. TEMPERATURES
WILL FALL INTO THE LOWER 30S ALONG THE MISSISSIPPI RIVER WESTWARD
THROUGH SOUTHEAST MINNESOTA INTO NORTHEAST IOWA. FREEZE HEADLINES
MAY BE NEEDED IN CENTRAL AND NORTH CENTRAL WISCONSIN. FROST
DEVELOPMENT IS IN QUESTION GIVEN THE VERY DRY AIR OVER THE AREA
AND LIGHT NORTHEAST WINDS. AT THIS TIME FROST WIDESPREAD FROST
FORMATION IS NOT ANTICIPATED BUT TEMPERATURES FALLING BELOW
FREEZING COULD DAMAGE COLD SENSITIVE PLANTS. FAVORED COLD AIR
DRAINAGE LOCATIONS ACROSS FAR WESTERN AND SOUTHWEST WISCONSIN
COULD ALSO BE AT RISK OF SEEING THESE COLD TEMPERATURES.
THE HIGH IS EXPECTED TO PERSIST THURSDAY INTO THURSDAY NIGHT...WITH
THE CENTER OF THE HIGH BACKING INTO CENTRAL AND NORTHEAST WISCONSIN.
850 MB TEMPERATURES REALLY FALL ON THURSDAY...WITH FORECAST MODELS
SHOWING TEMPERATURES RANGING FROM -4 C OVER NORTHEAST WISCONSIN TO
AROUND 2 C OVER NORTHEAST IOWA. PLAN ON HIGH TEMPERATURES RANGING
FROM THE LOWER 50S ACROSS NORTH CENTRAL WISCONSIN TO THE MID 50S
OVER NORTHEAST IOWA INTO FAR SOUTHWEST WISCONSIN UNDER SUNNY SKIES.
HAVE LOWERED DEW POINTS AGAIN FOR THURSDAY AFTERNOON DURING THE
MAXIMUM MIXING. CLEAR SKIES AND LIGHT WINDS WILL ALLOW TEMPERATURES
TO PLUMMET THURSDAY NIGHT. THERE WILL ONCE AGAIN BE THE CONCERN FOR
FREEZING TEMPERATURES ACROSS MUCH OF THE FORECAST AREA WITH LOWS
RANGING FROM THE LOWER 30S ACROSS NORTH CENTRAL WISCONSIN TO THE MID
30S OVER PORTIONS OF NORTHEAST IOWA. FREEZE HEADLINES MAY BE NEEDED
ONCE AGAIN THURSDAY NIGHT.
.LONG TERM...FRIDAY THROUGH MONDAY
349 AM CDT TUE APR 3 2012
03.00 MODELS SHOWING THE HIGH STARTING TO MOVE EAST ON FRIDAY AS A
TROUGH EJECTS EASTWARD OUT OF THE CENTRAL ROCKIES. THE TROUGH IS
EXPECTED TO PUSH THROUGH THE DAKOTAS FRIDAY NIGHT AND INTO WESTERN
MINNESOTA BY SATURDAY MORNING. FORECAST MODEL ARE SHOWING SOME
DIFFERENCES BRINGING THE TROUGH ACROSS THE REGION ON SATURDAY. THERE
APPEARS TO BE TWO PIECES OF ENERGY ASSOCIATED WITH THIS FEATURE. THE
BULK OF THE PRECIPITATION SHOULD OCCUR ACROSS NORTHERN
MINNESOTA...WHERE THE MAIN UPPER LEVEL WAVE IS EXPECTED TO TRACK.
THE GFS SHOWS A SECONDARY SHORTWAVE MOVING THROUGH LATE SATURDAY
AFTERNOON INTO SUNDAY. THE ECMWF DOESNT INDICATE THIS SECONDARY
WAVE...KEEPING THE FORECAST AREA MAINLY DRY ON SATURDAY. HAVE LEANED
TOWARD A MODEL CONSENSUS BLEND MAINTAINING A CHANCE OF SHOWERS AND
ISOLATED THUNDERSTORMS THROUGH THE DAY ON SATURDAY. PLAN ON HIGH
TEMPERATURES IN THE UPPER 50S TO LOWER 60S ON SATURDAY. RAIN CHANCES
WILL SHIFT EAST OF THE AREA SATURDAY NIGHT WITH BREEZY WESTERLY
WINDS SETTING UP ACROSS THE REGION ON SUNDAY. SLIGHTLY COOLER
TEMPERATURES CAN BE EXPECTED ACROSS THE AREA WITH HIGHS IN THE 50S.
ANOTHER TROUGH WILL DROP INTO THE UPPER MISSISSIPPI RIVER VALLEY ON
MONDAY FROM SOUTHERN MANITOBA/ONTARIO BRINGING A SLIGHT CHANCE OF
SHOWERS TO THE FORECAST AREA. LOOK FOR HIGHS ON MONDAY TO RANGE FROM
THE UPPER 40S ACROSS NORTH CENTRAL WISCONSIN TO THE MID 50S ACROSS
NORTHEAST IOWA.
&&
.AVIATION...TODAY AND TONIGHT
649 AM CDT TUE APR 3 2012
A COLD FRONT MOVING THROUGH ALOFT HAS HELPED SPARK A FEW SHOWERS
AND STORMS NEAR THE KLSE TAF SITES. ANTICIPATING THESE TO MOVE
SOUTHEAST WITH THE FRONT...SO ONLY AN HOUR OF POTENTIAL SHOWERS
AND THUNDERSTORMS COULD IMPACT THE KLSE TAF SITE. GIVEN THE
ISOLATED NATURE...ONLY PUT VCSH IN THE TAF. LIGHTNING IS EVEN MORE
ISOLATED...SO ONLY THE CB IS IN THE TAF. OTHERWISE...MVFR TO VFR
STRATUS HAS FILTERED INTO THE TAF SITES IN THE WAKE OF A SURFACE
COLD FRONT THAT MOVED THROUGH OVERNIGHT. MVFR CEILINGS HAVE BEEN
CONFINED TO KRST AND VFR AT KLSE. ANTICIPATING THIS STRATUS TO
REMAIN IN PLACE THROUGH 20Z...WITH DAYTIME MIXING ALLOWING
CEILINGS TO RISE. BETWEEN 20-22Z...DRIER AIR HELPING TO CLEAR
SKIES IN NORTHWEST MINNESOTA WILL MOVE IN AND CLEAR SKIES AT THE
TAF SITES. VFR CONDITIONS ARE THEN ANTICIPATED TO CONTINUE THROUGH
TONIGHT. SHOULD SEE SOME GUSTY NORTHERLY WINDS TODAY...AHEAD OF
HIGH PRESSURE BUILDING INTO NORTHWEST MINNESOTA. GUSTS OF 15 TO 25
KTS ARE POSSIBLE...HIGHEST AT KRST. LOSS OF HEATING THIS EVENING
WILL ALLOW GUSTS TO DIMINISH.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
349 AM CDT TUE APR 3 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
UPDATE...AJ
SHORT TERM...WETENKAMP
LONG TERM...WETENKAMP
AVIATION...AJ
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
408 AM CDT TUE APR 3 2012
UPDATED TO ADD SHORT TERM..AVIATION AND MARINE.
.SHORT TERM...TODAY AND TONIGHT. FORECAST CONFIDENCE MEDIUM.
ELEVATED THUNDERSTORMS THAT DEVELOPED OVER MSP EARLIER IN REGION OF
STRONG LAYER FRONTOGENETIC FORCING ON NOSE OF S-SW 30-45 KT 850 MB
WINDS IMPINGING ON BAROCLINIC ZONE DRAPED ACROSS NRN/CENTRAL WI.
FORCING WEAKENS AS THESE WINDS WEAKEN AND VEER TO THE WEST WITH THE
BEST CROSS-ISOTHERM FLOW SHIFTING EAST OF STATE BY 12Z. THIS SHIFT
NOTED WITH LATEST DEVELOPMENT TO THE EAST OVER LAKE MICHIGAN...IN
LINE WITH RUC AND OTHER SHORT TERM MODEL GUIDANCE.
HAVE BACKED OFF POPS FOR THE ENTIRE CWA THIS MORNING...BUT COULD NOT
DROP COMPLETELY THIS AFTERNOON AS COULD SEE A FEW LIGHT RAIN SHOWERS
WITH CONVERGENCE ALONG BAROCLINIC ZONE AS IT MOVES SOUTH THROUGH
CWA THIS AFTERNOON. SOME ELEVATED CAPE WITH BOUNDARY...BUT FORECAST
SOUNDINGS SHOW A CAP BETWEEN 800 MB AND 700 MB SO WILL ONLY MENTION
ISOLATED THUNDER.
HIGHS TO BE REACHED LATE MORNING/EARLY AFTERNOON THEN DROP WITH COLD
AIR ADVECTION WITH DEVELOPING NORTH TO NORTHEAST WINDS. 925MB TEMPS
SUPPORT HIGHS IN THE MID TO UPPER 60S SOUTH AND SOUTHWEST...WITH MID
UPPER 50S NORTHEAST.
CLEARING FROM NORTH TO SOUTH OVERNIGHT...THOUGH A FEW CLOUDS MAY
LINGER IN THE FAR SOUTH. COLD ADVECTION CONTINUES WITH LOWS DIPPING
INTO THE MID 30S NORTH...AND UPPER 30S TO AROUND 40 IN THE SOUTH BY
MORNING. COULD SEE SOME PATCHY FROST IN THE NORTH...BUT NOT
EXPECTING ENOUGH TO MENTION FOR NOW.
WEDNESDAY THROUGH FRIDAY...FORECAST CONFIDENCE...MEDIUM TO HIGH
SFC HIGH PRESSURE CENTERED JUST TO THE NORTH OF MINNESOTA WEDNESDAY
MORNING WILL MEANDER SOUTHEAST TO MICHIGAN BY FRIDAY.
MEANWHILE...UPPER RIDGING WILL BUILD BACK INTO THE AREA BEHIND
EXITING UPPER LOW TO THE SOUTH. OVERALL...LOOKS LIKE A VERY DRY
AIRMASS ACROSS SOUTHERN WISCONSIN FOR THE SECOND HALF OF THE WORK
WEEK. NO PRECIP CURRENTLY EXPECTED...WITH ONLY PASSING HIGH CLOUDS
AT TIMES.
THOUGH SKIES WILL BE MOSTLY SUNNY...MODELS ARE INDICATING A PUSH OF
COLDER AIR INTO THE STATE FROM THE NORTHEAST WEDNESDAY NIGHT INTO
THURSDAY. IN ADDITION...PERSISTENT EASTERLY WINDS WILL KEEP CHILLY
AIR COMING IN OFF THE LAKE. EVEN SO...HIGH TEMPERATURES WILL
STILL BE NEAR NORMAL FOR EARLY APRIL...EVEN A BIT ABOVE NORMAL
WEDNESDAY AND FRIDAY AWAY FROM THE LAKE. MAY SEE SOME FROST WITH
LOWS TEMPS MORE TOWARD NORMAL...PARTICULARLY THU NIGHT WHEN THE
WINDS WILL BE FAIRLY LIGHT.
SATURDAY THROUGH MONDAY...FORECAST CONFIDENCE...MEDIUM
MODELS SHOWING A PAIR OF WAVES TO SLIDE THROUGH SAT/SAT NIGHT AND
SUN NIGHT/MONDAY. ENOUGH CONFIDENCE TO KEEP SOME POPS GOING. LOOKS
LIKE HIGH TEMPS WILL BE 5 TO 10 DEGREES ABOVE NORMAL THROUGH THE
WEEKEND AND POSSIBLY INTO EARLY NEXT WEEK. WESTERLY LOW LEVEL FLOW
MAY EVEN PUSH THE MILDER TEMPS TO THE LAKE...ESPECIALLY IF STRONG
ENOUGH TO OVERCOME THE LAKE BREEZE POTENTIAL THROUGH THE DAY.
.AVIATION/12Z TAFS...
CONVECTION HAS DEVELOPED WELL TO THE NORTH AND EAST OF TAF SITES
EARLY THIS MORNING...REDUCING PROSPECTS OF SEEING ANY CONVECTION
TODAY. WILL MONITOR TRENDS OVER THE NEXT FEW HOURS...BUT PLAN IS TO
LEAVE ANY PRECIPITATION OUT OF 12Z TAFS. VFR CONDITIONS EXPECTED
THROUGH THE PERIOD....WITH COLD ADVECTION STRATUS TO REMAIN IN THE
3500-4000 FT RANGE. EASTERLY WINDS WILL SHIFT TO THE NORTH-NORTHEAST
LATE THIS MORNING AND INCREASE TO 10 TO 15 KNOTS WITH GUSTS TO 20 TO
25 KNOTS THIS AFTERNOON AS SURFACE LOW PASSES TO THE SOUTH.
.MARINE...
HELD OFF ON A SMALL CRAFT ADVISORY FOR TONIGHT AS WINDS AND WAVES
REMAIN JUST BELOW CRITERIA WITH WINDS EASING A BIT TONIGHT. GRADIENT
TIGHTENS ON WEDNESDAY WITH WAVES BUILDING TO SMALL CRAFT CRITERIA BY
WEDNESDAY NIGHT IN PERSISTENT NORTH-NORTHEAST FLOW. WAVES WILL
REMAIN HIGH INTO THURSDAY...THEN LOWER WITH SHORTER FETCH AS WINDS
VEER TO THE EAST AND EASE.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...NONE.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...REM
WEDNESDAY THROUGH MONDAY...DDV
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1130 PM CDT MON APR 2 2012
.SHORT TERM...OVERNIGHT
1130 PM CDT MON APR 2 2012
THE 03.00Z GFS CONTINUES TO OVERDUE THE PRECIPITATION ACROSS THE
AREA. AS A RESULT...IGNORED IT WITH THIS UPDATE AND INSTEAD LEANED
MORE TOWARD THE NAM/WRF...RUC...AND HRRR SOLUTIONS WHICH SHOW THAT
THE BEST MOISTURE TRANSPORT WILL BE FOUND ALONG AND NORTH OF THE
INTERSTATE 94 CORRIDOR. AS A RESULT...RAISED THE PRECIPITATION
CHANCES IN CLARK AND TAYLOR COUNTY TO CATEGORICAL FOR OVERNIGHT.
WHILE THE 0-6 KM SHEAR IS GREATER THAN 40 KNOTS...MUCH OF THIS IS
BEING AIDED BY THE WINDS IN THE LOWEST 1 KM. WHEN THIS ACCOUNTED
FOR...THESE VALUES ARE LESS THAN 20 KNOTS. WE HAVE HAD A FEW HAIL
REPORTS NEAR THE CITIES...BUT THIS IS MAINLY A RESULT OF THE
ELEVATED CAPE UP 1500 J/KG. THIS IS JUST ENOUGH TO PRODUCE SOME
HAIL UP TO ONE INCH...BUT THE THREAT WOULD BE VERY ISOLATED AND
SHORT LIVED.
.LONG TERM...THURSDAY THROUGH MONDAY
249 PM CDT MON APR 2 2012
THE HIGH WILL REMAIN OVER THE REGION THROUGH FRIDAY MAINTAINING THE
POSSIBILITY OF SOME FROST AND FREEZING TEMPERATURES AT NIGHT FOR
THE END OF THE WEEK. THE HIGH WILL THEN MOVE OFF FOR THE WEEKEND
AS THE NEXT SYSTEM COMES INTO THE AREA. SOME TIMING DIFFERENCES
BETWEEN THE 02.12Z GFS...ECMWF AND GEM WITH THE COLD FRONT COMING
ACROSS. THE ECMWF AND GEM ARE A LITTLE FASTER BUT ALL SHOW AT
LEAST A CHANCE FOR SOME RAIN SATURDAY INTO SATURDAY NIGHT BEFORE
IT MOVES OFF TO THE EAST FOR SUNDAY. SOME DIFFERENCES FOR NEXT
MONDAY WITH THE ECMWF DROPPING ANOTHER SHORT WAVE TROUGH OVER THE
AREA FOR THE POSSIBILITY OF SOME SHOWERS WHILE THE GFS IS DRY WITH
HIGH PRESSURE BUILDING IN. WILL HONOR THE ECMWF WITH A SMALL RAIN
CHANCE FOR MONDAY.
&&
.AVIATION...THROUGH 06Z WEDNESDAY
1130 PM CDT MON APR 2 2012
AN AREA OF SHOWERS AND THUNDERSTORMS HAVE DEVELOPED BETWEEN THE
TWIN CITIES AND EAU CLAIRE. A FEW OF THESE THUNDERSTORMS HAVE
PRODUCED UP TO DIME SIZE HAIL IN THE CITIES. THESE THUNDERSTORMS
WILL STAY NORTH OF BOTH THE TAF SITES...SO NO PLANS TO INCLUDE
THEM IN THE TAFS. HWOEVER THERE MAY BE SOME SCATTERED SHOWERS IN
THE WAKE OF THE COLD FRONT. THIS FRONT WILL MOVE THROUGH KRST
AROUND 03.08Z AND KLSE AROUND 03.10Z. IN ADDITION...THE WINDS
WILL SHIFT FROM EAST TO NORTH AND CIELINGS WILL BECOME MVFR. THESE
CEILINGS WILL THEN GRADUALLY RISE AND BECOME VFR DURING THE MID TO
LATE AFTERNOON...AND THEN MOVE OUT OF THE AREA DURING THE EARLY
EVENING.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
1130 PM CDT MON APR 2 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...04
AVIATION...BOYNE
AREA FORECAST DISCUSSION
NWS DULUTH MN
317 AM CDT THU APR 5 2012
.SHORT TERM...TODAY THROUGH FRIDAY.
AN UPPER LEVEL RIDGE AND SURFACE HIGH TO THE EAST/NORTHEAST WILL
PROVIDE PLENTY OF SUNSHINE AND DRY WEATHER THROUGH THE PERIOD.
IT WILL BE A BIT COOLER TODAY WITH ONSHORE WINDS CONTINUING AROUND
LAKE SUPERIOR. HIGHS WILL RANGE FROM 55 TO 60 WELL IN OUR
WESTERN/SOUTHERN ZONES...TO 45 TO 50 CLOSER TO LAKE SUPERIOR.
CLEAR SKIES TONIGHT AND LIGHT WINDS OVER CENTRAL AND EASTERN ZONES
WILL ALLOW TEMPERATURES TO DROP INTO THE TWENTIES FOR MOST AREAS.
MOSTLY SUNNY SKIES ON FRIDAY AND INCREASING SOUTHEASTERLY WINDS
WILL ALLOW TEMPS TO WARM INTO THE UPPER FIFTIES TO LOWER SIXTIES
WELL INLAND FROM LAKE SUPERIOR...WITH AREAS CLOSER TO LAKE
SUPERIOR COOLER DUE TO CONTINUED ONSHORE WINDS. THE SOUTH SHORE
WILL REACH THE MID FIFTIES TO AROUND SIXTY AS WINDS TURN MORE OUT
OF THE SOUTHEAST THROUGH THE DAY.
.LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY.
A RIDGE OF HIGH PRESSURE OVER THE GREAT LAKES WILL MOVE OFF TO THE
EAST AND GIVE WAY TO A LOW PRESSURE SYSTEM OVER THE PLAINS WHICH IS
PROGGED TO LIFT NEWD OVER NWRN ONTARIO BY SATURDAY NIGHT. A TRAILING
COLD FRONT WILL SWEEP EWD ACROSS THE UPPER MIDWEST SATURDAY INTO
SATURDAY NIGHT...BRINGING A CHANCE OF SHOWERS AND POSSIBLY SOME
THUNDERSTORMS TO THE NORTHLAND. COOL AND BLUSTERY WEATHER WITH A
CHANCE OF RAIN/SNOW SHOWERS IS THEN EXPECTED FOR SUNDAY INTO MONDAY
AS THE PARENT UPPER LEVEL TROUGH MOVES ACROSS THE REGION. ANOTHER
RIDGE OF HIGH PRESSURE FROM CANADA WILL BUILD BACK OVER THE UPPER
MIDWEST...RESULTING IN DRIER CONDITIONS AND SEASONAL TEMPS.
&&
.AVIATION.../06Z TAF ISSUANCE/
THE RUC13 925MB WINDS AND NAM12 1000MB-950MB WINDS INDICATE SOUTHEAST
WINDS OF UP TO 30 KNOTS OVERNIGHT SO INCLUDED WIND SHEAR AT 1K AGL
THROUGH 12Z. VAD WIND PROFILES FROM DLH HAVE BEEN CONSISTENT THE
PAST TWO HOURS WITH 30 KNOT WINDS FROM THE SOUTHEAST ABOVE THE SURFACE.
OTHERWISE...VFR CONDITIONS WILL CONTINUE THROUGH THE TAF PERIOD.
&&
.POINT TEMPS/POPS...
DLH 50 28 56 34 / 0 0 0 10
INL 56 24 60 36 / 0 0 0 10
BRD 59 31 62 40 / 0 0 0 20
HYR 58 22 62 33 / 0 0 0 10
ASX 48 25 58 34 / 0 0 0 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...SMALL CRAFT ADVISORY UNTIL 10 PM CDT THIS EVENING FOR LSZ144-145.
&&
$$
SHORT TERM...MELDE
LONG TERM....BERDES
AVIATION...KK
AREA FORECAST DISCUSSION
NWS DULUTH MN
1226 AM CDT THU APR 5 2012
.AVIATION.../06Z TAF ISSUANCE/
THE RUC13 925MB WINDS AND NAM12 1000MB-950MB WINDS INDICATE SOUTHEAST
WINDS OF UP TO 30 KNOTS OVERNIGHT SO INCLUDED WIND SHEAR AT 1K AGL
THROUGH 12Z. VAD WIND PROFILES FROM DLH HAVE BEEN CONSISTENT THE
PAST TWO HOURS WITH 30 KNOT WINDS FROM THE SOUTHEAST ABOVE THE SURFACE.
OTHERWISE...VFR CONDITIONS WILL CONTINUE THROUGH THE TAF PERIOD.
&&
.PREV DISCUSSION... /ISSUED 856 PM CDT WED APR 4 2012/
UPDATE...
INCREASED WINDS OVER AND ADJACENT TO LAKE SUPERIOR TONIGHT. KDYT
IS REPORTING A NE WIND SUSTAINED AT 16 KT. THE 18Z NAM/DLHWRF BOTH
HAVE PICKED UP ON THE INCREASED NE FLOW OVER LK SUP TONIGHT AND
SUGGEST IT PERSISTS OVERNIGHT AND THROUGH THE DAY THURSDAY. IN
RESPONSES TO THE ELEVATED ONSHORE FLOW OVERNIGHT...HAVE INCREASED
TEMPERATURES FOR LOCATIONS ALONG THE LAKESHORE.
PREV DISCUSSION... /ISSUED 632 PM CDT WED APR 4 2012/
AVIATION.../0Z TAF ISSUANCE/
VFR CONDITIONS WILL PREVAIL THROUGH THE TAF PERIOD. WINDS WILL BE
LIGHT TONIGHT AND BECOME SOUTHEASTERLY BY 15Z OVER THE WESTERN
AERODROMES. THE TERMINALS AT DLH AND HYR WILL HAVE EASTERLY WINDS
BY LATE THURSDAY MORNING.
PREV DISCUSSION... /ISSUED 314 PM CDT WED APR 4 2012/
SHORT TERM...THIS EVENING THROUGH THURSDAY NIGHT...
SHARP RIDGING ALOFT WILL CONTINUE AS STRONG SURFACE HIGH PRESSURE
BUILDS DOWN FROM HUDSON BAY INTO THE LAKE SUPERIOR BASIN. SO FAR
THE GRADIENT AND ONSHORE WINDS ARE WEAK SINCE THE HIGH HAS NOT HAD
A CHANCE TO BUILD UP STRONGLY OVER LAKE SUPERIOR. AIR ASSOCIATED
WITH THE HUDSON BAY IS ARCTIC...TEMPERATURES HAVE BEEN MODIFIED
BUT MOISTURE HAS NOT BEEN ADDED. SO...THE PERIOD WILL HAVE CLEAR
SKIES AND LARGE DAY TO NIGHT TEMPERATURE DIFFERENCES...ESPECIALLY
INLAND. DURING THURSDAY AFTERNOON AND EVENING...HIGH PRESSURE WILL
BECOME MORE ESTABLISHED AND DEEPER...AS SURFACE PRESSURES BEGIN TO
FALL TO OUR WEST. THIS WILL ACCELERATE ONSHORE WINDS BEGINNING
THURSDAY AFTERNOON AND CHILL AREAS NEAR LAKE SUPERIOR. EVEN DRIER
AIR WILL RESULT IN COLDER TEMPERATURES THURSDAY NIGHT AS COMPARED
TO TONIGHT.
LONG TERM...FRIDAY THROUGH NEXT THURSDAY...
THE NORTHLAND SHOULD END THE WORK WEEK WITH A RELATIVELY WARM AND
SUNNY DAY AS HIGH PRESSURE DOMINATES THE GREAT LAKES REGION. A
COLD FRONT IS PROJECTED TO MOVE THROUGH THE REGION EARLY THIS
WEEKEND...AND IT COULD BRING SHOWERS TO THE NORTHLAND LATE FRIDAY
NIGHT AND INTO SATURDAY NIGHT. THERE COULD BE ISOLATED THUNDER ON
SATURDAY. SHOWERS COULD LINGER SUNDAY INTO MONDAY AS THE UPPER
LEVEL LOW MOVES THROUGH THE REGION. THERE COULD BE PERIODS OF A
MIX OF RAIN AND SNOW AS THE COLDER AIR WRAPS IN BEHIND THE SYSTEM.
&&
.POINT TEMPS/POPS...
DLH 28 54 34 54 / 0 0 10 50
INL 24 60 36 53 / 0 0 10 50
BRD 30 60 40 57 / 0 0 20 50
HYR 22 59 32 60 / 0 0 10 50
ASX 26 56 34 59 / 0 0 10 40
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...SMALL CRAFT ADVISORY UNTIL 10 PM CDT THIS EVENING FOR LSZ144-145.
&&
$$
AVIATION...KK
AREA FORECAST DISCUSSION
NWS RALEIGH NC
310 AM EDT THU APR 5 2012
.SYNOPSIS...
A COLD FRONT WILL PUSH SOUTH ACROSS THE AREA THIS MORNING...THEN
STALL OVER SC THIS AFTERNOON. LOW PRESSURE DEVELOPING ALONG THE
FRONT TONIGHT WILL MOVE OFFSHORE ON FRIDAY...WITH HIGH PRESSURE
BUILDING IN FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 AM THURSDAY...
WHILE THE MOST RECENT BATCH OF SHOWERS AND STORMS OVER THE EASTERN
CWA HAS MOVED TO THE COASTAL PLAIN...THE PRESENCE OF DISTURBED
NORTHWESTERLY FLOW ALOFT AND SCATTERED RADAR ECHOES FROM NC TO KY
WARRANTS KEEPING CHANCE POPS IN THROUGH MUCH OF THE MORNING. THE
SURFACE COLD FRONT IS CURRENTLY APPROACHING THE NC/VA BORDER FROM
THE NORTH...AND WE HAVE FOLLOWED THE HRRR WITH RESPECT TO TIMING OF
THE FROPA...WITH THE FRONT PUSHING TO NEAR THE NC/SC BORDER BY
AROUND 12Z. MODELS SHOW SHOWERS BECOMING INCREASINGLY FOCUSED
NEAR THE WEAK 850MB FRONT THAT WILL HOLD BACK OVER VA THIS
MORNING...SO AFTER 12Z WE WILL HAVE A RELATIVE MINIMUM OF SLIGHT
CHANCE POPS BETWEEN THE 850MB FRONT TO THE NORTH AND SURFACE COLD
FRONT TO THE SOUTH. WITH THE COLD FRONT SETTLING INTO SC...THE
INSTABILITY GRADIENT SHOULD SET UP JUST SOUTH OF THE NC/SC BORDER.
MOST HI-RES MODELS SUGGEST SCATTERED CONVECTION WILL DEVELOP IN THE
WARM SECTOR...BUT THERE IS VERY GOOD MODEL AGREEMENT THAT AREA NORTH
OF THE BORDER WILL BE MUCH TO STABLE TO SUPPORT THUNDERSTORMS.
LOW LEVEL COLD/DRY ADVECTION WILL STABILIZE THE BOUNDARY LAYER OVER
NC AND HELP LOCK IN STRATUS THIS MORNING..SO WE EXPECT CLOUDY
CONDITIONS ALL DAY WITH A STEADY 12KT NORTHEAST WIND. THUS TEMPS
WILL CONTINUE TO FALL THROUGH THE EARLY MORNING HOURS AND RISE VERY
LITTLE THIS AFTERNOON. MANY LOCATIONS ACROSS THE SOUTH HAVE BEEN
COOLED BY RAIN AND FORECAST TEMPS ARE ALREADY TOO WARM. A 10 TO 15
DEGREE WARM UP DIFFICULT TO ATTAIN TODAY...SO WE WILL NUDGE HIGHS
ACROSS THE SOUTH DOWN THE UPPER 60S.
&&
.SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...
AS OF 300 AM THURSDAY...
THE UPPER LOW CURRENTLY OVER OK WILL PUSH EAST ACROSS THE MID MS
VALLEY REGION TODAY...THEN DIP SOUTHEAST ACROSS AL/GA TONIGHT AS IT
BECOMES ABSORBED INTO THE CYCLONIC UPPER FLOW OVER THE NEW ENGLAND
AND THE MID ATLANTIC STATES. 60-80M HEIGHT FALLS AND INCREASINGLY
DIFFLUENT FLOW ALOFT AHEAD OF THE UPPER LOW WILL LEAD TO
CYCLOGENESIS ALONG THE COLD FRONT NEAR THE SC/GA BORDER LATE THIS
EVENING AND OVERNIGHT. THE GFS IS A NORTHERN OUTLIER WITH ITS
PRESSURE FALLS AND EVENTUALLY TRACK OF THE SURFACE LOW. WE WILL
FAVOR THE ECMWF AND NAM FOR THEIR CONSISTENCY WITH THE TRACK OF THE
LOW. MOST OF THE RAIN WITH THE SYSTEM WILL BE FOCUSED ALONG THE
FRONT AND SURFACE LOW...BUT A SHORTWAVE DROPPING SOUTH OUT OF
EASTERN CANADA INTO THE MID-ATLANTIC STATES SHOULD HELP DRAW
MOISTURE NORTH INTO THE VICINITY OF THE 925-850MB FRONT WHICH IS
FORECAST TO LIE ACROSS THE CAROLINAS OVERNIGHT. THUS WHILE RAIN MAY
INITIALLY BE SLOW TO PROGRESS ACROSS THE SOUTHERN PIEDMONT AFTER
21-00Z THIS EVENING...THE RAIN SHIELD IS EXPECTED TO EXPAND
NORTHWARD ACROSS MOST OF THE CENTRAL NC. A MODEL CONSENSUS OF
QPF...WITH GENERALLY GOOD AGREEMENT AMONG MODELS...GIVES 0.25-0.5"
FOR AREAS SOUTH OF HWY 64. IT IS POSSIBLE THAT AREA NEAR THE VA
BORDER COULD SEE LITTLE TO NO RAIN IF THE SURFACE LOW TRACKS FURTHER
SOUTH WHERE MOST MODELS SHOW IT TRACKING. LOWS WILL FALL INTO THE
UPPER 40S...WITH A CHILLY 10-15KT NORTHEAST WIND ON THE NORTHWESTERN
SIDE OF THE SURFACE LOW.
ONCE THE SURFACE LOW MOVES OFFSHORE FRIDAY MORNING...WINDS WILL
SLOWLY BACK AROUND TO NORTHERLY DURING THE DAY ON FRIDAY...HELPING
TO FILTER DIRER AIR IN FROM THE NORTH. MODELS CONTINUE TO TREND
TOWARD ALL OF THE CWA CLEARING BY FRIDAY EVENING. BECAUSE
CLOUDS...AND PRECIP EARLY...WILL LINGER LONGEST ON THE
SOUTHEAST...TEMPS SHOULD BE FAIRLY UNIFORM ACROSS THE AREA...IF NOT
WARMER ACROSS THE NORTH. WE WILL CONTINUE THE FORECAST OF HIGHS IN
THE LOWER 60S. HIGH PRESSURE WILL BUILD IN FROM THE GREAT LAKES
FRIDAY NIGHT...LEADING TO A MUCH DRIER AIRMASS OVER CENTRAL NC AND
POTENTIAL FOR LOWS TO REACH THE UPPER 30S. A LIGHT WIND SHOULD KEEP
TEMPS FROM REACHING THEIR FULL RADIATIONAL COLLING POTENTIAL...BUT A
LIGHT FROST COULD BE POSSIBLE IN COOLER SHELTERED AREAS.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 300 AM THURSDAY...
THE LONG TERM PERIOD WILL START OFF WITH HIGH PRESSURE BUILDING
SOUTHEASTWARD ACROSS THE CAROLINAS ON SATURDAY IN THE WAKE OF A
SHORT WAVE MOVING OFF THE EAST COAST. WORTH NOTING THE CANADIAN
ORIGIN OF THIS HIGH AND ASSOCIATED COOL AIRMASS FOR THIS TIME OF
THE YEAR...HOWEVER COLDEST AIR WILL SLIDE BY TO OUR EAST AS THE
TROUGH BOTTOMS OUT OVER THE WESTERN ATLANTIC. NONETHELESS...LATEST
GUIDANCE IS IN LINE WITH ONGOING TEMP FORECAST WHICH SUGGESTS LOWS
SATURDAY MORNING IN THE MID 30S...COLDEST NORTH OF HWY 64. CAN`T
RULE OUT THE POSSIBILITY OF SOME FROST AROUND SUNRISE SATURDAY
MORNING IN THE COLDER/SHELTERED SPOTS...BUT GUIDANCE DOES SHOW THE
PRES GRADIENT AND SOME SFC WIND PERSISTING THROUGH SUNRISE...SO THAT
COULD HELP TO PRECLUDE WIDESPREAD COLDER TEMPS AND FROST. THEN THE
REMAINDER OF THE DAY WILL BE SUNNY WITH A DRY AIRMASS IN PLACE AND
HIGHS ABOUT 5 DEGREES BELOW NORMAL.
THE HIGH WILL MOVE SOUTH OF THE CAROLINAS SATURDAY NIGHT AS THE NEXT
SHORT WAVE MOVES FROM THE NORTHERN PLAINS TO THE GREAT LAKES. WITH A
CHILLY AND DRY AIRMASS STILL IN PLACE OVER OUR AREA AND LIGHT TO
CALM WINDS OVERNIGHT...LOWS SUNDAY MORNING WILL BE COLD ONCE AGAIN.
RIGHT NOW GUIDANCE SUGGESTS TEMPS WILL BE SEVERAL DEGREES WARMER
THAN SATURDAY MORNING...BUT ALSO EXPECT LESS WIND SUNDAY MORNING
COMPARED TO SATURDAY...THUS TEMPS MAY BE CLOSE TO VALUES NEEDED FOR
PATCHY FROST. IT WILL DEFINITELY BE WORTH CHECKING BACK FOR UPDATES
WITH LATER FORECASTS.
ON SUNDAY...THE AFOREMENTIONED SHORT WAVE WILL DIVE SE ACROSS
THE GREAT LAKES AND ITS ATTENDANT SFC COLD FRONT WILL MOVE FROM THE
TN VALLEY IN THE MORNING TO OUR WESTERN PIEDMONT BY EVENING. WITH A
DRY AIRMASS IN PLACE AND MODEST MOISTURE TRANSPORT INTO THE FRONTAL
SYSTEM FROM THE SOUTH (THANKS TO HIGH PRESSURE OVER THE DEEP SOUTH
AND WNW MIDLEVEL FLOW GENERALLY EAST OF THE MISSISSIPPI)...I`M A
LITTLE LEARY OF THE PRECIP THAT THE GFS IS GENERATING OVER OUR AREA
LATE SUNDAY AND PREFER THE DRIER ECMWF SOLUTION. FOR NOW WILL KEEP
POPS AOB 10 PERCENT FOR THIS TIME...BUT IF GUIDANCE CONTINUES TO
TREND WETTER...MAY NEED TO INCREASE POPS FOR THIS TIME WITH FUTURE
FORECAST CYCLES.
THEREAFTER...THE PATTERN WILL CONTINUE TO AMPLIFY AND TREND COOLER
OVER THE EASTERN PORTION OF NORTH AMERICA AS A SERIES OF SHORT WAVE
TROUGHS DEEPEN THE LONG WAVE PATTERN ...PARTICULARLY OVER THE
NORTHEAST STATES AND EXTENDING SOUTH ACROSS OUR AREA. WHAT THIS
MEANS FOR US IS A CONTINUATION OF THE COOL TREND FOR THE EARLY TO
MIDDLE PART OF THE WEEK...WITH MORNING FROST/FREEZE POTENTIAL...
PARTICULARLY DURING THE MIDDLE PART OF THE WEEK. THE EXACT TIMING
AND DETAILS WILL BE ASSOCIATED WITH THE TIMING AND STRENGTH OF
INDIVIDUAL SHORT WAVES ROTATING AROUND THE LONG WAVE TROUGH...BUT
RIGHT NOW LOOKS LIKE ONE POTENT SHORT WAVE WILL MOVE ACROSS THE AREA
LATE MONDAY OR EARLY TUESDAY MORNING WITH INCREASED POPS ALONG/AHEAD
OF IT...AND THEN ANOTHER SHORT WAVE PASSAGE ON WEDNESDAY. SURGES OF
COOLER AIR WILL FOLLOW EACH OF THESE WAVES.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
AS OF 125 AM THURSDAY...
MUCH OF THE SHOWER AND THUNDERSTORM ACTIVITY THAT HAS BEEN MOVING
NORTHWEST TO SOUTHEAST ACROSS THE AREA HAS DIMINISHED OR MOVED TO
THE COASTAL PLAIN AS OF 06Z. A COLD FRONT LOCATED OVER CENTRAL VA
WILL PUSH SOUTH THROUGH CENTRAL NC OVERNIGHT...WITH WINDS SHIFTING
TO NORTH-NORTHEASTERLY BEHIND THE FRONT BETWEEN 08Z AND 12Z. DEEP
MOISTURE WILL REMAIN HIGH...AND A SERIES OF WEAK DISTURBANCES ALOFT
DRIFTING FROM KENTUCKY ACROSS NC/VA...ALONG WITH THE COLD
FRONT...MAY CONTINUE TO PROMOTE PERIODS OF SHOWERS OR ISOLATED
THUNDERSTORMS OVERNIGHT. CEILINGS AND VSBYS ARE EXPECTED TO REMAIN
AT VFR LEVELS...WITH CEILINGS SLOWLY FALLING TO AROUND 4-5K FT LATER
THIS MORNING.
BEHIND THE FRONT...NORTHEASTERLY WINDS WILL BE FAIRLY STEADY AROUND
12KT FOR MOST OF THE DAY. SHOWERS...OR POSSIBLY A
THUNDERSTORM...SHOULD BE TOO ISOLATED FOR ANY MENTION IN THE CURRENT
TAF. MODELS ARE CONSISTENT IN SHOWING STRATUS REMAIN ABOVE 3K FT
UNTIL LATER THIS EVENING AS RAIN BEGINS TO SPREAD IN FROM THE
SOUTHWEST AHEAD OF AN UPPER LOW DIVING THROUGH THE SOUTHEAST
STATES. RAIN AND IFR CEILINGS WILL BE MOST PREDOMINATE ACROSS
SOUTHERN NC THURSDAY NIGHT.
AS THE SURFACE LOW THAT IS FORECAST TO DEVELOP ALONG THE SC COAST
MOVES FURTHER OFFSHORE...RAIN WILL COME TO AN END FRIDAY MORNING.
DRIER AIR AD HIGH PRESSURE WILL BUILD FRIDAY AND FRIDAY NIGHT...WITH
VFR CONDITIONS EXPECTED FROM FRIDAY AFTERNOON INTO EARLY NEXT WEEK.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...SMITH
NEAR TERM...SMITH
SHORT TERM...SMITH
LONG TERM...NMP
AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1100 PM CDT WED APR 4 2012
.SHORT TERM...TONIGHT THROUGH SATURDAY
318 PM CDT WED APR 4 2012
MAIN EMPHASIS OF FORECAST WILL BE ON FREEZE CONDITIONS THE NEXT
COUPLE OF NIGHTS ALONG WITH LOW DAYTIME RELATIVE LEVELS THURSDAY
AND FRIDAY.
WATER VAPOR IMAGERY AND RUC 500MB ANALYSIS SHOW A HIGHLY AMPLIFIED
MID-LEVEL RIDGE IN PLACE FROM THE NORTHERN PLAINS INTO MANITOBA AND
HUDSON BAY. MEANWHILE...A CLOSED/CUTOFF LOW WAS SLOWLY MOVING EAST
INTO OKLAHOMA. AT THE SURFACE...HIGH PRESSURE WAS CENTERED OVER
WESTERN ONTARIO. DRY/COOL NORTHEAST FLOW WAS RESULTING ACROSS THE
AREA TODAY UNDER SUNNY SKIES WITH TEMPERATURES IN THE UPPER 50S TO
MIDDLE 60S AND DEWPOINTS WAY DOWN IN THE 20S.
04.12Z NAM/GFS SHOWING GOOD AGREEMENT THROUGH FRIDAY...BUT THEN SOME
DIFFERENCES REGARDING THE STRENGTH OF THE MID-LEVEL TROUGH AND
SURFACE COLD FRONT CROP UP SATURDAY. THE 04.09Z SREF WAS GENERALLY
USED FOR THIS TIME FRAME.
FOR TONIGHT THE MAIN STORY WILL BE CLEAR/DRY CONDITIONS LEADING TO A
RAPID DROP OFF IN TEMPERATURES. WITH THE RIDGE AXIS BUILDING
SOUTHWARD INTO THE REGION...LOOKS LIKE WINDS WILL TAPER OFF TO LESS
THAN 5 MPH MOST PLACES WHICH WILL ALLOW TEMPERATURES TO FALL OFF
INTO THE MIDDLE 20S TO MIDDLE 30S. PLAN ON THE COLDEST AIR TO BE
OVER THE FAVORED COLD SPOTS ALONG/NORTH OF THE I-94 CORRIDOR. AS
SUCH...WILL KEEP FREEZE WARNING HOISTED FOR THIS AREA FROM 2 AM
THROUGH 8 AM THURSDAY.
HIGH PRESSURE WILL CONTINUE TO BE THE DOMINATING WEATHER FEATURE
THROUGH FRIDAY WITH PREVAILING DRY CONDITIONS. CONCERN WILL
AGAIN BE ON THE NEED FOR FREEZE HEADLINES LATE THURSDAY NIGHT INTO
FRIDAY MORNING WITH LOWS DIPPING AGAIN INTO THE MIDDLE 20S AND LOWER
30S ACROSS MUCH OF THE AREA...WITH MID/UPPER 20S MORE PREVALENT EAST
OF THE MISSISSIPPI RIVER. WITH THIS IN MIND...WILL BE EXPANDING THE
FREEZE WATCH TO INCLUDE ALL OF THE AREA. SEE WWA SECTION BELOW AND
LATEST FREEZE WATCH STATEMENT FOR DETAILS.
RIDGE STARTS TO BREAK DOWN/MOVE EAST LATE FRIDAY NIGHT THROUGH
SATURDAY AS A FAIRLY VIGOROUS MID-LEVEL TROUGH PUSHES EAST INTO THE
NORTHERN PLAINS/UPPER MISSISSIPPI RIVER REGION. AS STATED
ABOVE...GFS AND NAM ARE DIFFERING AS TO THE STRENGTH OF THIS WAVE
WITH THE GFS LOOKING A BIT STRONGER. THIS HAS A BEARING ON SURFACE
COLD FRONT STRENGTH AND AMOUNT OF MOISTURE TRANSPORT NORTHWARD INTO
THE AREA FOR THE PRODUCTION OF SHOWERS. WITH THIS IN MIND...WILL
MOVE IN 20-30 PERCENT CHANCE OF SHOWERS TO ABOUT THE MISSISSIPPI
RIVER THROUGH FRIDAY MORNING...INCREASING/EXPANDING TO 40 PERCENT
CHANCE OF SHOWERS/ISOLATED THUNDER SATURDAY AFTERNOON ACROSS THE
ENTIRE AREA.
SHOWERS WILL LINGER INTO SATURDAY EVENING...THEN EXIT WITH THE COLD
FRONTAL PASSAGE AFTER MIDNIGHT.
AS FAR AS DAYTIME HIGH TEMPERATURES THURSDAY THROUGH SATURDAY...PLAN
ON 50S THURSDAY AND FRIDAY...WARMING SOME INTO THE UPPER 50S TO
LOWER 60S ON SATURDAY.
.LONG TERM...SUNDAY THROUGH WEDNESDAY
318 PM CDT WED APR 4 2012
04.12Z GFS AND 04.00Z ECMWF IN OVERALL GOOD AGREEMENT THROUGH THE
LONG TERM PERIOD WITH OVERALL DRY/COOLER CONDITIONS. BOTH MODELS
SHOW THE AREA IN BREEZY DRYING WESTERLY FLOW DURING THE DAY SUNDAY
IN THE WAKE OF THE COLD FRONT AND LOW PASSING THROUGH SOUTHERN
ONTARIO CANADA. BREEZY/COOLER NORTHWEST FLOW INVADES THE AREA MONDAY
THROUGH TUESDAY AS HIGH PRESSURE BUILDS SOUTHWARD INTO THE
PLAINS/UPPER MISSISSIPPI RIVER REGION AND DEEP LOW PRESSURE ANCHORS
OVER QUEBEC. SOME WARMING THEN EXPECTED ON WEDNESDAY AS THE AXIS OF
THE SURFACE RIDGE SHIFTS EAST OF THE REGION AND HEIGHTS BUILD ALOFT.
TEMPERATURE-WISE...LOOK FOR HIGHS IN THE MID-UPPER 50S
SUNDAY...COOLING INTO THE UPPER 40S TO LOWER 50S
MONDAY/TUESDAY...AND THEN BACK INTO THE MID-UPPER 50S WEDNESDAY.
&&
.AVIATION...
1100 PM CDT WED APR 4 2012
VFR CONDITIONS WILL PERSIST INTO FRIDAY AS THE REGION REMAINS UNDER
THE INFLUENCE OF AN AREA OF HIGH PRESSURE. BUFKIT SOUNDINGS AGAIN
SUGGEST DEEP MIXING DURING THE LATE MORNING/AFTERNOON...LIKELY
RESULTING IN SOME GUSTINESS...MAINLY FOR KRST. DECOUPLING BY SUNDOWN
WILL LEAD TO LIGHTER WINDS...LIKELY LIGHT/VRBL AT KLSE. DIRECTIONS
SHOULD STAY EAST/SOUTHEAST THROUGH FRI.
&&
.FIRE WEATHER...THURSDAY THROUGH FRIDAY
318 PM CDT WED APR 4 2012
HUDSON BAY HIGH WILL PUMP A VERY DRY AIRMASS INTO THE REGION
THURSDAY THROUGH FRIDAY. LOOK FOR AFTERNOON MINIMUM RH READINGS IN
THE 20-25 PERCENT RANGE THURSDAY...MODERATING A FEW PERCENTAGE
POINTS INTO THE MID 20S FRIDAY AFTERNOON. WINDS LOOK GENERALLY ON
THE LIGHTER SIDE THURSDAY OUT OF THE EAST SOMEWHERE IN THE 5-12 MPH
RANGE WITH SOME GUSTS AROUND 15 MPH. WINDS ARE THEN EXPECTED TO
INCREASE OUT OF THE SOUTHEAST ON FRIDAY...ESPECIALLY WEST OF THE
MISSISSIPPI RIVER FRIDAY AS THE HIGH BEGINS TO PUSH EAST INTO THE
GREAT LAKES REGION.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
318 PM CDT WED APR 4 2012
WI...FREEZE WATCH FROM LATE THURSDAY NIGHT THROUGH FRIDAY MORNING
FOR WIZ017-029-032>034-041>044-053>055-061.
FREEZE WARNING FROM 2 AM TO 8 AM CDT THURSDAY FOR
WIZ017-029-034- 042>044.
MN...FREEZE WATCH FROM LATE THURSDAY NIGHT THROUGH FRIDAY MORNING
FOR MNZ079-086>088-094>096.
IA...FREEZE WATCH FROM LATE THURSDAY NIGHT THROUGH FRIDAY MORNING
FOR IAZ008>011-018-019-029-030.
&&
$$
SHORT TERM.....DAS
LONG TERM......DAS
AVIATION.......RIECK
FIRE WEATHER...DAS
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1146 AM EDT THU APR 5 2012
.SYNOPSIS...
A LARGE AREA OF HIGH PRESSURE WILL BUILD SOUTHWARD FROM CANADA
TODAY THROUGH THE WEEKEND. A SERIES OF FRONTAL BOUNDARIES ARE
EXPECTED TO AFFECT THE AREA LATE IN THE WEEKEND INTO THE MIDDLE OF
NEXT WEEK AS LOW PRESSURE MOVING THROUGH THE GREAT LAKES MERGES
WITH AN AREA OF LOW PRESSURE IN THE CANADIAN MARITIMES AND CARVES
OUT A TROUGH OVER THE EASTERN HALF OF THE NATION. SOME UNSETTLED
WEATHER IS POSSIBLE DURING THIS TIME.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CURRENT FORECAST PRETTY MUCH STAYING ON COURSE. WE DID NUDGE MAX
TEMPS UP SLIGHTLY AS THE TREND HAS HELD THROUGH THE MORNING. IT
LOOKS LIKE THE CAA STRATOCU CLOUDS UP NORTH ARE RUNNING OUT OF
AVAILABLE MOISTURE. PLUS THERE IS ANOTHER LULL IN THE PRESSURE
PATTERN FORMING OVER OUR CWA. THE ENTRANCE REGION OF THE 250MB JET
IS OVER OUR CWA, SO SOME OF THE MID AND HIGH LEVEL CLOUDS SOUTH
WILL MAKE SOME MOVEMENT INTO OUR CWA THIS AFTERNOON. WE DID UP THE
SKY COVER SOUTH.
TODAY GENERALLY SHOULD BE A BENIGN WEATHER DAY WITH TEMPERATURES
A BIT MORE THAN 10 TO 15 DEGREES COOLER THAN WEDNESDAY THANKS TO
THE COLD FRONT THAT DROPPED THROUGH OUR AREA DURING THE NIGHT.
PERHAPS SOME HIGH CLOUDS WILL BE AROUND (LIKELY MORE SOUTH THAN
NORTH), WINDS STARTED MODERATE FROM THE NORTH, BUT AS A RATHER
WEAK AND DRY TROUGH APPROACHES THE AREA THIS AFTERNOON THEY ARE
EXPECTED TO DIMINISH A BIT. THE H925 FLOW IS IN OPPOSITION TO A
SEA BREEZE LATER TODAY, BUT IT IS ON THE LIGHT SIDE. WE HAVE A SEA
BREEZE DEVELOPING, BUT WE AREN`T CARRYING IT VERY FAR INLAND.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/...
WE ISSUED A FREEZE WARNING FOR THE COUNTIES WE ARE MOST CONFIDENT
WILL REACH FREEZING TEMPERATURES. THERE MAY BE AN EXPANSION LATER
TODAY IN PARTS OF DELMARVA AND THE LOCAL PHL METRO AREA.
SKIES ARE EXPECTED TO BE MAINLY CLEAR TONIGHT. AGAIN, HIGH CLOUDS
WILL BE MORE APPARENT NORTH THAN SOUTH. WINDS ARE EXPECTED TO
LIGHTEN IN A CLIMATOLOGICALLY NORMAL WAY AT FIRST, BUT THE PASSAGE
OF THE TROUGH TONIGHT MAY CAUSE THEM TO PICK UP A LITTLE OVERNIGHT
DESPITE SOME PARTIAL DECOUPLING. WE THEREFORE HAVE BEEN CAREFUL
ABOUT DROPPING THE BOTTOM OUT FROM TEMPERATURES. WE WILL MAINTAIN
THE POSSIBILITY OF FROST OR FREEZING TEMPERATURES OVER MANY
LOCATIONS IN THE HWO. OUR FORECAST MINS ARE A BLEND OF CONTINUITY
AND STAT GUIDANCE.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
A LARGE AREA OF HIGH PRESSURE BUILDING DOWN FROM CANADA WILL BE
THE DOMINANT WX FEATURE FOR THE START OF THE EXTENDD PD. HOWEVER,
IT WILL BE REPLACED BY LOW PRESSURE AND AN H5 TROF FOR THE LATER
PORTION OF THE PD. ON FRIDAY, THE HIGH WILL BEGIN BUILDING IN AS
LOW PRESSURE MOVES OFF THE SERN CONUS COAST. THIS LOW WILL MOVE
WELL OFF THE ATLC COAST BEFORE RETROGRADING WWD TWD THE CANADIAN
MARITIMES EARLY NEXT WEEK. IT SHOULD BE NOTED THAT THE LATEST MDL
RUNS ARE NOW MUCH WEAKER AND FURTHER OFF THE COAST WITH THIS SYS
THAN PREV RUNS, ESPECIALLY THE GFS, AS IT MOVES NWD THEN NWWD.
WITH THE HIGH CONTROLLING THE WX THRU SUNDAY, EXPECT DRY CONDS
WITH SEASONAL TO SLIGHTLY ABV NRML TEMPS. THERE IS VERY HIGH
CONFIDENCE IN THIS PORTION OF THE FCST.
THEN THE MDLS BEGIN TO DIVERGE AND CONFIDENCE DROPS EARLY NEXT
WEEK. THE AFOREMENTIONED LOW PRESSURE SYSTEM MOVES TWD THE
CANADIAN MARITIMES AND THIS FEATURE COUPLED WITH ANOTHER LOW
DROPPING SEWD ACRS THE PLAINS WILL HELP CARVE OUT A LARGE TROF
OVER THE ERN CONUS. SEVERAL WAVES AND WEAK FRONTS WILL ROTATE THRU
THIS TROF THRU MIDWEEK AND BRING SHOTS OF PRECIP TO THE REGION.
HOWEVER, THE GFS,AS USUAL,IS WETTER THAN THE REST OF THE MDL
GUIDANCE, AND AT THIS MDL DISTANCE IT IS DIFFICULT TO PINPOINT
EXACTLY WHEN THE WETTEST PD WILL BE, BUT RIGHT NOW IT LOOKS TO BE
AT SOME POINT TUESDAY OR WEDNESDAY. ALSO, WHILE THE MDLS SEEM TO
HAVE SOME DECENT AGREEMENT ON THE GENERAL FEATURES, THEY DISAGREE
ON JUST HOW THEY INTERACT. SO, FOR NOW, WILL JUST KEEP SCHC AND
LOW CHC POPS.
&&
.AVIATION /16Z THURSDAY THROUGH MONDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
NO CEILINGS OR VISIBILITY LIMITATIONS ARE FORECAST THROUGH
TONIGHT. A MODERATE NORTH WIND IS EXPECTED TO DIMINISH LATER THIS
AFTERNOON BUT THEN PICK UP TOWARD THE END OF THE PERIOD.
LATEST HRRR AND HI RES NMMB SUPPORT THOUGHTS ABOUT A SEA BREEZE
STRUGGLING TO GET MUCH INLAND AND WE MAINTAINED IT TO THE EAST OF
KACY IN 12Z TAFS.
OUTLOOK...
VFR CONDITIONS ARE THRU THE WEEKEND WITH A LARGE AREA OF HIGH
PRESSURE BUILDING DOWN FROM CANADA. WINDS COULD BECOME GUSTY EACH
AFTERNOON THROUGH THE WEEKEND, WITH GUSTS GENERALLY AROUND 15-20
KNOTS.
&&
.MARINE...
WINDS AND SEAS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA
THIS AFTERNOON. WINDS AND SEAS WILL PICK UP SOME TONIGHT WITH THE
PASSAGE OF A WEAK TROUGH, BUT THE PUSH BEHIND THE TROUGH DOESN`T
LOOK AS SUBSTANTIAL AS THE ONE THAT WAS BEHIND THE FRONT THAT CAME
THROUGH DURING THE NIGHT.
OUTLOOK...
HIGH PRESSURE WILL BUILD TO THE WEST OF THE WATERS FRIDAY THROUGH THE
WEEKEND. THE PRESSURE GRADIENT ACROSS THE WATERS SHOULD KEEP A
STEADY NORTH TO NORTHWEST WIND ACROSS THE AREA. IT IS POSSIBLE
THAT WIND GUSTS COULD APPROACH SMALL CRAFT ADVISORY DURING THIS
PERIOD, ESPECIALLY SATURDAY INTO SUNDAY.
&&
.FIRE WEATHER...
WE STILL THINK WINDS WILL FALL SHORT OF THE RED FLAG WARNING
CRITERIA AROUND OUR FORECAST AREA, SO WE WILL ISSUE A SPECIAL
WEATHER STATEMENT TO HIGHLIGHT THE DRY FINE FUELS AND THE LOW
RELATIVE HUMIDITY LEVELS THIS AFTERNOON.
A LOW DEPARTING OFF THE SOUTHEAST COAST MIGHT INCREASE THE GRADIENT
WITH A GREATER CHANCE FOR RED FLAG WARNING CONDITIONS ON FRIDAY AND
ESPECIALLY SATURDAY.
&&
.TIDES/COASTAL FLOODING...
LATE THIS MORNING, DEPARTURES (WERE THEY TO REMAIN CONSTANT)
SUPPORTED THE POSSIBILITY OF JUST REACHING MINOR TIDAL FLOODING
ALONG THE SOUTH COAST AND LOWER DELAWARE BAY. THE OFS, HOWEVER,
SUGGEST THOSE DEPARTURES WOULD DIMINISH AS THE NORTH FLOW
DIMINISHES, AND SO WE THINK IT IS LIKELY THAT WE WILL AVOID ANY
FLOODING THIS EVENING. WE WILL MAINTAIN A MENTION IN THE HWO IN
THE INTEREST OF CAUTION.
AFTER THAT, THE COMBINATION OF THE APPROACHING SPRING TIDES WITH THE
FULL MOON AND THE EKMAN SPIRAL EFFECT FROM THE LIKELY AND
PREDOMINATELY NORTHERLY WINDS NEAR THE COAST MAY CAUSE MINOR TIDAL
FLOODING WITH THE EVENING AND OVERNIGHT HIGH TIDE CYCLES FROM FRIDAY
EVENING INTO THE WEEKEND. BY SATURDAY, WE WILL ONLY NEED DEPARTURES
OF ABOUT HALF A FOOT ABOVE NORMAL TO REACH THE CRITERIA. IN UPPER
DELAWARE BAY, THE TIDAL DELAWARE RIVER AND CHESAPEAKE BAY, THE
NORTHERLY FLOW COUPLED WITH NORMAL OR BELOW NORMAL FRESHWATER RUNOFF
SHOULD MITIGATE ANY TIDAL RELATED PROBLEMS.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...FREEZE WARNING FROM 3 AM TO 8 AM EDT FRIDAY FOR PAZ060>062.
NJ...FREEZE WARNING FROM 3 AM TO 8 AM EDT FRIDAY FOR NJZ007>010-
020>022-027.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...NIERENBERG
NEAR TERM...DELISI/GIGI
SHORT TERM...DELISI/GIGI
LONG TERM...NIERENBERG
AVIATION...DELISI/NIERENBERG
MARINE...DELISI/GIGI/NIERENBERG
FIRE WEATHER...DELISI
TIDES/COASTAL FLOODING...DELISI
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1121 AM EDT THU APR 5 2012
.SYNOPSIS...
A LARGE AREA OF HIGH PRESSURE WILL BUILD SOUTHWARD FROM CANADA
TODAY THROUGH THE WEEKEND. A SERIES OF FRONTAL BOUNDARIES ARE
EXPECTED TO AFFECT THE AREA LATE IN THE WEEKEND INTO THE MIDDLE OF
NEXT WEEK AS LOW PRESSURE MOVING THROUGH THE GREAT LAKES MERGES
WITH AN AREA OF LOW PRESSURE IN THE CANADIAN MARITIMES AND CARVES
OUT A TROUGH OVER THE EASTERN HALF OF THE NATION. SOME UNSETTLED
WEATHER IS POSSIBLE DURING THIS TIME.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NO BIG CHANGES MADE WITH THIS UPDATE. FORECAST ON TRACK. MORNING
12Z SOUNDINGS SUGGEST WE MAY BE A DEGREE OR TWO TOO LOW ON MAX
TEMPS. WE WILL SEE HOW THEY RESPOND THE REST OF MORNING AND MAKE
ANY NEEDED ADJUSTMENTS BY THE NEXT UPDATE. LATEST HRRR AND HI RES
NMMB SUPPORT THOUGHTS ABOUT A SEA BREEZE STRUGGLING TO GET MUCH
INLAND.
TODAY GENERALLY SHOULD BE A BENIGN WEATHER DAY WITH TEMPERATURES
A BIT MORE THAN 10 TO 15 DEGREES COOLER THAN WEDNESDAY THANKS TO
THE COLD FRONT THAT DROPPED THROUGH OUR AREA DURING THE NIGHT.
PERHAPS SOME HIGH CLOUDS WILL BE AROUND (LIKELY MORE SOUTH THAN
NORTH), BUT WE ARE CARRYING A SUNNY FORECAST. WINDS WILL START AS
MODERATE FROM THE NORTH, BUT AS A RATHER WEAK AND DRY TROUGH
APPROACHES THE AREA THIS AFTERNOON THEY ARE EXPECTED TO DIMINISH A
BIT. THE H925 FLOW IS IN OPPOSITION TO A SEA BREEZE LATER TODAY,
BUT IT IS ON THE LIGHT SIDE. WE HAVE A SEA BREEZE DEVELOPING, BUT
WE AREN`T CARRYING IT VERY FAR INLAND.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/...
WE ISSUED A FREEZE WARNING FOR THE COUNTIES WE ARE MOST CONFIDENT
WILL REACH FREEZING TEMPERATURES. THERE MAY BE AN EXPANSION LATER
TODAY IN PARTS OF DELMARVA AND THE LOCAL PHL METRO AREA.
SKIES ARE EXPECTED TO BE MAINLY CLEAR TONIGHT. AGAIN, HIGH CLOUDS
WILL BE MORE APPARENT NORTH THAN SOUTH. WINDS ARE EXPECTED TO
LIGHTEN IN A CLIMATOLOGICALLY NORMAL WAY AT FIRST, BUT THE PASSAGE
OF THE TROUGH TONIGHT MAY CAUSE THEM TO PICK UP A LITTLE OVERNIGHT
DESPITE SOME PARTIAL DECOUPLING. WE THEREFORE HAVE BEEN CAREFUL
ABOUT DROPPING THE BOTTOM OUT FROM TEMPERATURES. WE WILL MAINTAIN
THE POSSIBILITY OF FROST OR FREEZING TEMPERATURES OVER MANY
LOCATIONS IN THE HWO. OUR FORECAST MINS ARE A BLEND OF CONTINUITY
AND STAT GUIDANCE.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
A LARGE AREA OF HIGH PRESSURE BUILDING DOWN FROM CANADA WILL BE
THE DOMINANT WX FEATURE FOR THE START OF THE EXTENDD PD. HOWEVER,
IT WILL BE REPLACED BY LOW PRESSURE AND AN H5 TROF FOR THE LATER
PORTION OF THE PD. ON FRIDAY, THE HIGH WILL BEGIN BUILDING IN AS
LOW PRESSURE MOVES OFF THE SERN CONUS COAST. THIS LOW WILL MOVE
WELL OFF THE ATLC COAST BEFORE RETROGRADING WWD TWD THE CANADIAN
MARITIMES EARLY NEXT WEEK. IT SHOULD BE NOTED THAT THE LATEST MDL
RUNS ARE NOW MUCH WEAKER AND FURTHER OFF THE COAST WITH THIS SYS
THAN PREV RUNS, ESPECIALLY THE GFS, AS IT MOVES NWD THEN NWWD.
WITH THE HIGH CONTROLLING THE WX THRU SUNDAY, EXPECT DRY CONDS
WITH SEASONAL TO SLIGHTLY ABV NRML TEMPS. THERE IS VERY HIGH
CONFIDENCE IN THIS PORTION OF THE FCST.
THEN THE MDLS BEGIN TO DIVERGE AND CONFIDENCE DROPS EARLY NEXT
WEEK. THE AFOREMENTIONED LOW PRESSURE SYSTEM MOVES TWD THE
CANADIAN MARITIMES AND THIS FEATURE COUPLED WITH ANOTHER LOW
DROPPING SEWD ACRS THE PLAINS WILL HELP CARVE OUT A LARGE TROF
OVER THE ERN CONUS. SEVERAL WAVES AND WEAK FRONTS WILL ROTATE THRU
THIS TROF THRU MIDWEEK AND BRING SHOTS OF PRECIP TO THE REGION.
HOWEVER, THE GFS,AS USUAL,IS WETTER THAN THE REST OF THE MDL
GUIDANCE, AND AT THIS MDL DISTANCE IT IS DIFFICULT TO PINPOINT
EXACTLY WHEN THE WETTEST PD WILL BE, BUT RIGHT NOW IT LOOKS TO BE
AT SOME POINT TUESDAY OR WEDNESDAY. ALSO, WHILE THE MDLS SEEM TO
HAVE SOME DECENT AGREEMENT ON THE GENERAL FEATURES, THEY DISAGREE
ON JUST HOW THEY INTERACT. SO, FOR NOW, WILL JUST KEEP SCHC AND
LOW CHC POPS.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
NO CEILINGS OR VISIBILITY LIMITATIONS ARE FORECAST THROUGH
TONIGHT. A MODERATE NORTH WIND IS EXPECTED TO DIMINISH LATER THIS
AFTERNOON BUT THEN PICK UP TOWARD THE END OF THE PERIOD.
LATEST HRRR AND HI RES NMMB SUPPORT THOUGHTS ABOUT A SEA BREEZE
STRUGGLING TO GET MUCH INLAND AND WE MAINTAINED IT TO THE EAST OF
KACY IN 12Z TAFS.
OUTLOOK...
VFR CONDITIONS ARE THRU THE WEEKEND WITH A LARGE AREA OF HIGH
PRESSURE BUILDING DOWN FROM CANADA. WINDS COULD BECOME GUSTY EACH
AFTERNOON THROUGH THE WEEKEND, WITH GUSTS GENERALLY AROUND 15-20
KNOTS.
&&
.MARINE...
WE CANCELLED THE SMALL CRAFT ADVISORY AS WINDS AND SEAS HAVE
DROPPED BELOW THE CRITERIA.
WINDS AND SEAS WILL PICK UP SOME TONIGHT WITH THE PASSAGE OF A
WEAK TROUGH, BUT THE PUSH BEHIND THE TROUGH DOESN`T LOOK AS
SUBSTANTIAL AS THE ONE THAT WAS BEHIND THE FRONT THAT CAME THROUGH
DURING THE NIGHT.
OUTLOOK...
HIGH PRESSURE WILL BUILD TO THE WEST OF THE WATERS FRIDAY THROUGH THE
WEEKEND. THE PRESSURE GRADIENT ACROSS THE WATERS SHOULD KEEP A
STEADY NORTH TO NORTHWEST WIND ACROSS THE AREA. IT IS POSSIBLE
THAT WIND GUSTS COULD APPROACH SMALL CRAFT ADVISORY DURING THIS
PERIOD, ESPECIALLY SATURDAY INTO SUNDAY.
&&
.FIRE WEATHER...
WE STILL THINK WINDS WILL FALL SHORT OF THE RED FLAG WARNING
CRITERIA AROUND OUR FORECAST AREA, SO WE WILL ISSUE A SPECIAL
WEATHER STATEMENT TO HIGHLIGHT THE DRY FINE FUELS AND THE LOW
RELATIVE HUMIDITY LEVELS THIS AFTERNOON.
A LOW DEPARTING OFF THE SOUTHEAST COAST MIGHT INCREASE THE GRADIENT
WITH A GREATER CHANCE FOR RED FLAG WARNING CONDITIONS ON FRIDAY AND
SATURDAY.
&&
.TIDES/COASTAL FLOODING...
THIS MORNING, DEPARTURES (WERE THEY TO REMAIN CONSTANT) SUPPORTED
THE POSSIBILITY OF JUST REACHING MINOR TIDAL FLOODING ALONG THE
COAST, RARITAN BAY AND LOWER DELAWARE BAY. THE OFS, HOWEVER,
SUGGEST THOSE DEPARTURES WOULD DIMINISH AS THE NORTH FLOW
DIMINISHES, AND SO WE THINK IT IS LIKELY THAT WE WILL AVOID ANY
FLOODING THIS EVENING. WE WILL MAINTAIN A MENTION IN THE HWO IN
THE INTEREST OF CAUTION.
AFTER THAT, THE COMBINATION OF THE APPROACHING SPRING TIDES WITH THE
FULL MOON AND THE EKMAN SPIRAL EFFECT FROM THE LIKELY AND
PREDOMINATELY NORTHERLY WINDS NEAR THE COAST MAY CAUSE MINOR TIDAL
FLOODING WITH THE EVENING AND OVERNIGHT HIGH TIDE CYCLES FROM FRIDAY
EVENING INTO THE WEEKEND. BY SATURDAY, WE WILL ONLY NEED DEPARTURES
OF ABOUT HALF A FOOT ABOVE NORMAL TO REACH THE CRITERIA. IN UPPER
DELAWARE BAY, THE TIDAL DELAWARE RIVER AND CHESAPEAKE BAY, THE
NORTHERLY FLOW COUPLED WITH NORMAL OR BELOW NORMAL FRESHWATER RUNOFF
SHOULD MITIGATE ANY TIDAL RELATED PROBLEMS.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...FREEZE WARNING FROM 3 AM TO 8 AM EDT FRIDAY FOR PAZ060>062.
NJ...FREEZE WARNING FROM 3 AM TO 8 AM EDT FRIDAY FOR NJZ007>010-
020>022-027.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...NIERENBERG
NEAR TERM...DELISI/GIGI
SHORT TERM...DELISI/GIGI
LONG TERM...NIERENBERG
AVIATION...DELISI/NIERENBERG
MARINE...DELISI/GIGI/NIERENBERG
FIRE WEATHER...DELISI
TIDES/COASTAL FLOODING...DELISI
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
909 AM EDT THU APR 5 2012
.SYNOPSIS...
A LARGE AREA OF HIGH PRESSURE WILL BUILD SOUTHWARD FROM CANADA
TODAY THROUGH THE WEEKEND. A SERIES OF FRONTAL BOUNDARIES ARE
EXPECTED TO AFFECT THE AREA LATE IN THE WEEKEND INTO THE MIDDLE OF
NEXT WEEK AS LOW PRESSURE MOVING THROUGH THE GREAT LAKES MERGES
WITH AN AREA OF LOW PRESSURE IN THE CANADIAN MARITIMES AND CARVES
OUT A TROUGH OVER THE EASTERN HALF OF THE NATION. SOME UNSETTLED
WEATHER IS POSSIBLE DURING THIS TIME.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NO BIG CHANGES MADE WITH THIS UPDATE. FORECAST ON TRACK. MORNING
12Z SOUNDINGS SUGGEST WE MAY BE A DEGREE OR TWO TOO LOW ON MAX
TEMPS. WE WILL SEE HOW THEY RESPOND THE REST OF MORNING AND MAKE
ANY NEEDED ADJUSTMENTS BY THE NEXT UPDATE. LATEST HRRR AND HI RES
NMMB SUPPORT THOUGHTS ABOUT A SEA BREEZE STRUGGLING TO GET MUCH
INLAND.
TODAY GENERALLY SHOULD BE A BENIGN WEATHER DAY WITH TEMPERATURES
A BIT MORE THAN 10 TO 15 DEGREES COOLER THAN WEDNESDAY THANKS TO
THE COLD FRONT THAT DROPPED THROUGH OUR AREA DURING THE NIGHT.
PERHAPS SOME HIGH CLOUDS WILL BE AROUND (LIKELY MORE SOUTH THAN
NORTH), BUT WE ARE CARRYING A SUNNY FORECAST. WINDS WILL START AS
MODERATE FROM THE NORTH, BUT AS A RATHER WEAK AND DRY TROUGH
APPROACHES THE AREA THIS AFTERNOON THEY ARE EXPECTED TO DIMINISH A
BIT. THE H925 FLOW IS IN OPPOSITION TO A SEA BREEZE LATER TODAY,
BUT IT IS ON THE LIGHT SIDE. WE HAVE A SEA BREEZE DEVELOPING, BUT
WE AREN`T CARRYING IT VERY FAR INLAND.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/...
WE ISSUED A FREEZE WARNING FOR THE COUNTIES WE ARE MOST CONFIDENT
WILL REACH FREEZING TEMPERATURES. THERE MAY BE AN EXPANSION LATER
TODAY IN PARTS OF DELMARVA AND THE LOCAL PHL METRO AREA.
SKIES ARE EXPECTED TO BE MAINLY CLEAR TONIGHT. AGAIN, HIGH CLOUDS
WILL BE MORE APPARENT NORTH THAN SOUTH. WINDS ARE EXPECTED TO
LIGHTEN IN A CLIMATOLOGICALLY NORMAL WAY AT FIRST, BUT THE PASSAGE
OF THE TROUGH TONIGHT MAY CAUSE THEM TO PICK UP A LITTLE OVERNIGHT
DESPITE SOME PARTIAL DECOUPLING. WE THEREFORE HAVE BEEN CAREFUL
ABOUT DROPPING THE BOTTOM OUT FROM TEMPERATURES. WE WILL MAINTAIN
THE POSSIBILITY OF FROST OR FREEZING TEMPERATURES OVER MANY
LOCATIONS IN THE HWO. OUR FORECAST MINS ARE A BLEND OF CONTINUITY
AND STAT GUIDANCE.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
A LARGE AREA OF HIGH PRESSURE BUILDING DOWN FROM CANADA WILL BE
THE DOMINANT WX FEATURE FOR THE START OF THE EXTENDD PD. HOWEVER,
IT WILL BE REPLACED BY LOW PRESSURE AND AN H5 TROF FOR THE LATER
PORTION OF THE PD. ON FRIDAY, THE HIGH WILL BEGIN BUILDING IN AS
LOW PRESSURE MOVES OFF THE SERN CONUS COAST. THIS LOW WILL MOVE
WELL OFF THE ATLC COAST BEFORE RETROGRADING WWD TWD THE CANADIAN
MARITIMES EARLY NEXT WEEK. IT SHOULD BE NOTED THAT THE LATEST MDL
RUNS ARE NOW MUCH WEAKER AND FURTHER OFF THE COAST WITH THIS SYS
THAN PREV RUNS, ESPECIALLY THE GFS, AS IT MOVES NWD THEN NWWD.
WITH THE HIGH CONTROLLING THE WX THRU SUNDAY, EXPECT DRY CONDS
WITH SEASONAL TO SLIGHTLY ABV NRML TEMPS. THERE IS VERY HIGH
CONFIDENCE IN THIS PORTION OF THE FCST.
THEN THE MDLS BEGIN TO DIVERGE AND CONFIDENCE DROPS EARLY NEXT
WEEK. THE AFOREMENTIONED LOW PRESSURE SYSTEM MOVES TWD THE
CANADIAN MARITIMES AND THIS FEATURE COUPLED WITH ANOTHER LOW
DROPPING SEWD ACRS THE PLAINS WILL HELP CARVE OUT A LARGE TROF
OVER THE ERN CONUS. SEVERAL WAVES AND WEAK FRONTS WILL ROTATE THRU
THIS TROF THRU MIDWEEK AND BRING SHOTS OF PRECIP TO THE REGION.
HOWEVER, THE GFS,AS USUAL,IS WETTER THAN THE REST OF THE MDL
GUIDANCE, AND AT THIS MDL DISTANCE IT IS DIFFICULT TO PINPOINT
EXACTLY WHEN THE WETTEST PD WILL BE, BUT RIGHT NOW IT LOOKS TO BE
AT SOME POINT TUESDAY OR WEDNESDAY. ALSO, WHILE THE MDLS SEEM TO
HAVE SOME DECENT AGREEMENT ON THE GENERAL FEATURES, THEY DISAGREE
ON JUST HOW THEY INTERACT. SO, FOR NOW, WILL JUST KEEP SCHC AND
LOW CHC POPS.
&&
.AVIATION /13Z THURSDAY THROUGH MONDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
NO CEILINGS OR VISIBILITY LIMITATIONS ARE FORECAST THROUGH
TONIGHT. A MODERATE NORTH WIND IS EXPECTED TO DIMINISH LATER THIS
AFTERNOON BUT THEN PICK UP TOWARD THE END OF THE PERIOD.
LATEST HRRR AND HI RES NMMB SUPPORT THOUGHTS ABOUT A SEA BREEZE
STRUGGLING TO GET MUCH INLAND AND WE MAINTAINED IT TO THE EAST OF
KACY IN 12Z TAFS.
OUTLOOK...
VFR CONDITIONS ARE THRU THE WEEKEND WITH A LARGE AREA OF HIGH
PRESSURE BUILDING DOWN FROM CANADA. WINDS COULD BECOME GUSTY EACH
AFTERNOON THROUGH THE WEEKEND, WITH GUSTS GENERALLY AROUND 15-20
KNOTS.
&&
.MARINE...
WE HAVE EXTENDED THE ADVISORY OVER THE OCEAN WATERS SOUTH OF
LITTLE EGG INLET UNTIL 1 PM AS SEAS AND EVEN WINDS WERE AT
CRITERIA AT BUOY9. ALL OTHER ADVISORIES HAD ENDED. WINDS AND SEAS
OVER THE SOUTHERN ATLANTIC WATERS ARE EXPECTED TO DROP BELOW THE
CRITERIA THROUGH THE MORNING. THEY WILL PICK UP SOME TONIGHT WITH
THE PASSAGE OF A WEAK TROUGH, BUT THE PUSH BEHIND THE TROUGH
DOESN`T LOOK AS SUBSTANTIAL AS THE ONE THAT WAS BEHIND THE FRONT
THAT CAME THROUGH DURING THE NIGHT.
OUTLOOK...
HIGH PRESSURE WILL BUILD TO THE WEST OF THE WATERS FRIDAY THROUGH THE
WEEKEND. THE PRESSURE GRADIENT ACROSS THE WATERS SHOULD KEEP A
STEADY NORTH TO NORTHWEST WIND ACROSS THE AREA. IT IS POSSIBLE
THAT WIND GUSTS COULD APPROACH SMALL CRAFT ADVISORY DURING THIS
PERIOD, ESPECIALLY SATURDAY INTO SUNDAY.
&&
.FIRE WEATHER...
WE STILL THINK WINDS WILL FALL SHORT OF THE RED FLAG WARNING
CRITERIA AROUND OUR FORECAST AREA, SO WE WILL ISSUE A SPECIAL
WEATHER STATEMENT TO HIGHLIGHT THE DRY FINE FUELS AND THE LOW
RELATIVE HUMIDITY LEVELS THIS AFTERNOON.
A LOW DEPARTING OFF THE SOUTHEAST COAST MIGHT INCREASE THE GRADIENT
WITH A GREATER CHANCE FOR RED FLAG WARNING CONDITIONS ON FRIDAY AND
SATURDAY.
&&
.TIDES/COASTAL FLOODING...
EARLY THIS MORNING, DEPARTURES (WERE THEY TO REMAIN CONSTANT)
SUPPORTED THE POSSIBILITY OF EVENING MINOR TIDAL FLOODING ALONG THE
COAST, RARITAN BAY AND LOWER DELAWARE BAY. THE OFS, HOWEVER, SUGGEST
THOSE DEPARTURES WOULD DIMINISH AS THE NORTH FLOW DIMINISHES, AND SO
WE THINK IT IS LIKELY THAT WE WILL AVOID ANY FLOODING THIS EVENING.
WE WILL MAINTAIN A MENTION IN THE HWO IN THE INTEREST OF CAUTION.
AFTER THAT, THE COMBINATION OF THE APPROACHING SPRING TIDES WITH THE
FULL MOON AND THE EKMAN SPIRAL EFFECT FROM THE LIKELY AND
PREDOMINATELY NORTHERLY WINDS NEAR THE COAST MAY CAUSE MINOR TIDAL
FLOODING WITH THE EVENING AND OVERNIGHT HIGH TIDE CYCLES FROM FRIDAY
EVENING INTO THE WEEKEND. BY SATURDAY, WE WILL ONLY NEED DEPARTURES
OF ABOUT HALF A FOOT ABOVE NORMAL TO REACH THE CRITERIA. IN UPPER
DELAWARE BAY, THE TIDAL DELAWARE RIVER AND CHESAPEAKE BAY, THE
NORTHERLY FLOW COUPLED WITH NORMAL OR BELOW NORMAL FRESHWATER RUNOFF
SHOULD MITIGATE ANY TIDAL RELATED PROBLEMS.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...FREEZE WARNING FROM 3 AM TO 8 AM EDT FRIDAY FOR PAZ060>062.
NJ...FREEZE WARNING FROM 3 AM TO 8 AM EDT FRIDAY FOR NJZ007>010-
020>022-027.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 PM EDT THIS AFTERNOON FOR
ANZ452>455.
&&
$$
SYNOPSIS...NIERENBERG
NEAR TERM...DELISI/GIGI
SHORT TERM...DELISI/GIGI
LONG TERM...NIERENBERG
AVIATION...DELISI/NIERENBERG
MARINE...DELISI/GIGI/NIERENBERG
FIRE WEATHER...DELISI
TIDES/COASTAL FLOODING...DELISI
AREA FORECAST DISCUSSION
NWS GOODLAND KS
905 AM MDT THU APR 5 2012
.UPDATE...
ISSUED AT 902 AM MDT THU APR 5 2012
UPDATED TO CANCEL THE DENSE FOG ADVISORY SINCE FOG HAS DIMINISHED
AND VISIBILITIES HAVE IMPROVED ACROSS THE AREA.
UPDATE ISSUED AT 547 AM MDT THU APR 5 2012
COMPLETED AN UPDATE NOT TOO LONG AGO. MAIN REASON FOR UPDATE WAS
TO REDEFINE DENSE FOG ADVISORY AREA. OBSERVATIONS SHOWING DENSE
FOG HAVE STAYED ROUGHLY ALONG AND WEST OF THE COLORADO BORDER. THE
HRRR FOLLOWED BY THE RUC WAS DOING VERY WELL WITH THIS. SO
CANCELLED THE EASTERN MOST ROW OF COUNTIES THAT WERE IN THE
ADVISORY. USED THE COMBINATION OF REALITY COMBINED WITH THE
MESOSCALE MODELS TO ADJUST THE HOURLY GRIDS THROUGH THE MORNING
HOURS.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 357 AM MDT THU APR 5 2012
FORECAST PROBLEMS WILL BE EXTENT OF FOG/STRATUS THROUGH TOMORROW
NIGHT AND ITS AFFECTS ON TEMPERATURES...CHANCES OF
CONVECTION/PRECIPITATION THROUGH FRIDAY NIGHT...AND WINDS FRIDAY
INTO SATURDAY. SATELLITE SHOWING AN AMPLIFIED/AMPLIFYING PATTERN
OVER THE NORTHERN HEMISPHERE WITH A SERIES OF TROUGHS FROM THE
PACIFIC INTO THE WESTERN ATLANTIC. SLOW MOVING UPPER LOW THAT BROUGHT
A LOT OF PRECIPITATION HAS FINALLY MOVED WELL EAST OF THE AREA. NEXT
UPPER TROUGH TO AFFECT OUR WEATHER IS DEEPENING ALONG THE WEST COAST
AT THIS TIME. SATELLITE/UPPER AIR WOULD INDICATE A LOT OF COLD AIR
WITH THIS SYSTEM.
AT JET LEVEL THE ECMWF AND NAM WERE DOING A LITTLE BETTER WITH THE
JET ASSOCIATED WITH THE NEW WESTERN TROUGH. THROUGH 06Z SATELLITE
AND UPPER AIR DATA SHOWED THAT ALL THE MODELS WERE CLOSE BUT THE
ECMWF AND NAM WERE DOING A LITTLE BETTER THAN THE REST. THE NAM AND
ECMWF WERE DOING WELL WITH THE SURFACE PRESSURE/WIND FIELD. THE
ECMWF...CANADIAN AND GFS WERE DOING THE BEST ON THE LOW LEVEL
THERMAL FIELD.
TODAY/TONIGHT...INITIAL PROBLEM WILL BE THE DENSE FOG ADVISORY IN
AFFECT AND HOW LONG THE STRATUS AND FOG LAST. WILL MONITOR TRENDS
FOR AS LONG AS POSSIBLE AND MAKE ANY ADJUSTMENTS IN THE ADVISORY OR
FOG AREA AS NEEDED. AT THIS TIME THE DENSE FOG HAS STAYED CONFINED
TO ALONG AND WEST OF THE COLORADO BORDER. GUIDANCE IS STARTING TO
HINT THIS WILL BE THE CASE. WILL CONTINUE TO MONITOR.
AM CONCERNED ABOUT THE EASTERN HALF OF THE AREA WARMING UP VERY MUCH
DUE TO POSSIBILITY OF CLOUDS LASTING A LONG TIME PLUS THE PREVAILING
EASTERLY UPSLOPE WINDS THROUGH THE DAY. LOWERED THE MAXES SOME BUT
STILL MAY NOT BE ENOUGH.
INTERESTING FORECAST FOR TONIGHT. MODELS STILL IN AGREEMENT IN
BRINGING IN AT THE VERY LEAST A WIDESPREAD STRATUS DECK. POSSIBLE
THAT THE AREA OF FOG/DENSE FOG COULD BE EVEN LARGER THAN THIS
MORNINGS. 06Z NAM EVEN MORE AGGRESSIVE IN DOING THIS THAN THE EARLIER
GUIDANCE. CURRENT PACKAGE HAS -SHRA/ELEVATED -TSRA FOR LATER TONIGHT.
MAIN UPPER JET REMAINS MUCH FURTHER WEST BY 12Z AS SHOWN YESTERDAY.
MODELS HINTING AT A WEAK LEFT FRONT QUADRANT OF THE UPPER AFFECTING
THE FAR WESTERN PORTION OF THE AREA AFTER 06Z. MODELS TENDED TO BE
TOO FAR EAST INITIALLY WITH THE MAIN AXIS. THINKING THAT THE MODELS
MAY BE TOO PROGRESSIVE WITH THE UPPER TROUGH AND ASSOCIATED BELIEVE
THE JET LIFT WILL BE A LITTLE FURTHER WEST THAN CURRENTLY INDICATED.
THERE IS WARM ADVECTION IN THE MID LAYERS. HOWEVER...SATELLITE AND
UPPER AIR ANALYSIS IS SHOWING A VERY DEEP AND DRY LAYER IN THE MID
LEVELS. LATEST MODEL GUIDANCE HAS SOME CINH IN PLACE AND ALSO NO
ELEVATED CAPE. GFS/NAM MODEL SOUNDINGS BOTH IN AGREEMENT THAT WILL
HAVE A SHALLOW SATURATED LOW LAYER WITH VERY DRY AIR ABOVE IT. SO
EVEN IF IT WERE UNSTABLE ENOUGH DOUBT THAT PARCELS COULD BECOME
SATURATED. SREF GIVES LITTLE TO NO PROBABILITY FOR MEASURABLE OR
CONVECTIVE PRECIPITATION. CONSIDERING WHAT THE SOUNDINGS ARE
SHOWING THINKING THEY ARE GENERATING DRIZZLE. AFTER SAYING ALL
THAT...WILL PUT IN AREAS OF FOG WITH PATCHY DRIZZLE. BECAUSE OF THE
INCREASING MOISTURE...WINDS AND CLOUD COVER WARMED MINS UP AND IT IS
POSSIBLE THAT I STILL MAY NOT BE WARM ENOUGH.
FRIDAY/FRIDAY NIGHT...MODELS/HPC GENERATE/PUT LIGHT QPF ACROSS THE
AREA DURING THE DAY...ESPECIALLY EARLY IN THE DAY. AGAIN THE SAME
REASON/ARGUMENT FOR THE WEATHER/CHANCE OF PRECIPITATION APPLIES TO
THE MORNING HOURS HERE. WILL CONTINUE THE AREAS OF FOG AND PATCHY
DRIZZLE.
MODELS DIFFER ON THE POSITION OF THE MAIN JET AND ALL IMPORTANT
LEFT FRONT QUADRANT. MODEL CLUSTERING WOULD TEND TO FAVOR TO START
THE LEFT FRONT QUADRANT NEAR THE SOUTHERN/SOUTHWEST PORTION OF THE
AREA AT 18Z AND THEN PROGRESS IT NORTH THROUGH THE AFTERNOON WITH
THE MAIN JET LIFT TO THE NORTH OF THE AREA BY LATE AFTERNOON. THE
NAM IS FURTHER SOUTH THAN ANYONE AND A LITTLE MORE FAVORABLE. THIS
CONTINUES INTO THE MIDDLE OF THE NIGHT. DRY LINE IS FURTHER WEST
THAN SHOWN YESTERDAY WHICH HAS BEEN THE TREND THE LAST FEW DAYS.
MODEL SOUNDINGS ARE NOT TERRIBLY MOIST. HOWEVER THERE LOOKS TO BE A
NARROW INSTABILITY AXIS NEAR THE COLORADO BORDER WITH NO CAP. WILL
HAVE THE JET AND DRY LINE CLOSE BY ALONG WITH INCOMING SHORTWAVE
TROUGH. SO ADJUSTED THE SLIGHT CHANCE OF THUNDERSTORMS TO NEAR THE
COLORADO BORDER/INSTABILITY AXIS. LIFT AND INSTABILITY SHIFT EAST
DURING THE NIGHT. ALSO FRONT MOVES THROUGH THE EASTERN HALF AFTER
06Z. SO TRANSITIONED THE SLIGHT CHANCE TO CHANCE POPS TO THE EAST
AS THE NIGHT PROGRESSES.
AGAIN THE MAIN PLAYER IN HOW WARM IT GETS WILL BE HOW LONG STRATUS
AND FOG LAST. FROM YESTERDAY...DRYLINE AND GREATER LOW LEVEL
MOISTURE/CLOUD COVER ARE FURTHER WEST THAN YESTERDAY. MODELS
CONSEQUENTLY HAVE LOWERED MAXES FROM YESTERDAY. SO I CONTINUED TO
PULL WARMER TEMPERATURES FURTHER TO THE WEST. FRONT LOOKS TO MOVE
THROUGH DURING THE LATE EVENING INTO THE OVERNIGHT HOURS.
WINDS BEHIND THE FRONT COULD INCREASE INTO THE BREEZY TO WINDY
CATEGORY FOR A BRIEF TIME PERIOD.
SATURDAY/SATURDAY NIGHT...STRONGEST WINDS LOOK TO BE BEFORE SUNRISE.
LOWER DEWPOINTS LOOK TO BE ADVECTED IN AS WELL. IT IS STILL TOO FAR
OUT TO PUT ANY FIRE WEATHER HIGHLIGHT EVEN IF I WANTED TO. BUT
DESPITE THE FAVORABLE WINDS AND DEWPOINTS BELIEVE THE FUEL MOISTURE
WILL STILL BE RATHER HIGH AFTER THE PREVIOUS RAIN.
WINDS DECOUPLE AND BECOME LIGHT SO MINS WILL MUCH COLDER THAN THEY
HAVE BEEN RECENTLY. POSSIBLE THAT SOME LOCATIONS COULD GET TO NEAR
FREEZING.
THANKS TO ALL THAT COLLABORATED.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 357 AM MDT THU APR 5 2012
A FRONT WILL REMAIN STALLED SOUTH AND WEST OF THE CWA THROUGH THE
EXTENDED PERIOD WITH EASTERLY FLOW IN PLACE OVER NW KS AND SW
NEBRASKA. WEST OF STATIONARY FRONT WILL SEE SOUTHERLY FLOW WITH
WARMER TEMPS ALOFT. RESULT WILL BE GRADIENT IN TEMPS FROM WEST TO
EAST WITH WARMEST OVER EASTERN COLORADO AND COOLER EAST. NOT A LOT
OF CONFIDENCE IN TEMP FORECAST THROUGH THE EXTENDED PERIOD WITH THE
POTENTIAL FOR CLOUD COVER TO LIMIT NORMAL DIURNAL WARMING/COOLING
TRENDS. FOR NOW FORECAST SHOWS SEASONABLY MILD TEMPS IN THE
60S...NEAR 70 IN EASTERN COLORADO.
H5 RIDGE ALOFT WILL GENERALLY KEEP STABLE AIR MASS AND DRY
CONDITIONS EXPECTED THROUGH TUESDAY NIGHT. BY WEDNESDAY ISENTROPIC
UPGLIDE AND DEEP MOISTURE ADVECTION WILL OVERSPREAD THE AREA AS A
TROUGH DEEPENS ACROSS THE WESTERN US. WITH LARGE SCALE SUBSIDENCE
ALOFT AND STABLE AIRMASS IN PLACE IM NOT VERY CONFIDENT WE WILL SEE
MUCH IN THE WAY OF MEASUREABLE PRECIPITATION WEDNESDAY. GFS CONTINUES
TO SHOW DEEP MOISTURE IN PLACE ALONG WITH ISENTROPIC UPGLIDE...SO
SOME SHOWER ACTIVITY CANT BE RULED OUT WED. THUNDERSTORMS ALSO CANT
BE RULED OUT WED AFTERNOON ACROSS THE SOUTH AND WEST WHERE ELEVATED
CAPE IS CURRENTLY ADVERTISED ON BY GFS NEAR SURFACE BAROCLINIC ZONE.
FROM EXPERIENCE THIS SEEMS TO BE MORE OF A DRIZZLE/FOG PATTERN
ACROSS MUCH OF THE CWA...THOUGH THE GFS SOLUTION CANT BE DISCOUNTED.
THERE IS ENOUGH UNCERTAINTY AT THIS RANGE THAT I LEFT SLIGHT CHANCE
POPS IN PLACE WED THIS FORECAST CYCLE.
BY WED NIGHT/THURSDAY A NEGATIVELY TILTED UPPER TROUGH OVER THE
WESTERN US WILL BEGIN TO MOVE TOWARDS THE CWA...WITH A GREAT DEAL OF
SPREAD BETWEEN GUIDANCE ON THE TIMING OF THIS FEATURE AND HOW IT
EVOLVES. 00Z ECMWF IS MUCH SLOWER...STRONGER...AND FURTHER SOUTH.
THE GFS IS MORE PROGRESSIVE AND FURTHER NORTH. CONSIDERING THE
SPREAD IN GUIDANCE SLIGHT CHANCE POPS SEEMED LIKE A GOOD FIRST
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 547 AM MDT THU APR 5 2012
DIFFICULT SET OF TAFS. HAVE BEEN WAITING ON WHAT TO DO WITH AREAS
OF FOG/PATCHY DENSE FOG THAT HAVE DEVELOPED ACROSS THE AREA. DENSE
FOG HAD STAYED TO THE WEST OF KGLD. THE RUC AND ESPECIALLY THE
HRRR KEEP THE DENSE FOG EAST OF KGLD AND FOLLOWED THEM FOR THIS
TAF ISSUANCE. SO FOR BOTH TAF SITES HAVE MVFR CONDITIONS UNTIL
EARLY AFTERNOON. EXPECT FOG AND STRATUS TO REDEVELOP LATE THIS
EVENING INTO THE OVERNIGHT HOURS. CONDITIONS START OUT MVFR BUT
EXPECT CONDITIONS AT BOTH SITES TO DROP TO LIFR TO IFR CONDITIONS
AFTER 06Z.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
KS...NONE.
NE...NONE.
&&
$$
UPDATE...LOCKHART
SHORT TERM...BULLER
LONG TERM....DR
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
555 AM MDT THU APR 5 2012
.UPDATE...
ISSUED AT 547 AM MDT THU APR 5 2012
COMPLETED AN UPDATE NOT TOO LONG AGO. MAIN REASON FOR UPDATE WAS
TO REDEFINE DENSE FOG ADVISORY AREA. OBSERVATIONS SHOWING DENSE
FOG HAVE STAYED ROUGHLY ALONG AND WEST OF THE COLORADO BORDER. THE
HRRR FOLLOWED BY THE RUC WAS DOING VERY WELL WITH THIS. SO
CANCELLED THE EASTERN MOST ROW OF COUNTIES THAT WERE IN THE
ADVISORY. USED THE COMBINATION OF REALITY COMBINED WITH THE
MESOSCALE MODELS TO ADJUST THE HOURLY GRIDS THROUGH THE MORNING
HOURS.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 357 AM MDT THU APR 5 2012
FORECAST PROBLEMS WILL BE EXTENT OF FOG/STRATUS THROUGH TOMORROW
NIGHT AND ITS AFFECTS ON TEMPERATURES...CHANCES OF
CONVECTION/PRECIPITATION THROUGH FRIDAY NIGHT...AND WINDS FRIDAY
INTO SATURDAY. SATELLITE SHOWING AN AMPLIFIED/AMPLIFYING PATTERN
OVER THE NORTHERN HEMISPHERE WITH A SERIES OF TROUGHS FROM THE
PACIFIC INTO THE WESTERN ATLANTIC. SLOW MOVING UPPER LOW THAT BROUGHT
A LOT OF PRECIPITATION HAS FINALLY MOVED WELL EAST OF THE AREA. NEXT
UPPER TROUGH TO AFFECT OUR WEATHER IS DEEPENING ALONG THE WEST COAST
AT THIS TIME. SATELLITE/UPPER AIR WOULD INDICATE A LOT OF COLD AIR
WITH THIS SYSTEM.
AT JET LEVEL THE ECMWF AND NAM WERE DOING A LITTLE BETTER WITH THE
JET ASSOCIATED WITH THE NEW WESTERN TROUGH. THROUGH 06Z SATELLITE
AND UPPER AIR DATA SHOWED THAT ALL THE MODELS WERE CLOSE BUT THE
ECMWF AND NAM WERE DOING A LITTLE BETTER THAN THE REST. THE NAM AND
ECMWF WERE DOING WELL WITH THE SURFACE PRESSURE/WIND FIELD. THE
ECMWF...CANADIAN AND GFS WERE DOING THE BEST ON THE LOW LEVEL
THERMAL FIELD.
TODAY/TONIGHT...INITIAL PROBLEM WILL BE THE DENSE FOG ADVISORY IN
AFFECT AND HOW LONG THE STRATUS AND FOG LAST. WILL MONITOR TRENDS
FOR AS LONG AS POSSIBLE AND MAKE ANY ADJUSTMENTS IN THE ADVISORY OR
FOG AREA AS NEEDED. AT THIS TIME THE DENSE FOG HAS STAYED CONFINED
TO ALONG AND WEST OF THE COLORADO BORDER. GUIDANCE IS STARTING TO
HINT THIS WILL BE THE CASE. WILL CONTINUE TO MONITOR.
AM CONCERNED ABOUT THE EASTERN HALF OF THE AREA WARMING UP VERY MUCH
DUE TO POSSIBILITY OF CLOUDS LASTING A LONG TIME PLUS THE PREVAILING
EASTERLY UPSLOPE WINDS THROUGH THE DAY. LOWERED THE MAXES SOME BUT
STILL MAY NOT BE ENOUGH.
INTERESTING FORECAST FOR TONIGHT. MODELS STILL IN AGREEMENT IN
BRINGING IN AT THE VERY LEAST A WIDESPREAD STRATUS DECK. POSSIBLE
THAT THE AREA OF FOG/DENSE FOG COULD BE EVEN LARGER THAN THIS
MORNINGS. 06Z NAM EVEN MORE AGGRESSIVE IN DOING THIS THAN THE EARLIER
GUIDANCE. CURRENT PACKAGE HAS -SHRA/ELEVATED -TSRA FOR LATER TONIGHT.
MAIN UPPER JET REMAINS MUCH FURTHER WEST BY 12Z AS SHOWN YESTERDAY.
MODELS HINTING AT A WEAK LEFT FRONT QUADRANT OF THE UPPER AFFECTING
THE FAR WESTERN PORTION OF THE AREA AFTER 06Z. MODELS TENDED TO BE
TOO FAR EAST INITIALLY WITH THE MAIN AXIS. THINKING THAT THE MODELS
MAY BE TOO PROGRESSIVE WITH THE UPPER TROUGH AND ASSOCIATED BELIEVE
THE JET LIFT WILL BE A LITTLE FURTHER WEST THAN CURRENTLY INDICATED.
THERE IS WARM ADVECTION IN THE MID LAYERS. HOWEVER...SATELLITE AND
UPPER AIR ANALYSIS IS SHOWING A VERY DEEP AND DRY LAYER IN THE MID
LEVELS. LATEST MODEL GUIDANCE HAS SOME CINH IN PLACE AND ALSO NO
ELEVATED CAPE. GFS/NAM MODEL SOUNDINGS BOTH IN AGREEMENT THAT WILL
HAVE A SHALLOW SATURATED LOW LAYER WITH VERY DRY AIR ABOVE IT. SO
EVEN IF IT WERE UNSTABLE ENOUGH DOUBT THAT PARCELS COULD BECOME
SATURATED. SREF GIVES LITTLE TO NO PROBABILITY FOR MEASURABLE OR
CONVECTIVE PRECIPITATION. CONSIDERING WHAT THE SOUNDINGS ARE
SHOWING THINKING THEY ARE GENERATING DRIZZLE. AFTER SAYING ALL
THAT...WILL PUT IN AREAS OF FOG WITH PATCHY DRIZZLE. BECAUSE OF THE
INCREASING MOISTURE...WINDS AND CLOUD COVER WARMED MINS UP AND IT IS
POSSIBLE THAT I STILL MAY NOT BE WARM ENOUGH.
FRIDAY/FRIDAY NIGHT...MODELS/HPC GENERATE/PUT LIGHT QPF ACROSS THE
AREA DURING THE DAY...ESPECIALLY EARLY IN THE DAY. AGAIN THE SAME
REASON/ARGUMENT FOR THE WEATHER/CHANCE OF PRECIPITATION APPLIES TO
THE MORNING HOURS HERE. WILL CONTINUE THE AREAS OF FOG AND PATCHY
DRIZZLE.
MODELS DIFFER ON THE POSITION OF THE MAIN JET AND ALL IMPORTANT
LEFT FRONT QUADRANT. MODEL CLUSTERING WOULD TEND TO FAVOR TO START
THE LEFT FRONT QUADRANT NEAR THE SOUTHERN/SOUTHWEST PORTION OF THE
AREA AT 18Z AND THEN PROGRESS IT NORTH THROUGH THE AFTERNOON WITH
THE MAIN JET LIFT TO THE NORTH OF THE AREA BY LATE AFTERNOON. THE
NAM IS FURTHER SOUTH THAN ANYONE AND A LITTLE MORE FAVORABLE. THIS
CONTINUES INTO THE MIDDLE OF THE NIGHT. DRY LINE IS FURTHER WEST
THAN SHOWN YESTERDAY WHICH HAS BEEN THE TREND THE LAST FEW DAYS.
MODEL SOUNDINGS ARE NOT TERRIBLY MOIST. HOWEVER THERE LOOKS TO BE A
NARROW INSTABILITY AXIS NEAR THE COLORADO BORDER WITH NO CAP. WILL
HAVE THE JET AND DRY LINE CLOSE BY ALONG WITH INCOMING SHORTWAVE
TROUGH. SO ADJUSTED THE SLIGHT CHANCE OF THUNDERSTORMS TO NEAR THE
COLORADO BORDER/INSTABILITY AXIS. LIFT AND INSTABILITY SHIFT EAST
DURING THE NIGHT. ALSO FRONT MOVES THROUGH THE EASTERN HALF AFTER
06Z. SO TRANSITIONED THE SLIGHT CHANCE TO CHANCE POPS TO THE EAST
AS THE NIGHT PROGRESSES.
AGAIN THE MAIN PLAYER IN HOW WARM IT GETS WILL BE HOW LONG STRATUS
AND FOG LAST. FROM YESTERDAY...DRYLINE AND GREATER LOW LEVEL
MOISTURE/CLOUD COVER ARE FURTHER WEST THAN YESTERDAY. MODELS
CONSEQUENTLY HAVE LOWERED MAXES FROM YESTERDAY. SO I CONTINUED TO
PULL WARMER TEMPERATURES FURTHER TO THE WEST. FRONT LOOKS TO MOVE
THROUGH DURING THE LATE EVENING INTO THE OVERNIGHT HOURS.
WINDS BEHIND THE FRONT COULD INCREASE INTO THE BREEZY TO WINDY
CATEGORY FOR A BRIEF TIME PERIOD.
SATURDAY/SATURDAY NIGHT...STRONGEST WINDS LOOK TO BE BEFORE SUNRISE.
LOWER DEWPOINTS LOOK TO BE ADVECTED IN AS WELL. IT IS STILL TOO FAR
OUT TO PUT ANY FIRE WEATHER HIGHLIGHT EVEN IF I WANTED TO. BUT
DESPITE THE FAVORABLE WINDS AND DEWPOINTS BELIEVE THE FUEL MOISTURE
WILL STILL BE RATHER HIGH AFTER THE PREVIOUS RAIN.
WINDS DECOUPLE AND BECOME LIGHT SO MINS WILL MUCH COLDER THAN THEY
HAVE BEEN RECENTLY. POSSIBLE THAT SOME LOCATIONS COULD GET TO NEAR
FREEZING.
THANKS TO ALL THAT COLLABORATED.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 357 AM MDT THU APR 5 2012
A FRONT WILL REMAIN STALLED SOUTH AND WEST OF THE CWA THROUGH THE
EXTENDED PERIOD WITH EASTERLY FLOW IN PLACE OVER NW KS AND SW
NEBRASKA. WEST OF STATIONARY FRONT WILL SEE SOUTHERLY FLOW WITH
WARMER TEMPS ALOFT. RESULT WILL BE GRADIENT IN TEMPS FROM WEST TO
EAST WITH WARMEST OVER EASTERN COLORADO AND COOLER EAST. NOT A LOT
OF CONFIDENCE IN TEMP FORECAST THROUGH THE EXTENDED PERIOD WITH THE
POTENTIAL FOR CLOUD COVER TO LIMIT NORMAL DIURNAL WARMING/COOLING
TRENDS. FOR NOW FORECAST SHOWS SEASONABLY MILD TEMPS IN THE
60S...NEAR 70 IN EASTERN COLORADO.
H5 RIDGE ALOFT WILL GENERALLY KEEP STABLE AIR MASS AND DRY
CONDITIONS EXPECTED THROUGH TUESDAY NIGHT. BY WEDNESDAY ISENTROPIC
UPGLIDE AND DEEP MOISTURE ADVECTION WILL OVERSPREAD THE AREA AS A
TROUGH DEEPENS ACROSS THE WESTERN US. WITH LARGE SCALE SUBSIDENCE
ALOFT AND STABLE AIRMASS IN PLACE IM NOT VERY CONFIDENT WE WILL SEE
MUCH IN THE WAY OF MEASUREABLE PRECIPITATION WEDNESDAY. GFS CONTINUES
TO SHOW DEEP MOISTURE IN PLACE ALONG WITH ISENTROPIC UPGLIDE...SO
SOME SHOWER ACTIVITY CANT BE RULED OUT WED. THUNDERSTORMS ALSO CANT
BE RULED OUT WED AFTERNOON ACROSS THE SOUTH AND WEST WHERE ELEVATED
CAPE IS CURRENTLY ADVERTISED ON BY GFS NEAR SURFACE BAROCLINIC ZONE.
FROM EXPERIENCE THIS SEEMS TO BE MORE OF A DRIZZLE/FOG PATTERN
ACROSS MUCH OF THE CWA...THOUGH THE GFS SOLUTION CANT BE DISCOUNTED.
THERE IS ENOUGH UNCERTAINTY AT THIS RANGE THAT I LEFT SLIGHT CHANCE
POPS IN PLACE WED THIS FORECAST CYCLE.
BY WED NIGHT/THURSDAY A NEGATIVELY TILTED UPPER TROUGH OVER THE
WESTERN US WILL BEGIN TO MOVE TOWARDS THE CWA...WITH A GREAT DEAL OF
SPREAD BETWEEN GUIDANCE ON THE TIMING OF THIS FEATURE AND HOW IT
EVOLVES. 00Z ECMWF IS MUCH SLOWER...STRONGER...AND FURTHER SOUTH.
THE GFS IS MORE PROGRESSIVE AND FURTHER NORTH. CONSIDERING THE
SPREAD IN GUIDANCE SLIGHT CHANCE POPS SEEMED LIKE A GOOD FIRST
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING)
ISSUED AT 547 AM MDT THU APR 5 2012
DIFFICULT SET OF TAFS. HAVE BEEN WAITING ON WHAT TO DO WITH AREAS
OF FOG/PATCHY DENSE FOG THAT HAVE DEVELOPED ACROSS THE AREA. DENSE
FOG HAD STAYED TO THE WEST OF KGLD. THE RUC AND ESPECIALLY THE
HRRR KEEP THE DENSE FOG EAST OF KGLD AND FOLLOWED THEM FOR THIS
TAF ISSUANCE. SO FOR BOTH TAF SITES HAVE MVFR CONDITIONS UNTIL
EARLY AFTERNOON. EXPECT FOG AND STRATUS TO REDEVELOP LATE THIS
EVENING INTO THE OVERNIGHT HOURS. CONDITIONS START OUT MVFR BUT
EXPECT CONDITIONS AT BOTH SITES TO DROP TO LIFR TO IFR CONDITIONS
AFTER 06Z.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
CO...DENSE FOG ADVISORY UNTIL 10 AM MDT THIS MORNING FOR COZ090>092.
KS...DENSE FOG ADVISORY UNTIL 10 AM MDT /11 AM CDT/ THIS MORNING FOR
KSZ001-013-027-041.
NE...DENSE FOG ADVISORY UNTIL 10 AM MDT THIS MORNING FOR NEZ079.
&&
$$
UPDATE...BULLER
SHORT TERM...BULLER
LONG TERM....DR
AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS DULUTH MN
629 AM CDT THU APR 5 2012
.AVIATION.../12Z TAF ISSUANCE/
MARGINAL LOW-LEVEL WIND SHEAR IS EXPECTED EARLY THIS MORNING AND
THEN AGAIN LATE TONIGHT. OTHERWISE VFR CONDITIONS ARE EXPECTED
ACROSS THE NORTHLAND THROUGH THE TAF PERIOD.
&&
.PREV DISCUSSION... /ISSUED 317 AM CDT THU APR 5 2012/
SHORT TERM...TODAY THROUGH FRIDAY.
AN UPPER LEVEL RIDGE AND SURFACE HIGH TO THE EAST/NORTHEAST WILL
PROVIDE PLENTY OF SUNSHINE AND DRY WEATHER THROUGH THE PERIOD.
IT WILL BE A BIT COOLER TODAY WITH ONSHORE WINDS CONTINUING AROUND
LAKE SUPERIOR. HIGHS WILL RANGE FROM 55 TO 60 WELL IN OUR
WESTERN/SOUTHERN ZONES...TO 45 TO 50 CLOSER TO LAKE SUPERIOR.
CLEAR SKIES TONIGHT AND LIGHT WINDS OVER CENTRAL AND EASTERN ZONES
WILL ALLOW TEMPERATURES TO DROP INTO THE TWENTIES FOR MOST AREAS.
MOSTLY SUNNY SKIES ON FRIDAY AND INCREASING SOUTHEASTERLY WINDS
WILL ALLOW TEMPS TO WARM INTO THE UPPER FIFTIES TO LOWER SIXTIES
WELL INLAND FROM LAKE SUPERIOR...WITH AREAS CLOSER TO LAKE
SUPERIOR COOLER DUE TO CONTINUED ONSHORE WINDS. THE SOUTH SHORE
WILL REACH THE MID FIFTIES TO AROUND SIXTY AS WINDS TURN MORE OUT
OF THE SOUTHEAST THROUGH THE DAY.
LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY.
A RIDGE OF HIGH PRESSURE OVER THE GREAT LAKES WILL MOVE OFF TO THE
EAST AND GIVE WAY TO A LOW PRESSURE SYSTEM OVER THE PLAINS WHICH IS
PROGGED TO LIFT NEWD OVER NWRN ONTARIO BY SATURDAY NIGHT. A TRAILING
COLD FRONT WILL SWEEP EWD ACROSS THE UPPER MIDWEST SATURDAY INTO
SATURDAY NIGHT...BRINGING A CHANCE OF SHOWERS AND POSSIBLY SOME
THUNDERSTORMS TO THE NORTHLAND. COOL AND BLUSTERY WEATHER WITH A
CHANCE OF RAIN/SNOW SHOWERS IS THEN EXPECTED FOR SUNDAY INTO MONDAY
AS THE PARENT UPPER LEVEL TROUGH MOVES ACROSS THE REGION. ANOTHER
RIDGE OF HIGH PRESSURE FROM CANADA WILL BUILD BACK OVER THE UPPER
MIDWEST...RESULTING IN DRIER CONDITIONS AND SEASONAL TEMPS.
AVIATION.../06Z TAF ISSUANCE/
THE RUC13 925MB WINDS AND NAM12 1000MB-950MB WINDS INDICATE SOUTHEAST
WINDS OF UP TO 30 KNOTS OVERNIGHT SO INCLUDED WIND SHEAR AT 1K AGL
THROUGH 12Z. VAD WIND PROFILES FROM DLH HAVE BEEN CONSISTENT THE
PAST TWO HOURS WITH 30 KNOT WINDS FROM THE SOUTHEAST ABOVE THE SURFACE.
OTHERWISE...VFR CONDITIONS WILL CONTINUE THROUGH THE TAF PERIOD.
&&
.POINT TEMPS/POPS...
DLH 50 28 56 34 / 0 0 0 10
INL 56 24 60 36 / 0 0 0 10
BRD 59 31 62 40 / 0 0 0 20
HYR 58 22 62 33 / 0 0 0 10
ASX 48 25 58 34 / 0 0 0 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...SMALL CRAFT ADVISORY UNTIL 10 PM CDT THIS EVENING FOR LSZ144-145.
&&
$$
AVIATION...BERDES
AREA FORECAST DISCUSSION
NWS GLASGOW MT
926 AM MDT THU APR 5 2012
.SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH SATURDAY...
GFS SEEMS TO HAVE A BETTER HANDLE ON CURRENT CONDITIONS THAN THE 12Z
NAM. 12Z HRRR MODEL ALSO SHOWING A DECENT HANDLE ON THINGS BUT SEEMS
TO BE TOO DRY WITH ECHOES OVER THE AREA.
INCREASED POPS FOR TODAY...ADDING MENTION OF SNOW LIKELY FOR SW
PHILLIPS COUNTY. LIGHT TO MODERATE SNOW HAS ALREADY BEEN REPORTED IN
KLWT AND KHVR THIS MORNING. REST OF FORECAST LOOKED GOOD. JAMBA
PREVIOUS DISCUSSION...
A MAJOR WINTER STORM OR BLIZZARD IS POSSIBLE FRIDAY AND SATURDAY
ACROSS NORTHEAST MONTANA. A BLIZZARD WATCH HAS BEEN ISSUED FOR THE
WESTERN HALF OF THE FORECAST AREA FOR FRIDAY THROUGH SATURDAY. THE
EASTERN HALF OF THE FORECAST AREA MAY NEED A WINTER WEATHER
HEADLINE FOR FRIDAY NIGHT AND SATURDAY.
A COLD FRONT CURRENTLY MOVING THROUGH EASTERN MONTANA IS EXPECTED
TO BECOME STATIONARY ALONG THE NORTH DAKOTA BORDER THIS MORNING AS
THE FRONT BECOMES PARALLEL TO THE SOUTHERLY FLOW ALOFT. DEEP UPPER
TROUGH/LOW OVER THE WESTERN U.S AND CANADA WILL MOVE INLAND TODAY
AND START IMPACTING THE FORECAST AREA LATE TONIGHT. THE TROUGH
WILL SPLIT TODAY WITH THE NORTHERN BRANCH BECOMING A CLOSED UPPER
LOW OVER NORTHERN ALBERTA WHILE THE SOUTHERN BRANCH TROUGH WILL
MOVE INTO MONATANA TONIGHT AND FRIDAY.
A COMBINATION OF MID AND UPPER LEVEL PACIFIC MOISTURE AND LOW
LEVEL GULF OF MEXICO MOISTURE WILL START MOVING INTO CENTRAL AND
EASTERN MONTANA TONIGHT AND WEAK SHORTWAVES IN THE SOUTHERLY FLOW
ALOFT WILL ALLOW RAIN SHOWERS TO DEVELOP OVER PARTS OF NORTHEAST
MONTANA.
THE MAIN SHORTWAVE TROUGH IN THE SOUTHERN BRANCH WILL MOVE INTO
EASTERN MONTANA FRIDAY AFTERNOON AND EVENING. SURFACE LOW WILL
MOVE NORTH ALONG STALLED COLD FRONT THAT WILL BE NEAR THE
MONTANA/DAKOTA BORDER ON FRIDAY. PRECIPITATION IS EXPECTED TO
BECOME WIDESPREAD ACROSS EASTERN MONTANA DURING THE DAY FRIDAY.
TEMPERATURES WEST OF GLASGOW AND JORDAN WILL BECOME COLD ENOUGH
DURING THE DAY ON FRIDAY FOR THE RAIN TO CHANGE TO SNOW. STRONG
NORTHWEST WINDS AREA EXPECTED OVER THE AREA AND WITH SNOW
FALLING...THERE IS A POSSIBILITY FOR BLIZZARD CONDITIONS TO
DEVELOP. UNSTABLE AIR TO THE EAST COULD BRING A FEW THUNDERSTORMS
IN THE AFTERNOON. HAVE ISSUE A BLIZZARD WATCH FROM VALLEY AND
GARFIELD COUNTIES WEST.
THE MODELS HAVE THE UPPER TROUGH BECOME A CLOSED LOW THAT BECOME
STACKED WITH THE SURFACE LOW FRIDAY NIGHT OVER THE AREA. A TROWAL
DEVELOPS OVER SOUTHERN SASKATCHEWAN AND NORTHEAST MONTANA WHICH
WILL ENHANCE THE PRECIP WHICH WILL GRADUALLY TURN TO ALL SNOW FROM
WEST TO EAST OVERNIGHT. STRONG NORTHWEST WINDS WILL KEEP BLIZZARD
TO NEAR BLIZZARD CONDITIONS OVER THE AREA INTO SATURDAY.
THE STACKED LOW LIFTS SLOWLY NORTH DURING THE DAY SATURDAY WITH
THE SNOW DIMINISHING FROM SOUTH TO NORTH DURING THE DAY. IT COULD
BE SATURDAY EVENING BEFORE THE SNOW COMPLETELY ENDS IN THE
NORTHEAST. WITH THE COLD AIR IN PLACE...TEMPERATURES WILL STRUGGLE
TO RISE HIGHER THAN THE UPPER 20S NORTH AND MID 30S SOUTH. FORRESTER
.LONG TERM...SATURDAY NIGHT THROUGH THURSDAY...
SYNOPTIC SET UP AS OF SATURDAY AFTERNOON... A COLD AIR TROUGH WILL
EXIST OVER THE NORTHERN PLAINS BARRELING EAST INTO THE GREAT
LAKES. A RIDGE LIES TO THE WEST OVER THE PACIFIC NORTHWEST WHICH
WILL PLACE NORTHEAST MONTANA IN NORTHWEST FLOW. FURTHER WEST... A
LONG WAVE COUPLET OF A TROUGH AND RIDGE EXIST OVER THE EASTERN
EXTENT OF THE NORTH PACIFIC.
SATURDAY NIGHT THROUGH TUESDAY... NORTHWEST FLOW WILL SLOWLY
TRANSITION TO A RIDGE PATTERN. THE MORE THE NORTHWEST FLOW IS
OBSERVED... THE DRYER IT BECOMES IN TH LONG RANGE. CURRENTLY
STARTING TO BITE ON THE IDEA THAT CONDITIONS WILL REMAIN MOSTLY
DRY THROUGH THE NORTHWEST FLOW PERIODS AS MODELS ARE NOT GIVING
ANY HINT OF PRECIP FOR THE LAST TWO DAYS... DESPITE THE NORMAL
CLIMO HINTING TOWARDS ODD PRECIP IN THESE KINDS OF FLOWS.
TUESDAY NIGHT ONWARD... OVERALL RIDGE BEGINS TO BREAKDOWN AND
PRECIP STARTS TO SHOW IN MODEL RUNS AS THE TROUGH FROM THE PACIFIC
IMPACTS THE REGION. TROUGH WILL START TO MOVE THROUGH THE REGION
AROUND THURSDAY AT THE END OF THE FORECAST AND SHOULD LOWER
TEMPERATURES DOWN A BIT. A BRIEF SPIKE IN POPS CAN ALSO BE
ANTICIPATED WITH THE FRONTAL PASSAGE AS WELL. GAH
&&
.AVIATION...
VFR TODAY.... ISOLATED MVFR CEILINGS COULD APPEAR AFTER MIDNIGHT
TONIGHT AS RAIN SHOWERS MOVE INTO THE REGION.
WINDS WILL SWITCH TO THE NORTHWEST THIS MORNING AS A FRONT MOVES
THROUGH. SPEEDS WILL BE AROUND 15 KTS GUSTING UP TO 25 KTS BY THE
AFTERNOON HOURS. OVERNIGHT ANTICIPATE WINDS TO VEER TO THE NORTH
AND LOSE GUSTINESS.
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...
BLIZZARD WATCH FROM FRIDAY MORNING THROUGH SATURDAY AFTERNOON
FOR CENTRAL AND SOUTHEAST PHILLIPS...CENTRAL AND SOUTHERN
VALLEY...GARFIELD...NORTHERN PHILLIPS...SOUTHWEST PHILLIPS...
NORTHERN VALLEY.
BLIZZARD WATCH FROM FRIDAY MORNING THROUGH LATE FRIDAY NIGHT FOR
PETROLEUM.
&&
$$
WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS RALEIGH NC
740 AM EDT THU APR 5 2012
.SYNOPSIS...
A COLD FRONT WILL PUSH SOUTH ACROSS THE AREA THIS MORNING...THEN
STALL OVER SC THIS AFTERNOON. LOW PRESSURE DEVELOPING ALONG THE
FRONT TONIGHT WILL MOVE OFFSHORE ON FRIDAY...WITH HIGH PRESSURE
BUILDING IN FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 AM THURSDAY...
WHILE THE MOST RECENT BATCH OF SHOWERS AND STORMS OVER THE EASTERN
CWA HAS MOVED TO THE COASTAL PLAIN...THE PRESENCE OF DISTURBED
NORTHWESTERLY FLOW ALOFT AND SCATTERED RADAR ECHOES FROM NC TO KY
WARRANTS KEEPING CHANCE POPS IN THROUGH MUCH OF THE MORNING. THE
SURFACE COLD FRONT IS CURRENTLY APPROACHING THE NC/VA BORDER FROM
THE NORTH...AND WE HAVE FOLLOWED THE HRRR WITH RESPECT TO TIMING OF
THE FROPA...WITH THE FRONT PUSHING TO NEAR THE NC/SC BORDER BY
AROUND 12Z. MODELS SHOW SHOWERS BECOMING INCREASINGLY FOCUSED
NEAR THE WEAK 850MB FRONT THAT WILL HOLD BACK OVER VA THIS
MORNING...SO AFTER 12Z WE WILL HAVE A RELATIVE MINIMUM OF SLIGHT
CHANCE POPS BETWEEN THE 850MB FRONT TO THE NORTH AND SURFACE COLD
FRONT TO THE SOUTH. WITH THE COLD FRONT SETTLING INTO SC...THE
INSTABILITY GRADIENT SHOULD SET UP JUST SOUTH OF THE NC/SC BORDER.
MOST HI-RES MODELS SUGGEST SCATTERED CONVECTION WILL DEVELOP IN THE
WARM SECTOR...BUT THERE IS VERY GOOD MODEL AGREEMENT THAT AREA NORTH
OF THE BORDER WILL BE MUCH TO STABLE TO SUPPORT THUNDERSTORMS.
LOW LEVEL COLD/DRY ADVECTION WILL STABILIZE THE BOUNDARY LAYER OVER
NC AND HELP LOCK IN STRATUS THIS MORNING..SO WE EXPECT CLOUDY
CONDITIONS ALL DAY WITH A STEADY 12KT NORTHEAST WIND. THUS TEMPS
WILL CONTINUE TO FALL THROUGH THE EARLY MORNING HOURS AND RISE VERY
LITTLE THIS AFTERNOON. MANY LOCATIONS ACROSS THE SOUTH HAVE BEEN
COOLED BY RAIN AND FORECAST TEMPS ARE ALREADY TOO WARM. A 10 TO 15
DEGREE WARM UP DIFFICULT TO ATTAIN TODAY...SO WE WILL NUDGE HIGHS
ACROSS THE SOUTH DOWN THE UPPER 60S.
&&
.SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/...
AS OF 300 AM THURSDAY...
THE UPPER LOW CURRENTLY OVER OK WILL PUSH EAST ACROSS THE MID MS
VALLEY REGION TODAY...THEN DIP SOUTHEAST ACROSS AL/GA TONIGHT AS IT
BECOMES ABSORBED INTO THE CYCLONIC UPPER FLOW OVER THE NEW ENGLAND
AND THE MID ATLANTIC STATES. 60-80M HEIGHT FALLS AND INCREASINGLY
DIFFLUENT FLOW ALOFT AHEAD OF THE UPPER LOW WILL LEAD TO
CYCLOGENESIS ALONG THE COLD FRONT NEAR THE SC/GA BORDER LATE THIS
EVENING AND OVERNIGHT. THE GFS IS A NORTHERN OUTLIER WITH ITS
PRESSURE FALLS AND EVENTUALLY TRACK OF THE SURFACE LOW. WE WILL
FAVOR THE ECMWF AND NAM FOR THEIR CONSISTENCY WITH THE TRACK OF THE
LOW. MOST OF THE RAIN WITH THE SYSTEM WILL BE FOCUSED ALONG THE
FRONT AND SURFACE LOW...BUT A SHORTWAVE DROPPING SOUTH OUT OF
EASTERN CANADA INTO THE MID-ATLANTIC STATES SHOULD HELP DRAW
MOISTURE NORTH INTO THE VICINITY OF THE 925-850MB FRONT WHICH IS
FORECAST TO LIE ACROSS THE CAROLINAS OVERNIGHT. THUS WHILE RAIN MAY
INITIALLY BE SLOW TO PROGRESS ACROSS THE SOUTHERN PIEDMONT AFTER
21-00Z THIS EVENING...THE RAIN SHIELD IS EXPECTED TO EXPAND
NORTHWARD ACROSS MOST OF THE CENTRAL NC. A MODEL CONSENSUS OF
QPF...WITH GENERALLY GOOD AGREEMENT AMONG MODELS...GIVES 0.25-0.5"
FOR AREAS SOUTH OF HWY 64. IT IS POSSIBLE THAT AREA NEAR THE VA
BORDER COULD SEE LITTLE TO NO RAIN IF THE SURFACE LOW TRACKS FURTHER
SOUTH WHERE MOST MODELS SHOW IT TRACKING. LOWS WILL FALL INTO THE
UPPER 40S...WITH A CHILLY 10-15KT NORTHEAST WIND ON THE NORTHWESTERN
SIDE OF THE SURFACE LOW.
ONCE THE SURFACE LOW MOVES OFFSHORE FRIDAY MORNING...WINDS WILL
SLOWLY BACK AROUND TO NORTHERLY DURING THE DAY ON FRIDAY...HELPING
TO FILTER DIRER AIR IN FROM THE NORTH. MODELS CONTINUE TO TREND
TOWARD ALL OF THE CWA CLEARING BY FRIDAY EVENING. BECAUSE
CLOUDS...AND PRECIP EARLY...WILL LINGER LONGEST ON THE
SOUTHEAST...TEMPS SHOULD BE FAIRLY UNIFORM ACROSS THE AREA...IF NOT
WARMER ACROSS THE NORTH. WE WILL CONTINUE THE FORECAST OF HIGHS IN
THE LOWER 60S. HIGH PRESSURE WILL BUILD IN FROM THE GREAT LAKES
FRIDAY NIGHT...LEADING TO A MUCH DRIER AIRMASS OVER CENTRAL NC AND
POTENTIAL FOR LOWS TO REACH THE UPPER 30S. A LIGHT WIND SHOULD KEEP
TEMPS FROM REACHING THEIR FULL RADIATIONAL COLLING POTENTIAL...BUT A
LIGHT FROST COULD BE POSSIBLE IN COOLER SHELTERED AREAS.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 300 AM THURSDAY...
THE LONG TERM PERIOD WILL START OFF WITH HIGH PRESSURE BUILDING
SOUTHEASTWARD ACROSS THE CAROLINAS ON SATURDAY IN THE WAKE OF A
SHORT WAVE MOVING OFF THE EAST COAST. WORTH NOTING THE CANADIAN
ORIGIN OF THIS HIGH AND ASSOCIATED COOL AIRMASS FOR THIS TIME OF
THE YEAR...HOWEVER COLDEST AIR WILL SLIDE BY TO OUR EAST AS THE
TROUGH BOTTOMS OUT OVER THE WESTERN ATLANTIC. NONETHELESS...LATEST
GUIDANCE IS IN LINE WITH ONGOING TEMP FORECAST WHICH SUGGESTS LOWS
SATURDAY MORNING IN THE MID 30S...COLDEST NORTH OF HWY 64. CAN`T
RULE OUT THE POSSIBILITY OF SOME FROST AROUND SUNRISE SATURDAY
MORNING IN THE COLDER/SHELTERED SPOTS...BUT GUIDANCE DOES SHOW THE
PRES GRADIENT AND SOME SFC WIND PERSISTING THROUGH SUNRISE...SO THAT
COULD HELP TO PRECLUDE WIDESPREAD COLDER TEMPS AND FROST. THEN THE
REMAINDER OF THE DAY WILL BE SUNNY WITH A DRY AIRMASS IN PLACE AND
HIGHS ABOUT 5 DEGREES BELOW NORMAL.
THE HIGH WILL MOVE SOUTH OF THE CAROLINAS SATURDAY NIGHT AS THE NEXT
SHORT WAVE MOVES FROM THE NORTHERN PLAINS TO THE GREAT LAKES. WITH A
CHILLY AND DRY AIRMASS STILL IN PLACE OVER OUR AREA AND LIGHT TO
CALM WINDS OVERNIGHT...LOWS SUNDAY MORNING WILL BE COLD ONCE AGAIN.
RIGHT NOW GUIDANCE SUGGESTS TEMPS WILL BE SEVERAL DEGREES WARMER
THAN SATURDAY MORNING...BUT ALSO EXPECT LESS WIND SUNDAY MORNING
COMPARED TO SATURDAY...THUS TEMPS MAY BE CLOSE TO VALUES NEEDED FOR
PATCHY FROST. IT WILL DEFINITELY BE WORTH CHECKING BACK FOR UPDATES
WITH LATER FORECASTS.
ON SUNDAY...THE AFOREMENTIONED SHORT WAVE WILL DIVE SE ACROSS
THE GREAT LAKES AND ITS ATTENDANT SFC COLD FRONT WILL MOVE FROM THE
TN VALLEY IN THE MORNING TO OUR WESTERN PIEDMONT BY EVENING. WITH A
DRY AIRMASS IN PLACE AND MODEST MOISTURE TRANSPORT INTO THE FRONTAL
SYSTEM FROM THE SOUTH (THANKS TO HIGH PRESSURE OVER THE DEEP SOUTH
AND WNW MIDLEVEL FLOW GENERALLY EAST OF THE MISSISSIPPI)...I`M A
LITTLE LEARY OF THE PRECIP THAT THE GFS IS GENERATING OVER OUR AREA
LATE SUNDAY AND PREFER THE DRIER ECMWF SOLUTION. FOR NOW WILL KEEP
POPS AOB 10 PERCENT FOR THIS TIME...BUT IF GUIDANCE CONTINUES TO
TREND WETTER...MAY NEED TO INCREASE POPS FOR THIS TIME WITH FUTURE
FORECAST CYCLES.
THEREAFTER...THE PATTERN WILL CONTINUE TO AMPLIFY AND TREND COOLER
OVER THE EASTERN PORTION OF NORTH AMERICA AS A SERIES OF SHORT WAVE
TROUGHS DEEPEN THE LONG WAVE PATTERN ...PARTICULARLY OVER THE
NORTHEAST STATES AND EXTENDING SOUTH ACROSS OUR AREA. WHAT THIS
MEANS FOR US IS A CONTINUATION OF THE COOL TREND FOR THE EARLY TO
MIDDLE PART OF THE WEEK...WITH MORNING FROST/FREEZE POTENTIAL...
PARTICULARLY DURING THE MIDDLE PART OF THE WEEK. THE EXACT TIMING
AND DETAILS WILL BE ASSOCIATED WITH THE TIMING AND STRENGTH OF
INDIVIDUAL SHORT WAVES ROTATING AROUND THE LONG WAVE TROUGH...BUT
RIGHT NOW LOOKS LIKE ONE POTENT SHORT WAVE WILL MOVE ACROSS THE AREA
LATE MONDAY OR EARLY TUESDAY MORNING WITH INCREASED POPS ALONG/AHEAD
OF IT...AND THEN ANOTHER SHORT WAVE PASSAGE ON WEDNESDAY. SURGES OF
COOLER AIR WILL FOLLOW EACH OF THESE WAVES.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 740 AM THURSDAY...
A COLD FRONT IS SURGING SOUTH THROUGH CENTRAL NC THIS MORNING...WITH
WINDS TURNING TO NORTHEASTERLY AND EXPECTED TO INCREASE TO AROUND
12KT BY MID MORNING. SOME LIGHT RAIN IS PUSHING ACROSS THE TRIAD
AND INTO THE NORTHERN PIEDMONT...CAUSING BRIEF MVFR VSBYS..
HOWEVER...CEILINGS SHOULD REMAIN ABOVE 3K FT. THESE SHOWERS WILL
CONTINUE TO MOVE EAST-NORTHEAST AND IF THEY HOLD TOGETHER THEY
SHOULD IMPACT KRDU/KRWI BY 14-15Z. MEANWHILE STRATUS WILL DEVELOP
OVER THE AREA AS MOISTURE INCREASES AHEAD OF A LOW PRESSURE SYSTEM
APPROACHING FROM THE WEST. THE BEST CHANCE OF MVFR CEILINGS DURING
THE DAY TODAY WILL BE AT KFAY WHERE BETTER LOW LEVEL MOISTURE WILL
RESIDE NEAR THE STALLING COLD FRONT. ALL OTHER SITES ARE FORECAST
TO REMAIN AT VFR LEVELS.
TONIGHT..RAIN WILL OVERSPREAD THE AREA FROM SOUTHWEST...MOSTLY AFTER
00Z....EXPANDING NORTHWARD AND INCREASING IN INTENSITY AFTER
06Z....AS THE LOW PRESSURE SYSTEM MOVES ACROSS GA AND SC. THERE IS
GENERALLY GOOD AGREEMENT THAT CEILINGS WILL REMAIN IN THE 2-4K FT
RANGE AT MOST LOCATIONS....THOUGH SOME IFR CEILINGS WILL BE POSSIBLE
ACROSS THE SOUTHERN PIEDMONT. IF THE RAIN IS HEAVIER THAN MODELS
PROJECT...THEN LOWER CEILINGS...POSSIBLY IFR...COULD OCCUR AFTER
MIDNIGHT AS FAR NORTH AS KGSO/KINT/KRWI.
AS THE SURFACE LOW THAT IS FORECAST TO DEVELOP ALONG THE SC COAST
MOVES FURTHER OFFSHORE...RAIN WILL COME TO AN END FRIDAY MORNING.
DRIER AIR AD HIGH PRESSURE WILL BUILD FRIDAY AND FRIDAY NIGHT...WITH
VFR CONDITIONS EXPECTED FROM FRIDAY AFTERNOON INTO EARLY NEXT WEEK.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...SMITH
NEAR TERM...SMITH
SHORT TERM...SMITH
LONG TERM...NMP
AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS SACRAMENTO CA
912 AM PDT THU APR 5 2012
.SHORT TERM DISCUSSION...
A COLD UPPER LEVEL TROUGH IS LOCATED OVER THE REGION BRINGING A
COOL START TODAY. SOME LOCATIONS REACHED CLOSE TO RECORD LOWS THIS
MORNING. RED BLUFF DROPPED TO 34 DEGREES...ONE DEGREE SHY OF THE
RECORD LOW OF 33. SACRAMENTO EXECUTIVE AIRPORT WAS 36...WITH THE
RECORD AT 35. SOME OTHER COOL SPOTS INCLUDE LINCOLN AT 31...CHICO
AT 30. UP IN THE SIERRA...STANISLAUS MEADOW NEAR TAMARACK AT 7750
FEET ELEVATION DROPPED TO 1 DEGREE THIS MORNING. UP IN THE
BURNEY/FALL RIVER MILLS AREA...SPOTTERS REPORTED 2-3 INCHES OF
SNOW THAT FELL WITH SHOWERS THAT MOVED THROUGH OVERNIGHT.
A SHORTWAVE JUST OFF THE COAST WILL ROUND THE BASE OF THE TROUGH
BRINGING THE POTENTIAL FOR SHOWERS IN THE MOUNTAINS. RADAR SHOWS
SOME LIGHT RETURNS OFF THE COAST AND EXPECT THESE TO MOVE INLAND
THROUGH THE DAY. A FEW WEAK RETURNS ARE ALSO LINGERING OVER THE
SIERRA CREST BUT LITTLE OR NOTHING SHOULD BE FALLING OUT OF IT. COULD
SEE SOME AFTERNOON CONVECTION AS COLD CORE (-34 C AT 500B) PASSES
OVER THE CWA. MOISTURE IS THE LIMITING FACTOR WITH PW OF .24
INCHES AT OAKLAND 54 PERCENT OF NORMAL AND .12 AT RENO WHICH IS 48
PERCENT OF NORMAL. OROGRAPHIC LIFT COUPLED WITH THE INSTABILITY
SHOULD BE ENOUGH TO DEVELOP SOME SHOWERS OVER THE MOUNTAINS. THE
WRF AND HRRR MODELS REFLECT THIS WITH THE BULK OF THE ACTIVITY
OVER THE MOUNTAINS OF WESTERN PLUMAS/LASSEN PARK AND THE NORTHERN
SIERRA. ISOLATED THUNDERSTORMS COULD DEVELOP IN THOSE AREAS THIS
AFTERNOON. FORECAST LOOKS ON TRACK...NO UPDATE NEEDED. EK
.EXTENDED DISCUSSION (MONDAY THROUGH THURSDAY)
A BROAD LONGWAVE TROUGH PARKS ITSELF OUT OVER THE ERN PAC NEAR
135W THROUGH MUCH OF THE EXTENDED, BEFORE COMING ABOARD LAND LATE
TUESDAY. THE MODELS BROAD BRUSH NRN CAL IN A CYCLONIC
SOUTHWESTERLY PATTERN WITH WAVES TRYING TO SPREAD THEIR PRECIP
PROPAGANDA INTO NORTHWEST CAL. THE TIMING OF ANY PERTURBATIONS WITH
INCREASED CHANCES OF PRECIP AT THIS POINT ARE DIFFICULT, SO WE
KEPT MENTION OF PRECIP OVER THE COASTAL RANGE, SHASTA COUNTY, AND
INTO ADJACENT NRN SAC VALLEY. THE LONGWAVE AXIS FINALLY MOVES
OVER CA AND SPREADS PRECIP CHANCES FARTHER SOUTH LATE TUESDAY INTO
WEDNESDAY. SPLIT FLOW ON THURSDAY MAY KEEP A THREAT OF SOME LIGHT
PRECIP, BUT MINIMAL. WARM AIR ADVECTION WILL KEEP SNOW LEVELS
6000-7000 FT AND HIGHER INTO TUESDAY, THEN LOWER TO 5000-6000 FT
THURSDAY. JCLAPP
&&
.AVIATION...
COLD CYCLONIC FLOW OVER NORCAL AS UPPER TROF OVER THE WRN CONUS
DEEPENS TODAY AS STRONG UPPER AIR DISTURBANCE MOVES SEWD ACROSS
THE S SFO BAY AREA AND INTO THE SAN JOAQUIN VALLEY. AIR MASS
THOUGH IS VERY DRY WITH PW ONLY ABOUT 50% OF NORMAL. VFR
CONDITIONS IN THE VALLEY WITH FEW-SCT CUMULUS DEVELOPING DURING
AFTERNOON HRS...AND NWLY FLOW 10-17 KTS OVER MOST OF THE VALLEY.
LOCAL MVFR CIGS/VSBYS OVER MTNS WITH SCATTERED SHOWERS AND
POSSIBLE ISOLD -TSRAGS DURING AFTERNOON...AIDED BY ENHANCED LIFT
FROM TOPOGRAPHY. FREEZING LEVEL ON KOAK RAOB 4300 FT THIS
MORNING...WITH LITTLE INCREASE EXPECTED TODAY.
&&
.STO WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
339 PM EDT THU APR 5 2012
.SYNOPSIS...
A LARGE AREA OF HIGH PRESSURE WILL CONTINUE TO BUILD SOUTHWARD FROM
CANADA ACROSS MUCH OF THE EASTERN PORTION OF THE COUNTRY TONIGHT
THROUGH THE EARLY PART OF THE WEEKEND. A SERIES OF FRONTAL
BOUNDARIES ARE EXPECTED TO AFFECT THE AREA LATE IN THE WEEKEND INTO
EARLY AND MID PART OF NEXT WEEK AS AS AN AREA OF LOW PRESSURE WILL
SPIN AND REMAIN NEARLY STATIONARY ACROSS NEW ENGLAND.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
THE GFS INITIALIZATION LOOKED BETTER AT 500MB, BUT THE WRF-NMMB WAS
BETTER AT 925MB WITH A MODEL TIE AT 850MB. SO WE WILL USE THE GFS
FOR THE UPPER AIR FEATURES AND THE WRF-NNMB FOR THE THERMAL PROFILES.
WE ARE GOING TO EXPAND THE FREEZE WARNING INTO SECTIONS OF THE PHL
METRO AREA BASED ON THE CONTINUATION AND PRETTY GOOD CORROBORATION
OF THE STAT GUIDANCE. THE GREATEST CONFIDENT AREA IS THE LEHIGH
VALLEY, BERKS COUNTY AND NORTHERN NJ WHERE THE INITIAL WARNING WAS
ISSUED THIS MORNING.
TONIGHT BEARS SOME SIMILARITY TO LAST NIGHT AS ANOTHER SHOT OF
COLDER AIR IS FORECAST TO ARRIVE BEHIND A DEPARTING SHORT WAVE TROF.
THIS TROF AND THE H250 JET PRECEDING IT WILL ASSIST GETTING SOME OF
THE CIRRUS IN THE VIRGINIAS AND MARYLAND INTO THE SOUTHERN PART OF
OUR CWA DURING THE EVENING. BEHIND THE DEPARTING TROF, THERE MAY
VERY WELL BE AN INCREASE IN THE WINDS TOWARD MORNING AS THE CAA SHOT
MOVES THROUGH. REGARDLESS THIS IS MORE OF AN ADVECTION AND NOT
RADIATIONAL TYPE FREEZE. ITS EITHER FREEZE OR NOT WITH NOT MUCH
FROST EXPECTED. THE INCIPIENT AIR MASS IS COLDER THAN NORMAL FOR
THIS TIME OF YEAR, NOT OFTEN WE HAVE BEEN ABLE TO TYPE THAT IN 2012.
STAT GUIDANCE IS PRETTY CLOSE. WHERE THEY WERE NOT, BASED ON THIS
MORNING`S MINS, WE LEANED TWD THE COLDER NAM MOS.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
VERY DRY AIR MASS REMAINS IN PLACE OVER OUR CWA ON FRIDAY. SO IN
SPITE OF A SHARPENING 500MB TROF ALOFT, WE MAY NOT BE ABLE TO
GENERATE MANY CLOUDS AT ALL. THE GRADIENT BETWEEN THE LOW PRESSURE
SYSTEM DEPARTING OFF THE SOUTHEAST COAST AND A HIGH PRESSURE SYSTEM
OVER THE GREAT LAKES SHOULD BE GREATER THAN TODAY. WE ARE
FORECASTING A BREEZIER DAY WITH FIRE WEATHER CONCERNS. FORECAST
850MB AND 925MB TEMPERATURES ARE SUGGESTING TAKING A DEGREE OR TWO
OFF OF TODAY`S MAX TEMPS, THUS A STAT GUIDANCE COMPROMISE FOR MOST
LOCATIONS.
&&
.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
FAIR, DRY WEATHER IS STILL EXPECTED FOR THE EARLY PART OF THE LONG
TERM FORECAST. HIGH PRESSURE WILL CONTINUE TO BUILD SOUTH OUT OF
CANADA ACROSS MUCH OF THE EASTERN PORTION OF THE COUNTRY THROUGH
THE EARLY PART OF THE WEEKEND. A TROUGH ALOFT SHOULD KEEP THE
THICKNESSES FROM RISING SHARPLY SATURDAY, WHICH WILL KEEP THE MAX
TEMPERATURES WITHIN A FEW DEGREES ABOVE NORMAL. BY SUNDAY, SLIGHT
RIDGING ALOFT WILL TAKE PLACE, HELPING THICKNESSES RISE AND
BRINGING MAX TEMPERATURES A FEW MORE DEGREES ABOVE NORMAL. LOWS
FOR FRIDAY NIGHT THROUGH SATURDAY NIGHT SHOULD BE CLOSE TO NORMAL
AS GOOD RADIATIONAL COOLING SHOULD TAKE PLACE. WOULD NOT BE
SURPRISED TO SEE MORE FROST/FREEZE STATEMENTS THIS WEEKEND.
THE LARGE AREA OF HIGH PRESSURE WILL GET SQUEEZED OUT OF THE AREA ON
SUNDAY INTO NEXT WEEK AS AN AREA OF LOW PRESSURE RETROGRADES BACK
TOWARD NEW ENGLAND AND ABSORBS ANOTHER LOW MOVING THROUGH SOUTHERN
CANADA. THE SURFACE LOW AND MID/UPPER TROUGH ARE FORECAST TO LINGER
ACROSS NEW ENGLAND AND THE EAST COAST FOR MUCH OF THE EARLY PORTION
OF NEXT WEEK. WITH THE PRESENCE OF THESE FEATURES, RAIN CHANCES
RETURN BACK INTO THE FORECAST, ALBEIT SMALL CHANCES. HOPEFULLY WE
CAN GET SOME MEASURABLE RAINFALL AFTER BEING SO DRY LATELY, NEARLY 25
TO 50 PERCENT BELOW NORMAL IN FACT FOR THE LAST 30 DAYS OR SO.
WITH THE TROUGH ALOFT ACROSS THE EAST, TEMPERATURES FOR THE EARLY
TO MIDDLE OF NEXT WEEK SHOULD BEGIN SLIGHTLY ABOVE NORMAL, THEN
FALL A FEW DEGREES BELOW.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD. A MODERATE NORTH TO
NORTH-NORTHWEST WIND IS EXPECTED TO DIMINISH TOWARD EVENING BUT THEN
PICK UP AGAIN DURING THE OVERNIGHT. WINDS BECOME GUSTY BY FRIDAY
AFTERNOON, WITH GUSTS MAINLY BETWEEN 20 TO 25 KNOTS.
LATEST HRRR AND HI RES NMMB SUPPORT THOUGHTS ABOUT A SEA BREEZE
STRUGGLING TO GET MUCH INLAND, ALTHOUGH IT DID REACH KACY THIS
AFTERNOON.
OUTLOOK...
VFR CONDITIONS ARE EXPECTED THROUGH THE WEEKEND INTO EARLY NEXT
WEEK. THERE IS A CHANCE FOR SOME RAIN FOR THE EARLY TO MIDDLE OF
NEXT WEEK, BUT IT IS TOO FAR OUT TO DETERMINE IF BELOW VFR
CONDITIONS WILL OCCUR.
WINDS EACH AFTERNOON SHOULD GET GUSTY WITH GUSTS 20-25 KNOTS
SATURDAY AND 15-20 KNOTS SUNDAY. MONDAY AND TUESDAY OF NEXT WEEK
COULD GUST EVEN HIGHER AS THE PRESSURE GRADIENT TIGHTENS WITH LOW
PRESSURE LOCATED TO OUR NORTH.
&&
.MARINE...
A SEA BREEZE FRONT IS GOING TO PRODUCE A LOW CONFIDENCE WIND
DIRECTION FORECAST THIS EVENING. AN APPROACHING TROF WILL ALSO KEEP
WINDS A BIT ON THE VARIABLE SIDE. THANKFULLY OVERALL SPEEDS SHOULD
BE LIGHT. ONCE THE TROF CLEARS, A PREVAILING NORTH WIND WILL
RE-ESTABLISH ITSELF.
WE ARE GOING TO ISSUE A SMALL CRAFT ADVISORY FOR OUR SOUTHERN
ATLANTIC WATERS FOR LATE TONIGHT INTO FRIDAY MORNING AS THE NEXT
SURGE OF COLD AIR ADVECTION WINDS IS EXPECTED TO BE STRONGEST IN
THESE AREAS. ONCE AGAIN THERE COULD ALSO BE A SWELL RELATED
COMPONENT TO THE ADVISORY. FARTHER NORTH AND IN DELAWARE BAY, THE
FORECAST WINDS ARE NOT EXPECTED TO BE AS STRONG OR OCCUR BEFORE
THERE IS A GREATER AIR AND WATER TEMPERATURE DIFFERENTIAL.
ONCE THIS SURGE DEPARTS WINDS, LIKE THURSDAY AFTERNOON, SHOULD ONCE
AGAIN DROP OR REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA. BUT, WE
ARE NOT EXPECTING A SEA BREEZE OR CHANGE IN WIND DIRECTION TO
OCCUR.
OUTLOOK...
WINDS COULD APPROACH SMALL CRAFT ADVISORY LEVELS FRIDAY NIGHT INTO
SATURDAY AS AN AREA OF LOW PRESSURE PASSES TO OUR EAST AND THE
PRESSURE GRADIENT TIGHTENS ACROSS THE AREA. WINDS ARE EXPECTED TO
FALL BELOW ADVISORY LEVELS ON SUNDAY, THEN INCREASE AGAIN MONDAY
INTO TUESDAY AS THE PRESSURE GRADIENT TIGHTENS WITH LOW PRESSURE
LOCATED TO OUR NORTH.
&&
.FIRE WEATHER...
WE ARE GOING TO ISSUE A FIRE WEATHER WATCH FOR FRIDAY FOR
PENNSYLVANIA AND NEW JERSEY. WE ARE GOING TO HOLD OFF ON MARYLAND
AND DELAWARE AS THE NEEDED WIND SPEED CRITERIA IS HIGHER AND THE
OVERALL FORECAST WINDS ARE EXPECTED TO BE A LITTLE LIGHTER IN
DELMARVA.
THIS MAY NOT BE THE LAST DAY OF CONCERN AS A LOW DEPARTING OFF THE
SOUTHEAST COAST WILL INCREASE THE GRADIENT FURTHER ON SATURDAY WITH
NO EXPECTED INCREASE IN DEW POINT OR HUMIDITY LEVELS. SO A WATCH
MAY BE NEEDED AGAIN FOR SATURDAY AS WELL. THE OVERALL GRADIENT
SHOULD BE LESS ON SUNDAY.
&&
.TIDES/COASTAL FLOODING...
WE ARE NOT GOING TO ISSUE ANY HEADLINES OR STATEMENTS WITH THIS
EVENING`S HIGH TIDE. THE TIDAL DEPARTURES CONTINUE TO EASE AS THE
WINDS HAVE BECOME LIGHTER WITHOUT A LONG NORTHEASTERLY SPIRAL.
IF WE ARE WRONG, IT WOULD BE IN CAPE MAY COUNTY NJ AND SUSSEX COUNTY
DE WHERE MAINTAINING CURRENT DEPARTURES WOULD JUST GET THEM TO MINOR
TIDAL FLOODING LEVELS. WE WILL CONTINUE A MENTION IN THE HWO
IN THE INTEREST OF CAUTION.
AFTER THAT, THE COMBINATION OF THE APPROACHING SPRING TIDES WITH THE
FULL MOON AND THE EKMAN SPIRAL EFFECT FROM THE LIKELY AND
PREDOMINATELY NORTHERLY WINDS NEAR THE COAST MAY CAUSE MINOR TIDAL
FLOODING WITH THE EVENING AND OVERNIGHT HIGH TIDE CYCLES FROM FRIDAY
EVENING THROUGH THE WEEKEND. BY SATURDAY, WE WILL ONLY NEED
DEPARTURES OF ABOUT HALF A FOOT ABOVE NORMAL TO REACH THE CRITERIA.
IN UPPER DELAWARE BAY, THE TIDAL DELAWARE RIVER AND CHESAPEAKE BAY,
THE NORTHERLY FLOW COUPLED WITH NORMAL OR BELOW NORMAL FRESHWATER
RUNOFF SHOULD MITIGATE ANY TIDAL RELATED PROBLEMS.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...FREEZE WARNING FROM 3 AM TO 8 AM EDT FRIDAY FOR PAZ060>062-
067>069.
FIRE WEATHER WATCH FROM FRIDAY MORNING THROUGH FRIDAY EVENING
FOR PAZ054-055-060>062-067>071.
NJ...FREEZE WARNING FROM 3 AM TO 8 AM EDT FRIDAY FOR NJZ007>010-015-
020>022-027.
FIRE WEATHER WATCH FROM FRIDAY MORNING THROUGH FRIDAY EVENING
FOR NJZ001-007>010-012>027.
DE...NONE.
MD...FREEZE WARNING FROM 3 AM TO 8 AM EDT FRIDAY FOR MDZ008.
MARINE...SMALL CRAFT ADVISORY FROM 4 AM TO NOON EDT FRIDAY FOR
ANZ452>455.
&&
$$
SYNOPSIS...ROBERTSON
NEAR TERM...GIGI
SHORT TERM...GIGI
LONG TERM...ROBERTSON
AVIATION...KLINE/GIGI/ROBERTSON
MARINE...GIGI/ROBERTSON
FIRE WEATHER...GIGI
TIDES/COASTAL FLOODING...GIGI
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
153 PM EDT THU APR 5 2012
.SYNOPSIS...
A LARGE AREA OF HIGH PRESSURE WILL BUILD SOUTHWARD FROM CANADA
TODAY THROUGH THE WEEKEND. A SERIES OF FRONTAL BOUNDARIES ARE
EXPECTED TO AFFECT THE AREA LATE IN THE WEEKEND INTO THE MIDDLE OF
NEXT WEEK AS LOW PRESSURE MOVING THROUGH THE GREAT LAKES MERGES
WITH AN AREA OF LOW PRESSURE IN THE CANADIAN MARITIMES AND CARVES
OUT A TROUGH OVER THE EASTERN HALF OF THE NATION. SOME UNSETTLED
WEATHER IS POSSIBLE DURING THIS TIME.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
CURRENT FORECAST PRETTY MUCH STAYING ON COURSE. WE DID NUDGE MAX
TEMPS UP SLIGHTLY AS THE TREND HAS HELD THROUGH THE MORNING. IT
LOOKS LIKE THE CAA STRATOCU CLOUDS UP NORTH ARE RUNNING OUT OF
AVAILABLE MOISTURE. PLUS THERE IS ANOTHER LULL IN THE PRESSURE
PATTERN FORMING OVER OUR CWA. THE ENTRANCE REGION OF THE 250MB JET
IS OVER OUR CWA, SO SOME OF THE MID AND HIGH LEVEL CLOUDS SOUTH
WILL MAKE SOME MOVEMENT INTO OUR CWA THIS AFTERNOON. WE DID UP THE
SKY COVER SOUTH.
TODAY GENERALLY SHOULD BE A BENIGN WEATHER DAY WITH TEMPERATURES
A BIT MORE THAN 10 TO 15 DEGREES COOLER THAN WEDNESDAY THANKS TO
THE COLD FRONT THAT DROPPED THROUGH OUR AREA DURING THE NIGHT.
PERHAPS SOME HIGH CLOUDS WILL BE AROUND (LIKELY MORE SOUTH THAN
NORTH), WINDS STARTED MODERATE FROM THE NORTH, BUT AS A RATHER
WEAK AND DRY TROUGH APPROACHES THE AREA THIS AFTERNOON THEY ARE
EXPECTED TO DIMINISH A BIT. THE H925 FLOW IS IN OPPOSITION TO A
SEA BREEZE LATER TODAY, BUT IT IS ON THE LIGHT SIDE. WE HAVE A SEA
BREEZE DEVELOPING AND EXPECT IT TO REACH A FEW MILES INLAND,
INCLUDING TO AROUND THE ATLANTIC CITY AREA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/...
WE ISSUED A FREEZE WARNING FOR THE COUNTIES WE ARE MOST CONFIDENT
WILL REACH FREEZING TEMPERATURES. THERE MAY BE AN EXPANSION LATER
TODAY IN PARTS OF DELMARVA AND THE LOCAL PHL METRO AREA.
SKIES ARE EXPECTED TO BE MAINLY CLEAR TONIGHT. AGAIN, HIGH CLOUDS
WILL BE MORE APPARENT NORTH THAN SOUTH. WINDS ARE EXPECTED TO
LIGHTEN IN A CLIMATOLOGICALLY NORMAL WAY AT FIRST, BUT THE PASSAGE
OF THE TROUGH TONIGHT MAY CAUSE THEM TO PICK UP A LITTLE OVERNIGHT
DESPITE SOME PARTIAL DECOUPLING. WE THEREFORE HAVE BEEN CAREFUL
ABOUT DROPPING THE BOTTOM OUT FROM TEMPERATURES. WE WILL MAINTAIN
THE POSSIBILITY OF FROST OR FREEZING TEMPERATURES OVER MANY
LOCATIONS IN THE HWO. OUR FORECAST MINS ARE A BLEND OF CONTINUITY
AND STAT GUIDANCE.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
A LARGE AREA OF HIGH PRESSURE BUILDING DOWN FROM CANADA WILL BE
THE DOMINANT WX FEATURE FOR THE START OF THE EXTENDD PD. HOWEVER,
IT WILL BE REPLACED BY LOW PRESSURE AND AN H5 TROF FOR THE LATER
PORTION OF THE PD. ON FRIDAY, THE HIGH WILL BEGIN BUILDING IN AS
LOW PRESSURE MOVES OFF THE SERN CONUS COAST. THIS LOW WILL MOVE
WELL OFF THE ATLC COAST BEFORE RETROGRADING WWD TWD THE CANADIAN
MARITIMES EARLY NEXT WEEK. IT SHOULD BE NOTED THAT THE LATEST MDL
RUNS ARE NOW MUCH WEAKER AND FURTHER OFF THE COAST WITH THIS SYS
THAN PREV RUNS, ESPECIALLY THE GFS, AS IT MOVES NWD THEN NWWD.
WITH THE HIGH CONTROLLING THE WX THRU SUNDAY, EXPECT DRY CONDS
WITH SEASONAL TO SLIGHTLY ABV NRML TEMPS. THERE IS VERY HIGH
CONFIDENCE IN THIS PORTION OF THE FCST.
THEN THE MDLS BEGIN TO DIVERGE AND CONFIDENCE DROPS EARLY NEXT
WEEK. THE AFOREMENTIONED LOW PRESSURE SYSTEM MOVES TWD THE
CANADIAN MARITIMES AND THIS FEATURE COUPLED WITH ANOTHER LOW
DROPPING SEWD ACRS THE PLAINS WILL HELP CARVE OUT A LARGE TROF
OVER THE ERN CONUS. SEVERAL WAVES AND WEAK FRONTS WILL ROTATE THRU
THIS TROF THRU MIDWEEK AND BRING SHOTS OF PRECIP TO THE REGION.
HOWEVER, THE GFS,AS USUAL,IS WETTER THAN THE REST OF THE MDL
GUIDANCE, AND AT THIS MDL DISTANCE IT IS DIFFICULT TO PINPOINT
EXACTLY WHEN THE WETTEST PD WILL BE, BUT RIGHT NOW IT LOOKS TO BE
AT SOME POINT TUESDAY OR WEDNESDAY. ALSO, WHILE THE MDLS SEEM TO
HAVE SOME DECENT AGREEMENT ON THE GENERAL FEATURES, THEY DISAGREE
ON JUST HOW THEY INTERACT. SO, FOR NOW, WILL JUST KEEP SCHC AND
LOW CHC POPS.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD. A MODERATE NORTH
TO NORTH-NORTHWEST WIND IS EXPECTED TO DIMINISH TOWARD EVENING BUT THEN
PICK UP AGAIN DURING THE OVERNIGHT. WINDS BECOME GUSTY BY FRIDAY
AFTERNOON, WITH GUSTS MAINLY BETWEEN 20 TO 25 KNOTS.
LATEST HRRR AND HI RES NMMB SUPPORT THOUGHTS ABOUT A SEA BREEZE
STRUGGLING TO GET MUCH INLAND, ALTHOUGH WE DO EXPECT IT TO REACH
KACY LATE TODAY.
OUTLOOK...
VFR CONDITIONS ARE THRU THE WEEKEND WITH A LARGE AREA OF HIGH
PRESSURE BUILDING DOWN FROM CANADA. WINDS COULD BECOME GUSTY EACH
AFTERNOON THROUGH THE WEEKEND, WITH GUSTS GENERALLY AROUND 15-20
KNOTS.
&&
.MARINE...
WINDS AND SEAS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA
THIS AFTERNOON. WINDS AND SEAS WILL PICK UP SOME TONIGHT WITH THE
PASSAGE OF A WEAK TROUGH, BUT THE PUSH BEHIND THE TROUGH DOESN`T
LOOK AS SUBSTANTIAL AS THE ONE THAT WAS BEHIND THE FRONT THAT CAME
THROUGH DURING THE NIGHT.
OUTLOOK...
HIGH PRESSURE WILL BUILD TO THE WEST OF THE WATERS FRIDAY THROUGH THE
WEEKEND. THE PRESSURE GRADIENT ACROSS THE WATERS SHOULD KEEP A
STEADY NORTH TO NORTHWEST WIND ACROSS THE AREA. IT IS POSSIBLE
THAT WIND GUSTS COULD APPROACH SMALL CRAFT ADVISORY DURING THIS
PERIOD, ESPECIALLY SATURDAY INTO SUNDAY.
&&
.FIRE WEATHER...
WE STILL THINK WINDS WILL FALL SHORT OF THE RED FLAG WARNING
CRITERIA AROUND OUR FORECAST AREA, SO WE WILL ISSUE A SPECIAL
WEATHER STATEMENT TO HIGHLIGHT THE DRY FINE FUELS AND THE LOW
RELATIVE HUMIDITY LEVELS THIS AFTERNOON.
A LOW DEPARTING OFF THE SOUTHEAST COAST MIGHT INCREASE THE GRADIENT
WITH A GREATER CHANCE FOR RED FLAG WARNING CONDITIONS ON FRIDAY AND
ESPECIALLY SATURDAY.
&&
.TIDES/COASTAL FLOODING...
LATE THIS MORNING, DEPARTURES (WERE THEY TO REMAIN CONSTANT)
SUPPORTED THE POSSIBILITY OF JUST REACHING MINOR TIDAL FLOODING
ALONG THE SOUTH COAST AND LOWER DELAWARE BAY. THE OFS, HOWEVER,
SUGGEST THOSE DEPARTURES WOULD DIMINISH AS THE NORTH FLOW
DIMINISHES, AND SO WE THINK IT IS LIKELY THAT WE WILL AVOID ANY
FLOODING THIS EVENING. WE WILL MAINTAIN A MENTION IN THE HWO IN
THE INTEREST OF CAUTION.
AFTER THAT, THE COMBINATION OF THE APPROACHING SPRING TIDES WITH THE
FULL MOON AND THE EKMAN SPIRAL EFFECT FROM THE LIKELY AND
PREDOMINATELY NORTHERLY WINDS NEAR THE COAST MAY CAUSE MINOR TIDAL
FLOODING WITH THE EVENING AND OVERNIGHT HIGH TIDE CYCLES FROM FRIDAY
EVENING INTO THE WEEKEND. BY SATURDAY, WE WILL ONLY NEED DEPARTURES
OF ABOUT HALF A FOOT ABOVE NORMAL TO REACH THE CRITERIA. IN UPPER
DELAWARE BAY, THE TIDAL DELAWARE RIVER AND CHESAPEAKE BAY, THE
NORTHERLY FLOW COUPLED WITH NORMAL OR BELOW NORMAL FRESHWATER RUNOFF
SHOULD MITIGATE ANY TIDAL RELATED PROBLEMS.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...FREEZE WARNING FROM 3 AM TO 8 AM EDT FRIDAY FOR PAZ060>062.
NJ...FREEZE WARNING FROM 3 AM TO 8 AM EDT FRIDAY FOR NJZ007>010-
020>022-027.
DE...NONE.
MD...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...NIERENBERG
NEAR TERM...DELISI/GIGI/KLINE
SHORT TERM...DELISI/GIGI
LONG TERM...NIERENBERG
AVIATION...GIGI/KLINE/NIERENBERG
MARINE...DELISI/GIGI/NIERENBERG
FIRE WEATHER...DELISI
TIDES/COASTAL FLOODING...DELISI
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
322 PM EDT Thu Apr 5 2012
...SEVERE THUNDERSTORM WATCH IN EFFECT UNTIL 10 PM EST OR 9 PM CST
FOR MOST OF THE FORECAST AREA...
.MESOSCALE UPDATE...
Thus far we have not seen a consistent squall line along the leading
edge of the cold pool in central Alabama (now roughly along the I-65
corridor). The thunderstorms have fluctuated in intensity. We
currently appear to be in a reorganization phase with numerous
updrafts forming in the past 60-90 minutes along the leading edge of
the advancing cold pool. While the storms have generally not been
"severe" intensity in the past hour or so, peak winds at a few
observations along I-65 have been in the 25 to 40 knot range so the
thunderstorms have been producing some strong winds.
What the future holds for the developing MCS is still a bit of a
mystery. The environment is generally supportive of severe weather
with SBCAPE values around 1000-1500 j/kg and about 40-50 knots of
effective shear. However, the cloud top sampling tool on recent IR
satellite frames suggests that storms are not accessing all of the
potential instability. Sampled satellite cloud tops are about 5000
feet below RUC forecast equilibrium level heights along most of the
length of the squall line. Therefore, there is likely some sort of
environmental factors at play which are limiting the overall
strength of the storms. The storms are now entering an area along
and east of I-65 which saw fairly widespread cloud cover during the
late morning hours, and it`s possible that influenced the rate of
destabilization. Radar loops from KTLH also suggested the presence
of one or more MCVs behind convection in the northeast Gulf of
Mexico, and there may be some localized subsidence around the
periphery of the associated mid-upper level cloud shield.
Therefore, severe weather potential may be more isolated that much
of the model guidance had originally indicated. However, the
combination of instability and shear, as well as the close approach
of a potent upper level low support some threat of severe weather
into the evening hours. A Severe Thunderstorm Watch has recently
been issued for parts of our area to address this threat.
&&
.NEAR TERM (THROUGH TONIGHT)...
The main squall line continues to develop across portions of
south-central Alabama, and this will affect the forecast area
through the evening hours with strong to severe thunderstorms
expected. The current extrapolation of the main line places it over
southeast Alabama during the mid-afternoon hours and over towards
Valdosta around or after 8 pm. However, scattered convection will
develop ahead of this line which will have to be monitored as well.
Steep lapse rates and a moderately unstable airmass will promote the
risk of large hail and damaging winds.
.SHORT TERM (FRIDAY THROUGH SATURDAY NIGHT)...
The primary vort lobe will be east of the area Friday morning with
the associated cold front pushing into the northern portion of the
FL Peninsula before 12Z. We kept in a very low PoP for TS along the
boundary for a couple of hours Friday morning. However, it is quite
possible that all of the convection will be southeast of the area by
the start of the period. A secondary surge of cooler air will push
across the area behind a back door cold front Friday afternoon. High
pressure will then build southeast from the Great Lakes to our
forecast area by Saturday night. Therefore, this period will be
dominated by fair weather and cooler temperatures than we have seen
for quite some time. Highs on Friday will top out at 80 in the
warmest locations in FL with most areas seeing highs in the 70s. In
fact, areas northeast of Adel may not even reach 70. Lows Friday
night will dip into the 40s across most of the forecast area and in
some cases will get colder than we have seen in over a month. Highs
on Saturday will rebound nicely into the comfortable mid 70s will
low humidity. Saturday night should see temps reach the lower 40s
over our GA and inland FL Big Bend zones, the coldest readings since
March 5th.
.LONG TERM (SUNDAY THROUGH NEXT THURSDAY)...
A weak, mostly dry cold front will move southeast through the region
Sunday afternoon and evening as a fairly deep long wave trough
begins to take shape over the eastern CONUS to start the new week.
Another cold front (even drier than the first) will quickly pass
through our area Monday, further enhancing the cooling trend. The
latest ECMWF runs have joined the GFS in forecasting a significant
cool down for the eastern CONUS, with the 850 mb freezing line
reaching central GA Tuesday morning. Thereafter the GFS and ECMWF
diverge, as the ECMWF forecasts the deep long wave trough to
essentially cut off over GA while the GFS quickly reverts back to a
500 mb pattern resembling the current one over the CONUS. Despite
these differences, neither solution would result in a significant
rain event for our forecast area (though a few slight chance events
are possible as minor disturbances rotate through the broader
longwave trough).
As for temperatures, both solutions indicate a return to more
seasonal temperatures, with highs in the 70s, lows in the 40s, and
much lower humidity. Depending on how the details play out,
temperatures could be even a little cooler than this. It looks like
we`re finally going to get our early March weather...a month
late.
&&
.MARINE (TONIGHT THROUGH TUESDAY)...
West to southwest winds will shift to offshore behind a cold front
overnight and increase to exercise caution levels before daybreak.
There will be some decrease in wind speeds during the day on Friday.
However, a second cold front will cross the region late in the day
switching winds to the northeast and increasing them to advisory
levels by Friday night. Winds and seas will then decrease to below
headline criteria by Saturday afternoon as high pressure settles
south over the marine area. The high will then settle south of the
area switching winds to onshore and keeping them light.
&&
.AVIATION (THROUGH 18Z FRIDAY)...
Current extrapolation of the developing squall line in Alabama
places it near KDHN between 20-22z and KECP between 21-23z. The TAF
sites farther east will see later arrival times. Scattered
convection will likely also develop ahead of the line and could
affect areas prior to the arrival of the main squall line. Some of
this convection could be severe with hail and strong to severe wind
gusts.
&&
.FIRE WEATHER...Once the numerous to widespread showers and
thunderstorms exit the region tonight and early Friday, much cooler
and drier air will rush into the region from the northwest. While
afternoon relative humidities are now expected to remain above
critical levels at all areas on Friday, much lower values are
expected across the Tri-State region on Saturday. With this in mind,
a Fire Weather Watch or Red Flag Warning may be needed in future
forecasts for parts of the area on Saturday. This need will likely
be dependent on other resultant variables (such as ERCs,
Dispersions, 20 foot wind speeds, and Fuel Moisture) falling into
place by Saturday afternoon. These dry conditions will likely last
through Sunday, so additional watches or warnings could be
forthcoming.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 61 79 46 76 42 / 70 10 0 0 0
Panama City 63 80 55 75 53 / 70 10 0 0 0
Dothan 57 76 49 75 48 / 60 10 0 0 0
Albany 58 72 44 76 44 / 70 10 0 0 0
Valdosta 60 75 46 75 43 / 70 20 0 0 0
Cross City 63 80 49 77 44 / 70 20 0 0 0
Apalachicola 65 78 54 73 51 / 70 10 0 0 0
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
AL...None.
GA...None.
FL...None.
GM...None.
&&
$$
Mesoscale Discussion...Lamers
Short Term/Marine...Wool
Fire Weather...Gould
Long Term...Fournier
AREA FORECAST DISCUSSION
NWS BOISE ID
239 PM MDT THU APR 5 2012
.SHORT TERM...TONIGHT THROUGH SATURDAY...UPPER LEVEL LOW AXIS
CONTINUES TO OUR WEST WITH A MOIST IMPULSE PINWHEELING
PRECIPITATION INTO SE OREGON. MESONET AMOUNTS OF 0.10 OR GREATER
HAVE BEEN NEAR THE SW HARNEY-LAKE COUNTY LINE. SURFACE FLOW WILL
CONTINUE FROM THE NW WHICH WILL SUPPORT TERRAIN ENHANCEMENT OVER
SE OREGON AND OWYHEE COUNTY THROUGH MIDNIGHT...WITH MOST OF THE
P-TYPE BEING SNOW SHOWERS. LIGHT SHOWERS WERE ALSO POSSIBLE UNDER
RADAR ECHOES AND/OR BRIGHTER/COLDER CLOUD TOPS IN CENTRAL
IDAHO...THE SOUTHERN SAWTOOTH MOUNTAINS AND ACROSS BAKER COUNTY.
THESE NORTHERN AREAS WERE SEEING A FEW HUNDREDTHS REPORTED BUT BY
RAWS. RUC IS NOT SHOWING MORE THAN 100 CAPE IN THE CWFA AND LATEST
NAM12 SOUNDING AT BOISE IS CAPPED SO DID NOT ADD IN THUNDERSTORMS
AFTER 00Z BUT LEFT THEM IN ACROSS MAINLY OREGON AND THE PAYETTE
NATIONAL FOREST/OWYHEE MOUNTAINS THIS AFTERNOON. REMAINING COOL
WITH HIGHS 10 DEGREES BELOW NORMAL THROUGH FRIDAY AND TWO MORE
FROSTY NIGHTS IN THE VALLEY BEFORE TEMPERATURES REBOUND TO NEAR
NORMAL SATURDAY AS THE WELL ADVERTISED RIDGE STARTS TO PROGRESS
OVER THE AREA.
.LONG TERM...SATURDAY NIGHT THROUGH THURSDAY...SIGNIFICANT WARMING
STILL ON TRACK FOR THIS WEEKEND THROUGH TUESDAY AS AN UPPER LEVEL RIDGE
BUILDS IN OVER THE WESTERN US. THE RIDGE BECOMES HIGHLY AMPLIFIED...PEAKING
ON MONDAY...IN RESPONSE TO A CYCLONE OVER EASTERN NOAM DEEPENING THROUGH
THE PERIOD. TEMPERATURES LOOK TO BE 10-15 DEGREES ABOVE NORMAL THROUGH
TUESDAY...WITH THE WARMEST TEMPS COMING MONDAY. THE UPPER TREASURE VALLEY
COULD REACH 20 DEGREES ABOVE NORMAL WITH STRONG ENOUGH DOWNSLOPE WARMING
IN A SOUTHEAST WIND. HEIGHTS BEGIN TO COME DOWN LATE TUESDAY AHEAD OF A
SHORTWAVE TROUGH MOVING ONSHORE. THIS TROUGH WILL AFFECT THE AREA THROUGH
THE END OF THE FORECAST PERIOD...BRINGING A CHANCE OF RAIN SHOWERS TO MOST
LOCATIONS AND LOWERING TEMPS BACK DOWN NEAR NORMAL.
&&
.AVIATION...VFR...SCATTERED TO BROKEN MID AND HIGH LEVEL CLOUDS THIS
AFTERNOON WITH WIDELY SCATTERED SHOWERS WITH ISOLATED MVFR SNOW
SHOWERS AND MOUNTAIN OBSCURATION OVER THE HIGHER TERRAIN. CAN NOT
RULE OUT ISOLATED THUNDERSTORMS THIS AFTERNOON AND INTO THE EVENING
HOURS MAINLY ACROSS EASTERN OREGON. SURFACE WINDS WILL BE WESTERLY UP
TO 15 KNOTS THIS AFTERNOON AND EVENING. WINDS ALOFT WILL BE NORTHWESTERLY
10-15 KNOTS UP TO 10K FEET MSL.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.
&&
$$
WEATHER.GOV/BOISE
SHORT TERM...VM
LONG TERM....CB/WH
AVIATION.....CB
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
511 PM CDT THU APR 5 2012
.DISCUSSION...
258 PM CDT
THE MAIN FORECAST CONCERNS WILL BE THE FREEZING CONDITIONS TONIGHT
ACROSS MOST OF THE AREA.
SKIES ARE BECOMING MOSTLY CLEAR ACROSS NORTHERN ILLINOIS THIS
AFTERNOON AS THE MAIN AREA OF HIGHER LEVEL CLOUDINESS SHIFTS SOUTH
ALONG WITH THE MID LEVEL CIRCULATION ACROSS EAST CENTRAL AR. SURFACE
HIGH PRESSURE CENTERED OVER ONTARIO...EARLY THIS AFTERNOON...WILL
BEGIN TO BUILD SOUTHWARD ACROSS THE WESTERN GREAT LAKES TONIGHT.
THIS LOOKS TO SET THE STAGE FOR A WIDESPREAD FREEZE ACROSS THE AREA
OVERNIGHT TONIGHT AS A DRY AND COOL AIR MASS HAS SET UP ACROSS
NORTHERN ILLINOIS AND NORTHWESTERN INDIAN. IT APPEARS WINDS WILL NOT
BECOME TOTALLY CALM OVERNIGHT. INSTEAD IT APPEARS THAT A LIGHT
NORTHEASTERLY FLOW AT OR UNDER 5 KT WILL CONTINUE FOR MUCH OF THE
NIGHT AS WE REMAIN JUST SOUTH OF THE CENTER OF THE HIGH. THIS MAY
LIMIT THE AMOUNT OF FROST ACCRETION...EXCEPT FOR PROTECTED AREAS.
I AM EXPECTING TEMPERATURES TO DROP INTO THE UPPER 20S ACROSS NORTH
CENTRAL ILLINOIS FROM THE FOX VALLEY WESTWARD. THIS IS WHERE THE
COLDEST TEMPERATURES SHOULD OCCUR. I HAVE CHOSEN TO UPGRADE THE
FREEZE WATCH TO A WARNING FOR THE ENTIRE AREA. WARMER CONDITIONS
WILL PREVAIL ACROSS THE IMMEDIATE CHICAGO AREA...WITH TEMPERATURES
LIKELY ONLY BOTTOMING OUT IN THE THE UPPER 30S TO NEAR 40 DOWNTOWN.
IN SPITE OF THIS...I HAVE CHOSEN TO INCLUDE COOK COUNTY IN THE
FREEZE WARNING FOR AREAS ACROSS NORTHWESTERN SECTIONS OF THE COUNTY
WHERE NEAR TO JUST BELOW FREEZING CONDITIONS LOOK LIKELY.
COOL CONDITIONS WILL CONTINUE ON FRIDAY AS THE SURFACE HIGH SLOWLY
SHIFTS SOUTHWARD ACROSS LAKE MICHIGAN. ANOTHER COLD NIGHT LOOKS TO
SET UP FRIDAY NIGHT...WITH FREEZING TEMPERATURES AGAIN QUITE
POSSIBLE AS LIGHT WINDS SET UP ACROSS NORTHWESTERN INDIANA AND
NORTHEASTERN ILLINOIS.
A WARM UP LOOKS TO OCCUR ON SATURDAY AS A POTENT STORM SYSTEM MOVES
ACROSS NORTH DAKOTA AND MANITOBA. THIS SHOULD SETUP SOUTHERN FLOW
ACROSS THE AREA AND LEAD TO TEMPERATURES REBOUNDING BACK INTO THE
60S AREA WIDE. IT APPEARS THERE IS STILL A CHANCE OF SOME SHOWERS
AND POSSIBLY SOME THUNDERSTORMS SATURDAY NIGHT AS A COOL FRONT
PUSHES ACROSS THE AREA. MEAGER MOISTURE RETURN AND LARGE SCALE
FORCING FOR ASCENT THIS FAR SOUTH SHOULD LIMIT THE OVERALL THREAT
FOR THUNDERSTORMS. HOWEVER...I CANNOT RULE OUT A FEW SHOWERS
AFFECTING THE AREA DURING THIS TIME. THEREFORE I CONTINUED THE
CHANCE MENTION ON SATURDAY NIGHT.
IT APPEARS THAT NOT MUCH COLDER AIR WILL FILTER ACROSS THE REGION
BEHIND THE INITIAL FRONTAL PASSAGE SATURDAY NIGHT.
THEREFORE...SUNDAY APPEARS TO BE ANOTHER FAIRLY MILD DAY...WITH
TEMPERATURES ONCE AGAIN GETTING INTO THE 60S IN MOST AREAS WITH
WESTERLY FLOW.
THE MID LEVEL SHORT WAVE ACROSS THE NORTHERN PLAINS IS FORECAST TO
DIG ACROSS THE GREAT LAKES REGION EARLY NEXT WEEK. AS THIS
OCCURS...ANOTHER STRONGER COLD FRONT WILL PUSH ACROSS THE AREA BY
MONDAY MORNING. THIS FRONT WILL USHER IN A MUCH COOLER AIR MASS. SO
THE MAIN STORY EARLY NEXT WEEK WILL BE THE COOLER WEATHER. HIGH
TEMPERATURES WILL LIKELY BE LIMITED TO THE UPPER 40S TO THE LOWER
50S...AND OVERNIGHT LOW TEMPERATURES LOOK TO DIP BELOW
FREEZING...ESPECIALLY ON WEDNESDAY NIGHT AS A SURFACE RIDGE OF HIGH
PRESSURE BUILDS ACROSS THE AREA.
KJB
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 22Z...
* NORTHEAST WIND GUSTS
//DISCUSSION...UPDATED 22Z...
SOME CONCERN THAT THERE MAY BE SOME LAKE EFFECT CLOUD DEVELOPMENT
OVERNIGHT. RUC SOUNDINGS AND 925 MB RH FIELDS REALLY SATURATE
AROUND THE 1.5 KFT LAYER. WHILE THERE IS A LITTLE LAKE INSTABILITY
THAT COULD ALLOW A FEW CLOUDS TO POP...WOULDNT EXPECT IT TO BE ANY
THICKER THAN FEW...BUT ALSO BELIEVE THAT THE RUC IS REALLY
OVERDOING THIS FEATURE AND THAT THE ATMOSPHERE WILL BE FAR TO DRY
TO SUPPORT ANY CLOUDS AND NAM/HRRR TRENDS CONTINUE TO SUPPORT THIS.
WILL LEAVE THE 22Z AMD AS IS WITH NO MENTION OF OVERNIGHT CLOUDS.
SHEA
PREVIOUS 18Z DISCUSSION...
MAIN FORECAST CONCERN REMAINS GUSTY NORTHEAST WINDS...WHICH WILL
CONTINUE INTO EARLY THIS EVENING. GUSTS MAY DIMINISH WITH SUNSET
WITH SUSTAINED WINDS SLOWLY DIMINISHING DURING THE MID/LATE
EVENING HRS WITH SPEEDS WELL UNDER 10KTS OVERNIGHT. WINDS TURN A
BIT MORE EASTERLY FRIDAY MORNING AND MAY INCREASE BACK UP 10-12
KTS.
LATEST VISIBLE SATELLITE IMAGES SUGGEST CU/STRATOCU COVERAGE IS
FEW AT BEST ACROSS FAR NORTHEAST IL AND WITH NO ADDITIONAL LOW
CLOUD DEVELOPMENT EXPECTED...WILL REMOVE FROM THE TAFS. OTHERWISE
CIRRUS WILL CONTINUE TO THIN LEAVING SKC BY THIS EVENING. CMS
//ORD AND MDW CONFIDENCE...UPDATED 22Z...
* HIGH CONFIDENCE WITH EVENING WIND SPEED/DIRECTION/GUSTS
* LOW
//OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z...
FRIDAY NIGHT...VFR.
SATURDAY...CHANCE OF SHRA/TSRA LATE...ELSE VFR.
SUNDAY...VFR.
MONDAY...SLT CHC OF SHRA...ELSE VFR.
TUESDAY...MVFR POSSIBLE.
WEDNESDAY...VFR.
BMD
&&
.MARINE...
207 PM CDT
HIGH PRESSURE CENTERED OVER ONTARIO AND THE NORTHERN LAKES WILL
SLIDE SLOWLY SOUTHEAST THROUGH FRIDAY...ALLOWING NORTHEAST WINDS
CURRENTLY GUSTING TO 20-25 KTS TO SLOWLY DECREASE ACROSS LAKE
MICHIGAN AS THE SOUTHERN PERIPHERY OF THE SURFACE RIDGE BUILDS
ACROSS THE LAKE. THE RIDGE WILL MOVE EAST OF THE LAKE BY EARLY
SATURDAY...ALLOWING WINDS TO BECOME SOUTH-SOUTHEAST AND INCREASE
INTO THE 15-20 KT RANGE ESPECIALLY ON THE WEST SIDE OF THE LAKE BY
SATURDAY AFTERNOON AS LOW PRESSURE LIFTS FROM THE NORTHERN HIGH
PLAINS INTO SOUTHERN MANITOBA. A COLD FRONT ARCING SOUTH FROM THIS
LOW WILL PUSH EAST ACROSS THE LAKE SATURDAY NIGHT.
THE CANADIAN LOW WILL REDEVELOP/COMBINE WITH ANOTHER AREA OF LOW
PRESSURE OVER NEW ENGLAND AND THE ST LAWRENCE VALLEY SUNDAY AND
SUNDAY NIGHT...WHILE STRONG HIGH PRESSURE DEVELOPS OVER CENTRAL
CANADA. THIS WILL RESULT IN A PUSH OF COLDER AIR AND A PERIOD OF
BLUSTERY NORTH-NORTHWEST WINDS OF 25-30 KTS ACROSS THE LAKE EARLY
NEXT WEEK.
FOR THE ILLINOIS/NORTHWEST INDIANA NEARSHORE WATERS...WILL BE
EXTENDING SMALL CRAFT ADVISORIES INTO FRIDAY MORNING...AS PROLONGED
PERIOD OF SLOWLY DIMINISHING NORTH-NORTHEAST FLOW WILL MAINTAIN
WAVES 4 FT OR GREATER THROUGH THAT TIME.
RATZER
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...FREEZE WARNING...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010-
ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022-
ILZ023-ILZ032-ILZ033-ILZ039...1 AM FRIDAY TO 8 AM FRIDAY.
IN...FREEZE WARNING...INZ001-INZ002-INZ010-INZ011-INZ019...1 AM
FRIDAY TO 8 AM FRIDAY.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 10 AM FRIDAY.
&&
$$
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
425 PM CDT THU APR 5 2012
...UPDATE TO SYNOPSIS AND SHORT TERM...
.SYNOPSIS...
ISSUED AT 422 PM CDT THU APR 5 2012
A SLOW MOVING FAIRLY BAROTROPIC CLOSED LOW WAS DRIFTING ACROSS THE
SOUTHEAST PLAINS REGION THIS MORNING, HEADING TOWARD THE LOWER
MISSISSIPPI VALLEY. WEAK NORTHEAST SURFACE FLOW DOMINATED MUCH OF
WESTERN KANSAS WITH LOW STRATUS REMAINING IN PLACE THROUGH THE DAY.
THE LOW STRATUS IMPEDED DIURNAL WARMING SO MUCH THAT TEMPERATURES
HAD ONLY REACHED THE UPPER 40S TO MID 50S BY EARLY AFTERNOON.
&&
.SHORT TERM...(THIS EVENING THROUGH TOMORROW)
ISSUED AT 422 PM CDT THU APR 5 2012
AS DIURNAL HEATING CONTINUES THROUGH THE AFTERNOON, THE LOW LEVEL
THINNING STRATUS DECK WILL LIKELY SEE SOME BREAKS, AND THUS SOME AREAS
OF SUN MIGHT DEVELOP BY LATE IN THE DAY. THIS IS MOST LIKELY TO OCCUR
ACROSS THE EXTREME FAR SOUTHWEST SECTIONS OF WESTERN KANSAS, FROM
AROUND SYRACUSE TO HUGOTON. HOWEVER, PEAK HEATING WILL HAVE ALREADY
OCCURRED, SO IT APPEARS THE CURRENT RUC MAX TEMPERATURE FORECAST HAS
A GOOD HANDLE ON THE TREND. AS DIURNAL COOLING DEVELOPS AGAIN THIS
EVENING, IT WOULD FOLLOW THAT THE STRATUS LAYER WILL LIKELY BEGIN TO
EXPAND ONCE AGAIN GOING INTO TONIGHT. FOR TONIGHT, WITH ABUNDANT
CLOUD COVER AND LITTLE NOTICEABLE TEMPERATURE TENDENCY, THE
OVERNIGHT LOWS CAN BE AGAIN EXPECTED TO BE FAIRLY MILD, OR ABOUT
5-10 DEGREES ABOVE NORMAL FOR EARLY APRIL. THE FORECAST PROBLEM OF
THE OVERNIGHT WILL THEN BECOME, FOG AND EVEN PERHAPS THE
REDEVELOPMENT OF DRIZZLE ACROSS WESTERN KANSAS, AS THE LEAD
APPROACHING UPPER JET NOW ACROSS THE GREAT BASIN APPROACHES OUT
REGION. AS A RESULT OF THE INCREASING UPPER LEVEL CROSS BARRIER
FLOW, SURFACE PRESSURE FALLS WILL OCCUR ALONG THE LEE OF THE
MOUNTAINS BY LATE TONIGHT, INCREASING THE LOW LEVEL PRESSURE
GRADIENT ACROSS WESTERN KANSAS. THE GRADIENT WILL SUPPORT STRONG
BREEZY TO WINDY CONDITIONS ON FRIDAY. THE LINGERING CLOUD COVER AND
ADDITIONAL CIRRIFORM CLOUDS MAY ACT TO FURTHER INHIBIT MIXING. MODEL
10M WINDS ARE GENERALLY FORECASTING NEAR 20 KNOTS OF SURFACE
SUSTAINED WINDS IN ACROSS THE LARGER PART OF WESTERN KANSAS, AND THE
GFSMOS IS EVEN STRONGER. OVERNIGHT AND EARLY MORNING DRIZZLE IS MOST
LIKELY TO BE SEEN ACROSS NORTHWEST KANSAS, HOWEVER MODEL
THERMODYNAMIC PROFILES SUPPORT IT EVEN OVER A LARGE PART OF
SOUTHWEST KANSAS. CONVECTIVE CHANCES BECOME INCREASED ALONG A
DRYLINE OVER THE WESTERN COUNTIES (CLOSELY TIED TO THE COLORADO
LINE) IN THE EARLY AFTERNOON AS DIURNAL HEATING AS WELL AS STRONG
POSITIVE TEMPERATURE TENDENCY ACT TO INCREASE CONVECTIVE AVAILABLE
POTENTIAL ENERGY OVER WESTERN KANSAS. ALTHOUGH WIDESPREAD SEVERE
WEATHER IS NOT EXPECTED, AN ISOLATED SEVERE HAIL STORM OR TWO CANNOT
BE RULED OUT IN THE AFTERNOON.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 255 PM CDT THU APR 5 2012
AS THE LARGE UPPER LEVEL LOW OVER ARKANSAS EXITS OUR AREA TO
EAST-SOUTHEAST TONIGHT AND FRIDAY, A HIGH AMPLITUDE RIDGE WILL BUILD
IN OVER THE PLAINS FRIDAY NIGHT AND SATURDAY. THIS SAID, THERE IS
CONSIDERABLE UPPER LEVEL INSTABILITY OVER SOUTHWEST KANSAS AS A MID
LEVEL WAVE SWINGS THROUGH FROM THE SOUTHWEST. THEREFORE, WILL HAVE
16-20 PERCENT POPS IN OUR EASTERN CWA FOR SLIGHT CHANCES OF
THUNDERSTORMS FRIDAY EVENING AND FRIDAY NIGHT. SLIGHT CHANCES WILL
LINGER IN OUR SOUTHEASTERN CWA, DUE MAINLY TO A FRONTAL BOUNDARY
WHICH WILL MIGRATE EASTWARD SATURDAY MORNING. AN UPPER HIGH
PRESSURE RIDGE BUILDS INTO THE WESTERN ROCKIES SUNDAY INTO
THURSDAY. A SURFACE FRONT SHOULD SLIDE NORTHWARD FROM OKLAHOMA AS A
WARM FRONT TUESDAY INTO WEDNESDAY, AND BRING ANOTHER ROUND OF
THUNDERSTORMS TO FIRST OUR SOUTHERN COUNTIES TUESDAY NIGHT, AND BY
WEDNESDAY FARTHER NORTH TO OUR CENTRAL COUNTIES. THE GFS MODEL IS A
LITTLE FASTER AND FARTHER NORTH WITH THIS WARM FRONT ON TUESDAY AND
WEDNESDAY, BUT FOR NOW I LIKE THE SLOWER, MORE SOUTHERN TRACK OF THE
ECMWF MODEL. BY THURSDAY, THE FRONT SHOULD BE BISECTING OUR CWA AND
AFTERNOON THUNDERSTORMS HAVE LITTLE BETTER CHANCE OF FORMING IN THE
WARM SURFACE AIR AND WITH THE FRONT SERVING AS FOCUS BOUNDARY.
LOADED THE CREXTENDFCST_INIT PROCEDURE`S QPF, AND THE AMOUNTS SEEMED
QUITE HIGH FOR THE EXTENDED PERIOD. DECREASED THE TUESDAY NIGHT
INTO THURSDAY QPF QUITE A BIT.
TEMPERATURES ARE ANOTHER IMPORTANT PART OF THIS PACKAGE. SUNDAY
MORNING LOOKS COLD ENOUGH SOME PATCHY FROST. WINDS WILL BE LIGHT,
SKIES WILL BE CLEAR, AND THE LOW LEVEL FLOW DOWN THE GEOGRAPHIC
DOWNSLOPE PATTERN SHOULD BRING MID 30S FOR MIN T`S IN OUR NORTHWEST
AND WEST. IF THE MODELS GET ANY COLDER DURING THE NEXT COUPLE OF
MODEL RUNS, COULD SEE A FROST ADVISORY NEEDED SOMEWHERE IN OUR
NORTHWESTERN CWA FOR SUNDAY MORNING. IN THE NEARER TERM, FRIDAY
NIGHT`S LOWS WILL BE IN THE MID 40S WEST TO THE MID 50S SOUTHEAST,
IN THE MID TO UPPER 40S MONDAY MORNING, DIP TO THE UPPER 30S TO MID
40S TUESDAY MORNING, THEN REBOUND TO THE 45 TO 50F DEGREE RANGE BY
BOTH WEDNESDAY AND THURSDAY. MAXIMUM TEMPERATURES WILL START OUT IN
THE MID TO UPPER 60S SATURDAY, SUNDAY AND MONDAY, BUT LOWER TO THE
MID 60S MONDAY, BEFORE WARMING UP IN OUR SOUTHWEST WED AND THUR INTO
THE LOWER 70S AS WARM FRONT BULGES NORTHWARD, WITH LOWER 60S HIGH IN
THE EASTERN CWA.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 108 PM CDT THU APR 5 2012
WIDESPREAD MVFR/IFR STRATUS CLOUDS ARE AFFECTING THE REGION THIS
AFTERNOON. ALTHOUGH MODELS TEND TO DECREASE THE AFTERNOON BOUNDARY
LAYER RELATIVE HUMIDITY, THE SATELLITE IMAGERY TRENDS ACROSS WESTERN
KANSAS AND METAR OBSERVATIONS OF CEILINGS INDICATE A PESSIMISTIC
OUTLOOK FOR THE REMAINDER OF THE AFTERNOON. AS A RESULT WE WILL
MAINTAIN A PERSISTENCE FORECAST, WITH CEILINGS DETERIORATING AGAIN
DIURNALLY OVERNIGHT INTO THE LIFR CATEGORIES.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 48 67 50 65 / 10 10 10 10
GCK 48 71 47 63 / 10 20 10 10
EHA 49 77 44 63 / 10 20 20 10
LBL 49 73 49 65 / 10 20 10 10
HYS 46 63 51 64 / 10 10 20 20
P28 48 65 55 67 / 10 10 20 20
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...RUSSELL
SHORT TERM...RUSSELL
LONG TERM...BURKE
AVIATION...RUSSELL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1221 PM MDT THU APR 5 2012
.UPDATE...
ISSUED AT 902 AM MDT THU APR 5 2012
UPDATED TO CANCEL THE DENSE FOG ADVISORY SINCE FOG HAS DIMINISHED
AND VISIBILITIES HAVE IMPROVED ACROSS THE AREA.
UPDATE ISSUED AT 547 AM MDT THU APR 5 2012
COMPLETED AN UPDATE NOT TOO LONG AGO. MAIN REASON FOR UPDATE WAS
TO REDEFINE DENSE FOG ADVISORY AREA. OBSERVATIONS SHOWING DENSE
FOG HAVE STAYED ROUGHLY ALONG AND WEST OF THE COLORADO BORDER. THE
HRRR FOLLOWED BY THE RUC WAS DOING VERY WELL WITH THIS. SO
CANCELLED THE EASTERN MOST ROW OF COUNTIES THAT WERE IN THE
ADVISORY. USED THE COMBINATION OF REALITY COMBINED WITH THE
MESOSCALE MODELS TO ADJUST THE HOURLY GRIDS THROUGH THE MORNING
HOURS.
&&
.SHORT TERM...(TODAY THROUGH SATURDAY NIGHT)
ISSUED AT 357 AM MDT THU APR 5 2012
FORECAST PROBLEMS WILL BE EXTENT OF FOG/STRATUS THROUGH TOMORROW
NIGHT AND ITS AFFECTS ON TEMPERATURES...CHANCES OF
CONVECTION/PRECIPITATION THROUGH FRIDAY NIGHT...AND WINDS FRIDAY
INTO SATURDAY. SATELLITE SHOWING AN AMPLIFIED/AMPLIFYING PATTERN
OVER THE NORTHERN HEMISPHERE WITH A SERIES OF TROUGHS FROM THE
PACIFIC INTO THE WESTERN ATLANTIC. SLOW MOVING UPPER LOW THAT BROUGHT
A LOT OF PRECIPITATION HAS FINALLY MOVED WELL EAST OF THE AREA. NEXT
UPPER TROUGH TO AFFECT OUR WEATHER IS DEEPENING ALONG THE WEST COAST
AT THIS TIME. SATELLITE/UPPER AIR WOULD INDICATE A LOT OF COLD AIR
WITH THIS SYSTEM.
AT JET LEVEL THE ECMWF AND NAM WERE DOING A LITTLE BETTER WITH THE
JET ASSOCIATED WITH THE NEW WESTERN TROUGH. THROUGH 06Z SATELLITE
AND UPPER AIR DATA SHOWED THAT ALL THE MODELS WERE CLOSE BUT THE
ECMWF AND NAM WERE DOING A LITTLE BETTER THAN THE REST. THE NAM AND
ECMWF WERE DOING WELL WITH THE SURFACE PRESSURE/WIND FIELD. THE
ECMWF...CANADIAN AND GFS WERE DOING THE BEST ON THE LOW LEVEL
THERMAL FIELD.
TODAY/TONIGHT...INITIAL PROBLEM WILL BE THE DENSE FOG ADVISORY IN
AFFECT AND HOW LONG THE STRATUS AND FOG LAST. WILL MONITOR TRENDS
FOR AS LONG AS POSSIBLE AND MAKE ANY ADJUSTMENTS IN THE ADVISORY OR
FOG AREA AS NEEDED. AT THIS TIME THE DENSE FOG HAS STAYED CONFINED
TO ALONG AND WEST OF THE COLORADO BORDER. GUIDANCE IS STARTING TO
HINT THIS WILL BE THE CASE. WILL CONTINUE TO MONITOR.
AM CONCERNED ABOUT THE EASTERN HALF OF THE AREA WARMING UP VERY MUCH
DUE TO POSSIBILITY OF CLOUDS LASTING A LONG TIME PLUS THE PREVAILING
EASTERLY UPSLOPE WINDS THROUGH THE DAY. LOWERED THE MAXES SOME BUT
STILL MAY NOT BE ENOUGH.
INTERESTING FORECAST FOR TONIGHT. MODELS STILL IN AGREEMENT IN
BRINGING IN AT THE VERY LEAST A WIDESPREAD STRATUS DECK. POSSIBLE
THAT THE AREA OF FOG/DENSE FOG COULD BE EVEN LARGER THAN THIS
MORNINGS. 06Z NAM EVEN MORE AGGRESSIVE IN DOING THIS THAN THE EARLIER
GUIDANCE. CURRENT PACKAGE HAS -SHRA/ELEVATED -TSRA FOR LATER TONIGHT.
MAIN UPPER JET REMAINS MUCH FURTHER WEST BY 12Z AS SHOWN YESTERDAY.
MODELS HINTING AT A WEAK LEFT FRONT QUADRANT OF THE UPPER AFFECTING
THE FAR WESTERN PORTION OF THE AREA AFTER 06Z. MODELS TENDED TO BE
TOO FAR EAST INITIALLY WITH THE MAIN AXIS. THINKING THAT THE MODELS
MAY BE TOO PROGRESSIVE WITH THE UPPER TROUGH AND ASSOCIATED BELIEVE
THE JET LIFT WILL BE A LITTLE FURTHER WEST THAN CURRENTLY INDICATED.
THERE IS WARM ADVECTION IN THE MID LAYERS. HOWEVER...SATELLITE AND
UPPER AIR ANALYSIS IS SHOWING A VERY DEEP AND DRY LAYER IN THE MID
LEVELS. LATEST MODEL GUIDANCE HAS SOME CINH IN PLACE AND ALSO NO
ELEVATED CAPE. GFS/NAM MODEL SOUNDINGS BOTH IN AGREEMENT THAT WILL
HAVE A SHALLOW SATURATED LOW LAYER WITH VERY DRY AIR ABOVE IT. SO
EVEN IF IT WERE UNSTABLE ENOUGH DOUBT THAT PARCELS COULD BECOME
SATURATED. SREF GIVES LITTLE TO NO PROBABILITY FOR MEASURABLE OR
CONVECTIVE PRECIPITATION. CONSIDERING WHAT THE SOUNDINGS ARE
SHOWING THINKING THEY ARE GENERATING DRIZZLE. AFTER SAYING ALL
THAT...WILL PUT IN AREAS OF FOG WITH PATCHY DRIZZLE. BECAUSE OF THE
INCREASING MOISTURE...WINDS AND CLOUD COVER WARMED MINS UP AND IT IS
POSSIBLE THAT I STILL MAY NOT BE WARM ENOUGH.
FRIDAY/FRIDAY NIGHT...MODELS/HPC GENERATE/PUT LIGHT QPF ACROSS THE
AREA DURING THE DAY...ESPECIALLY EARLY IN THE DAY. AGAIN THE SAME
REASON/ARGUMENT FOR THE WEATHER/CHANCE OF PRECIPITATION APPLIES TO
THE MORNING HOURS HERE. WILL CONTINUE THE AREAS OF FOG AND PATCHY
DRIZZLE.
MODELS DIFFER ON THE POSITION OF THE MAIN JET AND ALL IMPORTANT
LEFT FRONT QUADRANT. MODEL CLUSTERING WOULD TEND TO FAVOR TO START
THE LEFT FRONT QUADRANT NEAR THE SOUTHERN/SOUTHWEST PORTION OF THE
AREA AT 18Z AND THEN PROGRESS IT NORTH THROUGH THE AFTERNOON WITH
THE MAIN JET LIFT TO THE NORTH OF THE AREA BY LATE AFTERNOON. THE
NAM IS FURTHER SOUTH THAN ANYONE AND A LITTLE MORE FAVORABLE. THIS
CONTINUES INTO THE MIDDLE OF THE NIGHT. DRY LINE IS FURTHER WEST
THAN SHOWN YESTERDAY WHICH HAS BEEN THE TREND THE LAST FEW DAYS.
MODEL SOUNDINGS ARE NOT TERRIBLY MOIST. HOWEVER THERE LOOKS TO BE A
NARROW INSTABILITY AXIS NEAR THE COLORADO BORDER WITH NO CAP. WILL
HAVE THE JET AND DRY LINE CLOSE BY ALONG WITH INCOMING SHORTWAVE
TROUGH. SO ADJUSTED THE SLIGHT CHANCE OF THUNDERSTORMS TO NEAR THE
COLORADO BORDER/INSTABILITY AXIS. LIFT AND INSTABILITY SHIFT EAST
DURING THE NIGHT. ALSO FRONT MOVES THROUGH THE EASTERN HALF AFTER
06Z. SO TRANSITIONED THE SLIGHT CHANCE TO CHANCE POPS TO THE EAST
AS THE NIGHT PROGRESSES.
AGAIN THE MAIN PLAYER IN HOW WARM IT GETS WILL BE HOW LONG STRATUS
AND FOG LAST. FROM YESTERDAY...DRYLINE AND GREATER LOW LEVEL
MOISTURE/CLOUD COVER ARE FURTHER WEST THAN YESTERDAY. MODELS
CONSEQUENTLY HAVE LOWERED MAXES FROM YESTERDAY. SO I CONTINUED TO
PULL WARMER TEMPERATURES FURTHER TO THE WEST. FRONT LOOKS TO MOVE
THROUGH DURING THE LATE EVENING INTO THE OVERNIGHT HOURS.
WINDS BEHIND THE FRONT COULD INCREASE INTO THE BREEZY TO WINDY
CATEGORY FOR A BRIEF TIME PERIOD.
SATURDAY/SATURDAY NIGHT...STRONGEST WINDS LOOK TO BE BEFORE SUNRISE.
LOWER DEWPOINTS LOOK TO BE ADVECTED IN AS WELL. IT IS STILL TOO FAR
OUT TO PUT ANY FIRE WEATHER HIGHLIGHT EVEN IF I WANTED TO. BUT
DESPITE THE FAVORABLE WINDS AND DEWPOINTS BELIEVE THE FUEL MOISTURE
WILL STILL BE RATHER HIGH AFTER THE PREVIOUS RAIN.
WINDS DECOUPLE AND BECOME LIGHT SO MINS WILL MUCH COLDER THAN THEY
HAVE BEEN RECENTLY. POSSIBLE THAT SOME LOCATIONS COULD GET TO NEAR
FREEZING.
THANKS TO ALL THAT COLLABORATED.
.LONG TERM...(SUNDAY THROUGH THURSDAY)
ISSUED AT 357 AM MDT THU APR 5 2012
A FRONT WILL REMAIN STALLED SOUTH AND WEST OF THE CWA THROUGH THE
EXTENDED PERIOD WITH EASTERLY FLOW IN PLACE OVER NW KS AND SW
NEBRASKA. WEST OF STATIONARY FRONT WILL SEE SOUTHERLY FLOW WITH
WARMER TEMPS ALOFT. RESULT WILL BE GRADIENT IN TEMPS FROM WEST TO
EAST WITH WARMEST OVER EASTERN COLORADO AND COOLER EAST. NOT A LOT
OF CONFIDENCE IN TEMP FORECAST THROUGH THE EXTENDED PERIOD WITH THE
POTENTIAL FOR CLOUD COVER TO LIMIT NORMAL DIURNAL WARMING/COOLING
TRENDS. FOR NOW FORECAST SHOWS SEASONABLY MILD TEMPS IN THE
60S...NEAR 70 IN EASTERN COLORADO.
H5 RIDGE ALOFT WILL GENERALLY KEEP STABLE AIR MASS AND DRY
CONDITIONS EXPECTED THROUGH TUESDAY NIGHT. BY WEDNESDAY ISENTROPIC
UPGLIDE AND DEEP MOISTURE ADVECTION WILL OVERSPREAD THE AREA AS A
TROUGH DEEPENS ACROSS THE WESTERN US. WITH LARGE SCALE SUBSIDENCE
ALOFT AND STABLE AIRMASS IN PLACE IM NOT VERY CONFIDENT WE WILL SEE
MUCH IN THE WAY OF MEASUREABLE PRECIPITATION WEDNESDAY. GFS CONTINUES
TO SHOW DEEP MOISTURE IN PLACE ALONG WITH ISENTROPIC UPGLIDE...SO
SOME SHOWER ACTIVITY CANT BE RULED OUT WED. THUNDERSTORMS ALSO CANT
BE RULED OUT WED AFTERNOON ACROSS THE SOUTH AND WEST WHERE ELEVATED
CAPE IS CURRENTLY ADVERTISED ON BY GFS NEAR SURFACE BAROCLINIC ZONE.
FROM EXPERIENCE THIS SEEMS TO BE MORE OF A DRIZZLE/FOG PATTERN
ACROSS MUCH OF THE CWA...THOUGH THE GFS SOLUTION CANT BE DISCOUNTED.
THERE IS ENOUGH UNCERTAINTY AT THIS RANGE THAT I LEFT SLIGHT CHANCE
POPS IN PLACE WED THIS FORECAST CYCLE.
BY WED NIGHT/THURSDAY A NEGATIVELY TILTED UPPER TROUGH OVER THE
WESTERN US WILL BEGIN TO MOVE TOWARDS THE CWA...WITH A GREAT DEAL OF
SPREAD BETWEEN GUIDANCE ON THE TIMING OF THIS FEATURE AND HOW IT
EVOLVES. 00Z ECMWF IS MUCH SLOWER...STRONGER...AND FURTHER SOUTH.
THE GFS IS MORE PROGRESSIVE AND FURTHER NORTH. CONSIDERING THE
SPREAD IN GUIDANCE SLIGHT CHANCE POPS SEEMED LIKE A GOOD FIRST
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1155 AM MDT THU APR 5 2012
THE PRESSURE GRADIENT AND WINDS WILL INCREASE ACROSS THE REGION AS
HIGH PRESSURE STRENGTHENS OVER THE EASTERN PLAINS AND LOW PRESSURE
DEEPENS ALONG THE FRONT RANGE. AT BOTH KMCK AND KGLD...LOW CLOUDS
SHOULD MAINLY DISSIPATE THIS AFTERNOON WITH CONDITIONS STAYING
MVFR WITH POSSIBLE INTERMITTENT VFR. AFTER SUNSET LOW CLOUDS AND
FOG SHOULD BEGIN TO REDEVELOP WITH CONDITIONS BECOMING IFR BETWEEN
03Z AND 06Z. BETWEEN 09Z AND 11Z...EXPECT CONDITIONS TO LOWER TO
LIFR MAINLY DUE TO CEILINGS SOUTH WINDS ALSO INCREASE AND BECOME
GUSTY. EXPECT CONDITIONS TO IMPROVE TO IFR BETWEEN 16Z AND 18Z WITH
SOUTH WINDS REMAINING GUSTY.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
KS...NONE.
NE...NONE.
&&
$$
UPDATE...LOCKHART
SHORT TERM...BULLER
LONG TERM....DR
AVIATION...LOCKHART
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1248 PM CDT THU APR 5 2012
.AVIATION...18Z TAF ISSUANCE...
CLEAR SKIES AND VFR CONDITIONS WILL CONTINUE THROUGH THE NEXT 24
HOURS. SURFACE WINDS WILL REMAIN FROM THE EAST THIS AFTERNOON AND
VEER TO THE SOUTH BY TOMORROW MORNING. A WEAK LLJ WILL DEVELOP
ACROSS CENTRAL MN TONIGHT AND ALLOW FOR A BRIEF PERIOD OF LLWS AT
MOST TERMINALS.
&&
.PREV DISCUSSION... /ISSUED 629 AM CDT THU APR 5 2012/
AVIATION.../12Z TAF ISSUANCE/
MARGINAL LOW-LEVEL WIND SHEAR IS EXPECTED EARLY THIS MORNING AND
THEN AGAIN LATE TONIGHT. OTHERWISE VFR CONDITIONS ARE EXPECTED
ACROSS THE NORTHLAND THROUGH THE TAF PERIOD.
PREV DISCUSSION... /ISSUED 317 AM CDT THU APR 5 2012/
SHORT TERM...TODAY THROUGH FRIDAY.
AN UPPER LEVEL RIDGE AND SURFACE HIGH TO THE EAST/NORTHEAST WILL
PROVIDE PLENTY OF SUNSHINE AND DRY WEATHER THROUGH THE PERIOD.
IT WILL BE A BIT COOLER TODAY WITH ONSHORE WINDS CONTINUING AROUND
LAKE SUPERIOR. HIGHS WILL RANGE FROM 55 TO 60 WELL IN OUR
WESTERN/SOUTHERN ZONES...TO 45 TO 50 CLOSER TO LAKE SUPERIOR.
CLEAR SKIES TONIGHT AND LIGHT WINDS OVER CENTRAL AND EASTERN ZONES
WILL ALLOW TEMPERATURES TO DROP INTO THE TWENTIES FOR MOST AREAS.
MOSTLY SUNNY SKIES ON FRIDAY AND INCREASING SOUTHEASTERLY WINDS
WILL ALLOW TEMPS TO WARM INTO THE UPPER FIFTIES TO LOWER SIXTIES
WELL INLAND FROM LAKE SUPERIOR...WITH AREAS CLOSER TO LAKE
SUPERIOR COOLER DUE TO CONTINUED ONSHORE WINDS. THE SOUTH SHORE
WILL REACH THE MID FIFTIES TO AROUND SIXTY AS WINDS TURN MORE OUT
OF THE SOUTHEAST THROUGH THE DAY.
LONG TERM...FRIDAY NIGHT THROUGH WEDNESDAY.
A RIDGE OF HIGH PRESSURE OVER THE GREAT LAKES WILL MOVE OFF TO THE
EAST AND GIVE WAY TO A LOW PRESSURE SYSTEM OVER THE PLAINS WHICH IS
PROGGED TO LIFT NEWD OVER NWRN ONTARIO BY SATURDAY NIGHT. A TRAILING
COLD FRONT WILL SWEEP EWD ACROSS THE UPPER MIDWEST SATURDAY INTO
SATURDAY NIGHT...BRINGING A CHANCE OF SHOWERS AND POSSIBLY SOME
THUNDERSTORMS TO THE NORTHLAND. COOL AND BLUSTERY WEATHER WITH A
CHANCE OF RAIN/SNOW SHOWERS IS THEN EXPECTED FOR SUNDAY INTO MONDAY
AS THE PARENT UPPER LEVEL TROUGH MOVES ACROSS THE REGION. ANOTHER
RIDGE OF HIGH PRESSURE FROM CANADA WILL BUILD BACK OVER THE UPPER
MIDWEST...RESULTING IN DRIER CONDITIONS AND SEASONAL TEMPS.
AVIATION.../06Z TAF ISSUANCE/
THE RUC13 925MB WINDS AND NAM12 1000MB-950MB WINDS INDICATE SOUTHEAST
WINDS OF UP TO 30 KNOTS OVERNIGHT SO INCLUDED WIND SHEAR AT 1K AGL
THROUGH 12Z. VAD WIND PROFILES FROM DLH HAVE BEEN CONSISTENT THE
PAST TWO HOURS WITH 30 KNOT WINDS FROM THE SOUTHEAST ABOVE THE SURFACE.
OTHERWISE...VFR CONDITIONS WILL CONTINUE THROUGH THE TAF PERIOD.
&&
.POINT TEMPS/POPS...
DLH 28 56 34 53 / 0 0 10 50
INL 24 60 36 53 / 0 0 10 50
BRD 31 62 40 57 / 0 0 20 40
HYR 22 62 33 59 / 0 0 10 50
ASX 25 58 34 58 / 0 0 10 40
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
LS...SMALL CRAFT ADVISORY UNTIL 10 PM CDT THIS EVENING FOR LSZ144-145.
&&
$$
AVIATION...TENTINGER
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1236 PM EDT THU APR 5 2012
.SYNOPSIS...
A COLD FRONT WILL MOVE SLOWLY SOUTH ACROSS THE AREA TODAY. A WAVE OF
LOW PRESSURE WILL DEVELOP ALONG THE FRONT TO OUR SOUTHWEST AND THEN
MOVE OFFSHORE FRIDAY MORNING. SHOWERS AND THUNDERSTORMS WILL BE MOST
NUMEROUS ACROSS SOUTH CAROLINA THIS AFTERNOON...WHERE SOME COULD BE
STRONG TO SEVERE. RAIN IS EXPECTED TO DEVELOP ACROSS THE AREA
TONIGHT INTO FRIDAY. COOLER CONDITIONS WILL FOLLOW FOR THE WEEKEND
AS CANADIAN HIGH PRESSURE BUILDS ACROSS THE CAROLINAS. SEVERAL DRY
COLD FRONTS WILL MOVE ACROSS THE AREA NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 PM THURSDAY...THE COLD FRONT IS CURRENTLY LOCATED FROM
THE WESTERN END OF OAK ISLAND ACROSS NORTHERN HORRY COUNTY TO NEAR
MARION AND FLORENCE. EXCELLENT LOW LEVEL CONVERGENCE IS DEVELOPING
ALONG THE BOUNDARY WHERE SURFACE CAPE IS NOW 2500 J/KG AND EVEN THE
100-MB MIXED LAYER CAPE IS APPROACHING 2000 J/KG. ONCE THE
CONVECTIVE CAP GOES IN THE NEXT COUPLE OF HOURS WE EXPECT TO SEE
RAPID DEVELOPMENT OF THUNDERSTORMS ACROSS THIS AREA. THE MOST-RECENT
SPC OUTLOOK MAINTAINS PROBABILITIES FOR DAMAGING WINDS AND LARGE
HAIL AWAY FROM THE NC BORDER REGION OF SOUTH CAROLINA...IN-LINE WITH
OUT THINKING AS WELL. PREVIOUS DISCUSSION FROM 10 AM FOLLOWS...
A SOUTHWARD MOVING COLD FRONT IS MOVING THROUGH THE WILMINGTON AREA
AT THE CURRENT TIME...ACCOMPANIED BY A BANK OF LOW CLOUDS AND ABOUT
A 120-DEGREE CLOCKWISE WIND SHIFT FROM THE WEST TO NORTH-NORTHEAST.
HIGH TEMPERATURES HAVE ALREADY BEEN ESTABLISHED FOR THE DAY NORTH OF
THIS FRONT WHERE WE EXPECT TEMPERATURES TO STEADILY FALL THROUGH THE
60S THROUGH THE AFTERNOON HOURS. LINEAR EXTRAPOLATION OF THE FRONT
ON SATELLITE IMAGERY AGREES FAIRLY WELL WITH THE LATEST SEVERAL
(09Z,10Z,11Z) RUNS OF THE HRRR MODEL AND PLACE THE FRONT NEAR
SOUTHPORT...WHITEVILLE...DILLON AND BENNETTSVILLE JUST BEFORE
NOON...AND INTO THE MYRTLE BEACH AREA BY 2 PM.
PLENTY OF SUNSHINE IS WARMING AND DESTABILIZING THE AIRMASS OUT
AHEAD OF THE FRONT WHERE SKIES ARE CLEAR...AND WE ANTICIPATE
SURFACE-BASED CAPE TO GROW TO AS MUCH AS 2000 J/KG BY MID AFTERNOON.
GIVEN THE STRONG LOW-LEVEL CONVERGENCE ALONG THE FRONT AND ONLY THE
BAREST HINT OF A CAPPING INVERSION AROUND 5000 FT STRONG TO LOCALLY
SEVERE THUNDERSTORMS SHOULD DEVELOP ALONG AND SOUTH OF THE FRONTAL
POSITION AT THAT TIME...ROUGHLY DARLINGTON TO FLORENCE...MARION AND
CONWAY TO MYRTLE BEACH. THE STRONGEST 0-6 KM BULK SHEAR VALUES WILL
REMAIN WELL NORTH OF THE SURFACE FRONT ACROSS NORTHERN AND CENTRAL
NORTH CAROLINA...BUT SUFFICIENT SHEAR SHOULD STILL EXIST FOR MODEST
STORM ORGANIZATION WITH ISOLATED DAMAGING WINDS OR LARGE HAIL THE
PRIMARY THREATS EXPECTED.
&&
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 3 AM THURSDAY...MID LEVEL LOW WILL BE MOVING ACROSS SOUTHERN
SOUTH CAROLINA AT THE BEGINNING OF THE PERIOD WITH THE SURFACE LOW
OFFSHORE OF THE GEORGIA/SOUTH CAROLINA BORDER. ISENTROPIC LIFT WILL
COME TO AN END IN THE MORNING HOURS LEAVING A SMALL AREA OF MID
LEVEL FRONTOGENESIS AS THE MAIN FORCING MECHANISM. CONTINUED TO
ADVERTISE CATEGORICAL POPS THROUGH 1800 UTC WITH AN AXIS OF HIGHER
QPF FROM DILLON AND MARION COUNTIES EAST TO NEW HANOVER AND PENDER
COUNTIES CITING THE STRONGER FORCING.
FOCUS THEN SHIFTS TO TEMPERATURES AS MODEST COLD AIR ADVECTION
CONTINUES THROUGH 1800 UTC SATURDAY UNDER CLEAR/SUNNY SKIES. LATEST
MET NUMBERS APPEAR TOO COLD WITH 33 AND 36 IN LUMBERTON/WILMINGTON
FOR SATURDAY MORNING. LEANED TOWARD THE WARMER MAV NUMBERS AND EVEN
THERE I ADDED A DEGREE OR TWO AS THE BOUNDARY LAYER REMAINS MIXED.
IDEAL RADIATIONAL CONDITIONS OCCUR SUNDAY MORNING ALTHOUGH WITH AIR
MASS MODIFICATION AND A FULL DAY OF APRIL SUNSHINE TO FURTHER WARM
SOIL TEMPERATURES...FROST SHOULD NOT BE AN ISSUE.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 3 AM THURSDAY...PROGRESSIVE PATTERN IN PLACE THROUGH THE
PERIOD WITH THE CENTER OF ATTENTION BEING THE EAST COAST TROUGH. MID
LEVEL LOW RETROGRADES OVER QUEBEC MONDAY AND TUESDAY WITH A
SECONDARY SHORTWAVE MOVING ACROSS THE GREAT LAKES AND DIVING SOUTH
LATE TUESDAY AND WEDNESDAY. THIS SETUP IS NOT MUCH OF A
PRECIPITATION PRODUCER FOR OUR AREA WITH THE APPALACHIANS GENERALLY
RINGING OUT WHAT LITTLE AVAILABLE MOISTURE THERE IS. TEMPERATURE
FORECAST REMAINS MOST INTERESTING WITH LATEST MEX NUMBERS SHOWING
UPPER 30S ACROSS THE AREA. LATEST ENSEMBLE NUMBERS HAVE TRENDED
WARMER HOWEVER WITH THE OPERATIONAL NUMBERS THE COOLEST.
&&
.AVIATION /17Z THURSDAY THROUGH TUESDAY/...
AS OF 18Z...CURRENTLY MVFR CIGS AT KILM/KLBT...WHILE VFR PREVAILS AT
KFLO/KCRE/KMYR. ANTICIPATE BRIEF PERIODS OF MVFR/IFR ASSOCIATED
WITH EXPECTED SHOWERS AND THUNDERSTORMS LATE THIS AFTERNOON/EARLY
EVENING. EXPECT RAINFALL TO BECOME STEADY OVERNIGHT...WITH
CONDITIONS LIKELY DETERIORATING TO MVFR/IFR GIVEN ANTICIPATED STEADY
STATE OF RAINFALL AND LOWERED CIGS.
CURRENT VISIBLE SATELLITE IMAGERY ILLUSTRATES CLOUD COVER ASSOCIATED
WITH A COLD FRONT DRAPED NEARLY HORIZONTALLY ACROSS THE CAROLINA
BORDER GIVE OR TAKE. CONDITIONS WILL BE CONDUCIVE FOR ISOLATED
TO SCATTERED CONVECTION LATER AFTERNOON/EARLY EVENING...POSSIBLY
SEVERE AT KFLO/KCRE/KMYR WITH DAMAGING WINDS BEING THE PRIMARY
THREAT. FOR NOW...HAVE INTRODUCED VCTS AT THESE SITES GIVEN
UNCERTAINTY OF ONSET OF ACTIVITY. FOR KILM/KLBT...HAVE INTRODUCED
VCSH...BUT CANNOT RULE OUT A ROUGE THUNDERSTORM AS WELL IN NC. WINDS
WILL BE GENERALLY NORTH-NORTHEAST THROUGHOUT THE DAY...WITH
SUSTAINED WINDS AOB 12 KTS...AND GUSTS UP TO 25 KTS POSSIBLE.
OVERNIGHT...ANTICIPATE RAINFALL TO BECOME STEADY AND LAST THROUGH
THE REMAINDER OF THE VALID PERIOD. CIGS WILL LIKELY DIP TO NEAR 1500
FT...CREATING MVFR RESTRICTIONS. CANNOT RULE OUT POSSIBLE IFR
RESTRICTIONS DUE TO HEAVIER RAINFALL AND/OR LULLS IN ACTIVITY WHICH
MAY ALLOW FOG TO DEVELOP TEMPORARILY. NORTH WINDS EARLY ON FRIDAY
WILL GRADUALLY BECOME NORTHEAST...WITH WINDS IN THE MORNING AOB
10KTS AND GUSTS TO NEAR 20 KTS.
EXTENDED OUTLOOK...ISOLATED SHOWERS POSSIBLE MONDAY MORNING.
OTHERWISE EXPECT VFR THROUGH EXTENDED PERIOD.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 PM THURSDAY...FRONT HAS ADVANCED SOUTH THROUGH CAPE FEAR
AND IS ABOUT 10-15 MILES SOUTH OF THE BRUNSWICK COUNTY BEACHES. THIS
IS IN GOOD AGREEMENT WITH EARLIER PROJECTIONS. BASED ON A STRONGER-
THAN-EXPECTED SURGE OF NORTHEAST WINDS WE HAVE STARTED THE SMALL
CRAFT ADVISORY NORTH OF LITTLE RIVER INLET NOW RATHER THAN WAITING
UNTIL TONIGHT AS ORIGINALLY ADVERTISED. WIND GUSTS AT WRIGHTSVILLE
BEACH HAVE ALREADY REACHED 30 KNOTS AT TIMES. WIND SPEEDS SHOULD
DECREASE BY ABOUT 5 KNOTS BY LATE AFTERNOON...BUT WILL INCREASE
AGAIN TONIGHT. PREVIOUS DISCUSSION FROM 10 AM FOLLOWS..
A SOUTHWARD MOVING COLD FRONT WILL EVENTUALLY SWEEP ACROSS ALL OF
OUR MARINE AREA BY THIS EVENING. AT 10 AM THE FRONT WAS LOCATED NEAR
WRIGHTSVILLE BEACH AND EXTENDED OUT HUNDREDS OF MILES TO THE EAST.
SATELLITE SHOWS THE BOUNDARY SHOULD REACH THE BRUNSWICK COUNTY
BEACHES AROUND NOON...AND THE MYRTLE BEACH AROUND BETWEEN 1 AND 2
PM. A SURGE OF NORTHEAST WINDS TO AS STRONG AS 20 KNOTS IS EXPECTED
WHEN THE FRONT PASSES OVERHEAD. SHOWERS AND THUNDERSTORMS ARE
EXPECTED TO DEVELOP INLAND ALONG THE FRONT AND PUSH OFFSHORE THIS
AFTERNOON. THE LARGEST CONCENTRATION OF STORMS WILL PROBABLY BE IN
THE MYRTLE BEACH VICINITY...MAINLY AFTER 2 PM.
SPECTRAL WAVE DATA FROM THE FRYING PAN SHOALS BUOY SHOWS SEAS ARE
ALMOST EVENLY SPLIT BETWEEN A LONG 15-SECOND EASTERLY SWELL AND
SHORTER PERIOD WIND WAVES FROM THE WEST WINDS AHEAD OF THE FRONT.
THE SWELL WILL CONTINUE THROUGH TONIGHT...BUT AN INCREASING
NORTHEAST WIND CHOP WILL DEVELOP BEHIND THE FRONT LEADING TO OUR
CURRENT 2-3 FT SEAS TO INCREASE TO AS HIGH AS 4-5 FT BY SUNSET NORTH
OF CAPE FEAR. CONDITIONS WILL FURTHER DETERIORATE TONIGHT.
SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 3 AM THURSDAY...CONTINUED TO USE THE GFS WINDS WHICH ARE
STRONGER WHEN COMPARED TO THE NAM FOR THE PERIOD. THIS WARRANTS AN
EXTENDED PERIOD OF GUSTS TO GALE FORCE BEGINNING EASTERNMOST WATERS
THEN BLOSSOMING WESTWARD AS WE GO THROUGH THE DAY FRIDAY. HAVE
ISSUED A GALE WATCH FOR ALL WATERS FROM 1200 FRIDAY TO 0000 UTC
SATURDAY. SUSTAINED WINDS A COUPLE OF KNOTS EITHER SIDE OF 30 KNOTS
ARE EXPECTED. WINDS DIMINISH EARLY SATURDAY ALTHOUGH RESIDUAL HIGH
SEAS WILL WARRANT A SMALL CRAFT ADVISORY. ALL WATERS SHOULD BE FREE
OF ANY HEADLINES LATER SATURDAY AFTERNOON.
LONG TERM /SUNDAY THROUGH MONDAY/...
AS OF 3 AM THURSDAY...BENIGN WINDS SUNDAY...TEN KNOTS OR LESS WILL
INCREASE MONDAY AS A COLD FRONT MOVES ACROSS THE WATERS. NORTHWEST
WINDS OF 10-15 KNOTS WILL DEVELOP. SEAS OF 2-3 FEET INITIALLY WILL
INCREASE ONLY SLIGHTLY TO 2-4 FEET MONDAY WITH THE FOUR FOOTERS WELL
OFFSHORE WITH THE FETCH.
&&
.TIDES/COASTAL FLOODING...
THE FULL MOON IS UPON US AND WITH THE DEVELOPING AND INCREASING NE
WINDS AND HEAVY RAINFALL...THERE IS A RISK FOR SOME MINOR COASTAL
FLOODING. DOWNTOWN WILMINGTON WILL LIKELY EXPERIENCE MINOR FLOODING
ALONG THE CAPE FEAR THIS EVE AND AGAIN FRI EVE AS THE GAGE READING
EXCEEDS 5.5 FT AT HIGH TIDE. ALONG THE COAST...MINOR COASTAL
FLOODING IS POSSIBLE AT HIGH TIDE ON FRI. THE HIGHEST OF THE TWO
PREDICTED HIGH TIDES IS DURING THE EVE. HOWEVER...THE HEAVY RAIN FRI
MORNING MAY ALLOW FOR A PERIOD OF MINOR COASTAL FLOODING AT THAT
TIME AS WELL. HIGH TIDES ALONG THE COAST...7P TONIGHT AND ON FRI...
730A AND 8P. THE HIGHEST WATER LEVELS IN DOWNTOWN WILMINGTON OCCUR 2
TO 3 HOURS AFTER HIGH TIDE AT THE BEACHES.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...COASTAL FLOOD ADVISORY FOR NEW HANOVER COUNTY 8-11 PM TONIGHT.
MARINE...GALE WATCH FROM FRIDAY MORNING THROUGH FRIDAY EVENING FOR
AMZ250-252-254-256.
SMALL CRAFT ADVISORY FROM 2 AM TO 8 AM EDT FRIDAY FOR AMZ250-
252-254-256.
&&
$$
NEAR TERM...TRA
SHORT TERM...SHK
LONG TERM...SHK
AVIATION...SGL
TIDES/COASTAL FLOODING...RJD
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
335 PM CDT THU APR 5 2012
.SHORT TERM...
.TONIGHT AND THURSDAY...FORECAST CONFIDENCE HIGH.
MIN TEMPS STILL EXPECTED TO BE IN THE UPPER 20S TO LOW 30S RANGE
OVERNIGHT. THEREFORE...FREEZE WARNING FOR ENTIRE FORECAST AREA.
LOCATIONS RIGHT ALONG THE LAKE ARE NOT EXPECTED TO DROP BELOW
FREEZING. 925MB TEMPS WILL DROP TO AROUND 1C TONIGHT. WITH A
MODERATE TO WEAK INVERSION...MIN TEMPS SHOULD BE IN THE 27 TO 30
DEGREE RANGE. NAM...ECMWF AND GEM MODELS SHOW THE COLDEST TEMPS
TONIGHT. OTHER MODELS STRUGGLE TO DROP THE TEMPS BELOW 30 DEGREES
WELL INLAND FROM THE LAKE.
THE COLDEST CORE OF THE 850MB TEMPS MOVE ACROSS SOUTHEAST WI DURING
THE NIGHT AND THEN WARM SLIGHTLY TOWARD MORNING. WEAKEST PRESSURE
GRADIENT WILL NOT MOVE OVERHEAD UNTIL AFTER 9Z. WITH LAKE TEMPS
AROUND 43F/6C AND 850MB TEMPS AROUND -2C...THE 8C LAKE-AIR
DIFFERENCE COULD BE ENOUGH TO GENERATE SOME LAKE CLOUDS IN SOUTHEAST
WI. RUC SHOWS THEM OVER THAT AREA BETWEEN 4Z AND 10Z. 1000-850MB RH
PLOTS SHOW THE AREA OF HIGHER RH SHIFTING INLAND AND DRYING OUT
TOWARD FRI MORNING. THE RUC DOES LOOK OVERDONE IN ITS INITIALIZATION
THIS AFTERNOON...SO THIS IS A LOW-CONFIDENCE SCENARIO. THE NAM AND
GFS ALSO HINT AT THE LAKE CLOUD POSSIBILITY...BUT DO NOT SEEM OVERLY
EXCITED. ANY STRATUS DEVELOPMENT WOULD INHIBIT TEMPS FROM GETTING
BELOW FREEZING.
GRADIENT OF COLDER 925 MB TEMPERATURES SETTLING INTO THE EAST WITH
WARMER READINGS THROUGH MIDDAY FRIDAY WEST YIELDS HIGHS IN THE MID
AND UPPER 50S IN THE WESTERN 2/3 OF FORECAST AREA...WITH MID TO
UPPER 40S IN THE EAST.
.SATURDAY AND SATURDAY NIGHT...FORECAST CONFIDENCE...HIGH
A MID/UPPER LEVEL RIDGE OVER THE WESTERN GREAT LAKES SATURDAY
PUSHES EAST INTO THE EASTERN GREAT LAKES SATURDAY NIGHT AS A
SHORTWAVE EXITS THE NORTHERN PLAINS THAT REACHES NORTHWEST
WISCONSIN SATURDAY EVENING.
THE SHORTWAVE PRODUCES A STRONG LOW OVER CENTRAL CANADA AS A
TRAILING COLD FRONT ENTERS SOUTH CENTRAL WISCONSIN LATE SATURDAY
AFTERNOON AND EXITS THE SOUTHEAST SATURDAY NIGHT.
NAM FORECAST SOUNDINGS SHOW A RATHER SUBSTANTIAL CAP AROUND 7 THSD
FT WITH THE CAP WEAKENING SATURDAY EVENING AS SATURATION OCCURS
MAINLY BETWEEN 6 AND 12 THSD FT. ELEVATED CAPE IS MINIMAL SO WILL
GO WITH JUST A BAND OF SHOWERS FOLLOWED BY RATHER STRONG COLD AIR ADVECTION.
PRESSURE GRADIENT SHOULD INHIBIT FROST POTENTIAL SOMEWHAT DUE TO
WIND. WILL CONTINUE TO MENTION A POSSIBILITY. TEMPERATURES WILL
DROP INTO THE 30S BUT FREEZING TEMPERATURE POTENTIAL IS MINIMAL.
.SUNDAY AND MONDAY...FORECAST CONFIDENCE...HIGH
MAIN UPPER TROUGH BEGINS TO DIG ACROSS THE GREAT LAKES AND
NORTHEAST U.S. WEST/NORTHWEST MID/UPPER LEVEL FLOW BECOMES MORE
NORTHWEST ON MONDAY. DUE TO THE COLD AIR ALOFT AND CYCLONIC FLOW
EXPECT SOME STRATOCUMULUS...ESPECIALLY DURING THE DAYTIME AS THE MAIN
SURFACE HIGH EXTENDS ACROSS CENTRAL CANADA AND INTO THE PLAINS.
TEMPERATURES WILL COOL BACK TOWARD NORMAL BY MONDAY.
.LONG TERM...
.TUESDAY AND WEDNESDAY...FORECAST CONFIDENCE...HIGH
THE 12Z GFS/00Z ECMWF KEEP THE NORTHWEST MID/UPPER FLOW AS AN
UPPER RIDGE BUILDS ACROSS THE EASTERN PLAINS INTO MINNESOTA.
THE SURFACE HIGH EXTENDS ACROSS THE UPPER MISSISSIPPI VALLEY AND
WESTERN GREAT LAKES.
TEMPERATURES WILL BE COOL AND A FROST/FREEZE POTENTIAL WILL EXIST.
.THURSDAY...FORECAST CONFIDENCE...MEDIUM
A SHORTWAVE PUSHES ACROSS THE CENTRAL ROCKIES WITH THE MID/UPPER
RIDGE NEAR THE EASTERN HIGH PLAINS AND MISSISSIPPI VALLEY.
THE SURFACE HIGH BECOMES CENTERED OVER THE GREAT LAKES AS A TROUGH
OF LOW PRESSURE ORGANIZES OVER THE CENTRAL HIGH PLAINS. THE
PRECIPITATION FROM THIS SYSTEM SHOULD REMAIN TO THE WEST.
&&
.AVIATION/00Z TAFS/...
HIGH PRESSURE SINKING SOUTHWARD ACROSS WI OVERNIGHT WILL BRING
DECREASING WINDS TOWARD FRI MORNING. CLEAR SKIES EXPECTED...BUT IT
SHOULD BE MENTIONED THAT THERE IS A THREAT FOR LAKE-INDUCED MVFR
CLOUDS TO DEVELOP ONCE AGAIN OVERNIGHT AT THE EASTERN TAF
SITES...THEN DISSIPATE FRI MORNING AS THE WEAKER WINDS AND DRIER AIR
MOVE OVERHEAD. MOST PROBABLY TIME PERIOD IF THEY WERE TO DEVELOP
WOULD BE 04Z TO 10Z.
CLEAR SKIES AND LIGHT WINDS ON FRIDAY.
&&
.MARINE...
SMALL CRAFT ADVISORY REMAINS IN EFFECT THROUGH OVERNIGHT TONIGHT.
SUSTAINED NORTHEAST WINDS OF 15 TO 25 KNOTS DUE TO THE TIGHT
PRESSURE GRADIENT BETWEEN HIGH PRESSURE TO THE NORTH AND LOW
PRESSURE TO THE SOUTH. WINDS WILL BEGIN TO EASE EARLY THIS EVENING
AS GRADIENT RELAXES WITH CORE OF HIGH SETTLING DOWN INTO EASTERN
WISCONSIN BY 12Z FRIDAY... BUT WAVES WILL REMAIN HIGH UNTIL THE
MID-OVERNIGHT HOURS.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...FREEZE WARNING FROM LATE TONIGHT THROUGH FRIDAY MORNING FOR
WIZ046-047-051-052-056>060-062>072.
LM...SMALL CRAFT ADVISORY UNTIL 4 AM CDT FRIDAY FOR LMZ643>646.
&&
$$
TONIGHT/FRIDAY AND AVIATION/MARINE...MRC/MEB
FRIDAY NIGHT THROUGH THURSDAY...HENTZ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
325 PM CDT THU APR 5 2012
.SHORT TERM...TODAY THROUGH SUNDAY
325 PM CDT THU APR 5 2012
FORECAST CONCERNS INCLUDE FREEZE POTENTIAL FOR LATE TONIGHT/EARLY
FRIDAY MORNING...RAIN CHANCES SATURDAY/SATURDAY EVENING.
CURRENT LOOP OF WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW HIGHLY
AMPLIFIED RIDGE OF HIGH PRESSURE EXTENDING FROM THE PLAINS INTO
WESTERN ONTARIO/HUDSON BAY CANADA. AT THE SURFACE...HIGH PRESSURE
WAS CENTERED OVER WESTERN HUDSON BAY WITH DRY/COOL NORTHEAST FLOW
SET UP INTO WESTERN GREAT LAKES/UPPER MISSISSIPPI RIVER REGIONS.
TEMPERATURES WERE IN THE 50S WITH RELATIVE HUMIDITIES READINGS IN
THE 25-30 PERCENT RANGE.
05.12Z NCEP MODEL SUITE AS WELL AS THE GEM/ECMWF ALL IN GOOD
AGREEMENT THROUGH THE SHORT TERM PERIOD.
FOR TONIGHT...WILL SEE THE HIGH OVER HUDSON BAY SINK SLOWLY SOUTH
TOWARD LAKE SUPERIOR BY MORNING WITH THE RIDGE AXIS SETTING UP
PRETTY MUCH SQUARE OVER THE AREA. THIS WILL ALLOW FOR RAPID
DECOUPLING OF THE LOWER BOUNDARY LAYER CAUSING WINDS TO BE VERY
LIGHT TO CALM. CLEAR SKIES WILL ALSO ALLOW FOR GOOD RADIATIONAL
COOLING WITH TEMPERATURES BOTTOMING OUT IN THE 25 TO 30 DEGREE RANGE
EAST OF THE MISSISSIPPI RIVER. WEST OF THE RIVER...WINDS MAY NOT
DECOUPLE ALL THE WAY AND THIS MAY BE ENOUGH TO KEEP SOME LIGHT
STIRRING GOING TO KEEP TEMPERATURES UP AROUND 32 DEGREES.
STILL...THERE WILL LIKELY BE POCKETS OF COLDER TEMPERATURES WHERE
WINDS DO DECOUPLE. WITH THIS IN MIND...AND COLLABORATION WITH OTHER
OFFICES...WILL GO WITH A FREEZE WARNING FOR THE ENTIRE AREA FROM 2 AM
TO 8 AM.
LOOK FOR THE CENTER OF THE HIGH TO SLIP EAST INTO LOWER MI ON
FRIDAY. AT THE SAME TIME...A DEEP AREA OF LOW PRESSURE MOVES OUT OF
THE INTERMOUNTAIN WEST TO ALONG THE MT/DAKOTA BORDER. THIS WILL SET
U INCREASING SOUTHEAST FLOW ACROSS THE AREA...ESPECIALLY ACROSS THE
HIGHER/MORE WIND-PRONE AREAS OF SOUTHEAST MN/NORTHEAST IA. LOOKING
FOR SOUTHEAST WINDS IN THE 5 TO 10 MPH RANGE EAST OF THE MISSISSIPPI
AND 10-20 MPH ACROSS THE AFOREMENTIONED FAVORED WIND AREAS. ALSO ON
FRIDAY...925-850MB TEMPERATURES INCREASE INTO THE 4-6C RANGE. THIS
SHOULD RESULT IN HIGHS TOPPING OFF IN THE UPPER 50S TO LOWER 60S.
WE WILL STILL SEE DRY OUTFLOW FROM THE HIGHS WITH DEW POINTS IN THE
UPPER TEENS TO MIDDLE 20S. THIS COULD RESULT IN INCREASED FIRE
WEATHER CONCERNS. MORE DETAIL CAN BE FOUND BELOW IN THE FIRE WEATHER
SECTION.
NEXT ON THE DOCKET WILL BE INCOMING COLD FRONT FOR SATURDAY. MODELS
SHOWING DIMINISHING 850-925MB MOISTURE TRANSPORT INTO THE AREA AS
THE FRONT MOVES INTO THE AREA BY AFTERNOON. AS A RESULT...NIL TO
MINIMAL MUCAPE WAS NOTED BY THE NAM/GFS. BASED ON THIS SIGNAL...HAVE
PULLED ANY THUNDER MENTION. BOTTOM LINE RESULT WITH THIS FRONTAL
PASSAGE WILL BE THE LIKELIHOOD OF A SCATTERED TO BROKEN LINE OF
SHOWERS WITH MINIMAL RAINFALL OF A FEW HUNDRETHS OF AN INCH OR SO.
WILL MAINTAIN A 40-50 POP FOR NOW BASED ON THIS REASONING. APPEARS
FRONT AND RAIN CHANCES WILL EXIT EAST OF THE AREA BY MIDNIGHT.
ON SUNDAY...MODELS SHOW THE AREA IN BREEZY WESTERLY FLOW IN THE WAKE
OF THE COLD FRONT AND LOW PASSING THROUGH SOUTHERN ONTARIO CANADA.
WINDS LIKELY TO BE IN THE 15 TO 25 MPH RANGE WITH GUSTS IN THE 30-40
MPH POSSIBLE IF FULL MIXING CAN BE REALIZED. SCATTERED TO BROKEN
FIELD OF CUMULUS/STRATOCUMULUS ALSO EXPECTED WITH COOLER CYCLONIC
FLOW ALOFT. CLOUDS LOOKS LIKE THEY WILL BE MOST PREVALENT NORTH OF
I-90 AND EAST OF THE MISSISSIPPI RIVER WHERE STEEPER LOW LEVEL LAPSE
RATES WILL RESIDE. OTHERWISE...TEMPERATURES WILL BE A BIT COOLER IN
THE LOW TO MID 50S.
.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY
325 PM CDT THU APR 5 2012
05.12Z GFS/ECMWF IN GENERALLY GOOD AGREEMENT THROUGH THE LONG TERM.
BOTH SHOW A COOLING/DRY TREND THROUGH TUESDAY...AS COLD CANADIAN
HIGH PRESSURE OOZES INTO THE REGION. LOOKING AT HIGHS IN THE 40S TO
LOWER 50S WITH OVERNIGHT LOWS MONDAY/TUESDAY NIGHTS IN THE UPPER 20S
TO LOWER 30S FOR ANOTHER ROUND OF FREEZE POTENTIAL. WILL KEEP A
CLOSE EYE ON THIS OVER THE NEXT FEW DAYS. SOME MODEST WARMING THEN
EXPECTED WEDNESDAY AND THURSDAY AS THE SURFACE RIDGE MOVES EAST AND
HEIGHT BUILD ALOFT. LOOKING FOR HIGHS IN THE 50-55 DEGREE RANGE
WEDNESDAY AND MID 50S THURSDAY.
&&
.AVIATION...THROUGH 18Z FRIDAY
1150 AM CDT THU APR 5 2012
QUIET 24 HOURS AT THE TAF SITES WITH WIND THE ONLY CONCERN WITH A
RIDGE OF HIGH PRESSURE PUSHING SOUTH FROM ONTARIO. OUTSIDE OF SOME
HIGH LEVEL CIRRUS THIS AFTERNOON...SKIES WILL BE CLEAR OVERNIGHT
INTO FRIDAY MORNING. WINDS WILL START OUT OF THE EAST TODAY BEFORE
VEERING TO THE SOUTHEAST FRIDAY MORNING. WIND SPEEDS WILL
GENERALLY BE IN THE 9 TO 12 KT RANGE THIS AFTERNOON WITH A FEW
GUSTS BRIEFLY IN THE 16 TO 18 KT RANGE. WINDS WILL GO LIGHT
TONIGHT BEFORE PICKING BACK UP FRIDAY MORNING.
&&
.FIRE WEATHER...THROUGH FRIDAY
325 PM CDT THU APR 5 2012
ONE MORE DAY OF LOW RELATIVE VALUES EXPECTED ON FRIDAY. LOOK FOR
MINIMUM RH VALUES IN THE 20-25 PERCENT RANGE WITH DRY SOUTHEAST
OUTFLOW FROM HIGH PRESSURE SLIDING INTO THE GREAT LAKES REGION.
SOUTHEAST WINDS EXPECTED TO BE IN THE 7-12 MPH RANGE EAST OF THE
MISSISSIPPI RIVER AND IN THE 10-20 MPH RANGE OVER THE HIGHER/MORE
WIND-PRONE AREAS OF SOUTHEAST MN/NORTHEAST IA.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
325 PM CDT THU APR 5 2012
WI...FREEZE WARNING FROM 2 AM TO 8 AM CDT FRIDAY FOR WIZ017-029-
032>034-041>044-053>055-061.
MN...FREEZE WARNING FROM 2 AM TO 8 AM CDT FRIDAY FOR MNZ079-086>088-
094>096.
IA...FREEZE WARNING FROM 2 AM TO 8 AM CDT FRIDAY FOR IAZ008>011-018-
019-029-030.
&&
$$
SHORT TERM...DAS
LONG TERM...DAS
AVIATION...HALBACH
FIRE WEATHER...DAS
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
243 PM CDT THU APR 5 2012
.SHORT TERM...TONIGHT AND FRIDAY.
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A HUDSON BAY
HIGH ANCHORED OVER NORTHERN ONTARIO THIS AFTERNOON WHILE LOW
PRESSURE RESIDES OVER THE SOUTHERN OHIO VALLEY. LAKE EFFECT CLOUDS
DEVELOPED EARLIER TODAY AND CREATED A FEW HOUR PERIOD OF BKN
CONDITIONS OVER NORTHEAST WISCONSIN. BUT OVER-LAKE INSTABILITY HAS
WANED SINCE THEN AND CLOUDS HAVE DISSIPATED. MOSTLY SUNNY
CONDITIONS NOW EXIST OVER THE ENTIRE AREA THOUGH TEMPERATURES ARE
STRUGGLING TO GET OUT OF THE 40S. AS HIGH PRESSURE BUILDS SOUTH
TONIGHT...FREEZE HEADLINES ARE THE FORECAST CONCERN OVER THE NEXT 24
HOURS.
TONIGHT...HUDSON BAY HIGH PRESSURE OVER ONTARIO WILL SINK TO THE
SOUTH TONIGHT AND SETTLE OVER THE NORTHERN GREAT LAKES BY MORNING.
BEFORE THIS OCCURS...0-1KM AGL FLOW WILL BE 15-20KTS OVER
EAST-CENTRAL AND NORTHEAST WISCONSIN THROUGH THE EVENING SO
TEMPERATURES MAY STRUGGLE TO FALL OFF INITIALLY. BUT AS THE HIGH
PRESSURE ARRIVES AFTER MIDNIGHT...THE PRESSURE GRADIENT SLACKENS AND
BL WINDS BECOME 5KTS OR LESS BY 09Z ACROSS THE ENTIRE AREA.
MANITOWOC AND STURGEON BAY FELL TO 32 AND 30 DEGREES RESPECTIVELY
LAST NIGHT...AND WILL BE OFF TO A COLDER START THIS EVENING THAN
LAST EVENING. WITH LIGHTER WINDS TONIGHT...TEMPS DO NOT HAVE MUCH
TO FALL FOR AREAS IN THE FREEZE WATCH TO REACH FREEZE WARNING
CRITERIA (TEMP OF 28F). SO WILL UPGRADE THE FREEZE WATCH TO A
FREEZE WARNING. LOWS RANGING FROM THE UPPER TEENS TO LOWER 20S AT
THE COLD SPOTS...TO AROUND 30F NEAR THE LAKE MICHIGAN SHORELINE.
FRIDAY...HIGH PRESSURE WILL BE CENTERED OVER THE CENTRAL GREAT LAKES
FOR FRIDAY. WITH SUNNY SKIES...LOW LEVEL TEMPERATURES WILL MODERATE
BY SEVERAL DEGREES COMPARED TO TODAY. 925MB TEMPS OF 8C OVER
CENTRAL WISCONSIN AND 4C OVER EASTERN WISCONSIN CALLS FOR HIGHS IN
THE UPPER 50S WEST TO AROUND 50 DEGREES EAST.
.LONG TERM...FRIDAY NIGHT THROUGH NEXT THURSDAY...MAIN FCST CONCERNS
ARE LINGERING FROST/FREEZE POTENTIAL FRIDAY NIGHT...THEN PCPN TRENDS
SATURDAY AFTERNOON AND NIGHT.
A HUDSON BAY HIGH WILL BE EDGING EASTWARD ON FRIDAY NIGHT...BUT
LINGERING DRY AIR...MOSTLY CLEAR SKIES AND DECOUPLED WINDS WILL LIKELY
LEAD TO ANOTHER NIGHT OF FROST/FREEZE CONDITIONS. THE BEST CHANCE FOR
A HARD FREEZE WILL BE ACROSS NC/FAR NE WI...WHERE MIN TEMPS SHOULD
DROP INTO THE MID TO UPPER 20S.
A COLD FRONT WILL AFFECT THE REGION LATE SATURDAY INTO SATURDAY NIGHT.
MODELS ARE FAIRLY CONSISTENT WITH PCPN TRENDS...AND SUGGEST THAT SHOWERS
WILL MAKE IT ACROSS THE WESTERN HALF OF THE FORECAST AREA LATE SATURDAY
AFTERNOON...AND ACROSS THE REST OF GRB CWA SATURDAY EVENING. HAVE RAISED
POPS TO LIKELY IN OUR FAR WESTERN COUNTIES ON SAT AFTERNOON...AND ACROSS
THE REMAINDER OF THE CWA SATURDAY EVG. STABILITY INDICES ARE UNIMPRESSIVE...
AND AFTER COORD WITH SURROUNDING OFFICES...HAVE OPTED TO REMOVE ANY
MENTION OF THUNDER WITH THIS SYSTEM.
SUNDAY SHOULD BE MAINLY DRY...ALTHOUGH AN INCREASE IN CLOUDS IS EXPECTED
IN OUR NW COUNTIES DURING THE AFTERNOON AS A WEAKENING UPPER LOW MOVES
TOWARD THE REGION. THIS SYSTEM SHOULD BRING A SMALL CHANCE OF SHOWERS
ON SUNDAY NIGHT AND MONDAY...ESPECIALLY ACROSS NC/NE WI. COOL NORTH
FLOW WILL BRING MOSTLY CLOUDY SKIES TO NORTHERN WI MONDAY NIGHT AND
TUESDAY. MAX TEMPS WILL BE BELOW NORMAL DURING THIS PERIOD.
AN UPPER LEVEL RIDGE WILL GRADUALLY BUILD INTO THE REGION FROM THE
NORTHERN PLAINS LATER IN THE WEEK...RESULTING IN PLENTY OF SUNSHINE
AND A GRADUAL MODERATION IN TEMPERATURES.
&&
.AVIATION...PATCHY MVFR CIGS OVER EAST-CENTRAL WISCONSIN WILL
DISSOLVE EARLY THIS AFTERNOON...LEAVING VFR CONDITIONS THROUGH
THE REST OF THE TAF PERIOD. WIDESPREAD FROST SHOULD BE PRESENT
ACROSS MUCH OF THE AREA EARLY TOMORROW MORNING.
MPC
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
FREEZE WARNING FROM 2 AM TO 8 AM CDT FRIDAY FOR WIZ005-010>013-
018>022-030-031-035>040-045-048>050-073-074.
&&
$$
MPC/KIECKBUSCH