Forecast Discussions mentioning any of
"HRRR" "RR" "RUC13" "RUC" received at GSD on 03/07/12
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
938 AM EST MON MAR 5 2012
.UPDATE...WELL-DEFINED SFC COLD FRONT VIA RUC THICKNESS FIELD
MOVING THROUGH S CENTRAL GA AND SRN SC WITH SFC LOW PRES OVER WRN
VA...MOVING E TO SE. OUR LOCAL FLOW IS WLY AND CONTS TO INCREASE
AHEAD OF THE DRY COLD FRONT. THE FRONT WILL PUSH THROUGH OUR AREA
DURING THE DAY WITH LLVL FLOW TURNING TO THE NW OVER NRN ZONES
AFTER 18Z. JAX 12Z SOUNDING SHOWS VERY DRY AIR WITH PWAT OF 0.27
INCHES AND WARM CONDS ALOFT...AND ABLE TO SUPPORT HIGHS IN THE
LOWER TO MID 70S OVER THE SRN HALF OF THE ZONES...WITH NEAR 70
OVER THE N ZONES DUE TO COLD FRONTAL PASSAGE. THESE TEMPS AFTER A
COOL MORNING WITH LOWS OF 32-35 OVER INLAND NE FL WHERE FROST WAS
NOTED EARLY THIS MORNING...WITH UPPER 30S AND LOWER 40S IN SE GA.
LOOKING AT WIND POTENTIAL...APPEARS WE SHOULD MIX UP TO ABOUT
4000-5500 FT TODAY TAPPING INTO THE 850 MB WINDS OF 30-45 MPH
AND THUS WE ARE LOOKING FOR GUSTS ROUGHLY IN THAT RANGE...
MAINLY OVER THE NRN 2/3RDS OF THE FORECAST AREA. WIND AND LAKE WIND
ADVISORIES LOOK GOOD ATTM.
&&
.AVIATION...VFR. WINDS WILL PICK UP TO 15-20G25KT...EXCEPT GNV
WHERE SLIGHTLY WEAKER WINDS OF 10-15G20KT ARE EXPECTED.
&&
.MARINE...WINDS HAVE PICKED UP TO A LITTLE SOONER THAN MODELS
PREDICTED. SCA IS UP FOR OFFSHORE GA WATERS WITH SCEC FOR OTHER
MARINE ZONES. BASED ON 41008 AT 23G27KT WILL PUT REST OF GA WATERS
IN SCA. WINDS AT 41012 ALREADY UP TO 17G21KT AND SEAS NEAR 4 FT.
OTHERWISE...FCST ON TRACK.
RIP CURRENTS: LOW TODAY AND INCREASING TO SOLID MODERATE ON TUE.
BUILDING OF SURF OF TUE-FRI WILL ENHANCE RIP CURRENTS PROBABLY
INTO HIGH RISK CATEGORY.
&&
.FIRE WEATHER...RED FLAG WARNING CONDITIONS EXPECTED TODAY WITH
DRY W TO NW FLOW AND WARMING TEMPS. MIN RH VALUES IN THE 20S
EXPECTED WITH GUSTY WINDS AROUND 15-20 MPH WITH GUSTS AROUND 25-40
MPH.
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...RED FLAG WARNING UNTIL 6 PM EST THIS EVENING FOR ALACHUA-BAKER-
BRADFORD-CLAY-COLUMBIA-DUVAL-FLAGLER-GILCHRIST-HAMILTON-
MARION-NASSAU-PUTNAM-ST JOHNS-SUWANNEE-UNION.
LAKE WIND ADVISORY UNTIL 6 PM EST THIS EVENING FOR BAKER-
BRADFORD-CLAY-COLUMBIA-DUVAL-HAMILTON-NASSAU-ST JOHNS-
SUWANNEE-UNION.
GA...RED FLAG WARNING UNTIL 6 PM EST THIS EVENING FOR APPLING-
ATKINSON-BACON-BRANTLEY-CHARLTON-CLINCH-COASTAL CAMDEN-
COASTAL GLYNN-COFFEE-ECHOLS-INLAND CAMDEN-INLAND GLYNN-JEFF
DAVIS-PIERCE-WARE-WAYNE.
WIND ADVISORY UNTIL 6 PM EST THIS EVENING FOR APPLING-BACON-
BRANTLEY-COASTAL CAMDEN-COASTAL GLYNN-INLAND CAMDEN-INLAND
GLYNN-JEFF DAVIS-PIERCE-WAYNE.
LAKE WIND ADVISORY UNTIL 6 PM EST THIS EVENING FOR ATKINSON-
CHARLTON-CLINCH-COFFEE-ECHOLS-WARE.
AM...SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 6 PM EST FRIDAY
FOR FERNANDINA BEACH TO ST AUGUSTINE FL 20 NM TO 60 NM
OFFSHORE-ST AUGUSTINE TO FLAGLER BEACH FL 20 NM TO 60 NM
OFFSHORE.
SMALL CRAFT ADVISORY UNTIL 6 PM EST FRIDAY FOR ALTAMAHA SOUND GA
TO FERNANDINA BEACH FL 20 NM TO 60 NM OFFSHORE.
SMALL CRAFT ADVISORY FOR WINDS UNTIL 7 PM EST THIS EVENING FOR
ALTAMAHA SOUND GA TO FERNANDINA BEACH FL OUT 20 NM.
&&
$$
SHASHY/WALKER
AREA FORECAST DISCUSSION
NWS LINCOLN IL
219 PM CST MON MAR 5 2012
.DISCUSSION...
ISSUED 200 PM CST MON MAR 5 2012
SHORT TERM...TONIGHT THROUGH THURSDAY NIGHT
A STRONG SOUTH WIND TO BRING UNSEASONABLY WARM WEATHER BACK TO
CENTRAL...EAST CENTRAL AND SOUTHEAST ILLINOIS TUESDAY AND WEDNESDAY.
HIGH PRESSURE WILL CONTINUE TO SHIFT AWAY FROM CENTRAL IL TONIGHT
ALLOWING SOUTH WINDS TO INCREASE ACRS THE FORECAST AREA. THIS SHOULD
ALLOW FOR MORE OF AN EARLY EVENING LOW TEMPERATURE TO OCCUR BEFORE
READINGS BECOME STEADY OR SLOWLY RISE OVERNIGHT. THE NEXT SIGNIFICANT
UPPER LEVEL TROF WILL SETTLE INTO THE ROCKIES EARLY TUESDAY WITH
STRONG LOW PRESSURE EXPECTED TO PUSH ACROSS THE NORTHERN PLAINS. THE
TIGHTENING PRESSURE GRADIENT BETWEEN THE DEPARTING HIGH TO OUR EAST
AND THE NORTHERN PLAINS LOW WILL PRODUCE STRONG SOUTH WINDS OVER MOST
OF THE FORECAST AREA. 850 TEMPERATURES ARE FORECAST TO RISE FROM THIS
MORNINGS READING OF -10C TO +8 DEGREES C BY TUESDAY AFTERNOON...WHICH
SHOULD PUSH AFTERNOON TEMPERATURES TO AROUND 60 FAR EAST TO WITHIN A
FEW DEGREES OF 70 FAR WEST. FORECAST SOUNDINGS SUGGEST WE SHOULD BE
ABLE TO MIX DOWN FROM AROUND 4000 FEET WHERE WINDS ARE PROJECTED TO
BE IN THE 35 TO 45 MPH RANGE.
WINDS SHOULD DECREASE JUST A BIT TUESDAY NIGHT...ESPECIALLY WITH
THE GUSTS...BEFORE RAMPING UP AGAIN ON WEDNESDAY AS A FRONTAL BOUNDARY
APPROACHES FROM THE WEST. LOW LEVEL MOISTURE EXPECTED TO INCREASE DURING
THE DAY WITH CLOUDS INCREASING FROM SOUTH TO NORTH DURING THE DAY...ESP
ACRS THE WESTERN HALF OF THE FORECAST AREA. PRECIP CHANCES HAVE BEEN
PULLED BACK TO THE AFTERNOON...AND MOSTLY ACRS THE WEST AS IT APPEARS
THE BETTER MID LEVEL LAPSE RATES AND 700-500MB FORCING WILL BE ALONG
AND BEHIND THE FRONTAL BOUNDARY. OUR BEST CHANCE FOR MORE WIDESPREAD
SHOWERS AND THUNDERSTORMS WILL BE WEDNESDAY NIGHT AND THURSDAY AS THE
FRONT SLOWLY DRIFTS SE ACRS THE FORECAST AREA. DUE TO THE PROXIMITY
OF THE FRONTAL BOUNDARY TO OUR SOUTH THURSDAY NIGHT...WILL CONTINUE
WITH RAIN CHANCES...WITH THE HIGHEST POPS OVER THE SOUTH WHICH WILL
BE CLOSER TO THE FRONTAL BOUNDARY...WITH MAINLY SLIGHT CHANCE POPS
NORTH OF I-72.
LONG TERM...FRIDAY THROUGH MONDAY
THE COLD FRONT SHOULD CONTINUE TO PUSH SOUTH OF THE AREA ON FRIDAY
ALLOWING HIGH PRESSURE TO BUILD INTO THE REGION FOR A FEW DAYS BEFORE
WE TURN OUR ATTENTION TO THE CLOSED UPPER LOW ACRS THE SOUTHWEST U.S.
STILL SEEING SOME SPREAD WITH THE ENSEMBLES WITH RESPECT TO THE CLOSED
LOW ACRS THE SOUTHWEST OVER THE WEEKEND BUT NOT AS BAD AS WHAT WE
SAW OVER THE WEEKEND. MODELS HAVE SLOWED THE NE MOVEMENT OF THE UPPER
LOW AND ITS ASSOCIATED PRECIP SHIELD AND WITH NO APPARENT UPSTREAM KICKER
IN THE SOUTHERN STREAM...FEEL THE SLOWEST SOLUTIONS DEPICTED BY THE
CANADIAN AND UK MODELS MAY BE THE WAY TO GO. IF THE UK MODEL IS CLOSER
TO THE TRUTH...WE WON`T SEE ANY RAIN IN HERE UNTIL LATER SUNDAY/MONDAY.
HOWEVER...WITH THE MODELS STILL SHOWING SOME INCONSISTENCIES WITH
RESPECT TO THE EJECTION OF THE UPPER WAVE OUT OF THE SOUTHWEST U.S...WILL
HOLD OFF FROM MAKING ANY SIGNIFICANT CHANGES THIS FAR OUT IN THE FORECAST
PERIOD. ONE THING IS FOR SURE...THE UNSEASONABLY MILD WEATHER WILL PREVAIL
THRU THIS FORECAST PERIOD AS MEDIUM RANGE MODELS CONTINUE TO INDICATE
THE POLAR JET STREAM TO HOLD WELL TO OUR NORTH INTO AT LEAST THE MIDDLE
OF THE MONTH.
SMITH
&&
.AVIATION...
ISSUED 1112 AM CST MON MAR 5 2012
DIURNAL CUMULUS DEVELOPMENT DROPPED CEILINGS AS LOW AS 900 FEET
EARLIER THIS MORNING AT KCMI...BUT RECENT OBSERVATIONS ARE MORE
AROUND 2000-2500 FEET. RUC CU-RULE GUIDANCE SHOWING SCATTERED
CLOUDS CONTINUING ACROSS EAST CENTRAL ILLINOIS THROUGH MID
AFTERNOON...AND THESE SHOULD RISE INTO VFR RANGE THROUGH EARLY
AFTERNOON.
MAIN CONCERN AT THE TAF SITES IS WITH WINDS...BOTH SURFACE AND
ALOFT. PRESSURE GRADIENT WILL TIGHTEN UP THIS EVENING AS A STORM
SYSTEM MOVES ACROSS THE PLAINS. SHOULD SEE SURFACE GUSTS TO AROUND
20-25 KNOTS BY 06Z AT ALL SITES. FORECAST SOUNDINGS STILL SHOWING
LLWS DEVELOPING AROUND 1500 FEET BY 06Z. FULL SUNSHINE ON TUESDAY
SHOULD MIX DOWN THESE HIGH WINDS EASILY...AND HAVE BROUGHT GUSTS
UP TO AROUND 30 KNOTS OR SO BY THE END OF THE FORECAST PERIOD.
GEELHART
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1113 AM CST MON MAR 5 2012
.DISCUSSION...
ISSUED 1012 AM CST MON MAR 5 2012
SURFACE HIGH PRESSURE CENTERED OVER THE WESTERN TIP OF KENTUCKY...
WITH RIDGING EXTENDING NORTHWARD INTO WISCONSIN. STRIPE OF
SNOW FROM YESTERDAY...ABOUT 100 MILES WIDE...SHOWING UP NICELY ON
VISIBLE SATELLITE IMAGERY. WITH SKIES CLEARING OUT EARLIER AND
COMBINED WITH THE FRESH SNOW COVER...TEMPERATURES PLUNGED SEVERAL
DEGREES BELOW THE ORIGINAL FORECAST FOR MORNING LOWS...SO THE
TEMPERATURES ARE RUNNING BEHIND THE HOURLY FORECAST FOR TODAY.
A NICE SOUTHERLY FLOW WILL BEGIN SETTING UP AFTER MIDDAY...AND
DAILY HIGHS MAY ACTUALLY OCCUR A BIT LATER THAN NORMAL...SO HAVE
NOT MADE MUCH CHANGE TO THE ACTUAL DAILY HIGHS. HAVE SENT SOME
UPDATED GRIDS TO REFLECT THESE CHANGES...AND WILL SEND A ZONE
UPDATE OUT SHORTLY.
GEELHART
&&
.AVIATION...
ISSUED 1112 AM CST MON MAR 5 2012
DIURNAL CUMULUS DEVELOPMENT DROPPED CEILINGS AS LOW AS 900 FEET
EARLIER THIS MORNING AT KCMI...BUT RECENT OBSERVATIONS ARE MORE
AROUND 2000-2500 FEET. RUC CU-RULE GUIDANCE SHOWING SCATTERED
CLOUDS CONTINUING ACROSS EAST CENTRAL ILLINOIS THROUGH MID
AFTERNOON...AND THESE SHOULD RISE INTO VFR RANGE THROUGH EARLY
AFTERNOON.
MAIN CONCERN AT THE TAF SITES IS WITH WINDS...BOTH SURFACE AND
ALOFT. PRESSURE GRADIENT WILL TIGHTEN UP THIS EVENING AS A STORM
SYSTEM MOVES ACROSS THE PLAINS. SHOULD SEE SURFACE GUSTS TO AROUND
20-25 KNOTS BY 06Z AT ALL SITES. FORECAST SOUNDINGS STILL SHOWING
LLWS DEVELOPING AROUND 1500 FEET BY 06Z. FULL SUNSHINE ON TUESDAY
SHOULD MIX DOWN THESE HIGH WINDS EASILY...AND HAVE BROUGHT GUSTS
UP TO AROUND 30 KNOTS OR SO BY THE END OF THE FORECAST PERIOD.
GEELHART
&&
.PREV DISCUSSION...
ISSUED 317 AM CST MON MAR 5 2012
MUCH OF THE MIDWEST IN THE WAKE OF SOME LIGHT SNOWFALL IN
ASSOCIATION WITH A CLIPPER SYSTEM THAT IS EXITING TO THE EAST.
NORTHWESTERLY FLOW DOMINATING MUCH OF THE MIDWEST WITH A TROF OVER
THE ERN CONUS...AND WEAK RIDGING OVER THE WEST. PATTERN ABOUT TO
SHIFT OVERALL...WITH RIDGING BUILDING INTO THE MIDWEST AND A GENERAL
WARMING TREND...PARTICULARLY KICKING IN IN THE OVERNIGHT TONIGHT.
FIRST ISSUE WILL BE WITH THE NEXT SYSTEM ON ITS WAY LATE WED/THRU
THURSDAY AS THE NEXT TROF DIGS IN OVER THE PAC WEST. MODELS STILL
HAVING A BIT OF A PROBLEM COMING TO A CONSENSUS ABOUT HANDLING THE
UPPER LOW AND THE PATTERN SHIFT. FOR THE LAST 24 HRS...ECMWF AND GFS
ARE STARTING TO COME AROUND...BUT MAJORITY OF THE DIFFERENCES WILL
MAKE AN IMPACT ON ILX WEATHER. KEEPING A CONSERVATIVE BLEND.
SHORT TERM...TODAY AND TOMORROW...
STILL A BIT COOL TODAY...AND MORNING WARM UP MAY BE DELAYED A BIT
UNTIL THE SUNSHINE CAN HELP MELT THE 1-2 INCHES OF SNOW. TOMORROW
SIGNIFICANTLY WARMER AS LLVL SOUTHERLY WINDS AND RATHER AGGRESSIVE
WAA KICKS IN IN THE OVERNIGHT HOURS. WINDY TUESDAY WITH SUSTAINED
WINDS IN THE 30 TO 35 MPH RANGE PUSHING PARTS OF ILX INTO WIND
ADVISORY CRITERIA AS STUBBORN HIGH PRESSURE HOLDS ON OVER THE
ATLANTIC COAST AND ANOTHER WAVE DIVES INTO THE WEST. PREVIOUS
CONCERNS FOR FIRE WEATHER ISSUES ON TUESDAY WILL LIKELY BE MITIGATED
SOMEWHAT BY THE IMPACT OF THE WIDESPREAD QPF FROM THE CLIPPER
IMPACTING THE LLVL MOISTURE PROFILE FOR ILX. A BETTER PICTURE LIKELY
LATER THIS EVENING ONCE THE SNOW MELT AND MIXING FROM THE DAY
BECOMES CLEARER. AT ANY RATE...RH IS SOMETHING TO WATCH...AS THE
WINDS WILL MOST DEFINITELY BE AN ISSUE FOR TUESDAY.
LONG TERM...WEDNESDAY THROUGH SUNDAY...
WEATHER WISE...FRONT/LOW PRESSURE MOVING THROUGH THE MIDWEST LATE
WED AFTERNOON...WITH PLENTY OF WAA AHEAD OF IT...INSTABILITY WILL
LEND ITSELF TO THUNDER WITH THE STORMS THEMSELVES. SLIGHTLY COOLER
BEHIND THE FRONT...BUT A SPLIT FLOW PATTERN WORKING INTO THE CONUS
WILL MODERATE ANY DROP QUICKLY. AS FAR AS MODEL PERFORMANCE...A BIT
OF A MESS...THOUGH STARTING TO REPEAT THE SOLUTION OF A SPLIT FLOW
SITUATION SETTING UP MIDWEEK... EJECTING ONE SFC LOW AND A FRONT WED
EVENING/THU MORNING...AND HOLDING HALF OF THE WAVE BACK OVER THE
DESERT SW AND CUTTING OFF THE 500MB LOW TO PUSH OUT LATER IN THE
WEEKEND. 00Z RUN OF THE ECMWF NOT HANDLING THE SPLIT OF THE ENERGY
OVERALL VERY WELL...AND SPREADING A BIT OF CONVECTIVE FEEDBACK
THROUGH ITS QPF FIELDS. AS A RESULT...NOT HOLDING TOO TIGHTLY TO ITS
SOLUTION THIS RUN. SEEMS THE GFS IS ADJUSTING A BIT MORE TO THE
SPLIT...AND SLIGHTLY WEAKENING THE CUT OFF LOW...AS IT HAD SPLIT THE
FLOW A COUPLE SOLUTIONS AGO. EITHER WAY...NOT MAKING MASSIVE CHANGES
TO THE BLEND IN THE EXTENDED...BUT LIKE THE TREND OF THE GFS FOR
THIS RUN IN PARTICULAR AS THE ECMWF WORKS SOME KINKS OUT.
HJS
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1013 AM CST MON MAR 5 2012
.DISCUSSION...
ISSUED 1012 AM CST MON MAR 5 2012
SURFACE HIGH PRESSURE CENTERED OVER THE WESTERN TIP OF KENTUCKY...
WITH RIDGING EXTENDING NORTHWARD INTO WISCONSIN. STRIPE OF
SNOW FROM YESTERDAY...ABOUT 100 MILES WIDE...SHOWING UP NICELY ON
VISIBLE SATELLITE IMAGERY. WITH SKIES CLEARING OUT EARLIER AND
COMBINED WITH THE FRESH SNOW COVER...TEMPERATURES PLUNGED SEVERAL
DEGREES BELOW THE ORIGINAL FORECAST FOR MORNING LOWS...SO THE
TEMPERATURES ARE RUNNING BEHIND THE HOURLY FORECAST FOR TODAY.
A NICE SOUTHERLY FLOW WILL BEGIN SETTING UP AFTER MIDDAY...AND
DAILY HIGHS MAY ACTUALLY OCCUR A BIT LATER THAN NORMAL...SO HAVE
NOT MADE MUCH CHANGE TO THE ACTUAL DAILY HIGHS. HAVE SENT SOME
UPDATED GRIDS TO REFLECT THESE CHANGES...AND WILL SEND A ZONE
UPDATE OUT SHORTLY.
GEELHART
&&
.AVIATION...
ISSUED 515 AM CST MON MAR 5 2012
A FEW STRATOCU/STRATUS FRACTUS ARE DRIFTING SOUTHWARD THROUGH THE
AREA THIS MORNING...MAINLY AFFECTING CMI/DEC/BMI FOR THE FIRST
COUPLE OF HOURS. WINDS HAVE LIGHTENED UP AS HIGH PRESSURE APPROACHES
FROM MO AND THIS HAS RESULTED IN SOME VISIBILITIES LOWER THAN
10SM...BUT DO NOT EXPECT ANY RESTRICTIONS BELOW VFR RANGE. QUIET
WEATHER ON TAP TODAY AS THE MO SURFACE HIGH MOVES ACROSS SOUTHERN IL
AND ENDS UP NEAR THE APPALACHIANS BY 12Z TUE. LATEST RUC FORECAST
SOUNDINGS SUGGEST SOME STRATOCU REFORMATION LATE THIS MORNING AND
AFTERNOON MAINLY EAST. ANY BROKEN CEILINGS /MAINLY AFFECTING CMI/
SHOULD BE ABOVE 3K FT. RETURN FLOW ON THE BACK SIDE OF THE HIGH WILL
STRENGTHEN SOUTH WINDS AFTER 00Z TUE...WITH 15-20 KTS COMMON ALONG
WITH HIGHER GUSTS. DESPITE THE SOUTHERLY FLOW...NO SIGNIFICANT LOW
LEVEL MOISTURE RETURN IS FORECAST UNTIL WELL AFTER THIS TAF PERIOD.
04
&&
.PREV DISCUSSION...
ISSUED 317 AM CST MON MAR 5 2012
MUCH OF THE MIDWEST IN THE WAKE OF SOME LIGHT SNOWFALL IN
ASSOCIATION WITH A CLIPPER SYSTEM THAT IS EXITING TO THE EAST.
NORTHWESTERLY FLOW DOMINATING MUCH OF THE MIDWEST WITH A TROF OVER
THE ERN CONUS...AND WEAK RIDGING OVER THE WEST. PATTERN ABOUT TO
SHIFT OVERALL...WITH RIDGING BUILDING INTO THE MIDWEST AND A GENERAL
WARMING TREND...PARTICULARLY KICKING IN IN THE OVERNIGHT TONIGHT.
FIRST ISSUE WILL BE WITH THE NEXT SYSTEM ON ITS WAY LATE WED/THRU
THURSDAY AS THE NEXT TROF DIGS IN OVER THE PAC WEST. MODELS STILL
HAVING A BIT OF A PROBLEM COMING TO A CONSENSUS ABOUT HANDLING THE
UPPER LOW AND THE PATTERN SHIFT. FOR THE LAST 24 HRS...ECMWF AND GFS
ARE STARTING TO COME AROUND...BUT MAJORITY OF THE DIFFERENCES WILL
MAKE AN IMPACT ON ILX WEATHER. KEEPING A CONSERVATIVE BLEND.
SHORT TERM...TODAY AND TOMORROW...
STILL A BIT COOL TODAY...AND MORNING WARM UP MAY BE DELAYED A BIT
UNTIL THE SUNSHINE CAN HELP MELT THE 1-2 INCHES OF SNOW. TOMORROW
SIGNIFICANTLY WARMER AS LLVL SOUTHERLY WINDS AND RATHER AGGRESSIVE
WAA KICKS IN IN THE OVERNIGHT HOURS. WINDY TUESDAY WITH SUSTAINED
WINDS IN THE 30 TO 35 MPH RANGE PUSHING PARTS OF ILX INTO WIND
ADVISORY CRITERIA AS STUBBORN HIGH PRESSURE HOLDS ON OVER THE
ATLANTIC COAST AND ANOTHER WAVE DIVES INTO THE WEST. PREVIOUS
CONCERNS FOR FIRE WEATHER ISSUES ON TUESDAY WILL LIKELY BE MITIGATED
SOMEWHAT BY THE IMPACT OF THE WIDESPREAD QPF FROM THE CLIPPER
IMPACTING THE LLVL MOISTURE PROFILE FOR ILX. A BETTER PICTURE LIKELY
LATER THIS EVENING ONCE THE SNOW MELT AND MIXING FROM THE DAY
BECOMES CLEARER. AT ANY RATE...RH IS SOMETHING TO WATCH...AS THE
WINDS WILL MOST DEFINITELY BE AN ISSUE FOR TUESDAY.
LONG TERM...WEDNESDAY THROUGH SUNDAY...
WEATHER WISE...FRONT/LOW PRESSURE MOVING THROUGH THE MIDWEST LATE
WED AFTERNOON...WITH PLENTY OF WAA AHEAD OF IT...INSTABILITY WILL
LEND ITSELF TO THUNDER WITH THE STORMS THEMSELVES. SLIGHTLY COOLER
BEHIND THE FRONT...BUT A SPLIT FLOW PATTERN WORKING INTO THE CONUS
WILL MODERATE ANY DROP QUICKLY. AS FAR AS MODEL PERFORMANCE...A BIT
OF A MESS...THOUGH STARTING TO REPEAT THE SOLUTION OF A SPLIT FLOW
SITUATION SETTING UP MIDWEEK... EJECTING ONE SFC LOW AND A FRONT WED
EVENING/THU MORNING...AND HOLDING HALF OF THE WAVE BACK OVER THE
DESERT SW AND CUTTING OFF THE 500MB LOW TO PUSH OUT LATER IN THE
WEEKEND. 00Z RUN OF THE ECMWF NOT HANDLING THE SPLIT OF THE ENERGY
OVERALL VERY WELL...AND SPREADING A BIT OF CONVECTIVE FEEDBACK
THROUGH ITS QPF FIELDS. AS A RESULT...NOT HOLDING TOO TIGHTLY TO ITS
SOLUTION THIS RUN. SEEMS THE GFS IS ADJUSTING A BIT MORE TO THE
SPLIT...AND SLIGHTLY WEAKENING THE CUT OFF LOW...AS IT HAD SPLIT THE
FLOW A COUPLE SOLUTIONS AGO. EITHER WAY...NOT MAKING MASSIVE CHANGES
TO THE BLEND IN THE EXTENDED...BUT LIKE THE TREND OF THE GFS FOR
THIS RUN IN PARTICULAR AS THE ECMWF WORKS SOME KINKS OUT.
HJS
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
515 AM CST MON MAR 5 2012
.DISCUSSION...
ISSUED 317 AM CST MON MAR 5 2012
MUCH OF THE MIDWEST IN THE WAKE OF SOME LIGHT SNOWFALL IN
ASSOCIATION WITH A CLIPPER SYSTEM THAT IS EXITING TO THE EAST.
NORTHWESTERLY FLOW DOMINATING MUCH OF THE MIDWEST WITH A TROF OVER
THE ERN CONUS...AND WEAK RIDGING OVER THE WEST. PATTERN ABOUT TO
SHIFT OVERALL...WITH RIDGING BUILDING INTO THE MIDWEST AND A GENERAL
WARMING TREND...PARTICULARLY KICKING IN IN THE OVERNIGHT TONIGHT.
FIRST ISSUE WILL BE WITH THE NEXT SYSTEM ON ITS WAY LATE WED/THRU
THURSDAY AS THE NEXT TROF DIGS IN OVER THE PAC WEST. MODELS STILL
HAVING A BIT OF A PROBLEM COMING TO A CONSENSUS ABOUT HANDLING THE
UPPER LOW AND THE PATTERN SHIFT. FOR THE LAST 24 HRS...ECMWF AND GFS
ARE STARTING TO COME AROUND...BUT MAJORITY OF THE DIFFERENCES WILL
MAKE AN IMPACT ON ILX WEATHER. KEEPING A CONSERVATIVE BLEND.
SHORT TERM...TODAY AND TOMORROW...
STILL A BIT COOL TODAY...AND MORNING WARM UP MAY BE DELAYED A BIT
UNTIL THE SUNSHINE CAN HELP MELT THE 1-2 INCHES OF SNOW. TOMORROW
SIGNIFICANTLY WARMER AS LLVL SOUTHERLY WINDS AND RATHER AGGRESSIVE
WAA KICKS IN IN THE OVERNIGHT HOURS. WINDY TUESDAY WITH SUSTAINED
WINDS IN THE 30 TO 35 MPH RANGE PUSHING PARTS OF ILX INTO WIND
ADVISORY CRITERIA AS STUBBORN HIGH PRESSURE HOLDS ON OVER THE
ATLANTIC COAST AND ANOTHER WAVE DIVES INTO THE WEST. PREVIOUS
CONCERNS FOR FIRE WEATHER ISSUES ON TUESDAY WILL LIKELY BE MITIGATED
SOMEWHAT BY THE IMPACT OF THE WIDESPREAD QPF FROM THE CLIPPER
IMPACTING THE LLVL MOISTURE PROFILE FOR ILX. A BETTER PICTURE LIKELY
LATER THIS EVENING ONCE THE SNOW MELT AND MIXING FROM THE DAY
BECOMES CLEARER. AT ANY RATE...RH IS SOMETHING TO WATCH...AS THE
WINDS WILL MOST DEFINITELY BE AN ISSUE FOR TUESDAY.
LONG TERM...WEDNESDAY THROUGH SUNDAY...
WEATHER WISE...FRONT/LOW PRESSURE MOVING THROUGH THE MIDWEST LATE
WED AFTERNOON...WITH PLENTY OF WAA AHEAD OF IT...INSTABILITY WILL
LEND ITSELF TO THUNDER WITH THE STORMS THEMSELVES. SLIGHTLY COOLER
BEHIND THE FRONT...BUT A SPLIT FLOW PATTERN WORKING INTO THE CONUS
WILL MODERATE ANY DROP QUICKLY. AS FAR AS MODEL PERFORMANCE...A BIT
OF A MESS...THOUGH STARTING TO REPEAT THE SOLUTION OF A SPLIT FLOW
SITUATION SETTING UP MIDWEEK... EJECTING ONE SFC LOW AND A FRONT WED
EVENING/THU MORNING...AND HOLDING HALF OF THE WAVE BACK OVER THE
DESERT SW AND CUTTING OFF THE 500MB LOW TO PUSH OUT LATER IN THE
WEEKEND. 00Z RUN OF THE ECMWF NOT HANDLING THE SPLIT OF THE ENERGY
OVERALL VERY WELL...AND SPREADING A BIT OF CONVECTIVE FEEDBACK
THROUGH ITS QPF FIELDS. AS A RESULT...NOT HOLDING TOO TIGHTLY TO ITS
SOLUTION THIS RUN. SEEMS THE GFS IS ADJUSTING A BIT MORE TO THE
SPLIT...AND SLIGHTLY WEAKENING THE CUT OFF LOW...AS IT HAD SPLIT THE
FLOW A COUPLE SOLUTIONS AGO. EITHER WAY...NOT MAKING MASSIVE CHANGES
TO THE BLEND IN THE EXTENDED...BUT LIKE THE TREND OF THE GFS FOR
THIS RUN IN PARTICULAR AS THE ECMWF WORKS SOME KINKS OUT.
HJS
&&
.AVIATION...
ISSUED 515 AM CST MON MAR 5 2012
A FEW STRATOCU/STRATUS FRACTUS ARE DRIFTING SOUTHWARD THROUGH THE
AREA THIS MORNING...MAINLY AFFECTING CMI/DEC/BMI FOR THE FIRST
COUPLE OF HOURS. WINDS HAVE LIGHTENED UP AS HIGH PRESSURE APPROACHES
FROM MO AND THIS HAS RESULTED IN SOME VISIBILITIES LOWER THAN
10SM...BUT DO NOT EXPECT ANY RESTRICTIONS BELOW VFR RANGE. QUIET
WEATHER ON TAP TODAY AS THE MO SURFACE HIGH MOVES ACROSS SOUTHERN IL
AND ENDS UP NEAR THE APPALACHIANS BY 12Z TUE. LATEST RUC FORECAST
SOUNDINGS SUGGEST SOME STRATOCU REFORMATION LATE THIS MORNING AND
AFTERNOON MAINLY EAST. ANY BROKEN CEILINGS /MAINLY AFFECTING CMI/
SHOULD BE ABOVE 3K FT. RETURN FLOW ON THE BACK SIDE OF THE HIGH WILL
STRENGTHEN SOUTH WINDS AFTER 00Z TUE...WITH 15-20 KTS COMMON ALONG
WITH HIGHER GUSTS. DESPITE THE SOUTHERLY FLOW...NO SIGNIFICANT LOW
LEVEL MOISTURE RETURN IS FORECAST UNTIL WELL AFTER THIS TAF PERIOD.
04
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1146 AM CST MON MAR 5 2012
.AVIATION...
AS FOR NORTH CENTRAL AND NORTHEASTERN IA CLOUD TRENDS...LLVL RIDGE
AXIS AND DEVELOPING LLVL SOUTH-SOUTHEASTERLY RETURN FLOW KEEPING
THE LOW DECK AT BAY WEST AND NORTHWEST OF THE CID AND DBQ
TERMINALS...AND THESE SITES SHOULD NOW JUST GET CLIPPED BY SOME
PASSING VFR LEVEL AC FROM THE NORTHWEST. REST OF THE TERMINALS
JUST WILL EXPERIENCE SOME FEW TO SCTRD CU DEVELOPMENT FROM 2-3K FT
AGL DEVELOPING OUT OF MELTING SNOW FIELDS. MID CLOUDS OVER THE
DAKOTAS STILL ON TRACK TO PROPAGATE EAST-SOUTHEASTWARD ACROSS THE
REGION LATER THIS AFTN AND INTO THE EVENING BEFORE MOVING OFF
AGAIN FOR MAINLY CLEAR SKIES OVERNIGHT. SFC WINDS TO REMAIN S/SE
AT 10-20 KTS OVERNIGHT IN TIGHTENING PRESSURE GRADIENT. COULD SEE
SOME HIGHER GUSTS AT TIMES. SHORT RANGE MODEL FCST SOUNDINGS
CONTINUE TO SHOW 45-50 KTS OF WIND AT 1500-1800 FT AGL AFT 06Z AND
WILL KEEP THE LLWS ALREADY MENTIONED IN PREVIOUS TAF PACKAGE.
BRISK SOUTHERLY SFC WINDS GUSTING UP TO 25+ KTS BY END OF TAF
CYCLE TOMORROW. ..12..
&&
.PREV DISCUSSION... /ISSUED 616 AM CST MON MAR 5 2012/
.UPDATE...
KEEPING AN EYE ON CLOUD TRENDS AND WILL UPDATE AS NEEDED. AXIS OF
LOW CLOUDS SLIDING EWD FROM CENTRAL IA WITH MORE WIDESPREAD AREA
OVER NORTHERN IA EXPANDING SEWD SOME PER SATL LOOP. THESE CLOUDS
LINE UP WELL WITH RUC 925-850 MB MOISTURE ADVECTION WHICH WEAKENS
WHILE MOVING INTO PORTIONS OF EASTERN IA THIS AM. COMBINATION OF
THIS AND SFC HEATING OVER FRESH SNOW COVER LIKELY TO FIRE SCT-BKN
ST/SC BY MID AM... AND LAST COUPLE OF RUNS OF HRRR CIG PRODUCT
DEPICTING THIS. BOTTOM LINE... SKY COVER MAY NEED TO BE INCREASED
AND THIS TO HAVE BIG RAMIFICATIONS ON HIGH TEMPS AND GROWING CONCERNS
TEMPS TOO WARM SOME AREAS GIVEN SINGLE DIGITS OVER PORTIONS OF
EASTERN IA FROM KIIB-KCID-KIOW-KAWG AND WESTWARD.
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
616 AM CST MON MAR 5 2012
.UPDATE...
KEEPING AN EYE ON CLOUD TRENDS AND WILL UPDATE AS NEEDED. AXIS OF
LOW CLOUDS SLIDING EWD FROM CENTRAL IA WITH MORE WIDESPREAD AREA
OVER NORTHERN IA EXPANDING SEWD SOME PER SATL LOOP. THESE CLOUDS
LINE UP WELL WITH RUC 925-850 MB MOISTURE ADVECTION WHICH WEAKENS
WHILE MOVING INTO PORTIONS OF EASTERN IA THIS AM. COMBINATION OF
THIS AND SFC HEATING OVER FRESH SNOW COVER LIKELY TO FIRE SCT-BKN
ST/SC BY MID AM... AND LAST COUPLE OF RUNS OF HRRR CIG PRODUCT
DEPICTING THIS. BOTTOM LINE... SKY COVER MAY NEED TO BE INCREASED
AND THIS TO HAVE BIG RAMIFICATIONS ON HIGH TEMPS AND GROWING CONCERNS
TEMPS TOO WARM SOME AREAS GIVEN SINGLE DIGITS OVER PORTIONS OF
EASTERN IA FROM KIIB-KCID-KIOW-KAWG AND WESTWARD.
&&
.PREV DISCUSSION... /ISSUED 552 AM CST MON MAR 5 2012/
AVIATION...
INITIAL CONCERN IS CLOUD TRENDS/CIGS THEN LLWS TNGT. SKIES ARE SKC
EARLY THIS AM BUT WATCHING AXIS OF LOW CLOUDS PASSING THROUGH
CENTRAL IA WHICH COINCIDES WITH RIDGE AXIS WITH MOISTURE BENEATH
SUBSIDENCE INVERSION. MOST CONCENTRATED AREA OF LOW CLOUDS WAS
OVER NORTHERN IA WITH RECENT SATL LOOP SHOWING SOME
EXPANSION/DEVELOPMENT S/SE. MODELS NOT HANDLING LOW CLOUDS TRENDS.
LATEST RUC MOISTURE ADVECTION PROGS IN 925-950 MB LAYER THOUGH
DOING REASONABLY WELL WITH CLOUDS AND SHOWS MOISTURE ADVECTION
WORKING INTO EASTERN IA 12Z-15Z WHILE WEAKENING CONSIDERABLY. HAVE
ADDED ST/SC WITH MVFR BASES AT THE TERMINALS TDY BUT NO CIGS
MENTIONED ATTIM... AND WILL MONITOR SATL AND OB TRENDS FOR
POSSIBLY NEEDING TO INTRODUCE IFR TO LOW MVFR CIGS ESPECIALLY AT
KCID AND KDBQ. OTHERWISE... MID CLOUDS OVER THE DAKOTAS WILL
PROPAGATE E/SE AND ACROSS THE REGION THIS AFTN EXITING N/E
SECTIONS THIS EVE. WINDS IN PROCESS OF BECOMING LIGHT AND VARIABLE
OR LIGHT W/SW AS RIDGE AXIS APPROACHES. THIS AFTN WINDS WILL
INCREASE TO AROUND 10-15 KTS FROM THE SOUTH. WINDS TO REMAIN S/SE
AT 10-20 KTS TNGT IN TIGHTENING MSLP GRADIENT. COULD SEE SOME
HIGHER GUSTS AT TIMES. NAM AND GFS BUFR SOUNDINGS SHOW 45-50 KTS
OF WIND AT 1500-1800 FT AGL AFT 06Z AND HAVE ADDED MENTION OF LLWS.
PREV DISCUSSION... /ISSUED 322 AM CST MON MAR 5 2012/
SYNOPSIS...
SHORTWAVE /CLIPPER SYSTEM/ WHICH PRODUCED 1-3 INCH SNOWFALL ACCUMS
IN MANY AREAS MOSTLY WEST AND SOUTH OF QC YSTDY IS PASSING
THROUGH THE OH VLY EARLY THIS AM BRINGING ACCUMULATING SNOW
TO AREAS HARD HIT BY TORNADOES LAST FRI. IN WAKE... HEIGHTS ALOFT
WERE BUILDING THROUGH THE MIDWEST WHILE SFC ANTICYCLONE WAS
CENTERED OVER THE MO RVR VLY EARLY THIS AM. INCREASING SUBSIDENCE
HAS LED TO CLEARING SKIES OVER MUCH OF THE REGION EXCEPT
FOR AREAS NORTHEAST OF QC. THIS HAS LED TO LARGE TEMP CONTRAST
RANGING FROM TEENS AND EVEN A FEW SINGLE DIGITS WHERE SKIES HAVE
CLEARED AND OVER FRESH SNOW COVER... TO M/U 20S IN AREAS WHERE
CLOUDS PERSIST.
SHORT TERM...TODAY AND TONIGHT...
FAIRLY CHALLENGING TEMP FCST WHICH IS THE MAIN CONCERN DURING THE
PD.
TDY... SFC ANTICYCLONE TO SLIDE S/E OF CWA WITH RIDGE AXIS PASSING
BY MIDDAY. THUS COLD ADVECTION TO SUBSIDE BY MID AM WITH NEUTRAL
ADVECTION THROUGH MIDDAY AS WINDS GO LIGHT AND/OR BEGIN BACKING TO
S/SW. THIS AFTN WILL FEATURE ONSET OF WARM ADVECTION AS S/SE WINDS
ON BACKSIDE OF DEPARTING RIDGE INCREASE TO AROUND 10-15 KTS MID-LATE
PM. SKIES TO BE GENERALLY SUNNY/MOSUNNY THIS AM WITH INCREASING
SUBSIDENCE... AND ABUNDANT SOLAR INSOLATION TO GO TO WORK ON SNOW
COVER. FIRST CONCERN IS WITH FRESH 2-3 INCHES IN SOME AREAS THAT MUCH
OF SOLAR ENERGY WILL GO TO MELTING SNOW MAKING IT DIFFICULT TO WARM
ESPECIALLY WITH VERY COLD START WITH SINGLE DIGITS AND LOWER TEENS IN
SOME AREAS. NEXT CONCERN AND POTENTIAL FLY IN OINTMENT OF TEMP FCST
IS MODEL RH PROGS WHICH SUGGEST INCREASE IN MID LEVEL CLOUDS WITH THE
WARM ADVECTION ALOFT. EARLY AM SATL BEARS OUT THESE DEVELOPING CLOUDS
OVER THE DAKOTAS WHICH ARE SLIDING E/SE. THESE LIKELY TIME IN DURING
PEAK HEATING AND MAY BE FAIRLY OPAQUE OR THICK ENOUGH TO BLOCK OUT SUN
MOSTLY NORTH 1/3-1/2. THUS COULD ALSO NEGATE SOME OF WARMING POTENTIAL.
TAKING ALL OF THE ABOVE INTO ACCOUNT HAVE NUDGED DOWN HIGHS FROM
PREVIOUS FCST IN MANY AREAS... WITH WIDESPREAD 30S. LIKELY TO SEE
STRONG TEMP GRADIENT SOUTH OF SNOW COVER WHERE PROGGED LOW LEVEL
THICKNESS AND VERIFICATION OF HIGHS FROM YSTDY WOULD SUPPORT M/U 40S
PORTIONS OF EXTREME SOUTHEAST IA AND NORTHEAST MO.
TNGT... WARM ADVECTION TO CONTINUE STRENGTHENING ON INCREASING AND
GUSTY S/SE WINDS 15-25 MPH. AS RESULT... NOT EXPECTING TOO MUCH
OF A DROP OFF ON TEMPS DESPITE MAINLY CLEAR SKIES. LOW LEVEL WARM
ADVECTION IS QUITE IMPRESSIVE WITH 925 MILLIBAR TEMPS CLIMBING 10+ DEGS
INTO GENERAL RANGE OF AROUND 4C NORTHEAST TO NEAR 10C SOUTHWEST BY 12Z.
SFC TEMPS TO RESPOND BY STEADILY CLIMBING THROUGH THE NIGHT THUS HAVE
CONTINUED WITH NON-STANDARD TEMP CURVE IN GRIDS. ..05..
LONG TERM...TUESDAY THROUGH SUNDAY...
WINDY AND MUCH WARMER WEATHER TUESDAY AND WEDNESDAY WILL BE FOLLOWED
BY A COLD FRONT THAT WILL PRODUCE WIDESPREAD LIGHT TO MODERATE
RAIN...AND A RETURN OF TEMPERATURES CLOSER TO NORMAL FOR THE LATTER
HALF OF THE WEEK. LATEST MODELS ARE IN GOOD AGREEMENT WITH LATE
WED/WED NIGHT TIMING OF THIS FRONT AND FORECAST CONFIDENCE IS ABOVE
AVERAGE WITH THIS SYSTEM. HOWEVER...THE FOLLOWING SYSTEM FOR THE
WEEKEND...CONSISTING OF AN UPPER LOW EMBEDDED IN A SPLIT FLOW
PATTERN...HAS A HIGH LEVEL OF UNCERTAINTY WITH POOR MODEL AGREEMENT.
TUESDAY...THE AREA WILL BE BATHED IN A STRONG WARM ADVECTION RETURN
FLOW AHEAD OF A DEVELOPING LEE TROUGH IN THE SW FLOW ALOFT. HAVE
KEPT FORECAST HIGHS IN A RANGE FROM THE UPPER 50S NORTH TO THE UPPER
60S IN THE FAR SOUTH. THIS IS CLOSE TO THE WARMER GFS/MAV AND ECMWF
GUIDANCE...CONSISTENT WITH THEIR FORECAST SOUNDINGS SHOWING MIXING
OUT TO AT LEAST 900 MB. THE NAM/MET APPEARED TO BE HANGING ONTO OUR
SNOW COVER TOO LONG...WITH ITS GUIDANCE HOLDING THE HIGHWAY 20
CORRIDOR IN THE 40S. THIS SNOW COVER BIAS WAS WAS ALSO REFLECTED IN
LOWER NAM SURFACE WINDS OVER THE NORTH AND CENTRAL PORTIONS OF THE
FORECAST AREA. COUNTING ON THE SNOW TO BE LARGELY GONE BY MID
MORNING...HAVE GONE CLOSER TO THE GFS AND ECMWF WITH WIDESPREAD 20
TO 25 MPH WINDS WITH GUSTS TO NEAR 35 MPH THROUGH THE DAY. THESE
WINDS SHOULD DIMINISH SOME TUE NIGHT...BUT REMAIN BRISK...HOLDING
TEMPERATURES IN THE 40S TO LOWER 50S THROUGH THE NIGHT.
WEDNESDAY INTO WEDNESDAY NIGHT...00Z MODELS HAVE TRENDED A BIT
SLOWER WITH THE TIMING OF THE COLD FRONT AND HAVE DELAYED THE
ONSET OF RAIN CHANCES...ESPECIALLY ACROSS THE EAST DURING THE DAY.
LOW LEVEL MOISTURE RETURN ON DEVELOPING 50 TO NEAR 70 KT WINDS AT
850 SHOULD RESULT IN MOSTLY CLOUDY SKIES THROUGH THE DAY...WHICH
WILL BE NEEDED TO CONTAIN HIGH TEMPERATURES TO THE 50S TO LOWER 60S.
DEVELOPING SHOWERS SHOULD ALSO HELP TO HOLD TEMPERATURES DOWN SOME.
THE POTENTIAL FOR THUNDERSTORMS ON ELEVATED CONVECTION LOOKS LIMITED
DUE TO A WARM MID LEVEL CAPPING INVERSION SHOWN ON SOUNDINGS
INCREASING IN THE AFTERNOON. THIS CAP WEAKENS EARLY WED NIGHT...AND
WITH SUFFICIENTLY STEEP 850MB TO 500 MB LAPSE RATES OF TEMPERATURE
AND THETAE...HAVE PLACED ISOLATED THUNDERSTORMS ACROSS THE SE HALF
OF THE AREA FOR POSSIBLE CONVECTION ALONG THE COLD FRONT. THE BULK
OF THE SHOWERS OVERNIGHT ARE EXPECTED TO BE POST FRONTAL. HAVE GONE
WITH A MODEL BLEND OF WIDESPREAD .25 TO .50 QPF AMOUNTS...WHICH MAY
NEED TO BE FURTHER REFINED UPWARDS BASED ON PW VALUES THAT ARE SHOWN
PUSHING 1 INCH IN THE CONVERGENCE ALONG THE FRONT.
ONCE THE FRONT EXITS THE FAR SOUTHEAST EARLY THU...THE REMAINDER OF
THE WORKWEEK LOOKS DRY WITH NEAR TO ABOVE NORMAL TEMPERATURES AS
HIGH PRESSURE TRAVERSES THE REGION AT THE SURFACE UNDER A NW FLOW ALOFT.
OVER THE WEEKEND...THE GFS AND ECMWF HAVE TRENDED TOWARD BETTER
CONTINUITY OVER THE PAST COUPLE RUNS DEPICTING AN UPPER LOW OVER THE
CENTRAL U.S...BUT DIFFER IN BOTH THE PLACEMENT OF THIS LOW AND THE
PHASING OF WAVES IN THE SPLIT FLOW. THIS RESULTS IN A LARGE
DIFFERENCE IN BOTH THE PLACEMENT AND TRACK OF A SURFACE LOW
PRESSURE SYSTEM. OVERALL...THE ADVERTISED PATTERN IS MORE FAVORABLE
FOR PRECIPITATION IN THE REGION AND POPS HAVE BEEN INCREASED FOR
SATURDAY THROUGH SUNDAY. THIS DEVELOPING PATTERN CONTINUES TO
SUPPORT WARMER TEMPERATURES THAN PREVIOUS MODEL RUNS THAT WERE MORE
AMPLIFIED AND SUGGESTED A DEEPER UPPER LEVEL TROUGH. TEMPERATURES
THUS CONTINUE TO BE ADJUSTED UPWARDS. FORECAST NOW HAS HIGHS IN THE
40S SATURDAY...THEN 50S SUNDAY WITH OVERNIGHT LOWS IN THE 30S.
SHEETS..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
552 AM CST MON MAR 5 2012
.AVIATION...
INITIAL CONCERN IS CLOUD TRENDS/CIGS THEN LLWS TNGT. SKIES ARE SKC
EARLY THIS AM BUT WATCHING AXIS OF LOW CLOUDS PASSING THROUGH
CENTRAL IA WHICH COINCIDES WITH RIDGE AXIS WITH MOISTURE BENEATH
SUBSIDENCE INVERSION. MOST CONCENTRATED AREA OF LOW CLOUDS WAS
OVER NORTHERN IA WITH RECENT SATL LOOP SHOWING SOME
EXPANSION/DEVELOPMENT S/SE. MODELS NOT HANDLING LOW CLOUDS TRENDS.
LATEST RUC MOISTURE ADVECTION PROGS IN 925-950 MB LAYER THOUGH
DOING REASONABLY WELL WITH CLOUDS AND SHOWS MOISTURE ADVECTION
WORKING INTO EASTERN IA 12Z-15Z WHILE WEAKENING CONSIDERABLY. HAVE
ADDED ST/SC WITH MVFR BASES AT THE TERMINALS TDY BUT NO CIGS
MENTIONED ATTIM... AND WILL MONITOR SATL AND OB TRENDS FOR
POSSIBLY NEEDING TO INTRODUCE IFR TO LOW MVFR CIGS ESPECIALLY AT
KCID AND KDBQ. OTHERWISE... MID CLOUDS OVER THE DAKOTAS WILL
PROPAGATE E/SE AND ACROSS THE REGION THIS AFTN EXITING N/E
SECTIONS THIS EVE. WINDS IN PROCESS OF BECOMING LIGHT AND VARIABLE
OR LIGHT W/SW AS RIDGE AXIS APPROACHES. THIS AFTN WINDS WILL
INCREASE TO AROUND 10-15 KTS FROM THE SOUTH. WINDS TO REMAIN S/SE
AT 10-20 KTS TNGT IN TIGHTENING MSLP GRADIENT. COULD SEE SOME
HIGHER GUSTS AT TIMES. NAM AND GFS BUFR SOUNDINGS SHOW 45-50 KTS
OF WIND AT 1500-1800 FT AGL AFT 06Z AND HAVE ADDED MENTION OF LLWS.
&&
.PREV DISCUSSION... /ISSUED 322 AM CST MON MAR 5 2012/
SYNOPSIS...
SHORTWAVE /CLIPPER SYSTEM/ WHICH PRODUCED 1-3 INCH SNOWFALL ACCUMS
IN MANY AREAS MOSTLY WEST AND SOUTH OF QC YSTDY IS PASSING
THROUGH THE OH VLY EARLY THIS AM BRINGING ACCUMULATING SNOW
TO AREAS HARD HIT BY TORNADOES LAST FRI. IN WAKE... HEIGHTS ALOFT
WERE BUILDING THROUGH THE MIDWEST WHILE SFC ANTICYCLONE WAS
CENTERED OVER THE MO RVR VLY EARLY THIS AM. INCREASING SUBSIDENCE
HAS LED TO CLEARING SKIES OVER MUCH OF THE REGION EXCEPT
FOR AREAS NORTHEAST OF QC. THIS HAS LED TO LARGE TEMP CONTRAST
RANGING FROM TEENS AND EVEN A FEW SINGLE DIGITS WHERE SKIES HAVE
CLEARED AND OVER FRESH SNOW COVER... TO M/U 20S IN AREAS WHERE
CLOUDS PERSIST.
SHORT TERM...TODAY AND TONIGHT...
FAIRLY CHALLENGING TEMP FCST WHICH IS THE MAIN CONCERN DURING THE
PD.
TDY... SFC ANTICYCLONE TO SLIDE S/E OF CWA WITH RIDGE AXIS PASSING
BY MIDDAY. THUS COLD ADVECTION TO SUBSIDE BY MID AM WITH NEUTRAL
ADVECTION THROUGH MIDDAY AS WINDS GO LIGHT AND/OR BEGIN BACKING TO
S/SW. THIS AFTN WILL FEATURE ONSET OF WARM ADVECTION AS S/SE WINDS
ON BACKSIDE OF DEPARTING RIDGE INCREASE TO AROUND 10-15 KTS MID-LATE
PM. SKIES TO BE GENERALLY SUNNY/MOSUNNY THIS AM WITH INCREASING
SUBSIDENCE... AND ABUNDANT SOLAR INSOLATION TO GO TO WORK ON SNOW
COVER. FIRST CONCERN IS WITH FRESH 2-3 INCHES IN SOME AREAS THAT MUCH
OF SOLAR ENERGY WILL GO TO MELTING SNOW MAKING IT DIFFICULT TO WARM
ESPECIALLY WITH VERY COLD START WITH SINGLE DIGITS AND LOWER TEENS IN
SOME AREAS. NEXT CONCERN AND POTENTIAL FLY IN OINTMENT OF TEMP FCST
IS MODEL RH PROGS WHICH SUGGEST INCREASE IN MID LEVEL CLOUDS WITH THE
WARM ADVECTION ALOFT. EARLY AM SATL BEARS OUT THESE DEVELOPING CLOUDS
OVER THE DAKOTAS WHICH ARE SLIDING E/SE. THESE LIKELY TIME IN DURING
PEAK HEATING AND MAY BE FAIRLY OPAQUE OR THICK ENOUGH TO BLOCK OUT SUN
MOSTLY NORTH 1/3-1/2. THUS COULD ALSO NEGATE SOME OF WARMING POTENTIAL.
TAKING ALL OF THE ABOVE INTO ACCOUNT HAVE NUDGED DOWN HIGHS FROM
PREVIOUS FCST IN MANY AREAS... WITH WIDESPREAD 30S. LIKELY TO SEE
STRONG TEMP GRADIENT SOUTH OF SNOW COVER WHERE PROGGED LOW LEVEL
THICKNESS AND VERIFICATION OF HIGHS FROM YSTDY WOULD SUPPORT M/U 40S
PORTIONS OF EXTREME SOUTHEAST IA AND NORTHEAST MO.
TNGT... WARM ADVECTION TO CONTINUE STRENGTHENING ON INCREASING AND
GUSTY S/SE WINDS 15-25 MPH. AS RESULT... NOT EXPECTING TOO MUCH
OF A DROP OFF ON TEMPS DESPITE MAINLY CLEAR SKIES. LOW LEVEL WARM
ADVECTION IS QUITE IMPRESSIVE WITH 925 MILLIBAR TEMPS CLIMBING 10+ DEGS
INTO GENERAL RANGE OF AROUND 4C NORTHEAST TO NEAR 10C SOUTHWEST BY 12Z.
SFC TEMPS TO RESPOND BY STEADILY CLIMBING THROUGH THE NIGHT THUS HAVE
CONTINUED WITH NON-STANDARD TEMP CURVE IN GRIDS. ..05..
LONG TERM...TUESDAY THROUGH SUNDAY...
WINDY AND MUCH WARMER WEATHER TUESDAY AND WEDNESDAY WILL BE FOLLOWED
BY A COLD FRONT THAT WILL PRODUCE WIDESPREAD LIGHT TO MODERATE
RAIN...AND A RETURN OF TEMPERATURES CLOSER TO NORMAL FOR THE LATTER
HALF OF THE WEEK. LATEST MODELS ARE IN GOOD AGREEMENT WITH LATE
WED/WED NIGHT TIMING OF THIS FRONT AND FORECAST CONFIDENCE IS ABOVE
AVERAGE WITH THIS SYSTEM. HOWEVER...THE FOLLOWING SYSTEM FOR THE
WEEKEND...CONSISTING OF AN UPPER LOW EMBEDDED IN A SPLIT FLOW
PATTERN...HAS A HIGH LEVEL OF UNCERTAINTY WITH POOR MODEL AGREEMENT.
TUESDAY...THE AREA WILL BE BATHED IN A STRONG WARM ADVECTION RETURN
FLOW AHEAD OF A DEVELOPING LEE TROUGH IN THE SW FLOW ALOFT. HAVE
KEPT FORECAST HIGHS IN A RANGE FROM THE UPPER 50S NORTH TO THE UPPER
60S IN THE FAR SOUTH. THIS IS CLOSE TO THE WARMER GFS/MAV AND ECMWF
GUIDANCE...CONSISTENT WITH THEIR FORECAST SOUNDINGS SHOWING MIXING
OUT TO AT LEAST 900 MB. THE NAM/MET APPEARED TO BE HANGING ONTO OUR
SNOW COVER TOO LONG...WITH ITS GUIDANCE HOLDING THE HIGHWAY 20
CORRIDOR IN THE 40S. THIS SNOW COVER BIAS WAS WAS ALSO REFLECTED IN
LOWER NAM SURFACE WINDS OVER THE NORTH AND CENTRAL PORTIONS OF THE
FORECAST AREA. COUNTING ON THE SNOW TO BE LARGELY GONE BY MID
MORNING...HAVE GONE CLOSER TO THE GFS AND ECMWF WITH WIDESPREAD 20
TO 25 MPH WINDS WITH GUSTS TO NEAR 35 MPH THROUGH THE DAY. THESE
WINDS SHOULD DIMINISH SOME TUE NIGHT...BUT REMAIN BRISK...HOLDING
TEMPERATURES IN THE 40S TO LOWER 50S THROUGH THE NIGHT.
WEDNESDAY INTO WEDNESDAY NIGHT...00Z MODELS HAVE TRENDED A BIT
SLOWER WITH THE TIMING OF THE COLD FRONT AND HAVE DELAYED THE
ONSET OF RAIN CHANCES...ESPECIALLY ACROSS THE EAST DURING THE DAY.
LOW LEVEL MOISTURE RETURN ON DEVELOPING 50 TO NEAR 70 KT WINDS AT
850 SHOULD RESULT IN MOSTLY CLOUDY SKIES THROUGH THE DAY...WHICH
WILL BE NEEDED TO CONTAIN HIGH TEMPERATURES TO THE 50S TO LOWER 60S.
DEVELOPING SHOWERS SHOULD ALSO HELP TO HOLD TEMPERATURES DOWN SOME.
THE POTENTIAL FOR THUNDERSTORMS ON ELEVATED CONVECTION LOOKS LIMITED
DUE TO A WARM MID LEVEL CAPPING INVERSION SHOWN ON SOUNDINGS
INCREASING IN THE AFTERNOON. THIS CAP WEAKENS EARLY WED NIGHT...AND
WITH SUFFICIENTLY STEEP 850MB TO 500 MB LAPSE RATES OF TEMPERATURE
AND THETAE...HAVE PLACED ISOLATED THUNDERSTORMS ACROSS THE SE HALF
OF THE AREA FOR POSSIBLE CONVECTION ALONG THE COLD FRONT. THE BULK
OF THE SHOWERS OVERNIGHT ARE EXPECTED TO BE POST FRONTAL. HAVE GONE
WITH A MODEL BLEND OF WIDESPREAD .25 TO .50 QPF AMOUNTS...WHICH MAY
NEED TO BE FURTHER REFINED UPWARDS BASED ON PW VALUES THAT ARE SHOWN
PUSHING 1 INCH IN THE CONVERGENCE ALONG THE FRONT.
ONCE THE FRONT EXITS THE FAR SOUTHEAST EARLY THU...THE REMAINDER OF
THE WORKWEEK LOOKS DRY WITH NEAR TO ABOVE NORMAL TEMPERATURES AS
HIGH PRESSURE TRAVERSES THE REGION AT THE SURFACE UNDER A NW FLOW ALOFT.
OVER THE WEEKEND...THE GFS AND ECMWF HAVE TRENDED TOWARD BETTER
CONTINUITY OVER THE PAST COUPLE RUNS DEPICTING AN UPPER LOW OVER THE
CENTRAL U.S...BUT DIFFER IN BOTH THE PLACEMENT OF THIS LOW AND THE
PHASING OF WAVES IN THE SPLIT FLOW. THIS RESULTS IN A LARGE
DIFFERENCE IN BOTH THE PLACEMENT AND TRACK OF A SURFACE LOW
PRESSURE SYSTEM. OVERALL...THE ADVERTISED PATTERN IS MORE FAVORABLE
FOR PRECIPITATION IN THE REGION AND POPS HAVE BEEN INCREASED FOR
SATURDAY THROUGH SUNDAY. THIS DEVELOPING PATTERN CONTINUES TO
SUPPORT WARMER TEMPERATURES THAN PREVIOUS MODEL RUNS THAT WERE MORE
AMPLIFIED AND SUGGESTED A DEEPER UPPER LEVEL TROUGH. TEMPERATURES
THUS CONTINUE TO BE ADJUSTED UPWARDS. FORECAST NOW HAS HIGHS IN THE
40S SATURDAY...THEN 50S SUNDAY WITH OVERNIGHT LOWS IN THE 30S.
.SHEETS..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
302 PM MST MON MAR 5 2012
.SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT)
ISSUED AT 214 PM MST MON MAR 5 2012
EARLY AFTERNOON WV IMAGERY AND RUC H5 ANALYSIS SHOW WESTERLY FLOW
ACROSS THE INTER-MOUNTAIN WEST AND CENTRAL HIGH PLAINS. AT THE
SURFACE A LEE TROUGH HAS SHIFTED EAST TO BE NEAR THE COLORADO/KANSAS
STATE LINE.
THE TIGHTEST SURFACE GRADIENT REMAINS ALONG THE SE BORDER OF THE
CWA...WHERE THE WIND ADVISORY IS STILL IN EFFECT. WINDS HAVE JUST
STARTED TO REACH ADVISORY CRITERIA AT A FEW LOCATIONS EARLY THIS
AFTERNOON. WINDS WILL BEGIN TO DECREASE AS DAYTIME MIXING COMES TO
AN END. LOCATIONS CLOSER TO THE TROUGH AXIS MAY SEE WINDS DIMINISH
SOONER. FOR NOW THE WIND ADVISORY AND RED FLAG WARNING WILL BE
ALLOWED TO CONTINUE THROUGH 00Z...THOUGH WESTERN COUNTIES MAY BE
ALLOWED TO END EARLIER.
OVERNIGHT LOWS ARE TRICKY TONIGHT WITH WINDS AROUND 10 MPH POSSIBLE
EAST AND WEST OF SURFACE TROUGH...WITH EXACT LOCATION OF TROUGH AXIS
STILL IN QUESTION. IN ADDITION TO WINDS POSSIBLY ALLOWING FOR BETTER
OVERNIGHT MIXING...WAA WILL CONTINUE THROUGH THE NIGHT WITH H85
TEMPS 14-17C. CURRENT FORECAST CALLS FOR LOW TO MID 30S AND UPPER
30S IN THE EAST NEAR HILL CITY. THIS STILL MAY BE TOO COOL
CONSIDERING THE AIRMASS ALOFT.
NEAR RECORD HIGHS ARE STILL FORECAST FOR TUESDAY WITH SW FLOW AND A
VERY WARM AIRMASS IN PLACE ACROSS THE CWA. WITH AFTERNOON
TEMPERATURES TODAY REACHING THE MID 70S AT WESTERN LOCATIONS...THERE
SHOULD BE NO PROBLEMS REACHING THE UPPER 70S ON TUESDAY WHEN H85
TEMPS ARE FORECAST TO BE ABOUT 5C WARMER THAN TODAY. MANY LOCATIONS
WILL PROBABLY REACH 80F. RED FLAG CONDITIONS WILL ALSO BE POSSIBLE
TUESDAY WITH GUSTY WINDS VERY LOW RH VALUES EXPECTED ACROSS THE
AREA. A FIRE WEATHER WATCH REMAINS IN EFFECT FOR THE ENTIRE CWA
TUESDAY AFTERNOON AND EVENING.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 214 PM MST MON MAR 5 2012
TUESDAY NIGHT AND WEDNESDAY A TROUGH OF DIGS INTO THE WESTERN
UNITED STATES AND FORMS A CLOSED LOW IN THE VICINITY OF THE
4-CORNERS REGION. CLOUDS WILL BEGIN TO INCREASE AHEAD OF THIS
SYSTEM AND THE SURFACE LOW PRESSURE AREA IS SEEMINGLY SPLIT INTO
TWO PARTS...WITH THE LEADING PORTION DEEPENING IN THE LEE OF THE
ROCKIES AND MOVING SOUTHWARD INTO THE CENTRAL HIGH PLAINS EARLY
WEDNESDAY MORNING AND THE TRAILING PORTION DEEPENING IN CLOSER
PROXIMITY TO THE UPPER LOW CENTER NEAR THE 4-CORNERS AREA. A COLD
FRONT ASSOCIATED WITH THE LEAD LOW PUSHES THROUGH THE FORECAST
AREA DURING THE DAY ON WEDNESDAY AND KEEPS HIGH TEMPERATURES 30
DEGREES COOLER OR MORE FROM TUESDAY/S HIGHS. VERY LITTLE IF ANY
PRECIPITATION IS EXPECTED WITH THIS FRONT AS IT SWEEPS THROUGH THE
REGION AS THE AIRMASS STILL REMAINS RELATIVELY DRY ALOFT AND THE
MAIN DYNAMICS WITH THE UPPER LOW CENTER ARE STILL OFF TO THE WEST.
WEDNESDAY NIGHT THROUGH THURSDAY NIGHT WILL BRING THE POSSIBILITY
OF A WINTRY MIX OF PRECIPITATION AS THE NORTHERN BRANCH OF THE
UPPER PATTERN SWEEPS A TROUGH ACROSS THE NORTHERN PLAINS AND THE
UPPER LOW NEAR THE 4-CORNERS REGION CUTS OFF AND DRIFTS SLOWLY
OVER NEW MEXICO. THE SURFACE AREA OF LOWER PRESSURE CONSOLIDATES
INTO A SINGLE LOW IN THE VICINITY OF FAR WESTERN TEXAS ON THURSDAY
AND BEGINS TO ELONGATE ALONG THE SURFACE FRONTAL BOUNDARY
STRETCHING FROM WESTERN TEXAS INTO THE MID-MISSISSIPPI VALLEY
REGION. THE BEST CHANCES OF PRECIPITATION WILL BE ALONG THIS
FRONTAL BOUNDARY...WITH DIMINISHING CHANCES THE FURTHER NORTH ONE
TRAVELS AWAY FROM THE BOUNDARY. HAVE PLACED A MIX OF MAINLY LIGHT
RAIN AND SNOW ACROSS THE FORECAST AREA WITH GREATER PRECIPITATION
ACCUMULATIONS ACROSS THE SOUTHERN AREAS.
THE CUT OFF UPPER LOW LINGERS OVER NEW MEXICO FRIDAY AND FRIDAY
NIGHT AND THEN BEGINS TO LIFT OUT ACROSS THE CENTRAL AND SOUTHERN
PLAINS ON SATURDAY THROUGH SUNDAY NIGHT. MODEL SOLUTIONS OFFER A
VARIETY OF SOLUTIONS OF NOW AND WHEN THE UPPER LOW EVENTUALLY
TRACKS EAST OF THE ROCKIES...SO CONFIDENCE IN ANY ONE SOLUTION IS
MINIMAL AT THIS TIME. HAVE KEPT A SLIGHT CHANCE OF RAIN AND RAIN
AND SNOW ACROSS THE SOUTHERN AND EASTERN PORTIONS OF THE FORECAST
AREA DURING THIS TIME WITH A GENERAL RETURN OF TEMPERATURES TO
NEAR NORMAL.
WITH A SHORT WAVE RIDGE MOVING OVER THE AREA IN THE WAKE OF THE
UPPER LOW LIFTING THROUGH...HAVE KEPT THE EARLY PART OF NEXT WEEK
DRY WITH SLIGHTLY WARMER CONDITIONS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON)
ISSUED AT 1015 AM MST MON MAR 5 2012
VFR CONDITIONS EXPECTED THROUGH THE VALID PERIOD. TIGHT SURFACE
GRADIENT AHEAD OF LEE TROUGH IN EASTERN COLORADO HAS LEAD TO
GUSTS AROUND 25 MPH AT BOTH MCK AND GLD THIS MORNING...WHICH MAY
LINGER INTO THE EARLY TAF PERIOD. AS THE SURFACE TROUGH AXIS
SHIFTS EAST WINDS SHOULD DIMINISH SOME...WITH GUSTY CONDITIONS
COMING TO AN END AROUND SUNSET. WINDS WILL REMAIN OUT OF THE SOUTH
INITIALLY VEERING TO THE SOUTHWEST AND THEN WEST BEHIND THE TROUGH
AXIS. LEE TROUGH REDEVELOPS AND STRENGTHENS ON TUESDAY...WITH
WINDS SHIFTING BACK TO THE SOUTH. FOR NOW IT LOOKS LIKE GUSTY
WINDS WILL RE-DEVELOP AFTER THE END OF THE CURRENT VALID PERIOD
(18Z TUESDAY).
&&
.FIRE WEATHER...
ISSUED AT 1239 AM MST MON MAR 5 2012
MUCH ABOVE NORMAL TEMPERATURES COMBINED WITH GUSTY SOUTHERLY WINDS
WILL CREATE CRITICAL FIRE WEATHER CONDITIONS TODAY ALONG AND EAST
OF A TRIBUNE TO NORTON LINE IN NORTHWEST KANSAS DURING THE LATE
MORNING TO EARLY AFTERNOON HOURS. CRITICAL FIRE WEATHER CONDITIONS
ARE ALSO POSSIBLE ON TUESDAY IN MUCH OF THE AREA AS WINDY AND WARM
CONDITIONS CONTINUE.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
CO...FIRE WEATHER WATCH FROM TUESDAY MORNING THROUGH TUESDAY EVENING
FOR COZ252>254.
RED FLAG WARNING UNTIL 5 PM MST THIS AFTERNOON FOR COZ253-254.
KS...FIRE WEATHER WATCH FROM TUESDAY MORNING THROUGH TUESDAY EVENING
FOR KSZ001>004-013>016-027>029-041-042.
RED FLAG WARNING UNTIL 5 PM MST /6 PM CST/ THIS AFTERNOON FOR
KSZ003-004-013>016-027>029-041-042.
WIND ADVISORY UNTIL 5 PM MST /6 PM CST/ THIS AFTERNOON FOR
KSZ003-004-014>016-027>029-041-042.
NE...FIRE WEATHER WATCH FROM TUESDAY MORNING THROUGH TUESDAY EVENING
FOR NEZ079>081.
&&
$$
UPDATE...DR
SHORT TERM...DR
LONG TERM....LOCKHART
AVIATION...DR
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
531 AM CST MON MAR 5 2012
...UPDATED AVIATION SECTION FOR 12Z TAFS...
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 400 AM CST MON MAR 5 2012
TODAY:
FIRE WEATHER AND WINDS ARE THE MAIN CONCERNS DURING THE SHORT TERM PERIOD.
EXTENSIVE ANALYSIS OF FORECAST SOUNDINGS AND MOS GUIDANCE STILL SUPPORT
A WIND ADVISORY ACROSS WESTERN KANSAS. THE ATMOSPHERE WILL BECOME WELL
MIXED TO ABOUT 600 HPA WEST, 665 HPA WEST CENTRAL, 700 HPA CENTRAL.
WITHIN THIS LAYER, 30 TO 40 KT WINDS ARE EXPECTED. THE 0 TO 1 KM WIND
AVERAGE SHOWS THE STRONGEST AXIS ACROSS WESTERN KANSAS. FURTHER EAST,
THE EVENT LOOKS TO BE MORE MARGINAL. AS A RESULT, HAVE MADE A FEW ADJUSTMENTS
TO THE ONGOING WIND ADVISORY. MOS GUIDANCE ALSO SUPPORTS AREAS WEST
OF DODGE CITY SEEING ADVISORY LEVEL WIND SPEEDS. THE NAM HAD LOWER WIND
SPEEDS THAN COMPARED TO THE RUC AND GFS NEAR SURFACE. THE NAM MODEL
SOUNDING SHOWED THAT THERE IS NOT A SUPERADIABATIC LAYER NEAR THE SURFACE,
WHICH SEEMS UNLIKELY GIVEN THE STRONG INSOLATION/HEATING WE WILL SEE TODAY.
SPEAKING OF WHICH, TEMPERATURES TODAY WILL BE WELL ABOVE NORMAL WITH
MID 70S DEG F OUT WEST AND UPPER 60S TO AROUND 70 DEG F ACROSS SOUTH
CENTRAL KANSAS. WINDS WILL SUBSIDE NEAR SUNSET. PRECIPITABLE WATER VALUES
ARE FORECAST TO BE AROUND .30 SO THE ATMOSPHERE WILL BE VERY DRY AND
MAINLY CLOUD FREE THROUGHOUT THE DAY.
THE SECOND CONCERN IS FIRE WEATHER. HAVE RELIED MORE HEAVILY ON CONSRAW/CONSMOS
FOR DEWPOINT OUTPUT AS BOISE VERIFICATION SHOWS FAIRLY DECENT VERIFICATION
SCORES THAN COMPARED TO OTHER MODELS. DEWPOINTS IN THE LOW 20S DEG F
AND TEMPERATURES IN THE 70S WILL PROMOTE RH`S IN THE LOW TEENS. MORE
SPECIFIC INFORMATION CAN BE FOUND IN THE FIRE WEATHER SECTION BELOW.
TONIGHT:
WINDS WILL SUBSIDE BELOW ADVISORY LEVELS TOWARDS 00Z. I HAVE WARMED
MINIMUM TEMPERATURES FROM THE PREVIOUS FORECAST AS TONIGHTS LOWS LOOK
TO BE QUITE MILD...PARTICULARLY AT KP28. SOUTH CENTRAL KANSAS COULD
SEE LOWS ONLY AROUND 50 DEG F. FURTHER NORTHWEST, 40S DEG F ARE EXPECTED.
THESE MILD OVERNIGHT LOWS ARE IN RESPONSE TO A CONTINUED 5 TO 10 KT
S/SW WIND THROUGH THE OVERNIGHT PERIOD. THESE WINDS SHOULD KEEP TEMPERATURES
FROM FALLING THAT MUCH. BELIEVE THE 00Z NAM IS TOO COLD WITH THE LOWS
(UPPER 20S DEG F ACROSS WEST CENTRAL KANSAS VERSUS UPPER 30S TO LOWER
40S DEG F FROM THE GFS/ECMWF/GEM).
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 400 AM CST MON MAR 5 2012
TUESDAY AND TUESDAY NIGHT:
NOT MUCH WAS CHANGED TO THE FORECAST TUESDAY AND TUESDAY NIGHT...HOWEVER
DID LOWER THE FORECAST HIGHS A DEGREE OR TWO IN THE CENTRAL AND EAST
GIVEN MIXING HEIGHTS A BIT LOWER THAN FARTHER WEST AND SOME CIRRUS
CLOUD COVER MOVING ACROSS THE AREA. A DEEP LEE TROUGH WILL REMAIN IN
PLACE THROUGH THE AFTERNOON RESULTING IN STRONG SOUTH WINDS ESPECIALLY
ACROSS CENTRAL/EASTERN ZONES...PROBABLY MEETING/EXCEEDING WIND ADVISORY
CRITERIA ONCE AGAIN DURING THE MID TO LATE AFTERNOON HOURS. BREEZY SOUTH
WINDS WILL REMAIN THROUGH THE MAJORITY OF THE NIGHT KEEPING TEMPERATURES
RATHER WARM IN THE UPPER 40S TO LOWER 50S. BY 12Z WEDNESDAY...A STRONG
COLD FRONT WILL BE KNOCKING ON THE DOOR OF SOUTHWEST KANSAS...AS DISCUSSED
IN MORE DETAIL BELOW.
WEDNESDAY THROUGH THURSDAY:
THERE ARE ALL SORTS OF FORECAST CHALLENGES DURING THIS TIME FRAME...INCLUDING
THE POSSIBILITY OF SUBSTANTIAL WINTER PRECIPITATION (INCLUDING ICE).
WEDNESDAY WILL START OF RATHER MILD WITH SOUTH WINDS KEEPING TEMPERATURES
UP IN THE 50S DURING THE MORNING HOURS OVER MUCH OF THE FORECAST AREA.
AWAITING UPSTREAM HOWEVER...IS THE COLD CANADIAN AIRMASS...AND IT WILL
NOT TAKE ITS TIME TO RUSH SOUTH INTO SOUTHWESTERN KANSAS. THE OFFICIAL
FORECAST WILL REFLECT TEMPERATURES FALLING INTO THE 40S DURING THE AFTERNOON
...WITH MID TO UPPER 30S BY SUNSET OVER MUCH OF THE FORECAST AREA. MEANWHILE
...A SLOW MOVING UPPER LOW WILL BE CENTERED OVER NORTHERN ARIZONA WITH
A DEEP MOIST AIRMASS MAKING ITS WAY NORTH-NORTHWESTWARD THROUGH WEST
TEXAS AHEAD OF THE COLD FRONT. SYNOPTICALLY...THIS IS SHAPING UP TO
BE A CLASSIC CONVERGENCE OF WARM/MOIST AIR WITH SHALLOW (MODIFIED) ARCTIC
AIR RIGHT OVER SOUTHWESTERN KANSAS BEGINNING WEDNESDAY NIGHT.
THE HUGE QUESTION IS HOW FAST TEMPERATURES WILL FALL BELOW 32 DEGREES
AT THE SURFACE. DESPITE IT BEING 72 HOURS OUT...THE NAM AND SREF MEANS
DO PAINT AN OMINOUS PICTURE WHICH MATCHES CLOSELY THE ECMWF IN THE SURFACE
FEATURES (OWING TO HIGHER CONFIDENCE IN THE HIGHER RESOLUTION NAM/SREF
PROGS)...WITH TEMPERATURES FALLING TO 30-32 SOMETIME DURING THE LATE
EVENING HOURS WEDNESDAY. IMMEDIATELY SOUTH IN THE 900-800MB LAYER OFF
THE SURFACE...DEWPOINT TEMPERATURES WILL BE 9-12 DEGC AND SCATTERED/NUMEROUS
SHOWERS AND THUNDERSTORMS WILL DEVELOP ALONG AND NORTH OF THE FRONT
AT THE SURFACE. THESE SHOWERS AND STORMS WILL SPREAD NORTHWARD INTO
THE COLD SURFACE AIRMASS WHERE TEMPERATURES AT THE SURFACE WILL BE FALLING
DOWN TO (AND SLIGHTLY BELOW) FREEZING. A FAIRLY ROBUST WARM LAYER ALOFT
WILL BE LIKELY SUPPORTING FREEZING RAIN AS THE PRIMARY PRECIPITATION
TYPE BY EARLY INDICATIONS OFF THE NAM/SREF MEANS AS WELL AS THE ECMWF.
IN THE GRIDS...HAVE TRIED TO REFLECT THE PRECIPITATION TYPE AS SNOW/SLEET
IN THE NORTHWEST SLEET/FREEZING RAIN ACROSS THE BULK OF THE FORECAST
AREA AND FREEZING RAIN OR RAIN IN THE SOUTHEAST BY EARLY THURSDAY MORNING.
THE INITIAL WAVE OF PRECIPITATION WILL MOVE NORTHWARD DURING THE DAY
THURSDAY WITH PERHAPS A LULL IN PRECIPITATION. THAT BEING SAID...LOW
LEVEL FRONTOGENESIS WILL LIKELY STILL BE ONGOING WITH SURFACE TEMPERATURES
PRECARIOUSLY CLOSE TO 32F PRETTY MUCH ALL DAY. THE UPSHOT IS THAT SIGNIFICANT
ICING IS NOW CERTAINLY A HUGE CONCERN WITH THIS STORM GIVEN THE LATEST
MODEL GUIDANCE ON THE WHOLE.
THURSDAY NIGHT AND BEYOND:
BY LATE THURSDAY/THURSDAY NIGHT...THE ECMWF MODEL SHOWS THE CENTER OF
THE UPPER LOW STILL OVER WESTERN NEW MEXICO AND ANOTHER LOBE OF POTENTIAL
VORTICITY ROTATING AROUND THE LOW THURSDAY NIGHT...SETTING THE STAGE
FOR WHAT COULD BE ROUND 2 FRIDAY. THE NEAR-SURFACE ATMOSPHERE WILL MODIFY
SOME...BUT PROBABLY NOT ENOUGH TO KEEP WINTER PRECIPITATION OUT OF THE
FORECAST. SLIGHT CHANCE/CHANCE POPS WILL BE IN THE FORECAST THROUGH
SATURDAY...WHEN THE ECMWF FINALLY SHOWS THE UPPER LOW EJECTING NORTHEASTWARD.
THE ALLBLEND GUIDANCE WAS USED AND ONLY VERY SLIGHTLY MODIFIED FOR
THIS TIME FRAME.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING)
ISSUED AT 528 AM CST MON MAR 5 2012
UNDER A BROAD RIDGE OF HIGH PRESSURE IN THE ATMOSPHERE...DRY
CONDITIONS WILL PREVAIL RESULTING IN CONTINUED VFR CONDITIONS
THROUGH 12Z TUESDAY. STRONG SOUTHWEST WINDS WILL BE THE MAIN
CONCERN WITH FREQUENT GUSTS THIS AFTERNOON IN THE 30 TO 35 KT
RANGE. WINDS WILL WEAKEN AFTER SUNSET...BUT 12 TO 15 KT WIND
SHOULD CONTINUE THROUGH THE NIGHT TONIGHT.
&&
.FIRE WEATHER...
ISSUED AT 400 AM CST MON MAR 5 2012
CRITICAL FIRE WEATHER CONDITIONS (I.E. RED FLAG WARNING CRITERIA) IS
EXPECTED TODAY AND TOMORROW. HAVE ADJUSTED THE RFW FURTHER WEST AS EASTERN
COUNTIES ARE NOT EXPECTED TO MEET THE 15 PERCENT RELATIVE HUMIDITY CRITERIA
PER NAM/RUC OUTPUT. HAVE LEFT THE FIRE WEATHER WATCH ALONE FOR TUESDAY,
ALTHOUGH WITH EVEN WARMER TEMPERATURES AND CONTINUED LEE SURFACE TROUGHING
(AND RELATED SOUTHERLY WINDS), IT LOOKS LIKE TOMORROW WILL NEED ANOTHER
RED FLAG WARNING AS WELL. THOUGHT IT WAS BEST TO NOT HAVE TWO RFW`S
OUT SIMULTANEOUSLY TO AVOID CONFUSION.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 71 44 76 47 / 0 0 0 0
GCK 73 40 80 44 / 0 0 0 10
EHA 75 44 79 44 / 0 0 0 0
LBL 74 42 80 46 / 0 0 0 0
HYS 70 43 75 47 / 0 0 0 10
P28 70 49 72 52 / 0 0 0 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM NOON CST /11 AM MST/ TODAY TO 6 PM CST /5
PM MST/ THIS EVENING FOR KSZ043-044-061>063-074>077-084>087.
WIND ADVISORY FROM 10 AM CST /9 AM MST/ THIS MORNING TO 6 PM CST
/5 PM MST/ THIS EVENING FOR KSZ030-043>045-061>064-074>078-
084>088.
FIRE WEATHER WATCH TUESDAY AFTERNOON FOR KSZ043-061>063-074>076-
084>086.
&&
$$
SYNOPSIS...SUGDEN
SHORT TERM...SUGDEN
LONG TERM....UMSCHEID
AVIATION...UMSCHEID
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
400 AM CST MON MAR 5 2012
...UPDATED SYNOPSIS...SHORT TERM...LONG TERM...AND FIRE WEATHER SECTIONS...
.SYNOPSIS...
ISSUED AT 400 AM CST MON MAR 5 2012
A HIGHLY AMPLIFIED UPPER AIR PATTERN WAS OBSERVED ACROSS THE RAOB NETWORK
WITH A RIDGE OUT WEST AND A TROUGH OUT EAST. AN ANTICYCLONICALLY CURVED
135 KT 250 HPA JET EXTENDED ACROSS THE CANADIAN PRAIRIES AND INTO THE
NORTHERN PLAINS. A VERY INTENSE 180 KT 250 HPA JET WAS PUSHING NORTHEAST
ACROSS THE NEW YORK BIGHT AND INTO NORTHERN NEW ENGLAND. THE 500 HPA
GEOPOTENTIAL HEIGHT PATTERN ECHOED THE SAME PATTERN ABOVE EXCEPT WITH
A FEW MORE SHORTWAVE TROUGHS EVIDENT ACROSS THE NORTHEAST PACIFIC AND
ALSO ACROSS THE OHIO RIVER VALLEY. THE 500 HPA COLD POOL OF AT LEAST
-38 DEG C EXTENDED FROM ALBERTA AND INTO THE UPPER GREAT LAKES. WARMING
OF 700 AND 850 HPA TEMPERATURES WERE SEEN ACROSS THE HIGH PLAINS IN
RESPONSE TO UPPER LEVEL RIDGING, PARTICULARLY AT KDDC. AT THE SURFACE,
A LEE SFC TROUGH WAS STRENGTHENING ACROSS EASTERN COLORADO WITH HIGH
PRESSURE LOCATED ACROSS EASTERN KANSAS. AS A RESULT, SOUTHEASTERLY WINDS
WERE OCCURRING ACROSS WESTERN KANSAS AS OF 09Z.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 400 AM CST MON MAR 5 2012
TODAY:
FIRE WEATHER AND WINDS ARE THE MAIN CONCERNS DURING THE SHORT TERM PERIOD.
EXTENSIVE ANALYSIS OF FORECAST SOUNDINGS AND MOS GUIDANCE STILL SUPPORT
A WIND ADVISORY ACROSS WESTERN KANSAS. THE ATMOSPHERE WILL BECOME WELL
MIXED TO ABOUT 600 HPA WEST, 665 HPA WEST CENTRAL, 700 HPA CENTRAL.
WITHIN THIS LAYER, 30 TO 40 KT WINDS ARE EXPECTED. THE 0 TO 1 KM WIND
AVERAGE SHOWS THE STRONGEST AXIS ACROSS WESTERN KANSAS. FURTHER EAST,
THE EVENT LOOKS TO BE MORE MARGINAL. AS A RESULT, HAVE MADE A FEW ADJUSTMENTS
TO THE ONGOING WIND ADVISORY. MOS GUIDANCE ALSO SUPPORTS AREAS WEST
OF DODGE CITY SEEING ADVISORY LEVEL WIND SPEEDS. THE NAM HAD LOWER WIND
SPEEDS THAN COMPARED TO THE RUC AND GFS NEAR SURFACE. THE NAM MODEL
SOUNDING SHOWED THAT THERE IS NOT A SUPERADIABATIC LAYER NEAR THE SURFACE,
WHICH SEEMS UNLIKELY GIVEN THE STRONG INSOLATION/HEATING WE WILL SEE TODAY.
SPEAKING OF WHICH, TEMPERATURES TODAY WILL BE WELL ABOVE NORMAL WITH
MID 70S DEG F OUT WEST AND UPPER 60S TO AROUND 70 DEG F ACROSS SOUTH
CENTRAL KANSAS. WINDS WILL SUBSIDE NEAR SUNSET. PRECIPITABLE WATER VALUES
ARE FORECAST TO BE AROUND .30 SO THE ATMOSPHERE WILL BE VERY DRY AND
MAINLY CLOUD FREE THROUGHOUT THE DAY.
THE SECOND CONCERN IS FIRE WEATHER. HAVE RELIED MORE HEAVILY ON CONSRAW/CONSMOS
FOR DEWPOINT OUTPUT AS BOISE VERIFICATION SHOWS FAIRLY DECENT VERIFICATION
SCORES THAN COMPARED TO OTHER MODELS. DEWPOINTS IN THE LOW 20S DEG F
AND TEMPERATURES IN THE 70S WILL PROMOTE RH`S IN THE LOW TEENS. MORE
SPECIFIC INFORMATION CAN BE FOUND IN THE FIRE WEATHER SECTION BELOW.
TONIGHT:
WINDS WILL SUBSIDE BELOW ADVISORY LEVELS TOWARDS 00Z. I HAVE WARMED
MINIMUM TEMPERATURES FROM THE PREVIOUS FORECAST AS TONIGHTS LOWS LOOK
TO BE QUITE MILD...PARTICULARLY AT KP28. SOUTH CENTRAL KANSAS COULD
SEE LOWS ONLY AROUND 50 DEG F. FURTHER NORTHWEST, 40S DEG F ARE EXPECTED.
THESE MILD OVERNIGHT LOWS ARE IN RESPONSE TO A CONTINUED 5 TO 10 KT
S/SW WIND THROUGH THE OVERNIGHT PERIOD. THESE WINDS SHOULD KEEP TEMPERATURES
FROM FALLING THAT MUCH. BELIEVE THE 00Z NAM IS TOO COLD WITH THE LOWS
(UPPER 20S DEG F ACROSS WEST CENTRAL KANSAS VERSUS UPPER 30S TO LOWER
40S DEG F FROM THE GFS/ECMWF/GEM).
.LONG TERM...(TUESDAY THROUGH SUNDAY)
ISSUED AT 400 AM CST MON MAR 5 2012
TUESDAY AND TUESDAY NIGHT:
NOT MUCH WAS CHANGED TO THE FORECAST TUESDAY AND TUESDAY NIGHT...HOWEVER
DID LOWER THE FORECAST HIGHS A DEGREE OR TWO IN THE CENTRAL AND EAST
GIVEN MIXING HEIGHTS A BIT LOWER THAN FARTHER WEST AND SOME CIRRUS
CLOUD COVER MOVING ACROSS THE AREA. A DEEP LEE TROUGH WILL REMAIN IN
PLACE THROUGH THE AFTERNOON RESULTING IN STRONG SOUTH WINDS ESPECIALLY
ACROSS CENTRAL/EASTERN ZONES...PROBABLY MEETING/EXCEEDING WIND ADVISORY
CRITERIA ONCE AGAIN DURING THE MID TO LATE AFTERNOON HOURS. BREEZY SOUTH
WINDS WILL REMAIN THROUGH THE MAJORITY OF THE NIGHT KEEPING TEMPERATURES
RATHER WARM IN THE UPPER 40S TO LOWER 50S. BY 12Z WEDNESDAY...A STRONG
COLD FRONT WILL BE KNOCKING ON THE DOOR OF SOUTHWEST KANSAS...AS DISCUSSED
IN MORE DETAIL BELOW.
WEDNESDAY THROUGH THURSDAY:
THERE ARE ALL SORTS OF FORECAST CHALLENGES DURING THIS TIME FRAME...INCLUDING
THE POSSIBILITY OF SUBSTANTIAL WINTER PRECIPITATION (INCLUDING ICE).
WEDNESDAY WILL START OF RATHER MILD WITH SOUTH WINDS KEEPING TEMPERATURES
UP IN THE 50S DURING THE MORNING HOURS OVER MUCH OF THE FORECAST AREA.
AWAITING UPSTREAM HOWEVER...IS THE COLD CANADIAN AIRMASS...AND IT WILL
NOT TAKE ITS TIME TO RUSH SOUTH INTO SOUTHWESTERN KANSAS. THE OFFICIAL
FORECAST WILL REFLECT TEMPERATURES FALLING INTO THE 40S DURING THE AFTERNOON
...WITH MID TO UPPER 30S BY SUNSET OVER MUCH OF THE FORECAST AREA. MEANWHILE
...A SLOW MOVING UPPER LOW WILL BE CENTERED OVER NORTHERN ARIZONA WITH
A DEEP MOIST AIRMASS MAKING ITS WAY NORTH-NORTHWESTWARD THROUGH WEST
TEXAS AHEAD OF THE COLD FRONT. SYNOPTICALLY...THIS IS SHAPING UP TO
BE A CLASSIC CONVERGENCE OF WARM/MOIST AIR WITH SHALLOW (MODIFIED) ARCTIC
AIR RIGHT OVER SOUTHWESTERN KANSAS BEGINNING WEDNESDAY NIGHT.
THE HUGE QUESTION IS HOW FAST TEMPERATURES WILL FALL BELOW 32 DEGREES
AT THE SURFACE. DESPITE IT BEING 72 HOURS OUT...THE NAM AND SREF MEANS
DO PAINT AN OMINOUS PICTURE WHICH MATCHES CLOSELY THE ECMWF IN THE SURFACE
FEATURES (OWING TO HIGHER CONFIDENCE IN THE HIGHER RESOLUTION NAM/SREF
PROGS)...WITH TEMPERATURES FALLING TO 30-32 SOMETIME DURING THE LATE
EVENING HOURS WEDNESDAY. IMMEDIATELY SOUTH IN THE 900-800MB LAYER OFF
THE SURFACE...DEWPOINT TEMPERATURES WILL BE 9-12 DEGC AND SCATTERED/NUMEROUS
SHOWERS AND THUNDERSTORMS WILL DEVELOP ALONG AND NORTH OF THE FRONT
AT THE SURFACE. THESE SHOWERS AND STORMS WILL SPREAD NORTHWARD INTO
THE COLD SURFACE AIRMASS WHERE TEMPERATURES AT THE SURFACE WILL BE FALLING
DOWN TO (AND SLIGHTLY BELOW) FREEZING. A FAIRLY ROBUST WARM LAYER ALOFT
WILL BE LIKELY SUPPORTING FREEZING RAIN AS THE PRIMARY PRECIPITATION
TYPE BY EARLY INDICATIONS OFF THE NAM/SREF MEANS AS WELL AS THE ECMWF.
IN THE GRIDS...HAVE TRIED TO REFLECT THE PRECIPITATION TYPE AS SNOW/SLEET
IN THE NORTHWEST SLEET/FREEZING RAIN ACROSS THE BULK OF THE FORECAST
AREA AND FREEZING RAIN OR RAIN IN THE SOUTHEAST BY EARLY THURSDAY MORNING.
THE INITIAL WAVE OF PRECIPITATION WILL MOVE NORTHWARD DURING THE DAY
THURSDAY WITH PERHAPS A LULL IN PRECIPITATION. THAT BEING SAID...LOW
LEVEL FRONTOGENESIS WILL LIKELY STILL BE ONGOING WITH SURFACE TEMPERATURES
PRECARIOUSLY CLOSE TO 32F PRETTY MUCH ALL DAY. THE UPSHOT IS THAT SIGNIFICANT
ICING IS NOW CERTAINLY A HUGE CONCERN WITH THIS STORM GIVEN THE LATEST
MODEL GUIDANCE ON THE WHOLE.
THURSDAY NIGHT AND BEYOND:
BY LATE THURSDAY/THURSDAY NIGHT...THE ECMWF MODEL SHOWS THE CENTER OF
THE UPPER LOW STILL OVER WESTERN NEW MEXICO AND ANOTHER LOBE OF POTENTIAL
VORTICITY ROTATING AROUND THE LOW THURSDAY NIGHT...SETTING THE STAGE
FOR WHAT COULD BE ROUND 2 FRIDAY. THE NEAR-SURFACE ATMOSPHERE WILL MODIFY
SOME...BUT PROBABLY NOT ENOUGH TO KEEP WINTER PRECIPITATION OUT OF THE
FORECAST. SLIGHT CHANCE/CHANCE POPS WILL BE IN THE FORECAST THROUGH
SATURDAY...WHEN THE ECMWF FINALLY SHOWS THE UPPER LOW EJECTING NORTHEASTWARD.
THE ALLBLEND GUIDANCE WAS USED AND ONLY VERY SLIGHTLY MODIFIED FOR
THIS TIME FRAME.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT)
ISSUED AT 1100 PM CST SUN MAR 4 2012
THE MAIN FOCUS FOR THE 06Z TAFS IS WINDS. TOMORROW LOOKS LIKE A VERY
WINDY DAY IN ASSOCIATION WITH A STRENGTHENING LEE SURFACE TROF ACROSS
WESTERN KANSAS. HIGH PRESSURE WILL SLIDE TO THE SE THROUGH THE OVERNIGHT
WITH SOUTHEASTERLY TO SOUTHERLY WINDS INCREASING THROUGH MORNING. BY
NOON WINDS WILL VEER TO THE S/SSW AS THE LEE TROUGH MOVES EAST. WINDS
OF 25 TO 30 KT WITH GUSTS TO 35 TO 40 KT ARE EXPECTED TOMORROW. WINDS
WILL SUBSIDE BY SUNSET. VFR CIGS WILL PREVAIL THROUGH THE PD.
&&
.FIRE WEATHER...
ISSUED AT 400 AM CST MON MAR 5 2012
CRITICAL FIRE WEATHER CONDITIONS (I.E. RED FLAG WARNING CRITERIA) IS
EXPECTED TODAY AND TOMORROW. HAVE ADJUSTED THE RFW FURTHER WEST AS EASTERN
COUNTIES ARE NOT EXPECTED TO MEET THE 15 PERCENT RELATIVE HUMIDITY CRITERIA
PER NAM/RUC OUTPUT. HAVE LEFT THE FIRE WEATHER WATCH ALONE FOR TUESDAY,
ALTHOUGH WITH EVEN WARMER TEMPERATURES AND CONTINUED LEE SURFACE TROUGHING
(AND RELATED SOUTHERLY WINDS), IT LOOKS LIKE TOMORROW WILL NEED ANOTHER
RED FLAG WARNING AS WELL. THOUGHT IT WAS BEST TO NOT HAVE TWO RFW`S
OUT SIMULTANEOUSLY TO AVOID CONFUSION.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 71 44 76 47 / 0 0 0 0
GCK 73 40 80 44 / 0 0 0 10
EHA 75 44 79 44 / 0 0 0 0
LBL 74 42 80 46 / 0 0 0 0
HYS 70 43 75 47 / 0 0 0 10
P28 70 49 72 52 / 0 0 0 10
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
RED FLAG WARNING FROM NOON CST /11 AM MST/ TODAY TO 6 PM CST /5
PM MST/ THIS EVENING FOR KSZ043-044-061>063-074>077-084>087.
WIND ADVISORY FROM 10 AM CST /9 AM MST/ THIS MORNING TO 6 PM CST
/5 PM MST/ THIS EVENING FOR KSZ030-043>045-061>064-074>078-
084>088.
FIRE WEATHER WATCH TUESDAY AFTERNOON FOR KSZ043-061>063-074>076-
084>086.
&&
$$
SYNOPSIS...SUGDEN
SHORT TERM...SUGDEN
LONG TERM....UMSCHEID
AVIATION...SUGDEN
FIRE WEATHER...SUGDEN
AREA FORECAST DISCUSSION...UPDATED
NWS GRAY ME
721 AM EST MON MAR 5 2012
.SYNOPSIS...
A TROUGH OF LOW PRESSURE WILL PUSH OFFSHORE TODAY AS HIGH PRESSURE
BUILDS IN FROM THE WEST. HIGH PRESSURE WILL CREST OVER NORTHERN
NEW ENGLAND LATE TUESDAY NIGHT WITH A WARM FRONT MOVING IN FROM
THE SOUTHWEST. MUCH WARMER WEATHER IS EXPECTED FOR WEDNESDAY AND
THURSDAY. A COLD FRONT WILL MOVE THROUGH THE AREA THURSDAY NIGHT
INTO FRIDAY MORNING... BRINGING COOLER CONDITIONS BACK TO THE
REGION AS WELL AS A CHANCE FOR SHOWERS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
COLD FRONT HAS PUSHED WELL OFFSHORE WITH SURFACE TROUGH AND UPPER
LEVEL FRONTOGENESIS HELPING TO KEEP SNOW SHOWERS GOING ACROSS THE
AREA. THE MAIN AREA OF SNOW WAS NOW LOCATED OVER SKOWHEGAN AND
AUGUSTA AND MOVING STEADILY EAST. LATEST HRRR SUGGESTS THESE
ECHOES WILL DIMINISH OVER THE NEXT COUPLE OF HOURS. HIGHER DBZ
ECHOES HAVE ALSO DISAPPEARED. ANOTHER AREA OF UPSLOPE SNOW SHOWERS
OVER THE NH MOUNTAINS IS BEING ENHANCED BY AN AREA OF 800MB
FRONTOGENESIS AND WILL WEAKEN LATER THIS MORNING AS THE FRONTAL
FORCING MOVES AWAY. OVERALL ONLY EXPECTING ANOTHER 0.5-1.0" OF
SNOW. THE LOW PRESSURE SYSTEM WILL BE SUPPRESSED TOWARDS THE
CANADIAN MARITIMES TODAY AS HIGH PRESSURE BUILDS IN FROM THE WEST.
COLD AIR ADVECTION WILL KEEP HIGH TEMPERATURES TODAY IN THE UPPER
TEENS AND LOWER 20S NORTH TO UPPER 20S AND LOWER 30S SOUTH.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
EXPECTING A CHILLY NIGHT TONIGHT AS DENSE HIGH PRESSURE MOVES IN
FROM THE WEST AND ALLOWS WINDS TO DIE DOWN AND SKIES TO CLEAR.
THIS WILL RESULT IN GOOD RADIATIONAL COOLING CONDITIONS WITH PW
VALUES AROUND 0.10". WENT CLOSE TO NAM12 VALUES FOR LOW
TEMPERATURES WHICH GIVES ZERO TO JUST BELOW ZERO READINGS ACROSS
THE NORTH AND SINGLE DIGITS ACROSS THE INTERIOR. THE COAST WILL BE
A BIT WARMER WITH LOWS AROUND 10 DEGREES F.
HIGH PRESSURE WILL BE DIRECTLY CENTERED OVER THE REGION ON TUESDAY
RESULTING IN LIGHT AND VARIABLE WINDS. HIGH TEMPERATURES WILL BE
SLIGHTLY WARMER BUT WE WILL SEE INCREASING CLOUDINESS AS SHORT
WAVE ENERGY WORKS ITS WAY THROUGH RIDGING ALOFT.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
A WARM FRONT PUSHES THROUGH THE REGION FROM SOUTHWEST TO NORTHEAST
TUESDAY NIGHT... WITH SOUTHWESTERLY WINDS AND MUCH WARMER
TEMPERATURES BEHIND IT. THE WARMER WEATHER WILL OVERSPREAD THE
WHOLE AREA ON WEDNESDAY WITH HIGHS REACHING THE 40S AND 50S. BY
THURSDAY... HIGHS WILL REACH THE 50S AND EVEN LOW 60S IN SOUTHERN
AREAS WITH GUSTY SOUTHWEST WINDS.
A COLD FRONT PUSHES INTO NEW ENGLAND FROM THE NORTHWEST THURSDAY
NIGHT AND TO THE COAST BY FRIDAY MORNING. ALTHOUGH THE BEST
FORCING WITH THIS FRONT IS WELL TO THE NORTH... GOOD CONVERGENCE
AND DECENT MOISTURE AHEAD OF THE BOUNDARY WILL LIKELY LEAD TO SOME
RAIN SHOWERS ALONG AND AHEAD OF THE FRONT... AND MAYBE A FEW SNOW
SHOWERS BEHIND IT. BY FRIDAY... COLDER AIR WILL BE MOVING IN ON
NORTHWEST WINDS WITH HIGH TEMPERATURES BACK DOWN INTO THE 30S OR
LOW 40S. THE COOLER WEATHER LASTS THROUGH THE WEEKEND AS HIGH
PRESSURE PUSHES THROUGH THE AREA.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
SHORT TERM...TAFS ARE VARIABLE THE NEXT FEW HOURS DUE TO SNOW
SHOWERS...HOWEVER THE SHOWERS SHOULD END BY DAYBREAK.
MVFR/MARGINAL VFR CEILINGS ARE LIKELY FOR MUCH OF THE DAY WITH
STRATUS IN THE AREA. WINDS MAY GUST INTO THE LOWER 20S ALONG THE
COAST.
LONG TERM...QUIET CONDITIONS EXPECTED WITH MAINLY VFR THROUGH MOST
OF THE WEEK. HOWEVER... SOME SHOWERS ALONG A FRONT ON THURSDAY
NIGHT MAY BRING MVFR CONDITIONS. VFR RETURN FRIDAY INTO THE WEEKEND.
&&
.MARINE...
SHORT TERM...SMALL CRAFT ADVISORY CONTINUES. ALTHOUGH CONDITIONS
ARE CURRENTLY BELOW CRITERIA WAVES AND WIND GUSTS SHOULD INCREASE
AS COLD AIR ADVECTION CONTINUES THROUGHOUT THE DAY.
LONG TERM...GENERALLY QUIET... HOWEVER SOUTHWEST FLOW ON THURSDAY
MAY INCREASE INTO SMALL CRAFT ADVISORY LEVELS WITH GUSTS TO 25 OR
30 KT.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST TUESDAY FOR ANZ150-152-154.
&&
$$
UPDATE...HANES
AREA FORECAST DISCUSSION
NWS GRAY ME
248 AM EST MON MAR 5 2012
.SYNOPSIS...
A TROUGH OF LOW PRESSURE WILL PUSH OFFSHORE TODAY AS HIGH PRESSURE
BUILDS IN FROM THE WEST. HIGH PRESSURE WILL CREST OVER NORTHERN
NEW ENGLAND LATE TUESDAY NIGHT WITH A WARM FRONT MOVING IN FROM
THE SOUTHWEST. MUCH WARMER WEATHER IS EXPECTED FOR WEDNESDAY AND
THURSDAY. A COLD FRONT WILL MOVE THROUGH THE AREA THURSDAY NIGHT
INTO FRIDAY MORNING... BRINGING COOLER CONDITIONS BACK TO THE
REGION AS WELL AS A CHANCE FOR SHOWERS.
&&
.NEAR TERM /THROUGH TODAY/...
COLD FRONT HAS PUSHED WELL OFFSHORE WITH SURFACE TROUGH AND UPPER
LEVEL FRONTOGENESIS HELPING TO KEEP SNOW SHOWERS GOING ACROSS THE
AREA. THE MAIN AREA OF SNOW WAS NOW LOCATED OVER SKOWHEGAN AND
AUGUSTA AND MOVING STEADILY EAST. LATEST HRRR SUGGESTS THESE
ECHOES WILL DIMINISH OVER THE NEXT COUPLE OF HOURS. HIGHER DBZ
ECHOES HAVE ALSO DISAPPEARED. ANOTHER AREA OF UPSLOPE SNOW SHOWERS
OVER THE NH MOUNTAINS IS BEING ENHANCED BY AN AREA OF 800MB
FRONTOGENESIS AND WILL WEAKEN LATER THIS MORNING AS THE FRONTAL
FORCING MOVES AWAY. OVERALL ONLY EXPECTING ANOTHER 0.5-1.0" OF
SNOW. THE LOW PRESSURE SYSTEM WILL BE SUPPRESSED TOWARDS THE
CANADIAN MARITIMES TODAY AS HIGH PRESSURE BUILDS IN FROM THE WEST.
COLD AIR ADVECTION WILL KEEP HIGH TEMPERATURES TODAY IN THE UPPER
TEENS AND LOWER 20S NORTH TO UPPER 20S AND LOWER 30S SOUTH.
&&
.SHORT TERM /TONIGHT AND TUESDAY/...
EXPECTING A CHILLY NIGHT TONIGHT AS DENSE HIGH PRESSURE MOVES IN
FROM THE WEST AND ALLOWS WINDS TO DIE DOWN AND SKIES TO CLEAR.
THIS WILL RESULT IN GOOD RADIATIONAL COOLING CONDITIONS WITH PW
VALUES AROUND 0.10". WENT CLOSE TO NAM12 VALUES FOR LOW
TEMPERATURES WHICH GIVES ZERO TO JUST BELOW ZERO READINGS ACROSS
THE NORTH AND SINGLE DIGITS ACROSS THE INTERIOR. THE COAST WILL BE
A BIT WARMER WITH LOWS AROUND 10 DEGREES F.
HIGH PRESSURE WILL BE DIRECTLY CENTERED OVER THE REGION ON TUESDAY
RESULTING IN LIGHT AND VARIABLE WINDS. HIGH TEMPERATURES WILL BE
SLIGHTLY WARMER BUT WE WILL SEE INCREASING CLOUDINESS AS SHORT
WAVE ENERGY WORKS ITS WAY THROUGH RIDGING ALOFT.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
A WARM FRONT PUSHES THROUGH THE REGION FROM SOUTHWEST TO NORTHEAST
TUESDAY NIGHT... WITH SOUTHWESTERLY WINDS AND MUCH WARMER
TEMPERATURES BEHIND IT. THE WARMER WEATHER WILL OVERSPREAD THE
WHOLE AREA ON WEDNESDAY WITH HIGHS REACHING THE 40S AND 50S. BY
THURSDAY... HIGHS WILL REACH THE 50S AND EVEN LOW 60S IN SOUTHERN
AREAS WITH GUSTY SOUTHWEST WINDS.
A COLD FRONT PUSHES INTO NEW ENGLAND FROM THE NORTHWEST THURSDAY
NIGHT AND TO THE COAST BY FRIDAY MORNING. ALTHOUGH THE BEST
FORCING WITH THIS FRONT IS WELL TO THE NORTH... GOOD CONVERGENCE
AND DECENT MOISTURE AHEAD OF THE BOUNDARY WILL LIKELY LEAD TO SOME
RAIN SHOWERS ALONG AND AHEAD OF THE FRONT... AND MAYBE A FEW SNOW
SHOWERS BEHIND IT. BY FRIDAY... COLDER AIR WILL BE MOVING IN ON
NORTHWEST WINDS WITH HIGH TEMPERATURES BACK DOWN INTO THE 30S OR
LOW 40S. THE COOLER WEATHER LASTS THROUGH THE WEEKEND AS HIGH
PRESSURE PUSHES THROUGH THE AREA.
&&
.AVIATION /07Z MONDAY THROUGH FRIDAY/...
SHORT TERM...TAFS ARE VARIABLE THE NEXT FEW HOURS DUE TO SNOW
SHOWERS...HOWEVER THE SHOWERS SHOULD END BY DAYBREAK.
MVFR/MARGINAL VFR CEILINGS ARE LIKELY FOR MUCH OF THE DAY WITH
STRATUS IN THE AREA. WINDS MAY GUST INTO THE LOWER 20S ALONG THE
COAST.
LONG TERM...QUIET CONDITIONS EXPECTED WITH MAINLY VFR THROUGH MOST
OF THE WEEK. HOWEVER... SOME SHOWERS ALONG A FRONT ON THURSDAY
NIGHT MAY BRING MVFR CONDITIONS. VFR RETURN FRIDAY INTO THE WEEKEND.
&&
.MARINE...
SHORT TERM...SMALL CRAFT ADVISORY CONTINUES. ALTHOUGH CONDITIONS
ARE CURRENTLY BELOW CRITERIA WAVES AND WIND GUSTS SHOULD INCREASE
AS COLD AIR ADVECTION CONTINUES THROUGHOUT THE DAY.
LONG TERM...GENERALLY QUIET... HOWEVER SOUTHWEST FLOW ON THURSDAY
MAY INCREASE INTO SMALL CRAFT ADVISORY LEVELS WITH GUSTS TO 25 OR
30 KT.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST TUESDAY FOR ANZ150-152-154.
&&
$$
HANES/KIMBLE
AREA FORECAST DISCUSSION...UPDATED
NWS GRAY ME
1241 AM EST MON MAR 5 2012
.SYNOPSIS...
A TROUGH OF LOW PRESSURE WILL GRADUALLY GIVE WAY TO HIGH PRESSURE
BUILDING IN FROM THE WEST TODAY. HIGH PRESSURE WILL CREST OVER THE
REGION ON TUESDAY AND WILL HOLD OFF THE EAST COAST THROUGH
WEDNESDAY. A WEAK COLD FRONT WILL SLOWLY APPROACH FROM THE
NORTHWEST ON THURSDAY AND WILL PUSH SOUTH THROUGH THE REGION
THURSDAY EVENING. HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT
THURSDAY NIGHT...SHIFTING OFFSHORE FRIDAY AFTERNOON. A COLD FRONT
WILL DROP SOUTH FROM CANADA ON SATURDAY MOVING OFFSHORE BY LATE IN
THE DAY. HIGH PRESSURE WILL BUILD OVER NEW ENGLAND ON SUNDAY.
&&
.UPDATE...
MAIN AREA OF SNOW STILL DRIFTING ACROSS CENTRAL MAINE. TOTALS HAVE
AVERAGED A QUICK 0.5-1.00" BUT THANKFULLY THE PRECIP IS MOVING
STEADILY EAST. LATEST HRRR SUGGESTS THESE ECHOES WILL DIMINISH
OVER THE NEXT COUPLE OF HOURS. HIGHER DBZ ECHOES HAVE BEGUN TO
DISAPPEAR. ANOTHER AREA OF SNOW SHOWERS COMING OUT THE THE NH
MOUNTAINS IS BEING ENHANCED BY THE COLD FRONT AND WILL WEAKEN
LATER THIS MORNING AS THE FRONTAL FORCING MOVES AWAY. FOR THE
UPDATE ADJUST SNOW TOTALS SLIGHTLY AS WELL AS TEMPERATURES...DEW
POINTS...AND POPS.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
PREVIOUS DISCUSSION...BAND OF SNFL IS BECOMING MORE N-S ORIENTED
ATTM...AS SFC TROF CONTINUES TO SAG TOWARDS THE COAST. WILL
PROBABLY SEE SNFL RATES APPROACH 1"/HR IN THE HEAVIEST PART OF THE
BAND. IT IS ALSO BECOMING A LITTLE MORE PROGRESSIVE...SO 1-2"
TOTALS LOOK GOOD. MIGHT SEE SOME LOCALIZED HIGHER AMNTS. IF BAND
BEGINS TO SLOW DOWN AGAIN OR PERSIST LIKE THE HRRR SUGGESTS IT
MIGHT...QPF AND SNFL TOTALS WOULD NEED TO BE NUDGED UP SOME MORE
FOR THE MIDCOAST.
PREVIOUS DISCUSSION...INTERESTING SLOW MOVING BAND OF SHSN
MOVING ACROSS NRN NEW ENG IN ASSOC WITH COLD FRONT SETTLING
SOUTHWARD. VSBL SATELLITE IMAGES CONTINUES TO SHOW THE CONVECTIVE
LOOKING CLOUDS SHIFTING SLOWLY TO THE EAST. THIS EASTWARD
PROGRESSION HAS BEEN SLOWED THIS AFTERNOON BY THE PRESENCE OF
SUBSIDENCE AROUND THE PERIPHERY OF THE OFFSHORE COASTAL SYSTEM.
SR MODELS BRING THIS BOUNDARY TO SRN MAINE BY EVENING. THE LATEST
HRRR RUNS HAVE FINALLY BEGUN TO PICK UP THE BRIEF PERIOD OF BANDED
PCPN NOW FORECAST FOR THE LAST SVRL RUNS BY THE NAM (AND TO SOME
EXTENT THE GFS) TO SETTLE OVER SOUTH-CENTRAL PTNS OF OUR FORECAST
AREA THIS EVENING.
WITH A SFC LOW INTENSIFYING OFF THE CST...AND A STALLED OUT
BOUNDARY INTERACTING WITH POSITIVE VERTICAL MOTION IN THE LWR
LVLS...THIS PTTN IS BEGINNING TO RESEMBLE SOME CHARACTERISTICS OF
A NORLUN TYPE II TROUGH ("LDRI" FROM PREV NE STORM CONFERENCES).
WILL ENHANCE THE POPS FOR THIS EVENING OVER SOUTH-CENTRAL AND
COASTAL AREAS N OF PWM WHERE BEST LAPSE RATES AND MOISTURE
CONVERGENCE WILL EXIST. POPS WILL TAPER OFF AS YOU HEAD INTO WRN
AND SRN NH.
QPF...WILL INCLUDE A SNOW MAP FOR THIS AFTNS AND TNGTS TOTALS.
WILL BE UPDATING THIS GRAPHIC PERIODICALLY THRU THE EVE HRS.
OTRW...PLENTY OF CLOUDS OVERNIGHT WITH THE PASSAGE OF THE UPPER
TROF. MOST OF THE PCPN TO EXIT OFF THE COAST OR DIMINISH TOWARDS
MRNG.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 AM TUESDAY/...
BY MONDAY...ANY LEFTOVER FLURRIES WILL BE CONFINED TO THE UPSLOPE
AREAS OF THE HIGHER TERRAIN IN THE NRN/WRN MTNS. USED A BLEND OF
MET/MAV MOS FOR AFTN HIGH TEMPS. TEMPS TOMORROW WILL BE RUNNING
COOLER THAN WHAT WE HAVE BEEN USED TO AS THE CORE OF THE RIDGE
KEEPS H8 TEMPS BTWN -14 AND -18 DEG C.
CYCLOGENESIS OCCURS ONCE AGAIN MONDAY NIGHT WELL OFF THE NEW
ENGLAND COASTLINE. TOO FAR OFFSHORE TO INFLUENCE OUR WX IN ME AND NH.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
HIGH PRESSURE WILL BUILD OVER NEW ENGLAND ON TUESDAY BRINGING MOSTLY
SUNNY SKIES TO MUCH OF THE AREA. WILL LIKELY SEE SOME HIGH
CLOUDINESS SPILLING INTO WESTERN ZONES DURING THE AFTERNOON. HIGH
TEMPERATURES WILL REMAIN ON THE COOL SIDE WITH MID 20S TO LOWER 30S
IN THE NORTH AND LOWER TO MID 30S IN THE SOUTH.
RETURN FLOW WILL BRING WARMER AIR BACK INTO THE REGION TUESDAY NIGHT.
EXPECT VARIABLE CLOUDINESS AS AREA OF WEAK OVER-RUNNING SHIFTS INTO
THE AREA FROM THE WEST. COULD SEE A STRAY SNOW SHOWER IN THE NORTH
BUT NOT GOING WITH ANY POPS AT THIS POINT. LOOKING FOR MILDER
OVERNIGHT LOWS RANGING FROM THE LOWER TO MID TEENS IN THE NORTH
AND MID TEENS TO LOWER 20S IN THE SOUTH.
MOSTLY SUNNY WEATHER WILL CONTINUE ON WEDNESDAY AS HIGH PRESSURE
REMAINS ANCHORED OFF THE EAST COAST. ONLY LOOKING FOR A FEW PATCHY
HIGH CLOUDS WITH TEMPERATURES IN THE LOWER TO MID 40S IN THE NORTH
AND MID 40S TO LOWER 50S IN THE SOUTH.
WEAK COLD FRONT WILL SAG SOUTH FROM CANADA ON THURSDAY. SEEING SOME
RUN TO RUN TIMING DIFFERENCES ON HOW QUICKLY THIS BOUNDARY DROPS
SOUTH BUT IT SHOULD BE ANOTHER DRY AND MOSTLY SUNNY DAY IN AT LEAST
SOUTHERN ZONES. EXPECT CLOUDS TO INCREASE IN THE AFTERNOON ACROSS
THE NORTH WITH A CHANCE OF A LATE DAY SPRINKLE. HIGH TEMPERATURES
WILL AGAIN BE WELL ABOVE NORMAL WITH MID 40S TO LOWER 50S IN THE
NORTH AND RANGING THROUGH THE 50S TO NEAR 60 IN THE SOUTH.
COLD FRONT WILL PUSH SOUTH THROUGH THE REGION THURSDAY EVENING
..SHIFTING OFFSHORE BEFORE MIDNIGHT. WILL STICK WITH CHANCE POPS FOR
MUCH OF THE AREA WITH RAIN SHOWERS MIXING WITH OR CHANGING TO SNOW
SHOWERS BEFORE ENDING. SHOULD SEE CLEARING SKIES AFTER MIDNIGHT AS
HIGH PRESSURE QUICKLY BUILDS IN FROM THE WEST.
HIGH PRESSURE WILL CREST OVER THE REGION EARLY FRIDAY BEFORE MOVING
OFFSHORE. WARM FRONT CROSSING SOUTHERN CANADA WILL BRING HIGH CLOUDS
INTO THE REGION DURING THE LATE MORNING AND EARLY AFTERNOON BUT
LOOKING FOR A DRY DAY THROUGHOUT THE FORECAST AREA.
A WEAK COLD FRONT WILL DROP SOUTH FROM CANADA ON SATURDAY AND WILL
QUICKLY MOVE OFFSHORE IN THE AFTERNOON. LITTLE IF ANY MOISTURE OR
FORCING WITH THIS BOUNDARY SO AT THIS POINT SEE LITTLE MORE THAN A
FEW PASSING CLOUDS WITH THIS SYSTEM.
ANOTHER AREA OF HIGH PRESSURE WILL QUICKLY BUILD SOUTH FROM CANADA
SATURDAY NIGHT AND INTO SUNDAY KEEPING WEATHER MILD AND QUIET IN THE
NORTHEAST.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
SHORT TERM...MVFR AND LCLY IFR CONDS DVLPG THIS EVE...MAINLY OVER
S-CNTRL ME AND ALG THE MIDCOAST RGN. CONDS SLOWLY IMPROVG LATE
TNGT AND THROUGH MONDAY.
LONG TERM...VFR TUESDAY THROUGH THURSDAY. SOME AREAS OF MVFR
CEILINGS THURSDAY EVENING. VFR FRIDAY.
&&
.MARINE...
SHORT TERM...SCA HAS BEEN EXTENDED FOR THE OUTER WATERS. THERE
WILL BE A LULL IN THE WIND FIELD TNGT...HWVR...SEAS WILL RMN AOA 5
FT. NW GRADIENT TO INCREASE ONCE AGAIN ON MONDAY WITH FRQNT GUSTS
TO 25 KT CONTINUING RGT THRU MON NGT. HENCE SCAS HAVE BEEN
EXTENDED OUTWARDS IN TIME.
LONG TERM...SCA`S MAYBE NEEDED WEDNESDAY THROUGH THURSDAY.
&&
.GYX WATCHES/WARNINGS/ADVISORIES...
ME...NONE.
NH...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST TUESDAY FOR ANZ150-152-154.
&&
$$
UPDATE...HANES
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
658 AM EST MON MAR 5 2012
.SYNOPSIS...
A CLIPPER LOW PRESSURE SYSTEM WILL PUSH EAST ACROSS SOUTHERN
VIRGINIA THIS MORNING...MOVING OFFSHORE THROUGH THE AFTERNOON.
SPRAWLING HIGH PRESSURE WILL DOMINATE THE MID ATLANTIC WEATHER
TONIGHT INTO THURSDAY BEFORE A COLD FRONT APPROACHES AND SINKS SOUTH
ACROSS THE REGION THURSDAY NIGHT THROUGH FRIDAY. MORE HIGH PRESSURE
IS EXPECTED FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
GIVEN RADAR TRENDS...HAVE EXPANDED THE WINTER WEATHER ADVISORY TO
INCLUDE A FEW MORE COUNTIES. 06Z NAM/GFS AND RECENT RUC/HRRR RUNS
SUPPORT THIS ADJUSTMENT. IN FACT...AM WORRIED BY THE SNOWFALL
ACCUMULATIONS FROM THE HRRR AS THEY SUGGEST WARNING CRITERIA FOR
SNOW CLIPPING OUR SOUTHERN CWA. FEEL THAT THIS IS OVERDONE AND AM
HOLDING ONTO ADVISORIES FOR NOW...1 TO 3 INCHES ON THE NORTHERN
TIER OF THE ADVISORY AND 2 TO 4 INCHES ON THE SOUTHERN TIER.
BANDING WILL NEED TO BE WATCHED. MODELS CONTINUE TO SHOW A TIGHT
GRADIENT OF SNOWFALL AND HAVE NOT ADJUSTED THE NORTHERN FRINGE
ATTM. PREV BELOW...
POTENT SHORTWAVE/CLIPPER SYSTEM OVER THE EASTERN OHIO VALLEY WILL
MOVE TO THE EAST TODAY...PASSING OVER THE SOUTHERN APPALACHIANS THIS
MORNING AND THROUGH SOUTHERN VIRGINIA DURING THE MIDDAY AND EARLY
AFTERNOON HOURS.
00Z GUIDANCE SHIFTED THE TRACK OF THE LOW AND ASSOCIATED QPF A
LITTLE FURTHER TO THE NORTH. NCEP GUIDANCE CONTINUES TO SHOW THIS
STORM EXHIBITING A TIGHT GRADIENT OF SNOW. HAVE ALREADY EXPANDED THE
WINTER WEATHER ADVISORY TO INCLUDE SEVERAL MORE COUNTIES FROM
AUGUSTA EAST THROUGH ALBEMARLE/ORANGE/SPOTSYLVANIA. LATEST NCEP
GUIDANCE SUGGESTS THIS AREA WOULD BE ON THE NORTHERN FRINGE OF A
MODERATE TO HEAVY BAND OF SNOWFALL. IN ADDITION TO THE PVA
ASSOCIATED WITH THE SYSTEM...MODELS INDICATE THAT THIS AREA IS WHERE
THERE MAY ALSO BE ENHANCED FRONTOGENETIC FORCING. ALWAYS HAVE TO
WORRY ABOUT BANDING RESULTING IN MORE SNOWFALL. THIS WORRY IS
COMPOUNDED BY THE 06Z NAM JUST COMING IN...SUGGESTING WARNING
CALIBER AMOUNTS ACROSS NELSON AND SOUTHERN ALBEMARLE COUNTIES.
DON/T HAVE SUPPORT FROM OTHER GUIDANCE FOR A WARNING...SO WILL HOLD
WITH THE ADVISORY FOR NOW WITH THE HIGHEST TOTALS TOWARD NELSON
COUNTY. IN ADDITION...RECENT HRRR RUNS SUGGEST THAT ADVISORY
SNOWFALL COULD REACH A TIER OF COUNTIES FURTHER NORTH ALTHOUGH THIS
IS NOT PORTRAYED BY THE NAM/GFS WHICH SHOW THE TIGHT QPF GRADIENT
WELL. WILL HAVE TO KEEP AN EYE ON THIS POTENTIAL AS THE MORNING
PROGRESSES. HAVE THE NORTHERN FRINGE OF LOW POPS UP TO NEAR
INTERSTATE 66...WITH A DRY FORECAST UP TOWARD THE BALTIMORE AREA.
HAVE UNDERCUT MOS FOR TODAY ESPECIALLY ACROSS THE SOUTHERN PORTION
OF THE CWA GIVEN CLOUD COVER AND PRECIP.
CLIPPER WILL BE A FAST-MOVER...LIKELY OFF THE SOUTHEAST VIRGINIA
COAST BY MID AFTERNOON AND TAKING THE PRECIP WITH IT. SKIES WILL
REMAIN CLOUDY THROUGH THE AFTERNOON...BUT AS HIGH PRESSURE BUILDS IN
FROM THE WEST THIS EVENING SKIES WILL RAPIDLY CLEAR AND COLDER AIR
WILL MOVE INTO THE CWA.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
TUESDAY...RIDGE AXIS MOVES EAST ACROSS THE LWX CWA ON TUESDAY WITH
MAX TEMPS AROUND 50F ACROSS THE CWA...JUST BELOW NORMAL. THIS IS
EXCEPT FOR THE SHEN VLY AND WEST WHERE SWLY RETURN FLOW IN THE
AFTERNOON MIXES DOWN THE WARM AIR ADVECTING IN...EXPECT MID 50S OUT
THERE. FEW/SCT MID LEVEL CLOUDS ALONG A LOWER-MID LEVEL WARM
FRONT...BUT DRY.
WEDNESDAY INTO THURSDAY...HIGH PRESSURE CENTER ANCHORS TO THE SE OF
THE MID ATLANTIC COAST...PUMPING WARM GULF AIR ACROSS THE REGION.
EXPECT A WARMING TREND AND AMPLE SUNSHINE. 8C 850MB TEMPS ON
WED...WITH 10 TO 20 KT SWLY MIXING FLOW EXPECT AT LEAST MID 60S MAX
TEMPS WEDNESDAY. BETTER MIXING ON THURSDAY IN ADVANCE OF A COLD
FRONT. MAX TEMPS MID TO UPR 60S...70F SOUTH.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
COLD FRONT SAGS SOUTH THROUGH THE CENTRAL MID ATLANTIC THURSDAY
NIGHT THROUGH FRIDAY. INCREASED POPS TO HIGHER CHANCE RANGE...WITH
MOST OF THE AREA IN 40 POP THURSDAY NIGHT...WITH SRN MD 40 POP FOR
FRIDAY AS FRONT SAGS SOUTH THROUGH THE AREA.
HIGH PRESSURE OVER THE NRN MID ATLANTIC BEHIND THE COLD FRONT FOR
THE WEEKEND...EXPECT AN ONSHORE FLOW AND TEMPERATURES BACK TO AROUND
NORMAL. WILL HAVE TO WATCH OUT FOR THE FRONT TO STALL AND A CAD
SCENARIO TO SETUP FOR THE WEEKEND.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
SN WILL DEVELOP AT CHO BTWN 11-12Z...BEGINNING A PERIOD OF IFR/LIFR
CONDITIONS LIKELY LASTING UNTIL AROUND NOON. HAVE KEPT PRECIP SOUTH
OF ALL OTHER TERMINALS...BUT THERE IS AN OUTSIDE CHANCE THAT LIGHT
SN MAKES IT TO IAD-DCA ON THE NORTHERN FRINGE OF PRECIP ASSOCIATED
WITH A CLIPPER THAT PASSES SOUTH OF THE REGION TODAY. AS CLIPPER
MOVES OFF THE COAST...WINDS WILL BECOME GUSTY THIS AFTERNOON BEFORE
DIMINISHING TONIGHT AS HIGH PRESSURE BUILDS IN.
HIGH PRESSURE/VFR TUESDAY INTO THURSDAY. NLY FLOW TUESDAY MORNING
BECOMES LIGHT AND VARIABLE UNDER THE HIGH PRESSURE CENTER...THEN
BECOMES SWLY THROUGH THE AFTERNOON AS THE CENTER MOVES OFFSHORE.
SLY/SWLY FLOW THEN THROUGH THURSDAY AS HIGH PRESSURE ANCHORS EAST OF
CAPE HATTERAS AND AS A COLD FRONT APPROACHES. COLD FRONTAL PASSAGE
WITH RAIN SHOWERS THURSDAY NIGHT/FRIDAY.
&&
.MARINE...
CLIPPER PASSES SOUTH OF THE WATERS TODAY. GRADIENT TIGHTENS UP THIS
AFTERNOON FOR SCA CONDITIONS TO DEVELOP. SCA WINDS MAY LAST WELL
INTO THE EVENING BEFORE HIGH PRESSURE BUILDS IN OVERNIGHT.
NLY/NWLY FLOW CONTINUES TO GUST AROUND 18KT THROUGH MID TUESDAY
MORNING FOR SRN MD PORTION OF CHES BAY...SO SCA WAS EXTENDED UNTIL
15Z FOR SOUTH OF DRUM PT. LIGHT AND VARIABLE FLOW THEN BECOMES
SLY/SWLY TUESDAY AFTERNOON AND CONTINUES THROUGH THURSDAY AS HIGH
PRESSURE ANCHORS EAST OF CAPE HATTERAS. SCA POSSIBLE WEDNESDAY NIGHT
INTO FRIDAY. COLD FRONT SAGS SOUTH THROUGH THE CHESAPEAKE BAY
REGION LATE THURSDAY NIGHT THROUGH FRIDAY BRINGING SCATTERED RAIN
SHOWERS.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR VAZ025-026-
036>038-050-056-503-504.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 3 PM THIS AFTERNOON TO 6 AM EST
TUESDAY FOR ANZ531-532-538>542.
SMALL CRAFT ADVISORY FROM 3 PM THIS AFTERNOON TO 10 AM EST
TUESDAY FOR ANZ533-534-537-543.
SMALL CRAFT ADVISORY FROM 3 PM THIS AFTERNOON TO MIDNIGHT EST
TONIGHT FOR ANZ530-535-536.
&&
$$
SYNOPSIS...BPP
NEAR TERM...BPP
SHORT TERM...BAJ
LONG TERM...BAJ
AVIATION...BPP/BAJ
MARINE...BPP/BAJ
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
400 AM EST MON MAR 5 2012
.SYNOPSIS...
A CLIPPER LOW PRESSURE SYSTEM WILL PUSH EAST ACROSS SOUTHERN
VIRGINIA THIS MORNING...MOVING OFFSHORE THROUGH THE AFTERNOON.
SPRAWLING HIGH PRESSURE WILL DOMINATE THE MID ATLANTIC WEATHER
TONIGHT INTO THURSDAY BEFORE A COLD FRONT APPROACHES AND SINKS SOUTH
ACROSS THE REGION THURSDAY NIGHT THROUGH FRIDAY. MORE HIGH PRESSURE
IS EXPECTED FOR THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
POTENT SHORTWAVE/CLIPPER SYSTEM OVER THE EASTERN OHIO VALLEY WILL
MOVE TO THE EAST TODAY...PASSING OVER THE SOUTHERN APPALACHIANS THIS
MORNING AND THROUGH SOUTHERN VIRGINIA DURING THE MIDDAY AND EARLY
AFTERNOON HOURS.
00Z GUIDANCE SHIFTED THE TRACK OF THE LOW AND ASSOCIATED QPF A
LITTLE FURTHER TO THE NORTH. NCEP GUIDANCE CONTINUES TO SHOW THIS
STORM EXHIBITING A TIGHT GRADIENT OF SNOW. HAVE ALREADY EXPANDED THE
WINTER WEATHER ADVISORY TO INCLUDE SEVERAL MORE COUNTIES FROM
AUGUSTA EAST THROUGH ALBEMARLE/ORANGE/SPOTSYLVANIA. LATEST NCEP
GUIDANCE SUGGESTS THIS AREA WOULD BE ON THE NORTHERN FRINGE OF A
MODERATE TO HEAVY BAND OF SNOWFALL. IN ADDITION TO THE PVA
ASSOCIATED WITH THE SYSTEM...MODELS INDICATE THAT THIS AREA IS WHERE
THERE MAY ALSO BE ENHANCED FRONTOGENETIC FORCING. ALWAYS HAVE TO
WORRY ABOUT BANDING RESULTING IN MORE SNOWFALL. THIS WORRY IS
COMPOUNDED BY THE 06Z NAM JUST COMING IN...SUGGESTING WARNING
CALIBER AMOUNTS ACROSS NELSON AND SOUTHERN ALBEMARLE COUNTIES.
DON/T HAVE SUPPORT FROM OTHER GUIDANCE FOR A WARNING...SO WILL HOLD
WITH THE ADVISORY FOR NOW WITH THE HIGHEST TOTALS TOWARD NELSON
COUNTY. IN ADDITION...RECENT HRRR RUNS SUGGEST THAT ADVISORY
SNOWFALL COULD REACH A TIER OF COUNTIES FURTHER NORTH ALTHOUGH THIS
IS NOT PORTRAYED BY THE NAM/GFS WHICH SHOW THE TIGHT QPF GRADIENT
WELL. WILL HAVE TO KEEP AN EYE ON THIS POTENTIAL AS THE MORNING
PROGRESSES. HAVE THE NORTHERN FRINGE OF LOW POPS UP TO NEAR
INTERSTATE 66...WITH A DRY FORECAST UP TOWARD THE BALTIMORE AREA.
HAVE UNDERCUT MOS FOR TODAY ESPECIALLY ACROSS THE SOUTHERN PORTION
OF THE CWA GIVEN CLOUD COVER AND PRECIP.
CLIPPER WILL BE A FAST-MOVER...LIKELY OFF THE SOUTHEAST VIRGINIA
COAST BY MID AFTERNOON AND TAKING THE PRECIP WITH IT. SKIES WILL
REMAIN CLOUDY THROUGH THE AFTERNOON...BUT AS HIGH PRESSURE BUILDS IN
FROM THE WEST THIS EVENING SKIES WILL RAPIDLY CLEAR AND COLDER AIR
WILL MOVE INTO THE CWA.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
TUESDAY...RIDGE AXIS MOVES EAST ACROSS THE LWX CWA ON TUESDAY WITH
MAX TEMPS AROUND 50F ACROSS THE CWA...JUST BELOW NORMAL. THIS IS
EXCEPT FOR THE SHEN VLY AND WEST WHERE SWLY RETURN FLOW IN THE
AFTERNOON MIXES DOWN THE WARM AIR ADVECTING IN...EXPECT MID 50S OUT
THERE. FEW/SCT MID LEVEL CLOUDS ALONG A LOWER-MID LEVEL WARM
FRONT...BUT DRY.
WEDNESDAY INTO THURSDAY...HIGH PRESSURE CENTER ANCHORS TO THE SE OF
THE MID ATLANTIC COAST...PUMPING WARM GULF AIR ACROSS THE REGION.
EXPECT A WARMING TREND AND AMPLE SUNSHINE. 8C 850MB TEMPS ON
WED...WITH 10 TO 20 KT SWLY MIXING FLOW EXPECT AT LEAST MID 60S MAX
TEMPS WEDNESDAY. BETTER MIXING ON THURSDAY IN ADVANCE OF A COLD
FRONT. MAX TEMPS MID TO UPR 60S...70F SOUTH.
&&
.LONG TERM /FRIDAY THROUGH SUNDAY/...
COLD FRONT SAGS SOUTH THROUGH THE CENTRAL MID ATLANTIC THURSDAY
NIGHT THROUGH FRIDAY. INCREASED POPS TO HIGHER CHANCE RANGE...WITH
MOST OF THE AREA IN 40 POP THURSDAY NIGHT...WITH SRN MD 40 POP FOR
FRIDAY AS FRONT SAGS SOUTH THROUGH THE AREA.
HIGH PRESSURE OVER THE NRN MID ATLANTIC BEHIND THE COLD FRONT FOR
THE WEEKEND...EXPECT AN ONSHORE FLOW AND TEMPERATURES BACK TO AROUND
NORMAL. WILL HAVE TO WATCH OUT FOR THE FRONT TO STALL AND A CAD
SCENARIO TO SETUP FOR THE WEEKEND.
&&
.AVIATION /09Z MONDAY THROUGH FRIDAY/...
SN WILL DEVELOP AT CHO BTWN 11-12Z...BEGINNING A PERIOD OF IFR/LIFR
CONDITIONS LIKELY LASTING UNTIL AROUND NOON. HAVE KEPT PRECIP SOUTH
OF ALL OTHER TERMINALS...BUT THERE IS AN OUTSIDE CHANCE THAT LIGHT
SN MAKES IT TO IAD-DCA ON THE NORTHERN FRINGE OF PRECIP ASSOCIATED
WITH A CLIPPER THAT PASSES SOUTH OF THE REGION TODAY. AS CLIPPER
MOVES OFF THE COAST...WINDS WILL BECOME GUSTY THIS AFTERNOON BEFORE
DIMINISHING TONIGHT AS HIGH PRESSURE BUILDS IN.
HIGH PRESSURE/VFR TUESDAY INTO THURSDAY. NLY FLOW TUESDAY MORNING
BECOMES LIGHT AND VARIABLE UNDER THE HIGH PRESSURE CENTER...THEN
BECOMES SWLY THROUGH THE AFTERNOON AS THE CENTER MOVES OFFSHORE.
SLY/SWLY FLOW THEN THROUGH THURSDAY AS HIGH PRESSURE ANCHORS EAST OF
CAPE HATTERAS AND AS A COLD FRONT APPROACHES. COLD FRONTAL PASSAGE
WITH RAIN SHOWERS THURSDAY NIGHT/FRIDAY.
&&
.MARINE...
CLIPPER PASSES SOUTH OF THE WATERS TODAY. GRADIENT TIGHTENS UP THIS
AFTERNOON FOR SCA CONDITIONS TO DEVELOP. SCA WINDS MAY LAST WELL
INTO THE EVENING BEFORE HIGH PRESSURE BUILDS IN OVERNIGHT.
NLY/NWLY FLOW CONTINUES TO GUST AROUND 18KT THROUGH MID TUESDAY
MORNING FOR SRN MD PORTION OF CHES BAY...SO SCA WAS EXTENDED UNTIL
15Z FOR SOUTH OF DRUM PT. LIGHT AND VARIABLE FLOW THEN BECOMES
SLY/SWLY TUESDAY AFTERNOON AND CONTINUES THROUGH THURSDAY AS HIGH
PRESSURE ANCHORS EAST OF CAPE HATTERAS. SCA POSSIBLE WEDNESDAY NIGHT
INTO FRIDAY. COLD FRONT SAGS SOUTH THROUGH THE CHESAPEAKE BAY
REGION LATE THURSDAY NIGHT THROUGH FRIDAY BRINGING SCATTERED RAIN
SHOWERS.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR VAZ025-036-
037-050-056.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 3 PM THIS AFTERNOON TO 6 AM EST
TUESDAY FOR ANZ531-532-538>542.
SMALL CRAFT ADVISORY FROM 3 PM THIS AFTERNOON TO 10 AM EST
TUESDAY FOR ANZ533-534-537-543.
SMALL CRAFT ADVISORY FROM 3 PM THIS AFTERNOON TO MIDNIGHT EST
TONIGHT FOR ANZ530-535-536.
&&
$$
SYNOPSIS...BPP
NEAR TERM...BPP
SHORT TERM...BAJ
LONG TERM...BAJ
AVIATION...BAJ/BPP
MARINE...BAJ/BPP
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
811 PM EST TUE MAR 6 2012
.UPDATE...
ISSUED AT 810 PM EST TUE MAR 6 2012
UPDATED TO LOWER MIN TEMPS A BIT OVER THE CENTRAL AND E GIVEN RECENT
TRENDS WITH FAIRLY LGT WINDS/MOCLR SKIES. EXPECT TEMPS TO STEADY OUT
AND THEN RISE A BIT IN THESE AREAS WITH ARRIVAL OF THICKER CLDS/MORE
LLVL MSTR LATER WITH STEADY SSW WIND. ADDED PATCHY FOG EARLIER OVER
THE E GIVEN SHARPER DIURNAL TEMP FALL THERE THIS EVNG.
&&
.SYNOPSIS...
ISSUED AT 405 PM EST TUE MAR 6 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A TROF MOVING INTO THE
ROCKIES WITH A BROAD DOWNSTREAM RIDGE EXPANDING FROM THE CNTRL TO
ERN CONUS. MAIN PORTION OF THIS TROF WILL SHIFT ACROSS THE NRN
CONUS/GREAT LAKES AND NEW ENGLAND OVER THE NEXT SEVERAL DAYS WHILE
ENERGY IN THE SRN PORTION OF THE TROF BREAKS OUT AND CLOSES OFF OVER
THE SW STATES. TROF WILL BRING A PERIOD OF PCPN WED THRU THU.
EVENTUALLY...THE SW LOW WILL EJECT OUT TO THE NE OVER THE
WEEKEND/EARLY NEXT WEEK. WHAT AFFECTS THE LOW WILL HAVE OVER THE
UPPER LAKES REMAINS TO BE SEEN.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 405 PM EST TUE MAR 6 2012
IN THE SHORT TERM...CONCERNS REVOLVE AROUND TEMP TRENDS...FOG
DEVELOPMENT AND THEN PCPN WED ASSOCIATED WITH COLD FRONT/TROF MOVING
INTO THE UPPER LAKES.
DWPTS ARE RISING INTO THE MID 30S TO LWR 40S AS FAR NE SE MN/SW WI
THIS AFTN WITH TRAJECTORIES BRINGING THAT MOISTURE INTO UPPER MI
DURING THE NIGHT AND WED MORNING. WITH THE LOW-LEVEL MOISTURE
ADVECTION OVER THE SNOW COVER...STRATUS/FOG SHOULD EVENTUALLY
DEVELOP TONIGHT. DENSE FOG MAY DEVELOP...ESPECIALLY OVER UPSLOPE
HIGHER TERRAIN LATE TONIGHT INTO WED. IF THERE WAS SOME ADDITIONAL
MOISTURE FROM RAIN/DRIZZLE...WOULD GO WITH MORE OF A DENSE FOG
WORDING. FOR NOW...GOING FCST OF AN INCREASE IN LOWER CLOUDS AND FOG
DEVELOPMENT...MAINLY LATER TONIGHT...LOOKS ON TRACK. TEMPS SHOULDN`T
FALL MUCH IF AT ALL UNDER MOISTURE ADVECTION AND FAIRLY TIGHT PRES
GRADIENT/STIRRING WINDS. MINS SHOULD BE IN THE MID 30S TO LWR 40S...
WARMEST IN THE DOWNSLOPE AREAS NEAR LAKE SUPERIOR.
COLD FRONT IS STILL ON TRACK TO MOVE THRU THE AREA LATER WED
AFTN/EVENING AS SFC LOW MOVES ACROSS NORTHERN PORTIONS OF ONTARIO.
EVEN WITH CLOUDS/FOG (POSSIBLY DENSE) AHEAD OF THE FRONT...WARM
START TO THE DAY SHOULD ALLOW TEMPS TO RISE WELL INTO THE 40S AHEAD
OF THE FRONT WED. FCST SOUNDINGS FROM NAM/GFS INDICATE RAIN WILL BE
PTYPE. EXCEPTION WILL BE THE FAR W LATE IN THE DAY. SOUNDINGS THERE
INITIALLY SHOW COOLING WORKING IN BLO 850MB...THEN SHOW ALL OF THE
PROFILE NEAR OR BLO 0C LATE AFTN...RESULTING IN CHANGE TO SNOW...
WITH SLEET POSSIBLE AT LEAST BRIEFLY AS WELL. WITH SLOWER COOLING
NOTED BY GEM/UKMET...OPTED TO SLOW CHANGEOVER BY A FEW HRS. NOT
EXPECTING ANY SNOW/SLEET ACCUMULATION WED WITH TEMPS WELL INTO THE
30S THRU LATE AFTN OVER THE W. OTHERWISE...WITH ASSISTANCE OF RIGHT
ENTRANCE OF UPPER JET...EXPECT AN AREA OF -RA TO DEVELOP
(LIKELY/CATEGORICAL POPS)...MOSTLY ALONG/JUST BEHIND COLD FRONT.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 405 PM EST TUE MAR 6 2012
COLD FRONT WILL BE STRETCHED FROM NE TO SW ACROSS THE CNTRL/ERN CWA
AT THE START OF THE PERIOD...WHILE THE UPPER TROUGH IS STARTING TO
PUSH INTO THE UPPER GREAT LKS. THIS FRONT WILL CONTINUE TO SLIDE SE
INTO NRN LOWER MI DURING THE EARLY OVERNIGHT HRS. PCPN DEVELOPING
ALONG THE FRONT TOMORROW AFTN WILL LARGELY BE FOCUSED OVER THE ERN
CWA AT THE START OF THE PERIOD. THIS SHOULD BE FALLING AS RAIN...DUE
TO THE ABUNDANT WAA FROM H925-800 LEADING TO TEMPS AT OR ABOVE 3C.
FARTHER W IN CNTRL AND WRN UPPER MI...LLVL COLD AIR SURGING IN
BEHIND THE FRONT WILL BRING IN A COLD LAYER FOR THE PCPN TO FALL
INTO. THE MAIN QUESTION IS HOW QUICKLY THAT COLD AIR WILL SURGE IN
BEHIND THE PCPN SHIFTING TO THE SE. MAY NOT BE ENOUGH COLD AIR TO
ALLOW SLEET TO OCCUR...BUT DID MENTION A SLIGHT CHANCE OF IT ON THE
BACK SIDE OF THE MAIN PCPN. IN ADDITION...SOME CONCERNS ON ICE
CRYSTAL PRESENCE IN THE CLOUDS ON THE BACK EDGE OF THE PCPN. EVEN AS
TEMPS START TO COOL BEHIND THE FRONT...THEY REALLY DON/T FALL MUCH
BELOW -5C UNTIL THE BULK OF THE PCPN HAS MOVED TO THE EAST. THINKING
IT WILL LARGELY BE A RAIN...THEN A QUICK PERIOD OF SLEET AND EITHER
END OR BE A SLIGHT DZ/FLURRIES.
THINK BEST CHANCES FOR SNOW WILL BE OVER THE W IN THE EVENING...AS
THE COLD AIR ALLOWS FOR LK ENHANCEMENT WITH H900-875 TEMPS FALLING
TO -8C. CLOUD DEPTH SHOULD BE LIMITED WITH THE INVERSION AROUND H850
OR 3KFT. THUS...WILL MAINLY BE FLURRIES OR LIGHT SNOW SHOWERS AND
LINGERED CHANCES/SLIGHTS OVER THE NW FAVORED LOCATIONS IN THE W
THROUGH THE EARLY OVERNIGHT HRS. DRY LLVL AIR WILL THEN QUICKLY WORK
IN OVERNIGHT...SO HAVE DIMINISHED THE LINGERING POPS QUICKLY FROM W
TO E NEAR LK SUPERIOR.
THERE IS SOME POTENTIAL FOR CLEARING OVER THE INTERIOR W LATE IN THE
NIGHT...WHICH COULD ALLOW TEMPS TO FALL BELOW GUIDANCE WITH PWAT
VALUES AROUND 55 PERCENT OF NORMAL. WINDS WILL BE DIMINISHING WITH
THE APPROACHING SFC RIDGE...BUT MAY NOT ARRIVE EARLY ENOUGH TO
MAXIMIZE THE RADIATIONAL COOLING. WILL HIGHLIGHT THE COLDEST VALUES
NEAR WATERSMEET WITH LOWS IN THE UPPER TEENS.
UPPER TROUGH WILL BE MOVING OVER THE UPPER GREAT LAKES THROUGH
THE DAY ON THURS...ALLOWING SFC LOW TO DEVELOP OVER SRN ONTARIO
THURS AFTN AND INTENSIFY AS IT MOVES SE ON THURS NIGHT. DRY AIR
ABOVE H850 BEHIND THE FRONT WILL BE PUSHING FROM NW TO SE ACROSS THE
AREA THURS MORN AHEAD OF SECONDARY TROUGH BRINGING DEEPER MOISTURE
AND COLDER AIR. THINK THIS WILL LEAD TO A PERIOD OF PARTLY CLOUDY
TO MOSTLY SUNNY SKY OVER MUCH OF THE CWA IN THE MORNING. THEN...AS
THE TROUGH MOVES INTO THE AREA AND BRINGS DEEPER MOISTURE AND
H850-700 Q-VECTOR CONV...HAVE INCREASED CLOUDS AND BRING
SLIGHT/CHANCES OF SNOW BACK IN THE AFTN NEAR LK SUPERIOR.
UPPER TROUGH WILL START TO PUSH E ON THURS NIGHT AND CONTINUE E ON
FRI...AS RIDGING STARTS TO MOVE OVER THE AREA AND SFC HIGH PUSHES
INTO THE WRN GREAT LKS. WITH SECONDARY COLD FRONT DROPPING SE
ACROSS LK SUPERIOR...EXPECT ADDITIONAL LLVL MOISTURE AND FALLING
H850 TEMPS TOWARDS -13C TO LEAD TO INCREASING LAKE
EFFECT/ENHANCEMENT FOR AREAS NEAR LK SUPERIOR. WITH THE STRONG NW
AND THEN NNW WINDS...EXPECT CLOUD COVER TO SPREAD ACROSS MUCH OF
THE AREA THURS NIGHT AND CONTINUE INTO FRI MORNING. WITH THE COLD
AIR SPILLING IN...EXPECT GUSTY WINDS AS H925 WINDS TO 35KTS OVER THE
NE HALF OF THE CWA TO MIX TO THE SFC AND PRODUCE 25-35KT GUSTS NEAR
LK SUPERIOR E OF MARQUETTE. OVERALL...DON/T EXPECT TOO MUCH SNOW
ACCUM AS THE PERIOD OF FAVORABLE CONDITIONS IT FAIRLY LIMITED ON
THURS NIGHT...BEFORE DRIER AIR ARRIVES AND LOWERING INVERSION
HEADING THROUGH THE DAY ON FRI. IN ADDITION...WITH THE INCREASING
H850 WAA ON FRI AFTN OVER THE WRN LK WILL ALSO AID TO END THE
LINGERING LES FROM W TO E THROUGH THE DAY FRI. ALL IN
ALL...THURS AND FRI LOOK TO BE A PERIOD OF NORMAL TO BELOW
NORMAL TEMPS ACROSS THE AREA AHEAD OF THE POTENTIAL WARM-UP FOR
THE WEEKEND INTO NEXT WEEK.
DAYS 4 THROUGH 7 /FRI NIGHT THROUGH TUESDAY/...
UPPER LOW SPINNING OVER THE FOUR CORNERS REGION ON FRI NIGHT WILL
BEGIN TO GET CAUGHT UP WITH THE FLOW AND DRIFT NNE.
MEANWHILE...NEARLY ZONAL FLOW NRN STREAM LOOKS TO BE SETUP OVER SRN
CANADA...KEEPING THE COLD AIR WELL N OF THE UPPER GREAT LKS.
12Z RUNS CONTINUE THE DIFFERENCES WITH THE TRACK OF THE
UPPER LOW. HPC PREFERS A CONSENSUS SOLN NOT INCLUDING THE
GFS...WHICH TRACKS THE LOW MUCH FASTER AND FARTHER SE. 12Z RUN IS
THE SAME AND REMAINS VERY CONSISTENT OVER THE LAST SEVERAL
RUNS...WHICH COULD LEAD SOME CREDIT TO THE THAT SOLN. ENS MEAN ON
ECMWF/GEM IS A LITTLE SLOWER THAN THE DETERMINISTIC RUN...BUT
FOLLOWS A SIMILAR TRACK. OVERALL CONSENSUS PULLS THE UPPER LOW
THROUGH THE GREAT LKS REGION SUN INTO MON. WILL CONTINUE TO MENTION
CHANCE POPS ACROSS THE AREA...WHICH SHOULD FALL AS RAIN DUE TO THE
WARM AIR ALREADY IN PLACE.
EXTENDED MODELS CONTINUE TO SHOW THE POTENTIAL FOR A BIG WARM UP
BEHIND THE UPPER LOW THAT MOVES THROUGH THE GREAT LKS. AMPLIFYING
AND NEARLY STATIONARY TROUGH OFF THE W COAST OF THE CONUS WILL LEAD
TO AMPLIFYING RIDGE OVER THE CANADIAN PRAIRIES. THIS WILL ALLOW SFC
HIGH TO BE STATIONED OVER THE ERN CONUS AND WITH THE MAIN LOWS
TRACKING WELL TO THE N THROUGH CANADA...EXPECT SRLY FLOW TO BE SETUP
OVER THE CWA. CONSENSUS OF THE MODELS GIVES VALUES IN THE 40S AND
NEAR 50 ALONG THE WI BORDER FOR HIGHS ON TUES. THIS IS USUALLY UNDER
DONE IN WELL ABOVE NORMAL SITUATIONS AND THE ECMWF /WHICH ALMOST
ALWAYS VERIFIES THE BEST IN THESE ABOVE NORMAL SITUATIONS/ HAS
VALUES ABOUT 7-10 DEGREES WARMER THAN THE CONSENSUS. THE TEMPS LOOK
TO GET EVEN WARMER HEADING INTO WED/THURS. ECMWF HAS TEMPS FOR
WED/THURS OF NEXT WEEK OVER THE W HALF IN THE 60S WITH COOLER TEMPS
NEAR LK MI WITH THE SSW FLOW. ECMWF EVEN ATTEMPTS TO TRY AN PUSH A
FEW 70S ALONG THE WI BORDER.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 626 PM EST TUE MAR 6 2012
VFR CONDITIONS WILL PREVAIL AT ALL 3 SITES THRU AT LEAST EARLY
EVENING. INCREASING LOW-LEVEL MOISTURE OVER SNOWPACK SHOULD RESULT
IN LOW CLOUDS/FOG DEVELOPING TONIGHT...WITH BEST CHC OF LOW
MVFR/POSSIBLE IFR CIG AT KSAW DUE TO UPSLOPE COMPONENT TO S WIND.
DOWNSLOPE NATURE OF S WIND AT KIWD/KCMX SHOULD HELP TO MAINTAIN VFR
CONDITIONS AT THOSE SITES. WITH FAIRLY STRONG WINDS ABOVE LOW-LEVEL
INVERSION...EXPECT LLWS TONIGHT. IFR CONDITIONS ARE LIKELY TO
DEVELOP AT ALL SITES WED MORNING AS LOW-LEVEL MOISTURE CONTINUES TO
INCREASE AHEAD OF APPROACHING COLD FRONT. A DISTURBANCE MOVING NEWD
ALONG THIS FRONT WILL BRING A BETTER CHANCE OF -RA AND LIFR
CONDITIONS COINCIDENT WITH AND FOLLOWING THE FROPA AS THE -RA
CHANGES TO -SN AT LEAST AT THE WESTERN SITES WITH THE RETURN OF
COLDER AIR.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 405 PM EST TUE MAR 6 2012
SOUTHERLY WINDS OF 20-30KT OVER ERN LAKE SUPERIOR (LIGHTER OVER THE
W) AHEAD OF AN APPROACHING COLD FRONT WILL SLOWLY DIMINISH TONIGHT.
WINDS SHOULD MOSTLY DROP OFF BLO 20KT FOR MUCH OF WED AS THE COLD
FRONT ARRIVES. WITH THE PASSAGE OF COLD FRONT...NW WINDS WILL BE ON
THE INCREASE WED EVENING AND THEN THRU THU AS A FOLLOWING LOW PRES
CENTER PASSES SE ACROSS NRN ONTARIO. UNDER CAA/INCREASING OVERWATER
INSTABILITY...NW WINDS WILL INCREASE TO 20-30KT...ESPECIALLY THU/THU
NIGHT. GALES ARE A POSSIBILITY. WINDS WILL DIMINISH TO UNDER 20KT BY
LATE FRIDAY AFTN AS HIGH PRESSURE BUILDS INTO THE REGION. ON THE
BACKSIDE OF THE HIGH...SW WINDS WILL RAMP BACK UP TO 20-30KT SAT.
&&
.HYDROLOGY...
ISSUED AT 405 PM EST TUE MAR 6 2012
EVEN WITH THE WARM TEMPS OVER THE NEXT 24-36 HOURS...DON/T EXPECT
MUCH IF ANY MELTING TO OCCUR DUE TO THE UN-RIPE CONDITIONS OF THE
SNOW PACK. LOOKING AT NOHRSC CURRENT AND FUTURE SNOWPACK
TEMPERATURES...ONLY THE TOP AND MIDDLE LAYERS /TOP 2-10 INCHES
DEPENDING ON LOCATION/ OF THE SNOWPACK BECOME RIPE OVER THE SW HALF
OF THE CWA BY WED EVENING. THIS WILL LIKELY LEAD TO SOME
COMPACTION/MELTING OF THE TOP OF THE EXISTING SNOWPACK...BUT IT
SHOULD STILL RETAIN THE WATER AND KEEP MUCH OR ALL OF THE MOISTURE
IN THE SNOWPACK THROUGH WED EVENING.
WITH COOLER TEMPERATURES EXPECTED BEHIND THE COLD FRONT ON
WED...DON/T EXPECT ANY MELTING TO OCCUR WED NIGHT INTO SAT. WITH THE
WARMING TREND EXPECTED DURING THE WEEKEND AND INTO NEXT WEEK...WILL
NEED TO KEEP AN EYE ON A SLOWLY RIPENING SNOWPACK. THE POTENTIAL FOR
RAIN ON SUN/MON MAY ASSIST IN THIS RIPENING THROUGH THE FIRST PART
OF NEXT WEEK.
THE POTENTIAL FOR MELTING OF THE SNOWPACK COULD GREATLY INCREASE
HEADING INTO THE MIDDLE OF NEXT WEEK...AS OVERNIGHT LOWS AND TD
VALUES RISE ABOVE FREEZING. THE EXTENDED MODELS HAVE BEEN SHOWING
WELL ABOVE NORMAL TEMPERATURES /10 PLUS DEGREES/ FOR THE MIDDLE OF
NEXT WEEK. IF THE WARM TEMPS SHOWN ON THE ECMWF /HIGHS IN THE 60S
FOR WED AND THURS/ COME TO FRUITION...THE MELT MAY BE FAIRLY FAST
AND RUN OFF DIRECTLY INTO AREA RIVERS. THUS...WILL NEED TO KEEP AN
EYE ON AREA RIVERS AND STREAMS NEXT WEEK FOR THE POTENTIAL OF RISING
LEVELS DUE TO SNOWMELT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...KC
SYNOPSIS...ROLFSON
SHORT TERM...ROLFSON
LONG TERM...SRF
AVIATION...KC
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
630 PM EST TUE MAR 6 2012
.SYNOPSIS...
ISSUED AT 405 PM EST TUE MAR 6 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A TROF MOVING INTO THE
ROCKIES WITH A BROAD DOWNSTREAM RIDGE EXPANDING FROM THE CNTRL TO
ERN CONUS. MAIN PORTION OF THIS TROF WILL SHIFT ACROSS THE NRN
CONUS/GREAT LAKES AND NEW ENGLAND OVER THE NEXT SEVERAL DAYS WHILE
ENERGY IN THE SRN PORTION OF THE TROF BREAKS OUT AND CLOSES OFF OVER
THE SW STATES. TROF WILL BRING A PERIOD OF PCPN WED THRU THU.
EVENTUALLY...THE SW LOW WILL EJECT OUT TO THE NE OVER THE
WEEKEND/EARLY NEXT WEEK. WHAT AFFECTS THE LOW WILL HAVE OVER THE
UPPER LAKES REMAINS TO BE SEEN.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 405 PM EST TUE MAR 6 2012
IN THE SHORT TERM...CONCERNS REVOLVE AROUND TEMP TRENDS...FOG
DEVELOPMENT AND THEN PCPN WED ASSOCIATED WITH COLD FRONT/TROF MOVING
INTO THE UPPER LAKES.
DWPTS ARE RISING INTO THE MID 30S TO LWR 40S AS FAR NE SE MN/SW WI
THIS AFTN WITH TRAJECTORIES BRINGING THAT MOISTURE INTO UPPER MI
DURING THE NIGHT AND WED MORNING. WITH THE LOW-LEVEL MOISTURE
ADVECTION OVER THE SNOW COVER...STRATUS/FOG SHOULD EVENTUALLY
DEVELOP TONIGHT. DENSE FOG MAY DEVELOP...ESPECIALLY OVER UPSLOPE
HIGHER TERRAIN LATE TONIGHT INTO WED. IF THERE WAS SOME ADDITIONAL
MOISTURE FROM RAIN/DRIZZLE...WOULD GO WITH MORE OF A DENSE FOG
WORDING. FOR NOW...GOING FCST OF AN INCREASE IN LOWER CLOUDS AND FOG
DEVELOPMENT...MAINLY LATER TONIGHT...LOOKS ON TRACK. TEMPS SHOULDN`T
FALL MUCH IF AT ALL UNDER MOISTURE ADVECTION AND FAIRLY TIGHT PRES
GRADIENT/STIRRING WINDS. MINS SHOULD BE IN THE MID 30S TO LWR 40S...
WARMEST IN THE DOWNSLOPE AREAS NEAR LAKE SUPERIOR.
COLD FRONT IS STILL ON TRACK TO MOVE THRU THE AREA LATER WED
AFTN/EVENING AS SFC LOW MOVES ACROSS NORTHERN PORTIONS OF ONTARIO.
EVEN WITH CLOUDS/FOG (POSSIBLY DENSE) AHEAD OF THE FRONT...WARM
START TO THE DAY SHOULD ALLOW TEMPS TO RISE WELL INTO THE 40S AHEAD
OF THE FRONT WED. FCST SOUNDINGS FROM NAM/GFS INDICATE RAIN WILL BE
PTYPE. EXCEPTION WILL BE THE FAR W LATE IN THE DAY. SOUNDINGS THERE
INITIALLY SHOW COOLING WORKING IN BLO 850MB...THEN SHOW ALL OF THE
PROFILE NEAR OR BLO 0C LATE AFTN...RESULTING IN CHANGE TO SNOW...
WITH SLEET POSSIBLE AT LEAST BRIEFLY AS WELL. WITH SLOWER COOLING
NOTED BY GEM/UKMET...OPTED TO SLOW CHANGEOVER BY A FEW HRS. NOT
EXPECTING ANY SNOW/SLEET ACCUMULATION WED WITH TEMPS WELL INTO THE
30S THRU LATE AFTN OVER THE W. OTHERWISE...WITH ASSISTANCE OF RIGHT
ENTRANCE OF UPPER JET...EXPECT AN AREA OF -RA TO DEVELOP
(LIKELY/CATEGORICAL POPS)...MOSTLY ALONG/JUST BEHIND COLD FRONT.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 405 PM EST TUE MAR 6 2012
COLD FRONT WILL BE STRETCHED FROM NE TO SW ACROSS THE CNTRL/ERN CWA
AT THE START OF THE PERIOD...WHILE THE UPPER TROUGH IS STARTING TO
PUSH INTO THE UPPER GREAT LKS. THIS FRONT WILL CONTINUE TO SLIDE SE
INTO NRN LOWER MI DURING THE EARLY OVERNIGHT HRS. PCPN DEVELOPING
ALONG THE FRONT TOMORROW AFTN WILL LARGELY BE FOCUSED OVER THE ERN
CWA AT THE START OF THE PERIOD. THIS SHOULD BE FALLING AS RAIN...DUE
TO THE ABUNDANT WAA FROM H925-800 LEADING TO TEMPS AT OR ABOVE 3C.
FARTHER W IN CNTRL AND WRN UPPER MI...LLVL COLD AIR SURGING IN
BEHIND THE FRONT WILL BRING IN A COLD LAYER FOR THE PCPN TO FALL
INTO. THE MAIN QUESTION IS HOW QUICKLY THAT COLD AIR WILL SURGE IN
BEHIND THE PCPN SHIFTING TO THE SE. MAY NOT BE ENOUGH COLD AIR TO
ALLOW SLEET TO OCCUR...BUT DID MENTION A SLIGHT CHANCE OF IT ON THE
BACK SIDE OF THE MAIN PCPN. IN ADDITION...SOME CONCERNS ON ICE
CRYSTAL PRESENCE IN THE CLOUDS ON THE BACK EDGE OF THE PCPN. EVEN AS
TEMPS START TO COOL BEHIND THE FRONT...THEY REALLY DON/T FALL MUCH
BELOW -5C UNTIL THE BULK OF THE PCPN HAS MOVED TO THE EAST. THINKING
IT WILL LARGELY BE A RAIN...THEN A QUICK PERIOD OF SLEET AND EITHER
END OR BE A SLIGHT DZ/FLURRIES.
THINK BEST CHANCES FOR SNOW WILL BE OVER THE W IN THE EVENING...AS
THE COLD AIR ALLOWS FOR LK ENHANCEMENT WITH H900-875 TEMPS FALLING
TO -8C. CLOUD DEPTH SHOULD BE LIMITED WITH THE INVERSION AROUND H850
OR 3KFT. THUS...WILL MAINLY BE FLURRIES OR LIGHT SNOW SHOWERS AND
LINGERED CHANCES/SLIGHTS OVER THE NW FAVORED LOCATIONS IN THE W
THROUGH THE EARLY OVERNIGHT HRS. DRY LLVL AIR WILL THEN QUICKLY WORK
IN OVERNIGHT...SO HAVE DIMINISHED THE LINGERING POPS QUICKLY FROM W
TO E NEAR LK SUPERIOR.
THERE IS SOME POTENTIAL FOR CLEARING OVER THE INTERIOR W LATE IN THE
NIGHT...WHICH COULD ALLOW TEMPS TO FALL BELOW GUIDANCE WITH PWAT
VALUES AROUND 55 PERCENT OF NORMAL. WINDS WILL BE DIMINISHING WITH
THE APPROACHING SFC RIDGE...BUT MAY NOT ARRIVE EARLY ENOUGH TO
MAXIMIZE THE RADIATIONAL COOLING. WILL HIGHLIGHT THE COLDEST VALUES
NEAR WATERSMEET WITH LOWS IN THE UPPER TEENS.
UPPER TROUGH WILL BE MOVING OVER THE UPPER GREAT LAKES THROUGH
THE DAY ON THURS...ALLOWING SFC LOW TO DEVELOP OVER SRN ONTARIO
THURS AFTN AND INTENSIFY AS IT MOVES SE ON THURS NIGHT. DRY AIR
ABOVE H850 BEHIND THE FRONT WILL BE PUSHING FROM NW TO SE ACROSS THE
AREA THURS MORN AHEAD OF SECONDARY TROUGH BRINGING DEEPER MOISTURE
AND COLDER AIR. THINK THIS WILL LEAD TO A PERIOD OF PARTLY CLOUDY
TO MOSTLY SUNNY SKY OVER MUCH OF THE CWA IN THE MORNING. THEN...AS
THE TROUGH MOVES INTO THE AREA AND BRINGS DEEPER MOISTURE AND
H850-700 Q-VECTOR CONV...HAVE INCREASED CLOUDS AND BRING
SLIGHT/CHANCES OF SNOW BACK IN THE AFTN NEAR LK SUPERIOR.
UPPER TROUGH WILL START TO PUSH E ON THURS NIGHT AND CONTINUE E ON
FRI...AS RIDGING STARTS TO MOVE OVER THE AREA AND SFC HIGH PUSHES
INTO THE WRN GREAT LKS. WITH SECONDARY COLD FRONT DROPPING SE
ACROSS LK SUPERIOR...EXPECT ADDITIONAL LLVL MOISTURE AND FALLING
H850 TEMPS TOWARDS -13C TO LEAD TO INCREASING LAKE
EFFECT/ENHANCEMENT FOR AREAS NEAR LK SUPERIOR. WITH THE STRONG NW
AND THEN NNW WINDS...EXPECT CLOUD COVER TO SPREAD ACROSS MUCH OF
THE AREA THURS NIGHT AND CONTINUE INTO FRI MORNING. WITH THE COLD
AIR SPILLING IN...EXPECT GUSTY WINDS AS H925 WINDS TO 35KTS OVER THE
NE HALF OF THE CWA TO MIX TO THE SFC AND PRODUCE 25-35KT GUSTS NEAR
LK SUPERIOR E OF MARQUETTE. OVERALL...DON/T EXPECT TOO MUCH SNOW
ACCUM AS THE PERIOD OF FAVORABLE CONDITIONS IT FAIRLY LIMITED ON
THURS NIGHT...BEFORE DRIER AIR ARRIVES AND LOWERING INVERSION
HEADING THROUGH THE DAY ON FRI. IN ADDITION...WITH THE INCREASING
H850 WAA ON FRI AFTN OVER THE WRN LK WILL ALSO AID TO END THE
LINGERING LES FROM W TO E THROUGH THE DAY FRI. ALL IN
ALL...THURS AND FRI LOOK TO BE A PERIOD OF NORMAL TO BELOW
NORMAL TEMPS ACROSS THE AREA AHEAD OF THE POTENTIAL WARM-UP FOR
THE WEEKEND INTO NEXT WEEK.
DAYS 4 THROUGH 7 /FRI NIGHT THROUGH TUESDAY/...
UPPER LOW SPINNING OVER THE FOUR CORNERS REGION ON FRI NIGHT WILL
BEGIN TO GET CAUGHT UP WITH THE FLOW AND DRIFT NNE.
MEANWHILE...NEARLY ZONAL FLOW NRN STREAM LOOKS TO BE SETUP OVER SRN
CANADA...KEEPING THE COLD AIR WELL N OF THE UPPER GREAT LKS.
12Z RUNS CONTINUE THE DIFFERENCES WITH THE TRACK OF THE
UPPER LOW. HPC PREFERS A CONSENSUS SOLN NOT INCLUDING THE
GFS...WHICH TRACKS THE LOW MUCH FASTER AND FARTHER SE. 12Z RUN IS
THE SAME AND REMAINS VERY CONSISTENT OVER THE LAST SEVERAL
RUNS...WHICH COULD LEAD SOME CREDIT TO THE THAT SOLN. ENS MEAN ON
ECMWF/GEM IS A LITTLE SLOWER THAN THE DETERMINISTIC RUN...BUT
FOLLOWS A SIMILAR TRACK. OVERALL CONSENSUS PULLS THE UPPER LOW
THROUGH THE GREAT LKS REGION SUN INTO MON. WILL CONTINUE TO MENTION
CHANCE POPS ACROSS THE AREA...WHICH SHOULD FALL AS RAIN DUE TO THE
WARM AIR ALREADY IN PLACE.
EXTENDED MODELS CONTINUE TO SHOW THE POTENTIAL FOR A BIG WARM UP
BEHIND THE UPPER LOW THAT MOVES THROUGH THE GREAT LKS. AMPLIFYING
AND NEARLY STATIONARY TROUGH OFF THE W COAST OF THE CONUS WILL LEAD
TO AMPLIFYING RIDGE OVER THE CANADIAN PRAIRIES. THIS WILL ALLOW SFC
HIGH TO BE STATIONED OVER THE ERN CONUS AND WITH THE MAIN LOWS
TRACKING WELL TO THE N THROUGH CANADA...EXPECT SRLY FLOW TO BE SETUP
OVER THE CWA. CONSENSUS OF THE MODELS GIVES VALUES IN THE 40S AND
NEAR 50 ALONG THE WI BORDER FOR HIGHS ON TUES. THIS IS USUALLY UNDER
DONE IN WELL ABOVE NORMAL SITUATIONS AND THE ECMWF /WHICH ALMOST
ALWAYS VERIFIES THE BEST IN THESE ABOVE NORMAL SITUATIONS/ HAS
VALUES ABOUT 7-10 DEGREES WARMER THAN THE CONSENSUS. THE TEMPS LOOK
TO GET EVEN WARMER HEADING INTO WED/THURS. ECMWF HAS TEMPS FOR
WED/THURS OF NEXT WEEK OVER THE W HALF IN THE 60S WITH COOLER TEMPS
NEAR LK MI WITH THE SSW FLOW. ECMWF EVEN ATTEMPTS TO TRY AN PUSH A
FEW 70S ALONG THE WI BORDER.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 626 PM EST TUE MAR 6 2012
VFR CONDITIONS WILL PREVAIL AT ALL 3 SITES THRU AT LEAST EARLY
EVENING. INCREASING LOW-LEVEL MOISTURE OVER SNOWPACK SHOULD RESULT
IN LOW CLOUDS/FOG DEVELOPING TONIGHT...WITH BEST CHC OF LOW
MVFR/POSSIBLE IFR CIG AT KSAW DUE TO UPSLOPE COMPONENT TO S WIND.
DOWNSLOPE NATURE OF S WIND AT KIWD/KCMX SHOULD HELP TO MAINTAIN VFR
CONDITIONS AT THOSE SITES. WITH FAIRLY STRONG WINDS ABOVE LOW-LEVEL
INVERSION...EXPECT LLWS TONIGHT. IFR CONDITIONS ARE LIKELY TO
DEVELOP AT ALL SITES WED MORNING AS LOW-LEVEL MOISTURE CONTINUES TO
INCREASE AHEAD OF APPROACHING COLD FRONT. A DISTURBANCE MOVING NEWD
ALONG THIS FRONT WILL BRING A BETTER CHANCE OF -RA AND LIFR
CONDITIONS COINCIDENT WITH AND FOLLOWING THE FROPA AS THE -RA
CHANGES TO -SN AT LEAST AT THE WESTERN SITES WITH THE RETURN OF
COLDER AIR.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 405 PM EST TUE MAR 6 2012
SOUTHERLY WINDS OF 20-30KT OVER ERN LAKE SUPERIOR (LIGHTER OVER THE
W) AHEAD OF AN APPROACHING COLD FRONT WILL SLOWLY DIMINISH TONIGHT.
WINDS SHOULD MOSTLY DROP OFF BLO 20KT FOR MUCH OF WED AS THE COLD
FRONT ARRIVES. WITH THE PASSAGE OF COLD FRONT...NW WINDS WILL BE ON
THE INCREASE WED EVENING AND THEN THRU THU AS A FOLLOWING LOW PRES
CENTER PASSES SE ACROSS NRN ONTARIO. UNDER CAA/INCREASING OVERWATER
INSTABILITY...NW WINDS WILL INCREASE TO 20-30KT...ESPECIALLY THU/THU
NIGHT. GALES ARE A POSSIBILITY. WINDS WILL DIMINISH TO UNDER 20KT BY
LATE FRIDAY AFTN AS HIGH PRESSURE BUILDS INTO THE REGION. ON THE
BACKSIDE OF THE HIGH...SW WINDS WILL RAMP BACK UP TO 20-30KT SAT.
&&
.HYDROLOGY...
ISSUED AT 405 PM EST TUE MAR 6 2012
EVEN WITH THE WARM TEMPS OVER THE NEXT 24-36 HOURS...DON/T EXPECT
MUCH IF ANY MELTING TO OCCUR DUE TO THE UN-RIPE CONDITIONS OF THE
SNOW PACK. LOOKING AT NOHRSC CURRENT AND FUTURE SNOWPACK
TEMPERATURES...ONLY THE TOP AND MIDDLE LAYERS /TOP 2-10 INCHES
DEPENDING ON LOCATION/ OF THE SNOWPACK BECOME RIPE OVER THE SW HALF
OF THE CWA BY WED EVENING. THIS WILL LIKELY LEAD TO SOME
COMPACTION/MELTING OF THE TOP OF THE EXISTING SNOWPACK...BUT IT
SHOULD STILL RETAIN THE WATER AND KEEP MUCH OR ALL OF THE MOISTURE
IN THE SNOWPACK THROUGH WED EVENING.
WITH COOLER TEMPERATURES EXPECTED BEHIND THE COLD FRONT ON
WED...DON/T EXPECT ANY MELTING TO OCCUR WED NIGHT INTO SAT. WITH THE
WARMING TREND EXPECTED DURING THE WEEKEND AND INTO NEXT WEEK...WILL
NEED TO KEEP AN EYE ON A SLOWLY RIPENING SNOWPACK. THE POTENTIAL FOR
RAIN ON SUN/MON MAY ASSIST IN THIS RIPENING THROUGH THE FIRST PART
OF NEXT WEEK.
THE POTENTIAL FOR MELTING OF THE SNOWPACK COULD GREATLY INCREASE
HEADING INTO THE MIDDLE OF NEXT WEEK...AS OVERNIGHT LOWS AND TD
VALUES RISE ABOVE FREEZING. THE EXTENDED MODELS HAVE BEEN SHOWING
WELL ABOVE NORMAL TEMPERATURES /10 PLUS DEGREES/ FOR THE MIDDLE OF
NEXT WEEK. IF THE WARM TEMPS SHOWN ON THE ECMWF /HIGHS IN THE 60S
FOR WED AND THURS/ COME TO FRUITION...THE MELT MAY BE FAIRLY FAST
AND RUN OFF DIRECTLY INTO AREA RIVERS. THUS...WILL NEED TO KEEP AN
EYE ON AREA RIVERS AND STREAMS NEXT WEEK FOR THE POTENTIAL OF RISING
LEVELS DUE TO SNOWMELT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...ROLFSON
SHORT TERM...ROLFSON
LONG TERM...SRF
AVIATION...KC
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1130 PM CST SUN MAR 4 2012
.AVIATION...06Z TAF. MAIN CONCERN FOR THE FORECAST WILL BE WINDS.
LIGHT AND VARIABLE WINDS ARE EXPECTED TONIGHT AS HIGH PRESSURE
MOVES THROUGH THE AREA...BUT WINDS WILL TURN TO THE SOUTH BY
MORNING AND INCREASE DURING THE MORNING INTO THE AFTERNOON. GUSTY
SOUTH WINDS ARE EXPECTED FOR THE AFTERNOON THEN SHOULD DIMINISH
SOME AFTER THE SUN GOES DOWN. SKIES SHOULD BE MAINLY CLEAR BUT
THERE COULD BE A FEW CUMULUS DURING THE AFTERNOON...BUT THEY WILL
BE VFR.
&&
.PREV DISCUSSION... /ISSUED 624 PM CST SUN MAR 4 2012/
UPDATE...WINDS HAVE STARTED TO DIMINISH AND THE WIND ADVISORY HAS
BEEN ALLOWED TO EXPIRE.
PREV DISCUSSION... /ISSUED 344 PM CST SUN MAR 4 2012/
SHORT TERM...THROUGH 00Z TUESDAY. MORNING UPPER AIR ANALYSIS INDICATES
LONG WAVE RIDGING OVER THE WESTERN CONUS AND TROUGHING OVER THE
EAST. MID AND UPPER LEVEL JET ENERGY IS POSITIONED OVER THE
CENTRAL PLAINS AS A RESULT. FLOW REMAINS VERY STRONG THROUGH LOWER
PORTIONS OF THE TROPOSPHERE AS WELL...WITH A ~50KT 700MB JET
STREAK AND A ~40KT 850MB JET STREAK CURRENTLY OVER PORTIONS OF THE
CENTRAL PLAINS. WATER VAPOR IMAGERY INDICATES INCREASING MID LEVEL
MOISTURE ACROSS MUCH OF THE CENTRAL CONUS ALONG THE MID LEVEL JET
AXIS. AT THE SURFACE A WEAK AREA OF LOW PRESSURE IS SITUATED OVER
THE MISSOURI VALLEY...WITH LOW LEVEL FLOW REMAINING FROM THE
NORTHWEST ACROSS MUCH OF OUR AREA AS A RESULT.
PROXIMITY SOUNDINGS FROM LAPS AND RUC ANALYSIS SUGGEST BOUNDARY
LAYER MIXING TO BETWEEN 750MB AND 700MB PERSISTS AT THIS HOUR ACROSS
MUCH OF OUR CWA...A TREND WHICH WILL CONTINUE UNTIL DIABATIC HEATING
IS LOST LATER THIS EVENING. ALSO...AS MENTIONED ABOVE...RUC ANALYSIS
INDICATES A 700MB JET STREAK OF ~50KTS AND AN 850MB JET STREAK OF
~40KTS ALSO PERSISTS OVER THE AREA. SUSTAINED WINDS OF 20KTS TO NEAR
35KTS...WITH GUSTS AROUND 40KTS...CONTINUE ACROSS MUCH OF THE CWA
AS A RESULT. ALTHOUGH WIND ADVISORY WINDS ARE NOT AS PREVALENT
FARTHER SOUTH/SOUTHWEST ACROSS OUR CWA...KMCK CONTINUES TO REPORT
STRONG WINDS...SOME OF WHICH COULD SLIP INTO KHDE AND KPHG TOWARDS
LATE AFTERNOON. GIVEN ALL THIS...WILL CONTINUE THE CURRENT WIND
ADVISORY THROUGH 00Z. THESE WINDS SHOULD SUBSIDE VERY QUICKLY AROUND
SUNSET AS DIABATIC HEATING IS LOST AND THE BOUNDARY LAYER IS
DECOUPLED FROM THE STRONGER WINDS ALOFT.
ALTHOUGH THE MID AND UPPER LEVEL JET AXIS IS OVER US KNOW...IT HAS
BEGUN TO DRIFT EAST...AWAY FROM OUR AREA. MID AND UPPER LEVEL JET
ENERGY SHOULD MOVE COMPLETELY OUT OF OUR AREA TONIGHT...THUS
PRESENTING LITTLE TO NO KINEMATIC FORCING ACROSS OUR AREA THROUGH
THE REMAINDER OF THE SHORT TERM FORECAST PERIOD. DRY CONDITIONS ARE
FORECAST TONIGHT AND TOMORROW AS A RESULT.
FORECAST PROXIMITY SOUNDINGS FROM THE NAM AND OPERATIONAL GFS
SUGGEST BOUNDARY LAYER MIXING TO AROUND 800MB...IF NOT SLIGHTLY
DEEPER...WILL BE REALIZED ACROSS THE CWA MONDAY AFTERNOON. AS THE
MID LEVEL JET AXIS SHIFTS EAST INTO THE MISSISSIPPI VALLEY SO WILL
THE MID LEVEL MOISTURE PLUME...THUS ELIMINATING THE INCREASED RH
VALUES WE HAVE SEEN AT THE TOP OF THE MIXED LAYER BOTH TODAY AND
YESTERDAY. THIS WILL IN TURN PRESENT AN OPPORTUNITY FOR AFTERNOON
SURFACE DEW POINTS TO DROP OFF AS BOUNDARY LAYER MIXING COMMENCES
MONDAY AFTERNOON. THANKFULLY...A STIFF SOUTHERLY LOW LEVEL WIND
FIELD...PERHAPS TURNING A TOUCH SOUTHWESTERLY BY MID TO LATE
AFTERNOON BUT NOT BY MUCH...SHOULD HELP PROMOTE DESCENT LOW LEVEL
MOISTURE INFLUX TO OUR AREA. THIS SHOULD HELP OFFSET AFTERNOON DROPS
IN DEW POINTS. ALL THAT BEING SAID...THE CURRENT FORECAST SHOWS MONDAY
AFTERNOON SURFACE RH VALUES DROPPING TO AROUND 21% FOR A COUPLE
HOURS ACROSS OUR EXTREME SOUTHWEST. THIS LOOKS LIKE A MARGINAL RFW
EVENT FOR EXTREME SOUTHWESTERN PORTIONS OF OUR CWA MONDAY. WILL
HOLD OFF ON ANY FIRE WEATHER HEADLINES FOR MONDAY AND LET THE
EVENING AND OVERNIGHT SHIFTS EVALUATE FURTHER. WILL HOWEVER GO
AHEAD AND MENTION AN ELEVATED FIRE WEATHER THREAT IN THE HWO TO
GET THE WORD OUT.
THE AFOREMENTIONED BOUNDARY LAYER MIXING ON MONDAY...WORKING IN
CONCERT WITH A STRENGTHENING LOW LEVEL PRESSURE GRADIENT DUE TO AN
INTENSIFYING LEE SIDE TROUGH ACROSS THE FRONT RANGE...WILL PRESENT
YET ANOTHER BREEZY DAY ACROSS THE CWA. MAV GUIDANCE SUGGESTS OUR
EXTREME SOUTH WILL BRIEFLY HIT WIND ADVISORY THRESHOLDS BY MID
AFTERNOON...WHILE THE MET GUIDANCE KEEPS OUR ENTIRE CWA UNDER WIND
ADVISORY THRESHOLDS. WILL KEEP ANY MENTION OF WIND ADVISORY WINDS
OUT OF THE FORECAST FOR NOW...BUT MENTION INCREASED WINDS ACROSS OUR
SOUTH IN THE HWO TO GET THE WORD OUT. FUTURE SHIFTS WILL CERTAINLY WANT
TO KEEP A CLOSE EYE ON MONDAY WINDS TO MAKE SURE THEY WILL INDEED
REMAIN BELOW ADVISORY LEVELS.
LONG TERM...MONDAY NIGHT THROUGH SUNDAY. DRY...QUIET WEATHER WILL
BE IN PLACE MONDAY NIGHT IN A FAIRLY ZONAL PATTERN ALOFT...FOLLOWING
PASSAGE OF SURFACE TROUGH. WARM FRONTAL BOUNDARY LIFTS WELL NORTH
INTO THE DAKOTAS ON TUESDAY AND MODELS ARE CONSISTENT THAT
UNSEASONABLY MILD H85 TEMPS OF 14C TO 15C WILL SETTLE ACROSS THE
INTERIOR CONUS. FORECAST SOUNDINGS SUGGEST MIXING WILL REACH H85
AND SUBSEQUENT HIGH TEMPS SHLD EASILY REACH THE 70S. TUESDAY WILL
NOT BE WITHOUT WIND HOWEVER...WITH FORECAST SOUNDINGS SHOWING WINDS
AT THE TOP OF THE MIXED LAYER RANGING FROM AROUND 17KTS IN OUR WEST
TO OVER 30KTS IN THE EAST. SURFACE GRADIENT IS TIGHTEST IN THE EAST
AND CONDITIONS ARE LOOKING BORDERLINE FOR REACHING WIND ADVISORY
CRITERIA ATTM. CURRENTLY HAVE A FIRE WEATHER WATCH FOR OUR WESTERN
CWA FOR TUESDAY...AND WITH FRONT SLOWING DOWN...WINDS LOOK STRONGER
IN OUR WEST COMPARED TO 24HRS AGO. PROGGED RH VALUES DROP BELOW 20
PERCENT ALONG THE WESTERN PERIPHERY OF OUR CWA...AND WILL LEAVE
CURRENT WATCH HEADLINE AS IS. IF FRONT CONTINUES TO SLOW...HIGHER
DPS MAY MATERIALIZE AS WELL AS HIGHER RH/S. WILL CONTINUE TO
MONITOR.
UPPER TROUGH MOVES INTO THE ROCKIES TUESDAY NIGHT WITH THE SOUTHERN
STREAM CLOSING/CUTTING OFF ON WEDNESDAY...WHILE THE NORTHERN STREAM
TRANSLATES ACROSS THE DAKOTAS/UPPER MIDWEST. THE ASSOCIATED COLD
FRONT WITH NORTHERN SYSTEM GRADUALLY PUSHES SOUTH INTO OUR CWA
OVERNIGHT INTO WEDNESDAY MORNING. THE GFS IS FASTER WITH FRONT THAN
THE NAM AND HAVE TRENDED TOWARD THE SLOWER SOLUTION. FRONTOGENETIC
FORCING INCREASES ALONG BOUNDARY...MAINLY IN THE AFTN...AND WITH
SLOWER TIMING/INCREASING FORCING HAVE EXPANDED POPS TO OUR ENTIRE
CWA. INSTABILITY PROGS SHOW SOME MUCAPE WITH NAM INDICATING VALUES
GENERALLY 25J/KG WITH GFS AS HIGH AS 200 J/K IN OUR FAR SOUTHEAST.
WILL GO WITH CONVECTIVE RAIN SHOWER WORDING FOR NOW AND MONITOR
INSTABILITY TRENDS BEFORE INSERTING THUNDER JUST YET. COLD AIR
ADVECTS SOUTH BEHIND FRONT WITH NW WINDS INCREASING FOR A TIME ON
WED. PCPN CHCS CONTINUES WED NIGHT AND INTO THURSDAY BUT SHIFT
SOUTH WITH TIME ALONG SOUTHWARD ADVANCING BAROCLINIC ZONE. AS TEMPS
DIURNALLY COOL...A MIX OF R/S IS POSSIBLE.
FROM THE LATTER PART OF THE WEEK AND INTO THE WEEKEND MODELS DIVERGE
IN HANDLING OF THE SOUTHWEST CONUS CUTOFF UPPER LOW PRESSURE
SYSTEM. CONFIDENCE REMAINS LOW DURING THIS TIME FRAME GIVEN THE
VARYING SOLUTIONS.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...FIRE WEATHER WATCH TUESDAY AFTERNOON FOR NEZ060-072-073-082-083.
KS...FIRE WEATHER WATCH TUESDAY AFTERNOON FOR KSZ005-017.
&&
$$
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
101 PM EST MON MAR 5 2012
.SYNOPSIS...
AN AREA OF LOW PRESSURE WILL MOVE RAPIDLY EAST ACROSS NORTH CAROLINA
TODAY. STRONG HIGH PRESSURE WILL BUILD OVER THE REGION TUESDAY
AND THEN MOVE OFFSHORE WEDNESDAY AND THURSDAY. A COLD FRONT WILL
MOVE ACROSS THE AREA FRIDAY NIGHT. HIGH PRESSURE WILL BUILD INTO
THE AREA FROM THE NORTH SATURDAY AND SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 100 PM MON...WIND ADVISORY REMAINS INTACT THROUGH THE REST
OF THE AFTERNOON. OCNL GUSTS TO 45 KT ACROSS OBX AND DOWNEAST
CARTERET...WITH GUSTS NEARING 40 KT SOME AREAS INLAND. 3 HR PRES
RISES OF 4 MB THROUGH MID AFTERNOON PER LATEST RUC GUIDANCE
INDICATE GUSTY WINDS WILL PERIST THRUOGH THIS TIME PERIOD...BEFORE
ABATING IN THE LATE AFTERNOON. WINDS SHOULD DIMINISH QUITE RAPIDLY
TOWARDS SUNSET AS GRADIENT RELAXES AND LOSS OF SOLAR INSOLATION.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
AS OF 335 AM MON...HIGH PRESSURE BUILDS EAST ACROSS EASTERN NC
TONIGHT WITH WINDS VEERING NORTHWEST AND EVENTUALLY NORTH. TEMPS
WILL FALL INTO THE UPPER 20S INLAND TO LOWER 30S ALONG THE
COAST...WITH MID 30S ALONG THE OBX. OVERALL DRY AIRMASS AND LIGHT
NORTHERLY FLOW SHOULD INHIBIT FOG DEVELOPMENT...HOWEVER STRONG
SURFACE BASED INVERSION WILL DEVELOP WHICH MAY DECOUPLE WINDS LONG
ENOUGH FOR SOME SHALLOW/BRIEF DITCH FOG TO FORM ESPECIALLY GIVEN
THE RECENT RAINS/SATURATED SOILS.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
AS OF 330 AM MONDAY...NO SIGNIFICANT CHANGES TO PREVIOUS FCST DURING
PERIOD WITH DECENT MODEL CONSISTENCY AND CONTINUITY INDICATED. COOL
SFC HIGH PRES WILL PRODUCE FAIR SKIES BUT BELOW NORMAL TEMPS TUE AND
TUE NIGHT...THEN RIDGING ALOFT WITH SFC HIGH EXTENDING OVER AREA
FROM OFFSHORE WILL PRODUCE MODERATING TEMPS WITH READING 10-15 DEGS
ABOVE NORMAL FOR THU-FRI. WILL SEE SOME INCREASE IN CLOUD COVER WITH
RETURN SRLY FLOW STARTING ON WED...BUT PCPN THREAT WILL HOLD OFF
UNTIL FRONTAL BNDRY PUSHES IN FRI-SAT.
SOME TIMING DIFFERENCES CONTINUE WITH LATEST GFS AND ECMWF WITH
HANDLING OF UPR LOW CUTTING OFF OVER SW US...BUT BOTH INDICATE NRN
STREAM SYSTEM WILL PUSH FRONT THROUGH AREA LATE FRI INTO EARLY SAT.
THIS IS IN LINE WITH PREVIOUS FCST THINKING ON POPS.
MINOR ADJUSTMENTS TO TEMPS FOR WED-FRI BASED ON LATEST GDNC. MAX
TEMPS INTO MID 70S FRIDAY FOR INLAND SECTIONS AHEAD OF FRONT.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
SHORT TERM /THROUGH MONDAY/...
AS OF 1 PM MONDAY...BIG STORY FOR THE TAF CYCLE WILL BE THE GUSTY
WINDS THROUGH THE AFTERNOON HOURS TODAY. TIGHT PRES GRADIENT WITH
DEPARTING LOW AND EFFICIENT MIXING FROM ALOFT WILL ALLOW FOR WINDS
TO GUST TO ABOVE 30 KT. BKN TO SCT 8K FT DECK WILL LINGER UNTIL
SUNSET...BEFORE CLEARING THIS EVENING WITH LOSS OF DAYTIME
HEATING. WINDS WILL ALSO DIMINISH RAPIDLY BY SUNSET...BECOMING
LIGHT OVERNIGHT. WINDS WILL BE NORTH TO NORTHEAST GENERALLY BELOW
10 KTS FOR TUE MORNING INTO EARLY AFTERNOON.
LONG TERM MONDAY NIGHT THROUGH FRIDAY/...
AS OF 330 AM MONDAY...VFR CONDITIONS EXPECTED INTO EARLY FRIDAY AS A
LARGE AND STRONG HIGH PRESSURE SYSTEM INFLUENCES THE WEATHER.
MOISTURE ASSOCIATED WITH AN APPROACHING COLD FRONT COULD LEAD TO THE
DEVELOPMENT OF SHOWER ACTIVITY AND SUB VFR CONDITIONS LATE FRIDAY.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 900 AM MON...ADDED PAMLICO SOUND TO GALE WARNING...AS
FURTHER NORTH LOW TRACK WILL ALLOW FOR BETTER GRADIENT SOUTHWEST WINDS
TO AFFECT THE SOUND. WINDS AND WAVES HIGHEST ACROSS EASTERN
PORTIONS OF PAMLICO.
AS OF 345 AM SUN...LATEST SURFACE AND BUOY OBSERVATIONS INDICATE
SOUTH-SOUTHWESTERLY WINDS 10 TO 20 KNOTS WITH SEAS 4 TO 7 FT FROM DUCK
SOUTH TO OFF ONSLOW BAY. WINDS WILL INCREASE THIS MORNING
ASSOCIATED WITH A CLIPPER LOW WHICH WILL CROSS THE WATERS BETWEEN
15-21Z. GALE FORCE WINDS ARE EXPECTED ACROSS THE SOUTHERN AND
CENTRAL WATERS...BEFORE VEERING NORTHWEST AND SLOWLY DIMINISHING
LATE THIS EVENING. GALE WARNINGS WILL LIKELY BE REPLACED BY AN
SCA AFTER THE 00Z EXP TIME. ADDED ALBEMARLE SOUND TO SCA GIVEN
EASTERN PORTIONS WILL LIKELY SEE FREQUENT GUSTS ABOVE 25 KNOTS AS
THE LOW CROSSES. WINDS WILL VEER NORTHWEST BEHIND THE LOW LATE
TODAY...THEN SHIFT NORTHERLY NEAR SUNRISE. WAVES WILL PEAK 8-11 FT
THIS AFTERNOON...THEN SUBSIDE 6-9 FT THROUGH THE EVENING BEFORE
FALLING OUT TO 5-7 FT OVERNIGHT. SWAN AND WAVEWATCH III WERE IN
FAIRLY CLOSE AGREEMENT FOR THE SHORT TERM.
/LONG TERM MONDAY NIGHT THROUGH FRIDAY/...
AS OF 340 AM MONDAY...WINDS AND SEAS EXPECTED TO DIMINISH BELOW SCA
CRITERIA BY TUE AFTN AS LARGE HIGH PRES CENTER BUILDS OVER AREA.
HIGH WILL THEN EXTEND OVER AREA FROM OFFSHORE THROUGH END OF WEEK
WITH WINDS GRADUALLY VEERING BACK TO SRLY DURING PERIOD. SPEEDS
GENERALLY LESS THAN 15 KTS UNTIL FRIDAY WHEN PRES GRAD WILL TIGHTEN
AHEAD OF NEXT FRONT.
NO CHANGES TO PREVIOUS FCST SEAS DURING PERIOD. HEIGHTS WILL
GRADUALLY FALL TO 3 FT OR LESS BY TUE EVENING. SOME INCREASE TO 3-4
FT EXPECTED SRN WATERS WITH RETURN SRLY FLOW THU...THEN 4-5 FT
FRIDAY WITH INCREASING WINDS.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...WIND ADVISORY UNTIL 6 PM EST THIS EVENING FOR NCZ029-044>047-
079>081-090>094-098.
WIND ADVISORY UNTIL 10 PM EST THIS EVENING FOR NCZ095-103-104.
MARINE...GALE WARNING UNTIL 7 PM EST THIS EVENING FOR AMZ135-152-154-
156-158.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR AMZ130.
SMALL CRAFT ADVISORY UNTIL 11 AM EST TUESDAY FOR AMZ150.
&&
$$
SYNOPSIS...DAG
NEAR TERM...TL
SHORT TERM...DAG
LONG TERM...JBM
AVIATION...TL/JBM
MARINE...TL/DAG/JBM
AREA FORECAST DISCUSSION
NWS RALEIGH NC
121 AM EST MON MAR 5 2012
.SYNOPSIS...
A FAST MOVING CLIPPER LOW WILL TRACK EASTWARD ALONG THE NORTH
CAROLINA AND VIRGINIA BORDER LATE TONIGHT THROUGH MONDAY MORNING...
BEFORE MOVING OFFSHORE EARLY MONDAY AFTERNOON. DRY HIGH PRESSURE
WILL BUILD OVER THE CAROLINAS MONDAY NIGHT THROUGH MID WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
AS OF 930 PM SUNDAY...
A WINTER WEATHER ADVISORY REMAINS IN EFFECT FOR THE ADJACENT
VIRGINIA BORDERING COUNTIES ACROSS THE CENTRAL PIEDMONT AND NORTHERN
COASTAL PLAIN FROM 4AM TO NOON MONDAY.
NO SIGNIFICANT CHANGES TO THE FORECAST TONIGHT AS MODELS CONTINUE TO
BE IN GOOD AGREEMENT WITH UPSTREAM OBSERVATIONS. THE UPPER LEVEL
JET MAXIMA AND ASSOCIATED SHEAR VORTICITY ARE CURRENTLY DIGGING
SOUTHEAST INTO SOUTHERN ILLINOIS...AND PRECIPITATION HAS BEGUN TO
EXPAND FROM AROUND PEORIA SOUTH TO NASHVILLE. THE SURFACE LOW
WAS ANALYZED NEAR THE MISSOURI/ILLINOIS/KENTUCKY BORDER
AREA...AGAIN IN GOOD AGREEMENT WITH WHERE 12Z AND 18Z MODELS
PROJECTED. THE NEW 00Z/05 NAM SHOWS THE TRACK OF THE SURFACE LOW
NORTH OF ITS 18Z/04 RUNS...WITH THE LOW TRACKING CLOSER TO THE
NORTH CAROLINA/VIRGINIA BORDER...AND THE FORECAST QPF ACCORDINGLY
IS LESS ALONG THE VIRGINIA BORDER COUNTIES. THIS IS SUPPORTED BY
THE 00Z/05 RUC ALSO. HOWEVER...MODELS HAVE BEEN FAIRLY CONSISTENT
UP TO THIS POINT... SO WE WILL NOT ADJUST THE ADVISORY AND WILL
ONLY MAKE SMALL REDUCTIONS IN QPF AND SNOW TOTALS. SOUTH OF WHERE
THE LOW LEVEL FGEN BAND SETS UP... STEEP 850-700MB LAPSE RATES
WILL SUPPORT QUICK INSTABILITY RAIN/SNOW SHOWERS...BUT SHORTER
DURATION AND SUBLIMATION SHOULD PREVENT MUCH ACCUMULATION ALONG
THE INTERSTATE 40 TO HIGHWAY 64 CORRIDORS JUST SOUTH OF THE
ADVISORY.
TEMPERATURES ARE ALREADY IN THE UPPER 30S TO LOWER 40S ACROSS THE
AREA...BUT SURFACE WINDS ARE BEGINNING TO STIR OUT OF THE SOUTHWEST
AND MID LEVEL CLOUD COVER ASSOCIATED WITH THE CLIPPER SYSTEM IS
RAPIDLY APPROACHING. TEMPERATURES SHOULD BE ABLE TO FALL A FEW MORE
DEGREES...BUT LOW 30S MAY NOT BE ATTAINABLE IN SOME WESTERN AREAS.
THE LOW WILL QUICKLY MOVE OFF THE OUTER BANKS BY MIDDAY...WITH
STRONG SUBSIDENCE AND COLD DRY AIR ADVECTION CLEARING SKIES FROM
WEST TO EAST...WITH BREEZY NORTHWEST WIND GUSTS OF 25 KNOTS IN
THE WAKE OF THE EXITING CLIPPER LOW. CONSIDERABLE SUNSHINE DURING
THE AFTERNOON AND TEMPERATURES IN THE LOWER TO MID 40S NORTH TO
MID 50S SOUTH WILL GO A LONG WAY IN MELTING ANY SNOW ACROSS THE
ADVISORY AREA.
&&
.SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/...
AS OF 300 PM SUNDAY...
TO START THE SHORT TERM PERIOD...A STRONG CLIPPER SYSTEM WILL BE
DEPARTING THE REGION...WITH FAIRLY STRONG SURFACE HIGH PRESSURE
(AROUND 1035 MILLIBARS) BUILDING IN BEHIND IT AND THEN PERSISTING
OVER THE REGION FOR THE REMAINDER OF THE PERIOD. AM EXPECTING
EXCELLENT RADIATIONAL CONDITIONS FOR MONDAY NIGHT AS THE SURFACE
HIGH IS FORECAST TO BE CENTERED DIRECTLY OVER THE FORECAST AREA
BY 12Z TUESDAY MORNING. OVERNIGHT LOWS ARE EXPECTED TO GENERALLY
BE IN THE MID 20S AREA WIDE MONDAY NIGHT. THIS CHILLY HIGH PRESSURE
SHOULD REMAIN OVER THE AREA FOR MOST OF THE DAY ON TUESDAY NOT
ALLOWING FOR MUCH IN THE WAY OF TEMPERATURE MODERATION. THEREFORE...
AM EXPECTING BELOW NORMAL TEMPERATURES ON TUESDAY... WITH
TEMPERATURES ONLY RISING INTO THE LOW TO MID 50S. OVERNIGHT LOWS
WILL ONLY MODERATE SLIGHTLY ON TUESDAY NIGHT AS THE HIGH GRADUALLY
BEGINS TO SHIFT OFFSHORE. HOWEVER...SKIES WILL STILL BE MOSTLY
CLEAR AND WINDS WILL BE LIGHT...LEADING TO ANOTHER NIGHT OF GOOD
RADIATIONAL COOLING CONDITIONS. THEREFORE...AM EXPECTING LOWS IN
THE UPPER 20S TO LOWER 30S.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
AS OF 300 PM SUNDAY...
UPPER LEVEL RIDGING WILL PERSIST OVER THE REGION THROUGH THE END OF
THE WORK WEEK....WHILE AS THE SURFACE...HIGH PRESSURE IS FORECAST TO
SHIFT OFFSHORE ON WEDNESDAY...BUT CONTINUE TO RIDGE INTO THE AREA
THROUGH AT LEAST THE END OF THE WORK WEEK. THIS WILL RESULT IN
RETURN FLOW SETTING UP AT THE LOW LEVELS AND THEREFORE A GRADUAL
MODERATION OF TEMPERATURES AS WELL AS A GRADUAL INCREASE IN CLOUD
COVER. HIGHS ARE EXPECTED TO MODERATE FROM THE MID 60S ON
WEDNESDAY TO THE LOWER 70S BY FRIDAY...WHILE OVERNIGHT LOWS WILL
GO FROM THE MID 40S ON WEDNESDAY NIGHT TO LOW 50S BY THURSDAY
NIGHT.
MODELS CONTINUE TO DIVERGE WITH RESPECT TO THE EVOLVING SPLIT FLOW
PATTERN FORECAST TO FORM OVER THE INTERMOUNTAIN WEST AND
THEREFORE WITH THE NEXT SYSTEM THAT WILL APPROACH THE AREA BY THE
END OF THE WEEK OR EARLY NEXT WEEKEND. DUE TO THE HIGH LEVEL OF
UNCERTAINTY... WILL CONTINUE TO FOLLOW HPC CLOSELY WHICH PREFERS A
GFS/ECMWF BLEND. THIS WOULD RESULT IN INCREASING PRECIPITATION
CHANCES BEGINNING FRIDAY (BUT FOR NOW WILL NOT GO ANY HIGHER THAN
SLIGHT CHANCE DUE TO THE UNCERTAINTY)...AND A RETURN TO NEAR
NORMAL TEMPERATURES FOR THE WEEKEND.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
AS OF 120 AM...
A STRONG SURFACE LOW OVER SOUTHERN KENTUCKY WILL MOVE DUE EAST
INTO WESTERN VIRGINIA BEFORE DIPPING EAST SOUTHEAST TOWARD NORFOLK
DURING THE AFTERNOON. SNOW DEVELOPING AROUND DAWN WILL HAVE A
DIFFICULT TIME REACHING THE GROUND AS MORE THAN FLURRIES AT THE
NORTHERN TAF SITES WITH FAYETTEVILLE DRY. SOME MVFR VISIBILITIES
POSSIBLE UNTIL 10 OR 11 AM. VFR CEILINGS WITH THE LOW... ONLY
GOING MVFR IN THE HEAVIEST BRIEF SNOW SHOWERS. PRECIPITATION
EXITING THE NORTHEAST BY MID AFTERNOON.
STRONG WINDS WILL BEGIN TO REACH THE SURFACE BY MID MORNING IN THE
WEST AND JUST BEFORE NOON TO THE EAST. SUSTAINED NORTHWEST WINDS
OF 15 TO 20 MPH WITH GUSTS TO AT LEAST 35 MPH. WINDS SUBSIDING
FROM WEST TO EAST LATE AFTERNOON TO SUNSET WITH ALL SITES DROPPING
BELOW 10 MPH SHORTLY AFTER DARK.
VFR CONDITIONS INTO EARLY TUESDAY NIGHT... THEN SOME MVFR CEILINGS
POSSIBLE IN THE SOUTH LATE TUESDAY NIGHT INTO WEDNESDAY MORNING. A
PERIOD OF IFR CEILINGS WITH FOG LATE WEDNESDAY NIGHT INTO THURSDAY
MORNING... AND AGAIN LATE THURSDAY NIGHT INTO FRIDAY MORNING...
BUT OTHERWISE VFR.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY FROM 4 AM EARLY THIS MORNING TO NOON
EST TODAY FOR NCZ007>011.
&&
$$
NEAR TERM...SMITH/CBL
SHORT TERM...KRR
LONG TERM...KRR
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
946 AM CST MON MAR 5 2012
.DISCUSSION...
THE MAIN CHALLENGE TODAY WILL BE SNOW BAND THAT IS MOVING INTO
WESTERN MN THIS MORNING. THERE IS A STRONG AREA OF MID LEVEL WARM
AIR ADVECTION AND SATURATION OCCURRING NEAR SNOW BAND. THE OVERALL
MOVEMENT OF THE SNOW SHOULD BE FAST ENOUGH TO PRECLUDE MUCH
SNOW...BUT UP TO AN INCH IS POSSIBLE IN NW MN THIS AFTERNOON. WILL
RAISE POPS THIS AFTERNOON TO ACCOUNT FOR THIS POTENTIAL. IN
ADDITION...WINDS IN THE VALLEY WILL BE FROM THE SOUTH AND GUST TO
25MPH AT TIMES...PERHAPS A BIT HIGHER. THEREFORE EXPECT DRIFTING
SNOW AT LEAST...WITH PLENTY OF FLUFFY SNOW AROUND. IF WINDS
INCREASE A BIT MORE...WILL MONITOR FOR SOME BLOWING SNOW IN OPEN
AREAS THIS AFTERNOON...BUT FOR NOW WON/T MENTION IN THE GRIDS.
&&
.AVIATION...
A BAND OF LIGHT SNOW WILL MOVE INTO NW MN...REDUCING VSBYS AT
TIMES INTO THE IFR RANGE. BREEZY SOUTHERLY WINDS WILL DEVELOP BY
THIS AFTERNOON WITH GUSTS TO 25 KTS POSSIBLE...ESPECIALLY ALONG
THE VALLEY FLOOR WITH SOME BLOWING SNOW A POSSIBILITY.
&&
.PREV DISCUSSION... /ISSUED 340 AM CST MON MAR 5 2012/
SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT
PRIMARY FORECAST CHALLENGE WILL BE TEMPERATURES...WHICH WILL
DEPEND ON A NUMBER OF DIFFERENT FACTORS INCLUDING CLOUDS...SNOW
COVER/TEMPERATURE...WIND DIRECTION/SPEED AND VEGETATION. GFS/NAM/
ECMWF/GEM ARE IN GOOD AGREEMENT AND WILL USE A MODEL BLEND FOR
THIS FORECAST PACKAGE.
EARLY THIS MORNING...DENSE FOG ALONG SURFACE RIDGE AXIS FROM
ELBOW LAKE TO DETROIT LAKES WILL DISSIPATE AND LIFT AS SOUTHERLY
RETURN FLOW INCREASES. GIVEN PATCHY NATURE OF FOG...WILL COVER
HAZARD WITH NOW-CASTS THROUGH THE REST OF THE MORNING.
BIG STORY TODAY WILL BE STRONG WARM AIR ADVECTION FROM THE SURFACE
TO 850 HPA. MID-LEVEL CLOUDS ASSOCIATED WITH THERMAL ADVECTION
WILL MOVE FROM WEST TO EAST THROUGH THE DAY. REGIONAL WSR-88D RADARS
SHOW SOME MODEST ECHOES WITH THESE CLOUDS...BUT NOTHING IS
REACHING THE GROUND. HOWEVER...LATEST HRRR AND 00 UTC ECMWF PAINT
SOME LIGHT QPF ACROSS MUCH OF THE FORECAST AREA THIS MORNING AND
WILL EXPAND 20 POPS FOR LIGHT SNOW ACROSS NORTHWEST MN AND
PORTIONS OF EASTERN ND. ANY ACCUMULATION WILL BE A TENTH OR TWO AT
BEST.
BOUNDARY LAYER WINDS INCREASE TO AROUND 30 KTS BY AFTERNOON...SO
EXPECT BREEZY SOUTHERLY WINDS TO DEVELOP WITH GUSTS TO 25 MPH...
ESPECIALLY ALONG THE VALLEY FLOOR. WIND DIRECTION IS NOT IDEAL FOR
STRONG SURFACE WARMING AND SNOWPACK TEMPERATURES ARE STILL IN THE
20S...SO A LOT OF THERMAL ENERGY SHOULD GO INTO RIPENING THE
SNOWPACK TODAY. AS A RESULT...HIGH TEMPERATURES WILL LIKELY PEAK
NEAR OR SLIGHTLY ABOVE THE FREEZING MARK MOST PLACES. THAT BEING
SAID...THERE COULD BE SOME DRIFTING AND MELTING OF SNOW ON AREA
ROADWAYS...SO SOME SLICK SPOTS ARE LIKELY.
FOR TONIGHT...LIGHT SOUTHERLY WINDS WILL PERSIST...SO TEMPERATURES
WILL HINGE ON CLOUD COVER. EXPECT WIDE VARIABILITY...BUT OVERALL
LOWS SHOULD DROP INTO THE MID TO UPPER 20S.
A STRONG LOW PRESSURE SYSTEM WILL PASS JUST TO OUR NORTH ACROSS
SOUTHERN CANADA ON TUESDAY...KEEPING PRECIPITATION NORTH OF THE
BORDER AND THE FORECAST AREA IN THE WARM SECTOR. 850 HPA TEMPERATURES
SOAR TO +6 TO +8 C AS THE THERMAL RIDGE PASSES OVERHEAD. SNOWPACK
TEMPERATURE WILL BE CLOSER TO FREEZING COMPARED TO MONDAY...SO
HIGHS SHOULD BE ABLE TO CLIMB INTO THE LOW 40S IN SOME AREAS. DID
NOT DEVIATE FAR FROM GUIDANCE ALONG THE VALLEY FLOOR...BUT DID
INCREASE TEMPERATURES A HANDFUL OF DEGREES WEST OF THE VALLEY DUE
TO AN AFTERNOON WESTERLY WIND SHIFT AND ACROSS THE FORESTED AREAS
OF NORTHWEST AND WEST-CENTRAL MN.
A COLD FRONT DROPS SOUTH ACROSS THE REGION TUESDAY NIGHT. MOISTURE
IS LIMITED...BUT DID MAINTAIN AND ADJUST 20 POPS FOR LIGHT RAIN OR
SNOW...CHANGING OVER TO ALL SNOW AFTER MIDNIGHT. LOWS WILL DEPEND
ON TIMING OF FRONTAL PASSAGE...BUT EXPECT A GRADIENT FROM THE LOW
TEENS ALONG THE CANADIAN BORDER TO THE MID 20S ACROSS THE SOUTH.
WEDNESDAY WILL BE COOLER AND MOSTLY DRY WITH HIGH TEMPERATURES IN
THE 20S.
LONG TERM...THURSDAY THROUGH MONDAY
MEDIUM RANGE MODELS START OUT IN FAIRLY DECENT AGREEMENT...WITH THE
NORTHERN BRANCH SHORTWAVE TROUGH MOVING OUT OF THE AREA AND OFF TO
THE EAST ON THURSDAY. THE END OF THE WORK WEEK LOOKS QUIET AND
WARMER AS ALL THE DETERMINISTIC RUNS HAVE 500MB HEIGHTS RISING
OVER THE NORTHERN PLAINS. MODELS CONTINUE TO STRUGGLE WITH HOW TO
HANDLE THE CUT OFF LOW TO OUR SOUTH OVER THE CENTRAL CONUS. THE
GFS HAS THE SYSTEM MOVING OFF INTO MO SUNDAY...WHILE THE ECMWF
TRACKS IT WAY NORTH INTO SD AND BRINGS OUR CWA A LARGE AMOUNT OF
RAIN. THE GEM HAS A MORE SOUTHERN SOLUTION BUT WELL WEST OF THE
GFS. ENSEMBLES ARE ALL OVER THE PLACE...AND GIVEN MODEL
PERFORMANCE LATELY CONFIDENCE IN ANY ONE SOLUTION IS LOW.
HOWEVER...SOME OF THE CANADIAN ENSEMBLE MEMBERS ARE IN AGREEMENT
WITH THE ECMWF AND THERE HAS BEEN SOME CONSISTENCY BETWEEN THE
CURRENT 00Z ECMWF AND THE 12Z RUN. ALLBLEND PUT SOME LOW POPS IN
FOR SATURDAY NIGHT THROUGH SUNDAY NIGHT...AND WILL LEAVE THEM IN
FOR NOW.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
DK
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
340 AM CST MON MAR 5 2012
.SHORT TERM...TODAY THROUGH WEDNESDAY NIGHT
PRIMARY FORECAST CHALLENGE WILL BE TEMPERATURES...WHICH WILL
DEPEND ON A NUMBER OF DIFFERENT FACTORS INCLUDING CLOUDS...SNOW
COVER/TEMPERATURE...WIND DIRECTION/SPEED AND VEGETATION. GFS/NAM/
ECMWF/GEM ARE IN GOOD AGREEMENT AND WILL USE A MODEL BLEND FOR
THIS FORECAST PACKAGE.
EARLY THIS MORNING...DENSE FOG ALONG SURFACE RIDGE AXIS FROM
ELBOW LAKE TO DETROIT LAKES WILL DISSIPATE AND LIFT AS SOUTHERLY
RETURN FLOW INCREASES. GIVEN PATCHY NATURE OF FOG...WILL COVER
HAZARD WITH NOW-CASTS THROUGH THE REST OF THE MORNING.
BIG STORY TODAY WILL BE STRONG WARM AIR ADVECTION FROM THE SURFACE
TO 850 HPA. MID-LEVEL CLOUDS ASSOCIATED WITH THERMAL ADVECTION
WILL MOVE FROM WEST TO EAST THROUGH THE DAY. REGIONAL WSR-88D RADARS
SHOW SOME MODEST ECHOES WITH THESE CLOUDS...BUT NOTHING IS
REACHING THE GROUND. HOWEVER...LATEST HRRR AND 00 UTC ECMWF PAINT
SOME LIGHT QPF ACROSS MUCH OF THE FORECAST AREA THIS MORNING AND
WILL EXPAND 20 POPS FOR LIGHT SNOW ACROSS NORTHWEST MN AND
PORTIONS OF EASTERN ND. ANY ACCUMULATION WILL BE A TENTH OR TWO AT
BEST.
BOUNDARY LAYER WINDS INCREASE TO AROUND 30 KTS BY AFTERNOON...SO
EXPECT BREEZY SOUTHERLY WINDS TO DEVELOP WITH GUSTS TO 25 MPH...
ESPECIALLY ALONG THE VALLEY FLOOR. WIND DIRECTION IS NOT IDEAL FOR
STRONG SURFACE WARMING AND SNOWPACK TEMPERATURES ARE STILL IN THE
20S...SO A LOT OF THERMAL ENERGY SHOULD GO INTO RIPENING THE
SNOWPACK TODAY. AS A RESULT...HIGH TEMPERATURES WILL LIKELY PEAK
NEAR OR SLIGHTLY ABOVE THE FREEZING MARK MOST PLACES. THAT BEING
SAID...THERE COULD BE SOME DRIFTING AND MELTING OF SNOW ON AREA
ROADWAYS...SO SOME SLICK SPOTS ARE LIKELY.
FOR TONIGHT...LIGHT SOUTHERLY WINDS WILL PERSIST...SO TEMPERATURES
WILL HINGE ON CLOUD COVER. EXPECT WIDE VARIABILITY...BUT OVERALL
LOWS SHOULD DROP INTO THE MID TO UPPER 20S.
A STRONG LOW PRESSURE SYSTEM WILL PASS JUST TO OUR NORTH ACROSS
SOUTHERN CANADA ON TUESDAY...KEEPING PRECIPITATION NORTH OF THE
BORDER AND THE FORECAST AREA IN THE WARM SECTOR. 850 HPA TEMPERATURES
SOAR TO +6 TO +8 C AS THE THERMAL RIDGE PASSES OVERHEAD. SNOWPACK
TEMPERATURE WILL BE CLOSER TO FREEZING COMPARED TO MONDAY...SO
HIGHS SHOULD BE ABLE TO CLIMB INTO THE LOW 40S IN SOME AREAS. DID
NOT DEVIATE FAR FROM GUIDANCE ALONG THE VALLEY FLOOR...BUT DID
INCREASE TEMPERATURES A HANDFUL OF DEGREES WEST OF THE VALLEY DUE
TO AN AFTERNOON WESTERLY WIND SHIFT AND ACROSS THE FORESTED AREAS
OF NORTHWEST AND WEST-CENTRAL MN.
A COLD FRONT DROPS SOUTH ACROSS THE REGION TUESDAY NIGHT. MOISTURE
IS LIMITED...BUT DID MAINTAIN AND ADJUST 20 POPS FOR LIGHT RAIN OR
SNOW...CHANGING OVER TO ALL SNOW AFTER MIDNIGHT. LOWS WILL DEPEND
ON TIMING OF FRONTAL PASSAGE...BUT EXPECT A GRADIENT FROM THE LOW
TEENS ALONG THE CANADIAN BORDER TO THE MID 20S ACROSS THE SOUTH.
WEDNESDAY WILL BE COOLER AND MOSTLY DRY WITH HIGH TEMPERATURES IN
THE 20S.
.LONG TERM...THURSDAY THROUGH MONDAY
MEDIUM RANGE MODELS START OUT IN FAIRLY DECENT AGREEMENT...WITH THE
NORTHERN BRANCH SHORTWAVE TROUGH MOVING OUT OF THE AREA AND OFF TO
THE EAST ON THURSDAY. THE END OF THE WORK WEEK LOOKS QUIET AND
WARMER AS ALL THE DETERMINISTIC RUNS HAVE 500MB HEIGHTS RISING
OVER THE NORTHERN PLAINS. MODELS CONTINUE TO STRUGGLE WITH HOW TO
HANDLE THE CUT OFF LOW TO OUR SOUTH OVER THE CENTRAL CONUS. THE
GFS HAS THE SYSTEM MOVING OFF INTO MO SUNDAY...WHILE THE ECMWF
TRACKS IT WAY NORTH INTO SD AND BRINGS OUR CWA A LARGE AMOUNT OF
RAIN. THE GEM HAS A MORE SOUTHERN SOLUTION BUT WELL WEST OF THE
GFS. ENSEMBLES ARE ALL OVER THE PLACE...AND GIVEN MODEL
PERFORMANCE LATELY CONFIDENCE IN ANY ONE SOLUTION IS LOW.
HOWEVER...SOME OF THE CANADIAN ENSEMBLE MEMBERS ARE IN AGREEMENT
WITH THE ECMWF AND THERE HAS BEEN SOME CONSISTENCY BETWEEN THE
CURRENT 00Z ECMWF AND THE 12Z RUN. ALLBLEND PUT SOME LOW POPS IN
FOR SATURDAY NIGHT THROUGH SUNDAY NIGHT...AND WILL LEAVE THEM IN
FOR NOW.
&&
.AVIATION...
IFR STRATUS DECK THIS MORNING ACROSS NORTHWEST MN WILL MOVE EAST
INTO THE ARROWHEAD BY 14 UTC. IN ITS WAKE...MID-HIGH LEVEL CLOUDS
WILL INCREASE FROM THE WEST...BUT DO NOT EXPECT MUCH IN THE WAY OF
PRECIPITATION. BREEZY SOUTHERLY WINDS WILL DEVELOP BY THIS
AFTERNOON WITH GUSTS TO 25 KTS POSSIBLE...ESPECIALLY ALONG THE
VALLEY FLOOR.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...NONE.
&&
$$
ROGERS/JR
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
102 AM EST MON MAR 5 2012
.SYNOPSIS...
AN UPPER LEVEL DISTURBANCE WILL TRACK FROM THE UPPER MIDWEST TO
THE OHIO VALLEY BY DAYBREAK. AHEAD OF THIS TROUGH...SURFACE LOW
PRESSURE WILL SKIRT THE LOWER OHIO VALLEY THIS EVENING AND
OVERNIGHT. HIGH PRESSURE WILL BUILD INTO THE REGION ON MONDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
SNOW HAS FILLED IN ACROSS SOUTHEAST INDIANA AND NORTHERN KENTUCKY
EARLY THIS MORNING. VISIBILITIES ARE GENERALLY RUNNING A MILE OR
GREATER...BUT THEY ARE DROPPING TO ABOUT A HALF MILE AT TIMES IN
SOME OF THE HEAVIER BANDS. THE LATEST COUPLE OF RUC RUNS HAVE
TRENDED QUITE A BIT FARTHER NORTH WITH THE PCPN...CRANKING OUT
UPWARDS OF .15 INCHES OF QPF BY 12Z AS FAR NORTH AS CINCINNATI.
THE LAST FEW RUNS OF THE HRRR ARE ALSO A LITTLE FARTHER NORTH THAN
THE 00Z GFS/NAM RUNS. BASED ON THIS AND RADAR TRENDS...WILL NUDGE
UP ACCUMULATIONS A BIT...BUT STILL KEEP THEM GENERALLY 1-2 INCHES
ALONG AND SOUTH OF THE OHIO RIVER. SINCE IT LOOKS LIKE A PRETTY
QUICK SHOT...WILL HOLD OFF ON EXTENDING THE ADVISORY FARTHER
NORTH AT THIS POINT.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY NIGHT/...
HIGH PRESSURE WILL BUILD INTO THE AREA FROM THE WEST MONDAY INTO
TUESDAY...LEADING TO DRY CONDITIONS. MONDAY WILL REMAIN COOL IN
THE WAKE OF TONIGHTS SNOWFALL AS THE AXIS OF THE HIGH PRESSURE
RIDGE DOES NOT CROSS UNTIL THE LATE DAY. TUESDAY WILL START THE
WARMING TREND WITH READINGS PUSHING INTO THE 50S. LESS CLOUDY
SKIES AND WARM SOUTHERLY FLOW WILL CONTINUE INTO WEDNESDAY AS HIGH
TEMPERATURES WILL CLIMB TOWARDS 60 DEGREES. PM LOWS WILL BE IN THE
20S TONIGHT AND TOMORROW...CLIMB BACK TO THE 30S TUESDAY NIGHT AND
LINGER IN THE UNSEASONABLY MILD 40S WEDNESDAY NIGHT.
&&
.LONG TERM /THURSDAY THROUGH SUNDAY/...
PERIOD BEGINS WITH A COLD FRONT JUST TO THE W OF THE REGION. MODELS
AGREE IN SWINGING THE FRONT THRU THE REGION THURSDAY INTO THURSDAY
NIGHT...BUT DIFFER ON THE TIMING. THE ECMWF/CMC HEMISPHERIC ARE
QUICKER THAN THE GFS. THE ECMWF/CMC ARE PROGRESSIVE WITH THE FRONT
AND PUSH THE PCPN ASSOCIATED WITH IT EWD ON FRIDAY. THE GFS HANGS UP
THE FRONT IN RESPONSE TO AN H5 LOW THAT IS WAS CUTTING OFF IN THE
PLAINS. THIS CUT OFF LOOKS OVER DONE...SO LEANED TOWARDS THE
ECMWF/CMC SOLUTION.
NOT SEEING MUCH IN THE WAY OF SFC BASED INSTABILITY...SO WILL ONLY
CARRY SHRA THU INTO FRI. RIGHT NOW WILL ONLY GO AS HIGH AS 50
POPS...BUT IT WILL PROBABLY NEED TO BE RAISED IF THINGS DONT
CHANGE. HIGH PRESSURE BUILDS IN FRIDAY NIGHT AND SATURDAY. THE COLD
AIR THAT THE ECMWF SPILLS IN COMES IN AFTER THE PCPN HAS ENDS...SO
NO MENTION OF SNOW.
WENT A COUPLE OF DEGREES COOLER THAN HPC TEMPERATURES THROUGH THE
PERIOD...TO BLEND WITH THE COOLER ECMWF.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
A FAST MOVING LOW TO THE SOUTH OF OUR AREA WILL PRODUCE LIGHT TO
MODERATE SNOW OVER SOUTHERN SITES KLUK/KCVG THROUGH 09Z...BECOMING
LIGHT FROM 09Z TIL SUNRISE. LIGHTER SNOW/FLURRIES WILL BE
POSSIBLE ACROSS THE REMAINDER OF OUR TERMINALS THROUGHOUT THE
OVERNIGHT PERIOD. CIGS HAVE BEEN LOWERING OFF TO OUR WEST FOR THE
PAST FEW HOURS AND THIS IS EXPECTED TO SPREAD ACROSS OUR AREA OVER
THE NEXT FEW HOURS. THIS WILL RESULT IN MVFR CIGS ACROSS MOST
TERMINALS BEFORE SUNRISE.
THE LOW WILL MOVE AWAY FROM OUR REGION AFTER SUNRISE
TODAY...RESULTING IN GRADUALLY IMPROVING CIGS AND AN ENDING TO ANY
LINGERING LIGHT SNOW/FLURRIES IN THE AREA. WINDS WILL INCREASE OUT
OF THE NORTHWEST AT THE 10 TO 15 KT RANGE BEHIND THE LOW. BY MID
EARLY AFTERNOON...VFR CONDITIONS SHOULD BEGIN TO PREVAIL FOR THE
REMAINDER OF THE DAY AND INTO MONDAY NIGHT. WINDS WILL BECOME
LIGHT AFTER SUNSET.
OUTLOOK...MVFR CEILINGS AND VISIBILITIES ARE POSSIBLE THURSDAY
INTO FRIDAY.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
KY...WINTER WEATHER ADVISORY UNTIL 4 AM EST EARLY THIS MORNING FOR
KYZ089-090-094>096.
WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR
KYZ097>100.
IN...WINTER WEATHER ADVISORY UNTIL 4 AM EST EARLY THIS MORNING FOR
INZ080.
&&
$$
SYNOPSIS...FRANKS
NEAR TERM...KURZ/JGL
SHORT TERM...FRANKS
LONG TERM...SITES
AVIATION...LATTO
AREA FORECAST DISCUSSION
NWS PORTLAND OR
329 AM PST MON MAR 5 2012
.SYNOPSIS...A STRONG COLD FRONT WILL MOVE DOWN THE WASHINGTON COAST
THIS MORNING AND REACH THE NORTH OREGON COAST BY MID MORNING. THE
FRONT WILL BRING MUCH COLDER AIR INTO THE AREA. WITH LOW SNOW LEVELS
JUST BEHIND THE FRONT. SNOW LEVELS WILL RISE TEMPORALLY AFTER THE
FRONTAL PASSAGE...THEN MUCH COLDER AIR WILL MOVE IN OVERNIGHT. SOME
SHOWERS WILL OCCUR OVERNIGHT IN THE COLD AIR BEFORE NORTHERLY FLOW
ALOFT DRYS THINGS OUT TUESDAY AFTERNOON. WARMER WEATHER WILL RETURN
FOR THE SECOND HALF OF THE WEEK AS A RIDGE OF HIGH PRES BUILDS BACK
OVER THE AREA.
&&
.SHORT TERM...KLGX RADAR IS JUST STARTING TO SHOW THE FRONTAL
BOUNDARY APPROACHING THE N WASHINGTON COAST AT 1030Z. THERE IS A BAND
OF MODERATE PRECIPITATION PROCEEDING THE FRONT ALL THE WAY DOWN TO
ASTORIA. IR SATELLITE IMAGERY SHOWS HIGHER CLOUDS OUT AHEAD OF OF THE
FRONT PROVIDING SOME SEEDING FOR THE MODERATE PRECIPITATION. A LOWER
TOP CLOUD DECK IS SEEN BEHIND THE FRONT WITH THE KLGX RADAR SHOWING
PRECIPITATION CONTINUING BEHIND THE FRONT.
MODELS HAVE BEEN VERY CONSISTENT IN THE FORECAST FOR THIS FRONT. THE
NEW HRRR MODEL SHOWS THE FRONTAL PASSAGE AT ASTORIA AROUND 16Z...WITH
A SHARP WIND SHIFT. PRECIPITATION WILL CONTINUE BEHIND THE SURFACE
FRONT WHICH MEANS THAT SNOW WILL BE FALLING INTO THE REGION OF COLD
ADVECTION BEHIND THE FRONT. THIS SHOULD ALLOW THE SNOW LEVELS TO BE
MUCH LOWER THAN WOULD OTHERWISE BE EXPECTED...ESPECIALLY IF THE
PRECIPITATION IS HEAVY ENOUGH.15 YEARS AGO THE MODELS COULD NOT
HANDLE THIS SITUATION. HOWEVER...TODAYS HIGHER RESOLUTION MODELS DO A
MUCH BETTER JOB WITH THE PHYSICS. THE NAM BUFR SOUNDING AT ASTORIA
SHOWS THIS QUITE NICELY WITH THE TEMPERATURE DROPPING DRAMATICALLY
BETWEEN 17Z AND 18Z AND THE FREEZING LEVEL DROPPING TO ABOUT 1100
FEET...SNOW LEVEL PROBABLY ABOUT 600 FEET...IN THE HEAVIER
PRECIPITATION BEHIND THE FRONT. THIS ONLY LASTS FOR A SHORT TIME
WITH THE TEMPERATURE RISING BY 19Z-20Z AS THE FRONTAL PRECIPITATION
ENDS. IT IS LIKELY THAT THE WILLAPA HILLS AND THE NORTH OREGON
CASCADES WITH GET A BURST OF HEAVY SNOW AND GET A FEW INCHES DURING
THE PERIOD AND AN INCH OR TWO OVERNIGHT IN SHOWERS SO I AM GOING TO
ISSUE A SNOW ADVISORY.
THE LOWER SNOW LEVEL WILL PROGRESS SOUTH ACROSS WESTERN OREGON DURING
THE DAY WITH THE FRONT BUT AS THE FRONT MOVES AWAY FROM THE SOURCE OF
COLD AIR THE EFFECT WILL NOT BE AS DRAMATIC. STILL EXPECT LOWER SNOW
LEVELS AS THE FRONT PASSES...THEN A BRIEF RISE IN SNOW LEVELS DURING
THE AFTERNOON UNTIL THE COLDER AIR MOVES IN OVERNIGHT. WESTERLY FLOW
AND LOWERING SNOW LEVELS WILL RESULT IN SNOW IN THE HIGHER FOOTHILLS
AND IN THE NORTH OREGON AND SOUTH WASHINGTON CASCADES.
MUCH COLDER AIR WILL ADVECT INTO THE REGION DURING THE EVENING AND
OVERNIGHT. BY 10 PM SNOW LEVELS IN THE NORTH WILL BE NEAR THE VALLEY
FLOOR...BUT THE BIG QUESTION IS HOW MUCH MOISTURE AND SHOWERS WILL
THERE BE. THE 06Z NAM AND GFS BOTH SHOW A SHORT WAVE DROPPING DOWN
THE BACK SIDE OF THE TROUGH OVER NORTHWEST OREGON AND SOUTHWEST
WASHINGTON FRONT 06Z TO 12Z. THE MODELS SHOW LIMITED MOISTURE WITH
THIS SHORTWAVE WHICH COULD PRODUCE A DUSTING TO 1 INCH THE LOWLANDS.
MY CONCERN IS THAT THE AIR MASS IS SO COLD THAT IT IS PICKING UP
CONSIDERABLE MOISTURE OVER THE WATER. THIS CAN BE SEEN IN THE IR
IMAGERY WITH A GOOD ORGANIZED BAND OF SHOWERS OFF NORTHERN VANCOUVER
ISLAND EARLY THIS MORNING. THERE IS ABOUT A 40 PERCENT CHANCE THAT
MORE SIGNIFICANT SNOW COULD OCCUR WITH THIS FEATURE...FOR NOW WILL GO
WITH THE 1 INCH AMOUNTS...WATCH HOW THE SHORTWAVE DEVELOPS THIS
EVENING AND BE PREPARED TO MAKE ADJUSTMENTS IF NEEDED.
THE UPPER TROUGH WILL SHIFT EAST QUICKLY TUESDAY AFTERNOON AND
NIGHT. TEMPERATURES WILL GET INTO THE MID 40S IN THE LOWLANDS DURING
THE AFTERNOON TUESDAY SO ANY SNOW THAT DOES FALL SHOULD MELT QUICKLY
DURING THE MORNING. TUESDAY NIGHT WILL SEE SOME BELOW FREEZING
TEMPERATURES IN THE DRYER AIR AND CLEARING SKIES.
MODELS ARE CONSISTENT ON BUILDING THE UPPER RIDGE WITH A GOOD WARMING
TREND WEDNESDAY AND THURSDAY FOR A RETURN TO SPRING WEATHER.
SCHNEIDER
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...THE SECOND
HALF OF THE UPCOMING WEEK IS EXPECTED TO BE DOMINATED BY UPPER LEVEL
RIDGING AND IS LOOKING QUITE NICE. WED SHOULD BE A BIT OF A
TRANSITION DAY AS THE UPPER RIDGE BUILDS IN AND STRENGTHENS BEHIND A
DEPARTING UPPER LEVEL TROUGH. THE MODELS HANG ON TO SOME LOW LEVEL
MOISTURE FROM THE MON/TUE SYSTEM...SO IT LOOKS LIKE THERE WILL BE
SOME LOW CLOUDS AND FOG INTO WED MORNING. LATER WED...THE AIRMASS
SHOULD BEGIN TO DRY OUT AS AN OFFSHORE FLOW PATTERN BEGINS TO DEVELOP
AND HIGH PRESSURE CONTINUES TO STRENGTHEN. THEN THU AND FRI LOOK TO
BE THE WARMEST DAYS OF THE YEAR UP TO THIS POINT. MODELS KEEP
MODERATE OFFSHORE FLOW OVER THE REGION ON THU WITH 850 MB TEMPS IN
THE 8 TO 10 C RANGE. THIS SHOULD MAKE FOR A WARM AND SUNNY DAY. ON
FRI...CURRENT MODEL RUNS SHOW THE FLOW BECOMING MORE SOUTHERLY.
SHOULD BE ANOTHER NICE WARM DAY...BUT WITH TEMPS A BIT COOLER AT THE
COAST DUE TO THE LOSS OF THE OFFSHORE FLOW. THE NICE RUN LOOKS TO END
AS WE HEAD INTO NEXT WEEKEND...WHERE THE MODELS TREND TOWARD
UNSETTLED WEATHER WITH A RETURN TO UPPER LEVEL TROUGHING. JFP
&&
.AVIATION...MVFR STRATUS PRETTY WIDESPREAD THIS MORNING IN
DEEPENING ONSHORE FLOW AHEAD OF AN APPROACHING COLD FRONT. THE
ONSHORE FLOW HAS BEEN A BIT SHALLOWER IN THE SOUTH WILLAMETTE
VALLEY WHICH HAS RESULTED IN AREAS OF IFR FOG INSTEAD OF STRATUS.
HOWEVER...THIS FOG WILL LIKELY LIFT INTO A STRATUS DECK THROUGH
THE MORNING. THE LEADING EDGE OF THE FRONTAL ZONE SHOULD REACH
THE SOUTH WASHINGTON AND FAR NORTH OREGON COAST AROUND 13Z AND
WILL LIKELY DROP CONDITIONS THERE TO IFR BY 15Z IN HEAVIER
RAIN. INLAND AREAS WILL LIKELY STAY LOW-END MVFR FROM 12Z TO 16Z
THEN PREDOMINANT MVFR WITH THE FRONTAL ZONE. HOWEVER...CANNOT RULE
OUT AREAS OF IFR IN HEAVIER RAIN EVEN IN THE INTERIOR. COAST
RANGE MOUNTAINS AND WILLAPA HILLS WILL BE OBSCURED AFTER 15Z MON.
VFR CONDITIONS WILL RETURN IN THE AFTERNOON IN STRONG AND
UNSTABLE ONSHORE FLOW.
KPDX AND APPROACHES...MVFR CONDITIONS WILL CONTINUE THIS MORNING
AHEAD OF A STRONG COLD FRONT. THERE IS A 30 TO 40 PERCENT CHANCE
THAT CEILINGS WILL LOWER TO AROUND FL010 BETWEEN 12Z AND 18Z. RAIN
WILL REACH THE WESTERN APPROACHES AROUND 15Z...WITH CONTINUED MVFR
CONDITIONS. HEAVIEST RAIN WILL BE 18Z TO 21Z. A MUCH COLDER AIR
MASS WILL MOVE IN THIS AFTERNOON...WITH A THREAT OF SNOW SHOWERS
TONIGHT THROUGH TUESDAY MORNING. SNOW ACCUMULATION IS NOT
ANTICIPATED AT THE TERMINAL.
&&
.MARINE...A STRONG COLD FRONT WILL MOVE ACROSS THE WATERS TODAY.
LATEST GUIDANCE BRINGS GALE FORCE WIND GUSTS ACROSS THE NORTHERN
WATERS JUST AHEAD AND WITH THE FRONT. WILL LEAVE THE SOUTHERN
WATERS IN AN ADVISORY FOR WIND AND SEAS FOR NOW. THERE COULD BE
SOME GUSTS TO 35 KT WITH THE FRONT...BUT NOT ENOUGH OR WIDESPREAD
ENOUGH TO HOIST A GALE. POST-FRONTAL NORTHWEST WINDS SHOULD BE
SOLID SMALL CRAFT ADVISORY LEVEL (20-25 KT WITH GUSTS TO 30 KT OR
SO) GIVEN THE IMPRESSIVE COLD ADVECTION BEHIND THE FRONT. THE WIND
WILL DIMINISH TUESDAY EVENING AS HIGH PRESSURE RETURNS TO THE
WATERS AND A LOW DEVELOPS TO THE SOUTH.
SEAS ARE NEAR 10 FT THIS MORNING...CLOSELY MATCHING THE 6-HR FORECAST
FROM THE LATEST GUIDANCE. SEAS WILL BUILD TO 11 TO 13 FT TODAY...
THEN NEAR 15 FT TUESDAY. SEAS WILL FALL BELOW 10 FT ONCE AGAIN BY
LATE
TUESDAY NIGHT OR WEDNESDAY MORNING.
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY FOR SNOW IN THE NORTH OREGON COAST
RANGE...NORTH OREGON CASCADES AND FOOTHILLS TODAY THROUGH
TUESDAY MORNING.
WA...SNOW ADVISORY TODAY THROUGH TUESDAY MORNING FOR THE WILLAPA
HILLS...SOUTH WASHINGTON CASCADES AND FOOTHILLS
PZ...GALE WARNING UNTIL 9 AM PST THIS MORNING FOR COASTAL WATERS FROM
CAPE SHOALWATER WA TO CASCADE HEAD OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR WINDS UNTIL 4 PM PST TUESDAY FOR
COASTAL WATERS FROM CASCADE HEAD TO FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST TUESDAY
FOR COASTAL WATERS FROM CASCADE HEAD TO FLORENCE OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR ROUGH BAR UNTIL 6 AM PST TUESDAY FOR
COLUMBIA RIVER BAR.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
HTTP://WEATHER.GOV/PORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS PORTLAND OR
825 PM PST SUN MAR 4 2012
.SYNOPSIS...A COLD FRONT DROPPING DOWN FROM THE ALEUTIAN ISLANDS LATE
TONIGHT WILL MOVE SE THROUGH THE FORECAST AREA MON. COLDER AIR WILL
FOLLOW MON NIGHT INTO TUE...THEN WARMER WEATHER WILL RETURN FOR THE
SECOND HALF OF THE WEEK AS A RIDGE OF HIGH PRES BUILDS BACK OVER THE
AREA.
&&
.SHORT TERM...SATELLITE IMAGERY SHOWS MOSTLY CLEAR SKIES OVER THE
FORECAST AREA...EXCEPT FOR AN AREA OF FOG IN THE SOUTHERN WILLAMETTE
VALLEY THAT BROKE OUT FOR A COUPLE OF HOURS LATE THIS AFTERNOON AND
HAS ALREADY RE-FORMED. WOULD NOT BE SURPRISED TO SEE SOME FOG AND LOW
CLOUDS RE-DEVELOPING THIS EVENING IN THE REST OF THE VALLEY...BEFORE
CLOUDS AHEAD OF THE APPROACHING FRONT MOVE OVER THE AREA.
MODELS ARE FAIRLY CONSISTENT IN THE TIMING OF THE APPROACHING COLD
FRONT...REACHING THE S WA COAST LATE TONIGHT...THEN PUSHING SE
THROUGH THE REST OF THE FORECAST AREA MON. TROPICAL MOISTURE
ENTRAINING INTO THE SYSTEM FROM THE SSW IS FLOWING OVER THE
FRONT...AND MODELS CONTINUE TO INDICATE MOST OF THE PRECIPITATION IS
POST FRONTAL. A PERIOD OF HEAVIER PRECIPITATION BEHIND THE FRONT WILL
DYNAMICALLY COOL THE AIR MASS...FORCING A QUICK DROP IN SNOW LEVELS.
NAM BUFR SOUNDINGS...IF YOU BUY INTO THEM...SUGGEST A DROP BELOW 1000
FT WITH THE PRECIPITATION MON. WHILE PRECIPITATION MAY BE HEAVY
BEHIND THE FRONT MON...DURATION IS LIMITED...SO IT LOOKS LIKE
MOUNTAINS ARE LIKELY TO WIND UP WITH ADVISORY AMOUNT SNOW.
MODELS ARE IN GOOD AGREEMENT IN SHOWING QUITE A COLD AIR MASS TO
QUICKLY MOVE THROUGH MON NIGHT AND TUE. 1000-500 MB THICKNESS VALUES
ON THE ORDER OF THE 516-519 DM ARE DEPICTED BY 12Z TUE...WITH H8
TEMPS BOTTOMING OUT FROM -8 TO -10 DEG C...WHICH SHOULD BE PLENTY
COLD FOR SNOW TO REACH VALLEY FLOORS. AT ISSUE THOUGH IS HOW
MUCH...IF ANY...PRECIPITATION FALLS MON NIGHT INTO TUE. MODELS DO
DEPICT SOME LOW LEVEL MOISTURE STILL...ESP MON NIGHT WHEN LOW LEVEL
FLOW IS STILL OUT OF THE NW. OVER WATER TRAJECTORIES THOUGH ARE ON
THE SHORT SIDE...BECOMING MORE SO TUE...SO PROBABLY THE BEST CHANCES
FOR SNOW IN THE LOWLANDS WILL COME LATE MON NIGHT WHEN MOISTURE LOOKS
BEST AND A VORT MAX/TROUGH AXIS PUSHES THROUGH.
AS FLOW BECOME MORE NORTHERLY TUE...WILL SEE AIR MASS BEGIN TO DRY
OUT. AS HIGH PRES BUILDS IN TUE NIGHT AND WINDS BECOME LIGHT... WOULD
EXPECT TO SEE CONDITIONS AGAIN FAVORABLE FOR FOG OR LOW CLOUDS.
LIKENS
.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...THE SECOND
HALF OF THE UPCOMING WEEK IS EXPECTED TO BE DOMINATED BY UPPER LEVEL
RIDGING AND IS LOOKING QUITE NICE. WED SHOULD BE A BIT OF A
TRANSITION DAY AS THE UPPER RIDGE BUILDS IN AND STRENGTHENS BEHIND A
DEPARTING UPPER LEVEL TROUGH. THE MODELS HANG ON TO SOME LOW LEVEL
MOISTURE FROM THE MON/TUE SYSTEM...SO IT LOOKS LIKE THERE WILL BE
SOME LOW CLOUDS AND FOG INTO WED MORNING. LATER WED...THE AIRMASS
SHOULD BEGIN TO DRY OUT AS AN OFFSHORE FLOW PATTERN BEGINS TO DEVELOP
AND HIGH PRESSURE CONTINUES TO STRENGTHEN. THEN THU AND FRI LOOK TO
BE THE WARMEST DAYS OF THE YEAR UP TO THIS POINT. MODELS KEEP
MODERATE OFFSHORE FLOW OVER THE REGION ON THU WITH 850 MB TEMPS IN
THE 8 TO 10 C RANGE. THIS SHOULD MAKE FOR A WARM AND SUNNY DAY. ON
FRI...CURRENT MODEL RUNS SHOW THE FLOW BECOMING MORE SOUTHERLY.
SHOULD BE ANOTHER NICE WARM DAY...BUT WITH TEMPS A BIT COOLER AT THE
COAST DUE TO THE LOSS OF THE OFFSHORE FLOW. THE NICE RUN LOOKS TO END
AS WE HEAD INTO NEXT WEEKEND...WHERE THE MODELS TREND TOWARD
UNSETTLED WEATHER WITH A RETURN TO UPPER LEVEL TROUGHING. JFP
&&
.AVIATION...VFR NEARLY EVERYWHERE AT 04Z...EXCEPT FOR MVFR CIGS
ALONG THE S WA COAST AND EXTREME N OREGON COAST AND A SMALL AREA
OF LIFR FOG FROM KCVO TO KEUG. NOT EXPECTING MUCH CHANGE BETWEEN
04Z AND 08Z...BUT AFTER 08Z A LITTLE MORE ONSHORE FLOW AHEAD OF AN
APPROACHING FRONT SHOULD RESULT IN MORE MVFR CIGS ALONG THE COAST
AND COASTAL VALLEYS...AND INCREASED IFR/LIFR FOG FOR THE INLAND
VALLEYS E OF THE COAST RANGE. THE LEADING EDGE OF THE FRONTAL ZONE
SHOULD REACH THE S WA AND FAR N OREGON COAST AROUND 13Z...FOR
PREDOMINANT MVFR CONDITIONS...THEN DROPPING TO IFR BY 15Z IN
HEAVIER PRECIP. INLAND AREAS LIKELY TO STAY IFR/LOW-END MVFR 12Z
TO 16Z THEN PREDOMINANT MVFR WITH THE FRONTAL ZONE. COAST RANGE
MOUNTAINS AND WILLAPA HILLS WILL BE OBSCURED AFTER 15Z MON.
KPDX AND APPROACHES...VFR AT 04Z AND EXPECT IT TO STAY THAT WAY
THROUGH AT LEAST 10Z. SHOULD SEE MVFR CIGS AROUND 10Z WITH A 30 TO
40 PERCENT CHANCE THAT CIGS COULD LOWER TO AROUND FL010 BY 12Z.
PRECIP TO REACH THE WRN APPROACHES AROUND 14Z...WITH MVFR
CONDITIONS THEREAFTER. HEAVIEST PRECIP WILL BE 16Z TO 20Z. MUCH
COLDER AIR MASS MOVES IN MON NIGHT FOR A THREAT OF SNOW SHOWERS.
ANY SNOW THAT DOES OCCUR MON NIGHT WILL BE MINIMAL. WEISHAAR
&&
.MARINE...THE NEXT FRONT EXTENDED FROM 50N 130W TO 44N 136W AT
04Z. LEADING EDGE OF THE FRONT WAS NEARING BUOY 005 WITH GUSTS UP
TO 25 KT. LATEST NAM CAME IN WEAKER WITH THE WIND JUST AHEAD AND
WITH THE FRONT...GENERALLY 25 KT AT THE BOUNDARY LAYER 12Z MON.
THE 00Z RUC WAS SIMILAR. THE 00Z 12KM WRF-GFS SHOWS A CORE OF 25
KT 10M WINDS WITH SOME SPOTS OF 30 KT FROM KTMK N TO THE S WA
COAST. DO NOT SEE ANY MODEL EVIDENCE OF A COASTAL JET DEVELOPING
WITH THIS FRONT. THEREFORE...MADE SOME ADJUSTMENTS TO THE
WARNINGS. EXPANDED THE GALE WARNING TO COVER THE PZZ270
WATERS...WITH A NEW VALID TIME OF 09Z TO 17Z. DECIDED TO GO WITH A
SMALL CRAFT ADVISORY FOR WINDS AND SEAS FOR PZZ255 AND PZZ275.
THERE COULD BE SOME GUSTS TO 35 KT WITH THE FRONT...BUT NOT
ENOUGH OR WIDESPREAD ENOUGH TO GO GALE. POST-FRONTAL NW WINDS
SHOULD BE SOLID SMALL CRAFT ADVISORY LEVEL (20-25 KT WITH GUSTS TO
30 KT OR SO) GIVEN THE IMPRESSIVE COLD ADVECTION BEHIND THE FRONT.
THE WIND WILL DIMINISH TUESDAY EVENING AS HIGH PRESSURE RETURNS TO
THE WATERS AND A LOW DEVELOPS TO THE SOUTH.
SEAS ARE NEAR 10 FT THIS EVENING...CLOSELY MATCHING THE 6-HR
FORECAST FROM THE ENP. SEAS BUILD TO 11 TO 13 FT MON...THEN NEAR
15 FT TUE. SEAS WILL FALL BELOW 10 FT ONCE AGAIN BY LATE TUESDAY
NIGHT OR WEDNESDAY MORNING. WEISHAAR
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...GALE WARNING FROM 1 AM TO 9 AM PST MONDAY FOR COASTAL WATERS
FROM CAPE SHOALWATER WA TO CASCADE HEAD OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR WINDS FROM MIDNIGHT TONIGHT TO 4 PM
PST TUESDAY FOR COASTAL WATERS FROM CASCADE HEAD OR TO FLORENCE
OR OUT 60 NM.
SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST TUESDAY
FOR COASTAL WATERS FROM CASCADE HEAD OR TO FLORENCE OR OUT 60
NM.
SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM MIDNIGHT
TONIGHT TO 6 AM PST TUESDAY.
&&
$$
MORE WEATHER INFORMATION ONLINE AT...
HTTP://WEATHER.GOV/PORTLAND
THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM
THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY
REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1205 AM CST MON MAR 5 2012
.UPDATE...FOR AVIATION.
&&
.AVIATION...06Z TAFS.
COLD FRONT HAS PUSHED EAST OF KBNA. FRONT WL PUSH EAST OF KCSV
AROUND 09Z. EXPECT 5SM -RASN MIX AT KCSV AROUND 09Z WITH A NARROW
WINDOW OF -SN 12-15Z. COLDER H8 AIR EXPECTED LOWER CIGS AT ALL
THREE TERMINALS BY 12Z...TO MAINLY MVFR.
&&
.PREV DISCUSSION... /ISSUED 903 PM CST SUN MAR 4 2012/
DISCUSSION...SFC LOW IS LOCATED NEAR PADUCAH KY AND HAS BEEN
MOVING TOWARD THE SE DURING THE PREVIOUS 4-5 HOURS. IT IS EXPECTED
TO SOON TAKE A MORE EASTERLY COURSE...ALONG THE TN/KY BORDER.
CURRENTLY RAIN IS BEING OBSERVED IN NRN KY ALONG THE OH RIVER WITH
SNOW FURTHER NORTH OVER CENTRAL IL. SCATTERED LIGHT SHOWERS ARE
EXPECTED LATER THIS EVENING. RADAR IS SHOWING SOME REFLECTIVITY
OVER THE AREA. HOWEVER...WITH SFC DEWPOINTS STILL IN THE 20S...IT
WILL TAKE A WHILE FOR OUR ATMOSPHERE TO MOISTEN UP ENOUGH TO GET
RAIN AT THE GROUND.
LOCAL WRF MODEL AND THE HRRR ARE SHOWING PROJECTED REFLECTIVITY
CROSSING MAINLY THE NERN HALF OF THE AREA TONIGHT WITH ONLY MINOR
AMOUNTS OF PRECIPITATION. ANY PRECIP WILL BE LIQUID WITH TEMPS IN
THE BOUNDARY LAYER STILL IN THE 40S. LATER TONIGHT WHEN SFC TEMPS
DROP INTO THE MID 30S...LIGHT SNOW IS POSSIBLE. LITTLE OR NO
ACCUMULATION IS EXPECTED.
WILL LEAVE ZONES ALONE FOR NOW.
PREV DISCUSSION... /ISSUED 542 PM CST SUN MAR 4 2012/
UPDATE...AVIATION.
AVIATION...00Z TAFS.
DISTURBANCE ALOFT W/COLD AIR EXPECTED TO TRIGGER SCT RW- AT
KCKV/KBNA LATE EVE-EARLY AM. AT KCSV...COLDER AIR EXPECTED TO
PRODUCE SOME -SHSN AFT MIDNIGHT. CIGS WL LOWER TO MVFR AFTER
PASSAGE OF SYSTEM WITH COLDER H8 TEMPS. LOW CIGS WL HANG THROUGH
MUCH OF THE MORNING...BUT PCPN WL DEPART.
PREV DISCUSSION... /ISSUED 232 PM CST SUN MAR 4 2012/
DISCUSSION...
CLIPPER SYSTEM CURRENTLY DIVING DOWN THROUGH MIDDLE MISSISSIPPI
VALLEY WITH LOW CENTER OVER KANSAS CITY AT 19Z. SURFACE PRESSURE
GRADIENT IS TIGHT ENOUGH ACROSS THE MID STATE FOR A FEW WIND
GUSTS IN THE 25 TO 30 MPH RANGE. MODELS FORECAST CLIPPER LOW TO
TRACK DOWN THROUGH EXTREME SOUTHERN ILLINOIS THEN INTO WESTERN
KENTUCKY AND ACROSS SOUTHERN KENTUCKY. CLIPPER WILL PULL ENOUGH
MOISTURE NORTHWARD FOR SOME SPRINKLES...LIGHT RAINSHOWERS MAINLY
NORTHERN AREAS OF MID STATE THROUGH EVENING BECOMING MIXED WITH
LIGHT SNOW NORTHEAST MIDDLE AND PLATEAU BECOMING ALL SNOW LATE
NIGHT AND AROUND DAYBREAK ON UPPER END OF PLATEAU. A DUSTING IS
POSSIBLE NORTH OF INTERSTATE 40 COOKEVILLE TO CROSSVILLE. COULD
SEE A HALF INCH FENTRESS AND PICKETT BUT GROUND TEMPS WILL DICTATE.
CLIPPER CLEARS MID STATE QUICKLY AFTER DAYBREAK ON MONDAY WITH
HIGHS GENERALLY IN THE 40S ON MONDAY. UPPER RIDGE BUILDS OVER THE
REGION ON TUESDAY WITH TEMPS BACK UP INTO THE 60S FOR THE REMAINDER
OF THE WEEK. GFS AND EURO CONTINUE TO DIFFER WITH NEXT SYSTEM
COMING OUT OF THE SOUTHWESTERN US ALONG THE SOUTHERN BRANCH OF THE
POLAR JET...BUT BASCIALLY WENT WITH POPS BEGINNING ON THURSDAY AND
CONTINUED RAIN CHANCES INTO WEEKEND. THURSDAY THROUGH WEEKEND
LOOKS BE AN UNSETTLED PERIOD.
&&
.OHX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
04
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
320 AM EST Wed Mar 7 2012
.SYNOPSIS...
08Z water vapor and H4 RUC analysis shows an upper level pattern
consisting of amplified and sharp troughing over the inter-mountain
west, followed downstream by broad longwave ridging over the eastern
half of the CONUS. A weak shortwave impulse is analyzed ejecting
eastward from the main western trough over the southern plains this
morning. Only influence we will see from this impulse is some high
level cirrus streaming overhead to filter the sunshine at times.
Overall the troposphere is still quite dry below this cirrus shown
by the 00Z KTLH sounding.
At the surface, strong 1040mb high pressure centered along the NC
coast continues to ridge back to the west and southwest. Our
position on the southern side of the ridge axis is providing a
steady easterly flow along the NE Gulf coast. The tight gradient is
resulting in a significant nocturnal easterly surge over the coastal
waters this morning, with both buoys gusting to near 30 knots at
times. Similar to Monday night, the breezy conditions are helping to
keep the boundary layer well mixed and our temperatures up. Most
locations are still reporting mid/upper 50s, and do not anticipate
many stations dropping below the upper 40s before sunrise.
&&
.SHORT TERM (Today through Friday)...
Today and Tonight,
Another pleasant and generally dry day upcoming. Weak upper level
ridging will remain in place along the northern Gulf coast, while
surface high pressure is centered well to our NE. On Tuesday we saw
excellent diurnal mixing up to around 800mb, and anticipate similar
mixing conditions today. Mixing up to between 850-800mb will yield
high temperatures generally in the lower to middle 70s. East to
southeast flow should keep temps a few degrees cooler along the
coast from Franklin county westward. Skies will generally end up
partly cloudy as periods of high level cirrus overspread the area
from west to east, and lower level high based cumulus develop in the
fast easterly flow. Hi-res CAM ensembles suggest the development of
a few low topped speed convergence showers across NE Florida/SE
Georgia this afternoon. Not impossible that a brief sprinkle could
make it as far east as the Suwannee River Valley/I-75 Corridor,
however any sprinkles would be of very low impact and will only go
with a silent 10% PoP over our far eastern zones. Due to the strong
easterly flow over the coastal waters, waves refracting back toward
the panhandle coast are expected to produce a high rip current risk
along the panhandle beaches of Walton county. Dry and seasonable
condition tonight with low temps holding in the 50s.
Thursday/Thursday night,
Western U.S upper trough is progged to fracture by Thursday morning
with the southern energy cutting over New Mexico, and the northern
fracture progressing quickly eastward over the Great Lakes/Ohio
Valley. In response to the height falls over the Southern Plains in
advance of the cutoff low, a brief amplification of the ridge over
the Southeastern States will occur. Under the upper ridge we will
experience a dry, pleasant, and even warmer day. 850mb temps rising
to 10-12C and decent diurnal mixing will result in afternoon high
temps rising well into the 70s, with a few 80 degree readings
possible. A weaken gradient during the afternoon hours combined with
the mid/upper 70 temps should result in the development of a feeble
sea-breeze. This flow will again keep temps along the immediate
coast cooler. Upper trough moving into the eastern U.S. Thursday
night/early Friday will begin to break down the upper ridge while
also progressing a weak surface trough into northern AL/GA. At this
time, NWP guidance is in good agreement that any shower activity
associated with this front will remain to our north Thursday night
giving our region a dry and warm overnight period. Low temps in the
mid/upper 50s inland and lower 60s at the coast.
Friday,
Weak upper level impulse will approach the area while the surface
front progresses into our zones. Overall the forcing with this
system is weak which should prevent any organized area of rainfall.
However, with at least some surface focus, and decent instability
progged by the global models(600-1200 J/kg), will expect isolated to
scattered convection during the day. Not expecting a wet forecast,
but those with outdoor activities should plan for the potential of a
passing shower or storm. Outside of the scattered showers, Friday
looks to be a warm and muggy day with temperatures within a few
degrees of 80 away from the immediate coast.
&&
.LONG TERM (Saturday through next Wednesday)...
Overall confidence in this part of the forecast remains below normal
although we are beginning to see at least a modicum of agreement
among a couple of the models. The good news is that the 00Z
operational runs of the GFS and Euro are in better agreement than
last night at this time. Both now show an upper low moving northeast
across the Central Plains at the start of the period with additional
energy hanging back to the southwest. As the plains feature lifts
rapidly northeast toward the Upper Great Lakes by Sunday night, the
southern energy swings east across TX. By Monday, model differences
creep in once again with the GFS bringing a tighter system northeast
up the MS Valley and the new Euro bringing a much weaker system east
across the Gulf states.
At the surface, a front will be positioned just northwest of the
forecast area at the start of the period as an inverted trough
develops over the western Gulf. A strong ridge will build east to
the Mid Atlantic coast on Saturday and force the frontal boundary
through the area and thus returning the forecast area to the
easterly flow regime we are currently experiencing. The ridge will
only slowly drift south into the early to middle part of next week.
However, it does appear to be a deep enough feature to hold any
significant boundaries and upper energy west of the area.
PoPs will be tapered a bit for most periods with a nod toward the
MEX numbers now that the GFS is approximated by the Euro. With few
obvious forcing mechanisms, will hold PoPs mainly in the 20-30
percent range through Tuesday. With the ridging in place for most of
the period, temperature will be above normal for the most part. One
exception will be Saturday when the back door cold frontal passage
will keep max temps in the 60s north of a line from Valdosta to
Dothan. A few of our northeastern zones will not get out of the
lower 60s. Further south, the FL zones will reach the 70s with the
Southeast Big Bend reaching the upper 70s. A moderating trend in
temps will commence across the northern zones on Sunday with
everyone well above normal once again for the Monday through
Wednesday period.
&&
.AVIATION (Through 06Z Thursday)...
VFR conditions are forecast to prevail across the forecast area
through the TAF period. The low level easterly flow regime will
continue on the south side of a surface high that is centered off
the Mid Atlantic coast and ridges southwestward to the eastern Gulf
Coast. Areas of stratus are already moving westward across northeast
FL and southeast GA and some of these clouds are forecast to reach
our terminals later in the morning. In fact, we are forecasting a
VFR ceiling at VLD and ABY shortly after sunrise. This ceiling may
spread west over the remaining terminals by the end of the day. It
should be noted that a few of the hi-res statistical models are
showing higher chances for MVFR ceilings working into the VLD area
this morning. We are still not ready to bite on this and will keep
the forecast VFR until confidence increases that these lower clouds
are actually going to develop. Haven`t seen any yet, even east of
the area.
&&
.MARINE...
A tight gradient on the southern periphery of strong 1040mb high
pressure will continue to result in advisory level winds and seas
over the coastal waters this morning. Winds and seas will begin to
subside this afternoon, especially to the east of of Apalachicola.
Another easterly surge is expected tonight, but only to cautionary
levels. Winds and seas will drop below headline criteria later
Thursday into Friday ahead of an approaching weak front. This front
will wash out over the coastal waters during Saturday with moderate
easterly flow re-developing for the second half of the upcoming
weekend.
&&
.FIRE WEATHER...
An increase in RH today will preclude red flag conditions from being
reached, even across our FL zones. In fact, we see no red flag
events in the offing for the remainder of this week and on into
early next week.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 75 52 78 55 80 / 0 0 0 0 20
Panama City 73 57 74 61 74 / 0 0 0 10 30
Dothan 75 53 78 58 78 / 0 0 0 10 40
Albany 73 52 77 57 78 / 0 0 0 10 30
Valdosta 74 52 78 55 80 / 10 0 0 0 20
Cross City 78 52 80 56 81 / 10 0 10 0 20
Apalachicola 69 59 71 62 71 / 0 0 0 0 20
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
AL...None.
GA...None.
FL...None.
GM...Small Craft Advisory until 5 PM EST this afternoon for Coastal
waters From Ochlockonee River to Apalachicola FL out to 20
NM-Coastal waters from Apalachicola to Destin FL out 20 NM-
Waters from Suwannee River to Apalachicola FL from 20 to 60
NM-Waters from Apalachicola to Destin FL from 20 to 60 NM.
&&
$$
Synopsis/Short Term/Marine...Mroczka
Long Term/Aviation/Fire Wx...Wool
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1015 PM MST TUE MAR 6 2012
.UPDATE...
ISSUED AT 1009 PM MST TUE MAR 6 2012
WIND GUSTS AROUND 45 MPH HAVE DEVELOPED IN THE OAKLEY AND GOVE
AREAS WHERE LOW LEVEL JET MOVING IN FROM THE DDC FORECAST AREA.
THESE WINDS WILL BE BRIEF AND BY 1-2AM CST SHOULD BE EAST OF THE
FORECAST AREA AS COLD FRONT MOVES IN TO THE NORTHWEST PORTION OF
THE AREA. HAVE UPDATED GRIDS TO REFLECT THE HIGHER WINDS.
UPDATE ISSUED AT 926 PM MST TUE MAR 6 2012
TONIGHT-WEDNESDAY...SOUTHERLY WINDS INCREASING ACROSS THE EASTERN
1/3 OF THE AREA WITH GUSTS TO 40 MPH OUT BY HILL CITY. DEWPOINTS
ALSO INCREASING OUT THERE WITH MID 40S BEING REPORTED. HRRR HAS A
GOOD HANDLE ON THE FRONT WHICH WILL MOVE INTO YUMA COUNTY BETWEEN
06-07Z THEN THROUGH THE REST OF THE AREA BY 13Z OR SO WEDNESDAY
MORNING. BEHIND THE FRONT DEWPOINTS WILL INCREASE REPLACING
CURRENT DEWPOINTS GENERALLY IN THE SINGLE DIGITS TO LOW TEENS.
WEDNESDAY MORNING LOW TEMPS IN THE LOW TO MID 30S IN FAR EASTERN
COLORADO TO THE LOW TO MID 40S ACROSS THE FAR EAST (HILL CITY).
HIGH TEMPERATURES WEDNESDAY IN THE LOW TO MID 40S WITH GUSTY N/NE WINDS.
AS FAR AS PRECIPITATION TYPE...SHOULD BE DRY THROUGH 12Z WEDNESDAY
ACROSS THE AREA WITH A SLIM POSSIBILITY OF FREEZING DRIZZLE ACROSS
FAR EASTERN COLORADO (WESTERN 1/2) FROM 12-15Z OR SO. AFTER 15Z
DRY FOR THE REST OF THE DAY.
UPDATE ISSUED AT 629 PM MST TUE MAR 6 2012
HAVE CANCELLED THE RED FLAG WARNING A BIT EARLY. AREAS WITH RH
BELOW 20 PERCENT HAVE WINDS OF 5-15 MPH. AREAS WITH WINDS GUSTING
OVER 25 MPH (HILL CITY AREA) HAVE RH VALUES ABOVE 25 PERCENT.
NO OTHER CHANGES MADE AT PRESENT TIME.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 226 PM MST TUE MAR 6 2012
WINDS WILL DECREASE EARLY THIS EVENING...AND THE LOW PRESSURE CENTER
ASSOCIATED WITH THE LEE TROUGH THIS AFTERNOON WILL SHIFT EASTWARD
OVERNIGHT. A COLD FRONT WILL ENTER THE REGION FROM THE NORTH DURING
THE MID MORNING NEAR 10/11Z. THERE IS A POSSIBILITY FOR PATCHY
FREEZING DRIZZLE DURING THE MID MORNING BEHIND THE FRONT...MAINLY IN
EASTERN COLORADO...BUT MODELS CONTINUE TO SHOW LITTLE IN THE WAY OF
PRECIPITATION DURING THE MORNING HOURS. MOISTURE WILL INCREASE
BEHIND THE FRONT...AND SOUNDINGS SUGGEST ENOUGH LIFT TO FORM LOW
STRATUS BEHIND THE FRONT...THOUGH ISENTROPIC LIFT IS WEAK DURING
THIS PERIOD. FORCING WILL DECREASE BY NOON...PRIMARILY DUE TO THE
MOVEMENT OF THE FRONT THROUGH AND AWAY FROM THE AREA.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 226 PM MST TUE MAR 6 2012
UNCERTAINTY REGARDING THE EVOLUTION/TIMING OF THE FOUR CORNER CLOSED
LOW CONTINUES. GFS CONTINUES TO BE AN EXTREME OUTLIER WITH THE
EVOLUTION OF THE UPPER LOW...AND IS BEING DISCOUNTED CONSIDERING THE
LACK OF ENSEMBLE SUPPORT OR SUPPORT FROM OTHER GUIDANCE. WHILE MOST
GUIDANCE AGREES ON A SINGLE SEMI-STATIONARY CUTOFF LOW CENTERED NEAR
THE FOUR CORNERS WEDNESDAY NIGHT THROUGH SATURDAY THERE CONTINUES TO
BE DIFFERENCES RUN-RUN BETWEEN INDIVIDUAL PIECES OF GUIDANCE ON
EXACT POSITION AND TIMING OF THIS SYSTEM. EVEN WHAT APPEARS TO BE
SLIGHT DIFFERENCES IN THE UPPER LEVEL PATTERN IMPACTS POSITION OF
FAVORABLE LIFT AND MOISTURE RELATION TO THE CWA. THIS IN TURN
AFFECTS DETAILS SUCH AS PRECIP TYPE...AMOUNTS...AND WHERE THE BEST
CHANCE FOR PRECIP WILL ULTIMATELY BE. WITH THIS IN MIND I AM
HESITANT TO MAKE ANY MAJOR CHANGES TO INHERITED POP/WX TYPE FORECAST
THROUGH THESE PERIODS.
IN REGARDS TO POPS...I SPED UP THE ARRIVAL OF PRECIP TUESDAY EVENING
IN THE WEST...WITH SLIGHT CHANCE/CHANCE POPS OVER MOST OF THE CWA
AFTER 03Z. THIS WAS TO ACCOUNT FOR THE POSSIBILITY FOR A FASTER
ARRIVAL OF LIFT/MOISTURE AS INDICATED BY SREF/NAM. BEST CHANCE FOR
PRECIP STILL LOOKS TO BE SOUTH OF INTERSTATE 70 LATE WEDNESDAY NIGHT
THROUGH THURSDAY NIGHT IN CLOSEST PROXIMITY TO STATIONARY
FRONT/BAROCLINIC ZONE.
WAA AND MOISTURE ADVECTION ON THE EASTERN AND NORTHEASTERN FLANK OF
THE UPPER LOW WILL OVERSPREAD THE SOUTHERN AND CENTRAL PLAINS
WEDNESDAY NIGHT AND THURSDAY. SHALLOW COLD AIR SHOULD STILL BE IN
PLACE OVER THE CWA...WHICH WILL LEAD TO THE POSSIBILITY OF
FREEZING RAIN AND SLEET WITH WARM LAYER ALOFT. THE AMOUNT OF MID
LEVEL MOISTURE AND THE AXIS OF WAA ALOFT WILL AFFECT THE CUTOFF
FROM SNOW TO RAIN TO SLEET TO FREEZING RAIN. I KEPT SOME MENTION
OF FREEZING RAIN AND SLEET IN THE WX GRIDS MAINLY IN THE SOUTH AND
EAST PARTS OF THE CWA THROUGH THURSDAY NIGHT JUST TO HIGHLIGHT THE
POSSIBILITY. THERE ARE STILL QUESTIONS REGARDS THE BEHAVIOR OF THE
UPPER LOW...MUCH LESS THESE TYPE OF DETAILS...SO I TRIED NOT TO GO
OVERBOARD IN REGARDS TO ICE/SNOW ACCUMULATIONS. THERE IS TOO MUCH
UNCERTAINTY AT THIS POINT TO PUT OUT WINTER WEATHER HIGHLIGHTS
THIS FORECAST CYCLE.
FRIDAY-SATURDAY...MOST GUIDANCE SHOWS UPPER LOW STARTING TO TO MOVE
OUT OF THE FOUR CORNERS REGION BY FRIDAY NIGHT...WITH GREAT SPREAD
DEVELOPING SATURDAY IN HOW IT EVOLVES AND THE EXACT TRACK THE LOW
CENTER TAKES AS IT TRACKS EAST INTO THE CENTRAL PLAINS. BEST CHANCE
FOR LINGERING PRECIP FRIDAY WILL CONTINUE TO BE IN THE
SOUTH/SOUTHWEST WHERE I ADDED CHANCE POPS. THE AXIS OF BEST
MOISTURE/LIFT SHOULD BE PREDOMINANTLY EAST OF THE CWA BY SATURDAY.
ECMWF/GEM SOLUTIONS ARE A LITTLE SLOWER IN BRINGING AN END TO
PRECIP...SO I LEFT SLIGHT CHANCE POPS IN PLACE SATURDAY AND SATURDAY
NIGHT ACROSS THE EXTREME EASTERN PARTS OF THE CWA.
SUNDAY-TUESDAY...GUIDANCE STARTS TO COME INTO BETTER AGREEMENT ON
PATTERN ACROSS THE PLAINS BY SUNDAY. SHORTWAVE RIDGING SHOULD
QUICKLY FOLLOW THE EXIT OF THE UPPER LOW...WITH W/SW FLOW BUILDING
BACK OVER THE PLAINS. THIS PATTERN WILL FAVOR DRY CONDITIONS AND
WARMING TEMPERATURES. FORECAST REFLECTS THESE TRENDS WITH
TEMPERATURES NEAR 60F ON SUNDAY...LOW/MID 60S ON MONDAY...AND
MID/UPPER 60S ON TUESDAY.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY EVENING)
ISSUED AT 1015 PM MST TUE MAR 6 2012
GUSTY S/SW WINDS TO CONTINUE THROUGH EARLY WEDNESDAY MORNING
BEFORE A COLD FRONT MOVES IN BRINGING WITH IT GUSTY N/NE WINDS
WHICH WILL CONTINUE THROUGH THE DAY. SUB-VFR CIGS EXPECTED AT KGLD
AROUND 11Z AND CONTINUING THROUGH 19Z OR SO WHILE AT KMCK SUB-VFR
CIGS EXPECTED FROM 12Z-18Z. BY MID TO LATE AFTERNOON VFR
CONDITIONS EXPECTED AT BOTH TERMINALS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
KS...NONE.
NE...NONE.
&&
$$
UPDATE...007
SHORT TERM...CJS
LONG TERM....DR
AVIATION...007
AREA FORECAST DISCUSSION
NWS GOODLAND KS
931 PM MST TUE MAR 6 2012
.UPDATE...
ISSUED AT 926 PM MST TUE MAR 6 2012
TONIGHT-WEDNESDAY...SOUTHERLY WINDS INCREASING ACROSS THE EASTERN
1/3 OF THE AREA WITH GUSTS TO 40 MPH OUT BY HILL CITY. DEWPOINTS
ALSO INCREASING OUT THERE WITH MID 40S BEING REPORTED. HRRR HAS A
GOOD HANDLE ON THE FRONT WHICH WILL MOVE INTO YUMA COUNTY BETWEEN
06-07Z THEN THROUGH THE REST OF THE AREA BY 13Z OR SO WEDNESDAY
MORNING. BEHIND THE FRONT DEWPOINTS WILL INCREASE REPLACING
CURRENT DEWPOINTS GENERALLY IN THE SINGLE DIGITS TO LOW TEENS.
WEDNESDAY MORNING LOW TEMPS IN THE LOW TO MID 30S IN FAR EASTERN
COLORADO TO THE LOW TO MID 40S ACROSS THE FAR EAST (HILL CITY).
HIGH TEMPERATURES WEDNESDAY IN THE LOW TO MID 40S WITH GUSTY N/NE WINDS.
AS FAR AS PRECIPITATION TYPE...SHOULD BE DRY THROUGH 12Z WEDNESDAY
ACROSS THE AREA WITH A SLIM POSSIBILITY OF FREEZING DRIZZLE ACROSS
FAR EASTERN COLORADO (WESTERN 1/2) FROM 12-15Z OR SO. AFTER 15Z
DRY FOR THE REST OF THE DAY.
UPDATE ISSUED AT 629 PM MST TUE MAR 6 2012
HAVE CANCELLED THE RED FLAG WARNING A BIT EARLY. AREAS WITH RH
BELOW 20 PERCENT HAVE WINDS OF 5-15 MPH. AREAS WITH WINDS GUSTING
OVER 25 MPH (HILL CITY AREA) HAVE RH VALUES ABOVE 25 PERCENT.
NO OTHER CHANGES MADE AT PRESENT TIME.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 226 PM MST TUE MAR 6 2012
WINDS WILL DECREASE EARLY THIS EVENING...AND THE LOW PRESSURE CENTER
ASSOCIATED WITH THE LEE TROUGH THIS AFTERNOON WILL SHIFT EASTWARD
OVERNIGHT. A COLD FRONT WILL ENTER THE REGION FROM THE NORTH DURING
THE MID MORNING NEAR 10/11Z. THERE IS A POSSIBILITY FOR PATCHY
FREEZING DRIZZLE DURING THE MID MORNING BEHIND THE FRONT...MAINLY IN
EASTERN COLORADO...BUT MODELS CONTINUE TO SHOW LITTLE IN THE WAY OF
PRECIPITATION DURING THE MORNING HOURS. MOISTURE WILL INCREASE
BEHIND THE FRONT...AND SOUNDINGS SUGGEST ENOUGH LIFT TO FORM LOW
STRATUS BEHIND THE FRONT...THOUGH ISENTROPIC LIFT IS WEAK DURING
THIS PERIOD. FORCING WILL DECREASE BY NOON...PRIMARILY DUE TO THE
MOVEMENT OF THE FRONT THROUGH AND AWAY FROM THE AREA.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 226 PM MST TUE MAR 6 2012
UNCERTAINTY REGARDING THE EVOLUTION/TIMING OF THE FOUR CORNER CLOSED
LOW CONTINUES. GFS CONTINUES TO BE AN EXTREME OUTLIER WITH THE
EVOLUTION OF THE UPPER LOW...AND IS BEING DISCOUNTED CONSIDERING THE
LACK OF ENSEMBLE SUPPORT OR SUPPORT FROM OTHER GUIDANCE. WHILE MOST
GUIDANCE AGREES ON A SINGLE SEMI-STATIONARY CUTOFF LOW CENTERED NEAR
THE FOUR CORNERS WEDNESDAY NIGHT THROUGH SATURDAY THERE CONTINUES TO
BE DIFFERENCES RUN-RUN BETWEEN INDIVIDUAL PIECES OF GUIDANCE ON
EXACT POSITION AND TIMING OF THIS SYSTEM. EVEN WHAT APPEARS TO BE
SLIGHT DIFFERENCES IN THE UPPER LEVEL PATTERN IMPACTS POSITION OF
FAVORABLE LIFT AND MOISTURE RELATION TO THE CWA. THIS IN TURN
AFFECTS DETAILS SUCH AS PRECIP TYPE...AMOUNTS...AND WHERE THE BEST
CHANCE FOR PRECIP WILL ULTIMATELY BE. WITH THIS IN MIND I AM
HESITANT TO MAKE ANY MAJOR CHANGES TO INHERITED POP/WX TYPE FORECAST
THROUGH THESE PERIODS.
IN REGARDS TO POPS...I SPED UP THE ARRIVAL OF PRECIP TUESDAY EVENING
IN THE WEST...WITH SLIGHT CHANCE/CHANCE POPS OVER MOST OF THE CWA
AFTER 03Z. THIS WAS TO ACCOUNT FOR THE POSSIBILITY FOR A FASTER
ARRIVAL OF LIFT/MOISTURE AS INDICATED BY SREF/NAM. BEST CHANCE FOR
PRECIP STILL LOOKS TO BE SOUTH OF INTERSTATE 70 LATE WEDNESDAY NIGHT
THROUGH THURSDAY NIGHT IN CLOSEST PROXIMITY TO STATIONARY
FRONT/BAROCLINIC ZONE.
WAA AND MOISTURE ADVECTION ON THE EASTERN AND NORTHEASTERN FLANK OF
THE UPPER LOW WILL OVERSPREAD THE SOUTHERN AND CENTRAL PLAINS
WEDNESDAY NIGHT AND THURSDAY. SHALLOW COLD AIR SHOULD STILL BE IN
PLACE OVER THE CWA...WHICH WILL LEAD TO THE POSSIBILITY OF
FREEZING RAIN AND SLEET WITH WARM LAYER ALOFT. THE AMOUNT OF MID
LEVEL MOISTURE AND THE AXIS OF WAA ALOFT WILL AFFECT THE CUTOFF
FROM SNOW TO RAIN TO SLEET TO FREEZING RAIN. I KEPT SOME MENTION
OF FREEZING RAIN AND SLEET IN THE WX GRIDS MAINLY IN THE SOUTH AND
EAST PARTS OF THE CWA THROUGH THURSDAY NIGHT JUST TO HIGHLIGHT THE
POSSIBILITY. THERE ARE STILL QUESTIONS REGARDS THE BEHAVIOR OF THE
UPPER LOW...MUCH LESS THESE TYPE OF DETAILS...SO I TRIED NOT TO GO
OVERBOARD IN REGARDS TO ICE/SNOW ACCUMULATIONS. THERE IS TOO MUCH
UNCERTAINTY AT THIS POINT TO PUT OUT WINTER WEATHER HIGHLIGHTS
THIS FORECAST CYCLE.
FRIDAY-SATURDAY...MOST GUIDANCE SHOWS UPPER LOW STARTING TO TO MOVE
OUT OF THE FOUR CORNERS REGION BY FRIDAY NIGHT...WITH GREAT SPREAD
DEVELOPING SATURDAY IN HOW IT EVOLVES AND THE EXACT TRACK THE LOW
CENTER TAKES AS IT TRACKS EAST INTO THE CENTRAL PLAINS. BEST CHANCE
FOR LINGERING PRECIP FRIDAY WILL CONTINUE TO BE IN THE
SOUTH/SOUTHWEST WHERE I ADDED CHANCE POPS. THE AXIS OF BEST
MOISTURE/LIFT SHOULD BE PREDOMINANTLY EAST OF THE CWA BY SATURDAY.
ECMWF/GEM SOLUTIONS ARE A LITTLE SLOWER IN BRINGING AN END TO
PRECIP...SO I LEFT SLIGHT CHANCE POPS IN PLACE SATURDAY AND SATURDAY
NIGHT ACROSS THE EXTREME EASTERN PARTS OF THE CWA.
SUNDAY-TUESDAY...GUIDANCE STARTS TO COME INTO BETTER AGREEMENT ON
PATTERN ACROSS THE PLAINS BY SUNDAY. SHORTWAVE RIDGING SHOULD
QUICKLY FOLLOW THE EXIT OF THE UPPER LOW...WITH W/SW FLOW BUILDING
BACK OVER THE PLAINS. THIS PATTERN WILL FAVOR DRY CONDITIONS AND
WARMING TEMPERATURES. FORECAST REFLECTS THESE TRENDS WITH
TEMPERATURES NEAR 60F ON SUNDAY...LOW/MID 60S ON MONDAY...AND
MID/UPPER 60S ON TUESDAY.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING)
ISSUED AT 410 PM MST TUE MAR 6 2012
GUSTY WINDS WILL SUBSIDE EARLY THIS EVENING WITH THE POTENTIAL
FOR SUB-VFR CONDITIONS BY MID MORNING WEDNESDAY AS A COLD FRONT
MOVES THROUGH THE TERMINALS NEAR 10/11Z. BEHIND THE FRONT WINDS
WILL SHIFT TO THE NORTH-NORTHEAST AROUND 20G30KTS. MODEL
SOUNDINGS ALSO INDICATE THAT STRATUS IS MORE LIKELY THAN FOG...AND
THE NAM IS THE ONLY MODEL CURRENTLY INDICATING PRECIP BEHIND THE
FRONT. WHILE THE NAM SOUNDINGS SUPPORT FREEZING DRIZZLE...BOTH THE
NAM AND GFS SUPPORT LOW STRATUS...AND THE EC ALSO KEEPS PRECIP
FROM THE TERMINALS. HAVE INCLUDED MVFR CEILINGS AT BOTH
TERMINALS...WITH THE CEILING RISING BEHIND THE FRONT LATE IN THE
PERIOD.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
KS...NONE.
NE...NONE.
&&
$$
UPDATE...007
SHORT TERM...CJS
LONG TERM....DR
AVIATION...CJS/007
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1208 AM EST WED MAR 7 2012
.UPDATE...
ISSUED AT 810 PM EST TUE MAR 6 2012
UPDATED TO LOWER MIN TEMPS A BIT OVER THE CENTRAL AND E GIVEN RECENT
TRENDS WITH FAIRLY LGT WINDS/MOCLR SKIES. EXPECT TEMPS TO STEADY OUT
AND THEN RISE A BIT IN THESE AREAS WITH ARRIVAL OF THICKER CLDS/MORE
LLVL MSTR LATER WITH STEADY SSW WIND. ADDED PATCHY FOG EARLIER OVER
THE E GIVEN SHARPER DIURNAL TEMP FALL THERE THIS EVNG.
&&
.SYNOPSIS...
ISSUED AT 405 PM EST TUE MAR 6 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A TROF MOVING INTO THE
ROCKIES WITH A BROAD DOWNSTREAM RIDGE EXPANDING FROM THE CNTRL TO
ERN CONUS. MAIN PORTION OF THIS TROF WILL SHIFT ACROSS THE NRN
CONUS/GREAT LAKES AND NEW ENGLAND OVER THE NEXT SEVERAL DAYS WHILE
ENERGY IN THE SRN PORTION OF THE TROF BREAKS OUT AND CLOSES OFF OVER
THE SW STATES. TROF WILL BRING A PERIOD OF PCPN WED THRU THU.
EVENTUALLY...THE SW LOW WILL EJECT OUT TO THE NE OVER THE
WEEKEND/EARLY NEXT WEEK. WHAT AFFECTS THE LOW WILL HAVE OVER THE
UPPER LAKES REMAINS TO BE SEEN.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY)
ISSUED AT 405 PM EST TUE MAR 6 2012
IN THE SHORT TERM...CONCERNS REVOLVE AROUND TEMP TRENDS...FOG
DEVELOPMENT AND THEN PCPN WED ASSOCIATED WITH COLD FRONT/TROF MOVING
INTO THE UPPER LAKES.
DWPTS ARE RISING INTO THE MID 30S TO LWR 40S AS FAR NE SE MN/SW WI
THIS AFTN WITH TRAJECTORIES BRINGING THAT MOISTURE INTO UPPER MI
DURING THE NIGHT AND WED MORNING. WITH THE LOW-LEVEL MOISTURE
ADVECTION OVER THE SNOW COVER...STRATUS/FOG SHOULD EVENTUALLY
DEVELOP TONIGHT. DENSE FOG MAY DEVELOP...ESPECIALLY OVER UPSLOPE
HIGHER TERRAIN LATE TONIGHT INTO WED. IF THERE WAS SOME ADDITIONAL
MOISTURE FROM RAIN/DRIZZLE...WOULD GO WITH MORE OF A DENSE FOG
WORDING. FOR NOW...GOING FCST OF AN INCREASE IN LOWER CLOUDS AND FOG
DEVELOPMENT...MAINLY LATER TONIGHT...LOOKS ON TRACK. TEMPS SHOULDN`T
FALL MUCH IF AT ALL UNDER MOISTURE ADVECTION AND FAIRLY TIGHT PRES
GRADIENT/STIRRING WINDS. MINS SHOULD BE IN THE MID 30S TO LWR 40S...
WARMEST IN THE DOWNSLOPE AREAS NEAR LAKE SUPERIOR.
COLD FRONT IS STILL ON TRACK TO MOVE THRU THE AREA LATER WED
AFTN/EVENING AS SFC LOW MOVES ACROSS NORTHERN PORTIONS OF ONTARIO.
EVEN WITH CLOUDS/FOG (POSSIBLY DENSE) AHEAD OF THE FRONT...WARM
START TO THE DAY SHOULD ALLOW TEMPS TO RISE WELL INTO THE 40S AHEAD
OF THE FRONT WED. FCST SOUNDINGS FROM NAM/GFS INDICATE RAIN WILL BE
PTYPE. EXCEPTION WILL BE THE FAR W LATE IN THE DAY. SOUNDINGS THERE
INITIALLY SHOW COOLING WORKING IN BLO 850MB...THEN SHOW ALL OF THE
PROFILE NEAR OR BLO 0C LATE AFTN...RESULTING IN CHANGE TO SNOW...
WITH SLEET POSSIBLE AT LEAST BRIEFLY AS WELL. WITH SLOWER COOLING
NOTED BY GEM/UKMET...OPTED TO SLOW CHANGEOVER BY A FEW HRS. NOT
EXPECTING ANY SNOW/SLEET ACCUMULATION WED WITH TEMPS WELL INTO THE
30S THRU LATE AFTN OVER THE W. OTHERWISE...WITH ASSISTANCE OF RIGHT
ENTRANCE OF UPPER JET...EXPECT AN AREA OF -RA TO DEVELOP
(LIKELY/CATEGORICAL POPS)...MOSTLY ALONG/JUST BEHIND COLD FRONT.
.LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY)
ISSUED AT 405 PM EST TUE MAR 6 2012
COLD FRONT WILL BE STRETCHED FROM NE TO SW ACROSS THE CNTRL/ERN CWA
AT THE START OF THE PERIOD...WHILE THE UPPER TROUGH IS STARTING TO
PUSH INTO THE UPPER GREAT LKS. THIS FRONT WILL CONTINUE TO SLIDE SE
INTO NRN LOWER MI DURING THE EARLY OVERNIGHT HRS. PCPN DEVELOPING
ALONG THE FRONT TOMORROW AFTN WILL LARGELY BE FOCUSED OVER THE ERN
CWA AT THE START OF THE PERIOD. THIS SHOULD BE FALLING AS RAIN...DUE
TO THE ABUNDANT WAA FROM H925-800 LEADING TO TEMPS AT OR ABOVE 3C.
FARTHER W IN CNTRL AND WRN UPPER MI...LLVL COLD AIR SURGING IN
BEHIND THE FRONT WILL BRING IN A COLD LAYER FOR THE PCPN TO FALL
INTO. THE MAIN QUESTION IS HOW QUICKLY THAT COLD AIR WILL SURGE IN
BEHIND THE PCPN SHIFTING TO THE SE. MAY NOT BE ENOUGH COLD AIR TO
ALLOW SLEET TO OCCUR...BUT DID MENTION A SLIGHT CHANCE OF IT ON THE
BACK SIDE OF THE MAIN PCPN. IN ADDITION...SOME CONCERNS ON ICE
CRYSTAL PRESENCE IN THE CLOUDS ON THE BACK EDGE OF THE PCPN. EVEN AS
TEMPS START TO COOL BEHIND THE FRONT...THEY REALLY DON/T FALL MUCH
BELOW -5C UNTIL THE BULK OF THE PCPN HAS MOVED TO THE EAST. THINKING
IT WILL LARGELY BE A RAIN...THEN A QUICK PERIOD OF SLEET AND EITHER
END OR BE A SLIGHT DZ/FLURRIES.
THINK BEST CHANCES FOR SNOW WILL BE OVER THE W IN THE EVENING...AS
THE COLD AIR ALLOWS FOR LK ENHANCEMENT WITH H900-875 TEMPS FALLING
TO -8C. CLOUD DEPTH SHOULD BE LIMITED WITH THE INVERSION AROUND H850
OR 3KFT. THUS...WILL MAINLY BE FLURRIES OR LIGHT SNOW SHOWERS AND
LINGERED CHANCES/SLIGHTS OVER THE NW FAVORED LOCATIONS IN THE W
THROUGH THE EARLY OVERNIGHT HRS. DRY LLVL AIR WILL THEN QUICKLY WORK
IN OVERNIGHT...SO HAVE DIMINISHED THE LINGERING POPS QUICKLY FROM W
TO E NEAR LK SUPERIOR.
THERE IS SOME POTENTIAL FOR CLEARING OVER THE INTERIOR W LATE IN THE
NIGHT...WHICH COULD ALLOW TEMPS TO FALL BELOW GUIDANCE WITH PWAT
VALUES AROUND 55 PERCENT OF NORMAL. WINDS WILL BE DIMINISHING WITH
THE APPROACHING SFC RIDGE...BUT MAY NOT ARRIVE EARLY ENOUGH TO
MAXIMIZE THE RADIATIONAL COOLING. WILL HIGHLIGHT THE COLDEST VALUES
NEAR WATERSMEET WITH LOWS IN THE UPPER TEENS.
UPPER TROUGH WILL BE MOVING OVER THE UPPER GREAT LAKES THROUGH
THE DAY ON THURS...ALLOWING SFC LOW TO DEVELOP OVER SRN ONTARIO
THURS AFTN AND INTENSIFY AS IT MOVES SE ON THURS NIGHT. DRY AIR
ABOVE H850 BEHIND THE FRONT WILL BE PUSHING FROM NW TO SE ACROSS THE
AREA THURS MORN AHEAD OF SECONDARY TROUGH BRINGING DEEPER MOISTURE
AND COLDER AIR. THINK THIS WILL LEAD TO A PERIOD OF PARTLY CLOUDY
TO MOSTLY SUNNY SKY OVER MUCH OF THE CWA IN THE MORNING. THEN...AS
THE TROUGH MOVES INTO THE AREA AND BRINGS DEEPER MOISTURE AND
H850-700 Q-VECTOR CONV...HAVE INCREASED CLOUDS AND BRING
SLIGHT/CHANCES OF SNOW BACK IN THE AFTN NEAR LK SUPERIOR.
UPPER TROUGH WILL START TO PUSH E ON THURS NIGHT AND CONTINUE E ON
FRI...AS RIDGING STARTS TO MOVE OVER THE AREA AND SFC HIGH PUSHES
INTO THE WRN GREAT LKS. WITH SECONDARY COLD FRONT DROPPING SE
ACROSS LK SUPERIOR...EXPECT ADDITIONAL LLVL MOISTURE AND FALLING
H850 TEMPS TOWARDS -13C TO LEAD TO INCREASING LAKE
EFFECT/ENHANCEMENT FOR AREAS NEAR LK SUPERIOR. WITH THE STRONG NW
AND THEN NNW WINDS...EXPECT CLOUD COVER TO SPREAD ACROSS MUCH OF
THE AREA THURS NIGHT AND CONTINUE INTO FRI MORNING. WITH THE COLD
AIR SPILLING IN...EXPECT GUSTY WINDS AS H925 WINDS TO 35KTS OVER THE
NE HALF OF THE CWA TO MIX TO THE SFC AND PRODUCE 25-35KT GUSTS NEAR
LK SUPERIOR E OF MARQUETTE. OVERALL...DON/T EXPECT TOO MUCH SNOW
ACCUM AS THE PERIOD OF FAVORABLE CONDITIONS IT FAIRLY LIMITED ON
THURS NIGHT...BEFORE DRIER AIR ARRIVES AND LOWERING INVERSION
HEADING THROUGH THE DAY ON FRI. IN ADDITION...WITH THE INCREASING
H850 WAA ON FRI AFTN OVER THE WRN LK WILL ALSO AID TO END THE
LINGERING LES FROM W TO E THROUGH THE DAY FRI. ALL IN
ALL...THURS AND FRI LOOK TO BE A PERIOD OF NORMAL TO BELOW
NORMAL TEMPS ACROSS THE AREA AHEAD OF THE POTENTIAL WARM-UP FOR
THE WEEKEND INTO NEXT WEEK.
DAYS 4 THROUGH 7 /FRI NIGHT THROUGH TUESDAY/...
UPPER LOW SPINNING OVER THE FOUR CORNERS REGION ON FRI NIGHT WILL
BEGIN TO GET CAUGHT UP WITH THE FLOW AND DRIFT NNE.
MEANWHILE...NEARLY ZONAL FLOW NRN STREAM LOOKS TO BE SETUP OVER SRN
CANADA...KEEPING THE COLD AIR WELL N OF THE UPPER GREAT LKS.
12Z RUNS CONTINUE THE DIFFERENCES WITH THE TRACK OF THE
UPPER LOW. HPC PREFERS A CONSENSUS SOLN NOT INCLUDING THE
GFS...WHICH TRACKS THE LOW MUCH FASTER AND FARTHER SE. 12Z RUN IS
THE SAME AND REMAINS VERY CONSISTENT OVER THE LAST SEVERAL
RUNS...WHICH COULD LEAD SOME CREDIT TO THE THAT SOLN. ENS MEAN ON
ECMWF/GEM IS A LITTLE SLOWER THAN THE DETERMINISTIC RUN...BUT
FOLLOWS A SIMILAR TRACK. OVERALL CONSENSUS PULLS THE UPPER LOW
THROUGH THE GREAT LKS REGION SUN INTO MON. WILL CONTINUE TO MENTION
CHANCE POPS ACROSS THE AREA...WHICH SHOULD FALL AS RAIN DUE TO THE
WARM AIR ALREADY IN PLACE.
EXTENDED MODELS CONTINUE TO SHOW THE POTENTIAL FOR A BIG WARM UP
BEHIND THE UPPER LOW THAT MOVES THROUGH THE GREAT LKS. AMPLIFYING
AND NEARLY STATIONARY TROUGH OFF THE W COAST OF THE CONUS WILL LEAD
TO AMPLIFYING RIDGE OVER THE CANADIAN PRAIRIES. THIS WILL ALLOW SFC
HIGH TO BE STATIONED OVER THE ERN CONUS AND WITH THE MAIN LOWS
TRACKING WELL TO THE N THROUGH CANADA...EXPECT SRLY FLOW TO BE SETUP
OVER THE CWA. CONSENSUS OF THE MODELS GIVES VALUES IN THE 40S AND
NEAR 50 ALONG THE WI BORDER FOR HIGHS ON TUES. THIS IS USUALLY UNDER
DONE IN WELL ABOVE NORMAL SITUATIONS AND THE ECMWF /WHICH ALMOST
ALWAYS VERIFIES THE BEST IN THESE ABOVE NORMAL SITUATIONS/ HAS
VALUES ABOUT 7-10 DEGREES WARMER THAN THE CONSENSUS. THE TEMPS LOOK
TO GET EVEN WARMER HEADING INTO WED/THURS. ECMWF HAS TEMPS FOR
WED/THURS OF NEXT WEEK OVER THE W HALF IN THE 60S WITH COOLER TEMPS
NEAR LK MI WITH THE SSW FLOW. ECMWF EVEN ATTEMPTS TO TRY AN PUSH A
FEW 70S ALONG THE WI BORDER.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT)
ISSUED AT 1208 AM EST WED MAR 7 2012
SINCE THE RH OF THE INCOMING AIRMASS REMAINS FAIRLY LO DUE TO THE
ANOMALOUS WARMTH...DELAYED THE ARRIVAL OF LO CLDS/FOG AT ALL 3
SITES. SAW STILL LOOKS TO HAVE THE BEST SHOT AT SEEING AT LEAST AN
MVFR CIG/VSBY BY 12Z WITH MORE OF AN UPSLOPE WIND COMPONENT...BUT
DOWNSLOPE NATURE OF S WIND AT IWD/CMX ARGUES AGAINST GOING LOWER
THAN VFR THRU SUNRISE. SINCE THE PRES GRADIENT HAS WEAKENED OVER
CMX...REMOVED LLWS FROM THE TAF FOR THAT LOCATION. STILL EXPECTING
SOME LO CLDS TO ARRIVE AHEAD OF INCOMING COLD FNT BY THIS AFTN WITH
HIER DEWPTS SURGING INTO THE UPR LKS...BUT TRENDED BACK A BIT FM THE
PREVIOUS FCST OF IFR EXCEPT AT SAW GIVEN MORE FAVORABLE UPSLOPE S
WIND. BEST SHOT AT IFR/PERHAPS LIFR WL BE RIGHT BEHIND COLD FROPA AT
CMX WITH UPSLOPE WNW WIND...BUT PCPN INTENSITY LOOKS A BIT LESS
IMPRESSIVE WITH BEST FORCING PROGGED TO PASS TO THE NW. THE ARRIVAL
OF COLDER AIR IN THE WAKE OF THE FROPA WL CHANGE THE PCPN TO SHSN...
BUT CONDITIONS SHOULD IMPROVE TO MVFR GIVEN MODERATE CHILL OF THE
INCOMING AIRMASS THAT WL LIMIT LES INTENSITY.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 405 PM EST TUE MAR 6 2012
SOUTHERLY WINDS OF 20-30KT OVER ERN LAKE SUPERIOR (LIGHTER OVER THE
W) AHEAD OF AN APPROACHING COLD FRONT WILL SLOWLY DIMINISH TONIGHT.
WINDS SHOULD MOSTLY DROP OFF BLO 20KT FOR MUCH OF WED AS THE COLD
FRONT ARRIVES. WITH THE PASSAGE OF COLD FRONT...NW WINDS WILL BE ON
THE INCREASE WED EVENING AND THEN THRU THU AS A FOLLOWING LOW PRES
CENTER PASSES SE ACROSS NRN ONTARIO. UNDER CAA/INCREASING OVERWATER
INSTABILITY...NW WINDS WILL INCREASE TO 20-30KT...ESPECIALLY THU/THU
NIGHT. GALES ARE A POSSIBILITY. WINDS WILL DIMINISH TO UNDER 20KT BY
LATE FRIDAY AFTN AS HIGH PRESSURE BUILDS INTO THE REGION. ON THE
BACKSIDE OF THE HIGH...SW WINDS WILL RAMP BACK UP TO 20-30KT SAT.
&&
.HYDROLOGY...
ISSUED AT 405 PM EST TUE MAR 6 2012
EVEN WITH THE WARM TEMPS OVER THE NEXT 24-36 HOURS...DON/T EXPECT
MUCH IF ANY MELTING TO OCCUR DUE TO THE UN-RIPE CONDITIONS OF THE
SNOW PACK. LOOKING AT NOHRSC CURRENT AND FUTURE SNOWPACK
TEMPERATURES...ONLY THE TOP AND MIDDLE LAYERS /TOP 2-10 INCHES
DEPENDING ON LOCATION/ OF THE SNOWPACK BECOME RIPE OVER THE SW HALF
OF THE CWA BY WED EVENING. THIS WILL LIKELY LEAD TO SOME
COMPACTION/MELTING OF THE TOP OF THE EXISTING SNOWPACK...BUT IT
SHOULD STILL RETAIN THE WATER AND KEEP MUCH OR ALL OF THE MOISTURE
IN THE SNOWPACK THROUGH WED EVENING.
WITH COOLER TEMPERATURES EXPECTED BEHIND THE COLD FRONT ON
WED...DON/T EXPECT ANY MELTING TO OCCUR WED NIGHT INTO SAT. WITH THE
WARMING TREND EXPECTED DURING THE WEEKEND AND INTO NEXT WEEK...WILL
NEED TO KEEP AN EYE ON A SLOWLY RIPENING SNOWPACK. THE POTENTIAL FOR
RAIN ON SUN/MON MAY ASSIST IN THIS RIPENING THROUGH THE FIRST PART
OF NEXT WEEK.
THE POTENTIAL FOR MELTING OF THE SNOWPACK COULD GREATLY INCREASE
HEADING INTO THE MIDDLE OF NEXT WEEK...AS OVERNIGHT LOWS AND TD
VALUES RISE ABOVE FREEZING. THE EXTENDED MODELS HAVE BEEN SHOWING
WELL ABOVE NORMAL TEMPERATURES /10 PLUS DEGREES/ FOR THE MIDDLE OF
NEXT WEEK. IF THE WARM TEMPS SHOWN ON THE ECMWF /HIGHS IN THE 60S
FOR WED AND THURS/ COME TO FRUITION...THE MELT MAY BE FAIRLY FAST
AND RUN OFF DIRECTLY INTO AREA RIVERS. THUS...WILL NEED TO KEEP AN
EYE ON AREA RIVERS AND STREAMS NEXT WEEK FOR THE POTENTIAL OF RISING
LEVELS DUE TO SNOWMELT.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...KC
SYNOPSIS...ROLFSON
SHORT TERM...ROLFSON
LONG TERM...SRF
AVIATION...KC
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
310 AM CST WED MAR 7 2012
.SHORT TERM...TODAY THROUGH FRIDAY NIGHT
310 AM CST WED MAR 7 2012
MAIN FORECAST CONCERNS ARE ON PRECIPITATION CHANCES TODAY INTO
TONIGHT AND TEMPERATURES THROUGH THE PERIOD.
LATEST SURFACE OBSERVATIONS SHOWED A COLD FRONT STRETCHING FROM
NORTH CENTRAL MINNESOTA SOUTHWEST INTO CENTRAL NEBRASKA.
THE COLD FRONT IS EXPECTED TO MOVE FROM WEST TO EAST ACROSS THE
FORECAST AREA THIS AFTERNOON. THE WARM SOUTHERLY FLOW WILL CONTINUE
ACROSS THE AREA THIS MORNING AHEAD OF THE FRONT. WITH VERY MILD
TEMPERATURES ALREADY IN PLACE ACROSS MUCH OF THE AREA THIS
MORNING...SHOULD HAVE NO PROBLEM WARMING INTO THE UPPER 50S TO LOWER
60S. ANOTHER CONCERN IS ON PLACEMENT OF PRECIPITATION AS THE FRONT
MOVES THROUGH. EARLY THIS MORNING...THE MOST OF THE CLOUD COVER WAS
POST FRONTAL WITH NO SIGNIFICANT PRECIPITATION BEING REPORTED.
HOWEVER...AS THE FRONT MOVES SOUTHEAST FRONTOGENESIS IS EXPECTED TO
INCREASE. THE FIRST BAND OF FRONTOGENESIS LOOKS TO SET UP IN THE
900-800 MB LEVEL. FORECAST SOUNDINGS SUPPORT LOW LEVEL SATURATION SO
SHOULD SEE THE DEVELOPMENT OF LIGHT RAIN ACROSS NORTHEAST
IOWA...SOUTHEAST MINNESOTA INTO WESTERN WISCONSIN THIS AFTERNOON.
THIS FRONTOGENESIS BAND APPEARS TO DEEPEN WITH TIME AS IT DRIFTS
SOUTHEAST INTO EXTREME NORTHEAST IOWA AND FAR SOUTHWEST WISCONSIN
LATE THIS AFTERNOON INTO THIS EVENING. SHOULD SEE THE RAIN BAND
BECOME MORE ORGANIZED AS IT MOVES SOUTHEAST DURING THE LATE
AFTERNOON INTO THE EVENING HOURS. EXTREME SOUTHWEST WISCONSIN MAY
PICK UP AROUND A QUARTER OF AN INCH OF RAINFALL OUT OF THIS SYSTEM
WITH 0.03 TO AROUND A TENTH OF INCH ELSEWHERE. PLAN ON FALLING
TEMPERATURES THIS AFTERNOON IN THE WAKE OF THE FRONT. THE RAIN IS
EXPECTED TO MOVE SOUTHEAST OF THE FORECAST AREA LATE THIS EVENING.
DEPENDING ON HOW QUICKLY THE COLDER AIR MOVES IN...WE COULD SEE
A BRIEF PERIOD OF LIGHT SNOW BEFORE THE PRECIPITATION ENDS. LOOK
FOR LOW TEMPERATURES TO RANGE FROM THE LOWER 20S ACROSS PORTIONS
OF NORTHEAST IOWA THROUGH NORTH CENTRAL WISCONSIN TO THE UPPER 20S
TO LOWER 30S ACROSS FAR SOUTHWEST WISCONSIN.
HIGH PRESSURE WILL EDGE INTO THE AREA LATE TONIGHT INTO THURSDAY.
850 MB TEMPERATURES WILL FALL 10 DEGREES FROM THIS AFTERNOON INTO
THURSDAY...WITH 850 MB TEMPS RANDING FROM -10 C ACROSS NORTH
CENTRAL WISCONSIN TO -5 C ACROSS NORTHEAST IOWA. AN UPPER LEVEL
TROUGH WILL SLIDE THROUGH THURSDAY AFTERNOON WITH THE POTENTIAL TO
BRING SOME CUMULUS CLOUDS TO THE AREA. PLAN ON HIGH TEMPERATURES
RANGING FROM THE UPPER 30S ACROSS NORTH CENTRAL WISCONSIN TO THE
LOWER 40S ACROSS NORTHEAST IOWA UNDER PARTLY SUNNY SKIES. FORECAST
SOUNDINGS ARE SHOWING THE POTENTIAL FOR A FEW RAIN/SNOW SHOWERS ON
THURSDAY WITH STEEP LAPS RATES IN PLACE. HOWEVER...LOW LEVEL
MOISTURE IS LACKING WITH TEMPERATURE/DEW POINT SPREADS OF 10
DEGREES ACROSS PORTIONS OF SOUTHEAST MINNESOTA INTO FAR SOUTHWEST
WISCONSIN. NORTH OF INTERSTATE 94...THERE MAY BE ENOUGH LOW LEVEL
MOISTURE TO PRODUCE VERTICALLY DEVELOPED CUMULUS TO PRODUCE LIGHT
RAIN OR SNOW SHOWERS. CONFIDENCE LOW ON THIS OCCURRING GIVEN HOW
DRY THE AIRMASS IS. WILL INCREASE CLOUD COVER ACROSS THESE AREAS
ON THURSDAY TO ACCOUNT FOR SHALLOW CUMULUS DEVELOPMENT. IT WILL BE
RATHER BREEZY ON THURSDAY WITH SURFACE LOW PRESSURE PASSING JUST
NORTH OF LAKE SUPERIOR AND HIGH PRESSURE ACROSS THE
DAKOTAS...PRODUCING A TIGHT PRESSURE GRADIENT ACROSS THE FORECAST
AREA. LOOK FOR WEST NORTHWEST WINDS OF 15 TO 25 MPH WITH GUSTS TO
AROUND 35 MPH. PLAN ON DECREASING CLOUDS THURSDAY EVENING AS
SURFACE COOLING COMMENCES. SURFACE HIGH PRESSURE WILL MOVE OVER
THE REGION ON FRIDAY PROVIDING SUNNY SKIES. LOOK FOR HIGH
TEMPERATURES TO RANGE FROM THE MID 30S ACROSS NORTH CENTRAL
WISCONSIN TO THE LOWER 40S ACROSS NORTHEAST IOWA. UPPER LEVEL
RIDGING IS EXPECTED TO PUSH INTO THE UPPER MISSISSIPPI RIVER
VALLEY FRIDAY NIGHT FROM THE NORTHERN PLAINS...WITH 850 MB
TEMPERATURES WARMING TO AROUND +6 C BY EARLY SATURDAY MORNING.
.LONG TERM...SATURDAY THROUGH TUESDAY
310 AM CST WED MAR 7 2012
UPPER LEVEL RIDGING IS EXPECTED ACROSS THE UPPER MISSISSIPPI RIVER
VALLEY ON SATURDAY AS AN UPPER LOW OVER THE FOUR CORNERS REGION
MEANDERS INTO THE CENTRAL PLAINS. PLAN ON HIGH TEMPERATURES ON
SATURDAY RANGING FROM THE UPPER 40S ACROSS NORTH CENTRAL WISCONSIN
TO THE LOWER 50S ACROSS WESTERN WISCONSIN INTO NORTHEAST IOWA.
07.00 MEDIUM RANGE MODELS CONTINUE TO SHOW DIFFERING SOLUTIONS
REGARDING THE THE EVOLUTION AND MOVEMENT OF THE FOUR CORNERS LOW
SATURDAY NIGHT INTO SUNDAY. THE ECMWF TAKES THE UPPER LOW INTO
EASTERN NEBRASKA SUNDAY AFTERNOON AND INTO THE FORECAST AREA
SUNDAY NIGHT. THE GFS IS A LITTLE FASTER AND BRINGS THE UPPER LOW
INTO CENTRAL IOWA SUNDAY AFTERNOON AND JUST BRUSHES SOUTHERN
PORTIONS OF THE FORECAST AREA SUNDAY NIGHT....WITH A SECOND UPPER
LOW DIVING SOUTH ACROSS SOUTHERN TEXAS. THE GEM LATCHES ONTO THE
SOUTHERN LOW SOLUTION AND TAKES THE LOW INTO TEXAS...LIFTING IT
INTO THE UPPER MISSISSIPPI RIVER VALLEY REGION SUNDAY NIGHT INTO
MONDAY. GIVEN THE SPREAD IN POTENTIAL SOLUTIONS WILL MAINTAIN A
MODEL CONSENSUS BLEND APPROACH SUNDAY INTO MONDAY. PLAN ON A
CHANCE OF RAIN ACROSS THE ENTIRE AREA SUNDAY INTO SUNDAY NIGHT
BEFORE THE LOW FINALLY EXITS THE AREA. WARM TEMPERATURES WILL
PERSIST MONDAY INTO TUESDAY WITH HIGHS IN THE 50S TO AROUND 60.
&&
.AVIATION...THROUGH 06Z THURSDAY
1135 PM CST TUE MAR 6 2012
MAIN CONCERN REMAINS ON ONSET OF LOW LEVEL SATURATION AND
CORRESPONDING CEILINGS HEIGHTS. FOG PRODUCT SATELLITE
IMAGERY...ALONG WITH SURFACE REPORTS INDICATE LITTLE IN THE WAY OF
STRATUS AS FAR SOUTH AS EASTERN KANSAS AND NORTHERN OKLAHOMA. A
SMALL BAND OF CLOUDS WITH CEILINGS AROUND 5K FEET WERE LIFTING
THROUGH CENTRAL IOWA. LATEST RUN OF THE RUC AND NAM MODELS HAVE
BACKED OFF ON MUCH LOW LEVEL SATURATION THROUGH THE OVERNIGHT
HOURS...WITH SATURATION NOW OCCURRING BETWEEN 12Z-18Z WEDNESDAY AT
BOTH TAF SITES. STILL EXPECT CEILINGS TO DROP INTO THE MVFR
CATEGORY AT KLSE AND IFR AT KRST...BUT DELAYED TO AROUND 15Z. COLD
FRONT MOVES THROUGH DURING THE AFTERNOON HOURS AND LIFT AHEAD OF
THE FRONT WILL RESULT IN SOME LIGHT RAIN THROUGH THE AFTERNOON AND
EVENING HOURS. RAIN SHOULD DIMINISHING BETWEEN 03Z-06Z
THURSDAY...WITH CEILINGS CLIMBING INTO THE MVFR CATEGORY AT KRST
AFTER 03Z.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
310 AM CST WED MAR 7 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...WETENKAMP
LONG TERM....WETENKAMP
AVIATION.....RABERDING
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1135 PM CST TUE MAR 6 2012
.SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT
254 PM CST TUE MAR 6 2012
MAIN FORECAST CONCERNS THIS PACKAGE...PRECIPITATION CHANCES WED...
TEMPERATURE THRU THE PERIOD.
18Z DATA ANALYSIS HAD A RATHER BROAD 995MB SFC LOW OVER THE DAKOTAS/
WY. PRESSURE GRADIENT AROUND THIS LOW COVERED MOST OF CENTRAL NOAM.
TIGHTER PRESSURE GRADIENT EAST OF THE LOW EXTENDED FROM TX TO THE
WESTERN GREAT LAKES...BRINGING WARM AND INCREASINGLY MOIST AIR
NORTHWARD INTO THE UPPER MIDWEST. WITH SUNNY SKIES...MINIMAL SNOW
OVER OVER IA/SOUTHERN MN/SOUTHWEST WI AND THE BRISK SOUTHWEST WINDS
FOR MIXING...EARLY AFTERNOON TEMPS IN THESE AREAS WERE IN THE 50S TO
NEAR 70...FOR AN EARLY TASTE OF SPRING. WITH THE DEEPER SNOW FROM
FEB 28/29...AND NORTH OF A WEAK WARM FRONT...TEMPS ACROSS CENTRAL
MN/NORTHERN WI MOSTLY IN THE UPPER 30S AND 40S.
NO MAJOR ERRORS NOTED WITH 06.12Z MODEL INITIALIZATIONS. BIGGEST
ERROR NOTED WAS GFS TOO FAR NORTHEAST/5 TO 10F TOO HIGH WITH THE
SFC DEW POINTS/MOISTURE PLUME IN EASTERN IA. SOLUTIONS QUITE SIMILAR
THRU 12Z THU BEFORE DIVERGING WITH THE EVOLUTION OF THE SOUTHERN
STREAM PORTION OF THE TROUGH OVER THE SOUTHWEST CONUS THU NIGHT INTO
FRI NIGHT. DPROG/DT OF 500MB HGTS AT 06.12Z SHOWED THE MODEL RUNS OF
04.12Z AND 05.12Z VERIFIED RATHER WELL ACROSS NOAM/EASTERN PAC WITH
ECMWF OFFERING THE BETTER RUN-TO-RUN CONSISTENCY. MODELS CONVERGING
ON A TIGHTER CONSENSUS SOLUTION TONIGHT THRU THU AS THE PAC COAST
TROUGH MOVES INTO WESTERN NOAM AND SPLITS...WITH THE NORTHERN STREAM
PORTION MOVING ACROSS THE UPPER MIDWEST WED NIGHT. GOOD CONSISTENCY
AMONG MODELS FOR HGTS TO RISE OVER THE NORTH-CENTRAL CONUS THU NIGHT
THRU FRI NIGHT BUT SAME CANNOT BE SAID FOR MODELS WITH THE SOUTHWEST
CONUS PORTION OF THE TROUGH. SOLUTIONS DIVERGING ON THOSE DETAILS
FRI/FRI NIGHT. ECMWF WITH THE BETTER RUN-TO-RUN CONSISTENCY TONIGHT
THRU FRI NIGHT. CHECK OF OBS VS. MODEL DATA AT 18Z SHOWED ALL QUITE
GOOD WITH THE DAKOTAS/WY LOW. GFS REMAINED TOO AGGRESSIVE BRINGING
HIGHER DEW POINTS INTO SOUTHWEST WI. PER WV IMAGERY...ALL LOOKED
GOOD AND COMPARABLE WITH THE SHORTWAVE ENERGY IN THE WESTERN CONUS
TROUGH. NO CLEAR MODEL FAVORITE BASED ON 18Z PERFORMANCE. WITH ECMWF
SHOWING THE BETTER RUN-TO-RUN CONSISTENCY...FAVORED A MODEL/ENSEMBLE
CONSENSUS WEIGHTED TOWARD THE ECMWF THIS CYCLE. SHORT-TERM FCST
CONFIDENCE AVERAGE TO GOOD THIS CYCLE.
FOR THE SHORT TERM...WARM SOUTHERLY FLOW WILL CONTINUE ACROSS THE
AREA TONIGHT...AHEAD OF THE LOW AND A COLD FRONT ADVANCING EAST
ACROSS THE NORTHERN PLAINS. LOWER LEVEL MOISTURE...SEEN AS STRATO-
CUMULUS OVER OK ADVANCES NORTH TONIGHT AS WELL. A MILD NIGHT
TONIGHT WITH GRADIENT WINDS KEEPING THE BOUNDARY LAYER STIRRED AND
INCREASING LOW CLOUDS AFTER MIDNIGHT. SOME CONCERN FOR FOG/-DZ LATE
TONIGHT...BUT GRADIENT WINDS WILL KEEP BOUNDARY LAYER STIRRED AND
THE INCREASING CLOUDS. BY 12Z MODEL SOUNDING SHOW MOISTURE TO ONLY
BE ABOUT 1KM DEEP...A BIT SHALLOW FOR -DZ. LATEST MODEL CONSENSUS
BRINGS THE COLD FRONT ACROSS THE AREA WED AFTERNOON. STRONGER OF
THE SFC-700MB FN CONVERGENCE IS ALONG/BEHIND THE FRONT...WITH
MOISTURE DEEPENING TO BETWEEN 800-700MB. TIGHTER MODEL CONSENSUS
SPREADS A MORE CONSISTENT LIFT/PRECIP SIGNAL SOUTHEAST ACROSS THE
FCST AREA LATE WED MORNING THRU WED EVENING...WITH DEEPEST OF
POST-FRONTAL MOISTURE ACROSS THE SOUTHEAST END OF THE FCST AREA WED
EVENING. DID ADD A -DZ MENTION TO THE NORTHWEST 2/3 OF THE FCST AREA
EARLY WED MORNING AHEAD OF THE FRONT WITH THE MOISTURE DEEPENING TO
ABOUT 800MB AFTER 12Z WED. RAISED -RA CHANCES ACROSS THE NORTHWEST
1/3 OF THE FCST AREA LATE WED MORNING...THEN RAISED -RA CHANCES TO
70-85 PERCENT ACROSS THE SOUTHEAST 3/4 OF THE FCST AREA FOR WED
AFTERNOON. GIVEN THE TOP OF THE MOISTURE BELOW 700MB...-RA AMOUNTS
WED LOOKING LIGHT. COLDER AIR SPREADS IN BEHIND THE FRONT WED NIGHT
WITH POTENTIAL FOR THE TRAILING EDGE OF THE PRECIP/-RA TO MIX
WITH/CHANGE TO -SN BEFORE ENDING. LITTLE IF ANY -SN ACCUMULATION
FROM THIS. DRIER/COOLER CAN HIGH PRESSURE BUILDS SOUTHEAST FOR THU
THRU FRI NIGHT. SUBSIDENCE/SFC-700MB DRYING SPREAD ACROSS THE AREA
LATER WED NIGHT/THU. 850-500MB SHORTWAVE RIDGING/ANTI-CYCLONIC FLOW
BUILD ACROSS THE AREA THU NIGHT-FRI NIGHT. THU THRU FRI NIGHT
TRENDING TO BE A CLEAR/MOSTLY CLEAR PERIOD. CENTER OF THE SFC HIGH
DRIFTS ACROSS THE AREA LATE THU NIGHT/FRI WITH 925MB TEMPS AT 12Z
FRI IN THE -2C TO -8C RANGE. DEPENDING ON HOW QUICKLY WINDS DECOUPLE
THU NIGHT...FRI MORNING LOWS COULD BE SEVERAL DEGREES COLDER THAN
THOSE THAT CURRENTLY BLEND WELL WITH THE NEIGHBORING FCST GRIDS.
LOW LEVEL WARM ADVECTION/WARMING 925MB TEMPS BEGIN TO SPREAD ACROSS
THE AREA FRI NIGHT ALONG WITH SOME SOUTH GRADIENT WINDS.
FAVORED A BLEND OF THE NUMERICAL GUIDANCE HIGHS/LOWS FOR TONIGHT
THRU FRI NIGHT. CONTINUED THE NON-DIURNAL TEMP TREND WED WITH HIGHS
LATE MORNING OR MID-DAY THEN FALLING AS THE FRONT/-RA PUSH INTO/
ACROSS THE AREA DURING THE AFTERNOON.
.LONG TERM...SATURDAY THROUGH TUESDAY
254 PM CST TUE MAR 6 2012
06.00Z MEDIUM RANGE MODELS ALREADY AT ODDS ON SAT WITH THE EVOLUTION
OF THE SOUTHWEST CONUS MID LEVEL LOW...AS ARE THE 06.12Z RUNS. GFS
MORE SPLIT WITH ONE PIECE OF ENERGY OVER OK/KS AND CA BAJA. OTHER
MODELS WITH ONE LOW/TROUGH OVER CO/AZ/NM. MODELS SHOWING MODEST
CONSISTENCY WITH THEIR PREVIOUS RUNS. THESE DIFFERENCES CONTINUE...
AND INCREASE...SUN AS SOME FORM OF THIS LOW/TROUGH LIFTS TOWARD OR
INTO THE MID/UPPER MS RIVER VALLEY...GFS FASTEST INTO THE OH VALLEY
WITH UKMET/GEM SLOWER AND STILL LIFTING INTO THE MID MS VALLEY AT
00Z MON. LOTS OF DETAIL DIFFERENCES BY MON/TUE IN THE FLOW OVER
CENTRAL/EASTERN NOAM BUT GENERAL CONSENSUS FOR HGTS TO RISE OVER THE
NORTH-CENTRAL CONUS. BETTER CONSENSUS WITH THE NEXT STRONG TROUGH TO
APPROACH/MOVE ONTO THE WEST COAST BY TUE. GIVEN THE DIFFERENCES WITH
THE HANDLING OF THE SOUTHWEST CONUS LOW/ENERGY ALREADY FRI/SAT...THE
LONG-TERM FCST CONFIDENCE IS BELOW AVERAGE THIS CYCLE. WILL SIDE
WITH THE PMDEPD IDEA THAT THE GFS IS AN OUTLIER AND FAVOR A
CONSENSUS OF THE ECMWF/GEM/UKMET/ENSEMBLES THAT EJECTS SOME PORTION
OF THE SOUTHWEST CONUS ENERGY INTO THE UPPER MIDWEST SUN. SHORTWAVE
RIDGING ALOFT BUILDS OVER THE REGION SAT WITH THE SFC HIGH MOVING
EAST OF THE AREA. SAT TRENDS DRY/WARMER WITH INCREASING SOUTH WINDS
ON THE WEST SIDE OF THE HIGH. SFC THRU MID LEVEL LOW EJECTING
NORTHEAST SAT NIGHT INTO SUN NIGHT/MON PULLS ABUNDANT GULF MOISTURE
NORTHWARD TOWARD AND INTO THE AREA. SOUNDINGS AND LOW LEVEL THERMAL
PROFILES INDICATE COLUMN WILL BE WARM ENOUGH THIS PERIOD THAT THE
BULK OF ANY PRECIP WITH THIS PASSING TROUGH WOULD BE RAIN. GOOD
CONSENSUS FOR DRIER HIGH PRESSURE/RIDGING ALOFT TO BE OVER THE
REGION TUE. PREFERRED A CONSENSUS OF MAX/MIN TEMP GUIDANCE WEIGHTED
TOWARD THE NON-GFS MODELS.
&&
.AVIATION...THROUGH 06Z THURSDAY
1135 PM CST TUE MAR 6 2012
MAIN CONCERN REMAINS ON ONSET OF LOW LEVEL SATURATION AND
CORRESPONDING CEILINGS HEIGHTS. FOG PRODUCT SATELLITE
IMAGERY...ALONG WITH SURFACE REPORTS INDICATE LITTLE IN THE WAY OF
STRATUS AS FAR SOUTH AS EASTERN KANSAS AND NORTHERN OKLAHOMA. A
SMALL BAND OF CLOUDS WITH CEILINGS AROUND 5K FEET WERE LIFTING
THROUGH CENTRAL IOWA. LATEST RUN OF THE RUC AND NAM MODELS HAVE
BACKED OFF ON MUCH LOW LEVEL SATURATION THROUGH THE OVERNIGHT
HOURS...WITH SATURATION NOW OCCURRING BETWEEN 12Z-18Z WEDNESDAY AT
BOTH TAF SITES. STILL EXPECT CEILINGS TO DROP INTO THE MVFR
CATEGORY AT KLSE AND IFR AT KRST...BUT DELAYED TO AROUND 15Z. COLD
FRONT MOVES THROUGH DURING THE AFTERNOON HOURS AND LIFT AHEAD OF
THE FRONT WILL RESULT IN SOME LIGHT RAIN THROUGH THE AFTERNOON AND
EVENING HOURS. RAIN SHOULD DIMINISHING BETWEEN 03Z-06Z
THURSDAY...WITH CEILINGS CLIMBING INTO THE MVFR CATEGORY AT KRST
AFTER 03Z.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
254 PM CST TUE MAR 6 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...RRS
LONG TERM....RRS
AVIATION...RABERDING
AREA FORECAST DISCUSSION...UPDATED
NWS TALLAHASSEE FL
614 AM EST Wed Mar 7 2012
.UPDATE...Aviation discussion for the 12Z TAFs.
&&
.SYNOPSIS...
08Z water vapor and H4 RUC analysis shows an upper level pattern
consisting of amplified and sharp troughing over the inter-mountain
west, followed downstream by broad longwave ridging over the eastern
half of the CONUS. A weak shortwave impulse is analyzed ejecting
eastward from the main western trough over the southern plains this
morning. Only influence we will see from this impulse is some high
level cirrus streaming overhead to filter the sunshine at times.
Overall the troposphere is still quite dry below this cirrus shown
by the 00Z KTLH sounding.
At the surface, strong 1040mb high pressure centered along the NC
coast continues to ridge back to the west and southwest. Our
position on the southern side of the ridge axis is providing a
steady easterly flow along the NE Gulf coast. The tight gradient is
resulting in a significant nocturnal easterly surge over the coastal
waters this morning, with both buoys gusting to near 30 knots at
times. Similar to Monday night, the breezy conditions are helping to
keep the boundary layer well mixed and our temperatures up. Most
locations are still reporting mid/upper 50s, and do not anticipate
many stations dropping below the upper 40s before sunrise.
&&
.SHORT TERM (Today through Friday)...
Today and Tonight,
Another pleasant and generally dry day upcoming. Weak upper level
ridging will remain in place along the northern Gulf coast, while
surface high pressure is centered well to our NE. On Tuesday we saw
excellent diurnal mixing up to around 800mb, and anticipate similar
mixing conditions today. Mixing up to between 850-800mb will yield
high temperatures generally in the lower to middle 70s. East to
southeast flow should keep temps a few degrees cooler along the
coast from Franklin county westward. Skies will generally end up
partly cloudy as periods of high level cirrus overspread the area
from west to east, and lower level high based cumulus develop in the
fast easterly flow. Hi-res CAM ensembles suggest the development of
a few low topped speed convergence showers across NE Florida/SE
Georgia this afternoon. Not impossible that a brief sprinkle could
make it as far east as the Suwannee River Valley/I-75 Corridor,
however any sprinkles would be of very low impact and will only go
with a silent 10% PoP over our far eastern zones. Due to the strong
easterly flow over the coastal waters, waves refracting back toward
the panhandle coast are expected to produce a high rip current risk
along the panhandle beaches of Walton county. Dry and seasonable
condition tonight with low temps holding in the 50s.
Thursday/Thursday night,
Western U.S upper trough is progged to fracture by Thursday morning
with the southern energy cutting over New Mexico, and the northern
fracture progressing quickly eastward over the Great Lakes/Ohio
Valley. In response to the height falls over the Southern Plains in
advance of the cutoff low, a brief amplification of the ridge over
the Southeastern States will occur. Under the upper ridge we will
experience a dry, pleasant, and even warmer day. 850mb temps rising
to 10-12C and decent diurnal mixing will result in afternoon high
temps rising well into the 70s, with a few 80 degree readings
possible. A weaken gradient during the afternoon hours combined with
the mid/upper 70 temps should result in the development of a feeble
sea-breeze. This flow will again keep temps along the immediate
coast cooler. Upper trough moving into the eastern U.S. Thursday
night/early Friday will begin to break down the upper ridge while
also progressing a weak surface trough into northern AL/GA. At this
time, NWP guidance is in good agreement that any shower activity
associated with this front will remain to our north Thursday night
giving our region a dry and warm overnight period. Low temps in the
mid/upper 50s inland and lower 60s at the coast.
Friday,
Weak upper level impulse will approach the area while the surface
front progresses into our zones. Overall the forcing with this
system is weak which should prevent any organized area of rainfall.
However, with at least some surface focus, and decent instability
progged by the global models(600-1200 J/kg), will expect isolated to
scattered convection during the day. Not expecting a wet forecast,
but those with outdoor activities should plan for the potential of a
passing shower or storm. Outside of the scattered showers, Friday
looks to be a warm and muggy day with temperatures within a few
degrees of 80 away from the immediate coast.
&&
.LONG TERM (Saturday through next Wednesday)...
Overall confidence in this part of the forecast remains below normal
although we are beginning to see at least a modicum of agreement
among a couple of the models. The good news is that the 00Z
operational runs of the GFS and Euro are in better agreement than
last night at this time. Both now show an upper low moving northeast
across the Central Plains at the start of the period with additional
energy hanging back to the southwest. As the plains feature lifts
rapidly northeast toward the Upper Great Lakes by Sunday night, the
southern energy swings east across TX. By Monday, model differences
creep in once again with the GFS bringing a tighter system northeast
up the MS Valley and the new Euro bringing a much weaker system east
across the Gulf states.
At the surface, a front will be positioned just northwest of the
forecast area at the start of the period as an inverted trough
develops over the western Gulf. A strong ridge will build east to
the Mid Atlantic coast on Saturday and force the frontal boundary
through the area and thus returning the forecast area to the
easterly flow regime we are currently experiencing. The ridge will
only slowly drift south into the early to middle part of next week.
However, it does appear to be a deep enough feature to hold any
significant boundaries and upper energy west of the area.
PoPs will be tapered a bit for most periods with a nod toward the
MEX numbers now that the GFS is approximated by the Euro. With few
obvious forcing mechanisms, will hold PoPs mainly in the 20-30
percent range through Tuesday. With the ridging in place for most of
the period, temperature will be above normal for the most part. One
exception will be Saturday when the back door cold frontal passage
will keep max temps in the 60s north of a line from Valdosta to
Dothan. A few of our northeastern zones will not get out of the
lower 60s. Further south, the FL zones will reach the 70s with the
Southeast Big Bend reaching the upper 70s. A moderating trend in
temps will commence across the northern zones on Sunday with
everyone well above normal once again for the Monday through
Wednesday period.
&&
.AVIATION (Through 12Z Thursday)...
VFR conditions are forecast to prevail across the forecast area
until late in the TAF period. The low level easterly flow regime
will continue on the south side of a surface high that is centered
off the Mid Atlantic coast and ridges southwestward to the eastern
Gulf Coast. Areas of stratus are already moving westward across
northeast FL and southeast GA and some of these clouds have already
reached the eastern terminals. We are forecasting a VFR ceiling at
VLD and ABY shortly later this morning. This ceiling may spread west
over the remaining terminals by the end of the day. We have included
the possibility for MVFR conditions developing toward the end of the
TAF period tonight after 08Z. Confidence is better than this morning
that this will actually occur, but we still show the condition as
temporary.
&&
.MARINE...
A tight gradient on the southern periphery of strong 1040mb high
pressure will continue to result in advisory level winds and seas
over the coastal waters this morning. Winds and seas will begin to
subside this afternoon, especially to the east of of Apalachicola.
Another easterly surge is expected tonight, but only to cautionary
levels. Winds and seas will drop below headline criteria later
Thursday into Friday ahead of an approaching weak front. This front
will wash out over the coastal waters during Saturday with moderate
easterly flow re-developing for the second half of the upcoming
weekend.
&&
.FIRE WEATHER...
An increase in RH today will preclude red flag conditions from being
reached, even across our FL zones. In fact, we see no red flag
events in the offing for the remainder of this week and on into
early next week.
&&
.PRELIMINARY POINT TEMPS/POPS...
Tallahassee 75 52 78 55 80 / 0 0 0 0 20
Panama City 73 57 74 61 74 / 0 0 0 10 30
Dothan 75 53 78 58 78 / 0 0 0 10 40
Albany 73 52 77 57 78 / 0 0 0 10 30
Valdosta 74 52 78 55 80 / 10 0 0 0 20
Cross City 78 52 80 56 81 / 10 0 10 0 20
Apalachicola 69 59 71 62 71 / 0 0 0 0 20
&&
.TAE WATCHES/WARNINGS/ADVISORIES...
AL...None.
GA...None.
FL...None.
GM...Small Craft Advisory until 5 PM EST this afternoon for Coastal
waters From Ochlockonee River to Apalachicola FL out to 20
NM-Coastal waters from Apalachicola to Destin FL out 20 NM-
Waters from Suwannee River to Apalachicola FL from 20 to 60
NM-Waters from Apalachicola to Destin FL from 20 to 60 NM.
&&
$$
Synopsis/Short Term/Marine...Mroczka
Long Term/Aviation/Fire Wx...Wool
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
923 AM CST WED MAR 7 2012
...UPDATED FOR AVIATION...
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 403 AM CST WED MAR 7 2012
SYNOPSIS:
AT 00Z LAST NIGHT...A LARGE ANTICYCLONICALLY CURVED JET EXTENDED FROM
THE SOUTHERN COAST OF ALASKA TO THE ALBERTA ROCKIES
SOUTH-SOUTHWESTWARD TO NEAR SAN FRANCISCO LEADING TO THE DEVELOPING
MID LEVEL CYCLONE...WHICH WAS CENTERED OVER THE SIERRA NEVADA AT
THAT TIME. 150 TO 200 METER 12-HOUR HEIGHT FALLS WERE FOUND AHEAD
OF THE DEVELOPING CYCLONE AT 500MB. COLD MID LEVELS WERE ALSO
OBSERVED WITH 700MB TEMPERATURES -15 TO -18C ACROSS EASTERN
WASHINGTON AND OREGON TO WESTERN MONTANA AND NORTHERN NEVADA. AHEAD
OF THE DEVELOPING CYCLONE...700MB TEMPERATURES WERE +5 TO +7C OVER
THE SOUTHERN ROCKIES AND SOUTHERN PLAINS. AT 00Z...THE 850MB FRONT
EXTENDED SOUTHWEST FROM A LOW CENTER NEAR THE MANITOBA-NORTH
DAKOTA-MINNESOTA BORDER TO THE BLACK HILLS REGION. AS OF 09Z...THE
FRONT AT THE SURFACE EXTENDED FROM NEAR SIOUX FALLS, SOUTH DAKOTA
SOUTHWEST WARD TO NORTHWEST KANSAS. THE FRONT HAD JUST PASSED
THROUGH GOODLAND, KS WITH A NORTH-NORTHWEST WIND OBSERVED.
TODAY:
THE FRONT WILL CONTINUE TO PUSH SOUTH...REACHING AN ELKHART TO
GARDEN CITY TO LACROSSE LINE BY LATE MORNING. TEMPERATURES WILL
FALL ABRUPTLY UPON THE INITIAL PASSAGE OF THE FRONT...THEN CONTINUE
A SLOW DECLINE OR HOLD NEARLY STEADY FOR THE REMAINDER OF THE DAY AS
WARMING THROUGH INSOLATION IS OFFSET BY COLD ADVECTION. BY LATE
AFTERNOON...THE UPPER LOW WILL STILL BE WELL TO THE WEST OVER THE
FOUR CORNERS. NO MEASURABLE PRECIPITATION IS EXPECTED DURING THE
"TODAY" PERIOD (ENDING 00Z) AND HAVE REMOVED ALL POPS AS A RESULT
FOR TODAY. SOME OF THE SHORT TERM HIGH RESOLUTION MODELS DO HINT AT
SOME PATCHY DRIZZLE/REAL LIGHT SHOWERS ACROSS CENTRAL KANSAS PERHAPS
CLIPPING STAFFORD COUNTY BY LATE AFTERNOON... AND I DO HAVE SOME
"SILENT" POPS LESS THAN 15 PERCENT TO COVER THIS...BUT ANY
MEASURABLE PRECIPITATION SHOULD HOLD OFF UNTIL AFTER 00Z.
TONIGHT:
A REALLY COMPLICATED FORECAST FOR TONIGHT. ALL THE MODELS HAVE
TRENDED DOWNWARD IN PRECIPITATION POTENTIAL/AMOUNTS FOR THE MAJORITY
OF THE DDC FORECAST AREA AND AS A RESULT...POPS HAVE BEEN LOWERED
ACROSS THE BOARD. IN FACT...AREAS NORTHWEST OF A LAKIN TO GARDEN
CITY TO JETMORE LINE MAY NOT SEE MUCH IN THE WAY OF PRECIPITATION AT
ALL TONIGHT. AS THE FRONT CONTINUES TO PUSH SOUTH INTO
OKLAHOMA...DRIER AIR WILL BE MOVING IN. SHOWERS AND THUNDERSTORMS
WILL EVENTUALLY DEVELOP ALONG THE FRONT IN THE 850-900MB LAYER AS
INDICATED BY ECMWF, GFS, AND CANADIAN GEM...BUT THIS WILL MOST
LIKELY BE REALIZED ACROSS THE FAR SOUTHEASTERN COUNTIES (COMANCHE
AND BARBER). ELEVATED CAPE FROM AN 800MB PARCEL WOULD SUGGEST
AROUND 400-600 J/KG UP INTO BARBER COUNTY...SO SOME SMALL HAIL
WITH ANY CONVECTION WILL BE POSSIBLE. OTHER LIGHTER SHOWERS MAY DEVELOP
FARTHER NORTH WHERE THE FRONTOGENESIS EXISTS HIGHER UP IN THE
TROPOSPHERE WITH THE SLOPING COLD FRONT...BUT ALL MODELS INSIST
THAT THE MORE SUBSTANTIAL PRECIPITATION PRODUCTION WILL BE TIED TO
FRONTOGENESIS LOWER IN THE TROPOSPHERE...AND THUS FARTHER SOUTH.
WILL KEEP THE AREAS OF DRIZZLE/LIGHT FREEZING DRIZZLE IN THE GRIDS
FOR ROUGHLY THE SOUTHEASTERN HALF AS THE NAM AND SOME VERSIONS OF
THE WRF SUGGEST THE LIGHT PRECIPITATION SIGNAL IN SIMULATED
REFLECTIVITY FIELDS. THAT BEING SAID...THE DRY AIR ADVECTION FROM
THE NORTH MAY JUST BE TOO MUCH TO OVERCOME AS THE STRONGEST
900-800MB FRONTOGENESIS WILL BE, AGAIN, SOUTH OF THE DDC FORECAST
AREA BY LATE IN THIS PERIOD. ANY SHALLOW LAYER PRECIPITATION
SHOULD BE FAIRLY SHORT-LIVED AND MOVE SOUTH OF THE AREA BY 12Z OR
SHORTLY THEREAFTER.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 231 AM CST WED MAR 7 2012
THURSDAY:
THE UPPER LEVEL LOW WILL BE SOUTH OF THE DDC FORECAST AREA. NAM/GFS
AN TOO A LESSER EXTENT THE GEM KEEP MOST OF THE HEAVIER
PRECIPITATION SOUTH OF THE AREA. THE 00Z ECMWF IS A LITTLE BIT MORE
GENEROUS WITH QPF. DECIDED TO KEEP CHANCE POPS ACROSS THE REGION. AN
EXAMINATION OF FORECAST SOUNDINGS SHOW THAT THE LOW LEVELS BELOW 700
HPA ARE SUB-SATURATED AND THE DENDRITIC LAYER IS NOT REALLY
SATURATED EITHER. DECIDED TO KEEP DRIZZLE AND FREEZING DRIZZLE IN
THE FORECAST SHOULD THE CLOUD DECK BECOME THICK ENOUGH. WARMED HIGHS
UP GIVEN THE MORE DRY SOLUTION THAT THE MODELS HAVE TURNED TO.
FRIDAY:
THE 00Z ECMWF DOESN`T MOVE UPPER LEVEL LOW THAT MUCH FRIDAY AND IS
WAY LESS PROGRESSIVE THAN COMPARED TO THE NAM/GFS. AS A RESULT, KEPT
SOME SOME SLIGHT TO CHANCE POPS ACROSS SOUTHWEST KANSAS. THE EURO
DOES INDICATE SOME SNOWFALL ACROSS EXTREME SOUTHWEST KANSAS.
SOMETHING TO WATCH AS NONE OF THE OTHER MODELS SUGGEST SUCH
ACCUMULATIONS.
WEEKEND AND BEYOND:
CONFIDENCE IS LOW THIS FAR OUT. SOME SHOWERS ARE POSSIBLE SATURDAY
IF THE ECMWF PANS OUT. OTHERWISE, THE FORECAST WILL DRY OUT AND
TEMPERATURES WILL WARM UP AS 500 HPA HEIGHTS INCREASE AND LOW LOW
THICKNESS FIELDS INCREASE AS WELL. TEMPERATURE LOOK TO BE ABOVE
NORMAL AT THE END OF THE PERIOD.
&&
.AVIATION...(FOR THE 15Z TAFS THROUGH 15Z THURSDAY MORNING)
ISSUED AT 918 AM CST WED MAR 7 2012
SURFACE OBSERVATIONS IS SHOWING THE FRONT IS MOVING FASTER THAN MODELS
SUGGEST. HRRR SEEMS TO BE DOING BETTER WITH THE FRONT TIMING AND WAS
USED IN THE 12Z TAFS. MVFR CIGS WILL GRADUALLY MOVE SOUTH ACROSS
HAYS AND GARDEN CITY BY 18Z. THEN POSSIBLE INTO KDDC BY 20Z. LATER
TONIGHT MVFR CIGS ARE EXPECTED IN ASSOCIATION WITH STRATUS AND
FREEZING DRIZZLE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 54 31 44 30 / 10 40 40 40
GCK 43 30 42 27 / 0 20 50 30
EHA 44 27 38 25 / 0 30 60 50
LBL 52 30 38 26 / 0 40 50 40
HYS 45 30 49 29 / 10 20 20 20
P28 66 36 45 35 / 10 70 70 30
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...UMSCHEID
LONG TERM....SUGDEN
AVIATION...KRUSE
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
500 AM CST WED MAR 7 2012
...UPDATE TO AVIATION FOR 12Z TAFS...
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 403 AM CST WED MAR 7 2012
SYNOPSIS:
AT 00Z LAST NIGHT...A LARGE ANTICYCLONICALLY CURVED JET EXTENDED FROM
THE SOUTHERN COAST OF ALASKA TO THE ALBERTA ROCKIES
SOUTH-SOUTHWESTWARD TO NEAR SAN FRANCISCO LEADING TO THE DEVELOPING
MID LEVEL CYCLONE...WHICH WAS CENTERED OVER THE SIERRA NEVADA AT
THAT TIME. 150 TO 200 METER 12-HOUR HEIGHT FALLS WERE FOUND AHEAD
OF THE DEVELOPING CYCLONE AT 500MB. COLD MID LEVELS WERE ALSO
OBSERVED WITH 700MB TEMPERATURES -15 TO -18C ACROSS EASTERN
WASHINGTON AND OREGON TO WESTERN MONTANA AND NORTHERN NEVADA. AHEAD
OF THE DEVELOPING CYCLONE...700MB TEMPERATURES WERE +5 TO +7C OVER
THE SOUTHERN ROCKIES AND SOUTHERN PLAINS. AT 00Z...THE 850MB FRONT
EXTENDED SOUTHWEST FROM A LOW CENTER NEAR THE MANITOBA-NORTH
DAKOTA-MINNESOTA BORDER TO THE BLACK HILLS REGION. AS OF 09Z...THE
FRONT AT THE SURFACE EXTENDED FROM NEAR SIOUX FALLS, SOUTH DAKOTA
SOUTHWEST WARD TO NORTHWEST KANSAS. THE FRONT HAD JUST PASSED
THROUGH GOODLAND, KS WITH A NORTH-NORTHWEST WIND OBSERVED.
TODAY:
THE FRONT WILL CONTINUE TO PUSH SOUTH...REACHING AN ELKHART TO
GARDEN CITY TO LACROSSE LINE BY LATE MORNING. TEMPERATURES WILL
FALL ABRUPTLY UPON THE INITIAL PASSAGE OF THE FRONT...THEN CONTINUE
A SLOW DECLINE OR HOLD NEARLY STEADY FOR THE REMAINDER OF THE DAY AS
WARMING THROUGH INSOLATION IS OFFSET BY COLD ADVECTION. BY LATE
AFTERNOON...THE UPPER LOW WILL STILL BE WELL TO THE WEST OVER THE
FOUR CORNERS. NO MEASURABLE PRECIPITATION IS EXPECTED DURING THE
"TODAY" PERIOD (ENDING 00Z) AND HAVE REMOVED ALL POPS AS A RESULT
FOR TODAY. SOME OF THE SHORT TERM HIGH RESOLUTION MODELS DO HINT AT
SOME PATCHY DRIZZLE/REAL LIGHT SHOWERS ACROSS CENTRAL KANSAS PERHAPS
CLIPPING STAFFORD COUNTY BY LATE AFTERNOON... AND I DO HAVE SOME
"SILENT" POPS LESS THAN 15 PERCENT TO COVER THIS...BUT ANY
MEASURABLE PRECIPITATION SHOULD HOLD OFF UNTIL AFTER 00Z.
TONIGHT:
A REALLY COMPLICATED FORECAST FOR TONIGHT. ALL THE MODELS HAVE
TRENDED DOWNWARD IN PRECIPITATION POTENTIAL/AMOUNTS FOR THE MAJORITY
OF THE DDC FORECAST AREA AND AS A RESULT...POPS HAVE BEEN LOWERED
ACROSS THE BOARD. IN FACT...AREAS NORTHWEST OF A LAKIN TO GARDEN
CITY TO JETMORE LINE MAY NOT SEE MUCH IN THE WAY OF PRECIPITATION AT
ALL TONIGHT. AS THE FRONT CONTINUES TO PUSH SOUTH INTO
OKLAHOMA...DRIER AIR WILL BE MOVING IN. SHOWERS AND THUNDERSTORMS
WILL EVENTUALLY DEVELOP ALONG THE FRONT IN THE 850-900MB LAYER AS
INDICATED BY ECMWF, GFS, AND CANADIAN GEM...BUT THIS WILL MOST
LIKELY BE REALIZED ACROSS THE FAR SOUTHEASTERN COUNTIES (COMANCHE
AND BARBER). ELEVATED CAPE FROM AN 800MB PARCEL WOULD SUGGEST
AROUND 400-600 J/KG UP INTO BARBER COUNTY...SO SOME SMALL HAIL
WITH ANY CONVECTION WILL BE POSSIBLE. OTHER LIGHTER SHOWERS MAY DEVELOP
FARTHER NORTH WHERE THE FRONTOGENESIS EXISTS HIGHER UP IN THE
TROPOSPHERE WITH THE SLOPING COLD FRONT...BUT ALL MODELS INSIST
THAT THE MORE SUBSTANTIAL PRECIPITATION PRODUCTION WILL BE TIED TO
FRONTOGENESIS LOWER IN THE TROPOSPHERE...AND THUS FARTHER SOUTH.
WILL KEEP THE AREAS OF DRIZZLE/LIGHT FREEZING DRIZZLE IN THE GRIDS
FOR ROUGHLY THE SOUTHEASTERN HALF AS THE NAM AND SOME VERSIONS OF
THE WRF SUGGEST THE LIGHT PRECIPITATION SIGNAL IN SIMULATED
REFLECTIVITY FIELDS. THAT BEING SAID...THE DRY AIR ADVECTION FROM
THE NORTH MAY JUST BE TOO MUCH TO OVERCOME AS THE STRONGEST
900-800MB FRONTOGENESIS WILL BE, AGAIN, SOUTH OF THE DDC FORECAST
AREA BY LATE IN THIS PERIOD. ANY SHALLOW LAYER PRECIPITATION
SHOULD BE FAIRLY SHORT-LIVED AND MOVE SOUTH OF THE AREA BY 12Z OR
SHORTLY THEREAFTER.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 231 AM CST WED MAR 7 2012
THURSDAY:
THE UPPER LEVEL LOW WILL BE SOUTH OF THE DDC FORECAST AREA. NAM/GFS
AN TOO A LESSER EXTENT THE GEM KEEP MOST OF THE HEAVIER
PRECIPITATION SOUTH OF THE AREA. THE 00Z ECMWF IS A LITTLE BIT MORE
GENEROUS WITH QPF. DECIDED TO KEEP CHANCE POPS ACROSS THE REGION. AN
EXAMINATION OF FORECAST SOUNDINGS SHOW THAT THE LOW LEVELS BELOW 700
HPA ARE SUB-SATURATED AND THE DENDRITIC LAYER IS NOT REALLY
SATURATED EITHER. DECIDED TO KEEP DRIZZLE AND FREEZING DRIZZLE IN
THE FORECAST SHOULD THE CLOUD DECK BECOME THICK ENOUGH. WARMED HIGHS
UP GIVEN THE MORE DRY SOLUTION THAT THE MODELS HAVE TURNED TO.
FRIDAY:
THE 00Z ECMWF DOESN`T MOVE UPPER LEVEL LOW THAT MUCH FRIDAY AND IS
WAY LESS PROGRESSIVE THAN COMPARED TO THE NAM/GFS. AS A RESULT, KEPT
SOME SOME SLIGHT TO CHANCE POPS ACROSS SOUTHWEST KANSAS. THE EURO
DOES INDICATE SOME SNOWFALL ACROSS EXTREME SOUTHWEST KANSAS.
SOMETHING TO WATCH AS NONE OF THE OTHER MODELS SUGGEST SUCH
ACCUMULATIONS.
WEEKEND AND BEYOND:
CONFIDENCE IS LOW THIS FAR OUT. SOME SHOWERS ARE POSSIBLE SATURDAY
IF THE ECMWF PANS OUT. OTHERWISE, THE FORECAST WILL DRY OUT AND
TEMPERATURES WILL WARM UP AS 500 HPA HEIGHTS INCREASE AND LOW LOW
THICKNESS FIELDS INCREASE AS WELL. TEMPERATURE LOOK TO BE ABOVE
NORMAL AT THE END OF THE PERIOD.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 500 AM CST WED MAR 7 2012
SURFACE OBSERVATIONS IS SHOWING THE FRONT IS MOVING FASTER THAN MODELS
SUGGEST. HRRR SEEMS TO BE DOING BETTER WITH THE FRONT TIMING AND WAS
USED IN THE 12Z TAFS. VFR CIGS WILL REMAIN TODAY, HOWEVER, CIGS WILL
LOWER TO MVFR...PARTICULARLY AT KDDC LATE TONIGHT IN ASSOCIATION WITH
STRATUS AND FREEZING DRIZZLE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 59 31 41 29 / 10 40 40 40
GCK 49 30 40 27 / 0 20 50 30
EHA 56 27 32 23 / 0 30 60 50
LBL 60 30 33 26 / 0 40 50 40
HYS 56 30 49 29 / 10 20 20 20
P28 71 36 43 34 / 10 70 70 30
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...UMSCHEID
LONG TERM....SUGDEN
AVIATION...SUGDEN
AREA FORECAST DISCUSSION...UPDATED
NWS MARQUETTE MI
1001 AM EST WED MAR 7 2012
.UPDATE...
ISSUED AT 959 AM EST WED MAR 7 2012
MADE SOME MINOR ADJUSTMENTS TO THE FORECAST...LARGELY TO DEAL WITH
THE TEMPERATURES AND FOG. NOT MUCH FOG ACROSS UPPER MI AND WI THIS
MORNING AND IT APPEARS TO BE LARGELY ASSOCIATED WITH THE SFC FRONT
FARTHER W NEAR KDLH. THUS...HAVE TAPERED BACK FOG MENTION TO BE
LOCATED ALONG THE FRONTAL BOUNDARY. DID LEAVE MENTION ALONG LK MI
THIS AFTN...AS WARM MOIST AIR WILL BE MOVING ACROSS THE RELATIVELY
COOL LK MI WATERS. DID RAISE HIGHS A COUPLE DEGREES FOR TODAY...AS
LIMITED FALL OVERNIGHT HAS KEPT VALUES IN THE 40S AND LOW 50S THIS
MORNING. THINK THE INCREASING CLOUDS AND PCPN STARTING TO DEVELOP
ALONG THE MN/WI BORDER BETWEEN KMSP-KDLH WILL KEEP TEMPS FROM RISING
MUCH ABOVE THE LOW 50S.
&&
.SYNOPSIS...
ISSUED AT 523 AM EST WED MAR 7 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A POSITIVE TILT MID/UPPER
LEVEL TROUGH FROM SASK/MANITOBA TOWARD A CLOSED LOW OVER SRN NEVADA
RESULTING IN SW FLOW FROM THE CNTRL PLAINS TO THE WRN GREAT LAKES.
AT THE SFC...A TROUGH/FRONT EXTENDED FROM NW ONTARIO AND NE MN INTO
ERN NEBRASKA. SOME LIGHT SNOW HAD DEVELOPED BEHIND THE FRONT OVER
ERN ND INTO FAR NW MN. OTHERWISE...NO PCPN WAS OBSERVED ALONG OR
AHEAD OF THE FRONT. VERY MILD AIR HAD SPREAD INTO THE REGION AHEAD
OF THE FRONT ON SSW WINDS WITH TEMPS OVERNIGHT CLIMBING INTO THE 40S
ACROSS MUCH OF WEST AND CENTRAL UPPER MI. BNDRY LAYR MIXING HAS
HELPED KEEP DEWPOINT DEPRESSIONS HIGH ENOUGH TO LIMIT ANY FOG
DEVELOPMENT.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 523 AM EST WED MAR 7 2012
MODELS HAVE CONTINUED WITH TREND TOWARD A LATER ARRIVAL OF THE
FRONT...MOVING INTO IWD AFT 18Z AND TO MQT-IMT BY 00Z. MOISTURE CONV
AND 900-700 MB FGEN ASSOCIATED WITH THE FRONT SHOULD BE ENOUGH TO
SUPPORT DEVELOPMENT AND INCREASING COVERAGE OF LIGHT PCPN BAND
THROUGH WRN UPPER MI IN THE AFTERNOON. PCPN MAY ALSO SPREAD INTO THE
ERN PORTION OF THE CWA WITH 290K-295K ISENTROPIC ASCENT AHEAD OF THE
FRONT. FCST SOUNDINGS SUPPORT LIQUID PCPN OVER MOST OF THE AREA WITH
POTENTIAL FOR CHANGEOVER TO FROZEN PCPN OVER THE FAR WEST LATE. WITH
A SUBSTANTIAL DRY 750-600 MB LAYER AND FREEZING LEVEL ABOVE THE MOIST
LAYER...LACK OF ICE CRYSTALS WOULD LEAD TO LIGHT ACCUMULATIONS OF
MAINLY DRIZZLE. THE NAM/GFS SUGGEST THAT A SHORTWAVE AND STRONGER
850-600 MB FGEN BEHIND THE FRONT WILL REMAIN MAINLY TO THE NW OF THE
CWA...STREAKING THROUGH NW LAKE SUPERIOR.
ENOUGH OF A COLD LAYER MAY DEVELOP BEHIND THE FRONT BY LATE
AFTERNOON WEST AND INTO THE EVENING CENTRAL WITH A SMALL LAYER NEAR
800-750 MB AT OR ABOVE 0C FOR A VERY BRIEF PERIOD OF SOME SLEET.
HOWEVER...ONCE THE DEEPER MOISTURE AND COLD AIR ARRIVE FROM WEST TO
EAST...THE PRECIP TYPE SHOULD CHANGE OVER FROM DZ/PL TO SNOW. WITH
ONLY A BRIEF PERIOD FOR ANY SNOW POSSIBLE...ANY ACCUMULATIONS SHOULD
AMOUNT TO LESS THAN A HALF INCH. LAKE ENHANCED SNOW POTENTIAL OVER
THE WEST WITH NW FLOW BEHIND THE FRONT WILL BE LIMITED BY THE
MARGINAL INSTABILITY AND QUICK ARRIVAL OF DRIER AIR AND LOW INVERSIO
HEIGHTS NEAR 3K FT.
THURSDAY...AS THE MID LEVEL TROUGH SLIDES INTO THE AREA MODERATE TO
STRONG 850-500 MB QVECTOR CONV...DAYTIME HEATING AND STEEP 900-700
MB LAPSE RATES WILL SUPPORT SCT SHSN DURING THE AFTERNOON. ANY LAKE
EFFECT CONTRIBUTION WILL ONLY BE MARGINAL WITH 850 MB TEMPS ONLY TO
AROUND -11C.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 523 AM EST WED MAR 7 2012
MODELS IN GOOD AGREEMENT THAT UPR TROUGH AND COLDER AIR DIGS FM
NORTHERN CANADA THURSDAY INTO THE EASTERN CANADA THURSDAY NIGHT.
THIS PROVIDES GLANCING BLOW OF FAIRLY CHILLY AIR /H85 TEMPS AS LOW
AS -18C/ ACROSS ONTARIO AND THE UPR GREAT LAKES ON THURSDAY NIGHT.
SHORTWAVE/UPR JET IS FCST TO DIG FM THE CANADIAN PRAIRIES INTO THE
BASE OF THE TROUGH THURSDAY NIGHT...BUT MAJORITY OF H85-H7/H7-H5
Q-VECTOR CONVERGENCE WILL ALREADY BE TO THE NORTH AND EAST OF LK
SUPERIOR EARLY THURSDAY EVENING WITH SUBSIDENCE SPREADING ACROSS
UPR MICHIGAN. EVEN WITH THE SUBSIDENCE...DEEP AND COLD TROUGH LEADS
TO MOIST PROFILE AOA H9 THROUGH H6 AND STEEP LAPSE RATES UP TO 8C/KM
WITHIN THAT MOIST LAYER PER GFS/NAM SOUNDINGS NEAR LK SUPERIOR. SNOW
SHOWERS THURSDAY NIGHT WILL PROBABLY BE PRETTY CONVECTIVE/SPLOTCHY
IN COVERAGE. BLYR WINDS ARE STEADILY VEERING FM WNW TO NW THROUGH
THE NIGHT WHICH LIMITS LK EFFECT IN ANY ONE PARTICULAR AREA...THOUGH
SEEMS THAT HIGHER TERRAIN OF WESTERN UPR MI AND AREAS EAST OF
MARQUETTE TO NEWBERRY WOULD STAND TO SEE THE MOST SNOW WITH NW WIND
FCST AT H925/H85.
BY LATE THURSDAY NIGHT...SNOW SHOWERS SHOULD DIMINISH AS THERE IS
CONSENSUS THAT MOISTURE AOA H8 DRIES OUT AND SINCE TEMPS AT
900MB-925MB ARE NOT THAT COOL AT ONLY AROUND -10C. DO SEE SOME
COOLING IN THE H9-H8 LAYER ON FRIDAY AS SECONDARY COLD FRONT SLIDES
ACROSS LK SUPERIOR AND UPR MICHIGAN. FCST SOUNDING AT ERY AT THE END
OF THE FETCH SHOW MOISTENING H95-H8 WITH SOME DRY AIR LINGERING BLO
H95. NOT MUCH SHEAR OR DIRECTIONAL CHANGES IN THE MOIST LAYER SO LK
EFFECT COULD GET BETTER ORGANIZED FOR A TIME IN THE MORNING BEFORE
DAYTIME DRYING AND INCREASING SUBSIDENCE FM ARRIVAL OF SFC RIDGE
LEADS TO DIMINISHING TREND IN THE AFTN. EXPECT ALL LK EFFECT TO
FINISH UP FRIDAY EVENING AS SFC RIDGE AND WARM AIR ADVECTION ARRIVE
IN EARNEST.
IN THE EXTENDED...
WARM AIR ADVECTION ON SATURDAY IS QUITE VIGOROUS AND THERE ARE SOME
PRETTY BEEFY S/SW 1000-850MB WINDS FCST FM GFS/ECMWF IN THE RETURN
FLOW REGIME. IN FACT...H925-H85 WINDS FM BOTH MODELS ARE AOA 45 KTS.
GIVEN THESE LOW-LEVEL WINDS...TIGHTENING PRESSURE GRADIENT BTWN
RIDGE DEPARTING INTO CNTRL GREAT LAKES AND SHARP NORTH-TO-SOUTH
ORIENTED SFC TROUGH PRESSING ACROSS CNTRL CANADA...AND VERY STRONG
PRESSURE FALLS SETTING UP JUST NORTH OF LK SUPERIOR...SATURDAY COULD
BE A BREEZY DAY EVEN WITH THE HIGHER STABILITY DUE TO THE STRONG
WARM AIR ADVECTION/INVERSION. MODELS SEEM TO BE LATCHING ONTO THIS
MORE WINDY TREND. SHOULD SEE HIGHS ON SATURDAY SIMILAR TO THOSE SEEN
YESTERDAY...MAINLY MID-UPR 40S WITH TEMPS STAYING IN THE UPR 30S TO
AROUND 40 DEGREES DOWNWIND OF COOLER LK MICHIGAN WATERS.
MAIN PRECIPITATION CHANCES IN EXTENDED ARE IN THE SUNDAY THROUGH
MONDAY TIME FRAME. AGREEMENT FM THE MODELS REMAINS LOW IN HOW FAR
NORTH UPR LOW CURRENTLY OVER THE DESERT SW WILL BE PROPELLED INTO
GREAT LAKES. ADDED UNCERTAINTY IS LATEST MODEL RUNS REMAIN
CONSISTENT WITH PREVIOUS MODEL RUNS. ECMWF BRINGS UPR LOW INTO UPR
MICHIGAN LATE SUNDAY INTO SUNDAY NIGHT WITH A PERIOD OF RAIN
SHOWERS. GFS KEEPS THE LOW MORE OVR OHIO VALLEY...MISSING CWA WITH
ANY RAINFALL. CANADIAN LOOKS LIKE THE ECMWF BUT IS JUST SLOWER IN
BRINGING THE SYSTEM INTO UPR MICHIGAN. NO REAL TIP OFF TO BUDGE OFF
CONSENSUS AT THIS POINT. SO...HAVE POPS OVER MAINLY SOUTHERN CWA ON
SUNDAY AND MID RANGE CHANCE POPS OVR MOST CWA SUNDAY NIGHT. ONE
TREND THAT IS DEVELOPING IS THE ECMWF SHOWING IT JUST COLD ENOUGH ON
BACKSIDE OF THE SYSTEM BY MONDAY TO HAVE A CHANCE OF SNOW OVR THE
WESTERN CWA. JUST CANNOT GO THIS WAY AT THIS POINT...GIVEN THE LACK
OF AGREEMENT FM THE MODELS IN THE FIRST PLACE. ESSENTIALLY KEPT WHAT
WE HAD GOING WHICH WAS STAYING WARM WITH CHANCE OF RAIN SUNDAY INTO
MONDAY. NO CONFIDENCE AFTER MONDAY AS GFS/ECMWF BECOME COMPLETELY
OUT OF PHASE WITH EACH OTHER. CONSENSUS FCST OF SLIGHT CHANCE POPS
FOR RAIN SHOWERS WITH TEMPS STAYING WARM WORKS FOR NOW UNTIL MORE
SUBSTANTIAL TRENDS CAN BE BETTER IDENTIFIED.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 607 AM EST WED MAR 7 2012
SINCE THE RH OF THE INCOMING AIRMASS REMAINS FAIRLY LO DUE TO THE
ANOMALOUS WARMTH THE ARRIVAL OF LOW CLOUDS AND FOG HAS BEEN DELAYED.
EXPECT AT LEAST AN MVFR CIG/VSBY TO DEVELOP FIRST AT SAW THIS
MORNING BY AROUND 15Z...WITH MORE OF AN UPSLOPE WIND COMPONENT.
DOWNSLOPE NATURE OF S WIND AT IWD/CMX ARGUES AGAINST GOING LOWER
THAN VFR TIL LATE MORNING. STILL EXPECTING SOME LO CLDS TO ARRIVE
AHEAD OF INCOMING COLD FNT BY THIS AFTERNOON WITH HIGHER DEWPOINTS
SURGING INTO THE UPPER GREAT LAKES. BEST SHOT AT IFR/PERHAPS LIFR WL
BE RIGHT BEHIND COLD FROPA AT CMX WITH UPSLOPE WNW WIND...BUT PCPN
INTENSITY LOOKS A BIT LESS IMPRESSIVE WITH BEST FORCING PROGGED TO
PASS TO THE NW. THE ARRIVAL OF COLDER AIR IN THE WAKE OF THE FROPA
WL CHANGE THE PCPN TO SHSN... BUT CONDITIONS SHOULD IMPROVE TO MVFR
GIVEN ONLY MODERATELY COLD INCOMING AIRMASS THAT WILL LIMIT LES
INTENSITY.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 523 AM EST WED MAR 7 2012
GUSTY SW WINDS TO 30 KTS STILL POSSIBLE TODAY OVER EASTERN SECTIONS
AHEAD OF APPROACHING COLD FRONT. ONCE FRONT MOVES THROUGH...MAY SEE
NW WINDS TO 30 KTS INTO THURSDAY OVER MUCH OF THE LAKE. AS COLDER
AIR FLOWS ACROSS LK SUPERIOR THURSDAY NIGHT...INCREASINGLY UNSTABLE
THERMAL PROFILE WITH 30-40 KT WINDS IN MIXED LAYER SUGGEST A GALE
WATCH MAY EVENTUALLY BE NEEDED. MODELS ARE NOT IN AGREEMENT WITH
STRENGTH OF WINDS SO HAVE HELD OFF ON ANY HEADLINE FOR NOW AND JUST
MENTIONED GALE GUSTS. STRONGER WINDS AND HIGH WAVES WITH A BRIEF SHOT
OF COLDER AIR RESULTS IN POTENTIAL FOR HEAVY FREEZING SPRAY OVR CNTRL
AND EASTERN LK SUPERIOR LATER THURSDAY NIGHT. WINDS AND WAVES
DIMINISH LATER FRIDAY WITH ARRIVAL OF HIGH PRESSURE RIDGE BUT THERE
COULD BE ANOTHER STRONGER PERIOD OF SOUTH- SOUTHWEST WINDS LATE
FRIDAY NIGHT THROUGH SATURDAY. IT IS A SITUATION WITH WARM AIR RIDING
OVR THE COOLER LAKE WATERS...BUT STRONG PRESSURE FALLS NORTH OF THE
LAKE AND TIGHT PRESSURE GRADIENT COULD PROVIDE ENOUGH BOOST TO SEE
GALES. WINDS DIMINISH TO LESS THAN 25 KTS BY SUNDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...SRF
SYNOPSIS...JLB
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...JLB
MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
615 AM EST WED MAR 7 2012
.SYNOPSIS...
ISSUED AT 523 AM EST WED MAR 7 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A POSITIVE TILT MID/UPPER
LEVEL TROUGH FROM SASK/MANITOBA TOWARD A CLOSED LOW OVER SRN NEVADA
RESULTING IN SW FLOW FROM THE CNTRL PLAINS TO THE WRN GREAT LAKES.
AT THE SFC...A TROUGH/FRONT EXTENDED FROM NW ONTARIO AND NE MN INTO
ERN NEBRASKA. SOME LIGHT SNOW HAD DEVELOPED BEHIND THE FRONT OVER
ERN ND INTO FAR NW MN. OTHERWISE...NO PCPN WAS OBSERVED ALONG OR
AHEAD OF THE FRONT. VERY MILD AIR HAD SPREAD INTO THE REGION AHEAD
OF THE FRONT ON SSW WINDS WITH TEMPS OVERNIGHT CLIMBING INTO THE 40S
ACROSS MUCH OF WEST AND CENTRAL UPPER MI. BNDRY LAYR MIXING HAS
HELPED KEEP DEWPOINT DEPRESSIONS HIGH ENOUGH TO LIMIT ANY FOG
DEVELOPMENT.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 523 AM EST WED MAR 7 2012
MODELS HAVE CONTINUED WITH TREND TOWARD A LATER ARRIVAL OF THE
FRONT...MOVING INTO IWD AFT 18Z AND TO MQT-IMT BY 00Z. MOISTURE CONV
AND 900-700 MB FGEN ASSOCIATED WITH THE FRONT SHOULD BE ENOUGH TO
SUPPORT DEVELOPMENT AND INCREASING COVERAGE OF LIGHT PCPN BAND
THROUGH WRN UPPER MI IN THE AFTERNOON. PCPN MAY ALSO SPREAD INTO THE
ERN PORTION OF THE CWA WITH 290K-295K ISENTROPIC ASCENT AHEAD OF THE
FRONT. FCST SOUNDINGS SUPPORT LIQUID PCPN OVER MOST OF THE AREA WITH
POTENTIAL FOR CHANGEOVER TO FROZEN PCPN OVER THE FAR WEST LATE. WITH
A SUBSTANTIAL DRY 750-600 MB LAYER AND FREEZING LEVEL ABOVE THE MOIST
LAYER...LACK OF ICE CRYSTALS WOULD LEAD TO LIGHT ACCUMULATIONS OF
MAINLY DRIZZLE. THE NAM/GFS SUGGEST THAT A SHORTWAVE AND STRONGER
850-600 MB FGEN BEHIND THE FRONT WILL REMAIN MAINLY TO THE NW OF THE
CWA...STREAKING THROUGH NW LAKE SUPERIOR.
ENOUGH OF A COLD LAYER MAY DEVELOP BEHIND THE FRONT BY LATE
AFTERNOON WEST AND INTO THE EVENING CENTRAL WITH A SMALL LAYER NEAR
800-750 MB AT OR ABOVE 0C FOR A VERY BRIEF PERIOD OF SOME SLEET.
HOWEVER...ONCE THE DEEPER MOISTURE AND COLD AIR ARRIVE FROM WEST TO
EAST...THE PRECIP TYPE SHOULD CHANGE OVER FROM DZ/PL TO SNOW. WITH
ONLY A BRIEF PERIOD FOR ANY SNOW POSSIBLE...ANY ACCUMULATIONS SHOULD
AMOUNT TO LESS THAN A HALF INCH. LAKE ENHANCED SNOW POTENTIAL OVER
THE WEST WITH NW FLOW BEHIND THE FRONT WILL BE LIMITED BY THE
MARGINAL INSTABILITY AND QUICK ARRIVAL OF DRIER AIR AND LOW INVERSIO
HEIGHTS NEAR 3K FT.
THURSDAY...AS THE MID LEVEL TROUGH SLIDES INTO THE AREA MODERATE TO
STRONG 850-500 MB QVECTOR CONV...DAYTIME HEATING AND STEEP 900-700
MB LAPSE RATES WILL SUPPORT SCT SHSN DURING THE AFTERNOON. ANY LAKE
EFFECT CONTRIBUTION WILL ONLY BE MARGINAL WITH 850 MB TEMPS ONLY TO
AROUND -11C.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 523 AM EST WED MAR 7 2012
MODELS IN GOOD AGREEMENT THAT UPR TROUGH AND COLDER AIR DIGS FM
NORTHERN CANADA THURSDAY INTO THE EASTERN CANADA THURSDAY NIGHT.
THIS PROVIDES GLANCING BLOW OF FAIRLY CHILLY AIR /H85 TEMPS AS LOW
AS -18C/ ACROSS ONTARIO AND THE UPR GREAT LAKES ON THURSDAY NIGHT.
SHORTWAVE/UPR JET IS FCST TO DIG FM THE CANADIAN PRAIRIES INTO THE
BASE OF THE TROUGH THURSDAY NIGHT...BUT MAJORITY OF H85-H7/H7-H5
Q-VECTOR CONVERGENCE WILL ALREADY BE TO THE NORTH AND EAST OF LK
SUPERIOR EARLY THURSDAY EVENING WITH SUBSIDENCE SPREADING ACROSS
UPR MICHIGAN. EVEN WITH THE SUBSIDENCE...DEEP AND COLD TROUGH LEADS
TO MOIST PROFILE AOA H9 THROUGH H6 AND STEEP LAPSE RATES UP TO 8C/KM
WITHIN THAT MOIST LAYER PER GFS/NAM SOUNDINGS NEAR LK SUPERIOR. SNOW
SHOWERS THURSDAY NIGHT WILL PROBABLY BE PRETTY CONVECTIVE/SPLOTCHY
IN COVERAGE. BLYR WINDS ARE STEADILY VEERING FM WNW TO NW THROUGH
THE NIGHT WHICH LIMITS LK EFFECT IN ANY ONE PARTICULAR AREA...THOUGH
SEEMS THAT HIGHER TERRAIN OF WESTERN UPR MI AND AREAS EAST OF
MARQUETTE TO NEWBERRY WOULD STAND TO SEE THE MOST SNOW WITH NW WIND
FCST AT H925/H85.
BY LATE THURSDAY NIGHT...SNOW SHOWERS SHOULD DIMINISH AS THERE IS
CONSENSUS THAT MOISTURE AOA H8 DRIES OUT AND SINCE TEMPS AT
900MB-925MB ARE NOT THAT COOL AT ONLY AROUND -10C. DO SEE SOME
COOLING IN THE H9-H8 LAYER ON FRIDAY AS SECONDARY COLD FRONT SLIDES
ACROSS LK SUPERIOR AND UPR MICHIGAN. FCST SOUNDING AT ERY AT THE END
OF THE FETCH SHOW MOISTENING H95-H8 WITH SOME DRY AIR LINGERING BLO
H95. NOT MUCH SHEAR OR DIRECTIONAL CHANGES IN THE MOIST LAYER SO LK
EFFECT COULD GET BETTER ORGANIZED FOR A TIME IN THE MORNING BEFORE
DAYTIME DRYING AND INCREASING SUBSIDENCE FM ARRIVAL OF SFC RIDGE
LEADS TO DIMINISHING TREND IN THE AFTN. EXPECT ALL LK EFFECT TO
FINISH UP FRIDAY EVENING AS SFC RIDGE AND WARM AIR ADVECTION ARRIVE
IN EARNEST.
IN THE EXTENDED...
WARM AIR ADVECTION ON SATURDAY IS QUITE VIGOROUS AND THERE ARE SOME
PRETTY BEEFY S/SW 1000-850MB WINDS FCST FM GFS/ECMWF IN THE RETURN
FLOW REGIME. IN FACT...H925-H85 WINDS FM BOTH MODELS ARE AOA 45 KTS.
GIVEN THESE LOW-LEVEL WINDS...TIGHTENING PRESSURE GRADIENT BTWN
RIDGE DEPARTING INTO CNTRL GREAT LAKES AND SHARP NORTH-TO-SOUTH
ORIENTED SFC TROUGH PRESSING ACROSS CNTRL CANADA...AND VERY STRONG
PRESSURE FALLS SETTING UP JUST NORTH OF LK SUPERIOR...SATURDAY COULD
BE A BREEZY DAY EVEN WITH THE HIGHER STABILITY DUE TO THE STRONG
WARM AIR ADVECTION/INVERSION. MODELS SEEM TO BE LATCHING ONTO THIS
MORE WINDY TREND. SHOULD SEE HIGHS ON SATURDAY SIMILAR TO THOSE SEEN
YESTERDAY...MAINLY MID-UPR 40S WITH TEMPS STAYING IN THE UPR 30S TO
AROUND 40 DEGREES DOWNWIND OF COOLER LK MICHIGAN WATERS.
MAIN PRECIPITATION CHANCES IN EXTENDED ARE IN THE SUNDAY THROUGH
MONDAY TIME FRAME. AGREEMENT FM THE MODELS REMAINS LOW IN HOW FAR
NORTH UPR LOW CURRENTLY OVER THE DESERT SW WILL BE PROPELLED INTO
GREAT LAKES. ADDED UNCERTAINTY IS LATEST MODEL RUNS REMAIN
CONSISTENT WITH PREVIOUS MODEL RUNS. ECMWF BRINGS UPR LOW INTO UPR
MICHIGAN LATE SUNDAY INTO SUNDAY NIGHT WITH A PERIOD OF RAIN
SHOWERS. GFS KEEPS THE LOW MORE OVR OHIO VALLEY...MISSING CWA WITH
ANY RAINFALL. CANADIAN LOOKS LIKE THE ECMWF BUT IS JUST SLOWER IN
BRINGING THE SYSTEM INTO UPR MICHIGAN. NO REAL TIP OFF TO BUDGE OFF
CONSENSUS AT THIS POINT. SO...HAVE POPS OVER MAINLY SOUTHERN CWA ON
SUNDAY AND MID RANGE CHANCE POPS OVR MOST CWA SUNDAY NIGHT. ONE
TREND THAT IS DEVELOPING IS THE ECMWF SHOWING IT JUST COLD ENOUGH ON
BACKSIDE OF THE SYSTEM BY MONDAY TO HAVE A CHANCE OF SNOW OVR THE
WESTERN CWA. JUST CANNOT GO THIS WAY AT THIS POINT...GIVEN THE LACK
OF AGREEMENT FM THE MODELS IN THE FIRST PLACE. ESSENTIALLY KEPT WHAT
WE HAD GOING WHICH WAS STAYING WARM WITH CHANCE OF RAIN SUNDAY INTO
MONDAY. NO CONFIDENCE AFTER MONDAY AS GFS/ECMWF BECOME COMPLETELY
OUT OF PHASE WITH EACH OTHER. CONSENSUS FCST OF SLIGHT CHANCE POPS
FOR RAIN SHOWERS WITH TEMPS STAYING WARM WORKS FOR NOW UNTIL MORE
SUBSTANTIAL TRENDS CAN BE BETTER IDENTIFIED.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 607 AM EST WED MAR 7 2012
SINCE THE RH OF THE INCOMING AIRMASS REMAINS FAIRLY LO DUE TO THE
ANOMALOUS WARMTH THE ARRIVAL OF LOW CLOUDS AND FOG HAS BEEN DELAYED.
EXPECT AT LEAST AN MVFR CIG/VSBY TO DEVELOP FIRST AT SAW THIS
MORNING BY AROUND 15Z...WITH MORE OF AN UPSLOPE WIND COMPONENT.
DOWNSLOPE NATURE OF S WIND AT IWD/CMX ARGUES AGAINST GOING LOWER
THAN VFR TIL LATE MORNING. STILL EXPECTING SOME LO CLDS TO ARRIVE
AHEAD OF INCOMING COLD FNT BY THIS AFTERNOON WITH HIGHER DEWPOINTS
SURGING INTO THE UPPER GREAT LAKES. BEST SHOT AT IFR/PERHAPS LIFR WL
BE RIGHT BEHIND COLD FROPA AT CMX WITH UPSLOPE WNW WIND...BUT PCPN
INTENSITY LOOKS A BIT LESS IMPRESSIVE WITH BEST FORCING PROGGED TO
PASS TO THE NW. THE ARRIVAL OF COLDER AIR IN THE WAKE OF THE FROPA
WL CHANGE THE PCPN TO SHSN... BUT CONDITIONS SHOULD IMPROVE TO MVFR
GIVEN ONLY MODERATELY COLD INCOMING AIRMASS THAT WILL LIMIT LES
INTENSITY.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 523 AM EST WED MAR 7 2012
GUSTY SW WINDS TO 30 KTS STILL POSSIBLE TODAY OVER EASTERN SECTIONS
AHEAD OF APPROACHING COLD FRONT. ONCE FRONT MOVES THROUGH...MAY SEE
NW WINDS TO 30 KTS INTO THURSDAY OVER MUCH OF THE LAKE. AS COLDER
AIR FLOWS ACROSS LK SUPERIOR THURSDAY NIGHT...INCREASINGLY UNSTABLE
THERMAL PROFILE WITH 30-40 KT WINDS IN MIXED LAYER SUGGEST A GALE
WATCH MAY EVENTUALLY BE NEEDED. MODELS ARE NOT IN AGREEMENT WITH
STRENGTH OF WINDS SO HAVE HELD OFF ON ANY HEADLINE FOR NOW AND JUST
MENTIONED GALE GUSTS. STRONGER WINDS AND HIGH WAVES WITH A BRIEF SHOT
OF COLDER AIR RESULTS IN POTENTIAL FOR HEAVY FREEZING SPRAY OVR CNTRL
AND EASTERN LK SUPERIOR LATER THURSDAY NIGHT. WINDS AND WAVES
DIMINISH LATER FRIDAY WITH ARRIVAL OF HIGH PRESSURE RIDGE BUT THERE
COULD BE ANOTHER STRONGER PERIOD OF SOUTH- SOUTHWEST WINDS LATE
FRIDAY NIGHT THROUGH SATURDAY. IT IS A SITUATION WITH WARM AIR RIDING
OVR THE COOLER LAKE WATERS...BUT STRONG PRESSURE FALLS NORTH OF THE
LAKE AND TIGHT PRESSURE GRADIENT COULD PROVIDE ENOUGH BOOST TO SEE
GALES. WINDS DIMINISH TO LESS THAN 25 KTS BY SUNDAY. &&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...JLB
MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
528 AM EST WED MAR 7 2012
.SYNOPSIS...
ISSUED AT 523 AM EST WED MAR 7 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A POSITIVE TILT MID/UPPER
LEVEL TROUGH FROM SASK/MANITOBA TOWARD A CLOSED LOW OVER SRN NEVADA
RESULTING IN SW FLOW FROM THE CNTRL PLAINS TO THE WRN GREAT LAKES.
AT THE SFC...A TROUGH/FRONT EXTENDED FROM NW ONTARIO AND NE MN INTO
ERN NEBRASKA. SOME LIGHT SNOW HAD DEVELOPED BEHIND THE FRONT OVER
ERN ND INTO FAR NW MN. OTHERWISE...NO PCPN WAS OBSERVED ALONG OR
AHEAD OF THE FRONT. VERY MILD AIR HAD SPREAD INTO THE REGION AHEAD
OF THE FRONT ON SSW WINDS WITH TEMPS OVERNIGHT CLIMBING INTO THE 40S
ACROSS MUCH OF WEST AND CENTRAL UPPER MI. BNDRY LAYR MIXING HAS
HELPED KEEP DEWPOINT DEPRESSIONS HIGH ENOUGH TO LIMIT ANY FOG
DEVELOPMENT.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 523 AM EST WED MAR 7 2012
MODELS HAVE CONTINUED WITH TREND TOWARD A LATER ARRIVAL OF THE
FRONT...MOVING INTO IWD AFT 18Z AND TO MQT-IMT BY 00Z. MOISTURE CONV
AND 900-700 MB FGEN ASSOCIATED WITH THE FRONT SHOULD BE ENOUGH TO
SUPPORT DEVELOPMENT AND INCREASING COVERAGE OF LIGHT PCPN BAND
THROUGH WRN UPPER MI IN THE AFTERNOON. PCPN MAY ALSO SPREAD INTO THE
ERN PORTION OF THE CWA WITH 290K-295K ISENTROPIC ASCENT AHEAD OF THE
FRONT. FCST SOUNDINGS SUPPORT LIQUID PCPN OVER MOST OF THE AREA WITH
POTENTIAL FOR CHANGEOVER TO FROZEN PCPN OVER THE FAR WEST LATE. WITH
A SUBSTANTIAL DRY 750-600 MB LAYER AND FREEZING LEVEL ABOVE THE MOIST
LAYER...LACK OF ICE CRYSTALS WOULD LEAD TO LIGHT ACCUMULATIONS OF
MAINLY DRIZZLE. THE NAM/GFS SUGGEST THAT A SHORTWAVE AND STRONGER
850-600 MB FGEN BEHIND THE FRONT WILL REMAIN MAINLY TO THE NW OF THE
CWA...STREAKING THROUGH NW LAKE SUPERIOR.
ENOUGH OF A COLD LAYER MAY DEVELOP BEHIND THE FRONT BY LATE
AFTERNOON WEST AND INTO THE EVENING CENTRAL WITH A SMALL LAYER NEAR
800-750 MB AT OR ABOVE 0C FOR A VERY BRIEF PERIOD OF SOME SLEET.
HOWEVER...ONCE THE DEEPER MOISTURE AND COLD AIR ARRIVE FROM WEST TO
EAST...THE PRECIP TYPE SHOULD CHANGE OVER FROM DZ/PL TO SNOW. WITH
ONLY A BRIEF PERIOD FOR ANY SNOW POSSIBLE...ANY ACCUMULATIONS SHOULD
AMOUNT TO LESS THAN A HALF INCH. LAKE ENHANCED SNOW POTENTIAL OVER
THE WEST WITH NW FLOW BEHIND THE FRONT WILL BE LIMITED BY THE
MARGINAL INSTABILITY AND QUICK ARRIVAL OF DRIER AIR AND LOW INVERSIO
HEIGHTS NEAR 3K FT.
THURSDAY...AS THE MID LEVEL TROUGH SLIDES INTO THE AREA MODERATE TO
STRONG 850-500 MB QVECTOR CONV...DAYTIME HEATING AND STEEP 900-700
MB LAPSE RATES WILL SUPPORT SCT SHSN DURING THE AFTERNOON. ANY LAKE
EFFECT CONTRIBUTION WILL ONLY BE MARGINAL WITH 850 MB TEMPS ONLY TO
AROUND -11C.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 523 AM EST WED MAR 7 2012
MODELS IN GOOD AGREEMENT THAT UPR TROUGH AND COLDER AIR DIGS FM
NORTHERN CANADA THURSDAY INTO THE EASTERN CANADA THURSDAY NIGHT.
THIS PROVIDES GLANCING BLOW OF FAIRLY CHILLY AIR /H85 TEMPS AS LOW
AS -18C/ ACROSS ONTARIO AND THE UPR GREAT LAKES ON THURSDAY NIGHT.
SHORTWAVE/UPR JET IS FCST TO DIG FM THE CANADIAN PRAIRIES INTO THE
BASE OF THE TROUGH THURSDAY NIGHT...BUT MAJORITY OF H85-H7/H7-H5
Q-VECTOR CONVERGENCE WILL ALREADY BE TO THE NORTH AND EAST OF LK
SUPERIOR EARLY THURSDAY EVENING WITH SUBSIDENCE SPREADING ACROSS
UPR MICHIGAN. EVEN WITH THE SUBSIDENCE...DEEP AND COLD TROUGH LEADS
TO MOIST PROFILE AOA H9 THROUGH H6 AND STEEP LAPSE RATES UP TO 8C/KM
WITHIN THAT MOIST LAYER PER GFS/NAM SOUNDINGS NEAR LK SUPERIOR. SNOW
SHOWERS THURSDAY NIGHT WILL PROBABLY BE PRETTY CONVECTIVE/SPLOTCHY
IN COVERAGE. BLYR WINDS ARE STEADILY VEERING FM WNW TO NW THROUGH
THE NIGHT WHICH LIMITS LK EFFECT IN ANY ONE PARTICULAR AREA...THOUGH
SEEMS THAT HIGHER TERRAIN OF WESTERN UPR MI AND AREAS EAST OF
MARQUETTE TO NEWBERRY WOULD STAND TO SEE THE MOST SNOW WITH NW WIND
FCST AT H925/H85.
BY LATE THURSDAY NIGHT...SNOW SHOWERS SHOULD DIMINISH AS THERE IS
CONSENSUS THAT MOISTURE AOA H8 DRIES OUT AND SINCE TEMPS AT
900MB-925MB ARE NOT THAT COOL AT ONLY AROUND -10C. DO SEE SOME
COOLING IN THE H9-H8 LAYER ON FRIDAY AS SECONDARY COLD FRONT SLIDES
ACROSS LK SUPERIOR AND UPR MICHIGAN. FCST SOUNDING AT ERY AT THE END
OF THE FETCH SHOW MOISTENING H95-H8 WITH SOME DRY AIR LINGERING BLO
H95. NOT MUCH SHEAR OR DIRECTIONAL CHANGES IN THE MOIST LAYER SO LK
EFFECT COULD GET BETTER ORGANIZED FOR A TIME IN THE MORNING BEFORE
DAYTIME DRYING AND INCREASING SUBSIDENCE FM ARRIVAL OF SFC RIDGE
LEADS TO DIMINISHING TREND IN THE AFTN. EXPECT ALL LK EFFECT TO
FINISH UP FRIDAY EVENING AS SFC RIDGE AND WARM AIR ADVECTION ARRIVE
IN EARNEST.
IN THE EXTENDED...
WARM AIR ADVECTION ON SATURDAY IS QUITE VIGOROUS AND THERE ARE SOME
PRETTY BEEFY S/SW 1000-850MB WINDS FCST FM GFS/ECMWF IN THE RETURN
FLOW REGIME. IN FACT...H925-H85 WINDS FM BOTH MODELS ARE AOA 45 KTS.
GIVEN THESE LOW-LEVEL WINDS...TIGHTENING PRESSURE GRADIENT BTWN
RIDGE DEPARTING INTO CNTRL GREAT LAKES AND SHARP NORTH-TO-SOUTH
ORIENTED SFC TROUGH PRESSING ACROSS CNTRL CANADA...AND VERY STRONG
PRESSURE FALLS SETTING UP JUST NORTH OF LK SUPERIOR...SATURDAY COULD
BE A BREEZY DAY EVEN WITH THE HIGHER STABILITY DUE TO THE STRONG
WARM AIR ADVECTION/INVERSION. MODELS SEEM TO BE LATCHING ONTO THIS
MORE WINDY TREND. SHOULD SEE HIGHS ON SATURDAY SIMILAR TO THOSE SEEN
YESTERDAY...MAINLY MID-UPR 40S WITH TEMPS STAYING IN THE UPR 30S TO
AROUND 40 DEGREES DOWNWIND OF COOLER LK MICHIGAN WATERS.
MAIN PRECIPITATION CHANCES IN EXTENDED ARE IN THE SUNDAY THROUGH
MONDAY TIME FRAME. AGREEMENT FM THE MODELS REMAINS LOW IN HOW FAR
NORTH UPR LOW CURRENTLY OVER THE DESERT SW WILL BE PROPELLED INTO
GREAT LAKES. ADDED UNCERTAINTY IS LATEST MODEL RUNS REMAIN
CONSISTENT WITH PREVIOUS MODEL RUNS. ECMWF BRINGS UPR LOW INTO UPR
MICHIGAN LATE SUNDAY INTO SUNDAY NIGHT WITH A PERIOD OF RAIN
SHOWERS. GFS KEEPS THE LOW MORE OVR OHIO VALLEY...MISSING CWA WITH
ANY RAINFALL. CANADIAN LOOKS LIKE THE ECMWF BUT IS JUST SLOWER IN
BRINGING THE SYSTEM INTO UPR MICHIGAN. NO REAL TIP OFF TO BUDGE OFF
CONSENSUS AT THIS POINT. SO...HAVE POPS OVER MAINLY SOUTHERN CWA ON
SUNDAY AND MID RANGE CHANCE POPS OVR MOST CWA SUNDAY NIGHT. ONE
TREND THAT IS DEVELOPING IS THE ECMWF SHOWING IT JUST COLD ENOUGH ON
BACKSIDE OF THE SYSTEM BY MONDAY TO HAVE A CHANCE OF SNOW OVR THE
WESTERN CWA. JUST CANNOT GO THIS WAY AT THIS POINT...GIVEN THE LACK
OF AGREEMENT FM THE MODELS IN THE FIRST PLACE. ESSENTIALLY KEPT WHAT
WE HAD GOING WHICH WAS STAYING WARM WITH CHANCE OF RAIN SUNDAY INTO
MONDAY. NO CONFIDENCE AFTER MONDAY AS GFS/ECMWF BECOME COMPLETELY
OUT OF PHASE WITH EACH OTHER. CONSENSUS FCST OF SLIGHT CHANCE POPS
FOR RAIN SHOWERS WITH TEMPS STAYING WARM WORKS FOR NOW UNTIL MORE
SUBSTANTIAL TRENDS CAN BE BETTER IDENTIFIED.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING)
ISSUED AT 523 AM EST WED MAR 7 2012
SINCE THE RH OF THE INCOMING AIRMASS REMAINS FAIRLY LO DUE TO THE
ANOMALOUS WARMTH...DELAYED THE ARRIVAL OF LO CLDS/FOG AT ALL 3
SITES. SAW STILL LOOKS TO HAVE THE BEST SHOT AT SEEING AT LEAST AN
MVFR CIG/VSBY BY 12Z WITH MORE OF AN UPSLOPE WIND COMPONENT...BUT
DOWNSLOPE NATURE OF S WIND AT IWD/CMX ARGUES AGAINST GOING LOWER
THAN VFR THRU SUNRISE. SINCE THE PRES GRADIENT HAS WEAKENED OVER
CMX...REMOVED LLWS FROM THE TAF FOR THAT LOCATION. STILL EXPECTING
SOME LO CLDS TO ARRIVE AHEAD OF INCOMING COLD FNT BY THIS AFTN WITH
HIER DEWPTS SURGING INTO THE UPR LKS...BUT TRENDED BACK A BIT FM THE
PREVIOUS FCST OF IFR EXCEPT AT SAW GIVEN MORE FAVORABLE UPSLOPE S
WIND. BEST SHOT AT IFR/PERHAPS LIFR WL BE RIGHT BEHIND COLD FROPA AT
CMX WITH UPSLOPE WNW WIND...BUT PCPN INTENSITY LOOKS A BIT LESS
IMPRESSIVE WITH BEST FORCING PROGGED TO PASS TO THE NW. THE ARRIVAL
OF COLDER AIR IN THE WAKE OF THE FROPA WL CHANGE THE PCPN TO SHSN...
BUT CONDITIONS SHOULD IMPROVE TO MVFR GIVEN MODERATE CHILL OF THE
INCOMING AIRMASS THAT WL LIMIT LES INTENSITY.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 523 AM EST WED MAR 7 2012
NW WINDS OF 20-30 KTS EXPECTED THURSDAY NIGHT AS COLDER AIR FLOWS
ACROSS LK SUPERIOR. INCREASINGLY UNSTABLE THERMAL PROFILE WITH 30-40
KT WINDS IN MIXED LAYER SUGGEST THE EVENTUALLY NEED FOR A GALE
WATCH. MODELS ARE NOT IN AGREEMENT WITH STRENGTH OF WINDS SO HAVE
HELD OFF ON ANY HEADLINE FOR NOW. STRONGER WINDS AND HIGH WAVES WITH
A BRIEF SHOT OF COLDER AIR RESULTS IN POTENTIAL FOR HEAVY FREEZING
SPRAY OVR CNTRL AND EASTERN LK SUPERIOR LATER THURSDAY NIGHT. WINDS
AND WAVES DIMINISH LATER FRIDAY WITH ARRIVAL OF HIGH PRESSURE RIDGE
BUT THERE COULD BE ANOTHER STRONGER PERIOD OF SOUTH-SOUTHWEST WINDS
LATE FRIDAY NIGHT THROUGH SATURDAY. IT IS A SITUATION WITH WARM AIR
RIDING OVR THE COOLER LAKE WATERS...BUT STRONG PRESSURE FALLS NORTH
OF THE LAKE AND TIGHT PRESSURE GRADIENT COULD PROVIDE ENOUGH BOOST
TO SEE GALES. WINDS DIMINISH TO LESS THAN 25 KTS BY SUNDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...KC
MARINE...JLA
AREA FORECAST DISCUSSION
NWS HASTINGS NE
549 AM CST WED MAR 7 2012
.AVIATION...12Z KGRI TAF. WIND SPEEDS ARE A CONCERN BEHIND THE
DEPARTING COLD FRONT PUSHING TO THE SOUTHEAST. IMPRESSIVE HEIGHT
RISES ARE CREATING SOME GOOD WIND GUSTS THIS MORNING WITH A DECK
OF STRATUS SOON TO FOLLOW THIS MORNING. WIND SHOULD CONTINUE TO
BE GUSTY BEHIND THE FRONT AS LOW-LEVEL LAPSE RATES PROMOTE
EFFICIENT MOMENTUM TRANSFER. KEPT CEILINGS FROM DIPPING DOWN TO
IFR...AND KEPT THEM AT MVFR CONSIDERING MOST OBSERVATIONS
UPSTREAM. WIND SHOULD SUBSIDE THIS EVENING WITH RELAXING PRESSURE
GRADIENTS AND REDUCED MIXING.
&&
.PREV DISCUSSION... /ISSUED 424 AM CST WED MAR 7 2012/
SHORT TERM...TODAY THROUGH FRIDAY NIGHT.
UPPER AIR ANALYSIS INDICATES A DEEP UPPER LEVEL TROUGH AXIS
MOVING ONTO THE WEST COAST WHILE THE EASTERN HALF OF THE UNITED
STATES REMAINS UNDER A WEAK AMPLITUDE RIDGE IN MOSTLY ZONAL FLOW.
AT 500 MB...THE RIDGE AXIS REMAINS SITUATED ALONG THE EAST COAST
WITH A TROUGH AXIS ALONG THE WEST COAST. AT THE SURFACE...HIGH
PRESSURE REMAINS OFF THE EAST COAST WHILE LOW PRESSURE HAS
DEVELOPED ACROSS THE NEVADA/ARIZONA STATE LINE. LOOKING AT WATER
VAPOR IMAGERY...THIS LOW PRESSURE SYSTEM HAS KICKED UP QUITE A
MOISTURE/CLOUD FIELD ACROSS THE HIGH PLAINS AND WESTERN CENTRAL
PLAINS.
MODELS STILL INDICATE A CLOSED UPPER LEVEL LOW ACROSS NEVADA HELPING
PUSH A STRONG COLD FRONT THROUGH THE PLAINS. THE FRONT IS STILL
PEGGED TO MOVE THROUGH THE REGION THIS MORNING. LATEST MOSAIC RADAR
IMAGERY AND METARS SHOW THE FRONT HAS MADE IT TO NORTHWEST PORTION
OF THE CWA BY 10Z. WINDS BEHIND THE FRONT WERE ALREADY NEAR 25 KNOTS
WITH GUSTS AROUND 30 KTS.
MODEL SOLUTIONS ARE TRENDING TOWARDS INCREASED WIND SPEEDS BEHIND
THE FRONT. THE NAM SOLUTION SHOWS 3 HOUR HEIGHT RISES TO NEAR 9MB AT
12Z AND THE HRRR MODELS ALSO SUGGESTS HIGHER WIND SPEEDS ACROSS THE
NORTHWEST WITH WIND GUSTS NEAR 35 KTS. DECIDED TO INCREASE WINDS ON
THE BACKSIDE OF THE FRONT. HOWEVER...WHILE WINDS WILL BE BREEZY
DURING THE MORNING HOURS...EXPECT ANY WINDS THAT REACH WIND ADVISORY CRITERIA
TO BE SHORT LIVED.
REGARDING POPS WEDNESDAY THROUGH THURSDAY...BOTH THE GFS AND THE EC
KEEP SLIGHT POPS ACROSS THE EAST WITH THE FRONTAL PASSAGE DURING THE
DAY. BY WEDNESDAY NIGHT...BOTH MODELS PUSH THE SURFACE LOW FARTHER
SOUTH...THUS MOVING POPS FARTHER SOUTH. HOWEVER...THE 0Z WRF TRIES
TO FIRE OFF SOME SHOWERS ACROSS THE KANSAS COUNTIES ROUGHLY 3Z TO 7Z
ALONG THE ELEVATED FRONT. FOR NOW..DECIDED TO GO WITH SLIGHT TO
CHANCE POPS ACROSS THE SOUTHERN KANSAS COUNTIES. AS FOR PRECIP
TYPE...MODEL SOUNDINGS IN THIS AREA STILL SHOW A GOOD DRY LAYER AT
THE SURFACE SUGGESTING POSSIBLE DRIZZLE IF ANYTHING AT ALL. WHILE
FREEZING DRIZZLE MIGHT BE POSSIBLE...SURFACE TEMPERATURES SHOULD
REMAIN NEAR OR ABOVE FREEZING THROUGH 7Z.
THE TROUGH AXIS CONTINUES TO PUSH EAST BY THURSDAY WITH THE CLOSED
LOW REMAINING OVER THE SOUTHWEST THROUGH THE PERIOD. RIDGING BEGINS
TO BUILD IN ACROSS THE WEST...AND REMAINS THROUGH THE REST OF THE
PERIOD. HIGH TEMPERATURES ARE EXPECTED TO BE IN THE LOW TO MID 50S
WITH LOWS IN THE UPPER 20S TO MID 30S. POPS REMAIN SOUTH OF THE
CWA BEGINNING 12Z THURSDAY.
LONG TERM...SATURDAY THROUGH TUESDAY.
WE WILL KICK OFF THE LONG TERM WITH RATHER DISPARATE SOLUTIONS
BETWEEN MODELS. MODELS ARE GENERALLY INDICATING THAT AT 12Z
SATURDAY...A CLOSED LOW WILL BE LOCATED SOMEWHERE BETWEEN THE
SOUTHERN ROCKIES AND SOUTHWESTERN KANSAS...EXCEPT FOR THE CANADIAN
MODEL...WHICH PREDICTS A CLOSED LOW IN NORTHWESTERN MEXICO...NOT FAR
FROM WHERE THE GFS40 ADVERTISES A SECOND CLOSED LOW...WITH ITS
NORTHERN PREVIOUSLY MENTIONED CLOSED LOW BEING THE EASTERN OUTLIER
IN SOUTHWESTERN KANSAS ALONG WITH DGEX. THIS EASTERN TENDENCY HAS
HELD TRUE TO THE GFS FOR SOME TIME...ALTHOUGH SOLUTIONS ARE NOT
QUITE SO DISPARATE WITH THIS CLOSED LOW AS IT TRACKS
NORTHEAST...WHICH IS A PROMISING SIGN WHEN CONSIDERING THE LARGE
DISAGREEMENT AMONG THE LONG RANGE SOLUTIONS IN THE RECENT PAST.
CONSOLIDATING THE PROJECTED MODEL SOLUTIONS IS PREFERABLE OVER THE
WEEKEND...WITH THE AXIS OF THE LOW/TROUGH EXITING BY SUNDAY NIGHT.
TEMPERATURES SHOULD BE SEASONABLE FOR THE WEEKEND AND ABOVE NORMAL
INTO THE NEXT WORK WEEK WITHIN SOUTHWEST FLOW ALOFT. THE SECONDARY
CLOSED LOW OVER NORTHWESTERN MEXICO SHOULD HEAD EAST INTO TEXAS
AND BE TOO FAR SOUTH TO AFFECT US. AN AREA OF ISENTROPIC LIFT WILL
SPREAD NORTH IN ADVANCE OF THE APPROACHING LOW/TROUGH AND
CONTINUED WITH VERY LOW CHANCES OF PRECIPITATION GENERALLY
SATURDAY THROUGH SUNDAY. AGAIN...AFTER THE TROUGH PASSES...DRY AND
WARM WEATHER WILL PREVAIL FOR THE BEGINNING OF THE WORK WEEK.
PREV DISCUSSION... /ISSUED 117 AM CST WED MAR 7 2012/
AVIATION...06Z KGRI TAF. WIND SPEEDS AND DIRECTION ARE A CONCERN
WITH THE APPROACHING COLD FRONT FROM THE NORTHWEST. SHORTLY AFTER
THE COLD FRONT PASSES EARLY THIS MORNING...WIND DIRECTION SHOULD
SHIFT TO THE NORTH WITH NOTICEABLE GUSTS...CONSIDERING THE
IMPRESSIVE HEIGHT RISES. A DECK OF STRATUS SHOULD SOON FOLLOW WITHIN A
COUPLE OF HOURS OF FRONT PASSAGE. JUDGING BY THE LATEST
INTERPOLATION TOOLS...I MAY BE TOO SLOW WITH FRONT PASSAGE...SO
MAY NEED TO UPDATE SO THAT THE COLD FRONT PASSAGE WILL BE CLOSER
TO 10Z TO 11Z. WIND SHOULD CONTINUE TO BE GUST BEHIND THE FRONT AS
LOW-LEVEL LAPSE RATES PROMOTE EFFICIENT MOMENTUM TRANSFER. KEPT
CEILINGS FROM DIPPING DOWN TO IFR...AND KEPT THEM AT MVFR
CONSIDERING MOST OBSERVATIONS UPSTREAM.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHOR TERM...BDS
LONG TERM/AVIATION...HEINLEIN
AREA FORECAST DISCUSSION
NWS HASTINGS NE
424 AM CST WED MAR 7 2012
.SHORT TERM...TODAY THROUGH FRIDAY NIGHT.
UPPER AIR ANALYSIS INDICATES A DEEP UPPER LEVEL TROUGH AXIS
MOVING ONTO THE WEST COAST WHILE THE EASTERN HALF OF THE UNITED
STATES REMAINS UNDER A WEAK AMPLITUDE RIDGE IN MOSTLY ZONAL FLOW.
AT 500 MB...THE RIDGE AXIS REMAINS SITUATED ALONG THE EAST COAST
WITH A TROUGH AXIS ALONG THE WEST COAST. AT THE SURFACE...HIGH
PRESSURE REMAINS OFF THE EAST COAST WHILE LOW PRESSURE HAS
DEVELOPED ACROSS THE NEVADA/ARIZONA STATE LINE. LOOKING AT WATER
VAPOR IMAGERY...THIS LOW PRESSURE SYSTEM HAS KICKED UP QUITE A
MOISTURE/CLOUD FIELD ACROSS THE HIGH PLAINS AND WESTERN CENTRAL
PLAINS.
MODELS STILL INDICATE A CLOSED UPPER LEVEL LOW ACROSS NEVADA HELPING
PUSH A STRONG COLD FRONT THROUGH THE PLAINS. THE FRONT IS STILL
PEGGED TO MOVE THROUGH THE REGION THIS MORNING. LATEST MOSAIC RADAR
IMAGERY AND METARS SHOW THE FRONT HAS MADE IT TO NORTHWEST PORTION
OF THE CWA BY 10Z. WINDS BEHIND THE FRONT WERE ALREADY NEAR 25 KNOTS
WITH GUSTS AROUND 30 KTS.
MODEL SOLUTIONS ARE TRENDING TOWARDS INCREASED WIND SPEEDS BEHIND
THE FRONT. THE NAM SOLUTION SHOWS 3 HOUR HEIGHT RISES TO NEAR 9MB AT
12Z AND THE HRRR MODELS ALSO SUGGESTS HIGHER WIND SPEEDS ACROSS THE
NORTHWEST WITH WIND GUSTS NEAR 35 KTS. DECIDED TO INCREASE WINDS ON
THE BACKSIDE OF THE FRONT. HOWEVER...WHILE WINDS WILL BE BREEZY
DURING THE MORNING HOURS...EXPECT ANY WINDS THAT REACH WIND ADVISORY CRITERIA
TO BE SHORT LIVED.
REGARDING POPS WEDNESDAY THROUGH THURSDAY...BOTH THE GFS AND THE EC
KEEP SLIGHT POPS ACROSS THE EAST WITH THE FRONTAL PASSAGE DURING THE
DAY. BY WEDNESDAY NIGHT...BOTH MODELS PUSH THE SURFACE LOW FARTHER
SOUTH...THUS MOVING POPS FARTHER SOUTH. HOWEVER...THE 0Z WRF TRIES
TO FIRE OFF SOME SHOWERS ACROSS THE KANSAS COUNTIES ROUGHLY 3Z TO 7Z
ALONG THE ELEVATED FRONT. FOR NOW..DECIDED TO GO WITH SLIGHT TO
CHANCE POPS ACROSS THE SOUTHERN KANSAS COUNTIES. AS FOR PRECIP
TYPE...MODEL SOUNDINGS IN THIS AREA STILL SHOW A GOOD DRY LAYER AT
THE SURFACE SUGGESTING POSSIBLE DRIZZLE IF ANYTHING AT ALL. WHILE
FREEZING DRIZZLE MIGHT BE POSSIBLE...SURFACE TEMPERATURES SHOULD
REMAIN NEAR OR ABOVE FREEZING THROUGH 7Z.
THE TROUGH AXIS CONTINUES TO PUSH EAST BY THURSDAY WITH THE CLOSED
LOW REMAINING OVER THE SOUTHWEST THROUGH THE PERIOD. RIDGING BEGINS
TO BUILD IN ACROSS THE WEST...AND REMAINS THROUGH THE REST OF THE
PERIOD. HIGH TEMPERATURES ARE EXPECTED TO BE IN THE LOW TO MID 50S
WITH LOWS IN THE UPPER 20S TO MID 30S. POPS REMAIN SOUTH OF THE
CWA BEGINNING 12Z THURSDAY.
.LONG TERM...SATURDAY THROUGH TUESDAY.
WE WILL KICK OFF THE LONG TERM WITH RATHER DISPARATE SOLUTIONS
BETWEEN MODELS. MODELS ARE GENERALLY INDICATING THAT AT 12Z
SATURDAY...A CLOSED LOW WILL BE LOCATED SOMEWHERE BETWEEN THE
SOUTHERN ROCKIES AND SOUTHWESTERN KANSAS...EXCEPT FOR THE CANADIAN
MODEL...WHICH PREDICTS A CLOSED LOW IN NORTHWESTERN MEXICO...NOT FAR
FROM WHERE THE GFS40 ADVERTISES A SECOND CLOSED LOW...WITH ITS
NORTHERN PREVIOUSLY MENTIONED CLOSED LOW BEING THE EASTERN OUTLIER
IN SOUTHWESTERN KANSAS ALONG WITH DGEX. THIS EASTERN TENDENCY HAS
HELD TRUE TO THE GFS FOR SOME TIME...ALTHOUGH SOLUTIONS ARE NOT
QUITE SO DISPARATE WITH THIS CLOSED LOW AS IT TRACKS
NORTHEAST...WHICH IS A PROMISING SIGN WHEN CONSIDERING THE LARGE
DISAGREEMENT AMONG THE LONG RANGE SOLUTIONS IN THE RECENT PAST.
CONSOLIDATING THE PROJECTED MODEL SOLUTIONS IS PREFERABLE OVER THE
WEEKEND...WITH THE AXIS OF THE LOW/TROUGH EXITING BY SUNDAY NIGHT.
TEMPERATURES SHOULD BE SEASONABLE FOR THE WEEKEND AND ABOVE NORMAL
INTO THE NEXT WORK WEEK WITHIN SOUTHWEST FLOW ALOFT. THE SECONDARY
CLOSED LOW OVER NORTHWESTERN MEXICO SHOULD HEAD EAST INTO TEXAS
AND BE TOO FAR SOUTH TO AFFECT US. AN AREA OF ISENTROPIC LIFT WILL
SPREAD NORTH IN ADVANCE OF THE APPROACHING LOW/TROUGH AND
CONTINUED WITH VERY LOW CHANCES OF PRECIPITATION GENERALLY
SATURDAY THROUGH SUNDAY. AGAIN...AFTER THE TROUGH PASSES...DRY AND
WARM WEATHER WILL PREVAIL FOR THE BEGINNING OF THE WORK WEEK.
.PREV DISCUSSION... /ISSUED 117 AM CST WED MAR 7 2012/
AVIATION...06Z KGRI TAF. WIND SPEEDS AND DIRECTION ARE A CONCERN
WITH THE APPROACHING COLD FRONT FROM THE NORTHWEST. SHORTLY AFTER
THE COLD FRONT PASSES EARLY THIS MORNING...WIND DIRECTION SHOULD
SHIFT TO THE NORTH WITH NOTICEABLE GUSTS...CONSIDERING THE
IMPRESSIVE HEIGHT RISES. A DECK OF STRATUS SHOULD SOON FOLLOW WITHIN A
COUPLE OF HOURS OF FRONT PASSAGE. JUDGING BY THE LATEST
INTERPOLATION TOOLS...I MAY BE TOO SLOW WITH FRONT PASSAGE...SO
MAY NEED TO UPDATE SO THAT THE COLD FRONT PASSAGE WILL BE CLOSER
TO 10Z TO 11Z. WIND SHOULD CONTINUE TO BE GUST BEHIND THE FRONT AS
LOW-LEVEL LAPSE RATES PROMOTE EFFICIENT MOMENTUM TRANSFER. KEPT
CEILINGS FROM DIPPING DOWN TO IFR...AND KEPT THEM AT MVFR
CONSIDERING MOST OBSERVATIONS UPSTREAM.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...SALTZMAN
LONG TERM/AVIATION...HEINLEIN
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
527 AM CST WED MAR 7 2012
.SHORT TERM...TODAY THROUGH FRIDAY NIGHT
310 AM CST WED MAR 7 2012
MAIN FORECAST CONCERNS ARE ON PRECIPITATION CHANCES TODAY INTO
TONIGHT AND TEMPERATURES THROUGH THE PERIOD.
LATEST SURFACE OBSERVATIONS SHOWED A COLD FRONT STRETCHING FROM
NORTH CENTRAL MINNESOTA SOUTHWEST INTO CENTRAL NEBRASKA.
THE COLD FRONT IS EXPECTED TO MOVE FROM WEST TO EAST ACROSS THE
FORECAST AREA THIS AFTERNOON. THE WARM SOUTHERLY FLOW WILL CONTINUE
ACROSS THE AREA THIS MORNING AHEAD OF THE FRONT. WITH VERY MILD
TEMPERATURES ALREADY IN PLACE ACROSS MUCH OF THE AREA THIS
MORNING...SHOULD HAVE NO PROBLEM WARMING INTO THE UPPER 50S TO LOWER
60S. ANOTHER CONCERN IS ON PLACEMENT OF PRECIPITATION AS THE FRONT
MOVES THROUGH. EARLY THIS MORNING...THE MOST OF THE CLOUD COVER WAS
POST FRONTAL WITH NO SIGNIFICANT PRECIPITATION BEING REPORTED.
HOWEVER...AS THE FRONT MOVES SOUTHEAST FRONTOGENESIS IS EXPECTED TO
INCREASE. THE FIRST BAND OF FRONTOGENESIS LOOKS TO SET UP IN THE
900-800 MB LEVEL. FORECAST SOUNDINGS SUPPORT LOW LEVEL SATURATION SO
SHOULD SEE THE DEVELOPMENT OF LIGHT RAIN ACROSS NORTHEAST
IOWA...SOUTHEAST MINNESOTA INTO WESTERN WISCONSIN THIS AFTERNOON.
THIS FRONTOGENESIS BAND APPEARS TO DEEPEN WITH TIME AS IT DRIFTS
SOUTHEAST INTO EXTREME NORTHEAST IOWA AND FAR SOUTHWEST WISCONSIN
LATE THIS AFTERNOON INTO THIS EVENING. SHOULD SEE THE RAIN BAND
BECOME MORE ORGANIZED AS IT MOVES SOUTHEAST DURING THE LATE
AFTERNOON INTO THE EVENING HOURS. EXTREME SOUTHWEST WISCONSIN MAY
PICK UP AROUND A QUARTER OF AN INCH OF RAINFALL OUT OF THIS SYSTEM
WITH 0.03 TO AROUND A TENTH OF INCH ELSEWHERE. PLAN ON FALLING
TEMPERATURES THIS AFTERNOON IN THE WAKE OF THE FRONT. THE RAIN IS
EXPECTED TO MOVE SOUTHEAST OF THE FORECAST AREA LATE THIS EVENING.
DEPENDING ON HOW QUICKLY THE COLDER AIR MOVES IN...WE COULD SEE
A BRIEF PERIOD OF LIGHT SNOW BEFORE THE PRECIPITATION ENDS. LOOK
FOR LOW TEMPERATURES TO RANGE FROM THE LOWER 20S ACROSS PORTIONS
OF NORTHEAST IOWA THROUGH NORTH CENTRAL WISCONSIN TO THE UPPER 20S
TO LOWER 30S ACROSS FAR SOUTHWEST WISCONSIN.
HIGH PRESSURE WILL EDGE INTO THE AREA LATE TONIGHT INTO THURSDAY.
850 MB TEMPERATURES WILL FALL 10 DEGREES FROM THIS AFTERNOON INTO
THURSDAY...WITH 850 MB TEMPS RANDING FROM -10 C ACROSS NORTH
CENTRAL WISCONSIN TO -5 C ACROSS NORTHEAST IOWA. AN UPPER LEVEL
TROUGH WILL SLIDE THROUGH THURSDAY AFTERNOON WITH THE POTENTIAL TO
BRING SOME CUMULUS CLOUDS TO THE AREA. PLAN ON HIGH TEMPERATURES
RANGING FROM THE UPPER 30S ACROSS NORTH CENTRAL WISCONSIN TO THE
LOWER 40S ACROSS NORTHEAST IOWA UNDER PARTLY SUNNY SKIES. FORECAST
SOUNDINGS ARE SHOWING THE POTENTIAL FOR A FEW RAIN/SNOW SHOWERS ON
THURSDAY WITH STEEP LAPS RATES IN PLACE. HOWEVER...LOW LEVEL
MOISTURE IS LACKING WITH TEMPERATURE/DEW POINT SPREADS OF 10
DEGREES ACROSS PORTIONS OF SOUTHEAST MINNESOTA INTO FAR SOUTHWEST
WISCONSIN. NORTH OF INTERSTATE 94...THERE MAY BE ENOUGH LOW LEVEL
MOISTURE TO PRODUCE VERTICALLY DEVELOPED CUMULUS TO PRODUCE LIGHT
RAIN OR SNOW SHOWERS. CONFIDENCE LOW ON THIS OCCURRING GIVEN HOW
DRY THE AIRMASS IS. WILL INCREASE CLOUD COVER ACROSS THESE AREAS
ON THURSDAY TO ACCOUNT FOR SHALLOW CUMULUS DEVELOPMENT. IT WILL BE
RATHER BREEZY ON THURSDAY WITH SURFACE LOW PRESSURE PASSING JUST
NORTH OF LAKE SUPERIOR AND HIGH PRESSURE ACROSS THE
DAKOTAS...PRODUCING A TIGHT PRESSURE GRADIENT ACROSS THE FORECAST
AREA. LOOK FOR WEST NORTHWEST WINDS OF 15 TO 25 MPH WITH GUSTS TO
AROUND 35 MPH. PLAN ON DECREASING CLOUDS THURSDAY EVENING AS
SURFACE COOLING COMMENCES. SURFACE HIGH PRESSURE WILL MOVE OVER
THE REGION ON FRIDAY PROVIDING SUNNY SKIES. LOOK FOR HIGH
TEMPERATURES TO RANGE FROM THE MID 30S ACROSS NORTH CENTRAL
WISCONSIN TO THE LOWER 40S ACROSS NORTHEAST IOWA. UPPER LEVEL
RIDGING IS EXPECTED TO PUSH INTO THE UPPER MISSISSIPPI RIVER
VALLEY FRIDAY NIGHT FROM THE NORTHERN PLAINS...WITH 850 MB
TEMPERATURES WARMING TO AROUND +6 C BY EARLY SATURDAY MORNING.
.LONG TERM...SATURDAY THROUGH TUESDAY
310 AM CST WED MAR 7 2012
UPPER LEVEL RIDGING IS EXPECTED ACROSS THE UPPER MISSISSIPPI RIVER
VALLEY ON SATURDAY AS AN UPPER LOW OVER THE FOUR CORNERS REGION
MEANDERS INTO THE CENTRAL PLAINS. PLAN ON HIGH TEMPERATURES ON
SATURDAY RANGING FROM THE UPPER 40S ACROSS NORTH CENTRAL WISCONSIN
TO THE LOWER 50S ACROSS WESTERN WISCONSIN INTO NORTHEAST IOWA.
07.00 MEDIUM RANGE MODELS CONTINUE TO SHOW DIFFERING SOLUTIONS
REGARDING THE THE EVOLUTION AND MOVEMENT OF THE FOUR CORNERS LOW
SATURDAY NIGHT INTO SUNDAY. THE ECMWF TAKES THE UPPER LOW INTO
EASTERN NEBRASKA SUNDAY AFTERNOON AND INTO THE FORECAST AREA
SUNDAY NIGHT. THE GFS IS A LITTLE FASTER AND BRINGS THE UPPER LOW
INTO CENTRAL IOWA SUNDAY AFTERNOON AND JUST BRUSHES SOUTHERN
PORTIONS OF THE FORECAST AREA SUNDAY NIGHT....WITH A SECOND UPPER
LOW DIVING SOUTH ACROSS SOUTHERN TEXAS. THE GEM LATCHES ONTO THE
SOUTHERN LOW SOLUTION AND TAKES THE LOW INTO TEXAS...LIFTING IT
INTO THE UPPER MISSISSIPPI RIVER VALLEY REGION SUNDAY NIGHT INTO
MONDAY. GIVEN THE SPREAD IN POTENTIAL SOLUTIONS WILL MAINTAIN A
MODEL CONSENSUS BLEND APPROACH SUNDAY INTO MONDAY. PLAN ON A
CHANCE OF RAIN ACROSS THE ENTIRE AREA SUNDAY INTO SUNDAY NIGHT
BEFORE THE LOW FINALLY EXITS THE AREA. WARM TEMPERATURES WILL
PERSIST MONDAY INTO TUESDAY WITH HIGHS IN THE 50S TO AROUND 60.
&&
.AVIATION...TODAY AND TONIGHT
527 AM CST WED MAR 7 2012
A COLD FRONT EXTENDED FROM NORTHEAST MINNESOTA INTO EASTERN
NEBRASKA THIS MORNING. DESPITE AN INCREASE IN MOISTURE AHEAD OF
THE FRONT...CONDITIONS HAVE REMAINED VFR AND EXPECT THEM TO DO SO
UNTIL JUST BEFORE THE FRONT PASSES THROUGH. BOTH THE 07.06Z NAM
AND 07.09Z RUC SUGGEST A MVFR CEILING WILL DEVELOP AS THE FRONT
APPROACHES. THE LACK OF ANY MVFR CONDITIONS CURRENTLY AHEAD OF THE
FRONT DOES NOT LEND A LOT OF CONFIDENCE TO THIS OCCURRING...BUT
HAVE RETAINED THIS TO MAINTAIN SOME CONTINUITY WITH PREVIOUS
FORECASTS. BELIEVE THE GREATEST LIKELIHOOD OF MVFR OR IFR
CONDITIONS OCCURRING WILL BE ONCE THE FRONT MOVES THROUGH AND THE
COLDER AIR QUICKLY COMES IN. THE NAM AND RUC SOUNDINGS SUGGEST IFR
AT KRST BEHIND THE FRONT BUT NOT FOR VERY LONG BEFORE THE CEILINGS
GO BACK UP TO MVFR. THIS IS ALSO SEEN IN THE 07.03Z SREF DATA
WHICH SHOWS A NARROW CORRIDOR OF IFR CONDITIONS RIGHT BEHIND THE
FRONT FOR ABOUT 3 HOURS OR SO. AS FOR THE RAIN...THE BEST CHANCES
APPEAR TO BE A COUPLE HOURS EITHER SIDE OF THE FRONTAL PASSAGE.
THERE MAY BE ENOUGH RAIN TO REDUCE THE VISIBILITY TO MVFR FOR A
WHILE...BUT CONFIDENCE IS NOT HIGH AS THE SREF DATA SHOWS ALMOST
NO PROBABILITIES FOR MVFR VISIBILITY FOR EITHER TAF SITE. BASED ON
THIS...SHORTENED UP THE PERIOD OF MVFR VISIBILITY FROM THE
PREVIOUS FORECAST. THE FORECAST SOUNDINGS SUGGESTS GOOD LOW LEVEL
LAPSE RATES WILL BE IN PLACE BOTH AHEAD OF AND BEHIND THE FRONT TO
MAINTAIN WINDS GUSTS THROUGH MUCH OF THE FORECAST PERIOD. DID DROP
THE GUSTS AT KLSE A COUPLE HOURS BEHIND THE FRONT PASSAGE AS A
NORTHWEST WIND IS NOT CONDUCIVE OF GUSTS IN THE VALLEY LOCATION.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
310 AM CST WED MAR 7 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...WETENKAMP
LONG TERM....WETENKAMP
AVIATION...04
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
440 PM EST WED MAR 7 2012
.DISCUSSION...
TONIGHT-THURSDAY...
HIGH PRES OVER THE W ATLC WILL MAINTAIN A TIGHT PGRAD ACRS EAST
CENTRAL FL THRU THU AFTN. STEADY E/SE FLOW WILL PREVAIL BUT WILL
DIMINISH GRADUALLY AS THE HIGH PRES DRIFTS SEAWARD BUT WILL REMAIN
BREEZY ALONG THE COAST.
LATEST RUC ANALYSIS SHOWING 80-85PCT MEAN RH THRU THE H100-H85 LYR
FROM THE CAPE SWD. THIS IS HIGH ENOUGH TO SHOULD SUPPORT ISOLD SHRAS
OVERNIGHT FROM THE CAPE DOWN TO THE N SHORE OF LAKE OKEECHOBEE.
DESPITE THE STRONG ERLY FLOW...LINGERING DRY AIR OVER THE INTERIOR
WILL PREVENT THE SHRAS FROM ADVECTING INTO THE NW HALF OF THE CWA.
EVEN SO...THE MOISTURE ADVECTION WILL MODIFY THIS DRY AIR ENOUGH TO
ALLOW ISOLD SHRAS TO DVLP AREAWIDE ON THU.
COMBINATION OF ONSHORE FLOW AND CLOUD COVER WILL KEEP MIN TEMPS
L/M60S OVER THE INTERIOR (5-10F ABV AVG)...M60S/L70S ALONG THE COAST
(10-15F ABV AVG). NEAR AVG MAX TEMPS THU AFTN...U70S/L80S ALONG THE
COAST...L/M80S INTERIOR.
THU NIGHT-FRI...RIDGE AXIS NORTH OF EAST CENTRAL FLORIDA WILL BEGIN
TO NUDGE SOUTH AND VEER WINDS SOUTHEASTERLY WHILE DIMINISHING THEM
TO 5 MPH OR LESS BY FRIDAY MORNING. KEPT SLIGHT RAIN CHANCES PINNED
TO THE COAST EXCEPT FOR NEAR THE TREASURE COAST WHERE SHOWER
COVERAGE WILL BE ABLE TO PENETRATE FURTHER INLAND WHERE HIGHER
MOISTURE RESIDES. EXPECT PATCHY FOG TO DEVELOP OVERNIGHT INTO FRIDAY
MORNING AS ATMOSPHERE DECOUPLES ALONG WITH AMPLE LINGERING LOW LEVEL
MOISTURE. CONTINUED ONSHORE FLOW WILL MAKE FOR OVERNIGHT LOW
TEMPERATURES IN THE LOW-MID 60S ACROSS THE INTERIOR AND MID-UPPER
60S ALONG THE COAST.
RIDGE AXIS SETTLES OVER THE AREA ON FRIDAY...ALLOWING WINDS TO
DECREASE TO 5-10 MPH THROUGHOUT THE DAY. PLUME OF ENHANCED MOISTURE
WILL BE DRAWN IN FROM THE BAHAMAS ON THE BACKSIDE OF THE ATLANTIC
RIDGE AS A WEAK AREA OF LOW PRESSURE APPROACHES FROM THE GULF.
PLACEMENT OF THIS LOW PRESSURE AREA HAS BEEN SOMEWHAT INCONSISTENT
IN MODEL RUNS...BUT THE PROXIMITY OF IT TO THE AREA WILL AID IN
MOISTURE ENHANCEMENT AND ALLOW FOR SLIGHT SHOWER CHANCES AREAWIDE.
TEMPERATURES WILL CONTINUE THEIR WARMING TREND MAKING IT INTO THE
LOW 80S ALONG THE COAST AND MIDDLE 80S INLAND.
WEEKEND (MODIFIED PREVIOUS)...BACK DOOR FRONT SLIDES INTO THE
NORTHERN PENINSULA AND WASHES OUT. COMBINATION OF MOISTURE
APPROACHING FROM NORTH ALONG WEAK FRONTAL BOUNDARY AND
AFOREMENTIONED MOISTURE PLUME SOUTH WILL KEEP SMALL SHOWER CHANCES
IN THE FORECAST THROUGH SATURDAY. LEFT SLIGHT CHANCE FOR SHOWERS
NORTH ON SUNDAY AT THIS TIME...BUT WILL HAVE TO MONITOR PROPAGATION
OF BOUNDARY IN SUBSEQUENT FORECASTS. ONSHORE WINDS WILL FRESHEN AS
ANOTHER AREA OF HIGH PRESSURE BUILDS OFF THE MID ATLANTIC
COAST...WHICH SHOULD KNOCK A FEW DEGREES OFF MAX TEMPS BUT STILL
KEEP THEM ABOVE NORMAL IN THE UPPER 70S TO LOWER 80S.
MON-WED...SURFACE HIGH PRESSURE RIDGE AXIS WILL REMAIN TO OUR
NORTH AND ONSHORE FLOW WILL CONTINUE. MOISTURE VALUES ARE FORECAST
TO BE LOWER AND MOS POPS ARE NEARLY UNIFORM AT 10-15 PERCENT THROUGH
THE PERIOD SO WILL NOT INCLUDE ANY POPS FOR THIS PERIOD. LITTLE
CHANGE IN ABOVE NORMAL TEMPS.
&&
.AVIATION...
THRU 08/00Z...ERLY SFC WNDS 15-20KTS WITH G24-28 KTS...CIGS BTWN
FL040-060. AFT 08/00Z...SCT OCNL BKN BTWN FL030-050 WITH ISOLD -SHRA
PSBL...N OF KISM-KTIX ERLY SFC WNDS BCMG 5-10KTS...S OF KTIX SFC
WNDS 10-15KTS WITH OCNL G20KTS.
&&
.MARINE...
TONIGHT-THURSDAY...HIGH PRES RIDGE OVER THE W ATLC WILL MAINTAIN A
FRESH TO STRONG E/SE BREEZE ACRS THE AREA OVERNIGHT. WINDS WILL
BEGIN TO DIMINISH THU AFTN AS THE RIDGE WEAKENS AND DRIFTS SEAWARD.
SEAS WILL BE SLOW TO SUBSIDE HOWEVER AS A MODERATE SWELL BEGINS TO
IMPACT THE AREA...6-8FT NEAR SHORE AND 8-10FT OFFSHORE...DOMINANT
PDS 8-9SEC. SCA IN PLACE THRU 08/00Z.
THU NIGHT-FRI...SOUTHEAST WINDS WILL DIMINISH FROM 15-20 KNOTS TO
AROUND 10 KNOTS BY FRIDAY EVENING AS RIDGE AXIS SETTLES ACROSS THE
AREA AND RELAXES THE PRESSURE GRADIENT. SEAS WILL ALSO SUBSIDE FROM
6-7 FEET TO 5-6 FEET NEARSHORE AND 7-9 FEET TO 5-8 FEET OFFSHORE
WITH EAST TO SOUTHEAST SWELLS OF 9-10 SECONDS.
SAT-SUN (MODIFIED PREVIOUS)...THE WATERS SHOULD START OUT IN A
RELATIVELY LOOSE GRADIENT ON SAT THEN A BACK DOOR FRONT DROPPING
SOUTH OVER THE ATLANTIC IS PROGGED TO GRADUALLY BECOME DIFFUSE...BUT
NORTHEAST/EAST WINDS SHOULD PICK UP TO 15-20 KNOTS SATURDAY
AFTERNOON. EAST WINDS ON SUNDAY LOOK TO BE NEAR 15 KNOTS.
&&
.FIRE WEATHER...
PREVAILING ONSHORE FLOW THROUGHOUT THE END OF THE WEEK WILL KEEP
MINIMUM RELATIVE HUMIDITY VALUES ABOVE 40 PERCENT. TRANSPORT WINDS
WILL DECREASE ON FRIDAY BUT PICK UP AGAIN FOR SATURDAY AND SUNDAY.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 63 78 62 80 / 10 20 10 20
MCO 61 84 62 85 / 10 20 10 20
MLB 67 80 66 82 / 10 20 10 20
VRB 68 80 65 82 / 20 20 10 20
LEE 60 83 62 84 / 10 20 10 20
SFB 62 83 63 83 / 10 20 10 20
ORL 61 84 63 84 / 10 20 10 20
FPR 68 80 66 82 / 20 20 10 20
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...LAKE WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR COASTAL
VOLUSIA-INDIAN RIVER-MARTIN-NORTHERN BREVARD-SOUTHERN
BREVARD-ST. LUCIE.
HIGH SURF ADVISORY UNTIL 10 PM EST THIS EVENING FOR COASTAL
VOLUSIA-INDIAN RIVER-MARTIN-NORTHERN BREVARD-SOUTHERN
BREVARD-ST. LUCIE.
AM...SMALL CRAFT ADVISORY UNTIL 7 PM EST THURSDAY FOR COASTAL WATERS
FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE OUT 20 NM-
COASTAL WATERS FROM SEBASTIAN INLET TO JUPITER INLET OUT 20
NM-COASTAL WATERS FROM VOLUSIA BREVARD COUNTY LINE TO
SEBASTIAN INLET OUT 20 NM-WATERS FROM FLAGLER BEACH TO
VOLUSIA BREVARD COUNTY LINE 20 TO 60 NM OFFSHORE-WATERS
FROM SEBASTIAN INLET TO JUPITER INLET 20 TO 60 NM OFFSHORE-
WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN INLET
20 TO 60 NM OFFSHORE.
&&
$$
SHORT TERM/AVIATION...BRAGAW
LONG TERM/IMPACT WX...GUSEMAN/PENDERGRAST
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
315 PM CST WED MAR 7 2012
.SYNOPSIS...
12Z UA ANALYSIS HAS A STRONG LLJ RUNNING FROM THE GULF COAST INTO
THE NORTHEAST. A STRONG CANADIAN COLD FRONT RAN FROM THE ARROWHEAD
OF MINNESOTA INTO SOUTHEAST COLORADO. A VERY PRONOUNCED MOISTURE
PLUME WAS OVER THE MID CONUS WITH 850MB DEW POINTS GETTING INTO THE
LOW TEENS IN SOUTH TEXAS. SATELLITE/RADAR TRENDS THROUGH MID
AFTERNOON SHOW A LARGE EXPANSE OF MID CLOUDS WITH LOW CLOUDS ALONG
AND BEHIND THE COLD FRONT. RADARS SHOW PRECIPITATION DEVELOPING
ALONG AND BEHIND THE FRONT FROM IOWA INTO MINNESOTA.
18Z SFC ANALYSIS HAD A WEAK LOW NEAR KRPD IN NORTHWEST WISCONSIN
WITH THE COLD FRONT FROM NEAR THE LOW BACK INTO THE OKLAHOMA
PANHANDLE NEAR KGUY. A SUBTLE PRE-FRONTAL TROF RAN FROM NEAR KRST TO
KFNB. DEW POINTS AHEAD OF THE FRONT WERE IN THE 40S AND 50S THAT
QUICKLY DROP INTO THE 20S AND 30S AND FINALLY TEENS BEHIND THE FRONT.
&&
.SHORT TERM...TONIGHT AND THURSDAY...
GFS MOISTURE INITIALIZATION WAS WAY TOO MOIST AGAIN WITH ERRORS OF
3-5C COMMON IN THE LOWEST LAYERS. THE WRF WAS BETTER BUT STILL TOO
MOIST. ALTHOUGH THE RUC WAS SLIGHTLY TOO MOIST...IT WAS DEPICTING
QUITE WELL WHAT WAS HAPPENING AND ITS TRENDS WERE USED HEAVILY FOR
TONIGHT. THE ECMWF/GEM/UKMET WERE FAVORED FOR THURSDAY.
RUC TRENDS COMBINED WITH RECENT RADAR TRENDS INDICATE THAT PRECIP
WILL BE MAINLY ALONG/BEHIND THE FRONT. THE WAA TOOL USING THE RUC AT
THE 925MB SFC AGREES QUITE WELL ON HOW PRECIP HAS DEVELOPED SO FAR.
THUS PRECIP WILL DEVELOP/MOVE INTO THE NORTHWEST CWFA LATE THIS
AFTERNOON/EVENING. SOME PRE-FRONTAL SHOWERS MAY OCCUR LATE THIS
AFTERNOON WITH PEAK HEATING. PER THE LIFT TOOL...THE BEST CHANCES
FOR ANY ISOLATED TSRA WILL BE OVER THE NEXT 4-6 HRS IN THE NORTHWEST
PART OF THE CWFA. THUS WILL INCLUDE A MENTION OF ISOLATED THUNDER
THERE.
ONCE THE COLD FRONT PASSES ANY ONE AREA...TEMPERATURES SHOULD DROP
ABOUT 15 DEGREES IN JUST OVER AN HOUR.
BETWEEN MID EVENING AND MIDNIGHT AREAL COVERAGE OF THE RAIN WILL
EXPAND AS THE FRONT CONTINUES MOVING SOUTHEAST. THE EVENING HOURS
WILL BE THE MOST LIKELY TIME PERIOD FOR THE RELATIVELY HEAVIER RAIN
AMOUNTS BUT EVEN THAT AMOUNT WILL BE UNDER ONE QUARTER INCH.
JUST PRIOR TO MIDNIGHT SOME SNOW MAY MIX IN WITH THE RAIN BEFORE IT
ENDS ACROSS THE FAR NORTHWEST CWFA. AT THE VERY WORST A LOCALIZED
DUSTING MAY OCCUR.
AFTER MIDNIGHT THE RAIN WILL END FROM NORTHWEST TO SOUTHEAST AS
CONDENSATION PRESSURE DEFICITS RISE AND THE BETTER FORCING MOVES
EAST OF THE CWFA. MOST OF THE CWFA SHOULD BE PRECIPITATION FREE BY
SUNRISE. THE INCOMING HIGH PRESSURE MAY ALLOW SKIES TO PARTIALLY
CLEAR. LOW TEMPERATURES WILL OCCUR AT OR SHORTLY AFTER SUNRISE
THURSDAY.
ON THURSDAY...SOME LINGERING SPRINKLES MAY BE SEEN IN THE FAR EAST
AND SOUTHEAST PARTS OF THE CWFA BEFORE ENDING BY MID MORNING. HIGH
PRESSURE BUILDING IN SHOULD ALLOW SKIES TO CLEAR FURTHER BEFORE HIGH
CLOUDS MOVE BACK INTO THE AREA. LOW LEVEL LAPSE RATES ARE REASONABLY
STEEP AND SHOULD PROMOTE GOOD MIXING AND RESULT IN ANOTHER BREEZY IF
NOT WINDY DAY. HIGH TEMPERATURES SHOULD BE 15-20 DEGREES COLDER BUT
STILL ABOVE NORMAL. ..08..
.LONG TERM...THURSDAY NIGHT THROUGH NEXT WEDNESDAY...
ABOVE NORMAL TO WELL ABOVE NORMAL WITH LIGHT RAIN CHANCES SUNDAY INTO
MONDAY.
OVERALL...INITIALIZATION AND VERIFICATION AVERAGE WITH ONCE AGAIN
SIGNIFICANT BL PROBLEMS WITH LOW LEVEL THERMAL (TOO COOL) AND
MOISTURE FIELDS (TOO HIGH). HI-RES ECMWF HANDLING THIS AND ALSO RUN
TO RUN CONTINUITY THE BEST. LIKELY GUIDANCE TEMPERATURES DAYS 3-7
ARE AT LEAST A CATEGORY OR TWO TOO LOW...OR MAY NEED RAISING 3-5
DEGREES FOR HIGHS MOST DAYS.
THURSDAY NIGHT...WINDS MAY DECOUPLE UNDER A FAIR SKY...IF SO THEN
MINS MAY NEED TO BE TRIMMED BY UP TO 3 DEGREES. THIS WOULD RESULT
IN LOWS IN THE LOWER TO MIDDLE 20S.
FRIDAY THROUGH SATURDAY...FAIR SKIES AND WARMING TREND. LIGHT SOUTH
WINDS AND COPIOUS SUNSHINE TO MAKE FOR COMFORTABLE MARCH WEATHER.
HIGHS MAY APPROACH 60S IN SOME SECTIONS ON SATURDAY. MINS SATURDAY
AM WITHIN A FEW DEGREES OF 32F AND SUNDAY AM AROUND 40F.
SUNDAY AND MONDAY...AREAS OF LIGHT TO POSSIBLY MODERATE RAIN...MOSTLY
SUNDAY. HAVE KEPT CHANCE POPS AS TREND HAS BEEN A TRACK A BIT SOUTH
THE PAST 3 DAYS. BEST FORCING SOUTH AND SUGGEST TOTAL RAIN AMOUNTS TO
BE GENERALLY BELOW A QUARTER INCH MOST LOCATIONS. HIGHS SUNDAY TO BE
IMPACTED BY AMOUNT OF CLOUD COVER. SKIES TO CLEAR MONDAY WITH HIGHS
WELL INTO THE 60S. MINS SUNDAY AND MONDAY MORNING IN THE 40S MOST
LOCATIONS.
TUESDAY AND WEDNESDAY...DRY WITH WELL ABOVE NORMAL TEMPERATURES.
HIGHS IN THE 60S WITH LOWS IN THE 40S AND LOWER 50S ON THURSDAY
MORNING. SOME LOW LEVEL THERMAL FIELDS SUGGEST 70S POSSIBLE ON ONE
OR MORE DAYS WITH ENOUGH HEATING FOR LATER SHIFTS TO RECONSIDER.
THESE TEMPERATURES ARE 15-20 DEGREES ABOVE NORMAL. ..NICHOLS..
&&
.AVIATION...
COLD FRONT HAS MOVED THROUGH KALO AND WILL BE MOVING THROUGH ALL TAF
SITES BY 04Z/08. PRECIPITATION IS DVLPG ALONG AND BEHIND THE FRONT
WITH MVFR CONDITIONS. ISOLATED TSRA MAY DEVELOP THROUGH 03Z/08 THAT
COULD AFFECT KCID/KDBQ. IF NO TSRA DEVELOPS BY 00Z/08 THEN THE TSRA
THREAT WILL BE ZERO. A FEW PIREPS INDICATE LLWS IS VERY MARGINAL AND
WILL CONTINUE TO DECREASE WITH THE APPROACH OF THE FRONT. VFR
CONDITIONS ARE EXPECTED TO DEVELOP AFT 06Z/08. ..08..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
08/NICHOLS
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1108 AM CST WED MAR 7 2012
.UPDATE...
MODEL VERIFICATION AND INITIALIZATION CONTINUES TO SHOW THE GFS
WAY TOO MOIST FROM THE BOUNDARY LAYER TO THE SFC BY 4-5C. THE WRF
IS SLIGHTLY BETTER BUT NOT BY MUCH. THE RUC TRENDS...ALBEIT
SLIGHTLY OVERDONE ARE BY FAR MUCH BETTER AND WILL BE FOLLOWED AS
TRENDS FOR THE AFTERNOON HOURS.
RUC CONDENSATION PRESSURE DEFICITS AND FORCING SHOW PRECIP NOT
REACHING THE FAR NORTHWEST PART OF THE CWFA UNTIL ABOUT MID
AFTERNOON. THE WAA TOOL HAS THE BEST CONVERGENCE ALONG/BEHIND THE
FRONT THROUGH LATE AFTERNOON BUT THERE IS AN INCREASE IN
CONVERGENCE AHEAD OF THE FRONT. THIS INCREASE AHEAD OF THE FRONT
IS LIKELY DUE TO THE RUC BRINGING UP A LARGER AXIS OF 50+ DEW
POINT AIR THAN WHAT THE CURRENT OBS AND OBS TRENDS INDICATE.
HOWEVER...THIS SIGNAL CANNOT BE ENTIRELY IGNORED BECAUSE THIS IS
RIGHT AT AND SHORTLY AFTER PEAK HEATING. THUS POPS HAVE BEEN RE-
WORKED FOR THE AFTERNOON HOURS AHEAD OF THE FRONT WITH A MORE
APPROPRIATE WORDING OF ISOLD/SCT SHRA.
THE RUC SHOW CONVERGENCE ALONG/BEHIND THE FRONT INCREASES
SIGNIFICANTLY RIGHT AROUND AND AFTER 00Z. IF CORRECT...THEN THIS
WOULD BE THE MOST LIKELY TIME PERIOD FOR THE RELATIVELY HEAVIER
RAIN AND POSSIBLE ISOLD TSRA WITH THE STRONGEST FORCING PRESENT.
CLOUD COVER IS HELPING TO HOLD DOWN TEMPERATURES SOMEWHAT BUT THE
STRONG WAA IS SLOWLY PUSHING TEMPERATURES UP. COMPRESSIONAL
HEATING JUST AHEAD OF THE FRONT MAY ALLOW TEMPERATURES TO LOCALLY
CLIMB HIGHER LATE THIS AFTERNOON. BEHIND THE FRONT TEMPERATURES
SHOULD BEGIN TO FALL PRIOR TO SUNSET.
AN UPDATE TO THE FCST IS ALREADY AVAILABLE.
..08..
&&
.AVIATION...
THE GFS MODEL IS TOO MOIST IN THE LOW LEVELS WITH THE WRF ONLY
SLIGHTLY BETTER. RUC MODEL IS BETTER AND RUC TRENDS SUGGEST A
FRONTAL PASSAGE ARND 00Z/09 AT KCID AND KDBQ/KMLI/KBRL 00Z-
06Z/08. VFR CONDITIONS AHEAD OF THE FRONT WITH POSSIBLE MVFR
CONDITIONS RIGHT ALONG AND IMMEDIATELY BEHIND IT. CONVERGENCE
ALONG THE FRONT INCREASES 00Z-03Z/09 WHICH MAY ALLOW ISOLATED
TSRA TO DVLP. FOR THE 18Z TAFS WILL ADD CB WORDING TO KMLI/KBRL TO
REFLECT THIS. LLWS THREAT IS MARGINAL AT 20KTS THROUGH 00Z/08.
..08..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS DODGE CITY KS
1008 AM CST WED MAR 7 2012
.UPDATE...
ISSUED AT 1004 AM CST WED MAR 7 2012
HAVE UPDATED WINDS AND TEMPERATURES FOR THE REST OF TODAY WITH A
FASTER MOVING COLD FRONT. THE FRONT HAS ALREADY MOVED THROUGH HAYS,
DODGE CITY, GARDEN CITY, TO NEAR LIBERAL. LOOK FOR NEARLY STEADY
TEMPERATURES IN THE MID TO UPPER 40S BEHIND THE FRONT, AND HIGHS
IN THE MID 60S AHEAD OF THE FRONT AROUND MEDICINE LODGE.
&&
.SHORT TERM...(TODAY THROUGH TONIGHT)
ISSUED AT 403 AM CST WED MAR 7 2012
SYNOPSIS:
AT 00Z LAST NIGHT...A LARGE ANTICYCLONICALLY CURVED JET EXTENDED FROM
THE SOUTHERN COAST OF ALASKA TO THE ALBERTA ROCKIES
SOUTH-SOUTHWESTWARD TO NEAR SAN FRANCISCO LEADING TO THE DEVELOPING
MID LEVEL CYCLONE...WHICH WAS CENTERED OVER THE SIERRA NEVADA AT
THAT TIME. 150 TO 200 METER 12-HOUR HEIGHT FALLS WERE FOUND AHEAD
OF THE DEVELOPING CYCLONE AT 500MB. COLD MID LEVELS WERE ALSO
OBSERVED WITH 700MB TEMPERATURES -15 TO -18C ACROSS EASTERN
WASHINGTON AND OREGON TO WESTERN MONTANA AND NORTHERN NEVADA. AHEAD
OF THE DEVELOPING CYCLONE...700MB TEMPERATURES WERE +5 TO +7C OVER
THE SOUTHERN ROCKIES AND SOUTHERN PLAINS. AT 00Z...THE 850MB FRONT
EXTENDED SOUTHWEST FROM A LOW CENTER NEAR THE MANITOBA-NORTH
DAKOTA-MINNESOTA BORDER TO THE BLACK HILLS REGION. AS OF 09Z...THE
FRONT AT THE SURFACE EXTENDED FROM NEAR SIOUX FALLS, SOUTH DAKOTA
SOUTHWEST WARD TO NORTHWEST KANSAS. THE FRONT HAD JUST PASSED
THROUGH GOODLAND, KS WITH A NORTH-NORTHWEST WIND OBSERVED.
TODAY:
THE FRONT WILL CONTINUE TO PUSH SOUTH...REACHING AN ELKHART TO
GARDEN CITY TO LACROSSE LINE BY LATE MORNING. TEMPERATURES WILL
FALL ABRUPTLY UPON THE INITIAL PASSAGE OF THE FRONT...THEN CONTINUE
A SLOW DECLINE OR HOLD NEARLY STEADY FOR THE REMAINDER OF THE DAY AS
WARMING THROUGH INSOLATION IS OFFSET BY COLD ADVECTION. BY LATE
AFTERNOON...THE UPPER LOW WILL STILL BE WELL TO THE WEST OVER THE
FOUR CORNERS. NO MEASURABLE PRECIPITATION IS EXPECTED DURING THE
"TODAY" PERIOD (ENDING 00Z) AND HAVE REMOVED ALL POPS AS A RESULT
FOR TODAY. SOME OF THE SHORT TERM HIGH RESOLUTION MODELS DO HINT AT
SOME PATCHY DRIZZLE/REAL LIGHT SHOWERS ACROSS CENTRAL KANSAS PERHAPS
CLIPPING STAFFORD COUNTY BY LATE AFTERNOON... AND I DO HAVE SOME
"SILENT" POPS LESS THAN 15 PERCENT TO COVER THIS...BUT ANY
MEASURABLE PRECIPITATION SHOULD HOLD OFF UNTIL AFTER 00Z.
TONIGHT:
A REALLY COMPLICATED FORECAST FOR TONIGHT. ALL THE MODELS HAVE
TRENDED DOWNWARD IN PRECIPITATION POTENTIAL/AMOUNTS FOR THE MAJORITY
OF THE DDC FORECAST AREA AND AS A RESULT...POPS HAVE BEEN LOWERED
ACROSS THE BOARD. IN FACT...AREAS NORTHWEST OF A LAKIN TO GARDEN
CITY TO JETMORE LINE MAY NOT SEE MUCH IN THE WAY OF PRECIPITATION AT
ALL TONIGHT. AS THE FRONT CONTINUES TO PUSH SOUTH INTO
OKLAHOMA...DRIER AIR WILL BE MOVING IN. SHOWERS AND THUNDERSTORMS
WILL EVENTUALLY DEVELOP ALONG THE FRONT IN THE 850-900MB LAYER AS
INDICATED BY ECMWF, GFS, AND CANADIAN GEM...BUT THIS WILL MOST
LIKELY BE REALIZED ACROSS THE FAR SOUTHEASTERN COUNTIES (COMANCHE
AND BARBER). ELEVATED CAPE FROM AN 800MB PARCEL WOULD SUGGEST
AROUND 400-600 J/KG UP INTO BARBER COUNTY...SO SOME SMALL HAIL
WITH ANY CONVECTION WILL BE POSSIBLE. OTHER LIGHTER SHOWERS MAY DEVELOP
FARTHER NORTH WHERE THE FRONTOGENESIS EXISTS HIGHER UP IN THE
TROPOSPHERE WITH THE SLOPING COLD FRONT...BUT ALL MODELS INSIST
THAT THE MORE SUBSTANTIAL PRECIPITATION PRODUCTION WILL BE TIED TO
FRONTOGENESIS LOWER IN THE TROPOSPHERE...AND THUS FARTHER SOUTH.
WILL KEEP THE AREAS OF DRIZZLE/LIGHT FREEZING DRIZZLE IN THE GRIDS
FOR ROUGHLY THE SOUTHEASTERN HALF AS THE NAM AND SOME VERSIONS OF
THE WRF SUGGEST THE LIGHT PRECIPITATION SIGNAL IN SIMULATED
REFLECTIVITY FIELDS. THAT BEING SAID...THE DRY AIR ADVECTION FROM
THE NORTH MAY JUST BE TOO MUCH TO OVERCOME AS THE STRONGEST
900-800MB FRONTOGENESIS WILL BE, AGAIN, SOUTH OF THE DDC FORECAST
AREA BY LATE IN THIS PERIOD. ANY SHALLOW LAYER PRECIPITATION
SHOULD BE FAIRLY SHORT-LIVED AND MOVE SOUTH OF THE AREA BY 12Z OR
SHORTLY THEREAFTER.
.LONG TERM...(THURSDAY THROUGH TUESDAY)
ISSUED AT 231 AM CST WED MAR 7 2012
THURSDAY:
THE UPPER LEVEL LOW WILL BE SOUTH OF THE DDC FORECAST AREA. NAM/GFS
AN TOO A LESSER EXTENT THE GEM KEEP MOST OF THE HEAVIER
PRECIPITATION SOUTH OF THE AREA. THE 00Z ECMWF IS A LITTLE BIT MORE
GENEROUS WITH QPF. DECIDED TO KEEP CHANCE POPS ACROSS THE REGION. AN
EXAMINATION OF FORECAST SOUNDINGS SHOW THAT THE LOW LEVELS BELOW 700
HPA ARE SUB-SATURATED AND THE DENDRITIC LAYER IS NOT REALLY
SATURATED EITHER. DECIDED TO KEEP DRIZZLE AND FREEZING DRIZZLE IN
THE FORECAST SHOULD THE CLOUD DECK BECOME THICK ENOUGH. WARMED HIGHS
UP GIVEN THE MORE DRY SOLUTION THAT THE MODELS HAVE TURNED TO.
FRIDAY:
THE 00Z ECMWF DOESN`T MOVE UPPER LEVEL LOW THAT MUCH FRIDAY AND IS
WAY LESS PROGRESSIVE THAN COMPARED TO THE NAM/GFS. AS A RESULT, KEPT
SOME SOME SLIGHT TO CHANCE POPS ACROSS SOUTHWEST KANSAS. THE EURO
DOES INDICATE SOME SNOWFALL ACROSS EXTREME SOUTHWEST KANSAS.
SOMETHING TO WATCH AS NONE OF THE OTHER MODELS SUGGEST SUCH
ACCUMULATIONS.
WEEKEND AND BEYOND:
CONFIDENCE IS LOW THIS FAR OUT. SOME SHOWERS ARE POSSIBLE SATURDAY
IF THE ECMWF PANS OUT. OTHERWISE, THE FORECAST WILL DRY OUT AND
TEMPERATURES WILL WARM UP AS 500 HPA HEIGHTS INCREASE AND LOW LOW
THICKNESS FIELDS INCREASE AS WELL. TEMPERATURE LOOK TO BE ABOVE
NORMAL AT THE END OF THE PERIOD.
&&
.AVIATION...(FOR THE 15Z TAFS THROUGH 15Z THURSDAY MORNING)
ISSUED AT 918 AM CST WED MAR 7 2012
SURFACE OBSERVATIONS IS SHOWING THE FRONT IS MOVING FASTER THAN MODELS
SUGGEST. HRRR SEEMS TO BE DOING BETTER WITH THE FRONT TIMING AND WAS
USED IN THE 12Z TAFS. MVFR CIGS WILL GRADUALLY MOVE SOUTH ACROSS
HAYS AND GARDEN CITY BY 18Z. THEN POSSIBLE INTO KDDC BY 20Z. LATER
TONIGHT MVFR CIGS ARE EXPECTED IN ASSOCIATION WITH STRATUS AND
FREEZING DRIZZLE.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 50 31 44 30 / 10 40 40 40
GCK 42 30 42 27 / 0 20 50 30
EHA 44 27 38 25 / 0 30 60 50
LBL 50 30 38 26 / 0 40 50 40
HYS 45 30 49 29 / 10 20 20 20
P28 62 36 45 35 / 10 70 70 30
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
UPDATE...KRUSE
SHORT TERM...UMSCHEID
LONG TERM....SUGDEN
AVIATION...KRUSE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1241 PM EST WED MAR 7 2012
.UPDATE...
ISSUED AT 959 AM EST WED MAR 7 2012
MADE SOME MINOR ADJUSTMENTS TO THE FORECAST...LARGELY TO DEAL WITH
THE TEMPERATURES AND FOG. NOT MUCH FOG ACROSS UPPER MI AND WI THIS
MORNING AND IT APPEARS TO BE LARGELY ASSOCIATED WITH THE SFC FRONT
FARTHER W NEAR KDLH. THUS...HAVE TAPERED BACK FOG MENTION TO BE
LOCATED ALONG THE FRONTAL BOUNDARY. DID LEAVE MENTION ALONG LK MI
THIS AFTN...AS WARM MOIST AIR WILL BE MOVING ACROSS THE RELATIVELY
COOL LK MI WATERS. DID RAISE HIGHS A COUPLE DEGREES FOR TODAY...AS
LIMITED FALL OVERNIGHT HAS KEPT VALUES IN THE 40S AND LOW 50S THIS
MORNING. THINK THE INCREASING CLOUDS AND PCPN STARTING TO DEVELOP
ALONG THE MN/WI BORDER BETWEEN KMSP-KDLH WILL KEEP TEMPS FROM RISING
MUCH ABOVE THE LOW 50S.
&&
.SYNOPSIS...
ISSUED AT 523 AM EST WED MAR 7 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A POSITIVE TILT MID/UPPER
LEVEL TROUGH FROM SASK/MANITOBA TOWARD A CLOSED LOW OVER SRN NEVADA
RESULTING IN SW FLOW FROM THE CNTRL PLAINS TO THE WRN GREAT LAKES.
AT THE SFC...A TROUGH/FRONT EXTENDED FROM NW ONTARIO AND NE MN INTO
ERN NEBRASKA. SOME LIGHT SNOW HAD DEVELOPED BEHIND THE FRONT OVER
ERN ND INTO FAR NW MN. OTHERWISE...NO PCPN WAS OBSERVED ALONG OR
AHEAD OF THE FRONT. VERY MILD AIR HAD SPREAD INTO THE REGION AHEAD
OF THE FRONT ON SSW WINDS WITH TEMPS OVERNIGHT CLIMBING INTO THE 40S
ACROSS MUCH OF WEST AND CENTRAL UPPER MI. BNDRY LAYR MIXING HAS
HELPED KEEP DEWPOINT DEPRESSIONS HIGH ENOUGH TO LIMIT ANY FOG
DEVELOPMENT.
&&
.SHORT TERM...(TODAY THROUGH THURSDAY)
ISSUED AT 523 AM EST WED MAR 7 2012
MODELS HAVE CONTINUED WITH TREND TOWARD A LATER ARRIVAL OF THE
FRONT...MOVING INTO IWD AFT 18Z AND TO MQT-IMT BY 00Z. MOISTURE CONV
AND 900-700 MB FGEN ASSOCIATED WITH THE FRONT SHOULD BE ENOUGH TO
SUPPORT DEVELOPMENT AND INCREASING COVERAGE OF LIGHT PCPN BAND
THROUGH WRN UPPER MI IN THE AFTERNOON. PCPN MAY ALSO SPREAD INTO THE
ERN PORTION OF THE CWA WITH 290K-295K ISENTROPIC ASCENT AHEAD OF THE
FRONT. FCST SOUNDINGS SUPPORT LIQUID PCPN OVER MOST OF THE AREA WITH
POTENTIAL FOR CHANGEOVER TO FROZEN PCPN OVER THE FAR WEST LATE. WITH
A SUBSTANTIAL DRY 750-600 MB LAYER AND FREEZING LEVEL ABOVE THE MOIST
LAYER...LACK OF ICE CRYSTALS WOULD LEAD TO LIGHT ACCUMULATIONS OF
MAINLY DRIZZLE. THE NAM/GFS SUGGEST THAT A SHORTWAVE AND STRONGER
850-600 MB FGEN BEHIND THE FRONT WILL REMAIN MAINLY TO THE NW OF THE
CWA...STREAKING THROUGH NW LAKE SUPERIOR.
ENOUGH OF A COLD LAYER MAY DEVELOP BEHIND THE FRONT BY LATE
AFTERNOON WEST AND INTO THE EVENING CENTRAL WITH A SMALL LAYER NEAR
800-750 MB AT OR ABOVE 0C FOR A VERY BRIEF PERIOD OF SOME SLEET.
HOWEVER...ONCE THE DEEPER MOISTURE AND COLD AIR ARRIVE FROM WEST TO
EAST...THE PRECIP TYPE SHOULD CHANGE OVER FROM DZ/PL TO SNOW. WITH
ONLY A BRIEF PERIOD FOR ANY SNOW POSSIBLE...ANY ACCUMULATIONS SHOULD
AMOUNT TO LESS THAN A HALF INCH. LAKE ENHANCED SNOW POTENTIAL OVER
THE WEST WITH NW FLOW BEHIND THE FRONT WILL BE LIMITED BY THE
MARGINAL INSTABILITY AND QUICK ARRIVAL OF DRIER AIR AND LOW INVERSIO
HEIGHTS NEAR 3K FT.
THURSDAY...AS THE MID LEVEL TROUGH SLIDES INTO THE AREA MODERATE TO
STRONG 850-500 MB QVECTOR CONV...DAYTIME HEATING AND STEEP 900-700
MB LAPSE RATES WILL SUPPORT SCT SHSN DURING THE AFTERNOON. ANY LAKE
EFFECT CONTRIBUTION WILL ONLY BE MARGINAL WITH 850 MB TEMPS ONLY TO
AROUND -11C.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 523 AM EST WED MAR 7 2012
MODELS IN GOOD AGREEMENT THAT UPR TROUGH AND COLDER AIR DIGS FM
NORTHERN CANADA THURSDAY INTO THE EASTERN CANADA THURSDAY NIGHT.
THIS PROVIDES GLANCING BLOW OF FAIRLY CHILLY AIR /H85 TEMPS AS LOW
AS -18C/ ACROSS ONTARIO AND THE UPR GREAT LAKES ON THURSDAY NIGHT.
SHORTWAVE/UPR JET IS FCST TO DIG FM THE CANADIAN PRAIRIES INTO THE
BASE OF THE TROUGH THURSDAY NIGHT...BUT MAJORITY OF H85-H7/H7-H5
Q-VECTOR CONVERGENCE WILL ALREADY BE TO THE NORTH AND EAST OF LK
SUPERIOR EARLY THURSDAY EVENING WITH SUBSIDENCE SPREADING ACROSS
UPR MICHIGAN. EVEN WITH THE SUBSIDENCE...DEEP AND COLD TROUGH LEADS
TO MOIST PROFILE AOA H9 THROUGH H6 AND STEEP LAPSE RATES UP TO 8C/KM
WITHIN THAT MOIST LAYER PER GFS/NAM SOUNDINGS NEAR LK SUPERIOR. SNOW
SHOWERS THURSDAY NIGHT WILL PROBABLY BE PRETTY CONVECTIVE/SPLOTCHY
IN COVERAGE. BLYR WINDS ARE STEADILY VEERING FM WNW TO NW THROUGH
THE NIGHT WHICH LIMITS LK EFFECT IN ANY ONE PARTICULAR AREA...THOUGH
SEEMS THAT HIGHER TERRAIN OF WESTERN UPR MI AND AREAS EAST OF
MARQUETTE TO NEWBERRY WOULD STAND TO SEE THE MOST SNOW WITH NW WIND
FCST AT H925/H85.
BY LATE THURSDAY NIGHT...SNOW SHOWERS SHOULD DIMINISH AS THERE IS
CONSENSUS THAT MOISTURE AOA H8 DRIES OUT AND SINCE TEMPS AT
900MB-925MB ARE NOT THAT COOL AT ONLY AROUND -10C. DO SEE SOME
COOLING IN THE H9-H8 LAYER ON FRIDAY AS SECONDARY COLD FRONT SLIDES
ACROSS LK SUPERIOR AND UPR MICHIGAN. FCST SOUNDING AT ERY AT THE END
OF THE FETCH SHOW MOISTENING H95-H8 WITH SOME DRY AIR LINGERING BLO
H95. NOT MUCH SHEAR OR DIRECTIONAL CHANGES IN THE MOIST LAYER SO LK
EFFECT COULD GET BETTER ORGANIZED FOR A TIME IN THE MORNING BEFORE
DAYTIME DRYING AND INCREASING SUBSIDENCE FM ARRIVAL OF SFC RIDGE
LEADS TO DIMINISHING TREND IN THE AFTN. EXPECT ALL LK EFFECT TO
FINISH UP FRIDAY EVENING AS SFC RIDGE AND WARM AIR ADVECTION ARRIVE
IN EARNEST.
IN THE EXTENDED...
WARM AIR ADVECTION ON SATURDAY IS QUITE VIGOROUS AND THERE ARE SOME
PRETTY BEEFY S/SW 1000-850MB WINDS FCST FM GFS/ECMWF IN THE RETURN
FLOW REGIME. IN FACT...H925-H85 WINDS FM BOTH MODELS ARE AOA 45 KTS.
GIVEN THESE LOW-LEVEL WINDS...TIGHTENING PRESSURE GRADIENT BTWN
RIDGE DEPARTING INTO CNTRL GREAT LAKES AND SHARP NORTH-TO-SOUTH
ORIENTED SFC TROUGH PRESSING ACROSS CNTRL CANADA...AND VERY STRONG
PRESSURE FALLS SETTING UP JUST NORTH OF LK SUPERIOR...SATURDAY COULD
BE A BREEZY DAY EVEN WITH THE HIGHER STABILITY DUE TO THE STRONG
WARM AIR ADVECTION/INVERSION. MODELS SEEM TO BE LATCHING ONTO THIS
MORE WINDY TREND. SHOULD SEE HIGHS ON SATURDAY SIMILAR TO THOSE SEEN
YESTERDAY...MAINLY MID-UPR 40S WITH TEMPS STAYING IN THE UPR 30S TO
AROUND 40 DEGREES DOWNWIND OF COOLER LK MICHIGAN WATERS.
MAIN PRECIPITATION CHANCES IN EXTENDED ARE IN THE SUNDAY THROUGH
MONDAY TIME FRAME. AGREEMENT FM THE MODELS REMAINS LOW IN HOW FAR
NORTH UPR LOW CURRENTLY OVER THE DESERT SW WILL BE PROPELLED INTO
GREAT LAKES. ADDED UNCERTAINTY IS LATEST MODEL RUNS REMAIN
CONSISTENT WITH PREVIOUS MODEL RUNS. ECMWF BRINGS UPR LOW INTO UPR
MICHIGAN LATE SUNDAY INTO SUNDAY NIGHT WITH A PERIOD OF RAIN
SHOWERS. GFS KEEPS THE LOW MORE OVR OHIO VALLEY...MISSING CWA WITH
ANY RAINFALL. CANADIAN LOOKS LIKE THE ECMWF BUT IS JUST SLOWER IN
BRINGING THE SYSTEM INTO UPR MICHIGAN. NO REAL TIP OFF TO BUDGE OFF
CONSENSUS AT THIS POINT. SO...HAVE POPS OVER MAINLY SOUTHERN CWA ON
SUNDAY AND MID RANGE CHANCE POPS OVR MOST CWA SUNDAY NIGHT. ONE
TREND THAT IS DEVELOPING IS THE ECMWF SHOWING IT JUST COLD ENOUGH ON
BACKSIDE OF THE SYSTEM BY MONDAY TO HAVE A CHANCE OF SNOW OVR THE
WESTERN CWA. JUST CANNOT GO THIS WAY AT THIS POINT...GIVEN THE LACK
OF AGREEMENT FM THE MODELS IN THE FIRST PLACE. ESSENTIALLY KEPT WHAT
WE HAD GOING WHICH WAS STAYING WARM WITH CHANCE OF RAIN SUNDAY INTO
MONDAY. NO CONFIDENCE AFTER MONDAY AS GFS/ECMWF BECOME COMPLETELY
OUT OF PHASE WITH EACH OTHER. CONSENSUS FCST OF SLIGHT CHANCE POPS
FOR RAIN SHOWERS WITH TEMPS STAYING WARM WORKS FOR NOW UNTIL MORE
SUBSTANTIAL TRENDS CAN BE BETTER IDENTIFIED.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON)
ISSUED AT 1238 PM EST WED MAR 7 2012
RAIN STARTING TO DEVELOP OVER NW WI ALONG THE COLD FRONT
STRETCHING FROM THE TIP OF THE ARROWHEAD OF MN THROUGH KMSP.
MOISTURE ALONG THE FRONT HAS ALSO LED TO SOME PATCHY/AREAS OF
FOG/DZ TO GO ALONG WITH THE STRONGER SHOWERS. EXPECT THESE LOWER
CIGS/VSBYS TO AFFECT KIWD/KCMX THIS EVENING AS THE MAIN ENERGY
MOVES NE. AS THE FRONT MOVES E ACROSS UPPER MI THIS AFTN AND EARLY
EVENING...EXPECT THE PRECIP TO BECOME MORE SHOWERY AS IT NEARS KSAW
AND ONLY HAVE PERIODS OF LOWER CIGS/VSBYS TO IFR CONDITIONS.
ONCE THE FRONT MOVES THROUGH...EXPECT A W TO E TRANSITION TO -SHSN
AS COLDER AIR SPILLS OVER LK SUPERIOR. THINK THIS WILL LARGELY LEAD
TO LOWER CIGS...BUT COULD SEE PERIODS OF STRONGER -SHSN TO REDUCE
VSBYS TO MVFR CATEGORY. WEDGE OF DRIER AIR WILL MOVE OVER THE WRN
CWA THURS MORNING AND BRING AN END TO THE LOWER CLOUDS AND -SHSN.
HELD ON TO THE CLOUDS LONGER AT KSAW DUE TO LINGERING LLVL MOISTURE
AND NNW FLOW.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 523 AM EST WED MAR 7 2012
GUSTY SW WINDS TO 30 KTS STILL POSSIBLE TODAY OVER EASTERN SECTIONS
AHEAD OF APPROACHING COLD FRONT. ONCE FRONT MOVES THROUGH...MAY SEE
NW WINDS TO 30 KTS INTO THURSDAY OVER MUCH OF THE LAKE. AS COLDER
AIR FLOWS ACROSS LK SUPERIOR THURSDAY NIGHT...INCREASINGLY UNSTABLE
THERMAL PROFILE WITH 30-40 KT WINDS IN MIXED LAYER SUGGEST A GALE
WATCH MAY EVENTUALLY BE NEEDED. MODELS ARE NOT IN AGREEMENT WITH
STRENGTH OF WINDS SO HAVE HELD OFF ON ANY HEADLINE FOR NOW AND JUST
MENTIONED GALE GUSTS. STRONGER WINDS AND HIGH WAVES WITH A BRIEF SHOT
OF COLDER AIR RESULTS IN POTENTIAL FOR HEAVY FREEZING SPRAY OVR CNTRL
AND EASTERN LK SUPERIOR LATER THURSDAY NIGHT. WINDS AND WAVES
DIMINISH LATER FRIDAY WITH ARRIVAL OF HIGH PRESSURE RIDGE BUT THERE
COULD BE ANOTHER STRONGER PERIOD OF SOUTH- SOUTHWEST WINDS LATE
FRIDAY NIGHT THROUGH SATURDAY. IT IS A SITUATION WITH WARM AIR RIDING
OVR THE COOLER LAKE WATERS...BUT STRONG PRESSURE FALLS NORTH OF THE
LAKE AND TIGHT PRESSURE GRADIENT COULD PROVIDE ENOUGH BOOST TO SEE
GALES. WINDS DIMINISH TO LESS THAN 25 KTS BY SUNDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...SRF
SYNOPSIS...JLB
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...SRF
MARINE...JLA
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1251 PM CST WED MAR 7 2012
.UPDATE...SENT A MINOR UPDATE TO AFTERNOON FORECAST TO TWEAK
AFTERNOON TEMPERATURES AS PERSISTENT CLOUD COVER HAS HELPED TO
KEEP TEMPS DOWN SO FAR TODAY. EVEN SO...EXPECT A FEW BREAKS IN
CLOUD COVER AS WE TRANSITION THROUGH THE AFTERNOON HOURS...AS
EVIDENT UPSTREAM IN SATELLITE IMAGERY...WITH AN ADDITIONAL FEW
DEGREES OF WARMING FROM CURRENT LEVELS BY LATE AFTERNOON. ALSO
WENT AHEAD AND REMOVED ANY MENTION OF PRECIP FOR THE REMAINDER OF
THE AFTERNOON...AS WELL AS TWEAKED BACK CHANCES FOR TONIGHT
AS NEW MODEL DATA COMING IN IS NOT VERY BULLISH ON ANY PRECIP
DEVELOPING ACROSS OUR AREA OVERNIGHT...WITH A VERY TIGHT
PRECIPITATION GRADIENT EXPECTED NEAR THE FRONTAL BOUNDARY JUST TO
OUR SOUTHEAST. NO OTHER CHANGES NECESSARY AT THIS TIME.
&&
.PREV DISCUSSION... /ISSUED 1217 PM CST WED MAR 7 2012/
AVIATION...18Z KGRI TAF...MVFR CIGS ARE EXPECTED TO CONTINUE FOR
A FEW MORE HOURS AT KGRI...WITH CEILINGS SLOWLY IMPROVING THROUGH
THE LATE AFTERNOON HOURS...AS THIS MORNINGS COLD FRONT CONTINUES
TO PUSH FURTHER SOUTHEAST. IN ADDITION...STRONG NORTHERLY WINDS
ARE EXPECTED TO RELAX AND BECOME LESS GUSTY AFTER AROUND
08/02Z AS SUN SETS AND PRESSURE GRADIENT SLACKENS...WITH
PREVAILING VFR CONDITIONS EXPECTED THEREAFTER.
PREV DISCUSSION... /ISSUED 424 AM CST WED MAR 7 2012/
SHORT TERM...TODAY THROUGH FRIDAY NIGHT.
UPPER AIR ANALYSIS INDICATES A DEEP UPPER LEVEL TROUGH AXIS
MOVING ONTO THE WEST COAST WHILE THE EASTERN HALF OF THE UNITED
STATES REMAINS UNDER A WEAK AMPLITUDE RIDGE IN MOSTLY ZONAL FLOW.
AT 500 MB...THE RIDGE AXIS REMAINS SITUATED ALONG THE EAST COAST
WITH A TROUGH AXIS ALONG THE WEST COAST. AT THE SURFACE...HIGH
PRESSURE REMAINS OFF THE EAST COAST WHILE LOW PRESSURE HAS
DEVELOPED ACROSS THE NEVADA/ARIZONA STATE LINE. LOOKING AT WATER
VAPOR IMAGERY...THIS LOW PRESSURE SYSTEM HAS KICKED UP QUITE A
MOISTURE/CLOUD FIELD ACROSS THE HIGH PLAINS AND WESTERN CENTRAL
PLAINS.
MODELS STILL INDICATE A CLOSED UPPER LEVEL LOW ACROSS NEVADA HELPING
PUSH A STRONG COLD FRONT THROUGH THE PLAINS. THE FRONT IS STILL
PEGGED TO MOVE THROUGH THE REGION THIS MORNING. LATEST MOSAIC RADAR
IMAGERY AND METARS SHOW THE FRONT HAS MADE IT TO NORTHWEST PORTION
OF THE CWA BY 10Z. WINDS BEHIND THE FRONT WERE ALREADY NEAR 25 KNOTS
WITH GUSTS AROUND 30 KTS.
MODEL SOLUTIONS ARE TRENDING TOWARDS INCREASED WIND SPEEDS BEHIND
THE FRONT. THE NAM SOLUTION SHOWS 3 HOUR HEIGHT RISES TO NEAR 9MB AT
12Z AND THE HRRR MODELS ALSO SUGGESTS HIGHER WIND SPEEDS ACROSS THE
NORTHWEST WITH WIND GUSTS NEAR 35 KTS. DECIDED TO INCREASE WINDS ON
THE BACKSIDE OF THE FRONT. HOWEVER...WHILE WINDS WILL BE BREEZY
DURING THE MORNING HOURS...EXPECT ANY WINDS THAT REACH WIND ADVISORY CRITERIA
TO BE SHORT LIVED.
REGARDING POPS WEDNESDAY THROUGH THURSDAY...BOTH THE GFS AND THE EC
KEEP SLIGHT POPS ACROSS THE EAST WITH THE FRONTAL PASSAGE DURING THE
DAY. BY WEDNESDAY NIGHT...BOTH MODELS PUSH THE SURFACE LOW FARTHER
SOUTH...THUS MOVING POPS FARTHER SOUTH. HOWEVER...THE 0Z WRF TRIES
TO FIRE OFF SOME SHOWERS ACROSS THE KANSAS COUNTIES ROUGHLY 3Z TO 7Z
ALONG THE ELEVATED FRONT. FOR NOW..DECIDED TO GO WITH SLIGHT TO
CHANCE POPS ACROSS THE SOUTHERN KANSAS COUNTIES. AS FOR PRECIP
TYPE...MODEL SOUNDINGS IN THIS AREA STILL SHOW A GOOD DRY LAYER AT
THE SURFACE SUGGESTING POSSIBLE DRIZZLE IF ANYTHING AT ALL. WHILE
FREEZING DRIZZLE MIGHT BE POSSIBLE...SURFACE TEMPERATURES SHOULD
REMAIN NEAR OR ABOVE FREEZING THROUGH 7Z.
THE TROUGH AXIS CONTINUES TO PUSH EAST BY THURSDAY WITH THE CLOSED
LOW REMAINING OVER THE SOUTHWEST THROUGH THE PERIOD. RIDGING BEGINS
TO BUILD IN ACROSS THE WEST...AND REMAINS THROUGH THE REST OF THE
PERIOD. HIGH TEMPERATURES ARE EXPECTED TO BE IN THE LOW TO MID 50S
WITH LOWS IN THE UPPER 20S TO MID 30S. POPS REMAIN SOUTH OF THE
CWA BEGINNING 12Z THURSDAY.
LONG TERM...SATURDAY THROUGH TUESDAY.
WE WILL KICK OFF THE LONG TERM WITH RATHER DISPARATE SOLUTIONS
BETWEEN MODELS. MODELS ARE GENERALLY INDICATING THAT AT 12Z
SATURDAY...A CLOSED LOW WILL BE LOCATED SOMEWHERE BETWEEN THE
SOUTHERN ROCKIES AND SOUTHWESTERN KANSAS...EXCEPT FOR THE CANADIAN
MODEL...WHICH PREDICTS A CLOSED LOW IN NORTHWESTERN MEXICO...NOT FAR
FROM WHERE THE GFS40 ADVERTISES A SECOND CLOSED LOW...WITH ITS
NORTHERN PREVIOUSLY MENTIONED CLOSED LOW BEING THE EASTERN OUTLIER
IN SOUTHWESTERN KANSAS ALONG WITH DGEX. THIS EASTERN TENDENCY HAS
HELD TRUE TO THE GFS FOR SOME TIME...ALTHOUGH SOLUTIONS ARE NOT
QUITE SO DISPARATE WITH THIS CLOSED LOW AS IT TRACKS
NORTHEAST...WHICH IS A PROMISING SIGN WHEN CONSIDERING THE LARGE
DISAGREEMENT AMONG THE LONG RANGE SOLUTIONS IN THE RECENT PAST.
CONSOLIDATING THE PROJECTED MODEL SOLUTIONS IS PREFERABLE OVER THE
WEEKEND...WITH THE AXIS OF THE LOW/TROUGH EXITING BY SUNDAY NIGHT.
TEMPERATURES SHOULD BE SEASONABLE FOR THE WEEKEND AND ABOVE NORMAL
INTO THE NEXT WORK WEEK WITHIN SOUTHWEST FLOW ALOFT. THE SECONDARY
CLOSED LOW OVER NORTHWESTERN MEXICO SHOULD HEAD EAST INTO TEXAS
AND BE TOO FAR SOUTH TO AFFECT US. AN AREA OF ISENTROPIC LIFT WILL
SPREAD NORTH IN ADVANCE OF THE APPROACHING LOW/TROUGH AND
CONTINUED WITH VERY LOW CHANCES OF PRECIPITATION GENERALLY
SATURDAY THROUGH SUNDAY. AGAIN...AFTER THE TROUGH PASSES...DRY AND
WARM WEATHER WILL PREVAIL FOR THE BEGINNING OF THE WORK WEEK.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
AVIATION/UPDATE...ROSSI
SHORT TERM...BDS
LONG TERM...HEINLEIN
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1217 PM CST WED MAR 7 2012
.AVIATION...18Z KGRI TAF...MVFR CIGS ARE EXPECTED TO CONTINUE FOR
A FEW MORE HOURS AT KGRI...WITH CEILINGS SLOWLY IMPROVING THROUGH
THE LATE AFTERNOON HOURS...AS THIS MORNINGS COLD FRONT CONTINUES
TO PUSH FURTHER SOUTHEAST. IN ADDITION...STRONG NORTHERLY WINDS
ARE EXPECTED TO RELAX AND BECOME LESS GUSTY AFTER AROUND
08/02Z AS SUN SETS AND PRESSURE GRADIENT SLACKENS...WITH
PREVAILING VFR CONDITIONS EXPECTED THEREAFTER.
&&
.PREV DISCUSSION... /ISSUED 424 AM CST WED MAR 7 2012/
SHORT TERM...TODAY THROUGH FRIDAY NIGHT.
UPPER AIR ANALYSIS INDICATES A DEEP UPPER LEVEL TROUGH AXIS
MOVING ONTO THE WEST COAST WHILE THE EASTERN HALF OF THE UNITED
STATES REMAINS UNDER A WEAK AMPLITUDE RIDGE IN MOSTLY ZONAL FLOW.
AT 500 MB...THE RIDGE AXIS REMAINS SITUATED ALONG THE EAST COAST
WITH A TROUGH AXIS ALONG THE WEST COAST. AT THE SURFACE...HIGH
PRESSURE REMAINS OFF THE EAST COAST WHILE LOW PRESSURE HAS
DEVELOPED ACROSS THE NEVADA/ARIZONA STATE LINE. LOOKING AT WATER
VAPOR IMAGERY...THIS LOW PRESSURE SYSTEM HAS KICKED UP QUITE A
MOISTURE/CLOUD FIELD ACROSS THE HIGH PLAINS AND WESTERN CENTRAL
PLAINS.
MODELS STILL INDICATE A CLOSED UPPER LEVEL LOW ACROSS NEVADA HELPING
PUSH A STRONG COLD FRONT THROUGH THE PLAINS. THE FRONT IS STILL
PEGGED TO MOVE THROUGH THE REGION THIS MORNING. LATEST MOSAIC RADAR
IMAGERY AND METARS SHOW THE FRONT HAS MADE IT TO NORTHWEST PORTION
OF THE CWA BY 10Z. WINDS BEHIND THE FRONT WERE ALREADY NEAR 25 KNOTS
WITH GUSTS AROUND 30 KTS.
MODEL SOLUTIONS ARE TRENDING TOWARDS INCREASED WIND SPEEDS BEHIND
THE FRONT. THE NAM SOLUTION SHOWS 3 HOUR HEIGHT RISES TO NEAR 9MB AT
12Z AND THE HRRR MODELS ALSO SUGGESTS HIGHER WIND SPEEDS ACROSS THE
NORTHWEST WITH WIND GUSTS NEAR 35 KTS. DECIDED TO INCREASE WINDS ON
THE BACKSIDE OF THE FRONT. HOWEVER...WHILE WINDS WILL BE BREEZY
DURING THE MORNING HOURS...EXPECT ANY WINDS THAT REACH WIND ADVISORY CRITERIA
TO BE SHORT LIVED.
REGARDING POPS WEDNESDAY THROUGH THURSDAY...BOTH THE GFS AND THE EC
KEEP SLIGHT POPS ACROSS THE EAST WITH THE FRONTAL PASSAGE DURING THE
DAY. BY WEDNESDAY NIGHT...BOTH MODELS PUSH THE SURFACE LOW FARTHER
SOUTH...THUS MOVING POPS FARTHER SOUTH. HOWEVER...THE 0Z WRF TRIES
TO FIRE OFF SOME SHOWERS ACROSS THE KANSAS COUNTIES ROUGHLY 3Z TO 7Z
ALONG THE ELEVATED FRONT. FOR NOW..DECIDED TO GO WITH SLIGHT TO
CHANCE POPS ACROSS THE SOUTHERN KANSAS COUNTIES. AS FOR PRECIP
TYPE...MODEL SOUNDINGS IN THIS AREA STILL SHOW A GOOD DRY LAYER AT
THE SURFACE SUGGESTING POSSIBLE DRIZZLE IF ANYTHING AT ALL. WHILE
FREEZING DRIZZLE MIGHT BE POSSIBLE...SURFACE TEMPERATURES SHOULD
REMAIN NEAR OR ABOVE FREEZING THROUGH 7Z.
THE TROUGH AXIS CONTINUES TO PUSH EAST BY THURSDAY WITH THE CLOSED
LOW REMAINING OVER THE SOUTHWEST THROUGH THE PERIOD. RIDGING BEGINS
TO BUILD IN ACROSS THE WEST...AND REMAINS THROUGH THE REST OF THE
PERIOD. HIGH TEMPERATURES ARE EXPECTED TO BE IN THE LOW TO MID 50S
WITH LOWS IN THE UPPER 20S TO MID 30S. POPS REMAIN SOUTH OF THE
CWA BEGINNING 12Z THURSDAY.
LONG TERM...SATURDAY THROUGH TUESDAY.
WE WILL KICK OFF THE LONG TERM WITH RATHER DISPARATE SOLUTIONS
BETWEEN MODELS. MODELS ARE GENERALLY INDICATING THAT AT 12Z
SATURDAY...A CLOSED LOW WILL BE LOCATED SOMEWHERE BETWEEN THE
SOUTHERN ROCKIES AND SOUTHWESTERN KANSAS...EXCEPT FOR THE CANADIAN
MODEL...WHICH PREDICTS A CLOSED LOW IN NORTHWESTERN MEXICO...NOT FAR
FROM WHERE THE GFS40 ADVERTISES A SECOND CLOSED LOW...WITH ITS
NORTHERN PREVIOUSLY MENTIONED CLOSED LOW BEING THE EASTERN OUTLIER
IN SOUTHWESTERN KANSAS ALONG WITH DGEX. THIS EASTERN TENDENCY HAS
HELD TRUE TO THE GFS FOR SOME TIME...ALTHOUGH SOLUTIONS ARE NOT
QUITE SO DISPARATE WITH THIS CLOSED LOW AS IT TRACKS
NORTHEAST...WHICH IS A PROMISING SIGN WHEN CONSIDERING THE LARGE
DISAGREEMENT AMONG THE LONG RANGE SOLUTIONS IN THE RECENT PAST.
CONSOLIDATING THE PROJECTED MODEL SOLUTIONS IS PREFERABLE OVER THE
WEEKEND...WITH THE AXIS OF THE LOW/TROUGH EXITING BY SUNDAY NIGHT.
TEMPERATURES SHOULD BE SEASONABLE FOR THE WEEKEND AND ABOVE NORMAL
INTO THE NEXT WORK WEEK WITHIN SOUTHWEST FLOW ALOFT. THE SECONDARY
CLOSED LOW OVER NORTHWESTERN MEXICO SHOULD HEAD EAST INTO TEXAS
AND BE TOO FAR SOUTH TO AFFECT US. AN AREA OF ISENTROPIC LIFT WILL
SPREAD NORTH IN ADVANCE OF THE APPROACHING LOW/TROUGH AND
CONTINUED WITH VERY LOW CHANCES OF PRECIPITATION GENERALLY
SATURDAY THROUGH SUNDAY. AGAIN...AFTER THE TROUGH PASSES...DRY AND
WARM WEATHER WILL PREVAIL FOR THE BEGINNING OF THE WORK WEEK.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
SHORT TERM...BDS
LONG TERM...HEINLEING
AVIATION...ROSSI
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1256 PM EST WED MAR 7 2012
.SYNOPSIS...
A RIDGE OF HIGH PRESSURE OVER THE REGION WILL SLOWLY MOVE EAST
THROUGH THURSDAY. A COLD FRONT WILL CROSS THE AREA ON FRIDAY
FOLLOWED BY CANADIAN HIGH PRESSURE BUILDING IN OVER THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1255 PM WED...WITH CIGS SCATTERING OUT OVER THE NC
PIEDMONT...TEMPS HAVE WARMED MORE THAN EXPECTED. MAX TEMPS HAVE BEEN
ADJUSTED UP TO REFLECT THIS. TEMPS/DEWPOINTS AND WINDS ARE BEHAVING
THEMSELVES ACROSS THE REST OF THE FA.
AS OF 1010 AM WED...CLOUD COVER IS HOLDING TOUGH ACROSS MOST OF THE
FA...WITH THE EXCEPTION OF THE NC PIEDMONT EAST OF I-77. A LITTLE
DRIER AIR IS WORKING TOWARD THE SRN ZONES FROM THE MIDLANDS.
HOWEVER...THE RUC SHOWS LLVL RH AT THE 850MB LAYER ACTUALLY
INCREASING OVER MOST OF THE FA THIS AFTN. SO WHILE THE SRN AND ERN
TIER WILL SEE PERIODS OF SUN...MOST OF THE REST OF THE FA IS
EXPECTED TO REMAIN CLOUDY WITH JUST OCCASIONAL BREAKS. THE SHRA
HAVEN/T PANNED OUT SO FAR...BUT I/LL KEEP SLIGHT CHANCES ALONG THE
SRN ESCARPMENT. TEMPS AND DEWPOINTS SO FAR LOOK GOOD.
PREVIOUS DISCUSSION...
EXPECT ISENTROPIC LIFT AND WEAK UPSLOPE FLOW WITH LOWERING AND
THICKENING CLOUD COVER. THERE SHOULD BE ENOUGH LOW LEVEL MOISTURE
FOR SLIGHT CHC POPS TO DEVELOP ALONG THE SW BLUE RIDGE IN AREAS OF
BEST UPSLOPE FLOW. EVEN WITH MCLOUDY SKIES LATER TODAY...HIGHS WILL
WARM TO NEAR AVG WITH ABOVE AVG HEIGHTS AND INCREASING S FLOW. AS
DEEPER MOISTURE SURGES N TONIGHT EXPECT A SLIGHT CHC OF LGT SHWRS
ALONG THE BLUE RIDGE ESCARPMENT AND ADJACENT FOOTHILLS/MTNS...FROM
NE GA UP THRU THE CAROLINAS. OVERNIGHT TEMPS SHOULD STAY WARM ENOUGH
FOR ALL RAIN ACROSS THE AREA EXCEPT FOR PSBLY A LITTLE SNOW MIXING
IN ON SOME OF THE HIGHER PEAKS AND RIDGES.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 300 AM WEDNESDAY...GUIDANCE IN GOOD AGREEMENT ON A NORTHERN
STREAM TROF AMPLIFYING OVER THE GREAT LAKES...FORCING A COLD FRONT
SEWD ACRS THE OH VLY ON THURSDAY. MEANWHILE...UPPER RIDGING LINGERS
OVER THE SOUTHEAST STATES...AND THIS CAUSES THE FRONT TO LAY OVER
THE TN VLY AND MID ATLANTIC IN A MORE W-E FASHION THU NGT. THE
STRONGEST UPPER FORCING AND LLVL MOISTURE TRANSPORT ALONG THE
STALLING BNDRY LOOKS TO BE SET UP ACRS THE MID SOUTH/TN VLY TO OUR
WEST. FORCING OVER THE CWFA LOOKS BE CONFINED MAINLY TO FRONTAL
CONVERGENCE AND WLY UPSLOPE FLOW ACRS THE NC MTNS. SO WILL GO WITH
CATEGORICAL TO LIKELY POPS THERE. TO THE EAST...EVEN THO MODELS ARE
IN GOOD AGREEMENT...I WILL KEEP THE POPS BELOW LIKELY DUE TO THE
LACK OF FORCING. TEMPS WILL BE ABOVE NORMAL BOTH THU AND FRI.
GUIDANCE HAS ALSO COME INTO BETTER AGREEMENT ON PUSHING THE
FRONT THRU THE AREA FRI NGT AS A BACKDOOR FRONT. FAIRLY STRONG SFC
HIGH PRES WILL BUILD OVER THE GREAT LAKES AND CENTRAL
APPALACHIANS...STRENGTHENING DRY NELY LLVL FLOW. I NOW HAVE POPS
TAPERING BACK TO LESS THAN 15% BY DAYBREAK SATURDAY. TEMPS SHUD ALSO
BE NOTICEABLY COOLER...BUT STILL ABOVE NORMAL.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
AT 245 AM EST WEDNESDAY...A COMPLICATED AND FAIRLY LOW CONFIDENCE
POST FROPA PATTERN EXISTS FOR THE EARLY EXT RANGE. THE MODELS ARE
NOW LATCHING ONTO THE IDEA OF THE STACKED CP HIGH BUILDING IN FROM
THE NORTH EARLY SAT AND REDUCING ANY GOOD CHANCE OF PRECIP BELOW
CLIMO. WINDS IN THE SFC TO H8 LAYER ARE NE/LY AT KHKY THROUGH 18Z
SAT AND DISTINCTLY LOWER POT TEMP DOMES OVER MOST OF THE AREA
THROUGH 12Z SUN. SO...POPS HAVE BEEN CUT BACK TO NEGLIGIBLE SAT WITH
SOME MEASURE REMNANT MOISTURE AND ISEN LIFT ENABLING ISOL -SHRA
LATER SAT INTO SUN ACROSS MAINLY THE SOUTHERN 2/3RDS OF THE CWFA.
THE PATTERN BECOMES LESS CERTAIN WITH THE VARYING IDEAS ON THE UPPER
LOW PLACEMENT AND ASSOCIATED NRN GOM CYCLOGENESIS. POPS WERE AGAIN
CUT BACK FOR SUN NIGHT INTO MON BASED ON CONFIDENCE...BUT LOW END
CHANCE WAS MAINTAINED ACROSS THE WRN ZONES WITH THE HIGH CENTER
MOVING OFF SHORE AND A MOIST RETURN FLOW POSSIBLY ENHANCED BY A SRN
LA FRONTAL WAVE. DONT EXPECT MUCH IN THE WAY OF THUNDER ACTIVITY
THROUGH THE PERIOD...BUT BY MON THE ATMOS WILL BECOME MORE UNSTABLE
AND THE LLVL KINEMATICS MORE CONDUCIVE TO SUPPORT GENERAL TSTMS.
WITH THE CANADIAN AIR MASS MIX SAT/SUN...MAX TEMPS WILL BE HELD
BELOW NORMAL BY A CAT OR SO...THEN A QUICK WARMUP TO ABOVE NORMAL
MON IS EXPECTED AS A DEEP SW/LY FLOW STRENGTHENS.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
AT KCLT...VFR CIGS IN THE 5-6KFT RANGE WILL LAST THROUGH MIDNIGHT.
WITH INCREASING LOW LEVEL MOISTURE...CIGS SHOULD FALL THROUGH THE
MVFR CAT AFTER MIDNIGHT...WITH A FEW HOURS OF IFR EXPECTED BY
SUNRISE. WINDS WILL GENERALLY BE OUT OF THE S TO SE THROUGH THE
PERIOD.
ELSEWHERE...VFR CIGS IN THE 5-6KFT RANGE WILL CONTINUE THROUGH LATE
EVENING ACROSS THE FOOTHILLS AND PIEDMONT. OCCASIONAL MVFR ARE
POSSIBLE AT KAVL THROUGH THE REST OF THE AFTN. CIGS WILL LOWER
THROUGH THE MVFR CAT OVERNIGHT...WITH IFR CONDITIONS GRADUALLY
DEVELOPING TOWARD SUNRISE. KAVL MAY NOT SEE CIGS QUITE THIS LOW AS
THE FLOW ISN/T QUITE AS UP THE VALLEY AS I/D LIKE TO SEE. ISOLATED
SHRA WILL CONTINUE TO THE SOUTH OF KAVL...AND A VCSH MAY NEED TO BE
ADDED.
OUTLOOK...RESTRICTIVE CIGS AND WIDESPREAD RAIN ARE EXPECTED THU
NIGHT AND EARLY FRIDAY. CIGS WILL RISE AND MAY CLEAR FRI NIGHT AND
SAT AS A FRONT DROPS SOUTH OF THE AREA. LOWER CIGS WILL RETURN SAT
NIGHT AND SUN AS THE FRONT LIFTS BACK TO THE NORTH.
AN EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLE SHOWING THE
PERCENTAGE OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED ISSUANCE
CATEGORY IS AVAILABLE AT FOLLOWING LINK (USE LOWER CASE)...
WWW.WEATHER.GOV/GSP/AVIATION/TABLES.HTM
&&
.GSP WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
NC...NONE.
SC...NONE.
&&
$$
SYNOPSIS...SBK
NEAR TERM...MCAVOY
SHORT TERM...ARK
LONG TERM...SBK
AVIATION...MCAVOY
AREA FORECAST DISCUSSION ...CORRECTION IN EXTENDED PERIOD
NWS LA CROSSE WI
240 PM CST WED MAR 7 2012
.SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT
240 PM CST WED MAR 7 2012
MAIN FORECAST CONCERNS ARE ON PRECIPITATION CHANCES TONIGHT/BREEZY
CONDITIONS THURSDAY/PRECIPITATION CHANCES AGAIN SATURDAY NIGHT.
SURFACE MAP AT 2 PM THIS AFTERNOON HAD AN AREA OF LOW PRESSURE OVER
SOUTHERN ONTARIO WITH A COLD FRONT EXTENDING THROUGH NORTHWEST
WISCONSIN INTO SOUTHEAST MN/CENTRAL IA. RADAR SHOWING INCREASING
ECHOES ALONG AND IMMEDIATELY BEHIND THE FRONT IN STRONG SFC TO 850MB
FRONTOGENESIS. A FEW SURFACE OBSERVATIONS STARTING TO REPORT LIGHT
RAIN UNDER THESE ECHOES AS WELL. OTHERWISE...A VERY SHARP
TEMPERATURE GRADIENT EXISTED ACROSS THE COLD FRONT WITH 50S TO A FEW
MIDDLE 60S AHEAD OF THE FRONT...AND THE MIDDLE 30S ALMOST
IMMEDIATELY BEHIND THE FRONT.
07.12Z NCEP MODELS/07.09Z SREF SHOWING GOOD AGREEMENT THROUGH THE
SHORT TERM PERIOD.
LOOK FOR THE COLD FRONT TO SLOWLY EXIT SOUTHEAST OF THE AREA THIS
EVENING WITH PRECIPITATION ENDING AROUND MIDNIGHT FOR MOST OF THE
AREA. TEMPERATURE PROFILE MAY SUPPORT A RAIN/SNOW MIX AS THE COLDER
AIR FILTERS IN BEHIND THE FRONT. OTHERWISE...EXPECT BRISK NORTHWEST
WINDS OVERNIGHT IN COLD AIR ADVECTION AND FAIRLY TIGHT PRESSURE
GRADIENT. OVERNIGHT LOWS EXPECTED TO BOTTOM OUT IN THE 20-30 DEGREE
RANGE.
COLDER CYCLONIC FLOW WILL BE IN PLACE ON THURSDAY WITH MODELS
SHOWING A FAIRLY VIGOROUS MID-LEVEL PV-ANOMALY/SURFACE TROUGH
DROPPING SOUTHEAST ACROSS THE AREA DURING THE AFTERNOON HOURS. THIS
WILL PRODUCE A STEEP 0-1KM LAPSE RATE ACROSS THE AREA FOR CUMULUS
DEVELOPMENT ALONG WITH A CHANCE FOR SNOW SHOWERS MAINLY NORTH OF
HIGHWAY 10 IN WISCONSIN. ALONG WITH TROUGH PASSAGE AND DEEP MIXING
TO AROUND 800MB...EXPECT GUSTY NORTHWEST WINDS WITH GUSTS REACHING
30-40 MPH THROUGH THE AFTERNOON. OTHERWISE...LOOK FOR HIGHS IN THE
MID 30S TO MID 40S.
HIGH PRESSURE BUILDS INTO THE AREA FRIDAY FOR MOSTLY SUNNY SKIES
WITH HIGHS AGAIN IN THE MIDDLE 30S TO MIDDLE 40S.
SOUTHERLY FLOW RETURNS TO THE AREA ON SATURDAY WITH THE NAM SHOWING
925MB TEMPERATURES WARMING INTO THE 5-6C RANGE. WITH SUNNY SKIES AND
DECENT MIXING...EXPECT HIGHS TO TOP OFF IN THE 50S.
FOR SATURDAY NIGHT...THE 84H NAM/ECMWF SHOWING AN AREA OF RAIN AHEAD
OF AN UPPER LOW MOVING INTO THE CENTRAL PLAINS SURGING NORTHWARD
TOWARD THE AREA. HAVE INCLUDED A 20-30 PERCENT CHANCE OF -RA ACROSS
MAINLY SOUTH OF I-90 TO ACCOUNT FOR THIS.
.LONG TERM...SUNDAY THROUGH WEDNESDAY
240 PM CST WED MAR 7 2012
THE 07.12Z GFS/ECMWF BOTH SHOWING THE UPPER LOW CONTINUING TO MOVE
NORTHEAST INTO THE AREA SUNDAY THROUGH SUNDAY NIGHT FOR A GOOD
CHANCE OF RAIN. THE MODELS THEN SHOW MID/UPPER LEVEL RIDGE BUILDING
ACROSS THE CENTRAL CONUS THROUGH THE REST OF THE PERIOD FOR A
WARMING TREND. AS FAR AS TEMPERATURES GO...TOOK A BLEND OF THE GFS
AND EUROPEAN WHICH YIELDED HIGHS IN THE 50S MONDAY...WARMING TO THE
LOWER TO MIDDLE 60S ON TUESDAY AND THE MIDDLE/UPPER 60S ON
WEDNESDAY. IF THE ECMWF PANS OUT...HIGHS COULD BE PUSHING WELL INTO
THE 70S. WILL BE KEEPING A CLOSE EYE ON THIS OVER THE NEXT COUPLE OF
DAYS.
&&
.AVIATION...THROUGH 18Z THURSDAY
1100 AM CST WED MAR 7 2012
A COLD FRONT WILL SWEEP EASTWARD THROUGH THE REGION THIS
AFTERNOON...WITH LATEST RUC13 AND HRRR MODELS PUSHING IT ACROSS KRST
NEAR 20Z AND KLSE AROUND 23Z. SOUTHERLY WINDS MOISTENING THE AIR
MASS...BUT MOSTLY VFR CONDITIONS AHEAD OF THE FRONT. POST FRONT SFC
OBS INDICATE MVFR/IFR CIGS. ALSO SOME -RA/DZ BEHIND THE
BOUNDARY...IN A REGION OF SLOPING FRONTOGENETIC LIFT. SOME SUB 2SM
VSBYS IN THIS AREA...MOSTLY WITH AREAS OF -DZ/BR. WILL ADD A TEMPO
GROUP FOR KRST FOR LOWER VSBYS...AND CONTINUE SOME IFR CIGS. THINK
THERE SHOULD BE SOME DIURNAL IMPROVEMENT POST FRONT...SO CONFIDENCE
NOT HIGH THAT THE LOWER CIGS/VSBYS WILL BE REALIZED FARTHER EAST.
THAT SAID OF COURSE...TRENDS WILL HAVE TO BE MONITORED AND UPDATES
MADE IF THESE CONDITIONS LOOK MORE LIKELY. CIGS SHOULD CLEAR LATER
TONIGHT AS THE LOW PRESSURE SYSTEM/COLD FRONT CONTINUE EAST...AND
HIGH PRESSURE BUILDS OVER THE SOUTHERN PLAINS.
BUFKIT SOUNDINGS SHOW A GOOD MIXED NEAR SFC LAYER THROUGH TONIGHT
AND INTO THURSDAY. EXPECT GUSTS TO CONTINUE AT KRST AS A
RESULT...ALTHOUGH VALLEY LOCATION OF KLSE AND DIRECTION OF WIND
SHOULD PREVENT MOST GUSTS. TIGHT PRESSURE GRADIENT AND MIXING UP TO
4 KFT WILL MAKE FOR WINDY/GUSTY THU.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
240 PM CST WED MAR 7 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DAS
LONG TERM....DAS
AVIATION...RIECK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1100 AM CST WED MAR 7 2012
.SHORT TERM...TODAY THROUGH FRIDAY NIGHT
310 AM CST WED MAR 7 2012
MAIN FORECAST CONCERNS ARE ON PRECIPITATION CHANCES TODAY INTO
TONIGHT AND TEMPERATURES THROUGH THE PERIOD.
LATEST SURFACE OBSERVATIONS SHOWED A COLD FRONT STRETCHING FROM
NORTH CENTRAL MINNESOTA SOUTHWEST INTO CENTRAL NEBRASKA.
THE COLD FRONT IS EXPECTED TO MOVE FROM WEST TO EAST ACROSS THE
FORECAST AREA THIS AFTERNOON. THE WARM SOUTHERLY FLOW WILL CONTINUE
ACROSS THE AREA THIS MORNING AHEAD OF THE FRONT. WITH VERY MILD
TEMPERATURES ALREADY IN PLACE ACROSS MUCH OF THE AREA THIS
MORNING...SHOULD HAVE NO PROBLEM WARMING INTO THE UPPER 50S TO LOWER
60S. ANOTHER CONCERN IS ON PLACEMENT OF PRECIPITATION AS THE FRONT
MOVES THROUGH. EARLY THIS MORNING...THE MOST OF THE CLOUD COVER WAS
POST FRONTAL WITH NO SIGNIFICANT PRECIPITATION BEING REPORTED.
HOWEVER...AS THE FRONT MOVES SOUTHEAST FRONTOGENESIS IS EXPECTED TO
INCREASE. THE FIRST BAND OF FRONTOGENESIS LOOKS TO SET UP IN THE
900-800 MB LEVEL. FORECAST SOUNDINGS SUPPORT LOW LEVEL SATURATION SO
SHOULD SEE THE DEVELOPMENT OF LIGHT RAIN ACROSS NORTHEAST
IOWA...SOUTHEAST MINNESOTA INTO WESTERN WISCONSIN THIS AFTERNOON.
THIS FRONTOGENESIS BAND APPEARS TO DEEPEN WITH TIME AS IT DRIFTS
SOUTHEAST INTO EXTREME NORTHEAST IOWA AND FAR SOUTHWEST WISCONSIN
LATE THIS AFTERNOON INTO THIS EVENING. SHOULD SEE THE RAIN BAND
BECOME MORE ORGANIZED AS IT MOVES SOUTHEAST DURING THE LATE
AFTERNOON INTO THE EVENING HOURS. EXTREME SOUTHWEST WISCONSIN MAY
PICK UP AROUND A QUARTER OF AN INCH OF RAINFALL OUT OF THIS SYSTEM
WITH 0.03 TO AROUND A TENTH OF INCH ELSEWHERE. PLAN ON FALLING
TEMPERATURES THIS AFTERNOON IN THE WAKE OF THE FRONT. THE RAIN IS
EXPECTED TO MOVE SOUTHEAST OF THE FORECAST AREA LATE THIS EVENING.
DEPENDING ON HOW QUICKLY THE COLDER AIR MOVES IN...WE COULD SEE
A BRIEF PERIOD OF LIGHT SNOW BEFORE THE PRECIPITATION ENDS. LOOK
FOR LOW TEMPERATURES TO RANGE FROM THE LOWER 20S ACROSS PORTIONS
OF NORTHEAST IOWA THROUGH NORTH CENTRAL WISCONSIN TO THE UPPER 20S
TO LOWER 30S ACROSS FAR SOUTHWEST WISCONSIN.
HIGH PRESSURE WILL EDGE INTO THE AREA LATE TONIGHT INTO THURSDAY.
850 MB TEMPERATURES WILL FALL 10 DEGREES FROM THIS AFTERNOON INTO
THURSDAY...WITH 850 MB TEMPS RANDING FROM -10 C ACROSS NORTH
CENTRAL WISCONSIN TO -5 C ACROSS NORTHEAST IOWA. AN UPPER LEVEL
TROUGH WILL SLIDE THROUGH THURSDAY AFTERNOON WITH THE POTENTIAL TO
BRING SOME CUMULUS CLOUDS TO THE AREA. PLAN ON HIGH TEMPERATURES
RANGING FROM THE UPPER 30S ACROSS NORTH CENTRAL WISCONSIN TO THE
LOWER 40S ACROSS NORTHEAST IOWA UNDER PARTLY SUNNY SKIES. FORECAST
SOUNDINGS ARE SHOWING THE POTENTIAL FOR A FEW RAIN/SNOW SHOWERS ON
THURSDAY WITH STEEP LAPS RATES IN PLACE. HOWEVER...LOW LEVEL
MOISTURE IS LACKING WITH TEMPERATURE/DEW POINT SPREADS OF 10
DEGREES ACROSS PORTIONS OF SOUTHEAST MINNESOTA INTO FAR SOUTHWEST
WISCONSIN. NORTH OF INTERSTATE 94...THERE MAY BE ENOUGH LOW LEVEL
MOISTURE TO PRODUCE VERTICALLY DEVELOPED CUMULUS TO PRODUCE LIGHT
RAIN OR SNOW SHOWERS. CONFIDENCE LOW ON THIS OCCURRING GIVEN HOW
DRY THE AIRMASS IS. WILL INCREASE CLOUD COVER ACROSS THESE AREAS
ON THURSDAY TO ACCOUNT FOR SHALLOW CUMULUS DEVELOPMENT. IT WILL BE
RATHER BREEZY ON THURSDAY WITH SURFACE LOW PRESSURE PASSING JUST
NORTH OF LAKE SUPERIOR AND HIGH PRESSURE ACROSS THE
DAKOTAS...PRODUCING A TIGHT PRESSURE GRADIENT ACROSS THE FORECAST
AREA. LOOK FOR WEST NORTHWEST WINDS OF 15 TO 25 MPH WITH GUSTS TO
AROUND 35 MPH. PLAN ON DECREASING CLOUDS THURSDAY EVENING AS
SURFACE COOLING COMMENCES. SURFACE HIGH PRESSURE WILL MOVE OVER
THE REGION ON FRIDAY PROVIDING SUNNY SKIES. LOOK FOR HIGH
TEMPERATURES TO RANGE FROM THE MID 30S ACROSS NORTH CENTRAL
WISCONSIN TO THE LOWER 40S ACROSS NORTHEAST IOWA. UPPER LEVEL
RIDGING IS EXPECTED TO PUSH INTO THE UPPER MISSISSIPPI RIVER
VALLEY FRIDAY NIGHT FROM THE NORTHERN PLAINS...WITH 850 MB
TEMPERATURES WARMING TO AROUND +6 C BY EARLY SATURDAY MORNING.
.LONG TERM...SATURDAY THROUGH TUESDAY
310 AM CST WED MAR 7 2012
UPPER LEVEL RIDGING IS EXPECTED ACROSS THE UPPER MISSISSIPPI RIVER
VALLEY ON SATURDAY AS AN UPPER LOW OVER THE FOUR CORNERS REGION
MEANDERS INTO THE CENTRAL PLAINS. PLAN ON HIGH TEMPERATURES ON
SATURDAY RANGING FROM THE UPPER 40S ACROSS NORTH CENTRAL WISCONSIN
TO THE LOWER 50S ACROSS WESTERN WISCONSIN INTO NORTHEAST IOWA.
07.00 MEDIUM RANGE MODELS CONTINUE TO SHOW DIFFERING SOLUTIONS
REGARDING THE THE EVOLUTION AND MOVEMENT OF THE FOUR CORNERS LOW
SATURDAY NIGHT INTO SUNDAY. THE ECMWF TAKES THE UPPER LOW INTO
EASTERN NEBRASKA SUNDAY AFTERNOON AND INTO THE FORECAST AREA
SUNDAY NIGHT. THE GFS IS A LITTLE FASTER AND BRINGS THE UPPER LOW
INTO CENTRAL IOWA SUNDAY AFTERNOON AND JUST BRUSHES SOUTHERN
PORTIONS OF THE FORECAST AREA SUNDAY NIGHT....WITH A SECOND UPPER
LOW DIVING SOUTH ACROSS SOUTHERN TEXAS. THE GEM LATCHES ONTO THE
SOUTHERN LOW SOLUTION AND TAKES THE LOW INTO TEXAS...LIFTING IT
INTO THE UPPER MISSISSIPPI RIVER VALLEY REGION SUNDAY NIGHT INTO
MONDAY. GIVEN THE SPREAD IN POTENTIAL SOLUTIONS WILL MAINTAIN A
MODEL CONSENSUS BLEND APPROACH SUNDAY INTO MONDAY. PLAN ON A
CHANCE OF RAIN ACROSS THE ENTIRE AREA SUNDAY INTO SUNDAY NIGHT
BEFORE THE LOW FINALLY EXITS THE AREA. WARM TEMPERATURES WILL
PERSIST MONDAY INTO TUESDAY WITH HIGHS IN THE 50S TO AROUND 60.
&&
.AVIATION...
1100 AM CST WED MAR 7 2012
A COLD FRONT WILL SWEEP EASTWARD THROUGH THE REGION THIS
AFTERNOON...WITH LATEST RUC13 AND HRRR MODELS PUSHING IT ACROSS KRST
NEAR 20Z AND KLSE AROUND 23Z. SOUTHERLY WINDS MOISTENING THE AIR
MASS...BUT MOSTLY VFR CONDITIONS AHEAD OF THE FRONT. POST FRONT SFC
OBS INDICATE MVFR/IFR CIGS. ALSO SOME -RA/DZ BEHIND THE
BOUNDARY...IN A REGION OF SLOPING FRONTOGENETIC LIFT. SOME SUB 2SM
VSBYS IN THIS AREA...MOSTLY WITH AREAS OF -DZ/BR. WILL ADD A TEMPO
GROUP FOR KRST FOR LOWER VSBYS...AND CONTINUE SOME IFR CIGS. THINK
THERE SHOULD BE SOME DIURNAL IMPROVEMENT POST FRONT...SO CONFIDENCE
NOT HIGH THAT THE LOWER CIGS/VSBYS WILL BE REALIZED FARTHER EAST.
THAT SAID OF COURSE...TRENDS WILL HAVE TO BE MONITORED AND UPDATES
MADE IF THESE CONDITIONS LOOK MORE LIKELY. CIGS SHOULD CLEAR LATER
TONIGHT AS THE LOW PRESSURE SYSTEM/COLD FRONT CONTINUE EAST...AND
HIGH PRESSURE BUILDS OVER THE SOUTHERN PLAINS.
BUFKIT SOUNDINGS SHOW A GOOD MIXED NEAR SFC LAYER THROUGH TONIGHT
AND INTO THURSDAY. EXPECT GUSTS TO CONTINUE AT KRST AS A
RESULT...ALTHOUGH VALLEY LOCATION OF KLSE AND DIRECTION OF WIND
SHOULD PREVENT MOST GUSTS. TIGHT PRESSURE GRADIENT AND MIXING UP TO
4 KFT WILL MAKE FOR WINDY/GUSTY THU.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
310 AM CST WED MAR 7 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...WETENKAMP
LONG TERM....WETENKAMP
AVIATION.....RIECK