Forecast Discussions mentioning any of
"HRRR" "RR" "RUC13" "RUC" received at GSD on 02/02/12
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
403 AM EST TUE JAN 31 2012
.SHORT TERM...TODAY THROUGH THURSDAY...
EARLY THIS MORNING...HIGH PRESSURE RIDGE STILL HANGING ON WITH DRY
ENOUGH AIRMASS TO ALLOW FOR TEMPS IN THE 30S ACROSS INLD SE GA AND
INLD NE FL WITH SOME PATCHY FROST ACROSS SOME LOCATIONS. A FEW WISPS
OF CIRRUS JUST STARTING TO PUSH INTO THE REGION. NO DOUBT SOME
PATCHY SMOKE NEAR WILDFIRE LOCATIONS IN INLD NE FL...BUT NOT ENOUGH
CONFIDENCE TO ISSUE ANY SPECIFIC DENSE SMOKE ADVISORY AT THIS
TIME...WILL CONTINUE TO MONITOR FOR POSSIBLE ADVISORY AROUND SUNRISE
OR ISSUE SPS TO COVER ANY LOCALIZED SMOKE ISSUES.
TODAY...HIGH CLOUDS TO OVERSPREAD THE REGION WITH LLVL FLOW BECOMING
SOUTHEAST AND TEMPS WARMING INTO THE LOWER/MID 70S INLAND AND 60S
ALONG THE COAST.
TONIGHT...CLOUDS CONTINUE TO INCREASE AHEAD OF NEXT SYSTEM WITH MUCH
MILDER OVERNIGHT LOWS IN THE 40S/50S. PATCHY FOG/SMOKE POSSIBLE
DURING THE LATE NIGHT HOURS.
WEDNESDAY...MODELS STILL IN GOOD AGREEMENT WITH PCPN BREAKING OUT
AHEAD OF DEVELOPING WEAK LOW IN THE NORTHERN GOMEX AND SPREADING
INTO THE REGION WHICH APPEARS TO BE MAINLY LIGHT AT THIS TIME. MORE
CLOUD COVER HAS TRENDED MAX TEMP FORECAST SLIGHTLY DOWNWARD...MAINLY
IN THE LOWER/MID 70S.
WED NIGHT...GOOD ISENTROPIC LIFT AHEAD OF SYSTEM AND RR QUAD OF
UPPER LEVEL JET WILL ENHANCE RAINFALL CHANCES WITH LIKELY POPS
ACROSS SE GA AND AT LEAST CHANCE POPS FOR NE FL. RAINFALL AMOUNTS OF
A TENTH TO A QUARTER OF AN INCH ARE EXPECTED.
THURSDAY...AS WEAK LOW TRACKS ACROSS THE FORECAST AREA...SCATTERED
TO NUMEROUS SHOWERS IN THE MORNING WILL SLOWLY DECREASE IN COVERAGE
DURING THE AFTERNOON HOURS. MAX TEMPS EXPECTED INTO THE 70S...BUT
WILL DEPEND ON HOW FAST LOW TRACKS ACRS THE REGION AND AMOUNT OF
PARTIAL CLEARING EXPECTED DURING THE AFTERNOON HOURS.
.LONG TERM...FRIDAY THROUGH MONDAY...
FRIDAY...WITH TRAILING FRONT STALLED ACROSS CNTRL FL IN THE
MORNING...ONLY A SLIGHT CHANCE OF SHOWERS BY THE AFTERNOON/EVENING
AS ISENTROPIC LIFT BEGINS ALONG FRONTAL BOUNDARY AS IT LIFTS TO THE
NORTH. MAX TEMPS STILL ABOVE NORMAL IN THE LOWER TO MID 70S.
SATURDAY...FRONT SHOULD LIFT NORTH INTO MIDDLE/SOUTH GEORGIA REGION
WITH SOME SCTD SHOWER/ISOLD TSTM ACTIVITY POSSIBLE IN THE WARM
SECTOR ACROSS THE FORECAST AREA. MAX TEMPS WELL INTO THE 70S BUT
WITH UNCERTAINTY IN SCENARIO WILL KEEP POPS IN THE 20-30% RANGE.
SUNDAY...LOW PRESSURE DEVELOPMENT NORTH OF THE REGION SHOULD DRAG
FRONTAL BOUNDARY INTO THE REGION WITH SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS POSSIBLE AREA-WIDE. AGAIN CONFIDENCE/TIMING STILL
LOW/MODERATE AT THIS TIME SO HAVE KEPT POPS AROUND 30% ALTHOUGH HIGH
ENOUGH CONFIDENCE IN WARMER THAN NORMAL TEMPS CONTINUING IN THE 70S.
MONDAY...TRAILING COLD FRONT SHOULD SLOWLY PUSH THROUGH THE FORECAST
AREA AND MAY END UP BEING A DRY DAY WITH LINGERING CLOUDS BUT FOR
NOW HAVE KEPT JUST A SLIGHT CHANCE OF SHOWERS IN THE FORECAST AND
HAVE STAYED CLOSER TO THE SLIGHTLY WARMER MEX GUIDANCE WITH HIGHS
70-75 BUT WILL DEPEND ON FRONTAL TIMING.
&&
.AVIATION...OCNL MVFR VSBY IN SMOKE AT GNV TIL 12Z. OTHERWISE
PREVAILING VFR.
&&
.MARINE...
NO HEADLINES THROUGH THE SHORT TERM AS RIDGE REMAINS NORTH OF THE
WATERS. NEXT INCREASE OF WINDS WILL OCCUR ON FRIDAY IN THE WAKE OF
DEPARTING LOW PRESSURE AND HIGH PRESSURE RIDGE BUILDING IN FROM THE
NORTH WITH NE/E WINDS INCREASING TO 20 KNOTS WITH SEAS AT 5-7 FT
POSSIBLE.
RIP CURRENTS: LOW RISK CONTINUES AS ONSHORE FLOW REMAINS ON THE WEAK
SIDE AND NO SIGNIFICANT SWELLS WITH 2-3 FT BREAKERS POSSIBLE.
&&
.FIRE WEATHER...
BOUNDARY LAYER WILL CONTINUE TO MOISTEN TODAY AND RH VALUES WILL
REMAIN ABOVE CRITICAL LEVELS ACROSS NORTHEAST FLORIDA. MIN RH VALUES
WILL DROP INTO THE 30-35% RANGE ACROSS INLD SE GA...BUT WINDS WILL
REMAIN LESS THAN 10 MPH...SO NO HEADLINES ARE EXPECTED.
&&
.PRELIMINARY POINT TEMPS/POPS...
AMG 72 48 70 53 / 0 10 30 60
SSI 67 55 66 57 / 0 10 20 50
JAX 71 50 72 55 / 0 10 20 50
SGJ 69 54 70 57 / 0 10 10 40
GNV 74 50 73 55 / 0 10 20 40
OCF 77 52 76 57 / 0 10 10 30
&&
.JAX WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GA...NONE.
AM...NONE.
&&
$$
HESS/PETERSON
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
216 PM CST TUE JAN 31 2012
.DISCUSSION...
1054 AM CST
FOR MORNING UPDATE...
SOME MINOR TWEAKS TO GOING TEMP/SKY AND WX/POP GRIDS...THOUGH
FORECAST REMAINS LARGELY ON TRACK.
LOW PRESSURE POISED TO MOVE EAST ACROSS THE UPPER PENINSULA OF
MICHIGAN THIS AFTERNOON IN RESPONSE TO RATHER PRONOUNCED MID LEVEL
SHORT WAVE TROUGH PROPAGATING ACROSS THE UPPER MIDWEST. WARM SECTOR
SOUTH OF THE LOW ALREADY WARMING INTO THE LOW-MID 50S ACROSS THE CWA
AS OF 16Z. PERUSAL OF UPSTREAM SOUNDINGS AND LATEST MODEL LOW LEVEL
THERMAL PROGS CONTINUE TO SUGGEST MAX TEMPS ACROSS THE FORECAST AREA
POTENTIALLY RANGING FROM THE UPPER 50S NORTH TO THE MID 60S SOUTH...
HOWEVER GOES VISIBLE SATELLITE IMAGERY DOES DEPICT DEVELOPMENT OF
SOME STRATUS/STRATO CU ACROSS MO/IL IN REGION OF LOW LEVEL MOIST
ADVECTION AHEAD OF APPROACHING SHORT WAVE AND SURFACE TROUGH/COLD
FRONT. THIS CONTINUES TO MAKE FOR SOMEWHAT TRICKY AFTERNOON TEMP
FORECAST...WITH SOME VARIABLE COVERAGE IN OVERCAST CONDITIONS BUT AN
OVERALL INCREASE IN CLOUDINESS THROUGH THE AFTERNOON. HAVE TWEAKED
TEMPS UP JUST A LITTLE IN SOME SPOTS BASED ON TRENDS AND EXTRAPOLATED
NEAR TERM CLOUD TRENDS...BUT CANT ARGUE TOO MUCH WITH GOING
FORECAST.
IN ADDITION...POTENTIAL FOR DRIZZLE/SPRINKLES NOT LOOKING VERY
IMPRESSIVE AT THIS TIME...THOUGH GUIDANCE CONTINUES TO SUGGEST SOME
INCREASE IN POTENTIAL FOR SOME PATCHY LIGHT PRECIP ACROSS MAINLY THE
SOUTHEAST CWA VERY LATE THIS AFTERNOON/EVENING. HAVE ADJUSTED
LOCATION/COVERAGE ACCORDINGLY.
RATZER
//PREV DISCUSSION...
317 AM CST
THE ATTENTION ON THIS FORECAST WAS PRIMARILY DIRECTED TO
TEMPERATURES...WITH AN EMPHASIS ON TODAY AS NEAR RECORD TO RECORD
WARMTH IS ON PAR AGAIN FOR THE AREA. QUITE A DIFFERENCE FROM ONE
YEAR AGO TODAY...WHICH SAW THE AREA PREPARING FOR THE THIRD
LARGEST SNOWSTORM ON RECORD. AN ADDITIONAL CHALLENGE IN THE
FORECAST IS THAT BOTH WEDNESDAY AND THURSDAY ALSO ARE APPEARING
LIKELY TO BE WARMER THAN INITIALLY THOUGHT.
TEMPERATURES ARE STARTING NEARLY 30 DEGREES ABOVE NORMAL THIS
FINAL DAY OF JANUARY...WHICH IS FITTING FOR THIS MONTH THAT IS
AVERAGING 5 TO 6 DEGREES ABOVE NORMAL. SOUTHERLY WINDS AND
INCREASING LOW-LEVEL MOISTURE THROUGHOUT LAST NIGHT INTO THIS
MORNING HAVE AIDED THESE MILD READINGS. THE ANTICIPATED
STRATUS/STRATOCU IS DEVELOPING QUICKLY NORTHEAST FROM THE SOUTHERN
PLAINS/OZARKS EARLY THIS MORNING...LINING UP WELL WITH MODEL
DIAGNOSTIC SOLUTIONS OF MOISTURE TRANSPORT AND CONVERGENCE IN THE
LOW LEVELS /ROUGHLY 850-925MB/.
EVEN AHEAD OF THESE LOW CLOUDS...MODEL GUIDANCE CONTINUES TO SHOW
BOTH A TOO MOIST AND COOL BIAS IN THE LOW-LEVELS...SOME LIKELY DUE
TO FALSE SNOW COVER AND/OR TOO COLD OF GROUND COVER. JUST THE
31.00 GFS AND NAMELY THE NAM SOUNDINGS ACROSS THE AREA REVEALED
THIS BIAS ALMOST IMMEDIATELY AFTER THEIR INITIALIZATION HOURS. SO
HAVE GUIDED MORE ON ABSOLUTE MOISTURE VALUES AND SATURATION NEAR
THE TOP OF THE ADAPTED MIXED-LAYER LATER THIS MORNING /~4000 FT/
FOR CLOUD INDICATIONS. THE MOISTURE CONVERGENCE FORECAST FROM THE
RUC AND NAM LINE UP WELL FROM SOUTHEAST IA INTO NORTHERN IL AND
EXPECT THE CLOUDS TO EXPAND INTO THAT AREA DURING THE LATE
MORNING. RUC PARCEL TRAJECTORIES WOULD INDICATE NEAR A 12 PM
ARRIVAL IN CHICAGO BASED ON CURRENT PLACEMENT OF THE LOW
CLOUDS...BUT SOME LEAD SATURATION MAY CAUSE IT TO BE A LITTLE
QUICKER. THE STRATUS PLUME AND HOW QUICKLY IT MOVES IN WILL LIKELY
IMPACT TEMPERATURES A FEW DEGREES.
AS FOR THOSE TEMPERATURES TODAY...LOCAL ANALYSIS HERE HAS SHOWN
THAT BIAS-CORRECTED GUIDANCE IS WORKING VERY WELL IN THESE VERY
MILD STRETCHES THIS WINTER...PARTICULARLY THE GEM AND THE EC. HAVE
BLENDED OUR GOING FORECAST HEAVILY TOWARDS THESE SOLUTIONS...AND
EVEN ADJUSTED UP FROM THERE IN SOME AREAS. WHILE THE CLOUDS WILL
EXPAND IN...CONTINUED LOW-LEVEL WARM ADVECTION WILL LIKELY
SUPPORT INCREASING SURFACE TEMPERATURES INTO THE
AFTERNOON...ALBEIT AT A SLOWER RATE. SO HAVE SOME QUICK MORNING
WARMING FORECAST FROM THE HIGH STARTING POINT VALUES...AND THEN
GRADUAL INCREASE THIS AFTERNOON. THIS APPROACH YIELDS REMARKABLY
MILD UPPER 50S TO LOWER 60 DEGREE READINGS BEING LIKELY IN SEVERAL
AREAS. EVEN MID 60S COULD BE TOUCHED IN THE EASTERN HALF OF THE
AREA IF THE RATE OF WARMING AFTER THE CLOUDS ARRIVE IS HIGHER THAN
INDICATED. PLEASE SEE THE CLIMATE SECTION BELOW FOR RECORD
INFORMATION.
AS FOR PRECIPITATION CHANCES THIS AFTERNOON INTO TONIGHT...THE
DEPTH OF THE CLOUDS INCREASE QUICKLY LATE THIS AFTERNOON INTO THE
EVENING. MARGINAL SATURATED ISENTROPIC ASCENT AND CONVERGENCE
AHEAD OF A COLD FRONT MOVING THROUGH...MAY OFFER SPORADIC LIGHT
RAIN OR DRIZZLE IN THE SOUTHEAST HALF OF THE FORECAST AREA DURING
THE LATE AFTERNOON AND EVENING. THE LIGHT RAIN MAY ACTUALLY BE
MORE SHOWERY...BUT LIMITED FORCING WILL PREVENT ANYTHING
APPRECIABLE.
WEDNESDAY AND THURSDAY...WHILE LOW-LEVEL TEMPERATURES ARE FORECAST
TO COOL DURING THIS PERIOD...THEY ARE STILL ON THE WARMER THAN
NORMAL SIDE. THE LACK OF SNOW COVER TOO SHOULD AID IN THE WARMER
BIAS-CORRECTED GUIDANCE BEING MORE ON TRACK. CLOUDS ALSO LOOK
LIMITED...ALTHOUGH CONFIDENCE IS CURRENTLY LOW ON WEDNESDAY
MORNING WITH A SOMEWHAT LIMITED SURGE BEHIND THIS FRONT MEANING
LINGERING STRATUS IS POSSIBLE. IF NOT THOUGH...TEMPERATURES
GETTING TO 50 ON WEDNESDAY SEEM PROBABLE...AND THEN WELL INTO THE
40S ON THURSDAY. RIDGING SHOULD ALLOW FOR ONLY CIRRUS BY THURSDAY.
LATE THIS WEEK INTO THE WEEKEND...THE PROGRESSIVE WESTERLY PATTERN
IS EXPECTED TO SLOW DOWN WITH A CUT OFF LOW AND A GENERAL BLOCKING
PATTERN DEVELOPING TO OUR WEST. DETAILS HAVE VARIED
SIGNIFICANTLY...BUT A CLEAR TREND IN THE GUIDANCE IS SLOWER WITH
PROGRESSING FORCING FOR PRECIPITATION EAST INTO OUR AREA. GIVEN
THAT PATTERN...THAT SEEMS REASONABLE AND HAVE ADJUSTED THE BLENDED
GUIDANCE FORECAST THAT WAY. THE SLOWER 31.00 EC WAS FOLLOWED
CLOSELY FOR DETAILS. SOME FORM OF INVERTED TROUGH OR WEAK SURFACE
LOW IS LIKELY TO DEVELOP AS THE CLOSED UPPER CIRCULATION WORKS
EAST...AND SUCH A FEATURE WOULD ALSO NOT FAVOR PRECIP FAR TO ITS
EAST. SO ONLY HAVE SMALL CHANCES DURING THE WEEKEND...WITH
FORECAST SOUNDINGS AND GENERAL THICKNESSES SLIGHTLY MORE
SUPPORTIVE OF RAIN THAN SNOW IF PRECIP OCCURS. IT IS STILL
FAVORED THAT NO PRECIPITATION WILL OCCUR THIS WEEKEND...ESPECIALLY
IF THE EC SOUTHERN TRACK OF THE CLOSED LOW WERE TO COME TO
FRUITION.
&&
.CLIMATE...
THE RECORD HIGH TODAY FOR CHICAGO IS 65 IN 1989. THE HIGH
TEMPERATURE IS MOST LIKELY TO BE 3 TO 7 DEGREES SHY OF THIS...BUT
IT COULD END UP GETTING VERY CLOSE. THE GOING FORECAST IS FOR THIS
TO BE THE WARMEST DAY THIS METEOROLOGICAL WINTER SO FAR. THIS WILL
BE THE TENTH DAY IN AT LEAST THE 50S SINCE DECEMBER 1ST /BASICALLY
ONE DAY A WEEK THIS WINTER SO FAR/. AS FOR ROCKFORD THE RECORD
HIGH IS 63 ALSO IN 1989. THE HIGH TEMPERATURE IS EXPECTED TO FALL
SEVERAL DEGREES SHORT...BUT CONFIDENCE IS LOWER AT ROCKFORD
DEPENDING ON HOW THE STRATUS EVOLVES IN /IT MAY REMAIN SOUTH OF
ROCKFORD/. THIS WILL BE THE NINTH DAY IN AT LEAST THE 50S THIS
METEOROLOGICAL WINTER AT ROCKFORD.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* MVFR CIGS THROUGH EARLY THIS EVENING.
* SWLY GUSTS TO 25KT DROPPING OFF LATE THIS AFTERNOON.
* SLIGHT CHANCE OF VIS DROPPING TO MVFR IN HZ/BR DURG EARLY
MORNING HOURS.
LENNING
//DISCUSSION...UPDATED 18Z...
GUSTY SWLY WINDS WILL CONTINUE INTO THE AFTERNOON AHEAD OF A WEAK
COLD FRONT MOVING INTO ERN IOWA. A PLUME OF LOW LEVEL MOISTURE
AHEAD OF THE FRONT HAS ALLOWED THE FORMATION OF A BKN STRATOCU
DECK EXTENDING FROM NRN MO TO NRN IL/IN. BASES OF THE CLOUD DECK
SHOULD STAY AT ARND 2.5KFT. AT ISSUANCE TIME...ORD/DPA/GYY WE JUST
TO THE NORTH OF THE BKN MVFR CIGS...AND ANTICIPATE THAT THE
COVERAGE SHOULD INCREASE TO BKN WITHIN THE HOUR OF ISSUANCE.
THE FRONT WILL STEADILY PUSH EWD THIS AFTERNOON...KEEPING WINDS
BRISK AND GUSTY UNTIL THE ASSOCIATED TROUGH CROSSES THE AREA LATE
THIS AFTERNOON AND EARLY THIS EVENING...RELAXING THE PRESSURE
GRADIENT OVER THE REGION. FOLLOWING THE FROPA...HIGH PRESSURE WILL
SPREAD ACROSS THE CENTRAL PLAINS AND INTO THE MIDWEST...ALLOWING
WINDS TO QUICKLY DROP OFF. DRIER AIR BEHIND THE FRONT SHOULD BRING
QUICKLY CLEARING SKIES. THE MAIN CONCERN FOR THE OVERNIGHT HOURS
WILL SHIFT TO VISIBILITY. SOME OF THE NUMERICAL GUIDANCE IS
INDICATING A CHANCE FOR VISBY REDUCTION TO MVFR AS SKIES CLEAR AND
WINDS DECREASE. THE ONE LIMITING FACTOR FOR VISIBILITY WILL BE LOW
LEVEL MOISTURE. THE AIRMASS BEHIND THE FRONT WILL BE RATHER DRY
AND IT IS UNCERTAIN THAT THERE WILL BE ENOUGH COOLING TO DROP THE
TEMPERATURE CLOSE ENOUGH TO THE DEWPOINT TO LEAD TO BR FORMATION.
SO...HAVE ONLY GONE WITH 6SM HZ FOR THE EARLY MORNING HOURS TO
BEGIN A TREND AND WILL MONITOR CONDITIONS CLOSELY TO SEE IF A
LOWER VISIBILITY FORECAST WILL BE WARRANTED FOR THE MORNING RUSH
HOURS. OTHERWISE...TOMORROW IS SHAPING UP TO BE A QUIET DAY WITH
NO OPERATIONALLY SIGNIFICANT WEATHER CONCERNS.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM CONFIDENCE ON CEILING TRENDS. UPSTREAM OBS MAY BE
SOMEWHAT MORE OPTIMISTIC THAN TRENDS IN LATEST TAFS. THIS WOULD
RESULT IN SHORTER PERIOD OF MVFR.
* MEDIUM CONFIDENCE IN GUST SPEEDS AND TIME THAT THEY WOULD BE
DIMINISHING THIS AFTERNOON.
LENNING
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
* WEDNESDAY NIGHT THROUGH FRIDAY...VFR
* SATURDAY AND SUNDAY...SLIGHT CHANCE OF RAIN OR SNOW
* MONDAY...VFR
SHEA
&&
.MARINE...
216 PM CST
LOW PRESSURE ACROSS NORTH CENTRAL WI AND FAR SOUTH CENTRAL LAKE
SUPERIOR EARLY THIS AFTERNOON CONTINUES TO LIFT A WARM FRONT
NORTHWARD ACROSS THE NORTHERN PORTION OF LAKE MICHIGAN. TO THE SOUTH
OF THIS FRONT WINDS ARE GUSTY UP TO 30 KT AT TIMES FROM THE
SOUTHWEST. THIS LOW WILL CONTINUE EASTWARD TO THE UPPER PENINSULA OF
MICHIGAN LATER THIS AFTERNOON AND EVENING. AS THIS HAPPENS...A COLD
FRONT WILL MOVE ACROSS LAKE MICHIGAN BY MID TO LATE EVENING. THIS
WILL PRODUCE A WIND SHIFT TO THE WEST NORTHWEST LATER THIS EVENING
AND OVERNIGHT. THESE WINDS WILL GRADUALLY ABATE ON WEDNESDAY AS A
BROAD AREA OF HIGH PRESSURE BUILDS IN FROM THE WEST. THIS BROAD HIGH
LOOKS TO PRODUCE A PERIOD OF LIGHT AND VARIABLE WINDS ACROSS LAKE
MICHIGAN ON THURSDAY INTO FRIDAY.
AS WE HEAD INTO THE COMING WEEKEND A RATHER COMPLEX WEATHER PATTERN
IS FORECAST TO OCCUR ACROSS THE WESTERN AND CENTRAL CONUS. THIS
PATTERN WILL LIKELY LEAD TO THE DEVELOPMENT OF LOW PRESSURE ACROSS
THE PLAINS. HOWEVER...DUE TO THE COMPLEX NATURE OF THE EVOLVING
UPPER LEVEL WEATHER PATTERN DURING THIS TIME...UNCERTAINTY ON THE
TIMING AND TRACK OF THIS LOW INTO THIS COMING WEEKEND REMAINS HIGHER
THAN AVERAGE. ULTIMATELY...THIS WILL HAVE LARGE IMPACTS ON THE WIND
SPEEDS AND DIRECTIONS ACROSS THE LAKE THIS WEEKEND INTO EARLY NEXT
WEEK.
KJB
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 10 PM TUESDAY.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
214 PM CST TUE JAN 31 2012
.DISCUSSION...
1054 AM CST
FOR MORNING UPDATE...
SOME MINOR TWEAKS TO GOING TEMP/SKY AND WX/POP GRIDS...THOUGH
FORECAST REMAINS LARGELY ON TRACK.
LOW PRESSURE POISED TO MOVE EAST ACROSS THE UPPER PENINSULA OF
MICHIGAN THIS AFTERNOON IN RESPONSE TO RATHER PRONOUNCED MID LEVEL
SHORT WAVE TROUGH PROPAGATING ACROSS THE UPPER MIDWEST. WARM SECTOR
SOUTH OF THE LOW ALREADY WARMING INTO THE LOW-MID 50S ACROSS THE CWA
AS OF 16Z. PERUSAL OF UPSTREAM SOUNDINGS AND LATEST MODEL LOW LEVEL
THERMAL PROGS CONTINUE TO SUGGEST MAX TEMPS ACROSS THE FORECAST AREA
POTENTIALLY RANGING FROM THE UPPER 50S NORTH TO THE MID 60S SOUTH...
HOWEVER GOES VISIBLE SATELLITE IMAGERY DOES DEPICT DEVELOPMENT OF
SOME STRATUS/STRATO CU ACROSS MO/IL IN REGION OF LOW LEVEL MOIST
ADVECTION AHEAD OF APPROACHING SHORT WAVE AND SURFACE TROUGH/COLD
FRONT. THIS CONTINUES TO MAKE FOR SOMEWHAT TRICKY AFTERNOON TEMP
FORECAST...WITH SOME VARIABLE COVERAGE IN OVERCAST CONDITIONS BUT AN
OVERALL INCREASE IN CLOUDINESS THROUGH THE AFTERNOON. HAVE TWEAKED
TEMPS UP JUST A LITTLE IN SOME SPOTS BASED ON TRENDS AND EXTRAPOLATED
NEAR TERM CLOUD TRENDS...BUT CANT ARGUE TOO MUCH WITH GOING
FORECAST.
IN ADDITION...POTENTIAL FOR DRIZZLE/SPRINKLES NOT LOOKING VERY
IMPRESSIVE AT THIS TIME...THOUGH GUIDANCE CONTINUES TO SUGGEST SOME
INCREASE IN POTENTIAL FOR SOME PATCHY LIGHT PRECIP ACROSS MAINLY THE
SOUTHEAST CWA VERY LATE THIS AFTERNOON/EVENING. HAVE ADJUSTED
LOCATION/COVERAGE ACCORDINGLY.
RATZER
//PREV DISCUSSION...
317 AM CST
THE ATTENTION ON THIS FORECAST WAS PRIMARILY DIRECTED TO
TEMPERATURES...WITH AN EMPHASIS ON TODAY AS NEAR RECORD TO RECORD
WARMTH IS ON PAR AGAIN FOR THE AREA. QUITE A DIFFERENCE FROM ONE
YEAR AGO TODAY...WHICH SAW THE AREA PREPARING FOR THE THIRD
LARGEST SNOWSTORM ON RECORD. AN ADDITIONAL CHALLENGE IN THE
FORECAST IS THAT BOTH WEDNESDAY AND THURSDAY ALSO ARE APPEARING
LIKELY TO BE WARMER THAN INITIALLY THOUGHT.
TEMPERATURES ARE STARTING NEARLY 30 DEGREES ABOVE NORMAL THIS
FINAL DAY OF JANUARY...WHICH IS FITTING FOR THIS MONTH THAT IS
AVERAGING 5 TO 6 DEGREES ABOVE NORMAL. SOUTHERLY WINDS AND
INCREASING LOW-LEVEL MOISTURE THROUGHOUT LAST NIGHT INTO THIS
MORNING HAVE AIDED THESE MILD READINGS. THE ANTICIPATED
STRATUS/STRATOCU IS DEVELOPING QUICKLY NORTHEAST FROM THE SOUTHERN
PLAINS/OZARKS EARLY THIS MORNING...LINING UP WELL WITH MODEL
DIAGNOSTIC SOLUTIONS OF MOISTURE TRANSPORT AND CONVERGENCE IN THE
LOW LEVELS /ROUGHLY 850-925MB/.
EVEN AHEAD OF THESE LOW CLOUDS...MODEL GUIDANCE CONTINUES TO SHOW
BOTH A TOO MOIST AND COOL BIAS IN THE LOW-LEVELS...SOME LIKELY DUE
TO FALSE SNOW COVER AND/OR TOO COLD OF GROUND COVER. JUST THE
31.00 GFS AND NAMELY THE NAM SOUNDINGS ACROSS THE AREA REVEALED
THIS BIAS ALMOST IMMEDIATELY AFTER THEIR INITIALIZATION HOURS. SO
HAVE GUIDED MORE ON ABSOLUTE MOISTURE VALUES AND SATURATION NEAR
THE TOP OF THE ADAPTED MIXED-LAYER LATER THIS MORNING /~4000 FT/
FOR CLOUD INDICATIONS. THE MOISTURE CONVERGENCE FORECAST FROM THE
RUC AND NAM LINE UP WELL FROM SOUTHEAST IA INTO NORTHERN IL AND
EXPECT THE CLOUDS TO EXPAND INTO THAT AREA DURING THE LATE
MORNING. RUC PARCEL TRAJECTORIES WOULD INDICATE NEAR A 12 PM
ARRIVAL IN CHICAGO BASED ON CURRENT PLACEMENT OF THE LOW
CLOUDS...BUT SOME LEAD SATURATION MAY CAUSE IT TO BE A LITTLE
QUICKER. THE STRATUS PLUME AND HOW QUICKLY IT MOVES IN WILL LIKELY
IMPACT TEMPERATURES A FEW DEGREES.
AS FOR THOSE TEMPERATURES TODAY...LOCAL ANALYSIS HERE HAS SHOWN
THAT BIAS-CORRECTED GUIDANCE IS WORKING VERY WELL IN THESE VERY
MILD STRETCHES THIS WINTER...PARTICULARLY THE GEM AND THE EC. HAVE
BLENDED OUR GOING FORECAST HEAVILY TOWARDS THESE SOLUTIONS...AND
EVEN ADJUSTED UP FROM THERE IN SOME AREAS. WHILE THE CLOUDS WILL
EXPAND IN...CONTINUED LOW-LEVEL WARM ADVECTION WILL LIKELY
SUPPORT INCREASING SURFACE TEMPERATURES INTO THE
AFTERNOON...ALBEIT AT A SLOWER RATE. SO HAVE SOME QUICK MORNING
WARMING FORECAST FROM THE HIGH STARTING POINT VALUES...AND THEN
GRADUAL INCREASE THIS AFTERNOON. THIS APPROACH YIELDS REMARKABLY
MILD UPPER 50S TO LOWER 60 DEGREE READINGS BEING LIKELY IN SEVERAL
AREAS. EVEN MID 60S COULD BE TOUCHED IN THE EASTERN HALF OF THE
AREA IF THE RATE OF WARMING AFTER THE CLOUDS ARRIVE IS HIGHER THAN
INDICATED. PLEASE SEE THE CLIMATE SECTION BELOW FOR RECORD
INFORMATION.
AS FOR PRECIPITATION CHANCES THIS AFTERNOON INTO TONIGHT...THE
DEPTH OF THE CLOUDS INCREASE QUICKLY LATE THIS AFTERNOON INTO THE
EVENING. MARGINAL SATURATED ISENTROPIC ASCENT AND CONVERGENCE
AHEAD OF A COLD FRONT MOVING THROUGH...MAY OFFER SPORADIC LIGHT
RAIN OR DRIZZLE IN THE SOUTHEAST HALF OF THE FORECAST AREA DURING
THE LATE AFTERNOON AND EVENING. THE LIGHT RAIN MAY ACTUALLY BE
MORE SHOWERY...BUT LIMITED FORCING WILL PREVENT ANYTHING
APPRECIABLE.
WEDNESDAY AND THURSDAY...WHILE LOW-LEVEL TEMPERATURES ARE FORECAST
TO COOL DURING THIS PERIOD...THEY ARE STILL ON THE WARMER THAN
NORMAL SIDE. THE LACK OF SNOW COVER TOO SHOULD AID IN THE WARMER
BIAS-CORRECTED GUIDANCE BEING MORE ON TRACK. CLOUDS ALSO LOOK
LIMITED...ALTHOUGH CONFIDENCE IS CURRENTLY LOW ON WEDNESDAY
MORNING WITH A SOMEWHAT LIMITED SURGE BEHIND THIS FRONT MEANING
LINGERING STRATUS IS POSSIBLE. IF NOT THOUGH...TEMPERATURES
GETTING TO 50 ON WEDNESDAY SEEM PROBABLE...AND THEN WELL INTO THE
40S ON THURSDAY. RIDGING SHOULD ALLOW FOR ONLY CIRRUS BY THURSDAY.
LATE THIS WEEK INTO THE WEEKEND...THE PROGRESSIVE WESTERLY PATTERN
IS EXPECTED TO SLOW DOWN WITH A CUT OFF LOW AND A GENERAL BLOCKING
PATTERN DEVELOPING TO OUR WEST. DETAILS HAVE VARIED
SIGNIFICANTLY...BUT A CLEAR TREND IN THE GUIDANCE IS SLOWER WITH
PROGRESSING FORCING FOR PRECIPITATION EAST INTO OUR AREA. GIVEN
THAT PATTERN...THAT SEEMS REASONABLE AND HAVE ADJUSTED THE BLENDED
GUIDANCE FORECAST THAT WAY. THE SLOWER 31.00 EC WAS FOLLOWED
CLOSELY FOR DETAILS. SOME FORM OF INVERTED TROUGH OR WEAK SURFACE
LOW IS LIKELY TO DEVELOP AS THE CLOSED UPPER CIRCULATION WORKS
EAST...AND SUCH A FEATURE WOULD ALSO NOT FAVOR PRECIP FAR TO ITS
EAST. SO ONLY HAVE SMALL CHANCES DURING THE WEEKEND...WITH
FORECAST SOUNDINGS AND GENERAL THICKNESSES SLIGHTLY MORE
SUPPORTIVE OF RAIN THAN SNOW IF PRECIP OCCURS. IT IS STILL
FAVORED THAT NO PRECIPITATION WILL OCCUR THIS WEEKEND...ESPECIALLY
IF THE EC SOUTHERN TRACK OF THE CLOSED LOW WERE TO COME TO
FRUITION.
&&
.CLIMATE...
THE RECORD HIGH TODAY FOR CHICAGO IS 65 IN 1989. THE HIGH
TEMPERATURE IS MOST LIKELY TO BE 3 TO 7 DEGREES SHY OF THIS...BUT
IT COULD END UP GETTING VERY CLOSE. THE GOING FORECAST IS FOR THIS
TO BE THE WARMEST DAY THIS METEOROLOGICAL WINTER SO FAR. THIS WILL
BE THE TENTH DAY IN AT LEAST THE 50S SINCE DECEMBER 1ST /BASICALLY
ONE DAY A WEEK THIS WINTER SO FAR/. AS FOR ROCKFORD THE RECORD
HIGH IS 63 ALSO IN 1989. THE HIGH TEMPERATURE IS EXPECTED TO FALL
SEVERAL DEGREES SHORT...BUT CONFIDENCE IS LOWER AT ROCKFORD
DEPENDING ON HOW THE STRATUS EVOLVES IN /IT MAY REMAIN SOUTH OF
ROCKFORD/. THIS WILL BE THE NINTH DAY IN AT LEAST THE 50S THIS
METEOROLOGICAL WINTER AT ROCKFORD.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 20Z...
* MVFR CIGS THROUGH EARLY THIS EVENING.
* SWLY GUSTS TO 25KT DROPPING OFF LATE THIS AFTERNOON.
* SLIGHT CHANCE OF VIS DROPPING TO MVFR IN HZ/BR DURG EARLY
MORNING HOURS.
LENNING
//DISCUSSION...UPDATED 18Z...
GUSTY SWLY WINDS WILL CONTINUE INTO THE AFTERNOON AHEAD OF A WEAK
COLD FRONT MOVING INTO ERN IOWA. A PLUME OF LOW LEVEL MOISTURE
AHEAD OF THE FRONT HAS ALLOWED THE FORMATION OF A BKN STRATOCU
DECK EXTENDING FROM NRN MO TO NRN IL/IN. BASES OF THE CLOUD DECK
SHOULD STAY AT ARND 2.5KFT. AT ISSUANCE TIME...ORD/DPA/GYY WE JUST
TO THE NORTH OF THE BKN MVFR CIGS...AND ANTICIPATE THAT THE
COVERAGE SHOULD INCREASE TO BKN WITHIN THE HOUR OF ISSUANCE.
THE FRONT WILL STEADILY PUSH EWD THIS AFTERNOON...KEEPING WINDS
BRISK AND GUSTY UNTIL THE ASSOCIATED TROUGH CROSSES THE AREA LATE
THIS AFTERNOON AND EARLY THIS EVENING...RELAXING THE PRESSURE
GRADIENT OVER THE REGION. FOLLOWING THE FROPA...HIGH PRESSURE WILL
SPREAD ACROSS THE CENTRAL PLAINS AND INTO THE MIDWEST...ALLOWING
WINDS TO QUICKLY DROP OFF. DRIER AIR BEHIND THE FRONT SHOULD BRING
QUICKLY CLEARING SKIES. THE MAIN CONCERN FOR THE OVERNIGHT HOURS
WILL SHIFT TO VISIBILITY. SOME OF THE NUMERICAL GUIDANCE IS
INDICATING A CHANCE FOR VISBY REDUCTION TO MVFR AS SKIES CLEAR AND
WINDS DECREASE. THE ONE LIMITING FACTOR FOR VISIBILITY WILL BE LOW
LEVEL MOISTURE. THE AIRMASS BEHIND THE FRONT WILL BE RATHER DRY
AND IT IS UNCERTAIN THAT THERE WILL BE ENOUGH COOLING TO DROP THE
TEMPERATURE CLOSE ENOUGH TO THE DEWPOINT TO LEAD TO BR FORMATION.
SO...HAVE ONLY GONE WITH 6SM HZ FOR THE EARLY MORNING HOURS TO
BEGIN A TREND AND WILL MONITOR CONDITIONS CLOSELY TO SEE IF A
LOWER VISIBILITY FORECAST WILL BE WARRANTED FOR THE MORNING RUSH
HOURS. OTHERWISE...TOMORROW IS SHAPING UP TO BE A QUIET DAY WITH
NO OPERATIONALLY SIGNIFICANT WEATHER CONCERNS.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 20Z...
* MEDIUM CONFIDENCE ON CEILING TRENDS. UPSTREAM OBS MAY BE
SOMEWHAT MORE OPTIMISTIC THAN TRENDS IN LATEST TAFS. THIS WOULD
RESULT IN SHORTER PERIOD OF MVFR.
* MEDIUM CONFIDENCE IN GUST SPEEDS AND TIME THAT THEY WOULD BE
DIMINISHING THIS AFTERNOON.
LENNING
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
* WEDNESDAY NIGHT THROUGH FRIDAY...VFR
* SATURDAY AND SUNDAY...SLIGHT CHANCE OF RAIN OR SNOW
* MONDAY...VFR
SHEA
&&
.MARINE...
253 AM...LOW PRESSURE OVER THE UPPER MIDWEST WILL MOVE ACROSS
LAKE SUPERIOR THIS AFTERNOON AND INTO QUEBEC WEDNESDAY MORNING.
A WARM FRONT EXTENDING ACROSS NORTH CENTRAL LAKE MICHIGAN THIS
MORNING WILL LIFT NORTH AS THE LOW APPROACHES AND THE GRADIENT
WILL ALSO CONTINUE TO TIGHTEN...FROM SOUTH TO NORTH AS THE LOW
APPROACHES. SOUTHERLY WINDS CONTINUE TO GUST AS HIGH AS 30 KTS
ACROSS FAR SOUTHERN LAKE MICHIGAN EARLY THIS MORNING AND EXPECT
THESE HIGHER WINDS/GUSTS TO CONTINUE NORTH DURING THE DAY. COULD
BE SOME HIGHER GUSTS TO 35 KT GALES BUT RATHER LOW CONFIDENCE
REGARDING HOW PREVAILING THESE MAY BECOME AND WILL NEED TO BE
MONITORED THROUGH THE MORNING.
A TRAILING COLD FRONT FROM THIS LOW WILL MOVE ACROSS THE LAKE
EARLY THIS EVENING... SHIFTING WINDS WESTERLY WITH 30 KTS
POSSIBLE BEHIND THE FRONT... ESPECIALLY ACROSS THE NORTH HALF OR
SO OF THE LAKE. BROAD HIGH PRESSURE WILL BUILD ACROSS THE PLAINS
TONIGHT INTO WEDNESDAY AND THEN ACROSS THE SOUTHERN GREAT LAKES
REGION WEDNESDAY AFTERNOON INTO THURSDAY. NEW LOW PRESSURE IS
EXPECTED TO DEVELOP OVER THE SOUTHERN PLAINS THURSDAY NIGHT INTO
FRIDAY AND THEN MOVE NORTHEAST ACROSS THE SOUTHERN LAKES THIS
WEEKEND. WHILE WINDS WILL SHIFT TO THE NORTHEAST AS THIS LOW
APPROACHES...THERE STILL REMAINS QUITE A BIT OF UNCERTAINTY
REGARDING THE TRACK...STRENGTHEN AND TIMING OF THIS SYSTEM. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 10 PM TUESDAY.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1140 AM CST TUE JAN 31 2012
.DISCUSSION...
1054 AM CST
FOR MORNING UPDATE...
SOME MINOR TWEAKS TO GOING TEMP/SKY AND WX/POP GRIDS...THOUGH
FORECAST REMAINS LARGELY ON TRACK.
LOW PRESSURE POISED TO MOVE EAST ACROSS THE UPPER PENINSULA OF
MICHIGAN THIS AFTERNOON IN RESPONSE TO RATHER PRONOUNCED MID LEVEL
SHORT WAVE TROUGH PROPAGATING ACROSS THE UPPER MIDWEST. WARM SECTOR
SOUTH OF THE LOW ALREADY WARMING INTO THE LOW-MID 50S ACROSS THE CWA
AS OF 16Z. PERUSAL OF UPSTREAM SOUNDINGS AND LATEST MODEL LOW LEVEL
THERMAL PROGS CONTINUE TO SUGGEST MAX TEMPS ACROSS THE FORECAST AREA
POTENTIALLY RANGING FROM THE UPPER 50S NORTH TO THE MID 60S SOUTH...
HOWEVER GOES VISIBLE SATELLITE IMAGERY DOES DEPICT DEVELOPMENT OF
SOME STRATUS/STRATO CU ACROSS MO/IL IN REGION OF LOW LEVEL MOIST
ADVECTION AHEAD OF APPROACHING SHORT WAVE AND SURFACE TROUGH/COLD
FRONT. THIS CONTINUES TO MAKE FOR SOMEWHAT TRICKY AFTERNOON TEMP
FORECAST...WITH SOME VARIABLE COVERAGE IN OVERCAST CONDITIONS BUT AN
OVERALL INCREASE IN CLOUDINESS THROUGH THE AFTERNOON. HAVE TWEAKED
TEMPS UP JUST A LITTLE IN SOME SPOTS BASED ON TRENDS AND EXTRAPOLATED
NEAR TERM CLOUD TRENDS...BUT CANT ARGUE TOO MUCH WITH GOING
FORECAST.
IN ADDITION...POTENTIAL FOR DRIZZLE/SPRINKLES NOT LOOKING VERY
IMPRESSIVE AT THIS TIME...THOUGH GUIDANCE CONTINUES TO SUGGEST SOME
INCREASE IN POTENTIAL FOR SOME PATCHY LIGHT PRECIP ACROSS MAINLY THE
SOUTHEAST CWA VERY LATE THIS AFTERNOON/EVENING. HAVE ADJUSTED
LOCATION/COVERAGE ACCORDINGLY.
RATZER
//PREV DISCUSSION...
317 AM CST
THE ATTENTION ON THIS FORECAST WAS PRIMARILY DIRECTED TO
TEMPERATURES...WITH AN EMPHASIS ON TODAY AS NEAR RECORD TO RECORD
WARMTH IS ON PAR AGAIN FOR THE AREA. QUITE A DIFFERENCE FROM ONE
YEAR AGO TODAY...WHICH SAW THE AREA PREPARING FOR THE THIRD
LARGEST SNOWSTORM ON RECORD. AN ADDITIONAL CHALLENGE IN THE
FORECAST IS THAT BOTH WEDNESDAY AND THURSDAY ALSO ARE APPEARING
LIKELY TO BE WARMER THAN INITIALLY THOUGHT.
TEMPERATURES ARE STARTING NEARLY 30 DEGREES ABOVE NORMAL THIS
FINAL DAY OF JANUARY...WHICH IS FITTING FOR THIS MONTH THAT IS
AVERAGING 5 TO 6 DEGREES ABOVE NORMAL. SOUTHERLY WINDS AND
INCREASING LOW-LEVEL MOISTURE THROUGHOUT LAST NIGHT INTO THIS
MORNING HAVE AIDED THESE MILD READINGS. THE ANTICIPATED
STRATUS/STRATOCU IS DEVELOPING QUICKLY NORTHEAST FROM THE SOUTHERN
PLAINS/OZARKS EARLY THIS MORNING...LINING UP WELL WITH MODEL
DIAGNOSTIC SOLUTIONS OF MOISTURE TRANSPORT AND CONVERGENCE IN THE
LOW LEVELS /ROUGHLY 850-925MB/.
EVEN AHEAD OF THESE LOW CLOUDS...MODEL GUIDANCE CONTINUES TO SHOW
BOTH A TOO MOIST AND COOL BIAS IN THE LOW-LEVELS...SOME LIKELY DUE
TO FALSE SNOW COVER AND/OR TOO COLD OF GROUND COVER. JUST THE
31.00 GFS AND NAMELY THE NAM SOUNDINGS ACROSS THE AREA REVEALED
THIS BIAS ALMOST IMMEDIATELY AFTER THEIR INITIALIZATION HOURS. SO
HAVE GUIDED MORE ON ABSOLUTE MOISTURE VALUES AND SATURATION NEAR
THE TOP OF THE ADAPTED MIXED-LAYER LATER THIS MORNING /~4000 FT/
FOR CLOUD INDICATIONS. THE MOISTURE CONVERGENCE FORECAST FROM THE
RUC AND NAM LINE UP WELL FROM SOUTHEAST IA INTO NORTHERN IL AND
EXPECT THE CLOUDS TO EXPAND INTO THAT AREA DURING THE LATE
MORNING. RUC PARCEL TRAJECTORIES WOULD INDICATE NEAR A 12 PM
ARRIVAL IN CHICAGO BASED ON CURRENT PLACEMENT OF THE LOW
CLOUDS...BUT SOME LEAD SATURATION MAY CAUSE IT TO BE A LITTLE
QUICKER. THE STRATUS PLUME AND HOW QUICKLY IT MOVES IN WILL LIKELY
IMPACT TEMPERATURES A FEW DEGREES.
AS FOR THOSE TEMPERATURES TODAY...LOCAL ANALYSIS HERE HAS SHOWN
THAT BIAS-CORRECTED GUIDANCE IS WORKING VERY WELL IN THESE VERY
MILD STRETCHES THIS WINTER...PARTICULARLY THE GEM AND THE EC. HAVE
BLENDED OUR GOING FORECAST HEAVILY TOWARDS THESE SOLUTIONS...AND
EVEN ADJUSTED UP FROM THERE IN SOME AREAS. WHILE THE CLOUDS WILL
EXPAND IN...CONTINUED LOW-LEVEL WARM ADVECTION WILL LIKELY
SUPPORT INCREASING SURFACE TEMPERATURES INTO THE
AFTERNOON...ALBEIT AT A SLOWER RATE. SO HAVE SOME QUICK MORNING
WARMING FORECAST FROM THE HIGH STARTING POINT VALUES...AND THEN
GRADUAL INCREASE THIS AFTERNOON. THIS APPROACH YIELDS REMARKABLY
MILD UPPER 50S TO LOWER 60 DEGREE READINGS BEING LIKELY IN SEVERAL
AREAS. EVEN MID 60S COULD BE TOUCHED IN THE EASTERN HALF OF THE
AREA IF THE RATE OF WARMING AFTER THE CLOUDS ARRIVE IS HIGHER THAN
INDICATED. PLEASE SEE THE CLIMATE SECTION BELOW FOR RECORD
INFORMATION.
AS FOR PRECIPITATION CHANCES THIS AFTERNOON INTO TONIGHT...THE
DEPTH OF THE CLOUDS INCREASE QUICKLY LATE THIS AFTERNOON INTO THE
EVENING. MARGINAL SATURATED ISENTROPIC ASCENT AND CONVERGENCE
AHEAD OF A COLD FRONT MOVING THROUGH...MAY OFFER SPORADIC LIGHT
RAIN OR DRIZZLE IN THE SOUTHEAST HALF OF THE FORECAST AREA DURING
THE LATE AFTERNOON AND EVENING. THE LIGHT RAIN MAY ACTUALLY BE
MORE SHOWERY...BUT LIMITED FORCING WILL PREVENT ANYTHING
APPRECIABLE.
WEDNESDAY AND THURSDAY...WHILE LOW-LEVEL TEMPERATURES ARE FORECAST
TO COOL DURING THIS PERIOD...THEY ARE STILL ON THE WARMER THAN
NORMAL SIDE. THE LACK OF SNOW COVER TOO SHOULD AID IN THE WARMER
BIAS-CORRECTED GUIDANCE BEING MORE ON TRACK. CLOUDS ALSO LOOK
LIMITED...ALTHOUGH CONFIDENCE IS CURRENTLY LOW ON WEDNESDAY
MORNING WITH A SOMEWHAT LIMITED SURGE BEHIND THIS FRONT MEANING
LINGERING STRATUS IS POSSIBLE. IF NOT THOUGH...TEMPERATURES
GETTING TO 50 ON WEDNESDAY SEEM PROBABLE...AND THEN WELL INTO THE
40S ON THURSDAY. RIDGING SHOULD ALLOW FOR ONLY CIRRUS BY THURSDAY.
LATE THIS WEEK INTO THE WEEKEND...THE PROGRESSIVE WESTERLY PATTERN
IS EXPECTED TO SLOW DOWN WITH A CUT OFF LOW AND A GENERAL BLOCKING
PATTERN DEVELOPING TO OUR WEST. DETAILS HAVE VARIED
SIGNIFICANTLY...BUT A CLEAR TREND IN THE GUIDANCE IS SLOWER WITH
PROGRESSING FORCING FOR PRECIPITATION EAST INTO OUR AREA. GIVEN
THAT PATTERN...THAT SEEMS REASONABLE AND HAVE ADJUSTED THE BLENDED
GUIDANCE FORECAST THAT WAY. THE SLOWER 31.00 EC WAS FOLLOWED
CLOSELY FOR DETAILS. SOME FORM OF INVERTED TROUGH OR WEAK SURFACE
LOW IS LIKELY TO DEVELOP AS THE CLOSED UPPER CIRCULATION WORKS
EAST...AND SUCH A FEATURE WOULD ALSO NOT FAVOR PRECIP FAR TO ITS
EAST. SO ONLY HAVE SMALL CHANCES DURING THE WEEKEND...WITH
FORECAST SOUNDINGS AND GENERAL THICKNESSES SLIGHTLY MORE
SUPPORTIVE OF RAIN THAN SNOW IF PRECIP OCCURS. IT IS STILL
FAVORED THAT NO PRECIPITATION WILL OCCUR THIS WEEKEND...ESPECIALLY
IF THE EC SOUTHERN TRACK OF THE CLOSED LOW WERE TO COME TO
FRUITION.
&&
.CLIMATE...
THE RECORD HIGH TODAY FOR CHICAGO IS 65 IN 1989. THE HIGH
TEMPERATURE IS MOST LIKELY TO BE 3 TO 7 DEGREES SHY OF THIS...BUT
IT COULD END UP GETTING VERY CLOSE. THE GOING FORECAST IS FOR THIS
TO BE THE WARMEST DAY THIS METEOROLOGICAL WINTER SO FAR. THIS WILL
BE THE TENTH DAY IN AT LEAST THE 50S SINCE DECEMBER 1ST /BASICALLY
ONE DAY A WEEK THIS WINTER SO FAR/. AS FOR ROCKFORD THE RECORD
HIGH IS 63 ALSO IN 1989. THE HIGH TEMPERATURE IS EXPECTED TO FALL
SEVERAL DEGREES SHORT...BUT CONFIDENCE IS LOWER AT ROCKFORD
DEPENDING ON HOW THE STRATUS EVOLVES IN /IT MAY REMAIN SOUTH OF
ROCKFORD/. THIS WILL BE THE NINTH DAY IN AT LEAST THE 50S THIS
METEOROLOGICAL WINTER AT ROCKFORD.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 18Z...
* CHANCE OF MVFR CIGS THROUGH EARLY THIS EVENING.
* SWLY WINDS GUSTING TO 25KT THROUGH MID-AFTERNOON.
* SLIGHT CHANCE OF VIS DROPPING TO MVFR IN HZ/BR DURG EARLY
MORNING HOURS.
KREIN
//DISCUSSION...UPDATED 18Z...
GUSTY SWLY WINDS WILL CONTINUE INTO THE AFTERNOON AHEAD OF A WEAK
COLD FRONT MOVING INTO ERN IOWA. A PLUME OF LOW LEVEL MOISTURE
AHEAD OF THE FRONT HAS ALLOWED THE FORMATION OF A BKN STRATOCU
DECK EXTENDING FROM NRN MO TO NRN IL/IN. BASES OF THE CLOUD DECK
SHOULD STAY AT ARND 2.5KFT. AT ISSUANCE TIME...ORD/DPA/GYY WE JUST
TO THE NORTH OF THE BKN MVFR CIGS...AND ANTICIPATE THAT THE
COVERAGE SHOULD INCREASE TO BKN WITHIN THE HOUR OF ISSUANCE.
THE FRONT WILL STEADILY PUSH EWD THIS AFTERNOON...KEEPING WINDS
BRISK AND GUSTY UNTIL THE ASSOCIATED TROUGH CROSSES THE AREA LATE
THIS AFTERNOON AND EARLY THIS EVENING...RELAXING THE PRESSURE
GRADIENT OVER THE REGION. FOLLOWING THE FROPA...HIGH PRESSURE WILL
SPREAD ACROSS THE CENTRAL PLAINS AND INTO THE MIDWEST...ALLOWING
WINDS TO QUICKLY DROP OFF. DRIER AIR BEHIND THE FRONT SHOULD BRING
QUICKLY CLEARING SKIES. THE MAIN CONCERN FOR THE OVERNIGHT HOURS
WILL SHIFT TO VISIBILITY. SOME OF THE NUMERICAL GUIDANCE IS
INDICATING A CHANCE FOR VISBY REDUCTION TO MVFR AS SKIES CLEAR AND
WINDS DECREASE. THE ONE LIMITING FACTOR FOR VISIBILITY WILL BE LOW
LEVEL MOISTURE. THE AIRMASS BEHIND THE FRONT WILL BE RATHER DRY
AND IT IS UNCERTAIN THAT THERE WILL BE ENOUGH COOLING TO DROP THE
TEMPERATURE CLOSE ENOUGH TO THE DEWPOINT TO LEAD TO BR FORMATION.
SO...HAVE ONLY GONE WITH 6SM HZ FOR THE EARLY MORNING HOURS TO
BEGIN A TREND AND WILL MONITOR CONDITIONS CLOSELY TO SEE IF A
LOWER VISIBILITY FORECAST WILL BE WARRANTED FOR THE MORNING RUSH
HOURS. OTHERWISE...TOMORROW IS SHAPING UP TO BE A QUIET DAY WITH
NO OPERATIONALLY SIGNIFICANT WEATHER CONCERNS.
KREIN
//ORD AND MDW CONFIDENCE...UPDATED 18Z...
* MODERATE CONFIDENCE IN CEILING AND VISIBILITY TRENDS.
* MODERATE TO HIGH CONFIDENCE IN WIND TRENDS.
* HIGH CONFIDENCE IN ALL FORECAST ELEMENTS.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
* WEDNESDAY NIGHT THROUGH FRIDAY...VFR
* SATURDAY AND SUNDAY...SLIGHT CHANCE OF RAIN OR SNOW
* MONDAY...VFR
SHEA
&&
.MARINE...
253 AM...LOW PRESSURE OVER THE UPPER MIDWEST WILL MOVE ACROSS
LAKE SUPERIOR THIS AFTERNOON AND INTO QUEBEC WEDNESDAY MORNING.
A WARM FRONT EXTENDING ACROSS NORTH CENTRAL LAKE MICHIGAN THIS
MORNING WILL LIFT NORTH AS THE LOW APPROACHES AND THE GRADIENT
WILL ALSO CONTINUE TO TIGHTEN...FROM SOUTH TO NORTH AS THE LOW
APPROACHES. SOUTHERLY WINDS CONTINUE TO GUST AS HIGH AS 30 KTS
ACROSS FAR SOUTHERN LAKE MICHIGAN EARLY THIS MORNING AND EXPECT
THESE HIGHER WINDS/GUSTS TO CONTINUE NORTH DURING THE DAY. COULD
BE SOME HIGHER GUSTS TO 35 KT GALES BUT RATHER LOW CONFIDENCE
REGARDING HOW PREVAILING THESE MAY BECOME AND WILL NEED TO BE
MONITORED THROUGH THE MORNING.
A TRAILING COLD FRONT FROM THIS LOW WILL MOVE ACROSS THE LAKE
EARLY THIS EVENING... SHIFTING WINDS WESTERLY WITH 30 KTS
POSSIBLE BEHIND THE FRONT... ESPECIALLY ACROSS THE NORTH HALF OR
SO OF THE LAKE. BROAD HIGH PRESSURE WILL BUILD ACROSS THE PLAINS
TONIGHT INTO WEDNESDAY AND THEN ACROSS THE SOUTHERN GREAT LAKES
REGION WEDNESDAY AFTERNOON INTO THURSDAY. NEW LOW PRESSURE IS
EXPECTED TO DEVELOP OVER THE SOUTHERN PLAINS THURSDAY NIGHT INTO
FRIDAY AND THEN MOVE NORTHEAST ACROSS THE SOUTHERN LAKES THIS
WEEKEND. WHILE WINDS WILL SHIFT TO THE NORTHEAST AS THIS LOW
APPROACHES...THERE STILL REMAINS QUITE A BIT OF UNCERTAINTY
REGARDING THE TRACK...STRENGTHEN AND TIMING OF THIS SYSTEM. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 10 PM TUESDAY.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1055 AM CST TUE JAN 31 2012
.DISCUSSION...
1054 AM CST
FOR MORNING UPDATE...
SOME MINOR TWEAKS TO GOING TEMP/SKY AND WX/POP GRIDS...THOUGH
FORECAST REMAINS LARGELY ON TRACK.
LOW PRESSURE POISED TO MOVE EAST ACROSS THE UPPER PENINSULA OF
MICHIGAN THIS AFTERNOON IN RESPONSE TO RATHER PRONOUNCED MID LEVEL
SHORT WAVE TROUGH PROPAGATING ACROSS THE UPPER MIDWEST. WARM SECTOR
SOUTH OF THE LOW ALREADY WARMING INTO THE LOW-MID 50S ACROSS THE CWA
AS OF 16Z. PERUSAL OF UPSTREAM SOUNDINGS AND LATEST MODEL LOW LEVEL
THERMAL PROGS CONTINUE TO SUGGEST MAX TEMPS ACROSS THE FORECAST AREA
POTENTIALLY RANGING FROM THE UPPER 50S NORTH TO THE MID 60S SOUTH...
HOWEVER GOES VISIBLE SATELLITE IMAGERY DOES DEPICT DEVELOPMENT OF
SOME STRATUS/STRATO CU ACROSS MO/IL IN REGION OF LOW LEVEL MOIST
ADVECTION AHEAD OF APPROACHING SHORT WAVE AND SURFACE TROUGH/COLD
FRONT. THIS CONTINUES TO MAKE FOR SOMEWHAT TRICKY AFTERNOON TEMP
FORECAST...WITH SOME VARIABLE COVERAGE IN OVERCAST CONDITIONS BUT AN
OVERALL INCREASE IN CLOUDINESS THROUGH THE AFTERNOON. HAVE TWEAKED
TEMPS UP JUST A LITTLE IN SOME SPOTS BASED ON TRENDS AND EXTRAPOLATED
NEAR TERM CLOUD TRENDS...BUT CANT ARGUE TOO MUCH WITH GOING
FORECAST.
IN ADDITION...POTENTIAL FOR DRIZZLE/SPRINKLES NOT LOOKING VERY
IMPRESSIVE AT THIS TIME...THOUGH GUIDANCE CONTINUES TO SUGGEST SOME
INCREASE IN POTENTIAL FOR SOME PATCHY LIGHT PRECIP ACROSS MAINLY THE
SOUTHEAST CWA VERY LATE THIS AFTERNOON/EVENING. HAVE ADJUSTED
LOCATION/COVERAGE ACCORDINGLY.
RATZER
&&
.PREV DISCUSSION...
317 AM CST
THE ATTENTION ON THIS FORECAST WAS PRIMARILY DIRECTED TO
TEMPERATURES...WITH AN EMPHASIS ON TODAY AS NEAR RECORD TO RECORD
WARMTH IS ON PAR AGAIN FOR THE AREA. QUITE A DIFFERENCE FROM ONE
YEAR AGO TODAY...WHICH SAW THE AREA PREPARING FOR THE THIRD
LARGEST SNOWSTORM ON RECORD. AN ADDITIONAL CHALLENGE IN THE
FORECAST IS THAT BOTH WEDNESDAY AND THURSDAY ALSO ARE APPEARING
LIKELY TO BE WARMER THAN INITIALLY THOUGHT.
TEMPERATURES ARE STARTING NEARLY 30 DEGREES ABOVE NORMAL THIS
FINAL DAY OF JANUARY...WHICH IS FITTING FOR THIS MONTH THAT IS
AVERAGING 5 TO 6 DEGREES ABOVE NORMAL. SOUTHERLY WINDS AND
INCREASING LOW-LEVEL MOISTURE THROUGHOUT LAST NIGHT INTO THIS
MORNING HAVE AIDED THESE MILD READINGS. THE ANTICIPATED
STRATUS/STRATOCU IS DEVELOPING QUICKLY NORTHEAST FROM THE SOUTHERN
PLAINS/OZARKS EARLY THIS MORNING...LINING UP WELL WITH MODEL
DIAGNOSTIC SOLUTIONS OF MOISTURE TRANSPORT AND CONVERGENCE IN THE
LOW LEVELS /ROUGHLY 850-925MB/.
EVEN AHEAD OF THESE LOW CLOUDS...MODEL GUIDANCE CONTINUES TO SHOW
BOTH A TOO MOIST AND COOL BIAS IN THE LOW-LEVELS...SOME LIKELY DUE
TO FALSE SNOW COVER AND/OR TOO COLD OF GROUND COVER. JUST THE
31.00 GFS AND NAMELY THE NAM SOUNDINGS ACROSS THE AREA REVEALED
THIS BIAS ALMOST IMMEDIATELY AFTER THEIR INITIALIZATION HOURS. SO
HAVE GUIDED MORE ON ABSOLUTE MOISTURE VALUES AND SATURATION NEAR
THE TOP OF THE ADAPTED MIXED-LAYER LATER THIS MORNING /~4000 FT/
FOR CLOUD INDICATIONS. THE MOISTURE CONVERGENCE FORECAST FROM THE
RUC AND NAM LINE UP WELL FROM SOUTHEAST IA INTO NORTHERN IL AND
EXPECT THE CLOUDS TO EXPAND INTO THAT AREA DURING THE LATE
MORNING. RUC PARCEL TRAJECTORIES WOULD INDICATE NEAR A 12 PM
ARRIVAL IN CHICAGO BASED ON CURRENT PLACEMENT OF THE LOW
CLOUDS...BUT SOME LEAD SATURATION MAY CAUSE IT TO BE A LITTLE
QUICKER. THE STRATUS PLUME AND HOW QUICKLY IT MOVES IN WILL LIKELY
IMPACT TEMPERATURES A FEW DEGREES.
AS FOR THOSE TEMPERATURES TODAY...LOCAL ANALYSIS HERE HAS SHOWN
THAT BIAS-CORRECTED GUIDANCE IS WORKING VERY WELL IN THESE VERY
MILD STRETCHES THIS WINTER...PARTICULARLY THE GEM AND THE EC. HAVE
BLENDED OUR GOING FORECAST HEAVILY TOWARDS THESE SOLUTIONS...AND
EVEN ADJUSTED UP FROM THERE IN SOME AREAS. WHILE THE CLOUDS WILL
EXPAND IN...CONTINUED LOW-LEVEL WARM ADVECTION WILL LIKELY
SUPPORT INCREASING SURFACE TEMPERATURES INTO THE
AFTERNOON...ALBEIT AT A SLOWER RATE. SO HAVE SOME QUICK MORNING
WARMING FORECAST FROM THE HIGH STARTING POINT VALUES...AND THEN
GRADUAL INCREASE THIS AFTERNOON. THIS APPROACH YIELDS REMARKABLY
MILD UPPER 50S TO LOWER 60 DEGREE READINGS BEING LIKELY IN SEVERAL
AREAS. EVEN MID 60S COULD BE TOUCHED IN THE EASTERN HALF OF THE
AREA IF THE RATE OF WARMING AFTER THE CLOUDS ARRIVE IS HIGHER THAN
INDICATED. PLEASE SEE THE CLIMATE SECTION BELOW FOR RECORD
INFORMATION.
AS FOR PRECIPITATION CHANCES THIS AFTERNOON INTO TONIGHT...THE
DEPTH OF THE CLOUDS INCREASE QUICKLY LATE THIS AFTERNOON INTO THE
EVENING. MARGINAL SATURATED ISENTROPIC ASCENT AND CONVERGENCE
AHEAD OF A COLD FRONT MOVING THROUGH...MAY OFFER SPORADIC LIGHT
RAIN OR DRIZZLE IN THE SOUTHEAST HALF OF THE FORECAST AREA DURING
THE LATE AFTERNOON AND EVENING. THE LIGHT RAIN MAY ACTUALLY BE
MORE SHOWERY...BUT LIMITED FORCING WILL PREVENT ANYTHING
APPRECIABLE.
WEDNESDAY AND THURSDAY...WHILE LOW-LEVEL TEMPERATURES ARE FORECAST
TO COOL DURING THIS PERIOD...THEY ARE STILL ON THE WARMER THAN
NORMAL SIDE. THE LACK OF SNOW COVER TOO SHOULD AID IN THE WARMER
BIAS-CORRECTED GUIDANCE BEING MORE ON TRACK. CLOUDS ALSO LOOK
LIMITED...ALTHOUGH CONFIDENCE IS CURRENTLY LOW ON WEDNESDAY
MORNING WITH A SOMEWHAT LIMITED SURGE BEHIND THIS FRONT MEANING
LINGERING STRATUS IS POSSIBLE. IF NOT THOUGH...TEMPERATURES
GETTING TO 50 ON WEDNESDAY SEEM PROBABLE...AND THEN WELL INTO THE
40S ON THURSDAY. RIDGING SHOULD ALLOW FOR ONLY CIRRUS BY THURSDAY.
LATE THIS WEEK INTO THE WEEKEND...THE PROGRESSIVE WESTERLY PATTERN
IS EXPECTED TO SLOW DOWN WITH A CUT OFF LOW AND A GENERAL BLOCKING
PATTERN DEVELOPING TO OUR WEST. DETAILS HAVE VARIED
SIGNIFICANTLY...BUT A CLEAR TREND IN THE GUIDANCE IS SLOWER WITH
PROGRESSING FORCING FOR PRECIPITATION EAST INTO OUR AREA. GIVEN
THAT PATTERN...THAT SEEMS REASONABLE AND HAVE ADJUSTED THE BLENDED
GUIDANCE FORECAST THAT WAY. THE SLOWER 31.00 EC WAS FOLLOWED
CLOSELY FOR DETAILS. SOME FORM OF INVERTED TROUGH OR WEAK SURFACE
LOW IS LIKELY TO DEVELOP AS THE CLOSED UPPER CIRCULATION WORKS
EAST...AND SUCH A FEATURE WOULD ALSO NOT FAVOR PRECIP FAR TO ITS
EAST. SO ONLY HAVE SMALL CHANCES DURING THE WEEKEND...WITH
FORECAST SOUNDINGS AND GENERAL THICKNESSES SLIGHTLY MORE
SUPPORTIVE OF RAIN THAN SNOW IF PRECIP OCCURS. IT IS STILL
FAVORED THAT NO PRECIPITATION WILL OCCUR THIS WEEKEND...ESPECIALLY
IF THE EC SOUTHERN TRACK OF THE CLOSED LOW WERE TO COME TO
FRUITION.
&&
.CLIMATE...
THE RECORD HIGH TODAY FOR CHICAGO IS 65 IN 1989. THE HIGH
TEMPERATURE IS MOST LIKELY TO BE 3 TO 7 DEGREES SHY OF THIS...BUT
IT COULD END UP GETTING VERY CLOSE. THE GOING FORECAST IS FOR THIS
TO BE THE WARMEST DAY THIS METEOROLOGICAL WINTER SO FAR. THIS WILL
BE THE TENTH DAY IN AT LEAST THE 50S SINCE DECEMBER 1ST /BASICALLY
ONE DAY A WEEK THIS WINTER SO FAR/. AS FOR ROCKFORD THE RECORD
HIGH IS 63 ALSO IN 1989. THE HIGH TEMPERATURE IS EXPECTED TO FALL
SEVERAL DEGREES SHORT...BUT CONFIDENCE IS LOWER AT ROCKFORD
DEPENDING ON HOW THE STRATUS EVOLVES IN /IT MAY REMAIN SOUTH OF
ROCKFORD/. THIS WILL BE THE NINTH DAY IN AT LEAST THE 50S THIS
METEOROLOGICAL WINTER AT ROCKFORD.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* SSWLY WINDS GUSTING TO 25KT VEERING SWLY THIS AFTERNOON.
* ANTICIPATED MVFR CIGS THIS AFTERNOON LOOKING LESS LIKELY.
KREIN
//DISCUSSION...UPDATED 12Z...
MORNING FORECAST HAS A FEW CHALLENGES. THE FIRST WILL BE WITH LLWS
LIKELIHOOD THROUGH THE EARLY MORNING HOURS. ORD/MDW 1 MINUTE ASOS
DATA HAS BEEN HAVING ON AND OFF GUSTS IN THE 17-20KT RANGE
OVERNIGHT...WITH SUSTAINED 10-15KT WINDS. 12Z SOUNDINGS FROM ILX
AND DVN MAINTAINED A GENERAL 55KT WIND OUT OF ROUGHLY 240 AT 1.9
KFT. EXPECT THE THREAT TO CONTINUE INTO THROUGH ROUGHLY 15Z OR SO
WHEN HIGHER SURFACE GUSTS BEGIN AND AS THE HIGHEST LOWER LEVEL
WINDS SHIFT EAST. A FRONT WILL MOVE ACROSS THE AIRSPACE LATE THIS
EVENING SHIFTING WINDS FROM WEST TO NORTHWEST.
THE SECOND CHALLENGE WILL BE WITH CLOUD COVER. CONTINUED RUN AFTER
RUN OF ALL FORECAST GUIDANCE HAS BEEN OVERDOING THE LOWEST LEVEL
RH FIELDS...AND BRINGING IN HIGH IFR TO LOW MVFR STRATUS ACROSS
THE EASTERN TERMINALS INTO THE LATE MORNING HOURS. STILL BELIEVE
THAT WE WILL SEE A HIGHER END MVFR TO LOWER END VFR CIG SWING
ACROSS THE REGION BEYOND THE 19Z HOUR TODAY. A MANUAL TIME OF
ARRIVAL OF THE PRESENT FIELD ACROSS NORTHWEST MISSOURI WOULD BRING
THE DECK INTO ORD BY 17Z...AND MET/MAV WOULD LEAD YOU TO BELIEVE
THAT THE TERMINALS WOULD SEE CIGS BELOW 015. DISCOUNTING THAT FOR
A FEW REASONS. FIRST IS DUE TO HIGHER RH BIAS THAT HAS BEEN
ONGOING...AND ALSO FEEL WITH DAYTIME MIXING...CIGS SHOULD BEGIN TO
RAISE. ALSO...H92-95 FLOW WILL TURN A LITTLE MORE WESTERLY THIS
MORNING...AND THE MAIN MOISTURE AXIS SHOULD TURN A LITTLE MORE
EASTERLY. WITH THE BULK OF THE MOISTURE STAYING TO THE SOUTH OF
ORD/MDW...FEEL THAT THE TERMINALS SHOULD NOT SEE ANY -DZ OUTSIDE
OF GYY...WHERE A LATE EVENING TIMING LOOKS BEST AT THIS
POINT...BUT CONFIDENCE REMAINS LOW ENOUGH THAT WILL ONLY CARRY A
PROB30 FOR LIGHT RAIN AT THIS POINT.
SHEA
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MODERATE CONFIDENCE THAT CIGS WILL REMAIN VFR THROUGH EARLY
THIS EVENING UNTIL FROPA...LOWER CONFIDENCE IN CHANCES FOR MVFR
CIGS FOR A SHORT TIME AFTER FROPA.
* LOW CONFIDENCE IN -DZ POTENTIAL IN THE LATE AFTERNOON.
* MODERATE-HIGH CONFIDENCE ALL OTHER FORECAST ELEMENTS.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
* WEDNESDAY NIGHT THROUGH FRIDAY...VFR
* SATURDAY AND SUNDAY...SLIGHT CHANCE OF RAIN OR SNOW
* MONDAY...VFR
SHEA
&&
.MARINE...
253 AM...LOW PRESSURE OVER THE UPPER MIDWEST WILL MOVE ACROSS
LAKE SUPERIOR THIS AFTERNOON AND INTO QUEBEC WEDNESDAY MORNING.
A WARM FRONT EXTENDING ACROSS NORTH CENTRAL LAKE MICHIGAN THIS
MORNING WILL LIFT NORTH AS THE LOW APPROACHES AND THE GRADIENT
WILL ALSO CONTINUE TO TIGHTEN...FROM SOUTH TO NORTH AS THE LOW
APPROACHES. SOUTHERLY WINDS CONTINUE TO GUST AS HIGH AS 30 KTS
ACROSS FAR SOUTHERN LAKE MICHIGAN EARLY THIS MORNING AND EXPECT
THESE HIGHER WINDS/GUSTS TO CONTINUE NORTH DURING THE DAY. COULD
BE SOME HIGHER GUSTS TO 35 KT GALES BUT RATHER LOW CONFIDENCE
REGARDING HOW PREVAILING THESE MAY BECOME AND WILL NEED TO BE
MONITORED THROUGH THE MORNING.
A TRAILING COLD FRONT FROM THIS LOW WILL MOVE ACROSS THE LAKE
EARLY THIS EVENING... SHIFTING WINDS WESTERLY WITH 30 KTS
POSSIBLE BEHIND THE FRONT... ESPECIALLY ACROSS THE NORTH HALF OR
SO OF THE LAKE. BROAD HIGH PRESSURE WILL BUILD ACROSS THE PLAINS
TONIGHT INTO WEDNESDAY AND THEN ACROSS THE SOUTHERN GREAT LAKES
REGION WEDNESDAY AFTERNOON INTO THURSDAY. NEW LOW PRESSURE IS
EXPECTED TO DEVELOP OVER THE SOUTHERN PLAINS THURSDAY NIGHT INTO
FRIDAY AND THEN MOVE NORTHEAST ACROSS THE SOUTHERN LAKES THIS
WEEKEND. WHILE WINDS WILL SHIFT TO THE NORTHEAST AS THIS LOW
APPROACHES...THERE STILL REMAINS QUITE A BIT OF UNCERTAINTY
REGARDING THE TRACK...STRENGTHEN AND TIMING OF THIS SYSTEM. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 10 PM TUESDAY.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
959 AM CST TUE JAN 31 2012
.DISCUSSION...
317 AM CST
THE ATTENTION ON THIS FORECAST WAS PRIMARILY DIRECTED TO
TEMPERATURES...WITH AN EMPHASIS ON TODAY AS NEAR RECORD TO RECORD
WARMTH IS ON PAR AGAIN FOR THE AREA. QUITE A DIFFERENCE FROM ONE
YEAR AGO TODAY...WHICH SAW THE AREA PREPARING FOR THE THIRD
LARGEST SNOWSTORM ON RECORD. AN ADDITIONAL CHALLENGE IN THE
FORECAST IS THAT BOTH WEDNESDAY AND THURSDAY ALSO ARE APPEARING
LIKELY TO BE WARMER THAN INITIALLY THOUGHT.
TEMPERATURES ARE STARTING NEARLY 30 DEGREES ABOVE NORMAL THIS
FINAL DAY OF JANUARY...WHICH IS FITTING FOR THIS MONTH THAT IS
AVERAGING 5 TO 6 DEGREES ABOVE NORMAL. SOUTHERLY WINDS AND
INCREASING LOW-LEVEL MOISTURE THROUGHOUT LAST NIGHT INTO THIS
MORNING HAVE AIDED THESE MILD READINGS. THE ANTICIPATED
STRATUS/STRATOCU IS DEVELOPING QUICKLY NORTHEAST FROM THE SOUTHERN
PLAINS/OZARKS EARLY THIS MORNING...LINING UP WELL WITH MODEL
DIAGNOSTIC SOLUTIONS OF MOISTURE TRANSPORT AND CONVERGENCE IN THE
LOW LEVELS /ROUGHLY 850-925MB/.
EVEN AHEAD OF THESE LOW CLOUDS...MODEL GUIDANCE CONTINUES TO SHOW
BOTH A TOO MOIST AND COOL BIAS IN THE LOW-LEVELS...SOME LIKELY DUE
TO FALSE SNOW COVER AND/OR TOO COLD OF GROUND COVER. JUST THE
31.00 GFS AND NAMELY THE NAM SOUNDINGS ACROSS THE AREA REVEALED
THIS BIAS ALMOST IMMEDIATELY AFTER THEIR INITIALIZATION HOURS. SO
HAVE GUIDED MORE ON ABSOLUTE MOISTURE VALUES AND SATURATION NEAR
THE TOP OF THE ADAPTED MIXED-LAYER LATER THIS MORNING /~4000 FT/
FOR CLOUD INDICATIONS. THE MOISTURE CONVERGENCE FORECAST FROM THE
RUC AND NAM LINE UP WELL FROM SOUTHEAST IA INTO NORTHERN IL AND
EXPECT THE CLOUDS TO EXPAND INTO THAT AREA DURING THE LATE
MORNING. RUC PARCEL TRAJECTORIES WOULD INDICATE NEAR A 12 PM
ARRIVAL IN CHICAGO BASED ON CURRENT PLACEMENT OF THE LOW
CLOUDS...BUT SOME LEAD SATURATION MAY CAUSE IT TO BE A LITTLE
QUICKER. THE STRATUS PLUME AND HOW QUICKLY IT MOVES IN WILL LIKELY
IMPACT TEMPERATURES A FEW DEGREES.
AS FOR THOSE TEMPERATURES TODAY...LOCAL ANALYSIS HERE HAS SHOWN
THAT BIAS-CORRECTED GUIDANCE IS WORKING VERY WELL IN THESE VERY
MILD STRETCHES THIS WINTER...PARTICULARLY THE GEM AND THE EC. HAVE
BLENDED OUR GOING FORECAST HEAVILY TOWARDS THESE SOLUTIONS...AND
EVEN ADJUSTED UP FROM THERE IN SOME AREAS. WHILE THE CLOUDS WILL
EXPAND IN...CONTINUED LOW-LEVEL WARM ADVECTION WILL LIKELY
SUPPORT INCREASING SURFACE TEMPERATURES INTO THE
AFTERNOON...ALBEIT AT A SLOWER RATE. SO HAVE SOME QUICK MORNING
WARMING FORECAST FROM THE HIGH STARTING POINT VALUES...AND THEN
GRADUAL INCREASE THIS AFTERNOON. THIS APPROACH YIELDS REMARKABLY
MILD UPPER 50S TO LOWER 60 DEGREE READINGS BEING LIKELY IN SEVERAL
AREAS. EVEN MID 60S COULD BE TOUCHED IN THE EASTERN HALF OF THE
AREA IF THE RATE OF WARMING AFTER THE CLOUDS ARRIVE IS HIGHER THAN
INDICATED. PLEASE SEE THE CLIMATE SECTION BELOW FOR RECORD
INFORMATION.
AS FOR PRECIPITATION CHANCES THIS AFTERNOON INTO TONIGHT...THE
DEPTH OF THE CLOUDS INCREASE QUICKLY LATE THIS AFTERNOON INTO THE
EVENING. MARGINAL SATURATED ISENTROPIC ASCENT AND CONVERGENCE
AHEAD OF A COLD FRONT MOVING THROUGH...MAY OFFER SPORADIC LIGHT
RAIN OR DRIZZLE IN THE SOUTHEAST HALF OF THE FORECAST AREA DURING
THE LATE AFTERNOON AND EVENING. THE LIGHT RAIN MAY ACTUALLY BE
MORE SHOWERY...BUT LIMITED FORCING WILL PREVENT ANYTHING
APPRECIABLE.
WEDNESDAY AND THURSDAY...WHILE LOW-LEVEL TEMPERATURES ARE FORECAST
TO COOL DURING THIS PERIOD...THEY ARE STILL ON THE WARMER THAN
NORMAL SIDE. THE LACK OF SNOW COVER TOO SHOULD AID IN THE WARMER
BIAS-CORRECTED GUIDANCE BEING MORE ON TRACK. CLOUDS ALSO LOOK
LIMITED...ALTHOUGH CONFIDENCE IS CURRENTLY LOW ON WEDNESDAY
MORNING WITH A SOMEWHAT LIMITED SURGE BEHIND THIS FRONT MEANING
LINGERING STRATUS IS POSSIBLE. IF NOT THOUGH...TEMPERATURES
GETTING TO 50 ON WEDNESDAY SEEM PROBABLE...AND THEN WELL INTO THE
40S ON THURSDAY. RIDGING SHOULD ALLOW FOR ONLY CIRRUS BY THURSDAY.
LATE THIS WEEK INTO THE WEEKEND...THE PROGRESSIVE WESTERLY PATTERN
IS EXPECTED TO SLOW DOWN WITH A CUT OFF LOW AND A GENERAL BLOCKING
PATTERN DEVELOPING TO OUR WEST. DETAILS HAVE VARIED
SIGNIFICANTLY...BUT A CLEAR TREND IN THE GUIDANCE IS SLOWER WITH
PROGRESSING FORCING FOR PRECIPITATION EAST INTO OUR AREA. GIVEN
THAT PATTERN...THAT SEEMS REASONABLE AND HAVE ADJUSTED THE BLENDED
GUIDANCE FORECAST THAT WAY. THE SLOWER 31.00 EC WAS FOLLOWED
CLOSELY FOR DETAILS. SOME FORM OF INVERTED TROUGH OR WEAK SURFACE
LOW IS LIKELY TO DEVELOP AS THE CLOSED UPPER CIRCULATION WORKS
EAST...AND SUCH A FEATURE WOULD ALSO NOT FAVOR PRECIP FAR TO ITS
EAST. SO ONLY HAVE SMALL CHANCES DURING THE WEEKEND...WITH
FORECAST SOUNDINGS AND GENERAL THICKNESSES SLIGHTLY MORE
SUPPORTIVE OF RAIN THAN SNOW IF PRECIP OCCURS. IT IS STILL
FAVORED THAT NO PRECIPITATION WILL OCCUR THIS WEEKEND...ESPECIALLY
IF THE EC SOUTHERN TRACK OF THE CLOSED LOW WERE TO COME TO
FRUITION.
&&
.CLIMATE...
THE RECORD HIGH TODAY FOR CHICAGO IS 65 IN 1989. THE HIGH
TEMPERATURE IS MOST LIKELY TO BE 3 TO 7 DEGREES SHY OF THIS...BUT
IT COULD END UP GETTING VERY CLOSE. THE GOING FORECAST IS FOR THIS
TO BE THE WARMEST DAY THIS METEOROLOGICAL WINTER SO FAR. THIS WILL
BE THE TENTH DAY IN AT LEAST THE 50S SINCE DECEMBER 1ST /BASICALLY
ONE DAY A WEEK THIS WINTER SO FAR/. AS FOR ROCKFORD THE RECORD
HIGH IS 63 ALSO IN 1989. THE HIGH TEMPERATURE IS EXPECTED TO FALL
SEVERAL DEGREES SHORT...BUT CONFIDENCE IS LOWER AT ROCKFORD
DEPENDING ON HOW THE STRATUS EVOLVES IN /IT MAY REMAIN SOUTH OF
ROCKFORD/. THIS WILL BE THE NINTH DAY IN AT LEAST THE 50S THIS
METEOROLOGICAL WINTER AT ROCKFORD.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 16Z...
* SSWLY WINDS GUSTING TO 25KT VEERING SWLY THIS AFTERNOON.
* ANTICIPATED MVFR CIGS THIS AFTERNOON LOOKING LESS LIKELY.
KREIN
//DISCUSSION...UPDATED 12Z...
MORNING FORECAST HAS A FEW CHALLENGES. THE FIRST WILL BE WITH LLWS
LIKELIHOOD THROUGH THE EARLY MORNING HOURS. ORD/MDW 1 MINUTE ASOS
DATA HAS BEEN HAVING ON AND OFF GUSTS IN THE 17-20KT RANGE
OVERNIGHT...WITH SUSTAINED 10-15KT WINDS. 12Z SOUNDINGS FROM ILX
AND DVN MAINTAINED A GENERAL 55KT WIND OUT OF ROUGHLY 240 AT 1.9
KFT. EXPECT THE THREAT TO CONTINUE INTO THROUGH ROUGHLY 15Z OR SO
WHEN HIGHER SURFACE GUSTS BEGIN AND AS THE HIGHEST LOWER LEVEL
WINDS SHIFT EAST. A FRONT WILL MOVE ACROSS THE AIRSPACE LATE THIS
EVENING SHIFTING WINDS FROM WEST TO NORTHWEST.
THE SECOND CHALLENGE WILL BE WITH CLOUD COVER. CONTINUED RUN AFTER
RUN OF ALL FORECAST GUIDANCE HAS BEEN OVERDOING THE LOWEST LEVEL
RH FIELDS...AND BRINGING IN HIGH IFR TO LOW MVFR STRATUS ACROSS
THE EASTERN TERMINALS INTO THE LATE MORNING HOURS. STILL BELIEVE
THAT WE WILL SEE A HIGHER END MVFR TO LOWER END VFR CIG SWING
ACROSS THE REGION BEYOND THE 19Z HOUR TODAY. A MANUAL TIME OF
ARRIVAL OF THE PRESENT FIELD ACROSS NORTHWEST MISSOURI WOULD BRING
THE DECK INTO ORD BY 17Z...AND MET/MAV WOULD LEAD YOU TO BELIEVE
THAT THE TERMINALS WOULD SEE CIGS BELOW 015. DISCOUNTING THAT FOR
A FEW REASONS. FIRST IS DUE TO HIGHER RH BIAS THAT HAS BEEN
ONGOING...AND ALSO FEEL WITH DAYTIME MIXING...CIGS SHOULD BEGIN TO
RAISE. ALSO...H92-95 FLOW WILL TURN A LITTLE MORE WESTERLY THIS
MORNING...AND THE MAIN MOISTURE AXIS SHOULD TURN A LITTLE MORE
EASTERLY. WITH THE BULK OF THE MOISTURE STAYING TO THE SOUTH OF
ORD/MDW...FEEL THAT THE TERMINALS SHOULD NOT SEE ANY -DZ OUTSIDE
OF GYY...WHERE A LATE EVENING TIMING LOOKS BEST AT THIS
POINT...BUT CONFIDENCE REMAINS LOW ENOUGH THAT WILL ONLY CARRY A
PROB30 FOR LIGHT RAIN AT THIS POINT.
SHEA
//ORD AND MDW CONFIDENCE...UPDATED 16Z...
* MODERATE CONFIDENCE THAT CIGS WILL REMAIN VFR THROUGH EARLY
THIS EVENING UNTIL FROPA...LOWER CONFIDENCE IN CHANCES FOR MVFR
CIGS FOR A SHORT TIME AFTER FROPA.
* LOW CONFIDENCE IN -DZ POTENTIAL IN THE LATE AFTERNOON.
* MODERATE-HIGH CONFIDENCE ALL OTHER FORECAST ELEMENTS.
KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
* WEDNESDAY NIGHT THROUGH FRIDAY...VFR
* SATURDAY AND SUNDAY...SLIGHT CHANCE OF RAIN OR SNOW
* MONDAY...VFR
SHEA
&&
.MARINE...
253 AM...LOW PRESSURE OVER THE UPPER MIDWEST WILL MOVE ACROSS
LAKE SUPERIOR THIS AFTERNOON AND INTO QUEBEC WEDNESDAY MORNING.
A WARM FRONT EXTENDING ACROSS NORTH CENTRAL LAKE MICHIGAN THIS
MORNING WILL LIFT NORTH AS THE LOW APPROACHES AND THE GRADIENT
WILL ALSO CONTINUE TO TIGHTEN...FROM SOUTH TO NORTH AS THE LOW
APPROACHES. SOUTHERLY WINDS CONTINUE TO GUST AS HIGH AS 30 KTS
ACROSS FAR SOUTHERN LAKE MICHIGAN EARLY THIS MORNING AND EXPECT
THESE HIGHER WINDS/GUSTS TO CONTINUE NORTH DURING THE DAY. COULD
BE SOME HIGHER GUSTS TO 35 KT GALES BUT RATHER LOW CONFIDENCE
REGARDING HOW PREVAILING THESE MAY BECOME AND WILL NEED TO BE
MONITORED THROUGH THE MORNING.
A TRAILING COLD FRONT FROM THIS LOW WILL MOVE ACROSS THE LAKE
EARLY THIS EVENING... SHIFTING WINDS WESTERLY WITH 30 KTS
POSSIBLE BEHIND THE FRONT... ESPECIALLY ACROSS THE NORTH HALF OR
SO OF THE LAKE. BROAD HIGH PRESSURE WILL BUILD ACROSS THE PLAINS
TONIGHT INTO WEDNESDAY AND THEN ACROSS THE SOUTHERN GREAT LAKES
REGION WEDNESDAY AFTERNOON INTO THURSDAY. NEW LOW PRESSURE IS
EXPECTED TO DEVELOP OVER THE SOUTHERN PLAINS THURSDAY NIGHT INTO
FRIDAY AND THEN MOVE NORTHEAST ACROSS THE SOUTHERN LAKES THIS
WEEKEND. WHILE WINDS WILL SHIFT TO THE NORTHEAST AS THIS LOW
APPROACHES...THERE STILL REMAINS QUITE A BIT OF UNCERTAINTY
REGARDING THE TRACK...STRENGTHEN AND TIMING OF THIS SYSTEM. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 10 PM TUESDAY.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
823 AM CST TUE JAN 31 2012
.DISCUSSION...
317 AM CST
THE ATTENTION ON THIS FORECAST WAS PRIMARILY DIRECTED TO
TEMPERATURES...WITH AN EMPHASIS ON TODAY AS NEAR RECORD TO RECORD
WARMTH IS ON PAR AGAIN FOR THE AREA. QUITE A DIFFERENCE FROM ONE
YEAR AGO TODAY...WHICH SAW THE AREA PREPARING FOR THE THIRD
LARGEST SNOWSTORM ON RECORD. AN ADDITIONAL CHALLENGE IN THE
FORECAST IS THAT BOTH WEDNESDAY AND THURSDAY ALSO ARE APPEARING
LIKELY TO BE WARMER THAN INITIALLY THOUGHT.
TEMPERATURES ARE STARTING NEARLY 30 DEGREES ABOVE NORMAL THIS
FINAL DAY OF JANUARY...WHICH IS FITTING FOR THIS MONTH THAT IS
AVERAGING 5 TO 6 DEGREES ABOVE NORMAL. SOUTHERLY WINDS AND
INCREASING LOW-LEVEL MOISTURE THROUGHOUT LAST NIGHT INTO THIS
MORNING HAVE AIDED THESE MILD READINGS. THE ANTICIPATED
STRATUS/STRATOCU IS DEVELOPING QUICKLY NORTHEAST FROM THE SOUTHERN
PLAINS/OZARKS EARLY THIS MORNING...LINING UP WELL WITH MODEL
DIAGNOSTIC SOLUTIONS OF MOISTURE TRANSPORT AND CONVERGENCE IN THE
LOW LEVELS /ROUGHLY 850-925MB/.
EVEN AHEAD OF THESE LOW CLOUDS...MODEL GUIDANCE CONTINUES TO SHOW
BOTH A TOO MOIST AND COOL BIAS IN THE LOW-LEVELS...SOME LIKELY DUE
TO FALSE SNOW COVER AND/OR TOO COLD OF GROUND COVER. JUST THE
31.00 GFS AND NAMELY THE NAM SOUNDINGS ACROSS THE AREA REVEALED
THIS BIAS ALMOST IMMEDIATELY AFTER THEIR INITIALIZATION HOURS. SO
HAVE GUIDED MORE ON ABSOLUTE MOISTURE VALUES AND SATURATION NEAR
THE TOP OF THE ADAPTED MIXED-LAYER LATER THIS MORNING /~4000 FT/
FOR CLOUD INDICATIONS. THE MOISTURE CONVERGENCE FORECAST FROM THE
RUC AND NAM LINE UP WELL FROM SOUTHEAST IA INTO NORTHERN IL AND
EXPECT THE CLOUDS TO EXPAND INTO THAT AREA DURING THE LATE
MORNING. RUC PARCEL TRAJECTORIES WOULD INDICATE NEAR A 12 PM
ARRIVAL IN CHICAGO BASED ON CURRENT PLACEMENT OF THE LOW
CLOUDS...BUT SOME LEAD SATURATION MAY CAUSE IT TO BE A LITTLE
QUICKER. THE STRATUS PLUME AND HOW QUICKLY IT MOVES IN WILL LIKELY
IMPACT TEMPERATURES A FEW DEGREES.
AS FOR THOSE TEMPERATURES TODAY...LOCAL ANALYSIS HERE HAS SHOWN
THAT BIAS-CORRECTED GUIDANCE IS WORKING VERY WELL IN THESE VERY
MILD STRETCHES THIS WINTER...PARTICULARLY THE GEM AND THE EC. HAVE
BLENDED OUR GOING FORECAST HEAVILY TOWARDS THESE SOLUTIONS...AND
EVEN ADJUSTED UP FROM THERE IN SOME AREAS. WHILE THE CLOUDS WILL
EXPAND IN...CONTINUED LOW-LEVEL WARM ADVECTION WILL LIKELY
SUPPORT INCREASING SURFACE TEMPERATURES INTO THE
AFTERNOON...ALBEIT AT A SLOWER RATE. SO HAVE SOME QUICK MORNING
WARMING FORECAST FROM THE HIGH STARTING POINT VALUES...AND THEN
GRADUAL INCREASE THIS AFTERNOON. THIS APPROACH YIELDS REMARKABLY
MILD UPPER 50S TO LOWER 60 DEGREE READINGS BEING LIKELY IN SEVERAL
AREAS. EVEN MID 60S COULD BE TOUCHED IN THE EASTERN HALF OF THE
AREA IF THE RATE OF WARMING AFTER THE CLOUDS ARRIVE IS HIGHER THAN
INDICATED. PLEASE SEE THE CLIMATE SECTION BELOW FOR RECORD
INFORMATION.
AS FOR PRECIPITATION CHANCES THIS AFTERNOON INTO TONIGHT...THE
DEPTH OF THE CLOUDS INCREASE QUICKLY LATE THIS AFTERNOON INTO THE
EVENING. MARGINAL SATURATED ISENTROPIC ASCENT AND CONVERGENCE
AHEAD OF A COLD FRONT MOVING THROUGH...MAY OFFER SPORADIC LIGHT
RAIN OR DRIZZLE IN THE SOUTHEAST HALF OF THE FORECAST AREA DURING
THE LATE AFTERNOON AND EVENING. THE LIGHT RAIN MAY ACTUALLY BE
MORE SHOWERY...BUT LIMITED FORCING WILL PREVENT ANYTHING
APPRECIABLE.
WEDNESDAY AND THURSDAY...WHILE LOW-LEVEL TEMPERATURES ARE FORECAST
TO COOL DURING THIS PERIOD...THEY ARE STILL ON THE WARMER THAN
NORMAL SIDE. THE LACK OF SNOW COVER TOO SHOULD AID IN THE WARMER
BIAS-CORRECTED GUIDANCE BEING MORE ON TRACK. CLOUDS ALSO LOOK
LIMITED...ALTHOUGH CONFIDENCE IS CURRENTLY LOW ON WEDNESDAY
MORNING WITH A SOMEWHAT LIMITED SURGE BEHIND THIS FRONT MEANING
LINGERING STRATUS IS POSSIBLE. IF NOT THOUGH...TEMPERATURES
GETTING TO 50 ON WEDNESDAY SEEM PROBABLE...AND THEN WELL INTO THE
40S ON THURSDAY. RIDGING SHOULD ALLOW FOR ONLY CIRRUS BY THURSDAY.
LATE THIS WEEK INTO THE WEEKEND...THE PROGRESSIVE WESTERLY PATTERN
IS EXPECTED TO SLOW DOWN WITH A CUT OFF LOW AND A GENERAL BLOCKING
PATTERN DEVELOPING TO OUR WEST. DETAILS HAVE VARIED
SIGNIFICANTLY...BUT A CLEAR TREND IN THE GUIDANCE IS SLOWER WITH
PROGRESSING FORCING FOR PRECIPITATION EAST INTO OUR AREA. GIVEN
THAT PATTERN...THAT SEEMS REASONABLE AND HAVE ADJUSTED THE BLENDED
GUIDANCE FORECAST THAT WAY. THE SLOWER 31.00 EC WAS FOLLOWED
CLOSELY FOR DETAILS. SOME FORM OF INVERTED TROUGH OR WEAK SURFACE
LOW IS LIKELY TO DEVELOP AS THE CLOSED UPPER CIRCULATION WORKS
EAST...AND SUCH A FEATURE WOULD ALSO NOT FAVOR PRECIP FAR TO ITS
EAST. SO ONLY HAVE SMALL CHANCES DURING THE WEEKEND...WITH
FORECAST SOUNDINGS AND GENERAL THICKNESSES SLIGHTLY MORE
SUPPORTIVE OF RAIN THAN SNOW IF PRECIP OCCURS. IT IS STILL
FAVORED THAT NO PRECIPITATION WILL OCCUR THIS WEEKEND...ESPECIALLY
IF THE EC SOUTHERN TRACK OF THE CLOSED LOW WERE TO COME TO
FRUITION.
&&
.CLIMATE...
THE RECORD HIGH TODAY FOR CHICAGO IS 65 IN 1989. THE HIGH
TEMPERATURE IS MOST LIKELY TO BE 3 TO 7 DEGREES SHY OF THIS...BUT
IT COULD END UP GETTING VERY CLOSE. THE GOING FORECAST IS FOR THIS
TO BE THE WARMEST DAY THIS METEOROLOGICAL WINTER SO FAR. THIS WILL
BE THE TENTH DAY IN AT LEAST THE 50S SINCE DECEMBER 1ST /BASICALLY
ONE DAY A WEEK THIS WINTER SO FAR/. AS FOR ROCKFORD THE RECORD
HIGH IS 63 ALSO IN 1989. THE HIGH TEMPERATURE IS EXPECTED TO FALL
SEVERAL DEGREES SHORT...BUT CONFIDENCE IS LOWER AT ROCKFORD
DEPENDING ON HOW THE STRATUS EVOLVES IN /IT MAY REMAIN SOUTH OF
ROCKFORD/. THIS WILL BE THE NINTH DAY IN AT LEAST THE 50S THIS
METEOROLOGICAL WINTER AT ROCKFORD.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 14Z...
* LLWS THROUGH LATE MORNING.
* POSSIBLE MVFR CIGS IN STRATUS BY LATE MORNING/EARLY AFTERNOON.
KREIN
//DISCUSSION...UPDATED 12Z...
MORNING FORECAST HAS A FEW CHALLENGES. THE FIRST WILL BE WITH LLWS
LIKELIHOOD THROUGH THE EARLY MORNING HOURS. ORD/MDW 1 MINUTE ASOS
DATA HAS BEEN HAVING ON AND OFF GUSTS IN THE 17-20KT RANGE
OVERNIGHT...WITH SUSTAINED 10-15KT WINDS. 12Z SOUNDINGS FROM ILX
AND DVN MAINTAINED A GENERAL 55KT WIND OUT OF ROUGHLY 240 AT 1.9
KFT. EXPECT THE THREAT TO CONTINUE INTO THROUGH ROUGHLY 15Z OR SO
WHEN HIGHER SURFACE GUSTS BEGIN AND AS THE HIGHEST LOWER LEVEL
WINDS SHIFT EAST. A FRONT WILL MOVE ACROSS THE AIRSPACE LATE THIS
EVENING SHIFTING WINDS FROM WEST TO NORTHWEST.
THE SECOND CHALLENGE WILL BE WITH CLOUD COVER. CONTINUED RUN AFTER
RUN OF ALL FORECAST GUIDANCE HAS BEEN OVERDOING THE LOWEST LEVEL
RH FIELDS...AND BRINGING IN HIGH IFR TO LOW MVFR STRATUS ACROSS
THE EASTERN TERMINALS INTO THE LATE MORNING HOURS. STILL BELIEVE
THAT WE WILL SEE A HIGHER END MVFR TO LOWER END VFR CIG SWING
ACROSS THE REGION BEYOND THE 19Z HOUR TODAY. A MANUAL TIME OF
ARRIVAL OF THE PRESENT FIELD ACROSS NORTHWEST MISSOURI WOULD BRING
THE DECK INTO ORD BY 17Z...AND MET/MAV WOULD LEAD YOU TO BELIEVE
THAT THE TERMINALS WOULD SEE CIGS BELOW 015. DISCOUNTING THAT FOR
A FEW REASONS. FIRST IS DUE TO HIGHER RH BIAS THAT HAS BEEN
ONGOING...AND ALSO FEEL WITH DAYTIME MIXING...CIGS SHOULD BEGIN TO
RAISE. ALSO...H92-95 FLOW WILL TURN A LITTLE MORE WESTERLY THIS
MORNING...AND THE MAIN MOISTURE AXIS SHOULD TURN A LITTLE MORE
EASTERLY. WITH THE BULK OF THE MOISTURE STAYING TO THE SOUTH OF
ORD/MDW...FEEL THAT THE TERMINALS SHOULD NOT SEE ANY -DZ OUTSIDE
OF GYY...WHERE A LATE EVENING TIMING LOOKS BEST AT THIS
POINT...BUT CONFIDENCE REMAINS LOW ENOUGH THAT WILL ONLY CARRY A
PROB30 FOR LIGHT RAIN AT THIS POINT.
SHEA
//ORD AND MDW CONFIDENCE...UPDATED 14Z...
* HIGH CONFIDENCE IN LLWS FORECAST THROUGH THE MORNING
* MODERATE CONFIDENCE IN CIG TRENDS
* LOW CONFIDENCE IN -DZ POTENTIAL IN THE LATE AFTERNOON
* MODERATE-HIGH CONFIDENCE ALL OTHER FORECAST ELEMENTS
SHEA/KREIN
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
* WEDNESDAY NIGHT THROUGH FRIDAY...VFR
* SATURDAY AND SUNDAY...SLIGHT CHANCE OF RAIN OR SNOW
* MONDAY...VFR
SHEA
&&
.MARINE...
253 AM...LOW PRESSURE OVER THE UPPER MIDWEST WILL MOVE ACROSS
LAKE SUPERIOR THIS AFTERNOON AND INTO QUEBEC WEDNESDAY MORNING.
A WARM FRONT EXTENDING ACROSS NORTH CENTRAL LAKE MICHIGAN THIS
MORNING WILL LIFT NORTH AS THE LOW APPROACHES AND THE GRADIENT
WILL ALSO CONTINUE TO TIGHTEN...FROM SOUTH TO NORTH AS THE LOW
APPROACHES. SOUTHERLY WINDS CONTINUE TO GUST AS HIGH AS 30 KTS
ACROSS FAR SOUTHERN LAKE MICHIGAN EARLY THIS MORNING AND EXPECT
THESE HIGHER WINDS/GUSTS TO CONTINUE NORTH DURING THE DAY. COULD
BE SOME HIGHER GUSTS TO 35 KT GALES BUT RATHER LOW CONFIDENCE
REGARDING HOW PREVAILING THESE MAY BECOME AND WILL NEED TO BE
MONITORED THROUGH THE MORNING.
A TRAILING COLD FRONT FROM THIS LOW WILL MOVE ACROSS THE LAKE
EARLY THIS EVENING... SHIFTING WINDS WESTERLY WITH 30 KTS
POSSIBLE BEHIND THE FRONT... ESPECIALLY ACROSS THE NORTH HALF OR
SO OF THE LAKE. BROAD HIGH PRESSURE WILL BUILD ACROSS THE PLAINS
TONIGHT INTO WEDNESDAY AND THEN ACROSS THE SOUTHERN GREAT LAKES
REGION WEDNESDAY AFTERNOON INTO THURSDAY. NEW LOW PRESSURE IS
EXPECTED TO DEVELOP OVER THE SOUTHERN PLAINS THURSDAY NIGHT INTO
FRIDAY AND THEN MOVE NORTHEAST ACROSS THE SOUTHERN LAKES THIS
WEEKEND. WHILE WINDS WILL SHIFT TO THE NORTHEAST AS THIS LOW
APPROACHES...THERE STILL REMAINS QUITE A BIT OF UNCERTAINTY
REGARDING THE TRACK...STRENGTHEN AND TIMING OF THIS SYSTEM. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 10 PM TUESDAY.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
621 AM CST TUE JAN 31 2012
.DISCUSSION...
317 AM CST
THE ATTENTION ON THIS FORECAST WAS PRIMARILY DIRECTED TO
TEMPERATURES...WITH AN EMPHASIS ON TODAY AS NEAR RECORD TO RECORD
WARMTH IS ON PAR AGAIN FOR THE AREA. QUITE A DIFFERENCE FROM ONE
YEAR AGO TODAY...WHICH SAW THE AREA PREPARING FOR THE THIRD
LARGEST SNOWSTORM ON RECORD. AN ADDITIONAL CHALLENGE IN THE
FORECAST IS THAT BOTH WEDNESDAY AND THURSDAY ALSO ARE APPEARING
LIKELY TO BE WARMER THAN INITIALLY THOUGHT.
TEMPERATURES ARE STARTING NEARLY 30 DEGREES ABOVE NORMAL THIS
FINAL DAY OF JANUARY...WHICH IS FITTING FOR THIS MONTH THAT IS
AVERAGING 5 TO 6 DEGREES ABOVE NORMAL. SOUTHERLY WINDS AND
INCREASING LOW-LEVEL MOISTURE THROUGHOUT LAST NIGHT INTO THIS
MORNING HAVE AIDED THESE MILD READINGS. THE ANTICIPATED
STRATUS/STRATOCU IS DEVELOPING QUICKLY NORTHEAST FROM THE SOUTHERN
PLAINS/OZARKS EARLY THIS MORNING...LINING UP WELL WITH MODEL
DIAGNOSTIC SOLUTIONS OF MOISTURE TRANSPORT AND CONVERGENCE IN THE
LOW LEVELS /ROUGHLY 850-925MB/.
EVEN AHEAD OF THESE LOW CLOUDS...MODEL GUIDANCE CONTINUES TO SHOW
BOTH A TOO MOIST AND COOL BIAS IN THE LOW-LEVELS...SOME LIKELY DUE
TO FALSE SNOW COVER AND/OR TOO COLD OF GROUND COVER. JUST THE
31.00 GFS AND NAMELY THE NAM SOUNDINGS ACROSS THE AREA REVEALED
THIS BIAS ALMOST IMMEDIATELY AFTER THEIR INITIALIZATION HOURS. SO
HAVE GUIDED MORE ON ABSOLUTE MOISTURE VALUES AND SATURATION NEAR
THE TOP OF THE ADAPTED MIXED-LAYER LATER THIS MORNING /~4000 FT/
FOR CLOUD INDICATIONS. THE MOISTURE CONVERGENCE FORECAST FROM THE
RUC AND NAM LINE UP WELL FROM SOUTHEAST IA INTO NORTHERN IL AND
EXPECT THE CLOUDS TO EXPAND INTO THAT AREA DURING THE LATE
MORNING. RUC PARCEL TRAJECTORIES WOULD INDICATE NEAR A 12 PM
ARRIVAL IN CHICAGO BASED ON CURRENT PLACEMENT OF THE LOW
CLOUDS...BUT SOME LEAD SATURATION MAY CAUSE IT TO BE A LITTLE
QUICKER. THE STRATUS PLUME AND HOW QUICKLY IT MOVES IN WILL LIKELY
IMPACT TEMPERATURES A FEW DEGREES.
AS FOR THOSE TEMPERATURES TODAY...LOCAL ANALYSIS HERE HAS SHOWN
THAT BIAS-CORRECTED GUIDANCE IS WORKING VERY WELL IN THESE VERY
MILD STRETCHES THIS WINTER...PARTICULARLY THE GEM AND THE EC. HAVE
BLENDED OUR GOING FORECAST HEAVILY TOWARDS THESE SOLUTIONS...AND
EVEN ADJUSTED UP FROM THERE IN SOME AREAS. WHILE THE CLOUDS WILL
EXPAND IN...CONTINUED LOW-LEVEL WARM ADVECTION WILL LIKELY
SUPPORT INCREASING SURFACE TEMPERATURES INTO THE
AFTERNOON...ALBEIT AT A SLOWER RATE. SO HAVE SOME QUICK MORNING
WARMING FORECAST FROM THE HIGH STARTING POINT VALUES...AND THEN
GRADUAL INCREASE THIS AFTERNOON. THIS APPROACH YIELDS REMARKABLY
MILD UPPER 50S TO LOWER 60 DEGREE READINGS BEING LIKELY IN SEVERAL
AREAS. EVEN MID 60S COULD BE TOUCHED IN THE EASTERN HALF OF THE
AREA IF THE RATE OF WARMING AFTER THE CLOUDS ARRIVE IS HIGHER THAN
INDICATED. PLEASE SEE THE CLIMATE SECTION BELOW FOR RECORD
INFORMATION.
AS FOR PRECIPITATION CHANCES THIS AFTERNOON INTO TONIGHT...THE
DEPTH OF THE CLOUDS INCREASE QUICKLY LATE THIS AFTERNOON INTO THE
EVENING. MARGINAL SATURATED ISENTROPIC ASCENT AND CONVERGENCE
AHEAD OF A COLD FRONT MOVING THROUGH...MAY OFFER SPORADIC LIGHT
RAIN OR DRIZZLE IN THE SOUTHEAST HALF OF THE FORECAST AREA DURING
THE LATE AFTERNOON AND EVENING. THE LIGHT RAIN MAY ACTUALLY BE
MORE SHOWERY...BUT LIMITED FORCING WILL PREVENT ANYTHING
APPRECIABLE.
WEDNESDAY AND THURSDAY...WHILE LOW-LEVEL TEMPERATURES ARE FORECAST
TO COOL DURING THIS PERIOD...THEY ARE STILL ON THE WARMER THAN
NORMAL SIDE. THE LACK OF SNOW COVER TOO SHOULD AID IN THE WARMER
BIAS-CORRECTED GUIDANCE BEING MORE ON TRACK. CLOUDS ALSO LOOK
LIMITED...ALTHOUGH CONFIDENCE IS CURRENTLY LOW ON WEDNESDAY
MORNING WITH A SOMEWHAT LIMITED SURGE BEHIND THIS FRONT MEANING
LINGERING STRATUS IS POSSIBLE. IF NOT THOUGH...TEMPERATURES
GETTING TO 50 ON WEDNESDAY SEEM PROBABLE...AND THEN WELL INTO THE
40S ON THURSDAY. RIDGING SHOULD ALLOW FOR ONLY CIRRUS BY THURSDAY.
LATE THIS WEEK INTO THE WEEKEND...THE PROGRESSIVE WESTERLY PATTERN
IS EXPECTED TO SLOW DOWN WITH A CUT OFF LOW AND A GENERAL BLOCKING
PATTERN DEVELOPING TO OUR WEST. DETAILS HAVE VARIED
SIGNIFICANTLY...BUT A CLEAR TREND IN THE GUIDANCE IS SLOWER WITH
PROGRESSING FORCING FOR PRECIPITATION EAST INTO OUR AREA. GIVEN
THAT PATTERN...THAT SEEMS REASONABLE AND HAVE ADJUSTED THE BLENDED
GUIDANCE FORECAST THAT WAY. THE SLOWER 31.00 EC WAS FOLLOWED
CLOSELY FOR DETAILS. SOME FORM OF INVERTED TROUGH OR WEAK SURFACE
LOW IS LIKELY TO DEVELOP AS THE CLOSED UPPER CIRCULATION WORKS
EAST...AND SUCH A FEATURE WOULD ALSO NOT FAVOR PRECIP FAR TO ITS
EAST. SO ONLY HAVE SMALL CHANCES DURING THE WEEKEND...WITH
FORECAST SOUNDINGS AND GENERAL THICKNESSES SLIGHTLY MORE
SUPPORTIVE OF RAIN THAN SNOW IF PRECIP OCCURS. IT IS STILL
FAVORED THAT NO PRECIPITATION WILL OCCUR THIS WEEKEND...ESPECIALLY
IF THE EC SOUTHERN TRACK OF THE CLOSED LOW WERE TO COME TO
FRUITION.
&&
.CLIMATE...
THE RECORD HIGH TODAY FOR CHICAGO IS 65 IN 1989. THE HIGH
TEMPERATURE IS MOST LIKELY TO BE 3 TO 7 DEGREES SHY OF THIS...BUT
IT COULD END UP GETTING VERY CLOSE. THE GOING FORECAST IS FOR THIS
TO BE THE WARMEST DAY THIS METEOROLOGICAL WINTER SO FAR. THIS WILL
BE THE TENTH DAY IN AT LEAST THE 50S SINCE DECEMBER 1ST /BASICALLY
ONE DAY A WEEK THIS WINTER SO FAR/. AS FOR ROCKFORD THE RECORD
HIGH IS 63 ALSO IN 1989. THE HIGH TEMPERATURE IS EXPECTED TO FALL
SEVERAL DEGREES SHORT...BUT CONFIDENCE IS LOWER AT ROCKFORD
DEPENDING ON HOW THE STRATUS EVOLVES IN /IT MAY REMAIN SOUTH OF
ROCKFORD/. THIS WILL BE THE NINTH DAY IN AT LEAST THE 50S THIS
METEOROLOGICAL WINTER AT ROCKFORD.
MTF
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 12Z...
* MORNING LLWS
* LATE MORNING MVFR STRATUS POTENTIAL
SHEA
//DISCUSSION...UPDATED 12Z...
MORNING FORECAST HAS A FEW CHALLENGES. THE FIRST WILL BE WITH LLWS
LIKELIHOOD THROUGH THE EARLY MORNING HOURS. ORD/MDW 1 MINUTE ASOS
DATA HAS BEEN HAVING ON AND OFF GUSTS IN THE 17-20KT RANGE
OVERNIGHT...WITH SUSTAINED 10-15KT WINDS. 12Z SOUNDINGS FROM ILX
AND DVN MAINTAINED A GENERAL 55KT WIND OUT OF ROUGHLY 240 AT 1.9
KFT. EXPECT THE THREAT TO CONTINUE INTO THROUGH ROUGHLY 15Z OR SO
WHEN HIGHER SURFACE GUSTS BEGIN AND AS THE HIGHEST LOWER LEVEL
WINDS SHIFT EAST. A FRONT WILL MOVE ACROSS THE AIRSPACE LATE THIS
EVENING SHIFTING WINDS FROM WEST TO NORTHWEST.
THE SECOND CHALLENGE WILL BE WITH CLOUD COVER. CONTINUED RUN AFTER
RUN OF ALL FORECAST GUIDANCE HAS BEEN OVERDOING THE LOWEST LEVEL
RH FIELDS...AND BRINGING IN HIGH IFR TO LOW MVFR STRATUS ACROSS
THE EASTERN TERMINALS INTO THE LATE MORNING HOURS. STILL BELIEVE
THAT WE WILL SEE A HIGHER END MVFR TO LOWER END VFR CIG SWING
ACROSS THE REGION BEYOND THE 19Z HOUR TODAY. A MANUAL TIME OF
ARRIVAL OF THE PRESENT FIELD ACROSS NORTHWEST MISSOURI WOULD BRING
THE DECK INTO ORD BY 17Z...AND MET/MAV WOULD LEAD YOU TO BELIEVE
THAT THE TERMINALS WOULD SEE CIGS BELOW 015. DISCOUNTING THAT FOR
A FEW REASONS. FIRST IS DUE TO HIGHER RH BIAS THAT HAS BEEN
ONGOING...AND ALSO FEEL WITH DAYTIME MIXING...CIGS SHOULD BEGIN TO
RAISE. ALSO...H92-95 FLOW WILL TURN A LITTLE MORE WESTERLY THIS
MORNING...AND THE MAIN MOISTURE AXIS SHOULD TURN A LITTLE MORE
EASTERLY. WITH THE BULK OF THE MOISTURE STAYING TO THE SOUTH OF
ORD/MDW...FEEL THAT THE TERMINALS SHOULD NOT SEE ANY -DZ OUTSIDE
OF GYY...WHERE A LATE EVENING TIMING LOOKS BEST AT THIS
POINT...BUT CONFIDENCE REMAINS LOW ENOUGH THAT WILL ONLY CARRY A
PROB30 FOR LIGHT RAIN AT THIS POINT.
SHEA
//ORD AND MDW CONFIDENCE...UPDATED 12Z...
* HIGH CONFIDENCE IN LLWS FORECAST THROUGH THE MORNING
* MODERATE CONFIDENCE IN CIG TRENDS
* LOW CONFIDENCE IN -DZ POTENTIAL IN THE LATE AFTERNOON
* MODERATE-HIGH CONFIDENCE ALL OTHER FORECAST ELEMENTS
SHEA
//OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z...
* WEDNESDAY NIGHT THROUGH FRIDAY...VFR
* SATURDAY AND SUNDAY...SLIGHT CHANCE OF RAIN OR SNOW
* MONDAY...VFR
SHEA
&&
.MARINE...
253 AM...LOW PRESSURE OVER THE UPPER MIDWEST WILL MOVE ACROSS
LAKE SUPERIOR THIS AFTERNOON AND INTO QUEBEC WEDNESDAY MORNING.
A WARM FRONT EXTENDING ACROSS NORTH CENTRAL LAKE MICHIGAN THIS
MORNING WILL LIFT NORTH AS THE LOW APPROACHES AND THE GRADIENT
WILL ALSO CONTINUE TO TIGHTEN...FROM SOUTH TO NORTH AS THE LOW
APPROACHES. SOUTHERLY WINDS CONTINUE TO GUST AS HIGH AS 30 KTS
ACROSS FAR SOUTHERN LAKE MICHIGAN EARLY THIS MORNING AND EXPECT
THESE HIGHER WINDS/GUSTS TO CONTINUE NORTH DURING THE DAY. COULD
BE SOME HIGHER GUSTS TO 35 KT GALES BUT RATHER LOW CONFIDENCE
REGARDING HOW PREVAILING THESE MAY BECOME AND WILL NEED TO BE
MONITORED THROUGH THE MORNING.
A TRAILING COLD FRONT FROM THIS LOW WILL MOVE ACROSS THE LAKE
EARLY THIS EVENING... SHIFTING WINDS WESTERLY WITH 30 KTS
POSSIBLE BEHIND THE FRONT... ESPECIALLY ACROSS THE NORTH HALF OR
SO OF THE LAKE. BROAD HIGH PRESSURE WILL BUILD ACROSS THE PLAINS
TONIGHT INTO WEDNESDAY AND THEN ACROSS THE SOUTHERN GREAT LAKES
REGION WEDNESDAY AFTERNOON INTO THURSDAY. NEW LOW PRESSURE IS
EXPECTED TO DEVELOP OVER THE SOUTHERN PLAINS THURSDAY NIGHT INTO
FRIDAY AND THEN MOVE NORTHEAST ACROSS THE SOUTHERN LAKES THIS
WEEKEND. WHILE WINDS WILL SHIFT TO THE NORTHEAST AS THIS LOW
APPROACHES...THERE STILL REMAINS QUITE A BIT OF UNCERTAINTY
REGARDING THE TRACK...STRENGTHEN AND TIMING OF THIS SYSTEM. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 10 PM TUESDAY.
&&
$$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
319 AM CST TUE JAN 31 2012
.DISCUSSION...
317 AM CST
THE ATTENTION ON THIS FORECAST WAS PRIMARILY DIRECTED TO
TEMPERATURES...WITH AN EMPHASIS ON TODAY AS NEAR RECORD TO RECORD
WARMTH IS ON PAR AGAIN FOR THE AREA. QUITE A DIFFERENCE FROM ONE
YEAR AGO TODAY...WHICH SAW THE AREA PREPARING FOR THE THIRD
LARGEST SNOWSTORM ON RECORD. AN ADDITIONAL CHALLENGE IN THE
FORECAST IS THAT BOTH WEDNESDAY AND THURSDAY ALSO ARE APPEARING
LIKELY TO BE WARMER THAN INITIALLY THOUGHT.
TEMPERATURES ARE STARTING NEARLY 30 DEGREES ABOVE NORMAL THIS
FINAL DAY OF JANUARY...WHICH IS FITTING FOR THIS MONTH THAT IS
AVERAGING 5 TO 6 DEGREES ABOVE NORMAL. SOUTHERLY WINDS AND
INCREASING LOW-LEVEL MOISTURE THROUGHOUT LAST NIGHT INTO THIS
MORNING HAVE AIDED THESE MILD READINGS. THE ANTICIPATED
STRATUS/STRATOCU IS DEVELOPING QUICKLY NORTHEAST FROM THE SOUTHERN
PLAINS/OZARKS EARLY THIS MORNING...LINING UP WELL WITH MODEL
DIAGNOSTIC SOLUTIONS OF MOISTURE TRANSPORT AND CONVERGENCE IN THE
LOW LEVELS /ROUGHLY 850-925MB/.
EVEN AHEAD OF THESE LOW CLOUDS...MODEL GUIDANCE CONTINUES TO SHOW
BOTH A TOO MOIST AND COOL BIAS IN THE LOW-LEVELS...SOME LIKELY DUE
TO FALSE SNOW COVER AND/OR TOO COLD OF GROUND COVER. JUST THE
31.00 GFS AND NAMELY THE NAM SOUNDINGS ACROSS THE AREA REVEALED
THIS BIAS ALMOST IMMEDIATELY AFTER THEIR INITIALIZATION HOURS. SO
HAVE GUIDED MORE ON ABSOLUTE MOISTURE VALUES AND SATURATION NEAR
THE TOP OF THE ADAPTED MIXED-LAYER LATER THIS MORNING /~4000 FT/
FOR CLOUD INDICATIONS. THE MOISTURE CONVERGENCE FORECAST FROM THE
RUC AND NAM LINE UP WELL FROM SOUTHEAST IA INTO NORTHERN IL AND
EXPECT THE CLOUDS TO EXPAND INTO THAT AREA DURING THE LATE
MORNING. RUC PARCEL TRAJECTORIES WOULD INDICATE NEAR A 12 PM
ARRIVAL IN CHICAGO BASED ON CURRENT PLACEMENT OF THE LOW
CLOUDS...BUT SOME LEAD SATURATION MAY CAUSE IT TO BE A LITTLE
QUICKER. THE STRATUS PLUME AND HOW QUICKLY IT MOVES IN WILL LIKELY
IMPACT TEMPERATURES A FEW DEGREES.
AS FOR THOSE TEMPERATURES TODAY...LOCAL ANALYSIS HERE HAS SHOWN
THAT BIAS-CORRECTED GUIDANCE IS WORKING VERY WELL IN THESE VERY
MILD STRETCHES THIS WINTER...PARTICULARLY THE GEM AND THE EC. HAVE
BLENDED OUR GOING FORECAST HEAVILY TOWARDS THESE SOLUTIONS...AND
EVEN ADJUSTED UP FROM THERE IN SOME AREAS. WHILE THE CLOUDS WILL
EXPAND IN...CONTINUED LOW-LEVEL WARM ADVECTION WILL LIKELY
SUPPORT INCREASING SURFACE TEMPERATURES INTO THE
AFTERNOON...ALBEIT AT A SLOWER RATE. SO HAVE SOME QUICK MORNING
WARMING FORECAST FROM THE HIGH STARTING POINT VALUES...AND THEN
GRADUAL INCREASE THIS AFTERNOON. THIS APPROACH YIELDS REMARKABLY
MILD UPPER 50S TO LOWER 60 DEGREE READINGS BEING LIKELY IN SEVERAL
AREAS. EVEN MID 60S COULD BE TOUCHED IN THE EASTERN HALF OF THE
AREA IF THE RATE OF WARMING AFTER THE CLOUDS ARRIVE IS HIGHER THAN
INDICATED. PLEASE SEE THE CLIMATE SECTION BELOW FOR RECORD
INFORMATION.
AS FOR PRECIPITATION CHANCES THIS AFTERNOON INTO TONIGHT...THE
DEPTH OF THE CLOUDS INCREASE QUICKLY LATE THIS AFTERNOON INTO THE
EVENING. MARGINAL SATURATED ISENTROPIC ASCENT AND CONVERGENCE
AHEAD OF A COLD FRONT MOVING THROUGH...MAY OFFER SPORADIC LIGHT
RAIN OR DRIZZLE IN THE SOUTHEAST HALF OF THE FORECAST AREA DURING
THE LATE AFTERNOON AND EVENING. THE LIGHT RAIN MAY ACTUALLY BE
MORE SHOWERY...BUT LIMITED FORCING WILL PREVENT ANYTHING
APPRECIABLE.
WEDNESDAY AND THURSDAY...WHILE LOW-LEVEL TEMPERATURES ARE FORECAST
TO COOL DURING THIS PERIOD...THEY ARE STILL ON THE WARMER THAN
NORMAL SIDE. THE LACK OF SNOW COVER TOO SHOULD AID IN THE WARMER
BIAS-CORRECTED GUIDANCE BEING MORE ON TRACK. CLOUDS ALSO LOOK
LIMITED...ALTHOUGH CONFIDENCE IS CURRENTLY LOW ON WEDNESDAY
MORNING WITH A SOMEWHAT LIMITED SURGE BEHIND THIS FRONT MEANING
LINGERING STRATUS IS POSSIBLE. IF NOT THOUGH...TEMPERATURES
GETTING TO 50 ON WEDNESDAY SEEM PROBABLE...AND THEN WELL INTO THE
40S ON THURSDAY. RIDGING SHOULD ALLOW FOR ONLY CIRRUS BY THURSDAY.
LATE THIS WEEK INTO THE WEEKEND...THE PROGRESSIVE WESTERLY PATTERN
IS EXPECTED TO SLOW DOWN WITH A CUT OFF LOW AND A GENERAL BLOCKING
PATTERN DEVELOPING TO OUR WEST. DETAILS HAVE VARIED
SIGNIFICANTLY...BUT A CLEAR TREND IN THE GUIDANCE IS SLOWER WITH
PROGRESSING FORCING FOR PRECIPITATION EAST INTO OUR AREA. GIVEN
THAT PATTERN...THAT SEEMS REASONABLE AND HAVE ADJUSTED THE BLENDED
GUIDANCE FORECAST THAT WAY. THE SLOWER 31.00 EC WAS FOLLOWED
CLOSELY FOR DETAILS. SOME FORM OF INVERTED TROUGH OR WEAK SURFACE
LOW IS LIKELY TO DEVELOP AS THE CLOSED UPPER CIRCULATION WORKS
EAST...AND SUCH A FEATURE WOULD ALSO NOT FAVOR PRECIP FAR TO ITS
EAST. SO ONLY HAVE SMALL CHANCES DURING THE WEEKEND...WITH
FORECAST SOUNDINGS AND GENERAL THICKNESSES SLIGHTLY MORE
SUPPORTIVE OF RAIN THAN SNOW IF PRECIP OCCURS. IT IS STILL
FAVORED THAT NO PRECIPITATION WILL OCCUR THIS WEEKEND...ESPECIALLY
IF THE EC SOUTHERN TRACK OF THE CLOSED LOW WERE TO COME TO
FRUITION.
&&
.CLIMATE...
THE RECORD HIGH TODAY FOR CHICAGO IS 65 IN 1989. THE HIGH
TEMPERATURE IS MOST LIKELY TO BE 3 TO 7 DEGREES SHY OF THIS...BUT
IT COULD END UP GETTING VERY CLOSE. THE GOING FORECAST IS FOR THIS
TO BE THE WARMEST DAY THIS METEOROLOGICAL WINTER SO FAR. THIS WILL
BE THE TENTH DAY IN AT LEAST THE 50S SINCE DECEMBER 1ST /BASICALLY
ONE DAY A WEEK THIS WINTER SO FAR/. AS FOR ROCKFORD THE RECORD
HIGH IS 63 ALSO IN 1989. THE HIGH TEMPERATURE IS EXPECTED TO FALL
SEVERAL DEGREES SHORT...BUT CONFIDENCE IS LOWER AT ROCKFORD
DEPENDING ON HOW THE STRATUS EVOLVES IN /IT MAY REMAIN SOUTH OF
ROCKFORD/. THIS WILL BE THE NINTH DAY IN AT LEAST THE 50S THIS
METEOROLOGICAL WINTER AT ROCKFORD.
MTF
&&
.CLIMATE...
RECORD HIGHS FOR JANUARY 30...
* CHICAGO....55 SET IN 1988
* ROCKFORD...52 TIED IN 1944 AND 1926
RECORD HIGHS FOR JANUARY 31...
* CHICAGO....65 SET IN 1989
* ROCKFORD...63 SET IN 1989 /ALSO THE HIGHEST JANUARY RECORDED/
&&
.AVIATION...
//ORD AND MDW CONCERNS...UPDATED 08Z...
* LLWS THROUGH EARLY MORNING
* GUSTY SSW WINDS MID MORNING THROUGH AFTERNOON
* MVFR CIGS PROBABLE TUESDAY AFTERNOON
SHEA
//DISCUSSION...UPDATED 06Z...
LLWS REMAINS LIKELY THROUGH EARLY TUES MORNING AS STRONG LOW LEVEL
JET PERSISTS ABOVE NOCTURNAL INVERSION RIGHT OFF THE DECK. RECENT
ACARS SOUNDINGS OUT OF ORD SHOW 55KT+ WINDS WITHIN 1500 FT AGL NOW
SO HAVE BUMPED UP THE MAGNITUDE OF THE LLWS IN THE TAFS. BY MID
MORNING TUESDAY THREAT OF LLWS SHOULD SUBSIDE AND TRANSITION MORE
TO LOW LEVEL TURBULENCE AS SURFACE WARMS AND MIXING BEGINS TO
TRANSPORT SOME OF THAT HIGHER MOMENTUM AIR TO THE SURFACE IN
GUSTS. EXPECT SSW WINDS TO GUST TO AT LEAST 25KT BY MID-LATE
MORNING...THOUGH COULD SEE GUSTS BEGIN TO WANE A BIT DURING THE
AFTERNOON IF STRATUS DECK MOVES IN.
SPEAKING OF STRATUS...MODELS REMAIN OBLIVIOUS TO WHAT BOUNDARY
LAYER CONDITIONS ARE ACTUALLY LIKE AND CONTINUE TO UNREALISTICALLY
COOL AND SATURATE THE BOUNDARY LAYER MAKING FORECAST SOUNDINGS
USELESS. SATELLITE IMAGERY DOES SHOW LOW LEVEL MOISTURE AND
STRATUS OVER ARKLATEX REGION BEGINNING TO DEVELOP AND ADVECT
NORTHWARD. ANTICIPATE THIS TREND TO CONTINUE AND PROBABLY
ACCELERATE A BIT OVERNIGHT AS LOW LEVEL JET PULLS THE MOISTURE
NORTHWARD. BASED ON OBS WELL UPSTREAM AND EXPECTATION OF VERY WARM
CONDITIONS WOULD ANTICIPATE BASES OF ANY STRATUS OR STRATOCUMULUS
DECK TO BE MORE IN THE HIGHER END MVFR/LOW END VFR RANGE. GIVEN
THE TRAJECTORY OF THE LOW LEVEL FLOW ITS POSSIBLE THAT THE BRUNT
OF THE NORTHWARD SURGING STRATUS COULD END UP MISSING CHICAGO JUST
TO THE SOUTHEAST...BUT WITH SO MUCH UNCERTAINTY HAVE MAINTAIN IDEA
OF PREVIOUS TAFS WITH MVFR CIGS TUES AFTERNOON.
WINDS SHIFT TO MORE WESTERLY DIRECTION WITH DRIER AIR MOVING IN
AND ANY STRATUS THAT DOES DEVELOP WOULD MOST LIKELY BE SHOVED EAST
IN THE WAKE OF THE WEAK FRONTAL PASSAGE TUESDAY EVENING.
IZZI
//ORD AND MDW CONFIDENCE...UPDATED 08Z...
* LOW CONFIDENCE ON CIG TRENDS
* LOW CONFIDENCE ON ANY -DZ LATE AFTERNOON
* HIGH CONFIDENCE ALL OTHER FORECAST ELEMENTS
SHEA
//OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z...
WEDNESDAY...MVFR CIGS POSSIBLE EARLY.
THURSDAY AND FRIDAY...VFR.
SATURDAY AND SUNDAY...SLIGHT CHANCE OF RAIN OR SNOW.
IZZI
&&
.MARINE...
253 AM...LOW PRESSURE OVER THE UPPER MIDWEST WILL MOVE ACROSS
LAKE SUPERIOR THIS AFTERNOON AND INTO QUEBEC WEDNESDAY MORNING.
A WARM FRONT EXTENDING ACROSS NORTH CENTRAL LAKE MICHIGAN THIS
MORNING WILL LIFT NORTH AS THE LOW APPROACHES AND THE GRADIENT
WILL ALSO CONTINUE TO TIGHTEN...FROM SOUTH TO NORTH AS THE LOW
APPROACHES. SOUTHERLY WINDS CONTINUE TO GUST AS HIGH AS 30 KTS
ACROSS FAR SOUTHERN LAKE MICHIGAN EARLY THIS MORNING AND EXPECT
THESE HIGHER WINDS/GUSTS TO CONTINUE NORTH DURING THE DAY. COULD
BE SOME HIGHER GUSTS TO 35 KT GALES BUT RATHER LOW CONFIDENCE
REGARDING HOW PREVAILING THESE MAY BECOME AND WILL NEED TO BE
MONITORED THROUGH THE MORNING.
A TRAILING COLD FRONT FROM THIS LOW WILL MOVE ACROSS THE LAKE
EARLY THIS EVENING... SHIFTING WINDS WESTERLY WITH 30 KTS
POSSIBLE BEHIND THE FRONT... ESPECIALLY ACROSS THE NORTH HALF OR
SO OF THE LAKE. BROAD HIGH PRESSURE WILL BUILD ACROSS THE PLAINS
TONIGHT INTO WEDNESDAY AND THEN ACROSS THE SOUTHERN GREAT LAKES
REGION WEDNESDAY AFTERNOON INTO THURSDAY. NEW LOW PRESSURE IS
EXPECTED TO DEVELOP OVER THE SOUTHERN PLAINS THURSDAY NIGHT INTO
FRIDAY AND THEN MOVE NORTHEAST ACROSS THE SOUTHERN LAKES THIS
WEEKEND. WHILE WINDS WILL SHIFT TO THE NORTHEAST AS THIS LOW
APPROACHES...THERE STILL REMAINS QUITE A BIT OF UNCERTAINTY
REGARDING THE TRACK...STRENGTHEN AND TIMING OF THIS SYSTEM. CMS
&&
.LOT WATCHES/WARNINGS/ADVISORIES...
IL...NONE.
IN...NONE.
LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS
UNTIL 10 PM TUESDAY.
&&
$$
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1051 AM EST TUE JAN 31 2012
.UPDATE...
MAIN REASON FOR UPDATE WAS TO INCREASE WIND GUSTS TODAY. FREQUENT
GUSTS ALREADY THIS MORNING IN THE 22-27KT RANGE AND EXPECT THAT TO
CONTINUE AS HEATING/MIXING THIS AFTN WEAKENS SFC BASED INVERSION. ALSO
BUMPED TEMPS UP A BIT BASED ON LATEST OBS/LAV GUIDANCE... BUT
STILL EXPECTING HIGHS IN THE M-U50S ACROSS THE CWA THIS AFTN WHICH
IS BLO FWA/SBN RECORDS IN THE L-M60S.
&&
.PREV DISCUSSION... /ISSUED 645 AM EST TUE JAN 31 2012/
AVIATION /12 UTC TAFS/...
MINOR CHNGS WRT 12 UTC TAFS PER LATEST HRRR AND SAT TRENDS. MVFR
SHOULD ADVECT/DEVLP BY ERLY AFTN INTO NCNTL IN PER INCRSG 1000-850MB
MSTR INCRS. BETTER POOLED MSTR ACRS NERN IN COINCIDENT WITH TIMING
OF SHALLOW FNTL FORCING LATER THIS EVE AS SFC FNT APPROACHES...
SUFFCNT ENOUGH SIGNALS TO INTRO TEMPO IFR AT KFWA ONLY ATTM. DRY
ADVECTION POST FNT SHOULD ALLOW CIGS TO RETURN ABOVE FUEL ALT LATE
IN FCST PD.
SHORT TERM...
TODAY THROUGH WEDNESDAY NIGHT. FEW CHNGS REQRD WITH AM ISSUANCE.
PREFERENCE LIES TOWARD NAM/HRRR IN SHORT TERM WITH BETTER LOW LEVEL
RESOLUTION. CWA FIRMLY IN WARM SECTOR TODAY AND WITH SIG WARMER
START AND AT LEAST AM INSOLATION SHOULD AFFORD TEMPS CLOSE TO HIR
NAM GUID/HRRR 2M VALUES...AND IN LINE WITH RESPONSE SEEN YDAY
UPSTREAM. SLIGHT DLAY TO PRECIP ONSET WITH ANTICIPATED SLOWER
FNT/MSTR APPROACH WITH SFC FNTL WAVE CRNTLY ACRS OK/KS. SHALLOW
NATURE OF FNTL CONVERGENCE AXIS AND PREFNTL THETA-E POOL SHOULD
PRECLUDE SIG RAFL AMOUNTS AND CONT WITH HIGH POP/LOW QPF FCST WITH
BEST CHCS ACRS SRN/SERN CWA COINCIDENT WITH TONGUE OF HIR/7-8G/KG
0-0.5KM MIXING RATIOS. SHALLOW NATURE OF FNT/LOW AMPLITUDE POST FNTL
RIDGE OVER CNTL/SRN PLAINS TO PRECLUDE STRONG COOLING INTO WED STILL
WELL ABOVE NORMAL. NEXT UPSTREAM WAVE/WEAK PAC NW ENERGY PER WV
IMAGERY THIS AM TO EJECT EWD THROUGH NRN PLAINS...THOUGH WL MINOR
SUBSTANTIALLY IN RESPONSE TO ARDENT HGHT RISES ACRS EPAC ON DY2
WITH NO SENSIBLE WX ANTICIPATED WED/WED NIGHT.
&&
LONG TERM...
THURSDAY THROUGH MONDAY
MASSIVE WESTERN NOAM RIDGE WITH REX BLOCKING TENDENCIES CONTINUES TO
OFFER MIXED DETERMINISTIC MODEL SOLUTIONS IN THE PERIOD...WITH
DIFFICULTY ARISING IN THE WEEKEND PERIOD. HOWEVER...THE 00Z ECMWF
SEEMS TO BE THE MOST REASONABLE SOLUTION OF ALL PER MID LEVEL FLOW
DURING THE WEEKEND TIME FRAME /GIVEN THE CONSENSUS TREND TOWARD
PROGRESSIVE NORTHERN ATLANTIC FLOW/ OFFERING A NE BIAS TO HEIGHT
FALLS OVER THE NE CONUS. HENCE...THIS WOULD SUGGEST A CONTINUED
SPLIT FLOW PATTERN WITH A RETAINED CUT OFF LOW OVER THE CENTRAL
CONUS. WILL TREND THE FORECAST IN THE DIRECTION...WITH VERY LITTLE
CHANGE MADE TO THE PREVIOUS FORECAST.
AS STATED ABOVE...SPLIT FLOW IS EXPECTED THROUGH MOST OF THE
PERIOD...ESP IF REX BLOCKING /AS INDICATED IN THE 00Z ECMWF/ COMES
TO FRUITION. HAVE RETAINED LOW CHANCES FOR RAIN-SNOW IN THE SAT/SUN
PERIOD DUE TO A WEAK LINGERING CONCERN DOWNSTREAM FLOW DOES BECOME
LESS PROGRESSIVE AS ADVERTISED IN THE GEM AND GFS..SUPPORTING
PARTIAL MID LEVEL TROUGH PHASING. EVEN SO...LIKELY WEAK MID LEVEL
FLOW ASSOCIATED WITH THE SOUTHERN STREAM IMPULSE...WITH AMPLE LL
MOISTURE PER AN OPEN GOMEX WOULD SUPPORT A HEAVY CONVECTIVE
INFLUENCE TO THE REFLECTED LL TROUGH...IMPARTING A SOUTHERN BIAS TO
A THE SFC LOW TRACK AS INDICATED IN THE ECMWF AND GEM. HIGHLY
ANOMALOUS HEIGHT PATTERN FOR JANUARY WILL OFFER MUCH ABOVE NORMAL
TEMPS THROUGH MOST OF THE PERIOD...WITH FAIRLY DRY CONDITIONS...ESP
IF REX TYPE RIDGE SHIFTS EAST INTO THE GREAT LAKES AS DEPICTED IN
THE ECMWF AND TO A LESSER EXTENT THE GEM. RETAINED DRY WEATHER IN
THE SUN NIGHT/MON PERIOD...GIVEN CONCERNS ON BLOCKED UPSTREAM
FLOW...WITH A STRONG NORTHER BIAS TO ANY NORTHERN STREAM IMPULSES.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR LMZ043-046.
&&
$$
SHORT TERM...MURPHY
LONG TERM...JC
AVIATION...MURPHY
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
459 AM EST TUE JAN 31 2012
.SHORT TERM...
TODAY THROUGH WEDNESDAY NIGHT. FEW CHNGS REQRD WITH AM ISSUANCE.
PREFERENCE LIES TOWARD NAM/HRRR IN SHORT TERM WITH BETTER LOW LEVEL
RESOLUTION. CWA FIRMLY IN WARM SECTOR TODAY AND WITH SIG WARMER
START AND AT LEAST AM INSOLATION SHOULD AFFORD TEMPS CLOSE TO HIR
NAM GUID/HRRR 2M VALUES...AND IN LINE WITH RESPONSE SEEN YDAY
UPSTREAM. SLIGHT DLAY TO PRECIP ONSET WITH ANTICIPATED SLOWER
FNT/MSTR APPROACH WITH SFC FNTL WAVE CRNTLY ACRS OK/KS. SHALLOW
NATURE OF FNTL CONVERGENCE AXIS AND PREFNTL THETA-E POOL SHOULD
PRECLUDE SIG RAFL AMOUNTS AND CONT WITH HIGH POP/LOW QPF FCST WITH
BEST CHCS ACRS SRN/SERN CWA COINCIDENT WITH TONGUE OF HIR/7-8G/KG
0-0.5KM MIXING RATIOS. SHALLOW NATURE OF FNT/LOW AMPLITUDE POST FNTL
RIDGE OVER CNTL/SRN PLAINS TO PRECLUDE STRONG COOLING INTO WED STILL
WELL ABOVE NORMAL. NEXT UPSTREAM WAVE/WEAK PAC NW ENERGY PER WV
IMAGERY THIS AM TO EJECT EWD THROUGH NRN PLAINS...THOUGH WL MINOR
SUBSTANTIALLY IN RESPONSE TO ARDENT HGHT RISES ACRS EPAC ON DY2
WITH NO SENSIBLE WX ANTICIPATED WED/WED NIGHT.
.&&
.LONG TERM...
THURSDAY THROUGH MONDAY
MASSIVE WESTERN NOAM RIDGE WITH REX BLOCKING TENDENCIES CONTINUES TO
OFFER MIXED DETERMINISTIC MODEL SOLUTIONS IN THE PERIOD...WITH
DIFFICULTY ARISING IN THE WEEKEND PERIOD. HOWEVER...THE 00Z ECMWF
SEEMS TO BE THE MOST REASONABLE SOLUTION OF ALL PER MID LEVEL FLOW
DURING THE WEEKEND TIME FRAME /GIVEN THE CONSENSUS TREND TOWARD
PROGRESSIVE NORTHERN ATLANTIC FLOW/ OFFERING A NE BIAS TO HEIGHT
FALLS OVER THE NE CONUS. HENCE...THIS WOULD SUGGEST A CONTINUED
SPLIT FLOW PATTERN WITH A RETAINED CUT OFF LOW OVER THE CENTRAL
CONUS. WILL TREND THE FORECAST IN THE DIRECTION...WITH VERY LITTLE
CHANGE MADE TO THE PREVIOUS FORECAST.
AS STATED ABOVE...SPLIT FLOW IS EXPECTED THROUGH MOST OF THE
PERIOD...ESP IF REX BLOCKING /AS INDICATED IN THE 00Z ECMWF/ COMES
TO FRUITION. HAVE RETAINED LOW CHANCES FOR RAIN-SNOW IN THE SAT/SUN
PERIOD DUE TO A WEAK LINGERING CONCERN DOWNSTREAM FLOW DOES BECOME
LESS PROGRESSIVE AS ADVERTISED IN THE GEM AND GFS..SUPPORTING
PARTIAL MID LEVEL TROUGH PHASING. EVEN SO...LIKELY WEAK MID LEVEL
FLOW ASSOCIATED WITH THE SOUTHERN STREAM IMPULSE...WITH AMPLE LL
MOISTURE PER AN OPEN GOMEX WOULD SUPPORT A HEAVY CONVECTIVE
INFLUENCE TO THE REFLECTED LL TROUGH...IMPARTING A SOUTHERN BIAS TO
A THE SFC LOW TRACK AS INDICATED IN THE ECMWF AND GEM. HIGHLY
ANOMALOUS HEIGHT PATTERN FOR JANUARY WILL OFFER MUCH ABOVE NORMAL
TEMPS THROUGH MOST OF THE PERIOD...WITH FAIRLY DRY CONDITIONS...ESP
IF REX TYPE RIDGE SHIFTS EAST INTO THE GREAT LAKES AS DEPICTED IN
THE ECMWF AND TO A LESSER EXTENT THE GEM. RETAINED DRY WEATHER IN
THE SUN NIGHT/MON PERIOD...GIVEN CONCERNS ON BLOCKED UPSTREAM
FLOW...WITH A STRONG NORTHER BIAS TO ANY NORTHERN STREAM IMPULSES.
&&
.AVIATION /06 UTC TAFS/...
SLIGHT INCRS IN 2KFT WINDS WITH SIG SPEED AND APPROX 30 DEGREES
VEERING IN LLVLS TO CONTINUE UNTIL MIDDAY MIXOUT OF STOUT SFC BASED
INVERSION. LOW CONFIDENCE ON WRT DEVELOPMENT OF STRATOCU DECK TIMING
AND HGHT AND AS SUCH HAVE FAVORED MORE OPTIMISTIC LOW END VFR DECK
DVLPG MIDDAY...IN REASONABLE AGREEMENT WITH HRRR OUTPUT/FAVORED MOS
CATEGORIES. MSTR POOLING AHEAD OF FNT TO MOVE EWD THRU NRN IN THIS
EVE/ERLY TNGHT PROMPTING REDUCTION INTO FUEL ALT CONDS COINCIDENT
WITH MOST PROBABLE PD OF RAFL.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR LMZ043-046.
&&
$$
SHORT TERM...MURPHY
LONG TERM...JC
AVIATION...MURPHY
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
103 AM EST TUE JAN 31 2012
.AVIATION /06 UTC TAFS/...
SLIGHT INCRS IN 2KFT WINDS WITH SIG SPEED AND APPROX 30 DEGREES
VEERING IN LLVLS TO CONTINUE UNTIL MIDDAY MIXOUT OF STOUT SFC BASED
INVERSION. LOW CONFIDENCE ON WRT DEVELOPMENT OF STRATOCU DECK TIMING
AND HGHT AND AS SUCH HAVE FAVORED MORE OPTIMISTIC LOW END VFR DECK
DVLPG MIDDAY...IN REASONABLE AGREEMENT WITH HRRR OUTPUT/FAVORED MOS
CATEGEGORIES. MSTR POOLING AHEAD OF FNT TO MOVE EWD THRU NRN IN THIS
EVE/ERLY TNGHT PROMPTING REDUCTION INTO FUEL ALT CONDS COINCIDENT
WITH MOST PROBABLE PD OF RAFL.
&&
.UPDATE...
SOME HIGH CLOUDS TO OVERSPREAD ESPECIALLY SOUTHERN SECTIONS OF THE
FORECAST AREA DURING THE LATE EVENING AND OVERNIGHT HOURS IN
ASSOCIATION WITH A WEAK SHORT WAVE EVIDENT ON WATER VAPOR IMAGERY
THIS EVENING ACROSS NORTHERN MISSOURI. DESPITE PARTLY
CLOUDY/MOSTLY CLEAR SKIES FOR THE OVERNIGHT...DIURNAL SWINGS WILL
BE RATHER MINIMAL AS A TIGHT SFC PRESSURE GRADIENT AND AN
UNSEASONABLY MILD AIR MASS CONTINUE TO AFFECT THE AREA. QUITE A
RANGE OF TEMPERATURE READINGS ACROSS THE AREA AT 01Z WITH THE
WARMEST TEMPS CURRENTLY ACROSS THE NORTHWEST WHERE SFC GRADIENT
REMAINS A BIT STRONGER WITH WIND GUSTS AT KSBN OVER PAST FEW HOURS
STILL UP AROUND 25 TO 30 MPH. JUST MINOR TWEAKS MADE TO HOURLY
TEMPS AND PERHAPS SOME SLIGHT DOWNWARD ADJUSTMENT TO MINS IN SOME
SPOTS BASED ON CURRENT TRENDS. MINS FROM LOWER 40S SOUTHWEST TO
UPPER 30S NORTHEAST STILL APPEAR TO BE REASONABLE GIVEN
ORIENTATION OF LOW LEVEL THERMAL RIDGING. CONTINUED NORTHWARD
PROGRESSION OF THE LOW LEVEL WARM FRONT SHOULD EVENTUALLY ALLOW
GRADIENT TO TIGHTEN IN THE FAR NORTHEAST...AND THUS WILL LIKELY
SEE TEMPS BOTTOM OUT OVER THE NEXT FEW HOURS ACROSS THESE
LOCATIONS BEFORE A STEADY OR SLOWLY RISING TEMP TREND OVERNIGHT.
&&
.PREV DISCUSSION... /ISSUED 301 PM EST MON JAN 30 2012/
SHORT TERM... / TONIGHT THROUGH TUESDAY NIGHT /
WARM FRONT NOW OVER THE CWA WILL LIFT NWD TOWARDS THE NORTHERN GREAT
LAKES TONIGHT INTO TUESDAY...WITH DEEP SOUTHWESTERLY FLOW SUPPORTING
UNSEASONABLY MILD TEMPS THIS PERIOD. MID LVL CLOUD DECK ASSOCIATED
WITH STRONG 50 KT CROSS ISOBARIC FLOW AND REDUCED CPD`S ON THE 295K
SFC WILL EXIT FROM W TO E LATE THIS AFTERNOON WITH JUST SOME PASSING
CIRRUS FOR MUCH OF TONIGHT. THE MAIN FCST CONCERN THIS PACKAGE
CONTINUES TO REVOLVE AROUND STRATUS/FOG/DRIZZLE POTENTIAL LATER
TONIGHT INTO TUESDAY GIVEN 1000-850 HPA THETA-E RISES OVER A MELTING
SNOW PACK...RESULTING IN BOUNDARY LAYER SATURATION AND A
STRENGTHENING LOW LVL INVERSION. THE NAM CONTINUES TO APPEAR TOO
AGGRESSIVE WITH THIS OCCURRING TONIGHT...ESPECIALLY GIVEN THE FACT
THAT UPSTREAM SFC DEWPOINTS ARE RUNNING A LITTLE LOWER THAN PROGGED
BY THIS MODEL. AS A RESULT FAVOR THE SREF AND GFS SOLUTIONS WITH
STRATUS/DRIZZLE NOT REALLY SETTLING IN UNTIL LATE TUESDAY MORNING OR
AFTERNOON...MAINLY WESTERN/NORTHERN AREAS. IF AND HOW FAST THIS
DEVELOPS WILL HAVE A PROFOUND EFFECT ON HIGH TEMPS TOMORROW. TRENDED
TEMPS THROUGH PERIOD WARMER THAN CLIMO BIASED MOS GUIDANCE GIVEN
RECENT MODEL PERFORMANCE IN WAA REGIMES.
SHORTWAVE TROUGH OVER MONTANA THIS AFTERNOON WILL PROPAGATE EWD
INTO THE NORTHERN GREAT LAKES BY LATE TUESDAY/TUESDAY NIGHT...
FORCING A COLD FRONT THROUGH DURING THIS TIME. LOW LVL THETA-E
PLUME ALONG AND AHEAD OF THIS FEATURE SHOULD ALLOW A BAND OF LIGHT
RAIN/DRIZZLE TO DEVELOP AND WORK THROUGH...BEST CHANCES IN THE
SOUTH AND EAST. RAINFALL AMOUNTS SHOULD BE LIGHT AS STRONGER
MID/UPPER LEVEL ASCENT / PER MODEL Q-VECTOR AND PVA CHARTS /
BYPASSES TO THE NORTH WITH MOISTURE LOOKING RELATIVELY SHALLOW.
CONTINUED WITH POPS ABOVE MOS GUIDANCE WITH A LOW QPF/HIGH POP
EVENT ANTICIPATED.
LONG TERM... / WEDNESDAY THROUGH MONDAY /
EXTREME VOLATILITY CONTS THIS PD W/CERTAIN PATTN CHG IN STORE AND
EXEMPLIFIED BY DIZZING ARRAY OF MODEL SOLUTIONS OF NOAM FLW.
FURTHER...12Z MED RANGE GUIDANCE AS A WHOLE LOOKS DEFICIENT IN
DEPTH OF PLAINS HGT FALLS/TROUGH DEPTH LT WEEK ALTHOUGH 12Z GEFS
MEANS REMAIN SUPPORTIVE OF YDAS 12Z ECMWF/GEM LOOK OF DEEPER SRN
PLAINS CYCLOGENESIS AND THAT RATIONAL REMAINS THE FVRD OPTION
GOING FORWARD. THUS THIS YIELDS NO DETERMINISTIC DETAIL OF NOTE TO
WARRANT SIG SPECIFIC CHGS TO PRIOR GRIDS THIS PD. HOPEFULLY
PLANNED NEPAC RECON FLIGHTS WILL LEAD TO SOME MITIGATION OVER THE
COURSE OF THIS WEEK AS OMINOUS SIGNALS REMAIN W/POTENTIAL SIG FLW
PERTURBATIONS OVR THE CNTRL/ERN US LATE WEEK AS WRN RIDGE/ERN
TROUGH PATTN DVLPS. TELECONNECTIONS WOULD FAVOR DVLPMNT OF SIG
SYNOPTIC WAVE OVR THE SRN PLAINS AND SUBSEQUENT NEWD EJECTION UP
THROUGH THE OH VALLEY.
OTHERWISE MORE CERTAIN WRN RIDGE EXPANSION NWD THROUGH WRN
CANADA/ALASKA PORTENDS A LIKELY ARCTIC INVASION INTO THE CNTRL/ERN
US BY LATE NXT WEEK.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 7 PM EST TUESDAY FOR LMZ043-046.
&&
$$
SHORT TERM...STEINWEDEL
LONG TERM...T
AVIATION...MURPHY
UPDATE...MARSILI
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
554 AM CST TUE JAN 31 2012
.AVIATION...
EARLIER AMENDED TAFS TO ADD LLWS AND HAVE MAINTAINED MENTION THROUGH
MID AM WITH KDVN 12Z RAOB SHOWING STRONG WINDS OF 23048KT AT 1900 FT.
STRATUS WITH GENERALLY MVFR CIGS CONTINUES STREAMING NWD ON 40-50 KT
LOW LEVEL JET... AND IS APPROACHING SOUTHEAST IA ATTIM. EXPECT
THE STRATUS TO CONTINUE MOVING NE AND WILL OVERSPREAD KBRL AND KMLI
TERMINALS BY MID AM... AND PERSIST THROUGH THE AFTN. THE STRATUS
IS SHOWN BY LATEST MODELS TO STAY MOSTLY SOUTH OF KCID AND KDBQ
TERMINALS... AS LOW LEVEL FLOW CONTINUES VEERING TO SW AHEAD OF AN
APPROACHING WEAK COLD FRONT... BUT THIS WILL NEED TO BE MONITORED.
PATCHY LIGHT RAIN AND/OR SPRINKLES WILL BE POSSIBLE THIS AFTN THROUGH
SUNSET ALONG AND ESPECIALLY SE OF KBRL-KMLI. CONFIDENCE TOO LOW
FOR INCLUSION IN 12Z TAFS DUE TO WEAKENING LOW LEVEL CONVERGENCE.
ANY PCPN LIKELY TO BE VERY LIGHT AND NOT CAUSE A REDUCTION IN VSBYS.
AFOREMENTIONED WEAK COLD FRONT TO PASS LATE THIS AFTN AND EARLY THIS
EVE WITH CONDITIONS LIKELY BECOMING VFR WITHIN A FEW HRS OF PASSAGE AS
WINDS SHIFT TO W/NW AOB 10 KTS. WINDS LIKELY TO DROP OFF LATE TNGT WITH
SFC RIDGE SETTLING IN... AND MAY SEE SOME FOG DUE TO RADIATIONAL COOLING
WITH VSBYS 2-6SM.
&&
.PREV DISCUSSION... /ISSUED 323 AM CST TUE JAN 31 2012/
SYNOPSIS...
DOUBLE BARREL SFC LOW OVER WESTERN MN WITH WARM FRONT EXTENDING THROUGH
CENTRAL WI AND MI... AND WEAK COLD FRONT EXTENDING SWD AND JUST MOVING
INTO WESTERN IA ATTIM. GUSTY S/SW WINDS PRE-FRONTAL PUMPING IN THE
MILD AIR WITH TEMPS AT 08Z RUNNING 15-20 DEGS ABOVE THOSE OF YSTDY AT
THIS TIME FOR MOST AREAS... WITH TEMPS RANGING FROM THE M/U 30S IN THE
NORTH TO THE L50S PORTIONS OF THE SOUTH. THESE VALUES ARE 10-18 DEGS
ABOVE NORMAL HIGHS FOR TDY! SKIES MOSTLY CLEAR ATTIM WITH JUST SOME
HIGH THIN CIRRUS PASSING ACROSS THE NORTH WITH RIGHT ENTRANCE REGION
OF JET FROM GREAT LAKES TO NEW ENGLAND. LOW LEVEL MOISTURE CONTINUES TO
SURGE NWD THROUGH THE SOUTHERN PLAINS ON 50+ KT LOW LEVEL JET WITH
MUCH OF STRATUS WITHIN AND JUST NORTH OF 50 DEG ISODROSOTHERM WHICH IS
NOSING INTO SOUTHEAST KS ATTIM. ..05..
SHORT TERM...TODAY AND TONIGHT...
CLOUD TRENDS... PCPN CHCS AND HIGH TEMPS MAIN FCST CHALLENGES. MID LEVEL
SHORTWAVE AND ATTENDANT SFC LOW COMPLEX WILL SHIFT INTO THE GREAT
LAKES BY TNGT... AND AS RESULT WILL DRAG WEAK COLD FRONT THROUGH THE
REGION LATE THIS AFTN AND EVE. COMBINATION OF INCREASING LOW LEVEL
MOISTURE AND CONVERGENCE IN 925-850 MB LAYER AHEAD OF FRONT EXPECTED TO
GENERATE LOW CLOUDS THIS AM THROUGH AFTN SOUTHEAST 1/2 TO POSSIBLY 2/3
OF CWA... WITH FEW SPRINKLES OR PATCHY LIGHT RAIN POSSIBLE THIS AFTN
MAINLY S/E OF QUAD CITIES WHERE CONVERGENCE OVERLAPS MOIST AXIS. HIGHS
TDY WILL BE RATHER CHALLENGING AND COMPOUNDED BY POOR MODEL PERFORMANCE
WITH RUC STILL SHOWING 6 INCHES OF SNOW ACROSS THE NORTH... WHILE
NEARLY ALL MODELS OVERDONE WITH NORTHERN EXTENT OF LOW LEVEL RH AT 06Z.
MIXING TO NEAR 925 MB OR A LITTLE DEEPER PER YSTDY WOULD YIELD WIDESPREAD
50S FOR HIGHS TDY. RACE WILL BE EXTENT OF MIXING BEFORE ARRIVAL OF THE
LOW CLOUDS. THOUGHTS ATTIM ARE SOME LOW CLOUDS INTO FAR SOUTH AROUND 12Z
POSSIBLE BUT MOST DVLPMNT BY 15-18Z. WITH TEMPS CURRENTLY IN THE M/U 40S
MOST AREAS EXCEPT FAR NORTH... NOT FAR FROM WARMEST GUIDANCE ALREADY AND
WITH FEW HRS OF SOLAR INSOLATION AND GUSTY SW WINDS HARD NOT SEEING MOST
AREAS GOING ABOVE TO MUCH ABOVE WARMEST GUIDANCE LIKE YSTDY. HI-RES
ECMWF AND GGEM TEMPS VERIFIED BETTER YSTDY AND FOLLOWED MORE CLOSELY TDY
FOR GENERAL RANGE OF L50S TO L60S.
TNGT... SKIES EXPECTED TO GENERALLY BECOMING MOSTLY CLEAR WITH PASSAGE
OF WEAK FRONT AND SFC RIDGE/SUBSIDENCE BUILDING IN. LOWS WIDESPREAD 20S
TO L30S. WILL HAVE TO WATCH N/W SECTIONS WHERE WINDS COULD GO NEAR CALM
FOR SEVERAL HRS LATE AND WITH CLEARING SKIES AND DRIER AIR TEMPS COULD END
UP BEING FEW DEGS COLDER. ..05..
LONG TERM...WEDNESDAY THROUGH NEXT MONDAY...
DRY CONDITIONS WILL BE SEEN WED/WED NIGHT AS ANOTHER FRONT/BOUNDARY
MOVES THROUGH THE AREA. TEMPERATURES WILL CONTINUE TO AVERAGE ABOVE
NORMAL. HIGH PRESSURE WILL MOVE THROUGH THE AREA THURSDAY AND
THURSDAY NIGHT WHICH WILL CONTINUE THE DRY AND WARMER THAN NORMAL
CONDITIONS.
FRIDAY ON...
MODEL CONSENSUS HAS A FAIRLY SUBSTANTIAL MID LATITUDE CYCLONE
AFFECTING THE MIDWEST FRIDAY THROUGH SUNDAY THAT GENERATES SCHC TO
CHC POPS. HOWEVER...THERE ARE PROBLEMS WITH THIS CONSENSUS.
DPROG/DT OF THE MODELS SHOW THE SYSTEM SLOWING DOWN WHICH MAKES
SENSE GIVEN THE SYSTEM IS CUT OFF FROM THE RESPECTIVE STREAMS.
DPROG/DT ALSO SHOWS THE SFC HIGH FROM THE NORTHERN PLAINS INTO THE
UPPER MIDWEST TRENDING STRONGER WHICH DEVELOPS DEEP AND DRY LOW
LEVEL EASTERLY TO NORTHEAST FLOW ACROSS THE AREA. ADDITIONALLY...
THERE IS NOT AS MUCH PHASING OCCURRING WITH THE RESPECTIVE STREAMS.
ALL OF THIS WOULD POINT TO A SLOWER ARRIVAL OF THE SYSTEM AND THE
POTENTIAL FOR MUCH OF THE AREA REMAINING DRY.
UNFORTUNATELY...THERE CONTINUES TO BE VARIABILITY BETWEEN THE MODELS
AND RUN TO RUN CONTINUITY WITH EACH MODEL. THIS VARIABILITY
INDICATES THERE ARE STILL ISSUES ON HOW MUCH PHASING OF THE
RESPECTIVE ENERGIES WILL TAKE PLACE. THE ENERGY THAT IS PROGGED TO
DEVELOP THE CUT OFF SYSTEM IS STILL OVER THE OCEAN SO UNTIL IT COMES
ONSHORE AND GETS SAMPLED BY THE MORE DENSE LAND NETWORKS I EXPECT
THIS VARIABILITY TO CONTINUE.
SUNDAY NIGHT THROUGH MONDAY THE MODEL CONSENSUS HAS DRY CONDITIONS
WITH A COOL DOWN OCCURRING AS A DEEP TROF DEVELOPS OVER THE EASTERN
CONUS. ..08..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
323 AM CST TUE JAN 31 2012
.SYNOPSIS...
DOUBLE BARREL SFC LOW OVER WESTERN MN WITH WARM FRONT EXTENDING THROUGH
CENTRAL WI AND MI... AND WEAK COLD FRONT EXTENDING SWD AND JUST MOVING
INTO WESTERN IA ATTIM. GUSTY S/SW WINDS PRE-FRONTAL PUMPING IN THE
MILD AIR WITH TEMPS AT 08Z RUNNING 15-20 DEGS ABOVE THOSE OF YSTDY AT
THIS TIME FOR MOST AREAS... WITH TEMPS RANGING FROM THE M/U 30S IN THE
NORTH TO THE L50S PORTIONS OF THE SOUTH. THESE VALUES ARE 10-18 DEGS
ABOVE NORMAL HIGHS FOR TDY! SKIES MOSTLY CLEAR ATTIM WITH JUST SOME
HIGH THIN CIRRUS PASSING ACROSS THE NORTH WITH RIGHT ENTRANCE REGION
OF JET FROM GREAT LAKES TO NEW ENGLAND. LOW LEVEL MOISTURE CONTINUES TO
SURGE NWD THROUGH THE SOUTHERN PLAINS ON 50+ KT LOW LEVEL JET WITH
MUCH OF STRATUS WITHIN AND JUST NORTH OF 50 DEG ISODROSOTHERM WHICH IS
NOSING INTO SOUTHEAST KS ATTIM. ..05..
&&
.SHORT TERM...TODAY AND TONIGHT...
CLOUD TRENDS... PCPN CHCS AND HIGH TEMPS MAIN FCST CHALLENGES. MID LEVEL
SHORTWAVE AND ATTENDANT SFC LOW COMPLEX WILL SHIFT INTO THE GREAT
LAKES BY TNGT... AND AS RESULT WILL DRAG WEAK COLD FRONT THROUGH THE
REGION LATE THIS AFTN AND EVE. COMBINATION OF INCREASING LOW LEVEL
MOISTURE AND CONVERGENCE IN 925-850 MB LAYER AHEAD OF FRONT EXPECTED TO
GENERATE LOW CLOUDS THIS AM THROUGH AFTN SOUTHEAST 1/2 TO POSSIBLY 2/3
OF CWA... WITH FEW SPRINKLES OR PATCHY LIGHT RAIN POSSIBLE THIS AFTN
MAINLY S/E OF QUAD CITIES WHERE CONVERGENCE OVERLAPS MOIST AXIS. HIGHS
TDY WILL BE RATHER CHALLENGING AND COMPOUNDED BY POOR MODEL PERFORMANCE
WITH RUC STILL SHOWING 6 INCHES OF SNOW ACROSS THE NORTH... WHILE
NEARLY ALL MODELS OVERDONE WITH NORTHERN EXTENT OF LOW LEVEL RH AT 06Z.
MIXING TO NEAR 925 MB OR A LITTLE DEEPER PER YSTDY WOULD YIELD WIDESPREAD
50S FOR HIGHS TDY. RACE WILL BE EXTENT OF MIXING BEFORE ARRIVAL OF THE
LOW CLOUDS. THOUGHTS ATTIM ARE SOME LOW CLOUDS INTO FAR SOUTH AROUND 12Z
POSSIBLE BUT MOST DVLPMNT BY 15-18Z. WITH TEMPS CURRENTLY IN THE M/U 40S
MOST AREAS EXCEPT FAR NORTH... NOT FAR FROM WARMEST GUIDANCE ALREADY AND
WITH FEW HRS OF SOLAR INSOLATION AND GUSTY SW WINDS HARD NOT SEEING MOST
AREAS GOING ABOVE TO MUCH ABOVE WARMEST GUIDANCE LIKE YSTDY. HI-RES
ECMWF AND GGEM TEMPS VERIFIED BETTER YSTDY AND FOLLOWED MORE CLOSELY TDY
FOR GENERAL RANGE OF L50S TO L60S.
TNGT... SKIES EXPECTED TO GENERALLY BECOMING MOSTLY CLEAR WITH PASSAGE
OF WEAK FRONT AND SFC RIDGE/SUBSIDENCE BUILDING IN. LOWS WIDESPREAD 20S
TO L30S. WILL HAVE TO WATCH N/W SECTIONS WHERE WINDS COULD GO NEAR CALM
FOR SEVERAL HRS LATE AND WITH CLEARING SKIES AND DRIER AIR TEMPS COULD END
UP BEING FEW DEGS COLDER. ..05..
.LONG TERM...WEDNESDAY THROUGH NEXT MONDAY...
DRY CONDITIONS WILL BE SEEN WED/WED NIGHT AS ANOTHER FRONT/BOUNDARY
MOVES THROUGH THE AREA. TEMPERATURES WILL CONTINUE TO AVERAGE ABOVE
NORMAL. HIGH PRESSURE WILL MOVE THROUGH THE AREA THURSDAY AND
THURSDAY NIGHT WHICH WILL CONTINUE THE DRY AND WARMER THAN NORMAL
CONDITIONS.
FRIDAY ON...
MODEL CONSENSUS HAS A FAIRLY SUBSTANTIAL MID LATITUDE CYCLONE
AFFECTING THE MIDWEST FRIDAY THROUGH SUNDAY THAT GENERATES SCHC TO
CHC POPS. HOWEVER...THERE ARE PROBLEMS WITH THIS CONSENSUS.
DPROG/DT OF THE MODELS SHOW THE SYSTEM SLOWING DOWN WHICH MAKES
SENSE GIVEN THE SYSTEM IS CUT OFF FROM THE RESPECTIVE STREAMS.
DPROG/DT ALSO SHOWS THE SFC HIGH FROM THE NORTHERN PLAINS INTO THE
UPPER MIDWEST TRENDING STRONGER WHICH DEVELOPS DEEP AND DRY LOW
LEVEL EASTERLY TO NORTHEAST FLOW ACROSS THE AREA. ADDITIONALLY...
THERE IS NOT AS MUCH PHASING OCCURRING WITH THE RESPECTIVE STREAMS.
ALL OF THIS WOULD POINT TO A SLOWER ARRIVAL OF THE SYSTEM AND THE
POTENTIAL FOR MUCH OF THE AREA REMAINING DRY.
UNFORTUNATELY...THERE CONTINUES TO BE VARIABILITY BETWEEN THE MODELS
AND RUN TO RUN CONTINUITY WITH EACH MODEL. THIS VARIABILITY
INDICATES THERE ARE STILL ISSUES ON HOW MUCH PHASING OF THE
RESPECTIVE ENERGIES WILL TAKE PLACE. THE ENERGY THAT IS PROGGED TO
DEVELOP THE CUT OFF SYSTEM IS STILL OVER THE OCEAN SO UNTIL IT COMES
ONSHORE AND GETS SAMPLED BY THE MORE DENSE LAND NETWORKS I EXPECT
THIS VARIABILITY TO CONTINUE.
SUNDAY NIGHT THROUGH MONDAY THE MODEL CONSENSUS HAS DRY CONDITIONS
WITH A COOL DOWN OCCURRING AS A DEEP TROF DEVELOPS OVER THE EASTERN
CONUS. ..08..
&&
.AVIATION... /ISSUED 1137 PM CST MON JAN 30 2012/
VFR CONDITIONS TO CONTINUE THIS EVENING AND MOST OF OVERNIGHT.
THERE IS SOME STRATUS OVER TEXAS AND OKLAHOMA...WHICH SHOULD
STREAM NORTH ON THE 925-850MB SOUTHWEST FLOW OF 40-50KTS. AT THIS
TIME IT APPEARS THAT THE STRATUS WILL MISS THE TERMINALS TO THE
EAST...BUT IT WILL HAVE TO BE MONITORED FOR TRENDS. SOUTHWEST
WINDS AROUND 10 KTS SHOULD INCREASE TO 10-15KTS DURING THE
MORNING. A COLD FRONT WILL PASS ACROSS THE AREA DURING THE
AFTERNOON HOURS...SWEEPING ALL POTENTIAL FOR STRATUS OFF TO THE
EAST...AND TURNING WINDS TO THE WEST AT 10-15KTS. ..LE..
&&
.DVN WATCHES/WARNINGS/ADVISORIES...
IA...NONE.
IL...NONE.
MO...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TOPEKA KS
1141 PM CST MON JAN 30 2012
...UPDATE TO AVIATION...
.DISCUSSION...
21Z WATER VAPOR IMAGERY SHOWS A SHORTWAVE MOVING ACROSS MT AND ID
AND INTO THE NORTHERN PLAINS. MEANWHILE SURFACE OBS SHOW A BROAD
TROUGH OF LOW PRESSURE FROM THE SOUTHERN HIGH PLAINS INTO THE
NORTHERN PLAINS. THIS HAS ALLOWED FOR HIGHS TO WARM INTO THE MID
AND UPPER 60S WHILE DEWPOINTS INCREASED INTO THE 30S ACROSS THE
FORECAST AREA.
FOR TONIGHT AND TUESDAY...THE MAIN CONCERN IS WHAT THE STRONG
MOISTURE ADVECTION WILL DO OVERNIGHT AND EARLY TUESDAY MORNING.
MODELS ARE KEEPING THE FORCING FROM THE NORTHERN PLAINS SHORTWAVE TO
THE NORTH OF THE FORECAST AREA...AND A DECENT ELEVATED MIXED LAYER
IS PROGGED TO KEEP THE BOUNDARY LAYER CAPPED. THEREFORE CHANCES FOR
MEASURABLE PRECIP LOOK PRETTY SLIM AS A COLD FRONT ASSOCIATED WITH
THE NORTHERN PLAINS WAVE PUSHES THROUGH THE AREA DURING THE DAY
TUESDAY. HOWEVER LOW LEVEL MOISTURE IS EXPECTED TO CONTINUE TO
ADVECT NORTH INTO EASTERN KS THROUGH THE NIGHT WITH READINGS
POSSIBLY IN THE MID 40S BY SUNRISE. THE LATEST RUC AND NAM FORECAST
SOUNDINGS CONTINUE TO SHOW THE BOUNDARY LAYER SATURATING BY 12Z
AHEAD OF THE SFC COLD FRONT. THERE ALSO APPEARS TO BE SOME WEAK LIFT
ON THE 285K ISENTROPIC SFC AHEAD OF THE FRONT. THEREFORE DID NOT SEE
ANY REASON TO CHANGE THE MENTION OF FOG AND DRIZZLE FROM THE
PREVIOUS FORECAST. WINDS SHOULD STAY UP FAVORING MORE STRATUS THAN
FOG SO DO NOT ANTICIPATE THERE BEING A SEVERE RESTRICTION TO
VISIBILITIES AT THIS TIME. OVERNIGHT LOWS WILL BE MILD DUE TO THE
WARM AIR AND MOISTURE MOVING NORTH. FOR HIGHS TUESDAY...THE MODELS
ARE MIXING THE BOUNDARY LAYER TO AT LEAST 900 MB WITH NOT A WHOLE
LOT OF COLD AIR BEHIND THE FRONT. BECAUSE OF THIS...HAVE BUMPED HIGHS
UP INTO THE UPPER 50S AND AROUND 60 THINKING THERE SHOULD BE ENOUGH
INSOLATION IN THE AFTERNOON TO HELP TEMPS WARM.
WOLTERS
FOR TUESDAY NIGHT THROUGH THURSDAY...MID AND HIGH LEVEL CLOUDS COULD
BE RATHER PERSISTENT...WITH A BRIEF BREAK LATE WEDNESDAY...WITH MID
AND LOW LEVELS STILL ON THE DRY SIDE BEHIND THE COLD FRONT. AS
MENTIONED ABOVE...AIRMASS COMING IN BEHIND IS ONLY SLIGHTLY COOLER
THAN TUESDAY...BUT MIXING WILL BE MORE LIMITED FOR WEDNESDAY SO
EXPECT SOMEWHAT COOLER TEMPS. FAVORING THE MORE-AGREED-UPON SLOWER
MODELS OVER THE NAM FOR THURSDAY...WITH WEAK MID LEVEL WARM AIR
ADVECTION BRINGING IN DEEPENING HIGH CLOUDS THURSDAY AFTERNOON AS
THE WESTERN UPPER TROF DIGS INTO THE ROCKIES. TEMPS IN THE LOW TO
MID 50S STILL EXPECTED UNDER EASTERLY WINDS.
MEDIUM RANGE MODELS CONTINUE TO COME TOGETHER WITH THE UPPER TROF AT
LEAST PARTIALLY CUTTING OFF FROM THE FLOW FOR THE LATE WEEK AND
WEEKEND PERIODS. OF COURSE ANY SPECIFICS ARE FAR FROM CERTAIN...BUT
PRECIPITATION FALLING ON MOST LOCATIONS AT LEAST ONCE IN THIS PERIOD
IS BECOMING A GOOD BET. STILL APPEARS TEMPS MAY BE COLD ENOUGH TO
SUPPORT SOME SNOW...BUT AGAIN MUCH TO BE DETERMINED HERE. OVERALL
TEMPS NOT EXPECTED TO STRAY FAR FROM EARLY FEBRUARY NORMALS.
65
&&
.AVIATION...
SOUTHWEST SURFACE WINDS WILL ADVECT MOISTURE NORTHWARD...CAUSING LOW
STRATUS TO DEVELOP AT THE TAF SITES AROUND 9Z AND LASTING THROUGH
MOST OF TUESDAY MORNING. ATTM...I KEPT LOW END MVFR CEILINGS OF
1,000 TO 1,200 FEET. THERE MAY BE SOME PERIODS OF IFR CEILINGS
BETWEEN 11Z AND 15Z. AFTER 17Z TUE...THE STRATUS SHOULD MIX OUT. A
WEAK COLD FRONT WILL MOVE SOUTHEAST ACROSS THE TAF SITES EARLY TUESDAY
AFTERNOON SWITCHING WINDS FROM THE SOUTHWEST AND WEST TO THE
NORTH. WIND SPEEDS WILL BE UNDER 11 KTS TODAY AT THE TAF SITES.
GARGAN
&&
.TOP WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
957 PM EST WED FEB 1 2012
.SYNOPSIS...
LOW PRESSURE, WILL PASS EASTWARD THROUGH CENTRAL WEST VIRGINIA
OVERNIGHT, AND BRING SHOWERS AND PATCHY FOG TO THE WEST VIRGINIA AND
MARYLAND MOUNTAINS. FARTHER NORTH, ACROSS OHIO AND PENNSYLVANIA,
WEAK HIGH PRESSURE WILL MAINTAIN DRY, MILD CONDITIONS INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH THURSDAY/...
PER RECENT HRRR MODEL OUTPUT, CONTINUE TO FORECAST A PERIOD OF
SHOWERS LATE TONIGHT INTO THURSDAY MORNING ACROSS THE WV-MD
MOUNTAIN, WITH THE EASTWARD PASSAGE OF LOW PRESSURE THROUGH THE
CENTRAL APPALACHIAN MOUNTAINS. PER RECENT SURFACE DATA, HAVE ADDED PATCHY
FOG ACROSS THE HIGHER ELEVATIONS. FARTHER NORTH, ACROSS OHIO AND
WESTERN PENNSYLVANIA, EXPECT SOME EXTRA CLOUDS INTO THURSDAY
MORNING.
HIGH PRESSURE WILL FOLLOW WITH INCREASING SUBSIDENCE TO WIPE OUT
MOST HIGH CLOUDS DAYTIME THURSDAY, BUT THERE CAN BE SUFFICIENT STRATOCUMULUS
TO YIELD PARTLY SUNNY CONDITIONS.
PER BLEND OF RECENT GFS AND NAM MOS, ALONG WITH ECMWF MODEL
OUTPUT, EXPECT LOWS TONIGHT TO BE 10-15 DEGREES WARMER THAN NORMAL.
HIGHS THURSDAY WILL BE 5-10 DEGREES WARMER THAN NORMAL.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
HIGH PRESSURE WILL SETTLE IN OVER THE ENTIRE UPPER OHIO VALLEY
THROUGH FRIDAY NIGHT WITH TEMPERATURES REMAINING 5 TO 10 DEGREES
ABOVE NORMAL.
STILL QUITE A BIT OF MODEL DISAGREEMENT ON SPEED AND NORTHERN
EXTENT OF PRECIP FROM STORM MOVING ACROSS THE PLAINS SATURDAY. FOR
NOW CLOUDS AND ONLY LOW CHC POPS SATURDAY, AS THERE WILL BE QUITE A
BIT OF DRY AIR TO OVERCOME AT FIRST USING ANY SOLUTION.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
A LOW PRESSURE SYSTEM PROGGED TO MOVE EASTWARD FROM THE LOWER/MID
MS VALLEY WILL BRING SCATTERED SHOWERS INTO THE REGION LATE SUNDAY
AND MONDAY. TEMPERATURES ARE FORECAST TO REMAIN WELL ABOVE NORMAL
SUNDAY THROUGH TUESDAY.
ECMWF AND HPC GUIDANCE SHOW A COLD FRONT ADVANCING SOUTHEASTWARD
THROUGH THE UPPER OHIO VALLEY TUESDAY NIGHT AND EARLY WEDNESDAY.
THIS SYSTEM WILL BRING WIDELY SCATTERED PRECIPITATION AND A RETURN
TO NEAR NORMAL TEMPERATURES BY WEDNESDAY.
&&
.AVIATION /03Z THURSDAY THROUGH MONDAY/...
WITH EASTBOUND LOW PRESSURE PASSING THROUGH CENTRAL WEST VIRGINIA
OVERNIGHT, UNABLE TO SPREAD ANY SHOWERS ANY FARTHER NORTH THAN
KCKB, EXPECT VFR CONDITIONS TO CONTINUE ACROSS THE UPPER OHIO
VALLEY OVERNIGHT INTO THURSDAY.
OUTLOOK...THURSDAY NIGHT THROUGH MONDAY...
A WEAK SURFACE RIDGE SHOULD PROVIDE GENERALLY VFR WEATHER THURSDAY
NIGHT INTO SATURDAY. A LOW PRESSURE SYSTEM PROGGED TO MOVE EASTWARD
FROM THE LOWER MS VALLEY WILL BRING SCATTERED SHOWERS AND THE
POTENTIAL FOR RESTRICTIONS LATE SUNDAY INTO MONDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
610 PM EST WED FEB 1 2012
.SYNOPSIS...
LOW PRESSURE, WILL PASS EASTWARD THROUGH CENTRAL WEST VIRGINIA
OVERNIGHT, AND BRING SHOWERS TO THE WEST VIRGINIA AND MARYLAND
MOUNTAINS, BUT JUST AN INCREASE IN CLOUDS ACROSS OHIO AND
PENNSYLVANIA. WEAK HIGH PRESSURE WILL FOLLOW WITH DRY, MILD
CONDITIONS INTO THE WEEKEND.
&&
.NEAR TERM /THROUGH THURSDAY/...
RECENT HRRR HAS BEEN CONFIRMING SREF MODEL OUTPUT, IN SHOWING
SHOWERS WILL BE AFFECTING THE WV-MD MOUNTAINS OVERNIGHT. THE
SHOWERS ARE ASSOCIATED WITH A LOW PRESSURE CENTER PASSING EASTWARD
THROUGH CENTRAL WEST VIRGINIA TONIGHT. EXPECT NO MORE THAN A CLOUD
INCREASE FOR OH-PA.
HIGH PRESSURE WILL FOLLOW WITH INCREASING SUBSIDENCE TO WIPE OUT
MOST HIGH CLOUDS DAYTIME THURSDAY, BUT THERE CAN BE SUFFICIENT STRATOCUMULUS
TO YIELD PARTLY SUNNY CONDITIONS.
PER BLEND OF RECENT GFS AND NAM MOS, ALONG WITH ECMWF MODEL
OUTPUT, EXPECT LOWS TONIGHT TO BE 10-15 DEGREES WARMER THAN NORMAL.
HIGHS THURSDAY WILL BE 5-10 DEGREES WARMER THAN NORMAL.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
HIGH PRESSURE WILL SETTLE IN OVER THE ENTIRE UPPER OHIO VALLEY
THROUGH FRIDAY NIGHT WITH TEMPERATURES REMAINING 5 TO 10 DEGREES
ABOVE NORMAL.
STILL QUITE A BIT OF MODEL DISAGREEMENT ON SPEED AND NORTHERN
EXTENT OF PRECIP FROM STORM MOVING ACROSS THE PLAINS SATURDAY. FOR
NOW CLOUDS AND ONLY LOW CHC POPS SATURDAY, AS THERE WILL BE QUITE A
BIT OF DRY AIR TO OVERCOME AT FIRST USING ANY SOLUTION.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
A LOW PRESSURE SYSTEM PROGGED TO MOVE EASTWARD FROM THE LOWER/MID
MS VALLEY WILL BRING SCATTERED SHOWERS INTO THE REGION LATE SUNDAY
AND MONDAY. TEMPERATURES ARE FORECAST TO REMAIN WELL ABOVE NORMAL
SUNDAY THROUGH TUESDAY.
ECMWF AND HPC GUIDANCE SHOW A COLD FRONT ADVANCING SOUTHEASTWARD
THROUGH THE UPPER OHIO VALLEY TUESDAY NIGHT AND EARLY WEDNESDAY.
THIS SYSTEM WILL BRING WIDELY SCATTERED PRECIPITATION AND A RETURN
TO NEAR NORMAL TEMPERATURES BY WEDNESDAY.
&&
.AVIATION /00Z THURSDAY THROUGH MONDAY/...
WITH EASTBOUND LOW PRESSURE PASSING THROUGH CENTRAL WEST VIRGINIA
OVERNIGHT, UNABLE TO SPREAD ANY SHOWERS ANY FARTHER NORTH THAN
KCKB, EXPECT VFR CONDITIONS TO CONTINUE ACROSS THE UPPER OHIO
VALLEY OVERNIGHT INTO THURSDAY.
OUTLOOK...THURSDAY NIGHT THROUGH MONDAY...
A WEAK SURFACE RIDGE SHOULD PROVIDE GENERALLY VFR WEATHER THURSDAY
NIGHT INTO SATURDAY. A LOW PRESSURE SYSTEM PROGGED TO MOVE EASTWARD
FROM THE LOWER MS VALLEY WILL BRING SCATTERED SHOWERS AND THE
POTENTIAL FOR RESTRICTIONS LATE SUNDAY INTO MONDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
542 PM EST TUE JAN 31 2012
.SYNOPSIS...
A COLD FRONT, MOVING SOUTHEASTWARD THROUGH THE UPPER OHIO VALLEY
LATE TONIGHT AND WEDNESDAY, WILL BRING SHOWERS. TEMPERATURES
BEHIND THE FRONT WILL BE COOLER BUT STILL ABOVE NORMAL.
&&
.NEAR TERM /THROUGH WEDNESDAY/...
ONLY CHANGE TO FORECAST WAS TO SPEED UP ARRIVAL OF RAIN SHOWERS
LATER THIS EVENING AS 18Z MODEL RUNS DEVELOP SHOWERS EARLIER ACROSS
OHIO TONIGHT AND RADAR RETURNS SHOW DEVELOPMENT AT THIS HOUR
ALONG THE OHIO RIVER. NO OTHER SIGNIFICANT CHANGES AND PREVIOUS
DISCUSSION FOLLOWS...
RECENT NAM AND SREF MODEL OUTPUT SHOW THE COLD FRONT WILL BE
PRECEDED BY TWO BANDS OF SHOWERS, WHICH WILL MOVE THROUGH THE
UPPER OHIO VALLEY LATE TONIGHT AND WEDNESDAY MORNING. THERE CAN BE
LINGERING SHOWERS ACROSS THE WV- MD-PA MOUNTAINS INTO LATE
AFTERNOON.
BECAUSE OF THE MILD PREFRONTAL SOUTHWEST WINDS, FORECASTED
TEMPERATURES, USING RECENT GFS LAMP AND MOS, TO BE AS MUCH AS 20-25
DEGREES WARMER THAN NORMAL TONIGHT.
WESTERLY JETSTREAM ALOFT WILL MINIMIZE STRENGTH OF POST FRONTAL
COOLING WEDNESDAY. HENCE, AS SUGGESTED BY GFS AND NAM MOS, EXPECT
HIGHS WEDNESDAY AFTERNOON TO STILL BE 15-20 DEGREES WARMER THAN
NORMAL.
&&
.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
RECENT SREF MODEL OUTPUT CONTINUES TO SHOW A WESTERLY JETSTREAM
ALOFT THIS PERIOD, WHICH WILL RESTRICT THE STRENGTH OF ANY COLD
AIR INTRUSION. A WEAK TROUGH PASSING THROUGH THE UPPER OHIO
VALLEY THURSDAY SHOULD ENSURE MOSTLY CLOUDY SKIES THROUGH THE
PERIOD. HOWEVER, EXPECT LITTLE IF ANY PRECIPITATION, EVEN ACROSS
THE WINDWARD MOUNTAIN SLOPES.
HAVE FORECASTED TEMPERATURES TO BE COOLER THAN WEDNESDAY, BUT
STILL CAN BE 10 DEGREES WARMER THAN NORMAL.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
MORE SO THAN THE LAST FEW DAYS...THE DETERMINISTIC MODELS AND
ENSEMBLE MEANS HAVE BEGUN TO SUGGEST VERY SIMILAR SCENARIOS IN
EJECTION OF THE 500HPA LOW THROUGH THE CENTRAL U.S AND TOWARDS THE
REGION. THE MODELS THAT YESTERDAY SUGGESTED A NEARLY STATIONARY
CUTOFF LOW OVER THE EASTERN ROCKIES...HAVE SPED UP TO A CLOSER
GEFS/GFS SOLUTION THAT HAS BE PREVALENT FOR A FEW DAYS. THE SPLIT
FLOW CONTINUES TO MAKE SOME OF THE FORECAST VARIABLES DIFFICULT
HOWEVER...ESPECIALLY IN REGARDS TO TIMING AND LOCATION OF THE
SURFACE LOW AS IT CROSSES THE OHIO VALLEY.
CONTINUED TO FOLLOW CLOSELY TO HPC GUIDANCE, BUT TOOK THE MOST RECENT
RUNS OF THE GEFS...GFS...AND ECMWF INTO ACCOUNT. KEPT CHANCE POPS IN
THE FORECAST SATURDAY THROUGH SUNDAY AS THE LOW CROSSES. USED A
BLEND OF HPC AND TO A GREATER EXTENT MEX GUIDANCE THROUGH TUESDAY.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
VFR CONDITIONS WILL CONTINUE THIS EVE BUT WL BE MARRED BY
INCREASING...AND LOWERING MID LVL CLDINESS AS STRNG...WARM...MOIST
ADVCTN CONTS IN ADVN OF STRNG LOW PRES MOVG ACRS THE NRN LAKES.
-SHRA ACTIVITY WL ALSO BE ON THE INCRS...BUT RESTRICTIONS ARE NOT
ANTICIPATED UNTIL THE LLVLS GET CLOSER TO SATURATION LTR TNGT. MVFR
IS CONFIDENTLY FORECAST IN THE POST MIDNGT PD...AND SHOULD DOMINATE
AREA TAFS UNTIL FRONTAL PASSAGE LTR ON WEDNESDAY MRNG.
ALSO OF CONCERN IS THE INCREASING INDICATIONS OF MORE LLWS AS
PROGGED VIA THE LATEST NAM AND RUC MDL SOUNDINGS. HAVE THUS ADDED
THIS POTENTIAL FOR THE EVE TAF ISSUANCES WITH NR 50 KTS FORECAST
ABOVE THE INVERSION LEVEL...I.E. ARND 2 KFT...AGAIN UNTIL FRONTAL
PASSAGE LTR ON WED MRNG.
OUTLOOK...WEDNESDAY NIGHT THROUGH SATURDAY...
LATEST DETERMINISTIC MDL SOLNS INDICATE THAT LOW PRES MOVING ALNG
FRONTAL BOUNDARY SHOULD PASS SUFFICIENTLY SOUTH OF UPR OH VALLEY
TERMINALS TO PRECLUDE WIDESPREAD RESTRICTIONS ON WED NGT. SFC WND
WL SHIFT TO THE NW IN THE WAKE OF THAT SYS ON THURSDAY WITH COLD
ADVCTN SPAWNING SOME LAKE/UPSLOPE ENHANCED STRATOCUMULUS. VFR
CONDITIONS ARE EXPECTED TO RTN FRIDAY...BUT ANOTHER LOW MAY DEGRADE
CONDTIONS AGAIN FOR THE WEEKEND.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
611 PM EST WED FEB 1 2012
LATEST UPDATE...AVIATION...
.SYNOPSIS...(415 PM EST WED FEB 1 2012)
HIGH PRESSURE WILL PROVIDE TRANQUIL WEATHER INTO FRIDAY WITH
GENERALLY PARTLY CLOUDY SKIES. MILD CONDITIONS WILL CONTINUE WITH
HIGH TEMPERATURES FORECAST TO PUSH TO AROUND 40 BOTH THURSDAY AND
FRIDAY. NORMAL HIGHS FOR THIS TIME OF YEAR AROUND NEAR 30 DEGREES.
A SYSTEM MAY APPROACH THE SOUTHERN GREAT LAKES OVER THE WEEKEND AND
BRUSH THE AREA WITH A CHANCE OF LIGHT SNOW AND LIGHT RAIN. AT THIS
POINT IT APPEARS THE BRUNT OF THE SYSTEM IN THE FORM OF RAINFALL
WILL BE SOUTH OF THE AREA.
&&
.SHORT TERM...(415 PM EST WED FEB 1 2012)
(TONIGHT THROUGH FRIDAY NIGHT)
NOT MUCH IN THE WAY OF CONCERNS THROUGH THE SHORT TERM. MAIN ITEM
WILL BE THE EXTENT OF LOW CLOUDS TONIGHT. DECIDED GIVEN CLIMATOLOGY
TO ROLL WITH LOWER CLOUDS TRYING TO HANG ON. USED A MOSTLY CLOUDY
WORDING THROUGH THE NIGHT FOR NOW. BUFKIT RUC OVERVIEWS SHOW
MOISTURE HANGING ON BETWEEN 2000-3500FT INTO THURSDAY MORNING. THERE
MAY BE SOME EBB AND FLOW TO THE CLOUDS THOUGH AS THERE IS A CLEARING
LINE PRESSING IN FROM THE SOUTHWEST. ENVISION SOME CLEARING THIS
EVENING WITH THE CLOUDS FILLING BACK IN OVERNIGHT.
BEYOND TONIGHT...GENERALLY A PARTLY CLOUDY FORECAST WITH SURFACE
HIGH PRESSURE IN PLACE. COMPLICATING FACTORS THOUGH ARE A SHORTWAVE
DIVING SOUTHEAST ON THURSDAY WHICH MAY INCREASE CLOUD COVER AND
POTENTIALLY SOME LOW CLOUDS FILTERING IN BEHIND THE WAVE THURSDAY
NIGHT AND FRIDAY.
&&
.LONG TERM...(415 PM EST WED FEB 1 2012)
(SATURDAY THROUGH WEDNESDAY)
FORECAST CONCERNS CONTINUE TO BE THE LOW MOVING OUT OF THE SRN
PLAINS OVER THE WEEKEND.
THE GFS REMAINS CONSISTENT IN MOVING THE LOW FROM OKLAHOMA EAST
ACROSS THE OHIO VALLEY. THE NAM IS ON BOARD WITH THIS SOLUTION. THE
ECMWF IS NOW GIVING A NOD TO THE GFS BY DEVELOPING A LOW OVER
KENTUCKY AND THEN SHEARING IT OUT INTO A TROUGH OVER THE
APPALACHIANS. WITH THE ECMWF NOW WEAKENING IT/S LOW OVER IOWA AND
DEVELOPING ONE FARTHER SOUTH...CONFIDENCE IS INCREASING THAT A LOW
WILL MOVE ACROSS THE OHIO VALLEY OVER THE WEEKEND. THIS TRACK
COUPLED WITH FORECAST SOUNDINGS ALSO SUGGESTS THAT ALL THE PCPN WILL
BE SNOW. HOW MUCH PCPN WE SEE IS STILL UP IN THE AIR...SO TO SPEAK.
BOTH THE NAM/GFS SHOW A NICE SLUG OF PCPN BEHIND THE LOW LIKELY
ASSOCIATED WITH DEFORMATION PROCESSES. HIGHEST CHANCES FOR PCPN WILL
BE ALONG/SOUTH OF I-96 SATURDAY AND SUNDAY. MONDAY LOOKS DRY BEFORE
ANOTHER SHORT WAVE MOVING SOUTH ACROSS THE GREAT LAKES BOOSTS PCPN
CHANCES TUESDAY/WEDNESDAY. TEMPS WILL BE MOSTLY ABOVE NORMAL THROUGH
THE PERIOD.
&&
.AVIATION...(611 PM EST WED FEB 1 2012)
MVFR CEILINGS FROM 1800 TO 2500 FEET AGL WILL CONTINUE OVERNIGHT AS
STRATUS DECK HANGS ON. COULD BE SOME IMPROVEMENT TO VFR THURSDAY
MORNING AS CEILING HEIGHTS COME UP. WINDS WILL BE LIGHT AND VARIABLE.
&&
.MARINE...(415 PM EST WED FEB 1 2012)
SURFACE RIDGING WILL BE SITUATED OVER THE GREAT LAKES AREA THE NEXT
36 HOURS OF SO...PROVIDING RELATIVELY TRANQUIL CONDITIONS OUT ON THE
LAKE. WAVES AROUND 1 FOOT ARE EXPECTED INTO FRIDAY WITH WINDS OF 10
KNOTS OR LESS.
&&
.HYDROLOGY...(415 PM EST WED FEB 1 2012)
RAIN IN THE LAST WEEK OR SO...COMBINED WITH SNOWMELT THE LAST COUPLE
OF DAYS HAS LED TO ELEVATED RIVER LEVELS ACROSS THE AREA. THAT
SAID...MOST SITES REMAIN...OR ARE FORECAST TO REMAIN WITHIN BANK.
THE USGS PERCENT OF NORMAL PAGE INDICATES THAT MOST SITES ARE IN
EITHER THE ABOVE NORMAL OR MUCH ABOVE NORMAL CATEGORY. THE KALAMAZOO
RIVER BASIN AND THE UPPER REACHES OF THE GRAND ARE THE HIGHEST. WE
CURRENTLY HAVE RIVER FLOOD ADVISORIES OUT FOR BURLINGTON...VICKSBURG
AND IONIA. THESE SITES ARE NOT PROJECT TO REACH WARNING STATUS. WITH
DRY WEATHER FORECAST THE NEXT COUPLE DAYS...RIVER HEADLINES SHOULD
REMAIN FAIRLY STABLE.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
SYNOPSIS: DUKE
SHORT TERM: DUKE
LONG TERM: 93
AVIATION: OSTUNO
MARINE: DUKE
HYDROLOGY: DUKE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1135 AM EST TUE JAN 31 2012
UPDATED FOR 18Z AVIATION DISCUSSION
.SYNOPSIS...
WV IMAGERY AND RUC ANALYSIS INDICATED MAINLY ZONAL FLOW ACROSS THE
NRN CONUS WITH A SHORTWAVE FROM NW MN INTO CNTRL SD. AT THE SFC...A
LOW PRES WAS LOCATED OVER NW MN WITH A WARM FRONT FROM CNTRL MN INTO
SRN WI. RADAR INDICATED PATCHY RETURNS OVER LAKE SUPERIOR AND WRN
UPPER MI SUPPORTED BY ISENTROPIC LIFT NORTH OF THE WARM FRONT.
HOWEVER...LITTLE IF ANY WAS REACHING THE GROUND AS OBS INDICATED
MAINLY JUST MID CLOUDS WITH NO PCPN.
&&
.SHORT TERM...TODAY AND TONIGHT
TODAY...EXPECT THE BEST CHANCE OF MEASURABLE PCPN TO REMAIN NORTH
OF THE CWA THIS MORNING WHERE THE GREATEST LIFT (285-295K LAYER) AND
DEEPER SATURATION OCCURS. OTHERWISE...A SUBSTANTIAL 925-750 MB DRY
LAYER WILL LIMIT ANY CHANCE OF RAIN/SNOW OVER UPPER MI. THERE MAY
STILL BE ENOUGH LOW LEVEL MOISTURE OVER THE NORTH HALF OF THE CWA FOR
SOME PATCHY -FZDZ...ESPECIALLY WHERE SRLY UPSLOPE FLOW PREVAILS. AS
THE SHORTWAVE MOVES THROUGH THIS AFTERNOON A PERIOD OF 700-500 MB
FGEN MAY PRODUCE ADDITIONAL LIFT BUT IS NOT EXPECTED TO BE STRONG
ENOUGH TO OVERCOME THE DRY LAYER BENEATH THE MID CLOUDS. EXPECT CLOUD
COVER TO BE THICK ENOUGH TO LIMIT MAX READINGS TO THE MID AND UPPER
30S DESPITE 900 MB TEMPS TO AROUND 5C.
TONIGHT...CAA IN THE WAKE OF THE SFC LOW DROPPING 850 MB TEMPS TO
NEAR -7C WITH INCREASING WNW WINDS MAY BE ENOUGH TO SUPPORT SOME
LIGHT LAKE ENHANCED PCPN INTO WRN UPPER MI DURING THE EVENING AND
FOR LOCATIONS EAST OF MARQUETTE OVERNIGHT. SINCE TEMPS IN THE CLOUD
LAYER (DOWN TO -7C TO -10C) WILL ONLY BE MARGINAL FOR ICE
CRYSTALS...-FZDZ POTENTIAL WILL CONTINUE.
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
HIGH PRESSURE WILL DOMINATE MUCH OF THIS PERIOD...WITH ONLY A
SLIGHT CHANCE OF OFF AND ON PRECIPITATION. WEATHER TYPE WILL REMAIN
TRICKY WITH AFTERNOON HIGH TEMPS IN THE 30S...LOWS MAINLY IN THE
20S...AND LOW LEVEL MOISTURE STUCK BELOW A STRONG INVERSION.
DRIZZLE OR FREEZING DRIZZLE WILL AGAIN BE A CONCERN TO START US OFF
ON WEDNESDAY. WHILE THE BULK OF MOISTURE WILL EXIT WITH THE SFC LOW
OVER FAR SE ONTARIO/S QUEBEC BY 12Z WEDNESDAY...A SFC TROUGH WILL
REMAIN THROUGH THE KEWEENAW PENINSULA/ISLE ROYALE AREA. LINGERING
LOW LEVEL MOISTURE UNDER NW FLOW WILL BE A CONCERN. THIS TROUGH WILL
SLOWLY ERODE WEST TO EAST THROUGH 00Z THURSDAY AS A RIDGE SLIDES IN.
ALTHOUGH LOW LEVEL MOISTURE REMAINS WEDNESDAY NIGHT /WITH THE
SHORTWAVE SLIDING ACROSS THE CWA/...IT DID NOT SEEM LIKE ENOUGH TO
WARRANT THE LOW POPS. ADDED FLURRIES INSTEAD...AFTER MIDNIGHT TO THE
KEWEENAW PENINSULA AND EAST OF MUNISING NEAR LAKE SUPERIOR WHEN SFC
WINDS BECOME MORE WNW.
THURSDAY NIGHT THROUGH MONDAY...
FORECAST MODELS DIVERGE SIGNIFICANTLY TOWARD THE END OF THE WORK
WEEK...PARTICULARLY WITH THE HANDLING OF LOW PRESSURE TO OUR SOUTH.
THE RESULT IS LOWER CONFIDENCE IN THE ONGOING FORECAST FROM FRIDAY
THROUGH MONDAY. THE 30/18Z GFS IS BACKED UP BY THE 30/12Z CANADIAN
AND TO A MUCH LESSER EXTENT THE DGEX. THEY SUPPORT THE SFC LOW
ORGANIZING OUT OF THE 4 CORNERS REGION THURSDAY...SLIDING OVER KS
FRIDAY NIGHT...IA SATURDAY NIGHT...AND SOUTHERN WI BY SUNDAY MORNING.
STRONG HIGH PRESSURE OVER S ONTARIO/QUEBEC AND LAKE SUPERIOR WILL
ACT TO KEEP MAINLY DRY AIR IN PLACE OVER OUR REGION THROUGH AT LEAST
SATURDAY.
WITH ALL THE DIFFERENCES BETWEEN THE ECMWF AND THE OVERALL
CONSENSUS...THEY DO MERGE IN ON HAVING THE SFC LOW JUST SE OF THE
CWA BY 00Z MONDAY...WITH THE GFS BEING MORE PROGRESSIVE THEREAFTER
AS THE SOUTHERN LOW NEARLY MERGES WITH THE NORTHERN STREAM LOW OVER
HUDSON BAY.
JUST HOW MUCH COLD AIR FILTERS IN BEHIND THE LOW IS A QUESTION. THE
30/18Z GFS SUGGESTS 850MB TEMPS WARMING TO AROUND -1C 00Z SUNDAY
PRIOR TO ANY PRECIP...WITH -2 TO -6C AIR NEAR THE LOW ITSELF. THE
COOL NNW FLOW BEHIND THE SYSTEM SUNDAY NIGHT INTO MONDAY BEING LESS
THAN IMPRESSIVE WITH -6C ABOUT THE COLDEST AIR AVAILABLE. THE COLDER
AIR /BELOW -12C LOOKS/ TO REMAIN OVER N MANITOBA/ONTARIO THROUGH
MONDAY. RUN TO RUN CONSISTENCY WITH THE GFS IS ALSO A BIT OF AN
ISSUE...AS THE 12Z GFS DID MERGE WITH THE NORTHERN STREAM A BIT
EARLIER RESULTING IN COLDER AIR OF -12C TO -14C BY MONDAY ACROSS THE
NW COUNTIES.
&&
.AVIATION /FOR THE 18Z TAF ISSUANCE/...
CONFIDENCE IS LOW WITH THIS FORECAST AS LOW CLOUDS THAT HAD CLEARED
OUT EARLY THIS MORNING CAME BACK WITH FOG AT KSAW AND KCMX. WITH A
LOW PRESSURE SYSTEM AND WARM FRONT NEAR THE AREA EARLY THIS
AFTERNOON...THIS WILL CONTINUE TO BE A TRICKY FORECAST. WRAPAROUND
SECTION OF THE STORM SHOULD COME INTO THE AREA THIS AFTERNOON AND
SHOULD LEAD TO VFR CONDITIONS GOING BACK TO MVFR AT KIWD AND KCMX.
SLOW IMPROVEMENT SHOULD OCCUR AT KSAW AS THICK FOG STARTS TO SLOWLY
MIX OUT. BY EVENING AS A COLD FRONT MOVES THROUGH...CONDITIONS WILL
IMPROVE TO MVFR AS CIGS RISE WITH DRIER AIR AND DOWNSLOPE WEST WINDS
OCCUR AT KSAW.
&&
.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...
LOW PRESSURE ACROSS NORTHERN MINNESOTA WILL DRIFT OVER EASTERN UPPER
MICHIGAN BY LATE AFTERNOON...BEFORE EXITING TO THE NEW ENGLAND
STATES WEDNESDAY...WITH A FEW GUSTS NEARING 30KTS OVER EASTERN LAKE
SUPERIOR LATE TONIGHT INTO EARLY WEDNESDAY. OTHERWISE...WINDS SHOULD
REMAIN BELOW 30KTS THROUGH SUNDAY. A WEAK LOW WILL SLIDE ACROSS LAKE
SUPERIOR WEDNESDAY NIGHT INTO EARLY THURSDAY...FOLLOWED BY A RIDGE
THAT WILL SLOWLY BUILD OVER THE AREA THROUGH SATURDAY MORNING. LOW
PRESSURE WILL THEN NEAR LAKE SUPERIOR SATURDAY NIGHT INTO SUNDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
SHORT TERM...JLB
LONG TERM...KF
AVIATION...07
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
655 AM EST TUE JAN 31 2012
UPDATED FOR 12Z AVIATION DISCUSSION
.SYNOPSIS...
WV IMAGERY AND RUC ANALYSIS INDICATED MAINLY ZONAL FLOW ACROSS THE
NRN CONUS WITH A SHORTWAVE FROM NW MN INTO CNTRL SD. AT THE SFC...A
LOW PRES WAS LOCATED OVER NW MN WITH A WARM FRONT FROM CNTRL MN INTO
SRN WI. RADAR INDICATED PATCHY RETURNS OVER LAKE SUPERIOR AND WRN
UPPER MI SUPPORTED BY ISENTROPIC LIFT NORTH OF THE WARM FRONT.
HOWEVER...LITTLE IF ANY WAS REACHING THE GROUND AS OBS INDICATED
MAINLY JUST MID CLOUDS WITH NO PCPN.
&&
.SHORT TERM...TODAY AND TONIGHT
TODAY...EXPECT THE BEST CHANCE OF MEASURABLE PCPN TO REMAIN NORTH
OF THE CWA THIS MORNING WHERE THE GREATEST LIFT (285-295K LAYER) AND
DEEPER SATURATION OCCURS. OTHERWISE...A SUBSTANTIAL 925-750 MB DRY
LAYER WILL LIMIT ANY CHANCE OF RAIN/SNOW OVER UPPER MI. THERE MAY
STILL BE ENOUGH LOW LEVEL MOISTURE OVER THE NORTH HALF OF THE CWA FOR
SOME PATCHY -FZDZ...ESPECIALLY WHERE SRLY UPSLOPE FLOW PREVAILS. AS
THE SHORTWAVE MOVES THROUGH THIS AFTERNOON A PERIOD OF 700-500 MB
FGEN MAY PRODUCE ADDITIONAL LIFT BUT IS NOT EXPECTED TO BE STRONG
ENOUGH TO OVERCOME THE DRY LAYER BENEATH THE MID CLOUDS. EXPECT CLOUD
COVER TO BE THICK ENOUGH TO LIMIT MAX READINGS TO THE MID AND UPPER
30S DESPITE 900 MB TEMPS TO AROUND 5C.
TONIGHT...CAA IN THE WAKE OF THE SFC LOW DROPPING 850 MB TEMPS TO
NEAR -7C WITH INCREASING WNW WINDS MAY BE ENOUGH TO SUPPORT SOME
LIGHT LAKE ENHANCED PCPN INTO WRN UPPER MI DURING THE EVENING AND
FOR LOCATIONS EAST OF MARQUETTE OVERNIGHT. SINCE TEMPS IN THE CLOUD
LAYER (DOWN TO -7C TO -10C) WILL ONLY BE MARGINAL FOR ICE
CRYSTALS...-FZDZ POTENTIAL WILL CONTINUE.
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
HIGH PRESSURE WILL DOMINATE MUCH OF THIS PERIOD...WITH ONLY A
SLIGHT CHANCE OF OFF AND ON PRECIPITATION. WEATHER TYPE WILL REMAIN
TRICKY WITH AFTERNOON HIGH TEMPS IN THE 30S...LOWS MAINLY IN THE
20S...AND LOW LEVEL MOISTURE STUCK BELOW A STRONG INVERSION.
DRIZZLE OR FREEZING DRIZZLE WILL AGAIN BE A CONCERN TO START US OFF
ON WEDNESDAY. WHILE THE BULK OF MOISTURE WILL EXIT WITH THE SFC LOW
OVER FAR SE ONTARIO/S QUEBEC BY 12Z WEDNESDAY...A SFC TROUGH WILL
REMAIN THROUGH THE KEWEENAW PENINSULA/ISLE ROYALE AREA. LINGERING
LOW LEVEL MOISTURE UNDER NW FLOW WILL BE A CONCERN. THIS TROUGH WILL
SLOWLY ERODE WEST TO EAST THROUGH 00Z THURSDAY AS A RIDGE SLIDES IN.
ALTHOUGH LOW LEVEL MOISTURE REMAINS WEDNESDAY NIGHT /WITH THE
SHORTWAVE SLIDING ACROSS THE CWA/...IT DID NOT SEEM LIKE ENOUGH TO
WARRANT THE LOW POPS. ADDED FLURRIES INSTEAD...AFTER MIDNIGHT TO THE
KEWEENAW PENINSULA AND EAST OF MUNISING NEAR LAKE SUPERIOR WHEN SFC
WINDS BECOME MORE WNW.
THURSDAY NIGHT THROUGH MONDAY...
FORECAST MODELS DIVERGE SIGNIFICANTLY TOWARD THE END OF THE WORK
WEEK...PARTICULARLY WITH THE HANDLING OF LOW PRESSURE TO OUR SOUTH.
THE RESULT IS LOWER CONFIDENCE IN THE ONGOING FORECAST FROM FRIDAY
THROUGH MONDAY. THE 30/18Z GFS IS BACKED UP BY THE 30/12Z CANADIAN
AND TO A MUCH LESSER EXTENT THE DGEX. THEY SUPPORT THE SFC LOW
ORGANIZING OUT OF THE 4 CORNERS REGION THURSDAY...SLIDING OVER KS
FRIDAY NIGHT...IA SATURDAY NIGHT...AND SOUTHERN WI BY SUNDAY MORNING.
STRONG HIGH PRESSURE OVER S ONTARIO/QUEBEC AND LAKE SUPERIOR WILL
ACT TO KEEP MAINLY DRY AIR IN PLACE OVER OUR REGION THROUGH AT LEAST
SATURDAY.
WITH ALL THE DIFFERENCES BETWEEN THE ECMWF AND THE OVERALL
CONSENSUS...THEY DO MERGE IN ON HAVING THE SFC LOW JUST SE OF THE
CWA BY 00Z MONDAY...WITH THE GFS BEING MORE PROGRESSIVE THEREAFTER
AS THE SOUTHERN LOW NEARLY MERGES WITH THE NORTHERN STREAM LOW OVER
HUDSON BAY.
JUST HOW MUCH COLD AIR FILTERS IN BEHIND THE LOW IS A QUESTION. THE
30/18Z GFS SUGGESTS 850MB TEMPS WARMING TO AROUND -1C 00Z SUNDAY
PRIOR TO ANY PRECIP...WITH -2 TO -6C AIR NEAR THE LOW ITSELF. THE
COOL NNW FLOW BEHIND THE SYSTEM SUNDAY NIGHT INTO MONDAY BEING LESS
THAN IMPRESSIVE WITH -6C ABOUT THE COLDEST AIR AVAILABLE. THE COLDER
AIR /BELOW -12C LOOKS/ TO REMAIN OVER N MANITOBA/ONTARIO THROUGH
MONDAY. RUN TO RUN CONSISTENCY WITH THE GFS IS ALSO A BIT OF AN
ISSUE...AS THE 12Z GFS DID MERGE WITH THE NORTHERN STREAM A BIT
EARLIER RESULTING IN COLDER AIR OF -12C TO -14C BY MONDAY ACROSS THE
NW COUNTIES.
&&
.AVIATION /FOR THE 12Z TAF ISSUANCE/...
ALTHOUGH THE LOW LEVEL MOISTURE/CLOUDS HAVE MOVED OUT EARLY THIS
MORNING...LEAVING MAINLY MID CLOUDS OVER THE AREA...EXPECT MVFR CIGS
MAY REDEVELOP WITH CONTINUED MOIST SRLY FLOW INTO THE AREA. A PAIR
OF COLD FNTS WILL THEN CROSS THE AREA LATER TDAY. THERE WL BE A
RETURN OF MVFR CIGS OVER THE W WITH UPSLOPE WLY FLOW IN THE WAKE OF
THE FROPA...BUT DOWNSLOPING FLOW WL LIKELY CAUSE CIGS TO RISE TO VFR
AT SAW. THE SECOND STRONGER COLD FROPA WL OCCUR IN THE EARLY
EVENVING. CONDITIONS SHOULD DETERIORATE WITH THE INFLUX OF COLDER
AIR BEHIND THIS FNT...WITH MVFR CIGS AT CMX WITH FAVORABLE UPSLOPE
AND GUSTY WNW FLOW.
&&
.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...
LOW PRESSURE ACROSS NORTHERN MINNESOTA WILL DRIFT OVER EASTERN UPPER
MICHIGAN BY LATE AFTERNOON...BEFORE EXITING TO THE NEW ENGLAND
STATES WEDNESDAY...WITH A FEW GUSTS NEARING 30KTS OVER EASTERN LAKE
SUPERIOR LATE TONIGHT INTO EARLY WEDNESDAY. OTHERWISE...WINDS SHOULD
REMAIN BELOW 30KTS THROUGH SUNDAY. A WEAK LOW WILL SLIDE ACROSS LAKE
SUPERIOR WEDNESDAY NIGHT INTO EARLY THURSDAY...FOLLOWED BY A RIDGE
THAT WILL SLOWLY BUILD OVER THE AREA THROUGH SATURDAY MORNING. LOW
PRESSURE WILL THEN NEAR LAKE SUPERIOR SATURDAY NIGHT INTO SUNDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
SHORT TERM...JLB
LONG TERM...KF
AVIATION...KC
MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
520 AM EST TUE JAN 31 2012
.SYNOPSIS...
WV IMAGERY AND RUC ANALYSIS INDICATED MAINLY ZONAL FLOW ACROSS THE
NRN CONUS WITH A SHORTWAVE FROM NW MN INTO CNTRL SD. AT THE SFC...A
LOW PRES WAS LOCATED OVER NW MN WITH A WARM FRONT FROM CNTR MN INTO
SRN WI. RADAR INDICATED PATCHY RETURNS OVER LAKE SUPERIOR AND WRN
UPPER MI SUPPORTED BY ISENTROPIC LIFT NORTH OF THE WARM FRONT.
HOWEVER...LITTLE IF ANY WAS REACHING THE GROUND AS OBS INDICATED
MAINLY JUST MID CLOUDS WITH NO PCPN.
&&
.SHORT TERM...TODAY AND TONIGHT
TODAY...EXPECT THE BEST CHANCE OF MEASURABLE PCPN TO REMAIN NORTH
OF THE CWA THIS MORNING WHERE THE GREATEST LIFT (285-295K LAYER) AND
DEEPER SATURATION OCCURS. OTHERWISE...A SUBSTANTIAL 925-750 MB DRY
LAYER WILL LIMIT ANY CHANCE OF RAIN/SNOW OVER UPPER MI. THERE MAY
STILL BE ENOUGH LOW LEVEL MOISTURE OVER THE NORTH HALF OF THE CWA FOR
SOME PATCHY -FZDZ...ESPECIALLY WHERE SRLY UPSLOPE FLOW PREVAILS. AS
THE SHORTWAVE MOVES THROUGH THIS AFTERNOON A PERIOD OF 700-500 MB
FGEN MAY PRODUCE ADDITIONAL LIFT BUT IS NOT EXPECTED TO BE STRONG
ENOUGH TO OVERCOME THE DRY LAYER BENEATH THE MID CLOUDS. EXPECT CLOUD
COVER TO BE THICK ENOUGH TO LIMIT MAX READINGS TO THE MID AND UPPER
30S DESPITE 900 MB TEMPS TO AROUND 5C.
TONIGHT...CAA IN THE WAKE OF THE SFC LOW DROPPING 850 MB TEMPS TO
NEAR -7C WITH INCREASEING WNW WINDS MAY BE ENOUGH TO SUPPORT SOME
LIGHT LAKE ENHANCED PCPN INTO WRN UPPER MI DURING THE EVENING AND
FOR LOCATIONS EAST OF MARQUETTE OVERNIGHT. SINCE TEMPS IN THE CLOUD
LAYER (DOWN TO -7C TO -10C) WILL ONLY BE MARGINAL FOR ICE
CRYSTALS...-FZDZ POTENTIAL WILL CONTINUE.
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
HIGH PRESSURE WILL DOMINATE MUCH OF THIS PERIOD...WITH ONLY A
SLIGHT CHANCE OF OFF AND ON PRECIPITATION. WEATHER TYPE WILL REMAIN
TRICKY WITH AFTERNOON HIGH TEMPS IN THE 30S...LOWS MAINLY IN THE
20S...AND LOW LEVEL MOISTURE STUCK BELOW A STRONG INVERSION.
DRIZZLE OR FREEZING DRIZZLE WILL AGAIN BE A CONCERN TO START US OFF
ON WEDNESDAY. WHILE THE BULK OF MOISTURE WILL EXIT WITH THE SFC LOW
OVER FAR SE ONTARIO/S QUEBEC BY 12Z WEDNESDAY...A SFC TROUGH WILL
REMAIN THROUGH THE KEWEENAW PENINSULA/ISLE ROYALE AREA. LINGERING
LOW LEVEL MOISTURE UNDER NW FLOW WILL BE A CONCERN. THIS TROUGH WILL
SLOWLY ERODE WEST TO EAST THROUGH 00Z THURSDAY AS A RIDGE SLIDES IN.
ALTHOUGH LOW LEVEL MOISTURE REMAINS WEDNESDAY NIGHT /WITH THE
SHORTWAVE SLIDING ACROSS THE CWA/...IT DID NOT SEEM LIKE ENOUGH TO
WARRANT THE LOW POPS. ADDED FLURRIES INSTEAD...AFTER MIDNIGHT TO THE
KEWEENAW PENINSULA AND EAST OF MUNISING NEAR LAKE SUPERIOR WHEN SFC
WINDS BECOME MORE WNW.
THURSDAY NIGHT THROUGH MONDAY...
FORECAST MODELS DIVERGE SIGNIFICANTLY TOWARD THE END OF THE WORK
WEEK...PARTICULARLY WITH THE HANDLING OF LOW PRESSURE TO OUR SOUTH.
THE RESULT IS LOWER CONFIDENCE IN THE ONGOING FORECAST FROM FRIDAY
THROUGH MONDAY. THE 30/18Z GFS IS BACKED UP BY THE 30/12Z CANADIAN
AND TO A MUCH LESSER EXTENT THE DGEX. THEY SUPPORT THE SFC LOW
ORGANIZING OUT OF THE 4 CORNERS REGION THURSDAY...SLIDING OVER KS
FRIDAY NIGHT...IA SATURDAY NIGHT...AND SOUTHERN WI BY SUNDAY MORNING.
STRONG HIGH PRESSURE OVER S ONTARIO/QUEBEC AND LAKE SUPERIOR WILL
ACT TO KEEP MAINLY DRY AIR IN PLACE OVER OUR REGION THROUGH AT LEAST
SATURDAY.
WITH ALL THE DIFFERENCES BETWEEN THE ECMWF AND THE OVERALL
CONSENSUS...THEY DO MERGE IN ON HAVING THE SFC LOW JUST SE OF THE
CWA BY 00Z MONDAY...WITH THE GFS BEING MORE PROGRESSIVE THEREAFTER
AS THE SOUTHERN LOW NEARLY MERGES WITH THE NORTHERN STREAM LOW OVER
HUDSON BAY.
JUST HOW MUCH COLD AIR FILTERS IN BEHIND THE LOW IS A QUESTION. THE
30/18Z GFS SUGGESTS 850MB TEMPS WARMING TO AROUND -1C 00Z SUNDAY
PRIOR TO ANY PRECIP...WITH -2 TO -6C AIR NEAR THE LOW ITSELF. THE
COOL NNW FLOW BEHIND THE SYSTEM SUNDAY NIGHT INTO MONDAY BEING LESS
THAN IMPRESSIVE WITH -6C ABOUT THE COLDEST AIR AVAILABLE. THE COLDER
AIR /BELOW -12C LOOKS/ TO REMAIN OVER N MANITOBA/ONTARIO THROUGH
MONDAY. RUN TO RUN CONSISTENCY WITH THE GFS IS ALSO A BIT OF AN
ISSUE...AS THE 12Z GFS DID MERGE WITH THE NORTHERN STREAM A BIT
EARLIER RESULTING IN COLDER AIR OF -12C TO -14C BY MONDAY ACROSS THE
NW COUNTIES.
&&
.AVIATION /FOR THE 06Z TAF ISSUANCE/...
AS A DISTURANCE AND ASSOCIATED WARM FNT APRCHS UPR MI EARLY THIS
MRNG...SOME -FZDZ MAY FALL...ESPECIALLY AT CMX WHERE THE AIR ABV
SHALLOW MOIST LYR IS NOT QUITE AS DRY AS AT SAW AND ESPECIALLY IWD.
BUT UPSLOPE S WIND WL BE MORE CONDUCIVE TO MAINTAINING A LO IFR/
MVFR CIG AT SAW THAN AT THE OTHER 2 SITES. EXPECT MORE LO CLDS/ MVFR
CIGS TO ROLL BACK INTO CMX BY DAYBREAK FOLLOWING THE MOISTENING FM
THE LGT PCPN. A PAIR OF COLD FNTS WILL THEN CROSS THE AREA LATER
TDAY. THERE WL BE A RETURN OF MVFR CIGS OVER THE W WITH UPSLOPE WLY
FLOW IN THE WAKE OF THE FROPA...BUT DOWNSLOPING FLOW WL LIKELY CAUSE
CIGS TO RISE TO VFR AT SAW. THE SECOND STRONGER COLD FROPA WL OCCUR
IN THE EARLY EVNG. CONDITIONS SHOULD DETERIORATE WITH THE INFLUX OF
COLDER AIR BEHIND THIS FNT...WITH CIGS FALLING TO IFR AT CMX WITH
FAVORABLE UPSLOPE AND GUSTY WNW FLOW.
&&
.MARINE /FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE/...
LOW PRESSURE ACROSS NORTHERN MINNESOTA WILL DRIFT OVER EASTERN UPPER
MICHIGAN BY LATE AFTERNOON...BEFORE EXITING TO THE NEW ENGLAND
STATES WEDNESDAY...WITH A FEW GUSTS NEARING 30KTS OVER EASTERN LAKE
SUPERIOR LATE TONIGHT INTO EARLY WEDNESDAY. OTHERWISE...WINDS SHOULD
REMAIN BELOW 30KTS THROUGH SUNDAY. A WEAK LOW WILL SLIDE ACROSS LAKE
SUPERIOR WEDNESDAY NIGHT INTO EARLY THURSDAY...FOLLOWED BY A RIDGE
THAT WILL SLOWLY BUILD OVER THE AREA THROUGH SATURDAY MORNING. LOW
PRESSURE WILL THEN NEAR LAKE SUPERIOR SATURDAY NIGHT INTO SUNDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SYNOPSIS...JLB
SHORT TERM...JLB
LONG TERM...KF
AVIATION...KC
MARINE...KF
AREA FORECAST DISCUSSION
NWS DULUTH MN
1137 AM CST TUE JAN 31 2012
.AVIATION...18Z TAFS
A COLD FRONT WILL PASS THROUGH FAR EASTERN MINNESOTA THIS
AFTERNOON...AND CONTINUE EAST THROUGH WISCONSIN. WINDS WILL REMAIN
OR SWITCH TO THE WEST/NORTHWEST AND IFR OR LOW MVFR CEILINGS WILL
CONTINUE TO SPREAD TO THE EAST WITH THE CAA. THERE MAY BE A BRIEF
PERIOD OF RAIN OR SNOW AS THE FRONT MOVES THROUGH. TONIGHT...LOW
MVFR OR IFR CEILINGS WILL CONTINUE ALONG WITH SOME FOG WITH VSBYS 3
TO 5SM. THE LOWER CEILINGS WILL GRADUALLY LIFT ON ACROSS THE
SOUTHERN HALF OF THE NORTHLAND WEDNESDAY AS WINDS BACK TO MORE
S/SW.
&&
.PREV DISCUSSION... /ISSUED 1032 AM CST TUE JAN 31 2012/
UPDATE...
THE MAIN AREA OF FREEZING RAIN AND/OR SLEET HAS MOVED OFF TO THE
EAST THIS MORNING...AND SKIES HAVE CLEARED OFF MORE THAN
ANTICIPATED OVER MUCH OF THE NORTHLAND. SO...DECIDED TO CANCEL THE
WINTER WEATHER ADVISORY. THERE IS A CHANCE OF SOME LIGHT SNOW
ACCUMULATION ACROSS THE NORTH...WITH A RAIN SNOW MIX POSSIBLE
AROUND THE TWIN PORTS AREA. ONLY A LIGHT SLUSHY MIX WILL BE
POSSIBLE. THE COLD FRONT WILL LIKELY SLIDE BY TO THE
NORTH...SPARING DULUTH OF ANY SIGNIFICANT PRECIP.
PREV DISCUSSION... /ISSUED 417 AM CST TUE JAN 31 2012/
SHORT TERM...
A LOW PRESSURE SYSTEM OVER NORTH CENTRAL MINNESOTA WILL MOVE EASTWARD
TODAY AND CONTINUE TO BRING FREEZING RAIN OVER THE IRON RANGE AND
ARROWHEAD THIS MORNING. CONTINUED THE WINTER WEATHER ADVISORY FOR
AREAS BASICALLY NORTH OF HIGHWAY 2 IN MINNESOTA THROUGH NOON. A
PUSH OF DRIER AIR TO THE SOUTHWEST OF THE LOW HAS PARTIALLY
CLEARED THE SKIES ACROSS WEST CENTRAL MINNESOTA. THE PATCHY
FREEZING RAIN SOUTH OF HIGHWAY 2 HAS MOVED EAST OF THE FORECAST
AREA AND DIMINISHED AND THEREFORE DROPPED THE WINTER WEATHER
ADVISORY FOR THOSE LOCATIONS. A COLD FRONTAL BOUNDARY DRAPED OVER
EXTREME NORTHWESTERN MINNESOTA AND EASTERN NORTH DAKOTA IS THE
FOCUS OF THE NEXT ROUND OF PRECIPITATION. PER SURFACE
OBSERVATIONS...MOST OF THE PRECIPITATION IS FALLING AS FREEZING
RAIN. 4 KM WRF AND HRRR HAVE THIS BAND OF PRECIPITATION
DISSIPATING AS IT MOVES EASTWARD. TEMPERATURES WILL BE WARM
ENOUGH BY 18Z THAT WILL BRING THE PRECIPITATION TO MAINLY A
LIQUID STATE IF IT HOLDS TOGETHER. AS THE FRONTAL BOUNDARY MOVES
INTO NORTHWESTERN WISCONSIN...SOME PATCHY FREEZING DRIZZLE IS
POSSIBLE ALONG THE SOUTH SHORE OF LAKE SUPERIOR...EAST OF
SUPERIOR...IN THE EARLY EVENING WITH THE LOSS OF DIURNAL WARMING.
THERE STILL WILL BE A CHANCE OF PRECIPITATION ON THE BACK SIDE OF
THE LOW EARLY TONIGHT IN THE FORM OF LIGHT SNOW ALONG THE
BORDERLAND. TEMPERATURES BEHIND THE FRONT WILL BE MODIFIED BY
PACIFIC AIR ALLOWING FOR THE 30S TO CONTINUE INTO WEDNESDAY. A
WEAK SHORTWAVE WILL MOVE OUT OF CANADA WEDNESDAY AFTERNOON THAT
WILL BRING A SLIGHT CHANCE OF LIGHT SNOW TO THE NORTHWESTERN PART
OF THE FORECAST AREA.
EXTENDED...WEDNESDAY NIGHT THROUGH TUESDAY.
A WAVY ZONAL FLOW KEEPS CLOUDS AND A FEW PERIODS OF SCHC POPS FOR
-SN IN THE FCST THROUGH THE REMAINDER OF THE WEEK. A LONG WAVE
TROUGH DEEPENS INTO A CLOSED LOW OVER THE SRN/CENTRAL PLAINS THROUGH THE
WEEKEND. LATEST GFS/ECM/GEM HAVE SIMILAR SOLUTIONS SUGGESTING THE
BUILDING RIDGE BEHIND THE LOW BECOMES PINCHED OFF OVER THE NRN
PLAINS/SRN CANADA DURING THIS TIME. THIS WOULD BRING QUITE WEATHER
AND ANOTHER STRETCH OF WELL ABOVE NORMAL TEMPS WITH DAYTIME HIGHS IN
THE 30S FOR THE DLH CWA. MODELS CONTINUE TO SHOW DIFFERENCES IN HOW
FAR NORTH THE CUT OFF LOW MIGRATES INTO THE BEGINNING OF NEXT WEEK
WITH THE GFS THE MOST PROGRESSIVE AND FURTHEST NORTH WITH THE LOW
LIFTING OVER THE SRN GREAT LAKES BY SUNDAY. ATTM...THE PRECIP
ASSOCIATED WITH THE SRN STREAM LOW LOOKS TO REMAIN SOUTH OF THE
FA.
&&
.POINT TEMPS/POPS...
DLH 35 20 34 22 / 20 10 10 10
INL 31 18 34 20 / 50 10 20 10
BRD 36 22 39 20 / 10 10 10 0
HYR 39 22 35 21 / 10 10 10 0
ASX 37 23 36 23 / 10 20 10 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...TENTINGER
LONG TERM....GRANING
AVIATION...MELDE
AREA FORECAST DISCUSSION...UPDATED
NWS DULUTH MN
1032 AM CST TUE JAN 31 2012
.UPDATE...
THE MAIN AREA OF FREEZING RAIN AND/OR SLEET HAS MOVED OFF TO THE
EAST THIS MORNING...AND SKIES HAVE CLEARED OFF MORE THAN
ANTICIPATED OVER MUCH OF THE NORTHLAND. SO...DECIDED TO CANCEL THE
WINTER WEATHER ADVISORY. THERE IS A CHANCE OF SOME LIGHT SNOW
ACCUMULATION ACROSS THE NORTH...WITH A RAIN SNOW MIX POSSIBLE
AROUND THE TWIN PORTS AREA. ONLY A LIGHT SLUSHY MIX WILL BE
POSSIBLE. THE COLD FRONT WILL LIKELY SLIDE BY TO THE
NORTH...SPARING DULUTH OF ANY SIGNIFICANT PRECIP.
&&
.PREV DISCUSSION... /ISSUED 606 AM CST TUE JAN 31 2012/
AVIATION...
A LOW PRESSURE SYSTEM WILL TRACK EAST OVER THE REGION THROUGH THE
AFTERNOON. VFR CIGS THIS MORNING WILL LOWER TO MVFR WITH -DZ OR
-RASN WITH THE COLD FRONT/LOW PASSAGE. AS THE LOW DEPARTS TO OVER THE
GREAT LAKES OVERNIGHT...WRAP AROUND MOISTURE AND COOLER AIR WILL
BRING LOWERING CEILINGS AND A POSSIBILITY FOR REDUCED VSBYS AND
BR. THE DRIER AIR ALOFT MAY RESULT IN SOME FZDZ LATE TONIGHT.
HOWEVER...HAVE LEFT ANY MENTION OF FZDZ OUT OF TAFS AT THIS TIME
DUE TO UNCERTAINTIES THAT FAR OUT.
PREV DISCUSSION... /ISSUED 417 AM CST TUE JAN 31 2012/
SHORT TERM...
A LOW PRESSURE SYSTEM OVER NORTH CENTRAL MINNESOTA WILL MOVE EASTWARD
TODAY AND CONTINUE TO BRING FREEZING RAIN OVER THE IRON RANGE AND
ARROWHEAD THIS MORNING. CONTINUED THE WINTER WEATHER ADVISORY FOR
AREAS BASICALLY NORTH OF HIGHWAY 2 IN MINNESOTA THROUGH NOON. A
PUSH OF DRIER AIR TO THE SOUTHWEST OF THE LOW HAS PARTIALLY
CLEARED THE SKIES ACROSS WEST CENTRAL MINNESOTA. THE PATCHY
FREEZING RAIN SOUTH OF HIGHWAY 2 HAS MOVED EAST OF THE FORECAST
AREA AND DIMINISHED AND THEREFORE DROPPED THE WINTER WEATHER
ADVISORY FOR THOSE LOCATIONS. A COLD FRONTAL BOUNDARY DRAPED OVER
EXTREME NORTHWESTERN MINNESOTA AND EASTERN NORTH DAKOTA IS THE
FOCUS OF THE NEXT ROUND OF PRECIPITATION. PER SURFACE
OBSERVATIONS...MOST OF THE PRECIPITATION IS FALLING AS FREEZING
RAIN. 4 KM WRF AND HRRR HAVE THIS BAND OF PRECIPITATION
DISSIPATING AS IT MOVES EASTWARD. TEMPERATURES WILL BE WARM
ENOUGH BY 18Z THAT WILL BRING THE PRECIPITATION TO MAINLY A
LIQUID STATE IF IT HOLDS TOGETHER. AS THE FRONTAL BOUNDARY MOVES
INTO NORTHWESTERN WISCONSIN...SOME PATCHY FREEZING DRIZZLE IS
POSSIBLE ALONG THE SOUTH SHORE OF LAKE SUPERIOR...EAST OF
SUPERIOR...IN THE EARLY EVENING WITH THE LOSS OF DIURNAL WARMING.
THERE STILL WILL BE A CHANCE OF PRECIPITATION ON THE BACK SIDE OF
THE LOW EARLY TONIGHT IN THE FORM OF LIGHT SNOW ALONG THE
BORDERLAND. TEMPERATURES BEHIND THE FRONT WILL BE MODIFIED BY
PACIFIC AIR ALLOWING FOR THE 30S TO CONTINUE INTO WEDNESDAY. A
WEAK SHORTWAVE WILL MOVE OUT OF CANADA WEDNESDAY AFTERNOON THAT
WILL BRING A SLIGHT CHANCE OF LIGHT SNOW TO THE NORTHWESTERN PART
OF THE FORECAST AREA.
EXTENDED...WEDNESDAY NIGHT THROUGH TUESDAY.
A WAVY ZONAL FLOW KEEPS CLOUDS AND A FEW PERIODS OF SCHC POPS FOR
-SN IN THE FCST THROUGH THE REMAINDER OF THE WEEK. A LONG WAVE
TROUGH DEEPENS INTO A CLOSED LOW OVER THE SRN/CENTRAL PLAINS THROUGH THE
WEEKEND. LATEST GFS/ECM/GEM HAVE SIMILAR SOLUTIONS SUGGESTING THE
BUILDING RIDGE BEHIND THE LOW BECOMES PINCHED OFF OVER THE NRN
PLAINS/SRN CANADA DURING THIS TIME. THIS WOULD BRING QUITE WEATHER
AND ANOTHER STRETCH OF WELL ABOVE NORMAL TEMPS WITH DAYTIME HIGHS IN
THE 30S FOR THE DLH CWA. MODELS CONTINUE TO SHOW DIFFERENCES IN HOW
FAR NORTH THE CUT OFF LOW MIGRATES INTO THE BEGINNING OF NEXT WEEK
WITH THE GFS THE MOST PROGRESSIVE AND FURTHEST NORTH WITH THE LOW
LIFTING OVER THE SRN GREAT LAKES BY SUNDAY. ATTM...THE PRECIP
ASSOCIATED WITH THE SRN STREAM LOW LOOKS TO REMAIN SOUTH OF THE
FA.
AVIATION...01/31/06Z ISSUANCE...
VFR WITH AREAS OF HIGH-END MVFR IN CLOUDS AND FREEZING DRIZZLE OR
FREEZING RAIN. FREEZING RAIN MAY MIX WITH LIGHT SNOW FROM
LONG VILLE-DULUTH ON NORTH TUESDAY MORNING. LOW-END VFR WITH A
LITTLE HIGH-END MVFR IN CLOUDS WILL PERSIST TUESDAY AFTERNOON AND
EVENING.
&&
.POINT TEMPS/POPS...
DLH 35 20 34 22 / 20 10 10 10
INL 31 18 34 20 / 50 10 20 10
BRD 36 22 39 20 / 10 10 10 0
HYR 39 22 35 21 / 10 10 10 0
ASX 37 23 36 23 / 10 20 10 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...NONE.
WI...NONE.
&&
$$
SHORT TERM...TENTINGER
AREA FORECAST DISCUSSION
NWS DULUTH MN
606 AM CST TUE JAN 31 2012
.AVIATION...
A LOW PRESSURE SYSTEM WILL TRACK EAST OVER THE REGION THROUGH THE
AFTERNOON. VFR CIGS THIS MORNING WILL LOWER TO MVFR WITH -DZ OR
-RASN WITH THE COLD FRONT/LOW PASSAGE. AS THE LOW DEPARTS TO OVER THE
GREAT LAKES OVERNIGHT...WRAP AROUND MOISTURE AND COOLER AIR WILL
BRING LOWERING CEILINGS AND A POSSIBILITY FOR REDUCED VSBYS AND
BR. THE DRIER AIR ALOFT MAY RESULT IN SOME FZDZ LATE TONIGHT.
HOWEVER...HAVE LEFT ANY MENTION OF FZDZ OUT OF TAFS AT THIS TIME
DUE TO UNCERTAINTIES THAT FAR OUT.
&&
.PREV DISCUSSION... /ISSUED 417 AM CST TUE JAN 31 2012/
SHORT TERM...
A LOW PRESSURE SYSTEM OVER NORTH CENTRAL MINNESOTA WILL MOVE EASTWARD
TODAY AND CONTINUE TO BRING FREEZING RAIN OVER THE IRON RANGE AND
ARROWHEAD THIS MORNING. CONTINUED THE WINTER WEATHER ADVISORY FOR
AREAS BASICALLY NORTH OF HIGHWAY 2 IN MINNESOTA THROUGH NOON. A
PUSH OF DRIER AIR TO THE SOUTHWEST OF THE LOW HAS PARTIALLY
CLEARED THE SKIES ACROSS WEST CENTRAL MINNESOTA. THE PATCHY
FREEZING RAIN SOUTH OF HIGHWAY 2 HAS MOVED EAST OF THE FORECAST
AREA AND DIMINISHED AND THEREFORE DROPPED THE WINTER WEATHER
ADVISORY FOR THOSE LOCATIONS. A COLD FRONTAL BOUNDARY DRAPED OVER
EXTREME NORTHWESTERN MINNESOTA AND EASTERN NORTH DAKOTA IS THE
FOCUS OF THE NEXT ROUND OF PRECIPITATION. PER SURFACE
OBSERVATIONS...MOST OF THE PRECIPITATION IS FALLING AS FREEZING
RAIN. 4 KM WRF AND HRRR HAVE THIS BAND OF PRECIPITATION
DISSIPATING AS IT MOVES EASTWARD. TEMPERATURES WILL BE WARM
ENOUGH BY 18Z THAT WILL BRING THE PRECIPITATION TO MAINLY A
LIQUID STATE IF IT HOLDS TOGETHER. AS THE FRONTAL BOUNDARY MOVES
INTO NORTHWESTERN WISCONSIN...SOME PATCHY FREEZING DRIZZLE IS
POSSIBLE ALONG THE SOUTH SHORE OF LAKE SUPERIOR...EAST OF
SUPERIOR...IN THE EARLY EVENING WITH THE LOSS OF DIURNAL WARMING.
THERE STILL WILL BE A CHANCE OF PRECIPITATION ON THE BACK SIDE OF
THE LOW EARLY TONIGHT IN THE FORM OF LIGHT SNOW ALONG THE
BORDERLAND. TEMPERATURES BEHIND THE FRONT WILL BE MODIFIED BY
PACIFIC AIR ALLOWING FOR THE 30S TO CONTINUE INTO WEDNESDAY. A
WEAK SHORTWAVE WILL MOVE OUT OF CANADA WEDNESDAY AFTERNOON THAT
WILL BRING A SLIGHT CHANCE OF LIGHT SNOW TO THE NORTHWESTERN PART
OF THE FORECAST AREA.
EXTENDED...WEDNESDAY NIGHT THROUGH TUESDAY.
A WAVY ZONAL FLOW KEEPS CLOUDS AND A FEW PERIODS OF SCHC POPS FOR
-SN IN THE FCST THROUGH THE REMAINDER OF THE WEEK. A LONG WAVE
TROUGH DEEPENS INTO A CLOSED LOW OVER THE SRN/CENTRAL PLAINS THROUGH THE
WEEKEND. LATEST GFS/ECM/GEM HAVE SIMILAR SOLUTIONS SUGGESTING THE
BUILDING RIDGE BEHIND THE LOW BECOMES PINCHED OFF OVER THE NRN
PLAINS/SRN CANADA DURING THIS TIME. THIS WOULD BRING QUITE WEATHER
AND ANOTHER STRETCH OF WELL ABOVE NORMAL TEMPS WITH DAYTIME HIGHS IN
THE 30S FOR THE DLH CWA. MODELS CONTINUE TO SHOW DIFFERENCES IN HOW
FAR NORTH THE CUT OFF LOW MIGRATES INTO THE BEGINNING OF NEXT WEEK
WITH THE GFS THE MOST PROGRESSIVE AND FURTHEST NORTH WITH THE LOW
LIFTING OVER THE SRN GREAT LAKES BY SUNDAY. ATTM...THE PRECIP
ASSOCIATED WITH THE SRN STREAM LOW LOOKS TO REMAIN SOUTH OF THE
FA.
AVIATION...01/31/06Z ISSUANCE...
VFR WITH AREAS OF HIGH-END MVFR IN CLOUDS AND FREEZING DRIZZLE OR
FREEZING RAIN. FREEZING RAIN MAY MIX WITH LIGHT SNOW FROM
LONG VILLE-DULUTH ON NORTH TUESDAY MORNING. LOW-END VFR WITH A
LITTLE HIGH-END MVFR IN CLOUDS WILL PERSIST TUESDAY AFTERNOON AND
EVENING.
&&
.POINT TEMPS/POPS...
DLH 36 22 34 22 / 20 10 10 10
INL 32 21 34 20 / 50 20 20 10
BRD 36 24 38 20 / 10 10 10 0
HYR 39 24 36 21 / 10 10 10 0
ASX 38 25 36 23 / 20 20 10 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR MNZ010>012-
018>021-026.
WI...NONE.
&&
$$
SHORT TERM...KK
LONG TERM....GRANING
AVIATION...GRANING
AREA FORECAST DISCUSSION
NWS DULUTH MN
417 AM CST TUE JAN 31 2012
.SHORT TERM...
A LOW PRESSURE SYSTEM OVER NORTH CENTRAL MINNESOTA WILL MOVE EASTWARD
TODAY AND CONTINUE TO BRING FREEZING RAIN OVER THE IRON RANGE AND
ARROWHEAD THIS MORNING. CONTINUED THE WINTER WEATHER ADVISORY FOR
AREAS BASICALLY NORTH OF HIGHWAY 2 IN MINNESOTA THROUGH NOON. A
PUSH OF DRIER AIR TO THE SOUTHWEST OF THE LOW HAS PARTIALLY
CLEARED THE SKIES ACROSS WEST CENTRAL MINNESOTA. THE PATCHY
FREEZING RAIN SOUTH OF HIGHWAY 2 HAS MOVED EAST OF THE FORECAST
AREA AND DIMINISHED AND THEREFORE DROPPED THE WINTER WEATHER
ADVISORY FOR THOSE LOCATIONS. A COLD FRONTAL BOUNDARY DRAPED OVER
EXTREME NORTHWESTERN MINNESOTA AND EASTERN NORTH DAKOTA IS THE
FOCUS OF THE NEXT ROUND OF PRECIPITATION. PER SURFACE
OBSERVATIONS...MOST OF THE PRECIPITATION IS FALLING AS FREEZING
RAIN. 4 KM WRF AND HRRR HAVE THIS BAND OF PRECIPITATION
DISSIPATING AS IT MOVES EASTWARD. TEMPERATURES WILL BE WARM
ENOUGH BY 18Z THAT WILL BRING THE PRECIPITATION TO MAINLY A
LIQUID STATE IF IT HOLDS TOGETHER. AS THE FRONTAL BOUNDARY MOVES
INTO NORTHWESTERN WISCONSIN...SOME PATCHY FREEZING DRIZZLE IS
POSSIBLE ALONG THE SOUTH SHORE OF LAKE SUPERIOR...EAST OF
SUPERIOR...IN THE EARLY EVENING WITH THE LOSS OF DIURNAL WARMING.
THERE STILL WILL BE A CHANCE OF PRECIPITATION ON THE BACK SIDE OF
THE LOW EARLY TONIGHT IN THE FORM OF LIGHT SNOW ALONG THE
BORDERLAND. TEMPERATURES BEHIND THE FRONT WILL BE MODIFIED BY
PACIFIC AIR ALLOWING FOR THE 30S TO CONTINUE INTO WEDNESDAY. A
WEAK SHORTWAVE WILL MOVE OUT OF CANADA WEDNESDAY AFTERNOON THAT
WILL BRING A SLIGHT CHANCE OF LIGHT SNOW TO THE NORTHWESTERN PART
OF THE FORECAST AREA.
EXTENDED...WEDNESDAY NIGHT THROUGH TUESDAY.
A WAVY ZONAL FLOW KEEPS CLOUDS AND A FEW PERIODS OF SCHC POPS FOR
-SN IN THE FCST THROUGH THE REMAINDER OF THE WEEK. A LONG WAVE
TROUGH DEEPENS INTO A CLOSED LOW OVER THE SRN/CENTRAL PLAINS THROUGH THE
WEEKEND. LATEST GFS/ECM/GEM HAVE SIMILAR SOLUTIONS SUGGESTING THE
BUILDING RIDGE BEHIND THE LOW BECOMES PINCHED OFF OVER THE NRN
PLAINS/SRN CANADA DURING THIS TIME. THIS WOULD BRING QUITE WEATHER
AND ANOTHER STRETCH OF WELL ABOVE NORMAL TEMPS WITH DAYTIME HIGHS IN
THE 30S FOR THE DLH CWA. MODELS CONTINUE TO SHOW DIFFERENCES IN HOW
FAR NORTH THE CUT OFF LOW MIGRATES INTO THE BEGINNING OF NEXT WEEK
WITH THE GFS THE MOST PROGRESSIVE AND FURTHEST NORTH WITH THE LOW
LIFTING OVER THE SRN GREAT LAKES BY SUNDAY. ATTM...THE PRECIP
ASSOCIATED WITH THE SRN STREAM LOW LOOKS TO REMAIN SOUTH OF THE
FA.
&&
.AVIATION...01/31/06Z ISSUANCE...
VFR WITH AREAS OF HIGH-END MVFR IN CLOUDS AND FREEZING DRIZZLE OR
FREEZING RAIN. FREEZING RAIN MAY MIX WITH LIGHT SNOW FROM
LONGVILLE-DULUTH ON NORTH TUESDAY MORNING. LOW-END VFR WITH A
LITTLE HIGH-END MVFR IN CLOUDS WILL PERSIST TUESDAY AFTERNOON AND
EVENING.
&&
.POINT TEMPS/POPS...
DLH 36 22 34 22 / 20 10 10 10
INL 32 21 34 20 / 50 20 20 10
BRD 36 24 38 20 / 10 10 10 0
HYR 39 24 36 21 / 10 10 10 0
ASX 38 25 36 23 / 20 20 10 10
&&
.DLH WATCHES/WARNINGS/ADVISORIES...
MN...WINTER WEATHER ADVISORY UNTIL NOON CST TODAY FOR MNZ010>012-
018>021-026.
WI...NONE.
&&
$$
SHORT TERM...KK
LONG TERM....GRANING
AVIATION...EOM
AREA FORECAST DISCUSSION
NWS GLASGOW MT
937 PM MST MON JAN 30 2012
.SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH WEDNESDAY...
OVERALL THE FORECAST IS IN GOOD SHAPE. ONLY TWEAKS WERE TO REFLECT
THE BACK EDGE OF THE PRECIPITATION AREA IN THE POP FORECAST. ALSO
PUT IN SOME LOW POTENTIAL FOR FREEZING RAIN AFTER MIDNIGHT ACROSS
THE SOUTHEAST AS TEMPS AT THE SURFACE MAY FALL BELOW FREEZING
BEFORE THE RAIN EXITS.
PREVIOUS DISCUSSION...A WEST TO NORTHWEST FLOW RESIDES OVER THE
AREA WITH A WEAK DISTURBANCE MOVING EAST THROUGH MONTANA TODAY.
RADAR ECHOES OVER THE STATE HAVE BEEN SPOTTY IN THE PAST 12 TO 18
HOURS BUT SOME INCREASES ARE SHOWING UP IN NORTH-CENTRAL MONTANA
AND A BIT INTO THE WESTERN AND CENTRAL ZONES EARLY THIS AFTERNOON.
THESE ECHOES ARE EXPECTED TO INCREASE IN INTENSITY INTO THE LATE
AFTERNOON THEN BEGIN TO DIMINISH THIS EVENING. THE NAM AND GFS
SHOW IT TO HIT MAINLY THE CENTRAL ZONES...AND HAVE INCREASED POPS
ACCORDINGLY. THE HRRR SHOWED IT PRODUCE THE GREATEST QPF OVER THE
SE ZONES THAN THE GFS. HAVE LEANED MORE WITH THE GFS THOUGH BASED
ON RECENT PERFORMANCE. THE NAM HAS BEEN MUCH TOO WET WITH RECENT
SYSTEMS. ALBEIT BRIEF...THE SYSTEM LOOKS INTENSE WITH MOST OF THE
LIFT OCCURRING JUST ABOVE 700 MB AND WHERE TEMPS ARE AROUND -15C
(AND GOOD DENDRITIC GROWTH). PRECIP TYPE LOOKS TRICKY WITH MODEL
NAM SOUNDINGS SHOWING A POSSIBLE MIX WITH SNOW WHILE THE GFS IS
WARMER AND KEEPS THE PRECIP ALL LIQUID.
SYSTEM PASSES OFF TO OUR SOUTHEAST TONIGHT. WITH POSSIBLE WET
ROADWAYS...CLEARING SKIES AND TEMPS DROPPING BELOW FREEZING...ICY
ROADS ARE A GOOD POSSIBILITY. HAVE HIGHLIGHTED THIS IN AN HWO.
AFTERWARDS...IT LOOKS TO REMAIN PARTLY CLOUDY WITH CONTINUED ABOVE
NORMAL TEMPS. WENT ABOVE MAV AND MET GUIDANCE ON TEMPS...CLOSER
TO BIAS CORRECTED NUMBERS. CLOUDS LOOK TO BEGIN INCREASING
WEDNESDAY AFTERNOON WITH THE NEXT SYSTEM COMING IN. JAMBA
.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...
MORE SPRING-LIKE WEATHER IN THE OFFING. IN THE MIDST OF AN
AMPLIFYING PATTERN...THE LAST IN A SERIES OF SHORTWAVES MOVES SE
ACROSS THE AREA WED NIGHT...WITH SOME SPLITTING MOTION THOUGH. WILL
RAISE POPS TO A SLIGHT CHANCE OF SNOW SHOWERS.
THEN...AN UNUSUALLY STRONG UPPER RIDGE TAKES HOLD OVER THE WESTERN
STATES...THEN CLOSING OFF A CENTER OVER THE NORTHERN ROCKIES TO
THE PACIFIC NW. THIS GIVES SEVERAL DAYS OF DRY AND MAINLY SUNNY
WEATHER...WITH WINDS ON THE LIGHT SIDE. TEMPS LIKELY TO REMAIN
WELL ABOVE NORMAL WITH THICKNESSES OFTEN IN THE 540S DM...BUT 850
MB FORECAST TEMPS AND MODEL SPECTRUM DO SHOW SIGNIFICANT
DIFFERENCES...SEEMING TO INDICATE POSSIBLE STRONG INVERSIONS.
WITHOUT SNOW COVER THOUGH...PREFER TO STAY ON THE WARM SIDE OF
GUIDANCE.
LATE IN THE PERIOD...SIGNS OF THE RIDGE SHARPENING...AND A LITTLE
FARTHER W. THIS MAY ALLOW AN ARCTIC COLD FRONT FROM THE N TO
BRUSH OUR AREA. MUCH MODEL DIFFERENCE ON TIMING...BEING ANYWHERE
FROM SUNDAY TO TUESDAY...AND ON INTENSITY OF THE FRONT AND UPPER
SUPPORT AS WELL. THEREFORE AM STAYING CONSERVATIVE AS IT IS STILL
OUT THERE ON DAYS 6 TO 8. SIMONSEN
PREVIOUS LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY... MODELS
CONTINUE TO INDICATE TRANSITION FROM ZONAL PATTERN TO A HIGH
AMPLITUDE BLOCKING PATTERN EARLY IN THE EXTENDED PERIOD. NEW
WRINKLE IS TAKING THE SHORTWAVE DROPPING THROUGH THE GREAT BASIN
WEDNESDAY/WEDNESDAY NIGHT AND DEVELOPING A CLOSED LOW OVER THE
SOUTHWEST STATES. RIDGE STILL EXPECTED OVER THE NORTHERN ROCKIES
BUT WILL GET CLOSED OR PINCHED OFF BY LOW TO THE SOUTH AND TROF IN
THE EAST PACIFIC.
INITIAL PUSH OF WARM AIR INTO THE REGION WITH RIDGE WILL GRADUALLY
MODERATE AS SHORTWAVES PUSH THROUGH THE TOP OF THE RIDGE. OVERALL
STILL EXPECTING WELL ABOVE NORMAL TEMPERATURES AND DRY CONDITIONS
THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK. EBERT
&&
.AVIATION...
MID LEVEL CEILINGS 4K FT TO 6K FT AGL SPREADING EASTWARD TONIGHT WITH
RAIN SHOWERS DEVELOPING TOWARD N DAKOTA. THESE WILL LIKELY TURN TO SNOW
SHOWERS LATE TONIGHT BEFORE ENDING...WHICH MAY REDUCE VISIBILITY TO
2 TO 4 MILES AND CEILINGS TO 2-3K FT AGL FOR A SHORT TIME. KEEP AN
EYE OUT FOR MVFR TO BORDERLINE IFR CONDITIONS THROUGH THE
OVERNIGHT HOURS. FOR TUESDAY...EXPECT VFR CONDITIONS WITH
SCATTERED TO BROKEN LAYERS ABOVE 8K FT AGL. SIMONSEN/BMICKELSON
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
414 PM EST WED FEB 1 2012
.SYNOPSIS...
COOLER AIR WILL WORK INTO CENTRAL NEW YORK AND NORTHEAST
PENNSYLVANIA TONIGHT. HIGH PRESSURE OVER SOUTH CENTRAL CANADA WILL
MOVE SLOWLY SOUTHEAST TOWARDS THE AREA ON THURSDAY AND FRIDAY...BUT A
FEW WEAK UPPER LEVEL IMPULSES WILL BRING PERIODS OF CLOUDS TO THE
REGION...WITH THE POSSIBILITY OF A FEW FLURRIES ACROSS CENTRAL NEW
YORK LATE FRIDAY AND FRIDAY NIGHT. FAIR AND DRY WEATHER IS
EXPECTED ON SATURDAY.
&&
.NEAR TERM /THROUGH THURSDAY/...
AS OF 2 PM...COOLER AIR FINALLY WORKING INTO WRN ZONES BEHIND THE
FNT. BREAKS HAVE DVLPD IN THE CLD COVER ACRS MUCH OF CENTRAL ENW
YORK AND NORTHEAST PA. ANY -SHRA ACTIVITY SHUD BE CONFINED TO THE
SYR/RME/WRN CATSKILLS THIS AFTN...WITH PSBLTY OF SOME -SHSN MIXING
IN ACRS NRN ONEIDA EARLY THIS EVNG. NOT ESPCLY COLD BEHIND THE
FNT...AND XPCT ANY ACTIVITY TO DSPT THIS EVNG AS INVERSION HGT
LOWERS. MDL PROFILES SHOW SOME LARGE DIFFS W/RESPCT TO CLD CVR TNGT.
GIVEN SAT TRENDS...XPCT LOWER STRATUS DECK TO MOV BACK INTO CNTRL
NY TNGT...AS UPR DECK ENCROACHES FROM THE WEST LATE. THIS IS XPCTD
TO RESULT IN PARTLY TO MOSTLY CLDY CONDITIONS ACRS THE FCST AREA
ON THU. LOWS MAINLY IN THE U20S TO L30S TNGT...WITH MAXES ON THU
FROM THE M30S TO A40.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
A QUIET FOR CNTRL NY AND NE PA. MDLS INDICATE A WEAK S/WV TROF
DROPPING SEWD INTO THE FCST AREA LATE FRI/FRI NGT. THIS WAVE...IN
CONBINATION WITH WEAK LAKE INFLUENCES...MAY BE ENUF TO TRIGGER
SOME FLURRIES (DRIZZLE?) LATE FRI FAR NRN ZONES...AND ACRS MUCH OF
CNTRL NY FRI NGT. HIGH PRES RIDGING IN FROM THE GTLAKES IS XPCTD
TO PROVIDE FAIR WEATHER ON SAT. MOS TEMP GUIDANCE FOR THIS PD
GNRLY LOOKED GOOD.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
4PM UPDATE...
ANOTHER MILD EXTENDED WITH A LACK OF SNOW. MODELS AGREE ON THIS
BUT NOT ON THE DETAILS. HPC SIDING WITH EURO AND CANADIAN WHICH
STALLS A SFC LOW OVER THE UPPER OHIO VALLEY BEFORE PUSHING IT
THROUGH THE REGION MONDAY. BY THAT TIME STORM WEAKENED WITH LIGHT
QPF. WARM TEMPERATURES AND AN UPPER LEVEL RIDGE WOULD AGAIN MEAN
A MIX OF RAIN AND SNOW. GFS IS MUCH MORE PROGRESSIVE WITH A LOW
MOVING ENE ACROSS THE MID ATLANTIC STATES SUNDAY MORNING. THIS
WOULD BRING SNOW TO AT LEAST NE PA SAT NGT AND SUN MORNING. EURO
HAS A LARGE SURFACE HIGH AT THIS TIME. BEHIND THE EURO MONDAY
STORM A WEAK SECONDARY COLD FRONT FOLLOWED BY WEAK LAKE EFFECT
SNOW TUE NGT AND WED. NOTHING LOOKS THAT IMPRESSIVE. MUCH
UNCERTAINTY ALSO. CAPPED POPS AT SLIGHT CHANCE.
&&
.AVIATION /21Z WEDNESDAY THROUGH MONDAY/...
18Z WED TO 18Z THU...TOUCHY AVIATION FORECAST THIS AFTERNOON
INTO TONIGHT...YET MOSTLY TALKING ABOUT TIMING DETAILS OF MVFR.
COLD FRONT AS OF 18Z IS JUST ABOUT TO EXIT EASTERN PART OF THE
AREA...THOUGH STILL WITH SOME LLWS FOR KRME INITIALLY UNTIL IT
FULLY EXITS. DRY AIR AT MID LEVELS IS COMPETING WITH LAKE MOISTURE
TRAPPED UNDER DEVELOPING INVERSION AS WIND VEERS TO WNW...SO MANY
SITES WILL TEETER BACK AND FORTH BETWEEN SCT AND BKN MVFR CLOUDS.
MODELS ARE CHALLENGED TO RESOLVE THE INVERSION AND TRAPPED
MOISTURE...AND GIVEN UPSTREAM CONDITIONS...THE RUC SEEMS TO HAVE
BEST HANDLE. THUS FOR MOST SITES...PREDOMINANT MVFR RETURNS BACK
INTO THE AREA THIS EVENING...AT LEAST FOR NY TERMINALS. AS
INVERSION BECOMES SHALLOWER...WILL HAVE TO WATCH FOR SURPRISE IFR
OVERNIGHT FOR AT LEAST LAKE PLAIN /KSYR-KRME/...IT WILL BE IFFY.
IN THE END THOUGH...HIGH CLOUDS STREAM IN AHEAD OF NEXT WEAK WAVE
08Z ONWARD...WHICH SHOULD WEAKEN THE INVERSION AND ALLOW LOWER
CIGS TO SCATTER OUT. SOME UNCERTAINTY AS TO EXACT TIMING FOR THIS.
.OUTLOOK...
THUR AFTN/FRI...MVFR CIGS FOR NY TERMINALS THURSDAY NGHT/FRI MRNG.
FRI NGT/SAT...MVFR CIGS/VIS POSSIBLE FROM LAKE EFFECT FLURRIES FOR
CENTRAL NY TERMINALS FRI NGT INTO SAT MRNG. PATCHY -FZDZ NOT OUT
OF THE QUESTION FOR SAME SITES.
SAT NGT/SUN/SUN NGT...VFR.
MON...MVFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...TAC
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
200 PM EST WED FEB 1 2012
.SYNOPSIS...
COOLER AIR WILL WORK INTO CENTRAL NEW YORK AND NORTHEAST
PENNSYLVANIA TONIGHT. HIGH PRESSURE OVER SOUTH CENTRAL CANADA WILL
MOVE SLOWLY SOUTHEAST TOWARDS THE AREA ON THURSDAY AND FRIDAY...BUT A
FEW WEAK UPPER LEVEL IMPULSES WILL BRING PERIODS OF CLOUDS TO THE
REGION...WITH THE POSSIBILITY OF A FEW FLURRIES ACROSS CENTRAL NEW
YORK LATE FRIDAY AND FRIDAY NIGHT. FAIR AND DRY WEATHER IS
EXPECTED ON SATURDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 2 PM...COOLER AIR FINALLY WORKING INTO WRN ZONES BEHIND THE
FNT. BREAKS HAVE DVLPD IN THE CLD COVER ACRS MUCH OF CENTRAL ENW
YORK AND NORTHEAST PA. ANY -SHRA ACTIVITY SHUD BE CONFINED TO THE
SYR/RME/WRN CATSKILLS THIS AFTN...WITH PSBLTY OF SOME -SHSN MIXING
IN ACRS NRN ONEIDA EARLY THIS EVNG. NOT ESPCLY COLD BEHIND THE
FNT...AND XPCT ANY ACTIVITY TO DSPT THIS EVNG AS INVERSION HGT
LOWERS. MDL PROFILES SHOW SOME LARGE DIFFS W/RESPCT TO CLD CVR TNGT.
GIVEN SAT TRENDS...XPCT LOWER STRATUS DECK TO MOV BACK INTO CNTRL
NY TNGT...AS UPR DECK ENCROACHES FROM THE WEST LATE. THIS IS XPCTD
TO RESULT IN PARTLY TO MOSTLY CLDY CONDITIONS ACRS THE FCST AREA
ON THU. LOWS MAINLY IN THE U20S TO L30S TNGT...WITH MAXES ON THU
FROM THE M30S TO A40.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
A QUIET FOR CNTRL NY AND NE PA. MDLS INDICATE A WEAK S/WV TROF
DROPPING SEWD INTO THE FCST AREA LATE FRI/FRI NGT. THIS WAVE...IN
CONBINATION WITH WEAK LAKE INFLUENCES...MAY BE ENUF TO TRIGGER
SOME FLURRIES (DRIZZLE?) LATE FRI FAR NRN ZONES...AND ACRS MUCH OF
CNTRL NY FRI NGT. HIGH PRES RIDGING IN FROM THE GTLAKES IS XPCTD
TO PROVIDE FAIR WEATHER ON SAT. MOS TEMP GUIDANCE FOR THIS PD
GNRLY LOOKED GOOD.
&&
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
4AM UPDATE...
THE MODELS CONTINUE TO BE IN DECENT AGREEMENT OVER THE UPCOMING
WEEKEND IN THAT IT SHOULD BE FAIRLY QUIET. THE MAIN DIFFERENCE IS
THE GFS DROPS A CHUNK OF COLDER AIR ACROSS OUR AREA SUNDAY...WHILE
THE EURO IS MUCH FARTHER EAST WITH THIS SHOT OF COLD AIR. IF THE GFS
PANS OUT WE MAY SEE SEE A FEW LAKE FLURRIES BUT FOR CONSISTENCY WILL
KEEP WITH A DRY AND NOT AS COLD FORECAST...WHICH IS MORE IN LINE
WITH HPC AND OUR GOING FORECAST.
EARLY NEXT WEEK IS STILL VERY UNCERTAIN. UNLIKE 24 HOURS AGO...THE
GFS IS NOW DRY THROUGH THE MIDDLE OF THE WEEK WHILE TURNING COOLER.
THE 0Z EURO...ALSO SHOWING SOME RUN TO RUN INCONSISTENCY...IS BACK
ON AGAIN WITH A WET SYSTEM FOR MONDAY. ALTHOUGH NOT EXACTLY THE
SAME...THE CANADIAN ALSO SHOWS A TROF IN THE EAST AND WOULD SUPPORT
THE SOLUTION OF RAIN AROUND FOR MONDAY. IN ADDITION SOME OF THE GFS
ENSEMBLES SHOW PRECIP AROUND FOR THE START OF THE WEEK SO I WILL
INTRODUCE SLIGHT CHANCE TO LOW CHANCE POPS FOR MONDAY...BEFORE A
GRADUAL COOLER TREND TO SNOW SHOWERS BY THE MIDDLE OF NEXT WEEK.
&&
.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
18Z WED TO 18Z THU...TOUCHY AVIATION FORECAST THIS AFTERNOON
INTO TONIGHT...YET MOSTLY TALKING ABOUT TIMING DETAILS OF MVFR.
COLD FRONT AS OF 18Z IS JUST ABOUT TO EXIT EASTERN PART OF THE
AREA...THOUGH STILL WITH SOME LLWS FOR KRME INITIALLY UNTIL IT
FULLY EXITS. DRY AIR AT MID LEVELS IS COMPETING WITH LAKE MOISTURE
TRAPPED UNDER DEVELOPING INVERSION AS WIND VEERS TO WNW...SO MANY
SITES WILL TEETER BACK AND FORTH BETWEEN SCT AND BKN MVFR CLOUDS.
MODELS ARE CHALLENGED TO RESOLVE THE INVERSION AND TRAPPED
MOISTURE...AND GIVEN UPSTREAM CONDITIONS...THE RUC SEEMS TO HAVE
BEST HANDLE. THUS FOR MOST SITES...PREDOMINANT MVFR RETURNS BACK
INTO THE AREA THIS EVENING...AT LEAST FOR NY TERMINALS. AS
INVERSION BECOMES SHALLOWER...WILL HAVE TO WATCH FOR SURPRISE IFR
OVERNIGHT FOR AT LEAST LAKE PLAIN /KSYR-KRME/...IT WILL BE IFFY.
IN THE END THOUGH...HIGH CLOUDS STREAM IN AHEAD OF NEXT WEAK WAVE
08Z ONWARD...WHICH SHOULD WEAKEN THE INVERSION AND ALLOW LOWER
CIGS TO SCATTER OUT. SOME UNCERTAINTY AS TO EXACT TIMING FOR THIS.
.OUTLOOK...
THUR AFTN/FRI...MVFR CIGS FOR NY TERMINALS THURSDAY NGHT/FRI MRNG.
FRI NGT/SAT...MVFR CIGS/VIS POSSIBLE FROM LAKE EFFECT FLURRIES FOR
CENTRAL NY TERMINALS FRI NGT INTO SAT MRNG. PATCHY -FZDZ NOT OUT
OF THE QUESTION FOR SAME SITES.
SAT NGT/SUN...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
LONG TERM...HEDEN
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1255 PM EST WED FEB 1 2012
.SYNOPSIS...
A WEAK COLD FRONT WILL CROSS THE AREA THIS MORNING BRINGING
SCATTERED SHOWERS THROUGH MIDDAY. TONIGHT THROUGH FRIDAY, WILL BE
DRY WITH TEMPERATURES RETURNING TO MORE SEASONAL LEVELS.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
UPDATED AT 920 AM...CR NT FCST IN FINE SHAPE. RAISED TEMPS FOR THE
LATE MRNG INTO THE AFTN HRS AS MAIN COOLING WILL BE DELAYED UNTIL
LATER THIS AFTN. ALSO MADE SOME TWEAKS TO SKY CVR. TREND FOR
DCRSNG POPS LOOKS GOOD AS MAIN BATCH OF -SHRA WILL BE EXITING BY
LATE MRNG. PREV BLO...
645 UPDATE...CONVECTION AHEAD OF BOUNDARY CURRENTLY MOVING ACROSS
CENTRAL NEW YORK. UPPED POPS TO LIKELY (WIDESPREAD) OVER MUCH OF
THE AREA FOR THE NEXT COUPLE OF HOURS. NO OTHER CHANGES.
AT 415 AM A SFC COLD FRONT EXTENDED FROM GEORGIAN BAY SOUTHWEST TO
DETROIT. SCATTERED SHOWERS WERE OCCURRING AHEAD OF THIS BOUNDARY
WITH MORE WIDESPREAD COVERAGE ACROSS WESTERN NEW YORK DUE TO
MOISTURE ENHANCEMENT FROM LAKE ERIE.
THE COLD FRONT WILL CROSS THE AREA BETWEEN 15Z-19Z WITH SCATTERED
SHOWERS EXPECTED AHEAD OF THIS FEATURE. AFTER THE FRONT PASSES
THIS SHOWERY ACTIVITY WILL END AND WITH STRONG DRY AIR ADVECTION
SKIES WILL QUICKLY BECOME PARTLY TO MOSTLY SUNNY.
TEMPS WILL RANGE FROM THE MID 40S TO AROUND 50 THIS MORNING THEN
GRADUALLY FALL THIS AFTERNOON INTO THE LOWER 40S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
A MEAN UPPER LEVEL TROF WILL REMAIN OVER THE NORTHEAST THROUGH
FRIDAY NIGHT WITH DRY CONDITIONS AND TEMPS RETURNING TO MORE
SEASONAL VALUES BUT STILL AROUND 5 DEGREES ABOVE NORMAL. A
SOUTHERN STREAM SYSTEM PASSING TO OUR SOUTH LATE TONIGHT AND
THURSDAY MORNING WILL BRING MID LEVEL CLOUDS TO THE AREA. THURSDAY
NIGHT AND FRIDAY WILL BE PARTLY CLOUDY WITH SFC HIGH PRES IN THE VCNTY.
FRIDAY NIGHT, A WEAK SFC TROF PASSING THROUGH NRN NY WILL BRING
MORE CLOUDS TO THE REGION AND ALONG WITH SLIGHTLY COOLER T85 THE
CHANCE FOR SOME SNOW FLURRIES OFF LAKE ONTARIO WITH A 300 FLOW.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
4AM UPDATE...
THE MODELS CONTINUE TO BE IN DECENT AGREEMENT OVER THE UPCOMING
WEEKEND IN THAT IT SHOULD BE FAIRLY QUIET. THE MAIN DIFFERENCE IS
THE GFS DROPS A CHUNK OF COLDER AIR ACROSS OUR AREA SUNDAY...WHILE
THE EURO IS MUCH FARTHER EAST WITH THIS SHOT OF COLD AIR. IF THE GFS
PANS OUT WE MAY SEE SEE A FEW LAKE FLURRIES BUT FOR CONSISTENCY WILL
KEEP WITH A DRY AND NOT AS COLD FORECAST...WHICH IS MORE IN LINE
WITH HPC AND OUR GOING FORECAST.
EARLY NEXT WEEK IS STILL VERY UNCERTAIN. UNLIKE 24 HOURS AGO...THE
GFS IS NOW DRY THROUGH THE MIDDLE OF THE WEEK WHILE TURNING COOLER.
THE 0Z EURO...ALSO SHOWING SOME RUN TO RUN INCONSISTENCY...IS BACK
ON AGAIN WITH A WET SYSTEM FOR MONDAY. ALTHOUGH NOT EXACTLY THE
SAME...THE CANADIAN ALSO SHOWS A TROF IN THE EAST AND WOULD SUPPORT
THE SOLUTION OF RAIN AROUND FOR MONDAY. IN ADDITION SOME OF THE GFS
ENSEMBLES SHOW PRECIP AROUND FOR THE START OF THE WEEK SO I WILL
INTRODUCE SLIGHT CHANCE TO LOW CHANCE POPS FOR MONDAY...BEFORE A
GRADUAL COOLER TREND TO SNOW SHOWERS BY THE MIDDLE OF NEXT WEEK.
&&
.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
18Z WED TO 18Z THU...TOUCHY AVIATION FORECAST THIS AFTERNOON
INTO TONIGHT...YET MOSTLY TALKING ABOUT TIMING DETAILS OF MVFR.
COLD FRONT AS OF 18Z IS JUST ABOUT TO EXIT EASTERN PART OF THE
AREA...THOUGH STILL WITH SOME LLWS FOR KRME INITIALLY UNTIL IT
FULLY EXITS. DRY AIR AT MID LEVELS IS COMPETING WITH LAKE MOISTURE
TRAPPED UNDER DEVELOPING INVERSION AS WIND VEERS TO WNW...SO MANY
SITES WILL TEETER BACK AND FORTH BETWEEN SCT AND BKN MVFR CLOUDS.
MODELS ARE CHALLENGED TO RESOLVE THE INVERSION AND TRAPPED
MOISTURE...AND GIVEN UPSTREAM CONDITIONS...THE RUC SEEMS TO HAVE
BEST HANDLE. THUS FOR MOST SITES...PREDOMINANT MVFR RETURNS BACK
INTO THE AREA THIS EVENING...AT LEAST FOR NY TERMINALS. AS
INVERSION BECOMES SHALLOWER...WILL HAVE TO WATCH FOR SURPRISE IFR
OVERNIGHT FOR AT LEAST LAKE PLAIN /KSYR-KRME/...IT WILL BE IFFY.
IN THE END THOUGH...HIGH CLOUDS STREAM IN AHEAD OF NEXT WEAK WAVE
08Z ONWARD...WHICH SHOULD WEAKEN THE INVERSION AND ALLOW LOWER
CIGS TO SCATTER OUT. SOME UNCERTAINTY AS TO EXACT TIMING FOR THIS.
.OUTLOOK...
THUR AFTN/FRI...MVFR CIGS FOR NY TERMINALS THURSDAY NGHT/FRI MRNG.
FRI NGT/SAT...MVFR CIGS/VIS POSSIBLE FROM LAKE EFFECT FLURRIES FOR
CENTRAL NY TERMINALS FRI NGT INTO SAT MRNG. PATCHY -FZDZ NOT OUT
OF THE QUESTION FOR SAME SITES.
SAT NGT/SUN...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...RRM
NEAR TERM...RRM
SHORT TERM...RRM
LONG TERM...HEDEN
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1250 AM EST TUE JAN 31 2012
.SYNOPSIS...
A WARM FRONT WILL CROSS THE REGION OVERNIGHT...BRINGING A SHOT OF
LIGHT SNOW. IN THE WAKE OF THIS SYSTEM...MILDER TEMPERATURES WILL
BE WITH US ON TUESDAY AND WEDNESDAY. THE BEST CHANCE OF LIGHT RAIN
DURING THIS TIME FRAME WILL BE TUESDAY NIGHT INTO WEDNESDAY...WHEN
A WEAK COLD FRONT CROSSES CENTRAL NEW YORK AND NORTHEAST
PENNSYLVANIA.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
10PM UPDATE...FORECAST IS STILL ON TRACK WITH A WARM FRONT MOVING
THROUGH TONIGHT. IT IS CURRENTLY BRINGING SOME LIGHT SNOW SHOWERS
TO THE CWA. THE HRRR AND THE RUC SEEM TO BE HANDLING IT QUITE
WELL. OTHER MODELS ALSO LOOK TO BE IN GOOD AGREEMENT. THIS FRONT
WILL LIFT OUT OVER THE NEXT SEVERAL HOURS, TAKING THE SNOW SHOWERS
WITH IT. HAVE BACKED OF ON POPS BEHIND THE FRONT AS ALL MODELS
HAVE THE PRECIP ENDING IN THE EARLY MORNING HOURS. STILL KEPT IN
SOME LOW POPS FOR AN ISOLATED SHOWER, BUT PROBABLY WONT BE MORE
THEN SOME FLURRIES. LOOKING UPSTREAM, TEMPS ARE ALREADY BEGINNING
TO VERY SLOWLY RISE IN WESTERN PA. THIS SHOULD BE THE OVERALL TREND
TONIGHT BEHIND THE FRONT. THIS WILL ALLOW SOME VERY WARM TEMPS TO
COME IN TOMORROW, AND IF ANY SUN BREAKS OUT, TEMPS COULD BE HIGHER
THAN FORECAST. THIS WILL ALLOW ANY PRECIP THAT DOES FALL TOMORROW
TO CHANGE OVER TO RAIN, MAINLY AFTER DAYBREAK.
4 PM UPDATE... OVERRUNNING/WAA LGT SNOW IS ALREADY ENTERING WRN NY
ATTM. THIS PCPN SHIELD WILL MAKE STEADY EWD PROGRESS THE NEXT FEW
HRS...AND SHOULD ENVELOPE MUCH OF THE FA (EXCEPT PERHAPS THE FAR
SRN ZNS)...BY 00-02Z. THE SUPPORTING AREA OF ISEN LIFT...DUE TO
ITS RAPID MOVEMENT HOWEVER...WILL ALSO EXIT MOST OF THE CWA JUST
ABT AS QUICKLY. THUS...WE`RE LOOKING FOR STEADIER -SN TO TAPER OFF
ACRS THE TWIN TIERS BY 04-07Z...WITH -SN PROBABLY HANGING ON UNTIL
EARLY TUE IN THE FAR N. IN GENERAL...AN INCH OR LESS IS EXPECTED
OVER THE TWIN TIERS...WITH 1-3" ACRS THE NRN FINGER LKS...THE SRN
TUG HILL RGN...AND THE WRN MOHAWK VLY.
TEMPS WILL EXHIBIT A NON-DIURNAL TREND OVERNIGHT...GENERALLY
RISING SLOWLY AFTER ABT 02-03Z. IN FACT...IN SOME OF OUR NORMALLY
MILDER LAKE PLAIN AREAS...TEMPS SHOULD INCH ABV FRZG LATE
TNT...AND A -RA/-SN MIX COULD OCCUR IN THESE LOCALES.
PREV DISC... 1 PM UPDATE... THE LES ADVSY HAS EXPIRED ON
SCHEDULE. LOW- LVL WAA AND BACKING FLOW HAVE TAKEN THEIR
TOLL...AND THE BAND CONTINUES TO LOOK LESS ORGANIZED ATTM.
THE ONLY OTHER CHGS THIS UPDATE WERE MINOR TWEAKS TO EARLY TO MID-
AFTN TEMPS AND OUR MAX TEMP GRID.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY/...
410 PM UPDATE... THE LOW-LVL WARM FRNT SHOULD REMAIN NEARLY
STATIONARY JUST N OF THE FA TUE AND TUE EVE. THE BEST CHC FOR ANY
-RA/-DZ WILL BE UP CLOSER TO THIS BNDRY...ACRS OUR NRN/ERN ZNS.
ELSEWHERE...CONDS SHOULD STAY LARGELY PCPN-FREE.
A MUCH MILDER AMS WILL BUILD IN ON TUE...AND EVEN WITH ABUNDANT
CLD COVER...HIGHS SHOULD REACH WELL INTO THE 40S...AND MAY TOUCH
50 OVER SXNS OF NE PA. IF ANY SUNSHINE WERE TO BREAK
THROUGH...READINGS COULD GET EVEN WARMER (WELL INTO THE 50S)...BUT
THIS WILL PROBABLY BE TOUGH...GIVEN ALL THE LOW-LVL MOIST IN
PLACE.
TUE NGT...AS A FAST MOVG UPPER TROUGH AND WEAK SFC WAVE MOVE ACRS
ONT/QUE...A COLD FRONT WILL CROSS CNY/NE PA FROM NW TO SE. SCTD
-SHRA SHOULD ACCOMPANY THIS SYSTEM...AS IT APPCHS AND PUSHES
THROUGH.
WED AND WED NGT...VERY WEAK CAA WILL ENSUE BEHIND THE
FRNT...LIKELY INSUFFICIENT FOR ANY REAL LAKE RESPONSE. BY THU...A
SRN STREAM SYSTEM IS PROGGED TO TRACK FM THE LWR MS VLY ENEWD INTO
THE SERN STATES. ALTHOUGH THERE IS CERTAINLY MODEL UNCERTAINTY IN
THE POSITIONING/EVOLUTION OF THIS SYSTEM...CURRENT CONSENSUS
SUGGESTS IT WILL STAY PRIMARILY S OF THE FA. FOR NOW...WE BRING IN
A CHANCE OF -RA/-SN...MOSTLY ACRS NE PA.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
MODELS BEGIN IN DECENT AGREEMENT FOR THE EXTENDED FORECAST PERIOD.
THE GFS AND THE ECMWF, BOTH SHOW A WEAK UPPER LEVEL TROUGH OVER
THE CWA AT 00Z FRIDAY. THEY BOTH THEN SHOW A FLAT UPPER LEVEL
RIDGE BUILDING BY 00Z SAT. MODELS THEN DIVERGE FOR THE WEEKEND.
THE GFS HAS A SFC RIDGE BUILDING, KEEPING THE AREA MOSTLY DRY,
WITH POSSIBLY SOME LAKE EFFECT FLURRIES. THE ECMWF HAS A LOW
PRESSURE SYSTEM SKIMMING BY THE CWA TO THE SOUTH AND GOING OUT TO
SEA. THE ECMWF HAS BEEN BOUNCING SYSTEMS ALL OVER LATELY, WHICH
HAS BROUGHT CONFIDENCE DOWN IN ITS SOLUTIONS, SO HAVE KEPT POPS
BELOW SLIGHT CHANCE FOR NOW.
BY SUNDAY NIGHT, BOTH MODELS HAVE SOME TYPE OF SYSTEM DEVELOPING
AND MOVING NEAR THE AREA. THE GFS HAS A STRONG LOW OVER THE GREAT
LAKES AND RAIN MOVING INTO THE CWA MONDAY NIGHT WITH A CHANGE TO
MIXED AND THEN SNOW, BEHIND A COLD FRONT BY MONDAY AFTERNOON. THE
ECMWF HAS A WEAK LOW MOVING OF THE COAST OF SOUTHERN NJ AND THEN
OUT TO SEA. IT BRINGS SOME LIGHT SNOW TO THE AREA. HAVE CHC POPS
FOR SUNDAY NIGHT AND DROP TO SLIGHT CHC FOR MOST OF THE CWA
MONDAY, WITH A MIX OF SNOW/RAIN AS THE PTYPE.
HIGH TEMPS FOR THE WEEKEND AND BEGINNING OF THE WEEK LOOK TO BE
ABOVE NORMAL, REACHING INTO THE MID TO UPPER 30S, TO POSSIBLY
AROUND FOR IN NEPA. LOWS EACH NIGHT LOOK TO BE IN THE MID 20S.
SUNDAY NIGHT DOES LOOK AS THOUGH WARM ADVECTION WILL CAUSE A NON
DIURNAL CYCLE, WITH THE LOW HAPPENING IN THE LATE EVENING, EARLY
MORNING HOURS, IF THE GFS IS CORRECT.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
1 AM UPDATE...
THE BACK EDGE OF SNOW IS ALMOST THROUGH KRME...WITH SOME IFR
POSSIBLE HERE FOR ABOUT ANOTHER 30 MINUTES OR SO. OBSERVATIONS
BACK TO THE WEST AT KSYR AND KFZY ARE ALREADY VFR SO EXPECT
IMPROVING CONDITIONS AT KRME TO MOVE IN SOON.
ELSEWHERE VFR CONDITIONS ARE EXPECTED TODAY AS A DECK OF CLOUDS
AROUND 10KFT NOW SLOWLY ERODES TOWARD DAYBREAK ACROSS THE
SOUTHERN 2/3RDS OF THE TERMINALS...AND BY MID-MORNING ACROSS THE
FAR NORTH. SOME MOISTURE MAY TRY TO REFORM EARLY TONIGHT...PERHAPS
EVEN PRODUCING MVFR CIGS LATER TONIGHT...BUT TOO LITTLE CONFIDENCE
TO INCLUDE IN THE TAFS AT THIS MOMENT.
WINDS WILL BE OUT OF THE SOUTH/SOUTHWEST AT 5 TO 10 KTS THROUGH
THE END OF THE TAF PERIOD...EXCEPT LIGHT EAST-SOUTHEAST AT KRME.
.OUTLOOK...
WED...MVFR. OCCASIONAL RAIN SHOWERS.
WED NIGHT...VFR.
THUR...VFR. CHC MVFR SNOW SHOWERS VCNTY KSYR-KRME.
FRI THRU SAT...VFR.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MLJ
NEAR TERM...MLJ/SLI
SHORT TERM...MLJ
LONG TERM...SLI
AVIATION...HEDEN
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
912 PM EST WED FEB 1 2012
.SYNOPSIS...
A COLD FRONT WILL MOVE ACROSS THE AREA THURSDAY MORNING...BRINGING A
PERIOD OF MAINLY LIGHT RAIN. HIGH PRESSURE WILL BUILD INTO THE
CAROLINAS FROM THE NORTH FRIDAY AND SATURDAY...BRINGING COLDER
TEMPERATURES. A LOW PRESSURE SYSTEM APPROACHING FROM THE WEST MAY
BRING MORE RAIN LATE IN THE WEEKEND INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 9 PM WEDNESDAY...THE LAST FIVE RUNS OF THE HRRR HAVE BEEN VERY
VERY CONSISTENT REGARDING THE LITERAL EVAPORATION OF THE AREA OF
RAIN ADVANCING EAST ACROSS SOUTH CAROLINA. LATEST RADAR TRENDS ARE
BEARING THIS OUT...SHOWING THE HEAVIER RADAR RETURNS DIMINISHING IN
BOTH AREA AND INTENSITY. WHY IS THIS OCCURRING? THE MOISTURE-BEARING
LAYER PRODUCING THE PRECIPITATION IS LOCATED BETWEEN 750-550 MB...
APPROXIMATELY 8000-15000 FT ABOVE GROUND LEVEL. THERE IS ONLY WEAK
ISENTROPIC UPGLIDE THROUGH THIS LAYER INFERRING SMALL VERTICAL
VELOCITIES AND PRECIPITATION GENERATION. BELOW THIS CLOUD BASE THERE
IS A SIGNIFICANT AMOUNT OF DRY AIR WITH NAM AND GFS FORECAST
SOUNDINGS SHOWING DEWPOINT DEPRESSIONS AS LARGE AS 25 DEGREES F
AROUND 6000 FT AGL. THESE FACTORS POINT TO VERY LIGHT PRECIPITATION
AMOUNTS OVERNIGHT. IN FACT...THE ODDS OF ACTUALLY RECORDING A TRUE
0.01" IN YOUR RAIN GAUGE ARE NOT EVEN 50/50 AT THIS TIME. WE HAVE
TRIMMED BACK OUR POPS ACCORDINGLY.
SYNOPTICALLY...A SURFACE COLD FRONT ACROSS CENTRAL TENNESSEE INTO
EASTERN MISSISSIPPI WILL MOVE EAST OVERNIGHT...REACHING THE EASTERN
CAROLINAS THURSDAY MORNING. TEMPERATURES WILL REMAIN WELL ABOVE
NORMAL OVERNIGHT WITH CLOUDS AND A RATHER WARM AIRMASS AHEAD OF THE
FRONT. LOWS SHOULD RANGE 53-58...WARMEST AT THE SOUTH-FACING
BEACHES. (NORMAL LOWS FOR FEB 2 ARE IN THE MID TO UPPER 30S!)
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 PM WEDNESDAY...THE SHORT WAVE TROUGH MOVING ACROSS THE
DEEP SOUTH WILL BE EXITING THE REGION AROUND 12 UTC AND A
LINGERING SHOWER OR TWO IS POSSIBLE CLOSER TO COAST EAST OF A
MYRTLE BEACH TO ELIZABETHTOWN LINE. ALL LAND AREAS SHOULD BE
PRECIPITATION FREE BY 15 UTC AND SKIES WILL BE CLEARING.
PRECIPITATION TOTALS ARE EXPECTED TO REMAIN LOW IN THIS EVENT.
AS THE COLD FRONT PUSHES OFFSHORE HIGH PRESSURE IS FORECAST BY BOTH
THE NAM AND GFS TO BUILD SOUTHWARD ALONG THE LEE OF THE APPALACHIAN
MOUNTAINS. AT THIS TIME NO PRECIPITATION IS EXPECTED BETWEEN
THURSDAY AFTERNOON AND FRIDAY NIGHT. NO SIGNIFICANT WEATHER IS
EXPECTED TO OCCUR IN THE LAST 36 HOURS OF THIS FORECAST PERIOD.
THE MAXIMUM TEMPERATURES ARE EXPECTED TO BE IN THE LOWER 70S WITH
THE WEST WINDS ON THURSDAY BEHIND THE FRONT. HIGHS ARE EXPECTED ONLY
TO REACH THE LOWER 60S WITH THE BEST COLD AIR ADVECTION NOT EXPECTED
INTO THE AREA UNTIL THURSDAY NIGHT. LOW TEMPERATURES ARE EXPECTED
TO FALL INTO THE LOWER 40S INLAND AND MID 40S ALONG THE IMMEDIATE
BEACHES.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 3 PM WEDNESDAY...HIGH PRESSURE INIT OVER THE REGION SAT BUT
WILL BE PROGRESSING EAST ALLOWING FOR MOISTURE ADV AS THE DAY WEARS
ON. SAT NIGHT WARM FRONT SIG SEEN DEVEL IN PREV GUIDANCE NOW HARDER
TO MAKE OUT AND QUITE A BIT FARTHER NORTH. WILL CONTINUE LOW POPS
GRADED NW TO SE BUT LOWER. COLD FRONT SWEEPS THROUGH SUNDAY MIDDAY
OR EARLY PM. GOOD DYNAMICS NOT TOO FAR TO THE N SO ONCE AGAIN POPS
GRADED...THIS TIME HIGHEST N. UPPER TROUGH DEEPENS OFF NE COAST
MONDAY DRIVING SFC HIGH INTO THE SE ACCORD TO GFS WHILE OLDER ECMWF
IS FARTHER EAST AND QUICKER TO IMPLY WAA LOCALLY.SOME TEMP
RAMIFICATIONS THERE BUT ALSO A QUESTION REGARDING MOISTURE RECOVERY
AHEAD OF A WEAK SYSTEM FOR TUES. PREFER THE DRIER SOLNS AT THIS TIME
IF NOTHING ELSE GIVEN THE CURRENT DROUGHT.
&&
.AVIATION /00Z WEDNESDAY THROUGH MONDAY/...
AS OF 00Z...CLOUDS CLOSING IN ON THE TERMINALS AS PER THE SATELLITE
LOOP FROM THE WEST...EXPECT SOME MID LEVEL CLOUDS TO AFFECT THE
TERMINALS BETWEEN 00Z AND 02Z WITH LOW CHANCE FOR SOME STRATOCUMULUS
AS WELL. CLOUDS WILL LOWER AND THICKEN ACROSS THE TERMINALS DURING
THE OVERNIGHT PERIOD AS A COLD FRONT APPROACHES FROM THE WEST.
PRECIPITATION AHEAD AND ALONG THE FRONT WILL MOVE INTO THE REGION
TONIGHT AND OVERNIGHT. THE RAIN IS EXPECTED TO BE LIGHT MOST LIKELY
LESS THAN A TENTH OF AN INCH WITH A ISOLATED AREA OR TWO WITH SOME
HEAVIER SHOWERS...MAINLY INLAND. INLAND TERMINALS TO DROP FROM VFR
TO MVFR BETWEEN 04Z-08Z MAINLY IN CEILINGS WITH THE COASTAL
TERMINALS DROPPING INTO MVFR CATEGORY BETWEEN 07Z-11Z WITH CEILINGS
AS WELL. COULD SEE IFR/LIFR IN CEILINGS AND FOG IN TEMPO GROUPS
BETWEEN 12Z-15Z FROM INLAND TO COAST JUST AHEAD OF THE COLD FRONT.
SW WINDS WILL PREVAIL AHEAD OF THE FRONT ALL TERMINALS WITH WINDS
VEERING TO THE WEST AFTER 15Z AND THEN NW AFTER 18Z. FROPA IS
EXPECTED BY 14Z ACROSS FLO AND LBT AND AFTER 15Z FOR THE 3 COASTAL
TERMINALS. CEILINGS IMPROVE RAPIDLY AFTER FROPA BECOMING VFR ALL
TERMINALS.
EXTENDED OUTLOOK...LOW CONFIDENCE FOR IFR ASSOCIATED WITH RAIN LATE
SATURDAY INTO EARLY SUNDAY. OTHERWISE VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 9 PM WEDNESDAY...A WEAK COLD FRONT WILL APPROACH FROM THE
WEST LATE TONIGHT...PROBABLY WAITING UNTIL AFTER DAYBREAK TO MOVE
OUT ACROSS THE COASTAL WATERS. SOUTHWEST WINDS OUT IN ADVANCE OF THE
FRONT WILL CONTINUE OVERNIGHT WITH WIND SPEEDS GENERALLY 10-15 KT
OVER THE COASTAL WATERS FORECAST AREA. THE SINGLE EXCEPTION TO THIS
MIGHT BE NEAR FRYING PAN SHOALS WHERE WARM WATER TEMPERATURES (AND
GRADUALLY WARMER AIR TEMPERATURES) POKE INTO OUR FORECAST AREA AND
MAY ALLOW STRONGER WIND SPEEDS TO MIX DOWN FROM ALOFT. SOME 15-20 KT
WINDS ARE POSSIBLE HERE...GENERALLY OUT BEYOND 15 MILES FROM SHORE.
AN AREA OF PATCHY LIGHT RAIN IN ADVANCE OF THE FRONT WILL MOVE
OFFSHORE AFTER MIDNIGHT.
SEAS ARE AREA BUOYS HAVE FINALLY BUILT TO 2 FEET. AWAY FROM THE
IMMEDIATE COAST SEAS WILL BUILD TO 2-3 FT OVERNIGHT...WITH SOME
4-FOOT SEAS POSSIBLE OUT BEYOND 10 MILES FROM SHORE IN THE FRYING
PAN SHOALS VICINITY.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 PM WEDNESDAY...THE SHORT TERM FORECAST PERIOD WILL BEGIN
WITH A COLD FRONT SWEEPING ACROSS THE MARINE WATERS BY LATE MORNING
THE SOUTHWEST WINDS OF 15 KNOTS WILL VEER TO THE WEST BY AFTERNOON
AND WILL SLOWLY DECREASE WITH TIME. AS HIGH PRESSURE WEDGES IN TO
THE LEE OF THE APPALACHIAN MOUNTAINS THE WINDS WILL CONTINUE TO VEER
TO THE NORTH AND NORTHEAST THURSDAY NIGHT INTO FRIDAY. WIND SPEEDS
WILL RUN BETWEEN 10 AND 15 KNOTS DURING THE TIME FRAME. FINALLY BY
FRIDAY NIGHT THE WINDS WILL BE SHIFTING TO THE EAST AND WILL RUN
AROUND 10 KNOTS.
SEAS WILL START OUT AT 3 TO 4 FT AND WILL SLOWLY FALL TO 2 TO 3 FEET
BY THURSDAY NIGHT. SEAS WILL INCREASE TO 3 TO 4 FEET FRIDAY TO
FRIDAY NIGHT AS NORTHEAST FLOW INCREASES WITH THE COLD AIR DAMMING
TO THE WEST.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 3 PM WEDNESDAY...LIGHT AND VEERING WINDS ON SAT AS SFC HIGH
PRESS SLIDES EAST ACRS THE MID-ATLANTIC JUST TO OUR N. WITH ONLY A
SMALL SWELL COMPONENT SEAS WILL BE PREDOMINANTLY WIND WAVES AND THUS
FAIRLY DIMINUTIVE...IN THE 2 TO 3 FT RANGE. A SHARPER VEER AND
PRONOUNCED INC IN SPEED THEN EXPECTED LATE SAT NIGHT AS HIGH MOVES
OFFSHORE AND COLD FRONT QUICKLY DRAWS NEAR...PINCHING THE GRAD
LOCALLY BETWEEN THE TWO. SEAS BUILD BUT THE SHORT DURATION OF HIGHER
WINDS AHEAD OF COLD FRONTAL PASSAGE APPEARS TO PRECLUDE ANY FLAGS AT
THIS TIME BUT CAUTIONARY HEADLINES APPEAR POSSIBLE. ANOTHER SHARP
VEER ASSOC WITH FROPA SUNDAY AFTERNOON TO CREATE A SHORT PERIOD OF
CONFUSION/CHOP TO WAVE FACES. UNCERTAINTY AT THIS TIME REGARDING HOW
LONG THE POST-FRONTAL PINCHED NE GRADIENT WINDS LAST BEFORE
SUBSIDING.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...HAWKINS
LONG TERM...MBB
AVIATION...MAC
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
632 PM EST WED FEB 1 2012
.SYNOPSIS...
A COLD FRONT WILL MOVE ACROSS THE AREA THURSDAY MORNING...BRINGING A
PERIOD OF MAINLY LIGHT RAIN. HIGH PRESSURE WILL BUILD INTO THE
CAROLINAS FROM THE NORTH FRIDAY AND SATURDAY...BRINGING COLDER
TEMPERATURES. A LOW PRESSURE SYSTEM APPROACHING FROM THE WEST MAY
BRING MORE RAIN LATE IN THE WEEKEND INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 630 PM WEDNESDAY...A SLUG OF LOW AND MID-LEVEL MOISTURE WILL
SLIDE EAST ACROSS THE AREA OVERNIGHT IN ADVANCE OF A WEAK SURFACE
COLD FRONT. RADAR COMPOSITES SHOW A BROKEN MASS OF MAINLY LIGHT RAIN
EXTENDING FROM THE CENTRAL CAROLINAS INTO NORTH GEORGIA MOVING EAST
AT AROUND 30 KNOTS. THE 18Z GFS AND NAM PAINT THIS MASS OF PRECIP
MOVING OVERHEAD AND OFFSHORE BY 12Z/7 AM THURSDAY. THE LATEST RUNS
OF THE RUC AND HRRR EVAPORATE A GOOD DEAL OF THE LIGHTER...
PERIPHERAL PRECIPITATION BEFORE IT MAKES IT INTO THE EASTERN
CAROLINAS...SUGGESTING THAT WHILE MOST FOLKS COULD STILL PICK UP A
FEW HUNDREDTHS OF AN INCH IN THEIR RAIN GAUGE THE ACTUAL TIME SPENT
RAINING MAY NOT BE SUBSTANTIAL. WE`RE GOING WITH THIS IDEA OF A
FAIRLY WIDESPREAD BUT VERY LOW IMPACT RAIN EVENT WITH STORM-TOTAL
PRECIPITATION AROUND ONE-TENTH OF AN INCH OR LESS. COVERAGE IS
FORECAST TO BE 60-80 PERCENT...HIGHEST INLAND AND LOWEST AT THE
COAST.
NO SIGNIFICANT CHANGES HAVE BEEN MADE TO OTHER FORECAST VARIABLES.
DEWPOINTS...WINDS AND SKY COVER WERE BLENDED WITH THE LATEST
SHORT-TERM MODELS.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 PM WEDNESDAY...THE SHORT WAVE TROUGH MOVING ACROSS THE
DEEP SOUTH WILL BE EXITING THE REGION AROUND 12 UTC AND A
LINGERING SHOWER OR TWO IS POSSIBLE CLOSER TO COAST EAST OF A
MYRTLE BEACH TO ELIZABETHTOWN LINE. ALL LAND AREAS SHOULD BE
PRECIPITATION FREE BY 15 UTC AND SKIES WILL BE CLEARING.
PRECIPITATION TOTALS ARE EXPECTED TO REMAIN LOW IN THIS EVENT.
AS THE COLD FRONT PUSHES OFFSHORE HIGH PRESSURE IS FORECAST BY BOTH
THE NAM AND GFS TO BUILD SOUTHWARD ALONG THE LEE OF THE APPALACHIAN
MOUNTAINS. AT THIS TIME NO PRECIPITATION IS EXPECTED BETWEEN
THURSDAY AFTERNOON AND FRIDAY NIGHT. NO SIGNIFICANT WEATHER IS
EXPECTED TO OCCUR IN THE LAST 36 HOURS OF THIS FORECAST PERIOD.
THE MAXIMUM TEMPERATURES ARE EXPECTED TO BE IN THE LOWER 70S WITH
THE WEST WINDS ON THURSDAY BEHIND THE FRONT. HIGHS ARE EXPECTED ONLY
TO REACH THE LOWER 60S WITH THE BEST COLD AIR ADVECTION NOT EXPECTED
INTO THE AREA UNTIL THURSDAY NIGHT. LOW TEMPERATURES ARE EXPECTED
TO FALL INTO THE LOWER 40S INLAND AND MID 40S ALONG THE IMMEDIATE
BEACHES.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
AS OF 3 PM WEDNESDAY...HIGH PRESSURE INIT OVER THE REGION SAT BUT
WILL BE PROGRESSING EAST ALLOWING FOR MOISTURE ADV AS THE DAY WEARS
ON. SAT NIGHT WARM FRONT SIG SEEN DEVEL IN PREV GUIDANCE NOW HARDER
TO MAKE OUT AND QUITE A BIT FARTHER NORTH. WILL CONTINUE LOW POPS
GRADED NW TO SE BUT LOWER. COLD FRONT SWEEPS THROUGH SUNDAY MIDDAY
OR EARLY PM. GOOD DYNAMICS NOT TOO FAR TO THE N SO ONCE AGAIN POPS
GRADED...THIS TIME HIGHEST N. UPPER TROUGH DEEPENS OFF NE COAST
MONDAY DRIVING SFC HIGH INTO THE SE ACCORD TO GFS WHILE OLDER ECMWF
IS FARTHER EAST AND QUICKER TO IMPLY WAA LOCALLY.SOME TEMP
RAMIFICATIONS THERE BUT ALSO A QUESTION REGARDING MOISTURE RECOVERY
AHEAD OF A WEAK SYSTEM FOR TUES. PREFER THE DRIER SOLNS AT THIS TIME
IF NOTHING ELSE GIVEN THE CURRENT DROUGHT.
&&
.AVIATION /00Z WEDNESDAY THROUGH MONDAY/...
AS OF 00Z...CLOUDS CLOSING IN ON THE TERMINALS AS PER THE SATELLITE
LOOP FROM THE WEST...EXPECT SOME MID LEVEL CLOUDS TO AFFECT THE
TERMINALS BETWEEN 00Z AND 02Z WITH LOW CHANCE FOR SOME STRATOCUMULUS
AS WELL. CLOUDS WILL LOWER AND THICKEN ACROSS THE TERMINALS DURING
THE OVERNIGHT PERIOD AS A COLD FRONT APPROACHES FROM THE WEST.
PRECIPITATION AHEAD AND ALONG THE FRONT WILL MOVE INTO THE REGION
TONIGHT AND OVERNIGHT. THE RAIN IS EXPECTED TO BE LIGHT MOST LIKELY
LESS THAN A TENTH OF AN INCH WITH A ISOLATED AREA OR TWO WITH SOME
HEAVIER SHOWERS...MAINLY INLAND. INLAND TERMINALS TO DROP FROM VFR
TO MVFR BETWEEN 04Z-08Z MAINLY IN CEILINGS WITH THE COASTAL
TERMINALS DROPPING INTO MVFR CATEGORY BETWEEN 07Z-11Z WITH CEILINGS
AS WELL. COULD SEE IFR/LIFR IN CEILINGS AND FOG IN TEMPO GROUPS
BETWEEN 12Z-15Z FROM INLAND TO COAST JUST AHEAD OF THE COLD FRONT.
SW WINDS WILL PREVAIL AHEAD OF THE FRONT ALL TERMINALS WITH WINDS
VEERING TO THE WEST AFTER 15Z AND THEN NW AFTER 18Z. FROPA IS
EXPECTED BY 14Z ACROSS FLO AND LBT AND AFTER 15Z FOR THE 3 COASTAL
TERMINALS. CEILINGS IMPROVE RAPIDLY AFTER FROPA BECOMING VFR ALL
TERMINALS.
EXTENDED OUTLOOK...LOW CONFIDENCE FOR IFR ASSOCIATED WITH RAIN LATE
SATURDAY INTO EARLY SUNDAY. OTHERWISE VFR.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 630 PM WEDNESDAY...A WEAK COLD FRONT WILL APPROACH FROM THE
WEST LATE TONIGHT...PROBABLY WAITING UNTIL AFTER DAYBREAK TO SCOOT
OUT ACROSS THE COASTAL WATERS. SOUTHWEST WINDS OUT IN ADVANCE OF THE
FRONT WILL CONTINUE OVERNIGHT WITH WIND SPEEDS GENERALLY 10-15 KT
OVER THE COASTAL WATERS FORECAST AREA. THE SINGLE EXCEPTION TO THIS
MIGHT BE NEAR FRYING PAN SHOALS WHERE WARM WATER TEMPERATURES (AND
GRADUALLY WARMER AIR TEMPERATURES) POKE INTO OUR FORECAST AREA AND
MAY ALLOW STRONGER WIND SPEEDS TO MIX DOWN FROM ALOFT. SOME 15-20 KT
WINDS ARE POSSIBLE HERE...GENERALLY OUT BEYOND 15 MILES FROM SHORE.
AN AREA OF LIGHT RAIN IN ADVANCE OF THE FRONT WILL MOVE OFFSHORE
AFTER MIDNIGHT.
SEA HEIGHTS REPORTED AT AREA BUOYS CONTINUE TO RUN BELOW MODEL
PROJECTIONS. WE HAVE MADE A FEW DOWNWARD TWEAKS TO SEAS THROUGH
DAYBREAK...KEEPING THE WORST CONDITIONS AROUND 4 FT IN THE FRYING
PAN SHOALS VICINITY OUT BEYOND 10 MILES FROM SHORE. ELSEWHERE AWAY
FROM THE IMMEDIATE COAST SEAS CURRENTLY AROUND 1 FOOT SHOULD BUILD
TO 2-3 FT OVERNIGHT.
SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
AS OF 3 PM WEDNESDAY...THE SHORT TERM FORECAST PERIOD WILL BEGIN
WITH A COLD FRONT SWEEPING ACROSS THE MARINE WATERS BY LATE MORNING
THE SOUTHWEST WINDS OF 15 KNOTS WILL VEER TO THE WEST BY AFTERNOON
AND WILL SLOWLY DECREASE WITH TIME. AS HIGH PRESSURE WEDGES IN TO
THE LEE OF THE APPALACHIAN MOUNTAINS THE WINDS WILL CONTINUE TO VEER
TO THE NORTH AND NORTHEAST THURSDAY NIGHT INTO FRIDAY. WIND SPEEDS
WILL RUN BETWEEN 10 AND 15 KNOTS DURING THE TIME FRAME. FINALLY BY
FRIDAY NIGHT THE WINDS WILL BE SHIFTING TO THE EAST AND WILL RUN
AROUND 10 KNOTS.
SEAS WILL START OUT AT 3 TO 4 FT AND WILL SLOWLY FALL TO 2 TO 3 FEET
BY THURSDAY NIGHT. SEAS WILL INCREASE TO 3 TO 4 FEET FRIDAY TO
FRIDAY NIGHT AS NORTHEAST FLOW INCREASES WITH THE COLD AIR DAMMING
TO THE WEST.
LONG TERM /SATURDAY THROUGH SUNDAY/...
AS OF 3 PM WEDNESDAY...LIGHT AND VEERING WINDS ON SAT AS SFC HIGH
PRESS SLIDES EAST ACRS THE MID-ATLANTIC JUST TO OUR N. WITH ONLY A
SMALL SWELL COMPONENT SEAS WILL BE PREDOMINANTLY WIND WAVES AND THUS
FAIRLY DIMINUTIVE...IN THE 2 TO 3 FT RANGE. A SHARPER VEER AND
PRONOUNCED INC IN SPEED THEN EXPECTED LATE SAT NIGHT AS HIGH MOVES
OFFSHORE AND COLD FRONT QUICKLY DRAWS NEAR...PINCHING THE GRAD
LOCALLY BETWEEN THE TWO. SEAS BUILD BUT THE SHORT DURATION OF HIGHER
WINDS AHEAD OF COLD FRONTAL PASSAGE APPEARS TO PRECLUDE ANY FLAGS AT
THIS TIME BUT CAUTIONARY HEADLINES APPEAR POSSIBLE. ANOTHER SHARP
VEER ASSOC WITH FROPA SUNDAY AFTERNOON TO CREATE A SHORT PERIOD OF
CONFUSION/CHOP TO WAVE FACES. UNCERTAINTY AT THIS TIME REGARDING HOW
LONG THE POST-FRONTAL PINCHED NE GRADIENT WINDS LAST BEFORE
SUBSIDING.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.
&&
$$
NEAR TERM...TRA
SHORT TERM...HAWKINS
LONG TERM...MBB
AVIATION...MAC
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
136 AM CST TUE JAN 31 2012
.DISCUSSION...
QUICK UPDATE FOR EARLY MORNING GRIDDS (06Z-12Z) TO MENTION MORE
ICE THAN SNOW AS RUC SHOWS WARM 850 MB TEMPS IN THE AREA TIL
12Z...
&&
.PREV DISCUSSION... /ISSUED 848 PM CST MON JAN 30 2012/
DISCUSSION...FORECAST CHALLENGE CONCERNS ONGOING HEADLINES
..ADDITIONAL PCPN AND TEMPERATURES. QUICK SHOT OF LIGHT FREEZING
RAIN JUST PRIOR TO DARK GREASED UP GFK ROADWAYS SO NEEDED TO DROP
ADVISORY SOUTH A SET OF COUNTIES DOWN STREAM IN NW MN. CURRENT
RADAR RETURNS ORIENTED ALONG AND AHEAD OF A WARM FRONT EXTENDING
FROM SURFACE LOW ALONG ND/CANADIAN BORDER NORTH OF MOT THROUGH GFK
TO FSE/BJI. THIS GENERALLY IN AREA OF CURRENT ADVISORY. SOUTH OF
WARM FRONT TEMPERATURES ABOVE FREEZING AND MINIMAL RADAR RETURNS
SO TRAVEL PROBLEMS NOT AS MUCH OF A CONCERN. QUESTION WILL BE IF
WARM FRONT LIFTS ANY FARTHER NORTH. TEMPERATURES CONTINUE SLOWLY
RISE VCNTY OF WARM FRONT WITH GFK APPROACHING 32. NOT MUCH OF A
SURFACE PRESSURE RISE/FALL COUPLET BUT EXPECT LOW TO RIDE ALONG
WARM FRONT SO DO NOT THINK WARMER TEMPERATURES WILL GET MUCH
FARTHER NORTH. WHILE RETURNS WEAKENING WILL CONTINUE WITH ADVISORY
AS SECONDARY BAND OF PCPN ASSOCIATED WITH APPROACHING COLD FRONT
COULD ALSO ARRIVE AS -RA AS COLUMN REMAINS WARM THROUGH 06Z.
COLUMN DOES COOL ALONG MN/CANADIAN BORDER AFT MIDNIGHT SO COULD
STILL SEE SOME MINOR SNOW ACCUMULATIONS ALONG WITH -ZR. THIS
COVERED WELL SO NOT MANY CHANGES NEEDED TO NEXT UPDATE.
AVIATION...CIGS/VSBY WILL CONTINUE IN VFR RANGE OVERNIGHT. COULD
SEE SOME MVFR VSBY LATER TONIGHT IN -SN ALONG INTERNATIONAL BORDER
AREA AS COLUMN COOLS. OTHERWISE ANY ADDITIONAL PCPN PRIOR TO EARLY
AM WILL BE LIKELY LIQUID MAKING FOR SLIPPERY CONDITIONS ACROSS
NORTHERN FORECAST AREA.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...WINTER WEATHER ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR
NDZ008-016.
MN...WINTER WEATHER ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR
MNZ001-004>009-013>017.
&&
$$
RIDDLE/VOELKER
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
807 PM CST WED FEB 1 2012
.DISCUSSION...
HAVE PARED BACK POPS FOR THE NIGHT EXCEPT OVER THE NORTH CLOSER TO
THE BOUNDARY. RUC AND 18Z NAM BOTH TRY TO DEVELOP A THIN BAND OF
PRECIP SOUTH OF THE BOUNDARY BENEATH THE JET STREAK MOVING INTO
LA. WILL CARRY 20S NORTH AFTER MIDNIGHT FOR THIS FOR NOW AND
20/30S OVER THE COASTAL WATERS.
FOG SHOULD RETURN TO THE AREA TONIGHT AND HAVE ISSUED A DENSE FOG
ADVISORY FOR SETX AND COASTAL WATERS. T/TD SPREADS 2-5 DEGREES WITH
DEWPOINTS IN THE 60S...70 SOUTHWEST. WITH THE WET GROUND...CALM
WINDS/LIGHT SOUTH WINDS/SKIES THAT HAVE AT LEAST PARTIAL CLEARED
EXPECT THE T/TD GAPS TO CLOSE QUICKLY WITH LARGE AREAS OF FOG
DEVELOPING AND BECOMING DENSE. A WARM DAY ON TAP TOMORROW WITH
LIGHT SOUTHEASTERLY FLOW SHOULD LEAD TO TEMPERATURES WARMING AFTER
8 AM AND THE FOG DISSIPATING. DO HAVE SOME CONCERNS THAT WITH THE
MORE STABLE AIRMASS OVER THE COASTAL AREAS THE DENSE FOG MAY LAST
BEYOND 9 AM.
45
&&
.PREV DISCUSSION... /ISSUED 528 PM CST WED FEB 1 2012/
AVIATION...
MOST PCPN HAS MOVED SOUTH AND EAST OF THE AREA. A FEW LIGHT RW
MIGHT IMPACT KGLS BUT ALL OTHER TAF SITES SHOULD BE FREE OF PCPN.
MOSTLY VFR CONDITIONS WILL PREVAIL EARLY TONIGHT. ABUNDANT LOW
LEVEL MOISTURE ALONG WITH GROUND WATER WILL LEAD TO DEVELOPMENT OF
LOW CLOUDS AND FOG OVERNIGHT. EXPECT DENSE FOG TO DEVELOP AND
IMPACT ALL TAF SITES MAINLY AFTER 06Z AND IMPROVING AFTER 15Z.
CONDITIONS WILL IMPROVE TO VFR AFTER 18Z. EXPECT ANOTHER ROUND OF
DENSE FOG THURSDAY NIGHT BUT WILL LIKELY BEGIN EARLIER IN THE EVENING.
PREV DISCUSSION... /ISSUED 332 PM CST WED FEB 1 2012/
DISCUSSION...
HOUSTON AIRPORTS CURRENTLY SITTING 2-3 DEGREES BELOW RECORD HIGHS
(82-IAH, 81-HOU) WITH A LIGHT WEST WINDS AND MSUNNY SKIES. PRECIP
HAS MOSTLY CLEARED THE COAST BUT CANNOT RULE OUT A FEW MORE TO POP
UP INLAND CONSIDERING THE WARMTH. STORMS HAVE TEMPORARILY CLEARED
THE SEA FOG OUT OF THE NEARSHORE WATERS BUT DO EXPECT IT TO ROLL
BACK IN OVERNIGHT. ALSO EXPECT SOME FOG TO REDEVELOP INLAND ESP
AFTER MIDNIGHT AHEAD OF A WEAK FRONTAL BOUNDARY THAT WILL EDGE
INTO NRN PARTS OF THE CWA AND STALL.
MOISTURE POOLING SOUTH OF THE BOUNDARY...DAYTIME HEATING AND WEAK
IMPULSES IN THE SW FLOW ALOFT SHOULD PROVIDE ADDITIONAL SCT
SHRA/TSTM ACTIVITY ON THURS. WENT ABOVE GUIDANCE SUGGESTIONS ON
POPS...AND QUITE POSSIBLY NOT HIGH ENOUGH. EXPECT THE STATIONARY
FRONTAL BOUNDARY TO MOVE BACK NORTH AS A WARM FRONT THRU THE DAY
AS LOW PRES DEEPENS TO THE WEST. EXPECT PRECIP TO TAPER OFF FROM
SOUTH TO NORTH THRU THE LATE AFTN HOURS.
REALLY NOT A LOT OF CHANGES FRI - SW FLOW ALOFT...HEATING AND
MOISTURE SHOULD LEAD TO SCT PRECIP. WORTH NOTING THE GOOD DIFFLUENCE
ALOFT DUE TO JET STRUCTURE AND SOMETHING TO KEEP AN EYE ON.
MODELS IN SOMEWHAT BETTER AGREEMENT REGARDING THE TIMING OF THE
NEXT FRONT. LOOKING LIKE IT WILL MOVE INTO SE TX LATE FRI NIGHT
AND OFF THE COAST AROUND NOON SATURDAY. ANTICIPATE A LINE OF
SHRA/TSTMS AHEAD/ALONG THE BOUNDARY.
NOT EXPECTING THINGS TO CLEAR OUT IN THE WAKE OF THE FRONT AS WE
WILL CONTINUE TO REMAIN IN A SW FLOW ALOFT. A SERIES IMPULSES
EMBEDDED IN THIS FLOW ARE FCST TO CONTINUE MOVING OVERHEAD INTO
EARLY NEXT WEEK PROVIDING A CONTINUED CHANCE OF PRECIP. TIMING OF
THESE FEATURES THIS FAR OUT IS NOT MUCH MORE THAN A GUESS...BUT
GFS/ECMWF ARE HINTING AT ANOTHER WET DAY ON SUNDAY. 47
MARINE...
MAIN SHORT TERM FCST ISSUE WILL BE SEA FOG. STORMS HAVE PUSHED IT
OFFSHORE BUT EXPECT IT TO RETURN OVERNIGHT AND PROBABLY CONTINUE
INTO SATURDAY (WITH SHORT TERM VISBY IMPROVEMENTS EACH AFTERNOON).
WINDS/SEAS SHOULD GRADUALLY INCREASE LATE THURS AND FRI AS PRES
GRADIENT TIGHTENS AND ONSHORE FLOW INCREASES. NEXT FRONT FCST TO
PUSH OFF THE COAST EARLY SAT AFTN. EXPECT A LINE OF SHRA/TSTMS
AHEAD OF THE FRONT. 47
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 63 78 63 77 60 / 20 40 20 50 60
HOUSTON (IAH) 64 78 63 77 65 / 10 40 20 50 60
GALVESTON (GLS) 65 72 63 71 63 / 20 30 20 40 40
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...DENSE FOG ADVISORY UNTIL 9 AM CST THURSDAY FOR THE FOLLOWING
ZONES: AUSTIN...BRAZORIA...BRAZOS...BURLESON...CHAMBERS...
COLORADO...FORT BEND...GALVESTON...GRIMES...HARRIS...
HOUSTON...JACKSON...LIBERTY...MADISON...MATAGORDA...
MONTGOMERY...POLK...SAN JACINTO...TRINITY...WALKER...
WALLER...WASHINGTON...WHARTON.
GM...DENSE FOG ADVISORY UNTIL 9 AM CST THURSDAY FOR THE FOLLOWING
ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS FROM FREEPORT
TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM
FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS
FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...45
FOR FREQUENTLY ASKED QUESTIONS ABOUT THE AREA FORECAST DISCUSSION VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY/GENERAL/AFD_FAQS.PHP (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
729 PM CST WED FEB 1 2012
.SHORT TERM...
729 PM CST WED FEB 1 2012
LATEST RUC FORECAST SOUNDINGS AND SURFACE REPORTS SHOWING DENSE
FOG TO PERSIST THROUGH MUCH OF THE NIGHT WEST OF THE MISSISSIPPI
RIVER. CALLS TO AREA COUNTIES SHOWING VISIBILITIES UNDER A QUARTER
OF A MILE AND BUFKIT SOUNDINGS SHOW LOW LEVEL FLOW WEAK THROUGH
MUCH OF THE NIGHT. IF THE DRIER AIR ASSOCIATED WITH THE WEAK SHORTWAVE
MAKES IT...IT WILL BE AFTER MIDNIGHT. IF THIS OCCUR ADVISORY MAY
BE CANCELED EARLY. OTHERWISE WILL RUN IT INTO THURSDAY MORNING.
UPDATED PRODUCTS WILL BE OUT SHORTLY.
.LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY
311 PM CST WED FEB 1 2012
MAIN FORECAST CONCERNS ARE PRECIPITATION CHANCES SATURDAY NIGHT
INTO SUNDAY. THE 01.12Z GFS/ECMWF/GEM CONTINUE TO BE
DIFFERENT IN TIMING AND PLACEMENT OF UPPER LEVEL LOW SLOWLY LIFTING
NORTHEASTWARD INTO THE UPPER GREAT LAKES AND UPPER MIDWEST
SATURDAY NIGHT INTO SUNDAY NIGHT. THE MODELS DO SUGGEST THE
PRECIPITATION IN ASSOCIATION WITH THE UPPER LEVEL LOW WILL BE
CONFINED MAINLY OVER THE SOUTHERN HALF OF THE FORECAST AREA SATURDAY
NIGHT INTO SUNDAY. AS FAR AS PRECIPITATION TYPES...THE 01.12Z GFS
BUFKIT SOUNDINGS DO INDICATE SNOW MAINLY AT NIGHT AND A MIXTURE OF
RAIN AND SNOW DURING THE DAY. AFTER 12Z MONDAY...THE DETERMINISTIC
GEM/GFS/ECMWF ARE IN MUCH BETTER AGREEMENT WITH BUILDING SURFACE
RIDGE INTO THE NORTHERN PLAINS AND THE UPPER MIDWEST. DRY WEATHER
CONDITIONS AND SEASONABLE TEMPERATURES CAN BE EXPECTED ACROSS THE
FORECAST AREA TUESDAY INTO MIDDLE OF NEXT WEEK.
&&
.AVIATION...TONIGHT AND THURSDAY
534 PM CST WED FEB 1 2012
CEILINGS AND VISIBILITIES REMAIN THE MAIN CONCERNS. LIFR
CONDITIONS REMAIN IN PLACE AT KRST LATE THIS AFTERNOON...WHILE
LOWER MVFR CEILINGS RESIDE AT KLSE. WEAK 925MB TROUGH IS LOCATED
OVER SOUTHWEST MINNESOTA...WHERE SURFACE WINDS HAVE SWITCHED TO
THE WEST WHERE VISIBILITIES ARE P6SM. 01.21Z RUC MOVES THIS TROUGH
ACROSS THE TAF SITES BETWEEN 03Z-06Z THIS EVENING...WITH WINDS
BECOMING MORE SOUTHWESTERLY. DRIER AIR LOOKS TO ADVECT INTO THE
AREA AT THIS TIME. THE QUESTION IS WILL THIS BE ENOUGH DRY AIR TO
RAISE THE VISIBILITIES. MODEL TRENDS WOULD SUGGEST YES AND THUS
WENT VISIBILITIES RISING AFTER 03Z AT KRST INTO THE MVFR
CATEGORY. AS FOR KLSE...VISIBILITIES LIKELY TO LOWER PERHAPS INTO
THE 2-3SM RANGE LATER THIS EVENING WITH CEILINGS REMAINING AROUND
010KFT. NOT AS CONFIDENCE WITH CEILINGS RISING UNTIL AFTER 06Z
THOUGH. VFR CONDITIONS THEN LOOK TO SET UP AFTER 15Z AT BOTH TAF
SITES AND CONTINUE THROUGH 00Z FRIDAY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
722 PM CST WED FEB 1 2012
WI...NONE.
MN...DENSE FOG ADVISORY UNTIL 10 AM CST THURSDAY FOR MNZ079-086>088-
094>096.
IA...DENSE FOG ADVISORY UNTIL 10 AM CST THURSDAY FOR IAZ008>011-018-
019-029-030.
&&
$$
SHORT TERM...RABERDING
LONG TERM....DTJ
AVIATION...RABERDING
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
558 PM CST WED FEB 1 2012
UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND THURSDAY.
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW LOW PRESSURE
OVER SOUTHERN QUEBEC AND A LARGE HIGH PRESSURE SYSTEM STRETCHING
FROM THE SOUTHERN PLAINS INTO THE WESTERN GREAT LAKES. WIDESPREAD
1-2KFT STRATUS EXISTS ACROSS MUCH OF THE WESTERN AND CENTRAL GREAT
LAKES EARLY THIS AFTERNOON...THOUGH EVEN LOWER CEILINGS AND FOG
EXIST BACK TO THE NORTHERN MISSISSIPPI VALLEY. MEANWHILE FARTHER
UPSTREAM...A WEAK SHORTWAVE TROUGH IS DIVING SE OVER THE ND/MANITOBA
BORDER. NOT MUCH PRECIP ACTIVITY WITH THIS WAVE...BUT AS IT TRACKS
TOWARDS NORTHERN WISCONSIN TONIGHT...LIGHT SNOW CHANCES AS WELL AS
CLOUD COVER ARE THE MAIN FORECAST CONCERNS.
TONIGHT...BROAD HIGH PRESSURE OVER THE PLAINS WILL DRIFT
EAST OVER THE WESTERN GREAT LAKES TONIGHT...WHILE A WEAK SHEARED
SHORTWAVE TROUGH DIVES SOUTH OVER NORTHERN WISCONSIN. FORCING IS
PRETTY WEAK WITH THIS WAVE AND MID-LEVELS STRUGGLE TO SATURATE.
STILL THOUGH...DEWPOINT DEPRESSIONS ARE LOW ENOUGH TO WARRANT AT
LEAST FLURRIES OVER NORTHERN WISCONSIN AFTER MIDNIGHT...AND WILL
KEEP A TENTH OR TWO OF ACCUMS ALONG THE U.P. BORDER.
OTHERWISE...THE LIGHT WIND REGIME AND AMPLE MOISTURE STUCK BENEATH
THE BL INVERSION ARE SUPPORTIVE OF THE LOW STRATUS STICKING AROUND
ALL NIGHT LONG. IF HOLES IN THE CLOUDS OCCUR...THEN FOG WOULD
DEVELOP. SO WENT PESSIMISTIC WITH CLOUD COVER FOR THIS FORECAST.
LOWS WILL ONLY FALL A FEW DEGREES WITH THE CLOUD COVER.
THURSDAY...THE SHORTWAVE TROUGH WILL EXIT NE WISCONSIN DURING THE
MORNING AND WILL LEAVE A CHANCE OF FLURRIES IN THE FORECAST.
OTHERWISE...PACIFIC HIGH PRESSURE WILL STICK AROUND THE REGION.
925MB TEMPS DO WARM A FEW DEGREES OVER CENTRAL AND EAST-CENTRAL
WISCONSIN IN THE AFTERNOON. SO WILL SHOW WIDESPREAD LOW STRATUS IN
THE MORNING ERODING THERE FIRST TOMORROW AFTERNOON. TEMPS REMAIN
DIFFICULT PENDING POTENTIAL SUNSHINE AND WILL GO UPPER 30S NORTH TO
MIDDLE 40S SOUTH.
.LONG TERM...THU NGT THRU NXT WED. SPLIT FLOW REMAINS THE RULE
ACROSS THE CONUS DURING THE EXTENDED PART OF THE FCST. ONLY REAL
PBLM TO BE THE EVENTUAL MOVEMENT OF A MODEST CLOSED UPR LOW DURING
THE SUNDAY/MON TIME PERIOD. MDLS HAVE DRIFTED THIS SYSTEM FARTHER
NORTH (ESP THE ECMWF/UKMET) WHICH WOULD NOW BRING A CHC OF PCPN TO
PARTS OF THE FCST AREA. ONCE THIS SYSTEM DEPARTS..A BRIEF SHOT OF
COOLER AIR OVERSPREADS THE GREAT LKS...BUT ONLY APRS TO BE A BLIP
ON THIS WARM WINTER AS TEMPS LOOK TO WARM AGAIN LATER NXT WEEK.
HI PRES TO STRETCH FROM SRN SASKATCHEWAN EWD INTO WRN ONTARIO...
COUPLED WITH ANOTHER HI PRES OVER WRN PA...WL KEEP THE TRANQUIL
WEATHER GOING THU NGT. THERE IS A WEAK THERMAL TROF AT THE SFC
OVER NRN SECTIONS OF THE GREAT LKS WHICH WOULD KEEP MORE CLOUDS
OVER NRN WI THAN CNTRL/E-CNTRL WI. HOWEVER...TIME SECTIONS/FCST
SNDNGS INDICATE THAT MSTR JUST ABV THE SFC MAY BE TRAPPED BLO AN
INVERSION...THUS MOSTLY CLOUDY SKIES EXPECTED THROUGHOUT ALL OF NE
WI. MIN TEMPS WL BE HELD UP BY THESE CLOUDS AND FAVOR THE WARMER
SIDE OF GUIDANCE.
ATTENTION TURNS TOWARD THE CNTRL CONUS AS A CLOSED UPR LOW EXITS
THE ROCKIES AND MOVES INTO THE CNTRL PLAINS ON FRI. INCREASING
SOUTHERLY WINDS ARE EXPECTED TO BEGIN DRAWING GULF MSTR NWD THRU
THE OZARKS INTO THE MID-MS VALLEY WITH SHWRS/TSTMS BREAKING OUT.
MEANWHILE...HI PRES TO EXTEND FROM THE NRN PLAINS EAST THRU NRN
SECTIONS OF THE GREAT LKS AND PROVIDE A DRY EASTERLY FLOW INTO WI.
MAY STILL BE DEALING WITH LINGERING LOW CLOUDS WHICH WOULD PUT A
CRIMP ON MAX TEMPS. FOR NOW...HAVE TEMPERED READINGS DOWN A DEGREE
OR TWO FROM THE PREV FCST...BUT STILL WELL-ABOVE NORMAL.
AS THE UPR LOW SLOWLY TRUDGES ACROSS THE CNTRL PLAINS FRI NGT...
GULF MSTR WL MAKE A SURGE NORTH TOWARD THE GREAT LKS THANKS TO A
50 KT SW LOW-LVL JET. THE AREA OF HI PRES REMAINS ANCHORED OVER
NRN SECTIONS OF THE GREAT LKS...THUS SETTING UP A BATTLE BETWEEN
THE ENTRENCHED DRY AIR AND INCOMING MSTR. HAVE KEPT NRN WI PARTLY
CLOUDY WITH PARTLY TO MOSTLY CLOUDY SKIES FOR CNTRL/E-CNTRL WI.
THIS SET-UP WOULD PROVIDE FOR A WIDE RANGE IN TEMPS WITH THE NORTH
FALLING INTO THE LOWER TO MIDDLE TEENS...WHILE THE LAKESHORE AREAS
ONLY DIP INTO THE MIDDLE TO UPPER 20S. THE CLOSED UPR LOW IS FCST
TO MOVE E-NE INTO THE MIDWEST (VCNTY SRN IA) ON SAT. SOUTHERLY
WINDS OVERRUNNING A WRMFNT STRETCHED FROM THE MIDWEST E-SE INTO
THE OHIO RIVER VALLEY...WL BEGIN TO SPREAD CLOUDS NWD INTO WI BY
SAT AFTERNOON. STILL EXPECT A NICE DAY ACROSS NE WI WITH MAX TEMPS
A GOOD 10 TO 15 DEGS ABV NORMAL.
MDL INCONSISTENTCY PERSISTS WITH THE HANDLING OF THE SYSTEM HEADED
INTO SUNDAY AND THIS RESULTS IN POTENTIALLY SIGNIFICANT SENSIBLE
WEATHER DIFFERENCES FOR THE FCST AREA. IF THIS SYSTEM TRACKS NE...
IT WOULD BRING A LGT SNOW OR SNOW/RAIN THREAT TO MUCH OF NE WI. AN
EWD TRACK WOULD ONLY BRUSH CNTRL/E-CNTRL WI WITH PERHAPS A DUSTING
TO A COUPLE TENTHS OF AN INCH OF SNOW. PREFER TO TAKE A CAUTIOUS
APPROACH HERE UNTIL THE MDLS SETTLE DOWN AND WL ONLY MENTION A SML
POP GENERALLY ALONG/SOUTH OF A MFI-SUE LINE. SML POPS WOULD THEN
BE NEEDED INTO SUNDAY NGT AS THE SYSTEM EITHER MOVES INTO NRN OR
SRN SECTIONS OF THE GREAT LKS RGN. SOME EVIDENCE OF IMPROVING
CONDITIONS FOR MON AS THE SYSTEM PULLS AWAY WITH A WEAK UPR RDG
SLIDING INTO WI. MAX TEMPS TO REMAIN WELL ABV NORMAL WITH PLENTY
OF MIDDLE TO UPPER 30S EXPECTED.
A SECONDARY CDFNT DROPS SWD THRU WI MON NGT...BUT MDLS VARY AS TO
THE EXTENT OF THE COLD AIR TO FILTER INTO THE RGN. THE 12Z ECMWF
HAS BACKED OFF QUITE A BIT WITH 8H TEMPS FALLING INTO THE LOWER TO
MIDDLE TEENS BLO ZERO (COMPARED TO -20C ON ITS PREV RUN). THE GFS
IS COMPARABLE WITH ITS PREV RUN WITH 8H TEMPS AROUND -10C. BASED
ON THE SPLIT FLOW PATN...WL LEAN TOWARD THE GFS SOLN WHICH KEEPS
TEMPS ABV NORMAL THRU TUE. WL NEED TO WATCH FOR POTENTIAL OF LK
EFFECT SNOW SHOWERS FOR VILAS CNTY MON NGT INTO TUE AS TRAJS BECOME
FAVORABLE. HAVE ADDED A SML CHC POP THERE FOR NOW. OTHERWISE...HI
PRES TO START BUILDING EWD FROM THE NRN PLAINS AND KEEP THE REST
OF NE WI ON THE QUIET SIDE. THIS BROAD/STRONG AREA OF HI PRES
SETTLES SOUTH AND EAST ACROSS THE CNTRL CONUS BY NXT WED AND WL
CONT TO PROVIDE DRY CONDITIONS TO NE WI. ANY LK EFFECT ACROSS
VILAS CNTY WL CEASE AS DRIER AIR ADVECTS INTO THE RGN. EVEN THO
TEMPS MAY COOL A BIT...ANTICIPATE READINGS TO REMAIN ABOUT 5 DEGS
ABV NORMAL FOR EARLY FEB.
&&
.AVIATION...
LARGE AREA OF CLEAR SKIES OPENED UP OVER NORTHEAST WI THIS
AFTN...THOUGH EXPECTED TO BE OF SHORT DURATION. WEST WINDS AHEAD
OF SHORT WAVE OVER WESTERN MN TO HELP ADVECT LOW CLOUDS AND FOG
OVER MN/IA INTO WI. HIGH PRESSURE AT THE SURFACE WIILL ALSO BUILD INTO
THE REGION TONIGHT...LIGHT WINDS AND HIGH DEWPOINTS WOULD PROMOTE
FOG FORMATION. THUS WILL STAY WITH PESSIMISTIC IFR/MVFR CIGS
THROUGH THU AFTERNOON. WEAK UPPER LEVEL DISTURBANCE MAY BRING A
CHANCE OF FLURRIES LATE TONIGHT INTO THU MORNING...THOUGH
CONFIDENCE IS LOW DUE TO MOISTURE CONCERNS.
TE
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
535 PM CST WED FEB 1 2012
.SHORT TERM...TONIGHT THROUGH SATURDAY
311 PM CST WED FEB 1 2012
MAIN FORECAST CONCERNS ARE CLOUDS AND FOG TRENDS THIS
EVENING/TONIGHT...THEN PRECIPITATION CHANCES AND TYPES FRIDAY NIGHT
INTO SATURDAY.
LATEST VISIBLE SATELLITE IMAGERY SHOWING LOW STRATUS/DENSE FOG
BEGINNING TO DIMINISH ACROSS THE UPPER GREAT LAKES REGION. LATEST
20Z METARS ARE INDICATING VISIBILITIES IMPROVING OVER PORTIONS OF
SOUTHEAST MINNESOTA AND NORTHEAST IOWA.
THE 01.12Z DETERMINISTIC GFS/NAM ARE IN DECENT AGREEMENT WITH
OVERALL UPPER LEVEL AND SURFACE FEATURES THROUGH 00Z SATURDAY.
THEN...BEGIN TO DIVERGE SLIGHTLY ON TIMING AND PLACEMENT OF UPPER
LEVEL/SURFACE LOW INTO THE GREAT LAKES REGION AFTER 00Z SATURDAY.
ANOTHER SIGNIFICANT DIFFERENCE OCCURS AFTER 00Z SATURDAY...AS THE
01.12Z NAM IS COOLER ON NORTHERN PERIPHERY OF UPPER
LEVEL/SURFACE LOW PER BUFKIT SOUNDINGS THAN THE GFS. THIS WILL HAVE
IMPACTS ON PRECIPITATION TYPE FRIDAY NIGHT AND INTO SATURDAY.
TONIGHT...WITH LOW STRATUS AND DENSE FOG DIMINISHING ACROSS
FORECAST AREA...WILL CANCEL DENSE FOG ADVISORY ACROSS PORTIONS OF
SOUTHEAST MINNESOTA AND NORTHEAST IOWA. THE LATEST 01.12Z GFS/NAM
AND 01.15Z RUC INDICATE INVERSION TO SET UP OVER THE FORECAST AREA
THIS EVENING. WITH ABUNDANT BOUNDARY LAYER MOISTURE...DUE TO CLOUD
COVER DURING THE DAY. HAVE INTRODUCED AREAS OF FOG TONIGHT INTO
THURSDAY MORNING ACROSS FORECAST AREA.
ALL THE 01.12Z DETERMINISTIC MODELS ARE CARVING TROUGH AND CUTTING
OFF UPPER LEVEL LOW OVER THE WESTERN UNITED STATES THURSDAY NIGHT
INTO FRIDAY...THEN SLOWLY LIFT UPPER LEVEL LOW INTO THE UPPER
MIDWEST AND GREAT LAKES REGION FRIDAY NIGHT INTO SATURDAY. THE
MODELS DO INDICATE DECENT ISENTROPIC LIFT AT 290K SURFACE AND DEEP QG
FORCING OVER PORTIONS OF NORTHEAST IOWA AND SOUTHWEST WISCONSIN.
THIS WILL SPREAD A BAND OF PRECIPITATION INTO THIS AREA AFTER 06Z
SATURDAY. THE LATEST 01.12Z DETERMINISTIC GFS/NAM DO INDICATE
TEMPERATURES BELOW OR NEAR FREEZING THROUGH THE ATMOSPHERE
COLUMN FRIDAY NIGHT INTO SATURDAY PER BUFKIT SOUNDINGS. HOWEVER...THE
LATEST 01.12Z ECMWF IS MUCH FARTHER WEST WITH THE 850MB LOW AND
ADVECTS SLIGHTLY WARMER AIR NORTHWARD INTO THE REGION. UNCERTAINTIES
EXIST AS TOO HOW MUCH WARM AIR ADVECTS NORTHWARD INTO THE REGION
FRIDAY NIGHT INTO SATURDAY. FOR NOW...HAVE KEPT MAINLY ALL SNOW FROM
06Z THROUGH 18Z SATURDAY...AND A RAIN/SNOW MIX AFTER 18Z SATURDAY
ACROSS MUCH OF THE SOUTHERN HALF OF FORECAST AREA. SIGNIFICANT
SNOW ACCUMULATION WILL DEPEND ON THE EXACT TRACK OF THE UPPER
LEVEL/SURFACE LOW AND THE TEMPERATURES THROUGH THE ATMOSPHERE COLUMN
FRIDAY NIGHT INTO SATURDAY.
.LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY
311 PM CST WED FEB 1 2012
MAIN FORECAST CONCERNS ARE PRECIPITATION CHANCES SATURDAY NIGHT
INTO SUNDAY. THE 01.12Z GFS/ECMWF/GEM CONTINUE TO BE
DIFFERENT IN TIMING AND PLACEMENT OF UPPER LEVEL LOW SLOWLY LIFTING
NORTHEASTWARD INTO THE UPPER GREAT LAKES AND UPPER MIDWEST
SATURDAY NIGHT INTO SUNDAY NIGHT. THE MODELS DO SUGGEST THE
PRECIPITATION IN ASSOCIATION WITH THE UPPER LEVEL LOW WILL BE
CONFINED MAINLY OVER THE SOUTHERN HALF OF THE FORECAST AREA SATURDAY
NIGHT INTO SUNDAY. AS FAR AS PRECIPITATION TYPES...THE 01.12Z GFS
BUFKIT SOUNDINGS DO INDICATE SNOW MAINLY AT NIGHT AND A MIXTURE OF
RAIN AND SNOW DURING THE DAY. AFTER 12Z MONDAY...THE DETERMINISTIC
GEM/GFS/ECMWF ARE IN MUCH BETTER AGREEMENT WITH BUILDING SURFACE
RIDGE INTO THE NORTHERN PLAINS AND THE UPPER MIDWEST. DRY WEATHER
CONDITIONS AND SEASONABLE TEMPERATURES CAN BE EXPECTED ACROSS THE
FORECAST AREA TUESDAY INTO MIDDLE OF NEXT WEEK.
&&
.AVIATION...TONIGHT AND THURSDAY
534 PM CST WED FEB 1 2012
CEILINGS AND VISIBILITIES REMAIN THE MAIN CONCERNS. LIFR
CONDITIONS REMAIN IN PLACE AT KRST LATE THIS AFTERNOON...WHILE
LOWER MVFR CEILINGS RESIDE AT KLSE. WEAK 925MB TROUGH IS LOCATED
OVER SOUTHWEST MINNESOTA...WHERE SURFACE WINDS HAVE SWITCHED TO
THE WEST WHERE VISIBILITIES ARE P6SM. 01.21Z RUC MOVES THIS TROUGH
ACROSS THE TAF SITES BETWEEN 03Z-06Z THIS EVENING...WITH WINDS
BECOMING MORE SOUTHWESTERLY. DRIER AIR LOOKS TO ADVECT INTO THE
AREA AT THIS TIME. THE QUESTION IS WILL THIS BE ENOUGH DRY AIR TO
RAISE THE VISIBILITIES. MODEL TRENDS WOULD SUGGEST YES AND THUS
WENT VISIBILITIES RISING AFTER 03Z AT KRST INTO THE MVFR
CATEGORY. AS FOR KLSE...VISIBILITIES LIKELY TO LOWER PERHAPS INTO
THE 2-3SM RANGE LATER THIS EVENING WITH CEILINGS REMAINING AROUND
010KFT. NOT AS CONFIDENCE WITH CEILINGS RISING UNTIL AFTER 06Z
THOUGH. VFR CONDITIONS THEN LOOK TO SET UP AFTER 15Z AT BOTH TAF
SITES AND CONTINUE THROUGH 00Z FRIDAY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
311 PM CST WED FEB 1 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...DTJ
LONG TERM....DTJ
AVIATION...RABERDING
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
237 PM CST TUE JAN 31 2012
.SHORT TERM...TONIGHT THROUGH WEDNESDAY.
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A MOISTURE
STARVED LOW PRESSURE SYSTEM MOVING OVER THE CENTRAL UPPER PENINSULA
EARLY THIS AFTERNOON...AND ITS ASSOCIATED COOL FRONT PUSHING ACROSS
CENTRAL WISCONSIN. THE COLDER AIR IS LAGGING BEHIND THE FRONT AND
CAN BE MARKED BY THE LEADING EDGE OF A LOW STRATUS DECK THAT IS
SHIFTING SE OVER MINNESOTA AND ALMOST TO THE WI BORDER. DESPITE THE
SHALLOW NATURE OF THE LOW MOISTURE ON 12Z RAOBS...MIXING HAS NOT
DETERRED ITS PROGRESS SO FAR TODAY. WILL MAKE SOME LAST MINUTE
ADJUSTMENTS TO SPEED UP ITS FORWARD MOTION IF THIS CONTINUES TO BE
THE CASE. AS THESE CLOUDS ADVANCE TOWARDS NORTHERN
WISCONSIN...CLOUDS AND TEMPS ARE THE MAIN FORECAST CONCERNS.
TONIGHT...LOW PRESSURE WILL CONTINUE TO TRACK TO THE EAST OVER THE
EASTERN UPPER PENINSULA INTO SOUTHEAST ONTARIO. MID AND HIGH CLOUDS
WILL DEPART THIS EVENING WITH THE ELONGATED SHORTWAVE TROUGH...BUT
PLENTY OF LOW CLOUDS UPSTREAM WILL SHIFT SE WITHIN A COOLER AIRMASS
WRAPPING AROUND THE LOW AND INTO THE NORTHERN HALF OF THE STATE.
ALTHOUGH THE MOISTURE IS SHALLOW AND SOME EROSION IS EXPECTED...THE
COOLER AIRMASS WILL PROMOTE ITS ADVANCEMENT ACROSS NORTH-CENTRAL AND
CENTRAL WISCONSIN TONIGHT. THINK DOWNSLOPING SHOULD PREVENT THE
STRATUS FROM MAKING IT INTO THE FOX VALLEY AND NORTHEAST
WISCONSIN...SO HAVE KEPT PARTLY CLOUDY WORDING THERE. NO REAL
CHANCE OF DECOUPLING TONIGHT...SO LOWS WILL BE MILD AND RANGE FROM
THE LOWER 20S NORTH TO AROUND 30 SOUTHEAST.
WEDNESDAY...STRATUS WILL LIKELY HANG AROUND FOR MUCH OF THE MORNING
OVER NORTHERN WISCONSIN THOUGH SOME EROSION IS LIKELY OVER CENTRAL
WISCONSIN WITH DAYTIME HEATING. THE COOLER AIRMASS WILL CONTINUE TO
MODERATE THROUGH THE AFTERNOON SO EXPECTING CLOUDS TO RETREAT TO THE
NORTH OR NORTHEAST THROUGH THE DAY. ALSO IN THE AFTERNOON...THE
NEXT SHORTWAVE TROUGH WILL MOVE INTO WESTERN WISCONSIN. MID-LEVELS
HAVE A DRY WEDGE SO NO REAL THREAT OF PRECIP. HIGHS WILL BE COOLER
THAN TODAY...AND WILL GO WITH MID TO UPPER 30S.
.LONG TERM...WEDNESDAY NIGHT THROUGH NEXT TUESDAY. SOUNDS LIKE A
BROKEN RECORD...BUT MORE MILD AND DRY WEATHER EXPECTED FOR THE
NEXT WEEK OR SO. THE SPLIT FLOW PATTER WILL CONTINUE WITH WEAK
SHORTWAVE TROUGHS MOVING BY TO THE NORTH THROUGH WITH LITTLE
MOISTURE WHILE MORE SIGNIFICANT SYSTEMS IN THE SOUTHERN STREAM STAY
TO OUR SOUTH. ANY PHASING THAT TAKES PLACE IS WELL TO OUR EAST.
THE BEST CHANCE OF ANY PRECIPITATION LOOKS TO BE SUNDAY OR SUNDAY
NIGHT AS SYSTEM IN THE SOUTHERN STREAM PASSES BY TO THE SOUTH. IT
MAY CLIP CENTRAL AND NORTHERN WISCONSIN WITH SOME LIGHT SNOW OR
RAIN BUT THAT/S ABOUT IT.
&&
.AVIATION...
LOW PRESSURE WILL BE PASSING OVER THE U.P. THIS AFTERNOON WITH ONLY
WIDESPREAD MID AND HIGH CLOUDS THAT WILL DEPART LATE THIS AFTERNOON
INTO THIS EVENING. BIGGER CONCERN FOR THE TAF DEPARTMENT IS THE
LARGE AREA OF IFR CIGS BEHIND THE LOW OVER THE DAKOTAS AND
MINNESOTA. COOLER AIR BEHIND THE LOW WILL FILTER ACROSS NORTHERN
WISCONSIN TONIGHT WHICH WILL PROMOTE THE ADVANCEMENT OF THIS IFR
STRATUS DECK. SOME MIXING WILL LIKELY CAUSE THE STRATUS TO BREAK UP
THIS AFTERNOON...WHICH WILL ONLY SERVE TO DELAY ITS ARRIVAL. DO NOT
SEE MUCH TO STOP IT GETTING INTO RHI THIS EVENING. CENTRAL
WISCONSIN IS ON THE EDGE OF THIS COOLER AIRMASS SO BELIEVE THE
STRATUS WILL MAKE A RUN AT AUW/CWA. THREW A TEMPO IN THE TAFS FOR
TONIGHT TO ACCOUNT FOR THIS. AM COUNTING ON DOWNSLOPING TO KEEP THE
STRATUS OUT OF THE FOX VALLEY AND NE WISCONSIN. STRATUS SHOULD
RETREAT TOMORROW MORNING WITH DAYTIME HEATING BUT SHOULD HANG AROUND
NORTHERN WISCONSIN THROUGH THE REST OF THE TAF PERIOD.
MPC
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
MPC/RDM
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1057 PM CST MON JAN 30 2012
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.SHORT TERM UPDATE...
SHORTWAVE DISTURBANCE MOVING ACROSS THE EASTERN DAKOTAS INTO
CENTRAL MINNESOTA GENERATING SOME SCATTERED VERY LIGHT MIX WEST
OF DLH THIS EVENING. LATEST MODEL GUIDANCE STILL INSISTS THAT BULK
OF MEASURABLE LIGHT PRECIPITATION WILL GENERALLY REMAIN NORTH OF
THE WISCONSIN MICHIGAN BORDER OVERNIGHT. GRB...MPX...DVN AND ILX
SOUNDINGS RATHER DRY AND APPEARS BEST LIFT...ALBEIT WEAK SHOULD
REMAIN NORTH OF THE FORECAST AREA. HOWEVER WILL CONTINUE TO
MONITOR RADAR TRENDS UPSTREAM FOR SMALL PROBABILITY PRECIP CLIPS
FAR NORTHERN COUNTIES.
ELSEWHERE...DID LOWER TEMPS A FEW DEGREES OVERNIGHT AS THIN HIGH
CLOUDS AND LIGHTS WINDS HAVE ALLOWED TEMPS TO FALL INTO THE UPPER
TEENS OVER PARTS OF LINCOLN AND LANGLADE COUNTIES AND INTO THE LOW
TO MID 20S IN PARTS OF THE CENTRAL AND NORTHEAST FORECAST AREA. AS
UPPER SYSTEM CONTINUES TO APPROACH THE FORECAST AREA
OVERNIGHT...EXPECT HIGH-MID CLOUDS TO THICKEN SOME AND TEMPS
SHOULD BECOME STEADY OR PERHAPS RISE AFTER MIDNIGHT.
ESB
.PREV DISCUSSION...ISSUED AT 628 PM CST MON JAN 30 2012...
SHORT TERM...TONIGHT AND TUESDAY.
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW LIGHT SNOW
ASSOCIATED WITH A MID-LEVEL FGEN BAND ALONG AN ELEVATED WARM FRONT
HAS RAPIDLY PUSHED TO THE EAST EARLY THIS AFTERNOON LEAVING
WIDESPREAD MID AND HIGH CLOUDS OVERHEAD. THE SURFACE WARM FRONT IS
STILL LAGGING BEHIND FROM MINNEAPOLIS TO CHICAGO...BUT SE WINDS
NORTH OF THE BOUNDARY HAS BROUGHT WARMER MARINE AIR INTO
NORTHEAST WISCONSIN WHERE TEMPS HAVE REACHED INTO THE MIDDLE 30S.
DESPITE THE WARM ADVECTION...NO SIGN OF ANY STRATUS/DRIZZLE/FOG
DEVELOPMENT UPSTREAM SO FAR...BUT THE ABOVE 30F DEWPOINTS ARE NOW
REACHING INTO EASTERN IOWA AND NORTHERN ILLINOIS. AS WARM ADVECTION
CONTINUES UNABATED AHEAD OF LOW PRESSURE DEVELOPING OVER THE
NORTHERN ROCKIES...LOW STRATUS AND FOG POTENTIAL ARE THE MAIN
FORECAST CONCERNS.
TONIGHT...A SHORTWAVE TROUGH WILL MOVE ACROSS THE DAKOTAS AND PUSH
SURFACE LOW PRESSURE OVER THE NORTHERN MISSISSIPPI VALLEY. AHEAD OF
THE LOW...H850 WARM FRONT WILL LIFT ACROSS THE U.P. INTO
LAKE SUPERIOR. THE THREAT OF PRECIP WILL BE LOCATED ALONG THIS
BOUNDARY AND NORTH OF THE FORECAST AREA...SO HAVE REMOVED POPS FOR
TONIGHT. WILL STILL HAVE PLENTY OF MID AND UPPER MOISTURE AROUND
CARRIED IN BY THE JET STREAM TO MAKE FOR A PARTLY TO MOSTLY CLOUDY
NIGHT. THE BIGGEST FORECAST CHALLENGE TONIGHT WILL BE THE
POSSIBILITY OF FOG OR LOW STRATUS DEVELOPMENT LATE. SSW WILL CARRY
DEWPOINTS IN THE UPPER 20S TO LOWER 30S OVER THE MID-MISSISSIPPI
VALLEY INTO THE REGION TONIGHT. THE NAM IN PARTICULAR IS BULLISH ON
CREATING LOW STRATUS OR FOG BUT COULD BE ONE OF THOSE SCENARIOS
WHERE TEMPS JUST ABOVE THE SURFACE RISE COINCIDENT WITH DEW POINTS
WHICH WOULD CREATE SOME LOWER VSBYS AND FROST DEPOSITS BUT WITHOUT
ANY FOG OR STRATUS. NOT SEEING MUCH POTENTIAL FOR DRIZZLE AS THE
MOISTURE DOESNT APPEAR DEEP ENOUGH. SO WILL PUNT IT OFF TO THE
EVENING CREW UNTIL CAN SEE THE WHITES OF ITS EYES. WITH THE WARM
ADVECTION...LOW TEMPS WILL NOT FALL MUCH...FROM THE MID 20S NORTH TO
LOW 30S SE.
TUESDAY...LOW PRESSURE WILL CONTINUE TO TRACK EAST ALONG THE WARM
FRONT OVER THE U.P. SOUTH OF THE LOW TRACK...GULF MOISTURE WILL
SURGE NORTHEAST BUT LOOKS TO BYPASS THE REGION INTO LOWER MICHIGAN.
AS A RESULT...OUR AIR WILL ARRIVE FROM THE DRIER SOUTHERN GREAT
PLAINS WHICH WILL KEEP THE MID-LEVELS DRY DESPITE A WEAK PACIFIC
COOL FRONT PASSING ACROSS THE AREA IN THE AFTERNOON. AFTER SOME
MORNING MIST OR LOW STRATUS...SHOULD SEE PARTLY TO MOSTLY CLOUDY
SKIES ACROSS THE AREA IN THE AFTERNOON. HIGHS WILL BE WARM AFTER A
MILD START TO THE DAY...WITH HIGHS RANGING FROM THE UPPER 30S NORTH
TO MIDDLE 40S SOUTH.
LONG TERM...TUESDAY NIGHT THROUGH NEXT MONDAY. MILD WEATHER WILL
CONTINUE THROUGH THE REMAINDER OF THE WEEK AND INTO EARLY NEXT
WEEK. CLOUD COVER AND TEMPERATURES ARE THE PRIMARY CHALLENGE
THROUGH SATURDAY AS THERE IS LITTLE CHANCE OF ANY PRECIPITATION.
THE VERY MILD TEMPERATURES AND MELTING SNOW WILL LIKELY PRODUCE
LOW CLOUDS AND FOG AT SOME POINT...ESPECIALLY IN NORTHERN
WISCONSIN WHERE SNOW COVER IS A FOOT OR SO. BUT NOT CERTAIN ENOUGH
ABOUT WHEN THIS MIGHT OCCUR SO DID NOT MENTION ANY FOG IN THE
FORECAST. WE DO EXPECT SOME BY LATER IN THE WEEK.
THE MODELS DO BRING SOME SOUTHERN STREAM JET ENERGY FROM FOUR
CORNERS AREA FRIDAY INTO THE CENTRAL PLAINS SATURDAY AND SUNDAY.
THE EVOLUTION OF THE SYSTEM IS DIFFERENT FROM MODEL TO MODEL AND
RUN TO RUN SO DO NOT HAVE A LOT OF CONFIDENCE AT THIS POINT. THE
GFS SOLUTIONS COULD PRODUCE CONSIDERABLE SNOW OVER WESTERN
WISCONSIN IF IT WOULD VERIFY. THERE IS SOME DECENT AGREEMENT NOW
THAT AN UPPER RIDGE WILL FORM OVER THE WESTERN PART OF NORTH
AMERICA WITH A TROUGH EAST OF ROCKIES. THE MODELS HAVE ADVERTISED
THIS A COUPLE OF TIMES THIS WINTER BUT IT HAS NOT MATERIALIZED.
&&
.AVIATION...
FVR CONDITIONS EXPECTED OVERNIGHT OVER FORECAST AREA AS AIRMASS
AHEAD OF APPROACHING UPPER-LEVEL DISTURBANCE QUITE DRY AND BEST
LARGE-SCALE LIFT WILL BE CONFINED GENERALLY NORTH OF THE
WISCONSIN/MICHIGAN BORDER. EXCEPTION OVERNIGHT WILL BE AROUND IMT
EASTWARD TO LAKE MICHIGAN WHERE SCT MVFR CONDITIONS WILL PERSIST
INTO TUESDAY MORNING. SCATTERED VSBYS OF 3-5 MILES ALSO POSSIBLE
NEAR GRB AND THE FOX VALLEY SOUTHWARD AS LIGHT WINDS...THIN HIGH
CLOUDS AND INCREASING SURFACE DEW POINTS MAY LEAD TO SOME LIGHT FOG.
VFR CONDITIONS CAN BE EXPECTED ON TUESDAY...DESPITE PASSAGE OF
WEAK FRONTAL BOUNDARY ACROSS THE FORECAST AREA LATE INI THE
AFTERNOON. SOME SCATTERED MVFR CONDITIONS POSSIBLE RHI...CWA AND
AUW IMMEDIATELY IN THE WAKE OF FROPA AS WEAK CAA DEVELOPS.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
EB
AREA FORECAST DISCUSSION...UPDATED
NWS SAN JOAQUIN VALLEY - HANFORD CA
935 PM PST WED FEB 1 2012
.SYNOPSIS...
WEAK UPPER LEVEL DISTURBANCES WILL CONTINUE TO MOVE OVER THE
FORECAST AREA THIS WEEK PRODUCING INTERMITTENT SCATTERED MIDDLE AND
HIGH CLOUDS BUT LITTLE IF ANY PRECIPITATION. VALLEY FOG REMAINS A
POSSIBILITY DURING THE NIGHTS AND MORNINGS.
&&
.UPDATE...
WINDS HAVE BEEN GUSTING TO 35-40 MPH IN THE MOJAVE DESERT FROM BELOW
THE TEHACHAPI PASS TO ROSAMOND. THESE WINDS WILL SUBSIDE LATER
TONIGHT AS THE UPPER-LEVEL TROUGH CONTINUES TO MOVE EAST. THE WINDS
ARE LOCALIZED ALONG THE HIGHWAY 58 CORRIDOR FROM THE PASS TO MOJAVE
AND ALONG HIGHWAY 14 FROM MOJAVE TO ROSAMOND. EDWARDS AFB WAS
REPORTING LIGHT WINDS AT BOTH THE MAIN BASE AND THE NORTH BASE
AUXILIARY FIELD. HAVE ISSUED A SIGNIFICANT WEATHER ADVISORY FOR
THESE LOCALIZED WIND GUSTS THROUGH 0815Z /0015 PST/ THURSDAY.
&&
.DISCUSSION...
SATELLITE LOOPS SHOW AN UPPER-LEVEL TROUGH MOVING EAST OF CALIFORNIA
THIS EVENING. IN ITS WAKE...STRATOCUMULUS CLOUDS THAT FORMED ALONG
THE VALLEY-FACING SLOPES OF THE SOUTHERN SIERRA NEVADA AND THE
TEHACHAPI MOUNTAINS HAVE SLID BACK OVER PARTS OF THE SOUTH END OF
THE SAN JOAQUIN VALLEY.
DESPITE THE UPPER-LEVEL TROUGH...TEMPERATURES IN THE CENTRAL
CALIFORNIA INTERIOR REMAINED WELL ABOVE NORMAL TODAY. HIGHS IN THE
CENTRAL AND SOUTHERN SAN JOAQUIN VALLEY AS OF 1600 PST /00Z THURSDAY/
RANGED FROM 63 /AT LOS BANOS...MERCED REGIONAL AIRPORT AND
PORTERVILLE MUNICIPAL AIRPORT/ TO 69 /AT COALINGA/. THE HIGHS AT
BAKERSFIELD AND FRESNO /66 AND 65 DEGREES RESPECTIVELY/ WERE 7
DEGREES ABOVE NORMAL. COALINGA ALSO TIED WITH THE CHINA LAKE N.W.T.C.
AS THE WARMEST SPOT IN THE HANFORD WARNING/FORECAST AREA.
ONLY PATCHY FOG FORMED IN THE CENTRAL AND SOUTHERN SAN JOAQUIN VALLEY
THIS MORNING. WITH AN UPPER-LEVEL RIDGE BUILDING INTO CALIFORNIA
TONIGHT AND THURSDAY...EXPECT SOME FOG REDEVELOPMENT TOWARD DAYBREAK.
HOWEVER...THE MODELS FORECAST A LOW-LEVEL OFFSHORE FLOW TO DEVELOP
OVER CENTRAL CALIFORNIA AND THIS SHOULD DRY THE AIRMASS ENOUGH TO
KEEP FOG PATCHY.
THE MODELS KEEP THE UPPER-LEVEL RIDGE OVER CALIFORNIA THROUGH
FRIDAY. THE UPPER-LEVEL TROUGH THAT MOVED THROUGH CALIFORNIA TODAY
IS FORECAST TO CLOSE OFF INTO A LOW OVER COLORADO AND BUILD WESTWARD
INTO NEVADA FRIDAY AFTERNOON AND NIGHT. THIS WILL SPLIT THE RIDGE...
WITH 500-MB HEIGHTS OVER CALIFORNIA LOWERING TO AROUND 5640 METERS
BY 12Z /0400 PST/ SUNDAY. THIS SPLIT OF THE RIDGE WOULD ALLOW THE
WESTERLIES TO UNDERCUT THE LOW AND MOVE INTO CALIFORNIA. WILL AWAIT
SUBSEQUENT MODEL RUNS TO SEE IF THIS PATTERN VERIFIES AND WHAT THE
POTENTIAL IMPACT ON THE HANFORD WARNING/FORECAST AREA WOULD BE.
FOR NOW...THE FORECAST FOR THE NEXT FEW DAYS IS DRY AND UNSEASONABLY
WARM WITH PATCHY LATE NIGHT AND MORNING SAN JOAQUIN VALLEY FOG.
&&
.PREV DISCUSSION... /ISSUED 150 PM PST WED FEB 1 2012/
COOL AND DRY UPPER NORTHERLY FLOW PREVAILING OVER CENTRAL CA AT
THIS TIME AS OUR AREA REMAINS SITUATED IN BETWEEN A DEPARTED UPPER
TROUGH OVER THE GREAT BASIN AND AN OFFSHORE RIDGE. THE RIDGE IS
PROGGED BY THE 12Z WRF AND GFS TO AMPLIFY OFF THE CA COAST TONIGHT
THEN BUILD INLAND ON THURSDAY. ONSHORE P-GRADS HAVE STRENGTHENED
WITH KSFO-KLAS AT 10.4 MB AND KBFL-KNID AT 6.7 MB AT NOON TODAY.
HI RESOLUTION RUC INDICATING P-GRADS WILL MAX OUT LATER THIS
AFTERNOON THEN WEAKEN RAPIDLY THIS EVENING. THE INCREASED SURFACE
GRADIENTS WILL RESULT IN A PERIOD OF BREEZY CONDITIONS ACROSS THE
KERN COUNTY MOUNTAINS AND DESERTS THROUGH EARLY THIS EVENING...BUT
DO NOT EXPECT WINDS TO REACH WIDESPREAD ADVISORY CRITERIA. IN THE
MEANTIME...SOME UPSLOPE STRATOCUMULUS HAS FORMED OVER THE
SOUTHERN SIERRA FOOTHILLS WHILE SOME INSTABILITY CUMULUS HAS
PUSHED SOUTHWARD INTO MERCED COUNTY. EXPECT THESE CLOUDS TO
DISSIPATE TONIGHT AS CAA CONTINUES TONIGHT AND MIXES OUT THE
ATMOSPHERE. THE NORTHERLY FLOW PATTERN WILL ALSO INHIBIT THE
DEVELOPMENT OF WIDESPREAD FOG IN THE SAN JOAQUIN VALLEY
TONIGHT...BUT THERE IS ENOUGH RESIDUAL LOW LEVEL MOISTURE NEAR THE
VALLEY FLOOR SO SOME PATCHY FOG IS NOT OUT OF THE QUESTION FOR
TONIGHT.
MODEL CONSENSUS INDICATES THE RIDGE WILL KEEP DRY CONDITIONS OVER
OUR AREA THURSDAY THROUGH THE UPCOMING WEEKEND. TEMPERATURES WILL
RISE TO ABOVE SEASONAL NORMALS AS THE RIDGE STRENGTHENS OVER THE
AREA FRIDAY THROUGH THE WEEKEND. THE ONLY FORECAST PROBLEM FOR
THIS PERIOD WILL BE THE THE EXTENT OF ANY NIGHT AND MORNING FOG
IN THE SAN JOAQUIN VALLEY AND SUBSEQUENT IMPACT IT MAY HAVE ON
TEMPERATURES. THE INCREASING SUN ANGLE WILL LIKELY ALLOW FOR ANY
FOG THAT DOES FOR TO COMPLETELY BURN OFF BY LATE MORNING EACH
DAY...THAT IS UNLESS THE RIDGE COMPLETELY SQUISHES OUT ANY LOW
LEVEL MOISTURE.
THE 12Z GFS AND ECMWF BOTH INDICATE THE RIDGE WILL BREAK DOWN ON
MONDAY AND A SPLIT TROUGH WILL REACH THE CA COAST BY TUESDAY.
THE ECMWF IS SOMEWHAT MORE ROBUST WITH THE SPLITTING AND JUST
BRINGING A DEFORMATION BAND OF MID/UPPER LEVEL MOISTURE THROUGH
OUR AREA WHILE THE GFS HOLDS MORE OF IT TOGETHER AND BRING SOME
DEEPER MOISTURE INTO OUR AREA WHILE IT MOVES THROUGH CA ON TUESDAY
AND TUESDAY NIGHT. HAVE DECIDED TO COMPROMISE BETWEEN THE TWO
SOLUTIONS AND KEEP MENTION OF A SLIGHT CHANCE TO LOW CHANCE OF
RAIN AND MOUNTAIN SNOW FOR FRESNO COUNTY NORTHWARD TUESDAY AND
TUESDAY NIGHT TAPERING TO MOUNTAIN SHOWERS ON WEDNESDAY. ENSEMBLE
MEMBER AGREEMENT IS POOR SO DO NOT HAVE A LOT OF CONFIDENCE IN
DAYS 6 AND 7 AT THIS TIME.
&&
.AVIATION...
IN THE SAN JOAQUIN VALLEY...LOCAL IFR/LIFR VISIBILITIES CAN BE
EXPECTED BETWEEN 09Z AND 18Z THURSDAY. OTHERWISE...AREAS OF MVFR IN
HAZE CAN BE EXPECTED THROUGH 06Z FRIDAY.
ELSEWHERE...VFR CONDITIONS WILL PREVAIL ACROSS THE CENTRAL CALIFORNIA
INTERIOR THROUGH 06Z FRIDAY.
&&
.AIR QUALITY ISSUES...
ON THURSDAY FEBRUARY 2 2012...UNHEALTHY FOR SENSITIVE GROUPS IN
KERN...KINGS AND TULARE COUNTIES. FIREPLACE/WOOD STOVE BURNING IS
PROHIBITED IN FRESNO...KERN...KINGS...MADERA AND TULARE COUNTIES.
FURTHER INFORMATION IS AVAILABLE AT VALLEYAIR.ORG
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
PUBLIC...SANGER
AVN/FW...MV/SANGER
SYNOPSIS...PJ
PREV DISCUSSION...DS
WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION
NWS SAN JOAQUIN VALLEY - HANFORD CA
830 PM PST WED FEB 1 2012
.SYNOPSIS...
WEAK UPPER LEVEL DISTURBANCES WILL CONTINUE TO MOVE OVER THE
FORECAST AREA THIS WEEK PRODUCING INTERMITTENT SCATTERED MIDDLE AND
HIGH CLOUDS BUT LITTLE IF ANY PRECIPITATION. VALLEY FOG REMAINS A
POSSIBILITY DURING THE NIGHTS AND MORNINGS.
&&
.DISCUSSION...
SATELLITE LOOPS SHOW AN UPPER-LEVEL TROUGH MOVING EAST OF CALIFORNIA
THIS EVENING. IN ITS WAKE...STRATOCUMULUS CLOUDS THAT FORMED ALONG
THE VALLEY-FACING SLOPES OF THE SOUTHERN SIERRA NEVADA AND THE
TEHACHAPI MOUNTAINS HAVE SLID BACK OVER PARTS OF THE SOUTH END OF
THE SAN JOAQUIN VALLEY.
DESPITE THE UPPER-LEVEL TROUGH...TEMPERATURES IN THE CENTRAL
CALIFORNIA INTERIOR REMAINED WELL ABOVE NORMAL TODAY. HIGHS IN THE
CENTRAL AND SOUTHERN SAN JOAQUIN VALLEY AS OF 1600 PST /00Z THURSDAY/
RANGED FROM 63 /AT LOS BANOS...MERCED REGIONAL AIRPORT AND
PORTERVILLE MUNICIPAL AIRPORT/ TO 69 /AT COALINGA/. THE HIGHS AT
BAKERSFIELD AND FRESNO /66 AND 65 DEGREES RESPECTIVELY/ WERE 7
DEGREES ABOVE NORMAL. COALINGA ALSO TIED WITH THE CHINA LAKE N.W.T.C.
AS THE WARMEST SPOT IN THE HANFORD WARNING/FORECAST AREA.
ONLY PATCHY FOG FORMED IN THE CENTRAL AND SOUTHERN SAN JOAQUIN VALLEY
THIS MORNING. WITH AN UPPER-LEVEL RIDGE BUILDING INTO CALIFORNIA
TONIGHT AND THURSDAY...EXPECT SOME FOG REDEVELOPMENT TOWARD DAYBREAK.
HOWEVER...THE MODELS FORECAST A LOW-LEVEL OFFSHORE FLOW TO DEVELOP
OVER CENTRAL CALIFORNIA AND THIS SHOULD DRY THE AIRMASS ENOUGH TO
KEEP FOG PATCHY.
THE MODELS KEEP THE UPPER-LEVEL RIDGE OVER CALIFORNIA THROUGH
FRIDAY. THE UPPER-LEVEL TROUGH THAT MOVED THROUGH CALIFORNIA TODAY
IS FORECAST TO CLOSE OFF INTO A LOW OVER COLORADO AND BUILD WESTWARD
INTO NEVADA FRIDAY AFTERNOON AND NIGHT. THIS WILL SPLIT THE RIDGE...
WITH 500-MB HEIGHTS OVER CALIFORNIA LOWERING TO AROUND 5640 METERS
BY 12Z /0400 PST/ SUNDAY. THIS SPLIT OF THE RIDGE WOULD ALLOW THE
WESTERLIES TO UNDERCUT THE LOW AND MOVE INTO CALIFORNIA. WILL AWAIT
SUBSEQUENT MODEL RUNS TO SEE IF THIS PATTERN VERIFIES AND WHAT THE
POTENTIAL IMPACT ON THE HANFORD WARNING/FORECAST AREA WOULD BE.
FOR NOW...THE FORECAST FOR THE NEXT FEW DAYS IS DRY AND UNSEASONABLY
WARM WITH PATCHY LATE NIGHT AND MORNING SAN JOAQUIN VALLEY FOG.
&&
.PREV DISCUSSION... /ISSUED 150 PM PST WED FEB 1 2012/
COOL AND DRY UPPER NORTHERLY FLOW PREVAILING OVER CENTRAL CA AT
THIS TIME AS OUR AREA REMAINS SITUATED IN BETWEEN A DEPARTED UPPER
TROUGH OVER THE GREAT BASIN AND AN OFFSHORE RIDGE. THE RIDGE IS
PROGGED BY THE 12Z WRF AND GFS TO AMPLIFY OFF THE CA COAST TONIGHT
THEN BUILD INLAND ON THURSDAY. ONSHORE P-GRADS HAVE STRENGTHENED
WITH KSFO-KLAS AT 10.4 MB AND KBFL-KNID AT 6.7 MB AT NOON TODAY.
HI RESOLUTION RUC INDICATING P-GRADS WILL MAX OUT LATER THIS
AFTERNOON THEN WEAKEN RAPIDLY THIS EVENING. THE INCREASED SURFACE
GRADIENTS WILL RESULT IN A PERIOD OF BREEZY CONDITIONS ACROSS THE
KERN COUNTY MOUNTAINS AND DESERTS THROUGH EARLY THIS EVENING...BUT
DO NOT EXPECT WINDS TO REACH WIDESPREAD ADVISORY CRITERIA. IN THE
MEANTIME...SOME UPSLOPE STRATOCUMULUS HAS FORMED OVER THE
SOUTHERN SIERRA FOOTHILLS WHILE SOME INSTABILITY CUMULUS HAS
PUSHED SOUTHWARD INTO MERCED COUNTY. EXPECT THESE CLOUDS TO
DISSIPATE TONIGHT AS CAA CONTINUES TONIGHT AND MIXES OUT THE
ATMOSPHERE. THE NORTHERLY FLOW PATTERN WILL ALSO INHIBIT THE
DEVELOPMENT OF WIDESPREAD FOG IN THE SAN JOAQUIN VALLEY
TONIGHT...BUT THERE IS ENOUGH RESIDUAL LOW LEVEL MOISTURE NEAR THE
VALLEY FLOOR SO SOME PATCHY FOG IS NOT OUT OF THE QUESTION FOR
TONIGHT.
MODEL CONSENSUS INDICATES THE RIDGE WILL KEEP DRY CONDITIONS OVER
OUR AREA THURSDAY THROUGH THE UPCOMING WEEKEND. TEMPERATURES WILL
RISE TO ABOVE SEASONAL NORMALS AS THE RIDGE STRENGTHENS OVER THE
AREA FRIDAY THROUGH THE WEEKEND. THE ONLY FORECAST PROBLEM FOR
THIS PERIOD WILL BE THE THE EXTENT OF ANY NIGHT AND MORNING FOG
IN THE SAN JOAQUIN VALLEY AND SUBSEQUENT IMPACT IT MAY HAVE ON
TEMPERATURES. THE INCREASING SUN ANGLE WILL LIKELY ALLOW FOR ANY
FOG THAT DOES FOR TO COMPLETELY BURN OFF BY LATE MORNING EACH
DAY...THAT IS UNLESS THE RIDGE COMPLETELY SQUISHES OUT ANY LOW
LEVEL MOISTURE.
THE 12Z GFS AND ECMWF BOTH INDICATE THE RIDGE WILL BREAK DOWN ON
MONDAY AND A SPLIT TROUGH WILL REACH THE CA COAST BY TUESDAY.
THE ECMWF IS SOMEWHAT MORE ROBUST WITH THE SPLITTING AND JUST
BRINGING A DEFORMATION BAND OF MID/UPPER LEVEL MOISTURE THROUGH
OUR AREA WHILE THE GFS HOLDS MORE OF IT TOGETHER AND BRING SOME
DEEPER MOISTURE INTO OUR AREA WHILE IT MOVES THROUGH CA ON TUESDAY
AND TUESDAY NIGHT. HAVE DECIDED TO COMPROMISE BETWEEN THE TWO
SOLUTIONS AND KEEP MENTION OF A SLIGHT CHANCE TO LOW CHANCE OF
RAIN AND MOUNTAIN SNOW FOR FRESNO COUNTY NORTHWARD TUESDAY AND
TUESDAY NIGHT TAPERING TO MOUNTAIN SHOWERS ON WEDNESDAY. ENSEMBLE
MEMBER AGREEMENT IS POOR SO DO NOT HAVE A LOT OF CONFIDENCE IN
DAYS 6 AND 7 AT THIS TIME.
&&
.AVIATION...
IN THE SAN JOAQUIN VALLEY...LOCAL IFR/LIFR VISIBILITIES CAN BE
EXPECTED BETWEEN 09Z AND 18Z THURSDAY. OTHERWISE...AREAS OF MVFR IN
HAZE CAN BE EXPECTED THROUGH 06Z FRIDAY.
ELSEWHERE...VFR CONDITIONS WILL PREVAIL ACROSS THE CENTRAL CALIFORNIA
INTERIOR THROUGH 06Z FRIDAY.
&&
.AIR QUALITY ISSUES...
ON THURSDAY FEBRUARY 2 2012...UNHEALTHY FOR SENSITIVE GROUPS IN
KERN...KINGS AND TULARE COUNTIES. FIREPLACE/WOOD STOVE BURNING IS
PROHIBITED IN FRESNO...KERN...KINGS...MADERA AND TULARE COUNTIES.
FURTHER INFORMATION IS AVAILABLE AT VALLEYAIR.ORG
&&
.HNX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
PUBLIC...SANGER
AVN/FW...MV/SANGER
SYNOPSIS...PJ
PREV DISCUSSION...DS
WEATHER.GOV/HANFORD
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1255 AM EST THU FEB 2 2012
UPDATED AVIATION DISCUSSION FOR 06Z TAFS
.UPDATE...
BAND OF CONVECTIVE SNOW SHOWERS (H8-H7 LAPSE RATES OVR 8.5 C/KM) ARE
PUSHING INTO WESTERN LAKE SUPERIOR AHEAD OF SHORTWAVE. MAIN CHANGE TO
EARLIER FCST UPDATE WAS TO INCLUDE MENTION OF FZG PCPN IN FAR WEST
THROUGH AROUND 09Z. RISK OF MUCH FREEZING PCPN IS SMALL...BUT THERE
WAS A BRIEF PERIOD OF FZRA AT KDLH AND RUC13 SHOWS 925MB TEMPS/WET-
BULB ZERO TEMPS RIGHT AROUND 0C OVR KIWD AT 06Z. DRYING IS VERY
EVIDENT BEHIND THE LINE OF WINTRY PCPN...SO EXPECT JUST A BRIEF
PERIOD OF SNOW AND MAYBE LGT FZRA/FZDZ OVR FAR WEST WITH JUST LGT
SNOW/FLURRIES BY TIME IT REACHES CNTRL CWA TOWARD DAYBREAK THURSDAY.
UPDATED GRIDS TO SHOW THESE TRENDS. TEMPS HAVE FALLEN INTO MID TEENS
ALONG WI BORDER WHERE SKIES CLEARED. IN THOSE AREAS...SHOULD SEE
TEMPS RISE UP THROUGH LATER TONIGHT AS CLOUDS AND SNOW SHOWERS MOVE IN
FM THE WEST. ELSEWHERE... TRENDS IN FCST FOR TEMPS AND SKY LOOK GOOD
FOR NOW.
&&
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 423 PM EST WED FEB 1 2012
LATE THIS AFTERNOON THROUGH EARLY EVENING...MAIN ISSUE WILL BE
CLEARING SKIES NEAR THE WI BORDER. TREND IS EXPECTED TO CONTINUE
THROUGH EARLY EVENING BEFORE COVERAGE INCREASES AGAIN OVERNIGHT.
TEMPERATURE TRENDS WILL NEED TO BE MONITORED OVERNIGHT AS MODEL
GUIDANCE...ESPECIALLY THE NAM...INDICATED TEMPERATURES DROPPING INTO
THE LOWER 20S. LOW TEMPERATURES LATE THIS EVENING WILL BE LARGELY
DEPENDENT UPON THE SKY COVER.
OVERNIGHT TONIGHT THROUGH THURSDAY MORNING...MODELS ARE IN GOOD
AGREEMENT WITH A SHORT WAVE MOVING FROM MINNESOTA INTO WESTERN UPPER
MI AFTER 00Z TONIGHT. AHEAD OF THE SHORTWAVE EXPECT SNOW SHOWERS TO
DEVELOP AND PROGRESS EASTWARD THROUGH THURSDAY MORNING. WHILE THE
SNOW SHOULD REMAIN ON THE LIGHT SIDE...THE AREAS MORE LIKELY TO SEE
LIGHT ACCUMULATION WOULD BE OVER THE KEWEENAW AS THE GFS AND THE NAM
SHOW THE GREATEST FORCING OVER THE CENTRAL GREAT LAKES AS INDICATED
BY OMEGA LOCATED IN THE DGZ. THERE IS A POSSIBILITY THAT SOME
DRIZZLE MAY MOVE AHEAD OF THE SYSTEM...HOWEVER WITH THE WETBULB
TEMPERATURE REMAINING BELOW ZERO AND ABSENCE OF ANY ADVECTION EXPECT
THAT ANY DRIZZLE WOULD BE VERY BRIEF. BY THURSDAY
AFTERNOON...PRECIPITATION SHOULD COME TO AN END AS SHORTWAVE PRESSES
EASTWARD IN THE FAR EASTERN PORTION OF THE U.P. SKY COVER WILL
LINGER AS LOW LEVEL MOISTURE REMAINS IN PLACE.
TEMPERATURES THROUGH THE SHORT TERM PERIOD SHOULD BE ABOVE NORMAL.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 423 PM EST WED FEB 1 2012
SHORTWAVE SLIDING THROUGH THE AREA ON THURS AFTN WILL BE SHIFTING E
OF THE AREA AT THE START OF THE PERIOD...ALLOWING HIGH PRESSURE TO
START TO BUILD IN TO THE UPPER GREAT LKS THURS NIGHT. BUT...DRY MID
LEVEL AIR FLOWING SE IN THE NW FLOW...ALONG WITH WEAK H875
WAA...WILL KEEP LLVL INVERSION IN PLACE AND SHOULD KEEP LOW CLOUDS
TRAPPED OVER THE AREA ON THURS NIGHT. WITH H900-880 TEMPS AROUND
-8C...THERE MAY BE ENOUGH LK INFLUENCE TO ENHANCE THE CLOUDS...WHICH
COMBINED WITH LIGHT NNW FLOW COULD LEAD TO SOME UPSLOPE --SHSN/DZ
OVER THE HIGHER TERRAIN NEAR LK SUPERIOR. IF ABUNDANT LLVL MOISTURE
ON 12Z NAM AND OUR LOCAL WRF-ARW PANS OUT WILL LIKELY SEE WIDESPREAD
FOG...ESPECIALLY OVER THE HIGHER TERRAIN...SO ADDED A MENTION OF
PATCHY FOG TO THE FCST FOR THURS NIGHT.
HIGH PRESSURE WILL SETTLE INTO THE UPPER GREAT LKS ON FRI FROM WRN
ONTARIO...WHICH WILL WEAKEN THE WINDS FURTHER ACROSS THE AREA. A
SHORTWAVE DROPPING THROUGH THE NW FLOW WILL BRUSH THE AREA DURING
THE DAY...BUT LIMITED MOISTURE ASSOCIATED WITH IT SHOULDN/T LEAD TO
ANY PCPN WITH MID LVL DRY AIR STILL IN PLACE. LOW CLOUDS FROM THURS
NIGHT SHOULD STILL BE COVERING THE AREA FOR MUCH OF FRI...BUT
--SHSN/DZ POTENTIAL LOOKS TO DIMINISH WITH LACK OF UPSLOPE FLOW AND
LLVL DRYING FROM THE SFC HIGH.
DRIER AIR ARRIVES FRI NIGHT AND SAT WITH THE SFC HIGH AND AREA BEING
BETWEEN UPPER LOW ROTATING JUST E OF THE CNTRL ROCKIES AND RIDGE
OVER THE CANADIAN PRAIRIES. OVERALL SUBSIDENCE AND DRY AIR ROTATING
IN FROM CANADA...WHICH LEADS TO A DRY AND CONTINUED WARMER THAN
NORMAL PERIOD. DROPPED LOWS SEVERAL DEGREES ON FRI NIGHT...AS LIGHT
WINDS...CLEAR SKIES...AND PWAT VALUES AROUND 45 PERCENT OF NORMAL
SUPPORTS DECENT RADIATIONAL COOLING.
DAYS 4 THROUGH 7 /SAT NIGHT THROUGH NEXT WEDNESDAY/...
FIRST PART OF THE PERIOD DEPENDS ON THE TRACK OF THE UPPER LOW
EXITING THE CNTRL PLAINS AND ASSOCIATED SFC FEATURES. STILL
DIFFERING OPINIONS IN THE DETERMINISTIC AND ENS MEMBERS ON THE
HANDLING OF THIS FEATURE. MOST HAVE THE IDEA OF THE UPPER LOW
SHIFTING EAST SAT NIGHT INTO SUN NIGHT AND THROUGH THE LOWER GREAT
LKS...BUT AS IS NORMALLY THE CASE WITH THESE TYPES OF SYSTEMS...THE
EXACT TIMING/LOCATION REMAINS TO BE SEEN. LARGE SPREAD IN THE
ENSEMBLE MEMBERS TOO...SO DON/T HAVE A WHOLE LOT OF CONFIDENCE IN
EXACT FEATURES AND WILL FOLLOW A CONSENSUS FOR THE FORECAST.
THUS...HAVE A DRY FCST ACROSS THE CWA FOR THE SECOND HALF OF THE
WEEKEND AND PARTLY TO MOSTLY CLEAR SKIES...ALTHOUGH THE SRN HALF OF
THE CWA MAY END UP SEEING MORE SCT/BKN MID-HIGH CLOUDS AS MAIN AREA
OF SYSTEM PUSHES S OF THE AREA.
GFS/ECMWF SHOWING COLDER H850 TEMPS SURGING IN TUES BEHIND A COLD
FRONT DROPPING THROUGH THE AREA ON MON NIGHT. COLD FRONT LOOKS TO
HAVE LIMITED MOISTURE ASSOCIATED WITH IT...WHICH IS ALSO THE CASE
BEHIND IT. THIS WILL BRING COLDER H850 AIR...TOWARDS -16C...AND
CHANCES OF LES TO NNW WIND FAVORED LOCATIONS AND BUMPED UP POPS SOME
IN THOSE AREAS TUES AND TUES NIGHT. WITH LIMITED MOISTURE...WILL
KEEP TUES NIGHT INTO WED DRY AS WINDS BACK TO THE W .
&&
.AVIATION /FOR THE 06Z TAF ISSUANCE/...
ONSET OF -SN IS VERY CLOSE TO IWD AT ISSUANCE TIME. PER RADAR AND
OBS FROM ASX...EXPECT ONLY 30-45 MINS OF MODERATE SN WITH VIS
DROPPING TO AROUND 2SM. THIS BAND WILL CONTINUE EAST OVERNIGHT AND
REACH CMX AROUND 10Z...AND SAW AROUND 12Z. ONLY A 2-3 HOUR SPAN OF
-SN IS EXPECTED WITH MINIMAL VIS OBSTRUCTIONS. CIG FORECAST IS
SOMEWHAT DIFFICULT INTO THE MORNING AT CMX AS UPSLOPE FLOW WILL
BECOME A FACTOR AND BRING LEVELS INTO IFR RANGE. DAYTIME HEATING
WILL HELP RAISE THESE BACK TO MVFR LEVELS...BUT IFR CIGS WILL RETURN
AFTER DARK. DRIER AIR MOVING IN FROM THE WEST ON THURSDAY WILL
SLOWLY ERODE CLOUDS AT IWD. OTHERWISE...WINDS WILL REMAIN UNDER
10KTS AND GRADUALLY VEER TO THE WEST AT ALL SITES BY THURSDAY
MORNING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 423 PM EST WED FEB 1 2012
IN THE SHORT TERM...WIND AND WAVES SHOULD REMAIN FAIRLY LIGHT OVER
THE LAKE AS PRESSURE GRADIENT REMAINS RELAXED. THE NEXT CHANCE OF
INCREASED WINDS WILL MOVE INTO THE AREA LATE MONDAY AND TUESDAY AS
PRESSURE GRADIENT TIGHTENS BETWEEN AND AREA OF HIGH PRESSURE LOCATED
OVER THE NORTHERN PLAINS AND A LOW PRESSURE CENTERED OVER THE MID
ATLANTIC STATES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...JLA
SHORT TERM...KEC
LONG TERM...SRF
AVIATION...TK
MARINE...KEC
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1159 PM EST WED FEB 1 2012
.AVIATION...
//DISCUSSION...
EXTENSIVE/SOLID MVFR STRATUS DECK TIED TO RESIDUAL LOW LEVEL
THERMAL TROUGHING WILL STRUGGLE TO CLEAR TONIGHT AND EARLY
THURSDAY. CEILINGS WILL HOVER PREDOMINATELY WITHIN THE 2000-2500 FT
RANGE...BUT MAY EASE DOWN BRIEFLY BELOW 2K FT /ESPECIALLY PTK AND
FNT/ DURING THE PRE-DAWN HOURS. THE ONSET OF DAYTIME MIXING WILL
AGAIN WORK TOWARD SCATTERING THIS DECK ON THURSDAY...MOST LIKELY
FROM SOUTH TO NORTH LATE IN THE DAY AS THE LOW LEVEL THERMAL
PROFILE FINALLY WARMS SUFFICIENTLY ENOUGH TO HELP MIX OUT THAT
RESIDUAL MOIST LAYER.
//DTW THRESHOLD THREATS...
* HIGH CONFIDENCE THAT CEILING WILL REMAIN BELOW 5000 FEET
TONIGHT. MEDIUM CONFIDENCE ON THURSDAY.
&&
.PREV DISCUSSION...ISSUED 340 PM EST WED FEB 1 2012
SHORT TERM...THIS EVENING AND TONIGHT
HIGH PRESSURE SYSTEM OVER THE UPPER MISSISSIPPI VALLEY WILL
BUILD OVER THE GREAT LAKES OVERNIGHT WITH THE RIDGE AXIS OVERHEAD BY
AROUND 12Z. WITH THE PRESSURE GRADIENT ALREADY RELAXING...WIND
SPEEDS ALREADY ON THE DECLINE WILL CONTINUE UNTIL THEY ARE LIGHT AND
VARIABLE BY MORNING. THE MAIN FORECAST CONCERN IS WITH CLOUD/FOG
POTENTIAL FOR THE OVERNIGHT. STRATUS DECK AROUND 3KFT MANAGED TO
FILL IN OVER ALL OF SE MI THIS MORNING EXTENDING BACK WEST INTO
IA/MN...UNDER THE NORTH SIDE OF THE RIDGE AXIS THAT WILL BE MOVING
OVERHEAD TONIGHT. EXPECT THIS LOW STRATUS DECK TO THIN OUT SOMEWHAT
THIS EVENING WHILE HIGHER CIRRUS CLOUDS THICKEN TONIGHT. RUC MODEL
SOUNDINGS AGREE WITH THIS THINKING THOUGH IT KEEPS LOW LEVEL
MOISTURE VALUES QUITE HIGH IN THE LOWEST 3KFT. THE NAM DOES ITS
USUAL AND IS EVEN MORE ROBUST WITH BOUNDARY LAYER SO LEANING MORE
TOWARD RUC. SO MODELS SHOW THERE IS POTENTIAL FOR THE STRATUS TO
LINGER LONGER THROUGH THE NIGHT. EVEN THOUGH MANY OF THE ASOS
STATIONS IN IA/MN/WI REPORTED FOG WITH VISIBILITY RESTRICTIONS DOWN
TO 2-4 MILES EARLY THIS MORNING...THE ABUNDANT CLOUD COVER WE WILL
HAVE IN PLACE SHOULD PREVENT MUCH FOG FORMATION IF ANY. RAISED MIN
TEMPS TONIGHT A DEGREE OR 2 TO ACCOUNT FOR THE THICKER CLOUDS.
LONG TERM...THURSDAY THROUGH NEXT WEDNESDAY
FORECAST CONTINUES TO LOOK FAIRLY QUIET DURING THE EXTENDED
PERIOD...AT LEAST FOR FEBRUARY. TEMPERATURES WILL CONTINUE TO RUN
ABOVE NORMAL INTO THE BEGINNING OF NEXT WEEK BEFORE A STRONG COLD
FRONT DROPS TEMPERATURES BACK CLOSER TO NORMAL NEXT WEDNESDAY.
UPPER SHORTWAVE OVER SOUTHERN MANITOBA THIS AFTERNOON WILL DROP DOWN
ACROSS THE NORTHERN GREAT LAKES THURSDAY. THIS SHOULD KEEP THE
SURFACE RIDGE INTACT OVER SOUTHEAST LOWER MICHIGAN...WHILE A WEAK
SURFACE TROUGH SLIDES ACROSS NORTHERN MICHIGAN IN RESPONSE. THINK
LIGHT SNOW SHOWERS WILL STAY NORTH OF THE AREA AND HAVE KEPT THE
FORECAST DRY...WITH THE MAIN IMPACT FROM THIS SHORTWAVE EXPECTED TO
BE AN INCREASE IN MID LEVEL MOISTURE OVER CENTRAL MICHIGAN. MODEL
FORECAST SOUNDINGS THROUGH THURSDAY NIGHT KEEP A SUBSIDENCE
INVERSION IN PLACE ACROSS SOUTHEAST MICHIGAN...GENERALLY BETWEEN
900-800MB. ALTHOUGH GFS/NAM DO NOT SHOW AN OVERABUNDANCE OF
LOW-LEVEL MOISTURE REMAINING TRAPPED IN THE LOWER LEVELS...DID LEAN
MORE PESSIMISTIC WITH THE SKY COVER FORECAST (MORE CLOUDS) THAN
MODELS SUGGEST GIVEN POOR MIXING AND LIGHT WEST TO NORTHWEST FLOW
OFF LAKE MICHIGAN. ASSUMING THERE IS A LOWER CLOUD DECK...WILL HAVE
TO SEE IF MID-LEVEL MOISTURE OVERRUNNING ANY MOISTURE TRAPPED
UNDERNEATH THE SUBSIDENCE INVERSION COULD SEED LOWER CLOUDS ACROSS
CENTRAL MICHIGAN...WHICH WOULD MAYBE PRODUCE SOME FLURRIES. GIVEN
THE EXPECTATION FOR MORE CLOUDS AND VERY LIGHT WINDS/POOR
MIXING...WENT ON THE COOL SIDE OF MOS GUIDANCE FOR HIGHS
THURSDAY...IN THE MID 30S TO LOW 40S.
THE RIDGE WILL THEN RESTRENGTHEN OVER THE CENTRAL GREAT LAKES
THURSDAY NIGHT AND FRIDAY...BEFORE ANOTHER UPPER SHORTWAVE DROPS
DOWN THROUGH THE CENTRAL GREAT LAKES FRIDAY NIGHT. GFS/NAM BRING A
WEAK FRONT DOWN ACROSS THE AREA WITH THIS FEATURE...BUT IT LOOKS
MOISTURE STARVED AND SHOULD DO LITTLE BUT INCREASE CLOUDS ONCE
AGAIN. NAM IS SLOWER WITH BOTH THE FRONT AND SOUTHWARD PROGRESS WITH
THIS WAVE ACROSS THE GREAT LAKES FRIDAY/FRIDAY NIGHT...AND HAVE
THEREFORE HEAVILY FAVORED THE OTHER MODELS WITH THE ARRIVAL OF
LOW-LEVEL MOISTURE AND PRECIPITATION LATE FRIDAY NIGHT INTO
SATURDAY. WITH THE SLOWER TIMING...NAM ALLOWS AN APPROACHING LOW
PRESSURE SYSTEM AND ASSOCIATED AREA OF DEFORMATION TO MAKE QUICKER
AND FURTHER INROADS INTO THE SOUTHERN GREAT LAKES.
REX BLOCK PATTERN WILL DEVELOP OVER THE WEST COAST BY FRIDAY...PER
STRONG CONSENSUS FROM FORECAST MODELS. THIS BLOCK WILL THEN VERY
SLOWLY MAKES IT WAY EAST INTO THE CENTRAL CONUS AND TOPPLE OVER THE
WEEKEND. MODELS REMAIN VERY DIVIDED ON HOW LONG IT WILL TAKE THE
UPPER LOW ON THE SOUTHERN END OF THE BLOCK TO LIFT UP INTO THE
SOUTHERN GREAT LAKES. SPREAD IS ANYWHERE FROM SATURDAY NIGHT (12Z
GFS) TO EARLY MONDAY (12Z GEM)...AND CONFIDENCE SURROUND TIMING OF
WEATHER IMPACTS FROM THIS FEATURE ARE VERY LOW. UKMET/GEM/EURO KEEP
THE SYSTEM FAR ENOUGH SOUTH OF THE AREA NOW TO SUPPORT A DRY
FORECAST THROUGH AT LEAST SATURDAY NIGHT. DID HOWEVER KEEP A SLIGHT
CHANCE FOR RAIN/SNOW NEAR THE OHIO BORDER SATURDAY AFTERNOON AND
OVERNIGHT...WITH LOW CHANCES FOR LIGHT SNOW SHOWERS BY SUNDAY NIGHT.
UPPER TROUGHING LOOKS TO BUILD OVER THE NORTHEASTERN PORTION OF
NORTH AMERICA AND THE GREAT LAKES TOWARDS THE MIDDLE OF THE
WEEK...WITH SEVERAL SHORTWAVE TROUGHS DROPPING DOWN ACROSS THE AREA
MONDAY THROUGH WEDNESDAY. GFS/EURO ALSO AGREE WITH A FAIRLY STRONG
COLD FRONT DROPPING DOWN THROUGH MICHIGAN ON TUESDAY (THOUGH THERE
REMAIN SLIGHT TIMING DIFFERENCES). THIS WOULD BRING A QUICK SHOT OF
SNOW SHOWERS AND DROP TEMPERATURES BACK DOWN TO NEAR NORMAL BY
WEDNESDAY.
MARINE...
HIGH PRESSURE OVER THE WESTERN GREAT LAKES WILL BUILD EASTWARD
OVERNIGHT WITH THE RIDGE AXIS ACROSS LAKE HURON BY THURSDAY MORNING.
THE PRESSURE GRADIENT HAS ALREADY WEAKENED SUBSTANTIALLY THROUGH THE
DAY ALLOWING WINDS TO DECREASE WITH MAX GUSTS REACHING 20 KNOTS OVER
THE OPEN WATERS OF LAKE HURON. WINDS AND WAVE WILL CONTINUE TO
DECREASE THROUGH THE NIGHT AS THE RIDGE AXIS DRAWS NEARER. THIS HIGH
PRESSURE SYSTEM WILL PRODUCE VERY FAVORABLE MARINE CONDITIONS INTO
THE WEEKEND. A LOW PRESSURE TROUGH WILL PASS THROUGH THE REGION ON
THURSDAY...THOUGH IT WILL BE VERY WEAK AND WILL MOST LIKELY NOT BE
ABLE TO PUT A DENT IN THE LARGER SCALE RIDGE IN PLACE.
&&
.DTX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LAKE HURON...NONE.
LAKE ST CLAIR...NONE.
MI WATERS OF LAKE ERIE...NONE.
&&
$$
AVIATION.....MR
SHORT TERM...DRK
LONG TERM....HLO
MARINE.......DRK
YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE
AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1156 PM EST WED FEB 1 2012
LATEST UPDATE...AVIATION...
.SYNOPSIS...(415 PM EST WED FEB 1 2012)
HIGH PRESSURE WILL PROVIDE TRANQUIL WEATHER INTO FRIDAY WITH
GENERALLY PARTLY CLOUDY SKIES. MILD CONDITIONS WILL CONTINUE WITH
HIGH TEMPERATURES FORECAST TO PUSH TO AROUND 40 BOTH THURSDAY AND
FRIDAY. NORMAL HIGHS FOR THIS TIME OF YEAR AROUND NEAR 30 DEGREES.
A SYSTEM MAY APPROACH THE SOUTHERN GREAT LAKES OVER THE WEEKEND AND
BRUSH THE AREA WITH A CHANCE OF LIGHT SNOW AND LIGHT RAIN. AT THIS
POINT IT APPEARS THE BRUNT OF THE SYSTEM IN THE FORM OF RAINFALL
WILL BE SOUTH OF THE AREA.
&&
.SHORT TERM...(415 PM EST WED FEB 1 2012)
(TONIGHT THROUGH FRIDAY NIGHT)
NOT MUCH IN THE WAY OF CONCERNS THROUGH THE SHORT TERM. MAIN ITEM
WILL BE THE EXTENT OF LOW CLOUDS TONIGHT. DECIDED GIVEN CLIMATOLOGY
TO ROLL WITH LOWER CLOUDS TRYING TO HANG ON. USED A MOSTLY CLOUDY
WORDING THROUGH THE NIGHT FOR NOW. BUFKIT RUC OVERVIEWS SHOW
MOISTURE HANGING ON BETWEEN 2000-3500FT INTO THURSDAY MORNING. THERE
MAY BE SOME EBB AND FLOW TO THE CLOUDS THOUGH AS THERE IS A CLEARING
LINE PRESSING IN FROM THE SOUTHWEST. ENVISION SOME CLEARING THIS
EVENING WITH THE CLOUDS FILLING BACK IN OVERNIGHT.
BEYOND TONIGHT...GENERALLY A PARTLY CLOUDY FORECAST WITH SURFACE
HIGH PRESSURE IN PLACE. COMPLICATING FACTORS THOUGH ARE A SHORTWAVE
DIVING SOUTHEAST ON THURSDAY WHICH MAY INCREASE CLOUD COVER AND
POTENTIALLY SOME LOW CLOUDS FILTERING IN BEHIND THE WAVE THURSDAY
NIGHT AND FRIDAY.
&&
.LONG TERM...(415 PM EST WED FEB 1 2012)
(SATURDAY THROUGH WEDNESDAY)
FORECAST CONCERNS CONTINUE TO BE THE LOW MOVING OUT OF THE SRN
PLAINS OVER THE WEEKEND.
THE GFS REMAINS CONSISTENT IN MOVING THE LOW FROM OKLAHOMA EAST
ACROSS THE OHIO VALLEY. THE NAM IS ON BOARD WITH THIS SOLUTION. THE
ECMWF IS NOW GIVING A NOD TO THE GFS BY DEVELOPING A LOW OVER
KENTUCKY AND THEN SHEARING IT OUT INTO A TROUGH OVER THE
APPALACHIANS. WITH THE ECMWF NOW WEAKENING IT/S LOW OVER IOWA AND
DEVELOPING ONE FARTHER SOUTH...CONFIDENCE IS INCREASING THAT A LOW
WILL MOVE ACROSS THE OHIO VALLEY OVER THE WEEKEND. THIS TRACK
COUPLED WITH FORECAST SOUNDINGS ALSO SUGGESTS THAT ALL THE PCPN WILL
BE SNOW. HOW MUCH PCPN WE SEE IS STILL UP IN THE AIR...SO TO SPEAK.
BOTH THE NAM/GFS SHOW A NICE SLUG OF PCPN BEHIND THE LOW LIKELY
ASSOCIATED WITH DEFORMATION PROCESSES. HIGHEST CHANCES FOR PCPN WILL
BE ALONG/SOUTH OF I-96 SATURDAY AND SUNDAY. MONDAY LOOKS DRY BEFORE
ANOTHER SHORT WAVE MOVING SOUTH ACROSS THE GREAT LAKES BOOSTS PCPN
CHANCES TUESDAY/WEDNESDAY. TEMPS WILL BE MOSTLY ABOVE NORMAL THROUGH
THE PERIOD.
&&
.AVIATION...(1156 PM EST WED FEB 1 2012)
MVFR CEILINGS FROM 1800 TO 2500 FEET AGL WILL CONTINUE OVERNIGHT AS
STRATUS DECK HANGS ON. SOME UNCERTAINTY EXISTS IN THE CLOUD FORECAST
FOR THURSDAY. WILL HAVE TO WATCH IFR CEILING IN LOW STRATUS NOW
ACROSS PARTS OF WISCONSIN TO SEE IF THIS WILL MOVE EAST THURSDAY
MORNING....AND AFFECT WESTERN LOWER MICHIGAN OTHERWISE...THERE COULD
BE SOME IMPROVEMENT TO VFR THURSDAY AS CEILING HEIGHTS LIFT BY
AFTERNOON. WINDS WILL BE LIGHT AND VARIABLE TONIGHT AND GO WEST BUT
REMAIN BELOW 10 KNOTS THURSDAY.
&&
.MARINE...(415 PM EST WED FEB 1 2012)
SURFACE RIDGING WILL BE SITUATED OVER THE GREAT LAKES AREA THE NEXT
36 HOURS OF SO...PROVIDING RELATIVELY TRANQUIL CONDITIONS OUT ON THE
LAKE. WAVES AROUND 1 FOOT ARE EXPECTED INTO FRIDAY WITH WINDS OF 10
KNOTS OR LESS.
&&
.HYDROLOGY...(415 PM EST WED FEB 1 2012)
RAIN IN THE LAST WEEK OR SO...COMBINED WITH SNOWMELT THE LAST COUPLE
OF DAYS HAS LED TO ELEVATED RIVER LEVELS ACROSS THE AREA. THAT
SAID...MOST SITES REMAIN...OR ARE FORECAST TO REMAIN WITHIN BANK.
THE USGS PERCENT OF NORMAL PAGE INDICATES THAT MOST SITES ARE IN
EITHER THE ABOVE NORMAL OR MUCH ABOVE NORMAL CATEGORY. THE KALAMAZOO
RIVER BASIN AND THE UPPER REACHES OF THE GRAND ARE THE HIGHEST. WE
CURRENTLY HAVE RIVER FLOOD ADVISORIES OUT FOR BURLINGTON...VICKSBURG
AND IONIA. THESE SITES ARE NOT PROJECT TO REACH WARNING STATUS. WITH
DRY WEATHER FORECAST THE NEXT COUPLE DAYS...RIVER HEADLINES SHOULD
REMAIN FAIRLY STABLE.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...NONE.
&&
$$
SYNOPSIS: DUKE
SHORT TERM: DUKE
LONG TERM: 93
AVIATION: OSTUNO
MARINE: DUKE
HYDROLOGY: DUKE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1134 PM EST WED FEB 1 2012
.UPDATE...
BAND OF CONVECTIVE SNOW SHOWERS (H8-H7 LAPSE RATES OVR 8.5 C/KM) ARE
PUSHING INTO WESTERN LAKE SUPERIOR AHEAD OF SHORTWAVE. MAIN CHANGE TO
EARLIER FCST UPDATE WAS TO INCLUDE MENTION OF FZG PCPN IN FAR WEST
THROUGH AROUND 09Z. RISK OF MUCH FREEZING PCPN IS SMALL...BUT THERE
WAS A BRIEF PERIOD OF FZRA AT KDLH AND RUC13 SHOWS 925MB TEMPS/WET-
BULB ZERO TEMPS RIGHT AROUND 0C OVR KIWD AT 06Z. DRYING IS VERY
EVIDENT BEHIND THE LINE OF WINTRY PCPN...SO EXPECT JUST A BRIEF
PERIOD OF SNOW AND MAYBE LGT FZRA/FZDZ OVR FAR WEST WITH JUST LGT
SNOW/FLURRIES BY TIME IT REACHES CNTRL CWA TOWARD DAYBREAK THURSDAY.
UPDATED GRIDS TO SHOW THESE TRENDS. TEMPS HAVE FALLEN INTO MID TEENS
ALONG WI BORDER WHERE SKIES CLEARED. IN THOSE AREAS...SHOULD SEE
TEMPS RISE UP THROUGH LATER TONIGHT AS CLOUDS AND SNOW SHOWERS MOVE IN
FM THE WEST. ELSEWHERE... TRENDS IN FCST FOR TEMPS AND SKY LOOK GOOD
FOR NOW. &&
PREV DISCUSSION...ISSUED AT 858 PM EST WED FEB 1 2012...
.SHORT TERM...(THIS EVENING THROUGH THURSDAY)
ISSUED AT 423 PM EST WED FEB 1 2012
LATE THIS AFTERNOON THROUGH EARLY EVENING...MAIN ISSUE WILL BE
CLEARING SKIES NEAR THE WI BORDER. TREND IS EXPECTED TO CONTINUE
THROUGH EARLY EVENING BEFORE COVERAGE INCREASES AGAIN OVERNIGHT.
TEMPERATURE TRENDS WILL NEED TO BE MONITORED OVERNIGHT AS MODEL
GUIDANCE...ESPECIALLY THE NAM...INDICATED TEMPERATURES DROPPING INTO
THE LOWER 20S. LOW TEMPERATURES LATE THIS EVENING WILL BE LARGELY
DEPENDENT UPON THE SKY COVER.
OVERNIGHT TONIGHT THROUGH THURSDAY MORNING...MODELS ARE IN GOOD
AGREEMENT WITH A SHORT WAVE MOVING FROM MINNESOTA INTO WESTERN UPPER
MI AFTER 00Z TONIGHT. AHEAD OF THE SHORTWAVE EXPECT SNOW SHOWERS TO
DEVELOP AND PROGRESS EASTWARD THROUGH THURSDAY MORNING. WHILE THE
SNOW SHOULD REMAIN ON THE LIGHT SIDE...THE AREAS MORE LIKELY TO SEE
LIGHT ACCUMULATION WOULD BE OVER THE KEWEENAW AS THE GFS AND THE NAM
SHOW THE GREATEST FORCING OVER THE CENTRAL GREAT LAKES AS INDICATED
BY OMEGA LOCATED IN THE DGZ. THERE IS A POSSIBILITY THAT SOME
DRIZZLE MAY MOVE AHEAD OF THE SYSTEM...HOWEVER WITH THE WETBULB
TEMPERATURE REMAINING BELOW ZERO AND ABSENCE OF ANY ADVECTION EXPECT
THAT ANY DRIZZLE WOULD BE VERY BRIEF. BY THURSDAY
AFTERNOON...PRECIPITATION SHOULD COME TO AN END AS SHORTWAVE PRESSES
EASTWARD IN THE FAR EASTERN PORTION OF THE U.P. SKY COVER WILL
LINGER AS LOW LEVEL MOISTURE REMAINS IN PLACE.
TEMPERATURES THROUGH THE SHORT TERM PERIOD SHOULD BE ABOVE NORMAL.
.LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY)
ISSUED AT 423 PM EST WED FEB 1 2012
SHORTWAVE SLIDING THROUGH THE AREA ON THURS AFTN WILL BE SHIFTING E
OF THE AREA AT THE START OF THE PERIOD...ALLOWING HIGH PRESSURE TO
START TO BUILD IN TO THE UPPER GREAT LKS THURS NIGHT. BUT...DRY MID
LEVEL AIR FLOWING SE IN THE NW FLOW...ALONG WITH WEAK H875
WAA...WILL KEEP LLVL INVERSION IN PLACE AND SHOULD KEEP LOW CLOUDS
TRAPPED OVER THE AREA ON THURS NIGHT. WITH H900-880 TEMPS AROUND
-8C...THERE MAY BE ENOUGH LK INFLUENCE TO ENHANCE THE CLOUDS...WHICH
COMBINED WITH LIGHT NNW FLOW COULD LEAD TO SOME UPSLOPE --SHSN/DZ
OVER THE HIGHER TERRAIN NEAR LK SUPERIOR. IF ABUNDANT LLVL MOISTURE
ON 12Z NAM AND OUR LOCAL WRF-ARW PANS OUT WILL LIKELY SEE WIDESPREAD
FOG...ESPECIALLY OVER THE HIGHER TERRAIN...SO ADDED A MENTION OF
PATCHY FOG TO THE FCST FOR THURS NIGHT.
HIGH PRESSURE WILL SETTLE INTO THE UPPER GREAT LKS ON FRI FROM WRN
ONTARIO...WHICH WILL WEAKEN THE WINDS FURTHER ACROSS THE AREA. A
SHORTWAVE DROPPING THROUGH THE NW FLOW WILL BRUSH THE AREA DURING
THE DAY...BUT LIMITED MOISTURE ASSOCIATED WITH IT SHOULDN/T LEAD TO
ANY PCPN WITH MID LVL DRY AIR STILL IN PLACE. LOW CLOUDS FROM THURS
NIGHT SHOULD STILL BE COVERING THE AREA FOR MUCH OF FRI...BUT
--SHSN/DZ POTENTIAL LOOKS TO DIMINISH WITH LACK OF UPSLOPE FLOW AND
LLVL DRYING FROM THE SFC HIGH.
DRIER AIR ARRIVES FRI NIGHT AND SAT WITH THE SFC HIGH AND AREA BEING
BETWEEN UPPER LOW ROTATING JUST E OF THE CNTRL ROCKIES AND RIDGE
OVER THE CANADIAN PRAIRIES. OVERALL SUBSIDENCE AND DRY AIR ROTATING
IN FROM CANADA...WHICH LEADS TO A DRY AND CONTINUED WARMER THAN
NORMAL PERIOD. DROPPED LOWS SEVERAL DEGREES ON FRI NIGHT...AS LIGHT
WINDS...CLEAR SKIES...AND PWAT VALUES AROUND 45 PERCENT OF NORMAL
SUPPORTS DECENT RADIATIONAL COOLING.
DAYS 4 THROUGH 7 /SAT NIGHT THROUGH NEXT WEDNESDAY/...
FIRST PART OF THE PERIOD DEPENDS ON THE TRACK OF THE UPPER LOW
EXITING THE CNTRL PLAINS AND ASSOCIATED SFC FEATURES. STILL
DIFFERING OPINIONS IN THE DETERMINISTIC AND ENS MEMBERS ON THE
HANDLING OF THIS FEATURE. MOST HAVE THE IDEA OF THE UPPER LOW
SHIFTING EAST SAT NIGHT INTO SUN NIGHT AND THROUGH THE LOWER GREAT
LKS...BUT AS IS NORMALLY THE CASE WITH THESE TYPES OF SYSTEMS...THE
EXACT TIMING/LOCATION REMAINS TO BE SEEN. LARGE SPREAD IN THE
ENSEMBLE MEMBERS TOO...SO DON/T HAVE A WHOLE LOT OF CONFIDENCE IN
EXACT FEATURES AND WILL FOLLOW A CONSENSUS FOR THE FORECAST.
THUS...HAVE A DRY FCST ACROSS THE CWA FOR THE SECOND HALF OF THE
WEEKEND AND PARTLY TO MOSTLY CLEAR SKIES...ALTHOUGH THE SRN HALF OF
THE CWA MAY END UP SEEING MORE SCT/BKN MID-HIGH CLOUDS AS MAIN AREA
OF SYSTEM PUSHES S OF THE AREA.
GFS/ECMWF SHOWING COLDER H850 TEMPS SURGING IN TUES BEHIND A COLD
FRONT DROPPING THROUGH THE AREA ON MON NIGHT. COLD FRONT LOOKS TO
HAVE LIMITED MOISTURE ASSOCIATED WITH IT...WHICH IS ALSO THE CASE
BEHIND IT. THIS WILL BRING COLDER H850 AIR...TOWARDS -16C...AND
CHANCES OF LES TO NNW WIND FAVORED LOCATIONS AND BUMPED UP POPS SOME
IN THOSE AREAS TUES AND TUES NIGHT. WITH LIMITED MOISTURE...WILL
KEEP TUES NIGHT INTO WED DRY AS WINDS BACK TO THE W .
&&
.AVIATION /FOR THE 00Z TAF ISSUANCE/...
COMPLICATED FORECAST THIS PERIOD AS LOW CLOUDS HAVE SLOWLY ERODED AT
IWD. WINDS BACKING TO THE SW BEHIND HIGH PRESSURE MAY ADVECT IFR
CEILINGS BACK BY 04Z. THERE IS ALSO A SLIGHT CONCERN THAT SOME FG
COULD DEVELOP BEFORE CLOUDS RETURN...THROUGH CONFIDENCE IS VERY LOW.
IFR CIGS SHOULD REMAIN AT BOTH CMX AND SAW AS DIURNAL DISRUPTION OF
CLOUD DECK APPEARS TO BE SLOWING TO THE SOUTH. THEN A WEAK SYSTEM
WILL BRING -SHSN INTO IWD AND CMX AFTER MIDNIGHT...AND INTO SAW AFTER
12Z. IFR CIGS WILL REMAIN THE ISSUE DURING THE -SHSN AS VIS IMPACTS
WILL BE MINIMAL. WINDS THEN VEER TO A GENERAL WESTERLY DIRECTION
TOMORROW. CIGS WILL REMAIN LOW AT ALL SITES...AND EVEN DROP SLIGHTLY
BELOW IFR LEVELS AT CMX IN THE MORNING DUE TO TERRAIN ENHANCEMENT
BEFORE HEATING BRINGS LEVELS BACK TO IFR RANGE.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 423 PM EST WED FEB 1 2012
IN THE SHORT TERM...WIND AND WAVES SHOULD REMAIN FAIRLY LIGHT OVER
THE LAKE AS PRESSURE GRADIENT REMAINS RELAXED. THE NEXT CHANCE OF
INCREASED WINDS WILL MOVE INTO THE AREA LATE MONDAY AND TUESDAY AS
PRESSURE GRADIENT TIGHTENS BETWEEN AND AREA OF HIGH PRESSURE LOCATED
OVER THE NORTHERN PLAINS AND A LOW PRESSURE CENTERED OVER THE MID
ATLANTIC STATES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...JLA
SHORT TERM...KEC
LONG TERM...SRF
AVIATION...TK
MARINE...KEC
AREA FORECAST DISCUSSION
NWS BUFFALO NY
427 AM EST THU FEB 2 2012
.SYNOPSIS...
WEAK HIGH PRESSURE OVER THE REGION WILL TRAP LOW LEVEL MOISTURE AND
KEEP ABUNDANT CLOUD COVER OVER THE AREA THROUGH TONIGHT...WITH
NOTHING MORE THAN A FEW FLURRIES ACROSS THE HIGHER TERRAIN OF
WESTERN NEW YORK. MORE SUNSHINE IS EXPECTED FOR THE WEEKEND.
TEMPERATURES WILL REMAIN JUST ABOVE NORMAL EARLY FEBRUARY READINGS
WITH 30S FOUND ACROSS MUCH OF THE REGION THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
07Z SURFACE ANALYSIS SHOWED A WEAK HIGH RIDGED FROM JAMES BAY DOWN
ACROSS THE WESTERN GREAT LAKES. THIS HIGH WILL BUILD EASTWARD TODAY
WITH THE RIDGE AXIS EVENTUALLY SETTLING ACROSS THE AREA TONIGHT.
THE PRIMARY FORECAST CONCERN WILL BE WITH THE WIDESPREAD STRATUS
DECK CURRENTLY IN PLACE OVER THE AREA. NORTHERLY COMPONENT IN
PLACE TODAY WILL BE FAVORABLE IN KEEPING CLOUD COVER IN
PLACE...ESPECIALLY ACROSS THE FAVORED UPSLOPE AREAS OF THE WESTERN
SOUTHERN TIER. LATEST RUC MODEL SOUNDINGS AGREE WITH THIS THINKING
AS IT KEEPS LOW LEVEL MOISTURE VALUES QUITE HIGH IN THE LOWEST 3
THOUSAND FEET. WEAK SHORTWAVE PUSHING THROUGH THE UPPER LAKES WILL
PASS ACROSS THE REGION TODAY AND COULD BRING THE POTENTIAL FOR
SOME FLURRIES TO THE WESTERN SOUTHERN TIER AND GENESEE VALLEY. WEAK
COLD AIR ADVECTION AND CLOUD COVER SHOULD KEEP TEMPERATURES PRETTY
MUCH STEADY THROUGH THE DAY AND NOT VARYING MUCH FROM CURRENT
READINGS IN THE LOWER TO MID 30S....BUT UPPER 20S FOR PORTIONS OF
THE NORTH COUNTRY.
RIDGE AXIS ACROSS THE AREA TONIGHT ALONG WITH SOME DRYING BEHIND THE
SHORTWAVE AND BACKING WINDS COULD BRING A BETTER OPPORTUNITY FOR
SOME CLEARING... BUT BASED ON AMOUNT OF UPSTREAM CLOUD CLOUD WILL
NOT BE TOO OPTIMISTIC. OVERNIGHT TEMPERATURES WILL DEPEND GREATLY
ON AMOUNT OF CLEARING IF ANY...WITH MID TO UPPER 20S FOR MOST OF
THE AREA...WITH TEENS ACROSS THE NORTH COUNTRY WITH A BETTER
CHANCE TO SEE ADEQUATE CLEARING.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
THE PERIOD WILL BE RATHER QUIET...AS A BROAD AREA OF HIGH
PRESSURE AT THE SURFACE WILL REMAIN ACROSS THE REGION THROUGH THE
PERIOD. THIS WILL KEEP COLD AIR CUT OFF TO THE NORTH...WITH
TEMPERATURES EXPECTED TO REMAIN ABOVE NORMAL THROUGH THE PERIOD.
THE NEXT SHORTWAVE WILL APPROACH ON FRIDAY WITH A WEAK COLD FRONT
GRAZING THE REGION FRIDAY EVENING AND NIGHT. WILL HAVE CHANCE POPS
FOR FRIDAY MORNING AND AFTERNOON BUT ONLY CARRY PRECIP TYPE AS
FLURRIES AS WILL NOT EXPECT ACCUMULATION...THEN STILL CHANCE POPS
BUT LIGHT SNOW SHOWERS WITH A MINOR ACCUMULATION POSSIBLE. MOISTURE
PROFILE IS MEAGER IN THE MID LEVELS WITH LITTLE IN THE WAY OF
CRYSTAL GROWTH AVAILABLE ALOFT...SOME PRECIP MAY BE AS LIGHT DRIZZLE
DURING THE DAY ON FRIDAY...BUT THERE ARE INDICATIONS ON NAM12 BUFKIT
OF CRYSTAL GROWTH ALOFT DURING LATE AFTERNOON AND EVENING LEADING TO
FLURRIES OR LIGHT SNOW VERSUS DRIZZLE.
TEMPERATURES WILL REMAIN ON THE WARM SIDE FOR THIS TIME OF
YEAR...WITH FRIDAY LIKELY TO RISE INTO THE MID TO UPPER 30S IN MOST
LOCATIONS...LOWER 30S EAST OF LAKE ONTARIO. CLOUDS ASSOCIATED WITH
THE PASSAGE OF THE WEAK COLD FRONT AND SOME LAKE INDUCED CLOUDINESS
WILL KEEP TEMPS UP INITIALLY DURING FRIDAY NIGHT...BUT DRYING AND
CLEARING AFTER MIDNIGHT SHOULD ALLOW TEMPS TO FALL TO THE LOWER 20S
FOR MUCH OF THE FORECAST AREA AND EVEN TO THE LOWER TEENS EAST OF
LAKE ONTARIO.
WEST TO EAST SURFACE RIDGE OF HIGH PRESSURE WILL COVER THE AREA FOR
THE WEEKEND WITH COOLER TEMPS ON SATURDAY IN THE LOWER TO MID 20S
EAST OF LAKE ONTARIO TO LOWER 30S ELSEWHERE...AND THE UPPER 20S TO
MID 30S ON SUNDAY. EXPECT A SLIGHT CHANCE OF FLURRIES SUNDAY AS A
MOISTURE STARVED WAVE DROPS SOUTH THROUGH THE BLOCKED FLOW.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
IT WILL BE A FAIRLY QUIET PATTERN THROUGH EARLY NEXT WEEK. THE MAIN
FORECAST CHALLENGE WILL BE TIMING THE EXIT OF A CUT-OFF 500 MB
LOW...WHICH BOTH GFS AND ECMWF MAINTAIN ACROSS THE MIDWESTERN STATES
/NEAR IOWA/ THROUGH AT LEAST 12Z MONDAY. THE 500MB CLOSED LOW WILL
KEEP A BLOCKED FLOW AND EFFECTIVELY PREVENT ANY SIGNIFICANT WEATHER
MAKERS FROM CROSSING OUR AREA. THE LOW IS NOT FORECAST TO OPEN AND
ENTER THE NORTHERN STREAM UNTIL LATER ON MONDAY NIGHT. MONDAY SHOULD
REMAIN FREE OF PRECIP WITH TEMPS CONTINUING TO MODERATE INTO THE
MID/UPR 30S EAST OF LAKE ONTARIO TO THE LOWER 40S ELSEWHERE...THANKS
TO THE RIDGING DOWNSTREAM OF THE MIDWESTERN CLOSED LOW.
THE CLOSED LOW WILL FILL AND MERGE WITH A MUCH HIGHER AMPLITUDE
TROUGH OVER EASTERN CANADA...BRINGING A CHANCE OF SNOW TO THE REGION
ON TUESDAY AND TUESDAY NIGHT AS COLD FRONT CROSSES THE AREA. GFS AND
ECMWF ARE DROPPING A COLD POOL ACROSS QUEBEC AND NORTHERN NY...BUT
THE VERY COLDEST AIR WILL STAY WELL NORTH THEN EAST OF OUR REGION.
BOTH MODELS ALSO PUSH A SURFACE RIDGE ACROSS THE EASTERN GREAT LAKES
AND THE FULL LENGTH OF THE SAINT LAWRENCE RIVER TUESDAY NIGHT...
FOLLOWED QUICKLY BY THE PACIFIC ORIGIN HIGH PRESSURE CENTER ON
WEDNESDAY...THUS ENDING THE CHANCE OF SNOW. AFTER THE MILD START OF
THE WEEK...EXPECT TEMPS TO FALL BACK TO LOWS IN THE UPPER SINGLE
NUMBERS AND TEENS TUESDAY NIGHT WITH HIGHS IN THE MID 20S TO LOWER 30S
DURING WEDNESDAY...NEARLY NORMAL FOR EARLY FEBRUARY.
&&
.AVIATION /10Z THURSDAY THROUGH MONDAY/...
WIDESPREAD MVFR CIGS CONTINUING EARLY THIS MORNING. REGIONAL
OBSERVATIONS SUGGESTING CIGS WILL REMAIN BETWEEN 2K AND 25 HUNDRED
FEET THROUGH AT LEAST 15Z. MODEL SOUNDINGS SUGGESTING LOW LEVEL
MOISTURE MAY BE ABLE TO MIX OUT BY AFTERNOON...BUT LIKELY HOLDING
IN ALONG THE WESTERN SOUTHERN TIER IN A NORTHERLY UPSLOPE FLOW.
LOW LEVEL MOISTURE REMAINING IN PLACE TONIGHT AND AREAS WHICH
IMPROVE TO VFR MAY HAVE CIGS RETURN BACK DOWN TO MVFR.
OUTLOOK...
FRIDAY...MAINLY VFR
FRIDAY NIGHT...MVFR CIGS WITH A CHC FOR PRECIPITATION EAST OF
LAKE ONTARIO.
SATURDAY THROUGH MONDAY...MAINLY VFR.
&&
.MARINE...
HIGH PRESSURE OVER THE CENTRAL GREAT LAKES WILL BUILD EASTWARD TODAY
WITH THE RIDGE AXIS ACROSS THE EASTERN GREAT LAKES TONIGHT. THE
PRESSURE GRADIENT HAS ALREADY WEAKENED SUBSTANTIALLY EARLY THIS
MORNING. WINDS AND WAVE WILL CONTINUE TO DECREASE TODAY AS THE RIDGE
AXIS DRAWS CLOSER. THIS HIGH PRESSURE SYSTEM WILL PRODUCE FAVORABLE
MARINE CONDITIONS INTO THE WEEKEND WITH NO FLAGS EXPECTED.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TMA
NEAR TERM...TMA
SHORT TERM...WCH
LONG TERM...WCH
AVIATION...TMA
MARINE...TMA
AREA FORECAST DISCUSSION
NWS BUFFALO NY
317 AM EST THU FEB 2 2012
.SYNOPSIS...
WEAK HIGH PRESSURE OVER THE REGION WILL TRAP LOW LEVEL MOISTURE AND
KEEP ABUNDANT CLOUD COVER OVER THE AREA THROUGH TONIGHT...WITH
NOTHING MORE THAN A FEW FLURRIES ACROSS THE HIGHER TERRAIN OF
WESTERN NEW YORK. MORE SUNSHINE IS EXPECTED FOR THE WEEKEND.
TEMPERATURES WILL REMAIN JUST ABOVE NORMAL EARLY FEBRUARY READINGS
WITH 30S FOUND ACROSS MUCH OF THE REGION THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
07Z SURFACE ANALYSIS SHOWED A WEAK HIGH RIDGED FROM JAMES BAY DOWN
ACROSS THE WESTERN GREAT LAKES. THIS HIGH WILL BUILD EASTWARD TODAY
WITH THE RIDGE AXIS EVENTUALLY SETTLING ACROSS THE AREA TONIGHT.
THE PRIMARY FORECAST CONCERN WILL BE WITH THE WIDESPREAD STRATUS
DECK CURRENTLY IN PLACE OVER THE AREA. NORTHERLY COMPONENT IN
PLACE TODAY WILL BE FAVORABLE IN KEEPING CLOUD COVER IN
PLACE...ESPECIALLY ACROSS THE FAVORED UPSLOPE AREAS OF THE WESTERN
SOUTHERN TIER. LATEST RUC MODEL SOUNDINGS AGREE WITH THIS THINKING
AS IT KEEPS LOW LEVEL MOISTURE VALUES QUITE HIGH IN THE LOWEST 3
THOUSAND FEET. WEAK SHORTWAVE PUSHING THROUGH THE UPPER LAKES WILL
PASS ACROSS THE REGION TODAY AND COULD BRING THE POTENTIAL FOR
SOME FLURRIES TO THE WESTERN SOUTHERN TIER AND GENESEE VALLEY. WEAK
COLD AIR ADVECTION AND CLOUD COVER SHOULD KEEP TEMPERATURES PRETTY
MUCH STEADY THROUGH THE DAY AND NOT VARYING MUCH FROM CURRENT
READINGS IN THE LOWER TO MID 30S....BUT UPPER 20S FOR PORTIONS OF
THE NORTH COUNTRY.
RIDGE AXIS ACROSS THE AREA TONIGHT ALONG WITH SOME DRYING BEHIND THE
SHORTWAVE AND VEERING WINDS COULD BRING A BETTER OPPORTUNITY FOR
SOME CLEARING... BUT BASED ON AMOUNT OF UPSTREAM CLOUD CLOUD WILL
NOT BE TOO OPTIMISTIC. OVERNIGHT TEMPERATURES WILL DEPEND GREATLY
ON AMOUNT OF CLEARING IF ANY...WITH MID TO UPPER 20S FOR MOST OF
THE AREA...WITH TEENS ACROSS THE NORTH COUNTRY WITH A BETTER
CHANCE TO SEE ADEQUATE CLEARING.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
THE PERIOD WILL BE RATHER QUIET...AS A BROAD AREA OF HIGH
PRESSURE AT THE SURFACE WILL REMAIN ACROSS THE REGION THROUGH THE
PERIOD. THIS WILL KEEP COLD AIR CUT OFF TO THE NORTH...WITH
TEMPERATURES EXPECTED TO REMAIN ABOVE NORMAL THROUGH THE PERIOD.
THE NEXT SHORTWAVE WILL APPROACH ON FRIDAY WITH A WEAK COLD FRONT
GRAZING THE REGION FRIDAY EVENING AND NIGHT. WILL HAVE CHANCE POPS
FOR FRIDAY MORNING AND AFTERNOON BUT ONLY CARRY PRECIP TYPE AS
FLURRIES AS WILL NOT EXPECT ACCUMULATION...THEN STILL CHANCE POPS
BUT LIGHT SNOW SHOWERS WITH A MINOR ACCUMULATION POSSIBLE. MOISTURE
PROFILE IS MEAGER IN THE MID LEVELS WITH LITTLE IN THE WAY OF
CRYSTAL GROWTH AVAILABLE ALOFT...SOME PRECIP MAY BE AS LIGHT DRIZZLE
DURING THE DAY ON FRIDAY...BUT THERE ARE INDICATIONS ON NAM12 BUFKIT
OF CRYSTAL GROWTH ALOFT DURING LATE AFTERNOON AND EVENING LEADING TO
FLURRIES OR LIGHT SNOW VERSUS DRIZZLE.
TEMPERATURES WILL REMAIN ON THE WARM SIDE FOR THIS TIME OF
YEAR...WITH FRIDAY LIKELY TO RISE INTO THE MID TO UPPER 30S IN MOST
LOCATIONS...LOWER 30S EAST OF LAKE ONTARIO. CLOUDS ASSOCIATED WITH
THE PASSAGE OF THE WEAK COLD FRONT AND SOME LAKE INDUCED CLOUDINESS
WILL KEEP TEMPS UP INITIALLY DURING FRIDAY NIGHT...BUT DRYING AND
CLEARING AFTER MIDNIGHT SHOULD ALLOW TEMPS TO FALL TO THE LOWER 20S
FOR MUCH OF THE FORECAST AREA AND EVEN TO THE LOWER TEENS EAST OF
LAKE ONTARIO.
WEST TO EAST SURFACE RIDGE OF HIGH PRESSURE WILL COVER THE AREA FOR
THE WEEKEND WITH COOLER TEMPS ON SATURDAY IN THE LOWER TO MID 20S
EAST OF LAKE ONTARIO TO LOWER 30S ELSEWHERE...AND THE UPPER 20S TO
MID 30S ON SUNDAY. EXPECT A SLIGHT CHANCE OF FLURRIES SUNDAY AS A
MOISTURE STARVED WAVE DROPS SOUTH THROUGH THE BLOCKED FLOW.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
IT WILL BE A FAIRLY QUIET PATTERN THROUGH EARLY NEXT WEEK. THE MAIN
FORECAST CHALLENGE WILL BE TIMING THE EXIT OF A CUT-OFF 500 MB
LOW...WHICH BOTH GFS AND ECMWF MAINTAIN ACROSS THE MIDWESTERN STATES
/NEAR IOWA/ THROUGH AT LEAST 12Z MONDAY. THE 500MB CLOSED LOW WILL
KEEP A BLOCKED FLOW AND EFFECTIVELY PREVENT ANY SIGNIFICANT WEATHER
MAKERS FROM CROSSING OUR AREA. THE LOW IS NOT FORECAST TO OPEN AND
ENTER THE NORTHERN STREAM UNTIL LATER ON MONDAY NIGHT. MONDAY SHOULD
REMAIN FREE OF PRECIP WITH TEMPS CONTINUING TO MODERATE INTO THE
MID/UPR 30S EAST OF LAKE ONTARIO TO THE LOWER 40S ELSEWHERE...THANKS
TO THE RIDGING DOWNSTREAM OF THE MIDWESTERN CLOSED LOW.
THE CLOSED LOW WILL FILL AND MERGE WITH A MUCH HIGHER AMPLITUDE
TROUGH OVER EASTERN CANADA...BRINGING A CHANCE OF SNOW TO THE REGION
ON TUESDAY AND TUESDAY NIGHT AS COLD FRONT CROSSES THE AREA. GFS AND
ECMWF ARE DROPPING A COLD POOL ACROSS QUEBEC AND NORTHERN NY...BUT
THE VERY COLDEST AIR WILL STAY WELL NORTH THEN EAST OF OUR REGION.
BOTH MODELS ALSO PUSH A SURFACE RIDGE ACROSS THE EASTERN GREAT LAKES
AND THE FULL LENGTH OF THE SAINT LAWRENCE RIVER TUESDAY NIGHT...
FOLLOWED QUICKLY BY THE PACIFIC ORIGIN HIGH PRESSURE CENTER ON
WEDNESDAY...THUS ENDING THE CHANCE OF SNOW. AFTER THE MILD START OF
THE WEEK...EXPECT TEMPS TO FALL BACK TO LOWS IN THE UPPER SINGLE
NUMBERS AND TEENS TUESDAY NIGHT WITH HIGHS IN THE MID 20S TO LOWER 30S
DURING WEDNESDAY...NEARLY NORMAL FOR EARLY FEBRUARY.
&&
.AVIATION /08Z THURSDAY THROUGH MONDAY/...
MAINLY MVFR CIGS CONTINUE TONIGHT...WITH DROP TO IFR POSSIBLE AFTER
09Z. KART AT VFR AND MAY REMAIN THERE. INFRARED SATELLITE IMAGERY
SHOWS EXTENSIVE CLOUD COVER ACROSS THE FORECAST AREA. 03Z LAMP
GUIDANCE CONTINUES TO SHOW THE TREND SHOULD CONTINUE THROUGH THE
NIGHT. WEST WINDS EXPECTED TO VEER TO NORTHERLY WHICH TYPICALLY
HELPS CLOUDS TO HANG IN PLACE. THEN WINDS VEER A BIT MORE TO
NORTHEASTERLY LATE TONIGHT. A NORTHEASTERLY FLOW CLIMATOLOGICALLY
YIELDS IFR CIGS FOR KBUF/KIAG/KROC SITES. LOWERED CIGS IN FORECAST
TO IFR BASED ON THIS. OBS CONTINUE TO REMAIN OUT OF SERVICE AT KJHW
UFN. GUIDANCE SHOWS TREND AT KJHW TO OTHER WESTERN NY TAFS. KART
WILL HAVE TO BE WATCHED FOR ADJUSTMENT. LOWER CONFIDENCE OF MVFR
THERE WITH N/NE WINDS.
OUTLOOK...
WEDNESDAY NIGHT MAINLY VFR...WITH RAIN/SNOW SHOWERS EAST OF LAKE
ONTARIO.
THURSDAY MAINLY VFR
FRIDAY NIGHT...MVFR CIGS WITH A CHC FOR PRECIPITATION EAST OF LAKE
ONTARIO.
SATURDAY THROUGH MONDAY...MAINLY VFR.
&&
.MARINE...
HIGH PRESSURE OVER THE CENTRAL GREAT LAKES WILL BUILD EASTWARD TODAY
WITH THE RIDGE AXIS ACROSS THE EASTERN GREAT LAKES TONIGHT. THE
PRESSURE GRADIENT HAS ALREADY WEAKENED SUBSTANTIALLY EARLY THIS
MORNING. WINDS AND WAVE WILL CONTINUE TO DECREASE TODAY AS THE RIDGE
AXIS DRAWS CLOSER. THIS HIGH PRESSURE SYSTEM WILL PRODUCE FAVORABLE
MARINE CONDITIONS INTO THE WEEKEND WITH NO FLAGS EXPECTED.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TMA
NEAR TERM...TMA
SHORT TERM...WCH
LONG TERM...WCH
AVIATION...TMA
MARINE...TMA
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1246 AM EST THU FEB 2 2012
.SYNOPSIS...
COLD FRONT WITH A LOW PRESSURE WAVE TONIGHT. HIGH PRESSURE THURSDAY
THROUGH FRIDAY. LOW PRESSURE MOVES INTO THE MISSISSIPPI VALLEY
FRIDAY NIGHT...BUT QUESTIONABLE HOW QUICKLY IT MOVES EAST.
&&
.NEAR TERM /THROUGH TODAY/...
UPDATE...
LOSING SOME OF THE ENHANCEMENT TO THE ECHOES ON RADAR...AND WHILE
STILL CARRYING THUNDER CHANCES...FEEL THUNDER WILL BE ISOLATED
OVER THE NEXT FEW HOURS. RUC DATA DEPICTS THE AXIS OF THE SHORT
WAVE TROUGH ALOFT NOW EAST OF THE MISSISSIPPI RIVER...WHILE THE
SURFACE LOW RESIDES OVER THE MOUNTAINS WITH THE COLD FRONT
TRAILING TO THE WEST SOUTH OF THE OHIO RIVER. ONCE THESE SHOWERS
PASS THROUGH...SHOULD FIND SOME DRYING IN ITS WAKE WITH SOME
DRIZZLE LEFT OVER EARLY THURSDAY.
PREVIOUS DISCUSSION...
THE STRONG GRADIENT IN MOISTURE WILL LINGER IN OUR CWA THROUGH
THE OVERNIGHT.
IN THE EARLY AFTERNOON FINE TUNING OF THE HOURLY GRIDS...STILL TRIED
TO PUSH THE DEEPER MOISTURE BACK NORTH THIS EVENING. SOME OF THE
NEAR TERM MODELS...SUCH AS OUR WRF-NMM TRY TO DISCONNECT THE BAND
FORMING THIS EVENING SOUTH OF THE SURFACE FRONT...WITH THAT DEEPER
MOISTURE ALREADY IN PLACE OVER SOUTHWEST VIRGINIA AND EASTERN
TENNESSEE. LIKE THE IDEA OF ANOTHER MOISTURE MAXIMUM REFORMING JUST
SOUTH OF THE SURFACE FRONT...SO INCREASE POPS HTS-CRW-EKN DURING THE
01Z-04Z INTERVAL...THEN EXITING THE CENTRAL WV MOUNTAINS AROUND 12Z
THURSDAY. WILL ALSO GO WITH LIGHT RAIN AND DRIZZLE FOR THE
LINGERING PCPN THURSDAY MORNING.
CLOUD COVERAGE ON THURSDAY QUESTIONABLE...BUT WAS SLOWER LIFTING THE
CLOUDS OVER THE SNOWSHOE TO BECKLEY REGION DURING THE MORNING.
HAVE NOT FINALIZED TEMPERATURES YET...BUT EXPECT TO GENERATE EVEN A
STRONGER NORTH TO SOUTH GRADIENT FOR MINIMUM TEMPERATURES...BY
RAISING THE MINIMUM TEMPERATURES A DEGREE OR TWO ACROSS THE COAL
FIELDS AND SOUTHWEST VIRGINIA.
CONCERNING THE BIG DAY...GROUNDHOG DAY...SINCE OUR LOCAL WV
GROUNDHOG SLEEPS IN UNTIL 15Z THURSDAY...AND ACTUALLY OBSERVES THE
OVERHEAD SKY...THE CLEARING PROCESS MAY BE UNDERWAY...WITH THE
CLOUDS LIFTING AND THINNING. HOWEVER...STILL HAD LOTS OF CLOUDS AT
THE WILDLIFE CENTER AT 15Z.
&&
.SHORT TERM /TONIGHT THROUGH SATURDAY/...
LOW AND FRONT EXIT TO THE EAST THURSDAY MORNING...TAKING THE PRECIP
WITH IT. HIGH PRESSURE BUILDS IN FROM THE WEST THAT LASTS THROUGH
FRIDAY. VERY LITTLE WRAPAROUND BEHIND THIS SYSTEM IN THE ZONAL FLOW
ALOFT FOR POST FRONTAL SHOWERS...WITH STRONG ANTICYCLONIC FLOW
AROUND BUILDING HIGH PRESSURE. NO REALLY COLD AIR BEHIND THE SYSTEM
FOR THE PRECIP TO END IN ANY WINTRY FORM...COMPLIMENTS OF HIGH
PRESSURE...IN PART...OF PACIFIC ORIGIN. ALSO...NOT ONLY HAVE PRECIP
ENDING EARLY THURSDAY...BUT CLEARING NOT FAR BEHIND. HIGH PRESSURE
WITH SUNSHINE AND ABOVE NORMAL TEMPERATURES FOR THE END OF THE WORK
WEEK. LOOK FOR TEMPS TO STILL BE ABOVE NORMAL FOR THE END OF THE
WORKWEEK.
BIG MODEL DISCREPANCIES CONTINUE FOR THE WEEKEND SYSTEM...SO WILL
LEAVE THAT ALONE FOR NOW.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
STILL CONTINUES TO BE LOTS OF UNCERTAINTY IN THE LONG TERM WITH
LITTLE MODEL AGREEMENT. GFS STILL INDICATES A SIMILAR PATTERN TO
PREVIOUS RUNS WITH LOW PRESSURE AND ASSOCIATED WARM FRONT PUSHING
INTO THE AREA ON SATURDAY...BEFORE SLIDING OFF TO THE EAST SUNDAY AS
A CLOSED LOW TO THE WEST OPENS UP INTO A WAVE...AND THE RESULTING
UPPER TROUGH PUSHES EAST THROUGH THE AREA ON SUNDAY. CANADIAN AND
ECMWF ARE TRYING TO SHOW A SOMEWHAT SIMILAR PATTERN WITH THE LOW
OPENING INTO A WAVE AND A TROUGH PUSHING EAST THROUGH THE AREA...BUT
THEY ARE NOT AS PROGRESSIVE AS THE GFS. DID ELECT TO CONTINUE THE
FORECAST OF BROAD BRUSH OF POPS OVER THE REMAINDER OF THE WEEKEND
INTO EARLY/MID NEXT WEEK WHEN HIGH PRESSURE FINALLY TRIES TO BUILD
INTO THE AREA. THE GOOD NEWS IS...TEMPS SHOULD OVERALL REMAIN WARM
ENOUGH FOR BULK OF PRECIPITATION TO BE IN THE FORM OF RAIN DURING
THE PERIOD. BEST CHANCE FOR ANY RAIN/SNOW OR SNOW SHOWERS WILL BE
AFTER PASSAGE OF TROUGH WHEN COOLER AIR IS ABLE TO FILTER IN. BUT
EVEN THIS REMAINS UNCERTAIN AS ATMOSPHERE MAY DRY OUT BEFORE ENOUGH
COLD AIR IS IN PLACE.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
CB STILL NEEDED OVER THE TRI STATE AREA...CRW AND BKW OVER THE
NEXT FEW HOURS WITH WEAK LINGERING INSTABILITY WITH THIS LINE OF
SHOWERS MOVING IN. SOUTHERN MOUNTAINS CEILINGS TO BE IFR TO LIFR
THROUGH MID MORNING BEFORE A GRADUAL RECOVERY TAKES PLACE.
CEILINGS ELSEWHERE MAINLY TO BE MVFR OR BETTER LESS A COUPLE HOURS
AT HTS WHERE IFR IS OCCURRING...BUT THINK FLUCTUATIONS THERE ARE
LIKELY AND HAVE ADDED A TEMPO GROUP TO COVER THIS. DESPITE
CLOUDS...SOME MIST AND FOG DEVELOPMENT COULD CREATE IFR
VISIBILITIES AT EKN AND CKB THROUGH THE REMAINDER OF THE OVERNIGHT
PERIOD WITH IMPROVEMENT EXPECTED AFTER SUNRISE.
VFR EXPECTED FOR THE LOWLANDS AFTER LOW LEVEL MOISTURE DISSOLVES.
THIS MOISTURE WILL GET HUNG UP IN THE MOUNTAINS...AND CARRY
RESTRICTIONS AT BKW AND EKN LATER THROUGH THE DAY THURSDAY.
CLEARING EXPECTED BY 00Z IN THESE AREAS...AND MOUNTAIN VALLEYS
COULD BE PRONE TO FOG DEVELOPMENT THURSDAY NIGHT.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z FRIDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: MAY SEE IFR VISIBILITIES AT CRW AND PKB.
FLUCTUATIONS IN THE OBSERVATIONS LIKELY AS SHOWERS MOVE THROUGH.
CB MAY NOT MATERIALIZE AT CRW AND BKW.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE THU 02/02/12
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EST 1HRLY 01 02 03 04 05 06 07 08 09 10 11 12
CRW CONSISTENCY M M M M M M M L L L M H
HTS CONSISTENCY H H M M H M L H H H H H
BKW CONSISTENCY M M L L M M M L H H M M
EKN CONSISTENCY M M M M M M M L M M H H
PKB CONSISTENCY H H H H H H H H H H H H
CKB CONSISTENCY M L M M L L L L L H H H
AFTER 06Z FRIDAY...
LOCAL IFR POSSIBLE IN WV VALLEY FOG DAWN FRIDAY. POSSIBLE IFR IN
RAIN SUNDAY INTO MONDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...NONE.
OH...NONE.
KY...NONE.
VA...NONE.
&&
$$
SYNOPSIS...KTB
NEAR TERM...KTB/26
SHORT TERM...JMV
LONG TERM...SL
AVIATION...26
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1127 PM CST WED FEB 1 2012
.AVIATION...
LOW CIGS AND FOG ARE DEVELOPING ACROSS THE AREA TONIGHT MAINLY
INLAND. KGLS AND KLBX ARE BEING INFLUENCED BY EARLIER
PRECIPITATION AND THE FOG WILL BE LATE TO DEVELOP IN THESE AREAS.
MOISTURE IS IN THE AREA AND RAINS FROM TODAY REMAIN ON THE GROUND
SO DENSE FOG IS LIKELY TO DEVELOP BEFORE SUNRISE IN THESE AREAS.
OVER THE REMAINDER OF THE AREA IFR CIGS AND SOME AREAS OF DENSE
FOG HAVE DEVELOPED AND WILL CONTINUE TO DEVELOP DURING THE NIGHT
AND BECOME WIDESPREAD LIFR CIGS AND VSBY. CONDITIONS WILL BE SLOW
TO IMPROVE IN THE AM WITH CONDITIONS NOT BECOMING VFR UNTIL AFTER
18Z ACROSS MOST OF THE AREA. LOW CIGS AND LOW VSBY WILL RETURN
TONIGHT AROUND 02Z-04Z BECOMING WIDESPREAD LIFR BY 06Z.
&&
.PREV DISCUSSION... /ISSUED 807 PM CST WED FEB 1 2012/
DISCUSSION...
HAVE PARED BACK POPS FOR THE NIGHT EXCEPT OVER THE NORTH CLOSER TO
THE BOUNDARY. RUC AND 18Z NAM BOTH TRY TO DEVELOP A THIN BAND OF
PRECIP SOUTH OF THE BOUNDARY BENEATH THE JET STREAK MOVING INTO
LA. WILL CARRY 20S NORTH AFTER MIDNIGHT FOR THIS FOR NOW AND
20/30S OVER THE COASTAL WATERS.
FOG SHOULD RETURN TO THE AREA TONIGHT AND HAVE ISSUED A DENSE FOG
ADVISORY FOR SETX AND COASTAL WATERS. T/TD SPREADS 2-5 DEGREES WITH
DEWPOINTS IN THE 60S...70 SOUTHWEST. WITH THE WET GROUND...CALM
WINDS/LIGHT SOUTH WINDS/SKIES THAT HAVE AT LEAST PARTIAL CLEARED
EXPECT THE T/TD GAPS TO CLOSE QUICKLY WITH LARGE AREAS OF FOG
DEVELOPING AND BECOMING DENSE. A WARM DAY ON TAP TOMORROW WITH
LIGHT SOUTHEASTERLY FLOW SHOULD LEAD TO TEMPERATURES WARMING AFTER
8 AM AND THE FOG DISSIPATING. DO HAVE SOME CONCERNS THAT WITH THE
MORE STABLE AIRMASS OVER THE COASTAL AREAS THE DENSE FOG MAY LAST
BEYOND 9 AM.
45
PREV DISCUSSION... /ISSUED 528 PM CST WED FEB 1 2012/
AVIATION...
MOST PCPN HAS MOVED SOUTH AND EAST OF THE AREA. A FEW LIGHT RW
MIGHT IMPACT KGLS BUT ALL OTHER TAF SITES SHOULD BE FREE OF PCPN.
MOSTLY VFR CONDITIONS WILL PREVAIL EARLY TONIGHT. ABUNDANT LOW
LEVEL MOISTURE ALONG WITH GROUND WATER WILL LEAD TO DEVELOPMENT OF
LOW CLOUDS AND FOG OVERNIGHT. EXPECT DENSE FOG TO DEVELOP AND
IMPACT ALL TAF SITES MAINLY AFTER 06Z AND IMPROVING AFTER 15Z.
CONDITIONS WILL IMPROVE TO VFR AFTER 18Z. EXPECT ANOTHER ROUND OF
DENSE FOG THURSDAY NIGHT BUT WILL LIKELY BEGIN EARLIER IN THE EVENING.
PREV DISCUSSION... /ISSUED 332 PM CST WED FEB 1 2012/
DISCUSSION...
HOUSTON AIRPORTS CURRENTLY SITTING 2-3 DEGREES BELOW RECORD HIGHS
(82-IAH, 81-HOU) WITH A LIGHT WEST WINDS AND MSUNNY SKIES. PRECIP
HAS MOSTLY CLEARED THE COAST BUT CANNOT RULE OUT A FEW MORE TO POP
UP INLAND CONSIDERING THE WARMTH. STORMS HAVE TEMPORARILY CLEARED
THE SEA FOG OUT OF THE NEARSHORE WATERS BUT DO EXPECT IT TO ROLL
BACK IN OVERNIGHT. ALSO EXPECT SOME FOG TO REDEVELOP INLAND ESP
AFTER MIDNIGHT AHEAD OF A WEAK FRONTAL BOUNDARY THAT WILL EDGE
INTO NRN PARTS OF THE CWA AND STALL.
MOISTURE POOLING SOUTH OF THE BOUNDARY...DAYTIME HEATING AND WEAK
IMPULSES IN THE SW FLOW ALOFT SHOULD PROVIDE ADDITIONAL SCT
SHRA/TSTM ACTIVITY ON THURS. WENT ABOVE GUIDANCE SUGGESTIONS ON
POPS...AND QUITE POSSIBLY NOT HIGH ENOUGH. EXPECT THE STATIONARY
FRONTAL BOUNDARY TO MOVE BACK NORTH AS A WARM FRONT THRU THE DAY
AS LOW PRES DEEPENS TO THE WEST. EXPECT PRECIP TO TAPER OFF FROM
SOUTH TO NORTH THRU THE LATE AFTN HOURS.
REALLY NOT A LOT OF CHANGES FRI - SW FLOW ALOFT...HEATING AND
MOISTURE SHOULD LEAD TO SCT PRECIP. WORTH NOTING THE GOOD DIFFLUENCE
ALOFT DUE TO JET STRUCTURE AND SOMETHING TO KEEP AN EYE ON.
MODELS IN SOMEWHAT BETTER AGREEMENT REGARDING THE TIMING OF THE
NEXT FRONT. LOOKING LIKE IT WILL MOVE INTO SE TX LATE FRI NIGHT
AND OFF THE COAST AROUND NOON SATURDAY. ANTICIPATE A LINE OF
SHRA/TSTMS AHEAD/ALONG THE BOUNDARY.
NOT EXPECTING THINGS TO CLEAR OUT IN THE WAKE OF THE FRONT AS WE
WILL CONTINUE TO REMAIN IN A SW FLOW ALOFT. A SERIES IMPULSES
EMBEDDED IN THIS FLOW ARE FCST TO CONTINUE MOVING OVERHEAD INTO
EARLY NEXT WEEK PROVIDING A CONTINUED CHANCE OF PRECIP. TIMING OF
THESE FEATURES THIS FAR OUT IS NOT MUCH MORE THAN A GUESS...BUT
GFS/ECMWF ARE HINTING AT ANOTHER WET DAY ON SUNDAY. 47
MARINE...
MAIN SHORT TERM FCST ISSUE WILL BE SEA FOG. STORMS HAVE PUSHED IT
OFFSHORE BUT EXPECT IT TO RETURN OVERNIGHT AND PROBABLY CONTINUE
INTO SATURDAY (WITH SHORT TERM VISBY IMPROVEMENTS EACH AFTERNOON).
WINDS/SEAS SHOULD GRADUALLY INCREASE LATE THURS AND FRI AS PRES
GRADIENT TIGHTENS AND ONSHORE FLOW INCREASES. NEXT FRONT FCST TO
PUSH OFF THE COAST EARLY SAT AFTN. EXPECT A LINE OF SHRA/TSTMS
AHEAD OF THE FRONT. 47
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 63 78 63 77 60 / 20 40 20 50 60
HOUSTON (IAH) 64 78 63 77 65 / 10 40 20 50 60
GALVESTON (GLS) 65 72 63 71 63 / 20 30 20 40 40
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...DENSE FOG ADVISORY UNTIL 9 AM CST THURSDAY FOR THE FOLLOWING
ZONES: AUSTIN...BRAZORIA...BRAZOS...BURLESON...CHAMBERS...
COLORADO...FORT BEND...GALVESTON...GRIMES...HARRIS...
HOUSTON...JACKSON...LIBERTY...MADISON...MATAGORDA...
MONTGOMERY...POLK...SAN JACINTO...TRINITY...WALKER...
WALLER...WASHINGTON...WHARTON.
GM...DENSE FOG ADVISORY UNTIL 9 AM CST THURSDAY FOR THE FOLLOWING
ZONES: GALVESTON BAY...MATAGORDA BAY...WATERS FROM FREEPORT
TO THE MATAGORDA SHIP CHANNEL 20 NM TO 60 NM...WATERS FROM
FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20 NM...WATERS
FROM HIGH ISLAND TO FREEPORT 20 TO 60 NM...WATERS FROM HIGH
ISLAND TO FREEPORT OUT 20 NM.
&&
$$
DISCUSSION...45
AVIATION/MARINE...34
AREA FORECAST DISCUSSION...UPDATED
NWS BLACKSBURG VA
406 AM EST THU FEB 2 2012
.SYNOPSIS...
A COLD FRONT WILL SWING ACROSS THE AREA THIS MORNING AND OFFSHORE
THIS AFTERNOON. HIGH PRESSURE BUILDS IN BEHIND THE FRONT LATER
TODAY BRINGING DRIER AND SOMEWHAT COOLER WEATHER FOR THE END OF
THE WORK WEEK. AN AREA OF LOW PRESSURE FROM THE MIDWEST PROVIDES
THE NEXT CHANCE FOR RAIN THIS WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 402 AM EST THURSDAY...
BASED ON REPORTS OF FOG BEING MORE WIDESPREAD...DECIDED TO GO AHEAD
WITH A SHORT TERM DENSE FOG ADVISORY FOR A STRIP RIGHT ALONG THE
BLUE RIDGE GIVEN PERSISTENT VSBYS AOB 1/4 MILE FROM WILKES UP TO
PATRICK CTY. EXPECT WINDS TO QUICKLY MIX THE FOG OUT AFTER SUNRISE
WHEN SHOULD BE ABLE TO CANCEL BUT LIKELY ENOUGH OF A PROBLEM FOR
THE EARLY COMMUTE TO GO WITH THE ADVISORY AT THIS POINT. NO OTHER
CHANGES FOR NOW.
AS OF 255 AM EST THURSDAY...
COLD FRONT AND ASSOCIATED AREAS OF LOW PRESSURE WILL SWING EAST
CROSSING THE MOUNTAINS EARLY THIS MORNING AND THE PIEDMONT BY
MIDDAY. BAND OF CONVECTION JUST AHEAD OF THE WAVE(S) IN
CONJUNCTION WITH A SMALL COMMA HEAD FEATURE UNDER THE UPPER VORT
LOBE MAY USHER IN GROUNDHOG DAY OVER THE NW WITH A RUMBLE OF
THUNDER EARLY THIS MORNING. THIS IN LINE WITH THE LATEST HRRR AND
LOCAL RNK WRF WHICH PUSH THIS FEATURE ACROSS THE GREENBRIER
VALLEY/HIGHLANDS EARLY ON BEFORE WEAKENING HEADING EAST OF THE
RIDGES BY MID MORNING. IN BETWEEN MAY SEE ONLY SCTD SHRA AS THE
TRAILING AXIS TENDS TO SPLIT BUT EXPECT SOME ADDED SHRA BANDS WEST
AS THE FLOW TURNS MORE NW THRU MIDDAY. THUS WILL CARRY LIKELY POPS
ACROSS THE NW/NORTH AND FAR WEST EARLY THIS MORNING...TAPERING TO
CHANCE ELSW AND BASICALLY DRY AFTER EARLY AFTERNOON WITH DRYING
BEHIND THE PASSING FRONT. FOG ANOTHER ISSUE EARLY ON ACROSS THE SW
WHERE SOME CLEARING HAS LEAD TO POCKETS OF VERY DENSE FOG WHICH
CONTINUE TO COVER WITH AN SPS FOR NOW. EXPECT MIXING TO HELP
CLEANSE THINGS OUT TOWARD DAYBREAK AS THE FRONT ARRIVES. OTRW
LOOKING FOR GRADUAL CLEARING FROM NW TO SE THIS AFTERNOON BUT WITH
A GUSTY NW WIND AS THE PRESSURE GRADIENT TIGHTENS BEHIND THE
EXITING LOW AND HIGH PRESSURE TO THE WEST. THINK SHOULD STAY BELOW
ADVISORY LEVELS GIVEN A MARGINAL 85H JET BUT APPEARS MIXING WILL
BE GREAT ENOUGH TO PUSH SOME GUSTS TO 35-40 MPH. FOLLOWED CLOSER
TO THE COOLER MAV MOS WEST TODAY WHERE COOL ADVECTION SHOULD KEEP
READINGS FROM RISING TOO MUCH...WHILE STILL MILD EAST WITH AT
LEAST LOW/MID 60S LIKELY GIVEN DOWNSLOPE.
UPPER TROF LIFTS OUT TONIGHT WITH SHORTWAVE RIDGING SLIDING EAST
ACCOMPANIED BY STRONG SURFACE HIGH PRESSURE BUILDING IN FROM THE NW
LATE. DECENT DRYING SHOULD LEAD TO MAINLY CLEAR SKIES UNDER
DIMINISHING WINDS OVERNIGHT WITH GOOD RAD COOLING BY DAYBREAK. THIS
SHOULD ALLOW TEMPS TO FALL BACK TO BELOW FREEZING VALLEYS WHERE
COULD SOME FOG OTRW LOW/MID 30S FOR THE MOST PART.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
AS OF 330 AM EST THURSDAY...
FRIDAY WILL START OFF WITH OUR AREA UNDER THE INFLUENCE OF A RIDGE
OF HIGH PRESSURE EXTENDING FROM THE WESTERN GREAT LAKES THROUGH THE
EASTERN FACE OF THE APPALACHIANS. WILL EXPECT ABUNDANT SUNSHINE
UNDER MOSTLY CLEAR SKIES...AND FRIDAY AFTERNOON TEMPERATURES WILL
REMAIN ON THE MILD SIDE...DESPITE BEING COOLER THAN THURSDAYS HIGHS.
EXPECT FRIDAY AFTERNOON HIGHS TO BE IN THE MID TO UPPER 50S
AREAWIDE. CLOUD COVER WILL INCREASE FROM THE SOUTHWEST DURING THE
EVENING AS ANOTHER LOW PRESSURE SYSTEM MOVES OUT OF THE CENTRAL
PLAINS...WITH A TROUGH DEVELOPING FROM THE LOW...AND EXTENDING
THROUGH KENTUCKY INTO WESTERN VIRGINIA BY SATURDAY MORNING.
DRIZZLE AND PERIODS OF RAIN WILL DEVELOP ACROSS THE MOUNTAINS
SATURDAY MORNING AND AFTERNOON AS SOUTHEASTERLY WINDS PUSH ATLANTIC
MOISTURE UP THE BLUE RIDGE. RAIN WILL CONTINUE TO SPREAD EAST
THROUGH THE DAY AS THE LOW PRESSURE SYSTEM MOVES OUT OF THE
PLAINS...AND PUSHES ACROSS KENTUCKY AND TENNESEE...WHILE A WARM
FRONT WILL PASS THROUGH OUR AREA FROM THE SOUTHWEST DURING THE
EVENING. DESPITE THE ABUNDANT CLOUD COVER AND PERIODS OF RAIN
KEEPING A LID ON DAYTIME HEATING...TEMPERATURES WILL STILL REMAIN ON
THE MILD SIDE...WITH UPPER 40S AND LOW 50S EXPECTED WEST OF THE BLUE
RIDGE...AND MID 50S TO BE FOUND FURTHER EAST.
ON SUNDAY MORNING...A COLD FRONT WILL PUSH THROUGH OUR REGION...AND
WILL EXIT OUR AREA TO THE SOUTH DURING THE AFTERNOON. SHOWER
ACTIVITY WILL DIMINISH ACROSS THE PIEDMONT REGION DURING THE
AFTERNOON AS THE COLD CONTINUES TO SINK SOUTHWARD...AND HIGH
PRESSURE PUSHES IN FROM THE GREAT LAKES REGION...BUILDING SOUTHWARD
ALONG THE EASTERN FACE OF THE APPALACHIANS. HOWEVER...WILL STILL SEE
SPOTTY SHOWER ACTIVITY ACROSS THE NORTH CAROLINA MOUNTAINS INTO
SUNDAY NIGHT AS THE FRONT REMAINS ANCHORED ALONG THE SOUTHERN
APPALACHIANS.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 330 AM EST THURSDAY...
CONSIDERABLE DIFFERENCES STILL EXIST AMONG THE VARIOUS GUIDANCE
REGARDING THE TIMING AND COVERAGE OR PRECIPITATION ASSOCIATED WITH
THE SYSTEM PASSING THROUGH THE AREA THIS WEEKEND. WILL CONTINUE TO
FAVOR THE GUIDANCE PUT FORTH BY HPC...WHICH LEANS MORE HEAVILY ON
THE ECMWF ENSEMBLE MEAN.
FOR MONDAY...EXPECT ANOTHER ROUND OF SHOWER ACTIVITY...ESPECIALLY
ACROSS EASTERN AND SOUTHERN SECTIONS OF THE REGION...AS A WAVE
DEVELOPS ALONG THE COLD FRONT SITUATED JUST TO THE SOUTH OF OUR
AREA. SHOWER ACTIVITY WILL DIMINISH MONDAY NIGHT AS THE WAVE PUSHES
OFFSHORE AND THE COLD FRONT MOVES FURTHER SOUTH. THE REGION
TRANSITIONS TO A PROLONGED PERIOD OF NORTHWEST FLOW BEHIND FRONT
INTO EARLY NEXT WEEK. MOISTURE WILL BE LIMITED BEHIND THE FRONT. A
REINFORCING SHOT OF COLD AIR ENTERS THE REGION TUESDAY INTO TUESDAY
NIGHT AS A SECOND COLD FRONT MOVES THROUGH THE REGION. ANTICIPATE
ONLY ISOLATED RAIN OR SNOW SHOWERS ACROSS SE WV WITH ITS
PASSAGE...WITH DRY WEATHER ELSEWHERE. THE EASTERN EXTENT OF AN AREA
OF HIGH PRESSURE ARRIVES ON WEDNESDAY ALONG WITH A TREND TOWARD
COLDER TEMPERATURES.
&&
.AVIATION /09Z THURSDAY THROUGH MONDAY/...
AS OF 1159 PM EST WEDNESDAY...
THE FORECAST HAS CHANGED FOR THE EAST. CIGS SHOULD STAY ABOVE 1KFT
FROM ROANOKE EAST...WITH SUB 1KFT CIGS MORE LIKELY IN THE MTNS
UNTIL THE FRONT PASSES TOWARD 12Z. SHOWERS WILL BE MOST
CONCENTRATED FROM LWB TO LYH AND NORTH THE REST OF THE NIGHT AS
DRIER AIR WORKS IN FROM THE SOUTHWEST...WITH THE FRONT MOVING IN
FROM THE NW AROUND 09Z TO 15Z.
LOOK FOR THE CIGS TO IMPROVE TO VFR AT ALL SITES AFTER MIDDAY
THURSDAY. WINDS WILL BE GUSTY FROM THE NW AT 15-25 KNOTS THEN
WEAKENS IN THE EVENING THURSDAY.
WET GROUND MAY SET THE STAGE FOR MVFR VIS WITH INCOMING HIGH
PRESSURE THURSDAY NIGHT.
LOOKS LIKE A RETURN TO VFR ON FRIDAY AS HIGH PRESSURE BUILDS IN
FROM THE NORTH AND BLOCKING PATTERN DEVELOPS. HOWEVER MOISTURE
WILL ATTEMPT TO MAKE A RETURN LATER FRIDAY NIGHT ESPECIALLY ACROSS
WESTERN SITES.
UNSETTLED WEATHER IS THEN EXPECTED FOR THE BULK OF THE
WEEKEND...CIGS DROPPING BACK TO MVFR OR LOWER...WITH LIGHT RAIN
POSSIBLE AS EARLY AS SATURDAY PERHAPS LASTING INTO SUNDAY WITH AN
EASTERLY UPSLOPE FLOW DEVELOPING. ANOTHER FRONT MAY SPREAD RAIN
AND MVFR CIGS INTO LWB/BLF WITH GUSTY WINDS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...DENSE FOG ADVISORY UNTIL 9 AM EST THIS MORNING FOR VAZ032.
NC...DENSE FOG ADVISORY UNTIL 9 AM EST THIS MORNING FOR NCZ003-019.
WV...NONE.
&&
$$
SYNOPSIS...JH/KM
NEAR TERM...JH
SHORT TERM...NF
LONG TERM...DS/NF
AVIATION...JH/KM/WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
339 AM EST THU FEB 2 2012
.SYNOPSIS...
A COLD FRONT WILL SWING ACROSS THE AREA THIS MORNING AND OFFSHORE
THIS AFTERNOON. HIGH PRESSURE BUILDS IN BEHIND THE FRONT LATER
TODAY BRINGING DRIER AND SOMEWHAT COOLER WEATHER FOR THE END OF
THE WORK WEEK. AN AREA OF LOW PRESSURE FROM THE MIDWEST PROVIDES
THE NEXT CHANCE FOR RAIN THIS WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 255 AM EST THURSDAY...
COLD FRONT AND ASSOCIATED AREAS OF LOW PRESSURE WILL SWING EAST
CROSSING THE MOUNTAINS EARLY THIS MORNING AND THE PIEDMONT BY
MIDDAY. BAND OF CONVECTION JUST AHEAD OF THE WAVE(S) IN
CONJUNCTION WITH A SMALL COMMA HEAD FEATURE UNDER THE UPPER VORT
LOBE MAY USHER IN GROUNDHOG DAY OVER THE NW WITH A RUMBLE OF
THUNDER EARLY THIS MORNING. THIS IN LINE WITH THE LATEST HRRR AND
LOCAL RNK WRF WHICH PUSH THIS FEATURE ACROSS THE GREENBRIER
VALLEY/HIGHLANDS EARLY ON BEFORE WEAKENING HEADING EAST OF THE
RIDGES BY MID MORNING. IN BETWEEN MAY SEE ONLY SCTD SHRA AS THE
TRAILING AXIS TENDS TO SPLIT BUT EXPECT SOME ADDED SHRA BANDS WEST
AS THE FLOW TURNS MORE NW THRU MIDDAY. THUS WILL CARRY LIKELY POPS
ACROSS THE NW/NORTH AND FAR WEST EARLY THIS MORNING...TAPERING TO
CHANCE ELSW AND BASICALLY DRY AFTER EARLY AFTERNOON WITH DRYING
BEHIND THE PASSING FRONT. FOG ANOTHER ISSUE EARLY ON ACROSS THE SW
WHERE SOME CLEARING HAS LEAD TO POCKETS OF VERY DENSE FOG WHICH
CONTINUE TO COVER WITH AN SPS FOR NOW. EXPECT MIXING TO HELP
CLEANSE THINGS OUT TOWARD DAYBREAK AS THE FRONT ARRIVES. OTRW
LOOKING FOR GRADUAL CLEARING FROM NW TO SE THIS AFTERNOON BUT WITH
A GUSTY NW WIND AS THE PRESSURE GRADIENT TIGHTENS BEHIND THE
EXITING LOW AND HIGH PRESSURE TO THE WEST. THINK SHOULD STAY BELOW
ADVISORY LEVELS GIVEN A MARGINAL 85H JET BUT APPEARS MIXING WILL
BE GREAT ENOUGH TO PUSH SOME GUSTS TO 35-40 MPH. FOLLOWED CLOSER
TO THE COOLER MAV MOS WEST TODAY WHERE COOL ADVECTION SHOULD KEEP
READINGS FROM RISING TOO MUCH...WHILE STILL MILD EAST WITH AT
LEAST LOW/MID 60S LIKELY GIVEN DOWNSLOPE.
UPPER TROF LIFTS OUT TONIGHT WITH SHORTWAVE RIDGING SLIDING EAST
ACCOMPANIED BY STRONG SURFACE HIGH PRESSURE BUILDING IN FROM THE NW
LATE. DECENT DRYING SHOULD LEAD TO MAINLY CLEAR SKIES UNDER
DIMINISHING WINDS OVERNIGHT WITH GOOD RAD COOLING BY DAYBREAK. THIS
SHOULD ALLOW TEMPS TO FALL BACK TO BELOW FREEZING VALLEYS WHERE
COULD SOME FOG OTRW LOW/MID 30S FOR THE MOST PART.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
AS OF 330 AM EST THURSDAY...
FRIDAY WILL START OFF WITH OUR AREA UNDER THE INFLUENCE OF A RIDGE
OF HIGH PRESSURE EXTENDING FROM THE WESTERN GREAT LAKES THROUGH THE
EASTERN FACE OF THE APPALACHIANS. WILL EXPECT ABUNDANT SUNSHINE
UNDER MOSTLY CLEAR SKIES...AND FRIDAY AFTERNOON TEMPERATURES WILL
REMAIN ON THE MILD SIDE...DESPITE BEING COOLER THAN THURSDAYS HIGHS.
EXPECT FRIDAY AFTERNOON HIGHS TO BE IN THE MID TO UPPER 50S
AREAWIDE. CLOUD COVER WILL INCREASE FROM THE SOUTHWEST DURING THE
EVENING AS ANOTHER LOW PRESSURE SYSTEM MOVES OUT OF THE CENTRAL
PLAINS...WITH A TROUGH DEVELOPING FROM THE LOW...AND EXTENDING
THROUGH KENTUCKY INTO WESTERN VIRGINIA BY SATURDAY MORNING.
DRIZZLE AND PERIODS OF RAIN WILL DEVELOP ACROSS THE MOUNTAINS
SATURDAY MORNING AND AFTERNOON AS SOUTHEASTERLY WINDS PUSH ATLANTIC
MOISTURE UP THE BLUE RIDGE. RAIN WILL CONTINUE TO SPREAD EAST
THROUGH THE DAY AS THE LOW PRESSURE SYSTEM MOVES OUT OF THE
PLAINS...AND PUSHES ACROSS KENTUCKY AND TENNESEE...WHILE A WARM
FRONT WILL PASS THROUGH OUR AREA FROM THE SOUTHWEST DURING THE
EVENING. DESPITE THE ABUNDANT CLOUD COVER AND PERIODS OF RAIN
KEEPING A LID ON DAYTIME HEATING...TEMPERATURES WILL STILL REMAIN ON
THE MILD SIDE...WITH UPPER 40S AND LOW 50S EXPECTED WEST OF THE BLUE
RIDGE...AND MID 50S TO BE FOUND FURTHER EAST.
ON SUNDAY MORNING...A COLD FRONT WILL PUSH THROUGH OUR REGION...AND
WILL EXIT OUR AREA TO THE SOUTH DURING THE AFTERNOON. SHOWER
ACTIVITY WILL DIMINISH ACROSS THE PIEDMONT REGION DURING THE
AFTERNOON AS THE COLD CONTINUES TO SINK SOUTHWARD...AND HIGH
PRESSURE PUSHES IN FROM THE GREAT LAKES REGION...BUILDING SOUTHWARD
ALONG THE EASTERN FACE OF THE APPALACHIANS. HOWEVER...WILL STILL SEE
SPOTTY SHOWER ACTIVITY ACROSS THE NORTH CAROLINA MOUNTAINS INTO
SUNDAY NIGHT AS THE FRONT REMAINS ANCHORED ALONG THE SOUTHERN
APPALACHIANS.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 330 AM EST THURSDAY...
CONSIDERABLE DIFFERENCES STILL EXIST AMONG THE VARIOUS GUIDANCE
REGARDING THE TIMING AND COVERAGE OR PRECIPITATION ASSOCIATED WITH
THE SYSTEM PASSING THROUGH THE AREA THIS WEEKEND. WILL CONTINUE TO
FAVOR THE GUIDANCE PUT FORTH BY HPC...WHICH LEANS MORE HEAVILY ON
THE ECMWF ENSEMBLE MEAN.
FOR MONDAY...EXPECT ANOTHER ROUND OF SHOWER ACTIVITY...ESPECIALLY
ACROSS EASTERN AND SOUTHERN SECTIONS OF THE REGION...AS A WAVE
DEVELOPS ALONG THE COLD FRONT SITUATED JUST TO THE SOUTH OF OUR
AREA. SHOWER ACTIVITY WILL DIMINISH MONDAY NIGHT AS THE WAVE PUSHES
OFFSHORE AND THE COLD FRONT MOVES FURTHER SOUTH. THE REGION
TRANSITIONS TO A PROLONGED PERIOD OF NORTHWEST FLOW BEHIND FRONT
INTO EARLY NEXT WEEK. MOISTURE WILL BE LIMITED BEHIND THE FRONT. A
REINFORCING SHOT OF COLD AIR ENTERS THE REGION TUESDAY INTO TUESDAY
NIGHT AS A SECOND COLD FRONT MOVES THROUGH THE REGION. ANTICIPATE
ONLY ISOLATED RAIN OR SNOW SHOWERS ACROSS SE WV WITH ITS
PASSAGE...WITH DRY WEATHER ELSEWHERE. THE EASTERN EXTENT OF AN AREA
OF HIGH PRESSURE ARRIVES ON WEDNESDAY ALONG WITH A TREND TOWARD
COLDER TEMPERATURES.
&&
.AVIATION /08Z THURSDAY THROUGH MONDAY/...
AS OF 1159 PM EST WEDNESDAY...
THE FORECAST HAS CHANGED FOR THE EAST. CIGS SHOULD STAY ABOVE 1KFT
FROM ROANOKE EAST...WITH SUB 1KFT CIGS MORE LIKELY IN THE MTNS
UNTIL THE FRONT PASSES TOWARD 12Z. SHOWERS WILL BE MOST
CONCENTRATED FROM LWB TO LYH AND NORTH THE REST OF THE NIGHT AS
DRIER AIR WORKS IN FROM THE SOUTHWEST...WITH THE FRONT MOVING IN
FROM THE NW AROUND 09Z TO 15Z.
LOOK FOR THE CIGS TO IMPROVE TO VFR AT ALL SITES AFTER MIDDAY
THURSDAY. WINDS WILL BE GUSTY FROM THE NW AT 15-25 KNOTS THEN
WEAKENS IN THE EVENING THURSDAY.
WET GROUND MAY SET THE STAGE FOR MVFR VIS WITH INCOMING HIGH
PRESSURE THURSDAY NIGHT.
LOOKS LIKE A RETURN TO VFR ON FRIDAY AS HIGH PRESSURE BUILDS IN
FROM THE NORTH AND BLOCKING PATTERN DEVELOPS. HOWEVER MOISTURE
WILL ATTEMPT TO MAKE A RETURN LATER FRIDAY NIGHT ESPECIALLY ACROSS
WESTERN SITES.
UNSETTLED WEATHER IS THEN EXPECTED FOR THE BULK OF THE
WEEKEND...CIGS DROPPING BACK TO MVFR OR LOWER...WITH LIGHT RAIN
POSSIBLE AS EARLY AS SATURDAY PERHAPS LASTING INTO SUNDAY WITH AN
EASTERLY UPSLOPE FLOW DEVELOPING. ANOTHER FRONT MAY SPREAD RAIN
AND MVFR CIGS INTO LWB/BLF WITH GUSTY WINDS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...JH/KM
NEAR TERM...JH
SHORT TERM...NF
LONG TERM...DS/NF
AVIATION...JH/KM/WP
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1034 PM CST WED FEB 1 2012
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND THURSDAY.
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW LOW PRESSURE
OVER SOUTHERN QUEBEC AND A LARGE HIGH PRESSURE SYSTEM STRETCHING
FROM THE SOUTHERN PLAINS INTO THE WESTERN GREAT LAKES. WIDESPREAD
1-2KFT STRATUS EXISTS ACROSS MUCH OF THE WESTERN AND CENTRAL GREAT
LAKES EARLY THIS AFTERNOON...THOUGH EVEN LOWER CEILINGS AND FOG
EXIST BACK TO THE NORTHERN MISSISSIPPI VALLEY. MEANWHILE FARTHER
UPSTREAM...A WEAK SHORTWAVE TROUGH IS DIVING SE OVER THE ND/MANITOBA
BORDER. NOT MUCH PRECIP ACTIVITY WITH THIS WAVE...BUT AS IT TRACKS
TOWARDS NORTHERN WISCONSIN TONIGHT...LIGHT SNOW CHANCES AS WELL AS
CLOUD COVER ARE THE MAIN FORECAST CONCERNS.
TONIGHT...BROAD HIGH PRESSURE OVER THE PLAINS WILL DRIFT
EAST OVER THE WESTERN GREAT LAKES TONIGHT...WHILE A WEAK SHEARED
SHORTWAVE TROUGH DIVES SOUTH OVER NORTHERN WISCONSIN. FORCING IS
PRETTY WEAK WITH THIS WAVE AND MID-LEVELS STRUGGLE TO SATURATE.
STILL THOUGH...DEWPOINT DEPRESSIONS ARE LOW ENOUGH TO WARRANT AT
LEAST FLURRIES OVER NORTHERN WISCONSIN AFTER MIDNIGHT...AND WILL
KEEP A TENTH OR TWO OF ACCUMS ALONG THE U.P. BORDER.
OTHERWISE...THE LIGHT WIND REGIME AND AMPLE MOISTURE STUCK BENEATH
THE BL INVERSION ARE SUPPORTIVE OF THE LOW STRATUS STICKING AROUND
ALL NIGHT LONG. IF HOLES IN THE CLOUDS OCCUR...THEN FOG WOULD
DEVELOP. SO WENT PESSIMISTIC WITH CLOUD COVER FOR THIS FORECAST.
LOWS WILL ONLY FALL A FEW DEGREES WITH THE CLOUD COVER.
THURSDAY...THE SHORTWAVE TROUGH WILL EXIT NE WISCONSIN DURING THE
MORNING AND WILL LEAVE A CHANCE OF FLURRIES IN THE FORECAST.
OTHERWISE...PACIFIC HIGH PRESSURE WILL STICK AROUND THE REGION.
925MB TEMPS DO WARM A FEW DEGREES OVER CENTRAL AND EAST-CENTRAL
WISCONSIN IN THE AFTERNOON. SO WILL SHOW WIDESPREAD LOW STRATUS IN
THE MORNING ERODING THERE FIRST TOMORROW AFTERNOON. TEMPS REMAIN
DIFFICULT PENDING POTENTIAL SUNSHINE AND WILL GO UPPER 30S NORTH TO
MIDDLE 40S SOUTH.
.LONG TERM...THU NGT THRU NXT WED. SPLIT FLOW REMAINS THE RULE
ACROSS THE CONUS DURING THE EXTENDED PART OF THE FCST. ONLY REAL
PBLM TO BE THE EVENTUAL MOVEMENT OF A MODEST CLOSED UPR LOW DURING
THE SUNDAY/MON TIME PERIOD. MDLS HAVE DRIFTED THIS SYSTEM FARTHER
NORTH (ESP THE ECMWF/UKMET) WHICH WOULD NOW BRING A CHC OF PCPN TO
PARTS OF THE FCST AREA. ONCE THIS SYSTEM DEPARTS..A BRIEF SHOT OF
COOLER AIR OVERSPREADS THE GREAT LKS...BUT ONLY APRS TO BE A BLIP
ON THIS WARM WINTER AS TEMPS LOOK TO WARM AGAIN LATER NXT WEEK.
HI PRES TO STRETCH FROM SRN SASKATCHEWAN EWD INTO WRN ONTARIO...
COUPLED WITH ANOTHER HI PRES OVER WRN PA...WL KEEP THE TRANQUIL
WEATHER GOING THU NGT. THERE IS A WEAK THERMAL TROF AT THE SFC
OVER NRN SECTIONS OF THE GREAT LKS WHICH WOULD KEEP MORE CLOUDS
OVER NRN WI THAN CNTRL/E-CNTRL WI. HOWEVER...TIME SECTIONS/FCST
SNDNGS INDICATE THAT MSTR JUST ABV THE SFC MAY BE TRAPPED BLO AN
INVERSION...THUS MOSTLY CLOUDY SKIES EXPECTED THROUGHOUT ALL OF NE
WI. MIN TEMPS WL BE HELD UP BY THESE CLOUDS AND FAVOR THE WARMER
SIDE OF GUIDANCE.
ATTENTION TURNS TOWARD THE CNTRL CONUS AS A CLOSED UPR LOW EXITS
THE ROCKIES AND MOVES INTO THE CNTRL PLAINS ON FRI. INCREASING
SOUTHERLY WINDS ARE EXPECTED TO BEGIN DRAWING GULF MSTR NWD THRU
THE OZARKS INTO THE MID-MS VALLEY WITH SHWRS/TSTMS BREAKING OUT.
MEANWHILE...HI PRES TO EXTEND FROM THE NRN PLAINS EAST THRU NRN
SECTIONS OF THE GREAT LKS AND PROVIDE A DRY EASTERLY FLOW INTO WI.
MAY STILL BE DEALING WITH LINGERING LOW CLOUDS WHICH WOULD PUT A
CRIMP ON MAX TEMPS. FOR NOW...HAVE TEMPERED READINGS DOWN A DEGREE
OR TWO FROM THE PREV FCST...BUT STILL WELL-ABOVE NORMAL.
AS THE UPR LOW SLOWLY TRUDGES ACROSS THE CNTRL PLAINS FRI NGT...
GULF MSTR WL MAKE A SURGE NORTH TOWARD THE GREAT LKS THANKS TO A
50 KT SW LOW-LVL JET. THE AREA OF HI PRES REMAINS ANCHORED OVER
NRN SECTIONS OF THE GREAT LKS...THUS SETTING UP A BATTLE BETWEEN
THE ENTRENCHED DRY AIR AND INCOMING MSTR. HAVE KEPT NRN WI PARTLY
CLOUDY WITH PARTLY TO MOSTLY CLOUDY SKIES FOR CNTRL/E-CNTRL WI.
THIS SET-UP WOULD PROVIDE FOR A WIDE RANGE IN TEMPS WITH THE NORTH
FALLING INTO THE LOWER TO MIDDLE TEENS...WHILE THE LAKESHORE AREAS
ONLY DIP INTO THE MIDDLE TO UPPER 20S. THE CLOSED UPR LOW IS FCST
TO MOVE E-NE INTO THE MIDWEST (VCNTY SRN IA) ON SAT. SOUTHERLY
WINDS OVERRUNNING A WRMFNT STRETCHED FROM THE MIDWEST E-SE INTO
THE OHIO RIVER VALLEY...WL BEGIN TO SPREAD CLOUDS NWD INTO WI BY
SAT AFTERNOON. STILL EXPECT A NICE DAY ACROSS NE WI WITH MAX TEMPS
A GOOD 10 TO 15 DEGS ABV NORMAL.
MDL INCONSISTENTCY PERSISTS WITH THE HANDLING OF THE SYSTEM HEADED
INTO SUNDAY AND THIS RESULTS IN POTENTIALLY SIGNIFICANT SENSIBLE
WEATHER DIFFERENCES FOR THE FCST AREA. IF THIS SYSTEM TRACKS NE...
IT WOULD BRING A LGT SNOW OR SNOW/RAIN THREAT TO MUCH OF NE WI. AN
EWD TRACK WOULD ONLY BRUSH CNTRL/E-CNTRL WI WITH PERHAPS A DUSTING
TO A COUPLE TENTHS OF AN INCH OF SNOW. PREFER TO TAKE A CAUTIOUS
APPROACH HERE UNTIL THE MDLS SETTLE DOWN AND WL ONLY MENTION A SML
POP GENERALLY ALONG/SOUTH OF A MFI-SUE LINE. SML POPS WOULD THEN
BE NEEDED INTO SUNDAY NGT AS THE SYSTEM EITHER MOVES INTO NRN OR
SRN SECTIONS OF THE GREAT LKS RGN. SOME EVIDENCE OF IMPROVING
CONDITIONS FOR MON AS THE SYSTEM PULLS AWAY WITH A WEAK UPR RDG
SLIDING INTO WI. MAX TEMPS TO REMAIN WELL ABV NORMAL WITH PLENTY
OF MIDDLE TO UPPER 30S EXPECTED.
A SECONDARY CDFNT DROPS SWD THRU WI MON NGT...BUT MDLS VARY AS TO
THE EXTENT OF THE COLD AIR TO FILTER INTO THE RGN. THE 12Z ECMWF
HAS BACKED OFF QUITE A BIT WITH 8H TEMPS FALLING INTO THE LOWER TO
MIDDLE TEENS BLO ZERO (COMPARED TO -20C ON ITS PREV RUN). THE GFS
IS COMPARABLE WITH ITS PREV RUN WITH 8H TEMPS AROUND -10C. BASED
ON THE SPLIT FLOW PATN...WL LEAN TOWARD THE GFS SOLN WHICH KEEPS
TEMPS ABV NORMAL THRU TUE. WL NEED TO WATCH FOR POTENTIAL OF LK
EFFECT SNOW SHOWERS FOR VILAS CNTY MON NGT INTO TUE AS TRAJS BECOME
FAVORABLE. HAVE ADDED A SML CHC POP THERE FOR NOW. OTHERWISE...HI
PRES TO START BUILDING EWD FROM THE NRN PLAINS AND KEEP THE REST
OF NE WI ON THE QUIET SIDE. THIS BROAD/STRONG AREA OF HI PRES
SETTLES SOUTH AND EAST ACROSS THE CNTRL CONUS BY NXT WED AND WL
CONT TO PROVIDE DRY CONDITIONS TO NE WI. ANY LK EFFECT ACROSS
VILAS CNTY WL CEASE AS DRIER AIR ADVECTS INTO THE RGN. EVEN THO
TEMPS MAY COOL A BIT...ANTICIPATE READINGS TO REMAIN ABOUT 5 DEGS
ABV NORMAL FOR EARLY FEB.
&&
.AVIATION...
WEST WINDS AHEAD OF SHORT WAVE OVER WESTERN MN TO HELP ADVECT LOW
CLOUDS AND FOG OVER MN/IA INTO WI OVERNIGHT. HIGH PRESSURE AT THE SURFACE
WILL ALSO BUILD INTO THE REGION TONIGHT...LIGHT WINDS AND HIGH
DEW POINTS WOULD PROMOTE FOG FORMATION. THUS WILL STAY WITH
PESSIMISTIC IFR/MVFR CIGS/VSBYS THROUGH MUCH OF THU AFTERNOON. WEAK
UPPER LEVEL DISTURBANCE WILL BRING CHANCE OF FLURRIES TO THE FAR
NORTH OVERNIGHT.
TE
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1031 PM CST WED FEB 1 2012
.SHORT TERM...
1030 PM CST WED FEB 1 2012
EXPANDING DENSE FOG ADVISORY ANOTHER TIER OF COUNTIES EASTWARD.
UPDATED PRODUCTS WILL BE OUT SHORTLY.
.LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY
311 PM CST WED FEB 1 2012
MAIN FORECAST CONCERNS ARE PRECIPITATION CHANCES SATURDAY NIGHT
INTO SUNDAY. THE 01.12Z GFS/ECMWF/GEM CONTINUE TO BE
DIFFERENT IN TIMING AND PLACEMENT OF UPPER LEVEL LOW SLOWLY LIFTING
NORTHEASTWARD INTO THE UPPER GREAT LAKES AND UPPER MIDWEST
SATURDAY NIGHT INTO SUNDAY NIGHT. THE MODELS DO SUGGEST THE
PRECIPITATION IN ASSOCIATION WITH THE UPPER LEVEL LOW WILL BE
CONFINED MAINLY OVER THE SOUTHERN HALF OF THE FORECAST AREA SATURDAY
NIGHT INTO SUNDAY. AS FAR AS PRECIPITATION TYPES...THE 01.12Z GFS
BUFKIT SOUNDINGS DO INDICATE SNOW MAINLY AT NIGHT AND A MIXTURE OF
RAIN AND SNOW DURING THE DAY. AFTER 12Z MONDAY...THE DETERMINISTIC
GEM/GFS/ECMWF ARE IN MUCH BETTER AGREEMENT WITH BUILDING SURFACE
RIDGE INTO THE NORTHERN PLAINS AND THE UPPER MIDWEST. DRY WEATHER
CONDITIONS AND SEASONABLE TEMPERATURES CAN BE EXPECTED ACROSS THE
FORECAST AREA TUESDAY INTO MIDDLE OF NEXT WEEK.
&&
.AVIATION...TONIGHT AND THURSDAY
534 PM CST WED FEB 1 2012
CEILINGS AND VISIBILITIES REMAIN THE MAIN CONCERNS. LIFR
CONDITIONS REMAIN IN PLACE AT KRST LATE THIS AFTERNOON...WHILE
LOWER MVFR CEILINGS RESIDE AT KLSE. WEAK 925MB TROUGH IS LOCATED
OVER SOUTHWEST MINNESOTA...WHERE SURFACE WINDS HAVE SWITCHED TO
THE WEST WHERE VISIBILITIES ARE P6SM. 01.21Z RUC MOVES THIS TROUGH
ACROSS THE TAF SITES BETWEEN 03Z-06Z THIS EVENING...WITH WINDS
BECOMING MORE SOUTHWESTERLY. DRIER AIR LOOKS TO ADVECT INTO THE
AREA AT THIS TIME. THE QUESTION IS WILL THIS BE ENOUGH DRY AIR TO
RAISE THE VISIBILITIES. MODEL TRENDS WOULD SUGGEST YES AND THUS
WENT VISIBILITIES RISING AFTER 03Z AT KRST INTO THE MVFR
CATEGORY. AS FOR KLSE...VISIBILITIES LIKELY TO LOWER PERHAPS INTO
THE 2-3SM RANGE LATER THIS EVENING WITH CEILINGS REMAINING AROUND
010KFT. NOT AS CONFIDENCE WITH CEILINGS RISING UNTIL AFTER 06Z
THOUGH. VFR CONDITIONS THEN LOOK TO SET UP AFTER 15Z AT BOTH TAF
SITES AND CONTINUE THROUGH 00Z FRIDAY.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
1026 PM CST WED FEB 1 2012
WI...DENSE FOG ADVISORY UNTIL 10 AM CST THURSDAY FOR WIZ032-033-041-
053>055-061.
MN...DENSE FOG ADVISORY UNTIL 10 AM CST THURSDAY FOR MNZ079-086>088-
094>096.
IA...DENSE FOG ADVISORY UNTIL 10 AM CST THURSDAY FOR IAZ008>011-018-
019-029-030.
&&
$$
SHORT TERM...RABERDING
LONG TERM....DTJ
AVIATION...RABERDING
AREA FORECAST DISCUSSION
NWS BUFFALO NY
653 AM EST THU FEB 2 2012
.SYNOPSIS...
WEAK HIGH PRESSURE OVER THE REGION WILL TRAP LOW LEVEL MOISTURE AND
KEEP ABUNDANT CLOUD COVER OVER THE AREA THROUGH TONIGHT...WITH
NOTHING MORE THAN A FEW FLURRIES ACROSS THE HIGHER TERRAIN OF
WESTERN NEW YORK. MORE SUNSHINE IS EXPECTED FOR THE WEEKEND.
TEMPERATURES WILL REMAIN JUST ABOVE NORMAL EARLY FEBRUARY READINGS
WITH 30S FOUND ACROSS MUCH OF THE REGION THROUGH THE WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
07Z SURFACE ANALYSIS SHOWED A WEAK HIGH RIDGED FROM JAMES BAY DOWN
ACROSS THE WESTERN GREAT LAKES. THIS HIGH WILL BUILD EASTWARD TODAY
WITH THE RIDGE AXIS EVENTUALLY SETTLING ACROSS THE AREA TONIGHT.
THE PRIMARY FORECAST CONCERN WILL BE WITH THE WIDESPREAD STRATUS
DECK CURRENTLY IN PLACE OVER THE AREA. NORTHERLY COMPONENT IN
PLACE TODAY WILL BE FAVORABLE IN KEEPING CLOUD COVER IN
PLACE...ESPECIALLY ACROSS THE FAVORED UPSLOPE AREAS OF THE WESTERN
SOUTHERN TIER. LATEST RUC MODEL SOUNDINGS AGREE WITH THIS THINKING
AS IT KEEPS LOW LEVEL MOISTURE VALUES QUITE HIGH IN THE LOWEST 3
THOUSAND FEET. WEAK SHORTWAVE PUSHING THROUGH THE UPPER LAKES WILL
PASS ACROSS THE REGION TODAY AND COULD BRING THE POTENTIAL FOR
SOME FLURRIES TO THE WESTERN SOUTHERN TIER AND GENESEE VALLEY. WEAK
COLD AIR ADVECTION AND CLOUD COVER SHOULD KEEP TEMPERATURES PRETTY
MUCH STEADY THROUGH THE DAY AND NOT VARYING MUCH FROM CURRENT
READINGS IN THE LOWER TO MID 30S....BUT UPPER 20S FOR PORTIONS OF
THE NORTH COUNTRY.
RIDGE AXIS ACROSS THE AREA TONIGHT ALONG WITH SOME DRYING BEHIND THE
SHORTWAVE AND BACKING WINDS COULD BRING A BETTER OPPORTUNITY FOR
SOME CLEARING... BUT BASED ON AMOUNT OF UPSTREAM CLOUD CLOUD WILL
NOT BE TOO OPTIMISTIC. OVERNIGHT TEMPERATURES WILL DEPEND GREATLY
ON AMOUNT OF CLEARING IF ANY...WITH MID TO UPPER 20S FOR MOST OF
THE AREA...WITH TEENS ACROSS THE NORTH COUNTRY WITH A BETTER
CHANCE TO SEE ADEQUATE CLEARING.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
THE PERIOD WILL BE RATHER QUIET...AS A BROAD AREA OF HIGH
PRESSURE AT THE SURFACE WILL REMAIN ACROSS THE REGION THROUGH THE
PERIOD. THIS WILL KEEP COLD AIR CUT OFF TO THE NORTH...WITH
TEMPERATURES EXPECTED TO REMAIN ABOVE NORMAL THROUGH THE PERIOD.
THE NEXT SHORTWAVE WILL APPROACH ON FRIDAY WITH A WEAK COLD FRONT
GRAZING THE REGION FRIDAY EVENING AND NIGHT. WILL HAVE CHANCE POPS
FOR FRIDAY MORNING AND AFTERNOON BUT ONLY CARRY PRECIP TYPE AS
FLURRIES AS WILL NOT EXPECT ACCUMULATION...THEN STILL CHANCE POPS
BUT LIGHT SNOW SHOWERS WITH A MINOR ACCUMULATION POSSIBLE. MOISTURE
PROFILE IS MEAGER IN THE MID LEVELS WITH LITTLE IN THE WAY OF
CRYSTAL GROWTH AVAILABLE ALOFT...SOME PRECIP MAY BE AS LIGHT DRIZZLE
DURING THE DAY ON FRIDAY...BUT THERE ARE INDICATIONS ON NAM12 BUFKIT
OF CRYSTAL GROWTH ALOFT DURING LATE AFTERNOON AND EVENING LEADING TO
FLURRIES OR LIGHT SNOW VERSUS DRIZZLE.
TEMPERATURES WILL REMAIN ON THE WARM SIDE FOR THIS TIME OF
YEAR...WITH FRIDAY LIKELY TO RISE INTO THE MID TO UPPER 30S IN MOST
LOCATIONS...LOWER 30S EAST OF LAKE ONTARIO. CLOUDS ASSOCIATED WITH
THE PASSAGE OF THE WEAK COLD FRONT AND SOME LAKE INDUCED CLOUDINESS
WILL KEEP TEMPS UP INITIALLY DURING FRIDAY NIGHT...BUT DRYING AND
CLEARING AFTER MIDNIGHT SHOULD ALLOW TEMPS TO FALL TO THE LOWER 20S
FOR MUCH OF THE FORECAST AREA AND EVEN TO THE LOWER TEENS EAST OF
LAKE ONTARIO.
WEST TO EAST SURFACE RIDGE OF HIGH PRESSURE WILL COVER THE AREA FOR
THE WEEKEND WITH COOLER TEMPS ON SATURDAY IN THE LOWER TO MID 20S
EAST OF LAKE ONTARIO TO LOWER 30S ELSEWHERE...AND THE UPPER 20S TO
MID 30S ON SUNDAY. EXPECT A SLIGHT CHANCE OF FLURRIES SUNDAY AS A
MOISTURE STARVED WAVE DROPS SOUTH THROUGH THE BLOCKED FLOW.
&&
.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
IT WILL BE A FAIRLY QUIET PATTERN THROUGH EARLY NEXT WEEK. THE MAIN
FORECAST CHALLENGE WILL BE TIMING THE EXIT OF A CUT-OFF 500 MB
LOW...WHICH BOTH GFS AND ECMWF MAINTAIN ACROSS THE MIDWESTERN STATES
/NEAR IOWA/ THROUGH AT LEAST 12Z MONDAY. THE 500MB CLOSED LOW WILL
KEEP A BLOCKED FLOW AND EFFECTIVELY PREVENT ANY SIGNIFICANT WEATHER
MAKERS FROM CROSSING OUR AREA. THE LOW IS NOT FORECAST TO OPEN AND
ENTER THE NORTHERN STREAM UNTIL LATER ON MONDAY NIGHT. MONDAY SHOULD
REMAIN FREE OF PRECIP WITH TEMPS CONTINUING TO MODERATE INTO THE
MID/UPR 30S EAST OF LAKE ONTARIO TO THE LOWER 40S ELSEWHERE...THANKS
TO THE RIDGING DOWNSTREAM OF THE MIDWESTERN CLOSED LOW.
THE CLOSED LOW WILL FILL AND MERGE WITH A MUCH HIGHER AMPLITUDE
TROUGH OVER EASTERN CANADA...BRINGING A CHANCE OF SNOW TO THE REGION
ON TUESDAY AND TUESDAY NIGHT AS COLD FRONT CROSSES THE AREA. GFS AND
ECMWF ARE DROPPING A COLD POOL ACROSS QUEBEC AND NORTHERN NY...BUT
THE VERY COLDEST AIR WILL STAY WELL NORTH THEN EAST OF OUR REGION.
BOTH MODELS ALSO PUSH A SURFACE RIDGE ACROSS THE EASTERN GREAT LAKES
AND THE FULL LENGTH OF THE SAINT LAWRENCE RIVER TUESDAY NIGHT...
FOLLOWED QUICKLY BY THE PACIFIC ORIGIN HIGH PRESSURE CENTER ON
WEDNESDAY...THUS ENDING THE CHANCE OF SNOW. AFTER THE MILD START OF
THE WEEK...EXPECT TEMPS TO FALL BACK TO LOWS IN THE UPPER SINGLE
NUMBERS AND TEENS TUESDAY NIGHT WITH HIGHS IN THE MID 20S TO LOWER 30S
DURING WEDNESDAY...NEARLY NORMAL FOR EARLY FEBRUARY.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
WIDESPREAD MVFR CIGS CONTINUING EARLY THIS MORNING. REGIONAL
OBSERVATIONS SUGGESTING CIGS WILL REMAIN BETWEEN 2K AND 25 HUNDRED
FEET THROUGH AT LEAST 15Z. MODEL SOUNDINGS SUGGESTING LOW LEVEL
MOISTURE MAY BE ABLE TO MIX OUT BY AFTERNOON...BUT LIKELY HOLDING
IN ALONG THE WESTERN SOUTHERN TIER IN A NORTHERLY UPSLOPE FLOW.
LOW LEVEL MOISTURE REMAINING IN PLACE TONIGHT AND AREAS WHICH
IMPROVE TO VFR MAY HAVE CIGS RETURN BACK DOWN TO MVFR.
OUTLOOK...
FRIDAY...MAINLY VFR
FRIDAY NIGHT...MVFR CIGS WITH A CHC FOR PRECIPITATION EAST OF
LAKE ONTARIO.
SATURDAY THROUGH MONDAY...MAINLY VFR.
&&
.MARINE...
HIGH PRESSURE OVER THE CENTRAL GREAT LAKES WILL BUILD EASTWARD TODAY
WITH THE RIDGE AXIS ACROSS THE EASTERN GREAT LAKES TONIGHT. THE
PRESSURE GRADIENT HAS ALREADY WEAKENED SUBSTANTIALLY EARLY THIS
MORNING. WINDS AND WAVE WILL CONTINUE TO DECREASE TODAY AS THE RIDGE
AXIS DRAWS CLOSER. THIS HIGH PRESSURE SYSTEM WILL PRODUCE FAVORABLE
MARINE CONDITIONS INTO THE WEEKEND WITH NO FLAGS EXPECTED.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...TMA
NEAR TERM...TMA
SHORT TERM...WCH
LONG TERM...WCH
AVIATION...TMA
MARINE...TMA
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
927 AM EST THU FEB 2 2012
.SYNOPSIS...
A COLD FRONT TO THE NORTH EARLY THIS MORNING WILL DROP SOUTH
THROUGH THE REGION TODAY. HIGH PRESSURE WILL BUILD IN FROM THE
NORTHWEST TONIGHT AND FRIDAY THEN MOVE OFFSHORE SATURDAY. A WARM
FRONT WILL LIFT NORTH INTO THE AREA SATURDAY NIGHT AND STALL
ACROSS THE REGION SUNDAY. THE FRONT WILL PUSH BACK SOUTH SUNDAY
NIGHT. A COLD FRONT WILL APPROACH FROM THE WEST ON MONDAY THEN
CROSS THE REGION MONDAY NIGHT INTO TUESDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 930 AM THURSDAY...PRECIPITATION HAS EXITED THE COAST AND
HAVE DROPPED ALL POPS. SLOW CLEARING WILL ENSUE FOR THE REMAINDER
OF THE MORNING INTO THE AFTERNOON AS DOWNSLOPING FLOW WILL SLOWLY
BUT SURELY ERODE AWAY THE LOW CLOUDINESS THRU MID AFTERNOON.
TEMPERATURES WILL STILL RISE A FEW DEGREES AHEAD OF THE COLD FRONT
WHICH IS NOW LOCATED IN THE WESTERN PIEDMONT AND IS SCHEDULED TO
CROSS OUR REGION LATER IN THE AFTERNOON. MAX TEMPERATURES SHOULD
BE WELL INTO THE 60S OVER MANY AREAS.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/...
AS OF 245 AM THURSDAY...HIGH PRES WILL BUILD IN FROM THE
NW WITH MCLR SKIES EXPECTED. DEWPTS WILL GRAD FALL AND EXPECT LOW
TEMPS TO RANGE FROM CPL DGRS EITHER SIDE OF 40 INLAND TO CPL DGRS
EITHER SIDE OF 45 OBX WHERE WILL HAVE DECENT BRZ.
&&
.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
AS OF 3 AM THU...BELOW AVERAGE CONFIDENCE IN THE LONG TERM
FORECAST AS MODELS NOT IN BEST AGREEMENT WITH TIMING OF A COUPLE
FRONTAL SYSTEMS PROGGED TO IMPACT THE REGION THIS WEEKEND AND INTO
EARLY NEXT WEEK. ECMWF PREFERRED BY HPC AND GENERALLY FOLLOWED A
BLEND OF HPC GUIDANCE AND ECMWF PROGS THROUGH THE PERIOD. FOR FRI
SFC HIGH PRES WILL BE CENTERED OVER THE REGION WITH SHORTWAVE
RIDGING BUILDING IN FROM THE W. MAINLY SUNNY SKIES EXPECTED WITH A
DRY AIRMASS IN PLACE AS INDICATED BY PW`S AROUND 1/4". LOW LEVEL
THICKNESSES AROUND 1320-1330M SUPPORT HIGHS IN THE M/U50S WHICH IS
A LITTLE BELOW MOS GUIDANCE BUT PREFERRED THE COOLER SOLUTION. THE
HIGH SLIDES OFFSHORE SAT WITH SLY RETURN FLOW DEVELOPING BRINGING
SEVERAL DEGREES OF WARMING ACROSS THE REGION. CLOUDS WILL BE
INCREASING ESPECIALLY DURING THE AFTERNOON AS MOISTURE BEGINS INTO
RIDE OVER FLAT RIDGING ACROSS THE REGION. A ROBUST SHORTWAVE
TROUGH PUSHING ACROSS THE NERN CONUS LATE SAT THROUGH SUN WILL
POSITION THE AREA IN FAVORABLE RIGHT ENTRANCE AREA OF THE UPPER JET
AND EXPECT SHOWERS TO DEVELOP SAT NIGHT AIDED BY FORCING FROM A
BACKDOOR COLD FRONT PUSHING S ACROSS THE AREA LATE SAT NIGHT WITH
SHOWERS LINGERING INTO MUCH OF SUN. STILL NOT LOOKING AT A
SIGNIFICANT AMOUNT OF RAIN WITH THIS SYSTEM WITH GENERALLY LESS
THAN A HALF INCH EXPECTED. THE COLD FRONT IS EXPECTED TO BE WELL S
OF THE REGION SUN NIGHT AND EARLY MON WITH HIGH PRES BUILDING IN
FROM THE N AND SHORTWAVE RIDGING BUILDING ALOFT AND EXPECT
MAINLY DRY CONDITIONS. THE NEXT SYSTEM EXPECTED TO QUICKLY MOVE
INTO THE AREA LATER MON INTO TUE AS SRN STREAM ENERGY TAPS INTO
MOISTURE IN THE WRN GOM AND LIFTS IT ACROSS THE SOUTHEAST WITH AN
AREA OF LOW PRES TRACKING ALONG THE COAST. TEMPS LOOK TO BE NEAR
OR A BIT ABOVE NORMAL THROUGH MOST OF THE EXPECTED WITH HIGHS
MAINLY IN THE M/U50S TO L60S AND LOWS IN THE 30S AND 40S. AGAIN
TIMING OF THESE SYSTEMS ARE IN FLUX AS MODELS STILL TRYING TO
GRASP THE AMPLIFIED SPLIT FLOW PATTERN WITH A REX BLOCK ACROSS THE
WRN CONUS LATE THIS WEEK AND INTO THE WEEKEND.
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
SHORT TERM /THROUGH TONIGHT/
AS OF 635 AM THURSDAY...PRECIP ENDING FROM W TO E EARLY THIS
MORN...HOWEVER LOW LVLS FINALLY SATURATED AND CIGS HAVE DROPPED
INTO THE IFR/MVFR RANGE. THINK THIS WILL CONT A FEW MORE HRS WITH
MVFR LIKELY MOST COMMON. FROM MID MORNING ON LOWER LVLS START TO
DRY AND EXPECT CIGS TO LIFT TO VFR THEN SHLD SEE SKIES BECOME MCLR
THIS AFTN. CONT MCLR SKIES AND VFR OVERNIGHT AS GUIDANCE SHOWS
DEWPTS STEADILY LOWERING LIMITING ANY THREAT OF FOG.
LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 3 AM THU...EXPECT VFR CONDITIONS FRI THROUGH SAT WITH HIGH
PRES ACROSS THE REGION...BUT EXPECT INCREASING MOISTURE ACROSS THE
AREA LATE SAT AND SAT NIGHT WITH A COLD FRONT PUSHING S ACROSS
RTES SAT NIGHT. A PERIOD OF MVFR TO IFR CIGS EXPECTED LATE SAT
NIGHT INTO SUN WITH A STRONG LOW LEVEL INVERSION TRAPPING MOISTURE
NEAR THE SFC BEHIND THE FRONT. IMPROVING CONDITIONS EXPECTED LATE IN
THE WEEKEND HOWEVER ANOTHER SYSTEM MOVES INTO THE AREA LATE MON
INTO EARLY TUE WHICH COULD BRING ANOTHER ROUND SUB VFR CONDITIONS.
BELOW NORMAL CONFIDENCE HOWEVER AS MODELS HANDLING THE TIMING OF
THE SYSTEMS DIFFERENTLY.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 935 AM THURSDAY...WINDS CURRENTLY SW AT 10 TO 15 KNOTS WITH
A FEW OCCASIONAL GUSTS TO NEAR 20 KNOTS. SEAS STILL IN THE 2 TO 4
FOOT RANGE. LATEST RUC13 SHOWS WINDS SHOULD REMAIN STEADY OR
INCREASE A BIT AHEAD OF THE FRONT THRU EARLY AFTERNOON. COULD
HAVE A BRIEF SURGE OF NEAR SCA NRLY WINDS BEHIND FRONT BUT FOR NOW
CAPPED AT 20 KTS. LATER TONIGHT GRDNT WILL TIGHTEN ALONG THE CST
AS 1030MB+ HIGH BEGINS TO BUILD IN FROM THE NW. MOST ALL GUIDANCE
SHOWS SOLID 20 KT N WINDS BY 06Z AND SHLD CONT CLOSE TO THAT THRU
MORN OVER CNTRL AND NRN WTRS...THIS WILL LEAD TO SEAS REACHING SCA
LVLS N OF OCRACOKE LATE TONIGHT. ACROSS SRN WTRS WINDS WILL BE A
BIT LIGHTER AND LESS FAVORABLE FETCH WILL KEEP SEAS AOB 5 FT WITH
NO SCA EXPECTED.
LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 3 AM THU...ONGOING SCA CONDITIONS EXPECTED ACROSS PORTIONS
OF THE WATERS FRI WITH NLY FLOW AROUND 15-20 KT AND SEAS AROUND
4-7 FT N OF OCRACOKE INLET AND 2-5 FT S. WINDS WILL DIMINISH
THROUGH THE DAY AS HIGH PRES BUILDS IN FROM THE N ALLOWING FOR
SEAS TO GRADUALLY SUBSIDE AND EXPECT SCA TO END BY AROUND 03Z SAT
FOR ALL WATERS. THE HIGH SLIDES OFFSHORE SAT WITH FLOW BRIEFLY
BECOMING SWLY SAT BUT A BACKDOOR COLD FRONT IS EXPECTED TO PUSH S
ACROSS THE WATERS LATE SAT NIGHT. AT THIS TIME MODELS KEEPING
CONDITIONS BELOW SCA CRITERIA WITH THIS SYSTEM BUT FORECAST
CONFIDENCE IS LOW MAINLY DUE TO TIMING DIFFERENCES AMONG THE
MODELS BUT WOULDN`T BE SURPRISED TO SEE MINIMAL SCA CONDITIONS
ACROSS THE NRN WATERS WITH THE SURGE BEHIND THE FRONT. SCA
CONDITIONS A BETTER BET EARLY NEXT WEEK AS A SRN STREAM SYSTEMS
LIFTS NE ACROSS THE REGION...HOWEVER MODELS MOT IN BEST AGREEMENT
WITH THIS SYSTEM AT THIS TIME EITHER.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 AM TO 10 PM EST FRIDAY FOR AMZ152-
154.
SMALL CRAFT ADVISORY FROM 1 AM TO 7 PM EST FRIDAY FOR AMZ150.
&&
$$
SYNOPSIS...RF
NEAR TERM...CTC
SHORT TERM...RF
LONG TERM...SK
AVIATION...RF/SK
MARINE...CTC/RF/SK
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1015 AM EST THU FEB 2 2012
.SYNOPSIS...
A COLD FRONT WILL SWING ACROSS THE AREA THIS MORNING AND OFFSHORE
THIS AFTERNOON. HIGH PRESSURE BUILDS IN BEHIND THE FRONT LATER
TODAY BRINGING DRIER AND SOMEWHAT COOLER WEATHER FOR THE END OF
THE WORK WEEK. AN AREA OF LOW PRESSURE FROM THE MIDWEST PROVIDES
THE NEXT CHANCE FOR RAIN THIS WEEKEND.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
AS OF 1010 AM EST THURSDAY...
ONLY A FEW SPRINKLES OR A RAIN SHOWER REMAINS ACROSS SE WEST
VA...WHICH SHOULD DECAY IN THE NEXT HOUR OR SO...MAYBE PROVIDING A
SHOWER INTO CRAIG AND NORTHERN ROANOKE COUNTY AS IT MOVES SE. DRIER
AIR WILL EFFICIENTLY MIX OUT CLOUDS WITH SUNSHINE JUST ABOUT CWA
WIDE INTO THE AFTERNOON. WITH THAT...WINDS MAY GUST TO 30 MPH AT
TIMES ACROSS THE RIDGES.
AS OF 402 AM EST THURSDAY...
BASED ON REPORTS OF FOG BEING MORE WIDESPREAD...DECIDED TO GO AHEAD
WITH A SHORT TERM DENSE FOG ADVISORY FOR A STRIP RIGHT ALONG THE
BLUE RIDGE GIVEN PERSISTENT VSBYS AOB 1/4 MILE FROM WILKES UP TO
PATRICK CTY. EXPECT WINDS TO QUICKLY MIX THE FOG OUT AFTER SUNRISE
WHEN SHOULD BE ABLE TO CANCEL BUT LIKELY ENOUGH OF A PROBLEM FOR
THE EARLY COMMUTE TO GO WITH THE ADVISORY AT THIS POINT. NO OTHER
CHANGES FOR NOW.
AS OF 255 AM EST THURSDAY...
COLD FRONT AND ASSOCIATED AREAS OF LOW PRESSURE WILL SWING EAST
CROSSING THE MOUNTAINS EARLY THIS MORNING AND THE PIEDMONT BY
MIDDAY. BAND OF CONVECTION JUST AHEAD OF THE WAVE(S) IN
CONJUNCTION WITH A SMALL COMMA HEAD FEATURE UNDER THE UPPER VORT
LOBE MAY USHER IN GROUNDHOG DAY OVER THE NW WITH A RUMBLE OF
THUNDER EARLY THIS MORNING. THIS IN LINE WITH THE LATEST HRRR AND
LOCAL RNK WRF WHICH PUSH THIS FEATURE ACROSS THE GREENBRIER
VALLEY/HIGHLANDS EARLY ON BEFORE WEAKENING HEADING EAST OF THE
RIDGES BY MID MORNING. IN BETWEEN MAY SEE ONLY SCTD SHRA AS THE
TRAILING AXIS TENDS TO SPLIT BUT EXPECT SOME ADDED SHRA BANDS WEST
AS THE FLOW TURNS MORE NW THRU MIDDAY. THUS WILL CARRY LIKELY POPS
ACROSS THE NW/NORTH AND FAR WEST EARLY THIS MORNING...TAPERING TO
CHANCE ELSW AND BASICALLY DRY AFTER EARLY AFTERNOON WITH DRYING
BEHIND THE PASSING FRONT. FOG ANOTHER ISSUE EARLY ON ACROSS THE SW
WHERE SOME CLEARING HAS LEAD TO POCKETS OF VERY DENSE FOG WHICH
CONTINUE TO COVER WITH AN SPS FOR NOW. EXPECT MIXING TO HELP
CLEANSE THINGS OUT TOWARD DAYBREAK AS THE FRONT ARRIVES. OTRW
LOOKING FOR GRADUAL CLEARING FROM NW TO SE THIS AFTERNOON BUT WITH
A GUSTY NW WIND AS THE PRESSURE GRADIENT TIGHTENS BEHIND THE
EXITING LOW AND HIGH PRESSURE TO THE WEST. THINK SHOULD STAY BELOW
ADVISORY LEVELS GIVEN A MARGINAL 85H JET BUT APPEARS MIXING WILL
BE GREAT ENOUGH TO PUSH SOME GUSTS TO 35-40 MPH. FOLLOWED CLOSER
TO THE COOLER MAV MOS WEST TODAY WHERE COOL ADVECTION SHOULD KEEP
READINGS FROM RISING TOO MUCH...WHILE STILL MILD EAST WITH AT
LEAST LOW/MID 60S LIKELY GIVEN DOWNSLOPE.
UPPER TROF LIFTS OUT TONIGHT WITH SHORTWAVE RIDGING SLIDING EAST
ACCOMPANIED BY STRONG SURFACE HIGH PRESSURE BUILDING IN FROM THE NW
LATE. DECENT DRYING SHOULD LEAD TO MAINLY CLEAR SKIES UNDER
DIMINISHING WINDS OVERNIGHT WITH GOOD RAD COOLING BY DAYBREAK. THIS
SHOULD ALLOW TEMPS TO FALL BACK TO BELOW FREEZING VALLEYS WHERE
COULD SOME FOG OTRW LOW/MID 30S FOR THE MOST PART.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH SUNDAY NIGHT/...
AS OF 330 AM EST THURSDAY...
FRIDAY WILL START OFF WITH OUR AREA UNDER THE INFLUENCE OF A RIDGE
OF HIGH PRESSURE EXTENDING FROM THE WESTERN GREAT LAKES THROUGH THE
EASTERN FACE OF THE APPALACHIANS. WILL EXPECT ABUNDANT SUNSHINE
UNDER MOSTLY CLEAR SKIES...AND FRIDAY AFTERNOON TEMPERATURES WILL
REMAIN ON THE MILD SIDE...DESPITE BEING COOLER THAN THURSDAYS HIGHS.
EXPECT FRIDAY AFTERNOON HIGHS TO BE IN THE MID TO UPPER 50S
AREAWIDE. CLOUD COVER WILL INCREASE FROM THE SOUTHWEST DURING THE
EVENING AS ANOTHER LOW PRESSURE SYSTEM MOVES OUT OF THE CENTRAL
PLAINS...WITH A TROUGH DEVELOPING FROM THE LOW...AND EXTENDING
THROUGH KENTUCKY INTO WESTERN VIRGINIA BY SATURDAY MORNING.
DRIZZLE AND PERIODS OF RAIN WILL DEVELOP ACROSS THE MOUNTAINS
SATURDAY MORNING AND AFTERNOON AS SOUTHEASTERLY WINDS PUSH ATLANTIC
MOISTURE UP THE BLUE RIDGE. RAIN WILL CONTINUE TO SPREAD EAST
THROUGH THE DAY AS THE LOW PRESSURE SYSTEM MOVES OUT OF THE
PLAINS...AND PUSHES ACROSS KENTUCKY AND TENNESSEE...WHILE A WARM
FRONT WILL PASS THROUGH OUR AREA FROM THE SOUTHWEST DURING THE
EVENING. DESPITE THE ABUNDANT CLOUD COVER AND PERIODS OF RAIN
KEEPING A LID ON DAYTIME HEATING...TEMPERATURES WILL STILL REMAIN ON
THE MILD SIDE...WITH UPPER 40S AND LOW 50S EXPECTED WEST OF THE BLUE
RIDGE...AND MID 50S TO BE FOUND FURTHER EAST.
ON SUNDAY MORNING...A COLD FRONT WILL PUSH THROUGH OUR REGION...AND
WILL EXIT OUR AREA TO THE SOUTH DURING THE AFTERNOON. SHOWER
ACTIVITY WILL DIMINISH ACROSS THE PIEDMONT REGION DURING THE
AFTERNOON AS THE COLD CONTINUES TO SINK SOUTHWARD...AND HIGH
PRESSURE PUSHES IN FROM THE GREAT LAKES REGION...BUILDING SOUTHWARD
ALONG THE EASTERN FACE OF THE APPALACHIANS. HOWEVER...WILL STILL SEE
SPOTTY SHOWER ACTIVITY ACROSS THE NORTH CAROLINA MOUNTAINS INTO
SUNDAY NIGHT AS THE FRONT REMAINS ANCHORED ALONG THE SOUTHERN
APPALACHIANS.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 330 AM EST THURSDAY...
CONSIDERABLE DIFFERENCES STILL EXIST AMONG THE VARIOUS GUIDANCE
REGARDING THE TIMING AND COVERAGE OR PRECIPITATION ASSOCIATED WITH
THE SYSTEM PASSING THROUGH THE AREA THIS WEEKEND. WILL CONTINUE TO
FAVOR THE GUIDANCE PUT FORTH BY HPC...WHICH LEANS MORE HEAVILY ON
THE ECMWF ENSEMBLE MEAN.
FOR MONDAY...EXPECT ANOTHER ROUND OF SHOWER ACTIVITY...ESPECIALLY
ACROSS EASTERN AND SOUTHERN SECTIONS OF THE REGION...AS A WAVE
DEVELOPS ALONG THE COLD FRONT SITUATED JUST TO THE SOUTH OF OUR
AREA. SHOWER ACTIVITY WILL DIMINISH MONDAY NIGHT AS THE WAVE PUSHES
OFFSHORE AND THE COLD FRONT MOVES FURTHER SOUTH. THE REGION
TRANSITIONS TO A PROLONGED PERIOD OF NORTHWEST FLOW BEHIND FRONT
INTO EARLY NEXT WEEK. MOISTURE WILL BE LIMITED BEHIND THE FRONT. A
REINFORCING SHOT OF COLD AIR ENTERS THE REGION TUESDAY INTO TUESDAY
NIGHT AS A SECOND COLD FRONT MOVES THROUGH THE REGION. ANTICIPATE
ONLY ISOLATED RAIN OR SNOW SHOWERS ACROSS SE WV WITH ITS
PASSAGE...WITH DRY WEATHER ELSEWHERE. THE EASTERN EXTENT OF AN AREA
OF HIGH PRESSURE ARRIVES ON WEDNESDAY ALONG WITH A TREND TOWARD
COLDER TEMPERATURES.
&&
.AVIATION /15Z THURSDAY THROUGH MONDAY/...
AS OF 615 AM EST THURSDAY...
COLD FRONT CURRENTLY CROSSING THE MOUNTAINS WITH WIDESPREAD
MVFR/IFR CIGS ON THE WESTERN SLOPES AND AREAS OF IFR IN LOW
CLOUDS/FOG IN THE EAST. AS THE FRONT PASSES WILL SEE BANDS OF SHRA
AFFECT MUCH OF THE REGION WITH OCNL MVFR VSBYS THRU MID MORNING
BEFORE THE SHOWERS END. HOWEVER STILL EXPECT LOW CIGS TO HANG ON
IN SPOTS THIS MORNING BEFORE IMPROVING TO VFR AT ALL SITES AFTER
MIDDAY AS DEEPER MOISTURE EXITS. BEHIND THE FRONT...WINDS WILL BE GUSTY
FROM THE NW AT 15-30 KNOTS THEN DIMINISHING THIS EVENING AND
BECOMING NEAR CALM OVERNIGHT. THIS IN COMBO WITH THE WET GROUND
MAY ALLOW FOR AREAS OF MVFR IN FOG CLOSER TO THE RIVER BOTTOMS
AROUND KLWB AND PERHAPS KBCB LATE.
OTRW LOOKS LIKE A RETURN TO VFR ON FRIDAY AS HIGH PRESSURE BUILDS
IN FROM THE NORTH AND A BLOCKING PATTERN DEVELOPS. HOWEVER
MOISTURE WILL ATTEMPT TO MAKE A RETURN LATER FRIDAY NIGHT
ESPECIALLY ACROSS WESTERN SITES.
EXTENDED OUTLOOK PERIOD REMAINS LOW CONFIDENCE AT THIS POINT
PENDING HOW FAR NORTH/EAST MOISTURE WITH THE NEXT SYSTEM MAKES IT
AND EXACTLY WHEN. COULD SEE SOME LOWER CIGS AND LIGHT RAIN ARRIVE
AS EARLY AS SATURDAY...BUT APPEARS MOST LIKELY SAT NIGHT INTO
SUNDAY AS LOW PRESSURE STALLS TO THE WEST AND THEN SHEARS MOISTURE
UNDERNEATH HIGH PRESSURE TO THE NORTH AS EASTERLY UPSLOPE FLOW
DEVELOPS. THIS SCENARIO WITH AT LEAST MVFR CIGS AND RAIN COULD
LAST INTO EARLY NEXT WEEK AS ANOTHER WAVE MOVES UP FROM THE GULF
STATES BUT VERY IFFY AT THIS POINT.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...JH/KM
NEAR TERM...JH/KM
SHORT TERM...NF
LONG TERM...DS/NF
AVIATION...JH/KM/WP
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
630 AM EST THU FEB 2 2012
.SYNOPSIS...
A COLD FRONT WILL SWING ACROSS THE AREA THIS MORNING AND OFFSHORE
THIS AFTERNOON. HIGH PRESSURE BUILDS IN BEHIND THE FRONT LATER
TODAY BRINGING DRIER AND SOMEWHAT COOLER WEATHER FOR THE END OF
THE WORK WEEK. AN AREA OF LOW PRESSURE FROM THE MIDWEST PROVIDES
THE NEXT CHANCE FOR RAIN THIS WEEKEND.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 402 AM EST THURSDAY...
BASED ON REPORTS OF FOG BEING MORE WIDESPREAD...DECIDED TO GO AHEAD
WITH A SHORT TERM DENSE FOG ADVISORY FOR A STRIP RIGHT ALONG THE
BLUE RIDGE GIVEN PERSISTENT VSBYS AOB 1/4 MILE FROM WILKES UP TO
PATRICK CTY. EXPECT WINDS TO QUICKLY MIX THE FOG OUT AFTER SUNRISE
WHEN SHOULD BE ABLE TO CANCEL BUT LIKELY ENOUGH OF A PROBLEM FOR
THE EARLY COMMUTE TO GO WITH THE ADVISORY AT THIS POINT. NO OTHER
CHANGES FOR NOW.
AS OF 255 AM EST THURSDAY...
COLD FRONT AND ASSOCIATED AREAS OF LOW PRESSURE WILL SWING EAST
CROSSING THE MOUNTAINS EARLY THIS MORNING AND THE PIEDMONT BY
MIDDAY. BAND OF CONVECTION JUST AHEAD OF THE WAVE(S) IN
CONJUNCTION WITH A SMALL COMMA HEAD FEATURE UNDER THE UPPER VORT
LOBE MAY USHER IN GROUNDHOG DAY OVER THE NW WITH A RUMBLE OF
THUNDER EARLY THIS MORNING. THIS IN LINE WITH THE LATEST HRRR AND
LOCAL RNK WRF WHICH PUSH THIS FEATURE ACROSS THE GREENBRIER
VALLEY/HIGHLANDS EARLY ON BEFORE WEAKENING HEADING EAST OF THE
RIDGES BY MID MORNING. IN BETWEEN MAY SEE ONLY SCTD SHRA AS THE
TRAILING AXIS TENDS TO SPLIT BUT EXPECT SOME ADDED SHRA BANDS WEST
AS THE FLOW TURNS MORE NW THRU MIDDAY. THUS WILL CARRY LIKELY POPS
ACROSS THE NW/NORTH AND FAR WEST EARLY THIS MORNING...TAPERING TO
CHANCE ELSW AND BASICALLY DRY AFTER EARLY AFTERNOON WITH DRYING
BEHIND THE PASSING FRONT. FOG ANOTHER ISSUE EARLY ON ACROSS THE SW
WHERE SOME CLEARING HAS LEAD TO POCKETS OF VERY DENSE FOG WHICH
CONTINUE TO COVER WITH AN SPS FOR NOW. EXPECT MIXING TO HELP
CLEANSE THINGS OUT TOWARD DAYBREAK AS THE FRONT ARRIVES. OTRW
LOOKING FOR GRADUAL CLEARING FROM NW TO SE THIS AFTERNOON BUT WITH
A GUSTY NW WIND AS THE PRESSURE GRADIENT TIGHTENS BEHIND THE
EXITING LOW AND HIGH PRESSURE TO THE WEST. THINK SHOULD STAY BELOW
ADVISORY LEVELS GIVEN A MARGINAL 85H JET BUT APPEARS MIXING WILL
BE GREAT ENOUGH TO PUSH SOME GUSTS TO 35-40 MPH. FOLLOWED CLOSER
TO THE COOLER MAV MOS WEST TODAY WHERE COOL ADVECTION SHOULD KEEP
READINGS FROM RISING TOO MUCH...WHILE STILL MILD EAST WITH AT
LEAST LOW/MID 60S LIKELY GIVEN DOWNSLOPE.
UPPER TROF LIFTS OUT TONIGHT WITH SHORTWAVE RIDGING SLIDING EAST
ACCOMPANIED BY STRONG SURFACE HIGH PRESSURE BUILDING IN FROM THE NW
LATE. DECENT DRYING SHOULD LEAD TO MAINLY CLEAR SKIES UNDER
DIMINISHING WINDS OVERNIGHT WITH GOOD RAD COOLING BY DAYBREAK. THIS
SHOULD ALLOW TEMPS TO FALL BACK TO BELOW FREEZING VALLEYS WHERE
COULD SOME FOG OTRW LOW/MID 30S FOR THE MOST PART.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
AS OF 330 AM EST THURSDAY...
FRIDAY WILL START OFF WITH OUR AREA UNDER THE INFLUENCE OF A RIDGE
OF HIGH PRESSURE EXTENDING FROM THE WESTERN GREAT LAKES THROUGH THE
EASTERN FACE OF THE APPALACHIANS. WILL EXPECT ABUNDANT SUNSHINE
UNDER MOSTLY CLEAR SKIES...AND FRIDAY AFTERNOON TEMPERATURES WILL
REMAIN ON THE MILD SIDE...DESPITE BEING COOLER THAN THURSDAYS HIGHS.
EXPECT FRIDAY AFTERNOON HIGHS TO BE IN THE MID TO UPPER 50S
AREAWIDE. CLOUD COVER WILL INCREASE FROM THE SOUTHWEST DURING THE
EVENING AS ANOTHER LOW PRESSURE SYSTEM MOVES OUT OF THE CENTRAL
PLAINS...WITH A TROUGH DEVELOPING FROM THE LOW...AND EXTENDING
THROUGH KENTUCKY INTO WESTERN VIRGINIA BY SATURDAY MORNING.
DRIZZLE AND PERIODS OF RAIN WILL DEVELOP ACROSS THE MOUNTAINS
SATURDAY MORNING AND AFTERNOON AS SOUTHEASTERLY WINDS PUSH ATLANTIC
MOISTURE UP THE BLUE RIDGE. RAIN WILL CONTINUE TO SPREAD EAST
THROUGH THE DAY AS THE LOW PRESSURE SYSTEM MOVES OUT OF THE
PLAINS...AND PUSHES ACROSS KENTUCKY AND TENNESEE...WHILE A WARM
FRONT WILL PASS THROUGH OUR AREA FROM THE SOUTHWEST DURING THE
EVENING. DESPITE THE ABUNDANT CLOUD COVER AND PERIODS OF RAIN
KEEPING A LID ON DAYTIME HEATING...TEMPERATURES WILL STILL REMAIN ON
THE MILD SIDE...WITH UPPER 40S AND LOW 50S EXPECTED WEST OF THE BLUE
RIDGE...AND MID 50S TO BE FOUND FURTHER EAST.
ON SUNDAY MORNING...A COLD FRONT WILL PUSH THROUGH OUR REGION...AND
WILL EXIT OUR AREA TO THE SOUTH DURING THE AFTERNOON. SHOWER
ACTIVITY WILL DIMINISH ACROSS THE PIEDMONT REGION DURING THE
AFTERNOON AS THE COLD CONTINUES TO SINK SOUTHWARD...AND HIGH
PRESSURE PUSHES IN FROM THE GREAT LAKES REGION...BUILDING SOUTHWARD
ALONG THE EASTERN FACE OF THE APPALACHIANS. HOWEVER...WILL STILL SEE
SPOTTY SHOWER ACTIVITY ACROSS THE NORTH CAROLINA MOUNTAINS INTO
SUNDAY NIGHT AS THE FRONT REMAINS ANCHORED ALONG THE SOUTHERN
APPALACHIANS.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
AS OF 330 AM EST THURSDAY...
CONSIDERABLE DIFFERENCES STILL EXIST AMONG THE VARIOUS GUIDANCE
REGARDING THE TIMING AND COVERAGE OR PRECIPITATION ASSOCIATED WITH
THE SYSTEM PASSING THROUGH THE AREA THIS WEEKEND. WILL CONTINUE TO
FAVOR THE GUIDANCE PUT FORTH BY HPC...WHICH LEANS MORE HEAVILY ON
THE ECMWF ENSEMBLE MEAN.
FOR MONDAY...EXPECT ANOTHER ROUND OF SHOWER ACTIVITY...ESPECIALLY
ACROSS EASTERN AND SOUTHERN SECTIONS OF THE REGION...AS A WAVE
DEVELOPS ALONG THE COLD FRONT SITUATED JUST TO THE SOUTH OF OUR
AREA. SHOWER ACTIVITY WILL DIMINISH MONDAY NIGHT AS THE WAVE PUSHES
OFFSHORE AND THE COLD FRONT MOVES FURTHER SOUTH. THE REGION
TRANSITIONS TO A PROLONGED PERIOD OF NORTHWEST FLOW BEHIND FRONT
INTO EARLY NEXT WEEK. MOISTURE WILL BE LIMITED BEHIND THE FRONT. A
REINFORCING SHOT OF COLD AIR ENTERS THE REGION TUESDAY INTO TUESDAY
NIGHT AS A SECOND COLD FRONT MOVES THROUGH THE REGION. ANTICIPATE
ONLY ISOLATED RAIN OR SNOW SHOWERS ACROSS SE WV WITH ITS
PASSAGE...WITH DRY WEATHER ELSEWHERE. THE EASTERN EXTENT OF AN AREA
OF HIGH PRESSURE ARRIVES ON WEDNESDAY ALONG WITH A TREND TOWARD
COLDER TEMPERATURES.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
AS OF 615 AM EST THURSDAY...
COLD FRONT CURRENTLY CROSSING THE MOUNTAINS WITH WIDESPREAD
MVFR/IFR CIGS ON THE WESTERN SLOPES AND AREAS OF IFR IN LOW
CLOUDS/FOG IN THE EAST. AS THE FRONT PASSES WILL SEE BANDS OF SHRA
AFFECT MUCH OF THE REGION WITH OCNL MVFR VSBYS THRU MID MORNING
BEFORE THE SHOWERS END. HOWEVER STILL EXPECT LOW CIGS TO HANG ON
IN SPOTS THIS MORNING BEFORE IMPROVING TO VFR AT ALL SITES AFTER
MIDDAY AS DEEPER MOISTURE EXITS. BEHIND THE FRONT...WINDS WILL BE GUSTY
FROM THE NW AT 15-30 KNOTS THEN DIMINISHING THIS EVENING AND
BECOMING NEAR CALM OVERNIGHT. THIS IN COMBO WITH THE WET GROUND
MAY ALLOW FOR AREAS OF MVFR IN FOG CLOSER TO THE RIVER BOTTOMS
AROUND KLWB AND PERHAPS KBCB LATE.
OTRW LOOKS LIKE A RETURN TO VFR ON FRIDAY AS HIGH PRESSURE BUILDS
IN FROM THE NORTH AND A BLOCKING PATTERN DEVELOPS. HOWEVER
MOISTURE WILL ATTEMPT TO MAKE A RETURN LATER FRIDAY NIGHT
ESPECIALLY ACROSS WESTERN SITES.
EXTENDED OUTLOOK PERIOD REMAINS LOW CONFIDENCE AT THIS POINT
PENDING HOW FAR NORTH/EAST MOISTURE WITH THE NEXT SYSTEM MAKES IT
AND EXACTLY WHEN. COULD SEE SOME LOWER CIGS AND LIGHT RAIN ARRIVE
AS EARLY AS SATURDAY...BUT APPEARS MOST LIKELY SAT NIGHT INTO
SUNDAY AS LOW PRESSURE STALLS TO THE WEST AND THEN SHEARS MOISTURE
UNDERNEATH HIGH PRESSURE TO THE NORTH AS EASTERLY UPSLOPE FLOW
DEVELOPS. THIS SCENARIO WITH AT LEAST MVFR CIGS AND RAIN COULD
LAST INTO EARLY NEXT WEEK AS ANOTHER WAVE MOVES UP FROM THE GULF
STATES BUT VERY IFFY AT THIS POINT.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...DENSE FOG ADVISORY UNTIL 9 AM EST THIS MORNING FOR VAZ032.
NC...DENSE FOG ADVISORY UNTIL 9 AM EST THIS MORNING FOR NCZ003-019.
WV...NONE.
&&
$$
SYNOPSIS...JH/KM
NEAR TERM...JH
SHORT TERM...NF
LONG TERM...DS/NF
AVIATION...JH/KM/WP
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
559 PM EST THU FEB 2 2012
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW
&&
.SYNOPSIS...
HIGH PRESSURE OVER NORTHERN INDIANA AND THE SOUTHERN GREAT LAKES
WILL CONTINUE MOVING EAST. MEANWHILE AN UPPER TROUGH OVER THE
CENTRAL ROCKIES WILL DEVELOP INTO A CLOSED UPPER LOW AND MOVE OUR
WAY SATURDAY AND SATURDAY NIGHT. A SURFACE LOW PRESSURE SYSTEM WILL
TRACK ACROSS KENTUCKY AND TENNESSEE SATURDAY AND SATURDAY NIGHT.
HIGH PRESSURE BEHIND THIS SYSTEM WILL BUILD OUR WAY LATE SUNDAY AND
MONDAY. IN THE EXTENDED HIGH PRESSURE WILL DOMINATE OUR WEATHER.
HOWEVER A WEAK AND DRY COLD FRONT WILL MOVE ACROSS OUR REGION AROUND
THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /TONIGHT/...
AREAS OF FOG AND STRATUS EARLIER OVER THE WESTERN PART OF OUR REGION
HAS TAKEN MOST OF THE DAY TO CLEAR OUT. HIGH PRESSURE WILL BRING
LIGHT WINDS AND MOSTLY CLEAR SKIES EARLY ON AND THERE IS SOME
POTENTIAL FOG SOME FOG AGAIN TONIGHT. ON THE OTHER HAND...THERE
WILL BE MORE CIRRUS MOVING IN OVERNIGHT WHICH WOULD LESSEN THE
POTENTIAL FOR FOG. THE 15Z VSREF SHOWS PRACTICALLY NO POTENTIAL FOR
FOG...WHILE THE RUC SOUNDINGS INDICATE A MUCH GREATER POTENTIAL FOG
FOG. THE WINDS AND CLOUDS LATER TONIGHT WILL LESSEN THE POTENTIAL
QUITE A BIT. BUT WITH SOME UNCERTAINTY WILL MENTION PATCHY FOG MOST
AREAS LATE TONIGHT. I DON`T THINK THERE WILL BE WIDESPREAD DENSE
FOG AS THERE WAS LAST NIGHT.
WITH CLEAR SKIES AND LIGHT WINDS WILL UNDERCUT MOS TEMPERATURES A
LITTLE TONIGHT. MOST AREAS LAST NIGHT ENDED SEVERAL DEGREES COOLER.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
THE HIGHEST DEWPOINTS AND LIGHTEST WINDS WILL BE ACROSS OUR NORTH
AND NORTHEAST SECTIONS FRIDAY MORNING. WILL MENTION SOME PATCHY FOG
ALL BUT FAR SOUTHWEST EARLY FRIDAY. OTHERWISE...FRIDAY WILL BE
ANOTHER VERY NICE DAY WITH INCREASING HIGH CLOUDS. WENT CLOSE TO A
MET/MAV BLEND ON TEMPERATURES.
ALL MODELS SPREAD RAIN INTO OUR REGION FRIDAY NIGHT AND SATURDAY
APPEARS TO BE A VERY WET DAY WITH PERIODS OF RAIN MOST AREAS. BUT
WITH SLIGHTLY LESSER CHANCES ACROSS OUR FAR NORTH. AS FAR AS
TEMPERATURES WENT SLIGHTLY ABOVE MAV/MET BLEND FRIDAY NIGHT AND
SLIGHTLY BELOW SATURDAY AS CLOUDS AND PRECIP SHOULD LIMIT ANY
DIURNAL TREND ON TEMPERATURES.
1000 TO 850 MB THICKNESS DROP TO NEAR OR SLIGHTLY BELOW 1300 METERS
LATE SATURDAY NIGHT ACROSS OUR NORTH AND WILL MENTION CHANCE OF
MIXED PRECIP THERE. BUT IT IS POSSIBLE THE PRECIP MAY BE OVER
ACROSS OUR NORTH BY THAT TIME.
MODELS START TO MOVE THE UPPER LOW TO THE SOUTHEAST AS AN UPPER
RIDGE DEVELOPS OVER THE NORTHERN PLAINS. JUST ABOUT ALL MODELS NOW
LEAN TOWARDS A DRY DAY SUNDAY. BUT WITH AN UPPER TROUGH STILL OVER
OUR REGION 12Z-18Z SUNDAY...I AM STILL A BIT RELUCTANT TO JUMP ON
THE DRY BAND WAGON YET SUNDAY WITH THE POSSIBLE EXCEPTION OF OUR
NORTHERN AREAS WOULD DRY OUT FIRST. EITHER CASE...ANY REMAINING
PRECIP WILL END DURING THE DAY SUNDAY AS THE UPPER TROUGH MOVES TO
THE SOUTHEAST. DID NOT MAKE ANY SIGNIFICANT CHANGES TO TEMPERATURES
SUNDAY.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
QUIET PATTERN FOR THE LONG TERM. MODELS ARE MOVING THE TROUGH AXIS
THROUGH A LITTLE BIT FASTER SUNDAY SO BY SUNDAY NIGHT IT LOOKS LIKE
ALL PRECIP SHOULD HAVE MOVED OUT OF THE AREA. WITH THE VESTIGES OF
AN UPPER LOW STILL HANGING AROUND UPSTREAM AND MOVING ACROSS ON
MONDAY COULD SEE A LITTLE INCREASED CLOUD COVER BUT THAT/S IT GIVEN
THE LACK OF MOISTURE AND LACK OF FORCING. AFTER THAT MOVES THROUGH
MONDAY UPPER FLOW INCLUDES A DEEP UPPER LOW MOVING INTO ST JAMES BAY
AND ANOTHER UPPER LOW DIGGING INTO WESTERN MEXICO BUT VERY LITTLE
GOING ON ELSEWHERE. TEMPERATURES LOOK A LITTLE WARMER THAN AVERAGE
FOR THIS TIME OF YEAR BUT ALLBLEND CAPTURED THIS WELL. ONLY CHANGES
TO ALLBLEND FOR POPS WAS TO REMOVE SLIGHT CHANCE IN THE SOUTH ON
SUNDAY NIGHT DUE TO FASTER MOVEMENT OF THE TROUGH AND REMOVAL OF
SLIGHT CHANCE POPS IN DAY 7 WITH ENSEMBLES AND OPERATIONAL GFS
FAVORING DRY.
&&
.AVIATION /DISCUSSION FOR 030000Z TAFS/...
BY FAR THE MOST IMPORTANT QUESTION IS FOG AND VISIBILITIES. WE
HAVE HAD A DAY TO DRY SOIL SOMEWHAT...BUT DEWPOINT SPREADS AND
WINDS NOT VERY DIFFERENT FROM SAME TIME LAST NIGHT...WHEN FOG
BECAME WIDESPREAD AND DENSE.
THIS MEANS FOG WILL PROBABLY NOT BE QUITE AS LONG LIVED AND AS
THICK AS DURING THE MORNING...BUT WIDESPREAD IFR VISIBILITIES
FROM 06Z- 14Z. AT TIMES VISIBILITIES VLIFR. RAPID IMPROVEMENT AFTER
SUNRISE WITH VISIBILITIES P6SM BY 16Z.
OTHERWISE...EITHER NO CEILINGS OR CEILINGS ABOVE 10 THOUSAND FEET.
WINDS TOO LIGHT TO AFFECT OPERATIONS.
&&
.IND WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...JH
NEAR TERM...JH
SHORT TERM...JH
LONG TERM....CP
AVIATION...JK
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
327 PM EST THU FEB 2 2012
.UPDATE...
THE AVIATION SECTION HAS BEEN UPDATED BELOW.
&&
.SYNOPSIS...
HIGH PRESSURE OVER NORTHERN INDIANA AND THE SOUTHERN GREAT LAKES
WILL CONTINUE MOVING EAST. MEANWHILE AN UPPER TROUGH OVER THE
CENTRAL ROCKIES WILL DEVELOP INTO A CLOSED UPPER LOW AND MOVE OUR
WAY SATURDAY AND SATURDAY NIGHT. A SURFACE LOW PRESSURE SYSTEM WILL
TRACK ACROSS KENTUCKY AND TENNESSEE SATURDAY AND SATURDAY NIGHT.
HIGH PRESSURE BEHIND THIS SYSTEM WILL BUILD OUR WAY LATE SUNDAY AND
MONDAY. IN THE EXTENDED HIGH PRESSURE WILL DOMINATE OUR WEATHER.
HOWEVER A WEAK AND DRY COLD FRONT WILL MOVE ACROSS OUR REGION AROUND
THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /TONIGHT/...
AREAS OF FOG AND STRATUS EARLIER OVER THE WESTERN PART OF OUR REGION
HAS TAKEN MOST OF THE DAY TO CLEAR OUT. HIGH PRESSURE WILL BRING
LIGHT WINDS AND MOSTLY CLEAR SKIES EARLY ON AND THERE IS SOME
POTENTIAL FOG SOME FOG AGAIN TONIGHT. ON THE OTHER HAND...THERE
WILL BE MORE CIRRUS MOVING IN OVERNIGHT WHICH WOULD LESSEN THE
POTENTIAL FOR FOG. THE 15Z VSREF SHOWS PRACTICALLY NO POTENTIAL FOR
FOG...WHILE THE RUC SOUNDINGS INDICATE A MUCH GREATER POTENTIAL FOG
FOG. THE WINDS AND CLOUDS LATER TONIGHT WILL LESSEN THE POTENTIAL
QUITE A BIT. BUT WITH SOME UNCERTAINTY WILL MENTION PATCHY FOG MOST
AREAS LATE TONIGHT. I DON`T THINK THERE WILL BE WIDESPREAD DENSE
FOG AS THERE WAS LAST NIGHT.
WITH CLEAR SKIES AND LIGHT WINDS WILL UNDERCUT MOS TEMPERATURES A
LITTLE TONIGHT. MOST AREAS LAST NIGHT ENDED SEVERAL DEGREES COOLER.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
THE HIGHEST DEWPOINTS AND LIGHTEST WINDS WILL BE ACROSS OUR NORTH
AND NORTHEAST SECTIONS FRIDAY MORNING. WILL MENTION SOME PATCHY FOG
ALL BUT FAR SOUTHWEST EARLY FRIDAY. OTHERWISE...FRIDAY WILL BE
ANOTHER VERY NICE DAY WITH INCREASING HIGH CLOUDS. WENT CLOSE TO A
MET/MAV BLEND ON TEMPERATURES.
ALL MODELS SPREAD RAIN INTO OUR REGION FRIDAY NIGHT AND SATURDAY
APPEARS TO BE A VERY WET DAY WITH PERIODS OF RAIN MOST AREAS. BUT
WITH SLIGHTLY LESSER CHANCES ACROSS OUR FAR NORTH. AS FAR AS
TEMPERATURES WENT SLIGHTLY ABOVE MAV/MET BLEND FRIDAY NIGHT AND
SLIGHTLY BELOW SATURDAY AS CLOUDS AND PRECIP SHOULD LIMIT ANY
DIURNAL TREND ON TEMPERATURES.
1000 TO 850 MB THICKNESS DROP TO NEAR OR SLIGHTLY BELOW 1300 METERS
LATE SATURDAY NIGHT ACROSS OUR NORTH AND WILL MENTION CHANCE OF
MIXED PRECIP THERE. BUT IT IS POSSIBLE THE PRECIP MAY BE OVER
ACROSS OUR NORTH BY THAT TIME.
MODELS START TO MOVE THE UPPER LOW TO THE SOUTHEAST AS AN UPPER
RIDGE DEVELOPS OVER THE NORTHERN PLAINS. JUST ABOUT ALL MODELS NOW
LEAN TOWARDS A DRY DAY SUNDAY. BUT WITH AN UPPER TROUGH STILL OVER
OUR REGION 12Z-18Z SUNDAY...I AM STILL A BIT RELUCTANT TO JUMP ON
THE DRY BAND WAGON YET SUNDAY WITH THE POSSIBLE EXCEPTION OF OUR
NORTHERN AREAS WOULD DRY OUT FIRST. EITHER CASE...ANY REMAINING
PRECIP WILL END DURING THE DAY SUNDAY AS THE UPPER TROUGH MOVES TO
THE SOUTHEAST. DID NOT MAKE ANY SIGNIFICANT CHANGES TO TEMPERATURES
SUNDAY.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
QUIET PATTERN FOR THE LONG TERM. MODELS ARE MOVING THE TROUGH AXIS
THROUGH A LITTLE BIT FASTER SUNDAY SO BY SUNDAY NIGHT IT LOOKS LIKE
ALL PRECIP SHOULD HAVE MOVED OUT OF THE AREA. WITH THE VESTIGES OF
AN UPPER LOW STILL HANGING AROUND UPSTREAM AND MOVING ACROSS ON
MONDAY COULD SEE A LITTLE INCREASED CLOUD COVER BUT THAT/S IT GIVEN
THE LACK OF MOISTURE AND LACK OF FORCING. AFTER THAT MOVES THROUGH
MONDAY UPPER FLOW INCLUDES A DEEP UPPER LOW MOVING INTO ST JAMES BAY
AND ANOTHER UPPER LOW DIGGING INTO WESTERN MEXICO BUT VERY LITTLE
GOING ON ELSEWHERE. TEMPERATURES LOOK A LITTLE WARMER THAN AVERAGE
FOR THIS TIME OF YEAR BUT ALLBLEND CAPTURED THIS WELL. ONLY CHANGES
TO ALLBLEND FOR POPS WAS TO REMOVE SLIGHT CHANCE IN THE SOUTH ON
SUNDAY NIGHT DUE TO FASTER MOVEMENT OF THE TROUGH AND REMOVAL OF
SLIGHT CHANCE POPS IN DAY 7 WITH ENSEMBLES AND OPERATIONAL GFS
FAVORING DRY.
&&
.AVIATION /DISCUSSION FOR 02/21Z IND TAF UPDATE/...
CHANGED WINDS TO VARIABLE AT IND AS HIGH PRESSURE IS RIGHT OVERHEAD
AND DIRECTION COULD CHANGE SIGNIFICANTLY AT ANY GIVEN TIME. WINDS
SHOULD BE AROUND 5-7KT OR LESS...SO SHOULD NOT CAUSE MAJOR PROBLEMS.
PREVIOUS DISCUSSION FOLLOWS.
ANY LEFTOVER FOG/STRATUS AT THE SITES SHOULD RAPIDLY BURN OFF WITHIN
AN HOUR OF ISSUANCE TIME AT KHUF AND KBMG. KIND AND KLAF HAVE
ALREADY COME UP TO MVFR AND WILL LIKELY BE VFR BY ISSUANCE TIME AND
WILL REMAIN THAT WAY THROUGH THE DAY. WINDS WILL BE LIGHT /AROUND 5
KTS OR SO/ THROUGH THE DAY AND WILL DROP TO EVEN LIGHTER...PERHAPS
CALM...DURING THE OVERNIGHT.
SIGNIFICANT UNCERTAINTY EXISTS FOR EARLY TOMORROW MORNING REGARDING
THE DEVELOPMENT OF DENSE FOG. FORECAST SOUNDINGS LOOK SIMILAR TO
THIS MORNING AT THE LOW LEVELS WHICH PRODUCED DENSE FOG THAT LASTED
SEVERAL HOURS. HOWEVER THEY ALSO SHOW CIRRUS MOVING IN TONIGHT AND
THIS COULD SERVE TO DECREASE OVERNIGHT COOLING AND KEEP VISIBILITIES
FROM DROPPING TOO FAR. BASED ON THE POSITION OF THE UPPER RIDGE AND
JET IN RELATION TO THE CURRENT CIRRUS DECK UPSTREAM AND THE FORECAST
MOVEMENT OF THESE FEATURES THINK THE THICKER CIRRUS HERE OVERNIGHT
IS REASONABLE. THUS THINK BEST COURSE OF ACTION AT THIS TIME IS TO
INCLUDE IFR FOG FOR TOMORROW AND MONITOR SATELLITE CLOSELY TONIGHT
FOR POSITION AND NATURE OF CIRRUS AND ADJUST FORECAST ACCORDINGLY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...JH
NEAR TERM...JH
SHORT TERM...JH
LONG TERM....CP
AVIATION...CP/NIELD
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
320 PM EST THU FEB 2 2012
.UPDATE...
SYNOPSIS...NEAR TERM...SHORT TERM AND LONG TERM SECTIONS HAVE BEEN
UPDATED BELOW.
&&
.SYNOPSIS...
HIGH PRESSURE OVER NORTHERN INDIANA AND THE SOUTHERN GREAT LAKES
WILL CONTINUE MOVING EAST. MEANWHILE AN UPPER TROUGH OVER THE
CENTRAL ROCKIES WILL DEVELOP INTO A CLOSED UPPER LOW AND MOVE OUR
WAY SATURDAY AND SATURDAY NIGHT. A SURFACE LOW PRESSURE SYSTEM WILL
TRACK ACROSS KENTUCKY AND TENNESSEE SATURDAY AND SATURDAY NIGHT.
HIGH PRESSURE BEHIND THIS SYSTEM WILL BUILD OUR WAY LATE SUNDAY AND
MONDAY. IN THE EXTENDED HIGH PRESSURE WILL DOMINATE OUR WEATHER.
HOWEVER A WEAK AND DRY COLD FRONT WILL MOVE ACROSS OUR REGION AROUND
THE MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /TONIGHT/...
AREAS OF FOG AND STRATUS EARLIER OVER THE WESTERN PART OF OUR REGION
HAS TAKEN MOST OF THE DAY TO CLEAR OUT. HIGH PRESSURE WILL BRING
LIGHT WINDS AND MOSTLY CLEAR SKIES EARLY ON AND THERE IS SOME
POTENTIAL FOG SOME FOG AGAIN TONIGHT. ON THE OTHER HAND...THERE
WILL BE MORE CIRRUS MOVING IN OVERNIGHT WHICH WOULD LESSEN THE
POTENTIAL FOR FOG. THE 15Z VSREF SHOWS PRACTICALLY NO POTENTIAL FOR
FOG...WHILE THE RUC SOUNDINGS INDICATE A MUCH GREATER POTENTIAL FOG
FOG. THE WINDS AND CLOUDS LATER TONIGHT WILL LESSEN THE POTENTIAL
QUITE A BIT. BUT WITH SOME UNCERTAINTY WILL MENTION PATCHY FOG MOST
AREAS LATE TONIGHT. I DON`T THINK THERE WILL BE WIDESPREAD DENSE
FOG AS THERE WAS LAST NIGHT.
WITH CLEAR SKIES AND LIGHT WINDS WILL UNDERCUT MOS TEMPERATURES A
LITTLE TONIGHT. MOST AREAS LAST NIGHT ENDED SEVERAL DEGREES COOLER.
&&
.SHORT TERM /FRIDAY THROUGH SUNDAY/...
THE HIGHEST DEWPOINTS AND LIGHTEST WINDS WILL BE ACROSS OUR NORTH
AND NORTHEAST SECTIONS FRIDAY MORNING. WILL MENTION SOME PATCHY FOG
ALL BUT FAR SOUTHWEST EARLY FRIDAY. OTHERWISE...FRIDAY WILL BE
ANOTHER VERY NICE DAY WITH INCREASING HIGH CLOUDS. WENT CLOSE TO A
MET/MAV BLEND ON TEMPERATURES.
ALL MODELS SPREAD RAIN INTO OUR REGION FRIDAY NIGHT AND SATURDAY
APPEARS TO BE A VERY WET DAY WITH PERIODS OF RAIN MOST AREAS. BUT
WITH SLIGHTLY LESSER CHANCES ACROSS OUR FAR NORTH. AS FAR AS
TEMPERATURES WENT SLIGHTLY ABOVE MAV/MET BLEND FRIDAY NIGHT AND
SLIGHTLY BELOW SATURDAY AS CLOUDS AND PRECIP SHOULD LIMIT ANY
DIURNAL TREND ON TEMPERATURES.
1000 TO 850 MB THICKNESS DROP TO NEAR OR SLIGHTLY BELOW 1300 METERS
LATE SATURDAY NIGHT ACROSS OUR NORTH AND WILL MENTION CHANCE OF
MIXED PRECIP THERE. BUT IT IS POSSIBLE THE PRECIP MAY BE OVER
ACROSS OUR NORTH BY THAT TIME.
MODELS START TO MOVE THE UPPER LOW TO THE SOUTHEAST AS AN UPPER
RIDGE DEVELOPS OVER THE NORTHERN PLAINS. JUST ABOUT ALL MODELS NOW
LEAN TOWARDS A DRY DAY SUNDAY. BUT WITH AN UPPER TROUGH STILL OVER
OUR REGION 12Z-18Z SUNDAY...I AM STILL A BIT RELUCTANT TO JUMP ON
THE DRY BAND WAGON YET SUNDAY WITH THE POSSIBLE EXCEPTION OF OUR
NORTHERN AREAS WOULD DRY OUT FIRST. EITHER CASE...ANY REMAINING
PRECIP WILL END DURING THE DAY SUNDAY AS THE UPPER TROUGH MOVES TO
THE SOUTHEAST. DID NOT MAKE ANY SIGNIFICANT CHANGES TO TEMPERATURES
SUNDAY.
&&
LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
QUIET PATTERN FOR THE LONG TERM. MODELS ARE MOVING THE TROUGH AXIS
THROUGH A LITTLE BIT FASTER SUNDAY SO BY SUNDAY NIGHT IT LOOKS LIKE
ALL PRECIP SHOULD HAVE MOVED OUT OF THE AREA. WITH THE VESTIGES OF
AN UPPER LOW STILL HANGING AROUND UPSTREAM AND MOVING ACROSS ON
MONDAY COULD SEE A LITTLE INCREASED CLOUD COVER BUT THAT/S IT GIVEN
THE LACK OF MOISTURE AND LACK OF FORCING. AFTER THAT MOVES THROUGH
MONDAY UPPER FLOW INCLUDES A DEEP UPPER LOW MOVING INTO ST JAMES BAY
AND ANOTHER UPPER LOW DIGGING INTO WESTERN MEXICO BUT VERY LITTLE
GOING ON ELSEWHERE. TEMPERATURES LOOK A LITTLE WARMER THAN AVERAGE
FOR THIS TIME OF YEAR BUT ALLBLEND CAPTURED THIS WELL. ONLY CHANGES
TO ALLBLEND FOR POPS WAS TO REMOVE SLIGHT CHANCE IN THE SOUTH ON
SUNDAY NIGHT DUE TO FASTER MOVEMENT OF THE TROUGH AND REMOVAL OF
SLIGHT CHANCE POPS IN DAY 7 WITH ENSEMBLES AND OPERATIONAL GFS
FAVORING DRY.
&&
.AVIATION /DISCUSSION FOR 021800Z TAF ISSUANCE/...
ANY LEFTOVER FOG/STRATUS AT THE SITES SHOULD RAPIDLY BURN OFF WITHIN
AN HOUR OF ISSUANCE TIME AT KHUF AND KBMG. KIND AND KLAF HAVE
ALREADY COME UP TO MVFR AND WILL LIKELY BE VFR BY ISSUANCE TIME AND
WILL REMAIN THAT WAY THROUGH THE DAY. WINDS WILL BE LIGHT /AROUND 5
KTS OR SO/ THROUGH THE DAY AND WILL DROP TO EVEN LIGHTER...PERHAPS
CALM...DURING THE OVERNIGHT.
SIGNIFICANT UNCERTAINTY EXISTS FOR EARLY TOMORROW MORNING REGARDING
THE DEVELOPMENT OF DENSE FOG. FORECAST SOUNDINGS LOOK SIMILAR TO
THIS MORNING AT THE LOW LEVELS WHICH PRODUCED DENSE FOG THAT LASTED
SEVERAL HOURS. HOWEVER THEY ALSO SHOW CIRRUS MOVING IN TONIGHT AND
THIS COULD SERVE TO DECREASE OVERNIGHT COOLING AND KEEP VISIBILITIES
FROM DROPPING TOO FAR. BASED ON THE POSITION OF THE UPPER RIDGE AND
JET IN RELATION TO THE CURRENT CIRRUS DECK UPSTREAM AND THE FORECAST
MOVEMENT OF THESE FEATURES THINK THE THICKER CIRRUS HERE OVERNIGHT
IS REASONABLE. THUS THINK BEST COURSE OF ACTION AT THIS TIME IS TO
INCLUDE IFR FOG FOR TOMORROW AND MONITOR SATELLITE CLOSELY TONIGHT
FOR POSITION AND NATURE OF CIRRUS AND ADJUST FORECAST ACCORDINGLY.
&&
.IND WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SYNOPSIS...JH
NEAR TERM...JH
SHORT TERM...JH
LONG TERM....CP
AVIATION...CP
AREA FORECAST DISCUSSION
NWS DES MOINES IA
335 PM CST THU FEB 2 2012
.SHORT TERM /TONIGHT/...
COMPLICATED FORECAST TONIGHT ALBEIT A DRY ONE. FOG WAS SLOW TO BURN
OFF TODAY ACROSS THE NORTHEAST AND MOISTURE REMAINS JUST TO OUR
EAST. LOW LEVEL FLOW TONIGHT WILL BECOME EASTERLY AND ADVECT THE
MOISTURE/FOG BACK INTO THE AREA. I AM EXPECTING SIMILAR AREAS TO
HAVE DENSE FOG TONIGHT INTO FRIDAY MORNING AS WE DID LAST NIGHT.
THE QUESTION IS ONE OF TIMING AND EXTENT OF THE DENSE FOG. HRRR HAD
A DECENT HANDLE ON THE REDUCED VISIBILITIES BUT LIKE THIS MORNING...
IT WAS A BIT OVERDONE ON EXTENT. I USED TIMING SIMILAR TO THE HRRR
BUT EXTENT SIMILAR TO LAST NIGHT. TIME/HEIGHT CROSS SECTIONS
INDICATE DRY AIR JUST OFF THE SURFACE SO MOISTURE WON`T GET DEEP
ENOUGH TO PRODUCE PRECIP. WE ALSO DON`T HAVE ANY LIFT TO SPEAK OF
UNTIL FRIDAY MORNING. TONIGHTS LOW TEMPS WERE KEPT SIMILAR TO LAST
NIGHT.
.LONG TERM /FRIDAY THROUGH FRIDAY/...
COMPLICATED WEATHER SITUATION WITH THE LOW COMING OUT OF THE
ROCKIES. IN THE LONG WAVE PATTERN THE MEAN RIDGE POSITION IS IN THE
110W TO 115W AREA WITH THE MEAN TROUGH TO THE EAST IN THE 70W AREA.
LOW COMING OUT OF THE ROCKIES LIFTS NORTHEAST THEN TAKES A TURN TO
THE EAST AND EVENTUALLY EAST-SOUTHEAST AS IT MOVES PAST THE MEAN
RIDGE POSITION. THIS LENDS CREDIBILITY TO THE SOUTHWARD SHIFT IN
THE MODELS AND ALSO THE RAPID WEAKENING AS THE SYSTEM MOVES EAST.
THE SNOWFALL MAY WELL LOOK SOMEWHAT SIMILAR TO THE STORM SYSTEM A
FEW WEEKS BACK THAT DROPPED THE HEAVY SNOWFALL IN KS. A COUPLE
ANALOG CASES STAND OUT TODAY WITH ONE BEING THE EVENT AROUND 21 JAN
1990...THOUGH SHIFTED A WAYS FARTHER SOUTH...THE OTHER THE EVENT
AROUND 22 MAR 2006. IN BOTH CASES THE SYSTEM WEAKENED AS IT MOVED
EAST WITH MUCH OF THE HEAVY SNOW REMAINING WEST OF THE MO RIVER.
SEE A SIMILAR SITUATION HERE. INITIALLY DRY LOW LEVEL AIR WILL
INHIBIT PRECIP DEVELOPMENT. THE UPPER LOW AND STRONG DYNAMICS WILL
OVERCOME THAT WITH THE COLUMN SATURATING OVER THE CENTRAL AND SOUTH
BY FRI EVENING. PRECIPITATION WILL INITIALLY FALL AS RAIN WITH A
VERY GRADUAL CHANGE TO SNOW AS COLD AIR DEVELOPS AROUND THE CLOSED
LOW. SOME SLEET IS ALSO POSSIBLE ALONG THE NORTH EDGE OF THE PRECIP
AREA EARLY ON DUE TO A DECENT WARM LAYER...BUT EVAPORATIONAL COOLING
MAKING UP THE DIFFERENCE RESULTING IN RE-FREEZE. LOW WILL PULL TO
THE EAST SAT NIGHT WITH LAST OF THE SNOW ENDING ON SUN. BACKED OFF
A BIT ON THE WINTER STORM WATCH DUE TO UNANIMOUS SHIFT IN THE
MODELS. THINKING AT THIS POINT IS IF WINTER WINTER STORM CONDITIONS
ARE TO BE MET...IT WILL BE A MARGINAL CASE AND CURRENT ADJUSTMENTS
TO THE WATCH AREA INCLUDE ABOUT A COUNTY BUFFER TO AREA LIKELY TO
REACH CRITERIA. WINDS ARE NOT LIKELY TO BE A MAJOR FACTOR WITH THIS
SYSTEM...THOUGH MAY GUST TO 25 TO 30 MPH AT TIMES. BLOWING SNOW
WILL BE LIMITED BY THE SPRING TYPE NATURE OF THE SYSTEM. NO
SIGNIFICANT COOLING BEHIND THE STORM SYSTEM AS THE AIRMASS IS
PACIFIC IN NATURE. ARCTIC AIR IS EXPECTED TO REMAIN WELL TO THE
NORTHEAST OF IA. DRY WEATHER AS WE HEAD INTO NEXT WEEK WITH TEMPS
REMAINING ABOVE NORMAL BY A FEW DEGREES.
&&
.AVIATION...02/18Z
DENSE FOG STILL LINGERING NEAR KALO AND COULD PERSIST FOR SEVERAL
MORE HOURS WHICH WOULD LEAD TO EXTENSION ONE MORE TIME OF THE DENSE
FOG ADVISORY FOR KALO ONLY. MOISTURE IS NOT EXPECTED TO PUSH OFF
EAST AND WITH AN EASTERLY FLOW SETTING UP TONIGHT...EASTERN TAF
LOCATIONS SHOULD SEE THE FOG ADVECT BACK IN THIS EVENING. CURRENT
MODEL TRENDS HAVE THE SYSTEM TO AFFECT IOWA NOW MOVING SOUTH SO I
HAVE BACKED OFF ON TIMING OF PRECIP. IT SHOULD NOT AFFECT TAF
LOCATIONS THIS PERIOD THOUGH SHOWERS MAY BE CLOSE TO KDMX BY THE END
OF THE TAF PERIOD.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WATCH FROM FRIDAY EVENING THROUGH LATE SATURDAY
NIGHT FOR ADAIR-ADAMS-AUDUBON-CARROLL-CASS-CRAWFORD-DALLAS-
GREENE-GUTHRIE-MADISON-TAYLOR-UNION.
DENSE FOG ADVISORY FROM MIDNIGHT TONIGHT TO 10 AM CST FRIDAY FOR
DAVIS-JASPER-MAHASKA-MARION-MARSHALL-MONROE-POWESHIEK-TAMA-
WAPELLO.
DENSE FOG ADVISORY FROM 9 PM THIS EVENING TO 10 AM CST FRIDAY
FOR BLACK HAWK-BREMER-BUTLER-CERRO GORDO-FRANKLIN-GRUNDY-HANCOCK-
HARDIN-WINNEBAGO-WORTH.
&&
$$
SHORT TERM...FAB
LONG TERM...MS FEB 12
AVIATION...FAB
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
600 PM EST THU FEB 2 2012
.SYNOPSIS...
HIGH PRESSURE WILL BUILD OVER THE REGION KEEPING THE AREA DRY AND
UNSEASONABLY WARM THROUGH THE BEGINNING OF THE WEEKEND. A LOW
PRESSURE SYSTEM CROSSING THE CENTRAL PLAINS MAY BRING A SLIGHT CHANCE
OF RAIN AND SNOW SHOWERS SATURDAY NIGHT.
&&
.NEAR TERM /THROUGH FRIDAY/...
A FEW FLURRIES STILL LINGERING OVER PORTIONS OF CWA EAST OF
PITTSBURGH. SINCE THE HRRR ALSO INDICATED THIS SMALL CHANCE OF
PRECIPITATION...CONTINUED FLURRIES IN THE GRIDS THROUGH 9PM THIS
EVENING.
SKY WILL START TO CLEAR OUT OVERNIGHT AS HIGH PRESSURE APPROACHES
AND REMAINS IN CONTROL FRIDAY. FORECAST TEMPERATURES TO BE RIGHT
AROUND MOS GUIDANCE WHICH IS ROUGHLY 5-10 DEGREES ABOVE NORMAL.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
HIGH PRESSURE WILL BEGIN TO SLIDE TO THE COAST FRIDAY NIGHT AS AN
UPPER LEVEL WAVE EJECTS FROM THE ROCKIES WHILE ANOTHER TROUGH
DROPS SOUTH OVER THE GREAT LAKES. THIS SHOULD KEEP FRIDAY AND
SATURDAY DRY.
THE MODELS HAVE NOT HAD THE GREATEST HANDLE ON THIS SPLIT FLOW
PATTERN FOR MANY DAYS. HOWEVER...SIMILARITIES BETWEEN EACH MODEL
ARE EVIDENT. AT THIS POINT IT LOOKS LIKE THE TROUGH DROPPING OUT
OF THE GREAT LAKES WILL HELP TO MOVE THE LOW IN THE CENTRAL PLAINS
SOUTHEASTWARD KEEPING MOST OF THE PRECIPITATION SOUTH OF THE MASON
DIXON LINE. THERE WILL BE A TIGHT PRECIPITATION GRADIENT...JUST
WHERE EXACTLY IT WILL SET UP IS NOT QUITE CLEAR. OPTED TO REMAIN
CLOSEST TO THE 12Z NAM/GFS AND 00Z ECMWF BUT ALSO DID NOT DISCOUNT
THE 00Z GEFS. KEPT ONLY SLIGHT CHANCE POPS FOR SATURDAY NIGHT DUE
TO THE UNCERTAINTY AND MAINTAINED A MOS/NAM BLEND IN TEMPERATURES.
HIGH PRESSURE SHOULD ONCE AGAIN TAKE HOLD ON SUNDAY.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
A WEAK SURFACE RIDGE WILL MAINTAIN MAINLY DRY WEATHER THROUGH
MONDAY. LATEST MODEL RUNS PUSH A COLD FRONT ACROSS THE GREAT LAKES
ON TUESDAY. THIS SYSTEM WILL BRING SCATTERED SHOWERS INTO THE
REGION...FOLLOWED BY DRY CONDITIONS AS SURFACE HIGH PRESSURE BUILDS
IN FOR WEDNESDAY. TEMPERATURES ARE FORECAST TO REMAIN ABOVE NORMAL
THROUGH TUESDAY.
A NORTHERN BRANCH SHORT WAVE TROUGH AND ASSOCIATED COLD FRONT IS
PROGGED TO BRING SHOWERS AND A RETURN TO NEAR NORMAL TEMPERATURES BY
THURSDAY.
&&
.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
STRATOCUMULUS IS BEGINNING TO DISSIPATE FROM SOUTH TO NORTH. WHERE
CEILINGS EXIST...THEY ARE HIGH MVFR TO LOW VFR. CIGS SHOULD SCATTER
OUT DURING THE EVENING AT MOST SITES. LAMP IS THE ONLY GUIDANCE
INDICATING THAT MVFR CEILINGS WILL REMAIN OVERNIGHT AT FKL AND
DUJ...BUT THINK THAT THIS SCENARIO IS QUITE PLAUSIBLE. WILL KEEP
MVFR CIGS AT THE 2 NORTHERN SITES OVERNIGHT...FINALLY SCATTERING OUT
FRIDAY MORNING. WINDS WILL BECOME LIGHT AND VARIABLE AS HIGH
PRESSURE MOVES OVERHEAD...WITH LIGHT WEST WINDS EXPECTED TOMORROW IN
VFR CONDITIONS.
OUTLOOK...FRIDAY NIGHT THROUGH TUESDAY...
HIGH PRESSURE SHOULD PROVIDE GENERALLY VFR WEATHER THROUGH SATURDAY.
LATEST MODELS SHOW A LOW PRESSURE SYSTEM MOVING EASTWARD FROM THE
MISSOURI VALLEY TO THE SOUTHEAST COAST LATE SUNDAY INTO MONDAY.
IT APPEARS THAT THE BULK OF ASSOCIATED PRECIPITATION AND
RESTRICTIONS WILL REMAIN SOUTH OF OUR TERMINALS.
A COLD FRONT IS THEN PROGGED TO SWING ACROSS THE GREAT LAKES AND
BRING SCATTERED PRECIPITATION AND POSSIBLE RESTRICTIONS INTO THE
UPPER OHIO REGION TUESDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
334 PM EST THU FEB 2 2012
.SYNOPSIS...
HIGH PRESSURE WILL BUILD OVER THE REGION KEEPING THE AREA DRY AND
UNSEASONABLY WARM THROUGH THE BEGINNING OF THE WEEKEND. A LOW
PRESSURE SYSTEM CROSSING THE CENTRAL PLAINS MAY BRING A SLIGHT CHANCE
OF RAIN AND SNOW SHOWERS SATURDAY NIGHT.
&&
.NEAR TERM /THROUGH FRIDAY/...
A FEW FLURRIES HAVE DEVELOPED MAINLY OVER PORTIONS OF CWA NORTH OF
I-80. SINCE THE HRRR ALSO INDICATED THIS SMALL CHANCE OF
PRECIPITATION...PUT FLURRIES IN THE GRIDS THROUGH 7PM THIS
EVENING. CLOUD COVER WILL CONTINUE TO IMPACT THE REGION AS THE
UPPER LEVEL TROUGH CROSSES THE REGION. MODEL PROFILES CONTINUE TO
SUGGEST A GRADUALLY CLEARING FROM SOUTHWEST TO NORTHEAST BY
TONIGHT AS HIGH PRESSURE BUILDS OVERHEAD.
SKIES WILL CLEAR OUT OVERNIGHT AS HIGH PRESSURE APPROACHES AND
REMAINS IN CONTROL FRIDAY. FORECAST TEMPERATURES TO BE RIGHT
AROUND MOS GUIDANCE WHICH IS ROUGHLY 5-10 DEGREES ABOVE NORMAL.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
HIGH PRESSURE WILL BEGIN TO SLIDE TO THE COAST FRIDAY NIGHT AS AN
UPPER LEVEL WAVE EJECTS FROM THE ROCKIES WHILE ANOTHER TROUGH
DROPS SOUTH OVER THE GREAT LAKES. THIS SHOULD KEEP FRIDAY AND
SATURDAY DRY.
THE MODELS HAVE NOT HAD THE GREATEST HANDLE ON THIS SPLIT FLOW
PATTERN FOR MANY DAYS. HOWEVER...SIMILARITIES BETWEEN EACH MODEL
ARE EVIDENT. AT THIS POINT IT LOOKS LIKE THE TROUGH DROPPING OUT
OF THE GREAT LAKES WILL HELP TO MOVE THE LOW IN THE CENTRAL PLAINS
SOUTHEASTWARD KEEPING MOST OF THE PRECIPITATION SOUTH OF THE MASON
DIXON LINE. THERE WILL BE A TIGHT PRECIPITATION GRADIENT...JUST
WHERE EXACTLY IT WILL SET UP IS NOT QUITE CLEAR. OPTED TO REMAIN
CLOSEST TO THE 12Z NAM/GFS AND 00Z ECMWF BUT ALSO DID NOT DISCOUNT
THE 00Z GEFS. KEPT ONLY SLIGHT CHANCE POPS FOR SATURDAY NIGHT DUE
TO THE UNCERTAINTY AND MAINTAINED A MOS/NAM BLEND IN TEMPERATURES.
HIGH PRESSURE SHOULD ONCE AGAIN TAKE HOLD ON SUNDAY.
&&
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
A WEAK SURFACE RIDGE WILL MAINTAIN MAINLY DRY WEATHER THROUGH
MONDAY. LATEST MODEL RUNS PUSH A COLD FRONT ACROSS THE GREAT LAKES
ON TUESDAY. THIS SYSTEM WILL BRING SCATTERED SHOWERS INTO THE
REGION...FOLLOWED BY DRY CONDITIONS AS SURFACE HIGH PRESSURE BUILDS
IN FOR WEDNESDAY. TEMPERATURES ARE FORECAST TO REMAIN ABOVE NORMAL
THROUGH TUESDAY.
A NORTHERN BRANCH SHORT WAVE TROUGH AND ASSOCIATED COLD FRONT IS
PROGGED TO BRING SHOWERS AND A RETURN TO NEAR NORMAL TEMPERATURES BY
THURSDAY.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
BROKEN MVFR STRATOCUMULUS IS EXPECTED TO DISSIPATE THIS EVENING AS
SOMEWHAT DRIER AIR PUSHES IN WITH SURFACE HIGH PRESSURE. NORTHWEST
SURFACE WINDS AROUND 10KT ARE FORECAST TO BECOME LIGHT AND VARIABLE
TONIGHT. VFR CONDITIONS SHOULD PREVAIL ON FRIDAY.
OUTLOOK...FRIDAY NIGHT THROUGH TUESDAY...
HIGH PRESSURE SHOULD PROVIDE GENERALLY VFR WEATHER THROUGH SATURDAY.
LATEST MODELS SHOW A LOW PRESSURE SYSTEM MOVING EASTWARD FROM THE
MISSOURI VALLEY TO THE SOUTHEAST COAST LATE SUNDAY INTO MONDAY.
IT APPEARS THAT THE BULK OF ASSOCIATED PRECIPITATION AND
RESTRICTIONS WILL REMAIN SOUTH OF OUR TERMINALS.
A COLD FRONT IS THEN PROGGED TO SWING ACROSS THE GREAT LAKES AND
BRING SCATTERED PRECIPITATION AND POSSIBLE RESTRICTIONS INTO THE
UPPER OHIO REGION TUESDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
146 PM EST THU FEB 2 2012
.SYNOPSIS...
HIGH PRESSURE WILL BUILD OVER THE REGION KEEPING THE AREA DRY AND
UNSEASONABLY WARM THROUGH THE BEGINNING OF THE WEEKEND.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A FEW FLURRIES HAVE DEVELOPED MAINLY OVER PORTIONS OF CWA NORTH OF
I-80. SINCE THE HRRR ALSO INDICATED THIS SMALL CHANCE OF
PRECIPITATION...PUT FLURRIES IN THE GRIDS THROUGH 7PM THIS
EVENING. CLOUD COVER WILL CONTINUE TO IMPACT THE REGION AS THE
UPPER LEVEL TROUGH CROSSES THE REGION. MODEL PROFILES CONTINUE TO
SUGGEST A GRADUALLY CLEARING FROM SOUTHWEST TO NORTHEAST BY
TONIGHT AS HIGH PRESSURE BUILDS OVERHEAD.
NO OTHER CHANGES WERE NEEDED IN THE NEAR TERM PERIOD.&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
HIGH PRESSURE WILL SETTLE IN OVER THE ENTIRE UPPER OHIO VALLEY
THROUGH FRIDAY NIGHT WITH TEMPERATURES REMAINING 5 TO 10 DEGREES
ABOVE NORMAL.
MODELS ARE BEGINNING TO COME INTO BETTER AGREEMENT FOR SATURDAY.
DIFFICULT SCENARIO FOR MODELS TO GET A GOOD HANDLE ON AS THERE
AREA A LOT OF FACTORS INVOLVED.
SFC LOW WILL MOVE OUT OF WEST TX NORTHWARD AHEAD OF A DEEPENING UL
LOW OVER THE ROCKIES. AT THE SAME TIME, AN UL RIDGE WILL DEVELOP
OVER THE MIDWEST AND SFC HIGH WILL MOVE THROUGH THE UPPER OHIO
VALLEY.
BY SATURDAY MORNING, ENERGY FROM THE SYSTEM, WHICH WILL MOVE INTO
MO, WILL BEGIN TO SPLIT. PART OF THE SYSTEM WILL REMAIN OVER THE
ROCKIES WITH THE UL LOW, WHILE THE EASTERN PART OF THE SYSTEM WILL
SHIFT INTO THE TN VALLEY. THE SFC LOW WILL MOVE SLOWLY EASTWARD
SATURDAY, AND RAINFALL WILL SPREAD OVER THE MID-ATLANTIC AND LOWER
OHIO VALLEY ALONG A WARM FRONT. A STRONG SFC HIGH WILL MOVE
SOUTHWARD FROM SOUTHERN CANADA OVER THE EASTERN GREAT LAKES. THE
HIGH WILL SUPPRESS THE MOISTURE/PRECIPITATION WITH THE SOUTHERN
SYSTEM, KEEPING MOST OF THE AREA DRY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
A WEAK SURFACE RIDGE WILL MAINTAIN MAINLY DRY WEATHER THROUGH
MONDAY. LATEST MODEL RUNS PUSH A COLD FRONT ACROSS THE GREAT LAKES
ON TUESDAY. THIS SYSTEM WILL BRING SCATTERED SHOWERS INTO THE
REGION...FOLLOWED BY DRY CONDITIONS AS SURFACE HIGH PRESSURE BUILDS
IN FOR WEDNESDAY. TEMPERATURES ARE FORECAST TO REMAIN ABOVE NORMAL
THROUGH TUESDAY.
A NORTHERN BRANCH SHORT WAVE TROUGH AND ASSOCIATED COLD FRONT IS
PROGGED TO BRING SHOWERS AND A RETURN TO NEAR NORMAL TEMPERATURES BY
THURSDAY.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
BROKEN MVFR STRATOCUMULUS IS EXPECTED TO DISSIPATE THIS EVENING AS
SOMEWHAT DRIER AIR PUSHES IN WITH SURFACE HIGH PRESSURE. NORTHWEST
SURFACE WINDS AROUND 10KT ARE FORECAST TO BECOME LIGHT AND VARIABLE
TONIGHT. VFR CONDITIONS SHOULD PREVAIL ON FRIDAY.
OUTLOOK...FRIDAY NIGHT THROUGH TUESDAY...
HIGH PRESSURE SHOULD PROVIDE GENERALLY VFR WEATHER THROUGH SATURDAY.
LATEST MODELS SHOW A LOW PRESSURE SYSTEM MOVING EASTWARD FROM THE
MISSOURI VALLEY TO THE SOUTHEAST COAST LATE SUNDAY INTO MONDAY.
IT APPEARS THAT THE BULK OF ASSOCIATED PRECIPITATION AND
RESTRICTIONS WILL REMAIN SOUTH OF OUR TERMINALS.
A COLD FRONT IS THEN PROGGED TO SWING ACROSS THE GREAT LAKES AND
BRING SCATTERED PRECIPITATION AND POSSIBLE RESTRICTIONS INTO THE
UPPER OHIO REGION TUESDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
313 PM EST THU FEB 2 2012
.SYNOPSIS...
HIGH PRESSURE WILL BUILD IN FROM THE NORTH FRIDAY AND SETTLE OVER
THE REGION ON SATURDAY. AN AREA OF LOW PRESSURE WILL MOVE SOUTH OF THE
AREA SUNDAY AND MONDAY...DRAGGING A COLD FRONT ACROSS THE REGION BY
EARLY TUESDAY. HIGH PRESSURE WILL AGAIN BUILD OVER THE AREA WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
AS OF 315 PM THURSDAY...COLD FRONT MOVING DOWN THE COAST AS OF 20Z
WITH WIND BECOMING MORE NNW/N AND LOWER DEWPOINTS SURGING INTO THE
REGION. SCATTERED CUMULUS SHOULD DISSIPATE WITH LOSS OF HEATING
THIS EVENING LEAVING A MOSTLY CLEAR SKY. BOUNDARY LAYER MIXING
SHOULD HELP KEEP TEMPERATURES UP OVERNIGHT AND WENT SLIGHTLY ABOVE
MOS GUIDANCE FORECASTING MIN TEMPERATURES IN THE UPPER 30S TO
LOWER 40S. THIS SHOULD PRECLUDE FOG FORMATION.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
AS OF 315 PM THURSDAY...AS AXIS OF 1030+ MB HIGH PRESSURE WILL
SETTLE OVER THE EASTERN CAROLINAS ON FRIDAY. THIS WILL LEAD TO A
MORE SEASONABLE DAY TEMPERATURE-WISE UNDER MOSTLY SUNNY SKIES.
TEMPERATURES SHOULD RANGE IN THE LOWER 50S IMMEDIATE COAST TO THE
MIDDLE AND UPPER 50S INLAND. LIGHT NORTHEAST WINDS WILL PREVAIL.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
AS OF 230 PM THURS...CONTINUED BELOW AVERAGE CONFIDENCE IN THE
LONG TERM FORECAST AS MODELS NOT IN BEST AGREEMENT WITH TIMING OF
A COUPLE FRONTAL SYSTEMS PROGGED TO IMPACT THE REGION THIS WEEKEND
AND INTO EARLY NEXT WEEK. BLEND OF 12Z GFS/00Z ECMWF PREFERRED BY
HPC AND GENERALLY FOLLOWED A BLEND OF 12Z HPC GUIDANCE AND 00Z
ECMWF PROGS THROUGH THE PERIOD.
SURFACE HIGH PRESSURE SHIFTS OFFSHORE FRI NIGHT INTO SAT WITH WEAK
SHORTWAVE RIDGING BUILDING IN FROM THE WEST. SOUTHERLY RETURN FLOW
SETS UP SAT AFTERNOON INTO SAT NIGHT WITH WEAK SHOWERS EXPECTED
OVERNIGHT. A WEAK FRONTAL BOUNDARY WILL DRIFT SOUTH ACROSS EASTERN
NC SAT NIGHT. FLOW ALOFT FLATTENS TO ZONAL BY SAT NIGHT. A SURFACE LOW
WILL DEVELOP ACROSS THE SOUTHERN APPALACHIAN MOUNTAINS SAT
EVENING. A STRONG POSITIVELY TILTED UPPER LEVEL TROUGH WILL DIG
SOUTH ACROSS VA/NC SUN INTO SUN NIGHT AND WILL DRAG THE SURFACE
LOW ACROSS EASTERN NC SUN. MAINTAINED CHANCE POPS WITH QPF AROUND
A QUARTER TO HALF INCH.
CONSIDERABLE CHANGE BETWEEN THE 00Z AND 12Z ECMWF RUNS WITH THE
EARLY WEEK SCENARIO. 00Z ECMWF/12Z GFS BRINGS IN WEAK SURFACE
RIDGING FROM THE NORTH EARLY MON AS ANOTHER SURFACE LOW DEVELOPS
ALONG A STALLED FRONT WELL TO THE SOUTH...WHILE THE 12Z ECMWF
KEEPS THE LOW FORMATION MUCH FARTHER SOUTH WITH LITTLE IMPACT ON
THE REGIONS WEATHER. SINCE THE 12Z ECMWF APPEARS TO BE AN
OUTLIER...WILL MAINTAIN FORECAST MENTALITY WITHOUT 12Z ECMWF INPUT
AND CONTINUE SLIGHT CHANCE POPS MON INTO MON NIGHT. WEAK RIDGING
DEVELOPS AT THE SURFACE TUES INTO WEDNESDAY WITH ZONAL FLOW ALOFT.
TEMPS IN THE EXTENDED WILL BE NEAR NORMAL WITH HIGHS IN THE MID TO
UPPER 50S AND LOWS IN THE 30S. AGAIN TIMING OF THESE SYSTEMS ARE
IN FLUX AS MODELS STILL TRYING TO GRASP THE AMPLIFIED SPLIT FLOW
PATTERN WITH A REX BLOCK ACROSS THE WRN CONUS LATE THIS WEEK AND
INTO THE WEEKEND.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
SHORT TERM /THROUGH FRIDAY/
AS OF 315 PM THURSDAY...WITH FRONT NOW MOVING OFFSHORE...SCATTERED
CUMULUS WITH BASES AT OR ABOVE 5000 FEET ARE PREVAILING ACROSS
EASTERN NORTH CAROLINA. THINK THESE CUMULUS WILL DISSIPATE WITH
LOSS OF HEATING LATER THIS EVENING WITH GENERALLY CLEAR SKIES
OVERNIGHT. SUFFICIENT BOUNDARY LAYER MIXING SHOULD PREVENT MUCH IN
THE WAY OF FOG FORMATION TONIGHT. FRIDAY WILL BE MOSTLY SUNNY WITH
VFR CONDITIONS PREVAILING.
LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
AS OF 240 PM THURS...EXPECT VFR CONDITIONS FRI NIGHT THROUGH SAT WITH
HIGH PRES ACROSS THE REGION. EXPECT INCREASING MOISTURE ACROSS THE
AREA LATE SAT AND SAT NIGHT WITH A COLD FRONT PUSHING SOUTH ACROSS
EASTERN NC LATE SAT NIGHT. A PERIOD OF MVFR TO IFR CIGS EXPECTED
LATE SAT NIGHT INTO SUN WITH A STRONG LOW LEVEL INVERSION TRAPPING
MOISTURE NEAR THE SFC ALONG AND BEHIND THE FRONT. IMPROVING
CONDITIONS EXPECTED LATE IN THE WEEKEND HOWEVER ANOTHER SYSTEM
MOVES INTO THE AREA LATE MON INTO EARLY TUE WHICH COULD BRING
ANOTHER ROUND OF SUB VFR CONDITIONS. BELOW NORMAL CONFIDENCE
HOWEVER AS MODELS HANDLING THE TIMING OF THE SYSTEMS DIFFERENTLY.
&&
.MARINE...
SHORT TERM /THROUGH TONIGHT/...
AS OF 315 PM THURSDAY...HAVE MADE SOME CHANGES TO THE MARINE
FORECAST AT THIS UPDATE. BASED ON CURRENT OBSERVATIONS AND A AREA
OF PRESSURE RISES MOVING INTO THE NORTHERN MARINE ZONES...CONFIDENCE
IS GOOD THAT A PERIOD OF SMALL CRAFT CRITERIA WINDS WILL OCCUR ON
THE SOUNDS AND COASTAL WATERS NORTH OF CAPE LOOKOUT AT LEAST THRU
THIS EVENING. THIS IS ALSO VERIFIED BY THE LATEST 13KM RUC MODEL
WHICH SHOWS SOME 20 TO 25 KNOT WINDS OVER THE NEXT 3 HOURS OR
SO...THEN ANOTHER PERIOD OF 20 TO 25 KNOTS LATER TONIGHT. SEAS
WILL BUILD OVER THE COASTAL WATERS NORTH OF CAPE LOOKOUT AND
ESPECIALLY NORTH OF OCRACOKE AFTER MIDNIGHT TONIGHT WITH 6 FOOT
SEAS LIKELY...ESPECIALLY OVER THE OUTER REACHES OF THE COASTAL
WATERS INTO FRIDAY AFTERNOON. NAM INDICATES SOME ADDITIONAL
GUSTINESS...ESPECIALLY OVER NORTHERN WATERS DURING FRIDAY
AFTERNOON AS WELL. WILL RUN THE ADVISORY THRU EARLY EVENING FRIDAY
ALTHOUGH SOME AREAS...PARTICULARLY THE SOUNDS MAY BE ABLE TO BE
DROPPED EARLIER. TRENDED TOWARD THE WAVEWATCH 4 FOR SEAS AS THE
LATEST LOCAL SWAN APPEARED TO BUILD AND DISSIPATE THE WAVES A BIT
TOO QUICKLY...WHICH IS A COMMON BIAS IN THE MODEL.
LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
AS OF 250 PM THURS...SURFACE HIGH PRESSURE WILL SHIFT OFFSHORE FRI
NIGHT INTO SAT WITH WINDS SHIFTING NORTHEAST THEN EAST TO
SOUTHEAST BY SAT EVENING AND REMAINING 10 KNOTS OR LESS. SEAS WILL
REMAIN 2 TO 4 FT FRI NIGHT INTO SUN. A WEAK COLD FRONT WILL PUSH
SOUTH ACROSS THE NORTHERN WATERS SAT NIGHT AND INCREASE 10 TO 15
KNOTS OUT OF THE NORTH. SEAS WILL BUILD 3 TO 5 FT LATE SUN NIGHT ACROSS
THE CENTRAL AND NORTHERN WATERS ASSOCIATED WITH A TIGHTENING SURFACE
PRESSURE GRADIENT AND WINDS INCREASING TO NEAR 20 KNOTS.
CONSIDERABLE MODEL DISAGREEMENT MON NIGHT INTO TUES WITH LATEST
GUIDANCE. WILL HEDGE TOWARD PREVIOUS FORECAST AND 00Z ECMWF FOR
CONTINUITY. SWAN AND WAVEWATCH III WERE IN DECENT AGREEMENT
THROUGH THE PERIOD.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 PM TO 10 PM EST FRIDAY FOR
AMZ130-135-150-152-154-156.
&&
$$
SYNOPSIS...CTC
NEAR TERM...CTC
SHORT TERM...RF
LONG TERM...DAG
AVIATION...CTC/DAG
MARINE...CTC/DAG
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
332 PM CST THU FEB 2 2012
.SHORT TERM...TONIGHT THROUGH SUNDAY
FOG WILL BE THE PRIMARY FORECAST CHALLENGE TONIGHT THROUGH
TOMORROW AND THEN TEMPERATURES INTO THE WEEKEND. GFS/NAM/ECMWF/
GEM ARE IN GOOD AGREEMENT AND WILL USE A MODEL BLEND.
DENSE FOG HAS BEEN STATIONARY SINCE THIS MORNING ACROSS PORTIONS
OF THE SOUTHERN VALLEY AND NORTHWEST/WEST CENTRAL MN...WHEREAS
OTHER AREAS HAVE SEEN SOME IMPROVEMENT SINCE EARLY AFTERNOON. HIGH
LOW-LEVEL MOISTURE COMBINED WITH LITTLE TO NO WIND WILL ALLOW
CLEAR AREAS THIS AFTERNOON TO FILL IN QUITE RAPIDLY AFTER SUNSET.
LATEST HRRR MODEL RUN SHOWS VISIBILITY DROPPING TO BELOW 1/2 MILE
ACROSS MOST OF THE FORECAST AREA. WILL ISSUE A DENSE FOG ADVISORY
FOR AREAS ALONG AND SOUTHEAST OF A LINE FROM COOPERSTOWN TO GRAND
FORKS TO HALLOCK FROM 00 UTC TONIGHT UNTIL 15 UTC FRIDAY MORNING.
EXPECT PERIODS OF DENSE FOG WITH VISIBILITY REDUCTIONS TO NEAR
ZERO AT TIMES. TEMPERATURES WILL BE BELOW ZERO...SO SOME FREEZING
FOG IS POSSIBLE RESULTING IN SLICK SPOTS ON AREA ROADWAYS AND
SIDEWALKS...BUT LOW VISIBILITY IS THE GREATER HAZARD. MOTORISTS
SHOULD PREPARE FOR RAPIDLY CHANGING DRIVING CONDITIONS THROUGH
THE NIGHT. WITH FOG...TEMPERATURES WILL NOT DROP MUCH AND BOTTOM
OUT IN THE UPPER TEENS TO LOWER 20S.
AS SURFACE HIGH PRESSURE PERSISTS ACROSS THE NORTHERN PLAINS...
WINDS WILL REMAIN LIGHT AND FOG MAY BE VERY SLOW TO DISSIPATE
DURING THE DAY ON FRIDAY. BECAUSE OF THIS...INCREASED SKY COVER
AND LOWERED TEMPERATURES WITH HIGHS AROUND 30 DEGREES. SURFACE
HIGH CENTER MOVES TO THE SOUTH FOR THE WEEKEND...INCREASING THE
PRESSURE GRADIENT ACROSS THE FORECAST AREA. WESTERLY WINDS WILL
INCREASE FROM 5 TO 10 MPH...WHICH SHOULD BE ENOUGH TO LIMIT
ADDITIONAL FOG FORMATION...BUT THIS IS SOMETHING TO WATCH.
ASSUMING LESS FOG...MORE SUN AND A WARMING WESTERLY WIND...
TEMPERATURES SATURDAY AND SUNDAY SHOULD CLIMB INTO THE MID TO
UPPER 30S EACH DAY. SUNDAY IN PARTICULAR MAY BE QUITE WARM WITH
SOME AREAS REACHING INTO THE 40S.
.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY
MODELS ARE IN GOOD OVERALL AGREEMENT WITH THE GFS A BIT MORE
CONSISTENT WITH COOL DOWN NEXT WEEK. THE OVERALL QUIET WEATHER
PATTERN CONTINUES WITH TEMPERATURES COOLING BELOW NORMAL BY NEXT
THU. WILL CONTINUE WITH A DRY FORECAST AS A COLD FRONT AND NW FLOW
ALOFT MOVE INTO THE NORTHERN PLAINS.
&&
.AVIATION...
EXPECT FOG AND LOW CLOUDS TO DEVELOP ONCE AGAIN OVERNIGHT. AFTER
SUNSET...EXPECT IFR/LIFR CONDITIONS TO DEVELOP WITH DENSE FOG ONCE
AGAIN. GIVEN THE LIGHT SFC WIND FLOW...THESE CONDITIONS WILL LIKELY
PERSIST THROUGH FRI MORNING AT LEAST.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...DENSE FOG ADVISORY UNTIL 10 AM CST FRIDAY FOR NDZ027>030-038-039-
049-052-053.
MN...DENSE FOG ADVISORY UNTIL 10 AM CST FRIDAY FOR MNZ001>009-013>017-
022>024-027>032-040.
&&
$$
ROGERS/DK
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
1004 AM CST THU FEB 2 2012
.DISCUSSION...
FOG CHALLENGES ABOUND. 15 UTC OBSERVATIONS SHOW MOST LOCATIONS
ACROSS NORTHWEST AND WEST CENTRAL MN STILL AT OR BELOW 1/4 MILE IN
DENSE FREEZING FOG. SOME SPOTS ACROSS EASTERN ND ARE BEGINNING TO
IMPROVE...BUT LATEST HRRR MODEL RUN SHOWS VISIBILITY AT OR BELOW
ONE HALF MILE ACROSS MUCH OF THE FORECAST AREA INTO THE EARLY
AFTERNOON. THIS SEEMS REASONABLE GIVEN LITTLE TO NO WIND AND WILL
EXTEND CURRENT FREEZING FOG ADVISORY UNTIL 1 PM CST. VISIBILITY
WILL IMPROVE INTO THE EARLY AFTERNOON...WITH SOME PATCHY FOG
POSSIBLE THROUGH THE REST OF THE DAY. WILL CANCEL THE ADVISORY
EARLY IF NEEDED.
TEMPERATURES ARE HIGHLY DEPENDENT ON FOG. ADJUSTED HOURLY CURVE TO
REFLECT A SLOWER REBOUND GIVEN PERSISTENT FOG...BUT COULD SEE HOUR
OVER HOUR RISES OF SEVERAL DEGREES ONCE FOG DISSIPATES. STILL
QUITE A BIT OF UNCERTAINTY WITH FORECAST HIGHS...SO DID NOT MAKE
ANY CHANGES FROM PREVIOUS SHIFT. ONCE FOG IS GONE...WILL STILL SEE
SOME MID-HIGH LEVEL CLOUD COVER FOR PARTLY SUNNY SKIES.
&&
.AVIATION...
AREAS OF DENSE FOG AT KTVF AND KBJI WILL BE SLOW TO DISSIPATE AND
DO NOT EXPECT IMPROVED CONDITIONS UNTIL AFTER 18 UTC. FOR KGFK AND
KFAR...BEGINNING TO SEE IMPROVED VISIBILITY AND THIS SHOULD
CONTINUE AS FOG/LOW CLOUDS LIFT LATE THIS MORNING. VFR CONDITIONS WILL
PERSIST AT KDVL. LIGHT AND VARIABLE WIND WILL BE THE RULE THROUGH
THE REST OF THE DAY.
&&
.PREV DISCUSSION... /ISSUED 430 AM CST THU FEB 2 2012/
SHORT TERM...TODAY THROUGH SATURDAY NIGHT.
MODEL ARE IN REASONABLE AGREEMENT THROUGH 84 HOURS. DIFFERENCE WITH
TIMING OF SHORT WAVES IN NORTHERN STREAM ACROSS CENTRAL CANADA.
OTHERWISE GOOD AGREEMENT OVER THE STATES. WILL USE A COMBINATION OF
GFS AND ECMWF.
UPPER AIR PATTERN FORECAST TO AMPLIFY WITH RIDGE BUILDING OVER
WESTERN NORTH AMERICA AND A TROUGH DIGGING OVER THE DESERT
SOUTHWEST. PATTERN PROGRESSES SLOWLY EAST INTO THE PLAINS BY 84 HOURS
IN A REX LIKE PATTERN.
OBSERVED AREA SOUNDINGS INDICATE INVERSION AND TRAPPED LOW LEVEL
MOISTURE OVER EASTERN ZONES IN A SLIGHTLY BACKED FLOW. MODEL
SOUNDINGS MAINTAIN THIS TRAPPED MOISTURE AND BACKED FLOW THROUGH FRI
UNDER LIGHT WINDS ALOFT. UPPER LEVEL RIDGE FORECAST TO MOVE INTO THE
REGION BY THE END OF THE PERIOD WHICH WILL INCREASE TEMPS ALOFT AND
SERVE ONLY TO ENHANCE THE INVERSION. CONCURRENTLY MODELS FORECAST LOW
LEVEL WINDS TO INCREASE AFTER FRI AND DRY OUT THE LOW LEVEL PROFILE.
WILL KEEP CLOUDS, PATCHY FOG, AND LOWER TEMPS OVER EASTERN ZONES
THRU AT LEAST FRI.
FIG LOOP SHOWED FOG CONTINUED TO EXPAND OVER NORTHWEST MN AND OVER
PARTS OF THE SOUTHWEST ZONES AND OVER PARTS OF NORTHEAST ND. WILL
EXPAND FREEZING FOG ADVISORY TO COVER MUCH OF THE AREA.
LONG TERM...SUNDAY THROUGH WEDNESDAY.
MODELS IN FAIR AGREEMENT WITH THE LONG TERM AS THE NORTHERN PLAINS
REMAINS BETWEEN THE CUT OFF 500MB LOW IN THE CENTRAL PLAINS AND
AMPLIFIED RIDGING IN CANADA...THE CENTER OF THE HIGH IN REX BLOCKISH
PATTERN. ALL MODELS KEEPING CENTRAL PLAINS CUT OFF PRECIP SOUTH OF
FA AND DRY THROUGH THE EXTENDED. THICKNESS SLOWLY LOWER TOWARD THE
MIDDLE OF NEXT WEEK AS RIDGING BREAKS DOWN AND MORE N TO NW 500MB
FLOW SETS UP...THAT SAID...TEMPS WILL COOL TOWARD THE MIDDLE OF THE
WEEK HOWEVER STILL ABOVE NORMAL FOR THE PERIOD.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...FREEZING FOG ADVISORY UNTIL 1 PM CST THIS AFTERNOON FOR NDZ008-
016-027>030-038-039-049-052-053.
MN...FREEZING FOG ADVISORY UNTIL 1 PM CST THIS AFTERNOON FOR
MNZ001>009-013>017-022>024-027>032-040.
&&
$$
ROGERS/HOPPES
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1223 PM EST THU FEB 2 2012
.SYNOPSIS...
A COLD FRONT WILL SWING ACROSS THE AREA THIS MORNING AND OFFSHORE
THIS AFTERNOON. HIGH PRESSURE BUILDS IN BEHIND THE FRONT LATER
TODAY BRINGING DRIER AND SOMEWHAT COOLER WEATHER FOR THE END OF
THE WORK WEEK. AN AREA OF LOW PRESSURE FROM THE MIDWEST PROVIDES
THE NEXT CHANCE FOR RAIN THIS WEEKEND.
&&
.NEAR TERM /UNTIL 7 PM THIS EVENING/...
AS OF 1010 AM EST THURSDAY...
ONLY A FEW SPRINKLES OR A RAIN SHOWER REMAINS ACROSS SE WEST
VA...WHICH SHOULD DECAY IN THE NEXT HOUR OR SO...MAYBE PROVIDING A
SHOWER INTO CRAIG AND NORTHERN ROANOKE COUNTY AS IT MOVES SE. DRIER
AIR WILL EFFICIENTLY MIX OUT CLOUDS WITH SUNSHINE JUST ABOUT CWA
WIDE INTO THE AFTERNOON. WITH THAT...WINDS MAY GUST TO 30 MPH AT
TIMES ACROSS THE RIDGES.
AS OF 402 AM EST THURSDAY...
BASED ON REPORTS OF FOG BEING MORE WIDESPREAD...DECIDED TO GO AHEAD
WITH A SHORT TERM DENSE FOG ADVISORY FOR A STRIP RIGHT ALONG THE
BLUE RIDGE GIVEN PERSISTENT VSBYS AOB 1/4 MILE FROM WILKES UP TO
PATRICK CTY. EXPECT WINDS TO QUICKLY MIX THE FOG OUT AFTER SUNRISE
WHEN SHOULD BE ABLE TO CANCEL BUT LIKELY ENOUGH OF A PROBLEM FOR
THE EARLY COMMUTE TO GO WITH THE ADVISORY AT THIS POINT. NO OTHER
CHANGES FOR NOW.
AS OF 255 AM EST THURSDAY...
COLD FRONT AND ASSOCIATED AREAS OF LOW PRESSURE WILL SWING EAST
CROSSING THE MOUNTAINS EARLY THIS MORNING AND THE PIEDMONT BY
MIDDAY. BAND OF CONVECTION JUST AHEAD OF THE WAVE(S) IN
CONJUNCTION WITH A SMALL COMMA HEAD FEATURE UNDER THE UPPER VORT
LOBE MAY USHER IN GROUNDHOG DAY OVER THE NW WITH A RUMBLE OF
THUNDER EARLY THIS MORNING. THIS IN LINE WITH THE LATEST HRRR AND
LOCAL RNK WRF WHICH PUSH THIS FEATURE ACROSS THE GREENBRIER
VALLEY/HIGHLANDS EARLY ON BEFORE WEAKENING HEADING EAST OF THE
RIDGES BY MID MORNING. IN BETWEEN MAY SEE ONLY SCTD SHRA AS THE
TRAILING AXIS TENDS TO SPLIT BUT EXPECT SOME ADDED SHRA BANDS WEST
AS THE FLOW TURNS MORE NW THRU MIDDAY. THUS WILL CARRY LIKELY POPS
ACROSS THE NW/NORTH AND FAR WEST EARLY THIS MORNING...TAPERING TO
CHANCE ELSW AND BASICALLY DRY AFTER EARLY AFTERNOON WITH DRYING
BEHIND THE PASSING FRONT. FOG ANOTHER ISSUE EARLY ON ACROSS THE SW
WHERE SOME CLEARING HAS LEAD TO POCKETS OF VERY DENSE FOG WHICH
CONTINUE TO COVER WITH AN SPS FOR NOW. EXPECT MIXING TO HELP
CLEANSE THINGS OUT TOWARD DAYBREAK AS THE FRONT ARRIVES. OTRW
LOOKING FOR GRADUAL CLEARING FROM NW TO SE THIS AFTERNOON BUT WITH
A GUSTY NW WIND AS THE PRESSURE GRADIENT TIGHTENS BEHIND THE
EXITING LOW AND HIGH PRESSURE TO THE WEST. THINK SHOULD STAY BELOW
ADVISORY LEVELS GIVEN A MARGINAL 85H JET BUT APPEARS MIXING WILL
BE GREAT ENOUGH TO PUSH SOME GUSTS TO 35-40 MPH. FOLLOWED CLOSER
TO THE COOLER MAV MOS WEST TODAY WHERE COOL ADVECTION SHOULD KEEP
READINGS FROM RISING TOO MUCH...WHILE STILL MILD EAST WITH AT
LEAST LOW/MID 60S LIKELY GIVEN DOWNSLOPE.
UPPER TROF LIFTS OUT TONIGHT WITH SHORTWAVE RIDGING SLIDING EAST
ACCOMPANIED BY STRONG SURFACE HIGH PRESSURE BUILDING IN FROM THE NW
LATE. DECENT DRYING SHOULD LEAD TO MAINLY CLEAR SKIES UNDER
DIMINISHING WINDS OVERNIGHT WITH GOOD RAD COOLING BY DAYBREAK. THIS
SHOULD ALLOW TEMPS TO FALL BACK TO BELOW FREEZING VALLEYS WHERE
COULD SOME FOG OTRW LOW/MID 30S FOR THE MOST PART.
&&
.SHORT TERM /7 PM THIS EVENING THROUGH SUNDAY NIGHT/...
AS OF 330 AM EST THURSDAY...
FRIDAY WILL START OFF WITH OUR AREA UNDER THE INFLUENCE OF A RIDGE
OF HIGH PRESSURE EXTENDING FROM THE WESTERN GREAT LAKES THROUGH THE
EASTERN FACE OF THE APPALACHIANS. WILL EXPECT ABUNDANT SUNSHINE
UNDER MOSTLY CLEAR SKIES...AND FRIDAY AFTERNOON TEMPERATURES WILL
REMAIN ON THE MILD SIDE...DESPITE BEING COOLER THAN THURSDAYS HIGHS.
EXPECT FRIDAY AFTERNOON HIGHS TO BE IN THE MID TO UPPER 50S
AREAWIDE. CLOUD COVER WILL INCREASE FROM THE SOUTHWEST DURING THE
EVENING AS ANOTHER LOW PRESSURE SYSTEM MOVES OUT OF THE CENTRAL
PLAINS...WITH A TROUGH DEVELOPING FROM THE LOW...AND EXTENDING
THROUGH KENTUCKY INTO WESTERN VIRGINIA BY SATURDAY MORNING.
DRIZZLE AND PERIODS OF RAIN WILL DEVELOP ACROSS THE MOUNTAINS
SATURDAY MORNING AND AFTERNOON AS SOUTHEASTERLY WINDS PUSH ATLANTIC
MOISTURE UP THE BLUE RIDGE. RAIN WILL CONTINUE TO SPREAD EAST
THROUGH THE DAY AS THE LOW PRESSURE SYSTEM MOVES OUT OF THE
PLAINS...AND PUSHES ACROSS KENTUCKY AND TENNESSEE...WHILE A WARM
FRONT WILL PASS THROUGH OUR AREA FROM THE SOUTHWEST DURING THE
EVENING. DESPITE THE ABUNDANT CLOUD COVER AND PERIODS OF RAIN
KEEPING A LID ON DAYTIME HEATING...TEMPERATURES WILL STILL REMAIN ON
THE MILD SIDE...WITH UPPER 40S AND LOW 50S EXPECTED WEST OF THE BLUE
RIDGE...AND MID 50S TO BE FOUND FURTHER EAST.
ON SUNDAY MORNING...A COLD FRONT WILL PUSH THROUGH OUR REGION...AND
WILL EXIT OUR AREA TO THE SOUTH DURING THE AFTERNOON. SHOWER
ACTIVITY WILL DIMINISH ACROSS THE PIEDMONT REGION DURING THE
AFTERNOON AS THE COLD CONTINUES TO SINK SOUTHWARD...AND HIGH
PRESSURE PUSHES IN FROM THE GREAT LAKES REGION...BUILDING SOUTHWARD
ALONG THE EASTERN FACE OF THE APPALACHIANS. HOWEVER...WILL STILL SEE
SPOTTY SHOWER ACTIVITY ACROSS THE NORTH CAROLINA MOUNTAINS INTO
SUNDAY NIGHT AS THE FRONT REMAINS ANCHORED ALONG THE SOUTHERN
APPALACHIANS.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
AS OF 330 AM EST THURSDAY...
CONSIDERABLE DIFFERENCES STILL EXIST AMONG THE VARIOUS GUIDANCE
REGARDING THE TIMING AND COVERAGE OR PRECIPITATION ASSOCIATED WITH
THE SYSTEM PASSING THROUGH THE AREA THIS WEEKEND. WILL CONTINUE TO
FAVOR THE GUIDANCE PUT FORTH BY HPC...WHICH LEANS MORE HEAVILY ON
THE ECMWF ENSEMBLE MEAN.
FOR MONDAY...EXPECT ANOTHER ROUND OF SHOWER ACTIVITY...ESPECIALLY
ACROSS EASTERN AND SOUTHERN SECTIONS OF THE REGION...AS A WAVE
DEVELOPS ALONG THE COLD FRONT SITUATED JUST TO THE SOUTH OF OUR
AREA. SHOWER ACTIVITY WILL DIMINISH MONDAY NIGHT AS THE WAVE PUSHES
OFFSHORE AND THE COLD FRONT MOVES FURTHER SOUTH. THE REGION
TRANSITIONS TO A PROLONGED PERIOD OF NORTHWEST FLOW BEHIND FRONT
INTO EARLY NEXT WEEK. MOISTURE WILL BE LIMITED BEHIND THE FRONT. A
REINFORCING SHOT OF COLD AIR ENTERS THE REGION TUESDAY INTO TUESDAY
NIGHT AS A SECOND COLD FRONT MOVES THROUGH THE REGION. ANTICIPATE
ONLY ISOLATED RAIN OR SNOW SHOWERS ACROSS SE WV WITH ITS
PASSAGE...WITH DRY WEATHER ELSEWHERE. THE EASTERN EXTENT OF AN AREA
OF HIGH PRESSURE ARRIVES ON WEDNESDAY ALONG WITH A TREND TOWARD
COLDER TEMPERATURES.
&&
.AVIATION /17Z THURSDAY THROUGH MONDAY/...
AS OF 1215 PM EST THURSDAY...
DECENT DOWNSLOPING WIND FROM DIRECTION NORMAL TO THE RIDGE
LINE...IN CONJUNCTION WITH VERY DRY AIR...IS RAPIDLY THINNING MUCH
OF THE THICK LLVL MOISTURE WHICH WAS AROUND THIS MORNING. QUITE
IMPRESSIVE FOR A WEAK EARLY FEB SUN ANGLE. THIN BANDS OF BKN CIGS
SHOULD DIMINISH TO NEARLY CLR SKIES OVER THE NEXT FEW HOURS. WINDS
WILL BE GUSTY FROM THE NW AT 15-30 KNOTS THEN DIMINISHING THIS
EVENING AND BECOMING NEAR CALM OVERNIGHT. THIS IN COMBO WITH THE
WET GROUND MAY ALLOW FOR AREAS OF MVFR IN FOG CLOSER TO THE RIVER
BOTTOMS AROUND KLWB AND PERHAPS KBCB LATE.
OTRW LOOKS LIKE A RETURN TO VFR ON FRIDAY AS HIGH PRESSURE BUILDS
IN FROM THE NORTH. HOWEVER MOISTURE WILL ATTEMPT TO MAKE A RETURN
LATER FRIDAY NIGHT ESPECIALLY ACROSS WESTERN SITES.
EXTENDED OUTLOOK PERIOD REMAINS LOW CONFIDENCE AT THIS POINT
PENDING HOW FAR NORTH/EAST MOISTURE WITH THE NEXT SYSTEM MAKES IT
AND EXACTLY WHEN. COULD SEE SOME LOWER CIGS AND LIGHT RAIN ARRIVE
AS EARLY AS SATURDAY...BUT APPEARS MOST LIKELY SAT NIGHT INTO
SUNDAY AS LOW PRESSURE STALLS TO THE WEST AND THEN SHEARS MOISTURE
UNDERNEATH HIGH PRESSURE TO THE NORTH AS EASTERLY UPSLOPE FLOW
DEVELOPS. THIS SCENARIO WITH AT LEAST MVFR CIGS AND RAIN COULD
LAST INTO EARLY NEXT WEEK AS ANOTHER WAVE MOVES UP FROM THE GULF
STATES BUT VERY IFFY AT THIS POINT.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...JH/KM
NEAR TERM...JH/KM
SHORT TERM...NF
LONG TERM...DS/NF
AVIATION...JH/KM
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
341 PM CST THU FEB 2 2012
.SHORT TERM...TONIGHT THROUGH SATURDAY NIGHT
340 PM CST THU FEB 2 2012
AT 3 PM...THE WESTERN EXTENT OF THE LOW CLOUDS REMAINED EAST OF A
LINE FROM THE TWIN CITIES TO SAVANNA ILLINOIS /KSFY/. THE
COMBINATION OF SOUTHEAST WINDS JUST OFF THE SURFACE AND HIGH DEW
POINTS FOR THIS TIME OF YEAR...EXPECT THAT THE WESTERN EDGE OF
THIS CLOUD LINE WILL QUICKLY MOVE WEST EARLY THIS EVENING AND
QUICKLY LOWER. IN ADDITION...THE VISIBILITIES WILL QUICKLY FALL
AS THE TEMPERATURES RAPIDLY APPROACHES THE DEW POINTS THIS
EVENING. THIS WILL RESULT IN THE REDEVELOPMENT OF DENSE FOG ACROSS
THE AREA. THIS FOG WILL INITIALLY BECOME DENSE ON THE RIDGE TOPS
OF WESTERN WISCONSIN...SOUTHEAST MINNESOTA...AND NORTHEAST IOWA
EARLY THIS EVENING...AND THEN SETTLE INTO THE RIVER VALLEYS OF
WESTERN WISCONSIN DURING THE LATE EVENING AND OVERNIGHT. DUE TO
THIS...DECIDED TO GO WITH A DENSE FOG ADVISORY FOR TONIGHT AND
FRIDAY MORNING. WITH BOTH CLIMATOLOGY AND THE FOG TRENDS OVER THE
PAST TWO DAYS...DECIDED THAT NOON WOULD BE THE BEST ENDING TIME
FOR THE DENSE FOG ADVISORY.
WITH THE DEW POINTS AROUND 30...TEMPERATURES WILL HAVE A VERY HARD
TIME APPROACHING THE MOS TEMPERATURE GUIDANCE. AS A RESULT...
RAISED THE MINIMUM TEMPERATURES BY ONE CATEGORY.
FROM FRIDAY THROUGH SATURDAY NIGHT...THE 02.12Z MODELS CONTINUED A
TREND OF THE 01.18Z AND 02.00Z SHOWED AND IT SHIFTED THE LOW
PRESSURE SYSTEM A BIT FURTHER SOUTH AS A REX BLOCK DEVELOPS ACROSS
THE CANADIAN PRAIRIES AND CENTRAL PLAINS. THE HIGH ASSOCIATED WITH
THIS BLOCK WILL FORCE THE LOW PRESSURE SYSTEM FURTHER SOUTH...AND
AS RESULT THE PRECIPITATION REMAINS FROM SOUTHERN IOWA SOUTH TO
THE WESTERN GULF OF MEXICO. WITH THIS TREND BEING CONSISTENT...THE
PRECIPITATION CHANCES FOR THIS TIME PERIOD WAS REMOVED FROM THE
FORECAST.
.LONG TERM...SUNDAY THROUGH THURSDAY
340 PM CST THU FEB 2 2012
FROM SUNDAY THROUGH TUESDAY NIGHT...A PACIFIC HIGH PRESSURE SYSTEM
WILL REMAIN IN CONTROL OF THE WEATHER ACROSS THE AREA. THIS HIGH
WILL PROVIDE DRY WEATHER FOR THIS TIME PERIOD. WITH THE MOS
TEMPERATURE GUIDANCE BIAS BEING TOO COOL AND LOSS OF THE DEEPER
SNOW PACK...TEMPERATURES WERE ADJUSTED UPWARD BY ABOUT 3 DEGREES.
BEYOND THIS TIME PERIOD...THE MODELS CONTINUE TO STRUGGLE AS A
MODERATE TO STRONG NEGATIVE ARCTIC OSCILLATION DEVELOPS. THIS
WILL RESULT IN THE DEVELOPMENT OF AN AMPLIFIED TROUGH ACROSS
EASTERN CANADA...GREAT LAKES...AND NEW ENGLAND. THE MODELS
CONTINUE TO SHOW THAT THE ARCTIC AIR ASSOCIATED WITH THIS LONG
WAVE TROUGH WILL EITHER JUST BRIEFLY MOVE THROUGH THE AREA OR
REMAIN TO OUR EAST. THIS ACTUALLY FITS IN WELL WITH A COMPOSITE
ANALYSIS WHICH SHOWS NO STRONG STATISTICAL SIGNAL BETWEEN THE
PHASE OF THE ARCTIC OSCILLATION AND THE AVERAGE FEBRUARY
TEMPERATURES FOR OUR AREA OF THE COUNTRY. THE WESTERN EXTENT OF
THIS TROUGH WILL BE GREATLY AFFECTED BY THE TELECONNECTION WITH THE
ANOMALOUS THUNDERSTORM ACTIVITY THAT IS CONTINUING TO OCCUR ACROSS
INDONESIA AND THE WESTERN PACIFIC. SINCE THIS CONVECTION IS VERY
SIMILAR TO WHAT WOULD BE SEEN IN PHASE 5. DURING THIS PHASE...LONG
WAVE TROUGHS TYPICALLY HAVE A HARD TIME MAINTAINING THEMSELVES
ACROSS THE MID AND UPPER MISSISSIPPI RIVER VALLEY. THIS IS IN
VERY GOOD AGREEMENT WITH THE CFS VERSION 2 WHICH HAS BEEN SHOWING
THIS SCENARIO CONSISTENTLY FOR THE PAST TWO WEEKS. FOR THE TIME
BEING...JUST COOLED THE TEMPERATURES TO EITHER SLIGHTLY BELOW OR
NEAR NORMAL FROM WEDNESDAY THROUGH THURSDAY.
&&
.AVIATION...THROUGH 18Z FRIDAY
1157 AM CST THU FEB 2 2012
MAIN AVIATION FORECAST CONCERN IS THE WESTWARD PROGRESSION OF LOW
STRATUS/FOG DECK ACROSS EASTERN MINNESOTA...NORTHEAST IOWA AND
MUCH OF WISCONSIN. LATEST VISIBLE SATELLITE IMAGERY SHOWING BACK
EDGE OF STRATUS DECK EXTENDED JUST EAST-NORTHEAST OF RST TAF SITE
TO NEAR CHARLES CITY IOWA. LATEST 17Z METARS INDICATING CEILING
HEIGHTS IN THE LIFR AND IFR RANGE ACROSS MUCH OF THE AREA. WITH
ABUNDANT LOW LEVEL MOISTURE...WEAK WINDS IN THE NEAR SURFACE
BOUNDARY LAYER AND STRONG INVERSION IN PLACE OVER REGION. EXPECT
IFR TO LIFR CONDITIONS TO CONTINUE THROUGH TAF PERIOD AT LSE. BIG
QUESTION WILL BE STRATUS/FOG DECK MOVING BACK WESTWARD INTO RST
TAF SITE LATE THIS AFTERNOON AND EVENING. LATEST 02.15Z RUC 975MB
RELATIVE HUMIDITY IS CURRENTLY HANDLING STRATUS DECK WELL PER
LATEST VISIBLE AND SHOWS THIS MOISTURE ADVECTING BACK WESTWARD
INTO RST BY 00Z FRIDAY. LATEST VISIBLE SATELLITE LOOP SHOWS A VERY
SLOW PROGRESSION WESTWARD. WITH THIS...HAVE INTRODUCED LIFR/IFR
CONDITIONS AT RST TAF SITE BY 01Z FRIDAY AND CONTINUED THROUGH THE
REST OF THE TAF PERIOD.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
248 PM CST THU FEB 2 2012
WI...DENSE FOG ADVISORY UNTIL NOON CST FRIDAY FOR WIZ041>044-053>055-
061.
DENSE FOG ADVISORY FROM 6 PM THIS EVENING TO NOON CST FRIDAY FOR
WIZ017-029-032>034.
MN...DENSE FOG ADVISORY UNTIL NOON CST FRIDAY FOR MNZ096.
DENSE FOG ADVISORY FROM 6 PM THIS EVENING TO NOON CST FRIDAY FOR
MNZ079-086>088-094-095.
IA...DENSE FOG ADVISORY UNTIL NOON CST FRIDAY FOR IAZ009>011-019-029-
030.
DENSE FOG ADVISORY FROM 6 PM THIS EVENING TO NOON CST FRIDAY FOR
IAZ008-018.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...DTJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1157 AM CST THU FEB 2 2012
.SHORT TERM...
1022 AM CST THU FEB 2 2012
WITH ABUNDANT LOW LEVEL MOISTURE AND STRONG INVERSION OVER PARTS
OF NORTHEAST IOWA AND SOUTHWEST WISCONSIN...VISIBILITIES CONTINUE
TO BE A QUARTER OF A MILE OR LESS PER LATEST 16Z METARS.
THEREFORE...HAVE EXTENDED THE DENSE FOG ADVISORY TO 20Z THURSDAY OVER
THIS AREA. DENSE FOG HAS BEGUN TO BURN OFF OVER PORTIONS OF
SOUTHEAST MINNESOTA AND NORTHEAST IOWA...AND VISIBILITIES HAVE
IMPROVED OVER PORTIONS OF WESTERN AND CENTRAL WISCONSIN. HAVE
ALLOWED THE DENSE FOG ADVISORY TO EXPIRE OVER THIS AREA.
.LONG TERM...SUNDAY THROUGH WEDNESDAY
330 AM CST THU FEB 2 2012
PLENTY OF DETAIL DIFFERENCES FOR THE DAY 4-7 PORTION OF THE FCST BUT
THE VAST PORTION OF IT LOOKS TO BE DOMINATED BY A DRY WEST-NORTHWEST
FLOW AS THE 500MB RIDGE AXIS FLATTENS SUN THEN REBUILDS OVER
WESTERN NOAM MON INTO WED. DETAIL DIFFERENCES ARE CENTERED ON
VARIOUS DIFFICULT TO TIME SHORTWAVES IN THE WEST-NORTHWEST FLOW
ALOFT. SFC HIGH PRESSURE WITH THE DECAYING REX-BLOCK PORTION OF
THE FLOW ALOFT SETTLES OVER THE AREA FOR SUN. STRONGER NORTHWEST
FLOW ALOFT LOOKS TO BECOME ESTABLISHED OVER THE AREA FOR MON-WED.
APPEARS ONE SHORTWAVE TROUGH TO SLIDE SOUTHEAST ACROSS THE AREA MON
AND ANOTHER WED. MOISTURE WITH WEST/NORTHWEST FLOW SYSTEMS IN THE
DAY 4-7 TIME-FRAME ALWAYS A QUESTION. FAVORING THE MODEL/ENSEMBLE
CONSENSUS...LEFT MON-WED DRY FOR NOW. WITH THE WEST-NORTHWEST FLOW
ALOFT TEMPS FOR SUN-WED TRENDING TO REMAIN ABOVE NORMAL WITH THE
ARCTIC AIR LOCKED UP IN CENTRAL/NORTHERN CAN.
&&
.AVIATION...THROUGH 18Z FRIDAY
1157 AM CST THU FEB 2 2012
MAIN AVIATION FORECAST CONCERN IS THE WESTWARD PROGRESSION OF LOW
STRATUS/FOG DECK ACROSS EASTERN MINNESOTA...NORTHEAST IOWA AND
MUCH OF WISCONSIN. LATEST VISIBLE SATELLITE IMAGERY SHOWING BACK
EDGE OF STRATUS DECK EXTENDED JUST EAST-NORTHEAST OF RST TAF SITE
TO NEAR CHARLES CITY IOWA. LATEST 17Z METARS INDICATING CEILING
HEIGHTS IN THE LIFR AND IFR RANGE ACROSS MUCH OF THE AREA. WITH
ABUNDANT LOW LEVEL MOISTURE...WEAK WINDS IN THE NEAR SURFACE
BOUNDARY LAYER AND STRONG INVERSION IN PLACE OVER REGION. EXPECT
IFR TO LIFR CONDITIONS TO CONTINUE THROUGH TAF PERIOD AT LSE. BIG
QUESTION WILL BE STRATUS/FOG DECK MOVING BACK WESTWARD INTO RST
TAF SITE LATE THIS AFTERNOON AND EVENING. LATEST 02.15Z RUC 975MB
RELATIVE HUMIDITY IS CURRENTLY HANDLING STRATUS DECK WELL PER
LATEST VISIBLE AND SHOWS THIS MOISTURE ADVECTING BACK WESTWARD
INTO RST BY 00Z FRIDAY. LATEST VISIBLE SATELLITE LOOP SHOWS A VERY
SLOW PROGRESSION WESTWARD. WITH THIS...HAVE INTRODUCED LIFR/IFR
CONDITIONS AT RST TAF SITE BY 01Z FRIDAY AND CONTINUED THROUGH THE
REST OF THE TAF PERIOD.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
1022 AM CST THU FEB 2 2012
WI...DENSE FOG ADVISORY UNTIL 2 PM CST THIS AFTERNOON FOR WIZ041>044-
053>055-061.
MN...DENSE FOG ADVISORY UNTIL 2 PM CST THIS AFTERNOON FOR MNZ096.
IA...DENSE FOG ADVISORY UNTIL 2 PM CST THIS AFTERNOON FOR IAZ009>011-
019-029-030.
&&
$$
SHORT TERM...DTJ
LONG TERM....RRS
AVIATION...DTJ
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
325 PM MST THU FEB 2 2012
.SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT
HAZARDOUS WINTER STORM CONTINUES TO LOOK ON TRACK TO ARRIVE THIS
EVENING ACROSS SOUTHEAST WYOMING AND THE WESTERN NEBRASKA
PANHANDLE. 500MB RUC ANALYSIS AT 20Z SHOWS THE MIDLEVEL TROUGH
CLOSING OFF TO THE EAST OF THE FOUR CORNERS REGION. UPPER LEVEL
DIVERGENCE TO THE NORTHEAST OF THE LOW IS CURRENTLY PRODUCING AN
AREA OF IR ENHANCEMENT STRETCHING FROM DENVER TO GOODLAND. THE
MODELS AGREE IN INCREASING LLVL N-NE UPSLOPE WINDS THRU THE EVENING
AND MOISTENING THE LOW/MID LEVELS. WHILE THE CURRENT DEWPOINT
DEPRESSIONS ARE HIGH TO THE EAST OF THE LARAMIE RANGE (15-20F)...LOW
LEVEL COLD-AIR ADVECTION AND TOP-DOWN MOISTENING WILL RESULT IN
SATURATION BY THIS EVENING. LOOKS LIKE THE PERIOD FROM 00Z-06Z IN
PARTICULAR IS FAVORABLE FOR HIGH SNOWFALL RATES ACROSS SOUTHEAST WY.
A BUFKIT TIME-HEIGHT PLOT FROM KCYS SHOWS THE COMBINATION OF
EASTERLY 700MB WINDS AND UPWARD MOTION IN THE DENDRITE GROWTH ZONE
BEING MAXIMIZED BETWEEN 00Z-06Z. SNOWFALL ACROSS THE NE PANHANDLE
WILL LIKELY HOLD OFF UNTIL LATE TONIGHT WHEN THE MIDLEVEL DYNAMICS
ARRIVE.
THE 500MB LOW WILL BEGIN ITS PROGRESSION TO THE NORTHEAST ON
FRIDAY MOVING...MOVING ACROSS EASTERN CO AND NORTHWESTERN KS. THE
HEAVIEST SNOWFALL ON FRIDAY...ESPECIALLY BY AFTN...IS EXPECTED OVER
THE SOUTHERN PART OF THE NEBRASKA PANHANDLE CLOSEST TO THE 700MB
LOW. 700MB FCTS AT 18Z FRI SHOW AN AXIS OF HIGHER NE WINDS (AROUND
35 KTS) STRETCHING ACROSS CHEYENNE COUNTY. BUFKIT SOUNDINGS AT KSNY
AT 18Z SUPPORT GUSTS TO 35 KTS...THUS WILL CONTINUE THE BLIZZARD
WARNING ACROSS CHEYENNE COUNTY. ANY SUBSTANTIAL MIDLEVEL
FRONTOGENESIS IS PROGGED TO BE SOUTH AND EAST OF THE CWA THROUGHOUT
THE ENTIRE EVENT. THUS...NOT EXPECTING OVERLY HIGH SNOWFALL
RATES...HOWEVER THE LONG DURATION OF LOW-LEVEL UPSLOPE WILL PRODUCE
STORM TOTAL SNOWFALL AMOUNTS BETWEEN 7 TO 10 INCHES ALONG INTERSTATE
80 THROUGH FRIDAY NIGHT. EXPECT HIGHER AMOUNTS IN THE
OROGRAPHICALLY FAVORED SOUTH LARAMIE RANGE NEAR THE I-80 SUMMIT.
AMOUNTS WILL DROP OFF TO THE NORTH AND WEST...IN AREAS FURTHER
REMOVED FROM THE MIDLEVEL LOW. SNOW WILL BEGIN TO TAPER OFF FROM
WEST TO EAST OVER THE CWA BY LATE FRIDAY NIGHT AS THE MAIN 500MB LOW
CONTINUES ITS PROGRESSION EASTWARD AND THE SFC HIGH SETTLES OVER
SOUTHEAST WY.
.LONG TERM...SATURDAY THROUGH THURSDAY
12Z GFS AND ECMWF 500 MB SYNOPTIC PATTERNS SIMILAR...LEADING TO
MODERATE TO HIGH CONFIDENCE IN THEIR RESPECTIVE MODEL SOLUTIONS.
SATURDAY...SHORTWAVE TROUGH ALOFT WILL BE MOVING OFF TO OUR
EAST...THUS DECREASING SNOW CHANCES ACROSS OUR SOUTHERN COUNTIES.
SUNDAY...SLOW WARMING TREND ON TAP AS HEIGHTS AND THICKNESSES RISE.
DRY WITH LACK OF LOW AND MID LEVEL MOISTURE.
MONDAY...ANOTHER WEAK COLD FRONT MOVES SOUTH ACROSS OUR
COUNTIES...THOUGH THE BULK OF THE COLDER AIR WILL REMAIN NORTH AND
EAST OF OUR AREA. CONTINUED DRY WITH LIMITED LOW AND MID LEVEL
MOISTURE.
TUESDAY-THURSDAY...DRY NORTHWEST FLOW ALOFT WILL PREVAIL. WARMING
TREND WILL CONTINUE AS HEIGHTS AND THICKNESSES RISE.
&&
.AVIATION...18Z TAFS
THROUGH 00Z...CIGS AND VISIBILITIES LOWERING
TO IFR IN SNOW AND FOG ACROSS CARBON COUNTY WITH MOUNTAIN
OBSCURATION. VFR ELSEWHERE.
AFTER 00Z...WIDESPREAD IFR AND LIFR DEVELOPING IN SNOW AND FOG
AT RAWLINS...LARAMIE...CHEYENNE AND SIDNEY ALONG WITH MOUNTAIN
OBSCURATION. MVFR DUE TO CLOUDS...SNOW AND FOG DEVELOPING AT
CHADRON...SCOTTSBLUFF AND ALLIANCE.
AFTER 12Z...WIDESPREAD IFR IN SNOW AND FOG...WITH LIFR AND VLIFR AT
TIMES AT LARAMIE...CHEYENNE AND SIDNEY. MOUNTAINS OBSCURED. RUBIN
&&
.FIRE WEATHER...NO FIRE WEATHER CONCERNS
&&
.CYS WATCHES/WARNINGS/ADVISORIES...
WY...WINTER STORM WARNING UNTIL 11 PM FRIDAY FOR WYZ106-WYZ107-WYZ116-
WYZ117-WYZ118-WYZ119.
WINTER WEATHER ADVISORY UNTIL 5 PM FRIDAY FOR WYZ103-WYZ114-
WYZ115.
WINTER WEATHER ADVISORY FROM 11 PM THURSDAY TO 11 PM FRIDAY FOR
WYZ108.
NE...WINTER WEATHER ADVISORY FROM 11 PM THURSDAY TO 11 PM FRIDAY FOR
NEZ003-NEZ019-NEZ096.
WINTER STORM WARNING FROM 11 PM THURSDAY TO 11 PM FRIDAY FOR
NEZ020-NEZ021-NEZ054.
BLIZZARD WARNING FROM 11 PM THURSDAY TO 11 PM FRIDAY FOR NEZ055.
&&
$$
SHORT TERM/FIRE WEATHER...FINCH
LONG TERM/AVIATION...RUBIN