Forecast Discussions mentioning any of
"HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 11/13/12
AREA FORECAST DISCUSSION
NWS GRAND JUNCTION CO
1133 AM MST SUN NOV 11 2012
.UPDATE
ISSUED AT 1133 AM MST SUN NOV 11 2012
WEBCAMS ACROSS THE AREA SHOW SNOW CONTINUING OVER TELLURIDE AND
VAIL PASS. LATEST HRRR MODEL DATA ALSO INDICATES MORE BANDS SETTING
UP THIS AFTERNOON AIDED BY FAVORABLE OROGRAPHICS. VISIBLE SATELLITE
IMAGERY CORROBORATES THIS WITH SOME ENHANCED TOPS SHOWING UP OVER
THE MOUNTAINS IN COLORADO. AS SUCH...WILL KEEP WARNINGS AND
ADVISORIES IN PLACE WITH ANOTHER 2 TO 4 INCHES OF NEW SNOW
POSSIBLE THROUGH THIS EVENING. FORECAST LOOKS GOOD ASIDE FROM SOME
MINOR TWEAKS TO SKY GRID.
&&
.SHORT TERM...(TODAY THROUGH MONDAY)
ISSUED AT 322 AM MST SUN NOV 11 2012
THE SYNOPTIC PICTURE IS SIMPLE WHILE THE DETAILS REMAIN COMPLEX.
THE SECOND FRIGID COLD FRONT WORKED THROUGH THE REGION OVERNIGHT
BRINGING WIDESPREAD SNOWFALL MAINLY TO THE CENTRAL ZONES. IN NW
FLOW 700 MB TEMPERATURES DROP TO -16C BY MIDDAY SO ANY AVAILABLE
MOISTURE THAT ENCOUNTERS ANY LIFT AT ALL WILL EFFICIENTLY PRODUCE
BIG FLUFFY DENDRITIC SNOW CRYSTALS. IN ADDITION THE MODELS SHOW A
DEFORMATION ZONE PASSING THROUGH NW-WEST CENTRAL COLORADO THIS
MORNING INTO EARLY AFTERNOON. SO MICROPHYSICS...OROGRAPHICS...AND
SOME DYNAMICS ALL COMBINE TO STACK UP SNOWFALL TODAY OVER THE
CENTRAL AND NORTHERN CO MTNS AND ADJOINING VALLEYS.
IN THE NW SAN JUAN MTNS THIS EARLY MORNING...RADAR VAD WINDS
INDICATED NORTH AT 15KTS AT 11KFT AND MONTROSE AND TELLURIDE HAVE
BEEN SNOWING FOR SEVERAL HOURS THIS EARLY MORNING. MONTROSE MAY
REACH SNOW ADVISORY CRITERIA AND THE UNCOMPAHGRE GORGE COULD BE
GETTING LARGE ACCUMULATIONS THIS EARLY MORNING. SO EXTENDED THE
WARNING FOR ZONE 18 UNTIL 6 PM WITH HIGHWAY 550 AND 145 TRAVEL
EXPECTED TO BE IMPACTED.
SNOTEL SITES INDICATE STORM TOTALS OF TWO FEET ON THE FLATTOPS AND
GRAND MESA AND OVER SCHOFIELD PASS IN THE WEST ELKS. TOWER SITE IN
THE PARK RANGE HAS APPROACHED A FOOT NEW THIS EARLY MORNING SO WE
UPGRADED THE ADVISORY FOR ZONE 4 TO WARNING. WITH THE WEAK
DISTURBANCE PASSING TO THE EAST THIS AFTERNOON AND WARM ADVECTION
BEGINNING ALOFT...ALL SNOW HIGHLIGHTS END AT 6 PM.
SUNDAY NIGHT WILL BE FRIGID WITH NEW RECORD LOWS POSSIBLE AT ALL
LOCATIONS. ICE FOG IS POSSIBLE OVERNIGHT MAINLY IN THE VALLEY
BOTTOMS AND NORTH SLOPES OF MOUNTAINS. AS WARM AIR POURS IN
ALOFT... FORECAST SOUNDINGS SHOW A NEAR ISOTHERMAL LAYER FROM THE
SURFACE UP TO 650MB OR 12KFT ELEVATION. THUS EXPOSED HIGH MTN
SLOPES EVEN NEAR TIMBERLINE MAY NOT BE AS COLD AS THE VALLEY
BOTTOMS.
MONDAY THE VALLEYS WILL REMAIN STRONGLY CAPPED WHILE THE SLOPES
SHOW A WARMING TREND. HIGH CLOUDS INVADE ESPECIALLY ACROSS THE
NORTHERN ZONES AHEAD OF A WEAK ZONAL DISTURBANCE.
.LONG TERM...(MONDAY NIGHT THROUGH SATURDAY)
ISSUED AT 322 AM MST SUN NOV 11 2012
A WEAK WAVE PASSES MONDAY NIGHT AND CLIPS THE NORTHERN ZONES
TRIGGERING A FEW LIGHT SNOW SHOWERS. OTHERWISE LITTLE IMPACT
EXPECTED FROM THIS SYSTEM OUTSIDE OF AN INCREASE IN CLOUD COVER
INTO TUESDAY MORNING. THIS SHOULD HELP TO MODERATE LOWS A BIT OVER
THE POTENTIAL RECORD COLD EXPECTED MONDAY MORNING.
AS THIS SYSTEM EXITS TUESDAY MORNING...SHRTWV RIDING WILL BUILD IN
AND BRING CLEAR/DRY CONDITIONS THROUGH THURSDAY. VALLEY INVERSIONS
WILL BE SLOW TO BREAK...SO WILL BE SHAVING A FEW DEGREES OF MAX
TEMPS UNTIL FLOW ALOFT SWINGS BACK TO THE SOUTHWEST LATE THURSDAY.
MODELS CONTINUE TO SLOW DOWN AND BACK OFF THE NEXT SYSTEM THAT IS
NOW DELAYED INTO THE FRIDAY/SATURDAY TIME FRAME. APPEARS THAT WE
WILL SEE A SERIES OF WEAK WAVES KICKING OUT OF THE BASE OF THE
TROUGH...WITH EACH SYSTEM LOSING ENERGY AS IT MOVES ACROSS THE
SOUTHWEST U.S. BIGGEST IMPACT AT THIS TIME WILL BE BETTER MIXING
TO ALLOW WARMER AIR ALOFT TO MIX INTO THE VALLEYS AND BRING
LOCALLY BREEZY CONDITIONS TO THE AREA ALONG WITH A FEW MOUNTAIN
SHOWERS. TEMPS WILL BE RETURNING TO MORE SEASONAL NORMS AS THE
WEEK CLOSES...EVEN WITH THE INCREASED CLOUD COVER AND POTENTIAL
FOR SHOWERS IN THE REGION.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z NOON MONDAY)
ISSUED AT 936 AM MST SUN NOV 11 2012
OFF AND ON SNOW AND LOW CLOUDS ARE EXPECTED FOR KASE KEGE AND KSBS
WITH MVFR TO IFR CIGS AND VIS THROUGH THE EARLY AFTERNOON HOURS.
SOME CLEARING IS EXPECTED AFTER THAT WITH POSSIBLY A RETURN TO
SOME SNOWSHOWERS IN THE EARLY EVENING HOURS.
SOME FOG WAS REPORTED EARLIER THIS MORNING BUT HAS BURNED OFF WITH
REMAINING TAF SITES EXPECTED TO REMAIN VFR WITH SOME MID TO HIGH
CLOUDS HANGING AROUND.
SOME MORNING FOG WILL BE POSSIBLE FOR MANY VALLEY LOCATIONS
TOMORROW MORNING WITH VIS DROPPING TO LESS THAN A MILE AT TIMES.
THE FOG SHOULD DISSIPATE BETWEEN 0900 AND 1000.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...WINTER STORM WARNING UNTIL 6 PM MST THIS EVENING FOR COZ004-009-
013-018.
WINTER WEATHER ADVISORY UNTIL 6 PM MST THIS EVENING FOR COZ003-
005-008-010.
UT...NONE.
&&
$$
UPDATE...TGR
SHORT TERM...JOE
LONG TERM...JDC
AVIATION...TGR
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
405 AM EST SUN NOV 11 2012
.SYNOPSIS...
08Z WATER VAPOR AND H4 RAP ANALYSIS SHOW A HIGHLY AMPLIFIED UPPER
LEVEL PATTERN IN PLACE OVER THE CONUS EARLY THIS MORNING. PATTERN IS
DOMINATED BY AN IMPRESSIVE TROUGH OVER THE INTER-MOUNTAIN
WEST/PLAINS/UPPER MIDWEST. AS A RESULT OF THE IMPRESSIVE HEIGHT
FALLS TO OUR WEST...WE ARE SEEING AN OVERALL AMPLIFICATION TO THE
UPPER RIDGE WHICH NOW COVERS THE GULF OF MEXICO AND SOUTHEAST
PORTION OF THE CONUS. THIS RIDGE WILL HELP KEEP OUR LOCAL WEATHER
GENERALLY DRY AND WARM THE NEXT COUPLE OF DAYS.
AT THE SURFACE...1030+MB HIGH OFF THE MID-ATLANTIC COAST RIDGES ALL
THE WAY DOWN THE EASTERN SEABOARD TO THE GULF OF MEXICO. THIS
POSITIONS IS SUPPLYING OUR REGION WITH A FAIRLY TIGHT PRESSURE
GRADIENT AND RESULTING EASTERLY FLOW. A FEW LOW LEVEL CLOUDS
ASSOCIATED WITH ATLANTIC MOISTURE HAVE BEEN TRAVERSING THE PENINSULA
THIS MORNING WITHIN THE LOW LEVEL FLOW...AND THIS PATTERN WILL
PROVIDE A MIX OF SUN AND CLOUDS FOR TODAYS FORECAST. EARLY MORNING
TEMPERATURES ARE SEASONABLE WITH MANY LOCATIONS DOWN INTO THE
50S...AND EVEN A FEW UPPER 40S OVER THE NORTHERN NATURE COAST ZONES.
&&
.SHORT TERM (TODAY THROUGH TUESDAY)...
TODAY/TONIGHT...PATTERN WILL BE DOMINATED BY STACKED RIDGING. THE
INFLUENCE/LARGE SCALE SUBSIDENCE ASSOCIATED WITH THE UPPER RIDGE CAN
BE SEEN CLEARLY ON THE 00Z KTBW SOUNDING PROFILE WITH A WELL DEFINED
SUBSIDENCE INVERSION AROUND 800MB. THE FORECAST UNDER THIS
SUPPRESSION WILL BE FAIR AND DRY TODAY. THE TIGHT GRADIENT AND AMPLE
SUNSHINE WILL PROMOTE GOOD DIURNAL MIXING. 850MB TEMPS AROUND 11C
AND MIXING SIMILAR TO WHAT WAS SEEN SATURDAY SHOULD ALLOW MANY
LOCATIONS TO TOP OUT WITHIN A DEGREE OR 2 OF 80 THIS AFTERNOON.
THE SLOW MODERATION TO OVERNIGHT LOWS WILL CONTINUE TONIGHT WITH
TEMPS UP A FEW DEGREES FROM THIS MORNING. LOOKING FOR LOW TEMPS
TO GENERALLY BE IN THE UPPER 50S TO AROUND 60.
MONDAY...UPPER RIDGE WILL STILL BE IN CONTROL THROUGH MUCH OF THE
DAY BUT WILL BEGIN TO DE-AMPLIFY IN RESPONSE TO THE EASTWARD
PROPAGATION OF THE CENTRAL U.S. TROUGH. NWP GUIDANCE IS IN GOOD
AGREEMENT THAT THE MAJORITY OF THE ENERGY ASSOCIATED WITH THIS
TROUGH WILL PASS TO OUR NORTH. SURFACE COLD FRONT WILL BE MOVING
ALONG THE NORTHERN GULF COAST DURING MONDAY...AND ANY ASSOCIATED
SHOWER ACTIVITY WILL REMAIN TO THE NW/W OF OUR FORECAST AREA. LOW
LEVEL MOISTURE RECOVERY MAY BE ENOUGH TO ALLOW A FEW LOW-TOPPED
SPEED CONVERGENCE SHOWERS FROM THE EAST COAST TO BEGIN SURVIVING THE
TREK ACROSS THE STATE. CAN NOT RULE OUT A BRIEF SPRINKLE FOR A FEW
SPOTS ON MONDAY...BUT COVERAGE AND IMPACT WOULD BE VERY LOW. FOR NOW
WILL LEAVE RAIN CHANCES AT A SILENT 10%. TEMPERATURES UNDER THE
UPPER RIDGE WILL AGAIN BE ABOVE NORMAL WITH MANY SPOTS REACHING THE
LOWER 80S.
MONDAY NIGHT/TUESDAY...UPPER TROUGH QUICKLY PIVOTS AWAY FROM THE
REGION WITH LEFTOVER MASS FIELDS NOT PROVIDING MUCH OF A PUSH
SOUTHWARD TO THE COLD FRONT. LOOKS LIKE AN ILL-DEFINED BOUNDARY WILL
PUSH INTO THE REGION EARLY TUESDAY AND THEN WASH-OUT. WILL NOT SEE
MUCH IN THE WAY OF CAA WITH THIS FRONT AND TEMPERATURES WILL STAY AT
OR SLIGHTLY ABOVE NORMAL INTO THE MIDDLE OF THE WEEK. ALSO...NOT
ANTICIPATING MUCH IN THE WAY OF DEEP LAYER SYNOPTIC SUPPORT FROM
THIS TROUGH AND LOW LEVEL FOCUS ASSOCIATED WITH THE FRONT WILL NOT
BE IMPRESSIVE EITHER. WILL GO WITH A SLIGHT CHANCE 20% POP FOR A FEW
ISOLATED SHOWERS...GENERALLY NORTH OF THE I-4 CORRIDOR. AT THIS
TIME...THIS FRONT LOOKS TO BE A RATHER UNEVENTFUL PASSAGE IN TERMS
OF SENSIBLE WEATHER.
&&
.LONG TERM (WEDNESDAY THROUGH NEXT SUNDAY)...
WEAK FRONTAL BOUNDARY WILL HAVE STALLED AND BASICALLY DISSIPATED BY
WEDNESDAY SOMEWHERE IN THE VICINITY OF CENTRAL FLORIDA. THE FRONT
ITSELF WILL HAVE VERY LITTLE IMPACT ON THE REGION...BUT SOME
SLIGHTLY DRIER AIR WILL MOVE IN ALONG WITH A RETURN TO TEMPERATURES
CLOSER TO NORMAL FOR THIS TIME OF YEAR.
MODEL DIFFERENCES LEAD TO SOME UNCERTAINTY IN THE FORECAST FOR THE
END OF THE WEEK. A SHORT-WAVE TROUGH WILL BE MOVING EASTWARD ACROSS
THE SOUTHERN STATES...POSSIBLY AS FAR SOUTH AS THE GULF COAST. THE
GFS...CANADIAN...AND ECMWF ALL SHOW THIS FEATURE...BUT NONE OF THEM
AGREE ON TIMING OR AMPLITUDE. THE 12Z ECMWF HAS A SLOW MOVING CLOSED
MID-LEVEL LOW MOVING ACROSS NORTH FLORIDA. THIS RESULTS IN A CHANCE
FOR SHOWERS ACROSS MUCH OF OUR REGION ON THURSDAY...ESPECIALLY NORTH
OF TAMPA BAY. THE GFS SHOWS A WEAKER TROUGH OVER FLORIDA WITH THE
MAIN ENERGY CONTINUING EASTWARD WELL NORTH OF THE STATE. THE
CANADIAN MODEL HAS A VERY SHARP TROUGH AXIS MOVING ACROSS NORTHERN
ALABAMA AND GEORGIA WEDNESDAY NIGHT...THEN SWINGING RAPIDLY OFF THE
EASTERN SEABOARD BY MID DAY THURSDAY. THE SPEED AND AMPLITUDE OF
THIS FEATURE WILL HAVE AN IMPACT ON THE NEXT UPSTREAM SYSTEM AS
WELL...WHICH POTENTIALLY CROSSES FLORIDA ON SATURDAY AND MAY BE A
CATALYST FOR DEVELOPING LOW PRESSURE IN THE ATLANTIC BEYOND THIS
FORECAST PERIOD. THE BEST COURSE OF ACTION AT THIS TIME WOULD BE TO
USE A BLEND OF GUIDANCE...IN THIS CASE THE GFS AND ECMWF TO
INTRODUCE A SLIGHT CHANCE OF SHOWERS EACH DAY MAINLY NORTH OF TAMPA
BAY AND OVER THE INTERIOR.
&&
.AVIATION...
VFR NEXT 24 HOURS. MAY SEE OCCASIONAL CEILINGS BETWEEN 4000 AND 6000
FEET TODAY. WINDS WILL BECOME GUSTY FROM THE EAST DURING THE
AFTERNOON HOURS.
&&
.MARINE...
A STRONG AREA OF HIGH PRESSURE WILL CONTINUE TO RIDGE DOWN THE
EASTERN SEABOARD TO THE GULF OF MEXICO KEEPING THE LOCAL GRADIENT
TIGHT THROUGH THE DAY. THE INFLUENCE OF THIS RIDGE OF HIGH PRESSURE
WILL WEAKEN BY MONDAY NIGHT AND TUESDAY AS A WEAK COLD FRONT
APPROACHES FROM THE WEST. THIS COLD FRONT WILL DISSIPATE OVER THE
REGION TUESDAY NIGHT AND WEDNESDAY AS HIGH PRESSURE ONCE AGAIN BUILD
TO OUR NORTH.
&&
.FIRE WEATHER...
NO SIGNIFICANT FIRE WEATHER CONCERNS ARE ANTICIPATED THROUGH THE
EARLY PORTION OF THE WEEK. A FEW LOCATIONS WILL SEE RELATIVE
HUMIDITY VALUES DROP INTO THE UPPER 30S THIS AFTERNOON ALONG WITH
BREEZY EASTERLY WINDS. THESE CONDITIONS WILL AID THE SPREAD OF
WILDFIRES...HOWEVER RED FLAG CRITERIA ARE NOT EXPECTED TO BE MET.
&&
.PRELIMINARY POINT TEMPS/POPS...
TPA 82 64 81 64 / 0 0 10 10
FMY 82 63 83 62 / 0 0 10 10
GIF 80 60 82 61 / 10 10 10 10
SRQ 82 62 81 63 / 0 0 10 10
BKV 81 57 82 58 / 0 0 10 10
SPG 79 66 80 67 / 0 0 10 10
&&
.TBW WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
GULF WATERS...NONE.
&&
$$
SYNOPSIS/SHORT TERM/MARINE/FIRE WX...MROCZKA
LONG TERM/AVIATION...JILLSON
AREA FORECAST DISCUSSION
NWS LINCOLN IL
300 PM CST SUN NOV 11 2012
.DISCUSSION...
ISSUED 300 PM CST SUN NOV 11 2012
VIGOROUS SYSTEM APPROACHING CENTRAL AND SOUTHEAST ILLINOIS HAS
RESULTED IN STRONG SOUTHERLY WINDS TODAY...WITH NUMEROUS GUSTS
OVER 40 MPH ACROSS CENTRAL ILLINOIS. A FEW GUSTS OF 50-55 MPH HAVE
BEEN REPORTED AS WELL. COLD FRONT IS ALREADY MAKING STEADY
PROGRESS ACROSS THE FORECAST AREA...CROSSING THE IL RIVER VALLEY
AT THE MOMENT. MAIN FORECAST CONCERN TODAY REVOLVES AROUND
WIND...PRECIPITATION...TEMPERATURES EITHER SIDE OF TONIGHT/S
FROPA. OTHERWISE...RATHER BENIGN...ALBEIT COOLER THAN NORMAL
CONDITIONS...ARE EXPECTED FOR THE NEXT SEVERAL DAYS.
12Z MODELS SHOW SPREAD IN THE MOISTURE/THERMAL FIELDS TONIGHT
INVOF FROPA...AND AGAIN WITH LOWER AMPLITUDE WAVES IN THE MOSTLY
ZONAL FLOW LATER IN THE WEEK. OTHERWISE...AGREEMENT IS GOOD. IN THE
NEAR TERM...PLAN TO USE ACTUAL OBSERVATIONS AND EXTRAPOLATION
RATHER THAN ANY ONE MODEL SOLUTION. FURTHER OUT...AN ENSEMBLE
BLEND SHOULD CONTINUE TO BE THE BEST COURSE OF ACTION UNTIL THE
SPREAD DIMINISHES A BIT.
SHORT TERM...TONIGHT THROUGH WEDNESDAY...FRONT IS CURRENTLY MOVING
MORE QUICKLY THAN MOST OF THE MODELS INDICATED AND SEE NO REASON
WHY THIS WILL NOT CONTINUE TO BE THE CASE. WILL BE CANCELING THE
WESTERN EXTENT OF THE WIND ADVISORY AT 4 PM AS WINDS HAVE BEEN AND
SHOULD CONTINUE TO FALL BELOW ADVISORY LEVELS WITH FROPA. THE BULK
OF THE PRECIPITATION IS STILL EXPECTED ALONG AND BEHIND THE
FRONT...ASSOCIATED WITH STRONG MID LEVEL FRONTOGENESIS AND THE
APPROACH OF THE MAIN UPPER WAVE/JET. WHILE IT STILL LOOKS AS
THOUGH THE BULK OF THE PRECIPITATION SHOULD BE OVER BY THE TIME IT
IS COLD ENOUGH TO SNOW...IT SHOULD BE NOTED THAT THE LATEST NAM
AND RAP HOLD ONTO DEEPER MOISTURE INTO THE OVERNIGHT HOURS AND
WOULD POSE A GREATER SNOW RISK. HOWEVER...UPSTREAM TRENDS CONTINUE
TO AGREE WITH PREVIOUS EXPECTATION THAT THE PRECIPITATION SHOULD
END FOR THE MOST PART BEFORE IT IS COLD ENOUGH FOR SNOW. WE WILL
NEED TO KEEP AN EYE ON THESE TRENDS THOUGH...ESPECIALLY DUE TO THE
FASTER MOVEMENT OF THE FRONT AND ARRIVAL OF THE COLD AIR.
PRECIPITATION WILL BE OVER BY EARLY MONDAY AND A CHILLY AREA OF
HIGH PRESSURE WILL BUILD ACROSS THE AREA INTO MID WEEK. THIS
SURFACE HIGH...ASSOCIATED DRY AIRMASS...AND MOSTLY NEUTRAL UPPER
LEVEL FLOW SHOULD PRODUCE QUIET WEATHER THROUGH THE PERIOD.
LONG TERM...THURSDAY THROUGH SUNDAY...FOR THE MOST PART...THE
MODELS SUPPORT PREDOMINANTLY HIGH PRESSURE AT THE SURFACE AND
ZONAL/NEUTRAL UPPER LEVEL FLOW THROUGH THE WEEKEND. THE LOW LEVEL
FLOW TURNING SOUTHERLY AND GRADUALLY RISING HEIGHTS SUPPORT A SLOW
MODERATION IN TEMPERATURES...ALTHOUGH THEY WILL STILL BE COOL.
SOME SHORT WAVE ENERGY MAY IMPACT THE AREA FROM TIME TO TIME...BUT
THERE IS NOT ENOUGH OF A MODEL CONSENSUS IN THE TIMING/TRACK OF
ANY OF THESE DISCRETE WAVES TO WARRANT CARRYING POPS AT ANY POINT
IN THE EXTENDED RANGE OF THE FORECAST.
BAK
&&
.AVIATION...
ISSUED 1215 PM CST SUN NOV 11 2012
AVIATION CONCERNS REMAIN WITH THE VERY STRONG WINDS ACROSS ALL ILX
TERMINALS TODAY. SOUTHERLY WINDS 25-25KTS COMMON WITH GUSTS COMMON
OVER 40 KTS. VFR DOMINATING AHEAD OF FRONT. FRONT ALONG THE MISS
RIVER VALLEY AND TIMED TO PASS THRU FROM WEST TO EAST BTWN 00 AND
04Z. SHARP GRADIENT AND BAROCLINIC ZONE AND VERY SUDDEN WINDSHIFT
FROM SOUTHERLY TO WESTERLY WITH THE BOUNDARY. SHOWERS ALONG AND
BEHIND THE FRONT INTO THE EARLY MORNING HOURS LIKELY FOR MOST OF
CENTRAL IL. FAIRLY DEFINED CLEARING LINE EXPECTED FOR THE MORNING
WITH THE DRY SLOT SHOWING UP ON VIS SAT IMAGERY OVER THE PLAINS
TODAY.
HJS
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 8 PM CST THIS EVENING FOR ILZ038-042>046-
051>057-061>063-066>068-071>073.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1221 PM CST SUN NOV 11 2012
.DISCUSSION...
ISSUED 1039 AM CST SUN NOV 11 2012
WARM AIR ADVECTION AHEAD OF THE APPROACHING COLD FRONT EFFECTIVELY
BUMPING TEMPS UP A BIT IN THE FAR WEST. HAVE ADJUSTED THE FORECAST
MAX TEMPS...THOUGH IT WILL NOT BE LONG BEFORE THE MAX IS HIT IN
THAT REGION. FRONT RAPIDLY MOVING ACROSS THE MISS RIVER VALLEY WITH
PLENTY OF PRECIP BEHIND IT AND A RATHER SHARP DROP IN
TEMPERATURES EXPECTED FOR THE LATE AFTERNOON/EVENING HOURS. VERY
LITTLE THUNDER ASSOCIATED WITH THE RAINFALL. THE MAIN ISSUE FOR
THE FORECAST REMAINS VERY STRONG WINDS AHEAD OF THE FRONT AS THE
PRESSURE GRADIENT TIGHTENS AND 50 KT WINDS JUST OFF THE SFC MIX
DOWN THROUGH THIS MORNINGS INVERSION. WIND ADVISORY FOR ENTIRE
AREA WILL MOST DEFINITELY REMAIN. ZONE UPDATE ALREADY SENT.
&&
.AVIATION...
ISSUED 1215 PM CST SUN NOV 11 2012
AVIATION CONCERNS REMAIN WITH THE VERY STRONG WINDS ACROSS ALL ILX
TERMINALS TODAY. SOUTHERLY WINDS 25-25KTS COMMON WITH GUSTS COMMON
OVER 40 KTS. VFR DOMINATING AHEAD OF FRONT. FRONT ALONG THE MISS
RIVER VALLEY AND TIMED TO PASS THRU FROM WEST TO EAST BTWN 00 AND
04Z. SHARP GRADIENT AND BAROCLINIC ZONE AND VERY SUDDEN WINDSHIFT
FROM SOUTHERLY TO WESTERLY WITH THE BOUNDARY. SHOWERS ALONG AND
BEHIND THE FRONT INTO THE EARLY MORNING HOURS LIKELY FOR MOST OF
CENTRAL IL. FAIRLY DEFINED CLEARING LINE EXPECTED FOR THE MORNING
WITH THE DRY SLOT SHOWING UP ON VIS SAT IMAGERY OVER THE PLAINS
TODAY.
HJS
&&
.PREV DISCUSSION...
ISSUED 246 AM CST SUN NOV 11 2012
BIGGEST CHALLENGES THIS PACKAGE ARE WINDS TODAY/THIS EVENING AND
MODEL SPREAD TOWARD THE END OF THE WEEK.
SHORT TERM...TODAY AND TONIGHT
LOOKS LIKE A WINDY DAY ACROSS CENTRAL AND SOUTHEAST ILLINOIS.
THERE IS SOME SPREAD IN FORECAST WIND SPEEDS. STRONGER NAM SEEMS
MORE REASONABLE GIVEN MATCHING UP CURRENT WINDS AND THE HIGHER
RESOLUTION IN THE BOUNDARY LAYER COMPARED TO THE GLOBAL MODELS.
FORECAST GRADIENT WINDS SUGGEST SUSTAINED SPEEDS SHOULD SURPASS
ADVISORY LEVELS. EVEN THOUGH THE GFS GRIDS DO NOT INDICATED AS
HIGH OF SPEEDS AS THE NAM AND HIGH RES MODELS...MAV GUIDANCE IS
INDICATING ADVISORY CRITERIA. NAM MODEL SOUNDINGS SHOW 40+ KTS
SEVERAL HUNDRED FEET OFF THE SURFACE AND SUFFICIENT MIXING OCCURS...THE
GUST CRITERIA OF 45 KTS MAY ALSO BE SURPASSED. CLOUDS MAY LIMIT
MIXING SOME...BUT IT WONT TAKE MUCH TO TAP INTO THE HIGHER
MOMENTUM OFF THE SURFACE. 04Z HRRR SHOWS 40-50 KT GUSTS ACROSS
MOST OF THE AREA BY 19Z. LOOKS LIKE HIGHEST SPEEDS SHOULD DEVELOP
BY LATE MORNING OVER WEST CENTRAL IL AND THEN SPREAD QUICKLY
SOUTHEAST THROUGH MIDDAY AND EARLY AFTERNOON. WILL BE ISSUING WIND
ADVISORY FOR ENTIRE FORECAST AREA.
WINDS SHOULD DECREASE FROM NORTHWEST TO SOUTHEAST DURING THE
EVENING SHORTLY AFTER COLD FRONTAL PASSAGE. SPEAKING OF THE FRONT...
00Z MODEL SUITE IN GOOD AGREEMENT ON TIMING OF INCOMING COLD
FRONT AND POST-FRONTAL PRECIP. HOWEVER...MOST OF THE MODELS ARE
NOT HANDLING THE PRE-FRONTAL PRECIP CURRENTLY ALONG AND WEST OF
THE MISSISSIPPI IN THE WARM SECTOR. LATEST ECMWF(00Z) DOES HINT AT
AN AREA OF PRECIP OVER WEST CENTRAL IL AT 12Z. ORIGINALLY WAS
THINKING THAT ANY PRECIP CHANCE WOULD WAIT FOR THE FRONT...NOT
REACHING WESTERN FORECAST AREA UNTIL LATE MORNING...BUT WITH ONGOING
SHOWERS WILL INCLUDE A CHANCE OF RAIN FOR THE ENTIRE MORNING OVER
THE WEST.
LOOKS LIKE A ANAFRONT STRUCTURED FRONT AND THE BULK OF PRECIP SHOULD BE
MOSTLY ALONG AND BEHIND THE BOUNDARY. PRECIP WATER REMAINS WELL
ABOVE CLIMATOLOGY...99 PERCENTILE FOR NOVEMBER...AND ALTHOUGH THE
PERIOD OF RAIN AT ANY ONE SPOT SHOULDNT BE MORE THAN 12
HOURS...QPF SHOULD APPROACH AN INCH IN MOST AREAS WITH LOCALLY
HIGHER AMOUNTS. DESPITE MEAGER INSTABILITY...SHEAR IS IMPRESSIVE
AND MAY BE SUFFICIENT FOR ISOLATED EMBEDDED THUNDER BEHIND THE
FRONT WHICH COULD LOCALLY ENHANCE THE RAINFALL RATES.
STRONG COLD ADVECTION SURGES INTO THE AREA BEHIND THE FRONT AND
THERE MAY BE A BRIEF PERIOD OF A MIX OR A CHANGE TO SNOW BEFORE
THE PRECIP ENDS EARLY MONDAY. GROUND TEMPS SHOULD BE WARM ENOUGH
TO LIMIT ANY ACCUMULATION.
LONG TERM...MONDAY THROUGH SATURDAY
AFTER PRECIP MOVES OUT MONDAY MORNING...BIG STORY WILL BE THE
COLD ADVECTION. TEMPS WILL BE SUPPRESSED WITH HIGHS ON MONDAY
BEING SOME 20-25 DEGREES COOLER THAN SUNDAY IN MOST LOCATIONS AND
WITH BRISK WEST WINDS...WIND CHILLS WILL STAY OR FALL INTO THE 20S
AND 30S. CLEARING SHOULD SPREAD ACROSS THE AREA EARLY MONDAY. HIGH
PRESSURE CENTERS OVER ILLINOIS ON TUESDAY AND TUESDAY MORNING
SHOULD HAVE GOOD RADIATION AL COOLING CONDITIONS WITH A HARD FREEZE
LIKELY FOR MOST OF CENTRAL AND SOUTHEAST ILLINOIS.
850 MB TEMPS SLOWLY REBOUND AS THE AIR MASS MODERATES AFTER
TUESDAY AND TEMPS SHOULD REACH CLOSE TO NORMAL FOR THE LATER PART
OF THE WEEK.
MODEL SPREAD INCREASES SIGNIFICANTLY IN THE NAEFS AND OPERATIONAL
MODELS FOR THE LATER HALF OF THE WEEK WITH GENERALLY WEAK FLOW AND
ABOVE NORMAL HEIGHTS. MOST LIKELY SCENARIO SUGGESTS HIGH PRESSURE
RIDGING INTO IL FROM THE NORTHEAST KEEPING DRY WEATHER IN PLACE
INTO THE WEEKEND.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 8 PM CST THIS EVENING FOR ILZ027>031-036>038-
040>057-061>063-066>068-071>073.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1045 AM CST SUN NOV 11 2012
.DISCUSSION...
ISSUED 1039 AM CST SUN NOV 11 2012
WARM AIR ADVECTION AHEAD OF THE APPROACHING COLD FRONT EFFECTIVELY
BUMPING TEMPS UP A BIT IN THE FAR WEST. HAVE ADJUSTED THE FORECAST
MAX TEMPS...THOUGH IT WILL NOT BE LONG BEFORE THE MAX IS HIT IN
THAT REGION. FRONT RAPIDLY MOVING ACROSS THE MISS RIVER VALLEY WITH
PLENTY OF PRECIP BEHIND IT AND A RATHER SHARP DROP IN
TEMPERATURES EXPECTED FOR THE LATE AFTERNOON/EVENING HOURS. VERY
LITTLE THUNDER ASSOCIATED WITH THE RAINFALL. THE MAIN ISSUE FOR
THE FORECAST REMAINS VERY STRONG WINDS AHEAD OF THE FRONT AS THE
PRESSURE GRADIENT TIGHTENS AND 50 KT WINDS JUST OFF THE SFC MIX
DOWN THROUGH THIS MORNINGS INVERSION. WIND ADVISORY FOR ENTIRE
AREA WILL MOST DEFINITELY REMAIN. ZONE UPDATE ALREADY SENT.
HJS
&&
.AVIATION...
ISSUED 515 AM CST SUN NOV 11 2012
MAIN CONCERNS THIS FORECAST PERIOD WILL BE WITH THE STRONG SOUTH
WINDS TODAY...TIMING OF FROPA THIS EVENING AND ASSOCIATED RAIN
CHANCES ALONG IT AND POTENTIAL FOR A PERIOD OF MVFR/IFR CIGS
TONIGHT AS MUCH COLDER AIR FILTERS INTO THE AREA. 12Z ILX SOUNDING
SHOWING 50-55 KTS AROUND THE 2000 FOOT LAYER...SO WILL CONTINUE
WITH THE LLWS FOR THE NEXT COUPLE OF HOURS.
COLD FRONT CURRENTLY JUST WEST OF DES MOINES AND SHOULD CROSS THE
MISSISSIPPI RIVER BY 21Z. WE HAVE HAD SOME ISOLD SHOWERS DEVELOP
IN A BROAD WARM ADVECTION PATTERN ACROSS THE MID-MISSISSIPPI VALLEY
OVERNIGHT...WEST OF THE TAF SITES. MOST OF THAT ACTIVITY SHOULD
REMAIN WEST OF OUR AREA UNTIL THE FRONT MAKES SOME EASTWARD PROGRESS
LATER TODAY. SOUTHERLY WINDS OF 20 TO 25 KTS...WITH OCCASIONAL GUSTS
UP TO 40 KTS WILL PREVAIL OVER THE FORECAST AREA TODAY BEFORE WINDS
SWITCH INTO THE WEST EARLY THIS EVENING AT PIA AND SPI...AND BY 03Z
OVER AT KCMI. WE SHOULD SEE CIGS GRADUALLY LOWER TODAY AND DROP TO
MVFR CATEGORY BY LATE AFTN OR EARLY EVENING ALONG AND JUST BEHIND
THE COLD FRONT. FORECAST SOUNDINGS SUGGEST ABOUT A 3-6 HOUR PERIOD
OF MVFR CIGS AND POSSIBLY LOWER IN SOME OF THE HEAVIER RAINS
TONIGHT. THE PRECIP SHOULD BE SHIFTING EAST OF THE TAF SITES BY
AROUND 09Z WITH CIGS AND VSBYS SLOWLY IMPROVING IN THE 09Z-12Z TIME
FRAME.
SMITH
&&
.PREV DISCUSSION...
ISSUED 246 AM CST SUN NOV 11 2012
BIGGEST CHALLENGES THIS PACKAGE ARE WINDS TODAY/THIS EVENING AND
MODEL SPREAD TOWARD THE END OF THE WEEK.
SHORT TERM...TODAY AND TONIGHT
LOOKS LIKE A WINDY DAY ACROSS CENTRAL AND SOUTHEAST ILLINOIS.
THERE IS SOME SPREAD IN FORECAST WIND SPEEDS. STRONGER NAM SEEMS
MORE REASONABLE GIVEN MATCHING UP CURRENT WINDS AND THE HIGHER
RESOLUTION IN THE BOUNDARY LAYER COMPARED TO THE GLOBAL MODELS.
FORECAST GRADIENT WINDS SUGGEST SUSTAINED SPEEDS SHOULD SURPASS
ADVISORY LEVELS. EVEN THOUGH THE GFS GRIDS DO NOT INDICATED AS
HIGH OF SPEEDS AS THE NAM AND HIGH RES MODELS...MAV GUIDANCE IS
INDICATING ADVISORY CRITERIA. NAM MODEL SOUNDINGS SHOW 40+ KTS
SEVERAL HUNDRED FEET OFF THE SURFACE AND SUFFICIENT MIXING OCCURS...THE
GUST CRITERIA OF 45 KTS MAY ALSO BE SURPASSED. CLOUDS MAY LIMIT
MIXING SOME...BUT IT WONT TAKE MUCH TO TAP INTO THE HIGHER
MOMENTUM OFF THE SURFACE. 04Z HRRR SHOWS 40-50 KT GUSTS ACROSS
MOST OF THE AREA BY 19Z. LOOKS LIKE HIGHEST SPEEDS SHOULD DEVELOP
BY LATE MORNING OVER WEST CENTRAL IL AND THEN SPREAD QUICKLY
SOUTHEAST THROUGH MIDDAY AND EARLY AFTERNOON. WILL BE ISSUING WIND
ADVISORY FOR ENTIRE FORECAST AREA.
WINDS SHOULD DECREASE FROM NORTHWEST TO SOUTHEAST DURING THE
EVENING SHORTLY AFTER COLD FRONTAL PASSAGE. SPEAKING OF THE FRONT...
00Z MODEL SUITE IN GOOD AGREEMENT ON TIMING OF INCOMING COLD
FRONT AND POST-FRONTAL PRECIP. HOWEVER...MOST OF THE MODELS ARE
NOT HANDLING THE PRE-FRONTAL PRECIP CURRENTLY ALONG AND WEST OF
THE MISSISSIPPI IN THE WARM SECTOR. LATEST ECMWF(00Z) DOES HINT AT
AN AREA OF PRECIP OVER WEST CENTRAL IL AT 12Z. ORIGINALLY WAS
THINKING THAT ANY PRECIP CHANCE WOULD WAIT FOR THE FRONT...NOT
REACHING WESTERN FORECAST AREA UNTIL LATE MORNING...BUT WITH ONGOING
SHOWERS WILL INCLUDE A CHANCE OF RAIN FOR THE ENTIRE MORNING OVER
THE WEST.
LOOKS LIKE A ANAFRONT STRUCTURED FRONT AND THE BULK OF PRECIP SHOULD BE
MOSTLY ALONG AND BEHIND THE BOUNDARY. PRECIP WATER REMAINS WELL
ABOVE CLIMATOLOGY...99 PERCENTILE FOR NOVEMBER...AND ALTHOUGH THE
PERIOD OF RAIN AT ANY ONE SPOT SHOULDNT BE MORE THAN 12
HOURS...QPF SHOULD APPROACH AN INCH IN MOST AREAS WITH LOCALLY
HIGHER AMOUNTS. DESPITE MEAGER INSTABILITY...SHEAR IS IMPRESSIVE
AND MAY BE SUFFICIENT FOR ISOLATED EMBEDDED THUNDER BEHIND THE
FRONT WHICH COULD LOCALLY ENHANCE THE RAINFALL RATES.
STRONG COLD ADVECTION SURGES INTO THE AREA BEHIND THE FRONT AND
THERE MAY BE A BRIEF PERIOD OF A MIX OR A CHANGE TO SNOW BEFORE
THE PRECIP ENDS EARLY MONDAY. GROUND TEMPS SHOULD BE WARM ENOUGH
TO LIMIT ANY ACCUMULATION.
LONG TERM...MONDAY THROUGH SATURDAY
AFTER PRECIP MOVES OUT MONDAY MORNING...BIG STORY WILL BE THE
COLD ADVECTION. TEMPS WILL BE SUPPRESSED WITH HIGHS ON MONDAY
BEING SOME 20-25 DEGREES COOLER THAN SUNDAY IN MOST LOCATIONS AND
WITH BRISK WEST WINDS...WIND CHILLS WILL STAY OR FALL INTO THE 20S
AND 30S. CLEARING SHOULD SPREAD ACROSS THE AREA EARLY MONDAY. HIGH
PRESSURE CENTERS OVER ILLINOIS ON TUESDAY AND TUESDAY MORNING
SHOULD HAVE GOOD RADIATION AL COOLING CONDITIONS WITH A HARD FREEZE
LIKELY FOR MOST OF CENTRAL AND SOUTHEAST ILLINOIS.
850 MB TEMPS SLOWLY REBOUND AS THE AIR MASS MODERATES AFTER
TUESDAY AND TEMPS SHOULD REACH CLOSE TO NORMAL FOR THE LATER PART
OF THE WEEK.
MODEL SPREAD INCREASES SIGNIFICANTLY IN THE NAEFS AND OPERATIONAL
MODELS FOR THE LATER HALF OF THE WEEK WITH GENERALLY WEAK FLOW AND
ABOVE NORMAL HEIGHTS. MOST LIKELY SCENARIO SUGGESTS HIGH PRESSURE
RIDGING INTO IL FROM THE NORTHEAST KEEPING DRY WEATHER IN PLACE
INTO THE WEEKEND.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY UNTIL 8 PM CST THIS EVENING FOR ILZ027>031-036>038-
040>057-061>063-066>068-071>073.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
524 AM CST SUN NOV 11 2012
.DISCUSSION...
ISSUED 246 AM CST SUN NOV 11 2012
BIGGEST CHALLENGES THIS PACKAGE ARE WINDS TODAY/THIS EVENING AND
MODEL SPREAD TOWARD THE END OF THE WEEK.
SHORT TERM...TODAY AND TONIGHT
LOOKS LIKE A WINDY DAY ACROSS CENTRAL AND SOUTHEAST ILLINOIS.
THERE IS SOME SPREAD IN FORECAST WIND SPEEDS. STRONGER NAM SEEMS
MORE REASONABLE GIVEN MATCHING UP CURRENT WINDS AND THE HIGHER
RESOLUTION IN THE BOUNDARY LAYER COMPARED TO THE GLOBAL MODELS.
FORECAST GRADIENT WINDS SUGGEST SUSTAINED SPEEDS SHOULD SURPASS
ADVISORY LEVELS. EVEN THOUGH THE GFS GRIDS DO NOT INDICATED AS
HIGH OF SPEEDS AS THE NAM AND HIGH RES MODELS...MAV GUIDANCE IS
INDICATING ADVISORY CRITERIA. NAM MODEL SOUNDINGS SHOW 40+ KTS
SEVERAL HUNDRED FEET OFF THE SURFACE AND SUFFICIENT MIXING OCCURS...THE
GUST CRITERIA OF 45 KTS MAY ALSO BE SURPASSED. CLOUDS MAY LIMIT
MIXING SOME...BUT IT WONT TAKE MUCH TO TAP INTO THE HIGHER
MOMENTUM OFF THE SURFACE. 04Z HRRR SHOWS 40-50 KT GUSTS ACROSS
MOST OF THE AREA BY 19Z. LOOKS LIKE HIGHEST SPEEDS SHOULD DEVELOP
BY LATE MORNING OVER WEST CENTRAL IL AND THEN SPREAD QUICKLY
SOUTHEAST THROUGH MIDDAY AND EARLY AFTERNOON. WILL BE ISSUING WIND
ADVISORY FOR ENTIRE FORECAST AREA.
WINDS SHOULD DECREASE FROM NORTHWEST TO SOUTHEAST DURING THE
EVENING SHORTLY AFTER COLD FRONTAL PASSAGE. SPEAKING OF THE FRONT...
00Z MODEL SUITE IN GOOD AGREEMENT ON TIMING OF INCOMING COLD
FRONT AND POST-FRONTAL PRECIP. HOWEVER...MOST OF THE MODELS ARE
NOT HANDLING THE PRE-FRONTAL PRECIP CURRENTLY ALONG AND WEST OF
THE MISSISSIPPI IN THE WARM SECTOR. LATEST ECMWF(00Z) DOES HINT AT
AN AREA OF PRECIP OVER WEST CENTRAL IL AT 12Z. ORIGINALLY WAS
THINKING THAT ANY PRECIP CHANCE WOULD WAIT FOR THE FRONT...NOT
REACHING WESTERN FORECAST AREA UNTIL LATE MORNING...BUT WITH ONGOING
SHOWERS WILL INCLUDE A CHANCE OF RAIN FOR THE ENTIRE MORNING OVER
THE WEST.
LOOKS LIKE A ANAFRONT STRUCTURED FRONT AND THE BULK OF PRECIP SHOULD BE
MOSTLY ALONG AND BEHIND THE BOUNDARY. PRECIP WATER REMAINS WELL
ABOVE CLIMATOLOGY...99 PERCENTILE FOR NOVEMBER...AND ALTHOUGH THE
PERIOD OF RAIN AT ANY ONE SPOT SHOULDNT BE MORE THAN 12
HOURS...QPF SHOULD APPROACH AN INCH IN MOST AREAS WITH LOCALLY
HIGHER AMOUNTS. DESPITE MEAGER INSTABILITY...SHEAR IS IMPRESSIVE
AND MAY BE SUFFICIENT FOR ISOLATED EMBEDDED THUNDER BEHIND THE
FRONT WHICH COULD LOCALLY ENHANCE THE RAINFALL RATES.
STRONG COLD ADVECTION SURGES INTO THE AREA BEHIND THE FRONT AND
THERE MAY BE A BRIEF PERIOD OF A MIX OR A CHANGE TO SNOW BEFORE
THE PRECIP ENDS EARLY MONDAY. GROUND TEMPS SHOULD BE WARM ENOUGH
TO LIMIT ANY ACCUMULATION.
LONG TERM...MONDAY THROUGH SATURDAY
AFTER PRECIP MOVES OUT MONDAY MORNING...BIG STORY WILL BE THE
COLD ADVECTION. TEMPS WILL BE SUPPRESSED WITH HIGHS ON MONDAY
BEING SOME 20-25 DEGREES COOLER THAN SUNDAY IN MOST LOCATIONS AND
WITH BRISK WEST WINDS...WIND CHILLS WILL STAY OR FALL INTO THE 20S
AND 30S. CLEARING SHOULD SPREAD ACROSS THE AREA EARLY MONDAY. HIGH
PRESSURE CENTERS OVER ILLINOIS ON TUESDAY AND TUESDAY MORNING
SHOULD HAVE GOOD RADIATION AL COOLING CONDITIONS WITH A HARD FREEZE
LIKELY FOR MOST OF CENTRAL AND SOUTHEAST ILLINOIS.
850 MB TEMPS SLOWLY REBOUND AS THE AIR MASS MODERATES AFTER
TUESDAY AND TEMPS SHOULD REACH CLOSE TO NORMAL FOR THE LATER PART
OF THE WEEK.
MODEL SPREAD INCREASES SIGNIFICANTLY IN THE NAEFS AND OPERATIONAL
MODELS FOR THE LATER HALF OF THE WEEK WITH GENERALLY WEAK FLOW AND
ABOVE NORMAL HEIGHTS. MOST LIKELY SCENARIO SUGGESTS HIGH PRESSURE
RIDGING INTO IL FROM THE NORTHEAST KEEPING DRY WEATHER IN PLACE
INTO THE WEEKEND.
&&
.AVIATION...
ISSUED 515 AM CST SUN NOV 11 2012
MAIN CONCERNS THIS FORECAST PERIOD WILL BE WITH THE STRONG SOUTH
WINDS TODAY...TIMING OF FROPA THIS EVENING AND ASSOCIATED RAIN
CHANCES ALONG IT AND POTENTIAL FOR A PERIOD OF MVFR/IFR CIGS
TONIGHT AS MUCH COLDER AIR FILTERS INTO THE AREA. 12Z ILX SOUNDING
SHOWING 50-55 KTS AROUND THE 2000 FOOT LAYER...SO WILL CONTINUE
WITH THE LLWS FOR THE NEXT COUPLE OF HOURS.
COLD FRONT CURRENTLY JUST WEST OF DES MOINES AND SHOULD CROSS THE
MISSISSIPPI RIVER BY 21Z. WE HAVE HAD SOME ISOLD SHOWERS DEVELOP
IN A BROAD WARM ADVECTION PATTERN ACROSS THE MID-MISSISSIPPI VALLEY
OVERNIGHT...WEST OF THE TAF SITES. MOST OF THAT ACTIVITY SHOULD
REMAIN WEST OF OUR AREA UNTIL THE FRONT MAKES SOME EASTWARD PROGRESS
LATER TODAY. SOUTHERLY WINDS OF 20 TO 25 KTS...WITH OCCASIONAL GUSTS
UP TO 40 KTS WILL PREVAIL OVER THE FORECAST AREA TODAY BEFORE WINDS
SWITCH INTO THE WEST EARLY THIS EVENING AT PIA AND SPI...AND BY 03Z
OVER AT KCMI. WE SHOULD SEE CIGS GRADUALLY LOWER TODAY AND DROP TO
MVFR CATEGORY BY LATE AFTN OR EARLY EVENING ALONG AND JUST BEHIND
THE COLD FRONT. FORECAST SOUNDINGS SUGGEST ABOUT A 3-6 HOUR PERIOD
OF MVFR CIGS AND POSSIBLY LOWER IN SOME OF THE HEAVIER RAINS
TONIGHT. THE PRECIP SHOULD BE SHIFTING EAST OF THE TAF SITES BY
AROUND 09Z WITH CIGS AND VSBYS SLOWLY IMPROVING IN THE 09Z-12Z TIME
FRAME.
SMITH
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 10 AM THIS MORNING TO 8 PM CST THIS EVENING
FOR ILZ027>031-036>038-040>057-061>063-066>068-071>073.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
246 AM CST SUN NOV 11 2012
.DISCUSSION...
ISSUED 246 AM CST SUN NOV 11 2012
BIGGEST CHALLENGES THIS PACKAGE ARE WINDS TODAY/THIS EVENING AND
MODEL SPREAD TOWARD THE END OF THE WEEK.
SHORT TERM...TODAY AND TONIGHT
LOOKS LIKE A WINDY DAY ACROSS CENTRAL AND SOUTHEAST ILLINOIS.
THERE IS SOME SPREAD IN FORECAST WIND SPEEDS. STRONGER NAM SEEMS
MORE REASONABLE GIVEN MATCHING UP CURRENT WINDS AND THE HIGHER
RESOLUTION IN THE BOUNDARY LAYER COMPARED TO THE GLOBAL MODELS.
FORECAST GRADIENT WINDS SUGGEST SUSTAINED SPEEDS SHOULD SURPASS
ADVISORY LEVELS. EVEN THOUGH THE GFS GRIDS DO NOT INDICATED AS
HIGH OF SPEEDS AS THE NAM AND HIGH RES MODELS...MAV GUIDANCE IS
INDICATING ADVISORY CRITERIA. NAM MODEL SOUNDINGS SHOW 40+ KTS
SEVERAL HUNDRED FEET OFF THE SURFACE AND SUFFICIENT MIXING OCCURS...THE
GUST CRITERIA OF 45 KTS MAY ALSO BE SURPASSED. CLOUDS MAY LIMIT
MIXING SOME...BUT IT WONT TAKE MUCH TO TAP INTO THE HIGHER
MOMENTUM OFF THE SURFACE. 04Z HRRR SHOWS 40-50 KT GUSTS ACROSS
MOST OF THE AREA BY 19Z. LOOKS LIKE HIGHEST SPEEDS SHOULD DEVELOP
BY LATE MORNING OVER WEST CENTRAL IL AND THEN SPREAD QUICKLY
SOUTHEAST THROUGH MIDDAY AND EARLY AFTERNOON. WILL BE ISSUING WIND
ADVISORY FOR ENTIRE FORECAST AREA.
WINDS SHOULD DECREASE FROM NORTHWEST TO SOUTHEAST DURING THE
EVENING SHORTLY AFTER COLD FRONTAL PASSAGE. SPEAKING OF THE FRONT...
00Z MODEL SUITE IN GOOD AGREEMENT ON TIMING OF INCOMING COLD
FRONT AND POST-FRONTAL PRECIP. HOWEVER...MOST OF THE MODELS ARE
NOT HANDLING THE PRE-FRONTAL PRECIP CURRENTLY ALONG AND WEST OF
THE MISSISSIPPI IN THE WARM SECTOR. LATEST ECMWF(00Z) DOES HINT AT
AN AREA OF PRECIP OVER WEST CENTRAL IL AT 12Z. ORIGINALLY WAS
THINKING THAT ANY PRECIP CHANCE WOULD WAIT FOR THE FRONT...NOT
REACHING WESTERN FORECAST AREA UNTIL LATE MORNING...BUT WITH ONGOING
SHOWERS WILL INCLUDE A CHANCE OF RAIN FOR THE ENTIRE MORNING OVER
THE WEST.
LOOKS LIKE A ANAFRONT STRUCTURED FRONT AND THE BULK OF PRECIP SHOULD BE
MOSTLY ALONG AND BEHIND THE BOUNDARY. PRECIP WATER REMAINS WELL
ABOVE CLIMATOLOGY...99 PERCENTILE FOR NOVEMBER...AND ALTHOUGH THE
PERIOD OF RAIN AT ANY ONE SPOT SHOULDNT BE MORE THAN 12
HOURS...QPF SHOULD APPROACH AN INCH IN MOST AREAS WITH LOCALLY
HIGHER AMOUNTS. DESPITE MEAGER INSTABILITY...SHEAR IS IMPRESSIVE
AND MAY BE SUFFICIENT FOR ISOLATED EMBEDDED THUNDER BEHIND THE
FRONT WHICH COULD LOCALLY ENHANCE THE RAINFALL RATES.
STRONG COLD ADVECTION SURGES INTO THE AREA BEHIND THE FRONT AND
THERE MAY BE A BRIEF PERIOD OF A MIX OR A CHANGE TO SNOW BEFORE
THE PRECIP ENDS EARLY MONDAY. GROUND TEMPS SHOULD BE WARM ENOUGH
TO LIMIT ANY ACCUMULATION.
LONG TERM...MONDAY THROUGH SATURDAY
AFTER PRECIP MOVES OUT MONDAY MORNING...BIG STORY WILL BE THE
COLD ADVECTION. TEMPS WILL BE SUPPRESSED WITH HIGHS ON MONDAY
BEING SOME 20-25 DEGREES COOLER THAN SUNDAY IN MOST LOCATIONS AND
WITH BRISK WEST WINDS...WIND CHILLS WILL STAY OR FALL INTO THE 20S
AND 30S. CLEARING SHOULD SPREAD ACROSS THE AREA EARLY MONDAY. HIGH
PRESSURE CENTERS OVER ILLINOIS ON TUESDAY AND TUESDAY MORNING
SHOULD HAVE GOOD RADIATION AL COOLING CONDITIONS WITH A HARD FREEZE
LIKELY FOR MOST OF CENTRAL AND SOUTHEAST ILLINOIS.
850 MB TEMPS SLOWLY REBOUND AS THE AIR MASS MODERATES AFTER
TUESDAY AND TEMPS SHOULD REACH CLOSE TO NORMAL FOR THE LATER PART
OF THE WEEK.
MODEL SPREAD INCREASES SIGNIFICANTLY IN THE NAEFS AND OPERATIONAL
MODELS FOR THE LATER HALF OF THE WEEK WITH GENERALLY WEAK FLOW AND
ABOVE NORMAL HEIGHTS. MOST LIKELY SCENARIO SUGGESTS HIGH PRESSURE
RIDGING INTO IL FROM THE NORTHEAST KEEPING DRY WEATHER IN PLACE
INTO THE WEEKEND.
BARKER
&&
.AVIATION...
ISSUED 1139 PM CST SAT NOV 10 2012
VFR CONDITIONS WILL PREVAIL OVERNIGHT AT ALL TAF SITES. CLOUDS
WILL START HAS HIGH CIRRUS AND THEN LOWER CLOUDS AROUND AROUND
4KFT WILL ADVECT INTO THE REGION. CLOUD COVER WILL BEGIN AS BROKEN
IN THE WEST AT SPI AND PIA...AND SLOWLY MOVE EAST AFFECTING
DEC/BMI AND CMI. THIS WILL ALL BE AHEAD OF THE FRONT. THEN WHEN
THE FRONT AND PCPN ARRIVES...CIGS WILL DROP TO LOWER MVFR VERY
QUICKLY...AROUND 1.2-1.5KFT. VIS WILL ALSO DECREASE RAPIDLY WITH
THE PCPN. WILL START WITH VCSH THREE HOURS BEFORE THE FRONT AS
THERE COULD BE SOME ISOLATED TO SCATTERED SHOWERS IN THE WARM
SECTOR JUST AHEAD OF THE FRONT. HOWEVER...WARM AIR MASS SHOULD BE
WELL CAPPED HOLDING MOST PCPN BACK TO BE ALONG AND BEHIND THE
FRONT. WILL HAVE SHOWERS WITH VCTS ALONG AND BEHIND THE FRONT
STARTING IN THE EVENING HOURS...00Z-03Z. WINDS WILL REMAIN GUSTY
OVERNIGHT AND THEN INCREASE IN SPEED TOMORROW. LOWE LEVEL JET OF
40-45KTS NOW WILL INCREASE AS WELL TO AROUND 50+KTS...SO EVENING
WITH SLIGHTLY GUSTY WINDS ON THE SFC NOW...WILL KEEP WS OF 50KTS
GOING FOR OVERNIGHT. GUSTY WINDS WILL DECREASE JUST AHEAD OF THE
FRONT BUT THEN DECREASE MORE AS THEY SHIFT TO WEST-NORTHWESTERLY
BEHIND THE FRONT.
AUTEN
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
WIND ADVISORY FROM 10 AM THIS MORNING TO 8 PM CST THIS EVENING
FOR ILZ027>031-036>038-040>057-061>063-066>068-071>073.
&&
$$
AREA FORECAST DISCUSSION
NWS DES MOINES IA
336 PM CST SUN NOV 11 2012
.SHORT TERM /TONIGHT/...
EXTRAPOLATION AND RAP FORCING SUGGEST PRECIP WILL COME TO AN END IN
OUR FORECAST AREA BY 00Z SO NOTHING BEYOND LINGERING LIGHT
RAIN...LIGHT SLEET OR LIGHT SNOW FAR SE LATE THIS AFTERNOON AS COLD
AIR CONTINUES TO DEEPEN. HAVE HAD NO REPORTS OF ANYTHING BEYOND
TOKEN PERIODS OF LIGHT SLEET AS OF YET HOWEVER. CERTAINLY NO
ACCUMULATIONS.
SKIES SHOULD CLEAR THIS EVENING LEADING TO MIN TEMP CONCERNS.
ALTHOUGH MOS SHOWS LOWS IN THE MID TEENS AND LOWER 20S...FORECAST
SOUNDINGS SUGGEST AIRMASS WILL REMAIN MIXED THROUGH THE NIGHT WITH
PERSISTENT NW WINDS. THIS SEEMS REASONABLE SO HAVE BLENDED MOS AND
SOMEWHAT WARMER RAW MODEL TEMPS FOR LOWS.
.LONG TERM /MONDAY THROUGH /...
FEW CONCERNS WITH EXTENDED AS STRONG LOW PRESSURE SYSTEM
CONTINUES TO PUSH NE. BEHIND LOW...UPPER LEVEL FLOW WILL BE MOSTLY
ZONAL. TEMPERATURES WILL REMAIN COLD FOR MONDAY AND MONDAY NIGHT
AS COLD CANADIAN AIR REMAINS IN PLACE BEHIND STRONG COLD
FRONT...WITH LITTLE WARMING FOR MONDAY. HAVE LEFT MENTION OF
ISOLATED FLURRIES ACROSS THE NORTH MONDAY WITH WRAP AROUND OF LOW
CROSSING INTO MN. HAVE DROPPED OVERNIGHT LOWS MONDAY NIGHT AS
SKIES CLEAR AND WINDS BECOME LIGHT EXPECT GOOD RADIATIONAL
COOLING. WILL BE WAA INCREASING ACROSS THE WEST MONDAY NIGHT...BUT
WITH 850 TEMPS STILL BELOW 0C...EXPECT TEMPS TO DROP INTO THE
TEENS AND 20S. A WEAK WAVE WILL PUSH THROUGH FOR WEDNESDAY...WITH
SOUTHERLY FLOW INCREASING. WAVE WILL BRING LITTLE IMPACT WITH LACK
OF MOISTURE. TEMPERATURES WILL CONTINUE TO WARM WITH SOUTHERLY
FLOW THROUGH THE WEEK...AND WILL SEE A RETURN TO SLIGHTLY ABOVE
NORMAL TEMPERATURES FOR THE END OF THE WORK WEEK.
NEXT SYSTEM OF CONCERN REMAINS LOW PRESSURE SYSTEM DEVELOPING
ACROSS WESTERN PLAINS FOR END OF THE PERIOD. MODELS CONTINUE TO
WEAKEN AND SLOW THIS SYSTEM. HAVE CUT BACK ON POPS FOR THE
WEEKEND...KEEPING THEM CONFINED TO THE WEST AND SW FOR SATURDAY
AND SUNDAY. MODELS DO NOT HAVE GOOD AGREEMENT ON TRACK OR
PLACEMENT OF THE LOW HOWEVER...SO THIS COULD CONTINUE TO CHANCE.
STILL LOOKS LIKE BEST CHANCES FOR PRECIPITATION WILL BE BEYOND THE
FORECAST PERIOD NEXT WEEK AS LOW PUSHES EAST.
&&
.AVIATION...11/18Z
WIDESPREAD MVFR/IFR CONDITIONS PERSIST OVER FORECAST AREA WITH MUCH
OF PRECIP NOW ALONG OR JUST EAST OF KMCW-KDSM-KLWD LINE. EXPECT
PRECIP TO CONTINUE ADVANCING EASTWARD AND NOT ENDING AT KOTM UNTIL
AROUND 00Z...AND AT LEAST MVFR CIGS LINGERING FOR SEVERAL HOURS
AFTER THAT. SKIES SHOULD THEN BECOME VFR/MOSTLY CLEAR OVERNIGHT.
SUSTAINED WINDS WILL NOT DIMINISH TOO MUCH OVERNIGHT AND THEN BECOME
GUSTY AGAIN DURING MIXING LATE MON MORNING.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...SMALL
LONG TERM...AWB
AVIATION...SMALL
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1022 PM CST SAT NOV 10 2012
.UPDATE 11/06Z AVIATION DISCUSSION...
.SHORT TERM /TONIGHT/...
HAVE UPDATED WINDS OVER WESTERN IOWA FOR STRONGER SFC GRADIENT AHEAD
OF FRONT. OTHERWISE...FORECAST LOOKS TO BE ON TARGET WITH THUNDER
TIMING AND COLDER TEMPERATURES BY MORNING.
.PREVIOUS SHORT TERM /TONIGHT/...
ALL ELEMENTS ARE CONCERNS THIS EVENING WITH TREMENDOUS CHANGE IN THE
WEATHER. PARENT LONG WAVE TROUGH OF UPSTREAM SYSTEM IS STILL WEST
OF ROCKIES BUT LEAD CO AND NE SHORT WAVES CONTINUE TO PRODUCE
WIDESPREAD SURFACE PRESSURE FALLS ALONG AND AHEAD OF FRONTAL
BOUNDARY WHICH EXTENDS ACROSS NE INTO SIOUXLAND AREA AT 20Z. NO
ISALLOBARIC MAX OR PUSH EVIDENT AS OF YET SO DO NOT EXPECT MUCH
MOVEMENT FOR AWHILE. WARM SECTOR AIRMASS STILL HAS A WAYS TO GO
BEFORE BECOMING SURFACE BASED WITH 20Z SUBJECTIVE ANALYSIS SHOWING
ONLY 100 J/KG MLCAPES AND CINH ONLY DOWN TO 50 J/KG IN SMALL AREA
ACROSS KS/NE BORDER. LATEST RAP AND NAM SUGGEST ONLY A SMALL WINDOW
FOR THERMODYNAMICS FAVORABLE FOR SURFACE CONVECTION UPSTREAM THROUGH
EARLY EVENING...AND WHAT THERE IS FADES INTO THE NIGHT FARTHER
EAST SO DO NOT REALLY FEEL TORNADOES OR SURFACE BASED STORMS A
THREAT.
HOWEVER LATEST NAM/HRRR AND WRF RUNS ALL SUGGEST SIMILAR
PROGRESSIONS WITH CONVECTION DEVELOPING ACROSS ERN NE ASSOCIATED
WITH FORCING THAT IS CURRENTLY PRODUCING NE/SD SNOW. THIS MOVES
INTO WRN FORECAST AREA AFTER 03Z AND THEN ACROSS REMAINDER OF THE
AREA OVERNIGHT. MODELS ACTUALLY DEPICT FORCING MAX 06-12Z SO PRECIP
MAY ACTUALLY EXPAND EARLY SUN MORNING. WIND WOULD SEEM TO BE OUR
GREATEST SEVERE THREAT WITH STORM MOTION SW-NE 50-60KTS...BUT WITH
WANING INSTABILITY AND SOUNDINGS MOISTENING DO NOT THINK THIS IS A
BIG THREAT OVERALL. TEMPERATURES WILL BE PROBLEMATIC WITH SHARP
GRADIENT ACROSS FRONTAL BOUNDARY. TEMPS SHOULD FALL SHARPLY WITH
FRONT NW...BUT WILL LIKELY NOT REACH FAR SERN SECTIONS UNTIL BEYOND
THIS PERIOD.
.LONG TERM /SUNDAY THROUGH SATURDAY/...
MAIN FORECAST CONCERNS FOR LONG TERM FOCUS AROUND BEGINNING OF
LONG TERM AND PRECIPITATION AND TEMPERATURES FOR SUNDAY AND INTO
SUNDAY NIGHT. STRONG COLD FRONT WILL PUSH ACROSS THE CWA
THROUGHOUT THE DAY SUNDAY...AND ANTICIPATE FROPA NEAR 12Z ACROSS
THE WEST...AND AROUND 15Z FOR CENTRAL LOCATIONS. THIS WILL ALLOW
TEMPERATURES TO DROP THROUGHOUT THE DAY...WITH HIGH TEMPERATURES
OCCURRING BETWEEN VERY NEAR 12Z-15Z OR A LITTLE LATER FURTHER SE.
GOOD MOISTURE ASSOCIATED WITH FRONT AND STRONG FRONTOGENESIS AND
LIFT WILL ALLOW FOR PRECIPITATION WITH FRONT. MOST OF THIS
PRECIPITATION WILL COME AS RAIN WITH WARMER TEMPERATURES AHEAD OF
FRONT. HOWEVER...CLOSER TO THE FRONT AND LINGERING POST-FRONTAL
PRECIPITATION WILL LIKELY BE MIXED.
MIXED PRECIPITATION WILL BE MOST LIKELY ACROSS THE WEST SUNDAY
MORNING BEFORE SWITCHING OVER TO RAIN/SNOW IN THE AFTERNOON. GFS
AND NAM SOUNDINGS DIFFER SLIGHTLY WITH PRECIP TYPE AT
SURFACE...MAINLY DUE TO TIMING DIFFERENCES WITH FROPA.
HOWEVER...FEEL THERE IS A GOOD CHANCE FOR RN/IP NEAR FRONT. WITH
ICE INTRODUCTION ALOFT...FALLING THROUGH STRONG WARM LAYER...NEAR
OR ABOVE 6C...BEFORE STRONG COLD LAYER CLOSER TO SURFACE WITH
FRONT. DEPTH OF NEAR SURFACE COLD LAYER VARIES BY MODEL...BUT MOST
INDICATE A GOOD CHANCE FOR REFREEZING AND COULD SEE SLEET. SURFACE
TEMPERATURES WILL BE SLIGHTLY ABOVE FREEZING...FALLING TO NEAR
FREEZING WITH APPROACHING COLD FRONT. THEREFORE CANNOT RULE OUT
CHANCE FOR LOCALIZED FZRN. HOWEVER...FEEL THIS THREAT IS VERY
MINIMAL WITH WARM SURFACE TEMPERATURES AND SMALL TIMING WINDOW.
HOWEVER...LOCALIZED ICING ON ELEVATED SURFACES IS POSSIBLE EARLY
SUNDAY MORNING ACROSS THE NORTHWEST AND WEST. STRONG FRONT PUSHES
THROUGH QUICKLY PUSHING SOUNDING TEMPS BELOW ZERO THROUGH
COLUMN...ENDING CHANCES FOR MELTING IN WARM LAYER...WITH PRECIP AT
SURFACE CHANGING TO RN/SN MIX. AGAIN...EXPECT LITTLE IN THE WAY OF
ACCUMULATION WITH WARM SURFACE TEMPERATURES AND BULK OF
PRECIPITATION PREFRONTAL AND FALLING AS RAIN.
PRECIPITATION WILL PUSH OUT BY SUNDAY NIGHT...WITH COLD
TEMPERATURES REMAINING. COULD SEE SOME LIGHT FLURRIES ACROSS THE
NORTH MONDAY NIGHT AS LOW TRACKS ACROSS THE NORTH. HOWEVER...NOT A
LOT OF LIFT ASSOCIATED WITH THIS AND HAVE ONLY KEPT FLURRIES
MENTIONED WITH NO ACCUMULATION. FOCUS FOR THE LONG TERM SWITCHES
TO TEMPERATURES THROUGH THE WEEK AS NEARLY ZONAL FLOW SETS UP
ACROSS THE REGION. FEW WAVES WILL PUSH THROUGH THE FLOW...BUT
LITTLE MOISTURE AND HAVE NOT INCLUDED PRECIPITATION CHANCES.
TEMPERATURES WILL STEADILY WARM WITH SOUTHERLY SURFACE FLOW...WITH
HIGHS IN THE 40S AND 50S FOR THE END OF THE WEEK. MODELS CONTINUE
TO DEVELOP ANOTHER AREA OF LOW PRESSURE EAST OF THE ROCKIES FOR
LATE IN THE WEEK. HOWEVER...HAVE SIGNIFICANTLY SLOWED DOWN THIS
DEVELOPMENT AND HAVE THEREFORE CUT BACK ON PRECIPITATION CHANCES
FOR FRIDAY WITH ONLY CHANCES MENTIONED SATURDAY. MAY SEE A
CONTINUED SLOWING TREND WITH THIS SYSTEM AND WILL LIKELY SEE BEST
CHANCES FOR PRECIPITATION RETURNING AGAIN AFTER THE END OF THE
PERIOD.
&&
.AVIATION...11/06Z
AS THE FRONT CROSSES THE STATE FROM 06Z WEST TO 13Z EAST WINDS WILL
SWING AROUND TO NW DIRECTION AND INCREASE DURING THE MORNING HOURS.
SHOWERS AND ISO THUNDER WILL CONTINUE OVERNIGHT AS FRONT MOVES EAST
AND SHORT WAVE IMPULSE RIDES ALONG THE BOUNDARY NORTHEAST THROUGH
IOWA. AS COLD AIR RUSHES INTO THE BACK SIDE OF THE SYSTEM RAIN MIXES
IN WITH SNOW AND THEN CHANGES OVER TO SNOW AS THE SYSTEM DEPARTS.
WINDS WILL GRADUALLY DIMINISH TOWARD 00Z AS SFC GRADIENT WEAKENS.
CIGS WILL REMAIN RATHER LOW FOR MUCH OF THE DAY BUT LIFT TOWARD
20-00Z TIMEFRAME. WITH SYSTEM HEADING EAST WILL SEE WINDS GRADUALLY
DIMINISH THROUGH THE REMAINDER OF THE TAF FCST.
&&
.DMX WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
SHORT TERM...SMALL/REV
LONG TERM...AWB
AVIATION...REV
AREA FORECAST DISCUSSION
NWS GOODLAND KS
345 PM MST SUN NOV 11 2012
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 115 PM MST SUN NOV 11 2012
LATEST WV IMAGERY AND RUC H5 ANALYSIS SHOW LARGE POSITIVELY TILTED
TROUGH OVER THE CENTRAL US WITH ITS AXIS EXTENDING SOUTH ALONG THE
KS/CO STATE LINE AND OVER THE TX/OK PANHANDLES. AT THE SURFACE A
COLD FRONT HAS PUSHED WELL SOUTH AND EAST OF THE CWA...NOW EXTENDING
FROM NORTHERN TX AND THEN BACK TO THE NE ACROSS THE CENTRAL
MISSISSIPPI RIVER VALLEY.
LIGHT SNOW ASSOCIATED WITH H7 FRONTOGENETICAL FORCING HAS ALL BUT
ENDED WITH ONLY A FEW LINGERING FLURRIES OVER OUR SW CWA. THIS
ACTIVITY SHOULD CONTINUE TO DIMINISH THIS AFTERNOON AS SUBSIDENCE AND
A STABLE AIRMASS CONTINUES TO MOVE IN FROM WYOMING AND THE NEBRASKA
PANHANDLE WHERE CLEARING IS ALREADY OBSERVED ON SATELLITE.
WHILE THERE WILL BE A SLIGHT MODERATION OF THE AIRMASS OVER THE CWA
OVERNIGHT WE WILL STILL SEE H85 TEMPS IN THE -4C TO -1C RANGE.
CONSIDERING HOW COLD MANY LOCATIONS GOT EARLY THIS MORNING WITH ONLY
A FEW BREAKS IN CLOUD COVER AND WINDS IN THE 10 TO 20 MPH...TONIGHT
WILL ACTUALLY BE MUCH BETTER FOR COOLING WITH CLEARING SKIES AND
RELATIVELY LIGHT WINDS. RIGHT NOW I HAVE TEMPS RANGING FROM 10 TO
18F ACROSS THE CWA TONIGHT...HOWEVER I WOULD NOT BE SURPRISED IF WE
SEE TEMPERATURES A FEW DEGREES COOLER THAN THIS.
THE AIR MASS WILL CONTINUE TO MODERATE MONDAY WITH HIGH TEMPERATURES
RECOVERING TO THE UPPER 40S/LOW 50S. A VERY DRY AIRMASS WILL REMAIN
IN PLACE WHICH WILL RESULT IN RH VALUES WITHIN RED FLAG CRITERIA.
WINDS APPEAR TO BE MARGINAL SO NO RFW IS PLANNED...HOWEVER THIS MAY
NEED TO BE WATCHED IN THE EVENT THAT WINDS ARE A LITTLE STRONGER.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 115 PM MST SUN NOV 11 2012
MONDAY NIGHT-WEDNESDAY...ONE UPPER DISTURBANCE MOVES ACROSS THE AREA
TUESDAY WITH NOTHING BUT AN INCREASE IN CLOUDINESS. ANOTHER BATCH OF
CLOUDS MOVE IN WEDNESDAY AFTERNOON AND CONTINUE THROUGH THE NIGHT AS
ANOTHER SYSTEM MOVES THROUGH THE NORTHERN AND CENTRAL PLAINS.
SEASONAL HIGH TEMPERATURES WITH BELOW NORMAL TEMPERATURES MONDAY
NIGHT AND TUESDAY NIGHT...NEAR TO SLIGHTLY ABOVE NORMAL WEDNESDAY
NIGHT.
THURSDAY-SUNDAY...NOT MUCH GOING ON TIL FRIDAY NIGHT THROUGH
SATURDAY NIGHT WHEN A WEATHER SYSTEM MOVES ACROSS THE AREA. NOT MUCH
IN THE WAY OF PRECIPITATION HOWEVER. OTHERWISE SEASONAL TEMPERATURES
FOR THIS TIME OF YEAR.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING)
ISSUED AT 345 PM MST SUN NOV 11 2012
VFR THROUGH THE PERIOD AT KGLD AND KMCK. VRB WINDS AT BEGINNING OF
TAF PERIOD WILL BECOME WESTERLY AT 9-12KTS BY 06Z THEN SHIFT TO
THE W/NW AT 10-15KTS BY 17Z MONDAY AS A WEAK UPPER WAVE AND
ASSOCIATED MID AND HIGH LEVEL CLOUDS MOVE THROUGH. BY 23Z WINDS
WILL BECOME VARIABLE AT 5KTS OR LESS.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...99
AVIATION...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
115 PM MST SUN NOV 11 2012
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 115 PM MST SUN NOV 11 2012
LATEST WV IMAGERY AND RUC H5 ANALYSIS SHOW LARGE POSITIVELY TILTED
TROUGH OVER THE CENTRAL US WITH ITS AXIS EXTENDING SOUTH ALONG THE
KS/CO STATE LINE AND OVER THE TX/OK PANHANDLES. AT THE SURFACE A
COLD FRONT HAS PUSHED WELL SOUTH AND EAST OF THE CWA...NOW EXTENDING
FROM NORTHERN TX AND THEN BACK TO THE NE ACROSS THE CENTRAL
MISSISSIPPI RIVER VALLEY.
LIGHT SNOW ASSOCIATED WITH H7 FRONTOGENETICAL FORCING HAS ALL BUT
ENDED WITH ONLY A FEW LINGERING FLURRIES OVER OUR SW CWA. THIS
ACTIVITY SHOULD CONTINUE TO DIMINISH THIS AFTERNOON AS SUBSIDENCE AND
A STABLE AIRMASS CONTINUES TO MOVE IN FROM WYOMING AND THE NEBRASKA
PANHANDLE WHERE CLEARING IS ALREADY OBSERVED ON SATELLITE.
WHILE THERE WILL BE A SLIGHT MODERATION OF THE AIRMASS OVER THE CWA
OVERNIGHT WE WILL STILL SEE H85 TEMPS IN THE -4C TO -1C RANGE.
CONSIDERING HOW COLD MANY LOCATIONS GOT EARLY THIS MORNING WITH ONLY
A FEW BREAKS IN CLOUD COVER AND WINDS IN THE 10 TO 20 MPH...TONIGHT
WILL ACTUALLY BE MUCH BETTER FOR COOLING WITH CLEARING SKIES AND
RELATIVELY LIGHT WINDS. RIGHT NOW I HAVE TEMPS RANGING FROM 10 TO
18F ACROSS THE CWA TONIGHT...HOWEVER I WOULD NOT BE SURPRISED IF WE
SEE TEMPERATURES A FEW DEGREES COOLER THAN THIS.
THE AIR MASS WILL CONTINUE TO MODERATE MONDAY WITH HIGH TEMPERATURES
RECOVERING TO THE UPPER 40S/LOW 50S. A VERY DRY AIRMASS WILL REMAIN
IN PLACE WHICH WILL RESULT IN RH VALUES WITHIN RED FLAG CRITERIA.
WINDS APPEAR TO BE MARGINAL SO NO RFW IS PLANNED...HOWEVER THIS MAY
NEED TO BE WATCHED IN THE EVENT THAT WINDS ARE A LITTLE STRONGER.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 115 PM MST SUN NOV 11 2012
MONDAY NIGHT-WEDNESDAY...ONE UPPER DISTURBANCE MOVES ACROSS THE AREA
TUESDAY WITH NOTHING BUT AN INCREASE IN CLOUDINESS. ANOTHER BATCH OF
CLOUDS MOVE IN WEDNESDAY AFTERNOON AND CONTINUE THROUGH THE NIGHT AS
ANOTHER SYSTEM MOVES THROUGH THE NORTHERN AND CENTRAL PLAINS.
SEASONAL HIGH TEMPERATURES WITH BELOW NORMAL TEMPERATURES MONDAY
NIGHT AND TUESDAY NIGHT...NEAR TO SLIGHTLY ABOVE NORMAL WEDNESDAY
NIGHT.
THURSDAY-SUNDAY...NOT MUCH GOING ON TIL FRIDAY NIGHT THROUGH
SATURDAY NIGHT WHEN A WEATHER SYSTEM MOVES ACROSS THE AREA. NOT MUCH
IN THE WAY OF PRECIPITATION HOWEVER. OTHERWISE SEASONAL TEMPERATURES
FOR THIS TIME OF YEAR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1048 AM MST SUN NOV 11 2012
VFR CONDITIONS ARE EXPECTED THROUGH THE TAF PERIOD AT BOTH GLD AND
MCK. NORTHWEST FLOW ALOFT TODAY AS DEEP UPPER LEVEL TROUGH EXITS THE
CENTRAL PLAINS. A FEW HIGH CLOUDS THIS AFTERNOON WITH LIGHT WINDS
OUT OF THE NORTH-NORTHWEST...THOUGH A FEW GUSTS TO 20KTS CANNOT BE
RULED OUT. OVERNIGHT WINDS GRADUALLY BACK TO THE WEST AT
6-8KTS...AND SKIES WILL BE MOSTLY CLEAR WITH A FEW MID LEVEL CLOUDS
POSSIBLE BY SUNRISE.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
CO...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM...99
AVIATION...JJM/DR
AREA FORECAST DISCUSSION...CORRECTED AVIATION SECTION
NWS DODGE CITY KS
1153 PM CST SAT NOV 10 2012
...UPDATED FOR AVIATION...
.SYNOPSIS...
ISSUED AT 336 PM CST SAT NOV 10 2012
AN INTENSE STORM SYSTEM WAS MATURING OVER THE ROCKIES AND ADJACENT
GREAT PLAINS TODAY. AFTERNOON RAP ANALYSIS SHOWED A 400MB JET STREAK
OF 100+ KNOTS EXTENDING CYCLONICALLY FROM NORTHEASTERN NEW MEXICO
THROUGH CENTRAL ARIZONA INTO CENTRAL CALIFORNIA. THIS SIGNIFICANT
CYCLONICALLY CURVED JET HAS HELPED SPAWN A DEEP SURFACE LOW AROUND
993MB OVER EASTERN COLORADO THIS AFTERNOON. LOWER-MID TROPOSPHERIC
WIND SPEEDS FROM THE SOUTHWEST WERE 50 TO 70 KNOTS, WHICH WAS THE
TOP OF THE MIXED LAYER IN MANY PLACES ACROSS THE HIGH PLAINS. THIS
LED TO WIDESPREAD SURFACE HIGH WIND EVENT WITH NUMEROUS OBS GUSTING
50 TO EVEN 60 KNOTS AT TIMES. MOST IMPRESSIVELY WAS A RECENT
OBSERVATION AT TUCUMCARI NEW MEXICO OF A 64 KNOT GUST. WIDESPREAD
BLOWING DUST WAS ALSO OCCURRING WITHIN THE HIGH WIND AREA,
EXACERBATED BY THE LONG TERM DROUGHT CONDITIONS. A SHALLOW, NEARLY
STATIONARY SURFACE FRONT THIS MORNING LIFTED BACK NORTH FROM
NORTHWEST KANSAS INTO CENTRAL NEBRASKA AS A WARM FRONT WITH THE
SURFACE LOW STRENGTHENING. THIS QUASI-STATIONARY FRONT AT 19Z
EXTENDED FROM THE 993MB SURFACE LOW NORTHEAST OF LA JUNTA, COLORADO
TO NEAR GOODLAND, KS TO COLUMBUS, NE. THE SURFACE BAROCLINIC ZONE
WAS VERY IMPRESSIVE WITH A TEMPERATURE OF 17F AT CASPER, WYOMING
NORTH OF THE FRONT IN THE ARCTIC AIRMASS AND 79F AT HAYS, KANSAS.
&&
.SHORT TERM...(THIS EVENING AND OVERNIGHT)
ISSUED AT 336 PM CST SAT NOV 10 2012
THE HIGH WIND EVENT WILL CONTINUE WEST OF THE DRYLINE THROUGH 23Z OR
SO, AT WHICH POINT WINDS WILL SLOWLY SLACKEN OFF WITH DUST SETTLING.
AS FAR AS THE PRECIPITATION CHANCES GO, NO CHANGE IN THE CURRENT
FORECAST IS EXPECTED. DEWPOINT TEMPERATURES HAVE NOT BEEN ANY HIGHER
THAN THE MID 50S, WHICH RESULTED IN CAPE 800-1000 J/KG. DESPITE THE
VERY IMPRESSIVE LOW LEVEL AND DEEP LAYER SHEAR, THE LACK OF
APPRECIABLE INSTABILITY AND LOW LEVEL MOISTURE SHOULD PRECLUDE
WIDESPREAD SEVERE WEATHER. THAT BEING SAID, INTENSE MID LEVEL COLD
ADVECTION WILL BE INCREASING, ALLOWING CAPE PROFILES TO IMPROVE THIS
EVENING. WINDOW FOR SEVERE WEATHER SHOULD BE DURING THE 00-04Z TIME
FRAME, WITH THE LINE OF FORCING AND PACIFIC COLD FRONT MOVING
THROUGH SOUTHWEST KANSAS/WESTERN PORTIONS OF SOUTH CENTRAL KANSAS.
THE CANADIAN COLD FRONT WILL BE MOVING THROUGH DURING THE 09-12Z
TIME FRAME ACROSS SOUTHWEST KANSAS, AT WHICH POINT WE WILL SEE
STRONG COLD AIR ADVECTION WITH -8 TO -11C 850MB TEMPERATURES DRIVING
SOUTH. THERE WILL BE SLIGHT DOWNSLOPE MODIFICATION OF THIS AIRMASS
AS WESTERLY COMPONENT MOMENTUM INCREASES OFF THE ROCKIES OF COLORADO
AND WYOMING. WITH THE ADVECTION OF THE MODIFIED ARCTIC AIRMASS, LOW
STRATUS MAY BE A CONCERN AND WILL BUMP UP THE SKY GRIDS A LITTLE BIT
TO ACCOUNT FOR A LITTLE MORE CLOUD THAN EARLIER THOUGHT WITH THE
INITIAL ONSET OF THE COLD AIR AROUND 09Z OR SO.
.LONG TERM...(SUNDAY THROUGH SATURDAY)
ISSUED AT 336 PM CST SAT NOV 10 2012
COLD AIR WILL INVADE WESTERN KANSAS BEHIND THE FRONT BY EARLY SUNDAY
MORNING. HOWEVER, SOME DOWNSLOPE MODIFICATION ON THE WESTERN EDGE OF
THE COLD AIRMASS WILL ALLOW TEMPERATURES TO RISE INTO THE LOWER TO
MID 40S IN MOST LOCATIONS. THE COLDEST NIGHT SO FAR THIS FALL IS
EXPECTED BY SUNDAY NIGHT AS WINDS DECREASE AND CLOUD COVER THINS.
LOWS SHOULD BE IN THE UPPER TEENS TO LOWER 20S BY MONDAY MORNING.
FAIRLY CHILLY AIR WILL PERSIST ON MONDAY AS THE COLD SURFACE HIGH
PRESSURE WILL STILL BE JUST OFF TO THE SOUTHEAST, WITH SEA LEVEL
PRESSURES STILL AROUND 1030MB OVER WESTERN KANSAS. HIGHS SHOULD
ONLY REACH INTO THE UPPER 40S TO LOWER 50S. ANOTHER COLD NIGHT
CAN BE EXPECTED MONDAY NIGHT AS SURFACE HIGH PRESSURE LINGERS TO OUR
EAST. LOWS OUGHT TO BE IN THE 20S.
MAINLY ZONAL MID TO HIGH LEVEL FLOW CAN BE EXPECTED TUESDAY THROUGH
SATURDAY. WEAK LEE TROUGHING WILL DEVELOP IN RESPONSE TO THE
MID-LEVEL DOWNSLOPE FLOW ON TUESDAY AND PERSIST INTO THURSDAY. THIS
WILL LEAD TO SOUTHERLY LOW LEVEL WINDS AND WARMER HIGHS IN THE UPPER
50S AND LOWER 60S. SOME BOUNDARY LAYER DECOUPLING CAN BE EXPECTED
EACH NIGHT GIVEN THE RATHER WEAK PRESSURE GRADIENT. AND GIVEN THE
RELATIVELY DRY AIR AT LOWER LEVELS, TEMPERATURES SHOULD HAVE NO
PROBLEM FALLING INTO THE 30S EACH NIGHT THROUGH FRIDAY. SOME 20S
CANNOT BE RULED OUT IN LOW-LYING AREAS.
A SHORTWAVE TROUGH IS ADVERTISED BY THE VARIOUS MODELS TO APPROACH
THE PLAINS BY LATE FRIDAY INTO SATURDAY. GIVEN THE PROGRESSIVENESS
OF THIS SYSTEM, PRECIPITATION IS NOT LIKELY AS LOW-LEVEL MOISTURE
WILL NOT MAKE IT THIS FAR WEST. HOWEVER, SINCE THE MODELS DO SHOW
SOME MID-LEVEL MOISTURE, ISENTROPIC LIFT AND SMALL AMOUNTS OF QPF,
VERY SMALL CHANCES FOR RAIN WERE MAINTAINED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1150 PM CST SAT NOV 10 2012
11-3.9 MICRON SATELLITE IMAGERY AND METAR OBSERVATIONS INDICATE
WIDESPREAD MVFR STRATUS IS RAPIDLY SPREADING SOUTHWARD ACROSS WEST
CENTRAL KANSAS. THE SOUTHWARD SPEED OF THE LEADIND EDGE INDICATES
THE STRATUS IS LIKELY TO IMPACT THE KGCK AND KDDC TERMINALS BEFORE
08 UTC. THE WIDESPREAD EXTENT OF THE STRATUS SHOULD BE ENOUGH TO
MAINTAIN HIGH CONFIDENCE IN LOW STRATUS THROUGH THE MORNING UNTIL
STRONG INSOLATION BEGINS TO WARM THE LOWER BOUNDARY LAYER.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 31 44 21 52 / 10 0 0 0
GCK 28 43 19 52 / 10 0 0 0
EHA 28 44 21 51 / 10 10 10 0
LBL 30 44 20 52 / 10 10 10 0
HYS 30 42 19 51 / 10 0 0 0
P28 40 46 23 52 / 50 0 10 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...UMSCHEID
SHORT TERM...UMSCHEID
LONG TERM...FINCH
AVIATION...RUSSELL
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1151 PM CST SAT NOV 10 2012
...UPDATED FOR AVIATION...
.SYNOPSIS...
ISSUED AT 336 PM CST SAT NOV 10 2012
AN INTENSE STORM SYSTEM WAS MATURING OVER THE ROCKIES AND ADJACENT
GREAT PLAINS TODAY. AFTERNOON RAP ANALYSIS SHOWED A 400MB JET STREAK
OF 100+ KNOTS EXTENDING CYCLONICALLY FROM NORTHEASTERN NEW MEXICO
THROUGH CENTRAL ARIZONA INTO CENTRAL CALIFORNIA. THIS SIGNIFICANT
CYCLONICALLY CURVED JET HAS HELPED SPAWN A DEEP SURFACE LOW AROUND
993MB OVER EASTERN COLORADO THIS AFTERNOON. LOWER-MID TROPOSPHERIC
WIND SPEEDS FROM THE SOUTHWEST WERE 50 TO 70 KNOTS, WHICH WAS THE
TOP OF THE MIXED LAYER IN MANY PLACES ACROSS THE HIGH PLAINS. THIS
LED TO WIDESPREAD SURFACE HIGH WIND EVENT WITH NUMEROUS OBS GUSTING
50 TO EVEN 60 KNOTS AT TIMES. MOST IMPRESSIVELY WAS A RECENT
OBSERVATION AT TUCUMCARI NEW MEXICO OF A 64 KNOT GUST. WIDESPREAD
BLOWING DUST WAS ALSO OCCURRING WITHIN THE HIGH WIND AREA,
EXACERBATED BY THE LONG TERM DROUGHT CONDITIONS. A SHALLOW, NEARLY
STATIONARY SURFACE FRONT THIS MORNING LIFTED BACK NORTH FROM
NORTHWEST KANSAS INTO CENTRAL NEBRASKA AS A WARM FRONT WITH THE
SURFACE LOW STRENGTHENING. THIS QUASI-STATIONARY FRONT AT 19Z
EXTENDED FROM THE 993MB SURFACE LOW NORTHEAST OF LA JUNTA, COLORADO
TO NEAR GOODLAND, KS TO COLUMBUS, NE. THE SURFACE BAROCLINIC ZONE
WAS VERY IMPRESSIVE WITH A TEMPERATURE OF 17F AT CASPER, WYOMING
NORTH OF THE FRONT IN THE ARCTIC AIRMASS AND 79F AT HAYS, KANSAS.
&&
.SHORT TERM...(THIS EVENING AND OVERNIGHT)
ISSUED AT 336 PM CST SAT NOV 10 2012
THE HIGH WIND EVENT WILL CONTINUE WEST OF THE DRYLINE THROUGH 23Z OR
SO, AT WHICH POINT WINDS WILL SLOWLY SLACKEN OFF WITH DUST SETTLING.
AS FAR AS THE PRECIPITATION CHANCES GO, NO CHANGE IN THE CURRENT
FORECAST IS EXPECTED. DEWPOINT TEMPERATURES HAVE NOT BEEN ANY HIGHER
THAN THE MID 50S, WHICH RESULTED IN CAPE 800-1000 J/KG. DESPITE THE
VERY IMPRESSIVE LOW LEVEL AND DEEP LAYER SHEAR, THE LACK OF
APPRECIABLE INSTABILITY AND LOW LEVEL MOISTURE SHOULD PRECLUDE
WIDESPREAD SEVERE WEATHER. THAT BEING SAID, INTENSE MID LEVEL COLD
ADVECTION WILL BE INCREASING, ALLOWING CAPE PROFILES TO IMPROVE THIS
EVENING. WINDOW FOR SEVERE WEATHER SHOULD BE DURING THE 00-04Z TIME
FRAME, WITH THE LINE OF FORCING AND PACIFIC COLD FRONT MOVING
THROUGH SOUTHWEST KANSAS/WESTERN PORTIONS OF SOUTH CENTRAL KANSAS.
THE CANADIAN COLD FRONT WILL BE MOVING THROUGH DURING THE 09-12Z
TIME FRAME ACROSS SOUTHWEST KANSAS, AT WHICH POINT WE WILL SEE
STRONG COLD AIR ADVECTION WITH -8 TO -11C 850MB TEMPERATURES DRIVING
SOUTH. THERE WILL BE SLIGHT DOWNSLOPE MODIFICATION OF THIS AIRMASS
AS WESTERLY COMPONENT MOMENTUM INCREASES OFF THE ROCKIES OF COLORADO
AND WYOMING. WITH THE ADVECTION OF THE MODIFIED ARCTIC AIRMASS, LOW
STRATUS MAY BE A CONCERN AND WILL BUMP UP THE SKY GRIDS A LITTLE BIT
TO ACCOUNT FOR A LITTLE MORE CLOUD THAN EARLIER THOUGHT WITH THE
INITIAL ONSET OF THE COLD AIR AROUND 09Z OR SO.
.LONG TERM...(SUNDAY THROUGH SATURDAY)
ISSUED AT 336 PM CST SAT NOV 10 2012
COLD AIR WILL INVADE WESTERN KANSAS BEHIND THE FRONT BY EARLY SUNDAY
MORNING. HOWEVER, SOME DOWNSLOPE MODIFICATION ON THE WESTERN EDGE OF THE
COLD AIRMASS WILL ALLOW TEMPERATURES TO RISE INTO THE LOWER TO MID
40S IN MOST LOCATIONS. THE COLDEST NIGHT SO FAR THIS FALL IS EXPECTED
BY SUNDAY NIGHT AS WINDS DECREASE AND CLOUD COVER THINS. LOWS SHOULD
BE IN THE UPPER TEENS TO LOWER 20S BY MONDAY MORNING.
FAIRLY CHILLY AIR WILL PERSIST ON MONDAY AS THE COLD SURFACE HIGH
PRESSURE WILL STILL BE JUST OFF TO THE SOUTHEAST, WITH SEA LEVEL
PRESSURES STILL AROUND 1030MB OVER WESTERN KANSAS. HIGHS SHOULD
ONLY REACH INTO THE UPPER 40S TO LOWER 50S. ANOTHER COLD NIGHT
CAN BE EXPECTED MONDAY NIGHT AS SURFACE HIGH PRESSURE LINGERS TO OUR
EAST. LOWS OUGHT TO BE IN THE 20S.
MAINLY ZONAL MID TO HIGH LEVEL FLOW CAN BE EXPECTED TUESDAY THROUGH
SATURDAY. WEAK LEE TROUGHING WILL DEVELOP IN RESPONSE TO THE
MID-LEVEL DOWNSLOPE FLOW ON TUESDAY AND PERSIST INTO THURSDAY. THIS
WILL LEAD TO SOUTHERLY LOW LEVEL WINDS AND WARMER HIGHS IN THE UPPER
50S AND LOWER 60S. SOME BOUNDARY LAYER DECOUPLING CAN BE EXPECTED
EACH NIGHT GIVEN THE RATHER WEAK PRESSURE GRADIENT. AND GIVEN THE
RELATIVELY DRY AIR AT LOWER LEVELS, TEMPERATURES SHOULD HAVE NO
PROBLEM FALLING INTO THE 30S EACH NIGHT THROUGH FRIDAY. SOME 20S
CANNOT BE RULED OUT IN LOW-LYING AREAS.
A SHORTWAVE TROUGH IS ADVERTISED BY THE VARIOUS MODELS TO APPROACH
THE PLAINS BY LATE FRIDAY INTO SATURDAY. GIVEN THE PROGRESSIVENESS
OF THIS SYSTEM, PRECIPITATION IS NOT LIKELY AS LOW-LEVEL MOISTURE
WILL NOT MAKE IT THIS FAR WEST. HOWEVER, SINCE THE MODELS DO SHOW
SOME MID-LEVEL MOISTURE, ISENTROPIC LIFT AND SMALL AMOUNTS OF QPF,
VERY SMALL CHANCES FOR RAIN WERE MAINTAINED.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1150 PM CST SAT NOV 10 2012
1-3.9 MICRON SATELLITE IMAGERY AND METAR OBSERVATIONS INDICATE
WIDESPREAD MVFR STRATUS IS RAPIDLY SPREADING SOUTHWARD ACROSS WEST
CENTRAL KANSAS. THE SOUTHWARD SPEED OF THE LEADIND EDGE INDICATES
THE STRATUS IS LIKELY TO IMPACT THE KGCK AND KDDC TERMINALS BEFORE
08 UTC. THE WIDESPREAD EXTENT OF THE STRATUS SHOULD BE ENOUGH TO
MAINTAIN HIGH CONFIDENCE IN LOW STRATUS THROUGH THE MORNING UNTIL
STRONG INSOLATION BEGINS TO WARM THE LOWER BOUNDARY LAYER.
&&
.PRELIMINARY POINT TEMPS/POPS...
DDC 31 44 21 52 / 10 0 0 0
GCK 28 43 19 52 / 10 0 0 0
EHA 28 44 21 51 / 10 10 10 0
LBL 30 44 20 52 / 10 10 10 0
HYS 30 42 19 51 / 10 0 0 0
P28 40 46 23 52 / 50 0 10 0
&&
.DDC WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...UMSCHEID
SHORT TERM...UMSCHEID
LONG TERM...FINCH
AVIATION...RUSSELL
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
925 PM EST MON NOV 12 2012
.UPDATE...
ISSUED AT 924 PM EST MON NOV 12 2012
MAIN UPDATE CONCERN DEALS WITH HEAVIER SNOW BAND WHICH HAS REACHED
INTO THE NORTHERN PORTION OF BARAGA COUNTY THIS EVENING PER MQT
RADAR LOOP. SPOTTER REPORTS FROM NEAR PELKIE TO BARAGA HAVE COME IN
WITH BETWEEN 2 AND 3 INCHES THUS FAR. GIVEN THAT RADAR CONTINUES TO
SHOW 30 DBZ REFLECTIVITY RETURNS WITH SNOW BAND OVER NW BARAGA
COUNTY AND THAT MESOSCALE MODELS SUGGEST POTENTIAL FOR THIS SNOW TO
CONTINUE FOR AT LEAST A FEW MORE HRS...DECIDED TO INCLUDE BARAGA
COUNTY IN WINTER WX ADVISORY FOR 2 TO 5 INCHES OF SNOW. HEAVIER SNOW
HAS TAPERED OFF OVER THE KEWEENAW PENINSULA WITH MAIN BAND NOW
SHIFTING SOUTH OVER NRN ONTONAGON...SRN HOUGHTON AND BARAGA
COUNTIES. LOOK FOR SNOW TO TAPER OFF LATE TONIGHT AS RDGG MOVES IN
FM THE WEST AND SUBSIDENCE INVERSION LOWERS FROM NEAR 8KFT TO BLO
5KFT.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 405 PM EST MON NOV 12 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A HIGH AMPLITUDE BUT
WEAKENING TROF EXTENDING FROM NRN ONTARIO THRU THE MISSISSIPPI
VALLEY. UNDERNEATH TROF EARLIER TODAY...12Z SOUNDINGS AT KINL/KMPX
SHOWED A DEEP MOISTURE PROFILE WITH 850MB TEMPS AROUND -15C WHICH
WILL ALLOW FOR A NICE INTERSECTION OF LAKE CONVECTION THRU THE DGZ.
SO...CONDITIONS ARE FAVORABLE FOR MDT/HVY LAKE EFFECT/LAKE ENHANCED
SNOW AS MID LEVEL TROF CONTINUES TO MOVE ACROSS THE UPPER GREAT
LAKES LATE THIS AFTN/EVENING. AS EXPECTED...A DOMINANT LES BAND
DEVELOPED OVER WRN LAKE SUPERIOR EARLIER TODAY BTWN THE MN NORTH
SHORE AND WISCONSIN`S BAYFIELD PENINSULA. WITH MID LEVEL TROF
PASSING...WINDS OVER WRN LAKE SUPERIOR ARE NOW VEERING MORE WRLY...
SO THIS DOMINANT LES BAND IS ADJUSTING TO THE CHANGING WIND...BUT IT
IS ALSO BECOMING LESS ORGANIZED...WHICH MAY BE PARTLY DUE TO
NEGATIVE DIURNAL AFFECTS. KMQT/KDLH AND ENVIRONMENT CANADA RADAR
LOCATED JUST N OF THUNDER BAY ALL INDICATE AREAS OF HEAVY LES NOW
NEARING THE WRN SHORE OF THE KEWEENAW. KDLH RADAR IS STILL SHOWING
RETURNS AS HIGH AS AROUND 12KFT...SO LAKE EFFECT CONVECTION REMAINS
DEEP WITH POCKETS OF VERY HVY SNOW. AHEAD OF THE HEAVIER SNOW...SHSN
HAVE BEEN AFFECTING PORTIONS OF THE KEWEENAW TODAY. HOWEVER...ONLY
WEBCAM THAT HAS CONSISTENTLY SHOWN SHARPLY REDUCED VIS AT TIMES IS
LOCATED ALONG THE SHORE WEST OF EAGLE RIVER.
FCST THINKING HASN`T CHANGED MUCH WITH REGARD TO LES AND HEADLINES
TONIGHT. DEEP MOISTURE AND FAVORABLE TEMP PROFILE ARGUES FOR MDT TO
HVY SNOW AT TIMES AS MID LEVEL TROF PASSES TONIGHT. BULK OF SNOW
ACCUMULATIONS ON THE KEWEENAW PENINSULA WILL OCCUR OVER THE NEXT
SEVERAL HRS AS WIND SHIFT/CONVERGENCE ZONE OVER THE WRN LAKE DROP S
ACROSS THE PENINSULA. MAY SEE SNOWFALL RATES BRIEFLY AS HIGH AS
2-4IN/HR. AFTER THE CONVERGENCE ZONE PASSES...WIND PARALLEL BANDS
WITH MUCH MORE VARIABLE SNOW INTENSITY WILL SET UP FOR THE REMAINDER
OF THE EVENING. LES WILL THEN QUICKLY DIMINISH OVERNIGHT AS SHARP
HEIGHT RISES OCCUR IN THE WAKE OF MID LEVEL TROF (180-200M HEIGHT
RISES AT 500MB BTWN 00Z AND 12Z)...INVERSION QUICKLY DROPS TO 4-5KFT
AND CONVECTIVE LAYER BEGINS TO FALL BLO THE DGZ. GIVEN THE SHORT
RESIDENCE TIME OF THE CONVERGENCE ZONE OVER THE KEWEENAW...AND
RATHER QUICK DIMINISHING TREND THRU THE NIGHT...HAVE LOWERED SNOW
AMOUNTS BY AN INCH OR TWO. MAX AMOUNTS WILL PROBABLY BE IN THE 4-5
INCH RANGE OVER THE HIGH TERRAIN.
FARTHER S...CONVERGENCE ZONE WILL SINK S AND AFFECT ONTONAGON/SRN
HOUGHTON COUNTIES THIS EVENING. ALTHOUGH PREVIOUSLY DISCUSSED
NEGATIVE FACTORS TAKE HOLD DURING THE NIGHT TO DIMINISH LES
INTENSITY...LOW-LEVEL WINDS WILL MAINTAIN A CONVERGENT LOOK AS WSW
LAND BREEZE ENHANCED WINDS OFF NW WI CONVERGE WITH WNW FLOW OVER
LAKE SUPERIOR. THIS SHOULD HELP TO AT LEAST MAINTAIN MORE PERSISTENT
THOUGH WEAKENING LES ACROSS ONTONAGON/SRN HOUGHTON COUNTIES AND
PROBABLY A SMALL PART OF GOGEBIC COUNTY N OF M-28 THRU THE NIGHT.
WILL RETAIN ADVY FOR ONTONAGON/SRN HOUGHTON COUNTIES TONIGHT.
TO THE E...WIND SHIFT/CONVERGENT BAND WILL EVENTUALLY MOVE ONSHORE
OVER THE NE FCST AREA TONIGHT. HOWEVER...BY THE TIME IT DOES...DEEP
MOISTURE WILL BE EXITING WITH SHARP HEIGHT RISES OCCURRING. SO...
WHILE THERE WILL LIKELY BE A BRIEF PERIOD OF MDT/HVY SNOW ON WIND
SHIFT...LES THAT ORGANIZES BEHIND TROF WILL NOT BE SUBSTANTIAL. WILL
PAINT 1-3 INCH ACCUMULATIONS ACROSS ALGER COUNTY E OF MUNISING AND
NRN LUCE COUNTY TONIGHT.
LINGERING LES WILL QUICKLY WIND DOWN/END FROM W TO E TUE. MIGHT SEE
AN ADDITIONAL INCH OF SNOW OVER ERN ALGER/NRN LUCE COUNTY IN THE
MORNING. OTHERWISE...LOOK FOR DECREASING CLOUDS FROM SW TO NE AS
WINDS BACK TO THE SW.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 405 PM EST MON NOV 12 2012
UPPER TROUGH THAT HAS LED TO THE UNSETTLED WEATHER THIS WEEKEND AND
TODAY WILL BE SHIFTING EAST OF THE UPPER GREAT LAKES ON TUESDAY
NIGHT. THIS WILL LEAD TO THE START OF SPLIT FLOW ACROSS MUCH OF THE
COUNTRY...WHICH WILL REALLY BECOME ESTABLISHED ON BY THE WEEKEND
BEHIND A WEAKER TROUGH MOVING THROUGH THE NORTHERN STREAM WEDNESDAY
INTO FRIDAY. THIS WILL LEAD TO A FAIRLY QUIET PATTERN ACROSS THE
UPPER GREAT LAKES FOR THE LONG TERM PERIOD.
HIGH PRESSURE RIDGE WILL BE OVER THE AREA AT THE START OF THE LONG
TERM PERIOD FROM HIGH PRESSURE CENTERED OVER THE LOWER GREAT LAKES
AND OHIO RIVER VALLEY. MOSTLY CLEAR SKIES TO START THE EVENING WILL
QUICKLY GIVE WAY TO INCREASING CLOUDS OVER THE WEST/CENTRAL...WHILE
ANY LINGERING LAKE EFFECT SHOWERS SHOULD BE PUSHING NE OVER EASTERN
LAKE SUPERIOR. THESE CLOUDS ARE IN ADVANCE OF A WEAK SHORTWAVE AND
WARM AIR ADVECTION THAT WILL MOVE ACROSS THE WESTERN CWA WEDNESDAY.
MODELS ARE CONSISTENT ON MOST OF THE MOISTURE STAYING ABOVE
H800...WITH BROAD AND WEAK LIFT ASSOCIATED WITH IT. THERE IS SOME
DRY AIR BELOW H800...BUT NOTHING TOO SUBSTANTIAL...SO THINK THAT
ANY PRECIPITATION THAT DOES FALL WILL MAKE IT TO THE SURFACE. WITH
THE BEST FORCING OVER WESTERN LAKE SUPERIOR...EXPECT THAT AREA TO
HAVE THE BEST CHANCE OF SHOWERS...SO HAVE SPREAD THE SLIGHT CHANCES
FARTHER SOUTH TO COVER MUCH OF WESTERN LAKE SUPERIOR ON WEDNESDAY.
OTHERWISE...THE MID CLOUDS WILL COVER THE REST OF THE CWA WITH ONLY
AN ISOLATED FLURRY OVER WESTERN UPPER MICHIGAN.
ONE OTHER ITEM OF NOTE FOR LATE TUESDAY NIGHT AND INTO WEDNESDAY
IS THE POTENTIAL FOR LAKE EFFECT PRECIPITATION OFF LAKE MICHIGAN.
DELTA T VALUES AROUND 15 WOULD SUPPORT LAKE ENHANCED PRECIPITATION
UNDER THE SLOWLY BACKING WINDS FROM SW TO SOUTHERLY ON WEDNESDAY.
MAIN LIMITING FACTOR APPEARS TO BE INVERSION HEIGHTS AROUND
4-5KFT. THERE ARE SOME HINTS IN THE MODELS THAT THIS INVERSION COULD
WEAKEN AS THE DEEPER MOISTURE ARRIVES AND LEAD TO AN INCREASE IN
INTENSITY. THIS LOOKS TO BE FAIRLY SHORT LIVED...AS DRIER
AIR BETWEEN H875-700 AND WAA MOVES BACK IN DURING THE AFTERNOON AND
DIMINISHES THE CHANCES AGAIN. WILL CONTINUE TO MENTION THE SLIGHT
CHANCES FOR THIS POTENTIAL...BUT SEEMS TO BE FAIRLY LIMITED.
THE SHORTWAVE MOVES AWAY FROM THE AREA WHILE A LOW PRESSURE SYSTEM
MOVES INTO HUDSON BAY. THIS SHOULD LEAD TO INCREASING SOUTHERLY
FLOW AHEAD OF A WEAK COLD FRONT MOVING INTO WESTERN ONTARIO. EXPECT
MID CLOUDS TO INCREASE AHEAD OF THIS FRONT ON WEDNESDAY
NIGHT...ESPECIALLY OVER THE NORTH HALF OF THE CWA. BOTH NAM/SREF
INDICATING INCREASED PROBABILITIES OF FOG OVER THE WEST...BUT THE
NAM HAS THINNER MID CLOUDS...WHICH WOULD LEAD BETTER RADIATIONAL
COOLING AND FOG POTENTIAL. WITH THE DIFFERENCES DIFFERENCES
IN THE MID CLOUDS...WILL LEAVE FOG MENTION OUT OF THE FORECAST DUE
TO THE POTENTIAL FOR MID CLOUDS.
DECAYING FRONTAL BOUNDARY WILL BE MOVING ACROSS THE NORTHERN HALF OF
THE CWA ON THURSDAY. THIS WILL LARGELY BE MARKED BY A WIND SHIFT AND
CLOUDS WHILE THE PRECIPITATION WILL STAY TO THE NORTH OF LAKE
SUPERIOR AND CLOSER TO THE BETTER FORCING/MOISTURE.
BEHIND THIS FRONTAL BOUNDARY AND WEAK UPPER TROUGH...SPLIT FLOW
REALLY SETTLES OVER THE NORTHERN HALF OF THE CONUS. THE SOUTHERN
STREAM JET LOOKS TO REMAIN OVER THE SOUTHERN TIER OF STATES...WHILE
THE NORTHERN STREAM RIDGES OVER NORTHERN CANADA. THIS SHOULD LEAD TO
A VERY QUIET AND LIKELY ABOVE NORMAL TEMPERATURE PERIOD FOR UPPER
MICHIGAN INTO NEXT WEEK. AT THE SURFACE...HIGH PRESSURE WILL SETTLE
OVER THE GREAT LAKES REGION FOR THURSDAY NIGHT INTO SATURDAY BEFORE
MOVING EAST INTO QUEBEC FOR SUNDAY AND MONDAY. DRY AIR ASSOCIATED
WITH THIS HIGH SHOULD PRODUCE DECREASING CLOUDS ON THURSDAY NIGHT
AND FRIDAY AND THEN PARTLY CLOUDY TO MOSTLY CLEAR SKIES INTO NEXT
WEEK. BIGGEST QUESTION WILL BE THE TEMPERATURES...AS THEY WILL
DEPEND ON HOW DEEP THE MIXING WILL BE. BOTH GFS/ECMWF INDICATING
H850 TEMPS RISING TOWARDS 1-2C THIS WEEKEND...BUT BOTH ARE
STRUGGLING TO MIX THOSE TEMPS TO THE SURFACE. WILL GO WITH THE
MIDDLE GROUND SINCE IT IS SO FAR OUT...HIGHS IN THE MID-UPPER
40S...BUT IF WE CAN TAP INTO THE WARMER TEMPS ALOFT...COULD EASILY
SEE HIGHS IN THE 50S AT THE FIRST PART OF NEXT WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 713 PM EST MON NOV 12 2012
KIWD...CIGS MAY BRIEFLY DROP TO MVFR THIS EVENING AS WINDS TURN WRLY
BRINGING IN SOME LAKE CLOUDS...BUT EXPECT VFR CONDITIONS TO RETURN
AFT 06Z TONIGHT AS WINDS AGAIN BACK SW.
KCMX...DOMINANT LES BAND WHICH MOVED ONSHORE OVER THE KEWEENAW
PENINSULA LATE THIS AFTERNOON HAS NOW SAGGED SOUTH OF KCMX. LOOK FOR
IMPROVEMENT IN CONDITIONS FROM LIFR TO MVFR BY LATE EVENING WITH A
TRANSITION TO MORE WIND-PARALLEL MULTIBAND LES IN WRLY FLOW. LOWERING
SUBSIDENCE INVERSION WITH RIDGE BUILDING IN FM THE WEST SHOULD PUT AN
END TO SNOW LATE TONIGHT/EARLY TUE WITH IMPROVEMENT TO VFR CONDITIONS
TUE AFTERNOON AS WINDS BACK FM ONSHORE WRLY TO SWRLY.
KSAW...EXPECT VFR CONDITIONS THROUGH THE FCST PD AS WINDS SHIFT FROM
WSW TONIGHT TO SSW ON TUESDAY.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 405 PM EST MON NOV 12 2012
A TIGHT PRESSURE GRADIENT BETWEEN THE FRONT THAT MOVED THROUGH LAST
NIGHT AND ANOTHER SURFACE TROUGH MOVING THROUGH NORTHERN MN WILL
KEEP WINDS IN THE 20-30KT RANGE TONIGHT AS THEY SHIFT TO A MORE
NORTHWESTERLY DIRECTION. THERE COULD ALSO BE A FEW GALE FORCE GUSTS
TO 35 KNOTS TONIGHT...MAINLY OVER THE EASTERN HALF OF LAKE SUPERIOR.
A WEAK HIGH PRESSURE RIDGE WILL MOVE ACROSS LAKE SUPERIOR ON TUESDAY
NIGHT AND LEAD TO WINDS WEAKENING BELOW 25KTS. A LOW PRESSURE SYSTEM
MOVING INTO HUDSON BAY WILL BRING A TIGHTENING PRESSURE GRADIENT
OVER LAKE SUPERIOR...WHICH WILL INCREASE WINDS OUT OF THE SOUTHWEST
TO 20-30KTS OVER EASTERN LAKE SUPERIOR ON WEDNESDAY INTO WEDNESDAY
EVENING. HIGH PRESSURE WILL THEN SETUP OVER THE GREAT LAKES REGION
ON THURSDAY NIGHT AND SLOWLY DRIFT TO THE NORTHEAST THROUGH THE
FIRST PART OF NEXT WEEK. THIS WILL LEAD TO WINDS STAYING BELOW
20KTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL 7 AM EST TUESDAY FOR MIZ001>004-
084.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...VOSS
SHORT TERM...ROLFSON
LONG TERM...SRF
AVIATION...VOSS
MARINE...SRF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
715 PM EST MON NOV 12 2012
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 405 PM EST MON NOV 12 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A HIGH AMPLITUDE BUT
WEAKENING TROF EXTENDING FROM NRN ONTARIO THRU THE MISSISSIPPI
VALLEY. UNDERNEATH TROF EARLIER TODAY...12Z SOUNDINGS AT KINL/KMPX
SHOWED A DEEP MOISTURE PROFILE WITH 850MB TEMPS AROUND -15C WHICH
WILL ALLOW FOR A NICE INTERSECTION OF LAKE CONVECTION THRU THE DGZ.
SO...CONDITIONS ARE FAVORABLE FOR MDT/HVY LAKE EFFECT/LAKE ENHANCED
SNOW AS MID LEVEL TROF CONTINUES TO MOVE ACROSS THE UPPER GREAT
LAKES LATE THIS AFTN/EVENING. AS EXPECTED...A DOMINANT LES BAND
DEVELOPED OVER WRN LAKE SUPERIOR EARLIER TODAY BTWN THE MN NORTH
SHORE AND WISCONSIN`S BAYFIELD PENINSULA. WITH MID LEVEL TROF
PASSING...WINDS OVER WRN LAKE SUPERIOR ARE NOW VEERING MORE WRLY...
SO THIS DOMINANT LES BAND IS ADJUSTING TO THE CHANGING WIND...BUT IT
IS ALSO BECOMING LESS ORGANIZED...WHICH MAY BE PARTLY DUE TO
NEGATIVE DIURNAL AFFECTS. KMQT/KDLH AND ENVIRONMENT CANADA RADAR
LOCATED JUST N OF THUNDER BAY ALL INDICATE AREAS OF HEAVY LES NOW
NEARING THE WRN SHORE OF THE KEWEENAW. KDLH RADAR IS STILL SHOWING
RETURNS AS HIGH AS AROUND 12KFT...SO LAKE EFFECT CONVECTION REMAINS
DEEP WITH POCKETS OF VERY HVY SNOW. AHEAD OF THE HEAVIER SNOW...SHSN
HAVE BEEN AFFECTING PORTIONS OF THE KEWEENAW TODAY. HOWEVER...ONLY
WEBCAM THAT HAS CONSISTENTLY SHOWN SHARPLY REDUCED VIS AT TIMES IS
LOCATED ALONG THE SHORE WEST OF EAGLE RIVER.
FCST THINKING HASN`T CHANGED MUCH WITH REGARD TO LES AND HEADLINES
TONIGHT. DEEP MOISTURE AND FAVORABLE TEMP PROFILE ARGUES FOR MDT TO
HVY SNOW AT TIMES AS MID LEVEL TROF PASSES TONIGHT. BULK OF SNOW
ACCUMULATIONS ON THE KEWEENAW PENINSULA WILL OCCUR OVER THE NEXT
SEVERAL HRS AS WIND SHIFT/CONVERGENCE ZONE OVER THE WRN LAKE DROP S
ACROSS THE PENINSULA. MAY SEE SNOWFALL RATES BRIEFLY AS HIGH AS
2-4IN/HR. AFTER THE CONVERGENCE ZONE PASSES...WIND PARALLEL BANDS
WITH MUCH MORE VARIABLE SNOW INTENSITY WILL SET UP FOR THE REMAINDER
OF THE EVENING. LES WILL THEN QUICKLY DIMINISH OVERNIGHT AS SHARP
HEIGHT RISES OCCUR IN THE WAKE OF MID LEVEL TROF (180-200M HEIGHT
RISES AT 500MB BTWN 00Z AND 12Z)...INVERSION QUICKLY DROPS TO 4-5KFT
AND CONVECTIVE LAYER BEGINS TO FALL BLO THE DGZ. GIVEN THE SHORT
RESIDENCE TIME OF THE CONVERGENCE ZONE OVER THE KEWEENAW...AND
RATHER QUICK DIMINISHING TREND THRU THE NIGHT...HAVE LOWERED SNOW
AMOUNTS BY AN INCH OR TWO. MAX AMOUNTS WILL PROBABLY BE IN THE 4-5
INCH RANGE OVER THE HIGH TERRAIN.
FARTHER S...CONVERGENCE ZONE WILL SINK S AND AFFECT ONTONAGON/SRN
HOUGHTON COUNTIES THIS EVENING. ALTHOUGH PREVIOUSLY DISCUSSED
NEGATIVE FACTORS TAKE HOLD DURING THE NIGHT TO DIMINISH LES
INTENSITY...LOW-LEVEL WINDS WILL MAINTAIN A CONVERGENT LOOK AS WSW
LAND BREEZE ENHANCED WINDS OFF NW WI CONVERGE WITH WNW FLOW OVER
LAKE SUPERIOR. THIS SHOULD HELP TO AT LEAST MAINTAIN MORE PERSISTENT
THOUGH WEAKENING LES ACROSS ONTONAGON/SRN HOUGHTON COUNTIES AND
PROBABLY A SMALL PART OF GOGEBIC COUNTY N OF M-28 THRU THE NIGHT.
WILL RETAIN ADVY FOR ONTONAGON/SRN HOUGHTON COUNTIES TONIGHT.
TO THE E...WIND SHIFT/CONVERGENT BAND WILL EVENTUALLY MOVE ONSHORE
OVER THE NE FCST AREA TONIGHT. HOWEVER...BY THE TIME IT DOES...DEEP
MOISTURE WILL BE EXITING WITH SHARP HEIGHT RISES OCCURRING. SO...
WHILE THERE WILL LIKELY BE A BRIEF PERIOD OF MDT/HVY SNOW ON WIND
SHIFT...LES THAT ORGANIZES BEHIND TROF WILL NOT BE SUBSTANTIAL. WILL
PAINT 1-3 INCH ACCUMULATIONS ACROSS ALGER COUNTY E OF MUNISING AND
NRN LUCE COUNTY TONIGHT.
LINGERING LES WILL QUICKLY WIND DOWN/END FROM W TO E TUE. MIGHT SEE
AN ADDITIONAL INCH OF SNOW OVER ERN ALGER/NRN LUCE COUNTY IN THE
MORNING. OTHERWISE...LOOK FOR DECREASING CLOUDS FROM SW TO NE AS
WINDS BACK TO THE SW.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 405 PM EST MON NOV 12 2012
UPPER TROUGH THAT HAS LED TO THE UNSETTLED WEATHER THIS WEEKEND AND
TODAY WILL BE SHIFTING EAST OF THE UPPER GREAT LAKES ON TUESDAY
NIGHT. THIS WILL LEAD TO THE START OF SPLIT FLOW ACROSS MUCH OF THE
COUNTRY...WHICH WILL REALLY BECOME ESTABLISHED ON BY THE WEEKEND
BEHIND A WEAKER TROUGH MOVING THROUGH THE NORTHERN STREAM WEDNESDAY
INTO FRIDAY. THIS WILL LEAD TO A FAIRLY QUIET PATTERN ACROSS THE
UPPER GREAT LAKES FOR THE LONG TERM PERIOD.
HIGH PRESSURE RIDGE WILL BE OVER THE AREA AT THE START OF THE LONG
TERM PERIOD FROM HIGH PRESSURE CENTERED OVER THE LOWER GREAT LAKES
AND OHIO RIVER VALLEY. MOSTLY CLEAR SKIES TO START THE EVENING WILL
QUICKLY GIVE WAY TO INCREASING CLOUDS OVER THE WEST/CENTRAL...WHILE
ANY LINGERING LAKE EFFECT SHOWERS SHOULD BE PUSHING NE OVER EASTERN
LAKE SUPERIOR. THESE CLOUDS ARE IN ADVANCE OF A WEAK SHORTWAVE AND
WARM AIR ADVECTION THAT WILL MOVE ACROSS THE WESTERN CWA WEDNESDAY.
MODELS ARE CONSISTENT ON MOST OF THE MOISTURE STAYING ABOVE
H800...WITH BROAD AND WEAK LIFT ASSOCIATED WITH IT. THERE IS SOME
DRY AIR BELOW H800...BUT NOTHING TOO SUBSTANTIAL...SO THINK THAT
ANY PRECIPITATION THAT DOES FALL WILL MAKE IT TO THE SURFACE. WITH
THE BEST FORCING OVER WESTERN LAKE SUPERIOR...EXPECT THAT AREA TO
HAVE THE BEST CHANCE OF SHOWERS...SO HAVE SPREAD THE SLIGHT CHANCES
FARTHER SOUTH TO COVER MUCH OF WESTERN LAKE SUPERIOR ON WEDNESDAY.
OTHERWISE...THE MID CLOUDS WILL COVER THE REST OF THE CWA WITH ONLY
AN ISOLATED FLURRY OVER WESTERN UPPER MICHIGAN.
ONE OTHER ITEM OF NOTE FOR LATE TUESDAY NIGHT AND INTO WEDNESDAY
IS THE POTENTIAL FOR LAKE EFFECT PRECIPITATION OFF LAKE MICHIGAN.
DELTA T VALUES AROUND 15 WOULD SUPPORT LAKE ENHANCED PRECIPITATION
UNDER THE SLOWLY BACKING WINDS FROM SW TO SOUTHERLY ON WEDNESDAY.
MAIN LIMITING FACTOR APPEARS TO BE INVERSION HEIGHTS AROUND
4-5KFT. THERE ARE SOME HINTS IN THE MODELS THAT THIS INVERSION COULD
WEAKEN AS THE DEEPER MOISTURE ARRIVES AND LEAD TO AN INCREASE IN
INTENSITY. THIS LOOKS TO BE FAIRLY SHORT LIVED...AS DRIER
AIR BETWEEN H875-700 AND WAA MOVES BACK IN DURING THE AFTERNOON AND
DIMINISHES THE CHANCES AGAIN. WILL CONTINUE TO MENTION THE SLIGHT
CHANCES FOR THIS POTENTIAL...BUT SEEMS TO BE FAIRLY LIMITED.
THE SHORTWAVE MOVES AWAY FROM THE AREA WHILE A LOW PRESSURE SYSTEM
MOVES INTO HUDSON BAY. THIS SHOULD LEAD TO INCREASING SOUTHERLY
FLOW AHEAD OF A WEAK COLD FRONT MOVING INTO WESTERN ONTARIO. EXPECT
MID CLOUDS TO INCREASE AHEAD OF THIS FRONT ON WEDNESDAY
NIGHT...ESPECIALLY OVER THE NORTH HALF OF THE CWA. BOTH NAM/SREF
INDICATING INCREASED PROBABILITIES OF FOG OVER THE WEST...BUT THE
NAM HAS THINNER MID CLOUDS...WHICH WOULD LEAD BETTER RADIATIONAL
COOLING AND FOG POTENTIAL. WITH THE DIFFERENCES DIFFERENCES
IN THE MID CLOUDS...WILL LEAVE FOG MENTION OUT OF THE FORECAST DUE
TO THE POTENTIAL FOR MID CLOUDS.
DECAYING FRONTAL BOUNDARY WILL BE MOVING ACROSS THE NORTHERN HALF OF
THE CWA ON THURSDAY. THIS WILL LARGELY BE MARKED BY A WIND SHIFT AND
CLOUDS WHILE THE PRECIPITATION WILL STAY TO THE NORTH OF LAKE
SUPERIOR AND CLOSER TO THE BETTER FORCING/MOISTURE.
BEHIND THIS FRONTAL BOUNDARY AND WEAK UPPER TROUGH...SPLIT FLOW
REALLY SETTLES OVER THE NORTHERN HALF OF THE CONUS. THE SOUTHERN
STREAM JET LOOKS TO REMAIN OVER THE SOUTHERN TIER OF STATES...WHILE
THE NORTHERN STREAM RIDGES OVER NORTHERN CANADA. THIS SHOULD LEAD TO
A VERY QUIET AND LIKELY ABOVE NORMAL TEMPERATURE PERIOD FOR UPPER
MICHIGAN INTO NEXT WEEK. AT THE SURFACE...HIGH PRESSURE WILL SETTLE
OVER THE GREAT LAKES REGION FOR THURSDAY NIGHT INTO SATURDAY BEFORE
MOVING EAST INTO QUEBEC FOR SUNDAY AND MONDAY. DRY AIR ASSOCIATED
WITH THIS HIGH SHOULD PRODUCE DECREASING CLOUDS ON THURSDAY NIGHT
AND FRIDAY AND THEN PARTLY CLOUDY TO MOSTLY CLEAR SKIES INTO NEXT
WEEK. BIGGEST QUESTION WILL BE THE TEMPERATURES...AS THEY WILL
DEPEND ON HOW DEEP THE MIXING WILL BE. BOTH GFS/ECMWF INDICATING
H850 TEMPS RISING TOWARDS 1-2C THIS WEEKEND...BUT BOTH ARE
STRUGGLING TO MIX THOSE TEMPS TO THE SURFACE. WILL GO WITH THE
MIDDLE GROUND SINCE IT IS SO FAR OUT...HIGHS IN THE MID-UPPER
40S...BUT IF WE CAN TAP INTO THE WARMER TEMPS ALOFT...COULD EASILY
SEE HIGHS IN THE 50S AT THE FIRST PART OF NEXT WEEK.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 713 PM EST MON NOV 12 2012
KIWD...CIGS MAY BRIEFLY DROP TO MVFR THIS EVENING AS WINDS TURN WRLY
BRINGING IN SOME LAKE CLOUDS...BUT EXPECT VFR CONDITIONS TO RETURN
AFT 06Z TONIGHT AS WINDS AGAIN BACK SW.
KCMX...DOMINANT LES BAND WHICH MOVED ONSHORE OVER THE KEWEENAW
PENINSULA LATE THIS AFTERNOON HAS NOW SAGGED SOUTH OF KCMX. LOOK FOR
IMPROVEMENT IN CONDITIONS FROM LIFR TO MVFR BY LATE EVENING WITH A
TRANSITION TO MORE WIND-PARALLEL MULTIBAND LES IN WRLY FLOW. LOWERING
SUBSIDENCE INVERSION WITH RIDGE BUILDING IN FM THE WEST SHOULD PUT AN
END TO SNOW LATE TONIGHT/EARLY TUE WITH IMPROVEMENT TO VFR CONDITIONS
TUE AFTERNOON AS WINDS BACK FM ONSHORE WRLY TO SWRLY.
KSAW...EXPECT VFR CONDITIONS THROUGH THE FCST PD AS WINDS SHIFT FROM
WSW TONIGHT TO SSW ON TUESDAY.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 405 PM EST MON NOV 12 2012
A TIGHT PRESSURE GRADIENT BETWEEN THE FRONT THAT MOVED THROUGH LAST
NIGHT AND ANOTHER SURFACE TROUGH MOVING THROUGH NORTHERN MN WILL
KEEP WINDS IN THE 20-30KT RANGE TONIGHT AS THEY SHIFT TO A MORE
NORTHWESTERLY DIRECTION. THERE COULD ALSO BE A FEW GALE FORCE GUSTS
TO 35 KNOTS TONIGHT...MAINLY OVER THE EASTERN HALF OF LAKE SUPERIOR.
A WEAK HIGH PRESSURE RIDGE WILL MOVE ACROSS LAKE SUPERIOR ON TUESDAY
NIGHT AND LEAD TO WINDS WEAKENING BELOW 25KTS. A LOW PRESSURE SYSTEM
MOVING INTO HUDSON BAY WILL BRING A TIGHTENING PRESSURE GRADIENT
OVER LAKE SUPERIOR...WHICH WILL INCREASE WINDS OUT OF THE SOUTHWEST
TO 20-30KTS OVER EASTERN LAKE SUPERIOR ON WEDNESDAY INTO WEDNESDAY
EVENING. HIGH PRESSURE WILL THEN SETUP OVER THE GREAT LAKES REGION
ON THURSDAY NIGHT AND SLOWLY DRIFT TO THE NORTHEAST THROUGH THE
FIRST PART OF NEXT WEEK. THIS WILL LEAD TO WINDS STAYING BELOW
20KTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL 7 AM EST TUESDAY FOR MIZ001>003-
084.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...SRF
AVIATION...VOSS
MARINE...SRF
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
619 PM EST MON NOV 12 2012
.SYNOPSIS...
ISSUED AT 330 PM EST MON NOV 12 2012
SNOW SHOWERS WILL INCREASE TONIGHT WITH SOME LIGHT ACCUMULATIONS
OF AN INCH OR LESS POSSIBLE. SOME SLIPPERY SPOTS MAY DEVELOP ON
ROADS BY THIS EVENING BUT IMPACT TO TRAVEL SHOULD BE MINIMAL IN
MOST PLACES. THE SNOW SHOWERS WILL END ON TUESDAY WITH FAIR AND
COOL WEATHER FOR THE REST OF THE WEEK.
&&
.SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT)
ISSUED AT 330 PM EST MON NOV 12 2012
MAIN FORECAST ISSUE IS FOR POPS TONIGHT AND TUESDAY AS CYCLONIC
FLOW AND SOME LAKE ENHANCED SNOW SHOWERS ARE EXPECTED. IT WOULD
SEEM THE SNOW WILL BE LIGHT ENOUGH TO RESULT IN LITTLE IF ANY
IMPACT TO TRAVEL UNTIL LATER THIS EVENING...WHEN SOME SLIPPERY
SPOTS ARE POSSIBLE.
AIR TEMPS WILL CONTINUE TO FALL BELOW FREEZING...WITH SKIN TEMPS
DROPPING TO NEAR OR BELOW FREEZING BY MIDNIGHT. VORT MAX AND
ASSOCIATED SNOW SHOWERS CURRENTLY SEEN ACROSS WISCONSIN WILL
TRANSLATE EAST AND GET A BOOST FROM LAKE MICHIGAN. WENT WITH
LIKELY POPS ACROSS THE NORTHERN FORECAST AREA WHERE LIFT AND
MOISTURE WILL BE GREATEST. WENT FAR ABOVE GUIDANCE POPS ACROSS ALL
ZONES...BUT HELD OFF ON AN ADVISORY SINCE SNOW IS NOT EXPECTED TO
CAUSE MORE THAN PATCHY SLICK SPOTS ON AREA ROADS.
THE VORT MAX MOVES EASY BY TUESDAY MORNING BUT A WEAK SHORTWAVE
TROUGH AXIS AND RESIDUAL MOISTURE COULD KEEP SCATTERED SNOW
SHOWERS GOING THROUGH THE MORNING BEFORE UPPER AND SFC RIDGING
PUTS AN END TO THEM BY TUESDAY AFTERNOON.
&&
.LONG TERM...(THURSDAY THROUGH MONDAY)
ISSUED AT 330 PM EST MON NOV 12 2012
FORECAST CONCERNS IN THE LONG TERM PORTION OF THE FCST ARE RATHER
MINIMAL...ESPECIALLY CONSIDERING THAT WE ARE IN THE MIDDLE OF
NOVEMBER. PCPN CHCS LOOK QUITE LIMITED...SO CLOUD AND TEMPERATURE
TRENDS ARE THE MAIN FOCUS.
WE ARE STILL EXPECTING ONE SYSTEM TO DROP SE THROUGH THE AREA DURING
THE DAY ON THU. THIS IS A DECENT UPPER TROUGH...HOWEVER IT DOES NOT
LOOK TO HAVE MUCH MOISTURE BELOW 10-15K FT. THIS OCCURS AS A DRY
ERLY FLOW WILL BE IN PLACE AHEAD OF THE SYSTEM. THE SYSTEM WILL NOT
HAVE A INFLUX OF MOISTURE AS THE GULF OF MEXICO IS SHUT OFF AND THE
ROCKIES WILL HELP TO DRY UP THE MOISTURE AS THE SYSTEM MOVES IN FROM
THE WEST.
THE REMAINDER OF THE FCST PERIOD THROUGH NEXT MON /AND EVEN BEYOND
THAT/ LOOKS TO BE RATHER DRY AND SEASONABLE. WE WILL SEE THE THU
TROUGH CLOSE OFF OVER THE SE STATES. THIS WILL SLOW UP THE SRN
BRANCH OF THE JET. THE NRN BRANCH WILL REMAIN WELL NORTH INTO
CANADA. THIS WILL LEAVE THE REGION IN BETWEEN THE JET BRANCHES AND
UNDER THE INFLUENCE OF HIGH PRESSURE TO THE NE WHICH WILL FEED IN
DRIER AND SEASONABLE AIR FROM THE EAST. HIGHS SHOULD RANGE FROM THE
MID 40S TO LOWER 50S. LOWS WILL BE IN THE MID 20S TO MID 30S THROUGH
THE PERIOD.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING)
ISSUED AT 619 PM EST MON NOV 12 2012
I EXPECT A PERIOD OF SNOW SHOWERS WITH VSBY INTERMITTENTLY BELOW 3
MILES... LOCALLY NEAR 1 MILE BETWEEN 03Z AND 06Z. IMPROVEMENT WILL
FOLLOW SLOWLY AFTER THAT.
SNOW SHOWERS ARE DEVELOPING BOTH ON OUR RADAR AND IN THE SURFACE
OBSERVATIONS. AS OF 23Z MOST OF THE LAKE SHORE STATIONS NORTH OF
MKG...LIKE MBL...TVC...FKS...CVX ALL REPORT VSBY AROUND 2 MILES IN
SNOW SHOWERS. THE LATEST RUNS OF THE HRRR RUC AND THE RAP-
DEV1-ESRL SHOW THE BEST COVERAGE AS THE COLDEST POOL OF AIR AT MID
LEVELS MOVES ACROSS THE AREA (03Z-06Z). IT IS AT THAT TIME THE
INVERSION HEIGHTS ARE THE HEIGHTS. SATELLITE LOOPS SHOW THE
COLDEST COLD TOPS STILL OVER WI INTO CNTL LAKE MICHIGAN. ALL OF
THIS SUGGESTS THE 03Z-06Z TIME FRAME IS WHEN WE SHOULD EXPECT THE
STRONGEST SNOW SHOWERS. OCNL IFR VSBY SHOULD BE EXPECTED AT THE
GRR AZO AND BTL TAF SITES. MKG IS TO CLOSE TO THE LAKE SO THEY
SHOULD NOT HAVE AS LOW OF VSBY WITH THE SNOW SHOWERS.
ALL OF THIS MOVES OUT AFTER 06Z AS THE COLDEST AIR ALSO BEGINS TO
MOVE EAST OF THE AREA. THE SNOW SHOWERS SHOULD TOTALLY COME TO AN
END BY MID MORNING TUESDAY. GRADUAL CLEARING WILL THEN FOLLOW. I
EXPECT VFR CIGS AFTER 12Z ACROSS ALL OF OUR TAF SITES.
&&
.MARINE...
ISSUED AT 318 PM EST MON NOV 12 2012
WINDS AND WAVES WILL SLOWLY SUBSIDE OVERNIGHT AND ARE STILL
EXPECTED TO FALL BELOW SCA CRITERIA BY LATE TUESDAY MORNING. MADE
NO CHANGES TO THE HEADLINES.
&&
.HYDROLOGY...
ISSUED AT 318 PM EST MON NOV 12 2012
NO HYDRO ISSUES.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 10 AM EST TUESDAY FOR LMZ844>849.
&&
$$
SYNOPSIS...OSTUNO
SHORT TERM...OSTUNO
LONG TERM...NJJ
AVIATION...WDM
HYDROLOGY...OSTUNO
MARINE...OSTUNO
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
445 PM EST SUN NOV 11 2012
.SHORT TERM...(THIS EVENING THROUGH MONDAY)
ISSUED AT 442 PM EST SUN NOV 11 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A DEEP TROF EXTENDING FROM
SCNTRL CANADA THRU THE WRN PLAINS. DEEP SRLY FLOW THAT HAS BEEN
OCCURRING AHEAD OF THE TROF HAS TRANSPORTED ABUNDANT MOISTURE N INTO
THE WRN GREAT LAKES. 12Z RAOBS SHOW PRECIPITABLE WATER RUNNING
200-275PCT OF NORMAL OVER THE WRN GREAT LAKES. AT THE SFC...SHARP
COLD FRONT EXTENDS FROM CNTRL LAKE SUPERIOR TO JUST E OF THE
KEWEENAW AND THEN S TO THE W OF KIMT. SHARP FRONT PLOWING INTO DEEP
MOISTURE COMBINED WITH HEALTHY UPPER DIVERGENCE ASSOCIATED WITH
130-140KT UPPER JET STREAK LIFTING UP FRONT SIDE OF TROF HAS
RESULTED IN A SOLID BAND OF SHRA ALONG THE COLD FRONT TODAY. BEHIND
THE FRONT...TEMP HAS ALREADY PLUMMETED TO 37 AT KIWD WHERE RAIN IS
JUST ABOUT DONE.
THERE ARE PLENTY OF CONCERNS IN THE SHORT TERM...RANGING FROM
PROGRESSION OF RAIN BAND E ACROSS THE AREA TONIGHT...POSSIBLE BRIEF
WINTRY MIX ON THE BACKSIDE OF THE RAIN...AND THEN TRANSITION TO LES
AND POSSIBLE WINTER WX HEADLINE MON.
FCST FOR THIS EVENING IS LARGELY BASED ON EXTRAPOLATION OF SHRA.
SINCE UPPER DIVERGENCE OVERTOP SHARP COLD FRONT WILL ALLOW SHRA TO
PERSIST ALONG FRONT AS IT MOVES E...WILL SPREAD CATEGORICAL POPS
STEADILY E ACROSS THE CNTRL AND ERN FCST AREA TONIGHT IN ASSOCIATION
WITH SFC COLD FRONT WHICH SHOULD REACH THE SOO LATE TONIGHT. PCPN
ACROSS THE W AND CNTRL WILL END AS RIBBON OF PRONOUNCED MIDLEVEL
DRYING FOLLOWS UPPER JET STREAK TRANSLATING ACROSS THE AREA. BEFORE
PCPN ENDS...THERE IS A SMALL WINDOW FOR A LITTLE SLEET THEN SNOW TO
OCCUR AS INITIALLY SHALLOW COLD AIR UNDERCUTS THE LINGERING WARMER
AIR ALOFT. HOWEVER...THERE ISN`T MUCH SIGNAL FOR SUFFICIENT FORCING
TOO FAR W OF THE COLD FRONT TO COUNTER THE SHARP MID LEVEL DRYING
AND KEEP PCPN LINGERING IN THE COLD AIR FOR TOO LONG. ANY SLEET OR
SNOW THAT DOES OCCUR ON THE BACKSIDE OF THE MAIN FRONTAL SHRA BAND
SHOULDN`T AMOUNT TO MUCH IF ANYTHING. THE MIXED PCPN POTENTIAL WILL
SPREAD INTO THE ERN FCST AREA LATE TONIGHT AS MODELS ARE A LITTLE
FASTER WITH CAA. LINGERING LIGHT PCPN OVER THE E SHOULD END BY MID
MORNING MON.
AS MAIN SYNOPTIC PCPN EXITS...ATTENTION TURNS TO LAKE EFFECT SNOW.
WITH SFC WATER TEMPS OVER WRN LAKE SUPERIOR AROUND 6C...MODEL
CONSENSUS IS FOR 850MB TEMPS TO FALL SUFFICIENTLY FOR LES
DEVELOPMENT AFTER 06Z...BUT MORE SO BTWN 09-12Z AS TEMPS WILL BE
DOWN TO -12 TO -14C AT 12Z. MIDLEVEL DRY SLOT WILL INITIALLY WORK TO
KEEP COVERAGE MORE LIMITED. SO SCT COVERAGE POPS FOR -SHSN APPEAR ON
TRACK FOR THE OVERNIGHT.
LES FCST GETS MORE INTERESTING MON AS MID LEVEL TROF AXIS AND POOL
OF DEEP MOISTURE ARRIVES. THIS RESULTS IN INVERSION LIFTING TOWARD
10KFT. WITH 850MB TEMPS AVERAGING AROUND -13C THRU THE DAY...DGZ
ENDS UP WITHIN THE MOIST CONVECTIVE LAYER...AND AT LEAST WITH THE
NAM...THERE IS A NICE INTERSECTION OF UPWARD MOTION THRU THE DGZ.
WIND DIRECTION WILL BE CRITICAL. VARIOUS HIGH RES MODELS (LOCAL HIGH
RES WRF AND NCEP HIGH RES ARW/NMM) INCLUDING NAM/REGIONAL GEM ARE IN
GOOD AGREEMENT SHOWING MORE OF A WSW WIND OVER WRN LAKE SUPERIOR AND
ARE SUGGESTIVE OF A DOMINANT CONVERGENT BAND DEVELOPING NEAR THE
APOSTLE ISLANDS AND STREAMING TOWARD THE NRN PORTION OF THE KEWEENAW
PENINSULA MON...WHICH IS A COMMON OCCURRENCE FOR THIS TYPE OF
LOW-LEVEL WIND FLOW. GIVEN THE AGREEMENT...HAVE FOLLOWED THIS
SCENARIO. WITH POTENTIAL OF MDT TO PERHAPS HVY LAKE ENHANCED SNOW AT
TIMES GIVEN FAVORABLE TEMP/MOISTURE PROFILE...OPTED TO GO WITH A
WINTER WX ADVY FOR NRN HOUGHTON/KEWEENAW COUNTIES MON. EXPECT MAIN
FOCUS OF HEAVIER LES TO BE N OF HOUGHTON...PARTICULARLY IN THE AFTN
OVER THE HIGHER TERRAIN FROM AROUND CALUMET THRU DELAWARE WHERE SNOW
MAY ACCUMULATE TO AROUND 4 INCHES DURING THE DAY MON. VERY LATE IN THE
AFTN...WINDS WILL BEGIN TO SHIFT MORE TO THE W WHICH WILL PUSH
HEAVIER SNOW OVER MORE OF THE KEWEENAW PENINSULA. SINCE ONTONAGON
COUNTY WILL BE SOUTH OF THE HEAVIER SNOW AND POSSIBLY S OF MOST OF
THE LAKE ENHANCED SNOW...DID NOT INCLUDE ADVY FOR THAT AREA AT THIS
TIME. TO THE E...WINDS WILL PROBABLY HAVE ENOUGH OFFSHORE COMPONENT
TO KEEP MOST OF THE DEVELOPING LAKE ENHANCED SNOW OFFSHORE OF
ALGER/LUCE COUNTIES. ELSEWHERE...EXPECT SCT FLURRIES/-SHSN TO
ACCOMPANY ARRIVAL OF MIDLEVEL TROF OVER ROUGHLY THE W HALF OF UPPER
MI MON. WITH 850MB THERMAL TROF MOVING OVER THE AREA...TEMPS SHOULD
RISE VERY LITTLE. IN FACT...TO THE W...TEMPS THIS AFTN ARE ONLY IN
THE UPPER TEENS/LWR 20S IN THE ERN DAKOTAS/WRN MN. SO...TEMPS LIKELY
WON`T RISE OUT OF THE MID/UPPER 20S OVER WRN UPPER MI MON...AND
TEMPS MAY FALL SOME OVER THE E AS CAA CONTINUES THRU THE MORNING IN
THAT AREA.
.LONG TERM...(MONDAY NIGHT THROUGH SUNDAY)
ISSUED AT 442 PM EST SUN NOV 11 2012
NOT MUCH CHANGE TO PREVIOUS FORECAST THINKING IN THE LONG TERM WITH
MAIN FOCUS MON NIGHT INTO TUE WITH LES.
A SHARP UPPER TROUGH WILL BE OVER THE CENTRAL CWA /E OF THE
KEWEENAW/ AT 00Z TUE WITH A SLIGHTLY LAGGING SFC TROUGH OVER WRN
LAKE SUPERIOR. COLD AIR ASSOCIATED WITH THIS TROUGH CAUSES CONCERN
WITH CHANCES FOR LES PARTICULARLY OVER THE KEWEENAW PENINSULA. 850MB
TEMPS WILL BE AROUND -11C AT 00Z TUE...WITH THE TOP OF THE INVERSION
ABOVE THE DGZ AT AROUND 9500FT WITH TEMPS AROUND -24C. WHILE 850MB
TEMPS WILL BE A COUPLE OF DEGREES WARMER THAT A FEW HOURS
BEFORE...THE INVERSION LOOKS TO BE DEEPEST AROUND 00Z TUE...SO BEST
OVERALL AVG COVERAGE/INTENSITY SHOULD BE SEEN AROUND THIS TIME.
AFTER 00Z TUE...A SFC RIDGE WILL MOVE OVERHEAD BY 18Z TUE WITH 850MB
TEMPS STEADILY INCREASING TO AOA -5C BY 00Z WED. MOISTURE...WHICH
WILL BE AMPLE FOR LES AT 00Z...WILL DECREASE AFTER 00Z TUE. MOISTURE
FROM 850MB AND UP WILL DECREASE TO BELOW 60 PERCENT RH OVER THE WRN
HALF OF LAKE SUPERIOR BY 09Z TUE...AND OVER THE ENTIRE LAKE BY 15Z
TUE. 925MB-850MB RH DECREASES BELOW 60 PERCENT OVER THE WRN HALF OF
LAKE SUPERIOR BY 15Z TUE...AND THE MOST OF THE REST OF THE LAKE BY
00Z WED. AT LEAST FROM 00Z TUE TO 06Z WED...WINDS LOOK TO GUST TO
35-40MPH OVER THE KEWEENAW PENINSULA WITH THE W WINDS. COLD SECTOR
LIVING AT ITS BEST.
TAKING A CLOSER LOOKS AT SNOWFALL AMOUNTS AND OTHER HAZARDS FOR TUE
NIGHT...LOW LEVEL WINDS WILL BE FAIRLY UNIDIRECTIONAL...WHICH IS
GOOD FOR LES BANDING. HOWEVER...WINDS WILL BE SHIFTING FROM A WSW
DIRECTION MON EVENING...WHICH WILL FAVOR A DOMINANT BAND WITH
INTENSE SNOWFALL AMOUNTS LATE MON. THOSE WSW WINDS BECOME MORE WLY
BY 00Z TUE AND SLOWLY VEER INTO TUE AS THE RIDGE MOVES IN FROM THE
W. THIS WILL MOVE THE WEAKENING DOMINANT BAND FROM N TO S ACROSS THE
KEWEENAW AND INTO ONTONAGON COUNTY MON NIGHT...BUT THE FACT THAT
WINDS WILL STEADILY VEER WILL KEEP THE STRONGER BAND FROM SITTING
OVER ANY ONE PLACE FOR TOO LONG...HELPING TO KEEP SNOWFALL TOTALS
FROM GETTING TO HIGH. THE BEST AREA OF LIFT WILL SPAN THE
DGZ...WHICH WILL HELP MAKE SNOW TO LIQUID RATIOS HIGH...BUT GUSTY
WINDS WILL KNOCK THOSE DOWN SOME. EXPECT SLR VALUES AROUND 18-20 TO
1. ADDITIONAL SNOWFALL AMOUNTS MON NIGHT /ON TOP OF WHAT FALL MON/
LOOK TO BE UP TO AROUND 4 INCHES...HIGHEST OVER THE HIGHER TERRAIN
FROM ROCKLAND TO SOUTH RANGE. WITH THE WINDS...BLOWING SNOW WILL
ALSO BE AN ISSUE...BUT A LIMITED ONE GIVEN NO SNOW ON THE GROUND
YET. AS FOR THE TUE MORNING COMMUTE OVER THE KEWEENAW...BY 12Z TUE
WINDS WILL HAVE DIMINISHED TO 20MPH OR LESS AND SNOWFALL RATES
SHOULD BE GREATLY REDUCED...SO CONDITIONS WILL MAINLY DEPEND ON HOW
WELL ROAD CREWS CAN CLEAR EARLIER SNOW OFF THE ROADS...BUT AT LEAST
SLICK ROADS APPEAR LIKELY.
WITH THE WINDS BECOMING MORE WNW THROUGH THE NIGHT...THE ERN CWA
NEAR LAKE SUPERIOR /MAINLY E OF MUNISING/ SHOULD SEE SOME MODERATE
TO HEAVY SNOWFALL AS WELL. THE FORECAST IS A BIT TRICKIER OVER
THERE...MAINLY DUE TO UNCERTAINTY WITH WHEN AND HOW FAR LES BAND
WILL MOVE ONSHORE. SIMILAR TO THE KEWEENAW THERE SHOULD BE A MORE
DOMINANT BAND SITTING OVER ERN LAKE SUPERIOR THAT WILL PUSH ONSHORE
AS CONDITIONS START TO BECOME LESS FAVORABLE FOR LES. PUSH
CONDITIONS BACK A FEW HOURS FROM TIMING OVER THE KEWEENAW...SO THE
BAND SHOULD BEGIN TO VEER ONSHORE AROUND 06Z TUE...BUT SHOULD BEGIN
WEAKENING SHORTLY DUE TO DRIER AIR AND MORE ANTICYCLONIC FLOW
GRADUALLY MOVING IN. COULD SEE TOTAL SNOWFALL AMOUNTS OF 3-4 INCHES
MON NIGHT INTO TUE.
HAVE A WINTER WX ADV THAT EXTENDS TO 12Z TUE FOR NRN HOUGHTON AND
KEWEENAW COUNTIES. WILL POSSIBLY NEED AN ADV FOR ONTONAGON AND MAYBE
SOUTHERN HOUGHTON COUNTY MON NIGHT...BUT WILL LEAVE THOSE DETAILS TO
MIDNIGHT SHIFT AND HIGHLIGHT IN HWO. ALSO MAY NEED AN ADV FOR PARTS
OF THE ERN CWA CLOSE TO LAKE SUPERIOR...BUT THOSE DETAILS ARE EVEN
LESS CERTAIN.
WITH FAIRLY BENIGN...LOW IMPACT WEATHER AFTER CONDITIONS SUBSIDE
TUE...JUST USED A CONSENSUS OF THE MODELS FOR THE REST OF THE
FORECAST SO AS TO PLACE MOST TIME/EMPHASIS ON SHORTER TERM IMPACTS.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1256 PM EST SUN NOV 11 2012
CONDITIONS WILL CONTINUE TO DETERIORATE AS SHRA OVERSPREADS WESTERN
AND CENTRAL UPPER MI IN RELATION TO A DISTURBANCE RIDING NEWD ALONG
COLD FRONT...CURRENTLY OVER FAR WESTERN UPPER MI. KEPT TAF SITES
WITHIN FUEL ALTERNATE CATEGORIES THROUGH THIS EVENING...THOUGH AS
MENTIONED BY PREVIOUS FORECAST...LIFR CONDITIONS CAN NOT BE RULED
OUT AT SOME POINT...ESPECIALLY AT CMX THIS AFTN/EVNG WITH GUSTY
UPSLOPE W WIND BEHIND THE COLD FROPA. EXPECT THE ARRIVAL OF DRIER
AIR TO CAUSE THE PCPN TO DIMINISH JUST AS ENUF COLD AIR SURGES INTO
THE AREA TO CHANGE THE RA TO SN. THE BEST CHC FOR HEAVIER -SHSN
LATER TNGT WL BE AT THE MORE EXPOSED CMX LOCATION...WHERE GUSTY
WINDS WL LINGER AS WELL. OTHERWISE...DRY AIR WILL CONTINUE TO
IMPROVE CIG CONDITIONS TO VFR AT KIWD AND KSAW BY MONDAY MORNING.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 442 PM EST SUN NOV 11 2012
SHARP COLD FRONT IS IN THE PROCESS OF CROSSING LAKE SUPERIOR ATTM.
AHEAD OF THE FRONT...S WINDS OVER ERN LAKE SUPERIOR WILL GUST TO
GALE FORCE AT TIMES THIS EVENING...ESPECIALLY IN THE AREA AROUND
GRAND MARAIS WHICH IS FAVORED FOR STRONG WINDS IN SOUTHERLY FLOW.
ALTHOUGH CAA IS STRONG BEHIND COLD FRONT...LACK OF STRONGER SFC PRES
RISES WILL PROBABLY RESULT IN WESTERLY WINDS REMAINING BLO GALE
FORCE TONIGHT. PRESSURE GRADIENT TIGHTENS JUST A BIT ON MON AS
SECONDARY SFC TROF APPROACHES. WITH COLD AIR AND UNSTABLE
LOW-LEVELS...OCNL GALE FORCE GUSTS TO 35KT ARE POSSIBLE MON/MON
EVENING. PRESSURE GRADIENT THEN SLACKENS LATE MON NIGHT/TUE WITH
WINDS DIMINISHING BLO 25 KTS. A LOW PRES TROF WILL PUSH ACROSS
NORTHERN ONTARIO THU. S WINDS AHEAD OF THE TROF COULD REACH 25 KTS
OVER EASTERN SECTIONS OF LAKE SUPERIOR WED/WED NIGHT. WINDS TO
FINISH UP THE WEEK WILL BE BLO 20 KTS AS PRESSURE GRADIENT BECOMES
WEAK WITH SFC HIGH PRES PASSING.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY FROM 7 AM MONDAY TO 7 AM EST TUESDAY FOR
MIZ001-003.
LAKE SUPERIOR...NONE.
LAKE MICHIGAN...
GALE WARNING UNTIL 10 PM EST THIS EVENING FOR LMZ248-250.
&&
$$
SHORT TERM...ROLFSON
LONG TERM...TITUS
AVIATION...JMW
MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1258 PM EST SUN NOV 11 2012
LATEST UPDATE...AVIATION...
.SYNOPSIS...
ISSUED AT 328 AM EST SUN NOV 11 2012
STRONG SOUTH WINDS WILL DEVELOP ACROSS THE REGION TODAY AHEAD OF A
STRONG COLD FRONT. A PUSH OF WARM AIR WILL SEND TEMPERATURES INTO
THE UPPER 60S A MANY LOCATIONS THIS AFTERNOON. SHOWERS WILL DEVELOP
LATE IN THE DAY AND CONTINUE TONIGHT AS THE FRONT MOVES ACROSS THE
AREA. MUCH COLDER AIR ALONG WITH RAIN AND SNOW SHOWERS WILL MOVE
INTO WEST MICHIGAN MONDAY. HIGH TEMPERATURES WILL SLOWLY FALL DURING
THE DAY AND ONLY REACH AROUND 40 DEGREES TUESDAY. MAINLY DRY WEATHER
IS EXPECTED AFTER MONDAY WITH SLOWLY WARMING TEMPERATURES.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 328 AM EST SUN NOV 11 2012
FORECAST CONCERNS DEAL WITH THE WIND POTENTIAL TODAY AND PCPN TRENDS
TONIGHT/MONDAY.
THE GOING FORECAST IS LARGELY ON TRACK. HOWEVER...WINDS APPEAR A BIT
STRONGER ACROSS THE WRN CWA AS THE GRADIENT TIGHTENS AHEAD OF THE
COLD FRONT. AS SUCH WE ISSUED A WIND ADVISORY FOR THE WRN 1/2 OF THE
CWA. WINDS ARE ALREADY GUSTING TO 36 KITS AT KMKG AND WILL LIKELY
INCREASE A BIT MORE AS THE SUN RISES AND BETTER MIXING OCCURS.
STRONG 65KT LLJ MOVES OVER THE WRN CWA LATE THIS AFTERNOON.
LATEST HRRR HAS A PRETTY GOOD HANDLE ON THE SHOWERS MOVING ACROSS
NRN IL/WISCONSIN. THESE ARE AHEAD OF THE COLD FRONT AND DISSIPATE
SOMEWHAT AS THEY MOVE EWD THIS AFTERNOON. AS A RESULT...WE
ANTICIPATE A DRY DAY. ABUNDANT MID CLOUD WILL BE PRESENT AND THIS
WILL LIMIT MIXING A BIT BUT NOT ENOUGH TO PREVENT SUSTAINED 25 TO 30
MPH WINDS. FROPA IS ON TRACK FOR MIDNIGHT-4AM TIME FRAME. TEMPS WILL
SLOWLY FALL MONDAY AS H8 TEMPS FALL TO -12C. RAIN WILL MIX WITH SNOW
AFTER FROPA THEN BECOME SHSN AS THE THERMAL PROFILE QUICKLY FALLS
BELOW 0C. NOT LOOKING FOR ACCUMS AT THIS POINT. THOUGH IT/S POSSIBLE
A FEW HIGHER ELEVATIONS ACROSS THE NRN CWA COULD SEE A COUPLE OF
TENTHS.
TUESDAY LOOKS DRY BUT CHILLY WITH HIGHS AROUND 40.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 328 AM EST SUN NOV 11 2012
FOR THE EXTENDED PERIOD...THE CORE OF THE ARCTIC AIR REMAINS WELL
NORTH OF THE REGION. ONE OF THE MAIN REASONS FOR THIS IS THE ZONAL
MID LEVEL FLOW THAT SETS UP ACROSS NORTH AMERICA FOR THE PERIOD.
HERE IN MI...WE WILL SEE ONLY A WEAKENING COLD FRONT ARRIVING THU.
IF THERE IS ANY PRECIPITATION WITH THIS SHALLOW FEATURE...IT WILL BE
LIMITED AS VERY LITTLE MOISTURE AND LIFT WILL BE IN PLACE.
TEMPERATURES AT 850 MB CLIMB THU INTO SAT...SO WE WILL LIKELY SEE A
GENERAL WARMING TREND. ALTHOUGH...GIVEN THE MID LEVEL
FLOW...PACIFIC MOISTURE COULD CAUSE PERIODS OF CLOUDS THAT WOULD
POTENTIALLY LIMIT THE DAYTIME MIXING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY)
ISSUED AT 1258 PM EST SUN NOV 11 2012
STRONG SOUTH FLOW AHEAD OF A COLD FRONT WILL RESULT IN GUSTS OVER 25
KNOTS FOR ALL TAF SITES INTO THE EVENING. WINDS WILL DECREASE A BIT
OVERNIGHT... BUT WILL PICK UP OUT OF THE WEST BEHIND THE FRONT.
EXPECTING CEILINGS TO FALL TO AROUND 2500 FEET TONIGHT WITH
VISIBILITIES MOSTLY ABOVE 3SM. ISOLATED IFR LEVELS MAY BE
EXPERIENCED UNDER THE STRONGEST CELLS. FEEL LOW CHANCE AT TAF SITES
FOR IFR OVERNIGHT... SO DID NOT INCLUDE. WENT WITH VCSH FOR MONDAY.
THE TEMPERATURES WILL BE FALLING... SO RAIN SHOWERS WILL TRANSITION
TO SNOW SHOWERS.
&&
.MARINE...
ISSUED AT 328 AM EST SUN NOV 11 2012
GIVEN THAT WINDS ALONG THE LAKESHORE ARE ALREADY GUSTING NEAR
35KTS...DECIDED TO RUN WITH THE GALE WARNING NOW AND DISCONTINUE THE
SCA. GALES TO 40KTS EXPECTED TODAY WILL BUILD WAVES TO 5 TO 8 FEET.
&&
.HYDROLOGY...
ISSUED AT 328 AM EST SUN NOV 11 2012
A THIRD OF AN INCH OF PCPN IS EXPECTED AHEAD OF THE COLD FRONT
TONIGHT. THIS SHOULDN/T RESULT IN FLOODING.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WIND ADVISORY UNTIL 3 AM EST MONDAY FOR MIZ037-038-043-044-050-
056-057-064-065-071-072.
LM...GALE WARNING UNTIL 10 PM EST THIS EVENING FOR LMZ844>849.
&&
$$
SYNOPSIS...93
SHORT TERM...93
LONG TERM...MJS
AVIATION...63
HYDROLOGY...93
MARINE...93
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1257 PM EST SUN NOV 11 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 533 AM EST SUN NOV 11 2012
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW DEEP TROF OVER THE
ROCKIES UPSTREAM OF HI AMPLITUDE RDG IN THE E. VIGOROUS SHRTWV WITH
CLOSED LO AT H5 LIFTING NEWD THRU THE NRN PLAINS IS SUPPORTING 995MB
SFC LO PRES OVER NW MN AT 06Z. ATTENDANT SFC WARM FNT LIES W-E ACRS
NCNTRL WI...WITH SHARP TEMP GRADIENT ACRS THIS BNDRY. AT 05Z...SFC
TEMP WAS 51 AT WAUSAU WI TO 64 AT WISCONSIN RAPIDS LESS THAN 50
MILES TO THE S ACRS THE WARM FNT. THE H85 WARM FNT SEPARATING A 00Z
H85 TEMP OF 13C AT MPX FM 2C AT INL STRETCHES W-E ACRS LK SUP.
VIGOROUS WARM/MOIST ADVECTION WITH H7 WINDS AS HI AS 50-70KTS IN A
RIBBON JUST E OF THE ATTENDANT COLD FNT IN THE PLAINS HAS ADVECTED
PWAT OF NEARLY 1 INCH INTO THE UPR LKS...UP TO 250 PCT OF NORMAL.
NMRS SHRA WITH A FEW ELEVATED TS APPEAR TO BE TIED TO H85 WARM FNT
AND ENHANCED BY VIGOROUS UPR DVGC IN ADVANCE OF 130KT H3 JET MAX
LIFTING NEWD THRU THE PLAISN AND STEEPENING LAPSE RATES ACCOMPANYING
THE VIGOROUS WARM/MOIST ADVCTN AT H85-7. THE TS ARE MAINLY OVER WRN
LK SUP...AND THIS AREA OF PCPN IS LIFTING NEWD THRU LK SUP/THE ERN
CWA AT 06Z...BUT SCT -SHRA ARE ALSO PRESENT IN THE H85 WARM SECTOR S
THRU WI. THESE SHRA ARE TENDING TO DIMINISH WITH TIME. LOOKING TO
THE W...THE REMNANTS OF A LINE OF CONVECTION ARE PRESSING EWD THRU
MN AND INTO NW WI WELL AHEAD OF THE ASSOCIATED OCCLUDED/COLD FNT...
BUT LATEST RADAR TRENDS SHOW THIS BAND OF SHRA IS DIMINISHING. THE
THERMAL CONTRAST ACROSS THIS COLD FNT IS EQUALLY IMPRESSIVE... WITH
00Z H85 TEMPS RANGING FM 13C AT MPX AND OMAHA TO -11C AT BISMARCK.
ANOTHER VIGOROUS SHRTWV APPEARS TO BE ROUNDING THE BASE OF THE TROF
IN THE ROCKIES.
FCST CONCERNS DURING THE SHORT TERM ARE MANY AND INCLUDE SHRA/TS
CHCS THRU TNGT AS WELL AS TRANSITION TO MORE WINTRY WX TNGT AS COLD
FNT TO THE W PASSES THRU UPR MI.
TODAY...LATEST MODELS IN FAIRLY GOOD AGREEMENT SHOWING SFC LO IN MN
MOVING TO NEAR PICKLE LAKE ONTARIO BY 00Z MON WITH ATTENDANT COLD
FNT MOVING TO ABOUT MQT-IMT THEN. GUIDANCE REMAINS IN VERY GOOD
SHOWING H3 JET CORE UP TO 130KT LIFTING NNEWD TO NE MN/WRN LK SUP BY
00Z...WITH INCRSG PCPN COVERAGE MAINLY ALONG AND JUST BEHIND THE FNT
WITH ENHANCED UPR DVGC AND BAND OF SHARP FGEN THAT SHOWS UP BEST AT
H8-7 BEING THE MAIN FORCING MECHANISMS TO LIFT VERY MOIST AIRMASS.
GOING FCST POPS SHOWING INCRSG POPS TO CATEGORICAL OVER MUCH OF THE
W AND CENTRAL SEEM ON TRACK AND ARE IN NEED OF ONLY MINOR
ADJUSTMENTS. PCPN OVER THE MORE CAPPED E SHOULD REMAIN MAINLY SCT
-SHRA TO THE E OF THE INCOMING COLD FNT. EXPECT TEMPS TO RISE INTO
THE BALMY 50S FOLLOWING SFC WARM FROPA. ALTHOUGH THE PASSAGE OF THE
COLD FNT WL OPEN THE DOOR TO COLDER AIR TO MOVE INTO THE W HALF AND
FALLING TEMPS AFT WELL ABV NORMAL RELATIVELY EARLY HI TEMPS
ESPECIALLY OVER THE W...THE APRCH OF THE DISTURBANCE SUPPORTS MODEL
FCST THERMAL FIELDS THAT INDICATE THE PCPN WL REMAIN IN THE FORM OF
RA EVEN AT IWD UNTIL ALMOST 00Z.
TONIGHT...UPR DVGC IN RRQ OF 140KT H3 JET MAX/AXIS OF LO-MID LVL
FGEN ASSOCIATED WITH APRCHG SHRTWV WL BRING CATEGORICAL POPS TO
MAINLY THE E HALF OF THE CWA AS SFC FNT PUSHES SLOWLY TO THE
E...REACHING THE SAULT JUST A FEW HRS BEFORE 12Z MON. BULK OF MODELS
SHOW ENUF DRY MID LVL AIR PUSHING EWD TO LIMIT PCPN AMOUNTS OVER THE
W AND THEN CENTRAL WHERE THE AIR WL TURN COLD ENUF TO SUPPORT
SN...BUT H85 TEMPS FALLING TO -10C TO -14C BY 12Z MON OVER THE W WL
BE SUFFICIENTLY COLD TO BRING AT LEAST SCT LK EFFECT SHSN TO AREAS
FAVORED BY FCST W WIND DESPITE SLIGHTLY LLVL ACYC FLOW. ANY SN/SLEET
ACCUM SHOULD BE UNDER AN INCH. SHARP LLVL COOLING ASSOCIATED WITH
H85-7 FGEN MAX SLOPED FAIRLY FAR TO THE W OF THE SFC FNT MAY CREATE
ELEVATED WARM LYR/POTENTIAL FOR SLEET AS WELL AS SN TO THE CNTRL ZNS
ON THE WRN EDGE OF THE LARGER SYNOPTIC SCALE PCPN AREA TO THE E. THE
E SHOULD REMAIN WARM ENUF FOR MAINLY RA GIVEN FCST H85 TEMPS/H100-85
THKNS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 533 AM EST SUN NOV 11 2012
MAIN FOCUS INITIALLY IN LONG TERM IS DEEP/COLD/MOIST LOW-MID LEVEL
TROUGH EXTENDING FROM ONTARIO TO THE MIDDLE MISSISSIPPI RIVER
VALLEY ON MONDAY. SFC COLD FRONT WILL BE THROUGH UPR MICHIGAN BY 12Z
MONDAY. KEPT HIGHER POPS OVER FAR EAST FOR MAINLY SNOW THROUGH MID
MORNING...BUT WILL BE DRYING OUT ELSEWHERE OVER THE EAST IN WAKE OF
THE FRONT.
ALREADY PLENTY COLD ENOUGH AT H85 /H85 TEMPS AROUND -10C/ TO SUPPORT
LK EFFECT OFF LK SUPERIOR TO START THE DAY GIVEN WATER TEMPS AROUND
+8C. OVER-WATER INSTABILITY RAMPS UP FURTHER THROUGH THE DAY WITH
DELTA T/S WELL OVER 20C BY EVENING IN A MOIST ENVIRONMENT TO H7. NOT
THE USUALLY TYPICAL REALLY COLD BUT REALLY DRY AIRMASS FOR THE LK
EFFECT TO WORK ON...AT LEAST NOT UNTIL LATER MONDAY NIGHT WITH
ARRIVAL OF DRIER AIR AOA H85. NAM/GFS SOUNDINGS INDICATE INVERSION
HEIGHTS OR AT LEAST LAKE EQUILIBRIUM LEVELS TOPPING OUT AROUND 10KFT
AND LOW-LEVEL LAPSE RATES EXCEEDING 9C/KM. SINCE IT IS CHILLY AT SFC
AND ALOFT...MUCH OF THE LAKE CONVECTIVE LAYER WILL BE WITHIN HEART
OF DENDRITIC GROWTH ZONE...BOOSTING SLR/S AND ULTIMATELY SNOWFALL
TOTALS.
PRIMARY QUESTION IS HOW QUICKLY ON MONDAY WILL SIGNIFICANT LK EFFECT
SNOW SHOWERS DEVELOP AND WHERE WILL HEAVIER SNOWS OCCUR THROUGH
MONDAY NIGHT. LOW-LEVEL WINDS IN WAKE OF COLD FRONT ARE MORE FROM
WSW INITIALLY ON MONDAY MORNING WHICH FAVORS MAJORITY OF SNOW
IMPACTING MAINLY NORTHERN PORTIONS OF KEWEENAW PENINSULA. SFC WINDS
GRADUALLY TURN MORE NORTHWEST ON MONDAY EVENING AS SFC TROUGH WORKS
ACROSS LK SUPERIOR AND NORTHERN UPR MICHIGAN. SOUNDINGS INDICATE
THAT EVEN AS SUB H85 WINDS ARE MOSTLY FROM THE WSW MUCH OF MONDAY
THE WINDS FROM H8-H7 SHIFT TO NW DURING THE AFTN OVER WESTERN UPR
MICHIGAN. MAY SEE SITUATION WHERE MORE OF A WIDESPREAD SNOW ENVELOPS
MOST OF NW/W UPR MICHIGAN BY MID AFTN DUE TO COOL/MOIST PROFILE
UPWARDS OF H7. MEANWHILE...BLYR WINDS WOULD FAVOR CONVERGENCE BAND
OF HEAVIER SNOW TO SET UP SOMEWHERE ALONG WEST SIDE OF KEWEENAW THEN
GRADUALLY SINKING SOUTHWARD LATE IN THE DAY INTO THE EVENING WITH
THE SFC WIND SHIFT. ALL FACTORS ARE FAVORABLE FOR INTENSE SNOW RATES
AFTN-EVENING WHERE THE BAND DEVELOPS. INSTABILITY PARAMETERS AND
LOCAL GUIDANCE ALONG WITH LAKE SNOW PARAMETER DEVELOPED BY NWS
OFFICE IN GAYLORD MI ALL POINT TO HEAVY SNOWFALL RATES /AT LEAST 1"
PER HR/ LATER MONDAY AFTN AND MONDAY EVENING OVR NW UPR MICHIGAN.
CURRENTLY HAVE POTENTIAL FOR SNOW MENTIONED IN HAZARDOUS WEATHER
OUTLOOK FOR NW CWA. CANNOT FORGET THE FAR NORTHEAST CWA AS WELL WITH
WINDS SHIFTING ONSHORE AND LEADING TO POTENTIAL OF DOMINANT BAND OF
SNOW IMPACTING THOSE AREAS AS WELL...MAINLY EAST OF P53 INTO
NORTHERN LUCE COUNTY. AS MENTIONED IN PREVIOUS DISCUSSION...MORE
RESIDENCE TIME OVER THE WARMER LAKE WATERS AND A BIT MORE WARMER
AIRMASS OVERALL MAY ACT TO LIMIT SNOW AMOUNTS COMPARED TO WHAT IS
EXPECTED TO OCCUR OVER NW UPR MICHIGAN. SOME SNOW ACCUMULATIONS ARE
LIKELY THOUGH.
LATER MONDAY NIGHT AND FOR SURE INTO MID MORNING TUESDAY...WILL SEE
LK EFFECT DIMINISH SIGNIFICANTLY MAINLY DUE TO DEPARTURE OF MOISTURE
ABOVE H85 AND AS STEADILY WARMING TEMPS AT TOP OF 5KFT INVERSION.
MOISTURE DECREASES DRAMATICALLY BY 12Z TUESDAY...ESPECIALLY IN THE
WEST. COULD EVEN SEE SKIES BECOME MOSTLY CLEAR OVER FAR SOUTH AWAY
FROM EFFECTS OFF THE LAKE. IN ANY CASE...WHAT LAKE EFFECT IS LEFT
AT THAT TIME WILL BE SHADOW OF WHAT WILL HAVE JUST OCCURRED 12 HR
PREVIOUSLY. NO REAL CHANGES TO POPS FOR MONDAY THROUGH MONDAY NIGHT
AND INTO TUESDAY...JUST SOME TWEAKING TO MATCH LATEST MODEL TRENDS.
DID INCREASE SNOW AMOUNTS SOME OVER NORTHWEST GIVEN INCREASING
CONFIDENCE IN OVERALL SCENARIO. CURRENTLY FORECASTED SNOW AMOUNTS
SUPPORT ADVISORY HEADLINES EVENTUALLY. THAT SAID...CERTAINLY
POSSIBLE THAT AT LEAST ISOLD LOCATIONS FROM ONTONAGON THROUGH
HOUGHTON AND KEWEENAW COUTNIES MAY SEE WARNING CRITERIA SNOWFALL
FROM THIS EARLY SEASON LAKE SNOW EVENT. ON A SIDE NOTE...WINDS IN
THE STRONGER CONVERGENCE AREAS ACROSS KEWEENAW MAY TOP OUT 30-40 MPH
ON MONDAY AND MONDAY EVENING. SO IN ADDITION TO THE HEAVY SNOW COULD
ALSO SEE STRONG/GUSTY WINDS WITHIN THOSE HEAVIER SNOW SQUALLS.
PLAN TO MENTION THIS IN THE HAZARDOUS WEATHER OUTLOOK.
REST OF LONG TERM...PRETTY QUIET OVERALL AS PACIFIC FLOW ALOFT WILL
BE IN CONTROL. SFC HIGH BUILDS IN LATER TUESDAY AND MOVES EAST ON
WEDNESDAY. LOWERED MINS ON TUESDAY NIGHT WITH COLD AIRMASS IN PLACE.
MID CLOUDS INCREASE LATE BUT SEEMED REASONABLE TO START THE NIGHT
TEMPS COULD FALL OFF INTO THE TEENS BEFORE BECOMING MORE STEADY LATE.
WEDNESDAY MAY END UP FAIRLY CLOUDY...BUT REALLY WHAT ELSE IS NEW
LATELY. A LOT OF MID CLOUDS SHOW UP IN THE MODELS...BUT DRY SUB H85
AIR DUE TO LINGERING AFFECTS OF THE SFC HIGH AND NOT VERY STRONG
LIFT ALOFT RESULT IN KEEPING DRY FORECAST GOING FOR CWA. WEAK WARM
AIR ADVECTION AND ADDITIONAL MOISTURE ADVECTION AHEAD OF SFC TROUGH
MOVING ACROSS ONTARIO BY THURSDAY MORNING COULD PROVIDE CHANCE FOR
SOME LGT SNOW/FLURRIES ON WEDNESDAY NIGHT. DRY FORECAST TO CLOSE THE
WEEK AND THROUGH NEXT SATURDAY WITH LACK OF SYSTEMS MOVING THROUGH
IN THE WESTERLY FLOW. SW FLOW IN LOWER LEVELS FRIDAY/SATURDAY MAY
ALLOW FOR TEMPS TO PUSH SLIGHTY ABOVE NORMAL.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON)
ISSUED AT 1256 PM EST SUN NOV 11 2012
CONDITIONS WILL CONTINUE TO DETERIORATE AS SHRA OVERSPREADS WESTERN
AND CENTRAL UPPER MI IN RELATION TO A DISTURBANCE RIDING NEWD ALONG
COLD FRONT...CURRENTLY OVER FAR WESTERN UPPER MI. KEPT TAF SITES
WITHIN FUEL ALTERNATE CATEGORIES THROUGH THIS EVENING...THOUGH AS
MENTIONED BY PREVIOUS FORECAST...LIFR CONDITIONS CAN NOT BE RULED
OUT AT SOME POINT...ESPECIALLY AT CMX THIS AFTN/EVNG WITH GUSTY
UPSLOPE W WIND BEHIND THE COLD FROPA. EXPECT THE ARRIVAL OF DRIER
AIR TO CAUSE THE PCPN TO DIMINISH JUST AS ENUF COLD AIR SURGES INTO
THE AREA TO CHANGE THE RA TO SN. THE BEST CHC FOR HEAVIER -SHSN
LATER TNGT WL BE AT THE MORE EXPOSED CMX LOCATION...WHERE GUSTY
WINDS WL LINGER AS WELL. OTHERWISE...DRY AIR WILL CONTINUE TO
IMPROVE CIG CONDITIONS TO VFR AT KIWD AND KSAW BY MONDAY MORNING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 533 AM EST SUN NOV 11 2012
EXPECT S WINDS UP TO 25 TO 30 KTS...STRONGEST OVER THE E HALF UNDER
TIGHTER PRES GRADIENT...IN ADVANCE OF AN APPROACHING COLD FRONT TO
SHIFT TO THE W FOLLOWING THE COLD FROPA OVER THE W THIS AFTERNOON AND
THEN OVER THE CENTRAL AND E TONIGHT AS MUCH COLDER AIR FLOWS OVER THE
RELATIVELY WARM LAKE WATERS AND ENHANCES MIXING OF STRONGER WINDS TO
THE SURFACE.
PRESSURE GRADIENT STAYS TIGHT ON MONDAY WITH WEST WINDS UP TO 30 KTS
AND OCCASIONAL GALE GUSTS TO 35 KTS. PRESSURE GRADIENT SLACKENS
MONDAY NIGHT AND TUESDAY WITH WINDS DIMINISHING BLO 25 KTS. A LOW
PRESSURE TROUGH WILL PUSH ACROSS NORTHERN ONTARIO ON THURSDAY. SOUTH
WINDS AHEAD OF THE TROUGH COULD REACH 25 KTS OVER EASTERN SECTIONS
OF LK SUPERIOR WEDNESDAY AND WEDNESDAY NIGHT. WINDS TO FINISH UP THE
WEEK WILL BE BLO 20 KTS AS PRESSURE GRADIENT DIMINISHES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...JMW
MARINE...KC/JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
718 AM EST SUN NOV 11 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 533 AM EST SUN NOV 11 2012
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW DEEP TROF OVER THE
ROCKIES UPSTREAM OF HI AMPLITUDE RDG IN THE E. VIGOROUS SHRTWV WITH
CLOSED LO AT H5 LIFTING NEWD THRU THE NRN PLAINS IS SUPPORTING 995MB
SFC LO PRES OVER NW MN AT 06Z. ATTENDANT SFC WARM FNT LIES W-E ACRS
NCNTRL WI...WITH SHARP TEMP GRADIENT ACRS THIS BNDRY. AT 05Z...SFC
TEMP WAS 51 AT WAUSAU WI TO 64 AT WISCONSIN RAPIDS LESS THAN 50
MILES TO THE S ACRS THE WARM FNT. THE H85 WARM FNT SEPARATING A 00Z
H85 TEMP OF 13C AT MPX FM 2C AT INL STRETCHES W-E ACRS LK SUP.
VIGOROUS WARM/MOIST ADVECTION WITH H7 WINDS AS HI AS 50-70KTS IN A
RIBBON JUST E OF THE ATTENDANT COLD FNT IN THE PLAINS HAS ADVECTED
PWAT OF NEARLY 1 INCH INTO THE UPR LKS...UP TO 250 PCT OF NORMAL.
NMRS SHRA WITH A FEW ELEVATED TS APPEAR TO BE TIED TO H85 WARM FNT
AND ENHANCED BY VIGOROUS UPR DVGC IN ADVANCE OF 130KT H3 JET MAX
LIFTING NEWD THRU THE PLAISN AND STEEPENING LAPSE RATES ACCOMPANYING
THE VIGOROUS WARM/MOIST ADVCTN AT H85-7. THE TS ARE MAINLY OVER WRN
LK SUP...AND THIS AREA OF PCPN IS LIFTING NEWD THRU LK SUP/THE ERN
CWA AT 06Z...BUT SCT -SHRA ARE ALSO PRESENT IN THE H85 WARM SECTOR S
THRU WI. THESE SHRA ARE TENDING TO DIMINISH WITH TIME. LOOKING TO
THE W...THE REMNANTS OF A LINE OF CONVECTION ARE PRESSING EWD THRU
MN AND INTO NW WI WELL AHEAD OF THE ASSOCIATED OCCLUDED/COLD FNT...
BUT LATEST RADAR TRENDS SHOW THIS BAND OF SHRA IS DIMINISHING. THE
THERMAL CONTRAST ACROSS THIS COLD FNT IS EQUALLY IMPRESSIVE... WITH
00Z H85 TEMPS RANGING FM 13C AT MPX AND OMAHA TO -11C AT BISMARCK.
ANOTHER VIGOROUS SHRTWV APPEARS TO BE ROUNDING THE BASE OF THE TROF
IN THE ROCKIES.
FCST CONCERNS DURING THE SHORT TERM ARE MANY AND INCLUDE SHRA/TS
CHCS THRU TNGT AS WELL AS TRANSITION TO MORE WINTRY WX TNGT AS COLD
FNT TO THE W PASSES THRU UPR MI.
TODAY...LATEST MODELS IN FAIRLY GOOD AGREEMENT SHOWING SFC LO IN MN
MOVING TO NEAR PICKLE LAKE ONTARIO BY 00Z MON WITH ATTENDANT COLD
FNT MOVING TO ABOUT MQT-IMT THEN. GUIDANCE REMAINS IN VERY GOOD
SHOWING H3 JET CORE UP TO 130KT LIFTING NNEWD TO NE MN/WRN LK SUP BY
00Z...WITH INCRSG PCPN COVERAGE MAINLY ALONG AND JUST BEHIND THE FNT
WITH ENHANCED UPR DVGC AND BAND OF SHARP FGEN THAT SHOWS UP BEST AT
H8-7 BEING THE MAIN FORCING MECHANISMS TO LIFT VERY MOIST AIRMASS.
GOING FCST POPS SHOWING INCRSG POPS TO CATEGORICAL OVER MUCH OF THE
W AND CENTRAL SEEM ON TRACK AND ARE IN NEED OF ONLY MINOR
ADJUSTMENTS. PCPN OVER THE MORE CAPPED E SHOULD REMAIN MAINLY SCT
-SHRA TO THE E OF THE INCOMING COLD FNT. EXPECT TEMPS TO RISE INTO
THE BALMY 50S FOLLOWING SFC WARM FROPA. ALTHOUGH THE PASSAGE OF THE
COLD FNT WL OPEN THE DOOR TO COLDER AIR TO MOVE INTO THE W HALF AND
FALLING TEMPS AFT WELL ABV NORMAL RELATIVELY EARLY HI TEMPS
ESPECIALLY OVER THE W...THE APRCH OF THE DISTURBANCE SUPPORTS MODEL
FCST THERMAL FIELDS THAT INDICATE THE PCPN WL REMAIN IN THE FORM OF
RA EVEN AT IWD UNTIL ALMOST 00Z.
TONIGHT...UPR DVGC IN RRQ OF 140KT H3 JET MAX/AXIS OF LO-MID LVL
FGEN ASSOCIATED WITH APRCHG SHRTWV WL BRING CATEGORICAL POPS TO
MAINLY THE E HALF OF THE CWA AS SFC FNT PUSHES SLOWLY TO THE
E...REACHING THE SAULT JUST A FEW HRS BEFORE 12Z MON. BULK OF MODELS
SHOW ENUF DRY MID LVL AIR PUSHING EWD TO LIMIT PCPN AMOUNTS OVER THE
W AND THEN CENTRAL WHERE THE AIR WL TURN COLD ENUF TO SUPPORT
SN...BUT H85 TEMPS FALLING TO -10C TO -14C BY 12Z MON OVER THE W WL
BE SUFFICIENTLY COLD TO BRING AT LEAST SCT LK EFFECT SHSN TO AREAS
FAVORED BY FCST W WIND DESPITE SLIGHTLY LLVL ACYC FLOW. ANY SN/SLEET
ACCUM SHOULD BE UNDER AN INCH. SHARP LLVL COOLING ASSOCIATED WITH
H85-7 FGEN MAX SLOPED FAIRLY FAR TO THE W OF THE SFC FNT MAY CREATE
ELEVATED WARM LYR/POTENTIAL FOR SLEET AS WELL AS SN TO THE CNTRL ZNS
ON THE WRN EDGE OF THE LARGER SYNOPTIC SCALE PCPN AREA TO THE E. THE
E SHOULD REMAIN WARM ENUF FOR MAINLY RA GIVEN FCST H85 TEMPS/H100-85
THKNS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 533 AM EST SUN NOV 11 2012
MAIN FOCUS INITIALLY IN LONG TERM IS DEEP/COLD/MOIST LOW-MID LEVEL
TROUGH EXTENDING FROM ONTARIO TO THE MIDDLE MISSISSIPPI RIVER
VALLEY ON MONDAY. SFC COLD FRONT WILL BE THROUGH UPR MICHIGAN BY 12Z
MONDAY. KEPT HIGHER POPS OVER FAR EAST FOR MAINLY SNOW THROUGH MID
MORNING...BUT WILL BE DRYING OUT ELSEWHERE OVER THE EAST IN WAKE OF
THE FRONT.
ALREADY PLENTY COLD ENOUGH AT H85 /H85 TEMPS AROUND -10C/ TO SUPPORT
LK EFFECT OFF LK SUPERIOR TO START THE DAY GIVEN WATER TEMPS AROUND
+8C. OVER-WATER INSTABILITY RAMPS UP FURTHER THROUGH THE DAY WITH
DELTA T/S WELL OVER 20C BY EVENING IN A MOIST ENVIRONMENT TO H7. NOT
THE USUALLY TYPICAL REALLY COLD BUT REALLY DRY AIRMASS FOR THE LK
EFFECT TO WORK ON...AT LEAST NOT UNTIL LATER MONDAY NIGHT WITH
ARRIVAL OF DRIER AIR AOA H85. NAM/GFS SOUNDINGS INDICATE INVERSION
HEIGHTS OR AT LEAST LAKE EQUILIBRIUM LEVELS TOPPING OUT AROUND 10KFT
AND LOW-LEVEL LAPSE RATES EXCEEDING 9C/KM. SINCE IT IS CHILLY AT SFC
AND ALOFT...MUCH OF THE LAKE CONVECTIVE LAYER WILL BE WITHIN HEART
OF DENDRITIC GROWTH ZONE...BOOSTING SLR/S AND ULTIMATELY SNOWFALL
TOTALS.
PRIMARY QUESTION IS HOW QUICKLY ON MONDAY WILL SIGNIFICANT LK EFFECT
SNOW SHOWERS DEVELOP AND WHERE WILL HEAVIER SNOWS OCCUR THROUGH
MONDAY NIGHT. LOW-LEVEL WINDS IN WAKE OF COLD FRONT ARE MORE FROM
WSW INITIALLY ON MONDAY MORNING WHICH FAVORS MAJORITY OF SNOW
IMPACTING MAINLY NORTHERN PORTIONS OF KEWEENAW PENINSULA. SFC WINDS
GRADUALLY TURN MORE NORTHWEST ON MONDAY EVENING AS SFC TROUGH WORKS
ACROSS LK SUPERIOR AND NORTHERN UPR MICHIGAN. SOUNDINGS INDICATE
THAT EVEN AS SUB H85 WINDS ARE MOSTLY FROM THE WSW MUCH OF MONDAY
THE WINDS FROM H8-H7 SHIFT TO NW DURING THE AFTN OVER WESTERN UPR
MICHIGAN. MAY SEE SITUATION WHERE MORE OF A WIDESPREAD SNOW ENVELOPS
MOST OF NW/W UPR MICHIGAN BY MID AFTN DUE TO COOL/MOIST PROFILE
UPWARDS OF H7. MEANWHILE...BLYR WINDS WOULD FAVOR CONVERGENCE BAND
OF HEAVIER SNOW TO SET UP SOMEWHERE ALONG WEST SIDE OF KEWEENAW THEN
GRADUALLY SINKING SOUTHWARD LATE IN THE DAY INTO THE EVENING WITH
THE SFC WIND SHIFT. ALL FACTORS ARE FAVORABLE FOR INTENSE SNOW RATES
AFTN-EVENING WHERE THE BAND DEVELOPS. INSTABILITY PARAMETERS AND
LOCAL GUIDANCE ALONG WITH LAKE SNOW PARAMETER DEVELOPED BY NWS
OFFICE IN GAYLORD MI ALL POINT TO HEAVY SNOWFALL RATES /AT LEAST 1"
PER HR/ LATER MONDAY AFTN AND MONDAY EVENING OVR NW UPR MICHIGAN.
CURRENTLY HAVE POTENTIAL FOR SNOW MENTIONED IN HAZARDOUS WEATHER
OUTLOOK FOR NW CWA. CANNOT FORGET THE FAR NORTHEAST CWA AS WELL WITH
WINDS SHIFTING ONSHORE AND LEADING TO POTENTIAL OF DOMINANT BAND OF
SNOW IMPACTING THOSE AREAS AS WELL...MAINLY EAST OF P53 INTO
NORTHERN LUCE COUNTY. AS MENTIONED IN PREVIOUS DISCUSSION...MORE
RESIDENCE TIME OVER THE WARMER LAKE WATERS AND A BIT MORE WARMER
AIRMASS OVERALL MAY ACT TO LIMIT SNOW AMOUNTS COMPARED TO WHAT IS
EXPECTED TO OCCUR OVER NW UPR MICHIGAN. SOME SNOW ACCUMULATIONS ARE
LIKELY THOUGH.
LATER MONDAY NIGHT AND FOR SURE INTO MID MORNING TUESDAY...WILL SEE
LK EFFECT DIMINISH SIGNIFICANTLY MAINLY DUE TO DEPARTURE OF MOISTURE
ABOVE H85 AND AS STEADILY WARMING TEMPS AT TOP OF 5KFT INVERSION.
MOISTURE DECREASES DRAMATICALLY BY 12Z TUESDAY...ESPECIALLY IN THE
WEST. COULD EVEN SEE SKIES BECOME MOSTLY CLEAR OVER FAR SOUTH AWAY
FROM EFFECTS OFF THE LAKE. IN ANY CASE...WHAT LAKE EFFECT IS LEFT
AT THAT TIME WILL BE SHADOW OF WHAT WILL HAVE JUST OCCURRED 12 HR
PREVIOUSLY. NO REAL CHANGES TO POPS FOR MONDAY THROUGH MONDAY NIGHT
AND INTO TUESDAY...JUST SOME TWEAKING TO MATCH LATEST MODEL TRENDS.
DID INCREASE SNOW AMOUNTS SOME OVER NORTHWEST GIVEN INCREASING
CONFIDENCE IN OVERALL SCENARIO. CURRENTLY FORECASTED SNOW AMOUNTS
SUPPORT ADVISORY HEADLINES EVENTUALLY. THAT SAID...CERTAINLY
POSSIBLE THAT AT LEAST ISOLD LOCATIONS FROM ONTONAGON THROUGH
HOUGHTON AND KEWEENAW COUTNIES MAY SEE WARNING CRITERIA SNOWFALL
FROM THIS EARLY SEASON LAKE SNOW EVENT. ON A SIDE NOTE...WINDS IN
THE STRONGER CONVERGENCE AREAS ACROSS KEWEENAW MAY TOP OUT 30-40 MPH
ON MONDAY AND MONDAY EVENING. SO IN ADDITION TO THE HEAVY SNOW COULD
ALSO SEE STRONG/GUSTY WINDS WITHIN THOSE HEAVIER SNOW SQUALLS.
PLAN TO MENTION THIS IN THE HAZARDOUS WEATHER OUTLOOK.
REST OF LONG TERM...PRETTY QUIET OVERALL AS PACIFIC FLOW ALOFT WILL
BE IN CONTROL. SFC HIGH BUILDS IN LATER TUESDAY AND MOVES EAST ON
WEDNESDAY. LOWERED MINS ON TUESDAY NIGHT WITH COLD AIRMASS IN PLACE.
MID CLOUDS INCREASE LATE BUT SEEMED REASONABLE TO START THE NIGHT
TEMPS COULD FALL OFF INTO THE TEENS BEFORE BECOMING MORE STEADY LATE.
WEDNESDAY MAY END UP FAIRLY CLOUDY...BUT REALLY WHAT ELSE IS NEW
LATELY. A LOT OF MID CLOUDS SHOW UP IN THE MODELS...BUT DRY SUB H85
AIR DUE TO LINGERING AFFECTS OF THE SFC HIGH AND NOT VERY STRONG
LIFT ALOFT RESULT IN KEEPING DRY FORECAST GOING FOR CWA. WEAK WARM
AIR ADVECTION AND ADDITIONAL MOISTURE ADVECTION AHEAD OF SFC TROUGH
MOVING ACROSS ONTARIO BY THURSDAY MORNING COULD PROVIDE CHANCE FOR
SOME LGT SNOW/FLURRIES ON WEDNESDAY NIGHT. DRY FORECAST TO CLOSE THE
WEEK AND THROUGH NEXT SATURDAY WITH LACK OF SYSTEMS MOVING THROUGH
IN THE WESTERLY FLOW. SW FLOW IN LOWER LEVELS FRIDAY/SATURDAY MAY
ALLOW FOR TEMPS TO PUSH SLIGHTY ABOVE NORMAL.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 716 AM EST SUN NOV 11 2012
EXPECT PREDOMINANT VFR CONDITIONS AND SOME LLWS AT ALL 3 SITES FOR A
TIME THIS MRNG WITH INFLUX OF RELATIVELY DRY/CAPPED AIRMASS IN THE
WAKE OF EARLIER WARM FROPA. AS A COLD FNT PRESSES E INTO UPR MI BY
THIS AFTN...EXPECT SHRA TO ARRIVE W-E WITH CONDITIONS DETERIORATING
TO MVFR THEN IFR AS A DISTURBANCE RIDING NEWD ALONG THE FNT CAUSES
AN EXPANSION OF RA AREA. LIFR CONDITIONS WL BE POSSIBLE FOR A TIME
AS WELL...ESPECIALLY AT CMX THIS AFTN/EVNG WITH GUSTY USPLOPE W WIND
BEHIND THE COLD FROPA. EXPECT THE ARRIVAL OF DRIER AIR TO CAUSE THE
PCPN TO DIMINISH JUST AS ENUF COLD AIR SURGES INTO THE AREA TO
CHANGE THE RA TO SN. THE BEST CHC FOR HEAVIER -SHSN/PERHAPS IFR WX
LATER TNGT WL BE AT THE MORE EXPOSED CMX LOCATION...WHERE GUSTY
WINDS WL LINGER AS WELL.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 533 AM EST SUN NOV 11 2012
EXPECT S WINDS UP TO 25 TO 30 KTS...STRONGEST OVER THE E HALF UNDER
TIGHTER PRES GRADIENT...IN ADVANCE OF AN APPROACHING COLD FRONT TO
SHIFT TO THE W FOLLOWING THE COLD FROPA OVER THE W THIS AFTERNOON AND
THEN OVER THE CENTRAL AND E TONIGHT AS MUCH COLDER AIR FLOWS OVER THE
RELATIVELY WARM LAKE WATERS AND ENHANCES MIXING OF STRONGER WINDS TO
THE SURFACE.
PRESSURE GRADIENT STAYS TIGHT ON MONDAY WITH WEST WINDS UP TO 30 KTS
AND OCCASIONAL GALE GUSTS TO 35 KTS. PRESSURE GRADIENT SLACKENS
MONDAY NIGHT AND TUESDAY WITH WINDS DIMINISHING BLO 25 KTS. A LOW
PRESSURE TROUGH WILL PUSH ACROSS NORTHERN ONTARIO ON THURSDAY. SOUTH
WINDS AHEAD OF THE TROUGH COULD REACH 25 KTS OVER EASTERN SECTIONS
OF LK SUPERIOR WEDNESDAY AND WEDNESDAY NIGHT. WINDS TO FINISH UP THE
WEEK WILL BE BLO 20 KTS AS PRESSURE GRADIENT DIMINISHES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...KC
MARINE...KC/JLA
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
627 AM EST SUN NOV 11 2012
.SYNOPSIS...
ISSUED AT 328 AM EST SUN NOV 11 2012
STRONG SOUTH WINDS WILL DEVELOP ACROSS THE REGION TODAY AHEAD OF A
STRONG COLD FRONT. A PUSH OF WARM AIR WILL SEND TEMPERATURES INTO
THE UPPER 60S A MANY LOCATIONS THIS AFTERNOON. SHOWERS WILL DEVELOP
LATE IN THE DAY AND CONTINUE TONIGHT AS THE FRONT MOVES ACROSS THE
AREA. MUCH COLDER AIR ALONG WITH RAIN AND SNOW SHOWERS WILL MOVE
INTO WEST MICHIGAN MONDAY. HIGH TEMPERATURES WILL SLOWLY FALL DURING
THE DAY AND ONLY REACH AROUND 40 DEGREES TUESDAY. MAINLY DRY WEATHER
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 328 AM EST SUN NOV 11 2012
FORECAST CONCERNS DEAL WITH THE WIND POTENTIAL TODAY AND PCPN TRENDS
TONIGHT/MONDAY.
THE GOING FORECAST IS LARGELY ON TRACK. HOWEVER...WINDS APPEAR A BIT
STRONGER ACROSS THE WRN CWA AS THE GRADIENT TIGHTENS AHEAD OF THE
COLD FRONT. AS SUCH WE ISSUED A WIND ADVISORY FOR THE WRN 1/2 OF THE
CWA. WINDS ARE ALREADY GUSTING TO 36 KITS AT KMKG AND WILL LIKELY
INCREASE A BIT MORE AS THE SUN RISES AND BETTER MIXING OCCURS.
STRONG 65KT LLJ MOVES OVER THE WRN CWA LATE THIS AFTERNOON.
LATEST HRRR HAS A PRETTY GOOD HANDLE ON THE SHOWERS MOVING ACROSS
NRN IL/WISCONSIN. THESE ARE AHEAD OF THE COLD FRONT AND DISSIPATE
SOMEWHAT AS THEY MOVE EWD THIS AFTERNOON. AS A RESULT...WE
ANTICIPATE A DRY DAY. ABUNDANT MID CLOUD WILL BE PRESENT AND THIS
WILL LIMIT MIXING A BIT BUT NOT ENOUGH TO PREVENT SUSTAINED 25 TO 30
MPH WINDS. FROPA IS ON TRACK FOR MIDNIGHT-4AM TIME FRAME. TEMPS WILL
SLOWLY FALL MONDAY AS H8 TEMPS FALL TO -12C. RAIN WILL MIX WITH SNOW
AFTER FROPA THEN BECOME SHSN AS THE THERMAL PROFILE QUICKLY FALLS
BELOW 0C. NOT LOOKING FOR ACCUMS AT THIS POINT. THOUGH IT/S POSSIBLE
A FEW HIGHER ELEVATIONS ACROSS THE NRN CWA COULD SEE A COUPLE OF
TENTHS.
TUESDAY LOOKS DRY BUT CHILLY WITH HIGHS AROUND 40.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 328 AM EST SUN NOV 11 2012
FOR THE EXTENDED PERIOD...THE CORE OF THE ARCTIC AIR REMAINS WELL
NORTH OF THE REGION. ONE OF THE MAIN REASONS FOR THIS IS THE ZONAL
MID LEVEL FLOW THAT SETS UP ACROSS NORTH AMERICA FOR THE PERIOD.
HERE IN MI...WE WILL SEE ONLY A WEAKENING COLD FRONT ARRIVING THU.
IF THERE IS ANY PRECIPITATION WITH THIS SHALLOW FEATURE...IT WILL BE
LIMITED AS VERY LITTLE MOISTURE AND LIFT WILL BE IN PLACE.
TEMPERATURES AT 850 MB CLIMB THU INTO SAT...SO WE WILL LIKELY SEE A
GENERAL WARMING TREND. ALTHOUGH...GIVEN THE MID LEVEL
FLOW...PACIFIC MOISTURE COULD CAUSE PERIODS OF CLOUDS THAT WOULD
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING)
ISSUED AT 620 AM EST SUN NOV 11 2012
SOUTH TO SOUTHWEST FLOW AHEAD OF THE COLD FRONT WILL INCREASE
TODAY AS WE HEAT UP. GUSTS OVER 25 KNOTS ARE EXPECTED FOR ALL TAF
SITES. LOCAL GUSTS OVER 35 KNOTS ARE POSSIBLE. WINDS SHIFT TO THE
WEST AS THE FRONT PASSES THOUGH LATE TONIGHT OR EARLY MON. THE
LACK OF LOW LEVEL MOISTURE WILL KEEP CONDITIONS VFR THROUGH SUNSET
LATER THIS AFTERNOON. HOWEVER WITH THE MOISTURE INCREASING
TONIGHT...THIS WILL CAUSE CONDITIONS TO LOWER TO MVFR WITH AN
INCREASED RISK OF IFR BEFORE DAYBREAK ON MONDAY.
&&
.MARINE...
ISSUED AT 328 AM EST SUN NOV 11 2012
GIVEN THAT WINDS ALONG THE LAKESHORE ARE ALREADY GUSTING NEAR
35KTS...DECIDED TO RUN WITH THE GALE WARNING NOW AND DISCONTINUE THE
SCA. GALES TO 40KTS EXPECTED TODAY WILL BUILD WAVES TO 5 TO 8 FEET.
&&
.HYDROLOGY...
ISSUED AT 328 AM EST SUN NOV 11 2012
A THIRD OF AN INCH OF PCPN IS EXPECTED AHEAD OF THE COLD FRONT
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WIND ADVISORY UNTIL 3 AM EST MONDAY FOR MIZ037-038-043-044-050-
056-057-064-065-071-072.
LM...GALE WARNING UNTIL 10 PM EST THIS EVENING FOR LMZ844>849.
&&
$$
SYNOPSIS...93
SHORT TERM...93
LONG TERM...MJS
AVIATION...MJS
HYDROLOGY...93
MARINE...93
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
536 AM EST SUN NOV 11 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 533 AM EST SUN NOV 11 2012
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW DEEP TROF OVER THE
ROCKIES UPSTREAM OF HI AMPLITUDE RDG IN THE E. VIGOROUS SHRTWV WITH
CLOSED LO AT H5 LIFTING NEWD THRU THE NRN PLAINS IS SUPPORTING 995MB
SFC LO PRES OVER NW MN AT 06Z. ATTENDANT SFC WARM FNT LIES W-E ACRS
NCNTRL WI...WITH SHARP TEMP GRADIENT ACRS THIS BNDRY. AT 05Z...SFC
TEMP WAS 51 AT WAUSAU WI TO 64 AT WISCONSIN RAPIDS LESS THAN 50
MILES TO THE S ACRS THE WARM FNT. THE H85 WARM FNT SEPARATING A 00Z
H85 TEMP OF 13C AT MPX FM 2C AT INL STRETCHES W-E ACRS LK SUP.
VIGOROUS WARM/MOIST ADVECTION WITH H7 WINDS AS HI AS 50-70KTS IN A
RIBBON JUST E OF THE ATTENDANT COLD FNT IN THE PLAINS HAS ADVECTED
PWAT OF NEARLY 1 INCH INTO THE UPR LKS...UP TO 250 PCT OF NORMAL.
NMRS SHRA WITH A FEW ELEVATED TS APPEAR TO BE TIED TO H85 WARM FNT
AND ENHANCED BY VIGOROUS UPR DVGC IN ADVANCE OF 130KT H3 JET MAX
LIFTING NEWD THRU THE PLAISN AND STEEPENING LAPSE RATES ACCOMPANYING
THE VIGOROUS WARM/MOIST ADVCTN AT H85-7. THE TS ARE MAINLY OVER WRN
LK SUP...AND THIS AREA OF PCPN IS LIFTING NEWD THRU LK SUP/THE ERN
CWA AT 06Z...BUT SCT -SHRA ARE ALSO PRESENT IN THE H85 WARM SECTOR S
THRU WI. THESE SHRA ARE TENDING TO DIMINISH WITH TIME. LOOKING TO
THE W...THE REMNANTS OF A LINE OF CONVECTION ARE PRESSING EWD THRU
MN AND INTO NW WI WELL AHEAD OF THE ASSOCIATED OCCLUDED/COLD FNT...
BUT LATEST RADAR TRENDS SHOW THIS BAND OF SHRA IS DIMINISHING. THE
THERMAL CONTRAST ACROSS THIS COLD FNT IS EQUALLY IMPRESSIVE... WITH
00Z H85 TEMPS RANGING FM 13C AT MPX AND OMAHA TO -11C AT BISMARCK.
ANOTHER VIGOROUS SHRTWV APPEARS TO BE ROUNDING THE BASE OF THE TROF
IN THE ROCKIES.
FCST CONCERNS DURING THE SHORT TERM ARE MANY AND INCLUDE SHRA/TS
CHCS THRU TNGT AS WELL AS TRANSITION TO MORE WINTRY WX TNGT AS COLD
FNT TO THE W PASSES THRU UPR MI.
TODAY...LATEST MODELS IN FAIRLY GOOD AGREEMENT SHOWING SFC LO IN MN
MOVING TO NEAR PICKLE LAKE ONTARIO BY 00Z MON WITH ATTENDANT COLD
FNT MOVING TO ABOUT MQT-IMT THEN. GUIDANCE REMAINS IN VERY GOOD
SHOWING H3 JET CORE UP TO 130KT LIFTING NNEWD TO NE MN/WRN LK SUP BY
00Z...WITH INCRSG PCPN COVERAGE MAINLY ALONG AND JUST BEHIND THE FNT
WITH ENHANCED UPR DVGC AND BAND OF SHARP FGEN THAT SHOWS UP BEST AT
H8-7 BEING THE MAIN FORCING MECHANISMS TO LIFT VERY MOIST AIRMASS.
GOING FCST POPS SHOWING INCRSG POPS TO CATEGORICAL OVER MUCH OF THE
W AND CENTRAL SEEM ON TRACK AND ARE IN NEED OF ONLY MINOR
ADJUSTMENTS. PCPN OVER THE MORE CAPPED E SHOULD REMAIN MAINLY SCT
-SHRA TO THE E OF THE INCOMING COLD FNT. EXPECT TEMPS TO RISE INTO
THE BALMY 50S FOLLOWING SFC WARM FROPA. ALTHOUGH THE PASSAGE OF THE
COLD FNT WL OPEN THE DOOR TO COLDER AIR TO MOVE INTO THE W HALF AND
FALLING TEMPS AFT WELL ABV NORMAL RELATIVELY EARLY HI TEMPS
ESPECIALLY OVER THE W...THE APRCH OF THE DISTURBANCE SUPPORTS MODEL
FCST THERMAL FIELDS THAT INDICATE THE PCPN WL REMAIN IN THE FORM OF
RA EVEN AT IWD UNTIL ALMOST 00Z.
TONIGHT...UPR DVGC IN RRQ OF 140KT H3 JET MAX/AXIS OF LO-MID LVL
FGEN ASSOCIATED WITH APRCHG SHRTWV WL BRING CATEGORICAL POPS TO
MAINLY THE E HALF OF THE CWA AS SFC FNT PUSHES SLOWLY TO THE
E...REACHING THE SAULT JUST A FEW HRS BEFORE 12Z MON. BULK OF MODELS
SHOW ENUF DRY MID LVL AIR PUSHING EWD TO LIMIT PCPN AMOUNTS OVER THE
W AND THEN CENTRAL WHERE THE AIR WL TURN COLD ENUF TO SUPPORT
SN...BUT H85 TEMPS FALLING TO -10C TO -14C BY 12Z MON OVER THE W WL
BE SUFFICIENTLY COLD TO BRING AT LEAST SCT LK EFFECT SHSN TO AREAS
FAVORED BY FCST W WIND DESPITE SLIGHTLY LLVL ACYC FLOW. ANY SN/SLEET
ACCUM SHOULD BE UNDER AN INCH. SHARP LLVL COOLING ASSOCIATED WITH
H85-7 FGEN MAX SLOPED FAIRLY FAR TO THE W OF THE SFC FNT MAY CREATE
ELEVATED WARM LYR/POTENTIAL FOR SLEET AS WELL AS SN TO THE CNTRL ZNS
ON THE WRN EDGE OF THE LARGER SYNOPTIC SCALE PCPN AREA TO THE E. THE
E SHOULD REMAIN WARM ENUF FOR MAINLY RA GIVEN FCST H85 TEMPS/H100-85
THKNS.
.LONG TERM...(MONDAY THROUGH SATURDAY)
ISSUED AT 533 AM EST SUN NOV 11 2012
MAIN FOCUS INITIALLY IN LONG TERM IS DEEP/COLD/MOIST LOW-MID LEVEL
TROUGH EXTENDING FROM ONTARIO TO THE MIDDLE MISSISSIPPI RIVER
VALLEY ON MONDAY. SFC COLD FRONT WILL BE THROUGH UPR MICHIGAN BY 12Z
MONDAY. KEPT HIGHER POPS OVER FAR EAST FOR MAINLY SNOW THROUGH MID
MORNING...BUT WILL BE DRYING OUT ELSEWHERE OVER THE EAST IN WAKE OF
THE FRONT.
ALREADY PLENTY COLD ENOUGH AT H85 /H85 TEMPS AROUND -10C/ TO SUPPORT
LK EFFECT OFF LK SUPERIOR TO START THE DAY GIVEN WATER TEMPS AROUND
+8C. OVER-WATER INSTABILITY RAMPS UP FURTHER THROUGH THE DAY WITH
DELTA T/S WELL OVER 20C BY EVENING IN A MOIST ENVIRONMENT TO H7. NOT
THE USUALLY TYPICAL REALLY COLD BUT REALLY DRY AIRMASS FOR THE LK
EFFECT TO WORK ON...AT LEAST NOT UNTIL LATER MONDAY NIGHT WITH
ARRIVAL OF DRIER AIR AOA H85. NAM/GFS SOUNDINGS INDICATE INVERSION
HEIGHTS OR AT LEAST LAKE EQUILIBRIUM LEVELS TOPPING OUT AROUND 10KFT
AND LOW-LEVEL LAPSE RATES EXCEEDING 9C/KM. SINCE IT IS CHILLY AT SFC
AND ALOFT...MUCH OF THE LAKE CONVECTIVE LAYER WILL BE WITHIN HEART
OF DENDRITIC GROWTH ZONE...BOOSTING SLR/S AND ULTIMATELY SNOWFALL
TOTALS.
PRIMARY QUESTION IS HOW QUICKLY ON MONDAY WILL SIGNIFICANT LK EFFECT
SNOW SHOWERS DEVELOP AND WHERE WILL HEAVIER SNOWS OCCUR THROUGH
MONDAY NIGHT. LOW-LEVEL WINDS IN WAKE OF COLD FRONT ARE MORE FROM
WSW INITIALLY ON MONDAY MORNING WHICH FAVORS MAJORITY OF SNOW
IMPACTING MAINLY NORTHERN PORTIONS OF KEWEENAW PENINSULA. SFC WINDS
GRADUALLY TURN MORE NORTHWEST ON MONDAY EVENING AS SFC TROUGH WORKS
ACROSS LK SUPERIOR AND NORTHERN UPR MICHIGAN. SOUNDINGS INDICATE
THAT EVEN AS SUB H85 WINDS ARE MOSTLY FROM THE WSW MUCH OF MONDAY
THE WINDS FROM H8-H7 SHIFT TO NW DURING THE AFTN OVER WESTERN UPR
MICHIGAN. MAY SEE SITUATION WHERE MORE OF A WIDESPREAD SNOW ENVELOPS
MOST OF NW/W UPR MICHIGAN BY MID AFTN DUE TO COOL/MOIST PROFILE
UPWARDS OF H7. MEANWHILE...BLYR WINDS WOULD FAVOR CONVERGENCE BAND
OF HEAVIER SNOW TO SET UP SOMEWHERE ALONG WEST SIDE OF KEWEENAW THEN
GRADUALLY SINKING SOUTHWARD LATE IN THE DAY INTO THE EVENING WITH
THE SFC WIND SHIFT. ALL FACTORS ARE FAVORABLE FOR INTENSE SNOW RATES
AFTN-EVENING WHERE THE BAND DEVELOPS. INSTABILITY PARAMETERS AND
LOCAL GUIDANCE ALONG WITH LAKE SNOW PARAMETER DEVELOPED BY NWS
OFFICE IN GAYLORD MI ALL POINT TO HEAVY SNOWFALL RATES /AT LEAST 1"
PER HR/ LATER MONDAY AFTN AND MONDAY EVENING OVR NW UPR MICHIGAN.
CURRENTLY HAVE POTENTIAL FOR SNOW MENTIONED IN HAZARDOUS WEATHER
OUTLOOK FOR NW CWA. CANNOT FORGET THE FAR NORTHEAST CWA AS WELL WITH
WINDS SHIFTING ONSHORE AND LEADING TO POTENTIAL OF DOMINANT BAND OF
SNOW IMPACTING THOSE AREAS AS WELL...MAINLY EAST OF P53 INTO
NORTHERN LUCE COUNTY. AS MENTIONED IN PREVIOUS DISCUSSION...MORE
RESIDENCE TIME OVER THE WARMER LAKE WATERS AND A BIT MORE WARMER
AIRMASS OVERALL MAY ACT TO LIMIT SNOW AMOUNTS COMPARED TO WHAT IS
EXPECTED TO OCCUR OVER NW UPR MICHIGAN. SOME SNOW ACCUMULATIONS ARE
LIKELY THOUGH.
LATER MONDAY NIGHT AND FOR SURE INTO MID MORNING TUESDAY...WILL SEE
LK EFFECT DIMINISH SIGNIFICANTLY MAINLY DUE TO DEPARTURE OF MOISTURE
ABOVE H85 AND AS STEADILY WARMING TEMPS AT TOP OF 5KFT INVERSION.
MOISTURE DECREASES DRAMATICALLY BY 12Z TUESDAY...ESPECIALLY IN THE
WEST. COULD EVEN SEE SKIES BECOME MOSTLY CLEAR OVER FAR SOUTH AWAY
FROM EFFECTS OFF THE LAKE. IN ANY CASE...WHAT LAKE EFFECT IS LEFT
AT THAT TIME WILL BE SHADOW OF WHAT WILL HAVE JUST OCCURRED 12 HR
PREVIOUSLY. NO REAL CHANGES TO POPS FOR MONDAY THROUGH MONDAY NIGHT
AND INTO TUESDAY...JUST SOME TWEAKING TO MATCH LATEST MODEL TRENDS.
DID INCREASE SNOW AMOUNTS SOME OVER NORTHWEST GIVEN INCREASING
CONFIDENCE IN OVERALL SCENARIO. CURRENTLY FORECASTED SNOW AMOUNTS
SUPPORT ADVISORY HEADLINES EVENTUALLY. THAT SAID...CERTAINLY
POSSIBLE THAT AT LEAST ISOLD LOCATIONS FROM ONTONAGON THROUGH
HOUGHTON AND KEWEENAW COUTNIES MAY SEE WARNING CRITERIA SNOWFALL
FROM THIS EARLY SEASON LAKE SNOW EVENT. ON A SIDE NOTE...WINDS IN
THE STRONGER CONVERGENCE AREAS ACROSS KEWEENAW MAY TOP OUT 30-40 MPH
ON MONDAY AND MONDAY EVENING. SO IN ADDITION TO THE HEAVY SNOW COULD
ALSO SEE STRONG/GUSTY WINDS WITHIN THOSE HEAVIER SNOW SQUALLS.
PLAN TO MENTION THIS IN THE HAZARDOUS WEATHER OUTLOOK.
REST OF LONG TERM...PRETTY QUIET OVERALL AS PACIFIC FLOW ALOFT WILL
BE IN CONTROL. SFC HIGH BUILDS IN LATER TUESDAY AND MOVES EAST ON
WEDNESDAY. LOWERED MINS ON TUESDAY NIGHT WITH COLD AIRMASS IN PLACE.
MID CLOUDS INCREASE LATE BUT SEEMED REASONABLE TO START THE NIGHT
TEMPS COULD FALL OFF INTO THE TEENS BEFORE BECOMING MORE STEADY LATE.
WEDNESDAY MAY END UP FAIRLY CLOUDY...BUT REALLY WHAT ELSE IS NEW
LATELY. A LOT OF MID CLOUDS SHOW UP IN THE MODELS...BUT DRY SUB H85
AIR DUE TO LINGERING AFFECTS OF THE SFC HIGH AND NOT VERY STRONG
LIFT ALOFT RESULT IN KEEPING DRY FORECAST GOING FOR CWA. WEAK WARM
AIR ADVECTION AND ADDITIONAL MOISTURE ADVECTION AHEAD OF SFC TROUGH
MOVING ACROSS ONTARIO BY THURSDAY MORNING COULD PROVIDE CHANCE FOR
SOME LGT SNOW/FLURRIES ON WEDNESDAY NIGHT. DRY FORECAST TO CLOSE THE
WEEK AND THROUGH NEXT SATURDAY WITH LACK OF SYSTEMS MOVING THROUGH
IN THE WESTERLY FLOW. SW FLOW IN LOWER LEVELS FRIDAY/SATURDAY MAY
ALLOW FOR TEMPS TO PUSH SLIGHTY ABOVE NORMAL.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1224 AM EST SUN NOV 11 2012
SHOWERS LIFTING OVER THE AREA WITH PASSAGE OF WARM FRONT COMBINED
WITH MOIST UPSLOPE E-SE FLOW SHOULD MAINTAIN CONDITIONS AT AIRFIELD
LANDING MINS AT KCMX AND ALT LANDING MINS AT KSAW THROUGH AT LEAST
08Z. AT KIWD...LOW STRATUS HAS LIFTED OUT TEMPORARILY BUT SCT SHRA
AND ISOLD TSRA COULD AFFECT AIRPORT INTO THE OVERNIGHT. AS WINDS
SHIFT SRLY LATE TONIGHT...LOOK FOR CONDITIONS TO IMPROVE TO LOW MVFR
AT KSAW AND KCMX. AS THE COLD FRONT ADVANCES FROM THE PLAINS...SHRA
WILL ARRIVE AT KIWD AND KCMX BY LATE SUNDAY MORNING AND AT KSAW BY
MID-LATE AFTERNOON SENDING CONDITIONS BACK DOWN TO IFR. SOME MID-LVL
INSTABILITY WILL ALSO WARRANT A MENTION OF VCTS AT ALL SITES AHEAD
OF THE COLD FRONT ARRIVAL. WINDS SHIFTING TO AN ONSHORE/UPSLOPE WRLY
DIRECTION BEHIND THE FRONT MAY ALSO LOWER VSBYS/CIGS DOWN NEAR ALT
LANDING MINS AT KIWD AND KCMX SUN AFTERNOON. COLD ADVECTION WILL
CHANGE PCPN OVER TO SNOW BY EARLY EVENING AT KIWD AND BY LATE
EVENING AT KCMX.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 533 AM EST SUN NOV 11 2012
EXPECT S WINDS UP TO 25 TO 30 KTS...STRONGEST OVER THE E HALF UNDER
TIGHTER PRES GRADIENT...IN ADVANCE OF AN APPROACHING COLD FRONT TO
SHIFT TO THE W FOLLOWING THE COLD FROPA OVER THE W THIS AFTERNOON AND
THEN OVER THE CENTRAL AND E TONIGHT AS MUCH COLDER AIR FLOWS OVER THE
RELATIVELY WARM LAKE WATERS AND ENHANCES MIXING OF STRONGER WINDS TO
THE SURFACE.
PRESSURE GRADIENT STAYS TIGHT ON MONDAY WITH WEST WINDS UP TO 30 KTS
AND OCCASIONAL GALE GUSTS TO 35 KTS. PRESSURE GRADIENT SLACKENS
MONDAY NIGHT AND TUESDAY WITH WINDS DIMINISHING BLO 25 KTS. A LOW
PRESSURE TROUGH WILL PUSH ACROSS NORTHERN ONTARIO ON THURSDAY. SOUTH
WINDS AHEAD OF THE TROUGH COULD REACH 25 KTS OVER EASTERN SECTIONS
OF LK SUPERIOR WEDNESDAY AND WEDNESDAY NIGHT. WINDS TO FINISH UP THE
WEEK WILL BE BLO 20 KTS AS PRESSURE GRADIENT DIMINISHES.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...VOSS
MARINE...KC/JLA
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
328 AM EST SUN NOV 11 2012
.SYNOPSIS...
ISSUED AT 328 AM EST SUN NOV 11 2012
STRONG SOUTH WINDS WILL DEVELOP ACROSS THE REGION TODAY AHEAD OF A
STRONG COLD FRONT. A PUSH OF WARM AIR WILL SEND TEMPERATURES INTO
THE UPPER 60S A MANY LOCATIONS THIS AFTERNOON. SHOWERS WILL DEVELOP
LATE IN THE DAY AND CONTINUE TONIGHT AS THE FRONT MOVES ACROSS THE
AREA. MUCH COLDER AIR ALONG WITH RAIN AND SNOW SHOWERS WILL MOVE
INTO WEST MICHIGAN MONDAY. HIGH TEMPERATURES WILL SLOWLY FALL DURING
THE DAY AND ONLY REACH AROUND 40 DEGREES TUESDAY. MAINLY DRY WEATHER
IS EXPECTED AFTER MONDAY WITH SLOWLY WARMING TEMPERATURES.
&&
.SHORT TERM...(TODAY THROUGH TUESDAY)
ISSUED AT 328 AM EST SUN NOV 11 2012
FORECAST CONCERNS DEAL WITH THE WIND POTENTIAL TODAY AND PCPN TRENDS
TONIGHT/MONDAY.
THE GOING FORECAST IS LARGELY ON TRACK. HOWEVER...WINDS APPEAR A BIT
STRONGER ACROSS THE WRN CWA AS THE GRADIENT TIGHTENS AHEAD OF THE
COLD FRONT. AS SUCH WE ISSUED A WIND ADVISORY FOR THE WRN 1/2 OF THE
CWA. WINDS ARE ALREADY GUSTING TO 36 KTS AT KMKG AND WILL LIKELY
INCREASE A BIT MORE AS THE SUN RISES AND BETTER MIXING OCCURS.
STRONG 65KT LLJ MOVES OVER THE WRN CWA LATE THIS AFTERNOON.
LATEST HRRR HAS A PRETTY GOOD HANDLE ON THE SHOWERS MOVING ACROSS
NRN IL/WISCONSIN. THESE ARE AHEAD OF THE COLD FRONT AND DISSIPATE
SOMEWHAT AS THEY MOVE EWD THIS AFTERNOON. AS A RESULT...WE
ANTICIPATE A DRY DAY. ABUNDANT MID CLOUD WILL BE PRESENT AND THIS
WILL LIMIT MIXING A BIT BUT NOT ENOUGH TO PREVENT SUSTAINED 25 TO 30
MPH WINDS. FROPA IS ON TRACK FOR MIDNIGHT-4AM TIME FRAME. TEMPS WILL
SLOWLY FALL MONDAY AS H8 TEMPS FALL TO -12C. RAIN WILL MIX WITH SNOW
AFTER FROPA THEN BECOME SHSN AS THE THERMAL PROFILE QUICKLY FALLS
BELOW 0C. NOT LOOKING FOR ACCUMS AT THIS POINT. THOUGH IT/S POSSIBLE
A FEW HIGHER ELEVATIONS ACROSS THE NRN CWA COULD SEE A COUPLE OF
TENTHS.
TUESDAY LOOKS DRY BUT CHILLY WITH HIGHS AROUND 40.
.LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY)
ISSUED AT 328 AM EST SUN NOV 11 2012
FOR THE EXTENDED PERIOD...THE CORE OF THE ARCTIC AIR REMAINS WELL
NORTH OF THE REGION. ONE OF THE MAIN REASONS FOR THIS IS THE ZONAL
MID LEVEL FLOW THAT SETS UP ACROSS NORTH AMERICA FOR THE PERIOD.
HERE IN MI...WE WILL SEE ONLY A WEAKENING COLD FRONT ARRIVING THU.
IF THERE IS ANY PRECIPITATION WITH THIS SHALLOW FEATURE...IT WILL BE
LIMITED AS VERY LITTLE MOISTURE AND LIFT WILL BE IN PLACE.
TEMPERATURES AT 850 MB CLIMB THU INTO SAT...SO WE WILL LIKELY SEE A
GENERAL WARMING TREND. ALTHOUGH...GIVEN THE MID LEVEL
FLOW...PACIFIC MOISTURE COULD CAUSE PERIODS OF CLOUDS THAT WOULD
POTENTIALLY LIMIT THE DAYTIME MIXING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT)
ISSUED AT 1136 PM EST SAT NOV 10 2012
I EXPECT VFR CONDITIONS TO PREVAIL THROUGH EARLY EVENING SUNDAY AS
A STRONG SOUTHERLY FLOW AHEAD OF THE COLD FRONT WILL CONTINUE TO
BRING LOW TO MID LEVEL DRY AIR NORTH. IT WILL BE WINDY TOO.
SURFACE WINDS OF 15 KNOTS WITH GUSTS TO 25 KNOTS ARE EXPECTED
TONIGHT BUT VAD WIND PROFILE IS SHOWING 35 KNOTS AT 2000 FT AND 50
KNOTS AT 3000 FT AGL. I CONTINUED THE LOW LEVEL WIND SHEAR IN THE
TAFS UNTIL THE SUN ALLOWS MIXING OF THE BOUNDARY LAYER... AROUND
15Z. THEN EXPECT 20-30 KNOT WINDS WITH HIGHER GUSTS.
I DO NOT EXPECT THE SHOWERS OVER WISCONSIN LATE THIS EVENING TO
IMPACT THE TAF SITES DUE TO THE MID LEVEL DRY AIR (RAP SOUNDING
SHOW VERY DRY AIR BELOW 15000 FT THROUGH 12Z). THE LINE OF
CONVECTION WITH THE COLD FRONT SHOULD NOT REACH THE TAF SITES
UNTIL 03Z MONDAY NEAR MKG AND WELL AFTER 06Z ON MONDAY AT JXN.
&&
.MARINE...
ISSUED AT 328 AM EST SUN NOV 11 2012
GIVEN THAT WINDS ALONG THE LAKESHORE ARE ALREADY GUSTING NEAR
35KTS...DECIDED TO RUN WITH THE GALE WARNING NOW AND DISCONTINUE THE
SCA. GALES TO 40KTS EXPECTED TODAY WILL BUILD WAVES TO 5 TO 8 FEET.
THE CORE OF THE STRONGER WINDS WILL DIMINISH AFTER 06Z TONIGHT.
&&
.HYDROLOGY...
ISSUED AT 328 AM EST SUN NOV 11 2012
A THIRD OF AN INCH OF PCPN IS EXPECTED AHEAD OF THE COLD FRONT
TONIGHT. THIS SHOULDN/T RESULT IN FLOODING.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...WIND ADVISORY FROM 7 AM THIS MORNING TO 3 AM EST MONDAY FOR
MIZ037-038-043-044-050-056-057-064-065-071-072.
LM...GALE WARNING UNTIL 10 PM EST THIS EVENING FOR LMZ844>849.
&&
$$
SYNOPSIS...93
SHORT TERM...93
LONG TERM...MJS
AVIATION...WDM
HYDROLOGY...93
MARINE...93
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
347 PM CST SUN NOV 11 2012
.DISCUSSION...
Short Range (Tonight through Tuesday):
Impressive upper trough moving east through the Plains late this
afternoon. Best lift/sensible weather occurring well downstream over
the mid MO River Valley where mixed precipitation is falling. The
combination of significant cold air advection through the entire
column, elevated frontogenesis and increasing upper level jet
dynamics has allowed sleet to form on the western edge of the rain
shield. Short range models, HRRR, RAP and NAM all clear out the
precipitation over the eastern counties by 03Z. Have slowed down the
end of the precipitation slightly due to the positive tilt of the
upper trough and the associated strong upper level jet dynamics.
Weather looking pretty tranquil after the upper trough axis passes
through the CWA early Monday. Strong subsidence on the back side of
the trough should greatly limit the effects of a secondary vorticity
lobe sliding through eastern NE/KS during the day. Although the
models show warm air advection occurring on Monday its effects will
be muted due to such a cold start to the day.
A semi-zonal flow pattern will ensue over the central U.S. by Monday
night and continue into mid week. A fast moving shortwave embedded
within this flow will streak through KS/NE/IA/MO on Tuesday,
However, moisture will be limited, especially within the boundary
layer so should only see a modest pick up in clouds with moderate
warm air advection resulting in seasonally average temperatures.
MJ
Medium Range (Wednesday through Sunday):
A few troughs may drop through primarily zonal flow during the
latter half of the week; however, with dry surface high pressure
sitting over the southeastern U.S, precipitation chances look very
low through at least Saturday. Temperatures should hover around to a
few degrees below normal in the absence of any amplified troughing
or ridging through the Plains, with highs mainly in the 50`s and
lows in the 30`s.
As the surface high weakens and gradually slides eastward Saturday,
both the EC and GFS bringing a shortwave trough into Nebraska and
eastern Kansas, potentially fueling widespread but light, scattered
precipitation especially across the western half of the CWA. Aloft,
temperatures look warm enough for a liquid precipitation type across
the region, especially without any deep cold air poised to filter in
behind the system.
Laflin
&&
.AVIATION...
For the 18Z TAFS...The back edge of the precipitation shield, which
has some sleet and snow mixed in with the rain, has moved east of
KSTJ and will likely be east of KMCI at the the start of the
forecast period. Will mention mix of rain/sleet for KMKC for another
hr. Otherwise, low MVFR cigs for most of the afternoon with
improvement to high end MVFR by late afternoon. Clearing line should
reach the terminals early this evening. Gusty northwest winds will
drop off by around 00z with winds gradually backing to the southwest
overnight.
MJ
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
WFO EAX
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1251 AM EST SUN NOV 11 2012
.SYNOPSIS...
A WARM FRONT WILL MOVE FROM SOUTHWEST TO NORTHEAST ACROSS OUR AREA
TONIGHT. THIS FRONT WILL BRING CLOUDS AND LIGHT PRECIPITATION TO
THE AREA...MAINLY AFTER MIDNIGHT. TEMPERATURES WILL BE SUCH THAT
LIGHT MIXED PRECIPITATION IS POSSIBLE...BUT NO ICE OR SNOW
ACCUMULATIONS ARE EXPECTED. THE WARM FRONT WILL BE NORTH OF THE
AREA ON SUNDAY AND A WARMING TREND IS EXPECTED WITH HIGH
TEMPERATURES BY MONDAY ABOUT 15 DEGREES ABOVE NORMAL.
&&
.NEAR TERM /UNTIL 7 AM THIS MORNING/...
AS OF 1215 AM EST SUNDAY...PREVIOUS UPDATE HAS HANDLE OF CURRENT
CONVECTION APPROACHING LAKE ONTARIO. DECENT SHOWWALTER AND MOST
UNSTABLE CAPE IN CLOSEST PROXIMITY TO H9 FNT AND STG LLVL JET.
HWVR...THAT SHLD STAY S OF FA AND WEAKEN AS IT MOVES INTO
STABLE...COLDER AIRMASS.
PREVIOUS DISCUSSION...MODEST UPDATES TO SKY COVER AND POPS
THROUGH THE OVERNIGHT HOURS THROUGH MID-MORNING SUNDAY AS OF 930
PM TO ACCT FOR CURRENT TRENDS AND LATEST HRRR DATA. ALL AREAS HAVE
ESSENTIALLY TRENDED CLOUDY AND SHOULD REMAIN SO THROUGH THE
REMAINDER OF THE NIGHT AS WARM FRONT NOW APPROACHING QUICKLY FROM
THE WEST/SOUTHWEST. THUS MINIMUM TEMPERATURES HAVE BEEN REACHED IN
MOST LOCALES WITH STEADY OR SLOWLY RISING VALUES EXPECTED FROM
HERE ON OUT. BLOSSOMING ELEVATED CONVECTION ACROSS SW ONTARIO/LK
HURON INITIALIZED FAIRLY GOOD BY 21-00Z HRRR RUNS AND CORFIDI
VECTOR/STREAMLINE ANALYSIS SUGGESTS THIS ACTIVITY SHOULD STREAK
EAST...ALBEIT IN WEAKENED FORM INTO OUR NRN COUNTIES LATER TONIGHT
INTO TOMORROW MORNING. NO THUNDER AS ELEV INSTABILITY CURRENTLY
DRIVING GREAT LAKES ACTIVITY WILL ERODE BY THE TIME IT GETS HERE.
NONETHELESS HAVE RAISED POPS UPWARD BY 10/20% ACROSS NRN NY AND
LEAST BROUGHT CHC POPS INTO NRN VT ACCORDINGLY. QPF STILL TO
REMAIN LIGHT...BUT COULD SEE SLIGHTLY HIGHER AMTS TO NEAR
0.10-0.15 INCHES ACROSS NRN NY COUNTIES. P-TYPE MAINLY LIQUID AS
WARMER AIR ALOFT STREAMS QUICKLY NORTHEAST...THOUGH A BRIEF PERIOD
OF VERY LIGHT FZRA POSSIBLE ACROSS FAR NERN VT AFTER 08Z. HAVE A
GOOD NIGHT.
&&
.SHORT TERM /7 AM THIS MORNING THROUGH MONDAY NIGHT/...
AS OF 334 PM EST SATURDAY...WE COULD SEE SOME LIGHT MIXED
PRECIPITATION OVER PARTS OF THE NORTHEAST KINGDOM EARLY SUNDAY
MORNING...BUT WARM FRONT QUICKLY LIFTS NORTH OF THE AREA AS UPPER
RIDGE BEGINS TO AMPLIFY OVER THE AREA. BY MIDDAY WE SHOULD SEE DRY
WEATHER AND PLENTY OF SUNSHINE WITH THE AREA IN THE WARM SECTOR.
TEMPERATURES SHOULD ALSO WARM INTO THE 50S MOST LOCATIONS.
PRESSURE GRADIENT WILL STRENGTHEN OVER AREA IN THE AFTERNOON...SO
LOOKING AT SOME GUSTS FROM THE SOUTH AND SOUTHWEST LATE IN THE
DAY...20 TO 30 MPH. PRESSURE GRADIENT STRENGTHENS EVEN MORE ON
MONDAY AS LARGE UPPER TROUGH MOVES TOWARD THE REGION. LOOKING AT
BREEZY TO WINDY CONDITIONS MONDAY AFTERNOON AND EVENING. WARMEST
AIR IN THE LOWER LEVELS MOVES INTO THE REGION WITH HIGHS IN THE
60S...BUT WITH THAT MUCH WIND...IT WILL NOT FEEL THAT WARM.
NEVERTHELESS...THESE TEMPERATURES ARE ABOUT 15 DEGREES ABOVE
NORMAL FOR THIS TIME OF YEAR. THE HIGHER AMPLITUDE UPPER PATTERN
SUGGESTS THAT PRECIPITATION WILL BE CLOSELY TIED TO THE UPPER
TROUGH AXIS AND SURFACE COLD FRONT. AS A RESULT...PRECIPITATION
WILL BE SLOW TO PUSH IN AND EXPECT A DRY DAY ON MONDAY AND INTO
THE FIRST PART OF MONDAY EVENING. RAIN SHOULD THEN SPREAD INTO THE
REGION LATER MONDAY NIGHT...ESPECIALLY AFTER MIDNIGHT. GOING
FORECAST HAS LIKELY TO CATEGORICAL PRECIPITATION CHANCES DURING
THAT TIME PERIOD AND HAVE KEPT THAT THE SAME.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 334 PM EST SATURDAY...THE MAIN WEATHER FEATURE OF INTEREST DURING
THE EXTENDED IS THE COLD FRONT FROM THE PREVIOUS PERIOD. THE
FRONT WILL CONTINUE PROGRESSING EASTWARD ACROSS THE NORTH COUNTRY
TUESDAY. THE PRESENCE OF A LARGE UPPER RIDGE AHEAD OF THE FRONT
AND POTENTIAL FOR NEARLY BOUNDARY-PARALLEL UPPER FLOW SUGGESTS THE
FRONT MAY BE SLOW TO MOVE EASTWARD. STRONG POST-FRONTAL 850/925 MB
COLD ADVECTION WITH 850 MB TEMPERATURES FALLING FROM 10C TO 0-2C
DURING THE AFTERNOON. WOULD EXPECT A NON-DIURNAL TEMPERATURE RANGE
ON TUESDAY WITH HIGHS IN THE 40S TO AROUND 50 LIKELY BEING REACHED
LATE MORNING/EARLY AFTERNOON. PRECIPITATION PROBABILITIES RANGE
FROM LIKELY AHEAD OF THE FRONT ON TUESDAY BEFORE TAPERING QUICKLY
WITH WESTWARD EXTENT. WHILE RAIN IS EXPECTED AHEAD OF THE
FRONT...ANY LIGHT PRECIPITATION THAT OCCURS BEHIND THE FRONT COULD
MIX TO SNOW SHOWERS IN THE NORTHERN ADIRONDACKS AS THERMAL
PROFILES COOL. THE FRONT COULD BE A LITTLE SLOW TO MOVE OUT OF
VERMONT ON TUESDAY NIGHT AS UPPER FLOW BECOMES MORE BOUNDARY-
PARALLEL...SO HAVE CARRIED SLIGHT CHANCE TO CHANCE PRECIPITATION
PROBABILITIES INTO TUESDAY NIGHT.
THE REST OF THE EXTENDED IS RATHER BENIGN AS SFC HIGH PRESSURE
BECOMES ESTABLISHED NORTH OF THE REGION. SEVERAL WEAK MID-LEVEL
SHORTWAVE TROUGHS TRAVERSE THE REGION LATE IN THE WEEK...THOUGH THE
TROUGHS WILL HAVE LIMITED MOISTURE TO WORK WITH. SO WHILE THE
TROUGHS MAY PRODUCE SOME CLOUDS HAVE KEPT THE FORECAST DRY. 850 MB
TEMPERATURES OF -3 TO -6C WEDNESDAY AND THURSDAY RESULT IN HIGHS IN
THE 40S AND LOWS IN THE 20S BOTH DAYS. MODERATING TEMPERATURES ARE
EXPECTED BY LATE WEEK AS 850MB TEMPERATURES RECOVER TO AROUND
0C.
&&
.AVIATION /06Z SUNDAY THROUGH THURSDAY/...
THROUGH 06Z MONDAY...VFR CONDITIONS EXPECTED THROUGH THE PERIOD. A
WARM FRONT WILL PASS ACROSS THE REGION OVERNIGHT THROUGH SUNDAY
MORNING ACCOMPANIED BY CLOUDS AND SOME VERY LIGHT PRECIPITATION.
HOWEVER...CEILINGS AND VISIBILITIES ARE EXPECTED TO REMAIN VFR AT
ALL TAF SITES. ANY LIGHT PRECIPITATION WHICH DOES OCCUR WILL BE
MAINLY IN THE FORM OF RAIN OR DRIZZLE...HOWEVER A BRIEF PERIOD OF
VERY LIGHT FREEZING RAIN OR SLEET IS POSSIBLE AT SLK/MPV BEFORE
TEMPERATURES RISE OVERNIGHT. GREATEST CHANCE OF PRECIPITATION WILL
OCCUR 08Z-14Z...FOLLOWED BY DRYING WITH CLEARING SKIES THIS
AFTERNOON. SOUTH WINDS WILL BE INCREASING LATER TONIGHT AND INTO
SUNDAY...WITH SOME GUSTS 15-25 KNOTS BY THE AFTERNOON.
OUTLOOK 06Z MONDAY THROUGH THURSDAY...
06Z MONDAY THROUGH 00Z TUESDAY...VFR UNDER RIDGE OF HIGH PRESSURE.
GUSTY SOUTH WINDS LIKELY...ESPECIALLY MONDAY AFTERNOON.
00Z TUESDAY THROUGH 00Z WEDNESDAY...PERIODS OF MVFR/IFR IN RAIN
SHOWERS AS A COLD FRONT MOVES ACROSS THE REGION.
00Z WEDNESDAY ONWARD...VFR UNDER BUILDING HIGH PRESSURE.
&&
.CLIMATE...
RECORD MAXIMUM TEMPERATURES FOR MONDAY NOVEMBER 12TH:
BURLINGTON - 66 IN 1982
MONTPELIER - 62 IN 1982
ST. JOHNSBURY - 65 IN 1911
MASSENA - 70 IN 1982
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...EVENSON
NEAR TERM...JMG/SLW
SHORT TERM...EVENSON
LONG TERM...LOCONTO
AVIATION...RJS
CLIMATE...
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1218 AM EST SUN NOV 11 2012
.SYNOPSIS...
A WARM FRONT WILL MOVE FROM SOUTHWEST TO NORTHEAST ACROSS OUR AREA
TONIGHT. THIS FRONT WILL BRING CLOUDS AND LIGHT PRECIPITATION TO
THE AREA...MAINLY AFTER MIDNIGHT. TEMPERATURES WILL BE SUCH THAT
LIGHT MIXED PRECIPITATION IS POSSIBLE...BUT NO ICE OR SNOW
ACCUMULATIONS ARE EXPECTED. THE WARM FRONT WILL BE NORTH OF THE
AREA ON SUNDAY AND A WARMING TREND IS EXPECTED WITH HIGH
TEMPERATURES BY MONDAY ABOUT 15 DEGREES ABOVE NORMAL.
&&
.NEAR TERM /UNTIL 7 AM THIS MORNING/...
AS OF 1215 AM EST SUNDAY...PREVIOUS UPDATE HAS HANDLE OF CURRENT
CONVECTION APPROACHING LAKE ONTARIO. DECENT SHOWWALTER AND MOST
UNSTABLE CAPE IN CLOSEST PROXIMITY TO H9 FNT AND STG LLVL JET.
HWVR...THAT SHLD STAY S OF FA AND WEAKEN AS IT MOVES INTO
STABLE...COLDER AIRMASS.
PREVIOUS DISCUSSION...MODEST UPDATES TO SKY COVER AND POPS
THROUGH THE OVERNIGHT HOURS THROUGH MID-MORNING SUNDAY AS OF 930
PM TO ACCT FOR CURRENT TRENDS AND LATEST HRRR DATA. ALL AREAS HAVE
ESSENTIALLY TRENDED CLOUDY AND SHOULD REMAIN SO THROUGH THE
REMAINDER OF THE NIGHT AS WARM FRONT NOW APPROACHING QUICKLY FROM
THE WEST/SOUTHWEST. THUS MINIMUM TEMPERATURES HAVE BEEN REACHED IN
MOST LOCALES WITH STEADY OR SLOWLY RISING VALUES EXPECTED FROM
HERE ON OUT. BLOSSOMING ELEVATED CONVECTION ACROSS SW ONTARIO/LK
HURON INITIALIZED FAIRLY GOOD BY 21-00Z HRRR RUNS AND CORFIDI
VECTOR/STREAMLINE ANALYSIS SUGGESTS THIS ACTIVITY SHOULD STREAK
EAST...ALBEIT IN WEAKENED FORM INTO OUR NRN COUNTIES LATER TONIGHT
INTO TOMORROW MORNING. NO THUNDER AS ELEV INSTABILITY CURRENTLY
DRIVING GREAT LAKES ACTIVITY WILL ERODE BY THE TIME IT GETS HERE.
NONETHELESS HAVE RAISED POPS UPWARD BY 10/20% ACROSS NRN NY AND
LEAST BROUGHT CHC POPS INTO NRN VT ACCORDINGLY. QPF STILL TO
REMAIN LIGHT...BUT COULD SEE SLIGHTLY HIGHER AMTS TO NEAR
0.10-0.15 INCHES ACROSS NRN NY COUNTIES. P-TYPE MAINLY LIQUID AS
WARMER AIR ALOFT STREAMS QUICKLY NORTHEAST...THOUGH A BRIEF PERIOD
OF VERY LIGHT FZRA POSSIBLE ACROSS FAR NERN VT AFTER 08Z. HAVE A
GOOD NIGHT.
&&
.SHORT TERM /7 AM THIS MORNING THROUGH MONDAY NIGHT/...
AS OF 334 PM EST SATURDAY...WE COULD SEE SOME LIGHT MIXED
PRECIPITATION OVER PARTS OF THE NORTHEAST KINGDOM EARLY SUNDAY
MORNING...BUT WARM FRONT QUICKLY LIFTS NORTH OF THE AREA AS UPPER
RIDGE BEGINS TO AMPLIFY OVER THE AREA. BY MIDDAY WE SHOULD SEE DRY
WEATHER AND PLENTY OF SUNSHINE WITH THE AREA IN THE WARM SECTOR.
TEMPERATURES SHOULD ALSO WARM INTO THE 50S MOST LOCATIONS.
PRESSURE GRADIENT WILL STRENGTHEN OVER AREA IN THE AFTERNOON...SO
LOOKING AT SOME GUSTS FROM THE SOUTH AND SOUTHWEST LATE IN THE
DAY...20 TO 30 MPH. PRESSURE GRADIENT STRENGTHENS EVEN MORE ON
MONDAY AS LARGE UPPER TROUGH MOVES TOWARD THE REGION. LOOKING AT
BREEZY TO WINDY CONDITIONS MONDAY AFTERNOON AND EVENING. WARMEST
AIR IN THE LOWER LEVELS MOVES INTO THE REGION WITH HIGHS IN THE
60S...BUT WITH THAT MUCH WIND...IT WILL NOT FEEL THAT WARM.
NEVERTHELESS...THESE TEMPERATURES ARE ABOUT 15 DEGREES ABOVE
NORMAL FOR THIS TIME OF YEAR. THE HIGHER AMPLITUDE UPPER PATTERN
SUGGESTS THAT PRECIPITATION WILL BE CLOSELY TIED TO THE UPPER
TROUGH AXIS AND SURFACE COLD FRONT. AS A RESULT...PRECIPITATION
WILL BE SLOW TO PUSH IN AND EXPECT A DRY DAY ON MONDAY AND INTO
THE FIRST PART OF MONDAY EVENING. RAIN SHOULD THEN SPREAD INTO THE
REGION LATER MONDAY NIGHT...ESPECIALLY AFTER MIDNIGHT. GOING
FORECAST HAS LIKELY TO CATEGORICAL PRECIPITATION CHANCES DURING
THAT TIME PERIOD AND HAVE KEPT THAT THE SAME.
&&
.LONG TERM /TUESDAY THROUGH SATURDAY/...
AS OF 334 PM EST SATURDAY...THE MAIN WEATHER FEATURE OF INTEREST DURING
THE EXTENDED IS THE COLD FRONT FROM THE PREVIOUS PERIOD. THE
FRONT WILL CONTINUE PROGRESSING EASTWARD ACROSS THE NORTH COUNTRY
TUESDAY. THE PRESENCE OF A LARGE UPPER RIDGE AHEAD OF THE FRONT
AND POTENTIAL FOR NEARLY BOUNDARY-PARALLEL UPPER FLOW SUGGESTS THE
FRONT MAY BE SLOW TO MOVE EASTWARD. STRONG POST-FRONTAL 850/925 MB
COLD ADVECTION WITH 850 MB TEMPERATURES FALLING FROM 10C TO 0-2C
DURING THE AFTERNOON. WOULD EXPECT A NON-DIURNAL TEMPERATURE RANGE
ON TUESDAY WITH HIGHS IN THE 40S TO AROUND 50 LIKELY BEING REACHED
LATE MORNING/EARLY AFTERNOON. PRECIPITATION PROBABILITIES RANGE
FROM LIKELY AHEAD OF THE FRONT ON TUESDAY BEFORE TAPERING QUICKLY
WITH WESTWARD EXTENT. WHILE RAIN IS EXPECTED AHEAD OF THE
FRONT...ANY LIGHT PRECIPITATION THAT OCCURS BEHIND THE FRONT COULD
MIX TO SNOW SHOWERS IN THE NORTHERN ADIRONDACKS AS THERMAL
PROFILES COOL. THE FRONT COULD BE A LITTLE SLOW TO MOVE OUT OF
VERMONT ON TUESDAY NIGHT AS UPPER FLOW BECOMES MORE BOUNDARY-
PARALLEL...SO HAVE CARRIED SLIGHT CHANCE TO CHANCE PRECIPITATION
PROBABILITIES INTO TUESDAY NIGHT.
THE REST OF THE EXTENDED IS RATHER BENIGN AS SFC HIGH PRESSURE
BECOMES ESTABLISHED NORTH OF THE REGION. SEVERAL WEAK MID-LEVEL
SHORTWAVE TROUGHS TRAVERSE THE REGION LATE IN THE WEEK...THOUGH THE
TROUGHS WILL HAVE LIMITED MOISTURE TO WORK WITH. SO WHILE THE
TROUGHS MAY PRODUCE SOME CLOUDS HAVE KEPT THE FORECAST DRY. 850 MB
TEMPERATURES OF -3 TO -6C WEDNESDAY AND THURSDAY RESULT IN HIGHS IN
THE 40S AND LOWS IN THE 20S BOTH DAYS. MODERATING TEMPERATURES ARE
EXPECTED BY LATE WEEK AS 850MB TEMPERATURES RECOVER TO AROUND
0C.
&&
.AVIATION /05Z SUNDAY THROUGH THURSDAY/...
THROUGH 00Z MONDAY...VFR CONDITIONS EXPECTED THROUGH THE PERIOD. A
WARM FRONT WILL PASS ACROSS THE REGION TONIGHT AND SUNDAY MORNING
WITH INCREASING CLOUDS AND SOME VERY LIGHT PRECIPITATION.
HOWEVER...CEILINGS AND VISIBILITIES ARE EXPECTED TO REMAIN VFR AT
ALL TAF SITES. SOME PATCHES OF LIGHT PRECIPITATION ARE POSSIBLE
THIS EVENING...MAINLY IN THE FORM OF LIGHT RAIN OR
DRIZZLE...HOWEVER A BRIEF PERIOD OF VERY LIGHT FREEZING RAIN IS
POSSIBLE AT SLK/MPV BEFORE TEMPERATURES RISE OVERNIGHT. GREATEST
CHANCE OF PRECIPITATION WILL OCCUR AFTER 05Z AND INTO THE FIRST
PART OF SUNDAY MORNING. HOWEVER ASIDE FROM A POSSIBLE VERY BRIEF
PERIOD OF FREEZING RAIN AT SLK/MPV...IT WILL REMAIN LIGHT AND IN
THE FORM OF LIQUID RAIN. ANY REMAINING RAIN SHOWERS WILL COME TO
AN END AFTER 14Z SUNDAY MORNING WITH GENERALLY DRYING AND CLEARING
SKIES BY THE AFTERNOON. SOUTH WINDS WILL BE INCREASING LATER
TONIGHT AND INTO SUNDAY...WITH SOME GUSTS 15-25 KNOTS BY THE
AFTERNOON.
OUTLOOK 00Z MONDAY THROUGH THURSDAY...
00Z MONDAY THROUGH 00Z TUESDAY...VFR UNDER RIDGE OF HIGH PRESSURE.
GUSTY SOUTH WINDS LIKELY...ESPECIALLY MONDAY AFTERNOON. 00Z
TUESDAY THROUGH 00Z WEDNESDAY...PERIODS OF MVFR/IFR IN RAIN
SHOWERS AS A COLD FRONT MOVES ACROSS THE REGION. 00Z WEDNESDAY
ONWARD...VFR UNDER BUILDING HIGH PRESSURE.
&&
.CLIMATE...
RECORD MAXIMUM TEMPERATURES FOR MONDAY NOVEMBER 12TH:
BURLINGTON - 66 IN 1982
MONTPELIER - 62 IN 1982
ST. JOHNSBURY - 65 IN 1911
MASSENA - 70 IN 1982
&&
.BTV WATCHES/WARNINGS/ADVISORIES...
VT...NONE.
NY...NONE.
&&
$$
SYNOPSIS...EVENSON
NEAR TERM...JMG/SLW
SHORT TERM...EVENSON
LONG TERM...LOCONTO
AVIATION...MUCCILLI
CLIMATE...
AREA FORECAST DISCUSSION
NWS RALEIGH NC
815 PM EST MON NOV 12 2012
.SYNOPSIS...
A COLD FRONT WILL MOVE ACROSS THE REGION TONIGHT AND EARLY
TUESDAY...REACHING THE CAROLINA COAST TUESDAY AFTERNOON. COOL HIGH
PRESSURE WILL BUILD RAPIDLY INTO THE AREA BEHIND THE FRONT. AN UPPER
LEVEL DISTURBANCE WILL BRING ANOTHER CHANCE OF RAIN TO MUCH OF THE
REGION BY THURSDAY.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 800 PM MONDAY...
UPDATE...SURFACE COLD FRONT IS DRAPED ALONG THE MOUNTAINS AND IS ON
TRACK TO MOVE ACROSS THE AREA IN THE MIDNIGHT TO MID MORNING TIME
FRAME. SHOWERS HAVE BEEN STUBBORNLY REFUSING TO CROSS THE YADKIN
RIVER THIS EVENING...AND THE LATEST RUC AND WRF MODELS SHOW THAT
THEY SHOULD BE PUSHING INTO THE WESTERN PIEDMONTS BY 03Z. WILL MAKE
SOME MINOR TIMING DELAY TWEAKS TO THE POPS. TEMPS WILL NEED A TWEAK
UPWARD AS WELL...WITH WARM AIR ADVECTION MAINTAINING LOW AND MID 60S
OVER MOST OF THE AREA.
PREVIOUS DISCUSSION...
SURFACE COLD FRONT WAS STARTING TO APPROACH THE MOUNTAINS LATE THIS
AFTERNOON....AND IT WILL GRADUALLY MOVE ACROSS CENTRAL NORTH
CAROLINA OVERNIGHT. THE NAM IS SLIGHTLY FASTER THAN THE GFS WITH THE
FRONTAL PASSAGE...WHICH MAKES A LOT OF DIFFERENCE REGARDING
OVERNIGHT LOWS. BASED ON THE WEAKENING UPPER SUPPORT AS THE FRONT
MOVES EAST...AND GIVEN THE STRENGTH OF HIGH PRESSURE OFFSHORE ON THE
MORNING 12Z UPPER-AIR ANALYSIS...HAVE LEANED MORE TOWARD THE SLOWER
GFS FOR THIS FORECAST.
AS THE UPPER TROUGH LIFTS NORTHEAST AWAY FROM THE FORECAST AREA...
THE RIGHT ENTRANCE REGION OF THE MID- AND UPPER-LEVEL JETS WEAKENS
AS WELL ON BOTH THE NAM AND GFS. BOTH MODELS ALSO SHOW THE BEST LIFT
OVERNIGHT BEING CERTAINLY IN THE NORTHWEST PIEDMONT TOWARD THE
TRIAD...CLOSER TO THE STRONGEST PART OF THE JET AND WHERE THE
DEEPEST MOISTURE IS FORECAST OVERALL IN THE HIGHEST 850MB THETA-E
AIR. THE RESULT SHOULD BE THAT SHOWERS BECOME NUMEROUS TO WIDESPREAD
TOWARD THE TRIAD OVERNIGHT...WITH LIKELY A SLOW PROGRESS EAST OF ANY
ORGANIZED PRECIPITATION OUTSIDE OF THE ISOLATED TO WIDELY SCATTERED
WARM-BASED SHOWERS IN THE MOIST ATLANTIC FLOW...AND VERY WEAK
ISENTROPIC LIFT ON THE 300K SURFACE. ECHO TOPS ON THE SHOWERS HAVE
PERSISTENTLY BEEN BELOW 15K FEET DURING THE EARLY AFTERNOON. BUFR
SOUNDINGS DO NOT REALLY SUPPORT THUNDER...BUT MORE THAN ONE WRF
MODEL REFLECTIVITY GUIDANCE SUGGESTS THE POTENTIAL FOR ELEVATED...
DEEPER CONVECTION TOWARD THE TRIAD...WHERE THE GFS BUFR SOUNDINGS
FOR THAT AREA SHOW MODEST LAYER WARMING FROM 850MB TO 700MB THIS
EVENING. IF THUNDER WOULD OCCUR...WOULD THINK IT WOULD BE A RUMBLE
OR THREE. SPC DID PUSH ITS GENERAL THUNDER POTENTIAL NORTHEAST
THROUGH THE WESTERN PIEDMONT AND BASED ON THE COUPLE OF WRF MODELS
CAN SEE WHY THIS WAS DONE. IT IS A MARGINAL POTENTIAL...BUT LIFTED
INDICES TOWARD THE YADKIN RIVER DO FALL CLOSE TO 0C ON THE GFS
TONIGHT AHEAD OF THE FRONT.
PRECIPITATION AMOUNT POTENTIAL ALMOST CERTAINLY SEEMS GREATER TOWARD
THE TRIAD...WHERE A HALF-INCH ON AVERAGE COULD OCCUR BY 12Z TUESDAY.
FARTHER EAST...TOWARD U.S. 1...POTENTIAL RAINFALL AMOUNTS COULD FALL
QUICKLY TO JUST AROUND A TENTH BY SUNRISE. ALTHOUGH PREFERRED THE
GFS IN TERMS OF FRONTAL TIMING...THE AMOUNT OF COLD AIR BEHIND THE
FRONT IS ENOUGH THAT FOR THIS FORECAST OPTED TO BLEND LOWS BETWEEN
THE MAV AND MET MOS GUIDANCE. EXPECT LOWS IN THE MID 40S IN THE
IMMEDIATE TRIAD...TO NEAR OR JUST AFTER SUNRISE VALUES IN THE MID
50S TOWARD KFAY AND KCTZ...AROUND 50 IN BETWEEN.
&&
.SHORT TERM /TUESDAY THROUGH THURSDAY NIGHT/...
AS OF 235 PM MONDAY...
THE SURFACE FRONT SHOULD BE LOCATED JUST EAST OF CENTRAL NORTH
CAROLINA AROUND 12Z TUESDAY...HEADED TOWARD THE COAST. THE 850MB
FRONT IS SLOWER TO PUSH EAST ATOP THE SHALLOW COLD AIR...WITH THE
GFS ONLY FORECASTING THE 850MB FRONT NEAR THE TRIAD BY 12Z
TUESDAY...AND APPROACHING THE COASTAL PLAIN BY 00Z WEDNESDAY. ON
AVERAGE ACROSS CENTRAL NORTH CAROLINA...AS THE WEAKENING JET MOVES
EAST AND LIFT AND THETA-E RIDGING WEAKEN AS WELL...THE INTENSITY AND
COVERAGE OF PRECIPITATION SHOULD WANE SOME WITH EASTWARD MOVEMENT.
IT IS POSSIBLE THAT THROUGHOUT THIS EVENT AVERAGE PRECIPITATION
AMOUNTS OVER THE COASTAL PLAIN ONLY END UP BETWEEN A TENTH AND
TWO-TENTHS INCH.
BUFR SOUNDINGS TOWARD THE TRIAD DRY FAST BY 18Z...WITH CONSIDERABLE
ESPECIALLY LOW-LEVEL MOISTURE BEING SLOW TO ERODE ESPECIALLY FROM
ABOUT U.S. 1 EAST. DEPENDING ON FRONTAL TIMING AND LESS CERTAINTY OF
PRECIPITATION COVERAGE WITH EASTERN EXTENT...OPTED FOR BROAD LIKELY
CHANCES FOR RAIN EARLY TUESDAY WITH A SLOW DIMINISHING OF CHANCES
WEST TO EAST...ENDING IN THE TRIAD BY 18Z. AS THE MID-LEVELS DRY OUT
TUESDAY AFTERNOON...AND THE 850MB FRONT IS FORECAST TO BECOME
DIFFUSE LATE IN THE DAY...THERE MAY BE ONLY ENOUGH LIFT AND MOISTURE
TO RESULT IN ISOLATED SHOWERS OR AREAS OF SPRINKLES/DRIZZLE EAST OF
U.S. 1 EARLY TUESDAY EVENING. OVERNIGHT TUESDAY...BUFR SOUNDINGS
FROM BOTH THE NAM AND GFS SEEM TOO DRY OVERALL TO SUPPORT THE
MENTION OF PRECIPITATION AS SUBSIDENCE INCREASES THROUGH 500MB...
WITH A MID-LEVEL SHORTWAVE RIDGE FORECAST OVER CENTRAL NORTH
CAROLINA BY 12Z WEDNESDAY. TEMPERATURES SHOULD REMAIN NEARLY STEADY
AFTER SUNRISE...OR SLOWLY FALL AND THEN BECOME STEADY...WITH SOME
POTENTIAL FOR MINOR RECOVERY TOWARD THE TRIAD SHOULD CLOUDS ERODE AS
FORECAST WITH DRYING DURING THE AFTERNOON. AGAIN...LEANED TOWARD A
BLEND OF GUIDANCE FOR HIGHS TUESDAY...AND TO THE COOLER MOS FOR
TUESDAY NIGHT. -DJF
WEDNESDAY THROUGH THURSDAY NIGHT...SHORTWAVE RIDGING WILL BRIEFLY
BUILD OVER THE REGION DURING THE DAY ON WEDNESDAY...WHILE AT THE
SURFACE HIGH PRESSURE WILL RIDGE DOWN INTO THE AREA FROM THE NORTH
AS A MID LEVEL TROUGH AND ASSOCIATED COLD FRONT MOVE EAST OF THE
AREA. THIS WILL RESULT IN A DRY DAY...WITH MOSTLY SUNNY TO PARTLY
CLOUDY SKIES...ALTHOUGH CLOUDS WILL BE ON THE INCREASE DURING THE
AFTERNOON HOURS. FORECAST CONFIDENCE FOR THE WEDNESDAY NIGHT INTO
THURSDAY TIME FRAME CONTINUES TO BE BELOW AVERAGE AS MODELS STILL
ARE HAVING TROUBLE RESOLVING THE EVOLUTION OF A SHORT WAVE THAT IS
CURRENTLY COMING ASHORE ALONG THE PACIFIC COAST. THE ECMWF HAS BEEN
FAIRLY CONSISTENT FOR THE PAST SEVERAL RUNS WITH SHOWING THIS SHORT
WAVE AMPLIFYING INTO THE DEEP SOUTH AND SPREADING SOME FAIRLY
SIGNIFICANT PRECIP INTO CENTRAL NC LATE WEDNESDAY INTO THURSDAY...
POSSIBLY EVEN LINGERING INTO THURSDAY NIGHT. HOWEVER...THE GFS AND
NAM HAVE SHOWN A MORE PROGRESSIVE AND FLATTER WAVE AS IT COMES
ACROSS THE REGION AND LITTLE TO NO PRECIP AS IT PASSES. HOWEVER...
THE 12Z GFS HAS TRENDED A LITTLE DEEPER WITH THIS WAVE AND NOW SHOWS
SOME MEASURABLE PRECIP ACROSS THE AREA...ALTHOUGH STILL NOT AS MUCH
AS THE ECMWF. WILL USE A BLEND OF THE LATEST GFS AND ECMWF FOR THE
CURRENT FORECAST PACKAGE. THIS RESULTS IN RAIN CHANCES INCREASING
LATE WEDNESDAY NIGHT INTO THURSDAY...BEFORE TAPERING OFF THURSDAY
EVENING. A CHILLY POST FRONTAL AIR MASS WILL RESULT IN BELOW NORMAL
TEMPS FOR WEDNESDAY...WITH VERY LITTLE RECOVERY EXPECTED FOR
THURSDAY DUE TO THE INCREASE IN CLOUDS AND PRECIP CHANCES. -KRR
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 250 PM MONDAY...
RATHER HIGH UNCERTAINTY CONTINUES FOR THE LONG TERM PERIOD AS MODELS
CONTINUE TO PROG A CUT OFF UPPER LOW DEVELOPING SOMEWHERE ACROSS THE
SOUTHEAST US BY THE WEEKEND AND INTO EARLY NEXT WEEK. THE ECMWF
CONTINUES TO BE STRONGER WITH THIS LOW AND TRACKS IT FURTHER
SOUTH...EVENTUALLY MOVING OFFSHORE OF THE SOUTHEAST COAST LATE IN
THE WEEKEND OR EARLY NEXT WEEK. THIS SOLUTION WOULD RESULT IN A
PROLONGED PERIOD OF PRECIP FOR ALL OF CENTRAL NC...POSSIBLY
BEGINNING LATE SATURDAY AND PERSISTING THROUGH EARLY NEXT WEEK. THE
GFS ALSO SHOWS A LOW CUTTING OFF DURING THIS TIME FRAME...BUT IS
SLIGHTLY WEAKER AND DOES NOT TRACK IT AS FAR SOUTH...BUT INSTEAD
SHOWS A MORE EASTERN PROGRESSION OF THIS LOW. THIS SOLUTION WOULD
RESULT IN LESS OVERALL PRECIP FOR THE REGION. DUE TO THE HIGH
UNCERTAINTY WILL FOLLOW CLOSELY TO THE ONGOING FORECAST...WHICH
SHOWS INCREASING PRECIP CHANCES BEGINNING ON SATURDAY (BUT NO HIGHER
THAN SLIGHT CHANCE FOR NOW) AND CONTINUED CLOUDY AND BELOW NORMAL
TEMPS THROUGH THE ENTIRE PERIOD.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
AS OF 708 PM MONDAY...
VFR CONDITIONS THIS EVENING ARE EXPECTED TO DETERIORATE OVERNIGHT
WITH THE WEST TO EAST PASSAGE OF A COLD FRONT. THE FRONT IS EXPECTED
TO MAKE IT TO KINT AND KGSO AOA 06Z...KRDU AOA 09Z...AND KFAY AND
KRWI AOA 12Z. AS THE FRONT APPROACHES...EXPECT WIDESPREAD MVFR
CEILINGS ARE WITH SPOTTY/SCATTERED SHOWERS ALONG THE FRONT. IT IS
IMPOSSIBLE THAT AREAS IN THE EAST THAT WILL REMAIN IN THE WARM HUMID
SECTOR AHEAD OF THE FRONT((KFAY AND KRWI)COULD SEE A PERIOD OF IFR
CEILINGS AND FOG.
HOWEVER CONFIDENCE IN THESE IFR CEILINGS DEVELOPING ARE LOW AND WILL
BE FORECAST AS A TEMPO GROUP FOR NOW.
VFR CONDITIONS COULD RETURN AS EARLY AS 15Z IN THE WEST...BUT COULD
PERSIST AS LATE AS 00Z TUE IN THE EAST UNTIL THE ARRIVAL OF DRIER
AIR ALOFT WITH THE PASSAGE OF THE H8 COLD FRONT. A BRIEF PERIOD OF
LIGHT RAIN AND MVFR CONDITIONS ARE POSSIBLE LATE WEDNESDAY NIGHT AND
EARLY THURSDAY AHEAD OF AN UPPER LEVEL DISTURBANCE AND WEAK SURFACE
LOW PRESSURE. MVFR CONDITIONS ARE ALSO POSSIBLE SATURDAY DEPENDING
ON THE LOCATION OF LOW PRESSURE OFF OF THE CAROLINA COAST.
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...DJF
NEAR TERM...MLM/DJF
SHORT TERM...DJF/KRR
LONG TERM...KRR
AVIATION...CBL
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1022 PM EST MON NOV 12 2012
.SYNOPSIS...
HIGH PRESSURE WILL BEGIN BUILDING INTO THE AREA FROM THE
SOUTHWEST TONIGHT AND THEN MOVE OVER THE AREA TUESDAY AND
WEDNESDAY. THE HIGH PRESSURE CENTER WILL MOVE NORTHEAST OF THE
AREA...BUT WILL CONTINUE TO RIDGE OVER THE AREA THROUGH THE
SECOND HALF OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
UPDATE...WILL UPDATE ONE MORE TIME FOR CLOUD AND PRECIP TRENDS.
PREVIOUS...THE COLD FRONT THAT MOVED THROUGH THE AREA TODAY IS
MOVING OUT OF THE FORECAST AREA AS OF 20Z. RAIN WILL CONTINUE
ESPECIALLY ACROSS THE EASTERN HALF OF THE AREA THROUGH THE
REMAINDER OF THE AFTERNOON AND EVENING. MEANWHILE...THERE IS A
SHARP CUTOFF TO BOTH PRECIP AND CLOUDS ACROSS THE WEST WITH
SATELLITE SHOWING CLEARING MOVING INTO NW OH ALREADY THIS
AFTERNOON. OBS HAVE SHOWN A MIX OF RAIN AND SNOW ACROSS WESTERN
COUNTIES BUT RAIN ELSEWHERE. MADE ONLY SMALL ADJUSTMENTS TO POPS
THROUGH EARLY TONIGHT WITH THE RAIN CONTINUING TO PUSH EASTWARD
AND DECREASING POPS FROM WEST TO EAST. WITH THAT MENTION ONLY CHC
POPS ACROSS THE WEST FOR EARLY TONIGHT...THEN DRY AFTER MIDNIGHT.
ONCE THIS AREA OF SHOWERS DEPARTS TO THE EAST THE FOCUS WILL BE ON
LAKE EFFECT SNOW SHOWERS. WITH H850 TEMPS DROPPING DOWN TO -8C OR
SO AND INVERSIONS SHOWN ON BUFKIT SOUNDING STILL A BIT HIGH
EXPECTING LINGERING CLOUDS WITH WEST WINDS ACROSS NE OH AND NW PA
AFTER MIDNIGHT TONIGHT. THINKING THAT WITH THE AMOUNT OF DRIER AIR
BUILDING IN THIS WILL LIMIT LAKE EFFECT SNOW DEVELOPMENT AND WILL
HAVE TO WAIT FOR SOME ADDITIONAL SUPPORT LATE OVERNIGHT.
WATER VAPOR AND MODELS SHOWING SHARPER UPPER TROUGH THAT IS
EXPECTED TO SWING ACROSS THE SOUTHERN GREAT LAKES LATE OVERNIGHT
AND TUESDAY MORNING. EXPECTING THIS TO HELP IN GETTING SOME LAKE
EFFECT SNOW ACROSS NE OH AND NW PA. ELSEWHERE EXPECTING PARTLY
CLOUDY SKIES. USED A BLEND OF MET AND MAV TEMPS WITH HRRR TRENDS
IN THE VERY SHORT TERM ON HOURLY TEMPS.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY NIGHT/...
GUIDANCE POPS NOT INDICATING MUCH WITH LAKE EFFECT SNOW
SHOWERS...BUT WENT WITH AT LEAST HIGH CHC POPS ACROSS NE OH AND NW
PA TUESDAY MORNING. WITH THE WEST FLOW NOT EXPECTING MUCH ACROSS
GREATER CLEVELAND AREA...WITH BEST ACCUMS STRETCHING FROM CENTRAL
ASHTABULA COUNTY INTO INTERIOR ERIE COUNTY. THINKING FURTHER SOUTH
THROUGH CRAWFORD COUNTIES AMOUNTS WILL DIMINISH. BETTER SFC
CONVERGENCE OFF THE LAKE APPEARS TO BE IN THIS AREA ALSO. OVERALL
THOUGH THINKING ACCUMS WILL RANGE AROUND AN INCH OR SO ACROSS
INTERIOR NW PA TO LESS THAN AN INCH BACK INTO FAR NE OH COUNTIES.
BY AFTERNOON THE TROUGH PUSHES TO THE EAST AND DRIER AIR OVERCOMES
THE LAKE EFFECT POTENTIAL. SOME LINGERING CLOUDS AND PERHAPS SOME
FLURRIES POSSIBLE ACROSS HIGHER ELEVATIONS OF NW PA...BUT NOT
EXPECTING ANY FURTHER ACCUMS. FOR THE REMAINDER OF THE AREA HIGH
PRESSURE INFLUENCE WILL HELP ALLOW FOR SUNSHINE. TEMPS EXPECTED TO
RANGE IN MID TO UPPER 30S ACROSS THE NORTHEAST WITH CLOUDS AND AM
SNOW SHOWERS...TO LOWER 40S ACROSS THE SOUTH AND WEST.
FROM TUESDAY NIGHT THROUGH THURSDAY NIGHT HIGH PRESSURE IS
EXPECTED TO BE IN CONTROL ACROSS THE AREA WITH DRY CONDITIONS.
SOME ISSUES WITH CLOUD COVER THROUGH THE PERIOD AS MODELS
CONTINUING TO SHOW SOME WEAK UPPER TROUGHS MOVING THROUGH THE
UPPER FLOW DURING THE PERIOD. DESPITE THAT MAINLY QUIET WEATHER
WITH TEMPS TRENDING TOWARD NORMAL ARE EXPECTED. LEANED TOWARD A
BLEND OF MET MAV AND MEX NUMBER THROUGH THE PERIOD AS SEEING NO
REASON TO DEVIATE MUCH WITH HIGH PRESSURE INFLUENCE.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
HIGH PRESSURE WILL BE THE DOMINANT FEATURE THROUGH THE EXTENDED EVEN
AS THE CENTER OF IT DRIFTS INTO EASTERN QUEBEC PROVINCE. SO AT THIS
POINT WE EXPECT TO SEE DRY CONDITIONS. THERE MAY BE A SLIGHT
INCREASE IN CLOUD COVER ON SUNDAY AS A STORM SYSTEM TAKES SHAPE OFF
THE MIDDLE ATLANTIC COAST. OTHERWISE EXPECT TO SEE TEMPERATURES NEAR
TO SLIGHTLY BELOW AVERAGE THROUGH THE PERIOD.
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
COLD FRONT IS EAST OF KERI. PRECIP SHIELD EXTENDS BACK TO KCGF AND
KBJJ AS OF 23Z AND WILL CONTINUE TO SHIFT EAST THIS EVENING. RIGHT
BEFORE THE PRECIP ENDS THERE MAY BE SOME SN/RA MIX...BUT NOT
SIGNIFICANT ENOUGH TO INCLUDE. AS THE PRECIP ENDS THE VSBY AND
CIGS IMPROVE TO VFR OR HIGH END MVFR AND WINDS SHIFT FROM THE WEST
TO THE SOUTHWEST. THERE WILL EVEN BE A PERIOD OF CLEARING FOR
KFDY. THE REST OF THE AREA WILL SIT AT VFR/MVFR FOR SEVERAL HOURS
TONIGHT. A SECONDARY TROUGH WILL SWING ACROSS THE EASTERN GREAT
LAKES FOR THE SECOND HALF OF THE NIGHT/TUESDAY MORNING BRINGING
MVFR CIGS. THE BEST MOISTURE STAYS TO OUR NORTH...BUT IT WILL BE
COLD ENOUGH FOR SOME LAKE EFFECT WITH THE TROUGH. WILL MENTION A
SNRA MIX FOR ERIE IN A TEMPO...BUT THAT IS IT. FORECAST SOUNDING
PROFILES ARE NOT SUGGESTING MUCH WITH THE LACK OF DEEPER
MOISTURE. WINDS SHIFT TO THE NORTHWEST TUESDAY AFTERNOON. HIGH
PRESSURE FOLLOWS FOR TUESDAY NIGHT.
OUTLOOK...SOME NON-VFR POSSIBLE FRIDAY.
&&
.MARINE...
THE COLD FRONT IS JUST EAST OF THE FORECAST AREA. WINDS DIE DOWN
BEHIND THE FRONT BUT AS THE MUCH COLDER AIR MOVES OVER THE LAKE
INCREASED MIXING WILL OCCUR OVER THE LAKE. THE 850MB TEMPS FORECAST
TO DIP TO MINUS 10C BY DAYBREAK TUESDAY. AS A RESULT THE SMALL
CRAFT WILL BE NEEDED OVER THE LAKE THROUGH THE OVERNIGHT HOURS.
THE WINDS WILL DIE DOWN SIGNIFICANTLY BY TOMORROW AFTERNOON AS
HIGH PRESSURE BUILDS OVER THE LAKE. EXPECT CONDITIONS TO REMAIN
BELOW SMALL CRAFT ADVISORY CRITERIA THROUGH THE WEEKEND AS HIGH
PRESSURE WILL REMAIN OVER THE LAKE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 AM EST TUESDAY FOR LEZ145>149.
SMALL CRAFT ADVISORY UNTIL 4 AM EST TUESDAY FOR LEZ142>144.
&&
$$
SYNOPSIS...ABE
NEAR TERM...ABE/TK
SHORT TERM...ABE
LONG TERM...MULLEN
AVIATION...OUDEMAN
MARINE...DJB/OUDEMAN
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
954 PM EST MON NOV 12 2012
.SYNOPSIS...
HIGH PRESSURE WILL BEGIN BUILDING INTO THE AREA FROM THE
SOUTHWEST TONIGHT AND THEN MOVE OVER THE AREA TUESDAY AND
WEDNESDAY. THE HIGH PRESSURE CENTER WILL MOVE NORTHEAST OF THE
AREA...BUT WILL CONTINUE TO RIDGE OVER THE AREA THROUGH THE
SECOND HALF OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
UPDATE...UPDATED FOR CLOUD AND PRECIP TRENDS. ALSO ADJUSTED TEMPS
OVERNIGHT AND INTO THE MORNING.
PREVIOUS...THE COLD FRONT THAT MOVED THROUGH THE AREA TODAY IS
MOVING OUT OF THE FORECAST AREA AS OF 20Z. RAIN WILL CONTINUE
ESPECIALLY ACROSS THE EASTERN HALF OF THE AREA THROUGH THE
REMAINDER OF THE AFTERNOON AND EVENING. MEANWHILE...THERE IS A
SHARP CUTOFF TO BOTH PRECIP AND CLOUDS ACROSS THE WEST WITH
SATELLITE SHOWING CLEARING MOVING INTO NW OH ALREADY THIS
AFTERNOON. OBS HAVE SHOWN A MIX OF RAIN AND SNOW ACROSS WESTERN
COUNTIES BUT RAIN ELSEWHERE. MADE ONLY SMALL ADJUSTMENTS TO POPS
THROUGH EARLY TONIGHT WITH THE RAIN CONTINUING TO PUSH EASTWARD
AND DECREASING POPS FROM WEST TO EAST. WITH THAT MENTION ONLY CHC
POPS ACROSS THE WEST FOR EARLY TONIGHT...THEN DRY AFTER MIDNIGHT.
ONCE THIS AREA OF SHOWERS DEPARTS TO THE EAST THE FOCUS WILL BE ON
LAKE EFFECT SNOW SHOWERS. WITH H850 TEMPS DROPPING DOWN TO -8C OR
SO AND INVERSIONS SHOWN ON BUFKIT SOUNDING STILL A BIT HIGH
EXPECTING LINGERING CLOUDS WITH WEST WINDS ACROSS NE OH AND NW PA
AFTER MIDNIGHT TONIGHT. THINKING THAT WITH THE AMOUNT OF DRIER AIR
BUILDING IN THIS WILL LIMIT LAKE EFFECT SNOW DEVELOPMENT AND WILL
HAVE TO WAIT FOR SOME ADDITIONAL SUPPORT LATE OVERNIGHT.
WATER VAPOR AND MODELS SHOWING SHARPER UPPER TROUGH THAT IS
EXPECTED TO SWING ACROSS THE SOUTHERN GREAT LAKES LATE OVERNIGHT
AND TUESDAY MORNING. EXPECTING THIS TO HELP IN GETTING SOME LAKE
EFFECT SNOW ACROSS NE OH AND NW PA. ELSEWHERE EXPECTING PARTLY
CLOUDY SKIES. USED A BLEND OF MET AND MAV TEMPS WITH HRRR TRENDS
IN THE VERY SHORT TERM ON HOURLY TEMPS.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY NIGHT/...
GUIDANCE POPS NOT INDICATING MUCH WITH LAKE EFFECT SNOW
SHOWERS...BUT WENT WITH AT LEAST HIGH CHC POPS ACROSS NE OH AND NW
PA TUESDAY MORNING. WITH THE WEST FLOW NOT EXPECTING MUCH ACROSS
GREATER CLEVELAND AREA...WITH BEST ACCUMS STRETCHING FROM CENTRAL
ASHTABULA COUNTY INTO INTERIOR ERIE COUNTY. THINKING FURTHER SOUTH
THROUGH CRAWFORD COUNTIES AMOUNTS WILL DIMINISH. BETTER SFC
CONVERGENCE OFF THE LAKE APPEARS TO BE IN THIS AREA ALSO. OVERALL
THOUGH THINKING ACCUMS WILL RANGE AROUND AN INCH OR SO ACROSS
INTERIOR NW PA TO LESS THAN AN INCH BACK INTO FAR NE OH COUNTIES.
BY AFTERNOON THE TROUGH PUSHES TO THE EAST AND DRIER AIR OVERCOMES
THE LAKE EFFECT POTENTIAL. SOME LINGERING CLOUDS AND PERHAPS SOME
FLURRIES POSSIBLE ACROSS HIGHER ELEVATIONS OF NW PA...BUT NOT
EXPECTING ANY FURTHER ACCUMS. FOR THE REMAINDER OF THE AREA HIGH
PRESSURE INFLUENCE WILL HELP ALLOW FOR SUNSHINE. TEMPS EXPECTED TO
RANGE IN MID TO UPPER 30S ACROSS THE NORTHEAST WITH CLOUDS AND AM
SNOW SHOWERS...TO LOWER 40S ACROSS THE SOUTH AND WEST.
FROM TUESDAY NIGHT THROUGH THURSDAY NIGHT HIGH PRESSURE IS
EXPECTED TO BE IN CONTROL ACROSS THE AREA WITH DRY CONDITIONS.
SOME ISSUES WITH CLOUD COVER THROUGH THE PERIOD AS MODELS
CONTINUING TO SHOW SOME WEAK UPPER TROUGHS MOVING THROUGH THE
UPPER FLOW DURING THE PERIOD. DESPITE THAT MAINLY QUIET WEATHER
WITH TEMPS TRENDING TOWARD NORMAL ARE EXPECTED. LEANED TOWARD A
BLEND OF MET MAV AND MEX NUMBER THROUGH THE PERIOD AS SEEING NO
REASON TO DEVIATE MUCH WITH HIGH PRESSURE INFLUENCE.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
HIGH PRESSURE WILL BE THE DOMINANT FEATURE THROUGH THE EXTENDED EVEN
AS THE CENTER OF IT DRIFTS INTO EASTERN QUEBEC PROVINCE. SO AT THIS
POINT WE EXPECT TO SEE DRY CONDITIONS. THERE MAY BE A SLIGHT
INCREASE IN CLOUD COVER ON SUNDAY AS A STORM SYSTEM TAKES SHAPE OFF
THE MIDDLE ATLANTIC COAST. OTHERWISE EXPECT TO SEE TEMPERATURES NEAR
TO SLIGHTLY BELOW AVERAGE THROUGH THE PERIOD.
&&
.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
COLD FRONT IS EAST OF KERI. PRECIP SHIELD EXTENDS BACK TO KCGF AND
KBJJ AS OF 23Z AND WILL CONTINUE TO SHIFT EAST THIS EVENING. RIGHT
BEFORE THE PRECIP ENDS THERE MAY BE SOME SN/RA MIX...BUT NOT
SIGNIFICANT ENOUGH TO INCLUDE. AS THE PRECIP ENDS THE VSBY AND
CIGS IMPROVE TO VFR OR HIGH END MVFR AND WINDS SHIFT FROM THE WEST
TO THE SOUTHWEST. THERE WILL EVEN BE A PERIOD OF CLEARING FOR
KFDY. THE REST OF THE AREA WILL SIT AT VFR/MVFR FOR SEVERAL HOURS
TONIGHT. A SECONDARY TROUGH WILL SWING ACROSS THE EASTERN GREAT
LAKES FOR THE SECOND HALF OF THE NIGHT/TUESDAY MORNING BRINGING
MVFR CIGS. THE BEST MOISTURE STAYS TO OUR NORTH...BUT IT WILL BE
COLD ENOUGH FOR SOME LAKE EFFECT WITH THE TROUGH. WILL MENTION A
SNRA MIX FOR ERIE IN A TEMPO...BUT THAT IS IT. FORECAST SOUNDING
PROFILES ARE NOT SUGGESTING MUCH WITH THE LACK OF DEEPER
MOISTURE. WINDS SHIFT TO THE NORTHWEST TUESDAY AFTERNOON. HIGH
PRESSURE FOLLOWS FOR TUESDAY NIGHT.
OUTLOOK...SOME NON-VFR POSSIBLE FRIDAY.
&&
.MARINE...
THE COLD FRONT IS JUST EAST OF THE FORECAST AREA. WINDS DIE DOWN
BEHIND THE FRONT BUT AS THE MUCH COLDER AIR MOVES OVER THE LAKE
INCREASED MIXING WILL OCCUR OVER THE LAKE. THE 850MB TEMPS FORECAST
TO DIP TO MINUS 10C BY DAYBREAK TUESDAY. AS A RESULT THE SMALL
CRAFT WILL BE NEEDED OVER THE LAKE THROUGH THE OVERNIGHT HOURS.
THE WINDS WILL DIE DOWN SIGNIFICANTLY BY TOMORROW AFTERNOON AS
HIGH PRESSURE BUILDS OVER THE LAKE. EXPECT CONDITIONS TO REMAIN
BELOW SMALL CRAFT ADVISORY CRITERIA THROUGH THE WEEKEND AS HIGH
PRESSURE WILL REMAIN OVER THE LAKE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 AM EST TUESDAY FOR LEZ145>149.
SMALL CRAFT ADVISORY UNTIL 4 AM EST TUESDAY FOR LEZ142>144.
&&
$$
SYNOPSIS...ABE
NEAR TERM...ABE/TK
SHORT TERM...ABE
LONG TERM...MULLEN
AVIATION...OUDEMAN
MARINE...DJB/OUDEMAN
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
840 PM EST MON NOV 12 2012
.SYNOPSIS...
HIGH PRESSURE WILL BEGIN BUILDING INTO THE AREA FROM THE
SOUTHWEST TONIGHT AND THEN MOVE OVER THE AREA TUESDAY AND
WEDNESDAY. THE HIGH PRESSURE CENTER WILL MOVE NORTHEAST OF THE
AREA...BUT WILL CONTINUE TO RIDGE OVER THE AREA THROUGH THE
SECOND HALF OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
UPDATE...UPDATED FOR CLOUD AND PRECIP TRENDS. ALSO ADJUSTED TEMPS
OVERNIGHT AND INTO THE MORNING.
PREVIOUS...THE COLD FRONT THAT MOVED THROUGH THE AREA TODAY IS
MOVING OUT OF THE FORECAST AREA AS OF 20Z. RAIN WILL CONTINUE
ESPECIALLY ACROSS THE EASTERN HALF OF THE AREA THROUGH THE
REMAINDER OF THE AFTERNOON AND EVENING. MEANWHILE...THERE IS A
SHARP CUTOFF TO BOTH PRECIP AND CLOUDS ACROSS THE WEST WITH
SATELLITE SHOWING CLEARING MOVING INTO NW OH ALREADY THIS
AFTERNOON. OBS HAVE SHOWN A MIX OF RAIN AND SNOW ACROSS WESTERN
COUNTIES BUT RAIN ELSEWHERE. MADE ONLY SMALL ADJUSTMENTS TO POPS
THROUGH EARLY TONIGHT WITH THE RAIN CONTINUING TO PUSH EASTWARD
AND DECREASING POPS FROM WEST TO EAST. WITH THAT MENTION ONLY CHC
POPS ACROSS THE WEST FOR EARLY TONIGHT...THEN DRY AFTER MIDNIGHT.
ONCE THIS AREA OF SHOWERS DEPARTS TO THE EAST THE FOCUS WILL BE ON
LAKE EFFECT SNOW SHOWERS. WITH H850 TEMPS DROPPING DOWN TO -8C OR
SO AND INVERSIONS SHOWN ON BUFKIT SOUNDING STILL A BIT HIGH
EXPECTING LINGERING CLOUDS WITH WEST WINDS ACROSS NE OH AND NW PA
AFTER MIDNIGHT TONIGHT. THINKING THAT WITH THE AMOUNT OF DRIER AIR
BUILDING IN THIS WILL LIMIT LAKE EFFECT SNOW DEVELOPMENT AND WILL
HAVE TO WAIT FOR SOME ADDITIONAL SUPPORT LATE OVERNIGHT.
WATER VAPOR AND MODELS SHOWING SHARPER UPPER TROUGH THAT IS
EXPECTED TO SWING ACROSS THE SOUTHERN GREAT LAKES LATE OVERNIGHT
AND TUESDAY MORNING. EXPECTING THIS TO HELP IN GETTING SOME LAKE
EFFECT SNOW ACROSS NE OH AND NW PA. ELSEWHERE EXPECTING PARTLY
CLOUDY SKIES. USED A BLEND OF MET AND MAV TEMPS WITH HRRR TRENDS
IN THE VERY SHORT TERM ON HOURLY TEMPS.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY NIGHT/...
GUIDANCE POPS NOT INDICATING MUCH WITH LAKE EFFECT SNOW
SHOWERS...BUT WENT WITH AT LEAST HIGH CHC POPS ACROSS NE OH AND NW
PA TUESDAY MORNING. WITH THE WEST FLOW NOT EXPECTING MUCH ACROSS
GREATER CLEVELAND AREA...WITH BEST ACCUMS STRETCHING FROM CENTRAL
ASHTABULA COUNTY INTO INTERIOR ERIE COUNTY. THINKING FURTHER SOUTH
THROUGH CRAWFORD COUNTIES AMOUNTS WILL DIMINISH. BETTER SFC
CONVERGENCE OFF THE LAKE APPEARS TO BE IN THIS AREA ALSO. OVERALL
THOUGH THINKING ACCUMS WILL RANGE AROUND AN INCH OR SO ACROSS
INTERIOR NW PA TO LESS THAN AN INCH BACK INTO FAR NE OH COUNTIES.
BY AFTERNOON THE TROUGH PUSHES TO THE EAST AND DRIER AIR OVERCOMES
THE LAKE EFFECT POTENTIAL. SOME LINGERING CLOUDS AND PERHAPS SOME
FLURRIES POSSIBLE ACROSS HIGHER ELEVATIONS OF NW PA...BUT NOT
EXPECTING ANY FURTHER ACCUMS. FOR THE REMAINDER OF THE AREA HIGH
PRESSURE INFLUENCE WILL HELP ALLOW FOR SUNSHINE. TEMPS EXPECTED TO
RANGE IN MID TO UPPER 30S ACROSS THE NORTHEAST WITH CLOUDS AND AM
SNOW SHOWERS...TO LOWER 40S ACROSS THE SOUTH AND WEST.
FROM TUESDAY NIGHT THROUGH THURSDAY NIGHT HIGH PRESSURE IS
EXPECTED TO BE IN CONTROL ACROSS THE AREA WITH DRY CONDITIONS.
SOME ISSUES WITH CLOUD COVER THROUGH THE PERIOD AS MODELS
CONTINUING TO SHOW SOME WEAK UPPER TROUGHS MOVING THROUGH THE
UPPER FLOW DURING THE PERIOD. DESPITE THAT MAINLY QUIET WEATHER
WITH TEMPS TRENDING TOWARD NORMAL ARE EXPECTED. LEANED TOWARD A
BLEND OF MET MAV AND MEX NUMBER THROUGH THE PERIOD AS SEEING NO
REASON TO DEVIATE MUCH WITH HIGH PRESSURE INFLUENCE.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
HIGH PRESSURE WILL BE THE DOMINANT FEATURE THROUGH THE EXTENDED EVEN
AS THE CENTER OF IT DRIFTS INTO EASTERN QUEBEC PROVINCE. SO AT THIS
POINT WE EXPECT TO SEE DRY CONDITIONS. THERE MAY BE A SLIGHT
INCREASE IN CLOUD COVER ON SUNDAY AS A STORM SYSTEM TAKES SHAPE OFF
THE MIDDLE ATLANTIC COAST. OTHERWISE EXPECT TO SEE TEMPERATURES NEAR
TO SLIGHTLY BELOW AVERAGE THROUGH THE PERIOD.
&&
.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
COLD FRONT IS EAST OF KERI. PRECIP SHIELD EXTENDS BACK TO KCGF AND
KBJJ AS OF 23Z AND WILL CONTINUE TO SHIFT EAST THIS EVENING. RIGHT
BEFORE THE PRECIP ENDS THERE MAY BE SOME SN/RA MIX...BUT NOT
SIGNIFICANT ENOUGH TO INCLUDE. AS THE PRECIP ENDS THE VSBY AND
CIGS IMPROVE TO VFR OR HIGH END MVFR AND WINDS SHIFT FROM THE WEST
TO THE SOUTHWEST. THERE WILL EVEN BE A PERIOD OF CLEARING FOR
KFDY. THE REST OF THE AREA WILL SIT AT VFR/MVFR FOR SEVERAL HOURS
TONIGHT. A SECONDARY TROUGH WILL SWING ACROSS THE EASTERN GREAT
LAKES FOR THE SECOND HALF OF THE NIGHT/TUESDAY MORNING BRINGING
MVFR CIGS. THE BEST MOISTURE STAYS TO OUR NORTH...BUT IT WILL BE
COLD ENOUGH FOR SOME LAKE EFFECT WITH THE TROUGH. WILL MENTION A
SNRA MIX FOR ERIE IN A TEMPO...BUT THAT IS IT. FORECAST SOUNDING
PROFILES ARE NOT SUGGESTING MUCH WITH THE LACK OF DEEPER
MOISTURE. WINDS SHIFT TO THE NORTHWEST TUESDAY AFTERNOON. HIGH
PRESSURE FOLLLOWS FOR TUESDAY NIGHT.
OUTLOOK...SOME NON-VFR POSSIBLE FRIDAY.
&&
.MARINE...
THE COLD FRONT IS JUST EAST OF THE FORECAST AREA. WINDS DIE DOWN
BEHIND THE FRONT BUT AS THE MUCH COLDER AIR MOVES OVER THE LAKE
INCREASED MIXING WILL OCCUR OVER THE LAKE. THE 850MB TEMPS FORECAST
TO DIP TO MINUS 10C BY DAYBREAK TUESDAY. AS A RESULT THE SMALL
CRAFT WILL BE NEEDED OVER MOST OF LAKE THROUGH THE OVERNIGHT HOURS.
THE WINDS WILL DIE DOWN SIGNIFICANTLY BY TOMORROW AFTERNOON AS HIGH
PRESSURE BUILDS OVER THE LAKE. EXPECT CONDITIONS TO REMAIN BELOW
SMALL CRAFT ADVISORY CRITERIA THROUGH THE WEEKEND AS HIGH PRESSURE
WILL REMAIN OVER THE LAKE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 AM EST TUESDAY FOR LEZ145>149.
SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR
LEZ142>144.
&&
$$
SYNOPSIS...ABE
NEAR TERM...ABE/TK
SHORT TERM...ABE
LONG TERM...MULLEN
AVIATION...OUDEMAN
MARINE...DJB
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
635 PM EST MON NOV 12 2012
.SYNOPSIS...
HIGH PRESSURE WILL BEGIN BUILDING INTO THE AREA FROM THE
SOUTHWEST TONIGHT AND THEN MOVE OVER THE AREA TUESDAY AND
WEDNESDAY. THE HIGH PRESSURE CENTER WILL MOVE NORTHEAST OF THE
AREA...BUT WILL CONTINUE TO RIDGE OVER THE AREA THROUGH THE
SECOND HALF OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
UPDATE...ADJUSTED SKY GRIDS TO REFLECT CLEARING MOVING IN FROM THE
WEST BUT ALSO INCLUDED WRAP AROUND APPROACHING FROM THE WEST.
MODELS DO TAKE MOST OF THIS MOISTURE NORTH OF THE AREA HOWEVER DO
BELIEVE IT GETS INTO THE NORTHWEST COUNTIES LATE THIS EVENING AND
THE REMAINDER OF THE NORTHERN COUNTIES OVERNIGHT.
PREVIOUS...THE COLD FRONT THAT MOVED THROUGH THE AREA TODAY IS
MOVING OUT OF THE FORECAST AREA AS OF 20Z. RAIN WILL CONTINUE
ESPECIALLY ACROSS THE EASTERN HALF OF THE AREA THROUGH THE
REMAINDER OF THE AFTERNOON AND EVENING. MEANWHILE...THERE IS A
SHARP CUTOFF TO BOTH PRECIP AND CLOUDS ACROSS THE WEST WITH
SATELLITE SHOWING CLEARING MOVING INTO NW OH ALREADY THIS
AFTERNOON. OBS HAVE SHOWN A MIX OF RAIN AND SNOW ACROSS WESTERN
COUNTIES BUT RAIN ELSEWHERE. MADE ONLY SMALL ADJUSTMENTS TO POPS
THROUGH EARLY TONIGHT WITH THE RAIN CONTINUING TO PUSH EASTWARD
AND DECREASING POPS FROM WEST TO EAST. WITH THAT MENTION ONLY CHC
POPS ACROSS THE WEST FOR EARLY TONIGHT...THEN DRY AFTER MIDNIGHT.
ONCE THIS AREA OF SHOWERS DEPARTS TO THE EAST THE FOCUS WILL BE ON
LAKE EFFECT SNOW SHOWERS. WITH H850 TEMPS DROPPING DOWN TO -8C OR
SO AND INVERSIONS SHOWN ON BUFKIT SOUNDING STILL A BIT HIGH
EXPECTING LINGERING CLOUDS WITH WEST WINDS ACROSS NE OH AND NW PA
AFTER MIDNIGHT TONIGHT. THINKING THAT WITH THE AMOUNT OF DRIER AIR
BUILDING IN THIS WILL LIMIT LAKE EFFECT SNOW DEVELOPMENT AND WILL
HAVE TO WAIT FOR SOME ADDITIONAL SUPPORT LATE OVERNIGHT.
WATER VAPOR AND MODELS SHOWING SHARPER UPPER TROUGH THAT IS
EXPECTED TO SWING ACROSS THE SOUTHERN GREAT LAKES LATE OVERNIGHT
AND TUESDAY MORNING. EXPECTING THIS TO HELP IN GETTING SOME LAKE
EFFECT SNOW ACROSS NE OH AND NW PA. ELSEWHERE EXPECTING PARTLY
CLOUDY SKIES. USED A BLEND OF MET AND MAV TEMPS WITH HRRR TRENDS
IN THE VERY SHORT TERM ON HOURLY TEMPS.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY NIGHT/...
GUIDANCE POPS NOT INDICATING MUCH WITH LAKE EFFECT SNOW
SHOWERS...BUT WENT WITH AT LEAST HIGH CHC POPS ACROSS NE OH AND NW
PA TUESDAY MORNING. WITH THE WEST FLOW NOT EXPECTING MUCH ACROSS
GREATER CLEVELAND AREA...WITH BEST ACCUMS STRETCHING FROM CENTRAL
ASHTABULA COUNTY INTO INTERIOR ERIE COUNTY. THINKING FURTHER SOUTH
THROUGH CRAWFORD COUNTIES AMOUNTS WILL DIMINISH. BETTER SFC
CONVERGENCE OFF THE LAKE APPEARS TO BE IN THIS AREA ALSO. OVERALL
THOUGH THINKING ACCUMS WILL RANGE AROUND AN INCH OR SO ACROSS
INTERIOR NW PA TO LESS THAN AN INCH BACK INTO FAR NE OH COUNTIES.
BY AFTERNOON THE TROUGH PUSHES TO THE EAST AND DRIER AIR OVERCOMES
THE LAKE EFFECT POTENTIAL. SOME LINGERING CLOUDS AND PERHAPS SOME
FLURRIES POSSIBLE ACROSS HIGHER ELEVATIONS OF NW PA...BUT NOT
EXPECTING ANY FURTHER ACCUMS. FOR THE REMAINDER OF THE AREA HIGH
PRESSURE INFLUENCE WILL HELP ALLOW FOR SUNSHINE. TEMPS EXPECTED TO
RANGE IN MID TO UPPER 30S ACROSS THE NORTHEAST WITH CLOUDS AND AM
SNOW SHOWERS...TO LOWER 40S ACROSS THE SOUTH AND WEST.
FROM TUESDAY NIGHT THROUGH THURSDAY NIGHT HIGH PRESSURE IS
EXPECTED TO BE IN CONTROL ACROSS THE AREA WITH DRY CONDITIONS.
SOME ISSUES WITH CLOUD COVER THROUGH THE PERIOD AS MODELS
CONTINUING TO SHOW SOME WEAK UPPER TROUGHS MOVING THROUGH THE
UPPER FLOW DURING THE PERIOD. DESPITE THAT MAINLY QUIET WEATHER
WITH TEMPS TRENDING TOWARD NORMAL ARE EXPECTED. LEANED TOWARD A
BLEND OF MET MAV AND MEX NUMBER THROUGH THE PERIOD AS SEEING NO
REASON TO DEVIATE MUCH WITH HIGH PRESSURE INFLUENCE.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
HIGH PRESSURE WILL BE THE DOMINANT FEATURE THROUGH THE EXTENDED EVEN
AS THE CENTER OF IT DRIFTS INTO EASTERN QUEBEC PROVINCE. SO AT THIS
POINT WE EXPECT TO SEE DRY CONDITIONS. THERE MAY BE A SLIGHT
INCREASE IN CLOUD COVER ON SUNDAY AS A STORM SYSTEM TAKES SHAPE OFF
THE MIDDLE ATLANTIC COAST. OTHERWISE EXPECT TO SEE TEMPERATURES NEAR
TO SLIGHTLY BELOW AVERAGE THROUGH THE PERIOD.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
COLD FRONT IS EAST OF KERI. PRECIP SHIELD EXTENDS BACK TO KCGF AND
KBJJ AS OF 23Z AND WILL CONTINUE TO SHIFT EAST THIS EVENING. RIGHT
BEFORE THE PRECIP ENDS THERE MAY BE SOME SN/RA MIX...BUT NOT
SIGNIFICANT ENOUGH TO INCLUDE. AS THE PRECIP ENDS THE VSBY AND
CIGS IMPROVE TO VFR OR HIGH END MVFR AND WINDS SHIFT FROM THE WEST
TO THE SOUTHWEST. THERE WILL EVEN BE A PERIOD OF CLEARING FOR
KFDY. THE REST OF THE AREA WILL SIT AT VFR/MVFR FOR SEVERAL HOURS
TONIGHT. A SECONDARY TROUGH WILL SWING ACROSS THE EASTERN GREAT
LAKES FOR THE SECOND HALF OF THE NIGHT/TUESDAY MORNING BRINGING
MVFR CIGS. THE BEST MOISTURE STAYS TO OUR NORTH...BUT IT WILL BE
COLD ENOUGH FOR SOME LAKE EFFECT WITH THE TROUGH. WILL MENTION A
SNRA MIX FOR ERIE IN A TEMPO...BUT THAT IS IT. FORECAST SOUNDING
PROFILES ARE NOT SUGGESTING MUCH WITH THE LACK OF DEEPER
MOISTURE. WINDS SHIFT TO THE NORTHWEST TUESDAY AFTERNOON. HIGH
PRESSURE FOLLLOWS FOR TUESDAY NIGHT.
OUTLOOK...SOME NON-VFR POSSIBLE FRIDAY.
&&
.MARINE...
THE COLD FRONT IS JUST EAST OF THE FORECAST AREA. WINDS DIE DOWN
BEHIND THE FRONT BUT AS THE MUCH COLDER AIR MOVES OVER THE LAKE
INCREASED MIXING WILL OCCUR OVER THE LAKE. THE 850MB TEMPS FORECAST
TO DIP TO MINUS 10C BY DAYBREAK TUESDAY. AS A RESULT THE SMALL
CRAFT WILL BE NEEDED OVER MOST OF LAKE THROUGH THE OVERNIGHT HOURS.
THE WINDS WILL DIE DOWN SIGNIFICANTLY BY TOMORROW AFTERNOON AS HIGH
PRESSURE BUILDS OVER THE LAKE. EXPECT CONDITIONS TO REMAIN BELOW
SMALL CRAFT ADVISORY CRITERIA THROUGH THE WEEKEND AS HIGH PRESSURE
WILL REMAIN OVER THE LAKE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 AM EST TUESDAY FOR LEZ145>149.
SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR
LEZ142>144.
&&
$$
SYNOPSIS...ABE
NEAR TERM...ABE/TK
SHORT TERM...ABE
LONG TERM...MULLEN
AVIATION...OUDEMAN
MARINE...DJB
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
631 PM EST MON NOV 12 2012
.SYNOPSIS...
HIGH PRESSURE WILL BEGIN BUILDING INTO THE AREA FROM THE
SOUTHWEST TONIGHT AND THEN MOVE OVER THE AREA TUESDAY AND
WEDNESDAY. THE HIGH PRESSURE CENTER WILL MOVE NORTHEAST OF THE
AREA...BUT WILL CONTINUE TO RIDGE OVER THE AREA THROUGH THE
SECOND HALF OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
THE COLD FRONT THAT MOVED THROUGH THE AREA TODAY IS MOVING OUT OF
THE FORECAST AREA AS OF 20Z. RAIN WILL CONTINUE ESPECIALLY ACROSS
THE EASTERN HALF OF THE AREA THROUGH THE REMAINDER OF THE
AFTERNOON AND EVENING. MEANWHILE...THERE IS A SHARP CUTOFF TO BOTH
PRECIP AND CLOUDS ACROSS THE WEST WITH SATELLITE SHOWING CLEARING
MOVING INTO NW OH ALREADY THIS AFTERNOON. OBS HAVE SHOWN A MIX OF
RAIN AND SNOW ACROSS WESTERN COUNTIES BUT RAIN ELSEWHERE. MADE
ONLY SMALL ADJUSTMENTS TO POPS THROUGH EARLY TONIGHT WITH THE RAIN
CONTINUING TO PUSH EASTWARD AND DECREASING POPS FROM WEST TO EAST.
WITH THAT MENTION ONLY CHC POPS ACROSS THE WEST FOR EARLY
TONIGHT...THEN DRY AFTER MIDNIGHT.
ONCE THIS AREA OF SHOWERS DEPARTS TO THE EAST THE FOCUS WILL BE ON
LAKE EFFECT SNOW SHOWERS. WITH H850 TEMPS DROPPING DOWN TO -8C OR
SO AND INVERSIONS SHOWN ON BUFKIT SOUNDING STILL A BIT HIGH
EXPECTING LINGERING CLOUDS WITH WEST WINDS ACROSS NE OH AND NW PA
AFTER MIDNIGHT TONIGHT. THINKING THAT WITH THE AMOUNT OF DRIER AIR
BUILDING IN THIS WILL LIMIT LAKE EFFECT SNOW DEVELOPMENT AND WILL
HAVE TO WAIT FOR SOME ADDITIONAL SUPPORT LATE OVERNIGHT.
WATER VAPOR AND MODELS SHOWING SHARPER UPPER TROUGH THAT IS
EXPECTED TO SWING ACROSS THE SOUTHERN GREAT LAKES LATE OVERNIGHT
AND TUESDAY MORNING. EXPECTING THIS TO HELP IN GETTING SOME LAKE
EFFECT SNOW ACROSS NE OH AND NW PA. ELSEWHERE EXPECTING PARTLY
CLOUDY SKIES. USED A BLEND OF MET AND MAV TEMPS WITH HRRR TRENDS
IN THE VERY SHORT TERM ON HOURLY TEMPS.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY NIGHT/...
GUIDANCE POPS NOT INDICATING MUCH WITH LAKE EFFECT SNOW
SHOWERS...BUT WENT WITH AT LEAST HIGH CHC POPS ACROSS NE OH AND NW
PA TUESDAY MORNING. WITH THE WEST FLOW NOT EXPECTING MUCH ACROSS
GREATER CLEVELAND AREA...WITH BEST ACCUMS STRETCHING FROM CENTRAL
ASHTABULA COUNTY INTO INTERIOR ERIE COUNTY. THINKING FURTHER SOUTH
THROUGH CRAWFORD COUNTIES AMOUNTS WILL DIMINISH. BETTER SFC
CONVERGENCE OFF THE LAKE APPEARS TO BE IN THIS AREA ALSO. OVERALL
THOUGH THINKING ACCUMS WILL RANGE AROUND AN INCH OR SO ACROSS
INTERIOR NW PA TO LESS THAN AN INCH BACK INTO FAR NE OH COUNTIES.
BY AFTERNOON THE TROUGH PUSHES TO THE EAST AND DRIER AIR OVERCOMES
THE LAKE EFFECT POTENTIAL. SOME LINGERING CLOUDS AND PERHAPS SOME
FLURRIES POSSIBLE ACROSS HIGHER ELEVATIONS OF NW PA...BUT NOT
EXPECTING ANY FURTHER ACCUMS. FOR THE REMAINDER OF THE AREA HIGH
PRESSURE INFLUENCE WILL HELP ALLOW FOR SUNSHINE. TEMPS EXPECTED TO
RANGE IN MID TO UPPER 30S ACROSS THE NORTHEAST WITH CLOUDS AND AM
SNOW SHOWERS...TO LOWER 40S ACROSS THE SOUTH AND WEST.
FROM TUESDAY NIGHT THROUGH THURSDAY NIGHT HIGH PRESSURE IS
EXPECTED TO BE IN CONTROL ACROSS THE AREA WITH DRY CONDITIONS.
SOME ISSUES WITH CLOUD COVER THROUGH THE PERIOD AS MODELS
CONTINUING TO SHOW SOME WEAK UPPER TROUGHS MOVING THROUGH THE
UPPER FLOW DURING THE PERIOD. DESPITE THAT MAINLY QUIET WEATHER
WITH TEMPS TRENDING TOWARD NORMAL ARE EXPECTED. LEANED TOWARD A
BLEND OF MET MAV AND MEX NUMBER THROUGH THE PERIOD AS SEEING NO
REASON TO DEVIATE MUCH WITH HIGH PRESSURE INFLUENCE.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
HIGH PRESSURE WILL BE THE DOMINANT FEATURE THROUGH THE EXTENDED EVEN
AS THE CENTER OF IT DRIFTS INTO EASTERN QUEBEC PROVINCE. SO AT THIS
POINT WE EXPECT TO SEE DRY CONDITIONS. THERE MAY BE A SLIGHT
INCREASE IN CLOUD COVER ON SUNDAY AS A STORM SYSTEM TAKES SHAPE OFF
THE MIDDLE ATLANTIC COAST. OTHERWISE EXPECT TO SEE TEMPERATURES NEAR
TO SLIGHTLY BELOW AVERAGE THROUGH THE PERIOD.
&&
.AVIATION /23Z MONDAY THROUGH SATURDAY/...
COLD FRONT IS EAST OF KERI. PRECIP SHIELD EXTENDS BACK TO KCGF AND
KBJJ AS OF 23Z AND WILL CONTINUE TO SHIFT EAST THIS EVENING. RIGHT
BEFORE THE PRECIP ENDS THERE MAY BE SOME SN/RA MIX...BUT NOT
SIGNIFICANT ENOUGH TO INCLUDE. AS THE PRECIP ENDS THE VSBY AND
CIGS IMPROVE TO VFR OR HIGH END MVFR AND WINDS SHIFT FROM THE WEST
TO THE SOUTHWEST. THERE WILL EVEN BE A PERIOD OF CLEARING FOR
KFDY. THE REST OF THE AREA WILL SIT AT VFR/MVFR FOR SEVERAL HOURS
TONIGHT. A SECONDARY TROUGH WILL SWING ACROSS THE EASTERN GREAT
LAKES FOR THE SECOND HALF OF THE NIGHT/TUESDAY MORNING BRINGING
MVFR CIGS. THE BEST MOISTURE STAYS TO OUR NORTH...BUT IT WILL BE
COLD ENOUGH FOR SOME LAKE EFFECT WITH THE TROUGH. WILL MENTION A
SNRA MIX FOR ERIE IN A TEMPO...BUT THAT IS IT. FORECAST SOUNDING
PROFILES ARE NOT SUGGESTING MUCH WITH THE LACK OF DEEPER
MOISTURE. WINDS SHIFT TO THE NORTHWEST TUESDAY AFTERNOON. HIGH
PRESSURE FOLLLOWS FOR TUESDAY NIGHT.
OUTLOOK...SOME NON-VFR POSSIBLE FRIDAY.
&&
.MARINE...
THE COLD FRONT IS JUST EAST OF THE FORECAST AREA. WINDS DIE DOWN
BEHIND THE FRONT BUT AS THE MUCH COLDER AIR MOVES OVER THE LAKE
INCREASED MIXING WILL OCCUR OVER THE LAKE. THE 850MB TEMPS FORECAST
TO DIP TO MINUS 10C BY DAYBREAK TUESDAY. AS A RESULT THE SMALL
CRAFT WILL BE NEEDED OVER MOST OF LAKE THROUGH THE OVERNIGHT HOURS.
THE WINDS WILL DIE DOWN SIGNIFICANTLY BY TOMORROW AFTERNOON AS HIGH
PRESSURE BUILDS OVER THE LAKE. EXPECT CONDITIONS TO REMAIN BELOW
SMALL CRAFT ADVISORY CRITERIA THROUGH THE WEEKEND AS HIGH PRESSURE
WILL REMAIN OVER THE LAKE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 AM EST TUESDAY FOR LEZ145>149.
SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR
LEZ142>144.
&&
$$
SYNOPSIS...ABE
NEAR TERM...ABE/TK
SHORT TERM...ABE
LONG TERM...MULLEN
AVIATION...OUDEMAN
MARINE...DJB
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
608 AM EST SUN NOV 11 2012
.SYNOPSIS...
LOW PRESSURE OVER MINNESOTA WILL CONTINUE NORTH INTO CANADA TODAY.
A STRONG COLD FRONT ASSOCIATED WITH THIS LOW WILL SWEEP EAST
ACROSS THE LOCAL AREA ON MONDAY. HIGH PRESSURE WILL THEN BUILD
OVER THE REGION FOR THE REMAINDER OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
MADE SOME MINOR ADJUSTMENTS TO THE CLOUD COVER OTHERWISE NO
CHANGES.
PREVIOUS...SOUTHERLY WINDS HAVE STAYED UP OVERNIGHT AND THIS HAS
KEPT TEMPS IN THE MIDDLE 50S MOST AREAS. THE AREA IS NOW
COMFORTABLY IN THE WARM SECTOR AND SEE NO REASON WHY TEMPS WON`T
BE A FEW DEGREES WARMER THAN THEY WERE ON SATURDAY. SOME HIGH
CLOUDS WILL OVERSPREAD THE AREA TODAY BUT THESE SHOULD BE FAIRLY
THIN. HAVE GONE A COUPLE DEGREES ABOVE GUIDANCE AND MUCH OF THE
AREA WILL HAVE A SHOT AT REACHING 70 DEGREES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
NOT MUCH CHANGE TO THE SHORT TERM PERIOD THIS MORNING. MODELS NOW
IN GOOD AGREEMENT BRINGING A STRONG COLD FRONT ACROSS THE AREA ON
MONDAY. THIS FRONT SHOULD REACH THE WESTERN TIP OF THE AREA AROUND
DAYBREAK AND MOVE INTO NW PA BY EARLY AFTERNOON. WILL SEE A LINE
OF SHOWERS ALONG AND BEHIND THIS FRONT AND THE ENTIRE AREA WILL
SEE A SEVERAL HOUR PERIOD OF PRECIPITATION. GIVEN THE TIME OF
DAY...NOT EXPECTING MUCH IF ANY THUNDER WITH THE SHOWERS.
DEWPOINTS COULD POOL INTO THE 50S IN NW PA AND FAR NE OH BEFORE
THE FRONT ARRIVES AND IF ANY AREA HAS A SHOT FOR THUNDER IT COULD
BE THERE. EXPECT CLOSE TO A HALF INCH OF PRECIP MOST AREAS. NEXT
QUESTION IS HOW QUICK THE PRECIP WILL END. IT NOW APPEARS THAT NW
OH AND PORTIONS OF N-CENTRAL OH WILL BE DRY BY LATE TOMORROW
AFTERNOON. HAVE FINE TUNED PRECIP CHANCES. REALISTICALLY...ONLY
ABOUT THE EAST THIRD OF THE AREA HAS A SHOT OF MEASURABLE PRECIP
AFTER 00Z TUE. BY THAT TIME LOW LEVEL THICKNESSES COULD GET COLD
ENOUGH FOR SNOW SHOWERS OR MIXED PRECIP TO THE EAST OF KCLE. ANY
PRECIP THAT FALLS AFTER DARK SHOULD BE FAIRLY LIGHT AND NOT
EXPECTING ANY ACCUMS. BY DAYBREAK TUESDAY 850 MB TEMPS WILL BE
AROUND NEG 8 SO LAKE EFFECT CLOUDS ARE LIKELY IN THE WESTERLY
FLOW. COULD ALSO SEE A FEW SHOWERS EVEN THOUGH THE LOWER
ATMOSPHERE WILL BE FAIRLY DRY. RIDGING WILL MOVE INTO THE AREA
LATER TUESDAY AND THIS SHOULD END THE PRECIP THREAT. TEMPS COULD
SNEAK INTO THE 60S OVER EASTERN AREAS MONDAY AHEAD OF THE FRONT.
THE REST OF THE PERIOD WILL SEE BELOW NORMAL TEMPS. HAVE STAYED
PRETTY CLOSE TO GUIDANCE MOST PERIODS.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
MODELS CONTINUE TO BE IN REASONABLE AGREEMENT IN THE LONG TERM WITH
HIGH PRESSURE ANCHORED OVER THE GREAT LAKES. MODELS MOVE LOW
PRESSURE SYSTEM ACROSS THE LOWER TENNESSEE VALLEY LATE IN THE WEEK
AND THEN UP THE EAST COAST THIS WEEKEND. ALTHOUGH EXACT TRACK AND
TIMING OF LOW OFF SOMEWHAT BOTH MODELS HAVE THE LOW OFF THE VIRGINIA
COAST BY SUNDAY AFTERNOON. AT THIS POINT HIGH SEEMS STRONG ENOUGH
THAT WILL KEEP FORECAST DRY THROUGH THE ENTIRE FORECAST PERIOD.
TEMPS CONTINUE TO SHOW A VERY GRADUAL WARMING TREND.
&&
.AVIATION /11Z SUNDAY THROUGH THURSDAY/...
LOOKING AT WINDS AND TEMPS...BEST FIT FOR WARM FRONT PLACEMENT
TAKES IT FROM CENTRAL LWR MI ESE ACROSS LAKE ERIE INTO NERN OHIO.
WINDS AT KERI ARE FRONT 060 DEGREES AND KCLE AND KYNG HAVE BACKED
10 TO 30 DEGREES OVER THE PAST COUPLE HOURS SO FRONT MAY BE
WAFFLING A BIT INTO THE AREA. A QUICK LOOK AT THE HRRR HIGH REZ
WIND FORECAST SUGGESTS THIS STOPS AND REVERSES OVER THE NEXT
COUPLE HOURS TURNING WINDS AT KERI BACK TO SOUTHERLY. HAVE ALSO
SEEN DEVELOPMENT OF A CIG AROUND 45 HUNDRED FEET AT KERI AND
SATELLITE SHOWS A SIMILAR DECK DEVELOPING IN VICINITY OF KCLE AS
WELL. WILL CARRY THIS FOR THE NEXT FEW HOURS BUT WITH THE WARM
FRONT BEGINNING TO MOVE NORTH AGAIN WILL NOT CARRY THROUGH THE
NIGHT. OTHER THAN THAT EXPECT ONLY CONVECTIVE DEBRIS CLOUDS
100-120 FEET TO AFFECT TERMINALS OVERNIGHT. SUNDAY...THROUGH THE
DAY EXPECT VFR CONDITIONS BUT WINDS WILL INCREASE TO AROUND 15
KNOTS GUSTING INTO THE MID 20 KNOT RANGE KCLE AND POINTS WEST.
FURTHER EAST GUSTS TO NEAR 20.
OUTLOOK...NON-VFR DEVELOPING IN SHOWERS MONDAY THROUGH MONDAY
EVENING ALONG WITH GUSTY WINDS...LINGERING NON VFR NE OH/NW PA ON
TUESDAY.
&&
.MARINE...
SOUTH FLOW WILL BECOME BREEZY THIS AFTERNOON...BUT AS COLD AS THE
LAKE IS DO NOT THINK A LOT OF THE WIND WILL MIX DOWN TO THE LAKE
ITSELF. THEREFORE WILL NOT GO WITH A SMALL CRAFT ADVISORY TODAY. A
SMALL CRAFT WILL LIKELY BE NEEDED TONIGHT. MODELS CONTINUE TO BE IN
GOOD AGREEMENT ON THE TIMING OF THE STRONG COLD FRONT MONDAY. WINDS
TURN TO THE WEST AND INCREASE TO 30 KNOTS MONDAY AS THE FRONT MOVES
ACROSS THE LAKE. THE 850MB TEMPS DIP TO MINUS 10C BY TUESDAY.
SMALL CRAFT LIKELY UNTIL LATE TUESDAY AS HIGH PRESSURE MOVES OVER
THE LAKE. AFTER THAT HIGH PRESSURE WILL BE DOMINATE FEATURE INTO
NEXT WEEKEND.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KUBINA
NEAR TERM...KUBINA
SHORT TERM...KUBINA
LONG TERM...DJB
AVIATION...DJB
MARINE...DJB
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
309 AM EST SUN NOV 11 2012
.SYNOPSIS...
LOW PRESSURE OVER MINNESOTA WILL CONTINUE NORTH INTO CANADA TODAY.
A STRONG COLD FRONT ASSOCIATED WITH THIS LOW WILL SWEEP EAST
ACROSS THE LOCAL AREA ON MONDAY. HIGH PRESSURE WILL THEN BUILD
OVER THE REGION FOR THE REMAINDER OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
SOUTHERLY WINDS HAVE STAYED UP OVERNIGHT AND THIS HAS KEPT TEMPS
IN THE MIDDLE 50S MOST AREAS. THE AREA IS NOW COMFORTABLY IN THE
WARM SECTOR AND SEE NO REASON WHY TEMPS WON`T BE A FEW DEGREES
WARMER THAN THEY WERE ON SATURDAY. SOME HIGH CLOUDS WILL
OVERSPREAD THE AREA TODAY BUT THESE SHOULD BE FAIRLY THIN. HAVE
GONE A COUPLE DEGREES ABOVE GUIDANCE AND MUCH OF THE AREA WILL
HAVE A SHOT AT REACHING 70 DEGREES.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
NOT MUCH CHANGE TO THE SHORT TERM PERIOD THIS MORNING. MODELS NOW
IN GOOD AGREEMENT BRINGING A STRONG COLD FRONT ACROSS THE AREA ON
MONDAY. THIS FRONT SHOULD REACH THE WESTERN TIP OF THE AREA AROUND
DAYBREAK AND MOVE INTO NW PA BY EARLY AFTERNOON. WILL SEE A LINE
OF SHOWERS ALONG AND BEHIND THIS FRONT AND THE ENTIRE AREA WILL
SEE A SEVERAL HOUR PERIOD OF PRECIPITATION. GIVEN THE TIME OF
DAY...NOT EXPECTING MUCH IF ANY THUNDER WITH THE SHOWERS.
DEWPOINTS COULD POOL INTO THE 50S IN NW PA AND FAR NE OH BEFORE
THE FRONT ARRIVES AND IF ANY AREA HAS A SHOT FOR THUNDER IT COULD
BE THERE. EXPECT CLOSE TO A HALF INCH OF PRECIP MOST AREAS. NEXT
QUESTION IS HOW QUICK THE PRECIP WILL END. IT NOW APPEARS THAT NW
OH AND PORTIONS OF N-CENTRAL OH WILL BE DRY BY LATE TOMORROW
AFTERNOON. HAVE FINE TUNED PRECIP CHANCES. REALISTICALLY...ONLY
ABOUT THE EAST THIRD OF THE AREA HAS A SHOT OF MEASURABLE PRECIP
AFTER 00Z TUE. BY THAT TIME LOW LEVEL THICKNESSES COULD GET COLD
ENOUGH FOR SNOW SHOWERS OR MIXED PRECIP TO THE EAST OF KCLE. ANY
PRECIP THAT FALLS AFTER DARK SHOULD BE FAIRLY LIGHT AND NOT
EXPECTING ANY ACCUMS. BY DAYBREAK TUESDAY 850 MB TEMPS WILL BE
AROUND NEG 8 SO LAKE EFFECT CLOUDS ARE LIKELY IN THE WESTERLY
FLOW. COULD ALSO SEE A FEW SHOWERS EVEN THOUGH THE LOWER
ATMOSPHERE WILL BE FAIRLY DRY. RIDGING WILL MOVE INTO THE AREA
LATER TUESDAY AND THIS SHOULD END THE PRECIP THREAT. TEMPS COULD
SNEAK INTO THE 60S OVER EASTERN AREAS MONDAY AHEAD OF THE FRONT.
THE REST OF THE PERIOD WILL SEE BELOW NORMAL TEMPS. HAVE STAYED
PRETTY CLOSE TO GUIDANCE MOST PERIODS.
&&
.LONG TERM /THURSDAY THROUGH SATURDAY/...
MODELS CONTINUE TO BE IN REASONABLE AGREEMENT IN THE LONG TERM WITH
HIGH PRESSURE ANCHORED OVER THE GREAT LAKES. MODELS MOVE LOW
PRESSURE SYSTEM ACROSS THE LOWER TENNESSEE VALLEY LATE IN THE WEEK
AND THEN UP THE EAST COAST THIS WEEKEND. ALTHOUGH EXACT TRACK AND
TIMING OF LOW OFF SOMEWHAT BOTH MODELS HAVE THE LOW OFF THE VIRGINIA
COAST BY SUNDAY AFTERNOON. AT THIS POINT HIGH SEEMS STRONG ENOUGH
THAT WILL KEEP FORECAST DRY THROUGH THE ENTIRE FORECAST PERIOD.
TEMPS CONTINUE TO SHOW A VERY GRADUAL WARMING TREND.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
LOOKING AT WINDS AND TEMPS...BEST FIT FOR WARM FRONT PLACEMENT
TAKES IT FROM CENTRAL LWR MI ESE ACROSS LAKE ERIE INTO NERN OHIO.
WINDS AT KERI ARE FRONT 060 DEGREES AND KCLE AND KYNG HAVE BACKED
10 TO 30 DEGREES OVER THE PAST COUPLE HOURS SO FRONT MAY BE
WAFFLING A BIT INTO THE AREA. A QUICK LOOK AT THE HRRR HIGH REZ
WIND FORECAST SUGGESTS THIS STOPS AND REVERSES OVER THE NEXT
COUPLE HOURS TURNING WINDS AT KERI BACK TO SOUTHERLY. HAVE ALSO
SEEN DEVELOPMENT OF A CIG AROUND 45 HUNDRED FEET AT KERI AND
SATELLITE SHOWS A SIMILAR DECK DEVELOPING IN VICINITY OF KCLE AS
WELL. WILL CARRY THIS FOR THE NEXT FEW HOURS BUT WITH THE WARM
FRONT BEGINNING TO MOVE NORTH AGAIN WILL NOT CARRY THROUGH THE
NIGHT. OTHER THAN THAT EXPECT ONLY CONVECTIVE DEBRIS CLOUDS
100-120 FEET TO AFFECT TERMINALS OVERNIGHT. SUNDAY...THROUGH THE
DAY EXPECT VFR CONDITIONS BUT WINDS WILL INCREASE TO AROUND 15
KNOTS GUSTING INTO THE MID 20 KNOT RANGE KCLE AND POINTS WEST.
FURTHER EAST GUSTS TO NEAR 20.
OUTLOOK...NON-VFR DEVELOPING IN SHOWERS MONDAY THROUGH MONDAY
EVENING ALONG WITH GUSTY WINDS...LINGERING NON VFR NE OH/NW PA ON
TUESDAY.
&&
.MARINE...
SOUTH FLOW WILL BECOME BREEZY THIS AFTERNOON...BUT AS COLD AS THE
LAKE IS DO NOT THINK A LOT OF THE WIND WILL MIX DOWN TO THE LAKE
ITSELF. THEREFORE WILL NOT GO WITH A SMALL CRAFT ADVISORY TODAY. A
SMALL CRAFT WILL LIKELY BE NEEDED TONIGHT. MODELS CONTINUE TO BE IN
GOOD AGREEMENT ON THE TIMING OF THE STRONG COLD FRONT MONDAY. WINDS
TURN TO THE WEST AND INCREASE TO 30 KNOTS MONDAY AS THE FRONT MOVES
ACROSS THE LAKE. THE 850MB TEMPS DIP TO MINUS 10C BY TUESDAY.
SMALL CRAFT LIKELY UNTIL LATE TUESDAY AS HIGH PRESSURE MOVES OVER
THE LAKE. AFTER THAT HIGH PRESSURE WILL BE DOMINATE FEATURE INTO
NEXT WEEKEND.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...NONE.
&&
$$
SYNOPSIS...KUBINA
NEAR TERM...KUBINA
SHORT TERM...KUBINA
LONG TERM...DJB
AVIATION...TK
MARINE...DJB
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
1035 AM CST SUN NOV 11 2012
.DISCUSSION.../ISSUED AT 1035 AM CST/
EARLIER FORECAST WAS PRETTY GOOD. HAVE BRIGHTENED UP SKIES A LITTLE
AND HELD TEMPERATURES DOWN A TAD BUT PRETTY SMALL CHANGES. EARLIER
WINDS ARE LOOKING GOOD...WINDY BUT A LITTLE BELOW ADVISORY CRITERIA.
EARLY OUTLOOK FOR THREAT OF MINIMAL LIGHT SNOW LOOKS OK BUT IT MAY
BE JUST SOME FLURRIES.
&&
.AVIATION.../FOR THE 12Z TAF ISSUANCE/
NAM AND RUC SHOW A STOUT INVERSION AROUND 900MB UNTIL AROUND 9-10 AM
LOCAL TIME AT FSD AND SUX WITH DRYING BELOW THE INVERSION. HON
SOUNDINGS SHOW THE INVERSION LIFTING AROUND 7-8AM LOCAL. WILL START
RAISING CIGS AROUND THE AFOREMENTIONED TIMES. SOME BREAKS IN THE
CLOUDS WILL BE POSSIBLE LATER THIS MORNING BUT ANOTHER SLUG OF
MOISTURE RETURNS AS WELL AS AN UPPER LEVEL TROF AND CLOUDS WILL FILL
BACK IN IN THE AFTERNOON THROUGH THE EVENING WITH VFR EXPECTED.
GUSTY WIND WILL CONTINUE THROUGH THE DAY AND INTO THE EARLY EVENING
WITH GUSTS STARTING TO SUBSIDE A FEW HOURS AFTER SUNSET.
&&
.PREV DISCUSSION.../ISSUED AT 331 AM CST/
MAJOR TROUGH MOVING THROUGH THIS MORNING WITH SUBSIDENCE BECOMING
STRONGER THROUGH THE DAY. OUTSIDE OF A FEW FLURRIES NOT REALLY
EXPECTING MUCH IN THE WAY OF PRECIPITATION. VERY COLD AIR POURING
INTO THE REGION WITH WIND CHILL VALUES INT HE SINGLE DIGITS WEST OF
INTERSTATE 29. VERY LITTLE REBOUND TODAY WITH CONTINUED COLD AIR
ADVECTION AND SOME CLOUD COVER TO SHAKE OFF SO ONLY EXPECTING A
REBOUND OF 5 TO 8 DEGREES FROM THIS MORNINGS LOW TEMPERATURE.
SO...LOWERED HIGHS A COUPLE OF DEGREES...ESPECIALLY WEST WHERE A
LITTLE ACCUMULATING SNOW MAY HAVE FALLEN.
JUST AS THE CLOUDS SCOUR OUT FROM SOUTH TO NORTH TODAY ADDITIONAL
CLOUD COVER WILL BUILD SOUTH FROM NORTH DAKOTA AS THE COLD CORE LOW
BUILDS SOUTHWARD. WILL CONTINUE A SMALL CHANCE FOR SNOWFALL NORTH OF
INTERSTATE 90 AS THIS DOES SO WITH MODERATELY STEEP LAPSE RATES
DEVELOPING. IF THIS COLD CORE WAS MOVING THROUGH DURING THE DAY
CONFIDENCE IN A FEW SNOW SHOWERS WOULD BE A LITTLE HIGHER. NOT
AIMING TOO LOW WITH CLOUD COVER BUT STILL BELIEVE TEENS TO LOWER 20S
WILL BE COMMON.
BY MONDAY A GOOD MIXING WESTERLY WIND AND DECREASING CLOUD COVER
WILL ALLOW FOR SOME WARMING...AND INCREASED HIGHS JUST A BIT TO
ACCOUNT FOR POTENTIALLY DECENT MIXING CONDITIONS...BUT STILL ONLY IN
THE 30S.
WINDS WILL TURN TO THE SOUTH MONDAY NIGHT INTO TUESDAY ALLOWING FOR
LESS COLD CONDITIONS. LOWS STILL IN THE TEENS TO MID 20S WITH HIGHS
CLIMBING BACK INTO THE 40S. IF THE NAM LOW LEVEL THERMAL FIELD IS A
LITTLE CLOSER AREAS IN THE SOUTHERN CWA COULD CLIMB INTO THE LOWER
50S.
IN THE LATTER PERIODS(WED/SAT)...OVERALL LOOKS FAIRLY QUIET THROUGH
THE PERIOD WITH SPLIT FLOW DEVELOPING EARLY AND SOME HINT OF A WEAK
SOUTHERN STREAM WAVE MOVING IN ON SATURDAY. GENERALLY SPLIT FLOW IS
FAIRLY QUIET SO WILL CONTINUE WITH NO REAL THREAT FOR
PRECIPITATION...EXCEPT CONTINUE THE POP FOR SATURDAYS WEAK WAVE.
OTHERWISE...TEMPERATURES FAIRLY SEASONAL THROUGH THE PERIOD WITH NO
MAJOR COOL DOWNS OR WARM UPS...SO WILL BE SHOOTING FOR HIGHS MAINLY
IN THE 40S TO LOWER 50S AND LOWS IN THE 20S TO LOWER 30S WITH THE
POTENTIAL FOR SOME WARMER LOWS ON SATURDAY MORNING AHEAD OF THE
INCOMING WAVE. /08
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NWS SIOUX FALLS SD
518 AM CST SUN NOV 11 2012
.DISCUSSION.../ISSUED AT 331 AM CST/
MAJOR TROUGH MOVING THROUGH THIS MORNING WITH SUBSIDENCE BECOMING
STRONGER THROUGH THE DAY. OUTSIDE OF A FEW FLURRIES NOT REALLY
EXPECTING MUCH IN THE WAY OF PRECIPITATION. VERY COLD AIR POURING
INTO THE REGION WITH WIND CHILL VALUES INT HE SINGLE DIGITS WEST OF
INTERSTATE 29. VERY LITTLE REBOUND TODAY WITH CONTINUED COLD AIR
ADVECTION AND SOME CLOUD COVER TO SHAKE OFF SO ONLY EXPECTING A
REBOUND OF 5 TO 8 DEGREES FROM THIS MORNINGS LOW TEMPERATURE.
SO...LOWERED HIGHS A COUPLE OF DEGREES...ESPECIALLY WEST WHERE A
LITTLE ACCUMULATING SNOW MAY HAVE FALLEN.
JUST AS THE CLOUDS SCOUR OUT FROM SOUTH TO NORTH TODAY ADDITIONAL
CLOUD COVER WILL BUILD SOUTH FROM NORTH DAKOTA AS THE COLD CORE LOW
BUILDS SOUTHWARD. WILL CONTINUE A SMALL CHANCE FOR SNOWFALL NORTH OF
INTERSTATE 90 AS THIS DOES SO WITH MODERATELY STEEP LAPSE RATES
DEVELOPING. IF THIS COLD CORE WAS MOVING THROUGH DURING THE DAY
CONFIDENCE IN A FEW SNOW SHOWERS WOULD BE A LITTLE HIGHER. NOT
AIMING TOO LOW WITH CLOUD COVER BUT STILL BELIEVE TEENS TO LOWER 20S
WILL BE COMMON.
BY MONDAY A GOOD MIXING WESTERLY WIND AND DECREASING CLOUD COVER
WILL ALLOW FOR SOME WARMING...AND INCREASED HIGHS JUST A BIT TO
ACCOUNT FOR POTENTIALLY DECENT MIXING CONDITIONS...BUT STILL ONLY IN
THE 30S.
WINDS WILL TURN TO THE SOUTH MONDAY NIGHT INTO TUESDAY ALLOWING FOR
LESS COLD CONDITIONS. LOWS STILL IN THE TEENS TO MID 20S WITH HIGHS
CLIMBING BACK INTO THE 40S. IF THE NAM LOW LEVEL THERMAL FIELD IS A
LITTLE CLOSER AREAS IN THE SOUTHERN CWA COULD CLIMB INTO THE LOWER
50S.
IN THE LATTER PERIODS(WED/SAT)...OVERALL LOOKS FAIRLY QUIET THROUGH
THE PERIOD WITH SPLIT FLOW DEVELOPING EARLY AND SOME HINT OF A WEAK
SOUTHERN STREAM WAVE MOVING IN ON SATURDAY. GENERALLY SPLIT FLOW IS
FAIRLY QUIET SO WILL CONTINUE WITH NO REAL THREAT FOR
PRECIPITATION...EXCEPT CONTINUE THE POP FOR SATURDAYS WEAK WAVE.
OTHERWISE...TEMPERATURES FAIRLY SEASONAL THROUGH THE PERIOD WITH NO
MAJOR COOL DOWNS OR WARM UPS...SO WILL BE SHOOTING FOR HIGHS MAINLY
IN THE 40S TO LOWER 50S AND LOWS IN THE 20S TO LOWER 30S WITH THE
POTENTIAL FOR SOME WARMER LOWS ON SATURDAY MORNING AHEAD OF THE
INCOMING WAVE. /08
&&
.AVIATION.../FOR THE 12Z TAF ISSUANCE/
NAM AND RUC SHOW A STOUT INVERSION AROUND 900MB UNTIL AROUND 9-10 AM
LOCAL TIME AT FSD AND SUX WITH DRYING BELOW THE INVERSION. HON
SOUNDINGS SHOW THE INVERSION LIFTING AROUND 7-8AM LOCAL. WILL START
RAISING CIGS AROUND THE AFOREMENTIONED TIMES. SOME BREAKS IN THE
CLOUDS WILL BE POSSIBLE LATER THIS MORNING BUT ANOTHER SLUG OF
MOISTURE RETURNS AS WELL AS AN UPPER LEVEL TROF AND CLOUDS WILL FILL
BACK IN IN THE AFTERNOON THROUGH THE EVENING WITH VFR EXPECTED.
GUSTY WIND WILL CONTINUE THROUGH THE DAY AND INTO THE EARLY EVENING
WITH GUSTS STARTING TO SUBSIDE A FEW HOURS AFTER SUNSET.
&&
.FSD WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
MN...NONE.
IA...NONE.
NE...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
324 PM CST SUN NOV 11 2012
.DISCUSSION...
CF IS THROUGH WACO AND TEMPLE AND HEADED FOR CLL 5-6 PM. RAP AND
LOCAL WRF ARE IN GOOD AGREEMENT THAT THE FRONT WILL REACH IAH
AROUND 9 PM AND THEN NEAR THE COAST AROUND MIDNIGHT. THE CAP HAS
HELD STRONG ACROSS SE TX TODAY...WITH THE ONLY TSTMS NORTH OF THE
AREA SO FAR AND WITHIN THE SVR TSTM WATCH AREA. EXPECT TO SEE SOME
TSTMS DEVELOP ACROSS NORTHERN AREAS DURING THE NEXT COUPLE HOURS
AS THE FRONT APPROACHES. STILL A SLIGHT RISK OF SVR TSTMS ACROSS
NORTHERN AREAS AND THIS THREAT APPEARS TO BE UNTIL AROUND 9
PM...WITH ISOLATED STRONG WIND GUSTS A POSSIBILITY WITH ANY
STRONG/SEVERE STORM THAT DEVELOPS. LOWERED POPS A LITTLE ACROSS
SOUTHWEST AREAS THIS EVENING AS THE CAP MAY BE PROBLEMATIC FOR
PRECIP...EVEN WITH THE BOUNDARY.
PREFER THE GFS FOR THE FORECAST...ALTHOUGH NO SIGNIFICANT
DIFFERENCES BETWEEN THE ECMWF/GFS AS THE GFS HAS TRENDED COLDER
TOWARD THE END OF THE WEEK WITH NW FLOW ALOFT AND ANOTHER
REINFORCING COOL PUSH ON WED BEHIND A SHORT WAVE TROF. STILL DO
NOT THINK WE WILL SEE RAIN WITH THIS DISTURBANCE ACROSS SOUTHERN
AREAS ON TUE NIGHT AS THE ATMOSPHERE IS VERY DRY IN THE LOW-
LEVELS. WE WILL SEE SOME ADDITIONAL MID-LEVEL CLOUD COVER. MADE
SOME COOLER ADJUSTMENTS TO THE FORECAST ESPECIALLY FOR MIN TEMPS
THU...FRI...AND SAT. WILL SEE MIN TEMPS IN THE MID 30S ACROSS
NORTHERN AREAS TUE THROUGH THU MORNINGS.
THE NEXT RAIN CHANCE APPEARS TO BE NEXT WEEKEND AS MOISTURE
RETURNS AND A MID/UPPER TROUGH MOVES ACROSS. 33
&&
.PRELIMINARY POINT TEMPS/POPS...
COLLEGE STATION (CLL) 47 66 37 64 39 / 40 0 0 0 0
HOUSTON (IAH) 56 69 41 66 42 / 60 0 0 0 0
GALVESTON (GLS) 61 71 50 66 49 / 60 0 0 0 0
&&
.AVIATION...
DID NOT MAKE A LOT OF CHANGES WITH THIS 18Z TAF PACKAGE AS TIMING OF
THE COLD FRONT REMAINS ON PACE FOR PASSAGE AT CLL AROUND 00Z THEN TO
THE COAST/GLS BY 08Z. STILL SOME QUESTIONS AS TO THE STRENGTH OF THE
CAP FOR LOCATIONS SOUTH OF I-10 BUT DID KEEP VCTS IN FOR FROPA. VERY
RAPID CLEARING BEHIND THE FRONT WITH VFR AREAWIDE BY SUNRISE. 41
&&
.MARINE...
MODERATE/STRONG ONSHORE WINDS...BUT THE MAIN ISSUE FOR THE AFTERNOON
HAS BEEN THE ELEVATED SEAS. DID RAISE A SMALL CRAFT ADVISORY FOR ALL
OF THE COASTAL WATERS TODAY (AS WELL AS KEEPING AN SCEC FOR BAYS) AS
WE HEAD INTO TONIGHT. WE COULD GET A BRIEF BREAK WITH THESE ELEVATED
WINDS/SEAS JUST AHEAD OF THE FRONT BUT CONDITIONS EXPECTED TO RATCH-
ET BACK UP BY SUNRISE AS THE COLDER AIR MOVES INTO THE MARINE ZONES.
SCA FLAGS MAY NEED TO BE EXTENDED FOR THE BAYS BEHIND THE COLD FRONT
SHOULD THE MODELS VERIFY. HIGH PRESSURE BUILDING IN OVER THE AREA TO
HELP LOWER WINDS/SEAS BY TUES AFTN. 41
&&
.FIRE WEATHER...
SOME ISSUES OF CONCERN REGARDING CONDITIONS IN THE WAKE OF THE FRONT
FOR MON. VERY DRY AIR MOVING DOWN OFF THE PLAINS COULD LOWER MINIMUM
AFTN RH LEVELS TO AROUND 25% FOR MOST INLAND AREAS MON BUT WINDS ARE
LIKELY TO REMAIN LOW (10-15MPH) DURING THIS SAME TIME FRAME. HOWEVER
INTERESTS SHOULD CONTINUE TO MONITOR THE FCST. 41
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...NONE.
GM...SMALL CRAFT SHOULD EXERCISE CAUTION THROUGH TUESDAY AFTERNOON
FOR THE FOLLOWING ZONES: GALVESTON BAY...MATAGORDA BAY...
WATERS FROM FREEPORT TO THE MATAGORDA SHIP CHANNEL OUT 20
NM...WATERS FROM HIGH ISLAND TO FREEPORT OUT 20 NM.
SMALL CRAFT ADVISORY UNTIL 6 PM CST TUESDAY FOR THE FOLLOWING
ZONES: 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...33
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
1149 PM CST SAT NOV 10 2012
.UPDATE...
&&
.AVIATION...
CONVECTION CONTINUES TO DEVELOP ACROSS THE WESTERN PORTIONS OF
THE BIG COUNTRY LATE THIS EVENING...BUT APPEARS THAT THE VAST
MAJORITY WILL TRACK NORTH AND WEST OF ABILENE...KABI. WILL
CONTINUE THE VCTS MENTION...AS THE MAIN AREA OF LIFT LIFTS TO THE
NORTHWEST. PACIFIC FRONT MOVING INTO THE AREA WILL KEEP SOME
CHANCE OF STORMS THROUGH THE OVERNIGHT HOURS...AGAIN...MAINLY NEAR KABI.
OTHERWISE...BREEZE SOUTH WINDS TO CONTINUE OVERNIGHT...AND WILL
LIKELY SEE A FEW STRATUS...BUT MAY ACTUALLY HAVE A HARD TIME
FORMING ANYTHING MORE THAN A BRIEF CIG. COLD FRONT MOVES QUICKLY
THROUGH ON SUNDAY...BRINGING DRIER CONDITIONS ON STRONG WEST WINDS.
&&
.PREV DISCUSSION... /ISSUED 905 PM CST SAT NOV 10 2012/
UPDATE...
NO CHANGES.
DISCUSSION...
SURFACE TROUGH AND COLD FRONT EXTENDED FROM WINK NORTHEAST TO
LUBBOCK...THEN INTO NW OKLAHOMA. SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS HAD DEVELOPED EAST OF THE FRONT IN THE PERMIAN
BASIN AND SE TEXAS PANHANDLE.
SCATTERED SHOWERS STILL EXPECTED TO MOVE INTO EASTERN SECTIONS OF
WEST CENTRAL TEXAS AFTER MIDNIGHT...AS UPPER TROUGH IN THE ROCKY
MOUNTAINS MOVES EAST. RUC MUCAPES ON SPC MESOSCALE ANALYSIS PAGE
FOR WEST CENTRAL TEXAS...WERE ON THE LOWER SIDE FOR SEVERE
STORMS...IN THE 500 TO 800 J/KG RANGE...BUT 0-6 KM SHEAR WAS
QUITE HIGH AT OVER 50 KTS. THUS WHILE A STRONG STORM OR EVEN
SEVERE STORM POSSIBLE...MOST SHOULD REMAIN BELOW SEVERE LIMITS.
MAIN POTENTIAL FOR SEVERE WEATHER TONIGHT...MAY BE DAMAGING WINDS
..IF THE STRONG WINDS ASSOCIATED WITH THE 50-60 KT LOW LEVEL JET
PARTIALLY MIX TO GROUND LEVEL WITH PRECIPITATION.
FORECAST LOOKS TO BE IN GOOD SHAPE...THUS WILL NOT MAKE CHANGES
AT THIS TIME.
PREV DISCUSSION... /ISSUED 520 PM CST SAT NOV 10 2012/
UPDATE...
SEE 00Z AVIATION DISCUSSION BELOW.
AVIATION...
VFR CONDITIONS TO PREVAIL THE MAJORITY OF THE TIME ACROSS WEST
CENTRAL TEXAS TERMINALS. STARTING TO SEE A FEW SHOWERS DEVELOP
ACROSS THE SOUTH PLAINS...AND THESE SHOULD GRADUALLY MOVE EAST AND
INCREASE IN COVERAGE SOME THROUGH THE OVERNIGHT HOURS. BETTER
CHANCES ACROSS THE BIG COUNTRY...WITH THE ABILENE...KABI...
TERMINAL THE MOST LIKELY TO SEE ONE OF THESE STORMS.
STILL...TIMING AND COVERAGE REMAINS A QUESTION...SO WILL NOT
INCLUDE ANYTHING MORE THAN A VCTS.
OTHERWISE...BREEZE SOUTH WINDS TO CONTINUE OVERNIGHT...AND WILL
LIKELY SEE A FEW STRATUS...BUT MAY ACTUALLY HAVE A HARD TIME
FORMING ANYTHING MORE THAN A BRIEF CIG. COLD FRONT MOVES QUICKLY
THROUGH ON SUNDAY...BRINGING DRIER CONDITIONS ON STRONG WEST WINDS.
PREV DISCUSSION... /ISSUED 359 PM CST SAT NOV 10 2012/
SHORT TERM...
UPPER LEVEL TROUGH MOVING ACROSS THE ROCKIES THIS AFTERNOON...WITH
MODELS SHOWING THE BEST SYNOPTIC LIFT MOVING ACROSS THE BIG COUNTRY
NORTHWARD INTO OKLAHOMA AND KANSAS LATER THIS EVENING. MAIN SURFACE
LOW WELL NORTH...BUT DRYLINE HAS TRIED TO BECOME ESTABLISHED SOUTH
THROUGH MUCH OF WEST TEXAS. ATMOSPHERE HAS BEEN CAPPED SO FAR AHEAD
OF THIS DRYLINE...BUT APPROACHING LIFT SHOULD BE ABLE TO ERODE THIS
CAP THIS EVENING. STILL LOOKS LIKE MOST OF THE CONVECTION WILL BE
FARTHER NORTH...WITH THE TAIL END ACROSS THE BIG COUNTRY AND PERHAPS
AS FAR SOUTH AS THE CONCHO VALLEY. ONCE STORMS DEVELOP...SHOULD
SOLIDIFY INTO A MORE SOLID AREA AS LOW LEVEL JET OF 50 KNOTS
DEVELOPS.
PACIFIC FRONT OVERTAKES THE DRYLINE AND PUSHES QUICKLY ACROSS WEST
CENTRAL TEXAS BETWEEN 12Z AND 18Z ON SUNDAY. WILL CONTINUE THE
CHANCE OF STORMS THROUGH THE MORNING HOURS WITH CONVECTION STILL
LIKELY ONGOING ACROSS THE AREA...WITH A MUCH DRIER AIR MASS
FOLLOWING THE FRONT FOR THE AFTERNOON. BREEZY WEST WINDS...WHICH ARE A
DOWNSLOPE...WILL OFFSET A LITTLE OF THE COLD ADVECTION...AND WILL
KEEP TEMPERATURES ON THE WARM SIDE OF GUIDANCE.
FIRE WEATHER CONCERNS WILL ALSO NEED TO BE MONITORED SUNDAY
AFTERNOON...AS HUMIDITY AND WIND CONDITIONS MAY APPROACH RED FLAG
CRITERIA. HOWEVER...RECENT RAINFALL HAS ACTUALLY ALLOWED FOR A
LITTLE BETTER VEGETATION. NEXT SHIFT WILL NEED TO MONITOR...BUT WILL
HOLD OFF ON ANY HIGHLIGHTS FOR NOW.
07
FOR THE REMAINDER OF THE SHORT TERM...THROUGH TUESDAY...LOOK FOR
UNSEASONABLY COLD TEMPERATURES. THE NAM AND GFS ARE IN VERY GOOD
AGREEMENT THIS CYCLE. OVERNIGHT TOMORROW NIGHT...TEMPERATURES AT
850 MB WILL RANGE FROM AROUND 2 CELSIUS ACROSS THE NORTHERN BIG
COUNTRY TO AROUND 5 CELSIUS AROUND OUR SOUTHERN COUNTIES.
PLUS...SURFACE WINDS TOMORROW NIGHT WILL BE VERY LIGHT TO PERHAPS
CALM...AS SURFACE HIGH PRESSURE DOMINATES TEXAS. THESE TWO
FACTORS...ALONG WITH CLEAR SKIES AND ASSOCIATED RADIATIONAL
COOLING...WILL PRODUCE LOWS SUNDAY NIGHT AROUND 30. DURING THE
DAY MONDAY...THE SURFACE HIGH WILL SLIDE EAST...AND SOUTHERLY
SURFACE RETURN FLOW WILL DEVELOP. HOWEVER...850 MB TEMPERATURES DO
NOT REBOUND MUCH DURING THE DAY. THUS...AFTERNOON HIGHS MAINLY IN
THE 55 TO 60 RANGE AND WELL BELOW SEASONAL NORMALS LOOK LIKELY.
OVERNIGHT MONDAY NIGHT...RADIATIONAL COOLING AND LIGHT WINDS WILL
AGAIN PRODUCE LOWS BELOW THE FREEZING MARK...WITH SOME AREAS
LIKELY FALLING INTO THE MID 20S HARD-FREEZE RANGE. FOR
TUESDAY...850 MB TEMPERATURES BEGIN TO REBOUND SLIGHTLY. WITH LOTS
OF SUNSHINE TUESDAY...I EXPECT AFTERNOON HIGHS VERY CLOSE TO MEX MOS
GUIDANCE NUMBERS...MAINLY IN THE 60 TO 65 RANGE.
HUBER
LONG TERM...
TEMPERATURES CONTINUE A SLOW REBOUND INTO THE START OF NEXT
WEEKEND. ALOFT...THE PATTERN SHIFTS FROM A BROAD RIDGE TO MAINLY
ZONAL FLOW. AT THE SURFACE...SOUTHERLY FLOW DOMINATES THE BOUNDARY
LAYER...AND SURFACE DEWPOINT TEMPERATURES RETURN TO THE MID TO
UPPER 50S BY FRIDAY AFTERNOON. TEMPERATURE NUMBERS CLOSE TO MEX
MOS GUIDANCE LOOK GOOD...WITH AFTERNOON HIGHS WELL ABOVE SEASONAL
NORMALS FOR SATURDAY.
HUBER
&&
.PRELIMINARY POINT TEMPS/POPS...
ABILENE 58 70 31 54 29 / 30 20 5 5 0
SAN ANGELO 59 71 31 58 29 / 20 20 5 5 0
JUNCTION 61 75 29 61 28 / 10 30 5 5 0
&&
.SJT WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
07
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
540 PM CST MON NOV 12 2012
.SHORT TERM...THROUGH THURSDAY
200 PM CST MON NOV 12 2012
MAIN FORECAST CONCERNS ARE ON TEMPERATURES AND IF ANY WEAK SHORTWAVE
TROUGHS IMPACTING THE AREA NEXT FEW DAYS CAN PRODUCE PRECIPITATION.
CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS
SHOWED WEAK RIDGING OVER THE NORTHERN U.S. ROCKIES AHEAD OF A
SHORTWAVE TROUGH IN EASTERN PORTIONS OF OREGON AND WASHINGTON...AND
PROGRESSIVE DEEP TROUGHING FROM HUDSON BAY SOUTHWARD THROUGH
WISCONSIN AND INTO MISSOURI. PLENTY OF COLD AIR UNDER THIS DEEP
TROUGHING...NOTED BY 12Z MPX SOUNDING REPORTING 925MB AND 850MB
TEMPS OF -11C AND -16C RESPECTIVELY. THE COLD AIR COMBINED WITH
PLENTY OF MOISTURE FROM 900-700MB ON THAT 12Z MPX SOUNDING IN THE
DENDRITIC GROWTH ZONE...AS WELL AS DAYTIME HEATING ADDING A LITTLE
INSTABILITY...HAS RESULTED IN PLENTY OF CLOUDS...FLURRIES AND SNOW
SHOWERS ACROSS MUCH OF THE FORECAST AREA. ONE NARROW BAND EVEN
BROUGHT THE VISIBILITY DOWN TO 1/4SM AT THE OFFICE AND KLSE AIRPORT
FOR ABOUT 10 MINUTES AROUND 18Z. SUBSIDENCE AND DRYING ON THE BACK
SIDE OF THE TROUGH...SEEN IN THE 12Z BIS SOUNDING...IS HELPING TO
CLEAR SKIES OUT ACROSS THE DAKOTAS AND SOUTHWEST MINNESOTA. AT THE
SURFACE...BREEZY CONDITIONS EXIST BETWEEN A RIDGE OF HIGH PRESSURE
OVER THE DAKOTAS AND YESTERDAYS COLD FRONT THAT IS OVER LAKE ERIE.
THE CLOUDS...COLD TEMPERATURES ALOFT AND WIND HAS HELD TEMPERATURES
DOWN IN THE 20S.
TONIGHT AND TUESDAY...MODELS PROG THE WEAK UPPER RIDGE OVER THE
NORTHERN U.S. ROCKIES TO SHIFT EAST INTO THE FORECAST AREA TUESDAY
AFTERNOON AS THE SHORTWAVE TROUGH IN ITS WAKE MOVES INTO NEBRASKA.
WITH THIS RIDGE APPROACHING AND THE DEEP TROUGHING DEPARTING...
EXPECT THE SUBSIDENCE...DRYING AND CLEARING SEEN OVER THE DAKOTAS TO
SHIFT INTO THE FORECAST AREA TONIGHT. THE SURFACE HIGH PRESSURE
RIDGE WILL ALSO ACCOMPANY THE CLEARING...ALLOWING WINDS TO DECOUPLE
AND SET UP FAVORABLE RADIATIONAL COOLING CONDITIONS. IF WE HAD A
SNOWPACK LIKE OVER THE DAKOTAS...CONCERN WOULD BE THERE FOR
TEMPERATURES FALLING AT OR BELOW ZERO. HOWEVER...THE MOSTLY BARE
GROUND SHOULD HELP TO LIMIT THE FALL. STAYED TOWARDS THE LOWER END
OF GUIDANCE...ESPECIALLY AT THE FAVORED COLD SPOTS. CIRRUS CLOUDS
SHOULD BE ON THE INCREASE TUESDAY AFTERNOON AHEAD OF THAT NEXT
SHORTWAVE TROUGH. OTHERWISE DRY AND WARMER CONDITIONS ARE EXPECTED
WITH 850MB TEMPS CLIMBING UP 0 TO -3C. GENERALLY FOLLOWED A BLEND OF
STATISTICAL GUIDANCE SINCE IT SEEMED REASONABLE.
TUESDAY NIGHT AND WEDNESDAY...MODELS HAVE TRENDED MUCH FARTHER SOUTH
WITH THE SHORTWAVE TROUGH COMING INTO NEBRASKA ON TUESDAY...WITH
MOST TAKING IT DOWN INTO ARKANSAS TUESDAY NIGHT. THERE IS ANOTHER
WEAKER SHORTWAVE SUGGESTED TO MOVE ACROSS NORTH DAKOTA AND
MINNESOTA...WHICH MODELS ARE PINGING ON PRODUCING A LITTLE LIGHT
QPF TO THE NORTH OF THE FORECAST AREA BETWEEN 06-18Z WEDNESDAY.
THIS WEAKER SHORTWAVE HAS A BROAD WARM ADVECTION ZONE TO WORK
WITH...BUT THE MOISTURE AVAILABILITY IS TERRIBLE DUE THE CURRENT
DEEP TROUGH SCOURING OUT MOISTURE. GIVEN ALL OF THE ABOVE...A DRY
FORECAST FOR THIS PERIOD REMAINS INTACT. MID AND HIGH LEVEL CLOUDS
STILL LOOK ON TAP TO MOVE THROUGH THE FORECAST AREA DURING THIS
PERIOD...CLEARING OUT IN THE AFTERNOON...ASSOCIATED BOTH WITH THAT
WEAKER SHORTWAVE AND THE BROAD WARM ADVECTION ZONE. THESE CLOUDS
SHOULD LIMIT THE TEMPERATURE FALL TO THE 20S TUESDAY NIGHT...AND
SOME LOCATIONS MAY ONLY DROP TO AROUND 30. WITH 850MB TEMPS AROUND
0C ON WEDNESDAY AND AFTERNOON SUNSHINE...HIGHS SHOULD REACH THE
MID 40S TO LOW 50S AS SUGGESTED BY MOST GUIDANCE.
WEDNESDAY NIGHT AND THURSDAY...A POTENT SHORTWAVE TROUGH IS PROGGED
TO DROP DOWN INTO SASKATCHEWAN LATE WEDNESDAY...MOVING EAST INTO
ONTARIO ON THURSDAY. 12.12Z GFS/ECMWF/CANADIAN HAVE BEEN VERY
CONSISTENT ON THIS AND WITH THE TIMING. THE WEAKER SOUTHERN
EXTENSION OF THIS SHORTWAVE LOOKS TO MOVE THROUGH THE FORECAST AREA
DURING THURSDAY AFTERNOON...WITH A VERY WEAK COLD FRONT AS ITS
SURFACE REFLECTION. SIMILAR TO THE TUESDAY NIGHTWEDNESDAY
SITUATION...THIS SHORTWAVE AND COLD FRONT IS MOISTURE STARVED. IF
THERE ARE ANY CLOUDS...THEY ARE MAINLY SOUTH OF I-90 AND OF THE
MID-LEVEL VARIETY...ASSOCIATED WITH THAT BROAD WARM ADVECTION ZONE
REFERENCED IN THE TUESDAY NIGHTWEDNESDAY DISCUSSION. THUS...DRY
CONDITIONS CONTINUE. PRESSURE GRADIENT IS WEAK WEDNESDAY NIGHT SO
CONCERN EXISTS ABOUT TEMPERATURES TANKING...PARTICULARLY NORTH OF
I-90 WHERE LESS CLOUDS EXIST. 30 DAY BIAS CORRECTED GUIDANCE DOES
SHOW THE TYPICAL WISCONSIN COLD SPOTS DROPPING INTO THE LOW 20S...SO
HAVE TRENDED TOWARDS THIS. READINGS FROM THE UPPER 20S TO AT MOST
MID 30S SHOULD BE THE RULE ELSEWHERE. COMBINATION OF SUN AND 850MB
TEMPS HOLDING UP IN THE 0-2C RANGE ON THURSDAY WILL ALLOW
TEMPERATURES TO CLIMB BACK INTO THE MID 40S TO LOW 50S AGAIN. 12.12Z
NAM 2 METER TEMPERATURE OUTPUT IS EVEN HIGHER...MID TO UPPER 50S
ALONG AND WEST OF THE MISSISSIPPI RIVER...BUT IT MIGHT BE MIXING TOO
DEEPLY GIVEN SOME CLOUD CONCERNS. CERTAINLY SOMETHING TO WATCH.
.LONG TERM...THURSDAY NIGHT THROUGH MONDAY
200 PM CST MON NOV 12 2012
THE LONG TERM FORECAST CONTINUES TO REMAIN QUIET. 12.12Z
ECMWF/CANADIAN/GFS AND GFS ENSEMBLES ARE STILL PAINTING A SIMILAR
PICTURE...SHOWING A SPLIT FLOW PATTERN WITH THE NORTHERN STREAM
STAYING IN CANADA AND THE SOUTHERN STREAM CROSSING THE SOUTHERN
U.S.. IN ADDITION...DEEP TROUGHING IS PROGGED TO DEVELOP OVER THE
EAST PACIFIC...PERHAPS SLIDING INTO THE PACIFIC NORTHWEST ON MONDAY.
THIS TROUGH ONLY HELPS TO LIFT THE NORTHERN STREAM FARTHER NORTH
THROUGH CANADA AND MAY EVEN TRY TO BUILD A SOUTHERN STREAM RIDGE
INTO THE FORECAST AREA. THIS PATTERN KEEPS A FLOW OF PACIFIC AIR
INTO THE FORECAST AREA WHICH SHOULD RESULT IN SLIGHTLY ABOVE NORMAL
TEMPERATURES. 850MB TEMPS OF 0-2C ON FRIDAY LOOK TO CLIMB TO 2-4C
FOR THE WEEKEND AND AROUND 4C BY LATE MONDAY. WITH MOISTURE
EXTREMELY LIMITED ACROSS THE NORTHERN PLAINS AND UPPER MISSISSIPPI
RIVER VALLEY REGIONS...ALONG WITH A GENERAL LACK OF FORCING...HAVE
KEPT THE FORECAST DRY. MUCH OF THE TIME PERIOD IS ALSO DOMINATED BY
HIGH PRESSURE AT THE SURFACE...HELPING TO MAINTAIN A FEED OF LOW
LEVEL DRY AIR INTO THE AREA.
FOR THOSE LOOKING TOWARDS THANKSGIVING NEXT WEEK...IT APPEARS THE
DEEP EAST PACIFIC TROUGH WILL LIFT OUT ACCORDING TO THE 12.12Z
ECMWF/GFS AND LATEST CFS RUNS...RESULTING IN A ZONAL FLOW NEAR THE
U.S./CANADIAN BORDER. IF THIS DOES INDEED PAN OUT...EVEN WARMER
AIR SHOULD ADVECT INTO THE AREA. MAINLY DRY WEATHER PERSISTS TOO.
OF COURSE STAY TUNED TO LATER FORECASTS GIVEN THAT THANKSGIVING IS
STILL 9-10 DAYS OUT.
&&
.AVIATION...TONIGHT AND TUESDAY
532 PM CST MON NOV 12 2012
A TROUGH OF LOW PRESSURE WILL PRODUCE 3-4K FOOT CLOUDS THROUGH
14.03Z...AND THEN THE CLOUDS WILL QUICKLY MOVE EAST OF THE AREA.
IN ADDITION...THERE WILL BE SCATTERED SNOW SHOWERS. THESE SNOW
SHOWERS MAY BRIEFLY LOWER VISIBILITIES TO A MILE.
IN THE WAKE OF THIS SYSTEM...WEAK RIDGING WILL BUILD ACROSS THE
AREA OVERNIGHT. WEST WINDS AROUND 10 KNOTS WILL PERSIST THROUGH
MUCH TONIGHT...AND THEN SHIFT AND SOUTH AND LIGHTEN TO 5 TO 10
KNOTS.
ON TUESDAY AFTERNOON...THE CLOUDS WILL ONCE AGAIN INCREASE AS YET
ANOTHER TROUGH APPROACHES THE AREA FROM THE NORTHERN PLAINS.
CEILINGS THROUGHOUT THE AFTERNOON WILL BE MAINLY ABOVE 15K FEET.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
200 PM CST MON NOV 12 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
201 PM CST SUN NOV 11 2012
.SHORT TERM...THROUGH WEDNESDAY
201 PM CST SUN NOV 11 2012
MAIN FORECAST CONCERN IS ON TEMPERATURES THE NEXT FEW DAYS DUE TO
THE SHARPLY COLDER AIR THAT HAS BEEN ADVECTING IN TODAY.
CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT
ANALYSIS SHOWED RIDGING BUILDING UP ALONG THE WEST COAST OF THE
U.S....DEEP TROUGHING FROM MANITOBA SOUTHWESTWARD INTO THE TEXAS
PANHANDLE...AND STRONG RIDGING ALONG THE EAST COAST OF THE U.S..
WITHIN THE SOUTHWEST FLOW AHEAD OF THE DEEP TROUGH...A 120KT JET
STREAK WAS PRESENT NEAR 250MB OVER EASTERN MINNESOTA. THE
COMBINATION OF UPPER DIVERGENCE IN THE RIGHT ENTRANCE REGION OF
THIS JET...VARIOUS SHORTWAVES RIDING THROUGH THE SOUTHWEST
FLOW...A STRONG LOW TO MID-LEVEL FRONTOGENESIS ZONE NOTED IN RAP
ANALYSES AND IN 925MB AND 850MB VWP AND PROFILER DATA...AND
PLENTIFUL MOISTURE INDICATED FROM GOES DERIVED PRECIPITABLE WATER
DATA SHOWING AROUND 1 INCH IS AIDING IN WIDESPREAD PRECIPITATION.
REGIONAL RADAR IMAGERY SHOWED THE PRECIPITATION FROM EASTERN IOWA
THROUGH MUCH OF WISCONSIN AND A SMALL PORTION OF SOUTHEAST
MINNESOTA. MUCH OF THE PRECIPITATION IS FALLING AS RAIN...THOUGH
THE WESTERN EDGE HAS MIXED WITH SLEET AND SNOW DUE TO
DRAMATICALLY COLDER AIR FLOWING IN ON NORTHWEST WINDS. SURFACE
TEMPERATURES ARE MOSTLY IN THE TEENS AND 20S IN THE DAKOTAS INTO
WESTERN MINNESOTA. MEANWHILE...AHEAD OF THE SURFACE COLD FRONT
INDICATED JUST EAST OF THE FORECAST AREA...READINGS ARE IN THE LOW
TO MID 60S FROM GREEN BAY TO MADISON. 12Z RAOBS REFLECTED THE
SHARP TEMPERATURE GRADIENT TOO...WITH 850MB READINGS OF 11C AT
GRB...3C AT MPX...-12C AT ABR AND -15C AT BIS. LAST ITEM OF NOTE
IS SKIES THAT HAVE CLEARED OUT OVER EASTERN SOUTH DAKOTA INTO
SOUTHWEST MINNESOTA.
TONIGHT AND MONDAY...THE DEEP UPPER TROUGH OVER THE PLAINS IS
PROGGED TO PROGRESS EASTWARD THROUGH THIS PERIOD...WITH ITS AXIS
SITTING OVER THE AREA MONDAY MORNING...THEN SHIFTING INTO THE GREAT
LAKES MONDAY AFTERNOON. WITH THIS UPPER TROUGH WILL COME THE COLDER
AIR WITH 850MB AND 925MB TEMPS FORECAST TO TANK BY 12Z TO -12 TO
-16C AND -8 TO -11C RESPECTIVELY. THESE ARE 2 STANDARD DEVIATIONS
BELOW NORMAL. THUS...EXPECT A MUCH COLDER NIGHT TONIGHT AND DAY ON
MONDAY. THE TEMPERATURES WILL STILL BE OFF THE COLDEST HIGH
TEMPERATURE FOR A DAY AT LA CROSSE AND ROCHESTER OF 14 AND 11
RESPECTIVELY...SET AFTER THE ARMISTICE DAY STORM OF 1940. WITH THE
EASTWARD PROGRESSION OF THE UPPER TROUGH...ANTICIPATING
PRECIPITATION TO END WEST TO EAST THIS EVENING. A LITTLE SNOW IS
POSSIBLE...BUT THE WARM GROUND SHOULD LIMIT ACCUMULATIONS TO A HALF
INCH OR LESS...MOSTLY ON GRASSY SURFACES. SKIES WILL CLEAR FOR
MOST LOCATIONS TONIGHT AS THE DRIER AIR IN SOUTH DAKOTA AND
SOUTHWEST MINNESOTA PUSHES IN. HOWEVER...A SURFACE TROUGH
ACCOMPANYING THE CORE OF THE COLD AIR IS SLATED TO CROSS THE AREA ON
MONDAY...BRINGING WITH IT A RAPID INCREASE OF CLOUDS. IN
ADDITION...THE COMBINATION OF DIURNAL HEATING AND THE CLOUDS BEING
SITUATED IN THE DENDRITIC GROWTH ZONE WILL LIKELY LEAD TO
FLURRY/SNOW SHOWER DEVELOPMENT. BEST CHANCE OF SEEING SOME LIGHT
SNOW SHOWER ACCUMULATION WILL BE NORTH OF I-90 WHERE DEEPER MOISTURE
EXISTS.
MONDAY NIGHT AND TUESDAY...THE UPPER RIDGE THAT IS BUILDING ALONG
THE WEST COAST OF THE U.S. CURRENTLY LOOKS TO FLATTEN OUT AND PUSH
EAST INTO THE FORECAST AREA BY TUESDAY. THIS IN RESPONSE TO NUMEROUS
SHORTWAVES COMING OFF THE EAST PACIFIC. ACCOMPANYING THE FLATTENING
UPPER RIDGE WILL BE A SURFACE HIGH PRESSURE RIDGE AS WELL AS WARMER
925-850MB AIR. BY 00Z WEDNESDAY...850MB TEMPS SHOULD HAVE CLIMBED TO
0 TO -3C PER MODEL CONSENSUS...MUCH WARMER THAN THOSE SEEN ON
MONDAY. THEREFORE...AFTER WHAT WILL LIKELY BE A CHILLY NIGHT MONDAY
NIGHT DUE TO THE COLD START...WINDS DROPPING OFF TO CALM WITH THE
SURFACE RIDGE AND SKIES CLEARING OUT...TEMPERATURES SHOULD REBOUND
INTO THE MID 30S TO PERHAPS EVEN LOWER 40S. WARMEST READINGS WOULD
OCCUR ALONG/WEST OF THE MISSISSIPPI RIVER DUE TO THE WARMER AIR
COMING IN THERE FIRST. DROPPED LOWS 5 TO 10 DEGREES MONDAY NIGHT
FROM THE PREVIOUS FORECAST DUE TO THE FAVORABLE RADIATIONAL
COOLING CONDITIONS EXPECTED. THE FORECAST LOW TEMPERATURES LEAN
CLOSELY TOWARDS THE MET GUIDANCE. SOME INCREASE IN CLOUDS OCCURS
LATE ON TUESDAY WITH THE WARMER AIR MOVING IN...ALONG WITH A
SHORTWAVE TROUGH ENTERING THE NORTHERN PLAINS...BUT THESE SHOULD
NOT HAMPER MIXING OR PRODUCE ANY PRECIPITATION DUE TO LOW LEVEL
DRY AIR PRESENT.
TUESDAY NIGHT AND WEDNESDAY...MODELS PROG THE SHORTWAVE TROUGH IN
THE NORTHERN PLAINS LATE TUESDAY TO MOVE NORTHEAST AND ACROSS THE
AREA WEDNESDAY MORNING. PRECIPITABLE WATER VALUES SUGGEST SOMEWHAT
LIMITED MOISTURE WITH THE TROUGH...ANYWHERE FROM 0.3-0.5 INCHES...
HIGHEST JUST NORTH OF THE FORECAST AREA. ISENTROPIC LIFT PROGS ON
THE 280-290K SURFACES COMBINED WITH CONDENSATION PRESSURE DEFICITS
FORECAST BEST JUXTAPOSITION IS JUST NORTH OF THE FORECAST AREA.
THUS...THINKING ANY PRECIPITATION POTENTIAL WILL ALSO STAY JUST
NORTH OF THE FORECAST AREA...SIMILAR TO WHAT DERIVED QPF OUTPUT
SHOWS FROM THE 11.12Z NAM/GFS/ECMWF AND 11.15Z SREF MEAN.
THEREFORE...HAVE STAYED WITH A DRY FORECAST. ALTHOUGH NO
PRECIPITATION IS ANTICIPATED...AN INCREASE OF CLOUDS WILL OCCUR FOR
TUESDAY NIGHT INTO WEDNESDAY MORNING...BEFORE SUBSIDENCE IN THE WAKE
OF THE SHORTWAVE TROUGH HELPS CLEAR THEM OUT WEDNESDAY AFTERNOON.
WITH MORE CLOUDS TUESDAY NIGHT...MUCH WARMER TEMPERATURES ARE
EXPECTED COMPARED TO MONDAY NIGHT. STAYED WITH A BLEND OF GUIDANCE
FOR LOWS. 850MB TEMPS HOVERING NEAR 0C ON WEDNESDAY AND THE
AFTERNOON SUN SHOULD ALLOW TEMPERATURES TO CLIMB UP INTO THE LOW TO
MID 40S IN MOST LOCATIONS.
.LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY
201 PM CST SUN NOV 11 2012
THE LONG TERM FORECAST LOOKS GENERALLY QUIET WEATHER WITH
TEMPERATURES NEAR TO SLIGHTLY ABOVE NORMAL. UPPER LEVEL PATTERN
SUGGESTED BY THE 11.12Z ECMWF/GFS/CANADIAN AND GFS
ENSEMBLES...ALONG WITH THEIR PREVIOUS RUNS...FEATURES A SPLIT
FLOW PATTERN...WITH THE NORTHERN STREAM MOSTLY TRACKING ACROSS
SOUTHERN CANADA AND THE SOUTHERN STREAM GOING ACROSS THE SOUTHERN
U.S.. THERE IS SOME AMPLIFICATION THAT TAKES PLACE TO THE NORTHERN
STREAM FOR THE END OF THE WEEKEND IN RESPONSE TO A DEEP TROUGH
FORMING OVER THE EAST PACIFIC...HELPING TO KEEP A PACIFIC FLOW OF
AIR ACROSS THE CONUS. THERE ARE A FEW HIGHLIGHTS IN THE EXTENDED.
FIRST...A SHORTWAVE TROUGH IS INDICATED BY ALL MODELS TO CROSS THE
AREA ON THURSDAY WITH A WEAK COLD FRONT ACCOMPANYING IT. BEST
FORCING WITH THIS TROUGH LOOKS TO OCCUR NORTH OF THE FORECAST
AREA...AND IN CONJUNCTION WITH LIMITED MOISTURE...HAVE KEPT THE
FORECAST DRY. THE NEXT HIGHLIGHT IS A SHORTWAVE ALONG THE
SUBTROPICAL JET WHICH MODELS HAVE BEEN ADVERTISING MOVING INTO THE
CENTRAL PLAINS SATURDAY NIGHT...THEN SLOWLY PROGRESSING EASTWARD
ON SUNDAY. IT APPEARS ANY FORCING AND PRECIPITATION FROM THIS
SHORTWAVE WILL STAY TO THE SOUTHWEST...THUS HAVE KEPT SATURDAY
NIGHT THROUGH SUNDAY DRY.
&&
.AVIATION...THROUGH 18Z MONDAY
1147 AM CST SUN NOV 11 2012
A STRONG COLD FRONT WILL MOVE QUICKLY EAST THROUGH CENTRAL
AND SOUTHWEST WISCONSIN. THIS FRONT HAS ALREADY CLEARED BOTH TAF
SITES. FOR THIS AFTERNOON...NORTHWEST WINDS WILL BE SUSTAINED IN
THE 10 TO 20 KNOT RANGE AND THE WINDS WILL OCCASIONALLY GUST UP TO
25 KNOTS. STRONG FRONTOGENESIS ON THE BACK SIDE OF THIS FRONT WILL
KEEP PRECIPITATION AT KLSE THROUGH 11.04Z. SOUNDINGS SUGGEST THAT
THE RAIN WILL CHANGE OVER TO SLEET AND SNOW AROUND 11.22Z...AND
TO SNOW BY 12.00Z. UP TO A HALF INCH OF SNOW ACCUMULATION WILL BE
POSSIBLE MAINLY ON GRASSY SURFACES. CEILINGS WILL BE PRIMARILY
IFR AND VISIBILITIES MVFR. MEANWHILE AT KRST...THEY ARE ON THE
WESTERN EDGE OF THIS PRECIPITATION BAND. EXPECTING THE RAIN TO
CHANGE OVER TO A MIX OF SLEET AND SNOW BY 11.19Z...AND TO SNOW BY
11.21Z. NOT EXPECTING ANY ACCUMULATION OF SNOW. VISIBILITIES WILL
BE MAINLY VFR AND OCCASIONALLY DROP TO MVFR. CEILINGS WILL START
OUT AS IFR AND THEN RAISE TO MVFR BY LATE AFTERNOON.
FOR TONIGHT...EXPECT SKIES TO CLEAR AT KRST AROUND 12.02Z AND AT
KLSE AROUND 12.06Z.
ON MONDAY MORNING...A SHORT WAVE TROUGH WILL MOVE INTO THE REGION.
AS IT APPROACHES A MVFR DECK WILL MOVE INTO KRST AROUND 12.11Z AND
KLSE AROUND 12.12Z.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
201 PM CST SUN NOV 11 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...BOYNE
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1150 AM CST SUN NOV 11 2012
.SHORT TERM...TODAY
607 AM CST SUN NOV 11 2012
BASED ON THE LAST FEW RUNS OF RAP SOUNDINGS ACROSS THE
REGION...HAVE DECIDED TO PULL THE FREEZING RAIN FROM THE FORECAST
FOR TODAY SINCE IT APPEARS THAT SURFACE TEMPERATURES WILL HAVE A
HARD TIME TO DROP BELOW FREEZING BEFORE THE WARM LAYER COOLS. THIS
MEANS THAT THE RAIN WILL CHANGE OVER TO A PERIOD OF SLEET/SNOW
PELLETS BEFORE CHANGING OVER TO ALL SNOW THIS AFTERNOON/EVENING.
WILL HAVE TO MONITOR THE BACK SIDE OF THE PRECIPITATION SHIELD IN
CASE ICE CREATION IS LOST IN THE -10C TO -20C DENDRITIC GROWTH
ZONE AND SOME DRIZZLE FALLS IN SUB FREEZING AIR.
.LONG TERM...WEDNESDAY THROUGH SATURDAY
313 AM CST SUN NOV 11 2012
HIGH PRESSURE SETS UP ACROSS THE EASTERN HALF OF THE US ON
WEDNESDAY AND LINGERS THROUGH NEXT WEEKEND AND SHOULD LEAVE DRY
CONDITIONS THROUGH THE PERIOD. WITH THE UPPER MISSISSIPPI RIVER
VALLEY BEING ON THE WESTERN PERIPHERY OF THE RIDGE THERE SHOULD BE
SOUTHERLY SURFACE TO LOW LEVEL WINDS THAT WILL KEEP TEMPERATURES
AT ABOUT NORMAL.
&&
.AVIATION...THROUGH 18Z MONDAY
1147 AM CST SUN NOV 11 2012
A STRONG COLD FRONT WILL MOVE QUICKLY EAST THROUGH CENTRAL
AND SOUTHWEST WISCONSIN. THIS FRONT HAS ALREADY CLEARED BOTH TAF
SITES. FOR THIS AFTERNOON...NORTHWEST WINDS WILL BE SUSTAINED IN
THE 10 TO 20 KNOT RANGE AND THE WINDS WILL OCCASIONALLY GUST UP TO
25 KNOTS. STRONG FRONTOGENESIS ON THE BACK SIDE OF THIS FRONT WILL
KEEP PRECIPITATION AT KLSE THROUGH 11.04Z. SOUNDINGS SUGGEST THAT
THE RAIN WILL CHANGE OVER TO SLEET AND SNOW AROUND 11.22Z...AND
TO SNOW BY 12.00Z. UP TO A HALF INCH OF SNOW ACCUMULATION WILL BE
POSSIBLE MAINLY ON GRASSY SURFACES. CEILINGS WILL BE PRIMARILY
IFR AND VISIBILITIES MVFR. MEANWHILE AT KRST...THEY ARE ON THE
WESTERN EDGE OF THIS PRECIPITATION BAND. EXPECTING THE RAIN TO
CHANGE OVER TO A MIX OF SLEET AND SNOW BY 11.19Z...AND TO SNOW BY
11.21Z. NOT EXPECTING ANY ACCUMULATION OF SNOW. VISIBILITIES WILL
BE MAINLY VFR AND OCCASIONALLY DROP TO MVFR. CEILINGS WILL START
OUT AS IFR AND THEN RAISE TO MVFR BY LATE AFTERNOON.
FOR TONIGHT...EXPECT SKIES TO CLEAR AT KRST AROUND 12.02Z AND AT
KLSE AROUND 12.06Z.
ON MONDAY MORNING...A SHORT WAVE TROUGH WILL MOVE INTO THE REGION.
AS IT APPROACHES A MVFR DECK WILL MOVE INTO KRST AROUND 12.11Z AND
KLSE AROUND 12.12Z.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
313 AM CST SUN NOV 11 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...BOYNE
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1119 AM CST SUN NOV 11 2012
.UPDATE...INTERESTING DAY AHEAD AS A STRONG COLD FRONT APPROACHES
FROM THE WEST AHEAD OF A DEEP UPPER-LEVEL TROUGH AS SEEN IN THE
MID- AND UPPER-LEVEL MODEL ANALYSES. MAIN CONCERNS TODAY WILL BE
TIMING OF THE SURFACE COLD FRONT...AND ITS ASSOCIATED IMPACT ON
TEMPS AND WINDS...AND WEATHER/POPS. NO CHANGES IN HEADLINES IN
THIS UPDATE. WIND ADVISORY IN EFFECT FOR SOUTHEAST AND PORTIONS
SOUTH CENTRAL TODAY ENDING AT 6PM...WITH FAR EAST COUNTIES ENDING
AT 8PM.
MSAS AND SFC OBS AS OF 9 AM SHOW SURFACE COLD FRONT POSITION ALONG
A LINE FROM JUST EAST OF EAU CLAIRE WI...TO NEAR DECORAH IA...TO
NEAR OTTUMWA IA. QUITE A TEMPERATURE GRADIENT...WITH TEMPERATURES
FALLING SHARPLY BEHIND FROPA. AT 9AM...LA CROSSE WAS 57 AHEAD OF
FROPA WITH PRESTON AT 41 BEHIND IT...TO 30 AT FAIRBAULT MN. VIS
SAT SHOWS A DENSE CLOUD SHIELD THAT IS INTO PORTIONS OF SE WI AND
GOES BACK TO EASTERN MN.
NOT MANY CHANGES MADE TO TEMPERATURE AND WIND FCST SO FAR IN THE
TODAY PERIOD. THOUGH UPDATED THE IMMEDIATE NEAR-TERM FOR
TRENDS...WITH TEMPS AND WINDS ON TRACK WITH GUIDANCE AND THE
EXPECTED FROPA STILL. WX/POPS WERE TRIMMED BACK IN THE NEAR-TIME
WITH RESPECT TO TIMING BASED ON RADAR AND HI-RES MODEL. WINDS WILL
HAVE TO BE WATCHED...AS NAM SOUNDINGS WITH GOOD LOW LEVEL
TEMPERATURE PROFILE SHOWED BORDERLINE CRITERIA BEING MET FOR GUSTS
AND SUSTAINED WINDS.
ELSEWHERE...POPS AND WX LATER IN THE AFTERNOON AND EVENING WERE
NOT CHANGED MUCH. WILL MONITOR THIS CLOSELY AS WELL. THE HI-RES
MODELS...LOCAL WRF AND HRRR...REFLECTIVITY FIELDS ARE HANDLING THE
NATURE AND TIMING OF THE PRESENT PRECIPITATION WELL COMPARED TO
THE RADAR MOSAIC...WILL BE USING THEM FOR POPS/WX TIMING IN
CONJUNCTION WITH RADAR. GIVEN ELEVATED CAPE...ISOLATED THUNDER
POSSIBLE TODAY...ESPECIALLY WITH THE LIFT AVAILABLE.
PRECIPITATION FIELD CORRESPONDS WELL WITH STRONG SURFACE
FRONTOGENESIS AND THE FIELDS LOCATION WITH RESPECT TO STRONG
LLJ/LLJ NOSE. AT NOON AT 850 HPA...A WIND MAX OF AROUND 60-65 KTS
IS SEEN GENERALLY SOUTH OF WI-IL BORDER...WITH LLJ STRENGTHENING
AND POSITIONING ITSELF OVER LAKE MICHIGAN THIS AFTERNOON. THE
DETERMINISTIC MODELS ARE GENERALLY SIMILAR IN POSITION AND SPEEDS
OF LLJ...THOUGH THE GFS AND RAP ARE A BIT STRONGER. DO EXPECT COLD
FRONT TO SPEED UP A BIT IN THE AFTERNOON...AS SFC LOW LIFTS AND
MOVES TO THE NE TOWARDS JAMES BAY.
&&
.AVIATION/18Z TAFS/...RAIN WITH MVFR/IFR CEILINGS AND VISIBILITIES
SHOULD REACH MADISON BY 20Z SUNDAY...AND THE EASTERN TAF SITES
BETWEEN 22Z SUNDAY AND 00Z MONDAY. ISOLATED THUNDERSTORMS ARE
EXPECTED ALONG THE LEADING EDGE OF THE STRONG COLD FRONT. THE
FRONT WILL REACH MADISON BY 23Z SUNDAY...AND THE EASTERN SITES
BETWEEN 01Z AND 03Z MONDAY. GUSTY SOUTH WINDS AHEAD OF THE FRONT
MAY GUST TO 39 KNOTS. WINDS WILL SLOWLY WEAKEN AND SHIFT WEST
BEHIND THE FRONT..WITH GUSTS TO 20 KNOTS STILL EXPECTED.
THE RAIN WITH MVFR/IFR CONDITIONS WILL LINGER THIS EVENING...THEN
END AT MADISON BY 06Z MONDAY...AND THE EASTERN SITES BY 10Z TO 11Z
MONDAY. MAY SEE LIGHT SNOW SHOWERS MIX IN BRIEFLY WITH THE RAIN
TOWARDS THESE ENDING TIMES...BUT NOT CONFIDENT ENOUGH TO MENTION
IN TAFS AT THIS TIME.
BRISK WEST WINDS WILL LINGER THROUGH MONDAY...GUSTING TO 25 KNOTS
AT TIMES. MVFR/IFR CEILINGS AND VISIBILITIES WILL IMPROVE TO VFR
AFTER THE PRECIPITATION ENDS...WITH SCATTERED TO BROKEN CUMULUS
AND FLURRIES EXPECTED BY MONDAY AFTERNOON.
&&
.MARINE...GALE WARNING CONTINUES UNTIL 03Z MONDAY ACROSS THE
NEARSHORE WATERS. TIGHT PRESSURE GRADIENT AND STRONG MIXING OF
WINDS FROM THE LOW LEVELS SHOULD BRING FREQUENT GUSTS TO 40 KNOTS
DURING THIS TIME. HIGH WAVES WILL RESULT...UP TO 4 TO 8 FEET.
THE STRONG COLD FRONT WILL MOVE THROUGH THIS AREA EARLY THIS
EVENING...WHICH WILL BRING SLIGHTLY WEAKER WINDS THAT WILL SHIFT
WEST AFTER THE FRONTAL PASSAGE. THESE WINDS WILL REMAIN GUSTY UP
TO 25 KNOTS TONIGHT AND MONDAY...LINGERING INTO MONDAY EVENING.
THESE WINDS WILL HELP WAVES SUBSIDE QUICKLY THIS EVENING...AND
REMAINING BELOW 4 FEET THROUGH MONDAY NIGHT.
THUS...A SMALL CRAFT ADVISORY WILL BE NEEDED AFTER THE GALE
WARNING EXPIRES AND THROUGH MONDAY/MONDAY EVENING.
&&
.PREV DISCUSSION... /ISSUED 343 AM CST SUN NOV 11 2012/
SHORT TERM...
TODAY-FORECAST CONFIDENCE HIGH
STRONG DYNAMIC SETUP COMING UP TODAY. DEEP UPPER TROUGH IN THE
ROCKIES PUSHES OUT INTO THE PLAINS WITH STRONG HEIGHT FALLS THIS
AFTERNOON. 500 MB 12 HOUR FALLS OF 60 TO 80 METERS SPREAD INTO
SOUTHERN WISCONSIN DURING THE AFTERNOON AS SURFACE COLD FRONT
APPROACHES.
ALTHOUGH SURFACE LOW NOT EXPECTED TO DEEPEN AS IT LIFTS INTO
NORTHWEST ONTARIO...VERY STRONG AND DEEP FRONTOGENESIS SHOWN BEHIND
SURGING COLD FRONT. THIS FRONT SHOULD ENTER FAR WEST AROUND NOON
AND THEN PROBABLY JUST EAST OF A LINE FROM FLD TO RFD BY 00Z MON.
BRIEF PERIOD OF NEAR WIND ADVISORY CONDITIONS ALREADY OCCURRED WITH
EARLIER 65 KNOT 850 MB WIND MAX THAT PUSHED THROUGH. MODELS SHOW A
LULL IN LOW LEVEL JET THEN A NEW NARROW SURGED SHOWN JUST AHEAD OF
THE FRONT LATER THIS MORNING INTO THIS AFTERNOON. GFS SHOWS UP TO
80 KNOTS AT 850 MB OVER SHEBOYGAN BY LATE AFTERNOON. WITH MEAN WIND
IN SURFACE TO 850 MB LAYER OF NEARLY 60 KNOTS...CERTAINLY CONCERN
FOR STRONG WIND GUSTS SO WILL GO WITH WIND ADVISORY FOR THE CENTRAL
AND EASTERN PORTIONS OF THE CWA. HRRR SURFACE GUST POTENTIAL
INDICATES 40 KNOTS AND GFS BUFKIT SHOWING SIMILAR GUST POTENTIAL
ESPECIALLY TOWARD THE LAKE SHORE.
RAIN SHOULD SPREAD EAST ALONG WITH A FEW RUMBLES OF THUNDER AND MAY
NOT QUITE REACH LAKE SHORE BY 00Z.
TONIGHT-FORECAST CONFIDENCE HIGH
CONTINUED CRASHING OF UPPER HEIGHTS AS FULL LATITUDE TROUGH CRASHES
THROUGH THE MISSISSIPPI RIVER VALLEY. 500 MB 12 HOUR FALLS OF 180
METERS SPREAD ACROSS SOUTHERN WISCONSIN...HELPING USHER IN MUCH
COLDER AIR.
WINDS SHOULD DIE DOWN BEHIND COLD FRONT SO WILL LET WIND ADVISORY
EXPIRE IN THE WESTERN AREAS AT 00Z AND 02Z IN THE EAST PER
COORDINATION WITH DVN AND LOT WFOS.
RAIN SHOULD END PRIOR TO AIR COOLING ENOUGH FOR CHANGE OVER TO
SNOW. HOWEVER...HAVE A CHANCE OF LIGHT SNOW AT THE TAIL END OF THE
PRECIPITATION BUT GUT FEELING IS THAT PROBABLY IS PRETTY LOW.
ALMOST ALL OF THE GUIDANCE SHOWS THE PRECIP CUTTING OFF RIGHT ABOUT
THE TIME THAT THE 850 MB TEMPERATURE CRASHES TO ZERO OR COLDER.
TREMENDOUS COLD ADVECTION SHOULD DROP WESTERN AREAS INTO THE LOWER
20S BY MORNING DESPITE CLOUD COVER WITH CONSENSUS 850 MB TEMPS DOWN
TO -10C BY 12Z MONDAY.
MONDAY THROUGH MONDAY NIGHT...FORECAST CONFIDENCE MEDIUM.
IT WILL BE A COLD...DRY AND MOSTLY CLOUDY MONDAY. EXPECT CLEARING
BEHIND THE FRONT TO LAST INTO MONDAY MORNING AND THEN INSTABILITY
CLOUDS WITH THE STEEP LOW LEVEL LAPSE RATES IN THE CYCLONIC FLOW
REGIME WILL QUICKLY DEVELOP LATE IN THE MORNING. FLURRIES ARE
POSSIBLE WITH THE AFTERNOON LOW CLOUDS. WINDS WILL BE BRISK OUT OF
THE WEST 15 TO 20 MPH WITH HIGHER GUSTS. MAX TEMPS WILL WILL BE IN
THE LOWER 30S...WITH A FEW LOCATIONS EXPECTED TO STAY BELOW FREEZING.
LINGERING TIGHT PRESSURE GRADIENT ABOVE THE SURFACE WILL ONLY ALLOW
FOR A WEAK INVERSION...THUS KEEPING MIN TEMPS IN CHECK. WITH 925MB
TEMPS AROUND -4C...EXPECT LOWS IN THE LOWER 20S. A FEW LOCATIONS MAY
SEE LOWS IN THE TEENS.
TUESDAY THROUGH THURSDAY...FORECAST CONFIDENCE IS MEDIUM TO HIGH.
HIGH PRESSURE WILL RETURN AND BRING DRY WEATHER FOR MUCH OF THE
REMAINDER OF THIS WEEK. 500MB PATTERN WILL BECOME ZONAL OVER THE
NORTHERN PLAINS AND UPPER GREAT LAKES. A SMALL RIPPLE IN THE FLOW
MAY BRING LIGHT RAIN TO WI TUE NIGHT/WED...BUT IT LOOKS LIKE IT JUST
MIGHT BE INCREASING CLOUDS WITH ISENTROPIC LIFT/WARM AIR ADVECTION.
THE LOW LEVELS ARE EXPECTED TO BE TOO DRY TOO ALLOW FOR ANY
MEASURABLE PRECIP. DRY FORECAST FOR SOUTHERN WI CONTINUES.
TEMPS WILL GRADUALLY WARM THROUGH THE WEEK...BEGINNING AROUND 40 ON
TUESDAY AND ENDING UP AROUND 50 FOR THE WEEKEND.
LONG TERM...
NEXT WEEKEND...FORECAST CONFIDENCE MEDIUM.
MODELS TRENDED AWAY FROM PRECIP CHANCES IN SOUTHERN WISCONSIN OVER
THE WEEKEND. IT LOOKS LIKE BLOCKING HIGH PRESSURE WILL BE IN CONTROL
WITH DRY WEATHER THROUGH EARLY NEXT WEEK. MAX TEMPS WILL BE AROUND
50.
AVIATION/12Z TAFS/...
LOW LEVEL SHEAR EARLY THIS MORNING WITH 55 KNOTS AT 2000 FEET AGL
SHOULD RELAX AS SURFACE WINDS INCREASE.
GUSTY SOUTH WINDS TO 35 OR 40 KNOTS EXPECTED ESPECIALLY AT KMKE AND
KENW THIS AFTERNOON AND EARLY EVENING AHEAD OF STRONG COLD FRONT.
PERIOD OF IFR CEILINGS AND VISIBILITIES IN MODERATE TO BRIEFLY HEAVY
RAIN AND RUMBLE OF THUNDER EXPECTED JUST BEHIND COLD FRONT THIS
AFTERNOON IN KMSN AND IN SOUTHEAST TAF SITES LATE AFTERNOON AND
EVENING.
WINDS SHIFT TO WEST AND DIMINISH RAPIDLY BEHIND COLD FRONT THIS
EVENING. CEILINGS SHOULD IMPROVE TO MVFR AFTER RAIN ENDS DURING THE
EVENING AND THEN EVENTUALLY TO VFR AFTER MIDNIGHT AS COLDER AND
DRIER AIR MOVES IN.
NOT IMPOSSIBLE FOR RAIN TO END AS BRIEF PERIOD OF WET SNOW OR SLEET
AT KMSN DURING THE EVENING...BUT NOT MUCH IMPACT EXPECTED WITH
SLIGHTLY ABOVE FREEZING TEMPERATURES.
MARINE...
ALREADY GUSTING NEAR GALE FORCE EARLY THIS MORNING AT KENOSHA HARBOR
AND EXPECT GALE FORCE SOUTHERLY GUSTS LATER THIS MORNING AND THIS
AFTERNOON AHEAD OF STRONG COLD FRONT. THUS GALE WARNING FOR MID
MORNING INTO THE EVENING LOOKS GOOD.
WINDS SHIFT TO WEST AND DIMINISH RAPIDLY AFTER COLD FRONTAL PASSAGE
THIS EVENING. DUE TO HIGH WAVES AND BRISK WEST WINDS...WILL LIKELY
NEED TO DOWNGRADE GALE TO SMALL CRAFT ADVISORY THIS EVENING AND RUN
IT THROUGH MONDAY. WAVES WILL DIMINISH WITH OFFSHORE FLOW BUT
WESTERLY GUSTS TO 25 KNOTS EXPECTED DUE TO UNSTABLE CONDITIONS WITH
STRONG COLD ADVECTION CONTINUING BEHIND FRONT LATE TONIGHT AND
MONDAY.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...WIND ADVISORY UNTIL 6 PM CST THIS EVENING FOR WIZ051-057-058-063-
064-068-069.
WIND ADVISORY UNTIL 8 PM CST THIS EVENING FOR WIZ052-059-060-065-
066-070>072.
LM...GALE WARNING UNTIL 9 PM CST THIS EVENING FOR LMZ643>646.
&&
$$
UPDATE...ET/WOOD
TODAY/TONIGHT AND AVIATION/MARINE...CRAVEN
MONDAY THROUGH SATURDAY...MRC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
607 AM CST SUN NOV 11 2012
.SHORT TERM...TODAY
607 AM CST SUN NOV 11 2012
BASED ON THE LAST FEW RUNS OF RAP SOUNDINGS ACROSS THE
REGION...HAVE DECIDED TO PULL THE FREEZING RAIN FROM THE FORECAST
FOR TODAY SINCE IT APPEARS THAT SURFACE TEMPERATURES WILL HAVE A
HARD TIME TO DROP BELOW FREEZING BEFORE THE WARM LAYER COOLS. THIS
MEANS THAT THE RAIN WILL CHANGE OVER TO A PERIOD OF SLEET/SNOW
PELLETS BEFORE CHANGING OVER TO ALL SNOW THIS AFTERNOON/EVENING.
WILL HAVE TO MONITOR THE BACK SIDE OF THE PRECIPITATION SHIELD IN
CASE ICE CREATION IS LOST IN THE -10C TO -20C DENDRITIC GROWTH
ZONE AND SOME DRIZZLE FALLS IN SUB FREEZING AIR.
.LONG TERM...WEDNESDAY THROUGH SATURDAY
313 AM CST SUN NOV 11 2012
HIGH PRESSURE SETS UP ACROSS THE EASTERN HALF OF THE US ON
WEDNESDAY AND LINGERS THROUGH NEXT WEEKEND AND SHOULD LEAVE DRY
CONDITIONS THROUGH THE PERIOD. WITH THE UPPER MISSISSIPPI RIVER
VALLEY BEING ON THE WESTERN PERIPHERY OF THE RIDGE THERE SHOULD BE
SOUTHERLY SURFACE TO LOW LEVEL WINDS THAT WILL KEEP TEMPERATURES
AT ABOUT NORMAL.
&&
.AVIATION...TODAY AND TONIGHT
557 AM CST SUN NOV 11 2012
A STRONG COLD FRONT WILL PUSH ACROSS THE AREA TODAY BRINGING RAIN
TO THE TAF SITES THIS MORNING...SWITCHING OVER TO A MIX OF SLEET
AND SNOW THIS AFTERNOON WITH A SWITCH OVER TO ALL SNOW LATE IN THE
AFTERNOON INTO THE EARLY EVENING HOURS. PLAN ON IFR CONDITIONS
EARLY THIS MORNING AT KRST WITH CLOUD BASES AT 500 FT ALONG WITH LIGHT
RAIN AND BR. IFR CONDITIONS WILL DEVELOP AT KLSE AROUND 14Z AS
RAIN AND LOW CLOUDS MOVE IN WITH CLOUD BASES LOWERING TO AROUND
900 FT. WINDS WILL SWITCH TO THE WEST THEN NORTHWEST AS THE FRONT
MOVES IN. LOOK FOR THE RAIN TO SWITCH OVER TO A MIX OF SLEET AND
SNOW AROUND 19Z AT KRST AND AROUND 22Z AT KLSE. THE PRECIPITATION
SHOULD SWITCH OVER TO ALL SNOW AT KRST BY 21Z WITH IFR CONDITIONS
PERSISTING...WITH CEILINGS AROUND 600 FT AND VISIBILITIES REDUCED
TO AROUND 3SM IN SNOW. THE PRECIPITATION IS EXPECTED TO SWITCH
OVER TO ALL SNOW AT KLSE AROUND 00Z WITH IFR CONDITIONS EXPECTED.
PRECIPITATION WILL FINALLY MOVE EAST OF THE TAF SITE LAT THIS
EVENING WITH MVFR CONDITIONS EXPECTED. WILL HAVE TO KEEP A CLOSE
WATCH ON FREEZING DRIZZLE POTENTIAL THIS EVENING AS ICE ALOFT IS
LOST AND LOW LEVEL MOISTURE AND WEAK LIFT LINGERS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
313 AM CST SUN NOV 11 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...WETENKAMP
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
557 AM CST SUN NOV 11 2012
.SHORT TERM...TODAY THROUGH TUESDAY NIGHT
313 AM CST SUN NOV 11 2012
THE MAIN FOCUS THROUGH EARLY NEXT WEEK IS WITH THE CHANGE OVER
FROM RAIN TO FROZEN PRECIPITATION TODAY AND HOW COLD IT WILL BE
THE NEXT FEW DAYS.
BROAD UPPER LEVEL TROUGHING HAS MOVED INTO THE CENTRAL PLAINS AND
UPPER MISSISSIPPI RIVER VALLEY WITH THE MAIN EMBEDDED CLOSED LOW
CURRENTLY LOCATED IN NORTHEAST MONTANA. AT THE SURFACE...A LOW
PRESSURE SYSTEM HAS MADE IT INTO NORTHERN MINNESOTA WITH A COLD
FRONT TRAILING TO THE SOUTH ALONG AND JUST TO THE WEST OF I-35
FROM MINNESOTA DOWN TO NORTHWEST MISSOURI. HIGH TEMPERATURES HAVE
LIKELY ALREADY BEEN HIT FOR THE DAY WITH COLDER AIR MOVING IN THIS
MORNING. TWO MAIN CORRIDORS OF RAIN SHOWERS AND ISOLATED
THUNDERSTORMS HAVE SET UP WITH ONE EASTERN BAND IN WISCONSIN BEING
IN THE MIDDLE OF THE STRONGEST LOW LEVEL MOISTURE TRANSPORT AND
THE OTHER ASSOCIATED WITH THE SURFACE COLD FRONT. INSTABILITY IS
RATHER LIMITED WITH 11.07Z RAP ANALYSIS SHOWING LESS THAN 250 J/KG
ACROSS THE ENTIRE AREA...SO THUNDERSTORMS SHOULD REMAIN FAIRLY
ISOLATED.
WITH THE EASTERN BAND OF RAIN BEING TO THE EAST OF THE FORECAST
AREA...THE FOCUS IS MORE SO WITH THE WESTERN BAND THAT WILL MOVE IN
ALONG WITH THE COLD FRONT THIS MORNING. 11.00Z NAM/GFS CROSS
SECTIONS RUNNING FROM WEST TO EAST ACROSS THE REGION SHOW
INCREASING FRONTOGENESIS WITH DEEPER LIFT COMING IN AS A RESULT
THIS MORNING ALONG AND BEHIND THE FRONT. WOULD EXPECT THE SCATTERED
COVERAGE TO THE RAIN TO BECOME MORE WIDESPREAD BY MID MORNING.
WITH A PROLONGED PERIOD OF RAIN LASTING THROUGH MUCH OF
TODAY...EXPECT TO SEE RAINFALL AMOUNTS RANGING FROM AROUND A HALF
INCH ON UP TO AN INCH AND A HALF WITH THE HIGHER AMOUNTS MORE
LIKELY ACROSS WESTERN WISCONSIN.
WITH MUCH OF THE PRECIPITATION OCCURRING AFTER THE SURFACE COLD
FRONT COMES THROUGH...IT APPEARS LIKELY THAT TEMPERATURES WILL BE
ABLE TO COOL QUICKLY ENOUGH THAT A CHANGE OVER TO FROZEN
PRECIPITATION WILL OCCUR. 11.00Z NAM/GFS AND 11.06Z RAP SOUNDINGS
SHOW A RAPID NEAR SURFACE LAYER COOLING BEHIND THE FRONT WHILE A
WARM LAYER REMAINS AROUND 850MB. THIS COULD LEAD TO A BRIEF
TRANSITION PERIOD WHERE THE WARM LAYER WILL BE WARM ENOUGH AT +2
TO +4C WITH A NEAR SURFACE COLD LAYER DROPPING DOWN TO AROUND -7C
THAT SOME SLEET AND/OR FREEZING RAIN MAY OCCUR. THE WARM LAYER
RAPIDLY COOLS THOUGH AND CATCHES UP TO WHERE THE FULL THERMAL
PROFILE IS SUB-FREEZING WHILE PRECIPITATION IS STILL OCCURRING.
THIS PERIOD OF ALL SNOW APPEARS TO BE BRIEF AS WELL AT AN HOUR TO
3 HOURS OR SO BEFORE DRIER AIR MOVES IN AND ENDS THE PRECIPITATION.
GIVEN THE SHORT RESIDENCE TIME OF THE FROZEN PRECIPITATION...AM
NOT EXPECTING MUCH IN THE WAY OF ACCUMULATION OF SNOW WITH UP TO A
HALF INCH FALLING. IMPACTS FROM ANY SLEET OR FREEZING RAIN ARE
EXPECTED TO BE MINIMAL AFTER A PROLONGED PERIOD OF RAIN FALLING
BEFORE IT THOUGH SOME SLICK SPOTS CAN NOT BE COMPLETELY RULED OUT.
A COOL CANADIAN AIR MASS WITH THEN DROP DOWN INTO THE REGION
SUNDAY NIGHT INTO MONDAY WITH 850MB TEMPERATURES DROPPING DOWN TO
AROUND -16C BY MONDAY MORNING. WITH SOME BRIEF CLEARING EXPECTED
OVERNIGHT ACROSS NORTHEAST IOWA...COULD SEE SOME SPOTS DROP INTO
THE TEENS. HIGH TEMPERATURES WILL THEN STRUGGLE TO GET ABOVE
FREEZING ON MONDAY WITH THE CORE OF THE COLDEST AIR OVERHEAD ALONG
WITH CLOUDY SKIES. WITH THE LOW LEVEL MOISTURE BEING IN THE
DENDRITIC GROWTH ZONE BUT LIFT BEING WEAK...EXPECT TO SEE FLURRIES
THROUGH MUCH OF THE DAY BEFORE THE TROUGH PROPAGATES TO THE EAST
INTO THE GREAT LAKES. A GRADUAL WARMING TREND WILL THEN KICK OFF
ON TUESDAY WITH LOW LEVEL SOUTHWESTERLY WINDS BRINGING WARMER AIR
INTO THE REGION. THE 11.00Z GFS/ECMWF DO SHOW SOME PRECIPITATION
FORMING ALONG THE NORTHERN FRINGE OF THE LOW LEVEL ADVECTION
TUESDAY NIGHT WHICH SHOULD REMAIN TO THE NORTHWEST OF THE FORECAST
AREA.
.LONG TERM...WEDNESDAY THROUGH SATURDAY
313 AM CST SUN NOV 11 2012
HIGH PRESSURE SETS UP ACROSS THE EASTERN HALF OF THE US ON
WEDNESDAY AND LINGERS THROUGH NEXT WEEKEND AND SHOULD LEAVE DRY
CONDITIONS THROUGH THE PERIOD. WITH THE UPPER MISSISSIPPI RIVER
VALLEY BEING ON THE WESTERN PERIPHERY OF THE RIDGE THERE SHOULD BE
SOUTHERLY SURFACE TO LOW LEVEL WINDS THAT WILL KEEP TEMPERATURES
AT ABOUT NORMAL.
&&
.AVIATION...TODAY AND TONIGHT
557 AM CST SUN NOV 11 2012
A STRONG COLD FRONT WILL PUSH ACROSS THE AREA TODAY BRINGING RAIN
TO THE TAF SITES THIS MORNING...SWITCHING OVER TO A MIX OF SLEET
AND SNOW THIS AFTERNOON WITH A SWITCH OVER TO ALL SNOW LATE IN THE
AFTERNOON INTO THE EARLY EVENING HOURS. PLAN ON IFR CONDITIONS
EARLY THIS MORNING AT KRST WITH CLOUD BASES AT 500 FT ALONG WITH LIGHT
RAIN AND BR. IFR CONDITIONS WILL DEVELOP AT KLSE AROUND 14Z AS
RAIN AND LOW CLOUDS MOVE IN WITH CLOUD BASES LOWERING TO AROUND
900 FT. WINDS WILL SWITCH TO THE WEST THEN NORTHWEST AS THE FRONT
MOVES IN. LOOK FOR THE RAIN TO SWITCH OVER TO A MIX OF SLEET AND
SNOW AROUND 19Z AT KRST AND AROUND 22Z AT KLSE. THE PRECIPITATION
SHOULD SWITCH OVER TO ALL SNOW AT KRST BY 21Z WITH IFR CONDITIONS
PERSISTING...WITH CEILINGS AROUND 600 FT AND VISIBILITIES REDUCED
TO AROUND 3SM IN SNOW. THE PRECIPITATION IS EXPECTED TO SWITCH
OVER TO ALL SNOW AT KLSE AROUND 00Z WITH IFR CONDITIONS EXPECTED.
PRECIPITATION WILL FINALLY MOVE EAST OF THE TAF SITE LAT THIS
EVENING WITH MVFR CONDITIONS EXPECTED. WILL HAVE TO KEEP A CLOSE
WATCH ON FREEZING DRIZZLE POTENTIAL THIS EVENING AS ICE ALOFT IS
LOST AND LOW LEVEL MOISTURE AND WEAK LIFT LINGERS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
313 AM CST SUN NOV 11 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...WETENKAMP
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
343 AM CST SUN NOV 11 2012
.SHORT TERM...
TODAY-FORECAST CONFIDENCE HIGH
STRONG DYNAMIC SETUP COMING UP TODAY. DEEP UPPER TROUGH IN THE
ROCKIES PUSHES OUT INTO THE PLAINS WITH STRONG HEIGHT FALLS THIS
AFTERNOON. 500 MB 12 HOUR FALLS OF 60 TO 80 METERS SPREAD INTO
SOUTHERN WISCONSIN DURING THE AFTERNOON AS SURFACE COLD FRONT
APPROACHES.
ALTHOUGH SURFACE LOW NOT EXPECTED TO DEEPEN AS IT LIFTS INTO
NORTHWEST ONTARIO...VERY STRONG AND DEEP FRONTOGENESIS SHOWN BEHIND
SURGING COLD FRONT. THIS FRONT SHOULD ENTER FAR WEST AROUND NOON
AND THEN PROBABLY JUST EAST OF A LINE FROM FLD TO RFD BY 00Z MON.
BRIEF PERIOD OF NEAR WIND ADVISORY CONDITIONS ALREADY OCCURRED WITH
EARLIER 65 KNOT 850 MB WIND MAX THAT PUSHED THROUGH. MODELS SHOW A
LULL IN LOW LEVEL JET THEN A NEW NARROW SURGED SHOWN JUST AHEAD OF
THE FRONT LATER THIS MORNING INTO THIS AFTERNOON. GFS SHOWS UP TO
80 KNOTS AT 850 MB OVER SHEBOYGAN BY LATE AFTERNOON. WITH MEAN WIND
IN SURFACE TO 850 MB LAYER OF NEARLY 60 KNOTS...CERTAINLY CONCERN
FOR STRONG WIND GUSTS SO WILL GO WITH WIND ADVISORY FOR THE CENTRAL
AND EASTERN PORTIONS OF THE CWA. HRRR SURFACE GUST POTENTIAL
INDICATES 40 KNOTS AND GFS BUFKIT SHOWING SIMILAR GUST POTENTIAL
ESPECIALLY TOWARD THE LAKE SHORE.
RAIN SHOULD SPREAD EAST ALONG WITH A FEW RUMBLES OF THUNDER AND MAY
NOT QUITE REACH LAKE SHORE BY 00Z.
TONIGHT-FORECAST CONFIDENCE HIGH
CONTINUED CRASHING OF UPPER HEIGHTS AS FULL LATITUDE TROUGH CRASHES
THROUGH THE MISSISSIPPI RIVER VALLEY. 500 MB 12 HOUR FALLS OF 180
METERS SPREAD ACROSS SOUTHERN WISCONSIN...HELPING USHER IN MUCH
COLDER AIR.
WINDS SHOULD DIE DOWN BEHIND COLD FRONT SO WILL LET WIND ADVISORY
EXPIRE IN THE WESTERN AREAS AT 00Z AND 02Z IN THE EAST PER
COORDINATION WITH DVN AND LOT WFOS.
RAIN SHOULD END PRIOR TO AIR COOLING ENOUGH FOR CHANGE OVER TO
SNOW. HOWEVER...HAVE A CHANCE OF LIGHT SNOW AT THE TAIL END OF THE
PRECIPITATION BUT GUT FEELING IS THAT PROBABLY IS PRETTY LOW.
ALMOST ALL OF THE GUIDANCE SHOWS THE PRECIP CUTTING OFF RIGHT ABOUT
THE TIME THAT THE 850 MB TEMPERATURE CRASHES TO ZERO OR COLDER.
TREMENDOUS COLD ADVECTION SHOULD DROP WESTERN AREAS INTO THE LOWER
20S BY MORNING DESPITE CLOUD COVER WITH CONSENSUS 850 MB TEMPS DOWN
TO -10C BY 12Z MONDAY.
MONDAY THROUGH MONDAY NIGHT...FORECAST CONFIDENCE MEDIUM.
IT WILL BE A COLD...DRY AND MOSTLY CLOUDY MONDAY. EXPECT CLEARING
BEHIND THE FRONT TO LAST INTO MONDAY MORNING AND THEN INSTABILITY
CLOUDS WITH THE STEEP LOW LEVEL LAPSE RATES IN THE CYCLONIC FLOW
REGIME WILL QUICKLY DEVELOP LATE IN THE MORNING. FLURRIES ARE
POSSIBLE WITH THE AFTERNOON LOW CLOUDS. WINDS WILL BE BRISK OUT OF
THE WEST 15 TO 20 MPH WITH HIGHER GUSTS. MAX TEMPS WILL WILL BE IN
THE LOWER 30S...WITH A FEW LOCATIONS EXPECTED TO STAY BELOW FREEZING.
LINGERING TIGHT PRESSURE GRADIENT ABOVE THE SURFACE WILL ONLY ALLOW
FOR A WEAK INVERSION...THUS KEEPING MIN TEMPS IN CHECK. WITH 925MB
TEMPS AROUND -4C...EXPECT LOWS IN THE LOWER 20S. A FEW LOCATIONS MAY
SEE LOWS IN THE TEENS.
TUESDAY THROUGH THURSDAY...FORECAST CONFIDENCE IS MEDIUM TO HIGH.
HIGH PRESSURE WILL RETURN AND BRING DRY WEATHER FOR MUCH OF THE
REMAINDER OF THIS WEEK. 500MB PATTERN WILL BECOME ZONAL OVER THE
NORTHERN PLAINS AND UPPER GREAT LAKES. A SMALL RIPPLE IN THE FLOW
MAY BRING LIGHT RAIN TO WI TUE NIGHT/WED...BUT IT LOOKS LIKE IT JUST
MIGHT BE INCREASING CLOUDS WITH ISENTROPIC LIFT/WARM AIR ADVECTION.
THE LOW LEVELS ARE EXPECTED TO BE TOO DRY TOO ALLOW FOR ANY
MEASURABLE PRECIP. DRY FORECAST FOR SOUTHERN WI CONTINUES.
TEMPS WILL GRADUALLY WARM THROUGH THE WEEK...BEGINNING AROUND 40 ON
TUESDAY AND ENDING UP AROUND 50 FOR THE WEEKEND.
.LONG TERM...
NEXT WEEKEND...FORECAST CONFIDENCE MEDIUM.
MODELS TRENDED AWAY FROM PRECIP CHANCES IN SOUTHERN WISCONSIN OVER
THE WEEKEND. IT LOOKS LIKE BLOCKING HIGH PRESSURE WILL BE IN CONTROL
WITH DRY WEATHER THROUGH EARLY NEXT WEEK. MAX TEMPS WILL BE AROUND
50.
&&
.AVIATION/12Z TAFS/...
LOW LEVEL SHEAR EARLY THIS MORNING WITH 55 KNOTS AT 2000 FEET AGL
SHOULD RELAX AS SURFACE WINDS INCREASE.
GUSTY SOUTH WINDS TO 35 OR 40 KNOTS EXPECTED ESPECIALLY AT KMKE AND
KENW THIS AFTERNOON AND EARLY EVENING AHEAD OF STRONG COLD FRONT.
PERIOD OF IFR CEILINGS AND VISIBILITIES IN MODERATE TO BRIEFLY HEAVY
RAIN AND RUMBLE OF THUNDER EXPECTED JUST BEHIND COLD FRONT THIS
AFTERNOON IN KMSN AND IN SOUTHEAST TAF SITES LATE AFTERNOON AND
EVENING.
WINDS SHIFT TO WEST AND DIMINISH RAPIDLY BEHIND COLD FRONT THIS
EVENING. CEILINGS SHOULD IMPROVE TO MVFR AFTER RAIN ENDS DURING THE
EVENING AND THEN EVENTUALLY TO VFR AFTER MIDNIGHT AS COLDER AND
DRIER AIR MOVES IN.
NOT IMPOSSIBLE FOR RAIN TO END AS BRIEF PERIOD OF WET SNOW OR SLEET
AT KMSN DURING THE EVENING...BUT NOT MUCH IMPACT EXPECTED WITH
SLIGHTLY ABOVE FREEZING TEMPERATURES.
&&
.MARINE...
ALREADY GUSTING NEAR GALE FORCE EARLY THIS MORNING AT KENOSHA HARBOR
AND EXPECT GALE FORCE SOUTHERLY GUSTS LATER THIS MORNING AND THIS
AFTERNOON AHEAD OF STRONG COLD FRONT. THUS GALE WARNING FOR MID
MORNING INTO THE EVENING LOOKS GOOD.
WINDS SHIFT TO WEST AND DIMINISH RAPIDLY AFTER COLD FRONTAL PASSAGE
THIS EVENING. DUE TO HIGH WAVES AND BRISK WEST WINDS...WILL LIKELY
NEED TO DOWNGRADE GALE TO SMALL CRAFT ADVISORY THIS EVENING AND RUN
IT THROUGH MONDAY. WAVES WILL DIMINISH WITH OFFSHORE FLOW BUT
WESTERLY GUSTS TO 25 KNOTS EXPECTED DUE TO UNSTABLE CONDITIONS WITH
STRONG COLD ADVECTION CONTINUING BEHIND FRONT LATE TONIGHT AND
MONDAY.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...WIND ADVISORY FROM 10 AM THIS MORNING TO 6 PM CST THIS EVENING
FOR WIZ051-057-058-063-064-068-069.
WIND ADVISORY FROM 10 AM THIS MORNING TO 8 PM CST THIS EVENING
FOR WIZ052-059-060-065-066-070>072.
LM...SMALL CRAFT ADVISORY UNTIL 10 AM CST THIS MORNING FOR LMZ643>646.
GALE WARNING FROM 10 AM THIS MORNING TO 9 PM CST THIS EVENING
FOR LMZ643>646.
&&
$$
TODAY/TONIGHT AND AVIATION/MARINE...CRAVEN
MONDAY THROUGH SATURDAY...MRC
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
313 AM CST SUN NOV 11 2012
.SHORT TERM...TODAY THROUGH TUESDAY NIGHT
313 AM CST SUN NOV 11 2012
THE MAIN FOCUS THROUGH EARLY NEXT WEEK IS WITH THE CHANGE OVER
FROM RAIN TO FROZEN PRECIPITATION TODAY AND HOW COLD IT WILL BE
THE NEXT FEW DAYS.
BROAD UPPER LEVEL TROUGHING HAS MOVED INTO THE CENTRAL PLAINS AND
UPPER MISSISSIPPI RIVER VALLEY WITH THE MAIN EMBEDDED CLOSED LOW
CURRENTLY LOCATED IN NORTHEAST MONTANA. AT THE SURFACE...A LOW
PRESSURE SYSTEM HAS MADE IT INTO NORTHERN MINNESOTA WITH A COLD
FRONT TRAILING TO THE SOUTH ALONG AND JUST TO THE WEST OF I-35
FROM MINNESOTA DOWN TO NORTHWEST MISSOURI. HIGH TEMPERATURES HAVE
LIKELY ALREADY BEEN HIT FOR THE DAY WITH COLDER AIR MOVING IN THIS
MORNING. TWO MAIN CORRIDORS OF RAIN SHOWERS AND ISOLATED
THUNDERSTORMS HAVE SET UP WITH ONE EASTERN BAND IN WISCONSIN BEING
IN THE MIDDLE OF THE STRONGEST LOW LEVEL MOISTURE TRANSPORT AND
THE OTHER ASSOCIATED WITH THE SURFACE COLD FRONT. INSTABILITY IS
RATHER LIMITED WITH 11.07Z RAP ANALYSIS SHOWING LESS THAN 250 J/KG
ACROSS THE ENTIRE AREA...SO THUNDERSTORMS SHOULD REMAIN FAIRLY
ISOLATED.
WITH THE EASTERN BAND OF RAIN BEING TO THE EAST OF THE FORECAST
AREA...THE FOCUS IS MORE SO WITH THE WESTERN BAND THAT WILL MOVE IN
ALONG WITH THE COLD FRONT THIS MORNING. 11.00Z NAM/GFS CROSS
SECTIONS RUNNING FROM WEST TO EAST ACROSS THE REGION SHOW
INCREASING FRONTOGENESIS WITH DEEPER LIFT COMING IN AS A RESULT
THIS MORNING ALONG AND BEHIND THE FRONT. WOULD EXPECT THE SCATTERED
COVERAGE TO THE RAIN TO BECOME MORE WIDESPREAD BY MID MORNING.
WITH A PROLONGED PERIOD OF RAIN LASTING THROUGH MUCH OF
TODAY...EXPECT TO SEE RAINFALL AMOUNTS RANGING FROM AROUND A HALF
INCH ON UP TO AN INCH AND A HALF WITH THE HIGHER AMOUNTS MORE
LIKELY ACROSS WESTERN WISCONSIN.
WITH MUCH OF THE PRECIPITATION OCCURRING AFTER THE SURFACE COLD
FRONT COMES THROUGH...IT APPEARS LIKELY THAT TEMPERATURES WILL BE
ABLE TO COOL QUICKLY ENOUGH THAT A CHANGE OVER TO FROZEN
PRECIPITATION WILL OCCUR. 11.00Z NAM/GFS AND 11.06Z RAP SOUNDINGS
SHOW A RAPID NEAR SURFACE LAYER COOLING BEHIND THE FRONT WHILE A
WARM LAYER REMAINS AROUND 850MB. THIS COULD LEAD TO A BRIEF
TRANSITION PERIOD WHERE THE WARM LAYER WILL BE WARM ENOUGH AT +2
TO +4C WITH A NEAR SURFACE COLD LAYER DROPPING DOWN TO AROUND -7C
THAT SOME SLEET AND/OR FREEZING RAIN MAY OCCUR. THE WARM LAYER
RAPIDLY COOLS THOUGH AND CATCHES UP TO WHERE THE FULL THERMAL
PROFILE IS SUB-FREEZING WHILE PRECIPITATION IS STILL OCCURRING.
THIS PERIOD OF ALL SNOW APPEARS TO BE BRIEF AS WELL AT AN HOUR TO
3 HOURS OR SO BEFORE DRIER AIR MOVES IN AND ENDS THE PRECIPITATION.
GIVEN THE SHORT RESIDENCE TIME OF THE FROZEN PRECIPITATION...AM
NOT EXPECTING MUCH IN THE WAY OF ACCUMULATION OF SNOW WITH UP TO A
HALF INCH FALLING. IMPACTS FROM ANY SLEET OR FREEZING RAIN ARE
EXPECTED TO BE MINIMAL AFTER A PROLONGED PERIOD OF RAIN FALLING
BEFORE IT THOUGH SOME SLICK SPOTS CAN NOT BE COMPLETELY RULED OUT.
A COOL CANADIAN AIR MASS WITH THEN DROP DOWN INTO THE REGION
SUNDAY NIGHT INTO MONDAY WITH 850MB TEMPERATURES DROPPING DOWN TO
AROUND -16C BY MONDAY MORNING. WITH SOME BRIEF CLEARING EXPECTED
OVERNIGHT ACROSS NORTHEAST IOWA...COULD SEE SOME SPOTS DROP INTO
THE TEENS. HIGH TEMPERATURES WILL THEN STRUGGLE TO GET ABOVE
FREEZING ON MONDAY WITH THE CORE OF THE COLDEST AIR OVERHEAD ALONG
WITH CLOUDY SKIES. WITH THE LOW LEVEL MOISTURE BEING IN THE
DENDRITIC GROWTH ZONE BUT LIFT BEING WEAK...EXPECT TO SEE FLURRIES
THROUGH MUCH OF THE DAY BEFORE THE TROUGH PROPAGATES TO THE EAST
INTO THE GREAT LAKES. A GRADUAL WARMING TREND WILL THEN KICK OFF
ON TUESDAY WITH LOW LEVEL SOUTHWESTERLY WINDS BRINGING WARMER AIR
INTO THE REGION. THE 11.00Z GFS/ECMWF DO SHOW SOME PRECIPITATION
FORMING ALONG THE NORTHERN FRINGE OF THE LOW LEVEL ADVECTION
TUESDAY NIGHT WHICH SHOULD REMAIN TO THE NORTHWEST OF THE FORECAST
AREA.
.LONG TERM...WEDNESDAY THROUGH SATURDAY
313 AM CST SUN NOV 11 2012
HIGH PRESSURE SETS UP ACROSS THE EASTERN HALF OF THE US ON
WEDNESDAY AND LINGERS THROUGH NEXT WEEKEND AND SHOULD LEAVE DRY
CONDITIONS THROUGH THE PERIOD. WITH THE UPPER MISSISSIPPI RIVER
VALLEY BEING ON THE WESTERN PERIPHERY OF THE RIDGE THERE SHOULD BE
SOUTHERLY SURFACE TO LOW LEVEL WINDS THAT WILL KEEP TEMPERATURES
AT ABOUT NORMAL.
&&
.AVIATION...THROUGH 06Z MONDAY
1127 PM CST SAT NOV 10 2012
COLD FRONT IS CURRENTLY BISECTING MINNESOTA FROM NORTH TO SOUTH.
TAF SITES REMAIN IN THE WARM SECTOR...WHERE CEILINGS WERE
GENERALLY 040K FEET AND HIGHER ALONG WITH A FEW SPRINKLES.
PRESSURE GRADIENT RATHER TIGHT AND BUFKIT SOUNDINGS STILL
SHOWING HIGHER WINDS ALOFT AT 55 TO 60 KNOTS AND THUS CONTINUED
THE LLWS. COLD FRONT POISED TO PUSH THROUGH KRST BETWEEN 12Z-15Z
AND KLSE 15Z-18Z. AS THE FRONT APPROACHES...EXPECT RAIN TO BECOME
MORE WIDESPREAD AND CEILINGS TO LOWER INTO THE IFR CATEGORY AT
BOTH SITES WITH IFR TO LOWER MVFR CEILINGS REMAINING THROUGH MUCH
OF THE DAY. THE RAIN WILL MIX WITH SNOW BEFORE THE PRECIPITATION
ENDS AND LOOKING AT A FEW HOUR WINDOW OF THE MIXED
PRECIPITATION...GENERALLY AROUND 19Z-21Z AT KRST AND AFTER 22Z AT
KLSE. PRECIPITATION WILL END SHORTLY AFTER 00Z FROM WEST TO EAST
WITH MVFR CEILINGS REMAINING THROUGH 06Z.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
313 AM CST SUN NOV 11 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...HALBACH
LONG TERM...HALBACH
AVIATION...RABERDING
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
441 AM EST TUE NOV 13 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 440 AM EST TUE NOV 13 2012
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW UPR TROF OVER THE
GREAT LAKES BTWN RDG OFF THE E COAST AND A MORE ZONAL FLOW OVER WRN
NAMERICA. SINCE THE FASTEST WINDS ALF ARE ON THE E SIDE OF THE UPR
TROF...THIS IS A STRONG SIGNAL THIS TROF IS WEAKENING AND LIFTING TO
THE NE. IN FACT...12Z-24Z H5 HGT RISES IN EXCESS OF 100M AND EVEN
150M OCCURRED OVER MUCH OF THE NCENTRAL CONUS BEHIND THE UPR TROF.
FAIRLY SHARP LLVL CYC WNW FLOW OVER THE GREAT LKS UNDER THE UPR TROF
TRANSITIONS QUICKLY TO A SHARP SFC RDG AXIS OVER MN UNDER THESE HGT
RISES/SUBSIDENCE. BUT QUITE A BIT OF LLVL MSTR LINGERS PER THE 00Z
INL RAOB...SO A LO CLD OVC LINGERS ALL THE WAY W TO THE RDG AXIS.
CLOSER TO HOME...LES RESPSONSIBLE FOR UP TO 6 INCHES OF SN LINGERS
OVER THE W AS OF 06Z...WITH THE MORE PRONOUNCED REFLECTIVITIES FROM
ONTAONGAON TOWARD THE HURON MTNS WHERE SHARP LLVL CNVGC BTWN LARGER
SCALE WNW FLOW OVER THE KEWEENAW AND A MORE WSW LAND BREEZE FLOW OFF
NW WI THAT IS INFLUENCING THE AREA CLOSER TO THE WI BORDER. LATEST
TRENDS SHOW REFLECTIVITIES TENDING TO WEAKEN TO THE W...A SIGN THE
STRONG SUBIDENCE MOVING IN FM THE W MIGHT BE HAVING AN IMPACT. AS
FCST ISSUANCE APRCHS...THE RADAR REFLECTIVIES ARE DIMINISHING
RAPIDLY TO THE W. THE DOMINANT LES BAND THAT WAS OVER ERN LK SUP HAS
MOVED ONSHORE AS OF 09Z BUT HAS WEAKENED QUITE A BIT. WITH
DOWNSLOPING FLOW OF UNMODIFIED AIR...SKIES OVER THE SCENTRAL ARE
MOCLR.
MAIN FCST CONCERNS IN THE SHORT TERM ARE LES TRENDS/GOING HEADLINES
AND POSSIBLE NEED FOR AN ADVY OVER THE ERN CWA NEAR LK SUP THIS MRNG.
TODAY...AREA OF SHARP HGT RISES/DEEP LYR QVECTOR DVGC/SUBSIDENCE TO
THE W ARE FCST TO OVERSPREAD THE UPR GRT LKS AS TROF WEAKENS AND
LIFTS OUT TO THE NE...LEAVING A ZONAL FLOW ALF OVER THE AREA BY LATE
IN THE DAY. WITH ARRIVAL OF SHARP ACYC FLOW/LOWERING SUBSIDENCE
INVRN/DRYING IN THE DGZ...THINK LES WL QUICKLY DIMINISH W-E. GIVEN
THE RADAR TRENDS OVER THE W...OPTED TO CANX ADVY THAT WAS GOING TO
EXPIRE AT 12Z ANYWAY. REMOVED ANY MENTION OF -FZDZ GIVEN SFC DEWPT
DEPRESSIONS OF 5-10F EVEN THOUGH LINGERING LLVL MSTR WL BE CONFINED
BLO THE DGZ. ALTHOUGH THE BANDS COMING ASHORE OVER THE E MIGHT DROP
A COUPLE INCHES OF SN IN A FEW HRS EARLY THIS MRNG... LATEST FCST
PROFILE FM THE LOCAL WRF-ARW FOR GRAND MARAIS IN ALGER COUNTY SHOWS
INVRN BASE SINKING TO NEAR 5K FT BY 12Z WITH DRYING IN THE DGZ.
SINCE THE DOMINANT BAND HAS WEAKENED ALREADY AND THE LES MODE WL
TREND TOWARD A MULTIPLE BAND REGIME IN THE LLVL NW FLOW IN ADVANCE
OF INCOMING SFC RDG AXIS...WL ISSUE SPS TO COVER SOME LOCALLY
HEAVIER SN THIS MRNG AND NOT GO WITH AN ADVY. BY EARLY-MID AFTN...
THE PROFILE OVER THE E IS FCST TO DRY OUT COMPLETELY WITH THE
ARRIVAL OF THE SFC RDG AXIS. OTRW...LINGERING MRNG SC WL GIVE WAY TO
MOSUNNY CONDITIONS WITH THE ARRIVAL OF THE SFC RDG. IN FACT... THE
LLVL FLOW WL SHIFT TO THE SW LATER THIS AFT ONCE THE RDG AXIS SHIFTS
TO THE E.
TNGT...ALTHOUGH THE NGT WL START MOCLR...EXPECT INCRSG MID CLDS IN
THE PREVAILING SW FLOW BTWM DEPARTING SFC RDG AXIS TO THE E AND A
LO PRES TROF ASSOCIATED WITH A SHRTWV MOVING E THRU THE NRN PLAINS
IN THE ZONAL FLOW ALF. THE ISENTROPIC ASCENT IS MOST PRONOUNCED ON
THE 285-290K SFCS /H8-7/. WITH LINGERING DRY AIR BLO THE MID LVL
MOISTENING AND ABSENCE OF ANY OTHER FORCING...EXPECT NO PCPN. EXPECT
LO TEMPS TO OCCUR RELATIVELY EARLY BEFORE THE ARRIVAL OF THE MID CLD.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 440 AM EST TUE NOV 13 2012
UPPER LEVEL PATTERN BECOMING MORE ZONAL AND SPLIT ON WEDNESDAY AS
LONG TERM BEGINS. NORTHERN STREAM TROUGH OVER WESTERN CANADA MOVES
TO THE UPPER GREAT LAKES BY 12Z THURSDAY. GOOD AGREEMENT FROM NWP
ON THE POSITION/DEPTH OF THIS RELATIVELY MINOR TROUGH. WEAK 1.5PVU
ANAMOLY AHEAD OF TROUGH ALONG WITH STEADY H85-H7 WARM AIR ADVECTION
AND A BIT OF MOISTURE ADVECTION AT H85-H7 MAY BE ENOUGH TO KICK OFF
LGT PRECIP ON WEDNESDAY. AMOUNTS WILL BE LIGHT SO WILL ONLY HAVE A
MENTION OF ISOLD RAIN/SNOW SHOWERS AND/OR FLURRIES/SPRINKLES. NO BIG
DEAL AT ALL. MAIN ISSUE WILL BE A CLOUDY SKY LIMITING MAX TEMPS.
PRIMARY LEAD PV ANAMOLY AND 300MB JET STREAK COME ACROSS UPR LAKES
ON WEDNESDAY NIGHT. IF ENOUGH MOISTURE IS PRESENT...MAY BE ABLE TO
SQUEEZE OUT ISOLD SNOW SHOWERS. WORTH A MENTION...ESPECIALLY WITH
ELEVATED H7-H5 LAPSE RATES TOWARD 7 C/KM. SIMILAR FCST ON THURSDAY
WITH TROUGH AXIS OVERHEAD AND BETTER AGREEMENT ON STEEPER MID-LEVEL
LAPSE RATES. DAYTIME HEATING WILL NOT HURT CAUSE EITHER FOR POP-UP
ISOLD RAIN/SNOW SHOWERS AHEAD OF ASSOCIATED SFC TROUGH THAT MOVES
THROUGH THURSDAY EVENING. MOISTURE AVAILABLE TO THE TROUGH MAKES
IT AN OVERALL LOW CHANCE OCCURRENCE AND HAVE KEPT ANY MENTION OUT
OF THIS FCST.
TREND FROM GFS/ECMWF OVER THE LAST FEW RUNS IS TO BECOME MORE
AMPLIFIED WITH THE TROUGH AS IT PROCEEDS TO SLIDE ACROSS REST OF
THE GREAT LAKES BY FRIDAY. CAN REALLY SEE THIS ON THE GFS LOOKING AT
DPROG/DT OF H85 TEMPS OVER LK SUPERIOR AT 00Z FRIDAY. 00Z/12 RUN HAD
TEMPS OF -2C WHILE LATEST RUN HAS -7C. THOUGH RECENT RUNS OF ECMWF
ARE NOT AS COLD AS THE GFS...THE 12Z/11 RUN SHOWED A SIMILAR COLDER
SOLUTION FOR THU NIGHT AND FRIDAY AND THE LATEST RUN HAS TRENDED
COLDER AS WELL. AT THIS POINT...CANNOT COUNT OUT THE COLDER IDEA.
MAY NOT REALLY MATTER THOUGH AS THE MARGINAL MOISTURE TO BEGIN WITH
ON THURSDAY DIMINISHES FURTHER ON THURSDAY NIGHT. SPIKE OF 925MB
MOISTURE ON GFS/ECMWF INDICATE SCT CLOUDS COULD OCCUR CLOSER TO LK
SUPERIOR WITH SOME OVER-WATER INSTABILITY. ON THE FLIP SIDE...UPPER
HEIGHTS RISING SHARPLY THROUGH FRIDAY RESULTS IN SYNOPTIC SUBSIDENCE
SQUASHING INVERSION BLO H9 BY AFTN. DOES NOT APPEAR TO BE VERY GOOD
SETUP TO SEE ANYTHING BUT SCT LAKE EFFECT CLOUDS ON THURSDAY NIGHT
FOR A TIME.
IN WAKE OF TROUGH HIGH PRESSURE BUILDS RIGHT BACK IN FOR FRIDAY
THROUGH NEXT WEEKEND. EXPECT DRY WEATHER WITH TEMPS WARMING SLIGHTLY
ABOVE NORMAL FOR DAYTIME HIGHS. FORECAST SOUNDINGS OFF GFS HINT AT
LOW-LEVEL MOISTURE AND SHALLOWER INVERSION. IF THESE SIGNALS ARE
CORRECT MAY EVEN SEE SOME FOG/STRATUS FRIDAY NIGHT. IF THESE SIGNALS
ARE BOGUS THEN MAX TEMPS FROM SATURDAY THROUGH MONDAY COULD REACH
UPR 40S TO LOW-MID 50S WHICH IS 10-15F DEGREES ABOVE NORMAL.
NIGHTTIME LOWS ABOVE NORMAL TOO WITH READINGS MOSTLY ABOVE FREEZING.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1228 AM EST TUE NOV 13 2012
KIWD...EXPECT MVFR LAKE CLOUDS TO LIFT BY LATE TUE MORNING AS WINDS
SHIFT FROM WRLY TO SWRLY. VFR CONDITIONS ARE THEN EXPECTED THROUGH
THE REST OF THE FCST PD.
KCMX...BEST LES BANDS HAVE SHIFTED SOUTH OF THE KEWEENAW PENINSULA.
LOOK FOR FLURRIES TONIGHT WITH PREVAILING VFR CONDITIONS AS DRIER
AIR AND RDGG WILL BE MOVING IN FM NW OF THE LAKE. SOME LOWERING OF
INVERSION HGTS MAY BRIEFLY BRING CIGS BACK DOWN TO MVFR AROUND
SUNRISE BEFORE WINDS BACK FM WEST TO SOUTHWEST ALLOWING FOR VFR
CONDITIONS FOR THE REST OF THE FCST PD.
KSAW...EXPECT VFR CONDITIONS THROUGH THE FCST PD AS WINDS SHIFT FROM
WSW TONIGHT TO SSW ON TUESDAY.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 440 AM EST TUE NOV 13 2012
WESTERLY WINDS TO 30 KTS DIMINISH TO LESS THAN 25 KTS BY EVENING AS
PRESSURE GRADIENT GRADUALLY RELAXES DUE TO HIGH PRESSURE BUILDING
FROM THE OHIO VALLEY INTO THE GREAT LAKES. ON WEDNESDAY THE HIGH
MOVES EAST WHILE SFC TROUGH MOVES ACROSS NORTHERN ONTARIO. EXPECT
SOUTH WINDS TO INCREASE TO 30 KTS...MAINLY OVER EASTERN SECTIONS.
SMALL RISK FOR GALE GUSTS. SOUTH TO SOUTHWEST WINDS REMAIN UP TO 25
KTS THROUGH THURSDAY. SFC TROUGH COMES ACROSS THURSDAY NIGHT. WINDS
IN WAKE OF TROUGH SHIFT NORTH BY FRIDAY MORNING BUT QUICKLY DIMINISH
TO LESS THAN 20 KTS BY FRIDAY AFTERNOON WITH HIGH PRESSURE BUILDING
ACROSS REGION. EXPECT THE HIGH TO SLOWLY DRIFT TO THE NORTHEAST
THROUGH THE FIRST PART OF NEXT WEEK KEEPING WINDS LESS THAN 20 KTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...VOSS
MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1229 AM EST TUE NOV 13 2012
.UPDATE...
ISSUED AT 924 PM EST MON NOV 12 2012
MAIN UPDATE CONCERN DEALS WITH HEAVIER SNOW BAND WHICH HAS REACHED
INTO THE NORTHERN PORTION OF BARAGA COUNTY THIS EVENING PER MQT
RADAR LOOP. SPOTTER REPORTS FROM NEAR PELKIE TO BARAGA HAVE COME IN
WITH BETWEEN 2 AND 3 INCHES THUS FAR. GIVEN THAT RADAR CONTINUES TO
SHOW 30 DBZ REFLECTIVITY RETURNS WITH SNOW BAND OVER NW BARAGA
COUNTY AND THAT MESOSCALE MODELS SUGGEST POTENTIAL FOR THIS SNOW TO
CONTINUE FOR AT LEAST A FEW MORE HRS...DECIDED TO INCLUDE BARAGA
COUNTY IN WINTER WX ADVISORY FOR 2 TO 5 INCHES OF SNOW. HEAVIER SNOW
HAS TAPERED OFF OVER THE KEWEENAW PENINSULA WITH MAIN BAND NOW
SHIFTING SOUTH OVER NRN ONTONAGON...SRN HOUGHTON AND BARAGA
COUNTIES. LOOK FOR SNOW TO TAPER OFF LATE TONIGHT AS RDGG MOVES IN
FM THE WEST AND SUBSIDENCE INVERSION LOWERS FROM NEAR 8KFT TO BLO
5KFT.
&&
.SHORT TERM...(THIS EVENING THROUGH TUESDAY)
ISSUED AT 405 PM EST MON NOV 12 2012
WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A HIGH AMPLITUDE BUT
WEAKENING TROF EXTENDING FROM NRN ONTARIO THRU THE MISSISSIPPI
VALLEY. UNDERNEATH TROF EARLIER TODAY...12Z SOUNDINGS AT KINL/KMPX
SHOWED A DEEP MOISTURE PROFILE WITH 850MB TEMPS AROUND -15C WHICH
WILL ALLOW FOR A NICE INTERSECTION OF LAKE CONVECTION THRU THE DGZ.
SO...CONDITIONS ARE FAVORABLE FOR MDT/HVY LAKE EFFECT/LAKE ENHANCED
SNOW AS MID LEVEL TROF CONTINUES TO MOVE ACROSS THE UPPER GREAT
LAKES LATE THIS AFTN/EVENING. AS EXPECTED...A DOMINANT LES BAND
DEVELOPED OVER WRN LAKE SUPERIOR EARLIER TODAY BTWN THE MN NORTH
SHORE AND WISCONSIN`S BAYFIELD PENINSULA. WITH MID LEVEL TROF
PASSING...WINDS OVER WRN LAKE SUPERIOR ARE NOW VEERING MORE WRLY...
SO THIS DOMINANT LES BAND IS ADJUSTING TO THE CHANGING WIND...BUT IT
IS ALSO BECOMING LESS ORGANIZED...WHICH MAY BE PARTLY DUE TO
NEGATIVE DIURNAL AFFECTS. KMQT/KDLH AND ENVIRONMENT CANADA RADAR
LOCATED JUST N OF THUNDER BAY ALL INDICATE AREAS OF HEAVY LES NOW
NEARING THE WRN SHORE OF THE KEWEENAW. KDLH RADAR IS STILL SHOWING
RETURNS AS HIGH AS AROUND 12KFT...SO LAKE EFFECT CONVECTION REMAINS
DEEP WITH POCKETS OF VERY HVY SNOW. AHEAD OF THE HEAVIER SNOW...SHSN
HAVE BEEN AFFECTING PORTIONS OF THE KEWEENAW TODAY. HOWEVER...ONLY
WEBCAM THAT HAS CONSISTENTLY SHOWN SHARPLY REDUCED VIS AT TIMES IS
LOCATED ALONG THE SHORE WEST OF EAGLE RIVER.
FCST THINKING HASN`T CHANGED MUCH WITH REGARD TO LES AND HEADLINES
TONIGHT. DEEP MOISTURE AND FAVORABLE TEMP PROFILE ARGUES FOR MDT TO
HVY SNOW AT TIMES AS MID LEVEL TROF PASSES TONIGHT. BULK OF SNOW
ACCUMULATIONS ON THE KEWEENAW PENINSULA WILL OCCUR OVER THE NEXT
SEVERAL HRS AS WIND SHIFT/CONVERGENCE ZONE OVER THE WRN LAKE DROP S
ACROSS THE PENINSULA. MAY SEE SNOWFALL RATES BRIEFLY AS HIGH AS
2-4IN/HR. AFTER THE CONVERGENCE ZONE PASSES...WIND PARALLEL BANDS
WITH MUCH MORE VARIABLE SNOW INTENSITY WILL SET UP FOR THE REMAINDER
OF THE EVENING. LES WILL THEN QUICKLY DIMINISH OVERNIGHT AS SHARP
HEIGHT RISES OCCUR IN THE WAKE OF MID LEVEL TROF (180-200M HEIGHT
RISES AT 500MB BTWN 00Z AND 12Z)...INVERSION QUICKLY DROPS TO 4-5KFT
AND CONVECTIVE LAYER BEGINS TO FALL BLO THE DGZ. GIVEN THE SHORT
RESIDENCE TIME OF THE CONVERGENCE ZONE OVER THE KEWEENAW...AND
RATHER QUICK DIMINISHING TREND THRU THE NIGHT...HAVE LOWERED SNOW
AMOUNTS BY AN INCH OR TWO. MAX AMOUNTS WILL PROBABLY BE IN THE 4-5
INCH RANGE OVER THE HIGH TERRAIN.
FARTHER S...CONVERGENCE ZONE WILL SINK S AND AFFECT ONTONAGON/SRN
HOUGHTON COUNTIES THIS EVENING. ALTHOUGH PREVIOUSLY DISCUSSED
NEGATIVE FACTORS TAKE HOLD DURING THE NIGHT TO DIMINISH LES
INTENSITY...LOW-LEVEL WINDS WILL MAINTAIN A CONVERGENT LOOK AS WSW
LAND BREEZE ENHANCED WINDS OFF NW WI CONVERGE WITH WNW FLOW OVER
LAKE SUPERIOR. THIS SHOULD HELP TO AT LEAST MAINTAIN MORE PERSISTENT
THOUGH WEAKENING LES ACROSS ONTONAGON/SRN HOUGHTON COUNTIES AND
PROBABLY A SMALL PART OF GOGEBIC COUNTY N OF M-28 THRU THE NIGHT.
WILL RETAIN ADVY FOR ONTONAGON/SRN HOUGHTON COUNTIES TONIGHT.
TO THE E...WIND SHIFT/CONVERGENT BAND WILL EVENTUALLY MOVE ONSHORE
OVER THE NE FCST AREA TONIGHT. HOWEVER...BY THE TIME IT DOES...DEEP
MOISTURE WILL BE EXITING WITH SHARP HEIGHT RISES OCCURRING. SO...
WHILE THERE WILL LIKELY BE A BRIEF PERIOD OF MDT/HVY SNOW ON WIND
SHIFT...LES THAT ORGANIZES BEHIND TROF WILL NOT BE SUBSTANTIAL. WILL
PAINT 1-3 INCH ACCUMULATIONS ACROSS ALGER COUNTY E OF MUNISING AND
NRN LUCE COUNTY TONIGHT.
LINGERING LES WILL QUICKLY WIND DOWN/END FROM W TO E TUE. MIGHT SEE
AN ADDITIONAL INCH OF SNOW OVER ERN ALGER/NRN LUCE COUNTY IN THE
MORNING. OTHERWISE...LOOK FOR DECREASING CLOUDS FROM SW TO NE AS
WINDS BACK TO THE SW.
.LONG TERM...(TUESDAY NIGHT THROUGH MONDAY)
ISSUED AT 405 PM EST MON NOV 12 2012
UPPER TROUGH THAT HAS LED TO THE UNSETTLED WEATHER THIS WEEKEND AND
TODAY WILL BE SHIFTING EAST OF THE UPPER GREAT LAKES ON TUESDAY
NIGHT. THIS WILL LEAD TO THE START OF SPLIT FLOW ACROSS MUCH OF THE
COUNTRY...WHICH WILL REALLY BECOME ESTABLISHED ON BY THE WEEKEND
BEHIND A WEAKER TROUGH MOVING THROUGH THE NORTHERN STREAM WEDNESDAY
INTO FRIDAY. THIS WILL LEAD TO A FAIRLY QUIET PATTERN ACROSS THE
UPPER GREAT LAKES FOR THE LONG TERM PERIOD.
HIGH PRESSURE RIDGE WILL BE OVER THE AREA AT THE START OF THE LONG
TERM PERIOD FROM HIGH PRESSURE CENTERED OVER THE LOWER GREAT LAKES
AND OHIO RIVER VALLEY. MOSTLY CLEAR SKIES TO START THE EVENING WILL
QUICKLY GIVE WAY TO INCREASING CLOUDS OVER THE WEST/CENTRAL...WHILE
ANY LINGERING LAKE EFFECT SHOWERS SHOULD BE PUSHING NE OVER EASTERN
LAKE SUPERIOR. THESE CLOUDS ARE IN ADVANCE OF A WEAK SHORTWAVE AND
WARM AIR ADVECTION THAT WILL MOVE ACROSS THE WESTERN CWA WEDNESDAY.
MODELS ARE CONSISTENT ON MOST OF THE MOISTURE STAYING ABOVE
H800...WITH BROAD AND WEAK LIFT ASSOCIATED WITH IT. THERE IS SOME
DRY AIR BELOW H800...BUT NOTHING TOO SUBSTANTIAL...SO THINK THAT
ANY PRECIPITATION THAT DOES FALL WILL MAKE IT TO THE SURFACE. WITH
THE BEST FORCING OVER WESTERN LAKE SUPERIOR...EXPECT THAT AREA TO
HAVE THE BEST CHANCE OF SHOWERS...SO HAVE SPREAD THE SLIGHT CHANCES
FARTHER SOUTH TO COVER MUCH OF WESTERN LAKE SUPERIOR ON WEDNESDAY.
OTHERWISE...THE MID CLOUDS WILL COVER THE REST OF THE CWA WITH ONLY
AN ISOLATED FLURRY OVER WESTERN UPPER MICHIGAN.
ONE OTHER ITEM OF NOTE FOR LATE TUESDAY NIGHT AND INTO WEDNESDAY
IS THE POTENTIAL FOR LAKE EFFECT PRECIPITATION OFF LAKE MICHIGAN.
DELTA T VALUES AROUND 15 WOULD SUPPORT LAKE ENHANCED PRECIPITATION
UNDER THE SLOWLY BACKING WINDS FROM SW TO SOUTHERLY ON WEDNESDAY.
MAIN LIMITING FACTOR APPEARS TO BE INVERSION HEIGHTS AROUND
4-5KFT. THERE ARE SOME HINTS IN THE MODELS THAT THIS INVERSION COULD
WEAKEN AS THE DEEPER MOISTURE ARRIVES AND LEAD TO AN INCREASE IN
INTENSITY. THIS LOOKS TO BE FAIRLY SHORT LIVED...AS DRIER
AIR BETWEEN H875-700 AND WAA MOVES BACK IN DURING THE AFTERNOON AND
DIMINISHES THE CHANCES AGAIN. WILL CONTINUE TO MENTION THE SLIGHT
CHANCES FOR THIS POTENTIAL...BUT SEEMS TO BE FAIRLY LIMITED.
THE SHORTWAVE MOVES AWAY FROM THE AREA WHILE A LOW PRESSURE SYSTEM
MOVES INTO HUDSON BAY. THIS SHOULD LEAD TO INCREASING SOUTHERLY
FLOW AHEAD OF A WEAK COLD FRONT MOVING INTO WESTERN ONTARIO. EXPECT
MID CLOUDS TO INCREASE AHEAD OF THIS FRONT ON WEDNESDAY
NIGHT...ESPECIALLY OVER THE NORTH HALF OF THE CWA. BOTH NAM/SREF
INDICATING INCREASED PROBABILITIES OF FOG OVER THE WEST...BUT THE
NAM HAS THINNER MID CLOUDS...WHICH WOULD LEAD BETTER RADIATIONAL
COOLING AND FOG POTENTIAL. WITH THE DIFFERENCES DIFFERENCES
IN THE MID CLOUDS...WILL LEAVE FOG MENTION OUT OF THE FORECAST DUE
TO THE POTENTIAL FOR MID CLOUDS.
DECAYING FRONTAL BOUNDARY WILL BE MOVING ACROSS THE NORTHERN HALF OF
THE CWA ON THURSDAY. THIS WILL LARGELY BE MARKED BY A WIND SHIFT AND
CLOUDS WHILE THE PRECIPITATION WILL STAY TO THE NORTH OF LAKE
SUPERIOR AND CLOSER TO THE BETTER FORCING/MOISTURE.
BEHIND THIS FRONTAL BOUNDARY AND WEAK UPPER TROUGH...SPLIT FLOW
REALLY SETTLES OVER THE NORTHERN HALF OF THE CONUS. THE SOUTHERN
STREAM JET LOOKS TO REMAIN OVER THE SOUTHERN TIER OF STATES...WHILE
THE NORTHERN STREAM RIDGES OVER NORTHERN CANADA. THIS SHOULD LEAD TO
A VERY QUIET AND LIKELY ABOVE NORMAL TEMPERATURE PERIOD FOR UPPER
MICHIGAN INTO NEXT WEEK. AT THE SURFACE...HIGH PRESSURE WILL SETTLE
OVER THE GREAT LAKES REGION FOR THURSDAY NIGHT INTO SATURDAY BEFORE
MOVING EAST INTO QUEBEC FOR SUNDAY AND MONDAY. DRY AIR ASSOCIATED
WITH THIS HIGH SHOULD PRODUCE DECREASING CLOUDS ON THURSDAY NIGHT
AND FRIDAY AND THEN PARTLY CLOUDY TO MOSTLY CLEAR SKIES INTO NEXT
WEEK. BIGGEST QUESTION WILL BE THE TEMPERATURES...AS THEY WILL
DEPEND ON HOW DEEP THE MIXING WILL BE. BOTH GFS/ECMWF INDICATING
H850 TEMPS RISING TOWARDS 1-2C THIS WEEKEND...BUT BOTH ARE
STRUGGLING TO MIX THOSE TEMPS TO THE SURFACE. WILL GO WITH THE
MIDDLE GROUND SINCE IT IS SO FAR OUT...HIGHS IN THE MID-UPPER
40S...BUT IF WE CAN TAP INTO THE WARMER TEMPS ALOFT...COULD EASILY
SEE HIGHS IN THE 50S AT THE FIRST PART OF NEXT WEEK.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT)
ISSUED AT 1228 AM EST TUE NOV 13 2012
KIWD...EXPECT MVFR LAKE CLOUDS TO LIFT BY LATE TUE MORNING AS WINDS
SHIFT FROM WRLY TO SWRLY. VFR CONDITIONS ARE THEN EXPECTED THROUGH
THE REST OF THE FCST PD.
KCMX...BEST LES BANDS HAVE SHIFTED SOUTH OF THE KEWEENAW PENINSULA.
LOOK FOR FLURRIES TONIGHT WITH PREVAILING VFR CONDITIONS AS DRIER
AIR AND RDGG WILL BE MOVING IN FM NW OF THE LAKE. SOME LOWERING OF
INVERSION HGTS MAY BRIEFLY BRING CIGS BACK DOWN TO MVFR AROUND
SUNRISE BEFORE WINDS BACK FM WEST TO SOUTHWEST ALLOWING FOR VFR
CONDITIONS FOR THE REST OF THE FCST PD.
KSAW...EXPECT VFR CONDITIONS THROUGH THE FCST PD AS WINDS SHIFT FROM
WSW TONIGHT TO SSW ON TUESDAY.
&&
.MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 405 PM EST MON NOV 12 2012
A TIGHT PRESSURE GRADIENT BETWEEN THE FRONT THAT MOVED THROUGH LAST
NIGHT AND ANOTHER SURFACE TROUGH MOVING THROUGH NORTHERN MN WILL
KEEP WINDS IN THE 20-30KT RANGE TONIGHT AS THEY SHIFT TO A MORE
NORTHWESTERLY DIRECTION. THERE COULD ALSO BE A FEW GALE FORCE GUSTS
TO 35 KNOTS TONIGHT...MAINLY OVER THE EASTERN HALF OF LAKE SUPERIOR.
A WEAK HIGH PRESSURE RIDGE WILL MOVE ACROSS LAKE SUPERIOR ON TUESDAY
NIGHT AND LEAD TO WINDS WEAKENING BELOW 25KTS. A LOW PRESSURE SYSTEM
MOVING INTO HUDSON BAY WILL BRING A TIGHTENING PRESSURE GRADIENT
OVER LAKE SUPERIOR...WHICH WILL INCREASE WINDS OUT OF THE SOUTHWEST
TO 20-30KTS OVER EASTERN LAKE SUPERIOR ON WEDNESDAY INTO WEDNESDAY
EVENING. HIGH PRESSURE WILL THEN SETUP OVER THE GREAT LAKES REGION
ON THURSDAY NIGHT AND SLOWLY DRIFT TO THE NORTHEAST THROUGH THE
FIRST PART OF NEXT WEEK. THIS WILL LEAD TO WINDS STAYING BELOW
20KTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR
MIZ001>004-084.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...VOSS
SHORT TERM...ROLFSON
LONG TERM...SRF
AVIATION...VOSS
MARINE...SRF
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1139 PM EST MON NOV 12 2012
.SYNOPSIS...
HIGH PRESSURE WILL BEGIN BUILDING INTO THE AREA FROM THE
SOUTHWEST TONIGHT AND THEN MOVE OVER THE AREA TUESDAY AND
WEDNESDAY. THE HIGH PRESSURE CENTER WILL MOVE NORTHEAST OF THE
AREA...BUT WILL CONTINUE TO RIDGE OVER THE AREA THROUGH THE
SECOND HALF OF THE WEEK.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
UPDATE...WILL UPDATE ONE MORE TIME FOR CLOUD AND PRECIP TRENDS.
PREVIOUS...THE COLD FRONT THAT MOVED THROUGH THE AREA TODAY IS
MOVING OUT OF THE FORECAST AREA AS OF 20Z. RAIN WILL CONTINUE
ESPECIALLY ACROSS THE EASTERN HALF OF THE AREA THROUGH THE
REMAINDER OF THE AFTERNOON AND EVENING. MEANWHILE...THERE IS A
SHARP CUTOFF TO BOTH PRECIP AND CLOUDS ACROSS THE WEST WITH
SATELLITE SHOWING CLEARING MOVING INTO NW OH ALREADY THIS
AFTERNOON. OBS HAVE SHOWN A MIX OF RAIN AND SNOW ACROSS WESTERN
COUNTIES BUT RAIN ELSEWHERE. MADE ONLY SMALL ADJUSTMENTS TO POPS
THROUGH EARLY TONIGHT WITH THE RAIN CONTINUING TO PUSH EASTWARD
AND DECREASING POPS FROM WEST TO EAST. WITH THAT MENTION ONLY CHC
POPS ACROSS THE WEST FOR EARLY TONIGHT...THEN DRY AFTER MIDNIGHT.
ONCE THIS AREA OF SHOWERS DEPARTS TO THE EAST THE FOCUS WILL BE ON
LAKE EFFECT SNOW SHOWERS. WITH H850 TEMPS DROPPING DOWN TO -8C OR
SO AND INVERSIONS SHOWN ON BUFKIT SOUNDING STILL A BIT HIGH
EXPECTING LINGERING CLOUDS WITH WEST WINDS ACROSS NE OH AND NW PA
AFTER MIDNIGHT TONIGHT. THINKING THAT WITH THE AMOUNT OF DRIER AIR
BUILDING IN THIS WILL LIMIT LAKE EFFECT SNOW DEVELOPMENT AND WILL
HAVE TO WAIT FOR SOME ADDITIONAL SUPPORT LATE OVERNIGHT.
WATER VAPOR AND MODELS SHOWING SHARPER UPPER TROUGH THAT IS
EXPECTED TO SWING ACROSS THE SOUTHERN GREAT LAKES LATE OVERNIGHT
AND TUESDAY MORNING. EXPECTING THIS TO HELP IN GETTING SOME LAKE
EFFECT SNOW ACROSS NE OH AND NW PA. ELSEWHERE EXPECTING PARTLY
CLOUDY SKIES. USED A BLEND OF MET AND MAV TEMPS WITH HRRR TRENDS
IN THE VERY SHORT TERM ON HOURLY TEMPS.
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY NIGHT/...
GUIDANCE POPS NOT INDICATING MUCH WITH LAKE EFFECT SNOW
SHOWERS...BUT WENT WITH AT LEAST HIGH CHC POPS ACROSS NE OH AND NW
PA TUESDAY MORNING. WITH THE WEST FLOW NOT EXPECTING MUCH ACROSS
GREATER CLEVELAND AREA...WITH BEST ACCUMS STRETCHING FROM CENTRAL
ASHTABULA COUNTY INTO INTERIOR ERIE COUNTY. THINKING FURTHER SOUTH
THROUGH CRAWFORD COUNTIES AMOUNTS WILL DIMINISH. BETTER SFC
CONVERGENCE OFF THE LAKE APPEARS TO BE IN THIS AREA ALSO. OVERALL
THOUGH THINKING ACCUMS WILL RANGE AROUND AN INCH OR SO ACROSS
INTERIOR NW PA TO LESS THAN AN INCH BACK INTO FAR NE OH COUNTIES.
BY AFTERNOON THE TROUGH PUSHES TO THE EAST AND DRIER AIR OVERCOMES
THE LAKE EFFECT POTENTIAL. SOME LINGERING CLOUDS AND PERHAPS SOME
FLURRIES POSSIBLE ACROSS HIGHER ELEVATIONS OF NW PA...BUT NOT
EXPECTING ANY FURTHER ACCUMS. FOR THE REMAINDER OF THE AREA HIGH
PRESSURE INFLUENCE WILL HELP ALLOW FOR SUNSHINE. TEMPS EXPECTED TO
RANGE IN MID TO UPPER 30S ACROSS THE NORTHEAST WITH CLOUDS AND AM
SNOW SHOWERS...TO LOWER 40S ACROSS THE SOUTH AND WEST.
FROM TUESDAY NIGHT THROUGH THURSDAY NIGHT HIGH PRESSURE IS
EXPECTED TO BE IN CONTROL ACROSS THE AREA WITH DRY CONDITIONS.
SOME ISSUES WITH CLOUD COVER THROUGH THE PERIOD AS MODELS
CONTINUING TO SHOW SOME WEAK UPPER TROUGHS MOVING THROUGH THE
UPPER FLOW DURING THE PERIOD. DESPITE THAT MAINLY QUIET WEATHER
WITH TEMPS TRENDING TOWARD NORMAL ARE EXPECTED. LEANED TOWARD A
BLEND OF MET MAV AND MEX NUMBER THROUGH THE PERIOD AS SEEING NO
REASON TO DEVIATE MUCH WITH HIGH PRESSURE INFLUENCE.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
HIGH PRESSURE WILL BE THE DOMINANT FEATURE THROUGH THE EXTENDED EVEN
AS THE CENTER OF IT DRIFTS INTO EASTERN QUEBEC PROVINCE. SO AT THIS
POINT WE EXPECT TO SEE DRY CONDITIONS. THERE MAY BE A SLIGHT
INCREASE IN CLOUD COVER ON SUNDAY AS A STORM SYSTEM TAKES SHAPE OFF
THE MIDDLE ATLANTIC COAST. OTHERWISE EXPECT TO SEE TEMPERATURES NEAR
TO SLIGHTLY BELOW AVERAGE THROUGH THE PERIOD.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
WRAP AROUND MOISTURE AND UPPER TROUGH WILL MAINTAIN CLOUDY SKIES
INTO TUESDAY AFTERNOON. FORTUNATELY EXPECTING THESE TO PRIMARILY BE
LOW END VFR. EXCEPTION WOULD BE WITH ANY SCATTERED LAKE
EFFECT/ENHANCED SNOW SHOWERS ACROSS THE HIGHER TERRAIN LOCATIONS
EAST OF CLEVELAND. NEAR THE IMMEDIATE LAKESHORE LIKELY STILL RAIN.
BUT THE BEST MOISTURE STAYS TO OUR NORTH. WILL MENTION A SNRA MIX
FOR ERIE IN A TEMPO...BUT THAT IS IT. FORECAST SOUNDING PROFILES
ARE NOT SUGGESTING MUCH WITH THE LACK OF DEEPER MOISTURE. WINDS
SHIFT TO THE NORTHWEST TUESDAY AFTERNOON. HIGH PRESSURE FOLLOWS
FOR TUESDAY NIGHT.
OUTLOOK...SOME NON-VFR POSSIBLE FRIDAY.
&&
.MARINE...
THE COLD FRONT IS JUST EAST OF THE FORECAST AREA. WINDS DIE DOWN
BEHIND THE FRONT BUT AS THE MUCH COLDER AIR MOVES OVER THE LAKE
INCREASED MIXING WILL OCCUR OVER THE LAKE. THE 850MB TEMPS FORECAST
TO DIP TO MINUS 10C BY DAYBREAK TUESDAY. AS A RESULT THE SMALL
CRAFT WILL BE NEEDED OVER THE LAKE THROUGH THE OVERNIGHT HOURS.
THE WINDS WILL DIE DOWN SIGNIFICANTLY BY TOMORROW AFTERNOON AS
HIGH PRESSURE BUILDS OVER THE LAKE. EXPECT CONDITIONS TO REMAIN
BELOW SMALL CRAFT ADVISORY CRITERIA THROUGH THE WEEKEND AS HIGH
PRESSURE WILL REMAIN OVER THE LAKE.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 AM EST TUESDAY FOR LEZ145>149.
SMALL CRAFT ADVISORY UNTIL 4 AM EST TUESDAY FOR LEZ142>144.
&&
$$
SYNOPSIS...ABE
NEAR TERM...ABE/TK
SHORT TERM...ABE
LONG TERM...MULLEN
AVIATION...OUDEMAN
MARINE...DJB/OUDEMAN
AREA FORECAST DISCUSSION
NWS MEDFORD OR
824 PM PST MON NOV 12 2012
.DISCUSSION...A COLD FRONT REMAINS OVER SW OREGON AND NORTHERN
CALIFORNIA THIS EVENING. IT IS WEAKENING AND WASHING OUT AS
EXPECTED, BUT LIGHT RAIN CONTINUES AT MANY LOCATIONS, ESPECIALLY
THE CURRY COAST, WESTERN SISKIYOU COUNTY, AND IN THE CASCADES. THE
MOISTURE IS CONFINED TO THE LOW LEVELS AND THUS THE RADAR IS
OVERSHOOTING MUCH OF IT, BUT THERE ARE CERTAINLY STILL SHOWERS
FLOATING AROUND OTHER LOCATIONS AS WELL. THE 13/00Z RUNS OF THE
NAM AND RAP SHOW THIS CONTINUING FOR A WHILE TONIGHT. AS A RESULT,
I HAVE ALREADY UPDATED THE FORECAST TO INCREASE POPS FOR THIS
EVENING THROUGH EARLY TOMORROW MORNING, MOSTLY CASCADES AND
SISKIYOUS WESTWARD. I`VE CONFINED THE HIGHEST POPS TO THE COAST
AND MOUNTAINS BUT IT SHOULD NOT COME AS A SURPRISE TO SEE A BRIEF
SHOWER OR TWO NEARLY ANYWHERE THIS EVENING. RAIN IS FAIRLY LIGHT
(ONLY A FEW HUNDREDTHS AN HOUR AT MOST), AND SO, DESPITE
INCREASING POPS, I ACTUALLY DECREASED AMOUNTS. THE REST OF THE
FORECAST STILL LOOKS GOOD. -WRIGHT
&&
.AVIATION...A FRONT IS STALLING AND WEAKENING OVER SOUTHWESTERN
OREGON...AND BRINGING A MIX OF MVFR...IFR...AND VFR CEILINGS TO
AREAS ALONG AND WEST OF THE CASCADES. MOUNTAIN OBSCURATION WILL
IMPACT ALL AREAS TONIGHT. FOG AND IFR CEILINGS WILL LIKELY AFFECT
WEST SIDE VALLEYS LATE TONIGHT...WITH VFR CONDITIONS AT MOST EAST
SIDE TERMINALS. CONDITIONS SHOULD TRANSITION TO VFR ALL AREAS BY
EARLY TUESDAY AFTERNOON. SK
&&
.PREV DISCUSSION... /ISSUED 300 PM PST MON NOV 12 2012/
SHORT TERM...TONIGHT THROUGH THURSDAY NOVEMBER 15TH.
A WARM FRONT LIFTED NORTHEAST ACROSS THE AREA THIS MORNING AND
THE TRAILING COLD FRONT HAS GENERATED LIGHT TO MODERATE RAIN AND
HIGH ELEVATION SNOW THIS AFTERNOON. AT THE TOP OF THE HOUR,
MODERATE RAIN RATES WERE STILL REPORTED OVER THE COASTAL RANGE AND
THE HIGHER TERRAIN OF EASTERN DOUGLAS COUNTY. THERE WAS AROUND A
DUSTING TO AN INCH OF SNOW AT MOST MOUNTAIN PASSES ABOVE 4000 FEET
EARLY THIS MORNING. BUT, THE SNOW LEVEL HAS RISEN TO AROUND 6500
FEET. THE CRATER LAKE VISITOR CENTER IS THE ONLY ROAD CAM STILL
SHOWING SNOW ON THE ROADWAY.
PRECIPITATION WILL TAPER OFF OVERNIGHT WITH THE FRONT DISSIPATING
OVER THE CASCADES, AND A WEAK BUT BROAD UPPER RIDGE BUILDING
INTO CALIFORNIA. SKIES ARE EXPECTED TO REMAIN MOSTLY CLOUDY TO
CLOUDY OVERNIGHT WITH PATCHY LATE NIGHT AND MORNING VALLEY FOG.
BREAKS IN THE CLOUD COVER ARE EXPECTED BY TUESDAY AFTERNOON. BUT,
THESE WILL BE SHORT-LIVED WITH A VERY WEAK WARM FRONT EXPECTED TO
MOVE NORTHEAST ACROSS CAPE MENDOCINO INTO SISKIYOU COUNTY LATE IN
THE DAY. THIS WILL BRING AN INCREASE OF MID AND HIGH LEVEL CLOUDS
INTO TUESDAY NIGHT WITH A CHANCE OF VERY LIGHT RAIN IN WESTERN
SISKIYOU COUNTY AND A SLIGHT CHANCE FOR MOST OF THE REMAINDER OF
OUR AREA THROUGH TUESDAY NIGHT.
THE GFS, NAM AND ECMWF MODELS HAVE ALL TRENDED STRONGER WITH
RIDGING WEDNESDAY INTO THURSDAY. AS A RESULT, POPS HAVE BEEN
LOWERED ON WEDNESDAY AND THE MENTION OF ANY PROBABILITY OF
PRECIPITATION REMOVED FROM WEDNESDAY NIGHT AND THURSDAY.
THE PATTERN WILL BEGIN TO CHANGE THURSDAY NIGHT WITH A TROUGH
STILL OFFSHORE BUT HEADED EAST TO NORTHEAST TOWARD NORTHERN
CALIFORNIA. BY LATE THURSDAY NIGHT...THERE IS A SLIGHT CHANCE TO
CHANCE OF RAIN ON THE WESTERN EDGES OF OUR AREA WITH A SNOW LEVEL
NEAR 6000 FEET.
LONG TERM...FRIDAY NOVEMBER 16TH THROUGH TUEDAY NOVEMBER 20TH.
AN ACTIVE AND WET PATTERN IS SHAPING UP FOR LATE IN THE WEEK
THROUGH EARLY NEXT WEEK. MODELS HAVE COME INTO BETTER AGREEMENT
FOR THIS PERIOD.
FRIDAY AND FRIDAY NIGHT, MODELS SHOW A TROUGH MOVING INLAND,
CENTERED TO THE SOUTH. THIS TROUGH IS EXPECTED TO BRING SOUTHERLY
MOISTURE INTO THE AREA. ALSO, ADDITIONAL SHORTWAVES MAY MOVE INTO THE
AREA AS THE TROUGH SHIFTS INLAND TO THE SOUTH. I HAVE KEPT CHANCE
TO LIKELY POPS OVER THE AREA FOR THIS PERIOD.
MODELS HAVE COME INTO BETTER AGREEMENT FOR THE SATURDAY THROUGH
MONDAY TIME PERIOD SHOWING A STRONG FRONTAL SYSTEM AND TROUGH MOVING
OUT OF THE GULF OF ALASKA SATURDY INTO SUNDAY WHILE A STRONG RIDGE
REMAINS INLAND EAST OF THE AREA. THE GFS IS ABOUT 6 HOURS FASTER
WITH THE FRONT PUSHING INLAND SATURDAY NIGHT WHILE THE ECMWF BRINGS
IT INLAND ON SUNDAY. GIVEN THE IMPROVED CONFIDENCE HAVE INCREASED
POPS FOR THIS PERIOD. SNOW LEVELS ARE FORECAST ABOVE 6000 FEET
SATURDAY...LOWERING BEHIND THE FRONT TO 4500 TO 5000 FEET SUNDAY
NIGHT. MODELS SHIFT THE TROUGH AXIS INLAND LATE SUNDAY WITH A
SHORTWAVE MOVING INTO THE PACNW COAST SUNDAY NIGHT INTO MONDAY.
THIS IS EXPECTED TO KEEP A HIGH CHANCE FOR RAIN AND SNOW OVER THE
AREA SATURDAY INTO MONDAY. SNOW LEVELS ARE EXPECTED TO REMAIN
ARUOND 4500 TO 5000 FEET MONDAY MORNING THEN INCREASE TO ABOVE
5000 FEET DURING THE DAY. MID LEVEL WINDS ALSO INCREASE LATE
SATURDAY INTO MONDAY AND ARE EXPECTED TO BRING PERIODS OF BREEZY
AND GUSTY WINDS, ESPECIALLY SATURDAY NIGHT INTO SUNDAY AND AGAIN
ON MONDAY. POTENTIAL AREAS AFFECTED INCLUDE THE HIGHER TERRAIN AS
WELL AS THE SHASTA VALLEY AND SUMMER LAKE AREA.
ON TUESDAY THE GFS AND ECMWF SHOW THE POTENTIAL FOR A STRONG JET
ALOFT TO DEVELOP AND NOSE INTO THE PACNW. THIS COMBINED WITH A LOW
PERSISTING IN THE GULF OF ALASKA AND SHORTWAVES AND FRONTS ROTATING
AROUND THE LOW AND MOVING INTO THE AREA, WOULD ALLOW FOR A CONTINUED
ACTIVE AND WET PATTERN. /CC
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
CA...NONE.
PZ...NONE.
$$
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
459 AM EST TUE NOV 13 2012
.SYNOPSIS...
A STRONG COLD FRONT EXTENDED FROM NEW ENGLAND INTO THE NORTHERN
GULF OF MEXICO. THIS FRONT WILL MOVE OFFSHORE BY THIS EVENING WITH
HIGH PRESSURE COVERING THE EASTERN HALF OF THE COUNTRY ON
WEDNESDAY. ANOTHER LOW WILL DEVELOP ALONG THE OLD COLD FRONT ON
FRIDAY AND SATURDAY OFF THE SOUTHEAST COAST.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 445 AM EST TUESDAY...
AT 4AM COLD FRONT EXTENDED FROM VERMONT INTO SOUTHEAST VIRGINIA.
SURFACE DEW POINTS HAD DROPPED INTO THE 30S AND 40S ACROSS THE
COUNTY WARNING AREA. DRY AIR WILL CONTINUE TO WORK INTO THE REGION
SHORT WAVE AXIS CROSSING THROUGH THE OHIO VALLEY WILL LOWER 850
TEMPERATURES OVER THE MOUNTAINS TODAY AND WILL TURN SURFACE WINDS
TO THE NORTH TONIGHT.
00Z LOCAL WRF ALONG WITH THE LATEST RUC AND SREF GUIDANCE HELD
PRECIPITATION IN THE FAR SOUTHEAST COUNTY WARNING AREA THIS
MORNING...BUT ALL MODELS SHOWED DRY WEATHER AFTER 18Z/1PM.
NARROW BAND OF STRATUS IN THE WESTERN UPSLOPE AREA FROM WEST
VIRGINIA INTO TENNESSEE IS ALSO FORECAST TO DISSIPATE BY THIS
AFTERNOON.
WITH THE WEAK COLD AIR ADVECTION AND STARTING OUT WITH EXTENSIVE
CLOUD COVER THIS MORNING HAVE USED COOLER MAV GUIDANCE AS A
STARTING POINT FOR MAXIMUM TEMPERATURES TODAY.
HIGH PRESSURE BUILDS IN TONIGHT AND PRESSURE GRADIENT WEAKENS.
WITH A CLEAR SKY AND SURFACE DEW POINTS IN THE 20S AND
30S...AGAIN TRENDED TOWARD COLDER MAV GUIDANCE FOR OVERNIGHT LOWS.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/...
AS OF 310 AM EST TUESDAY...
THE FORECAST CHALLENGE DURING THIS PORTION OF THE FORECAST IS
CENTERED AROUND THE POTENTIAL IMPACTS OF A SHORTWAVE TROUGH MOVING
NORTH ALONG THE BACK SIDE OF A COLD FRONT ALONG THE ATLANTIC COAST.
THE ECMWF FOR A FEW DAYS NOW HAS HAD THE BOLDEST SOLUTION ON
BRINGING A SWATH OF PRECIPITATION THROUGH THE SOUTHEAST PORTION OF
THE FORECAST AREA LATE WEDNESDAY NIGHT...THURSDAY...AND EVEN EARLY
THURSDAY EVENING. THE NAM HAS HAD NOTHING TO DO WITH THIS SCENARIO.
UNTIL THE 12Z...7AM MONDAY SOLUTION...THE GFS KEPT ANY ASSOCIATED
PRECIPITATION SOUTHEAST OF THE REGION. AT THIS TIME...IT TOO HINTED
AT SOME PRECIPITATION SKIRTING THE SOUTHEAST PORTION OF THE FORECAST
AREA...BUT NOT TO THE DEGREE THE ECWMF SOLUTION DID.
THE 00Z...7PM MONDAY...SOLUTIONS HAVE SHOWN THE FOLLOWING TRENDS.
THE NAM STILL HAS NOTHING TO DO WITH PRECIPITATION REACHING THE
FORECAST AREA. THE GFS IS NOT AS IMPRESSIVE WITH ITS COVERAGE OF
PRECIPITATION AND IS PRIMARILY A THURSDAY EVENT NOW. THE ECMWF IS
STILL THE BOLDEST WITH THE PRECIPITATION...BUT IT HAS SHIFTED THE
PRECIPITATION MAXIMA SOUTHEAST...WITH VERY LITTLE OF IT SKIRTING THE
FAR SOUTHEAST PART OF THE FORECAST AREA.
TO KEEP A LEVEL OF CONSISTENCY...I DO NOT WANT TO MAKE TOO DRASTIC
OF A CHANGE TO THE FORECAST. HOWEVER...GIVEN THE TRENDS...THE
FORECAST WILL REFLECT A SLIGHTLY SMALLER CONFIDENCE IS PRECIPITATION
ACROSS THE SOUTHERN AND SOUTHEASTERN PORTIONS OF THE FORECAST AREA
LATE WEDNESDAY NIGHT THROUGH THURSDAY EVENING.
OTHERWISE...LITTLE CHANGES HAVE BEEN MADE TO THE REMAINDER OF THE
FORECAST DURING THIS TIME PERIOD. WE WILL STILL HAVE A DRY AND
COLDER WEDNESDAY WITH LIMITED CLOUD COVER HAS HIGH PRESSURE MOVES
INTO THE AREA BEHIND THE COLD FRONT.
FRIDAY WILL STILL BE REPRESENTED BY A DRY FORECAST...BUT WITH THE
APPROACH OF AN UPPER TROUGH...AND THE POTENTIAL FOR SOME MOIST NE
850 MB FLOW...HAVE CONTINUE TO REMAIN ON THE HIGH SIDE FOR CLOUD
COVER.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 353 PM EST MONDAY...
ALTHOUGH NOT AS PRONOUNCED AS THEIR ENSEMBLES...THE ECMWF AND TO A
LESSER DEGREE THE GFS...ARE FURTHER WEST WITH A REX BLOCK/CLOSED
UPPER LOW THAT FIRST PINCHES APART FROM THE UPPER FLOW ALONG THE
SOUTHERN GREAT LAKES FRIDAY. THE TRACK OF THE UPPER LOW DOES GO
AROUND OUR REGION...BUT THIS STILL MEANS AT LEAST A CHANCE OF
RAIN...NUMEROUS CLOUDS AND CHILLY AIR AROUND FOR MUCH OF THE
WEEKEND. FOLLOWING ITS BIAS...THE ECMWF MAY BE TOO FAR WEST WITH THE
TRACK OF THE LOW...HOWEVER EVEN THE OPERATIONAL GFS THROWS QPF
EAST OF THE BLUE RIDGE BY SUNDAY, THIS IS AT LEAST WORTH
MENTIONABLE POPS GREATER THAN 24 PERCENT IN THE FVX/LYH/DAN
CORRIDOR. OVER THE NEXT COUPLE OF DAYS OF MODEL RUNS...ITS
PROBABLY MORE LIKELY THAT THE RAIN SHIELD WILL END UP FURTHER WEST
INTO SW VA. IN THIS WEDGY REGIME WITH ENOUGH H85 RH...BOTH THE
ECMWF MOS AND THE MEX MOS LOOK SEVERAL DEGREES TOO WARM ON HIGHS
AND SEVERAL TOO COLD ON MINS. THEREFORE REDUCED THE DIURNAL RANGE
OF TEMPS...WITH SOME SPOTS STUCK IN THE 40S FOR MAX T BOTH
SATURDAY AND SUNDAY. STRUGGLING TO FIND ENOUGH COLD AIR FOR
SNOW...PERHAPS ENOUGH UPSLOPE COOLING LATE AT NIGHT FOR SOME SNOW
TO MIX IN ACROSS THE HIGHEST ELEVATIONS OF SE WEST VA OR NW NC.
&&
.AVIATION /10Z TUESDAY THROUGH SATURDAY/...
AS OF 745 PM EST MONDAY...
FRONTAL SYSTEM AT THIS HOUR ROUGHLY ALONG A LINE FROM EKN-BLF-MKJ.
SCT-BKN -SHRA ACTIVITY NOTED GENERALLY JUST AHEAD TO ABOUT 50
MILES BEHIND THE FRONT. ACTIVITY CONTINUES TO BREAK UP AS IT
CROSSES THE MOUNTAINS. WOULD EXPECT THIS TREND TO CONTINUE...WITH
ONLY SCT ACTIVITY REACHING THE LYH-DAN AREA. EXPECT MVFR
CIGS FOR SEVERAL HOURS FOLLOWING FRONTAL PASSAGE...BUT ONLY A
LIMITED PERIOD OF MVFR VSBYS EXPECTED IN -SHRA...AFTERWARD VFR
VSBYS. FRONT SHOULD REACH BCB 02-03Z...ROA 03-04Z...AND LYH- DAN
IN THE 05-06Z TIME FRAME. WINDS MOSTLY IN THE 170-190 RANGE AT
7-10KTS WITH SOME LOW END GUSTS IN ADVANCE OF THE FRONT...BECOMING
W-NW BEHIND THE FRONT...MOSTLY 5-8KTS. SOME LOW END GUSTS AND
SUSTAINED WINDS NEAR 10KTS EXPECTED FOR 1-2 HOURS BEHIND THE
FRONTAL PASSAGE. LOW CLOUDS WILL BREAK UP LYH-DAN LATE
TONIGHT/EARLY TUE...BUT SHOULD HANG ON MUCH OF THE DAY FROM
UPSLOPE FLOW AND CAA LWB-BLF...BREAKING UP BY AFTERNOON. SOUTHERN
STREAM SYSTEM WILL START TO SPREAD MID-HIGH CLOUDS ACROSS SE
SECTIONS OF THE FORECAST AREA BY AFTERNOON.
EXPECT VFR CONDITIONS THROUGH WEDNESDAY NIGHT AS HIGH PRESSURE
RETURNS. ANOTHER WEAK LOW PRESSURE SYSTEM OFF THE SOUTHEAST COAST
MAY BRING MVFR CIGS BACK TO THE REGION BY THURSDAY MORNING.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS
SHORT TERM...DS
LONG TERM...KM
AVIATION...RAB
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1013 PM CST MON NOV 12 2012
.UPDATE...
SUBSIDENCE AND DRY AIR WORKING IN BETWEEN MAIN VORT MAX OVER ERN U.P.
OF MICHIGAN AND WEAKER VORT OVER NRN IN/SRN LOWER MI BORDER ON
WATER VAPOR IMAGERY HAVE SCOURED OUT CLOUDS OVER A PORTION OF
SOUTHERN WISCONSIN. LOOKING FOR STRATOCU DECK WRAPPING AROUND
STRONGER NORTHERN VORT MAX TO CROSS THE NORTHERN HALF TO TWO-
THIRDS OF THE CWA OVERNIGHT. EXTRAPOLATION OF BACK EDGE HAS CLOUDS
OUT OF ALL BUT THE LAKESHORE COUNTIES FROM WIND POINT NORTH AROUND
12Z TUESDAY...WITH ALL CLOUDS GONE BY 1330Z TUESDAY.
AS A RESULT OF SLOWER CLEARING...HAVE RAISED LOWS A FEW DEGREES IN
THE FAR EAST AND NORTHEAST. STILL EXPECT WESTERN AREAS TO COOL
WITH CLEARING SKIES AND DECOUPLING WINDS.
&&
.AVIATION/06Z TAFS/...
DRY AIR AND SUBSIDENCE HAVE PUSHED A WEDGE OF CLEARING ACROSS A
PORTION OF SOUTHERN WISCONSIN. LOOKING FOR VFR STRATOCU DECK
WRAPPING AROUND NORTHERN VORT MAX TO CROSS THE NORTHERN HALF TO
TWO-THIRDS OF THE CWA OVERNIGHT...COVERING ALL THE TAF SITES
EXCEPT KENW. EXTRAPOLATION OF BACK EDGE HAS IT REACHING KMSN
BETWEEN 06Z AND 07Z...KUES BETWEEN 1130Z AND 12Z...AND KMKE AROUND
1230Z. WINDS WILL DECOUPLE WITH CLEARING...BUT GUSTY NATURE OF
WINDS WILL CONTINUE WITH CLOUDS AT EASTERN SITES THOUGH SLOWLY DIMINISHING.
VFR CONDITIONS FOR THE REMAINDER OF THE PERIOD...WITH WARM-AIR
ADVECTION CLOUDS AT OR ABOVE 6K FT POSSIBLY REACHING KMSN BY 06Z
AND KMKE BY 12Z WEDNESDAY.
&&
.MARINE...
EXTENDED SMALL CRAFT ADVISORY UNTIL 12 MIDNIGHT WITH MID-LAKE BUOY
STILL REPORTING 7-FOOT WAVES AND SHORELINE OB WINDS STILL GUSTING
TO 20 KNOTS SUPPORTING 5 FOOT WAVES TOWARD OPEN WATERS. 00Z NAM
...RAP AS WELL AS HRRR SHOW WINDS DIMINISHING BETWEEN 03Z AND 06Z
ENOUGH FOR WAVES TO FALL TO 4 FEET OR LESS BY MIDNIGHT.
&&
.PREV DISCUSSION... /ISSUED 326 PM CST MON NOV 12 2012/
TONIGHT AND TUESDAY...FORECAST CONFIDENCE IS MEDIUM TO HIGH.
BROKEN AND NARROW BAND OF SNOW SHOWERS EXTENDING FROM NORTH OF
WISCONSIN DELLS TO NORTHWEST OF BOSCOBEL CURRENTLY SHIFTING EAST
SOUTHEAST TOWARD THE WESTERN COUNTIES. THIS BAND...IF IT HOLDS
TOGETHER...WOULD SHIFT EAST SOUTHEAST THROUGH PORTIONS OF THE AREA
INTO EARLY THIS EVENING.
THIS AND OTHER SCATTERED FLURRIES/LIGHT SNOW SHOWERS BEING DRIVEN BY
SHORTWAVE TROUGH WITHIN BROAD MID/UPPER TROUGH PASSING THROUGH THE
REGION. THE BAND MENTIONED EARLIER HAS PRODUCED LOW VISIBILITIES
EARLIER THIS AFTERNOON TO THE NORTHWEST...AND COULD BRING A DUSTING
OF SNOW. HOWEVER...DID NOT MENTION ANY ACCUMULATIONS...AS THIS AREA
IS BROKEN AND SKINNY AND MAY NOT HOLD TOGETHER AS IT MOVES THROUGH.
WILL HAVE TO BE WATCHED BY EVENING SHIFT. GUSTY WEST WINDS AND THE
LOW CLOUDS WILL LINGER INTO THE EVENING AS WELL.
DRIER AIRMASS MOVING INTO THE REGION SHOULD BRING GRADUALLY CLEARING
SKIES LATER THIS EVENING AND OVERNIGHT...THOUGH THERE ARE MORE
CLOUDS UPSTREAM OF THE AREA. THINKING THAT THE THIN NATURE OF THE
CLOUDS SHOULD ALLOW FOR THEM TO CLEAR OUT. CHILLY LOWS SHOULD TUMBLE
INTO THE UPPER TEENS TO LOWER 20S.
HIGH PRESSURE RIDGE TO THE SOUTH WILL BRING QUIET WEATHER FOR
TUESDAY. DRY AIRMASS WILL LEAD TO MOSTLY SUNNY SKIES...WITH COOL
TEMPERATURES CONTINUING. HIGHS IN THE MID TO UPPER 30S ARE EXPECTED
PER NAM 925MB TEMPERATURES.
WEDNESDAY THROUGH MONDAY...FORECAST CONFIDENCE IS HIGH.
WE WILL BE UNDER AN EXCEPTIONALLY STABLE PATTERN FOR A TIME OF
YEAR THAT CHARACTERISTICALLY ISN/T. BLOCKING HIGH PRESSURE WILL
RESIDE FROM NEW ENGLAND SOUTHWEST THROUGH THE GREAT LAKES. A WEAK
TROF COMES OVERHEAD ON WEDNESDAY...BUT MOISTURE AND FORCING IS
MINIMAL AND WILL KEEP IT DRY. TEMPERATURES WILL BE FAIRLY STABLE
AND NEAR NORMAL WITH HIGHS IN THE MID 40S TO AROUND 50 AND LOWS IN
THE UPPER 20S TO LOWER 30S.
AVIATION/00Z TAFS/...MVFR/VFR CEILINGS ARE EXPECTED TO LINGER
ACROSS TAF SITES THROUGH MID EVENING...AS TROUGH OF LOW PRESSURE
SHIFTS EAST THROUGH THE REGION. ONE BROKEN BAND OF MODERATE SNOW
SHOWERS WITH MVFR/IFR VISIBILITIES SHOULD REMAIN JUST NORTH OF TAF
SITES.
OTHERWISE...SCATTERED FLURRIES AND LIGHT SNOW SHOWERS ARE EXPECTED
INTO EARLY THIS EVENING. NO ACCUMULATIONS ARE EXPECTED...AND
VISIBILITIES SHOULD REMAIN VFR CATEGORY. GUSTY WEST WINDS WILL
CONTINUE INTO EARLY EVENING.
SHOULD SEE GRADUALLY CLEARING SKIES/VFR CONDITIONS LATER
TONIGHT...AS THE TROUGH OF LOW PRESSURE MOVES EAST. MOSTLY SUNNY
SKIES ARE EXPECTED TUESDAY. WINDS WILL WEAKEN LATER THIS EVENING AND
OVERNIGHT...SHIFTING SOUTHWEST TUESDAY AFTERNOON.
MARINE...SMALL CRAFT ADVISORY HAS BEEN EXTENDED UNTIL 04Z TUESDAY
ACROSS THE NEARSHORE WATERS. GUSTY WEST WINDS OF 15 TO 25 KNOTS WILL
CONTINUE UNTIL THIS TIME...AS A TIGHT PRESSURE GRADIENT LINGERS
ACROSS THE AREA. THE OFFSHORE WINDS WILL KEEP THE HIGHEST WAVES
TOWARD THE OPEN WATERS.
&&
.MKX WATCHES/WARNINGS/ADVISORIES...
WI...NONE.
LM...SMALL CRAFT ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR LMZ643>646.
&&
$$
UPDATE...REM
TONIGHT/TUESDAY AND AVIATION/MARINE...WOOD
TUESDAY NIGHT THROUGH MONDAY...DAVIS
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1052 AM EST TUE NOV 13 2012
.SYNOPSIS...
IN THE WAKE OF A COLD FRONT...A COOLER ARCTIC AIR MASS WILL
CONTINUE TO BUILD INTO THE AREA TODAY WITH A FEW LAKE EFFECT SNOW
SHOWERS POSSIBLE ACROSS THE NORTH. HIGH PRESSURE BUILDING IN FROM
THE SOUTHWEST WILL ALLOW FOR DRY WEATHER AND INCREASED SUNSHINE
FOR THE REMAINDER OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
15Z ENHANCED SHORT TERM FORECAST UPDATE HAS BEEN ISSUED TO
INCREASE CLOUD COVERAGE ACROSS THE FORECAST AREA.
THE LATEST RAP MID-LEVEL ANALYSIS INDICATES A MID-LEVEL TROUGH
ACROSS EASTERN CANADA WITH THE UPPER OHIO VALLEY AT THE BASE OF
THIS FEATURE. IN THE WAKE OF A COLD FRONT...COLD AIR ADVECTION IS
ONGOING WITH 850MB TEMPS COOLING TO -4C TO -8C ACROSS THE AREA.
850MB FLOW AT 280-290 DEGREES OFF OF LAKE ERIE ALONG WITH THE
TROUGH AXIS ALOFT HAVE PROVIDED MOSTLY CLOUDY SKIES NORTH OF THE
PITTSBURGH METRO. SOUTHWARD...LOW-LEVEL MOISTURE HAS BEEN
SUFFICIENT FOR DIURNAL CUMULUS TO DEVELOP.
TODAY...THE FORECAST AREA WILL REMAIN IN A COOL...WESTERLY 850MB
FLOW WITH A SLIGHT NORTHERLY COMPONENT ALLOWING FOR MOSTLY CLOUDY
SKIES NORTH OF PITTSBURGH AND PARTLY SUNNY SKIES SOUTHWARD. HRRR
SUPPORTS A FEW LAKE EFFECT SNOW SHOWERS ALONG THE I-80
CORRIDOR...ALTHOUGH INVERSION HEIGHTS BELOW 5000FT WILL LIMIT
SNOW SHOWERS FOR THE MOST PART. SUBSIDENCE WITH HIGH PRESSURE
BUILDING IN FROM THE MISSOURI VALLEY WILL PREVENT SHOWERS
ELSEWHERE. WITH CAA ONGOING AND CLOUD COVERAGE...TEMPS WILL
STRUGGLE TO REACH 40 ACROSS MOST OF THE AREA TODAY. HIGHS WILL
RANGE FROM LOWER 30S ACROSS THE EASTERN RIDGES TO THE LOWER 40S IN
PORTIONS OF EASTERN OHIO AND NORTH-CENTRAL WV.
TONIGHT...SURFACE RIDGING WILL BUILD INTO THE AREA...WITH A HIGH
CENTERED ACROSS LAKE ERIE BY 06Z WED. THIS BRING AN END TO
CAA...AS WAA AT 850MB RETURNS WITH RIDGING. RIDGING WILL ALLOW FOR
SKIES GRADUALLY CLEARING. RADIATIONAL COOLING TONIGHT WILL BRING LOWS
WELL INTO THE 20S WITH LIGHT WINDS.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
SURFACE HIGH PRESSURE WILL REMAIN ACROSS THE OHIO VALLEY THROUGH THE
TIME PERIOD. ALTHOUGH AN UPPER LEVEL SHORTWAVE WILL MOVE ACROSS THE
EASTERN UNITED STATES THURSDAY INTO THURSDAY NIGHT...A GENERAL LACK
OF ASSOCIATED MOISTURE SHOULD DO LITTLE MORE THAN INCREASE CLOUD
COVER. TEMPERATURES WILL SLOWLY RETURN TO NEAR NORMAL LEVELS BY THE
END OF THE WORK WEEK.
&&
.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
DRY AND SEASONABLY COOL WEATHER IS EXPECTED THROUGH THE WEEKEND
INTO EARLY NEXT WEEK. ALTHOUGH A STORM MAY DEVELOP OFF THE EAST
COAST OVER THE WEEKEND...IT APPEARS AT THIS TIME THAT THERE IS
ONLY A SLIGHT CHANCE OF THE PRECIPITATION SHIELD BRUSHING THE
RIDGES.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
AREA OF STRATOCU ACROSS THE I-80 CORRIDOR WILL REMAIN IN PLACE
THROUGH THE AFTERNOON. ELSEWHERE STRATOCU WAS BEING DEPLETED BY
DRIER AIR WORKING IN ON WESTERLY FLOW, BUT COLDER 850MB TEMPS
HELPING CU TO FILL BACK IN. OVERALL VFR CIGS WITH OCNL MVFR ACROSS
THE NORTH.
INCOMING HIGH PRESSURE SHOULD PROMOTE VFR CONDITIONS AREA WIDE
BY TONIGHT.
SURFACE WINDS WILL BE MAINLY FROM THE WEST AT NO MORE THAN 10 KTS
TODAY...THEN BECOME LIGHT TONIGHT.
.OUTLOOK.../WEDNESDAY THROUGH SATURDAY/...
VFR WILL REMAIN PREVALENT THIS PERIOD DUE TO HIGH PRESSURE
SUBSIDENCE.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
721 AM EST TUE NOV 13 2012
.SYNOPSIS...
TEMPERATURES HAVE DROPPED SHARPLY BEHIND A COLD FRONT...BUT DRY
CONDITIONS ARE EXPECTED FOR THE REST OF THE WEEK AS TEMPERATURES
SLOWLY MODERATE.
&&
.NEAR TERM /THROUGH TONIGHT/...
EARLY MORNING UPDATE TO ADJUST SKY GRIDS FOR MORE CLOUDS THIS
MORNING PITTSBURGH AND NORTH WITH CLEAR SKIES ACROSS THE SOUTH
EXCEPT FOR THE RIDGES. NO CHANGE TO FORECAST HIGHS. PREVIOUS
DISCUSSION FOLLOWS.
WINDS WILL GET A BIT OF A NORTHERLY COMPONENT TODAY...ENOUGH THAT
SOME ADDITIONAL MOISTURE SHOULD BE TAPPED FROM LAKE ERIE.
HOWEVER...WITH LOW INVERSION HEIGHTS...THINK THAT ONLY THE VERY
NORTHERN COUNTIES COULD POSSIBLY SEE AN ISOLATED SHOWER. EVEN
WITHOUT PRECIPITATION...CLOUDS ARE EXPECTED TO STICK AROUND MUCH
OF THE DAY NORTH AND EAST OF PITTSBURGH. WITH MODELS APPEARING TO
BE A BIT LOW WITH CLOUD COVER...WENT A COUPLE DEGREES BELOW
TEMPERATURE GUIDANCE FOR HIGHS...WHICH IS ALREADY 10-15 DEGREES
BELOW NORMAL.
BY TONIGHT SURFACE RIDGE WILL WORK ACROSS REGION CUTTING OFF FLOW
FROM LAKE. SKIES WILL GRADUALLY CLEAR BRINGING A COLD NIGHT WITH
LOWS WELL INTO THE 20S WITH LIGHT WINDS.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
SURFACE HIGH PRESSURE WILL REMAIN ACROSS THE OHIO VALLEY THROUGH THE
TIME PERIOD. ALTHOUGH AN UPPER LEVEL SHORTWAVE WILL MOVE ACROSS THE
EASTERN UNITED STATES THURSDAY INTO THURSDAY NIGHT...A GENERAL LACK
OF ASSOCIATED MOISTURE SHOULD DO LITTLE MORE THAN INCREASE CLOUD
COVER. TEMPERATURES WILL SLOWLY RETURN TO NEAR NORMAL LEVELS BY THE
END OF THE WORK WEEK.
&&
.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
DRY AND SEASONABLY COOL WEATHER IS EXPECTED THROUGH THE WEEKEND
INTO EARLY NEXT WEEK. ALTHOUGH A STORM MAY DEVELOP OFF THE EAST
COAST OVER THE WEEKEND...IT APPEARS AT THIS TIME THAT THERE IS
ONLY A SLIGHT CHANCE OF THE PRECIPITATION SHIELD BRUSHING THE
RIDGES.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
BLEND OF RECENT SURFACE AND SATELLITE DATA COUPLED WITH RAP AND
NAM MODEL OUTPUT SHOW POST FRONTAL STRATOCUMULUS CAN LINGER ACROSS
THE UPPER OHIO VALLEY TODAY. COVERAGE WILL VARY BETWEEN SCATTERED
AND BROKEN WITH CEILINGS MAINLY IN VFR RANGE.
THE LONE EXCEPTION MAY BE ACROSS NORTHWEST PENNSYLVANIA WHERE POST
SYSTEM COLD POOL LAKE-ENHANCED INSTABILITY CAN RENEW MVFR
STRATOCUMULUS AND ISOLATED SHOWERS IN VICINITY OF KFKL AND KDUJ
THROUGH AFTERNOON.
INCOMING HIGH PRESSURE SHOULD PROMOTE VFR CONDITIONS AREA WIDE
BY TONIGHT.
SURFACE WINDS WILL BE MAINLY FROM THE WEST AT NO MORE THAN 10 KTS
TODAY...THEN BECOME LIGHT TONIGHT.
.OUTLOOK.../WEDNESDAY THROUGH SATURDAY/...
VFR WILL REMAIN PREVALENT THIS PERIOD DUE TO HIGH PRESSURE
SUBSIDENCE.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
615 AM EST TUE NOV 13 2012
.SYNOPSIS...
TEMPERATURES HAVE DROPPED SHARPLY BEHIND A COLD FRONT...BUT DRY
CONDITIONS ARE EXPECTED FOR THE REST OF THE WEEK AS TEMPERATURES
SLOWLY MODERATE.
&&
.NEAR TERM /THROUGH TONIGHT/...
A FEW ISOLATED SHOWERS REMAIN ACROSS THE SOUTHEASTERN RIDGES...BUT
ALL PRECIPITATION SHOULD SHIFT EAST BY SUNRISE. PLENTY OF CLOUDS
REMAIN IN THE WAKE OF THE COLD FRONT...ALTHOUGH THERE IS SOME
PARTIAL CLEARING SOUTH AND WEST OF WHEELING. WINDS WILL GET A BIT OF
A NORTHERLY COMPONENT TODAY...ENOUGH THAT SOME ADDITIONAL MOISTURE
SHOULD BE TAPPED FROM LAKE ERIE. HOWEVER...WITH LOW INVERSION
HEIGHTS...THINK THAT ONLY THE VERY NORTHERN COUNTIES COULD POSSIBLY
SEE AN ISOLATED SHOWER. EVEN WITHOUT PRECIPITATION...CLOUDS ARE
EXPECTED TO STICK AROUND MUCH OF THE DAY NORTH AND EAST OF
PITTSBURGH. WITH MODELS APPEARING TO BE A BIT LOW WITH CLOUD
COVER...WENT A COUPLE DEGREES BELOW TEMPERATURE GUIDANCE FOR
HIGHS...WHICH IS ALREADY 10-15 DEGREES BELOW NORMAL.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
SURFACE HIGH PRESSURE WILL REMAIN ACROSS THE OHIO VALLEY THROUGH THE
TIME PERIOD. ALTHOUGH AN UPPER LEVEL SHORTWAVE WILL MOVE ACROSS THE
EASTERN UNITED STATES THURSDAY INTO THURSDAY NIGHT...A GENERAL LACK
OF ASSOCIATED MOISTURE SHOULD DO LITTLE MORE THAN INCREASE CLOUD
COVER. TEMPERATURES WILL SLOWLY RETURN TO NEAR NORMAL LEVELS BY THE
END OF THE WORK WEEK.
&&
.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
DRY AND SEASONABLY COOL WEATHER IS EXPECTED THROUGH THE WEEKEND
INTO EARLY NEXT WEEK. ALTHOUGH A STORM MAY DEVELOP OFF THE EAST
COAST OVER THE WEEKEND...IT APPEARS AT THIS TIME THAT THERE IS
ONLY A SLIGHT CHANCE OF THE PRECIPITATION SHIELD BRUSHING THE
RIDGES.
&&
.AVIATION /11Z TUESDAY THROUGH SATURDAY/...
BLEND OF RECENT SURFACE AND SATELLITE DATA COUPLED WITH RAP AND
NAM MODEL OUTPUT SHOW POSTFRONTAL STRATOCUMULUS CAN LINGER ACROSS
THE UPPER OHIO VALLEY TODAY. COVERAGE WILL VARY BETWEEN SCATTERED
AND BROKEN WITH CEILINGS MAINLY IN VFR RANGE.
THE LONE EXCEPTION MAY BE ACROSS NORTHWEST PENNSYLVANIA WHERE POST
SYSTEM COLD POOL LAKE-ENHANCED INSTABILITY CAN RENEW MVFR
STRATOCUMULUS AND ISOLATED SHOWERS IN VICINITY OF KFKL AND KDUJ
THROUGH AFTERNOON.
INCOMING HIGH PRESSURE SHOULD PROMOTE VFR CONDITIONS AREA WIDE
BY TONIGHT.
SURFACE WINDS WILL BE MAINLY FROM THE WEST AT NO MORE THAN 10 KTS
TODAY...THEN BECOME LIGHT TONIGHT.
.OUTLOOK.../WEDNESDAY THROUGH SATURDAY/...
VFR WILL REMAIN PREVALENT THIS PERIOD DUE TO HIGH PRESSURE
SUBSIDENCE.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
616 AM EST TUE NOV 13 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 440 AM EST TUE NOV 13 2012
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW UPR TROF OVER THE
GREAT LAKES BTWN RDG OFF THE E COAST AND A MORE ZONAL FLOW OVER WRN
NAMERICA. SINCE THE FASTEST WINDS ALF ARE ON THE E SIDE OF THE UPR
TROF...THIS IS A STRONG SIGNAL THIS TROF IS WEAKENING AND LIFTING TO
THE NE. IN FACT...12Z-24Z H5 HGT RISES IN EXCESS OF 100M AND EVEN
150M OCCURRED OVER MUCH OF THE NCENTRAL CONUS BEHIND THE UPR TROF.
FAIRLY SHARP LLVL CYC WNW FLOW OVER THE GREAT LKS UNDER THE UPR TROF
TRANSITIONS QUICKLY TO A SHARP SFC RDG AXIS OVER MN UNDER THESE HGT
RISES/SUBSIDENCE. BUT QUITE A BIT OF LLVL MSTR LINGERS PER THE 00Z
INL RAOB...SO A LO CLD OVC LINGERS ALL THE WAY W TO THE RDG AXIS.
CLOSER TO HOME...LES RESPSONSIBLE FOR UP TO 6 INCHES OF SN LINGERS
OVER THE W AS OF 06Z...WITH THE MORE PRONOUNCED REFLECTIVITIES FROM
ONTAONGAON TOWARD THE HURON MTNS WHERE SHARP LLVL CNVGC BTWN LARGER
SCALE WNW FLOW OVER THE KEWEENAW AND A MORE WSW LAND BREEZE FLOW OFF
NW WI THAT IS INFLUENCING THE AREA CLOSER TO THE WI BORDER. LATEST
TRENDS SHOW REFLECTIVITIES TENDING TO WEAKEN TO THE W...A SIGN THE
STRONG SUBIDENCE MOVING IN FM THE W MIGHT BE HAVING AN IMPACT. AS
FCST ISSUANCE APRCHS...THE RADAR REFLECTIVIES ARE DIMINISHING
RAPIDLY TO THE W. THE DOMINANT LES BAND THAT WAS OVER ERN LK SUP HAS
MOVED ONSHORE AS OF 09Z BUT HAS WEAKENED QUITE A BIT. WITH
DOWNSLOPING FLOW OF UNMODIFIED AIR...SKIES OVER THE SCENTRAL ARE
MOCLR.
MAIN FCST CONCERNS IN THE SHORT TERM ARE LES TRENDS/GOING HEADLINES
AND POSSIBLE NEED FOR AN ADVY OVER THE ERN CWA NEAR LK SUP THIS MRNG.
TODAY...AREA OF SHARP HGT RISES/DEEP LYR QVECTOR DVGC/SUBSIDENCE TO
THE W ARE FCST TO OVERSPREAD THE UPR GRT LKS AS TROF WEAKENS AND
LIFTS OUT TO THE NE...LEAVING A ZONAL FLOW ALF OVER THE AREA BY LATE
IN THE DAY. WITH ARRIVAL OF SHARP ACYC FLOW/LOWERING SUBSIDENCE
INVRN/DRYING IN THE DGZ...THINK LES WL QUICKLY DIMINISH W-E. GIVEN
THE RADAR TRENDS OVER THE W...OPTED TO CANX ADVY THAT WAS GOING TO
EXPIRE AT 12Z ANYWAY. REMOVED ANY MENTION OF -FZDZ GIVEN SFC DEWPT
DEPRESSIONS OF 5-10F EVEN THOUGH LINGERING LLVL MSTR WL BE CONFINED
BLO THE DGZ. ALTHOUGH THE BANDS COMING ASHORE OVER THE E MIGHT DROP
A COUPLE INCHES OF SN IN A FEW HRS EARLY THIS MRNG... LATEST FCST
PROFILE FM THE LOCAL WRF-ARW FOR GRAND MARAIS IN ALGER COUNTY SHOWS
INVRN BASE SINKING TO NEAR 5K FT BY 12Z WITH DRYING IN THE DGZ.
SINCE THE DOMINANT BAND HAS WEAKENED ALREADY AND THE LES MODE WL
TREND TOWARD A MULTIPLE BAND REGIME IN THE LLVL NW FLOW IN ADVANCE
OF INCOMING SFC RDG AXIS...WL ISSUE SPS TO COVER SOME LOCALLY
HEAVIER SN THIS MRNG AND NOT GO WITH AN ADVY. BY EARLY-MID AFTN...
THE PROFILE OVER THE E IS FCST TO DRY OUT COMPLETELY WITH THE
ARRIVAL OF THE SFC RDG AXIS. OTRW...LINGERING MRNG SC WL GIVE WAY TO
MOSUNNY CONDITIONS WITH THE ARRIVAL OF THE SFC RDG. IN FACT... THE
LLVL FLOW WL SHIFT TO THE SW LATER THIS AFT ONCE THE RDG AXIS SHIFTS
TO THE E.
TNGT...ALTHOUGH THE NGT WL START MOCLR...EXPECT INCRSG MID CLDS IN
THE PREVAILING SW FLOW BTWM DEPARTING SFC RDG AXIS TO THE E AND A
LO PRES TROF ASSOCIATED WITH A SHRTWV MOVING E THRU THE NRN PLAINS
IN THE ZONAL FLOW ALF. THE ISENTROPIC ASCENT IS MOST PRONOUNCED ON
THE 285-290K SFCS /H8-7/. WITH LINGERING DRY AIR BLO THE MID LVL
MOISTENING AND ABSENCE OF ANY OTHER FORCING...EXPECT NO PCPN. EXPECT
LO TEMPS TO OCCUR RELATIVELY EARLY BEFORE THE ARRIVAL OF THE MID CLD.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 440 AM EST TUE NOV 13 2012
UPPER LEVEL PATTERN BECOMING MORE ZONAL AND SPLIT ON WEDNESDAY AS
LONG TERM BEGINS. NORTHERN STREAM TROUGH OVER WESTERN CANADA MOVES
TO THE UPPER GREAT LAKES BY 12Z THURSDAY. GOOD AGREEMENT FROM NWP
ON THE POSITION/DEPTH OF THIS RELATIVELY MINOR TROUGH. WEAK 1.5PVU
ANAMOLY AHEAD OF TROUGH ALONG WITH STEADY H85-H7 WARM AIR ADVECTION
AND A BIT OF MOISTURE ADVECTION AT H85-H7 MAY BE ENOUGH TO KICK OFF
LGT PRECIP ON WEDNESDAY. AMOUNTS WILL BE LIGHT SO WILL ONLY HAVE A
MENTION OF ISOLD RAIN/SNOW SHOWERS AND/OR FLURRIES/SPRINKLES. NO BIG
DEAL AT ALL. MAIN ISSUE WILL BE A CLOUDY SKY LIMITING MAX TEMPS.
PRIMARY LEAD PV ANAMOLY AND 300MB JET STREAK COME ACROSS UPR LAKES
ON WEDNESDAY NIGHT. IF ENOUGH MOISTURE IS PRESENT...MAY BE ABLE TO
SQUEEZE OUT ISOLD SNOW SHOWERS. WORTH A MENTION...ESPECIALLY WITH
ELEVATED H7-H5 LAPSE RATES TOWARD 7 C/KM. SIMILAR FCST ON THURSDAY
WITH TROUGH AXIS OVERHEAD AND BETTER AGREEMENT ON STEEPER MID-LEVEL
LAPSE RATES. DAYTIME HEATING WILL NOT HURT CAUSE EITHER FOR POP-UP
ISOLD RAIN/SNOW SHOWERS AHEAD OF ASSOCIATED SFC TROUGH THAT MOVES
THROUGH THURSDAY EVENING. MOISTURE AVAILABLE TO THE TROUGH MAKES
IT AN OVERALL LOW CHANCE OCCURRENCE AND HAVE KEPT ANY MENTION OUT
OF THIS FCST.
TREND FROM GFS/ECMWF OVER THE LAST FEW RUNS IS TO BECOME MORE
AMPLIFIED WITH THE TROUGH AS IT PROCEEDS TO SLIDE ACROSS REST OF
THE GREAT LAKES BY FRIDAY. CAN REALLY SEE THIS ON THE GFS LOOKING AT
DPROG/DT OF H85 TEMPS OVER LK SUPERIOR AT 00Z FRIDAY. 00Z/12 RUN HAD
TEMPS OF -2C WHILE LATEST RUN HAS -7C. THOUGH RECENT RUNS OF ECMWF
ARE NOT AS COLD AS THE GFS...THE 12Z/11 RUN SHOWED A SIMILAR COLDER
SOLUTION FOR THU NIGHT AND FRIDAY AND THE LATEST RUN HAS TRENDED
COLDER AS WELL. AT THIS POINT...CANNOT COUNT OUT THE COLDER IDEA.
MAY NOT REALLY MATTER THOUGH AS THE MARGINAL MOISTURE TO BEGIN WITH
ON THURSDAY DIMINISHES FURTHER ON THURSDAY NIGHT. SPIKE OF 925MB
MOISTURE ON GFS/ECMWF INDICATE SCT CLOUDS COULD OCCUR CLOSER TO LK
SUPERIOR WITH SOME OVER-WATER INSTABILITY. ON THE FLIP SIDE...UPPER
HEIGHTS RISING SHARPLY THROUGH FRIDAY RESULTS IN SYNOPTIC SUBSIDENCE
SQUASHING INVERSION BLO H9 BY AFTN. DOES NOT APPEAR TO BE VERY GOOD
SETUP TO SEE ANYTHING BUT SCT LAKE EFFECT CLOUDS ON THURSDAY NIGHT
FOR A TIME.
IN WAKE OF TROUGH HIGH PRESSURE BUILDS RIGHT BACK IN FOR FRIDAY
THROUGH NEXT WEEKEND. EXPECT DRY WEATHER WITH TEMPS WARMING SLIGHTLY
ABOVE NORMAL FOR DAYTIME HIGHS. FORECAST SOUNDINGS OFF GFS HINT AT
LOW-LEVEL MOISTURE AND SHALLOWER INVERSION. IF THESE SIGNALS ARE
CORRECT MAY EVEN SEE SOME FOG/STRATUS FRIDAY NIGHT. IF THESE SIGNALS
ARE BOGUS THEN MAX TEMPS FROM SATURDAY THROUGH MONDAY COULD REACH
UPR 40S TO LOW-MID 50S WHICH IS 10-15F DEGREES ABOVE NORMAL.
NIGHTTIME LOWS ABOVE NORMAL TOO WITH READINGS MOSTLY ABOVE FREEZING.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING)
ISSUED AT 615 AM EST TUE NOV 13 2012
AS A HI PRES RDG MOVES IN FM MN...EXPECT LINGERING MVFR CIGS AT
IWD/CMX TO BREAK BY LATE MRNG/EARLY AFTN. DOWNSLOPE WIND COMPONENT
AT SAW WL RESULT IN VFR CONDITIONS THERE THRU THE WHOLE DAY. ALTHOUGH
MORE CLDS WL ARRIVE TNGT IN THE SW FLOW ON THE WRN FLANK OF THE HI
PRES RDG PASSING TO THE E...CIG HGTS WL BE VFR WITH DRY LLVL AIR
LINGERING.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 440 AM EST TUE NOV 13 2012
WESTERLY WINDS TO 30 KTS DIMINISH TO LESS THAN 25 KTS BY EVENING AS
PRESSURE GRADIENT GRADUALLY RELAXES DUE TO HIGH PRESSURE BUILDING
FROM THE OHIO VALLEY INTO THE GREAT LAKES. ON WEDNESDAY THE HIGH
MOVES EAST WHILE SFC TROUGH MOVES ACROSS NORTHERN ONTARIO. EXPECT
SOUTH WINDS TO INCREASE TO 30 KTS...MAINLY OVER EASTERN SECTIONS.
SMALL RISK FOR GALE GUSTS. SOUTH TO SOUTHWEST WINDS REMAIN UP TO 25
KTS THROUGH THURSDAY. SFC TROUGH COMES ACROSS THURSDAY NIGHT. WINDS
IN WAKE OF TROUGH SHIFT NORTH BY FRIDAY MORNING BUT QUICKLY DIMINISH
TO LESS THAN 20 KTS BY FRIDAY AFTERNOON WITH HIGH PRESSURE BUILDING
ACROSS REGION. EXPECT THE HIGH TO SLOWLY DRIFT TO THE NORTHEAST
THROUGH THE FIRST PART OF NEXT WEEK KEEPING WINDS LESS THAN 20 KTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...KC
MARINE...JLA
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1017 AM EST TUE NOV 13 2012
.SYNOPSIS...
AFTER A COLD START THIS MORNING, AFTERNOON HIGH TEMPERATURES WILL
AVERAGE 15 TO 20 DEGREES COLDER THAN YESTERDAY COURTESY OF A STRONG
COLD FRONT. HIGH TEMPERATURES TODAY CAN BE EXPECTED TO REMAIN IN THE
40S. DRY WEATHER AND SEASONAL TEMPERATURES ARE EXPECTED THROUGH THE
END OF THE WEEK AS HIGH PRESSURE DOMINATES THE WEATHER PATTERN.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
10 AM UPDATE...PRECIP HAS MOVED EAST OF THE REGION WITH THE
CURRENT WEAK LAKE RESPONSE NORTH OF THE FORECAST AREA ALONG THE
LAKE ONTARIO EASTERN SHORE. SATELLITE SHOWS CLOUDY TO MOSTLY
CLOUDY SKIES OVER THE ENTIRE REGION WITH 12Z RAOBS AND RAP MODEL
SOUNDINGS INDICATING A VERY SHALLOW LAYER OF MOISTURE ABOUT 50 MB
DEEP AT THE 850 MB LEVEL. THE MODEL SOUNDINGS INDICATE THIS LAYER
WILL BE VERY STUBBORN TO ERODE UNDER A STRONG SUBSIDENCE
INVERSION. ADJUSTED CLOUD GRIDS TO REFLECT THIS MORE PESSIMISTIC
THINKING OF CLOUDY TO MOSTLY CLOUDY SKIES FOR MUCH OF THE DAY
EXCEPT FOR THE FAR SE FA. DUE TO THIS INCREASED CLOUD OVER
ADJUSTED MAX TEMPS DOWN SLIGHTLY. LOW LEVEL WINDS WILL GRADUALLY
VEER TODAY WITH SCATTERED RAIN/SNOW SHOWERS FOR PRIMARILY NRN
ONEIDA COUNTY POSSIBLY DROPPING INTO THE SYR AREA LATER THIS
AFTERNOON. SNOW ACCUM OF ONLY A FEW TENTHS IN THE HIGHER TERRAIN
OF ONEIDA COUNTY.
615 AM UPDATE...
HV UPPED SNOWFALL TOTALS IN THE CATSKILLS THIS MRNG. AT THE
BINGHAMTON AIRPORT WE MEASURED 1.4 INCHES AND NOT OUT OF THE
QUESTION THAT HIGHER TERRAIN IN THE CATSKILLS MAY SEE UPWARDS OF 4
INCHES. HIGHER REFLECTIVITIES ON RADAR ALONG WITH DUAL-POL
PRODUCTS AND WEBCAMS IN THE REGION SUPPORT THIS THINKING.
HV ALSO TWEAKED HRLY TEMPS AS THEY DROPPED OFF QUICKLY THIS MRNG.
HRLY POP/WX GRIDS LOOK TO BE FAIRLY WELL IN LINE WITH REALITY SO
NO UPDATES NEEDED AT THIS TIME.
PREV DISCUSSIONS BLO...
445 AM UPDATE...
HOW QUICKLY THINGS CAN GO AWRY. JUST AS GRIDS WERE SENT, RAIN
SWITCHED OVR TO SNOW HERE AT KBGM. UPDATED GRIDS THRU 14Z TO ADD
SNOW IN AT ELEVATIONS > 1600 FT. VRY MINIMAL ACCUMS EXPECTED BUT
OVR IN THE WRN CATS MAY SEE AMNTS UPWARDS OF AN INCH BTWN NOW AND
12Z.
4 AM UPDATE... AS OF 07Z CDFNT HAS MVD THRU CWA. BULK OF THE
RAIN, AS EXPECTED, IS BHND THE FRONTAL BNDRY AS UL TROF AND ASSOC
SPEED MAX ROTATE THRU THE REGION BY 15Z. BASED ON PROGRESS OF BACK
EDGE OF MAIN AREA OF PCPN RAIN SHUD BE LOCATED OVR FAR ERN ZONES
BY 12Z AS FCST. EXPECT THIS PCPN WL SHOVE EAST OF FA BY 15Z.
WRLY FLOW BHND FNT AS WELL AS CLD TEMPS ALOFT MAY LEAD TO LK
RESPONSE FOR A TIME THIS MRNG INTO EARLY AFTN. WITH TEMPS RAPIDLY
FALLING INTO THE LOW-MID 30S BY 12Z LOCALES IN THE SRN TUG HILL
PLATEAU MAY SEE A BRIEF SNOW SHOWER THIS MRNG BFR MIXING WITH RAIN
BY 15Z. ANY LINGERING PCPN WL LKLY BE ALL RAIN BY LATE MRNG INTO THE
AFTN HRS...WITH VRY MINIMAL SNOW ACCUMS EXPECTED. THAT IS, ASSUMING
ANYTHING CAN DVLP WITH VRY LITTLE ACTIVITY EVIDENT ON KBUF RADAR AS
OF 09Z COURTESY OF LOW-LVL DRYING WORKING IN FM THE WEST.
SKIES WL GNRLY BEGIN AS MOCLDY THIS MRNG BFR CLRNG SOUTH OF THE I-88
CORRIDOR BY AFTN. SXNS WEST OF I-81 WL RMN PRTLY-MOCLDY THRU 00Z
WED. THIS WL STUNT TEMPS FM RISING TOO MUCH. ON AVG, EXPECT MAXES TO
BE SOME 20-25 DEGREES LWR THAN YDA WITH HIGHS IN THE MIDDLE-40S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
HIPRES WL BUILD IN FM THE WEST TONIGHT WITH NRLY FLOW TAKING HOLD
ACRS THE REGION. THIS WL KEEP LK CLDS IN ACRS PORTIONS OF THE AREA
AS WINDS SWING ARND FM THE NW AT 00Z TO MORE OF A NRLY FLOW BY 06Z.
LESS OF A FETCH ACRS THE LKS WL LEAD TO MOCLDY DIMINISHING TO PCLDY
OVRNGT WITH MOST AREAS EXPERIENCING SKC. GIVEN VARYING CLD CONDS
EXPECT THAT MIN TEMPS WL DIP WELL INTO THE 20S AT MOST LOCALES WITH
THE EXCEPTION OF THE LK PLAIN.
HIPRES WL SQUAT OVR THE REGION THRU THURSDAY AND BYND. MODERATING
TEMPS CAN BE EXPECTED THRU MIDWEEK. SKIES EXPECTED TO CLD UP FM THE
WEST ON THUR AFTN AS H5 L/WV TROF APPCHS FM THE WEST COURTESY OF UL
LOW OVR HUDSON BAY. HWVR, THIS WL LKLY HV LITTLE IMPACT ON TEMPS
WITH HIGHS EXPECTED IN THE MID-UPR 40S.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
1 AM UPDATE...
ONLY MINOR CHANGES. SHOULD BE A QUIET PERIOD WITH DRY WEATHER AND
STEADY TEMPERATURES AT OR SLIGHTLY BELOW SEASONAL NORMALS.
PREVIOUS DISCUSSION...
VERY LITTLE TO TALK ABOUT AGAIN THIS AFTERNOON AS MODELS
CONTINUE TO ADVERTISE A VERY QUIET PERIOD WITH HIGH PRESSURE IN
FIRM CONTROL THROUGH AT LEAST SATURDAY. NORTHERN HEMISPHERIC
500-MB TEMP/HEIGHT PROGS SHOW ZONAL FLOW PREVAILING THROUGH THE
PERIOD TO OUR NORTH ACROSS CENTRAL/NORTHERN CANADA...EFFECTIVELY
KEEPING ANY TRUE ARCTIC AIR ACROSS THE HIGHER LATITUDES. WITH THIS
BEING THE CASE...NO SIGNIFICANT COOL DOWNS ARE ANTICIPATED FROM
THIS VANTAGE POINT WITH NEAR NORMAL TEMPS EXPECTED THROUGH THE
PERIOD. ONE FEATURE THAT DOES WARRANT SOME WATCHING WILL BE A
SOUTHERN STREAM WAVE WORKING THROUGH THE SOUTHEAST/TENN RVR VLY
TOWARDS LATE WEEK. THE GFS IN PARTICULAR DOES DEVELOP CYCLOGENESIS
OFF THE SOUTHEAST COAST WITH THE MODEL THEN TAKING THE SFC LOW AND
UPPER WAVE SLOWLY UP THE EAST COAST. EXTENT OF NORTHWARD PROGRESS
REMAINS IN QUESTION THIS AFTERNOON AS BOTH GFS AND ECMWF SHOW
STRONG LOWER TROPOSPHERIC RIDGING ACROSS THE NORTHEASTERN US
THROUGH THE WEEKEND WHICH COULD SERVE TO BLOCK NORTHWARD PROGRESS
OF THE DISTURBANCE. FOR NOW HAVE ELECTED TO LEAVE ANY MENTION OF
PRECIP OUT OF THE FCST...HOWEVER IF TRENDS CONTINUE TO SHOW HIGH
PRESSURE SHIFTING TO THE NORTH...SUBSEQUENT UPDATES MAY HAVE TO
INTRODUCE POPS FOR EARLY NEXT WEEK.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
630 AM UPDATE...
MIXED PRECIP ON THE WAY OUT WITH ONLY KAVP HAVING RAIN NOW. THIS
SHOULD END BY 14Z. SOME MVFR CIGS AND MAYBE MVFR VSBYS AT KAVP
ALSO UNTIL 14Z. BEHIND THE FRONT CIGS QUICKLY RISE TO VFR AND
STAY THERE TODAY. KRME AND KBGM MAY ALSO HAVE AN HOUR OR TWO OF
MVFR RIGHT AT THE START.
DURING THE DAY TODAY CONTINUED BKN TO OVC SKIES BUT VFR. WEAK LAKE
ENHANCEMENT WITH WEST LL FLOW SHIFTING TO NW. LATE THIS AFTN TO
SUNSET SKIES WILL BECOME SCATTERED OR CLEAR AND REMAIN THAT WAY
TONIGHT. BEST CHANCE OF CLOUDS CLOSER TO THE LAKE...BUT LOW LEVEL
FLOW GOES AROUND TO NE WITH CONDITIONAL LAKE INSTABILITY. NOT
EXPECTING MANY CLOUDS TONIGHT.
W TO NW WINDS INCREASING TO 8 KTS THIS MORNING THEN CONTINUING
INTO THE AFTN. TONIGHT WINDS LIGHT TO CALM...MOSTLY FROM THE NW
TO N.
OUTLOOK...
WED THROUGH SAT...VFR WITH HIGH PRESSURE OVER THE REGION.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...PVN/RRM
NEAR TERM...PVN/RRM
SHORT TERM...PVN
LONG TERM...CMG/TAC
AVIATION...TAC
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1002 AM EST TUE NOV 13 2012
.SYNOPSIS...
A STRONG COLD FRONT WILL PUSH OFFSHORE THIS AFTERNOON...FOLLOWED BY
CHILLY CANADIAN AIR. HIGH PRESSURE WILL BUILD TO OUR NORTH THIS
WEEK...EXTENDING INTO THE CAROLINAS. A WEAK LOW PRESSURE SYSTEM WILL
DEVELOP OFFSHORE THURSDAY AND MOVE NORTHEAST. ANOTHER LOW WILL
DEVELOP OFFSHORE THIS WEEKEND WITH INCREASING CHANCES FOR RAIN.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM TUESDAY...THE SURFACE COLD FRONT EXTENDS FROM NEAR
ELIZABETHTOWN TO WHITEVILLE...ACROSS THE WESTERN PORTIONS OF HORRY
COUNTY TO NEAR KINGSTREE IN SOUTH CAROLINA. THE 11Z HRRR WAS ABOUT
ONE HOUR FAST WITH THE FRONT BUT OTHERWISE LOOKED TO BE A GOOD FIT
FOR THE SHAPE AND FORWARD SPEED OF THE BOUNDARY...PRESSING IT
OFFSHORE BY 18-19Z IN ALL AREAS.
VISIBLE SATELLITE SHOWS A NARROW ZONE OF MAINLY CLEAR SKIES JUST IN
ADVANCE OF THE FRONT WITH TEMPERATURES RISING INTO THE LOWER 70S
ALONG THE SC COAST. THESE WARMER TEMPERATURES MAY EXTEND INTO
EXTREME SE NORTH CAROLINA IN THE NEXT 1-2 HOURS BEFORE THE FRONT
SWEEPS THROUGH AND MUCH COLDER AIR BUILDS IN. HIGH TEMPERATURES HAVE
ALREADY BEEN RECORDED INLAND AND STEADY TEMPERATURES ARE ANTICIPATED
FOR THE REMAINDER OF THE DAY NEAR AND WEST OF I-95.
RADAR SHOWS ONE BATCH OF SHOWERS NEAR AND EAST OF CAPE FEAR
ASSOCIATED WITH UNSTABLE AIR ADVECTING NORTH FROM THE WESTERN EDGE
OF THE GULF STREAM. SHOWERS ACROSS THE CENTRAL CAROLINAS APPEAR TO
BE LINKED TO SMALL ELEVATED INSTABILITY IN THE 900-700 MB LAYER
ASSISTED BY SYNOPTIC-SCALE LIFT FROM THE RIGHT-ENTRANCE REGION OF A
FAVORABLY POSITIONED 300 MB JET ACROSS THE MID-ATLANTIC AND EASTERN
GREAT LAKES. THIS REGION OF ENHANCED SHOWER ACTIVITY SHOULD ADVECT
SLOWLY NORTHEASTWARD THROUGH THE AFTERNOON.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 AM TUESDAY...A LARGE AREA OF HIGH PRESSURE WILL BE CENTERED
NORTH OF NY STATE ON WEDNESDAY WITH A RIDGE AXIS/COOL AIR WEDGE
EXTENDING DOWN INTO THE CAROLINAS. THIS VERY SHALLOW COOL AIR MASS
WILL KEEP TEMPS WELL BELOW CLIMO, THE EXTENT TO WHICH WILL DEPEND ON
HOW EXTENSIVE CLOUD COVER ENDS UP BEING. AS IT IS CLOUD COVER SHOULD
BE QUITE EXTENSIVE BUT A FEW BREAKS DURING PEAK HEATING COULD REALLY
ADD SEVERAL DEGREES TO HIGH TEMPS. AS THE DAY WEARS ON HOWEVER LOW
LEVEL FLOW INCREASES JUST ATOP THE SURFACE AIRMASS IN RESPONSE TO
AN APPROACHING SHORTWAVE. THIS FEATURE SWINGS THROUGH BY THURSDAY
MORNING AND COULD TOUCH OFF WIDELY SCATTERED VERY LIGHT SHOWERS.
WEAK SUBSIDENCE THURSDAY AFTERNOON BRINGS BACK THE ORIGINAL FORECAST
ISSUE OF FIGURING OUT HOW CLOUDY THE DAY ENDS UP (STILL LIKELY
WITHIN `MOSTLY CLOUDY`) AND THE EXTENT TO WHICH THIS ENDS UP KEEPING
HIGH TEMPS BELOW CLIMO.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 3 AM TUESDAY...HIGH PRESSURE CENTERED OVER NY STATE RIDGING
INTO THE CAROLINAS WILL MERGE WITH ANOTHER HIGH MOVING IN FROM THE
WEST OVER THE WEEKEND. END RESULT WILL BE SURFACE PRESSURES
CONTINUING TO ADVECT IN FROM POINTS NORTH KEEPING TEMPS BELOW CLIMO
ESPECIALLY BY DAY. A NORTHERN BRANCH TROUGH WILL ALSO BECOME
INCREASINGLY BAGGY AND EVENTUALLY CUTOFF WEAKLY OVER GULF STATES
OVER THE WEEKEND. THE RESULTING ASCENT AHEAD OF THIS FEATURE WILL
CAUSE PRESSURES TO FALL WELL OFF THE COAST ALONG THE OLD FRONTAL
BOUNDARY. THIS WILL INITIALLY BE A VERY GRADUAL PROCESS THROUGH
SATURDAY NIGHT INTO MOST OF SUNDAY. LATER SUNDAY AS THE UPPER WAVE
GETS CLOSER TO THE COAST/FRONT BAROCLINIC INSTABILITY LEADS TO
FEEDBACK THAT STRENGTHENS THE FEATURES BOTH SURFACE AND ALOFT. HOW
MUCH RAINFALL THIS ENDS UP LEADING TO IS TOUGH TO SAY SINCE MODELS
DIVERGE ON THE STRENGTH AND THE LATITUDE OF THE SYSTEMS EVOLUTION.
THE EC, WHICH HAS BEEN QUITE ACCURATE ALONG THE EAST COAST AS OF
LATE, IS THE STRONGEST AND FURTHEST TO THE SOUTH AND WOULD IMPLY
SOME DECENT RAINS LOCALLY. THIS SOLUTION IS NOW GETTING SUPPORT FROM
THE 00Z CANADIAN MODEL. THE GFS HAS BEEN VERY CONSISTENT IN A
FLATTER AND FURTHER NORTH CYCLOGENESIS KEEPING RAINFALL CONFINED TO
THE IMMEDIATE (MAINLY NC) COAST THIS FAR SOUTH. THIS HAS BEEN THE
PREFERRED SOLUTION BUT THE AGREEMENT BETWEEN THE OTHERS IS GETTING
HARD TO IGNORE AND THE WEEKEND FORECAST WILL BE TWEAKED IN A MORE
PESSIMISTIC DIRECTION. MONDAYS FORECAST IS EVEN MORE UNCERTAIN AS
THE FASTER SOLUTIONS IMPLY DRY AND COOL AIR ADVECTION WHEREAS THE
SLOWEST POSSIBILITIES COULD STILL MEAN WRAPAROUND MOISTURE.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
AS OF 12Z...GENERALLY VFR/MVFR CIGS AND MVFR/IFR VSBYS ACROSS THE
AREA AHEAD OF AN APPROACHING COLD FRONT...WITH SHOWER ACTIVITY
APPROACHING KILM. RADAR AND SURFACE OBS INDICATE THE FRONT IS
CURRENTLY JUST WEST OF OUR CWA...AND IT SHOULD MOVE THROUGH THE
INLAND TERMS WITHIN THE NEXT HOUR OR SO. THE FRONT IS EXPECTED TO
REACH THE COASTAL SITES AROUND 14/15Z. LOWERING CIGS AND SCATTERED
LIGHT PRECIP WILL BE THE STORY FOR MUCH OF TODAY. WIDESPREAD IFR
CIGS APPEAR LIKELY THIS AFTERNOON/EVENING AS SHALLOW CAA AND A
STRONG LOW LEVEL INVERSION PROMOTE STRATUS DEVELOPMENT BEHIND THE
FRONT. LIGHT W/SW WINDS AHEAD OF THE FRONT WILL BECOME NORTHERLY 10
TO 12 KNOTS TODAY. LOW CIGS WILL PERSIST INTO THE OVERNIGHT HOURS
ALONG THE COAST...BUT THE MODEL SOUNDINGS INDICATE CIGS SHOULD LIFT
TO MVFR/VFR LEVELS TOWARDS THE END OF THE TAF PERIOD FOR THE INLAND
TERMS.
EXTENDED OUTLOOK...POST FRONTAL STRATUS POSSIBLE WED INTO THURS.
OCCASIONAL OVERRUNNING LIGHT PRECIP IS POSSIBLE THURS THROUGH SAT.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1000 AM TUESDAY...THE COLD FRONT IS CURRENTLY 40-60 MILES
INLAND FROM THE COAST AND SHOULD REACH THE BEACHES EARLY THIS
AFTERNOON...ACCOMPANIED BY A RAPID SHIFT TO NORTH WINDS AND AN
INCREASE IN SPEEDS TO AROUND 15 KNOTS. WINDS WILL STEADILY INCREASE
THIS EVENING AND SMALL CRAFT ADVISORY CONDITIONS STILL APPEAR LIKELY
OVERNIGHT. SHOWERS ARE MOST NUMEROUS NEAR AND EAST OF CAPE FEAR THIS
MORNING ALTHOUGH THERE IS ENOUGH INSTABILITY IN THE ATMOSPHERE TO
SUPPORT SHOWER DEVELOP ALMOST ANYWHERE THIS AFTERNOON INTO TONIGHT.
SEAS CURRENTLY RANGE FROM 2 FT AT THE OCEAN CREST PIER ON OAK ISLAND
TO AROUND 4 FT AT THE FRYING PAN SHOALS BUOY OFFSHORE. LITTLE CHANGE
WILL OCCUR UNTIL AFTER THE FRONT PUSHES OFFSHORE THIS AFTERNOON...AT
WHICH POINT SEAS WILL GRADUALLY BUILD TO 3-6 FT TONIGHT...HIGHEST
OFFSHORE.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 AM TUESDAY...PINCHED GRADIENT IN A POST FRONTAL
NORTHEASTERLY FLOW REGIME ON WEDNESDAY. A SMALL CRAFT ADVISORY
APPEARS LIKELY FOR MOST OF THE AREA. SOME WAVE SHADOWING MAY CALL
FOR JUST A SCEC HOWEVER OVER HORRY COUNTY WATERS. A SMALL DECREASE
IN THE WINDS IS EXPECTED EITHER THURSDAY OR THURSDAY NIGHT AS THE
FRONT SLIPS FURTHER OFFSHORE AND THIS MAY LEAD TO A BRIEF WINDOW
WHERE SCA IS NO LONGER NEEDED. AT A MINIMUM IT SEEMS LIKELY THAT
SCEC CAUTIONARY HEADLINES WILL CONTINUE.
LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 3 AM TUESDAY...HEADLINES ANTICIPATED THE ENTIRE PERIOD.
FRONTAL BOUNDARY STAYS WELL OFFSHORE WITH SURFACE HIGH PRESSURE
RIDGING DOWN INTO THE CAROLINAS FROM POINTS WELL TO THE NORTH.
COASTAL WASTERS FORECAST ZONES LIE IN THE GRADIENT BETWEEN. ON
SATURDAY GRADUAL FALLING PRESSURE ALONG THE FRONT WILL BOLSTER THE
GRADIENT AND ANY WATERS THAT HAD BEEN TEETERING NEAR THE SCEC/SCA
THRESHOLDS WILL BE PUSHED INTO ADVISORY REALM BY BOTH WIND AND SEAS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 7 PM EST
WEDNESDAY FOR AMZ250-252.
&&
$$
SYNOPSIS...TRA
NEAR TERM...TRA
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...BJR
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
403 AM MST TUE NOV 13 2012
.UPDATE...WENT AHEAD AND REMOVED ZR CHANCES THIS MORNING.
RELATIVELY WEAK LIFT IS SUPPORTING MAINLY OVERCAST SKY WITH AREAS OF
VIRGA. IF PRECIP DOES MATERIALIZE...EXPECT IT WOULD BE IN THE FORM
OF FLURRIES THIS MORNING GIVEN A DIMINISHING WARM NOSE. THIS IS
IN LINE WITH THE LATEST RAP PROFILES. ALL ELSE IN GOOD SHAPE.
&&
.AVIATION...12Z TAFS
VFR CONDITIONS WILL CONTINUE THROUGH WEDNESDAY MORNING FOR MOST
LOCATIONS. A WEAK UPPER LEVEL DISTURBANCE WILL CROSS THE NORTHERN
PLAINS TODAY...BRINGING A PERIOD OF MID LEVEL CLOUDINESS AND SOME
MVFR CIGS ACROSS THE HIGHER ELEVATIONS OF NORTHEAST WYOMING AND THE
BLACK HILLS. SOME ISOLATED LIGHT RAIN AND SNOW SHOWERS ARE EXPECTED
WITH THIS BAND OF CLOUDS...WITH ISOLATED LIGHT FREEZING RAIN SHOWERS
POSSIBLE EARLY IN THE DAY.
&&
.PREV DISCUSSION... /ISSUED 257 AM MST TUE NOV 13 2012/
DISCUSSION...
FAST DISTURBED WESTERLY FLOW WILL REMAIN IN PLACE IN THE PERIOD WITH
36 HOUR PHASE VELOCITY FAVORED IN MODEL CONSENSUS. MID LEVEL
DISTURBANCE IN THE PROCESS OF ADVECTING EAST TROUGH MT/WY/CO AS OF
09Z. THIS SYSTEM WILL QUICKLY ADVANCE EAST THROUGH THE NORTHERN
PLAINS TODAY...BRINGING ONLY A SLIGHT CHANCE FOR PRECIP TO THE AREA.
ANOTHER DISTURBANCE NOW ENTERING THE PAC NW WILL AFFECT THE AREA
WED...WITH INCREASED LIFT SUPPORTING INCREASING CLOUDS ACROSS THE
REGION. LACK OF MOISTURE WITH BOTH SYSTEMS WILL SUPPORT A MAINLY DRY
FORECAST /ESP WED/ WITH QUIET WEATHER EXPECTED IN THE PERIOD.
TODAY...FAST MOVING IMPULSE WILL CONTINUE TO SUPPORT BROAD ASCENT
OVERT THE REGION INTO THE AFTERNOON. THIS WILL SUPPORT OVERCAST
CONDITIONS FOR MOST OF THE FA...WITH CLEARING WEST TO EAST DURING THE
AFTERNOON. DISMAL MOISTURE PROFILES WITH OVERALL WEAK
WAA/FRONTOGENETICAL RESPONSE WILL SUPPORT VERY SMALL PRECIP
CHANCES...WITH MOST NUMERICAL GUIDANCE NOT SUPPORTING MUCH IN THE
WAY OF QPF. DID RETAIN LOW POPS ACROSS THE NORTHERN 2/3 ENACTING A
TIME SHIFT FOR THE AFTERNOON. IF PRECIP DOES MATERIALIZE THIS
MORNING...THERMAL PROFILES WOULD SUPPORT MAINLY SNOW WITH THE
POSSIBILITY OF SOME ZR GIVEN SFC T/S BELOW 32F AND A WARM NOSE JUST
OFF THE SFC GREATER THAN 2.5C. THIS LINES UP WITH SREF PRECIP TYPE
PROBS AND GFS DOMINANT PROGS. CLEARING EXPECTED THIS EVENING WITH
INCREASING HIGH CLOUDS W-E LATE IN THE NIGHT PER THE NEXT ADVANCING
UPPER IMPULSE. THIS IMPULSE WILL ALSO HELP TO KEEP THE BL PARTIALLY
MIXED WITH WARM PROFILES JUST OFF THE SFC...HELPING TO QUELL T FALLS
SOME.
WED/THUR...NEXT IMPULSE WILL ADV THROUGH THE NORTHERN PLAINS WITH
THE BULK OF FORCING REMAINING WELL NORTH OF THE REGION. THUS...ONLY
AN INCREASE IN CLOUDS EXPECTED. CAA ON THE BACKSIDE OF THIS SYSTEM
IS PROGGED TO BE A LITTLE MORE AGGRESSIVE WITH THE LATEST MODEL
RUNS...A CONTINUED TREND IN THE 06Z NAM. THUS...HAVE COOLED NORTHERN
AREAS DOWN WED NIGHT GIVEN FROPA AND CLEARING SKIES. HIGH
PRESSURE WILL SETTLE OVER THE REGION THUR...AS LL FLOW VEERS AROUND
TO E-SE PER THE NEXT MID LEVEL DISTURBANCE. STAUNCH PRESSURE FALLS
AND WAA THUR NIGHT WILL SUPPORT BREEZY CONDITIONS...ESP OVER NE WY.
HAVE BUMPED WINDS UP AND ADJUSTED MIN T/S PER EXPECTED TURBULENT
MIXING.
EXTENDED...WILL KEEP DRY FORECAST FOR THE EXTENDED PERIOD AS NEAR
ZONAL FLOW PERSISTS ACROSS THE REGION. WEAK DISTURBANCES IN THE FLOW
WILL LIKELY BRING SOME CLOUDINESS FROM TIME TO TIME...BUT CHANCES
FOR PCPN LOOK TO BE MINIMAL. TEMPERATURES WILL BE NEAR TO SLIGHTLY
ABOVE AVERAGE THROUGH THE PERIOD...WITH HIGHS EXPECTED TO MOSTLY BE
IN THE MID 40S TO MID 50S.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
SHORT TERM...JC
LONG TERM...15
AVIATION...15
UPDATE...JC
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
949 AM CST TUE NOV 13 2012
.DISCUSSION...EXTENDED MEASURABLE RAINFALL MORE NORTH FOR
TODAY...BUT FOR NOW KEPT THE 20 POPS. BET PART OF RAIN CELL WENT
JUST SOUTH OF KCOT WHERE THEY GOT A TRACE OF RAIN (AREAS SOUTH
PROBABLY GOT A HUNDREDTH OR TWO). DID PUT THUNDER IN FOR THE
WESTERN AREAS SINCE IT HAS BEEN A BIT OBSERVED FROM TIME TO TIME
(PRETTY COOL ALOFT). OTHERWISE...MINOR CHANGES TO FIRST/SECOND
PERIODS.
&&
.MARINE...EXTENDED SCA FOR THE NEARSHORE TIL 3 PM. RUC13 AND NAM
IS KEEPING 20-25 KNOT WINDS OVER THE NORTHEASTERN NEARSHORE
THROUGH EARLY AFTERNOON...SO HAVE EXTENDED IT. LEFT SCA FOR
OFFSHORE AS-IS. DID MENTION RAIN FOR LATE AFTERNOON/TONIGHT BUT NO
THUNDER YET. WILL TAKE A LOOK AT LATER.
&&
.PREV DISCUSSION... /ISSUED 832 AM CST TUE NOV 13 2012/
DISCUSSION...BASED ON RADAR TRENDS AND 4 KM MODEL OUTPUT FROM SPC
AND TEX-TECH...HAVE DECIDED TO MENTION MEASURABLE RAINFALL IN THE
FORECAST. RADAR IS SHOWING SOME 40-50 DBZ ECHOES IN THE BRUSH
COUNTRY AND RIO GRANDE PLAINS HEADING TOWARD COTULLA. 4KM MODELS
SHOWING SOME QPF (ISOLATED OVER 1/4 INCH...AM NOT SURE IT WILL BE
THAT MUCH). THIS RAIN/SHOWERS IS FROM AN UPPER JET STREAK AND
SUFFICIENT MOISTURE. GIVEN THE FACT THAT PWATS GET ABOVE 1 INCH
LATER THIS AFTERNOON OVER THE SOUTHEAST...WILL GO WITH SOME LIGHT
RAIN AND PUT SPRINKLES FARTHER NORTH WHERE MOISTURE IS MORE
LIMITED. HAVE EVEN SEEN AN OCCASIONAL LIGHTNING STRIKE NW OF
COTULLA BUT THINK THAT OUR AREA WILL SEE ESSENTIALLY ALL RAIN OR
SPRINKLES AND THAT ELEVATED CONVECTION TOO LIMITED TO MENTION
THUNDER AT THIS TIME (HOWEVER WILL MONITOR). PRODUCTS ARE OUT.
PREV DISCUSSION... /ISSUED 537 AM CST TUE NOV 13 2012/
DISCUSSION...UPDATED FOR 12Z AVIATION.
AVIATION...BROKEN/OVERCAST CEILINGS BETWEEN 8K AND 10K FEET ARE
ANTICIPATED THROUGH THE MAJORITY OF THE TAF CYCLE. WINDS WILL
GENERALLY BE LESS THAN 10 KNOTS...WITH A NORTHEASTERLY COMPONENT.
LOW CONFIDENCE ON LIGHT RAIN/SPRINKLES LATER TODAY WILL PRECLUDE A
MENTION IN THE TAFS ATTM. VFR FORECAST CONTINUES THE NEXT 24
HOURS.
PREV DISCUSSION... /ISSUED 438 AM CST TUE NOV 13 2012/
SHORT TERM (TODAY THROUGH WEDNESDAY)...MORNING SATELLITE IMAGERY
HAS STREAM OF MID AND LEVEL HIGH CLOUDS MOVING ACROSS SOUTH TEXAS.
TEMPERATURES CURRENTLY ARE IN THE 40S AND 50 THIS MORNING AND DO
NOT THINK TEMPS WILL FALL TOO MUCH MORE. WEAK SHORTWAVE/UPPER JET
APPROACHES THE AREA TODAY...KEEPING MOSTLY CLOUDY CONDITIONS
ACROSS SOUTH TEXAS. WITH NORTHEAST WINDS CONTINUING...TEMPS WILL
ONLY CLIMB INTO THE 60S THIS AFTERNOON IN MOST LOCATIONS. DESPITE
WEAK ISENTROPIC LIFT OVER THE AREA TODAY...THINK MEASURABLE PRECIP
MAY BE DIFFICULT TO COME BY. ALSO...06Z MAV POPS HAVE COME IN
LOWER THAN 00Z GUIDANCE AS WELL. PREFER TO CONTINUE WITH THE
MENTION OF SPRINKLES INSTEAD OF LOW END POPS. UPPER DISTURBANCE TO
PASS EAST OF THE AREA TODAY...WITH DRY NORTHWEST FLOW OVER THE
REGION ON WEDNESDAY. SOME CLOUD COVER MAY LINGER INTO WEDNESDAY...
BUT TEMPS SHOULD REBOUND A FEW DEGREES WITH UPPER 60S TO LOWER 70S
FOR HIGHS. ALSO OF NOTE...MODERATE TO STRONG NORTHEAST WINDS WILL
PERSIST TODAY OVER THE GULF WATERS. WITH SEAS STILL RUNNING 7 TO 9
FEET AND TIDE LEVEL RUNNING SLIGHTLY ABOVE PREDICTED...MINOR TIDAL
OVERFLOW MAY OCCUR AT HIGH TIDE ALONG GULF BEACHES TODAY AND HAVE
ISSUED A COASTAL FLOOD ADVISORY.
MARINE...STRONG OFFSHORE FLOW WILL PERSIST OVER THE GULF WATERS
THIS MORNING...WITH SCA CONDITIONS OVER THE NEAR AND OFFSHORE
WATERS. WINDS WILL SLOWLY DECREASE BY THIS AFTERNOON TO BELOW SCA
OVER THE NEAR SHORE WATERS...BUT SCA CONDITIONS WILL CONTINUE OVER
THE OFFSHORE WATERS THROUGH TONIGHT AS SEAS REMAIN AROUND 7 FEET.
LONG TERM (WEDNESDAY NIGHT THROUGH MONDAY)...SLIGHTLY WARMER TEMPS
CAN BE EXPECTED WED NIGHT AND THU AS THE AIRMASS BEGINS TO MODIFY.
THE SRN EXTENT OF THE SFC HIGH IS PROGD TO REMAIN DRAPED ACROSS S TX
THROUGH FRI RESULTING IN A GENERALLY LIGHT NE FLOW ACROSS THE AREA
AND A WEAK TO MOD FLOW OVER THE COASTAL WATERS. THE FLOW BEGINS TO
VEER TO THE E AND SE THRU THE WEEKEND AND THEN STRENGTHENS MON/TUE
IN RESPONSE TO A LOW PRESSURE SYSTEM MOVG ACROSS THE CENTRAL PLAINS.
THE ONSHORE FLOW WILL CONTINUE THE WARMING TREND INTO THE WEEKEND
WITH HIGHS APPROACHING THE UPPER 70S TO LOW 80S BY SUNDAY. HAVE
KNOCKED THE FCSTD TEMPS DOWN A COUPLE OF DEGREES SAT/SUN DUE TO
PERSISTENT CLOUDS AND THE WINDS BLOWING ACROSS THE COOLER WATERS.
WEAK ISENTROPIC UPGLIDE IS PROGD TO DVLP ACROSS THE RIO GRANDE
PLAINS FRI WITH DEEPER MOISTURE SURGING NWD ALONG THE RIO GRANDE.
THIS WILL COMBINE WITH AN EMBEDDED SHORT WAVE ALOFT TO BRING A
SLIGHT CHC OF -SHRA`S TO THE RIO GRANDE PLAINS. KEPT THE SLIGHT CHC
ACROSS THE SRN COASTAL BEND AS WELL DUE TO SLIGHTLY DEEPER MOISTURE
AND THE SHORT WAVE ALTHOUGH ISENTROPIC DOWNGLIDE MAY PRECLUDE RAIN
FARTHER E. SATURDAY IS PROGD TO BE A TAD DRIER...THEN ANOTHER SURGE
OF MOISTURE MOVES INTO S TX ON SUN/MON TIME FRAME ALONG WITH A
SERIES OF WEAK SHORT WAVES. THE GFS WAS PREVIOUSLY SHOWING DEEPER
MOISTURE WITH BETTER DYNAMICS ON SUNDAY BUT THE LATEST RUN HAS
PUSHED IT BACK INTO MON. DECIDED TO KEEP A BROAD BRUSHED SLIGHT CHC
FOR BOTH DAYS FOR NOW.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 65 52 71 53 73 / 20 20 10 10 10
VICTORIA 63 42 68 41 72 / 10 10 10 10 10
LAREDO 66 51 72 55 75 / 20 20 10 10 10
ALICE 65 48 71 48 75 / 20 20 10 10 10
ROCKPORT 65 52 69 57 73 / 10 20 10 10 10
COTULLA 63 45 68 49 72 / 20 10 10 10 10
KINGSVILLE 66 49 71 52 75 / 20 20 10 10 10
NAVY CORPUS 66 55 70 56 72 / 20 20 10 10 10
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...HIGH RIP CURRENT RISK THROUGH THIS EVENING FOR THE FOLLOWING
ZONES: ARANSAS...CALHOUN...KLEBERG...NUECES.
COASTAL FLOOD ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR THE
FOLLOWING ZONES: ARANSAS...CALHOUN...KLEBERG...NUECES.
GM...SMALL CRAFT ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR THE
FOLLOWING ZONES: WATERS FROM BAFFIN BAY TO PORT ARANSAS
FROM 20 TO 60 NM...WATERS FROM PORT ARANSAS TO MATAGORDA
SHIP CHANNEL FROM 20 TO 60 NM.
SMALL CRAFT ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR THE
FOLLOWING ZONES: COASTAL WATERS FROM BAFFIN BAY TO PORT
ARANSAS OUT 20 NM...COASTAL WATERS FROM PORT ARANSAS TO
MATAGORDA SHIP CHANNEL OUT 20 NM.
&&
$$
GW/86...SHORT TERM
JM/75...LONG TERM
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1030 AM EST TUE NOV 13 2012
.SYNOPSIS...
A STRONG COLD FRONT EXTENDED FROM NEW ENGLAND INTO THE NORTHERN
GULF OF MEXICO. THIS FRONT WILL MOVE OFFSHORE BY THIS EVENING WITH
HIGH PRESSURE COVERING THE EASTERN HALF OF THE COUNTRY ON
WEDNESDAY. ANOTHER LOW WILL DEVELOP ALONG THE OLD COLD FRONT ON
FRIDAY AND SATURDAY OFF THE SOUTHEAST COAST.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1015 AM EST TUESDAY...
SATELLITE IMAGERY INDICATES A VERY SHARP GRADIENT TO THE CLOUD
COVER ACROSS THE PIEDMONTS THIS MORNING...WITH MOSTLY CLEAR SKIES
WEST OF A STOKES COUNTY NC TO AMHERST COUNTY VA LINE...WHILE
CLOUDY SKIES ARE OBSERVED TO THE EAST. THESE CLOUDS...AND THE
LINGERING SHOWER ACTIVITY WITHIN...ARE MAKING STEADY PROGRESS TO
THE EAST THIS MORNING...AND EXPECT THESE REMAINING CLOUDS TO BE
OUT OF OUR AREA DURING EARLY AFTERNOON. WITH COLDER AIR
CONTINUING TO BUILD IN WITH HIGH PRESSURE TO OUR WEST...AFTERNOON
TEMPERATURES WILL BE SIGNIFICANTLY LOWER THAN YESTERDAY...AND
EXPECT HIGHS FOR TODAY TO RANGE FROM THE LOW TO MID 40S ACROSS
THE MOUNTAINS...TO THE UPPER 40S ACROSS THE PIEDMONTS.
AS OF 445 AM EST TUESDAY...
AT 4AM COLD FRONT EXTENDED FROM VERMONT INTO SOUTHEAST VIRGINIA.
SURFACE DEW POINTS HAD DROPPED INTO THE 30S AND 40S ACROSS THE
COUNTY WARNING AREA. DRY AIR WILL CONTINUE TO WORK INTO THE REGION
SHORT WAVE AXIS CROSSING THROUGH THE OHIO VALLEY WILL LOWER 850
TEMPERATURES OVER THE MOUNTAINS TODAY AND WILL TURN SURFACE WINDS
TO THE NORTH TONIGHT.
00Z LOCAL WRF ALONG WITH THE LATEST RUC AND SREF GUIDANCE HELD
PRECIPITATION IN THE FAR SOUTHEAST COUNTY WARNING AREA THIS
MORNING...BUT ALL MODELS SHOWED DRY WEATHER AFTER 18Z/1PM.
NARROW BAND OF STRATUS IN THE WESTERN UPSLOPE AREA FROM WEST
VIRGINIA INTO TENNESSEE IS ALSO FORECAST TO DISSIPATE BY THIS
AFTERNOON.
WITH THE WEAK COLD AIR ADVECTION AND STARTING OUT WITH EXTENSIVE
CLOUD COVER THIS MORNING HAVE USED COOLER MAV GUIDANCE AS A
STARTING POINT FOR MAXIMUM TEMPERATURES TODAY.
HIGH PRESSURE BUILDS IN TONIGHT AND PRESSURE GRADIENT WEAKENS.
WITH A CLEAR SKY AND SURFACE DEW POINTS IN THE 20S AND
30S...AGAIN TRENDED TOWARD COLDER MAV GUIDANCE FOR OVERNIGHT LOWS.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/...
AS OF 310 AM EST TUESDAY...
THE FORECAST CHALLENGE DURING THIS PORTION OF THE FORECAST IS
CENTERED AROUND THE POTENTIAL IMPACTS OF A SHORTWAVE TROUGH MOVING
NORTH ALONG THE BACK SIDE OF A COLD FRONT ALONG THE ATLANTIC COAST.
THE ECMWF FOR A FEW DAYS NOW HAS HAD THE BOLDEST SOLUTION ON
BRINGING A SWATH OF PRECIPITATION THROUGH THE SOUTHEAST PORTION OF
THE FORECAST AREA LATE WEDNESDAY NIGHT...THURSDAY...AND EVEN EARLY
THURSDAY EVENING. THE NAM HAS HAD NOTHING TO DO WITH THIS SCENARIO.
UNTIL THE 12Z...7AM MONDAY SOLUTION...THE GFS KEPT ANY ASSOCIATED
PRECIPITATION SOUTHEAST OF THE REGION. AT THIS TIME...IT TOO HINTED
AT SOME PRECIPITATION SKIRTING THE SOUTHEAST PORTION OF THE FORECAST
AREA...BUT NOT TO THE DEGREE THE ECWMF SOLUTION DID.
THE 00Z...7PM MONDAY...SOLUTIONS HAVE SHOWN THE FOLLOWING TRENDS.
THE NAM STILL HAS NOTHING TO DO WITH PRECIPITATION REACHING THE
FORECAST AREA. THE GFS IS NOT AS IMPRESSIVE WITH ITS COVERAGE OF
PRECIPITATION AND IS PRIMARILY A THURSDAY EVENT NOW. THE ECMWF IS
STILL THE BOLDEST WITH THE PRECIPITATION...BUT IT HAS SHIFTED THE
PRECIPITATION MAXIMA SOUTHEAST...WITH VERY LITTLE OF IT SKIRTING THE
FAR SOUTHEAST PART OF THE FORECAST AREA.
TO KEEP A LEVEL OF CONSISTENCY...I DO NOT WANT TO MAKE TOO DRASTIC
OF A CHANGE TO THE FORECAST. HOWEVER...GIVEN THE TRENDS...THE
FORECAST WILL REFLECT A SLIGHTLY SMALLER CONFIDENCE IS PRECIPITATION
ACROSS THE SOUTHERN AND SOUTHEASTERN PORTIONS OF THE FORECAST AREA
LATE WEDNESDAY NIGHT THROUGH THURSDAY EVENING.
OTHERWISE...LITTLE CHANGES HAVE BEEN MADE TO THE REMAINDER OF THE
FORECAST DURING THIS TIME PERIOD. WE WILL STILL HAVE A DRY AND
COLDER WEDNESDAY WITH LIMITED CLOUD COVER HAS HIGH PRESSURE MOVES
INTO THE AREA BEHIND THE COLD FRONT.
FRIDAY WILL STILL BE REPRESENTED BY A DRY FORECAST...BUT WITH THE
APPROACH OF AN UPPER TROUGH...AND THE POTENTIAL FOR SOME MOIST NE
850 MB FLOW...HAVE CONTINUE TO REMAIN ON THE HIGH SIDE FOR CLOUD
COVER.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 353 PM EST MONDAY...
ALTHOUGH NOT AS PRONOUNCED AS THEIR ENSEMBLES...THE ECMWF AND TO A
LESSER DEGREE THE GFS...ARE FURTHER WEST WITH A REX BLOCK/CLOSED
UPPER LOW THAT FIRST PINCHES APART FROM THE UPPER FLOW ALONG THE
SOUTHERN GREAT LAKES FRIDAY. THE TRACK OF THE UPPER LOW DOES GO
AROUND OUR REGION...BUT THIS STILL MEANS AT LEAST A CHANCE OF
RAIN...NUMEROUS CLOUDS AND CHILLY AIR AROUND FOR MUCH OF THE
WEEKEND. FOLLOWING ITS BIAS...THE ECMWF MAY BE TOO FAR WEST WITH THE
TRACK OF THE LOW...HOWEVER EVEN THE OPERATIONAL GFS THROWS QPF
EAST OF THE BLUE RIDGE BY SUNDAY, THIS IS AT LEAST WORTH
MENTIONABLE POPS GREATER THAN 24 PERCENT IN THE FVX/LYH/DAN
CORRIDOR. OVER THE NEXT COUPLE OF DAYS OF MODEL RUNS...ITS
PROBABLY MORE LIKELY THAT THE RAIN SHIELD WILL END UP FURTHER WEST
INTO SW VA. IN THIS WEDGY REGIME WITH ENOUGH H85 RH...BOTH THE
ECMWF MOS AND THE MEX MOS LOOK SEVERAL DEGREES TOO WARM ON HIGHS
AND SEVERAL TOO COLD ON MINS. THEREFORE REDUCED THE DIURNAL RANGE
OF TEMPS...WITH SOME SPOTS STUCK IN THE 40S FOR MAX T BOTH
SATURDAY AND SUNDAY. STRUGGLING TO FIND ENOUGH COLD AIR FOR
SNOW...PERHAPS ENOUGH UPSLOPE COOLING LATE AT NIGHT FOR SOME SNOW
TO MIX IN ACROSS THE HIGHEST ELEVATIONS OF SE WEST VA OR NW NC.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
AS OF 710 AM EST TUESDAY...
RADAR SHOWED BACK EDGE OF BAND OF LIGHT TO MODERATE SHOWERS THAT
WERE ASSOCIATED WITH A COLD FRONT EAST OF A LINE FROM BUENA VISTA
TO MARTINSVILLE. THE COLD FRONT AND SHOWERS WILL CONTINUE TO MOVE
EAST THIS MORNING. MODELS WERE VERY SIMILAR WITH THE TIMING OF THE
PRECIPITATION...ENDING IT AT LYH AND DAN BY 15Z/10AM. HIGH
CONFIDENCE OF MVFR CEILINGS AND VISIBILITIES WITH THE SHOWERS.
CLOUDS WILL CLEAR OUT QUICKLY BEHIND THE PRECIPITATION. EXPECT
ROA/LYH AND DAN TO BE VFR BY 17Z/NOON. NORTHWEST SURFACE AND LOW
LEVEL UPSLOPE WINDS IN THE MOUNTAINS WEAKEN TODAY AND TURN TO THE
NORTH...SO EVEN BLF AND LWB WILL BE VFR BY 18Z/1PM.
HIGH PRESSURE WILL BE OVER THE REGION TONIGHT THROUGH WEDNESDAY
NIGHT WITH VFR CONDITIONS. ANOTHER WEAK LOW PRESSURE SYSTEM OFF
THE SOUTHEAST COAST MAY BRING MVFR CIGS BACK TO THE REGION BY
THURSDAY MORNING. A MORE ORGANIZED LOW WILL DEVELOP OFF THE
SOUTHEAST COAST FRIDAY AND SATURDAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS/NF
SHORT TERM...DS
LONG TERM...KM
AVIATION...AMS/RAB
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
717 AM EST TUE NOV 13 2012
.SYNOPSIS...
A STRONG COLD FRONT EXTENDED FROM NEW ENGLAND INTO THE NORTHERN
GULF OF MEXICO. THIS FRONT WILL MOVE OFFSHORE BY THIS EVENING WITH
HIGH PRESSURE COVERING THE EASTERN HALF OF THE COUNTRY ON
WEDNESDAY. ANOTHER LOW WILL DEVELOP ALONG THE OLD COLD FRONT ON
FRIDAY AND SATURDAY OFF THE SOUTHEAST COAST.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 445 AM EST TUESDAY...
AT 4AM COLD FRONT EXTENDED FROM VERMONT INTO SOUTHEAST VIRGINIA.
SURFACE DEW POINTS HAD DROPPED INTO THE 30S AND 40S ACROSS THE
COUNTY WARNING AREA. DRY AIR WILL CONTINUE TO WORK INTO THE REGION
SHORT WAVE AXIS CROSSING THROUGH THE OHIO VALLEY WILL LOWER 850
TEMPERATURES OVER THE MOUNTAINS TODAY AND WILL TURN SURFACE WINDS
TO THE NORTH TONIGHT.
00Z LOCAL WRF ALONG WITH THE LATEST RUC AND SREF GUIDANCE HELD
PRECIPITATION IN THE FAR SOUTHEAST COUNTY WARNING AREA THIS
MORNING...BUT ALL MODELS SHOWED DRY WEATHER AFTER 18Z/1PM.
NARROW BAND OF STRATUS IN THE WESTERN UPSLOPE AREA FROM WEST
VIRGINIA INTO TENNESSEE IS ALSO FORECAST TO DISSIPATE BY THIS
AFTERNOON.
WITH THE WEAK COLD AIR ADVECTION AND STARTING OUT WITH EXTENSIVE
CLOUD COVER THIS MORNING HAVE USED COOLER MAV GUIDANCE AS A
STARTING POINT FOR MAXIMUM TEMPERATURES TODAY.
HIGH PRESSURE BUILDS IN TONIGHT AND PRESSURE GRADIENT WEAKENS.
WITH A CLEAR SKY AND SURFACE DEW POINTS IN THE 20S AND
30S...AGAIN TRENDED TOWARD COLDER MAV GUIDANCE FOR OVERNIGHT LOWS.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/...
AS OF 310 AM EST TUESDAY...
THE FORECAST CHALLENGE DURING THIS PORTION OF THE FORECAST IS
CENTERED AROUND THE POTENTIAL IMPACTS OF A SHORTWAVE TROUGH MOVING
NORTH ALONG THE BACK SIDE OF A COLD FRONT ALONG THE ATLANTIC COAST.
THE ECMWF FOR A FEW DAYS NOW HAS HAD THE BOLDEST SOLUTION ON
BRINGING A SWATH OF PRECIPITATION THROUGH THE SOUTHEAST PORTION OF
THE FORECAST AREA LATE WEDNESDAY NIGHT...THURSDAY...AND EVEN EARLY
THURSDAY EVENING. THE NAM HAS HAD NOTHING TO DO WITH THIS SCENARIO.
UNTIL THE 12Z...7AM MONDAY SOLUTION...THE GFS KEPT ANY ASSOCIATED
PRECIPITATION SOUTHEAST OF THE REGION. AT THIS TIME...IT TOO HINTED
AT SOME PRECIPITATION SKIRTING THE SOUTHEAST PORTION OF THE FORECAST
AREA...BUT NOT TO THE DEGREE THE ECWMF SOLUTION DID.
THE 00Z...7PM MONDAY...SOLUTIONS HAVE SHOWN THE FOLLOWING TRENDS.
THE NAM STILL HAS NOTHING TO DO WITH PRECIPITATION REACHING THE
FORECAST AREA. THE GFS IS NOT AS IMPRESSIVE WITH ITS COVERAGE OF
PRECIPITATION AND IS PRIMARILY A THURSDAY EVENT NOW. THE ECMWF IS
STILL THE BOLDEST WITH THE PRECIPITATION...BUT IT HAS SHIFTED THE
PRECIPITATION MAXIMA SOUTHEAST...WITH VERY LITTLE OF IT SKIRTING THE
FAR SOUTHEAST PART OF THE FORECAST AREA.
TO KEEP A LEVEL OF CONSISTENCY...I DO NOT WANT TO MAKE TOO DRASTIC
OF A CHANGE TO THE FORECAST. HOWEVER...GIVEN THE TRENDS...THE
FORECAST WILL REFLECT A SLIGHTLY SMALLER CONFIDENCE IS PRECIPITATION
ACROSS THE SOUTHERN AND SOUTHEASTERN PORTIONS OF THE FORECAST AREA
LATE WEDNESDAY NIGHT THROUGH THURSDAY EVENING.
OTHERWISE...LITTLE CHANGES HAVE BEEN MADE TO THE REMAINDER OF THE
FORECAST DURING THIS TIME PERIOD. WE WILL STILL HAVE A DRY AND
COLDER WEDNESDAY WITH LIMITED CLOUD COVER HAS HIGH PRESSURE MOVES
INTO THE AREA BEHIND THE COLD FRONT.
FRIDAY WILL STILL BE REPRESENTED BY A DRY FORECAST...BUT WITH THE
APPROACH OF AN UPPER TROUGH...AND THE POTENTIAL FOR SOME MOIST NE
850 MB FLOW...HAVE CONTINUE TO REMAIN ON THE HIGH SIDE FOR CLOUD
COVER.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 353 PM EST MONDAY...
ALTHOUGH NOT AS PRONOUNCED AS THEIR ENSEMBLES...THE ECMWF AND TO A
LESSER DEGREE THE GFS...ARE FURTHER WEST WITH A REX BLOCK/CLOSED
UPPER LOW THAT FIRST PINCHES APART FROM THE UPPER FLOW ALONG THE
SOUTHERN GREAT LAKES FRIDAY. THE TRACK OF THE UPPER LOW DOES GO
AROUND OUR REGION...BUT THIS STILL MEANS AT LEAST A CHANCE OF
RAIN...NUMEROUS CLOUDS AND CHILLY AIR AROUND FOR MUCH OF THE
WEEKEND. FOLLOWING ITS BIAS...THE ECMWF MAY BE TOO FAR WEST WITH THE
TRACK OF THE LOW...HOWEVER EVEN THE OPERATIONAL GFS THROWS QPF
EAST OF THE BLUE RIDGE BY SUNDAY, THIS IS AT LEAST WORTH
MENTIONABLE POPS GREATER THAN 24 PERCENT IN THE FVX/LYH/DAN
CORRIDOR. OVER THE NEXT COUPLE OF DAYS OF MODEL RUNS...ITS
PROBABLY MORE LIKELY THAT THE RAIN SHIELD WILL END UP FURTHER WEST
INTO SW VA. IN THIS WEDGY REGIME WITH ENOUGH H85 RH...BOTH THE
ECMWF MOS AND THE MEX MOS LOOK SEVERAL DEGREES TOO WARM ON HIGHS
AND SEVERAL TOO COLD ON MINS. THEREFORE REDUCED THE DIURNAL RANGE
OF TEMPS...WITH SOME SPOTS STUCK IN THE 40S FOR MAX T BOTH
SATURDAY AND SUNDAY. STRUGGLING TO FIND ENOUGH COLD AIR FOR
SNOW...PERHAPS ENOUGH UPSLOPE COOLING LATE AT NIGHT FOR SOME SNOW
TO MIX IN ACROSS THE HIGHEST ELEVATIONS OF SE WEST VA OR NW NC.
&&
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
AS OF 710 AM EST TUESDAY...
RADAR SHOWED BACK EDGE OF BAND OF LIGHT TO MODERATE SHOWERS THAT
WERE ASSOCIATED WITH A COLD FRONT EAST OF A LINE FROM BUENA VISTA
TO MARTINSVILLE. THE COLD FRONT AND SHOWERS WILL CONTINUE TO MOVE
EAST THIS MORNING. MODELS WERE VERY SIMILAR WITH THE TIMING OF THE
PRECIPITATION...ENDING IT AT LYH AND DAN BY 15Z/10AM. HIGH
CONFIDENCE OF MVFR CEILINGS AND VISIBILITIES WITH THE SHOWERS.
CLOUDS WILL CLEAR OUT QUICKLY BEHIND THE PRECIPITATION. EXPECT
ROA/LYH AND DAN TO BE VFR BY 17Z/NOON. NORTHWEST SURFACE AND LOW
LEVEL UPSLOPE WINDS IN THE MOUNTAINS WEAKEN TODAY AND TURN TO THE
NORTH...SO EVEN BLF AND LWB WILL BE VFR BY 18Z/1PM.
HIGH PRESSURE WILL BE OVER THE REGION TONIGHT THROUGH WEDNESDAY
NIGHT WITH VFR CONDITIONS. ANOTHER WEAK LOW PRESSURE SYSTEM OFF
THE SOUTHEAST COAST MAY BRING MVFR CIGS BACK TO THE REGION BY
THURSDAY MORNING. A MORE ORGANIZED LOW WILL DEVELOP OFF THE
SOUTHEAST COAST FRIDAY AND SATURDAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS
SHORT TERM...DS
LONG TERM...KM
AVIATION...AMS/RAB
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
934 AM MST TUE NOV 13 2012
.UPDATE...WEAK SHORTWAVE CURRENTLY MOVING ACROSS AREA. WEB CAMS
SUGGEST SOME VERY LIGHT SNOW FALLING OVER THE HIGHEST PEAKS OF
SUMMIT AND GRAND COUNTIES...BUT HARD TO VERIFY. RADAR SHOWING SOME
RETURNS ACROSS NORTHERN WELD COUNTY...BUT SURFACE OBS AND WEB CAMS
THERE NOT INDICATING ANY PRECIPITATION REACHING GROUND. WAVE TO
EXIT AREA BY THE AFTERNOON WITH CLEARING AND SUBSIDENCE IN ITS
WAKE. LATEST RUC AND NAM HOLD ONTO MEASURABLE PRECIP OVER THE
HIGHER MOUNTAINS AND NORTHEAST PLAINS THROUGH THE MORNING...THOUGH
LOOKING OVERDONE ACROSS PLAINS. CURRENT FORECAST TRENDS STILL SEEM
ON TRACK. TEMPERATURES TO BE A BIT TRICKY ACROSS WELD AND MORGAN
COUNTIES...ESPECIALLY THE LOW LYING AREAS. MAY END UP TWEAKING THE
VALUES AT THE LAST MINUTE...DEPENDING ON HOW LONG SURFACE INVERSION
PERSISTS. WINDS LOOKING RESONABLE...PERHAPS A BIT MORE WIND NEEDED
ACROSS MOUNTAINS AND FOOTHILLS TONIGHT WITH DEVELOPMENT OF
MOUNTAIN WAVE.
&&
.AVIATION...WINDS TRENDING TOWARD NORTHWEST ACROSS AREA
AIRPORTS...WITH SPEEDS LESS THAN 8 KTS. LATEST RUC INDICATING A
NORTHERLY COMPONENT BY 17Z CONTINUING THROUGH AROUND 00Z. OVERALL
CURRENT TAF TRENDS SEEM ON TRACK. ONLY CHANGE WOULD BE TO INCLUDE
A NORTHEAST COMPONENT AT DIA IN THE 20Z-22Z TIME FRAME WITH SPEEDS
BELOW 8 KTS.
&&
.PREV DISCUSSION... /ISSUED 400 AM MST TUE NOV 13 2012/
SHORT TERM...SHORTWAVE TROUGH PASSING THIS MORNING LOOKS TO BE A
FEW HOURS FASTER THAN THE MODELS...SO WE MAY SEE THE HIGH CLOUD
DECK CLEARING DENVER LATE THIS MORNING. THERE ARE SOME CLOUDS JUST
ABOVE MOUNTAINTOP BEHIND THE TROUGH AXIS...SO SOME CLOUDS WILL
LINGER WEST OF THE DIVIDE THIS MORNING AND POSSIBLY MUCH OF THE
DAY. WILL HANG ON TO THE ISOLATED LIGHT SNOW SHOWERS IN ZONE 31 AS
THESE CLOUDS SKIM OVER THE RIDGES. WEAK PRESSURE RISES BEHIND THE
TROUGH SHOULD PRODUCE A TENDENCY TOWARD WIND ROTATING THROUGH
NORTHWEST AND NORTH THIS MORNING...THOUGH SPEEDS WILL LIKELY STILL
BE PRETTY LIGHT UNDER THE INVERSION. PROBABLY JUST LIGHT THIS
AFTERNOON AS THE PRESSURE WAVE WASHES OUT. I DID WARM TEMPERATURES
IN AND NEAR THE MOUNTAINS A LITTLE IN LIGHT OF YESTERDAYS HIGHS
AND EXPECTED WARMING. PRETTY WELL LEFT THE PLAINS ALONE...HARD TO
TELL HOW MUCH IMPACT ANY NORTH WINDS WILL HAVE IN THE DENVER AREA
BUT LEFT A PATTERN OF COOLER TEMPERATURES OUT AROUND DIA AND
WARMER NEAR THE MOUNTAINS. EXPECTING SOME HIGH CLOUDS TO RETURN
TONIGHT AS ANOTHER JET STREAK PASSES NORTH OF US. WARM ADVECTION
ALOFT AND A LITTLE MORE FLOW WILL LIKELY ALSO PRODUCE A MOUNTAIN
WAVE WITH ASSOCIATED CLOUDS AND STRONGER WINDS OVER THE FRONT
RANGE. AT THIS TIME NOT EXPECTING STRONG WINDS TO PENETRATE THE
INVERSION HOWEVER...MAYBE SOME GUSTS TO 40 MPH IN THE FOOTHILLS AT
TIMES ON THE INTERFACE.
LONG TERM...MODELS KEEP THE WEST-NORTHWESTERLY FLOW ALOFT OVER THE
FORECAST AREA WEDNESDAY THROUGH THURSDAY NIGHT. THERE IS A VERY
WEAK UPPER TROUGH TO GRAZE THE NORTHEASTERN CWA AROUND 12Z
THURSDAY MORNING. THERE IS AN UPPER RIDGE AXIS OVER THE FORECAST
AREA BY 06Z THURSDAY NIGHT AND THE FLOW ALOFT BECOMES DUE
WESTERLY. FOR THE MOST PART...THE SYNOPTIC SCALE ENERGY FOR THE
CWA IS NEUTRAL THROUGH THE FOUR PERIODS. LOW LEVEL PRESSURE AND
WIND FIELDS SHOW SOUTHWESTERLY DOWNSLOPING BOUNDARY LAYER WINDS
WEDNESDAY. A WEAK COLD FRONT MOVES ACROSS THE FORECAST AREA EARLY
THURSDAY MORNING WITH SOME WEAK UPSLOPE THURSDAY. BY LATE
DAY...SOUTHEASTERLIES COVER THE PLAINS. FAIRLY STRONG SOUTHERLY
FLOW IS PROGGED THURSDAY NIGHT...ESPECAILLY OVER THE EASTERN HALF
OF THE PLAINS. FOR MOISTURE...MODELS HAVE VARIOUS AMOUNTS IN THE
MID AND UPPER LEVELS MUCH OF THE FOUR PERIODS...WITH THE GFS
SHOWING MORE THAN THE NAM. THERE IS NO MEASURABLE PRECIPITATION
OVER THE CWA ON THE QPF FIELDS MUCH OF THE TIME. THE EXCEPTION IS
BETWEEN 06Z AND 12Z WEDNESDAY NIGHT...THERE A TINY BIT IS PROGGED
OVER THE FAR NORTHWESTERN CORNER. WILL GO WITH NO POPS THIS TIME
AROUND. FOR TEMPERATURES...WEDNESDAY`S HIGHS ARE PROGGED TO BE
1.5-3.0 C WARNER THAN TODAY`S. THURSDAY HIGHS COOL OFF A TAD...1-3
C FROM WEDNESDAY`S HIGHS. FOR THE LATER DAYS...FRIDAY THROUGH
MONDAY...MODELS MAINLY KEEP FAIRLY WEAK ZONAL FLOW ALOFT FOR THE
CWA. THERE MAY BE A PIDDLY UPPER TROUGH SATURDAY NIGHT INTO
SUNDAY...OR NOT. WILL LEAVE SOME MINOR ALPINE POPS GOING SATURDAY
NIGHT INTO EARLY SUNDAY. TEMPERATURES STAY WARMER THAN NORMAL.
AVIATION...VFR CONDITIONS AND LIGHT WINDS TODAY. SOME UNCERTAINTY
ABOUT DIRECTION BUT EXPECT SEVERAL HOURS WITH A NORTHERLY
COMPONENT AROUND MIDDAY. BACK TO SOUTH/WEST DRAINAGE WINDS
THIS EVENING.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SHORT TERM...D-L
LONG TERM....RJK
AVIATION...D-L
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
316 PM EST TUE NOV 13 2012
.SYNOPSIS...
IN THE WAKE OF A COLD FRONT...A COOLER ARCTIC AIR MASS WILL
CONTINUE TO BUILD INTO THE AREA THIS EVENING WITH A FEW FLURRIES
POSSIBLE ACROSS THE NORTH. HIGH PRESSURE BUILDING IN FROM THE
SOUTHWEST WILL ALLOW FOR DRY WEATHER AND INCREASED SUNSHINE FOR
THE REMAINDER OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE LATEST RAP MID-LEVEL ANALYSIS INDICATES A MID-LEVEL TROUGH
ACROSS EASTERN CANADA WITH THE UPPER OHIO VALLEY AT THE BASE OF
THIS FEATURE. IN THE WAKE OF A COLD FRONT...COLD AIR ADVECTION IS
ONGOING WITH 850MB TEMPS COOLING TO -7C TO -10C ACROSS THE AREA.
A NORTHWESTERLY 850MB FLOW OFF OF LAKE ERIE ALONG WITH THE TROUGH
AXIS ALOFT HAVE PROVIDED MOSTLY CLOUDY SKIES ACROSS MUCH OF THE
AREA WITH A FEW FLURRIES NORTH OF PITTSBURGH.
TONIGHT...SURFACE RIDGING WILL BUILD INTO THE AREA...WITH A HIGH
CENTERED ACROSS LAKE ERIE BY 06Z WED. THIS BRING AN END TO
CAA...AS WAA AT 850MB RETURNS WITH THE RIDGE. RIDGING WILL ALLOW
FOR CLOUD COVERAGE TO BEGIN TO DECREASE FROM THE SOUTHWEST
OVERNIGHT. THERE IS STILL SOME UNCERTAINTY IN LOW TEMP FORECAST
TONIGHT AS IT WILL BE DEPENDENT ON CLEARING/RETREATING OF
STRATOCUMULUS. LOCATIONS WHERE CLEARING OCCURS WILL HAVE
OVERNIGHT TEMPS DROP OFF QUITE A BIT WITH RADIATIONAL COOLING.
WITH THIS IN MIND...LOWS RANGE FROM THE LOWER 20S IN EASTERN OHIO
AND THE RIDGES OF WV/MD TO THE MID 20S IN WESTERN PA.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
THE ORIGINAL SURFACE HIGH ACROSS THE AREA WILL SHIFT NORTHEAST OF
THE REGION ON WEDNESDAY NIGHT WITH ANOTHER HIGH FROM THE NORTHERN
PLAINS MOVING OVER THE REGION BY FRIDAY. THIS WILL ALLOW FOR A DRY
PATTERN TO CONTINUE ACROSS THE FORECAST AREA.
EARLY STRATOCUMULUS WILL DIMINISH ON WEDNESDAY WITH SKIES CLEARING
AS DRIER AND WARMER LOW-LEVEL AIR ADVECTS IN FROM THE SOUTHWEST.
THERE IS OPERATIONAL MODEL AGREEMENT THAT A SHORT WAVE TROUGH WILL
MOVE FROM THE CENTRAL PLAINS INTO THE TENNESSEE VALLEY...BRINGING
CIRRUS TO THE THE AREA FOR THURSDAY AND FRIDAY.
TEMPERATURES WILL SLOWLY MODERATE EACH DAY...WITH 850MB TEMPS
WARMING TO AROUND 2-3C ON WEDNESDAY AND LITTLE THERMAL ADVECTION
FOR THURSDAY AND FRIDAY. THERE IS LITTLE VARIATION BETWEEN
DETERMINISTIC MODELS IN TEMPS WITH HIGHS FORECAST TO BE AROUND 5
DEGREES BELOW NORMAL THROUGH THIS PERIOD.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
A QUIET EXTENDED PERIOD AS A BROAD AREA OF HIGH PRESSURE WILL
DOMINATE THE REGION. DO EXPECT AN INCREASE IN CLOUDS LATE SUNDAY
INTO TUESDAY AS AN AREA OF LOW PRESSURE ALOFT MOVES SOUTH OF THE
UPPER OHIO VALLEY...AND THE ASSOCIATED COASTAL LOW MOVES NORTH ALONG
THE EASTERN SEABOARD. NO PRECIPITATION IS EXPECTED FROM THIS SYSTEM
BASED ON CURRENT EXPECTED MOVEMENT. TEMPERATURES CLOSE TO HPC
PROGS.
&&
.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
MODEL SOUNDINGS INDICATE STRATUS WILL BE TRAPPED UNDER INVERSION
INTO THE EVENING ESPECIALLY FROM PITTSBURGH NORTH. FOR PORTIONS OF
EASTERN OHIO AND AREAS SOUTH OF PITTSBURGH STRATOCU APPEARS MORE
DIURNAL ON VIS SAT PIX AND SHOULD BE EASIER TO MIX OUT THIS EVENING.
HAVE KEPT VFR BKN CIGS IN TERMINALS FROM 00Z AT ZZV TO 04Z AT KDUJ.
SKIES SHOULD THEN BEGIN TO CLEAR AS SURFACE RIDGE CONTINUES TO BUILD
EAST. MAINLY CLEAR WEDNESDAY. WINDS WILL BE LIGHT OVERNIGHT AND THEN
NORTHEAST UNDER 10 KTS WEDNESDAY.
.OUTLOOK.../WEDNESDAY NIGHT THROUGH SUNDAY/...
VFR WILL REMAIN PREVALENT THIS PERIOD DUE TO HIGH PRESSURE
SUBSIDENCE.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
SYNOPSIS...WOODRUM
NEAR TERM...WOODRUM
SHORT TERM...WOODRUM
LONG TERM...RSMITH
AVIATION...RSMITH
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1144 AM EST TUE NOV 13 2012
.SYNOPSIS...
IN THE WAKE OF A COLD FRONT...A COOLER ARCTIC AIR MASS WILL
CONTINUE TO BUILD INTO THE AREA TODAY WITH A FEW LAKE EFFECT SNOW
SHOWERS POSSIBLE ACROSS THE NORTH. HIGH PRESSURE BUILDING IN FROM
THE SOUTHWEST WILL ALLOW FOR DRY WEATHER AND INCREASED SUNSHINE
FOR THE REMAINDER OF THE WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
A QUICK UPDATE HAS BEEN ISSUED TO INCREASE CLOUD COVERAGE TODAY
FOR LOCATIONS SOUTH OF PITTSBURGH. OTHERWISE...NO CHANGE TO THE
ONGOING FORECAST.
THE LATEST RAP MID-LEVEL ANALYSIS INDICATES A MID-LEVEL TROUGH
ACROSS EASTERN CANADA WITH THE UPPER OHIO VALLEY AT THE BASE OF
THIS FEATURE. IN THE WAKE OF A COLD FRONT...COLD AIR ADVECTION IS
ONGOING WITH 850MB TEMPS COOLING TO -4C TO -8C ACROSS THE AREA.
850MB FLOW AT 280-290 DEGREES OFF OF LAKE ERIE ALONG WITH THE
TROUGH AXIS ALOFT HAVE PROVIDED MOSTLY CLOUDY SKIES NORTH OF THE
PITTSBURGH METRO. SOUTHWARD...LOW-LEVEL MOISTURE HAS BEEN
SUFFICIENT FOR DIURNAL CUMULUS TO DEVELOP.
TODAY...THE FORECAST AREA WILL REMAIN IN A COOL...WESTERLY 850MB
FLOW WITH A SLIGHT NORTHERLY COMPONENT ALLOWING FOR CLOUDY SKIES
NORTH OF PITTSBURGH AND MOSTLY CLOUDY SKIES SOUTHWARD. HRRR
SUPPORTS A FEW LAKE EFFECT SNOW SHOWERS ALONG THE I-80
CORRIDOR...ALTHOUGH INVERSION HEIGHTS BELOW 5000FT WILL LIMIT SNOW
SHOWERS FOR THE MOST PART. SUBSIDENCE WITH HIGH PRESSURE BUILDING
IN FROM THE MISSOURI VALLEY WILL PREVENT SHOWERS ELSEWHERE. WITH
CAA ONGOING AND CLOUD COVERAGE...TEMPS WILL STRUGGLE TO REACH 40
ACROSS MOST OF THE AREA TODAY. HIGHS WILL RANGE FROM LOWER 30S
ACROSS THE EASTERN RIDGES TO THE LOWER 40S IN PORTIONS OF EASTERN
OHIO AND NORTH-CENTRAL WV.
TONIGHT...SURFACE RIDGING WILL BUILD INTO THE AREA...WITH A HIGH
CENTERED ACROSS LAKE ERIE BY 06Z WED. THIS BRING AN END TO
CAA...AS WAA AT 850MB RETURNS WITH RIDGING. RIDGING WILL ALLOW FOR
SKIES GRADUALLY CLEARING. RADIATIONAL COOLING TONIGHT WILL BRING LOWS
WELL INTO THE 20S WITH LIGHT WINDS.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY/...
SURFACE HIGH PRESSURE WILL REMAIN ACROSS THE OHIO VALLEY THROUGH THE
TIME PERIOD. ALTHOUGH AN UPPER LEVEL SHORTWAVE WILL MOVE ACROSS THE
EASTERN UNITED STATES THURSDAY INTO THURSDAY NIGHT...A GENERAL LACK
OF ASSOCIATED MOISTURE SHOULD DO LITTLE MORE THAN INCREASE CLOUD
COVER. TEMPERATURES WILL SLOWLY RETURN TO NEAR NORMAL LEVELS BY THE
END OF THE WORK WEEK.
&&
.LONG TERM /FRIDAY NIGHT THROUGH MONDAY/...
DRY AND SEASONABLY COOL WEATHER IS EXPECTED THROUGH THE WEEKEND
INTO EARLY NEXT WEEK. ALTHOUGH A STORM MAY DEVELOP OFF THE EAST
COAST OVER THE WEEKEND...IT APPEARS AT THIS TIME THAT THERE IS
ONLY A SLIGHT CHANCE OF THE PRECIPITATION SHIELD BRUSHING THE
RIDGES.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AREA OF STRATOCU ACROSS THE I-80 CORRIDOR WILL REMAIN IN PLACE
THROUGH THE AFTERNOON. ELSEWHERE STRATOCU WAS BEING DEPLETED BY
DRIER AIR WORKING IN ON WESTERLY FLOW, BUT COLDER 850MB TEMPS
HELPING CU TO FILL BACK IN. OVERALL VFR CIGS WITH OCNL MVFR ACROSS
THE NORTH.
INCOMING HIGH PRESSURE SHOULD PROMOTE VFR CONDITIONS AREA WIDE
BY TONIGHT.
SURFACE WINDS WILL BE MAINLY FROM THE WEST AT NO MORE THAN 10 KTS
TODAY...THEN BECOME LIGHT TONIGHT.
.OUTLOOK.../WEDNESDAY THROUGH SATURDAY/...
VFR WILL REMAIN PREVALENT THIS PERIOD DUE TO HIGH PRESSURE
SUBSIDENCE.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1229 PM EST TUE NOV 13 2012
.SHORT TERM...(TODAY AND TONIGHT)
ISSUED AT 440 AM EST TUE NOV 13 2012
00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW UPR TROF OVER THE
GREAT LAKES BTWN RDG OFF THE E COAST AND A MORE ZONAL FLOW OVER WRN
NAMERICA. SINCE THE FASTEST WINDS ALF ARE ON THE E SIDE OF THE UPR
TROF...THIS IS A STRONG SIGNAL THIS TROF IS WEAKENING AND LIFTING TO
THE NE. IN FACT...12Z-24Z H5 HGT RISES IN EXCESS OF 100M AND EVEN
150M OCCURRED OVER MUCH OF THE NCENTRAL CONUS BEHIND THE UPR TROF.
FAIRLY SHARP LLVL CYC WNW FLOW OVER THE GREAT LKS UNDER THE UPR TROF
TRANSITIONS QUICKLY TO A SHARP SFC RDG AXIS OVER MN UNDER THESE HGT
RISES/SUBSIDENCE. BUT QUITE A BIT OF LLVL MSTR LINGERS PER THE 00Z
INL RAOB...SO A LO CLD OVC LINGERS ALL THE WAY W TO THE RDG AXIS.
CLOSER TO HOME...LES RESPSONSIBLE FOR UP TO 6 INCHES OF SN LINGERS
OVER THE W AS OF 06Z...WITH THE MORE PRONOUNCED REFLECTIVITIES FROM
ONTAONGAON TOWARD THE HURON MTNS WHERE SHARP LLVL CNVGC BTWN LARGER
SCALE WNW FLOW OVER THE KEWEENAW AND A MORE WSW LAND BREEZE FLOW OFF
NW WI THAT IS INFLUENCING THE AREA CLOSER TO THE WI BORDER. LATEST
TRENDS SHOW REFLECTIVITIES TENDING TO WEAKEN TO THE W...A SIGN THE
STRONG SUBIDENCE MOVING IN FM THE W MIGHT BE HAVING AN IMPACT. AS
FCST ISSUANCE APRCHS...THE RADAR REFLECTIVIES ARE DIMINISHING
RAPIDLY TO THE W. THE DOMINANT LES BAND THAT WAS OVER ERN LK SUP HAS
MOVED ONSHORE AS OF 09Z BUT HAS WEAKENED QUITE A BIT. WITH
DOWNSLOPING FLOW OF UNMODIFIED AIR...SKIES OVER THE SCENTRAL ARE
MOCLR.
MAIN FCST CONCERNS IN THE SHORT TERM ARE LES TRENDS/GOING HEADLINES
AND POSSIBLE NEED FOR AN ADVY OVER THE ERN CWA NEAR LK SUP THIS MRNG.
TODAY...AREA OF SHARP HGT RISES/DEEP LYR QVECTOR DVGC/SUBSIDENCE TO
THE W ARE FCST TO OVERSPREAD THE UPR GRT LKS AS TROF WEAKENS AND
LIFTS OUT TO THE NE...LEAVING A ZONAL FLOW ALF OVER THE AREA BY LATE
IN THE DAY. WITH ARRIVAL OF SHARP ACYC FLOW/LOWERING SUBSIDENCE
INVRN/DRYING IN THE DGZ...THINK LES WL QUICKLY DIMINISH W-E. GIVEN
THE RADAR TRENDS OVER THE W...OPTED TO CANX ADVY THAT WAS GOING TO
EXPIRE AT 12Z ANYWAY. REMOVED ANY MENTION OF -FZDZ GIVEN SFC DEWPT
DEPRESSIONS OF 5-10F EVEN THOUGH LINGERING LLVL MSTR WL BE CONFINED
BLO THE DGZ. ALTHOUGH THE BANDS COMING ASHORE OVER THE E MIGHT DROP
A COUPLE INCHES OF SN IN A FEW HRS EARLY THIS MRNG... LATEST FCST
PROFILE FM THE LOCAL WRF-ARW FOR GRAND MARAIS IN ALGER COUNTY SHOWS
INVRN BASE SINKING TO NEAR 5K FT BY 12Z WITH DRYING IN THE DGZ.
SINCE THE DOMINANT BAND HAS WEAKENED ALREADY AND THE LES MODE WL
TREND TOWARD A MULTIPLE BAND REGIME IN THE LLVL NW FLOW IN ADVANCE
OF INCOMING SFC RDG AXIS...WL ISSUE SPS TO COVER SOME LOCALLY
HEAVIER SN THIS MRNG AND NOT GO WITH AN ADVY. BY EARLY-MID AFTN...
THE PROFILE OVER THE E IS FCST TO DRY OUT COMPLETELY WITH THE
ARRIVAL OF THE SFC RDG AXIS. OTRW...LINGERING MRNG SC WL GIVE WAY TO
MOSUNNY CONDITIONS WITH THE ARRIVAL OF THE SFC RDG. IN FACT... THE
LLVL FLOW WL SHIFT TO THE SW LATER THIS AFT ONCE THE RDG AXIS SHIFTS
TO THE E.
TNGT...ALTHOUGH THE NGT WL START MOCLR...EXPECT INCRSG MID CLDS IN
THE PREVAILING SW FLOW BTWM DEPARTING SFC RDG AXIS TO THE E AND A
LO PRES TROF ASSOCIATED WITH A SHRTWV MOVING E THRU THE NRN PLAINS
IN THE ZONAL FLOW ALF. THE ISENTROPIC ASCENT IS MOST PRONOUNCED ON
THE 285-290K SFCS /H8-7/. WITH LINGERING DRY AIR BLO THE MID LVL
MOISTENING AND ABSENCE OF ANY OTHER FORCING...EXPECT NO PCPN. EXPECT
LO TEMPS TO OCCUR RELATIVELY EARLY BEFORE THE ARRIVAL OF THE MID CLD.
.LONG TERM...(WEDNESDAY THROUGH MONDAY)
ISSUED AT 440 AM EST TUE NOV 13 2012
UPPER LEVEL PATTERN BECOMING MORE ZONAL AND SPLIT ON WEDNESDAY AS
LONG TERM BEGINS. NORTHERN STREAM TROUGH OVER WESTERN CANADA MOVES
TO THE UPPER GREAT LAKES BY 12Z THURSDAY. GOOD AGREEMENT FROM NWP
ON THE POSITION/DEPTH OF THIS RELATIVELY MINOR TROUGH. WEAK 1.5PVU
ANAMOLY AHEAD OF TROUGH ALONG WITH STEADY H85-H7 WARM AIR ADVECTION
AND A BIT OF MOISTURE ADVECTION AT H85-H7 MAY BE ENOUGH TO KICK OFF
LGT PRECIP ON WEDNESDAY. AMOUNTS WILL BE LIGHT SO WILL ONLY HAVE A
MENTION OF ISOLD RAIN/SNOW SHOWERS AND/OR FLURRIES/SPRINKLES. NO BIG
DEAL AT ALL. MAIN ISSUE WILL BE A CLOUDY SKY LIMITING MAX TEMPS.
PRIMARY LEAD PV ANAMOLY AND 300MB JET STREAK COME ACROSS UPR LAKES
ON WEDNESDAY NIGHT. IF ENOUGH MOISTURE IS PRESENT...MAY BE ABLE TO
SQUEEZE OUT ISOLD SNOW SHOWERS. WORTH A MENTION...ESPECIALLY WITH
ELEVATED H7-H5 LAPSE RATES TOWARD 7 C/KM. SIMILAR FCST ON THURSDAY
WITH TROUGH AXIS OVERHEAD AND BETTER AGREEMENT ON STEEPER MID-LEVEL
LAPSE RATES. DAYTIME HEATING WILL NOT HURT CAUSE EITHER FOR POP-UP
ISOLD RAIN/SNOW SHOWERS AHEAD OF ASSOCIATED SFC TROUGH THAT MOVES
THROUGH THURSDAY EVENING. MOISTURE AVAILABLE TO THE TROUGH MAKES
IT AN OVERALL LOW CHANCE OCCURRENCE AND HAVE KEPT ANY MENTION OUT
OF THIS FCST.
TREND FROM GFS/ECMWF OVER THE LAST FEW RUNS IS TO BECOME MORE
AMPLIFIED WITH THE TROUGH AS IT PROCEEDS TO SLIDE ACROSS REST OF
THE GREAT LAKES BY FRIDAY. CAN REALLY SEE THIS ON THE GFS LOOKING AT
DPROG/DT OF H85 TEMPS OVER LK SUPERIOR AT 00Z FRIDAY. 00Z/12 RUN HAD
TEMPS OF -2C WHILE LATEST RUN HAS -7C. THOUGH RECENT RUNS OF ECMWF
ARE NOT AS COLD AS THE GFS...THE 12Z/11 RUN SHOWED A SIMILAR COLDER
SOLUTION FOR THU NIGHT AND FRIDAY AND THE LATEST RUN HAS TRENDED
COLDER AS WELL. AT THIS POINT...CANNOT COUNT OUT THE COLDER IDEA.
MAY NOT REALLY MATTER THOUGH AS THE MARGINAL MOISTURE TO BEGIN WITH
ON THURSDAY DIMINISHES FURTHER ON THURSDAY NIGHT. SPIKE OF 925MB
MOISTURE ON GFS/ECMWF INDICATE SCT CLOUDS COULD OCCUR CLOSER TO LK
SUPERIOR WITH SOME OVER-WATER INSTABILITY. ON THE FLIP SIDE...UPPER
HEIGHTS RISING SHARPLY THROUGH FRIDAY RESULTS IN SYNOPTIC SUBSIDENCE
SQUASHING INVERSION BLO H9 BY AFTN. DOES NOT APPEAR TO BE VERY GOOD
SETUP TO SEE ANYTHING BUT SCT LAKE EFFECT CLOUDS ON THURSDAY NIGHT
FOR A TIME.
IN WAKE OF TROUGH HIGH PRESSURE BUILDS RIGHT BACK IN FOR FRIDAY
THROUGH NEXT WEEKEND. EXPECT DRY WEATHER WITH TEMPS WARMING SLIGHTLY
ABOVE NORMAL FOR DAYTIME HIGHS. FORECAST SOUNDINGS OFF GFS HINT AT
LOW-LEVEL MOISTURE AND SHALLOWER INVERSION. IF THESE SIGNALS ARE
CORRECT MAY EVEN SEE SOME FOG/STRATUS FRIDAY NIGHT. IF THESE SIGNALS
ARE BOGUS THEN MAX TEMPS FROM SATURDAY THROUGH MONDAY COULD REACH
UPR 40S TO LOW-MID 50S WHICH IS 10-15F DEGREES ABOVE NORMAL.
NIGHTTIME LOWS ABOVE NORMAL TOO WITH READINGS MOSTLY ABOVE FREEZING.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON)
ISSUED AT 1228 PM EST TUE NOV 13 2012
HIGH PRESSURE BUILDING INTO THE AREA FROM THE SOUTH WILL CONTINUE TO
HELP ERODE THE CLOUD LAYER THAT HAS REMAINED IN PLACE THROUGH MUCH
OF THE MORNING HOURS. ALL TAF SITES SHOULD REMAIN VFR THROUGH THE
TAF PERIOD. IWD AND SAW HAVE CLEARED OUT AS OF 17Z AND SHOULD REMAIN
THAT WAY THROUGH THE AFTERNOON HOURS. CMX WILL BEGIN TO CLEAR OUT BY
18Z AND REMAIN CLEAR THROUGH THE AFTERNOON HOURS AS WELL. INCREASING
MOISTURE IN THE MID LEVEL WILL HELP TO INCREASE CLOUD COVER AT ALL
TAF SITES TONIGHT THROUGH THE REMAINDER OF THE TAF PERIOD. THERE IS
A SMALL CHANCE THAT -SHRA OR-SHSN COULD OCCUR...BUT LOW LEVEL DRYING
COULD KEEP THIS FROM OCCURRING. AT THIS POINT HAVE INCREASED CLOUDS
BUT KEPT CONDITIONS DRY. VISIBILITIES SHOULD REMAIN VFR. WIND SHOULD
REMAIN LIGHT AND SOUTHERLY AT EACH TAF SITE.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 440 AM EST TUE NOV 13 2012
WESTERLY WINDS TO 30 KTS DIMINISH TO LESS THAN 25 KTS BY EVENING AS
PRESSURE GRADIENT GRADUALLY RELAXES DUE TO HIGH PRESSURE BUILDING
FROM THE OHIO VALLEY INTO THE GREAT LAKES. ON WEDNESDAY THE HIGH
MOVES EAST WHILE SFC TROUGH MOVES ACROSS NORTHERN ONTARIO. EXPECT
SOUTH WINDS TO INCREASE TO 30 KTS...MAINLY OVER EASTERN SECTIONS.
SMALL RISK FOR GALE GUSTS. SOUTH TO SOUTHWEST WINDS REMAIN UP TO 25
KTS THROUGH THURSDAY. SFC TROUGH COMES ACROSS THURSDAY NIGHT. WINDS
IN WAKE OF TROUGH SHIFT NORTH BY FRIDAY MORNING BUT QUICKLY DIMINISH
TO LESS THAN 20 KTS BY FRIDAY AFTERNOON WITH HIGH PRESSURE BUILDING
ACROSS REGION. EXPECT THE HIGH TO SLOWLY DRIFT TO THE NORTHEAST
THROUGH THE FIRST PART OF NEXT WEEK KEEPING WINDS LESS THAN 20 KTS.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
NONE.
LAKE SUPERIOR...
NONE.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...KC
LONG TERM...JLA
AVIATION...KEC
MARINE...JLA
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
248 PM EST TUE NOV 13 2012
.SYNOPSIS...
CLOUDS WILL GRADUALLY DECREASE TONIGHT INTO WEDNESDAY WITH
HIGH PRESSURE TAKING OVER. DRY WEATHER AND SEASONAL TEMPERATURES ARE
EXPECTED ALL THE WAY THROUGH AT LEAST SUNDAY AS HIGH PRESSURE
DOMINATES THE WEATHER PATTERN.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
12 PM UPDATE...LATEST SAT PICS CONTINUE TO SHOW WIDESPREAD STRATO
CU ACROSS THE CWA WITH A FEW BREAKS IN THE WESTERN MOHAWK VALLEY
AND WYOMING VALLEY. OTHER THAN ADJUSTING MAX TEMPS DOWN A BIT MORE
FORECAST IN GOOD SHAPE.
10 AM UPDATE...PRECIP HAS MOVED EAST OF THE REGION WITH THE
CURRENT WEAK LAKE RESPONSE NORTH OF THE FORECAST AREA ALONG THE
LAKE ONTARIO EASTERN SHORE. SATELLITE SHOWS CLOUDY TO MOSTLY
CLOUDY SKIES OVER THE ENTIRE REGION WITH 12Z RAOBS AND RAP MODEL
SOUNDINGS INDICATING A VERY SHALLOW LAYER OF MOISTURE ABOUT 50 MB
DEEP AT THE 850 MB LEVEL. THE MODEL SOUNDINGS INDICATE THIS LAYER
WILL BE VERY STUBBORN TO ERODE UNDER A STRONG SUBSIDENCE
INVERSION. ADJUSTED CLOUD GRIDS TO REFLECT THIS MORE PESSIMISTIC
THINKING OF CLOUDY TO MOSTLY CLOUDY SKIES FOR MUCH OF THE DAY
EXCEPT FOR THE FAR SE FA. DUE TO THIS INCREASED CLOUD COVER
ADJUSTED MAX TEMPS DOWN SLIGHTLY. LOW LEVEL WINDS WILL GRADUALLY
VEER TODAY WITH SCATTERED RAIN/SNOW SHOWERS FOR PRIMARILY NRN
ONEIDA COUNTY POSSIBLY DROPPING INTO THE SYR AREA LATER THIS
AFTERNOON. SNOW ACCUM OF ONLY A FEW TENTHS IN THE HIGHER TERRAIN
OF ONEIDA COUNTY.
615 AM UPDATE...
HV UPPED SNOWFALL TOTALS IN THE CATSKILLS THIS MRNG. AT THE
BINGHAMTON AIRPORT WE MEASURED 1.4 INCHES AND NOT OUT OF THE
QUESTION THAT HIGHER TERRAIN IN THE CATSKILLS MAY SEE UPWARDS OF 4
INCHES. HIGHER REFLECTIVITIES ON RADAR ALONG WITH DUAL-POL
PRODUCTS AND WEBCAMS IN THE REGION SUPPORT THIS THINKING.
HV ALSO TWEAKED HRLY TEMPS AS THEY DROPPED OFF QUICKLY THIS MRNG.
HRLY POP/WX GRIDS LOOK TO BE FAIRLY WELL IN LINE WITH REALITY SO
NO UPDATES NEEDED AT THIS TIME.
PREV DISCUSSIONS BLO...
445 AM UPDATE...
HOW QUICKLY THINGS CAN GO AWRY. JUST AS GRIDS WERE SENT, RAIN
SWITCHED OVR TO SNOW HERE AT KBGM. UPDATED GRIDS THRU 14Z TO ADD
SNOW IN AT ELEVATIONS > 1600 FT. VRY MINIMAL ACCUMS EXPECTED BUT
OVR IN THE WRN CATS MAY SEE AMNTS UPWARDS OF AN INCH BTWN NOW AND
12Z.
4 AM UPDATE... AS OF 07Z CDFNT HAS MVD THRU CWA. BULK OF THE
RAIN, AS EXPECTED, IS BHND THE FRONTAL BNDRY AS UL TROF AND ASSOC
SPEED MAX ROTATE THRU THE REGION BY 15Z. BASED ON PROGRESS OF BACK
EDGE OF MAIN AREA OF PCPN RAIN SHUD BE LOCATED OVR FAR ERN ZONES
BY 12Z AS FCST. EXPECT THIS PCPN WL SHOVE EAST OF FA BY 15Z.
WRLY FLOW BHND FNT AS WELL AS CLD TEMPS ALOFT MAY LEAD TO LK
RESPONSE FOR A TIME THIS MRNG INTO EARLY AFTN. WITH TEMPS RAPIDLY
FALLING INTO THE LOW-MID 30S BY 12Z LOCALES IN THE SRN TUG HILL
PLATEAU MAY SEE A BRIEF SNOW SHOWER THIS MRNG BFR MIXING WITH RAIN
BY 15Z. ANY LINGERING PCPN WL LKLY BE ALL RAIN BY LATE MRNG INTO THE
AF TN HRS...WITH VRY MINIMAL SNOW ACCUMS EXPECTED. THAT IS, ASSUMING
ANYTHING CAN DVLP WITH VRY LITTLE ACTIVITY EVIDENT ON KBUF RADAR AS
OF 09Z COURTESY OF LOW-LVL DRYING WORKING IN FM THE WEST.
SKIES WL GNRLY BEGIN AS MOCLDY THIS MRNG BFR CLRNG SOUTH OF THE I-88
CORRIDOR BY AFTN. SXNS WEST OF I-81 WL RMN PRTLY-MOCLDY THRU 00Z
WED. THIS WL STUNT TEMPS FM RISING TOO MUCH. ON AVG, EXPECT MAXES TO
BE SOME 20-25 DEGREES LWR THAN YDA WITH HIGHS IN THE MIDDLE-40S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
HIPRES WL BUILD IN FM THE WEST TONIGHT WITH NRLY FLOW TAKING HOLD
ACRS THE REGION. THIS WL KEEP LK CLDS IN ACRS PORTIONS OF THE AREA
AS WINDS SWING ARND FM THE NW AT 00Z TO MORE OF A NRLY FLOW BY 06Z.
LESS OF A FETCH ACRS THE LKS WL LEAD TO MOCLDY DIMINISHING TO PCLDY
OVRNGT WITH MOST AREAS EXPERIENCING SKC. GIVEN VARYING CLD CONDS
EXPECT THAT MIN TEMPS WL DIP WELL INTO THE 20S AT MOST LOCALES WITH
THE EXCEPTION OF THE LK PLAIN.
HIPRES WL SQUAT OVR THE REGION THRU THURSDAY AND BYND. MODERATING
TEMPS CAN BE EXPECTED THRU MIDWEEK. SKIES EXPECTED TO CLD UP FM THE
WEST ON THUR AFTN AS H5 L/WV TROF APPCHS FM THE WEST COURTESY OF UL
LOW OVR HUDSON BAY. HWVR, THIS WL LKLY HV LITTLE IMPACT ON TEMPS
WITH HIGHS EXPECTED IN THE MID-UPR 40S.
&&
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
215 PM TUE UPDATE...
MODELS ARE IN AGREEMENT ON CONTINUED QUIET PERIOD OF DRY WEATHER
THROUGH THE WEEKEND...BUT THEN DEPART CONSIDERABLY ON HOW TO
HANDLE LOCATION AND SIZE OF A SYSTEM HEADING UP OFFSHORE THE COAST
EARLY NEXT WEEK...AND WHETHER WE GET ANY PERIPHERAL IMPACTS AT ALL
FROM IT. REGARDLESS...NOT SEEING ANY SIGNS OF ANOMOLOUSLY WARM NOR
COLD OUTBREAKS...STAYING PRETTY CLOSE TO CLIMATOLOGY OVERALL OR
JUST A SHADE SHORT OF IT IF ANYTHING.
UPPER TROUGH DIGGING INTO WESTERN GREAT LAKES FRIDAY...PINCHES OFF A
SMALL UPPER LOW WHICH HEADS TO THE SOUTHERN APPALACHIAN REGION.
FOR US...STRONG SURFACE HIGH STAYS IN CONTROL. PLENTY OF DRY AIR
AND ONLY A TENUOUS AT BEST CONNECTION FROM THE UPPER LOW WELL TO
OUR SOUTH...TO THE SHEARING OUT NORTHERN STREAM WAVE TO OUR
NORTH. THE ASSOCIATED WEAKENING VORTICITY LOBE ALOFT DOES NOT
EVEN QUITE MAKE IT THROUGH OUR REGION.
AT THIS POINT...GFS AND ECMWF ARE STRUGGLING WITH THE SOUTHERN
UPPER LOW. GFS SIMPLY OPENS IT BACK UP AND PUSHES IT WELL OFF THE
CAROLINA COAST...WITH THE LARGE SURFACE HIGH/RIDGE ACROSS THE
NORTHEAST DOMINANT. SO WITH THE GFS...NO PRECIPITION FORESEEN WITH
NEAR CLIMATOLOGY DAYS AND CHILLY NIGHTS. THE ECMWF MEANWHILE
MAINTAINS THE UPPER LOW...AND TAKES IT UP THE COAST ONCE MEETING
THE GULF STREAM. IT HAS A GRADUAL EVOLUTION IN DEVELOPING A LARGE
IN SIZE...YET INITIALLY NOT VERY DEEP...SURFACE LOW WHICH VERY
SLOWLY SLOGS NORTHWARD AND PERHAPS RETROGRADES SOMEWHAT TO
EVENTUALLY IMPACT OUR WEATHER. TEMPERATURES IN THIS SCENARIO IF IT
WERE TO PAN OUT DO NOT LOOK SUPPORTIVE OF SNOW. THE BIG SURFACE
HIGH TO THE NORTH...REMAINING DOMINANT IN THE GFS...SQUEEZES
FARTHER EAST IN THE ECMWF AND ALLOWS MOISTURE/PERIPHERY OF LOW
PRESSURE TO OOZE TOWARDS THE NORTHEAST EARLY NEXT WEEK. NOT SURE
HOW MUCH STOCK TO PUT IN THE ECMWF SOLUTION...WITH THE ODD LOOK TO
ITS EVOLUTION ESPECIALLY REGARDING THE SURFACE LOW.
UNTIL THIS LARGER SCALE CONUNDRUM CAN BE RESOLVED...FOR NOW I
PLACED ONLY SLIGHT TO LOW CHANCE POPS FOCUSED ON SOUTHERN TO
EASTERN ZONES EARLY NEXT WEEK...SIMILAR TO HPC FORECAST.
&&
.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
18Z UPDATE...
WIND DIRECTION WILL VEER MORE NORTHWESTERLY THIS AFTERNOON. MVFR
TO LOW END MVFR CIGS ARE EXPECTED COURTESY OF LAKE EFFECT AND
FAVORABLE WIND DIRECTION. THAT BEING SAID...NOT ENOUGH COLD AIR
FOR ANY SIGNIFICANT LAKE EFFECT PRECIPITATION. CIGS WILL SCATTER
OUT FOR SOME AS FLOW SLACKENS WHILE VEERING FURTHER TONIGHT...YET
DEVELOP FOR OTHERS AS INVERSION COMPRESSES CLOSER TOT HE
SURFACE...SEE INDIVIDUAL TAFS FOR SPECIFICS. DRY ATMOSPHERE AND
LIGHT NNE TO NE FLOW EVENTUALLY WIN OUT OF WEDNESDAY MORNING WITH
VFR AND HIGH PRESSURE.
OUTLOOK...
WED THROUGH SUN...VFR WITH HIGH PRESSURE OVER THE REGION.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...MDP
NEAR TERM...PVN/RRM
SHORT TERM...PVN
LONG TERM...MDP
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1230 PM EST TUE NOV 13 2012
.SYNOPSIS...
AFTERNOON HIGH TEMPERATURES WILL AVERAGE 15 TO 20 DEGREES COLDER
THAN YESTERDAY COURTESY OF A STRONG COLD FRONT THAT PASSED THROUGH
LAST NIGHT. DRY WEATHER AND SEASONAL TEMPERATURES ARE EXPECTED
THROUGH THE END OF THE WEEK AS HIGH PRESSURE DOMINATES THE WEATHER
PATTERN.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
12 PM UPDATE...LATEST SAT PICS CONTINUE TO SHOW WIDESPREAD STRATO
CU ACROSS THE CWA WITH A FEW BREAKS IN THE WESTERN MOHAWK VALLEY
AND WYOMING VALLEY. OTHER THAN ADJUSTING MAX TEMPS DOWN A BIT MORE
FORECAST IN GOOD SHAPE.
10 AM UPDATE...PRECIP HAS MOVED EAST OF THE REGION WITH THE
CURRENT WEAK LAKE RESPONSE NORTH OF THE FORECAST AREA ALONG THE
LAKE ONTARIO EASTERN SHORE. SATELLITE SHOWS CLOUDY TO MOSTLY
CLOUDY SKIES OVER THE ENTIRE REGION WITH 12Z RAOBS AND RAP MODEL
SOUNDINGS INDICATING A VERY SHALLOW LAYER OF MOISTURE ABOUT 50 MB
DEEP AT THE 850 MB LEVEL. THE MODEL SOUNDINGS INDICATE THIS LAYER
WILL BE VERY STUBBORN TO ERODE UNDER A STRONG SUBSIDENCE
INVERSION. ADJUSTED CLOUD GRIDS TO REFLECT THIS MORE PESSIMISTIC
THINKING OF CLOUDY TO MOSTLY CLOUDY SKIES FOR MUCH OF THE DAY
EXCEPT FOR THE FAR SE FA. DUE TO THIS INCREASED CLOUD COVER
ADJUSTED MAX TEMPS DOWN SLIGHTLY. LOW LEVEL WINDS WILL GRADUALLY
VEER TODAY WITH SCATTERED RAIN/SNOW SHOWERS FOR PRIMARILY NRN
ONEIDA COUNTY POSSIBLY DROPPING INTO THE SYR AREA LATER THIS
AFTERNOON. SNOW ACCUM OF ONLY A FEW TENTHS IN THE HIGHER TERRAIN
OF ONEIDA COUNTY.
615 AM UPDATE...
HV UPPED SNOWFALL TOTALS IN THE CATSKILLS THIS MRNG. AT THE
BINGHAMTON AIRPORT WE MEASURED 1.4 INCHES AND NOT OUT OF THE
QUESTION THAT HIGHER TERRAIN IN THE CATSKILLS MAY SEE UPWARDS OF 4
INCHES. HIGHER REFLECTIVITIES ON RADAR ALONG WITH DUAL-POL
PRODUCTS AND WEBCAMS IN THE REGION SUPPORT THIS THINKING.
HV ALSO TWEAKED HRLY TEMPS AS THEY DROPPED OFF QUICKLY THIS MRNG.
HRLY POP/WX GRIDS LOOK TO BE FAIRLY WELL IN LINE WITH REALITY SO
NO UPDATES NEEDED AT THIS TIME.
PREV DISCUSSIONS BLO...
445 AM UPDATE...
HOW QUICKLY THINGS CAN GO AWRY. JUST AS GRIDS WERE SENT, RAIN
SWITCHED OVR TO SNOW HERE AT KBGM. UPDATED GRIDS THRU 14Z TO ADD
SNOW IN AT ELEVATIONS > 1600 FT. VRY MINIMAL ACCUMS EXPECTED BUT
OVR IN THE WRN CATS MAY SEE AMNTS UPWARDS OF AN INCH BTWN NOW AND
12Z.
4 AM UPDATE... AS OF 07Z CDFNT HAS MVD THRU CWA. BULK OF THE
RAIN, AS EXPECTED, IS BHND THE FRONTAL BNDRY AS UL TROF AND ASSOC
SPEED MAX ROTATE THRU THE REGION BY 15Z. BASED ON PROGRESS OF BACK
EDGE OF MAIN AREA OF PCPN RAIN SHUD BE LOCATED OVR FAR ERN ZONES
BY 12Z AS FCST. EXPECT THIS PCPN WL SHOVE EAST OF FA BY 15Z.
WRLY FLOW BHND FNT AS WELL AS CLD TEMPS ALOFT MAY LEAD TO LK
RESPONSE FOR A TIME THIS MRNG INTO EARLY AFTN. WITH TEMPS RAPIDLY
FALLING INTO THE LOW-MID 30S BY 12Z LOCALES IN THE SRN TUG HILL
PLATEAU MAY SEE A BRIEF SNOW SHOWER THIS MRNG BFR MIXING WITH RAIN
BY 15Z. ANY LINGERING PCPN WL LKLY BE ALL RAIN BY LATE MRNG INTO THE
AFTN HRS...WITH VRY MINIMAL SNOW ACCUMS EXPECTED. THAT IS, ASSUMING
ANYTHING CAN DVLP WITH VRY LITTLE ACTIVITY EVIDENT ON KBUF RADAR AS
OF 09Z COURTESY OF LOW-LVL DRYING WORKING IN FM THE WEST.
SKIES WL GNRLY BEGIN AS MOCLDY THIS MRNG BFR CLRNG SOUTH OF THE I-88
CORRIDOR BY AFTN. SXNS WEST OF I-81 WL RMN PRTLY-MOCLDY THRU 00Z
WED. THIS WL STUNT TEMPS FM RISING TOO MUCH. ON AVG, EXPECT MAXES TO
BE SOME 20-25 DEGREES LWR THAN YDA WITH HIGHS IN THE MIDDLE-40S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
HIPRES WL BUILD IN FM THE WEST TONIGHT WITH NRLY FLOW TAKING HOLD
ACRS THE REGION. THIS WL KEEP LK CLDS IN ACRS PORTIONS OF THE AREA
AS WINDS SWING ARND FM THE NW AT 00Z TO MORE OF A NRLY FLOW BY 06Z.
LESS OF A FETCH ACRS THE LKS WL LEAD TO MOCLDY DIMINISHING TO PCLDY
OVRNGT WITH MOST AREAS EXPERIENCING SKC. GIVEN VARYING CLD CONDS
EXPECT THAT MIN TEMPS WL DIP WELL INTO THE 20S AT MOST LOCALES WITH
THE EXCEPTION OF THE LK PLAIN.
HIPRES WL SQUAT OVR THE REGION THRU THURSDAY AND BYND. MODERATING
TEMPS CAN BE EXPECTED THRU MIDWEEK. SKIES EXPECTED TO CLD UP FM THE
WEST ON THUR AFTN AS H5 L/WV TROF APPCHS FM THE WEST COURTESY OF UL
LOW OVR HUDSON BAY. HWVR, THIS WL LKLY HV LITTLE IMPACT ON TEMPS
WITH HIGHS EXPECTED IN THE MID-UPR 40S.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
1 AM UPDATE...
ONLY MINOR CHANGES. SHOULD BE A QUIET PERIOD WITH DRY WEATHER AND
STEADY TEMPERATURES AT OR SLIGHTLY BELOW SEASONAL NORMALS.
PREVIOUS DISCUSSION...
VERY LITTLE TO TALK ABOUT AGAIN THIS AFTERNOON AS MODELS
CONTINUE TO ADVERTISE A VERY QUIET PERIOD WITH HIGH PRESSURE IN
FIRM CONTROL THROUGH AT LEAST SATURDAY. NORTHERN HEMISPHERIC
500-MB TEMP/HEIGHT PROGS SHOW ZONAL FLOW PREVAILING THROUGH THE
PERIOD TO OUR NORTH ACROSS CENTRAL/NORTHERN CANADA...EFFECTIVELY
KEEPING ANY TRUE ARCTIC AIR ACROSS THE HIGHER LATITUDES. WITH THIS
BEING THE CASE...NO SIGNIFICANT COOL DOWNS ARE ANTICIPATED FROM
THIS VANTAGE POINT WITH NEAR NORMAL TEMPS EXPECTED THROUGH THE
PERIOD. ONE FEATURE THAT DOES WARRANT SOME WATCHING WILL BE A
SOUTHERN STREAM WAVE WORKING THROUGH THE SOUTHEAST/TENN RVR VLY
TOWARDS LATE WEEK. THE GFS IN PARTICULAR DOES DEVELOP CYCLOGENESIS
OFF THE SOUTHEAST COAST WITH THE MODEL THEN TAKING THE SFC LOW AND
UPPER WAVE SLOWLY UP THE EAST COAST. EXTENT OF NORTHWARD PROGRESS
REMAINS IN QUESTION THIS AFTERNOON AS BOTH GFS AND ECMWF SHOW
STRONG LOWER TROPOSPHERIC RIDGING ACROSS THE NORTHEASTERN US
THROUGH THE WEEKEND WHICH COULD SERVE TO BLOCK NORTHWARD PROGRESS
OF THE DISTURBANCE. FOR NOW HAVE ELECTED TO LEAVE ANY MENTION OF
PRECIP OUT OF THE FCST...HOWEVER IF TRENDS CONTINUE TO SHOW HIGH
PRESSURE SHIFTING TO THE NORTH...SUBSEQUENT UPDATES MAY HAVE TO
INTRODUCE POPS FOR EARLY NEXT WEEK.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
18Z UPDATE...
WIND DIRECTION WILL VEER MORE NORTHWESTERLY THIS AFTERNOON. MVFR
TO LOW END MVFR CIGS ARE EXPECTED COURTESY OF LAKE EFFECT AND
FAVORABLE WIND DIRECTION. THAT BEING SAID...NOT ENOUGH COLD AIR
FOR ANY SIGNIFICANT LAKE EFFECT PRECIPITATION. CIGS WILL SCATTER
OUT FOR SOME AS FLOW SLACKENS WHILE VEERING FURTHER TONIGHT...YET
DEVELOP FOR OTHERS AS INVERSION COMPRESSES CLOSER TOT HE
SURFACE...SEE INDIVIDUAL TAFS FOR SPECIFICS. DRY ATMOSPHERE AND
LIGHT NNE TO NE FLOW EVENTUALLY WIN OUT OF WEDNESDAY MORNING WITH
VFR AND HIGH PRESSURE.
OUTLOOK...
WED THROUGH SUN...VFR WITH HIGH PRESSURE OVER THE REGION.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...PVN/RRM
NEAR TERM...PVN/RRM
SHORT TERM...PVN
LONG TERM...CMG/TAC
AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1215 PM EST TUE NOV 13 2012
.SYNOPSIS...
AFTER A COLD START THIS MORNING, AFTERNOON HIGH TEMPERATURES WILL
AVERAGE 15 TO 20 DEGREES COLDER THAN YESTERDAY COURTESY OF A STRONG
COLD FRONT. HIGH TEMPERATURES TODAY CAN BE EXPECTED TO REMAIN IN THE
40S. DRY WEATHER AND SEASONAL TEMPERATURES ARE EXPECTED THROUGH THE
END OF THE WEEK AS HIGH PRESSURE DOMINATES THE WEATHER PATTERN.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
12 PM UPDATE...LATEST SAT PICS CONTINUE TO SHOW WIDESPREAD STRATO
CU ACROSS THE CWA WITH A FEW BREAKS IN THE WESTERN MOHAWK VALLEY
AND WYOMING VALLEY. OTHER THAN ADJUSTING MAX TEMPS DOWN A BIT MORE
FORECAST IN GOOD SHAPE.
10 AM UPDATE...PRECIP HAS MOVED EAST OF THE REGION WITH THE
CURRENT WEAK LAKE RESPONSE NORTH OF THE FORECAST AREA ALONG THE
LAKE ONTARIO EASTERN SHORE. SATELLITE SHOWS CLOUDY TO MOSTLY
CLOUDY SKIES OVER THE ENTIRE REGION WITH 12Z RAOBS AND RAP MODEL
SOUNDINGS INDICATING A VERY SHALLOW LAYER OF MOISTURE ABOUT 50 MB
DEEP AT THE 850 MB LEVEL. THE MODEL SOUNDINGS INDICATE THIS LAYER
WILL BE VERY STUBBORN TO ERODE UNDER A STRONG SUBSIDENCE
INVERSION. ADJUSTED CLOUD GRIDS TO REFLECT THIS MORE PESSIMISTIC
THINKING OF CLOUDY TO MOSTLY CLOUDY SKIES FOR MUCH OF THE DAY
EXCEPT FOR THE FAR SE FA. DUE TO THIS INCREASED CLOUD COVER
ADJUSTED MAX TEMPS DOWN SLIGHTLY. LOW LEVEL WINDS WILL GRADUALLY
VEER TODAY WITH SCATTERED RAIN/SNOW SHOWERS FOR PRIMARILY NRN
ONEIDA COUNTY POSSIBLY DROPPING INTO THE SYR AREA LATER THIS
AFTERNOON. SNOW ACCUM OF ONLY A FEW TENTHS IN THE HIGHER TERRAIN
OF ONEIDA COUNTY.
615 AM UPDATE...
HV UPPED SNOWFALL TOTALS IN THE CATSKILLS THIS MRNG. AT THE
BINGHAMTON AIRPORT WE MEASURED 1.4 INCHES AND NOT OUT OF THE
QUESTION THAT HIGHER TERRAIN IN THE CATSKILLS MAY SEE UPWARDS OF 4
INCHES. HIGHER REFLECTIVITIES ON RADAR ALONG WITH DUAL-POL
PRODUCTS AND WEBCAMS IN THE REGION SUPPORT THIS THINKING.
HV ALSO TWEAKED HRLY TEMPS AS THEY DROPPED OFF QUICKLY THIS MRNG.
HRLY POP/WX GRIDS LOOK TO BE FAIRLY WELL IN LINE WITH REALITY SO
NO UPDATES NEEDED AT THIS TIME.
PREV DISCUSSIONS BLO...
445 AM UPDATE...
HOW QUICKLY THINGS CAN GO AWRY. JUST AS GRIDS WERE SENT, RAIN
SWITCHED OVR TO SNOW HERE AT KBGM. UPDATED GRIDS THRU 14Z TO ADD
SNOW IN AT ELEVATIONS > 1600 FT. VRY MINIMAL ACCUMS EXPECTED BUT
OVR IN THE WRN CATS MAY SEE AMNTS UPWARDS OF AN INCH BTWN NOW AND
12Z.
4 AM UPDATE... AS OF 07Z CDFNT HAS MVD THRU CWA. BULK OF THE
RAIN, AS EXPECTED, IS BHND THE FRONTAL BNDRY AS UL TROF AND ASSOC
SPEED MAX ROTATE THRU THE REGION BY 15Z. BASED ON PROGRESS OF BACK
EDGE OF MAIN AREA OF PCPN RAIN SHUD BE LOCATED OVR FAR ERN ZONES
BY 12Z AS FCST. EXPECT THIS PCPN WL SHOVE EAST OF FA BY 15Z.
WRLY FLOW BHND FNT AS WELL AS CLD TEMPS ALOFT MAY LEAD TO LK
RESPONSE FOR A TIME THIS MRNG INTO EARLY AFTN. WITH TEMPS RAPIDLY
FALLING INTO THE LOW-MID 30S BY 12Z LOCALES IN THE SRN TUG HILL
PLATEAU MAY SEE A BRIEF SNOW SHOWER THIS MRNG BFR MIXING WITH RAIN
BY 15Z. ANY LINGERING PCPN WL LKLY BE ALL RAIN BY LATE MRNG INTO THE
AFTN HRS...WITH VRY MINIMAL SNOW ACCUMS EXPECTED. THAT IS, ASSUMING
ANYTHING CAN DVLP WITH VRY LITTLE ACTIVITY EVIDENT ON KBUF RADAR AS
OF 09Z COURTESY OF LOW-LVL DRYING WORKING IN FM THE WEST.
SKIES WL GNRLY BEGIN AS MOCLDY THIS MRNG BFR CLRNG SOUTH OF THE I-88
CORRIDOR BY AFTN. SXNS WEST OF I-81 WL RMN PRTLY-MOCLDY THRU 00Z
WED. THIS WL STUNT TEMPS FM RISING TOO MUCH. ON AVG, EXPECT MAXES TO
BE SOME 20-25 DEGREES LWR THAN YDA WITH HIGHS IN THE MIDDLE-40S.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
HIPRES WL BUILD IN FM THE WEST TONIGHT WITH NRLY FLOW TAKING HOLD
ACRS THE REGION. THIS WL KEEP LK CLDS IN ACRS PORTIONS OF THE AREA
AS WINDS SWING ARND FM THE NW AT 00Z TO MORE OF A NRLY FLOW BY 06Z.
LESS OF A FETCH ACRS THE LKS WL LEAD TO MOCLDY DIMINISHING TO PCLDY
OVRNGT WITH MOST AREAS EXPERIENCING SKC. GIVEN VARYING CLD CONDS
EXPECT THAT MIN TEMPS WL DIP WELL INTO THE 20S AT MOST LOCALES WITH
THE EXCEPTION OF THE LK PLAIN.
HIPRES WL SQUAT OVR THE REGION THRU THURSDAY AND BYND. MODERATING
TEMPS CAN BE EXPECTED THRU MIDWEEK. SKIES EXPECTED TO CLD UP FM THE
WEST ON THUR AFTN AS H5 L/WV TROF APPCHS FM THE WEST COURTESY OF UL
LOW OVR HUDSON BAY. HWVR, THIS WL LKLY HV LITTLE IMPACT ON TEMPS
WITH HIGHS EXPECTED IN THE MID-UPR 40S.
&&
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
1 AM UPDATE...
ONLY MINOR CHANGES. SHOULD BE A QUIET PERIOD WITH DRY WEATHER AND
STEADY TEMPERATURES AT OR SLIGHTLY BELOW SEASONAL NORMALS.
PREVIOUS DISCUSSION...
VERY LITTLE TO TALK ABOUT AGAIN THIS AFTERNOON AS MODELS
CONTINUE TO ADVERTISE A VERY QUIET PERIOD WITH HIGH PRESSURE IN
FIRM CONTROL THROUGH AT LEAST SATURDAY. NORTHERN HEMISPHERIC
500-MB TEMP/HEIGHT PROGS SHOW ZONAL FLOW PREVAILING THROUGH THE
PERIOD TO OUR NORTH ACROSS CENTRAL/NORTHERN CANADA...EFFECTIVELY
KEEPING ANY TRUE ARCTIC AIR ACROSS THE HIGHER LATITUDES. WITH THIS
BEING THE CASE...NO SIGNIFICANT COOL DOWNS ARE ANTICIPATED FROM
THIS VANTAGE POINT WITH NEAR NORMAL TEMPS EXPECTED THROUGH THE
PERIOD. ONE FEATURE THAT DOES WARRANT SOME WATCHING WILL BE A
SOUTHERN STREAM WAVE WORKING THROUGH THE SOUTHEAST/TENN RVR VLY
TOWARDS LATE WEEK. THE GFS IN PARTICULAR DOES DEVELOP CYCLOGENESIS
OFF THE SOUTHEAST COAST WITH THE MODEL THEN TAKING THE SFC LOW AND
UPPER WAVE SLOWLY UP THE EAST COAST. EXTENT OF NORTHWARD PROGRESS
REMAINS IN QUESTION THIS AFTERNOON AS BOTH GFS AND ECMWF SHOW
STRONG LOWER TROPOSPHERIC RIDGING ACROSS THE NORTHEASTERN US
THROUGH THE WEEKEND WHICH COULD SERVE TO BLOCK NORTHWARD PROGRESS
OF THE DISTURBANCE. FOR NOW HAVE ELECTED TO LEAVE ANY MENTION OF
PRECIP OUT OF THE FCST...HOWEVER IF TRENDS CONTINUE TO SHOW HIGH
PRESSURE SHIFTING TO THE NORTH...SUBSEQUENT UPDATES MAY HAVE TO
INTRODUCE POPS FOR EARLY NEXT WEEK.
&&
.AVIATION /17Z TUESDAY THROUGH SATURDAY/...
630 AM UPDATE...
MIXED PRECIP ON THE WAY OUT WITH ONLY KAVP HAVING RAIN NOW. THIS
SHOULD END BY 14Z. SOME MVFR CIGS AND MAYBE MVFR VSBYS AT KAVP
ALSO UNTIL 14Z. BEHIND THE FRONT CIGS QUICKLY RISE TO VFR AND
STAY THERE TODAY. KRME AND KBGM MAY ALSO HAVE AN HOUR OR TWO OF
MVFR RIGHT AT THE START.
DURING THE DAY TODAY CONTINUED BKN TO OVC SKIES BUT VFR. WEAK LAKE
ENHANCEMENT WITH WEST LL FLOW SHIFTING TO NW. LATE THIS AFTN TO
SUNSET SKIES WILL BECOME SCATTERED OR CLEAR AND REMAIN THAT WAY
TONIGHT. BEST CHANCE OF CLOUDS CLOSER TO THE LAKE...BUT LOW LEVEL
FLOW GOES AROUND TO NE WITH CONDITIONAL LAKE INSTABILITY. NOT
EXPECTING MANY CLOUDS TONIGHT.
W TO NW WINDS INCREASING TO 8 KTS THIS MORNING THEN CONTINUING
INTO THE AFTN. TONIGHT WINDS LIGHT TO CALM...MOSTLY FROM THE NW
TO N.
OUTLOOK...
WED THROUGH SAT...VFR WITH HIGH PRESSURE OVER THE REGION.
&&
.BGM WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NY...NONE.
&&
$$
SYNOPSIS...PVN/RRM
NEAR TERM...PVN/RRM
SHORT TERM...PVN
LONG TERM...CMG/TAC
AVIATION...TAC
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1219 PM EST TUE NOV 13 2012
.SYNOPSIS...
A STRONG COLD FRONT WILL PUSH OFFSHORE THIS AFTERNOON...FOLLOWED BY
CHILLY CANADIAN AIR. HIGH PRESSURE WILL BUILD TO OUR NORTH THIS
WEEK...EXTENDING INTO THE CAROLINAS. A WEAK LOW PRESSURE SYSTEM WILL
DEVELOP OFFSHORE THURSDAY AND MOVE NORTHEAST. ANOTHER LOW WILL
DEVELOP OFFSHORE THIS WEEKEND WITH INCREASING CHANCES FOR RAIN.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1215 PM TUESDAY...THE COLD FRONT HAS BEEN LOCATED BY RADAR AND
SURFACE OBSERVATIONS ON THE PENDER COUNTY COASTLINE...EXTENDING
SOUTHWEST THROUGH WILMINGTON AND TO ABOUT 5 MILES WEST OF NORTH
MYRTLE BEACH. THE FRONT SHOULD CONTINUE MOVING STEADILY OFF THE
COAST THIS AFTERNOON. A HEALTHY CLUSTER OF SURFACE-BASED CONVECTION
(SHOWERS) WILL MOVE ACROSS WILMINGTON WITHIN THE NEXT HOUR...WITH
LIGHTER SHOWERS FROM ELEVATED INSTABILITY CONTINUING INLAND
ESPECIALLY IN THE LUMBERTON AND DILLON VICINITY. TEMPERATURES HAVE
PEAKED AT ALL LOCATIONS AND STEADY TO SLOWLY FALLING TEMPERATURES
ARE EXPECTED DUE TO COLD ADVECTION THROUGH THE AFTERNOON. PREVIOUS
DISCUSSION FROM 10 AM FOLLOWS...
THE SURFACE COLD FRONT EXTENDS FROM NEAR ELIZABETHTOWN TO
WHITEVILLE...ACROSS THE WESTERN PORTIONS OF HORRY COUNTY TO NEAR
KINGSTREE IN SOUTH CAROLINA. THE 11Z HRRR WAS ABOUT ONE HOUR FAST
WITH THE FRONT BUT OTHERWISE LOOKED TO BE A GOOD FIT FOR THE SHAPE
AND FORWARD SPEED OF THE BOUNDARY...PRESSING IT OFFSHORE BY 18-19Z
IN ALL AREAS.
VISIBLE SATELLITE SHOWS A NARROW ZONE OF MAINLY CLEAR SKIES JUST IN
ADVANCE OF THE FRONT WITH TEMPERATURES RISING INTO THE LOWER 70S
ALONG THE SC COAST. THESE WARMER TEMPERATURES MAY EXTEND INTO
EXTREME SE NORTH CAROLINA IN THE NEXT 1-2 HOURS BEFORE THE FRONT
SWEEPS THROUGH AND MUCH COLDER AIR BUILDS IN. HIGH TEMPERATURES HAVE
ALREADY BEEN RECORDED INLAND AND STEADY TEMPERATURES ARE ANTICIPATED
FOR THE REMAINDER OF THE DAY NEAR AND WEST OF I-95.
RADAR SHOWS ONE BATCH OF SHOWERS NEAR AND EAST OF CAPE FEAR
ASSOCIATED WITH UNSTABLE AIR ADVECTING NORTH FROM THE WESTERN EDGE
OF THE GULF STREAM. SHOWERS ACROSS THE CENTRAL CAROLINAS APPEAR TO
BE LINKED TO SMALL ELEVATED INSTABILITY IN THE 900-700 MB LAYER
ASSISTED BY SYNOPTIC-SCALE LIFT FROM THE RIGHT-ENTRANCE REGION OF A
FAVORABLY POSITIONED 300 MB JET ACROSS THE MID-ATLANTIC AND EASTERN
GREAT LAKES. THIS REGION OF ENHANCED SHOWER ACTIVITY SHOULD ADVECT
SLOWLY NORTHEASTWARD THROUGH THE AFTERNOON.
&&
.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 AM TUESDAY...A LARGE AREA OF HIGH PRESSURE WILL BE CENTERED
NORTH OF NY STATE ON WEDNESDAY WITH A RIDGE AXIS/COOL AIR WEDGE
EXTENDING DOWN INTO THE CAROLINAS. THIS VERY SHALLOW COOL AIR MASS
WILL KEEP TEMPS WELL BELOW CLIMO, THE EXTENT TO WHICH WILL DEPEND ON
HOW EXTENSIVE CLOUD COVER ENDS UP BEING. AS IT IS CLOUD COVER SHOULD
BE QUITE EXTENSIVE BUT A FEW BREAKS DURING PEAK HEATING COULD REALLY
ADD SEVERAL DEGREES TO HIGH TEMPS. AS THE DAY WEARS ON HOWEVER LOW
LEVEL FLOW INCREASES JUST ATOP THE SURFACE AIRMASS IN RESPONSE TO
AN APPROACHING SHORTWAVE. THIS FEATURE SWINGS THROUGH BY THURSDAY
MORNING AND COULD TOUCH OFF WIDELY SCATTERED VERY LIGHT SHOWERS.
WEAK SUBSIDENCE THURSDAY AFTERNOON BRINGS BACK THE ORIGINAL FORECAST
ISSUE OF FIGURING OUT HOW CLOUDY THE DAY ENDS UP (STILL LIKELY
WITHIN `MOSTLY CLOUDY`) AND THE EXTENT TO WHICH THIS ENDS UP KEEPING
HIGH TEMPS BELOW CLIMO.
&&
.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 3 AM TUESDAY...HIGH PRESSURE CENTERED OVER NY STATE RIDGING
INTO THE CAROLINAS WILL MERGE WITH ANOTHER HIGH MOVING IN FROM THE
WEST OVER THE WEEKEND. END RESULT WILL BE SURFACE PRESSURES
CONTINUING TO ADVECT IN FROM POINTS NORTH KEEPING TEMPS BELOW CLIMO
ESPECIALLY BY DAY. A NORTHERN BRANCH TROUGH WILL ALSO BECOME
INCREASINGLY BAGGY AND EVENTUALLY CUTOFF WEAKLY OVER GULF STATES
OVER THE WEEKEND. THE RESULTING ASCENT AHEAD OF THIS FEATURE WILL
CAUSE PRESSURES TO FALL WELL OFF THE COAST ALONG THE OLD FRONTAL
BOUNDARY. THIS WILL INITIALLY BE A VERY GRADUAL PROCESS THROUGH
SATURDAY NIGHT INTO MOST OF SUNDAY. LATER SUNDAY AS THE UPPER WAVE
GETS CLOSER TO THE COAST/FRONT BAROCLINIC INSTABILITY LEADS TO
FEEDBACK THAT STRENGTHENS THE FEATURES BOTH SURFACE AND ALOFT. HOW
MUCH RAINFALL THIS ENDS UP LEADING TO IS TOUGH TO SAY SINCE MODELS
DIVERGE ON THE STRENGTH AND THE LATITUDE OF THE SYSTEMS EVOLUTION.
THE EC, WHICH HAS BEEN QUITE ACCURATE ALONG THE EAST COAST AS OF
LATE, IS THE STRONGEST AND FURTHEST TO THE SOUTH AND WOULD IMPLY
SOME DECENT RAINS LOCALLY. THIS SOLUTION IS NOW GETTING SUPPORT FROM
THE 00Z CANADIAN MODEL. THE GFS HAS BEEN VERY CONSISTENT IN A
FLATTER AND FURTHER NORTH CYCLOGENESIS KEEPING RAINFALL CONFINED TO
THE IMMEDIATE (MAINLY NC) COAST THIS FAR SOUTH. THIS HAS BEEN THE
PREFERRED SOLUTION BUT THE AGREEMENT BETWEEN THE OTHERS IS GETTING
HARD TO IGNORE AND THE WEEKEND FORECAST WILL BE TWEAKED IN A MORE
PESSIMISTIC DIRECTION. MONDAYS FORECAST IS EVEN MORE UNCERTAIN AS
THE FASTER SOLUTIONS IMPLY DRY AND COOL AIR ADVECTION WHEREAS THE
SLOWEST POSSIBILITIES COULD STILL MEAN WRAPAROUND MOISTURE.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AS OF 18Z...WIDESPREAD MVFR/IFR CIGS ACROSS THE INLAND COUNTIES WITH
NNE WINDS 10 TO 15 KNOTS BEHIND THE COLD FRONT THAT PASSED THROUGH
THIS MORNING. THE FRONT IS EXPECTED TO REACH THE COASTAL SITES
AROUND 18Z...WHERE CIGS HAVE ALREADY LOWERED TO MVFR LEVELS AHEAD OF
THE FRONT. MORE SHOWERS ARE DEVELOPING ALONG THE BOUNDARY...AND THE
BEST RAIN CHANCES THIS AFTERNOON APPEAR TO BE AT THE COASTAL
TERMS...ESPECIALLY KILM. HOWEVER...THE BIGGEST AVIATION IMPACT IN
THIS TAF PERIOD IS THE REDUCED CIGS ACROSS THE CWA. MVFR/IFR STRATUS
IS EXPECTED ALONG THE COAST TONIGHT...WHILE PREDOMINANTLY MVFR CIGS
ARE LIKELY AT THE INLAND TERMS. LOW LEVEL CLOUD COVER WILL LINGER
THROUGH THE REST OF THE VALID PERIOD...BUT SHOULD LIFT TO MVFR/VFR
LEVELS BY LATE WED MORNING. NNE WINDS 10 TO 12 KNOTS ARE EXPECTED
THROUGH WED AFTERNOON.
EXTENDED OUTLOOK...POST FRONTAL STRATUS POSSIBLE WED AND EARLY
THURS. OCCASIONAL LIGHT PRECIP IS POSSIBLE THURS THROUGH SAT.
&&
.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 1215 PM TUESDAY...NO SIGNIFICANT CHANGES NEEDED FROM THE
PREVIOUS UPDATE. THE FRONT IS MOVING OFF THE PENDER COUNTY COAST
CURRENTLY AND SHOULD SWEEP ACROSS THE REMAINDER OF THE COASTAL
WATERS WITHIN THE NEXT 2 HOURS. NORTH WINDS WILL INCREASE TOWARD 15
KNOTS WITH SOME HIGHER GUSTS LATE IN THE DAY. PREVIOUS DISCUSSION
FROM 10 AM FOLLOWS...
THE COLD FRONT IS CURRENTLY 40-60 MILES INLAND FROM THE COAST AND
SHOULD REACH THE BEACHES EARLY THIS AFTERNOON...ACCOMPANIED BY A
RAPID SHIFT TO NORTH WINDS AND AN INCREASE IN SPEEDS TO AROUND 15
KNOTS. WINDS WILL STEADILY INCREASE THIS EVENING AND SMALL CRAFT
ADVISORY CONDITIONS STILL APPEAR LIKELY OVERNIGHT. SHOWERS ARE MOST
NUMEROUS NEAR AND EAST OF CAPE FEAR THIS MORNING ALTHOUGH THERE IS
ENOUGH INSTABILITY IN THE ATMOSPHERE TO SUPPORT SHOWER DEVELOP
ALMOST ANYWHERE THIS AFTERNOON INTO TONIGHT. SEAS CURRENTLY RANGE
FROM 2 FT AT THE OCEAN CREST PIER ON OAK ISLAND TO AROUND 4 FT AT
THE FRYING PAN SHOALS BUOY OFFSHORE. LITTLE CHANGE WILL OCCUR UNTIL
AFTER THE FRONT PUSHES OFFSHORE THIS AFTERNOON...AT WHICH POINT SEAS
WILL GRADUALLY BUILD TO 3-6 FT TONIGHT...HIGHEST OFFSHORE.
SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 AM TUESDAY...PINCHED GRADIENT IN A POST FRONTAL
NORTHEASTERLY FLOW REGIME ON WEDNESDAY. A SMALL CRAFT ADVISORY
APPEARS LIKELY FOR MOST OF THE AREA. SOME WAVE SHADOWING MAY CALL
FOR JUST A SCEC HOWEVER OVER HORRY COUNTY WATERS. A SMALL DECREASE
IN THE WINDS IS EXPECTED EITHER THURSDAY OR THURSDAY NIGHT AS THE
FRONT SLIPS FURTHER OFFSHORE AND THIS MAY LEAD TO A BRIEF WINDOW
WHERE SCA IS NO LONGER NEEDED. AT A MINIMUM IT SEEMS LIKELY THAT
SCEC CAUTIONARY HEADLINES WILL CONTINUE.
LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 3 AM TUESDAY...HEADLINES ANTICIPATED THE ENTIRE PERIOD.
FRONTAL BOUNDARY STAYS WELL OFFSHORE WITH SURFACE HIGH PRESSURE
RIDGING DOWN INTO THE CAROLINAS FROM POINTS WELL TO THE NORTH.
COASTAL WASTERS FORECAST ZONES LIE IN THE GRADIENT BETWEEN. ON
SATURDAY GRADUAL FALLING PRESSURE ALONG THE FRONT WILL BOLSTER THE
GRADIENT AND ANY WATERS THAT HAD BEEN TEETERING NEAR THE SCEC/SCA
THRESHOLDS WILL BE PUSHED INTO ADVISORY REALM BY BOTH WIND AND SEAS.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON TO 7 PM EST
WEDNESDAY FOR AMZ250-252.
&&
$$
SYNOPSIS...TRA
NEAR TERM...TRA
SHORT TERM...MBB
LONG TERM...MBB
AVIATION...BJR
AREA FORECAST DISCUSSION
NWS NORMAN OK
1155 AM CST TUE NOV 13 2012
.AVIATION...
VFR WILL CONTINUE TO APPLY THROUGH THE FORECAST PERIOD. EXPECT
SOUTH WINDS AROUND 10 TO 15 KT WITH SLIGHTLY STRONGER GUSTS
THROUGH THIS AFTERNOON. A FEW HIGH CLOUDS WILL PASS OVERHEAD.
THE WINDS WILL DECREASE NEAR SUNSET TONIGHT.
&&
.PREV DISCUSSION... /ISSUED 1049 AM CST TUE NOV 13 2012/
UPDATE...
INCREASED THE SOUTHERN WINDS A LITTLE ACROSS WESTERN HALF OF
OKLAHOMA BASED ON CURRENT TRENDS AND NEW RUC OUTPUT. ALSO LOWERED
DEWPOINTS WHERE DEEPER MIXING WILL OCCUR. ELEVATED FIRE DANGER
ACROSS FAR WESTERN OKLAHOMA AND ADJACENT PARTS OF NORTH TEXAS
PRIMARILY DUE TO THE INCREASED WIND.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 32 58 34 62 / 0 0 0 0
HOBART OK 29 59 33 62 / 0 0 0 0
WICHITA FALLS TX 32 63 36 66 / 0 0 0 0
GAGE OK 24 60 30 61 / 0 0 0 0
PONCA CITY OK 29 58 32 59 / 0 0 0 0
DURANT OK 33 59 35 61 / 0 0 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
11/03/03
AREA FORECAST DISCUSSION
NWS NORMAN OK
1049 AM CST TUE NOV 13 2012
.UPDATE...
INCREASED THE SOUTHERN WINDS A LITTLE ACROSS WESTERN HALF OF
OKLAHOMA BASED ON CURRENT TRENDS AND NEW RUC OUTPUT. ALSO LOWERED
DEWPOINTS WHERE DEEPER MIXING WILL OCCUR. ELEVATED FIRE DANGER
ACROSS FAR WESTERN OKLAHOMA AND ADJACENT PARTS OF NORTH TEXAS
PRIMARILY DUE TO THE INCREASED WIND.
&&
.PRELIMINARY POINT TEMPS/POPS...
OKLAHOMA CITY OK 58 32 58 34 / 0 0 0 0
HOBART OK 57 29 59 33 / 0 0 0 0
WICHITA FALLS TX 58 32 63 36 / 0 0 0 0
GAGE OK 58 24 60 30 / 0 0 0 0
PONCA CITY OK 56 29 58 32 / 0 0 0 0
DURANT OK 58 33 59 35 / 0 0 0 0
&&
.OUN WATCHES/WARNINGS/ADVISORIES...
OK...NONE.
TX...NONE.
&&
$$
11/03
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
955 AM MST TUE NOV 13 2012
.UPDATE...16Z SURFACE ANALYSIS HAD WEAK TROUGH OVER THE CWA...A
REFLECTION OF WEAK SHORTWAVE OVER WESTERN SD/EASTERN WY PER WATER
VAPOUR. SYSTEM MOISTURE STARVED...WITH RETURNS ON RADAR MOSTLY
ALOFT. BEST REFLECTIVITY LIKELY REACHING THE GROUND...BUT IN LIGHT
FASHION OVER SOUTH CENTRAL SD THROUGH THIS AFTERNOON.
WILL ADJUST POPS TO MATCH CURRENT RADAR TRENDS AND TWEAK
TEMPERATURES FOR 12Z KUNR SOUNDING.
&&
.AVIATION...18Z TAFS
VFR CONDITIONS CAN BE EXPECTED THROUGH TONIGHT AS A WEAK UPPER LEVEL
DISTURBANCE MOVES EAST OF THE REGION THIS AFTERNOON. A FEW LIGHT
RAIN SHOWERS/SPRINKLES ARE STILL POSSIBLE ACROSS SOUTH CENTRAL SD
THROUGH EARLY AFTERNOON.
&&
.PREV DISCUSSION... /ISSUED 403 AM MST TUE NOV 13 2012/
WENT AHEAD AND REMOVED ZR CHANCES THIS MORNING. RELATIVELY WEAK
LIFT IS SUPPORTING MAINLY OVERCAST SKY WITH AREAS OF VIRGA. IF
PRECIP DOES MATERIALIZE...EXPECT IT WOULD BE IN THE FORM OF
FLURRIES THIS MORNING GIVEN A DIMINISHING WARM NOSE. THIS IS IN
LINE WITH THE LATEST RAP PROFILES. ALL ELSE IN GOOD SHAPE.
PREV DISCUSSION... /ISSUED 257 AM MST TUE NOV 13 2012/
FAST DISTURBED WESTERLY FLOW WILL REMAIN IN PLACE IN THE PERIOD
WITH 36 HOUR PHASE VELOCITY FAVORED IN MODEL CONSENSUS. MID LEVEL
DISTURBANCE IN THE PROCESS OF ADVECTING EAST TROUGH MT/WY/CO AS OF
09Z. THIS SYSTEM WILL QUICKLY ADVANCE EAST THROUGH THE NORTHERN
PLAINS TODAY...BRINGING ONLY A SLIGHT CHANCE FOR PRECIP TO THE
AREA. ANOTHER DISTURBANCE NOW ENTERING THE PAC NW WILL AFFECT THE
AREA WED...WITH INCREASED LIFT SUPPORTING INCREASING CLOUDS ACROSS
THE REGION. LACK OF MOISTURE WITH BOTH SYSTEMS WILL SUPPORT A
MAINLY DRY FORECAST /ESP WED/ WITH QUIET WEATHER EXPECTED IN THE
PERIOD.
TODAY...FAST MOVING IMPULSE WILL CONTINUE TO SUPPORT BROAD ASCENT
OVERT THE REGION INTO THE AFTERNOON. THIS WILL SUPPORT OVERCAST
CONDITIONS FOR MOST OF THE FA...WITH CLEARING WEST TO EAST DURING THE
AFTERNOON. DISMAL MOISTURE PROFILES WITH OVERALL WEAK
WAA/FRONTOGENETICAL RESPONSE WILL SUPPORT VERY SMALL PRECIP
CHANCES...WITH MOST NUMERICAL GUIDANCE NOT SUPPORTING MUCH IN THE
WAY OF QPF. DID RETAIN LOW POPS ACROSS THE NORTHERN 2/3 ENACTING A
TIME SHIFT FOR THE AFTERNOON. IF PRECIP DOES MATERIALIZE THIS
MORNING...THERMAL PROFILES WOULD SUPPORT MAINLY SNOW WITH THE
POSSIBILITY OF SOME ZR GIVEN SFC T/S BELOW 32F AND A WARM NOSE JUST
OFF THE SFC GREATER THAN 2.5C. THIS LINES UP WITH SREF PRECIP TYPE
PROBS AND GFS DOMINANT PROGS. CLEARING EXPECTED THIS EVENING WITH
INCREASING HIGH CLOUDS W-E LATE IN THE NIGHT PER THE NEXT ADVANCING
UPPER IMPULSE. THIS IMPULSE WILL ALSO HELP TO KEEP THE BL PARTIALLY
MIXED WITH WARM PROFILES JUST OFF THE SFC...HELPING TO QUELL T FALLS
SOME.
WED/THUR...NEXT IMPULSE WILL ADV THROUGH THE NORTHERN PLAINS WITH
THE BULK OF FORCING REMAINING WELL NORTH OF THE REGION. THUS...ONLY
AN INCREASE IN CLOUDS EXPECTED. CAA ON THE BACKSIDE OF THIS SYSTEM
IS PROGGED TO BE A LITTLE MORE AGGRESSIVE WITH THE LATEST MODEL
RUNS...A CONTINUED TREND IN THE 06Z NAM. THUS...HAVE COOLED NORTHERN
AREAS DOWN WED NIGHT GIVEN FROPA AND CLEARING SKIES. HIGH
PRESSURE WILL SETTLE OVER THE REGION THUR...AS LL FLOW VEERS AROUND
TO E-SE PER THE NEXT MID LEVEL DISTURBANCE. STAUNCH PRESSURE FALLS
AND WAA THUR NIGHT WILL SUPPORT BREEZY CONDITIONS...ESP OVER NE WY.
HAVE BUMPED WINDS UP AND ADJUSTED MIN T/S PER EXPECTED TURBULENT
MIXING.
EXTENDED...WILL KEEP DRY FORECAST FOR THE EXTENDED PERIOD AS NEAR
ZONAL FLOW PERSISTS ACROSS THE REGION. WEAK DISTURBANCES IN THE FLOW
WILL LIKELY BRING SOME CLOUDINESS FROM TIME TO TIME...BUT CHANCES
FOR PCPN LOOK TO BE MINIMAL. TEMPERATURES WILL BE NEAR TO SLIGHTLY
ABOVE AVERAGE THROUGH THE PERIOD...WITH HIGHS EXPECTED TO MOSTLY BE
IN THE MID 40S TO MID 50S.
&&
.UNR WATCHES/WARNINGS/ADVISORIES...
SD...NONE.
WY...NONE.
&&
$$
SHORT TERM...WFO UNR
LONG TERM...WFO UNR
AVIATION...26
UPDATE...HELGESON
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
1228 PM CST TUE NOV 13 2012
.DISCUSSION...QUICK UPDATE...BASED ON TIDE LEVELS OVER THE
NORTHEAST (WHERE WITH NORTHEAST WINDS PILING UP OF WATER HAS NOT
BEEN AS GREAT)...DROPPED THE COASTAL FLOOD ADVISORY FOR THE
NORTHERN AREAS BUT KEPT FOR NUECES AND KLEBERG COUNTIES. BOB HALL
PIER WILL BE CLOSE TO 2 FEET SO HAVE KEPT IT. EXPECTING LESS OF A
PROBLEM TOMORROW WITH LIGHTER WINDS AND DIMINISHED SWELLS.
FINALLY...DID NUDGE TEMPERATURES DOWN A BIT MAINLY AWAY FROM THE
COAST (AND STILL MAY BE A BIT HIGH). RAIN ENTERING AREA IS COOLING
THINGS A BIT AND CONTINUED CLOUD COVER WILL NOT BRING MUCH
INCREASE IN TEMPERATURES. STILL LIKE THE 20 POPS GOING AS STILL
ARE HAVING TROUBLE FINDING SOMEONE WITH MEASURABLE RAINFALL
(ALTHOUGH RADAR IS SHOWING SOME AREAS WITH MORE THAN 1/10 INCH
WHICH IS PLAUSIBLE GIVEN 45-55 DBZ CELLS AT TIMES. PRODUCTS OUT
AGAIN.
&&
.PREV DISCUSSION... /ISSUED 1137 AM CST TUE NOV 13 2012/
DISCUSSION...SEE 18Z AVIATION DISCUSSION.
AVIATION...VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD...WITH
SOME CIGS THROUGH THE PERIOD EXCEPT AT KVCT WHERE WILL SEE SOME
CLEARING WEDNESDAY BEFORE SUNRISE. SOME AREAS OF LIGHT TO MODERATE
RAINFALL SOUTH OF TERMINALS BETWEEN NOW AND 06Z...ENDING FROM WEST
TO EAST. MOST OF THE ACTIVITY SHOULD BE VERY LIGHT SO ONLY HAVE
PUT IN VCSH IN ALL BUT KVCT TERMINAL (NO VCSH). WILL UPDATE ON
THIS IF NEEDED...ESPECIALLY IF LIGHTNING BECOMES AN ISSUE AT
KLRD OR IF RAIN MORE MEASURABLE AND SCATTERED IN NATURE.
OTHERWISE...NE TO E WINDS TODAY 11 KNOTS OR LESS (BIT HIGHER AT
KCRP DUE TO PROXIMATE TO BAY). CIGS DECREASE A BIT THIS AFTERNOON
WITH APPROACH OF RAIN...THEN INCREASE OVERNIGHT WITH PASSAGE OF
JET AND DRIER AIR COMING IN FROM THE NORTHEAST.
PREV DISCUSSION... /ISSUED 949 AM CST TUE NOV 13 2012/
DISCUSSION...EXTENDED MEASURABLE RAINFALL MORE NORTH FOR
TODAY...BUT FOR NOW KEPT THE 20 POPS. BET PART OF RAIN CELL WENT
JUST SOUTH OF KCOT WHERE THEY GOT A TRACE OF RAIN (AREAS SOUTH
PROBABLY GOT A HUNDREDTH OR TWO). DID PUT THUNDER IN FOR THE
WESTERN AREAS SINCE IT HAS BEEN A BIT OBSERVED FROM TIME TO TIME
(PRETTY COOL ALOFT). OTHERWISE...MINOR CHANGES TO FIRST/SECOND
PERIODS.
MARINE...EXTENDED SCA FOR THE NEARSHORE TIL 3 PM. RUC13 AND NAM
IS KEEPING 20-25 KNOT WINDS OVER THE NORTHEASTERN NEARSHORE
THROUGH EARLY AFTERNOON...SO HAVE EXTENDED IT. LEFT SCA FOR
OFFSHORE AS-IS. DID MENTION RAIN FOR LATE AFTERNOON/TONIGHT BUT NO
THUNDER YET. WILL TAKE A LOOK AT LATER.
PREV DISCUSSION... /ISSUED 832 AM CST TUE NOV 13 2012/
DISCUSSION...BASED ON RADAR TRENDS AND 4 KM MODEL OUTPUT FROM SPC
AND TEX-TECH...HAVE DECIDED TO MENTION MEASURABLE RAINFALL IN THE
FORECAST. RADAR IS SHOWING SOME 40-50 DBZ ECHOES IN THE BRUSH
COUNTRY AND RIO GRANDE PLAINS HEADING TOWARD COTULLA. 4KM MODELS
SHOWING SOME QPF (ISOLATED OVER 1/4 INCH...AM NOT SURE IT WILL BE
THAT MUCH). THIS RAIN/SHOWERS IS FROM AN UPPER JET STREAK AND
SUFFICIENT MOISTURE. GIVEN THE FACT THAT PWATS GET ABOVE 1 INCH
LATER THIS AFTERNOON OVER THE SOUTHEAST...WILL GO WITH SOME LIGHT
RAIN AND PUT SPRINKLES FARTHER NORTH WHERE MOISTURE IS MORE
LIMITED. HAVE EVEN SEEN AN OCCASIONAL LIGHTNING STRIKE NW OF
COTULLA BUT THINK THAT OUR AREA WILL SEE ESSENTIALLY ALL RAIN OR
SPRINKLES AND THAT ELEVATED CONVECTION TOO LIMITED TO MENTION
THUNDER AT THIS TIME (HOWEVER WILL MONITOR). PRODUCTS ARE OUT.
PREV DISCUSSION... /ISSUED 537 AM CST TUE NOV 13 2012/
DISCUSSION...UPDATED FOR 12Z AVIATION.
AVIATION...BROKEN/OVERCAST CEILINGS BETWEEN 8K AND 10K FEET ARE
ANTICIPATED THROUGH THE MAJORITY OF THE TAF CYCLE. WINDS WILL
GENERALLY BE LESS THAN 10 KNOTS...WITH A NORTHEASTERLY COMPONENT.
LOW CONFIDENCE ON LIGHT RAIN/SPRINKLES LATER TODAY WILL PRECLUDE A
MENTION IN THE TAFS ATTM. VFR FORECAST CONTINUES THE NEXT 24
HOURS.
PREV DISCUSSION... /ISSUED 438 AM CST TUE NOV 13 2012/
SHORT TERM (TODAY THROUGH WEDNESDAY)...MORNING SATELLITE IMAGERY
HAS STREAM OF MID AND LEVEL HIGH CLOUDS MOVING ACROSS SOUTH TEXAS.
TEMPERATURES CURRENTLY ARE IN THE 40S AND 50 THIS MORNING AND DO
NOT THINK TEMPS WILL FALL TOO MUCH MORE. WEAK SHORTWAVE/UPPER JET
APPROACHES THE AREA TODAY...KEEPING MOSTLY CLOUDY CONDITIONS
ACROSS SOUTH TEXAS. WITH NORTHEAST WINDS CONTINUING...TEMPS WILL
ONLY CLIMB INTO THE 60S THIS AFTERNOON IN MOST LOCATIONS. DESPITE
WEAK ISENTROPIC LIFT OVER THE AREA TODAY...THINK MEASURABLE PRECIP
MAY BE DIFFICULT TO COME BY. ALSO...06Z MAV POPS HAVE COME IN
LOWER THAN 00Z GUIDANCE AS WELL. PREFER TO CONTINUE WITH THE
MENTION OF SPRINKLES INSTEAD OF LOW END POPS. UPPER DISTURBANCE TO
PASS EAST OF THE AREA TODAY...WITH DRY NORTHWEST FLOW OVER THE
REGION ON WEDNESDAY. SOME CLOUD COVER MAY LINGER INTO WEDNESDAY...
BUT TEMPS SHOULD REBOUND A FEW DEGREES WITH UPPER 60S TO LOWER 70S
FOR HIGHS. ALSO OF NOTE...MODERATE TO STRONG NORTHEAST WINDS WILL
PERSIST TODAY OVER THE GULF WATERS. WITH SEAS STILL RUNNING 7 TO 9
FEET AND TIDE LEVEL RUNNING SLIGHTLY ABOVE PREDICTED...MINOR TIDAL
OVERFLOW MAY OCCUR AT HIGH TIDE ALONG GULF BEACHES TODAY AND HAVE
ISSUED A COASTAL FLOOD ADVISORY.
MARINE...STRONG OFFSHORE FLOW WILL PERSIST OVER THE GULF WATERS
THIS MORNING...WITH SCA CONDITIONS OVER THE NEAR AND OFFSHORE
WATERS. WINDS WILL SLOWLY DECREASE BY THIS AFTERNOON TO BELOW SCA
OVER THE NEAR SHORE WATERS...BUT SCA CONDITIONS WILL CONTINUE OVER
THE OFFSHORE WATERS THROUGH TONIGHT AS SEAS REMAIN AROUND 7 FEET.
LONG TERM (WEDNESDAY NIGHT THROUGH MONDAY)...SLIGHTLY WARMER TEMPS
CAN BE EXPECTED WED NIGHT AND THU AS THE AIRMASS BEGINS TO MODIFY.
THE SRN EXTENT OF THE SFC HIGH IS PROGD TO REMAIN DRAPED ACROSS S TX
THROUGH FRI RESULTING IN A GENERALLY LIGHT NE FLOW ACROSS THE AREA
AND A WEAK TO MOD FLOW OVER THE COASTAL WATERS. THE FLOW BEGINS TO
VEER TO THE E AND SE THRU THE WEEKEND AND THEN STRENGTHENS MON/TUE
IN RESPONSE TO A LOW PRESSURE SYSTEM MOVG ACROSS THE CENTRAL PLAINS.
THE ONSHORE FLOW WILL CONTINUE THE WARMING TREND INTO THE WEEKEND
WITH HIGHS APPROACHING THE UPPER 70S TO LOW 80S BY SUNDAY. HAVE
KNOCKED THE FCSTD TEMPS DOWN A COUPLE OF DEGREES SAT/SUN DUE TO
PERSISTENT CLOUDS AND THE WINDS BLOWING ACROSS THE COOLER WATERS.
WEAK ISENTROPIC UPGLIDE IS PROGD TO DVLP ACROSS THE RIO GRANDE
PLAINS FRI WITH DEEPER MOISTURE SURGING NWD ALONG THE RIO GRANDE.
THIS WILL COMBINE WITH AN EMBEDDED SHORT WAVE ALOFT TO BRING A
SLIGHT CHC OF -SHRA`S TO THE RIO GRANDE PLAINS. KEPT THE SLIGHT CHC
ACROSS THE SRN COASTAL BEND AS WELL DUE TO SLIGHTLY DEEPER MOISTURE
AND THE SHORT WAVE ALTHOUGH ISENTROPIC DOWNGLIDE MAY PRECLUDE RAIN
FARTHER E. SATURDAY IS PROGD TO BE A TAD DRIER...THEN ANOTHER SURGE
OF MOISTURE MOVES INTO S TX ON SUN/MON TIME FRAME ALONG WITH A
SERIES OF WEAK SHORT WAVES. THE GFS WAS PREVIOUSLY SHOWING DEEPER
MOISTURE WITH BETTER DYNAMICS ON SUNDAY BUT THE LATEST RUN HAS
PUSHED IT BACK INTO MON. DECIDED TO KEEP A BROAD BRUSHED SLIGHT CHC
FOR BOTH DAYS FOR NOW.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 65 52 71 53 73 / 20 20 10 10 10
VICTORIA 62 42 68 41 72 / 10 10 10 10 10
LAREDO 64 51 72 55 75 / 20 20 10 10 10
ALICE 63 48 71 48 75 / 20 20 10 10 10
ROCKPORT 63 52 69 57 73 / 10 20 10 10 10
COTULLA 60 45 68 49 72 / 20 10 10 10 10
KINGSVILLE 66 49 71 52 75 / 20 20 10 10 10
NAVY CORPUS 66 55 70 56 72 / 20 20 10 10 10
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...HIGH RIP CURRENT RISK UNTIL MIDNIGHT CST TONIGHT FOR THE
FOLLOWING ZONES: ARANSAS...CALHOUN...KLEBERG...NUECES.
COASTAL FLOOD ADVISORY UNTIL 9 PM CST THIS EVENING FOR THE
FOLLOWING ZONES: KLEBERG...NUECES.
GM...SMALL CRAFT ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR THE
FOLLOWING ZONES: WATERS FROM BAFFIN BAY TO PORT ARANSAS
FROM 20 TO 60 NM...WATERS FROM PORT ARANSAS TO MATAGORDA
SHIP CHANNEL FROM 20 TO 60 NM.
SMALL CRAFT ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR THE
FOLLOWING ZONES: COASTAL WATERS FROM BAFFIN BAY TO PORT
ARANSAS OUT 20 NM...COASTAL WATERS FROM PORT ARANSAS TO
MATAGORDA SHIP CHANNEL OUT 20 NM.
&&
$$
GW/86...SHORT TERM
JM/75...LONG TERM
AREA FORECAST DISCUSSION...UPDATED
NWS CORPUS CHRISTI TX
1137 AM CST TUE NOV 13 2012
.DISCUSSION...SEE 18Z AVIATION DISCUSSION.
&&
.AVIATION...VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD...WITH
SOME CIGS THROUGH THE PERIOD EXCEPT AT KVCT WHERE WILL SEE SOME
CLEARING WEDNESDAY BEFORE SUNRISE. SOME AREAS OF LIGHT TO MODERATE
RAINFALL SOUTH OF TERMINALS BETWEEN NOW AND 06Z...ENDING FROM WEST
TO EAST. MOST OF THE ACTIVITY SHOULD BE VERY LIGHT SO ONLY HAVE
PUT IN VCSH IN ALL BUT KVCT TERMINAL (NO VCSH). WILL UPDATE ON
THIS IF NEEDED...ESPECIALLY IF LIGHTNING BECOMES AN ISSUE AT
KLRD OR IF RAIN MORE MEASURABLE AND SCATTERED IN NATURE.
OTHERWISE...NE TO E WINDS TODAY 11 KNOTS OR LESS (BIT HIGHER AT
KCRP DUE TO PROXIMATE TO BAY). CIGS DECREASE A BIT THIS AFTERNOON
WITH APPROACH OF RAIN...THEN INCREASE OVERNIGHT WITH PASSAGE OF
JET AND DRIER AIR COMING IN FROM THE NORTHEAST.
&&
.PREV DISCUSSION... /ISSUED 949 AM CST TUE NOV 13 2012/
DISCUSSION...EXTENDED MEASURABLE RAINFALL MORE NORTH FOR
TODAY...BUT FOR NOW KEPT THE 20 POPS. BET PART OF RAIN CELL WENT
JUST SOUTH OF KCOT WHERE THEY GOT A TRACE OF RAIN (AREAS SOUTH
PROBABLY GOT A HUNDREDTH OR TWO). DID PUT THUNDER IN FOR THE
WESTERN AREAS SINCE IT HAS BEEN A BIT OBSERVED FROM TIME TO TIME
(PRETTY COOL ALOFT). OTHERWISE...MINOR CHANGES TO FIRST/SECOND
PERIODS.
MARINE...EXTENDED SCA FOR THE NEARSHORE TIL 3 PM. RUC13 AND NAM
IS KEEPING 20-25 KNOT WINDS OVER THE NORTHEASTERN NEARSHORE
THROUGH EARLY AFTERNOON...SO HAVE EXTENDED IT. LEFT SCA FOR
OFFSHORE AS-IS. DID MENTION RAIN FOR LATE AFTERNOON/TONIGHT BUT NO
THUNDER YET. WILL TAKE A LOOK AT LATER.
PREV DISCUSSION... /ISSUED 832 AM CST TUE NOV 13 2012/
DISCUSSION...BASED ON RADAR TRENDS AND 4 KM MODEL OUTPUT FROM SPC
AND TEX-TECH...HAVE DECIDED TO MENTION MEASURABLE RAINFALL IN THE
FORECAST. RADAR IS SHOWING SOME 40-50 DBZ ECHOES IN THE BRUSH
COUNTRY AND RIO GRANDE PLAINS HEADING TOWARD COTULLA. 4KM MODELS
SHOWING SOME QPF (ISOLATED OVER 1/4 INCH...AM NOT SURE IT WILL BE
THAT MUCH). THIS RAIN/SHOWERS IS FROM AN UPPER JET STREAK AND
SUFFICIENT MOISTURE. GIVEN THE FACT THAT PWATS GET ABOVE 1 INCH
LATER THIS AFTERNOON OVER THE SOUTHEAST...WILL GO WITH SOME LIGHT
RAIN AND PUT SPRINKLES FARTHER NORTH WHERE MOISTURE IS MORE
LIMITED. HAVE EVEN SEEN AN OCCASIONAL LIGHTNING STRIKE NW OF
COTULLA BUT THINK THAT OUR AREA WILL SEE ESSENTIALLY ALL RAIN OR
SPRINKLES AND THAT ELEVATED CONVECTION TOO LIMITED TO MENTION
THUNDER AT THIS TIME (HOWEVER WILL MONITOR). PRODUCTS ARE OUT.
PREV DISCUSSION... /ISSUED 537 AM CST TUE NOV 13 2012/
DISCUSSION...UPDATED FOR 12Z AVIATION.
AVIATION...BROKEN/OVERCAST CEILINGS BETWEEN 8K AND 10K FEET ARE
ANTICIPATED THROUGH THE MAJORITY OF THE TAF CYCLE. WINDS WILL
GENERALLY BE LESS THAN 10 KNOTS...WITH A NORTHEASTERLY COMPONENT.
LOW CONFIDENCE ON LIGHT RAIN/SPRINKLES LATER TODAY WILL PRECLUDE A
MENTION IN THE TAFS ATTM. VFR FORECAST CONTINUES THE NEXT 24
HOURS.
PREV DISCUSSION... /ISSUED 438 AM CST TUE NOV 13 2012/
SHORT TERM (TODAY THROUGH WEDNESDAY)...MORNING SATELLITE IMAGERY
HAS STREAM OF MID AND LEVEL HIGH CLOUDS MOVING ACROSS SOUTH TEXAS.
TEMPERATURES CURRENTLY ARE IN THE 40S AND 50 THIS MORNING AND DO
NOT THINK TEMPS WILL FALL TOO MUCH MORE. WEAK SHORTWAVE/UPPER JET
APPROACHES THE AREA TODAY...KEEPING MOSTLY CLOUDY CONDITIONS
ACROSS SOUTH TEXAS. WITH NORTHEAST WINDS CONTINUING...TEMPS WILL
ONLY CLIMB INTO THE 60S THIS AFTERNOON IN MOST LOCATIONS. DESPITE
WEAK ISENTROPIC LIFT OVER THE AREA TODAY...THINK MEASURABLE PRECIP
MAY BE DIFFICULT TO COME BY. ALSO...06Z MAV POPS HAVE COME IN
LOWER THAN 00Z GUIDANCE AS WELL. PREFER TO CONTINUE WITH THE
MENTION OF SPRINKLES INSTEAD OF LOW END POPS. UPPER DISTURBANCE TO
PASS EAST OF THE AREA TODAY...WITH DRY NORTHWEST FLOW OVER THE
REGION ON WEDNESDAY. SOME CLOUD COVER MAY LINGER INTO WEDNESDAY...
BUT TEMPS SHOULD REBOUND A FEW DEGREES WITH UPPER 60S TO LOWER 70S
FOR HIGHS. ALSO OF NOTE...MODERATE TO STRONG NORTHEAST WINDS WILL
PERSIST TODAY OVER THE GULF WATERS. WITH SEAS STILL RUNNING 7 TO 9
FEET AND TIDE LEVEL RUNNING SLIGHTLY ABOVE PREDICTED...MINOR TIDAL
OVERFLOW MAY OCCUR AT HIGH TIDE ALONG GULF BEACHES TODAY AND HAVE
ISSUED A COASTAL FLOOD ADVISORY.
MARINE...STRONG OFFSHORE FLOW WILL PERSIST OVER THE GULF WATERS
THIS MORNING...WITH SCA CONDITIONS OVER THE NEAR AND OFFSHORE
WATERS. WINDS WILL SLOWLY DECREASE BY THIS AFTERNOON TO BELOW SCA
OVER THE NEAR SHORE WATERS...BUT SCA CONDITIONS WILL CONTINUE OVER
THE OFFSHORE WATERS THROUGH TONIGHT AS SEAS REMAIN AROUND 7 FEET.
LONG TERM (WEDNESDAY NIGHT THROUGH MONDAY)...SLIGHTLY WARMER TEMPS
CAN BE EXPECTED WED NIGHT AND THU AS THE AIRMASS BEGINS TO MODIFY.
THE SRN EXTENT OF THE SFC HIGH IS PROGD TO REMAIN DRAPED ACROSS S TX
THROUGH FRI RESULTING IN A GENERALLY LIGHT NE FLOW ACROSS THE AREA
AND A WEAK TO MOD FLOW OVER THE COASTAL WATERS. THE FLOW BEGINS TO
VEER TO THE E AND SE THRU THE WEEKEND AND THEN STRENGTHENS MON/TUE
IN RESPONSE TO A LOW PRESSURE SYSTEM MOVG ACROSS THE CENTRAL PLAINS.
THE ONSHORE FLOW WILL CONTINUE THE WARMING TREND INTO THE WEEKEND
WITH HIGHS APPROACHING THE UPPER 70S TO LOW 80S BY SUNDAY. HAVE
KNOCKED THE FCSTD TEMPS DOWN A COUPLE OF DEGREES SAT/SUN DUE TO
PERSISTENT CLOUDS AND THE WINDS BLOWING ACROSS THE COOLER WATERS.
WEAK ISENTROPIC UPGLIDE IS PROGD TO DVLP ACROSS THE RIO GRANDE
PLAINS FRI WITH DEEPER MOISTURE SURGING NWD ALONG THE RIO GRANDE.
THIS WILL COMBINE WITH AN EMBEDDED SHORT WAVE ALOFT TO BRING A
SLIGHT CHC OF -SHRA`S TO THE RIO GRANDE PLAINS. KEPT THE SLIGHT CHC
ACROSS THE SRN COASTAL BEND AS WELL DUE TO SLIGHTLY DEEPER MOISTURE
AND THE SHORT WAVE ALTHOUGH ISENTROPIC DOWNGLIDE MAY PRECLUDE RAIN
FARTHER E. SATURDAY IS PROGD TO BE A TAD DRIER...THEN ANOTHER SURGE
OF MOISTURE MOVES INTO S TX ON SUN/MON TIME FRAME ALONG WITH A
SERIES OF WEAK SHORT WAVES. THE GFS WAS PREVIOUSLY SHOWING DEEPER
MOISTURE WITH BETTER DYNAMICS ON SUNDAY BUT THE LATEST RUN HAS
PUSHED IT BACK INTO MON. DECIDED TO KEEP A BROAD BRUSHED SLIGHT CHC
FOR BOTH DAYS FOR NOW.
&&
.PRELIMINARY POINT TEMPS/POPS...
CORPUS CHRISTI 65 52 71 53 73 / 20 20 10 10 10
VICTORIA 63 42 68 41 72 / 10 10 10 10 10
LAREDO 66 51 72 55 75 / 20 20 10 10 10
ALICE 65 48 71 48 75 / 20 20 10 10 10
ROCKPORT 65 52 69 57 73 / 10 20 10 10 10
COTULLA 63 45 68 49 72 / 20 10 10 10 10
KINGSVILLE 66 49 71 52 75 / 20 20 10 10 10
NAVY CORPUS 66 55 70 56 72 / 20 20 10 10 10
&&
.CRP WATCHES/WARNINGS/ADVISORIES...
TX...HIGH RIP CURRENT RISK THROUGH THIS EVENING FOR THE FOLLOWING
ZONES: ARANSAS...CALHOUN...KLEBERG...NUECES.
COASTAL FLOOD ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR THE
FOLLOWING ZONES: ARANSAS...CALHOUN...KLEBERG...NUECES.
GM...SMALL CRAFT ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR THE
FOLLOWING ZONES: WATERS FROM BAFFIN BAY TO PORT ARANSAS
FROM 20 TO 60 NM...WATERS FROM PORT ARANSAS TO MATAGORDA
SHIP CHANNEL FROM 20 TO 60 NM.
SMALL CRAFT ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR THE
FOLLOWING ZONES: COASTAL WATERS FROM BAFFIN BAY TO PORT
ARANSAS OUT 20 NM...COASTAL WATERS FROM PORT ARANSAS TO
MATAGORDA SHIP CHANNEL OUT 20 NM.
&&
$$
GW/86...SHORT TERM
JM/75...LONG TERM
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1258 PM EST TUE NOV 13 2012
.SYNOPSIS...
A STRONG COLD FRONT EXTENDED FROM NEW ENGLAND INTO THE NORTHERN
GULF OF MEXICO. THIS FRONT WILL MOVE OFFSHORE BY THIS EVENING WITH
HIGH PRESSURE COVERING THE EASTERN HALF OF THE COUNTRY ON
WEDNESDAY. ANOTHER LOW WILL DEVELOP ALONG THE OLD COLD FRONT ON
FRIDAY AND SATURDAY OFF THE SOUTHEAST COAST.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1015 AM EST TUESDAY...
SATELLITE IMAGERY INDICATES A VERY SHARP GRADIENT TO THE CLOUD
COVER ACROSS THE PIEDMONTS THIS MORNING...WITH MOSTLY CLEAR SKIES
WEST OF A STOKES COUNTY NC TO AMHERST COUNTY VA LINE...WHILE
CLOUDY SKIES ARE OBSERVED TO THE EAST. THESE CLOUDS...AND THE
LINGERING SHOWER ACTIVITY WITHIN...ARE MAKING STEADY PROGRESS TO
THE EAST THIS MORNING...AND EXPECT THESE REMAINING CLOUDS TO BE
OUT OF OUR AREA DURING EARLY AFTERNOON. WITH COLDER AIR
CONTINUING TO BUILD IN WITH HIGH PRESSURE TO OUR WEST...AFTERNOON
TEMPERATURES WILL BE SIGNIFICANTLY LOWER THAN YESTERDAY...AND
EXPECT HIGHS FOR TODAY TO RANGE FROM THE LOW TO MID 40S ACROSS
THE MOUNTAINS...TO THE UPPER 40S ACROSS THE PIEDMONTS.
AS OF 445 AM EST TUESDAY...
AT 4AM COLD FRONT EXTENDED FROM VERMONT INTO SOUTHEAST VIRGINIA.
SURFACE DEW POINTS HAD DROPPED INTO THE 30S AND 40S ACROSS THE
COUNTY WARNING AREA. DRY AIR WILL CONTINUE TO WORK INTO THE REGION
SHORT WAVE AXIS CROSSING THROUGH THE OHIO VALLEY WILL LOWER 850
TEMPERATURES OVER THE MOUNTAINS TODAY AND WILL TURN SURFACE WINDS
TO THE NORTH TONIGHT.
00Z LOCAL WRF ALONG WITH THE LATEST RUC AND SREF GUIDANCE HELD
PRECIPITATION IN THE FAR SOUTHEAST COUNTY WARNING AREA THIS
MORNING...BUT ALL MODELS SHOWED DRY WEATHER AFTER 18Z/1PM.
NARROW BAND OF STRATUS IN THE WESTERN UPSLOPE AREA FROM WEST
VIRGINIA INTO TENNESSEE IS ALSO FORECAST TO DISSIPATE BY THIS
AFTERNOON.
WITH THE WEAK COLD AIR ADVECTION AND STARTING OUT WITH EXTENSIVE
CLOUD COVER THIS MORNING HAVE USED COOLER MAV GUIDANCE AS A
STARTING POINT FOR MAXIMUM TEMPERATURES TODAY.
HIGH PRESSURE BUILDS IN TONIGHT AND PRESSURE GRADIENT WEAKENS.
WITH A CLEAR SKY AND SURFACE DEW POINTS IN THE 20S AND
30S...AGAIN TRENDED TOWARD COLDER MAV GUIDANCE FOR OVERNIGHT LOWS.
&&
.SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/...
AS OF 310 AM EST TUESDAY...
THE FORECAST CHALLENGE DURING THIS PORTION OF THE FORECAST IS
CENTERED AROUND THE POTENTIAL IMPACTS OF A SHORTWAVE TROUGH MOVING
NORTH ALONG THE BACK SIDE OF A COLD FRONT ALONG THE ATLANTIC COAST.
THE ECMWF FOR A FEW DAYS NOW HAS HAD THE BOLDEST SOLUTION ON
BRINGING A SWATH OF PRECIPITATION THROUGH THE SOUTHEAST PORTION OF
THE FORECAST AREA LATE WEDNESDAY NIGHT...THURSDAY...AND EVEN EARLY
THURSDAY EVENING. THE NAM HAS HAD NOTHING TO DO WITH THIS SCENARIO.
UNTIL THE 12Z...7AM MONDAY SOLUTION...THE GFS KEPT ANY ASSOCIATED
PRECIPITATION SOUTHEAST OF THE REGION. AT THIS TIME...IT TOO HINTED
AT SOME PRECIPITATION SKIRTING THE SOUTHEAST PORTION OF THE FORECAST
AREA...BUT NOT TO THE DEGREE THE ECWMF SOLUTION DID.
THE 00Z...7PM MONDAY...SOLUTIONS HAVE SHOWN THE FOLLOWING TRENDS.
THE NAM STILL HAS NOTHING TO DO WITH PRECIPITATION REACHING THE
FORECAST AREA. THE GFS IS NOT AS IMPRESSIVE WITH ITS COVERAGE OF
PRECIPITATION AND IS PRIMARILY A THURSDAY EVENT NOW. THE ECMWF IS
STILL THE BOLDEST WITH THE PRECIPITATION...BUT IT HAS SHIFTED THE
PRECIPITATION MAXIMA SOUTHEAST...WITH VERY LITTLE OF IT SKIRTING THE
FAR SOUTHEAST PART OF THE FORECAST AREA.
TO KEEP A LEVEL OF CONSISTENCY...I DO NOT WANT TO MAKE TOO DRASTIC
OF A CHANGE TO THE FORECAST. HOWEVER...GIVEN THE TRENDS...THE
FORECAST WILL REFLECT A SLIGHTLY SMALLER CONFIDENCE IS PRECIPITATION
ACROSS THE SOUTHERN AND SOUTHEASTERN PORTIONS OF THE FORECAST AREA
LATE WEDNESDAY NIGHT THROUGH THURSDAY EVENING.
OTHERWISE...LITTLE CHANGES HAVE BEEN MADE TO THE REMAINDER OF THE
FORECAST DURING THIS TIME PERIOD. WE WILL STILL HAVE A DRY AND
COLDER WEDNESDAY WITH LIMITED CLOUD COVER HAS HIGH PRESSURE MOVES
INTO THE AREA BEHIND THE COLD FRONT.
FRIDAY WILL STILL BE REPRESENTED BY A DRY FORECAST...BUT WITH THE
APPROACH OF AN UPPER TROUGH...AND THE POTENTIAL FOR SOME MOIST NE
850 MB FLOW...HAVE CONTINUE TO REMAIN ON THE HIGH SIDE FOR CLOUD
COVER.
&&
.LONG TERM /SATURDAY THROUGH MONDAY/...
AS OF 353 PM EST MONDAY...
ALTHOUGH NOT AS PRONOUNCED AS THEIR ENSEMBLES...THE ECMWF AND TO A
LESSER DEGREE THE GFS...ARE FURTHER WEST WITH A REX BLOCK/CLOSED
UPPER LOW THAT FIRST PINCHES APART FROM THE UPPER FLOW ALONG THE
SOUTHERN GREAT LAKES FRIDAY. THE TRACK OF THE UPPER LOW DOES GO
AROUND OUR REGION...BUT THIS STILL MEANS AT LEAST A CHANCE OF
RAIN...NUMEROUS CLOUDS AND CHILLY AIR AROUND FOR MUCH OF THE
WEEKEND. FOLLOWING ITS BIAS...THE ECMWF MAY BE TOO FAR WEST WITH THE
TRACK OF THE LOW...HOWEVER EVEN THE OPERATIONAL GFS THROWS QPF
EAST OF THE BLUE RIDGE BY SUNDAY, THIS IS AT LEAST WORTH
MENTIONABLE POPS GREATER THAN 24 PERCENT IN THE FVX/LYH/DAN
CORRIDOR. OVER THE NEXT COUPLE OF DAYS OF MODEL RUNS...ITS
PROBABLY MORE LIKELY THAT THE RAIN SHIELD WILL END UP FURTHER WEST
INTO SW VA. IN THIS WEDGY REGIME WITH ENOUGH H85 RH...BOTH THE
ECMWF MOS AND THE MEX MOS LOOK SEVERAL DEGREES TOO WARM ON HIGHS
AND SEVERAL TOO COLD ON MINS. THEREFORE REDUCED THE DIURNAL RANGE
OF TEMPS...WITH SOME SPOTS STUCK IN THE 40S FOR MAX T BOTH
SATURDAY AND SUNDAY. STRUGGLING TO FIND ENOUGH COLD AIR FOR
SNOW...PERHAPS ENOUGH UPSLOPE COOLING LATE AT NIGHT FOR SOME SNOW
TO MIX IN ACROSS THE HIGHEST ELEVATIONS OF SE WEST VA OR NW NC.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
AS OF 1245 PM EST TUESDAY...
SHOWER ACTIVITY HAS ALL BUT EXITED THE AREA THIS AFTERNOON...WITH
THE LAST OF THE LOW CLOUD COVER EXPECTED TO EXIT FROM DAN AOA
13/19Z. ALL OTHER AIRPORTS ARE REPORTING CLEAR SKIES WITH A
NORTHWESTERLY WIND IN THE 5KT TO 10KT RANGE. EXPECT THESE VFR
CONDITIONS TO CONTINUE THROUGH THE REMAINDER OF THE 13/18Z TAF
PERIOD. DESPITE MOIST SOIL CONDITIONS FROM WIDESPREAD RAINFALL ON
MONDAY NIGHT/EARLY TUESDAY...DRY AIR BUILDING IN WITH HIGH
PRESSURE WILL PREVENT ALL BUT ISOLATED LIGHT FOG FROM DEVELOPING.
EXPECT WINDS TO GRADUALLY BECOME NORTHEASTERLY THROUGH THE EVENING
AS HIGH PRESSURE SLIDES EAST ACROSS THE LOWER GREAT LAKES.
HIGH PRESSURE WILL REMAIN OVER THE REGION THROUGH WEDNESDAY NIGHT
WITH VFR CONDITIONS. ANOTHER WEAK LOW PRESSURE SYSTEM OFF THE
SOUTHEAST COAST MAY BRING MVFR CIGS BACK TO THE REGION BY THURSDAY
MORNING. A MORE ORGANIZED LOW WILL DEVELOP OFF THE SOUTHEAST COAST
FRIDAY AND SATURDAY.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...NONE.
NC...NONE.
WV...NONE.
&&
$$
SYNOPSIS...AMS
NEAR TERM...AMS/NF
SHORT TERM...DS
LONG TERM...KM
AVIATION...AMS/NF
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
241 PM CST TUE NOV 13 2012
.SHORT TERM...THROUGH FRIDAY
241 PM CST TUE NOV 13 2012
MAIN FORECAST CONCERN REMAINS ON CLOUDS AND TEMPERATURES...ALONG
WITH SMALL PRECIPITATION POTENTIAL...WITH THE GENERALLY QUIET
WEATHER PATTERN IN PLACE NOW.
CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHTS SHOWED
NEARLY ZONAL FLOW ACROSS THE U.S....WITH A PERTURBATION IN THE FLOW
OVER WESTERN PORTIONS OF NEBRASKA AND KANSAS ASSOCIATED WITH A
SHORTWAVE TROUGH. ANOTHER WEAKER SHORTWAVE WAS NOTED OVER NORTH
DAKOTA. THE ZONAL FLOW HAS HELPED TO SPREAD WARMER AIR INTO THE
FORECAST AREA...REFLECTED BY THE 12Z MPX SOUNDING 850MB TEMP WHICH
CLIMBED FROM -13C AT 00Z TO -6C AT 12Z. EVEN WARMER AIR WAS PRESENT
TO THE WEST AT BIS AND ABR WHICH WERE AROUND -1C. THE COMBINATION OF
THIS WARMER AIR ALOFT...FULL SUNSHINE FOR MUCH OF THE DAY...AND DRY
AIR SHOWN TOO ON THE 12Z MPX SOUNDING HAS HELPED TEMPERATURES
REBOUND INTO THE 30S AFTER A CHILLY DAY YESTERDAY. SATELLITE IMAGERY
AND SURFACE OBS SHOWED A MASS OF MID AND HIGH CLOUDS SPREADING EAST
FROM THE DAKOTAS INTO MINNESOTA AND IOWA....DOWNSTREAM OF THE TWO
SHORTWAVES IN THE PLAINS. RADAR IMAGERY EVEN HAS SOME LIGHT DBZ
ECHOES BUT ARE ALL JUST VIRGA DUE TO DRY LOW LEVEL AIR IN PLACE. AT
THE SURFACE...A RIDGE OF HIGH PRESSURE EXTENDED FROM CHICAGO TO
NORTHEAST TEXAS WHILE A SURFACE TROUGH EXTENDED FROM NORTHWEST
ONTARIO TO PIERRE SOUTH DAKOTA.
TONIGHT AND WEDNESDAY...THE WEAK SHORTWAVE OVER NORTH DAKOTA IS
SLATED TO CROSS NORTHERN MINNESOTA AND INTO WESTERN LAKE SUPERIOR BY
12Z WEDNESDAY. GIVEN THE TRACK...BEST UPPER LEVEL PV ADVECTION STAYS
OFF TO OUR NORTH. WE DO HAVE A WARM ADVECTION PATTERN IN PLACE...AND
285-295K ISENTROPIC LIFT PLOTS REFLECT THAT. THE BEST ISENTROPIC
LIFT IS FORECAST TO OCCUR OVER THE FORECAST AREA...BUT THE LOWER
CONDENSATION PRESSURE DEFICITS ARE MOSTLY TO THE NORTH OF THE LIFT.
IF THERE IS ANY JUXTAPOSITION OF THE LIFT AND MOISTURE IS ALONG A
STRETCH BETWEEN RED WING AND TAYLOR COUNTY INTO NORTHEAST WISCONSIN.
MOST 13.12Z MODEL QPF OUTPUT FROM THE NAM...GFS AND ECMWF AS WELL AS
THE 13.15Z SREF MEAN SUGGEST A DRY FORECAST LIKE WE HAD GOING...BUT
THE 13.12Z GEM REGIONAL DOES HAVE LIGHT QPF. THINK THERE IS ENOUGH
SUGGESTION FROM THE MODELS TO HAVE AT LEAST A FLURRY MENTION.
NOTE...THOUGH...THERE IS A WARM LAYER AROUND 2000 FT WHICH COULD
MELT THE FLURRIES INTO SPRINKLES. WET-BULBING IS POSSIBLE...BUT
WOULD NOT BE APPROPRIATE GIVEN THE WEAK LIFT. MAY HAVE TO WATCH FOR
THE SPRINKLES TO FREEZE IF THE SURFACE TEMPERATURE CANNOT CLIMB
ABOVE FREEZING. OUTSIDE OF THIS VERY SMALL PRECIPITATION
POTENTIAL...THE MID AND HIGH CLOUDS SEEN OVER THE DAKOTAS WILL
SPREAD INTO THE AREA TONIGHT...THOUGH...WITH PARTIAL CLEARING
PROGGED TO OCCUR WEST TO EAST DURING THE DAY WEDNESDAY IN THE WAKE
OF THE SHORTWAVE. EXPECT WARMER TEMPERATURES TONIGHT THANKS TO THE
CLOUDS...BUT THE SLIGHTLY LATER ARRIVAL FOR THEM IN WISCONSIN COULD
ALLOW THE TYPICAL COLD SPOTS TO DROP INTO THE MID 20S BEFORE
CLIMBING. MOST OTHER LOCATIONS SHOULD BE NEAR 30 FOR LOWS. WARMER
850MB TEMPS ON WEDNESDAY OF 0-2C COMBINED WITH SOME SUNSHINE SHOULD
YIELD WARMER HIGHS AS WELL. A BLEND OF GUIDANCE SEEMED
REASONABLE...YIELDING MID 40S TO LOW 50S.
WEDNESDAY NIGHT AND THURSDAY...MODELS DEPICT A POTENT SHORTWAVE
TROUGH...CURRENTLY NEAR THE ALASKA/YUKON BORDER...TO DROP DOWN INTO
SASKATCHEWAN AND MANITOBA BY LATE WEDNESDAY. THIS POTENT SHORTWAVE
HEADS UP INTO HUDSON BAY BY LATE THURSDAY. ALTHOUGH THE SHORTWAVE IS
FAR FROM US...THERE IS A WEAKER SOUTHERN EXTENSION OF THE SHORTWAVE
THAT DROPS SOUTHEAST THROUGH THE AREA ON THURSDAY. A WEAK COLD FRONT
LOOKS TO ACCOMPANY THIS SHORTWAVE AT THE SURFACE. SIMILAR TO THE
SHORTWAVE CROSSING NORTH DAKOTA TONIGHT...THERE IS A WARM ADVECTION
PATTERN IN PLACE WITH AN AREA OF MID AND HIGH CLOUDS LIKELY TO
SPREAD ACROSS AHEAD OF THE SHORTWAVE. HOWEVER...ISENTROPIC LIFT
FIELDS THIS TIME DO NOT DEPICT ANY LIFT. IN ADDITION...THE SUB-CLOUD
LAYER REMAINS DRY ACCORDING TO FORECAST SOUNDINGS. THUS...THE DRY
FORECAST REMAINS. ALSO SIMILAR TO TONIGHT...THERE IS A PERIOD OF
PARTIAL CLEARING WEDNESDAY EVENING BEFORE MORE EXTENSIVE CLOUDS COME
IN TO ALLOW TEMPERATURES TO DROP OFF. THUS...SOME SITES IN WESTERN
WISCONSIN AGAIN COULD DIP INTO THE UPPER 20S BEFORE CLIMBING WITH
THE CLOUD INCREASE. LOWER TO MID 30S LOWS SHOULD BE TYPICAL
ELSEWHERE. SOME AFTERNOON SUN ON THURSDAY COMBINED WITH 850MB TEMPS
AGAIN IN THE 0-2C RANGE SHOULD ALLOW FOR HIGHS AGAIN IN THE MID 40S
TO LOW 50S.
THURSDAY NIGHT AND FRIDAY...IN THE WAKE OF THE WEDNESDAY
NIGHT/THURSDAY SHORTWAVE TROUGH...GOOD MODEL AGREEMENT EXISTS OF
STRENGTHENING UPPER AND SURFACE RIDGING BUILDING INTO THE FORECAST
AREA. BY 12Z FRIDAY...MUCH OF THE AREA IS ENCOMPASSED BY A SURFACE
HIGH PRESSURE RIDGE. CLEARING SKIES AND SUBSIDENCE IN THE WAKE OF
THE SHORTWAVE TROUGH...COMBINED WITH DRY AIR NOTED BY PRECIPITABLE
WATER VALUES FALLING TO NEAR ONE THIRD OF AN INCH AND LIGHT WINDS
SHOULD SUPPORT GOOD RADIATIONAL COOLING CONDITIONS. THUS...STAYED
TOWARDS THE LOW END OF GUIDANCE...ESPECIALLY AT THE TYPICAL COLD
SPOTS IN WISCONSIN WHICH COULD DIP INTO THE LOWER 20S. SUNNY SKIES
ON FRIDAY COMBINED WITH DRY AIR AND 850MB TEMPS AROUND 0C SHOULD
LEAD TO A DECENT TEMPERATURE RISE. FOLLOWED A BLEND OF GUIDANCE WITH
HIGHS IN THE 40S WHICH SEEMED REASONABLE...WARMEST OVER THE SOUTHERN
HALF OF THE AREA WHERE SLIGHTLY WARMER 925MB TEMPS EXIST.
.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY
241 PM CST TUE NOV 13 2012
13.12Z ECMWF/GFS/CANADIAN AND GFS ENSEMBLES CONTINUE TO SHOW UPPER
AND SURFACE RIDGING PRETTY MUCH DOMINATING THE AREA THROUGH THE
WEEKEND. THIS IS AHEAD OF A DEEP EAST PACIFIC TROUGH AND SOME WEAK
SUBTROPICAL SHORTWAVES LIFTING OUT OF THE FOUR CORNERS REGION AND
INTO THE NORTHERN PLAINS. THIS SETUP SHOULD KEEP THE AREA DRY WITH
TEMPERATURES GRADUALLY WARMING AS THE SURFACE HIGH FROM FRIDAY JUST
SLOWLY SHIFTS EAST. 850MB TEMPS TOP OUT IN THE 2C EAST TO 4C WEST
RANGE FOR THE WEEKEND WHICH SHOULD RESULT IN HIGHS IN THE MID 40S TO
LOWER 50S. LOWS ARE A LITTLE TRICKY...ESPECIALLY OVER WISCONSIN
WHERE LIGHT WINDS AT NIGHT ASSOCIATED WITH THE SURFACE RIDGE AND
MOSTLY CLEAR SKIES COULD ALLOW FOR QUICK TEMPERATURE DROPS.
FOR EARLY NEXT WEEK....THERE ARE ISSUES BEGINNING TO SHOW UP WITH
THE HANDLING OF THAT DEEP EAST PACIFIC TROUGH. ALL MODELS HAVE THE
TROUGH MOVING INLAND ON MONDAY...BUT THE 13.06Z/12Z GFS DRIVE MUCH
OF IT INTO THE WESTERN U.S. AS A BROAD TROUGH. COMPARE THIS TO THE
13.00Z ECMWF AND 13.12Z CANADIAN WHICH ARE MORE LIFT A LOT UP INTO
CANADA WHICH RESULTS IN A ZONAL FLOW PATTERN FROM THE PACIFIC
NORTHWEST INTO THE NORTHERN PLAINS BY TUESDAY. INTERESTINGLY...THE
NEW 13.12Z ECMWF HAS TRENDED TOWARDS THE GFS SCENARIO. GIVEN THE
ECMWF TREND...HAVE LEANED A LITTLE MORE IN THE GFS/ECMWF DIRECTION.
THIS SCENARIO WILL BRING A LOW PRESSURE SYSTEM AT US FROM THE
PLAINS...WITH VARYING INTENSITY DEPENDING ON HOW MUCH OF THAT UPPER
TROUGH DIGS INTO THE PLAINS. GULF OF MEXICO MOISTURE SHOULD RETURN
AHEAD OF IT...THUS HAVE PRECIPITATION CHANCES IN FOR SOUTH OF I-90
MONDAY NIGHT AND AREA WIDE ON TUESDAY. THE GENERAL WARM AIRMASS
SHOULD KEEP THE TYPE AS RAIN. REGARDING TEMPS...850MB TEMPS HOLD IN
THE 2-4C RANGE...YIELDING HIGHS STILL IN THE MID 40S TO LOW 50S.
LOOKING AHEAD TO THANKSGIVING...WITH THE MODEL TREND ON THE EAST
PACIFIC TROUGH NOW DIGGING INTO THE PLAINS...POTENTIAL EXISTS FOR A
LOW PRESSURE SYSTEM TO BE HANGING AROUND THE AREA WEDNESDAY INTO
THURSDAY. SOME PRECIPITATION THUS LOOKS ON TAP...WITH EITHER RAIN OR
A RAIN AND SNOW MIX THE TYPE. STAY TUNED TO LATER FORECASTS AS
THINGS IRON THEMSELVES OUT.
&&
.AVIATION...THROUGH 18Z WEDNESDAY
1047 AM CST TUE NOV 13 2012
FOCUS IS ON A MID-LEVEL SHORTWAVE TROUGH MOVING ACROSS THE UPPER
MISSISSIPPI RIVER VALLEY REGION OVER THE NEXT 24 HOURS. CURRENTLY
THIS WAVE WAS PRODUCING VFR ALTOCUMULUS ACROSS THE DAKOTAS/NEBRASKA.
THERE WERE ALSO A FEW RADAR RETURNS OUT OF THESE CLOUDS BUT
APPEARS THE PRECIPITATION WAS EVAPORATING BELOW THE CLOUD BASE PER
SURFACE OBSERVATIONS. AS THIS WAVE MOVES TOWARD THE AREA THIS
EVENING...LOOK FOR AN INCREASE IN ALTOCUMULUS AT THE KRST/KLSE
AIRPORTS...BECOMING BROKEN-OVERCAST OVERNIGHT. CLOUDS BASES
EXPECTED TO REMAIN AOA 8KFT AT BOTH SITES. ALTOCUMULUS IS THEN
EXPECTED TO SCATTER OUT WEDNESDAY MORNING IN THE 13-15Z TIME
FRAME. OTHERWISE...LOOK FOR A LIGHT SOUTHERLY SURFACE WIND IN THE
8-10KT RANGE.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
241 PM CST TUE NOV 13 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...AJ
AVIATION...DAS