Forecast Discussions mentioning any of
"HRRR" "RR" "RUC13" "RUC" received at GSD on 03/03/12
AREA FORECAST DISCUSSION
NWS LITTLE ROCK AR
1203 PM CST THU MAR 1 2012
.AVIATION...DISCUSSION FOR 18Z TAFS
BREEZY SOUTHERLY WINDS WILL BE NOTED AT THE NRN SITES TODAY AND
THESE SAME SITES WILL BE THE MOST LIKELY TO SEE VICINITY SHOWERS
LATE TONIGHT AND TMRW MORNING. OTRW...DO EXPECT SOME LOW CLOUDS TO
MOVE IN FROM LA AS WAS SEEN LAST NIGHT DOWN THERE. HAVE HIT THE
LOW CLOUD POTENTIAL PRETTY HARD OVERNIGHT...BUT DID NOT INDICATE
IFR OR LIFR CIGS. IF NAM AND RUC FCST SOUNDINGS VERIFY...LIFR
CONDS LOOK LIKELY MOST EVERYWHERE TOWARD DAYBREAK AND FUTURE
ISSUANCES CAN ADDRESS THIS CONCERN AS THE CRITICAL TAF PD CLOSES
IN.
&&
.SHORT TERM...TODAY THROUGH SUNDAY
LIGHT WINDS AND DRY AIR IS IN PLACE ACROSS THE NATURAL STATE EARLY
THIS MORNING AS HIGH PRESSURE HAS SETTLED INTO THE REGION. THE FRONT
THAT BROUGHT THE PRECIP TO PORTIONS OF THE STATE ON WED IS LOCATED
JUST SE OF AR...WHERE SOME SHRA HAS DEVELOPED ACROSS CENTRAL MS AND
SERN LA. SKIES REMAINED CLEAR FOR MUCH OF AR...WITH THE EXCEPTION
BEING FAR SERN PORTIONS OF THE STATE WHERE CLOUDS REMAINED IN CLOSE
PROXIMITY TO THE FRONT.
HIGH PRESSURE WILL SLIDE TO THE EAST THIS AFTERNOON...WITH WINDS
RETURNING TO THE SOUTH. MOISTURE LEVELS WILL SLOWLY INCREASE THIS
AFTERNOON...BUT MUCH MORE SUBSTANTIAL MOISTURE SURGE WILL COME
OVERNIGHT TONIGHT AS A WARM FRONT LIFTS NORTH ACROSS THE STATE. THIS
IS IN RESPONSE TO DEVELOPING SFC LOW PRESSURE OVER THE PANHANDLES OF
OK/TX LIFTING NE INTO MO. HAVE MENTIONED CHANCE POPS FOR MAINLY SHRA
AND ISOLATED TSRA THU NIGHT INTO EARLY FRI MORNING AS THIS FRONT
LIFTS NORTH. FORCING MAY BE STRONG ENOUGH ALONG THE WARM FRONT NEAR
THE SFC LOW ACROSS NRN AND NWRN AR DURING THE OVERNIGHT HRS THAT
SOME ISOLATED STRONG TO SVR STORMS COULD DEVELOP...WITH LARGE HAIL
BEING THE MAIN THREAT.
AS THE SFC LOW CONTINUES TO LIFT NE DURING THE DAY ON FRI...UPPER
LEVEL TROUGH AXIS WILL BE SURGING SE ACROSS KS...GIVING THE TRAILING
COLD FRONT MORE SEWD MOMENTUM. BY MIDDAY FRI...THE FRONT WILL BE
DRAPED MAINLY FROM THE MO BOOT-HEEL SW INTO SWRN SECTIONS OF AR.
LATEST MODEL GUIDANCE IS SHOWING SOMEWHAT LIMITED UPPER LEVEL
FORCING AROUND MIDDAY WHERE THE POTENTIAL FOR WIDESPREAD SHRA/TSRA
ACTIVITY IS LOOKING MORE LIMITED ACROSS CENTRAL AND NRN SECTIONS OF
THE STATE WITH THE MAIN COLD FROPA. WILL CONTINUE WITH LOW END
CHANCE POPS FOR THE MIDDAY TIME FRAME ALONG THE FRONT.
HOWEVER...SOLAR HEATING WILL HAVE GENERATED PLENTY OF INSTABILITY
ACROSS SERN SECTIONS OF THE STATE THAT MUCH BETTER CHANCES FOR
SHRA/TSRA WILL EXIST DURING THE LATE AFTERNOON AND EARLY EVENING HRS
WITH THE FROPA. HAVE GONE WITH LIKELY POPS ACROSS THE SERN COUNTIES
AS A RESULT. SOME STRONG TO SVR STORMS WILL BE POSSIBLE IN THIS
REGION OF THE CWA WITH PLENTY OF INSTABILITY AND SHR IN PLACE. THE
MAIN THREATS IN THIS CASE WOULD BE LARGE HAIL AND DAMAGING WINDS.
CANNOT RULE OUT AN ISOLATED TORNADO THREAT...BUT THE LOWEST LEVEL
WIND SHR...WHILE SIGNIFICANT...WOULD BE LESS SUPPORTIVE FOR
TORNADOES DUE TO SFC WINDS AHEAD OF THE FRONT BEING FROM THE SW. A
MORE SOUTHERLY OR EVEN EASTERLY SFC WIND COMPONENT WOULD BE MUCH
MORE FAVORABLE FOR A WIDESPREAD TORNADO THREAT...AND THIS SCENARIO
LOOKS UNLIKELY AT THIS TIME.
RELATIVELY QUIET WEEKEND IS IN STORE FOR AR AS THE MAIN LARGE SCALE
TROUGH AXIS SWINGS ACROSS THE STATE SAT INTO SUN. HIGH
PRESSURE...DRY AIR AND CLOSER TO NORMAL TEMPERATURES WILL BE THE
MAIN STORY DURING THE LAST TWO DAYS OF THE SHORT TERM.
LONG TERM...MONDAY THROUGH WEDNESDAY
STRONG HIGH PRESSURE WILL EXIT TOWARD THE SOUTHEAST UNITED STATES ON
MONDAY. CLOCKWISE FLOW AROUND THE HIGH WILL CREATE BREEZY SOUTHERLY
WINDS AND MILD TEMPERATURES. MOISTURE WILL ALSO SLOWLY INCREASE.
ON TUESDAY/WEDNESDAY...A STORM SYSTEM/FRONT WILL ATTEMPT TO APPROACH
FROM THE PLAINS. RIDGING TO THE EAST WILL SLOW THE PROGRESSION OF
THE FRONT. EVEN SO...INCREASED CLOUDS...AND HAVE CHANCES FOR SHOWERS
AND THUNDERSTORMS AS THE FRONT NEARS. RAIN CHANCES SHOULD BE HIGHEST
IN NORTHERN/WESTERN ARKANSAS CLOSEST TO THE FRONT AND AWAY FROM THE
RIDGE.
&&
.PRELIMINARY POINT TEMPS/POPS...
BATESVILLE AR 72 56 77 38 / 0 40 30 10
CAMDEN AR 81 64 81 45 / 10 20 40 20
HARRISON AR 73 55 67 32 / 0 40 40 0
HOT SPRINGS AR 78 61 78 41 / 10 30 30 10
LITTLE ROCK AR 77 60 80 42 / 10 30 30 10
MONTICELLO AR 81 64 80 45 / 10 20 60 50
MOUNT IDA AR 78 61 76 39 / 10 20 30 0
MOUNTAIN HOME AR 74 54 71 34 / 0 40 40 0
NEWPORT AR 71 57 77 39 / 0 40 30 10
PINE BLUFF AR 78 61 80 43 / 10 30 40 20
RUSSELLVILLE AR 76 58 77 38 / 0 30 30 0
SEARCY AR 74 57 78 39 / 0 30 30 10
STUTTGART AR 75 60 79 42 / 10 30 40 20
&&
.LZK WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
AVIATION...63
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
341 PM MST THU MAR 1 2012
.SHORT TERM...MOIST NORTHWEST FLOW ALOFT CONTINUES ACROSS THE
REGION THROUGH FRIDAY. AFTER A BRIEF DECREASE IN MOUNTAIN
SNOW...WEB CAMS AS WELL AS RADAR SHOW THE SNOW HAS INCREASED
AGAIN. WATER VAPOR LOOPS SHOW SOME SORT OF SHORTWAVE MOVING INTO
WESTERN COLORADO WHICH MAY BE AIDING IN THE SNOW INCREASE. THE
MOUNTAIN WARNINGS AND ADVISORIES STILL WARRANTED THROUGH TONIGHT.
THOUGH THERE MAY BE A BIT OF A DECREASE AGAIN OVERNIGHT AS SHOWN
BY THE LATEST RUC AND HRR RUNS. AS FOR PLAINS... STILL A BIT OF A
TRICKY FORECAST THIS EVENING AS MOST MODELS NOT HANDLING THINGS
WELL IN THE SHORT TERM. AIRMASS STILL A BIT UNSTABLE AND LOCAL
ACARS SOUNDINGS HAVE SHOWN A DEEPENING UPSLOPE. EARLIER SNOWBAND
HAS HELPED TO MOISTEN THE LOWER LAYERS. RADAR SHOWING ECHOES ALONG
FOOTHILLS AND URBAN CORRIDOR AS FAR NORTH AS LARIMER COUNTY...WITH
MOST OF THE ACTIVITY OVER JEFFERSON AND DOUGLAS COUNTIES. SO MOST
AREAS IN AND NEAR URBAN CORRIDOR SHOULD SEE SNOW SOON. AS
TEMPERATURES GET COLDER THIS EVENING...SHOULD ALSO SEE SOME
ACCUMULATING SNOW. ADVISORY FOR SOUTHERN FOOTHILLS AND PORTIONS OF
URBAN CORRIDOR STILL LOOKING ON TRACK. SHOULD SEE SOME BREAK IN
THE SNOWFALL TOWARDS 06Z...BASED ON THOSE RUC AND HRR RUNS. NEXT
WAVE LOOKS TO MOVE INTO THE AREA SATURDAY MORNING WHICH SHOULD
INCREASE THE SNOWFALL ACROSS THE REGION. WARNING AND ADVISORIES
FOR THE MOUNTAINS CONTINUE THROUGH FRIDAY...LOOKS REASONABLE. AS
FOR PLAINS...BEST CHANCE FOR SNOW TO BE IN THE 10Z-16Z AS THE LIFT
COMBINES WITH NORTHERLY FLOW...WITH THE BEST AREA IN ZONES 36 AND
41. FLOW BECOMES NORTHWEST DURING THE AFTERNOON...WITH DRIER AIR
WORKING ACROSS THE AREA. SHOULD SEE A DECREASE IN SNOW BY THE
AFTERNOON. OVERALL...CURRENT SNOW AMOUNTS STILL LOOK ON TRACK.
.LONG TERM...BY FRIDAY EVENING PRECIP SHOULD BE ON THE DECLINE
BOTH IN THE MTNS AND ALONG THE PALMER DIVIDE WITH SUBSIDENCE ON
THE BACK SIDE OF THE PASSING UPPER TROUGH. HOWEVER WEST-NORTHWEST
MID-LEVEL FLOW SHOULD CONTINUE TO PRODUCE AREAS OF OROGRAPHIC
SNOWFALL ROUGHLY ALONG AND WEST OF THE CONTINENTAL DIVIDE THROUGH
SATURDAY EVENING. DO NOT SEE MUCH IF ANY NEW ACCUMULATION.
OTHERWISE THIS SAME FLOW WILL DRY THINGS IN THE LOWER ATMOSPHERE
EAST OF THE MTNS ON SATURDAY. HOWEVER PASSING MID-LEVEL MOISTURE
IS EXPECTED TO PRODUCE PARTLY TO MOSTLY CLOUDY SKIES FOR MUCH OF
THE DAY. CLOUDS NOT EXPECTED TO DELAY WARMUP WITH MAX TEMPS ON
THE PLAINS 8-14F WARMER THAN READINGS ON FRIDAY.
FOR SUNDAY AND BEYOND...UPPER RIDGE BUILDING OVER THE GREAT BASIN
MIGRATES SLOWLY EASTWARD OVER THE ROCKY MTN REGION WITH HIGHEST
HEIGHTS...WARMEST TEMPS ALOFT...OVER COLORADO MONDAY/MONDAY
NIGHT. COULD SEE MAX TEMPS AS MUCH AS 10DEG F ABOVE AVERAGE FOR
THE DATE. WINDS NOT MUCH OF A CONCERN SUNDAY-TUESDAY. THEN BY
MID-WEEK...MEDIUM RANGE MODELS SHOW THIS RIDGE MOVING EAST AND
THE NEXT POTENT UPPER AIR TROUGH MOVING OVER THE GREAT BASIN.
SHOULD THIS OCCUR COULD SEE SNOW CHANCES RETURNING TO THE HIGH
COUNTRY AND THE DEVELOPMENT OF STG/GUSTY SOUTH-SOUTHWESTERLY
WINDS BOTH MTNS AND PLAINS.
&&
.AVIATION...SNOW DEVELOPING AGAIN ACROSS DENVER AREA...SHOULD
PERSIST THROUGH MUCH OF THE EVENING. MVFR CONDITIONS SHOULD
PREVAIL THROUGH 03Z WITH A CHANCE FOR IFR IN HEAVIER SNOW BANDS.
SHOULD SEE CONDITIONS IMPROVE TO VFR AFTER 03Z...THOUGH CEILINGS
AROUND 5000 FEET AGL WILL PREVAIL. NEXT WAVE TO AFFECT AREA AROUND
10Z WITH MVFR CONDITIONS REDEVELOPING AS SNOW SPREADS BACK INTO
REGION. DRIER AIR TO MOVE INTO THE AREA AFTER 16Z AS WINDS BECOME
NORTHWEST. VFR TO PREVAIL THROUGH THE AFTERNOON.
&&
.BOU WATCHES/WARNINGS/ADVISORIES...
WINTER WEATHER ADVISORY UNTIL 11 AM MST FRIDAY FOR COZ033-034.
WINTER STORM WARNING UNTIL 11 AM MST FRIDAY FOR COZ031.
&&
$$
SHORT TERM...D-L
LONG TERM....BAKER
AVIATION...D-L
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1000 PM EST FRI MAR 2 2012
.SYNOPSIS...
STRONG LOW PRESSURE MOVES THROUGH THE GREAT LAKES TONIGHT. THIS
WILL PUSH MILDER AIR INTO NEW ENGLAND OVERNIGHT AND SATURDAY
MORNING. THE LOW THEN SWINGS A COLD FRONT THROUGH NEW ENGLAND
AROUND MIDDAY SATURDAY. LOW PRES OVER THE MARITIMES PROVIDES
MAINLY DRY AND COLDER WEATHER SUN AND MON...THEN HIGH PRES MOVES
OFFSHORE YIELDING A SIGNIFICANT WARMING TREND MID TO LATE NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
10 PM UPDATE...ADJUSTED TEMPERATURE TRENDS TO REFLECT LATEST
OBSERVATIONS.
PREVIOUS DISCUSSION...
HAVE EXTENDED THE WINTER WEATHER ADVISORY ALONG THE
EDGES A BIT TO INCLUDE INTERIOR ESSEX COUNTY IN NE MA...NW
PROVIDENCE COUNTY AND THE NORTHERN CT COUNTIES OF
HARTFORD...TOLLAND AND WINDHAM. WE BELIEVE THE RISK OF A FEW HOURS
OF MIXED PRECIPITATION IS SUFFICIENT TO WARRANT THE ADVISORY
EXPANSION BASED ON CURRENT OBS AND LATEST MODEL PROJECTIONS. FOR
INTERIOR ESSEX COUNTY...SHORT TERM MODELS CONSISTENT IN KEEPING 2M
TEMPS AT OR BELOW FREEZING FOR A FEW HOURS AFTER LIGHT
PRECIPITATION MOVES IN. FOR NORTHERN CT AND NW RI...CONFIDENCE IS
LOWER BUT HERE TOO TEMP/DEWPT READINGS AND SHORT TERM MODEL
PROJECTIONS...INCLUDING RUC AND HRRR...POINT TO 2 TO 3 HOURS OF
LIGHT SNOW/SLEET/FREEZING RAIN. WHEN IT COMES TO SLEET AND
FREEZING RAIN...VERY SMALL AMOUNTS WILL CAUSE UNTREATED SURFACES
TO QUICKLY BECOME VERY SLIPPERY. RADAR AND BUFKIT PROFILES SUGGEST
A RISK OF A SEEDER-FEEDER MECHANISM SETTING UP LATER THIS
EVENING...SOONER THAN LATER FOR NORTHERN CT AND NW RI. THUS...
OPTED TO START THE ADVISORY AT 9 PM FOR THIS AREA.
INTERESTINGLY...A SMALL MESOSCALE AREA OF PATCHY VERY LIGHT SNOW
HAS ALREADY BROKEN OUT ALONG THE CT RIVER VALLEY...POSSIBLY A
COMBINATION OF TERRAIN INDUCED CONVERGENCE AND THE BEGINNING OF
SEEDING FROM ABOVE.
WARM ADVECTION AHEAD OF THE MIDWEST SYSTEM BRINGS INCREASING
ISENTROPIC LIFT OVERNIGHT. THE MAIN AREA OF LIFT ENTERS WESTERN
CT/MA AROUND MIDNIGHT AND IS CENTERED OVER SOUTHERN NEW ENGLAND
AROUND SUNRISE. LIFT RATES REACH A MAXIMUM AROUND 25 MB/HOUR AT
12Z.
PTYPE STARTS MESSY. ECMWF AND GFS SHOW STRONG LOW LEVEL NORTHERLY
AGEOSTROPHIC FLOW AT 06Z...WHICH WOULD HOLD IN COLD AIR NEAR THE
SURFACE. OBSERVED TEMPS ACROSS NORTHERN MASS AND SOUTHERN NH ARE
STARTING BELOW FREEZING. AREAS ALONG THE MASS PIKE AND IN NORTHERN
CT/NW RHODE ISLAND ARE MARGINAL. LOOKS LIKE MOSTLY RAIN IN THE
COASTAL PLAIN...ALTHOUGH BRIEF SLEET POSSIBLE AT THE START. THE
BEST CHANCE OF SNOW/SLEET/FREEZING RAIN WOULD BE IN WESTERN
MASS/WORCESTER HILLS/SOUTHERN NH. AN INCH OR SO OF SNOW IS
POSSIBLE IN THIS AREA AS WELL AS ICE OF UP TO 0.1 INCH.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
STRONG LIFT IN THE MORNING DECREASING TOWARD MIDDAY. COLD FRONT
MOVES ACROSS FROM WEST TO EAST LATE MORNING/MIDDAY WITH A WIND
SHIFT TO WEST FOR THE AFTERNOON. THIS WOULD MEAN A WET MORNING
WITH RAIN BECOMING MORE SHOWERY AS THE COLD FRONT APPROACHES.
ELEVATED INSTABILITY WITH TOTALS REACHING 50-55 AND SHOWALTER
REACHING -1. THIS IS ENOUGH TO MENTION A CHANCE OF THUNDER.
INCREASING SOUTH FLOW WORKS TO THE SURFACE AND MOVES NORTH ACROSS
THE REGION. THIS WILL CHANGE ANY LINGERING FREEZING PCPN TO RAIN.
IT WILL ALSO TRANSPORT MILDER TEMPS INTO THE REGION. 950 MB TEMPS
REACH 10C IN THE COASTAL PLAIN AND 4C IN THE NORTHWEST. THIS WOULD
THIS WOULD SUPPORT MAX TEMPS IN THE UPPER 40S AND 50S.
ONCE THE COLD FRONT MOVES THROUGH...WINDS WILL SHIFT TO WEST
DURING THE AFTERNOON AND BRING DRIER AIR TO THE REGION. MODEL TIME
SECTIONS SHOW DRYING AT ALL LEVELS...SO EXPECT AFTERNOON/EVENING
CLEARING...THEN MOSTLY CLEAR AT NIGHT.
A WAVE DEVELOPS ALONG THE DEPARTING COLD FRONT SATURDAY
NIGHT...BUT THE UPPER FLOW FEATURES A PROGRESSIVE TROUGH WITH FLOW
TOWARD THE EAST OVER THE NORTHEAST...SO ANY OFFSHORE LOW SHOULD
STAY OUT TO SEA. ENOUGH INCREASE IN HIGH LEVEL MOISTURE SO THAT WE
COULD GET INCREASED CIRRUS DURING SATURDAY NIGHT.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGHLIGHTS...
* BOTH WINTER AND SPRING-LIKE TEMPS FEATURED THIS PERIOD
* MAINLY DRY WEATHER MUCH OF THE TIME
MODEL PREFERENCES AND SYNOPTIC OVERALL...
12Z MODELS IN VERY GOOD AGREEMENT EARLY THIS PERIOD ON THE LARGE
SCALE FLOW ACROSS THE CONUS WHICH FEATURES A BROAD TROUGH OVER THE
EASTERN STATES AND ASSOCIATED BELOW NORMAL HEIGHTS AND TEMPS. MAINLY
DRY WEATHER SHOULD PREVAIL SUN-MON AS LOW LEVEL BAROCLINIC
ZONE/STORM TRACK SHOULD STAY FAR ENOUGH OFFSHORE. THEN MODELS AGREE
ON EJECTING TROUGH AND ASSOCIATED COLD AIRMASS BEGINNING TUE AS
SUBTROPICAL RIDGE DEVELOPS OVER THE SW ATLC. MODELS THEN DIVERGE
MID TO LATE NEXT WEEK WITH THE GFS ON THE PROGRESSIVE/FAST EDGE OF
THE GUIDANCE WITH THE NEXT UPSTREAM TROUGH. CONVERSELY THE 12Z ECMWF
REMAINS ON THE SLOW SIDE OF THE GUID ENVELOPE WITH THE 12Z GEFS AND
00Z ECENS SOMEWHERE IN BETWEEN. THIS WOULD SUGGEST THE MILD TO WARM
WEATHER DEVELOPING DURING THE MIDDLE OF NEXT WEEK MAY LINGER LONGER
THAN THE 12Z GFS SUGGEST. THUS WE HAVE TRENDED WARMER /CLOSER TO 18Z
HPC GUIDANCE/ AND SLOWER WITH FROPA THAN THE 12Z GMOS FOR NEXT THU
AND FRI.
DAILY SENSIBLE WEATHER DETAILS...
SUN...MID LEVEL TROF MAY BACK SUFFICIENTLY FOR OFFSHORE FRONTAL
BOUNDARY AND SURFACE WAVE TO RETROGRADE ENOUGH FOR PRECIP SHIELD TO
GRAZE CAPE COD AND THE ISLANDS. COLUMN APPEARS COLD ENOUGH TO
SUPPORT SNOW WITH SUB-FREEZING WET BULB TEMPS. HOWEVER GIVEN ONLY
VERY LIGHT PRECIP IS EXPECTED MUCH OF THIS MAY BE VIRGA AND FALL AS
RAIN AS PRECIP INTENSITY WILL LIKELY BE TOO LIGHT FOR WET BULB TEMPS
TO BE REALIZED. ELSEWHERE DRY WEATHER WILL PREVAIL ALONG WITH AT
LEAST PARTIAL SUNSHINE AND SEASONABLE TEMPERATURES.
MON...MORE OF A WINTER-LIKE DAY WITH BELOW NORMAL TEMPS. DIFFICULT
TEMP FORECAST HERE WITH NAM AND GFS MUCH COLDER ALOFT THAN THE
ECMWF. 12Z GMOS OFFERS HIGHS IN THE 30S...WHICH SEEMS REASONABLE.
HOWEVER IF CLOUD COVER BECOMES EXTENSIVE WITH COLD POOL ALOFT AND
CYCLONIC FLOW HIGH TEMPS WILL BE COOLER.
TUE...WILL BE A TRANSITION DAY WITH TEMPS REBOUNDING TOWARD 40 AS
HIGH PRES MOVES SOUTH OF NEW ENGLAND AND RETURN FLOW BEGINS TO
MODIFY COLD AIRMASS OVER THE REGION.
WED...TEMPS CONTINUE TO CLIMB INTO THE 50S COURTESY OF SUBTROPICAL
RIDGE DEVELOPING OFFSHORE.
THU AND FRI...COULD MAKE A RUN AT 60F THU AND POSSIBLE FRI AS STRONG
LOW LEVEL WAA OCCURS AHEAD OF APPROACHING COLD FRONT. AS MENTIONED
ABOVE FAVORED THE 12Z GEFS AND 00Z ECENS AS THIS SERVES AS A GOOD
COMPROMISE BETWEEN THE FAST OP 12Z GFS AND SLOWER 12Z ECMWF.
&&
.AVIATION /03Z SATURDAY THROUGH WEDNESDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT
MODERATE...30 PERCENT TO 60 PERCENT
HIGH...GREATER THAN 60 PERCENT
TONIGHT...
ISOLATED IFR CEILINGS OVER THE WORCESTER HILLS...OTHERWISE MVFR
CEILINGS ALONG WITH PATCHY LIGHT SNOW IN THE LOWER AND MID CT RVR
VLY. HOWEVER MVFR CONDITIONS WILL TREND TOWARD IFR ALL TERMINALS
03Z-06Z AS MAIN PRECIP SHIELD OVERSPREADS SOUTHERN NEW ENGLAND
FROM WEST TO EAST. A WINTRY MIX OF PRECIP EXPECTED FROM NORTHERN
CT/NORTHWEST RI AND MOST OF INTERIOR MA /WEST OF I-495/ INTO
SOUTHWEST NH. PRECIP WILL BE LIGHT AND MIXED PRECIP WILL LIMIT
SNOWFALL TO A COATING UP TO 2 INCHES ACROSS INTERIOR MA INTO
SOUTHWEST NH. PRECIP WILL CHANGE TO ALL RAIN OVERNIGHT EXCEPT OVER
INTERIOR MA /RT-2 CORRIDOR/ INTO SOUTHWEST NH WHERE A WINTRY MIX
OF PRECIP WILL PERSIST ALL NIGHT. FORECAST CONFIDENCE IN TAFS IN
MODERATE TO HIGH ON OVERALL WEATHER THEME...BUT LOWER CONFIDENCE
ON EXACT TIMING.
SATURDAY...
SHOWERS AND IFR CONTINUE SATURDAY MORNING ESPECIALLY AS A LINE OF
SHOWERS MOVES ACROSS MID MORNING TO MIDDAY. THERE IS SOME
POTENTIAL FOR SCATTERED THUNDERSTORMS WITH THE SHOWERS. COLD FRONT
SWEEPS THROUGH AROUND MIDDAY OR EARLY AFTERNOON WITH A WIND SHIFT
TO WEST WINDS. PCPN ENDS AT THAT TIME WITH CONDITIONS IMPROVING TO
VFR FROM WEST TO EAST DURING THE AFTERNOON. HIGH CONFIDENCE ON
TREND...MODERATE CONFIDENCE ON TIMING.
SATURDAY NIGHT...
VFR. HIGH CLOUDS RETURN OVERNIGHT ESPECIALLY ALONG THE SOUTH
COAST. MODERATE TO HIGH CONFIDENCE.
KBOS TERMINAL...
MVFR CEILINGS THIS EVENING BUT TRENDING TOWARD IFR TOWARD 06Z AS
PRECIP SHIELD OVERSPREADS EASTERN MA. THE PCPN MAY START AS A MIX
OF RAIN/SNOW/SLEET BUT SHOULD QUICKLY CHANGE TO ALL RAIN. IFR/LIFR
CONDITIONS LATE TONIGHT THROUGH SATURDAY MORNING. A LINE OF
SHOWERS MOVES THROUGH AROUND MIDDAY...POSSIBLY ACCOMPANIED BY A
THUNDERSTORM...BUT HIGHER PROBABILITY OF TSTMS WILL BE SOUTH OVER
THE OCEAN. WINDS SHIFT TO WEST...THEN CONDITIONS IMPROVE TO VFR
DURING THE AFTERNOON. VFR SATURDAY NIGHT.
OUTLOOK...SUNDAY THROUGH WEDNESDAY...
SUNDAY AND MONDAY...
MARGINAL MVFR-VFR CIGS BOTH DAYS WITH LOWEST CIGS SUN OVER THE CAPE
AND ISLANDS THEN SHIFTING INLAND/HIGHER TERRAIN MON. MAINLY DRY
WEATHER BOTH DAYS. MODERATE TO HIGH CONFIDENCE.
TUESDAY AND WED...
HIGH CONFIDENCE FOR VFR BOTH DAYS AS HIGH PRES BUILDS OVER THE AREA.
DRY WEATHER EXPECTED. SW WINDS MAY BECOME GUSTY WED.
&&
.MARINE...
HIGH PRESSURE MOVES OFF TO THE EAST THIS EVENING BRINGING A
SOUTHEAST FLOW TO THE WATERS. LOW PRESSURE MOVING THROUGH THE
GREAT LAKES WILL BRING STRONG WINDS ALOFT WHICH WILL TRANSPORT
ENOUGH MOISTURE FOR RAIN. THE INCREASED PRESSURE GRADIENT WILL
ALSO SUPPORT SOME INCREASE IN WIND SPEEDS. SO LATER TONIGHT WINDS
WILL REACH 25-30 KNOTS...AND SEAS WILL BUILD WITH THE EXPOSED
WATERS AT 5 FEET OR HIGHER.
SMALL CRAFT ADVISORIES HAVE BEEN EITHER CONTINUED OR ISSUED FOR
ALL WATERS EXCEPT BOSTON HARBOR AND NARRAGANSETT BAY. WINDS FOR
THESE LATTER WATERS DON/T LOOK TO REACH 25 KNOTS...BUT LOW
CONFIDENCE ON THIS PART OF THE FORECAST.
A COLD FRONT SWEEPS ACROSS THE WATERS DURING THE AFTERNOON. WEST
WINDS WILL HOVER NEAR 20-25 KNOTS LATER SATURDAY AND SATURDAY
NIGHT. SEAS WILL PERSIST AT OR ABOVE 5 FEET MUCH OF THIS TIME.
OUTLOOK...SUNDAY THROUGH WEDNESDAY...
SUN...MAINLY DRY WEATHER WITH LOW PRES TRACKING WELL S AND E OF NEW
ENGLAND.
MON...N-NW WINDS MAY BECOME GUSTY MON NIGHT AS LOW PRES TRACKS SE OF
NEW ENGLAND. DRY WEATHER AND GOOD VSBY SHOULD PREVAIL.
TUE...QUIET WEATHER PREVAILS WITH GUSTY NNW WINDS POSSIBLE EARLY TUE
BUT LIKELY DIMINISHING AS HIGH PRES DRIFT INTO THE AREA.
WED...SW WINDS MAY BECOME GUSTY ESPECIALLY NEAR SHORE AS HIGH PRES
DRIFTS SEAWARD. DRY WEATHER AND GOOD VSBY SHOULD PREVAIL.
&&
.CLIMATE...
A PUBLIC INFORMATION STATEMENT WAS ISSUED AT 225 PM. THIS
STATEMENT GIVES A REVIEW OF DECEMBER-JANUARY-FEBRUARY CONDITIONS AT
OUR FOUR CLIMATE SITES...BOSTON-PROVIDENCE-HARTFORD-WORCESTER.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...WINTER WEATHER ADVISORY UNTIL 4 AM EST SATURDAY FOR CTZ002>004.
MA...WINTER WEATHER ADVISORY UNTIL 5 AM EST SATURDAY FOR MAZ009>012.
WINTER WEATHER ADVISORY UNTIL 7 AM EST SATURDAY FOR MAZ002>006-
008-026.
NH...WINTER WEATHER ADVISORY UNTIL 9 AM EST SATURDAY FOR NHZ011-012-
015.
RI...WINTER WEATHER ADVISORY UNTIL 4 AM EST SATURDAY FOR RIZ001.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST SATURDAY FOR ANZ231>234.
SMALL CRAFT ADVISORY UNTIL 6 AM EST SUNDAY FOR ANZ235-237.
SMALL CRAFT ADVISORY UNTIL 6 AM EST SUNDAY FOR ANZ250-254>256.
SMALL CRAFT ADVISORY UNTIL 4 AM EST SUNDAY FOR ANZ251.
&&
$$
SYNOPSIS...WTB/NOCERA
NEAR TERM...BELK/THOMPSON
SHORT TERM...WTB
LONG TERM...NOCERA
AVIATION...WTB/NOCERA
MARINE...WTB/NOCERA
CLIMATE...STAFF
AREA FORECAST DISCUSSION
NWS TAUNTON MA
723 PM EST FRI MAR 2 2012
.SYNOPSIS...
STRONG LOW PRESSURE MOVES THROUGH THE GREAT LAKES TONIGHT. THIS
WILL PUSH MILDER AIR INTO NEW ENGLAND OVERNIGHT AND SATURDAY
MORNING. THE LOW THEN SWINGS A COLD FRONT THROUGH NEW ENGLAND
AROUND MIDDAY SATURDAY. LOW PRES OVER THE MARITIMES PROVIDES
MAINLY DRY AND COLDER WEATHER SUN AND MON...THEN HIGH PRES MOVES
OFFSHORE YIELDING A SIGNIFICANT WARMING TREND MID TO LATE NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
715 PM UPDATE...HAVE EXTENDED THE WINTER WEATHER ADVISORY ALONG THE
EDGES A BIT TO INCLUDE INTERIOR ESSEX COUNTY IN NE MA...NW
PROVIDENCE COUNTY AND THE NORTHERN CT COUNTIES OF
HARTFORD...TOLLAND AND WINDHAM. WE BELIEVE THE RISK OF A FEW HOURS
OF MIXED PRECIPITATION IS SUFFICIENT TO WARRANT THE ADVISORY
EXPANSION BASED ON CURRENT OBS AND LATEST MODEL PROJECTIONS. FOR
INTERIOR ESSEX COUNTY...SHORT TERM MODELS CONSISTENT IN KEEPING 2M
TEMPS AT OR BELOW FREEZING FOR A FEW HOURS AFTER LIGHT
PRECIPITATION MOVES IN. FOR NORTHERN CT AND NW RI...CONFIDENCE IS
LOWER BUT HERE TOO TEMP/DEWPT READINGS AND SHORT TERM MODEL
PROJECTIONS...INCLUDING RUC AND HRR...POINT TO 2 TO 3 HOURS OF
LIGHT SNOW/SLEET/FREEZING RAIN. WHEN IT COMES TO SLEET AND
FREEZING RAIN...VERY SMALL AMOUNTS WILL CAUSE UNTREATED SURFACES
TO QUICKLY BECOME VERY SLIPPERY. RADAR AND BUFKIT PROFILES SUGGEST
A RISK OF A SEEDER FEEDER MECHANISM SETTING UP LATER THIS
EVENING...SOONER THAN LATER FOR NORTHERN CT AND NW RI. THUS...OPTED TO
START THE ADVISORY AT 9 PM FOR THIS AREA. INTERESTINGLY...A SMALL
MESOCALE AREA OF PATCHY VERY LIGHT SNOW HAS ALREADY BROKEN OUT
ALONG THE CT RIVER VALLEY...POSSIBLY A COMBINATION OF TERRAIN
INDUCED CONVERGENCE AND THE BEGINNING OF SEEDING FROM ABOVE.
WE HAVE NOTED TEMPS TO BE A BIT COOLER THAN GUIDANCE BUT NO MAJOR
CHANGES TO THE FORECAST NEEDED.
PRIOR DISCUSSION...
LOW CLOUDS LINGERED OVER SOUTHERN NEW ENGLAND THROUGH THE
AFTERNOON. WITH HIGH PRESSURE MOVING OFFSHORE AND SURFACE WINDS
TURNING SOUTHEAST...NO REASON TO EXPECT THE CLOUDS TO GO AWAY.
WARM ADVECTION AHEAD OF THE MIDWEST SYSTEM BRINGS INCREASING
ISENTROPIC LIFT OVERNIGHT. THE MAIN AREA OF LIFT ENTERS WESTERN
CT/MA AROUND MIDNIGHT AND IS CENTERED OVER SOUTHERN NEW ENGLAND
AROUND SUNRISE. LIFT RATES REACH A MAXIMUM AROUND 25 MB/HOUR AT
12Z. SO EXPECT INCREASING CHANCE OF PCPN OVERNIGHT...POSSIBLY
10 PM-MIDNIGHT IN THE CT VALLEY BUT GENERALLY AROUND MIDNIGHT OR A
LITTLE AFTER ELSEWHERE.
PTYPE STARTS MESSY. ECMWF AND GFS SHOW STRONG LOW LEVEL NORTHERLY
AGEOSTROPHIC FLOW AT 06Z...WHICH WOULD HOLD IN COLD AIR NEAR THE
SURFACE. OBSERVED TEMPS ACROSS NORTHERN MASS AND SOUTHERN NH ARE
STARTING BELOW FREEZING. AREAS ALONG THE MASS PIKE AND IN NORTHERN
CT/NW RHODE ISLAND ARE MARGINAL. LOOKS LIKE MOSTLY RAIN IN THE
COASTAL PLAIN...ALTHOUGH BRIEF SLEET POSSIBLE AT THE START. THE
BEST CHANCE OF SNOW/SLEET/FREEZING RAIN WOULD BE IN WESTERN
MASS/WORCESTER HILLS/SOUTHERN NH. AN INCH OR SO OF SNOW IS
POSSIBLE IN THIS AREA AS WELL AS ICE OF UP TO 0.1 INCH.
WE WILL ISSUE A WINTER WEATHER ADVISORY FOR THIS AREA. THE
ADVISORY WILL HAVE ENDING TIME STAGGERED FROM SOUTH TO NORTH.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
STRONG LIFT IN THE MORNING DECREASING TOWARD MIDDAY. COLD FRONT
MOVES ACROSS FROM WEST TO EAST LATE MORNING/MIDDAY WITH A WIND
SHIFT TO WEST FOR THE AFTERNOON. THIS WOULD MEAN A WET MORNING
WITH RAIN BECOMING MORE SHOWERY AS THE COLD FRONT APPROACHES.
ELEVATED INSTABILITY WITH TOTALS REACHING 50-55 AND SHOWALTER
REACHING -1. THIS IS ENOUGH TO MENTION A CHANCE OF THUNDER.
INCREASING SOUTH FLOW WORKS TO THE SURFACE AND MOVES NORTH ACROSS
THE REGION. THIS WILL CHANGE ANY LINGERING FREEZING PCPN TO RAIN.
IT WILL ALSO TRANSPORT MILDER TEMPS INTO THE REGION. 950 MB TEMPS
REACH 10C IN THE COASTAL PLAIN AND 4C IN THE NORTHWEST. THIS WOULD
THIS WOULD SUPPORT MAX TEMPS IN THE UPPER 40S AND 50S.
ONCE THE COLD FRONT MOVES THROUGH...WINDS WILL SHIFT TO WEST
DURING THE AFTERNOON AND BRING DRIER AIR TO THE REGION. MODEL TIME
SECTIONS SHOW DRYING AT ALL LEVELS...SO EXPECT AFTERNOON/EVENING
CLEARING...THEN MOSTLY CLEAR AT NIGHT.
A WAVE DEVELOPS ALONG THE DEPARTING COLD FRONT SATURDAY
NIGHT...BUT THE UPPER FLOW FEATURES A PROGRESSIVE TROUGH WITH FLOW
TOWARD THE EAST OVER THE NORTHEAST...SO ANY OFFSHORE LOW SHOULD
STAY OUT TO SEA. ENOUGH INCREASE IN HIGH LEVEL MOISTURE SO THAT WE
COULD GET INCREASED CIRRUS DURING SATURDAY NIGHT.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
HIGHLIGHTS...
* BOTH WINTER AND SPRING-LIKE TEMPS FEATURED THIS PERIOD
* MAINLY DRY WEATHER MUCH OF THE TIME
MODEL PREFERENCES AND SYNOPTIC OVERALL...
12Z MODELS IN VERY GOOD AGREEMENT EARLY THIS PERIOD ON THE LARGE
SCALE FLOW ACROSS THE CONUS WHICH FEATURES A BROAD TROUGH OVER THE
EASTERN STATES AND ASSOCIATED BELOW NORMAL HEIGHTS AND TEMPS. MAINLY
DRY WEATHER SHOULD PREVAIL SUN-MON AS LOW LEVEL BAROCLINIC
ZONE/STORM TRACK SHOULD STAY FAR ENOUGH OFFSHORE. THEN MODELS AGREE
ON EJECTING TROUGH AND ASSOCIATED COLD AIRMASS BEGINNING TUE AS
SUBTROPICAL RIDGE DEVELOPS OVER THE SW ATLC. MODELS THEN DIVERGE
MID TO LATE NEXT WEEK WITH THE GFS ON THE PROGRESSIVE/FAST EDGE OF
THE GUIDANCE WITH THE NEXT UPSTREAM TROUGH. CONVERSELY THE 12Z ECMWF
REMAINS ON THE SLOW SIDE OF THE GUID ENVELOPE WITH THE 12Z GEFS AND
00Z ECENS SOMEWHERE IN BETWEEN. THIS WOULD SUGGEST THE MILD TO WARM
WEATHER DEVELOPING DURING THE MIDDLE OF NEXT WEEK MAY LINGER LONGER
THAN THE 12Z GFS SUGGEST. THUS WE HAVE TRENDED WARMER /CLOSER TO 18Z
HPC GUIDANCE/ AND SLOWER WITH FROPA THAN THE 12Z GMOS FOR NXT THU
AND FRI.
DAILY SENSIBLE WEATHER DETAILS...
SUN...MID LEVEL TROF MAY BACK SUFFICIENTLY FOR OFSHR FRONTAL
BOUNDARY AND SURFACE WAVE TO RETROGRADE ENOUGH FOR PRECIP SHIELD TO
GRAZE CAPE COD AND THE ISLANDS. COLUMN APPEARS COLD ENOUGH TO
SUPPORT SNOW WITH SUB-FREEZING WET BULB TEMPS. HOWEVER GIVEN ONLY
VERY LIGHT PRECIP IS EXPECTED MUCH OF THIS MAY BE VIRGA AND FALL AS
RAIN AS PRECIP INTENSITY WILL LIKELY BE TOO LIGHT FOR WET BULB TEMPS
TO BE REALIZED. ELSEWHERE DRY WEATHER WILL PREVAIL ALONG WITH AT
LEAST PARTIAL SUNSHINE AND SEASONABLE TEMPERATURES.
MON...MORE OF A WINTER-LIKE DAY WITH BELOW NORMAL TEMPS. DIFFICULT
TEMP FORECAST HERE WITH NAM AND GFS MUCH COLDER ALOFT THAN THE
ECMWF. 12Z GMOS OFFERS HIGHS IN THE 30S...WHICH SEEMS REASONABLE.
HOWEVER IF CLOUD COVER BECOMES EXTENSIVE WITH COLD POOL ALOFT AND
CYCLONIC FLOW HIGH TEMPS WILL BE COOLER.
TUE...WILL BE A TRANSITION DAY WITH TEMPS REBOUNDING TOWARD 40 AS
HIGH PRES MOVES SOUTH OF NEW ENGLAND AND RETURN FLOW BEGINS TO
MODIFY COLD AIRMASS OVER THE REGION.
WED...TEMPS CONTINUE TO CLIMB INTO THE 50S COURTESY OF SUBTROPICAL
RIDGE DEVELOPING OFSHR.
THU AND FRI...COULD MAKE A RUN AT 60F THU AND POSSIBLE FRI AS STRONG
LOW LEVEL WAA OCCURS AHEAD OF APPROACHING COLD FRONT. AS MENTIONED
ABOVE FAVORED THE 12Z GEFS AND 00Z ECENS AS THIS SERVES AS A GOOD
COMPROMISE BETWEEN THE FAST OP 12Z GFS AND SLOWER 12Z ECMWF.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT
MODERATE...30 PERCENT TO 60 PERCENT
HIGH...GREATER THAN 60 PERCENT
TONIGHT...
ISOLATED IFR CEILINGS OVER THE WORCESTER HILLS...OTHERWISE MVFR
CEILINGS ALONG WITH PATCHY LIGHT SNOW IN THE LOWER AND MID CT RVR VLY.
HOWEVER MVFR CONDITIONS WILL TREND TOWARD IFR ALL TERMINALS 03Z-
06Z AS MAIN PRECIP SHIELD OVERSPREADS SOUTHERN NEW ENGLAND FROM
WEST TO EAST. A WINTRY MIX OF PRECIP EXPECTED FROM NORTHERN
CT/NORTHWEST RI AND MOST OF INTERIOR MA /WEST OF I-495/ INTO
SOUTHWEST NH. PRECIP WILL BE LIGHT AND MIXED PRECIP WILL LIMIT
SNOWFALL TO A COATING UP TO 2 INCHES ACROSS INTERIOR MA INTO
SOUTHWEST NH. PRECIP WILL CHANGE TO ALL RAIN OVERNIGHT EXCEPT
OVER INTERIOR MA /RT-2 CORRIDOR/ INTO SOUTHWEST NH WHERE A WINTRY
MIX OF PRECIP WILL PERSIST ALL NIGHT. FORECAST CONFIDENCE IN TAFS
IN MODERATE TO HIGH ON OVERAL WEATHER THEME...BUT LOWER CONFIDENCE
ON EXACT TIMING.
SATURDAY...
SHOWERS AND IFR CONTINUE SATURDAY MORNING ESPECIALLY AS A LINE OF
SHOWERS MOVES ACROSS MID MORNING TO MIDDAY. THERE IS SOME
POTENTIAL FOR SCATTERED THUNDERSTORMS WITH THE SHOWERS. COLD FRONT
SWEEPS THROUGH AROUND MIDDAY OR EARLY AFTERNOON WITH A WIND SHIFT
TO WEST WINDS. PCPN ENDS AT THAT TIME WITH CONDITIONS IMPROVING TO
VFR FROM WEST TO EAST DURING THE AFTERNOON. HIGH CONFIDENCE ON
TREND...MODERATE CONFIDENCE ON TIMING.
SATURDAY NIGHT...
VFR. HIGH CLOUDS RETURN OVERNIGHT ESPECIALLY ALONG THE SOUTH
COAST. MODERATE TO HIGH CONFIDENCE.
KBOS TERMINAL...
MVFR CEILINGS THIS EVENING BUT TRENDING TOWARD IFR TOWARD 06Z AS
PRECIP SHIELD OVERSPREADS EASTERN MA. THE PCPN MAY START AS A MIX
OF RAIN/SNOW/SLEET BUT SHOULD QUICKLY CHANGE TO ALL RAIN. IFR/LIFR
CONDITIONS LATE TONIGHT THROUGH SATURDAY MORNING. A LINE OF
SHOWERS MOVES THROUGH AROUND MIDDAY...POSSIBLY ACCOMPANIED BY A
THUNDERSTORM...BUT HIGHER PROBABILITY OF TSTMS WILL BE SOUTH OVER
THE OCEAN. WINDS SHIFT TO WEST...THEN CONDITIONS IMPROVE TO VFR
DURING THE AFTERNOON. VFR SATURDAY NIGHT.
OUTLOOK...SUNDAY THROUGH WEDNESDAY...
SUNDAY AND MONDAY...
MARGINAL MVFR-VFR CIGS BOTH DAYS WITH LOWEST CIGS SUN OVER THE CAPE
AND ISLANDS THEN SHIFTING INLAND/HIGHER TERRAIN MON. MAINLY DRY
WEATHER BOTH DAYS. MODERATE TO HIGH CONFIDENCE.
TUESDAY AND WED...
HIGH CONFIDENCE FOR VFR BOTH DAYS AS HIGH PRES BUILDS OVER THE AREA.
DRY WEATHER EXPECTED. SW WINDS MAY BECOME GUSTY WED.
&&
.MARINE...
HIGH PRESSURE MOVES OFF TO THE EAST THIS EVENING BRINGING A
SOUTHEAST FLOW TO THE WATERS. LOW PRESSURE MOVING THROUGH THE
GREAT LAKES WILL BRING STRONG WINDS ALOFT WHICH WILL TRANSPORT
ENOUGH MOISTURE FOR RAIN. THE INCREASED PRESSURE GRADIENT WILL
ALSO SUPPORT SOME INCREASE IN WIND SPEEDS. SO LATER TONIGHT WINDS
WILL REACH 25-30 KNOTS...AND SEAS WILL BUILD WITH THE EXPOSED
WATERS AT 5 FEET OR HIGHER.
SMALL CRAFT ADVISORIES HAVE BEEN EITHER CONTINUED OR ISSUED FOR
ALL WATERS EXCEPT BOSTON HARBOR AND NARRAGANSETT BAY. WINDS FOR
THESE LATTER WATERS DON/T LOOK TO REACH 25 KNOTS...BUT LOW
CONFIDENCE ON THIS PART OF THE FORECAST.
A COLD FRONT SWEEPS ACROSS THE WATERS DURING THE AFTERNOON. WEST
WINDS WILL HOVER NEAR 20-25 KNOTS LATER SATURDAY AND SATURDAY
NIGHT. SEAS WILL PERSIST AT OR ABOVE 5 FEET MUCH OF THIS TIME.
OUTLOOK...SUNDAY THROUGH WEDNESDAY...
SUN...MAINLY DRY WEATHER WITH LOW PRES TRACKING WELL S AND E OF NEW
ENGLAND.
MON...N-NW WINDS MAY BECOME GUSTY MON NIGHT AS LOW PRES TRACKS SE OF
NEW ENGLAND. DRY WEATHER AND GOOD VSBY SHOULD PREVAIL.
TUE...QUIET WEATHER PREVAILS WITH GUSTY NNW WINDS POSSIBLE EARLY TUE
BUT LIKELY DIMINISHING AS HIGH PRES DRIFT INTO THE AREA.
WED...SW WINDS MAY BECOME GUSTY ESPECIALLY NEAR SHORE AS HIGH PRES
DRIFTS SEAWARD. DRY WEATHER AND GOOD VSBY SHOULD PREVAIL.
&&
.CLIMATE...
A PUBLIC INFORMATION STATEMENT WAS ISSUED AT 225 PM. THIS
STATEMENT GIVES A REVIEW OF DECEMBER-JANUARY-FEBRUARY CONDITIONS AT
OUR FOUR CLIMATE SITES...BOSTON-PROVIDENCE-HARTFORD-WORCESTER.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...WINTER WEATHER ADVISORY UNTIL 4 AM EST SATURDAY FOR CTZ002>004.
MA...WINTER WEATHER ADVISORY UNTIL 5 AM EST SATURDAY FOR MAZ009>012.
WINTER WEATHER ADVISORY FROM 11 PM THIS EVENING TO 7 AM EST
SATURDAY FOR MAZ002>006-008-026.
NH...WINTER WEATHER ADVISORY FROM 11 PM THIS EVENING TO 9 AM EST
SATURDAY FOR NHZ011-012-015.
RI...WINTER WEATHER ADVISORY UNTIL 4 AM EST SATURDAY FOR RIZ001.
MARINE...SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM EST
SATURDAY FOR ANZ231>234.
SMALL CRAFT ADVISORY UNTIL 6 AM EST SUNDAY FOR ANZ235-237.
SMALL CRAFT ADVISORY UNTIL 6 AM EST SUNDAY FOR ANZ250-254>256.
SMALL CRAFT ADVISORY UNTIL 4 AM EST SUNDAY FOR ANZ251.
&&
$$
SYNOPSIS...WTB/NOCERA
NEAR TERM...WTB/THOMPSON
SHORT TERM...WTB
LONG TERM...NOCERA
AVIATION...WTB/NOCERA
MARINE...WTB/NOCERA
CLIMATE...
AREA FORECAST DISCUSSION
NWS TAUNTON MA
412 PM EST THU MAR 1 2012
.SYNOPSIS...
LOW PRESSURE RACING ACROSS NEW ENGLAND WILL MOVE OFF TO THE EAST
TONIGHT. HIGH PRESSURE WILL BRING DRY WEATHER OVERNIGHT AND
FRIDAY. STRONG LOW PRESSURE WILL MOVE THROUGH THE GREAT LAKES LATE
FRIDAY INTO FRIDAY NIGHT AND SWING A COLD FRONT THROUGH NEW
ENGLAND SATURDAY. MAINLY DRY AND COLDER WEATHER WILL FOLLOW EARLY
NEXT WEEK...THEN A SIGNIFICANT WARMING TREND IS POSSIBLE TOWARD
MIDDLE AND END OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
LIGHT SNOW ALONG AND NORTH OF THE MASS PIKE WITH VSBYS BELOW 1
MILE IN THE MERRIMACK VALLEY AND PARTS OF THE BOSTON METROWEST.
FARTHER SOUTH LIGHT MIXED RAIN/SNOW ACROSS CT-RI-SOUTHEAST MASS.
RADAR SHOWS THIS PCPN AREA EXTENDS WEST TO CENTRAL NY...SO IT
SHOULD TAKE SEVERAL HOURS FOR THE PCPN TO DIMINISH.
NORTHEAST WINDS LINGERED THROUGH EVENING IN EASTERN MASSACHUSETTS
BUT THE TREND SHOULD BE TOWARD A NORTH WIND ALL AREAS TONIGHT.
THIS WILL DRAW COLDER AIR IN AND SHOULD CONTRIBUTE TO CHANGING
PCPN OVER TO SNOW BEFORE IT ENDS.
UPPER SHORTWAVE OVER NY IS SUPPORTING THIS PCPN. THE SHORTWAVE
WILL CROSS NEW ENGLAND A FEW HOURS EITHER SIDE OF 00Z. ONCE IT
MOVES PAST...PCPN SHOULD TAPER OFF. WE HAVE MAINTAINED LIKELY TO
CATEGORICAL POPS ACROSS SRN NH/MUCH OF MASS/NORTHERN CT/NORTHERN
RI THIS EVENING WITH POPS THEN DIMINISHING OVERNIGHT.
TEMPS/DEWPOINTS ARE A BLEND OF HRRR AND MOS.
WITH ONGOING PCPN AND A FEW HEAVIER SPOTS ON RADAR...WE ARE
MAINTAINING EXISTING WINTER WEATHER HEADLINES THROUGH THE EVENING
RUSH HOUR. BUT WE EXPECT THEY WILL EITHER EXPIRE OR BE EXTENDED
FOR JUST A COUPLE OF ADDITIONAL HOURS.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
HIGH PRESSURE OVER THE MIDWEST MOVES OVER NEW ENGLAND FRIDAY
MORNING. WE EXPECT PARTIAL CLEARING...BUT LINGERING MOISTURE BELOW
850 MB SUGGESTS PARTLY TO MOSTLY CLOUDY SKIES DURING THE DAY.
MEANWHILE...INCREASING MOISTURE AT HIGH LEVELS IN THE WARM
ADVECTION AHEAD OF THE NEXT SYSTEM. SO EXPECT INCREASING HIGH
CLOUDS OVER THE TOP OF ANY LOW CLOUDS.
925 MB TEMPS OF -2C TO -4C SUPPORT MAX TEMPS IN THE MID 30S TO
AROUND 40. A BLEND OF MOS ACHIEVED THIS RANGE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
HIGHLIGHTS...
* MIXED PRECIP AND ICE INTERIOR FRI NIGHT CHANGING TO RAIN...THEN
SHOWERS AND MILD SAT
* MUCH COLDER WITH BELOW NORMAL TEMPS EARLY NEXT WEEK
* WARMING TREND WED INTO THU
FRI NIGHT...
MODELS IN AGREEMENT THAT STRONG LOW PRES WILL BE MOVING NE THROUGH
THE GT LAKES WITH WARM FRONT APPROACHING FROM THE S. WAA PRECIP
WILL BE OVERSPREADING SNE FRI EVENING AND CONTINUING THROUGH THE
NIGHT. SOUNDINGS AND PARTIAL THICKNESSES INDICATE ENOUGH COLD AIR
IN THE COLUMN TO SUPPORT A PERIOD OF SNOW THEN ICE IN THE DISTANT
INTERIOR BEFORE MILDER AIR GRADUALLY PUSHES NORTHWARD. DO NOT
EXPECT MUCH SNOW ACCUM AS MID LEVELS ARE WARMING QUICKLY...BUT AN
EXTENDED PERIOD OF FREEZING RAIN AND ICING IS POSSIBLE MAINLY N OF
I90 AND W OF I495 WHERE LOW LEVEL COLD AIR WILL BE SLOW TO SCOUR
OUT...AND WINTER WX ADVISORIES WILL LIKELY BE NEEDED. DO NOT EXPECT
SIGNIFICANT ICE ACCUM BUT UP TO A TENTH OF AN INCH OF ICE ACCRETION
IS POSSIBLE. EVEN ALONG THE COAST...THE RAIN MAY MIX WITH SLEET AT
THE ONSET. SLOWLY RISING TEMPS OVERNIGHT.
SATURDAY...
SHOWERS WILL CONTINUE INTO SAT AS WARM FRONT LIFTS NWD INTO
REGION...BUT FOCUS WILL GRADUALLY SHIFT TO THE COAST ASSOCD WITH
MODEST LOW LEVEL JET...THEN SHOWERS MOVE OFFSHORE DURING THE
AFTERNOON AS FRONT MOVES THROUGH. POPS WILL BE DECREASING FROM WEST
TO EAST DURING THE DAY. THERE IS STILL AN ELEVATED THUNDER
THREAT...MAINLY NEAR THE S COAST IN THE MORNING AS AREA OF SUBZERO
SWI AND MID 50S TT MOVE NWD. SFC INSTABILITY IS NIL AND LLJ IS NOT
AS ROBUST AND IS FURTHER OFFSHORE SO WIND THREAT IS MINIMAL. AS
WARM FRONT LIFTS NWD ACROSS THE COASTAL PLAIN...TEMPS WILL LIKELY
SPIKE WELL INTO THE 50S...ESPECIALLY RI AND SE MA...BUT TEMPS
PROBABLY HOLDING IN THE 40S N OF THE PIKE.
SUNDAY THROUGH TUESDAY...
MID LEVEL TROF WILL BE MOVING EAST INTO NEW ENG BRINGING A
NOTICEABLE COOLING TREND. STILL MILD SUNDAY...THEN COLDER WITH
BELOW NORMAL TEMPS MON AND TUE. IN FACT...MINS WILL LIKELY DROP
DOWN INTO THE SINGLE NUMBERS AND TEENS MON NIGHT. COASTAL STORMS
EXPECTED TO REMAIN OFFSHORE SUN AND MON...BUT SERIES OF SHORTWAVES
AND SFC TROFS MOVING INTO THE REGION MAY BRING A FEW RAIN/SNOW SUN
AND MON. MOSTLY SUNNY AND DRY WEATHER EXPECTED TUE AS SFC HIGH
BUILDS IN FROM THE WEST...BUT OCEAN EFFECT SNOW SHOWERS MAY AFFECT
THE OUTER CAPE.
WEDNESDAY AND THURSDAY...
GFS AND ECMWF INDICATE A SIGNIFICANT WARMING TREND AS HIGH PRES
MOVES S OF THE COAST WITH RETURN FLOW DEVELOPING. WED WILL BE THE
TRANSITION DAY AFTER A COLD START...THEN UNSEASONABLY MILD WEATHER
POSSIBLE BY THU AND ECMWF HAS THE POTENTIAL FOR TEMPS TO REACH THE
LOWER 60S. DID NOT GO QUITE THAT HIGH IN THE FORECAST AS THIS IS
STILL 7 DAYS AWAY.
&&
.AVIATION /21Z THURSDAY THROUGH TUESDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT
MODERATE...30 PERCENT TO 60 PERCENT
HIGH...GREATER THAN 60 PERCENT
THROUGH 00Z...
MIXED IFR AND MVFR CEILINGS/VSBYS IN RAIN AND SNOW. THESE
CONDITIONS SHOULD CONTINUE THROUGH 00Z. HIGH CONFIDENCE.
TONIGHT...
LEFTOVER MVFR/IFR CONDITIONS THROUGH 03Z ESPECIALLY BDL-PVD NORTH.
NORTH WINDS ALL AREAS. CONDITIONS SHOULD IMPROVE TO MVFR CEILINGS
AND UNRESTRICTED VSBYS OVERNIGHT. MODERATE CONFIDENCE.
FRIDAY...
CONDITIONS IMPROVE TO VFR FRIDAY MORNING. LIGHT WINDS SHIFT TO
SOUTHEAST BY AFTERNOON. HIGH CONFIDENCE.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF. IFR CONDITIONS IN RAIN
THIS MORNING CHANGING TO SNOW THIS AFTERNOON. AN ADDITIONAL INCH OR
TWO OF ACCUMULATION POSSIBLE...MAINLY ON NON PAVED SURFACES. GUSTY
EAST WINDS UP TO 35 KT LIKELY. IMPROVING TREND THIS EVENING AND
ESPECIALLY AFTER MIDNIGHT WITH MVFR LIKELY ALONG WITH PRECIP
ENDING AROUND 03Z.
OUTLOOK...FRIDAY NIGHT THROUGH TUESDAY...
FRIDAY NIGHT AND SATURDAY...MODERATE CONFIDENCE. CONDITIONS
DETERIORATING TO IFR DURING FRI EVENING AS AREA OF PRECIP MOVES IN.
PTYPE SNOW AND MIXED PRECIP IN THE INTERIOR CHANGING TO RAIN...WITH
MAINLY RAIN NEAR THE COAST. SHOWERS AND IFR PERSISTING INTO
SATURDAY...POSSIBLY IMPROVING TO VFR LATE IN THE DAY. GUSTY S WINDS
CAPE/ISLANDS LATE FRI NIGHT AND SAT MORNING....BECOMING SW DURING
THE AFTERNOON.
SATURDAY NIGHT THROUGH MONDAY...MODERATE CONFIDENCE. MAINLY
VFR...BUT A PERIOD OR TWO OF BRIEF MVFR CONDITIONS ARE POSSIBLE
ESPECIALLY NW ZONES.
TUESDAY...HIGH CONFIDENCE. VFR...BUT OCEAN EFFECT CLOUDS AND A FEW
SNOW SHOWERS MAY BRING MVFR CONDITIONS TO THE OUTER CAPE.
&&
.MARINE...
TONIGHT...
CONTINUED NORTH-NORTHEAST GALES ON THE EASTERN WATERS THIS
EVENING BASED ON OBSERVED BUOY WINDS. WINDS SHOULD DIMINISH
OVERNIGHT...BUT SEAS WILL LINGER ABOVE 5 FEET ON ALL OUTER WATERS.
SMALL CRAFT ADVISORIES WILL COVER ALL ZONES NOT IN A GALE WARNING.
TIDAL RESIDUALS ARE RUNNING AROUND 2.25 FEET HIGH. BUT THE
ASTRONOMICAL TIDES ARE NOT HIGH. SO NO COASTAL FLOODING IS
EXPECTED.
FRIDAY...
WINDS BELOW 25 KNOTS BUT SEAS REMAIN ABOVE 5 FEET ON ALL OUTER
WATERS. SMALL CRAFT ADVISORIES WILL BE NEEDED THROUGH THE DAY ON
THE AFFECTED WATERS.
OUTLOOK...FRIDAY NIGHT THROUGH MONDAY...
FRIDAY NIGHT AND SATURDAY...APPROACHING LOW LEVEL JET WILL BRING SCA
SOUTHERLY WIND GUSTS TO OPEN WATERS LATE FRI NIGHT AND SAT
MORNING...BUT PROBABLY REMAINING BELOW GALE AS STRONG LOW LEVEL
INVERSION WILL PREVENT STRONGER WINDS FROM MIXING DOWN. WINDS SHIFT
TO SW/W SAT AFTERNOON WITH GUSTS TO 25 KT.
SATURDAY NIGHT THROUGH TUESDAY...PERIODS OF SCA GUSTS EXPECTED
THROUGH THE PERIOD. MAINLY WEST WINDS SAT NIGHT INTO MON...SHIFTING
TO N/NW BY TUE.
&&
.CLIMATE...
A PUBLIC INFORMATION STATEMENT WAS ISSUED AT 225 PM. THIS
STATEMENT GIVES A REVIEW OF DECEMBER-JANUARY-FEBRUARY CONDITIONS AT
OUR FOUR CLIMATE SITES...BOSTON-PROVIDENCE-HARTFORD-WORCESTER.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR
CTZ002>004.
MA...WINTER STORM WARNING UNTIL 6 PM EST THIS EVENING FOR
MAZ002>010-012-014-026.
WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR MAZ011-
013-015-016.
NH...WINTER STORM WARNING UNTIL 6 PM EST THIS EVENING FOR NHZ011-
012-015.
RI...WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR RIZ001-
003.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 AM EST FRIDAY FOR ANZ232-235-237.
SMALL CRAFT ADVISORY UNTIL 4 AM EST FRIDAY FOR ANZ233-234.
SMALL CRAFT ADVISORY UNTIL 2 AM EST FRIDAY FOR ANZ230-236.
GALE WARNING UNTIL 2 AM EST FRIDAY FOR ANZ231-250-251-254.
SMALL CRAFT ADVISORY UNTIL 6 AM EST SATURDAY FOR ANZ255-256.
&&
$$
SYNOPSIS...WTB/KJC
NEAR TERM...WTB
SHORT TERM...WTB
LONG TERM...KJC
AVIATION...WTB/KJC
MARINE...WTB/KJC
CLIMATE...
AREA FORECAST DISCUSSION
NWS TAUNTON MA
411 PM EST THU MAR 1 2012
.SYNOPSIS...
LOW PRESSURE RACING ACROSS NEW ENGLAND WILL MOVE OFF TO THE EAST
TONIGHT. HIGH PRESSURE WILL BRING DRY WEATHER OVERNIGHT AND
FRIDAY. STRONG LOW PRESSURE WILL MOVE THROUGH THE GREAT LAKES LATE
FRIDAY INTO FRIDAY NIGHT AND SWING A COLD FRONT THROUGH NEW
ENGLAND SATURDAY. MAINLY DRY AND COLDER WEATHER WILL FOLLOW EARLY
NEXT WEEK...THEN A SIGNIFICANT WARMING TREND IS POSSIBLE TOWARD
MIDDLE AND END OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
LIGHT SNOW ALONG AND NORTH OF THE MASS PIKE WITH VSBYS BELOW 1
MILE IN THE MERRIMACK VALLEY AND PARTS OF THE BOSTON METROWEST.
FARTHER SOUTH LIGHT MIXED RAIN/SNOW ACROSS CT-RI-SOUTHEAST MASS.
RADAR SHOWS THIS PCPN AREA EXTENDS WEST TO CENTRAL NY...SO IT
SHOULD TAKE SEVERAL HOURS FOR THE PCPN TO DIMINISH.
NORTHEAST WINDS LINGERED THROUGH EVENING IN EASTERN MASSACHUSETTS
BUT THE TREND SHOULD BE TOWARD A NORTH WIND ALL AREAS TONIGHT.
THIS WILL DRAW COLDER AIR IN AND SHOULD CONTRIBUTE TO CHANGING
PCPN OVER TO SNOW BEFORE IT ENDS.
UPPER SHORTWAVE OVER NY IS SUPPORTING THIS PCPN. THE SHORTWAVE
WILL CROSS NEW ENGLAND A FEW HOURS EITHER SIDE OF 00Z. ONCE IT
MOVES PAST...PCPN SHOULD TAPER OFF. WE HAVE MAINTAINED LIKELY TO
CATEGORICAL POPS ACROSS SRN NH/MUCH OF MASS/NORTHERN CT/NORTHERN
RI THIS EVENING WITH POPS THEN DIMINISHING OVERNIGHT.
TEMPS/DEWPOINTS ARE A BLEND OF HRRR AND MOS.
WITH ONGOING PCPN AND A FEW HEAVIER SPOTS ON RADAR...WE ARE
MAINTAINING EXISTING WINTER WEATHER HEADLINES THROUGH THE EVENING
RUSH HOUR. BUT WE EXPECT THEY WILL EITHER EXPIRE OR BE EXTENDED
FOR JUST A COUPLE OF ADDITIONAL HOURS.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
HIGH PRESSURE OVER THE MIDWEST MOVES OVER NEW ENGLAND FRIDAY
MORNING. WE EXPECT PARTIAL CLEARING...BUT LINGERING MOISTURE BELOW
850 MB SUGGESTS PARTLY TO MOSTLY CLOUDY SKIES DURING THE DAY.
MEANWHILE...INCREASING MOISTURE AT HIGH LEVELS IN THE WARM
ADVECTION AHEAD OF THE NEXT SYSTEM. SO EXPECT INCREASING HIGH
CLOUDS OVER THE TOP OF ANY LOW CLOUDS.
925 MB TEMPS OF -2C TO -4C SUPPORT MAX TEMPS IN THE MID 30S TO
AROUND 40. A BLEND OF MOS ACHIEVED THIS RANGE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
HIGHLIGHTS...
* MIXED PRECIP AND ICE INTERIOR FRI NIGHT CHANGING TO RAIN...THEN
SHOWERS AND MILD SAT
* MUCH COLDER WITH BELOW NORMAL TEMPS EARLY NEXT WEEK
* WARMING TREND WED INTO THU
FRI NIGHT...
MODELS IN AGREEMENT THAT STRONG LOW PRES WILL BE MOVING NE THROUGH
THE GT LAKES WITH WARM FRONT APPROACHING FROM THE S. WAA PRECIP
WILL BE OVERSPREADING SNE FRI EVENING AND CONTINUING THROUGH THE
NIGHT. SOUNDINGS AND PARTIAL THICKNESSES INDICATE ENOUGH COLD AIR
IN THE COLUMN TO SUPPORT A PERIOD OF SNOW THEN ICE IN THE DISTANT
INTERIOR BEFORE MILDER AIR GRADUALLY PUSHES NORTHWARD. DO NOT
EXPECT MUCH SNOW ACCUM AS MID LEVELS ARE WARMING QUICKLY...BUT AN
EXTENDED PERIOD OF FREEZING RAIN AND ICING IS POSSIBLE MAINLY N OF
I90 AND W OF I495 WHERE LOW LEVEL COLD AIR WILL BE SLOW TO SCOUR
OUT...AND WINTER WX ADVISORIES WILL LIKELY BE NEEDED. DO NOT EXPECT
SIGNIFICANT ICE ACCUM BUT UP TO A TENTH OF AN INCH OF ICE ACCRETION
IS POSSIBLE. EVEN ALONG THE COAST...THE RAIN MAY MIX WITH SLEET AT
THE ONSET. SLOWLY RISING TEMPS OVERNIGHT.
SATURDAY...
SHOWERS WILL CONTINUE INTO SAT AS WARM FRONT LIFTS NWD INTO
REGION...BUT FOCUS WILL GRADUALLY SHIFT TO THE COAST ASSOCD WITH
MODEST LOW LEVEL JET...THEN SHOWERS MOVE OFFSHORE DURING THE
AFTERNOON AS FRONT MOVES THROUGH. POPS WILL BE DECREASING FROM WEST
TO EAST DURING THE DAY. THERE IS STILL AN ELEVATED THUNDER
THREAT...MAINLY NEAR THE S COAST IN THE MORNING AS AREA OF SUBZERO
SWI AND MID 50S TT MOVE NWD. SFC INSTABILITY IS NIL AND LLJ IS NOT
AS ROBUST AND IS FURTHER OFFSHORE SO WIND THREAT IS MINIMAL. AS
WARM FRONT LIFTS NWD ACROSS THE COASTAL PLAIN...TEMPS WILL LIKELY
SPIKE WELL INTO THE 50S...ESPECIALLY RI AND SE MA...BUT TEMPS
PROBABLY HOLDING IN THE 40S N OF THE PIKE.
SUNDAY THROUGH TUESDAY...
MID LEVEL TROF WILL BE MOVING EAST INTO NEW ENG BRINGING A
NOTICEABLE COOLING TREND. STILL MILD SUNDAY...THEN COLDER WITH
BELOW NORMAL TEMPS MON AND TUE. IN FACT...MINS WILL LIKELY DROP
DOWN INTO THE SINGLE MUMBERS AND TEENS MON NIGHT. COASTAL STORMS
EXPECTED TO REMAIN OFFSHORE SUN AND MON...BUT SERIES OF SHORTWAVES
AND SFC TROFS MOVING INTO THE REGION MAY BRING A FEW RAIN/SNOW SUN
AND MON. MOSTLY SUNNY AND DRY WEATHER EXPECTED TUE AS SFC HIGH
BUILDS IN FROM THE WEST...BUT OCEAN EFFECT SNOW SHOWERS MAY AFFECT
THE OUTER CAPE.
WEDNESDAY AND THURSDAY...
GFS AND ECMWF INDICATE A SIGNIFICANT WARMING TREND AS HIGH PRES
MOVES S OF THE COAST WITH RETURN FLOW DEVELOPING. WED WILL BE THE
TRANSITION DAY AFTER A COLD START...THEN UNSEASONABLY MILD WEATHER
POSSIBLE BY THU AND ECMWF HAS THE POTENTIAL FOR TEMPS TO REACH THE
LOWER 60S. DID NOT GO QUITE THAT HIGH IN THE FORECAST AS THIS IS
STILL 7 DAYS AWAY.
&&
.AVIATION /21Z THURSDAY THROUGH TUESDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT
MODERATE...30 PERCENT TO 60 PERCENT
HIGH...GREATER THAN 60 PERCENT
THROUGH 00Z...
MIXED IFR AND MVFR CEILINGS/VSBYS IN RAIN AND SNOW. THESE
CONDITIONS SHOULD CONTINUE THROUGH 00Z. HIGH CONFIDENCE.
TONIGHT...
LEFTOVER MVFR/IFR CONDITIONS THROUGH 03Z ESPECIALLY BDL-PVD NORTH.
NORTH WINDS ALL AREAS. CONDITIONS SHOULD IMPROVE TO MVFR CEILINGS
AND UNRESTRICTED VSBYS OVERNIGHT. MODERATE CONFIDENCE.
FRIDAY...
CONDITIONS IMPROVE TO VFR FRIDAY MORNING. LIGHT WINDS SHIFT TO
SOUTHEAST BY AFTERNOON. HIGH CONFIDENCE.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF. IFR CONDITIONS IN RAIN
THIS MORNING CHANGING TO SNOW THIS AFTERNOON. AN ADDITIONAL INCH OR
TWO OF ACCUMULATION POSSIBLE...MAINLY ON NON PAVED SURFACES. GUSTY
EAST WINDS UP TO 35 KT LIKELY. IMPROVING TREND THIS EVENING AND
ESPECIALLY AFTER MIDNIGHT WITH MVFR LIKELY ALONG WITH PRECIP
ENDING AROUND 03Z.
OUTLOOK...FRIDAY NIGHT THROUGH TUESDAY...
FRIDAY NIGHT AND SATURDAY...MODERATE CONFIDENCE. CONDITIONS
DETERIORATING TO IFR DURING FRI EVENING AS AREA OF PRECIP MOVES IN.
PTYPE SNOW AND MIXED PRECIP IN THE INTERIOR CHANGING TO RAIN...WITH
MAINLY RAIN NEAR THE COAST. SHOWERS AND IFR PERSISTING INTO
SATURDAY...POSSIBLY IMPROVING TO VFR LATE IN THE DAY. GUSTY S WINDS
CAPE/ISLANDS LATE FRI NIGHT AND SAT MORNING....BECOMING SW DURING
THE AFTERNOON.
SATURDAY NIGHT THROUGH MONDAY...MODERATE CONFIDENCE. MAINLY
VFR...BUT A PERIOD OR TWO OF BRIEF MVFR CONDITIONS ARE POSSIBLE
ESPECIALLY NW ZONES.
TUESDAY...HIGH CONFIDENCE. VFR...BUT OCEAN EFFECT CLOUDS AND A FEW
SNOW SHOWERS MAY BRING MVFR CONDITIONS TO THE OUTER CAPE.
&&
.MARINE...
TONIGHT...
CONTINUED NORTH-NORTHEAST GALES ON THE EASTERN WATERS THIS
EVENING BASED ON OBSERVED BUOY WINDS. WINDS SHOULD DIMINISH
OVERNIGHT...BUT SEAS WILL LINGER ABOVE 5 FEET ON ALL OUTER WATERS.
SMALL CRAFT ADVISORIES WILL COVER ALL ZONES NOT IN A GALE WARNING.
TIDAL RESIDUALS ARE RUNNING AROUND 2.25 FEET HIGH. BUT THE
ASTRONOMICAL TIDES ARE NOT HIGH. SO NO COASTAL FLOODING IS
EXPECTED.
FRIDAY...
WINDS BELOW 25 KNOTS BUT SEAS REMAIN ABOVE 5 FEET ON ALL OUTER
WATERS. SMALL CRAFT ADVISORIES WILL BE NEEDED THROUGH THE DAY ON
THE AFFECTED WATERS.
OUTLOOK...FRIDAY NIGHT THROUGH MONDAY...
FRIDAY NIGHT AND SATURDAY...APPROACHING LOW LEVEL JET WILL BRING SCA
SOUTHERLY WIND GUSTS TO OPEN WATERS LATE FRI NIGHT AND SAT
MORNING...BUT PROBABLY REMAINING BELOW GALE AS STRONG LOW LEVEL
INVERSION WILL PREVENT STRONGER WINDS FROM MIXING DOWN. WINDS SHIFT
TO SW/W SAT AFTERNOON WITH GUSTS TO 25 KT.
SATURDAY NIGHT THROUGH TUESDAY...PERIODS OF SCA GUSTS EXPECTED
THROUGH THE PERIOD. MAINLY WEST WINDS SAT NIGHT INTO MON...SHIFTING
TO N/NW BY TUE.
&&
.CLIMATE...
A PUBLIC INFORMATION STATEMENT WAS ISSUED AT 225 PM. THIS
STATEMENT GIVES A REVIEW OF DECEMBER-JANUARY-FEBRUARY CONDITIONS AT
OUR FOUR CLIMATE SITES...BOSTON-PROVIDENCE-HARTFORD-WORCESTER.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR
CTZ002>004.
MA...WINTER STORM WARNING UNTIL 6 PM EST THIS EVENING FOR
MAZ002>010-012-014-026.
WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR MAZ011-
013-015-016.
NH...WINTER STORM WARNING UNTIL 6 PM EST THIS EVENING FOR NHZ011-
012-015.
RI...WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR RIZ001-
003.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 AM EST FRIDAY FOR ANZ232-235-237.
SMALL CRAFT ADVISORY UNTIL 4 AM EST FRIDAY FOR ANZ233-234.
SMALL CRAFT ADVISORY UNTIL 2 AM EST FRIDAY FOR ANZ230-236.
GALE WARNING UNTIL 2 AM EST FRIDAY FOR ANZ231-250-251-254.
SMALL CRAFT ADVISORY UNTIL 6 AM EST SATURDAY FOR ANZ255-256.
&&
$$
SYNOPSIS...WTB/KJC
NEAR TERM...WTB
SHORT TERM...WTB
LONG TERM...KJC
AVIATION...WTB/KJC
MARINE...WTB/KJC
CLIMATE...
AREA FORECAST DISCUSSION
NWS TAUNTON MA
341 PM EST THU MAR 1 2012
.SYNOPSIS...
LOW PRESSURE RACING ACROSS NEW ENGLAND WILL MOVE OFF TO THE EAST
TONIGHT. HIGH PRESSURE WILL BRING DRY WEATHER OVERNIGHT AND
FRIDAY. ANOTHER LOW PRESSURE AREA WILL MOVE THROUGH THE GREAT
LAKES FRIDAY AND SWING A COLD FRONT THROUGH NEW ENGLAND SATURDAY.
HIGH PRESSURE WILL BRING DRY COOL WEATHER FOR THE FIRST HALF OF
NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
LIGHT SNOW ALONG AND NORTH OF THE MASS PIKE WITH VSBYS BELOW 1
MILE IN THE MERRIMACK VALLEY AND PARTS OF THE BOSTON METROWEST.
FARTHER SOUTH LIGHT MIXED RAIN/SNOW ACROSS CT-RI-SOUTHEAST MASS.
RADAR SHOWS THIS PCPN AREA EXTENDS WEST TO CENTRAL NY...SO IT
SHOULD TAKE SEVERAL HOURS FOR THE PCPN TO DIMINISH.
NORTHEAST WINDS LINGERED THROUGH EVENING IN EASTERN MASSACHUSETTS
BUT THE TREND SHOULD BE TOWARD A NORTH WIND ALL AREAS TONIGHT.
THIS WILL DRAW COLDER AIR IN AND SHOULD CONTRIBUTE TO CHANGING
PCPN OVER TO SNOW BEFORE IT ENDS.
UPPER SHORTWAVE OVER NY IS SUPPORTING THIS PCPN. THE SHORTWAVE
WILL CROSS NEW ENGLAND A FEW HOURS EITHER SIDE OF 00Z. ONCE IT
MOVES PAST...PCPN SHOULD TAPER OFF. WE HAVE MAINTAINED LIKELY TO
CATEGORICAL POPS ACROSS SRN NH/MUCH OF MASS/NORTHERN CT/NORTHERN
RI THIS EVENING WITH POPS THEN DIMINISHING OVERNIGHT.
TEMPS/DEWPOINTS ARE A BLEND OF HRRR AND MOS.
WITH ONGOING PCPN AND A FEW HEAVIER SPOTS ON RADAR...WE ARE
MAINTAINING EXISTING WINTER WEATHER HEADLINES THROUGH THE EVENING
RUSH HOUR. BUT WE EXPECT THEY WILL EITHER EXPIRE OR BE EXTENDED
FOR JUST A COUPLE OF ADDITIONAL HOURS.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
HIGH PRESSURE OVER THE MIDWEST MOVES OVER NEW ENGLAND FRIDAY
MORNING. WE EXPECT PARTIAL CLEARING...BUT LINGERING MOISTURE BELOW
850 MB SUGGESTS PARTLY TO MOSTLY CLOUDY SKIES DURING THE DAY.
MEANWHILE...INCREASING MOISTURE AT HIGH LEVELS IN THE WARM
ADVECTION AHEAD OF THE NEXT SYSTEM. SO EXPECT INCREASING HIGH
CLOUDS OVER THE TOP OF ANY LOW CLOUDS.
925 MB TEMPS OF -2C TO -4C SUPPORT MAX TEMPS IN THE MID 30S TO
AROUND 40. A BLEND OF MOS ACHIEVED THIS RANGE.
&&
.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
HIGHLIGHTS...
* A STOUT LOW PRESSURE SYSTEM WILL BRING A GOOD SOAKING ACROSS SNE
ON SATURDAY WHILE SOUTHERN NH MAY SEE SOME MIXED PRECIP EARLY
SAT MORNING.
* HIGH PRESSURE WILL DOMINATE THE UPCOMING WORK WEEK
FRIDAY NIGHT-SATURDAY...MODERATE TO HIGH CONFIDENCE.
MAIN FOCUS OF THE FORECAST WAS FOR THE SYSTEM MOVING THROUGH LATE
FRIDAY INTO SATURDAY. UPPER LEVEL WAVE OVER THE NORTHWEST WILL MOVE
ACROSS THE CONUS AND ADVANCE TOWARDS NEW ENGLAND BY FRIDAY EVENING.
THIS WAVE WILL SPAWN A STOUT LOW PRESSURE SYSTEM MOVING THROUGH THE
PLAIN AND GREAT LAKES REGION. THIS LOW PRESSURE SYSTEM WILL PUSH A
COLD FRONT ACROSS THE AREA EARLY SATURDAY MORNING.
EXPECT PRECIP TO BEGIN EARLY SATURDAY MORNING AND WHILE TEMPS WILL
WARM SIGNIFICANTLY...THIS WONT OCCUR UNTIL LATER IN THE DAY. TEMPS
ESP ACROSS NORTHERN MASS AND NH WILL BE AT OR JUST BELOW
FREEZING...AND WITH THICKNESS PROFILES SHOWING A WARM NOSE MOVING
THROUGH...COULD SEE SOME MIXED PRECIP EARLY SATURDAY MORNING. RIGHT
NOW ONLY FORECASTING LESS THAN 0.1 INCH OF ICE ACROSS SOUTHERN NEW
HAMPSHIRE WHILE SNOWFALL IS LESS THAN AN INCH NORTH OF THE MASS
PIKE. STILL SOME UNCERTAINTY WITH THIS SYSTEM SO STAY TUNED TO
LATER FORECASTS.
STRONG WAA AHEAD OF THIS SYSTEM WILL INCREASE TEMPS WELL INTO THE
50S ACROSS SOUTHERN NEW ENGLAND. A 70KT 850MB JET WILL STREAK
THROUGH THE AREA. HOWEVER LAPSE RATES ARE NOT THE STRONG SO DO NOT
EXPECT GREAT MIXING. BELIEVE WINDS WILL BE 20-30KTS WITH HIGHER
AMOUNTS ACROSS THE CAPE AND ISLANDS.
THE LAST PIECE TO THIS COMPLEX SYSTEM IS THE THUNDER POTENTIAL. THE
BEST AREA TO SEE THUNDER WILL BE ACROSS THE SOUTHERN TIER OF THE
FORECAST AREA AS STOUT COLD FRONT WILL BULGE THROUGH THIS REGION.
MOISTURE LEVELS WILL INCREASE SIGNIFICANTLY AS WELL IN THIS REGION
AND INSTABILITY PARAMETERS ARE ALSO SIGNIFICANT TO THIS TIME OF
YEAR. THE NAM IS MORE ROBUST IN THE THUNDER POTENTIAL THAN THE
GFS...BUT CANNOT IGNORE THE INGREDIENTS THAT ARE COMING
TOGETHER...GOOD LIFT...INSTABILITY AND MOISTURE. DO NOT EXPECT THESE
STORM TO BE STRONG OR SEVERE...BUT SOME SMALL HAIL MAY FALL AS FREEZING
HEIGHT LEVELS ARE LOW. ALSO WOULD WATCH THE POTENTIAL FOR DOWNBURSTS
AS STRONG LOW LEVEL JET IS OVER THE REGION...IF STORMS DECIDE TO TAP
INTO IT THEN A GOOD CHANCE FOR SOME STRONG DOWNBURST TO OCCUR.
THUNDER POTENTIAL WILL DECREASE BY SUNDOWN AS SURFACE HEATING WILL
BE MINIMAL TO HELP FUEL THE STORMS.
SATURDAY NIGHT-MONDAY...MODERATE CONFIDENCE.
BROAD UPPER LEVEL TROUGH WILL CONTINUE TO MOVE ACROSS THE AREA
DURING THIS TIME FRAME. THIS TROUGH WILL KEEP CLOUDS LINGERING
THROUGH THE REST OF THE WEEKEND. CANNOT RULE OUT PRECIPITATION AS
LOW LEVELS ARE STILL SOMEWHAT MOIST. IF ANYTHING IT WOULD BE IN THE
FORM OF DRIZZLE...BUT LOW CONFIDENCE ON THAT OCCURRING. CAA WILL MOVE
THROUGH THE REGION ON MONDAY DECREASING MAX T TO MORE SEASONABLE
TEMPERATURES COMPARED TO THIS WEEKENDS UPPER 45 TO MID 50S. A GOOD
JET MAX WILL SWING THROUGH THE TROUGH ON SUNDAY MORNING...ALLOWING
FOR GUSTY WINDS REGION WIDE ON SUNDAY AS WELL AS ON MONDAY.
TUESDAY-THURSDAY...MODERATE CONFIDENCE.
MODEL DISAGREEMENT DURING THIS TIME FRAME AS LOWERED CONFIDENCE
LEVEL. HAVE TRENDED TOWARDS THE ECMWF AS THE LATEST GFS IS MORE
PROGRESSIVE. EVEN THE GFS ENSEMBLES HAS A FEW MEMBERS IN LINE WITH
THE ECMWF. EXPECT HIGH PRESSURE TO MOVE THROUGH MONDAY NIGHT
CLEARING OUR SKIES BY EARLY TUESDAY. HIGH PRESSURE SHOULD REMAIN
THROUGH THE REST OF THIS TIME PERIOD WHILE ANOTHER UPPER LEVEL
TROUGH WILL APPROACH THE REGION THURSDAY NIGHT.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT
MODERATE...30 PERCENT TO 60 PERCENT
HIGH...GREATER THAN 60 PERCENT
THROUGH 00Z...
MIXED IFR AND MVFR CEILINGS/VSBYS IN RAIN AND SNOW. THESE
CONDITIONS SHOULD CONTINUE THROUGH 00Z. HIGH CONFIDENCE.
TONIGHT...
LEFTOVER MVFR/IFR CONDITIONS THROUGH 03Z ESPECIALLY BDL-PVD NORTH.
NORTH WINDS ALL AREAS. CONDITIONS SHOULD IMPROVE TO MVFR CEILINGS
AND UNRESTRICTED VSBYS OVERNIGHT. MODERATE CONFIDENCE.
FRIDAY...
CONDITIONS IMPROVE TO VFR FRIDAY MORNING. LIGHT WINDS SHIFT TO
SOUTHEAST BY AFTERNOON. HIGH CONFIDENCE.
KBOS TERMINAL...HIGH CONFIDENCE IN TAF. IFR CONDITIONS IN RAIN
THIS MORNING CHANGING TO SNOW THIS AFTERNOON. AN ADDITIONAL INCH OR
TWO OF ACCUMULATION POSSIBLE...MAINLY ON NON PAVED SURFACES. GUSTY
EAST WINDS UP TO 35 KT LIKELY. IMPROVING TREND THIS EVENING AND
ESPECIALLY AFTER MIDNIGHT WITH MVFR LIKELY ALONG WITH PRECIP
ENDING AROUND 03Z.
OUTLOOK...FRIDAY NIGHT THROUGH TUESDAY...
SATURDAY...MODERATE CONFIDENCE. PERIODS OF MVFR-IFR CONDITIONS
LIKELY IN RAIN. SOUTH EAST WIND GUSTS WILL LIKELY REACH 25-35 KT ACROSS
E MA/RI...HIGHEST ACROSS S COAST AND THE ISLANDS.
SATURDAY NIGHT THROUGH MONDAY...MODERATE CONFIDENCE. PROBABLY VFR
THE MAJORITY OF THE TIME...BUT A PERIOD OR TWO OF MVFR CONDITIONS
ARE POSSIBLE.
&&
.MARINE...
TONIGHT...
CONTINUED NORTH-NORTHEAST GALES ON THE EASTERN WATERS THIS
EVENING BASED ON OBSERVED BUOY WINDS. WINDS SHOULD DIMINISH
OVERNIGHT...BUT SEAS WILL LINGER ABOVE 5 FEET ON ALL OUTER WATERS.
SMALL CRAFT ADVISORIES WILL COVER ALL ZONES NOT IN A GALE WARNING.
TIDAL RESIDUALS ARE RUNNING AROUND 2.25 FEET HIGH. BUT THE
ASTRONOMICAL TIDES ARE NOT HIGH. SO NO COASTAL FLOODING IS
EXPECTED.
FRIDAY...
WINDS BELOW 25 KNOTS BUT SEAS REMAIN ABOVE 5 FEET ON ALL OUTER
WATERS. SMALL CRAFT ADVISORIES WILL BE NEEDED THROUGH THE DAY ON
THE AFFECTED WATERS.
OUTLOOK...FRIDAY NIGHT THROUGH MONDAY...
FRIDAY NIGHT...SE-S WINDS WILL INCREASE AS NEXT SYSTEM APPROACHES.
SEAS WILL REMAIN SCA CRITERIA OVER THE OUTER WATERS.
SATURDAY...STRONG LOW LEVEL JET WILL MOVE ACROSS THE WATERS AHEAD
OF APPROACHING COLD FRONT. EXPECT S-SW WINDS TO GUSTING UP TO GALE
FORCE OVER THE OPEN WATERS SAT AFTERNOON. SEAS WILL BUILD UP TO
10-12 FT...HIGHEST ON THE SOUTHERN OUTER WATERS.
SATURDAY NIGHT THROUGH MONDAY...MAY SEE LEFTOVER GALE FORCE GUSTS
EARLY SAT NIGHT ON THE EASTERN OUTER WATERS. OTHERWISE...ENOUGH
COLD AIR ADVECTION SHOULD RESULT IN SCA NORTHWEST WIND GUSTS AND
SEAS ACROSS THE OUTER WATERS FOR A GOOD PORTION OF THE PERIOD. .
&&
.CLIMATE...
A PUBLIC INFORMATION STATEMENT WAS ISSUED AT 225 PM. THIS
STATEMENT GIVES A REVIEW OF DECEMBER-JANUARY-FEBRUARY CONDITIONS AT
OUR FOUR CLIMATE SITES...BOSTON-PROVIDENCE-HARTFORD-WORCESTER.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR
CTZ002>004.
MA...WINTER STORM WARNING UNTIL 6 PM EST THIS EVENING FOR
MAZ002>010-012-014-026.
WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR MAZ011-
013-015-016.
NH...WINTER STORM WARNING UNTIL 6 PM EST THIS EVENING FOR NHZ011-
012-015.
RI...WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR RIZ001-
003.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST FRIDAY FOR ANZ230-232>237.
GALE WARNING UNTIL 2 AM EST FRIDAY FOR ANZ231-250-251-254.
SMALL CRAFT ADVISORY UNTIL 6 PM EST FRIDAY FOR ANZ255-256.
&&
$$
SYNOPSIS...WTB/KJC
NEAR TERM...WTB
SHORT TERM...WTB
LONG TERM...KJC
AVIATION...WTB/KJC
MARINE...WTB/KJC
CLIMATE...
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
324 AM EST THU MAR 1 2012
.DISCUSSION...
MARCH BEGINS WITH A CONTINUATION OF A SUMMER TYPE REGIME AND ITS
UNUSUAL THIS EARLY TO CONSIDER SEA BREEZE BOUNDARY COLLISIONS AND
WET SEASON CONVECTIVE PARAMETERS. A LATE BREEZE MERGER ON WEDNESDAY
PRODUCED MEASURABLE RAIN IN A FEW SPOTS OVER THE INTERIOR PENINSULA.
TODAY/TONIGHT...SFC RIDGING ANCHORED OVER THE WRN ATLC WILL LEAD TO
ANOTHER ROUND OF WARM AFTERNOON TEMPERATURES AFTER CLEARING OF SOME
MORNING STRATUS CLOUDS. SWEST FLOW ALOFT HAS BECOME A LITTLE MORE
ROBUST SINCE WEDNESDAY AND THIS WL PROMOTE A BREEZE MERGER OVER THE
EAST PORTION OF THE PENINSULA TO PERHAPS THE I-95 CORRIDOR BY LATE
AFTERNOON. NEITHER RUC OR NAM REGIONAL GUIDANCE IS INDICATING ENOUGH
RAINFALL POTENTIAL TO MENTION POP IN TODAYS FORECAST WITH MOISTURE
LEVELS ON THE LOW SIDE. WL KEEP A SMALL PERCENTAGE CHC IN GRIDS
ONLY ATTM. BEST CHC FOR A LATE SHOWER WILL BE FROM AROUND CAPE
CANAVERAL SOUTH ALONG THE TREASURE COAST AT MID TO LATE AFTN.
HIGHS WILL BE WELL INTO THE 80S INLAND TO THE LOWER 80S AT THE
COAST BEFORE ONSHORE BREEZE MODIFICATION BY MID AFTERNOON.MILD
AGAIN TONIGHT WITH LIGHT SOUTH TO SW WINDS AND PATCHY STRATUS/FOG
LATE AND LOWS QUITE MILD IN THE 60S.
FRI-SAT...LOW LEVEL RIDGE AXIS SOUTH OF FLORIDA ON FRI WHILE WARM
FRONT ASSOCIATED WITH OCCLUDING LOW OVER MISSOURI/ILLINOIS REMAINS
WELL NORTH OF CENTRAL FLORIDA. DEEPENING SOUTH TO SOUTHWEST FLOW
PULLS WARM AIR MASS UP THE PENINSULA BUT WITH MID AND UPPER LEVEL
SUPPORT WELL NORTH AND A BRISK SOUTH TO SOUTHWEST WIND WILL HOLD ANY
SEA BREEZE FORMING TO THE IMMEDIATE COAST. THE SOUTH TO SOUTHWEST
WIND IS USUALLY CONDUCIVE FOR VERY WARM TEMPERATURES ALONG THE
FLORIDA EAST COAST AND PUSHES HIGHS INTO THE MID AND UPPER 80S ON
FRI. CONTINUED SOUTH TO SOUTHWEST WIND ON SAT MAKES IT EVEN WARMER
WITH UPPER 80S/NEAR 90 FROM LAKE OKEECHOBEE TO CENTRAL OSCEOLA
COUNTY AND UPPER 80S EVERYWHERE ELSE. SOME 90 DEGREE READINGS NOT
OUT OF THE QUESTION ALONG THE COAST. PRECIPITABLE WATER VALUES
AROUND AN INCH AND VERY LITTLE MID LEVEL SUPPORT RESULT IN RAIN
CHANCES 10 PERCENT OR LESS BOTH DAY.
SUN-MON...BEST CHANCES AT ANY RAIN STARTING OVERNIGHT SAT AS A COLD
FRONT PUSHES ACROSS THE SOUTHEAST AND APPROACHES FLORIDA. DEEPENING
MOISTURE IN PLACE FROM THE PREVIOUS DAYS SOUTH TO SOUTHWEST WINDS
AND WEAK DISTURBANCES MOVING SW TO NE IN THE 500MB FLOW OVERHEAD
GIVE CHANCE OF SHOWERS STARTING IN THE NORTHERN CWA AND SPREADING
INTO THE SOUTHERN CWA SUN MORNING AND LASTING THROUGH THE DAY.
ISOLATED SHOWERS BREVARD OSCEOLA SOUTH SUN EVENING WITH THE PRECIP
EXPECTED TO END AFTER MIDNIGHT AS THE FRONT CLEARS EAST CENTRAL
FLORIDA. STRONG NORTHWEST TO NORTH WIND BEHIND THE FRONT SHOULD
PRODUCE BREEZY CONDITIONS AT THE COAST. COOL NORTHWEST WIND HOLD SUN
HIGHS IN THE UPPER 60S NORTH OF INTERSTATE 4 AND ALONG THE COAST
CAPE CANAVERAL NORTH AND THE LOW 70S THE REST OF EAST CENTRAL
FLORIDA. A WIND SHIFT TO THE NORTH AND OFF THE COASTAL WATERS WILL
HELP TO PUSH HIGHS BACK INTO THE MIDDLE 70S.
TUE-WED...TROUGHING ALOFT OVER THE SOUTHEAST ON MON FLATTENS TO
BECOME NEARLY ZONAL TUE AND WED. SURFACE HIGH EXTENDING FROM THE
GULF OF MEXICO TO THE GREAT LAKES AND NORTH BUILDS AS IT SHIFTS TO
THE EAST COAST TUE AND EXTENDS FROM THE NORTHWEST GULF/TX ALONG THE
U.S. EAST COAST AND TO THE CANADIAN MARITIMES. STABLE MARINE AIR
MASS LIMITS POP TO 10 PERCENT OR LESS BOTH DAYS. STRONG ONSHORE FLOW
WILL PUSH THE MARINE AIR WELL INLAND AND KEEP HIGHS IN THE MID 70S
BOTH DAYS.
&&
.AVIATION...
SOME SPOTS OF STRATUS MAINLY INLAND WITH CIGS NR FL 010
THROUGH 13Z THEN VFR AREA WIDE WITH NO CIGS EXPECTED THROUGH 19Z.
AFT 19Z SOME OCNL CIGS NR SEA BREEZE BOUNDARY AT COASTAL SITES WITH
SCT-BKN FL 035-040 AND ISOLD SHRA THROUGH AROUND 02/00Z.
&&
.MARINE...SFC RIDGE AXIS OVER S FL INTO THURSDAY WITH FLOW OVER
THE MARINE AREA S-SW. WINDS BECOMING ONSHORE BY MID AFTERNOON WITH
DEVELOPMENT OF A SEA BREEZE MAINLY SOUTH OF CAPE CANAVERAL.
AFTERNOON WIND SPEEDS AT 10-15KT WITH SEAS 2-3 FT NEAR SHORE
WATERS AND 3-4FT OFFSHORE THROUGH TONIGHT.
FRI-SAT...SOUTH TO SOUTHWEST FLOW AROUND 10 TO 15 KNOTS FRI
SHIFTS TO THE SOUTHWEST AND WEST AND FRESHENS TO 20 KNOTS SAT AS A
COLD FRONT MOVING ACROSS THE SOUTHEAST AND NORTHERN GULF INCREASES
THE PRESSURE GRADIENT.
SAT NIGHT-SUN NIGHT...SCATTERED SHOWERS AS FRONT MOVES THROUGH AND
EXITS THE AREA SUN NIGHT. SOUTHWEST WINDS SHIFT TO THE WEST BEHIND
THE FRONT THEN NORTH SUN NIGHT AS HIGH PRESSURE BUILDS OVER THE
COASTAL WATERS. WINDS SURGE WITH NORTH WINDS TO 25 KNOTS AND SEAS TO
8 FEET IN THE GULF STREAM SUN MORN THEN DIMINISHING TO 15 TO 20
KNOTS SUN EVE.
MON...WINDS REMAIN OUT OF THE NORTH AT 10 TO 15 KNOTS AS THE
GRADIENT RELAXES WHEN THE SURFACE RIDGE AXIS MOVES OVER THE AREA.
&&
.FIRE WEATHER...
NO SIGNIFICANT CONCERNS FOR CRITICAL CONDITIONS UNTIL DRY AIR MASS
SETTLING IN OVER THE AREA RESULTS IN LOW RH VALUES NORTHWEST AREAS
SUN SPREADING SOUTH OVER THE INTERIOR MON.
&&
.PRELIMINARY POINT TEMPS/POPS...
DAB 83 63 83 64 / 10 10 10 10
MCO 86 64 86 64 / 10 10 10 10
MLB 84 66 84 68 / 10 10 10 10
VRB 84 65 84 67 / 10 10 10 10
LEE 85 64 85 64 / 10 10 10 10
SFB 86 64 85 64 / 10 10 10 10
ORL 85 65 85 66 / 10 10 10 10
FPR 85 64 84 67 / 10 10 10 10
&&
.MLB WATCHES/WARNINGS/ADVISORIES...
FL...NONE.
AM...NONE.
&&
$$
SHORT TERM...PENDERGRAST
LONG TERM....WIMMER
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
932 PM EST FRI MAR 2 2012
.SYNOPSIS...
A STRONG COLD FRONT WILL MOVE INTO THE SOUTHEAST STATES LATE
TONIGHT...THEN SHIFT ACROSS THE REGION SATURDAY AFTERNOON AND
EVENING. HIGH PRESSURE WILL BRIEFLY BUILD BACK INTO THE REGION ON
SUNDAY...BEFORE ANOTHER COLD FRONT CROSSES THE AREA ON MONDAY. A
WEAK COASTAL TROUGH COULD DEVELOP OFF THE SOUTHEAST COAST DURING THE
MIDDLE PART OF NEXT WEEK.
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
AT MID EVENING...SEVERE CONVECTION ONGOING IN THE FORM OF
DISCREET SUPERCELLS IN THE PRE-FRONTAL ENVIRONMENT FROM THE
CAROLINA MOUNTAINS AND NORTH GEORGIA SW TO MUCH OF THE NORTHERN
HALF OF ALABAMA. THE STRONG COLD FRONT EXTENDS FROM CENTRAL
TENNESSEE SW TO NORTHERN MISSISSIPPI.
00Z ANALYSIS TONIGHT REVEALED A WELL DEFINED MID LEVEL SHORT WAVE
PIVOTING ENE OVER THE NORTHERN PART OF GEORGIA WHILE MARKED UPPER
DIFLUENCE SPREADING EAST FROM THE GULF COAST REGION. CHARLESTON/S
00Z SOUNDING TONIGHT WAS VERY DRY FROM 800 MB TO 500 MB WITH A
STRONG MID LEVEL SUBSIDENCE CAP.
LATEST TRENDS CONTINUE TO MONITOR SEVERE WEATHER TO OUR W
OVERNIGHT AS THE ATMOSPHERE ACROSS SE GEORGIA AND SE SOUTH
CAROLINA GRADUALLY BECOMES MORE CONDUCIVE FOR CONVECTION AFTER
MIDNIGHT. LATEST RUC AND NAM PROGS HOLDS ONTO CONVECTIVE
INHIBITION FOR MUCH OF THE REGION TONIGHT HOWEVER WE DO SEE
MID LEVELS DESTABILIZE IMPRESSIVELY AFTER 09Z. WHILE THE
FORECAST ENVIRONMENT IS NOT NEARLY AS IMPRESSIVE THAN WHAT
WE ARE LOOKING AT OVER NORTH GEORGIA AND THE CAROLINAS...
WILL STILL NEED TO WATCH FOR SOME DISCREET ACTIVITY SNEAKING
IN LATE.
NOT MUCH CHANGE TO THE FORECAST THIS EVENING...VERY WARM
TEMPS 64-69 OVERNIGHT. SEA FOG HAS MOVED AWAY FROM THE UPPER
CHARLESTON COUNTY COAST.
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH MONDAY/...
MODEL SOLUTIONS ARE IN GOOD AGREEMENT THROUGH THE SHORT TERM
PERIODS...WITH ONLY SOME MINOR TIMING DIFFERENCES NOTED AMONGST THE
OPERATIONAL SOLUTIONS WITH RESPECT TO THE LARGE SCALE SYNOPTIC
FEATURES.
SATURDAY AND SATURDAY NIGHT...A STRONG COLD FRONT WILL APPROACH
FROM THE WEST SATURDAY MORNING AND PUSH SLOWLY EASTWARD THROUGH
THE FORECAST AREA SATURDAY AFTERNOON AND SATURDAY EVENING. MODEL
SOLUTIONS ARE IN RELATIVELY GOOD AGREEMENT SHOWING THE DEEPEST
MOISTURE REMAINING TO THE WEST OF THE FORECAST AREA THROUGH MUCH
OF THE MORNING...THEN STEADILY INCREASING ACROSS THE AREA SATURDAY
AFTERNOON. QUITE A BIT OF CLOUD COVER IN ADVANCE OF THE COLD FRONT
IS EXPECTED TO LIMIT DESTABILIZATION...BUT THE NAM12 CONTINUES TO
SHOW AROUND 500-600 J/KG OF SURFACE BASED CAPE ALONG WITH LIFTED
INDICES BETWEEN -2 AND -4 DEVELOPING IN ADVANCE OF THE COLD FRONT.
THERE WILL BE PLENTY OF DEEP LAYER SHEAR IN PLACE WITH 0-6 KM BULK
SHEAR VALUES BETWEEN 55 AND 60 KNOTS TO SUPPORT ORGANIZED
CONVECTION...BUT THE LACK OF INSTABILITY ALONG WITH THE BEST
FORCING FOR ASCENT AND DEEPEST MOISTURE LAGGING WELL BEHIND THE
SURFACE COLD FRONT...SHOULD ACT TO REDUCE THE POTENTIAL FOR SEVERE
WEATHER. THAT SAID...GIVEN THE FAVORABLE WIND FIELDS
ALOFT...SEVERE WEATHER CAN/T BE RULED OUT AND WE WILL CONTINUE TO
MENTION THE POSSIBILITY IN THE HAZARDOUS WEATHER OUTLOOK.
WILL KEEP THE HIGHEST POPS CONFINED TO FAR INTERIOR ZONES SATURDAY
MORNING...WITH MANY AREAS ALONG THE COAST LIKELY SEEING DRY
CONDITIONS THROUGH THE MORNING HOURS. INCREASING MOISTURE AND LARGE
SCALE FORCING FOR ASCENT WILL STEADILY INCREASE SHOWER/THUNDERSTORM
CHANCES THROUGH THE AFTERNOON HOURS...AND WILL CARRY CATEGORICAL
POPS MOST LOCALES.
A WAVE OF LOW PRESSURE WILL DEVELOP OFF THE SOUTHEAST COAST SATURDAY
EVENING...AND THIS WILL KEEP A BAND OF DEEP MOISTURE OVER THE
FORECAST AREA THROUGH THE NIGHT. AT THE SAME TIME...STRONG LARGE
SCALE FORCING FOR ASCENT WILL OVERSPREAD THE REGION WITH THE
APPROACH OF A DEEP UPPER LEVEL TROUGH ALONG WITH SUPPORT FROM THE
RIGHT REAR QUAD OF A 160+ KNOT H25 JET. THE MODEL SOLUTIONS EVEN
INDICATE FRONTOGENESIS AND ELEVATED INSTABILITY DEVELOPING OVER THE
FORECAST AREA...SO WIDESPREAD RAIN AND EMBEDDED THUNDERSTORMS CAN BE
EXPECTED THROUGH MUCH OF THE NIGHT. QUITE A GOOD SOAKING RAINFALL IS
EXPECTED...WITH MANY AREAS SEEING 2 TO 3 INCHES OF RAIN WITH LOCALLY
HIGHER AMOUNTS BEFORE THE RAIN ENDS SUNDAY MORNING.
HIGH TEMPERATURES SATURDAY ARE EXPECTED TO RANGE FROM AROUND 70
ACROSS THE FAR INTERIOR...TO THE MIDDLE/UPPER 70S CLOSER TO THE
COAST. LOWS SATURDAY NIGHT WILL BOTTOM OUT IN THE LOW TO MID 40S
MOST LOCALES.
SUNDAY...A STRONG UPPER LEVEL TROUGH WILL SWEEP THROUGH THE
REGION SUNDAY MORNING...KICKING THE AREA OF LOW PRESSURE AND BAND
OF DEEP MOISTURE EASTWARD AND IN THE ATLANTIC. RAIN WILL END
FAIRLY QUICKLY FROM WEST TO EAST DURING THE MORNING HOURS...WITH
RAIN FREE CONDITIONS AND CLEARING SKIES EXPECTED DURING THE
AFTERNOON. HIGH TEMPERATURES ARE EXPECTED TO TOP OUT IN THE UPPER
50S TO LOWER 60S.
SUNDAY NIGHT AND MONDAY...HIGH PRESSURE WILL HOLD IN PLACE OVER
THE REGION SUNDAY NIGHT BEFORE A MOISTURE STARVED COLD FRONT
SWEEPS THROUGH THE AREA MONDAY AFTERNOON. WILL CONTINUE TO KEEP
THE FORECAST RAIN FREE...WITH GENERALLY CLEAR TO PARTLY CLOUDY
SKIES ANTICIPATED. LOWS SUNDAY NIGHT WILL BOTTOM OUT IN THE MID TO
UPPER 30S AWAY FROM THE COAST. HIGHS ON MONDAY WILL TOP OUT IN THE
MID TO UPPER 60S.
LAKE WINDS...STRONG AND GUSTY WINDS WILL DEVELOP SATURDAY MORNING
ACROSS LAKE MOULTRIE IN ADVANCE OF AN APPROACHING COLD FRONT. AS A
RESULT...A LAKE WIND ADVISORY HAS BEEN ISSUED.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
OVERALL THE LONG TERM PERIOD WILL BE DOMINATED BY RIDGING ALOFT AND
HIGH PRESSURE AT THE SURFACE. THE SURFACE HIGH WILL SETTLE INTO THE
AREA STARTING MONDAY NIGHT AND IS EXPECTED TO LINGER ALONG THE
EASTERN SEABOARD THROUGH THE END OF THE WEEK. MODELS CONTINUE TO
DEPICT THE DEVELOPMENT OF A WEAK COASTAL TROF BY MID WEEK...AND I
HAVE KEPT POPS OVER THE COASTAL WATERS IN THE SLIGHT CHANCE RANGE.
TEMPERATURES FEATURE A WARMING/MODERATING TREND STARTING OFF BELOW
NORMAL ON TUESDAY (NEAR 60 TO THE LOW 60S)...REACHING THE LOW TO MID
70S BY FRIDAY.
&&
.AVIATION /02Z SATURDAY THROUGH WEDNESDAY/...
KCHS...LOW CLOUDS AND FOG ASSOCIATED WITH TRANSIENT AREAS OF SEA
FOG HAVE BEEN LURKING JUST OFF TO THE E AND SE OF THE TERMINAL
WITH VISIBILITY SATELLITE IMAGERY SHOWED THE IFR CIGS MOVING N
BEFORE SUNSET. WE HAVE KEPT LOW CLOUDS OUT OF THE TAF UNTIL TRENDS
SUGGEST OTHERWISE. WE MAINTAINED LLWS TONIGHT AND EARLY SAT MORNING.
COMPLEX MIX OF CONVECTION EXPECTED SAT AFTERNOON WITH POTENTIAL
FOR MVFR OR LOWER CONDITIONS...ESPECIALLY TOWARD THE END OF DAY
ON SAT.
KSAV...THE MAIN CONCERNS OVERNIGHT WILL BE LLWS AND SOME POTENTIAL
FOR MVFR OR LOWER CIGS TO STREAM FROM THE FLORIDA PANHANDLE AND
FAR S GEORGIA TOWARD THE TERMINAL LATER TONIGHT. WE MAINTAIN THE
LLWS BUT WILL WAIT FOR SATELLITE TRENDS TO INTRODUCE ANY LOWER
CLOUDS. SIMILAR TO KCHS...CONVECTIVE RAINS EXPECTED SAT AFTERNOON
WITH POTENTIAL FOR CONVECTIVE WIND GUSTS AND MVFR OR LOWER
CONDITIONS.
EXTENDED AVIATION OUTLOOK...IFR CONDITIONS DUE TO CIGS AND/OR VSBYS
ARE EXPECTED IN WIDESPREAD RAINFALL SATURDAY AFTERNOON THROUGH
SUNDAY MORNING. VFR CONDITIONS WILL RETURN BY LATE SUNDAY MORNING
AND CONTINUE THROUGH THE MIDDLE OF NEXT WEEK.
&&
.MARINE...
UPDATED TO LOWER MARINE FOG ADVISORIES EARLIER AND THINKING THAT
ANY ADDITIONAL FOG WILL LIKELY BE SMALL IN AREAL COVERAGE AND
QUITE TRANSIENT...WE CONTINUED SOME PATCHY FOG MENTIONS.
THE PRESSURE GRADIENT WILL STEADILY TIGHTEN TONIGHT IN ADVANCE OF
A COLD FRONT PROGRESSING EASTWARD THROUGH THE MORNING HOURS. A 40
TO 50 KT LOW LEVEL JET WILL ALSO DEVELOP ACROSS THE MID ATLANTIC
AND SOUTHEAST STATES. SOUTH TO SOUTHWEST FLOW WILL INCREASE
ACCORDINGLY...WITH MARGINAL SMALL CRAFT ADVISORY CONDITIONS BEING
REACHED FOR THE NEARSHORE SOUTH CAROLINA WATERS NORTH OF EDISTO
AND THE OFFSHORE GEORGIA WATERS BEYOND 20 NM. HAVE THUS INITIATED
ADVISORIES ON OUR EVENING UPDATE THIS EVENING.
SATURDAY THROUGH WEDNESDAY...A STRONG COLD FRONT WILL APPROACH
FROM THE WEST ON SATURDAY AND MOVE THROUGH THE MARINE AREA
SATURDAY EVENING. HIGH PRESSURE WILL BRIEFLY BUILD BACK INTO THE
REGION SUNDAY AND SUNDAY NIGHT...FOLLOWED BY THE PASSAGE OF
ANOTHER COLD FRONT LATE MONDAY. HIGH PRESSURE WILL THEN BUILD
NORTH OF THE REGION MONDAY NIGHT THROUGH THE MIDDLE OF NEXT WEEK.
INCREASING SOUTH-SOUTHWEST FLOW WILL NECESSITATE SMALL CRAFT
ADVISORIES FOR MOST MARINE ZONES ON SATURDAY. THE ONE EXCEPTION IS
OVER THE NEARSHORE GEORGIA WATER WHERE WINDS SHOULD REMAIN JUST
BELOW ADVISORY LEVELS. FOLLOWING THE COLD FRONT PASSAGE A BRIEF LULL
IN THE WINDS SHOULD ALLOW WINDS/SEAS TO DROP BELOW ADVISORY LEVELS
ACROSS ALL WATERS LATE SATURDAY AFTERNOON AND SATURDAY EVENING. LOW
PRESSURE WILL THEN DEVELOP OFFSHORE...WITH ANOTHER ROUND OF SMALL
CRAFT ADVISORIES LIKELY AFTER MIDNIGHT SUNDAY AND CONTINUING THROUGH
AT LEAST SUNDAY MORNING. IN FACT...THERE IS AN OUTSIDE SHOT AT GALES
FOR A FEW HOURS IF THE AREA OF LOW PRESSURE STRENGTHENS MORE THAN
CURRENTLY ANTICIPATED. CONDITIONS SHOULD LOWER BELOW ADVISORY LEVELS
ACROSS MOST WATERS BY NOON SUNDAY...BUT MAY LINGER INTO SUNDAY
EVENING ACROSS THE OUTER GEORGIA WATERS. ALL MARINE ZONES SHOULD
THEN SEE A PERIOD WITH WINDS/SEAS BELOW HEADLINE THRESHOLDS MONDAY
AND MONDAY NIGHT. THE DEVELOPMENT OF A COASTAL TROUGH MAY THEN LEAD
TO PORTIONS OF THE WATERS SEEING CONDITIONS REACH SMALL CRAFT LEVELS
ONCE AGAIN TUESDAY THROUGH WEDNESDAY.
&&
.CHS WATCHES/WARNINGS/ADVISORIES...
GA...NONE.
SC...LAKE WIND ADVISORY FROM 10 AM TO 5 PM EST SATURDAY FOR SCZ045.
MARINE...SMALL CRAFT ADVISORY FROM 10 AM TO 5 PM EST SATURDAY FOR
AMZ330-352.
SMALL CRAFT ADVISORY UNTIL 5 PM EST SATURDAY FOR AMZ350-374.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
330 AM CST THU MAR 1 2012
.DISCUSSION...
ISSUED 330 AM CST THU MAR 1 2012
SHORT TERM...TODAY THROUGH SUNDAY NIGHT
999 MB LOW PRESSUR OVER SE SHORES OF LAKE HURON THAT BROUGHT HEAVY
SNOW TO PARTS OF THE UPPER MIDWEST INCLUDING NORTHERN WI WITH 1-2
FEET WILL WEAKEN AS IT TRACKS EAST INTO THE EASTERN GREAT LAKES BY
NOON AND INTO NEW ENGLAND THIS AFTERNOON. MEANWHILE WEAK HIGH
PRESSURE RIDGE FROM AR/MO INTO THE EASTERN DAKOTAS AND WESTERN MN
WILL MOVE OVER THE MID MS VALLEY AND IL BY NOON AND REACH NEAR THE
FOOTHILLS OF THE APPALACHIANS BY SUNSET. STILL GETTING SOME GUSTY
WEST WINDS EARLY THIS MORNING OF 20 TO 30 MPH AND EXPECT THESE
WINDS TO GRADUALLY DIMINISH AS HIGH PRESSURE RIDGE MOVES IN BY
MIDDAY. LOW CLOUDS FROM LINCOLN NE WILL ALSO DECREASE THIS MORNING
AS LOW PRESSURE PULLS AWAY FROM IL. HIGHS RANGING FROM AROUND 50F
NORTH OF I-74 AND UPPER 50S SE IL AND FROM JACKSONVILLE SW. WENT
WARMER THAN GUIDANCE WITH A FAIR AMOUNT OF SUNSHINE TODAY AND 850
MB TEMPS WARMING TO 5-8C BY SUNSET.
DEEPENING UPPER LEVEL TROF INTO THE ROCKIES TO DEVELOP/DEEPEN
SURFACE LOW PRESSURE OVER THE TX/OK PANHANDLE BY SUNSET TODAY AND
THEN EJECT NE INTO CENTRAL IL BY NOON FRI AS IT DEEPENS TO 994 MB
THEN INTO NORTHERN INDIANA BY SUNSET WHILE SWINGING A COLD FRONT
EAST THROUGH CENTRAL/SE IL. MODELS HAVE TRENDED A BIT QUICKER WITH
QPF OVERNIGHT INTO PARTS OF CENTRAL IL ESPECIALLY ECMWF AND NAM
MODEL IN WARM AIR ADVECTION PATTERN. ADDED SLIGHT CHANCE OF
SHOWERS AND THUNDERSTORMS LATE TONIGHT INTO AREAS FROM EFFINGHAM
SOUTH WHERE SPC HAS A SLIGHT RISK OF SEVERE STORMS. BEST CHANCE OF
SHOWERS AND THUNDERSTORMS STILL EXPECTED FRI AND SPC HAS EXPANDED
SLIGHT RISK FROM THE IL RIVER SE WHILE MODERATE RISK SE OF IL OVER
PARTS OF KY/TN AND SE INDIANA. BEST SEVERE WX THREAT WILL BE OVER
SE IL LATE FRI MORNING INTO FRI AFTERNOON WHERE 30% OR HIGHER
RISK. HIGHS FRI RANGE FROM THE LOWER 50S NW OF THE IL RIVER TO THE
UPPER 60S TO NEAR 70F IN SE IL...SE OF I-70.
HAVE CHANCE OF SHOWERS OVER EASTERN IL FRI EVENING THEN MOST OF
AREA DRY OVERNIGHT FRI NIGHT AS STRONG LOW PRESSURE DEEPENS INTO
SE CANADA. MUCH COLDER AIR USHERS INTO IL THIS WEEKEND WITH STRONG
UPPER LEVEL TROF DIGGING INTO THE EASTERN STATES WITH HIGHS IN THE
UPPER 30S TO MID 40S. INCREASED THE CLOUD COVER THIS WEEKEND WITH
DIURNALLY ENHANCED CU/STRATOCU DEVELOPING IN THE AFTERNOON.
CLIPPER SYSTEM TO BRINGING CHANCE OF LIGHT RAIN SHOWERS SUNDAY
WITH LIGHT SNOW SHOWERS POSSIBLE TOO NORTH OF I-72.
LONG TERM...MONDAY THROUGH THURSDAY
STRONG UPPER LEVEL RIDGE SHIFTS EAST INTO THE MS VALLEY AND IL
EARLY NEXT WEEK WITH NICE WARMUP IN STORE WITH 60S TUE/WED.
EXTENDED MODELS DIFFER ON ARRIVAL OF NEXT WEATHER SYSTEM WITH
ECMWF NOW SLOWER AND KEEPING IT DRY OVER IL THROUGH WED EVENING.
GFS IS DRY OVER EASTERN IL WED WITH QPF MOVING INTO WESTERN/NW IL
WED AFTERNOON AHEAD OF APPROACHING COLD FRONT. HAVE CHANCE OF RAIN
SHOWERS WED THRU THU ALONG WITH RISK OF THUNDERSTORMS DURING THIS
TIME.
HUETTL
&&
.AVIATION...
ISSUED 1143 PM CST WED FEB 29 2012
CYCLONIC FLOW AND WRAP AROUND STRATOCUMULUS WILL CONTINUE TO COVER
THE NORTHERN THIRD OF ILLINOIS OVERNIGHT. THE RUC MODEL MOISTURE
FIELDS CONTINUE TO HANDLE THE LOW LEVEL MOISTURE BETTER THAN THE
NAM AND GFS WITH RESPECT TO THESE CLOUDS. THE PROBLEM THOUGH WILL
BE THE SOUTHERN EDGE OF THE CLOUDS GETTING CLOSE TO SEVERAL TAF
SITES IN CENTRAL IL AND WHETHER OR NOT MVFR CIGS WILL FORM.
KPIA IS ALREADY CLOSE TO MVFR CIGS...SO THEY SHOULD DROP BELOW
3 KFT IN THE NEXT HOUR OR SO. BASED ON THE RUC MOISTURE
FIELDS...KBMI SHOULD BE ON THE SOUTHERN EDGE OF THE MVFR CIGS.
THERE IS SOME UNCERTAINTY AS TO THE SKY COVER AT KCMI WHERE A
COMBINATION OF SATELLITE EXTRAPOLATION AND MODEL OUTPUT BARELY
PUTS THE SOUTHERN EDGE OF THE CLOUD SHIELD NEAR THEM. WILL GO WITH
A BKN VFR CIG FOR KCMI AT THIS TIME AND MONITOR THEM THROUGH THE
NIGHT.
THE CLOUDS ARE EXPECTED TO CLEAR IN MOST AREAS BY DAYBREAK WITH A
CONTINUED DECREASE IN THE WIND. HIGH PRESSURE MOVING ACROSS THE
REGION THURSDAY WILL RESULT IN BACKING SURFACE WINDS FROM WEST TO
SOUTH DURING THE AFTERNOON...AND THEN FROM THE EAST-SOUTHEAST BY
EVENING. ALL OF THE MODEL MOISTURE PROFILES AND CU RULE INDICATE A
CLEAR SKY MUCH OF THE DAY AND INTO THE EVENING THURSDAY.
MILLER
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1144 PM CST WED FEB 29 2012
.DISCUSSION...
ISSUED 903 PM CST WED FEB 29 2012
MADE SOME MINOR ADJUSTMENTS TO THE FORECAST/GRIDS FOR TONIGHT. THE
STRONG SURFACE LOW IN NORTHEAST WI IS STILL KEEPING A TIGHT
GRADIENT ACROSS NORTHERN AND CENTRAL IL WITH WIND GUSTS AROUND
35 MPH CONTINUING IN MANY LOCATIONS. AS THE LOW WEAKENS AND DRIFTS
TO THE EAST OVERNIGHT THE WIND WILL CONTINUE ITS GRADUAL DECLINE.
THE OTHER FORECAST CONCERN IS THE WRAP AROUND CLOUD COVER IN PARTS
OF CENTRAL ILLINOIS. THE LATEST SATELLITE LOOP HAS THE SOUTHERN
EDGE OF THIS FROM MACOMB TO JUST NORTH OF DANVILLE. THE 00Z RUC
SEEMS TO HAVE A GREAT HANDLE ON THIS WITH ITS DEPICTION OF THE LOW
LEVEL MOISTURE FIELDS. THUS...WILL KEEP CLOUDS ACROSS NORTH
CENTRAL SECTIONS...WITH PARTLY CLOUDY CONDITIONS IN THE REST OF
CENTRAL IL AND A CLEAR SKY IN THE SOUTHEAST.
NOT PLANNING ANY BIG ADJUSTMENTS TO TEMPERATURES AND LOW LEVEL
COLD ADVECTION SHOULD KEEP READINGS ON A SLOW...STEADY DECLINE
THROUGH THE NIGHT...DESPITE AREAS OF CLOUDS.
&&
.AVIATION...
ISSUED 1143 PM CST WED FEB 29 2012
CYCLONIC FLOW AND WRAP AROUND STRATOCUMULUS WILL CONTINUE TO COVER
THE NORTHERN THIRD OF ILLINOIS OVERNIGHT. THE RUC MODEL MOISTURE
FIELDS CONTINUE TO HANDLE THE LOW LEVEL MOISTURE BETTER THAN THE
NAM AND GFS WITH RESPECT TO THESE CLOUDS. THE PROBLEM THOUGH WILL
BE THE SOUTHERN EDGE OF THE CLOUDS GETTING CLOSE TO SEVERAL TAF
SITES IN CENTRAL IL AND WHETHER OR NOT MVFR CIGS WILL FORM.
KPIA IS ALREADY CLOSE TO MVFR CIGS...SO THEY SHOULD DROP BELOW
3 KFT IN THE NEXT HOUR OR SO. BASED ON THE RUC MOISTURE
FIELDS...KBMI SHOULD BE ON THE SOUTHERN EDGE OF THE MVFR CIGS.
THERE IS SOME UNCERTAINTY AS TO THE SKY COVER AT KCMI WHERE A
COMBINATION OF SATELLITE EXTRAPOLATION AND MODEL OUTPUT BARELY
PUTS THE SOUTHERN EDGE OF THE CLOUD SHIELD NEAR THEM. WILL GO WITH
A BKN VFR CIG FOR KCMI AT THIS TIME AND MONITOR THEM THROUGH THE
NIGHT.
THE CLOUDS ARE EXPECTED TO CLEAR IN MOST AREAS BY DAYBREAK WITH A
CONTINUED DECREASE IN THE WIND. HIGH PRESSURE MOVING ACROSS THE
REGION THURSDAY WILL RESULT IN BACKING SURFACE WINDS FROM WEST TO
SOUTH DURING THE AFTERNOON...AND THEN FROM THE EAST-SOUTHEAST BY
EVENING. ALL OF THE MODEL MOISTURE PROFILES AND CU RULE INDICATE A
CLEAR SKY MUCH OF THE DAY AND INTO THE EVENING THURSDAY.
MILLER
&&
.PREV DISCUSSION...
ISSUED 319 PM CST WED FEB 29 2012
MAIN CONCERNS THIS PACKAGE INCLUDE PCPN FRIDAY THROUGH FRIDAY
NIGHT...AND THEN AGAIN AND THE END OF THE EXTENDED PERIOD...ON
WEDNESDAY.
MODELS IN FAIRLY GOOD AGREEMENT THROUGH ABOUT 36-42 HOURS BUT THEN
DIFFER AFTER THAT...ESPECIALLY WITH THE APPROACHING WEATHER SYSTEM
FOR FRIDAY. THE NAM-WRF IS SLOWER AND FURTHER WEST THAN WITH THE
PREVIOUS RUN...WHILE THE GFS/SREF/GEM ARE FASTER AND MORE EAST.
THE ECMWF IS MUCH DIFFERENT FROM ALL OTHERS AND HAS THE LOW
TRACKING LITTLE FURTHER SOUTH ACROSS SOUTHERN ILLINOIS WITH A
TIMING IN THE MIDDLE. SO BLENDING OF THE MODELS WILL BE TO TAKE THE
TIMING OF THE ECMWF AND THE TRACK OF THE OTHERS...WHICH IS LITTLE
FURTHER NORTH AND EAST. EXTENDED MODELS ARE SIMILAR THROUGH THE
MIDDLE OF THE WEEK...SO A GFS/ECMWF BLEND IS A GOOD FORECAST.
SHORT TERM...TONIGHT THROUGH SATURDAY
THE CURRENT SYSTEM LOCATED NORTH OF THE STATE WILL CONTINUE TO
MOVE EAST INTO SOUTHEASTERN CANADA WITH A RIDGE OF HIGH PRSS
MOVING IN WITH DRY WEATHER FOR TOMORROW AND TOMORROW NIGHT. THEN A
WEATHER SYSTEM WILL DEVELOP IN THE WESTERN PLAINS AND MOVE ACROSS
ILLINOIS FRIDAY. THIS SYSTEM WILL MOVE ENE INTO THE GRT LKS REGION
AND DRAG A COLD FRONT ACROSS THE STATE FRIDAY AFTERNOON. WITH GULF
WIDE OPEN...WILL BE PLENTY OF MOISTURE AND INSTABILITY FOR SHOWERS
AND THUNDERSTORMS ACROSS THE AREA ON FRIDAY. SPC HAS OUR
SOUTHEASTERN AREAS IN A SLIGHT RISK AND THIS STILL SEEMS
REASONABLE FOR NOW. AS THE SYSTEM PUSHES EAST A CHANCE OF PCPN
WILL CONTINUE IN THE EAST FRIDAY EVENING. COLDER AIR WILL ALSO
SPILL IN BEHIND THE SYSTEM CAUSING THE PCPN TO BECOME MIXED WITH
SNOW BEFORE IT ENDS. AFTER THIS SYSTEM...COOLER AIR WILL ADVECT
INTO THE AREA FOR THE WEEKEND.
LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY
A WEAK CLIPPER SYSTEM WILL DIVE SOUTHEAST THROUGH THE AREA SUNDAY.
WITH MOISTURE SEVERELY LACKING...WILL HAVE ONLY A SLIGHT CHC OF
PCPN DURING THE DAY. TEMPS SHOULD BE WARM ENOUGH THAT ANY PCPN
WILL BE LIQUID. THEN RIDGING MOVES BACK INTO THE REGION AFTER THE
WEEKEND AND BRINGS WARMER WEATHER BACK INTO THE CWA FOR THE EARLY
PART OF THE WEEK. EXTENDED MODELS IN FAIRLY GOOD AGREEMENT WITH
THE NEXT SYSTEM EXPECTED TO IMPACT THE CWA FOR WEDNESDAY.
TEMPS WILL BEGIN COOL FOR THE WEEKEND AND THEN BEGIN TO WARM BACK
TO WELL ABOVE NORMAL FOR TUE AND WED.
&&
.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
210 PM MST THU MAR 1 2012
.SHORT TERM...(THIS EVENING THROUGH FRIDAY)
ISSUED AT 200 PM MST THU MAR 1 2012
A COLD FRONT THAT PASSED OVER THE CWA EARLY THIS MORNING IS NOW
ACROSS SOUTHWEST KANSAS AND SOUTHEAST COLORADO. EARLY AFTERNOON WV
IMAGERY AND RUC H5 ANALYSIS SHOW A BROAD TROUGH ACROSS THE WESTERN
US. A STRENGTHENING SHORTWAVE TROUGHS IS CURRENTLY MOVING INTO
WESTERN COLORADO.
TONIGHT THROUGH FRIDAY...SHORTWAVE TROUGH WILL MOVE OUT OF COLORADO
INTO WESTERN KANSAS. MOISTURE/LIFT WILL INCREASE FROM THE WET TO THE
EAST THIS EVENING AHEAD OF THIS FEATURE...WITH BEST LIFT/MOISTURE IN
THE 03-09Z TIMEFRAME. RAIN WILL QUICKLY TRANSITION TO SNOW IN THE
WEST THIS EVENING...WITH A RAIN/SNOW MIX IN THE EAST MOST OF THE
NIGHT. BY SUNRISE MOST LOCATIONS SHOULD SEE RAIN COMPLETELY
TRANSITION TO SNOW. GUIDANCE HAS TRENDED FURTHER SOUTH AND WEST ON
PLACEMENT OF HIGHEST SNOWFALL AMOUNTS...WHICH MAKES SENSE
CONSIDERING THE LOCATION OF SURFACE BAROCLINIC ZONE. WITH THIS IS
MIND...I INCREASED POPS ACROSS THE SOUTHWEST...AND DECREASED POPS IN
THE NORTHEAST. CONSIDERING THE LIMITED MOISTURE ADVECTION...AND
QUICK NATURE OF THIS SYSTEM...SNOWFALL AMOUNTS SHOULD REMAIN LIGHT.
RIGHT NOW HIGHEST AMOUNTS SHOULD BE LIMITED TO EASTERN COLORADO
WHERE 1-2 INCHES IS EXPECTED.
WITH LARGE SCALE SUBSIDENCE BUILDING BACK OVER THE CWA FRIDAY
MORNING FROM THE NORTH...PRECIPITATION SHOULD TAPER OFF QUICKLY FROM
THE NORTH TO THE SOUTH BY MID FRIDAY MORNING OVER ALL BUT THE
EXTREME SOUTHWEST PARTS OF THE CWA. DRY CONDITIONS ARE THEN EXPECTED
THROUGH FRIDAY AFTERNOON ACROSS ALL OF THE CWA.
.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)
ISSUED AT 200 PM MST THU MAR 1 2012
MAIN WEATHER STORY FOR THE LONG TERM IS A WARMING TREND AS LARGE
UPPER RIDGE ALBEIT SOMEWHAT FLAT DEVELOPS OVER THE AREA. HIGH
TEMPERATURE SATURDAY IN THE 40S WILL WARM INTO THE 50S AND LOW 60S
SUNDAY. EVEN WARMER ON MONDAY WITH MID TO UPPER 60S AND MID 60S TO
LOW 70S TUESDAY.
TIMING DIFFERENCES SHOW UP WEDNESDAY AND THURSDAY AS THE WEST
COAST UPPER TROUGH MOVES TOWARD OR ACROSS THE AREA...IMPACTING THE
TEMPERATURE FORECAST. LOOKS TO REMAIN ABOVE NORMAL BOTH DAYS WITH
HIGHS IN THE 50S.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON)
ISSUED AT 1055 AM MST THU MAR 1 2012
VFR CONDITIONS WILL PREVAIL AT KMCK AND THROUGH THE DAY AT KGLD.
TONIGHT...LIGHT SNOW WILL DEVELOP AT KGLD WITH RESTRICTIONS TO
VISIBILITY LIKELY DOWN TO MVFR RANGE. BY FRIDAY MORNING...SNOW
WILL MOVE OUT OF KGLD WITH VFR CONDITIONS THROUGH THE REST OF THE
PERIOD. GUSTY WINDS CAN BE EXPECTED THROUGH 01Z AT WHICH TIME
PRESSURE GRADIENT WILL RELAX AND WINDS WILL DECREASE.
&&
.FIRE WEATHER...
ISSUED AT 200 PM MST THU MAR 1 2012
CRITICAL FIRE WEATHER CONDITIONS REMAIN POSSIBLE ALONG AND SOUTH
OF INTERSTATE 70 SATURDAY AS NORTHWEST WINDS OF 15 TO 25 MPH WITH
HIGHER GUSTS COMBINE WITH AFTERNOON HUMIDITY AS LOW AS 20 PERCENT.
&&
.GLD WATCHES/WARNINGS/ADVISORIES...
CO...NONE.
KS...NONE.
NE...NONE.
&&
$$
SHORT TERM...DR
LONG TERM....007
AVIATION...BAS
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
637 AM EST THU MAR 1 2012
.SYNOPSIS...
COLDER AIR BEHIND THE FRONT MAY STILL PRODUCE SCATTERED LIGHT SHOWERS
ACROSS THE NORTH INTO THE AFTERNOON. ELSEWHERE, CONDITIONS WILL
BE DRY AND SEASONABLE. HIGH PRESSURE WILL MAINTAIN DRY CONDITIONS
TONIGHT AND FRIDAY MORNING. LOW PRESSURE WILL BRING SHOWERS LATE
FRIDAY INTO SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
PER RECENT SURFACE AND RADAR DATA, ALONG WITH HRRR AND WRF-NMM
MODEL OUTPUT, EXPECT SCATTERED SHOWERS OF RAIN AND POSSIBLY
FLURRIES LINGERING ACROSS THE NORTH THROUGH MIDDAY. FARTHER
SOUTH, NAM MODEL PROFILES INDICATE VARIABLE CLOUDINESS.
GFS AND NAM MOS INDICATING TEMPERATURES ONLY REBOUNDING A COUPLE
DEGREES BY THIS AFTERNOON, MAKING DAYTIME HIGHS NEAR NORMAL.
NAM MODEL PROFILES SHOW WINDS CAN GUST TO 25-30 MPH.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
EASTBOUND HIGH PRESSURE WILL PROVIDE A DRY BREAK TONIGHT, WITH
LOWS NEAR OR SLIGHTLY WARMER THAN NORMAL.
SREF MODEL OUTPUT CONTINUES TO SHOW A WELL DEVELOPED LOW PRESSURE
SYSTEM, MOVING NORTHEAST FROM OKLAHOMA TO MICHIGAN, WILL START
PRODUCING SHOWERS ACROSS THE UPPER OHIO VALLEY FRIDAY AFTERNOON.
NAM AND GFS MOS SHOW HIGHS FRIDAY CAN BE 10 TO 15 DEGREES WARMER
THAN NORMAL.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
SREF MODEL OUTPUT SHOWS ONCE THE LOW PRESSURE REACHES MICHIGAN, IT
WILL PUSH COLD FRONTAL BANDS OF SHOWERS EASTWARD ACROSS THE UPPER
OHIO VALLEY FRIDAY NIGHT AND EARLY SATURDAY.
ECMWF MODEL OUTPUT THEN SHOWS A SECONDARY COLD FRONT WILL PROVIDE
FURTHER COOLING SATURDAY NIGHT AND SUNDAY, WITH A MIX OF RAIN AND
SNOW SHOWERS.
ENSUING HIGH PRESSURE SHOULD PROMOTE DRY CONDITIONS AND MODERATING
TEMPERATURES MONDAY INTO WEDNESDAY.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
NAM MODEL PROFILES SHOW COLD POOL STRATOCUMULUS TO OCCASIONALLY
PRODUCE MVFR CEILINGS TODAY, PARTICULARLY FROM PIT NORTH. ISOLATED
MVFR VISIBILITIES MAY BRIEFLY OCCUR WITH MIXED SHOWERS NORTH.
SURFACE WINDS FROM THE WEST CAN GUST TO 25-30 KTS AT TIMES.
HIGH PRESSURE WILL ENSURE VFR AND LESS WIND TONIGHT.
OUTLOOK...THURSDAY NIGHT THROUGH MONDAY...
VFR INTO FRIDAY AFTERNOON. THEN RESTRICTIONS AND SHOWERS POSSIBLE
LATE FRIDAY NIGHT AND SATURDAY AS A LOW PRESSURE SYSTEM TRACKS
NORTHEAST AND PUSHES A COLD FRONT THROUGH THE AREA. A SECONDARY COLD
FRONT WILL PROMOTE POSSIBLE RESTRICTIONS WITH RAIN AND SNOW SUNDAY
INTO EARLY MONDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION...UPDATED
NWS PITTSBURGH PA
129 AM EST THU MAR 1 2012
.SYNOPSIS...
THE POST FRONTAL COLD POOL MAY STILL PRODUCE SCATTERED SHOWERS OF
RAIN AND LIGHT SNOW ACROSS THE NORTH INTO AFTERNOON. FARTHER SOUTH,
CONDITIONS TODAY WILL BE DRY AND SEASONABLE. EASTBOUND HIGH PRESSURE
WILL MAINTAIN DRY CONDITIONS TONIGHT AND FRIDAY MORNING. LOW
PRESSURE, COMING NORTHEAST FROM OKLAHOMA, WILL PROVIDE SHOWERS LATE
FRIDAY INTO SATURDAY, FOLLOWED BY A COOL DOWN WITH SCATTERED SNOW
SHOWERS SUNDAY.
&&
.NEAR TERM /THROUGH TODAY/...
PER RECENT SURFACE AND RADAR DATA, ALONG WITH WRF-NMM MODEL OUTPUT,
EXPECT CURRENT COLD FRONTAL BAND OF SCATTERED SHOWERS AND ISOLATED
THUNDERSTORMS TO EXIT EAST PAST THE MOUNTAINS BEFORE DAWN. HOWEVER,
THERE MAY BE SCATTERED COLD POOL SHOWERS OF RAIN AND POSSIBLY
FLURRY-LIKE SNOW LINGERING ACROSS THE NORTH INTO MIDDAY THURSDAY.
FARTHER SOUTH, NAM MODEL PROFILES INDICATE VARIABLE CLOUDINESS.
USING BLEND OF HRRR AND GFS LAMP, FORECASTED TEMPERATURES TO FALL
INTO THE 40S SOUTH AND 30S NORTH BEFORE MORNING. GFS AND NAM MOS
THEN SHOW A REBOUND OF ONLY A COUPLE DEGREES BY THURSDAY AFTERNOON,
MAKING DAYTIME HIGHS NEAR NORMAL.
NAM MODEL PROFILES SHOW WINDS CAN GUST TO 25-30 MPH.
&&
.SHORT TERM /TONIGHT THROUGH 6 PM FRIDAY/...
EASTBOUND HIGH PRESSURE WILL PROVIDE A DRY BREAK THURSDAY NIGHT,
WITH LOWS NEAR OR SLIGHTLY WARMER THAN NORMAL.
SREF MODEL OUTPUT CONTINUES TO SHOW A WELL DEVELOPED LOW PRESSURE
SYSTEM, MOVING NORTHEAST FROM OKLAHOMA TO MICHIGAN, WILL START
PRODUCING SHOWERS ACROSS THE UPPER OHIO VALLEY FRIDAY AFTERNOON.
NAM AND GFS MOS SHOW HIGHS FRIDAY CAN BE 10 TO 15 DEGREES WARMER
THAN NORMAL.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
SREF MODEL OUTPUT SHOWS ONCE THE LOW PRESSURE REACHES MICHIGAN, IT
WILL PUSH COLD FRONTAL BANDS OF SHOWERS EASTWARD ACROSS THE UPPER
OHIO VALLEY FRIDAY NIGHT AND EARLY SATURDAY.
ECMWF MODEL OUTPUT THEN SHOWS A SECONDARY COLD FRONT WILL PROVIDE
FURTHER COOLING SATURDAY NIGHT AND SUNDAY, WITH A MIX OF RAIN AND
SNOW SHOWERS.
ENSUING HIGH PRESSURE SHOULD PROMOTE DRY CONDITIONS AND MODERATING
TEMPERATURES MONDAY INTO WEDNESDAY.
&&
.AVIATION /07Z THURSDAY THROUGH MONDAY/...
RECENT RADAR AND SURFACE DATA SHOW THE LAST OF IFR COLD FRONTAL
SHOWERS EXITING KDUJ BY 0630Z. THEN NAM MODEL PROFILES SHOW COLD
POOL STRATOCUMULUS TO OCCASIONALLY PRODUCE MVFR CEILINGS OVERNIGHT
AND DAYTIME THURSDAY. ISOLATED MVFR VISIBILITIES CAN OCCUR WITH
MIXED SHOWERS NORTH.
SURFACE WINDS FROM THE WEST CAN GUST TO 25 KTS AT TIMES.
HIGH PRESSURE WILL ENSURE VFR AND LESS WIND TONIGHT.
OUTLOOK...THURSDAY NIGHT THROUGH MONDAY...
VFR INTO FRIDAY AFTERNOON. THEN RESTRICTIONS AND SHOWERS POSSIBLE
LATE FRIDAY NIGHT AND SATURDAY AS A LOW PRESSURE SYSTEM TRACKS
NORTHEAST AND PUSHES A COLD FRONT THROUGH THE AREA. A SECONDARY COLD
FRONT WILL PROMOTE POSSIBLE RESTRICTIONS WITH RAIN AND SNOW SUNDAY
INTO EARLY MONDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
935 PM EST FRI MAR 2 2012
.UPDATE...
ISSUED AT 651 PM EST FRI MAR 2 2012
THE MAIN AREA OF SHOWERS AND THUNDERSTORMS WAS LIFTING NORTH OF
KALAMAZOO AND BATTLE CREEK. WINDS HAVE SHIFTED AT MUSKEGON AND ARE
NOW OUT OF THE NORTH. THIS WILL HELP TO DRAW DOWN THE COLDER AIR
AND RESULT IN A CHANGE OVER TO SNOW IN MUSKEGON BY 9 PM. WINDS
HAVE NOT INCREASED YET...BUT BY 10 PM WE SHOULD BE SEEING THE
POWERFUL GUSTS DEVELOPING ALONG INTERSTATE 94.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 935 PM EST FRI MAR 2 2012
NO HEADLINE/SIGNIFICANT FCST CHANGES ARE PLANNED THIS EVENING. ONE
TO THREE INCHES OF SNOW HAS ALREADY FALLEN ACROSS OUR NNW FCST AREA
WITH NUMEROUS REPORTS OF HAZARDOUS TRAVEL CONDITIONS UP THERE. THE
986 MB SFC LOW IS NOW CENTERED JUST NNE OF GRR. WINDS WILL RAMP UP
LATE THIS EVENING AND OVERNIGHT AND THE HIGH WIND WARNING REMAINS IN
EFFECT TO COVER THAT THROUGH 12Z SAT.
SFC LOW TO TRACK ACROSS KALAMAZOO TO SAGINAW BAY THIS EVENING
WHILE RAPIDLY DEEPENING. LATEST MSAS SHOWS IT AT PRESENTLY 990MB
IN WRN INDIANA AND THE HRR RUC HAS IT 970MB AT 07Z OVER SAGINAW
BAY. AS THE LOW PASSES BY LATER THIS EVENING LOOK FOR WIND GUSTS
APPROACHING OR EXCEEDING WARNING CRITERIA OF 50 KNOTS. THIS IS
SUPPORTED IN FCST SNDGS AND HRR WIND GUST PROGS... WITH BEST
THREAT OVER THE SRN FCST AREA. NOT AS CERTAIN NORTH OF ST JOHNS.
BEST WINDOW FOR SVR GUSTS IS ROUGHLY 04Z-08Z... BUT WILL HAVE
BUFFER ON EITHER SIDE FOR THE WARNING TIME.
AS FAR AS THE HEAVY SNOW THREAT... DID NOT STRAY TOO MUCH FROM
PREVIOUS FCST. CONVECTION/LIGHTNING STRIKES NOW BEING OBSERVED
ACROSS NRN IL IN THE SRN EDGE OF DEVELOPING DEFORMATION
ZONE/TROWAL. THIS FEATURE WILL ONLY INTENSIFY THIS EVENING... THEN
IT/S JUST A MATTER OF CHANGING PCPN OVER TO SNOW IN THE WARNING
AREA. IT LOOKS PRETTY WARM THROUGH 00Z... THEN RAPID DYNAMICAL
COOLING SHOULD FORCE CHANGEOVER TO HEAVY SNOW WITH ONE TO TWO INCH
PER HOUR RATES STILL LIKELY TONIGHT.
BECAUSE OF THE MARGINAL SFC TEMPS IN THE MID 30S ACROSS THE
WARNING AREA... ELEVATION WILL PROBABLY PLAY A CRITICAL ROLE IN
WHEN RAIN CHANGES TO SNOW AND ALSO IN STORM TOTAL SNOW
ACCUMULATION. HAVE ADDED IN MECOSTA COUNTY INTO THE WARNING AS
HIGHER ELEVATIONS THERE MAY RESULT IN AMOUNTS APPROACHING SIX
INCHES. HOWEVER EVEN WHERE ACCUMS DO NOT REACH SIX INCHES THE
WARNING IS PROBABLY STILL WELL JUSTIFIED DUE TO THE COMBO OF THE
HIGH WINDS AND THE SNOW.
HEAVY SYNOPTIC SNOW IN THE DEFORMATION ZONE SHOULD BE WINDING DOWN
TOWARD 12Z SAT... WITH A TRANSITION TO LAKE EFFECT/ENHANCED SNOWS.
ANOTHER 2 TO 4 INCHES IS POSSIBLE ON SATURDAY IN THE WARNING
AREA... AND ALSO FARTHER SOUTH INCLUDING THE GRR/BIV AREAS. AFTER
THE HIGH WIND WARNING EXPIRES... A WINTER WEATHER ADVISORY MAY BE
NEEDED SATURDAY FOR KENT/OTTAWA SOUTH... WHILE THE WARNING
CONTINUES IN THE NORTH.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 213 PM EST FRI MAR 2 2012
THERE ARE TWO SYSTEMS WE ARE WATCHING IN THE LONG TERM PERIOD. THE
FIRST IS THE LAKE ENHANCED SNOW SHOWERS WITH THE ARCTIC FRONT
COMING THROUGH EARLY SUNDAY MORNING THEN THE SYSTEM IN THE
WEDNESDAY TIME FRAME.
THERE IS A TRAILING NORTHERN STREAM SYSTEM THAT ROTATES ACROSS
LOWER MICHIGAN SUNDAY NIGHT ON THE NORTHERN STREAM. THIS BRINGS TO
COLDEST AIR THIS AREA HAS SEEN SINCE THE AROUND THE 12TH OF
FEBRUARY. HIGH TEMPERATURES WILL BE BELOW FREEZING SUNDAY ACROSS
JUST ABOUT ALL OF THE CWA. WITH THAT COLD AIR COMING IN I EXPECTED
ENHANCED LAKE EFFECT SNOW SHOWERS AS THERE IS GOOD UPPER AIR
SUPPORT AND DECENT LOW LEVEL WIND CONVERGENCE ON THE FRONT. SO I
HAVE HIGH POPS SUNDAY NIGHT WEST OF US-131. SNOWFALL SHOULD BE
LIMITED AS THE SNOW WILL MOSTLY HAPPEN AS THE FRONT DROPS SOUTH.
ONCE THE FRONT IS THROUGH WINDS BECOME NORTH DURING THE DAY SUNDAY
SO SNOW SHOWERS WILL MOSTLY BE NEAR THE LAKE SHORE. SUNDAY NIGHT
THE HIGH MOVES IN AND ANY SNOW SHOWERS SHOULD DIMINISH. THE UPPER
LEVEL JET CROSSING SOUTHWEST LOWER MICHIGAN EARLY MONDAY WILL
CAUSE THE INVERSION HEIGHT TO CRASH TOO... FARTHER LIMITING THE
POTENTIAL FOR SNOW SHOWERS.
HIGH PRESSURE RULES MONDAY DURING THE DAY INTO TUESDAY. THEN THE
NEXT SYSTEM DURING THE WEDNESDAY TO THURSDAY TIME FRAME. THERE ARE
BIG DIFFERENCES BETWEEN THE GFS AND ECMWF AS THE ECMWF HAS A MUCH
LARGER UPPER RIDGE OVER THE WEST COAST... CAUSING A MUCH DEEPER
TROUGH OVER THE CENTRAL UNITED STATES. THE ECMWF BRINGS EVEN
COLDER AIR IN BEHIND THAT SYSTEM THURSDAY INTO FRIDAY THAN THIS
WEEKEND. WITH THE GFS BEING MUCH FLATTER... NOT MUCH COLD AIR
FOLLOWS. GIVEN THE VARIABILITY ON THE MODELS AND THAT EVEN THE
ECMWF HAS NOT BEEN VERY CONSISTENT WITH THIS I WENT HALF WAY
BETWEEN THE TOO MODELS. FOR NOW THROUGH BOTH SUGGEST EVERY WARM
WEATHER WITH SHOWERS WEDNESDAY AHEAD OF THE COLD FRONT. THE ISSUE
STARTS THURSDAY ONCE THE COLD AIR COMES IN. WE WILL HAVE TO WATCH
THIS FOR ANOTHER POSSIBLE WINTER WEATHER EVENT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING
AFTERNOON)
ISSUED AT 651 PM EST FRI MAR 2 2012
THUNDERSTORMS WERE LIFTING NORTHEASTWARD THROUGH THE KMKG TO KGRR
TO KLAN REGION AND COULD LAST ANOTHER HOUR OR TWO. RAIN SHOULD
CHANGE TO SNOW AT KMKG BY 02Z AND KGRR BY 06Z. IFR OR LOWER
CONDITIONS ARE EXPECTED AS A BAND OF VERY HEAVY SNOW INITIALLY
IMPACTS KMKG AND COULD CLIP KGRR. FURTHER SOUTH AND EAST KJXN MAY
NOT SEE THE SNOW UNTIL AFTER 06Z. WINDS WILL BE AN IMPACT AND ALL
TAF SITES WILL SEE GUSTS OVER 30KNOTS WITH 40 KNOTS LIKELY BY 06Z.
&&
.MARINE...
ISSUED AT 445 PM EST FRI MAR 2 2012
UPGRADED THE GALE WARNING TO A STORM WARNING FOR TONIGHT AS
INTENSE LOW GOES BY. GALES STILL POSSIBLE EARLY SATURDAY BEFORE
A GRADUAL DIMINISHING TREND THROUGH SATURDAY NIGHT AND SUNDAY.
&&
.HYDROLOGY...
ISSUED AT 445 PM EST FRI MAR 2 2012
RIVER LEVELS ARE HIGH DUE TO RECENT RAINS... AND UP TO ANOTHER
INCH OF RAIN MAY FALL TONIGHT. LOCALLY HIGHER AMOUNTS ALSO
POSSIBLE. AT THIS TIME... EVEN WITH FUTURE QPF FACTORED IN... NO
SITES ARE FORECAST TO REACH OR EXCEED FLOOD STAGE. SEVERAL SITES
HOWEVER ARE IN FLOOD ADVISORIES... INCLUDING... GRAND RIVER AT
IONIA... PORTAGE RIVER NEAR VICKSBURG... GRAND RIVER AT JACKSON...
SYCAMORE CREEK AT HOLT... MAPLE RIVER AT MAPLE RAPIDS... AND
THORNAPPLE RIVER ABOVE HASTINGS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...HIGH WIND WARNING UNTIL 7 AM EST SATURDAY FOR MIZ046-051-052-
056>059-064>067-071>074.
WINTER STORM WARNING UNTIL 1 PM EST SATURDAY FOR MIZ037>040-
043>045-050.
LM...STORM WARNING UNTIL 7 AM EST SATURDAY FOR LMZ844>849.
&&
$$
UPDATE...MJS
SHORT TERM...MEADE/LAURENS
LONG TERM....WDM
AVIATION...93
MARINE...MEADE
HYDROLOGY...MEADE
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
703 PM EST FRI MAR 2 2012
.UPDATE...
ISSUED AT 651 PM EST FRI MAR 2 2012
THE MAIN AREA OF SHOWERS AND THUNDERSTORMS WAS LIFTING NORTH OF
KALAMAZOO AND BATTLE CREEK. WINDS HAVE SHIFTED AT MUSKEGON AND ARE
NOW OUT OF THE NORTH. THIS WILL HELP TO DRAW DOWN THE COLDER AIR
AND RESULT IN A CHANGE OVER TO SNOW IN MUSKEGON BY 9 PM. WINDS
HAVE NOT INCREASED YET...BUT BY 10 PM WE SHOULD BE SEEING THE
POWERFUL GUSTS DEVELOPING ALONG INTERSTATE 94.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 445 PM EST FRI MAR 2 2012
SFC LOW TO TRACK ACROSS KALAMAZOO TO SAGINAW BAY THIS EVENING
WHILE RAPIDLY DEEPENING. LATEST MSAS SHOWS IT AT PRESENTLY 990MB
IN WRN INDIANA AND THE HRR RUC HAS IT 970MB AT 07Z OVER SAGINAW
BAY. AS THE LOW PASSES BY LATER THIS EVENING LOOK FOR WIND GUSTS
APPROACHING OR EXCEEDING WARNING CRITERIA OF 50 KNOTS. THIS IS
SUPPORTED IN FCST SNDGS AND HRR WIND GUST PROGS... WITH BEST
THREAT OVER THE SRN FCST AREA. NOT AS CERTAIN NORTH OF ST JOHNS.
BEST WINDOW FOR SVR GUSTS IS ROUGHLY 04Z-08Z... BUT WILL HAVE
BUFFER ON EITHER SIDE FOR THE WARNING TIME.
AS FAR AS THE HEAVY SNOW THREAT... DID NOT STRAY TOO MUCH FROM
PREVIOUS FCST. CONVECTION/LIGHTNING STRIKES NOW BEING OBSERVED
ACROSS NRN IL IN THE SRN EDGE OF DEVELOPING DEFORMATION
ZONE/TROWAL. THIS FEATURE WILL ONLY INTENSIFY THIS EVENING... THEN
IT/S JUST A MATTER OF CHANGING PCPN OVER TO SNOW IN THE WARNING
AREA. IT LOOKS PRETTY WARM THROUGH 00Z... THEN RAPID DYNAMICAL
COOLING SHOULD FORCE CHANGEOVER TO HEAVY SNOW WITH ONE TO TWO INCH
PER HOUR RATES STILL LIKELY TONIGHT.
BECAUSE OF THE MARGINAL SFC TEMPS IN THE MID 30S ACROSS THE
WARNING AREA... ELEVATION WILL PROBABLY PLAY A CRITICAL ROLE IN
WHEN RAIN CHANGES TO SNOW AND ALSO IN STORM TOTAL SNOW
ACCUMULATION. HAVE ADDED IN MECOSTA COUNTY INTO THE WARNING AS
HIGHER ELEVATIONS THERE MAY RESULT IN AMOUNTS APPROACHING SIX
INCHES. HOWEVER EVEN WHERE ACCUMS DO NOT REACH SIX INCHES THE
WARNING IS PROBABLY STILL WELL JUSTIFIED DUE TO THE COMBO OF THE
HIGH WINDS AND THE SNOW.
HEAVY SYNOPTIC SNOW IN THE DEFORMATION ZONE SHOULD BE WINDING DOWN
TOWARD 12Z SAT... WITH A TRANSITION TO LAKE EFFECT/ENHANCED SNOWS.
ANOTHER 2 TO 4 INCHES IS POSSIBLE ON SATURDAY IN THE WARNING
AREA... AND ALSO FARTHER SOUTH INCLUDING THE GRR/BIV AREAS. AFTER
THE HIGH WIND WARNING EXPIRES... A WINTER WEATHER ADVISORY MAY BE
NEEDED SATURDAY FOR KENT/OTTAWA SOUTH... WHILE THE WARNING
CONTINUES IN THE NORTH.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 213 PM EST FRI MAR 2 2012
THERE ARE TWO SYSTEMS WE ARE WATCHING IN THE LONG TERM PERIOD. THE
FIRST IS THE LAKE ENHANCED SNOW SHOWERS WITH THE ARCTIC FRONT
COMING THROUGH EARLY SUNDAY MORNING THEN THE SYSTEM IN THE
WEDNESDAY TIME FRAME.
THERE IS A TRAILING NORTHERN STREAM SYSTEM THAT ROTATES ACROSS
LOWER MICHIGAN SUNDAY NIGHT ON THE NORTHERN STREAM. THIS BRINGS TO
COLDEST AIR THIS AREA HAS SEEN SINCE THE AROUND THE 12TH OF
FEBRUARY. HIGH TEMPERATURES WILL BE BELOW FREEZING SUNDAY ACROSS
JUST ABOUT ALL OF THE CWA. WITH THAT COLD AIR COMING IN I EXPECTED
ENHANCED LAKE EFFECT SNOW SHOWERS AS THERE IS GOOD UPPER AIR
SUPPORT AND DECENT LOW LEVEL WIND CONVERGENCE ON THE FRONT. SO I
HAVE HIGH POPS SUNDAY NIGHT WEST OF US-131. SNOWFALL SHOULD BE
LIMITED AS THE SNOW WILL MOSTLY HAPPEN AS THE FRONT DROPS SOUTH.
ONCE THE FRONT IS THROUGH WINDS BECOME NORTH DURING THE DAY SUNDAY
SO SNOW SHOWERS WILL MOSTLY BE NEAR THE LAKE SHORE. SUNDAY NIGHT
THE HIGH MOVES IN AND ANY SNOW SHOWERS SHOULD DIMINISH. THE UPPER
LEVEL JET CROSSING SOUTHWEST LOWER MICHIGAN EARLY MONDAY WILL
CAUSE THE INVERSION HEIGHT TO CRASH TOO... FARTHER LIMITING THE
POTENTIAL FOR SNOW SHOWERS.
HIGH PRESSURE RULES MONDAY DURING THE DAY INTO TUESDAY. THEN THE
NEXT SYSTEM DURING THE WEDNESDAY TO THURSDAY TIME FRAME. THERE ARE
BIG DIFFERENCES BETWEEN THE GFS AND ECMWF AS THE ECMWF HAS A MUCH
LARGER UPPER RIDGE OVER THE WEST COAST... CAUSING A MUCH DEEPER
TROUGH OVER THE CENTRAL UNITED STATES. THE ECMWF BRINGS EVEN
COLDER AIR IN BEHIND THAT SYSTEM THURSDAY INTO FRIDAY THAN THIS
WEEKEND. WITH THE GFS BEING MUCH FLATTER... NOT MUCH COLD AIR
FOLLOWS. GIVEN THE VARIABILITY ON THE MODELS AND THAT EVEN THE
ECMWF HAS NOT BEEN VERY CONSISTENT WITH THIS I WENT HALF WAY
BETWEEN THE TOO MODELS. FOR NOW THROUGH BOTH SUGGEST EVERY WARM
WEATHER WITH SHOWERS WEDNESDAY AHEAD OF THE COLD FRONT. THE ISSUE
STARTS THURSDAY ONCE THE COLD AIR COMES IN. WE WILL HAVE TO WATCH
THIS FOR ANOTHER POSSIBLE WINTER WEATHER EVENT.
&&
.AVIATION...(FOR THE 00Z TAFS THROUGH 00Z SATURDAY EVENING
AFTERNOON)
ISSUED AT 651 PM EST FRI MAR 2 2012
THUNDERSTORMS WERE LIFTING NORTHEASTWARD THROUGH THE KMKG TO KGRR
TO KLAN REGION AND COULD LAST ANOTHER HOUR OR TWO. RAIN SHOULD
CHANGE TO SNOW AT KMKG BY 02Z AND KGRR BY 06Z. IFR OR LOWER
CONDITIONS ARE EXPECTED AS A BAND OF VERY HEAVY SNOW INITIALLY
IMPACTS KMKG AND COULD CLIP KGRR. FURTHER SOUTH AND EAST KJXN MAY
NOT SEE THE SNOW UNTIL AFTER 06Z. WINDS WILL BE AN IMPACT AND ALL
TAF SITES WILL SEE GUSTS OVER 30KNOTS WITH 40 KNOTS LIKELY BY 06Z.
&&
.MARINE...
ISSUED AT 445 PM EST FRI MAR 2 2012
UPGRADED THE GALE WARNING TO A STORM WARNING FOR TONIGHT AS
INTENSE LOW GOES BY. GALES STILL POSSIBLE EARLY SATURDAY BEFORE
A GRADUAL DIMINISHING TREND THROUGH SATURDAY NIGHT AND SUNDAY.
&&
.HYDROLOGY...
ISSUED AT 445 PM EST FRI MAR 2 2012
RIVER LEVELS ARE HIGH DUE TO RECENT RAINS... AND UP TO ANOTHER
INCH OF RAIN MAY FALL TONIGHT. LOCALLY HIGHER AMOUNTS ALSO
POSSIBLE. AT THIS TIME... EVEN WITH FUTURE QPF FACTORED IN... NO
SITES ARE FORECAST TO REACH OR EXCEED FLOOD STAGE. SEVERAL SITES
HOWEVER ARE IN FLOOD ADVISORIES... INCLUDING... GRAND RIVER AT
IONIA... PORTAGE RIVER NEAR VICKSBURG... GRAND RIVER AT JACKSON...
SYCAMORE CREEK AT HOLT... MAPLE RIVER AT MAPLE RAPIDS... AND
THORNAPPLE RIVER ABOVE HASTINGS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...HIGH WIND WARNING UNTIL 7 AM EST SATURDAY FOR MIZ046-051-052-
056>059-064>067-071>074.
WINTER STORM WARNING UNTIL 1 PM EST SATURDAY FOR MIZ037>040-
043>045-050.
LM...STORM WARNING UNTIL 7 AM EST SATURDAY FOR LMZ844>849.
&&
$$
UPDATE...MJS
SHORT TERM...MEADE
LONG TERM....WDM
AVIATION...93
MARINE...MEADE
HYDROLOGY...MEADE
AREA FORECAST DISCUSSION
NWS GLASGOW MT
857 PM MST FRI MAR 2 2012
.SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH SUNDAY...
LOOKS LIKE A QUIET NIGHT IN REGARDS TO PRECIP AND WIND THANKS TO A
SURFACE HIGH PRESSURE CELL IN THE AREA. HOWEVER MID AND UPPER LEVEL
MOISTURE SHOULD CONTINUE TO SPILL INTO THE AREA ON THE NW FLOW.
OTHERWISE...TEMPERATURES SHOULDN/T DROP TOO MUCH AS A STATIONARY
FRONT OVER CENTRAL MONTANA BEGINS TO MOVE NORTHEAST AND CLOUDS
INCREASE. TEMPS HAVE ALREADY DROPPED BELOW THEIR RESPECTIVE FORECAST
IN THE NE HALF OF THE CWA...SO WILL HAVE TO LOWER HERE. JAMBA
PREVIOUS DISCUSSION...
SYNOPTIC SET UP... A TROUGH IS TRANSITIONING FROM THE NORTHERN
PLAINS INTO THE GREAT LAKES. COLDEST AIR OF THE NORTHERN
HEMISPHERE SITS OVER THE NORTHERN HUDSON BAY. TO THE WEST A RIDGE
EXTENDS FROM UP THE COAST OF CALIFORNIA INTO CENTRAL BRITISH
COLUMBIA. ANOTHER LONG WAVE TROUGH IS MOVING OUT OF THE BEARING
SEA INTO THE GULF OF ALASKA.
THIS AFTERNOON AND EVENING... MONTANA WILL BE WEDGED IN NORTHWEST
FLOW BETWEEN THE EXITING TROUGH AND ENTERING RIDGE WHICH WILL
PROVIDE OCCASIONAL INSTABILITY. ACROSS THE SOUTHWEST SECTIONS OF
THE CWA THE HRRR MODEL ALONG WITH BOTH VERSIONS OF THE WRF ARE
POINTING TOWARDS AFTERNOON AND LATE EVENING INSTABILITY SHOWERS.
HAVE THROWN UP LIMITED POPS FOR THESE EVENTS BEING THAT THEY ARE A
BIT ON THE CHAOTIC SIDE. HOWEVER... AFTERNOON SHOWERS SEEM MORE
LIKELY DUE TO SIMILAR ACTIVITY TO YESTERDAY AFTERNOON WITH
CLEARING SKIES AND NO SNOW COVER.
SATURDAY MORNING THROUGH SUNDAY... UPPER LEVEL RIDGE TO THE WEST
WILL CONTINUE TO FILTER INTO THE REGION AND ASSERT INCREASING
DOMINANCE. 850 MB TEMPERATURES ARE ANTICIPATED TO RISE FROM RANGE
OF -9*C TO -2*C UP INTO THE POSITIVE SINGLE DIGITS CELSIUS. SKIES
WILL BE BE MOSTLY CLOUDY INITIALLY BUT SHOULD BE DECREASING OVER
THE NEXT FEW DAYS. A LEE SIDE MOUNTAIN TROUGH WILL SET UP AT THE
SURFACE TONIGHT AND BEGIN WAFFLING BACK AND FORTH ACROSS THE CWA
THROUGH SUNDAY. THIS WILL HELP TO TRIGGER INSTABILITY SHOWERS EACH
AFTERNOON AND EVENING. ON SUNDAY THE TROUGH WILL WANDER FAR ENOUGH
EASTWARD LATE IN THE DAY DUE TO DOWNSLOPE WARMING THAT IT WILL
EXIT THE AREA BRINGING TOTALLY DRY CONDITIONS. GAH
.LONG TERM...SUNDAY NIGHT THROUGH FRIDAY...
FAIR CONFIDENCE FOR THE EARLY PERIODS OF THE EXTENDED BUT DROPS
CONSIDERABLY BY MIDWEEK...WITH LOW CONFIDENCE INTO NEXT WEEKEND.
UPPER RIDGE OVER THE REGION MONDAY BREAKS DOWN AS AN UPPER TROF
PUSHES THROUGH THE PACIFIC NORTHWEST. STILL SOME QUESTIONS
REGARDING THIS TROF AND HOW MUCH IT DIGS SOUTHWEST AS IT PUSHES
THROUGH THE GREAT BASIN. STILL EXPECT SOME SNOW AS A STRONG COLD
FRONT MOVES ACROSS THE STATE MONDAY NIGHT/TUESDAY BUT HEAVIEST
AMOUNTS CURRENTLY EXPECTED IN SOUTHWEST MONTANA. REMAINDER OF THE
FORECAST TRENDED TOWARD CLIMO WHICH IS SIMILAR TO A MODEL BLEND
DUE TO THE SIGNIFICANT MODEL DIFFERENCES. EBERT
PREVIOUS LONG TERM DISCUSSION...THE EXTENDED FORECAST BEGINS WITH
UPPER RIDGING IN PLACE OVER THE REGION. THE ATMOSPHERE WARMS QUITE
NICELY ACROSS CENTRAL AND EASTERN MONTANA. LONG RANGE MODELS AGREE
ON THIS AND HAVE SHOWN THIS TREND FOR THE PAST FEW DAYS FOR ABOVE
NORMAL CONFIDENCE FOR SUNDAY NIGHT THROUGH WEDNESDAY MORNING. THEN
THE EC AND GFS HEAD OFF IN DIFFERENT DIRECTIONS...THEREFORE AFTER
WEDNESDAY MORNING THE FORECAST CONFIDENCE FACTOR DROPS OFF
SIGNIFICANTLY. GOING TO SIDE MORE WITH THE GFS FAMILY OVER THE EC.
BOTH THE GFS AND EC MODELS DO SHOW SOME ODDITIES FOR THIS TIME OF
YEAR. THE OVERALL AMOUNT OF CUT OFF LOWS IN EACH MODEL AROUND THE
NORTHERN HEMISPHERE LEADS TO A VERY COMPLICATED PATTERN FOR LARGE
SCALE MODELS TO GIVE A GOOD SOLUTION THAT FAR OUT. THE ENSEMBLES
DO NOT FAVOR EITHER MODEL OR GIVE AN IDEA OF WHICH DIRECTION TO
TAKE THE FORECAST THEREFORE OPTED FOR PERSISTENCE FROM WEDNESDAY
AND BEYOND.
MONDAY WILL HIGHLIGHT ABOVE NORMAL TEMPERATURES AND SPRING LIKE
WEATHER FOR THE REGION. TUESDAY A COLD FRONT WILL PUSH THROUGH
NORTHEAST MONTANA... THE FRONTAL TIMING HAS SPED UP THEREFORE DID
TAKE TEMPERATURES DOWN A FEW DEGREES FOR THE EARLIER FRONTAL
PASSAGE. WEDNESDAY AND BEYOND... SLOW WARMING TREND TO KEEP WITH
THE PERSISTENCE TREND. PROTON
&&
.AVIATION...
GENERALLY EXPECT VFR CONDITIONS ALTHOUGH A FEW SNOW SHOWERS MAY
MOVE ACROSS THE REGION TONIGHT AND SATURDAY. FLIGHT CONDITIONS
WITH THE SNOW SHOWERS COULD DROP TO MVFR OR POSSIBLY IFR LEVELS.
RAE
&&
.GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE.
&&
$$
WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS BILLINGS MT
921 PM MST WED FEB 29 2012
.SHORT TERM...VALID FOR THU AND FRI...
A PACIFIC COLD FRONT IS MOVING EAST ACROSS THE REGION THIS EVENING
IN ADVANCE OF A SHORT WAVE TROUGH. FRONTAL PASSAGE IN BILLINGS WAS
BETWEEN 02 AND 03 UTC. A BROKEN BAND OF SHOWERS HAS BEEN FOLLOWING
THE FRONT THANKS TO SOME MID-LEVEL INSTABILITY AND MODEST FORCING.
THIS SCENARIO HAS PRODUCED SOME BRIEF REDUCTIONS IN VISIBILITY FOR
PLACES LIKE HARLOWTON...BUT ON ITS SOUTH END AROUND BIG TIMER...IT
APPEARS THAT THE LOW-LEVEL AIR MASS WAS TOO DRY FOR MORE THAN SOME
VIRGA. THE 00 UTC NAM AND RECENT HRRR RUNS SUPPORT THESE TRENDS IN
THAT THEY PRODUCE MOST OF THEIR PRECIPITATION TO THE NORTH OF I-94
IN ASSOCIATION WITH THE BETTER 500-300 Q-VECTOR CONVERGENCE. BRIEF
SNOW SHOWERS ARE STILL LIKELY IN THOSE AREAS...BUT WE WILL UTILIZE
POPS IN THE 30 TO 60 PERCENT RANGE TO REFLECT THE SCATTERED NATURE
OF THE PRECIPITATION. AS OF 04 UTC...CLOUD TOPS ARE COOLING TO THE
EAST OF BILLINGS...AND A BRIEF SNOW SHOWER OCCURRED DOWNTOWN. THUS
WE WILL CONTINUE WITH SOME 20 TO 30 POPS ALL THE WAY DOWN INTO THE
SOUTHEAST PART OF MT AND SHERIDAN COUNTY WY.
OTHER THAN MINOR ADJUSTMENTS TO POPS BASED ON THE LATEST TRENDS...
THE ONLY OTHER CHANGES TO THE FORECAST WERE TO 1/ ADJUST WINDS UP
A BIT BEHIND THE FRONT IN SOUTHEAST MT...AND 2/ TO INCREASE LOWS A
FEW DEGREES IN THOSE SAME AREAS GIVEN THE INCREASING MIXING BEHIND
THE FRONT BEFORE 12 UTC. SCHULTZ
.LONG TERM...VALID FOR SAT...SUN...MON...TUE...WED...
CHANGES WERE RELATIVELY MINOR FOR THE EXTENDED PERIOD...AND MAINLY
ALONG LINES EXPECTED AFTER MORNING BRIEFING...AS MODELS REMAIN IN
PRETTY GOOD AGREEMENT OVERALL. TIMING ISSUES SEEM TO BE IMPROVING
IN THE 12Z RUNS...WITH COLD FRONT INTO THEN REGION MONDAY NIGHT.
MODELS DIVERGE AGAIN BY WEDNESDAY NIGHT WITH DEPARTURE OF COLD
AIR.
UNSTABLE NORTHWEST FLOW CONTINUES OVER THE REGION SATURDAY...WITH MAINLY
WRAP AROUND TYPE REMNANT SHOWERS FOLLOWING PASSAGE OF TROF AXIS.
KEPT SLIGHT POPS ACROSS THE PLAINS AT THIS TIME...AND HIGHER
CHANCES IN MOUNTAINS...WITH CONTINUED PACIFIC FLOW INTO HIGH
TERRAIN. UPPER LEVEL RIDGE BUILDS INTO THE REGION FOR
SUNDAY...CLEARING OUT ANY CHANCE FOR PRECIP. DID WARM UP TEMPS TO
MID TO UPPER 50S FOR SUNDAY...UNDER THE RIDGE. THIS IS STILL A
TOUCH UNDER GUIDANCE...AND THINK COULD BE A BIT WARMER...BUT
SHOULD BE CLOSE IF TIMING CONTINUES IN THE SAME MANNER.
ALSO...ALTHOUGH GUIDANCE INDICATES SUNDAY TO WARMER THAN
MONDAY...IT LOOKS LIKE MONDAY COULD BE WARMER WITH POTENTIAL OF A WARMER
START TO THE DAY...AND SIGNIFICANT PREFRONTAL WARMING THROUGH
MONDAY. SO RAISED TEMPS TO 60 AROUND KBIL...AND UPPER 50S IN MOST
OTHER AREAS. THE COLD FRONT AND ASSOCIATED TROF SHOULD PUSH INTO
THE REGION TUESDAY MORNING...WHICH SHOULD RESULT IN COOLER TEMPS
TUESDAY...AND SCATTERED PRECIP ACROSS THE REGION. DID RAISE POPS
IN THE UPSLOPE AREAS ALONG THE BEARTOOTH/ABSAROKA...AND PRYOR
MOUNTAINS. MODELS DIVERGE SIGNIFICANTLY AFTER TUESDAY
NIGHT...WITH EC FAVORING THE CONTINUATION OF COLD AND ACTIVE
WEATHER...AS A BROAD TROF STALLS OVER EASTERN MONTANA. THE GFS
HOWEVER FAVORS SHALLOW RIDGING. SO HAVE CONTINUED WITH INHERITED
NUMBERS FOR NOW...SEEING NO TREND EITHER DIRECTION. AAG
&&
.AVIATION...
DISTURBANCE TRACKING THROUGH THE REGION IS BRINGING SNOW SHOWERS
WITH SHORTLIVED MVFR CONDITIONS POSSIBLE. BETTER CHANCE FOR
PERSISTENT SNOW SHOWERS CAUSING REDUCTIONS BELOW MVFR IS POSSIBLE
THURSDAY AFTERNOON. BORSUM
&&
.PRELIMINARY POINT TEMP/POPS...
THU FRI SAT SUN MON TUE WED
-----------------------------------------------------------
BIL 024/040 020/037 026/044 030/058 033/060 030/041 023/038
53/J 32/J 22/W 20/B 01/B 22/J 21/B
LVM 021/034 014/033 017/039 025/052 028/056 026/037 019/033
74/J 32/J 24/J 21/N 11/N 24/J 22/J
HDN 021/040 018/037 021/043 028/057 030/060 029/043 021/039
53/J 44/J 22/J 20/B 01/B 23/W 21/B
MLS 022/039 017/033 020/040 027/053 031/058 029/041 020/039
41/B 23/J 22/J 20/B 01/U 22/W 21/B
4BQ 021/037 016/032 018/037 025/053 028/055 027/041 019/038
21/B 34/J 22/J 20/B 01/U 12/W 22/J
BHK 019/036 013/025 013/034 021/047 027/053 026/037 017/038
31/B 13/J 11/N 21/B 01/U 12/W 21/B
SHR 018/036 015/033 016/038 023/053 027/056 027/040 018/039
22/J 33/J 22/J 21/B 01/U 22/J 22/J
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...NONE.
WY...NONE.
&&
$$
WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1159 PM EST WED FEB 29 2012
.SYNOPSIS...
WEAKENING LOW PRESSURE OVER IOWA WILL DRIFT EAST TO LAKE ONTARIO BY
THURSDAY MORNING...BEFORE REDEVELOPING OFF THE NEW ENGLAND COAST ON
THURSDAY EVENING. THIS SYSTEM WILL BRING MAINLY RAIN TO WESTERN AND
CENTRAL NEW YORK WITH MIXED WINTRY PRECIPITATION TO THE EASTERN LAKE
ONTARIO REGION TONIGHT...WHICH WILL THEN TAPER OFF FROM WEST TO EAST
ON THURSDAY. EXPECT ANOTHER STORM SYSTEM TO AFFECT OUR REGION TOWARD
THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH THURSDAY/...
THROUGH 1100 PM...LOW PRESSURE ACROSS EASTERN MICHIGAN WILL
SLOWLY LIFT TO THE EASTERN GREAT LAKES REGION OVERNIGHT. STEADY
RAIN ASSOCIATED WITH MID-LEVEL WARM AIR ADVECTION HAS EXITED THE
REGION...WITH MOST LOCATIONS NORTH OF THE THRUWAY EITHER DRY...OR
WITH SOME DRIZZLE.
THE BIGGER ISSUE TONIGHT IS AN AREA OF CONVECTION WHICH HAS
DEVELOPED UPSTREAM. 12Z RUNS OF THE NAM/RGEM AND THE 01Z HRRR HAVE
CONSISTENTLY SHOWN SHOWERS EXPANDING AND LIFTING ACROSS WESTERN
NEW YORK BETWEEN 03Z AND 09Z...THEN EAST OF LAKE ONTARIO AFTER 09Z.
AT 1100 PM...THERE IS STILL SOME LIGHTNING WITH THESE SHOWERS.
THIS WILL GRADUALLY DIMINISH AS THE SHOWERS LIFT NORTH...BUT DON/T
BE SURPRISES IF THERE IS A RUMBLE OF THUNDER OR TWO IN BUFFALO
METRO AS THESE SHOWERS MOVE THROUGH AROUND MIDNIGHT. RADAR TRENDS
ARE SUPPORTING THE HRRR WHICH SPLITS THIS CONVECTION AS IF THE
CHAUTAUQUA RIDGE WAS A WEDGE. ONE AREA OF HEAVIER SHOWERS SHOULD
SLIDE OFF TO THE EAST ALONG THE NY/PA LINE. THE OTHER AREA SHOULD
LIFT ACROSS BUFFALO METRO...THEN FLATTEN OUT AS IT TRACKS
NORTHEAST ACROSS LAKE ONTARIO.
TOWARD DAYBREAK...THIS AREA SHOULD TRACK EAST OF LAKE ONTARIO INTO
COLDER AIR. EXPECT A NE FLOW TO MAINTAIN DOWN THE SAINT LAWRENCE
VALLEY...WHICH WILL KEEP SURFACE TEMPERATURES NEAR FREEZING.
MEANWHILE...THE 00Z NAM/RGEM ARE NOW SUGGESTING A NEAR ISOTHERMAL
SOUNDING ALONG THE FREEZING LINE AT WATERTOWN. TO INTERIOR
SECTIONS...THIS WILL BRING A DECENT SNOW BURST FOR THE THURSDAY
MORNING COMMUTE...WITH A QUICK 2 TO 4 INCHES. NEAR THE LAKE
ONTARIO SHORE...AND SOUTH ACROSS OSWEGO COUNTY IT WILL BE CLOSE.
EXPECT SOME RAIN OR MIXED PRECIPITATION TO TREND TO SNOW...THOUGH
THIS SHOULD LIMIT ACCUMULATION. BECAUSE OF THIS...UPPED SNOW
FORECASTS FOR THURSDAY MORNING. OTHERWISE...EXPECT AREAS OF FREEZING
DRIZZLE EAST OF LAKE ONTARIO FOR THE REMAINDER OF THE NIGHT.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/...
BROAD TROUGHINESS IN THE LONGWAVE PATTERN WILL BE FOUND OVER THE
UNITED STATES AND SOUTHERN CANADA AT THE START OF THIS PERIOD...BUT
AS WE HEAD INTO THE WEEKEND...THIS FLOW WILL BECOME MUCH MORE
AMPLIFIED. THE PATTERN CHANGE WILL COME AS A RESULT OF A
PARTICULARLY VIGOROUS SHORTWAVE THAT WILL MOVE FROM THE BEARING SEA
AND `DOWN THE CHUTE` ALONG THE WEST COAST TO THE INTERMOUNTAIN
REGION...WITH AN ANOMALOUSLY STRONG (+3 STD) H25 JET DIGGING A
DEEPER TROUGH IN THE PROCESS. ADDITIONAL ENERGY POURING INTO THE
TROUGH WILL LEAD TO FURTHER AMPLIFICATION WHILE IT WILL PROGRESS
ACROSS THE COUNTRY. THIS WILL EVENTUALLY LEAD TO A CHANGE TO COLDER
WEATHER FOR THE GREAT LAKES REGION...BUT NOT UNTIL THE WEEKEND AND
EARLY NEXT WEEK. TIME TO SCALE DOWN AND GET SOME DETAILS.
AS ONE SHORTWAVE EXITS ACROSS NEW ENGLAND THURSDAY NIGHT...MID LEVEL
RIDGING WILL TEMPORARILY BUILD ACROSS THE OHIO VALLEY AND GREAT
LAKES WHILE A SFC HIGH WILL MOVE ACROSS THE FORECAST AREA. WHILE
THERE MAY BE SOME LEFTOVER RAIN AND WET SNOW SHOWERS EARLY (MAINLY
OVER THE NORTH COUNTRY)...INCREASING SUBSIDENCE AND MID LEVEL DRYING
WILL PROVIDE THE VAST MAJORITY OF THE AREA WITH PCPN FREE WEATHER.
THE SUBSEQUENT CLEARING WILL BE SLOW TO TAKE PLACE THOUGH...AS A
STRONG SUBSIDENCE INVERSION AND WEAK LOW LEVEL FLOW SHOULD BE
INEFFECTIVE AT CLEARING OUT THE LOW LEVEL MOISTURE. BOTTOM LINE IS
THAT LITTLE IF ANY CLEARING IS EXPECTED FOR THE OVERNIGHT.
ON FRIDAY...WARM ADVECTION WILL QUICKLY SET UP OVER THE FORECAST
AREA AS THE EXITING HIGH PRESSURE OVER THE GULF OF THE ST LAWRENCE
WILL COMBINE WITH A DEEPENING SFC LOW OVER THE LOWER OHIO VALLEY TO
ESTABLISH A STRENGTHENING SOUTHERLY FLOW. THIS PROCESS WILL HELP TO
SCOUR OUT THE LOW LEVEL MOISTURE...BUT IT WILL ALSO LEAD TO AN
INCREASE IN MID AND HIGH LEVEL MOISTURE. IT WILL ESSENTIALLY BE A
RACE WITHIN THE PROCESS TO SEE IF ANY ONE AREA EXPERIENCES MUCH
SUNSHINE. EITHER WAY...VERY MILD CONDITIONS WILL BE FOUND OVER THE
WESTERN COUNTIES AS NEAR SFC TEMPS SHOULD AT LEAST BE ABLE TO
MODERATE INTO THE MID AND UPPER 40S...IF NOT THE LOWER 50S. THE
WARMEST SITES WILL BE IN THE SRN TIER VALLEYS AND POSSIBLY THE
GENESEE VALLEY. THE NAM BASED MET GUIDANCE LOOKED UNREASONABLY
CHILLY...SO USED A BLEND OF THE MAV AND SREF BASED VALUES SITES EAST
OF LK ONTARIO WILL STAY CLOSER TO SEASONABLE LEVELS WITH READINGS
CLOSER TO 40.
THE ROBUST SHORTWAVE MENTIONED IN THE OPENING OF THIS SHORT TERM
DISCUSSION WILL ROUND THE BASE OF THE PROGRESSIVE H5 TROUGH FRIDAY
NIGHT...HELPING TO FURTHER DEEPEN THE STRONG SFC LOW THAT WILL BE
LIFTING NORTHEAST OUT OF THE OHIO VALLEY. THERE ARE DIFFERENCES
BETWEEN THE TWO MOST TRUSTED MEDIUM RANGE MODELS AT THIS POINT IN
THE EXACT TRACK AND STRENGTH OF THIS SFC LOW...BUT IN EITHER CASE A
NOTABLE LOW PRESSURE SYSTEM WILL LIFT BY TO THE WEST OF OUR FORECAST
AREA LATER FRIDAY NIGHT AND SATURDAY. WILL NOT BORE YOU WITH THE
MODEL DIFFERENCES FROM THIS RANGE BUT TO SAY THAT THE RESULTING
WEATHER WILL BASICALLY COME DOWN TO PARTS OF THE REGION EXPERIENCING
ADVISORY CRITERIA WINDS VERSUS POSSIBLE LOW END WARNING WINDS.
THE STRONG WINDS WILL COME IN TWO DISTINCT SHOTS. THE FIRST ROUND
WILL BE FRIDAY NIGHT IN ASSOCIATION WITH A 60-70KT LOW LEVEL
SOUTHERLY JET THAT WILL BE FOUND IN ADVANCE OF A COLD FRONTAL
BOUNDARY. THESE WINDS WILL POSE A THREAT ACROSS THE HIGHER TERRAIN
OF OUR FORECAST AREA...AND ALSO ALONG THE LAKE ERIE LAKESHORE WHERE
A FAVORABLE SOUTH TO SOUTHEAST LOW LEVEL FLOW WILL MAXIMIZE A
DOWNSLOPING COMPONENT. THE SECOND TIME FRAME OF CONCERN WILL BE IN
THE IMMEDIATELY WAKE OF THE COLD FRONTAL PASSAGE SATURDAY MORNING
WHEN STRONG COLD ADVECTION AND A TIGHT SFC PRESSURE GRADIENT WILL
PRODUCE A MORE BROAD BRUSH OF STRONG WINDS...MAINLY OVER THE WESTERN
COUNTIES AWAY FROM THE FINGER LAKES. DETAILS FOR EITHER THREAT WILL
BE WORKED OUT IN LATER PACKAGES AS CONFIDENCE IN THE FORECAST TRACK
OF THE SFC LOW INCREASES.
IN TERMS OF PCPN...NEAR 100M HGT FALLS FRIDAY NIGHT WILL COMBINE
WITH STRONG JET INDUCED LIFT FROM AN APPROACHING 150KT H25 JET AND
IMPRESSIVE LOW LEVEL CONVERGENCE AHEAD OF THE COLD FRONT TO PRODUCE
WIDESPREAD RAIN SHOWERS AND POSSIBLY A FEW THUNDERSTORMS. BUFKIT NAM
OVERVIEWS SUGGEST IMPRESSIVE 200-500 J/KG`S WORTH OF ELEVATED
CAPE...AND GIVEN THE STRENGTH OF THE SYNOPTIC FORCING AND ASSOCIATED
WIND FIELDS...THIS SCENARIO WOULD CERTAINLY ENCOURAGE SOME GUSTY
THUNDERSTORM DEVELOPMENT. WHILE THERE MAY BE SOME SHOWERS EARLY
THURSDAY NIGHT FROM THE ISENTROPIC LIFT...THE DEEPER CONVECTION
(STORMS) AND HEAVIER PCPN WILL LIKELY WAIT UNTIL LATER FRIDAY NIGHT
OR EVEN EARLY SATURDAY MORNING. AGAIN...THE DETAILS WILL HAVE TO BE
HAMMERED OUT IN LATER PACKAGES AS THE TIMING OF THE FRONTAL PASSAGE
IS DIRECTLY LINKED TO THE TRACK/STRENGTH OF THE AFOREMENTIONED SFC
LOW.
WHILE SATURDAY MAY OPEN UP WITH SOME GUSTY SHOWERS (ESP EAST OF LK
ONT)...THE DAY SHOULD BE LARGELY DRY AS STRONG SUBSIDENCE ASSOCIATED
WITH LOW LEVEL RIDGING WILL BE FOUND IN THE WAKE OF THE COLD FRONT.
AGAIN...THE MAIN CONCERN FOR SATURDAY WILL BE THE POTENTIAL FOR
STRONG WINDS. THIS THREAT WILL BE HIGHLIGHTED IN THE HAZARDOUS
WEATHER OUTLOOK PRODUCT.
THE WINDS WILL SUBSIDE DURING WHAT SHOULD BE AN UNEVENTFUL SATURDAY
NIGHT AS THE BASE OF THE DIGGING H5 TROUGH WILL SETTLE OVER THE
LOWER GREAT LAKES AND UPPER OHIO VALLEY. H85 TEMPS WILL DROP TO ARND
-8 TO -10C BY DAYBREAK...AND WHILE THIS WOULD BE JUST BARELY COLD
ENOUGH TO INITIATE A LAKE RESPONSE...LOW LEVEL RIDGING AND A FAIR
AMOUNT OF MID LEVEL DRY AIR SHOULD DETER ANYTHING MORE THAN SOME
LAKE INDUCED CLOUDINESS EAST OF BOTH LAKES.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
THERE IS HIGH CONFIDENCE DURING THIS PERIOD THAT NEAR TO BELOW
NORMAL TEMPERATURES WILL ONCE AGAIN MODERATE TO MUCH ABOVE NORMAL
LEVELS AS THE DEEP LONGWAVE TROUGH OVER THE GREAT LAKES WILL GIVE
WAY TO A PROGRESSIVE RIDGE. NOT ONLY WILL SIGNIFICANT RIDGING BUILD
ALONG THE EAST COAST BY MID WEEK...BUT A DEEP PACIFIC BASED FLOW
WILL BE IN PLACE ACROSS THE COUNTRY UP TO THIS POINT.
FOR SUNDAY AND SUNDAY NIGHT...THE BASE OF A DEEP H5 TROUGH WILL
CROSS THE LOWER GREAT LAKES WHILE A SECONDARY SFC COLD FRONT WILL
DROP ACROSS NEW YORK STATE. THIS WILL ALLOW H85 TEMPS TO PLUNGE TO
BETWEEN -12 AND -16C...WITH SYNOPTICALLY INDUCED SNOW SHOWERS SUNDAY
GIVING WAY TO SOME NUISANCE LAKE EFFECT SNOW SHOWERS SUNDAY NIGHT. I
SAY NUISANCE BECAUSE IT IS LIKELY THAT A CAPPING SUBSIDENCE
INVERSION WILL GREATLY LIMIT SNOW ACCUMS.
ON MONDAY...EXPANSIVE HIGH PRESSURE STRETCHING FROM THE GREAT LAKES
TO THE GULF WILL SLIDE EAST ACROSS THE REGION. WHILE THE LOWERING
SUBSIDENCE INVERSION WILL FURTHER CHOKE OFF ANY LAKE EFFECT...H85
TEMPS AVG -12C AND A WEAK NORTHERLY UPSLOPE FLOW WILL PROBABLY KEEP
A FAIR AMOUNT OF CLOUDS AROUND AND POSSIBLY SOME VERY LIGHT SNOW
SHOWERS. THIS WILL MAINLY BE THE CASE FOR SITES SOUTH OF LK
ONTARIO...WITH THE NORTH COUNTRY LIKELY HAVING THE BEST CHANCES OF
EXPERIENCING ANY SUNSHINE.
THE LARGE SFC HIGH WILL DRIFT EAST ON TUESDAY AND WEDNESDAY WHILE A
PROGRESSIVE RIDGE WILL BUILD ACROSS THE REGION. THIS WILL LEAD TO
TWO SUNNY DAYS ACROSS OUR REGION WITH A NOTICEABLE DAY TO DAY
WARMING TREND AS H85 TEMPS JUMP TO BETWEEN +4 AND +8C.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
LOW PRESSURE AND AN ASSOCIATED UPPER LEVEL DISTURBANCE WILL SLOWLY TRACK
FROM EASTERN MICHIGAN TO EASTERN GREAT LAKES REGION OVERNIGHT.
OVERNIGHT...EXPECT VARIABLE CONDITIONS ACROSS THE REGION...WITH
MVFR THE MOST COMMON. THERE MAY BE A BRIEF LOWERING TO IFR OR
LOWER AT BUF/IAG/JHW AS THE SURFACE LOW PASSES AND WINDS CALM.
ALSO...THERE IS STILL SOME ELEVATED CONVECTION ACROSS WESTERN NEW
YORK...WITH THIS EXPECTED TO DIMINISH.
STEADY RAIN SHOWERS WILL LIFT TO THE NORTHEAST LATER
TONIGHT...ENCOUNTERING COLDER AIR. PRECIPITATION TYPE WILL BE
CHALLENGING AT ART AS THIS MOVES IN...WITH SNOW APPEARING THE MOST
LIKELY FORM...THOUGH FREEZING RAIN OR RAIN ARE ALSO POSSIBLE. THIS
SHOULD GRADUALLY EXIT EAST ON THURSDAY...WITH OTHERWISE MVFR
CONDITIONS FOR MOST OF THE DAY.
OUTLOOK...
THURSDAY NIGHT...MAINLY MVFR.
FRIDAY...GENERALLY VFR.
SATURDAY...MVFR WITH RAIN SHOWERS LIKELY.
SUNDAY AND MONDAY...VFR/MVFR WITH SCATTERED SNOW SHOWERS.
&&
.MARINE...
BASED ON THE 00Z NAM/RUC FORECASTS...AND CONSIDERING THE TRACK OF
THE SURFACE LOW...OPTED TO ISSUE A SMALL CRAFT ADVISORY FOR LAKE
ERIE. EXPECT A 3 TO 6 HOUR PERIOD OF 20 TO 25 KNOT WINDS IN A
SOUTHWEST FLOW THURSDAY MORNING.
EAST TO SOUTHEAST WINDS ALONG THE WESTERN SHORES OF LAKE ONTARIO
WILL PRODUCE SMALL CRAFT ADVISORY CONDITIONS FOR THE OVERNIGHT HOURS
AS A WARM FRONT REMAINS DRAPED ACROSS THE LAKE ONTARIO BASIN. ONCE
THE LOW PRESSURE CENTER PASSES BY LATE TONIGHT/EARLY THURSDAY
MORNING...WINDS WILL QUICKLY VEER TO SOUTHWEST AND PICK UP
AGAIN...PARTICULARLY ON LAKE ERIE WHERE ADDITIONAL SMALL CRAFT
ADVISORIES SHOULD EVENTUALLY BECOME NECESSARY.
&&
.CLIMATE...
A REMARKABLE MILD WINTER CONTINUED INTO FEBRUARY WITH MONTHLY
TEMPERATURES AVERAGING OVER 5 DEGREES ABOVE NORMAL FOR A 4TH
CONSECUTIVE MONTH. VERY FEW RECORD HIGHS WERE SET IN THIS 4 MONTH
STRETCH...RATHER JUST A PERSISTENT MILD PATTERN THROUGH THE WINTER.
FOR THE DECEMBER-JANUARY-FEBRUARY TIME FRAME THE LONGEST STRETCH OF
SUB FREEZING TEMPERATURES WAS ONLY 4 DAYS FOR BOTH BUFFALO AND
ROCHESTER (JAN 18-21). NO OTHER STRETCH WAS LONGER THAN 2
DAYS...IMPRESSIVE CONSIDERING BUFFALO AND ROCHESTER AVERAGES 39
DAYS BELOW FREEZING IN THE DECEMBER THROUGH FEBRUARY TIMEFRAME.
FOR FEBRUARY BUFFALO HAD 25 DAYS REACHING OR EXCEEDING THE FREEZING
MARK...TIED WITH 1998 FOR GREATEST NUMBER OF DAYS IN THE MONTH OF
FEBRUARY REACHING OR EXCEEDING 32F. ROCHESTER HAD 25 SUCH DAYS AS
WELL...THE GREATEST EVER IN THE MONTH OF FEBRUARY.
WHILE BUFFALO HAD MINIMAL SNOW IN FEBRUARY WITH JUST 9.6 INCHES
FALLING...ROCHESTER DID FAIR BETTER UNDER SEVERAL LAKE EFFECT SNOW
BANDS WHICH HELPED BRING 26.8 INCHES OF SNOW TO THE ROCHESTER
AIRPORT FOR FEBRUARY. IN BUFFALO THE DJF SNOWFALL OF 34.2 INCHES IS
THE 4TH LOWEST SINCE THE MOVE TO THE AIRPORT...WITH 25.8 INCHES IN
THE WINTER OF 1947-48 HAVING THE LEAST TOTAL (25.8 INCHES).
DAYS WITH SNOW COVER WAS LACKING ACROSS THE REGION THIS WINTER.
BUFFALO HAD ONLY 22 DAYS IN DJF WITH AN INCH OR MORE OF SNOW ON THE
GROUND. THIS IS TIED FOR 4TH LOWEST IN 119 YEARS OF RECORD
KEEPING...AND 2ND LOWEST SINCE RECORD KEEPING MOVED TO THE AIRPORT.
THE LOWEST DJF DAYS WITH ONE INCH OR MORE OF SNOW ON THE GROUND ARE:
1931-32 (16) 1948-49 (18) AND 1936-37 (20). ROCHESTER ALSO HAD A
LACK OF DAYS WITH SNOW COVERING THE GROUND...ONLY 25 DAYS HAVING AT
LEAST AN INCH OF SNOW ON THE GROUND. IN 86 YEARS OF ROCHESTER RECORD
ONLY THE SEASON 1932-33 HAD A LOWER TOTAL...WITH 21 DAYS.
FOR THE ENTIRE WINTER SEASON (JULY-JUNE)...BUFFALO CAN FINISH NO
HIGHER THAN 3RD PLACE ALL-TIME FOR LACK OF SNOW...AND ROCHESTER
WHICH HAS FAIRED BETTER THIS WINTER CAN FINISH NO HIGHER THAN 10TH
PLACE. BELOW IS A TABLE FOR BUFFALO FOR LEAST SNOWIEST WINTERS.
RANK SEASON WINTER SNOWFALL
(INCHES)
1 1889-90 22.4
2 1918-19 25.0
3 1921-22 39.8
4 1948-49 40.1
5 1947-48 42.1
TO DATE SNOWFALL IN BUFFALO STANDS AT 34.2 INCHES.
FOR ROCHESTER WE WILL TAKE A LOOK AT YEARS SINCE 1950 SINCE WE ARE
LIKELY OUT OF THE RUNNING FOR A TOP TEN ALL-TIME LEAST AMOUNT OF SNOW.
RANK SEASON WINTER SNOWFALL (SINCE 1950)
(INCHES)
1 1952-53 41.7
2 1994-95 56.2
3 2001-02 58.1
4 1982-83 59.9
5 1961-62 65.6
TO DATE SNOWFALL IN ROCHESTER STANDS AT 52.0 INCHES.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...WINTER WEATHER ADVISORY UNTIL 4 PM EST THURSDAY FOR NYZ006>008.
MARINE...SMALL CRAFT ADVISORY FROM 6 AM TO 5 PM EST THURSDAY FOR LEZ040-
041.
SMALL CRAFT ADVISORY UNTIL 4 AM EST THURSDAY FOR
LOZ042.
&&
$$
SYNOPSIS...WCH
NEAR TERM...APFFEL/WCH
SHORT TERM...RSH
LONG TERM...RSH
AVIATION...APFFEL
MARINE...APFFEL/WCH
CLIMATE...THOMAS
AREA FORECAST DISCUSSION
NWS BUFFALO NY
1115 PM EST WED FEB 29 2012
.SYNOPSIS...
WEAKENING LOW PRESSURE OVER IOWA WILL DRIFT EAST TO LAKE ONTARIO BY
THURSDAY MORNING...BEFORE REDEVELOPING OFF THE NEW ENGLAND COAST ON
THURSDAY EVENING. THIS SYSTEM WILL BRING MAINLY RAIN TO WESTERN AND
CENTRAL NEW YORK WITH MIXED WINTRY PRECIPITATION TO THE EASTERN LAKE
ONTARIO REGION TONIGHT...WHICH WILL THEN TAPER OFF FROM WEST TO EAST
ON THURSDAY. EXPECT ANOTHER STORM SYSTEM TO AFFECT OUR REGION TOWARD
THE END OF THE WEEK.
&&
.NEAR TERM /THROUGH THURSDAY/...
THROUGH 1100 PM...LOW PRESSURE ACROSS EASTERN MICHIGAN WILL
SLOWLY LIFT TO THE EASTERN GREAT LAKES REGION OVERNIGHT. STEADY
RAIN ASSOCIATED WITH MID-LEVEL WARM AIR ADVECTION HAS EXITED THE
REGION...WITH MOST LOCATIONS NORTH OF THE THRUWAY EITHER DRY...OR
WITH SOME DRIZZLE.
THE BIGGER ISSUE TONIGHT IS AN AREA OF CONVECTION WHICH HAS
DEVELOPED UPSTREAM. 12Z RUNS OF THE NAM/RGEM AND THE 01Z HRRR HAVE
CONSISTENTLY SHOWN SHOWERS EXPANDING AND LIFTING ACROSS WESTERN
NEW YORK BETWEEN 03Z AND 09Z...THEN EAST OF LAKE ONTARIO AFTER 09Z.
AT 1100 PM...THERE IS STILL SOME LIGHTNING WITH THESE SHOWERS.
THIS WILL GRADUALLY DIMINISH AS THE SHOWERS LIFT NORTH...BUT DON/T
BE SURPRISES IF THERE IS A RUMBLE OF THUNDER OR TWO IN BUFFALO
METRO AS THESE SHOWERS MOVE THROUGH AROUND MIDNIGHT. RADAR TRENDS
ARE SUPPORTING THE HRRR WHICH SPLITS THIS CONVECTION AS IF THE
CHAUTAUQUA RIDGE WAS A WEDGE. ONE AREA OF HEAVIER SHOWERS SHOULD
SLIDE OFF TO THE EAST ALONG THE NY/PA LINE. THE OTHER AREA SHOULD
LIFT ACROSS BUFFALO METRO...THEN FLATTEN OUT AS IT TRACKS
NORTHEAST ACROSS LAKE ONTARIO.
TOWARD DAYBREAK...THIS AREA SHOULD TRACK EAST OF LAKE ONTARIO INTO
COLDER AIR. EXPECT A NE FLOW TO MAINTAIN DOWN THE SAINT LAWRENCE
VALLEY...WHICH WILL KEEP SURFACE TEMPERATURES NEAR FREEZING.
MEANWHILE...THE 00Z NAM/RGEM ARE NOW SUGGESTING A NEAR ISOTHERMAL
SOUNDING ALONG THE FREEZING LINE AT WATERTOWN. TO INTERIOR
SECTIONS...THIS WILL BRING A DECENT SNOW BURST FOR THE THURSDAY
MORNING COMMUTE...WITH A QUICK 2 TO 4 INCHES. NEAR THE LAKE
ONTARIO SHORE...AND SOUTH ACROSS OSWEGO COUNTY IT WILL BE CLOSE.
EXPECT SOME RAIN OR MIXED PRECIPITATION TO TREND TO SNOW...THOUGH
THIS SHOULD LIMIT ACCUMULATION. BECAUSE OF THIS...UPPED SNOW
FORECASTS FOR THURSDAY MORNING. OTHERWISE...EXPECT AREAS OF FREEZING
DRIZZLE EAST OF LAKE ONTARIO FOR THE REMAINDER OF THE NIGHT.
&&
.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/...
BROAD TROUGHINESS IN THE LONGWAVE PATTERN WILL BE FOUND OVER THE
UNITED STATES AND SOUTHERN CANADA AT THE START OF THIS PERIOD...BUT
AS WE HEAD INTO THE WEEKEND...THIS FLOW WILL BECOME MUCH MORE
AMPLIFIED. THE PATTERN CHANGE WILL COME AS A RESULT OF A
PARTICULARLY VIGOROUS SHORTWAVE THAT WILL MOVE FROM THE BEARING SEA
AND `DOWN THE CHUTE` ALONG THE WEST COAST TO THE INTERMOUNTAIN
REGION...WITH AN ANOMALOUSLY STRONG (+3 STD) H25 JET DIGGING A
DEEPER TROUGH IN THE PROCESS. ADDITIONAL ENERGY POURING INTO THE
TROUGH WILL LEAD TO FURTHER AMPLIFICATION WHILE IT WILL PROGRESS
ACROSS THE COUNTRY. THIS WILL EVENTUALLY LEAD TO A CHANGE TO COLDER
WEATHER FOR THE GREAT LAKES REGION...BUT NOT UNTIL THE WEEKEND AND
EARLY NEXT WEEK. TIME TO SCALE DOWN AND GET SOME DETAILS.
AS ONE SHORTWAVE EXITS ACROSS NEW ENGLAND THURSDAY NIGHT...MID LEVEL
RIDGING WILL TEMPORARILY BUILD ACROSS THE OHIO VALLEY AND GREAT
LAKES WHILE A SFC HIGH WILL MOVE ACROSS THE FORECAST AREA. WHILE
THERE MAY BE SOME LEFTOVER RAIN AND WET SNOW SHOWERS EARLY (MAINLY
OVER THE NORTH COUNTRY)...INCREASING SUBSIDENCE AND MID LEVEL DRYING
WILL PROVIDE THE VAST MAJORITY OF THE AREA WITH PCPN FREE WEATHER.
THE SUBSEQUENT CLEARING WILL BE SLOW TO TAKE PLACE THOUGH...AS A
STRONG SUBSIDENCE INVERSION AND WEAK LOW LEVEL FLOW SHOULD BE
INEFFECTIVE AT CLEARING OUT THE LOW LEVEL MOISTURE. BOTTOM LINE IS
THAT LITTLE IF ANY CLEARING IS EXPECTED FOR THE OVERNIGHT.
ON FRIDAY...WARM ADVECTION WILL QUICKLY SET UP OVER THE FORECAST
AREA AS THE EXITING HIGH PRESSURE OVER THE GULF OF THE ST LAWRENCE
WILL COMBINE WITH A DEEPENING SFC LOW OVER THE LOWER OHIO VALLEY TO
ESTABLISH A STRENGTHENING SOUTHERLY FLOW. THIS PROCESS WILL HELP TO
SCOUR OUT THE LOW LEVEL MOISTURE...BUT IT WILL ALSO LEAD TO AN
INCREASE IN MID AND HIGH LEVEL MOISTURE. IT WILL ESSENTIALLY BE A
RACE WITHIN THE PROCESS TO SEE IF ANY ONE AREA EXPERIENCES MUCH
SUNSHINE. EITHER WAY...VERY MILD CONDITIONS WILL BE FOUND OVER THE
WESTERN COUNTIES AS NEAR SFC TEMPS SHOULD AT LEAST BE ABLE TO
MODERATE INTO THE MID AND UPPER 40S...IF NOT THE LOWER 50S. THE
WARMEST SITES WILL BE IN THE SRN TIER VALLEYS AND POSSIBLY THE
GENESEE VALLEY. THE NAM BASED MET GUIDANCE LOOKED UNREASONABLY
CHILLY...SO USED A BLEND OF THE MAV AND SREF BASED VALUES SITES EAST
OF LK ONTARIO WILL STAY CLOSER TO SEASONABLE LEVELS WITH READINGS
CLOSER TO 40.
THE ROBUST SHORTWAVE MENTIONED IN THE OPENING OF THIS SHORT TERM
DISCUSSION WILL ROUND THE BASE OF THE PROGRESSIVE H5 TROUGH FRIDAY
NIGHT...HELPING TO FURTHER DEEPEN THE STRONG SFC LOW THAT WILL BE
LIFTING NORTHEAST OUT OF THE OHIO VALLEY. THERE ARE DIFFERENCES
BETWEEN THE TWO MOST TRUSTED MEDIUM RANGE MODELS AT THIS POINT IN
THE EXACT TRACK AND STRENGTH OF THIS SFC LOW...BUT IN EITHER CASE A
NOTABLE LOW PRESSURE SYSTEM WILL LIFT BY TO THE WEST OF OUR FORECAST
AREA LATER FRIDAY NIGHT AND SATURDAY. WILL NOT BORE YOU WITH THE
MODEL DIFFERENCES FROM THIS RANGE BUT TO SAY THAT THE RESULTING
WEATHER WILL BASICALLY COME DOWN TO PARTS OF THE REGION EXPERIENCING
ADVISORY CRITERIA WINDS VERSUS POSSIBLE LOW END WARNING WINDS.
THE STRONG WINDS WILL COME IN TWO DISTINCT SHOTS. THE FIRST ROUND
WILL BE FRIDAY NIGHT IN ASSOCIATION WITH A 60-70KT LOW LEVEL
SOUTHERLY JET THAT WILL BE FOUND IN ADVANCE OF A COLD FRONTAL
BOUNDARY. THESE WINDS WILL POSE A THREAT ACROSS THE HIGHER TERRAIN
OF OUR FORECAST AREA...AND ALSO ALONG THE LAKE ERIE LAKESHORE WHERE
A FAVORABLE SOUTH TO SOUTHEAST LOW LEVEL FLOW WILL MAXIMIZE A
DOWNSLOPING COMPONENT. THE SECOND TIME FRAME OF CONCERN WILL BE IN
THE IMMEDIATELY WAKE OF THE COLD FRONTAL PASSAGE SATURDAY MORNING
WHEN STRONG COLD ADVECTION AND A TIGHT SFC PRESSURE GRADIENT WILL
PRODUCE A MORE BROAD BRUSH OF STRONG WINDS...MAINLY OVER THE WESTERN
COUNTIES AWAY FROM THE FINGER LAKES. DETAILS FOR EITHER THREAT WILL
BE WORKED OUT IN LATER PACKAGES AS CONFIDENCE IN THE FORECAST TRACK
OF THE SFC LOW INCREASES.
IN TERMS OF PCPN...NEAR 100M HGT FALLS FRIDAY NIGHT WILL COMBINE
WITH STRONG JET INDUCED LIFT FROM AN APPROACHING 150KT H25 JET AND
IMPRESSIVE LOW LEVEL CONVERGENCE AHEAD OF THE COLD FRONT TO PRODUCE
WIDESPREAD RAIN SHOWERS AND POSSIBLY A FEW THUNDERSTORMS. BUFKIT NAM
OVERVIEWS SUGGEST IMPRESSIVE 200-500 J/KG`S WORTH OF ELEVATED
CAPE...AND GIVEN THE STRENGTH OF THE SYNOPTIC FORCING AND ASSOCIATED
WIND FIELDS...THIS SCENARIO WOULD CERTAINLY ENCOURAGE SOME GUSTY
THUNDERSTORM DEVELOPMENT. WHILE THERE MAY BE SOME SHOWERS EARLY
THURSDAY NIGHT FROM THE ISENTROPIC LIFT...THE DEEPER CONVECTION
(STORMS) AND HEAVIER PCPN WILL LIKELY WAIT UNTIL LATER FRIDAY NIGHT
OR EVEN EARLY SATURDAY MORNING. AGAIN...THE DETAILS WILL HAVE TO BE
HAMMERED OUT IN LATER PACKAGES AS THE TIMING OF THE FRONTAL PASSAGE
IS DIRECTLY LINKED TO THE TRACK/STRENGTH OF THE AFOREMENTIONED SFC
LOW.
WHILE SATURDAY MAY OPEN UP WITH SOME GUSTY SHOWERS (ESP EAST OF LK
ONT)...THE DAY SHOULD BE LARGELY DRY AS STRONG SUBSIDENCE ASSOCIATED
WITH LOW LEVEL RIDGING WILL BE FOUND IN THE WAKE OF THE COLD FRONT.
AGAIN...THE MAIN CONCERN FOR SATURDAY WILL BE THE POTENTIAL FOR
STRONG WINDS. THIS THREAT WILL BE HIGHLIGHTED IN THE HAZARDOUS
WEATHER OUTLOOK PRODUCT.
THE WINDS WILL SUBSIDE DURING WHAT SHOULD BE AN UNEVENTFUL SATURDAY
NIGHT AS THE BASE OF THE DIGGING H5 TROUGH WILL SETTLE OVER THE
LOWER GREAT LAKES AND UPPER OHIO VALLEY. H85 TEMPS WILL DROP TO ARND
-8 TO -10C BY DAYBREAK...AND WHILE THIS WOULD BE JUST BARELY COLD
ENOUGH TO INITIATE A LAKE RESPONSE...LOW LEVEL RIDGING AND A FAIR
AMOUNT OF MID LEVEL DRY AIR SHOULD DETER ANYTHING MORE THAN SOME
LAKE INDUCED CLOUDINESS EAST OF BOTH LAKES.
&&
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
THERE IS HIGH CONFIDENCE DURING THIS PERIOD THAT NEAR TO BELOW
NORMAL TEMPERATURES WILL ONCE AGAIN MODERATE TO MUCH ABOVE NORMAL
LEVELS AS THE DEEP LONGWAVE TROUGH OVER THE GREAT LAKES WILL GIVE
WAY TO A PROGRESSIVE RIDGE. NOT ONLY WILL SIGNIFICANT RIDGING BUILD
ALONG THE EAST COAST BY MID WEEK...BUT A DEEP PACIFIC BASED FLOW
WILL BE IN PLACE ACROSS THE COUNTRY UP TO THIS POINT.
FOR SUNDAY AND SUNDAY NIGHT...THE BASE OF A DEEP H5 TROUGH WILL
CROSS THE LOWER GREAT LAKES WHILE A SECONDARY SFC COLD FRONT WILL
DROP ACROSS NEW YORK STATE. THIS WILL ALLOW H85 TEMPS TO PLUNGE TO
BETWEEN -12 AND -16C...WITH SYNOPTICALLY INDUCED SNOW SHOWERS SUNDAY
GIVING WAY TO SOME NUISANCE LAKE EFFECT SNOW SHOWERS SUNDAY NIGHT. I
SAY NUISANCE BECAUSE IT IS LIKELY THAT A CAPPING SUBSIDENCE
INVERSION WILL GREATLY LIMIT SNOW ACCUMS.
ON MONDAY...EXPANSIVE HIGH PRESSURE STRETCHING FROM THE GREAT LAKES
TO THE GULF WILL SLIDE EAST ACROSS THE REGION. WHILE THE LOWERING
SUBSIDENCE INVERSION WILL FURTHER CHOKE OFF ANY LAKE EFFECT...H85
TEMPS AVG -12C AND A WEAK NORTHERLY UPSLOPE FLOW WILL PROBABLY KEEP
A FAIR AMOUNT OF CLOUDS AROUND AND POSSIBLY SOME VERY LIGHT SNOW
SHOWERS. THIS WILL MAINLY BE THE CASE FOR SITES SOUTH OF LK
ONTARIO...WITH THE NORTH COUNTRY LIKELY HAVING THE BEST CHANCES OF
EXPERIENCING ANY SUNSHINE.
THE LARGE SFC HIGH WILL DRIFT EAST ON TUESDAY AND WEDNESDAY WHILE A
PROGRESSIVE RIDGE WILL BUILD ACROSS THE REGION. THIS WILL LEAD TO
TWO SUNNY DAYS ACROSS OUR REGION WITH A NOTICEABLE DAY TO DAY
WARMING TREND AS H85 TEMPS JUMP TO BETWEEN +4 AND +8C.
&&
.AVIATION /04Z THURSDAY THROUGH MONDAY/...
LOW PRESSURE AND AN ASSOCIATED UPPER LEVEL DISTURBANCE WILL SLOWLY TRACK
FROM MICHIGAN TO EASTERN GREAT LAKES REGION OVERNIGHT. A SHARP
INVERSION WILL SET UP OUT AHEAD OF THIS LOW...WITH THIS FORECAST
TO LOWER THIS EVENING. EXPECT MAINLY IFR OR LOWER CONDITIONS AT
JHW/BUF/IAG/ROC IN THIS ENVIRONMENT...WITH A PERIOD OF 1/2SM OR
LOWER VSBY POSSIBLE. FOR NOW...SHOW LOWERING TREND IN TAFS...BUT
ONLY BRING JHW BELOW 1/2SM IN FOG. VSBY/CIGS SHOULD IMPROVE SOME AS
SHOWERS ASSOCIATED WITH THE UPPER TROF MOVE THROUGH LATE THIS
EVENING AND OVERNIGHT. AN ISOLATED STRIKE OF LIGHTNING IS POSSIBLE
AS THESE SHOWERS MOVE THROUGH IN ELEVATED INSTABILITY.
ITS A DIFFERENT STORY AT ART...WHERE LIGHT SNOW TRANSITIONING TO
MIXED PRECIPITATION WILL BE THE MAIN IMPACT. EXPECT LOWEST VSBY IN
SNOW EARLY THIS EVENING. THEN VSBY SHOULD IMPROVE AS PRECIPITATION
TAPERS AND MIXES...BUT CIGS MAY LOWER AS MOISTURE INCREASES.
EXPECT A MARGINAL IMPROVEMENT FOR THURSDAY...WITH MAINLY MVFR
CONDITIONS IN SCATTERED RAIN AND SNOW SHOWERS...AND IN CIGS.
OUTLOOK...
THURSDAY...IFR TO MVFR WITH RAIN AND SNOW SHOWERS TAPERING OFF FROM
WEST TO EAST.
FRIDAY...GENERALLY VFR.
SATURDAY...MVFR WITH RAIN SHOWERS LIKELY.
SUNDAY AND MONDAY...VFR/MVFR WITH SCATTERED SNOW SHOWERS.
&&
.MARINE...
BASED ON THE 00Z NAM/RUC FORECASTS...AND CONSIDERING THE TRACK OF
THE SURFACE LOW...OPTED TO ISSUE A SMALL CRAFT ADVISORY FOR LAKE
ERIE. EXPECT A 3 TO 6 HOUR PERIOD OF 20 TO 25 KNOT WINDS IN A
SOUTHWEST FLOW THURSDAY MORNING.
EAST TO SOUTHEAST WINDS ALONG THE WESTERN SHORES OF LAKE ONTARIO
WILL PRODUCE SMALL CRAFT ADVISORY CONDITIONS FOR THE OVERNIGHT HOURS
AS A WARM FRONT REMAINS DRAPED ACROSS THE LAKE ONTARIO BASIN. ONCE
THE LOW PRESSURE CENTER PASSES BY LATE TONIGHT/EARLY THURSDAY
MORNING...WINDS WILL QUICKLY VEER TO SOUTHWEST AND PICK UP
AGAIN...PARTICULARLY ON LAKE ERIE WHERE ADDITIONAL SMALL CRAFT
ADVISORIES SHOULD EVENTUALLY BECOME NECESSARY.
&&
.CLIMATE...
A REMARKABLE MILD WINTER CONTINUED INTO FEBRUARY WITH MONTHLY
TEMPERATURES AVERAGING OVER 5 DEGREES ABOVE NORMAL FOR A 4TH
CONSECUTIVE MONTH. VERY FEW RECORD HIGHS WERE SET IN THIS 4 MONTH
STRETCH...RATHER JUST A PERSISTENT MILD PATTERN THROUGH THE WINTER.
FOR THE DECEMBER-JANUARY-FEBRUARY TIME FRAME THE LONGEST STRETCH OF
SUB FREEZING TEMPERATURES WAS ONLY 4 DAYS FOR BOTH BUFFALO AND
ROCHESTER (JAN 18-21). NO OTHER STRETCH WAS LONGER THAN 2
DAYS...IMPRESSIVE CONSIDERING BUFFALO AND ROCHESTER AVERAGES 39
DAYS BELOW FREEZING IN THE DECEMBER THROUGH FEBRUARY TIMEFRAME.
FOR FEBRUARY BUFFALO HAD 25 DAYS REACHING OR EXCEEDING THE FREEZING
MARK...TIED WITH 1998 FOR GREATEST NUMBER OF DAYS IN THE MONTH OF
FEBRUARY REACHING OR EXCEEDING 32F. ROCHESTER HAD 25 SUCH DAYS AS
WELL...THE GREATEST EVER IN THE MONTH OF FEBRUARY.
WHILE BUFFALO HAD MINIMAL SNOW IN FEBRUARY WITH JUST 9.6 INCHES
FALLING...ROCHESTER DID FAIR BETTER UNDER SEVERAL LAKE EFFECT SNOW
BANDS WHICH HELPED BRING 26.8 INCHES OF SNOW TO THE ROCHESTER
AIRPORT FOR FEBRUARY. IN BUFFALO THE DJF SNOWFALL OF 34.2 INCHES IS
THE 4TH LOWEST SINCE THE MOVE TO THE AIRPORT...WITH 25.8 INCHES IN
THE WINTER OF 1947-48 HAVING THE LEAST TOTAL (25.8 INCHES).
DAYS WITH SNOW COVER WAS LACKING ACROSS THE REGION THIS WINTER.
BUFFALO HAD ONLY 22 DAYS IN DJF WITH AN INCH OR MORE OF SNOW ON THE
GROUND. THIS IS TIED FOR 4TH LOWEST IN 119 YEARS OF RECORD
KEEPING...AND 2ND LOWEST SINCE RECORD KEEPING MOVED TO THE AIRPORT.
THE LOWEST DJF DAYS WITH ONE INCH OR MORE OF SNOW ON THE GROUND ARE:
1931-32 (16) 1948-49 (18) AND 1936-37 (20). ROCHESTER ALSO HAD A
LACK OF DAYS WITH SNOW COVERING THE GROUND...ONLY 25 DAYS HAVING AT
LEAST AN INCH OF SNOW ON THE GROUND. IN 86 YEARS OF ROCHESTER RECORD
ONLY THE SEASON 1932-33 HAD A LOWER TOTAL...WITH 21 DAYS.
FOR THE ENTIRE WINTER SEASON (JULY-JUNE)...BUFFALO CAN FINISH NO
HIGHER THAN 3RD PLACE ALL-TIME FOR LACK OF SNOW...AND ROCHESTER
WHICH HAS FAIRED BETTER THIS WINTER CAN FINISH NO HIGHER THAN 10TH
PLACE. BELOW IS A TABLE FOR BUFFALO FOR LEAST SNOWIEST WINTERS.
RANK SEASON WINTER SNOWFALL
(INCHES)
1 1889-90 22.4
2 1918-19 25.0
3 1921-22 39.8
4 1948-49 40.1
5 1947-48 42.1
TO DATE SNOWFALL IN BUFFALO STANDS AT 34.2 INCHES.
FOR ROCHESTER WE WILL TAKE A LOOK AT YEARS SINCE 1950 SINCE WE ARE
LIKELY OUT OF THE RUNNING FOR A TOP TEN ALL-TIME LEAST AMOUNT OF SNOW.
RANK SEASON WINTER SNOWFALL (SINCE 1950)
(INCHES)
1 1952-53 41.7
2 1994-95 56.2
3 2001-02 58.1
4 1982-83 59.9
5 1961-62 65.6
TO DATE SNOWFALL IN ROCHESTER STANDS AT 52.0 INCHES.
&&
.BUF WATCHES/WARNINGS/ADVISORIES...
NY...WINTER WEATHER ADVISORY UNTIL 4 PM EST THURSDAY FOR NYZ006>008.
MARINE...SMALL CRAFT ADVISORY FROM 6 AM TO 5 PM EST THURSDAY FOR LEZ040-
041.
SMALL CRAFT ADVISORY UNTIL 4 AM EST THURSDAY FOR
LOZ042.
&&
$$
SYNOPSIS...WCH
NEAR TERM...APFFEL/WCH
SHORT TERM...RSH
LONG TERM...RSH
AVIATION...APFFEL
MARINE...APFFEL/WCH
CLIMATE...THOMAS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
410 AM EST THU MAR 01 2012
.SYNOPSIS...
A WEAK FRONT WILL PROGRESS INTO THE AREA TODAY AND STALL NEAR THE
SOUTH CAROLINA BORDER TONIGHT. THE STALLED BOUNDARY WILL LIFT
RAPIDLY NORTHWARD AS A WARM FRONT ON FRIDAY...AS A DEEPENING LOW
PRESSURE SYSTEM TRACKS NORTHEAST INTO THE OHIO VALLEY AND A POTENT
COLD FRONT APPROACHES THE MOUNTAINS FROM THE WEST.
&&
.NEAR TERM /TODAY AND TONIGHT/...
AS OF 315 AM THURSDAY...
OVERVIEW:
AN UPPER LOW CENTERED OVER MICHIGAN AT 06Z WILL DEAMPLIFY AS IT
SLOWLY TRACKS EAST TO THE LOWER GREAT LAKES BY 12Z...AND INTO NEW
ENGLAND BY 00Z THIS EVENING. A 125-KT H3 JET EXTENDING FROM WESTERN
TX INTO THE TN VALLEY AT 06Z IS PROGGED TO NOSE EAST INTO THE
CAROLINAS BY LATE MORNING/EARLY AFTERNOON...WITH CYCLONIC SHEAR
VORTICITY ON THE NORTHERN PERIPHERY OF THE JET INCREASING OVER
SOUTHERN VA AND CENTRAL NC BETWEEN 06-18Z. IN THE LOWER LEVELS...A
COLD FRONT (MORE-SO A DEWPOINT DISCONTINUITY AT THIS LATITUDE)
EXTENDED NORTHEAST FROM CENTRAL TN INTO EASTERN KY/SOUTHWEST VA AT
06Z...AND IS PROGGED TO PROGRESS INTO CENTRAL NC THIS AFTERNOON...
BECOMING INCREASINGLY WEST-EAST ORIENTED AND EVENTUALLY STALLING
NEAR THE NC/SC BORDER BY 00Z THIS EVENING. THE FRONT IS EXPECTED TO
REMAIN STALLED NEAR THE NC/SC BORDER THROUGH 12Z FRI.
CONVECTION:
07Z REGIONAL RADAR SHOWED A BROKEN LINE OF WEAKENING CONVECTION
EXTENDING FROM THE SOUTHWEST TN/NC BORDER INTO THE NORTHWEST
PIEDMONT. UPPER LEVEL FORCING IN THE FORM OF CYCLONIC SHEAR
VORTICITY (ON THE NORTHERN PERIPHERY OF THE 125-KT H3 JET BEGINNING
TO NOSE INTO THE CAROLINAS) WILL STRENGTHEN THROUGH 15Z THIS
MORNING. DESPITE THE APPROACHING FRONT...LOW-LEVEL FLOW REMAINS
LARGELY UNIDIRECTIONAL...AND ANY CONVERGENCE WILL BE WEAK/SHALLOW AS
THE FRONT SLOWLY PROGRESSES INTO CENTRAL NC BETWEEN 12-21Z.
INSTABILITY THIS MORNING IS MARGINAL...WITH THE LATEST SPC
MESOANALYSIS INDICATING NO MORE THAN 250 J/KG OF MLCAPE AT 07Z.
ADDITIONALLY...A LOW-LEVEL (800-900 MB) INVERSION IN PLACE ACROSS
CENTRAL NC THIS MORNING (ASSOC/W SUBSIDENCE IN THE WAKE OF A COLD
FRONT ALOFT - DIAGNOSED VIA RUC H7 THETA-E) IS SERVING RATHER
EFFECTIVELY AS A CAP...ESPECIALLY GIVEN THE LACK OF A LOW-LEVEL
FOCUS. WITH THE ABOVE IN MIND...EXPECT THE CURRENT BROKEN LINE OF
SHOWERS/ISOLD STORMS IN ADVANCE OF THE FRONT TO CONTINUE WEAKENING
THROUGH SUNRISE...WITH THE BEST CHANCE OF SHOWER ACTIVITY NEAR THE
NC/VA BORDER. *IF* UPPER LEVEL FORCING IS SUFFICIENT TO ERODE THE
CAP AND INITIATE STRONG UPDRAFTS IN THE PRESENCE OF MEAGER
INSTABILITY PRIOR TO ~15Z...SUFFICIENT LOW/DEEP LAYER SHEAR IS
PRESENT FOR SUPERCELLULAR ORGANIZATION AND AN ATTENDANT THREAT FOR
DAMAGING WINDS OR AN ISOLD TORNADO.
DESPITE THE SURFACE FRONT MAKING SLOW PROGRESS THROUGH SOUTHERN/
EASTERN PORTIONS OF THE AREA THIS AFTERNOON AND THE POSSIBLE
PRESENCE OF MARGINAL SFC-BASED INSTABILITY SOUTH OF HWY 64 WHERE
DEWPOINTS WILL TAKE LONGER TO FALL IN THE PRESENCE OF STRONG DIURNAL
HEATING...PRONOUNCED DRYING IS EXPECTED THROUGHOUT THE MID/UPPER
LEVELS TODAY AS A DRIER AIRMASS ADVECTS INTO NC VIA SPEEDY WESTERLY
FLOW ALOFT...AND WITHOUT SIGNIFICANT UPPER LEVEL FORCING/
LAYER-LIFTING...IT SHOULD BE DIFFICULT FOR ANYTHING ASIDE FROM
DIURNAL CU OR TURKEY TOWERS TO DEVELOP AFTER 12-15Z. WILL INDICATE A
DRY FORECAST AFTER SUNRISE. EXPECT DRY CONDITIONS TO PERSIST
OVERNIGHT AS THE SURFACE FRONT STALLS NEAR THE NC/SC BORDER AND A
VERY DRY MID/UPPER LEVEL AIRMASS REMAINS IN PLACE.
TEMPERATURES:
1000-850 MB THICKNESSES TODAY ARE PROGGED TO BE VERY SIMILAR TO
YESTERDAY...IN THE 1370-1390 METER RANGE. THESE THICKNESSES COMBINED
WITH MORNING LOWS IN THE LOWER/MID 60S AND PRONOUNCED DRYING
THROUGHOUT THE COLUMN (SUNNY SKIES) SUGGEST HIGHS WELL ABOVE NORMAL.
IN FACT...HIGHS TODAY COULD WELL REACH 20-25F ABOVE NORMAL READINGS
THIS TIME OF YEAR (MID/UPPER 50S). MOS GUIDANCE IS INDICATING HIGHS
~80F AT RDU...80-82F AT FAY...AND 77-78F AT GSO...ALL OF WHICH SEEM
PRETTY REASONABLE BASED ON THE ABOVE FACTORS. WILL INDICATE HIGHS
RANGING FROM THE MID/UPPER 70S TO LOWER 80S...WARMEST SOUTH OF HWY
64. WEAK COLD ADVECTION IS EXPECTED TONIGHT AS HIGH PRESSURE
PROGRESSES FROM THE OH VALLEY TO THE DELMARVA IN THE WAKE OF THE
AFOREMENTIONED COLD FRONT EXPECTED TO STALL OUT NEAR THE NC/SC
BORDER LATER THIS EVENING. LOWS WILL HIGHLY DEPEND ON EXACTLY WHERE
THE FRONT STALLS OUT...AND THE TEMPERATURE FCST IS MOST UNCERTAIN
SOUTH OF HWY 64 TONIGHT. EXPECT LOWS RANGING FROM THE LOWER/MID 40S
NORTH OF HWY 64 TO MID/UPPER 40S AND LOWER 50S SOUTH OF HWY 64...
WARMEST NEAR THE SC BORDER. -VINCENT
&&
.SHORT TERM /FRIDAY/...
AS OF 345 AM THURSDAY...
SHORTWAVE ENERGY CURRENTLY DIGGING INTO THE PACIFIC NW WILL PROGRESS
SOUTHEAST INTO THE CENTRAL ROCKIES TONIGHT THEN EAST INTO THE
CENTRAL PLAINS ON FRIDAY. ADDITIONAL SHORTWAVE ENERGY WILL TRACK
EAST THROUGH THE UPPER MIDWEST INTO THE UPPER GREAT LAKES TONIGHT/
FRIDAY. DPVA/HEIGHT FALLS IN THE LEE OF THE ROCKIES WILL RESULT IN
CYCLOGENESIS OVER THE CENTRAL PLAINS TONIGHT...WITH THE SURFACE LOW
DEEPENING AND TRACKING NORTHEAST INTO THE OH VALLEY BY 00Z SAT AS
ADDITIONAL SHORTWAVE ENERGY ROUNDS THE BASE OF THE UPPER TROUGH OVER
THE CENTRAL CONUS AND AMPLIFIES AS IT PROGRESSES NORTHEAST INTO THE
CENTRAL/NORTHERN MS RIVER VALLEY. WITH A DEEPENING SFC LOW WEST OF
THE APPALACHIANS...EXPECT STRENGTHENING LOW-LEVEL SOUTHERLY FLOW ON
FRIDAY...AND THE STALLED FRONT NEAR THE NC/SC BORDER IS EXPECTED TO
RAPIDLY LIFT NORTHWARD THROUGH CENTRAL NC INTO THE MID-ATLANTIC AS A
WARM FRONT DURING THE AFTERNOON. EXPECT A SHORT PERIOD OF STRONG
WARM ADVECTION/ISENTROPIC LIFT MID FRIDAY MORNING THROUGH EARLY/MID
FRIDAY AFTERNOON. EXPECT THE BEST CHANCE FOR RAIN/SHOWERS IN CENTRAL
NC TO OCCUR IN THAT TIME FRAME...WITH A LULL IN ACTIVITY LIKELY BY
MID/LATE AFTERNOON AS THE STRONGEST ISENTROPIC LIFT SHIFTS NORTH
INTO THE MID-ATLANTIC IN ADVANCE OF THE SURFACE WARM FRONT AND
LITTLE OR NOTHING IN THE WAY OF ADDITIONAL LOWER OR UPPER LEVEL
FORCING OVER THE AREA THROUGH 00Z SAT EVENING (UNIDIRECTIONAL
LOW-LEVEL FLOW AND NEUTRAL HEIGHTS ALOFT). THE LATEST 00Z GUIDANCE
SHOWS PRECIP AMOUNTS RANGING FROM A FEW HUNDREDTHS TO
~0.15"...HIGHEST NEAR THE VA BORDER. THIS MAKES SENSE...GIVEN THAT
NORTHERN PORTIONS OF THE AREA WILL SEE THE RELATIVE LONGEST PERIOD
OF ISENTROPIC LIFT AS THE SURFACE WARM FRONT TRACKS NORTHWARD FROM
THE NC/SC BORDER. WILL INDICATE THE BEST PRECIP CHANCES IN THE NORTH
AND THE LOWEST IN THE SOUTH. DESPITE CLOUD COVER AND RAIN OVER THE
AREA FOR AT LEAST PART OF THE DAY (ESP NORTH/NW PIEDMONT)...STRONG
WARM ADVECTION AND STRENGTHENING SOUTHERLY FLOW SHOULD RESULT IN
WELL-ABOVE NORMAL HIGHS AGAIN...ESPECIALLY WITH THE SOME BREAKS IN
CLOUD COVER POSSIBLE DURING MID/LATE AFTERNOON AS THE BEST
ISENTROPIC LIFT SHIFTS WELL NORTH OF THE AREA. MOS GUIDANCE IS
INDICATING HIGHS RANGING FROM 70-78F...COOLEST NORTH/WARMEST
SOUTH...AND THIS LOOKS PRETTY REASONABLE BASED ON THE ABOVE
REASONING.
SEVERE THREAT:
A CONDITIONAL THREAT OF SEVERE WEATHER WILL BE PRESENT LATE FRIDAY
AFTERNOON INTO FRIDAY EVENING AS A WARM/MOIST AIRMASS WITH AT LEAST
SOME SFC-BASED INSTABILITY BECOMES ESTABLISHED IN THE WAKE OF THE
WARM FRONTAL PASSAGE EARLIER IN THE AFTERNOON. ALTHOUGH LITTLE OR NO
LOWER/UPPER LEVEL FORCING IS EXPECTED TO BE PRESENT THROUGH ~00Z
SATURDAY (AS MENTIONED ABOVE)...THERE ARE AT LEAST TWO SCENARIOS
WHERE SEVERE WEATHER COULD DEVELOP. 1) A SHORTWAVE DISTURBANCE IN
WSW/SW FLOW ALOFT TRACKS OVER THE AREA DURING THE MID/LATE AFTERNOON
AFTER AIRMASS DESTABILIZATION HAS OCCURRED (POSSIBLE BUT VERY
DIFFICULT TO ANTICIPATE AT THIS RANGE)...OR 2) AN MCS OR ORGANIZED
CONVECTION DEVELOPS UPSTREAM OF THE AREA AND MOVES DOWNSTREAM OF THE
ORIGINAL FORCING MECHANISMS INTO CENTRAL NC IN THE PRESENCE OF A
MOIST/MARGINALLY UNSTABLE AIRMASS THAT CAN MAINTAIN THE
AFOREMENTIONED CONVECTION...PARTICULARLY IN THE PRESENCE OF STRONG
LOW/DEEP LAYER SHEAR SUPPORTIVE OF SUPERCELLS. -VINCENT
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
AS OF 250 AM THURSDAY...
SHOWERS AND THUNDERSTORMS (SOME POTENTIALLY SEVERE) ARE EXPECTED TO
INCREASE AS A COLD FRONT APPROACHES FRIDAY NIGHT... AND SLOWLY
SHIFTS EAST THROUGH THE AREA SATURDAY.
WIDELY SCATTERED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE
ANTICIPATED TO BE ONGOING TO START FRIDAY EVENING. THERE MAY ALSO BE
A SLIGHT SEVERE RISK THAT EITHER WILL EXTEND INTO THE EVENING FROM
THE AFTERNOON... OR POTENTIALLY ARRIVE FROM THE WEST DURING THE
EVENING OR OVERNIGHT. MUCH WILL DEPEND ON THE TIMING AND POSITION OF
THE WARM FRONT THROUGH OUR REGION FRIDAY AFTERNOON/EVENING... AND
THE APPROACH OF THE NEXT COLD FRONT LATE FRIDAY NIGHT INTO SATURDAY.
WE WILL CARRY CHANCE POP FRIDAY EVENING AND NIGHT WITH THE HIGHEST
PROBS EXPECTED WEST AND NORTH (CLOSER TO THE RETREATING WARM FRONT
AND THE APPROACHING COLD FRONT). LOWS WILL BE WARM (WITH DEW POINTS
IN THE 50S TO LOWER 60S AND A SIGNIFICANT LOW LEVEL SSW JET). EXPECT
PROBABLY NO LOWER THAN 60 FOR LOWS.
SATURDAY...THE LATEST GUIDANCE IS A BIT MORE PROGRESSIVE WITH THE
LEAD COLD FRONT SATURDAY AS IT IS FORECAST TO PUSH EAST ACROSS NC.
WE WILL CONTINUE TO LEAN TOWARD THE PREFERRED OPERATIONAL EUROPEAN
MODEL IN PLACEMENT OF THE MAIN FRONT. THIS SUGGESTS THAT THE COLD
FRONT SHOULD BE ALONG THE APPALACHIANS AT 12Z/SAT WITH A BAND OF
SHOWERS AND THUNDERSTORMS EITHER OUT AHEAD OF THE FRONT (PRE-FRONTAL
TROUGH) OR ALONG THE FRONT ITSELF INTO OUR PIEDMONT BY THAT TIME.
THE FRONT AND PRE-FRONTAL TROUGH/BAND OF CONVECTION THEN TAKES MUCH
OF THE DAY TO PUSH THROUGH OUR REGION... REACHING THE COAST AROUND
00Z/SUN. THE FRONT THEN STALLS WITH LINGERING UPPER SUPPORT HANGING
BACK OVER THE APPALACHIANS SAT NIGHT... WITH ANOTHER SURFACE WAVE
DEVELOPMENT OVER THE COASTAL PLAIN OF GA/SC SAT NIGHT... SHIFTING
EAST AND OFFSHORE SUNDAY. THIS WOULD SUGGEST KEEPING RAIN IN THE
FORECAST MAINLY ACROSS THE EAST AND SOUTH SATURDAY NIGHT INTO SUNDAY
AFTERNOON. THE LATEST GFS/NAM CONTINUE TO SHOW LESS IN THE WAY OF
WAVE DEVELOPMENT. WE WILL LEAN TOWARD THE WETTER EC GIVEN ITS
STRONGER PERFORMANCE RECENTLY.
BOTTOM LINE...A THREAT (PROBABLY A SLIGHT RISK) OF SEVERE
THUNDERSTORMS FRIDAY NIGHT INTO SATURDAY. A BAND OF SHOWERS AND
STORMS SHOULD AFFECT THE ENTIRE REGION FOR 3-6 HOURS TIME STARTING
IN THE WEST BEFORE DAYBREAK SATURDAY... THEN TRACKING SLOWLY EAST
ACROSS CENTRAL NC SATURDAY. QPF OF A HALF INCH TO ONE INCH WILL BE
LIKELY WITH LOCALLY HIGHER TOTALS. TURNING COOLER SATURDAY NIGHT AND
SUNDAY WITH RAIN LIKELY EAST... AND A CHANCE OF RAIN WEST.
ADDITIONAL SIGNIFICANT QPF POSSIBLE MAINLY EAST AND SOUTH. HIGHS
SATURDAY 65-75 NW TO SE. LOWS SATURDAY NIGHT 40S WEST/LOWER 50S SE.
HIGHS HOLDING IN THE 50S SUNDAY.
MONDAY THROUGH WEDNESDAY...
IT APPEARS THAT WE ARE SET TO REVERT BACK TO A DEEPENING MID-UPPER
TROUGH OVER THE WEST-CENTRAL STATES... WITH RISING HEIGHTS ACROSS
THE SE STATES TUE-WED. BEFORE THAT OCCURS... IT APPEARS THAT MONDAY
WILL BE A CHILLY AND VARIABLY CLOUDY DAY AS THE CORE OF THE
MID-UPPER TROUGH IS EXPECTED TO BE OVER THE MID-ATLANTIC STATES.
MODELS ARE INDICATING THE POSSIBILITY OF A FINAL BUT STRONG
VORTICITY MAXIMUM TO ROTATE SE ACROSS NC OR VA MONDAY. DEPENDING ON
THE EVENTUAL TRACK AND STRENGTH OF THIS VORT MAX... WE COULD SEE A
CHANCE OF SHOWERS AGAIN MONDAY. PARTIALS SUGGEST RAIN SHOWERS AND
THE THERMAL PROFILES INDICATE TEMPS SHOULD BE 40+ EVEN IF THE TRACK
IS SOUTH (COLDER FOR US). THEREFORE... ONLY A SMALL CHANCE OF RAIN
SHOWERS WILL BE FORECAST MONDAY.
TUESDAY AND WEDNESDAY APPEAR TO BE IN LINE FOR SUN AND INCREASING
TEMPS AGAIN AFTER A NIGHT OR TWO AT OR BELOW 32.
&&
.AVIATION /06Z THURSDAY THROUGH SUNDAY/...
AS OF 110 AM THURSDAY...
AFTER MAINLY VFR CONDITIONS AS OF 06Z...MOIST LOW LEVEL
SOUTHWESTERLY FLOW WILL PRODUCE A MEDIUM TO HIGH CHANCE OF IFR
CEILINGS BETWEEN 08-14Z THIS MORNING...LIKELY TO LAST LONGEST AT
KRWI AND KFAY. OTHERWISE...THE IMMEDIATE THREAT OF CONVECTION HAS
DIMINISHED...AND THERE IS HIGH UNCERTAINTY REGARDING WHETHER OR NOT
THE PRE-FRONTAL CONVECTION ALONG THE SPINE OF THE BLUE RIDGE WILL
SURVIVE IN THE LEE OF THE MOUNTAINS AND AFFECT CENTRAL NC TERMINALS
BETWEEN 08-12Z. HAVE INCLUDED ONLY TEMPORARY SHOWERS AT TRIAD
TERMINALS TO ACCOUNT FOR THIS POSSIBILITY...BUT SUBSEQUENT
AMENDMENTS MAY BE NECESSARY IF OBSERVATIONAL DATA TRENDS SUGGEST THE
LINE WILL MAINTAIN ITSELF ALL THE WAY THROUGH CENTRAL NC.
OTHERWISE...A BREEZY SOUTHWEST WIND WILL CONTINUE THIS MORNING...IN
STRONG LOW LEVEL FLOW AHEAD OF THE PARENT COLD FRONT THAT WILL
SETTLE SLOWLY THROUGH CENTRAL NC IN DRY FASHION LATER TODAY AND
TONIGHT. CLEARING SKIES WILL ENSUE WITH DAYTIME HEATING AND MIXING
BY 13-15Z...AT WHICH TIME SURFACE WINDS WILL ALSO VEER TO A MORE
WESTERLY COMPONENT...WITH GUSTS INTO THE 20-25 KT RANGE...LATE
MORNING THROUGH SUNSET. ANOTHER STORM SYSTEM WILL RESULT IN A HIGH
PROBABILITY OF SUB-VFR STRATUS AND CONVECTION LATE FRIDAY THROUGH
SATURDAY.
&&
.FIRE WEATHER...
AS OF 315 AM WEDNESDAY...
LITTLE TO NO RAINFALL OCCURRED OVER CENTRAL NC YESTERDAY EVENING
THROUGH THIS MORNING. A DRY FRONT WILL SLOWLY PROGRESS INTO THE AREA
THIS AFTERNOON...EVENTUALLY STALLING NEAR THE SC BORDER TONIGHT. A
DRIER AIRMASS WILL ADVECT INTO THE AREA IN THE WAKE OF THE FRONT
THIS AFTERNOON. RELATIVE HUMIDITY VALUES WILL LIKELY FALL TO 30% OR
LOWER NORTH OF HWY 64. SOUTH OF HWY 64...MINIMUM RH`S THIS AFTERNOON
WILL HIGHLY DEPEND ON THE PROGRESS OF THE FRONT (AND THE DRIER
AIRMASS ADVECTING INTO THE AREA)...AND COULD RANGE ANYWHERE FROM
25-45%...HIGHEST NEAR THE SC BORDER. BREEZY WESTERLY WINDS ARE
EXPECTED TODAY...SUSTAINED AT ~15 MPH WITH GUSTS UP TO 25-30 MPH.
THE COMBINATION OF LOW RH`S...LITTLE OR NO RECENT RAINFALL...AND
BREEZY WESTERLY WINDS WILL RESULT IN AN INCREASED FIRE DANGER THIS
AFTERNOON...ESPECIALLY NORTH OF HWY 64 (IN THE NORTHERN AND NW
PIEDMONT). WILL ISSUE AN INCREASED FIRE DANGER SPS FOR THE NORTHERN
2/3 OF CENTRAL NC...OMITTING THE FAR SOUTHERN TIER OF COUNTIES WHERE
RH`S ARE MORE LIKELY TO REMAIN IN THE 35-45% RANGE. -VINCENT
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...VINCENT
SHORT TERM...VINCENT
LONG TERM...BADGETT
AVIATION...MWS
FIRE WEATHER...VINCENT
AREA FORECAST DISCUSSION
NWS RALEIGH NC
327 AM EST THU MAR 01 2012
.SYNOPSIS...
A WEAK FRONT WILL PROGRESS INTO THE AREA TODAY AND STALL NEAR THE
SOUTH CAROLINA BORDER TONIGHT. THE STALLED BOUNDARY WILL LIFT
RAPIDLY NORTHWARD AS A WARM FRONT ON FRIDAY...AS A DEEPENING LOW
PRESSURE SYSTEM TRACKS NORTHEAST INTO THE OHIO VALLEY AND A POTENT
COLD FRONT APPROACHES THE MOUNTAINS FROM THE WEST.
&&
.NEAR TERM /TODAY AND TONIGHT/...
AS OF 315 AM THURSDAY...
OVERVIEW:
AN UPPER LOW CENTERED OVER MICHIGAN AT 06Z WILL DEAMPLIFY AS IT
SLOWLY TRACKS EAST TO THE LOWER GREAT LAKES BY 12Z...AND INTO NEW
ENGLAND BY 00Z THIS EVENING. A 125-KT H3 JET EXTENDING FROM WESTERN
TX INTO THE TN VALLEY AT 06Z IS PROGGED TO NOSE EAST INTO THE
CAROLINAS BY LATE MORNING/EARLY AFTERNOON...WITH CYCLONIC SHEAR
VORTICITY ON THE NORTHERN PERIPHERY OF THE JET INCREASING OVER
SOUTHERN VA AND CENTRAL NC BETWEEN 06-18Z. IN THE LOWER LEVELS...A
COLD FRONT (MORE-SO A DEWPOINT DISCONTINUITY AT THIS LATITUDE)
EXTENDED NORTHEAST FROM CENTRAL TN INTO EASTERN KY/SOUTHWEST VA AT
06Z...AND IS PROGGED TO PROGRESS INTO CENTRAL NC THIS AFTERNOON...
BECOMING INCREASINGLY WEST-EAST ORIENTED AND EVENTUALLY STALLING
NEAR THE NC/SC BORDER BY 00Z THIS EVENING. THE FRONT IS EXPECTED TO
REMAIN STALLED NEAR THE NC/SC BORDER THROUGH 12Z FRI.
CONVECTION:
07Z REGIONAL RADAR SHOWED A BROKEN LINE OF WEAKENING CONVECTION
EXTENDING FROM THE SOUTHWEST TN/NC BORDER INTO THE NORTHWEST
PIEDMONT. UPPER LEVEL FORCING IN THE FORM OF CYCLONIC SHEAR
VORTICITY (ON THE NORTHERN PERIPHERY OF THE 125-KT H3 JET BEGINNING
TO NOSE INTO THE CAROLINAS) WILL STRENGTHEN THROUGH 15Z THIS
MORNING. DESPITE THE APPROACHING FRONT...LOW-LEVEL FLOW REMAINS
LARGELY UNIDIRECTIONAL...AND ANY CONVERGENCE WILL BE WEAK/SHALLOW AS
THE FRONT SLOWLY PROGRESSES INTO CENTRAL NC BETWEEN 12-21Z.
INSTABILITY THIS MORNING IS MARGINAL...WITH THE LATEST SPC
MESOANALYSIS INDICATING NO MORE THAN 250 J/KG OF MLCAPE AT 07Z.
ADDITIONALLY...A LOW-LEVEL (800-900 MB) INVERSION IN PLACE ACROSS
CENTRAL NC THIS MORNING (ASSOC/W SUBSIDENCE IN THE WAKE OF A COLD
FRONT ALOFT - DIAGNOSED VIA RUC H7 THETA-E) IS SERVING RATHER
EFFECTIVELY AS A CAP...ESPECIALLY GIVEN THE LACK OF A LOW-LEVEL
FOCUS. WITH THE ABOVE IN MIND...EXPECT THE CURRENT BROKEN LINE OF
SHOWERS/ISOLD STORMS IN ADVANCE OF THE FRONT TO CONTINUE WEAKENING
THROUGH SUNRISE...WITH THE BEST CHANCE OF SHOWER ACTIVITY NEAR THE
NC/VA BORDER. *IF* UPPER LEVEL FORCING IS SUFFICIENT TO ERODE THE
CAP AND INITIATE STRONG UPDRAFTS IN THE PRESENCE OF MEAGER
INSTABILITY PRIOR TO ~15Z...SUFFICIENT LOW/DEEP LAYER SHEAR IS
PRESENT FOR SUPERCELLULAR ORGANIZATION AND AN ATTENDANT THREAT FOR
DAMAGING WINDS OR AN ISOLD TORNADO.
DESPITE THE SURFACE FRONT MAKING SLOW PROGRESS THROUGH SOUTHERN/
EASTERN PORTIONS OF THE AREA THIS AFTERNOON AND THE POSSIBLE
PRESENCE OF MARGINAL SFC-BASED INSTABILITY SOUTH OF HWY 64 WHERE
DEWPOINTS WILL TAKE LONGER TO FALL IN THE PRESENCE OF STRONG DIURNAL
HEATING...PRONOUNCED DRYING IS EXPECTED THROUGHOUT THE MID/UPPER
LEVELS TODAY AS A DRIER AIRMASS ADVECTS INTO NC VIA SPEEDY WESTERLY
FLOW ALOFT...AND WITHOUT SIGNIFICANT UPPER LEVEL FORCING/
LAYER-LIFTING...IT SHOULD BE DIFFICULT FOR ANYTHING ASIDE FROM
DIURNAL CU OR TURKEY TOWERS TO DEVELOP AFTER 12-15Z. WILL INDICATE A
DRY FORECAST AFTER SUNRISE. EXPECT DRY CONDITIONS TO PERSIST
OVERNIGHT AS THE SURFACE FRONT STALLS NEAR THE NC/SC BORDER AND A
VERY DRY MID/UPPER LEVEL AIRMASS REMAINS IN PLACE.
TEMPERATURES:
1000-850 MB THICKNESSES TODAY ARE PROGGED TO BE VERY SIMILAR TO
YESTERDAY...IN THE 1370-1390 METER RANGE. THESE THICKNESSES COMBINED
WITH MORNING LOWS IN THE LOWER/MID 60S AND PRONOUNCED DRYING
THROUGHOUT THE COLUMN (SUNNY SKIES) SUGGEST HIGHS WELL ABOVE NORMAL.
IN FACT...HIGHS TODAY COULD WELL REACH 20-25F ABOVE NORMAL READINGS
THIS TIME OF YEAR (MID/UPPER 50S). MOS GUIDANCE IS INDICATING HIGHS
~80F AT RDU...80-82F AT FAY...AND 77-78F AT GSO...ALL OF WHICH SEEM
PRETTY REASONABLE BASED ON THE ABOVE FACTORS. WILL INDICATE HIGHS
RANGING FROM THE MID/UPPER 70S TO LOWER 80S...WARMEST SOUTH OF HWY
64. WEAK COLD ADVECTION IS EXPECTED TONIGHT AS HIGH PRESSURE
PROGRESSES FROM THE OH VALLEY TO THE DELMARVA IN THE WAKE OF THE
AFOREMENTIONED COLD FRONT EXPECTED TO STALL OUT NEAR THE NC/SC
BORDER LATER THIS EVENING. LOWS WILL HIGHLY DEPEND ON EXACTLY WHERE
THE FRONT STALLS OUT...AND THE TEMPERATURE FCST IS MOST UNCERTAIN
SOUTH OF HWY 64 TONIGHT. EXPECT LOWS RANGING FROM THE LOWER/MID 40S
NORTH OF HWY 64 TO MID/UPPER 40S AND LOWER 50S SOUTH OF HWY 64...
WARMEST NEAR THE SC BORDER. -VINCENT
&&
.SHORT TERM /FRIDAY/...
AS OF 325 AM THURSDAY...
TO BE POSTED SHORTLY...
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
AS OF 250 AM THURSDAY...
SHOWERS AND THUNDERSTORMS (SOME POTENTIALLY SEVERE) ARE EXPECTED TO
INCREASE AS A COLD FRONT APPROACHES FRIDAY NIGHT... AND SLOWLY
SHIFTS EAST THROUGH THE AREA SATURDAY.
WIDELY SCATTERED TO SCATTERED SHOWERS AND THUNDERSTORMS ARE
ANTICIPATED TO BE ONGOING TO START FRIDAY EVENING. THERE MAY ALSO BE
A SLIGHT SEVERE RISK THAT EITHER WILL EXTEND INTO THE EVENING FROM
THE AFTERNOON... OR POTENTIALLY ARRIVE FROM THE WEST DURING THE
EVENING OR OVERNIGHT. MUCH WILL DEPEND ON THE TIMING AND POSITION OF
THE WARM FRONT THROUGH OUR REGION FRIDAY AFTERNOON/EVENING... AND
THE APPROACH OF THE NEXT COLD FRONT LATE FRIDAY NIGHT INTO SATURDAY.
WE WILL CARRY CHANCE POP FRIDAY EVENING AND NIGHT WITH THE HIGHEST
PROBS EXPECTED WEST AND NORTH (CLOSER TO THE RETREATING WARM FRONT
AND THE APPROACHING COLD FRONT). LOWS WILL BE WARM (WITH DEW POINTS
IN THE 50S TO LOWER 60S AND A SIGNIFICANT LOW LEVEL SSW JET). EXPECT
PROBABLY NO LOWER THAN 60 FOR LOWS.
SATURDAY...THE LATEST GUIDANCE IS A BIT MORE PROGRESSIVE WITH THE
LEAD COLD FRONT SATURDAY AS IT IS FORECAST TO PUSH EAST ACROSS NC.
WE WILL CONTINUE TO LEAN TOWARD THE PREFERRED OPERATIONAL EUROPEAN
MODEL IN PLACEMENT OF THE MAIN FRONT. THIS SUGGESTS THAT THE COLD
FRONT SHOULD BE ALONG THE APPALACHIANS AT 12Z/SAT WITH A BAND OF
SHOWERS AND THUNDERSTORMS EITHER OUT AHEAD OF THE FRONT (PRE-FRONTAL
TROUGH) OR ALONG THE FRONT ITSELF INTO OUR PIEDMONT BY THAT TIME.
THE FRONT AND PRE-FRONTAL TROUGH/BAND OF CONVECTION THEN TAKES MUCH
OF THE DAY TO PUSH THROUGH OUR REGION... REACHING THE COAST AROUND
00Z/SUN. THE FRONT THEN STALLS WITH LINGERING UPPER SUPPORT HANGING
BACK OVER THE APPALACHIANS SAT NIGHT... WITH ANOTHER SURFACE WAVE
DEVELOPMENT OVER THE COASTAL PLAIN OF GA/SC SAT NIGHT... SHIFTING
EAST AND OFFSHORE SUNDAY. THIS WOULD SUGGEST KEEPING RAIN IN THE
FORECAST MAINLY ACROSS THE EAST AND SOUTH SATURDAY NIGHT INTO SUNDAY
AFTERNOON. THE LATEST GFS/NAM CONTINUE TO SHOW LESS IN THE WAY OF
WAVE DEVELOPMENT. WE WILL LEAN TOWARD THE WETTER EC GIVEN ITS
STRONGER PERFORMANCE RECENTLY.
BOTTOM LINE...A THREAT (PROBABLY A SLIGHT RISK) OF SEVERE
THUNDERSTORMS FRIDAY NIGHT INTO SATURDAY. A BAND OF SHOWERS AND
STORMS SHOULD AFFECT THE ENTIRE REGION FOR 3-6 HOURS TIME STARTING
IN THE WEST BEFORE DAYBREAK SATURDAY... THEN TRACKING SLOWLY EAST
ACROSS CENTRAL NC SATURDAY. QPF OF A HALF INCH TO ONE INCH WILL BE
LIKELY WITH LOCALLY HIGHER TOTALS. TURNING COOLER SATURDAY NIGHT AND
SUNDAY WITH RAIN LIKELY EAST... AND A CHANCE OF RAIN WEST.
ADDITIONAL SIGNIFICANT QPF POSSIBLE MAINLY EAST AND SOUTH. HIGHS
SATURDAY 65-75 NW TO SE. LOWS SATURDAY NIGHT 40S WEST/LOWER 50S SE.
HIGHS HOLDING IN THE 50S SUNDAY.
MONDAY THROUGH WEDNESDAY...
IT APPEARS THAT WE ARE SET TO REVERT BACK TO A DEEPENING MID-UPPER
TROUGH OVER THE WEST-CENTRAL STATES... WITH RISING HEIGHTS ACROSS
THE SE STATES TUE-WED. BEFORE THAT OCCURS... IT APPEARS THAT MONDAY
WILL BE A CHILLY AND VARIABLY CLOUDY DAY AS THE CORE OF THE
MID-UPPER TROUGH IS EXPECTED TO BE OVER THE MID-ATLANTIC STATES.
MODELS ARE INDICATING THE POSSIBILITY OF A FINAL BUT STRONG
VORTICITY MAXIMUM TO ROTATE SE ACROSS NC OR VA MONDAY. DEPENDING ON
THE EVENTUAL TRACK AND STRENGTH OF THIS VORT MAX... WE COULD SEE A
CHANCE OF SHOWERS AGAIN MONDAY. PARTIALS SUGGEST RAIN SHOWERS AND
THE THERMAL PROFILES INDICATE TEMPS SHOULD BE 40+ EVEN IF THE TRACK
IS SOUTH (COLDER FOR US). THEREFORE... ONLY A SMALL CHANCE OF RAIN
SHOWERS WILL BE FORECAST MONDAY.
TUESDAY AND WEDNESDAY APPEAR TO BE IN LINE FOR SUN AND INCREASING
TEMPS AGAIN AFTER A NIGHT OR TWO AT OR BELOW 32.
&&
.AVIATION /06Z THURSDAY THROUGH SUNDAY/...
AS OF 110 AM THURSDAY...
AFTER MAINLY VFR CONDITIONS AS OF 06Z...MOIST LOW LEVEL
SOUTHWESTERLY FLOW WILL PRODUCE A MEDIUM TO HIGH CHANCE OF IFR
CEILINGS BETWEEN 08-14Z THIS MORNING...LIKELY TO LAST LONGEST AT
KRWI AND KFAY. OTHERWISE...THE IMMEDIATE THREAT OF CONVECTION HAS
DIMINISHED...AND THERE IS HIGH UNCERTAINTY REGARDING WHETHER OR NOT
THE PRE-FRONTAL CONVECTION ALONG THE SPINE OF THE BLUE RIDGE WILL
SURVIVE IN THE LEE OF THE MOUNTAINS AND AFFECT CENTRAL NC TERMINALS
BETWEEN 08-12Z. HAVE INCLUDED ONLY TEMPORARY SHOWERS AT TRIAD
TERMINALS TO ACCOUNT FOR THIS POSSIBILITY...BUT SUBSEQUENT
AMENDMENTS MAY BE NECESSARY IF OBSERVATIONAL DATA TRENDS SUGGEST THE
LINE WILL MAINTAIN ITSELF ALL THE WAY THROUGH CENTRAL NC.
OTHERWISE...A BREEZY SOUTHWEST WIND WILL CONTINUE THIS MORNING...IN
STRONG LOW LEVEL FLOW AHEAD OF THE PARENT COLD FRONT THAT WILL
SETTLE SLOWLY THROUGH CENTRAL NC IN DRY FASHION LATER TODAY AND
TONIGHT. CLEARING SKIES WILL ENSUE WITH DAYTIME HEATING AND MIXING
BY 13-15Z...AT WHICH TIME SURFACE WINDS WILL ALSO VEER TO A MORE
WESTERLY COMPONENT...WITH GUSTS INTO THE 20-25 KT RANGE...LATE
MORNING THROUGH SUNSET. ANOTHER STORM SYSTEM WILL RESULT IN A HIGH
PROBABILITY OF SUB-VFR STRATUS AND CONVECTION LATE FRIDAY THROUGH
SATURDAY.
&&
.FIRE WEATHER...
AS OF 315 AM WEDNESDAY...
LITTLE TO NO RAINFALL OCCURRED OVER CENTRAL NC YESTERDAY EVENING
THROUGH THIS MORNING. A DRY FRONT WILL SLOWLY PROGRESS INTO THE AREA
THIS AFTERNOON...EVENTUALLY STALLING NEAR THE SC BORDER TONIGHT. A
DRIER AIRMASS WILL ADVECT INTO THE AREA IN THE WAKE OF THE FRONT
THIS AFTERNOON. RELATIVE HUMIDITY VALUES WILL LIKELY FALL TO 30% OR
LOWER NORTH OF HWY 64. SOUTH OF HWY 64...MINIMUM RH`S THIS AFTERNOON
WILL HIGHLY DEPEND ON THE PROGRESS OF THE FRONT (AND THE DRIER
AIRMASS ADVECTING INTO THE AREA)...AND COULD RANGE ANYWHERE FROM
25-45%...HIGHEST NEAR THE SC BORDER. BREEZY WESTERLY WINDS ARE
EXPECTED TODAY...SUSTAINED AT ~15 MPH WITH GUSTS UP TO 25-30 MPH.
THE COMBINATION OF LOW RH`S...LITTLE OR NO RECENT RAINFALL...AND
BREEZY WESTERLY WINDS WILL RESULT IN AN INCREASED FIRE DANGER THIS
AFTERNOON...ESPECIALLY NORTH OF HWY 64 (IN THE NORTHERN AND NW
PIEDMONT). WILL ISSUE AN INCREASED FIRE DANGER SPS FOR THE NORTHERN
2/3 OF CENTRAL NC...OMITTING THE FAR SOUTHERN TIER OF COUNTIES WHERE
RH`S ARE MORE LIKELY TO REMAIN IN THE 35-45% RANGE. -VINCENT
&&
.RAH WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
SYNOPSIS...VINCENT
NEAR TERM...VINCENT
SHORT TERM...VINCENT
LONG TERM...BADGETT
AVIATION...MWS
FIRE WEATHER...VINCENT
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1234 AM EST THU MAR 1 2012
.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH LATE TONIGHT AND WILL BE OFF THE
COAST THURSDAY. A WARM FRONT WILL LIFT THROUGH FROM THE SOUTH
DURING THE DAY FRIDAY. THE NEXT COLD FRONT WILL PASS THROUGH LATE
SATURDAY NIGHT. HIGH PRESSURE BEHIND THE FRONT WILL BE CENTERED OVER
THE CAROLINAS TUESDAY. THE HIGH WILL MOVE OFF THE COAST BY THE
MIDDLE OF NEXT WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 1230 AM THURSDAY...BROKEN LINE OF SHOWERS AFFECTING THE
COASTAL PLAINS MOVING TOWARD THE SOUNDS COUNTIES CURRENTLY. THERE
HAVE BEEN SOME EMBEDDED LIGHTNING STRIKES AND BRIEF HEAVY
DOWNPOURS WITH A FEW OF THESE CELLS...BUT THE ATMOSPHERE REMAINS
RATHER STABLE ACROSS EASTERN NORTH CAROLINA AND THINK THE SEVERE
THREAT WILL BE LIMITED FOR THE VERY SHORT TERM. STILL SOME CONCERN
WITH AXIS OF INSTABILITY ACROSS CENTRAL GEORGIA AND ALABAMA WHICH
WILL BE DRAWN THIS WAY WITH STRONG 850 MB JET OVER THE NEXT 3 TO 5
HOURS. EXPECTATION IS STILL FOR PRECIP TO MOVE OFFSHORE EARLY ON
THURSDAY MORNING AS AXIS OF HIGHER PRECIPITABLE WATER AND SPECIFIC
HUMIDITY MOVES OFFSHORE BY 12Z OR S0. MADE CHANGE TO LATEST
FORECAST TO RAISE POPS OVER THE NORTHERN AND WESTERN SECTIONS TO
LIKELY AND TO HIGH CHANCE OVER SOUTHERN AREAS AS A LARGE AREA OF
MOSTLY LIGHTER RAINFALL MAY AFFECT THE SOUTHERN COASTAL AREAS IN
THE NEXT 2 TO 4 HOURS.
&&
.SHORT TERM /FRIDAY/...
AS OF 3 PM WED...TIME SECTIONS SHOW DEEP WESTERLY FLOW DURING THE
DAY THURSDAY WITH A VERY DRY AIRMASS. CLOUDS WILL CLEAR OUT IN
THE MORNING WITH MOSTLY SUNNY SKIES IN THE AFTERNOON. ALL THESE
FACTORS WILL COMBINE TO MAKE FOR A VERY WARM DAY. HIGHS WILL RANGE
FROM THE UPPER 60S ON THE OUTER BANKS WITH MID 70S TO AROUND 80
FOR MUCH OF THE INLAND AREAS. A FEW SPOTS ALONG THE COASTAL PLAIN
WILL LIKELY SEE LOWER 80S.
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
AS OF 3 PM WED...DRY AND MILD THU NIGHT AS WEAK HIGH PRES PASSES
ACROSS JUST TO THE N...LOWS MAINLY IN THE 40S. WARM FRONT WILL
LIFT N THRU THE REGION FRI. ALMOST ALL MDLS SHOW DECENT BAND OF
MOISTURE WITH WEAK ISENT UPGLIDE OVER THE THE AREA SO HAVE MAINLY
CHC POP INLAND TO SLIGHT CHC CST BASE ON BLEND OF MDL POPS. WITH
WARM AIR GRAD OVERSPREADING REGION HAVE HIGHS RANGING FROM LOWER
70S SOUTH TO LOWER 60S NE CST. AREA WILL BE IN WARM SECTOR FRI
NIGHT WITH STILL SOME LINGERING SHRA POSS NRN TIER...ESPCLY IN THE
EVENING. LOWS WILL BE WELL ABOVE NORMAL WITH 55 TO 60 MOST SPOTS.
STRONG COLD FRONT AHEAD OF BIG UPR TRF WILL APPROACH SAT AND CROSS
THE REGION SAT NIGHT. WARM AND SOMEWHAT UNSTABLE CONDITIONS
EXPECTED SAT AFTN AHEAD OF THE FRONT WITH INCREASING CHC OF SHRA
AND A FEW TSRA. HAVE CONT PREV TREND OF LIKELY POPS INLAND TO CHC
CST SAT AFTN. STRONG LOW LVL WIND FIELDS COMBINED WITH THE
EXPECTED INSTAB AND FORCING WILL LEAD TO A THREAT OF SOME STRONG
TO POSS SVR STORMS SAT AFTN. FRONT WILL GRAD CROSS THE REGION SAT
NIGHT...GFS STILL A LITTLE FASTER THEN ECMWF BUT BOTH SHOW DEEP
MOISTURE AND LOTS OF RAIN OVER THE AREA SAT NIGHT. HAVE HIGH END
LIKELY POPS ALL AREAS AND RAISED QPF AMOUNTS TO OVER 1/2 INCH.
BOTH GFS AND ECMWF SHOW WELL OVER 1 INCH OF RAIN SAT NIGHT SO
LATER SHIFTS MAY BE ABLE TO RAISE BOTH POP AND QPF AMOUNTS. DEEPER
MOISTURE WILL GRAD SLIDE OFFSHORE SUNDAY WITH RAIN ENDING FROM W
TO E BY LATE MORN. UPR TRF WILL PIVOTS THRU SUN NIGHT AND MON
HOWEVER MOISTURE LOOKS LIMITED WITH NO PRECIP EXPECTED AT THIS
POINT. HGTS ALOFT WILL BE RISING TUE AND WED WITH STRONG SFC HIGH
PRES OVER THE REGION TUE...SLIDING OFFSHORE WED. TEMPS WILL BE
NEAR TO POSS A LITTLE BELOW NORMAL SUN INTO TUE AS UPR TRF
CROSSES. AS HGTS BUILD TEMPS SHLD MODERATE AGAIN MIDDLE PART OF
NEXT WEEK.
&&
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
SHORT TERM /00Z THURSDAY THROUGH 00Z FRIDAY/
AS OF 1235 AM THURSDAY...VERY TRICKY TAF FORECASTS CONTINUE AS
CEILINGS HAVE REMAINED WELL ABOVE 3000 FT AND IN THE VFR FOR MUCH
OF THE DAY. EVEN THE SCATTERED SHOWERS ARE NOT HAVING MUCH EFFECT
ON THE CEILINGS/VSBYS. WILL CARRY A 3-HOUR TEMPO GROUP TO ACCOUNT
FOR THE WIDELY SCATTERED SHOWERS/TSTMS AND PERHAPS A BRIEF DROP IN
CEILINGS TO NEAR MVFR RANGE. SKIES SHOULD CLEAR BY 13Z OR SO WITH
VFR TO PREVAIL THRU THURSDAY NIGHT.
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 3 PM WED...VFR THU NIGHT AS HIGH PRES CROSSES TO THE N. WARM
FRONT WILL LIFT N THRU REGION FRI...THIS WILL LEAD TO INCREASING
CLOUDS WITH WDLY SCT TO SCT SHRA...SOME MVFR CONDITIONS WILL BE
POSS AS LOW LVLS MOISTEN. MORE NUMEROUS SHRA AND POSS A FEW GUSTY
TSRA EXPECTED SAT AFTN AHEAD OF A COLD FRONT WITH PDS OF MVFR OR
IFR EXPECTED. WIDESPREAD IFR EXPECTED TO DEVELOP SAT NIGHT WITH
GOOD CVRG OF RAIN AND COLD AIR ADVECTION IN WAKE OF FRONT. SHRA
AND ASSOC IFR/MVFR SHLD END SUN MORN WITH VFR REST OF THE PERIOD.
&&
.MARINE...
SHORT TERM /TONIGHT AND THURS/
AS OF 1235 AM THURSDAY...SOME GUSTS TO NEAR 25 KNOTS AT DUCK PIER
AND HATTERAS COAST GUARD STATION AT 05Z. THE LATEST RUC13 STILL
SHOWS SW WINDS IN THE 20 TO 25 KNOT RANGE OVER MOST OF THE WATERS
FROM 08Z THRU ABOUT 14Z THIS MORNING. SEAS ARE GENERALLY 6 FEET
OVER SOUTHERN WATERS AND 3 TO 4 FEET UP NORTH. ONLY MINOR CHANGES
TO NEEDED TO CURRENT MARINE FORECAST WHICH HOLDS ON TO A SMALL
CRAFT ADVISORY WHICH EXPIRES ON THE SOUNDS AT 12Z AND ELSEWHERE
THIS AFTERNOON.
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
AS OF 3 PM WED...LIGHT MAINLY NE WINDS WILL DEVELOP THU NIGHT AS
WEAK BNDRY SLIDES OFFSHORE AND HIGH PRES BUILDS IN FROM THE N. AS
HIGH SLIDES OFF THE CST FRI WARM FRONT WILL LIFT N THRU THE REGION
WITH WINDS BECOMING S 10 TO 15 KT. S/SW WINDS WILL GRAD INCREASE
FRI NIGHT AND PEAK SAT AHEAD OF APPROACHING COLD FRONT. SOLID SCA
WINDS EXPECTED MOST WTRS WITH SEAS REACHING 8 TO 9 FT OUTER CNTRL
AND SRN WTRS. FRONT WILL CROSS SAT NIGHT WITH MAINLY NW WINDS 10
TO 20 KTS SUNDAY...SEAS SHLD SUBSIDE BELOW SCA LVLS LATER SAT
NIGHT OR SUNDAY WITH THE DECREASING OFFSHORE FLOW. WNW WINDS WILL
CONT AT 15 TO 20 KTS INTO MON AS INIT HIGH PRES BUILDS TO THE
S...WINDS MAY BECOME MORE NW AT 20 TO 25 KTS LATER MON AS UPR TRF
PIVOTS THRU BUT WILL KEEP BELOW SCA LVLS FOR NOW. SEAS WILL BE
MAINLY 3 TO 5 FT SUN AND MON WITH FAR OUTER CNTRL WTRS FLIRTING
WITH 6 FT.
&&
.MHX WATCHES/WARNINGS/ADVISORIES...
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EST THIS MORNING FOR AMZ135.
SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR AMZ152-
154-156-158.
SMALL CRAFT ADVISORY UNTIL 10 AM EST THIS MORNING FOR AMZ150.
&&
$$
SYNOPSIS...HSA
NEAR TERM...CTC
SHORT TERM...HSA
LONG TERM...RF
AVIATION...CTC/RF
MARINE...CTC/RF
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
715 PM CST FRI MAR 2 2012
.DISCUSSION...WASHKISH WAS REPORTING 1/4SM VSBY FOR THE PAST FEW
HOURS...AND MAKE SOME CALLS TO THAT AREA. IT APPEARS A HEAVY SNOW
BAND SET UP ACROSS NORTHERN BELTRAMI COUNTY AND SOUTHERN LAKE OF
THE WOODS COUNTY AND DROPPED 4-5 INCHES (OF COURSE RADAR
OVERSHOOTS THIS AREA). REPORTS AND OBS INDICATE VSBY IMPROVING...SO
THIS BAND MUST BE BREAKING UP. THIS AREA WAS IN A FAVORABLE
BANDING ENVIRONMENT...SO NOT TOTALLY SURPRISED. MODELS INDICATE
ANOTHER 1-3 INCHES POSSIBLE OVERNIGHT SO ISSUED A WINTER WX
ADVISORY. THESE TOTAL SNOW AMOUNTS ARE CLOSE TO WARNING
CRITERIA...BUT THINK SINCE CURRENT HEAVY BAND IS OVER...AND
REMAINDER OF SNOW WILL FALL OVER A 12 HOUR PERIOD THAT ADVISORY IS
THE WAY TO GO. UPDATED GRIDS AND PRODUCTS HAVE BEEN SENT.
CONDITIONS ARE SLOWLY IMPROVING ACROSS THE OTHER WINTER WX
ADVISORY...BUT STILL SOME REPORTS OF POOR VSBY IN OPEN COUNTRY AND
WILL LET THIS ADVISORY RIDE FOR A WHILE LONGER...ESPECIALLY SINCE
IT IS NOW DARK.
DO NOT PLAN ANOTHER UPDATE UNLESS IT IS NEEDED.
&&
.AVIATION...SLOW PROGRESSION OF SFC LOW AND PRESENCE OF WRAP
AROUND MOISTURE WILL KEEP CIGS/VSBY DOWN INTO MVFR/IFR TERRITORY
THRU THE TAF PERIOD. OTHERWISE...BEHIND THE SYSTEM...BREEZY NORTH
WINDS WILL RESULT IN BLSN WEST OF THE RED RIVER...AND PROGRESSING
EAST THROUGH THE PERIOD.
&&
.PREV DISCUSSION... /ISSUED 501 PM CST FRI MAR 2 2012/
DISCUSSION...WINDS HAVE INCREASED ACROSS MUCH OF EASTERN NORTH
DAKOTA SUSTAINED AROUND 30 MPH. CALLS TO LAW ENFORCEMENT AND WEB
CAMS INDICATE THAT VISIBILITIES IN OPEN COUNTRY ARE 1/2SM OR LESS
AT TIMES ACROSS MUCH OF THE NORTHERN RED RIVER VALLEY DUE TO
MAINLY BLOWING SNOW. THUS...WILL EXPAND THE WINTER WX ADVISORY
INTO THIS AREA FOR BLOWING SNOW. VISIBILITIES REMAIN DECENT ACROSS
THE SOUTHWEST FA...BUT WOULD NOT BE SURPRISED IF BLOWING SNOW
BEGINS TO CAUSE PROBLEMS AS THE TEMPERATURE DROPS (AS IT DID
ACROSS THE NORTH WHEN THE SNOW STARTED BLOWING AROUND). WILL
MONITOR THIS AREA...JUST NOT SURE IF WINDS WILL BE STRONG ENOUGH
BY THE TIME THE TEMPS ACTUALLY DROP.
THE WET ROADS FROM THE AFTERNOON ARE BECOMING ICY AS WELL.
UPDATED FORECAST TO EXPAND AREAS OF BLOWING SNOW INTO THE NEW
ADVISORY AREA...AND PATCHY BLOWING SNOW ACROSS THE SOUTHWEST FA.
INCREASED WIND SPEEDS A BIT. CONTINUED COLD AIR ADVECTION...925MB
WINDS 30-35 KNOTS...AND INCREASED SFC PRESSURE GRADIENT SHOULD
KEEP ELEVATED WINDS THROUGH MIDNIGHT (EVEN WITH LOSS OF SOLAR).
PREV DISCUSSION... /ISSUED 218 PM CST FRI MAR 2 2012/
SHORT TERM...
WINDS INCREASING OVER THE RED RIVER VALLEY THIS AFTERNOON INTO THE
EVENING AND WILL MAINTAIN WINTER WX ADVISORY OVER THE FAR NORTH AS
VSBYS REMAIN POOR. AREAS FROM LANGDON TO CAVALIER AND WALHALLA
RECEIVED AROUND 5 OR 6 INCHES OF FRESH SNOW FROM LAST EVENING INTO
THIS MORNING AND THESE WINDS WILL CONTINUE CAUSE REDUCED
VISIBILITY DUE TO BLOWING SNOW.
CANADIAN AND US RADAR COMPOSITE SHOWS THE MAIN SNOW BANDS NOW
WEAKENING OVER THE AREA WITH JUST LIGHT SNOW CONTINUING TO MOVE
SOUTH AND WRAP AROUND THE 500 MB LOW WHICH IS OVER GRAND FORKS AT
19Z. EXPECT TO SEE CONTINUED LIGHT SNOW INTO THE EVENING WITH A
GRADUAL SPREAD EAST IN TIME AND ENDING FROM THE WEST AS THE NIGHT
PROGRESSES. AN INCH OR SO IN NORTHWEST MN TONIGHT SEEMS REASONABLE
WITH LESS THAN THAT IN OTHER AREAS. FOR THE HEAVIER SNOWPACK AREAS
OF THE SOUTHERN VALLEY BLOWING SNOW SHOULD NOT BE A HUGE ISSUE AS
THE SNOW PACK IS QUITE HEAVY FROM PREV WET SNOW AND SNOWFALL THIS
AFTN-EVE NOT ENOUGH TO CAUSE ISSUES. BUT EVE SHIFT CAN MONITOR.
WINDS WILL BE GUSTY TO 35 MPH AT TIMES...WITH RUC AND OTHER SHORT
TERM MODELS SHOWING MIXING UP TO NR 925 MB WHERE WINDS WILL BE
30-35 KTS THRU 06Z. BORDERLINE WIND ADVISORY....BUT SUSTAINED
LIKELY JUST BLO THRESHOLDS.
WEAK RIDGE OF HIGH PRESSURE WILL BUILD EAST INTO ERN ND SATURDAY
WITH SOME CLEARING EXPECTED OVER ERN ND INTO THE VALLEY. DEPARTING
SYSTEM WILL GENERATE LEFTOVER LIGHT SNOW/FLURRIES IN FAR EASTERN
FCST AREA UNTIL NOON. HIGH PRESSURE WILL MOVE INTO MN SAT NIGHT.
DID REMOVE THE WIDESPREAD LOW POPS WE HAD IN THE FCST FOR ERN ND
INTO THE RED RIVER VALLEY SATURDAY AND REMOVED POPS FOR NW MN SAT
AFTN-NIGHT. WITH HIGH OVERHEAD AND POTENTIAL FOR CLEARING LOOKS
CHILLY AT NIGHT WITH OVERNIGHT LOWS SAT NIGHT IN THE SINGLE DIGITS
IN MANY AREAS.
NEXT THREAT FOR SOME LIGHT SNOW WILL BE OVERNIGHT SATURDAY NIGHT
AND INTO SUNDAY MAINLY OVER ERN ND INTO THE SRN VALLEY AS A WEAK
SHORT WAVE DROPS THRU CNTRL ND INTO ERN SD/SW MN. PRECIP WITH THIS
SYSTEM QUITE WEAK.
HIGH PRESSURE TO BUILD IN SUN NIGHT THEN WINDS WILL TURN SOUTH-
SOUTHWEST ON MONDAY AS A STORM SYSTEM GATHERS STRENGTH OVER
ALBERTA. THIS SHOULD BRING MILDER AIR INTO THE REGION.
LONG TERM (MON NIGHT-FRI)...
MODELS INITIALIZED WELL THIS RUN...BUT SOME DIFFERENCES SHOWING UP
IN PLACEMENT OF THE SFC FRONT FOR TUESDAY. OVERALL TRENDS STILL LOOK
GOOD FOR SHIFT TO A PROGRESSIVE PATTERN THROUGH THE END OF THE
PERIOD. THUS...CONTINUED TO LOOK AT A BLEND FOR THE GENERAL TIMING
OF THE FEATURES. THE 500HPA RIDGE IS EXPECTED TO SHIFT EAST WITH
THICKNESS VALUES INCREASING...SO EXPECTING TEMPS TO BE NEAR OR
SLIGHTLY ABOVE SEASONAL NORMS. BY THE END OF THE PERIOD...LOOK FOR
ANOTHER COLD FRONTAL PASSAGE...WITH ANOTHER CHANCE FOR MEASURABLE
PCPN.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR
NDZ006>008-014>016-024-026>030-054.
MN...WINTER WEATHER ADVISORY UNTIL MIDNIGHT CST TONIGHT FOR MNZ001-
004-007.
WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR MNZ006-009.
&&
$$
TG
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
615 PM EST FRI MAR 2 2012
.SYNOPSIS...
SHOWERS AND THUNDERSTORMS WITH COLD FRONT LATE FRIDAY...SOME STORMS
COULD BE STRONG TO SEVERE. COOLER WEATHER ESTABLISHES FOR THE
WEEKEND INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH SATURDAY/...
SHOWERS AND THUNDERSTORMS ASSOCIATED WITH AN APPROACHING WARM FRONT
AND MOISTURE PUNCH HAVE BEEN ONGOING ACROSS THE FORECAST AREA SINCE
MID MORNING. WRFNMM...HRRR...AND CURRENT RADAR HAVE SOME SMALL
TIMING DIFFERENCES...HOWEVER ALL AGREE THAT THERE WILL BE A BREAK IN
THE SHOWERS AND STORMS FOLLOWING THE WARM FRONT...PRIOR TO THE COLD
FRONT ARRIVING LATER THIS EVENING. RECENT RUC BUFKIT SOUNDINGS SHOW
JUST OVER 500J/KG CAPE IN EASTERN KY/WESTERN WV AHEAD OF THE COLD
FRONT LATER THIS EVENING...SO STILL THINKING STRONG TO SEVERE
THUNDERSTORMS POSSIBLE AHEAD OF THE FRONT. WITH THE TIME OF DAY THE
STORMS ARE EXPECTED...WE MAY SEE DECREASING THERMODYNAMICS AS THE
STORMS MOVE INTO CENTRAL WV. HOWEVER WITH PLENTY OF SHEAR AND
DYNAMIC LIFT FROM THE FRONT...STORMS SHOULD STILL BE ABLE TO SUPPORT
DAMAGING WINDS AND HAIL...AND POSSIBLY AN ISOLATED TORNADO.
COLD FRONT PASSAGE EXPECTED FROM FROM NW TO SE AROUND 03-06Z
TONIGHT. PRECIP CHANCES DECREASE QUICKLY AFTER THE FRONT MOVES
THROUGH.
NOT A REAL STRONG COLD PUNCH IMMEDIATELY AFTER THE FRONT...AND WITH
SOME GUSTY WINDS HANGING AROUND...WILL REMAINED WELL MIXED SO TEMPS
SHOULD REMAIN FAIRLY STEADY MOST OF THE NIGHT WITH A GRADUALLY
DECREASE THROUGH THE EARLY MORNING HOURS. TRENDED TOWARDS THE MET
AND THEN MADE SOME MINOR TWEAKS TO HOLD THE TEMPS STEADIER AT FIRST.
&&
.SHORT TERM /SATURDAY NIGHT/...
CAA REGIME SETTING UP FOR THE WEEKEND. SAT SHOULD SEE SUN EARLY
BEFORE STRONGER CAA LATE IN THE DAY ALLOWS FOR STRATOCU AND CU TO
DEVELOP AS UPR TROF PIVOTS IN. DESPITE H85 TEMPS -2 TO -6....THINK
ENOUGH MIXING WILL OCCUR FOR THE WARMER NUMBERS OFF GUIDANCE TO
BECOME REALIZED. FLOW COMES MORE CONDUCIVE FOR UPSLOPE SUN INTO SUN
NIGHT AS UPR TROF AXIS SWINGS THRU. INHERITED SNOW/POP GRIDS
GENERALLY LOOKED GOOD AND ONLY NEEDED SOME FINESSING. ALLOWED FOR A
HIGH THRESHOLD FOR RAIN/SNOW DURING DAY SUN BASED ON TEMPS ALOFT.
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
THIS PERIOD WILL BE CHARACTERIZED BY AN EXITING UPPER LEVEL
SHORTWAVE WITH UPPER LEVEL RIDGING BUILDING IN TUE...FOLLOWED BY THE
POSSIBILITY OF A COLD FRONT IN THE AREA LATE IN THE PERIOD.
EXTENDED MODEL GUIDANCE IS IN GOOD AGREEMENT MON EVE-WED...DEPICTING
THE EXITING SHORTWAVE WHICH WILL AFFECT OUR AREA SUN-EARLY MON
FOLLOWED BY UPPER LEVEL RIDGING OVER THE EASTERN CONUS TUE-WED.
THOUGH TUE MORNING WILL BE RATHER COLD...THE PERIOD WILL BE DRY WITH
A WARMING TREND BEGINNING TUE AFTERNOON. BY LATE WED MODEL OUTPUT
BEGINS TO DIFFER WITH RESPECT TO THE SPEED OF AN UPPER LEVEL TROUGH
DIGGING SOUTHEASTWARD ACROSS THE NORTH CENTRAL U.S. AND ITS
ASSOCIATED COLD FRONT. THE GFS DEPICTS A MUCH QUICKER PROGRESSION
WITH COLD FRONT ABOUT OVER OUR FORECAST AREA BY 06Z-12Z THU WITH
NICE WEATHER FRI...WHILE THE EC SHOWS A MUCH SLOWER PROGRESSION WITH
THE COLD FRONT OVER THE AREA FRIDAY. GFS ENSEMBLE MEAN AND ITS
MEMBERS...AND TO A LESSER EXTENT THE CANADIAN...IN MUCH BETTER
AGREEMENT WITH SLOWER SOLUTION AND WILL THUS LEAN THE FORECAST FOR
THIS TIME FRAME TOWARDS THE EC WITH THURSDAY HAVING AN INCREASE IN
HIGH CIRRUS WITH THE NEXT SHOT A SHOWERS COMING ON FRIDAY WITH THE
FRONT.
&&
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
SHOWERS AND THUNDERSTORMS ONGOING ACROSS FORECAST AREA. THESE ARE
AHEAD OF A COLD FRONT WHICH WILL COME THROUGH LATE THIS EVENING...
INTO THE OVERNIGHT HOURS...WITH STRONG TO SEVERE STORMS. STRONG GUSTY
WINDS AND HAIL SHOULD BE THE MAIN THREAT. SHOWERS AND THUNDERSTORMS
SHOULD DIMINISH PRETTY RAPIDLY AFTER THE COLD FRONT MOVES THROUGH.
THE ENTIRE REGION SHOULD BE PRECIPITATION-FREE BY 09Z.
OUTSIDE OF THE PRECIPITATION...VFR CONDITIONS SHOULD BE COMMON.
HOWEVER...MVFR OR EVEN IFR CONDITIONS ARE POSSIBLE IN THE THUNDERSTORMS,
AHEAD OF THE FRONT...GUSTY SOUTHERLY WINDS ARE EXPECTED...WITH THE
WIND BECOMING SOUTHWESTERLY AND FINALLY WESTERLY AFTER THE FRONT
PUSHES EAST.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z SUNDAY...
FORECAST CONFIDENCE: MEDIUM.
ALTERNATE SCENARIOS: UNCERTAINTY REMAINS ON EXACT TIMING AND
LOCATIONS OF STRONGEST CONVECTION AND RELATED MVFR AND IFR
CONDITIONS. TEMPOS MAY BE NEEDED FOR BRIEF IFR...GUSTY THUNDERSTORM
WINDS...AND HEAVY RAIN/THUNDERSTORMS.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE SAT
UTC 1HRLY 00 01 02 03 04 05 06 07 08 09 10 11
EST 1HRLY 19 20 21 22 23 00 01 02 03 04 05 06
CRW CONSISTENCY H H M M L M H M M M M M
HTS CONSISTENCY H H L M M M L M M M H H
BKW CONSISTENCY L L M M M L L M M H H H
EKN CONSISTENCY L L M M L M M M M M M M
PKB CONSISTENCY H H L L L M M M M M M M
CKB CONSISTENCY H H M L L M M M M M M M
AFTER 00Z SUNDAY...
MVFR TO IFR POSSIBLE IN MOUNTAIN SNOW SHOWERS SATURDAY EVENING THROUGH
SUNDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...FLASH FLOOD WATCH UNTIL 6 AM EST SATURDAY FOR WVZ005>011-
013>020-024>040-046-047.
OH...FLASH FLOOD WATCH UNTIL 6 AM EST SATURDAY FOR OHZ067-075-076-
085>087.
KY...FLASH FLOOD WATCH UNTIL 6 AM EST SATURDAY FOR KYZ101>103-105.
VA...FLASH FLOOD WATCH UNTIL 6 AM EST SATURDAY FOR VAZ003-004.
&&
$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...JSH
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
113 PM EST THU MAR 1 2012
.SYNOPSIS...
A RIDGE WILL BUILD INTO THE AREA TODAY AND THEN MOVE EAST TONIGHT
AS A STRONG COLD FRONT MOVES THROUGH FRIDAY EVENING. A TROUGH WILL
MOVE THROUGH THE EASTERN LAKES ON SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FORECAST CONTINUES TO LOOK GOOD SO NO CHANGES NEEDED FOR 1230 PM
UPDATE.
TEMPS RUNNING A FEW DEGREES COOLER THAN EXPECTED EARLIER SO WILL
MAKE THIS ADJUSTMENT. HRRR AS USUAL SHOW NUMEROUS CELLS OF PRECIP
OVER THE AREA TODAY WITH STRATOCU FIELD. COULD SEE SOME SPRINKLES
OR FLURRIES OUTSIDE OF THE SNOWBELT SO WILL ADD MENTION OF THIS
WITHOUT HAVING TO INCREASE POPS SINCE COULD BE HARD TO SEE
ANYTHING MEASURABLE.
IN THE SNOWBELT...A LITTLE LAKE ENHANCEMENT WILL KEEP A THREAT
FOR SHOWERS. TEMPS MARGINAL FOR RAIN OR SNOW THROUGHOUT THE DAY.
DON`T THINK THERE WILL BE ENOUGH SNOWFALL FOR ANY ACCUMULATION OF
SIGNIFICANCE. WINDS GUSTING TO 30 MPH WILL GRADUALLY DIMINISH.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
THE CLOUDS WILL DECREASE TONIGHT AS THE FLOW BECOMES SOUTH. ON THE
EDGE ABOUT THE TIMING OF THE FRONT FOR FRIDAY EVENING. THE GFS
MOISTURE SEEMS SCANT BUT IT MAY HAVE THE RIGHT IDEA. ALSO IF THE
PRECIPITATION STARTS EARLY IT MAY AFFECT THE HIGHS ON FRIDAY. THE
850 MB TEMPERATURE IS EXPECTED TO BE ABOUT THE SAME AS IT WAS ON
WEDNESDAY WHEN MANY LOCATIONS HAD RECORD HIGHS. SOME RECORD HIGHS
COULD BE APPROACHED ESPECIALLY OVER NORTHWEST AND NORTH CENTRAL
OHIO. THE AREA IS IN A SLIGHT RISK FOR FRIDAY. WILL MENTION THAT
IN THE HWO. WINDS COULD APPROACH WIND ADVISORY CRITERIA BEHIND THE
COLD FRONT FRIDAY NIGHT. THIS WILL ALSO BE MENTIONED IN THE HWO.
SOME LAKE EFFECT SNOW SHOWERS DEVELOP ON SATURDAY AND CONTINUE
INTO SUNDAY. THE SNOW SHOWERS BECOME A LITTLE MORE WIDESPREAD
SUNDAY AS A TROUGH MOVES THROUGH. ON THE EDGE ABOUT THE SNOWFALL
AMOUNTS...IT IS POSSIBLE THAT AN ADVISORY FOR SNOW MAY BE NEEDED
FOR THE SNOW BELT.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
HIGH A LITTLE SLOWER BUILDING IN ON WEDNESDAY SO KEPT CHANCE POPS
GOING INTO MONDAY. MODELS CONTINUE TO BE IN GOOD AGREEMENT MOVING
HIGH ACROSS THE LOWER LAKES/OHIO VALLEY MONDAY INTO TUESDAY THEN
MOVING THE HIGH OFF THE EAST COAST ON WEDNESDAY. MODELS CONTINUE TO
BRING THE NEXT SYSTEM ACROSS THE AREA ON THURSDAY...BUT GFS
CONTINUES TO BE THE FASTER OF THE 2 MODELS. GFS BRING THE FRONT
INTO THE CENTRAL PART OF THE FORECAST AREA BY 12Z THURSDAY...WHILE
THE ECMWF BRINGS THE FRONT THROUGH DURING THE DAY ON THURSDAY.
LEANED TOWARD THE SLOWER ECMWF FOR THIS FORECAST.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
TYPICAL WINTER TIME CONDITIONS THIS AFTERNOON WITH MVFR CIGS OVER
THE GREAT LAKES WITH A SURFACE LOW OVER SOUTHERN ONTARIO WITH A
HIGH PRESSURE RIDGE FROM IOWA SE INTO ALABAMA. THE RIDGE WILL
GRADUALLY SHIFT EAST OVER THE REGION OVERNIGHT AND ALLOW SLOW
CLEARING TO PROGRESS ACROSS ALL BUT THE EASTERN TAF SITES BY
SUNRISE. CLEARING WILL BE BRIEF AS MOISTURE RAPIDLY RETURNS FROM THE
GULF ON FRIDAY. EXPECT MVFR CIGS TO DEVELOP AGAIN FRIDAY AFTERNOON
ALONG WITH SHOWERS AND THUNDERSTORMS.
OUTLOOK...NON-VFR POSSIBLE FRIDAY EVENING WITH THUNDERSTORMS SOME
MAY BE STRONG TO SEVERE. SNOW SHOWERS RETURNS SUNDAY INTO
MONDAY...BEST CHANCE IN THE SNOWBELT EAST OF CLEVELAND.
&&
.MARINE...
THE SMALL CRAFT ADVISORY HAS BEEN ALLOWED TO EXPIRE WEST OF THE
ISLANDS WITH WINDS ALREADY DOWN TO 15 TO 20 KNOTS AND WINDS
EXPECTED TO CONTINUE DECREASING THROUGH THE AFTERNOON.
PREVIOUS DISCUSSION...EXPECT SMALL CRAFT TO BE NEEDED IN THE EAST
UNTIL LATE THIS EVENING. HIGH PRESSURE MOVES QUICKLY ACROSS THE
LAKE TONIGHT SETTING UP FOR THE NEXT SYSTEM THIS WEEKEND. MODELS
IN GOOD AGREEMENT LIFTING ANOTHER LOW PRESSURE SYSTEM NE ACROSS
THE CENTRAL LAKES FRIDAY NIGHT...DRAGGING ANOTHER COLD FRONT
ACROSS THE LAKE. MODELS DO DIFFER ON THE EXACT STRENGTH AND TRACK
OF THE LOW. WILL DEFINITELY NEED A SMALL CRAFT ADVISORY AGAIN
SATURDAY AND SUNDAY. CURRENT FORECAST HAS 30 KNOT WINDS...BUT 35
KNOT GALES ARE NOT OUT OF THE QUESTION. WILL NEED TO CONTINUE TO
MONITOR.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR
LEZ145>149.
&&
$$
SYNOPSIS...KIELTYKA
NEAR TERM...ADAMS/KIELTYKA
SHORT TERM...KIELTYKA
LONG TERM...DJB
AVIATION...REL
MARINE...KEC
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1206 PM EST THU MAR 1 2012
.SYNOPSIS...
A RIDGE WILL BUILD INTO THE AREA TODAY AND THEN MOVE EAST TONIGHT
AS A STRONG COLD FRONT MOVES THROUGH FRIDAY EVENING. A TROUGH WILL
MOVE THROUGH THE EASTERN LAKES ON SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
FORECAST CONTINUES TO LOOK GOOD SO NO CHANGES NEEDED FOR 1230 PM
UPDATE.
TEMPS RUNNING A FEW DEGREES COOLER THAN EXPECTED EARLIER SO WILL
MAKE THIS ADJUSTMENT. HRRR AS USUAL SHOW NUMEROUS CELLS OF PRECIP
OVER THE AREA TODAY WITH STRATOCU FIELD. COULD SEE SOME SPRINKLES
OR FLURRIES OUTSIDE OF THE SNOWBELT SO WILL ADD MENTION OF THIS
WITHOUT HAVING TO INCREASE POPS SINCE COULD BE HARD TO SEE
ANYTHING MEASURABLE.
IN THE SNOWBELT...A LITTLE LAKE ENHANCEMENT WILL KEEP A THREAT
FOR SHOWERS. TEMPS MARGINAL FOR RAIN OR SNOW THROUGHOUT THE DAY.
DON`T THINK THERE WILL BE ENOUGH SNOWFALL FOR ANY ACCUMULATION OF
SIGNIFICANCE. WINDS GUSTING TO 30 MPH WILL GRADUALLY DIMINISH.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
THE CLOUDS WILL DECREASE TONIGHT AS THE FLOW BECOMES SOUTH. ON THE
EDGE ABOUT THE TIMING OF THE FRONT FOR FRIDAY EVENING. THE GFS
MOISTURE SEEMS SCANT BUT IT MAY HAVE THE RIGHT IDEA. ALSO IF THE
PRECIPITATION STARTS EARLY IT MAY AFFECT THE HIGHS ON FRIDAY. THE
850 MB TEMPERATURE IS EXPECTED TO BE ABOUT THE SAME AS IT WAS ON
WEDNESDAY WHEN MANY LOCATIONS HAD RECORD HIGHS. SOME RECORD HIGHS
COULD BE APPROACHED ESPECIALLY OVER NORTHWEST AND NORTH CENTRAL
OHIO. THE AREA IS IN A SLIGHT RISK FOR FRIDAY. WILL MENTION THAT
IN THE HWO. WINDS COULD APPROACH WIND ADVISORY CRITERIA BEHIND THE
COLD FRONT FRIDAY NIGHT. THIS WILL ALSO BE MENTIONED IN THE HWO.
SOME LAKE EFFECT SNOW SHOWERS DEVELOP ON SATURDAY AND CONTINUE
INTO SUNDAY. THE SNOW SHOWERS BECOME A LITTLE MORE WIDESPREAD
SUNDAY AS A TROUGH MOVES THROUGH. ON THE EDGE ABOUT THE SNOWFALL
AMOUNTS...IT IS POSSIBLE THAT AN ADVISORY FOR SNOW MAY BE NEEDED
FOR THE SNOW BELT.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
HIGH A LITTLE SLOWER BUILDING IN ON WEDNESDAY SO KEPT CHANCE POPS
GOING INTO MONDAY. MODELS CONTINUE TO BE IN GOOD AGREEMENT MOVING
HIGH ACROSS THE LOWER LAKES/OHIO VALLEY MONDAY INTO TUESDAY THEN
MOVING THE HIGH OFF THE EAST COAST ON WEDNESDAY. MODELS CONTINUE TO
BRING THE NEXT SYSTEM ACROSS THE AREA ON THURSDAY...BUT GFS
CONTINUES TO BE THE FASTER OF THE 2 MODELS. GFS BRING THE FRONT
INTO THE CENTRAL PART OF THE FORECAST AREA BY 12Z THURSDAY...WHILE
THE ECMWF BRINGS THE FRONT THROUGH DURING THE DAY ON THURSDAY.
LEANED TOWARD THE SLOWER ECMWF FOR THIS FORECAST.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
LOW PRESSURE SYSTEM OVER THE CENTRAL LAKES WITH OVERCAST MVFR CIGS
BACK INTO IOWA. MVFR CIGS THIS MORNING WILL SLOWLY RISE TO VFR FOR
A TIME LATER THIS AFTERNOON.
IN ADDITION...COLD FRONT THROUGH AREA...AS A RESULT WILL HAVE
GUSTY W-SW WINDS UNTIL LATE AFTERNOON. EXPECT WIND GUSTS UP NEAR
30 KNOTS THIS MORNING...WITH WINDS VERY SLOWLY DIMINISHING
THROUGH THE DAY.
OUTLOOK...NON-VFR POSSIBLE FRIDAY EVENING WITH THUNDERSTORMS SOME
MAY BE STRONG TO SEVERE. SCATTERED RAIN SHOWERS SATURDAY. SNOW
RETURNS SUNDAY INTO MONDAY...BEST CHANCE IN THE SNOWBELT EAST OF
CLEVELAND.
&&
.MARINE...
THE SMALL CRAFT ADVISORY HAS BEEN ALLOWED TO EXPIRE WEST OF THE
ISLANDS WITH WINDS ALREADY DOWN TO 15 TO 20 KNOTS AND WINDS
EXPECTED TO CONTINUE DECREASING THROUGH THE AFTERNOON.
PREVIOUS DISCUSSION...EXPECT SMALL CRAFT TO BE NEEDED IN THE EAST
UNTIL LATE THIS EVENING. HIGH PRESSURE MOVES QUICKLY ACROSS THE
LAKE TONIGHT SETTING UP FOR THE NEXT SYSTEM THIS WEEKEND. MODELS
IN GOOD AGREEMENT LIFTING ANOTHER LOW PRESSURE SYSTEM NE ACROSS
THE CENTRAL LAKES FRIDAY NIGHT...DRAGGING ANOTHER COLD FRONT
ACROSS THE LAKE. MODELS DO DIFFER ON THE EXACT STRENGTH AND TRACK
OF THE LOW. WILL DEFINITELY NEED A SMALL CRAFT ADVISORY AGAIN
SATURDAY AND SUNDAY. CURRENT FORECAST HAS 30 KNOT WINDS...BUT 35
KNOT GALES ARE NOT OUT OF THE QUESTION. WILL NEED TO CONTINUE TO
MONITOR.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR
LEZ145>149.
&&
$$
SYNOPSIS...KIELTYKA
NEAR TERM...ADAMS/KIELTYKA
SHORT TERM...KIELTYKA
LONG TERM...DJB
AVIATION...DJB
MARINE...KEC
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1108 AM EST THU MAR 1 2012
.SYNOPSIS...
A RIDGE WILL BUILD INTO THE AREA TODAY AND THEN MOVE EAST TONIGHT
AS A STRONG COLD FRONT MOVES THROUGH FRIDAY EVENING. A TROUGH WILL
MOVE THROUGH THE EASTERN LAKES ON SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
TEMPS RUNNING A FEW DEGREES COOLER THAN EXPECTED EARLIER SO WILL
MAKE THIS ADJUSTMENT. HRRR AS USUAL SHOW NUMEROUS CELLS OF PRECIP
OVER THE AREA TODAY WITH STRATOCU FIELD. COULD SEE SOME SPRINKLES
OR FLURRIES OUTSIDE OF THE SNOWBELT SO WILL ADD MENTION OF THIS
WITHOUT HAVING TO INCREASE POPS SINCE COULD BE HARD TO SEE
ANYTHING MEASURABLE.
IN THE SNOWBELT...A LITTLE LAKE ENHANCEMENT WILL KEEP A THREAT
FOR SHOWERS. TEMPS MARGINAL FOR RAIN OR SNOW THROUGHOUT THE DAY.
DON`T THINK THERE WILL BE ENOUGH SNOWFALL FOR ANY ACCUMULATION OF
SIGNIFICANCE. WINDS GUSTING TO 30 MPH WILL GRADUALLY DIMINISH.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
THE CLOUDS WILL DECREASE TONIGHT AS THE FLOW BECOMES SOUTH. ON THE
EDGE ABOUT THE TIMING OF THE FRONT FOR FRIDAY EVENING. THE GFS
MOISTURE SEEMS SCANT BUT IT MAY HAVE THE RIGHT IDEA. ALSO IF THE
PRECIPITATION STARTS EARLY IT MAY AFFECT THE HIGHS ON FRIDAY. THE
850 MB TEMPERATURE IS EXPECTED TO BE ABOUT THE SAME AS IT WAS ON
WEDNESDAY WHEN MANY LOCATIONS HAD RECORD HIGHS. SOME RECORD HIGHS
COULD BE APPROACHED ESPECIALLY OVER NORTHWEST AND NORTH CENTRAL
OHIO. THE AREA IS IN A SLIGHT RISK FOR FRIDAY. WILL MENTION THAT
IN THE HWO. WINDS COULD APPROACH WIND ADVISORY CRITERIA BEHIND THE
COLD FRONT FRIDAY NIGHT. THIS WILL ALSO BE MENTIONED IN THE HWO.
SOME LAKE EFFECT SNOW SHOWERS DEVELOP ON SATURDAY AND CONTINUE
INTO SUNDAY. THE SNOW SHOWERS BECOME A LITTLE MORE WIDESPREAD
SUNDAY AS A TROUGH MOVES THROUGH. ON THE EDGE ABOUT THE SNOWFALL
AMOUNTS...IT IS POSSIBLE THAT AN ADVISORY FOR SNOW MAY BE NEEDED
FOR THE SNOW BELT.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
HIGH A LITTLE SLOWER BUILDING IN ON WEDNESDAY SO KEPT CHANCE POPS
GOING INTO MONDAY. MODELS CONTINUE TO BE IN GOOD AGREEMENT MOVING
HIGH ACROSS THE LOWER LAKES/OHIO VALLEY MONDAY INTO TUESDAY THEN
MOVING THE HIGH OFF THE EAST COAST ON WEDNESDAY. MODELS CONTINUE TO
BRING THE NEXT SYSTEM ACROSS THE AREA ON THURSDAY...BUT GFS
CONTINUES TO BE THE FASTER OF THE 2 MODELS. GFS BRING THE FRONT
INTO THE CENTRAL PART OF THE FORECAST AREA BY 12Z THURSDAY...WHILE
THE ECMWF BRINGS THE FRONT THROUGH DURING THE DAY ON THURSDAY.
LEANED TOWARD THE SLOWER ECMWF FOR THIS FORECAST.
&&
.AVIATION /16Z THURSDAY THROUGH MONDAY/...
LOW PRESSURE SYSTEM OVER THE CENTRAL LAKES WITH OVERCAST MVFR CIGS
BACK INTO IOWA. MVFR CIGS THIS MORNING WILL SLOWLY RISE TO VFR FOR
A TIME LATER THIS AFTERNOON.
IN ADDITION...COLD FRONT THROUGH AREA...AS A RESULT WILL HAVE
GUSTY W-SW WINDS UNTIL LATE AFTERNOON. EXPECT WIND GUSTS UP NEAR
30 KNOTS THIS MORNING...WITH WINDS VERY SLOWLY DIMINISHING
THROUGH THE DAY.
OUTLOOK...NON-VFR POSSIBLE FRIDAY EVENING WITH THUNDERSTORMS SOME
MAY BE STRONG TO SEVERE. SCATTERED RAIN SHOWERS SATURDAY. SNOW
RETURNS SUNDAY INTO MONDAY...BEST CHANCE IN THE SNOWBELT EAST OF
CLEVELAND.
&&
.MARINE...
THE SMALL CRAFT ADVISORY HAS BEEN ALLOWED TO EXPIRE WEST OF THE
ISLANDS WITH WINDS ALREADY DOWN TO 15 TO 20 KNOTS AND WINDS
EXPECTED TO CONTINUE DECREASING THROUGH THE AFTERNOON.
PREVIOUS DISCUSSION...EXPECT SMALL CRAFT TO BE NEEDED IN THE EAST
UNTIL LATE THIS EVENING. HIGH PRESSURE MOVES QUICKLY ACROSS THE
LAKE TONIGHT SETTING UP FOR THE NEXT SYSTEM THIS WEEKEND. MODELS
IN GOOD AGREEMENT LIFTING ANOTHER LOW PRESSURE SYSTEM NE ACROSS
THE CENTRAL LAKES FRIDAY NIGHT...DRAGGING ANOTHER COLD FRONT
ACROSS THE LAKE. MODELS DO DIFFER ON THE EXACT STRENGTH AND TRACK
OF THE LOW. WILL DEFINITELY NEED A SMALL CRAFT ADVISORY AGAIN
SATURDAY AND SUNDAY. CURRENT FORECAST HAS 30 KNOT WINDS...BUT 35
KNOT GALES ARE NOT OUT OF THE QUESTION. WILL NEED TO CONTINUE TO
MONITOR.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR
LEZ145>149.
&&
$$
SYNOPSIS...KIELTYKA
NEAR TERM...ADAMS/KIELTYKA
SHORT TERM...KIELTYKA
LONG TERM...DJB
AVIATION...DJB
MARINE...KEC/DJB
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
915 AM EST THU MAR 1 2012
.SYNOPSIS...
A RIDGE WILL BUILD INTO THE AREA TODAY AND THEN MOVE EAST TONIGHT
AS A STRONG COLD FRONT MOVES THROUGH FRIDAY EVENING. A TROUGH WILL
MOVE THROUGH THE EASTERN LAKES ON SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
TEMPS RUNNING A FEW DEGREES COOLER THAN EXPECTED EARLIER SO WILL
MAKE THIS ADJUSTMENT. HRRR AS USUAL SHOW NUMEROUS CELLS OF PRECIP
OVER THE AREA TODAY WITH STRATOCU FIELD. COULD SEE SOME SPRINKLES
OR FLURRIES OUTSIDE OF THE SNOWBELT SO WILL ADD MENTION OF THIS
WITHOUT HAVING TO INCREASE POPS SINCE COULD BE HARD TO SEE
ANYTHING MEASURABLE.
IN THE SNOWBELT...A LITTLE LAKE ENHANCEMENT WILL KEEP A THREAT
FOR SHOWERS. TEMPS MARGINAL FOR RAIN OR SNOW THROUGHOUT THE DAY.
DON`T THINK THERE WILL BE ENOUGH SNOWFALL FOR ANY ACCUMULATION OF
SIGNIFICANCE. WINDS GUSTING TO 30 MPH WILL GRADUALLY DIMINISH.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
THE CLOUDS WILL DECREASE TONIGHT AS THE FLOW BECOMES SOUTH. ON THE
EDGE ABOUT THE TIMING OF THE FRONT FOR FRIDAY EVENING. THE GFS
MOISTURE SEEMS SCANT BUT IT MAY HAVE THE RIGHT IDEA. ALSO IF THE
PRECIPITATION STARTS EARLY IT MAY AFFECT THE HIGHS ON FRIDAY. THE
850 MB TEMPERATURE IS EXPECTED TO BE ABOUT THE SAME AS IT WAS ON
WEDNESDAY WHEN MANY LOCATIONS HAD RECORD HIGHS. SOME RECORD HIGHS
COULD BE APPROACHED ESPECIALLY OVER NORTHWEST AND NORTH CENTRAL
OHIO. THE AREA IS IN A SLIGHT RISK FOR FRIDAY. WILL MENTION THAT
IN THE HWO. WINDS COULD APPROACH WIND ADVISORY CRITERIA BEHIND THE
COLD FRONT FRIDAY NIGHT. THIS WILL ALSO BE MENTIONED IN THE HWO.
SOME LAKE EFFECT SNOW SHOWERS DEVELOP ON SATURDAY AND CONTINUE
INTO SUNDAY. THE SNOW SHOWERS BECOME A LITTLE MORE WIDESPREAD
SUNDAY AS A TROUGH MOVES THROUGH. ON THE EDGE ABOUT THE SNOWFALL
AMOUNTS...IT IS POSSIBLE THAT AN ADVISORY FOR SNOW MAY BE NEEDED
FOR THE SNOW BELT.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
HIGH A LITTLE SLOWER BUILDING IN ON WEDNESDAY SO KEPT CHANCE POPS
GOING INTO MONDAY. MODELS CONTINUE TO BE IN GOOD AGREEMENT MOVING
HIGH ACROSS THE LOWER LAKES/OHIO VALLEY MONDAY INTO TUESDAY THEN
MOVING THE HIGH OFF THE EAST COAST ON WEDNESDAY. MODELS CONTINUE TO
BRING THE NEXT SYSTEM ACROSS THE AREA ON THURSDAY...BUT GFS
CONTINUES TO BE THE FASTER OF THE 2 MODELS. GFS BRING THE FRONT
INTO THE CENTRAL PART OF THE FORECAST AREA BY 12Z THURSDAY...WHILE
THE ECMWF BRINGS THE FRONT THROUGH DURING THE DAY ON THURSDAY.
LEANED TOWARD THE SLOWER ECMWF FOR THIS FORECAST.
&&
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
LOW PRESSURE SYSTEM OVER THE CENTRAL LAKES WITH OVERCAST MVFR CIGS
BACK INTO IOWA. MVFR CIGS THIS MORNING WILL SLOWLY RISE TO VFR FOR
A TIME LATER THIS AFTERNOON.
IN ADDITION...COLD FRONT THROUGH AREA...AS A RESULT WILL HAVE
GUSTY W-SW WINDS UNTIL LATE AFTERNOON. EXPECT WIND GUSTS UP NEAR
30 KNOTS THIS MORNING...WITH WINDS VERY SLOWLY DIMINISHING
THROUGH THE DAY.
OUTLOOK...NON-VFR POSSIBLE FRIDAY EVENING WITH THUNDERSTORMS SOME
MAY BE STRONG TO SEVERE. SCATTERED RAIN SHOWERS SATURDAY. SNOW
RETURNS SUNDAY INTO MONDAY...BEST CHANCE IN THE SNOWBELT EAST OF
CLEVELAND.
&&
.MARINE...
MALL CRAFT ADVISORY IN EFFECT FOR ENTIRE LAKES WITH WEST WINDS OF
15 TO 25 KNOTS. EXPECT WINDS ON WESTERN BASIN TO DIMINISH TO 15 TO
20 KNOTS BY MID MORNING...SO ONLY RAN SMALL CRAFT THERE UNTIL 10
AM. EXPECT SMALL CRAFT TO BE NEEDED IN THE EAST UNTIL LATE THIS
EVENING. HIGH PRESSURE MOVES QUICKLY ACROSS THE LAKE TONIGHT
SETTING UP FOR THE NEXT SYSTEM THIS WEEKEND. MODELS IN GOOD
AGREEMENT LIFTING ANOTHER LOW PRESSURE SYSTEM NE ACROSS THE CENTRAL
LAKES FRIDAY NIGHT...DRAGGING ANOTHER COLD FRONT ACROSS THE LAKE.
MODELS DO DIFFER ON THE EXACT STRENGTH AND TRACK OF THE LOW. WILL
DEFINITELY NEED A SMALL CRAFT ADVISORY AGAIN SATURDAY AND SUNDAY.
CURRENT FORECAST HAS 30 KNOT WINDS...BUT 35 KNOT GALES ARE NOT OUT
OF THE QUESTION. WILL NEED TO CONTINUE TO MONITOR.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR
LEZ145>149.
SMALL CRAFT ADVISORY UNTIL 10 AM EST THIS MORNING FOR
LEZ142>144.
&&
$$
SYNOPSIS...KIELTYKA
NEAR TERM...ADAMS/KIELTYKA
SHORT TERM...KIELTYKA
LONG TERM...DJB
AVIATION...DJB
MARINE...DJB
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
644 AM EST THU MAR 1 2012
.SYNOPSIS...
A RIDGE WILL BUILD INTO THE AREA TODAY AND THEN MOVE EAST TONIGHT
AS A STRONG COLD FRONT MOVES THROUGH FRIDAY EVENING. A TROUGH WILL
MOVE THROUGH THE EASTERN LAKES ON SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
THE COOL AIR CONTINUES TO FLOW INTO THE REGION. THE LAKE AND 850
MB TEMPERATURE DIFFERENCE WILL BE ONLY AROUND 7C. ENOUGH FOR SOME
LIGHT RAIN OR SNOW SHOWERS...WITH THE 850 TEMPERATURE AND
THICKNESS ON THE EDGE WILL FORECAST A MIX. BACKED DOWN ON THE POPS
IN THE SNOW BELT BASED ON THE RADAR AND THE HRRR MODEL. ADDED
CHANCE OF SPRINKLES TO THE FLURRIES OVER NORTHWEST OHIO BASED ON
WHAT IS GOING ON UPSTREAM. THE CLOUDS ARE STILL TOUGH FOR TODAY.
LOOKING AT THE CLOUDS ATTM THEY SHOULD HANG TOUGH ESPECIALLY OVER
THE NORTHERN COUNTIES. TEMPERATURES WILL NOT RISE THAT MUCH UNLESS
THE CLOUDS THIN SOME. THE BEST CHANCE FOR THAT IS OVER THE
SOUTHERN PORTION OF THE FORECAST AREA.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
THE CLOUDS WILL DECREASE TONIGHT AS THE FLOW BECOMES SOUTH. ON THE
EDGE ABOUT THE TIMING OF THE FRONT FOR FRIDAY EVENING. THE GFS
MOISTURE SEEMS SCANT BUT IT MAY HAVE THE RIGHT IDEA. ALSO IF THE
PRECIPITATION STARTS EARLY IT MAY AFFECT THE HIGHS ON FRIDAY. THE
850 MB TEMPERATURE IS EXPECTED TO BE ABOUT THE SAME AS IT WAS ON
WEDNESDAY WHEN MANY LOCATIONS HAD RECORD HIGHS. SOME RECORD HIGHS
COULD BE APPROACHED ESPECIALLY OVER NORTHWEST AND NORTH CENTRAL
OHIO. THE AREA IS IN A SLIGHT RISK FOR FRIDAY. WILL MENTION THAT
IN THE HWO. WINDS COULD APPROACH WIND ADVISORY CRITERIA BEHIND THE
COLD FRONT FRIDAY NIGHT. THIS WILL ALSO BE MENTIONED IN THE HWO.
SOME LAKE EFFECT SNOW SHOWERS DEVELOP ON SATURDAY AND CONTINUE
INTO SUNDAY. THE SNOW SHOWERS BECOME A LITTLE MORE WIDESPREAD
SUNDAY AS A TROUGH MOVES THROUGH. ON THE EDGE ABOUT THE SNOWFALL
AMOUNTS...IT IS POSSIBLE THAT AN ADVISORY FOR SNOW MAY BE NEEDED
FOR THE SNOW BELT.
&&
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
HIGH A LITTLE SLOWER BUILDING IN ON WEDNESDAY SO KEPT CHANCE POPS
GOING INTO MONDAY. MODELS CONTINUE TO BE IN GOOD AGREEMENT MOVING
HIGH ACROSS THE LOWER LAKES/OHIO VALLEY MONDAY INTO TUESDAY THEN
MOVING THE HIGH OFF THE EAST COAST ON WEDNESDAY. MODELS CONTINUE TO
BRING THE NEXT SYSTEM ACROSS THE AREA ON THURSDAY...BUT GFS
CONTINUES TO BE THE FASTER OF THE 2 MODELS. GFS BRING THE FRONT
INTO THE CENTRAL PART OF THE FORECAST AREA BY 12Z THURSDAY...WHILE
THE ECMWF BRINGS THE FRONT THROUGH DURING THE DAY ON THURSDAY.
LEANED TOWARD THE SLOWER ECMWF FOR THIS FORECAST.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
LOW PRESSURE SYSTEM OVER THE CENTRAL LAKES WITH OVERCAST MVFR CIGS
BACK INTO IOWA. MVFR CIGS THIS MORNING WILL SLOWLY RISE TO VFR FOR
A TIME LATER THIS AFTERNOON.
IN ADDITION...COLD FRONT THROUGH AREA...AS A RESULT WILL HAVE
GUSTY W-SW WINDS UNTIL LATE AFTERNOON. EXPECT WIND GUSTS UP NEAR
30 KNOTS THIS MORNING...WITH WINDS VERY SLOWLY DIMINISHING
THROUGH THE DAY.
OUTLOOK...NON-VFR POSSIBLE FRIDAY EVENING WITH THUNDERSTORMS SOME
MAY BE STRONG TO SEVERE. SCATTERED RAIN SHOWERS SATURDAY. SNOW
RETURNS SUNDAY INTO MONDAY...BEST CHANCE IN THE SNOWBELT EAST OF
CLEVELAND.
&&
.MARINE...
MALL CRAFT ADVISORY IN EFFECT FOR ENTIRE LAKES WITH WEST WINDS OF
15 TO 25 KNOTS. EXPECT WINDS ON WESTERN BASIN TO DIMINISH TO 15 TO
20 KNOTS BY MID MORNING...SO ONLY RAN SMALL CRAFT THERE UNTIL 10
AM. EXPECT SMALL CRAFT TO BE NEEDED IN THE EAST UNTIL LATE THIS
EVENING. HIGH PRESSURE MOVES QUICKLY ACROSS THE LAKE TONIGHT
SETTING UP FOR THE NEXT SYSTEM THIS WEEKEND. MODELS IN GOOD
AGREEMENT LIFTING ANOTHER LOW PRESSURE SYSTEM NE ACROSS THE CENTRAL
LAKES FRIDAY NIGHT...DRAGGING ANOTHER COLD FRONT ACROSS THE LAKE.
MODELS DO DIFFER ON THE EXACT STRENGTH AND TRACK OF THE LOW. WILL
DEFINITELY NEED A SMALL CRAFT ADVISORY AGAIN SATURDAY AND SUNDAY.
CURRENT FORECAST HAS 30 KNOT WINDS...BUT 35 KNOT GALES ARE NOT OUT
OF THE QUESTION. WILL NEED TO CONTINUE TO MONITOR.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...NONE.
PA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR
LEZ145>149.
SMALL CRAFT ADVISORY UNTIL 10 AM EST THIS MORNING FOR
LEZ142>144.
&&
$$
SYNOPSIS...KIELTYKA
NEAR TERM...KIELTYKA
SHORT TERM...KIELTYKA
LONG TERM...DJB
AVIATION...DJB
MARINE...DJB
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
801 PM EST FRI MAR 2 2012
.SYNOPSIS...
STRONG LOW PRESSURE OVER THE MIDWEST HAD A WARM FRONT EXTENDING
EAST INTO THE CAROLINAS AND COLD FRONT TRAILING BACK INTO TEXAS.
THIS LOW WILL DEEPEN AND MOVE RAPIDLY NORTHEAST INTO THE GREAT
LAKES BY SATURDAY MORNING WITH THE COLD FRONT MOVING OFF THE EAST
COAST BY LATE SATURDAY. COOLER HIGH PRESSURE BUILDS IN FOR SUNDAY
THROUGH WEDNESDAY.
&&
.NEAR TERM /THROUGH SATURDAY/...
AS OF 745 PM EST FRIDAY...
UPDATED TO ADJUST LOW TEMPS BASED ON CURRENT COLD READINGS ONGOING
WITHIN THE WEDGE AND TO SPEED UP POPS WITH THE INBOUND CONVECTION
TO THE WEST. STILL IFFY AS TO HOW FAR EAST ANY OF THE STRONGER
CELLS WILL MAKE IT GIVEN SUCH DIFFERENCES IN STABILITY/THETA-E ACROSS
THE WESTERN SLOPES. HOWEVER LOOKS LIKE DYNAMICS AND WIND FIELDS
ALOFT MAY BE ENOUGH TO PUSH SOME OF THESE CELLS INTO THE FAR
WESTERN ZONES BEFORE THEY FADE OR BECOME ELEVATED SO KEEPING
STRONG WIND MENTION THERE AS WELL AS THE GOING FLASH FLOOD WATCH.
LATEST HRRR ALSO A BIT FASTER IN BRINGING THE INITIAL BAND OF
CONVECTION INTO THE FAR NW BY 10-11 PM...THEN SLOWING A BIT OR
REDEVELOPING OVER THE SW ZONES AFTER MIDNIGHT WHERE INSTABILITY
MAY START TO RECOVER AS DEEPENING WARM ADVECTION TO THE SW STARTS
TO WIN OUT. ELSW FEW CHANGES WITH WHATS LEFT OF THE CONVECTIVE
BANDS EXPECTED TO PUSH EAST TOWARD THE BLUE RIDGE AND WEAKEN
BEFORE LIKELY REDEVELOPING IN THE PIEMDONT LATE AS WHATS LEFT OF
THE WEDGE GIVES WAY. EXPECT TEMPS ABOUT AT THEIR LOW POINT ATTM
WITH READINGS LIKELY TO RISE AND PERHAPS QUICKLY AFTER MIDNIGHT AS
THE DEEPER WARMING AHEAD OF THE FRONT ARRIVES.
AS OF 330 PM EST FRIDAY...
DEEPENING SURFACE LOW OVER THE MID-MISSISSIPPI VALLEY EXPECTED TO
TRACK NORTH INTO THE GREAT LAKES TONIGHT WITH TRAILING FRONT TO
DRIVE SOUTHEAST AND ACRS THE CWA LATE TONIGHT. MEANWHILE OVERRUNNING
RAINFALL AND EMBEDDED CONVECTION TO THE NORTH OF THE WARM FRONT
LOCATED ACROSS THE CAROLINAS THIS AFTERNOON WILL CONTINUE
LATE THIS AFTERNOON AND INTO THIS EVENING AS INCREASINGLY MOIST AIR
IS LIFTED NORTHEAST WITH THE STRONG H85 MOISTURE TRANSPORT. PWATS
SOUTH OF THE WARM FRONTAL BOUNDARY QUITE HIGH WITH 1.1 TO 1.3 INCHES
OR UP TO 200 PERCENT OF NORMAL. LOCAL WRF SHOWS THIS SCATTERED
ACTIVITY PERSISTING WELL INTO THE EVENING AND THEN THE MAIN FRONTAL
BOUNDARY ENTERING THE CWA AROUND 05Z IN THE FAR WEST AND EXITING THE
SOUTHEAST CWA AROUND 12Z. NAM A LITTLE SLOWER AND FURTHER SOUTH WITH
HEAVIEST RAINFALL. STILL EXPECT A ROUND OF STRONG TO SEVERE STORMS
ALONG THIS BOUNDARY WITH STRONG SHEAR EXPECTED TO BE IN PLACE
ALTHOUGH INSTABILITY WILL BE LESSENING. RAINFALL RATES UP TO 1 TO 2
INCHES AN HOUR ALONG THE FRONT WILL OCCUR IN AREAS THAT HAVE
RECEIVED ALREADY FROM 0.25 TO 0.75 INCHES TODAY...BASICALLY THE AREA
UNDER THE CONTINUING FLASH FLOOD WATCH WHICH THIS MAY BE ENOUGH TO
PRODUCE RUNOFF PROBLEMS.
AFTER FRONT CLEARS TOMORROW MORNING WINDS SHIFT INTO NORTHWEST AND
BECOME GUSTY WITH FAIRLY STRONG COLD AIR ADVECTION. UNDER PARTLY
CLOUDY SKIES H85 TEMPS FALL FROM +10C AROUND 06Z TO -4C IN THE NW BY
15-18Z ALTHOUGH WARMER TO THE SE. SHOULD YIELD HIGHS FROM NEAR 50 NW
TO 60 SE BUT WILL FEEL A COOLER WITH THE WIND.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
AS OF 330 PM EST FRIDAY...
CLIPPER WAVE IN THE BACKSIDE OF THE UPPER TROUGH WILL BE THE MOST
NOTABLE FEATURE OF THIS PERIOD. AT THIS TIME RANGE...MODELS ARE
TYPICALLY TOO DRY WITH THESE SYSTEMS IF H85 TEMPS ARE COLD
ENOUGH...USUALLY AROUND -8C. THIS APPEARS TO BE THE CASE FOR NW
NC...SE WV OR EXTREME SW VA. HARD TO PINPOINT THE CLIPPER`S TRACK AS
IT WILL FLUCTUATE NORTH AND SOUTH OVER THE NEXT COUPLE OF DAYS. THE
POTENTIAL EXISTS FOR A 1 TO 4 INCH SNOWFALL BLF/JFZ/GEV/TNB
CORRIDOR...MAYBE AS FAR NORTH AS WYTHEVILLE OR FLOYD COUNTY LATE
SUNDAY NIGHT AND EARLY MONDAY MORNING. OF COURSE WE WILL BE FIGHTING
A WARM GROUND. ALTHOUGH THE PROFILE ISN`T AS COLD...THIS DISTURBANCE
IS TAKING A SIMILAR PATH AND IS A LITTLE WEAKER THAN THE STORM WHICH
DUMPED A SURPRISE SEVERAL INCHES ON FLOYD COUNTY SEVERAL WEEKS AGO.
WITH CONTINUED CAA BEHIND THE WAVE MONDAY TEMPS WILL PROBABLY GO NO
WHERE OR ONLY RISE A FEW DEGREES IN THE MOUNTAINS...SO MAX T WAS
LOWERED.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 207 PM EST THURSDAY...
STRONG RIDGE OF HIGH PRESSURE WILL ANCHOR ITSELF ALONG THE EAST
COAST THROUGH AT LEAST WEDNESDAY...MAY BE THURSDAY. A COLD FRONT
WILL THEN SWEEP ACROSS THE REGION AS EARLY AS THURSDAY AFTERNOON BUT
MORE LIKELY FRIDAY. THE GFS IS QUICK WITH THIS FRONT WHILE HPC/ECMWF
ARE SLOWER WITH THE FRONTAL PASSAGE ON FRIDAY. KEEP POPS AT A CHANCE
WITH LOW CONFIDENCE ON TIMING.
TEMPERATURES WILL BE SEASONAL ON TUESDAY THEN MODERATE ABOVE NORMAL
WEDNESDAY INTO FRIDAY. TEMPERATURES THURSDAY COULD BE 10F-15F ABOVE
NORMAL AND POSSIBLY WARMER ON FRIDAY IF RAIN HOLDS OFF UNTIL THE
AFTERNOON.
&&
.AVIATION /01Z SATURDAY THROUGH WEDNESDAY/...
AS OF 600 PM EST FRIDAY...
CURRENTLY IN A LULL IN PRECIP BETWEEN THE EARLIER EXITING WAVE AND
CONVECTION UPSTREAM AHEAD OF THE FRONT BACK IN KY/TN. THIS HAS
LEFT MOST OF THE REGION IN A COOL WEDGE WITH STRONG WARM ADVECTION
ALOFT OVERTOP TRAPPED MOISTURE RESULTING IN WIDESPREAD MVFR/IFR
CIGS...AND MVFR VSBYS IN FOG ATTM. GIVEN STRONGER PUSH OF WARM
AIR ALOFT THIS EVENING EXPECTING CIGS TO REMAIN LOW WITH IFR OR
EVEN AREAS OF LIFR UNTIL THE WARM AIR BECOMES DEEP ENOUGH TO SCOUR
OUT THE LOWER CIGS...LIKELY WHEN THE NEXT ROUND OF PRE-FRONTAL
CONVECTION ARRIVES LATER THIS EVENING. THUS KEEPING POOR FLYING
CONDITIONS IN CLOUDS/FOG EARLY THIS EVENING WITH A MORE ORGANIZED
AREA OF SHRA/TSRA ARRIVING ACROSS THE FAR NW AROUND 9/10 PM...AND
ALONG THE BLUE RIDGE AFTER MIDNIGHT...THEN EASTERN SECTIONS DURING
THE EARLY MORNING HOURS. WINDS ALOFT WILL REMAIN VERY STRONG
RESULTING IN CONTINUED LLWS FOR MOST SPOTS UNTIL BETTER MIXING
ARRIVES WITH THE CONVECTION BY MORNING.
ACTUAL COLD FRONT LOOKS TO PUSH THROUGH MOST OF THE REGION BETWEEN
1 AM AND DAYBREAK...WITH A WIND SHIFT TO THE NORTHWEST DURING THE
LATE NIGHT HOURS. WINDS WILL BE STRONG AND GUSTY BEHIND THE FRONT
BUT CEILINGS SHOULD BE LIFTING AFTER DAYBREAK ON SATURDAY. STRONG
MIXING BEHIND THE FRONT SHOULD COMBINE WITH GOOD DRYING TO PROMOTE
A RETURN TO VFR ALL AREAS AFTER MID MORNING SAT. HOWEVER SURFACE
WINDS SHOULD REMAIN STRONG WITH GUSTS TO 30 KTS OR MORE ESPCLY
KBLF TO KROA SAT AFTERNOON.
ANOTHER SHORT WAVE BRINGS A SECONDARY FRONT AND COLDER AIR IN FOR
SUNDAY NIGHT INTO EARLY MONDAY. EXPECT MOUNTAIN RAIN AND SNOW
SHOWERS WITH MVFR CEILINGS...ESPECIALLY AT BLF AND LWB SUNDAY
THROUGH MONDAY. HIGH PRESSURE WITH DRIER AIR AND VFR CONDITIONS
BUILDS IN FOR TUESDAY/WEDNESDAY.
&&
.HYDROLOGY...
HPC HAS MAINTAINED SLIGHT RISK OF EXCESSIVE RAINFALL ALONG OUR
ABOUT OUR WESTERN CWA BORDER WITH RAINFALL RATES OF 1 TO 1.5
INCHES PER HOUR POSSIBLE IN THE OVERNIGHT STORMS. FLASH FLOOD
WATCH REMAINS IN EFFECT FOR WESTERN COUNTIES WHICH IS ALSO WHERE
HEAVIER RAIN FELL EARLIER THIS WEEK. TOTAL QPF NOT EXPECTED TO BE
BE TOO HIGH...GENERALLY LESS THAN 1 INCH BUT WITH HIGH RATE
RAINFALL IN EMBEDDED THUNDERSTORMS LATER TODAY AND TONIGHT COULD
SEE RAPID RUNOFF IN SOME AREA. SMALL STREAMS MAY RESPOND RAPIDLY
IN THE WATCH AREA.
LARGER RIVERS ARE NEARING CREST NOW ON THE MIDDLE JAMES AND
FALLING RAPIDLY ON THE GREENBRIER AND UPPER JAMES. FORECAST
RAINFALL NOT EXPECTED TO BRING RIVERS BACK TO FLOOD STAGE BUT MAY
PROLONG RECESSION BY 12 TO 24 HOURS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...FLASH FLOOD WATCH UNTIL 6 AM EST SATURDAY FOR VAZ007-019-020.
NC...NONE.
WV...FLASH FLOOD WATCH UNTIL 6 AM EST SATURDAY FOR WVZ042>045.
&&
$$
SYNOPSIS...PC
NEAR TERM...JH/PC
SHORT TERM...RCS
LONG TERM...KM
AVIATION...JH/PC/WERT
HYDROLOGY...
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
347 PM CST THU MAR 1 2012
.SHORT TERM...TONIGHT THROUGH SUNDAY
312 PM CST THU MAR 1 2012
AT 3 PM...THE WATER VAPOR IMAGERY AND PROFILER NETWORKS SHOW THAT
A SHORT WAVE TROUGH WAS MOVING ACROSS SOUTHWEST MINNESOTA AND
WESTERN IOWA. THE RUC SOUNDINGS CONTINUE TO SHOW THAT MUCH OF THE
SYNOPTIC AND ISENTROPIC LIFT ASSOCIATED WITH THIS WAVE GOES TO
SATURATION. THIS IS LIKELY THE REASON WHY THE RADARS ARE
INDICATING SOME ECHOS ACROSS SOUTH CENTRAL MINNESOTA AND NORTHEAST
IOWA. HOWEVER WITH THE AIR MASS DRY IN THE LOW LEVELS...NOT SEEING
ANYTHING REACHING THE GROUND. THIS WAVE WILL MOVE THROUGH SOUTHERN
WISCONSIN THIS EVENING...SO JUST LEFT A 20 PERCENT CHANCE OF
PRECIPITATION TO COVER THIS SYSTEM. FURTHER TO THE NORTHWEST...
ANOTHER SHORT WAVE TROUGH WAS MOVING THROUGH EASTERN NORTH DAKOTA.
THIS SYSTEM LOOKS TO BE TOO FAR NORTH AND WEST TO PRODUCE ANY
PRECIPITATION ACROSS EITHER SOUTHEAST MINNESOTA OR NORTH-CENTRAL
WISCONSIN. AS A RESULT...LOWERED THE PRECIPITATION CHANCES FOR
TONIGHT IN THESE AREAS. MEANWHILE BETWEEN THESE TWO SYSTEM WILL
LIKELY NOT SEE ANY PRECIPITATION...SO TOOK OUT THE PRECIPITATION
CHANCES OUT FOR THESE AREAS.
ON FRIDAY...THE 01.12Z MODELS ARE MUCH CLOSER TO COMING UP WITH A
CONSENSUS FORECAST. THE NAM/WRF HAS KEPT ITS IDEA THAT THERE WOULD
BE SOME PHASING BETWEEN THE NORTHERN AND SOUTHERN STREAMS...THUS...
IT HAS KEPT A STRONGER LOW PRESSURE SYSTEM. WHILE THIS HAS BEEN
CONSISTENT...IT HAS SHIFT THE SURFACE LOW MUCH FURTHER SOUTHEAST
WITH IT TRACKING FROM NORTHERN MISSOURI INTO SOUTHWEST LOWER
MICHIGAN. THIS TRACK IS MORE IN LINE WITH WHAT THE GFS...GEM...
ECMWF...AND UKMET HAVE BEEN SHOWING FOR THE PAST SEVERAL DAYS.
MEANWHILE THE GFS...GEM...ECMWF...AND UKMET ARE NOW SHOWING SOME
PHASING BETWEEN THE NORTHERN AND SOUTHERN STREAMS...SO THEY HAVE A
SIMILAR STRENGTH LOW TO THE NAM/WRF. WHILE THEY MADE THIS
CHANGE...THERE SURFACE LOW TRACK HAS REMAINED RATHER CONSISTENT.
ALL OF THE MODELS ARE SUGGESTING THAT THERE WILL BE STRONG 900 TO
700 MB FRONTOGENESIS ACROSS FAR EASTERN IOWA...NORTHWEST
ILLINOIS...AND SOUTHERN WISCONSIN. ABOVE THIS FRONTOGENESIS...
THERE IS SOME NEGATIVE EPV. AS A RESULT...EXPECTING TO SEE SOME
SLANTWISE CONVECTION TO DEVELOP. THIS INTERSECTS THE -15C OMEGA...SO
THERE WILL BE POSSIBILITY OF 1 TO 2 INCH AN HOUR SNOW RATES. THE
01.15Z SREF DOES SUGGEST THAT THERE WILL BE SOME PROBABILITIES FOR
THIS JUST TO THE EAST OF OUR FORECAST AREA. WITH ALL OF THIS IN
MIND...THINKING THAT THERE WILL BE A BAND OF 2 TO 4 INCHES OF SNOW
EAST OF A DUBUUE IOWA TO WAUTOMA WISCONSIN LINE. IF THESE SNOW
TOTALS STILL LOOK REALISTIC TONIGHT...WE MAY HAVE TO ISSUE A
WINTER WEATHER ADVISORY FOR THIS AREA. ONE CONCERN ABOUT DOING
THIS IS THAT THE TEMPERATURES ARE ABOVE FREEZING AND THEY MAY HAVE
A HARD TIME ACCUMULATING IF THE RATES ARE NOT HIGH ENOUGH.
FROM FRIDAY NIGHT INTO SUNDAY...IT CONTINUES TO LOOK LIKE A LONG
WAVE TROUGH WILL BE LOCATED ACROSS THE REGION. EMBEDDED WEAK SHORT
WAVE TROUGHS IN THIS MAIN WAVE MAY PRODUCE PERIODIC CHANCES FOR
LIGHT SNOW. OVERALL...IF THE SNOW DOES OCCUR...NOT EXPECTING TOO
MUCH ACCUMULATIONS FROM THESE SYSTEMS.
.LONG TERM...SUNDAY NIGHT THROUGH THURSDAY
312 PM CST THU MAR 1 2012
ON TUESDAY...THE MODELS ARE CONTINUING TO INDICATE THAT A 500 MB
HIGH WILL DEVELOP ACROSS THE SOUTHEAST UNITED STATES. SOUTHERLY
WINDS ON THE BACKSIDE OF THIS HIGH WILL BRING WELL ABOVE NORMAL
TEMPERATURES INTO THE FORECASTS AREA. WE MAY SEE TWO TO THREE DAYS
WITH HIGH TEMPERATURES IN THE 50S. THERE MAY BE EVEN A FEW AREAS
THAT SEE TEMPERATURES IN THE 60S. SINCE THE ALL BLEND STILL HAS
SOME COLD SOLUTIONS IN IT...TRENDED THE TEMPERATURES FROM TUESDAY
NIGHT INTO WEDNESDAY TOWARD THE CONSALL INSTEAD OF THE ALL BLEND.
&&
.AVIATION...THROUGH 18Z FRIDAY
1133 AM CST THU MAR 1 2012
MAIN FORECAST CONCERNS IS HOW LONG TO KEEP MVFR CEILING CONDITIONS
AT BOTH KRST AND KLSE TAF SITES AND IF THE LIFR CONDITIONS OVER
WESTERN MINNESOTA AND EASTERN DAKOTAS ADVECT EASTWARD INTO THE TAF
SITES AFTER 06Z FRIDAY. LATEST VISIBLE SATELLITE IMAGERY INDICATE
STRATUS DECK COVERING MUCH OF THE AREA LATE THIS MORNING...WITH
LATEST 17Z METARS REPORTING 1200-2500 FEET CEILINGS ACROSS
SOUTHEAST MINNESOTA AND WESTERN WISCONSIN. FARTHER WEST OVER
WESTERN MINNESOTA AND EASTERN WISCONSIN CEILINGS ARE 200-500 FEET.
THE LATEST 01.12Z NAM/RUC/GFS SHOW MVFR CONDITIONS AT BOTH TAF
SITES THROUGH 22Z THURSDAY...THEN THE LATEST DETERMINISTIC MODELS
ERODE SOME OF THE LOW LEVEL MOISTURE IN ASSOCIATION WITH THE LIFR
CONDITIONS OVER EASTERN DAKOTAS AND WESTERN MINNESOTA...AS THIS
MOISTURE ADVECTS EASTWARD. FOR NOW...WILL CONTINUE WITH MVFR
CONDITIONS AT BOTH KRST AND KLSE TAF SITES THROUGH 22Z AND LEAVE
OUT LIFR CONDITIONS AT BOTH TAF SITES...DUE TO CONFIDENCE LOW OF
OCCURRING AND THE LIFR CONDITIONS SHOULD BE IN SHORT DURATION.
NEXT CONCERN IS LATEST 01.12Z GFS/NAM SHOW SURFACE LOW TRACKING
NORTHEAST INTO THE GREAT LAKES REGION TONIGHT INTO FRIDAY. THIS WILL
ADVECT SOME LOW LEVEL MOISTURE NORTHWARD AND INTO THE AREA. THE
LOW LEVEL MOISTURE WILL MAINLY BE OVER SOUTHERN WISCONSIN AND
EASTERN IOWA. HAVE INTRODUCED MVFR CEILINGS AFTER 07Z FRIDAY AT
KLSE AND AFTER 12Z AT KRST.
&&
.HYDROLOGY...
348 AM CST THU MAR 1 2012
WATER LEVELS IN MOST OF THE TRIBUTARY STREAMS AND RIVERS HAD CRESTED
OR WERE CREATING EARLY THIS MORNING...REMAINING BELOW BANKFULL
STAGE. WITH PRECIP CHANCES TONIGHT/FRI MAINLY FOR SNOW AND COOLER
TEMPS INTO THE WEEKEND...WATER LEVELS IN THE TRIBUTARY STREAMS AND
RIVERS WILL CONTINUE TO FALL. HOWEVER...THE WATER DRAINING OUT OF
THE TRIBUTARIES WILL DRAIN INTO THE MS RIVER. WATER LEVELS ON THE MS
RIVER CAN BE EXPECTED TO RISE A FOOT OR TWO THRU NEXT WEEK AS THIS
WATER FLOWS THROUGH THE SYSTEM. THIS WILL MAKE ANY REMAINING ICE ON
THE MS RIVER BACKWATERS OR POOLS EXTREMELY DANGEROUS TO VENTURE ONTO
OVER THE NEXT FEW DAYS.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
312 PM CST THU MAR 1 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...BOYNE
LONG TERM...BOYNE
AVIATION...DTJ
HYDROLOGY....RRS
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
239 PM CST THU MAR 1 2012
.SHORT TERM...TONIGHT AND FRIDAY.
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW LOW PRESSURE
MOVING OVER THE EASTERN GREAT LAKES...BUT WITH SURFACE TROUGHING
EXTENDING WEST INTO NORTHERN WISCONSIN. THE COMBO OF WEAK CYCLONIC
FLOW AND THERMAL TROUGHING IN THE LOW LEVELS HAS LEAD TO A ROBUST
STRATUS DECK THAT HAS HELD FIRM THROUGH EARLY THIS AFTERNOON. SOME
HOLES IN THE CLOUDS HAVE TRIED TO DEVELOP OVER THE LAKESHORE WITHOUT
MUCH LUCK. MEANWHILE...PLENTY OF INCOMING CONCERNS UPSTREAM.
NORTHERN STREAM SHORTWAVE IS SLOWLY MOVING EAST OVER THE
MONTANA/N.D. BORDER WITH LIGHT SNOW SPREADING ACROSS N.D. FARTHER
SOUTH...WEAK SHORTWAVE IMPULSES ARE MOVING WITHIN FAST SW FLOW OVER
THE CENTRAL PLAINS. ONE DISTURBANCE IS PRODUCING LIGHT SNOW OVER NE
NEBRASKA AND NW IOWA. FINALLY...THE STRONGEST SHORTWAVE IS RAPIDLY
MOVING EAST OVER UTAH/COLORADO...AND SNOW AMOUNTS/HEADLINES WITH
THIS FEATURE WILL BE THE MAIN FORECAST CONCERN.
TONIGHT...NORTHERN STREAM SHORTWAVE WILL MOVE ACROSS NORTH DAKOTA
INTO MINNESOTA AND PUSH AN UPPER LEVEL FRONT INTO NORTHWEST
WISCONSIN LATE TONIGHT. FORCING IS PRETTY WEAK...BUT GUIDANCE IS
OPTIMISTIC ABOUT GENERATING LIGHT SNOW ALONG IT. UPSTREAM OBS SNOW
THE POTENTIAL FOR LIGHT SNOW...SO WILL KEEP IT IN THE FORECAST AFTER
06Z. MEANWHILE...RELATIVELY WEAKER SOUTHERN STREAM IMPULSES WILL
RACE NORTHEAST INTO THE WESTERN GREAT LAKES. LIGHT SNOW OVER NE
NEBRASKA MAY MAKE A RUN AT CENTRAL OR EAST-CENTRAL WISCONSIN LATE AS
WELL. CONFIDENCE NOT QUITE AS HIGH WITH THIS FEATURE AS THE ONE
FARTHER NORTH...SO WILL SHOW LOWER POPS. NOT EXPECTING MUCH ACCUMS
WITH EITHER FEATURE THOUGH...PERHAPS A COUPLE TENTHS.
OTHERWISE...ANTICIPATE THE BACK EDGE OF THE LOW STRATUS WILL
ACCELERATE NORTHEAST OVER THE NORTHERN MISSISSIPPI VALLEY EARLY
TONIGHT. LOW LEVEL WIND FIELDS BECOME WEAK SO THINK THE LOW
OVERCAST WILL HANG AROUND. IF THEY DO CLEAR OVER CENTRAL AND
EAST-CENTRAL WISCONSIN (HIGHEST PROBABILITY)...MID AND HIGH CLOUDS
WILL KEEP THE SKIES OVERCAST. LOWS IN THE MID 20S TO THE LOWER 30S.
FRIDAY...CENTRAL ROCKIES SHORTWAVE WILL BE MOVING ACROSS THE CENTRAL
PLAINS AND NORTHEAST OVER THE MID-MISSISSIPPI VALLEY. IT WILL DRIVE
A RAPIDLY STRENGTHENING SURFACE LOW FROM SW MISSOURI TO NORTHEAST
INDIANA. NUISANT SMALL PRECIP CHANCES WILL LINGER OVER N-C
WISCONSIN AND CENTRAL WISCONSIN IN THE MORNING BUT THE MAIN SHOW
WILL ARRIVE IN THE AFTERNOON AS THE SURFACE LOW MOVES OVER ILLINOIS
AND INDIANA. INCREASING UPPER DIVERGENCE IN THE LEFT FRONT QUAD OF A
JETSTREAK...AND STRONG FGEN CENTERED AROUND 700MB ON THE NW FLANK OF
THE SURFACE LOW WILL LEAD TO PRECIP SPREADING NORTHEAST OVER CENTRAL
AND NORTHEAST WISCONSIN MID-AFTERNOON ONWARD. NEGATIVE EPV ABOVE
THIS FGEN LAYER WILL SUPPORT ENHANCED BANDING ACTIVITY WHICH COULD
LEAD TO LOCALLY HEAVIER SNOWFALL RATES. SOME RAIN MAY MIX IN WITH
THE SNOW OVER THE FOX VALLEY AND LAKESHORE AREAS WHERE TEMPS WILL BE
IN THE MID 30S AS THE PRECIP ARRIVES. BUT ONCE THE HEAVIER PRECIP
RATES MOVE IN...A TIGHTENING BAROCLINIC ZONE WILL LIKELY LEAD TO
RAPIDLY ACCUMULATING SNOW FOR THE EVENING COMMUTE. COULD SEE A
QUICK 1-3 INCHES OF HEAVY SNOW FOR THE FOX VALLEY AND LAKESHORE BY
00Z SATURDAY WITH LESSER AMOUNTS TO THE NORTHWEST. WILL HOIST A
WINTER STORM WATCH STARTING AT 3 PM FOR WINNEBAGO TO SOUTHERN
MARINETTE ON EAST.
.LONG TERM...FRI NGT THRU NXT THU. FAIRLY PROGRESSIVE MEAN FLOW
ACROSS THE COUNTRY AS ONE LONGWAVE TROF MOVES ACROSS THE ERN CONUS
THIS WEEKEND...TO BE FOLLOWED BY ANOTHER LONGWAVE TROF PUSHING
INTO THE WRN CONUS EARLY NXT WEEK. NE WI TO DEAL WITH INITIAL TROF
INTO THE WEEKEND...HOWEVER UPR RIDGING BETWEEN THE TWO TROFS WL
BRING A GOOD WARM-UP EARLY TO MID-WEEK. THE APPROACH OF A CDFNT
WED/THU WL BRING THE NXT BEST CHC OF SEEING WIDESPREAD PCPN.
MDLS CONT TO CONVERGE ON A STORM TRACK FROM TAKING A DEEPENING SFC
LOW ROUGHLY FROM SW LWR MI NEWD TO EXTREME SE ONTARIO FRI NGT.
ACCUMULATING SNOW WL CONT TO IMPACT PRIMARILY ERN WI WHERE AN ADDL
2 TO 4 INCHES IS PSBL DURING THE EVENING. CONVERSELY...WRN SECTIONS
OF THE FCST AREA (GENERALLY WEST OF HWY 51) WL BE LUCKY TO SEE AN
ADDL INCH OF NEW SNOW. STRONG CYCLONIC FLOW COMBINED WITH A SFC
TROF DROPPING SOUTH INTO WI WL KEEP AT LEAST A CHC OF SNOW SHWRS
ACROSS THE FCST AREA THRU THE OVRNGT PERIOD.
THE WEAK SFC TROF SAGS SWD TOWARD SRN WI ON SAT WITH A WEAKENING
CYCLONIC FLOW HANGING ON OVER THE WRN GREAT LKS. FURTHERMORE...THE
LONGWAVE TROF WL BE MOVING INTO THE REGION WITH SEVERAL EMBEDDED
SHORTWAVES PUSHING THRU WI. FINALLY...MID-LVL LAPSE RATES GET
PRETTY STEEP ADDING INSTABILITY TO THE ATMOSPHERE. ADD ALL THIS UP
AND WE ARE LOOKING AT A DECENT CHC OF SNOW SHWRS THROUGHOUT ALL OF
NE WI. WOULD NOT BE SURPRISED TO SEE A FEW LOCALLY HEAVIER SNOW
BURSTS WITH PERHAPS A QUICK ONE-HALF INCH TO AN INCH OF ACCUMULATION.
MAX TEMPS TO BE COOLER THAN PREV DAYS WITH READINGS TOPPING OUT IN
THE LWR TO MID 30S.
SNOW SHWRS SHOULD BECOME MORE ISOLATED IN NATURE SAT NGT AS THE SFC
TROF PULLS AWAY AND THE LOSS OF DAYTIME HEATING MINIMIZES THE
INSTABILITY. SKIES TO REMAIN MOSTLY CLOUDY THRU THE NGT...HOWEVER
ENUF COOL AIR TO HAVE SETTLED OVER THE REGION TO ALLOW TEMPS TO
DROP INTO THE TEENS NORTH/CENTRAL...NEAR 20 EAST-CENTRAL. THE
LONGWAVE TROF TO STILL BE SITUATED OVER THE GREAT LKS THRU SUNDAY...
THEREBY PROVIDING A MEAN NW FLOW ACROSS WI. A PROMINENT SHORTWAVE
IS FCST TO DIVE SE FROM MN TO NRN IL WITH EVEN A SEMBLENCE OF A WEAK
SFC LOW MOVING SE THRU IA. EXPECT TO SEE SCT SNOW SHWRS OVER MUCH OF
NE WI ON SUNDAY WITH MAX TEMPS ONLY REACHING THE MID 20S NORTH/
AROUND 30 CENTRAL/E-CENTRAL.
ANY SNOW SHWR ACTIVITY SHOULD DIMINISH SUNDAY EVENING AS THE
SHORTWAVE DIVES TOWARD THE OHIO RIVER VALLEY AND INSTABILITY
WEAKENS UPON SUNSET. AS HI PRES BUILDS ACROSS THE MIDWEST LATER
SUNDAY NGT...SKIES WL ATTEMPT TO BECOME PARTLY CLOUDY OVER AT LEAST
CENTRAL WI BRINGING ANOTHER COLD NGT TO THE FCST AREA. THE HI PRES
DRIFTS ACROSS WI ON MON AND WL BE SITUATED JUST TO OUR EAST BY 00Z
TUE. WINDS BACKING S-SW WL START TO TAP WARMER AIR TO OUR WEST...
BUT COOLS START TO THE DAY WL ONLY BRING MAX TEMPS ON MON INTO THE
30-35 DEG RANGE. AS THE HI PRES HEADS TOWARD THE ERN CONUS ON TUE...
A STRONG AREA OF LOW PRES WL BE MOVING ACROSS S-CENTRAL CANADA. A
TIGHT PRES GRADIENT TO EXIST ACROSS THE GREAT LKS...BRINGING
BLUSTERY CONDITIONS TO NE WI. THESE GUSTY S-SW WINDS WL ALSO DRAW
VERY MILD AIR INTO WI WITH 8H TEMPS CLIMBING TO NEAR +6C. DEPENDING
ON THE DEPTH OF THE SNOW COVER...MAX TEMPS SHOULD EASILY RISE INTO
THE 40S WITH ANY SNOW-FREE AREAS SURPASSING THE 50 DEG MARK.
THE NXT LONGWAVE TROF TO BE IN THE PROCESS OF PUSHING ACROSS THE
ROCKIES TUE NGT BEFORE REACHING THE NRN/CNTRL PLAINS ON WED.
PRECEDING THIS UPR TROF WL BE A CDFNT WHICH THE MDLS HAVE SOME
TIMING ISSUES WITH. LATEST TRENDS HAVE THIS FNT APPROACHING CENTRAL
WI BY WED AFTERNOON...THUS A NEED FOR CHC POPS ACROSS MOST OF NE
WI. ANOTHER MILD DAY WOULD HAVE ANY PCPN FALL AS RAIN WITH MAX
TEMPS TO RANGE FROM THE MID 40S NORTH TO AROUND 50 DEGS CENTRAL
AND EAST-CENTRAL WI. THE CDFNT DRIVES THRU MOST OF WI WED NGT WITH
A BAND OF LIGHT RAIN MIXING WITH AND CHANGING TO LIGHT SNOW AS
COOLER AIR ARRIVES BEHIND THE FNT. SOME DEBATE LINGERS AS TO
WHETHER THIS FNT WL BE ABLE TO CLEAR THE AREA BEFORE ANY SFC WAVES
CAN DEVELOP ON THE FNT TO SLOW ITS PROGRESS. HAVE USED A GENERAL
CONSENSUS FOR THU WHICH KEEPS THINGS DRY FOR NOW...BUT THU MAY
NEED TO BE RE-EVALUATED LATER AS THE 12Z ECMWF NOW DIGS AN UPR
TROF INTO THE CNTRL CONUS AND REVS UP A SFC LOW TOWARD CHICAGO.
&&
.AVIATION...CYCLONIC FLOW ACROSS MUCH OF THE GREAT LAKES REGION
KEEPING THE LOW STRATUS SOCKED IN AT THE TAF SITES. NOT MUCH
IMPROVEMENT EXPECTED THIS AFTERNOON WITH DAYTIME HEATING. COOLING
TONIGHT SHOULD LEAD TO LOWERING OF CIGS TO IFR LEVELS AT ALL TAF
SITES...WHICH COMPARES WELL TO THE MET GUIDANCE. MAY SEE EVEN LOWER
CIGS OVER CENTRAL AND NORTH-CENTRAL WISCONSIN AS A SURFACE TROUGH
APPROACHES LATE TONIGHT. A SMALL CHANCE OF LIGHT SNOW WITH THIS
TROUGH LATE TONIGHT INTO TOMORROW MORNING. CIGS IMPROVE LATE
TOMORROW MORNING BACK TO MVFR BUT THEN WILL BE WATCHING FOR A
SIGNIFICANT WINTER STORM TO ARRIVE BY LATE AFTERNOON OVER THE FOX
VALLEY AND LAKE SHORE.
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
WINTER STORM WATCH FROM FRIDAY AFTERNOON THROUGH LATE FRIDAY
NIGHT FOR WIZ022-038>040-048>050-073-074.
&&
$$
MPC/AK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1121 PM CST WED FEB 29 2012
.SHORT TERM...
647 PM CST WED FEB 29 2012
MUCH OF THE PRECIPITATION THAT OCCURRED THIS AFTERNOON HAS EITHER
DIMINISHED OR SHIFTED OFF TO THE EAST. THE EASTWARD SHIFT IS A
RESULT OF THE UPPER LOW NOW OVER EAST CENTRAL WISCONSIN PER 00Z
WATER VAPOR LOOP AND RUC ANALYSIS. THE REST OF THE DIMINISHING
PRECIPITATION IS MOST LIKELY DUE TO A COMBINATION OF THE ENTIRE
SYSTEM FILLING...AS WELL AS THE LOSS OF DAYTIME HEATING REDUCING
INSTABILITY FROM THE COLD AIR CORE WITH THE UPPER LOW. STILL
CANNOT RULE OUT A LITTLE DRIZZLE OR LIGHT SNOW MAINLY SOUTH OF
I-90 WHERE A DEFORMATION ZONE IS DISSIPATING...BUT ONLY KEPT
PRECIPITATION CHANCES THERE AT 20 PERCENT. IT IS ENTIRELY POSSIBLE
NOTHING HAPPENS. ALSO...HAVE EXPERIENCED SOME FOG UP AT OUR OFFICE
ON THE LA CROSSE RIDGE. THIS FOG APPEARS TO HAVE FORMED FROM
LINGERING LOW LEVEL MOISTURE AND LIGHT WINDS. WITH THE SURFACE LOW
NEAR WISCONSIN DELLS AND SHIFTING EAST...A NORTHWEST BREEZE WILL
PICK UP. THIS BREEZE SHOULD HELP TO IMPROVE VISIBILITIES ON RIDGE
TOPS WITHIN THE NEXT FEW HOURS. ADDED THIS FOG MENTION TO THE
FORECAST.
HAVE LET ALL HAZARDS EXPIRE AS SCHEDULED FOR 6 PM. NEXT FOCUS FOR
PRECIPITATION WILL BE ON THURSDAY NIGHT INTO FRIDAY. SEE PREVIOUS
SHORT TERM DISCUSSION FOR MORE DETAILS.
.LONG TERM...SUNDAY THROUGH TUESDAY
353 PM CST WED FEB 29 2012
ON TUESDAY...THE 29.12Z MODELS CONTINUE TO SHOW THAT THERE WILL BE
STRONG WARM AIR ADVECTION AHEAD OF THE SYSTEM MOVING OUT OF THE
NORTHERN PLAINS. BOTH THE ECMWF ARE SUGGESTING THAT TEMPERATURES
ALONG AND SOUTH OF THE INTERSTATE 90 CORRIDOR WILL CLIMB INTO THE
50S. WHILE THESE TEMPERATURES LOOK REASONABLE...THERE IS SOME
CONCERN ON HOW WARM TEMPERATURES WILL GET ACROSS THE AREAS WHICH
RECEIVED THE DEEP SNOW PACK LAST NIGHT. THE ALL BLEND AND CONS
BLEND WOULD SUGGEST TEMPERATURES IN THE UPPER 40S. HOWEVER THIS
LOOKS TO BE TOO WARM WITH MUCH SNOW ON THE GROUND...SO COOLED THE
TEMPERATURES DOWN INTO THE LOWER AND MID 40S.
&&
.AVIATION...THROUGH 06Z FRIDAY
1121 PM CST WED FEB 29 2012
STRATUS PERSISTS ACROSS THE UPPER MISSISSIPPI RIVER VALLEY REGION
IN THE WAKE OF A LOW PRESSURE SYSTEM HEADING EAST THROUGH THE
GREAT LAKES. CEILINGS HAVE FALLEN TO LIFR/IFR AT KRST...AIDED BY
NIGHTTIME COOLING. MEANWHILE AT KLSE...A PATCH OF CLEARER SKIES
MOVED THROUGH...TEMPORARILY SCATTERING THE MVFR CLOUDS OUT. THE
MVFR CEILINGS HAVE SINCE MOVED BACK IN. ANTICIPATING THAT THE
STRATUS WILL HOLD THROUGH MUCH OF THE MORNING WITH PERHAPS SOME
SLIGHT RISE AS DRIER AIR OVER CENTRAL MINNESOTA WORKS IN.
VISIBILITIES THROUGHOUT THE MORNING ANTICIPATING TO HOLD AT
VFR...THOUGH IT IS POSSIBLE KRST DROPS BRIEFLY DOWN TO MVFR PRIOR
TO 09Z. BETTER CHANCE FOR CEILINGS TO RISE COMES DURING THE
AFTERNOON HOURS WITH DAYTIME HEATING AND A SURFACE RIDGE CURRENTLY
OVER THE DAKOTAS MOVING THROUGH. THERE ARE SIGNS THAT THE MVFR
STRATUS MAY SCATTER OR CLEAR OUT AROUND 00Z IN MODEL DATA. HAVE
FOLLOWED THIS IDEA...BUT AN ALTOSTRATUS DECK SHOULD QUICKLY COME
IN. THIS ALTOSTRATUS IS ASSOCIATED WITH A TROUGH OF LOW PRESSURE
MOVING INTO WESTERN MINNESOTA. SOME LIGHT SNOW MAY BEGIN TO FALL
OUT OF THIS ALTOSTRATUS AROUND 06Z AT KRST...WHICH WILL BE
CONSIDERED IN THE NEXT TAF FORECAST.
&&
.HYDROLOGY...
353 PM CST WED FEB 29 2012
A GOOD DEAL OF PRECIPITATION FELL LAST NIGHT AS THE MAIN SURGE OF
MOIST AIR ARRIVED. MORNING PRECIPITATION REPORTS INDICATE BETWEEN A
HALF-INCH AND THREE-QUARTERS OF AN INCH ACROSS NORTHEAST IOWA AND
SOUTHWEST WISCONSIN. SOME MINOR WITHIN BANK RISES ON TRIBUTARY
CREEKS AND RIVERS HAS OCCURRED.
FROM SOUTHEAST MN INTO CENTRAL AND NORTHERN WI...AMOUNTS WERE HIGHER
WITH WIDESPREAD REPORTS BETWEEN 1 AND 1.5 INCHES. SOME SPOTS SAW
JUST OVER 1.75 INCHES OF WATER. THE HIGHEST AMOUNTS WERE SEEN FROM
THE ZUMBRO AND WHITEWATER WATERSHEDS...INTO THE TREMPEALEAU AND
BLACK RIVER BASINS. SIGNIFICANT RISES ARE OCCURING IN THESE RIVER
SYSTEMS...WITH SOME SPOTS GETTING CLOSE TO BANKFULL AND FLOOD STAGE.
CURRENTLY...THE SYSTEM IS SPINNING OVERHEAD...DROPPING MORE SNOW AND
DRIZZLE. THIS SHOULD NOT AMOUNT TO A GREAT DEAL MORE WATER CONTENT.
SO THE FEELING IS WE WILL SEE THE MAJORITY OF RIVERS PEAK AND FALL
TONIGHT...IF THEY HAVE NOT ALREADY DONE SO.
THIS RAINFALL ON THE FROZEN SOIL ALSO LED TO WIDESPREAD PONDING OF
WATER...AS IT COULD NOT SOAK IN.
THE STORM DROPPED OVER 15 INCHES OF SNOW ACROSS THE UPPER BLACK
RIVER BASIN...SO AS THIS MELTS...EXPECT THE BLACK TO CONTINUE
RUNNING HIGHER THAN NORMAL INTO NEXT WEEK.
WE ARE ALSO MONITORING THE NEXT STORM SYSTEM FOR THE END OF THE
WEEK. ANY ADDITIONAL WATER COULD LEAD TO RENEWED RISES.
&&
.ARX WATCHES/WARNINGS/ADVISORIES...
647 PM CST WED FEB 29 2012
WI...NONE.
MN...NONE.
IA...NONE.
&&
$$
SHORT TERM...AJ
LONG TERM...BOYNE
AVIATION...AJ
HYDROLOGY...WELVAERT
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1039 PM CST WED FEB 29 2012
UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE
.SHORT TERM...TONIGHT AND THURSDAY.
LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW OCCLUDED LOW
PRESSURE NOW ENTERING SOUTHWEST WISCONSIN THIS AFTERNOON.
PRECIPITATION WITH THIS MAIN CIRCULATION HAS BEEN BLOSSOMING ACROSS
CENTRAL AND NORTHEAST WISCONSIN THIS AFTERNOON...WITH VSBYS DROPPING
TO 3/4SM IN LIGHT SNOW FROM WISCONSIN RAPIDS TO WAUSAU.
TEMPERATURES AND DEWPOINTS HAVE WARMED INTO THE MIDDLE AND UPPER 30S
OVER THE FOX VALLEY...BAYSHORE...AND LAKESHORE...WHERE PRECIP HAS
BEEN MAINLY RAIN AND DRIZZLE THIS AFTERNOON. AS THE LOW TRACKS
ACROSS CENTRAL WISCONSIN THIS EVENING...PRECIP TYPE AND
ACCUMULATIONS ARE THE MAIN FORECAST CONCERNS.
TONIGHT...OCCLUDED LOW PRESSURE WILL MOVE ENE ACROSS CENTRAL
WISCONSIN THIS EVENING. WILL NO LONGER BE FEELING THE EFFECTS OF
THE WARM CONVEYOR BELT...BUT MOISTURE WRAPPING ALL THE WAY AROUND
INTO THE COMMA HEAD WILL LEAD TO WIDESPREAD PRECIPITATION CONTINUING
FOR MUCH OF THE EVENING. THE HEAVIEST PRECIP SHOULD FALL WITHIN AND
ON THE NORTHERN FLANK OF THE CIRCULATION CENTER WHICH SHOULD RUN
FROM ABOUT MARSHFIELD TO DOOR COUNTY. BECAUSE COLDER AIR TO -6C AT
850MB WILL FILTER ACROSS NORTHEAST WISCONSIN...PRECIPITATION TYPE
WILL CHANGE TO ALL SNOW...EVEN NEXT TO THE LAKESHORE. AN ADDITIONAL
INCH OR TWO OF SNOW WILL BE POSSIBLE NORTHWEST OF THE FOX VALLEY AND
BAY SHORE AND OVER THE HIGHER TERRAIN THROUGH THIS EVENING WHERE
TEMPERATURES WILL FALL INTO THE 31-34 DEGREE RANGE. ABOVE FREEZING
TEMPERATURES WILL INITIALLY LIMIT ACCUMS OVER EAST-CENTRAL AND FAR
NORTHEAST WISCONSIN...BUT THOSE LOCATIONS COULD STILL SEE A HALF
INCH TO AN INCH AS TEMPS FALL THIS EVENING. BECAUSE OF THE
POSSIBILITY OF ANOTHER COUPLE INCHES OF SNOW WHICH COULD LEAD TO
RENEWED TRAVEL WOES...WILL LEAVE WINTER WEATHER HEADLINES ALONE.
SNOW WILL BE PUSHING ON TO THE EAST BY LATE IN THE EVENING LEAVING
CLOUDY SKIES PREVAILING ACROSS THE REGION. PLENTY OF FLURRY
ACTIVITY EXISTING ALL THE WAY TO WESTERN MINNESOTA...SO WILL HAVE TO
LEAVE A MENTION THROUGH THE REST OF THE NIGHT. LOW TEMPS RANGING
FROM THE MID 20S WEST TO AROUND 30 EAST.
THURSDAY...LOW PRESSURE WILL CONTINUE EAST TO THE EASTERN GREAT
LAKES. CYCLONIC FLOW WILL HANG AROUND FOR MUCH OF THE MORNING...SO
FIGURE SKY CONDITIONS WILL REMAIN CLOUDY. SOME BREAKS IN THE CLOUDS
ARE LIKELY IN THE AFTERNOON WHEN THE LOW LEVEL MOISTURE THINS OUT
AND THE FLOW BECOMES LIGHT AND WESTERLY. HIGHS IN THE MID 30S TO
AROUND 40F.
.LONG TERM...THU NGT THRU NXT WED. MDLS HAVE COME INTO BETTER
AGREEMENT WITH REGARDS TO A BROAD LONGWAVE TROF PUSHING ACROSS THE
CONUS DURING THE FIRST HALF OF THE EXTENDED PERIOD. STILL WATCHING
A SYSTEM PRECEDING THIS TROF WHICH COULD BRING A MIX OF PCPN TYPES
TO NE WI ON FRI. MEAN FLOW TENDS TO FLATTEN BY EARLY NXT WEEK
ALLOWING FOR MILD PACIFIC AIR TO RUSH ACROSS THE CONUS. DEPENDING
ON THE AMOUNT OF SNOW STILL ON THE GROUND...SOME PARTS OF CNTRL/
E-CNTRL WI COULD PUSH THE 50 DEG MARK BY TUE BEFORE THE NXT CDFNT
ARRIVES WITH THE NXT CHC OF PCPN.
THE LONGWAVE TROF MOVES THRU THE ROCKIES THU NGT AND ENTERS THE
PLAINS TOWARD DAYBREAK. AS THIS OCCURS...A SFC LOW IS FCST TO DVLP
OVER THE CNTRL/SRN PLAINS AND MOVE NE TOWARD THE OZARKS/MO VALLEY
AREA. WAA TO OVERSPREAD WI WITH ENUF MSTR EVIDENT TO BRING PCPN
INTO PARTS OF THE FCST AFTER MIDNGT. TEMPS WOULD BE COLD ENUF SUCH
THAT ANY PCPN WOULD BE SNOW...BUT ANY ACCUMULATIONS WOULD BE VERY
MINOR.
QSTNS REMAIN AS TO THE EXACT TRACK OF THE SFC LOW AS IT HEADS NE
TOWARD SRN SECTIONS OF THE GREAT LKS ON FRI. THE NAM REMAINS A
WESTWARD TRACK OUTLIER PRIMARILY DUE TO TRYING TO PHASE A NRN
PIECE OF SHORTWAVE TROF WITH THE SFC LOW. THE GEM MODEL TRACKS THE
SFC LOW NEWD INTO SW/CNTRL SECTIONS OF LWR MI...WHILE THE GFS/UKMET/
ECMWF NOW ALL PREFER A MORE ERN ROUTE AND TAKE THE LOW PRES TOWARD
NE INDIANA/SE LWR MI. SINCE THIS SYSTEM IS JUST COMING ASHORE TODAY
(WED)...TRACK WL LIKELY WAFFLE A BIT MORE BEFORE SETTLING DOWN...
THUS HAVE LEANED TOWARD THE MORE CONSISTENT GFS/UKMET/ECMWF WHICH
WOULD BRING AN INCH OR TWO OF ACCUMULATION TO NE WI. HAVE RAISED
POPS TO LIKELY FOR ALMOST THE ENTIRE FCST AERA AND GONE MORE SNOW
THAN RAIN FOR ERN WI.
SNOW CHCS TO CONT THRU AT LEAST FRI EVENING BEFORE TAPERING OFF
FROM SOUTH TO NORTH AS THE SFC LOW MOVES INTO SE ONTARIO. COULD
SEE AN ADDL INCH OR TWO OF ACCUMULATION...MAINLY ACROSS THE NRN
WI. SYSTEM CONTS TO LIFT NE TOWARD THE CANADIAN MARITIMES ON SAT
WITH A TRAILING SHORTWAVE TROF/EMBEDDED SHORTWAVES STILL MOVING
THRU WI. WL NEED TO CARRY SOME SNOW SHWR ACTIVITY THRU THE DAY
WITH THE BETTER CHCS ACROSS THE NORTH AS WINDS TURN W-NW WITH SOME
PSBL LK ENHANCEMENT. TEMPS TO CONT A DOWNWARD TREND WITH HI TEMPS
GENERALLY IN THE 30-35 DEG RANGE.
THE LONGWAVE TROF IS THEN EXPECTED TO MVOE THRU THE RGN SAT NGT
INTO SUNDAY WITH VARIOUS PIECES OF SHORTWAVE ENERGY DROPPING SE IN
THE NW FLOW ALOFT. NE WI ALSO RESIDE UNDER THE FAVORABLE LEFT EXIT
RGN OF THE UPR JET FOR ADDED LIFT. EXPECT TO SEE AT LEAST ISOLATED
SNOW SHWRS ACROSS THE FCST AREA BOTH SAT NGT AND SUNDAY WITH A
MINOR ACCUMULATION PSBL WHERE ANY SNOW SHWRS BECOME MORE PRONOUNCED.
SUNDAY ALSO LOOKS TO BE THE COLDEST DAY OF THE EXTENDED FCST WITH
MAX TEMPS MAINLY IN THE 25-30 DEG RANGE. A WEAK AREA OF HI PRES IS
THEN FCST TO BUILD ACROSS THE WRN GREAT LKS RGN SUNDAY NGT AND
RESIDE TO OUR EAST ON MON. ANY LINGERING SNOW SHWRS SHOULD END
RATHER QUICKLY WITH WINDS BACKING TO THE S-SW BY MON ON THE
BACKSIDE OF THE HI PRES. COOL START TO MON WL LIMIT AMOUNT OF
DIURNAL WARMING EVEN AS A SURGE OF WARMER AIR ALOFT PUSHES INTO
THE STATE.
INCREASING S-SW WINDS MON NGT WL SEND A WRMFNT NWD WITH MUCH
MILDER AIR STREAMING INTO NE WI. A NEW...BROAD UPR TROF IS PROGGED
TO MOVE INTO THE CNTRL CONUS ON TUE AND HELP PUSH A CDFNT ACROSS
THE UPR MIDWEST. MOST OF THE FORCING/LIFT APRS TO BE BEHIND THE
FNT...THUS HAVE KEPT TUE DRY AND MILD WITH MAX TEMPS SURPASSING
THE 40 DEG MARK. IF CLOUDS CAN STAY AWAY LONG ENUF...PARTS OF
CNTRL/E-CNTRL WI COULD REACH 50 DEGS. THE CDFNT PUSHES THRU WI TUE
NGT AND THEN THE MDLS DVLP SEVERAL WAVES ALONG THE FNT WHICH WOULD
HELP FOCUS PCPN ACROSS THE FCST AREA ON WED. BASED ON PROJECTED
LOCATION OF THE CDFNT AND SFC WAVES...HAVE GONE WITH A HI CHC POP
FOR THE VAST MAJORITY OF NE WI. ANOTHER PBLM WL BE PCPN TYPE AS
COOLER AIR TO SETTLE OVER THE NW HALF OF WI. HAVE GONE WITH A
RAIN/SNOW MIX FOR N-CNTRL WI...BUT KEPT PCPN AS ALL RAIN IN THE
CENTRAL AND EAST.
&&
.AVIATION...MVFR CIGS OF 1500 TO 3000 FT AGL ACROSS MOST OF THE
AREA OVERNIGHT AND PERHAPS A FEW SNOW FLURRIES.
RDM
&&
.GRB WATCHES/WARNINGS/ADVISORIES...
NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS TAUNTON MA
145 AM EST SAT MAR 3 2012
.SYNOPSIS...
STRONG LOW PRESSURE MOVES THROUGH THE GREAT LAKES TONIGHT. THIS
WILL PUSH MILDER AIR INTO NEW ENGLAND OVERNIGHT AND SATURDAY
MORNING. THE LOW THEN SWINGS A COLD FRONT THROUGH NEW ENGLAND
AROUND MIDDAY SATURDAY. LOW PRES OVER THE MARITIMES PROVIDES
MAINLY DRY AND COLDER WEATHER SUN AND MON...THEN HIGH PRES MOVES
OFFSHORE YIELDING A SIGNIFICANT WARMING TREND MID TO LATE NEXT
WEEK.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
130 AM UPDATE...ADJUSTED TEMPERATURE TRENDS TO REFLECT LATEST
OBSERVATIONS. INITIAL BAND OF OVERRUNNING PRECIPITATION ALREADY
MOVING TOWARD THE COAST AND NORTHERN NEW ENGLAND. LOTS OF REPORTS
OF SLEET AND SNOW...WITH QUICK ACCUMULATIONS UP TO 1 INCH. SOME
FREEZING RAIN REPORTED IN THE LOWER CT RIVER VALLEY IN MA. FARTHER
SOUTH IN CT...AL PRECIPITATION CHANGED TO RAIN. WILL PROBABLY
CANCEL THE WINTER WEATHER ADVISORY ACROSS NORTHERN CT AT THE TOP
OF THE HOUR TO BE SURE THE WARM AIR STAYS PUT.
PREVIOUS DISCUSSION...
HAVE EXTENDED THE WINTER WEATHER ADVISORY ALONG THE
EDGES A BIT TO INCLUDE INTERIOR ESSEX COUNTY IN NE MA...NW
PROVIDENCE COUNTY AND THE NORTHERN CT COUNTIES OF
HARTFORD...TOLLAND AND WINDHAM. WE BELIEVE THE RISK OF A FEW HOURS
OF MIXED PRECIPITATION IS SUFFICIENT TO WARRANT THE ADVISORY
EXPANSION BASED ON CURRENT OBS AND LATEST MODEL PROJECTIONS. FOR
INTERIOR ESSEX COUNTY...SHORT TERM MODELS CONSISTENT IN KEEPING 2M
TEMPS AT OR BELOW FREEZING FOR A FEW HOURS AFTER LIGHT
PRECIPITATION MOVES IN. FOR NORTHERN CT AND NW RI...CONFIDENCE IS
LOWER BUT HERE TOO TEMP/DEWPT READINGS AND SHORT TERM MODEL
PROJECTIONS...INCLUDING RUC AND HRRR...POINT TO 2 TO 3 HOURS OF
LIGHT SNOW/SLEET/FREEZING RAIN. WHEN IT COMES TO SLEET AND
FREEZING RAIN...VERY SMALL AMOUNTS WILL CAUSE UNTREATED SURFACES
TO QUICKLY BECOME VERY SLIPPERY. RADAR AND BUFKIT PROFILES SUGGEST
A RISK OF A SEEDER-FEEDER MECHANISM SETTING UP LATER THIS
EVENING...SOONER THAN LATER FOR NORTHERN CT AND NW RI. THUS...
OPTED TO START THE ADVISORY AT 9 PM FOR THIS AREA.
INTERESTINGLY...A SMALL MESOSCALE AREA OF PATCHY VERY LIGHT SNOW
HAS ALREADY BROKEN OUT ALONG THE CT RIVER VALLEY...POSSIBLY A
COMBINATION OF TERRAIN INDUCED CONVERGENCE AND THE BEGINNING OF
SEEDING FROM ABOVE.
WARM ADVECTION AHEAD OF THE MIDWEST SYSTEM BRINGS INCREASING
ISENTROPIC LIFT OVERNIGHT. THE MAIN AREA OF LIFT ENTERS WESTERN
CT/MA AROUND MIDNIGHT AND IS CENTERED OVER SOUTHERN NEW ENGLAND
AROUND SUNRISE. LIFT RATES REACH A MAXIMUM AROUND 25 MB/HOUR AT
12Z.
PTYPE STARTS MESSY. ECMWF AND GFS SHOW STRONG LOW LEVEL NORTHERLY
AGEOSTROPHIC FLOW AT 06Z...WHICH WOULD HOLD IN COLD AIR NEAR THE
SURFACE. OBSERVED TEMPS ACROSS NORTHERN MASS AND SOUTHERN NH ARE
STARTING BELOW FREEZING. AREAS ALONG THE MASS PIKE AND IN NORTHERN
CT/NW RHODE ISLAND ARE MARGINAL. LOOKS LIKE MOSTLY RAIN IN THE
COASTAL PLAIN...ALTHOUGH BRIEF SLEET POSSIBLE AT THE START. THE
BEST CHANCE OF SNOW/SLEET/FREEZING RAIN WOULD BE IN WESTERN
MASS/WORCESTER HILLS/SOUTHERN NH. AN INCH OR SO OF SNOW IS
POSSIBLE IN THIS AREA AS WELL AS ICE OF UP TO 0.1 INCH.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SUNDAY/...
STRONG LIFT IN THE MORNING DECREASING TOWARD MIDDAY. COLD FRONT
MOVES ACROSS FROM WEST TO EAST LATE MORNING/MIDDAY WITH A WIND
SHIFT TO WEST FOR THE AFTERNOON. THIS WOULD MEAN A WET MORNING
WITH RAIN BECOMING MORE SHOWERY AS THE COLD FRONT APPROACHES.
ELEVATED INSTABILITY WITH TOTALS REACHING 50-55 AND SHOWALTER
REACHING -1. THIS IS ENOUGH TO MENTION A CHANCE OF THUNDER.
INCREASING SOUTH FLOW WORKS TO THE SURFACE AND MOVES NORTH ACROSS
THE REGION. THIS WILL CHANGE ANY LINGERING FREEZING PCPN TO RAIN.
IT WILL ALSO TRANSPORT MILDER TEMPS INTO THE REGION. 950 MB TEMPS
REACH 10C IN THE COASTAL PLAIN AND 4C IN THE NORTHWEST. THIS WOULD
THIS WOULD SUPPORT MAX TEMPS IN THE UPPER 40S AND 50S.
ONCE THE COLD FRONT MOVES THROUGH...WINDS WILL SHIFT TO WEST
DURING THE AFTERNOON AND BRING DRIER AIR TO THE REGION. MODEL TIME
SECTIONS SHOW DRYING AT ALL LEVELS...SO EXPECT AFTERNOON/EVENING
CLEARING...THEN MOSTLY CLEAR AT NIGHT.
A WAVE DEVELOPS ALONG THE DEPARTING COLD FRONT SATURDAY
NIGHT...BUT THE UPPER FLOW FEATURES A PROGRESSIVE TROUGH WITH FLOW
TOWARD THE EAST OVER THE NORTHEAST...SO ANY OFFSHORE LOW SHOULD
STAY OUT TO SEA. ENOUGH INCREASE IN HIGH LEVEL MOISTURE SO THAT WE
COULD GET INCREASED CIRRUS DURING SATURDAY NIGHT.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
HIGHLIGHTS...
* BOTH WINTER AND SPRING-LIKE TEMPS FEATURED THIS PERIOD
* MAINLY DRY WEATHER MUCH OF THE TIME
MODEL PREFERENCES AND SYNOPTIC OVERALL...
12Z MODELS IN VERY GOOD AGREEMENT EARLY THIS PERIOD ON THE LARGE
SCALE FLOW ACROSS THE CONUS WHICH FEATURES A BROAD TROUGH OVER THE
EASTERN STATES AND ASSOCIATED BELOW NORMAL HEIGHTS AND TEMPS. MAINLY
DRY WEATHER SHOULD PREVAIL SUN-MON AS LOW LEVEL BAROCLINIC
ZONE/STORM TRACK SHOULD STAY FAR ENOUGH OFFSHORE. THEN MODELS AGREE
ON EJECTING TROUGH AND ASSOCIATED COLD AIRMASS BEGINNING TUE AS
SUBTROPICAL RIDGE DEVELOPS OVER THE SW ATLC. MODELS THEN DIVERGE
MID TO LATE NEXT WEEK WITH THE GFS ON THE PROGRESSIVE/FAST EDGE OF
THE GUIDANCE WITH THE NEXT UPSTREAM TROUGH. CONVERSELY THE 12Z ECMWF
REMAINS ON THE SLOW SIDE OF THE GUID ENVELOPE WITH THE 12Z GEFS AND
00Z ECENS SOMEWHERE IN BETWEEN. THIS WOULD SUGGEST THE MILD TO WARM
WEATHER DEVELOPING DURING THE MIDDLE OF NEXT WEEK MAY LINGER LONGER
THAN THE 12Z GFS SUGGEST. THUS WE HAVE TRENDED WARMER /CLOSER TO 18Z
HPC GUIDANCE/ AND SLOWER WITH FROPA THAN THE 12Z GMOS FOR NEXT THU
AND FRI.
DAILY SENSIBLE WEATHER DETAILS...
SUN...MID LEVEL TROF MAY BACK SUFFICIENTLY FOR OFFSHORE FRONTAL
BOUNDARY AND SURFACE WAVE TO RETROGRADE ENOUGH FOR PRECIP SHIELD TO
GRAZE CAPE COD AND THE ISLANDS. COLUMN APPEARS COLD ENOUGH TO
SUPPORT SNOW WITH SUB-FREEZING WET BULB TEMPS. HOWEVER GIVEN ONLY
VERY LIGHT PRECIP IS EXPECTED MUCH OF THIS MAY BE VIRGA AND FALL AS
RAIN AS PRECIP INTENSITY WILL LIKELY BE TOO LIGHT FOR WET BULB TEMPS
TO BE REALIZED. ELSEWHERE DRY WEATHER WILL PREVAIL ALONG WITH AT
LEAST PARTIAL SUNSHINE AND SEASONABLE TEMPERATURES.
MON...MORE OF A WINTER-LIKE DAY WITH BELOW NORMAL TEMPS. DIFFICULT
TEMP FORECAST HERE WITH NAM AND GFS MUCH COLDER ALOFT THAN THE
ECMWF. 12Z GMOS OFFERS HIGHS IN THE 30S...WHICH SEEMS REASONABLE.
HOWEVER IF CLOUD COVER BECOMES EXTENSIVE WITH COLD POOL ALOFT AND
CYCLONIC FLOW HIGH TEMPS WILL BE COOLER.
TUE...WILL BE A TRANSITION DAY WITH TEMPS REBOUNDING TOWARD 40 AS
HIGH PRES MOVES SOUTH OF NEW ENGLAND AND RETURN FLOW BEGINS TO
MODIFY COLD AIRMASS OVER THE REGION.
WED...TEMPS CONTINUE TO CLIMB INTO THE 50S COURTESY OF SUBTROPICAL
RIDGE DEVELOPING OFFSHORE.
THU AND FRI...COULD MAKE A RUN AT 60F THU AND POSSIBLE FRI AS STRONG
LOW LEVEL WAA OCCURS AHEAD OF APPROACHING COLD FRONT. AS MENTIONED
ABOVE FAVORED THE 12Z GEFS AND 00Z ECENS AS THIS SERVES AS A GOOD
COMPROMISE BETWEEN THE FAST OP 12Z GFS AND SLOWER 12Z ECMWF.
&&
.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
FORECASTER CONFIDENCE LEVELS...
LOW...LESS THAN 30 PERCENT
MODERATE...30 PERCENT TO 60 PERCENT
HIGH...GREATER THAN 60 PERCENT
THROUGH 12Z...MAINLY MVFR CIGS PERSIST ACROSS SOUTHERN NEW
ENGLAND. IFR CIGS IN THE WORCESTER HILLS AND MONADNOCKS. CURRENTLY
EXPECTING WIDESPREAD IFR TO OVERSPREAD THE REGION FROM THE
SOUTHEAST EARLY THIS MORNING. HIGH CONFIDENCE IN THE TRENDS...WITH
LOWER CONFIDENCE ON THE EXACT TIMING.
TODAY...SHOWERS AND IFR CONTINUE THIS MORNING...ESPECIALLY AS A
LINE OF SHOWERS MOVES ACROSS MID MORNING TO MIDDAY. THERE IS SOME
POTENTIAL FOR SCATTERED THUNDERSTORMS WITH THESE SHOWERS. A COLD
FRONT SWEEPS THROUGH AROUND MIDDAY OR EARLY AFTERNOON WITH A WIND
SHIFT TO WEST. PCPN ENDS AT THAT TIME WITH CONDITIONS IMPROVING
TO VFR FROM WEST TO EAST THIS AFTERNOON. HIGH CONFIDENCE IN
TREND...MODERATE CONFIDENCE ON TIMING.
TONIGHT...HIGH CONFIDENCE VFR. HIGH CLOUDS RETURN OVERNIGHT
ESPECIALLY ALONG THE SOUTH COAST.
SUNDAY...MODERATE TO HIGH CONFIDENCE VFR AS A LOW PRESSURE MOVES
NORTH WELL OFFSHORE.
KBOS TERMINAL...
MVFR CEILINGS THIS EVENING BUT TRENDING TOWARD IFR TOWARD 06Z AS
PRECIP SHIELD OVERSPREADS EASTERN MA. THE PCPN MAY START AS A MIX
OF RAIN/SNOW/SLEET BUT SHOULD QUICKLY CHANGE TO ALL RAIN. IFR/LIFR
CONDITIONS LATE TONIGHT THROUGH SATURDAY MORNING. A LINE OF
SHOWERS MOVES THROUGH AROUND MIDDAY...POSSIBLY ACCOMPANIED BY A
THUNDERSTORM...BUT HIGHER PROBABILITY OF TSTMS WILL BE SOUTH OVER
THE OCEAN. WINDS SHIFT TO WEST...THEN CONDITIONS IMPROVE TO VFR
DURING THE AFTERNOON. VFR SATURDAY NIGHT.
OUTLOOK...SUNDAY NIGHT THROUGH WEDNESDAY...
SUNDAY NIGHT AND MONDAY...MARGINAL MVFR-VFR CIGS WITH LOWEST
CIGS SHIFTING FROM THE CAPE INLAND/HIGHER TERRAIN MON. MAINLY DRY
WEATHER BOTH DAYS. MODERATE TO HIGH CONFIDENCE.
TUESDAY AND WED...
HIGH CONFIDENCE FOR VFR BOTH DAYS AS HIGH PRES BUILDS OVER THE AREA.
DRY WEATHER EXPECTED. SW WINDS MAY BECOME GUSTY WED.
&&
.MARINE...
HIGH PRESSURE MOVES OFF TO THE EAST THIS EVENING BRINGING A
SOUTHEAST FLOW TO THE WATERS. LOW PRESSURE MOVING THROUGH THE
GREAT LAKES WILL BRING STRONG WINDS ALOFT WHICH WILL TRANSPORT
ENOUGH MOISTURE FOR RAIN. THE INCREASED PRESSURE GRADIENT WILL
ALSO SUPPORT SOME INCREASE IN WIND SPEEDS. SO LATER TONIGHT WINDS
WILL REACH 25-30 KNOTS...AND SEAS WILL BUILD WITH THE EXPOSED
WATERS AT 5 FEET OR HIGHER.
SMALL CRAFT ADVISORIES HAVE BEEN EITHER CONTINUED OR ISSUED FOR
ALL WATERS EXCEPT BOSTON HARBOR AND NARRAGANSETT BAY. WINDS FOR
THESE LATTER WATERS DON/T LOOK TO REACH 25 KNOTS...BUT LOW
CONFIDENCE ON THIS PART OF THE FORECAST.
A COLD FRONT SWEEPS ACROSS THE WATERS DURING THE AFTERNOON. WEST
WINDS WILL HOVER NEAR 20-25 KNOTS LATER SATURDAY AND SATURDAY
NIGHT. SEAS WILL PERSIST AT OR ABOVE 5 FEET MUCH OF THIS TIME.
OUTLOOK...SUNDAY THROUGH WEDNESDAY...
SUN...MAINLY DRY WEATHER WITH LOW PRES TRACKING WELL S AND E OF NEW
ENGLAND.
MON...N-NW WINDS MAY BECOME GUSTY MON NIGHT AS LOW PRES TRACKS SE OF
NEW ENGLAND. DRY WEATHER AND GOOD VSBY SHOULD PREVAIL.
TUE...QUIET WEATHER PREVAILS WITH GUSTY NNW WINDS POSSIBLE EARLY TUE
BUT LIKELY DIMINISHING AS HIGH PRES DRIFT INTO THE AREA.
WED...SW WINDS MAY BECOME GUSTY ESPECIALLY NEAR SHORE AS HIGH PRES
DRIFTS SEAWARD. DRY WEATHER AND GOOD VSBY SHOULD PREVAIL.
&&
.CLIMATE...
A PUBLIC INFORMATION STATEMENT WAS ISSUED AT 225 PM. THIS
STATEMENT GIVES A REVIEW OF DECEMBER-JANUARY-FEBRUARY CONDITIONS AT
OUR FOUR CLIMATE SITES...BOSTON-PROVIDENCE-HARTFORD-WORCESTER.
&&
.BOX WATCHES/WARNINGS/ADVISORIES...
CT...WINTER WEATHER ADVISORY UNTIL 4 AM EST EARLY THIS MORNING FOR
CTZ002>004.
MA...WINTER WEATHER ADVISORY UNTIL 5 AM EST EARLY THIS MORNING FOR
MAZ009>012.
WINTER WEATHER ADVISORY UNTIL 7 AM EST THIS MORNING FOR
MAZ002>006-008-026.
NH...WINTER WEATHER ADVISORY UNTIL 9 AM EST THIS MORNING FOR NHZ011-
012-015.
RI...WINTER WEATHER ADVISORY UNTIL 4 AM EST EARLY THIS MORNING FOR
RIZ001.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR
ANZ231>234.
SMALL CRAFT ADVISORY UNTIL 6 AM EST SUNDAY FOR ANZ235-237-250-
254>256.
SMALL CRAFT ADVISORY UNTIL 4 AM EST SUNDAY FOR ANZ251.
&&
$$
SYNOPSIS...WTB/NOCERA
NEAR TERM...BELK
SHORT TERM...WTB
LONG TERM...NOCERA
AVIATION...WTB/NOCERA
MARINE...WTB/NOCERA
CLIMATE...
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1154 PM EST FRI MAR 2 2012
.UPDATE...
ISSUED AT 651 PM EST FRI MAR 2 2012
THE MAIN AREA OF SHOWERS AND THUNDERSTORMS WAS LIFTING NORTH OF
KALAMAZOO AND BATTLE CREEK. WINDS HAVE SHIFTED AT MUSKEGON AND ARE
NOW OUT OF THE NORTH. THIS WILL HELP TO DRAW DOWN THE COLDER AIR
AND RESULT IN A CHANGE OVER TO SNOW IN MUSKEGON BY 9 PM. WINDS
HAVE NOT INCREASED YET...BUT BY 10 PM WE SHOULD BE SEEING THE
POWERFUL GUSTS DEVELOPING ALONG INTERSTATE 94.
&&
.SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT)
ISSUED AT 935 PM EST FRI MAR 2 2012
NO HEADLINE/SIGNIFICANT FCST CHANGES ARE PLANNED THIS EVENING. ONE
TO THREE INCHES OF SNOW HAS ALREADY FALLEN ACROSS OUR NNW FCST AREA
WITH NUMEROUS REPORTS OF HAZARDOUS TRAVEL CONDITIONS UP THERE. THE
986 MB SFC LOW IS NOW CENTERED JUST NNE OF GRR. WINDS WILL RAMP UP
LATE THIS EVENING AND OVERNIGHT AND THE HIGH WIND WARNING REMAINS IN
EFFECT TO COVER THAT THROUGH 12Z SAT.
SFC LOW TO TRACK ACROSS KALAMAZOO TO SAGINAW BAY THIS EVENING
WHILE RAPIDLY DEEPENING. LATEST MSAS SHOWS IT AT PRESENTLY 990MB
IN WRN INDIANA AND THE HRR RUC HAS IT 970MB AT 07Z OVER SAGINAW
BAY. AS THE LOW PASSES BY LATER THIS EVENING LOOK FOR WIND GUSTS
APPROACHING OR EXCEEDING WARNING CRITERIA OF 50 KNOTS. THIS IS
SUPPORTED IN FCST SNDGS AND HRR WIND GUST PROGS... WITH BEST
THREAT OVER THE SRN FCST AREA. NOT AS CERTAIN NORTH OF ST JOHNS.
BEST WINDOW FOR SVR GUSTS IS ROUGHLY 04Z-08Z... BUT WILL HAVE
BUFFER ON EITHER SIDE FOR THE WARNING TIME.
AS FAR AS THE HEAVY SNOW THREAT... DID NOT STRAY TOO MUCH FROM
PREVIOUS FCST. CONVECTION/LIGHTNING STRIKES NOW BEING OBSERVED
ACROSS NRN IL IN THE SRN EDGE OF DEVELOPING DEFORMATION
ZONE/TROWAL. THIS FEATURE WILL ONLY INTENSIFY THIS EVENING... THEN
IT/S JUST A MATTER OF CHANGING PCPN OVER TO SNOW IN THE WARNING
AREA. IT LOOKS PRETTY WARM THROUGH 00Z... THEN RAPID DYNAMICAL
COOLING SHOULD FORCE CHANGEOVER TO HEAVY SNOW WITH ONE TO TWO INCH
PER HOUR RATES STILL LIKELY TONIGHT.
BECAUSE OF THE MARGINAL SFC TEMPS IN THE MID 30S ACROSS THE
WARNING AREA... ELEVATION WILL PROBABLY PLAY A CRITICAL ROLE IN
WHEN RAIN CHANGES TO SNOW AND ALSO IN STORM TOTAL SNOW
ACCUMULATION. HAVE ADDED IN MECOSTA COUNTY INTO THE WARNING AS
HIGHER ELEVATIONS THERE MAY RESULT IN AMOUNTS APPROACHING SIX
INCHES. HOWEVER EVEN WHERE ACCUMS DO NOT REACH SIX INCHES THE
WARNING IS PROBABLY STILL WELL JUSTIFIED DUE TO THE COMBO OF THE
HIGH WINDS AND THE SNOW.
HEAVY SYNOPTIC SNOW IN THE DEFORMATION ZONE SHOULD BE WINDING DOWN
TOWARD 12Z SAT... WITH A TRANSITION TO LAKE EFFECT/ENHANCED SNOWS.
ANOTHER 2 TO 4 INCHES IS POSSIBLE ON SATURDAY IN THE WARNING
AREA... AND ALSO FARTHER SOUTH INCLUDING THE GRR/BIV AREAS. AFTER
THE HIGH WIND WARNING EXPIRES... A WINTER WEATHER ADVISORY MAY BE
NEEDED SATURDAY FOR KENT/OTTAWA SOUTH... WHILE THE WARNING
CONTINUES IN THE NORTH.
.LONG TERM...(SUNDAY THROUGH FRIDAY)
ISSUED AT 213 PM EST FRI MAR 2 2012
THERE ARE TWO SYSTEMS WE ARE WATCHING IN THE LONG TERM PERIOD. THE
FIRST IS THE LAKE ENHANCED SNOW SHOWERS WITH THE ARCTIC FRONT
COMING THROUGH EARLY SUNDAY MORNING THEN THE SYSTEM IN THE
WEDNESDAY TIME FRAME.
THERE IS A TRAILING NORTHERN STREAM SYSTEM THAT ROTATES ACROSS
LOWER MICHIGAN SUNDAY NIGHT ON THE NORTHERN STREAM. THIS BRINGS TO
COLDEST AIR THIS AREA HAS SEEN SINCE THE AROUND THE 12TH OF
FEBRUARY. HIGH TEMPERATURES WILL BE BELOW FREEZING SUNDAY ACROSS
JUST ABOUT ALL OF THE CWA. WITH THAT COLD AIR COMING IN I EXPECTED
ENHANCED LAKE EFFECT SNOW SHOWERS AS THERE IS GOOD UPPER AIR
SUPPORT AND DECENT LOW LEVEL WIND CONVERGENCE ON THE FRONT. SO I
HAVE HIGH POPS SUNDAY NIGHT WEST OF US-131. SNOWFALL SHOULD BE
LIMITED AS THE SNOW WILL MOSTLY HAPPEN AS THE FRONT DROPS SOUTH.
ONCE THE FRONT IS THROUGH WINDS BECOME NORTH DURING THE DAY SUNDAY
SO SNOW SHOWERS WILL MOSTLY BE NEAR THE LAKE SHORE. SUNDAY NIGHT
THE HIGH MOVES IN AND ANY SNOW SHOWERS SHOULD DIMINISH. THE UPPER
LEVEL JET CROSSING SOUTHWEST LOWER MICHIGAN EARLY MONDAY WILL
CAUSE THE INVERSION HEIGHT TO CRASH TOO... FARTHER LIMITING THE
POTENTIAL FOR SNOW SHOWERS.
HIGH PRESSURE RULES MONDAY DURING THE DAY INTO TUESDAY. THEN THE
NEXT SYSTEM DURING THE WEDNESDAY TO THURSDAY TIME FRAME. THERE ARE
BIG DIFFERENCES BETWEEN THE GFS AND ECMWF AS THE ECMWF HAS A MUCH
LARGER UPPER RIDGE OVER THE WEST COAST... CAUSING A MUCH DEEPER
TROUGH OVER THE CENTRAL UNITED STATES. THE ECMWF BRINGS EVEN
COLDER AIR IN BEHIND THAT SYSTEM THURSDAY INTO FRIDAY THAN THIS
WEEKEND. WITH THE GFS BEING MUCH FLATTER... NOT MUCH COLD AIR
FOLLOWS. GIVEN THE VARIABILITY ON THE MODELS AND THAT EVEN THE
ECMWF HAS NOT BEEN VERY CONSISTENT WITH THIS I WENT HALF WAY
BETWEEN THE TOO MODELS. FOR NOW THROUGH BOTH SUGGEST EVERY WARM
WEATHER WITH SHOWERS WEDNESDAY AHEAD OF THE COLD FRONT. THE ISSUE
STARTS THURSDAY ONCE THE COLD AIR COMES IN. WE WILL HAVE TO WATCH
THIS FOR ANOTHER POSSIBLE WINTER WEATHER EVENT.
&&
.AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT)
ISSUED AT 1150 PM EST FRI MAR 2 2012
WINDS WILL CONTINUE TO GUST OVER 30 KNOTS INTO SATURDAY AS THE STORM IS
ONLY SLOWLY PULLING AWAY FROM THE REGION. IFR CONDITIONS WILL
DIMINISH OVERNIGHT TO MVFR...HOWEVER ANOTHER SURGE OF MOISTURE
MOVES IN FROM THE WEST ON SATURDAY. AS A RESULT SNOW SHOULD
INCREASE AGAIN AFTER DAYBREAK. BY 00Z SUN...THE BULK OF THE
IMPACTS FROM THE SNOW SHOULD BE OVER AS DRIER AIR MOVES IN FROM
THE WEST.
&&
.MARINE...
ISSUED AT 445 PM EST FRI MAR 2 2012
UPGRADED THE GALE WARNING TO A STORM WARNING FOR TONIGHT AS
INTENSE LOW GOES BY. GALES STILL POSSIBLE EARLY SATURDAY BEFORE
A GRADUAL DIMINISHING TREND THROUGH SATURDAY NIGHT AND SUNDAY.
&&
.HYDROLOGY...
ISSUED AT 445 PM EST FRI MAR 2 2012
RIVER LEVELS ARE HIGH DUE TO RECENT RAINS... AND UP TO ANOTHER
INCH OF RAIN MAY FALL TONIGHT. LOCALLY HIGHER AMOUNTS ALSO
POSSIBLE. AT THIS TIME... EVEN WITH FUTURE QPF FACTORED IN... NO
SITES ARE FORECAST TO REACH OR EXCEED FLOOD STAGE. SEVERAL SITES
HOWEVER ARE IN FLOOD ADVISORIES... INCLUDING... GRAND RIVER AT
IONIA... PORTAGE RIVER NEAR VICKSBURG... GRAND RIVER AT JACKSON...
SYCAMORE CREEK AT HOLT... MAPLE RIVER AT MAPLE RAPIDS... AND
THORNAPPLE RIVER ABOVE HASTINGS.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...HIGH WIND WARNING UNTIL 7 AM EST SATURDAY FOR MIZ046-051-052-
056>059-064>067-071>074.
WINTER STORM WARNING UNTIL 1 PM EST SATURDAY FOR MIZ037>040-
043>045-050.
LM...STORM WARNING UNTIL 7 AM EST SATURDAY FOR LMZ844>849.
&&
$$
UPDATE...MJS
SHORT TERM...MEADE/LAURENS
LONG TERM....WDM
AVIATION...MJS
MARINE...MEADE
HYDROLOGY...MEADE
AREA FORECAST DISCUSSION...UPDATED
NWS GRAND FORKS ND
1148 PM CST FRI MAR 2 2012
.DISCUSSION...WILL ALLOW WINTER WX ADVISORY FOR THE NORTHEAST FA
EXPIRE AT MIDNIGHT. WINDS HAVE DIMINISHED SLIGHTLY AND MOST
VISIBILITIES ARE NOW ABOVE 2SM...PLUS THE SNOWBANDS HAVE MOVED
EAST. DRIFTING SNOW WILL CONTINUE TO CAUSE ICY ROADS...AND
MENTIONED THIS IN THE EXPIRATION STATEMENT.
WILL MAINTAIN THE WINTER WX ADVISORY FOR THE NE FA AS LIGHT SNOW
CONTINUES.
&&
.AVIATION...SLOW PROGRESSION OF SFC LOW AND PRESENCE OF WRAP
AROUND MOISTURE WILL KEEP CIGS/VSBY DOWN INTO MVFR/IFR TERRITORY
THRU THE TAF PERIOD (POSSIBLE VFR CONDITIONS THIS AFTERNOON).
&&
.PREV DISCUSSION... /ISSUED 715 PM CST FRI MAR 2 2012/
DISCUSSION...WASKISH WAS REPORTING 1/4SM VSBY FOR THE PAST FEW
HOURS...AND MAKE SOME CALLS TO THAT AREA. IT APPEARS A HEAVY SNOW
BAND SET UP ACROSS NORTHERN BELTRAMI COUNTY AND SOUTHERN LAKE OF
THE WOODS COUNTY AND DROPPED 4-5 INCHES (OF COURSE RADAR
OVERSHOOTS THIS AREA). REPORTS AND OBS INDICATE VSBY IMPROVING...SO
THIS BAND MUST BE BREAKING UP. THIS AREA WAS IN A FAVORABLE
BANDING ENVIRONMENT...SO NOT TOTALLY SURPRISED. MODELS INDICATE
ANOTHER 1-3 INCHES POSSIBLE OVERNIGHT SO ISSUED A WINTER WX
ADVISORY. THESE TOTAL SNOW AMOUNTS ARE CLOSE TO WARNING
CRITERIA...BUT THINK SINCE CURRENT HEAVY BAND IS OVER...AND
REMAINDER OF SNOW WILL FALL OVER A 12 HOUR PERIOD THAT ADVISORY IS
THE WAY TO GO. UPDATED GRIDS AND PRODUCTS HAVE BEEN SENT.
CONDITIONS ARE SLOWLY IMPROVING ACROSS THE OTHER WINTER WX
ADVISORY...BUT STILL SOME REPORTS OF POOR VSBY IN OPEN COUNTRY AND
WILL LET THIS ADVISORY RIDE FOR A WHILE LONGER...ESPECIALLY SINCE
IT IS NOW DARK.
DO NOT PLAN ANOTHER UPDATE UNLESS IT IS NEEDED.
PREV DISCUSSION... /ISSUED 501 PM CST FRI MAR 2 2012/
DISCUSSION...WINDS HAVE INCREASED ACROSS MUCH OF EASTERN NORTH
DAKOTA SUSTAINED AROUND 30 MPH. CALLS TO LAW ENFORCEMENT AND WEB
CAMS INDICATE THAT VISIBILITIES IN OPEN COUNTRY ARE 1/2SM OR LESS
AT TIMES ACROSS MUCH OF THE NORTHERN RED RIVER VALLEY DUE TO
MAINLY BLOWING SNOW. THUS...WILL EXPAND THE WINTER WX ADVISORY
INTO THIS AREA FOR BLOWING SNOW. VISIBILITIES REMAIN DECENT ACROSS
THE SOUTHWEST FA...BUT WOULD NOT BE SURPRISED IF BLOWING SNOW
BEGINS TO CAUSE PROBLEMS AS THE TEMPERATURE DROPS (AS IT DID
ACROSS THE NORTH WHEN THE SNOW STARTED BLOWING AROUND). WILL
MONITOR THIS AREA...JUST NOT SURE IF WINDS WILL BE STRONG ENOUGH
BY THE TIME THE TEMPS ACTUALLY DROP.
THE WET ROADS FROM THE AFTERNOON ARE BECOMING ICY AS WELL.
UPDATED FORECAST TO EXPAND AREAS OF BLOWING SNOW INTO THE NEW
ADVISORY AREA...AND PATCHY BLOWING SNOW ACROSS THE SOUTHWEST FA.
INCREASED WIND SPEEDS A BIT. CONTINUED COLD AIR ADVECTION...925MB
WINDS 30-35 KNOTS...AND INCREASED SFC PRESSURE GRADIENT SHOULD
KEEP ELEVATED WINDS THROUGH MIDNIGHT (EVEN WITH LOSS OF SOLAR).
PREV DISCUSSION... /ISSUED 218 PM CST FRI MAR 2 2012/
SHORT TERM...
WINDS INCREASING OVER THE RED RIVER VALLEY THIS AFTERNOON INTO THE
EVENING AND WILL MAINTAIN WINTER WX ADVISORY OVER THE FAR NORTH AS
VSBYS REMAIN POOR. AREAS FROM LANGDON TO CAVALIER AND WALHALLA
RECEIVED AROUND 5 OR 6 INCHES OF FRESH SNOW FROM LAST EVENING INTO
THIS MORNING AND THESE WINDS WILL CONTINUE CAUSE REDUCED
VISIBILITY DUE TO BLOWING SNOW.
CANADIAN AND US RADAR COMPOSITE SHOWS THE MAIN SNOW BANDS NOW
WEAKENING OVER THE AREA WITH JUST LIGHT SNOW CONTINUING TO MOVE
SOUTH AND WRAP AROUND THE 500 MB LOW WHICH IS OVER GRAND FORKS AT
19Z. EXPECT TO SEE CONTINUED LIGHT SNOW INTO THE EVENING WITH A
GRADUAL SPREAD EAST IN TIME AND ENDING FROM THE WEST AS THE NIGHT
PROGRESSES. AN INCH OR SO IN NORTHWEST MN TONIGHT SEEMS REASONABLE
WITH LESS THAN THAT IN OTHER AREAS. FOR THE HEAVIER SNOWPACK AREAS
OF THE SOUTHERN VALLEY BLOWING SNOW SHOULD NOT BE A HUGE ISSUE AS
THE SNOW PACK IS QUITE HEAVY FROM PREV WET SNOW AND SNOWFALL THIS
AFTN-EVE NOT ENOUGH TO CAUSE ISSUES. BUT EVE SHIFT CAN MONITOR.
WINDS WILL BE GUSTY TO 35 MPH AT TIMES...WITH RUC AND OTHER SHORT
TERM MODELS SHOWING MIXING UP TO NR 925 MB WHERE WINDS WILL BE
30-35 KTS THRU 06Z. BORDERLINE WIND ADVISORY....BUT SUSTAINED
LIKELY JUST BLO THRESHOLDS.
WEAK RIDGE OF HIGH PRESSURE WILL BUILD EAST INTO ERN ND SATURDAY
WITH SOME CLEARING EXPECTED OVER ERN ND INTO THE VALLEY. DEPARTING
SYSTEM WILL GENERATE LEFTOVER LIGHT SNOW/FLURRIES IN FAR EASTERN
FCST AREA UNTIL NOON. HIGH PRESSURE WILL MOVE INTO MN SAT NIGHT.
DID REMOVE THE WIDESPREAD LOW POPS WE HAD IN THE FCST FOR ERN ND
INTO THE RED RIVER VALLEY SATURDAY AND REMOVED POPS FOR NW MN SAT
AFTN-NIGHT. WITH HIGH OVERHEAD AND POTENTIAL FOR CLEARING LOOKS
CHILLY AT NIGHT WITH OVERNIGHT LOWS SAT NIGHT IN THE SINGLE DIGITS
IN MANY AREAS.
NEXT THREAT FOR SOME LIGHT SNOW WILL BE OVERNIGHT SATURDAY NIGHT
AND INTO SUNDAY MAINLY OVER ERN ND INTO THE SRN VALLEY AS A WEAK
SHORT WAVE DROPS THRU CNTRL ND INTO ERN SD/SW MN. PRECIP WITH THIS
SYSTEM QUITE WEAK.
HIGH PRESSURE TO BUILD IN SUN NIGHT THEN WINDS WILL TURN SOUTH-
SOUTHWEST ON MONDAY AS A STORM SYSTEM GATHERS STRENGTH OVER
ALBERTA. THIS SHOULD BRING MILDER AIR INTO THE REGION.
LONG TERM (MON NIGHT-FRI)...
MODELS INITIALIZED WELL THIS RUN...BUT SOME DIFFERENCES SHOWING UP
IN PLACEMENT OF THE SFC FRONT FOR TUESDAY. OVERALL TRENDS STILL LOOK
GOOD FOR SHIFT TO A PROGRESSIVE PATTERN THROUGH THE END OF THE
PERIOD. THUS...CONTINUED TO LOOK AT A BLEND FOR THE GENERAL TIMING
OF THE FEATURES. THE 500HPA RIDGE IS EXPECTED TO SHIFT EAST WITH
THICKNESS VALUES INCREASING...SO EXPECTING TEMPS TO BE NEAR OR
SLIGHTLY ABOVE SEASONAL NORMS. BY THE END OF THE PERIOD...LOOK FOR
ANOTHER COLD FRONTAL PASSAGE...WITH ANOTHER CHANCE FOR MEASURABLE
PCPN.
&&
.FGF WATCHES/WARNINGS/ADVISORIES...
ND...NONE.
MN...WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR MNZ006-009.
&&
$$
TG
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1252 AM EST SAT MAR 3 2012
.SYNOPSIS...
SHOWERS AND THUNDERSTORMS WITH COLD FRONT LATE FRIDAY...SOME STORMS
COULD BE STRONG TO SEVERE. COOLER WEATHER ESTABLISHES FOR THE
WEEKEND INTO EARLY NEXT WEEK.
&&
.NEAR TERM /THROUGH TODAY/...
UPDATE...
THINGS FINALLY SETTLING DOWN AFTER ONE OF THE MORE ACTIVE DAYS
SEEN AROUND THE CWA. LAPS DATA SHOWS THE COLD FRONT PLOWING INTO
THE MOUNTAINS...AND WILL SEE WINDS INCREASING BEHIND THE FRONT.
HELD POPS IN OVER THE MOUNTAINS...AND HAVE WATER VAPOR SATELLITE
TRENDS OF HOLDING THE MOISTURE OVER THIS AREA THROUGH AROUND THE
12Z TIME FRAME. THE BULK OF THE PRECIPITATION HAS ENDED HOWEVER.
PREVIOUS DISCUSSION...
SHOWERS AND THUNDERSTORMS ASSOCIATED WITH AN APPROACHING WARM FRONT
AND MOISTURE PUNCH HAVE BEEN ONGOING ACROSS THE FORECAST AREA SINCE
MID MORNING. WRFNMM...HRRR...AND CURRENT RADAR HAVE SOME SMALL
TIMING DIFFERENCES...HOWEVER ALL AGREE THAT THERE WILL BE A BREAK IN
THE SHOWERS AND STORMS FOLLOWING THE WARM FRONT...PRIOR TO THE COLD
FRONT ARRIVING LATER THIS EVENING. RECENT RUC BUFKIT SOUNDINGS SHOW
JUST OVER 500J/KG CAPE IN EASTERN KY/WESTERN WV AHEAD OF THE COLD
FRONT LATER THIS EVENING...SO STILL THINKING STRONG TO SEVERE
THUNDERSTORMS POSSIBLE AHEAD OF THE FRONT. WITH THE TIME OF DAY THE
STORMS ARE EXPECTED...WE MAY SEE DECREASING THERMODYNAMICS AS THE
STORMS MOVE INTO CENTRAL WV. HOWEVER WITH PLENTY OF SHEAR AND
DYNAMIC LIFT FROM THE FRONT...STORMS SHOULD STILL BE ABLE TO SUPPORT
DAMAGING WINDS AND HAIL...AND POSSIBLY AN ISOLATED TORNADO.
COLD FRONT PASSAGE EXPECTED FROM FROM NW TO SE AROUND 03-06Z
TONIGHT. PRECIP CHANCES DECREASE QUICKLY AFTER THE FRONT MOVES
THROUGH.
NOT A REAL STRONG COLD PUNCH IMMEDIATELY AFTER THE FRONT...AND WITH
SOME GUSTY WINDS HANGING AROUND...WILL REMAINED WELL MIXED SO TEMPS
SHOULD REMAIN FAIRLY STEADY MOST OF THE NIGHT WITH A GRADUALLY
DECREASE THROUGH THE EARLY MORNING HOURS. TRENDED TOWARDS THE MET
AND THEN MADE SOME MINOR TWEAKS TO HOLD THE TEMPS STEADIER AT FIRST.
&&
.SHORT TERM /TONIGHT THROUGH 6 PM SUNDAY/...
CAA REGIME SETTING UP FOR THE WEEKEND. SAT SHOULD SEE SUN EARLY
BEFORE STRONGER CAA LATE IN THE DAY ALLOWS FOR STRATOCU AND CU TO
DEVELOP AS UPR TROF PIVOTS IN. DESPITE H85 TEMPS -2 TO -6....THINK
ENOUGH MIXING WILL OCCUR FOR THE WARMER NUMBERS OFF GUIDANCE TO
BECOME REALIZED. FLOW COMES MORE CONDUCIVE FOR UPSLOPE SUN INTO SUN
NIGHT AS UPR TROF AXIS SWINGS THRU. INHERITED SNOW/POP GRIDS
GENERALLY LOOKED GOOD AND ONLY NEEDED SOME FINESSING. ALLOWED FOR A
HIGH THRESHOLD FOR RAIN/SNOW DURING DAY SUN BASED ON TEMPS ALOFT.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
THIS PERIOD WILL BE CHARACTERIZED BY AN EXITING UPPER LEVEL
SHORTWAVE WITH UPPER LEVEL RIDGING BUILDING IN TUE...FOLLOWED BY THE
POSSIBILITY OF A COLD FRONT IN THE AREA LATE IN THE PERIOD.
EXTENDED MODEL GUIDANCE IS IN GOOD AGREEMENT MON EVE-WED...DEPICTING
THE EXITING SHORTWAVE WHICH WILL AFFECT OUR AREA SUN-EARLY MON
FOLLOWED BY UPPER LEVEL RIDGING OVER THE EASTERN CONUS TUE-WED.
THOUGH TUE MORNING WILL BE RATHER COLD...THE PERIOD WILL BE DRY WITH
A WARMING TREND BEGINNING TUE AFTERNOON. BY LATE WED MODEL OUTPUT
BEGINS TO DIFFER WITH RESPECT TO THE SPEED OF AN UPPER LEVEL TROUGH
DIGGING SOUTHEASTWARD ACROSS THE NORTH CENTRAL U.S. AND ITS
ASSOCIATED COLD FRONT. THE GFS DEPICTS A MUCH QUICKER PROGRESSION
WITH COLD FRONT ABOUT OVER OUR FORECAST AREA BY 06Z-12Z THU WITH
NICE WEATHER FRI...WHILE THE EC SHOWS A MUCH SLOWER PROGRESSION WITH
THE COLD FRONT OVER THE AREA FRIDAY. GFS ENSEMBLE MEAN AND ITS
MEMBERS...AND TO A LESSER EXTENT THE CANADIAN...IN MUCH BETTER
AGREEMENT WITH SLOWER SOLUTION AND WILL THUS LEAN THE FORECAST FOR
THIS TIME FRAME TOWARDS THE EC WITH THURSDAY HAVING AN INCREASE IN
HIGH CIRRUS WITH THE NEXT SHOT A SHOWERS COMING ON FRIDAY WITH THE
FRONT.
&&
.AVIATION /05Z SATURDAY THROUGH WEDNESDAY/...
SHOWERS AND REMAINING ISOLATED THUNDER CURRENTLY IN THE
MOUNTAINS...AND COULD LINGER THERE THROUGH 12Z. WILL ALSO CONTEND
WITH SOME LINGERING MVFR CEILINGS UNTIL THE FRONT CAN FINALLY
CLEAR THE AREA. WINDS WILL INCREASE BEHIND THE FRONT WITH GUSTS
FROM 20-30KTS INTO SATURDAY...WITH A GRADUAL EASING OF THESE
VELOCITIES INTO SATURDAY NIGHT. LOW LEVEL MOISTURE WILL BE ON THE
RETURN...AND COULD SEE MVFR CEILINGS BACK IN PLAY TOWARDS THE END
OF THE TAF PERIOD/06Z TIME FRAME.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z SUNDAY...
FORECAST CONFIDENCE: MEDIUM TO HIGH.
ALTERNATE SCENARIOS: MAY SEE CEILING AND VISIBILITIES BOUNCE FROM
MVFR TO VFR AT EKN AND BKW WITH SHOWERS LINGERING THERE.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
DATE SAT 03/03/12
UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
EST 1HRLY 01 02 03 04 05 06 07 08 09 10 11 12
CRW CONSISTENCY H M M H M H H M H H H H
HTS CONSISTENCY H H H H H H H H H H H H
BKW CONSISTENCY M M M M M M H L M M H H
EKN CONSISTENCY L M L L L L L L M M H H
PKB CONSISTENCY H H H H L H H H H H H H
CKB CONSISTENCY M H H H H H H L M H H H
AFTER 06Z SUNDAY...
MVFR TO IFR POSSIBLE IN MOUNTAIN SNOW SHOWERS SATURDAY EVENING THROUGH
SUNDAY.
&&
.RLX WATCHES/WARNINGS/ADVISORIES...
WV...FLASH FLOOD WATCH UNTIL 5 AM EST EARLY THIS MORNING FOR WVZ005-
006-013>015-024>027-033>038-046-047.
OH...NONE.
KY...FLASH FLOOD WATCH UNTIL 5 AM EST EARLY THIS MORNING FOR KYZ105.
VA...FLASH FLOOD WATCH UNTIL 5 AM EST EARLY THIS MORNING FOR VAZ003-
004.
&&
$$
SYNOPSIS...MZ/GG/30
NEAR TERM...MZ/26
SHORT TERM...30
LONG TERM...GG
AVIATION...26
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1158 PM EST FRI MAR 2 2012
.SYNOPSIS...
STRONG LOW PRESSURE OVER THE MIDWEST HAD A WARM FRONT EXTENDING
EAST INTO THE CAROLINAS AND COLD FRONT TRAILING BACK INTO TEXAS.
THIS LOW WILL DEEPEN AND MOVE RAPIDLY NORTHEAST INTO THE GREAT
LAKES BY SATURDAY MORNING WITH THE COLD FRONT MOVING OFF THE EAST
COAST BY LATE SATURDAY. COOLER HIGH PRESSURE BUILDS IN FOR SUNDAY
THROUGH WEDNESDAY.
&&
.NEAR TERM /THROUGH SATURDAY/...
AS OF 745 PM EST FRIDAY...
UPDATED TO ADJUST LOW TEMPS BASED ON CURRENT COLD READINGS ONGOING
WITHIN THE WEDGE AND TO SPEED UP POPS WITH THE INBOUND CONVECTION
TO THE WEST. STILL IFFY AS TO HOW FAR EAST ANY OF THE STRONGER
CELLS WILL MAKE IT GIVEN SUCH DIFFERENCES IN STABILITY/THETA-E ACROSS
THE WESTERN SLOPES. HOWEVER LOOKS LIKE DYNAMICS AND WIND FIELDS
ALOFT MAY BE ENOUGH TO PUSH SOME OF THESE CELLS INTO THE FAR
WESTERN ZONES BEFORE THEY FADE OR BECOME ELEVATED SO KEEPING
STRONG WIND MENTION THERE AS WELL AS THE GOING FLASH FLOOD WATCH.
LATEST HRRR ALSO A BIT FASTER IN BRINGING THE INITIAL BAND OF
CONVECTION INTO THE FAR NW BY 10-11 PM...THEN SLOWING A BIT OR
REDEVELOPING OVER THE SW ZONES AFTER MIDNIGHT WHERE INSTABILITY
MAY START TO RECOVER AS DEEPENING WARM ADVECTION TO THE SW STARTS
TO WIN OUT. ELSW FEW CHANGES WITH WHATS LEFT OF THE CONVECTIVE
BANDS EXPECTED TO PUSH EAST TOWARD THE BLUE RIDGE AND WEAKEN
BEFORE LIKELY REDEVELOPING IN THE PIEMDONT LATE AS WHATS LEFT OF
THE WEDGE GIVES WAY. EXPECT TEMPS ABOUT AT THEIR LOW POINT ATTM
WITH READINGS LIKELY TO RISE AND PERHAPS QUICKLY AFTER MIDNIGHT AS
THE DEEPER WARMING AHEAD OF THE FRONT ARRIVES.
AS OF 330 PM EST FRIDAY...
DEEPENING SURFACE LOW OVER THE MID-MISSISSIPPI VALLEY EXPECTED TO
TRACK NORTH INTO THE GREAT LAKES TONIGHT WITH TRAILING FRONT TO
DRIVE SOUTHEAST AND ACRS THE CWA LATE TONIGHT. MEANWHILE OVERRUNNING
RAINFALL AND EMBEDDED CONVECTION TO THE NORTH OF THE WARM FRONT
LOCATED ACROSS THE CAROLINAS THIS AFTERNOON WILL CONTINUE
LATE THIS AFTERNOON AND INTO THIS EVENING AS INCREASINGLY MOIST AIR
IS LIFTED NORTHEAST WITH THE STRONG H85 MOISTURE TRANSPORT. PWATS
SOUTH OF THE WARM FRONTAL BOUNDARY QUITE HIGH WITH 1.1 TO 1.3 INCHES
OR UP TO 200 PERCENT OF NORMAL. LOCAL WRF SHOWS THIS SCATTERED
ACTIVITY PERSISTING WELL INTO THE EVENING AND THEN THE MAIN FRONTAL
BOUNDARY ENTERING THE CWA AROUND 05Z IN THE FAR WEST AND EXITING THE
SOUTHEAST CWA AROUND 12Z. NAM A LITTLE SLOWER AND FURTHER SOUTH WITH
HEAVIEST RAINFALL. STILL EXPECT A ROUND OF STRONG TO SEVERE STORMS
ALONG THIS BOUNDARY WITH STRONG SHEAR EXPECTED TO BE IN PLACE
ALTHOUGH INSTABILITY WILL BE LESSENING. RAINFALL RATES UP TO 1 TO 2
INCHES AN HOUR ALONG THE FRONT WILL OCCUR IN AREAS THAT HAVE
RECEIVED ALREADY FROM 0.25 TO 0.75 INCHES TODAY...BASICALLY THE AREA
UNDER THE CONTINUING FLASH FLOOD WATCH WHICH THIS MAY BE ENOUGH TO
PRODUCE RUNOFF PROBLEMS.
AFTER FRONT CLEARS TOMORROW MORNING WINDS SHIFT INTO NORTHWEST AND
BECOME GUSTY WITH FAIRLY STRONG COLD AIR ADVECTION. UNDER PARTLY
CLOUDY SKIES H85 TEMPS FALL FROM +10C AROUND 06Z TO -4C IN THE NW BY
15-18Z ALTHOUGH WARMER TO THE SE. SHOULD YIELD HIGHS FROM NEAR 50 NW
TO 60 SE BUT WILL FEEL A COOLER WITH THE WIND.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
AS OF 330 PM EST FRIDAY...
CLIPPER WAVE IN THE BACKSIDE OF THE UPPER TROUGH WILL BE THE MOST
NOTABLE FEATURE OF THIS PERIOD. AT THIS TIME RANGE...MODELS ARE
TYPICALLY TOO DRY WITH THESE SYSTEMS IF H85 TEMPS ARE COLD
ENOUGH...USUALLY AROUND -8C. THIS APPEARS TO BE THE CASE FOR NW
NC...SE WV OR EXTREME SW VA. HARD TO PINPOINT THE CLIPPER`S TRACK AS
IT WILL FLUCTUATE NORTH AND SOUTH OVER THE NEXT COUPLE OF DAYS. THE
POTENTIAL EXISTS FOR A 1 TO 4 INCH SNOWFALL BLF/JFZ/GEV/TNB
CORRIDOR...MAYBE AS FAR NORTH AS WYTHEVILLE OR FLOYD COUNTY LATE
SUNDAY NIGHT AND EARLY MONDAY MORNING. OF COURSE WE WILL BE FIGHTING
A WARM GROUND. ALTHOUGH THE PROFILE ISN`T AS COLD...THIS DISTURBANCE
IS TAKING A SIMILAR PATH AND IS A LITTLE WEAKER THAN THE STORM WHICH
DUMPED A SURPRISE SEVERAL INCHES ON FLOYD COUNTY SEVERAL WEEKS AGO.
WITH CONTINUED CAA BEHIND THE WAVE MONDAY TEMPS WILL PROBABLY GO NO
WHERE OR ONLY RISE A FEW DEGREES IN THE MOUNTAINS...SO MAX T WAS
LOWERED.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
AS OF 207 PM EST THURSDAY...
STRONG RIDGE OF HIGH PRESSURE WILL ANCHOR ITSELF ALONG THE EAST
COAST THROUGH AT LEAST WEDNESDAY...MAY BE THURSDAY. A COLD FRONT
WILL THEN SWEEP ACROSS THE REGION AS EARLY AS THURSDAY AFTERNOON BUT
MORE LIKELY FRIDAY. THE GFS IS QUICK WITH THIS FRONT WHILE HPC/ECMWF
ARE SLOWER WITH THE FRONTAL PASSAGE ON FRIDAY. KEEP POPS AT A CHANCE
WITH LOW CONFIDENCE ON TIMING.
TEMPERATURES WILL BE SEASONAL ON TUESDAY THEN MODERATE ABOVE NORMAL
WEDNESDAY INTO FRIDAY. TEMPERATURES THURSDAY COULD BE 10F-15F ABOVE
NORMAL AND POSSIBLY WARMER ON FRIDAY IF RAIN HOLDS OFF UNTIL THE
AFTERNOON.
&&
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
AS OF 1130 PM EST FRIDAY...
RESIDUAL CONVECTIVE BAND NOW HEADING OUT TO THE BLUE RIDGE WITH
AREAS OF HEAVY RAIN AND GUSTY WINDS. HOWEVER WEDGE CONTINUES TO
HOLD TIGHT EXCEPT AT KBLF WHERE HAVE BRIEFLY MIXED OUT INTO THE
WARM AIR. THIS LOW LEVEL MOISTURE AND INCREASING RAINFALL RESULTING
IN WIDESPREAD MVFR/IFR CIGS...AND MVFR VSBYS IN FOG ATTM. GIVEN
STRONGER PUSH OF WARM AIR ALOFT AHEAD OF THE FRONT OVERNIGHT EXPECTING
CIGS TO REMAIN LOW WITH IFR OR EVEN AREAS OF LIFR UNTIL THE WARM
AIR BECOMES DEEP ENOUGH TO SCOUR OUT THE LOWER CIGS MAINLY
EAST...LIKELY WHEN THE PRE- FRONTAL CONVECTION ARRIVES LATER THIS
EVENING. THUS KEEPING POOR FLYING CONDITIONS IN CLOUDS/FOG FOR A
WHILE OVERNIGHT WITH A MORE ORGANIZED AREA OF SHRA/TSRA PUSHING
ACROSS THE BLUE RIDGE AFTER MIDNIGHT...THEN EASTERN SECTIONS
DURING THE EARLY MORNING HOURS. WINDS ALOFT WILL REMAIN VERY
STRONG RESULTING IN CONTINUED LLWS FOR MOST SPOTS UNTIL BETTER
MIXING ARRIVES WITH THE CONVECTION BY MORNING.
ACTUAL COLD FRONT LOOKS TO PUSH THROUGH MOST OF THE REGION BETWEEN
1 AM AND DAYBREAK...WITH A WIND SHIFT TO THE NORTHWEST DURING THE
LATE NIGHT HOURS. WINDS WILL BE STRONG AND GUSTY BEHIND THE FRONT
BUT CEILINGS SHOULD BE LIFTING AFTER DAYBREAK ON SATURDAY. STRONG
MIXING BEHIND THE FRONT SHOULD COMBINE WITH GOOD DRYING TO PROMOTE
A RETURN TO VFR ALL AREAS AFTER MID MORNING SAT. HOWEVER SURFACE
WINDS SHOULD REMAIN STRONG WITH GUSTS TO 30 KTS OR MORE ESPCLY
KBLF TO KROA SAT AFTERNOON.
ANOTHER SHORT WAVE BRINGS A SECONDARY FRONT AND COLDER AIR IN FOR
SUNDAY NIGHT INTO EARLY MONDAY. EXPECT MOUNTAIN RAIN AND SNOW
SHOWERS WITH MVFR CEILINGS...ESPECIALLY AT BLF AND LWB SUNDAY
THROUGH MONDAY. HIGH PRESSURE WITH DRIER AIR AND VFR CONDITIONS
BUILDS IN FOR TUESDAY/WEDNESDAY.
&&
.HYDROLOGY...
HPC HAS MAINTAINED SLIGHT RISK OF EXCESSIVE RAINFALL ALONG OUR
ABOUT OUR WESTERN CWA BORDER WITH RAINFALL RATES OF 1 TO 1.5
INCHES PER HOUR POSSIBLE IN THE OVERNIGHT STORMS. FLASH FLOOD
WATCH REMAINS IN EFFECT FOR WESTERN COUNTIES WHICH IS ALSO WHERE
HEAVIER RAIN FELL EARLIER THIS WEEK. TOTAL QPF NOT EXPECTED TO BE
BE TOO HIGH...GENERALLY LESS THAN 1 INCH BUT WITH HIGH RATE
RAINFALL IN EMBEDDED THUNDERSTORMS LATER TODAY AND TONIGHT COULD
SEE RAPID RUNOFF IN SOME AREA. SMALL STREAMS MAY RESPOND RAPIDLY
IN THE WATCH AREA.
LARGER RIVERS ARE NEARING CREST NOW ON THE MIDDLE JAMES AND
FALLING RAPIDLY ON THE GREENBRIER AND UPPER JAMES. FORECAST
RAINFALL NOT EXPECTED TO BRING RIVERS BACK TO FLOOD STAGE BUT MAY
PROLONG RECESSION BY 12 TO 24 HOURS.
&&
.RNK WATCHES/WARNINGS/ADVISORIES...
VA...FLASH FLOOD WATCH UNTIL 6 AM EST SATURDAY FOR VAZ007-019-020.
NC...NONE.
WV...FLASH FLOOD WATCH UNTIL 6 AM EST SATURDAY FOR WVZ042>045.
&&
$$
SYNOPSIS...PC
NEAR TERM...JH/PC
SHORT TERM...RCS
LONG TERM...KM
AVIATION...JH/PC/WERT
HYDROLOGY...
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1042 AM EST SAT MAR 3 2012
.SYNOPSIS...
STRONG WINDS BEHIND A COLD FRONT WILL USHER IN COLDER AIR TODAY
AND SUNDAY. A COLD WEST-NORTHWESTERLY FLOW OFF OF THE LAKES WILL
ALLOW FOR SNOW SHOWERS ACROSS THE AREA TONIGHT INTO SUNDAY. A
CLIPPER SYSTEM WILL PASS SOUTH OF THE AREA SUNDAY NIGHT INTO
MONDAY WITH TRAILING HIGH PRESSURE ALLOWING FOR A DRY MID-WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
15Z ENHANCED SHORT TERM FORECAST UPDATE HAS BEEN ISSUED TO
INCREASE CLOUD COVERAGE ACROSS EASTERN OHIO AND WESTERN PA AS A
STRATOCUMULUS DECK WORKS INTO THE AREA. LITTLE CHANGE TO THE
GOING FORECAST OTHERWISE.
THE LATEST RUC MID-LEVEL ANALYSIS INDICATES A CLOSED 500MB LOW
ACROSS ONTARIO WITH A SOUTHWESTERLY FLOW SOUTH OF THIS FEATURE ACROSS
THE UPPER OHIO VALLEY. 1000-800MB LAYER MOISTURE IS ADVECTING IN
FROM THE WEST WITH MOSTLY CLOUDY SKIES WEST OF PITTSBURGH. AT THE
SURFACE, A 982MB LOW IS LOCATED IN QUEBEC WITH A COLD FRONT
EXTENDING SOUTH OF THIS FEATURE ALONG THE EAST COAST OF THE US. A
TIGHT PRESSURE GRADIENT IS IN PLACE BETWEEN THE LOW AND A HIGH
ACROSS THE PLAINS HAS ALLOWED FOR WINDS GUSTING AT 25 TO 35 MPH
THIS MORNING.
THIS AFTERNOON...LOW-LEVEL MOISTURE WILL CONTINUE TO ADVECT INTO
THE AREA WITH CLOUD COVERAGE INCREASING FROM THE WEST. DIURNAL
MIXING WILL ALLOW FOR WIND GUSTS TO INCREASE. THE NAM BUFKIT
SOUNDING IS STILL NOT RULING OUT A FEW GUSTS THAT WILL BE
MARGINALLY NEAR WIND ADVISORY CRITERIA ACROSS THE LOWLANDS. THUS,
A LOW-END WIND ADVISORY REMAINS IN PLACE. TEMP TRENDS REMAIN ON
TRACK, A FEW DEGREES WARMER THAN LAMP GUIDANCE FOR HIGHS TODAY.
TONIGHT...WINDS WILL SUBSIDE WITH THE LOSS OF DAYTIME HEATING.
CLOUDS INCREASE FROM NORTH TO SOUTH DURING THE OVERNIGHT HOURS
AHEAD OF A MID LEVEL DISTURBANCE WITHIN BROAD CYCLONIC FLOW. THE
LOW-LEVEL FLOW WILL SHIFT FROM WESTERLY TO WEST-NORTHWESTERLY,
WITH THE CHANCE OF SNOW SHOWERS RETURNING ALONG THE I-80 CORRIDOR
BY 06Z SUNDAY. LITTLE OR NO SNOW ACCUMULATION IS EXPECTED THROUGH
DAWN. LOW TEMPS ARE A MAV/MET BLEND, NEAR SEASONAL NORMALS
TONIGHT.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
A COLD WEST-NORTHWESTERLY FLOW WITH 850 TEMPS AT -12C TO -14C WILL
ALLOW FOR LAKE EFFECT SNOW SHOWERS TO CONTINUE. LIKELY POPS ARE
FORECAST ALONG THE I-80 CORRIDOR AND EASTERN RIDGES WITH CHANCE
POPS ELSEWHERE. AN ASSOCIATED TROF REFLECTED AT BOTH 850 AND THE
SURFACE SHOULD HELP ENHANCED SNOW SHOWERS SOMEWHAT. FETCH OFF OF
THE LAKES WILL EVENTUALLY CUT OFF AS 850 RIDGE APPROACHES ON
MONDAY. SEVERAL INCHES POSSIBLE I80 AND NORTH AND
MOUNTAINS...ELSEWHERE LIGHT AMOUNTS. HIGH PRESSURE THEN BUILDS
INTO AREA.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
HIGH PRESSURE WILL DOMINATE THE REGION THROUGH THURSDAY. SOUTHWEST
FLOW TO INCREASE WEDNESDAY INTO THURSDAY WITH INCREASE IN WINDS.
PROBABLY GUSTY ESPECIALLY IN THE AFTERNOON. NEXT FRONT APPROACHES EARLY
THURSDAY WITH CHANCE SHOWERS. DISCREPANCY BETWEEN ECMWF AND GFS ON
HANDLING NEXT FRONT. GFS BRINGS IN PRECIPITATION THURSDAY MORNING
AND EVENTUALLY LAYS FRONT OUT EAST TO WEST AND HANGS ACROSS
SOUTHERN PORTION AREA BEFORE HIGH BUILDS IN ON SATURDAY.
MEANWHILE, ECMWF HAS SLOWER EASTWARD PROGRESSION WITH APPROACH TO
CWA ON FRIDAY AND KEEPS SHOWERS IN THROUGH THE DAY WITH SLOWER
EXIT AND RETARDS SURFACE RIDGE BUILDING INTO AREA.
&&
.AVIATION /16Z SATURDAY THROUGH WEDNESDAY/...
ALL SITES WILL BE OVERCAST BY EARLY AFTERNOON WITH LOW VFR CIGS
PREDICTED THROUGH THE DAYTIME HOURS. AFTER SUNSET...VFR CIGS WILL
RISE FOR THE OVERNIGHT HOURS. W-SW WINDS WILL BE THE BIGGEST
AVIATION CONCERN THROUGH THE TIME PERIOD...WITH WIDESPREAD 30 KT
GUSTS. MGW WILL LIKELY HAVE LIGHTER WIND GUSTS...AROUND 25
KTS...WITH FKL AND DUJ CLOSER TO 35 KTS.
OUTLOOK...SUNDAY THROUGH WEDNESDAY...
IFR WX POSSIBLE AT FKL AND DUJ SUNDAY IN SNOW SHOWERS...OTHERWISE
NO OTHER WIDESPREAD IFR WX PREDICTED.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR MDZ001.
OH...WIND ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR OHZ039>041-
048>050-057>059-068-069.
PA...WIND ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR PAZ007>009-
013>016-020>023-029-031-073-075.
WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR PAZ074-076.
WV...WIND ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR WVZ001>004-012-
021-022.
WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR WVZ023-041.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
634 AM EST SAT MAR 3 2012
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 533 AM EST SAT MAR 3 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A TROUGH DOMINATING THE CNTRL
CONUS. A POTENT MID/UPPER LEVEL LOW WAS LOCATED OVER NRN LAKE HURON.
THE STRONG FGEN/DEFORMATION ASSOCIATED WITH THIS FEATURE WAS QUICKLY
SLIDING TO THE EAST THROUGH NRN LAKE HURON. HOWEVER A LARGE SHIELD
OF PCPN ASSOCIATED WITH 285K-295 ISENTROPIC ASCENT AND 700-300 MB
QVECTOR CONV CONTINUED ACROSS LAKE SUPERIOR AND UPPER MICHIGAN.
RADAR ALSO SHOWED HIGHER RETURNS INTO N CNTRL UPPER MICHIGAN WHERE
NRLY FLOW UPSLOPE AND LAKE ENHANCEMENT (850 MB TEMPS AROUND -8C)
HAVE BOOSTED SNOWFALL RATES. AT THE SFC...A 979 MB LOW WAS LOCATED
OVER GEORGIAN BAY SUPPORTED STRONG NRLY WINDS ACROSS LAKE SUPERIOR
INTO UPPER MICHIGAN. SINCE THE SNOW TOTAL AT THE NWS OFFICE HAD
REACHED 5 INCHES BY 0930Z AND SIGNIFICANT ADDITIONAL AMOUNTS WERE
EXPECTED TODAY...UPGRADED THE ADVY TO A WARNING FOR MARQUETTE
COUNTY.
TODAY...EXPECT THE SYNOPTIC SCALE UPWARD MOTION AND PCPN SHIELD TO
GRADUALLY DIMINISH THIS MORNING AS THE MID LEVEL LOW SHIFTS TO THE
EAST. HOWEVER...WITH DEEP MOISTURE PERSISTING OVER THE AREA ALONG
WITH CAA DROPPING 850 MB TEMPS TO AROUND -15C BY 18Z...TRANSITION
TOWARD LAKE ENHANCED/EFFECT WILL KEEP AT LEAST MODERATE SNOWFALL
RATES GOING THIS MORNING. ADDITIONAL SNOWFALL AMOUNTS IN THE 3 TO 5
INCH RANGE WILL BE POSSIBLE TODAY...ESPECIALLY OVER THE EAST AND HIGHER
TERRAIN IN N CNTRL UPPER MI. OVER THE WEST...LIGHT LAKE
ENHANCED/EFFECT SNOW WILL ALSO CONTINUE WITH LOWER AMOUNTS IN THE 1
TO 3 INCH RANGE. TO THE SOUTH...THE SNOW SHOULD TAPER OFF THIS
MORNING WITH MAINLY JUST SCT -SHSN BY AFTERNOON. ALTHOUGH THE STRONG
925 MB WINDS OF 30-35 KTS MAY KEEP ACCUMULATING SNOW GOING INTO NE
AND ERN DELTA COUNTY...FARTHER TO THE SW NEAR ESC...ADDITIONAL
SNOWFALL SHOULD BE MINIMAL. DRIER SFC-800 MB LAYER AIR MOVING IN FROM
THE NORTH THIS AFTERNOON WILL BRING AN OVERALL DIMINISHING TREND WITH
THE LES.
TONIGHT...LES WILL CONTINUE TO DECREASE AS A RIDGE BUILDS INTO THE
REGION WITH LOW LEVEL WINDS DIMINISHING AND BECOMING MORE ACYC.
SINCE LIGHT TO OCNLY MODERATE SNOW MAY CONTINUE NORTH...ALLOWED WARNING
TO REMAIN IN PLACE. HOWEVER...IF SNOWFALL TRENDS DROP OFF ENOUGH AND
THE DRY AIR MOVES IN MORE AGGRESSIVELY...THE WARNINGS OVER THE NORTH
MAY BE DROPPED EARLY.
SUNDAY...ANY REMAINING N TO NE FLOW LIGHT LES SHOULD DIMINISH SUNDAY
MORNING AS INVERSION HEIGHTS DROP TO AROUND 3K FT AND LOW LEVEL WIND
FIELDS BECOME WEAK AND DISORGANIZED.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 533 AM EST SAT MAR 3 2012
GOOD AGREEMENT FM THE MEDIUM RANGE MODELS IN LARGE SCALE PATTERN
LATER THIS WEEKEND THROUGH MUCH OF THE UPCOMING WORK WEEK. COLD
TROUGH STICKS AROUND INITIALLY THROUGH SUNDAY. LIGHT NORTHERLY WINDS
AND SUFFICIENTLY COLD AIR IN LOW-LEVELS SHOULD KEEP SCATTERED LIGHT
LAKE EFFECT SNOW SHOWERS/FLURRIES GOING ALONG MUCH OF LK SUPERIOR.
DESPITE H85 TEMPS AS LOW AS -16C...ACCUMS SHOULD END UP QUITE LIGHT
AS LOW LEVEL WINDS ARE WEAK AND ANTICYCLONIC. HEADING INTO MONDAY
THE SFC RIDGE OVR ONTARIO FOR MUCH OF THE WEEKEND SETTLES INTO THE
CNTRL AND LOWER GREAT LAKES. RIDGE MOVING EAST AND TROUGH PUSHING
ACROSS SCNTRL CANADA ALLOWS BLYR WINDS TO BECOME MORE SWRLY AND
FLOW OFF LAKE SUPERIOR TO END. INDICATIONS THAT PLENTY OF CLOUDS MAY
REMAIN TRAPPED BENEATH DEVELOPING WARM AIR ADVECTION PATTERN. KEPT
SKIES PARTLY TO MOSTLY CLOUDY WITH WARMER TEMPERATURES TOWARD THE
UPR 20S/LOWER 30S.
FOR THE EXTENDED...
WARM AIR ADVECTION REGIME CONTINUES TUESDAY INTO WEDNESDAY. EARLY ON
AS STRONGER SFC LOW SLIDES ACROSS SOUTHERN TIER OF CANADA THERE
COULD BE SOME LGT SNOW TRY TO BREAK OUT OVR PORTIONS OF CWA. ECMWF
AND CANADIAN FARTHER SOUTH WITH THE SNOW WHILE GFS/NAM KEEP MAJORITY
OF SNOW OVR LK SUPERIOR AND INTO ONTARIO. MIDDLE ROAD APPROACH FOR
NOW GIVEN STRENGTH OF WARM AIR ADVECTION AND LOOK OF GFS/ECMWF LOWER
H85 DWPNT DEPRESSIONS. BETTER CHANCE OF LGT SNOW OVR THE CWA WOULD
BE MONDAY EVENING ON THE KEWEENAW AND LATER AT NIGHT OVR THE FAR
NORTHEAST CWA. WENT FOR MORE CLOUDS THAN GUIDANCE INTO TUESDAY
WITH SOUNDINGS SHOWING LOW-LEVEL MOISTURE BENEATH THE STRENGTHENING
INVERSION /H85 TEMPS PUSHING TOWARD +5C ON TUESDAY/. HIGHS ON
TUESDAY WILL BE WARM BUT COULD BE TEMPERED A BIT BY THE CLOUDS.
EVEN SO...A SHALLOW MIXING HEIGHT OF ONLY 950MB YIELDS HIGHS OVR
40 DEGREES. LEANED MORE TOWARD PREVIOUS FCST WITH MID 40S ALONG LK
SUPERIOR SHORE NW AND NCNTRL GIVEN SW WIND DIRECTION. IF WE DO SEE
SUNSHINE...HIGHER SUN ANGLE AND DENSELY FORESTED LANDSCAPE/LOWER
ALBEDO WOULD OFFSET RECENT SNOWFALL AND COULD ALLOW FOR ISOLD 50
DEGREE READINGS. SFC DWPNTS INTO THE MID 30S AND MAYBE EVEN HIGHER
FCST TO SURGE INTO UPR LAKES LATER TUESDAY INTO TUESDAY NIGHT. HAVE
ADDED FOG TO FCST MAINLY OVER INLAND AREAS WHERE TEMPS COULD DIP THE
LOWEST. AT THE LEAST...SEEMS LIKE GOOD SETUP FOR PLENTY OF STRATUS.
INCREASING SOUTHERLY WINDS WILL ALSO BE ISSUE FOR LATER TUESDAY INTO
TUESDAY NIGHT. VERY STABLE PROFILE IN LOW-LEVELS BUT EVEN SFC-BLYR
WINDS OFF MODELS POINT TO SOUTH TO SOUTHWEST WINDS NEAR GREAT LAKE
SHORES GUSTING TO 30-35 MPH ON TUESDAY NIGHT INTO WEDNESDAY MORNING.
MODELS CONTINUE TO SHOW COLD FRONT WORKING THROUGH UPR LAKES ON
WEDNESDAY AND NOW IT SEEMS LIKE TREND IS QUICKER IN BRINGING COLDER
AIR INTO WESTERN CWA. GFS SOUNDINGS AT IWD/CMX ARE ESSENTIALLY BLO
0C AS EARLY AS MID MORNING ON WEDNESDAY AND ECMWF LENDS SUPPORT TO
COLDER SCENARIO AS WELL. KEPT MIX OF RAIN/SNOW FOR CNTRL AND EAST...
BUT WENT WITH MAINLY SNOW IN THE WEST. MODEL CONSENSUS WOULD POINT
TO ADVY SNOW ACCUMS IN SOME AREAS OF THE WEST AND CENTRAL...BUT
HIGHER CERTAINTY IN THIS IDEA NOT THERE QUITE YET AS MODELS HAVE
BEEN JUMPING AROUND WITH EXTENT OF UPR WAVE LIFTING ALONG FRONT ON
WEDNESDAY AND HOW FAR WEST TO HAVE THIS WAVE. DO HAVE LIKELY POPS
NOW OVR THE EAST HALF OF THE CWA WHERE WAVE IS MOST LIKELY TO TRACK
AT THIS POINT. GRADUALLY COOLER AIR SETTLES INTO UPR LAKES TO CLOSE
THE WEEK. SOME LK EFFECT COULD OCCUR...THOUGH THERE ARE DIFFERENCES
IN GUIDANCE ON GENERAL WIND DIRECTION. NO NEED TO STRAY FM CONSENSUS
APPROACH FOR NOW...WHICH RESULTS IN SLIGHT CHANCES OF SNOW SHOWERS
THURSDAY AND FRIDAY NEAR LAKE SUPERIOR.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 632 AM EST SAT MAR 3 2012
SAW...WITH STRONG NRLY WINDS AND COLDER AIR MOVING IN WHILE THE PCPN
SHIELD REMAINS OVER THE AREA...EXPECT MODERATE SN TO PERSIST UNTIL
LATER THIS MORNING AND RESULT IN LIFR CONDITIONS AT TIMES. ONCE THE
LOW MOVES FARTHER TO THE E BY THIS AFTERNOON...DRIER AIR WILL
ARRIVE AND THE WINDS WILL SLOWLY DIMINISH...SO CONDITIONS WILL
IMPROVE TO MVFR. HOWEVER...SOME LIGHT LES MAY PERSIST THROUGH
TONIGHT.
CMX/IWD...ALTHOUGH THESE LOCATIONS ARE FARTHER W OF THE DEPARTING
LOW PRESSURE SYSTEM CYCLONIC NNE FLOW WILL SUPPORT SOME -SN AND
IFR/OCNL MVFR CONDITIONS. THE ARRIVAL OF DRIER AIR AND WEAKENING
CYCLONIC FLOW BY THIS AFTERNOON WILL CAUSE CONDITIONS TO
IMPROVE TO MVFR.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 533 AM EST SAT MAR 3 2012
NORTH GALES WILL CONTINUE TODAY AS LAKE SUPERIOR IS ON NORTHWEST
FRINGE OF STRONG LOW PRESSURE SYSTEM MOVING INTO QUEBEC. GALES
DIMINISH TONIGHT INTO SUNDAY AS HIGH PRESSURE RIDGE OVER ONTARIO
SLIDES INTO THE REGION. ONCE RIDGE SLIDES OUT TO THE EAST ON MONDAY
A STRONGER LOW PRESSURE IS FCST TO MOVE ACROSS SOUTHERN TIER OF
CANADA. TIGHTER PRESSURE GRADIENT BTWN THE RIDGE AND THE APPROACHING
LOW MAY LEAD TO 30 KT SOUTHERLY WINDS OVR EAST HALF OF LK SUPERIOR
TUESDAY NIGHT INTO WEDNESDAY. STABILITY IS HIGH...BUT IF PRESSURE
FALLS NORTH OF LK SUPERIOR ARE STRONG ENOUGH...COULD SEE GALE GUSTS
OVR EASTERN LK SUPERIOR. COLD FRONT WORKS ACROSS ON WEDNESDAY.
NORTHWEST TO NORTHERLY WINDS IN WAKE OF THE FRONT ARE EXPECTED TO
REMAIN BLO 25 KTS THURSDAY INTO FRIDAY. &&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WARNING UNTIL 7 PM EST THIS EVENING FOR MIZ013-014.
WINTER STORM WARNING UNTIL 1 AM EST SUNDAY FOR MIZ007.
WINTER WEATHER ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR
MIZ012.
WINTER STORM WARNING UNTIL 7 AM EST SUNDAY FOR MIZ005-006-085.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 4 AM EST SUNDAY FOR
LSZ243>245-248>251-263>267.
GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LSZ244-245-248>251-
264>267.
GALE WARNING UNTIL 1 PM EST THIS AFTERNOON FOR LSZ263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...JLB
MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
536 AM EST SAT MAR 3 2012
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 533 AM EST SAT MAR 3 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A TROUGH DOMINATING THE CNTRL
CONUS. A POTENT MID/UPPER LEVEL LOW WAS LOCATED OVER NRN LAKE HURON.
THE STRONG FGEN/DEFORMATION ASSOCIATED WITH THIS FEATURE WAS QUICKLY
SLIDING TO THE EAST THROUGH NRN LAKE HURON. HOWEVER A LARGE SHIELD
OF PCPN ASSOCIATED WITH 285K-295 ISENTROPIC ASCENT AND 700-300 MB
QVECTOR CONV CONTINUED ACROSS LAKE SUPERIOR AND UPPER MICHIGAN.
RADAR ALSO SHOWED HIGHER RETURNS INTO N CNTRL UPPER MICHIGAN WHERE
NRLY FLOW UPSLOPE AND LAKE ENHANCEMENT (850 MB TEMPS AROUND -8C)
HAVE BOOSTED SNOWFALL RATES. AT THE SFC...A 979 MB LOW WAS LOCATED
OVER GEORGIAN BAY SUPPORTED STRONG NRLY WINDS ACROSS LAKE SUPERIOR
INTO UPPER MICHIGAN. SINCE THE SNOW TOTAL AT THE NWS OFFICE HAD
REACHED 5 INCHES BY 0930Z AND SIGNIFICANT ADDITIONAL AMOUNTS WERE
EXPECTED TODAY...UPGRADED THE ADVY TO A WARNING FOR MARQUETTE
COUNTY.
TODAY...EXPECT THE SYNOPTIC SCALE UPWARD MOTION AND PCPN SHIELD TO
GRADUALLY DIMINISH THIS MORNING AS THE MID LEVEL LOW SHIFTS TO THE
EAST. HOWEVER...WITH DEEP MOISTURE PERSISTING OVER THE AREA ALONG
WITH CAA DROPPING 850 MB TEMPS TO AROUND -15C BY 18Z...TRANSITION
TOWARD LAKE ENHANCED/EFFECT WILL KEEP AT LEAST MODERATE SNOWFALL
RATES GOING THIS MORNING. ADDITIONAL SNOWFALL AMOUNTS IN THE 3 TO 5
INCH RANGE WILL BE POSSIBLE TODAY...ESPECIALLY OVER THE EAST AND HIGHER
TERRAIN IN N CNTRL UPPER MI. OVER THE WEST...LIGHT LAKE
ENHANCED/EFFECT SNOW WILL ALSO CONTINUE WITH LOWER AMOUNTS IN THE 1
TO 3 INCH RANGE. TO THE SOUTH...THE SNOW SHOULD TAPER OFF THIS
MORNING WITH MAINLY JUST SCT -SHSN BY AFTERNOON. ALTHOUGH THE STRONG
925 MB WINDS OF 30-35 KTS MAY KEEP ACCUMULATING SNOW GOING INTO NE
AND ERN DELTA COUNTY...FARTHER TO THE SW NEAR ESC...ADDITIONAL
SNOWFALL SHOULD BE MINIMAL. DRIER SFC-800 MB LAYER AIR MOVING IN FROM
THE NORTH THIS AFTERNOON WILL BRING AN OVERALL DIMINISHING TREND WITH
THE LES.
TONIGHT...LES WILL CONTINUE TO DECREASE AS A RIDGE BUILDS INTO THE
REGION WITH LOW LEVEL WINDS DIMINISHING AND BECOMING MORE ACYC.
SINCE LIGHT TO OCNLY MODERATE SNOW MAY CONTINUE NORTH...ALLOWED WARNING
TO REMAIN IN PLACE. HOWEVER...IF SNOWFALL TRENDS DROP OFF ENOUGH AND
THE DRY AIR MOVES IN MORE AGGRESSIVELY...THE WARNINGS OVER THE NORTH
MAY BE DROPPED EARLY.
SUNDAY...ANY REMAINING N TO NE FLOW LIGHT LES SHOULD DIMINISH SUNDAY
MORNING AS INVERSION HEIGHTS DROP TO AROUND 3K FT AND LOW LEVEL WIND
FIELDS BECOME WEAK AND DISORGANIZED.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 533 AM EST SAT MAR 3 2012
GOOD AGREEMENT FM THE MEDIUM RANGE MODELS IN LARGE SCALE PATTERN
LATER THIS WEEKEND THROUGH MUCH OF THE UPCOMING WORK WEEK. COLD
TROUGH STICKS AROUND INITIALLY THROUGH SUNDAY. LIGHT NORTHERLY WINDS
AND SUFFICIENTLY COLD AIR IN LOW-LEVELS SHOULD KEEP SCATTERED LIGHT
LAKE EFFECT SNOW SHOWERS/FLURRIES GOING ALONG MUCH OF LK SUPERIOR.
DESPITE H85 TEMPS AS LOW AS -16C...ACCUMS SHOULD END UP QUITE LIGHT
AS LOW LEVEL WINDS ARE WEAK AND ANTICYCLONIC. HEADING INTO MONDAY
THE SFC RIDGE OVR ONTARIO FOR MUCH OF THE WEEKEND SETTLES INTO THE
CNTRL AND LOWER GREAT LAKES. RIDGE MOVING EAST AND TROUGH PUSHING
ACROSS SCNTRL CANADA ALLOWS BLYR WINDS TO BECOME MORE SWRLY AND
FLOW OFF LAKE SUPERIOR TO END. INDICATIONS THAT PLENTY OF CLOUDS MAY
REMAIN TRAPPED BENEATH DEVELOPING WARM AIR ADVECTION PATTERN. KEPT
SKIES PARTLY TO MOSTLY CLOUDY WITH WARMER TEMPERATURES TOWARD THE
UPR 20S/LOWER 30S.
FOR THE EXTENDED...
WARM AIR ADVECTION REGIME CONTINUES TUESDAY INTO WEDNESDAY. EARLY ON
AS STRONGER SFC LOW SLIDES ACROSS SOUTHERN TIER OF CANADA THERE
COULD BE SOME LGT SNOW TRY TO BREAK OUT OVR PORTIONS OF CWA. ECMWF
AND CANADIAN FARTHER SOUTH WITH THE SNOW WHILE GFS/NAM KEEP MAJORITY
OF SNOW OVR LK SUPERIOR AND INTO ONTARIO. MIDDLE ROAD APPROACH FOR
NOW GIVEN STRENGTH OF WARM AIR ADVECTION AND LOOK OF GFS/ECMWF LOWER
H85 DWPNT DEPRESSIONS. BETTER CHANCE OF LGT SNOW OVR THE CWA WOULD
BE MONDAY EVENING ON THE KEWEENAW AND LATER AT NIGHT OVR THE FAR
NORTHEAST CWA. WENT FOR MORE CLOUDS THAN GUIDANCE INTO TUESDAY
WITH SOUNDINGS SHOWING LOW-LEVEL MOISTURE BENEATH THE STRENGTHENING
INVERSION /H85 TEMPS PUSHING TOWARD +5C ON TUESDAY/. HIGHS ON
TUESDAY WILL BE WARM BUT COULD BE TEMPERED A BIT BY THE CLOUDS.
EVEN SO...A SHALLOW MIXING HEIGHT OF ONLY 950MB YIELDS HIGHS OVR
40 DEGREES. LEANED MORE TOWARD PREVIOUS FCST WITH MID 40S ALONG LK
SUPERIOR SHORE NW AND NCNTRL GIVEN SW WIND DIRECTION. IF WE DO SEE
SUNSHINE...HIGHER SUN ANGLE AND DENSELY FORESTED LANDSCAPE/LOWER
ALBEDO WOULD OFFSET RECENT SNOWFALL AND COULD ALLOW FOR ISOLD 50
DEGREE READINGS. SFC DWPNTS INTO THE MID 30S AND MAYBE EVEN HIGHER
FCST TO SURGE INTO UPR LAKES LATER TUESDAY INTO TUESDAY NIGHT. HAVE
ADDED FOG TO FCST MAINLY OVER INLAND AREAS WHERE TEMPS COULD DIP THE
LOWEST. AT THE LEAST...SEEMS LIKE GOOD SETUP FOR PLENTY OF STRATUS.
INCREASING SOUTHERLY WINDS WILL ALSO BE ISSUE FOR LATER TUESDAY INTO
TUESDAY NIGHT. VERY STABLE PROFILE IN LOW-LEVELS BUT EVEN SFC-BLYR
WINDS OFF MODELS POINT TO SOUTH TO SOUTHWEST WINDS NEAR GREAT LAKE
SHORES GUSTING TO 30-35 MPH ON TUESDAY NIGHT INTO WEDNESDAY MORNING.
MODELS CONTINUE TO SHOW COLD FRONT WORKING THROUGH UPR LAKES ON
WEDNESDAY AND NOW IT SEEMS LIKE TREND IS QUICKER IN BRINGING COLDER
AIR INTO WESTERN CWA. GFS SOUNDINGS AT IWD/CMX ARE ESSENTIALLY BLO
0C AS EARLY AS MID MORNING ON WEDNESDAY AND ECMWF LENDS SUPPORT TO
COLDER SCENARIO AS WELL. KEPT MIX OF RAIN/SNOW FOR CNTRL AND EAST...
BUT WENT WITH MAINLY SNOW IN THE WEST. MODEL CONSENSUS WOULD POINT
TO ADVY SNOW ACCUMS IN SOME AREAS OF THE WEST AND CENTRAL...BUT
HIGHER CERTAINTY IN THIS IDEA NOT THERE QUITE YET AS MODELS HAVE
BEEN JUMPING AROUND WITH EXTENT OF UPR WAVE LIFTING ALONG FRONT ON
WEDNESDAY AND HOW FAR WEST TO HAVE THIS WAVE. DO HAVE LIKELY POPS
NOW OVR THE EAST HALF OF THE CWA WHERE WAVE IS MOST LIKELY TO TRACK
AT THIS POINT. GRADUALLY COOLER AIR SETTLES INTO UPR LAKES TO CLOSE
THE WEEK. SOME LK EFFECT COULD OCCUR...THOUGH THERE ARE DIFFERENCES
IN GUIDANCE ON GENERAL WIND DIRECTION. NO NEED TO STRAY FM CONSENSUS
APPROACH FOR NOW...WHICH RESULTS IN SLIGHT CHANCES OF SNOW SHOWERS
THURSDAY AND FRIDAY NEAR LAKE SUPERIOR.
&&
.AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING)
ISSUED AT 533 AM EST SAT MAR 3 2012
SAW...THIS LOCATION WL BE CLOSEST TO LO PRES MOVING NEWD THRU LOWER
MI OVERNGT. EXPECT MODERATE SN TO PERSIST THRU THE NIGHT AND RESULT
IN LIFR CONDITIONS AT TIMES...ESPECIALLY LATER TNGT WHEN INCRSG N
WINDS ON THE WRN FLANK OF THE LO PASSING TO THE E WL CAUSE SOME
BLSN. ONCE THE LO MOVES FARTHER TO THE E ON SAT...DRIER AIR WL
ARRIVE AND THE WINDS WL SLOWLY DIMINISH...SO CONDITIONS WL IMPROVE
TO MVFR.
CMX/IWD...ALTHOUGH THESE LOCATIONS ARE FARTHER W OF THE LO TRACK...
STRENGTHENING CYC NNE FLOW THRU THE NGT WL CAUSE SOME -SN AND
IFR/OCNL MVFR CONDITIONS. THE ARRIVAL OF DRIER AIR/WEAKENING CYC
FLOW BY SAT AFTN WL CAUSE CONDITIONS TO IMPROVE TO MVFR.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 533 AM EST SAT MAR 3 2012
ONCE RIDGE SLIDES OUT TO THE EAST A STRONGER LOW PRESSURE IS FCST TO
MOVE ACROSS SOUTHERN TIER OF CANADA. TIGHTER PRESSURE GRADIENT BTWN
THE RIDGE AND THE APPROACHING LOW MAY LEAD TO 30 KT SOUTHERLY WINDS
OVR EAST HALF OF LK SUPERIOR TUESDAY NIGHT INTO WEDNESDAY. STABILITY
IS HIGH...BUT IF PRESSURE FALLS NORTH OF LK SUPERIOR ARE STRONG
ENOUGH...COULD SEE GALE GUSTS OVR EASTERN LK SUPERIOR. COLD FRONT
WORKS ACROSS ON WEDNESDAY. NORTHWEST TO NORTHERLY WINDS IN WAKE OF
THE FRONT ARE EXPECTED TO REMAIN BLO 25 KTS THURSDAY INTO FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WARNING UNTIL 7 PM EST THIS EVENING FOR MIZ013-014.
WINTER STORM WARNING UNTIL 1 AM EST SUNDAY FOR MIZ007.
WINTER WEATHER ADVISORY UNTIL 6 AM CST EARLY THIS MORNING FOR
MIZ012.
WINTER STORM WARNING UNTIL 7 AM EST SUNDAY FOR MIZ005-006-085.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 4 AM EST SUNDAY FOR
LSZ243>245-248>251-263>267.
GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LSZ244-245-248>251-
264>267.
GALE WARNING UNTIL 1 PM EST THIS AFTERNOON FOR LSZ263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...KC
MARINE...JLA
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1000 AM CST Sat Mar 3 2012
.UPDATE...
/949 AM CST Sat Mar 3 2012/
Water vapor imagery shows a fairly well pronounced PV anomaly moving
south from Northern Plains along the eastern edge of a building ridge
and enhancing the troughing already digging into the central CONUS.
This anomaly will bring cooler air aloft and with surface
temperatures expected to climb into the upper 40s to lower 50s, steep
lapse rates should result. Indeed, modified afternoon soundings yield
a small amount of instability which may be enough get a few showers
going given the enhanced lift with the approaching upper PV anomaly.
However, dry low levels should keep much of the precipitation as
virga so for now have only added a chance for few sprinkles to mainly
just our Kansas zones. The latest NAM, HRRR and 00Z NSSL WRF and
NCEP WRF all develop some showers this afternoon ahead of this
feature from Nebraska into eastern Kansas and have apparently keyed
on the lift and weak instability generated from the approaching upper
wave.
CDB
&&
.DISCUSSION...
The main focus of the forecast will surround a small chance for
precipitation tomorrow and then the upcoming warming trend this week.
Upper level trough responsible for the severe weather outbreak
across the Ohio and Tennessee valleys and into the SE US yesterday
continues to churn across the Great Lakes early this morning. Wrap
around stratus on the back side of the system slowly edging
southward across the bulk of Iowa. Expect some of this cloud cover
to make it into the northern and eastern counties during the day,
which may tend to hold temperatures on the cool side across these
locations. Elsewhere, downslope component to the low level wind
fields combined with deep mixing should allow temperatures to warm
into the mid to upper 40s across the western 2/3rds of the area.
By tomorrow, northwest upper flow pattern will be in place with a
weak embedded wave expected to traverse the upper Midwest. This may
provide a slight chance for some light precipitation across the far
northeast corner of the forecast area. Morning soundings look to
support snow before low level temperatures warm by the afternoon for
more of rain profile. Expect a similar temperature gradient to be in
place again on Sunday with mid to upper 40s by the afternoon hours
across northeast Missouri and readings near the 60 degree mark across
eastern Kansas.
Surface ridge slides east of the area on Monday with southerly low
level flow returning to the region. Wind fields will further
strengthen through the beginning of the work week as pressure falls
take shape across the high plains. This will help transport much
warmer temperatures into the area and therefore continued to push
temperatures above the consensus numbers through Wednesday. Given the
deep southerly low level flow expected to be in place by Tuesday,
still thinking at least lower 70s will be possible across eastern
Kansas/western Missouri by the afternoon hours.
Models continue to advertise the next storm system to move into the
plains on Wednesday with an associated cold front to move into the
forecast area during this time frame. While differences still exists
with the timing and amplitude of this system, guidance has come into
somewhat better agreement. However given continued uncertainty,
maintained pops close to consensus numbers to account.
Deroche
&&
.AVIATION...
For the 12Z TAFs...VFR conditions will prevail through the next 24
hours. Surface wind will be rather gusty and from the northwest
through the afternoon hours, before relaxing and turning to the west
later tonight.
Cutter
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
WFO EAX
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
1242 PM EST SAT MAR 3 2012
.AVIATION...
RADAR TRENDS OVER LAST HALF HOUR OR SO INDICATING INCREASING
RETURNS AND INTENSITY ALONG THE IN/MI STATE LINE. VSBYS AT KSBN
HAVE DROPPED TO 2SM RECENTLY AND EXPECT THIS TO CONTINUE AT TIMES.
A DUSTING OF SNOW COULD IMPACT RUNWAYS AT KSBN IF BAND PERSISTS
LONG ENOUGH. TEMPO GROUP MODIFIED SLIGHTLY TO REFLECT THIS.
OTHERWISE LITTLE MORE THAN FLURRIES/LGT SNOW SHOWERS TO BE SEEN
OUTSIDE THESE BANDS.
FOCUS WILL TURN TOWARDS NEXT WAVE DROPPING IN LATER TONIGHT.
MODELS STILL ADVERTISE INCREASE IN LIFT AND LAKE EFFECT PARAMETERS
TOWARDS 12Z SUN WHEN A DECENT BAND OF SNOWSHOWERS SHOULD SET UP
FROM BERRIEN COUNTY INTO THE KSBN AREA. VSBYS AND CIGS COULD BE
IMPACTED MORE THAN IFR BUT APPEAR ON TRACK AND LEFT ALONE WITH
ONLY SLIGHT TIMING ADJUSTMENT. FURTHER TWEAKS WILL BE NEEDED WITH
LATER FORECASTS...ESPECIALLY BY THE 6Z TAF TIME WHEN BANDS SHOULD
BE UNDERWAY ACROSS MICHIGAN AND BETTER CORRELATION OF MODEL
GUIDANCE CAN BE ASCERTAINED. MVFR IMPACT AT KFWA AT THIS POINT
WITH THE OVERNIGHT FEATURES INTO SUNDAY. MODELS DO SUGGEST BAND
COULD GET CLOSE TO THE AIRPORT BUT GIVEN UNCERTANTITY OF INLAND
EXTENT WILL HOLD OFF ON ANY CHANGES.
&&
.PREV DISCUSSION... /ISSUED 1043 AM EST SAT MAR 3 2012/
UPDATE...
UPDATED GRIDS/ZONES OUT TO EXPAND POPS INTO THIS AFTERNOON ACROSS
THE NORTH WHERE UPSTREAM TRENDS SUGGEST A HIGH CONFIDENCE...LOW
QPF EVENT INTO THIS AFTERNOON. CYCLONIC FLOW AROUND THE DEPARTING
AREA OF LOW PRESSURE WAS CONTINUING TO STIR UP SNOW SHOWERS AND
FLURRIES ACROSS MUCH OF THE GREAT LAKES...EVEN BACK INTO
WISCONSIN. ONLY TALKING MAYBE A TENTH OR 2 IN MOST AREAS BUT
ENOUGH TO MAINTAIN/RAISE POPS SOMEWHAT. ALSO LOWERED TEMPS A
DEGREE OR 2 GIVEN NO SIGNS OF CLEARING AND LITTLE OVERALL SWING IN
TEMPS EXPECTED.
MARINE...
GALE WARNING WAS DOWNGRADED TO SMALL CRAFT ADVISORY EARLIER WITH
WIND GUSTS AT BOTH MICHIGAN CITY AND ST JOE MARINE SITES HOLDING
BELOW 35 KNOTS FOR PAST COUPLE OF HOURS. WAVES WILL CONTINUE HIGH
INTO TONIGHT.
PREV DISCUSSION... /ISSUED 652 AM EST SAT MAR 3 2012/
SHORT TERM...
TODAY THROUGH SUNDAY NIGHT.
FAVOR RUC/NAM WRT SHORTWAVE TIMING AND RUC BEST HANDLE ON
SATURATION BLO 925MB SUBSIDENCE INVERSION THIS AM. DIFFICULT FCST
IN NW FLOW/EMBEDDED SHORTWAVES/VARYING DEGREES OF LAKE ENHANCEMENT
THROUGH SHORT TERM...THOUGH ON WHOLE RELATIVELY BENIGN. VIGOROUS
SHORTWAVE CONTINUES TO LIFT NEWD INTO ONT/QUEB THIS AM...TAKING
LEAD AS MN WAVE UNDERGOES STRETCHING AS IT DIVES SEWD TOWARD CWA
THIS AM. BACKING CBL FLOW IN ADVANCE OF THIS WAVE SHOULD KEEP LAKE
ENHANCED RETURNS RELEGATED TO NRN BERRIEN/CASS COUNTIES. WEAK
UPSTREAM RETURNS AHEAD OF SHORTWAVE SHOULD MAINTAIN AMID CONTD
925-850MB COLD ADVECTION/DCVA REGIME ACRS NRN IN/SWRN LWR MI.
ACCUMS IN CHECK TODAY PER WARM BL AND SOIL SFCS...GNRLY NO
APPRECIABLE ACCUMS EXPECTED... SAVE FOR UP TO AN INCH TODAY IN FAR
NRN TIER BERRIEN TO CASS COUNTIES MI. STRONGER SHORTWAVE POISED
ACRS FAR NRN CANADA TO DIVE SEWD ALONG NRN PERIPHERY OF EPAC RIDGE
PRIOR TO ITS COLLAPSE DY2. INCRS SATURATION/AND LIFT WITHIN DGZ AS
LAKE INDUCED EQL RISE TO 9-10KFT BY DAYBREAK SUNDAY IN 295-300
DEGREE MEAN CBL FLOW WARRANTS RISE IN POPS DOWNWIND LK MI THROUGH
TONIGHT. WEAK FLOW SHOULD LIMIT IN LAND EXTENT. YET ANOTHER WAVE
NEAR YELLOWKNIFE AND ASSOCD MIDLVL JET STREAK FOR SUNDAY. DEEP UVM
AIDED ACRS CWA IN LEFT FRONT QUAD REGN OF 140-150KT UL JET TO DIVE
SE THROUGH NRN PLAINS TO MO/IL...SHARPENING MIDLVL TROF AND
FOCUSING INVERTED SFC TROFFING FM NRN MN-SERN WI SEWD THROUGH
HEART OF CWA FOR SYNOPTIC SWATCH OF ENHANCED SNOWFALL
SUNDAY...WITH FOCUSED POPS ALONG ATYPICAL NW FLOW PATTERN
DEPICTING I280K WEAK UPGLIDE. OVERALL HIGH DIFFICULTY IN
PLACEMENT/TIMING...HOWEVER DID AFFORD SOME NW TO SE TIMING OF HIR
POPS SUN AS SHORTWAVE INFLUENCE DWINDLES ACRS NWRN CWA SUNDAY AFTN
AS ENERGY TRANSFER AIDS UPTICK IN MID ATL/COASTAL CYCLOGENESIS.
TEMPS TYPICALLY AOB GUID WITH EXPANSIVE CLOUD COVER TODAY/WEAK CAA
AND ANTICIPATED HIGH PROB/LOW QPF SNOWBAND SUN.
LONG TERM...
MONDAY THROUGH FRIDAY...THE MAIN CHALLENGES THIS PERIOD OCCUR LATE
NEXT WEEK WHEN ANOTHER UPPER LEVEL SYSTEM MOVES INTO THE AREA.
OVERALL...THE GFS...ECMWF AND CANADIAN GEM ENSEMBLE SPREADS WERE
VERY LARGE...ESPECIALLY THE ECMWF WHERE NORMALIZED STANDARD
DEVIATIONS WERE LARGE AND INDICATED LOW CONFIDENCE. THEREFORE...MADE
VERY FEW CHANGES AFTER TUESDAY NIGHT. THE ONGOING FORECAST WITH A
CHANCE FOR RAIN WEDNESDAY THROUGH THURSDAY IS STILL PLAUSIBLE AND IS
SUPPORTED BY THE OPERATIONAL GFS RUN. OTHERWISE...KEPT MONDAY COLD
FOLLOWED BY MODERATING TEMPERATURES TUESDAY AND WEDNESDAY. CONTINUED
TO TREND DOWN LOWS MONDAY NIGHT...ESPECIALLY OVER EAST AREAS AS A
COLD SFC HIGH LINGERS OVER THE AREA.
&&
.IWX WATCHES/WARNINGS/ADVISORIES...
IN...NONE.
MI...NONE.
OH...NONE.
LM...SMALL CRAFT ADVISORY UNTIL 5 AM EST SUNDAY FOR LMZ043-046.
&&
$$
SHORT TERM...MURPHY
LONG TERM...SKIPPER
AVIATION...FISHER
UPDATE...FISHER
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
455 PM EST SAT MAR 3 2012
.SYNOPSIS...
COLDER AIR WILL FILTER INTO THE AREA TONIGHT AND SUNDAY WITH SNOW
SHOWERS POSSIBLE ACROSS THE AREA. A CLIPPER SYSTEM WILL PASS
SOUTH OF THE AREA SUNDAY NIGHT INTO MONDAY WITH TRAILING HIGH
PRESSURE ALLOWING FOR A DRY MID-WEEK.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
MADE A QUICK UPDATE TO ADD THE WORDING FOR ISOLATED FLURRIES A BIT
FURTHER SOUTH. OTHERWISE NO OTHER CHANGES.
PREVIOUS DISCUSSION FOLLOWS...
THE LATEST RUC MID-LEVEL ANALYSIS INDICATES A CLOSED 500MB LOW
ACROSS QUEBEC WITH A SOUTHWESTERLY FLOW SOUTH OF THIS FEATURE
ACROSS THE UPPER OHIO VALLEY. 1000-800MB LAYER MOISTURE IS
ADVECTING IN FROM THE WEST WITH MOSTLY CLOUDY SKIES WEST OF A
LATROBE-MORGANTOWN LINE. AT THE SURFACE, A 982MB LOW IS LOCATED IN
QUEBEC WITH A COLD FRONT EXTENDING SOUTH OF THIS FEATURE ALONG THE
EAST COAST OF THE US. A FEW FLURRIES ARE PASSING NORTH OF THE
PITTSBURGH METRO AS WEAK MID-LEVEL VORT ENERGY SLIDES ACROSS THE
AREA. A TIGHT PRESSURE GRADIENT IS IN PLACE BETWEEN THE LOW AND A
HIGH ACROSS THE PLAINS HAS ALLOWED FOR WINDS GUSTING AT 30 TO 40
MPH.
TONIGHT...WINDS WILL SUBSIDE WITH THE LOSS OF DIURNAL HEATING.
THE LOW-LEVEL FLOW WILL SHIFT FROM WESTERLY TO WEST-
NORTHWESTERLY, WITH THE CHANCE OF SNOW SHOWERS RETURNING ALONG THE
I-80 CORRIDOR BY 06Z SUNDAY. LITTLE OR NO SNOW ACCUMULATION IS
EXPECTED THROUGH DAWN. LOW TEMPS ARE A MAV/MET BLEND, NEAR
SEASONAL NORMALS TONIGHT.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
THERE IS OPERATIONAL MODEL AGREEMENT THAT THE LOW-LEVEL FLOW WILL
SHIFT FROM WEST-NORTHWESTERLY TO NORTHWESTERLY DURING THE DAY ON
SUNDAY. 850MB TEMPS WILL COOL TO -11C TO -13C ACROSS THE NORTH AND
INVERSION HEIGHTS WILL BE ABOVE 7KFT WITH THE BEST TIME FOR
ACCUMULATION FOR LAKE EFFECT BEING SUNDAY MORNING. INVERSION
HEIGHTS LOWER INTO THE AFTERNOON AND WILL LIMIT LAKE EFFECT
ACCUMULATION. THE FLOW WILL GET MORE OF A NORTHERLY COMPONENT TO IT
AS THE NEXT COLD FRONT MOVES IN. WITH THE FRONT, THE NAM 4KM
SIMULATED RADAR INDICATES A BAND SLIDING SOUTHWARD ACROSS THE
AREA. THIS IS HIGHLIGHTED WITH LIKELY POPS FOR SUNDAY AFTERNOON
INTO THE EVENING. ACCUMULATIONS SUNDAY WILL AMOUNT TO 1 TO 2
INCHES ACROSS THE LAKE EFFECT ZONES AND EASTERN RIDGES WITH
GENERALLY AN INCH OR LESS ELSEWHERE. WITH COLD AIR ADVECTION
ONGOING THROUGHOUT THE DAY, HIGHS WILL BE AROUND 5 TO 10 DEGREES
BELOW NORMAL.
SUNDAY NIGHT THROUGH TUESDAY...UNCERTAINTY ENTERS THE FORECAST
AS A THE FRONT SLIDES SOUTH OF THE AREA AND A CLIPPER PASSES
SOUTH OF THE AREA EARLY ON MONDAY. MID-LEVEL TROUGH CROSSING THE
AREA MAY PROVIDE FORCING FOR SNOW SHOWERS ON MONDAY, ALTHOUGH HAVE
LIMITED POPS TO CHANCE POPS ACROSS THE SOUTH WITH SCHC NORTHWARD.
FOLLOWING THIS SYSTEM, A MID-LEVEL RIDGE AND SURFACE HIGH PRESSURE
WILL ALLOW FOR A DRY FORECAST MONDAY NIGHT THROUGH TUESDAY.
TEMPERATURES WILL REMAIN 5 TO 10 DEGREES BELOW NORMAL AS HIGH
PRESSURE REINFORCES THE ARCTIC AIR MASS ON MONDAY. WARMING 850
TEMPS AND ABUNDANT SUNSHINE WILL ALLOW TEMPS TO RECOVER QUICKLY ON
TUESDAY, WARMING TO AROUND 5 DEGREES ABOVE NORMAL.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
HIGH PRESSURE OFF THE EAST COAST WILL PUSH FARTHER OFFSHORE
WEDNESDAY. LATEST MODEL RUNS SHOW COLD FRONT ARRIVING FROM THE
PLAINS SLIGHTLY LATER THAN YESTERDAYS RUNS...AND HAVE KEPT SLIGHT
CHANCE POPS IN FOR PITTSBURGH SOUTH AND EAST THURSDAY. 12Z GFS HAS
COME MORE IN LINE WITH OTHER GUIDANCE...WITH A NORTH-SOUTH
ORIENTATION AND THE FRONT MAKING SLOW PROGRESS. WITH THE SLOW PACE
OF THE FRONT...HAVE GONE WITH CHANCE POPS EVERYWHERE THURSDAY NIGHT
THROUGH FRIDAY NIGHT. LITTLE MODEL AGREEMENT ON SATURDAY...AND HAVE
JUST GONE WITH SLIGHT CHANCE POPS. TEMPS WILL BE ABOVE NORMAL
WEDNESDAY AND THURSDAY AHEAD OF THE FRONT...WITH A DECREASE TOWARDS
NORMAL TEMPERATURES ON FRIDAY AND SATURDAY.
&&
.AVIATION /22Z SATURDAY THROUGH THURSDAY/...
OVERCAST SKIES WILL SLOWLY OVERTAKE DUJ...LBE...AND MGW THIS
AFTERNOON. ALL SITES WILL BE OVERCAST WITH LOW VFR CIGS. SOME LIGHT
PRECIPITATION HAS BEEN REPORTED AT YNG AND UCP...BUT DO NOT THINK
THIS WILL MAKE IT TO ANY TAF SITES. AFTER SUNSET...VFR CIGS WILL
SLIGHTLY RISE FOR THE OVERNIGHT HOURS. W-SW WINDS WILL BE THE
BIGGEST AVIATION CONCERN THROUGH THE AFTERNOON...WITH WIDESPREAD 30
KT GUSTS. MGW WILL LIKELY HAVE LIGHTER WIND GUSTS...AROUND 25
KTS...WITH FKL AND DUJ CLOSER TO 35 KTS. WINDS WILL DROP TO 10-12
KTS SHORTLY AFTER SUNSET. UPPER LEVEL SYSTEM ARRIVING SUNDAY MORNING
WILL BRING MVFR CIGS AND LIGHT SNOW SHOWERS. AT THIS POINT...DO NOT
EXPECT ANY IFR VISIBILITIES THROUGH THE TAF PERIOD.
OUTLOOK...SUNDAY THROUGH THURSDAY...
IFR WEATHER IS POSSIBLE PRIMARILY AT FKL AND DUJ SUNDAY AFTERNOON IN
SNOW SHOWERS...BUT CANNOT RULE OUT IFR AT OTHER SITES THROUGH THE
AFTERNOON AND EVENING HOURS. AS HIGH PRESSURE MOVES IN
MONDAY...EXPECT VFR CONDITIONS THROUGH THE FIRST HALF OF THE WEEK. A
COLD FRONT COULD BRING RESTRICTIONS IN RAIN SHOWERS THURSDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
338 PM EST SAT MAR 3 2012
.SYNOPSIS...
COLDER AIR WILL FILTER INTO THE AREA TONIGHT AND SUNDAY WITH SNOW
SHOWERS POSSIBLE ACROSS THE AREA. A CLIPPER SYSTEM WILL PASS
SOUTH OF THE AREA SUNDAY NIGHT INTO MONDAY WITH TRAILING HIGH
PRESSURE ALLOWING FOR A DRY MID-WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
THE LATEST RUC MID-LEVEL ANALYSIS INDICATES A CLOSED 500MB LOW
ACROSS QUEBEC WITH A SOUTHWESTERLY FLOW SOUTH OF THIS FEATURE
ACROSS THE UPPER OHIO VALLEY. 1000-800MB LAYER MOISTURE IS
ADVECTING IN FROM THE WEST WITH MOSTLY CLOUDY SKIES WEST OF A
LATROBE-MORGANTOWN LINE. AT THE SURFACE, A 982MB LOW IS
LOCATED IN QUEBEC WITH A COLD FRONT EXTENDING SOUTH OF THIS
FEATURE ALONG THE EAST COAST OF THE US. A FEW FLURRIES ARE PASSING
NORTH OF THE PITTSBURGH METRO AS WEAK MID-LEVEL VORT ENERGY SLIDES
ACROSS THE AREA. A TIGHT PRESSURE GRADIENT IS IN PLACE BETWEEN THE LOW
AND A HIGH ACROSS THE PLAINS HAS ALLOWED FOR WINDS GUSTING AT 30
TO 40 MPH.
TONIGHT...WINDS WILL SUBSIDE WITH THE LOSS OF DIURNAL HEATING.
THE LOW-LEVEL FLOW WILL SHIFT FROM WESTERLY TO WEST-
NORTHWESTERLY, WITH THE CHANCE OF SNOW SHOWERS RETURNING ALONG THE
I-80 CORRIDOR BY 06Z SUNDAY. LITTLE OR NO SNOW ACCUMULATION IS
EXPECTED THROUGH DAWN. LOW TEMPS ARE A MAV/MET BLEND, NEAR
SEASONAL NORMALS TONIGHT.
&&
.SHORT TERM /SUNDAY THROUGH TUESDAY/...
THERE IS OPERATIONAL MODEL AGREEMENT THAT THE LOW-LEVEL FLOW WILL
SHIFT FROM WEST-NORTHWESTERLY TO NORTHWESTERLY DURING THE DAY ON
SUNDAY. 850MB TEMPS WILL COOL TO -11C TO -13C ACROSS THE NORTH AND
INVERSION HEIGHTS WILL BE ABOVE 7KFT WITH THE BEST TIME FOR
ACCUMULATION FOR LAKE EFFECT BEING SUNDAY MORNING. INVERSION
HEIGHTS LOWER INTO THE AFTERNOON AND WILL LIMIT LAKE EFFECT
ACCUMULATION. THE FLOW WILL GET MORE OF A NORTHERLY COMPONENT TO IT
AS THE NEXT COLD FRONT MOVES IN. WITH THE FRONT, THE NAM 4KM
SIMULATED RADAR INDICATES A BAND SLIDING SOUTHWARD ACROSS THE
AREA. THIS IS HIGHLIGHTED WITH LIKELY POPS FOR SUNDAY AFTERNOON
INTO THE EVENING. ACCUMULATIONS SUNDAY WILL AMOUNT TO 1 TO 2
INCHES ACROSS THE LAKE EFFECT ZONES AND EASTERN RIDGES WITH
GENERALLY AN INCH OR LESS ELSEWHERE. WITH COLD AIR ADVECTION
ONGOING THROUGHOUT THE DAY, HIGHS WILL BE AROUND 5 TO 10 DEGREES
BELOW NORMAL.
SUNDAY NIGHT THROUGH TUESDAY...UNCERTAINTY ENTERS THE FORECAST
AS A THE FRONT SLIDES SOUTH OF THE AREA AND A CLIPPER PASSES
SOUTH OF THE AREA EARLY ON MONDAY. MID-LEVEL TROUGH CROSSING THE
AREA MAY PROVIDE FORCING FOR SNOW SHOWERS ON MONDAY, ALTHOUGH HAVE
LIMITED POPS TO CHANCE POPS ACROSS THE SOUTH WITH SCHC NORTHWARD.
FOLLOWING THIS SYSTEM, A MID-LEVEL RIDGE AND SURFACE HIGH PRESSURE
WILL ALLOW FOR A DRY FORECAST MONDAY NIGHT THROUGH TUESDAY.
TEMPERATURES WILL REMAIN 5 TO 10 DEGREES BELOW NORMAL AS HIGH
PRESSURE REINFORCES THE ARCTIC AIR MASS ON MONDAY. WARMING 850
TEMPS AND ABUNDANT SUNSHINE WILL ALLOW TEMPS TO RECOVER QUICKLY ON
TUESDAY, WARMING TO AROUND 5 DEGREES ABOVE NORMAL.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
HIGH PRESSURE OFF THE EAST COAST WILL PUSH FARTHER OFFSHORE
WEDNESDAY. LATEST MODEL RUNS SHOW COLD FRONT ARRIVING FROM THE
PLAINS SLIGHTLY LATER THAN YESTERDAYS RUNS...AND HAVE KEPT SLIGHT
CHANCE POPS IN FOR PITTSBURGH SOUTH AND EAST THURSDAY. 12Z GFS HAS
COME MORE IN LINE WITH OTHER GUIDANCE...WITH A NORTH-SOUTH
ORIENTATION AND THE FRONT MAKING SLOW PROGRESS. WITH THE SLOW PACE
OF THE FRONT...HAVE GONE WITH CHANCE POPS EVERYWHERE THURSDAY NIGHT
THROUGH FRIDAY NIGHT. LITTLE MODEL AGREEMENT ON SATURDAY...AND HAVE
JUST GONE WITH SLIGHT CHANCE POPS. TEMPS WILL BE ABOVE NORMAL
WEDNESDAY AND THURSDAY AHEAD OF THE FRONT...WITH A DECREASE TOWARDS
NORMAL TEMPERATURES ON FRIDAY AND SATURDAY.
&&
.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
OVERCAST SKIES WILL SLOWLY OVERTAKE DUJ...LBE...AND MGW THIS
AFTERNOON. ALL SITES WILL BE OVERCAST WITH LOW VFR CIGS. SOME LIGHT
PRECIPITATION HAS BEEN REPORTED AT YNG AND UCP...BUT DO NOT THINK
THIS WILL MAKE IT TO ANY TAF SITES. AFTER SUNSET...VFR CIGS WILL
SLIGHTLY RISE FOR THE OVERNIGHT HOURS. W-SW WINDS WILL BE THE
BIGGEST AVIATION CONCERN THROUGH THE AFTERNOON...WITH WIDESPREAD 30
KT GUSTS. MGW WILL LIKELY HAVE LIGHTER WIND GUSTS...AROUND 25
KTS...WITH FKL AND DUJ CLOSER TO 35 KTS. WINDS WILL DROP TO 10-12
KTS SHORTLY AFTER SUNSET. UPPER LEVEL SYSTEM ARRIVING SUNDAY MORNING
WILL BRING MVFR CIGS AND LIGHT SNOW SHOWERS. AT THIS POINT...DO NOT
EXPECT ANY IFR VISIBILITIES THROUGH THE TAF PERIOD.
OUTLOOK...SUNDAY THROUGH THURSDAY...
IFR WEATHER IS POSSIBLE PRIMARILY AT FKL AND DUJ SUNDAY AFTERNOON IN
SNOW SHOWERS...BUT CANNOT RULE OUT IFR AT OTHER SITES THROUGH THE
AFTERNOON AND EVENING HOURS. AS HIGH PRESSURE MOVES IN
MONDAY...EXPECT VFR CONDITIONS THROUGH THE FIRST HALF OF THE WEEK. A
COLD FRONT COULD BRING RESTRICTIONS IN RAIN SHOWERS THURSDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
119 PM EST SAT MAR 3 2012
.SYNOPSIS...
STRONG WINDS BEHIND A COLD FRONT WILL USHER IN COLDER AIR TONIGHT
AND SUNDAY. A COLD WEST-NORTHWESTERLY FLOW OFF OF THE LAKES WILL
ALLOW FOR SNOW SHOWERS ACROSS THE AREA TONIGHT INTO SUNDAY. A
CLIPPER SYSTEM WILL PASS SOUTH OF THE AREA SUNDAY NIGHT INTO
MONDAY WITH TRAILING HIGH PRESSURE ALLOWING FOR A DRY MID-WEEK.
&&
.NEAR TERM /THROUGH TONIGHT/...
A QUICK UPDATE HAS BEEN ISSUED TO CANCEL THE WIND ADVISORY AND TO
ACCOUNT FOR THE LATEST TRENDS IN TEMP AND SKY GRIDS.
THE LATEST RUC MID-LEVEL ANALYSIS INDICATES A CLOSED 500MB LOW
ACROSS QUEBEC WITH A SOUTHWESTERLY FLOW SOUTH OF THIS FEATURE ACROSS
THE UPPER OHIO VALLEY. 1000-800MB LAYER MOISTURE IS ADVECTING IN
FROM THE WEST WITH MOSTLY CLOUDY SKIES WEST OF A LATROBE-
NEW MARTINSVILLE LINE. AT THE SURFACE, A 982MB LOW IS LOCATED IN
QUEBEC WITH A COLD FRONT EXTENDING SOUTH OF THIS FEATURE ALONG
THE EAST COAST OF THE US. A TIGHT PRESSURE GRADIENT IS IN PLACE
BETWEEN THE LOW AND A HIGH ACROSS THE PLAINS HAS ALLOWED FOR WINDS
GUSTING AT 30 TO 40 MPH.
THIS AFTERNOON...LOW-LEVEL MOISTURE WILL CONTINUE TO ADVECT INTO
THE AREA WITH CLOUD COVERAGE INCREASING FROM THE WEST. BUFKIT DIURNAL
MIXING SUPPORTS WIND GUSTS CONTINUING TO GUST AT 30 TO 40
MPH. THUS, THE WIND ADVISORY HAS BEEN CANCELLED. WITH MOSTLY SUNNY
SKIES EARLY TODAY, TEMPS HAVE BEEN INCREASED A FEW DEGREES ACROSS
NORTH-CENTRAL WV.
TONIGHT...WINDS WILL SUBSIDE WITH THE LOSS OF DAYTIME HEATING.
THE LOW-LEVEL FLOW WILL SHIFT FROM WESTERLY TO WEST-
NORTHWESTERLY, WITH THE CHANCE OF SNOW SHOWERS RETURNING ALONG THE
I-80 CORRIDOR BY 06Z SUNDAY. LITTLE OR NO SNOW ACCUMULATION IS
EXPECTED THROUGH DAWN. LOW TEMPS ARE A MAV/MET BLEND, NEAR
SEASONAL NORMALS TONIGHT.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
A COLD WEST-NORTHWESTERLY FLOW WITH 850 TEMPS AT -12C TO -14C WILL
ALLOW FOR LAKE EFFECT SNOW SHOWERS TO CONTINUE. LIKELY POPS ARE
FORECAST ALONG THE I-80 CORRIDOR AND EASTERN RIDGES WITH CHANCE
POPS ELSEWHERE. AN ASSOCIATED TROF REFLECTED AT BOTH 850 AND THE
SURFACE SHOULD HELP ENHANCED SNOW SHOWERS SOMEWHAT. FETCH OFF OF
THE LAKES WILL EVENTUALLY CUT OFF AS 850 RIDGE APPROACHES ON
MONDAY. SEVERAL INCHES POSSIBLE I80 AND NORTH AND
MOUNTAINS...ELSEWHERE LIGHT AMOUNTS. HIGH PRESSURE THEN BUILDS
INTO AREA.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
HIGH PRESSURE WILL DOMINATE THE REGION THROUGH THURSDAY. SOUTHWEST
FLOW TO INCREASE WEDNESDAY INTO THURSDAY WITH INCREASE IN WINDS.
PROBABLY GUSTY ESPECIALLY IN THE AFTERNOON. NEXT FRONT APPROACHES EARLY
THURSDAY WITH CHANCE SHOWERS. DISCREPANCY BETWEEN ECMWF AND GFS ON
HANDLING NEXT FRONT. GFS BRINGS IN PRECIPITATION THURSDAY MORNING
AND EVENTUALLY LAYS FRONT OUT EAST TO WEST AND HANGS ACROSS
SOUTHERN PORTION AREA BEFORE HIGH BUILDS IN ON SATURDAY.
MEANWHILE, ECMWF HAS SLOWER EASTWARD PROGRESSION WITH APPROACH TO
CWA ON FRIDAY AND KEEPS SHOWERS IN THROUGH THE DAY WITH SLOWER
EXIT AND RETARDS SURFACE RIDGE BUILDING INTO AREA.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
OVERCAST SKIES WILL SLOWLY OVERTAKE DUJ...LBE...AND MGW THIS
AFTERNOON. ALL SITES WILL BE OVERCAST WITH LOW VFR CIGS. SOME LIGHT
PRECIPITATION HAS BEEN REPORTED AT YNG AND UCP...BUT DO NOT THINK
THIS WILL MAKE IT TO ANY TAF SITES. AFTER SUNSET...VFR CIGS WILL
SLIGHTLY RISE FOR THE OVERNIGHT HOURS. W-SW WINDS WILL BE THE
BIGGEST AVIATION CONCERN THROUGH THE AFTERNOON...WITH WIDESPREAD 30
KT GUSTS. MGW WILL LIKELY HAVE LIGHTER WIND GUSTS...AROUND 25
KTS...WITH FKL AND DUJ CLOSER TO 35 KTS. WINDS WILL DROP TO 10-12
KTS SHORTLY AFTER SUNSET. UPPER LEVEL SYSTEM ARRIVING SUNDAY MORNING
WILL BRING MVFR CIGS AND LIGHT SNOW SHOWERS. AT THIS POINT...DO NOT
EXPECT ANY IFR VISIBILITIES THROUGH THE TAF PERIOD.
OUTLOOK...SUNDAY THROUGH THURSDAY...
IFR WEATHER IS POSSIBLE PRIMARILY AT FKL AND DUJ SUNDAY AFTERNOON IN
SNOW SHOWERS...BUT CANNOT RULE OUT IFR AT OTHER SITES THROUGH THE
AFTERNOON AND EVENING HOURS. AS HIGH PRESSURE MOVES IN
MONDAY...EXPECT VFR CONDITIONS THROUGH THE FIRST HALF OF THE WEEK. A
COLD FRONT COULD BRING RESTRICTIONS IN RAIN SHOWERS THURSDAY.
&&
.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
OH...NONE.
PA...NONE.
WV...NONE.
&&
$$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1226 PM EST SAT MAR 3 2012
.UPDATE...
ISSUED AT 1225 PM EST SAT MAR 3 2012
HAD TO PUT OUT A LAKE EFFECT SNOW ADVISORY FOR KEWEENAW...NORTHERN
HOUGHTON AND BARAGA COUNTIES AS HEAVIER SNOW TOTALS HAVE STARTED TO
COME IN WITH CLOSE TO 6 INCHES IN L`ANSE AND 5 INCHES IN MOHAWK.
WITH FAVORABLE NORTH WIND CONTINUING...MODERATE TO HEAVY SNOW WILL
PERSIST THROUGH TONIGHT WITH THE LAKE EFFECT SNOW. RADAR TRENDS ARE
SHOWING THE SNOW LETTING UP...SO DID NOT OPT TO GO WITH A WARNING
FOR THAT AREA.
&&
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 533 AM EST SAT MAR 3 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A TROUGH DOMINATING THE CNTRL
CONUS. A POTENT MID/UPPER LEVEL LOW WAS LOCATED OVER NRN LAKE HURON.
THE STRONG FGEN/DEFORMATION ASSOCIATED WITH THIS FEATURE WAS QUICKLY
SLIDING TO THE EAST THROUGH NRN LAKE HURON. HOWEVER A LARGE SHIELD
OF PCPN ASSOCIATED WITH 285K-295 ISENTROPIC ASCENT AND 700-300 MB
QVECTOR CONV CONTINUED ACROSS LAKE SUPERIOR AND UPPER MICHIGAN.
RADAR ALSO SHOWED HIGHER RETURNS INTO N CNTRL UPPER MICHIGAN WHERE
NRLY FLOW UPSLOPE AND LAKE ENHANCEMENT (850 MB TEMPS AROUND -8C)
HAVE BOOSTED SNOWFALL RATES. AT THE SFC...A 979 MB LOW WAS LOCATED
OVER GEORGIAN BAY SUPPORTED STRONG NRLY WINDS ACROSS LAKE SUPERIOR
INTO UPPER MICHIGAN. SINCE THE SNOW TOTAL AT THE NWS OFFICE HAD
REACHED 5 INCHES BY 0930Z AND SIGNIFICANT ADDITIONAL AMOUNTS WERE
EXPECTED TODAY...UPGRADED THE ADVY TO A WARNING FOR MARQUETTE
COUNTY.
TODAY...EXPECT THE SYNOPTIC SCALE UPWARD MOTION AND PCPN SHIELD TO
GRADUALLY DIMINISH THIS MORNING AS THE MID LEVEL LOW SHIFTS TO THE
EAST. HOWEVER...WITH DEEP MOISTURE PERSISTING OVER THE AREA ALONG
WITH CAA DROPPING 850 MB TEMPS TO AROUND -15C BY 18Z...TRANSITION
TOWARD LAKE ENHANCED/EFFECT WILL KEEP AT LEAST MODERATE SNOWFALL
RATES GOING THIS MORNING. ADDITIONAL SNOWFALL AMOUNTS IN THE 3 TO 5
INCH RANGE WILL BE POSSIBLE TODAY...ESPECIALLY OVER THE EAST AND HIGHER
TERRAIN IN N CNTRL UPPER MI. OVER THE WEST...LIGHT LAKE
ENHANCED/EFFECT SNOW WILL ALSO CONTINUE WITH LOWER AMOUNTS IN THE 1
TO 3 INCH RANGE. TO THE SOUTH...THE SNOW SHOULD TAPER OFF THIS
MORNING WITH MAINLY JUST SCT -SHSN BY AFTERNOON. ALTHOUGH THE STRONG
925 MB WINDS OF 30-35 KTS MAY KEEP ACCUMULATING SNOW GOING INTO NE
AND ERN DELTA COUNTY...FARTHER TO THE SW NEAR ESC...ADDITIONAL
SNOWFALL SHOULD BE MINIMAL. DRIER SFC-800 MB LAYER AIR MOVING IN FROM
THE NORTH THIS AFTERNOON WILL BRING AN OVERALL DIMINISHING TREND WITH
THE LES.
TONIGHT...LES WILL CONTINUE TO DECREASE AS A RIDGE BUILDS INTO THE
REGION WITH LOW LEVEL WINDS DIMINISHING AND BECOMING MORE ACYC.
SINCE LIGHT TO OCNLY MODERATE SNOW MAY CONTINUE NORTH...ALLOWED WARNING
TO REMAIN IN PLACE. HOWEVER...IF SNOWFALL TRENDS DROP OFF ENOUGH AND
THE DRY AIR MOVES IN MORE AGGRESSIVELY...THE WARNINGS OVER THE NORTH
MAY BE DROPPED EARLY.
SUNDAY...ANY REMAINING N TO NE FLOW LIGHT LES SHOULD DIMINISH SUNDAY
MORNING AS INVERSION HEIGHTS DROP TO AROUND 3K FT AND LOW LEVEL WIND
FIELDS BECOME WEAK AND DISORGANIZED.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 533 AM EST SAT MAR 3 2012
GOOD AGREEMENT FM THE MEDIUM RANGE MODELS IN LARGE SCALE PATTERN
LATER THIS WEEKEND THROUGH MUCH OF THE UPCOMING WORK WEEK. COLD
TROUGH STICKS AROUND INITIALLY THROUGH SUNDAY. LIGHT NORTHERLY WINDS
AND SUFFICIENTLY COLD AIR IN LOW-LEVELS SHOULD KEEP SCATTERED LIGHT
LAKE EFFECT SNOW SHOWERS/FLURRIES GOING ALONG MUCH OF LK SUPERIOR.
DESPITE H85 TEMPS AS LOW AS -16C...ACCUMS SHOULD END UP QUITE LIGHT
AS LOW LEVEL WINDS ARE WEAK AND ANTICYCLONIC. HEADING INTO MONDAY
THE SFC RIDGE OVR ONTARIO FOR MUCH OF THE WEEKEND SETTLES INTO THE
CNTRL AND LOWER GREAT LAKES. RIDGE MOVING EAST AND TROUGH PUSHING
ACROSS SCNTRL CANADA ALLOWS BLYR WINDS TO BECOME MORE SWRLY AND
FLOW OFF LAKE SUPERIOR TO END. INDICATIONS THAT PLENTY OF CLOUDS MAY
REMAIN TRAPPED BENEATH DEVELOPING WARM AIR ADVECTION PATTERN. KEPT
SKIES PARTLY TO MOSTLY CLOUDY WITH WARMER TEMPERATURES TOWARD THE
UPR 20S/LOWER 30S.
FOR THE EXTENDED...
WARM AIR ADVECTION REGIME CONTINUES TUESDAY INTO WEDNESDAY. EARLY ON
AS STRONGER SFC LOW SLIDES ACROSS SOUTHERN TIER OF CANADA THERE
COULD BE SOME LGT SNOW TRY TO BREAK OUT OVR PORTIONS OF CWA. ECMWF
AND CANADIAN FARTHER SOUTH WITH THE SNOW WHILE GFS/NAM KEEP MAJORITY
OF SNOW OVR LK SUPERIOR AND INTO ONTARIO. MIDDLE ROAD APPROACH FOR
NOW GIVEN STRENGTH OF WARM AIR ADVECTION AND LOOK OF GFS/ECMWF LOWER
H85 DWPNT DEPRESSIONS. BETTER CHANCE OF LGT SNOW OVR THE CWA WOULD
BE MONDAY EVENING ON THE KEWEENAW AND LATER AT NIGHT OVR THE FAR
NORTHEAST CWA. WENT FOR MORE CLOUDS THAN GUIDANCE INTO TUESDAY
WITH SOUNDINGS SHOWING LOW-LEVEL MOISTURE BENEATH THE STRENGTHENING
INVERSION /H85 TEMPS PUSHING TOWARD +5C ON TUESDAY/. HIGHS ON
TUESDAY WILL BE WARM BUT COULD BE TEMPERED A BIT BY THE CLOUDS.
EVEN SO...A SHALLOW MIXING HEIGHT OF ONLY 950MB YIELDS HIGHS OVR
40 DEGREES. LEANED MORE TOWARD PREVIOUS FCST WITH MID 40S ALONG LK
SUPERIOR SHORE NW AND NCNTRL GIVEN SW WIND DIRECTION. IF WE DO SEE
SUNSHINE...HIGHER SUN ANGLE AND DENSELY FORESTED LANDSCAPE/LOWER
ALBEDO WOULD OFFSET RECENT SNOWFALL AND COULD ALLOW FOR ISOLD 50
DEGREE READINGS. SFC DWPNTS INTO THE MID 30S AND MAYBE EVEN HIGHER
FCST TO SURGE INTO UPR LAKES LATER TUESDAY INTO TUESDAY NIGHT. HAVE
ADDED FOG TO FCST MAINLY OVER INLAND AREAS WHERE TEMPS COULD DIP THE
LOWEST. AT THE LEAST...SEEMS LIKE GOOD SETUP FOR PLENTY OF STRATUS.
INCREASING SOUTHERLY WINDS WILL ALSO BE ISSUE FOR LATER TUESDAY INTO
TUESDAY NIGHT. VERY STABLE PROFILE IN LOW-LEVELS BUT EVEN SFC-BLYR
WINDS OFF MODELS POINT TO SOUTH TO SOUTHWEST WINDS NEAR GREAT LAKE
SHORES GUSTING TO 30-35 MPH ON TUESDAY NIGHT INTO WEDNESDAY MORNING.
MODELS CONTINUE TO SHOW COLD FRONT WORKING THROUGH UPR LAKES ON
WEDNESDAY AND NOW IT SEEMS LIKE TREND IS QUICKER IN BRINGING COLDER
AIR INTO WESTERN CWA. GFS SOUNDINGS AT IWD/CMX ARE ESSENTIALLY BLO
0C AS EARLY AS MID MORNING ON WEDNESDAY AND ECMWF LENDS SUPPORT TO
COLDER SCENARIO AS WELL. KEPT MIX OF RAIN/SNOW FOR CNTRL AND EAST...
BUT WENT WITH MAINLY SNOW IN THE WEST. MODEL CONSENSUS WOULD POINT
TO ADVY SNOW ACCUMS IN SOME AREAS OF THE WEST AND CENTRAL...BUT
HIGHER CERTAINTY IN THIS IDEA NOT THERE QUITE YET AS MODELS HAVE
BEEN JUMPING AROUND WITH EXTENT OF UPR WAVE LIFTING ALONG FRONT ON
WEDNESDAY AND HOW FAR WEST TO HAVE THIS WAVE. DO HAVE LIKELY POPS
NOW OVR THE EAST HALF OF THE CWA WHERE WAVE IS MOST LIKELY TO TRACK
AT THIS POINT. GRADUALLY COOLER AIR SETTLES INTO UPR LAKES TO CLOSE
THE WEEK. SOME LK EFFECT COULD OCCUR...THOUGH THERE ARE DIFFERENCES
IN GUIDANCE ON GENERAL WIND DIRECTION. NO NEED TO STRAY FM CONSENSUS
APPROACH FOR NOW...WHICH RESULTS IN SLIGHT CHANCES OF SNOW SHOWERS
THURSDAY AND FRIDAY NEAR LAKE SUPERIOR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1146 AM EST SAT MAR 3 2012
SAW...WITH STRONG NRLY WINDS AND COLDER AND DRIER AIR MOVING IN THIS
AFTERNOON...WINDS WILL SLOWLY DIMINISH...SO CONDITIONS WILL IMPROVE
TO MVFR LATE THIS AFTERNOON FROM IFR. SOME LIGHT LES WILL PERSIST
THROUGH THE REST OF THE PERIOD WITH MVFR CONDITIONS.
CMX/IWD...ALTHOUGH THESE LOCATIONS ARE FARTHER W OF THE DEPARTING
LOW PRESSURE SYSTEM CYCLONIC NNE FLOW WILL SUPPORT SOME -SN AND
IFR/OCNL MVFR CONDITIONS. THE ARRIVAL OF DRIER AIR AND WEAKENING
CYCLONIC FLOW LATE THIS AFTERNOON WILL CAUSE CONDITIONS TO
IMPROVE TO MVFR.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 533 AM EST SAT MAR 3 2012
NORTH GALES WILL CONTINUE TODAY AS LAKE SUPERIOR IS ON NORTHWEST
FRINGE OF STRONG LOW PRESSURE SYSTEM MOVING INTO QUEBEC. GALES
DIMINISH TONIGHT INTO SUNDAY AS HIGH PRESSURE RIDGE OVER ONTARIO
SLIDES INTO THE REGION. ONCE RIDGE SLIDES OUT TO THE EAST ON MONDAY
A STRONGER LOW PRESSURE IS FCST TO MOVE ACROSS SOUTHERN TIER OF
CANADA. TIGHTER PRESSURE GRADIENT BTWN THE RIDGE AND THE APPROACHING
LOW MAY LEAD TO 30 KT SOUTHERLY WINDS OVR EAST HALF OF LK SUPERIOR
TUESDAY NIGHT INTO WEDNESDAY. STABILITY IS HIGH...BUT IF PRESSURE
FALLS NORTH OF LK SUPERIOR ARE STRONG ENOUGH...COULD SEE GALE GUSTS
OVR EASTERN LK SUPERIOR. COLD FRONT WORKS ACROSS ON WEDNESDAY.
NORTHWEST TO NORTHERLY WINDS IN WAKE OF THE FRONT ARE EXPECTED TO
REMAIN BLO 25 KTS THURSDAY INTO FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST SUNDAY FOR MIZ001-003-
004.
WINTER STORM WARNING UNTIL 7 PM EST THIS EVENING FOR MIZ013-014.
WINTER STORM WARNING UNTIL 7 AM EST SUNDAY FOR MIZ005-006-085.
WINTER STORM WARNING UNTIL 1 AM EST SUNDAY FOR MIZ007.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 4 AM EST SUNDAY FOR
LSZ243>245-248>251-263>267.
GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LSZ244-245-248>251-
264>267.
GALE WARNING UNTIL 1 PM EST THIS AFTERNOON FOR LSZ263.
LAKE MICHIGAN...
NONE.
&&
$$
UPDATE...07
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...07
MARINE...JLA
AREA FORECAST DISCUSSION...UPDATED
NWS MARQUETTE MI
1147 AM EST SAT MAR 3 2012
.SHORT TERM...(TODAY THROUGH SUNDAY)
ISSUED AT 533 AM EST SAT MAR 3 2012
WV IMAGERY AND RUC ANALYSIS INDICATED A TROUGH DOMINATING THE CNTRL
CONUS. A POTENT MID/UPPER LEVEL LOW WAS LOCATED OVER NRN LAKE HURON.
THE STRONG FGEN/DEFORMATION ASSOCIATED WITH THIS FEATURE WAS QUICKLY
SLIDING TO THE EAST THROUGH NRN LAKE HURON. HOWEVER A LARGE SHIELD
OF PCPN ASSOCIATED WITH 285K-295 ISENTROPIC ASCENT AND 700-300 MB
QVECTOR CONV CONTINUED ACROSS LAKE SUPERIOR AND UPPER MICHIGAN.
RADAR ALSO SHOWED HIGHER RETURNS INTO N CNTRL UPPER MICHIGAN WHERE
NRLY FLOW UPSLOPE AND LAKE ENHANCEMENT (850 MB TEMPS AROUND -8C)
HAVE BOOSTED SNOWFALL RATES. AT THE SFC...A 979 MB LOW WAS LOCATED
OVER GEORGIAN BAY SUPPORTED STRONG NRLY WINDS ACROSS LAKE SUPERIOR
INTO UPPER MICHIGAN. SINCE THE SNOW TOTAL AT THE NWS OFFICE HAD
REACHED 5 INCHES BY 0930Z AND SIGNIFICANT ADDITIONAL AMOUNTS WERE
EXPECTED TODAY...UPGRADED THE ADVY TO A WARNING FOR MARQUETTE
COUNTY.
TODAY...EXPECT THE SYNOPTIC SCALE UPWARD MOTION AND PCPN SHIELD TO
GRADUALLY DIMINISH THIS MORNING AS THE MID LEVEL LOW SHIFTS TO THE
EAST. HOWEVER...WITH DEEP MOISTURE PERSISTING OVER THE AREA ALONG
WITH CAA DROPPING 850 MB TEMPS TO AROUND -15C BY 18Z...TRANSITION
TOWARD LAKE ENHANCED/EFFECT WILL KEEP AT LEAST MODERATE SNOWFALL
RATES GOING THIS MORNING. ADDITIONAL SNOWFALL AMOUNTS IN THE 3 TO 5
INCH RANGE WILL BE POSSIBLE TODAY...ESPECIALLY OVER THE EAST AND HIGHER
TERRAIN IN N CNTRL UPPER MI. OVER THE WEST...LIGHT LAKE
ENHANCED/EFFECT SNOW WILL ALSO CONTINUE WITH LOWER AMOUNTS IN THE 1
TO 3 INCH RANGE. TO THE SOUTH...THE SNOW SHOULD TAPER OFF THIS
MORNING WITH MAINLY JUST SCT -SHSN BY AFTERNOON. ALTHOUGH THE STRONG
925 MB WINDS OF 30-35 KTS MAY KEEP ACCUMULATING SNOW GOING INTO NE
AND ERN DELTA COUNTY...FARTHER TO THE SW NEAR ESC...ADDITIONAL
SNOWFALL SHOULD BE MINIMAL. DRIER SFC-800 MB LAYER AIR MOVING IN FROM
THE NORTH THIS AFTERNOON WILL BRING AN OVERALL DIMINISHING TREND WITH
THE LES.
TONIGHT...LES WILL CONTINUE TO DECREASE AS A RIDGE BUILDS INTO THE
REGION WITH LOW LEVEL WINDS DIMINISHING AND BECOMING MORE ACYC.
SINCE LIGHT TO OCNLY MODERATE SNOW MAY CONTINUE NORTH...ALLOWED WARNING
TO REMAIN IN PLACE. HOWEVER...IF SNOWFALL TRENDS DROP OFF ENOUGH AND
THE DRY AIR MOVES IN MORE AGGRESSIVELY...THE WARNINGS OVER THE NORTH
MAY BE DROPPED EARLY.
SUNDAY...ANY REMAINING N TO NE FLOW LIGHT LES SHOULD DIMINISH SUNDAY
MORNING AS INVERSION HEIGHTS DROP TO AROUND 3K FT AND LOW LEVEL WIND
FIELDS BECOME WEAK AND DISORGANIZED.
.LONG TERM...(SUNDAY NIGHT THROUGH FRIDAY)
ISSUED AT 533 AM EST SAT MAR 3 2012
GOOD AGREEMENT FM THE MEDIUM RANGE MODELS IN LARGE SCALE PATTERN
LATER THIS WEEKEND THROUGH MUCH OF THE UPCOMING WORK WEEK. COLD
TROUGH STICKS AROUND INITIALLY THROUGH SUNDAY. LIGHT NORTHERLY WINDS
AND SUFFICIENTLY COLD AIR IN LOW-LEVELS SHOULD KEEP SCATTERED LIGHT
LAKE EFFECT SNOW SHOWERS/FLURRIES GOING ALONG MUCH OF LK SUPERIOR.
DESPITE H85 TEMPS AS LOW AS -16C...ACCUMS SHOULD END UP QUITE LIGHT
AS LOW LEVEL WINDS ARE WEAK AND ANTICYCLONIC. HEADING INTO MONDAY
THE SFC RIDGE OVR ONTARIO FOR MUCH OF THE WEEKEND SETTLES INTO THE
CNTRL AND LOWER GREAT LAKES. RIDGE MOVING EAST AND TROUGH PUSHING
ACROSS SCNTRL CANADA ALLOWS BLYR WINDS TO BECOME MORE SWRLY AND
FLOW OFF LAKE SUPERIOR TO END. INDICATIONS THAT PLENTY OF CLOUDS MAY
REMAIN TRAPPED BENEATH DEVELOPING WARM AIR ADVECTION PATTERN. KEPT
SKIES PARTLY TO MOSTLY CLOUDY WITH WARMER TEMPERATURES TOWARD THE
UPR 20S/LOWER 30S.
FOR THE EXTENDED...
WARM AIR ADVECTION REGIME CONTINUES TUESDAY INTO WEDNESDAY. EARLY ON
AS STRONGER SFC LOW SLIDES ACROSS SOUTHERN TIER OF CANADA THERE
COULD BE SOME LGT SNOW TRY TO BREAK OUT OVR PORTIONS OF CWA. ECMWF
AND CANADIAN FARTHER SOUTH WITH THE SNOW WHILE GFS/NAM KEEP MAJORITY
OF SNOW OVR LK SUPERIOR AND INTO ONTARIO. MIDDLE ROAD APPROACH FOR
NOW GIVEN STRENGTH OF WARM AIR ADVECTION AND LOOK OF GFS/ECMWF LOWER
H85 DWPNT DEPRESSIONS. BETTER CHANCE OF LGT SNOW OVR THE CWA WOULD
BE MONDAY EVENING ON THE KEWEENAW AND LATER AT NIGHT OVR THE FAR
NORTHEAST CWA. WENT FOR MORE CLOUDS THAN GUIDANCE INTO TUESDAY
WITH SOUNDINGS SHOWING LOW-LEVEL MOISTURE BENEATH THE STRENGTHENING
INVERSION /H85 TEMPS PUSHING TOWARD +5C ON TUESDAY/. HIGHS ON
TUESDAY WILL BE WARM BUT COULD BE TEMPERED A BIT BY THE CLOUDS.
EVEN SO...A SHALLOW MIXING HEIGHT OF ONLY 950MB YIELDS HIGHS OVR
40 DEGREES. LEANED MORE TOWARD PREVIOUS FCST WITH MID 40S ALONG LK
SUPERIOR SHORE NW AND NCNTRL GIVEN SW WIND DIRECTION. IF WE DO SEE
SUNSHINE...HIGHER SUN ANGLE AND DENSELY FORESTED LANDSCAPE/LOWER
ALBEDO WOULD OFFSET RECENT SNOWFALL AND COULD ALLOW FOR ISOLD 50
DEGREE READINGS. SFC DWPNTS INTO THE MID 30S AND MAYBE EVEN HIGHER
FCST TO SURGE INTO UPR LAKES LATER TUESDAY INTO TUESDAY NIGHT. HAVE
ADDED FOG TO FCST MAINLY OVER INLAND AREAS WHERE TEMPS COULD DIP THE
LOWEST. AT THE LEAST...SEEMS LIKE GOOD SETUP FOR PLENTY OF STRATUS.
INCREASING SOUTHERLY WINDS WILL ALSO BE ISSUE FOR LATER TUESDAY INTO
TUESDAY NIGHT. VERY STABLE PROFILE IN LOW-LEVELS BUT EVEN SFC-BLYR
WINDS OFF MODELS POINT TO SOUTH TO SOUTHWEST WINDS NEAR GREAT LAKE
SHORES GUSTING TO 30-35 MPH ON TUESDAY NIGHT INTO WEDNESDAY MORNING.
MODELS CONTINUE TO SHOW COLD FRONT WORKING THROUGH UPR LAKES ON
WEDNESDAY AND NOW IT SEEMS LIKE TREND IS QUICKER IN BRINGING COLDER
AIR INTO WESTERN CWA. GFS SOUNDINGS AT IWD/CMX ARE ESSENTIALLY BLO
0C AS EARLY AS MID MORNING ON WEDNESDAY AND ECMWF LENDS SUPPORT TO
COLDER SCENARIO AS WELL. KEPT MIX OF RAIN/SNOW FOR CNTRL AND EAST...
BUT WENT WITH MAINLY SNOW IN THE WEST. MODEL CONSENSUS WOULD POINT
TO ADVY SNOW ACCUMS IN SOME AREAS OF THE WEST AND CENTRAL...BUT
HIGHER CERTAINTY IN THIS IDEA NOT THERE QUITE YET AS MODELS HAVE
BEEN JUMPING AROUND WITH EXTENT OF UPR WAVE LIFTING ALONG FRONT ON
WEDNESDAY AND HOW FAR WEST TO HAVE THIS WAVE. DO HAVE LIKELY POPS
NOW OVR THE EAST HALF OF THE CWA WHERE WAVE IS MOST LIKELY TO TRACK
AT THIS POINT. GRADUALLY COOLER AIR SETTLES INTO UPR LAKES TO CLOSE
THE WEEK. SOME LK EFFECT COULD OCCUR...THOUGH THERE ARE DIFFERENCES
IN GUIDANCE ON GENERAL WIND DIRECTION. NO NEED TO STRAY FM CONSENSUS
APPROACH FOR NOW...WHICH RESULTS IN SLIGHT CHANCES OF SNOW SHOWERS
THURSDAY AND FRIDAY NEAR LAKE SUPERIOR.
&&
.AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON)
ISSUED AT 1146 AM EST SAT MAR 3 2012
SAW...WITH STRONG NRLY WINDS AND COLDER AND DRIER AIR MOVING IN THIS
AFTERNOON...WINDS WILL SLOWLY DIMINISH...SO CONDITIONS WILL IMPROVE
TO MVFR LATE THIS AFTERNOON FROM IFR. SOME LIGHT LES WILL PERSIST
THROUGH THE REST OF THE PERIOD WITH MVFR CONDITIONS.
CMX/IWD...ALTHOUGH THESE LOCATIONS ARE FARTHER W OF THE DEPARTING
LOW PRESSURE SYSTEM CYCLONIC NNE FLOW WILL SUPPORT SOME -SN AND
IFR/OCNL MVFR CONDITIONS. THE ARRIVAL OF DRIER AIR AND WEAKENING
CYCLONIC FLOW LATE THIS AFTERNOON WILL CAUSE CONDITIONS TO
IMPROVE TO MVFR.
&&
.MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE)
ISSUED AT 533 AM EST SAT MAR 3 2012
NORTH GALES WILL CONTINUE TODAY AS LAKE SUPERIOR IS ON NORTHWEST
FRINGE OF STRONG LOW PRESSURE SYSTEM MOVING INTO QUEBEC. GALES
DIMINISH TONIGHT INTO SUNDAY AS HIGH PRESSURE RIDGE OVER ONTARIO
SLIDES INTO THE REGION. ONCE RIDGE SLIDES OUT TO THE EAST ON MONDAY
A STRONGER LOW PRESSURE IS FCST TO MOVE ACROSS SOUTHERN TIER OF
CANADA. TIGHTER PRESSURE GRADIENT BTWN THE RIDGE AND THE APPROACHING
LOW MAY LEAD TO 30 KT SOUTHERLY WINDS OVR EAST HALF OF LK SUPERIOR
TUESDAY NIGHT INTO WEDNESDAY. STABILITY IS HIGH...BUT IF PRESSURE
FALLS NORTH OF LK SUPERIOR ARE STRONG ENOUGH...COULD SEE GALE GUSTS
OVR EASTERN LK SUPERIOR. COLD FRONT WORKS ACROSS ON WEDNESDAY.
NORTHWEST TO NORTHERLY WINDS IN WAKE OF THE FRONT ARE EXPECTED TO
REMAIN BLO 25 KTS THURSDAY INTO FRIDAY.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
UPPER MICHIGAN...
WINTER STORM WARNING UNTIL 7 PM EST THIS EVENING FOR MIZ013-014.
WINTER STORM WARNING UNTIL 1 AM EST SUNDAY FOR MIZ007.
WINTER STORM WARNING UNTIL 7 AM EST SUNDAY FOR MIZ005-006-085.
LAKE SUPERIOR...
HEAVY FREEZING SPRAY WARNING UNTIL 4 AM EST SUNDAY FOR
LSZ243>245-248>251-263>267.
GALE WARNING UNTIL 7 PM EST THIS EVENING FOR LSZ244-245-248>251-
264>267.
GALE WARNING UNTIL 1 PM EST THIS AFTERNOON FOR LSZ263.
LAKE MICHIGAN...
NONE.
&&
$$
SHORT TERM...JLB
LONG TERM...JLA
AVIATION...07
MARINE...JLA
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
1121 AM CST Sat Mar 3 2012
...UPDATED AVIATION DISCUSSION...
.UPDATE...
/949 AM CST Sat Mar 3 2012/
Water vapor imagery shows a fairly well pronounced PV anomaly moving
south from Northern Plains along the eastern edge of a building ridge
and enhancing the troughing already digging into the central CONUS.
This anomaly will bring cooler air aloft and with surface
temperatures expected to climb into the upper 40s to lower 50s, steep
lapse rates should result. Indeed, modified afternoon soundings yield
a small amount of instability which may be enough get a few showers
going given the enhanced lift with the approaching upper PV anomaly.
However, dry low levels should keep much of the precipitation as
virga so for now have only added a chance for few sprinkles to mainly
just our Kansas zones. The latest NAM, HRRR and 00Z NSSL WRF and
NCEP WRF all develop some showers this afternoon ahead of this
feature from Nebraska into eastern Kansas and have apparently keyed
on the lift and weak instability generated from the approaching upper
wave.
CDB
&&
.DISCUSSION...
The main focus of the forecast will surround a small chance for
precipitation tomorrow and then the upcoming warming trend this week.
Upper level trough responsible for the severe weather outbreak
across the Ohio and Tennessee valleys and into the SE US yesterday
continues to churn across the Great Lakes early this morning. Wrap
around stratus on the back side of the system slowly edging
southward across the bulk of Iowa. Expect some of this cloud cover
to make it into the northern and eastern counties during the day,
which may tend to hold temperatures on the cool side across these
locations. Elsewhere, downslope component to the low level wind
fields combined with deep mixing should allow temperatures to warm
into the mid to upper 40s across the western 2/3rds of the area.
By tomorrow, northwest upper flow pattern will be in place with a
weak embedded wave expected to traverse the upper Midwest. This may
provide a slight chance for some light precipitation across the far
northeast corner of the forecast area. Morning soundings look to
support snow before low level temperatures warm by the afternoon for
more of rain profile. Expect a similar temperature gradient to be in
place again on Sunday with mid to upper 40s by the afternoon hours
across northeast Missouri and readings near the 60 degree mark across
eastern Kansas.
Surface ridge slides east of the area on Monday with southerly low
level flow returning to the region. Wind fields will further
strengthen through the beginning of the work week as pressure falls
take shape across the high plains. This will help transport much
warmer temperatures into the area and therefore continued to push
temperatures above the consensus numbers through Wednesday. Given the
deep southerly low level flow expected to be in place by Tuesday,
still thinking at least lower 70s will be possible across eastern
Kansas/western Missouri by the afternoon hours.
Models continue to advertise the next storm system to move into the
plains on Wednesday with an associated cold front to move into the
forecast area during this time frame. While differences still exists
with the timing and amplitude of this system, guidance has come into
somewhat better agreement. However given continued uncertainty,
maintained pops close to consensus numbers to account.
Deroche
&&
.AVIATION...
For the 18Z TAFS, VFR conditions are expected through the valid
period with scattered clouds developing this afternoon. A few
sprinkles are possible west of the terminals through the afternoon as
well. Winds will become variable overnight, increasing from the west
by late morning and then becoming northwesterly by Sunday afternoon.
CDB
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
WFO EAX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
245 PM CST SAT MAR 3 2012
.SHORT TERM...TONIGHT THROUGH TUESDAY.
LIGHT SPRINKLES OR FLURRIES SHOWING UP ON RADAR AT 20Z WEST OF A
KOLU TO KLNK LINE. RUC FORECAST SOUNDINGS INDICATE SOME MID LEVEL
SATURATION AND INSTABILITY FOR A TIME THIS AFTERNOON BEFORE
DISSIPATING WITH LOSS OF HEATING.
ANOTHER CHANCE OF LIGHT PRECIP COMES INTO THE PICTURE LATE TONIGHT
AS A FAST MOVING CLIPPER SYSTEM DROPS INTO THE NORTHERN PLAINS
THEN CONTINUES INTO THE MID MISSISSIPPI VALLEY ON SUNDAY. NAM AND
GFS SHOW A SIMILAR TRACK IN TAKING THE WAVE ACROSS CENTRAL IOWA
WHILE THE ECMWF IS A BIT FURTHER WEST ALONG THE NEBRASKA IOWA
BORDER. CURRENT FORECAST WILL FOLLOW THE MORE EASTERLY TRACK AND
BRING SOME SMALL POPS INTO NORTHEAST NEBRASKA LATE TONIGHT WITH
LIGHT SNOW OR FLURRIES JUST EAST OF THE AREA SUNDAY MORNING.
NORTHWEST WINDS WILL ALSO PICK UP ON THE BACKSIDE OF THIS SYSTEM
SUNDAY WITH ADVISORY LEVEL WINDS INDICATED FOR SUNDAY AFTERNOON
ACROSS ALL BUT THE FAR SOUTHERN PART OF THE CWA. WILL NOT ISSUE
ANY HEADLINES AT THIS TIME AND LET LATER SHIFT REEVALUATE TRACK OF
THE SYSTEM IN NEXT MODEL RUN.
WARMER AIR RETURNS MONDAY INTO TUESDAY AS RIDGE MOVES OVER THE
REGION AND FLATTENS AHEAD OF THE NEXT UPPER WAVE DROPPING INTO THE
WESTERN CONUS. MUCH ABOVE NORMAL TEMPERATURES EXPECTED ON TUESDAY
WITH HIGHS APPROACHING 70 IF MODELS MAINTAIN TIMING OF COLD FRONT
COMING INTO THE AREA LATE ON TUESDAY IN FUTURE RUNS.
.LONG TERM...TUESDAY NIGHT THROUGH SATURDAY.
THE MAIN CONCERN IN THIS PERIOD IS THE CHANCE OF PRECIPITATION FROM
TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. LATEST MODELS WERE IN GOOD
AGREEMENT WITH THE LARGE SCALE PATTERN AT THE BEGINNING OF THIS
PERIOD...SHOWING A 500 MB TROUGH OVER THE ROCKIES. ENERGY WITH THIS
TROUGH SPLITS INTO TWO PIECES. ONE SHOULD AFFECT THE NORTHERN PLAINS
AND THE OTHER BRIEFLY BECOMES A CLOSED LOW OVER THE FOUR CORNERS
REGION. SOME LIGHT PRECIPITATION IS POSSIBLE ALONG AND BEHIND A COLD
FRONT THAT WILL PUSH SOUTHEAST THROUGH THE REGION TUESDAY NIGHT.
GFS SEEMS TO HAVE TRENDED TOWARD YESTERDAYS ECMWF SOLUTION...AND THE
12Z GFS SHOWED 850 MB DEWPOINTS 0 TO 6 DEGREES C AHEAD OF THE FRONT.
LAPSE RATES ARE DECENT...AND 850 MB LIFTED INDICES DROP TO NEAR ZERO
TUESDAY NIGHT...SO SOME THUNDER APPEARS POSSIBLEIN SOUTHEAST
NEBRASKA. CHANCES INCREASE FOR WEDNESDAY AND POTENTIAL RAINFALL
AMOUNTS ARE HIGHER...MAINLY ACROSS SOUTHEAST NEBRASKA AND SOUTHWEST
IOWA.
EXPECT DRY CONDITIONS THURSDAY THROUGH SATURDAY...WITH HIGHS MOSTLY
IN THE 40S TO LOWER 50S.
&&
.AVIATION...
18Z TAFS FOR KOMA...KLNK AND KOFK.
MVFR CIGS CONTINUE TO MOVE OVER SERN SD AND TOWARD NERN NEB. WL
CONTINUE TO MONITOR BUT DID THROW IN A TEMPO MVFR CIG IN KOFK THIS
AFTERNOON. MID CLOUDS ARE EXPECTED THROUGH THE OVERNIGHT HOURS AS
A SFC TROF MOVES TOWARD THE AREA. THIS WILL BRING A BRIEF SHIFT TO
SOUTHWEST WINDS AND A SMALL CHANCE FOR PCPN IN NORTHEAST NEBRASKA.
DID NOT INCLUDE ANY PCPN MENTION IN KOFK TAF BUT MAY BE NEEDED IN
LATER ISSUANCES. ANY PCPN THAT DOES FALL LOOKS TO REMAIN LIGHT.
SFC WINDS WL TURN TO THE NORTHWEST BY MID TO LATE MORNING AND
BECOME QUITE GUSTY INTO THE END OF THE TAF PD.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
FOBERT/MILLER/KERN
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1245 PM CST SAT MAR 3 2012
.UPDATE...MORNING UPPER AIR ANALYSIS REVEALS LONG WAVE
TROUGHING OVER THE CENTRAL CONUS...WITH NORTHWESTERLY UPPER LEVEL
FLOW OVER THE WESTERN CONUS AND SOUTHWESTERLY UPPER LEVEL FLOW
ACROSS THE EAST. MID AND UPPER LEVEL JET ENERGY REMAINS RELEGATED TO
THE WEST...SOUTH AND EAST OF THE CENTRAL PLAINS...BUT THERE IS AN
850MB-700MB JET STREAK ON THE ORDER OF 35-50KTS OVER OUR AREA. WATER
VAPOR IMAGERY INDICATES MID LEVEL MOISTURE IS PRETTY MEAGER OVER THE
CENTRAL PLAINS...ALTHOUGH THERE IS INCREASING MID LEVEL MOISTURE
ADVANCING INTO PORTIONS OF THE NORTHWESTERN AND CENTRAL CONUS.
VISIBLE SATELLITE IMAGERY SHOWS A DEVELOPING CU FIELD OVER MUCH OF
NEBRASKA AS OF MIDDAY...WITH THESE CLOUDS BEGINNING TO OVERTAKE
OUR CWA. AT THE SURFACE A RIDGE OF HIGH PRESSURE CONTINUES TO
DOMINATE OUR AREA...WITH LOW LEVEL FLOW REMAINING FROM THE
WEST/NORTHWEST AS A RESULT.
VERY STEEP LOW AND MID LEVEL LAPSE RATES ARE HELPING PROMOTE EXPANSIVE
BUT SHALLOW CU DEVELOPMENT ACROSS MUCH OF THE CWA NOW...WITH KUEX
SHOWING SOME RETURNS OVER NORTHERN PORTIONS OF OUR AREA AS OF
1830Z. FORECAST SOUNDINGS FROM LAPS AND RUC ANALYSIS HOWEVER
INDICATE THE LOWER TROPOSPHERE REMAINS VERY DRY ACROSS OUR ENTIRE
CWA...THUS PREVENTING MUCH OF THIS PRECIPITATION FROM REACHING THE
SURFACE. WENT AHEAD AND INTRODUCED ISOLATED SPRINKLES TO THE AREA JUST
IN CASE A FEW DROPS OF RAIN CAN MAKE IT TO THE GROUND...BUT CERTAINLY
VIRGA AND OTHERWISE DRY WEATHER ARE ANTICIPATED THROUGH THE
REMAINDER OF THE AFTERNOON.
FORECAST PROXIMITY SOUNDINGS FROM THE NAM...OPERATIONAL GFS AND
RUC ALL SUGGEST THE AFTERNOON BOUNDARY LAYER WILL BE VERY DEEP
AGAIN THIS AFTERNOON...WITH MIXING RISING TO NEAR 700MB. BIGGEST
DIFFERENCE BETWEEN YESTERDAY AND TODAY IS THE SUBTLE INCREASE IN
MID LEVEL MOISTURE...WHICH IS RESULTING IN LITTLE TO NO DROP-OFF
IN AFTERNOON DEW POINTS AS FULL BOUNDARY LAYER MIXING COMMENCES.
WILL GO AHEAD AND FORECAST DEW POINTS TO HOLD NEAR STEADY ACROSS
THE CWA THROUGH THE REMAINDER OF THE AFTERNOON. HIGH TEMPERATURES
ARE STILL FORECAST TO RISE INTO THE 40S TO LOW 50S...BUT THESE
TEMPERATURES WOULD BE EVEN WARMER IF NOT FOR THE EXPANSIVE CU
DEVELOPMENT CURRENTLY OVERTAKING THE AREA. ASSUMING THE CLOUD
COVER CAN INDEED KEEP TEMPERATURES DOWN TO WHERE THEY ARE CURRENTLY
FORECAST...THEN RESULTANT SURFACE RH VALUES SHOULD NOT DROP BELOW
21% OR 22% ACROSS OUR SOUTHWEST...AND REMAIN EVEN HIGHER FARTHER
NORTHEAST. GIVEN ALL THIS...RFW ISSUANCE IS NOT PLANNED FOR
TODAY...BUT WILL CONTINUE TO MONITOR CLOSELY THROUGH THE REMAINDER
OF THE AFTERNOON.
DEEP BOUNDARY LAYER MIXING AND STRONG WINDS BETWEEN 850MB AND 700
MB WILL PROMOTE ANOTHER BREEZY DAY ACROSS THE AREA...ESPECIALLY
ACROSS OUR WEST. THAT BEING SAID...GUIDANCE KEEPS ALL LOCATIONS ACROSS
OUR CWA UNDER WIND ADVISORY CRITERIA...THUS NO WIND HEADLINES ARE
ANTICIPATED TODAY.
&&
.PREV DISCUSSION... /ISSUED 1118 AM CST SAT MAR 3 2012/
AVIATION...18Z KGRI TAF. VFR CONDITIONS TO CONTINUE THROUGH THE
NEXT 24 HOURS. AFTERNOON CU NEAR 4000FT AGL WILL LIKELY BE
OBSERVED...WITH PERHAPS SOME VERY LIGHT PRECIPITATION POSSIBLE AT
THE TERMINAL. WITH LOWER TROPOSPHERIC MOISTURE SO LIMITED
HOWEVER...VIRGA IS MUCH MORE LIKELY THROUGH THE AFTERNOON AND
EARLY EVENING HOURS. CU FIELD WILL DIMINISH TOWARDS SUNSET AS
DIABATIC HEATING IS LOST...BUT DEVELOPING CLOUDS NEAR 8000FT AGL
ARE THEN FORECAST BY 01Z...WITH CLOUDS THEN EXPECTED TO DISSIPATE
12Z ONWARD. SURFACE WINDS WILL REMAIN FROM THE WEST/NORTHWEST THIS
AFTERNOON AT 20KTS...GUSTING TO AROUND 28KTS. SURFACE WINDS WILL
DIMINISH AROUND SUNSET AND THEN INCREASE ONCE AGAIN DURING THE DAY
SUNDAY. VISIBILITY RESTRICTIONS ARE NOT ANTICIPATED THROUGH THE
NEXT 24 HOURS.
PREV DISCUSSION... /ISSUED 522 AM CST SAT MAR 3 2012/
SHORT TERM...SATURDAY THROUGH MONDAY.
LARGE SCALE PATTERN PUTS US GENERALLY WITHIN NORTHWEST FLOW WITH
SMALL PERTURBATIONS SWIFTLY PASSING BY FOR THE NEXT COUPLE OF DAYS
AS WE LIE BETWEEN RIDGING IN THE WEST AND TROUGH IN THE EAST. EACH
DAY SHOULD BE RATHER BREEZY WITH CONSIDERABLE MIXING ANTICIPATED.
FOR TODAY...MODELS/WATER VAPOR ARE STILL POINTING TOWARD A SMALL
SCALE PERTURBATION KICKING UP CONSIDERABLE CLOUDINESS ESPECIALLY
NORTHEAST...BUT SOUNDING ARE SO DRY AT LOWER LEVELS THAT I AM STILL
NOT PUTTING IN ANY PRECIPITATION AT THIS TIME. WITH THE ADDITIONAL
ANTICIPATED SKY COVER...I EXPECT THAT THIS WILL AFFECT HIGH
TEMPERATURES EXCEPT IN THE SOUTH WHERE WARMER AND DRIER CONDITIONS
WILL PUT US SOMEWHAT CLOSE AGAIN TO FIRE WEATHER ISSUES...ALTHOUGH
NOT ENOUGH OF A SLAM DUNK TO ISSUE AN RFW.
SUNDAY LOOKS EVEN WINDIER AND COULD BE A WIND ADVISORY
DAY...ESPECIALLY NORTH. RIDGE IN THE WEST FLATTENS AND MOVES INTO
THE PLAINS FOR MONDAY...CAUSING TEMPERATURES TO SOAR WELL ABOVE
NORMAL. KEEPING A DRY FORECAST AND RELATIVE HUMIDITY LEVELS COULD
APPROACH 20 PERCENT IN THE WEST AND SOUTH FOR EACH OF THE THREE DAYS
OF THIS FORECAST.
LONG TERM...12Z TUESDAY THROUGH 0Z SATURDAY.
BOTH THE GFS AND THE ECMWF ARE IN GOOD AGREEMENT 12Z TUESDAY THROUGH
0Z THURSDAY. BEGINNING 12Z TUESDAY. AT THE UPPER LEVELS...A TROUGH
AXIS BEGINS TO SHIFT OFF THE EAST COAST WHILE THE MAJORITY OF THE
CENTRAL UNITED STATES REMAINS UNDER THE INFLUENCE OF A LARGE RIDGE.
ANOTHER TROUGH AXIS BEGINS TO DEEPEN ALONG THE WEST COAST. AT
H850...TEMPS NEAR 13 DEGREES CELSIUS SURGE ALONG THE RIDGE AXIS INTO
THE CENTRAL PLAINS ALLOWING MUCH OF THE REGION TO CLIMB INTO THE
UPPER 60S TO NEAR 70S FOR HIGHS ON TUESDAY.
THESE WARMER TEMPERATURES ARE SHORT LIVED HOWEVER...AS THE UPPER
LEVEL TROUGH AXIS ACROSS THE WEST COAST BEGINS TO PUSH EASTWARD BY
WEDNESDAY MORNING. BOTH THE GFS AND THE ECMWF SUGGEST A STRONG COLD
FRONTAL BOUNDARY WILL PUSH THROUGH THE PLAINS BY WEDNESDAY MORNING
CLEARING MUCH OF THE CWA BY 12Z. ALONG THE FRONT...SLIGHT CHANCES
FOR A RAIN SNOW MIX IS POSSIBLE ACROSS THE EASTERN PORTION OF THE
CWA. BEHIND THE FRONT...COOLER 850 TEMPS RANGING FROM -4 TO -6
DEGREES CELSIUS WILL KEEP HIGH TEMPERATURES MUCH COOLER ON TUESDAY.
DECIDED TO LOWER TEMPERATURES ON WEDNESDAY NEAR MOS GUIDANCE WHICH
IS 20 TO 25 DEGREES COOLER THAN TUESDAY.
THE ECMWF AND THE GFS BEGIN TO DIFFER QUITE A BIT BEGINNING ON
THURSDAY. AS THE UPPER LEVEL TROUGH AXIS PUSHES ACROSS THE
CONUS...THE EC CLOSES A CUTOFF LOW ACROSS THE SOUTHWEST US WHILE THE
MAIN TROUGH AXIS ACROSS THE NORTH CENTRAL UNITED STATES BEGINS TO
DEEPEN. AS A RESULT...SURFACE HIGH PRESSURE SETTLES ACROSS THE
CENTRAL PLAINS BY THURSDAY. COLDER 850S TEMPS NEAR -13 DEGREES CELSIUS
SURGE SOUTH ACROSS THE DAKOTAS INTO THE EASTERN CENTRAL PLAINS BY
THURSDAY NIGHT. WITH THIS SOLUTION...TEMPERATURES BOTH THURSDAY
NIGHT AND FRIDAY WILL BE CONSIDERABLY COOLER...WITH FRIDAYS HIGH
TEMPERATURES RIGHT AROUND FREEZING. WIND SPEEDS AT 850 ARE ALSO NEAR
25 AND 30 KNOTS INDICATING A WINDY DAY ACROSS THE PLAINS.
WITH THE GFS SOLUTION...THE UPPER LEVEL LOW ALSO DEVELOPS A CUTOFF
LOW ACROSS THE SOUTHWEST UNITED STATES...HOWEVER...THE MAIN TROUGH
AXIS DOES NOT DEEPEN QUITE AS MUCH. THE SURFACE HIGH PRESSURE
SYSTEM REMAINS WEAKER AND FARTHER NORTH THAN THE EC SOLUTION. BY
THURSDAY NIGHT...850 TEMPERATURES REMAIN NEAR 3 TO 5 DEGREES CELSIUS
CLIMBING TO NEAR 7 DEGREES CELSIUS ON FRIDAY. THE GFS SOLUTION
SUGGESTS HIGH TEMPERATURES ON FRIDAY COULD BE NEAR 50 DEGREES AND
WIND SPEEDS COULD REMAIN UNDER 10 KTS.
&&
.GID WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
KS...NONE.
&&
$$
UPDATE/AVIATION...BRYANT
SHORT TERM...HEINLEIN
LONG TERM...SALTZMAN
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
327 PM EST SAT MAR 3 2012
.SYNOPSIS...
COLD FRONT WILL MOVE OFFSHORE BY LATER TODAY...BUT CHILLY RAIN
WILL LINGER OVER THE EASTERN CAROLINAS INTO SUNDAY MORNING AS A
WAVE OF LOW PRESSURE DEVELOPS ALONG THE COLD FRONT. MUCH COOLER
AND DRIER HIGH PRESSURE WILL BUILD INTO THE AREA SUNDAY AFTERNOON
THROUGH TUESDAY. A WARMING TREND WILL BEGIN MID WEEK AS THE HIGH
PRESSURE SHIFTS OFFSHORE.
&&
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM SATURDAY...FOR THE LATEST SFC ANALYSIS INCLUDING USAGE
OF VARIOUS SAT IMAGERY CHANNELS...ISOPLETHING VARIOUS SFC PARAMETERS
OBTAINED FROM METAR OBSERVATIONS...AND THE ACTUAL AND HOURLY PROGGED
SFC WIND FIELD FROM THE HRRR MODEL. ALL OF THIS INDICATES THE COLD
FRONT HAS PUSHED TO THE DOORSTEPS OF THE ILM CWA. THE COLD FRONT
WILL STAGGER TO AND JUST OFF THE CAROLINA COASTS EARLY THIS EVENING.
MODELS INDICATE A BRIEF STATIONARY PHASE ALLOWING WEAK SFC LOWS
TO DEVELOP ALONG IT. THE LOWS WILL CONSOLIDATE INTO 1 AND BEGIN TO
ACCELERATE NE AWAY FROM THE U.S. MAINLAND BY EARLY SUNDAY MORNING.
THIS ACCELERATION IS DUE TO A KIC-START OR PUSH FROM A RATHER POTENT
SOUTHERN STREAM S/W TROF THAT TRACKS FROM TX TO THE FLORIDA PAN
HANDLE BY SUNDAY DAYBREAK. WILL BE LOOKING AT STRATIFORM LIGHT TO
MODERATE RAINS THROUGHOUT THE NEAR TERM. HPC 24 HR RAINFALL
ESTIMATES THRU DAYBREAK SUN GIVES THE ILM CWA A RANGE OF
AMOUNTS...WITH 1 INCH WEST OF I-95...AND POSSIBLY UP TO 3 INCHES
ALONG THE IMMEDIATE COAST. CAA SURGE WILL BEGIN AFTER DAYBREAK
SUNDAY AS SEEN BY THE TIGHT GRADIENT OF 8H TEMPS AND THE 1K-8H
PARTIAL THICKNESSES. VARIOUS MODEL GUIDANCE COMPROMISED.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 3 PM SATURDAY...MID TO UPPER TROUGH WILL FINALLY LIFT OFF
TO THE NORTHEAST PULLING ANY LINGERING PCP ALONG WITH IT BY SUN
AFTN. PCP WATER VALUES DROP OUT FROM OVER AN INCH SUN MORNING TO
AROUND A QUARTER OF AN INCH BY DAYS END. OVERALL EXPECT A CLEARING
TREND THROUGH SUNDAY AFTERNOON.
A DEEP W-NW FLOW SUN AFTN WILL BACK TO THE W-SW LATE SUN INTO
MONDAY AS ANOTHER SHORTWAVE MOVES DOWN AROUND THE LONGER WAVE MID
TO UPPER TROUGH. THIS CLIPPER WILL PRODUCE A LOW LEVEL REFLECTION
WHICH MODELS NOW SHOW AS LOW PRESSURE MOVING EAST ALONG THE NC/VA
BORDER THROUGH MON AFTN BEFORE SHIFTING OFF SHORE BY MON EVENING.
LOOKS LIKE BEST SHORTWAVE ENERGY WITH THIS SYSTEM WILL SKIM BY
JUST TO THE NORTH OF OUR CWA. PCP WATER VALUES INCREASE UP NEAR A
HALF INCH WHICH BELIEVE WILL TRANSLATE INTO MORE IN THE WAY OF
CLOUDS THAN ANY PCP. WILL KEEP PCP NORTH CLOSER TO LOW AND WILL
LEAVE OUR DRY ON MONDAY AFTN. ONCE THE H5 TROUGH FINALLY CLEARS
THE COAST BY MON NIGHT A DEEP N-NW FLOW WILL SET UP. EXPECT A
REINFORCING SHOT OF DRY AND COOL AIR ON FRONT END OF HIGH PRESSURE
SYSTEM BUILDING EAST. STRONG HIGH PRESSURE WILL BE ALMOST OVERHEAD
BY END OF SHORT TERM PERIOD. OVERALL THE SHORT TERM PERIOD WILL
EXPERIENCE DRIER AND COOL WEATHER
AS FOR TEMPS...MAX CAA WILL CONTINUE THROUGH SUNDAY WITH 850 TEMPS
DROPPING DOWN NEAR -4C BY LATE SUN AFTN. THERE WILL BE A SLIGHT
REBOUND ON MONDAY AS WINDS BACK TO THE W-SW AS LOW SKIRTS BY TO
THE NORTH HELPING TO BOOST MAX TEMPS ON MON...BUT ANOTHER SURGE WILL
OCCUR MON NIGHT WITH 850 TEMPS DROPPING AS LOW AS -6 BY MIDNIGHT.
COOLEST TEMPS WILL COME ON SUNDAY AS CLOUDS AND RAIN IN THE
MORNING WILL KEEP TEMPS IN THE 40S. BY SUN AFTN TEMPS SHOULD GET A
CHANCE TO RISE TO AROUND 50. ENOUGH RADIATIONAL COOLING THROUGH
SUN EVENING WILL ALLOW TEMPS TO DROP AND ALTHOUGH THERE WILL BE
SLIGHT WAA AFTER MIDNIGHT THE ATMOSPHERE SHOULD NOT MIX MUCH OF
THIS DOWN AND SHOULD END UP WITH TEMPS IN THE MID 30S FOR LOWS.
WITH SLIGHT WAA AND PLENTY OF SUNSHINE ON MONDAY...TEMPS WILL WARM
TO AROUND 60. MAY REMAIN SLIGHTLY COOLER NORTHERN TIER COUNTIES AS
CLOUDS MAY MOVE ACROSS IN THE AFTN ASSOCIATED WITH LOW TO THE
NORTH. TEMPS MON NIGHT WILL BE THE COOLEST AS ANOTHER SURGE OF
COLD AND DRY AIR WILL BE FOLLOWED BY DECENT RADIATIONAL COOLING
FOR A FEW HOURS BEFORE DAYBREAK...ALLOWING READINGS TO DROP CLOSE
TO FREEZING MOST PLACES.
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
AS OF 300 PM SATURDAY...DRY WITH A WARMING TREND EXPECTED THROUGH
LATE WEEK AS 500MB RIDGING DEVELOPS ACROSS THE EAST COAST. MODEL
GUIDANCE SHOWS NO AGREEMENT FOR THE END OF THE WEEK...BUT THE NEXT
CHANCE OF RAIN WILL LIKELY OCCUR LATE FRIDAY/SATURDAY.
TUESDAY WILL FEATURE THE ONLY BELOW CLIMO DAY OF THE PERIOD DUE TO
COOL HIGH PRESSURE RIDGING DOWN THE COAST CONTINUING WEAK CAA AND
LIGHT N/NE WINDS...AND TUE NIGHT WILL DROP INTO THE MID 30S. HIGH
DRIFTS OFFSHORE BEGINNING WEDNESDAY BUT ELONGATES BACK TOWARDS THE
CAROLINAS THROUGH FRIDAY. AT THE SAME TIME...INVERTED TROUGH
DEVELOPS JUST OFFSHORE WEDNESDAY BEFORE PUSHING INLAND ON SYNOPTIC
EASTERLY FLOW THURSDAY. FORECAST SOUNDINGS SUGGEST AN INCREASE IN
LOW LEVEL CLOUD COVER...WHILE MID LEVELS REMAIN EXTREMELY DRY AND
PWATS RISE TO ONLY AROUND ONE-HALF INCH...SO BELIEVE INHERITED DRY
FORECAST IS VALID. OTHER THAN ENHANCED CLOUD COVER...E/NE WINDS ON
LEE SIDE OF THIS TROUGH WILL ACT TO KEEP TEMPS A LITTLE BELOW
GUIDANCE...LOW/MID 60S WED AND NEAR 70 THU.
CONFIDENCE REMAINS LOW FOR THE END OF THE WEEK DUE TO LACK OF MODEL
AGREEMENT. GFS CONTINUES ITS RUN-TO-RUN INCONSISTENCY SO WILL
PERSIST THE HPC/ECMWF BLEND WHICH SLOWLY RAMPS POP FRI NIGHT AND
SATURDAY WITH THE APPROACH OF A COLD FRONT. MOISTURE RETURN LOOKS
RATHER LIMITED AHEAD OF THIS BOUNDARY...WHICH WHEN COMBINED WITH THE
LACK OF CONFIDENCE PROMPTS ONLY SCHC THIS FAR OUT. TEMPS FRI REMAIN
WELL ABOVE CLIMO...POTENTIALLY FALLING MUCH COOLER SATURDAY BEHIND
THE FRONT.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
AS OF 18Z...WIDESPREAD RAIN IS OCCURRING EARLY THIS AFTERNOON AHEAD
OF AN APPROACHING COLD FRONT LOCATED AT 15Z NORTHWEST OF KLBT. THE
FRONT WILL MOVE THROUGH THE FLO/LBT TERMINALS THIS AFTERNOON AND THE
COASTAL TERMINALS THIS EVENING WITH WINDS SHIFTING TO THE NORTH.
THROUGH THE AFTERNOON EXPECT LIGHT RAIN AND VFR CONDITIONS WITH
TEMPO MVFR IN THE AREAS OF HEAVIER RAIN. REDUCED FLIGHT CONDITIONS
WILL BE MAINLY DUE TO REDUCED VISIBILITIES. THERE IS A CHANCE OF
IFR VISIBILITIES IN RAIN AT CRE/MYR EARLY THIS AFTERNOON BUT SINCE
RADAR TRENDS INDICATE RAIN BECOMING LIGHTER DO NOT THINK THIS WILL
PERSIST.
LATE THIS EVENING AND OVERNIGHT A SURFACE WAVE WILL MOVE UP THE
FRONT LOCATED JUST OFFSHORE SPREADING MODERATE TO HEAVY RAIN ACROSS
THE TERMINALS. AHEAD OF THE SURFACE WAVE THERE WILL BE A GOOD CHANCE
OF THUNDERSTORMS AND HEAVY RAIN AT THE COASTAL TERMINALS DEVELOPING
BY LATE AFTERNOON AND EARLY EVENING. THERE SHOULD BE A LESS CHANCE
OF THUNDERSTORMS AT FLO/LBT. ALTHOUGH IFR VISIBILITIES ARE LIKELY
LATE THIS AFTERNOON AND EVENING WITH THE HEAVY RAIN...AS THE RAIN
SATURATES THE COOLER AIRMASS THE PROBABILITIES OF IFR CEILING
DEVELOPMENT WILL INCREASE WITH ALL TERMINALS IFR/LIFR BY
MIDNIGHT/EARLY MORNINGS. RAIN TAPERS OFF SUNDAY MORNING BUT WILL
ONLY INDICATE A SLIGHT IMPROVEMENT OF FLIGHT CONDITIONS. FLIGHT
CONDITIONS COULD IMPROVE FASTER THAN ANTICIPATED IF THE SURFACE
WAVES MOVES FASTER UP THE COAST THAN EXPECTED.
EXTENDED OUTLOOK...VFR DEVELOPING SUNDAY AFTERNOON...CONTINUING
THROUGH THURSDAY.
&&
.MARINE...
.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 PM SATURDAY...SMALL CRAFT ADVISORY WILL BE STRONGLY WORDED
LATER TONIGHT AS CAA BEGINS TO FILTRATE INTO THE ILM COASTAL WATERS.
WILL BE LOOKING AT WINDS VEERING FROM SW 15 TO 25 KT TO THE NW AND N
AT 25 TO 30 KT WITH A FEW GUSTS TO 35 KT TOWARD DAYBREAK SUN.
LOOKING AT PROGGED 925MB WINDS...THE SLIGHTLY HIGHER WINDS STAY
MAINLY SOUTH OF THE ILM CWA. SEAS WILL RAMP UP TO 4 TO 7 FT...WITH 8
FOOTERS OVER THE OUTER WATERS OFF CAPE FEAR. AREAS TO WIDESPREAD
LIGHT TO MODERATE RAIN WILL PREVAIL ACROSS THE WATERS...LOWERING
VSBY TO 1 TO 3 NM AT TIMES.
SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
AS OF 3 PM SATURDAY...LOW PRESSURE WILL LIFT OFF TO THE NORTHEAST
ON SUNDAY WITH STRONG NW WINDS BEHIND IT. ANY LINGERING PCP WILL
TAPER OFF THROUGH THE AFTERNOON AS WINDS BEGIN TO BACK TO THE W-NW
AS FIRST SHORTWAVE MOVES EAST AND ANOTHER SHORTWAVE RIDES DOWN
THROUGH MAIN H5 TROUGH. WINDS MAY WEAKEN SLIGHTLY BY SUN AFTN TO
NEAR 20 KTS BUT MAY SEE ANOTHER SURGE IN WINDS UP NEAR 25 KTS BY LATE
SUNDAY. AS SECOND CLIPPER SYSTEM TRACKS EAST THROUGH MONDAY...THE
ASSOCIATED SFC LOW WILL TRACK EAST ACROSS THE NC/VA BORDER. THIS
WILL ALLOW WINDS TO BACK EVEN FURTHER TO THE W-SW WHILE GRADIENT
INCREASES AGAIN. OVERALL EXPECT AN OFF SHORE NW FLOW SUN MORNING
UP AROUND 25 KTS AND THEN DECREASING SLIGHTLY BEFORE INCREASING
ONCE AGAIN AS WINDS BACK TO THE W-SW. WINDS AND SEAS IN THE OUTER
WATERS WILL REMAIN CLOSE TO SMALL CRAFT ADVISORY CONDITIONS
THROUGH MUCH OF THE SHORT TERM PERIOD. SEAS WILL BE 5 TO 7 FT IN
OUTER WATERS TO START ON SUNDAY AND MAY DECREASE TO 4 TO 6 FT BUT
WILL INCREASE AGAIN THROUGH MONDAY AS GRADIENT TIGHTENS AS LOW
TRACKS BY TO THE NORTH. SHOULD SEE ANOTHER COLD SURGE BEHIND THIS
SYSTEM MON EVENING BUT OFFSHORE FLOW WILL ALLOW SEAS TO DROP BELOW SCA
THRESHOLDS BY MON NIGHT.
LONG TERM /TUESDAY THROUGH THURSDAY/...
AS OF 300 PM SATURDAY...HIGH PRESSURE DRIFTING OFFSHORE THE MID
ATLANTIC CREATES NE WINDS OF 10-15 KTS THROUGH TUESDAY. THIS BUILDS
2-4 FT NE WIND WAVES...WITH THE EXCEPTION BEING THE SHADOWED REGION
SW OF FRYING PAN SHOALS...WHERE ONLY 1-2 FT SEAS WILL DEVELOP. HIGH
PRESSURE DRIFTS FURTHER OFFSHORE WED/THURS...BUT CONTINUES TO RIDGE
BACK INTO THE CAROLINAS. THIS PRODUCES FAIRLY UNIFORM E/SE WINDS
AROUND 10 KTS...AND SEAS SLOWLY BUILDING TO 3-4 FT. INITIALLY THE
WAVE SPECTRUM WILL BE DOMINATED BY AN E/SE WIND CHOP...BUT GRADUALLY
AN AMPLIFYING SE SWELL WILL BUILD DUE TO INCREASINGLY LONG SE FETCH
AROUND HIGH PRESSURE.
&&
.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL NOON EST SUNDAY FOR AMZ250-252-254-
256.
&&
$$
NEAR TERM...DCH
SHORT TERM...RGZ
LONG TERM...JDW
AVIATION...MRR