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175
FXUS61 KLWX 311534
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1134 AM EDT FRI OCT 31 2014

.SYNOPSIS...

LOW PRESSURE IS DESCENDING FROM THE GREAT LAKES...AND WILL CROSS THE
CAROLINAS SATURDAY BEFORE STRENGTHENING OFFSHORE WHILE HEADING
TOWARDS CAPE COD SUNDAY. HIGH PRESSURE WILL RETURN TO THE AREA MONDAY
AND TUESDAY FOLLOWED BY ANOTHER COLD FRONT DURING MIDWEEK.

&&

.NEAR TERM /THROUGH SATURDAY/...

W.V. STLT IMGRY SHOWS SHORT WV HAS PUSHED INTO WI. THIS WILL DIVE
INTO SC SAT AS UPPER LEVEL PATTERN UNDERGOES SUBSTANTIAL
AMPLIFICATION W/ A RDG OVR THE CENTRAL PART OF THE COUNTRY AND A
LARGE TROF DVLPG OFFSHORE AS THE NORTHERN AND SOUTHERN STREAMS
PHASE.

WITH THIS SOUTHWARD TRAJECTORY...FORCING WILL BE FOCUSED OVER THE
MOUNTAINS FOR THE FIRST STAGE OF THIS SYSTEM. SOME RAIN SHOWERS
ARE POSSIBLE THIS AFTERNOON THERE BUT MUCH OF CENTRAL MD AND VA
WILL BE IN A SQUEEZE PLAY UNTIL TONIGHT OR SATURDAY WHEN THE
SYSTEM WINDS UP AND BROAD SCALE LIFT WILL PRODUCE SHOWERS AREA-
WIDE. HOWEVER...ANY HEAVIER PRECIPITATION FROM THE COASTAL LOW
WILL LIKELY REMAIN TO THE EAST OF THE AREA.

IN TERMS OF ANY SNOWFALL...AT LEAST THROUGH SATURDAY COLD ADVECTION
WILL BE VERY MINIMAL WITH THIS OCCLUDED SYSTEM. THE 850-1000 TCKNS
DOES NOT GO SUB 1300M UNTIL THE LOW HAS DVLPD OFFSHORE. SNOW
IS XPCTD TO BE  LIMITED TO THE VERY HIGHEST ELEVATIONS OF WV...AND
MOSTLY AS A RAIN/SNOW MIX AT THAT. THE SNOW WILL BE FAVORED DURING
DIURNAL MINIMUMS IN TEMPERATURE AND ANY SLUSHY ACCUMULATIONS WILL
BE MINOR.

HIGH TEMPERATURES TODAY WILL RANGE FROM THE UPPER 40S AT HIGHER
ELEVATIONS TO NEAR 60 IN THE LOWLANDS. LOWS TONIGHT TEMPERED BY
CLOUD COVER IN RANGING FROM THE MID 30S HIGHLANDS TO MID 40S EAST.
PRECIPITATION SATURDAY WILL BE MOST WIDESPREAD WEST OF THE BLUE
RIDGE ON SATURDAY AND WILL LIMIT HIGHS A BIT MORE THERE...WELL INTO
THE 40S. NEAR 50 TO THE EAST. NORTHERLY WINDS WILL ALSO INCREASE
ON SATURDAY AS THE LOW STRENGTHENS OFF THE COAST.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...

BLV WINDS MAY END UP BEING THE BIGGEST STORY FM THE UPCOMING SYSTEM.

BY SAT NGT...S/WV ENERGY WUD HV SHIFTED OFF THE ATLC CST...INDUCING
CYCLOGENESIS NE OF CAPE HATTERAS. IN TERMS OF PCPN E OF THE
APLCHNS...THAT PRETTY MUCH WL MARK THE END...AS DRIER AIR WL WORK
IN ON THE NW SIDE OF THE CYCLONE. HV OPTED TO HOLD ONTO MORE CLDS
THAN GFS INDICATING...PARTLY DUE TO TIMING/UNCERTAINTY DIFFS AND
THE OTHER PART DUE TO LOW H5 HGTS/PVA STILL PIVOTING ACRS CWFA.
WINDS MAY BE THE BIGGEST IMPACT...BUT THE NOCTURNAL TIMING MAY
PREVENT THE FULL 30-40 KT AVBL H9-8 FM MIXING DOWN. WL BE KEEPING
GUSTS 25-30 MPH.

ACRS THE MTNS...THE AMS WL BE COOLING SUFFICIENTLY FOR SOME SNOW.
HWVR...THE BEST DYNAMIC COOLING WL PASS S OF AREA. THIS LEAVES ONLY
A MARGINALLY FVRBL AMS W/ WARM GRND. SNOW TOTALS 1-2" IN THE HIGHER
ELEVS. IT IS NOT OUT OF THE QSTN THAT ACCUMS COULD BE ENUF TO
REACH ADVSRY LVL...BUT THIS IS NOT A SLAM DUNK AND WL LV THIS TO
BE DECIDED LATER..

SUNDAY LOOKS LK A WINDY DAY. H8-5 RDGG BLDS QUITE QUICKLY
SUNDAY...SHUTTING OFF UPSLP SHSN. A TIGHT PRES GRAD OVER AREA FOR
MUCH OF THE DAY...AND BETTER MIXING. HV 30-35 MPH GUSTS IN GRIDS.

MIN-T IN THE 30S AREAWIDE SAT NGT/SUN MRNG...AND TEMPS STRUGGLING
TO REACH 50F SUN AFTN.

SUN NGT LOOKS QUITE CHILLY AS RDG BLDS OVER AREA. CLR SKIES/DECOUPLING
WNDS/DEWPTS IN THE 20S. ITS LOOKING LIKE A HARD FREEZE FOR MOST OF
THE FCST AREA XCPT FOR THE URBAN DOWNTOWNS AND COMMUNITIES NEAR THE
BAY. THAT LIKELY WL MARK THE END OF THE GROWING SEASON FOR MUCH OF
THE AREA.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
THE HIGH SLIDES SOUTHEAST ACROSS THE CAROLINAS AND NEAR THE
SOUTHEAST COAST MONDAY AND MONDAY NIGHT. TEMPERATURES WILL MODIFY
SOME DURING THE DAY BUT REMAIN A LITTLE ON THE CHILLY SIDE MONDAY
NIGHT.

HIGH PRESSURE SLIDES OFFSHORE TUESDAY THROUGH WEDNESDAY NIGHT TO
ALLOW A COLD FRONT TO GRADUALLY SLIDE INTO THE REGION AND BRING A
CHANCE FOR RAIN SHOWERS. PRECIP TIMING HAS BEEN PUSHED BACK TO
WED-WED NIGHT. HIGH PRESSURE WILL BUILD ON THURSDAY.

&&

.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
A LOW PRESSURE SYSTEM WILL APPROACH FROM THE WEST TODAY AND TONIGHT.
ANY PRECIPITATION SHOULD STAY WEST OF THE TAF SITES THROUGH MOST
OF THIS PERIOD. A VFR CEILING MAY BE PREVALENT WITH VERY FEW
BREAKS WITH THE APPRAOCHING SYSTEM.

LOW PRESSURE STRENGTHENS OFF THE COAST ON SATURDAY. NORTHERLY
WINDS WILL GUST UP TO 20-25 KT AND MVFR CEILINGS WILL BE POSSIBLE
WITH SHOWERS.

WINDS WL PROVIDE PRIMARY OP IMPACT SAT NGT-SUN...AS AN ELEVATED CORE
OF 40+ KT WNDS CROSS TERMINALS. THE LLJ WL RESIDE ABT 2K FT ABV SFC.
SHUD HV 25-30KT GUSTS IN NW FLOW AT GRND LVL...MAYBE A LTL HIER THAN
THAT SUN MRNG-MIDDAY. ANY CIGS WUD BE MVFR-VFR SAT NGT AND SHUD CLR
BY/SOON AFTR SUNRISE SUN MRNG.

VFR SUN AFTN INTO TUE.

&&

.MARINE...

EAST TO NORTHEAST WINDS UNDER SMALL CRAFT CONDITIONS WILL PREVAIL
TODAY AND TONIGHT AS A LOW PRESSURE SYSTEM PASSES WEST AND SOUTH OF
THE AREA.

WITH THE STRENGTHENING LOW MOVING OFF THE COAST ON SATURDAY...SMALL
CRAFT CONDITIONS WILL BE MET WITH NORTHERLY WINDS GUSTING TO
AROUND 30 KT.

GRADIENT INCREASES SAT NGT. AM NOT CERTAIN IF GALE CONDITIONS WL
ENCOMPASS ENTIRE MARINE AREA...BUT IT SHUD HIT A MAJORITY OF IT.
CONDS WOULD CONT INTO SUN BEFORE THE GRADIENT RELAXES AND WNDS
SUBSIDE. SCA CONDS PROGGED TO HOLD ON THRU SUN NGT PER CURRENT
FCST.

AS HIPRES BLDS ELY NEXT WEEK...NO HAZARDS EXPECTED AT THAT TIME.

&&

.TIDES/COASTAL FLOODING...

A DEEP AREA OF LOW PRESSURE WILL CROSS THE CAROLINAS SATURDAY
MORNING AND THEN TRACK NORTHEAST ALONG THE MID-ATLANTIC COAST
SATURDAY NIGHT. POSITIVE DEPARTURES UP TO A HALF FOOT ON THE
WATERS ATTM...AND THESE MAY INCREASE A LITTLE BIT MORE THROUGH
TONIGHT. TIDAL FLOODING ISSUES WOULD ONLY OCCUR IF DEPARTURES
EXCEEDED A FOOT. AT THIS POINT...SUSPECT THAT WONT HAPPEN.

BLOWOUT CONDITIONS ARE EXPECTED SAT AFTERNOON THROUGH SUNDAY.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 8 AM TO 8 PM EDT SATURDAY FOR
     ANZ530>543.

&&

$$
UPDATE...WOODY!
PRVS...HTS/ADS







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