Heavy Snow in Pennsylvania, March 1, 2005

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
900 PM EST MON FEB 28 2005

EVENING DISC:

GOING TO LEAVE THE WARNINGS AS IS ALTHOUGH THE SNOW HAS BEEN SLOW TO
ACCUMULATE UP NORTH. STILL MORE UPSTREAM TO BRING A 1 AN HOUR FOR SOME
OF THOSE AREAS TO THE NORTH. HAVE KEEP THE ADVISORY IN THE SOUTHERN
AREAS IN EFFECT UNTIL MIDNIGHT. THE PCPN MOVING THROUGH THE EASTERN
SHORE AND DELAWARE/SNJ IS RATHER JUICY WITH EVEN REPORTS OF FREEZING
RAIN SLEET ALONG WITH HEAVIER SNOW. BWI HAS PICKED UP AN INCH AN
HOUR ON LATEST ASOS OB. THE BACK EDGE(PROVIDED NOTHING ELSE FORMS)
WIL BE REACH THE CENTRAL DELAWARE BAY BY AROUND 1015 PM AND CONTINUE
MOVING TO THE NORTHEAST BEFORE MIDNIGHT. AT SUCH TIME WILL HAVE TO
UPDATE THE TO POSSIBLY LOWER THE ADVISORY. HAVE SENT SEVERAL PNSS
FOR SNOW AND AMOUNTS ARE HIGHEST IN THE DELAWARE VALLEY
REGION.

SFC LOW HAS BEEN MOVING ALONG AT 040 DEGREE TRACK AT ROUGHTLY 32 MPH SINCE
18Z AND IS NOW(BASED ON 00Z ANALYSIS) 193 MILES SE OF ATLANTIC CITY.

PRECIPITATION ASSOCIATED WITH OTHER LOW IN THE OHIO VALLEY HAS BEEN
ROTATING THROUGH THE MIDDLE PART OF PA AND HAS SHOWN SIGNS OF DRYING
OUT OVER THE APPALACHIANS. THERE WILL BE SNOW FALLING BUT OF A
LESSER INTENSITY.

SAFE TO SAY THAT TRAVEL ON SECONDARY ROADS WILL BE VERY TOUGH
OVERNIGHT AND NEEDLESS TO SAY TO USE EXTREME CAUTION.

TIDES HAVE BULGED TO 1.6 ABOVE NORMAL WHICH IS IN THE MINOR FLOODING
ESPECIALLY WITH THE HEAVY WAVE ACTION OF 17 FT OUT AT BUOY 44009.

EBERWINE

*****
.SHORT TERM (TONIGHT THROUGH WEDNESDAY)...
AT 430 PM, THE CENTER OF THE LOW WAS LOCATED ABOUT 175 MILES EAST OF
THE VIRGINIA CAPES.  THE STORM WILL CONTINUE TO MOVE TO THE
NORTHEAST AND ITS CENTER SHOULD PASS VERY NEAR CAPE COD AROUND
DAYBREAK ON TUESDAY.

BASED ON THE TRACK OF THE STORM, THE PRECIP TYPE SHOULD REMAIN SNOW
EXCEPT IN THE COUNTIES RIGHT ALONG THE COAST.  IN THOSE COUNTIES
THERE WILL CONTINUE TO BE SLEET AND RAIN AS WELL.

THE HEAVIEST OF THE PRECIP WAS WORKING ITS WAY UP THROUGH SOUTHERN
MARYLAND AND SOUTHERN DELAWARE AT 430 PM.  THE HEAVY PRECIP WILL
CONTINUE TO DRIFT TO THE NORTH AND IT SHOULD MOVE ACROSS THE PHL
METRO AREA BETWEEN ABOUT 6 AND 10 PM.

WELL TAPER THE PRECIP TO SNOW SHOWERS FROM SOUTH TO NORTH DURING
THE LATE EVENING AND OVERNIGHT HOURS, EXCEPT IN OUR NORTHERN
COUNTIES WHERE THE STEADY SNOW SHOULD LINGER INTO TUESDAY MORNING.

WEVE MADE SOME MINOR ADJUSTMENTS TO SNOW AMOUNTS AND TO THE
WARNINGS AND ADVISORIES, BUT NOTHING EARTH SHATTERING.  THE
FORECASTS AND STATEMENTS HAVE ALREADY BEEN ISSUED.

THE NORTHERN BRANCH MID LEVEL LOW CONTINUES TO BE FORECAST TO PASS
ACROSS OUR REGION ON TUESDAY AND IT WILL LIKELY MOVE AWAY TO OUR
NORTHEAST ON TUESDAY NIGHT.  THAT FEATURE SHOULD BRING A CHANCE OF
LINGERING SNOW AND SNOW SHOWERS THROUGH TUESDAY, AND INTO TUESDAY
NIGHT IN OUR NORTHERN COUNTIES.

&&

.LONG TERM (WEDNESDAY NIGHT THROUGH MONDAY)...
OTHER THAN A CLIPPER TYPE SYSTEM EXPECTED ON SATURDAY EVENING IT
APPEARS AS THOUGH THE PERIOD FROM WEDNESDAY NIGHT THROUGH MONDAY
WILL BE COLD BUT RELATIVELY UNEVENTFUL.  THE LONG WAVE TROUGH WILL
CONTINUE TO INFLUENCE THE NORTHEASTERN STATES.

&&

.AVIATION...
CONDITIONS HAVE DETERIORATED TO IFR AT THE TAF SITES...WITH RESPECT
TO EITHER VISIBILITY OR CEILING OR BOTH.  IFR OR LIFR SHOULD
CONTINUE FOR THE FIRST HALF OF THE TAF VALID PERIOD WITH THE
EXCELLENT LOW LEVEL FORCING AND STRONG UPWARD VERTICAL MOTIONS
ASSOCIATED WITH THE VERY DYNAMIC COASTAL LOW AND INTERACTING
NEGATIVELY TILTED UPPER LEVEL TROUGH.  AFTER THE LOW MOVES NORTH
PAST OUR LATITUDE LATER TONIGHT, WE EXPECT THE BACKING WINDS TO
BRING SOME IMPROVEMENT FOR THE SOUTHERN AND CENTRAL TAF SITES TOWARD
OR AFTER MIDNIGHT, WITH OCCASIONAL FLURRIES OR SNOW SHOWERS IN THE
WAKE OF THE STORM OVERNIGHT AND TUESDAY MORNING.  FOR ACY AND MIV,
THE LOW LEVEL WINDS AND THICKNESS VALUES AUGUR FOR MIXED PRECIP,
ESPECIALLY AT ACY.  FURTHER NORTH FOR ABE AND RDG, IFR OCCASIONALLY
MVFR WITH MORE IN THE WAY OF LIGHT SNOW OR SNOW SHOWERS IS FORECAST
TOWARD MORNING.

&&

.MARINE...
WE WILL CONTINUE ALONG WITH THE PREVIOUS FORECASTS OF STORM WARNINGS
ON THE COASTAL WATERS AND A GALE WARNING ON DE BAY.  BOTH THE 12Z
NAM AND GFS SHOW THE BETTER BOUNDARY LAYER WINDS JUST EAST OF THE
COAST. HOWEVER, NOW THAT EVEN THE NAM IS A TAD FURTHER EAST WITH THE
SURFACE LOW TRACK, OUR COASTAL WATERS MAY HAVE A BETTER GRADIENT FOR
A LONGER TIME, MAINLY IMPACTING COASTAL FLOOD EFFECTS (SEE BELOW).
WAVEWATCH BUILDS SEAS TO 12 FT TONIGHT, AND THIS IS ACCEPTED.

&&

.TIDES...
WITH THE LOW A BIT FURTHER EAST, ONE WOULD EXPECT SLIGHTLY STRONGER
ONSHORE WINDS FOR A BIT LONGER DURATION.  HOWEVER, THE 12Z NGM STORM
SURGE GUIDANCE CONTINUES THE TWO AND A HALF FOOT ANOMALIES, WITH THE
AVN SURGE GUIDANCE LAGGING A HALF FOOT OR MORE. SO, WE WILL CONTINUE
TO FORECAST A WIDESPREAD HIGH END MINOR TIDAL FLOODING EVENT, WITH
LOCALIZED MODERATE ESPECIALLY NORTH ALONG THE NJ COAST TONIGHT.  THE
SPECIAL WEATHER STATEMENT SPSPHI WILL BE REFRESHED.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WINTER STORM WARNING OVERNIGHT AND TUE MORNING
     ZONES PAZ054-055-060>062.
     WINTER STORM WARNING OVERNIGH ZONES PAZ067>071.
     NJ...WINTER STORM WARNING OVERNIGHT AND TUE MORNING
     ZONES NJZ001-007-008.
     WINTER STORM WARNING OVERNIGHT
     ZONES NJZ009-010-012-013-015>019.
     WINTER WEATHER ADVISORY OVERNIGHT ZONES
     NJZ014-020-026-027.
     WINTER WEATHER ADVISORY TIL MIDNIGHT
     ZONES NJZ021-022.
DE...WINTER STORM WARNING OVERNIGHT ZONE DEZ001.
     WINTER WEATHER ADVISORY TIL MIDNIGHT ZONE DEZ002.
MD...WINTER STORM WARNING OVERNIGHT ZONE MDZ008.
     WINTER WEATHER TIL MIDNIGIHT ZONES MDZ012-015-019-020.
MARINE...GALES NOW UP ON OCEAN ANZ450>455.
         SCA ON UPPER BAY ANZ430 AND GALES ON ANZ431 LOWER BAY.

&&

SHORT TERM/LONG TERM...IOVINO/EBERWIWNE