Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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FXUS61 KPHI 041408
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
908 AM EST WED MAR 4 2015

.SYNOPSIS...
A COLD FRONT...ATTACHED TO LOW PRESSURE ACROSS CANADA...WILL
CROSS THE AREA TODAY AND STALL TO THE SOUTH TONIGHT. LOW PRESSURE
WILL MOVE ALONG THE FRONT TONIGHT THROUGH THURSDAY NIGHT. HIGH
PRESSURE WILL BUILD IN FOR FRIDAY AND SATURDAY. A WEAK DISTURBANCE
WILL PASS NORTH OF THE AREA SATURDAY NIGHT. MORE HIGH PRESSURE
WILL ARRIVE FOR EARLY NEXT WEEK.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
930 AM EST UPDATE...NOT MANY CHANGES IN THE NEAR TERM EXCEPT TO
EXPIRE THE WINTER WEATHER ADVISORY IN THE POCONOS AND NORTHWEST
NEW JERSEY. TEMPERATURES ARE ABOVE FREEZING IN THESE AREAS AND THE
PRECIPITATION IS ALL RAIN AT THIS POINT. HAVE KEPT THE WINTER
STORM WATCH GOING FOR THESE LOCATIONS AS I WOULD LIKE TO TAKE A
LOOK AT THE 12Z MODELS BEFORE DECIDING ON ANY CHANGES FOR THE
WINTER WEATHER HEADLINES FOR TONIGHT AND TOMORROW.

PREVIOUS NEAR TERM DISCUSSION...A COLD FRONT WILL DROP SLOWLY
THROUGH OUR REGION FROM THE NORTHWEST TODAY. LOW PRESSURE IS
FORECAST TO DEVELOP ALONG THE BOUNDARY IN THE SOUTHEASTERN STATES
AND IT SHOULD BE LOCATED IN NORTH CAROLINA BY EVENING.

LOW LEVEL MOISTURE WILL LINGER IN OUR REGION TODAY WITH
OCCASIONAL RAIN. TEMPERATURES WILL REMAIN BELOW FREEZING IN SPOTS
IN THE POCONOS AND IN FAR NORTHERN NEW JERSEY EARLY THIS MORNING.
AS A RESULT, A WINTER WEATHER ADVISORY WILL REMAIN IN PLACE FOR
PATCHY FREEZING RAIN AND FREEZING DRIZZLE THERE.

TEMPERATURES ARE FORECAST TO REMAIN IN THE 30S IN OUR NORTHERN
COUNTIES FOR TODAY AND THEY SHOULD RISE INTO THE 40S IN THE SOUTH.
A LIGHT SOUTHWEST WIND IS ANTICIPATED TO BECOME WEST THEN
NORTHWEST.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
THE COLD FRONT WILL CONTINUE TO SINK SLOWLY TO OUR SOUTH DURING
TONIGHT AND THURSDAY AS WAVES OF LOW PRESSURE MOVE ALONG IT.
ARCTIC AIR WILL BEGIN TO FILTER INTO OUR REGION FROM THE NORTHWEST
AS PRECIPITATION RIDES NORTHEASTWARD ALONG THE FRONT. WE CONTINUE
TO EXPECT A SIGNIFICANT SNOWFALL FOR OUR FORECAST AREA.
TEMPERATURES ARE ANTICIPATED TO FALL THROUGH THE 30S TONIGHT AND
INTO THE 20S FOR THURSDAY IN MUCH OF OUR REGION.

PERIODS OF RAIN WILL TRANSITION THROUGH SLEET TO SNOW FROM NORTH
TO SOUTH IN OUR REGION TONIGHT. THE PRECIPITATION TYPE SHOULD BE
ALL SNOW IN OUR REGION FOR THURSDAY.

WE HAVE UPGRADED THE WINTER STORM WATCH TO A WINTER STORM WARNING
FOR ALL BUT THE LEHIGH VALLEY, THE POCONOS AND NORTHERN NEW
JERSEY.

WE ARE ANTICIPATING SNOWFALL TOTALS GENERALLY IN THE 5 TO 9 INCH
RANGE IN THE WARNING AREA BASED ON THE LATEST GUIDANCE. WE MAY SEE
SLIGHTLY LOWER AMOUNTS IN SOUTHERN DELAWARE, PERHAPS IN THE 3 TO 7
INCH RANGE.

THERE REMAINS SOME UNCERTAINTY AS TO WHETHER OUR NORTHERN
COUNTIES WILL REACH THEIR 6 INCH SNOWFALL CRITERION FOR A WARNING.
WE WILL KEEP THE WINTER STORM WATCH GOING THERE FOR A BIT LONGER.

THE SNOW IS ANTICIPATED TO END FROM NORTHWEST TO SOUTHEAST ON
THURSDAY AFTERNOON AS DRY AIR BEGINS TO BUILD INTO OUR REGION.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
THE END OF THE STORM EARLY THURSDAY NIGHT WITH THE STEADY SNOWS
MOVING OFF THE E/SE AREAS EARLY. A CHC POP FOR THE BEGINNING FEW
HOURS OF THE OVERNIGHT PERIOD. CLEARING ADVANCES FROM N/W TO S/E
OVERNIGHT. COLD WITH LOWS IN THE SINGLE DIGITS MOST AREAS. WIND
CHILLS BELOW ZERO BY DAWN...PERHAPS AS LOW AS -12 TO -15 FAR
NORTH.

FRI/FRI NIGHT...FAIR WEATHER WITH HIGH PRESSURE ACROSS THE AREA.
TEMPERATURES REMAIN SOLIDLY BELOW NORMAL. HIGHS IN THE MID/UPPER
20S. NORMAL HIGHS FOR EARLY MARCH ARE 20 OR SO DEGREES ABOVE THAT.

SAT/SAT NIGHT...FAIR WEATHER ACROSS MOST AREAS. A FEW SNOW
SHOWERS POSSIBLE ACROSS THE SOUTHERN POCONOS. TEMPERATURES
MODERATING...BUT STILL 10 OR SO DEGREES BELOW NORMAL.

SUN/SUN NIGHT...FAIR WEATHER WITH TEMPS A LITTLE BELOW NORMAL.

MON/MON NIGHT...FEW SNOW SHOWERS POSSIBLE EARLY WITH A WEAK
LOW/FRONT CROSSING THE REGION. POPS IN THE SLGT CHC RANGE ATTM.
TEMPS SLIGHTLY BELOW NORMAL. FAIR WEATHER MON NIGHT.

TUE...FAIR WEATHER WITH TEMPS NEAR NORMAL. HIGHS CLOSE TO 50
DEGREES POSSIBLE ACROSS THE DELMARVA AND METRO PHILLY.

&&

.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

CEILINGS MAY VARY BETWEEN MVFR AND VFR FOR MOST OF THE
REGION, ALTHOUGH KACY AND KMIV MAY SEE MAINLY IFR, THIS MORNING.
VISIBILITIES SHOULD REMAIN MVFR. HOWEVER, BY MID AFTERNOON,
CEILINGS SHOULD SETTLE BACK INTO IFR AS SOMEWHAT MILD AIR SETTLES
OVER THE COLD GROUND AND ADDITIONAL RAIN SPREADS OVER OUR REGION.

CONDITIONS SHOULD BE IFR FOR TONIGHT AS RAIN BECOME STEADIER THIS
EVENING. COLD AIR WILL BUILD DOWN FROM THE NORTHWEST AND NORTH AND
THE RAIN WILL TRANSITION THROUGH SLEET TO SNOW. A SIGNIFICANT SNOW
ACCUMULATION IS ANTICIPATED FOR WEDNESDAY NIGHT INTO THURSDAY AND
IT WILL HAVE AN IMPACT ON THE AIRFIELDS.

A LIGHT WIND SHOULD VEER FROM THE SOUTHWEST TO THE NORTHWEST
TODAY. THE WIND IS FORECAST TO FAVOR THE NORTHWEST AND NORTH FOR
TONIGHT AROUND 6 TO 12 KNOTS.

OUTLOOK...

THURSDAY...IFR WITH SIGNIFICANT SNOWFALL.

THURSDAY NIGHT...CONDITIONS RETURNING TO VFR OVERNIGHT.

FRIDAY THRU SUNDAY...MOSTLY VFR.

&&

.MARINE...
A SOUTHWEST WIND AROUND 10 TO 15 KNOTS WITH GUSTS AROUND 20 KNOTS
THIS MORNING SHOULD BACK TO THE WEST, THEN TO THE NORTHWEST AROUND
10 KNOTS TODAY AS A COLD FRONT SINKS THROUGH OUR REGION. THE WIND
IS EXPECTED TO SETTLE INTO THE NORTHWEST AND NORTH FOR TONIGHT
AROUND 10 TO 15 KNOTS. WINDS WILL INCREASE AFTER MIDNIGHT. THUS A
SMALL CRAFT ADVISORY HAS BEEN ISSUED BEGINNING 4 AM TOMORROW
MORNING, CONTINUING THROUGH THE DAY TOMORROW. THE SCA MAY NEED TO
BE EXTENDED LATER.

OUTLOOK..

THU NIGHT...SCA WINDS AND SEAS EXPECTED.

FRI THRU SUN...MOSTLY SUB-SCA CONDITIONS.

&&

.HYDROLOGY...
PLEASE MONITOR LATEST QPF FCSTS FROM WPC AND MARFC.

THE FORECASTS CONTINUE TO SHOW A DECENT AMOUNT OF QPF ACROSS THE
AREA TONIGHT AND INTO THURSDAY. A CHANGEOVER TO SLEET OR SNOW
ISN`T EXPECTED TO OCCUR UNTIL EARLY THURSDAY MORNING ACROSS THE
SOUTHERN AREAS.

WHILE THERE ISN`T MUCH OF A SNOWPACK ACROSS THE SOUTHERN HALF OF
OUR CWA, THE GROUND IS FROZEN, AND ANY RUNOFF WILL BE VERY
EFFICIENT.

IF THE 0.75 TO 1.00 INCHES OF QPF MATERIALIZES, WE FEEL NUISANCE
POOR DRAINAGE AND LOW LYING FLOODING WILL BE THE MOST LIKELY
OUTCOME. MODELED SOLUTIONS SUGGEST WE WOULD NEED ABOUT 2.50 INCHES
OF LIQUID, EITHER IN THE FORM OF ALL RAIN OR RAIN AND MELTING SNOW
TO HAVE OUR SOUTHERN CREEKS AND STREAMS LEAVE THEIR BANKS.

WITH MORE SNOW OR SLEET EXPECTED ACROSS THE NORTHERN HALF OF THE
CWA, WE`RE NOT CONCERNED ABOUT FLOODING THERE.

WITH THE RAINFALL, THE FLOW ON AREA CREEKS AND STREAMS WILL
INCREASE. THIS COULD START TO MOVE ICE, AND IN A WORST CASE
SCENARIO, CREATE RESTRICTIONS OR JAMS.

CONTINUE TO MONITOR THE FORECAST. KEEP IN MIND THAT SNOWMELT AND
THE WARMER TEMPERATURES EXPECTED TODAY, BY THEMSELVES, WOULD NOT
CAUSE FLOODING. THE AMOUNT OF RAIN THAT WE RECEIVE WILL BE THE
DETERMINING FACTOR.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WINTER STORM WATCH FROM 7 PM EST THIS EVENING THROUGH THURSDAY
     EVENING FOR PAZ054-055-061-062.
     WINTER STORM WARNING FROM 7 PM THIS EVENING TO 7 PM EST
     THURSDAY FOR PAZ060-101>106.
     WINTER STORM WARNING FROM 11 PM THIS EVENING TO 7 PM EST
     THURSDAY FOR PAZ070-071.
NJ...WINTER STORM WATCH FROM 7 PM EST THIS EVENING THROUGH THURSDAY
     EVENING FOR NJZ001-007-008.
     WINTER STORM WARNING FROM 7 PM THIS EVENING TO 7 PM EST
     THURSDAY FOR NJZ009-010-012-015.
     WINTER STORM WARNING FROM 11 PM THIS EVENING TO 7 PM EST
     THURSDAY FOR NJZ013-014-016>027.
DE...WINTER STORM WARNING FROM 11 PM THIS EVENING TO 7 PM EST
     THURSDAY FOR DEZ001-002.
     WINTER STORM WARNING FROM 3 AM TO 7 PM EST THURSDAY FOR DEZ003-
     004.
MD...WINTER STORM WARNING FROM 11 PM THIS EVENING TO 7 PM EST
     THURSDAY FOR MDZ008-012-015-019-020.
MARINE...SMALL CRAFT ADVISORY FROM 4 AM TO 7 PM EST THURSDAY FOR
     ANZ450>455.

&&

$$
SYNOPSIS...O`HARA
NEAR TERM...IOVINO/JOHNSON
SHORT TERM...IOVINO
LONG TERM...O`HARA
AVIATION...IOVINO/JOHNSON/O`HARA
MARINE...IOVINO/JOHNSON/O`HARA
HYDROLOGY...KRUZDLO



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