Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000
FXUS61 KPHI 271618 AAA
AFDPHI

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1118 AM EST THU NOV 27 2014

.SYNOPSIS...
HIGH PRESSURE WILL BUILD TOWARD THE REGION TODAY, BUILDING ACROSS
THE EASTERN UNITED STATES THROUGH FRIDAY BEFORE SLIDING TO THE
SOUTH AND EAST LATER ON SATURDAY. A COLD FRONT WILL SLOWLY MOVE
TOWARDS THE REGION SUNDAY NIGHT AND CROSS THE AREA MONDAY INTO
MONDAY NIGHT. HIGH PRESSURE WILL RETURN FOR TUESDAY WITH ANOTHER
FRONTAL SYSTEM EXPECTED TO ARRIVE ON WEDNESDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
WE RECEIVED A SNOWFALL REPORT OF 2 INCHES IN LAKE HARMONY AROUND
1030 AM (NEAR THE CARBON/MONROE BORDER AT AN ELEVATION OF 1800 FT
ASL). IT IS ONE OF THE HIGHEST ELEVATIONS IN OUR CWA, SO MOST
LOCATIONS IN THE OUR NORTHERN-MOST LOCATIONS WILL HAVE MUCH LESS
SNOWFALL ACCUMULATION AS TEMPS ARE CLOSER TO FREEZING AND THE SNOW
SHOWERS WILL BE LIGHTER IN INTENSITY ON THE LEEWARD SIDE OF THE
POCONOS. PUSHED OUT A SNOWFALL MAP ON THE WEBSITE FOR TODAY. THE
MAP ALSO INCLUDES WHAT HAS ALREADY FALLEN THIS MORNING.

940 AM DISCUSSION...
THE COASTAL STORM THAT BROUGHT WINTRY WEATHER TO THE NORTHWESTERN
HALF OF THE FORECAST AREA YESTERDAY IS NOW A 990 MB SURFACE LOW NEAR
NOVA SCOTIA. THIS MORNING`S WATER VAPOR SATELLITE LOOP SHOWS THE
UPPER TROUGH ASSOCIATED WITH THIS SYSTEM CARVED OUT OVER THE EASTERN
UNITED STATES. A COUPLE OF WEAK SHORTWAVE DISTURBANCES ROTATING
AROUND THE UPPER TROUGH WILL MOVE THROUGH THE MID-ATLANTIC REGION
TODAY.

THE FIRST SHORTWAVE TROUGH IS CURRENTLY MOVING THROUGH EASTERN PA
THIS MORNING AND IS RESPONSIBLE FOR SCATTERED SNOW SHOWERS ACROSS
THE LEHIGH VALLEY, THE POCONOS, NORTHWEST NEW JERSEY AS WELL AS A
FEW FLURRIES TO CENTRAL NEW JERSEY. THIS DISTURBANCE WILL BE SLOW TO
LIFT NORTHEASTWARD TODAY, SO LIGHT SNOW SHOWERS AND FLURRIES MAY
LINGER ACROSS NORTHEASTERN PA/NORTHERN NJ INTO THE FIRST PART OF THE
AFTERNOON. LIGHT SNOWFALL ACCUMULATIONS ARE POSSIBLE IN THE HIGHER
ELEVATIONS, WHERE TEMPERATURES ARE BELOW FREEZING. TEMPERATURES ARE
AT OR ABOVE FREEZING IN THE VALLEYS, SO DO NOT EXPECT ANY
ACCUMULATION THERE.

THE SECOND SHORTWAVE TROUGH IS CURRENTLY OVER CENTRAL VA THIS
MORNING. THIS SYSTEM WILL MOVE EASTWARD ACROSS THE DELMARVA LATER
TODAY. MODELS IN AGREEMENT WITH THE BULK OF THE SHOWER ACTIVITY
STAYING SOUTH OF OUR AREA, BUT ISOLATED SHOWERS MAY BRUSH SOUTHERN
DE AND ADJACENT PARTS OF EASTERN MD THIS AFTERNOON.

A PUSH OF COLDER AIR INTO THE REGION IN WAKE OF YESTERDAY`S COASTAL
LOW AND CLOUD COVER OVER THE AREA WILL RESULT IN MAX TEMPS ABOUT 10
DEGREES BELOW NORMAL (MID TO UPPER 30S WEST OF THE FALL LINE / LOWER
TO MID 40S TO THE EAST).

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/...
A MID LEVEL SHORT WAVE TRAVELING IN THE BROAD LONG WAVE TROUGH
SHOULD PASS OVER OUR REGION TOWARD DAYBREAK ON FRIDAY. WHILE MUCH
OF THE STRATOCUMULUS OVER OUR AREA SHOULD DISSIPATE THIS EVENING,
THE SHORT WAVE IS EXPECTED TO KEEP HIGH CLOUDS AND PERHAPS SOME
MID LEVEL CLOUDS OVERHEAD.

A LIGHT WEST NORTHWEST WIND IS EXPECTED TO CONTINUE INTO TONIGHT.
TEMPERATURES ARE FORECAST TO DROP INTO THE TEENS UP NORTH AND INTO
THE 20S ELSEWHERE. WE WENT A BIT BELOW THE FORECAST GUIDANCE
VALUES WHERE THE SNOW PACK IS EXPECTED TO LINGER.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
FRIDAY...COLD AIR SETTLES IN FOR FRIDAY AS HIGH PRESSURE STARTS
TO BUILD INTO OUR AREA. HIGHS WILL A FEW DEGREES COLDER THAN
THURSDAY BUT THE SUN SHOULD BE SHINING ACROSS THE REGION THROUGH
THE DAY. SEVERAL WAVES ROTATE THROUGH THE MID LEVELS AND MAY SPARK
OFF A FEW LIGHT SNOW SHOWERS ACROSS THE NORTHWESTERN AREAS.
LIMITING FACTOR IS JUST HOW MUCH MOISTURE WILL BE AROUND TO TAP
INTO AS IT LOOKS LIKE WE WILL BE FAIRLY DRY DURING THE DAY. WILL
KEEP A MENTION OF SOME ISOLATED SNOW SHOWERS IN THE SOUTHERNS
POCONOS FOR FRIDAY NIGHT AT THIS TIME. CLOUDS WILL START TO MOVE
ACROSS THE AREA FRIDAY NIGHT AND DEPENDING ON HOW FAST WE CLOUD
UP, WE MAY SEE SLIGHTLY WARMER LOWS. FRIDAY NIGHT TEMPERATURES
WILL REMAIN COLD AND DROP DOWN INTO 20S WITH TEENS ACROSS THE
HIGHER TERRAIN.

SATURDAY...THE AIR MASS STARTS TO MODIFY AS THE HIGH BUILDS ACROSS
THE EAST COAST AND THEN GRADUALLY SLIDES TO THE SOUTH AND EAST
THROUGH THE AFTERNOON AND EVENING. TEMPERATURES WILL BE SLIGHTLY
WARMER THAN ON FRIDAY AND AND ANOTHER DRY DAY SHOULD BE IN STORE
FOR THE AREA. AREAS ACROSS THE HIGHER TERRAIN WILL REMAIN COLDER
AND SOME SPOTS MAY STRUGGLE TO GET ABOVE THE FREEZING MARK.
SHORTWAVES EMBEDDED IN THE MID LEVEL FLOW WILL ROTATE THROUGH OUR
AREA AND THERE REMAINS A CHANCE SOME LIGHT SNOW SHOWERS MAY OCCUR
OVER THE HIGHER TERRAIN AND WE WILL CONTINUE TO MENTION SOME
ISOLATED SNOW SHOWERS IN THAT AREA.

THE HIGH SHIFTS TO THE SOUTH AND EAST BY SATURDAY NIGHT AND WE
SHOULD BE ABLE TO REMAIN A BIT WARMER THROUGH THE OVERNIGHT HOURS
AS WE HAVE A BUILDING SOUTHERLY FLOW AND INCREASING CLOUD COVER.
LOWS WILL GENERALLY BE IN THE 30S, WARMER ALONG THE COAST.

SUNDAY...SKIES CONTINUE TO CLOUD UP IN ADVANCE OF THE APPROACHING
COLD FRONT AS WARMER AND MOISTER AIR OVERSPREADS OUR AREA. WHILE
SUNDAY LOOKS TO BE A MOSTLY DRY DAY, SOME SHOWERS MAY DEVELOP IN
ADVANCE OF THE FRONT AS YET ANOTHER SHORTWAVE MOVES ACROSS THE
AREA. HIGHS WILL REACH INTO THE UPPER 40S TO LOWER 50S, WITH LOW
TO MOD 40S ACROSS THE HIGHER TERRAIN.

MONDAY...MODEL GUIDANCE CONTINUES TO SHOW THE FRONT SLOWLY
DROPPING DOWN THROUGH THE AREA ON MONDAY, PUSHING OFFSHORE MONDAY
NIGHT. MOISTURE IS LIMITED AS THE FRONT MOVES INTO OUR AREA BUT
SOME RAIN/SNOW SHOWERS REMAIN POSSIBLE. WITH THE FRONT TAKING ITS
TIME, HIGHS WILL BE IN 40S TO 50S ACROSS THE AREA BEFORE COLDER
AIR ONCE AGAIN MOVES IN. BEHIND THE FRONT, WE WILL SEE THE COLD
AIR MOVE IN AND OVERNIGHT LOWS ARE EXPECTED TO DROP INTO THE 20S
TO LOWER 30S ACROSS THE AREA.

TUESDAY...AS THE FRONT MOVES OFFSHORE, ANY LINGERING
PRECIPITATION WILL END FROM NORTHWEST TO SOUTHEAST. A FEW LIGHT
SHOWERS MAY STILL BE AROUND EARLY TUESDAY BEFORE CLEARING OCCURS.
HIGH PRESSURE BUILDS IN FROM THE WEST AND THEN SLIDES ACROSS TO
THE NORTH OF THE AREA TUESDAY. MAXIMUM TEMPERATURES WILL BE ABOUT
5 TO 10 DEGREES COLDER THAN ON MONDAY.

WEDNESDAY...ANOTHER FRONTAL SYSTEM MAKES ITS WAY TOWARD OUR AREA
AND IT LOOKS LIKE IT WILL MOVE INTO OUR AREA ON WEDNESDAY.
DIFFERING OPINIONS IN THE GUIDANCE AT THIS TIME WITH RESPECT TO
TIMING, MOISTURE AND POSITION OF THE BOUNDARY AS IT CROSSES THE
AREA. WILL CONTINUE TO MENTION PRECIPITATION IN THE FORECAST.

&&

.AVIATION /16Z THURSDAY THROUGH MONDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

LIGHT SNOW SHOWERS AND FLURRIES ASSOCIATED WITH AN UPPER
DISTURBANCE IS CURRENTLY MOVING THRU ABE AND TTN. EXPECT THE LAST
OF THIS ACTIVITY TO END AT TTN IN BEFORE 16Z AND ABE BY 17Z,
RESULTING IN MVFR CIGS AND TEMPO MVFR-IFR VSBYS. CLEARING JUST
UPSTREAM OF PHL AND PNE SHOULD ALLOW THESE TERMINALS THE BKN MVFR
CIGS AROUND 3000 FT TO SCT OUT LATE THIS MORNING. HOWEVER, LATEST
HRRR/RAP FORECAST SOUNDINGS, WHICH HAS CAPTURED THIS FIRST ROUND
OF LOWER CIGS, SHOWS ENOUGH DAYTIME MIXING AND CAA ALOFT FOR
STRATOCU TO REDEVELOP AROUND 2500 FT BY AROUND 18-19Z. THE OTHER
TERMINALS SHOULD REMAIN VFR TODAY WITH A FAIR AMOUNT OF
STRATOCUMULUS OVERHEAD WITH BASES ABOVE 4000 FEET. A RELATIVELY
LIGHT WEST NORTHWEST WIND IS EXPECTED THROUGH THE TAF PERIOD.
SPEEDS SHOULD FAVOR THE 5 TO 10 KNOT RANGE.

VFR TONIGHT AS STRATOCU DIMINISHES. SHOULD STILL SEE MID TO HI
CLOUDS OVERHEAD.

OUTLOOK...
FRIDAY...VFR CONDITIONS EXPECTED WITH NORTHWEST WINDS GUSTING UP
TO 20 KNOTS.

SATURDAY...VFR CONDITIONS EXPECTED WITH SOUTHWEST WINDS AROUND 10
TO 15 KNOTS.

SUNDAY...VFR CONDITIONS EXPECTED WITH SOUTHWEST WINDS AROUND 10
TO 15 KNOTS.

MONDAY...VFR CONDITIONS EXPECTED WITH NORTHWEST WINDS GUSTING UP
TO 20 KNOTS.

&&

.MARINE...
AS THE LOW CONTINUES TO MOVE ACROSS NOVA SCOTIA THIS MORNING,
WIND SPEEDS ARE ON THE DECREASE ON OUR COASTAL WATERS. WAVE
HEIGHTS REMAIN ELEVATED ON OUR OCEAN WATERS AND THEY WILL TAKE
SOME TIME TO FALL BACK BELOW 5 FEET. AS A RESULT, THERE IS A SMALL
CRAFT ADVISORY FOR HAZARDOUS SEAS IN EFFECT UNTIL 400 PM.

AN APPROACHING MID LEVEL SHORT WAVE MAY CAUSE WIND SPEEDS TO
INCREASE ON OUR COASTAL WATERS TONIGHT. GUSTS NEAR 25 KNOTS ARE
POSSIBLE AT THAT TIME AND WE MAY NEED TO ISSUE ANOTHER SMALL CRAFT
ADVISORY TO COVER THAT PERIOD ONCE THE CURRENT ADVISORY ENDS,
ESPECIALLY IN OUR SOUTHERN WATERS WHERE THE PRESSURE GRADIENT WILL
BE STRONGEST.

OUTLOOK...
FRIDAY...WINDS WILL PICK UP IN THE NORTHWESTERLY FLOW AND WIND
GUSTS AROUND 25 TO 30 KNOTS WILL BE POSSIBLE OVER THE OCEAN
WATERS. A SMALL CRAFT ADVISORY MAY BE NEEDED.

SATURDAY...SUB-ADVISORY CONDITIONS EXPECTED.

SUNDAY THROUGH MONDAY...SEAS AND WINDS WILL NEAR SMALL CRAFT
ADVISORY LEVELS AS A COLD FRONT APPROACHES AND THEN CROSS THE
REGION ON MONDAY.

&&

.EQUIPMENT...
KDIX WSR-88D RADAR IS INOPERATIVE. TECHNICIANS HAVE BEEN NOTIFIED
AND WILL TROUBLESHOOT THE ISSUE. TPHL TDWR SHOULD PROVIDE
SUFFICIENT BACKUP RADAR COVERAGE FOR MONITORING THE SNOW SHOWERS
IN NORTHEASTERN PA AND CENTRAL/NORTHERN NJ.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM EST THIS
     AFTERNOON FOR ANZ450>455.

&&

$$
SYNOPSIS...MEOLA
NEAR TERM...KLEIN
SHORT TERM...IOVINO
LONG TERM...MEOLA
AVIATION...IOVINO/KLEIN/MEOLA
MARINE...IOVINO/KLEIN/MEOLA
EQUIPMENT...KLEIN






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