AFOS product AFDPHI
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Displaying AFOS PIL: AFDPHI
Product Timestamp: 2013-02-22 04:05 UTC

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FXUS61 KPHI 220405
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1105 PM EST THU FEB 21 2013

.SYNOPSIS...
NORTHWEST WINDS WILL DIMINISH AS HIGH PRESSURE SETTLES OVER THE
AREA EARLY FRIDAY. THE HIGH WILL THEN MOVE EAST. LOW PRESSURE
WILL MOVE INTO THE UPPER GREAT LAKES FRIDAY WHILE A SECOND LOW
FORMS OVER THE CAROLINAS. THIS SECOND LOW WILL MOVE NORTHEAST AND
AFFECT OUR WEATHER UNTIL SUNDAY MORNING. HIGH PRESSURE WILL BUILD
IN EARLY NEXT WEEK BEFORE ANOTHER SYSTEM APPROACHES NEXT TUESDAY.

&&

.NEAR TERM /THROUGH FRIDAY/...
OVERNIGHT...THE LOW TO OUR NORTHEAST WILL LOSE ITS EFFECT ON OUR
WEATHER OVERNIGHT AS A MID LEVEL RIDGE AND ASSOCIATED SURFACE
HIGH APPROACH THE AREA. A CLEAR SKY IS EXPECTED FOR THIS EVENING.
THE CONVECTIVELY PRODUCED HIGH CLOUDS THAT WERE OVER THE MIDDLE
MISSISSIPPI RIVER VALLEY AT MID AFTERNOON WILL BEGIN TO DRIFT OVER
OUR REGION LATE TONIGHT.

WIND SPEEDS WILL DIMINISH GRADUALLY. THE GUSTY NORTHWEST WIND
WILL LESSEN SLOWLY THROUGH THE REST OF THE EVENING AND THE WIND IS
EXPECTED TO BECOME NORTHERLY AT 8 MPH OR LESS OVERNIGHT. SOME
LOCATIONS WILL LIKELY GO TO A LIGHT AND VARIABLE WIND ALLOWING FOR
SOME RADIATIONAL COOLING. MINIMUM TEMPERATURES ARE ANTICIPATED TO
RANGE FROM ABOUT 15 TO 25 IN OUR REGION.

FRIDAY...A MID LEVEL RIDGE AXIS WILL PROGRESS TO THE EAST AND SHOULD
PASS OVERHEAD LATE ON FRIDAY.

FRIDAY WILL LIKELY FEATURE HIGH CLOUDS IN THE MORNING. MID LEVEL 
CLOUDS ARE FORECAST TO OVERSPREAD OUR REGION FROM THE SOUTHWEST 
DURING THE AFTERNOON HOURS. STRATOCUMULUS SHOULD BE ON THE INCREASE 
LATE IN THE DAY DUE TO THE ESTABLISHMENT OF AN ONSHORE FLOW IN THE 
LOW LEVELS OF THE ATMOSPHERE.

IT APPEARS AS THOUGH PRECIPITATION WILL BEGIN TO ARRIVE IN OUR 
REGION LATE IN THE DAY ON THE HEELS OF THE MID LEVEL RIDGE AXIS. THE 
LEADING EDGE OF THE PRECIPITATION SHOULD BE AROUND A READING TO 
PHILADELPHIA TO CAPE MAY LINE BY 700 PM FRIDAY. BOUNDARY LAYER 
TEMPERATURES SHOULD SUPPORT RAIN AT THE ONSET ON THE COASTAL PLAIN. 
AREAS TO THE NORTHWEST MAY SEE A MIX OF LIGHT RAIN, SLEET AND SNOW 
BASED ON THE FORECAST TEMPERATURE PROFILES.

&&

.SHORT TERM /FRIDAY NIGHT/...
SE PA W OF PHL...PERIODS LIGHT SNOW TO LIGHT ICE TO RAIN. POSSIBLE
WINTER WX ADVY.

LEHIGH VALLEY AND NW NJ N OF I78...LIGHT SNOW TO ICE EXCEPT N OF
I80 MOSTLY LIGHT SNOW WHICH INCLUDES POCONOS AND SUSSEX COUNTY.
PROBABLE WINTER WX ADVY.

REMAINDER...PERIODS OF LIGHT RAIN MAINLY LATE. 

TEMPS/WINDS: BLENDED 00Z/22 NCEP MOS MOS UNLESS OTHERWISE NOTED.
POPS: HAVENT FIGURED OUT YET.



&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
IT SHOULD BE RATHER ACTIVE DURING THE LONG TERM PART OF THE
FORECAST. 

SAT...WIDESPREAD RAINS ACROSS THE AREA WITH .5 TO 1.0 QPF
EXPECTED. THERE COULD STILL BE BIT OF SNOW FAR NORTH AT THE HIGHER
ELEVATIONS. THE LOW MOVES AWAY SAT NIGHT AND THE STEADY PRECIP
SHOULD END BY SUN MORNING...BUT GUSTY WINDS AND PARTLY TO MOSTLY
CLOUDY SKIES ARE EXPECTED. TEMPERATURES WILL BE AT OR ABOVE NORMAL
FOR THE WEEKEND.

HIGH PRESSURE WILL BUILD IN LATER SUNDAY AND REMAIN INTO MONDAY
NIGHT. THIS SHOULD BRING A PERIOD OF LESS EVENTFUL WEATHER TO THE
AREA. TEMPERATURES FOR THIS PERIOD WILL BE AROUND 5 DEGREES ABOVE
NORMAL FOR LATE FEBRUARY. 

ANOTHER LOW PRESSURE SYSTEM WILL APPROACH LATER TUESDAY AND
POSSIBLY LINGER INTO THURSDAY OR NEXT WEEK. THE 12Z DETERMINISTIC
MODELS ARE OFFERING VARYING SOLUTIONS WITH REGARDS TO HOW LONG THE
SYSTEM REMAINS OVER THE AREA. IT APPEARS TO BE MORE OF A WET (THAN
WHITE) SYSTEM AT THIS TIME. A TREND TOWARD LOWER TEMPERATURES
(BACK TO BELOW NORMAL) SHOULD BEGIN BY WED AND LAST PAST THURSDAY.
THERE MAY BE SOME LIGHT SNOW BEHIND THE SYSTEM NEXT THU.

&&

.AVIATION /04Z FRIDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, 
KMIV, KACY AND SURROUNDING AREAS.

OVERNIGHT...VFR CLEAR WITH CIRRUS INCREASING LATE. NNW WIND GUSTS
DIMINISHING TO LESS THAN 12 KTS AND BECOMING NNE BY MORNING.

AFTER 12Z FRIDAY...VFR DEVELOPING CIGS ABV 15000 IN THE MORNING
LOWERING TO 5000 FT LATE IN THE DAY. WIND NE BECOMING SE AND
GENERALLY UNDER 12 KTS. 

FRIDAY NIGHT...CONDITIONS LOWERING TO IFR LATE WITH SNOW TO
SLEET/FREEZING RAIN KABE/KRDG. CHANCE OF SNOW/RAIN MIXED AT THE
START KILG-KPHL/PNE/KTTN FRIDAY EVENING BUT BECOMING RAIN LATE.
ALL RAIN AND MOSTLY LATE AT KMIV AND KACY. WINDS E TRENDING NE
LATE AND UNDER 15 KTS. 

OUTLOOK...
SATURDAY THRU SUN MORNING...SUB VFR CONDITIONS WITH LOW CLOUDS
AND PCPN. GUSTY WINDS EXPECTED SUNDAY. SUN AFTERNOON THRU MON
NGT...MOSTLY VFR. INCREASING CLOUDS MON NGT. TUESDAY...SUB VFR
CONDITIONS WITH LOW CLOUDS/PCPN.

&&

.MARINE...
THE SMALL CRAFT ADVISORY REMAINS IS IN EFFECT UNTIL 1 AM FOR ALL
WATERS EXCEPT THE UPPER BAY, WHERE IT WAS DROPPED. SUB-ADVISORY
CONDITIONS WILL FOLLOW ELSEWHERE OVERNIGHT ON A MODERATE NORTH
WIND.

THE WIND IS FORECAST TO VEER TOWARD THE EAST AND SOUTHEAST FOR 
FRIDAY AS OUR NEXT WEATHER SYSTEM APPROACHES FROM THE WEST. WIND 
SPEEDS AND WAVE HEIGHTS ON FRIDAY SHOULD REMAIN WELL BELOW THE SMALL 
CRAFT ADVISORY CRITERIA.

OUTLOOK...
SMALL CRAFT CONDITIONS WILL DEVELOP ON THE WATERS SATURDAY AND
PERSIST INTO MONDAY. LOW END GALE WIND GUSTS ARE POSSIBLE SUNDAY. 
MORE SCA CONDITIONS AFTER TUE NEXT WEEK.

&&

.TIDES/COASTAL FLOODING...
BASED ON THE LATEST WATER LEVEL TRENDS AND ON THE DIMINISHING
WINDS, WATER LEVELS LIKELY WILL RECOVER ENOUGH BEFORE THE LATE
NIGHT LOW TIDE TO AVOID ADDITIONAL PROBLEMS WITH LOW WATER
LEVELS. WE WERE MONITORING REEDY POINT, WHICH IS THE LOCATION MOST
LIKELY TO CONFOUND US. AS OF 930 PM EST, IT LOOKED UNLIKELY THAT
REEDY POINT WOULD HIT THE LOW WATER ADVISORY LEVEL OF MINUS 1.8
FEET MEAN LOWER LOW WATER. THE NEXT LOW TIDE THERE IS AT 233 AM.
WE WILL CONTINUE TO MONITOR.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 1 AM EST FRIDAY FOR ANZ431-450>455.

&&

$$
SYNOPSIS...O'HARA
NEAR TERM...DRAG/IOVINO 1105
SHORT TERM...DRAG/IOVINO 1105
LONG TERM...O'HARA
AVIATION...DRAG/IOVINO/O'HARA 1105
MARINE...DRAG/IOVINO/O'HARA 1105
TIDES/COASTAL FLOODING...