Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000
FXUS61 KPHI 220012
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
812 PM EDT THU AUG 21 2014

.SYNOPSIS...
WEAK LOW PRESSURE WILL CROSS THE REGION TONIGHT THROUGH FRIDAY
NIGHT AND THEN MOVE OFF THE COAST SATURDAY. HIGH PRESSURE WILL
BUILD ACROSS THE AREA THIS WEEKEND AND REMAIN IN CONTROL OF THE
WEATHER INTO NEXT WEEK. A COLD FRONT WILL APPROACH THE AREA NEXT
WEDNESDAY.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
STABLE AIR WAS CONTINUING TO ADVECT OFF THE OCEAN THIS EVENING.
DEW POINT READINGS WERE DROPPING INTO THE UPPER 50S AND LOWER 60S
IN MUCH OF NEW JERSEY. MEANWHILE, CONDITIONS REMAINED UNSTABLE ON
THE WESTERN SIDE OF OUR FORECAST AREA.

CONDITIONS ARE FORECAST TO BECOME INCREASINGLY STABLE DURING THE
EVENING WITH THE LOSS OF DAYTIME HEATING AND THE CONTINUED ONSHORE
FLOW.

WE WILL KEEP THE MENTION OF THUNDERSTORMS WITH HEAVY RAINFALL
ACROSS OUR FAR NORTHERN COUNTIES FOR THIS EVENING TO ACCOUNT FOR
THE CONVECTION MOVING ACROSS NORTHEASTERN PENNSYLVANIA AND INTO
NORTHERN NEW JERSEY.

WE HAVE ADJUSTED THE EVENING THUNDERSTORM FORECAST BASED ON THE
RADAR TRENDS TO INCLUDE AREAS FROM BERKS COUNTY AND UPPER
MONTGOMERY COUNTY DOWN TO THE UPPER EASTERN SHORE OF CHESAPEAKE
BAY.

A MID LEVEL SHORT WAVE THAT WAS LOCATED OVER THE EASTERN GREAT
LAKES REGION EARLY THIS EVENING SHOULD CONTINUE TO PROGRESS
SOUTHEASTWARD AND IT IS ANTICIPATED TO PASS OVERHEAD LATE TONIGHT.
AS A RESULT, WE WILL MAINTAIN SCATTERED SHOWERS THROUGHOUT OUR
FORECAST AREA FOR TONIGHT, EVEN AFTER THE THUNDERSTORMS WEAKEN.

TEMPERATURES ARE EXPECTED TO DROP INTO THE 60S OVERNIGHT WITH A
LIGHT SOUTH TO EAST WIND.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH 6 PM FRIDAY/...
1000J OF MLCAPE AND SLIGHTLY STRONGER 0-6KM BULK SHEAR CUES
INTEREST IN CONVECTION FRI AFTN. SREF HAS DECENT PROBS FOR
SHOWERS...ESPECIALLY E PA...S NJ AND THE DELMARVA. FOR NOW HAVE
PLAYED THE SHOWER AND TSTM RISK CONSERVATIVELY AND MAINTAINED THE
330 AM THURSDAY FCST POPS FOR FRIDAY...ABOUT 10 PCT BELOW THE
12Z/21 GFS/NAM MOS BLEND.

IT WILL BE SLIGHTLY COOLER AS THE FLOW TURNS MORE EASTERLY AS THE
SFC LOW CONSOLIDATES TO THE S OF THE DELMARVA.

FCST BASIS: TEMPS/DEWS/WINDS ARE A 50 50 BLEND OF THE 12Z/21
GFS/NAM MOS.

&&

.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
THE AREA WILL CONTINUE TO BE UNDER THE INFLUENCE OF THE WEAK
UPPER LOW AND SFC LOW THU NIGHT AND INTO FRIDAY. SCT SHOWERS AND A
FEW TSTMS WILL BE ACROSS MOST AREAS THU EVENING AND THEN DIMINISH
OVERNIGHT...A COUPLE LEFTOVER SHOWERS WILL DEVELOP SAT MOSTLY
ACROSS THE DELMARVA...SE PA AND SRN NJ. CHC FOR SHOWERS ARE ONLY
IN THE CHC RANGE HOWEVER. A FEW DOWNPOURS ARE STILL POSSIBLE THU
NIGHT WITH THE HIGHER PWATS STILL ACROSS THE SRN AREAS. LOWS THU
NIGHT WILL MOSTLY BE IN THE LOW 60S ACROSS THE NORTH AND MID/UPPER
60S ELSEWHERE. HIGHS SAT IN THE UPPER 70S/LOW 80S SOUTH AND LOW TO
MID 70S NORTH. DRIER AIR WILL CONTINUE TO PUSH IN FROM NORTH TO
SOUTH SAT.

AN UPPER RIDGE BUILDS UP TO THE WEST OF THE AREA THIS WEEKEND AND
THEN ROTATES ACROSS THE AREA EARLY NEXT WEEK. SFC HIGH PRESSURE
WILL MOVE SLOWLY IN TANDEM WITH THE UPPER HIGH. THIS WILL PRODUCE
A PERIOD OF DRY WEATHER FOR OUR REGION. POPS FOR SAT NIGHT THRU
NEXT WEN NIGHT ARE SUB-15PCT RANGE FOR THE ENTIRE AREA.
TEMPERATURES WILL BE A FEW DEGREES BELOW NORMAL SUN/MON...NEAR
NORMAL TUE...AND THEN A BIT ABOVE NORMAL WED/THU. HUMIDITY LEVELS
WILL BE COMFORTABLE THROUGH MUCH OF THE PERIOD...BUT WILL TREND UP
TOWARD THE MIDDLE OF NEXT WEEK.

&&

.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

SCATTERED SHOWERS ARE ANTICIPATED FOR TONIGHT. ISOLATED
THUNDERSTORMS ARE EXPECTED FOR THIS EVENING TO THE NORTH OF KABE
AND KTTN AND TO THE WEST AND SOUTHWEST OF KPHL AND KILG, INCLUDING
THE KRDG AREA. CONDITIONS SHOULD BE GENERALLY VFR THROUGH 0600Z
EXCEPT THEY MAY LOWER TO MVFR IN RAIN SHOWERS.

MVFR CONDITIONS ARE EXPECTED TO PREVAIL FROM LATE TONIGHT INTO
FRIDAY MORNING. SOME SPOTS COULD FALL TO IFR DEPENDING UPON THE
EXTENT OF ANY STRATUS AND FOG DEVELOPMENT ALONG WITH ADDITIONAL
SHOWER ACTIVITY. MAINLY VFR CONDITIONS ARE EXPECTED TO RETURN FOR
FRIDAY AFTERNOON AND THERE IS A CHANCE OF SHOWERS AND
THUNDERSTORMS AT THAT TIME.

THE WIND SHOULD BACK FROM THE SOUTH AND SOUTHEAST TO THE EAST
DURING THE TAF PERIOD. SPEEDS ARE EXPECTED TO BE MAINLY LESS THAN
10 KNOTS

OUTLOOK...
FRI NIGHT THRU SAT...MOSTLY VFR BUT SCT SHOWERS MAY BRING LOWER
CONDITIONS.

SAT NIGHT THRU TUESDAY...VFR EXPECTED.

&&

.MARINE...
SUB-SMALL CRAFT ADVISORY CONDITIONS EXPECTED THROUGH FRIDAY WITH
SEAS 3 FEET OR LESS AND SOUTH TO SOUTHEAST WINDS 5 TO 10 KNOTS
BECOMING EASTERLY FRIDAY.

WE`VE NOT SEEN ANY NEW MAREPS THIS WEEK FROM MARINERS IN OUR EASY
USE (INTERNET AND/OR SMART PHONE) LINK
WWW.WEATHER.GOV/PHI/MAROBSFORM THIS HAS BEEN DERIVED FOR THE
MARINER TO EASILY POST INFO INSTANTLY TO THE NWS FOR USE IN OUR
MARINE PRODUCTS.

OUTLOOK...
THU NIGHT THRU FRI NIGHT...SUB SCA CONDITIONS WITH SCT SHOWERS.

SAT AND SAT NIGHT...LOW END SCA CONDITIONS EXPECTED ON THE OCEAN.
FAIR WEATHER.

SUN THRU TUE...SUB-SCA CONDITIONS WITH FAIR WEATHER.

&&

.CLIMATE...
WE RCD INQUIRY ON HOW THE CLIMATE PROGRAM SELECTS FOR OUR 530 PM
CLI. OUR PROGRAM SEARCHES MAX/MIN TEMP DATA FOR THE DAY ENDING 5PM
SHARP. THAT DATA IS INGESTED INTO THE 530 PM POSTED CLI. IF A MAX
TEMP OCCURS THEREAFTER...IT IS REFLECTED IN THE END OF DAY SUMMARY
POSTS AROUND 230 AM EDT THE NEXT DAY AND ALSO YOU CAN CHECK THE 8
PM RTPPHI WHICH POSTS AROUND 815 PM EDT.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...NONE.

&&

$$

SYNOPSIS...O`HARA
NEAR TERM...IOVINO
SHORT TERM...DRAG
LONG TERM...O`HARA
AVIATION...IOVINO/O`HARA
MARINE...DRAG/O`HARA
CLIMATE...DRAG





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