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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KPHI 061729
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1229 PM EST THU MAR 6 2014

.SYNOPSIS...
STRONG CANADIAN HIGH PRESSURE WILL BUILD ACROSS THE NORTHEAST STATES
TODAY, BEFORE SHIFTING EAST AND OFF THE NEW ENGLAND COAST FRIDAY.
ELSEWHERE, LOW PRESSURE IS FORECAST TO DEVELOP NEAR THE SOUTHEAST
UNITED STATES COASTLINE THURSDAY NIGHT AND THEN TRACK NORTHEAST AND
AWAY FROM THE COAST FRIDAY NIGHT. OVER THE WEEKEND, A COLD FRONT
WILL PASS THROUGH THE REGION LATE SATURDAY. WEAK HIGH PRESSURE WILL
THEN DEVELOP TO OUR SOUTH INTO EARLY NEXT WEEK, WITH A FEW WEAK
DISTURBANCES MOVING ACROSS THE GREAT LAKES TO NORTHEAST STATES.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
NO BIG CHANGES WITH THIS UPDATE. OTHER IN OUR DELMARVA AREA, THE
STRATOCU IS HAVING A HARDER TIME GETTING INLAND. THE LATEST WRF-
NMMB DOES SHOW SOME DRYING OF THE 925MB MOISTURE THIS AFTERNOON IN
OUR CWA. THE CIRRUS IS THINNING, SO A SUNNIER AFTERNOON,
ESPECIALLY NORTH AND WE LOWERED SKY COVER. TEMPS AND DEWPTS ARE
ON/CLOSE TO SCHEDULE.

A LARGE AREA OF HIGH PRESSURE WILL BE LOCATED TO OUR N ERLY TODAY
AND IT WILL GRADUALLY MOVE TO THE NE AS A WK LOW PASSES WELL
OFFSHORE.  THIS WILL KEEP NELY FLOW OVER THE REGION TODAY.

OFTENTIMES IN ERLY SPRING, IT ALL COMES DOWN TO HOW MUCH SUN WE SEE
AND THE DIRECTION OF THE WIND AS TO WHAT OUR TEMPS WILL BE.  WE SAW
THIS FACT DEMONSTRATED ON WED WHEN WITH FULL SUNSHINE AND LIGHT WIND
(DESPITE BEING FROM THE N) TEMPS WERE HIGHER THAN FCST AND IT ENDED
UP BEING A PLEASANT DAY.

WITH YESTERDAY`S WK CFP AND THE MORE NELY FLOW BRINGING IN COLD AIR
FROM THE ATLC AND MORE SOME MORE CLOUDS, TEMPS WILL BE BELOW NRML
TODAY.  THE LTST GUID INDICATES MANY LOCATIONS WON`T HIT FREEZING.
HOWEVER, IF WE SEE MORE SUNSHINE THAN ANTICIPATED WILL TEMPS BE A
BIT HIGHER (ALBEIT STILL BLO NRML?) OTHERWISE, IT WILL BE DRY.
TEMPS WILL GENLY BE IN THE 20S AND 30S.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM FRIDAY/...
THE AFOREMENTIONED HIGH MOVES FURTHER EWD TONIGHT, BUT STILL RIDGES
SWWD OVER THE MID-ATLC.  AS IT DOES, AN AREA OF LOW PRESSURE WILL
DEVELOP OVER THE GLFMEX, CROSS THE FL PENINSULA AND MOVE TO THE SERN
CST BY THE END OF THE PD.  THIS LOW WILL HAVE SOME IMPACT AFTER THE
SHORT TERM PD.  TONIGHT WILL BE DRY AS WELL, WITH INCREASING
CLOUDINESS ESPECIALLY OVER THE S AND E AS THE LOW APPROACHES.
OVERNIGHT LOWS WILL BE IN THE TEENS AND 20S.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
MODERATING TEMPERATURES WITH NEAR TO EVEN SLIGHTLY ABOVE AVERAGE
READINGS CONTINUE TO BE IN THE PICTURE THROUGH THE LONG TERM PERIOD.
TO START OFF, AN AREA OF STRONG CANADIAN HIGH PRESSURE WILL BE
PROGRESSING EAST AND OFF THE NEW ENGLAND COAST FRIDAY AS AN AREA OF
LOW PRESSURE ALONG THE SOUTHEASTERN SEABOARD SLOWLY TRACKS NORTHEAST
ALONG THE CAROLINA COAST. A NOTICEABLE TREND IN MODEL GUIDANCE, FROM
THE GFS TO ECMWF AND OTHERS, IS A SLIGHTLY MORE WESTWARD TRACK OF
THIS SYSTEM, KEEPING IT CLOSER TO COAST BEFORE TAKING IT NORTHEAST
AND OUT TO SEA LATER FRIDAY NIGHT. WHAT THIS MEANS FOR OUR REGION IS
AN INCREASING CHANCE FOR SOME PRECIP ACROSS OUR SOUTHERN ZONES,
MAINLY OUR SOUTHERN DELMARVA AND FAR SOUTHERN NJ. LOW CHANCE POPS
FRIDAY MORNING INCREASE TO LIKELY POPS INTO FRIDAY AFTERNOON/EVENING
FOR THESE AREAS, WITH THE MOST LIKELY PRECIP TYPE BEING RAIN, EXCEPT
FOR SOME POSSIBLE SLEET AT THE ONSET IN SOME SPOTS IN THE MORNING.
FROM THERE, POPS DECREASE GOING THROUGH FRIDAY NIGHT AS THIS LOW
PRESSURE TRACKS NORTHEAST AND AWAY FROM THE COAST.

INTO SATURDAY, A WEAK AREA OF LOW PRESSURE WILL BE TRAVERSING ACROSS
SOUTHEASTERN CANADA AND FAR NORTHERN NEW ENGLAND, WITH ITS
ASSOCIATED COLD FRONT APPROACHING OUR REGION FROM THE WEST. MAINLY
QUIET CONDITIONS ARE EXPECTED THROUGH THE DAYTIME SATURDAY AHEAD OF
THIS FRONTAL BOUNDARY. THIS COLD FRONT IS EXPECTED TO CROSS THE AREA
LATER SATURDAY NIGHT, WITH A SHORTWAVE/VORT MAX ALSO PASSING OVER
THE REGION INTO EARLY SUNDAY. ONLY LIMITED MOISTURE IS ASSOCIATED
WITH THESE FEATURES, BUT WE HAVE KEPT SOME LOW POPS IN PLACE FOR
POSSIBLE SNOW/RAIN SHOWERS NORTH SATURDAY NIGHT AND POSSIBLE RAIN
SHOWERS SOUTH INTO SUNDAY.

THROUGH THE LATTER HALF OF SUNDAY AND INTO EARLY NEXT WEEK, WEAK
HIGH PRESSURE IS EXPECTED TO DEVELOP TO OUR SOUTH AS A FEW, MAINLY
WEAK DISTURBANCES PASS BY TO OUR NORTH ACROSS THE GREAT LAKES AND
INTO THE NORTHEAST STATES. OVERALL, WE HAVE KEPT A DRY FCST SUNDAY
NIGHT THROUGH MONDAY AND INTRODUCE SOME LOW POPS ACROSS THE AREA
LATER TUESDAY AS SURFACE RIDGING MOVES FARTHER SOUTHWARD. THE MODELS
THEN TEND TO REALLY DIVERGE GOING INTO WEDNESDAY AS THE ECMWF
PRESENTS AN ORGANIZING LOW PRESSURE SYSTEM TO AFFECT THE REGION,
WHILE THE GFS HOLDS OFF BRINGING ANY NOTABLE SYSTEM/PRECIP TO THE
AREA UNTIL LATER NEXT WEEK AS STRONG HIGH PRESSURE REMAINS IN PLACE
TO OUR NORTH. WITH THESE MIXED MODEL SOLUTIONS FOR THE MIDDLE OF
NEXT WEEK, ONLY MINOR CHANGES WERE MADE TO THE WEDNESDAY TIMEFRAME.

&&

.AVIATION /17Z THURSDAY THROUGH MONDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

THE 18Z TAFS IS A STAIR STEP DOWNWARD INTO MVFR CONDITIONS AND
POSSIBLY IFR SOUTHEASTERN AIRPORTS/TERMINALS ON FRIDAY MORNING.

FOR THIS AFTERNOON WE ARE FORECASTING VFR CONDITIONS EXCEPT AT
KMIV AND KACY WHERE SOME MVFR CIGS ARE POSSIBLE. LOWER CLOUDS
CONTINUE TO LURK JUST EAST. EAST TO NORTHEAST WINDS WILL AVERAGE
AROUND 10 KNOTS.

THIS EVENING, WE ARE EXPECTING A BORDERLINE MVFR/VFR CIG TO
OVERSPREAD THE REMAINING TERMINALS AND CONTINUING AT SERN
TERMINALS AND AIRPORTS. WINDS WILL REMAIN EAST TO NORTHEAST AT 5
TO 10 KNOTS, STRONGER WINDS SOUTHEAST, SLIGHTLY WEAKER NORTHWEST
TERMINALS AND AIRPORTS.

OVERNIGHT GREATER CONFIDENCE OF MVFR CIGS PREVAILING. NO VSBY
RESTRICTIONS EXPECTED AND SIMILAR WIND SPEEDS AND DIRECTIONS.

ON FRIDAY MORNING, A LOWER MVFR CIGS IS FORECAST. THERE IS A
CHANCE IT MIGHT LOWER TO IFR. HIGHEST CHANCES ARE IN NJ AND DE
AIRPORTS. NORTHEAST WINDS SHOULD INCREASE TO ABOUT 10 TO 15
KNOTS ON AVERAGE, WITH POSSIBLE HIGHER GUSTS AT EASTERN AIRPORTS
AND KACY AND KMIV. SOME RAIN MIGHT MOVE INTO KACY AND KMIV BY THE
END OF THE CURRENT TAF PERIOD.

WE ARE NOT CONFIDENT ENOUGH OF THE RAIN BACKING INTO KPHL BEYOND
17Z. SO KEPT THE TERMINAL DRY FOR FRIDAY AFTERNOON. WE WILL MAINTAIN
THE LOW MVFR CIGS.

OUTLOOK...
FRIDAY NIGHT...POSSIBLE MVFR CONDITIONS, MAINLY KMIV/KACY AND
SOUTH SOME LIGHT RAIN.

SATURDAY...VFR CONDITIONS.

SATURDAY NIGHT THROUGH SUNDAY...MAINLY VFR. POSSIBLE SUB-VFR IN ANY
PASSING AREAS LIGHT RAIN/SNOW SHWRS.

MONDAY... VFR CONDITIONS.

&&

.MARINE...
HIGH PRESSURE TO THE N WILL MOVE EWD TODAY INTO TONIGHT.   LOW
PRESSURE OVER THE GLFMEX WILL MOVE TED THE SERN CST TONIGHT.  AS A
RESULT A NELY FLOW WILL PREVAIL OVER THE REGION.  THE NELY FLOW WILL
KEEP INCREASED SEAS OVER THE AREA AND THE WIND SHOULD GUST INTO SCA
RANGE.  THEREFORE, THE PREVIOUSLY ISSUED SCA WILL REMAIN IN EFFECT.

OUTLOOK...
FRIDAY THROUGH SATURDAY...SMALL CRAFT ADVISORY CONDITIONS ARE
EXPECTED ON THE AREA WATERS. A STORM SYSTEM NEAR THE CAROLINA COAST
AND MOVING OUT TO SEA LATE FRIDAY NIGHT WILL LEAD TO SOME SCA WIND
GUSTS ACROSS OUR WATERS BETWEEN 25 TO 30 KNOTS (STRONGEST FOR THE
SOUTHERN WATERS)AND SEAS BETWEEN 5 TO 8 FEET FOR OUR COASTAL WATERS.
WIND GUSTS WILL GRADUALLY DECREASE INTO SATURDAY, BUT ELEVATED SEAS
WILL CONTINUE.

SUNDAY AND MONDAY...WINDS AND SEAS ARE EXPECTED TO BE BELOW SCA
LEVELS.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST SATURDAY FOR ANZ431-
     450>455.

&&

$$
SYNOPSIS...KLINE
NEAR TERM...GIGI/NIERENBERG
SHORT TERM...NIERENBERG
LONG TERM...KLINE
AVIATION...GIGI/KLINE
MARINE...KLINE/NIERENBERG