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000
FXUS61 KPHI 231939
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
339 PM EDT WED APR 23 2014

.SYNOPSIS...
A HIGH PRESSURE SYSTEM LOCATED OVER THE GREAT LAKES REGION THIS
AFTERNOON WILL BUILD SOUTH AND EAST THEN ACROSS OUR REGION
THROUGH FRIDAY AND THEN WEAKEN FRIDAY NIGHT. A LOW PRESSURE SYSTEM
WILL MOVE NORTH OF THE AREA FRIDAY NIGHT AND SATURDAY. ITS
ASSOCIATED FRONT WILL CROSS THE REGION EARLY SATURDAY. MORE HIGH
PRESSURE WILL ARRIVE FOR SUNDAY AND SUNDAY NIGHT. AN UNSETTLED
PATTERN WILL SET UP FOR NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
LAST NIGHT`S COLD FRONT IS WELL OFFSHORE. SURFACE HIGH PRESSURE,
CENTERED OVER THE WESTERN GREAT LAKES, IS TRYING TO PUSH EAST. THE
MID-LEVEL TROUGH AXIS HAS PIVOTED OFF THE COAST AND HAS TAKEN THE
ISOLATED/SCATTERED SHOWERS, WHICH WERE TO TOUR NORTH, WITH IT.

WHILE THE SURFACE HIGH PUSHES EAST OVERNIGHT, WE`LL STILL HAVE SOME
GRADIENT TO DEAL WITH ALONG WITH SOME COLD AIR ADVECTION.

IT WILL BE A COLD NIGHT WITH MINIMUM WINDS CHILLS IN THE TEENS AND
20S. ACTUAL AIR TEMPERATURES WILL BE IN THE MID 20S ON THE LOW END
TO UPPER 30S ON THE HIGH END. SKIES WILL BE CLEAR.

MOST OF THE DEFINED SPRING GROWING AREA, FOR THE THIRD WEEK OF
APRIL, WILL BE IN THE MID TO UPPER 30S OVERNIGHT. WE WILL NOT BE
ISSUING A FREEZE WARNING. THERE IS PATCHY FROST IN THE GRIDS, BUT WE
ALSO FEEL THE WIND WILL PRECLUDE ANY WIDESPREAD FROST. A FROST
ADVISORY WILL NOT BE ISSUED EITHER AT THIS TIME.

&&

.SHORT TERM /THURSDAY/...
WITH THE SURFACE HIGH BUILDING ACROSS THE REGION TOMORROW AND THE
COLD AIR ADVECTION SHUTTING OFF, TEMPERATURES WILL REBOUND NICELY.
HIGHS WILL BE IN THE 50S ACROSS THE NORTH AND WEST, AND IN THE LOWER
TO MID 60 ELSEWHERE. STILL, A FEW DEGREES BELOW NORMAL.

SKIES WILL BE MAINLY CLEAR.

NORTHWEST WINDS WILL BE IN THE 15 TO 25 MPH RANGE.

&&

.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
HIGH PRESSURE BUILDS INTO THE REGION THURSDAY NIGHT AND EARLY
FRIDAY IN ADVANCE OF AN APPROACHING STORM SYSTEM AND ASSOCIATED
FRONT.

THE LOW PRESSURE SYSTEM PASSES BY TO OUR NORTH. AND THE ASSOCIATED FRONT
SWINGS THROUGH THE REGION FRIDAY NIGHT INTO EARLY SATURDAY.
INSTABILITY LOOKS LIMITED ENOUGH TO KEEP MENTION OF THUNDER OUT OF
THE FORECAST...CONSISTENT WITH THE PREVIOUS FORECAST. LAST TWO GFS
RUNS SUGGEST SOME PRECIPITATION MOVING THROUGH THE REGION AS UPPER
TROUGH ROTATES THROUGH DURING THE DAY SATURDAY SO EXTENDED CHANCE
POPS FURTHER SOUTH ACROSS THE AREA. NO OTHER CHANGES OF
SIGNIFICANCE TO THE PREVIOUS FORECAST.

MET/MAV BLEND WAS USED FOR TEMPERATURES IN THURSDAY NIGHT INTO
FRIDAY NIGHT TIME FRAME.

FAIR WEATHER MOVES BACK INTO THE REGION, FOR SATURDAY NIGHT AND
CONTINUES INTO EARLY MONDAY.

MODELS CONTINUE TO ADVERTISE PATTERN CHANGE WITH INCREASED
BLOCKING, SLOWING STORMS SYSTEMS DOWN. REMAINDER OF EXTENDED
FORECAST PERIOD WILL BE IMPACTED BY APPROACH OF SLOW MOVING STORM
SYSTEM TO OUR WEST. SLOW SPEED AND SIGNIFICANT TAPPING OF GULF AND
ATLANTIC MOISTURE SUGGEST THIS WILL BE A VERY WET STORM SYSTEM FOR
SOME LOCATIONS. AND THAT COULD WIND UP INCLUDING US.

WPC TEMPS/POPS WERE USED AS PRIMARY INPUT FOR THE GRIDS IN THE
SATURDAY THROUGH WEDNESDAY TIME FRAME.

I VERY SELDOM PUT POPS HIGHER THAN 50% OUT IN DAY 7. BUT GIVEN
CONSISTENT MODEL SIGNAL OVER PAST SEVERAL DAYS AS WELL AS WPC
GUIDANCE, TODAY I DID.

&&

.AVIATION /19Z WEDNESDAY THROUGH MONDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.

VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. WE`LL HAVE STRATOCU
INTO THE EVENING HOURS, THEN GO CLEAR. SKIES SHOULD REMAIN MAINLY
CLEAR TOMORROW.

THE ONLY ISSUE FOR TONIGHT AND TOMORROW WILL EB THE WIND. NORTHWEST
WINDS WILL SLACKEN A BIT FROM THIS AFTERNOON`S LEVELS, BUT STILL
GUST TO 25 KT.

OUTLOOK...
THU NIGHT THROUGH FRI MORNING...VFR EXPECTED.
FRI AFTERNOON THROUGH SAT...MOSTLY VFR WITH SCT SHOWERS POSSIBLE.
SAT NGT THRU MON...MOSTLY VFR.

&&

.MARINE...
PER OBSERVATIONS AND FORECASTS SOUNDINGS, A GALE WARNING REMAINS IN
PLACE FOR THE DELAWARE BAY THROUGH MIDNIGHT. THE GALE WARNING WILL
REMAIN IN PLACE FOR THE OCEAN THROUGH MIDDAY TOMORROW. ADDITIONAL
SMALL CRAFT ADVISORY HEADLINES WILL BE NEEDED THEREAFTER, POSSIBLY
INTO TOMORROW EVENING.

OUTLOOK...
THU NIGHT THRU MON...MOSTLY SUB-SCA CONDITIONS. NEAR SCA GUSTS
FRI AFTERNOON/EVENING.

&&

.FIRE WEATHER...
A RED FLAG WARNING REMAINS IN EFFECT THROUGH 8 PM TONIGHT. A FIRE
WEATHER WATCH IS IN PLACE FOR THURSDAY.

WHILE RH`S WILL PROBABLY BOTTOM OUT IN THE 30-40% RANGE THE NEXT
HOUR OR SO, WINDS AND FINE FUEL MOISTURE ARE WELL WITHIN NEEDED
CRITERIA.

THE MAIN CONCERN IS THE WIND WHICH WILL GUST IN THE 30 TO 35 MPH
RANGE. ANY FIRE THAT GETS STARTED WILL SPREAD QUICKLY UNDER THESE
CONDITIONS.

MORE FIRE WEATHER CONCERNS FOR TOMORROW. WIND GUSTS WILL BE A BIT
LOWER. HOWEVER, WITH WARMER TEMPS...RH VALUES WILL DROP BELOW 20 PCT
IN MANY LOCATIONS THURSDAY AFTERNOON. THE FUEL MOISTURE LEVELS WILL
CONTINUE TO BE RATHER LOW. ALL THREE CRITERIA (WIND, FUELS, RH`S)
SHOULD BE MET WITH THE EXCEPTION OF MAYBE THE LOWER DELMARVA.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...RED FLAG WARNING UNTIL 8 PM EDT THIS EVENING FOR PAZ054-055-
     060>062-070-071-101>106.
     FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY
     EVENING FOR PAZ054-055-060>062-070-071-101>106.
NJ...RED FLAG WARNING UNTIL 8 PM EDT THIS EVENING FOR NJZ001-
     007>010-012>027.
     FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY
     EVENING FOR NJZ001-007>010-012>027.
DE...RED FLAG WARNING UNTIL 8 PM EDT THIS EVENING FOR DEZ001>004.
     FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY
     EVENING FOR DEZ001>004.
MD...RED FLAG WARNING UNTIL 8 PM EDT THIS EVENING FOR MDZ008-012-
     015-019-020.
     FIRE WEATHER WATCH FROM THURSDAY MORNING THROUGH THURSDAY
     EVENING FOR MDZ008-012-015-019-020.
MARINE...GALE WARNING UNTIL NOON EDT THURSDAY FOR ANZ450>455.
     SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO NOON EDT
     THURSDAY FOR ANZ430-431.
     GALE WARNING UNTIL MIDNIGHT EDT TONIGHT FOR ANZ430-431.

&&

$$
SYNOPSIS...SZATKOWSKI
NEAR TERM...KRUZDLO
SHORT TERM...KRUZDLO
LONG TERM...SZATKOWSKI
AVIATION...SZATKOWSKI/KRUZDLO
MARINE...SZATKOWSKI/KRUZDLO
FIRE WEATHER...KRUZDLO