-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KPHI 292327
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
727 PM EDT THU JUL 29 2010

.SYNOPSIS...
A COLD FRONT WILL MOVE THROUGH THE REGION AND MOVE OFFSHORE
TONIGHT. HIGH PRESSURE WILL MOVE IN FROM THE WEST AND SETTLE OFF
THE NEW ENGLAND COAST. AN UPPER LEVEL DISTURBANCE MAY MOVE
THROUGH ON FRIDAY. A COLD FRONT MAY APPROACH THE AREA AROUND
MIDWEEK.

&&

.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
-- Changed Discussion --
LATEST RADAR IMAGERY SHOWS SOME SCATTERED SHOWERS OVER MAINLY CSTL
NJ, CSTL DE AND ALG THE ERN SHORE OF MD. A FEW THUNDERSTORMS CAN
NOT BE RULED OUT OVER THE NEXT COUPLE OF HOURS, BUT THE OVERALL
SEVERE THREAT HAS DECREASED. THEREFORE, THE SEVERE THUNDERSTORM
WATCH WAS CANCELLED EARLIER.

BEHIND THE FRONT WILL BE COOLER AND DRIER AIR, MAKING FOR QUITE A
COMFORTABLE NIGHT ACROSS THE REGION. ANY LINGERING SHOWER/TSTM
ACTIVITY SHOULD BE OVER WITH BY 9 PM IF NOT SOONER.

LOWS WILL RANGE FROM THE MID 50S TO MID 60S, WITH SOME COOLER
TEMPERATURES IN THE POCONOS. THE DELMARVA MAY SEE TEMPERATURES
CLOSER TO THE MID TO UPPER 60S OVERNIGHT.
-- End Changed Discussion --

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY/...
RELIEF FOR A FEW DAYS WILL USHER US INTO THE WEEKEND AS HIGH
PRESSURE BUILDS INTO THE AREA FROM THE WEST. THE HIGH WILL CONTROL
OUR WEATHER THROUGH THE PERIOD. THE MODELS INDICATE THAT AN UPPER
LEVEL DISTURBANCE MAY MOVE THROUGH ON FRIDAY, HOWEVER, WITH THE
DRIER CONDITIONS THERE MIGHT NOT BE MUCH MORE THAN SOME SPRINKLES
AROUND OUR NORTHERN AREAS. WE HAVE OPTED TO KEEP THE FORECAST DRY
THROUGH MOST OF THE PERIOD. A WEAK SURFACE LOW IS FORECAST TO MOVE
THROUGH ON SUNDAY. WE HAVE INCLUDED SOME SLIGHT CHANCE/CHANCE POPS
FOR SUNDAY.

HIGHS IN THE 80S AND LOWS IN THE 60S LOOK TO BE PREVALENT THROUGH
THE PERIOD.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
THE OVERALL UPPER-LEVEL PATTERN COMPRISES OF TROUGHING FROM THE
MIDWEST TO THE NORTHEAST AS ENERGY FROM THE PACIFIC NORTHWEST EJECTS
EASTWARD ALONG THE NORTHERN TIER STATES. A FAIRLY PRONOUNCED TROUGH
IS FORECAST TO BE ACROSS THE NORTHEAST AND MID ATLANTIC REGIONS
SUNDAY NIGHT WITH EVEN HINTS OF THIS MAINTAINING ITS PRESENCE
MONDAY. THE PATTERN ALMOST LOOKS TO BECOME AN OVERRUNNING/UPSLOPE
REGIME AS HIGH PRESSURE TRIES TO BUILD SOUTHWESTWARD FROM NEW
ENGLAND AS THE UPPER-LEVEL TROUGH BEGINS TO LIFT OUT. THERE ARE
QUESTIONS REGARDING THE TIMING OF THIS SYSTEM COMPLETELY LIFTING
OUT, WHICH WILL IMPACT THE SENSIBLE WEATHER. ONCE THIS FEATURE LIFTS
OUT, WEAK RIDGING IS FORECAST TO SPREAD ACROSS THE MID ATLANTIC
REGION. HOWEVER GIVEN THE PROGRESSIVE PATTERN, THE NEXT COLD FRONT
IS SCHEDULED TO ARRIVE WEDNESDAY INTO THURSDAY. THERE IS A FAIRLY
SUBSTANTIAL MID/UPPER LEVEL RIDGE FORECAST TO BE ACROSS THE SOUTHERN
STATES, THEREFORE THE COLD FRONT MAY GET HUNG UP IN OUR VICINITY
THURSDAY. HPC WENT WITH A COMPROMISE OF THE GFS AND ECMWF, ALTHOUGH
MADE SOME ADJUSTMENTS IN THE MID ATLANTIC REGION WITH A SMALL
PERCENTAGE OF THE MULTI-CLUSTER ENSEMBLE MEMBERS. THIS TAKES INTO
ACCOUNT THE SYSTEM THAT SLIDES ACROSS THE REGION AT THE BEGINNING OF
THIS TIME FRAME.

BASED ON THE ABOVE, A WEAK SURFACE LOW IS FORECAST TO BE SLIDING
ACROSS THE DELMARVA AREA LATE SUNDAY THEN EXITING TO OUR EAST SUNDAY
NIGHT AND MONDAY AS THE UPPER-LEVEL TROUGH MOVES OVERHEAD. AN AREA
OF HIGH PRESSURE BUILDS DOWN INTO THE AREA FROM NEW ENGLAND TUESDAY,
THEN A WARM FRONT TAKES AIM ON OUR CWA TUESDAY NIGHT INTO WEDNESDAY.
A COLD FRONT AND PERHAPS A PRE-FRONTAL TROUGH MOVES IN DURING
WEDNESDAY, HOWEVER GIVEN RIDGING DOWN TO THE SOUTH THIS BOUNDARY MAY
BE A SLOW MOVER. WE CARRIED CHC POPS SUNDAY NIGHT AS THE
AFOREMENTIONED SYSTEM MOVES THROUGH. WE WILL GO WITH JUST SCATTERED
ACTIVITY FOR NOW, BUT THIS COULD BECOME MORE WIDESPREAD GIVEN THE
LOOK OF THE TROUGH STRENGTH AND MOISTURE ADVECTING NORTHWARD. TO
ACCOUNT FOR SOME POSSIBLE TIMING CHANGES, WE WILL TAPER THE POPS
DOWN SOME MONDAY AND MONDAY EVENING. AN AREA OF WAA SETTING UP TO
OUR WEST MAY BRING IN A CHC OF SOME SHOWERS OR STORMS TO OUR
NORTHWESTERN ZONES TUESDAY WELL AHEAD OF A WARM FRONT. AS A COLD
FRONT THEN GRADUALLY MOVES INTO OUR AREA WEDNESDAY AND THURSDAY, WE
CARRIED SOME SLIGHT CHC TO LOW CHC POPS FOR NOW. AS FOR
TEMPERATURES, WE GENERALLY FOLLOWED HPC GUIDANCE, ALTHOUGH DID MAKE
SOME LOCAL ADJUSTMENTS. MONDAY WILL BE COOLER, HOWEVER THEN THE HEAT
BEGINS TO BUILD ALTHOUGH NO EXCESSIVE HEAT IS ANTICIPATED ATTM.

&&

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

THE COLD FRONT CONTINUES TO SETTLE SOUTHEASTWARD AND STILL HAS TO
CLEAR KMIV AND KACY /AS OF 2320Z/. THE ACTUAL FRONT IS EXPECTED TO
CLEAR THESE TWO TERMINALS WITHIN THE NEXT FEW HOURS. THE DOPPLER
RADAR IMAGERY EARLY THIS EVENING HAS BEEN SHOWING AN OUTFLOW
BOUNDARY, WHICH AS OF 2320Z, WAS DRAPED FROM WEST-CENTRAL NEW JERSEY
THEN CURLED BACK DOWN INTO SOUTHEASTERN NEW JERSEY. ITS WESTWARD
MOTION HAS BEEN SLOWED DUE TO THE NORTHERLY FLOW STRENGTHENING SOME
BEHIND THE FRONT. THE SOUTHERN PART OF THE OUTFLOW BOUNDARY IS GOING
SOUTHWARD AND IS THROUGH KACY AND WILL NEAR KMIV BEFORE PROBABLY
DISSIPATING. ISOLATED CONVECTION HAS BEEN FORMING ON THIS BOUNDARY,
HOWEVER MOST OF THIS ACTIVITY HAS NOT BEEN ABLE TO MAINTAIN ITSELF.
THEREFORE, NO PRECIPITATION WILL BE CARRIED EAST OF THE COLD FRONT
AS ANY RENEWED ACTIVITY SHOULD BE RATHER ISOLATED NOW BEFORE ENDING
COMPLETELY. THE HIGHER MOISTURE CONTENT WILL KEEP SOME LOWER
CEILINGS AND/OR HAZE IN THE VICINITY OF KACY AND KMIV FOR A LITTLE
LONGER THIS EVENING UNTIL THE DRIER AIR INFILTRATES SOUTHEASTWARD.
ELSEWHERE, VFR CONDITIONS ARE EXPECTED AS THE CUMULUS FIELD
CONTINUES TO THIN WITH THE INCOMING DRIER AIRMASS. AFTER A LITTLE
HAZE EAST OF THE COLD FRONT EARLY THIS EVENING, NO VISIBILITY
RESTRICTIONS ARE ANTICIPATED GIVEN THE DRYING THAT IS FORECAST.

THE NORTHERLY FLOW BEHIND THE FRONT WILL ALLOW FOR SOME GUSTS TO
NEAR 15 KNOTS FOR A TIME AT SOME TERMINALS, HOWEVER THIS IS EXPECTED
TO SETTLE SOME THROUGH THE NIGHT. FOR FRIDAY, A NORTH TO NORTHWEST
WIND NEAR 10 KNOTS IS EXPECTED AS HIGH PRESSURE GRADUALLY BUILDS IN.
THERE APPEARS TO BE A RIBBON OF MOISTURE AROUND 5,000 FEET AND WITH
PLENTY OF HEATING, WE CARRIED SOME CUMULUS. SOME LOCALES MAY HAVE
THEIR LOCAL WIND SHIFT MORE FROM THE NORTHEAST, LIKE KTTN AND KACY.

OUTLOOK...
HIGH PRESSURE IN THE AREA FRIDAY NIGHT AND SATURDAY WITH NO
SIGNIFICANT WEATHER EXPECTED. A WEAK AREA OF LOW PRESSURE MOVES INTO
THE AREA DURING SUNDAY WITH THE POTENTIAL FOR BANDS OF SHOWERS AND
THUNDERSTORMS. THERE IS SOME UNCERTAINTY REGARDING THE OVERALL
COVERAGE OF THIS ACTIVITY, HOWEVER AREAS OF REDUCED CEILINGS AND
VISIBILITIES ARE POSSIBLE. WE MAY ALSO HAVE AN EXPANSIVE AREA OF
STRATOCUMULUS FORMING GIVEN THE MOISTENING SOUTHEASTERLY FLOW. THIS
POSSIBLY UNSETTLED WEATHER AT TIMES MAY CONTINUE MONDAY INTO TUESDAY
AS WELL.
-- End Changed Discussion --

&&

.MARINE...
-- Changed Discussion --
NO HEADLINES ATTM. A COLD FRONT MOVES THROUGH THIS EVENING WITH A
WIND SHIFT TO THE NORTH. THE NORTHERLY FLOW WILL GUST AT TIMES
TONIGHT WITHIN DEVELOPING CAA, HOWEVER IT LOOKS MARGINAL ATTM FOR
AN ADVISORY.

NEXT CONCERN IS ELY COMPONENT FLOW SCA FOR SUNDAY/MONDAY PER LOW
PRES TRYING TO DEVELOP NEAR THE NC COAST AS HIGH PRES IS LODGED IN
THE MARITIMES. COOL BL TEMP PERMITS BETTER TRANSFER OF WIND FROM
THE GENERALLY ANOMALOUSLY WARM NJ/DEL OCEAN WATERS. SEAS SHOULD
BUILD TO BETWEEN 4-6 FT AND GUSTS MAY REACH 25 OR 30 KTS BUT THIS IS
PENDING FURTHER REVIEW AS WE DRAW CLOSER TO WHATEVER THIS EVENT
WILL BE.
-- End Changed Discussion --

&&

.CLIMATE...
-- Changed Discussion --
SOLID CONSISTENT SIGNALS ON WARMTH THIS JULY..WITH RESPECT TO THE
PERIOD OF RECORD.

PHL ON TARGET FOR A 2ND WARMEST JULY ON RECORD. THE FIRST 28 DAYS
IN THE BOOKS PLUS THIS MORNINGS LOW AND THE CCF FCST FOR THE
REMAINDER OF THE MONTH WILL GIVE PHL AN APPROXIMATE FINAL OF ~81.5
OR THEREABOUT MONTHLY AVG... SECOND TO THE 82.1 OF 1994 WITH 81.5
OF 1995 CURRENTLY RANKED NUMBER 2.

BELOW IS THE SAME PROCESS AS PHL ABOVE...FIRST 28 DAYS IN THE BOOKS
THIS MORNINGS MIN AND THE REMAINING CCF HI/LOWS FOR THE 29TH-31ST
INCLUDING ANTICIPATED 1AM FRIDAY LOW FOR TODAY-THURSDAY THE 29TH-
CALENDAR DAY.

JULY PROJECTION RANK     POR = PERIOD OF RECORD
KABE 76.7 NOT TOP 10

KILG 79.8 6TH TIED WITH 1994. WARMEST EVER 81.2 1955. POR 1894
KRDG 78.8 6TH TIED WITH 1901. WARMEST EVER 81.5 1955. POR 1898

KACY 80.1 WARMEST MONTH EVER! PREVIOUS WARMEST 78.7 JULY/1983. POR 1874

KTTN 80.5 TIED WARMEST MONTH EVER! WHICH WAS JULY/1955. POR 1893

KMPO 71.8 3RD WARMEST. WARMEST 73.2 1955. POR 1902
KPHL 81.5 2ND WARMEST. WARMEST 82.1 1994. POR 1874
-- End Changed Discussion --

&&

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

&&

$$
SYNOPSIS...MEOLA
NEAR TERM...NIERENBERG/MEOLA
SHORT TERM...MEOLA
LONG TERM...GORSE
AVIATION...GORSE
MARINE...DRAG/GORSE
CLIMATE...DRAG