Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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725
FXUS61 KPHI 260836
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
436 AM EDT THU MAY 26 2016

.SYNOPSIS...
Our region will remain on the western periphery of an area of high
pressure located over the ocean off the east coast through this
weekend. A couple of backdoor cold fronts may approach our area from
the north during that time frame, but should not make much southward
progress. An area of low pressure moving through the southern
Canadian provinces early next week may bring a cold front across our
region by the middle of the week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Prior to sunrise. Fair (variable cirrus). Light southwest or calm
wind.

After sunrise...A second mostly sunny very warm day is ahead with
a few locations in our forecast area likely nudging 90F for the
first time this year including KABE, KRDG, KPNE, KSMQ, KGED but
mainly northward from near PHL along and west of the NJT to KABE
and KRDG. Wind this afternoon south to southwest gusting to 15 mph.
A midday ocean influenced south southeast sea breeze will eventually
lower the near 80F late morning max temps significantly by mid
afternoon. Otherwise, high temps in the interior around 10-13F degrees
above normal. Pops withdrawn from e PA late today and it appears any
showers should develop after 6 pm there, if at all. Not much lift
mechanism despite weak instability burst.

Fcst basis: generally a 50 50 blend of the 00z/26 GFS/NAM MOS
guidance. Have checked all 00z/26 MAX temps tools from MET/MAV,
BIAS adjust of these as well as National and Super blend and basically
raised the highest of the warmest guidance away from the bays and
Atlantic coasts by 1-2F. That means the 89 at KPHL, 84 KMPO, 90 at
KABE and KGED as well as 89 at KFWN are all all fcst above the warmest
guidance...in part due to the initial westerly isobaric flow.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...
Tonight...A small chance of a shower or maybe even an isolated
thunderstorm advancing eastward into our forecast area...toward
midnight, mainly eastern PA and e MD. Guidance lowered toward the
drier MET/ECMWF/UKMET guidance. Am not expecting much and my
confidence on any rain occurrence tonight is below average.
(00z/26 SPC WRF n/a but NSSL WRF was quickly reviewed).

A milder night than what is occurring early this Thursday morning.
Min temps around 10-13 degrees above normal.

Fcst basis was a 50 50 blend of 00z/26 GFS/NAM guidance except
favored the drier 00z/NAM MET pop guidance.

&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
The main story will be above average temperatures thru the period as
well as some uncomfortable humidity levels late this week into
early next week. The warmest days are expected to be Friday thru
Sunday, with temperatures near 90. In fact, Sunday may be the
hottest day, and we bumped temperatures up several degrees to near
90, but would not be surprised to see lower 90s.

The main uncertainty will be the interaction between an approaching
cold front early next week and an early season tropical/sub-tropical
system modeled to develop in the Bahamas. The model solutions vary,
but at least some moisture is expected to make it into our region
by Monday, when there is a better chance for more widespread precip.
Otherwise, there is a chance of diurnally driven showers and
thundershowers Friday thru Sunday, particularly northwest of I-95.

There may be a cold frontal passage in the Tuesday-Wednesday time
frame, with the ECMWF most progressive with this feature. This
would lead to a drying trend during this period, but the front
may stay to our north, which would continue the chance of showers
and thundershowers.

&&

.AVIATION /08Z THURSDAY THROUGH MONDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY and surrounding areas.

Through 12z...VFR with variable cirrus. Small chance of isolated
MVFR VSBY near 10z vcnty KRDG or KMIV but dewpoints are so low
that fog is unlikely. Light south to southwest wind.

After 12z Today...VFR. Sct clouds aoa 6000 ft, mainly this
afternoon. South to southwest wind should gust 15 kt this
afternoon.

Tonight...VFR sct-bkn aoa 6000 ft. Small chance of a shower or
isolated tstm near 06z/27...mainly KRDG, KABE after 03z/27.

OUTLOOK...
Predominantly VFR during the day through the period, with MVFR
possible in some fog development Saturday night thru Tuesday
night.

&&

.MARINE...
No marine headlines anticipated through Tonight.

Southwest winds with scattered gusts 15 kt this morning become
south to southeast this afternoon, also with gusts to 15 kt...then
return to southwest overnight-this coming Thursday night.

Seas aob 3 feet. Used the latest available more conservative NWPS
guidance (25/18z run).

OUTLOOK...
Winds may gust to near 20 knots Friday through Saturday, but
are expected to remain below SCA criteria at this time. Otherwise,
sub-SCA conditions are anticipated for the remainder of the
period.

RIP CURRENTS: We are forecasting a low risk for the formation of
dangerous rip currents,  with potential near moderate risk along
northern ocean county and monmouth county this afternoon where the
southeast southeast wind may be a little stronger.  Since it will
be another very warm day, and many if not all beaches are unguarded,
swimming is not advised.  yesterday there was a fatality nearby
just to our north.  Fatalities can easily happen at unguarded
locations.  water temperatures are not especially warm...close to
60F which is near or slightly below normal. If going to the
beach today...be safe.

&&

.CLIMATE...
The Philadelphia monthly average temperature continues to project
only about 1f below normal... with this current end of the month
stretch of above normal temperatures denting the first 24 days,
nearly 4 degree below average.

Also the Philadelphia month of May precip total of 5.14 inches
ranks 20th wettest dating back to 1872. Atlantic City has had 4.87
is ranked #21 wettest dating back to 1874 and Wilmington`s (DE)
5.55 inches ranks 18th dating back to 1894.

Finally, preliminary precipitation estimates for Allentown (ABE) are
on pace for a top ten driest meteorological spring, in the absence
of significant rainfall over the next six days. The average spring
rainfall for ABE is 11.09 inches, with 5.84 inches as of 5/25. If
less than 1.63 inches of rain falls for the remainder of May, ABE
will be at least within the top ten.

&&

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

&&

$$
Synopsis...Franck/Robertson
Near Term...Drag
Short Term...Drag
Long Term...Franck
Aviation...Drag/Franck
Marine...Drag/Franck
Climate...Drag/Franck



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