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fxus61 kphi 180539 
afdphi

Area forecast discussion
National Weather Service Mount Holly New Jersey
1239 am EST sun Feb 18 2018

Synopsis...
low pressure will continue to quickly move away from our area
overnight. High pressure briefly builds across the area again
on Sunday, then offshore Sunday night. A strong warm front lifts
northward across our area later Monday into early Tuesday,
followed by a cold front late Wednesday. The cold front stalls
to our south by next Thursday with a series of waves moving
north and east along it late next week into early next weekend.

&&

Near term /until 6 am Sunday/...
the remaining winter weather headlines have been cancelled.
Watch for some slippery spots though on untreated surfaces.

Low pressure continues to rapidly move away from our area. As a
result, the precipitation has quickly ended across the northern
areas, although a few light snow showers will be possible for a
few more hours. Lots of low clouds remain with weak surface
winds, however as drier air arrives later tonight the clouds are
expected to lift and start to thin. In addition, some fog around
is also expected to improve. Made some adjustments to the hourly
temperature, dew point and wind grids.

&&

Short term /Sunday/...
high pressure is forecast to build into our region from the
west for Sunday. We are anticipating a mostly sunny day with a
northwest to west wind around 10 miles per hour.

Sunday afternoon is expected to become relatively mild. Highs
are forecast to be in the lower and middle 40s in the Poconos,
the Lehigh Valley and northern New Jersey. Readings should get
into the upper 40s and lower 50s in northeastern Maryland,
Delaware, southeastern Pennsylvania, and southern and central
New Jersey. Much of the new snow cover should melt by day's end.

&&

Long term /Sunday night through Saturday/...
**record warmth possible Tue and expected wed**

Sunday night through Wednesday....

To start the period Sunday evening, high pressure crests over
the area in the evening before slowly moving east overnight.
This will set up good conditions for radiational cooling due to
light winds and mainly clear skies despite the airmass not being
all that cold. Lows by Monday morning should generally be in
the 20s to low 30s.

For Monday, the high continues to push off to the east through
the day with a warm front approaching from the south and west
ahead of the next system. This will bring increasing clouds with
some showers likely by afternoon...mainly over eastern PA.
Highs will generally range from the mid 40s north to the 50s
across the Delmarva and southern New Jersey.

Some showers may continue into Monday evening before lifting
out overnight as the front moves through. Temperatures will be
quite mild with lows only dropping to the 40s to low 50s. This
will be followed by near record warmth on Tuesday as a strong SW
flow takes hold. We continue to forecast temperatures above the
model consensus and are generally looking at highs ranging from
the 60s in the north to the low 70s across southeast PA as well as
much of the Delmarva and southern New Jersey. Areas right near the coast
will likely be cooler though.

For Tuesday night into Wednesday, temperatures continue to warm
with record warmth forecast by Wednesday...highs currently
forecast to reach the low to mid 70s over southeast PA as well as much
of the Delmarva and New Jersey. Conditions should be dry for the most
part though by late Wednesday a cold front could bring some
showers in from the west...mainly for eastern PA.

Wednesday night through Saturday...

In the big picture, this period will be dominated by somewhat
cooler, though still well above average temperatures as a long
wave trough persists over the Rocky Mountains with the area in a
SW flow. Conditions will also trend more unsettled as a series
of waves move north and east along a wavering front that will
linger in the region.

For Wednesday night into Thursday, the aformentioned cold front
with some associated rain showers pushes south through the area
before stalling over the mid Atlantic. Forecast guidance then
indicates a wave trying to move north along the front though
there is uncertainty in how this all evolves as high pressure
will also be building in to our north. The high could suppress
precip mainly to our south into Thursday but again, these
details are uncertain so we keep chances for showers in the
forecast through Thursday. Beyond this time there may be a brief
break before a stronger low pressure system moves north along
the front by later Friday into next Saturday. Highs Thursday and
Friday will generally be in the 40s and 50s with 60s possible
again by next Saturday.

&&

Aviation /06z Sunday through Thursday/...
the following discussion is for kphl, kpne, kttn, kabe, krdg,
kilg, kmiv, kacy and surrounding areas.

Overnight...MVFR/IFR conditions improving to VFR late. Light and
variable winds becoming northwest 5-10 knots late.

Sunday...VFR. Northwest wind around 10 knots.

Outlook...
Sunday night...VFR. Confidence: well above average.

Monday...VFR early, lowering to MVFR or IFR during the
afternoon or evening with rain. South to southwest wind.
Confidence: above average.

Monday night...MVFR/IFR conditions continue with rain possible
in the evening, and low clouds/dense fog possible overnight.
Confidence: above average.

Tuesday...MVFR/IFR conditions possible through midday in low
clouds/fog. Conditions improving to VFR during the afternoon.
Southwest winds may gust around 20-25 knots in the afternoon.
Confidence: average.

Tuesday night...VFR early, then possibly lowering to MVFR/IFR
as low clouds/fog may develop overnight. Confidence: average.

Wednesday...MVFR/IFR conditions possible early with low
clouds/fog. Conditions improving to VFR during the day. Chance
of showers late in the day. Southwest winds may gust around
20-25 knots. Confidence: average.

Wednesday night through Thursday...chance of showers with
associated restrictions. Confidence: below average.

&&

Marine...
low pressure will continue to quickly move away from our area
overnight. A gusty northwest wind is expected to develop on the
coastal waters of New Jersey and Delaware in the wake of the
low. As a result, we will issue a Small Craft Advisory for our
ocean waters and for Delaware Bay. It will be in effect from
4:00 am until 11:00 am Sunday. The wind is forecast to diminish
gradually on Sunday afternoon.

Outlook...
Sunday night through Monday...sub Small Craft Advisory south
winds. Confidence: well above average.

Monday night...sub Small Craft Advisory conditions expected,
although southwest winds may gust around 20 knots. Confidence:
above average.

Tuesday-Wednesday...winds should stay below advisory levels,
but seas may increase to near 5 feet. Confidence: average.

Wednesday night - Thursday...winds should stay below Small Craft Advisory levels
with seas persisting in the 3 to 5 foot range.

&&

Climate...
record high temperatures could be challenged on Tuesday,
February 20th and probably will be equaled or exceeded Wednesday
February 21st. These records are listed below.

February 20:

Atlantic City...70 in 1930

Philadelphia....70 in 1939

Wilmington......71 in 1930

Allentown.......68 in 1930

Trenton.........70 in 1930

Georgetown......68 in 2002

Mount Pocono....59 in 1930

Reading.........72 in 1930



February 21:

Atlantic City...74 in 1930

Philadelphia....72 in 1930

Wilmington......70 in 1953

Allentown.......67 in 1953

Trenton.........70 in 1930

Georgetown......71 in 2014

Mount Pocono....60 in 1930

Reading.........71 in 1930



We are not posting the monthly records at this time since our
forecast is 3 to 7 degrees below the monthly record. We'll check
again Sunday and Monday to see if our forecast edges warmer.

The following are the record warm mins for Wednesday Feb 21.
Barring a sudden immediate cool down behind the cool front at
1159pm Wednesday, there is a good chance of record warm daily
minimum temperatures as well the previously referenced record
highs.

Record high mins for 2/21

Abe 46-1981
Acy 49-1954
phl 49-2002
ilg 47-2002
ridge 48-1930
ttn 48-2002

Atlantic City rainfall already ranks 11th wettest in February
history with 6.50" in 2010 the wettest. By sunrise Sunday,
Atlantic City should rank about 8th wettest in its historical
database.

The February average temp for phl projects 41.0 or 5.3f above
normal or 8th warmest on record. This placement can change
anywhere from 3rd to 12th depending on a 1 degree change in the
eventual average. Bottom line...we're likely on our way to a top
10 warmest February on record. The warmest was last year with a
44.2f average. Years 2002 and 2012 flank our currently
projected 8th warmest.

&&

Phi watches/warnings/advisories...
PA...none.
New Jersey...none.
Delaware...none.
Maryland...none.
Marine...Small Craft Advisory from 4 am to 11 am EST this morning for
anz430-431-450>455.

&&

$$
Synopsis...fitzsimmons
near term...amc/gorse

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