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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KPHI 182015
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
315 PM EST Tue Feb 18 2020

.SYNOPSIS...
Low pressure will move through to our north tonight through
Wednesday dragging a cold front through the region. High
pressure builds in behind the front and dominates through the
weekend. The next low pressure system looks to affect the region
early next week.

&&


.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
Low pressure is forecast to move northeastward across southern
Quebec tonight. The low is expected to pull a cold front through
our region from northwest to southeast in the 10:00 pm to 2:00
am time frame.

Clouds will overspread our entire region this evening, as the
cold front approaches. Rain showers will be on the increase, as
well. Rainfall totals for this event will be rather light with
most locations receiving a tenth of an inch or less.

Once the cold front passes off the coast, some clearing will
begin to work its way down from the northwest late tonight. Low
temperatures are anticipated to range from the upper 20s on the
Pocono Plateau to near 40 in northeastern Maryland, Delaware and
southern New Jersey.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/...
High pressure will begin to build into our region from the west
on Wednesday. Any lingering cloud cover over northeastern
Maryland, Delaware and southern New Jersey will drift to our
southeast during the course of the morning.

A northwest wind is forecast to increase to 10 to 15 mph with
gusts around 20 or 25 mph. High temperatures will likely be in
the 40s, with readings not getting above the 30s in the elevated
terrain.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
Expect generally quiet weather over the rest of this week
heading into the weekend. Behind Wednesday`s front, it will be
fairly cold for Wednesday night and Thursday as cold high
pressure builds south across the CONUS. Expect temperatures
running a little below average. There is a system to our south
that will have to be watched but indications are a fairly zonal
flow will keep this system south of us as it makes its closest
pass late Thursday into Thursday night. This will keep it mainly
dry but with increasing cloud cover. The zonal flow breaks down
as an upper level trough tracks through early Friday however,
the high pressure system still remains over the area so this
will keep conditions dry with mainly clear skies.

The dry weather continues through the weekend with the next
potential system arriving early next week. Deterministic
guidance still leaves a bit to be desired with regards to
consistency in timing. However the general idea is that we will
see a low pressure system bring some precipitation into the
region mainly in the form of rain.

&&

.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Tonight...Conditions lowering to MVFR this evening in light
rain showers. There is a chance of brief IFR ceilings especially
around KRDG and KABE. VFR conditions should return after about
04Z. South to southwest wind 5 to 10 knots, becoming northwest
around 10 knots with the arrival of a cold front from the
northwest between 03Z and 05Z. Medium to high confidence.

Wednesday...VFR with scattered clouds. Northwest wind 10 to 15
knots with gusts around 20 knots. High confidence.

Outlook...

Wednesday night through Saturday...VFR with NW winds generally
5-10 knots shifting to westerly on Saturday. High confidence.

Sunday...VFR with SW winds around 5 knots. High confidence.

&&

.MARINE...
A southerly wind around 10 knots into this evening is forecast
to shift to the northwest 10 to 15 knots with the arrival of a
cold front after midnight. A northwest wind 10 to 15 knots with
gusts around 20 knots is expected for Wednesday.

A persistent easterly swell has resulted in the development of
4 to 6 foot waves on the coastal waters of New Jersey and
Delaware. The swell is forecast to be slow to subside, so we
have extended the Small Craft Advisory until 6:00 am Wednesday
and we have included our ocean waters off both Delaware and New
Jersey. It appears as though the swells will subside enough on
Wednesday morning to allow wave heights to diminish to 3 to 4
feet at that time.

Outlook...

Wednesday night through Thursday...Northwest winds continue
behind a cold front with these winds becoming more northerly
through Thursday. Speeds will generally be around 10 to 15 knots
with gusts up to 20 knots. Seas generally 2 to 4 feet or less.

Thursday night through Friday...SCA conditions possible for a
time as northerly winds increase to around 20-25 knots later
Thursday night into early Friday. Seas 1-3 feet Thursday night
increasing to 2-4 feet Friday.

Friday night through Sunday...Sub SCA conditions expected but
west winds may gust up to 20 knots through Saturday before
diminishing by Sunday.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...None.
NJ...None.
DE...None.
MD...None.
MARINE...Small Craft Advisory until 6 AM EST Wednesday for ANZ450>455.

&&

$$

Synopsis...Fitzsimmons
Near Term...Iovino
Short Term...Iovino
Long Term...Deal/Fitzsimmons
Aviation...Fitzsimmons/Iovino
Marine...Fitzsimmons/Iovino