085
FXUS61 KPHI 081737
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
1237 PM EST Wed Jan 8 2025

.SYNOPSIS...
Arctic high pressure well to our west will gradually build into
our region thru the end of the week and also weaken. An area of
low pressure is forecast to develop near the Texas Gulf coast
Thursday and track east or northeast and then exit off the Mid-
Atlantic coast during Saturday. High pressure then arrives for
Sunday, followed by a cold front early next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
The synoptic setup remains the same as yesterday with high
pressure well to the west and a strong low over the Canadian
Maritime provinces. A moderate NW flow between the systems
continues to bring in cold, dry air to the Middle Atlantic
region. Skies are expected to be clear or partly cloudy for most
areas, but some moisture from the Great Lakes will produce
clouds which edge into the southern Poconos and north NJ at
times. A couple light flurries may occur with these clouds this
morning.

High temperatures will be similar to what we had yesterday with
mostly low 30s S/E and 20s N/W. Winds will remain gusty today
so wind chill readings will be unpleasant with values mostly 0
to 10 degrees. Below zero wind chills expected across the
highest elevations N/W (Mount Pocono). Winds will be 15 to 25
mph with gusts over 30s mph at times. Tonight, lows will settle
into the teens for most areas and single digits across the N/W.
It looks like wind chills around -15 tonight for Mount Pocono.
We`ll go with a Cold Weather Advisory for Carbon and Monroe PA.

&&

.SHORT TERM /THURSDAY THROUGH SATURDAY/...
The main story Thursday is the continued wind. With surface low
pressure expected to remain near Nova Scotia and high pressure
building east across the Corn Belt, the pressure gradient will
actually tighten up again, with winds ramping back up compared
to what we expect today. Gusts will be 35-40 mph across much of
the region, possibly touching 45 mph in the Poconos. Otherwise,
still cold with highs mostly in the low 30s, but a touch milder
than today.

Winds start a steadier relaxation trend Thursday night as high
pressure continues building eastward toward us from the Ohio
Valley, so we should see a notable decline in gusts as the
gradient starts to relax more. Lows in the teens and 20s with
wind chills in the single digits, but a few degrees above what
we expect tonight.

A more notable, if brief, moderating trend occurs Friday as the
high moves overhead, winds relax but the sun stays around until
afternoon. Highs likely reach the mid 30s across much of the
region, and with lighter winds, it will feel considerably warmer
than the prior two days.

From there, the main focus shifts to the potential for a little
wintry weather Friday night into Saturday. Guidance has
congealed more closely around the weak/southern low track with
only a bit of light snow affecting our region. Most models do
show some light precip across the region, associated more with
the northern piece of energy than the coastal low, but either
way, did include likely pops for snow later Friday night into
Saturday morning. However, accumulations at best look like an
inch or two, so possibly a low-end advisory event across our
southeastern zones of NJ and DE. Elsewhere, likely an
essentially non-event. After lows in the 20s Friday night, highs
return to the 30s for Saturday as the clouds break for some sun
later in the day.

&&

.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
A few days of relatively relaxation from the cold occur Sunday
and Monday with high pressure returning to the region, but with
much less cold advection and a much weaker pressure gradient,
resulting in notably milder wind chill temperatures and slightly
milder air temperatures. Dry conditions prevail Sunday and
Monday. A relatively weak system then may cross the region
Tuesday, with a small chance of snow showers and some
reinvigorated winds.

&&

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Today... VFR expected with SCT/BKN skies at most sites.
Increasing W or NW winds after sunrise with gusts 25 to 30 kts
at all sites during the daylight hours. High confid.

Tonight...VFR. Clear skies expected. W or NW winds decreasing
but still gusty to 20 kts at times. High confid.

Outlook...

Thursday through Friday...VFR. Gusty northwest winds up to 35
kts Thursday drop back to 30 kts Thursday night and below 25
kts Friday.

Friday night through Saturday...Sub-VFR possible due to some
snow.

Saturday night and Sunday...returning to VFR.

&&

.MARINE...
Gale Warning in effect today and tonight for NW winds gusting
35 to 40 kt. Seas 4 to 7 feet. The strong winds, cold
temperatures, and choppy seas will create light freezing spray
at times today and tonight.

Outlook...

Thursday and Thursday night...Gales likely to continue into
Thursday night with wind gusts to 35 kt. Wave heights up to 7
feet. Freezing spray possible.

Friday...Winds drop to Small Craft Advisory levels with seas
dropping below.

Friday night...Winds and seas drop below SCA levels, but snow is
possible.

Saturday...Winds ramp back up to SCA levels with snow possible.

Saturday night through Sunday...SCA conditions likely with
freezing spray possible.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...Cold Weather Advisory from 7 PM this evening to 10 AM EST
     Thursday for PAZ054-055.
NJ...None.
DE...None.
MD...None.
MARINE...Gale Warning until 6 PM EST Thursday for ANZ430-431-450>455.

&&

$$

SYNOPSIS...OHara/RCM
NEAR TERM...DeSilva/OHara
SHORT TERM...RCM
LONG TERM...RCM
AVIATION...DeSilva/OHara/RCM
MARINE...DeSilva/OHara/RCM