Chester, Pennsylvania 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

096
FXUS61 KPHI 051623
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
1223 PM EDT Sun Apr 5 2026

.WHAT HAS CHANGED...
Updates for frontal passage across the area today.

&&

.KEY MESSAGES...
1. Fog and low stratus lingers this morning as the backdoor
front crawls north ahead of an advancing cold front that will
bring a round of showers and thunderstorms.

2. Fire weather conditions possible on Monday and Tuesday.

3. Chilly temperatures Wednesday morning and Thursday morning may
affect the beginning of the growing season, where the growing season
is currently active.

&&

.DISCUSSION...
KEY MESSAGE 1...An advancing cold front that will continue to
bring showers and perhaps a thunderstorm.

A line of showers and thunderstorms is crossing the forecast
area as of the noon hour. Mostly heavy showers, but some lightning
across parts of ern PA and into North NJ. No warnings have been
issued as of now, and it appears that this will remain the case
today. The SPC has a Marginal Risk for severe weather across
Delmarva for today. Showers are expected to drop around 0.50-0.75
inches of rain across the region, with areas south and east seeing
the best chances for heavier rainfall and thunderstorms. Clouds
will diminish from North/West to South/East thru the afternoon.
Gusty West winds will develop too with speeds 10 to 15 mph and
gusts to around 25 mph at times.

Behind the cold front, temperatures will take a modest fall, with
overnight lows expected to dip into the mid 30s to low 40s; areas
across the Poconos could reach freezing. WNW winds will also gust to
around 15-20 mph for a period overnight.

KEY MESSAGE 2...A slight risk of fire spread is possible on Monday
and Tuesday.

A period of fire weather conditions is possible on Monday, but more
so on Tuesday as a dry airmass infiltrates the area. MinRH values
will be in the 30-40% range across much of the area for Monday
afternoon with westerly winds around 10-15 mph and gusts up to 20-25
mph. By Tuesday morning, a secondary cold front is forecast to pass
through the region. This will cause dew points to fall into the
teens. MinRH values will be in the 25-35% range with northwest winds
around 15-20 mph and gusts up to 30-35 mph.

At this time, these conditions do not meet Red Flag Warning criteria
on Monday, but will be close on Tuesday. Depending on how dry fuel
moisture are across the region, we may need to consider a Special
Weather Statement for an increased risk of fire spread. We will be
in contact with our partners at a later time to determine if a SPS
is warranted.


KEY MESSAGE 3...Chilly temperatures Wednesday morning and Thursday
morning may affect the beginning of the growing season, where the
growing season is currently active.

Strong Canadian 1040 mb high pressure will settle over New York
State on Wednesday morning before shifting off the New England coast
by Thursday morning. In wake of a cold front on Tuesday, a
reinforcing shot of cold, dry air will arrive Tuesday night and
linger into Wednesday night. Low temperatures will fall into the low
to mid 20s to low to mid 30s for most locales, with teens in the
Poconos by Wednesday morning. Considering that the growing season is
now active across portions of the Delmarva, patchy areas of frost
are possible. However, with such a dry airmass in place, frost
formation may be limited.

Temperatures will be somewhat similar for Thursday morning, but with
the high shifting offshore, lows should be a few degrees warmer than
Wednesday. With closer dew point depressions expected for Thursday
morning, suppose more patchy frost is possible. Will continue to
monitor forecast trends and evaluate if any frost headlines may be
warranted in the coming days.

&&

.AVIATION /16Z SUNDAY THROUGH THURSDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

This afternoon... Showers and and a few tstms crossing the area
attm. CIGs/VSBYs haven`t lowered too much with the line with
mainly MVFR and a couple short periods of lower. Conditions will
improve back to VFR from N/W to S/E this afternoon. Winds West
to Northwest at 10 to 15 kts with gusts to 25 kts at times.
Moderate confidence.

Sunday night... Except for any lingering showers across southern NJ
or Delaware during Sunday evening, mostly VFR is expected. Patchy
rural fog possible Monday morning. Moderate confidence.

Outlook...

Monday through Tuesday...VFR. Gusty winds up to 20 kt possible on
Monday with gusty winds up to 25-30 kt possible on Tuesday.
Otherwise, no significant weather.

Tuesday night through Thursday...VFR. No significant weather
expected.

&&

.MARINE...
SCA conditions through tonight. A cold front will push across
the waters this afternoon, shifting winds WNW behind it. There
may be a lull in winds immediately behind the front, but winds
overnight will ramp back up to 20-25 kts. Seas will stay
elevated around 4-6 feet.

Outlook...

Monday through Monday night...No marine headlines expected. Winds
generally 20 kt or less and seas of 2-4 feet.

Tuesday...Small Craft Advisory conditions possible with winds
gusting around 25 kt.

Tuesday night through Thursday...No marine headlines expected. Winds
generally 20 kt or less and seas of 2-4 feet.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...None.
NJ...None.
DE...None.
MD...None.
MARINE...Small Craft Advisory until 2 PM EDT this afternoon for ANZ430-
     431.
     Small Craft Advisory until 6 AM EDT Monday for ANZ450>455.

&&

$$

DISCUSSION...DeSilva/MJL/po
AVIATION...DeSilva/MJL/po
MARINE...DeSilva/MJL/po