778
FXUS61 KPHI 181832
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
232 PM EDT Fri Apr 18 2025

.SYNOPSIS...
A warm front will lift northward across the area tonight.
Southerly return flow will then set up across the east coast,
before a cold front tracks through the area Saturday night.
Another cold front will follow on Monday night. High pressure
takes shape through mid-week, with low pressure approaching from
the west by the end of the week.

&&

.NEAR TERM /THROUGH SATURDAY/...
Very warm day ongoing as modest southwesterly flow and warm air
advection has set up with high pressure offshore and an area of low
pressure moving into the Great Lakes. The region gets even warmer
tomorrow with a warm front lifting through later today into tonight.
Not much else going on through the afternoon other than some passing
high clouds ahead of the next system.

For tonight, cloud cover increases which will keep things on the
milder side, in addition to the passing warm front. Temperatures
won`t drop much and lows will end up much warmer compared to
previous nights. A very mild night overall with lows in the upper
50s/low 60s.

For tomorrow, while skies will be partly to mostly cloudy,
temperatures will soar into the low to mid 80s. Gradient remains
tight, which will result in a southwesterly breeze and gusts 20-30
MPH or so. A cold front approaches late in the day, which could
touch off a few showers and isolated thunderstorms, mainly in the
Lehigh Valley and Poconos, though not expecting any severe
weather.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
Some potential will remain for a passing shower or
thundershower tomorrow evening across the Lehigh Valley
northward, but most of the area should remain dry. A cold front
will pass through during the overnight hours, bringing
northwesterly wind and cooler temperatures. Temperatures Sunday
morning look to be mostly in the 50s and 60s, with not a lot of
warming through the day. All-in-all, temperatures Sunday still
look to be 10-15 degrees colder than on Saturday.

High pressure should briefly settle into the region through Monday
with periods of mixed clouds and sun and continued cooler
temperatures (though close to normal for this time of year).

Monday night, another low pressure system will pass to our north
with the associated trailing cold front passing through our area. As
it stands right now, this system looks a little more likely to bring
rain showers (and perhaps a rumble of thunder) with chance PoPs
areawide.

&&

.LONG TERM /TUESDAY THROUGH THURSDAY/...
Some showers could linger into the day on Tuesday, but once any
showers depart the area, conditions through Thursday look to feature
surface high pressure with dry and warm conditions (lows in the 40s
and 50s, highs generally in the 70s). Rain chances look minimal
through this time period.

Towards the end of the week, there are indications that mid-level
ridging over the Northeast will begin to break down, potentially
allowing a more active upper-level pattern to take shape. This could
lead to increasing rain and perhaps thunderstorm chances across the
area for Friday and beyond.

&&

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

Rest of Today...VFR. South/southwest winds 10-15 kt gusting 20-25
kt. High confidence.

Tonight...VFR. South/Southwest winds around 10-15 kt. Period of LLWS
expected overnight with a brisk 40-45 kt southwesterly low-level jet
moving overhead. High confidence.

Saturday...VFR. Southwest winds 10-15 kt, gusting 20-25 kt. High
confidence.

Outlook...

Saturday night...Mainly VFR. Brief periods of sub-VFR
conditions can`t be ruled out in the evening for northwestern
terminals in isolated showers.

Sunday through Monday...VFR. No significant weather expected.

Monday night...Periods of sub-VFR conditions are possible in
scattered showers.

Tuesday...Periods of sub-VFR conditions possible in lingering
showers early. Otherwise, VFR with no significant weather expected.

Wednesday...VFR. No significant weather expected.

&&

.MARINE...
A Small Craft Advisory is in effect for all ocean zones through
06Z Sunday, and for the Delaware Bay through 00Z. Southwesterly
gusts 25-30 kt and seas 4 to 7 feet are expected.

Outlook...

Sunday through Monday...Sub-SCA conditions expected.

Monday night into Tuesday...A cold frontal passage will bring gusty
winds and elevated seas, but for now it appears that conditions will
remain below SCA criteria.

Wednesday...Sub-SCA conditions expected.

&&

.FIRE WEATHER...
On Saturday, Min RH values will be 40 to 45 percent with SW
winds 15 to 20 mph with 25 to 30 mph gusts. On Sunday, Min RH
values will be 30 to 35 percent with NW winds 10 to 15 mph with
gusts up to 20 mph.

&&

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

&&

$$

SYNOPSIS...Cooper/Guzzo
NEAR TERM...Hoeflich
SHORT TERM...Cooper
LONG TERM...Cooper
AVIATION...Cooper/Hoeflich
MARINE...Cooper/Hoeflich
FIRE WEATHER...