Warminster, Pennsylvania 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

261
FXUS61 KPHI 200052
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
852 PM EDT Mon May 19 2025

.SYNOPSIS...
High pressure will build across the area into Tuesday. A dynamic
weather system will approach the region towards the middle of the
week, bringing another period of unsettled weather. The system`s
upper level low will linger nearby into next weekend.

&&

.NEAR TERM /THROUGH TUESDAY/...
Fair weather continues overnight with high pressure building in.
Now that the best mixing has diminished, winds will decrease to
around 10 mph or less with skies becoming mainly clear across
the area. Temperatures will be cooler though as Canadian high
pressure begins to settle into the area. Lows fall into the 40s
for most locations, with some upper 30s possible in the southern
Poconos. No frost development is expected in the Poconos though
as dew points will be in the low 30s, meaning it will be too
dry for frost to develop.

For Tuesday, the high will become centered very close to the region.
This will result in a day very similar to Monday as far as
temperatures go (highs in the mid 60s to low 70s) but with notably
lighter winds. Skies will be mostly sunny to begin the day but in
the afternoon, and particularly the evening, high clouds will
increase as the next low pressure system begins to approach the
region.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/...
Quite unsettled weather begins Tuesday night. In the upper-levels, a
trough is digging into the Great Lakes and becomes closed off into
an upper-level low over the Northeast by Thursday. At the surface, a
low pressure system moves northward from the southwest. This main
low fizzles out southeast of the Great Lakes and a new low forms off
the Mid-Atlantic Coast Wednesday night into Thursday. This low
becomes our main feature and deepens as it moves northeast away from
our area.

As a result of this set-up, clouds thicken into Tuesday night.
Widespread rain arrives early Wednesday morning. We see this
widespread rain continue through Wednesday into Thursday evening.
There is a signal there for frontogenetic banding on Wednesday
which would add enhancement to the rainfall leading to pockets
of moderate to heavy rain at times. An embedded thunderstorm is
also possible. By Thursday evening, rainfall amounts look to
generally be around 1 to 1.5 inches with locally higher amounts
possible. Fortunately this will be more of a stratiform type
rain with these amounts falling over a period of 24+ hours so we
aren`t thinking major hydro concerns at this time, though it
will need to be watched. Nuisance type poor drainage type
flooding will certainly be possible and also worth noting, the
Weather Prediction Center has the area in a MARGINAL (1/4) risk
for excessive rainfall for the period Wednesday through
Wednesday night. Winds will also pick up as the low deepens off
the coast. Wind gusts will reach 25-35 mph at times Wednesday
night into Thursday morning. Gusts will still be around or over
20 mph through much of Thursday. The rain and the marine
influence will keep it cool for Wednesday with highs mainly in
the 50s to low 60s. Lows Wednesday night then drop into the 40s
to low 50s. Another cooler day on Thursday with highs mainly in
the low 50s to low 60s.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
As the low off the coast exits Thursday night, some showers linger.
The bulk of the rain will be gone though. The upper-level low will
continue to be placed over the Northeast which keeps things
unsettled Friday and Saturday. Isolated to scattered showers move
through both days. By Sunday, we still can`t completely rule out a
few showers but the trend will be towards drier, sunnier weather
with moderating temperatures.

&&

.AVIATION /01Z TUESDAY THROUGH SATURDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY and surrounding areas.

Tonight...VFR with skies becoming clear. North-northwest winds
around 5-10 kt, decreasing to less than 5 knots after midnight,
particularly for more sheltered terminals. High confidence.

Tuesday...VFR with increasing high clouds after 18Z. North-northwest
winds around 5-10 knots. High confidence.

Outlook...

Tuesday night through Thursday...Sub-VFR conditions probable with
rain likely.

Friday through Saturday...Sub-VFR conditions possible at times with
occasional showers.

&&

.MARINE...

Winds continue to subside. The SCA flag was dropped at 6PM. North
to northwest winds of 10 to 15 kts will continue tonight with a
couple gusts up 20 kt possible early. Winds then decrease to around
10 knots for Tuesday. Seas of 2-3 feet and fair weather throughout
the period.

Outlook...

Tuesday night...No marine headlines expected.

Wednesday through Friday...SCA conditions probable due to wind gusts
around 25-30+ kts and seas building to 7-9 feet. It`s even possible
there could be a period of Gale conditions late day Wednesday into
Thursday.

Rip Currents...

For Tuesday, northwest winds will be around 15 mph then become
southeast around 5 to 10 mph with a 6-7 second period and
breaking waves around 1-2 feet. A LOW risk for the development
of dangerous rip currents is in place for all beaches.

For Wednesday, east winds will increase to 10-20 mph with a 6-7
second period and breaking waves around 2-4 feet. A MODERATE
risk for the development of dangerous rip currents is in place
for all beaches.

For specific beach forecasts, visit weather.gov/beach/phi

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...None.
NJ...None.
DE...None.
MD...None.
MARINE...None.

&&

$$

SYNOPSIS...Guzzo
NEAR TERM...AKL/po
SHORT TERM...Guzzo
LONG TERM...Guzzo
AVIATION...AKL/Guzzo/po
MARINE...AKL/Guzzo/RCM/po