Tredyffrin, Pennsylvania 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

148
FXUS61 KPHI 111403
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
1003 AM EDT Fri Apr 11 2025

.SYNOPSIS...
A low pressure system moves into the forecast area Friday and
lingers through Saturday. This will result in below normal
temperatures as well as some wet weather. The system will move
east over the Atlantic on Sunday, allowing high pressure to
move into the region and remain in place through most of Monday,
providing us with moderating temperatures. A cold front will
move through the region later on Tuesday. The will result in
below normal temperatures on Wednesday. The region could see a
slight warmup on Thursday ahead of the next system to close out
the work week.

&&

.NEAR TERM /THROUGH TONIGHT/...
Late morning update to include a mention of fog in the southern
Poconos through much of the day. This seems to be limited to the
higher terrain, and with more rain moving in, especially this
afternoon, don`t expect the extent of fog to increase.
Otherwise, no significant changes.

For today, an area of low pressure over the Carolinas will
organize and move up the coast. This will result in a cloudy and
overcast day with occasional showers in the morning, with more
widespread and steady rain for the afternoon and evening as the
surface low approaches. There could be a rumble of thunder mixed
in, mainly for South Jersey and Delmarva, but no severe weather
is expected. The low will be off the Delmarva coast after
midnight and will meander there through the rest of the
overnight hours. The surface low, while gradually strengthening,
won`t be overly strong, which will result in a less impactful
system. We will have a decent onshore breeze with gusts up to
30-35 MPH or so. Rainfall amounts will end up ranging from 1-2
inches for the Friday- Saturday period. However, even as the
bulk of the rain comes this evening/tonight, flooding concerns
are minimal as rates won`t be very impressive. Overall, this
system looks to be a breezy beneficial rain.

One thing to note is that another round of snow is likely
tonight as thermal profiles look to be just cold enough to
support flakes at the higher elevations. Accumulations up to an
inch are expected for the Pocono Plateau, with perhaps a tenth
or two at higher points in Northwest NJ. Any snow this morning
will change to rain by the mid-morning, and then change back to
snow late tonight/early tomorrow morning.

Temperatures today will range from 45-55 degrees, with lows in the
upper 30s/low to mid 40s tonight, with the exception of the higher
elevations where lows will near freezing.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
The coastal low starts heading farther off the coast during the
day Saturday and Saturday night, but the upper trough nearby
and continuing northeasterly flow likely keeps a few showers
around at least on Saturday, probably abating Saturday night.
Saturday will also remain breezy and chilly under mostly cloudy
skies. Afternoon highs will be in the 40s with overnight lows in
the mid to upper 30s with the Poconos cooling to the low 30s.
Additional rainfall around one- quarter inch or less.

By Sunday, the system should finally pull far enough away to the
north and east to bring mainly dry conditions with even some partial
sunshine possible by afternoon...especially over eastern PA.
Temperatures will also rebound with highs getting back up into the
middle to upper 50s for most with overnight lows in the mid 30s
to low 40s.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
Monday may be the nicest day of the long term with high
pressure in place and westerly downsloping winds. Highs will be
in the 60s for most of us, possibly touching 70 across the
Delmarva.

A series of cold fronts will cross the region Tuesday into
Wednesday. At the moment, we have the first front moving through
Tuesday morning and the second one sometime during the day on
Wednesday. It doesn`t appear there will be a significant change in
airmass behind the first cold front, so high temperatures on Tuesday
will still be in the 60s for most of us. We`ll hold the far
northwest zones in the 50s. Rainfall chances hold in the 20-30%
range.

Cooler air will push into the region behind the second drier
cold front on Wednesday. Highs will get knocked down into the
50s for most, with some 40s in the Poconos. For Wednesday night,
we may have frost/freeze concerns with lows possibly dipping
into the 30s. And by this point, the majority of the forecast
area, sans LV/Poconos/NW NJ, will be frost/freeze active. No
precipitation is expected on Wednesday.

Thursday looks to be precipitation free as well with moderating
temperatures (but only slightly) spurred on by some mid-level zonal
flow.

&&

.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY and surrounding areas.

Today...Mix of MVFR/IFR to start, but expecting all sites to
come down to IFR by 13z or so.  Rainfall picks up in intensity
as the day goes on, reducing visibility down to 3-5 SM at times.
Easterly winds expected through the morning hours around 10 kt.
Wind gusts 20-25 kt out of the east pick up late this morning,
continuing through the rest of the day. Low confidence.

Tonight...Prevailing IFR likely with low clouds and 2-4 SM
visibility. Rain moves through the area overnight. Conditions could
go down to LIFR at times as well, but probability of that occurring
is low, only around 20%-25%. Northeasterly winds 10-15 kt and gusts
20-25 kt. Moderate confidence in prevailing IFR. Low confidence.

Saturday...IFR/MVFR in rain and low clouds to start the day.
Some improvement is possible late. Northeast wind 10-15 kt
gusting around 20 kt. Low confidence.

Outlook...

Saturday Night...sub-VFR at times as some rain showers and low
clouds linger.

Sunday through Tuesday...Mainly VFR. A few passing showers and
increased cloud cover possible Monday night into Tuesday.

&&

.MARINE...
For today, a Small Craft Advisory is in effect for all marine
zones as wind gusts out of the east will be around 25-30 kt and
seas 4 to 6 feet.

For coastal waters north of Little Egg Inlet, a Gale Warning is in
effect tonight through Saturday as wind gusts will increase further
to 35 kt. Otherwise for tonight, the Small Craft Advisory remains in
place for the remaining marine zones as gusts will be a bit lower,
around 30 kt. Seas will continue to build overnight, getting to 7-10
feet.

Outlook...

Saturday...Gale Warning across the northern coastal waters in
the morning, subsiding to small craft conditions by late
afternoon. SCA for all other marine zones. Seas 8 to 10 feet.

Saturday night...Small craft conditions expected to persist with
gusts near 25 knots and seas remaining elevated at 5 to 7 feet.

Sunday and Sunday night...Winds and seas will continue to
diminish Sunday. There still could be some residual SCA
conditions in play during the day and into the evening hours.
Sub- SCA conditions are expected overnight.

Monday...Sub-SCA conditions are expected Monday and most of
Monday night.

Tuesday...Sub-SCA conditions forecasted, though winds may gust
to around 20 kts.

&&

.TIDES/COASTAL FLOODING...
Spotty minor coastal flooding possible during the Saturday
evening high tide. A full moon tide along with persistent
northeasterly winds could result in minor inundation along the
coastlines of New Jersey and Delaware.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...None.
NJ...None.
DE...None.
MD...None.
MARINE...Small Craft Advisory until 6 PM EDT Saturday for ANZ430-431-
     452>455.
     Small Craft Advisory until 6 PM EDT this evening for ANZ450-
     451.
     Gale Warning from 6 PM this evening to 6 PM EDT Saturday for
     ANZ450-451.

&&

$$

SYNOPSIS...Kruzdlo/MJL
NEAR TERM...Hoeflich/Johnson
SHORT TERM...Fitzsimmons/MJL
LONG TERM...Kruzdlo/MJL
AVIATION...Hoeflich/MJL
MARINE...Hoeflich/MJL
TIDES/COASTAL FLOODING...