Claymont, Delaware 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

480
FXUS61 KPHI 272334
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
734 PM EDT Sun Jul 27 2025

.SYNOPSIS...
A weak front will cross the area late this afternoon and into
the evening. It will be followed by high pressure for the early
part of the upcoming week. A cold front arrives during the
midweek period. More high pressure should be across the region
for late next week and into next weekend.

&&

.NEAR TERM /THROUGH MONDAY/...
Tonight, the cold front will cross the area this evening and
overnight. Abundant low level moisture and heating (especially S/E)
will create showers/tstms into the evening period. High chance/low
likely pops in many areas to cover this. Downpours and gusty winds
with a small possibility for severe weather will continue with tstms.
Overnight, the precip will diminish and fog will develop overnight.
Not confident of dense fog attm, so we`ll broad brush the patchy for
in the grids attm. Humid and muggy overnight with lows in the 70s.
Light West to Northwest winds.

For Monday, the front will have crossed the area and high pressure
from the Ohio Valley will begin to build in. Upper heights will be
increasing too, so fair weather and hot temperatures are expected.
Dew points will still be uncomfortable (in the low 70s) but a little
less than the past few days (when we had mid/upper 70s). For this
reason, heat index values mostly settle in the upper 90s and low
100`s for Delmarva. These numbers are just a few degrees short
of Heat Advisory criteria. We`ll hold on any heat headlines for
now with the idea being that even lower dew points are possible.
Winds will be North to Northwest during the day at around 10mph.
At the shore, a sea- breeze is expected for the afternoon.

&&

.SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/...
The short term period as a whole will feature mostly dry conditions
under mostly sunny/partly cloudy skies as broad high pressure builds
into the region from the south. Perhaps a stray shower or storm is
possible on Tuesday, with more in the way of isolated storms and
increasing clouds on Wednesday ahead of a cold front.

The more notable part of the mid-week period will be another round
of potentially dangerous heat and humidity setting up across the
area. High temperatures on both Tuesday and Wednesday are forecast
to be in the mid to upper 90s with dew points in the low to mid 70s
both days. This will result in heat indicies around 100-105+ degrees
across most of the area; where Wednesday now looks to be the warmest
day. Likely will need some sort of heat headlines on Tuesday and
Wednesday in the coming days.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
The most notable change to the long term period is with regards to
the timing of the arrival of the strong cold front that will be
tracking through the region. Latest guidance further delays this
arrival, with the front now moving into the area late Wednesday
night into Thursday. As stated above, much of the day Wednesday now
looks quite dry, with increasing chances for showers and storms
beginning Wednesday night and continuing through Thursday. Still,
much of the machine learning guidance hints at the potential for
severe weather for both Wednesday night and Thursday, however the
extent of this is uncertain. If the front moves in at night, this
will likely hinder the extent of severe weather potential compared
to maximizing diurnal heating during the day. Will need to continue
to monitor this trend and potential in the coming days. Regardless,
this does look like the next opportunity to bring some widespread
rain and storms to the area. Also, PWATs are expected to be in
excess of 2", which may exacerbate the flash flood risk especially
if any training occurs. Due to this, WPC has portions of the region
in a MARGINAL risk of excessive rainfall on Wednesday with a
MARGINAL and SLIGHT risk of excessive rainfall on Thursday.

By Friday, depending on the forward progression of the front, there
will likely be some lingering shower activity around through Friday,
especially across the Delmarva. Fortunately, by the time the weekend
rolls around, we should see some drastic improvements across the
area with strong high pressure building over the Great Lakes. This
will result in dry conditions with temperatures expected to be as
much as 5-10 degrees below average over the weekend.

&&

.AVIATION /00Z MONDAY THROUGH FRIDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY and surrounding areas.

Tonight... Scattered showers will linger across the area into
the evening with lower chances across KRDG/KABE. Lower
conditions in rains/thunder but after 02z conditions will
improve back to VFR. Mist/patchy fog expected overnight with
some MVFR vsbys forecast in the terminals. Lower conditions
possible but high uncertainty. Low confidence.

Monday... Early morning mist/fog then VFR with sunny skies
expected. North winds 5 to 10 knots becoming West during the
afternoon. High confid.

Outlook...

Monday night through Wednesday...VFR. No significant weather
expected.

Wednesday night through Friday...Sub-VFR conditions probable with
showers likely. A chance for showers and thunderstorms possible in
each afternoon and evening.

&&

.MARINE...
South winds this afternoon will turn more Southwest by evening.
Overnight, winds continue to veer as a front crosses the waters. By
Monday morning, winds will be more North or Northeast. Speeds will
be around 10 to 15 knots on the ocean into the evening then less
than 10 knots overnight and much of Monday. Sub-SCA expected.

Scattered showers/tstms into the evening with locally higher winds
and seas. SMWs are possible especially for Delaware Coastal waters
and into Delaware Bay.

Outlook...

Monday night through Thursday...No marine headlines expected. Winds
will largely remain below 20 kt with seas around 2 feet or less.
Fair weather expected through Wednesday with showers and
thunderstorms for Wednesday night into Thursday.

Thursday night through Friday...SCA conditions probable due to winds
around 25 kt and seas building to 3-5 feet. Showers and
thunderstorms possible.

Rip Currents...

For Monday, winds start northerly and then turn easterly around
5 to 10 MPH. Breakers will be around 1 foot. Period will be 4
to 8 seconds. As a result, a LOW risk for rip currents is in
place at all beaches.

For Tuesday, winds turn southwesterly around 5 to 10 MPH.
Breakers will remain around 1 foot. Period will remain 4 to 8
seconds. As a result, a LOW risk for rip currents is in place at
all beaches.

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

&&

.CLIMATE...
Several days of high heat will commence Monday and continue
through Wednesday. Here`s a rundown of record warm high and
low temperatures.

Record warm high temperatures
Site                Monday 7/28  Tuesday 7/29  Wednesday 7/30
AC Marina (55N)      96 in 1999   96 in 2002    99 in 2002
AC Airport (ACY)     98 in 1999   98 in 2002    96 in 2002
Allentown (ABE)      97 in 1949   96 in 1954    97 in 1940
Georgetown (GED)     99 in 1949   99 in 2011    99 in 1949
Mount Pocono (MPO)   93 in 1949   90 in 1949    90 in 1954
Philadelphia (PHL)  100 in 1941   98 in 2002    98 in 1988
Reading (RDG)        99 in 1941   97 in 2002    97 in 1940
Trenton (TTN)        98 in 1940  100 in 1894    98 in 1999
Wilmington (ILG)    101 in 1894   99 in 1896    97 in 1954

Record warm low temperatures
Site                Monday 7/28  Tuesday 7/29  Wednesday 7/30
AC Marina (55N)      78 in 2020   78 in 2020    79 in 2020
AC Airport (ACY)     80 in 2020   78 in 2002    76 in 2015
Allentown (ABE)      75 in 1934   75 in 2002    74 in 2024
Georgetown (GED)     76 in 2022   78 in 2011    78 in 2009
Mount Pocono (MPO)   69 in 1955   71 in 2002    68 in 1909
Philadelphia (PHL)   79 in 2020   81 in 1995    80 in 2002
Reading (RDG)        78 in 1949   78 in 1949    75 in 1933
Trenton (TTN)        78 in 1894   80 in 1894    78 in 1894
Wilmington (ILG)     76 in 2020   82 in 1894    75 in 2019

&&

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

&&

$$

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