Elkins Park, Pennsylvania Weather Forecast Discussion

460
FXUS61 KPHI 181901
AFDPHI
Area Forecast Discussion
National Weather Service Mount Holly NJ
301 PM EDT Thu Sep 18 2025
.SYNOPSIS...
A weak area of high pressure will remain across the Middle
Atlantic region tonight and into Friday. A cold front will push
through the region Friday night. Strong high pressure will build
southeast into the region through the weekend. The high
pressure will weaken and shift slowly eastward through the first
half of next week, with moderating temperatures and a few
chances for rain.
&&
.NEAR TERM /THROUGH FRIDAY/...
Surface high pressure and ridging aloft have brought sunny skies
and pleasant temperatures to the Northern Middle Atlantic region
this afternoon. Temperatures inland have climbed into the low/mid
80s while 70s continue for Delmarva and SE NJ where clouds persisted
longer earlier today. Winds have been rather light from the N & NW.
For tonight, skies will remain clear with the fair pattern continuing.
We`ll probably have areas of fog across southern NJ and Delmarva
in areas that had more clouds today and plentiful rains
yesterday. Fog will be more patchy in other areas. The drier air
will continue to arrive from the N/NW and it may not fully make
it into the S/E areas before sunset. Lows will be in the upper
50s to low 60s most spots. Winds will be light.
Another good weather day is expected Friday. Plenty of sunshine
early the some clouds for the afternoon. It will be very warm
for the end of September with highs in the low/mid 80s across
the region. Areas near the shore and the southern Poconos will
have highs in the upper 70s. Winds will be light favoring the
South or Southwest.
&&
.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/...
The cold front that will entire our area on Friday will finish
pushing south and clear the region by Saturday morning. No
precipitation is expected with this frontal passage, but it will
bring cooler temperatures. Lows on Friday night are expected to be
in the upper 40s across the higher elevations of eastern PA and far
northern NJ, the mid-upper 50s across southeastern PA outside of the
urban corridor and NJ away from the coast, and near 60 for coastal
locations, the urban corridor, and the Delmarva.
With high pressure in control on Saturday, partly cloudy skies and
highs in the mid 70s are expected. As the high slides slowly
southeastward Saturday night and Sunday, the area will be positioned
between the high center to the northeast and a stationary boundary
across portions of the Mid-Atlantic. This will set the stage for a
period of onshore flow and some increase in cloud cover for Saturday
night and Sunday. A sprinkle or two cannot be ruled out across the
Delmarva or near the southeastern coast of NJ, however, this doesn`t
appear to warrant to inclusion of PoPs at this time given the
airmass in place will be fairly dry.
Low temperatures Saturday night will likely again be in the upper
40s across the higher elevations of eastern PA and far northern NJ,
and in the mid 50s to lower 60s elsewhere. Highs on Sunday are
expected to be in the low-mid 70s areawide. Lows Sunday night will
range from the low 50s across northern parts of the area to the
upper 50s along the coast, in the urban corridor, and the Delmarva.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
Weak upper-ridging will be in place across the area Monday into
Monday night, with surface high pressure maintaining strong
influence. Moisture will be on the increase however as southerly
flow returns to the area. Overall, it looks to be a nice day with
partly sunny skies and temperatures rising into the mid-upper 70s
areawide. Temperatures overnight should also be warmer, with upper
50s to lower 60s being common.
Beginning on Tuesday, the upper-pattern will become slightly more
unsettled. A shortwave axis should pass to the north of the forecast
area Tuesday into Tuesday night. While the best forcing should be
displaced to the north, this system could be enough to trigger
isolated showers and perhaps a storm or two. The highest chance
appears to be Tuesday afternoon and into the overnight hours. After
the passage of this shortwave, the pattern looks fairly
unremarkable, however still unsettled with perhaps a weak impulse or
two passing through Wednesday into Thursday. Therefore, slight
chance to low-end chance PoPs appear warranted (20-30%) both days. A
more notable upper-trough and accompanying surface low may begin to
approach the area from the west late Thursday and especially beyond.
Tuesday and Wednesday look fairly similar in terms of temperatures,
with highs in the low 80s and lows in the low 60s. Thursday
currently appears to be slightly cooler with increasing moisture and
cloud cover, with highs generally in the mid-upper 70s.
&&
.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.
thru sunset... Decreasing clouds for SE NJ and Delmarva. VFR
expected. Light NW to W winds.
Tonight... VFR conditions with mainly clear skies expected.
We`ll likely have some rural fog across Delmarva and south NJ
late tonight so we`ll include that in KMIV/KACY TAF sites. Other
sites less certain with drier air arriving thru the afternoon.
Overall high confid, but only moderate confid in fog occurrence/placement.
Friday... VFR expected after any early fog. Daytime Cu/Sc with SCT
to BKN 035-045 bases. Northwest winds around 10 knots by afternoon.
Medium/high confid.
Outlook...
Friday night through Saturday...VFR. No significant weather.
Saturday night through Sunday night...Restrictions are possible
depending on the extent of potential marine stratus.
Monday though Monday night...VFR. No significant weather.
Tuesday...Period of Sub-VFR conditions are possible in isolated
showers and storms, particularly during the afternoon hours.
&&
.MARINE...
Fair weather will continue on the waters tonight and Friday. Weak
high pressure the rest of today and tonight will keep winds rather
light favoring a NW direction. A cold front will approach Friday and
while no significant weather is expected with it, winds will switch
back around to South as it approaches. Seas will be mostly around 3
ft into tonight then closer to 2 ft Friday. 1 to 2 ft waves for
Delaware Bay.
Outlook...
Friday night through Monday...Northerly winds could approach or
exceed 25 kt Friday night into Saturday behind the cold front. In
addition, seas will likely become elevated, at times near or
exceeding 5 feet, Sunday through Monday. Therefore, an SCA will
likely be needed for at least part of this period.
Monday night through Tuesday...Conditions are expected to be below
SCA criteria with winds under 25 kt and seas under 5 feet.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...None.
NJ...None.
DE...None.
MD...None.
MARINE...None.
&&
$$
SYNOPSIS...Cooper
NEAR TERM...OHara
SHORT TERM...Cooper
LONG TERM...Cooper
AVIATION...Cooper/OHara
MARINE...Cooper/OHara

NWS PHI Office Area Forecast Discussion