Easton, Pennsylvania Weather Forecast Discussion

589
FXUS61 KPHI 190551
AFDPHI
Area Forecast Discussion
National Weather Service Mount Holly NJ
151 AM EDT Fri Sep 19 2025
.SYNOPSIS...
A weak area of high pressure will remain across the Middle
Atlantic region much of today. A cold front will push through
the region tonight. 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 TONIGHT/...
Latest surface analysis places weak high pressure over our
region, centered on the central Appalachians. A cold front is
pushing southward across the St. Lawrence River Valley along
the US/Canadian border, with a stronger high pressure following
behind it in southern Canada. Aloft, a broad trough is
positioned across much of eastern Canada into the northeastern
United States, with a weak ridge to our west across the western
Great Lakes and Ohio Valley.
Through tonight, the ridge aloft will actually build eastward
toward our region even as the surface cold front presses
southward into our area. Thus, there is very little risk for any
precipitation or even a whole lot of clouds with this surface
front which is pretty lacking for any upper-level support.
Therefore, with northwesterly winds prevailing, expect a mostly
sunny and warm day, though humidity will diminish a bit. Highs
generally in the 80s after any patchy early morning fog
dissipates (though that looks very patchy at this time).
Tonight, northerly winds continue as the surface front settles
south and the high to the north builds in somewhat, while the
ridge aloft also builds in. Thus, a dry night is on tap. Lows
40s in the Poconos and NW NJ, 50s I-95 corridor away from the
urban core, and 60s Delmarva, urban core and immediate NJ
shore.
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
A cold front will clear the region by Saturday morning. 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 /06Z FRIDAY THROUGH TUESDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.
Thru 12Z this morning... VFR conditions with mainly clear skies
expected. Patchy shallow fog possible across the coastal
plains, mainly around MIV/ACY, but guidance has moved away from
that as of late. Other sites less certain with drier air
arriving thru the afternoon. Overall high confid, but only
moderate confid in fog occurrence/placement.
Today...VFR expected after any early fog. Some fair weather
afternoon cu with SCT 035-045 bases possible. Northwest winds 10
knots or less in the afternoon. High confid.
Tonight...VFR with northwest winds shifting northeast overnight,
but remaining 10 kts or less. High confidence.
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 today. A cold front
will approach later today and while no significant weather is
expected with it, winds will switch to south as it approaches.
Seas will be around 2 ft today. 1 to 2 ft waves for Delaware
Bay. Winds shift northerly behind the front tonight, and may
gust near 25 kts late with seas building to 3-4 ft, but
confidence on SCA headlines is low at this time.
Outlook...
Saturday through Monday...Northerly winds could approach or
exceed 25 kt 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.
Rip Currents...
For today, a more southerly wind near 10 mph is forecast to
develop with an east-southeast swell around 8 seconds. Breaking
waves in the surf zone are forecast to be a little lower (around
2 feet) than Thursday, and therefore continued with a LOW risk
for the development of dangerous rip currents at all beaches.
For Saturday, a surge in northeasterly winds are forecast to
develop from north to south, with speeds increasing to 15-20
mph. A southeast swell is forecast to be on the weaker side
with wave heights 1-2 feet with a period of 5-7 seconds.
Building waves in the surf zone (2-4 feet) should be much more
dominant over the swell. As a result, went with a MODERATE risk
for the development of dangerous rip currents at the Jersey
Shore and LOW at the Delaware Beaches. If the stronger wind surge
and higher breaking waves arrive faster at the Delaware Beaches,
the rip risk will then increase.
For specific beach forecasts, visit weather.gov/beach/phi
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...None.
NJ...None.
DE...None.
MD...None.
MARINE...None.
&&
$$
SYNOPSIS...Cooper/RCM
NEAR TERM...RCM
SHORT TERM...Cooper
LONG TERM...Cooper
AVIATION...Cooper/RCM
MARINE...Cooper/Gorse/RCM

NWS PHI Office Area Forecast Discussion