132
FXUS61 KPHI 021301
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
801 AM EST Mon Nov 2 2026

.WHAT HAS CHANGED...
Increasing potential for fog tonight into Tuesday morning and
Tuesday night into Wednesday morning. Otherwise, no significant
changes to the forecast.

&&

.KEY MESSAGES...
1. Aside from potential for nocturnal fog development tonight
and Tuesday night, generally tranquil weather is expected to
prevail through the middle of the week.

2. Rain chances return late this week and into the weekend.

&&

.DISCUSSION...
KEY MESSAGE 1...Some areas of frost again overnight. Aside from
potential for nocturnal fog development tonight and Tuesday
night, generally tranquil weather is expected to prevail
through the middle of the week.

High pressure will remain in place within the vicinity of our
area through the middle of the week. Dry weather is expected to
continue through Wednesday amid warming temperatures each day.

Scattered to broken high cloud cover will persist through the
middle of the week despite surface high pressure. Temperatures
are expected to increase back to above normal values, warming
each day through Wednesday. Highs will be in the mid 60s today,
in the upper 60s to low 70s Tuesday, and in the low to mid 70s
Wednesday. Overnights will becoming increasingly milder (no
frost/freeze potential). Dry weather is expected to persist
through Wednesday.

There is potential for areas of fog development both tonight and
Tuesday night. Dewpoints will also be on the rise each day.
Given mostly clear skies, light winds, and long nights, we
anticipate some fog development across the area during the
overnight periods. The latest hi-res guidance suggests the
lower visibilities (and thus higher dense fog probabilities)
will be along and southeast of the I-95 corridor and across the
coastal plain. Confidence on any dense fog is low, but this is
something that will be monitored for future updates. Where fog
does develop, it will likely be slow to mix out after sunrise
Tuesday and Wednesday mornings. Light southerly flow will
promote dewpoint advection and the solar insolation is
relatively weak until closer to midday, which will limit mixing
earlier in the morning.


KEY MESSAGE 2...Rain chances return late this week and into
the weekend.

The ridging that will be in place across the area for the
majority of the upcoming week will finally begin to break down
by Wednesday night into Thursday as a potent upper trough over
central portions of the US closes off and lifts northeastward
into portions of the Great Lakes, southern portions of Ontario
and Quebec, and perhaps northern New England late this week. As
this occurs, broad troughing is expected to take shape across
the eastern tier of the US, and a few lobes of upper level
energy will likely pivot through the region Thursday and into
the weekend. At the surface, low pressure centered over the
Midwest is expected to track northeastward as it weakens into
Thursday. After this time, there is still considerable
uncertainty as to how this system will evolve to impact our
local area.

At least broad low pressure looks to approach the area Thursday
into Friday coincident with the period of greatest height falls
across the region. This is expected to bring rain chances back
to the region, potentially as early as Wednesday night, but more
likely Thursday into Friday. For right now, PoPs are in the
50-70% range for most of the area during this time period. With
a lack of stronger forcing and little to no instability, this
looks most likely to be just a beneficial wetting rain to the
region.

Heading into this weekend, ensemble guidance indicates negative
H5 anomalies and generally lowered surface pressure across the
region. This indicates that the pattern may remain a bit
unsettled through Saturday before drier and cooler air begins to
work into the region by Sunday.

&&

.AVIATION /13Z MONDAY THROUGH FRIDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Today...VFR. Southwest winds less than 5 kts to calm early,
increasing to 5-10 kts after 16Z. High confidence.

Tonight...VFR to start, then areas of fog are forecast to
develop after 06Z. MVFR to IFR visibility, and some LIFR
visibility is possible. South to southwest winds less than 5
kts to calm. Low confidence on fog details, but moderate
confidence in fog impacting most terminals.

Outlook...

Tuesday through Wednesday...VFR is expected to prevail. Areas of
fog possible Tuesday night, otherwise no significant weather.

Thursday through Friday...Rain will be possible at times with
restrictions possible.

&&

.MARINE...
No marine hazards through tonight. Winds settling out of the
south to southwest around 5-10 kts today into tonight. Seas 1-2
feet. Fair weather through tonight, however some patchy fog is
possible near the Atlantic coast and Delaware Bay overnight.

Outlook...

Tuesday through Wednesday night...No marine hazards currently
anticipated with winds below 25 kt and seas below 5 feet. Patchy
nearshore fog possible again Tuesday night.

Thursday through Friday...Advisory conditions possible with
southeast winds increasing to 10-15 kt with gusts approaching 25
kt and seas increasing to 3-5 feet. Visibility restrictions
possible at times in rain.

&&

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

&&

$$

DISCUSSION...Cooper/Staarmann
AVIATION...Staarmann
MARINE...Cooper/Staarmann