Big Boulder

000
FXUS61 KPHI 312319
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
719 PM EDT Sat Oct 31 2026

.WHAT HAS CHANGED...
Updated Aviation section for the 00Z TAFs. 

&&

.KEY MESSAGES...
1. Some areas of frost tonight. Otherwise, generally tranquil 
weather is expected to prevail through the middle portion of 
next week.

2. Rain is expected to return late next week.

&&

.DISCUSSION...
KEY MESSAGE 1...Some areas of frost tonight. Otherwise, 
generally tranquil weather is expected to prevail through the 
middle portion of next week.

High pressure will remain in place within the vicinity of our area 
through the middle of next week with continuing mild and dry 
conditions. 

Temperatures are cooler today compared to yesterday and with the 
high building in right over our area for tonight, this will lead to 
very good radiational cooling conditions. Temperatures should fall 
quickly during the evening into the upper 30s and low 40s as winds 
decouple with the high pressure center nearby, then continue slowly 
falling overnight. A Frost Advisory remains in effect for portions 
of SE PA (not including Philly and Delco) into southern NJ where the 
growing season remains active with overnight lows in these areas 
generally in the mid 30s. North of these areas generally expect lows 
getting down into the low 30s while Delmarva and the urban corridor 
from around Wilmington through Philly will generally see lows in the 
upper 30s to around 40. 

For Sunday, we'll have a bit more in the way of some high cloudiness 
around but the winds will remain light and temperatures will 
moderate a few degrees compared to today. 

Scattered to broken high cloud cover will persist into next week 
despite surface high pressure. Temperatures are expected to increase 
back to above normal values early next week, with highs in the mid 
60s to low 70s and milder overnights (no frost/freeze potential). 
Dry weather is expected to persist through the day Wednesday.

KEY MESSAGE 2...Rain is expected to return late next week. 

The stretch of dry weather is expected to come to an end late next 
week. It appears increasingly likely that a period or periods of 
rainfall will move into the area as a storm system affects the 
region Thursday through at least Friday. Early in the week, a cold 
front will be moving across the central part of the country. The 
parent low moves across the Great Lakes and into Canada later in the 
week, while a secondary low develops and moves into the southern 
states by mid week. This low is expected to strengthen as it moves 
into the Mid Atlantic and northeast states later in the week, 
bringing our area a likely window to end our dry streak. Forecast 
details remain uncertain since this is still almost a week away but 
at this point the best chances for rain appear to be late day 
Thursday into the day Friday. At this time, this appears it will be 
a beneficial rainfall event with no significant weather hazards 
anticipated but it will have to be watched closely as the 
possibility is there for amounts to be on the heavier side depending 
on how much Atlantic moisture is pulled into the system.

&&

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

Tonight...VFR. N winds 5 kt or less to LGT/VRB. SKC. High
confidence.

Sunday...VFR. N-NE winds 5 kt or less to LGT/VRB, becoming S 5
kt or less late. High confidence.

Sunday night...VFR. S-SW winds less than 5 kt. High confidence.

Outlook...

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

Thursday...Next chance for rain arrives with the potential for sub 
VFR conditions.

&&

.MARINE...
Northerly winds around 10-15 knots early this afternoon diminishing 
to around 5-10 knots for the evening and overnight tonight. Winds 
around 5 knots or less for Sunday. Generally expect seas around 2 
feet through Sunday.

Outlook...

Monday through Tuesday...No marine hazards expected. Fair weather.

Wednesday through Thursday...Winds and seas may build close to 
advisory levels Wednesday night into Thursday.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...Frost Advisory from midnight tonight to 8 AM EDT Sunday for 
     PAZ102-104-106.
NJ...Frost Advisory from midnight tonight to 8 AM EDT Sunday for 
     NJZ016>018-021-023.
DE...None.
MD...None.
MARINE...None.

&&

$$

DISCUSSION...Fitzsimmons/Staarmann
AVIATION...Fitzsimmons/MPS/Staarmann
MARINE...Fitzsimmons/Staarmann