Long Neck, Delaware 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

197
FXUS61 KPHI 201850
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
150 PM EST Sat Dec 20 2025

.SYNOPSIS...
High pressure will move offshore the Delmarva coast later today.
A couple of dry cold fronts are expected to move across the area
Sunday and early Monday, followed briefly by high pressure later
Monday. A warm front and subsequent cold front is then forecast
to move across the area around Tuesday into early Wednesday,
followed briefly by high pressure late Wednesday. A pair of weak
disturbances could then affect the area for the end of next week.

&&

.NEAR TERM /THROUGH SUNDAY/...
Surface high pressure located over the Delmarva is in control this
afternoon. Mostly sunny skies are found across the area with light
winds and temperatures in the low 30s to low 40s. Overall, a
pleasant afternoon.

Tonight, high pressure will shift offshore and weak southerly return
flow will set-up across the Mid-Atlantic. Skies will be mostly clear
early, with an increase in high clouds after midnight as low
pressure tracks across southern Canada. Overnight temps will be a
bit warmer than last night as a result, with lows ranging from the
mid 20s to mid 30s.

For Sunday, low pressure continues to track east across Quebec as a
cold front trails to the southwest. This front will cross through
the area by mid to late morning. No precipitation is expected as the
front lacks any moisture. Behind the front, another cold air
advection regime will begin as winds shift from southwest to
northwest where winds may gust between 25-35 mph during the
afternoon. Despite cold air advection ramping up, temperatures are
expected to be notably warmer due to stronger diurnal mixing and
warmer temperatures to start the day. Thus, expect highs to top out
in the low 40s to low 50s (mid 30s in the Poconos).

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
High pressure building in from the west should allow for diminishing
winds and clearing skies Sunday night. Fresh cold advection will
push lows deep into the 20s, with teens in the Poconos.

High pressure will pass just to our south during the day Monday,
with relatively light winds becoming more westerly. This should
allow plenty of morning sun, but the next weak system approaches
from the northwest with increasing clouds later in the day. Highs
low 40s Delmarva/far S NJ, 30s most of the rest of the region.

Monday night into Tuesday are a bit tricky, but of the light
variety. Radiational cooling should bring temps in much of the
area back below freezing during the evening before clouds get too
thick.  Thereafter, a weak system, really not much more than a
clipper, will move into the region with warm advection Monday night.
Still some uncertainty about just how far south precip can break out
with the warm advection ahead of the system, but there does appear
to be at least a little Gulf moisture available, so its within the
realm that much of the area gets some light precip. Then the
question of how quickly it starts and how quickly the southerly flow
warms up surface temps comes into play. Right now, areas north of
Philly stand the naturally best chance of seeing precip and sub-
freezing temps coincide, which in this case likely means a period of
light snow. Further south, temps stand a better chance of warming
before any precip arrives, which would mean non-accumulating snow or
just rain. While amounts look light regardless, up to an inch or so
of snow can`t be ruled out early Tuesday, with best odds being
across the Poconos and far northern NJ. A small accumulation is in
the forecast down to Philly, but confidence is low. Given the high
volume of travel during this period in the leadup to Christmas, any
wintry weather can be problematic, though an advisory-level event
looks unlikely. In any case, as the system moves through during the
day Tuesday, the southerly flow prevails and it looks likely that
most of the area will reach the 40s, perhaps just high 30s Poconos,
but around 50 in the Delmarva, with any precip tapering off in the
afternoon.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
Clipper system heads off the coast Tuesday night, but the air mass
behind it is more Pacific than Canadian. Thus, lows will struggle to
drop back below freezing across the region. This failure to drop may
be assisted by winds and cloud cover remaining a bit elevated.

Some sun with a diminishing breeze will be had on Christmas Eve
(Wednesday) as high pressure builds into the region, with highs
again in the 40s for most, 30s Poconos.

This high slides overhead and then east Christmas Eve night
(Wednesday night), with another weak clipper-like system
approaching from the northwest. Confidence is much lower on this
system, but its not impossible some light precip accompanies it,
especially in northern areas, which could even be in the form of a
little snow if surface temps drop enough during the evening before
clouds arrive. Lows in the 20s to low 30s.

Better chance this weak clipper arrives during the day Thursday
(Christmas day), by which time temps should be solidly above
freezing and any precip would be rain. Confidence is still low
however. Temps remain similar to the prior two days, with highs
mainly in the 40s, 30s Poconos.

Initial system may depart by Thursday night (Christmas night) but
another weak wave could arrive in its wake, providing a continued
chance of some precip. Temps likely stay above freezing with the
southerly to southwesterly flow across the region by this point,
resulting in any precip likely just being rain.

Friday still looks pretty mild but uncertainty continues regarding
any precip with another impulse possibly crossing the region. Highs
still look like 50s for most of the region, possibly topping 60
Delmarva but only 40s for Poconos/NW NJ. This does look a little
lower than 24 hours ago.

By Saturday, guidance is much more uncertain regarding whether we`re
still mild or cooling off, or dry vs wet, as the speed and progress
of disturbances and fronts gets pretty uncertain by this point. GFS
shows strong high pressure sliding south, cooling us off
substantially, while EC still showed us south of the next cold
front, and GGEm shows a weak wave of low pressure overhead.
Therefore, kept temps a bit cooler than Friday, more similar to the
bulk of this coming week with 40s for most, with just a slight
chance of rain.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY and surrounding areas.

Rest of Today (through 23Z)...VFR with SCT high clouds. West winds
around 5-10 kt will settle out of the south-southwest late in the
day. High confidence.

Tonight...VFR. Mostly clear skies early with SCT/BKN high clouds
developing late. South-southhwest winds around 5-10 kt. LLWS
possible at all terminals developing between 01-05Z from west to
east. Moderate-high confidence.

Sunday...VFR with decreasing clouds. Southwest winds around 5-10 kt
veer to northwest around 10-15 kt with gusts up to 25 kt possible
behind cold frontal passage. Moderate-high confidence.

Outlook...

Sunday night through Monday...VFR.

Monday night and Tuesday...Sub-VFR possible with the chance of some
rain and snow.

Tuesday night through Wednesday...VFR likely.

Wednesday night through Thursday...Sub-VFR possible with a chance of
rain.

&&

.MARINE...
Small Craft Advisories for both the Atlantic Coastal waters and
Delaware Bay have been issued beginning at 10 PM tonight and
continuing through Sunday.

South-southwest winds around 10-15 kt will increase tonight to
around 15-25 kt with gusts up to 30 kt possible. Cold frontal
passage will occur around mid-day on Sunday where winds will
gradually veer to west-northwest with gusts up to 25-30 kt. Seas of
3-6 feet. Fair weather anticipated through Sunday outside of SCA
conditions.

Outlook...

Small Craft Advisory conditions continue Sunday night into Monday
morning before dwindling. Sub-SCA conditions then prevail rest of
Monday into Monday  night, but SCA conditions may redevelop late
Monday night and persist through Wednesday. There might even be
a period of gales on Tuesday into Tuesday night. Sub-SCA likely
prevails Wednesday night before SCA conditions possibly redevelop
Thursday.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...None.
NJ...None.
DE...None.
MD...None.
MARINE...Small Craft Advisory from 10 PM this evening to 3 AM EST
     Monday for ANZ430-431.
     Small Craft Advisory from 10 PM this evening to 6 AM EST
     Monday for ANZ450>455.

&&

$$

SYNOPSIS...RCM/Staarmann
NEAR TERM...DeSilva
SHORT TERM...RCM
LONG TERM...RCM
AVIATION...DeSilva/RCM
MARINE...DeSilva/RCM