Seaford, Delaware 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

731
FXUS61 KPHI 040238
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
938 PM EST Mon Feb 3 2025

.SYNOPSIS...
A low will pass to our north late tonight dragging a weak cold
through on Tuesday. High pressure will build in on Tuesday, followed
by an approaching low pressure system later on Wednesday through
Thursday night which will bring a mixed bag of precipitation to the
region. High pressure looks to briefly return at the end of the week
before the next low potentially arrives for the back half of next
weekend.

&&

.NEAR TERM /THROUGH TUESDAY/...
935 PM...Temperatures have been running a bit cooler than
forecast over portions of NE PA so there were some minor
adjustments made to tonight`s temperatures in this area.
Otherwise, no major changes made with the mid evening update.
Previous Discussion follows below.

For tonight, high pressure will remain in control of the weather
with just (mostly) high clouds across the area overnight. Low
pressure well northeast (Canada) will have its attached cold front
cross our area late tonight and into Tuesday morning. We are not
expecting any precipitation to occur with the front, but just some
lower clouds for awhile. The colder air won`t seep in until late, so
mild overnight lows in the 40s are forecast overnight. Across north
NJ and the southern Poconos, as well as the Lehigh Valley, readings
tonight will be in the mid/upper 30s. Winds will be light tonight.

On Tuesday, a cold front will drop down from the north and cross the
area during the morning. Although the front is not expected to
produce any precipitation over our area, there will be some morning
cloudiness. Temperatures will still be mild for early February, but
not as mild as Monday was. Highs will range from the low/mid 50s for
the far south to the upper 30s/low 40s across the north. Metro
Philadelphia and the Delaware Valley will have highs in the upper
40s for the most part. Winds will turn NW during the increase to 10
to 15 mph with gusts around 25 mph at times.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/...
The short term period will start off dry on Tuesday night as a
strong area of Canadian high pressure (~1036 mb) shifts east over
the Great Lakes and builds over the Northeast/Mid-Atlantic region.
High pressure will settle nearby on Wednesday before moving off the
coast of New England by Wednesday night. Overall, anticipate mainly
dry conditions with increasing clouds for Tuesday night with lows in
the teens/20s and mostly cloudy to overcast skies on Wednesday with
highs in the 20s/30s.

For Wednesday night into Thursday, attention remains on the low
pressure system that is set to affect the area as low pressure
tracks out of the Midwest across the Mid-Atlantic and up into New
England. Guidance has continued to depict a slower onset of
precipitation, so it does appear likely that precipitation will hold
off until at the earliest late Wednesday afternoon or Wednesday
evening across the region. It is important to note with this
specific system, is there will be an antecedent high located to our
northeast on Wednesday night, so there should be sufficient amount
of cold air especially at low levels that would support a cold air
damming set-up. Point forecast soundings support this quite well as
a pronounced warm nose will surge northward through the overnight
hours into Thursday morning as low pressure approaches. This would
certainly lead to quite a mixed bag of precipitation across the
region including both sleet and freezing rain.

For now, general consensus is that most locations should start off
with a period of light snow as temperatures will be below/around
freezing early Wednesday evening. However, as the warm nose aloft
progresses northward overnight, a change over to sleet and freezing
rain is expected from south to north at the surface. By Thursday
morning, most places should be changing over to rain as surface
temperatures rise above freezing, with the exception the Pocono
Plateau and northern New Jersey which will hold onto wintry precip a
bit longer. By Thursday afternoon, temperatures should rise well
into the 40s/50s as a strong surge of warm air advection occurs, so
plain rain will be anticipated by then. The timing and specifics of
the changeover are less certain though, but greatest confidence with
the prolonged duration of wintry p-types lies over our northern
Pennsylvania and northern New Jersey counties.

In terms of amounts, the current forecast calls for 0.50-0.75" of
liquid QPF. Breaking this down into snow/sleet totals, anticipate
generally a C-1" for much of the region, with localized areas of 1-
2" across the Pocono Plateau and higher terrain of northern New
Jersey. The more concerning aspect to the forecast is with respect
to freezing rain totals...where up to 0.1-0.2" of ice accretion is
expected northwest of the I-95 corridor where surface cold air is
likely to persist longer. For the I-95 corridor itself, including
the northern portions of the Delmarva and the remainder of New
Jersey, anticipate up to 0.1" of ice. Negligible ice accretion is
expected over southern Delaware. Considering this, Winter Weather
headlines will likely be needed within the next 24-48 hours.

Low pressure and precipitation will exit the region late in the day
on Thursday into Thursday night. Some left over rain showers will be
possible especially near the coast but most of the area will begin
to dry out by then.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
Little changes were made to the long term forecast as our attention
was mainly focused on the system discussed in the short term period.
High pressure and dry conditions are expected to occur on Friday
into Friday night. By Saturday, another low pressure system will be
approaching the area from the west as an active weather pattern
persists across the Eastern CONUS. Another period of rain/snow
certainly looks possible over the weekend. Although, temperatures do
appear to be above freezing for much of the region, so would favor
rain over snow as the main precipitation type. Best chance for snow
would be found in the typical spots in the higher terrain areas.

&&

.AVIATION /03Z TUESDAY THROUGH SATURDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY and surrounding areas.

Tonight...VFR should continue overnight with high clouds expected.
Lighter winds at the sfc, mostly S or SW will contrast with 40
to 45 kts aloft (2000ft), so LLWS for all terminals in the
01Z/02Z thru 09-10Z period. Medium/high confid.

Tuesday...A period of high-end MVFR CIGS possible for KRDG/KABE
around dawn, then improvement with VFR at all sites for the
rest of the morning and afternoon. Gusty NW winds around 15G25
kts expected. High confid.

Outlook...

Tuesday night through Wednesday...VFR. No significant weather
expected. Slight chance of snow possible late on Wednesday.

Wednesday night through Thursday night...Sub-VFR conditions likely.
A mixed bag of precipitation expected as snow will change to sleet
to freezing rain to rain.

Friday through Friday night...VFR. No significant weather expected.

Saturday...Sub-VFR conditions probable. Periods of rain/snow likely.

&&

.MARINE...
High pressure across the waters weakens overnight while low pressure
passes well north of the area. A cold front attached to the low
passes across the waters Tuesday morning. Behind the front winds and
seas build and a SCA flag will be needed for Tue. Winds will gust to
around 25 kts and seas will be up to 5 ft at times. More marginal
SCA for Delaware Bay, but decided to go anyway with a favorable NW
flow down the bay. Fair tonight and Tuesday.

Outlook...

Tuesday night...SCA conditions possible as wind gusts may linger
around 25 kt early Tuesday night. Fair weather.

Wednesday through through Wednesday night...No marine headlines
expected. Rain/snow mix likely.

Thursday through Friday...SCA conditions probable due to wind gusts
up to 30 kt and seas around 5 feet. Periods of rain on Thursday.

Friday night through Saturday...No marine headlines expected.
Rain/snow mix on Saturday.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...None.
NJ...None.
DE...None.
MD...None.
MARINE...Small Craft Advisory from 10 AM to 6 PM EST Tuesday for ANZ430-
     431-453>455.
     Small Craft Advisory from 7 AM to 6 PM EST Tuesday for
     ANZ450>452.

&&

$$

SYNOPSIS...AKL/DeSilva
NEAR TERM...Fitzsimmons/OHara
SHORT TERM...DeSilva
LONG TERM...AKL/DeSilva
AVIATION...DeSilva/Fitzsimmons/OHara
MARINE...DeSilva/OHara