Laurel, Delaware 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

143
FXUS61 KPHI 130133
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
933 PM EDT Wed Mar 12 2025

.SYNOPSIS...
The base of high pressure over eastern Canada will extend
through the Northeast and into the Mid-Atlantic through Friday.
A warm front lifts north through the region Saturday morning,
and then high pressure will be in control until a cold front
passes through the region Sunday night. High pressure returns
for the new work week.

&&

.NEAR TERM /THROUGH THURSDAY/...
Tonight, a subtle shortwave will pass across interior New
England. This may spark a few light rain/snow showers across the
higher terrain, mainly confined to north of the I-80 corridor.
Otherwise, surface high pressure over southern Quebec will shift
east into the Gulf of St. Lawrence with the base of the high
extending into the northern Mid-Atlantic into Thursday. A
stalled frontal boundary also remains draped over the southern
Delmarva which will remain put through Thursday.

With surface ridging becoming more established across the
region tonight, the marine layer will move inland quite easily.
As it does so, we should see marine stratus roll in later
tonight, especially after midnight. This will keep temperatures
at bay with most locales falling into the low 30s to low 40s by
early Thursday morning. Some patchy fog cannot be ruled out
along the coast and across the Delmarva as well where dew point
depressions are lower. For Thursday, little in the way of a
pattern change is expected. Persistent northeast flow will
continue with more of a marine influence compared to Wednesday.
This should result in temps being a few degrees cooler under
mostly cloudy skies, but still should remain in the upper 40s to
mid 50s. All in all, seasonable temps are in store for
Thursday.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
High pressure remains over eastern Canada through Friday, with
the base of the high down through the Northeast and Mid-
Atlantic. This will result in an east to northeast flow, that
will allow for a cool and humid airmass over the area. Some
patchy fog will develop Thursday night, and with some weak
shortwave energy passing through the Carolina coast, some light
rain may develop over the New Jersey and Delaware coasts.

Partly to mostly cloudy and cool, relative to temperatures this
week, but still a few degrees above the seasonal average, on
Friday. Highs top off in the mid and upper 50s, though much
cooler at the coasts due to onshore flow and ocean temperatures
in the 40s.

High pressure over eastern Canada lifts away and winds take on
more of a southeast flow. Low level moisture will increase over
the area, this may lead to patchy fog and drizzle across the
region with a slight chance for light rain east of the I-95
corridor.

A warm front will develop out from deepening low pressure over
the Upper Midwest and this will lift north through the region
Saturday morning. Southerly flow ushers warm air advection into
the region with temperatures will in the 60s to low 70s. As that
front approaches, some showers may develop in the late
afternoon over the far western zones.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
Strong low pressure lifts into Canada, and this drags a strong
cold front through the Great Lakes Saturday night, and will be
over the Ohio Valley down through the Gulf Coast states on
Sunday. A tight southerly pressure gradient will develop between
high pressure over the Atlantic Ocean and low pressure north of
the Great Lakes over the Northeast and Mid-Atlantic. Strong
winds aloft will be associated with this approaching system,
with a potential 50 to 60 kt low level jet that moves across the
region Sunday afternoon and evening, and then a 100+ kt jet
streak following behind Sunday night. During the day, south
winds will increase to 20 to 30 mph with 35 to 45 mph gusts. A
Wind Advisory may be needed.

It will be quite warm and humid on Sunday, at least by mid-
March standards. High temperatures will be in the 60s to low 70s
with surface dew points well in the 50s to low 60s. 12Z/12 GFS
has minimal surface-based CAPE, generally less than 100 J/kg,
and generally less than 200 J/kg of most unstable CAPE. 13Z/12
NBM Mean surface-based CAPE is also generally less than 200
J/kg. However, 12Z/12 GFS shows 65 to 75 kt of 0-6 km Bulk
Shear. So this will be a low-CAPE, high-shear event in which
thunderstorms could produce damaging wind gusts. This will be on
top of synoptic winds already gusting as high as 35 to 45 mph.

In addition, PWATs look to be in excess of 1.5 inches. Given
how dry it has been, not expecting widespread flash flooding,
but heavy rain and localized street flooding are possible Sunday
afternoon and night.

Cold front swings through Sunday night, and then a cooler and
much drier airmass spreads into the region Monday with highs
generally in the 50s. Again, compared to how warm it will be on
Sunday, these temperatures will feel much cooler, yet these
highs are still several degrees above the seasonal averages.
Surface dew points fall into the 30s. Most showers should be
over by Monday morning, but some showers may linger along the
coast into the afternoon.

High pressure builds east for the first half of the new work
week with dry conditions and temperatures warming back through
the 60s to around 70 by the middle of the week.

&&

.AVIATION /02Z THURSDAY THROUGH MONDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Tonight...Sub-VFR conditions with low stratus clouds causing
ceilings to drop around 5Z. KMIV has the potential for some
patchy fog as well causing lower visibility. For winds, they
become more easterly by 5Z and ENE by 10Z at 5-10 knots. High
confidence.

Thursday...Sub-VFR with continued low ceilings due to low
stratus clouds. Any patchy fog for KMIV looks to dissipate after
13Z. Winds are 5-10 knots out of the east-northeast. High
confidence.

Outlook...

Thursday night through Friday night...Sub-VFR in fog/low clouds
at night. VFR during the day.

Saturday...VFR.

Sunday...Sub-VFR conditions developing in the afternoon and
evening in SHRA with scattered TSRA. S winds 15 to 25 kt with 30
to 40 kt gusts, abruptly shifting W and diminishing at night.

Monday...Lingering SHRA possible, otherwise, VFR.

&&

.MARINE...
A Small Craft Advisory is in effect for all Atlantic coastal
waters through Thursday night.

East-northeast winds 13-18 kt tonight with periodic gusts up to
20-23 kt. These wind conditions will persist into Thursday.
Seas around 4-6 feet. Fair weather expected, although localized
marine fog is possible tonight into Thursday, especially south
of Cape May Point.

Outlook...

Thursday night...SCA conditions due to 5 ft seas. VSBY restrictions
in fog possible late, especially along the coasts.

Friday through Friday night...Sub-SCA conditions expected. VSBY
restrictions in fog and drizzle possible at night, especially along
the coasts.

Saturday...SCA conditions develop in the afternoon and continue
through the night. VSBY restrictions in fog possible in the morning,
especially along the coasts.

Sunday...Gale force winds likely. VSBY restrictions in showers and
scattered thunderstorms in the afternoon and at night. After the
gales end Sunday night, SCA conditions are likely.

Monday...SCA conditions possible.

&&

.FIRE WEATHER...
Fire weather concerns will dwindle on Thursday with an easterly
flow bringing higher humidity to the region.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...None.
NJ...None.
DE...None.
MD...None.
MARINE...Small Craft Advisory until 7 AM EDT Friday for ANZ450>455.

&&

$$

SYNOPSIS...MPS
NEAR TERM...DeSilva/RCM
SHORT TERM...MPS
LONG TERM...MPS
AVIATION...Guzzo/MPS
MARINE...DeSilva/MPS/RCM
FIRE WEATHER...PHI