Delmar, Delaware 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

238
FXUS61 KPHI 131509
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
Issued by National Weather Service New York NY
1109 AM EDT Tue May 13 2025

.SYNOPSIS...
An area of low pressure enters the region for the middle of the
week and brings unsettled weather to the area. A series of cold
fronts move through on Friday and Saturday, keeping wet weather
in the forecast.

&&

.NEAR TERM /THROUGH TONIGHT/...
Light rain continues to move into the region from the south,
and showers will become steadier and more persistent throughout
the day. No significant changes are needed to the forecast.

Otherwise, a closed H5 low near the Gulf Coast states will lift
to the north towards the Ohio Valley later today, then backs
into the Great Lakes tonight. Several waves of surface low
pressure will spin off of this upper low and will lift north
along the East Coast first, this afternoon, then again late
tonight.

Wet weather will be in place as several waves of showers will
lift through the region. With increasing onshore flow,
temperatures will be on the cooler side today with highs in the
60s to around 70. Lows tonight will be in the 50s to low 60s.

Some unstable air will lift north into southern portions of the
area, mainly south of Philadelphia, and a few thunderstorms
will be possible across Delmarva and southern New Jersey
tonight.

Overall, 1/4 to 1/2 inch QPF will fall across northern New
Jersey, while 1/2 to 1 inch will fall across the rest of the
area, while up to 1 1/2 inches is possible over western suburbs
of Philadelphia today and tonight.

&&

.SHORT TERM /WEDNESDAY/...
A closed low continues to approach the region on Wednesday from
the southwest bringing an unsettled batch of weather for
midweek. Scattered showers move across the area Wednesday with
some isolated thunderstorms possible. For the thunderstorms,
there is a marginal risk of severe weather for a large portion
of Delmarva which is supported by the warm and humid air mass
that will be in place which will allow instability to climb
during the day. There is also some shear present as well.
Primary concern for any isolated severe thunderstorms would be
damaging wind gusts. The environment for any severe weather
becomes less favorable as you progress northward out of
Delmarva.

The coverage of showers starts to decrease Wednesday night as
they become more isolated and a rumble of thunder still cannot
be ruled out. This isolated coverage continues for Thursday
morning before becoming more scattered Thursday afternoon and
evening. We trend drier for Thursday night with a weak surface
high passing through.

As for temperatures, clouds and rain will keep the area cooler
on Wednesday with highs in the 60s and 70s. By Thursday, we are
a bit warmer with highs in the 70s for most. Lows both nights
will be in the 50s and 60s.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
The brief lull in unsettled weather continues Friday morning,
as an upper-level ridge builds in with a weak surface high
pressure system still passing through. This will allow drier
conditions but does not do much in the way of cloud cover. The
high pressure system does not last long as more showers and even
some thunderstorms arrive for the second half of Friday. A low
pressure system near the Great Lakes will lead to another active
stretch of weather for the end of the week and into the
weekend.

For Friday, there is a signal there for a cold front to move
through later in the day which could lead to more of a focal
point for showers and any thunderstorm potential. Another cold
front arrives later Saturday, which could have a similar
scenario as Friday by leading to a more focused area of showers
and thunderstorms. There is the potential for a severe weather
risk with the cold fronts on Friday and Saturday but there is
still uncertainty given this being in the long term part of the
forecast period. By Sunday, there is still a slight chance for
some showers to end the weekend and by Monday we trend drier
overall with a shower possible in the afternoon.

&&

.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Today...CIGs/VSBYs will lower to MVFR trough 18Z, and then CIGs
will lower to IFR by 21-00Z. Visibility mainly VFR to MVFR,
though VSBYs may dip to IFR from time to time in SHRA will be on
tap for the rest of the day. E-SE winds 5 to 10 kt, increasing
to around 10 to 15 kt with gusts up to 20 kt later today.
Moderate confidence overall.

Tonight...IFR CIGs and MVFR/IFR VBSYs in SHRA/BR. Isolated TSRA
possible at KPHL, KILG, KMIV, KACY. SE winds 10 to 15 kt with
20 to 25 kt gusts. Moderate confidence.

Outlook...

Sub-VFR with intervals of IFR likely through Thursday with
showers and a few thunderstorms. Conditions should improve a bit
Friday and Saturday with lower chances for showers and still
some thunderstorms possible.

&&

.MARINE...
East to southeast winds 10 to 15 kt will increase to 15 to 20
kt with 25 to 30 kt gusts from south to north later today and
tonight. Seas will build to 4 to 6 feet over northern NJ ocean
waters and to 6 to 8 feet over southern NJ and DE ocean waters
as well. Small Craft Advisories go into effect later today and
continue through tonight. VSBY restrictions in showers and fog
today and tonight. Isolated thunderstorms possible tonight.

Outlook...

Winds likely drop below SCA levels by Wednesday evening, but
SCA wave thresholds of 5 feet may persist on the ocean waters
until during the day on Thursday. Showers and spotty
thunderstorms will also be a concern on the waters through this
entire period.

Sub-SCA conditions should then take hold by Thursday evening
and continue through Saturday. However, showers and spotty
thunderstorms may continue to be a risk through Saturday,
especially during the afternoon and evening hours.

&&

.TIDES/COASTAL FLOODING...
No significant changes to the tidal and coastal flooding
forecast. Prolonged southeasterly flow will lead to an increase
in surge values as the week progresses, especially for the upper
Delaware Bay and tidal Delaware River. Surge values are
forecast to peak as much as 1-2 feet above normal. As a result,
minor coastal flooding is forecast with the overnight high tide
cycles beginning Tuesday night and continuing through at least
Wednesday or Thursday night.

A Coastal Flood Advisory was issued to highlight the threat of
minor coastal flooding for these areas. Additional advisories or
extensions may be needed in future updates.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...Coastal Flood Advisory from 1 AM to 6 AM EDT Wednesday for
     PAZ070-071-106.
NJ...Coastal Flood Advisory from 10 PM this evening to 2 AM EDT
     Wednesday for NJZ016.
     Coastal Flood Advisory from 1 AM to 6 AM EDT Wednesday for
     NJZ017>019.
DE...Coastal Flood Advisory from 10 PM this evening to 2 AM EDT
     Wednesday for DEZ001.
MD...None.
MARINE...Small Craft Advisory from 5 PM this afternoon to 11 AM EDT
     Wednesday for ANZ430-431.
     Small Craft Advisory from midnight tonight to 6 PM EDT
     Wednesday for ANZ450.
     Small Craft Advisory from 5 PM this afternoon to 6 PM EDT
     Wednesday for ANZ451>455.

&&

$$

SYNOPSIS...Guzzo/RCM
NEAR TERM...MPS/Staarmann
SHORT TERM...Guzzo
LONG TERM...Guzzo
AVIATION...Guzzo/MPS/Staarmann
MARINE...Guzzo/MPS
TIDES/COASTAL FLOODING...Cooper/Staarmann