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000
FXUS61 KPHI 051342
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
942 AM EDT Wed Aug 5 2020

.SYNOPSIS...
High pressure from the midwest will build east today as the
remnants of Isaias move north into eastern Canada. A warm front
will move toward the southern portions of the forecast area on
Thursday and remain stationary into the weekend. High pressure
will then reassert itself across much of the area into next
week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Forecast largely on track this morning as high pressure builds
in from the west. However, some energy associated with the
aforementioned trough could touch off a few isolated showers or
a thunderstorm in the southern areas this afternoon.
Temperatures are expected to max out in the low 80s north and
upper 80s south, which is near to slightly above normal for this
time of year.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
A southwesterly flow at mid-levels of the atmosphere produced
by the retreating trough will allow a warm front to approach
from the south. An impulse along this front could touch off a
few showers and thunderstorms mainly south and east of the I-95
corridor late Wednesday night and on Thursday. High temperatures
on Thursday will range from the low to mid 80s, around normal
for this time of year.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
Thursday night, surface high pressure will be located over New
York with the ridge axis extending west across Michigan. This
elongated west/east ridge axis is due to a fractured upper level
trough axis with the parent upper level low exiting the
Canadian Maritime Provinces with weak mid-level energy located
over eastern Ontario. As the remnant energy approaches from the
west Friday, weak surface cyclogenesis will occur near central
VA with the resultant surface low pressure heading out to sea
Saturday morning. Only weak DCVA will accompany the system
Friday, but PWATs remain around 1.75" though so another round of
precipitation appears likely.

Saturday into Sunday a slightly quieter period will take shape
as the mid-level wave exits the region. Behind the wave, weak
subsidence will move overhead with PWATs falling off to around
1.4". This will keep the weekend dry, for the most part. Expect
temperatures near to slightly above average for this time of
year with highs in the mid to upper 80s and lows in the upper
60s.

By Monday the chance of showers and thunderstorms will return to
the Delaware Valley as moisture rich air sweeps north. PWATs
Monday will approach 1.80", but the apparent lack of forcing has
allowed the forecast to be trended towards more of climo
perspective. Expect humid conditions Monday and Tuesday with
temperatures above normal.

&&

.AVIATION /14Z WEDNESDAY THROUGH SUNDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY and surrounding areas.

Today...VFR conditions expected, but a scattered shower or
thunderstorm is possible at the southern TAF sites. Winds mostly W
to SW at 5 to 10 knots.

Tonight...VFR conditions expected, except in patchy fog during
the early morning hours and perhaps a few rain showers late.
Mainly light and variable winds.

Thursday...Mainly VFR conditions, but showers and thunderstorms
could temporarily reduce vsby and ceiling to MVFR at times,
especially in the south. Light and variable winds except in any
thunderstorms.

Outlook...

Friday and Saturday...Mostly VFR. Scattered SHRA/TSRA possible
each afternoon/evening that would result in brief sub- VFR
conditions at a given terminal. Fog may develop during the
overnight. Winds east to northeast Friday and Saturday. LGT/VRB
at night. Moderate confidence.

Sunday... Winds out of the south with mostly dry and VFR
conditions. Moderate confidence.

&&

.MARINE...
Today...Lingering 5 foot seas in the early morning, then sub-SCA
conditions with SW winds around 10 kt. Ocnl gusts to 20 kt possible
in the afternoon.

Tonight and Thursday...Sub-advisory winds/seas expected, except in
any thunderstorms.

Outlook...

Thursday through Sunday...Sub-advisory winds/seas expected
through the period. Chances of showers/storms through the
period, especially in the afternoon/evening hours.

Rip Currents...

The rip current risk will likely remain elevated on Wednesday
with light winds out of the southwest. On Thursday wave heights
will continue to fall towards 2 feet with with light east winds.
This will allow for the rip current risk to be low.

&&

.HYDROLOGY...
Between 3 and 6 inches of rain, with localized amounts of 8 to 9
inches, have fallen across much of southeast Pennsylvania,
western New Jersey, and Delmarva. Flooding continues across
these areas. Please refer to any Flood Warnings for details.

&&

.TIDES/COASTAL FLOODING...
The threat for tidal flooding in association with Isaias has
come to an end across the area. The coastal flood advisory will
expire as scheduled at 6 am. Fresh water runoff will continue
today in tidal portions of the Delaware River, but additional
tidal flooding is unlikely.

&&

.EQUIPMENT...
The NOAA Weather Radio All-Hazards broadcast from Hibernia Park
Pennsylvania (Station WNG-704) remains off the air.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...None.
NJ...None.
DE...None.
MD...None.
MARINE...None.

&&

$$
Synopsis...Miketta
Near Term...MPS
Short Term...Miketta
Long Term...Haines
Aviation...Haines/Miketta
Marine...Haines/Miketta
Hydrology...WFO PHI
Tides/Coastal Flooding...WFO PHI
Equipment...WFO PHI