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000
FXUS61 KPHI 240735
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
335 AM EDT Fri May 24 2019

.SYNOPSIS...
High pressure across the Great Lakes region will build across the
Middle Atlantic later today and remain across the region through
saturday. Low pressure will move north of the area Sunday and Monday
causing a front to move across the region. More high pressure will
return for later Monday and into Tuesday. A disturbance will arrive
for the middle of next week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Much quieter day in store for the area as surface high pressure
builds NW of the area over the Great Lakes while at mid lvls heights
rise as the SE ridge tries to build northward in the wake of the
earlier shortwave.

Given good mixing and modest pressure rises, will likely see breezy
northwest winds through most of the daytime hours (gusts generally
in the 20-30 mph range). There will be a considerably drier airmass
in place with cloud cover limited to patchy cirrus and some
stratocumulus (most notable over northern portions of the area).
Given a well-mixed atmosphere, a good amount of sun, and offshore
flow highs will generally run in the mid 70s to low 80s (probably a
bit cooler in the far north where there may be more cloud
cover).

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
The high will move overhead this evening and then offshore
overnight, which will cause the northwesterly winds to decrease in
speed and veer to a more easterly direction. Models indicate a weak
shortwave diving around the eastern side of the ridge overnight in
the vicinity of Delmarva, but am not expecting anything other than
maybe an increase in mid-clouds from this feature. Other than that
overnight mins should cool to near climo , given onshore flow,
lighter winds, and a drier airmass.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
The overall synoptic setup will continue with an upper high
pressure across the south and a rather deep trough over the
western part of the country. A low across Canada will guide low
pressure systems and fronts across the Great Lakes and Middle
Atlantic this weekend and into the middle of next week. This
means showery conditions with some tstms possible. The most
favored times for the rains are Sat night thru Sun night and
again Wed/Thu next week. Since the pattern is more showery, some
locally heavy rains are possible, but the rains will be scattered
and intermittent.

Temperatures will be near normal Saturday, but then turn much
more summer-like Sunday when mercury readings will approach 90
in many areas, save the Southern Poconos and the shore. The above
normal readings will carry into next week, although highs Mon/Tue
will be more like low/mid 80s. Highs will then go back into the
low 90s Wed and perhaps again Thu. Humidity levels will be
somewhat uncomfortable Sunday and then again towards the
middle of next week.

&&

.AVIATION /07Z FRIDAY THROUGH TUESDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY and surrounding areas.

Friday...VFR conditions are expected at all terminals. NW winds
sustained around 15 kts with gusts up to around 25 knots are
expected through mid-afternoon.

Friday night... VFR conditions are expected with winds decreasing in
speed to around 5-10 kts, and veering from Northerly to
Easterly and then eventually Southeasterly by Saturday morning.

Outlook...

Sat...Mostly VFR.

Sat night thru Sun night...VFR much of the time, but a few
   showers and tstms with lower conditions possible.

Mon thru Tue...Mostly VFR.

&&

.MARINE...
A small craft advisory remains in place for the Atlantic coastal
waters through 7 AM this morning. Seas will come down to 2-3 feet
this afternoon with northwesterly flow prevailing. Winds will likely
gust to 20-25kts at times this afternoon.

Sub-SCA conditions are expected Friday night.

Outlook...
Winds and seas will likely remain below SCA conditions for the
weekend and into early next week. Mostly fair weather is
expected, but a few tstms will be across the waters Sat night
and again Sunday night. Locally higher winds and seas are
possible with any tstm.

&&

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

&&

$$
Synopsis...O`Hara
Near Term...Carr
Short Term...Carr
Long Term...O`Hara
Aviation...Carr/O`Hara
Marine...Carr/O`Hara