Area Forecast Discussion
Issued by NWS State College, PA
FXUS61 KCTP 240943
Area Forecast Discussion
National Weather Service State College PA
543 AM EDT TUE MAY 24 2016
Upper level low pressure centered over Long Island today will
move off to the northeast on Wednesday. A noticeably warmer and
more summer-like pattern with showers and thunderstorms possible
each afternoon and evening is expected to last into the first
part of the holiday weekend. slightly cooler weather may arrive
for Memorial Day.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Upper low will slide up to Boston harbor today. The cooler air
aloft will still result in some instability showers this
afternoon. LI`s barely go negative - probably because all the
instability will be below 10kft. A cap about that high or even
lower should keep things suppressed. But, a few shra could pop
over the ridges - mainly in the SE third of the area - and drift
SSE. will hold POPs to 20s east of the Main Stem Susquehanna
River. Otherwise, the ridging starting to translate eastward will
keep the cu down over western PA. Maxes should get back to where
they were today and maybe add two degrees due to less clouds and
very slightly warmer 8H temps.
.SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/...
After any diurnal convection dwindles at or before sunset, the
rest of the night should be quiet. Some patchy fog is possible but
dewpoints fairly low/dry. Sinking motion is maximized on Wednesday
as the upper ridge is nearly overhead. It should be a good day to
make some vitamin D - especially south of I-80. Just a thin layer
of high clouds may strafe the north. We should add another 2-4F
onto the maxes from Tuesday. SREF mean pops start to climb
Wednesday night with convection sliding in from the west. clouds
increasing from the west Wed night will probably keep mins in the
55-60F range or 5-10F above normals.
.LONG TERM /THURSDAY THROUGH MONDAY/...
Extended guidance continues the idea the development of an eastern
ridge/western trough pattern, bringing the arrival of the first
extended period of summer-like temperatures and humidity.
By Thursday we will be embedded in a broad wsw flow aloft.
Slightly above normal PWATS support the idea that humidity will
become noticeable over most of the area for the first time this
warm season. It also means we will be susceptible to mainly
afternoon convection pretty much on a daily basis into the
weekend. The limiting factor will be the eventual sharpness of the
upper ridge and how warm we manage to get aloft. The GFS is very
aggressive poking the Bermuda ridge strongly up over the eastern
U.S. Saturday while the ECMWF is a little flatter. The NAEFS is
more in line with the GFS which hints that Saturday could be the
day with smallest convective chances. I don`t have anything more
than chance pops in the extended given the muddy nature of the
ridge and low confidence that it will be able to shield us from
upstream convection that will be embedded in the flow.
The highest confidence part of the forecast is for temperatures to
be above normal through the end of the month.
.AVIATION /10Z TUESDAY THROUGH SATURDAY/...
09Z TAFS sent.
Still a breeze in spots. No fog expected now that
we have some breeze.
Overall a nice spring day with VFR conditions. Perhaps
a shower across the far east.
Wed...No sig wx expected.
Thu-Sat...Isold pm tsra impacts possible.