Area Forecast Discussion
Issued by NWS State College, PA-- Remove Highlighting --
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FXUS61 KCTP 250552
Area Forecast Discussion
National Weather Service State College PA
152 AM EDT MON JUL 25 2016
A cold front will push southeast across Pennsylvania late Monday.
High pressure will return for mid week. It will remain warm
throughout the period.
.NEAR TERM /UNTIL 8 AM THIS MORNING/...
Low-level pooling of 70-75F sfc dewpoints across the Lower Susq
Valley, combined with numerous outflow boundaries from earlier
convection and the approach a a weak upper level disturbance, will
lead to a likelihood of showers in many locations over the next
several hour across the region along, and to the SE of Interstate
After this batch of showers slides east of Lebanon and Lancaster
counties around 08z...the region will see rainfree, but still warm
and muggy conditions under plenty of layered clouds.
Patchy fog will occur through sunrise where some brief clearing
occurs, especially in locations that had rain Sunday evening,
It will be a muggy night with dwpts in the mid 60s to lower 70s in
many locations. Min temps will range from he u60s across the mtns
of northern and western PA, to between 70 and 75 degrees across
the ridge and valley region of Central PA.
.SHORT TERM /8 AM THIS MORNING THROUGH 6 PM TUESDAY/...
Ens mean 8h temps support max temps today from the u80s across
the Allegheny Plateau, to the m90s across the Susq Valley. A swrly
flow ahead of approaching cold front will draw up some of the most
humid air we have seen this summer with dwpts in the low 70s ovr
much of the area. The combination of heat and humidity warrants
continuation of the heat advisory across the SE counties for the
warmest hours of the afternoon.
A weak cold front will provide enhanced convergence in an
increasingly unstable airmass leading to the threat for some
strong storms, especially in the afternoon when the SREF and GEFS
pump CAPEs up to between 1500-2000J with a not unimpressive LLJ
sliding into the forecast area.
Any rain today will be very welcome, but probably not enough to
put a dent in the widespread dry conditions we have been
experiencing for the last several weeks.
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
Big story in the extended fcst is the expected heat wave lasting
into early in the upcoming week, as the axis of the subtropical
ridge briefly shifts from the plains to the northeast conus.
Anomalous upper lvl ridging building over PA should bring hot and
mainly dry wx this weekend, as warm temps aloft suppress
Some modest cooling appears likely by Tue/Wed of next week behind
weak cold front. However, temps still likely to remain somewhat
abv normal within a generally zonal flow.
Midweek weather looks dry again, with just low pops for isolated
tstms. Fri looks to be the next higher chance for tstm impacts
areawide as another cool front progged to move through.
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
Just a few showers left across the southeast for another hour
03Z TAFS sent.
Otherwise most of the night will be dry with VFR conditions.
Perhaps some fog and haze just before sunrise.
More showers and storms will be possible on Monday, highest
chance for strong storms would be to the east, given timing
of the cold front.
High pressure returns for Tuesday and Wednesday.
TUE-WED...AM fog poss. Otherwise VFR.
THU-FRI...Mainly VFR. SCT PM SHRA/TSRA.
Record high for Harrisburg today is 99 degrees set in 1940.
Record high for Williamsport is 100 set in 1934.
Heat Advisory from 3 PM this afternoon to 8 PM EDT this
evening for PAZ027-028-035-036-056>059-063>066.
SHORT TERM...Fitzgerald/La Corte