191
FXUS61 KCTP 211808
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
208 PM EDT Fri Aug 21 2026

.WHAT HAS CHANGED...
No significant changes.

&&

.KEY MESSAGES...
1) Trending seasonably cooler this weekend into early next week
with showery periods Saturday and Sunday

&&

.DISCUSSION...
KEY MESSAGE 1: Trending seasonably cooler this weekend into
early next week with showery periods Saturday and Sunday

Large scale trough amplification expected over the Great Lakes
region this weekend into early next week will spell a modest to
seasonable cooling trend with showery periods Saturday and
Sunday. The cyclonic flow may keep showers downwind of Lake Erie
into Monday. Daytime highs will be near to slightly below the
historical average for late August, making it feel more like mid
September especially Sunday into Monday. SPC trimmed the MRGL
back a bit to the west on Saturday, which should feature early
day clouds and a few showers spreading from SE to NW during the
day. Drier/less humid conditions are likely to prevail during
the first half of next week.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
VFR will rule until some fog starts to show up in the valleys of
the north-central counties. However, BFD may escape unharmed.
IPT holds the highest highest probability (60%) of dropping to
L/IFR in either or both fog and low clouds. Low clouds will also
start to flow up into the southern tier (JST/AOO/MDT/LNS) near
or even just before sunrise. SHRA may follow quickly after that.
Looks like UNV/IPT/BFD should stay dry until after 18Z. But,
they will also then be in the favorable air for SHRA/TSRA to
form nearby. Mixing should help the cigs rise into lower-VFR
(FL035) at most sites. Coverage of SHRA in the aftn/evening will
expand a bit, but most SHRA/TSRA will wait until a deep trough
digging over the Great Lakes will force at least one line of
storms across OH and into PA. GFS is faster than NAM with this
convection. But, a safe bet based on these deterministic models
and multi-model ensembles of all kinds is that between 21 and
00Z they will get into Warren Co and then move eastward.

The SHRA/TSRA should move east thru the night and be off to the
east by sunrise. The deepening upper low then drops over the
lower Great Lakes and Lower Ontario. The dryness of the airmass
will likely keep convection confined to NW PA, closer to the
upper cold pool and in vicinity of the moisture from LE. Monday
looks similar with decent flying weather most everywhere, but a
several showers will bug BFD and one or two perhaps dip toward
FIG/UNV.

Outlook...

Sun...Restrictions possible, mainly NW in SHRA. Improvement
elsewhere.

Mon-Wed...Patchy morning fog, otherwise mainly VFR conditions
return early next week.

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

WHAT HAS CHANGED...Steinbugl
KEY MESSAGES...Steinbugl
DISCUSSION...Steinbugl
AVIATION...Dangelo