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301
FXUS61 KCTP 111528
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
1128 AM EDT Tue Jun 11 2024

.SYNOPSIS...
A pocket of cool air in the mid levels of the atmosphere will
help to create plenty of clouds today with afternoon high
temperatures averaging 5 to 10 degrees below normal for the
date.

High pressure will build over Pennsylvania late today
through Wednesday.

As the high drifts east of the region, heat and humidity will
ramp up for Thursday and Friday, followed by a cold frontal
passage with scattered thunderstorms during the day Friday.

&&

.NEAR TERM /THROUGH TONIGHT/...
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Anomalously cold air in the 850-700 mb layer and shallow
moisture advecting SE from the Lower Glakes will help to
maintain plenty of clouds across the Northern and Western
portions of the CWA today. The clouds are generally stratocu
with bases 2500-3500 ft AGL.

Vertical mixing of dry air above the cloud deck near and to the
SE of the Allegheny Front will create some significant holes in
the mid-late afternoon, while bkn-ovc skies could persist for
much or all of the day near, and just to the east of the RT 219
corridor from the Laurel Highlands to the NW Mtns of PA.

High temps will be in the mid 60s - mid 70s today, once again
5-10 deg below climo.

High pressure will begin to build in Tonight, which will
bring clearing skies and light/variable wind under 4 kts.
Patchy, or even some larger areas of fog are possible across
primarily the Northern Mtns of PA, with overnight lows ranging
from the upper 40s northwest to mid 50s southeast. Air/water
delta Ts should be around 20 deg F.
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&&

.SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/...
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Wednesday will be a transition day between much below normal
temps to start the week and warmer weather for Thursday and
Friday. Variable amounts of mid and high clouds on Wed will
have only a minimal impact on the otherwise abundant sunshine
with highs ranging from the low to mid 70s over the Northern
Mtns to the low 80s throughout the Valleys of Central and
southern PA. These readings will be just a few deg F shy of
climo. Winds will be light from the west. PWAT values will start
out around 0.8 inch and will increase to around 1 inch Wed
afternoon, but it won`t feel humid given sfc dewpoints
remaining in the 40s and 50s.

We`re still expecting a warm up for the second half of the
week, with many locations seeing their warmest temps on
Thursday, except perhaps southeast PA seeing temps a few
degrees warmer on Fri. Temperatures on Friday will depend on the
timing of clouds and convection associated with an approaching
cold front. Over the past 24 hours, models have generally sped
up the arrival time and southward progression of the
aforementioned front, now bringing a chance of showers and
thunderstorms to the northern Alleghenies as early as Thursday
night, and then dropping south across central PA during the day
Fri with more numerous showers and thunderstorms.

Despite forecast high temps near 90 across southern zones Thu-
Fri, relatively low levels of humidity (dewpoints 55-65F) will
hold the heat index to just a couple deg above the air temp.
Thus not anticipating heat products at this time. However, the
+15-20 degree swing from temps well below normal early this
week to the warm weather late this week will be noteworthy.
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&&

.LONG TERM /SATURDAY THROUGH MONDAY/...
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Next weekend looks dry, as a northerly flow of drier air from
Canada is advected into our area. Any slight cool down on
Saturday will be short-lived, with warmer temperatures progged
to build back into the area Sunday into Monday. The risk for
excessive heat will increase into the middle of the upcoming
week as a large ridge builds over the eastern US.
-- End Changed Discussion --

&&

.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
12z update... The latest observed satellite trends plus model
guidance yields fairly high confidence (70-80%) that lower
clouds will hang tough through at least 15-18z across the
Allegheny Highland (KBFD and KJST) and ridge and valley region
(KAOO and KUNV) terminal sites. KBFD should see the lowest
conditions (IFR restrictions), while KJST, KAOO, and KUNV are
more in the fuel alternate-MVFR range.

We do expect some improvement during the midday and afternoon
hours, especially for KAOO and KUNV, with VFR likely returning
at these two sites early this afternoon. KBFD could well hang
on to restrictive ceilings (MVFR-fuel alternate) into this
evening. We could see patchy fog develop again after 04-06z,
with the highest potential (40-60%) for this at KBFD.

Farther east across the Susquehanna Valley terminal sites (KIPT,
KMDT, and KLNS), cloud cover should be thinner and with higher
ceiling bases, so confidence is high (80-90%) of prevailing
VFR.

NW surface winds 5-10 kt for most sites today, should diminish
to light speeds by/after sunset.

Outlook...

Wed-Thu...Predominantly VFR w/ no sig wx expected.

Fri...Restrictions possible if afternoon/evening CB/TSRA
develop.

&&

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

&&

$$

SYNOPSIS...Lambert/Colbert
NEAR TERM...Lambert/Colbert
SHORT TERM...Lambert/Colbert
LONG TERM...Martin/Evanego
AVIATION...Jurewicz/Bowen/Tyburski