526
FXUS61 KCTP 120939
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
539 AM EDT Wed Mar 12 2025

.SYNOPSIS...
* After a brief cool down on Wednesday, warmer temperatures will
  return late in the week and remain with us into the weekend.
* A strong low pressure system will bring gusty winds this
  weekend and a threat for severe weather on Sunday.

&&

.NEAR TERM /THROUGH TONIGHT/...
Temperatures today will be about 10-20 degrees colder than
Tuesday`s highs, as high pressure builds to the north of the
state. Winds will be light as they gradually veer from NE early
to E and then SE through the afternoon. Highs today will range
from the mid 40s in the northeast to near 60 degrees across the
southern tier. Lighter winds should limit the risk of wildfire
spread somewhat, but low relative humidity (25 to 35 pct) is
expected once again this afternoon.

Warm advection will ramp up late today ahead of a shortwave
crossing the Grt Lks. As a result, expect thickening clouds over
Northern PA, where a few light rain showers are possible in the
afternoon and evening. Model soundings indicate some wet
snowflakes could mix in along the NY border, but accumulation is
not expected. The shortwave should have passed north of the
region by late Wed night, ending the chance of precipitation.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY/...
Low amplitude upper level ridging should keep Central PA
weather dry Thursday and Friday. However, a low level easterly
flow associated with high pressure east of New England should
keep daytime temps a bit cooler than NBM guidance and could
result in patchy low clouds, especially Friday morning based on
the latest ensemble prob charts.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
A complex system is expected to impact central Pennsylvania
this weekend as low pressure moves across the central US into
the Great Lake region. Rain showers remain possible, mainly
across western Pennsylvania, on Saturday given westerly flow and
an initial slug of moisture. Model guidance has been persistent
that the best chances of precipitation will occur on Sunday;
however, timing compared to yesterday has trended slightly later
into the afternoon hours. The abundance of moisture, collocated
with the best forcing brings high confidence in rain
overspreading much of the area by the late morning/early
afternoon hours. Enhanced southerly flow will also bring a
second slug of moisture from the Chesapeake Bay to portions of
eastern Pennsylvania during the afternoon hours, allowing for
increased precipitation with PWAT values in recent guidance
lighting up towards the 1.00-1.50" range across the eastern half
of the area. Comparing model PWAT values to previous soundings
for IAD and PIT outline that PWAT values will approach maximum
values for March 16th ~12Z, if model guidance continues to hold.
This rainfall will be largely beneficial over long- term
drought areas of eastern Pennsylvania with no large- scale
flooding concerns at this time.

The slightly later arrival of the cold front will also
introduce severe potential across southeastern Pennsylvania,
where the aforementioned moist airmass, coupled with ample
forcing and strong deep-layer flow will provide some potential
for damaging winds across southeastern Pennsylvania. Given
timing of the cold frontal passage, this threat is mainly
confined to the Lower Susquehanna Valley as outlined on the
Storm Prediction Center`s D6 Severe Outlook.

Another facet of this complex system will be the non-
thunderstorm wind, with the threat for strong southerly winds
maximized on Sunday. A fairly tight pressure gradient sets up
across western Pennsylvania late Saturday, with enhanced winds
on the ridgetops of western Pennsylvania. Recent model guidance
has trended downward with wind gusts/strength of the gradient;
however, there remains slight model inconsistencies within this
Saturday-Sunday morning timeframe. Enhancement of wind gusts
appear more likely on Sunday, where enhancement of the 925mb
low-level jet ramps up across eastern Pennsylvania, bringing an
increased potential for strong winds. At this time, point-based
forecasts exceed Wind Advisory criteria; however, still quite a
bit of time to tighten up the wind forecast on Sunday before
headlines will need to be considered.

&&

.AVIATION /10Z WEDNESDAY THROUGH SUNDAY/...
Looking at mainly VFR conditions today, as a cold front moves
south of the area.

A weak low will track eastward toward western PA late today.
An area of warm advection with this system will bring a chance
(30 to 40 percent) of a rain shower to the far north (BFD).

A bit of snow could mix with the rain. Otherwise mid lvl clds
will prevail today with this weak low pressure system.

Given the east to southeast flow and the current guidance,
I added another group for lower conditions after Midnight.

Outlook...

Thu...Isold SHRA possible mainly wrn PA.

Fri...VFR/no sig wx.

Sat...SHRA, highest chances across W PA, restrictions possible.

Sun...Widespread SHRA, TSRA possible across SE PA. Restrictions
probable.

&&

.CLIMATE...
A record high temperature of 75 degrees was set at Williamsport PA
on Tuesday. This broke the old record of 71 degrees set in 1977.

Bradford tied their record temperature of 66 degrees on Tuesday.
The previous record high was also set in 1977.

Altoona tied their record temperature of 74 degrees on Tuesday.
The previous record high was also set back in 1977.

&&

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

&&

$$

SYNOPSIS...Banghoff/Colbert
NEAR TERM...Fitzgerald
SHORT TERM...Fitzgerald/Colbert
LONG TERM...Colbert/NPB
AVIATION...Martin
CLIMATE...Martin/Bowen