Critical Fire Weather Conditions in the Plains; Increasing Severe Weather Chances for the Plains and Upper Midwest

A strengthening storm system will bring impactful weather to the much of Central U.S. over the next couple of days, including heavy snow in the northern Rockies, Critical fire weather conditions for portions of the Plains, and increasing severe weather chances from the central/southern Plains to the Upper Midwest. Read More >

Here is the latest Area Forecast Discussion for Central PA

This text statement is the latest forecast reasoning from the NWS in State College, PA

See the links at the bottom of the page for previous issuances/versions of the statement as well as our other text statements.

663
FXUS61 KCTP 221906
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
306 PM EDT Wed Apr 22 2026

.WHAT HAS CHANGED...
* Lowered today`s dewpoints by up to several degrees F.
* Potential for faster timing with the exit of the main batch of
showers Saturday morning/midday based on 12Z Model Consensus,
though would like to see 2 cycles in a row better supporting
this trend.

&&

.KEY MESSAGES...
1) Much warmer than recent days this afternoon and even warmer
Thursday and Friday. Numerous light showers this morning, many
more on Friday.

2) Wet start to the weekend.

&&

.DISCUSSION...
KEY MESSAGE 1: Much warmer than recent days this afternoon and even
warmer Thursday and Friday. Showers Friday into Sat morning.

A weak north/south sfc trough was pushing across Central PA this
mid afternoon.

Very limited within the low-mid level thermal trough
could touch off a few isolated/very brief rain showers from KUNV
to KELM and points east through 23Z.

The wind becomes light northerly this evening after the passage
of the trough.

For tonight clear to partly cloudy with patchy fog late, mainly
across the NW Mtns and portions of the mid and lower Susq
Valley.

Thursday looks dry and much warmer, jumping about 10F over
today. Everyone but the far NErn mtns will be in the 70s. An
80F is not out of the question close to the MD border. This
warmth and associated deep mixing should help dewpoints/RHs get
a little lower than NBM guidance. Min RH should be close to 30
pct if not lower Thurs. NAM is an outlier with much higher
dewpoints and cloud cover and slightly cooler temps in the west.
Have discounted for now. The front that passes through late
today/early tonight will return northward over western PA on
Friday.

------------------------------------

KEY MESSAGE 2: Wet start to the weekend.

The lift over the front and daytime instability will generate
sct SHRA/TSRA in the western half of the CWA on Friday. The
cold air tries to hang on over the east and may even back in a
bit as the upper low over New England presses southward along
the coast. This will keep the warm front in place or nudge it to
the west as a backdoor cold front.

The energy diving down from the N/NW and perhaps an enhanced
LLJet will bring in more moisture, and generate more SHRA/TSRA
Fri night. Sat looks pretty wet for everyone with numerous
SHRA/TSRA. QPF in the 0.5-1.00" range is a solid forecast for
many Fri night and Sat.

The bulk of the 12Z guidance has trended about 6 hours faster
and a bit drier for the precip Sat morning, but will wait to see
another model run before making significant changes to the
current running forecast for that 12 hour period (12Z Sat - 00Z
Sun).

Some model divergence is seen for Sunday, though. Confidence is
low in how fast the precip moves through. So, Sunday may hold
sct SHRA, and PoPs in the 20-35% range are being kept for the
time being.

Next storm system approaches for Tues, resulting in a medium
confidence and medium to high PoPs. Will leave those high PoPs
in for now, but model/EPS difference exists on evolution of the
storm/mass fields.

&&

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
Widespread VFR is for the about the first half of the 18Z TAF
cycle as W/NW winds at the SFC and aloft advect drier air over
the region. With that said, a few brief showers may develop near
a weak north/south trough as it pushes east across Central and
Eastern PA late this afternoon.

Prob 30 for -SHRA included at KIPT between 19Z-23Z based current
Sat/Radar trends and some high res model guidance.

Overnight (after 06Z), fog development becomes a concern due to
largely cloud-free skies and light winds, particularly across
the southeastern airfields (KMDT/KLNS) and near KBFD.

For KMDT/KLNS, light easterly flow on the backside of the low
pressure that brought us rain showers earlier today will keep
low-level moisture in place, increasing the chances for
visibility restrictions due to mist/fog. Confidence for fog
(around 30%) is higher at KLNS given their proximity to the
coast, with less confidence at KMDT. Moreover, upslope winds at
KJST may contribute to low clouds developing after 06Z, with
restrictions to IFR possible (40% chance) at the site.

Outlook...

Thu...VFR. Partly cloudy and rainfree.

Fri...Light rain possible. VFR to MVFR.

Sat-Sun..Periods of rain with MVFR to IFR conditions.

&&

.CLIMATE...
A handful of record lows were set/tied on Tues morning (April
21st):

Harrisburg`s 29 broke the previous record of 30 degrees set
back in 1956.

Altoona`s 24 broke the previous record of 26 degrees also set
back in 1956.

Williamsport tied it`s record of 25 degrees set back in 1925.

&&

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

&&

$$

WHAT HAS CHANGED...Lambert/Dangelo
KEY MESSAGES...Lambert/Dangelo
DISCUSSION...Lambert/Dangelo
AVIATION...Lambert/Teare
CLIMATE...Dangelo/Beaty

Forecaster's
Discussion: