Central PA Spring 2026 Discussion/Obs Thread

[Yardstickgozinya]

Nws take on Sunday's severe weather threat. Unfortunately, hail along with a damaging wind threat seems to be the main threat Sunday,  for those of us near and in the corridor of slight risk according to the nws

 

 

Area Forecast Discussion
National Weather Service State College PA
502 AM EDT Sat Mar 21 2026

.WHAT HAS CHANGED...
Dense Fog Advisory for a portion of east-central PA until 8AM
Severe thunderstorm risk level increased from 1 to 2 for Sunday
over south central PA

&&

.KEY MESSAGES...
1) Low visibility in dense fog could make driving hazardous
early this morning across portions of east-central PA

2) First weekend of Spring warmup precedes rain and severe
thunderstorm risk Sunday afternoon into Sunday night

&&

.DISCUSSION...
KEY MESSAGE 1: Low visibility in dense fog could make driving
hazardous early this morning across portions of east-central PA

Temporary clearing in the wake of yesterdays rainfall has
resulted in patchy to locally dense fog formation across
portions of east central PA. Visibility trends have been
improving on the margin upon the arrival of lower cloud deck
continuing to expand southeastward per IR satellite imagery.
Coordinated with PHI on issuance of DFA until 8AM with several
ASOS and RWIS sites reporting visby below 1000ft or <1/4 mile.

KEY MESSAGE 2: First weekend of Spring warmup precedes rain and
severe thunderstorm risk Sunday afternoon into Sunday night

A nice start to Spring this weekend with fcst highs ramping 15
to 30F above the historical average by Sunday. This surge of
warmth will be brief and followed by a noticeable cooldown on
Monday with max temps 20-30 degrees lower than Sunday.

SPC expanded the level 2/slight risk outlook from the Upper
Ohio Valley into south central PA (south of I-80) for Sunday
afternoon and evening. CAPE and 0-6km shear profiles appear
rather favorable for organized severe storms ahead of a
southeastward advancing cold front. Large hail probs are
relatively high with 700-500mb lapse rates 7-7.5 C/km and
essentially match the damaging wind probs.

 

[mahantango#1]

.31 rain last evening. Monthly total for March so far 4.94

[Yardstickgozinya]

I had to edit my above post. For some reason, I woke up thinking this was Sunday. lol

[pawatch]

8 hours ago, Itstrainingtime said:

Finished Friday with .36" of rain 

.24” of an inch here yesterday. High of 53 degrees 

[Mount Joy Snowman]

Low of 46 with .37” of rain. Off to Strasburg with the kids. Have a great one!

[ChescoWx]

Updated annual average temperatures for suburban Chester County PA vs the PHL Airport....UHI FTW! In fact in analyzing the warming slope - PHL is now warming at a 6x faster rate than the Philly burbs!

[Jns2183]

Today back in 1958 the area was in the middle of the 2nd greatest snowstorm in Pennsylvania history. Below are the all-time 3 day snowstorms across our state. The top 2 storms both were in our local area with the Blizzard of February 1899 at Coatesville with 52.4" and the 50.0" just off the PA Turnpike at Morgantown leading the way. Of note that same storm in 1958 also featured the 49" that was recorded just off the PA Turnpike at Devault. I have also included the hand written NWS COOP March 1958 observations for both Morgantown and Devault.

I thought you might enjoy these graphs

Sent from my SM-S731U using Tapatalk

[Yardstickgozinya]

Basically expanded to include most of the state. From what I gather, severe storms will be quite isolated , but carry the risk of large hail up to the size of golf balls.  Spc added that they may need to add a elevated tornado risk to the outlook. Main bust threat is lack of moisture  return. Thunderstorms are expected to expand in coverage for the late afternoon and evening, but are expected to be more elevated at that point.  

https://www.spc.noaa.gov/products/outlook/day2otlk.html

Hail sig hatching level 1

Tornado probability 2%