Central PA Summer 2026 Discussion/Obs Thread

[Yardstickgozinya]

Thunderstorms starting to initiate in Northwestern pennsylvania in an  environment with over 5000jkg+ available in the area that they are initiating in .

[Yardstickgozinya]

Sheer vectors and storm motions appear to all generally be in the same direction, so that should help keep any tornado threat somewhat low. Especially down our way. 

[Blizzard of 93]

.56 rain today in Marysville.

1.25 total for the week.

[mahantango#1]

10 hours ago, WmsptWx said:

Unbelievably dark out right now.

Here too, thought we were headed to dusk.

[mahantango#1]

.76 rain today.

[mahantango#1]

Good lightning show to my north.

[pawatch]

We’re getting hit hard up here. Everybody be safe.

[Yardstickgozinya]

That's pretty incredible. I don't know how much of this is going to come through, i'll echo @pawatch and say, stay safe out there. 

 

 

[Yardstickgozinya]

I took the snapshot below at 4:36am The nam brings this newly developed complex over the lakes through western Pa The rrfs and hrrr target  Cpa,with some pretty potent storms later this morning with that same Lake Erie complex. 

 

 

[mahantango#1]

Who could sleep through what I experienced during the night? Continuous lightning for hours, thunder and heavy rain at times. Almost 2" fell since 11:45pm.

[Yardstickgozinya]

5:30am update on the monster coming off the Glaks. 

 

[mahantango#1]

1 hour ago, Yardstickgozinya said:

5:30am update on the monster coming off the Glaks. 

 

 

US National Weather Service State College PA

 

 

 

As the overnight's storms push to the southeast, another round is beginning to move in from the northwest. The environment doesn't look very supportive, so this is anticipated to weaken as it pushes southeast. All hazards threat for activity later in the afternoon/evening

[AccuChris]

Since midnight, picked up 2.85” of rain, in the last 24 hours 3.89” and month to date its 4.58” here in Lebanon. Amazing. Anything else today will be just pure trouble


.

[mahantango#1]

Flood Watch
National Weather Service State College PA
242 AM EDT Thu Sep 3 2026

PAZ004>006-010>012-017>019-024>028-033>037-041-042-045-046-049>053-
056>059-063>066-040400-
/O.NEW.KCTP.FA.A.0016.260903T0642Z-260904T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Warren-McKean-Potter-Elk-Cameron-Northern Clinton-Clearfield-
Northern Centre-Southern Centre-Cambria-Blair-Huntingdon-Mifflin-
Juniata-Somerset-Bedford-Fulton-Franklin-Tioga-Northern Lycoming-
Sullivan-Southern Clinton-Southern Lycoming-Union-Snyder-Montour-
Northumberland-Columbia-Perry-Dauphin-Schuylkill-Lebanon-Cumberland-
Adams-York-Lancaster-
Including the cities of Altoona, Johnstown, Mifflintown, Somerset,
Lancaster, Philipsburg, Berwick, Wellsboro, Williamsport, Danville,
DuBois, Lewistown, Huntingdon, Sunbury, Bloomsburg, Newport, Renovo,
Lewisburg, Bradford, Mount Union,
St. Marys, McConnellsburg, Mansfield, Selinsgrove, Harrisburg,
Hershey, Warren, Gettysburg, Shamokin, Pottsville, Coudersport,
Chambersburg, Lock Haven, Emporium, York, Trout Run, Laporte,
Clearfield, Bedford, Ridgway, Lebanon, State College, and Carlisle
242 AM EDT Thu Sep 3 2026

...FLOOD WATCH IN EFFECT THROUGH THIS EVENING...

* WHAT...Flash flooding caused by excessive rainfall is possible.

* WHERE...A portion of central Pennsylvania, including the following
  areas, Adams, Bedford, Blair, Cambria, Cameron, Clearfield,
  Columbia, Cumberland, Dauphin, Elk, Franklin, Fulton, Huntingdon,
  Juniata, Lancaster, Lebanon, McKean, Mifflin, Montour, Northern
  Centre, Northern Clinton, Northern Lycoming, Northumberland, Perry,
  Potter, Schuylkill, Snyder, Somerset, Southern Centre, Southern
  Clinton, Southern Lycoming, Sullivan, Tioga, Union, Warren and
  York.

* WHEN...Through this evening.

* IMPACTS...Excessive runoff may result in flooding of rivers,
  creeks, streams, and other low-lying and flood-prone locations.

* ADDITIONAL DETAILS...
  - Additional, multiple rounds of heavy rain from thunderstorms will
    create the threat for flash flooding of streams, creeks and poor
    drainage areas today through early tonight. Rainfall rates could
    exceed 3 inches per hour where several storms track
    east-southeast across the same locations. There should be a lull
    in the rain for several hours during the late morning and early
    afternoon hours today, before the thunderstorms greatly increase
    in number once again across Central Pennsylvania and the
    Susquehanna Valley.
  - http://www.weather.gov/safety/flood

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Please monitor later forecasts and be prepared to take action should
Flash Flood Warnings be issued.

&&

[mahantango#1]

Strong to severe thunderstorms with damaging winds and heavy
rainfall are expected once again today through early tonight.

[Mount Joy Snowman]

Low of 68 with 1.75” of rainfall. Man, what a night. Multiple rounds of heavy rain with loads of T&L. Can’t believe our son slept through it all, daughter not so much. 

[mahantango#1]

256
FXUS61 KCTP 031135
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
735 AM EDT Thu Sep 3 2026

.WHAT HAS CHANGED...
* Issued a Flash Flood Watch for all of our CWA through Midnight
  this Thursday night.

&&

.KEY MESSAGES...
1) Late summer surge of heat and humidity continues with a
severe thunderstorm and excessive rainfall threat through
this Thursday evening

&&

.DISCUSSION...
KEY MESSAGE 1: Late summer surge of heat and humidity continues with a
severe thunderstorm and excessive rainfall threat through
this Thursday evening

Main change this forecast cycle was to issue a Flash Flood
Watch for the entire CWA based on the current wide distribution
of moderate to heavy rain and embedded/training TSRA along with
a HREF/NAM/MRMS blend of short range model guidance and remote
sensing.

A seemingly endless train of mid/upper level impulses riding ESE
along the southern edge of a persistent jet and within a region
of broad upper level diffluence and anomalously high PWATs of
nearly 2 inches will continue to interact with numerous,
converging convective outflow boundaries to produce several more
bouts of heavy showers/TSRA today through at least early
tonight.

Basin "Average" rainfall across the CWA will likely range
between 0.75 to 1.25 inches but as we saw Wed/Wednesday night,
training/and back-building TSRA could easily dump over 3 inches
of rain in just an hour and lead to significant flash flooding.

The target areas for the heaviest rainfall today and this
evening should be the Southwest half of the CWA as a well-
defined outflow boundary has pushed into southern PA early
today. We do expect the airmass to recover quickly late this
morning/early this afternoon as this first MCS moves SE.
However, a glance just to the left shows another developing MCS
close on its heels over West-Central Lake Erie. This feature is
progged by high res near term model guidance to track SE twd
the laurel and diminish by 14-15Z. By 19-20Z today, more TSRA
fire across Northern PA and a second larger area
follows for this evening over a similar part of the state that
experience the heavy rain over the past 24 hours.

Additionally, increased southwest to westerly flow today will
continue to pump in the late summer heat and very high
dewpoints. A heat advisory remains in effect from 11a-8p
Thursday across a portion of south central PA where max heat
index values are projected to reach/exceed 100F.

As mentioned above, SPC`s severe risk are will encompass
primarily the SW half of the state where ML CAPE will be the
highest, but the MRGL risk area will cover practically the
entire rest of Eastern PA.

An upper level trough passage favors one final round of showers
and storms on Friday, but fortunately the Labor Day weekend is
trending dry. The upper ridge is forecast to retrograde by the
end of the week which allows for a return to more seasonal
temperatures and lower humidity this weekend into early next
week.

&&

[anotherman]

Low of 68 with 1.75” of rainfall. Man, what a night. Multiple rounds of heavy rain with loads of T&L. Can’t believe our son slept through it all, daughter not so much. 

It’s literally like living in the tropics. I cannot wait for this disgusting air to be swept out of here tomorrow.

[ChescoWx]

Some more impressive rain totals since yesterday. Atlgen 1.59" / Chester Springs 1.40" / East Nantmeal 1.80" / Warwick 1.32" / Devault 1.78" / Kennett Square 1.22" / West Bradford 2.01" / Avondale 2N 0.80" /West Chester 1.29" and West Grove 0.92"

 

 

[mahantango#1]

10 minutes ago, anotherman said:

It’s literally like living in the tropics. I cannot wait for this disgusting air to be swept out of here tomorrow.