Name: Damaging Wind in Pennsylvania, August 4, 2001
Start: 2001-08-04T16:50
End: 2001-08-04T16:50
Location: Pennsylvania

Where it happened

Every event with a place to put it. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

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The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 1

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS State College, PA wrote its last area forecast discussion before the first event at Aug 4, 1:30 PM EST, 3 hours 20 minutes earlier.

Area forecast discussion, Aug 4, 1:30 PM EST, 3 hours 20 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE STATE COLLEGE PA
230 PM EDT SAT AUG 04 2001

WIDELY SCT TSRA DEVELOPING OVR CTP ATTM. THE FRONT OR OUTFLOW
BOUNDARY THAT WAS STALLED OVR SE PORTION OF OUR CWA EARLIER HAS
DSPTD.  AGREE WITH BGM THAT THE REAL "FRONT" IS N OF THE THRUWAY AND
DRAPES FROM THERE SW ACRS LAKE ERIE. THERE IS A WEAK SFC LO OVR IPT
WITH A TROF/WSHFT LINE DRAPING FROM THERE SW INTO THE GULF.

SATELLITE SHOWS IMPRESSIVE SWIRL OFF VA CAPES. BUT BUOYS SHOW NO LO.
THIS SYSTEM IS ALL UP LVL AND IS STALLING FRONT TO OUR N. SINCE THIS
UP LO HAS NO CONNECTION TO THE SFC THE DRY AIR WILL LIKELY REMAIN N
OF THE LAKES AND THE FRONT WILL WASH OUT TO OUR N.

MESO ETA SHOWS STRG LO LVL MOISTURE CONVERGENCE OVR PA THIS AFTN
PEAKING AROUND 21Z. THIS DEVELOPS INTO AN ARC WITH STRONG LO LVL
MOISTURE DIVERGENCE BEHIND IT BY 00Z B4 DSPTG AFTER SS. WILL LEAVE
CHC OF TSRA IN TONIGHT AS ETA AND AVN SHOW ANOTHER WEAK S/W MOVG SE
THRU PA AT 12Z SUN.

ONCE THE S/W DEPARTS SUN AM...THE RIDGE ALOFT BUILDS BACK INTO PA
AND CAPS US. THIS WILL END THE AFTN TSRA REGIME WE STARTED WED. WITH
THE SFC RDG OVR US BY MON TEMPS IN VALS WILL TOP 90 ONCE AGAIN WITH
UNCOMFORTABLE HUMIDITY LEVELS.

IN THE EXTENDED...MOS SHOWS VERY LITTLE DEWPT DRYING SO HI HUMIDITY
LVLS WILL LIKELY CONTINUE THRU MUCH OF NEXT WEEK. ANOTHER FRONT WILL
MAKE A PASS AT US TUE EVE BUT IF AVN IS CORRECT ONLY SFC TROF AND
VORT MAX PASS AND NOT THE ACTUAL FRONT. THAT REMAINS N OF THE NY
THRUWAY AGAIN. THE MRF SHOWS NO RELIEF IN SIGHT UNTIL NEXT WEEKEND.

.CTP...NONE.

HEAD

The radar

The Sterling radar (KLWX), 145 km away, was scanning. The volume nearest the first event began at 21:52 UTC.

Open the radar archive at this moment

Event by event

1 thunderstorm wind. Local standard time, as filed.

Thunderstorm Wind, Lancaster

When: August 4, 4:50 PM EST
Where: Lancaster County, Marietta Afs
Measured: 50 kt (58 mph)
Reported by: EMERGENCY MANAGER
Coordinates: 40.067, -76.567

Trees were reported down in Marietta.

What these are

Thunderstorm Wind: Winds from a thunderstorm of 50 knots (58 mph) or more, or lower winds that caused damage or casualties. Measured gusts are marked MG, estimated EG.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

More

Every storm in Pennsylvania in 2001 Every state in 2001 This day in weather history Warnings in Pennsylvania, August 2001

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 5260645.