Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2026

Severe Thunderstorm Warning 69, NWS State College, PA

May 20, 2026Lancaster County, Pennsylvania

NWS State College, PA issued this severe thunderstorm warning at May 20, 2026, 4:16 PM EDT for Lancaster County, Pennsylvania. It was in force for 44 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: May 20, 2026, 4:16 PM EDT (20:16 UTC)
Expired: May 20, 2026, 5:00 PM EDT
In force: 44 min
Issued by: NWS State College, PA
Area: Storm-based polygon
Hail: 0.75 in
Wind: 60.0 mph

County Lancaster County, PA

The radar

The Dover AFB radar (KDOX), 152 km from the middle of the area, began a volume at 20:18 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
May 20, 12:39 PM EDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 8.3 hours before the alert went out and 157 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 47 J/kg
Mixed-layer CIN: -204 J/kg
Mixed-layer LCL: 1752 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: -79 m²/s²
0-3 km storm-relative helicity: -47 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, 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 this severe thunderstorm warning went out at May 20, 2:58 PM EDT, 1 hour 18 minutes earlier.

Area forecast discussion, May 20, 2:58 PM EDT, 1 hour 18 minutes before

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Hazardous weather outlook, May 20, 4:13 PM EDT, 3 minutes before

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In the hours before

Local storm report, May 20, 1:57 PM EDT, 2 hours 19 minutes before

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Special weather statement, May 20, 3:34 PM EDT, 42 minutes before

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Local storm report, May 20, 3:35 PM EDT, 41 minutes before

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Special weather statement, May 20, 3:40 PM EDT, 36 minutes before

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Local storm report, May 20, 3:59 PM EDT, 17 minutes before

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Local storm report, May 20, 4:04 PM EDT, 12 minutes before

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The office that day

Everything else NWS State College, PA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 20, 11:51 AM EDT	Special Weather Statement	CTP	Bedford	24 min
May 20, 12:15 PM EDT	Special Weather Statement	CTP	Bedford	30 min
May 20, 12:45 PM EDT	Special Weather Statement	CTP	Fulton	30 min
May 20, 1:03 PM EDT	Severe Thunderstorm Warning	CTP	Franklin, Fulton	42 min
May 20, 1:43 PM EDT	Severe Thunderstorm Warning	CTP	Franklin	47 min
May 20, 3:27 PM EDT	Severe Thunderstorm Warning	CTP	Dauphin, Lebanon, Schuylkill	48 min
May 20, 3:34 PM EDT	Special Weather Statement	CTP	York	41 min
May 20, 3:40 PM EDT	Special Weather Statement	CTP	Lancaster	35 min
May 20, 3:52 PM EDT	Severe Thunderstorm Warning	CTP	Lancaster, York	38 min
May 20, 4:01 PM EDT	Severe Thunderstorm Warning	CTP	Lancaster	44 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2026 Every severe thunderstorm warning in 2026

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.