Alert archive / Pennsylvania / Flash Flood Warnings in 1991

Flash Flood Warning 5, NWS State College, PA

August 20, 1991York County, Pennsylvania

NWS State College, PA issued this flash flood warning at Aug 20, 1991, 11:01 AM EDT for York County, Pennsylvania. It was in force for 119 min.

The area

The counties it named.

The facts

Issued
Aug 20, 1991, 11:01 AM EDT (15:01 UTC)
Expired
Aug 20, 1991, 1:00 PM EDT
In force
119 min
Issued by
NWS State College, PA
Area
Whole counties

County York County, PA

The nearest sounding before it

Atlantic City In, NJ (KACY), launched 12:00Z, 3.0 hours before the alert went out and 198 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-pSkew-T log-p diagram, Atlantic City In, NJ at 12:00Z on 1991-08-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 772 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Atlantic City In, NJ at 12:00Z on 1991-08-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 9 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
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
772 J/kg
Mixed-layer CIN
-39 J/kg
Mixed-layer LCL
615 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
9 m²/s²
0-3 km storm-relative helicity
65 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 20, 11:16 AM EDTSevere Thunderstorm WarningCTPLancaster59 min
Aug 20, 7:22 PM EDTSevere Thunderstorm WarningCTPAdams, York68 min

Nearby

Flash Flood Warnings in Pennsylvania, 1991Every flash flood warning in 1991

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.