Alert archive / Oklahoma / Flash Flood Warnings in 1991

Flash Flood Warning 4, NWS Norman, OK

April 17, 1991Choctaw County, Oklahoma

NWS Norman, OK issued this flash flood warning at Apr 17, 1991, 8:36 PM CDT for Choctaw County, Oklahoma. It was in force for 2 hr.

The area

The counties it named.

The facts

Issued
Apr 17, 1991, 8:36 PM CDT (01:36 UTC)
Expired
Apr 17, 1991, 10:45 PM CDT
In force
2 hr
Issued by
NWS Norman, OK
Area
Whole counties

County Choctaw County, OK

The nearest sounding before it

Longview/Gregg, TX (KGGG), launched 00:00Z, 1.6 hours before the alert went out and 206 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, Longview/Gregg, TX at 00:00Z on 1991-04-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1509 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, Longview/Gregg, TX at 00:00Z on 1991-04-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 60 square meters per square second.193958Sfc1 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
1509 J/kg
Mixed-layer CIN
-2 J/kg
Mixed-layer LCL
653 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
60 m²/s²
0-3 km storm-relative helicity
125 m²/s²
Significant tornado parameter
0.3
Supercell composite
1.8

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 Norman, OK issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 17, 7:40 PM CDTSevere Thunderstorm WarningOUNChoctaw65 min
Apr 17, 8:02 PM CDTFlash Flood WarningOUNAtoka, Bryan118 min

Nearby

Flash Flood Warnings in Oklahoma, 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.