Alert archive / Oklahoma / Severe Thunderstorm Warnings in 1987

Severe Thunderstorm Warning 262, NWS Norman, OK

July 17, 1987Garvin County, Oklahoma

NWS Norman, OK issued this severe thunderstorm warning at Jul 17, 1987, 7:13 PM CDT for Garvin County, Oklahoma. It was in force for 47 min.

The area

The counties it named.

The facts

Issued
Jul 17, 1987, 7:13 PM CDT (00:13 UTC)
Expired
Jul 17, 1987, 8:00 PM CDT
In force
47 min
Issued by
NWS Norman, OK
Area
Whole counties

County Garvin County, OK

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

The nearest sounding before it

Ok Cty/Will Rgrs, OK (KOKC), launched 00:00Z, 0.2 hours before the alert went out and 82 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, Ok Cty/Will Rgrs, OK at 00:00Z on 1987-07-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2242 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, Ok Cty/Will Rgrs, OK at 00:00Z on 1987-07-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 322 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
2242 J/kg
Mixed-layer CIN
-2 J/kg
Mixed-layer LCL
626 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
322 m²/s²
0-3 km storm-relative helicity
573 m²/s²
Significant tornado parameter
3.0
Supercell composite
18.5

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.

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.

In the hours before

Local storm report, Jul 17, 4:12 PM CDT, 3 hours 1 minute before
STORM REPORT
NATIONAL WEATHER SERVICE OKLAHOMA CITY OK
411 PM CDT FRI JUL 17 1987

TIME    COUNTY         REPORT
408 PM  COMANCHE       WINDS GREATER THAN 70 MPH IN INDIAHOMA.

The office that day

Everything else NWS Norman, OK issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 17, 7:13 PM CDTSevere Thunderstorm WarningOUNCleveland, Grady, McClain47 min
Jul 17, 7:58 PM CDTSevere Thunderstorm WarningOUNGarvin, Grady, McClain62 min
Jul 17, 8:32 PM CDTSevere Thunderstorm WarningOUNCaddo, Canadian, Grady43 min
Jul 17, 9:13 PM CDTSevere Thunderstorm WarningOUNCanadian, Grady47 min
Jul 17, 9:55 PM CDTSevere Thunderstorm WarningOUNCanadian, Oklahoma50 min
Jul 17, 10:30 PM CDTSevere Thunderstorm WarningOUNKingfisher, Logan45 min
Jul 17, 10:43 PM CDTSevere Thunderstorm WarningOUNCanadian, Oklahoma32 min
Jul 17, 11:11 PM CDTSevere Thunderstorm WarningOUNLogan, Oklahoma49 min

Nearby

Severe Thunderstorm Warnings in Oklahoma, 1987Every severe thunderstorm warning in 1987

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.