Alert archive / Oklahoma / Severe Thunderstorm Warnings in 1987
Severe Thunderstorm Warning 252, NWS Norman, OK
NWS Norman, OK issued this severe thunderstorm warning at Jul 12, 1987, 6:40 PM CDT for Blaine County, Custer County, Oklahoma. It was in force for 65 min. 2 reports came from inside the area while it was in force.
The area
The counties it named, with what was reported inside it.
The facts
- Issued
- Jul 12, 1987, 6:40 PM CDT (23:40 UTC)
- Expired
- Jul 12, 1987, 7:45 PM CDT
- In force
- 65 min
- Issued by
- NWS Norman, OK
- Area
- Whole counties
Counties Blaine County, OK, Custer County, OK
The radar
The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Jul 12, 7:00 PM CDT | Hail 0.75 | Custer, OK | |
| Jul 12, 7:30 PM CDT | Hail 0.75 | Custer, OK |
NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in. Storm Data before 1996 records only tornadoes, thunderstorm wind and hail.
The nearest sounding before it
Ok Cty/Will Rgrs, OK (KOKC), launched 12:00Z, 11.7 hours before the alert went out and 109 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.
- Mixed-layer CAPE
- 2074 J/kg
- Mixed-layer CIN
- -110 J/kg
- Mixed-layer LCL
- 747 m above ground
- 0-6 km bulk shear
- 15 kt
- 0-1 km storm-relative helicity
- 191 m²/s²
- 0-3 km storm-relative helicity
- 222 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000
TTAA00 KOKC 122340
SVROKC
OKC011-039-130045-
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE OKLAHOMA CITY OK
640 PM CDT SUN JUL 12 1987
THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM WARNING
EFFECTIVE UNTIL 745 PM CDT FOR PEOPLE IN THE FOLLOWING COUNTIES...
IN NORTHWEST OKLAHOMA
...BLAINE...CUSTER
AT 640 PM RADAR INDICATED A SEVERE THUNDERSTORM NEAR THOMAS MOVING
TOWARDS THE EAST AT 20 MPH. PERSONS IN THOMAS AND WATONGA ARE IN THE
PATH OF THIS STORM AND CAN EXPECT HAIL UP TO GOLFBALL SIZE AND STRONG
WINDS WITH THIS STORM.
SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 55
MPH...DESTRUCTIVE HAIL...DEADLY LIGHTNING...AWND VERY HEAVY RAIN.
FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR
OF YOUR HOME OR BUSINESS. HEAVY RAINS FLOOD ROADS QUICKLY SO
DON'T DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.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
Special weather statement, Jul 12, 5:37 PM CDT, 1 hour 3 minutes before
SPECIA KSPS 122237 SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE WICHITA FALLS TX 535 PM CDT SUN JUL 12 1987 AT 520PM THE WICHITA FALLS RADAR WAS INDICATING A LINE OF VERY SEVERE THUNDERSTORMS TO THE WEST OF WICHITA FALLS. THE LEADING EDGE OF THIS LINE WAS FROM PONCA CITY TO ELK CITY IN OKLAHOMA AND EXTENDED SOUTHWEST INTO TEXAS. THE LEADING EDGE IN TEXAS WAS JUST NORTHWEST OF CHILDRESS TO WEST OF LUBBOCK TEXAS. THIS LINE IS ABOUT 60 MILES WIDE IN THE NORTHERN PART IN OKLAHOMA TO ABOUT 30 MILES WIDE IN THE SOUTHERN TIP IN TEXAS. MOVEMENT OF THE LINE IS TO THE SOUTHEAST AT 10 TO 15 MILES AN HOUR AND SOME OF THE INDIVIDUAL THUNDERSTORMS WERE MOVING TO THE NORTHEAST AT 20 TO 25 MILES AN HOUR. THE LOCAL FORECAST CALLS FOR THE POSSIBILITY OF SEVERE THUNDERSTORMS IN THE LOCAL AREA LATER TONIGHT. THESE THUNDERSTORMS MAY PRODUCE LARGE HAIL..HEAVY RAINS...GUSTY WINDS... AND DANGEROUS LIGHTNING. KEEP TUNED TO NOAA WEATHR AREA FOR LATER INFORMATION ON THESE DANGEROUS SITUATION. RAMIREZ
Special weather statement, Jul 12, 5:41 PM CDT, 59 minutes before
SPECIA KSPS 122241 COR SPECIAL WEATHER STATEMENT...CORRECTION... NATIONAL WEATHER SERVICE WICHITA FALLS TX 535 PM CDT SUN JUL 12 1987 AT 520PM THE WICHITA FALLS RADAR WAS INDICATING A LINE OF VERY SEVERE THUNDERSTORMS TO THE WEST OF WICHITA FALLS. THE LEADING EDGE OF THIS LINE WAS FROM PONCA CITY TO ELK CITY IN OKLAHOMA AND EXTENDED SOUTHWEST INTO TEXAS. THE LEADING EDGE IN TEXAS WAS JUST NORTHWEST OF CHILDRESS TO WEST OF LUBBOCK TEXAS. THIS LINE IS ABOUT 60 MILES WIDE IN THE NORTHERN PART IN OKLAHOMA TO ABOUT 30 MILES WIDE IN THE SOUTHERN TIP IN TEXAS. MOVEMENT OF THE LINE IS TO THE SOUTHEAST AT 10 TO 15 MILES AN HOUR AND SOME OF THE INDIVIDUAL THUNDERSTORMS WERE MOVING TO THE NORTHEAST AT 20 TO 25 MILES AN HOUR. THE LOCAL FORECAST CALLS FOR THE POSSIBILITY OF SEVERE THUNDERSTORMS IN THE LOCAL AREA LATER TONIGHT. THESE THUNDERSTORMS MAY PRODUCE LARGE HAIL..HEAVY RAINS...GUSTY WINDS... AND DANGEROUS LIGHTNING. KEEP TUNED TO NOAA WEATHER RADIO FOR LATER INFORMATION ON THIS DANGEROUSS SITUATION. RAMIREZ
The office that day
Everything else NWS Norman, OK issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 12, 4:10 PM CDT | Severe Thunderstorm Warning | OUN | Alfalfa, Major | 50 min |
| Jul 12, 4:10 PM CDT | Severe Thunderstorm Warning | OUN | Grant | 50 min |
| Jul 12, 4:41 PM CDT | Severe Thunderstorm Warning | OUN | Major | 19 min |
| Jul 12, 4:50 PM CDT | Severe Thunderstorm Warning | OUN | Blaine, Custer, Dewey, Major | 55 min |
| Jul 12, 4:50 PM CDT | Severe Thunderstorm Warning | OUN | Alfalfa, Garfield, Grant | 55 min |
| Jul 12, 5:43 PM CDT | Severe Thunderstorm Warning | OUN | Blaine, Custer, Dewey, Major | 62 min |
| Jul 12, 6:01 PM CDT | Severe Thunderstorm Warning | OUN | Beckham, Roger Mills | 59 min |
| Jul 12, 6:53 PM CDT | Severe Thunderstorm Warning | OUN | Beckham | 67 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive.