Alert archive / Oklahoma / Severe Thunderstorm Watches in 2002
Severe Thunderstorm Watch 89
The Storm Prediction Center issued this severe thunderstorm watch at Apr 13, 2002, 4:45 AM CDT for 12 counties in Oklahoma; 7 counties in Texas. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- Apr 13, 2002, 4:45 AM CDT (09:45 UTC)
- Expired
- Apr 13, 2002, 10:00 AM CDT
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
Counties Beckham County, OK, Blaine County, OK, Comanche County, OK, Custer County, OK, Dewey County, OK, Greer County, OK, Harmon County, OK, Jackson County, OK, Kiowa County, OK, Roger Mills County, OK, Tillman County, OK, Washita County, OK, Archer County, TX, Baylor County, TX, Foard County, TX, Hardeman County, TX, Knox County, TX, Wichita County, TX, Wilbarger County, TX
The radar
The Altus AFB radar (KFDR), 76 km from the middle of the area, began a volume at 09:48 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.
Warnings issued inside it
8 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 13, 5:58 AM CDT | Severe Thunderstorm Warning | OUN | Greer, Harmon | 47 min |
| Apr 13, 6:44 AM CDT | Severe Thunderstorm Warning | OUN | Greer | 46 min |
| Apr 13, 6:52 AM CDT | Severe Thunderstorm Warning | OUN | Comanche, Tillman | 38 min |
| Apr 13, 7:19 AM CDT | Severe Thunderstorm Warning | OUN | Harmon, Jackson | 41 min |
| Apr 13, 7:31 AM CDT | Severe Thunderstorm Warning | OUN | Comanche, Cotton, Greer, Kiowa, Tillman | 44 min |
| Apr 13, 7:58 AM CDT | Severe Thunderstorm Warning | OUN | Jackson, Tillman | 47 min |
| Apr 13, 8:43 AM CDT | Severe Thunderstorm Warning | OUN | Cotton, Tillman | 62 min |
| Apr 13, 9:34 AM CDT | Severe Thunderstorm Warning | OUN | Archer, Clay | 56 min |
The nearest sounding before it
Norman, OK (KOUN), launched 00:00Z, 9.8 hours before the alert went out and 149 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
- 271 J/kg
- Mixed-layer CIN
- -75 J/kg
- Mixed-layer LCL
- 934 m above ground
- 0-6 km bulk shear
- 45 kt
- 0-1 km storm-relative helicity
- -26 m²/s²
- 0-3 km storm-relative helicity
- 53 m²/s²
- Significant tornado parameter
- -0.0
- Supercell composite
- -0.2
The text
As transmitted, in the capitals the NWS used until 2016.
000 WWUS20 KWNS 130931 SEL9 SPC WW 130926 OKZ000-TXZ000-131500- URGENT - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WATCH NUMBER 89 STORM PREDICTION CENTER NORMAN OK 426 AM CDT SAT APR 13 2002 THE STORM PREDICTION CENTER HAS ISSUED A SEVERE THUNDERSTORM WATCH FOR PORTIONS OF WESTERN OKLAHOMA NORTHWEST TEXAS EFFECTIVE THIS SATURDAY MORNING FROM 445 AM UNTIL 1000 AM CDT. HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS. THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 45 STATUTE MILES EAST AND WEST OF A LINE FROM 55 MILES NORTH OF CLINTON OKLAHOMA TO 55 MILES SOUTHWEST OF WICHITA FALLS TEXAS. REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE TORNADOES. OTHER WATCH INFORMATION... CONTINUE...WW 88... DISCUSSION...STRONG/SEVERE THUNDERSTORMS ARE EXPECTED TO CONTINUE TO INCREASE IN AREAL COVERAGE THROUGH THE MORNING HOURS AS UPPER TROUGH OVER NORTHERN NM SHIFTS EASTWARD. MODERATE ELEVATED INSTABILITY AND STRONG VERTICAL SHEAR PROFILES SUGGEST THE POTENTIAL FOR SUPERCELLS PRODUCING LARGE HAIL IN THIS REGION. AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM MOTION VECTOR 27030. ...HART 360,0982 332,0982 332,0995 360,1000 WWUS20 KWNS 130931 SEL9 SPC WW 130926 OKZ000-TXZ000-131500- URGENT - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WATCH NUMBER 89 STORM PREDICTION CENTER NORMAN OK 426 AM CDT SAT APR 13 2002 THE STORM PREDICTION CENTER HAS ISSUED A SEVERE THUNDERSTORM WATCH FOR PORTIONS OF WESTERN OKLAHOMA NORTHWEST TEXAS EFFECTIVE THIS SATURDAY MORNING FROM 445 AM UNTIL 1000 AM CDT. HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS. THE SEVERE THUNDERSTORM WATCH AREA IS ALONG AND 45 STATUTE MILES EAST AND WEST OF A LINE FROM 55 MILES NORTH OF CLINTON OKLAHOMA TO 55 MILES SOUTHWEST OF WICHITA FALLS TEXAS. REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE TORNADOES. OTHER WATCH INFORMATION... CONTINUE...WW 88... DISCUSSION...STRONG/SEVERE THUNDERSTORMS ARE EXPECTED TO CONTINUE TO INCREASE IN AREAL COVERAGE THROUGH THE MORNING HOURS AS UPPER TROUGH OVER NORTHERN NM SHIFTS EASTWARD. MODERATE ELEVATED INSTABILITY AND STRONG VERTICAL SHEAR PROFILES SUGGEST THE POTENTIAL FOR SUPERCELLS PRODUCING LARGE HAIL IN THIS REGION. AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM MOTION VECTOR 27030. ...HART 360,0982 332,0982 332,0995 360,1000
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 12, 7:45 PM CDT | Severe Thunderstorm Watch | SPC | Beaver, Cimarron, Texas | 6 hr |
| Apr 12, 11:30 PM CDT | Tornado Watch | SPC | Beckham, Greer, Harmon, Roger Mills, Texas | 6 hr |
| Apr 13, 7:45 AM CDT | Severe Thunderstorm Watch | SPC | Bryan, Caddo, Canadian, Carter, Cleveland, Coal and 16 more | 5 hr |
| Apr 13, 10:45 AM CDT | Severe Thunderstorm Watch | SPC | Atoka, Bryan, Carter, Choctaw, Johnston, Love and 4 more | 5 hr |
| Apr 13, 5:00 AM CDT | Tornado Watch | SPC | Armstrong, Briscoe, Carson, Castro, Childress, Collingsworth and 13 more | 5 hr |
| Apr 13, 3:45 PM CDT | Severe Thunderstorm Watch | SPC | Bailey, Briscoe, Childress, Cochran, Cottle, Crosby and 16 more | 5 hr |
Nearby
Severe Thunderstorm Watches in Oklahoma, 2002Severe Thunderstorm Watches in Texas, 2002Every severe thunderstorm watch in 2002
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.