Alert archive / Wyoming / Severe Thunderstorm Watches in 2002
Severe Thunderstorm Watch 653
The Storm Prediction Center issued this severe thunderstorm watch at Aug 29, 2002, 1:30 PM MDT for 6 counties in Wyoming. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 29, 2002, 1:30 PM MDT (19:30 UTC)
- Expired
- Aug 29, 2002, 8:00 PM MDT
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
Counties Big Horn County, WY, Fremont County, WY, Hot Springs County, WY, Natrona County, WY, Park County, WY, Washakie County, WY
The radar
The Riverton/Lander radar (KRIW), 91 km from the middle of the area, began a volume at 19:31 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
2 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 29, 2:52 PM MDT | Severe Thunderstorm Warning | RIW | Park | 38 min |
| Aug 29, 2:54 PM MDT | Severe Thunderstorm Warning | RIW | Park | 51 min |
The nearest sounding before it
Riverton, WY (KRIW), launched 12:00Z, 7.5 hours before the alert went out and 89 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
- 324 J/kg
- Mixed-layer CIN
- -237 J/kg
- Mixed-layer LCL
- 1208 m above ground
- 0-6 km bulk shear
- 26 kt
- 0-1 km storm-relative helicity
- 17 m²/s²
- 0-3 km storm-relative helicity
- 55 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000 WWUS20 KWNS 291929 SEL3 SPC WW 291930 WYZ000-300200- URGENT - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WATCH NUMBER 653 AFWA-OFFUTT AFB IN SPC BACKUP CAPACITY-OMAHA NEB 130 PM MDT THU AUG 29 2002 AFWA-OFFUTT AFB-OMAHA NEB AS THE SPC BACKUP HAS ISSUED A SEVERE THUNDERSTORM WATCH FOR PORTIONS OF WESTERN AND CENTRAL WYOMING EFFECTIVE THIS THURSDAY AFTERNOON AND EVENING FROM 130 PM UNTIL 800 PM MDT. 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 85 STATUTE MILES EAST AND WEST OF A LINE FROM 30 MILES NORTH OF CODY WYOMING TO 60 MILES SOUTHEAST OF LANDER WYOMING. 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. DISCUSSION...THUNDERSTORMS WILL BECOME SCATTERED ACROSS WW THIS AFTERNOON...AS SHORTWAVE TROUGH LIFTS NEWD OUT OF UT. MODERATE INSTABILITY AND LOW FREEZING/WBZ LEVELS WILL INCREASE THE THREAT OF LARGE HAIL WITH THESE STORMS THROUGH THE EARLY EVENING. 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 24025. ...EVANS 445,1071 421,1061 421,1093 445,1104
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 29, 1:05 PM MDT | Severe Thunderstorm Watch | SPC | Carbon, Sweetwater | 7 hr |
| Aug 29, 2:45 PM MDT | Severe Thunderstorm Watch | SPC | Goshen, Laramie, Platte | 7 hr |
| Aug 29, 3:40 PM MDT | Severe Thunderstorm Watch | SPC | Campbell, Crook, Weston | 6 hr |
Nearby
Severe Thunderstorm Watches in Wyoming, 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.