Alert archive / Wyoming / Tornado Warnings in 2002
Tornado Warning 2, NWS Riverton, WY
NWS Riverton, WY issued this tornado warning at Aug 21, 2002, 3:53 PM MDT for Big Horn County, Wyoming. It was in force for 52 min. 1 report 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
- Aug 21, 2002, 3:53 PM MDT (21:53 UTC)
- Expired
- Aug 21, 2002, 4:45 PM MDT
- In force
- 52 min
- Issued by
- NWS Riverton, WY
- Area
- Whole counties
County Big Horn County, WY
The radar
The Billings radar (KBLX), 155 km from the middle of the area, began a volume at 21:54 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.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Aug 21, 4:05 PM MDT | Hail 1.75 | Emblem, WY |
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.
The nearest sounding before it
Riverton, WY (KRIW), launched 12:00Z, 9.9 hours before the alert went out and 165 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
- 82 J/kg
- Mixed-layer CIN
- -249 J/kg
- Mixed-layer LCL
- 2084 m above ground
- 0-6 km bulk shear
- 51 kt
- 0-1 km storm-relative helicity
- 8 m²/s²
- 0-3 km storm-relative helicity
- 205 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.1
The text
As transmitted, in the capitals the NWS used until 2016.
000 WFUS55 KRIW 212153 TORRIW WYC003-212245- BULLETIN - EAS ACTIVATION REQUESTED TORNADO WARNING NATIONAL WEATHER SERVICE RIVERTON WY 353 PM MDT WED AUG 21 2002 THE NATIONAL WEATHER SERVICE IN RIVERTON HAS ISSUED A * TORNADO WARNING FOR... CENTRAL BIG HORN COUNTY IN NORTH CENTRAL WYOMING * UNTIL 445 PM MDT * AT 353 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A THUNDERSTORM WITH A POSSIBLE TORNADO OVER WEST CENTRAL BIG HORN COUNTY...OR ABOUT 20 MILES WEST OF GREYBULL...MOVING NORTHEAST AT 35 MPH. * THE TORNADO IS EXPECTED TO BE... OVER RURAL CENTRAL BIG HORN COUNTY IN NORTH CENTRAL WYOMING AROUND 410 PM MDT OVER RURAL NORTHERN BIG HORN COUNTY IN NORTH CENTRAL WYOMING AROUND 430 PM MDT THIS TORNADO WARNING REPLACES THE SEVERE THUNDERSTORM WARNING PREVIOUSLY ISSUED FOR THE WARNED AREA. IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER IN A NEARBY STURDY BUILDING. AS A LAST RESORT...SEEK REFUGE IN A CULVERT...DITCH OR LOW SPOT AND COVER YOUR HEAD WITH YOUR HANDS. BEWARE OF THE THREAT OF RISING WATER. REPORT SEVERE WEATHER TO THE NEAREST LAW ENFORCEMENT AGENCY. THEY WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST OFFICE IN RIVERTON. $$ LAT...LON 4452 10856 4440 10837 4469 10784 4489 10806 SKRBAC WCJIN-WYNW
The office that day
Everything else NWS Riverton, WY issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 21, 3:48 PM MDT | Severe Thunderstorm Warning | RIW | Big Horn | 42 min |
| Aug 21, 3:53 PM MDT | Tornado Warning | RIW | Big Horn | 52 min |
| Aug 21, 4:58 PM MDT | Severe Thunderstorm Warning | RIW | Johnson | 62 min |
| Aug 21, 5:28 PM MDT | Severe Thunderstorm Warning | RIW | Johnson, Natrona | 47 min |
Nearby
Tornado Warnings in Wyoming, 2002Every tornado warning in 2002Tornadoes 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.