Alert archive / Wyoming / Tornado Warnings in 1991
Tornado Warning 2, NWS Riverton, WY
NWS Riverton, WY issued this tornado warning at May 17, 1991, 8:14 PM MDT for Fremont County, Wyoming. It was in force for 31 min.
The area
The counties it named.
The facts
- Issued
- May 17, 1991, 8:14 PM MDT (02:14 UTC)
- Expired
- May 17, 1991, 8:45 PM MDT
- In force
- 31 min
- Issued by
- NWS Riverton, WY
- Area
- Whole counties
County Fremont County, WY
The nearest sounding before it
Lander/Hunt Fiel, WY (KLND), launched 00:00Z, 2.2 hours before the alert went out and 25 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
- 6 J/kg
- Mixed-layer CIN
- -88 J/kg
- Mixed-layer LCL
- 1060 m above ground
- 0-6 km bulk shear
- 54 kt
- 0-1 km storm-relative helicity
- 207 m²/s²
- 0-3 km storm-relative helicity
- 408 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 KLND 180215 TORLND WYC013-180245- BULLETIN - EBS ACTIVATION REQUESTED TORNADO WARNING NATIONAL WEATHER SERVICE LANDER WY 814 PM MDT FRI MAY 17 1991 THE NATIONAL WEATHER SERVICE IN LANDER WY HAS ISSUED A TORNADO WARNING EFFECTIVE UNTIL 845 PM MDT FOR PEOPLE IN THE FOLLOWING LOCATIONS...... IN WEST CENTRAL WYOMING ...CENTRAL FREMONT COUNTY AT 800 PM MDT TWO TORNADOES WERE SPOTTED ON THE GROUND NEAR THE CITIES OF RIVERTON AND FORT WASHAKIE. AN OFF DUTY POLICE OFFICER SAW ONE TORNADO TOUCH DOWN ABOUT 15 MILES NORTH OF RIVERTON. THE RIVERTON SHERRIFS OFFICE REPORTED ANOTHER TORNADO 20 MILES NORTHWEST OF FORT WASHAKIE. KPL IF YOU ARE IN THE PATH OF A TORNADO...THE SAFEST PLACE IS A BASEMENT. GET UNDER A WORKBENCH OR PIECE OF STURDY FURNITURE. IF NO BASEMENT IS AVAILABLE...SEEK SHELTER IN AN INTERIOR ROOM SUCH AS A CLOSET ON THE LOWEST FLOOR. USE BLANKETS...PILLOWS... OR CUSHIONS TO COVER YOUR BODY. AVOID WINDOWS.
What forecasters said that day
The local office's own words before this tornado 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, May 17, 4:39 PM MDT, 3 hours 35 minutes before
WYZ008-009-172330- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE LANDER WY 438 PM MDT FRI MAY 17 1991 ...THUNDERSTORMS WERE MOVING INTO WESTERN FREMONT COUNTY... AT 430 PM MDT RADAR AND LIGHTNING DETECTION CHARTS SHOWED THUNDERSTORMS MOVING INTO WESTERN FREMONT COUNTY. MOST OF THE THUNDERSTORMS WERE IN SUBLETTE COUNTY MOVING NORTHEAST AT AROUND 25 MILES AN HOUR. AREAS SOUTH OF BIG PINEY WERE RECEIVING HEAVY RAIN AND SMALL HAIL. FARSON...45 MILES SOUTHWEST OF SOUTH PASS CITY...HAD NUMEROUS LIGHTNING STRIKES WITH THE THUNDERSTORMS. PEOPLE IN NORTHERN SUBLETTE COUNTY AND WESTERN FREMONT COUNTY SHOULD BE PREPARED FOR THUNDERSTORMS. SOME OF THESE THUNDERSTORMS MAY CONTAIN HEAVY RAIN...STRONG WINDS AND SMALL HAIL. MOVE TO SHELTER IF LIGHTNING OR STRONG STORMS APPROACH YOUR AREA. ALSO...DO NOT TRY TO DRIVE THROUGH WATER OVER ROADS. LYNOTT
Special weather statement, May 17, 6:15 PM MDT, 1 hour 59 minutes before
WYZ008-009-010-180130- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE LANDER WY 615 PM MDT FRI MAY 17 1991 ...THUNDERSTORMS WERE INCREASING ACROSS WEST CENTRAL WYOMING... AT 605 PM MDT THE LANDER AIRPORT HAD A THUNDERSTORM WITH DANGEROUS LIGHTNING. RAIN WAS FALLING ACROSS MOST OF WEST CENTRAL WYOMING AND SMALL HAIL WAS REPORTED NEAR PINEDALE. THE THUNDERSTORMS WERE MOVING NORTHEAST AT AROUND 25 MILES AN HOUR. THE WIND RIVER BASIN CAN EXPECT THUNDERSTORMS WITH RAIN FOR THE NEXT HOUR. PEOPLE IN WEST CENTRAL WYOMING...ESPECIALLY FREMONT COUNTY...SHOULD BE PREPARED FOR THUNDERSTORMS. SOME OF THESE THUNDERSTORMS MAY CONTAIN HEAVY RAIN...STRONG WINDS AND SMALL HAIL. MOVE TO SHELTER IF LIG`HTNING OR A STRONG STORM APPROACHES. ALSO...DO NOT TRY TO DRIVE THROUGH WATER OVER ROADS. LYNOTT
The office that day
Everything else NWS Riverton, WY issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 18, 5:27 PM MDT | Severe Thunderstorm Warning | RIW | Park | 63 min |
Nearby
Tornado Warnings in Wyoming, 1991Every tornado warning in 1991Tornadoes in 1991
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.