Alert archive / Wyoming / Tornado Warnings in 1998
Tornado Warning 28, NWS Cheyenne, WY
NWS Cheyenne, WY issued this tornado warning at Aug 9, 1998, 2:43 PM MDT for Laramie County, Wyoming. It was in force for 17 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 9, 1998, 2:43 PM MDT (20:43 UTC)
- Expired
- Aug 9, 1998, 3:00 PM MDT
- In force
- 17 min
- Issued by
- NWS Cheyenne, WY
- Area
- Whole counties
County Laramie County, WY
The radar
The Cheyenne radar (KCYS), 20 km from the middle of the area, began a volume at 20:45 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 9, 2:43 PM MDT | Tornado F0 | Cheyenne, WY | A brief tornado moved across open country 10 miles northeast of Cheyenne. |
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
Denver, CO (KDNR), launched 12:00Z, 8.7 hours before the alert went out and 202 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
- 13 J/kg
- Mixed-layer CIN
- -340 J/kg
- Mixed-layer LCL
- 2304 m above ground
- 0-6 km bulk shear
- 14 kt
- 0-1 km storm-relative helicity
- 20 m²/s²
- 0-3 km storm-relative helicity
- 11 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
538 WFUS1 KCYS 092045 RRA TORCYS WYC021-092100- BULLETIN - EAS ACTIVATION REQUESTED TORNADO WARNING NATIONAL WEATHER SERVICE CHEYENNE WY 243 PM MDT SUN AUG 9 1998 THE NATIONAL WEATHER SERVICE IN CHEYENNE HAS ISSUED A * TORNADO WARNING FOR... NORTHEASTERN LARAMIE COUNTY IN SOUTHEASTERN WYOMING * UNTIL 300 PM MDT * AT 240 PM MDT... SPOTTERS INDICATED A TORNADO 10 MILES NORTHEAST OF CHEYENNE...MOVING EAST AT 15 MPH. * THE TORNADO IS EXPECTED TO REMAIN OVER OPEN COUNTRY A TORNADO IS ON THE GROUND GO TO THE BASEMENT IF A BASEMENT IS NOT AVAILABLE...GO TO A SMALL INTERIOR ROOM ON THE LOWEST FLOOR WCJIN-WYSE ROBINSON
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, Aug 9, 10:00 AM MDT, 4 hours 43 minutes before
WYZ059>070-NEZ001>003-019>021-054-055-100000- SEVERE WEATHER OUTLOOK NATIONAL WEATHER SERVICE CHEYENNE WY 1000 AM MDT SUN AUG 9 1998 THE SEVERE WEATHER POTENTIAL IN THE NWS CHEYENNE COUNTY WARNING AREA IS LOW THIS AFTERNOON AND EVENING. SPOTTER ACTIVATION WILL NOT LIKELY BE NECESSARY. DISCUSSION...A FAIRLY MOIST AND UNSTABLE AIR MASS WILL BE OVER THE AREA TODAY. DAYTIME HEATING COMBINED WITH AN UPPER AIR WEATHER FEATURE MOVING ACROSS SOUTHERN WYOMING AND NORTHERN COLORADO WILL CAUSE SCATTERED THUNDERSTORMS THIS AFTERNOON AND EVENING. THESE STORMS ARE EXPECTED TO STAY BELOW SEVERE LIMITS...BUT SOME WILL PRODUCE SMALL HAIL ...HEAVY RAIN AND WIND GUSTS NEAR 50 MPH. WCJIN-WYNE-WYSE JLH
The office that day
Everything else NWS Cheyenne, WY issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 9, 3:21 PM MDT | Tornado Warning | CYS | Laramie | 34 min |
Nearby
Tornado Warnings in Wyoming, 1998Every tornado warning in 1998Tornadoes in 1998
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.