Alert archive / Wyoming / Severe Thunderstorm Warnings in 1998
Severe Thunderstorm Warning 16, NWS Cheyenne, WY
NWS Cheyenne, WY issued this severe thunderstorm warning at May 10, 1998, 1:49 PM MDT for Laramie County, Wyoming. It was in force for 31 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
- May 10, 1998, 1:49 PM MDT (19:49 UTC)
- Expired
- May 10, 1998, 2:20 PM MDT
- In force
- 31 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 19:49 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 |
|---|---|---|---|
| May 10, 2:00 PM MDT | Hail 1.75 | Cheyenne, WY | A thunderstorm produced golf ball size hail along interstate 25, 22 miles north 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, 7.8 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
- 12 J/kg
- Mixed-layer CIN
- -208 J/kg
- Mixed-layer LCL
- 889 m above ground
- 0-6 km bulk shear
- 37 kt
- 0-1 km storm-relative helicity
- 19 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.
059 WUUS1 KCYS 101951 RRA SVRCYS WYC021-102020- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE CHEYENNE WY 149 PM MDT SUN MAY 10 1998 THE NATIONAL WEATHER SERVICE IN CHEYENNE HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... NORTHERN LARAMIE COUNTY IN SOUTHEASTERN WYOMING * UNTIL 220 PM MDT * AT 150 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM 22 MILES NORTH OF CHEYENNE ALONG INTERSTATE 25....AT MILE MARKERS 30 TO 35 MOVING EAST AT 10 MPH.. * THE SEVERE THUNDERSTORM WILL BE NEAR... INTERSTATE 25...22 MILES NORTH OF CHEYENNE. DAMAGING WINDS AND LARGE HAIL ARE LIKELY. GO INSIDE A STURDY BUILDING AND STAY AWAY FROM WINDOWS CMB WCJIN-WYSE
What forecasters said that day
The local office's own words before this severe thunderstorm 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 10, 9:49 AM MDT, 4 hours before
WYZ059>070-NEZ001>003-019>021-054-055-110000- SEVERE WEATHER OUTLOOK NATIONAL WEATHER SERVICE CHEYENNE WY 949 AM MDT SUN MAY 10 1998 THE SEVERE WEATHER POTENTIAL IN THE CHEYENNE NWS COUNTY WARNING AREA IS HIGH TODAY. SPOTTER ACTIVATION WILL LIKELY BE REQUIRED. DISCUSSION...THUNDERSTORMS WILL DEVELOP BY MID AFTERNOON OVER SOUTH CENTRAL AND SOUTHEAST WYOMING AND THEN MOVE INTO EAST CENTRAL WYOMING AND THE NEBRASKA PANHANDLE. THE AIRMASS WILL BE MOIST AND UNSTABLE WITH GOOD WIND SHEAR. THE RESULT FOR AREAS EAST OF THE LARAMIE RANGE WILL BE STORMS THAT PRODUCE HEAVY RAIN...HAIL UP TO ONE AND ONE HALF INCHES AND WIND GUSTS BETWEEN 40 AND 50 MPH AS THEY MOVE TO THE EAST. THE RAIN WILL CAUSE MINOR FLOODING OF URBAN AND LOW LYING AREAS BY LATE AFTERNOON. WCJIN-WYSE-WYNE WEILAND
Special weather statement, May 10, 9:49 AM MDT, 4 hours before
WYZ059>070-NEZ001>003-019>021-054-055-110000- SEVERE WEATHER OUTLOOK NATIONAL WEATHER SERVICE CHEYENNE WY 949 AM MDT SUN MAY 10 1998 THE SEVERE WEATHER POTENTIAL IN THE CHEYENNE NWS COUNTY WARNING AREA IS HIGH TODAY. SPOTTER ACTIVATION WILL LIKELY BE REQUIRED. DISCUSSION...THUNDERSTORMS WILL DEVELOP BY MID AFTERNOON OVER SOUTH CENTRAL AND SOUTHEAST WYOMING AND THEN MOVE INTO EAST CENTRAL WYOMING AND THE NEBRASKA PANHANDLE. THE AIRMASS WILL BE MOIST AND UNSTABLE WITH GOOD WIND SHEAR. THE RESULT FOR AREAS EAST OF THE LARAMIE RANGE WILL BE STORMS THAT PRODUCE HEAVY RAIN...HAIL UP TO ONE AND ONE HALF INCHES AND WIND GUSTS BETWEEN 40 AND 50 MPH AS THEY MOVE TO THE EAST. THE RAIN WILL CAUSE MINOR FLOODING OF URBAN AND LOW LYING AREAS BY LATE AFTERNOON. WCJIN-WYSE-WYNE WEILAND
The office that day
Everything else NWS Cheyenne, WY issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 10, 2:22 PM MDT | Severe Thunderstorm Warning | CYS | Goshen, Laramie | 48 min |
| May 10, 3:10 PM MDT | Severe Thunderstorm Warning | CYS | Goshen | 50 min |
| May 10, 5:49 PM MDT | Severe Thunderstorm Warning | CYS | Goshen | 51 min |
Nearby
Severe Thunderstorm Warnings in Wyoming, 1998Every severe thunderstorm warning 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.