Alert archive / Wyoming / Severe Thunderstorm Warnings in 1989
Severe Thunderstorm Warning 39, NWS Cheyenne, WY
NWS Cheyenne, WY issued this severe thunderstorm warning at Jul 12, 1989, 5:25 PM MDT for Sweetwater County, Wyoming. It was in force for 65 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
- Jul 12, 1989, 5:25 PM MDT (23:25 UTC)
- Expired
- Jul 12, 1989, 6:30 PM MDT
- In force
- 65 min
- Issued by
- NWS Cheyenne, WY
- Area
- Whole counties
County Sweetwater County, WY
The radar
The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Jul 12, 6:00 PM MDT | Hail 0.75 | Sweetwater, 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. Storm Data before 1996 records only tornadoes, thunderstorm wind and hail.
The nearest sounding before it
Lander/Hunt Fiel, WY (KLND), launched 12:00Z, 11.4 hours before the alert went out and 130 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- NaN m above ground
- 0-6 km bulk shear
- 11 kt
- 0-1 km storm-relative helicity
- 86 m²/s²
- 0-3 km storm-relative helicity
- 142 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 KCYS 122325
SVRCYS
WYC037-130030-
BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE CHEYENNE WY
525 PM MDT WED JUL 12 1989
THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM
WARNING EFFECTIVE UNTIL 630 PM MDT FOR PEOPLE IN THE FOLLOWING
COUNTY
IN THE SOUTH CENTRAL PART OF WYOMING
WEST CENTRAL SWEETWATER COUNTY
THIS WARNING INCLUDES THE TOWNS OF GREEN RIVER AND ROCK SPRINGS.
RADAR INDICATED A SEVERE THUNDERSTORM ABOUT 15 MILES SOUTH OF GREEN
RIVER MOVING NORTH AT 25 MILES AN HOUR. IT PRODUCED STRONG GUSTY
WINDS AND BRIEF HEAVY RAIN AS IT WENT OVER THE FLAMING GORGE MARINA
AT 515 PM.
IF YOU ARE CAUGHT OUTSIDE...SEEK SHELTER FROM THE WEATHER IN A
STRONG BUILDING. DAMAGING WIND...LARGE HAIL...VERY HEAVY RAIN...
AND DEADLY LIGHTNING ARE ALL POSSIBLE IN SEVERE THUNDERSTORMS.
STAY INSIDE UNTIL THE STORM PASSES.
DASELERWhat 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, Jul 12, 3:30 PM MDT, 1 hour 55 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE CHEYENNE WY 330 PM MDT WED JUL 12 1989 ...THUNDERSTORMS DEVELOP OVER WYOMING THIS AFTERNOON... WIDESPREAD THUNDERSTORMS DEVELOPED OVER WYOMING THIS AFTERNOON. MOST OF THE STORMS WERE CONCENTRATED OVER NORTHWEST WYOMING...FROM THE YELLOWSTONE NATIONAL PARK TO THE BIG HORN MOUNTAINS. HOWEVER... THUNDERSTORMS ALSO OCCURRED OVER SOUTHWEST WYOMING...THE WIND RIVER MOUNTAINS...AND THE NORTHEAST PLAINS. SOME OF THESE STORMS PRODUCED WIND GUSTS IN EXCESS OF 35 MILES AN HOUR. A THUNDERSTORM ALSO PRODUCED A WIND GUST TO 51 MILES AN HOUR AT CODY EARLIER THIS AFTERNOON. SHOWERS AND THUNDERSTORMS WILL CONTINUE OVER THE STATE THROUGH MOST OF TONIGHT...ALTHOUGH THEY WILL DECREASE OVER THE SOUTHERN HALF OF THE STATE AFTER SUNSET. THESE STORMS ARE CAPABLE OF PRODUCING BRIEF HEAVY RAIN AND FREQUENT LIGHTNING. > MENTZER
Special weather statement, Jul 12, 5:00 PM MDT, 25 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE CHEYENNE WY 500 PM MDT WED JUL 12 1989 ...A FEW STRONG THUNDERSTORMS HAD DEVELOPED IN SOUTHWEST WYOMING AT 5 PM... WEATHER RADAR AND LIGHTNING STRIKE SENSORS SHOWED THAT THE STRONGEST STORMS WERE LOCATED NEAR THE TOWN OF GREEN RIVER AND SOUTH NEAR THE FLAMING GORGE RESERVOIR. THE STORMS WERE MOVING NORTH AT ABOUT 20 MILES AN HOUR. PEOPLE IN THE WESTERN PART OF SWEETWATER COUNTY...ESPECIALLY NEAR GREEN RIVER...SHOULD BE PREPARED FOR THUNDERSTORMS PRODUCING GUSTY WINDS...BRIEF HEAVY RAIN...DEADLY LIGHTNING...AND POSSIBLY SOME SMALL HAIL UNTIL 630 PM. DASELER
Nearby
Severe Thunderstorm Warnings in Wyoming, 1989Every severe thunderstorm warning in 1989
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.