Alert archive / Wyoming / Flash Flood Warnings in 1990
Flash Flood Warning 1, NWS Riverton, WY
NWS Riverton, WY issued this flash flood warning at Aug 11, 1990, 1:37 PM MDT for Park County, Wyoming. It was in force for 53 min.
The area
The counties it named.
The facts
- Issued
- Aug 11, 1990, 1:37 PM MDT (19:37 UTC)
- Expired
- Aug 11, 1990, 2:30 PM MDT
- In force
- 53 min
- Issued by
- NWS Riverton, WY
- Area
- Whole counties
County Park County, WY
The radar
The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.
The nearest sounding before it
Lander/Hunt Fiel, WY (KLND), launched 12:00Z, 7.6 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
- 4 J/kg
- Mixed-layer CIN
- -251 J/kg
- Mixed-layer LCL
- 1783 m above ground
- 0-6 km bulk shear
- 16 kt
- 0-1 km storm-relative helicity
- 28 m²/s²
- 0-3 km storm-relative helicity
- 93 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 111937
FFWLND
WYC029-112045-
BULLETIN - EBS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LANDER WY
137 PM MDT SAT AUG 11 1990
THE NATIONAL WEATHER SERVICE IN LANDER HAS ISSUED A
FLASH FLOOD WARNING EFFECTIVE UNTIL 245 PM MDT
FOR PEOPLE IN THE FOLLOWING COUNTY...
IN NORTHWEST WYOMING
...WEST CENTRAL PARK
AT 130 PM A THUNDERSTORM WITH HEAVY RAIN PRODUCED A MUD SLIDE ACROSS
BOTH LANES OF HIGHWAY 20 IN THE NORTH FORK CANYON...ABOUT 25 MILES
WEST OF CODY. HAIL AND FREQUENT LIGHTNING WAS ALSO REPORTED WITH THIS
STORM. THE STORM WAS MOVING TO THE EAST AT 20 MILES AN HOUR.
CAMPERS ALONG THE NORTH FORK OF THE SHOSHONE RIVER SHOULD WATCH FOR
RAPIDLY RISING WATER. ADDITIONAL MUD SLIDES IN THE NORTH FORK CANYON
ARE POSSIBLE AS THIS SOTRM MOVES EAST TOWARD CODY.
A FLASH FLOOD WARNING MEANS THAT FLOODING IS OCCURRING OR IS
IMMINENT. MOST FLASH FLOOD DEATHS OCCUR IN AUTOMOBILES. DO NOT
ATTEMPT TO CROSS BRIDGES...DIPS...OR LOW SPOTS IF WATER COVERS
THE ROADWAY. NEVER TRY TO CROSS A FLOWING STREAM...EVEN A SMALL
ONE...ON FOOT. TO ESCAPE RISING WATER MOVE UP TO HIGHER GROUND.
BUSHWhat forecasters said that day
The local office's own words before this flash flood 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 11, 12:51 PM MDT, 46 minutes before
WYZ001-002-112045 SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE LANDER WY 1250 PM MDT SAT AUG 11 1990 ...THUNDERSTORMS WERE INCREASING OVER NORTHWEST WYOMING... AT 1245 PM RADAR SHOWED THUNDERSTORMS INCREASING ACROSS NORTHWEST WYOMING...INCLUDING YELLOWSTONE NATIONAL PARK. A STRONG THUNDERSTORM WAS LOCATED 30 MILES WEST OF CODY...NEAR PAHASKA TEPEE AT THE HEAD OF THE NORTH FORK CANYON. THE THUNDERSTORM WAS MOVING TO THE EAST AROUND 25 MILES AN HOUR. IT SHOULD BE IN THE CODY AREA BETWEEN 130 AND 2 PM. HEAVY RAIN...HAIL...GUSTY WINDS AND FREQUENT LIGHTNING ACCOMPANIED THIS STORM AS IT MOVED THROUGH YELLOWSTONE PARK. PERSON IN THE NORTH FORK CANYON WEST OF CODY SHOULD WATCH FOR THIS STORM. BE PREPARED TO TAKE SHELTER IF THREATENING WEATHER APPROACHES. SMALL STREAMS AND RIVERS CAN RISE RAPIDLY FROM HEAVY DOWNPOORS ASSOCIATED WITH THUNDERSTORMS. BUSH
Nearby
Flash Flood Warnings in Wyoming, 1990Every flash flood warning in 1990
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.