Alert archive / Montana / Flash Flood Warnings in 1990
Flash Flood Warning 5, NWS Great Falls, MT
NWS Great Falls, MT issued this flash flood warning at Aug 20, 1990, 5:13 PM MDT for Cascade County, Chouteau County, Judith Basin County, Montana. It was in force for 62 min.
The area
The counties it named.
The facts
- Issued
- Aug 20, 1990, 5:13 PM MDT (23:13 UTC)
- Expired
- Aug 20, 1990, 6:15 PM MDT
- In force
- 62 min
- Issued by
- NWS Great Falls, MT
- Area
- Whole counties
Counties Cascade County, MT, Chouteau County, MT, Judith Basin County, MT
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
Great_falls, MT (KTFX), launched 12:00Z, 11.2 hours before the alert went out and 8 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
- 3639 m above ground
- 0-6 km bulk shear
- 25 kt
- 0-1 km storm-relative helicity
- 80 m²/s²
- 0-3 km storm-relative helicity
- 97 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 KGTF 202314 FFWGTF MTC013-015-045-210015- BULLETIN - EBS ACTIVATION REQUESTED FLASH FLOOD WARNING NATIONAL WEATHER SERVICE GREAT FALLS MT 513 PM MDT MON AUG 20 1990 THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A FLASH FLOOD WARNING EFFECTIVE UNTIL 615 PM MDT FOR PEOPLE IN THE FOLLOWING LOCATION...S... IN NORTH CENTRAL MONTANA ...NORTHEASTERN CASCADE COUNTY...SOUTHWESTERN CHOUTEAU COUNTY ...NORTHERN JUDITH BASIN COUNTY VERY HEAVY RAIN HAS BEEN REPORTED AT BELT MONTANA WHICH HAS BROUGHT TRAFFIC TO A STANDSTILL. RADAR SHOWS A BAND OF VERY STRONG THUNDERSTORMS STRETCHING FROM CENTRAL CASCADE COUNTY SOUTHWEST TO WESTERN JUDITH BASIN COUNTY. THESE THUNDERSTORMS CONTAIN VERY HEAVY RAIN AND ARE MOVING NORTH AT 25 MILES AN HOUR. PERSONS IN THE WARNING AREA SHOULD BE ALERT TO SMALL STREAM F AS WELL AS FLOODING OF STREETS AND ROADWAYS. THIS WARNING ESPECIALLY INCLUDES THE HIGHWOOD MOUNTAINS. GROUND IS ALREADY SATURATED SO THE HEAVY RAIN WILL CAUSE A LOT OF RUNOFF. STREAMS MAY RISE QUICKLY. A SEVERE THUNDERSTORM WARNING CONTINUES IN EFFECT FOR EASTERN CASCADE COUNTY UNTIL 530 PM. HAIL ONE INCH IN DIAMETER WAS REPORTED AT BELT. DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS SAFELY. VEHICLES CAUGHT IN RISING WATER SHOULD BE ABANDONED QUICKLY. MOVE TO HIGHER GROUND. 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 WAdTER MOVE UP TO HIGHER GROUND.
The office that day
Everything else NWS Great Falls, MT issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 19, 8:36 PM MDT | Flash Flood Warning | TFX | Fergus, Judith Basin | 2 hr |
| Aug 19, 8:36 PM MDT | Flash Flood Warning | TFX | Teton | 2 hr |
| Aug 19, 8:36 PM MDT | Flash Flood Warning | TFX | Cascade | 69 min |
| Aug 20, 4:27 PM MDT | Severe Thunderstorm Warning | TFX | Cascade | 63 min |
| Aug 20, 4:30 PM MDT | Severe Thunderstorm Warning | TFX | Cascade | 60 min |
Nearby
Flash Flood Warnings in Montana, 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.