Alert archive / Montana / Flash Flood Warnings in 2002
Flash Flood Warning 10, NWS Glasgow, MT
NWS Glasgow, MT issued this flash flood warning at Aug 21, 2002, 12:35 AM MDT for Valley County, Montana. It was in force for 6 hr. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- Aug 21, 2002, 12:35 AM MDT (06:35 UTC)
- Expired
- Aug 21, 2002, 6:30 AM MDT
- In force
- 6 hr
- Issued by
- NWS Glasgow, MT
- Area
- Whole counties
County Valley County, MT
The radar
The Glasgow radar (KGGW), 18 km from the middle of the area, began a volume at 06:38 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.
The nearest sounding before it
Glasgow Intl Airport, MT (KGGW), launched 00:00Z, 6.6 hours before the alert went out and 17 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
- 41 J/kg
- Mixed-layer CIN
- -403 J/kg
- Mixed-layer LCL
- 2487 m above ground
- 0-6 km bulk shear
- 51 kt
- 0-1 km storm-relative helicity
- 29 m²/s²
- 0-3 km storm-relative helicity
- 182 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000 WGUS55 KGGW 210635 FFWGGW MTC105-211230- BULLETIN - EAS ACTIVATION REQUESTED FLASH FLOOD WARNING NATIONAL WEATHER SERVICE GLASGOW MT 1234 AM MDT WED AUG 21 2002 THE NATIONAL WEATHER SERVICE IN GLASGOW HAS ISSUED A * FLASH FLOOD WARNING FOR... SOUTHERN VALLEY COUNTY IN NORTHEAST MONTANA * UNTIL 630 AM MDT * AT 1228 AM MDT...RADAR INDICATED THUNDERSTORMS WITH VERY HEAVY RAINFALL FROM 6 MILES NORTH OF GLASGOW TO 17 MILES WEST OF DUCK CREEK FISHING ACCESS SITE. THE THUNDERSTORMS WERE MOVING NORTHEAST AT 10 MPH. * SLOW MOVING THUNDERSTORMS ARE PRODUCING TORRENTIAL RAINFALL IN THE WARNED AREA. RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLASH FLOODING INCLUDE...GLASGOW AND DUCK CREEK FISHING ACCESS SITE BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE DANGERS OF FLOODS AND FLASH FLOODS. IF FLASH FLOODING IS OBSERVED ACT QUICKLY. MOVE UP TO HIGHER GROUND TO ESCAPE FLOOD WATERS. DO NOT STAY IN AREAS SUBJECT TO FLOODING WHEN WATER BEGINS RISING. .END 79
What 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.
NWS Glasgow, MT wrote its last area forecast discussion before this flash flood warning went out at Aug 20, 8:45 PM MDT, 3 hours 50 minutes earlier.
Area forecast discussion, Aug 20, 8:45 PM MDT, 3 hours 50 minutes before
NORTHEAST MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GLASGOW MT
845 PM MDT TUE AUG 20 2002
.SHORT TERM...
WILL INCREASE POPS TO SEVERAL WESTERN COUNTIES FOR TONIGHT.
THUNDERSTORM CLUSTER ROLLING EAST THROUGH CENTRAL MT BEING WATCHED THIS
EVENING. THIS AREA IS NOT MOVING ALL THAT FAST (ABOUT 20-25 MPH)...AND
AM NOT CONFIDENT THAT IT WILL MAKE MUCH HEADWAY EAST INTO NE MT
OVERNIGHT. WILL BUMP UP POPS OVER SOME OF THE WESTERN ZONES
(PHILLIPS/GARFIELD AND PETROLEUM) TO 40 PERCENT...BUT LEAVE 20 PERCENTS
FOR THE REMAINDER OF THE CWA. JAMBA
.LONG TERM...
MED RANGE MODELS IN SOME DISAGREEMENT ON SOLUTION THROUGH EXTENDED
PERIOD BUT GENERAL TREND IS TO DEVELOP OMEGA BLOCK TYPE PATTERN
WITH UPPER LOW OVER PACIFIC NORTHWEST AND RIDGE OVER CENTRAL CANADA.
WILL KEEP CHANCE POPS WITH PROXIMITY OF UPPER LOW AND DIFFLUENT
FLOW. EBERT
KGGW TBB 057/080 055/082 058/081 90243111
BBBB 051/081 050/084 051/081 052/083 9011333333
KGDV TBB 057/082 058/084 058/084 90243111
BBBB 052/082 050/083 050/082 051/084 9012333333
.GGW...NONE.The office that day
Everything else NWS Glasgow, MT issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 20, 11:23 PM MDT | Severe Thunderstorm Warning | GGW | Valley | 52 min |
| Aug 21, 12:18 AM MDT | Severe Thunderstorm Warning | GGW | Valley | 57 min |
| Aug 21, 1:19 AM MDT | Severe Thunderstorm Warning | GGW | Valley | 56 min |
| Aug 21, 2:19 AM MDT | Severe Thunderstorm Warning | GGW | McCone, Valley | 56 min |
| Aug 21, 2:44 AM MDT | Flash Flood Warning | GGW | McCone | 6 hr |
| Aug 21, 4:53 AM MDT | Severe Thunderstorm Warning | GGW | McCone | 67 min |
| Aug 21, 10:20 AM MDT | Flash Flood Warning | GGW | Valley | 6 hr |
Nearby
Flash Flood Warnings in Montana, 2002Every flash flood warning in 2002
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; radar from the NEXRAD Level II archive.