Alert archive / Montana / Flash Flood Warnings in 2001

Flash Flood Warning 32, NWS Glasgow, MT

July 26, 2001Garfield County, Montana

NWS Glasgow, MT issued this flash flood warning at Jul 26, 2001, 12:39 PM MDT for Garfield 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: Jul 26, 2001, 12:39 PM MDT (18:39 UTC)
Expired: Jul 26, 2001, 6:45 PM MDT
In force: 6 hr
Issued by: NWS Glasgow, MT
Area: Whole counties

County Garfield County, MT

The nearest sounding before it

Glasgow Intl Airport, MT (KGGW), launched 12:00Z, 6.7 hours before the alert went out and 109 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.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 59 J/kg
Mixed-layer CIN: -213 J/kg
Mixed-layer LCL: 1424 m above ground
0-6 km bulk shear: 27 kt
0-1 km storm-relative helicity: -38 m²/s²
0-3 km storm-relative helicity: 49 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.7

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WGUS55 KGGW 261839
FFWGGW
MTC033-270045-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE GLASGOW MT
1239 PM MDT THU JUL 26 2001

THE NATIONAL WEATHER SERVICE IN GLASGOW HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  EASTERN GARFIELD COUNTY IN NORTHEAST MONTANA

* UNTIL 645 PM MDT

* AT 1235 PM MDT...WEATHER SERVICE DOPPLER RADAR INDICATED
  THUNDERSTORMS WITH VERY HEAVY RAINFALL 20 MILES EAST OF COHAGEN...
  OR ABOUT 34 MILES SOUTHWEST OF CIRCLE...MOVING NORTHEAST AT 15 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...RURAL EASTERN GARFIELD COUNTY

EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLASH FLOODING OF SMALL 
CREEKS AND STREAMS...COUNTRY ROADS...NORMALLY DRY WASHES AND 
COULEES...AS WELL AS FARMLAND ALONG THE BANKS OF CREEKS AND STREAMS.

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.

.END
95

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 Jul 26, 9:00 AM MDT, 3 hours 39 minutes earlier.

Area forecast discussion, Jul 26, 9:00 AM MDT, 3 hours 39 minutes before

NORTHEAST MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GLASGOW MT
900 AM MDT THU JUL 26 2001

STRONG THUNDERSTORM COMPLEX IN OUR SW ZONES HAS BEEN SEVERE THIS
MORNING WITH 1 INCH DIAMETER HAIL 15 MILES S OF GRASSRANGE.

THE INDUCING UPPER FEATURE WILL BE THE MAIN FOCUS FOR THE CWA TODAY...
AND IS SEEN NICELY ON THE MESO-ETA. THE ATMOS IS PRIMED OVER THE CWA
TODAY WITH CAPES ALREADY OVER 1000 J/KG AND LI/S NEAR -5 IN MY SE
ZONES. ZONES ALREADY MENTION POSSIBILITY OF SEVERE STORMS OVER THIS
AREA FOR TODAY...SO WILL LEAVE ALONE. REST OF FORECAST LOOKS GOOD.
JAMBA

EXTENDED...MODELS IN GOOD AGREEMENT THROUGH THE PERIOD. UPPER LEVEL
TROUGH DIGS IN OVER THE PACIFIC NORTHWEST PLACING THE REGION IN
SOUTHWEST FLOW ALOFT SATURDAY. SHOULD POSSIBLY SEE SOME SEVERE
CONVECTION AS SURFACE FRONT COLLIDES WITH DEWPOINTS IN THE 60S LATE
SATURDAY NIGHT. AVN SHOWING BEST OMEGA FOR OUR CWA ALONG THE
CANADIAN BORDER. SUNDAY...WILL SEE SLIGHTLY COOLER TEMPS AS TROUGH
SLIDES NORTHEAST...THEN GRADUAL WARMING TREND THROUGH THE PERIOD.
SOUTHWEST FLOW ALOFT CONTINUES AS TROUGH BECOMES ELONGATED WITH THE
DEVELOPMENT OF A CUTOFF LOW OFF THE COAST OF OREGON...SO WILL KEEP
CHANCE OF TS THROUGH THE REST OF THE FORECAST PERIOD. GILCHRIST/EBERT

KGGW /084 057/087 063/089 056/081 055/082 054/082 056/083
      BBTTTTT  90332/9763333
KGDV /083 062/086 063/088 057/080 055/082 054/082 056/081
      TBTTTTT  90442/9763333

The office that day

Everything else NWS Glasgow, MT issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 25, 6:08 PM MDT	Severe Thunderstorm Warning	GGW	Prairie	67 min
Jul 25, 6:46 PM MDT	Severe Thunderstorm Warning	GGW	Wibaux	59 min
Jul 26, 10:13 AM MDT	Severe Thunderstorm Warning	GGW	Phillips	62 min
Jul 26, 10:30 AM MDT	Severe Thunderstorm Warning	GGW	Garfield	60 min
Jul 26, 11:13 AM MDT	Severe Thunderstorm Warning	GGW	Valley	62 min
Jul 26, 2:12 PM MDT	Severe Thunderstorm Warning	GGW	Garfield	63 min
Jul 26, 3:15 PM MDT	Severe Thunderstorm Warning	GGW	Garfield	60 min
Jul 26, 4:15 PM MDT	Severe Thunderstorm Warning	GGW	Garfield	60 min
Jul 26, 5:55 PM MDT	Severe Thunderstorm Warning	GGW	Wibaux	65 min

Nearby

Flash Flood Warnings in Montana, 2001 Every flash flood warning in 2001

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.