Alert archive / Montana / Flash Flood Warnings in 2001

Flash Flood Warning 33, NWS Glasgow, MT

July 31, 2001Dawson County, Prairie County, Wibaux County, Montana

NWS Glasgow, MT issued this flash flood warning at Jul 31, 2001, 2:02 AM MDT for Dawson County, Prairie County, Wibaux 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 outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties.

The facts

Issued: Jul 31, 2001, 2:02 AM MDT (08:02 UTC)
Expired: Jul 31, 2001, 8:00 AM MDT
In force: 6 hr
Issued by: NWS Glasgow, MT
Area: Whole counties; the outline is the Mesonet’s reconstruction

Counties Dawson County, MT, Prairie County, MT, Wibaux County, MT

The radar

The Glasgow radar (KGGW), 159 km from the middle of the area, began a volume at 08:06 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, 8.0 hours before the alert went out and 159 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 2238 m above ground
0-6 km bulk shear: 62 kt
0-1 km storm-relative helicity: -55 m²/s²
0-3 km storm-relative helicity: 142 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

000 
WGUS55 KGGW 310805
FFWGGW
MTC021-079-109-311400-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE GLASGOW MT
202 AM MDT TUE JUL 31 2001

THE NATIONAL WEATHER SERVICE IN GLASGOW HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  DAWSON COUNTY IN NORTHEAST MONTANA
  PRAIRIE COUNTY IN NORTHEAST MONTANA
  WIBAUX COUNTY IN NORTHEAST MONTANA

* UNTIL 800 AM MDT

* AT 200 AM MDT...WEATHER SERVICE DOPPLER RADAR INDICATED
  THUNDERSTORMS WITH VERY HEAVY RAINFALL OVER DAWSON...PRAIRIE AND
  WIBAUX COUNTIES...MOVING NORTHEAST 15 TO 20 MPH.

* SLOW MOVING THUNDERSTORMS ARE PRODUCING TORRENTIAL RAINFALL IN 
  THE WARNED AREA. RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE    
  FLASH FLOODING TO OCCUR.

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.

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.

LAT...LON 4715 10606 4691 10607 4686 10561 4664 10543
          4659 10517 4672 10455 4671 10414 4736 10407
          4737 10455 4759 10464 4758 10489 4768 10529
          4715 10541 4714 10576 4708 10581 4708 10598

.END
99

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 30, 8:35 PM MDT, 5 hours 27 minutes earlier.

Area forecast discussion, Jul 30, 8:35 PM MDT, 5 hours 27 minutes before

NORTHEAST MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GLASGOW MT
835 PM MDT MON JUL 30 2001

NO UPDATE.

CURRENT PACKAGE HAS SUFFICIENT MENTION OF SHOWERS FOR TONIGHT.
SHOWERS ARE MOSTLY CONFINED AT THIS TIME TO THE MOUNTAIN REGIONS OF
WESTERN MONTANA.  HOWEVER SOME SHOWERS AND MID-LEVEL VIRGA ARE
BECOMING VISIBLE OUT THE WINDOW.  MCNULTY

EXTENDED...RIDGE REMAINS EAST OF THE CWFA FOR THE EARLY PART OF THE
EXTENDED. FRIDAY THROUGH SUNDAY SOUTHWEST FLOW CONTINUES ACROSS THE
REGION WITH CHANCES OF TSRA. MONDAY THE EASTERN RIDGE BEGINS TO
SHIFT WEST OVER THE REGION. TEMPS WILL RUN WELL ABOVE NORMAL
THURSDAY AND FRIDAY...THEN A SFC FRONT ROLLS THROUGH ON SATURDAY FOR
A COOLER SATURDAY AND SUNDAY. MONDAY WITH THE RIDGE BUILDING IN AND
HEIGHTS IN TO THE 590DM RANGE...TEMPS SHOULD CLIMB BACK INTO THE
90S.  PROTON

KGGW 058/066 051/083 062/091 064/094 058/086 057/084 058/092
      WUUTTTB  764720/9413332
KGDV 058/069 052/084 061/091 064/095 058/088 058/084 059/093
      WUUTTTB  765720/9413332

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 31, 1:43 AM MDT	Severe Thunderstorm Warning	GGW	Prairie	62 min
Jul 31, 1:46 AM MDT	Severe Thunderstorm Warning	GGW	Dawson	59 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; radar from the NEXRAD Level II archive.