Alert archive / Montana / Flash Flood Warnings in 2001

Flash Flood Warning 1, NWS Glasgow, MT

July 12, 2001Garfield County, Montana

NWS Glasgow, MT issued this flash flood warning at Jul 12, 2001, 4:35 PM MDT for Garfield County, Montana. It was in force for 3 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 12, 2001, 4:35 PM MDT (22:35 UTC)
Expired
Jul 12, 2001, 7:30 PM MDT
In force
3 hr
Issued by
NWS Glasgow, MT
Area
Whole counties; the outline is the Mesonet’s reconstruction

County Garfield County, MT

The radar

The Billings radar (KBLX), 151 km from the middle of the area, began a volume at 22:39 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 12:00Z, 10.6 hours before the alert went out and 169 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-pSkew-T log-p diagram, Glasgow Intl Airport, MT at 12:00Z on 2001-07-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 32 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Glasgow Intl Airport, MT at 12:00Z on 2001-07-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -7 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
32 J/kg
Mixed-layer CIN
-371 J/kg
Mixed-layer LCL
1152 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
-7 m²/s²
0-3 km storm-relative helicity
15 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 122236
FFWGGW
MTC033-130130-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE GLASGOW MT
435 PM MDT THU JUL 12 2001

THE NATIONAL WEATHER SERVICE IN GLASGOW HAS ISSUED A

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

* UNTIL 730 PM MDT

* AT 426 PM MDT...WEATHER SERVICE DOPPLER RADAR INDICATED
  THUNDERSTORMS WITH VERY HEAVY RAINFALL 8 MILES NORTH OF EDWARDS...
  OR ABOUT 23 MILES WEST OF JORDAN...MOVING SOUTH AT 5 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...EDWARDS AND SAND SPRINGS

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.

LAT...LON 4731 10727 4726 10752 4586 10709 4599 10647

.END
91

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 12, 2:29 PM MDT, 2 hours 6 minutes earlier.

Area forecast discussion, Jul 12, 2:29 PM MDT, 2 hours 6 minutes before
NORTHEAST MONTANA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GLASGOW MT
229 PM MDT THU JUL 12 2001

THIS AFTERNOON A DEW POINT FRONT ACROSS CENTRAL MONTANA. DEW POINTS
ACROSS THE CWFA IN THE MID TO UPPER 60S. CONVECTION FIRING OVER
WESTERN MONTANA WITH A SHORTWAVE MOVING THROUGH THE WESTERN PART OF
THE STATE THIS AFTERNOON. THIS WAVE CONTINUES TO NNE A PIECE OF THIS
WAVE WILL MOVE ACROSS THE WESTERN AREAS THIS EVENING AND TONIGHT.

THIS EVENING...SHRA/TSRA SHOULD MOVING INTO THE REGION MAINLY OVER
THE WESTERN CWFA...ALREADY HAVING AFTERNOON POPCORN CONVECTION OVER
THE SOUTHERN CWFA WITH DAYTIME HEATING. SPC SWODY1 UPDATE PUTS THE
WESTERN ZONES IN A SLGT RISK FOR SVR. TIME HEIGHT SOUNDINGS SHOW A
BETTER SHEAR ENVIRONMENT FOR THIS EVENING ACROSS THE WEST...WET BULB
ZEROS ARE PRETTY HIGH FOR A SIGNIFICANT THREAT OF LARGE
HAIL...HOWEVER STRONG GUSTS CAN BE EXPECTED WITH LARGER STORMS...AND
MOST OF ALL VERY HEAVY RAINFALL. WILL HOLD UP ON A FLASH FLOOD WATCH
FOR THE EASTERN ZONES SINCE THE BEST CHANCE FOR TSRA REMAINS WEST
AND SOUTH.

AFTER THE CONVECTION MOVES OUT LATE THIS EVENING...DO EXPECT ANOTHER
ROUND OF LOWS ST/FG FOR THE EARLY MORNING HOURS FOR THE MISSOURI AND
MILK RIVER VALLEYS. WILL ADD AM FG TO THE ZONES. ETA TRIES TO KEEP
LOW CLOUDS IN ALL DAY ON FRIDAY...HOWEVER DO EXPECT WITH THIS TIME
OF YEAR THE CLOUDS WILL LIFT OUT WITH THE HEATING OF THE DAY.
LOOKING FOR MORE OF THE SAME WITH PM TSRA AGAIN.  SAME PATTERN FOR
SATURDAY CONTINUES.

FOR TEMPS...GOING TO STAY WITH THE STATUS QUO...MODELS ARE TRYING TO
COOL DOWN THE TEMPS SOME ON SATURDAY...HOWEVER NOT BUYING INTO THAT
YET...WILL KEEP THEM UP.                    PROTON

EXTENDED...MODELS SUGGEST AN OMEGA BLOCK DEVELOPING OVER NORTH
AMERICA DURING THE EXTENDED PERIOD. THE UPPER LEVEL RIDGE IS
FORECAST TO REMAIN EAST OF MONTANA WITH A DEEP TROUGH ALONG THE WEST
COAST AND AN UPPER LOW OVER SOUTHWEST CANADA. THIS PATTERN KEEPS
NORTHEAST MONTANA IN SOUTHWEST FLOW ALOFT FOR THE ENTIRE PERIOD.
WILL CONTINUE WITH CHANCE POPS EACH DAY WITH TEMPERATURES REMAINING
NEAR NORMAL.  WATERHOUSE

KGGW 064/088 062/088 062/088 061/087 060/086 060/086 059/085
     TTTTTTT  943232/9933333
KGDV 064/090 064/092 063/090 062/089 061/088 060/087 059/086
     TTTTTTT  943232/9933333

.GGW...NONE.

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 12, 4:04 PM MDTSevere Thunderstorm WarningGGWGarfield56 min
Jul 12, 4:52 PM MDTSevere Thunderstorm WarningGGWGarfield53 min
Jul 12, 5:18 PM MDTTornado WarningGGWGarfield57 min

Nearby

Flash Flood Warnings in Montana, 2001Every 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.