Alert archive / Montana / Flash Flood Warnings in 2011

Flash Flood Warning 2, NWS Great Falls, MT

June 6, 2011Cascade County, Montana

NWS Great Falls, MT issued this flash flood warning at Jun 6, 2011, 7:41 PM MDT for Cascade County, Montana. It was in force for 6 hr. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Jun 6, 2011, 7:41 PM MDT (01:41 UTC)
Expired
Jun 7, 2011, 1:45 AM MDT
In force
6 hr
Issued by
NWS Great Falls, MT
Area
Storm-based polygon
Flood severity
None

County Cascade County, MT

The radar

The Great Falls radar (KTFX), 40 km from the middle of the area, began a volume at 01:41 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.

What was reported inside it

TimeReportWhereRemark
Jun 6, 7:44 PM MDTFLASH FLOOD8 Nnw Monarch, MTCASCADE COUNTY FIRE HAVE CLOSED HIGHWAY 89 AT MILE MARKER 11 DUE TO FLOODING.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Great_falls, MT (KTFX), launched 00:00Z, 1.7 hours before the alert went out and 33 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, Great_falls, MT at 00:00Z on 2011-06-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 386 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Great_falls, MT at 00:00Z on 2011-06-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 72 square meters per square second.1939587897Sfc1 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
386 J/kg
Mixed-layer CIN
-53 J/kg
Mixed-layer LCL
1661 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
72 m²/s²
0-3 km storm-relative helicity
277 m²/s²
Significant tornado parameter
0.1
Supercell composite
5.0

Open this sounding in Storm Lab

The text

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

536 
WGUS55 KTFX 070141
FFWTFX
MTC013-070745-
/O.NEW.KTFX.FF.W.0002.110607T0141Z-110607T0745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
741 PM MDT MON JUN 6 2011

THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  EAST CENTRAL CASCADE COUNTY IN CENTRAL MONTANA...

* UNTIL 145 AM MDT TUESDAY

* AT 731 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  FLASH FLOODING FROM A THUNDERSTORM OVER THE WARNED AREA.

* LOCATIONS IN THE WARNING INCLUDE BELT.

ESTIMATED RAINFALL AMOUNTS OF 2 TO 3 INCHES HAVE ALREADY FALLEN JUST 
SOUTH OF BELT AND EAST OF RAYNESFORD WITH AN ADDITIONAL 1 TO 2 
INCHES POSSIBLE OVER THE NEXT FEW HOURS.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO BELT

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...COUNTRY ROADS...AS WELL AS FARMLAND ALONG THE
BANKS OF CREEKS AND STREAMS.

&&

LAT...LON 4745 11102 4741 11079 4700 11079 4704 11102

$$

SCHOTT
2 follow-up statements
200 
WGUS55 KTFX 070144 CCA
FFWTFX
MTC013-070745-
/O.COR.KTFX.FF.W.0002.110607T0141Z-110607T0745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING...CORRECTED
NATIONAL WEATHER SERVICE GREAT FALLS MT
741 PM MDT MON JUN 6 2011

THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  EAST CENTRAL CASCADE COUNTY IN CENTRAL MONTANA...

* UNTIL 145 AM MDT TUESDAY

* AT 731 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  FLASH FLOODING FROM A THUNDERSTORM OVER THE WARNED AREA.

* LOCATIONS IN THE WARNING INCLUDE BELT.

ESTIMATED RAINFALL AMOUNTS OF 2 TO 3 INCHES HAVE ALREADY FALLEN JUST 
SOUTH OF BELT AND WEST OF RAYNESFORD WITH AN ADDITIONAL 1 TO 2 
INCHES POSSIBLE OVER THE NEXT FEW HOURS.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO BELT

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...COUNTRY ROADS...AS WELL AS FARMLAND ALONG THE
BANKS OF CREEKS AND STREAMS.

&&

LAT...LON 4745 11102 4741 11079 4700 11079 4704 11102

$$

SCHOTT
968 
WGUS75 KTFX 070739
FFSTFX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE GREAT FALLS MT
139 AM MDT TUE JUN 7 2011

MTC013-070746-
/O.EXP.KTFX.FF.W.0002.000000T0000Z-110607T0745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CASCADE MT-
139 AM MDT TUE JUN 7 2011

...THE FLASH FLOOD WARNING WILL EXPIRE AT 145 AM MDT FOR EAST CENTRAL
CASCADE COUNTY...

THE AREA OF VERY HEAVY RAINFALL OVER EAST CENTRAL CASCADE COUNTY HAS 
MOVED OFF TO THE NORTHEAST AND THE THREAT FOR FLASH FLOODING HAS 
DIMINISHED. HOWEVER...ADDITIONAL RAINFALL IS EXPECTED LATER TONIGHT 
THROUGH TOMORROW AND AREA CREEKS AND STREAMS WILL REMAIN VERY HIGH 
WITH SMALL STREAM FLOODING POSSIBLE...HOWEVER RAPID RISES ARE NO 
LONGER ANTICIPATED.   

LAT...LON 4745 11102 4741 11079 4700 11079 4704 11102

$$

HOENISCH

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 6, 6:13 PM MDTSevere Thunderstorm WarningTFXCascade, Teton47 min
Jun 6, 6:44 PM MDTSevere Thunderstorm WarningTFXCascade, Chouteau, Judith Basin46 min
Jun 6, 7:59 PM MDTSevere Thunderstorm WarningTFXCascade, Judith Basin, Meagher46 min
Jun 6, 11:04 PM MDTRiver Flood WarningTFXCascade10 days
Jun 7, 12:48 AM MDTRiver Flood WatchTFX25 hr
Jun 7, 6:02 AM MDTAreal Flood WarningTFXGlacier, Pondera, Teton10 days
Jun 7, 2:41 PM MDTAreal Flood WarningTFXJefferson, Lewis and Clark15 days
Jun 7, 3:45 PM MDTRiver Flood WarningTFXLewis and Clark4 days
Jun 7, 3:45 PM MDTRiver Flood WarningTFXToole10 days
Jun 7, 5:01 PM MDTRiver Flood WarningTFXGallatin31 days

Nearby

Flash Flood Warnings in Montana, 2011Every flash flood warning in 2011

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.