Alert archive / Montana / Flash Flood Warnings in 2002

Flash Flood Warning 4, NWS Great Falls, MT

August 29, 2002Lewis and Clark County, Montana

NWS Great Falls, MT issued this flash flood warning at Aug 29, 2002, 6:17 PM MDT for Lewis and Clark County, Montana. It was in force for 118 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Aug 29, 2002, 6:17 PM MDT (00:17 UTC)
Expired: Aug 29, 2002, 8:15 PM MDT
In force: 118 min
Issued by: NWS Great Falls, MT
Area: Counties, with a storm outline in the text

County Lewis and Clark County, MT

The radar

The Great Falls radar (KTFX), 90 km from the middle of the area, began a volume at 00:17 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

Great_falls, MT (KTFX), launched 00:00Z, 0.3 hours before the alert went out and 126 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: 350 J/kg
Mixed-layer CIN: -60 J/kg
Mixed-layer LCL: 2846 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: 22 m²/s²
0-3 km storm-relative helicity: 103 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.4

Open this sounding in Storm Lab

The text

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

000 
WGUS55 KTFX 300017
FFWTFX
MTC049-300215-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE GREAT FALLS MT
615 PM MDT THU AUG 29 2002

THE NATIONAL WEATHER SERVICE IN GREAT FALLS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  THE CAVE GULCH BURN AREA ON THE NORTHEAST SIDE OF CANYON FERRY RESERVOIR

* UNTIL 815 PM MDT

* AT 612 PM MDT...WEATHER SERVICE DOPPLER RADAR INDICATED VERY HEAVY
  RAIN OVER SOUTHEASTERN LEWIS AND CLARK COUNTY...OR ABOUT 12        
  MILES NORTHEAST OF HELENA...MOVING EAST AT 20 MPH. ANOTHER AREA OF 
  HEAVY RAIN WAS BETWEEN WINSTON AND TOWNSEND MOVING NORTHEAST AT 20 
  MPH.

* THE THUNDERSTORMS WITH HEAVY RAINFALL WILL BE NEAR... 
  THE CAVE GULCH BURN AREA BY 630 PM.

THE HEAVY RAINS OVER THE BURNED AREA FROM THE FIRES OF 2000 WILL 
CAUSE DEBRIS FLOWS AND FLASH FLOODING ON THE NORTHEAST SIDE OF 
CANYON FERRY RESERVOIR.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY.
RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE
PRECAUTIONS TO PROTECT LIFE AND PROPERTY. DO NOT ATTEMPT TO CROSS
SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR BY
AUTOMOBILE. IF YOUR VEHICLE STALLS, ABANDON IT IMMEDIATELY AND SEEK
HIGHER GROUND.

TO REPORT SEVERE WEATHER HAVE THE NEAREST LAW ENFORCEMENT AGENCY
RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST OFFICE IN
GREAT FALLS.

LAT...LON 4668 11200 4658 11173 4675 11168 4689 11185

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 30, 4:20 PM MDT	Severe Thunderstorm Warning	TFX	Glacier	55 min
Aug 30, 5:15 PM MDT	Severe Thunderstorm Warning	TFX	Glacier, Pondera, Toole	60 min

Nearby

Flash Flood Warnings in Montana, 2002 Every 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.