Alert archive / Montana / Flash Flood Warnings in 1998

Flash Flood Warning 2, NWS Missoula, MT

July 3, 1998Missoula County, Powell County, Montana

NWS Missoula, MT issued this flash flood warning at Jul 3, 1998, 6:12 PM MDT for Missoula County, Powell County, Montana. It was in force for 53 min. 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 3, 1998, 6:12 PM MDT (00:12 UTC)
Expired
Jul 3, 1998, 7:05 PM MDT
In force
53 min
Issued by
NWS Missoula, MT
Area
Whole counties

Counties Missoula County, MT, Powell County, MT

The nearest sounding before it

Great_falls, MT (KTFX), launched 00:00Z, 0.2 hours before the alert went out and 221 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 1998-07-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1560 joules per kilogram.LCLEL10008507005003002001001 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, Great_falls, MT at 00:00Z on 1998-07-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 58 square meters per square second.19395878Sfc1 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
1560 J/kg
Mixed-layer CIN
-2 J/kg
Mixed-layer LCL
1121 m above ground
0-6 km bulk shear
49 kt
0-1 km storm-relative helicity
58 m²/s²
0-3 km storm-relative helicity
310 m²/s²
Significant tornado parameter
1.9
Supercell composite
8.8

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KMSO 040015
FFWMSO
MTC063-077-040105-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE MISSOULA MT
612 PM MDT FRI JUL 3 1998

THE NATIONAL WEATHER SERVICE HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  EASTERN MISSOULA COUNTY IN WEST CENTRAL MONTANA
  CENTRAL POWELL COUNTY IN WEST CENTRAL MONTANA

* UNTIL 705 PM MDT

* AT 600 PM MDT...RADAR INICATED FLASH FLOOD ACROSS PORTIONS OF
  EASTER MISSOULA COUNTY AND CENTRAL POWELL COUNTY. RADAR RAIN
  FALL INDICATING 0.75 TO 1.00 INCHES OF RAINFALL IN ONE HOUR.

* FLASH FLOODING CAN BE EXPECTED NEAR THE JUNCTION OF HIGHWAY 200
  AND 83...OVANDO AND HELMSVILLE UNTIL 700 PM MDT.

HEAVY RAINS CAN FLOOD ROADS QUICKLY AND CAN CAUSE RAPID RISES ON
SMALL STREAMS. SO DO NOT DRIVE IINTO AREAS WHERE WATER COVERS THE
ROAD.

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 3, 6:21 PM MDTSevere Thunderstorm WarningMSODeer Lodge, Powell49 min
Jul 3, 8:32 PM MDTSevere Thunderstorm WarningMSOPowell33 min

Nearby

Flash Flood Warnings in Montana, 1998Every flash flood warning in 1998

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.