Alert archive / Montana / Flash Flood Warnings in 1998

Flash Flood Warning 1, NWS Missoula, MT

July 3, 1998Lake County, Missoula County, Sanders County, Montana

NWS Missoula, MT issued this flash flood warning at Jul 3, 1998, 4:34 PM MDT for Lake County, Missoula County, Sanders County, Montana. It was in force for 86 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, 4:34 PM MDT (22:34 UTC)
Expired: Jul 3, 1998, 6:00 PM MDT
In force: 86 min
Issued by: NWS Missoula, MT
Area: Whole counties

Counties Lake County, MT, Missoula County, MT, Sanders County, MT

The nearest sounding before it

Spokane, WA (KOTX), launched 12:00Z, 10.6 hours before the alert went out and 154 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: 963 m above ground
0-6 km bulk shear: 10 kt
0-1 km storm-relative helicity: -3 m²/s²
0-3 km storm-relative helicity: -22 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 
TTAA00 KMSO 032240 RRA
FFWMSO
MTC047-063-089-040000-

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

THE NATIONAL WEATHER SERVICE HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTHERN SANDERS COUNTY IN WEST CENTRAL MONTANA
  SOUTHERN LAKE COUNTY IN WEST CENTRAL MONTANA
  CENTRAL...NORTHERN AND EASTERN MISSOULA COUNTY IN WEST CENTRAL
  MONTANA

* UNTIL 600 PM MDT

* AT 430 PM MDT...RADAR /SPOTTERS INDICATED .90 INCHES OF RAIN IN
  MISSOULA IN 20 MINUTES.

* FLASH FLOODING CAN BE EXPECTED IN SOUTHERN SANDERS...NORTHERN
  AND EASTERN MISSOULA COUNTY BY 500 PM MDT

THIS STORM IS CAPABLE OF PRODUCING VERY HEAVY RAIN. INTERIOR ROOM
ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS. HEAVY RAINS FLOOD
ROADS QUICKLY AND CAN CAUSE RAPID RISES ON SMALL STREAM SO DO NOT
DRIVE INTO AREAS WHERE WATER COVERS THE ROAD.

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 Missoula, MT wrote its last area forecast discussion before this flash flood warning went out at Jul 3, 2:45 PM MDT, 1 hour 49 minutes earlier.

Area forecast discussion, Jul 3, 2:45 PM MDT, 1 hour 49 minutes before

WESTERN MONTANA AND NORTH CENTRAL IDAHO FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MISSOULA MT
245 PM MDT FRI JUL 3 1998

MODELS IN FAIRLY GOOD AGREEMENT WITH LOCATION OF MAIN VORT MAX
LOCATED NEAR THE WESTERN PORTION OF THE WASHINGTON-OREGON BORDER.
ETA BETTER WITH THE FINER DETAILS SUCH A LOCATION OF VORT MAX OVER
NORTHEASTERN WASHINGTON AND SOUTHERN OREGON. ACTIVITY WAS SLOW TO GET
GOING OVER WESTERN MONTANA AS DRIER AIR ALOFT MOVED IN FROM THE GREAT
BASIN THIS MORNING. CONVERGENCE ZONE OVER CENTRAL IDAHO FROM S80 TO
MULLAN PASS ATTM AND MOVING SLOWLY NORTH. WITH STRONG LOW LEVEL
CONVERGENCE ASSOCIATED WITH THERMAL TROF AND 850 LOW...LIS OF -4
TO -6 AND HIGH THETA-E VALUES A FEW SEVERE TSTMS HAD DEVELOPED OVER
CENTRAL IDAHO. SPOTTERS AT ELK CITY REPORTED HEAVY RAIN AND PEA SIZE
HAIL. SATELLITE SHOWING TSTM ACTIVITY SLOWLY MOVING EAST TOWARDS WEST
CENTRAL MONTANA ATTM SO NEED TO WATCH THIS AREA CLOSELY.  THE STORM
PREDICTION CENTER HAS ISSUED A SEVERE TSTM WATCH FOR MOST OF IDAHO
AND WESTERN MONTANA. TROF AXIS BECOMES MORE POSITIVE TILT AS IT
SLOWLY MOVES EAST ON SATURDAY PUSHING THE THERMAL TROF EAST OF THE
DIVIDE. TSTMS SHOULD DEVELOP AGAIN IN UNSTABLE AIR MASS ON
SATURDAY...BUT EXPECT TO BE LESS INTENSE. TROF WEAKENS SUNDAY BUT AVN
FORECASTS A STRONG SHORT WAVE TO MOVE INTO THE AREA SO LOOKS LIKE
ANOTHER ROUND OF TSTM ACTIVITY. HARMER

...FORECASTS BELOW ARE PRELIMINARY AND SUBJECT TO CHANGE...

LIB .. 060/078 056/076 ... 327535
FCA WE 058/078 054/075 052 327555
POL .. 060/072 056/068 ... 327545
MSO WE 057/079 054/075 053 327545
HMM .. 059/083 055/080 ... 327545
BTM .. 049/079 049/075 ... 324334
S80 .. 058/078 056/075 ... 328335
P69 .. 060/080 058/076 ... 328445
SMN .. 054/075 052/072 ... 325333

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 2, 6:10 PM MDT	Severe Thunderstorm Warning	MSO	Ravalli	45 min
Jul 3, 3:14 PM MDT	Severe Thunderstorm Warning	MSO	Mineral, Missoula	46 min
Jul 3, 3:39 PM MDT	Severe Thunderstorm Warning	MSO	Mineral, Missoula	61 min
Jul 3, 4:19 PM MDT	Severe Thunderstorm Warning	MSO	Lake, Missoula, Sanders	61 min
Jul 3, 5:20 PM MDT	Severe Thunderstorm Warning	MSO	Granite, Missoula, Powell	45 min

Nearby

Flash Flood Warnings in Montana, 1998 Every 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.