Alert archive / Montana / Severe Thunderstorm Warnings in 1997
Severe Thunderstorm Warning 20, NWS Missoula, MT
NWS Missoula, MT issued this severe thunderstorm warning at Jul 19, 1997, 2:19 PM MDT for Beaverhead County, Montana. It was in force for 56 min. 1 report came from inside the area while it was in force.
The area
The counties it named, with what was reported inside it.
The facts
- Issued
- Jul 19, 1997, 2:19 PM MDT (20:19 UTC)
- Expired
- Jul 19, 1997, 3:15 PM MDT
- In force
- 56 min
- Issued by
- NWS Missoula, MT
- Area
- Whole counties
County Beaverhead County, MT
The radar
The Pocatello radar (KSFX), 226 km from the middle of the area, began a volume at 20:20 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
| Time | Report | Where | Remark |
|---|---|---|---|
| Jul 19, 2:45 PM MDT | Tornado F0 | Dillon, MT |
NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.
The nearest sounding before it
Great_falls, MT (KTFX), launched 12:00Z, 8.3 hours before the alert went out and 313 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.
- Mixed-layer CAPE
- 122 J/kg
- Mixed-layer CIN
- -92 J/kg
- Mixed-layer LCL
- 1225 m above ground
- 0-6 km bulk shear
- 17 kt
- 0-1 km storm-relative helicity
- 44 m²/s²
- 0-3 km storm-relative helicity
- 51 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KMSO 192027 RRA SVRMSO MTC001-192115- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM AND FLASH FLOOD WARNING NATIONAL WEATHER SERVICE MISSOULA MT 219 PM MDT SAT JUL 19 1997 THE NATIONAL WEATHER SERVICE IN MISSOULA HAS ISSUED A SEVERE THUNDERSTORM AND FLASH FLOOD WARNING EFFECTIVE UNTIL 315 PM MDT FOR PEOPLE IN THE FOLLOWING LOCATION... IN SOUTHWEST MONTANA ...CENTRAL BEAVERHEAD COUNTY AT 2:15 PM MDT MISSOULA DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM 10 MILES SOUTHWEST OF DILLION MT. THE STORM WAS MOVING SLOWLY TO THE NORTHEAST AT 5 MILES AN HOUR. PROLONGED HEAVY RAINFALL FROM THE SLOW MOVING STORM COULD CAUSE HYDROPLA NAND POOR DRIVING VISIBILITIES FOR MOTORISTS ON INTERSTATE 15 AND NEARBY AREAS. STANDING WATER MAY COVER LOW LYING AREAS. THESE SEVERE THUNDERSTORMS PRODUCE DESTRUCTIVE HAIL...DEADLY LIGHTNING..AND VERY HEAVY RAIN. FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS. HEAVY RAINS FLOOD ROADS QUICKLY DON'T DRIVE INTO AREAS WHERE WATER COVERS THE ROAD. BROCK/FOSS
What forecasters said that day
The local office's own words before this severe thunderstorm 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 severe thunderstorm warning went out at Jul 19, 1:51 PM MDT, 28 minutes earlier.
Area forecast discussion, Jul 19, 1:51 PM MDT, 28 minutes before
WESTERN MONTANA AND NORTH CENTRAL IDAHO FORECAST DISCUSSION NATIONAL WEATHER SERVICE MISSOULA MT 145 PM MDT SAT JUL 19 1997 WE GOT OUR OWN LITTLE VERSION OF HURRICANE DANNY OVER THE NORTHERN ROCKIES THIS AFTERNOON. LARGE AREAS OF MODERATE TO HEAVY SHOWERS AND HAIL-PRODUCING THUNDERSTORMS ROTATING AROUND LOW CENTER. NEW MODELS DID NOT VERIFY WELL ON POSITION OF LOW CENTER...THEY WERE ALL TOO FAR SOUTH. LOW APPEARS TO BE WAFFLING WESTWARD INTO NORTH CENTRAL IDAHO. MODELS PROGRESS LOW VERY LITTLE THROUGH MIDDAY SUNDAY...THEN MOVE IT TO THE EAST SUNDAY AFTERNOON. HARD TO KNOW WHAT TO BELIEVE IN THIS CUTOFF SITUATION. WILL KEEP EARLY-PERIOD POPS UP...AND THEN SLOWLY DRY THINGS SUNDAY NIGHT INTO MONDAY. I KEPT IT FAIRLY CLOSE TO MOS GUIDANCE. NOT SURE WHETHER MOISTURE BANDS WILL MAKE IT DEEP INTO NORTHWEST MONTANA...SO WILL SIT ON THE FENCE THERE. SHOULD BE ANOTHER ACTIVELY CONVECTIVE DAY AGAIN SUNDAY. WHITMORE ...FORECASTS BELOW ARE PRELIMINARY AND SUBJECT TO CHANGE... LIB .. 057/079 057/084 ... 344442 FCA WE 056/077 056/082 053 345542 POL .. 057/077 057/084 ... 346542 MSO WE 056/076 056/085 053 347532 HMM .. 055/079 055/085 ... 347532 BTM .. 050/075 050/0r78 ... 347532 S80 .. 055/084 055/088 ... 344321 P69 .. 058/083 058/087 ... 345321 SMN .. 053/082 053/086 ... 346432
The office that day
Everything else NWS Missoula, MT issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 19, 8:30 AM MDT | Severe Thunderstorm Warning | MSO | Beaverhead, Silver Bow | 60 min |
| Jul 19, 9:34 AM MDT | Severe Thunderstorm Warning | MSO | Deer Lodge | 56 min |
| Jul 19, 12:00 PM MDT | Severe Thunderstorm Warning | MSO | Powell | 45 min |
| Jul 19, 2:19 PM MDT | Flash Flood Warning | MSO | Beaverhead | 56 min |
| Jul 19, 3:06 PM MDT | Tornado Warning | MSO | Beaverhead | 69 min |
| Jul 19, 4:00 PM MDT | Severe Thunderstorm Warning | MSO | Silver Bow | 60 min |
| Jul 19, 5:25 PM MDT | Severe Thunderstorm Warning | MSO | Powell | 50 min |
Nearby
Severe Thunderstorm Warnings in Montana, 1997Every severe thunderstorm warning in 1997
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.