Alert archive / Montana / Severe Thunderstorm Warnings in 1997
Severe Thunderstorm Warning 23, NWS Missoula, MT
NWS Missoula, MT issued this severe thunderstorm warning at Jul 21, 1997, 6:40 PM MDT for Lincoln County, Montana. It was in force for 65 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 21, 1997, 6:40 PM MDT (00:40 UTC)
- Expired
- Jul 21, 1997, 7:45 PM MDT
- In force
- 65 min
- Issued by
- NWS Missoula, MT
- Area
- Whole counties
County Lincoln County, MT
The radar
The Spokane radar (KOTX), 191 km from the middle of the area, began a volume at 00:40 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 21, 7:15 PM MDT | Thunderstorm Wind 70 | Libby, 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
Spokane, WA (KOTX), launched 00:00Z, 0.7 hours before the alert went out and 119 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
- 1102 J/kg
- Mixed-layer CIN
- -4 J/kg
- Mixed-layer LCL
- 2385 m above ground
- 0-6 km bulk shear
- 58 kt
- 0-1 km storm-relative helicity
- 156 m²/s²
- 0-3 km storm-relative helicity
- 200 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 5.8
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KMSO 220044 RRA SVRMSO MTC053-220145- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE MISSOULA MT 640 PM MDT MON JUL 21 1997 THE NATIONAL WEATHER SERVICE IN MISSOULA HAS ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 745 PM MDT FOR PEOPLE IN THE FOLLOWING LOCATION... IN NORTHWEST MONTANA ...SOUTHWEST LINCOLN COUNTY AT 640 PM MDT...MISSOULA DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM 25 MILES SOUTHWEST OF TROY MOVING TO THE NORTHEAST AT 20 MPH. THIS STORM WILL MOVE NORTH OF BULL LAKE AND CROSS STATE HIGHWAY 56 AROUND 715 PM MDT. RADAR INDICATES LARGE HAIL IS LIKELY WITH THIS STORM ALONG WITH THE POSSIBILITY OF WINDS IN EXCESS OF 55 MPH. FOR YOUR PROTECTION MOVE INDOORS IMMEDIATELY. FOSS / BELTZ
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 21, 1:46 PM MDT, 4 hours 54 minutes earlier.
Area forecast discussion, Jul 21, 1:46 PM MDT, 4 hours 54 minutes before
WESTERN MONTANA AND NORTH CENTRAL IDAHO FORECAST DISCUSSION NATIONAL WEATHER SERVICE MISSOULA MT 145 PM MDT MON JUL 21 1997 TSTMS BREAKING OUT EASTERN WASHINGTON ALONG THETA-E RIDGE THIS AFTERNOON WITH LIMITED MOISTURE TO THE WEST EXCEPT COASTAL AREAS. ETA TARGETS CONVECTIVE ACTIVITY STILL OVER NORTHERN PANHANDLE..EXTREME NORTHERN MONTANA AND GLACIER PARK INTO THIS EVENING AND LINGERING OVER DIVIDE DURING THE MORNING. WEAK FRONT MOVES THROUGH WESTERN MONTANA OVERNIGHT PRODUCING ISOLATED ACTIVITY. ON TUESDAY..STABILITY INCREASES ALONG WITH DRYING TREND AS SURFACE RIDGE BUILDS FROM THE WEST. SOUTHWEST ZONES STILL MAINTAIN ENOUGH INSTABILITY TO TRIGGER HIGH-BASED TSTMS. ALSO WILL MENTION LOCAL WEST WINDS AS AFTERNOON MIXING AND SURFACE GRADIENT TIGHTENS. GOING WITH MOS TREND TO COOL SLIGHT TUESDAY BUT WILL DIVERGE FROM MOS WEDNESDAY RETURNING TO WARMING TEMPERATURES. ON WEDNESDAY.. AVN ADVERTISES CONTINUED WESTERLY FLOW WITH ALL ENERGY WELL NORTH IN CANADA. ONE EXCEPTION BEING THE EXTREME SOUTHWEST WHERE MOONSONAL MOISTURE PUSH UP FROM THE SOUTH WITH SOME CONVECTION POSSIBLE. WILL MENTION TSTMS ZONE 8. STOLL LIB .. 058/085 051/087 ... 333210 FCA BU 056/083 049/085 048 33320Z0 POL .. 060/086 055/087 ... 332100 MSO BU 057/085 053/087 052 332100 HMM .. 054/088 051/090 ... 332100 BTM .. 052/083 049/084 ... 331211 S80 .. 059/083 059/083 ... 332000 P69 .. 063/087 063/087 ... 332100 SMN .. 055/090 055/090 ... 331100
The office that day
Everything else NWS Missoula, MT issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 21, 7:40 PM MDT | Severe Thunderstorm Warning | MSO | Lincoln | 65 min |
| Jul 21, 8:05 PM MDT | Severe Thunderstorm Warning | MSO | Flathead, Lake | 85 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.