Alert archive / Montana / Severe Thunderstorm Warnings in 1989
Severe Thunderstorm Warning 3, NWS Missoula, MT
NWS Missoula, MT issued this severe thunderstorm warning at May 10, 1989, 12:49 PM MDT for Jefferson County, Lewis and Clark County, Montana. It was in force for 116 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
- May 10, 1989, 12:49 PM MDT (18:49 UTC)
- Expired
- May 10, 1989, 2:45 PM MDT
- In force
- 116 min
- Issued by
- NWS Missoula, MT
- Area
- Whole counties
The radar
The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| May 10, 12:52 PM MDT | Thunderstorm Wind 52 | Lewis And Clark, 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. Storm Data before 1996 records only tornadoes, thunderstorm wind and hail.
The nearest sounding before it
Great Falls, MT (KGTF), launched 12:00Z, 6.8 hours before the alert went out and 118 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1682 m above ground
- 0-6 km bulk shear
- 16 kt
- 0-1 km storm-relative helicity
- 95 m²/s²
- 0-3 km storm-relative helicity
- 92 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.
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.
In the hours before
Special weather statement, May 10, 12:48 PM MDT, 1 minute before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE MISSOULA, MT 1237 PM MDT WED MAY 10 1989 AT 1230 PM TODAY...MISSOULA WEATHER RADAR WAS DETECTING SOME LARGE THUNDERSTORMS FROM NORTH OF BUTTE TO NEAR HELENA IN SOUTHWEST MONTANA. THESE STORMS WERE MOVING TOWARD THE NE AT ABOUT 40 MILES AN HOURS. A NEW THUNDERSTORM WAS DETECTED IN THE WILDERNESS AREA JUST TO THE WEST OF THE SW TIP OF RAVALLII COUNTY IN IDAHO. THIS STORM WAS MOVING ALONG THE WEST SLOPES OF THE BITTERROOT MOUNTAINS. ADDITIONAL THUNDERSTORMS ARE EXPECTED TO DEVELOP AND THE CHANCE OF STRONG THUNDERSTORM WINDS AND HAIL EXISTS THIS AFTERNOON INTO TONIGHT. ADDITONAL STATEMENTS WILL BE ISSUED AS THUNDERSTORMS DEVELOP. PLEASE REPORT ANY DAMAGING WEATHER TO YOUR NEAREST LAW ENFORCEMENT AGENCY OR THE YOUR NEAREST NATIONAL WEATHER SERVICE OFFICE IF ANY IS DETECTED. END/LGH
The office that day
Everything else NWS Missoula, MT issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 9, 11:59 PM MDT | Severe Thunderstorm Warning | MSO | Missoula, Ravalli | 61 min |
| May 10, 12:03 PM MDT | Severe Thunderstorm Warning | MSO | Jefferson, Silver Bow | 57 min |
| May 10, 2:26 PM MDT | Severe Thunderstorm Warning | MSO | Missoula | 64 min |
Nearby
Severe Thunderstorm Warnings in Montana, 1989Every severe thunderstorm warning in 1989
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.