Alert archive / Montana / Severe Thunderstorm Warnings in 1999
Severe Thunderstorm Warning 13, NWS Missoula, MT
NWS Missoula, MT issued this severe thunderstorm warning at Jul 17, 1999, 5:35 PM MDT for Missoula County, Montana. It was in force for 25 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 17, 1999, 5:35 PM MDT (23:35 UTC)
- Expired
- Jul 17, 1999, 6:00 PM MDT
- In force
- 25 min
- Issued by
- NWS Missoula, MT
- Area
- Whole counties
County Missoula County, MT
The nearest sounding before it
Spokane, WA (KOTX), launched 12:00Z, 11.6 hours before the alert went out and 201 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
- 1766 m above ground
- 0-6 km bulk shear
- 58 kt
- 0-1 km storm-relative helicity
- 34 m²/s²
- 0-3 km storm-relative helicity
- 191 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 172337 RRA SVRMSO MTC063-180000- BULLETIN - EAS ACTIVATION REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE MISSOULA MT 535 PM MDT SAT JUL 17 1999 THE NATIONAL WEATHER SERVICE IN MISSOULA HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... EAST CENTRAL MISSOULA COUNTY IN WEST CENTRAL MONTANA * UNTIL 600 PM MDT * AT 535 PM MDT...RADAR INDICATED A SEVERE THUNDERSTORM 7 MILES NORTHWEST OF CLEARWATER JUNCTION...OR 29 MILES NORTHEAST OF MISSOULA... MOVING NORTH AT 30 MPH. * THE SEVERE THUNDERSTORM WILL BE... OVER SEELEY LAKE AT 545 PM MDT SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND AND HAIL ALONG WITH FREQUENT LIGHTNING AND VERY HEAVY RAIN. FOR YOUR PROTECTION...STAY INDOORS AWAY FROM WINDOWS.
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 17, 2:05 PM MDT, 3 hours 30 minutes earlier.
Area forecast discussion, Jul 17, 2:05 PM MDT, 3 hours 30 minutes before
WESTERN MONTANA AND NORTH CENTRAL IDAHO FORECAST DISCUSSION NATIONAL WEATHER SERVICE MISSOULA MT 205 PM MDT SAT JUL 17 1999 ISOLATED SHOWERS AND THUNDERSTORMS DEVELOPING ACROSS THE SOUTHERN PORTION OF CWA THIS AFTERNOON WITH CONVECTION EXPECTED TO INCREASE LATER THIS AFTERNOON. AIR MASS QUITE UNSTABLE WITH STRONG DYNAMICS SHIFTING NORTHWARD ACROSS THE CWA TONIGHT. THE UPPER LOW SYSTEM WILL OPEN UP INTO A TROUGH WITH A STRONG VORT MAX SWINGING INTO THE NORTHERN PORTION OF THE CWA TONIGHT. WILL KEEP THUNDERSTORMS GOING OVERNIGHT NORTH...WHILE THUNDERSTORMS LIKELY TO DIMINISH THIS EVENING FARTHER SOUTH. MOS POP GUIDANCE PRETTY HIGH...AND PREFER SCATTERED POPS TO HANDLE ACTIVITY TONIGHT. AIR MASS TO REMAIN SOMEWHAT UNSTABLE WITH RESIDUAL MOISTURE AND DYNAMICS HANGING ON NEAR THE CANADIAN BORDER SUNDAY...UNDER A WEAK UPPER TROUGH. ELSEWHERE...A MORE ANTICYCLONIC FLOW ALOFT WITH SHORT WAVE RIDGING TO TAKE PLACE AHEAD OF A CLOSED LOW SYSTEM DEVELOPING OFF THE NORTHERN CALIFORNIA COAST. WILL TAKE ALL MENTION OF POPS OUT OF THE SOUTHERN ZONE FORECAST SUNDAY. MONDAY LOOKS LIKE A DRY...WARMER DAY UNDER A SHORT WAVE RIDGE WITH A SOUTHERN FLOW ALOFT. HOWEVER...SOME MID LEVEL MOISTURE ORIGINATING FROM THE CLOSED LOW OFF THE NORTHERN CALIFORNIA COAST MAY CREEP UP INTO THE EXTREME SOUTH PART OF CWA LATE. WILL MENTION A SLIGHT CHANCE OF LATE DAY THUNDERSTORMS IN LEMHI COUNTY AND BUTTE AREAS MONDAY. JOHNSON EXTENDED...SOUTHWEST FLOW CONTINUES OVER CWFA THROUGH THE PERIOD. MEDIUM RANGE MODELS NOT CONSISTENT FROM RUN TO RUN IN DEALING WITH WAVES EJECTING OUT OF MAIN WEST COAST TROUGH. EVEN THOUGH GENERAL UPPER FLOW REMAINS ANTICYCLONIC...PERIODIC WEAK WAVE ENERGY THROUGH OUR AREA IS PROBABLE. SO APPEARS TO BE POTENTIAL FOR ISOLATED LATE DAY THUNDERSTORMS EACH DAY. WHITMORE
Nearby
Severe Thunderstorm Warnings in Montana, 1999Every severe thunderstorm warning in 1999
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.