Alert archive / Montana / Severe Thunderstorm Warnings in 2011
Severe Thunderstorm Warning 4, NWS Missoula, MT
NWS Missoula, MT issued this severe thunderstorm warning at Jul 12, 2011, 2:25 PM MDT for Powell County, Montana. It was in force for 35 min. 1 report came from inside the area while it was in force.
The area
The outline as issued, with what was reported inside it.
The facts
- Issued
- Jul 12, 2011, 2:25 PM MDT (20:25 UTC)
- Expired
- Jul 12, 2011, 3:00 PM MDT
- In force
- 35 min
- Issued by
- NWS Missoula, MT
- Area
- Storm-based polygon
County Powell County, MT
The radar
The Missoula radar (KMSX), 102 km from the middle of the area, began a volume at 20:26 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 12, 2:45 PM MDT | HAIL 1 | 1 Nnw Brock Creek, MT | QUARTER SIZE HAIL COVERED THE GROUND. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The watch it was issued in
The SPC watch in force over the same counties when this warning went out.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Jul 12, 1:38 PM MDT | Severe Thunderstorm Watch | SPC | 7 hr |
The nearest sounding before it
Great_falls, MT (KTFX), launched 12:00Z, 8.4 hours before the alert went out and 184 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
- 1763 m above ground
- 0-6 km bulk shear
- 20 kt
- 0-1 km storm-relative helicity
- 105 m²/s²
- 0-3 km storm-relative helicity
- 107 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
183
WUUS55 KMSO 122025
SVRMSO
MTC077-122100-
/O.NEW.KMSO.SV.W.0004.110712T2025Z-110712T2100Z/
BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MISSOULA MT
225 PM MDT TUE JUL 12 2011
THE NATIONAL WEATHER SERVICE IN MISSOULA HAS ISSUED A
* SEVERE THUNDERSTORM WARNING FOR...
CENTRAL POWELL COUNTY IN WEST CENTRAL MONTANA...
* UNTIL 300 PM MDT.
* AT 221 PM MDT...DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM
CAPABLE OF PRODUCING LARGE DAMAGING HAIL UP TO GOLF BALL SIZE.
THIS STORM WAS LOCATED NEAR GARRISON...OR ABOUT 9 MILES NORTHWEST
OF DEER LODGE...AND WAS MOVING NORTH AT 25 MPH.
* LOCATIONS IMPACTED INCLUDE...BROCK CREEK...FINN...GARRISON AND
GOLDCREEK.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS AND HAIL...ALONG WITH
FREQUENT LIGHTNING AND HEAVY RAIN. FOR YOUR PROTECTION...GO INDOORS
AND STAY AWAY FROM WINDOWS. IF YOU ARE CAUGHT OUTSIDE...MOVE TO A
WELL PROTECTED AREA.
A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM MDT
TUESDAY EVENING FOR EAST CENTRAL IDAHO AND WEST CENTRAL MONTANA.
&&
LAT...LON 4639 11278 4646 11302 4688 11282 4687 11278
4684 11278 4684 11269 4679 11252 4673 11252
TIME...MOT...LOC 2026Z 202DEG 20KT 4652 11285
$$2 follow-up statements
029
WWUS55 KMSO 122045
SVSMSO
SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MISSOULA MT
245 PM MDT TUE JUL 12 2011
MTC077-122100-
/O.CON.KMSO.SV.W.0004.000000T0000Z-110712T2100Z/
POWELL MT-
245 PM MDT TUE JUL 12 2011
...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 300 PM MDT
FOR CENTRAL POWELL COUNTY...
* AT 240 PM MDT...DOPPLER RADAR CONTINUED TO INDICATE A SEVERE
THUNDERSTORM CAPABLE OF PRODUCING HAIL UP TO ONE INCH IN DIAMETER.
THIS STORM WAS LOCATED NEAR BROCK CREEK...OR ABOUT 14 MILES NORTH
OF DEER LODGE...AND WAS MOVING NORTH AT 25 MPH.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM MDT
TUESDAY EVENING FOR EAST CENTRAL IDAHO AND WEST CENTRAL MONTANA.
&&
LAT...LON 4639 11278 4646 11302 4688 11282 4687 11278
4684 11278 4684 11269 4679 11252 4673 11252
TIME...MOT...LOC 2045Z 202DEG 20KT 4662 11279
$$655
WWUS55 KMSO 122053
SVSMSO
SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MISSOULA MT
253 PM MDT TUE JUL 12 2011
MTC077-122102-
/O.EXP.KMSO.SV.W.0004.000000T0000Z-110712T2100Z/
POWELL MT-
253 PM MDT TUE JUL 12 2011
...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL POWELL COUNTY EXPIRES
AT 300 PM MDT...
THUNDERSTORMS WILL CONTINUE MOVE THROUGH THE AREA PRODUCING HEAVY
RAIN AND SOME SMALL HAIL.
A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM MDT
TUESDAY EVENING FOR EAST CENTRAL IDAHO AND WEST CENTRAL MONTANA.
LAT...LON 4639 11278 4646 11302 4688 11282 4687 11278
4684 11278 4684 11269 4679 11252 4673 11252
TIME...MOT...LOC 2052Z 202DEG 20KT 4666 11277
$$The office that day
Everything else NWS Missoula, MT issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 12, 4:27 PM MDT | Severe Thunderstorm Warning | MSO | Granite, Missoula | 48 min |
Nearby
Severe Thunderstorm Warnings in Montana, 2011Every severe thunderstorm warning in 2011
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.