Alert archive / Idaho / Snow Squall Warnings in 2022

Snow Squall Warning 11, NWS Missoula, MT

November 27, 2022Idaho County, Idaho

NWS Missoula, MT issued this snow squall warning at Nov 27, 2022, 12:58 PM PST for Idaho County, Idaho. It was in force for 47 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: Nov 27, 2022, 12:58 PM PST (20:58 UTC)
Expired: Nov 27, 2022, 1:45 PM PST
In force: 47 min
Issued by: NWS Missoula, MT
Area: Storm-based polygon
Damage threat: Significant

County Idaho County, ID

The radar

The Missoula radar (KMSX), 175 km from the middle of the area, began a volume at 21:00 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.

The nearest sounding before it

Great_falls, MT (KTFX), launched 12:00Z, 9.0 hours before the alert went out and 413 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.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1679 m above ground
0-6 km bulk shear: 40 kt
0-1 km storm-relative helicity: 230 m²/s²
0-3 km storm-relative helicity: 270 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this snow squall 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 snow squall warning went out at Nov 27, 4:27 AM PST, 8 hours 31 minutes earlier.

Area forecast discussion, Nov 27, 4:27 AM PST, 8 hours 31 minutes before

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In the hours before

Local storm report, Nov 27, 9:00 AM PST, 3 hours 58 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MISSOULA MT
1000 AM MST SUN NOV 27 2022

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0958 AM     SNOW             6 SSW EUREKA            48.80N 115.11W
11/27/2022  E4.0 INCH        LINCOLN            MT   TRAINED SPOTTER

            ESTIMATE OF 4 TO 5 INCHES NEW SNOW.

&&

JK

Local storm report, Nov 27, 9:46 AM PST, 3 hours 12 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MISSOULA MT
1046 AM MST SUN NOV 27 2022

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0800 AM     SNOW             YAAK                    48.83N 115.71W
11/27/2022  M3.4 INCH        LINCOLN            MT   COCORAHS

            COCORAHS STATION MT-LN-6 YAAK.

&&

Special weather statement, Nov 27, 12:41 PM PST, 17 minutes before

Special Weather Statement
National Weather Service Missoula MT
141 PM MST Sun Nov 27 2022

MTZ004>006-043-272130-
Bitterroot/Sapphire Mountains MT-Missoula/Bitterroot Valleys MT-
Lower Clark Fork Region MT-Potomac/Seeley Lake Region MT-
141 PM MST Sun Nov 27 2022

...An intense snow shower will impact portions of south central
Missoula County through 230 PM MST...

At 140 PM MST, Doppler radar was tracking an intense snow shower over
Missoula, moving east at 25 mph.

HAZARD...Visibility one-half mile or less and winds in excess of 30
         mph.

SOURCE...Radar indicated.

IMPACT...Low visibility could result in dangerous driving
         conditions. Gusty winds could knock down tree limbs and
         blow around unsecured objects.

Locations impacted include...
Missoula, Lolo, Bonner-West Riverside, Wye, East Missoula,
Frenchtown, Evaro and Turah.

This includes the following highways...
 Interstate 90 near mile marker 81, and between mile markers 85 and
115.
 Highway 93 N between mile markers 0 and 8.
 Highway 93 S between mile markers 83 and 94.
 Highway 200 E between mile markers 0 and 5.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 4702 11438 4707 11404 4683 11365 4676 11411
TIME...MOT...LOC 2040Z 285DEG 22KT 4690 11399

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...30 MPH

The office that day

Everything else NWS Missoula, MT issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Nov 27, 12:23 PM PST	Snow Squall Warning	MSO	Flathead	67 min
Nov 27, 12:41 PM PST	Special Weather Statement	MSO	Missoula	49 min
Nov 27, 1:09 PM PST	Special Weather Statement	MSO	Powell	51 min
Nov 27, 2:06 PM PST	Snow Squall Warning	MSO	Deer Lodge, Granite	54 min
Nov 27, 2:14 PM PST	Snow Squall Warning Significant damage threat	MSO	Powell	61 min
Nov 27, 2:38 PM PST	Snow Squall Warning Significant damage threat	MSO	Deer Lodge, Powell	67 min
Nov 27, 3:00 PM PST	Snow Squall Warning Significant damage threat	MSO	Deer Lodge, Powell, Silver Bow	60 min
Nov 27, 3:17 PM PST	Snow Squall Warning	MSO	Ravalli	58 min
Nov 27, 3:32 PM PST	Snow Squall Warning Significant damage threat	MSO	Deer Lodge, Silver Bow	58 min

Nearby

Snow Squall Warnings in Idaho, 2022 Every snow squall warning in 2022

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; radar from the NEXRAD Level II archive.