Alert archive / Montana / Snow Squall Warnings in 2020

Snow Squall Warning 5, NWS Great Falls, MT

February 23, 2020Lewis and Clark County, Montana

NWS Great Falls, MT issued this snow squall warning at Feb 23, 2020, 6:23 PM MST for Lewis and Clark County, Montana. It was in force for 67 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
Feb 23, 2020, 6:23 PM MST (01:23 UTC)
Expired
Feb 23, 2020, 7:30 PM MST
In force
67 min
Issued by
NWS Great Falls, MT
Area
Storm-based polygon

County Lewis and Clark County, MT

The radar

The Great Falls radar (KTFX), 85 km from the middle of the area, began a volume at 01:23 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 00:00Z, 1.4 hours before the alert went out and 140 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-pSkew-T log-p diagram, Great_falls, MT at 00:00Z on 2020-02-24Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Great_falls, MT at 00:00Z on 2020-02-24The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 25 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
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
1 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1966 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
25 m²/s²
0-3 km storm-relative helicity
39 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The office that day

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

IssuedProductOfficeCountiesLasted
Feb 23, 6:07 PM MSTSpecial Weather StatementTFXBeaverhead23 min
Feb 23, 6:35 PM MSTSpecial Weather StatementTFXBeaverhead25 min
Feb 23, 6:45 PM MSTSnow Squall WarningTFXBroadwater, Jefferson, Meagher30 min
Feb 23, 7:10 PM MSTSpecial Weather StatementTFXBeaverhead, Broadwater, Cascade, Jefferson, Meagher50 min
Feb 23, 7:17 PM MSTSpecial Weather StatementTFXBroadwater28 min
Feb 23, 7:47 PM MSTSpecial Weather StatementTFXBroadwater, Cascade, Gallatin, Judith Basin, Madison, Meagher43 min
Feb 23, 8:35 PM MSTSpecial Weather StatementTFXFergus, Gallatin, Judith Basin, Madison, Meagher40 min
Feb 24, 4:28 PM MSTSpecial Weather StatementTFXCascade62 min

Nearby

Snow Squall Warnings in Montana, 2020Every snow squall warning in 2020

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.