Alert archive / Washington / Snow Squall Warnings in 2023

Snow Squall Warning 9, NWS Spokane, WA

February 21, 2023Spokane County, Washington

NWS Spokane, WA issued this snow squall warning at Feb 21, 2023, 5:27 PM PST for Spokane County, Washington. It was in force for 63 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 21, 2023, 5:27 PM PST (01:27 UTC)
Expired: Feb 21, 2023, 6:30 PM PST
In force: 63 min
Issued by: NWS Spokane, WA
Area: Storm-based polygon

County Spokane County, WA

The radar

The Spokane radar (KOTX), 18 km from the middle of the area, began a volume at 01:26 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.

The nearest sounding before it

Spokane, WA (KOTX), launched 00:00Z, 1.5 hours before the alert went out and 76 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: 775 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: 37 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

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 Spokane, WA wrote its last area forecast discussion before this snow squall warning went out at Feb 21, 3:46 PM PST, 1 hour 41 minutes earlier.

Area forecast discussion, Feb 21, 3:46 PM PST, 1 hour 41 minutes before

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In the hours before

Special weather statement, Feb 21, 11:58 AM PST, 5 hours 29 minutes before

Special Weather Statement
National Weather Service Spokane WA
1158 AM PST Tue Feb 21 2023

IDZ001-212100-
Northern Panhandle-
1158 AM PST Tue Feb 21 2023

...A SNOW SQUALL WILL AFFECT SOUTHWESTERN BONNER COUNTY...

At 1157 AM PST, a snow squall was located near Coolin and Sandpoint.
Movement was southwest at 10 mph.

Winds in excess of 30 mph are possible with this squall.

Locations impacted include...
Sandpoint, Ponderay, Kootenai, Dover, Schweitzer Mountain, Cocolalla
and Coolin.

This includes the following highways...
 U.S. Highway 95 in Idaho between mile markers 460 and 480.
 U.S. Highway 2 in Idaho between mile markers 14 and 28.

Use extra caution if you must travel into or through this snow
squall. Rapid changes in visibility and potentially slick roads are
expected.

Conditions can deteriorate rapidly in winter weather situations. Be
prepared for snow or ice covered roads. Slow down and allow extra
time when traveling.

LAT...LON 4831 11703 4802 11654 4823 11630 4851 11686
TIME...MOT...LOC 1957Z 026DEG 10KT 4845 11689 4820 11644

JW

Local storm report, Feb 21, 3:38 PM PST, 1 hour 49 minutes before

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Special weather statement, Feb 21, 4:06 PM PST, 1 hour 21 minutes before

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Local storm report, Feb 21, 4:57 PM PST, 30 minutes before

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The office that day

Everything else NWS Spokane, WA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Feb 21, 4:27 PM PST	Snow Squall Warning	OTX	Spokane, Stevens	63 min
Feb 21, 5:10 PM PST	Snow Squall Warning	OTX	Stevens	50 min
Feb 22, 4:59 AM PST	Wind Chill Advisory	OTX	Adams, Douglas, Ferry, Grant, Lincoln, Okanogan and 4 more	53 hr
Feb 21, 4:06 PM PST	Special Weather Statement	OTX	Kootenai	54 min

Nearby

Snow Squall Warnings in Washington, 2023 Every snow squall warning in 2023

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.