Alert archive / Washington / Freeze Warnings in 2021

Freeze Warning 1, NWS Spokane, WA

May 18, 20219 counties in Washington; Bonner County, Boundary County, Kootenai County, Idaho

NWS Spokane, WA issued this freeze warning at May 18, 2021, 2:41 AM PDT for 9 counties in Washington; Bonner County, Boundary County, Kootenai County, Idaho. It took effect at May 19, 2021, 1:00 AM PDT. It was in force for 7 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
May 18, 2021, 2:41 AM PDT (09:41 UTC)
In effect from
May 19, 2021, 1:00 AM PDT
Expired
May 19, 2021, 8:00 AM PDT
In force
7 hr
Issued by
NWS Spokane, WA

Counties Bonner County, ID, Boundary County, ID, Kootenai County, ID, Adams County, WA, Douglas County, WA, Ferry County, WA, Grant County, WA, Lincoln County, WA, Okanogan County, WA, Pend Oreille County, WA, Spokane County, WA, Stevens County, WA

The radar

The Spokane radar (KOTX), 47 km from the middle of the area, began a volume at 09:41 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, 9.7 hours before the alert went out and 128 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, Spokane, WA at 00:00Z on 2021-05-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Spokane, WA at 00:00Z on 2021-05-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 26 square meters per square second.19395878Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2809 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
26 m²/s²
0-3 km storm-relative helicity
76 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

559 
WWUS76 KOTX 180941
NPWOTX

URGENT - WEATHER MESSAGE
National Weather Service Spokane WA
241 AM PDT Tue May 18 2021

IDZ001-WAZ036>038-042-182330-
/O.NEW.KOTX.FZ.W.0001.210519T0800Z-210519T1500Z/
Northern Panhandle-Spokane Area-Northeast Mountains-Okanogan
Highlands-East Slopes Northern Cascades-
Including the cities of Chewelah, Cheney, Rathdrum, Republic,
Eastport, Conconully, Colville, Bonners Ferry, Stehekin, Kettle
Falls, Rockford, Spokane, Sandpoint, Wauconda, Leavenworth,
Newport, Mazama, Davenport, Priest River, Winthrop, Twisp, Deer
Park, and Inchelium
241 AM PDT Tue May 18 2021

...FREEZE WARNING IN EFFECT FROM 1 AM TO 8 AM PDT WEDNESDAY...

* WHAT...Sub-freezing temperatures as low as 27 expected.

* WHERE...Chewelah, Cheney, Tyler, Chattaroy, Republic, Curlew, 
  Colville, Ione, Metaline Falls, Usk, Diamond Lake, Newport, Priest 
  River, Priest Lake, Plain, Winthrop, Twisp, Mazama, Deer Park, 
  Clayton and Loon Lake.

* WHEN...From 1 AM to 8 AM PDT Wednesday.

* IMPACTS...Frost and freeze conditions could kill crops and other 
  sensitive vegetation.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold.

&&

$$

LN
2 follow-up statements
754 
WWUS76 KOTX 181906
NPWOTX

URGENT - WEATHER MESSAGE
National Weather Service Spokane WA
1206 PM PDT Tue May 18 2021

WAZ035-191500-
/O.EXA.KOTX.FZ.W.0001.210519T0800Z-210519T1500Z/
Upper Columbia Basin-
Including the cities of Grand Coulee, Coulee City, Wilbur,
Ritzville, and Odessa
1206 PM PDT Tue May 18 2021

...FREEZE WARNING IN EFFECT FROM 1 AM TO 8 AM PDT WEDNESDAY UPPER 
COLUMBIA BASIN...

* WHAT...Sub-freezing temperatures as low as 29 expected for Upper 
  Columbia Basin.

* WHERE...Wilbur, Creston, Wilson Creek, Odessa, and Sprague.

* WHEN...From 1 AM to 8 AM PDT Wednesday.

* IMPACTS...Frost and freeze conditions could damage or kill 
  sensitive plants.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold.

&&

$$

IDZ001-WAZ036>038-042-191500-
/O.CON.KOTX.FZ.W.0001.210519T0800Z-210519T1500Z/
Northern Panhandle-Spokane Area-Northeast Mountains-Okanogan
Highlands-East Slopes Northern Cascades-
Including the cities of Chewelah, Cheney, Rathdrum, Republic,
Eastport, Conconully, Colville, Bonners Ferry, Stehekin, Kettle
Falls, Rockford, Spokane, Sandpoint, Wauconda, Leavenworth,
Newport, Mazama, Davenport, Priest River, Winthrop, Twisp, Deer
Park, and Inchelium
1206 PM PDT Tue May 18 2021

...FREEZE WARNING REMAINS IN EFFECT FROM 1 AM TO 8 AM PDT 
WEDNESDAY...

* WHAT...Sub-freezing temperatures as low as 26 expected.

* WHERE...Chewelah, Cheney, Tyler, Chattaroy, Republic, Curlew, 
  Colville, Ione, Metaline Falls, Usk, Diamond Lake, Newport, Priest 
  River, Priest Lake, Plain, Winthrop, Twisp, Mazama, Deer Park, 
  Clayton, and Loon Lake.

* WHEN...From 1 AM to 8 AM PDT Wednesday.

* IMPACTS...Frost and freeze conditions could damage or kill 
  sensitive plants.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold.

&&

$$

OTX
326 
WWUS76 KOTX 191500
NPWOTX

URGENT - WEATHER MESSAGE
National Weather Service Spokane WA
800 AM PDT Wed May 19 2021

IDZ001-WAZ035>038-042-191600-
/O.EXP.KOTX.FZ.W.0001.000000T0000Z-210519T1500Z/
Northern Panhandle-Upper Columbia Basin-Spokane Area-Northeast
Mountains-Okanogan Highlands-East Slopes Northern Cascades-
Including the cities of Chewelah, Cheney, Rathdrum, Republic,
Wilbur, Eastport, Conconully, Colville, Bonners Ferry, Stehekin,
Odessa, Kettle Falls, Rockford, Coulee City, Spokane, Sandpoint,
Wauconda, Leavenworth, Newport, Mazama, Davenport, Priest River,
Grand Coulee, Winthrop, Twisp, Deer Park, Ritzville, and
Inchelium
800 AM PDT Wed May 19 2021

...FREEZE WARNING HAS EXPIRED...

Temperatures this morning dipped below freezing across the northern 
Washington valleys and the valleys east of the Cascades. As of 8 am 
PDT most locations have warmed well above freezing and therefore the 
threat for freezing temperatures is over.

$$

OTX

Nearby

Freeze Warnings in Washington, 2021Freeze Warnings in Idaho, 2021Every freeze warning in 2021

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.