Alert archive / Washington / Frost Advisories in 2021

Frost Advisory 4, NWS Spokane, WA

October 7, 2021Adams County, Grant County, Washington

NWS Spokane, WA issued this frost advisory at Oct 7, 2021, 2:27 AM PDT for Adams County, Grant County, Washington. It took effect at Oct 8, 2021, 4:00 AM PDT. It was in force for 5 hr.

The area

The counties it named.

The facts

Issued
Oct 7, 2021, 2:27 AM PDT (09:27 UTC)
In effect from
Oct 8, 2021, 4:00 AM PDT
Expired
Oct 8, 2021, 9:00 AM PDT
In force
5 hr
Issued by
NWS Spokane, WA

Counties Adams County, WA, Grant County, WA

The radar

The Spokane radar (KOTX), 123 km from the middle of the area, began a volume at 09:26 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, 9.5 hours before the alert went out and 207 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 2021-10-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1 joules per kilogram.LCLEL10008507005003002001001 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 2021-10-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 80 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
1750 m above ground
0-6 km bulk shear
74 kt
0-1 km storm-relative helicity
80 m²/s²
0-3 km storm-relative helicity
30 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

050 
WWUS76 KOTX 070927
NPWOTX

URGENT - WEATHER MESSAGE
National Weather Service Spokane WA
227 AM PDT Thu Oct 7 2021

WAZ034-071730-
/O.NEW.KOTX.FR.Y.0004.211008T1100Z-211008T1600Z/
Moses Lake Area-
Including the cities of Ephrata, Moses Lake, Othello, Quincy, and
Winchester
227 AM PDT Thu Oct 7 2021

...FROST ADVISORY IN EFFECT FROM 4 AM TO 9 AM PDT FRIDAY...

* WHAT...Temperatures as low as 32 will result in frost formation.

* WHERE...Ephrata, Moses Lake, Othello, Quincy, and Winchester.

* WHEN...From 4 AM to 9 AM PDT Friday.

* IMPACTS...Frost could harm sensitive outdoor vegetation. Sensitive 
  outdoor plants may be killed if left uncovered.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold.

&&

$$
3 follow-up statements
047 
WWUS76 KOTX 071720
NPWOTX

URGENT - WEATHER MESSAGE
National Weather Service Spokane WA
1020 AM PDT Thu Oct 7 2021

WAZ034-081400-
/O.CON.KOTX.FR.Y.0004.211008T1100Z-211008T1600Z/
Moses Lake Area-
Including the cities of Ephrata, Moses Lake, Othello, Quincy, and
Winchester
1020 AM PDT Thu Oct 7 2021

...FROST ADVISORY REMAINS IN EFFECT FROM 4 AM TO 9 AM PDT FRIDAY...

* WHAT...Temperatures as low as 33 will result in frost formation.

* WHERE...Ephrata, Moses Lake, Othello, Quincy, and Winchester.

* WHEN...From 4 AM to 9 AM PDT Friday.

* IMPACTS...Frost could harm sensitive outdoor vegetation. Sensitive 
  outdoor plants may be killed if left uncovered.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold.

&&

$$

CD
496 
WWUS76 KOTX 081328
NPWOTX

URGENT - WEATHER MESSAGE
National Weather Service Spokane WA
628 AM PDT Fri Oct 8 2021

WAZ034-081600-
/O.CON.KOTX.FR.Y.0004.000000T0000Z-211008T1600Z/
Moses Lake Area-
Including the cities of Ephrata, Moses Lake, Othello, Quincy, and
Winchester
628 AM PDT Fri Oct 8 2021

...FROST ADVISORY REMAINS IN EFFECT UNTIL 9 AM PDT THIS MORNING...

* WHAT...Temperatures as low as 33 will result in frost formation.

* WHERE...Ephrata, Moses Lake, Othello, Quincy, and Winchester.

* WHEN...Until 9 AM PDT this morning.

* IMPACTS...Frost could harm sensitive outdoor vegetation. Sensitive 
  outdoor plants may be killed if left uncovered.

$$

JCLEV
189 
WWUS76 KOTX 081556
NPWOTX

URGENT - WEATHER MESSAGE
National Weather Service Spokane WA
856 AM PDT Fri Oct 8 2021

WAZ034-081700-
/O.EXP.KOTX.FR.Y.0004.000000T0000Z-211008T1600Z/
Moses Lake Area-
Including the cities of Ephrata, Moses Lake, Othello, Quincy, and
Winchester
856 AM PDT Fri Oct 8 2021

...FROST ADVISORY WILL EXPIRE AT 9 AM PDT THIS MORNING...

Early morning temperatures are warming above freezing and frost 
conditions as of mid morning. Since we've now seen a few days of 
near or freezing temperatures, the trend will continue that the 
region will see occasional freezing temperatures overnight going 
into the week ahead. Freezing and frost like temperatures will be 
more common going through the Fall season.

$$

CD

Nearby

Frost Advisories in Washington, 2021Every frost advisory 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.