Alert archive / California / Freeze Watches in 2021

Freeze Watch 2, NWS Eureka, CA

March 15, 2021Del Norte County, Humboldt County, Mendocino County, California

NWS Eureka, CA issued this freeze watch at Mar 15, 2021, 3:21 AM PDT for Del Norte County, Humboldt County, Mendocino County, California. It took effect at Mar 16, 2021, 12:00 AM PDT. It was in force for .

The area

The counties it named.

The facts

Issued
Mar 15, 2021, 3:21 AM PDT (10:21 UTC)
In effect from
Mar 16, 2021, 12:00 AM PDT
Expired
Mar 15, 2021, 1:38 PM PDT
In force
Issued by
NWS Eureka, CA

Counties Del Norte County, CA, Humboldt County, CA, Mendocino County, CA

The radar

The Eureka (Bunker Hill) radar (KBHX), 47 km from the middle of the area, began a volume at 10:22 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

Medford/Jackson, OR (KMFR), launched 00:00Z, 10.4 hours before the alert went out and 210 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, Medford/Jackson, OR at 00:00Z on 2021-03-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 4 joules per kilogram.LCLLFCEL10008507005003002001001 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, Medford/Jackson, OR at 00:00Z on 2021-03-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -10 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
4 J/kg
Mixed-layer CIN
-4 J/kg
Mixed-layer LCL
632 m above ground
0-6 km bulk shear
61 kt
0-1 km storm-relative helicity
-10 m²/s²
0-3 km storm-relative helicity
167 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

792 
WWUS76 KEKA 151021
NPWEKA

URGENT - WEATHER MESSAGE
National Weather Service Eureka CA
321 AM PDT Mon Mar 15 2021

CAZ110-111-114-152200-
/O.NEW.KEKA.HZ.A.0002.210316T0700Z-210316T1600Z/
Northwestern Mendocino Interior-Northeastern Mendocino Interior-
Northern Lake County-
321 AM PDT Mon Mar 15 2021

...HARD FREEZE WATCH IN EFFECT FROM LATE TONIGHT THROUGH TUESDAY
MORNING...

* WHAT...Sub-freezing temperatures as low as 24 possible.

* WHERE...Northwestern Mendocino Interior, Northeastern Mendocino
  Interior and Northern Lake County.

* WHEN...From late tonight through Tuesday morning.

* IMPACTS...Frost and freeze conditions could kill crops, other
  sensitive vegetation and possibly damage unprotected outdoor
  plumbing.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold. To prevent
freezing and possible bursting of outdoor water pipes they should
be wrapped, drained, or allowed to drip slowly. Those that have
in-ground sprinkler systems should drain them and cover above-
ground pipes to protect them from freezing.

Frost Advisories and Freeze Warnings are issued during the local
growing season as defined by climatology and local agriculture
experts. Once the growing season has ended these statements will
no longer be issued until the spring.

&&

$$

CAZ101-103-104-112-113-115-152200-
/O.NEW.KEKA.FZ.A.0002.210316T0700Z-210316T1600Z/
Coastal Del Norte-Northern Humboldt Coast-Southwestern Humboldt-
Southwestern Mendocino Interior-Southeastern Mendocino Interior-
Southern Lake County-
321 AM PDT Mon Mar 15 2021

...FREEZE WATCH IN EFFECT FROM LATE TONIGHT THROUGH TUESDAY
MORNING...

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

* WHERE...Coastal Del Norte, Northern Humboldt Coast, Southwestern
  Humboldt, Southwestern Mendocino Interior, Southeastern
  Mendocino Interior and Southern Lake County.

* WHEN...From late tonight through Tuesday morning.

* IMPACTS...Frost and freeze conditions could kill crops, other
  sensitive vegetation and possibly damage unprotected outdoor
  plumbing.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold. To prevent
freezing and possible bursting of outdoor water pipes they should
be wrapped, drained, or allowed to drip slowly. Those that have
in-ground sprinkler systems should drain them and cover above-
ground pipes to protect them from freezing.

Frost Advisories and Freeze Warnings are issued during the local
growing season as defined by climatology and local agriculture
experts. Once the growing season has ended these statements will
no longer be issued until the spring.

&&

$$
2 follow-up statements
644 
WWUS76 KEKA 151029 CCA
NPWEKA

URGENT - WEATHER MESSAGE...CORRECTED
National Weather Service Eureka CA
329 AM PDT Mon Mar 15 2021

CAZ110-111-114-152200-
/O.NEW.KEKA.HZ.A.0002.210316T0700Z-210316T1600Z/
Northwestern Mendocino Interior-Northeastern Mendocino Interior-
Northern Lake County-
329 AM PDT Mon Mar 15 2021

...HARD FREEZE WATCH IN EFFECT FROM LATE TONIGHT THROUGH TUESDAY
MORNING...

* WHAT...Sub-freezing temperatures as low as 24 possible.

* WHERE...Northwestern Mendocino Interior, Northeastern Mendocino
  Interior and Northern Lake County.

* WHEN...From late tonight through Tuesday morning.

* IMPACTS...Frost and freeze conditions could kill crops, other
  sensitive vegetation and possibly damage unprotected outdoor
  plumbing.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold. To prevent
freezing and possible bursting of outdoor water pipes they should
be wrapped, drained, or allowed to drip slowly. Those that have
in-ground sprinkler systems should drain them and cover above-
ground pipes to protect them from freezing.

Frost Advisories and Freeze Warnings are issued during the local
growing season as defined by climatology and local agriculture
experts. Once the growing season has ended these statements will
no longer be issued until the spring.

&&

$$

CAZ101-103-104-112-113-115-152200-
/O.COR.KEKA.FZ.A.0002.210316T0700Z-210316T1600Z/
Coastal Del Norte-Northern Humboldt Coast-Southwestern Humboldt-
Southwestern Mendocino Interior-Southeastern Mendocino Interior-
Southern Lake County-
329 AM PDT Mon Mar 15 2021

...FREEZE WATCH IN EFFECT FROM LATE TONIGHT THROUGH TUESDAY
MORNING...

* WHAT...Sub-freezing temperatures as low as 29 possible.

* WHERE...Coastal Del Norte, Northern Humboldt Coast, Southwestern
  Humboldt, Southwestern Mendocino Interior, Southeastern
  Mendocino Interior and Southern Lake County.

* WHEN...From late tonight through Tuesday morning.

* IMPACTS...Frost and freeze conditions could kill crops, other
  sensitive vegetation and possibly damage unprotected outdoor
  plumbing.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold. To prevent
freezing and possible bursting of outdoor water pipes they should
be wrapped, drained, or allowed to drip slowly. Those that have
in-ground sprinkler systems should drain them and cover above-
ground pipes to protect them from freezing.

Frost Advisories and Freeze Warnings are issued during the local
growing season as defined by climatology and local agriculture
experts. Once the growing season has ended these statements will
no longer be issued until the spring.

&&

$$
873 
WWUS76 KEKA 152038
NPWEKA

URGENT - WEATHER MESSAGE
National Weather Service Eureka CA
138 PM PDT Mon Mar 15 2021

CAZ110-111-114-161600-
/O.UPG.KEKA.HZ.A.0002.210316T0700Z-210316T1600Z/
/O.NEW.KEKA.HZ.W.0002.210316T0700Z-210316T1600Z/
Northwestern Mendocino Interior-Northeastern Mendocino Interior-
Northern Lake County-
138 PM PDT Mon Mar 15 2021

...HARD FREEZE WARNING IN EFFECT FROM MIDNIGHT TONIGHT TO 9 AM
TUESDAY...

* WHAT...Sub-freezing temperatures as low as 22 expected.

* WHERE...Northwestern Mendocino Interior, Northeastern Mendocino
  Interior and Northern Lake counties.

* WHEN...From midnight tonight to 9 AM Tuesday.

* IMPACTS...Frost and freeze conditions will kill crops, other
  sensitive vegetation and possibly damage unprotected outdoor
  plumbing.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold. To prevent
freezing and possible bursting of outdoor water pipes, they should
be wrapped, drained, or allowed to drip slowly. Those who have 
in-ground sprinkler systems should drain them and cover above- 
ground pipes to protect them from freezing.

$$

CAZ101-103-104-112-113-115-161600-
/O.UPG.KEKA.FZ.A.0002.210316T0700Z-210316T1600Z/
/O.NEW.KEKA.FZ.W.0010.210316T0700Z-210316T1600Z/
Coastal Del Norte-Northern Humboldt Coast-Southwestern Humboldt-
Southwestern Mendocino Interior-Southeastern Mendocino Interior-
Southern Lake County-
138 PM PDT Mon Mar 15 2021

...FREEZE WARNING IN EFFECT FROM MIDNIGHT TONIGHT TO 9 AM TUESDAY...

* WHAT...Sub-freezing temperatures as low as 29 expected.

* WHERE...Coastal Del Norte, Northern Humboldt Coast, Southwestern
  Humboldt, Southwestern Mendocino Interior, Southeastern Mendocino
  Interior and Southern Lake counties.

* WHEN...From midnight tonight to 9 AM Tuesday.

* IMPACTS...Frost and freeze conditions will kill crops, other 
  sensitive vegetation and possibly damage unprotected outdoor 
  plumbing.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold. 

$$

The office that day

Everything else NWS Eureka, CA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 15, 3:29 AM PDTHard Freeze WatchEKALake, Mendocino10 hr
Mar 15, 1:38 PM PDTFreeze WarningEKADel Norte, Humboldt, Mendocino19 hr
Mar 15, 1:38 PM PDTHard Freeze WarningEKALake, Mendocino19 hr

Nearby

Freeze Watches in California, 2021Every freeze watch 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.