Alert archive / California / Wind Advisories in 2021

Wind Advisory 11, NWS Eureka, CA

May 20, 2021Mendocino County, California

NWS Eureka, CA issued this wind advisory at May 20, 2021, 3:35 AM PDT for Mendocino County, California. It took effect at May 20, 2021, 12:00 PM PDT. It was in force for 2 hr.

The area

The counties it named.

The facts

Issued
May 20, 2021, 3:35 AM PDT (10:35 UTC)
In effect from
May 20, 2021, 12:00 PM PDT
Expired
May 20, 2021, 2:09 PM PDT
In force
2 hr
Issued by
NWS Eureka, CA

County Mendocino County, CA

The radar

The Eureka (Bunker Hill) radar (KBHX), 139 km from the middle of the area, began a volume at 10:34 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

Oakland, CA (KOAK), launched 00:00Z, 10.6 hours before the alert went out and 218 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, Oakland, CA at 00:00Z on 2021-05-20Temperature 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, Oakland, CA at 00:00Z on 2021-05-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -29 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
1618 m above ground
0-6 km bulk shear
35 kt
0-1 km storm-relative helicity
-29 m²/s²
0-3 km storm-relative helicity
-7 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

165 
WWUS76 KEKA 201035
NPWEKA

URGENT - WEATHER MESSAGE
National Weather Service Eureka CA
335 AM PDT Thu May 20 2021

CAZ113-115-201600-
/O.CAN.KEKA.WI.Y.0010.000000T0000Z-210521T0000Z/
/O.NEW.KEKA.WI.Y.0011.210520T1900Z-210521T0000Z/
/O.CON.KEKA.FR.Y.0036.000000T0000Z-210520T1600Z/
Southeastern Mendocino Interior-Southern Lake-
335 AM PDT Thu May 20 2021

...FROST ADVISORY REMAINS IN EFFECT UNTIL 9 AM PDT THIS MORNING...
...WIND ADVISORY IN EFFECT FROM NOON TODAY TO 5 PM PDT THIS
AFTERNOON...

* WHAT...For the Frost Advisory, temperatures as low as 35 will 
  result in frost formation. For the Wind Advisory, northwest 
  winds 15 to 25 mph with gusts up to 40 to 45 mph expected.

* WHERE...Portions of the Southeastern Mendocino Interior and 
  Southern Lake Counties.

* WHEN...For the Frost Advisory, until 9 AM PDT this morning. 
  For the Wind Advisory, from noon today to 5 PM PDT this 
  afternoon.

* IMPACTS...Gusty winds could blow around unsecured objects. 
  Tree limbs could be blown down and a few power outages may 
  result. Frost could kill sensitive outdoor vegetation if left 
  uncovered.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Use extra caution when driving, especially if operating a high
profile vehicle. Secure outdoor objects.

Take steps now to protect tender plants from the cold.

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.

&&

$$

CAZ110-114-201600-
/O.CAN.KEKA.WI.Y.0010.000000T0000Z-210521T0000Z/
/O.CON.KEKA.FR.Y.0036.000000T0000Z-210520T1600Z/
Northwestern Mendocino Interior-Northern Lake-
335 AM PDT Thu May 20 2021

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

* WHAT...Temperatures in the low to mid 30s will result in frost 
  formation.

* WHERE...Northwestern Mendocino Interior and Northern Lake 
  Counties.

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

* IMPACTS...Frost could kill sensitive outdoor vegetation if 
  left uncovered.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold.

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.

&&

$$

CAZ112-201600-
/O.CAN.KEKA.WI.Y.0010.000000T0000Z-210521T0000Z/
/O.NEW.KEKA.WI.Y.0011.210520T1900Z-210521T0000Z/
Southwestern Mendocino Interior-
335 AM PDT Thu May 20 2021

...WIND ADVISORY IN EFFECT FROM NOON TODAY TO 5 PM PDT THIS
AFTERNOON...

* WHAT...Northwest winds 15 to 25 mph with gusts up to 40 to 45  
  mph expected.

* WHERE...Southwestern Mendocino Interior County.

* WHEN...From noon today to 5 PM PDT this afternoon.

* IMPACTS...Gusty winds could blow around unsecured objects. 
  Tree limbs could be blown down and a few power outages may 
  result.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

Use extra caution when driving, especially if operating a high
profile vehicle. Secure outdoor objects.

&&

$$

CAZ102-104>108-111-201600-
/O.CON.KEKA.FR.Y.0036.000000T0000Z-210520T1600Z/
Del Norte Interior-Southwestern Humboldt-
Northern Humboldt Interior-Southern Humboldt Interior-
Northern Trinity-Southern Trinity-Northeastern Mendocino Interior-
335 AM PDT Thu May 20 2021

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

* WHAT...Temperatures in the low to mid 30s will result in frost 
  formation.

* WHERE...Sheltered portions of Southern Trinity, Del Norte 
  Interior, Northeastern Mendocino Interior, Northern Humboldt 
  Interior, Southwestern Humboldt, Northern Trinity and Southern 
  Humboldt Interior Counties.

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

* IMPACTS...Frost could kill sensitive outdoor vegetation if 
  left uncovered.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold.

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.

&&

$$
1 follow-up statement
352 
WWUS76 KEKA 202109
NPWEKA

URGENT - WEATHER MESSAGE
National Weather Service Eureka CA
209 PM PDT Thu May 20 2021

CAZ112-113-115-202215-
/O.CAN.KEKA.WI.Y.0011.000000T0000Z-210521T0000Z/
Southwestern Mendocino Interior-Southeastern Mendocino Interior-
Southern Lake-
209 PM PDT Thu May 20 2021

...WIND ADVISORY IS CANCELLED...

$$

CAZ102-105>108-110-111-210515-
/O.NEW.KEKA.FR.Y.0037.210521T0800Z-210521T1600Z/
Del Norte Interior-Northern Humboldt Interior-
Southern Humboldt Interior-Northern Trinity-Southern Trinity-
Northwestern Mendocino Interior-Northeastern Mendocino Interior-
209 PM PDT Thu May 20 2021

...FROST ADVISORY IN EFFECT FROM 1 AM TO 9 AM PDT FRIDAY...

* WHAT...Temperatures as low as 29 will result in frost 
  formation.

* WHERE...Del Norte Interior, Northern Humboldt Interior, 
  Southern Humboldt Interior, Northern Trinity, Southern 
  Trinity, Northwestern Mendocino Interior and Northeastern 
  Mendocino Interior Counties.

* WHEN...From 1 AM to 9 AM PDT Friday.

* IMPACTS...Frost could kill sensitive outdoor vegetation if 
  left uncovered.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold.

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.

&&

$$

The office that day

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

IssuedProductOfficeCountiesLasted
May 19, 8:08 PM PDTGale WarningEKA24 hr
May 19, 8:08 PM PDTSmall Craft AdvisoryEKA15 hr
May 20, 2:09 PM PDTFrost AdvisoryEKADel Norte, Humboldt, Lake, Mendocino, Trinity19 hr

Nearby

Wind Advisories in California, 2021Every wind 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.