Alert archive / California / High Wind Watches in 2021

High Wind Watch 6, NWS San Diego, CA

April 4, 2021Riverside County, San Bernardino County, San Diego County, California

NWS San Diego, CA issued this high wind watch at Apr 4, 2021, 1:43 AM PDT for Riverside County, San Bernardino County, San Diego County, California. It took effect at Apr 5, 2021, 2:00 AM PDT. It was in force for .

The area

The counties it named.

The facts

Issued
Apr 4, 2021, 1:43 AM PDT (08:43 UTC)
In effect from
Apr 5, 2021, 2:00 AM PDT
Expired
Apr 4, 2021, 1:28 PM PDT
In force
Issued by
NWS San Diego, CA

Counties Riverside County, CA, San Bernardino County, CA, San Diego County, CA

The radar

The Santa Ana Mts radar (KSOX), 122 km from the middle of the area, began a volume at 08:43 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

San Diego, CA (KNKX), launched 00:00Z, 8.7 hours before the alert went out and 145 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, San Diego, CA at 00:00Z on 2021-04-04Temperature 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, San Diego, CA at 00:00Z on 2021-04-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -20 square meters per square second.193958Sfc1 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
3042 m above ground
0-6 km bulk shear
20 kt
0-1 km storm-relative helicity
-20 m²/s²
0-3 km storm-relative helicity
8 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

897 
WWUS76 KSGX 040843
NPWSGX

URGENT - WEATHER MESSAGE
National Weather Service SAN DIEGO CA
143 AM PDT Sun Apr 4 2021

CAZ055-056-058-065-042100-
/O.NEW.KSGX.HW.A.0006.210405T0900Z-210406T1200Z/
San Bernardino County Mountains-Riverside County Mountains-
San Diego County Mountains-San Gorgonio Pass Near Banning-
Including the cities of Big Bear City, Big Bear Lake, 
Idyllwild-Pine Cove, Julian, Pine Valley, and Desert Hot Springs
143 AM PDT Sun Apr 4 2021

...HIGH WIND WATCH IN EFFECT FROM LATE TONIGHT THROUGH LATE
MONDAY NIGHT...

* WHAT...West winds 30 to 50 mph with gusts 65 to 75 mph 
  possible.

* WHERE...Higher elevations and desert slopes of the San
  Bernardino County Mountains, Riverside County Mountains, San
  Diego County Mountains and San Gorgonio Pass.

* WHEN...From late tonight through late Monday night. Strongest
  winds expected on Monday afternoon and evening. 

* IMPACTS...Damaging winds could blow down trees and power 
  lines. Widespread power outages are possible. Travel could be 
  difficult, especially for high profile vehicles.

* ADDITIONAL DETAILS...Gusty westerly winds will reach the desert
  floor at times where Advisories may be needed. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts and warnings for updates on this
situation. Fasten loose objects or shelter objects in a safe
location prior to the onset of winds.

&&

$$

For more information from the National Weather Service visit
http://weather.gov/sandiego
3 follow-up statements
478 
WWUS76 KSGX 041100
NPWSGX

URGENT - WEATHER MESSAGE
National Weather Service SAN DIEGO CA
400 AM PDT Sun Apr 4 2021

CAZ043-041500-
/O.NEW.KSGX.FG.Y.0003.210404T1100Z-210404T1500Z/
San Diego County Coastal Areas-
Including the cities of Vista, Carlsbad, Encinitas, Chula Vista, 
National City, and San Diego
400 AM PDT Sun Apr 4 2021

...DENSE FOG ADVISORY IN EFFECT UNTIL 8 AM PDT THIS MORNING...

* WHAT...Visibility less than one-quarter mile in dense fog.

* WHERE...San Diego County Coastal Areas.

* WHEN...Until 8 AM PDT this morning.

* IMPACTS...Hazardous driving conditions due to low visibility.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If driving, slow down, use your headlights, and leave plenty of
distance ahead of you.

&&

$$

CAZ055-056-058-065-041900-
/O.CON.KSGX.HW.A.0006.210405T0900Z-210406T1200Z/
San Bernardino County Mountains-Riverside County Mountains-
San Diego County Mountains-San Gorgonio Pass Near Banning-
Including the cities of Big Bear City, Big Bear Lake, 
Idyllwild-Pine Cove, Julian, Pine Valley, and Desert Hot Springs
400 AM PDT Sun Apr 4 2021

...HIGH WIND WATCH REMAINS IN EFFECT FROM LATE TONIGHT THROUGH
LATE MONDAY NIGHT...

* WHAT...West winds 30 to 50 mph with gusts 65 to 75 mph 
  possible.

* WHERE...Higher elevations and desert slopes of the San 
  Bernardino County Mountains, Riverside County Mountains, San 
  Diego County Mountains and San Gorgonio Pass.

* WHEN...From late tonight through late Monday night. Strongest 
  winds expected on Monday afternoon and evening.

* IMPACTS...Damaging winds could blow down trees and power 
  lines. Widespread power outages are possible. Travel could be 
  difficult, especially for high profile vehicles.

* ADDITIONAL DETAILS...Gusty westerly winds will reach the 
  desert floor at times where Advisories may be needed.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts and warnings for updates on this
situation. Fasten loose objects or shelter objects in a safe
location prior to the onset of winds.

&&

$$

For more information from the National Weather Service visit
http://weather.gov/sandiego
140 
WWUS76 KSGX 041533
NPWSGX

URGENT - WEATHER MESSAGE
National Weather Service SAN DIEGO CA
833 AM PDT Sun Apr 4 2021

CAZ043-041800-
/O.NEW.KSGX.FG.Y.0004.210404T1533Z-210404T1800Z/
San Diego County Coastal Areas-
Including the cities of Vista, Carlsbad, Encinitas, Chula Vista, 
National City, and San Diego
833 AM PDT Sun Apr 4 2021

...DENSE FOG ADVISORY IN EFFECT UNTIL 11 AM PDT THIS MORNING...

* WHAT...Visibility one quarter mile or less in dense fog.

* WHERE...San Diego County Coastal Areas.

* WHEN...Until 11 AM PDT this morning.

* IMPACTS...Hazardous driving conditions due to low visibility.

* ADDITIONAL DETAILS...fog should burn off the coast by the middle
  of the day.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If driving, slow down, use your headlights, and leave plenty of
distance ahead of you.

&&

$$

CAZ055-056-058-065-042345-
/O.CON.KSGX.HW.A.0006.210405T0900Z-210406T1200Z/
San Bernardino County Mountains-Riverside County Mountains-
San Diego County Mountains-San Gorgonio Pass Near Banning-
Including the cities of Big Bear City, Big Bear Lake, 
Idyllwild-Pine Cove, Julian, Pine Valley, and Desert Hot Springs
833 AM PDT Sun Apr 4 2021

...HIGH WIND WATCH REMAINS IN EFFECT FROM LATE TONIGHT THROUGH
LATE MONDAY NIGHT...

* WHAT...West winds 30 to 50 mph with gusts to 75 mph possible.

* WHERE...Higher elevations and desert slopes of the San 
  Bernardino County Mountains, Riverside County Mountains, San 
  Diego County Mountains and San Gorgonio Pass.

* WHEN...From late tonight through late Monday night. Strongest 
  winds expected on Monday afternoon and evening.

* IMPACTS...Damaging winds could blow down trees and power 
  lines. Widespread power outages are possible. Travel could be 
  difficult, especially for high profile vehicles.

* ADDITIONAL DETAILS...Gusty westerly winds will reach the 
  desert floor at times where Advisories may be needed.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the latest forecasts and warnings for updates on this
situation. Fasten loose objects or shelter objects in a safe
location prior to the onset of winds.

&&

$$
jmb
For more information from the National Weather Service visit
http://weather.gov/sandiego
911 
WWUS76 KSGX 042028
NPWSGX

URGENT - WEATHER MESSAGE
National Weather Service SAN DIEGO CA
128 PM PDT Sun Apr 4 2021

CAZ055-056-058-065-050500-
/O.UPG.KSGX.HW.A.0006.210405T0900Z-210406T1200Z/
/O.NEW.KSGX.WI.Y.0022.210405T0600Z-210406T1200Z/
San Bernardino County Mountains-Riverside County Mountains-
San Diego County Mountains-San Gorgonio Pass Near Banning-
Including the cities of Crestline, Lake Arrowhead, Big Bear City,
Big Bear Lake, Running Springs, Wrightwood, Idyllwild-Pine Cove, 
Julian, Pine Valley, Banning, and Desert Hot Springs
128 PM PDT Sun Apr 4 2021

...WIND ADVISORY IN EFFECT FROM 11 PM THIS EVENING TO 5 AM PDT
TUESDAY...

* WHAT...West winds 25 to 35 mph with gusts to 55 mph expected. 
  Isolated gusts to 70 mph in the passes and along the desert- 
  facing slopes.

* WHERE...San Bernardino County Mountains, Riverside County 
  Mountains, San Diego County Mountains and San Gorgonio Pass 
  Near Banning.

* WHEN...From 11 PM this evening to 5 AM PDT Tuesday.

* IMPACTS...Gusty winds could blow around unsecured objects and
  make travel difficult for high-profile vehicles.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

CAZ060>062-050500-
/O.NEW.KSGX.WI.Y.0022.210405T0600Z-210406T1200Z/
Apple and Lucerne Valleys-Coachella Valley-
San Diego County Deserts-
Including the cities of Victorville, Hesperia, Apple Valley, 
Indio, Palm Springs, Cathedral City, Palm Desert, 
Palm Desert Country, La Quinta, Coachella, and Borrego Springs
128 PM PDT Sun Apr 4 2021

...WIND ADVISORY IN EFFECT FROM 11 PM THIS EVENING TO 5 AM PDT
TUESDAY...

* WHAT...West winds 20 to 30 mph with gusts to 50 mph expected.

* WHERE...Apple and Lucerne Valleys, Coachella Valley and San 
  Diego County Deserts.

* WHEN...From 11 PM this evening to 5 AM PDT Tuesday.

* IMPACTS...Gusty winds could blow around unsecured objects and
  make travel difficult for high-profile vehicles. Blowing sand
  and dust could severely restrict visibility at times.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

jmb

For more information from the National Weather Service visit
http://weather.gov/sandiego

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 4, 4:00 AM PDTDense Fog AdvisorySGXSan Diego4 hr
Apr 4, 8:33 AM PDTDense Fog AdvisorySGXSan Diego2 hr
Apr 4, 1:28 PM PDTWind AdvisorySGXRiverside, San Bernardino, San Diego40 hr

Nearby

High Wind Watches in California, 2021Every high wind 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.