Alert archive / California / Wind Advisories in 2010

Wind Advisory 75, NWS Los Angeles, CA

December 20, 2010Los Angeles County, California

NWS Los Angeles, CA issued this wind advisory at Dec 20, 2010, 3:18 PM PST for Los Angeles County, California. It was in force for 6 hr.

The area

The counties it named.

The facts

Issued: Dec 20, 2010, 3:18 PM PST (23:18 UTC)
Expired: Dec 20, 2010, 9:00 PM PST
In force: 6 hr
Issued by: NWS Los Angeles, CA

County Los Angeles County, CA

The radar

The Santa Ana Mts radar (KSOX), 71 km from the middle of the area, began a volume at 23:20 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 12:00Z, 11.3 hours before the alert went out and 184 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 170 J/kg
Mixed-layer CIN: -14 J/kg
Mixed-layer LCL: 447 m above ground
0-6 km bulk shear: 65 kt
0-1 km storm-relative helicity: 126 m²/s²
0-3 km storm-relative helicity: 164 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.4

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this wind advisory went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Los Angeles, CA wrote its last area forecast discussion before this wind advisory went out at Dec 20, 2:30 PM PST, 48 minutes earlier.

Area forecast discussion, Dec 20, 2:30 PM PST, 48 minutes before

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Hazardous weather outlook, Dec 20, 2:55 PM PST, 23 minutes before

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
255 PM PST MON DEC 20 2010

CAZ034>041-044>046-051>054-059-087-088-547-548-211400-
SAN LUIS OBISPO COUNTY CENTRAL COAST-
SANTA BARBARA COUNTY CENTRAL COAST-SANTA YNEZ VALLEY-
SAN LUIS OBISPO COUNTY INTERIOR VALLEYS-CUYAMA VALLEY-
SANTA BARBARA COUNTY SOUTH COAST-VENTURA COUNTY COAST-
LOS ANGELES COUNTY COAST INCLUDING DOWNTOWN LOS ANGELES-
VENTURA COUNTY INTERIOR VALLEYS-VENTURA COUNTY COASTAL VALLEYS-
SANTA MONICA MOUNTAINS RECREATIONAL AREA-
SAN LUIS OBISPO COUNTY MOUNTAINS-
SANTA BARBARA COUNTY MOUNTAINS-VENTURA COUNTY MOUNTAINS-
LOS ANGELES COUNTY MOUNTAINS EXCLUDING THE SANTA MONICA RANGE-
ANTELOPE VALLEY-CATALINA ISLAND-SANTA CLARITA VALLEY-
LOS ANGELES COUNTY SAN FERNANDO VALLEY-
LOS ANGELES COUNTY SAN GABRIEL VALLEY-
255 PM PST MON DEC 20 2010

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHWESTERN CALIFORNIA.

.DAY ONE... THROUGH TONIGHT

PERIODS OF RAIN WILL CONTINUE ACROSS THE AREA THROUGH TONIGHT. THE
HEAVY RAINFALL WILL PRODUCE LOCAL NUISANCE FLOODING OF LOW LYING
AREAS SUCH AS UNDERPASSES. FOR THE RECENT BURN AREAS...THERE IS THE
POTENTIAL FOR HIGH RAINFALL RATES WHICH COULD PRODUCE MUD AND DEBRIS
FLOWS. LOWERED SNOW LEVELS HAVE BROUGHT LIGHT TO MODERATE SNOWFALL
TO THE MOUNTAINS ABOVE 5000 FEET ELEVATION OF VENTURA AND SANTA
BARBARA COUNTIES...AND WILL CONTINUE THROUGH AT LEAST TONIGHT WHILE
SPREADING INTO THE LOS ANGELES COUNTY MOUNTAINS. BEACH GOERS WILL
FACE AN ENHANCED RISK OF RIP CURRENTS.

* FLASH FLOOD WATCH..........SEE WGUS66 KLOX - FFALOX FOR DETAILS *

* WINTER WEATHER ADVISORY....SEE WWUS46 KLOX - WSWLOX FOR DETAILS *

* HIGH RIP CURRENT RISK......SEE FZUS56 KLOX - SRFLOX FOR DETAILS *

.DAYS TWO THROUGH SEVEN... TUESDAY THROUGH SUNDAY

THE WET PATTERN IS EXPECTED TO CONTINUE ACROSS THE AREA THROUGH
WEDNESDAY. THE ADDITIONAL RAINFALL WILL CONTINUE TO BRING DRIVING
AND FLOODING ISSUES TO THE AREA. SNOW ACCUMULATIONS WILL INCREASE
ABOVE 6000 FEET ELEVATION TUESDAY AND WEDNESDAY WITH SIGNIFICANT
SNOWFALL EXPECTED TUESDAY NIGHT AND WEDNESDAY. STRONG SOUTHERLY
WINDS WILL LIKELY IMPACT THE MOUNTAIN TUESDAY NIGHT...WITH DAMAGING
GUSTS POSSIBLE. THERE WILL ALSO BE THE THREAT OF THUNDERSTORMS
EVERYWHERE TUESDAY NIGHT AND WEDNESDAY. DRY CONDITIONS ARE EXPECTED
ON THURSDAY AND FRIDAY. BY LATE CHRISTMAS DAY...ANOTHER BUT MUCH
WEAKER STORM SYSTEM IS EXPECTED TO APPROACH SAN LUIS OBISPO
COUNTY...BRINGING A POSSIBILITY OF RAIN TO ALL AREAS BY SUNDAY.

* HIGH WIND WATCH............SEE WWUS76 KLOX - NPWLOX FOR DETAILS *

* FLASH FLOOD WATCH..........SEE WGUS66 KLOX - FFALOX FOR DETAILS *

* WINTER STORM WATCH.........SEE WWUS46 KLOX - WSWLOX FOR DETAILS *

* WINTER WEATHER ADVISORY....SEE WWUS46 KLOX - WSWLOX FOR DETAILS *

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

SIRARD

The office that day

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

Issued	Product	Office	Counties	Lasted
Dec 20, 2:55 AM PST	Small Craft Advisory for Hazardous Seas	LOX		25 hr
Dec 20, 10:05 AM PST	Winter Weather Advisory	LOX		32 hr
Dec 20, 1:08 PM PST	Areal Flood Advisory	LOX	Los Angeles	3 hr
Dec 20, 3:12 PM PST	Winter Storm Watch	LOX		12 hr
Dec 20, 3:18 PM PST	High Wind Watch	LOX		13 hr
Dec 20, 3:53 PM PST	Areal Flood Advisory	LOX	Los Angeles	3 hr

Nearby

Wind Advisories in California, 2010 Every wind advisory in 2010

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.