Alert archive / California / Red Flag Warnings in 2012

Red Flag Warning 8, NWS San Diego, CA

December 10, 20124 counties in California

NWS San Diego, CA issued this red flag warning at Dec 10, 2012, 3:45 AM PST for 4 counties in California. It took effect at Dec 10, 2012, 8:00 AM PST. It was in force for 5 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Dec 10, 2012, 3:45 AM PST (11:45 UTC)
In effect from
Dec 10, 2012, 8:00 AM PST
Expired
Dec 10, 2012, 12:43 PM PST
In force
5 hr
Issued by
NWS San Diego, CA

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

The radar

The Santa Ana Mts radar (KSOX), 88 km from the middle of the area, began a volume at 11:46 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, 11.8 hours before the alert went out and 124 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 2012-12-10Temperature 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 2012-12-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -13 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
2501 m above ground
0-6 km bulk shear
14 kt
0-1 km storm-relative helicity
-13 m²/s²
0-3 km storm-relative helicity
-60 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

505 
WWUS86 KSGX 101145
RFWSGX

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE SAN DIEGO CA
345 AM PST MON DEC 10 2012

...RED FLAG WARNING FOR THE MOUNTAINS AND INLAND VALLEYS TODAY FOR 
STRONG GUSTY WINDS AND LOW RELATIVE HUMIDITIES...

.WEAK TO MODERATE OFFSHORE FLOW WILL CONTINUE INTO THIS AFTERNOON 
WITH GUSTY NORTHEAST WINDS AND LOWER RELATIVE HUMIDITIES 
OCCASIONALLY MEETING RED FLAG CRITERIA FOR AREAS THROUGH AND BELOW 
PASSES AND CANYONS TODAY. SLOW RECOVERY OF HUMIDITIES FOR TONIGHT 
AND TUESDAY WITH LOCALLY GUSTY NORTHEAST WINDS NEAR THE COASTAL 
FOOTHILLS.

CAZ242-248-250-255>258-102200-
/O.CAN.KSGX.FW.W.0007.000000T0000Z-121211T0000Z/
/O.NEW.KSGX.FW.W.0008.121210T1600Z-121211T0000Z/
ORANGE COUNTY COASTAL AREAS-
SAN BERNARDINO AND RIVERSIDE COUNTY VALLEYS-THE INLAND EMPIRE-
SAN DIEGO COUNTY INLAND VALLEYS-SAN BERNARDINO COUNTY MOUNTAINS-
INCLUDING THE MOUNTAIN TOP AND FRONT COUNTRY RANGER DISTRICTS OF
THE SAN BERNARDINO NATIONAL FOREST-RIVERSIDE COUNTY MOUNTAINS-
INCLUDING THE SAN JACINTO RANGER DISTRICT OF THE SAN BERNARDINO
NATIONAL FOREST-SANTA ANA MOUNTAINS-
INCLUDING THE TRABUCO RANGER DISTRICT OF THE CLEVELAND NATIONAL
FOREST-SAN DIEGO COUNTY MOUNTAINS-
INCLUDING THE PALOMAR AND DESCANSO RANGER DISTRICTS OF THE
CLEVELAND NATIONAL FOREST-
345 AM PST MON DEC 10 2012

...RED FLAG WARNING IN EFFECT FROM 8 AM THIS MORNING TO 4 PM PST
THIS AFTERNOON FOR STRONG GUSTY WINDS AND LOW HUMIDITIES...

THE NATIONAL WEATHER SERVICE IN SAN DIEGO HAS ISSUED A RED FLAG
WARNING FOR STRONG GUSTY WINDS AND LOW HUMIDITIES...WHICH IS IN
EFFECT FROM 8 AM THIS MORNING TO 4 PM PST THIS AFTERNOON. 

* WINDS...NORTHEAST 15 TO 25 MPH WITH GUSTS TO 45 MPH.

* RELATIVE HUMIDITY...LOWEST AROUND 10 TO 15 PERCENT.

* LOCATION...THROUGH AND BELOW PASSES AND CANYONS AND NEAR COASTAL FOOTHILLS.

* OUTLOOK...LOCALLY GUSTY NORTHEAST WINDS TO 35 MPH WILL CONTINUE
  NEAR THE COASTAL FOOTHILLS INTO TUESDAY WITH POOR OVERNIGHT
  RECOVERY AND LOWEST DAYTIME HUMIDITIES TUESDAY AROUND 15 PERCENT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A RED FLAG WARNING MEANS THAT CRITICAL FIRE WEATHER CONDITIONS
ARE EITHER OCCURRING NOW...OR WILL SHORTLY. A COMBINATION OF
STRONG WINDS...LOW RELATIVE HUMIDITY...AND WARM TEMPERATURES WILL
CREATE EXPLOSIVE FIRE GROWTH POTENTIAL.

&&

$$

HTTP://WEATHER.GOV/SANDIEG0

17
1 follow-up statement
868 
WWUS86 KSGX 102043
RFWSGX

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE SAN DIEGO CA
1243 PM PST MON DEC 10 2012

CAZ242-248-250-255>258-102145-
/O.CAN.KSGX.FW.W.0008.000000T0000Z-121211T0000Z/
ORANGE COUNTY COASTAL AREAS-
SAN BERNARDINO AND RIVERSIDE COUNTY VALLEYS-THE INLAND EMPIRE-
SAN DIEGO COUNTY INLAND VALLEYS-SAN BERNARDINO COUNTY MOUNTAINS-
INCLUDING THE MOUNTAIN TOP AND FRONT COUNTRY RANGER DISTRICTS OF
THE SAN BERNARDINO NATIONAL FOREST-RIVERSIDE COUNTY MOUNTAINS-
INCLUDING THE SAN JACINTO RANGER DISTRICT OF THE SAN BERNARDINO
NATIONAL FOREST-SANTA ANA MOUNTAINS-
INCLUDING THE TRABUCO RANGER DISTRICT OF THE CLEVELAND NATIONAL
FOREST-SAN DIEGO COUNTY MOUNTAINS-
INCLUDING THE PALOMAR AND DESCANSO RANGER DISTRICTS OF THE
CLEVELAND NATIONAL FOREST-
1243 PM PST MON DEC 10 2012

...RED FLAG WARNING IS CANCELLED FOR STRONG WINDS AND LOW 
HUMIDITIES...

ALTHOUGH CONDITIONS ARE DRY OVER MOST INLAND AREAS...WITH
HUMIDITIES DOWN INTO TEENS TO LOW TWENTIES...OFFSHORE WINDS 
HAVE WEAKENED AND WILL CONTINUE TO WEAKEN THROUGH TUESDAY.
THUS...WITH THE LACK OF SIGNIFICANT WINDS...THE RED FLAG 
WARNING HAS BEEN CANCELLED.

$$

HTTP://WEATHER.GOV/SANDIEG0

HARRISON

The office that day

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

IssuedProductOfficeCountiesLasted
Dec 10, 1:16 PM PSTDense Fog AdvisorySGXSan Diego14 hr

Nearby

Red Flag Warnings in California, 2012Every red flag warning in 2012

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.