Alert archive / California / Red Flag Warnings in 2007

Red Flag Warning 21, NWS Phoenix, AZ

December 31, 2007Imperial County, Riverside County, California; La Paz County, Yuma County, Arizona

NWS Phoenix, AZ issued this red flag warning at Dec 31, 2007, 1:31 PM PST for Imperial County, Riverside County, California; La Paz County, Yuma County, Arizona. 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 31, 2007, 1:31 PM PST (21:31 UTC)
Expired
Dec 31, 2007, 7:00 PM PST
In force
5 hr
Issued by
NWS Phoenix, AZ

Counties La Paz County, AZ, Yuma County, AZ, Imperial County, CA, Riverside County, CA

The radar

The Yuma radar (KYUX), 93 km from the middle of the area, began a volume at 21:31 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

Yuma Intl Airpor, AZ (KYUM), launched 12:00Z, 9.5 hours before the alert went out and 77 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, Yuma Intl Airpor, AZ at 12:00Z on 2007-12-31Temperature 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, Yuma Intl Airpor, AZ at 12:00Z on 2007-12-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -7 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
2107 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
-7 m²/s²
0-3 km storm-relative helicity
6 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.

000 
WWUS85 KPSR 312131
RFWPSR

RED FLAG WARNING
NATIONAL WEATHER SERVICE PHOENIX AZ
231 PM MST MON DEC 31 2007

AZZ131-CAZ231-232-010300-
/O.NEW.KPSR.FW.W.0021.071231T2131Z-080101T0300Z/
ARIZONA FIRE WEATHER ZONE 131                                    
YUMA/MARTINEZ LAKE AND VICINITY/LOWER COLORADO RIVER VALLEY AZ-
CALIFORNIA FIRE WEATHER ZONE 231                                 
LOWER COLORADO RIVER VALLEY CA-
CALIFORNIA FIRE WEATHER ZONE 232                                 
IMPERIAL COUNTY AND EASTERN RIVERSIDE COUNTY-
231 PM MST MON DEC 31 2007 /131 PM PST MON DEC 31 2007/

...RED FLAG WARNING IN EFFECT UNTIL 8 PM MST /7 PM PST/ THIS
EVENING FOR LOWER COLORADO RIVER VALLEY...IMPERIAL COUNTY AND
EASTERN RIVERSIDE COUNTY FOR GUSTY WINDS AND LOW HUMIDITY...

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A RED FLAG
WARNING...WHICH IS IN EFFECT UNTIL 8 PM MST /7 PM PST/ THIS
EVENING. 

WINDS SHIFTED RAPIDLY AND THE HUMIDITY DIPPED INTO THE TEENS ACROSS
PORTIONS OF EASTERN RIVERSIDE COUNTY EARLY THIS AFTERNOON. IN FACT
THE WINDS GUSTED TO 36 MPH AND THE RH DROPPED TO 13 PERCENT AT
BLYTHE AT 1 PM PST. 

NORTH WINDS WILL CONTINUE TO GUST TO OVER 35 MPH...AND THE HUMIDITY
WILL REMAIN AT OR BELOW 15 PERCENT ALONG THE LOWER COLORADO RIVER
VALLEY...EASTERN RIVERSIDE AND IMPERIAL COUNTY THROUGHOUT THIS
AFTERNOON AND EARLY EVENING. CRITICAL FIRE WEATHER CONDITIONS ARE
EXPECTED TO END BY 8 PM MST OR 7 PM PST. 

PLEASE ADVISE THE APPROPRIATE OFFICIALS AND FIRE CREWS IN THE FIELD
OF THIS RED FLAG WARNING.

$$
SIPPLE

Nearby

Red Flag Warnings in California, 2007Red Flag Warnings in Arizona, 2007Every red flag warning in 2007

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.