Alert archive / California / Red Flag Warnings in 2006

Red Flag Warning 13, NWS Phoenix, AZ

September 15, 2006Imperial County, Riverside County, San Bernardino County, California; La Paz County, Yuma County, Arizona

NWS Phoenix, AZ issued this red flag warning at Sep 15, 2006, 5:26 AM PDT for Imperial County, Riverside County, San Bernardino County, California; La Paz County, Yuma County, Arizona. It took effect at Sep 15, 2006, 11:00 AM PDT. It was in force for 8 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: Sep 15, 2006, 5:26 AM PDT (12:26 UTC)
In effect from: Sep 15, 2006, 11:00 AM PDT
Expired: Sep 15, 2006, 7:00 PM PDT
In force: 8 hr
Issued by: NWS Phoenix, AZ

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

The radar

The Yuma radar (KYUX), 132 km from the middle of the area, began a volume at 12:24 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, 0.4 hours before the alert went out and 117 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 3238 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: 10 m²/s²
0-3 km storm-relative helicity: 143 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 151226
RFWPSR

RED FLAG WARNING
NATIONAL WEATHER SERVICE PHOENIX AZ
526 AM MST FRI SEP 15 2006

AZZ131-CAZ230>232-160030-
/O.NEW.KPSR.FW.W.0013.060915T1800Z-060916T0200Z/
YUMA/MARTINEZ LAKE AND VICINITY/LOWER COLORADO RIVER VALLEY AZ-
JOSHUA TREE NATIONAL PARK-LOWER COLORADO RIVER VALLEY CA-
IMPERIAL COUNTY AND EASTERN RIVERSIDE COUNTY-
526 AM PDT FRI SEP 15 2006 /526 AM MST FRI SEP 15 2006/

...RED FLAG WARNING IN EFFECT FROM 11 AM MST /11 AM PDT/ THIS
MORNING TO 7 PM MST /7 PM PDT/ THIS EVENING FOR SOUTHEAST
CALIFORNIA AND THE LOWER COLORADO RIVER VALLEY DUE TO EXPECTED LOW
HUMIDITY...STRONG GUSTY WINDS...AND VERY HIGH FIRE DANGER...

THE NATIONAL WEATHER SERVICE IN PHOENIX HAS ISSUED A RED FLAG
WARNING...WHICH IS IN EFFECT FROM 11 AM MST /11 AM PDT/ THIS
MORNING TO 7 PM MST /7 PM PDT/ THIS EVENING. 

AN INTENSE AREA OF LOW PRESSURE MOVING THROUGH THE GREAT BASIN...WILL
GENERATE WIDESPREAD BREEZY CONDITIONS AND GUSTY WINDS BY MIDDAY
ACROSS SOUTHEAST CALIFORNIA AND SOUTH-CENTRAL ARIZONA. STRONG
WESTERLY WINDS...GUSTING UP TO 40 MPH OVER IMPERIAL AND EASTERN
RIVERSIDE COUNTIES IN CALIFORNIA...AND SUSTAINED 20 FOOT WIND SPEEDS
OF 20 MPH BLOWING ACROSS PORTIONS OF THE LOWER COLORADO RIVER
VALLEY...ARE EXPECTED TO PERSIST THROUGHOUT THE AFTERNOON AND EARLY
EVENING HOURS. WINDS WILL GRADUALLY DIMINISH OVER THE AREA AFTER
SUNSET.

A VERY DRY AIR MASS WILL OVER-SPREAD THE REGION IN CONJUNCTION WITH
THE WINDS...WITH MINIMUM RELATIVE HUMIDITY VALUES DROPPING BELOW 15
PERCENT THROUGHOUT THE AFTERNOON...AND INTO THE EVENING HOURS. THE
DRY AIR WILL REMAIN ENTRENCHED OVER THE AREA THROUGH THE WEEKEND...
WITH MINIMUM HUMIDITY VALUES HOVERING IN THE SINGLE DIGITS AT MANY
LOCATIONS SATURDAY. THE LOW HUMIDITIES AND STRONG GUSTY WINDS...
COMBINED WITH A VERY HIGH FIRE DANGER WARRANTS THE ISSUANCE OF THIS
RED FLAG WARNING.


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

$$

MEYERS

1 follow-up statement

000 
WWUS85 KPSR 152126
RFWPSR

RED FLAG WARNING
NATIONAL WEATHER SERVICE PHOENIX AZ
226 PM MST FRI SEP 15 2006

AZZ131-CAZ230>232-160200-
/O.CON.KPSR.FW.W.0013.000000T0000Z-060916T0200Z/
YUMA/MARTINEZ LAKE AND VICINITY/LOWER COLORADO RIVER VALLEY AZ-
JOSHUA TREE NATIONAL PARK-LOWER COLORADO RIVER VALLEY CA-
IMPERIAL COUNTY AND EASTERN RIVERSIDE COUNTY-
226 PM PDT FRI SEP 15 2006 /226 PM MST FRI SEP 15 2006/

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 7 PM MST /7 PM PDT/
THIS EVENING FOR SOUTHEAST CALIFORNIA AND THE LOWER COLORADO RIVER
VALLEY DUE TO STRONG WINDS...LOW HUMIDITY...AND VERY HIGH FIRE
DANGER...

DISCUSSION...MUCH DRIER AIR AND STRONG WINDS HAVE SPREAD ACROSS
SOUTHEAST CALIFORNIA AND THE LOWER COLORADO RIVER VALLEY THIS
AFTERNOON. THIS WAS DUE TO A LARGE UPPER LEVEL LOW MOVING ACROSS THE
WESTERN UNITED STATES. MANY REPORTING STATIONS IN THE WARNED AREA
HAVE OBSERVED RELATIVE HUMIDITY VALUES BELOW 15 PERCENT...AND EVEN
INTO THE SINGLE DIGITS. WINDS HAVE GUSTED TO OR OVER 30 MPH AT MANY
OF THESE SAME LOCATIONS.

THE STRONG WINDS WILL CONTINUE UNTIL 7 PM MDT/PDT...AT WHICH POINT
THEY WILL BEGIN TO WEAKEN. GUSTS TO 25 MPH WILL LIKELY CONTINUE WELL
INTO THE NIGHT ALONG THE EASTERN SLOPES OF MOUNTAINS IN SOUTHEAST
CALIFORNIA SUCH AS THE FISH CREEK...COYOTE...AND CHOCOLATE
MOUNTAINS.

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

$$

INIGUEZ

Nearby

Red Flag Warnings in California, 2006 Red Flag Warnings in Arizona, 2006 Every red flag warning in 2006

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.