Alert archive / California / Red Flag Warnings in 2011

Red Flag Warning 19, NWS Las Vegas, NV

November 1, 2011San Bernardino County, California; Mohave County, Arizona; Clark County, Nevada

NWS Las Vegas, NV issued this red flag warning at Nov 1, 2011, 10:17 PM PDT for San Bernardino County, California; Mohave County, Arizona; Clark County, Nevada. It took effect at Nov 2, 2011, 8:00 AM PDT. It was in force for 9 hr. 3 reports came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Nov 1, 2011, 10:17 PM PDT (05:17 UTC)
In effect from
Nov 2, 2011, 8:00 AM PDT
Expired
Nov 2, 2011, 5:00 PM PDT
In force
9 hr
Issued by
NWS Las Vegas, NV

Counties Mohave County, AZ, San Bernardino County, CA, Clark County, NV

The radar

The Las Vegas radar (KESX), 15 km from the middle of the area, began a volume at 05:17 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.

What was reported inside it

TimeReportWhereRemark
Nov 2, 8:30 AM PDTNON-TSTM WND GST 55Needles Airport, CA
Nov 2, 9:55 AM PDTNON-TSTM WND GST 52Bullhead City Airport, AZ
Nov 2, 10:10 AM PDTNON-TSTM WND DMG2 Nne Needles, CAA SPOTTER REPORTED A FEW MEDIUM SIZED BRANCHES BROKE OFF TREES IN NEEDLES.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Las Vegas, NV (KVEF), launched 00:00Z, 5.3 hours before the alert went out and 101 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, Las Vegas, NV at 00:00Z on 2011-11-02Temperature 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, Las Vegas, NV at 00:00Z on 2011-11-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -55 square meters per square second.1939587897Sfc1 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
4003 m above ground
0-6 km bulk shear
53 kt
0-1 km storm-relative helicity
-55 m²/s²
0-3 km storm-relative helicity
202 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.

104 
WWUS85 KVEF 020517
RFWVEF

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE LAS VEGAS NV
1017 PM PDT TUE NOV 1 2011

AZZ101-CAZ229-NVZ466-021600-
/O.NEW.KVEF.FW.W.0019.111102T1500Z-111103T0000Z/
LAKE MEAD NRA/COLORADO RIVER-AZ SIDE-LOWER COLORADO RIVER VALLEY-
LAKE MEAD NRA/COLORADO RIVER-NV SIDE-
1017 PM PDT TUE NOV 1 2011 /1017 PM MST TUE NOV 1 2011/

...RED FLAG WARNING IN EFFECT FROM 8 AM PDT /8 AM MST/ TO 5 PM
PDT /5 PM MST/ WEDNESDAY FOR STRONG WINDS AND LOW RELATIVE
HUMIDITY FOR FIRE WEATHER ZONES 101...229 AND 466...

THE NATIONAL WEATHER SERVICE IN LAS VEGAS HAS ISSUED A RED FLAG
WARNING FOR STRONG WINDS AND LOW RELATIVE HUMIDITY...WHICH IS IN
EFFECT FROM 8 AM PDT /8 AM MST/ TO 5 PM PDT /5 PM MST/ WEDNESDAY.

* AFFECTED AREA...IN ARIZONA...FIRE WEATHER ZONE 101 LAKE MEAD 
  NRA/COLORADO RIVER-AZ SIDE. IN CALIFORNIA...FIRE WEATHER ZONE 
  229 LOWER COLORADO RIVER VALLEY. IN NEVADA...FIRE WEATHER ZONE 
  466 LAKE MEAD NRA/COLORADO RIVER-NV SIDE.

* TIMING...AFTER SOMEWHAT OF A LULL IN WINDS OVERNIGHT...NORTH
  WINDS WILL INCREASE AGAIN BY MID WEDNESDAY MORNING...PEAKING
  BETWEEN 10 AM AND 2 PM BEFORE DIMINISHING LATE AFTERNOON.

* WIND...NORTH WINDS 20 TO 30 MPH WITH GUSTS TO 45 MPH.

* HUMIDITY...MAINLY BETWEEN 6 AND 12 PERCENT FROM MID MORNING
  THROUGH LATE AFTERNOON. 

* IMPACTS...THE COMBINATION OF STRONG WINDS...LOW HUMIDITY AND 
  DRY FUELS WILL CREATE CONDITIONS FAVORABLE FOR EXTREME FIRE 
  BEHAVIOR. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

HTTP://WEATHER.GOV/LASVEGAS
2 follow-up statements
773 
WWUS85 KVEF 021429
RFWVEF

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE LAS VEGAS NV
729 AM PDT WED NOV 2 2011

AZZ101-CAZ229-NVZ466-030000-
/O.CON.KVEF.FW.W.0019.111102T1500Z-111103T0000Z/
LAKE MEAD NRA/COLORADO RIVER-AZ SIDE-LOWER COLORADO RIVER VALLEY-
LAKE MEAD NRA/COLORADO RIVER-NV SIDE-
729 AM PDT WED NOV 2 2011 /729 AM MST WED NOV 2 2011/

...RED FLAG WARNING IN EFFECT FROM 8 AM PDT/ 8 AM MST UNTIL 5 PM
PDT /5 PM MST/ THIS AFTERNOON FOR STRONG WINDS AND LOW RELATIVE
HUMIDITY FOR FIRE WEATHER ZONES 101...229 AND 466...

A RED FLAG WARNING REMAINS IN EFFECT UNTIL 5 PM PDT /5 PM MST/
THIS AFTERNOON. 

* AFFECTED AREA...IN ARIZONA...FIRE WEATHER ZONE 101 LAKE MEAD 
  NRA/COLORADO RIVER-AZ SIDE. IN CALIFORNIA...FIRE WEATHER ZONE 
  229 LOWER COLORADO RIVER VALLEY. IN NEVADA...FIRE WEATHER ZONE 
  466 LAKE MEAD NRA/COLORADO RIVER-NV SIDE. 

* TIMING...NORTH WINDS WILL INCREASE THIS MORNING...PEAKING
  BETWEEN 10 AM AND 2 PM BEFORE DIMINISHING IN THE LATE AFTERNOON.

* WIND...NORTH WINDS 20 TO 30 MPH WITH GUSTS TO 45 MPH. ISOLATED
  HIGHER GUSTS ARE POSSIBLE IN NORTH WIND PRONE AREAS.

* HUMIDITY...MAINLY BETWEEN 6 AND 12 PERCENT FROM MID MORNING 
  THROUGH LATE AFTERNOON. 

* IMPACTS...THE COMBINATION OF STRONG WINDS...LOW HUMIDITY AND 
  DRY FUELS WILL CREATE CONDITIONS FAVORABLE FOR EXTREME FIRE 
  BEHAVIOR. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

HTTP://WEATHER.GOV/LASVEGAS
356 
WWUS85 KVEF 022340
RFWVEF

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE LAS VEGAS NV
440 PM PDT WED NOV 2 2011

AZZ101-CAZ229-NVZ466-030045-
/O.EXP.KVEF.FW.W.0019.000000T0000Z-111103T0000Z/
LAKE MEAD NRA/COLORADO RIVER-AZ SIDE-LOWER COLORADO RIVER VALLEY-
LAKE MEAD NRA/COLORADO RIVER-NV SIDE-
440 PM PDT WED NOV 2 2011 /440 PM MST WED NOV 2 2011/

...RED FLAG WARNING WILL EXPIRE AT 5 PM PDT /5 PM MST/ THIS
AFTERNOON FOR STRONG WINDS AND LOW RELATIVE HUMIDITY FOR FIRE
WEATHER ZONES 101...229 AND 466...

THE RED FLAG WARNING WILL EXPIRE AT 5 PM PDT /5 PM MST/ THIS
AFTERNOON. 

WINDS WERE DECREASING EARLY THIS EVENING AND GUSTS WERE BELOW 35
MPH AS OF 1630. WINDS WILL CONTINUE TO DECREASE THROUGH THE
EVENING. RELATIVE HUMIDITY WAS STILL PRETTY LOW EARLY THIS EVENING
BUT WILL INCREASE TO ABOVE 20 PERCENT LATER THIS EVENING.

$$

HTTP://WEATHER.GOV/LASVEGAS

Nearby

Red Flag Warnings in California, 2011Red Flag Warnings in Arizona, 2011Red Flag Warnings in Nevada, 2011Every red flag warning in 2011

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.