Alert archive / Utah / Red Flag Warnings in 2012

Red Flag Warning 4, NWS Salt Lake City, UT

May 11, 2012Washington County, Utah

NWS Salt Lake City, UT issued this red flag warning at May 11, 2012, 3:45 PM MDT for Washington County, Utah. It took effect at May 12, 2012, 12:00 AM MDT. 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
May 11, 2012, 3:45 PM MDT (21:45 UTC)
In effect from
May 12, 2012, 12:00 AM MDT
Expired
May 12, 2012, 8:03 AM MDT
In force
8 hr
Issued by
NWS Salt Lake City, UT

County Washington County, UT

The radar

The Cedar City radar (KICX), 66 km from the middle of the area, began a volume at 21:47 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

Las Vegas, NV (KVEF), launched 12:00Z, 9.8 hours before the alert went out and 207 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 12:00Z on 2012-05-11Temperature 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 12:00Z on 2012-05-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 47 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
5127 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
47 m²/s²
0-3 km storm-relative helicity
-31 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.

215 
WWUS85 KSLC 112145
RFWSLC

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
345 PM MDT FRI MAY 11 2012

UTZ497-121200-
/O.NEW.KSLC.FW.W.0004.120512T0600Z-120512T1800Z/
MOJAVE DESERT-
345 PM MDT FRI MAY 11 2012

...RED FLAG WARNING IN EFFECT FROM MIDNIGHT TONIGHT TO NOON MDT
SATURDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONE
497 BELOW 4000 FEET...

THE NATIONAL WEATHER SERVICE IN SALT LAKE CITY HAS ISSUED A RED
FLAG WARNING BELOW 4000 FEET FOR WIND AND LOW RELATIVE HUMIDITY...
WHICH IS IN EFFECT FROM MIDNIGHT TONIGHT TO NOON MDT SATURDAY.

* AFFECTED AREA...FIRE WEATHER ZONE 497 MOJAVE DESERT BELOW 4000
  FEET. SPECIFICALLY FROM THE NEW ST GEORGE AIRPORT NORTH TO THE
  TOWN OF WASHINGTON AND TO THE IRON COUNTY LINE. THIS WARNING
  ALSO INCLUDES WESTERN WASHINGTON COUNTY NEAR THE SOUTHWEST
  SLOPES OF THE BEAVER DAM AND BULL VALLEY MOUNTAINS.

* WINDS...NORTHEAST 10 TO 20 MPH WITH GUSTS UP TO 40 MPH.

* RELATIVE HUMIDITY...ONLY RISING TO 10 TO 15 PERCENT IN THESE
  AREAS OVERNIGHT.

* IMPACTS...THE COMBINATION OF DRY FUELS...LOW RELATIVE HUMIDITY
  VALUES...AND GUSTY NORTHEAST WINDS WILL RESULT IN HAZARDOUS FIRE
  WEATHER CONDITIONS THROUGH SATURDAY MORNING.

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.

&&

$$

ROGOWSKI

FOR MORE INFORMATION FROM NOAA/NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)
2 follow-up statements
029 
WWUS85 KSLC 120925
RFWSLC

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
325 AM MDT SAT MAY 12 2012

UTZ497-121800-
/O.CON.KSLC.FW.W.0004.000000T0000Z-120512T1800Z/
MOJAVE DESERT-
325 AM MDT SAT MAY 12 2012

...RED FLAG WARNING REMAINS IN EFFECT UNTIL NOON MDT TODAY FOR
WIND AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONE 497 BELOW
4000 FEET...

* AFFECTED AREA...FIRE WEATHER ZONE 497 MOJAVE DESERT BELOW 4000
  FEET...SPECIFICALLY ON THE SOUTHERN SLOPES OF THE BEAVER DAM
  MOUNTAINS.

* WINDS...NORTHEAST 10 TO 20 MPH WITH GUSTS OVER 30 MPH.

* RELATIVE HUMIDITY...AS LOW AS 12 PERCENT.

* IMPACTS...THE COMBINATION OF DRY FUELS...LOW RELATIVE HUMIDITY
  VALUES...AND GUSTY NORTHEAST WINDS WILL RESULT IN HAZARDOUS FIRE
  WEATHER CONDITIONS THROUGH THIS MORNING.

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 CRITICALLY DRY FUELS WILL
CREATE EXPLOSIVE FIRE GROWTH POTENTIAL.

&&

$$

FOR MORE INFORMATION FROM NOAA/NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)
157 
WWUS85 KSLC 121403
RFWSLC

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
803 AM MDT SAT MAY 12 2012

UTZ497-121515-
/O.CAN.KSLC.FW.W.0004.000000T0000Z-120512T1800Z/
MOJAVE DESERT-
803 AM MDT SAT MAY 12 2012

...RED FLAG WARNING IS CANCELLED FOR WIND AND LOW RELATIVE
HUMIDITY FOR FIRE WEATHER ZONE 497...

THE NATIONAL WEATHER SERVICE IN SALT LAKE CITY HAS CANCELLED THE
RED FLAG WARNING.

THE GUSTY NORTH WINDS FROM THE OVERNIGHT HOURS HAVE DIMINISHED
EARLY THIS MORNING...AND ARE NO LONGER IN WARNING CRITERIA.
HUMIDITIES WILL REMAIN LOW TODAY.

$$

FOR MORE INFORMATION FROM NOAA/NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)

Nearby

Red Flag Warnings in Utah, 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.