Alert archive / Utah / Red Flag Warnings in 2013

Red Flag Warning 21, NWS Salt Lake City, UT

August 17, 20135 counties in Utah

NWS Salt Lake City, UT issued this red flag warning at Aug 17, 2013, 2:51 AM MDT for 5 counties in Utah. It took effect at Aug 17, 2013, 12:00 PM MDT. It was in force for 9 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
Aug 17, 2013, 2:51 AM MDT (08:51 UTC)
In effect from
Aug 17, 2013, 12:00 PM MDT
Expired
Aug 17, 2013, 9:00 PM MDT
In force
9 hr
Issued by
NWS Salt Lake City, UT

Counties Box Elder County, UT, Davis County, UT, Salt Lake County, UT, Tooele County, UT, Utah County, UT

The radar

The Salt Lake City radar (KMTX), 57 km from the middle of the area, began a volume at 08:56 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

Salt Lake City I, UT (KSLC), launched 00:00Z, 8.9 hours before the alert went out and 41 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, Salt Lake City I, UT at 00:00Z on 2013-08-17Temperature 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, Salt Lake City I, UT at 00:00Z on 2013-08-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 12 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
4242 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
12 m²/s²
0-3 km storm-relative helicity
59 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.

744 
WWUS85 KSLC 170851
RFWSLC

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
251 AM MDT SAT AUG 17 2013

UTZ478-172200-
/O.UPG.KSLC.FW.A.0010.130817T1800Z-130818T0300Z/
/O.NEW.KSLC.FW.W.0021.130817T1800Z-130818T0300Z/
SALT LAKE DESERT-
251 AM MDT SAT AUG 17 2013

...RED FLAG WARNING IN EFFECT FROM NOON TODAY TO 9 PM MDT THIS
EVENING FOR WIND AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONE
478...

THE NATIONAL WEATHER SERVICE IN SALT LAKE CITY HAS ISSUED A RED
FLAG WARNING FOR WIND AND LOW RELATIVE HUMIDITY...WHICH IS IN
EFFECT FROM NOON TODAY TO 9 PM MDT THIS EVENING. THE FIRE WEATHER
WATCH IS NO LONGER IN EFFECT.

* AFFECTED AREA...FIRE WEATHER ZONE 478 SALT LAKE DESERT.

* OUTFLOW WINDS...STRONG OUTFLOW WINDS WITH GUSTS OVER 40 MPH 
  WILL BE POSSIBLE WITH SHOWERS AND THUNDERSTORMS. 

* RELATIVE HUMIDITY...HUMIDITY VALUES IN THE 5 TO 15 PERCENT 
  RANGE...WITH THE LOWEST VALUES DURING THE AFTERNOON HOURS. 

* IMPACTS...ANY EXISTING FIRES ARE EXPECTED TO EXHIBIT EXTREME
  FIRE BEHAVIOR. LIGHTNING FROM ANY THUNDERSTORMS DEVELOPING ON
  SATURDAY WILL LIKELY CONTRIBUTE TO NEW STARTS.

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 CAN
CONTRIBUTE TO EXTREME FIRE BEHAVIOR.

&&

$$

FOR MORE INFORMATION FROM NOAA/NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)
2 follow-up statements
619 
WWUS85 KSLC 171457
RFWSLC

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
857 AM MDT SAT AUG 17 2013

UTZ478-180300-
/O.CON.KSLC.FW.W.0021.130817T1800Z-130818T0300Z/
SALT LAKE DESERT-
857 AM MDT SAT AUG 17 2013

...RED FLAG WARNING REMAINS IN EFFECT FROM NOON TODAY TO 9 PM MDT
THIS EVENING FOR DRY THUNDERSTORMS AND GUSTY OUTFLOW WINDS FOR
FIRE WEATHER ZONE 478...

* AFFECTED AREA...FIRE WEATHER ZONE 478 SALT LAKE DESERT.

* THUNDERSTORMS...WIDELY SCATTERED DRY THUNDERSTORMS ARE EXPECTED
  TO DEVELOP THIS AFTERNOON AND EVENING.

* OUTFLOW WINDS...STRONG OUTFLOW WINDS WITH GUSTS OVER 40 MPH WILL
  BE POSSIBLE.

* RELATIVE HUMIDITY...HUMIDITY VALUES IN THE 5 TO 15 PERCENT 
  RANGE...WITH THE LOWEST VALUES DURING THE AFTERNOON HOURS. 

* IMPACTS...ANY EXISTING FIRES ARE EXPECTED TO EXHIBIT EXTREME 
  FIRE BEHAVIOR. LIGHTNING FROM ANY THUNDERSTORMS DEVELOPING ON 
  SATURDAY WILL LIKELY CONTRIBUTE TO NEW STARTS. 

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 CAN
CONTRIBUTE TO EXTREME FIRE BEHAVIOR.

&&

$$

FOR MORE INFORMATION FROM NOAA/NATIONAL WEATHER SERVICE VISIT...
HTTP://WEATHER.GOV/SALTLAKECITY (ALL LOWER CASE)
529 
WWUS85 KSLC 172124
RFWSLC

URGENT - FIRE WEATHER MESSAGE
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
324 PM MDT SAT AUG 17 2013

UTZ478-180300-
/O.CON.KSLC.FW.W.0021.000000T0000Z-130818T0300Z/
SALT LAKE DESERT-
324 PM MDT SAT AUG 17 2013

...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM MDT THIS EVENING
FOR DRY THUNDERSTORMS AND GUSTY OUTFLOW WINDS FOR FIRE WEATHER
ZONE 478...

* AFFECTED AREA...FIRE WEATHER ZONE 478 SALT LAKE DESERT.

* THUNDERSTORMS...WIDELY SCATTERED DRY THUNDERSTORMS ARE EXPECTED
  THROUGH THIS EVENING...MAINLY OVER WESTERN PORTIONS OF THE ZONE.
  WETTING RAINS CAN BE EXPECTED WITH STORMS OVER THE EASTERN
  PORTION OF THE ZONE. 

* OUTFLOW WINDS...STRONG OUTFLOW WINDS WITH GUSTS OVER 40 MPH 
  WILL BE POSSIBLE. 

* RELATIVE HUMIDITY...HUMIDITY VALUES IN THE 5 TO 15 PERCENT 
  RANGE...WITH THE LOWEST VALUES DURING THE AFTERNOON HOURS. 

* IMPACTS...ANY EXISTING FIRES ARE EXPECTED TO EXHIBIT EXTREME 
  FIRE BEHAVIOR. LIGHTNING FROM ANY THUNDERSTORMS DEVELOPING ON 
  SATURDAY WILL LIKELY CONTRIBUTE TO NEW STARTS. 

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 CAN
CONTRIBUTE TO EXTREME FIRE BEHAVIOR.

&&

$$

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

The office that day

Everything else NWS Salt Lake City, UT issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 17, 9:36 AM MDTFlash Flood WarningSLCGarfield, Kane3 hr
Aug 17, 12:20 PM MDTFlash Flood WarningSLCCarbon, Emery3 hr
Aug 17, 1:19 PM MDTFlash Flood WarningSLCJuab, Millard3 hr
Aug 17, 3:14 PM MDTAreal Flood AdvisorySLCUtah2 hr

Nearby

Red Flag Warnings in Utah, 2013Every red flag warning in 2013

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.