Alert archive / Utah / Red Flag Warnings in 2017

Red Flag Warning 2, NWS Salt Lake City, UT

May 25, 2017Washington County, Utah

NWS Salt Lake City, UT issued this red flag warning at May 25, 2017, 9:45 AM MDT for Washington County, Utah. It took effect at May 25, 2017, 3:00 PM MDT. 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
May 25, 2017, 9:45 AM MDT (15:45 UTC)
In effect from
May 25, 2017, 3:00 PM MDT
Expired
May 25, 2017, 8:00 PM MDT
In force
5 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 15:48 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, 3.8 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 2017-05-25Temperature 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 2017-05-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 115 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
3635 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
115 m²/s²
0-3 km storm-relative helicity
93 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

954 
WWUS85 KSLC 251545
RFWSLC

URGENT - FIRE WEATHER MESSAGE
National Weather Service Salt Lake City UT
945 AM MDT Thu May 25 2017

UTZ497-252345-
/O.NEW.KSLC.FW.W.0002.170525T2100Z-170526T0200Z/
Mojave Desert-
945 AM MDT Thu May 25 2017

...RED FLAG WARNING IN EFFECT FROM 3 PM THIS AFTERNOON TO 8 PM
MDT THIS EVENING 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 for wind and low relative humidity...which is in
effect from 3 PM this afternoon to 8 PM MDT this evening.

* AFFECTED AREA...Fire Weather Zone 497 Mojave Desert below 4000
  ft.

* WINDS...West southwest 15-25 mph with gusts 30-35 mph.

* RELATIVE HUMIDITY...4-8%.

* IMPACTS...Gusty winds and low RH will combine to cause critical
  fire weather conditions, especially on southwest and south
  aspects where fuels are most critical. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Red Flag Warning means that critical fire weather conditions 
are either occurring now...or are imminent. 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

The office that day

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

IssuedProductOfficeCountiesLasted
May 24, 6:28 PM MDTSevere Thunderstorm WarningSLCSalt Lake, Tooele32 min
May 24, 6:47 PM MDTSevere Thunderstorm WarningSLCDavis, Salt Lake, Tooele28 min
May 24, 7:13 PM MDTSevere Thunderstorm WarningSLCDavis, Morgan, Salt Lake, Weber32 min
May 24, 8:02 PM MDTSpecial Weather StatementSLCCache28 min

Nearby

Red Flag Warnings in Utah, 2017Every red flag warning in 2017

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.