Alert archive / Utah / Red Flag Warnings in 2021
Red Flag Warning 8, NWS Salt Lake City, UT
NWS Salt Lake City, UT issued this red flag warning at May 13, 2021, 3:35 AM MDT for 7 counties in Utah. It took effect at May 14, 2021, 11:00 AM MDT. It was in force for 58 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 13, 2021, 3:35 AM MDT (09:35 UTC)
- In effect from
- May 14, 2021, 11:00 AM MDT
- Expired
- May 16, 2021, 9:00 PM MDT
- In force
- 58 hr
- Issued by
- NWS Salt Lake City, UT
Counties Beaver County, UT, Garfield County, UT, Iron County, UT, Kane County, UT, San Juan County, UT, Washington County, UT, Wayne County, UT
The radar
The Cedar City radar (KICX), 78 km from the middle of the area, began a volume at 09:39 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
Flgstf/Belemont, AZ (KFGZ), launched 00:00Z, 9.6 hours before the alert went out and 286 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.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 4501 m above ground
- 0-6 km bulk shear
- 16 kt
- 0-1 km storm-relative helicity
- 0 m²/s²
- 0-3 km storm-relative helicity
- -33 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
468 WWUS85 KSLC 130935 RFWSLC URGENT - FIRE WEATHER MESSAGE National Weather Service Salt Lake City UT 335 AM MDT Thu May 13 2021 UTZ498-131745- /O.UPG.KSLC.FW.A.0005.210515T1500Z-210516T0300Z/ /O.NEW.KSLC.FW.W.0008.210514T1700Z-210516T0300Z/ Grand Staircase- 335 AM MDT Thu May 13 2021 ...RED FLAG WARNING IN EFFECT FROM 11 AM FRIDAY TO 9 PM MDT SATURDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONE 498... 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 11 AM Friday to 9 PM MDT Saturday. * AFFECTED AREA...Fire Weather Zone 498 Grand Staircase. * WINDS...Southwest 10 to 20 mph with gusts up to 35 mph. * RELATIVE HUMIDITY...As low as 5 percent. * IMPACTS...Any fires that develop could spread rapidly. Outdoor burning is not recommended. 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. && $$ UTZ497-131745- /O.UPG.KSLC.FW.A.0005.210515T1500Z-210516T0300Z/ /O.NEW.KSLC.FW.W.0008.210515T1700Z-210516T0300Z/ Mojave Desert- 335 AM MDT Thu May 13 2021 ...RED FLAG WARNING IN EFFECT FROM 11 AM TO 9 PM MDT SATURDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONE 497... The National Weather Service in Salt Lake City has issued a Red Flag Warning for wind and low relative humidity, which is in effect from 11 AM to 9 PM MDT Saturday. * AFFECTED AREA...Fire Weather Zone 497 Mojave Desert. * WINDS...South 15 to 25 mph with gusts up to 40 mph. * RELATIVE HUMIDITY...As low as 9 percent. * IMPACTS...Any fires that develop could spread rapidly. Outdoor burning is not recommended. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now...or are imminent. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ For more information from NOAA/National Weather Service visit... http://weather.gov/saltlakecity
10 follow-up statements
230 WWUS85 KSLC 131619 RFWSLC URGENT - FIRE WEATHER MESSAGE National Weather Service Salt Lake City UT 1019 AM MDT Thu May 13 2021 UTZ498-132300- /O.CON.KSLC.FW.W.0008.210514T1700Z-210516T0300Z/ Grand Staircase- 1019 AM MDT Thu May 13 2021 ...RED FLAG WARNING REMAINS IN EFFECT FROM 11 AM FRIDAY TO 9 PM MDT SATURDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONE 498... * AFFECTED AREA...Fire Weather Zone 498 Grand Staircase. * WINDS...Southwest 10 to 20 mph with gusts up to 35 mph. * RELATIVE HUMIDITY...As low as 5 percent. * IMPACTS...Any fires that develop could spread rapidly. Outdoor burning is not recommended. 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. && $$ UTZ497-132300- /O.CON.KSLC.FW.W.0008.210515T1700Z-210516T0300Z/ Mojave Desert- 1019 AM MDT Thu May 13 2021 ...RED FLAG WARNING REMAINS IN EFFECT FROM 11 AM TO 9 PM MDT SATURDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONE 497... * AFFECTED AREA...Fire Weather Zone 497 Mojave Desert. * WINDS...Southwest 15 to 25 mph with gusts up to 40 mph. * RELATIVE HUMIDITY...As low as 9 percent. * IMPACTS...Any fires that develop could spread rapidly. Outdoor burning is not recommended. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now...or are imminent. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ For more information from NOAA/National Weather Service visit... http://weather.gov/saltlakecity
691 WWUS85 KSLC 132137 RFWSLC URGENT - FIRE WEATHER MESSAGE National Weather Service Salt Lake City UT 337 PM MDT Thu May 13 2021 UTZ498-141200- /O.CON.KSLC.FW.W.0008.210514T1700Z-210516T0300Z/ Grand Staircase- 337 PM MDT Thu May 13 2021 ...RED FLAG WARNING REMAINS IN EFFECT FROM 11 AM FRIDAY TO 9 PM MDT SATURDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONE 498... * AFFECTED AREA...Fire Weather Zone 498 Grand Staircase. * WINDS...Southwest 10 to 20 mph with gusts up to 35 mph. * RELATIVE HUMIDITY...As low as 5 percent. * IMPACTS...Any fires that develop could spread rapidly. Outdoor burning is not recommended. 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. && $$ UTZ497-141200- /O.CON.KSLC.FW.W.0008.210515T1700Z-210516T0300Z/ Mojave Desert- 337 PM MDT Thu May 13 2021 ...RED FLAG WARNING REMAINS IN EFFECT FROM 11 AM TO 9 PM MDT SATURDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONE 497... * AFFECTED AREA...Fire Weather Zone 497 Mojave Desert. * WINDS...Southwest 15 to 25 mph with gusts up to 40 mph. * RELATIVE HUMIDITY...As low as 9 percent. * IMPACTS...Any fires that develop could spread rapidly. Outdoor burning is not recommended. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now...or are imminent. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ For more information from NOAA/National Weather Service visit... http://weather.gov/saltlakecity
466 WWUS85 KSLC 140911 RFWSLC URGENT - FIRE WEATHER MESSAGE National Weather Service Salt Lake City UT 311 AM MDT Fri May 14 2021 UTZ498-142300- /O.CON.KSLC.FW.W.0008.210514T1700Z-210516T0300Z/ Grand Staircase- 311 AM MDT Fri May 14 2021 ...RED FLAG WARNING REMAINS IN EFFECT FROM 11 AM THIS MORNING TO 9 PM MDT SATURDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONE 498... * AFFECTED AREA...Fire Weather Zone 498 Grand Staircase. * WINDS...Southwest 10 to 20 mph with gusts up to 35 mph. * RELATIVE HUMIDITY...As low as 5 percent. * IMPACTS...Any fires that develop could spread rapidly. Outdoor burning is not recommended. 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. && $$ UTZ497-142300- /O.CON.KSLC.FW.W.0008.210515T1700Z-210516T0300Z/ Mojave Desert- 311 AM MDT Fri May 14 2021 ...RED FLAG WARNING REMAINS IN EFFECT FROM 11 AM TO 9 PM MDT SATURDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONE 497... * AFFECTED AREA...Fire Weather Zone 497 Mojave Desert. * WINDS...Southwest 15 to 25 mph with gusts up to 40 mph. * RELATIVE HUMIDITY...As low as 9 percent. * IMPACTS...Any fires that develop could spread rapidly. Outdoor burning is not recommended. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now...or are imminent. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ For more information from NOAA/National Weather Service visit... http://weather.gov/saltlakecity
098 WWUS85 KSLC 141841 RFWSLC URGENT - FIRE WEATHER MESSAGE National Weather Service Salt Lake City UT 1241 PM MDT Fri May 14 2021 UTZ498-142300- /O.CON.KSLC.FW.W.0008.000000T0000Z-210516T0300Z/ Grand Staircase- 1241 PM MDT Fri May 14 2021 ...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM MDT SATURDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONE 498... * AFFECTED AREA...Fire Weather Zone 498 Grand Staircase. * WINDS...Southwest 10 to 20 mph with gusts up to 35 mph. * RELATIVE HUMIDITY...As low as 5 percent. * IMPACTS...Any fires that develop could spread rapidly. Outdoor burning is not recommended. 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. && $$ UTZ497-142300- /O.CON.KSLC.FW.W.0008.210515T1700Z-210516T0300Z/ Mojave Desert- 1241 PM MDT Fri May 14 2021 ...RED FLAG WARNING REMAINS IN EFFECT FROM 11 AM TO 9 PM MDT SATURDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONE 497... * AFFECTED AREA...Fire Weather Zone 497 Mojave Desert. * WINDS...Southwest 15 to 25 mph with gusts up to 40 mph. * RELATIVE HUMIDITY...As low as 9 percent. * IMPACTS...Any fires that develop could spread rapidly. Outdoor burning is not recommended. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now...or are imminent. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ For more information from NOAA/National Weather Service visit... http://weather.gov/saltlakecity
456 WWUS85 KSLC 142017 RFWSLC URGENT - FIRE WEATHER MESSAGE National Weather Service Salt Lake City UT 217 PM MDT Fri May 14 2021 UTZ495-150600- /O.EXB.KSLC.FW.W.0008.210515T1700Z-210517T0300Z/ Color Country West Desert- 217 PM MDT Fri May 14 2021 ...RED FLAG WARNING IN EFFECT FROM 11 AM SATURDAY TO 9 PM MDT SUNDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONE 495... 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 11 AM Saturday to 9 PM MDT Sunday. * AFFECTED AREA...Fire Weather Zone 495 Color Country West Desert. * WINDS...South to southwest 10 to 20 mph with gusts up to 35 mph. * RELATIVE HUMIDITY...As low as 10 percent. Poor overnight recoveries are expected. * IMPACTS...Any fires that develop could spread rapidly. Outdoor burning is not recommended. 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. && $$ UTZ498-150600- /O.EXT.KSLC.FW.W.0008.000000T0000Z-210517T0300Z/ Grand Staircase- 217 PM MDT Fri May 14 2021 ...RED FLAG WARNING NOW IN EFFECT UNTIL 9 PM MDT SUNDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONE 498... * AFFECTED AREA...Fire Weather Zone 498 Grand Staircase. * WINDS...Southwest 10 to 20 mph with gusts up to 35 mph. * RELATIVE HUMIDITY...As low as 5 percent. Poor overnight recoveries are expected. * IMPACTS...Any fires that develop could spread rapidly. Outdoor burning is not recommended. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now...or are imminent. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ UTZ497-150600- /O.EXT.KSLC.FW.W.0008.210515T1700Z-210517T0300Z/ Mojave Desert- 217 PM MDT Fri May 14 2021 ...RED FLAG WARNING NOW IN EFFECT FROM 11 AM SATURDAY TO 9 PM MDT SUNDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONE 497... * AFFECTED AREA...Fire Weather Zone 497 Mojave Desert. * WINDS...South to southwest 15 to 25 mph with gusts up to 40 mph. * RELATIVE HUMIDITY...As low as 9 percent. Poor overnight recoveries are expected. * IMPACTS...Any fires that develop could spread rapidly. Outdoor burning is not recommended. 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. && $$ For more information from NOAA/National Weather Service visit... http://weather.gov/saltlakecity
537 WWUS85 KSLC 150932 RFWSLC URGENT - FIRE WEATHER MESSAGE National Weather Service Salt Lake City UT 332 AM MDT Sat May 15 2021 UTZ495-497-152200- /O.CON.KSLC.FW.W.0008.210515T1700Z-210517T0300Z/ Color Country West Desert-Mojave Desert- 332 AM MDT Sat May 15 2021 ...RED FLAG WARNING REMAINS IN EFFECT FROM 11 AM THIS MORNING TO 9 PM MDT SUNDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONES 495 AND 497... * AFFECTED AREA...Fire Weather Zone 495 Color Country West Desert and Fire Weather Zone 497 Mojave Desert. * WINDS...South to southwest 15 to 25 mph with gusts up to 35 mph. * RELATIVE HUMIDITY...As low as 9 percent with poor overnight recoveries. * IMPACTS...Any fires that develop could spread rapidly. Outdoor burning is not recommended. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now...or are imminent. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ UTZ498-152200- /O.CON.KSLC.FW.W.0008.000000T0000Z-210517T0300Z/ Grand Staircase- 332 AM MDT Sat May 15 2021 ...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM MDT SUNDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONE 498... * AFFECTED AREA...Fire Weather Zone 498 Grand Staircase. * WINDS...Southwest 10 to 20 mph with gusts up to 35 mph. * RELATIVE HUMIDITY...As low as 7 percent with poor overnight recoveries. * IMPACTS...Any fires that develop could spread rapidly. Outdoor burning is not recommended. 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. && $$ For more information from NOAA/National Weather Service visit... http://weather.gov/saltlakecity
623 WWUS85 KSLC 151935 RFWSLC URGENT - FIRE WEATHER MESSAGE National Weather Service Salt Lake City UT 135 PM MDT Sat May 15 2021 UTZ495-497-160600- /O.CON.KSLC.FW.W.0008.000000T0000Z-210517T0300Z/ Color Country West Desert-Mojave Desert- 135 PM MDT Sat May 15 2021 ...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM MDT SUNDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONES 495 AND 497... * AFFECTED AREA...Fire Weather Zone 495 Color Country West Desert and Fire Weather Zone 497 Mojave Desert. * WINDS...South 15 to 25 mph with gusts up to 35 mph. * RELATIVE HUMIDITY...As low as 9 percent. * IMPACTS...Any fires that develop could spread rapidly. Outdoor burning is not recommended. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now...or are imminent. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ UTZ498-160600- /O.CON.KSLC.FW.W.0008.000000T0000Z-210517T0300Z/ Grand Staircase- 135 PM MDT Sat May 15 2021 ...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM MDT SUNDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONE 498... * AFFECTED AREA...Fire Weather Zone 498 Grand Staircase. * WINDS...Southwest 10 to 20 mph with gusts up to 30 mph. * RELATIVE HUMIDITY...As low as 7 percent. * IMPACTS...Any fires that develop could spread rapidly. Outdoor burning is not recommended. 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. && $$ For more information from NOAA/National Weather Service visit... http://weather.gov/saltlakecity
849 WWUS85 KSLC 160445 RFWSLC URGENT - FIRE WEATHER MESSAGE National Weather Service Salt Lake City UT 1045 PM MDT Sat May 15 2021 UTZ495-497-161245- /O.CON.KSLC.FW.W.0008.000000T0000Z-210517T0300Z/ Color Country West Desert-Mojave Desert- 1045 PM MDT Sat May 15 2021 ...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM MDT SUNDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONES 495 AND 497... * AFFECTED AREA...Fire Weather Zone 495 Color Country West Desert and Fire Weather Zone 497 Mojave Desert. * WINDS...South 15 to 25 mph with gusts up to 35 mph. * RELATIVE HUMIDITY...As low as 9 percent. * IMPACTS...Any fires that develop could spread rapidly. Outdoor burning is not recommended. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now...or are imminent. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ UTZ498-161245- /O.CON.KSLC.FW.W.0008.000000T0000Z-210517T0300Z/ Grand Staircase- 1045 PM MDT Sat May 15 2021 ...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM MDT SUNDAY FOR WIND AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONE 498... * AFFECTED AREA...Fire Weather Zone 498 Grand Staircase. * WINDS...Southwest 10 to 20 mph with gusts up to 30 mph. * RELATIVE HUMIDITY...As low as 7 percent. * IMPACTS...Any fires that develop could spread rapidly. Outdoor burning is not recommended. 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. && $$ For more information from NOAA/National Weather Service visit... http://weather.gov/saltlakecity
792 WWUS85 KSLC 160927 RFWSLC URGENT - FIRE WEATHER MESSAGE National Weather Service Salt Lake City UT 327 AM MDT Sun May 16 2021 UTZ495-497-162200- /O.CON.KSLC.FW.W.0008.000000T0000Z-210517T0300Z/ Color Country West Desert-Mojave Desert- 327 AM MDT Sun May 16 2021 ...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM MDT THIS EVENING FOR WIND AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONES 495 AND 497... * AFFECTED AREA...Fire Weather Zone 495 Color Country West Desert and Fire Weather Zone 497 Mojave Desert. * WINDS...South 15 to 25 mph with gusts up to 30 mph. * RELATIVE HUMIDITY...As low as 10 percent. * IMPACTS...Any fires that develop could spread rapidly. Outdoor burning is not recommended. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now...or are imminent. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ UTZ498-162200- /O.CON.KSLC.FW.W.0008.000000T0000Z-210517T0300Z/ Grand Staircase- 327 AM MDT Sun May 16 2021 ...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM MDT THIS EVENING FOR WIND AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONE 498... * AFFECTED AREA...Fire Weather Zone 498 Grand Staircase. * WINDS...Southwest 10 to 20 mph with gusts up to 30 mph. * RELATIVE HUMIDITY...As low as 7 percent. * IMPACTS...Any fires that develop could spread rapidly. Outdoor burning is not recommended. 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. && $$ For more information from NOAA/National Weather Service visit... http://weather.gov/saltlakecity
920 WWUS85 KSLC 162054 RFWSLC URGENT - FIRE WEATHER MESSAGE National Weather Service Salt Lake City UT 254 PM MDT Sun May 16 2021 UTZ495-497-170300- /O.CON.KSLC.FW.W.0008.000000T0000Z-210517T0300Z/ Color Country West Desert-Mojave Desert- 254 PM MDT Sun May 16 2021 ...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM MDT THIS EVENING FOR WIND AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONES 495 AND 497... * AFFECTED AREA...Fire Weather Zone 495 Color Country West Desert and Fire Weather Zone 497 Mojave Desert. * WINDS...South 15 to 25 mph with gusts up to 30 mph. * RELATIVE HUMIDITY...As low as 6 percent. * IMPACTS...Any fires that develop could spread rapidly. Outdoor burning is not recommended. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now...or are imminent. A combination of strong winds...low relative humidity...and warm temperatures can contribute to extreme fire behavior. && $$ UTZ498-170300- /O.CON.KSLC.FW.W.0008.000000T0000Z-210517T0300Z/ Grand Staircase- 254 PM MDT Sun May 16 2021 ...RED FLAG WARNING REMAINS IN EFFECT UNTIL 9 PM MDT THIS EVENING FOR WIND AND LOW RELATIVE HUMIDITY FOR FIRE WEATHER ZONE 498... * AFFECTED AREA...Fire Weather Zone 498 Grand Staircase. * WINDS...Southwest 10 to 20 mph with gusts up to 30 mph. * RELATIVE HUMIDITY...As low as 10 percent. * IMPACTS...Any fires that develop could spread rapidly. Outdoor burning is not recommended. 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
What forecasters said that day
The local office's own words before this red flag warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Salt Lake City, UT wrote its last area forecast discussion before this red flag warning went out at May 12, 3:11 PM MDT, 12 hours 24 minutes earlier.
Area forecast discussion, May 12, 3:11 PM MDT, 12 hours 24 minutes before
Area Forecast Discussion
National Weather Service Salt Lake City UT
311 PM MDT Wed May 12 2021
.SYNOPSIS...
High pressure will rebound across the region mid to late in the
week bringing a warming trend through the end of the week. A low
pressure system cool temperatures to just above normal and bring
slightly unsettled conditions by the weekend.
&&
.SHORT TERM...(Through 12Z Saturday)...
Dry northwest flow will remain in place today before transitioning
to a broad west-southwest flow regime Thursday as a subtle high
pressure ridge builds into the four corners region. As we head
into Friday, a low pressure trough is forecast to wash ashore
across the Pacific Northwest and undergo gradual strengthening as
it traverses southward through California through Friday night. As
this process unfolds, a weak baroclinic zone is forecast to
develop near the ID/UT border Thursday night and remain nearly
stationary through the remainder of the forecast period. This zone
may serve as a focus for shower and thunderstorm initiation. As
was the case yesterday, the GFS remains the most aggressive with
initiating mainly elevated convection near/north of the UT/ID
border beginning Thursday evening with renewed rounds of
convection shown firing along/north of the boundary through the
forecast period. There are hints of this potential beginning to
appear in an increasing number of ensemble members, adding some
weight to the GFS idea. However, the GFS doesn't represent the
current most likely scenario, rather a best-case scenario in terms
of precipitation potential. The NBM does begin to show some PoP
in this area Thursday night, but not high enough to include in
weather grids at this time -- and this looks reasonable. Shower
and thunderstorm development in the vicinity of this boundary does
appear more likely as we head through Friday, and does begin to
appear in the official forecast by Friday afternoon. Given the
dry, sub-cloud layer and antecedent dry soils, gusty, outflow
winds and blowing dust would be primary hazards in association
with this activity. Additional late afternoon and early evening
convective initiation is also becoming increasingly possible
along the Uintas extending southward along higher terrain areas
into central Utah. As southwesterly flow becomes more
unidirectional ahead of the approaching low, anticipate breezy but
sub-advisory level winds to develop in the west and southwest
deserts by Friday afternoon.
.LONG TERM...(After 12Z Saturday)...
An active spring-like pattern will
encompass most of the long term forecast period. The culprit behind
this active pattern will be a slow moving closed low across the
desert southwest through the upcoming weekend and into the first
part of next week. The long term discussion will focus on the
expected impacts over the weekend and into next week.
Models have come into agreement and now support a closed low
developing across northern California with a good grouping of the
models digging this low south to southeast across central California
on Saturday. Downstream of this low pressure center, ridging begins
to intensify across central Colorado and H5 height rises are noted
across Utah Saturday afternoon. With a deepening low across
California and this ridge axis intrusion, Utah will see a tightening
pressure gradient as H7 winds increase to around 30-35kts by the
afternoon. Expect breezy conditions across much of southwestern and
southern Utah. The concern across these areas in Utah, is the
combination of gusty winds and dry conditions creating some fire
weather concerns on Saturday. (See Fire Weather discussion below.
Some areas of blowing dust will also be possible across southern
Utah and portions of the west desert Saturday afternoon and into the
early evening before the winds begin to decrease.
While much of the southern half of Utah will remain dry, diurnally
driven convection will be possible across northern Utah as we head
into late Saturday afternoon. A band of 500-800J/kg CAPE along the
higher terrain and the addition of some mid level moisture should be
sufficient enough to allow a few isolated thunderstorms to develop.
Based on model sounding profiles across the area, any convection
that does develop will be shallow with a dry sub cloud layer beneath
the LCL (Base of the cloud). Primary hazards with this type of
convection will be strong downburst winds and very small hail. There
is also the potential for a few cloud-to-ground lightning strikes
associated with the stronger cores that will pose an additional
hazard.
This pattern will persist through the weekend and into the
first part of next week as the area of low pressure slowly moves
across the desert southwest. Winds will decrease across southern
Utah and should continue to see mostly dry conditions, while diurnal
convection will continue to develop across the higher terrain across
northern Utah during the afternoon hours Sunday-Tuesday.
Temperatures will stay consistent and run above normal through the
weekend and into next week.
Looking ahead toward the latter part of the long term (Day 7) an
upstream trough forecast to move into the intermountain west has a
lot of uncertainty across the model outputs so the forecast remains
locked to the NBM initialized forecast.
&&
.AVIATION...
KSLC...Light and diurnal winds are expected this forecast period.
Winds are expected to shift out of the southeast around 04Z this
evening with winds back out of the northwest late tomorrow
morning. Skies will remain mostly clear with only high cloud decks
forecast.
Rest of Utah and southwest Wyoming...VFR ceilings and visibility are
forecast under high pressure tonight and tomorrow. Look for
generally light winds though some breezy winds are possible at EVW
and BCE this afternoon and again tomorrow afternoon.
&&
.FIRE WEATHER...
Increasingly dry and warmer conditions will
continue through Thursday as a weak ridge of high pressure moves
across the area. Temperatures will achieve highs of 10-15 degrees
above climatological normals by Thursday, with only very slight
cooling through the weekend. An area of low pressure is forecast
to develop across California on Friday, and very slowly move south
and east towards southern Nevada on Sunday. This process will
force winds to turn southwesterly, especially across western and
southwestern deserts by Friday. Although minimum relative humidity
will reach critically low values across southern Utah on Friday,
winds are forecast to largely remain below critical values for
zones 497 and 498, except for isolated areas. On Saturday, winds
will continue to increase, and are forecast to reach critical
values by late Saturday morning with little change in humidity. As
a result have issued a Fire Weather Watch for zones 497 and 498
for the combination of gusty winds and low relative humidity from
late Saturday morning through early Saturday evening. With that
said, critically low relative humidity and critically strong wind
gusts will be found across much of southwest and southern Utah,
leading to elevated fire weather conditions. Isolated
thunderstorms are expected across northern UT and the Unitas by
Friday afternoon with somewhat better chances across northern Utah
on Saturday. Given the dry airmass in place, an isolated dry storm
cannot be ruled out. For Sunday, breezy conditions are likely to
continue, particularly across southern and southwestern Utah.
Relative humidity is expected to begin to increase on Sunday as
the low pressure system approaches. Given the anticipated increase
in humidity for Sunday, opted to not issue another Fire Weather
Watch for zones 497 and 498, but this will need to be monitored
going forward. The low is then forecast to track near or just
south of southern Utah on Monday, forcing and increase in shower
and thunderstorm chances along with an accompanying increase in
humidity. Winds should decrease greatly outside of shower and
thunderstorm activity given the close proximity of the low.
&&
.SLC WATCHES/WARNINGS/ADVISORIES...
UT...Fire Weather Watch from Saturday morning through Saturday
evening for UTZ497-498.
WY...None.
&&
SHORT TERM...Van Cleave/ADeSmet
LONG TERM...Woodward
AVIATION... Webber/NDeSmet
FIRE WEATHER...Van Cleave/ADeSmet
For more information from NOAA's National Weather Service visit...
http://weather.gov/saltlakecity
For frequently asked questions about the Area Forecast Discussion
visit...
http://weather.gov/saltlakecity/general/afd_faqs.phpNearby
Red Flag Warnings in Utah, 2021Every red flag warning in 2021
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.