Alert archive / Utah / Flash Flood Warnings in 2021

Flash Flood Warning 79, NWS Salt Lake City, UT

August 1, 2021Wayne County, Utah

NWS Salt Lake City, UT issued this flash flood warning at Aug 1, 2021, 1:35 PM MDT for Wayne County, Utah. It was in force for 3 hr. 2 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Aug 1, 2021, 1:35 PM MDT (19:35 UTC)
Expired
Aug 1, 2021, 4:45 PM MDT
In force
3 hr
Issued by
NWS Salt Lake City, UT
Area
Storm-based polygon
Damage threat
Considerable
Flood severity
None

County Wayne County, UT

The radar

The Cedar City radar (KICX), 147 km from the middle of the area, began a volume at 19:38 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
Aug 1, 2:15 PM MDTFLASH FLOOD4 Ene Torrey, UTCAPITOL REEF PARK OFFICIALS AND LAW ENFORCEMENT REPORT FLASH FLOODING ON SULPHUR CREEK AND FREMONT WITH MUDDY CONDITIONS ON SCENIC DRIVE. INITIAL FLOOD WAVE THROUGH SULPHUR CREEK CONTAINED BLACK BOULDERS. FLASH FLOODING BEGAN AT FREMONT AT 1415 HRS.
Aug 1, 3:15 PM MDTFLASH FLOOD4 Ene Torrey, UTCAPITOL REEF PARK OFFICIALS AND LAW ENFORCEMENT REPORT FLASH FLOODING ON SULFUR CREEK AND FREMONT WITH MUDDY CONDITIONS ON SCENIC DRIVE. FLASH FLOODING BEGAN AT FREMONT AT 1415 HOURS.

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

The nearest sounding before it

Grand Junction, CO (KGJT), launched 12:00Z, 7.6 hours before the alert went out and 273 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, Grand Junction, CO at 12:00Z on 2021-08-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 3 joules per kilogram.LCLLFCEL10008507005003002001001 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, Grand Junction, CO at 12:00Z on 2021-08-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 28 square meters per square second.1939Sfc1 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
3 J/kg
Mixed-layer CIN
-195 J/kg
Mixed-layer LCL
1536 m above ground
0-6 km bulk shear
8 kt
0-1 km storm-relative helicity
28 m²/s²
0-3 km storm-relative helicity
12 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

763 
WGUS55 KSLC 011935
FFWSLC
UTC055-012245-
/O.NEW.KSLC.FF.W.0079.210801T1935Z-210801T2245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Salt Lake City UT
135 PM MDT Sun Aug 1 2021

The National Weather Service in Salt Lake City has issued a

* Flash Flood Warning for...
  Southwestern Wayne County in southern Utah...

* Until 445 PM MDT.

* At 135 PM MDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Flash flooding is ongoing or 
  expected to begin shortly.

  HAZARD...Life threatening flash flooding. Thunderstorms
           producing flash flooding.

  SOURCE...Radar.

  IMPACT...Life threatening flash flooding of creeks and streams,
           urban areas, highways, streets and underpasses.

* Some locations that will experience flash flooding include...
  Capitol Reef National Park, Loa, Bicknell, Torrey, Teasdale, 
  Lyman, Fremont and Fruita.

Additional locations include the Fremont River from near Loa to near 
Caineville, Sulfur Creek, Sunglow Canyon, Coahb Canyon, Grand Wash 
and the Scenic Drive.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Remain alert for flooding even in locations not receiving rain. Dry 
washes, streams, and rivers can become raging killer currents in a 
matter of minutes, even from distant rainfall.

Flooding is occurring or is imminent. It is important to know where 
you are relative to streams, rivers, or creeks which can become 
killers in heavy rains. Campers and hikers should avoid streams or 
creeks.

&&

LAT...LON 3847 11159 3840 11133 3828 11103 3820 11129
      3824 11175 3835 11179

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

CRK
3 follow-up statements
977 
WGUS75 KSLC 012038
FFSSLC

Flash Flood Statement
National Weather Service Salt Lake City UT
238 PM MDT Sun Aug 1 2021

UTC055-012245-
/O.CON.KSLC.FF.W.0079.000000T0000Z-210801T2245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Wayne UT-
238 PM MDT Sun Aug 1 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 445 PM MDT THIS 
AFTERNOON FOR SOUTHWESTERN WAYNE COUNTY...

At 238 PM MDT, trained weather spotters reported thunderstorms 
producing heavy rain across the warned area. Between 1 and 2 inches 
of rain have fallen. Flash flooding is ongoing or expected to begin 
shortly.

HAZARD...Life threatening flash flooding. Thunderstorms producing
         flash flooding.

SOURCE...Trained spotters reported.

IMPACT...Life threatening flash flooding of creeks and streams,
         urban areas, highways, streets and underpasses.

Some locations that will experience flash flooding include...
  Capitol Reef National Park, Loa, Bicknell, Torrey, Teasdale, 
  Lyman, Fremont and Fruita.

Additional locations include the Fremont River from near Loa to near 
Caineville, Sulfur Creek, Sunglow Canyon, Coahb Canyon, Grand Wash 
and the Scenic Drive.

A trained spotter in Torrey reported 1.5 inches of rain in an hour.  
This will cause significant flash flooding in the warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Remain alert for flooding even in locations not receiving rain. Dry 
washes, streams, and rivers can become raging killer currents in a 
matter of minutes, even from distant rainfall.

Flooding is occurring or is imminent. It is important to know where 
you are relative to streams, rivers, or creeks which can become 
killers in heavy rains. Campers and hikers should avoid streams or 
creeks.

&&

LAT...LON 3847 11159 3840 11133 3828 11103 3820 11129
      3824 11175 3835 11179

FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

CRK
893 
WGUS75 KSLC 012122
FFSSLC

Flash Flood Statement
National Weather Service Salt Lake City UT
322 PM MDT Sun Aug 1 2021

UTC055-012245-
/O.CON.KSLC.FF.W.0079.000000T0000Z-210801T2245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Wayne UT-
322 PM MDT Sun Aug 1 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 445 PM MDT THIS 
AFTERNOON FOR SOUTHWESTERN WAYNE COUNTY...

At 322 PM MDT, local law enforcement reported flash flooding along 
the Fremont River and Sulfur Creek. Between 1 and 2 inches of rain 
have fallen. Flash flooding is already occurring.

HAZARD...Life threatening flash flooding. Thunderstorms producing
         flash flooding.

SOURCE...Law enforcement reported.

IMPACT...Life threatening flash flooding of creeks and streams,
         dry washes, highways, streets and underpasses.

Some locations that will experience flash flooding include...
  Capitol Reef National Park, Loa, Bicknell, Torrey, Teasdale, 
  Lyman, Fremont and Fruita.

Additional locations include the Fremont River from near Loa to near 
Caineville, Sulfur Creek, Sunglow Canyon, Coahb Canyon, Grand Wash 
and the Scenic Drive.

Law enforcement reported mud across the scenic drive. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Remain alert for flooding even in locations not receiving rain. Dry 
washes, streams, and rivers can become raging killer currents in a 
matter of minutes, even from distant rainfall.

Flooding is occurring or is imminent. It is important to know where 
you are relative to streams, rivers, or creeks which can become 
killers in heavy rains. Campers and hikers should avoid streams or 
creeks.

&&

LAT...LON 3847 11159 3840 11133 3828 11103 3820 11129
      3824 11175 3835 11179

FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

CRK
160 
WGUS75 KSLC 012239
FFSSLC

Flash Flood Statement
National Weather Service Salt Lake City UT
439 PM MDT Sun Aug 1 2021

UTC055-012249-
/O.EXP.KSLC.FF.W.0079.000000T0000Z-210801T2245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Wayne UT-
439 PM MDT Sun Aug 1 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 445 PM MDT THIS AFTERNOON FOR 
SOUTHWESTERN WAYNE COUNTY...

Heavy rainfall has ended for the time being.  Enhanced runoff will 
continue in normally dry washes and slot canyons.  Use extreme 
caution in these areas through the evening.

A Flash Flood Watch remains in effect until 1200 AM MDT Monday for 
portions of central Utah, northern Utah, southern Utah and southwest 
Utah.

LAT...LON 3847 11159 3840 11133 3828 11103 3820 11129
      3824 11175 3835 11179

$$

CRK

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 31, 6:07 PM MDTSpecial Weather StatementSLCTooele23 min
Jul 31, 6:09 PM MDTSpecial Weather StatementSLCWashington51 min
Jul 31, 6:22 PM MDTFlash Flood Warning Considerable damage threatSLCWashington4 hr
Jul 31, 6:26 PM MDTSpecial Weather StatementSLCTooele34 min
Jul 31, 6:47 PM MDTSpecial Weather StatementSLCTooele28 min
Jul 31, 6:58 PM MDTSevere Thunderstorm WarningSLCTooele32 min
Jul 31, 7:06 PM MDTSpecial Weather StatementSLC24 min
Jul 31, 7:44 PM MDTSpecial Weather StatementSLC46 min
Jul 31, 7:51 PM MDTSpecial Weather StatementSLCTooele39 min
Jul 31, 8:03 PM MDTSpecial Weather StatementSLCSalt Lake27 min
Jul 31, 8:28 PM MDTSpecial Weather StatementSLCDavis47 min
Jul 31, 8:30 PM MDTSpecial Weather StatementSLC30 min
Jul 31, 8:43 PM MDTSpecial Weather StatementSLCDavis32 min
Jul 31, 8:52 PM MDTSpecial Weather StatementSLCDavis38 min
Jul 31, 9:11 PM MDTSpecial Weather StatementSLCDavis49 min
Jul 31, 9:33 PM MDTSpecial Weather StatementSLCDavis27 min
Aug 1, 3:21 AM MDTFlash Flood WatchSLCBeaver, Carbon, Duchesne, Emery, Garfield, Iron and 13 more21 hr
Aug 1, 12:47 PM MDTFlash Flood Warning Considerable damage threatSLCGarfield3 hr
Aug 1, 1:23 PM MDTAreal Flood AdvisorySLCSevier112 min
Aug 1, 1:58 PM MDTFlash Flood Warning Considerable damage threatSLCDuchesne, Wasatch3 hr
Aug 1, 2:52 PM MDTSevere Thunderstorm WarningSLCJuab, Tooele38 min
Aug 1, 2:59 PM MDTAreal Flood AdvisorySLCEmery, Sevier2 hr
Aug 1, 3:25 PM MDTAreal Flood AdvisorySLCIron11 min
Aug 1, 3:35 PM MDTFlash Flood Warning EmergencyConsiderable damage threatSLCIron3 hr
Aug 1, 3:47 PM MDTSpecial Weather StatementSLCIron43 min
Aug 1, 3:55 PM MDTSpecial Weather StatementSLCWayne50 min
Aug 1, 3:57 PM MDTSpecial Weather StatementSLCJuab48 min
Aug 1, 4:11 PM MDTSevere Thunderstorm WarningSLCJuab, Tooele34 min
Aug 1, 4:16 PM MDTSpecial Weather StatementSLCWashington44 min
Aug 1, 4:50 PM MDTSpecial Weather StatementSLCTooele40 min
Aug 1, 5:04 PM MDTAreal Flood AdvisorySLCIron, Washington116 min
Aug 1, 5:15 PM MDTSpecial Weather StatementSLCTooele30 min
Aug 1, 5:30 PM MDTSevere Thunderstorm WarningSLCBox Elder45 min
Aug 1, 5:31 PM MDTSpecial Weather StatementSLCPiute44 min
Aug 1, 5:40 PM MDTSpecial Weather StatementSLCSalt Lake50 min
Aug 1, 5:51 PM MDTSpecial Weather StatementSLCTooele39 min

Nearby

Flash Flood Warnings in Utah, 2021Every flash flood 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.