Alert archive / Utah / Flash Flood Warnings in 2021

Flash Flood Warning 81, NWS Salt Lake City, UT

August 1, 2021Iron County, Utah

NWS Salt Lake City, UT issued this flash flood warning at Aug 1, 2021, 3:35 PM MDT for Iron 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, 3:35 PM MDT (21:35 UTC)
Expired
Aug 1, 2021, 6:45 PM MDT
In force
3 hr
Issued by
NWS Salt Lake City, UT
Area
Storm-based polygon
Emergency
Flash flood emergency
Damage threat
Considerable
Flood severity
None

County Iron County, UT

The radar

The Cedar City radar (KICX), 27 km from the middle of the area, began a volume at 21:37 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, 4:19 PM MDTFLASH FLOODCedar City, UTMULTIPLE REPORTS OF WATER FLOWING THROUGH ROADWAYS. WATER ERODED A PORTION OF A ROAD AND DAMAGED IT.
Aug 1, 4:19 PM MDTFLASH FLOODEnoch, UTCOUNTY EMERGENCY MANAGEMENT REPORTS 100 HOMES UNDERWATER IN THE CITY OF ENOCH. FIDDLERS CANYON IS UNDERWATER. PORTIONS OF I-15 ARE CLOSED.

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

The nearest sounding before it

Las Vegas, NV (KVEF), launched 12:00Z, 9.6 hours before the alert went out and 271 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 2021-08-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 680 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, Las Vegas, NV at 12:00Z on 2021-08-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -1 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
680 J/kg
Mixed-layer CIN
-99 J/kg
Mixed-layer LCL
1983 m above ground
0-6 km bulk shear
16 kt
0-1 km storm-relative helicity
-1 m²/s²
0-3 km storm-relative helicity
27 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

407 
WGUS55 KSLC 012135
FFWSLC
UTC021-020045-
/O.NEW.KSLC.FF.W.0081.210801T2135Z-210802T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

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

The National Weather Service in Salt Lake City has issued a

* Flash Flood Warning for...
  Central Iron County in southern Utah...

* Until 645 PM MDT.

* At 335 PM MDT, Doppler radar indicated 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...Radar.

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

* Some locations that will experience flash flooding include...
  Cedar City, Enoch and Summit.

This includes the following highways...
	Interstate 15 between mile markers 60 and 69.
	Utah Route 56 near mile marker 61.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be aware of your surroundings and do not drive on flooded roads.

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.

&&

LAT...LON 3786 11311 3788 11295 3768 11296 3766 11308

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

$$

CRK
5 follow-up statements
149 
WGUS75 KSLC 012206
FFSSLC

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

UTC021-020045-
/O.CON.KSLC.FF.W.0081.000000T0000Z-210802T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Iron UT-
406 PM MDT Sun Aug 1 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 645 PM MDT THIS 
EVENING FOR CENTRAL IRON COUNTY...

At 406 PM MDT, local law enforcement reported flash flooding in 
Enoch, Summit and Cedar City. Between 1 and 2 inches of rain have 
fallen. Flash flooding is already occurring.  DO NOT DRIVE INTO 
FLOODED AREAS.

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

SOURCE...Law enforcement reported.

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

Some locations that will experience flash flooding include...
  Cedar City, Enoch and Summit.

This includes the following highways...
	Interstate 15 between mile markers 58 and 69.
	Utah Route 56 near mile marker 61.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be aware of your surroundings and do not drive on flooded roads.

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.

&&

LAT...LON 3786 11311 3788 11295 3768 11296 3766 11308

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

$$

CRK
577 
WGUS75 KSLC 012219
FFSSLC

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

UTC021-020045-
/O.CON.KSLC.FF.W.0081.000000T0000Z-210802T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Iron UT-
419 PM MDT Sun Aug 1 2021

...FLASH FLOOD EMERGENCY FOR ENOCH AND CEDAR CITY...

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 645 PM MDT THIS 
EVENING FOR CENTRAL IRON COUNTY...

At 419 PM MDT, local law enforcement reported thunderstorms 
producing heavy rain in Enoch, Summit and Cedar City. Between 1 and 
2 inches of rain have fallen. Flash flooding is already occurring.

This is a FLASH FLOOD EMERGENCY for Enoch and Cedar City. This is a 
PARTICULARLY DANGEROUS SITUATION. SEEK HIGHER GROUND NOW!

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

SOURCE...Law enforcement reported.

IMPACT...This is a PARTICULARLY DANGEROUS SITUATION. SEEK HIGHER
         GROUND NOW! Life threatening flash flooding of low water
         crossings, small creeks and streams, urban areas,
         highways, streets and underpasses.

Some locations that will experience flash flooding include...
  Cedar City, Enoch and Summit.

This includes the following highways...
	Interstate 15 between mile markers 58 and 69.
	Utah Route 56 near mile marker 61.

Local emergency management reports many homes underwater and water 
rescues are being performed.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to higher ground now! This is an extremely dangerous and 
life-threatening situation. Do not attempt to travel unless you are 
fleeing an area subject to flooding or under an evacuation order.

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

Be aware of your surroundings and do not drive on flooded roads.

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.

&&

LAT...LON 3786 11311 3788 11295 3768 11296 3766 11308

FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CATASTROPHIC

$$

CRK
793 
WGUS75 KSLC 012354
FFSSLC

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

UTC021-020045-
/O.CON.KSLC.FF.W.0081.000000T0000Z-210802T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Iron UT-
554 PM MDT Sun Aug 1 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 645 PM MDT THIS 
EVENING FOR CENTRAL IRON COUNTY...

At 554 PM MDT, local law enforcement reported thunderstorms 
producing heavy rain in Enoch, Summit and Cedar City. Between 1.5 
and 3 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,
         urban areas, highways, streets and underpasses.

Some locations that will experience flash flooding include...
  Cedar City, Enoch and Summit.

This includes the following highways...
	Interstate 15 between mile markers 58 and 69.
	Utah Route 56 near mile marker 61.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be aware of your surroundings and do not drive on flooded roads.

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.

&&

LAT...LON 3786 11311 3788 11295 3768 11296 3766 11308

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

$$

CRK
514 
WGUS75 KSLC 020016
FFSSLC

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

UTC021-020045-
/O.CON.KSLC.FF.W.0081.000000T0000Z-210802T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Iron UT-
616 PM MDT Sun Aug 1 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 645 PM MDT THIS 
EVENING FOR CENTRAL IRON COUNTY...

At 616 PM MDT, Doppler radar indicated thunderstorms producing heavy 
rain in Enoch, Summit and Cedar City. Between 1.5 and 3 inches of 
rain have fallen. Additional rainfall amounts of 0.25 to 0.75 inches 
are possible in the warned area. Flash flooding is already occurring.

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...
  Cedar City, Enoch and Summit.

This includes the following highways...
	Interstate 15 between mile markers 58 and 69.
	Utah Route 56 near mile marker 61.

An additional period of moderate to heavy rainfall will cross Cedar 
City, Enoch and Summit over the next 30 minutes to 1 hour.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Be aware of your surroundings and do not drive on flooded roads.

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.

&&

LAT...LON 3786 11311 3788 11295 3768 11296 3766 11308

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

$$

CRK
891 
WGUS75 KSLC 020039
FFSSLC

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

UTC021-020049-
/O.EXP.KSLC.FF.W.0081.000000T0000Z-210802T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Iron UT-
639 PM MDT Sun Aug 1 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 645 PM MDT THIS EVENING FOR 
CENTRAL IRON COUNTY...

The heavy rain has ended. Please continue to heed remaining road 
closures.  Enhanced runoff will continue through late evening. Do 
not enter flood areas. Driving into flooded areas is especially 
dangerous at night.

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

LAT...LON 3786 11311 3788 11295 3768 11296 3766 11308

$$

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, 1:35 PM MDTFlash Flood Warning Considerable damage threatSLCWayne3 hr
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, 3:47 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.