Alert archive / Utah / Flash Flood Warnings in 2021

Flash Flood Warning 128, NWS Salt Lake City, UT

September 1, 2021Garfield County, Wayne County, Utah

NWS Salt Lake City, UT issued this flash flood warning at Sep 1, 2021, 4:59 PM MDT for Garfield County, Wayne County, Utah. It was in force for 2 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: Sep 1, 2021, 4:59 PM MDT (22:59 UTC)
Expired: Sep 1, 2021, 7:25 PM MDT
In force: 2 hr
Issued by: NWS Salt Lake City, UT
Area: Storm-based polygon
Damage threat: Considerable
Flood severity: None

Counties Garfield County, UT, Wayne County, UT

The radar

The Cedar City radar (KICX), 160 km from the middle of the area, began a volume at 23:00 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

Time	Report	Where	Remark
Sep 1, 4:59 PM MDT	FLASH FLOOD	2 Ene Capitol Reef Np, UT	CAPITOL REEF NATIONAL PARK REPORTED 6 INCHES OF WATER FLOWING ACROSS SR-24 IN SEVERAL LOCATIONS EAST OF FRUITA.
Sep 1, 5:07 PM MDT	FLASH FLOOD	1 W Capitol Reef Np, UT	UDOT REPORTED 6 INCHES OF WATER FLOWING ACROSS SR-24 BETWEEN MILE MARKERS 81 AND 84.

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, 11.0 hours before the alert went out and 258 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 6 J/kg
Mixed-layer CIN: -96 J/kg
Mixed-layer LCL: 1726 m above ground
0-6 km bulk shear: 34 kt
0-1 km storm-relative helicity: -24 m²/s²
0-3 km storm-relative helicity: 139 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

744 
WGUS55 KSLC 012259
FFWSLC
UTC017-055-020200-
/O.NEW.KSLC.FF.W.0128.210901T2259Z-210902T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Salt Lake City UT
459 PM MDT Wed Sep 1 2021

The National Weather Service in Salt Lake City has issued a

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

* Until 800 PM MDT.

* At 459 PM MDT, Capitol Reef National Park officials reported heavy 
  rain over the park. Between 0.2 and 0.3 inches of rain have 
  fallen. Additional rainfall amounts of 0.2 to 0.3 inches are 
  possible in the warned area. Flash flooding is already occurring 
  with water running over Highway 24 east of Fruita.

  HAZARD...Life threatening flash flooding. Heavy rain producing
           flash flooding.

  SOURCE...Capitol Reef National Park officials 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, Fruita and Caineville.

This includes the following highways...
	Utah Route 24 between mile markers 71 and 102.

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.

&&

LAT...LON 3842 11153 3838 11095 3817 11093 3808 11105
      3807 11121 3829 11134 3833 11152

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

$$

Church

1 follow-up statement

639 
WGUS75 KSLC 020125
FFSSLC

Flash Flood Statement
National Weather Service Salt Lake City UT
725 PM MDT Wed Sep 1 2021

UTC017-055-020135-
/O.CAN.KSLC.FF.W.0128.000000T0000Z-210902T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Garfield UT-Wayne UT-
725 PM MDT Wed Sep 1 2021

...FLASH FLOOD WARNING IS CANCELLED FOR NORTHEASTERN GARFIELD AND 
SOUTHWESTERN WAYNE COUNTIES...

Flood waters have receded. The heavy rain has ended. Flooding is no 
longer expected to pose a threat. Please continue to heed remaining 
road closures.

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

LAT...LON 3842 11153 3838 11095 3817 11093 3808 11105
      3807 11121 3829 11134 3833 11152

$$

Church

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 31, 6:17 PM MDT	Special Weather Statement	SLC	Tooele	43 min
Aug 31, 7:22 PM MDT	Special Weather Statement	SLC	Davis	38 min
Sep 1, 1:37 AM MDT	Areal Flood Advisory	SLC	Washington	3 hr
Sep 1, 8:21 AM MDT	Flash Flood Warning Considerable damage threat	SLC	Kane, Washington	3 hr
Sep 1, 3:25 PM MDT	Special Weather Statement	SLC	Iron	35 min

Nearby

Flash Flood Warnings in Utah, 2021 Every 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.