Alert archive / Utah / Flash Flood Warnings in 2021

Flash Flood Warning 52, NWS Salt Lake City, UT

July 26, 2021Garfield County, Utah

NWS Salt Lake City, UT issued this flash flood warning at Jul 26, 2021, 2:45 PM MDT for Garfield County, Utah. It was in force for 4 hr. 1 report 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: Jul 26, 2021, 2:45 PM MDT (20:45 UTC)
Expired: Jul 26, 2021, 6:45 PM MDT
In force: 4 hr
Issued by: NWS Salt Lake City, UT
Area: Storm-based polygon
Damage threat: Considerable
Flood severity: None

County Garfield County, UT

The radar

The Cedar City radar (KICX), 134 km from the middle of the area, began a volume at 20:48 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.

What was reported inside it

Time	Report	Where	Remark
Jul 26, 5:15 PM MDT	FLASH FLOOD	2 Ne Escalante, UT	ESCALANTE RIVER GAUGE ROSE FROM 3 CFS TO 1060 CFS. LSR TIME IS OF THE PEAK, BUT RIVER WAS ABOVE 500 CFS BETWEEN 1530 AND 1930 MDT.

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

The nearest sounding before it

Flgstf/Belemont, AZ (KFGZ), launched 12:00Z, 8.8 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.

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: 20 J/kg
Mixed-layer CIN: -105 J/kg
Mixed-layer LCL: 954 m above ground
0-6 km bulk shear: 15 kt
0-1 km storm-relative helicity: 30 m²/s²
0-3 km storm-relative helicity: 37 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

316 
WGUS55 KSLC 262045
FFWSLC
UTC017-270045-
/O.NEW.KSLC.FF.W.0052.210726T2045Z-210727T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Salt Lake City UT
245 PM MDT Mon Jul 26 2021

The National Weather Service in Salt Lake City has issued a

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

* Until 645 PM MDT.

* At 245 PM MDT, Doppler radar indicated thunderstorms producing 
  heavy rain over the upper Escalante River Headwaters. Between 0.5 
  and 1 inch of rain has fallen. Flash flooding is ongoing or 
  expected to begin shortly, specifically for the Escalante River 
  Canyon just east of the town of Escalante and points downstream on 
  the Escalante River.

  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...
  Escalante.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3784 11158 3788 11129 3789 11126 3781 11118
      3768 11115 3766 11125 3770 11130 3775 11143
      3776 11157

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

$$

GM

1 follow-up statement

103 
WGUS75 KSLC 270049
FFSSLC

Flash Flood Statement
National Weather Service Salt Lake City UT
649 PM MDT Mon Jul 26 2021

UTC017-270059-
/O.EXP.KSLC.FF.W.0052.000000T0000Z-210727T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Garfield UT-
649 PM MDT Mon Jul 26 2021

...FLASH FLOOD WARNING HAS EXPIRED FOR CENTRAL GARFIELD COUNTY...

The Escalante River will retain elevated flows into the overnight 
hours tonight, but the USGS Escalante River gauge indicates peak 
flows have already occurred, and the flash flood is beginning the 
recede. The heavy rain has ended, and no additional flash flooding 
is anticipated at this time.

LAT...LON 3784 11158 3788 11129 3789 11126 3781 11118
      3768 11115 3766 11125 3770 11130 3775 11143
      3776 11157

$$

GM

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 25, 6:06 PM MDT	Special Weather Statement	SLC	Washington	39 min
Jul 25, 6:16 PM MDT	Special Weather Statement	SLC	Washington	44 min
Jul 26, 3:37 AM MDT	Flash Flood Watch	SLC	Beaver, Garfield, Iron, Kane, Piute, Washington and 1 more	20 hr
Jul 26, 1:13 PM MDT	Flash Flood Warning Considerable damage threat	SLC	Kane, Washington	3 hr
Jul 26, 1:37 PM MDT	Severe Thunderstorm Warning	SLC	Washington	23 min
Jul 26, 1:40 PM MDT	Flash Flood Warning Considerable damage threat	SLC	Garfield	3 hr
Jul 26, 1:47 PM MDT	Special Weather Statement	SLC	Piute	43 min
Jul 26, 2:00 PM MDT	Special Weather Statement	SLC	Washington	45 min
Jul 26, 2:07 PM MDT	Areal Flood Advisory	SLC	Washington	53 min
Jul 26, 2:12 PM MDT	Areal Flood Advisory	SLC	Iron	2 hr
Jul 26, 2:35 PM MDT	Flash Flood Warning Considerable damage threat	SLC	Iron	115 min
Jul 26, 2:53 PM MDT	Flash Flood Warning Considerable damage threat	SLC	Iron, Washington	3 hr
Jul 26, 3:01 PM MDT	Severe Thunderstorm Warning	SLC	Beaver, Iron	29 min
Jul 26, 3:07 PM MDT	Severe Thunderstorm Warning	SLC	Beaver, Iron	23 min
Jul 26, 3:20 PM MDT	Severe Thunderstorm Warning	SLC	Beaver, Iron	2 min
Jul 26, 3:26 PM MDT	Special Weather Statement	SLC	Washington	49 min
Jul 26, 3:30 PM MDT	Severe Thunderstorm Warning	SLC	Washington	30 min
Jul 26, 3:32 PM MDT	Areal Flood Advisory	SLC	Washington	118 min
Jul 26, 3:32 PM MDT	Flash Flood Warning Considerable damage threat	SLC	Beaver	3 hr
Jul 26, 4:00 PM MDT	Severe Thunderstorm Warning	SLC	Washington	30 min
Jul 26, 4:34 PM MDT	Special Weather Statement	SLC	Washington	41 min
Jul 26, 4:55 PM MDT	Special Weather Statement	SLC	Beaver	50 min
Jul 26, 5:30 PM MDT	Flash Flood Warning Considerable damage threat	SLC	Kane	6 hr

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.