Alert archive / Utah / Flash Flood Warnings in 2021

Flash Flood Warning 1, NWS Salt Lake City, UT

June 29, 2021Garfield County, Utah

NWS Salt Lake City, UT issued this flash flood warning at Jun 29, 2021, 1:53 PM MDT for Garfield County, Utah. It was in force for 3 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: Jun 29, 2021, 1:53 PM MDT (19:53 UTC)
Expired: Jun 29, 2021, 5:00 PM MDT
In force: 3 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), 121 km from the middle of the area, began a volume at 19:58 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
Jun 29, 3:30 PM MDT	FLASH FLOOD	8 E Escalante, UT	CORRECTING A PREVIOUSLY-ISSUED LOCAL STORM REPORT FOR LOCATION. AT APPROXIMATELY 330 PM ON JUNE 29TH, FLASH FLOODING WAS OBSERVED AT THE SR12 OVERPASS OF THE ESCALANTE RIVER. ADDITIONAL REPORTS OF FLASH FLOODING WERE OBSERVED UPSTREAM. OTHER REPORTS INCLUDED E

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, 7.9 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: 225 J/kg
Mixed-layer CIN: -162 J/kg
Mixed-layer LCL: 1570 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: -75 m²/s²
0-3 km storm-relative helicity: -28 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.1

Open this sounding in Storm Lab

The text

As transmitted.

968 
WGUS55 KSLC 291953
FFWSLC
UTC017-292300-
/O.NEW.KSLC.FF.W.0001.210629T1953Z-210629T2300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Salt Lake City UT
153 PM MDT Tue Jun 29 2021

The National Weather Service in Salt Lake City has issued a

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

* Until 500 PM MDT.

* At 153 PM MDT, Doppler radar indicated thunderstorms producing 
  heavy rain in Death Hollow Canyon, Micro Death Hollow Canyon, and 
  the Upper Escalante River Canyon. Between 0.5 and 1 inch of rain 
  has fallen. Additional rainfall amounts of 0.25 to 0.5 inches are 
  possible in 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...
  mainly rural areas of Southwestern Garfield County

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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 3781 11156 3784 11149 3777 11142 3776 11146
      3774 11154

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

$$

GM

2 follow-up statements

720 
WGUS75 KSLC 292141
FFSSLC

Flash Flood Statement
National Weather Service Salt Lake City UT
341 PM MDT Tue Jun 29 2021

UTC017-292300-
/O.CON.KSLC.FF.W.0001.000000T0000Z-210629T2300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Garfield UT-
341 PM MDT Tue Jun 29 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 5 PM MDT THIS 
AFTERNOON FOR SOUTHWESTERN GARFIELD COUNTY...

At 341 PM MDT, Trained weather spotters from the Escalante National 
Recreation area's visitor center reported flash flooding along the 
Escalante River from the town of Escalante east through the 
Escalante River Canyon area. Flooding is also occurring in Alvey 
Wash. Between 0.75 and 1.75 inches of rain have fallen. Flash 
flooding is already occurring.

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...
  The Escalante River Canyon east of the town of Escalante.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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 3781 11156 3784 11149 3777 11142 3776 11146
      3774 11154

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

$$

GM

620 
WGUS75 KSLC 292259
FFSSLC

Flash Flood Statement
National Weather Service Salt Lake City UT
459 PM MDT Tue Jun 29 2021

UTC017-292309-
/O.EXP.KSLC.FF.W.0001.000000T0000Z-210629T2300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Garfield UT-
459 PM MDT Tue Jun 29 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 5 PM MDT THIS AFTERNOON FOR 
SOUTHWESTERN GARFIELD COUNTY...

The heavy rain has ended. Elevated flows continue in the Escalante 
River Canyon, but will continue to recede over the next few hours.

LAT...LON 3781 11156 3784 11149 3777 11142 3776 11146
      3774 11154

$$

GM

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 29, 2:11 PM MDT	Flash Flood Warning Considerable damage threat	SLC	Kane, Washington	3 hr
Jun 29, 2:14 PM MDT	Flash Flood Warning Considerable damage threat	SLC	Washington	3 hr
Jun 29, 3:09 PM MDT	Special Weather Statement	SLC		36 min
Jun 29, 4:03 PM MDT	Severe Thunderstorm Warning	SLC	Kane, San Juan	27 min
Jun 29, 4:40 PM MDT	Flash Flood Warning Considerable damage threat	SLC	Kane	3 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.