Alert archive / Utah / Flash Flood Warnings in 2021

Flash Flood Warning 138, NWS Salt Lake City, UT

October 6, 2021Carbon County, Utah

NWS Salt Lake City, UT issued this flash flood warning at Oct 6, 2021, 8:48 AM MDT for Carbon County, Utah. It was in force for 90 min. 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: Oct 6, 2021, 8:48 AM MDT (14:48 UTC)
Expired: Oct 6, 2021, 10:18 AM MDT
In force: 90 min
Issued by: NWS Salt Lake City, UT
Area: Storm-based polygon
Damage threat: Considerable
Flood severity: None

County Carbon County, UT

The radar

The Salt Lake City radar (KMTX), 212 km from the middle of the area, began a volume at 14:50 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
Oct 6, 8:59 AM MDT	FLASH FLOOD	5 Nnw Helper, UT	UDOT REPORTS US-6 STILL CLOSED BETWEEN SOLDIER SUMMIT AND US-191 JCT DUE TO FLASH FLOODING NEAR MP227.

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

The nearest sounding before it

Salt Lake City I, UT (KSLC), launched 12:00Z, 2.8 hours before the alert went out and 142 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: 60 J/kg
Mixed-layer CIN: -72 J/kg
Mixed-layer LCL: 1312 m above ground
0-6 km bulk shear: 10 kt
0-1 km storm-relative helicity: -20 m²/s²
0-3 km storm-relative helicity: 97 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

460 
WGUS55 KSLC 061448
FFWSLC
UTC007-061645-
/O.NEW.KSLC.FF.W.0138.211006T1448Z-211006T1645Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Salt Lake City UT
848 AM MDT Wed Oct 6 2021

The National Weather Service in Salt Lake City has issued a

* Flash Flood Warning for...
  The Bear burn scar in...
  Northwestern Carbon County in central Utah...

* Until 1045 AM MDT.

* At 848 AM MDT, UDOT reported heavy rain over the Bear Burn Scar 
  resulting in flooding over US-6. 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 already occurring.

Excessive rainfall over the burn scar will result in debris flow 
moving through the Bear. The debris flow can consist of rock, mud, 
vegetation and other loose materials.

  HAZARD...Life threatening flash flooding. Heavy rain producing
           flash flooding in and around the Bear Burn Scar.

  SOURCE...Utah Department of Transportation reported.

  IMPACT...Life threatening flash flooding of areas in and around
           the Bear Burn Scar.

* Some locations that will experience flash flooding include...
  Helper and Castle Gate.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3977 11097 3981 11093 3973 11086 3969 11087
      3970 11095

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

$$

Church

1 follow-up statement

417 
WGUS75 KSLC 061618
FFSSLC

Flash Flood Statement
National Weather Service Salt Lake City UT
1018 AM MDT Wed Oct 6 2021

UTC007-061628-
/O.CAN.KSLC.FF.W.0138.000000T0000Z-211006T1645Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Carbon UT-
1018 AM MDT Wed Oct 6 2021

...FLASH FLOOD WARNING FOR THE BEAR BURN SCAR IS CANCELLED FOR 
NORTHWESTERN CARBON COUNTY...

ent of Transportation reported that flood waters have receded and US-

LAT...LON 3977 11097 3981 11093 3973 11086 3969 11087
      3970 11095

$$

Church

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.