Alert archive / Utah / Flash Flood Warnings in 2018

Flash Flood Warning 65, NWS Salt Lake City, UT

August 22, 2018Duchesne County, Wasatch County, Utah

NWS Salt Lake City, UT issued this flash flood warning at Aug 22, 2018, 8:11 PM MDT for Duchesne County, Wasatch County, Utah. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Aug 22, 2018, 8:11 PM MDT (02:11 UTC)
Expired: Aug 22, 2018, 11:15 PM MDT
In force: 3 hr
Issued by: NWS Salt Lake City, UT
Area: Storm-based polygon
Flood severity: None

Counties Duchesne County, UT, Wasatch County, UT

The radar

The Salt Lake City radar (KMTX), 182 km from the middle of the area, began a volume at 02:12 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.

The nearest sounding before it

Salt Lake City I, UT (KSLC), launched 00:00Z, 2.2 hours before the alert went out and 112 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: 21 J/kg
Mixed-layer CIN: -276 J/kg
Mixed-layer LCL: 2003 m above ground
0-6 km bulk shear: 48 kt
0-1 km storm-relative helicity: 19 m²/s²
0-3 km storm-relative helicity: 131 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

386 
WGUS55 KSLC 230211
FFWSLC
UTC013-051-230515-
/O.NEW.KSLC.FF.W.0065.180823T0211Z-180823T0515Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Salt Lake City UT
811 PM MDT WED AUG 22 2018

The National Weather Service in Salt Lake City has issued a

* Flash Flood Warning for...
  Southeastern Wasatch County in northern Utah...
  West central Duchesne County in northern Utah...

* Until 1115 PM MDT
    
* At 808 PM MDT, Doppler radar indicated a thunderstorm producing 
  heavy rain over the Dollar Ridge Burn Scar.  This scar has already 
  produced a debris flow earlier today, and additional rainfall is 
  imminent.
  
* Radar rainfall estimates over the northern aspect of the scar 
  indicate that up to an inch has fallen.

* This debris flow is expected to impact SR40 to the west of 
  Fruitland, Utah.

* Flash flooding will remain over mainly rural areas of southeastern
  Wasatch and west central Duchesne Counties.

LAT...LON 4021 11087 4016 11068 4002 11084 4000 11106
      4021 11101

$$

McInerney

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 22, 6:00 PM MDT	Special Weather Statement	SLC	Summit	45 min
Aug 22, 6:02 PM MDT	Flash Flood Warning	SLC	Summit	3 hr
Aug 22, 6:27 PM MDT	Special Weather Statement	SLC	Salt Lake	33 min
Aug 22, 6:39 PM MDT	Severe Thunderstorm Warning	SLC	Utah	36 min
Aug 22, 6:41 PM MDT	Special Weather Statement	SLC	Salt Lake	34 min
Aug 22, 7:06 PM MDT	Special Weather Statement	SLC	Utah	24 min
Aug 22, 7:14 PM MDT	Special Weather Statement	SLC	Wasatch	31 min
Aug 22, 7:30 PM MDT	Special Weather Statement	SLC	Utah	30 min
Aug 22, 9:09 PM MDT	Flash Flood Warning	SLC	Utah, Wasatch	3 hr
Aug 22, 11:02 PM MDT	Flash Flood Warning	SLC	Duchesne, Wasatch	4 hr
Aug 22, 11:38 PM MDT	Special Weather Statement	SLC	Carbon	52 min
Aug 23, 12:00 AM MDT	Special Weather Statement	SLC	Sanpete	45 min
Aug 23, 12:08 AM MDT	Severe Thunderstorm Warning	SLC	Juab, Sanpete, Utah	45 min
Aug 23, 1:00 PM MDT	Special Weather Statement	SLC	Kane	30 min
Aug 23, 1:13 PM MDT	Flash Flood Warning	SLC	Garfield, Kane	3 hr

Nearby

Flash Flood Warnings in Utah, 2018 Every flash flood warning in 2018

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.