Alert archive / Utah / Flash Flood Warnings in 2021
Flash Flood Warning 96, NWS Salt Lake City, UT
NWS Salt Lake City, UT issued this flash flood warning at Aug 17, 2021, 4:53 PM MDT for Garfield 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 17, 2021, 4:53 PM MDT (22:53 UTC)
- Expired
- Aug 17, 2021, 8:00 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), 140 km from the middle of the area, began a volume at 22:52 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
Flgstf/Belemont, AZ (KFGZ), launched 12:00Z, 10.9 hours before the alert went out and 273 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.
- Mixed-layer CAPE
- 984 J/kg
- Mixed-layer CIN
- -55 J/kg
- Mixed-layer LCL
- 829 m above ground
- 0-6 km bulk shear
- 19 kt
- 0-1 km storm-relative helicity
- 135 m²/s²
- 0-3 km storm-relative helicity
- 154 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 2.8
The text
As transmitted.
641
WGUS55 KSLC 172253
FFWSLC
UTC017-180200-
/O.NEW.KSLC.FF.W.0096.210817T2253Z-210818T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Salt Lake City UT
453 PM MDT Tue Aug 17 2021
The National Weather Service in Salt Lake City has issued a
* Flash Flood Warning for...
South Central Garfield County in southern Utah...
* Until 800 PM MDT.
* At 453 PM MDT, Doppler radar indicated thunderstorms producing
heavy rain across the warned area. Between 0.5 and 1.25 inches of
rain have fallen. 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 South Central Garfield County
This includes the following streams and drainages...
Harris Wash, Twentyfive Mile Wash, Red Breaks, Little Death
Hollow, Wolverine Canyon and the Escalante River.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
&&
LAT...LON 3769 11138 3781 11124 3779 11118 3766 11107
3758 11113 3755 11119 3755 11131 3757 11135
3762 11140 3765 11142
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
SW2 follow-up statements
989
WGUS75 KSLC 180039
FFSSLC
Flash Flood Statement
National Weather Service Salt Lake City UT
639 PM MDT Tue Aug 17 2021
UTC017-180200-
/O.CON.KSLC.FF.W.0096.000000T0000Z-210818T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Garfield UT-
639 PM MDT Tue Aug 17 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 8 PM MDT THIS EVENING
FOR SOUTH CENTRAL GARFIELD COUNTY...
At 639 PM MDT, Doppler radar indicated thunderstorms producing heavy
rain across the warned area. Between 0.5 and 1.5 inches of rain have
fallen. Flash flooding is ongoing or expected to begin shortly.
HAZARD...Life threatening flash flooding. Thunderstorms producing
flash flooding.
SOURCE...Radar.
IMPACT...Life threatening flash flooding of creeks and streams,
urban areas, highways, streets and underpasses.
Some locations that will experience flash flooding include...
mainly rural areas of South Central Garfield County
This includes the following streams and drainages...
Harris Wash, Twentyfive Mile Wash, Red Breaks, Little Death
Hollow, Wolverine Canyon and the Escalante River.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
&&
LAT...LON 3769 11138 3781 11124 3779 11118 3766 11107
3758 11113 3755 11119 3755 11131 3757 11135
3762 11140 3765 11142
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
SW916
WGUS75 KSLC 180157
FFSSLC
Flash Flood Statement
National Weather Service Salt Lake City UT
757 PM MDT Tue Aug 17 2021
UTC017-180207-
/O.EXP.KSLC.FF.W.0096.000000T0000Z-210818T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Garfield UT-
757 PM MDT Tue Aug 17 2021
...FLASH FLOOD WARNING WILL EXPIRE AT 8 PM MDT THIS EVENING FOR
SOUTH CENTRAL GARFIELD COUNTY...
The heavy rain has ended. Flooding is no longer expected to pose a
threat. Runoff from earlier heavy rainfall will continue to diminish
through the evening hours. Additional light to moderate rainfall
will continue over the area for up to an hour. Please continue to
heed any road closures.
A Flash Flood Watch remains in effect until 1200 AM MDT Thursday for
portions of central Utah, northern Utah and southern Utah.
LAT...LON 3769 11138 3781 11124 3779 11118 3766 11107
3758 11113 3755 11119 3755 11131 3757 11135
3762 11140 3765 11142
$$
SWThe office that day
Everything else NWS Salt Lake City, UT issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 17, 1:31 PM MDT | Special Weather Statement | SLC | Kane | 44 min |
| Aug 17, 1:50 PM MDT | Severe Thunderstorm Warning | SLC | Garfield, Kane | 20 min |
| Aug 17, 2:23 PM MDT | Severe Thunderstorm Warning | SLC | Beaver, Garfield, Piute | 52 min |
| Aug 17, 2:50 PM MDT | Flash Flood Warning | SLC | Garfield | 3 hr |
| Aug 17, 3:14 PM MDT | Special Weather Statement | SLC | Juab | 31 min |
| Aug 17, 3:20 PM MDT | Special Weather Statement | SLC | Tooele | 25 min |
| Aug 17, 3:29 PM MDT | Severe Thunderstorm Warning | SLC | Sevier | 46 min |
| Aug 17, 3:51 PM MDT | Severe Thunderstorm Warning | SLC | Tooele | 24 min |
| Aug 17, 4:12 PM MDT | Severe Thunderstorm Warning | SLC | Tooele | 48 min |
| Aug 17, 4:18 PM MDT | Flash Flood Warning | SLC | Emery, Wayne | 3 hr |
| Aug 17, 4:29 PM MDT | Severe Thunderstorm Warning | SLC | Tooele | 46 min |
| Aug 17, 4:39 PM MDT | Severe Thunderstorm Warning | SLC | Millard | 66 min |
| Aug 17, 4:56 PM MDT | Severe Thunderstorm Warning | SLC | Garfield | 24 min |
| Aug 17, 5:00 PM MDT | Severe Thunderstorm Warning | SLC | Davis, Salt Lake, Tooele | 30 min |
| Aug 17, 5:10 PM MDT | Flash Flood Warning | SLC | Kane | 4 hr |
| Aug 17, 5:12 PM MDT | Severe Thunderstorm Warning | SLC | Tooele | 63 min |
| Aug 17, 5:30 PM MDT | Severe Thunderstorm Warning | SLC | Davis, Salt Lake | 45 min |
| Aug 17, 5:37 PM MDT | Flash Flood Warning | SLC | Garfield, Kane | 6 hr |
| Aug 17, 5:40 PM MDT | Severe Thunderstorm Warning | SLC | Millard | 50 min |
| Aug 17, 5:48 PM MDT | Special Weather Statement | SLC | Sanpete | 27 min |
Nearby
Flash Flood Warnings in Utah, 2021Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.