Alert archive / Utah / Flash Flood Warnings in 2021
Flash Flood Warning 73, NWS Salt Lake City, UT
NWS Salt Lake City, UT issued this flash flood warning at Jul 31, 2021, 4:10 PM MDT for Utah 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
- Jul 31, 2021, 4:10 PM MDT (22:10 UTC)
- Expired
- Jul 31, 2021, 7:00 PM MDT
- In force
- 3 hr
- Issued by
- NWS Salt Lake City, UT
- Area
- Storm-based polygon
- Damage threat
- Considerable
- Flood severity
- None
County Utah County, UT
The radar
The Salt Lake City radar (KMTX), 156 km from the middle of the area, began a volume at 22:13 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 12:00Z, 10.2 hours before the alert went out and 90 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
- 149 J/kg
- Mixed-layer CIN
- -128 J/kg
- Mixed-layer LCL
- 1716 m above ground
- 0-6 km bulk shear
- 5 kt
- 0-1 km storm-relative helicity
- 44 m²/s²
- 0-3 km storm-relative helicity
- 76 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
439
WGUS55 KSLC 312210
FFWSLC
UTC049-010100-
/O.NEW.KSLC.FF.W.0073.210731T2210Z-210801T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Salt Lake City UT
410 PM MDT Sat Jul 31 2021
The National Weather Service in Salt Lake City has issued a
* Flash Flood Warning for...
The Bald Mountain Burn Scar in...
Southern Utah County in northern Utah...
* Until 700 PM MDT.
* At 410 PM MDT, Doppler radar indicated thunderstorms producing
heavy rain over the Bald Mountain Burn Scar, specifically above
the Loafer Canyon area. Between 0.25 and 0.6 inches of rain have
fallen. Additional rainfall amounts of 0.25 to 0.5 inches are
possible over the next 30 minutes in the warned area. Flash
flooding is ongoing or expected to begin shortly.
Excessive rainfall over the burn scar will result in debris flow
moving through the Loafer Canyon. The debris flow can consist of
rock, mud, vegetation and other loose materials.
HAZARD...Life threatening flash flooding. Thunderstorms
producing flash flooding in and around the Bald
Mountain Burn Scar, specifically Loafer Canyon.
SOURCE...Radar.
IMPACT...Life threatening flash flooding of areas in and around
the Bald Mountain Burn Scar.
* Some locations that will experience flash flooding include...
Elk Ridge and Woodland Hills.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Be aware of your surroundings and do not drive on flooded roads.
&&
LAT...LON 4002 11168 4002 11167 4001 11165 3998 11159
3995 11165 3997 11168
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
GM1 follow-up statement
126
WGUS75 KSLC 010057
FFSSLC
Flash Flood Statement
National Weather Service Salt Lake City UT
657 PM MDT Sat Jul 31 2021
UTC049-010107-
/O.EXP.KSLC.FF.W.0073.000000T0000Z-210801T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Utah UT-
657 PM MDT Sat Jul 31 2021
...FLASH FLOOD WARNING FOR THE BALD MOUNTAIN BURN SCAR WILL EXPIRE
AT 7 PM MDT THIS EVENING FOR SOUTHERN UTAH COUNTY...
Flooding is no longer expected to pose a threat. Please continue to
heed any information from officials on site.
LAT...LON 4002 11168 4002 11167 4001 11165 3998 11159
3995 11165 3997 11168
$$
GMThe office that day
Everything else NWS Salt Lake City, UT issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 30, 7:17 PM MDT | Special Weather Statement | SLC | Beaver | 43 min |
| Jul 30, 7:31 PM MDT | Special Weather Statement | SLC | 44 min | |
| Jul 31, 12:31 PM MDT | Special Weather Statement | SLC | Summit | 44 min |
| Jul 31, 1:12 PM MDT | Special Weather Statement | SLC | Iron | 33 min |
| Jul 31, 1:23 PM MDT | Flash Flood Warning | SLC | Duchesne, Wasatch | 3 hr |
| Jul 31, 1:30 PM MDT | Severe Thunderstorm Warning | SLC | Iron, Washington | 30 min |
| Jul 31, 1:39 PM MDT | Special Weather Statement | SLC | Morgan | 36 min |
| Jul 31, 2:10 PM MDT | Special Weather Statement | SLC | Morgan | 50 min |
| Jul 31, 2:38 PM MDT | Special Weather Statement | SLC | Morgan | 37 min |
| Jul 31, 2:47 PM MDT | Severe Thunderstorm Warning | SLC | Morgan, Rich, Summit | 28 min |
| Jul 31, 2:52 PM MDT | Special Weather Statement | SLC | Rich | 23 min |
| Jul 31, 3:00 PM MDT | Areal Flood Advisory | SLC | Iron | 107 min |
| Jul 31, 3:10 PM MDT | Special Weather Statement | SLC | Morgan | 20 min |
| Jul 31, 3:16 PM MDT | Severe Thunderstorm Warning | SLC | Box Elder, Cache, Weber | 29 min |
| Jul 31, 3:35 PM MDT | Flash Flood Warning | SLC | Iron | 3 hr |
| Jul 31, 3:41 PM MDT | Special Weather Statement | SLC | Cache | 19 min |
| Jul 31, 4:00 PM MDT | Severe Thunderstorm Warning | SLC | Iron | 30 min |
| Jul 31, 4:06 PM MDT | Special Weather Statement | SLC | Beaver | 24 min |
| Jul 31, 4:19 PM MDT | Flash Flood Warning | SLC | Duchesne | 3 hr |
| Jul 31, 4:39 PM MDT | Special Weather Statement | SLC | Rich | 66 min |
| Jul 31, 5:01 PM MDT | Special Weather Statement | SLC | 29 min | |
| Jul 31, 5:11 PM MDT | Flash Flood Warning | SLC | Washington | 3 hr |
| Jul 31, 5:25 PM MDT | Special Weather Statement | SLC | Juab | 35 min |
| Jul 31, 5:37 PM MDT | Special Weather Statement | SLC | Washington | 38 min |
| Jul 31, 5:39 PM MDT | Flash Flood Warning | SLC | Kane, Washington | 5 hr |
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.