Alert archive / Utah / Flash Flood Warnings in 2021

Flash Flood Warning 16, NWS Salt Lake City, UT

July 16, 2021Garfield County, Kane County, Utah

NWS Salt Lake City, UT issued this flash flood warning at Jul 16, 2021, 1:58 PM MDT for Garfield County, Kane 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 16, 2021, 1:58 PM MDT (19:58 UTC)
Expired: Jul 16, 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

Counties Garfield County, UT, Kane County, UT

The radar

The Cedar City radar (KICX), 33 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.

The nearest sounding before it

Flgstf/Belemont, AZ (KFGZ), launched 12:00Z, 8.0 hours before the alert went out and 262 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: 487 J/kg
Mixed-layer CIN: -59 J/kg
Mixed-layer LCL: 1090 m above ground
0-6 km bulk shear: 12 kt
0-1 km storm-relative helicity: 77 m²/s²
0-3 km storm-relative helicity: 88 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

333 
WGUS55 KSLC 161958
FFWSLC
UTC017-025-162300-
/O.NEW.KSLC.FF.W.0016.210716T1958Z-210716T2300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Salt Lake City UT
158 PM MDT Fri Jul 16 2021

The National Weather Service in Salt Lake City has issued a

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

* Until 500 PM MDT.

* At 158 PM MDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 2 and 3 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...
  US-89 between Long Valley Junction and Hatch

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3755 11250 3757 11249 3756 11247 3753 11245
      3750 11246 3749 11247 3749 11249 3749 11250
      3749 11252 3750 11253 3751 11254 3753 11254

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

$$

SW

2 follow-up statements

766 
WGUS75 KSLC 162134
FFSSLC

Flash Flood Statement
National Weather Service Salt Lake City UT
334 PM MDT Fri Jul 16 2021

UTC017-025-162300-
/O.CON.KSLC.FF.W.0016.000000T0000Z-210716T2300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Garfield UT-Kane UT-
334 PM MDT Fri Jul 16 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 5 PM MDT THIS 
AFTERNOON FOR SOUTHWESTERN GARFIELD AND NORTHWESTERN KANE COUNTIES...

At 334 PM MDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 3 and 4 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...
  US-89 between Long Valley Junction and Hatch.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3755 11250 3757 11249 3756 11247 3753 11245
      3750 11246 3749 11247 3749 11249 3749 11250
      3749 11252 3750 11253 3751 11254 3753 11254

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

$$

SW

747 
WGUS75 KSLC 162300
FFSSLC

Flash Flood Statement
National Weather Service Salt Lake City UT
500 PM MDT Fri Jul 16 2021

UTC017-025-162310-
/O.EXP.KSLC.FF.W.0016.000000T0000Z-210716T2300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Garfield UT-Kane UT-
500 PM MDT Fri Jul 16 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 5 PM MDT THIS AFTERNOON FOR 
SOUTHWESTERN GARFIELD AND NORTHWESTERN KANE COUNTIES...

The heavy rain has ended. Flooding is no longer expected to pose a 
threat. Please continue to heed remaining road closures.

LAT...LON 3755 11250 3757 11249 3756 11247 3753 11245
      3750 11246 3749 11247 3749 11249 3749 11250
      3749 11252 3750 11253 3751 11254 3753 11254

$$

SW

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 15, 6:35 PM MDT	Special Weather Statement	SLC	Salt Lake	40 min
Jul 15, 7:08 PM MDT	Severe Thunderstorm Warning	SLC	Iron	52 min
Jul 15, 8:39 PM MDT	Flash Flood Warning Considerable damage threat	SLC	Beaver, Iron	3 hr
Jul 16, 12:39 AM MDT	Flash Flood Warning Considerable damage threat	SLC	Kane, Washington	3 hr
Jul 16, 1:05 AM MDT	Flash Flood Warning Considerable damage threat	SLC	Kane, Washington	3 hr
Jul 16, 1:09 AM MDT	Areal Flood Advisory	SLC	Washington	3 hr
Jul 16, 1:07 PM MDT	Special Weather Statement	SLC	Kane	38 min
Jul 16, 1:27 PM MDT	Flash Flood Warning Considerable damage threat	SLC	Kane	3 hr
Jul 16, 3:20 PM MDT	Special Weather Statement	SLC		40 min
Jul 16, 3:47 PM MDT	Flash Flood Warning Considerable damage threat	SLC	Garfield, Kane	3 hr
Jul 16, 4:46 PM MDT	Special Weather Statement	SLC	Millard	44 min
Jul 16, 5:04 PM MDT	Severe Thunderstorm Warning	SLC	Millard	56 min

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.