Alert archive / Utah / Flash Flood Warnings in 2021

Flash Flood Warning 41, NWS Salt Lake City, UT

July 24, 2021Kane County, Washington County, Utah

NWS Salt Lake City, UT issued this flash flood warning at Jul 24, 2021, 4:07 PM MDT for Kane County, Washington 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 24, 2021, 4:07 PM MDT (22:07 UTC)
Expired: Jul 24, 2021, 7:15 PM MDT
In force: 3 hr
Issued by: NWS Salt Lake City, UT
Area: Storm-based polygon
Damage threat: Considerable
Flood severity: None

Counties Kane County, UT, Washington County, UT

The radar

The Cedar City radar (KICX), 35 km from the middle of the area, began a volume at 22:08 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, 10.1 hours before the alert went out and 251 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1053 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: 13 m²/s²
0-3 km storm-relative helicity: -9 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

985 
WGUS55 KSLC 242207
FFWSLC
UTC025-053-250115-
/O.NEW.KSLC.FF.W.0041.210724T2207Z-210725T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Salt Lake City UT
407 PM MDT Sat Jul 24 2021

The National Weather Service in Salt Lake City has issued a

* Flash Flood Warning for...
  Western Kane County in southern Utah...
  East Central Washington County in southwestern Utah...

* Until 715 PM MDT.

* At 407 PM MDT, Zion National Park Rangers reported flash flooding 
  across the warned area. Between 0.5 and 1 inch of rain has fallen.

  HAZARD...Life threatening flash flooding. Heavy rain producing
           flash flooding.

  SOURCE...Public reported.

  IMPACT...Life threatening flash flooding of creeks and streams,
           urban areas, highways, streets and underpasses.

* Some locations that will experience flash flooding include...
  Zion National Park, Springdale and Rockville.

This includes the following streams and drainages...
  Clear Creek, Right Fork North Creek, East Fork Virgin River, North 
  Fork Virgin River, Kolob Creek, Virgin River and Blue Creek.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3731 11293 3730 11294 3727 11294 3723 11295
      3716 11300 3716 11302 3718 11301 3724 11297
      3726 11298 3726 11301 3728 11301 3729 11299
      3733 11301 3735 11298 3737 11294 3737 11291
      3735 11285 3734 11284 3732 11287 3731 11289

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

$$

SW

2 follow-up statements

387 
WGUS75 KSLC 250033 RRA
FFSSLC

Flash Flood Statement
National Weather Service Salt Lake City UT
633 PM MDT Sat Jul 24 2021

UTC025-053-250115-
/O.CON.KSLC.FF.W.0041.000000T0000Z-210725T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Kane UT-Washington UT-
633 PM MDT Sat Jul 24 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 715 PM MDT THIS 
EVENING FOR WESTERN KANE AND EAST CENTRAL WASHINGTON COUNTIES...

At 633 PM MDT, Zion National Park Rangers reported flash flooding 
across the warned area. Between 0.5 and 1 inch of rain has fallen.

HAZARD...Life threatening flash flooding. Heavy rain producing
         flash flooding.

SOURCE...Public reported.

IMPACT...Life threatening flash flooding of creeks and streams,
         urban areas, highways, streets and underpasses.

Some locations that will experience flash flooding include...
  Zion National Park, Springdale and Rockville.

This includes the following streams and drainages...
  Clear Creek, Right Fork North Creek, East Fork Virgin River, North 
  Fork Virgin River, Kolob Creek, Virgin River and Blue Creek.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3731 11293 3730 11294 3727 11294 3723 11295
      3716 11300 3716 11302 3718 11301 3724 11297
      3726 11298 3726 11301 3728 11301 3729 11299
      3733 11301 3735 11298 3737 11294 3737 11291
      3735 11285 3734 11284 3732 11287 3731 11289

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

$$

SW

421 
WGUS75 KSLC 250113
FFSSLC

Flash Flood Statement
National Weather Service Salt Lake City UT
713 PM MDT Sat Jul 24 2021

UTC025-053-250123-
/O.EXP.KSLC.FF.W.0041.000000T0000Z-210725T0115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Kane UT-Washington UT-
713 PM MDT Sat Jul 24 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 715 PM MDT THIS EVENING FOR 
WESTERN KANE AND EAST CENTRAL WASHINGTON COUNTIES...

Flood waters have receded. The heavy rain has ended. Flooding is no 
longer expected to pose a threat. Please continue to heed any road 
closures. Runoff from earlier heavy rainfall will continue to 
diminish through the evening hours.

A Flash Flood Watch remains in effect until 1000 PM MDT Sunday for 
portions of southern Utah and southwest Utah.

LAT...LON 3731 11293 3730 11294 3727 11294 3723 11295
      3716 11300 3716 11302 3718 11301 3724 11297
      3726 11298 3726 11301 3728 11301 3729 11299
      3733 11301 3735 11298 3737 11294 3737 11291
      3735 11285 3734 11284 3732 11287 3731 11289

$$

SW

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 23, 6:14 PM MDT	Areal Flood Advisory	SLC	Washington	61 min
Jul 24, 3:23 AM MDT	Flash Flood Watch	SLC	Beaver, Garfield, Iron, Kane, Piute, Washington and 1 more	42 hr
Jul 24, 12:56 PM MDT	Flash Flood Warning Considerable damage threat	SLC	Kane	3 hr
Jul 24, 12:58 PM MDT	Special Weather Statement	SLC	Kane	32 min
Jul 24, 1:34 PM MDT	Flash Flood Warning Considerable damage threat	SLC	Garfield, Kane	4 hr
Jul 24, 2:13 PM MDT	Flash Flood Warning Considerable damage threat	SLC	Washington	3 hr
Jul 24, 2:24 PM MDT	Severe Thunderstorm Warning	SLC	Washington	21 min
Jul 24, 3:16 PM MDT	Severe Thunderstorm Warning	SLC	Washington	29 min
Jul 24, 3:40 PM MDT	Severe Thunderstorm Warning	SLC	Iron, Washington	35 min
Jul 24, 4:04 PM MDT	Severe Thunderstorm Warning	SLC	Washington	26 min
Jul 24, 4:12 PM MDT	Flash Flood Warning Considerable damage threat	SLC	Iron, Washington	3 hr
Jul 24, 4:30 PM MDT	Severe Thunderstorm Warning	SLC	Washington	30 min
Jul 24, 5:24 PM MDT	Flash Flood Warning Considerable damage threat	SLC	Washington	3 hr

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.