Alert archive / Utah / Flash Flood Warnings in 2021

Flash Flood Warning 22, NWS Salt Lake City, UT

July 19, 2021Kane County, Utah

NWS Salt Lake City, UT issued this flash flood warning at Jul 19, 2021, 8:19 PM MDT for Kane County, Utah. It was in force for 86 min. 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 19, 2021, 8:19 PM MDT (02:19 UTC)
Expired
Jul 19, 2021, 9:45 PM MDT
In force
86 min
Issued by
NWS Salt Lake City, UT
Area
Storm-based polygon
Damage threat
Considerable
Flood severity
None

County Kane County, UT

The radar

The Cedar City radar (KICX), 132 km from the middle of the area, began a volume at 02:20 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 00:00Z, 2.3 hours before the alert went out and 211 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-pSkew-T log-p diagram, Flgstf/Belemont, AZ at 00:00Z on 2021-07-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 220 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Flgstf/Belemont, AZ at 00:00Z on 2021-07-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 5 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
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
220 J/kg
Mixed-layer CIN
-81 J/kg
Mixed-layer LCL
1401 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
5 m²/s²
0-3 km storm-relative helicity
79 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

107 
WGUS55 KSLC 200219
FFWSLC
UTC025-200345-
/O.NEW.KSLC.FF.W.0022.210720T0219Z-210720T0345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Salt Lake City UT
819 PM MDT Mon Jul 19 2021

The National Weather Service in Salt Lake City has issued a

* Flash Flood Warning for...
  South Central Kane County in southern Utah...

* Until 945 PM MDT.

* At 819 PM MDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 0.75 and 1 inch of rain 
  has 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...
  southern portions of Warm Creek and associated tributaries.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3715 11154 3715 11150 3714 11147 3712 11145
      3705 11142 3705 11146 3707 11147 3710 11155
      3711 11156

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

$$

SW
2 follow-up statements
262 
WGUS75 KSLC 200309
FFSSLC

Flash Flood Statement
National Weather Service Salt Lake City UT
909 PM MDT Mon Jul 19 2021

UTC025-200345-
/O.CON.KSLC.FF.W.0022.000000T0000Z-210720T0345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Kane UT-
909 PM MDT Mon Jul 19 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 945 PM MDT THIS 
EVENING FOR SOUTH CENTRAL KANE COUNTY...

At 909 PM MDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 0.75 and 1.1 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...
  the southern portions of Warm Creek and associated tributaries.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 3715 11154 3715 11150 3714 11147 3712 11145
      3705 11142 3705 11146 3707 11147 3710 11155
      3711 11156

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

$$

SW
055 
WGUS75 KSLC 200337
FFSSLC

Flash Flood Statement
National Weather Service Salt Lake City UT
937 PM MDT Mon Jul 19 2021

UTC025-200347-
/O.EXP.KSLC.FF.W.0022.000000T0000Z-210720T0345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Kane UT-
937 PM MDT Mon Jul 19 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 945 PM MDT THIS EVENING FOR 
SOUTH CENTRAL KANE COUNTY...

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

LAT...LON 3715 11154 3715 11150 3714 11147 3712 11145
      3705 11142 3705 11146 3707 11147 3710 11155
      3711 11156

$$

SW

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 19, 6:01 PM MDTSpecial Weather StatementSLCTooele59 min
Jul 19, 6:10 PM MDTSpecial Weather StatementSLCJuab65 min
Jul 19, 6:13 PM MDTSpecial Weather StatementSLCWashington47 min
Jul 20, 12:11 PM MDTFlash Flood Warning Considerable damage threatSLCWayne3 hr
Jul 20, 1:18 PM MDTFlash Flood Warning Considerable damage threatSLCIron, Washington4 hr
Jul 20, 2:21 PM MDTSpecial Weather StatementSLCIron39 min
Jul 20, 3:26 PM MDTFlash Flood Warning Considerable damage threatSLCGarfield, Kane6 hr
Jul 20, 3:41 PM MDTFlash Flood Warning Considerable damage threatSLCGarfield, Kane3 hr
Jul 20, 4:03 PM MDTSpecial Weather StatementSLCSevier27 min
Jul 20, 4:58 PM MDTFlash Flood Warning Considerable damage threatSLCGarfield3 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.