Alert archive / Utah / Flash Flood Watches in 2021

Flash Flood Watch 3, NWS Salt Lake City, UT

July 15, 202110 counties in Utah

NWS Salt Lake City, UT issued this flash flood watch at Jul 15, 2021, 2:53 AM MDT for 10 counties in Utah. It took effect at Jul 15, 2021, 12:00 PM MDT. It was in force for 16 hr.

The area

The counties it named.

The facts

Issued
Jul 15, 2021, 2:53 AM MDT (08:53 UTC)
In effect from
Jul 15, 2021, 12:00 PM MDT
Expired
Jul 16, 2021, 4:07 AM MDT
In force
16 hr
Issued by
NWS Salt Lake City, UT
Flood severity
None

Counties Beaver County, UT, Emery County, UT, Garfield County, UT, Iron County, UT, Kane County, UT, Piute County, UT, San Juan County, UT, Sevier County, UT, Washington County, UT, Wayne County, UT

The radar

The Cedar City radar (KICX), 102 km from the middle of the area, began a volume at 08:56 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 00:00Z, 8.9 hours before the alert went out and 302 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, Salt Lake City I, UT at 00:00Z on 2021-07-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 592 joules per kilogram.LCLEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Salt Lake City I, UT at 00:00Z on 2021-07-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 32 square meters per square second.193958Sfc1 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
592 J/kg
Mixed-layer CIN
-5 J/kg
Mixed-layer LCL
3202 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
32 m²/s²
0-3 km storm-relative helicity
51 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.6

Open this sounding in Storm Lab

The text

As transmitted.

558 
WGUS65 KSLC 150853
FFASLC

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Salt Lake City UT
253 AM MDT Thu Jul 15 2021

UTZ122>131-151700-
/O.NEW.KSLC.FF.A.0003.210715T1800Z-210716T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Southwest Utah-Lower Washington County-Zion National Park-Southern
Mountains-Upper Sevier River Valleys-Bryce Canyon Country-South
Central Utah-Capitol Reef National Park and Vicinity-Western
Canyonlands-Glen Canyon Recreation Area/Lake Powell-
Including the cities of Bullfrog, Milford, Circleville, Kanab, 
Alton, St George, Torrey, Hurricane, Koosharem, Bryce Canyon City, 
Cedar City, Panguitch, Loa, Escalante, Springdale, Brian Head, 
Beaver, Ivins, Big Water, and Hanksville
253 AM MDT Thu Jul 15 2021

...FLASH FLOOD WATCH IN EFFECT FROM NOON MDT TODAY THROUGH LATE THIS 
EVENING...

The National Weather Service in Salt Lake City has issued a

* Flash Flood Watch for a portion of Utah, including the following 
  areas, Bryce Canyon Country, Capitol Reef National Park and 
  Vicinity, Glen Canyon Recreation Area/Lake Powell, South Central 
  Utah, Southern Mountains, Upper Sevier River Valleys, Western 
  Canyonlands, Lower Washington County, Southwest Utah and Zion 
  National Park.

* From Noon MDT today through this evening.

* Showers and thunderstorms will develop across the watch area this 
  afternoon and evening.  Heavy rainfall will be possible with any 
  showers or thunderstorms.

* Flash flooding is possible, especially in slot canyons, normally 
  dry washes, areas in or near slickrock, and in vicinity of recent 
  burn scars. Those venturing in the backcountry could encounter 
  flooded, washed out or impassible roadways.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

CRK
6 follow-up statements
046 
WGUS65 KSLC 151058
FFASLC

Flood Watch
National Weather Service Salt Lake City UT
458 AM MDT Thu Jul 15 2021

UTZ122>131-160600-
/O.CON.KSLC.FF.A.0003.210715T1800Z-210716T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Southwest Utah-Lower Washington County-Zion National Park-Southern
Mountains-Upper Sevier River Valleys-Bryce Canyon Country-South
Central Utah-Capitol Reef National Park and Vicinity-Western
Canyonlands-Glen Canyon Recreation Area/Lake Powell-
Including the cities of Bullfrog, Milford, Circleville, Kanab, 
Alton, St George, Torrey, Hurricane, Koosharem, Bryce Canyon City, 
Cedar City, Panguitch, Loa, Escalante, Springdale, Brian Head, 
Beaver, Ivins, Big Water, and Hanksville
458 AM MDT Thu Jul 15 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT FROM NOON MDT TODAY THROUGH 
LATE THIS EVENING...

The Flash Flood Watch continues for

* A portion of Utah, including the following areas, Bryce Canyon 
  Country, Capitol Reef National Park and Vicinity, Glen Canyon 
  Recreation Area/Lake Powell, South Central Utah, Southern 
  Mountains, Upper Sevier River Valleys, Western Canyonlands, Lower 
  Washington County, Southwest Utah and Zion National Park.

* From Noon MDT today through this evening.

* Showers and thunderstorms will develop across the watch area this 
  afternoon and evening.  Heavy rainfall will be possible with any 
  showers or thunderstorms.

* Flash flooding is possible, especially in slot canyons, normally 
  dry washes, areas in or near slickrock, and in vicinity of recent 
  burn scars. Those venturing in the backcountry could encounter 
  flooded, washed out or impassible roadways.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

CRK
243 
WGUS65 KSLC 152130
FFASLC

Flood Watch
National Weather Service Salt Lake City UT
330 PM MDT Thu Jul 15 2021

UTZ122>131-160600-
/O.CON.KSLC.FF.A.0003.000000T0000Z-210716T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Southwest Utah-Lower Washington County-Zion National Park-Southern
Mountains-Upper Sevier River Valleys-Bryce Canyon Country-South
Central Utah-Capitol Reef National Park and Vicinity-Western
Canyonlands-Glen Canyon Recreation Area/Lake Powell-
Including the cities of Bullfrog, Milford, Circleville, Kanab, 
Alton, St George, Torrey, Hurricane, Koosharem, Bryce Canyon City, 
Cedar City, Panguitch, Loa, Escalante, Springdale, Brian Head, 
Beaver, Ivins, Big Water, and Hanksville
330 PM MDT Thu Jul 15 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT UNTIL MIDNIGHT MDT TONIGHT...

The Flash Flood Watch continues for

* A portion of Utah, including the following areas, Bryce Canyon 
  Country, Capitol Reef National Park and Vicinity, Glen Canyon 
  Recreation Area/Lake Powell, South Central Utah, Southern 
  Mountains, Upper Sevier River Valleys, Western Canyonlands, Lower 
  Washington County, Southwest Utah and Zion National Park.

* Until Midnight MDT tonight.

* Scattered showers and thunderstorms capable of producing heavy 
  rainfall will remain possible through the evening hours.

* Flash flooding is possible, especially in slot canyons, normally 
  dry washes, areas in or near slickrock, and in vicinity of recent 
  burn scars. Those venturing in the backcountry could encounter 
  flooded, washed out or impassible roadways.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

MPS
660 
WGUS65 KSLC 160119
FFASLC

Flood Watch
National Weather Service Salt Lake City UT
719 PM MDT Thu Jul 15 2021

UTZ129>131-160230-
/O.CAN.KSLC.FF.A.0003.000000T0000Z-210716T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Capitol Reef National Park and Vicinity-Western Canyonlands-Glen
Canyon Recreation Area/Lake Powell-
Including the cities of Torrey, Bullfrog, Loa, Big Water, and 
Hanksville
719 PM MDT Thu Jul 15 2021

...FLASH FLOOD WATCH IS CANCELLED...

The Flash Flood Watch has been cancelled for a portion of Utah, 
including the following areas, Capitol Reef National Park and 
Vicinity, Glen Canyon Recreation Area/Lake Powell and Western 
Canyonlands.

The threat for heavy rain has ended across the area. Therefore the 
Flash Flood Watch has been cancelled.

$$

UTZ122>128-160600-
/O.CON.KSLC.FF.A.0003.000000T0000Z-210716T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Southwest Utah-Lower Washington County-Zion National Park-Southern
Mountains-Upper Sevier River Valleys-Bryce Canyon Country-South
Central Utah-
Including the cities of Milford, Circleville, Kanab, Alton, St 
George, Hurricane, Koosharem, Bryce Canyon City, Cedar City, 
Panguitch, Escalante, Springdale, Brian Head, Beaver, and Ivins
719 PM MDT Thu Jul 15 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT UNTIL MIDNIGHT MDT TONIGHT...

The Flash Flood Watch continues for

* A portion of Utah, including the following areas, Bryce Canyon 
  Country, South Central Utah, Southern Mountains, Upper Sevier 
  River Valleys, Lower Washington County, Southwest Utah and Zion 
  National Park.

* Until Midnight MDT tonight.

* Scattered showers and thunderstorms capable of producing heavy 
  rainfall will remain possible through the evening hours.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

MPS
132 
WGUS65 KSLC 160549
FFASLC

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Salt Lake City UT
1149 PM MDT Thu Jul 15 2021

UTZ122-125>128-160700-
/O.EXP.KSLC.FF.A.0003.000000T0000Z-210716T0600Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Southwest Utah-Southern Mountains-Upper Sevier River Valleys-Bryce
Canyon Country-South Central Utah-
Including the cities of Milford, Circleville, Kanab, Alton, 
Koosharem, Bryce Canyon City, Cedar City, Panguitch, Escalante, 
Brian Head, and Beaver
1149 PM MDT Thu Jul 15 2021

...FLASH FLOOD WATCH WILL EXPIRE AT MIDNIGHT MDT TONIGHT...

The Flash Flood Watch will expire at Midnight MDT tonight for a 
portion of Utah, including the following areas, Bryce Canyon 
Country, South Central Utah, Southern Mountains, Upper Sevier River 
Valleys and Southwest Utah.

The Flood Watch is cancelled. Flooding is no longer expected to pose 
a threat. Please continue to heed remaining road closures.

$$

UTZ123-124-160900-
/O.EXT.KSLC.FF.A.0003.000000T0000Z-210716T0900Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Lower Washington County-Zion National Park-
Including the cities of St George, Ivins, Hurricane, and Springdale
1149 PM MDT Thu Jul 15 2021

...FLASH FLOOD WATCH NOW IN EFFECT UNTIL 3 AM MDT FRIDAY...

The Flash Flood Watch is now in effect for

* A portion of Utah, including the following areas, Lower Washington 
  County and Zion National Park.

* Until 3 AM MDT Friday.

* Scattered showers and thunderstorms capable of producing heavy 
  rainfall will remain possible through the early morning hours.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

Church
819 
WGUS65 KSLC 160850
FFASLC

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Salt Lake City UT
250 AM MDT Fri Jul 16 2021

UTZ123-124-161200-
/O.EXT.KSLC.FF.A.0003.000000T0000Z-210716T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Lower Washington County-Zion National Park-
Including the cities of St George, Ivins, Hurricane, and Springdale
250 AM MDT Fri Jul 16 2021

...FLASH FLOOD WATCH NOW IN EFFECT UNTIL 6 AM MDT EARLY THIS 
MORNING...

The Flash Flood Watch is now in effect for

* A portion of Utah, including the following areas, Lower Washington 
  County and Zion National Park.

* Until 6 AM MDT early this morning.

* Scattered showers and thunderstorms capable of producing heavy 
  rainfall will remain possible through the early morning hours.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

CRK
608 
WGUS65 KSLC 161007
FFASLC

Flood Watch
National Weather Service Salt Lake City UT
407 AM MDT Fri Jul 16 2021

UTZ123-124-161115-
/O.CAN.KSLC.FF.A.0003.000000T0000Z-210716T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Lower Washington County-Zion National Park-
Including the cities of St George, Ivins, Hurricane, and Springdale
407 AM MDT Fri Jul 16 2021

...FLASH FLOOD WATCH IS CANCELLED...

The Flash Flood Watch has been cancelled for a portion of Utah, 
including the following areas, Lower Washington County and Zion 
National Park.

The heavy rain has ended. Elevated flows will continue across slot 
canyons, normally dry washes and streams in the area through at 
least mid-morning.

$$

CRK

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 14, 6:20 PM MDTSpecial Weather StatementSLCEmery40 min
Jul 14, 6:25 PM MDTSevere Thunderstorm WarningSLCIron, Washington50 min
Jul 14, 6:49 PM MDTSpecial Weather StatementSLCIron41 min
Jul 14, 7:07 PM MDTFlash Flood Warning Considerable damage threatSLCKane, Washington3 hr
Jul 14, 7:53 PM MDTSevere Thunderstorm WarningSLCWashington69 min
Jul 15, 4:43 PM MDTSpecial Weather StatementSLCCarbon47 min
Jul 15, 5:01 PM MDTSpecial Weather StatementSLCGarfield44 min
Jul 15, 5:03 PM MDTSpecial Weather StatementSLCTooele57 min
Jul 15, 5:29 PM MDTSpecial Weather StatementSLCWeber61 min

Nearby

Flash Flood Watches in Utah, 2021Every flash flood watch 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.