Alert archive / Utah / Flash Flood Warnings in 2011

Flash Flood Warning 22, NWS Salt Lake City, UT

August 1, 2011Garfield County, Wayne County, Utah

NWS Salt Lake City, UT issued this flash flood warning at Aug 1, 2011, 3:35 PM MDT for Garfield County, Wayne County, Utah. It was in force for 3 hr. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Aug 1, 2011, 3:35 PM MDT (21:35 UTC)
Expired: Aug 1, 2011, 6:30 PM MDT
In force: 3 hr
Issued by: NWS Salt Lake City, UT
Area: Storm-based polygon
Flood severity: None

Counties Garfield County, UT, Wayne County, UT

The radar

The Cedar City radar (KICX), 183 km from the middle of the area, began a volume at 21:35 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.

What was reported inside it

Time	Report	Where	Remark
Aug 1, 5:02 PM MDT	FLASH FLOOD	15 S Hanksville, UT	FLASH FLOOD ALONG THE WEST SLOPE OF THE HENRY MOUNTAINS, SPECIFICALLY SANDY CREEK.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Grand Junction, CO (KGJT), launched 12:00Z, 9.6 hours before the alert went out and 235 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: 8 J/kg
Mixed-layer CIN: -145 J/kg
Mixed-layer LCL: 1422 m above ground
0-6 km bulk shear: 16 kt
0-1 km storm-relative helicity: 82 m²/s²
0-3 km storm-relative helicity: 101 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

800 
WGUS55 KSLC 012135
FFWSLC
UTC017-055-020030-
/O.NEW.KSLC.FF.W.0022.110801T2135Z-110802T0030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
335 PM MDT MON AUG 1 2011

THE NATIONAL WEATHER SERVICE IN SALT LAKE CITY HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTH CENTRAL GARFIELD COUNTY IN UTAH...
  CENTRAL WAYNE COUNTY IN UTAH...

* UNTIL 630 PM MDT

* AT 330 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
THUNDERSTORMS CAPABLE OF PRODUCING VERY HEAVY RAIN OVER THE AREA 
EAST OF CAPITOL REEF NATIONAL PARK. THIS AREA ENCOMPASSES THE HENRY 
MOUNTAINS WITH SR 95 TO THE EAST...AND SR 24 TO THE NORTH.

* RAINFALL AMOUNTS FROM THIS STORM ARE OVER AN INCH OF RAIN IN A     
  VERY SHORT PERIOD OF TIME.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY.

&&

LAT...LON 3818 11103 3829 11104 3833 11102 3836 11093
      3837 11073 3803 11062 3793 11077 3800 11110

$$

MCINERNEY

3 follow-up statements

786 
WGUS75 KSLC 012249
FFSSLC

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
449 PM MDT MON AUG 1 2011

UTC017-055-020030-
/O.CON.KSLC.FF.W.0022.000000T0000Z-110802T0030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
GARFIELD UT-WAYNE UT-
449 PM MDT MON AUG 1 2011

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 630 PM MDT FOR
CENTRAL WAYNE AND NORTH CENTRAL GARFIELD COUNTIES...

AT 442 PM MDT...THUNDERSTORM ACTIVITY OVER CAPITOL REEF NATIONAL 
PARK HAS MOVED TO THE EAST OF THE PARK. RADAR RAINFALL ESTIMATES OF 
0.75 TO 1.0 INCHES FELL IN THE BURRO AND PLEASANT CREEK WASHES IN 
THE PARK.  FLOOD WATERS CONTINUE TO FLOW THROUGH THE AREA...BUT IT 
IS ANTICIPATED THAT THE FLOODING WILL ATTENUATE BY 6PM.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY.

&&

LAT...LON 3818 11103 3829 11104 3833 11102 3836 11093
      3837 11073 3803 11062 3793 11077 3800 11110

$$

MCINERNEY

431 
WGUS75 KSLC 012254
FFSSLC

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
454 PM MDT MON AUG 1 2011

UTC017-055-020030-
/O.CON.KSLC.FF.W.0022.000000T0000Z-110802T0030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
GARFIELD UT-WAYNE UT-
454 PM MDT MON AUG 1 2011

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 630 PM MDT FOR
CENTRAL WAYNE AND NORTH CENTRAL GARFIELD COUNTIES...

AT 448 PM MDT...THUNDERSTORM ACTIVITY OVER THE HENRY MOUNTAINS 
LOCATED JUST EAST OF CAPITOL REEF NATIONAL PARK HAS DIMINISHED.   

HOWEVER...RADAR RAINFALL AMOUNTS OF 1.25 - 1.5 INCHES HAS FALLEN 
OVER THE AREA.  FLASH FLOODING IS ANTICIPATED TO FLOW NORTH TO SR24 
AND EAST TO SR95.  FLOODING IS ANTICIPATED TO OCCUR IN VERY REMOTE 
AREAS OF THE HENRY MOUNTAIN RANGE.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY.

&&

LAT...LON 3818 11103 3829 11104 3833 11102 3836 11093
      3837 11073 3803 11062 3793 11077 3800 11110

$$

MCINERNEY

503 
WGUS75 KSLC 020024
FFSSLC

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
624 PM MDT MON AUG 1 2011

UTC017-055-020033-
/O.EXP.KSLC.FF.W.0022.000000T0000Z-110802T0030Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
GARFIELD UT-WAYNE UT-
624 PM MDT MON AUG 1 2011

...THE FLASH FLOOD WARNING WILL EXPIRE AT 630 PM MDT FOR CENTRAL
WAYNE AND NORTH CENTRAL GARFIELD COUNTIES...

RAINFALL OVER THE HENRY MOUNTAINS HAS DIMINISHED AND FLOOD FLOWS ARE 
EXPECTED TO ATTENUATE...AS SUCH...THE FLASH FLOOD WARNING HAS BEEN 
ALLOWED TO EXPIRE.

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS
SAFELY.

LAT...LON 3818 11103 3829 11104 3833 11102 3836 11093
      3837 11073 3803 11062 3793 11077 3800 11110

$$

MCINERNEY

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 31, 6:21 PM MDT	Flash Flood Warning	SLC	Kane	3 hr
Aug 1, 6:59 AM MDT	Areal Flood Advisory	SLC	Box Elder, Cache, Davis, Weber	2 hr
Aug 1, 3:07 PM MDT	Flash Flood Warning	SLC	Garfield, Wayne	3 hr
Aug 1, 5:39 PM MDT	Severe Thunderstorm Warning	SLC	Box Elder	36 min

Nearby

Flash Flood Warnings in Utah, 2011 Every flash flood warning in 2011

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.