Alert archive / Utah / Flash Flood Warnings in 2011

Flash Flood Warning 21, 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, 3:07 PM MDT for Garfield County, Wayne 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
Aug 1, 2011, 3:07 PM MDT (21:07 UTC)
Expired
Aug 1, 2011, 6:00 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), 158 km from the middle of the area, began a volume at 21:09 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

Grand Junction, CO (KGJT), launched 12:00Z, 9.1 hours before the alert went out and 259 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, Grand Junction, CO at 12:00Z on 2011-08-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 8 joules per kilogram.LCLLFCEL10008507005003002001001 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, Grand Junction, CO at 12:00Z on 2011-08-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 82 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
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.

578 
WGUS55 KSLC 012107
FFWSLC
UTC017-055-020000-
/O.NEW.KSLC.FF.W.0021.110801T2107Z-110802T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
307 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...
  SOUTH CENTRAL WAYNE COUNTY IN UTAH...

* UNTIL 600 PM MDT

* AT 300 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  FLASH FLOODING FROM A THUNDERSTORM OVER PLEASANT CREEK AND BURRO   
  WASH IN CAPITOL REEF NATIONAL PARK.

* CAPITOL REEF NATIONAL PARK IS A VERY FLASH FLOOD PRONE AREA...AND  
  ANYONE VENTURING INTO THESE DRAINAGES NEEDS TO BE AWARE OF FLASH   
  FLOODING.

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 3812 11139 3820 11132 3826 11113 3829 11104
      3819 11103 3807 11107 3802 11109 3801 11120
      3803 11134

$$

MCINERNEY
1 follow-up statement
829 
WGUS75 KSLC 012355
FFSSLC

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

UTC017-055-020004-
/O.EXP.KSLC.FF.W.0021.000000T0000Z-110802T0000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
GARFIELD UT-WAYNE UT-
555 PM MDT MON AUG 1 2011

...THE FLASH FLOOD WARNING WILL EXPIRE AT 600 PM MDT FOR THE BURRO 
AND PLEASANT CREEK DRAINAGES IN CAPITOL REEF NATIONAL PARK...

THUNDERSTORM ACTIVITY IN THE AREA HAS MOVED TO THE EAST...AND FLOOD 
WATERS HAVE ATTENUATED.  AS A RESULT...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 3812 11139 3820 11132 3826 11113 3829 11104
      3819 11103 3807 11107 3802 11109 3801 11120
      3803 11134

$$

MCINERNEY

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 31, 6:21 PM MDTFlash Flood WarningSLCKane3 hr
Aug 1, 6:59 AM MDTAreal Flood AdvisorySLCBox Elder, Cache, Davis, Weber2 hr
Aug 1, 3:35 PM MDTFlash Flood WarningSLCGarfield, Wayne3 hr
Aug 1, 5:39 PM MDTSevere Thunderstorm WarningSLCBox Elder36 min

Nearby

Flash Flood Warnings in Utah, 2011Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.