Alert archive / Utah / Flash Flood Warnings in 2011

Flash Flood Warning 7, NWS Salt Lake City, UT

July 11, 2011Wayne County, Utah

NWS Salt Lake City, UT issued this flash flood warning at Jul 11, 2011, 1:35 PM MDT for Wayne County, Utah. It was in force for 4 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 11, 2011, 1:35 PM MDT (19:35 UTC)
Expired
Jul 11, 2011, 5:30 PM MDT
In force
4 hr
Issued by
NWS Salt Lake City, UT
Area
Storm-based polygon
Flood severity
None

County Wayne County, UT

The radar

The Cedar City radar (KICX), 160 km from the middle of the area, began a volume at 19:35 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.

The nearest sounding before it

Grand Junction, CO (KGJT), launched 12:00Z, 7.6 hours before the alert went out and 257 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 2011-07-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 171 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 2011-07-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 81 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
171 J/kg
Mixed-layer CIN
-134 J/kg
Mixed-layer LCL
1172 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
81 m²/s²
0-3 km storm-relative helicity
101 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.4

Open this sounding in Storm Lab

The text

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

635 
WGUS55 KSLC 111935
FFWSLC
UTC055-112330-
/O.NEW.KSLC.FF.W.0007.110711T1935Z-110711T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
135 PM MDT MON JUL 11 2011

THE NATIONAL WEATHER SERVICE IN SALT LAKE CITY HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTH CENTRAL WAYNE COUNTY IN UTAH...
  THIS INCLUDES CAPITOL REEF NATIONAL PARK...

* UNTIL 530 PM MDT

* AT 128 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  HEAVY RAIN FROM A THUNDERSTORM OVER THE PARK. LOCATIONS IMPACTED 
  INCLUDE THE FREMONT TRAIL...GRAND WASH TRAIL...AND SCENIC DRIVE. 

* RADAR ESTIMATES 0.75 TO 1 INCH OF RAIN HAS FALLEN ACROSS DRAINAGES 
  LEADING INTO THE PARK OVER THE PAST HOUR. THUNDERSTORMS WILL 
  CONTINUE TO BRING HEAVY RAIN TO THE AREA THROUGH AT LEAST 2 PM. 
  RUNOFF FROM THIS RAINFALL WILL RESULT IN 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 3827 11130 3827 11114 3816 11114 3816 11122

$$

SEAMAN
2 follow-up statements
522 
WGUS75 KSLC 112005
FFSSLC

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
205 PM MDT MON JUL 11 2011

UTC055-112330-
/O.CON.KSLC.FF.W.0007.000000T0000Z-110711T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
WAYNE UT-
205 PM MDT MON JUL 11 2011

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 530 PM MDT FOR SOUTH
CENTRAL WAYNE COUNTY...

AT 200 PM MDT...FLASH FLOODING HAS BEEN REPORTED ALONG SULPHUR CREEK 
WITHIN CAPITOL REEF NATIONAL PARK...AND THE SCENIC DRIVE HAS BEEN 
CLOSED. WATER HAS ALSO BEEN REPORTED FLOWING ACROSS SCENIC DRIVE 
BETWEEN THE VISITOR CENTER AND SLICKROCK DIVIDE. 

NATIONAL WEATHER SERVICE DOPPLER RADAR ESTIMATES ONE HALF TO ONCE 
INCH OF RAIN HAS FALLEN ACROSS THE AREA. ALTHOUGH THE THUNDERSTORM 
WHICH PRODUCED THIS HEAVY RAINFALL HAS WEAKENED AND MOVED NORTH OF 
THE AREA...EXCESSIVE RUNOFF AND FLASH FLOODING WILL LIKELY PERSIST 
THROUGH 5 PM. 

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 3827 11130 3827 11114 3816 11114 3816 11122

$$

SEAMAN
337 
WGUS75 KSLC 112333
FFSSLC

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
533 PM MDT MON JUL 11 2011

UTC055-112343-
/O.EXP.KSLC.FF.W.0007.000000T0000Z-110711T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
WAYNE UT-
533 PM MDT MON JUL 11 2011

...THE FLASH FLOOD WARNING HAS EXPIRED FOR CAPITOL REEF NATIONAL 
PARK IN SOUTH CENTRAL WAYNE COUNTY...

RUNOFF FROM EARLIER PRECIPITATION HAS DIMINISHED GREATLY AND RIVER 
AND STREAM LEVELS HAVE DECREASED. THEREFORE...THE FLASH FLOOD 
WARNING HAS BEEN ALLOWED TO EXPIRE. MONITOR NOAA WEATHER RADIO OR 
LOCAL TELEVISION OR RADIO FOR THE LATEST WEATHER INFORMATION.

LAT...LON 3827 11130 3827 11114 3816 11114 3816 11122

$$

SEAMAN

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 11, 4:26 PM MDTSpecial Weather StatementSLC49 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.