Alert archive / Utah / Flash Flood Warnings in 2012

Flash Flood Warning 58, NWS Salt Lake City, UT

August 23, 2012Garfield County, Wayne County, Utah

NWS Salt Lake City, UT issued this flash flood warning at Aug 23, 2012, 12:45 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 23, 2012, 12:45 PM MDT (18:45 UTC)
Expired
Aug 23, 2012, 3:45 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 18:49 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, 6.8 hours before the alert went out and 261 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 2012-08-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 191 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 2012-08-23The 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
191 J/kg
Mixed-layer CIN
-77 J/kg
Mixed-layer LCL
1007 m above ground
0-6 km bulk shear
18 kt
0-1 km storm-relative helicity
81 m²/s²
0-3 km storm-relative helicity
132 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.

124 
WGUS55 KSLC 231845
FFWSLC
UTC017-055-232145-
/O.NEW.KSLC.FF.W.0058.120823T1845Z-120823T2145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1245 PM MDT THU AUG 23 2012

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 INCLUDING SHEETS GULCH IN 
  CAPITOL REEF NATIONAL PARK. 

* UNTIL 345 PM MDT

* AT 1240 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
HEAVY RAIN FROM A THUNDERSTORM OVER THE CENTRAL PORTION OF CAPITOL 
REEF NATIONAL PARK. THIS WARNING INCLUDES SHEETS GULCH AND PORTIONS 
OF THE NOTOM ROAD. 

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.

A FLASH FLOOD WARNING MEANS THAT FLOODING IS IMMINENT OR OCCURRING.
IF YOU ARE IN THE WARNING AREA MOVE TO HIGHER GROUND IMMEDIATELY.
RESIDENTS LIVING ALONG STREAMS AND CREEKS SHOULD TAKE IMMEDIATE
PRECAUTIONS TO PROTECT LIFE AND PROPERTY. DO NOT ATTEMPT TO CROSS
SWIFTLY FLOWING WATERS OR WATERS OF UNKNOWN DEPTH BY FOOT OR BY
AUTOMOBILE.

&&

LAT...LON 3803 11123 3818 11125 3820 11108 3798 11103
      3793 11118

$$

NH
1 follow-up statement
113 
WGUS75 KSLC 232139
FFSSLC

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
339 PM MDT THU AUG 23 2012

UTC017-055-232146-
/O.EXP.KSLC.FF.W.0058.000000T0000Z-120823T2145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
GARFIELD UT-WAYNE UT-
339 PM MDT THU AUG 23 2012

...THE FLASH FLOOD WARNING WILL EXPIRE AT 345 PM MDT FOR SOUTH
CENTRAL WAYNE AND NORTH CENTRAL GARFIELD COUNTIES...

THE RAINFALL OVER THE SOUTHERN END OF CAPITOL REEF NATIONAL PARK HAS 
DIMINISHED...AS A RESULT THE FLASH FLOOD WARNING FOR THIS AREA HAS 
BEEN ALLOWED TO EXPIRE. 

ALTHOUGH RAINFALL HAS TEMPORARILY MOVED ON...IT IS ANTICIPATED THAT 
ADDITIONAL STORMS WILL MOVE THROUGH THIS AREA PROVIDING ADDITIONAL 
WATER FOR HEIGHTENED FLOWS THROUGH THE DRAINAGES.

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 3803 11123 3818 11125 3820 11108 3798 11103
      3793 11118

$$

MCINERNEY

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 23, 11:59 AM MDTFlash Flood WarningSLCSevier, Wayne3 hr
Aug 23, 2:52 PM MDTFlash Flood WarningSLCKane, San Juan6 hr

Nearby

Flash Flood Warnings in Utah, 2012Every flash flood warning in 2012

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.