Alert archive / Utah / Flash Flood Warnings in 2011

Flash Flood Warning 52, NWS Salt Lake City, UT

September 14, 2011Kane County, Washington County, Utah

NWS Salt Lake City, UT issued this flash flood warning at Sep 14, 2011, 2:40 PM MDT for Kane County, Washington 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
Sep 14, 2011, 2:40 PM MDT (20:40 UTC)
Expired
Sep 14, 2011, 5:45 PM MDT
In force
3 hr
Issued by
NWS Salt Lake City, UT
Area
Storm-based polygon
Flood severity
None

Counties Kane County, UT, Washington County, UT

The radar

The Cedar City radar (KICX), 43 km from the middle of the area, began a volume at 20:40 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

TimeReportWhereRemark
Sep 14, 3:35 PM MDTFLASH FLOOD4 E Zion Np, UTPARK RANGERS REPORTED FLASH FLOODING ALONG PINE CREEK 7 TO 8 FEET DEEP...AND ALONG THE EAST FORK OF THE VIRGIN RIVER 3 TO 4 FEET DEEP. ADDITIONALLY NUMEROUS WATERFALLS HAVE FORMED THROUGHOUT ZION CANYON.

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

The nearest sounding before it

Flgstf/Belemont, AZ (KFGZ), launched 12:00Z, 8.7 hours before the alert went out and 243 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, Flgstf/Belemont, AZ at 12:00Z on 2011-09-14Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 224 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Flgstf/Belemont, AZ at 12:00Z on 2011-09-14The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 45 square meters per square second.19395878Sfc1 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
224 J/kg
Mixed-layer CIN
-8 J/kg
Mixed-layer LCL
729 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
45 m²/s²
0-3 km storm-relative helicity
64 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

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

797 
WGUS55 KSLC 142040
FFWSLC
UTC025-053-142345-
/O.NEW.KSLC.FF.W.0052.110914T2040Z-110914T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
240 PM MDT WED SEP 14 2011

THE NATIONAL WEATHER SERVICE IN SALT LAKE CITY HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  WEST CENTRAL KANE COUNTY IN UTAH
  EAST CENTRAL WASHINGTON COUNTY IN UTAH

* UNTIL 545 PM MDT

* AT 500 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  THUNDERSTORMS CAPABLE OF PRODUCING VERY HEAVY RAIN OVER THE WARNED
  AREA.

* LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO ZION       
  NATIONAL PARK AND STATE ROUTE 9.

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 3725 11306 3733 11291 3724 11283 3727 11276
      3723 11269 3717 11276 3712 11287 3710 11300
      3712 11308 3721 11312 3723 11311

$$

ROGOWSKI
2 follow-up statements
742 
WGUS75 KSLC 142147
FFSSLC

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
347 PM MDT WED SEP 14 2011

UTC025-053-142345-
/O.CON.KSLC.FF.W.0052.000000T0000Z-110914T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
WASHINGTON UT-KANE UT-
347 PM MDT WED SEP 14 2011

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 545 PM MDT FOR WEST
CENTRAL KANE AND EAST CENTRAL WASHINGTON COUNTIES...

AT 335 PM MDT...PARK RANGERS REPORTED FLASH FLOODING ALONG PINE 
CREEK 7 TO 8 FEET DEEP...AND ALONG THE EAST FORK OF THE VIRGIN  
RIVER 3 TO 4 FEET DEEP. ADDITIONALLY NUMEROUS WATERFALLS           
HAVE FORMED THROUGHOUT ZION CANYON.

THE THUNDERSTORMS WHICH CAUSED THE FLASH FLOODING HAVE MOVED TO THE 
NORTH...BUT PERIODS OF RAINFALL AND THE FLASH FLOOD THREAT WILL 
CONTINUE INTO THE EARLY EVENING HOURS.

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO ZION NATIONAL
PARK AND STATE ROUTE 9.

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 3725 11306 3733 11291 3724 11283 3727 11276
      3723 11269 3717 11276 3712 11287 3710 11300
      3712 11308 3721 11312 3723 11311

$$

ROGOWSKI
442 
WGUS75 KSLC 142343
FFSSLC

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
543 PM MDT WED SEP 14 2011

UTC025-053-142348-
/O.EXP.KSLC.FF.W.0052.000000T0000Z-110914T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
WASHINGTON UT-KANE UT-
543 PM MDT WED SEP 14 2011

...THE FLASH FLOOD WARNING WILL EXPIRE AT 545 PM MDT FOR WEST CENTRAL
KANE AND EAST CENTRAL WASHINGTON COUNTIES...

THE FLASH FLOOD WARNING WHICH WAS IN EFFECT FOR WEST CENTRAL KANE 
AND EAST CENTRAL WASHINGTON COUNTIES INCLUDING ZION NATIONAL PARK 
WILL BE ALLOWED TO EXPIRE AT 545 PM. FLASH FLOODING FROM EARLIER 
THUNDERSTORMS HAS WORKED ITS WAY INTO THE MAIN STEM OF THE VIRGIN 
RIVER.

LAT...LON 3725 11306 3733 11291 3724 11283 3727 11276
      3723 11269 3717 11276 3712 11287 3710 11300
      3712 11308 3721 11312 3723 11311

$$

ROGOWSKI

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 14, 2:23 PM MDTFlash Flood WarningSLCWashington6 hr
Sep 14, 3:30 PM MDTFlash Flood WarningSLCKane4 hr
Sep 14, 3:32 PM MDTSpecial Weather StatementSLC43 min
Sep 14, 5:09 PM MDTFlash Flood WarningSLCKane3 hr

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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.