Alert archive / Utah / Flash Flood Warnings in 2012

Flash Flood Warning 12, NWS Salt Lake City, UT

July 16, 2012Kane County, Washington County, Utah

NWS Salt Lake City, UT issued this flash flood warning at Jul 16, 2012, 1:49 PM MDT for Kane County, Washington County, Utah. It was in force for 4 hr. 2 reports 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
Jul 16, 2012, 1:49 PM MDT (19:49 UTC)
Expired
Jul 16, 2012, 5:45 PM MDT
In force
4 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), 40 km from the middle of the area, began a volume at 19:49 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.

What was reported inside it

TimeReportWhereRemark
Jul 16, 5:10 PM MDTFLASH FLOODZion Np, UTFLASH FLOOD OCCURRING IN LA VERKIN CREEK...SPRY CANYON AND NUMEROUS OTHER DRAINAGES WITHIN ZION NATIONAL PARK.
Jul 16, 5:19 PM MDTFLASH FLOODZion Np, UTFLASH FLOOD OCCURRING IN LA VERKIN CREEK...SPRY CANYON AND NUMEROUS OTHER DRAINAGES WITHIN ZION NATIONAL PARK.

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

The nearest sounding before it

Las Vegas, NV (KVEF), launched 12:00Z, 7.8 hours before the alert went out and 247 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, Las Vegas, NV at 12:00Z on 2012-07-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 610 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, Las Vegas, NV at 12:00Z on 2012-07-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 27 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
610 J/kg
Mixed-layer CIN
-168 J/kg
Mixed-layer LCL
1601 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
27 m²/s²
0-3 km storm-relative helicity
96 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.5

Open this sounding in Storm Lab

The text

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

124 
WGUS55 KSLC 161949
FFWSLC
UTC025-053-162345-
/O.NEW.KSLC.FF.W.0012.120716T1949Z-120716T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
149 PM MDT MON JUL 16 2012

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 INCLUDING ZION NATIONAL PARK

* UNTIL 545 PM MDT

* AT 145 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  VERY HEAVY RAIN FROM THUNDERSTORMS ACROSS EASTERN WASHINGTON AND 
  WESTERN KANE COUNTIES. 

* FLASH FLOODING IS EXPECTED ACROSS THE EAST FORK OF THE VIRGIN 
  RIVER...AS WELL AS NUMEROUS SLOT CANYONS WITHIN AND AROUND ZION 
  NATIONAL PARK INCLUDING THE ZION NARROWS. 

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 3737 11316 3736 11269 3707 11274 3707 11316

$$

MPS
2 follow-up statements
804 
WGUS75 KSLC 162128
FFSSLC

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
328 PM MDT MON JUL 16 2012

UTC025-053-162345-
/O.CON.KSLC.FF.W.0012.000000T0000Z-120716T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
WASHINGTON UT-KANE UT-
328 PM MDT MON JUL 16 2012

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

AT 320 PM MDT...ZION NATIONAL PARK RANGERS REPORTED VERY HEAVY 
RAINFALL HAD OCCURRED EARLIER OVER THE PARK. EXCESSIVE RUNOFF FROM 
THIS RAINFALL IS LIKELY STILL MAKING ITS WAY THROUGH SLOT CANYONS 
AND DRAINAGES...INCLUDING SPRY CANYON...PINE CREEK...AND THE EAST 
FORK OF THE VIRGIN. THIS RUNOFF WILL LIKELY CONTINUE TO MAKE ITS WAY 
THROUGH THESE DRAINAGES THROUGH THE REMAINDER OF THE AFTERNOON. 

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 3737 11316 3736 11269 3707 11274 3707 11316

$$

MPS
407 
WGUS75 KSLC 162233
FFSSLC

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
433 PM MDT MON JUL 16 2012

UTC025-053-162345-
/O.CON.KSLC.FF.W.0012.000000T0000Z-120716T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
WASHINGTON UT-KANE UT-
433 PM MDT MON JUL 16 2012

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

AT 421 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
ADDITIONAL THUNDERSTORMS CAPABLE OF PRODUCING HEAVY RAINFALL MOVING 
TOWARD ZION NATIONAL PARK. THESE STORMS WILL LIKELY MOVE INTO THE 
PARK BY 5 PM...AND PRODUCE ADDITIONAL FLASH FLOODING. 

LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO ZION NATIONAL
PARK

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 3737 11316 3736 11269 3707 11274 3707 11316

$$

MPS

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 15, 6:20 PM MDTSevere Thunderstorm WarningSLCEmery55 min
Jul 15, 8:06 PM MDTFlash Flood WarningSLCWashington4 hr
Jul 16, 1:04 PM MDTFlash Flood WarningSLCWayne3 hr
Jul 16, 1:13 PM MDTFlash Flood WarningSLCWashington11 hr
Jul 16, 1:24 PM MDTSpecial Weather StatementSLCTooele66 min
Jul 16, 1:37 PM MDTSevere Thunderstorm WarningSLCKane38 min
Jul 16, 2:00 PM MDTSevere Thunderstorm WarningSLCBox Elder, Tooele43 min
Jul 16, 2:20 PM MDTSpecial Weather StatementSLC70 min
Jul 16, 2:26 PM MDTSpecial Weather StatementSLC49 min
Jul 16, 2:33 PM MDTSevere Thunderstorm WarningSLCKane27 min
Jul 16, 2:55 PM MDTFlash Flood WarningSLCKane3 hr
Jul 16, 3:01 PM MDTSpecial Weather StatementSLC44 min
Jul 16, 3:24 PM MDTSpecial Weather StatementSLCCarbon51 min
Jul 16, 4:10 PM MDTSevere Thunderstorm WarningSLCWashington50 min
Jul 16, 4:38 PM MDTSpecial Weather StatementSLCWeber67 min
Jul 16, 4:49 PM MDTSpecial Weather StatementSLC26 min
Jul 16, 4:54 PM MDTFlash Flood WarningSLCUtah50 min
Jul 16, 4:56 PM MDTSevere Thunderstorm WarningSLCWashington49 min
Jul 16, 5:00 PM MDTSpecial Weather StatementSLCRich60 min
Jul 16, 5:01 PM MDTFlash Flood WarningSLCWashington4 hr
Jul 16, 5:10 PM MDTSevere Thunderstorm WarningSLCSalt Lake, Utah50 min
Jul 16, 5:19 PM MDTSevere Thunderstorm WarningSLCDavis, Salt Lake, Tooele41 min
Jul 16, 5:22 PM MDTSpecial Weather StatementSLCCache38 min
Jul 16, 5:28 PM MDTFlash Flood WarningSLCKane, Washington6 hr
Jul 16, 5:54 PM MDTSpecial Weather StatementSLCDavis, Salt Lake51 min

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