Alert archive / Utah / Flash Flood Warnings in 2012

Flash Flood Warning 48, NWS Salt Lake City, UT

August 19, 2012Kane County, Utah

NWS Salt Lake City, UT issued this flash flood warning at Aug 19, 2012, 2:41 PM MDT for Kane County, Utah. It was in force for 9 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
Aug 19, 2012, 2:41 PM MDT (20:41 UTC)
Expired
Aug 19, 2012, 11:45 PM MDT
In force
9 hr
Issued by
NWS Salt Lake City, UT
Area
Storm-based polygon
Flood severity
None

County Kane County, UT

The radar

The Cedar City radar (KICX), 81 km from the middle of the area, began a volume at 20:42 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
Aug 19, 6:13 PM MDTFLASH FLOOD14 W Big Water, UTLARGE FLASH FLOOD ALONG THE PARIA RIVER. SPOTTER ESTIMATED FIRST 200 TO 300 YARDS OF FLOOD WAS COMPOSED OF DEBRIS INCLUDING TREES AND LOGS.

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 229 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 2012-08-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 155 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Flgstf/Belemont, AZ at 12:00Z on 2012-08-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -30 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
155 J/kg
Mixed-layer CIN
-108 J/kg
Mixed-layer LCL
1712 m above ground
0-6 km bulk shear
14 kt
0-1 km storm-relative helicity
-30 m²/s²
0-3 km storm-relative helicity
-32 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.

221 
WGUS55 KSLC 192041
FFWSLC
UTC025-200545-
/O.NEW.KSLC.FF.W.0048.120819T2041Z-120820T0545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
241 PM MDT SUN AUG 19 2012

THE NATIONAL WEATHER SERVICE IN SALT LAKE CITY HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CENTRAL KANE COUNTY IN UTAH INCLUDING THE PARIA 
  RIVER...COTTONWOOD CREEK AND BUCKSKIN GULCH. 

* UNTIL 1145 PM MDT

* AT 238 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  HEAVY RAIN HAS FALLEN ACROSS THE HEADWATERS OF THE PARIA 
  RIVER...WITH RADAR ESTIMATES IN EXCESS OF ONE INCH. A

* AN ADDITIONAL ONE HALF TO ONE INCH OF RAINFALL IS EXPECTED ACROSS 
  THIS AREA THROUGH 4 PM...WITH LOCALLY HIGHER AMOUNTS POSSIBLE.  

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 3743 11226 3753 11176 3700 11178 3700 11208

$$

MPS
3 follow-up statements
888 
WGUS75 KSLC 192221
FFSSLC

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
421 PM MDT SUN AUG 19 2012

UTC025-200545-
/O.CON.KSLC.FF.W.0048.000000T0000Z-120820T0545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
KANE UT-
421 PM MDT SUN AUG 19 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1145 PM MDT FOR THE 
PARIA RIVER DRAINAGE IN CENTRAL KANE COUNTY...

AT 413 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
RAINFALL TOTALS IN EXCESS OF 3 INCHES HAS FALLEN ACROSS THE 
HEADWATERS OF THE PARIA RIVER WITHIN THE COTTONWOOD CREEK DRAINAGE. 

RUNOFF FROM THIS EXCESSIVE RAINFALL IS LIKELY RESULTING IN A 
SIGNIFICANT FLASH FLOOD ALONG COTTONWOOD CREEK NEAR ITS CONFLUENCE 
WITH THE PARIA RIVER AT THIS TIME. THIS FLOOD IS EXPECTED TO 
CONTINUE DOWN THE PARIA RIVER...AND REACH THE AREA NEAR HIGHWAY 89 
LATER THIS EVENING. 

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 3743 11226 3753 11176 3700 11178 3700 11208

$$

MPS
394 
WGUS75 KSLC 200058
FFSSLC

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
658 PM MDT SUN AUG 19 2012

UTC025-200545-
/O.CON.KSLC.FF.W.0048.000000T0000Z-120820T0545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
KANE UT-
658 PM MDT SUN AUG 19 2012

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1145 PM MDT FOR THE 
PARIA RIVER IN CENTRAL KANE COUNTY...

AT 613 PM MDT...A TRAINED WEATHER SPOTTER REPORTED A LARGE FLASH 
FLOOD MOVING DOWN THE PARIA RIVER...AND PASSING UNDER THE BRIDGE 
ALONG HIGHWAY 89. THIS FLOOD IS RESULTING FROM A LARGE AREA OF 2 TO 
3 INCHES OF RAIN WHICH OCCURRED EARLIER IN THE AFTERNOON ACROSS THE 
HEADWATERS OF THE PARIA RIVER. THIS FLOOD WAVE WILL CONTINUE TO MAKE 
ITS WAY DOWN THE PARIA RIVER DRAINAGE THROUGH THE REMAINDER OF THE 
EVENING HOURS. 

THIS THUNDERSTORM WITH EXCESSIVE RAIN WILL OTHERWISE REMAIN OVER
MAINLY RURAL AREAS OF THE INDICATED COUNTY.

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 3743 11226 3753 11176 3700 11178 3700 11208

$$

MPS
335 
WGUS75 KSLC 200543
FFSSLC

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
1143 PM MDT SUN AUG 19 2012

UTC025-200550-
/O.EXP.KSLC.FF.W.0048.000000T0000Z-120820T0545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
KANE UT-
1143 PM MDT SUN AUG 19 2012

...THE FLASH FLOOD WARNING WILL EXPIRE AT 1145 PM MDT FOR CENTRAL 
KANE COUNTY...SPECIFICALLY FOR THE PARIA RIVER

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.

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 3743 11226 3753 11176 3700 11178 3700 11208

$$

MERRILL

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 19, 2:53 AM MDTFlash Flood WatchSLC19 hr
Aug 19, 3:52 PM MDTFlash Flood WarningSLCKane4 hr
Aug 19, 4:29 PM MDTFlash Flood WarningSLCWashington3 hr
Aug 19, 4:39 PM MDTFlash Flood WarningSLCGarfield3 hr
Aug 19, 4:59 PM MDTFlash Flood WarningSLCKane, Washington4 hr
Aug 19, 5:38 PM MDTFlash Flood WarningSLCWashington4 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.