Alert archive / Utah / Flash Flood Warnings in 2017

Flash Flood Warning 10, NWS Salt Lake City, UT

July 19, 2017Emery County, Sevier County, Wayne County, Utah

NWS Salt Lake City, UT issued this flash flood warning at Jul 19, 2017, 4:00 PM MDT for Emery County, Sevier 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
Jul 19, 2017, 4:00 PM MDT (22:00 UTC)
Expired
Jul 19, 2017, 7:00 PM MDT
In force
3 hr
Issued by
NWS Salt Lake City, UT
Area
Storm-based polygon
Flood severity
None

Counties Emery County, UT, Sevier County, UT, Wayne County, UT

The radar

The Cedar City radar (KICX), 166 km from the middle of the area, began a volume at 22:03 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, 10.0 hours before the alert went out and 254 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 2017-07-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 8 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 2017-07-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 23 square meters per square second.1939Sfc1 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
8 J/kg
Mixed-layer CIN
-341 J/kg
Mixed-layer LCL
2559 m above ground
0-6 km bulk shear
1 kt
0-1 km storm-relative helicity
23 m²/s²
0-3 km storm-relative helicity
-17 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

761 
WGUS55 KSLC 192200
FFWSLC
UTC015-041-055-200100-
/O.NEW.KSLC.FF.W.0010.170719T2200Z-170720T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Salt Lake City UT
400 PM MDT WED JUL 19 2017

The National Weather Service in Salt Lake City has issued a

* Flash Flood Warning for...
  Northwestern Wayne County in southern Utah...
  Southwestern Emery County in central Utah...
  Southeastern Sevier County in central Utah...

* Until 700 PM MDT
    
*  At 354 PM MDT, Doppler radar indicated thunderstorms producing 
   heavy rain over Cathedral Valley in Capitol Reef National Park.
   Up to two inches of rain has already fallen and additional 
   rainfall is expected. Flash flooding is imminent and is expected 
   to impact the Polk Creek and Deep Creek drainages as well as the 
   Cathedral Campground. 

* Some locations that will experience flooding include...
  Capitol Reef National Park.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Excessive runoff from heavy rainfall will cause flooding of small 
creeks and streams and normally dry washes.

Remain alert for flooding even in locations not receiving rain. Dry
washes, streams, and rivers can become raging killer currents in a
matter of minutes, even from distant rainfall.

&&

LAT...LON 3827 11120 3838 11146 3851 11152 3853 11131
      3850 11130 3849 11124 3843 11118 3828 11110

$$

RG
2 follow-up statements
995 
WGUS75 KSLC 192322
FFSSLC

Flash Flood Statement
National Weather Service Salt Lake City UT
522 PM MDT WED JUL 19 2017

UTC015-041-055-200100-
/O.CON.KSLC.FF.W.0010.000000T0000Z-170720T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Wayne UT-Emery UT-Sevier UT-
522 PM MDT WED JUL 19 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 700 PM MDT FOR
NORTHWESTERN WAYNE...SOUTHWESTERN EMERY AND SOUTHEASTERN SEVIER
COUNTIES...

At 513 PM MDT, Doppler radar indicated thunderstorms continued to 
produce heavy rain across the Cathedral Valley portion of Capitol 
Reef National Park.  Radar estimates indicate that 2 to 3 inches of 
rain has fallen in the headwaters of the Polk Creek and Deep Creek 
drainages that feed into Capitol Reef.  

The rainfall is likely to cause significant flooding in these 
drainages as well as the Cathedral Valley Campground.  Individuals 
in northern Capital Reef National Park should move to higher ground! 

Some locations that will experience flooding include...
Capitol Reef National Park.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

Remain alert for flooding even in locations not receiving rain. Dry
washes, streams, and rivers can become raging killer currents in a
matter of minutes, even from distant rainfall.

&&

LAT...LON 3827 11120 3838 11146 3851 11152 3853 11131
      3850 11130 3849 11124 3843 11118 3828 11110

$$
422 
WGUS75 KSLC 200100
FFSSLC

Flash Flood Statement
National Weather Service Salt Lake City UT
700 PM MDT WED JUL 19 2017

UTC015-041-055-200105-
/O.EXP.KSLC.FF.W.0010.000000T0000Z-170720T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Wayne UT-Emery UT-Sevier UT-
700 PM MDT WED JUL 19 2017

...THE FLASH FLOOD WARNING FOR NORTHWESTERN WAYNE...SOUTHWESTERN
EMERY AND SOUTHEASTERN SEVIER COUNTIES WILL EXPIRE AT 700 PM MDT...

The heavy rain has ended and the flash flood warning will be allowed 
to expire. While significant flash flooding is no longer expected 
area creeks and streams and normally dry washes may continue to run 
high for several hours and some roads may be impassable.

LAT...LON 3827 11120 3838 11146 3851 11152 3853 11131
      3850 11130 3849 11124 3843 11118 3828 11110

$$

RG

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 18, 6:13 PM MDTSevere Thunderstorm WarningSLCIron32 min
Jul 19, 2:17 AM MDTFlash Flood WarningSLCKane4 hr
Jul 19, 1:29 PM MDTFlash Flood WarningSLCSevier3 hr
Jul 19, 1:36 PM MDTSpecial Weather StatementSLCPiute24 min
Jul 19, 2:43 PM MDTSevere Thunderstorm WarningSLCUtah, Wasatch32 min
Jul 19, 3:21 PM MDTSpecial Weather StatementSLCUtah39 min
Jul 19, 3:35 PM MDTAreal Flood AdvisorySLCUtah55 min
Jul 19, 5:42 PM MDTFlash Flood WarningSLCWayne3 hr

Nearby

Flash Flood Warnings in Utah, 2017Every flash flood warning in 2017

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.