Alert archive / Utah / Flash Flood Warnings in 2017

Flash Flood Warning 34, NWS Salt Lake City, UT

August 3, 2017Kane County, Washington County, Utah

NWS Salt Lake City, UT issued this flash flood warning at Aug 3, 2017, 7:02 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
Aug 3, 2017, 7:02 PM MDT (01:02 UTC)
Expired
Aug 3, 2017, 10:00 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), 37 km from the middle of the area, began a volume at 01:05 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 3, 8:15 PM MDTFLASH FLOODZion Np, UTFLOODING REPORTED ACROSS THE LOWER HALF OF THE PARK FROM ROUGHLY CANYON JUNCTION SOUTHWARD INCLUDING PINE CREEK. FLOODING ALSO REPORTED IN THE TOWNS OF SPRINGDALE AND ROCKVILLE.

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 00:00Z, 1.0 hours before the alert went out and 244 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 00:00Z on 2017-08-04Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 95 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 00:00Z on 2017-08-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -9 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
95 J/kg
Mixed-layer CIN
-46 J/kg
Mixed-layer LCL
1515 m above ground
0-6 km bulk shear
13 kt
0-1 km storm-relative helicity
-9 m²/s²
0-3 km storm-relative helicity
20 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

797 
WGUS55 KSLC 040102
FFWSLC
UTC025-053-040400-
/O.NEW.KSLC.FF.W.0034.170804T0102Z-170804T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Salt Lake City UT
702 PM MDT THU AUG 3 2017

The National Weather Service in Salt Lake City has issued a

* Flash Flood Warning for...
  Southeastern Washington County in southwestern Utah...
  West central Kane County in southern Utah...

* Until 1000 PM MDT
    
* At 700 PM MDT, Doppler radar indicated thunderstorms producing 
  heavy rain moving into Zion National Park. Flash flooding is 
  expected to begin shortly within the Zion Canyon, as well as areas 
  along Highway 9 including Pine Creek and Keyhole Canyon.

* Some locations that will experience flooding include...
  Zion National Park, Orderville, Springdale, Rockville and Mt
  Carmel.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Flooding is occurring or is imminent. It is important to know where
you are relative to streams, rivers, or creeks which can become
killers in heavy rains. Campers and hikers should avoid streams or
creeks.

&&

LAT...LON 3737 11266 3709 11265 3709 11315 3737 11313

$$

MPS
2 follow-up statements
568 
WGUS75 KSLC 040223
FFSSLC

Flash Flood Statement
National Weather Service Salt Lake City UT
823 PM MDT THU AUG 3 2017

UTC025-053-040400-
/O.CON.KSLC.FF.W.0034.000000T0000Z-170804T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Washington UT-Kane UT-
823 PM MDT THU AUG 3 2017

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1000 PM MDT FOR
SOUTHEASTERN WASHINGTON AND WEST CENTRAL KANE COUNTIES...

At 820 PM MDT,  reported heavy rain due to a thunderstorm over !** 
Zion National Park reported extensive flooding across the southern 
half of the park from roughly Canyon Junction south and west into 
the towns of Springville and Rockville. Numerous rockfalls were also 
reported. 

Although rain is winding down, residual runoff will continue to 
result in flash flooding across the area. Some locations that will 
experience flooding include... Zion National Park, Orderville, 
Springdale, Rockville and Mt Carmel. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Flooding is occurring or is imminent. It is important to know where
you are relative to streams, rivers, or creeks which can become
killers in heavy rains. Campers and hikers should avoid streams or
creeks.

&&

LAT...LON 3737 11266 3709 11265 3709 11315 3737 11313

$$

MPS
557 
WGUS75 KSLC 040400
FFSSLC

Flash Flood Statement
National Weather Service Salt Lake City UT
1000 PM MDT THU AUG 3 2017

UTC025-053-040407-
/O.EXP.KSLC.FF.W.0034.000000T0000Z-170804T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Washington UT-Kane UT-
1000 PM MDT THU AUG 3 2017

...THE FLASH FLOOD WARNING FOR SOUTHEASTERN WASHINGTON AND WEST
CENTRAL KANE COUNTIES WILL EXPIRE AT 1000 PM MDT...

The heavy rain has ended in the Zion National Park area. However, 
creeks and streams as well as normally dry washes will continue to 
see high flows through late tonight as flood waters from earlier 
heavy rain gradually recede. Please continue to heed any remaining 
road and trail closures.

LAT...LON 3737 11266 3709 11265 3709 11315 3737 11313

$$

LC

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 4, 10:01 AM MDTFlash Flood WatchSLC14 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.