Alert archive / Utah / Flash Flood Warnings in 2019

Flash Flood Warning 13, NWS Salt Lake City, UT

August 10, 2019Utah County, Utah

NWS Salt Lake City, UT issued this flash flood warning at Aug 10, 2019, 3:39 PM MDT for Utah County, Utah. It was in force for 111 min. 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 10, 2019, 3:39 PM MDT (21:39 UTC)
Expired
Aug 10, 2019, 5:30 PM MDT
In force
111 min
Issued by
NWS Salt Lake City, UT
Area
Storm-based polygon
Flood severity
None

County Utah County, UT

The radar

The Salt Lake City radar (KMTX), 168 km from the middle of the area, began a volume at 21:42 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 10, 3:52 PM MDTFLASH FLOOD2 Nne Birdseye, UTFLASH FLOODING REPORTED FROM DEPT OF HIGHWAY DISPATCH. DRAINAGE DITCHES SURGED RESULTING IN STANDING WATER ON US-89 NEAR BIRDSEYE.

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

The nearest sounding before it

Salt Lake City I, UT (KSLC), launched 12:00Z, 9.7 hours before the alert went out and 100 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, Salt Lake City I, UT at 12:00Z on 2019-08-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Salt Lake City I, UT at 12:00Z on 2019-08-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 92 square meters per square second.1939587897Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
3367 m above ground
0-6 km bulk shear
30 kt
0-1 km storm-relative helicity
92 m²/s²
0-3 km storm-relative helicity
104 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

986 
WGUS55 KSLC 102139
FFWSLC
UTC049-102330-
/O.NEW.KSLC.FF.W.0013.190810T2139Z-190810T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Salt Lake City UT
339 PM MDT Sat Aug 10 2019

The National Weather Service in Salt Lake City has issued a

* Flash Flood Warning for...
  South central Utah County in northern Utah...

* Until 530 PM MDT
    
* At 335 PM MDT, Doppler radar indicated a thunderstorm producing 
  heavy rain over the Pole Creek burn scar near the town of Birdseye 
  along highway 89. Up to one half inch of rain has fallen so far, 
  estimated by radar. Flash flooding is expected to begin shortly.

* Some locations that will experience flooding include...
  Birdseye.

Excessive rainfall over the Pole Creek burn scar will result in 
debris flow moving through highway 89 through the town of Birdseye. 

The debris flow can consist of rock, mud, vegetation and other loose 
materials.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If a debris flow has occurred it is important to realize that the
runout area remains very dangerous. Additional debris flows may occur
within minutes of the original flow. Please remain vigilant and be
prepared to take swift action.

A Flash Flood Warning means that flooding is imminent or occurring.
If you are in the warned area move to higher ground immediately.
Residents living along streams and creeks should take immediate
precautions to protect life and property.

&&

LAT...LON 3995 11150 3994 11149 3988 11149 3988 11157
      3996 11156

$$

Dewey
2 follow-up statements
886 
WGUS75 KSLC 102240
FFSSLC

Flash Flood Statement
National Weather Service Salt Lake City UT
440 PM MDT Sat Aug 10 2019

UTC049-102330-
/O.CON.KSLC.FF.W.0013.000000T0000Z-190810T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Utah UT-
440 PM MDT Sat Aug 10 2019

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 530 PM MDT FOR
SOUTH CENTRAL UTAH COUNTY...

At 437 PM MDT, Doppler radar indicated thunderstorms producing heavy 
rain have moved out of the area, however flash flooding along 
highway 89 near Birdseye and across the Pole Creek burn scar may be 
at the peak of intensity. This is likely resulting in flash 
flooding. Debris and mud flow are possible across roadways.

Some locations that will experience flooding include...
Birdseye and highway 89.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If a debris flow has occurred it is important to realize that the
runout area remains very dangerous. Additional debris flows may occur
within minutes of the original flow. Please remain vigilant and be
prepared to take swift action.

A Flash Flood Warning means that flooding is imminent or occurring.
If you are in the warned area move to higher ground immediately.
Residents living along streams and creeks should take immediate
precautions to protect life and property.

&&

LAT...LON 3995 11150 3994 11149 3988 11149 3988 11157
      3996 11156

$$

Dewey
756 
WGUS75 KSLC 102330
FFSSLC

Flash Flood Statement
National Weather Service Salt Lake City UT
530 PM MDT Sat Aug 10 2019

UTC049-102338-
/O.EXP.KSLC.FF.W.0013.000000T0000Z-190810T2330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Utah UT-
530 PM MDT Sat Aug 10 2019

...THE FLASH FLOOD WARNING FOR SOUTH CENTRAL UTAH COUNTY WILL EXPIRE
AT 530 PM MDT...

The heavy rain has ended over the warned area. Debris flows are no 
longer expected to pose a significant threat to the area. 

LAT...LON 3995 11150 3994 11149 3988 11149 3988 11157
      3996 11156

$$

mconger

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 9, 6:55 PM MDTSevere Thunderstorm WarningSLCBox Elder, Tooele50 min

Nearby

Flash Flood Warnings in Utah, 2019Every flash flood warning in 2019

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.