Flash Flood Warning 70, NWS Salt Lake City, UT

858 
WGUS75 KSLC 112008
FFSSLC

Flash Flood Statement
National Weather Service Salt Lake City UT
208 PM MDT Tue Aug 11 2026

UTC031-112215-
/O.CON.KSLC.FF.W.0070.000000T0000Z-260811T2215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Piute UT-
208 PM MDT Tue Aug 11 2026

...FLASH FLOOD WARNING FOR THE COTTONWOOD BURN SCAR REMAINS IN EFFECT
UNTIL 415 PM MDT THIS AFTERNOON FOR WEST CENTRAL PIUTE COUNTY...

At 208 PM MDT, Doppler radar indicated thunderstorms producing heavy
rain over the Cottonwood Burn Scar in Piute County. Between 0.5 and 1
inch of rain have fallen, with the heaviest rainfall occurring over
Gold Gulch and Ten Mile Creek areas. Flash flooding is already
ongoing, and has resulted in a closure of US-89 near mile post 173.

Excessive rainfall over the burn scar will result in debris flow
moving through the Gold Gulch and Ten Mile Creek, and possibly
Cottonwood Gulch. The debris flow can consist of rock, mud,
vegetation and other loose materials.

HAZARD...Life threatening flash flooding. Thunderstorms producing
         flash flooding in and around the Cottonwood Burn Scar in
         Piute County, with flows impacting US 89 between mile
         markers 171 to 176.

SOURCE...Radar indicated.

IMPACT...Life threatening flash flooding of areas in and around the
         Cottonwood Burn Scar in Piute County.

Some locations that will experience flash flooding include...
  US 89 between mile markers 171 to 176 in.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.

Move to higher ground now. Act quickly to protect your life.

Stay away or be swept away. River banks and culverts can become
unstable and unsafe.

&&

LAT...LON 3837 11236 3834 11233 3830 11232 3834 11219
      3842 11222

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

Webber

879 
WGUS75 KSLC 112212
FFSSLC

Flash Flood Statement
National Weather Service Salt Lake City UT
412 PM MDT Tue Aug 11 2026

UTC031-112222-
/O.EXP.KSLC.FF.W.0070.000000T0000Z-260811T2215Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Piute UT-
412 PM MDT Tue Aug 11 2026

...FLASH FLOOD WARNING FOR THE COTTONWOOD BURN SCAR WILL EXPIRE AT
415 PM MDT THIS AFTERNOON FOR WEST CENTRAL PIUTE COUNTY...

The heavy rain has ended. Additional flooding is no longer expected
to pose a threat. US-89 near mile post 173 remains closed at this
time. Please continue to heed the remaining road closure and check
UDOT traffic website for further information.

&&

LAT...LON 3837 11236 3834 11233 3830 11232 3834 11219
      3842 11222

$$

Webber

Area Forecast Discussion
National Weather Service Salt Lake City UT
1226 PM MDT Tue Aug 11 2026

.KEY MESSAGES...

- A marginal risk of excessive rainfall will continue across much
  of Utah through at least Friday. This risk expands further north
  on Thursday and Friday.

- Temperatures will decrease 10-15 degrees by the end of the week
  with slightly drier air pushing into the area by the weekend.

&&

.DISCUSSION...Monsoon moisture will remain in place through Friday
as the ridge responsible for this influx gradually shifts to the
east. As this ridge shifts to the east a weak trough will push
into the western CONUS. This will enhance lift on Thursday and
Friday to expand widespread convection across all of Utah and SW
Wyoming. The flash flooding risk will gradually expand into
northern Utah Thursday and Friday with slot canyons, normal dry
washes, urban areas, and recent burn scars will be most
susceptible to flooding.

Convection will develop each afternoon and persist through the
early evening before gradually diminishing overnight. The caveat
with this will be for the potential for nocturnal convection.
Guidance continues to hint at lingering moisture overnight, such
as tonight across northern Utah, but models struggle to capture
these features accurately. The most likely time for nocturnal
activity will come Thursday and Friday as forcing increases.
Temperatures will also trend down 10-15 degrees with the increased
cloud coverage and cooling temperatures aloft.

Slightly drier air moves into the area this weekend with most of
the diurnal convection confined to the higher terrain. Moisture
moves back into the area next week as the ridge re-positions
itself over the Four Corners. This active pattern looks to remain
across the area, in some form, through the next couple of weeks.

&&

.AVIATION...

KSLC...Winds will remain southerly until a transition to
northwesterly expected between 19-20z. There is a 25-35% chance of
showers and thunderstorms in the Salt Lake Valley between 20Z-06Z,
and any shower or thunderstorm will be capable of producing gusty
and erratic winds. VFR conditions will largely prevail, but can't
rule out reductions in VIS from heavy rain and/or blowing dust if a
thunderstorm core passes over the terminal.

REST OF UTAH AND SOUTHWEST WYOMING...Terrain-driven showers and
thunderstorms will be in place this afternoon and evening, with some
of this activity surviving off of the terrain and moving towards the
northeast. Any shower or thunderstorm will be capable of producing
briefly heavy rain and gusty/erratic winds. Latest high-resolution
models insist that a complex of showers and thunderstorms will
overspread northern Utah during the late evening hours before moving
across northeast Utah and SW Wyoming during the late evening and
early morning hours Wednesday.

&&

.FIRE WEATHER...Monsoon moisture will continue to surge into Utah
through the remainder of the week with storms developing during the
afternoon and weakening late evening and overnight. Some nocturnal
activity will remain and persist, but the details of when and where
with these storms will likely remain uncertain until the day of.
Storms will be capable of producing gusty and erratic outflow winds
along with frequent lightning and brief heavy rain.

A storm system approaches by Thursday that will increase southwesterly
winds, but RH will remain elevated. This storm system will help to
expand precipitation across most of northern Utah, persisting through
Friday. Temperatures will cool 10-15 degrees across the area as this
system brings a cooler airmass. By the weekend, a slightly drier
airmass will limit most of the diurnal storms to the high terrain
before better moisture returns next week.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...None.
WY...None.
&&

PUBLIC...Mahan
AVIATION...ADeSmet
FIRE WEATHER...Mahan

For more information from NOAA's National Weather Service visit...
http://weather.gov/saltlakecity