Utah, 2025

Flash Flood and Damaging Winds in Utah, August 22 to 24, 2025

August 22 to 24, 2025 · NWS SLC · 8 events in 2 counties and zones

Showers and thunderstorms brought mainly gusty winds.

Where it happened

Every event with a place to put it. Tap one for its entry below.

  • Tornadoes
  • Tropical storms and surge
  • Floods
  • Wind
  • Hail
  • Winter weather
  • Heat and drought
  • Cold
  • Fire, smoke and dust
  • Marine and coastal
  • Other

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The toll

Deaths
0
Injuries
0
Property damage
None recorded
Crop damage
None recorded
Events
8

Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.

What happened

The episode as NWS SLC wrote it up.

Showers and thunderstorms brought mainly gusty winds.

What forecasters said that day

The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Salt Lake City, UT wrote its last area forecast discussion before the first event at Aug 22, 2:17 PM MST, 2 hours 13 minutes earlier.

Area forecast discussion, Aug 22, 2:17 PM MST, 2 hours 13 minutes before
Area Forecast Discussion
National Weather Service Salt Lake City UT
317 PM MDT Fri Aug 22 2025

.SYNOPSIS...With high pressure centered over the Four Corners,
monsoon moisture will gradually spread northward into Utah and
southwest Wyoming through early next week. This will bring
increased coverage of showers and thunderstorms, the potential for
flash flooding, and gradually less hot temperatures.

&&

.SHORT TERM (Through 12Z/6AM Sunday)...As high pressure continues
to nudge westward, moisture is increasing statewide within overall
southerly flow, with PWATs reaching around 0.8-1.1" this
afternoon. Scattered showers and thunderstorms have developed
mainly over higher terrain, with only isolated outflow winds up
to 45 mph observed; instead, we have transitioned more towards a
flash flood regime, perhaps moreso than high-res guidance
initially suggested.

Moisture will further increase across the area heading into
tomorrow, with a secondary moisture push arriving late Saturday
into Sunday. Thus, tomorrow looks to be similar to today, albeit
with a slightly higher flash flood threat and lower dry microburst
threat. While model soundings still show a shallower dry layer at
the surface both today and tomorrow afternoons, slow storm
motions, modest instability, and above-normal PWATs will combine
for this increased threat of localized flash flooding,
particularly for prone areas like slot canyons or areas near
recent burn scars.

.LONG TERM (After 12Z/6AM Sunday), Issued 522 AM MDT...
Monsoonal moisture is expected to become especially pronounced
across the entirety of Utah and southwest Wyoming on Sunday into
early next week, with PWAT anomalies pushing 150-200% of normal
areawide. As such, expect widespread coverage of showers and
thunderstorms each day, with this amount of moisture in the column
favorable for locally heavy rainfall under stronger cores. The
Weather Prediction Center continues to carry a Marginal risk
(level 1 of 4) for excessive rainfall across the entire forecast
area through at least Tuesday. Those with outdoor plans should
continue to monitor the forecast given the associated risk for
flash flooding. Locations with greatest threats for flash flooding
include slot canyons, normally dry washes, slickrock areas,
recent burn scars, and urban areas.

While moisture availability will be plentiful, the one factor that
could impact afternoon convective development and evolution includes
the potential for nocturnal convection. If any nocturnal convection
occurs and skies remain sufficiently cloudy, we could see more
stable atmospheric conditions develop. This would inhibit the
development of convection into the afternoon, instead favoring a
more stratiform precip regime. Will be something to monitor as we
get closer.

In addition to widespread precipitation, this pattern will bring a
much-needed gradual cooling trend throughout the long term period.
Temperatures begin near-average on Sunday, dropping to around 5-10F
below seasonal averages by the end of the week.

&&

.AVIATION...KSLC...Moisture to continue to increase, corresponding
to increase in shower/thunderstorm chances, primarily from early
afternoon to evening. Convection will be capable of brief periods of
moderate to heavy rain, lightning, gusty erratic outflow winds, and
briefly reduced VIS/CIGS. Aside from precipitation, winds
anticipated to follow a typical diurnal pattern (shifting SSE ~03-
05Z Sat, back NW 17-19Z thereafter).

.REST OF UTAH AND SOUTHWEST WYOMING...A monsoonal moisture surge
will result in a more active period, especially at southern Utah
terminals. Shower/thunderstorm chances will be maximized early
afternoon through the evening, and bring a threat of moderate to
heavy rain, lightning, gusty erratic outflow winds, and briefly
reduced VIS/CIGS. Outside precipitation, winds are expected to
follow a largely typical diurnal pattern with magnitudes remaining
modest.

&&

.FIRE WEATHER...Moisture will continue to move into Utah from the
south, with another secondary surge arriving Sunday. Coverage of
showers and thunderstorms will continue to increase. Storms will
become wetter, with increasing chances for wetting rain and
decreasing chances for gusty outflow winds through at least
Wednesday. Relative humidity will also improve accordingly. One
area of forecast uncertainty is the amount of cloud cover, which
may limit the intensity of any developing storms and therefore
rainfall amounts, particularly after Sunday. Model guidance
currently suggests moisture will peak around Wednesday, with a
gradual decrease in moisture thereafter.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...Extreme Heat Warning until 9 PM MDT this evening for UTZ123-124.

WY...None.
&&

Cunningham/Whitlam/Warthen

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

The radar

The Salt Lake City radar (KMTX), 181 km away, was scanning. The volume nearest the first event began at 23:30 UTC.

Open the radar archive at this moment

Event by event

7 thunderstorm wind, 1 flash flood. Local standard time, as filed.

Thunderstorm Wind, Tooele

When
August 22, 4:30 PM MST
Where
Tooele County, 16.93 mi SSE of Gold Hill
Measured
61 kt (70 mph) measured gust
Reported by
Mesonet
Coordinates
39.946, -113.701

A wind gust of 70 mph was recorded at the Callao mesonet site.

Thunderstorm Wind, Tooele

When
August 24, 7:00 PM MST
Where
Tooele County, 16.68 mi SSE of Gold Hill
Measured
51 kt (59 mph) measured gust
Reported by
Mesonet
Coordinates
39.950, -113.700

A wind gust of 59 mph was recorded at the Callao mesonet site.

Thunderstorm Wind, Tooele

When
August 24, 7:10 PM MST
Where
Tooele County, 16.1 mi ESE of Gold Hill
Measured
76 kt (87 mph) measured gust
Reported by
Mesonet
Coordinates
40.117, -113.533

A wind gust of 87 mph was recorded at the Causeway mesonet site.

Flash Flood, Juab

When
August 24, 7:20 PM MST to 8:20 PM MST
Where
Juab County, 1.59 mi E of Nephi to 2.28 mi ESE of Nephi
Cause
Heavy Rain
Reported by
Newspaper
Coordinates
39.718, -111.800

Heavy rainfall from a thunderstorm falling over steep terrain in Nephi Canyon caused flooding and an associated closure of SR-132 at mile marker 35. A railroad weather station located near the top of the adjacent canyon recorded 0.59 inches of rain in 10 minutes and 0.9 inches of rain in 30 minutes. Time and location are estimated.

Thunderstorm Wind, Tooele

When
August 24, 7:50 PM MST
Where
Tooele County, 12.74 mi W of (Dpg)michael Aaf Dug
Measured
51 kt (59 mph) measured gust
Reported by
Mesonet
Coordinates
40.200, -113.170

A wind gust of 59 mph was recorded at the Horizontal Grid mesonet site.

Thunderstorm Wind, Tooele

When
August 24, 8:00 PM MST to 8:05 PM MST
Where
Tooele County, 11.09 mi SSW of (Dpg)michael Aaf Dug
Measured
56 kt (64 mph) measured gust
Reported by
Mesonet
Coordinates
40.046, -113.046

A wind gust of 65 mph was recorded at the Target S mesonet site.

Thunderstorm Wind, Tooele

When
August 24, 8:05 PM MST
Where
Tooele County, 9.63 mi WNW of (Dpg)michael Aaf Dug
Measured
55 kt (63 mph) measured gust
Reported by
Mesonet
Coordinates
40.242, -113.093

A wind gust of 63 mph was recorded at the Playa Station mesonet site.

Thunderstorm Wind, Tooele

When
August 24, 8:15 PM MST
Where
Tooele County, 18.02 mi S of (Dpg)michael Aaf Dug
Measured
54 kt (62 mph) measured gust
Reported by
Mesonet
Coordinates
39.919, -112.939

A wind gust of 62 mph was recorded at the Simpson Springs mesonet site.

What these are

Thunderstorm Wind
Winds from a thunderstorm of 50 knots (58 mph) or more, or lower winds that caused damage or casualties. Measured gusts are marked MG, estimated EG.
Flash Flood
Flooding that begins within six hours of the rain that causes it, or of a dam or levee failure or ice jam release, often with deadly speed.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

More

Every storm in Utah in 2025Every state in 2025This day in weather historyWarnings in Utah, August 2025

Sources

NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 1278629, 1278633, 1278635, 1278637, 1288902, 1278639, 1278644, 1278648.