A broad cutoff low transited the Great Basin region in early May, resulting in isolated strong wind gusts and flash flooding.
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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.
The episode as NWS SLC wrote it up.
A broad cutoff low transited the Great Basin region in early May, resulting in isolated strong wind gusts and flash flooding.
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 May 3, 2:23 PM MST, 3 hours 22 minutes earlier.
Area Forecast Discussion
National Weather Service Salt Lake City UT
323 PM MDT Sat May 3 2025
.SYNOPSIS...A transition to cooler and wetter weather will spread
across Utah and southwest Wyoming over the next 24-36 hours as a
late season cold storm progresses into the region. This system
departs the region by the middle of next week, with warmer and
drier weather expected through the second half of the week.
&&
.DISCUSSION...A cold, late season winter-like storm system will
begin moving into the southwestern U.S. over the next 12-18 hours,
brining a variety of impacts across the forecast area. This storm
system is anticipated to bring precipitation throughout the region
from Sunday through at least Tuesday morning. Some key points to
note during this storm system are:
* Significant accumulations of high elevation (9,000+ft) snowfall
are expected across the southern Utah mountains. Anyone with
plans to recreate in the southern mountains on Sunday through at
least Tuesday should expect significant late season snowfall.
* Minor impacts to travel should be anticipated over the high
elevation pass on SR-12 near Boulder Mountain during the
overnight hours on Sunday night into Monday, and again on Monday
night into Tuesday.
* Temperatures will become much colder by Monday as a cooler
airmass settles into the region. Southern Utah will see the most
drastic change as high temperatures become upwards of 20
degrees below normal in Cedar City and St. George.
As noted, primary impacts from snowfall with this upcoming storm
will be limited to the highest terrain across Utah's mountains.
The decision was made to issue a Winter Weather Advisory for the
southern mountains for elevations above 9,000ft MSL as there is a
significant lack of snowpack which may encourage increased outdoor
recreation in these areas. Slightly lower accumulations, but still
upwards of 10 inches, are expected in the higher terrain
(10,000+ft) of the western Uinta Mountains, however, outdoor
recreationalists are likely to expect a deeper snowpack in this
region. Additionally, seasonal roadways (i.e. Bald Mountain Pass)
remain closed at this time... so no impacts to travel are
expected. That said, anyone with plans to get out in the mountains
from Sunday through Tuesday should expect periods of moderate to
heavy snowfall above 10,000ft.
For the valley areas and lower elevation mountains, rainfall will
be primarily maximized from southwest Utah, with a secondary
maxima expected northeastward through the Wasatch Back/ Uinta
Basin. In southern Utah, rainfall will vary between 0.5 inches and
1.5 inches, with high uncertainty over the mountainous terrain
(upwards of 1.5-2 inches of spread between the 25th to 75th
percentile). The uncertainty in accumulated precipitation will
also extend through the remainder of Utah's mountains. Any areas
experiencing prolonged moderate to heavy rainfall are likely to
see rises on area creeks and streams, though flood impacts are not
anticipated at this time.
The center of the low associated with this system will depart the
region from Tuesday through early Wednesday. In the wake of the
trough/ low, moisture will linger in the lower levels while broad
ridging and weak surface high pressure builds into the eastern
Great Basin region. As a result, we'll see anywhere from a 20-40%
chance of isolated shower and thunderstorm development over the
high terrain across Utah through much of the upcoming week. Under
the influence of this broad ridge, surface temperatures will make
a strong rebound to above normal levels by Friday.
There is indication that a weak shortwave trough will attempt to
progress through the ridge late in the week/ over the weekend. The
biggest influence of this would bring an increased coverage of
showers and thunderstorms across the region. Otherwise, there is
virtually no impactful weather forecast at this time from
Wednesday forward.
&&
.AVIATION...KSLC...Light northwest winds will prevail through around
03Z when winds transition to southeast. Clouds will increase into
the evening, with scattered to broken clouds in VFR range by around
03Z. Scattered rain showers and thunderstorms from around 19-03Z
will be capable of gusty, erratic outflow winds.
.REST OF UTAH AND SOUTHWEST WYOMING...Dry, mostly clear conditions
will last through the day for southwest Wyoming and northern Utah.
Scattered rain showers and thunderstorms for southern Utah through
around 03Z will be capable of gusty, erratic outflow winds.
Thunderstorms will diminish, but showers will last through the
night. Broken to overcast conditions in VFR range will prevail.
Clouds will increase northward, with scattered to broken clouds in
VFR range for southwest Wyoming and northern Utah by around 03Z.
Scattered showers and thunderstorms are likely throughout from
around 19-03Z.
&&
.SLC WATCHES/WARNINGS/ADVISORIES...
UT...Winter Weather Advisory from 6 AM Sunday to 6 AM MDT Tuesday for
UTZ125.
WY...None.
&&
DISCUSSION...Webber
AVIATION...Wilson
For more information from NOAA's National Weather Service visit...
http://weather.gov/saltlakecityThe Cedar City radar (KICX), 64 km away, was scanning. The volume nearest the first event began at 00:44 UTC.
5 thunderstorm wind, 1 flash flood. Local standard time, as filed.
The Bryce Canyon Airport ASOS (KBCE) recorded a wind gust of 59 mph as a result of outflow winds associated with a nearby cluster of showers and thunderstorms moving through the area.
The Mineral Mountains mesonet station recorded a wind gust of 60 mph as a result of outflow winds associated with a nearby cluster of showers and thunderstorms moving through the area.
The FISH SPRINGS mesonet station recorded a wind gust of 61 mph as a result of outflow winds associated with a nearby cluster of showers and thunderstorms moving through the area.
The Cat Claw Canyon flood/river gauge reported a rapid rise from a no-flow 0 CFS state to a peak flow of 620 CFS. Flash flood area extrapolated downstream to account for likely continued propagation of flood wave.
The BULLFROG BASIN MARINA mesonet station recorded a wind gust of 59 mph as a result of outflow winds associated with a nearby cluster of showers and thunderstorms moving through the area.
The I-80 at MP 79 Timpie mesonet station recorded a wind gust of 59 mph as a result of outflow winds associated with a nearby cluster of showers and thunderstorms moving through the area.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Utah in 2025Every state in 2025This day in weather historyWarnings in Utah, May 2025
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: 1246979, 1246980, 1246984, 1246986, 1246982, 1246983.