A low pressure system and potent cold front moved through eastern Utah before lifting northeast across northwest Colorado, bringing widespread valley rain and mountain snow. Light to moderate snow accumulations favored the Eastern Uinta Mountains and La Sal Mountains in eastern Utah as well as the Park Range Mountains in northwest Colorado.
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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 GJT wrote it up.
A low pressure system and potent cold front moved through eastern Utah before lifting northeast across northwest Colorado, bringing widespread valley rain and mountain snow. Light to moderate snow accumulations favored the Eastern Uinta Mountains and La Sal Mountains in eastern Utah as well as the Park Range Mountains in northwest Colorado. Winds were strongest in eastern Utah with gusts above 45 mph.
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 Grand Junction, CO wrote its last area forecast discussion before the first event at May 17, 11:55 AM MST, 4 hours 5 minutes earlier. Its key messages:
Area Forecast Discussion
National Weather Service Grand Junction CO
1255 PM MDT Sun May 17 2026
.KEY MESSAGES...
- Showers and thunderstorms are expected today, with isolated
severe storms possible through the evening.
- Mountain snow returns tonight through tomorrow morning. A
Winter Weather Advisory has been issued for the eastern Uinta,
Elkhead, and Park Mountains.
- Freezing temperatures are expected to impact portions of the
region Monday night into Tuesday and again Tuesday night into
Wednesday. A Freeze Watch has been issued for the Central and
Lower Yampa River Basin for Monday night.
&&
.DISCUSSION...
Issued at 1243 PM MDT Sun May 17 2026
ISOLATED SEVERE STORMS TODAY:
Another round of showers and thunderstorms are expected through the
evening today while increased instability exists across the region.
The 18Z sounding from GJT shows an increase in low level moisture,
and an increase in PWATs, which should support more rain
actually reaching the ground when compared to yesterday
afternoon. Strong outflow winds, brief periods of heavy rain,
and small hail are the biggest concerns with today's storms.
WET THROUGH MONDAY:
A low pressure system moves across the CWA tonight, bringing a
transition from afternoon convection to more stratiform like
precipitation. This includes widespread rain and high elevation
snow. The center of the low, and greatest forcing, moves across
Utah late tonight, so precipitation rates are forecast to be the
greatest between midnight and noon tomorrow. Snow totals favor
the eastern Uinta mountains, where a Winter Weather Advisory is
in place above 8500 feet from 6 PM this evening through 6 PM
tomorrow. A Winter Weather Advisory is also in place for the
Elkhead and Park Mountains above 9500 feet from midnight tonight
to 9 PM tomorrow. By tomorrow afternoon the system will be east
of our area, however, lingering moisture could allow for some
light snowfall in the higher terrain though the day.
FREEZE POTENTIAL:
Cold air advection associated with the low pressure system moving
through the area tonight will significantly drop temperatures.
Tomorrow's high temperatures will be around 15 to 25 degrees
below normal. Tomorrow night's low temperatures will also be
well below normal for this time of the year. Freeze Watches are
in effect for late tomorrow night through Tuesday morning for
the Central and Lower Yampa River Basin. Temperatures will
gradually warm back to above normal by the weekend.
&&
.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 1153 AM MDT Sun May 17 2026
Showers and thunderstorms are developing across the region this
afternoon. The main threats with any showers or storms that
impact a terminal will be gusty and erratic winds, lightning,
and brief heavy rain. Heavy rain will supersede the gusty winds
after 00z as moisture increases. Convective showers and storms
will transition to more stratiform activity from north to south
starting after 03z. Higher elevation terminals, including KTEX,
could see snow mix in after 12z tomorrow morning as a cold front
moves through. Winds this afternoon will be southwesterly with
gusts of 25-35 knots expected, though higher gusts will be
possible with showers or storms. Winds will transition to
northerly to northwesterly tonight as the cold front moves
through, roughly accompanying the transition from convective to
stratiform precipitation. VFR conditions will prevail through
06z, then a mix of VFR and MVFR is expected as ceilings lower
and visibility is impacted by precipitation.
&&
.GJT WATCHES/WARNINGS/ADVISORIES...
CO...Freeze Watch from late Monday night through Tuesday morning
for COZ001-002.
Winter Weather Advisory from midnight tonight to 9 PM MDT
Monday for COZ004.
UT...Winter Weather Advisory from 6 PM this evening to 6 PM MDT
Monday for UTZ023.
&&
DISCUSSION...TGJT
AVIATION...TGJTSpecial Weather Statement
National Weather Service Grand Junction CO
209 PM MDT Sun May 17 2026
COZ002-005-013-172045-
Flat Tops CO-Upper Yampa River Basin CO-Central Yampa River Basin CO-
209 PM MDT Sun May 17 2026
...A STRONG THUNDERSTORM WILL IMPACT WEST CENTRAL ROUTT AND
SOUTHEASTERN MOFFAT COUNTIES THROUGH 245 PM MDT...
At 209 PM MDT, Doppler radar was tracking a strong thunderstorm 11
miles south of Craig, moving northeast at 30 mph.
HAZARD...Wind gusts of 50 to 55 mph and nickel size hail.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects. Minor hail damage to vegetation and
outdoor objects is possible.
Locations impacted include...
Craig, Hayden, and Hamilton.
This includes the following highways...
U.S. Highway 40 in Colorado between mile markers 93 and 111.
Colorado 13 between mile markers 74 and 79.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
&&
LAT...LON 4025 10756 4039 10767 4066 10733 4039 10710
TIME...MOT...LOC 2009Z 234DEG 27KT 4035 10755
MAX HAIL SIZE...0.88 IN
MAX WIND GUST...55 MPH
BWSpecial Weather Statement
National Weather Service Grand Junction CO
225 PM MDT Sun May 17 2026
COZ001>003-172100-
Roan and Tavaputs Plateaus CO-Lower Yampa River Basin CO-
Central Yampa River Basin CO-
225 PM MDT Sun May 17 2026
...A STRONG THUNDERSTORM WILL IMPACT NORTHWESTERN RIO BLANCO COUNTY
THROUGH 300 PM MDT...
At 225 PM MDT, Doppler radar was tracking a strong thunderstorm over
Rangely, or 49 miles southeast of Vernal, moving northeast at 45 mph.
HAZARD...Wind gusts up to 50 mph and half inch hail.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects. Minor hail damage to vegetation is
possible.
Locations impacted include...
Rangely and Massadona.
This includes the following highways...
U.S. Highway 40 in Colorado near mile marker 26.
Colorado 64 between mile markers 17 and 52.
Colorado 139 between mile markers 67 and 72.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
&&
LAT...LON 4001 10879 4013 10885 4034 10840 4008 10827
TIME...MOT...LOC 2025Z 244DEG 39KT 4006 10876
MAX HAIL SIZE...0.50 IN
MAX WIND GUST...50 MPH
BWPreliminary Local Storm Report
National Weather Service Grand Junction CO
258 PM MDT Sun May 17 2026
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0237 PM Non-Tstm Wnd Gst 3 NW Aspen 39.23N 106.87W
05/17/2026 M49 MPH Pitkin CO ASOS
&&Special Weather Statement
National Weather Service Grand Junction CO
259 PM MDT Sun May 17 2026
COZ004-005-172130-
Upper Yampa River Basin CO-Elkhead and Park Mountains CO-
259 PM MDT Sun May 17 2026
...STRONG THUNDERSTORMS WILL IMPACT NORTHEASTERN ROUTT COUNTY THROUGH
330 PM MDT...
At 257 PM MDT, Doppler radar was tracking strong thunderstorms over
mostly rural areas of Routt County. Movement was northeast at 45
mph.
HAZARD...Wind gusts of 50 to 55 mph and pea size hail.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects. Minor hail damage to vegetation is
possible.
Locations impacted include...
Steamboat Springs, Mt Zirkel, and Clark.
This includes the following highways...
U.S. Highway 40 in Colorado between mile markers 123 and 139.
Colorado 131 between mile markers 66 and 68.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
Frequent cloud to ground lightning is occurring with these storms.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.
&&
LAT...LON 4083 10666 4082 10664 4079 10664 4076 10667
4070 10667 4068 10669 4065 10668 4061 10670
4056 10669 4051 10665 4047 10667 4045 10665
4039 10665 4038 10690 4049 10701 4069 10707
4085 10666
TIME...MOT...LOC 2057Z 245DEG 40KT 4067 10703 4052 10698 4039 10690
MAX HAIL SIZE...0.25 IN
MAX WIND GUST...55 MPH
BWPreliminary Local Storm Report
National Weather Service Grand Junction CO
321 PM MDT Sun May 17 2026
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0230 PM Hail Hayden 40.49N 107.26W
05/17/2026 M1.25 Inch Routt CO Cocorahs
&&Special Weather Statement
National Weather Service Grand Junction CO
333 PM MDT Sun May 17 2026
COZ003-006-007-172200-
Roan and Tavaputs Plateaus CO-Debeque to Silt Corridor CO-
Grand Valley CO-
333 PM MDT Sun May 17 2026
...A STRONG THUNDERSTORM WILL IMPACT NORTHERN MESA AND SOUTH CENTRAL
GARFIELD COUNTIES THROUGH 400 PM MDT...
At 332 PM MDT, Doppler radar was tracking a strong thunderstorm 13
miles northeast of Fruita, or 13 miles north of Grand Junction,
moving east at 30 mph.
HAZARD...Wind gusts up to 50 mph and half inch hail.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects. Minor hail damage to vegetation is
possible.
This storm will remain over mainly rural areas of northern Mesa and
south central Garfield Counties.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.
&&
LAT...LON 3924 10859 3937 10857 3947 10825 3926 10828
TIME...MOT...LOC 2132Z 257DEG 28KT 3929 10854
MAX HAIL SIZE...0.50 IN
MAX WIND GUST...50 MPH
BWThe national radar mosaic for the moment the first event began.
1 winter weather. Local standard time, as filed.
Generally 3 to 8 inches of snow fell across the area with locally higher amounts up to 11 inches at Whiskey Park. Wind gusts peaked at 40 mph at Storm Peak Lab.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2026Every state in 2026This day in weather historyWarnings in Colorado, May 2026
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: 1336569.