Alert archive / Colorado / Severe Thunderstorm Warnings in 2026

Severe Thunderstorm Warning 55, NWS Denver/Boulder, CO

June 1, 2026Washington County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Jun 1, 2026, 5:45 PM MDT for Washington County, Colorado. It was in force for 15 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jun 1, 2026, 5:45 PM MDT (23:45 UTC)
Expired: Jun 1, 2026, 6:00 PM MDT
In force: 15 min
Issued by: NWS Denver/Boulder, CO
Area: Storm-based polygon
Hail: 1.25 in
Wind: 50.0 mph

County Washington County, CO

The radar

The Denver radar (KFTG), 117 km from the middle of the area, began a volume at 23:48 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.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Jun 1, 12:52 PM MDT	Severe Thunderstorm Watch	SPC	7 hr

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Denver/Boulder, CO wrote its last area forecast discussion before this severe thunderstorm warning went out at Jun 1, 2:05 PM MDT, 3 hours 40 minutes earlier. Its key messages:

A chance for strong and severe thunderstorms this afternoon along the I-25 Corridor, with large hail, gusty winds, and a brief tornado possible.
Severe storms will be possible again Tuesday afternoon, with locally heavy rain possible.
Thunderstorm chances will continue on Wednesday with lower threat for severe storms, however, locally heavy rain will be possible.
Trending warmer and drier by the end of the week.

Area forecast discussion, Jun 1, 2:05 PM MDT, 3 hours 40 minutes before

Area Forecast Discussion
National Weather Service Denver/Boulder CO
205 PM MDT Mon Jun 1 2026

.KEY MESSAGES...

- A chance for strong and severe thunderstorms this afternoon
  along the I-25 Corridor, with large hail, gusty winds, and a
  brief tornado possible.

- Severe storms will be possible again Tuesday afternoon, with
  locally heavy rain possible.

- Thunderstorm chances will continue on Wednesday with lower
  threat for severe storms, however, locally heavy rain will be
  possible.

- Trending warmer and drier by the end of the week.

&&

.DISCUSSION /Through Monday/...
Issued at 158 PM MDT Mon Jun 1 2026

The synoptic pattern shows a broad upper-level low is in place over
the Pacific Northwest, with a 80kt, southwest to northeast situated
upper-level jet residing across the Central Rockies on this Monday
morning. This is bringing southwesterly flow aloft across Colorado,
with fairly robust low-level moisture (50F dewpoints) advecting into
eastern Colorado via southeasterly upslope.

Latest East Meso-2 Day Cloud Phase shows cumulus clouds along the
Front Range Mountains are starting to show vertical growth early
this afternoon. These storms are expected to become more robust
within the next hour or two with potential for severe storms to
develop along the I-25 Corridor between the 1-2PM time frame, where
the SPC has the majority of our lower elevations in a Slight Risk
(2/5 threat level). Latest ACARS sounding shows MLCAPE values around
1000 J/kg, with only a few degrees of surface heating needed to
overcome a 700 mb inversion. Upslope flow to near 700 mb is also
visible on KFTG VAD Wind Profiler, with surface dewpoints ranging
from the upper-40s to mid-50s across the foothills and plains.
Expecting storms to initially be discrete in nature with large hail
(2-3") being the main threat, before progressing eastward where the
environment will be more conducive to a more linear storm mode, with
strong winds becoming the primary threat. While tornadoes are not
expected to be the main threat today, a brief tornado cannot be
ruled out where any low-level circulations can hold together. The
severe threat is expected to diminish from west to east, moving out
of metro Denver by 6PM and 8PM-9PM for the eastern plains. Hi-res
guidance has continued to show shower and non-severe thunderstorms
becoming reestablished behind the exiting severe threat, mainly
along the South Platte River Valley, by 11PM-12AM continuing to
around sunrise.

For Tuesday, flow aloft will transition to a more zonal pattern with
surface dewpoints expected to remain fairly robust once again.
MLCAPE values are not expected to be as strong as today, but values
between 500 to 1200 J/kg will be in place by the afternoon, with
conditions favorable for another day of severe storm potential
across the eastern plains. MUCAPE increasing to greater than 1500
J/kg mixed with steep mid-level lapse rates will support the
development of baseline severe hail size potential, with shear
weaker than today looking to keep the threat of anything larger than
2" limited and gusty outflows the most likely severe threat.
Expecting storms to initiate between 1PM to 3PM and coverage to be
far less than today, with the SPC having areas generally east of I-
25 in a Marginal risk (1/5 threat level).

Afternoon thunderstorms will be possible once again Wednesday, with
an isolated threat of some becoming severe, mainly for the eastern
plains. Temperatures are forecast to gradually increase through the
week, reaching for the 90s by Thursday as 700 mb flow warms by about
10C. Warmer and drier conditions are expected from Thursday onward,
with increasing elevated fire weather conditions expected as the
warmer and drier weather persists into the weekend, though with
greenup well underway and multiple chances for precip through
mid-week, any developing fire weather concerns will likely remain
limited and localized.

&&

.AVIATION /18Z TAFS through 18Z Tuesday/...
Issued at 1158 AM MDT Mon Jun 1 2026

East to southeast winds have increased moisture across the area
and brought stratocumulus clouds at 3,500 to 5,000 feet. These
clouds will burn off soon as the airmass warms.  This increase in
moisture will fuel thunderstorm development this afternoon
beginning around 19Z. Main time frame for a thunderstorm at DEN
will be 20Z to 23Z. Hail (possibly large), heavy rain, and wind
gusts to 50 knots will be possible under the stronger storms.
Models agree there should only be one round of thunderstorms this
afternoon, so by 22-00Z, expect storms to be east of DEN. 

Low clouds will develop after midnight between 08Z and 10Z and
then linger most of Tuesday morning. Ceilings are expected to be
in the 1000 to 3000 foot range, with a slight chance (20%) of
ceilings under 1,000 feet.  A Denver cyclone is expected to help
form the low clouds. Then mid morning winds become southeast. This
will end the threat of lower ceilings (~1000 feet) and slowly
erode the remaining low clouds. Another round of afternoon
thunderstorms is expected, beginning around 21Z. There's a chance
the airmass is capped, with the best chance for this occurring
north of Denver.  

&&

.BOU WATCHES/WARNINGS/ADVISORIES...
None.

&&

DISCUSSION...9
AVIATION...12

In the hours before

Local storm report, Jun 1, 4:06 PM MDT, 1 hour 39 minutes before

Preliminary Local Storm Report
National Weather Service Denver CO
406 PM MDT Mon Jun 1 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0338 PM     Hail             1 N Natural Fort        40.97N 104.92W
06/01/2026  E1.00 Inch       Weld               CO   Public

&&

Local storm report, Jun 1, 4:07 PM MDT, 1 hour 38 minutes before

Preliminary Local Storm Report
National Weather Service Denver CO
407 PM MDT Mon Jun 1 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0334 PM     Hail             3 NW Strasburg          39.77N 104.32W
06/01/2026  M1.50 Inch       Adams              CO   NWS Employee

0325 PM     Hail             1 S Parker              39.49N 104.76W
06/01/2026  M0.88 Inch       Douglas            CO   Trained Spotter

            Funnel cloud, too.

&&

Local storm report, Jun 1, 4:46 PM MDT, 59 minutes before

Preliminary Local Storm Report...Summary
National Weather Service Denver CO
446 PM MDT Mon Jun 1 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0439 PM     Hail             Simla                   39.14N 104.08W
06/01/2026  M1.25 Inch       Elbert             CO   Public

            Report from mPING: Half Dollar (1.25 in.).

0421 PM     Hail             6 E Woodrow             39.98N 103.46W
06/01/2026  M2.00 Inch       Washington         CO   Public

            Report from mPING: Hen Egg (2.00 in.).

0338 PM     Hail             1 N Natural Fort        40.97N 104.92W
06/01/2026  E1.00 Inch       Weld               CO   Public

0334 PM     Hail             3 NW Strasburg          39.77N 104.32W
06/01/2026  M1.50 Inch       Adams              CO   NWS Employee

0325 PM     Hail             1 S Parker              39.49N 104.76W
06/01/2026  M0.88 Inch       Douglas            CO   Trained Spotter

            Funnel cloud, too.

0312 PM     Hail             1 SE Bennett            39.74N 104.41W
06/01/2026  M1.75 Inch       Arapahoe           CO   Public

            Report from mPING: Golf Ball (1.75 in.).

0310 PM     Hail             1 SSE Bennett           39.74N 104.41W
06/01/2026  E2.00 Inch       Adams              CO   Trained Spotter

0308 PM     Hail             1 SE Bennett            39.74N 104.41W
06/01/2026  M1.50 Inch       Arapahoe           CO   Public

            Report from mPING: Ping Pong Ball (1.50
            in.).

0303 PM     Hail             3 W Bennett             39.76N 104.48W
06/01/2026  M1.75 Inch       Adams              CO   Broadcast Media

0302 PM     Hail             1 SW Bennett            39.74N 104.44W
06/01/2026  M1.25 Inch       Adams              CO   Public

            Report from mPING: Half Dollar (1.25 in.).

0248 PM     Hail             3 SE Manila Village     39.74N 104.47W
06/01/2026  M1.00 Inch       Adams              CO   Public

            Report from mPING: Quarter (1.00 in.).

0241 PM     Hail             1 SE Watkins            39.74N 104.59W
06/01/2026  M1.00 Inch       Adams              CO   Public

            Report from mPING: Quarter (1.00 in.).

0234 PM     Hail             4 E Buckley AFB         39.70N 104.67W
06/01/2026  M1.00 Inch       Arapahoe           CO   Broadcast Media

0232 PM     Hail             5 S Watkins             39.67N 104.60W
06/01/2026  M1.00 Inch       Arapahoe           CO   Public

            Report from mPING: Quarter (1.00 in.).

0205 PM     Hail             3 N Aurora              39.75N 104.82W
06/01/2026  M1.25 Inch       Adams              CO   Public

            Report from mPING: Half Dollar (1.25 in.).

0140 PM     Hail             3 W Aurora              39.72N 104.86W
06/01/2026  M1.00 Inch       Arapahoe           CO   Public

            Report from mPING: Quarter (1.00 in.).

0135 PM     Funnel Cloud     1 W Kassler             39.49N 105.11W
06/01/2026                   Jefferson          CO   Public

0135 PM     Funnel Cloud     3 W Castle Pines        39.49N 104.93W
06/01/2026                   Douglas            CO   Trained Spotter

            The funnel dropped from the south west edge
            of the storm. Was clean and wide for about 5
            minutes, then became ropy before
            disappearing.

0134 PM     Funnel Cloud     1 S Chatfield Reservoir 39.54N 105.06W
06/01/2026                   Douglas            CO   Public

0134 PM     Hail             6 E Greenland           39.16N 104.75W
06/01/2026  M1.25 Inch       Douglas            CO   Public

            Report from mPING: Half Dollar (1.25 in.).

0133 PM     Hail             2 NW Denver             39.76N 105.02W
06/01/2026  M1.00 Inch       Denver             CO   Public

            Report from mPING: Quarter (1.00 in.).

0131 PM     Hail             2 SE Chatfield Reservoi 39.54N 105.03W
06/01/2026  E1.50 Inch       Douglas            CO   Public

0130 PM     Hail             4 E Denver              39.75N 104.91W
06/01/2026  M0.88 Inch       Denver             CO   Trained Spotter

0128 PM     Hail             2 E Denver              39.74N 104.95W
06/01/2026  E1.25 Inch       Denver             CO   Trained Spotter

            Report from mPING: Half Dollar (1.25 in.).

0123 PM     Hail             3 E Denver              39.74N 104.92W
06/01/2026  M1.00 Inch       Denver             CO   Public

            Report from mPING: Quarter (1.00 in.).

0122 PM     Hail             4 E Denver              39.75N 104.92W
06/01/2026  M1.75 Inch       Denver             CO   Trained Spotter

0119 PM     Hail             3 E Denver              39.74N 104.92W
06/01/2026  M1.00 Inch       Denver             CO   Public

            Report from mPING: Quarter (1.00 in.).

0115 PM     Hail             1 SE Denver             39.73N 104.98W
06/01/2026  M1.00 Inch       Denver             CO   Public

            Most hail was smaller.

0114 PM     Hail             1 SE Denver             39.73N 104.97W
06/01/2026  M1.50 Inch       Denver             CO   Trained Spotter

0111 PM     Hail             1 SE Denver             39.73N 104.98W
06/01/2026  E1.00 Inch       Denver             CO   Public

            Report from mPING: Quarter (1.00 in.).

0110 PM     Hail             2 W Denver              39.74N 105.02W
06/01/2026  M1.00 Inch       Denver             CO   Trained Spotter

0110 PM     Hail             1 NW Denver             39.75N 105.00W
06/01/2026  E1.75 Inch       Denver             CO   Public

0107 PM     Hail             Denver                  39.74N 104.99W
06/01/2026  M1.00 Inch       Denver             CO   NWS Employee

0105 PM     Hail             1 E Edgewater           39.75N 105.04W
06/01/2026  M1.00 Inch       Denver             CO   Trained Spotter

&&

Local storm report, Jun 1, 4:59 PM MDT, 46 minutes before

Preliminary Local Storm Report
National Weather Service Denver CO
459 PM MDT Mon Jun 1 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0454 PM     Hail             3 E Elizabeth           39.37N 104.55W
06/01/2026  E1.00 Inch       Elbert             CO   Public

            Report from mPING: Quarter (1.00 in.).

&&

Local storm report, Jun 1, 5:11 PM MDT, 34 minutes before

Preliminary Local Storm Report
National Weather Service Denver CO
511 PM MDT Mon Jun 1 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0456 PM     Hail             2 W Matheson            39.17N 104.01W
06/01/2026  M1.50 Inch       Elbert             CO   Trained Spotter

&&

Local storm report, Jun 1, 5:43 PM MDT, 2 minutes before

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The office that day

Everything else NWS Denver/Boulder, CO issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 1, 5:41 AM MDT	Special Weather Statement	BOU	Washington	34 min
Jun 1, 6:38 AM MDT	Special Weather Statement	BOU	Washington	37 min
Jun 1, 8:22 AM MDT	Special Weather Statement	BOU	Logan	38 min
Jun 1, 8:58 AM MDT	Special Weather Statement	BOU	Logan	47 min
Jun 1, 1:04 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Arapahoe, Denver	41 min
Jun 1, 1:28 PM MDT	Severe Thunderstorm Warning	BOU	Arapahoe, Denver, Douglas	47 min
Jun 1, 1:31 PM MDT	Severe Thunderstorm Warning	BOU	Douglas, Elbert	44 min
Jun 1, 1:35 PM MDT	Severe Thunderstorm Warning	BOU	Boulder, Weld	23 min
Jun 1, 1:38 PM MDT	Severe Thunderstorm Warning Considerable damage threat	BOU	Adams, Arapahoe, Denver	52 min
Jun 1, 1:53 PM MDT	Severe Thunderstorm Warning	BOU	Arapahoe	37 min
Jun 1, 2:04 PM MDT	Areal Flood Advisory	BOU	Adams, Arapahoe, Denver	3 hr
Jun 1, 2:14 PM MDT	Flash Flood Warning	BOU	Adams, Arapahoe, Denver	95 min
Jun 1, 2:21 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Arapahoe, Denver	39 min
Jun 1, 2:29 PM MDT	Tornado Warning	BOU	Adams, Arapahoe	46 min
Jun 1, 2:52 PM MDT	Severe Thunderstorm Warning Considerable damage threat	BOU	Adams, Arapahoe	53 min
Jun 1, 3:02 PM MDT	Tornado Warning	BOU	Adams, Arapahoe	43 min
Jun 1, 3:07 PM MDT	Severe Thunderstorm Warning Considerable damage threat	BOU	Larimer, Weld	38 min
Jun 1, 3:13 PM MDT	Severe Thunderstorm Warning Considerable damage threat	BOU	Adams, Arapahoe, Washington	47 min
Jun 1, 3:24 PM MDT	Tornado Warning	BOU	Adams, Washington	39 min
Jun 1, 3:28 PM MDT	Severe Thunderstorm Warning Considerable damage threat	BOU	Larimer, Weld	18 min
Jun 1, 3:33 PM MDT	Severe Thunderstorm Warning	BOU	Arapahoe, Douglas, Elbert	25 min
Jun 1, 3:34 PM MDT	Severe Thunderstorm Warning Considerable damage threat	BOU	Adams, Weld	41 min
Jun 1, 3:40 PM MDT	Severe Thunderstorm Warning Considerable damage threat	BOU	Adams, Morgan, Washington	50 min
Jun 1, 3:53 PM MDT	Severe Thunderstorm Warning Considerable damage threat	BOU	Adams, Morgan, Weld	25 min
Jun 1, 4:24 PM MDT	Severe Thunderstorm Warning Considerable damage threat	BOU	Morgan, Washington	41 min
Jun 1, 4:37 PM MDT	Severe Thunderstorm Warning Considerable damage threat	BOU	Morgan, Washington	28 min
Jun 1, 4:38 PM MDT	Severe Thunderstorm Warning	BOU	Douglas, Elbert	52 min
Jun 1, 4:51 PM MDT	Severe Thunderstorm Warning	BOU	Elbert	39 min
Jun 1, 5:00 PM MDT	Tornado Warning	BOU	Washington	45 min
Jun 1, 5:04 PM MDT	Severe Thunderstorm Warning	BOU	Logan, Washington	41 min
Jun 1, 5:07 PM MDT	Severe Thunderstorm Warning	BOU	Elbert	23 min
Jun 1, 5:26 PM MDT	Severe Thunderstorm Warning	BOU	Washington	34 min
Jun 1, 5:28 PM MDT	Tornado Warning	BOU	Washington	32 min
Jun 1, 5:53 PM MDT	Special Weather Statement	BOU	Logan, Phillips, Sedgwick	67 min

Nearby

Severe Thunderstorm Warnings in Colorado, 2026 Every severe thunderstorm warning in 2026

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; radar from the NEXRAD Level II archive.