Alert archive / Colorado / Tornado Warnings in 2026

Tornado Warning 3, NWS Denver/Boulder, CO

May 21, 2026Washington County, Colorado

NWS Denver/Boulder, CO issued this tornado warning at May 21, 2026, 5:56 PM MDT for Washington County, Colorado. It was in force for 36 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: May 21, 2026, 5:56 PM MDT (23:56 UTC)
Expired: May 21, 2026, 6:32 PM MDT
In force: 36 min
Issued by: NWS Denver/Boulder, CO
Area: Storm-based polygon
Tornado: Radar indicated
Hail: 2.5 in

County Washington County, CO

The radar

The Goodland radar (KGLD), 107 km from the middle of the area, began a volume at 23:55 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.

Did it verify

Not verified. The Iowa Environmental Mesonet's Cow found no qualifying storm report inside this tornado warning while it was in force. That is not proof nothing happened: reports are thin where few people live.

Cow counts a report within 15 km of the polygon while the warning was in force: a tornado for a tornado warning; hail of 1 inch or more, a gust of 58 mph or more or wind damage for a severe thunderstorm warning; a flash flood report for a flash flood warning.

The watch it was issued in

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

Issued	Product	Office	Lasted
May 21, 2:55 PM MDT	Severe Thunderstorm Watch	SPC	7 hr

The text

As transmitted.

964 
WFUS55 KBOU 212356
TORBOU
COC121-220045-
/O.NEW.KBOU.TO.W.0003.260521T2356Z-260522T0045Z/

BULLETIN - EAS ACTIVATION REQUESTED
Tornado Warning
National Weather Service Denver CO
556 PM MDT Thu May 21 2026

The National Weather Service in Denver has issued a

* Tornado Warning for...
  Southeastern Washington County in northeastern Colorado...

* Until 645 PM MDT.

* At 556 PM MDT, a severe thunderstorm capable of producing a tornado
  was located near Cope, or 40 miles southeast of Akron, moving east
  at 15 mph.

  HAZARD...Tornado and tennis ball size hail.

  SOURCE...Radar indicated rotation.

  IMPACT...Flying debris will be dangerous to those caught without
           shelter. Mobile homes will be damaged or destroyed. Damage
           to roofs, windows and vehicles will occur. Tree damage is
           likely.

* Locations impacted include...
  Cope.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to an interior room on the lowest floor of a well-built building
away from windows. If you are outdoors, in a mobile home, or in a
vehicle, move to the closest substantial shelter and protect yourself
from flying debris.

&&

LAT...LON 3958 10294 3977 10294 3979 10280 3958 10280
TIME...MOT...LOC 2355Z 254DEG 15KT 3964 10289

TORNADO...RADAR INDICATED
MAX HAIL SIZE...2.50 IN

$$

63

3 follow-up statements

122 
WWUS55 KBOU 220006
SVSBOU

Severe Weather Statement
National Weather Service Denver CO
606 PM MDT Thu May 21 2026

COC121-220045-
/O.CON.KBOU.TO.W.0003.000000T0000Z-260522T0045Z/
Washington CO-
606 PM MDT Thu May 21 2026

...TORNADO WARNING REMAINS IN EFFECT UNTIL 645 PM MDT FOR
SOUTHEASTERN WASHINGTON COUNTY...

At 606 PM MDT, a severe thunderstorm capable of producing a tornado
was located over Cope, or 38 miles southeast of Akron, moving
northeast at 25 mph.

HAZARD...Tornado and tennis ball size hail.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without
         shelter. Mobile homes will be damaged or destroyed. Damage
         to roofs, windows and vehicles will occur. Tree damage is
         likely.

Locations impacted include...
  Cope.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to an interior room on the lowest floor of a well-built building
away from windows. If you are outdoors, in a mobile home, or in a
vehicle, move to the closest substantial shelter and protect yourself
from flying debris.

&&

LAT...LON 3958 10294 3977 10294 3979 10280 3958 10280
TIME...MOT...LOC 2356Z 216DEG 20KT 3964 10288

TORNADO...RADAR INDICATED
MAX HAIL SIZE...2.50 IN

$$

63

276 
WWUS55 KBOU 220023
SVSBOU

Severe Weather Statement
National Weather Service Denver CO
623 PM MDT Thu May 21 2026

COC121-220045-
/O.CON.KBOU.TO.W.0003.000000T0000Z-260522T0045Z/
Washington CO-
623 PM MDT Thu May 21 2026

...TORNADO WARNING REMAINS IN EFFECT UNTIL 645 PM MDT FOR
SOUTHEASTERN WASHINGTON COUNTY...

At 623 PM MDT, a severe thunderstorm capable of producing a tornado
was located 8 miles southwest of Cope, or 42 miles south of Akron,
moving east at 15 mph.

HAZARD...Tornado and two inch hail.

SOURCE...Radar indicated rotation.

IMPACT...Flying debris will be dangerous to those caught without
         shelter. Mobile homes will be damaged or destroyed. Damage
         to roofs, windows and vehicles will occur. Tree damage is
         likely.

Locations impacted include...
  Cope.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to an interior room on the lowest floor of a well-built building
away from windows. If you are outdoors, in a mobile home, or in a
vehicle, move to the closest substantial shelter and protect yourself
from flying debris.

&&

LAT...LON 3958 10294 3968 10294 3968 10281 3961 10280
      3958 10280
TIME...MOT...LOC 0006Z 269DEG 13KT 3959 10302

TORNADO...RADAR INDICATED
MAX HAIL SIZE...2.00 IN

$$

63

064 
WWUS55 KBOU 220032
SVSBOU

Severe Weather Statement
National Weather Service Denver CO
632 PM MDT Thu May 21 2026

COC121-220042-
/O.CAN.KBOU.TO.W.0003.000000T0000Z-260522T0045Z/
Washington CO-
632 PM MDT Thu May 21 2026

...TORNADO WARNING IS CANCELLED FOR SOUTHEASTERN WASHINGTON COUNTY...

The tornado threat has diminished and the Tornado Warning has been
cancelled. However, large hail and damaging winds remain likely and a
Severe Thunderstorm Warning remains in effect for the area.

A Severe Thunderstorm Watch remains in effect until 1000 PM MDT
Thursday for a portion of northeast Colorado.

&&

LAT...LON 3958 10294 3968 10294 3968 10281 3961 10280
      3958 10280
TIME...MOT...LOC 0023Z 269DEG 13KT 3959 10294

$$

63

What forecasters said that day

The local office's own words before this tornado 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 tornado warning went out at May 21, 1:03 PM MDT, 4 hours 53 minutes earlier. Its key messages:

Strong to locally severe thunderstorms expected late this afternoon through this evening in the plains, mainly east of I-25.
Elsewhere, weaker isolated to scattered showers/t-storms can be expected with and behind an early evening cold front.
Lingering showers into Friday, mainly south of I-70. Remaining cool.
Warmer and drier this weekend, with isolated showers possible Saturday afternoon.
Remaining mild next week but with a return of potential afternoon showers and thunderstorms.

Area forecast discussion, May 21, 1:03 PM MDT, 4 hours 53 minutes before

Area Forecast Discussion
National Weather Service Denver/Boulder CO
103 PM MDT Thu May 21 2026

.KEY MESSAGES...

- Strong to locally severe thunderstorms expected late this
  afternoon through this evening in the plains, mainly east of
  I-25.

- Elsewhere, weaker isolated to scattered showers/t-storms can be
  expected with and behind an early evening cold front.

- Lingering showers into Friday, mainly south of I-70. Remaining
  cool.

- Warmer and drier this weekend, with isolated showers possible
  Saturday afternoon.

- Remaining mild next week but with a return of potential
  afternoon showers and thunderstorms.

&&

.DISCUSSION /Through Thursday/...
Issued at 1218 PM MDT Thu May 21 2026

Ingredients are coming together as anticipated to provide for an
active afternoon and evening for our plains in particular. Cloud
cover has reduced considerably across the urban corridor and will
continue to thin over the plains in the coming hours, helping to
destabilize the environment. Surface moisture remains a potential
limiting factor for portions of the I-25 corridor with dewpoints
falling below 40F this afternoon, capping MLCAPE below ~400 J/Kg
at most.

Thunderstorms remain on track to develop mid-afternoon, mainly
after 3-4pm, favoring initiation east of I-25 and off the Palmer
Divide, where a DCVZ will become increasingly pronounced as the
afternoon progresses. These will spread into a much more unstable
environment in the eastern plains where an axis of more favorable
low-level moisture (dewpoints exceeding 50F) is present, roughly
to the east of the north/south line from Fort Morgan to Agate.
Ample bulk shear of 45-60 kts should support sustained growth of a
few supercells into Lincoln/Washington/Logan Counties late
afternoon into early evening, capable of producing large hail to
~2" in diameter with the strongest storms, as well as isolated
strong wind gusts and/or a weak tornado.

For the urban corridor, the highest chances for showers and
thunderstorms will arrive in the evening as a cold front descends
south between 5-8pm, although any convection should be sub-severe.
However, the front will provide an opportunity for redevelopment
of strong thunderstorms into the plains, reinforced by a secondary
frontal surge mid/late evening associated with the upper level
trough axis. With time, convection should become less discrete in
nature, favoring some upscale growth into a broader area of
thunderstorms across the northeast plains, exiting into KS/NE
roughly after midnight. Post-frontal winds will remain robust
overnight across our plains with gusts 25-40 mph.

This evening's front will usher in cooler temperatures for Friday,
along with a more stable airmass that will significantly reduce
precipitation potential for most areas. Nonetheless, some pockets
of marginal instability could remain south of I-70, and upslope
flow combined with the passage of another (weaker) shortwave aloft
will promote some showers and potentially a few weak thunderstorms
in the late afternoon and evening, focused across the Palmer
Divide.

We'll trend noticeably warmer Saturday into Sunday, with the
latter seeing highs climb into the lower 80's for the plains and
urban corridor. Some lingering mid-level moisture and yet another
weak shortwave may support isolated and weak high-based convection
on Saturday, although most will stay dry, and that will certainly
be the case on Sunday as higher pressure settles in. A more
unsettled pattern looks to return as early as Monday with renewed
potential for diurnal showers and thunderstorms through much of
the week.

&&

.AVIATION /18Z TAFS through 18Z Friday/...
Issued at 1151 AM MDT Thu May 21 2026

VFR conditions expected through the TAF period. Winds are
currently light and VRB at all TAF sites and will continue for the
next hour or two. By 20Z, winds should become more easterly
(easterly to southeasterly and DEN) around 10-15 kts.
Precipitation chances increases at this time, however convection
should be isolated-to-scattered through 00Z and may not impact the
airports besides gusty outflows. For this reason, have decided to
keep the PROB30 for all terminals. Between 00Z and 05Z convection
should increase with the arrival of the cold front, however
the bulk of the precipitation looks to stay east of the airports.
Have decided to keep the PROB30 in the TAF instead of TEMPO due to
this uncertainty. However, gusty VRB outflow winds are still
possible.

With the arrival of the cold front (around 01Z/02Z), expect
northerly winds gusting up to 30 kts, before gradually weakening
and turning more easterly by 05Z and through the morning. There is
a low chance (<30% chance) that ceilings could drop down to MVFR
conditions (between 2500 and 3000 ft) behind that front. However,
expect lifting between 05Z-08Z.

&&

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

&&

DISCUSSION...BRQ
AVIATION...MAI

In the hours before

Local storm report, May 21, 5:11 PM MDT, 45 minutes before

Preliminary Local Storm Report
National Weather Service Denver CO
511 PM MDT Thu May 21 2026

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

0450 PM     Hail             5 S Last Chance         39.65N 103.59W
05/21/2026  E1.00 Inch       Washington         CO   Storm Chaser

            Report from mPING: Quarter (1.00 in.).

&&

Local storm report, May 21, 5:19 PM MDT, 37 minutes before

Preliminary Local Storm Report
National Weather Service Denver CO
519 PM MDT Thu May 21 2026

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

0506 PM     Hail             5 SSE Last Chance       39.67N 103.53W
05/21/2026  M2.50 Inch       Washington         CO   Trained Spotter

&&

Local storm report, May 21, 5:23 PM MDT, 33 minutes before

Preliminary Local Storm Report
National Weather Service Denver CO
523 PM MDT Thu May 21 2026

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

0519 PM     Hail             6 S Lindon              39.64N 103.41W
05/21/2026  M2.50 Inch       Washington         CO   Storm Chaser

            Report from mPING: Tennis Ball (2.50 in.).

&&

Local storm report, May 21, 5:46 PM MDT, 10 minutes before

Preliminary Local Storm Report
National Weather Service Denver CO
546 PM MDT Thu May 21 2026

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

0535 PM     Tornado          3 WNW Thurman           39.61N 103.27W
05/21/2026                   Washington         CO   Trained Spotter

            Brief ground circulation. Report via
            NWSChat.

&&

Local storm report, May 21, 5:48 PM MDT, 8 minutes before

Preliminary Local Storm Report
National Weather Service Denver CO
548 PM MDT Thu May 21 2026

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

0544 PM     Hail             2 WNW Thurman           39.61N 103.24W
05/21/2026  M2.75 Inch       Washington         CO   Trained Spotter

&&

Local storm report, May 21, 5:56 PM MDT, 0 minutes before

Preliminary Local Storm Report
National Weather Service Denver CO
556 PM MDT Thu May 21 2026

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

0547 PM     Hail             1 S Thurman             39.58N 103.22W
05/21/2026  E3.00 Inch       Washington         CO   Trained Spotter

            Report from mPING: Tea Cup (3.00 in.).

&&

The office that day

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

Issued	Product	Office	Counties	Lasted
May 21, 2:53 PM MDT	Special Weather Statement	BOU	Arapahoe	37 min
May 21, 3:30 PM MDT	Severe Thunderstorm Warning	BOU	Arapahoe	30 min
May 21, 3:57 PM MDT	Severe Thunderstorm Warning	BOU	Logan	33 min
May 21, 4:30 PM MDT	Severe Thunderstorm Warning	BOU	Logan	30 min
May 21, 4:33 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Arapahoe, Washington	42 min
May 21, 4:52 PM MDT	Tornado Warning	BOU	Lincoln, Washington	38 min
May 21, 5:22 PM MDT	Tornado Warning	BOU	Lincoln, Washington	38 min
May 21, 5:32 PM MDT	Severe Thunderstorm Warning	BOU	Logan	43 min
May 21, 5:59 PM MDT	Tornado Warning	BOU	Washington	31 min

Nearby

Tornado Warnings in Colorado, 2026 Every tornado warning in 2026 Tornadoes 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.