Alert archive / Colorado / Severe Thunderstorm Warnings in 2025

Severe Thunderstorm Warning 335, NWS Denver/Boulder, CO

August 18, 2025Lincoln County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Aug 18, 2025, 3:50 PM MDT for Lincoln County, Colorado. It was in force for 40 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: Aug 18, 2025, 3:50 PM MDT (21:50 UTC)
Expired: Aug 18, 2025, 4:30 PM MDT
In force: 40 min
Issued by: NWS Denver/Boulder, CO
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

County Lincoln County, CO

The radar

The Pueblo radar (KPUX), 82 km from the middle of the area, began a volume at 21:52 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 nearest sounding before it

Dodge City, (KDDC), launched 12:00Z, 9.8 hours before the alert went out and 343 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 566 J/kg
Mixed-layer CIN: -303 J/kg
Mixed-layer LCL: 1798 m above ground
0-6 km bulk shear: 10 kt
0-1 km storm-relative helicity: 18 m²/s²
0-3 km storm-relative helicity: 90 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

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 Aug 18, 2:30 PM MDT, 1 hour 20 minutes earlier.

Area forecast discussion, Aug 18, 2:30 PM MDT, 1 hour 20 minutes before

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Hazardous weather outlook, Aug 18, 7:37 AM MDT, 8 hours 13 minutes before

Hazardous Weather Outlook
National Weather Service Denver/Boulder CO
737 AM MDT Mon Aug 18 2025

COZ030>051-191345-
Jackson County Below 9000 Feet-
West Jackson and West Grand Counties Above 9000 Feet-
Grand and Summit Counties Below 9000 Feet-
South and East Jackson/Larimer/North and Northeast Grand/
Northwest Boulder Counties Above 9000 Feet-
South and Southeast Grand/West Central and Southwest Boulder/
Gilpin/Clear Creek/Summit/North and West Park Counties Above
9000 Feet-Larimer and Boulder Counties Between 6000 and 9000 Feet-
Jefferson and West Douglas Counties Above 6000 Feet/Gilpin/Clear
Creek/Northeast Park Counties Below 9000 Feet-
Central and Southeast Park County-
Larimer County Below 6000 Feet/Northwest Weld County-
Boulder And Jefferson Counties Below 6000 Feet/West Broomfield
County-
North Douglas County Below 6000 Feet/Denver/West Adams and
Arapahoe Counties/East Broomfield County-
Elbert/Central and East Douglas Counties Above 6000 Feet-
Northeast Weld County-Central and South Weld County-Morgan County-
Central and East Adams and Arapahoe Counties-
North and Northeast Elbert County Below 6000 Feet/North Lincoln
County-
Southeast Elbert County Below 6000 Feet/South Lincoln County-
Logan County-Washington County-Sedgwick County-Phillips County-
737 AM MDT Mon Aug 18 2025

This hazardous weather outlook is for northeast and north central
Colorado.

.DAY ONE...Today and Tonight

SPC has upgraded our northeast plains to a slight risk (2 out of
5) for severe weather potential today. While the highest concern
is for these locations, there will still be a marginal threat
pushing as far west as the southern urban corridor and along the
Palmer Divide. Main hazards will be strong winds (up to 70 mph)
and large hail (between 1-2").

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday

Warmer and drier conditions will be in place through the work
week, with limited precipitation chances for Tuesday and
Wednesday. Moisture will start to increase by the end of the week
and cooler temperatures and increasing shower and storm coverage
is expected for the weekend.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed today or tonight, but any
and all severe reports are encouraged and appreciated!

In the hours before

Special weather statement, Aug 18, 2:21 PM MDT, 1 hour 29 minutes before

Special Weather Statement
National Weather Service Denver CO
221 PM MDT Mon Aug 18 2025

COZ040-041-045-182045-
North Douglas County Below 6000 Feet/Denver/West Adams and
Arapahoe Counties/East Broomfield County CO-Elbert/Central and
East Douglas Counties Above 6000 Feet CO-Central and East Adams
and Arapahoe Counties CO-
221 PM MDT Mon Aug 18 2025

...A STRONG THUNDERSTORM WILL IMPACT NORTHWESTERN ELBERT...CENTRAL
ARAPAHOE AND SOUTH CENTRAL ADAMS COUNTIES UNTIL 245 PM MDT...

At 221 PM MDT, Doppler radar was tracking a strong thunderstorm 6
miles south of Watkins, or 20 miles east of Denver, moving northeast
at 25 mph.

HAZARD...Wind gusts of 50 to 55 mph and half inch size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects. Minor damage to outdoor objects is possible.

Locations impacted include...
  Eastern Aurora, Bennett, Manila Village, Watkins, Arapahoe Park
  and Strasburg.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Monitor the weather situation closely and be alert for threatening
weather conditions.

Prepare for sudden gusty winds. Secure loose objects and move to a
safe shelter inside a building or vehicle.

&&

LAT...LON 3962 10469 3963 10472 3986 10460 3973 10428
      3954 10456
TIME...MOT...LOC 2020Z 211DEG 19KT 3966 10458

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...50 TO 55 MPH

Hiris

Special weather statement, Aug 18, 2:42 PM MDT, 1 hour 8 minutes before

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Special weather statement, Aug 18, 2:53 PM MDT, 57 minutes before

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Special weather statement, Aug 18, 3:22 PM MDT, 28 minutes before

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Special weather statement, Aug 18, 3:26 PM MDT, 24 minutes before

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Special weather statement, Aug 18, 3:34 PM MDT, 16 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
Aug 18, 1:04 PM MDT	Special Weather Statement	BOU	Washington	26 min
Aug 18, 1:46 PM MDT	Special Weather Statement	BOU	Douglas	29 min
Aug 18, 1:59 PM MDT	Special Weather Statement	BOU	Elbert	46 min
Aug 18, 2:09 PM MDT	Areal Flood Advisory	BOU	Elbert	3 hr
Aug 18, 2:16 PM MDT	Severe Thunderstorm Warning	BOU	Lincoln	29 min
Aug 18, 2:21 PM MDT	Special Weather Statement	BOU	Arapahoe	24 min
Aug 18, 2:42 PM MDT	Special Weather Statement	BOU	Lincoln	33 min
Aug 18, 2:50 PM MDT	Areal Flood Advisory	BOU	Elbert, Lincoln	3 hr
Aug 18, 2:53 PM MDT	Special Weather Statement	BOU	Adams	37 min
Aug 18, 3:02 PM MDT	Severe Thunderstorm Warning Considerable damage threat	BOU	Lincoln	28 min
Aug 18, 3:10 PM MDT	Severe Thunderstorm Warning	BOU	Adams, Arapahoe	24 min
Aug 18, 3:22 PM MDT	Special Weather Statement	BOU	Lincoln	38 min
Aug 18, 3:26 PM MDT	Special Weather Statement	BOU	Lincoln	49 min
Aug 18, 3:34 PM MDT	Special Weather Statement	BOU	Morgan	41 min
Aug 18, 3:38 PM MDT	Areal Flood Advisory	BOU	Elbert, Lincoln, Washington	3 hr
Aug 18, 3:54 PM MDT	Special Weather Statement	BOU	Morgan	36 min
Aug 18, 4:02 PM MDT	Special Weather Statement	BOU	Lincoln	58 min
Aug 18, 4:24 PM MDT	Special Weather Statement	BOU	Washington	51 min
Aug 18, 4:37 PM MDT	Special Weather Statement	BOU	Morgan	38 min
Aug 18, 5:05 PM MDT	Severe Thunderstorm Warning	BOU	Logan, Washington	40 min
Aug 18, 5:27 PM MDT	Special Weather Statement	BOU	Logan	48 min

Nearby

Severe Thunderstorm Warnings in Colorado, 2025 Every severe thunderstorm warning in 2025

Sources

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