Alert archive / Colorado / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 329, NWS Denver/Boulder, CO

July 20, 2023Lincoln County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Jul 20, 2023, 6:22 PM MDT for Lincoln County, Colorado. It was in force for 38 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
Jul 20, 2023, 6:22 PM MDT (00:22 UTC)
Expired
Jul 20, 2023, 7:00 PM MDT
In force
38 min
Issued by
NWS Denver/Boulder, CO
Area
Storm-based polygon
Hail
1.25 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 00:25 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.

IssuedProductOfficeLasted
Jul 20, 1:27 PM MDTSevere Thunderstorm WatchSPC9 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 Jul 20, 5:39 PM MDT, 43 minutes earlier.

Area forecast discussion, Jul 20, 5:39 PM MDT, 43 minutes before
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Hazardous weather outlook, Jul 20, 10:13 AM MDT, 8 hours 9 minutes before
Hazardous Weather Outlook
National Weather Service Denver/Boulder CO
1013 AM MDT Thu Jul 20 2023

COZ030>051-211615-
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-
1013 AM MDT Thu Jul 20 2023

...Strong to severe thunderstorms possible through this evening...

...Flood Watch in effect for eastern Elbert, Lincoln and Washington
counties 2 PM to 10 PM this evening...

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

.DAY ONE...Today and Tonight

An active period of thunderstorms will occur through this
evening with storms becoming stronger and more numerous during
the afternoon and evening hours. Some of these storms are expected
to become severe across the plains with hail up to tennis ball
size, damaging wind gusts, very heavy rain, and isolated
tornadoes.

The flash flood threat will be elevated in the burn scars this
afternoon, with the greatest threat of flash flooding expected to
be over Lincoln, Eastern Elbert and Washington counties.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

Thunderstorm activity will decrease Friday with isolated to
scattered thunderstorms. By Saturday, most areas will be dry with
only a few high based showers and storms possible over the
higher terrain. Temperatures will be increasing with highs
reaching the mid 90s Sunday and into early next week.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will be needed across the plains through this
evening.

In the hours before

Local storm report, Jul 20, 3:49 PM MDT, 2 hours 33 minutes before
Preliminary Local Storm Report...Summary
National Weather Service Denver CO
349 PM MDT Thu Jul 20 2023

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

0343 PM     Hail             Simla                   39.15N 104.08W
07/20/2023  E1.75 inch       Elbert             CO   Trained Spotter

0250 PM     Hail             4 E Kiowa               39.33N 104.38W
07/20/2023  M1.75 inch       Elbert             CO   Trained Spotter

0213 PM     Hail             4 ENE Ponderosa Park    39.41N 104.57W
07/20/2023  M1.00 inch       Elbert             CO   Trained Spotter

            Spotter: E561.

0208 PM     Hail             1 NE Ponderosa Park     39.41N 104.62W
07/20/2023  E1.00 inch       Elbert             CO   Public

            Report from mPING: Quarter (1.00 in.).

0123 PM     Hail             2 NW Castlewood Canyon  39.37N 104.80W
07/20/2023  E0.75 inch       Douglas            CO   Public

            Report from mPING: Dime (0.75 in.).

&&
Special weather statement, Jul 20, 3:50 PM MDT, 2 hours 32 minutes before
Special Weather Statement
National Weather Service Denver CO
350 PM MDT Thu Jul 20 2023

COZ036-039-040-202215-
Boulder And Jefferson Counties Below 6000 Feet/West Broomfield County
CO-
North Douglas County Below 6000 Feet/Denver/West Adams and Arapahoe
Counties/East Broomfield County CO-
Jefferson and West Douglas Counties Above  6000 Feet/Gilpin/Clear
Creek/Northeast Park Counties Below 9000 Feet CO-
350 PM MDT Thu Jul 20 2023

...A strong thunderstorm will impact portions of north central
Douglas, southwestern Arapahoe, southwestern Denver and northern
Jefferson Counties through 415 PM MDT...

At 350 PM MDT, Doppler radar was tracking a strong thunderstorm near
Red Rocks Park, or 13 miles west of Denver, moving southeast at 30
mph.

HAZARD...Winds in excess of 40 mph and penny 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...
Denver, western Aurora, Lakewood, southwestern Centennial, Highlands
Ranch, Littleton, Englewood, southwestern Wheat Ridge, Golden,
Greenwood Village, Evergreen, Sheridan, Morrison, Idledale, Tiny
Town, Chatfield Reservoir, Kittredge, Red Rocks Park, Indian Hills
and Louviers.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

A Severe Thunderstorm Watch remains in effect until 900 PM MDT for
central and northeastern Colorado.

&&

LAT...LON 3947 10501 3967 10534 3980 10526 3970 10481
      3953 10496 3953 10497 3952 10498 3951 10498
TIME...MOT...LOC 2150Z 296DEG 27KT 3970 10521

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...40 MPH

HIRIS
Local storm report, Jul 20, 4:10 PM MDT, 2 hours 12 minutes before
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Local storm report, Jul 20, 4:13 PM MDT, 2 hours 9 minutes before
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Local storm report, Jul 20, 4:27 PM MDT, 1 hour 55 minutes before
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Special weather statement, Jul 20, 4:59 PM MDT, 1 hour 23 minutes before
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The office that day

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

IssuedProductOfficeCountiesLasted
Jul 20, 6:07 PM MDTAreal Flood AdvisoryBOULincoln, Washington3 hr
Jul 20, 9:40 PM MDTAreal Flood AdvisoryBOULincoln3 hr
Jul 21, 4:58 PM MDTSpecial Weather StatementBOUWeld47 min
Jul 21, 5:07 PM MDTSpecial Weather StatementBOUBroomfield53 min
Jul 21, 5:25 PM MDTSpecial Weather StatementBOUWeld35 min
Jul 21, 5:42 PM MDTSpecial Weather StatementBOUBroomfield33 min

Nearby

Severe Thunderstorm Warnings in Colorado, 2023Every severe thunderstorm warning in 2023

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.