Alert archive / Colorado / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 68, NWS Denver/Boulder, CO

May 31, 20236 counties in Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at May 31, 2023, 3:03 PM MDT for 6 counties in Colorado. It was in force for 42 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: May 31, 2023, 3:03 PM MDT (21:03 UTC)
Expired: May 31, 2023, 3:45 PM MDT
In force: 42 min
Issued by: NWS Denver/Boulder, CO
Area: Storm-based polygon
Hail: 1.0 in
Wind: 50.0 mph

Counties Adams County, CO, Boulder County, CO, Broomfield County, CO, Denver County, CO, Jefferson County, CO, Weld County, CO

The radar

The Denver radar (KFTG), 35 km from the middle of the area, began a volume at 21:03 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.

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 May 31, 11:32 AM MDT, 3 hours 31 minutes earlier.

Area forecast discussion, May 31, 11:32 AM MDT, 3 hours 31 minutes before

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Hazardous weather outlook, May 31, 10:51 AM MDT, 4 hours 12 minutes before

Hazardous Weather Outlook
National Weather Service Denver/Boulder CO
1051 AM MDT Wed May 31 2023

COZ030>051-011700-
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-
1051 AM MDT Wed May 31 2023

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

.DAY ONE...Today and Tonight

Scattered storms and showers are likely starting this afternoon
across the foothills and mountains. These storms will push into
the I-25 corridor and eastern plains late afternoon and early
evening. Cannot rule out an isolated storm reaching severe
thresholds. The main threats with stronger storms will be gusty
outflow winds and small hail.

.DAYS TWO THROUGH SEVEN...Thursday through Tuesday

Thunderstorm activity is expected to increase through this
weekend, with a period of steady rain possible Saturday. The main
threat will be locally heavy rain and burn area flooding. A
gradual decrease in thunderstorms is expected early next week, but
there will still be a threat of heavy rain with some of the
storms.

.SPOTTER INFORMATION STATEMENT...

Spotters are encouraged to report heavy rain, hail, or
significant weather which is always appreciated.

AD/Gimmestad

In the hours before

Special weather statement, May 31, 1:18 PM MDT, 1 hour 45 minutes before

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Special weather statement, May 31, 2:11 PM MDT, 52 minutes before

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Special weather statement, May 31, 2:53 PM MDT, 10 minutes before

Special Weather Statement
National Weather Service Denver CO
253 PM MDT Wed May 31 2023

COZ039-312145-
Boulder And Jefferson Counties Below 6000 Feet/West Broomfield County
CO-
253 PM MDT Wed May 31 2023

...A strong thunderstorm will impact portions of southeastern Boulder
County through 345 PM MDT...

At 253 PM MDT, Doppler radar was tracking a strong thunderstorm near
Eldorado Springs, or 20 miles northwest of Denver, moving north at 15
mph.

HAZARD...Winds in excess of 40 mph and pea 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...
Arvada, western Westminster, Boulder, western Broomfield, Lafayette,
Louisville, Erie, Superior, Eldorado Springs and Niwot.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

&&

LAT...LON 4008 10506 3998 10505 3984 10517 3985 10521
      3986 10520 3988 10520 3992 10523 3993 10524
      3993 10528 3994 10527 3998 10527 4001 10530
      4014 10528
TIME...MOT...LOC 2053Z 200DEG 15KT 3994 10522

MAX HAIL SIZE...0.25 IN
MAX WIND GUST...40 MPH

MENSCH

The office that day

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

Issued	Product	Office	Counties	Lasted
May 30, 6:46 PM MDT	Severe Thunderstorm Warning	BOU	Logan, Phillips, Sedgwick	44 min
May 30, 6:57 PM MDT	Special Weather Statement	BOU	Lincoln	48 min
May 30, 7:28 PM MDT	Severe Thunderstorm Warning	BOU	Logan, Sedgwick	32 min
May 30, 7:36 PM MDT	Severe Thunderstorm Warning	BOU	Phillips	39 min
May 30, 7:58 PM MDT	Severe Thunderstorm Warning	BOU	Phillips, Sedgwick	47 min
May 30, 8:09 PM MDT	Severe Thunderstorm Warning Considerable damage threat	BOU	Phillips, Sedgwick	51 min
May 31, 1:18 PM MDT	Special Weather Statement	BOU	Gilpin	42 min
May 31, 2:11 PM MDT	Special Weather Statement	BOU	Gilpin	49 min
May 31, 2:53 PM MDT	Special Weather Statement	BOU	Broomfield	52 min
May 31, 3:40 PM MDT	Severe Thunderstorm Warning	BOU	Boulder, Weld	50 min
May 31, 4:04 PM MDT	Severe Thunderstorm Warning	BOU	Boulder, Larimer, Weld	41 min
May 31, 4:38 PM MDT	Severe Thunderstorm Warning	BOU	Weld	18 min
May 31, 4:42 PM MDT	Special Weather Statement	BOU	Weld	48 min
May 31, 5:01 PM MDT	Special Weather Statement	BOU	Weld	44 min

Nearby

Severe Thunderstorm Warnings in Colorado, 2023 Every 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.