Alert archive / Colorado / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 35, NWS Denver/Boulder, CO

May 25, 2023Adams County, Arapahoe County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at May 25, 2023, 7:40 PM MDT for Adams County, Arapahoe County, Colorado. It was in force for 50 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 25, 2023, 7:40 PM MDT (01:40 UTC)
Expired
May 25, 2023, 8:30 PM MDT
In force
50 min
Issued by
NWS Denver/Boulder, CO
Area
Storm-based polygon
Hail
1.0 in
Wind
50.0 mph

Counties Adams County, CO, Arapahoe County, CO

The radar

The Denver radar (KFTG), 18 km from the middle of the area, began a volume at 01:41 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

N. Platte/Lee Bi, NE (KLBF), launched 00:00Z, 1.7 hours before the alert went out and 351 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-pSkew-T log-p diagram, N. Platte/Lee Bi, NE at 00:00Z on 2023-05-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, N. Platte/Lee Bi, NE at 00:00Z on 2023-05-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 0 square meters per square second.1939Sfc1 km3 km6 km9 kmRMLM
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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1238 m above ground
0-6 km bulk shear
10 kt
0-1 km storm-relative helicity
0 m²/s²
0-3 km storm-relative helicity
-52 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

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 May 25, 6:40 PM MDT, 1 hour earlier.

Area forecast discussion, May 25, 6:40 PM MDT, 1 hour before
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Hazardous weather outlook, May 25, 11:08 AM MDT, 8 hours 32 minutes before
Hazardous Weather Outlook
National Weather Service Denver/Boulder CO
1108 AM MDT Thu May 25 2023

COZ030>051-261715-
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-
1108 AM MDT Thu May 25 2023

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

.DAY ONE...Today and Tonight

Scattered thunderstorms will develop this afternoon and continue
through the evening hours. A couple of the stronger storms could
produce large hail around an inch in diameter, wind gusts up to 60
mph, heavy rain, and frequent lightning. A limited threat of burn
area flash flooding is also forecast today, mainly over the
eastern portions of the Cameron Peak burn area. The greatest
threat of severe weather is over Elbert and Lincoln counties this
evening where there will be more moisture.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

An active weather pattern will continue through the weekend, with
afternoon showers and thunderstorms likely. A few strong to
severe storms are possible across the plains each afternoon. Heavy
rain will also be possible with some threat of burn area flash
flood flooding.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed today or tonight.

Gimmestad/Mensch

In the hours before

Local storm report, May 25, 3:51 PM MDT, 3 hours 49 minutes before
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Special weather statement, May 25, 4:20 PM MDT, 3 hours 20 minutes before
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Local storm report, May 25, 4:22 PM MDT, 3 hours 18 minutes before
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Special weather statement, May 25, 5:18 PM MDT, 2 hours 22 minutes before
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Special weather statement, May 25, 5:54 PM MDT, 1 hour 46 minutes before
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Local storm report, May 25, 6:31 PM MDT, 1 hour 9 minutes before
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The office that day

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

IssuedProductOfficeCountiesLasted
May 25, 8:24 PM MDTSpecial Weather StatementBOUMorgan51 min
May 25, 9:14 PM MDTSpecial Weather StatementBOUMorgan46 min
May 25, 9:39 PM MDTSpecial Weather StatementBOULogan51 min
May 26, 12:08 PM MDTSpecial Weather StatementBOUBoulder52 min
May 26, 1:16 PM MDTAreal Flood AdvisoryBOUGrand6 days
May 26, 1:44 PM MDTSpecial Weather StatementBOUJefferson46 min
May 26, 2:21 PM MDTSevere Thunderstorm WarningBOUAdams, Broomfield, Denver, Jefferson39 min
May 26, 2:25 PM MDTSevere Thunderstorm WarningBOUWeld50 min
May 26, 2:40 PM MDTSevere Thunderstorm WarningBOUBoulder, Larimer, Weld22 min
May 26, 2:58 PM MDTSevere Thunderstorm WarningBOUWeld47 min
May 26, 3:12 PM MDTSevere Thunderstorm WarningBOUWeld48 min
May 26, 3:13 PM MDTSevere Thunderstorm WarningBOUAdams, Arapahoe, Denver, Weld47 min
May 26, 3:30 PM MDTAreal Flood AdvisoryBOUWeld3 hr
May 26, 3:56 PM MDTSevere Thunderstorm WarningBOUWeld21 min
May 26, 4:02 PM MDTTornado WarningBOUWeld28 min
May 26, 4:14 PM MDTSevere Thunderstorm WarningBOUWeld25 min
May 26, 4:16 PM MDTSpecial Weather StatementBOUArapahoe, Elbert, Morgan44 min
May 26, 4:24 PM MDTTornado WarningBOUWeld9 min
May 26, 4:32 PM MDTSevere Thunderstorm WarningBOUElbert43 min
May 26, 4:49 PM MDTTornado WarningBOUMorgan26 min
May 26, 4:55 PM MDTSevere Thunderstorm WarningBOUAdams, Arapahoe50 min
May 26, 5:43 PM MDTSevere Thunderstorm WarningBOULogan, Morgan, Washington47 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.