Alert archive / Colorado / Severe Thunderstorm Warnings in 2023

Severe Thunderstorm Warning 368, NWS Denver/Boulder, CO

August 2, 2023Logan County, Sedgwick County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Aug 2, 2023, 2:36 PM MDT for Logan County, Sedgwick County, Colorado. It was in force for 24 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 2, 2023, 2:36 PM MDT (20:36 UTC)
Expired: Aug 2, 2023, 3:00 PM MDT
In force: 24 min
Issued by: NWS Denver/Boulder, CO
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

Counties Logan County, CO, Sedgwick County, CO

The radar

The Cheyenne radar (KCYS), 179 km from the middle of the area, began a volume at 20:39 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 12:00Z, 8.6 hours before the alert went out and 183 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: 5 J/kg
Mixed-layer CIN: -264 J/kg
Mixed-layer LCL: 1628 m above ground
0-6 km bulk shear: 10 kt
0-1 km storm-relative helicity: -20 m²/s²
0-3 km storm-relative helicity: -9 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 Aug 2, 12:41 PM MDT, 1 hour 55 minutes earlier.

Area forecast discussion, Aug 2, 12:41 PM MDT, 1 hour 55 minutes before

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Hazardous weather outlook, Aug 2, 11:16 AM MDT, 3 hours 20 minutes before

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In the hours before

Special weather statement, Aug 2, 2:01 PM MDT, 35 minutes before

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Special weather statement, Aug 2, 2:31 PM MDT, 5 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 1, 6:10 PM MDT	Areal Flood Advisory	BOU	Boulder	3 hr
Aug 1, 6:11 PM MDT	Severe Thunderstorm Warning	BOU	Weld	34 min
Aug 1, 6:21 PM MDT	Severe Thunderstorm Warning	BOU	Morgan	24 min
Aug 1, 6:43 PM MDT	Severe Thunderstorm Warning	BOU	Morgan	32 min
Aug 1, 6:49 PM MDT	Severe Thunderstorm Warning	BOU	Morgan	41 min
Aug 1, 6:57 PM MDT	Flash Flood Warning	BOU	Morgan	3 hr
Aug 1, 8:25 PM MDT	Special Weather Statement	BOU	Washington	50 min
Aug 1, 9:16 PM MDT	Areal Flood Advisory	BOU	Larimer	119 min
Aug 2, 2:01 PM MDT	Special Weather Statement	BOU	Morgan	44 min
Aug 2, 2:22 PM MDT	Areal Flood Advisory	BOU	Weld	3 hr
Aug 2, 2:31 PM MDT	Special Weather Statement	BOU	Logan	44 min
Aug 2, 3:10 PM MDT	Areal Flood Advisory	BOU	Larimer	3 hr
Aug 2, 3:18 PM MDT	Special Weather Statement	BOU	Logan	42 min
Aug 2, 3:24 PM MDT	Severe Thunderstorm Warning	BOU	Logan	51 min
Aug 2, 3:34 PM MDT	Areal Flood Advisory	BOU	Logan, Sedgwick	3 hr
Aug 2, 4:11 PM MDT	Special Weather Statement	BOU	Phillips, Sedgwick	49 min
Aug 2, 5:13 PM MDT	Areal Flood Advisory	BOU	Phillips, Sedgwick	3 hr

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.