Alert archive / Colorado / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 245, NWS Denver/Boulder, CO

August 22, 2019Logan County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Aug 22, 2019, 6:01 PM MDT for Logan County, Colorado. It was in force for 20 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 22, 2019, 6:01 PM MDT (00:01 UTC)
Expired: Aug 22, 2019, 6:21 PM MDT
In force: 20 min
Issued by: NWS Denver/Boulder, CO
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

County Logan County, CO

The radar

The Cheyenne radar (KCYS), 150 km from the middle of the area, began a volume at 00:02 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

Denver, CO (KDNR), launched 00:00Z, 0.0 hours before the alert went out and 96 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: 19 J/kg
Mixed-layer CIN: -110 J/kg
Mixed-layer LCL: 3469 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: 50 m²/s²
0-3 km storm-relative helicity: 67 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 22, 2:59 PM MDT, 3 hours 2 minutes earlier.

Area forecast discussion, Aug 22, 2:59 PM MDT, 3 hours 2 minutes before

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Hazardous weather outlook, Aug 22, 10:32 AM MDT, 7 hours 29 minutes before

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In the hours before

Local storm report, Aug 22, 2:01 PM MDT, 4 hours before

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Special weather statement, Aug 22, 3:23 PM MDT, 2 hours 38 minutes before

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Special weather statement, Aug 22, 3:58 PM MDT, 2 hours 3 minutes before

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Local storm report, Aug 22, 4:08 PM MDT, 1 hour 53 minutes before

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Special weather statement, Aug 22, 4:45 PM MDT, 1 hour 16 minutes before

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Local storm report, Aug 22, 5:02 PM MDT, 59 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 23, 2:36 PM MDT	Severe Thunderstorm Warning	BOU	Elbert	21 min
Aug 23, 3:03 PM MDT	Fire Weather Watch	BOU	Boulder, Grand, Jackson, Larimer, Park, Summit and 1 more	23 hr
Aug 23, 3:23 PM MDT	Severe Thunderstorm Warning	BOU	Adams	26 min
Aug 23, 4:13 PM MDT	Severe Thunderstorm Warning	BOU	Weld	32 min
Aug 23, 5:41 PM MDT	Special Weather Statement	BOU	Weld	34 min
Aug 23, 5:47 PM MDT	Severe Thunderstorm Warning	BOU	Weld	43 min

Nearby

Severe Thunderstorm Warnings in Colorado, 2019 Every severe thunderstorm warning in 2019

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.