Alert archive / Colorado / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 117, NWS Denver/Boulder, CO

August 11, 2017Weld County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Aug 11, 2017, 7:40 PM MDT for Weld County, Colorado. It was in force for 16 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 11, 2017, 7:40 PM MDT (01:40 UTC)
Expired: Aug 11, 2017, 7:56 PM MDT
In force: 16 min
Issued by: NWS Denver/Boulder, CO
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

County Weld County, CO

The radar

The Cheyenne radar (KCYS), 75 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.

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 11, 3:33 PM MDT, 4 hours 7 minutes earlier.

Area forecast discussion, Aug 11, 3:33 PM MDT, 4 hours 7 minutes before

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Hazardous weather outlook, Aug 11, 11:03 AM MDT, 8 hours 37 minutes before

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In the hours before

Special weather statement, Aug 11, 7:28 PM MDT, 12 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 11, 7:28 PM MDT	Special Weather Statement	BOU	Weld	62 min
Aug 12, 2:41 PM MDT	Special Weather Statement	BOU	Weld	34 min
Aug 12, 3:06 PM MDT	Areal Flood Advisory	BOU	Weld	3 hr
Aug 12, 3:18 PM MDT	Special Weather Statement	BOU	Jefferson	27 min
Aug 12, 3:38 PM MDT	Areal Flood Advisory	BOU	Jefferson	97 min
Aug 12, 3:57 PM MDT	Special Weather Statement	BOU	Broomfield	33 min
Aug 12, 4:33 PM MDT	Severe Thunderstorm Warning	BOU	Washington	42 min
Aug 12, 4:54 PM MDT	Severe Thunderstorm Warning	BOU	Washington	51 min
Aug 12, 4:59 PM MDT	Severe Thunderstorm Warning	BOU	Adams	31 min
Aug 12, 5:04 PM MDT	Areal Flood Advisory	BOU	Adams, Arapahoe	116 min
Aug 12, 5:26 PM MDT	Special Weather Statement	BOU	Elbert	49 min
Aug 12, 5:30 PM MDT	Tornado Warning Tornado observed	BOU	Washington	30 min
Aug 12, 5:35 PM MDT	Severe Thunderstorm Warning	BOU	Elbert, Lincoln	40 min
Aug 12, 5:38 PM MDT	Severe Thunderstorm Warning	BOU	Lincoln, Washington	52 min
Aug 12, 5:52 PM MDT	Areal Flood Advisory	BOU	Elbert, Lincoln, Washington	4 hr
Aug 12, 5:57 PM MDT	Severe Thunderstorm Warning	BOU	Lincoln	29 min

Nearby

Severe Thunderstorm Warnings in Colorado, 2017 Every severe thunderstorm warning in 2017

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.