Alert archive / Colorado / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 277, NWS Denver/Boulder, CO

September 11, 2019Logan County, Morgan County, Weld County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Sep 11, 2019, 6:15 PM MDT for Logan County, Morgan County, Weld County, Colorado. It was in force for 45 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: Sep 11, 2019, 6:15 PM MDT (00:15 UTC)
Expired: Sep 11, 2019, 7:00 PM MDT
In force: 45 min
Issued by: NWS Denver/Boulder, CO
Area: Storm-based polygon
Hail: 1.5 in
Wind: 50.0 mph

Counties Logan County, CO, Morgan County, CO, Weld County, CO

The radar

The Denver radar (KFTG), 104 km from the middle of the area, began a volume at 00:19 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Sep 11, 2:31 PM MDT	Severe Thunderstorm Watch	SPC	10 hr

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 Sep 11, 2:38 PM MDT, 3 hours 37 minutes earlier.

Area forecast discussion, Sep 11, 2:38 PM MDT, 3 hours 37 minutes before

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Hazardous weather outlook, Sep 11, 10:32 AM MDT, 7 hours 43 minutes before

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In the hours before

Local storm report, Sep 11, 4:38 PM MDT, 1 hour 37 minutes before

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Local storm report, Sep 11, 4:41 PM MDT, 1 hour 34 minutes before

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Local storm report, Sep 11, 4:48 PM MDT, 1 hour 27 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DENVER CO
448 PM MDT WED SEP 11 2019

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0437 PM     HAIL             1 NW LONGMONT           40.19N 105.12W
09/11/2019  M1.25 INCH       BOULDER            CO   TRAINED SPOTTER

0434 PM     HAIL             1 W LONGMONT            40.18N 105.13W
09/11/2019  U1.00 INCH       BOULDER            CO   TRAINED SPOTTER

            REPORT FROM MPING: QUARTER (1.00 IN.).

0430 PM     HAIL             1 NNE LONGMONT          40.19N 105.11W
09/11/2019  M1.00 INCH       BOULDER            CO   TRAINED SPOTTER

0428 PM     HAIL             LONGMONT                40.18N 105.11W
09/11/2019  M1.00 INCH       BOULDER            CO   TRAINED SPOTTER

0427 PM     HAIL             3 SE HYGIENE            40.14N 105.15W
09/11/2019  M1.00 INCH       BOULDER            CO   TRAINED SPOTTER

0427 PM     HAIL             2 N LONGMONT            40.21N 105.11W
09/11/2019  M1.50 INCH       BOULDER            CO   TRAINED SPOTTER

&&

Local storm report, Sep 11, 5:15 PM MDT, 1 hour before

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Local storm report, Sep 11, 5:31 PM MDT, 44 minutes before

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Local storm report, Sep 11, 5:51 PM MDT, 24 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
Sep 11, 6:40 PM MDT	Severe Thunderstorm Warning	BOU	Morgan, Weld	50 min
Sep 11, 7:01 PM MDT	Severe Thunderstorm Warning	BOU	Logan, Phillips, Sedgwick	13 min
Sep 11, 7:11 PM MDT	Severe Thunderstorm Warning	BOU	Logan, Phillips, Sedgwick	38 min
Sep 11, 7:31 PM MDT	Special Weather Statement	BOU	Morgan	29 min
Sep 11, 7:48 PM MDT	Severe Thunderstorm Warning	BOU	Logan, Phillips, Sedgwick	27 min
Sep 11, 8:15 PM MDT	Special Weather Statement	BOU	Logan	30 min
Sep 11, 8:30 PM MDT	Special Weather Statement	BOU	Lincoln	45 min
Sep 11, 8:54 PM MDT	Special Weather Statement	BOU	Weld	36 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; radar from the NEXRAD Level II archive.