Alert archive / Colorado / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 9, NWS Grand Junction, CO

September 8, 2019Garfield County, Colorado

NWS Grand Junction, CO issued this severe thunderstorm warning at Sep 8, 2019, 5:58 PM MDT for Garfield County, Colorado. It was in force for 32 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 8, 2019, 5:58 PM MDT (23:58 UTC)
Expired: Sep 8, 2019, 6:30 PM MDT
In force: 32 min
Issued by: NWS Grand Junction, CO
Area: Storm-based polygon
Hail: 0.75 in
Wind: 70.0 mph

County Garfield County, CO

The radar

The Grand Junction radar (KGJX), 65 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

Salt Lake City I, UT (KSLC), launched 12:00Z, 12.0 hours before the alert went out and 364 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: 22 J/kg
Mixed-layer CIN: -315 J/kg
Mixed-layer LCL: 2601 m above ground
0-6 km bulk shear: 29 kt
0-1 km storm-relative helicity: 147 m²/s²
0-3 km storm-relative helicity: 167 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 Grand Junction, CO wrote its last area forecast discussion before this severe thunderstorm warning went out at Sep 8, 5:50 PM MDT, 8 minutes earlier.

Area forecast discussion, Sep 8, 5:50 PM MDT, 8 minutes before

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Hazardous weather outlook, Sep 8, 6:21 AM MDT, 11 hours 37 minutes before

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In the hours before

Local storm report, Sep 8, 4:50 PM MDT, 1 hour 8 minutes before

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Special weather statement, Sep 8, 5:03 PM MDT, 55 minutes before

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Special weather statement, Sep 8, 5:26 PM MDT, 32 minutes before

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Special weather statement, Sep 8, 5:26 PM MDT, 32 minutes before

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Local storm report, Sep 8, 5:56 PM MDT, 2 minutes before

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Local storm report, Sep 8, 5:58 PM MDT, 0 minutes before

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The office that day

Everything else NWS Grand Junction, CO issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Sep 8, 4:27 AM MDT	Flash Flood Watch	GJT	Archuleta, Dolores, Eagle, Garfield, Hinsdale, La Plata and 4 more	14 hr
Sep 8, 12:03 PM MDT	Special Weather Statement	GJT	Rio Blanco	27 min
Sep 8, 12:49 PM MDT	Special Weather Statement	GJT	Rio Blanco	26 min
Sep 8, 1:45 PM MDT	Special Weather Statement	GJT	Pitkin	30 min
Sep 8, 2:17 PM MDT	Special Weather Statement	GJT	Routt	58 min
Sep 8, 2:19 PM MDT	Special Weather Statement	GJT	Eagle	56 min
Sep 8, 2:33 PM MDT	Severe Thunderstorm Warning	GJT	Eagle, Garfield, Routt	27 min
Sep 8, 3:39 PM MDT	Special Weather Statement	GJT	Mesa	36 min
Sep 8, 3:55 PM MDT	Special Weather Statement	GJT	Mesa	35 min
Sep 8, 4:03 PM MDT	Severe Thunderstorm Warning	GJT	Moffat, Rio Blanco	27 min
Sep 8, 4:31 PM MDT	Special Weather Statement	GJT	Rio Blanco	29 min
Sep 8, 4:32 PM MDT	Special Weather Statement	GJT	Garfield	43 min
Sep 8, 5:03 PM MDT	Special Weather Statement	GJT	Garfield	27 min
Sep 8, 5:26 PM MDT	Special Weather Statement	GJT	Moffat	34 min
Sep 8, 5:32 PM MDT	Severe Thunderstorm Warning	GJT	Garfield	28 min
Sep 8, 3:34 PM MDT	Special Weather Statement	GJT	Uintah	26 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.