Alert archive / Utah / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 29, NWS Grand Junction, CO

June 6, 2020Grand County, Utah

NWS Grand Junction, CO issued this severe thunderstorm warning at Jun 6, 2020, 1:00 PM MDT for Grand County, Utah. It was in force for 30 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: Jun 6, 2020, 1:00 PM MDT (19:00 UTC)
Expired: Jun 6, 2020, 1:30 PM MDT
In force: 30 min
Issued by: NWS Grand Junction, CO
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 mph

County Grand County, UT

The radar

The Grand Junction radar (KGJX), 118 km from the middle of the area, began a volume at 19:00 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
Jun 6, 9:48 AM MDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Grand Junction, CO (KGJT), launched 12:00Z, 7.0 hours before the alert went out and 94 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: 10 J/kg
Mixed-layer CIN: -173 J/kg
Mixed-layer LCL: 1157 m above ground
0-6 km bulk shear: 54 kt
0-1 km storm-relative helicity: 23 m²/s²
0-3 km storm-relative helicity: 129 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 Grand Junction, CO wrote its last area forecast discussion before this severe thunderstorm warning went out at Jun 6, 11:47 AM MDT, 1 hour 13 minutes earlier.

Area forecast discussion, Jun 6, 11:47 AM MDT, 1 hour 13 minutes before

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Hazardous weather outlook, Jun 6, 4:25 AM MDT, 8 hours 35 minutes before

Hazardous Weather Outlook
National Weather Service Grand Junction CO
425 AM MDT Sat Jun 6 2020

COZ001>014-017>023-UTZ022>025-027>029-071030-
Lower Yampa River Basin-Central Yampa River Basin-
Roan and Tavaputs Plateaus-Elkhead and Park Mountains-
Upper Yampa River Basin-Grand Valley-Debeque to Silt Corridor-
Central Colorado River Basin-Grand and Battlement Mesas-
Gore and Elk Mountains/Central Mountain Valleys-
Central Gunnison and Uncompahgre River Basin-
West Elk and Sawatch Mountains-Flat Tops-
Upper Gunnison River Valley-Uncompahgre Plateau and Dallas Divide-
Northwest San Juan Mountains-Southwest San Juan Mountains-
Paradox Valley/Lower Dolores River-
Four Corners/Upper Dolores River-Animas River Basin-
San Juan River Basin-Southeast Utah-Eastern Uinta Mountains-
Eastern Uinta Basin-Tavaputs Plateau-Arches/Grand Flat-
La Sal and Abajo Mountains-Canyonlands/Natural Bridges-
425 AM MDT Sat Jun 6 2020

This hazardous weather outlook is for eastern Utah and western
Colorado.

.DAY ONE...Today and Tonight

A system will be moving over the forecast area today bringing
rain, heavy at times, along with some thunderstorms. The heavy
rain will increase chances for flash flooding, especially over
canyon country and recent burn scars, so a Flash Flood Watch is in
effect for eastern Utah and southwest Colorado through 4 pm.
Gusty winds and hail will be possible through the day under the
stronger thunderstorms. Wind gusts could exceed 60 mph even
without a storm especially above the treeline.

.DAYS TWO THROUGH SEVEN...Sunday through Friday

Critical fire weather conditions are possible across Southeast
Utah and southwest Colorado Sunday into Monday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is needed later this morning and into the
afternoon as the chance for severe thunderstorms increases across
the area. The main threat with these storms will be damaging wind
gusts.

In the hours before

Special weather statement, Jun 6, 12:39 PM MDT, 21 minutes before

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Special weather statement, Jun 6, 12:39 PM MDT, 21 minutes before

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Local storm report, Jun 6, 12:41 PM MDT, 19 minutes before

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Local storm report, Jun 6, 12:45 PM MDT, 15 minutes before

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Local storm report, Jun 6, 12:49 PM MDT, 11 minutes before

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Local storm report, Jun 6, 12:58 PM MDT, 2 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
Jun 5, 7:07 PM MDT	Special Weather Statement	GJT	Delta, Mesa	38 min
Jun 5, 7:41 PM MDT	Severe Thunderstorm Warning	GJT	Garfield, Mesa	34 min
Jun 5, 8:22 PM MDT	Special Weather Statement	GJT	Garfield, Rio Blanco	38 min
Jun 5, 9:26 PM MDT	Severe Thunderstorm Warning	GJT	Moffat, Rio Blanco	34 min
Jun 5, 10:01 PM MDT	Special Weather Statement	GJT	Moffat	29 min
Jun 6, 2:16 AM MDT	Wind Advisory	GJT	Archuleta, Delta, Dolores, Eagle, Garfield, Gunnison and 9 more	18 hr
Jun 6, 9:45 AM MDT	Special Weather Statement	GJT		30 min
Jun 6, 10:24 AM MDT	Severe Thunderstorm Warning	GJT	Montrose, San Miguel	36 min
Jun 6, 10:36 AM MDT	Special Weather Statement	GJT	Dolores, Montezuma	24 min
Jun 6, 10:44 AM MDT	Severe Thunderstorm Warning	GJT	Dolores, Montezuma	31 min
Jun 6, 10:53 AM MDT	Severe Thunderstorm Warning	GJT	Dolores, Mesa, Montrose, San Miguel	22 min
Jun 6, 10:59 AM MDT	Special Weather Statement	GJT	La Plata	46 min
Jun 6, 11:13 AM MDT	Severe Thunderstorm Warning	GJT	Dolores, Montezuma, San Miguel	47 min
Jun 6, 11:18 AM MDT	Severe Thunderstorm Warning	GJT	Delta, Mesa, Montrose, San Miguel	27 min
Jun 6, 11:19 AM MDT	Severe Thunderstorm Warning	GJT	Garfield, Mesa	41 min
Jun 6, 11:35 AM MDT	Severe Thunderstorm Warning	GJT	Delta, Garfield, Mesa, Montrose, Rio Blanco	25 min
Jun 6, 11:47 AM MDT	Special Weather Statement	GJT	Ouray, San Juan	43 min
Jun 6, 11:55 AM MDT	Severe Thunderstorm Warning	GJT	Garfield, Mesa, Rio Blanco	50 min
Jun 6, 11:56 AM MDT	Areal Flood Advisory	GJT	Mesa	3 hr
Jun 6, 11:59 AM MDT	Severe Thunderstorm Warning	GJT	Delta, Garfield, Mesa, Montrose, Rio Blanco	31 min
Jun 6, 12:01 PM MDT	Areal Flood Advisory	GJT	Delta	3 hr
Jun 6, 12:28 PM MDT	Severe Thunderstorm Warning	GJT	Garfield, Mesa, Rio Blanco	32 min
Jun 6, 12:34 PM MDT	Severe Thunderstorm Warning	GJT	Moffat, Rio Blanco	41 min
Jun 6, 12:35 PM MDT	Special Weather Statement	GJT	Archuleta, Hinsdale, San Juan	40 min
Jun 6, 12:39 PM MDT	Special Weather Statement	GJT	Delta	36 min
Jun 6, 12:47 PM MDT	Areal Flood Advisory	GJT	Rio Blanco	58 min
Jun 6, 12:59 PM MDT	Severe Thunderstorm Warning	GJT	Eagle, Garfield, Moffat, Rio Blanco, Routt	31 min
Jun 6, 1:16 PM MDT	Special Weather Statement	GJT	Eagle	44 min
Jun 6, 1:17 PM MDT	Severe Thunderstorm Warning	GJT	Moffat	28 min
Jun 6, 1:28 PM MDT	Severe Thunderstorm Warning	GJT	Eagle, Garfield, Moffat, Rio Blanco, Routt	32 min
Jun 6, 1:30 PM MDT	Special Weather Statement	GJT	Archuleta	45 min
Jun 6, 1:38 PM MDT	Areal Flood Advisory	GJT	Moffat, Routt	52 min
Jun 6, 1:38 PM MDT	Special Weather Statement	GJT		52 min
Jun 6, 1:55 PM MDT	Severe Thunderstorm Warning	GJT	Moffat, Rio Blanco, Routt	35 min
Jun 6, 2:06 PM MDT	Special Weather Statement	GJT	Rio Blanco	39 min
Jun 6, 2:10 PM MDT	Special Weather Statement	GJT	Eagle, Pitkin	35 min
Jun 6, 2:15 PM MDT	Areal Flood Advisory	GJT	Archuleta	3 hr
Jun 6, 2:25 PM MDT	Special Weather Statement	GJT	Archuleta	35 min
Jun 6, 2:27 PM MDT	Special Weather Statement	GJT		48 min
Jun 6, 2:32 PM MDT	Areal Flood Advisory	GJT	Moffat, Rio Blanco	118 min
Jun 6, 2:36 PM MDT	Red Flag Warning	GJT	Delta, Dolores, Garfield, La Plata, Mesa, Montezuma and 3 more	31 hr
Jun 6, 2:46 PM MDT	Special Weather Statement	GJT	Eagle, Pitkin	29 min
Jun 6, 2:54 PM MDT	Severe Thunderstorm Warning	GJT	Moffat	13 min
Jun 6, 3:08 PM MDT	Areal Flood Advisory	GJT	Hinsdale, La Plata, San Juan	5 hr
Jun 6, 4:46 PM MDT	River Flood Advisory	GJT	La Plata	44 hr
Jun 5, 6:39 PM MDT	Special Weather Statement	GJT	San Juan	51 min
Jun 5, 7:10 PM MDT	Special Weather Statement	GJT	Grand	50 min
Jun 5, 7:27 PM MDT	Severe Thunderstorm Warning	GJT	Grand	33 min
Jun 5, 8:02 PM MDT	Special Weather Statement	GJT	Uintah	43 min
Jun 5, 9:32 PM MDT	Special Weather Statement	GJT	Daggett	43 min
Jun 6, 8:59 AM MDT	Special Weather Statement	GJT	San Juan	31 min
Jun 6, 9:29 AM MDT	Severe Thunderstorm Warning	GJT	San Juan	31 min
Jun 6, 9:38 AM MDT	Flash Flood Warning	GJT	San Juan	3 hr
Jun 6, 9:39 AM MDT	Severe Thunderstorm Warning	GJT	San Juan	36 min
Jun 6, 9:54 AM MDT	Severe Thunderstorm Warning	GJT	San Juan	36 min
Jun 6, 10:09 AM MDT	Severe Thunderstorm Warning	GJT	San Juan	36 min
Jun 6, 10:17 AM MDT	Special Weather Statement	GJT	Grand	28 min
Jun 6, 10:24 AM MDT	Severe Thunderstorm Warning	GJT	Grand	36 min
Jun 6, 10:33 AM MDT	Severe Thunderstorm Warning	GJT	Grand, San Juan	42 min
Jun 6, 11:24 AM MDT	Areal Flood Advisory	GJT	San Juan	3 hr
Jun 6, 11:29 AM MDT	Areal Flood Advisory	GJT	Grand	2 hr
Jun 6, 11:52 AM MDT	Areal Flood Advisory	GJT	Grand	3 hr
Jun 6, 1:03 PM MDT	Areal Flood Advisory	GJT	Grand	103 min
Jun 6, 1:24 PM MDT	Severe Thunderstorm Warning	GJT	Grand	51 min
Jun 6, 2:04 PM MDT	Special Weather Statement	GJT	Grand	41 min

Nearby

Severe Thunderstorm Warnings in Utah, 2020 Every severe thunderstorm warning in 2020

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.