Alert archive / Colorado / Flash Flood Warnings in 2023

Flash Flood Warning 1, NWS Grand Junction, CO

August 1, 2023Eagle County, Garfield County, Pitkin County, Colorado

NWS Grand Junction, CO issued this flash flood warning at Aug 1, 2023, 5:55 PM MDT for Eagle County, Garfield County, Pitkin County, Colorado. It was in force for 74 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 1, 2023, 5:55 PM MDT (23:55 UTC)
Expired: Aug 1, 2023, 7:09 PM MDT
In force: 74 min
Issued by: NWS Grand Junction, CO
Area: Storm-based polygon
Flood severity: None

Counties Eagle County, CO, Garfield County, CO, Pitkin County, CO

The radar

The Grand Junction radar (KGJX), 101 km from the middle of the area, began a volume at 23:57 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

Grand Junction, CO (KGJT), launched 12:00Z, 11.9 hours before the alert went out and 121 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: 2 J/kg
Mixed-layer CIN: -237 J/kg
Mixed-layer LCL: 1649 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: -2 m²/s²
0-3 km storm-relative helicity: 140 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 flash flood 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 flash flood warning went out at Aug 1, 5:51 PM MDT, 4 minutes earlier.

Area forecast discussion, Aug 1, 5:51 PM MDT, 4 minutes before

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Hazardous weather outlook, Aug 1, 3:15 AM MDT, 14 hours 40 minutes before

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In the hours before

Special weather statement, Aug 1, 4:07 PM MDT, 1 hour 48 minutes before

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Special weather statement, Aug 1, 4:43 PM MDT, 1 hour 12 minutes before

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Special weather statement, Aug 1, 5:21 PM MDT, 34 minutes before

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Special weather statement, Aug 1, 5:34 PM MDT, 21 minutes before

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Local storm report, Aug 1, 5:48 PM MDT, 7 minutes before

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Local storm report, Aug 1, 5:50 PM MDT, 5 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
Jul 31, 6:24 PM MDT	Special Weather Statement	GJT	Moffat	36 min
Jul 31, 6:37 PM MDT	Special Weather Statement	GJT	Delta	23 min
Jul 31, 6:59 PM MDT	Special Weather Statement	GJT	Delta	31 min
Jul 31, 7:06 PM MDT	Special Weather Statement	GJT	Routt	24 min
Jul 31, 7:23 PM MDT	Special Weather Statement	GJT	Routt	37 min
Jul 31, 7:32 PM MDT	Special Weather Statement	GJT	Delta	28 min
Jul 31, 8:04 PM MDT	Areal Flood Advisory	GJT	Delta, Mesa	3 hr
Jul 31, 8:27 PM MDT	Special Weather Statement	GJT	Garfield	33 min
Jul 31, 8:44 PM MDT	Special Weather Statement	GJT	Mesa	31 min
Jul 31, 8:46 PM MDT	Special Weather Statement	GJT	Garfield	29 min
Jul 31, 8:59 PM MDT	Special Weather Statement	GJT		31 min
Jul 31, 9:06 PM MDT	Areal Flood Advisory	GJT	Garfield	3 hr
Jul 31, 9:20 PM MDT	Special Weather Statement	GJT	Garfield	25 min
Jul 31, 9:26 PM MDT	Special Weather Statement	GJT	Garfield	34 min
Aug 1, 12:13 PM MDT	Flash Flood Watch	GJT	Eagle, Garfield, Moffat, Pitkin, Rio Blanco, Routt	7 hr
Aug 1, 12:57 PM MDT	Areal Flood Advisory	GJT	Garfield	93 min
Aug 1, 2:23 PM MDT	Special Weather Statement	GJT		37 min
Aug 1, 2:42 PM MDT	Special Weather Statement	GJT	Routt	33 min
Aug 1, 2:53 PM MDT	Special Weather Statement	GJT	Rio Blanco	22 min
Aug 1, 3:25 PM MDT	Special Weather Statement	GJT	Mesa	35 min
Aug 1, 3:48 PM MDT	Special Weather Statement	GJT	Delta	27 min
Aug 1, 4:05 PM MDT	Areal Flood Advisory	GJT	Delta	55 min
Aug 1, 4:07 PM MDT	Special Weather Statement	GJT	Routt	38 min
Aug 1, 4:18 PM MDT	Areal Flood Advisory	GJT	Mesa	87 min
Aug 1, 4:43 PM MDT	Special Weather Statement	GJT	Routt	17 min
Aug 1, 5:19 PM MDT	Areal Flood Advisory	GJT	Eagle, Garfield, Pitkin	36 min
Aug 1, 5:21 PM MDT	Special Weather Statement	GJT	Garfield	24 min
Aug 1, 5:34 PM MDT	Special Weather Statement	GJT	Pitkin	11 min
Aug 1, 5:42 PM MDT	Areal Flood Advisory	GJT	Garfield, Mesa	86 min
Jul 31, 9:32 PM MDT	Special Weather Statement	GJT	Grand	28 min
Jul 31, 9:57 PM MDT	Special Weather Statement	GJT	Grand	33 min
Jul 31, 11:01 PM MDT	Special Weather Statement	GJT	Grand	29 min
Aug 1, 2:03 PM MDT	Special Weather Statement	GJT	Uintah	27 min

Nearby

Flash Flood Warnings in Colorado, 2023 Every flash flood warning in 2023

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.