Alert archive / Colorado / Flash Flood Warnings in 2019

Flash Flood Warning 4, NWS Grand Junction, CO

July 26, 2019Delta County, Colorado

NWS Grand Junction, CO issued this flash flood warning at Jul 26, 2019, 7:00 PM MDT for Delta County, Colorado. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jul 26, 2019, 7:00 PM MDT (01:00 UTC)
Expired: Jul 26, 2019, 10:00 PM MDT
In force: 3 hr
Issued by: NWS Grand Junction, CO
Area: Storm-based polygon
Flood severity: None

County Delta County, CO

The radar

The Grand Junction radar (KGJX), 38 km from the middle of the area, began a volume at 01:04 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

Denver, CO (KDNR), launched 00:00Z, 1.0 hours before the alert went out and 414 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: 134 J/kg
Mixed-layer CIN: -2 J/kg
Mixed-layer LCL: 3097 m above ground
0-6 km bulk shear: 18 kt
0-1 km storm-relative helicity: -1 m²/s²
0-3 km storm-relative helicity: 35 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 Jul 26, 4:55 PM MDT, 2 hours 5 minutes earlier.

Area forecast discussion, Jul 26, 4:55 PM MDT, 2 hours 5 minutes before

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Hazardous weather outlook, Jul 26, 4:25 AM MDT, 14 hours 35 minutes before

Hazardous Weather Outlook
National Weather Service Grand Junction CO
425 AM MDT Fri Jul 26 2019

COZ001>014-017>023-UTZ022>025-027>029-271200-
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 Fri Jul 26 2019

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

.DAY ONE...Today and Tonight

Scattered to numerous thunderstorms are expected over the
high country with the southern ranges favored. Lightning, heavy
rain and gusty outflow winds up to 40 MPH are the main threats
through late this evening.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday

Thunderstorm coverage will peak on Saturday, before drier
conditions move in Sunday through Tuesday. Heavy rainfall rates
will remain a significant threat through Saturday. Thereafter,
there will be a decreasing trend in thunderstorm activity from
Sunday into early next week.

Monsoonal moisture will surge back over eastern Utah and western
Colorado by Wednesday, with showers and thunderstorms returning to
much of the region.

.SPOTTER INFORMATION STATEMENT...

Spotter activation is not expected today or tonight, however
spotters are encouraged to relay rainfall amounts or any observed
flooding to the National Weather Service in Grand Junction.

In the hours before

Special weather statement, Jul 26, 5:23 PM MDT, 1 hour 37 minutes before

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Special weather statement, Jul 26, 5:24 PM MDT, 1 hour 36 minutes before

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Special weather statement, Jul 26, 6:03 PM MDT, 57 minutes before

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Special weather statement, Jul 26, 6:28 PM MDT, 32 minutes before

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Special weather statement, Jul 26, 6:34 PM MDT, 26 minutes before

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Local storm report, Jul 26, 6:40 PM MDT, 20 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 26, 6:03 PM MDT	Special Weather Statement	GJT	Montrose	27 min
Jul 26, 6:15 PM MDT	Areal Flood Advisory	GJT	Mesa	3 hr
Jul 26, 6:28 PM MDT	Special Weather Statement	GJT	Montrose	32 min
Jul 26, 6:34 PM MDT	Special Weather Statement	GJT	Delta	26 min
Jul 26, 7:03 PM MDT	Special Weather Statement	GJT	Delta	27 min
Jul 27, 3:57 AM MDT	Flash Flood Watch	GJT	Archuleta, Delta, Dolores, Eagle, Garfield, Gunnison and 10 more	17 hr
Jul 27, 12:20 PM MDT	Areal Flood Advisory	GJT	Delta, Mesa	101 min
Jul 27, 12:34 PM MDT	Special Weather Statement	GJT	Montrose	26 min
Jul 27, 4:52 PM MDT	Special Weather Statement	GJT	Mesa	38 min

Nearby

Flash Flood Warnings in Colorado, 2019 Every flash flood 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.