Alert archive / Arizona / Flash Flood Warnings in 2024

Flash Flood Warning 63, NWS Flagstaff, AZ

August 11, 2024Coconino County, Arizona

NWS Flagstaff, AZ issued this flash flood warning at Aug 11, 2024, 4:34 PM MST for Coconino County, Arizona. 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: Aug 11, 2024, 4:34 PM MST (23:34 UTC)
Expired: Aug 11, 2024, 7:30 PM MST
In force: 3 hr
Issued by: NWS Flagstaff, AZ
Area: Storm-based polygon
Damage threat: Considerable
Flood severity: None

County Coconino County, AZ

The radar

The Flagstaff radar (KFSX), 150 km from the middle of the area, began a volume at 23:36 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

Las Vegas, NV (KVEF), launched 12:00Z, 11.6 hours before the alert went out and 344 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: 626 J/kg
Mixed-layer CIN: -194 J/kg
Mixed-layer LCL: 2386 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: 21 m²/s²
0-3 km storm-relative helicity: -13 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 Flagstaff, AZ wrote its last area forecast discussion before this flash flood warning went out at Aug 11, 4:20 PM MST, 14 minutes earlier.

Area forecast discussion, Aug 11, 4:20 PM MST, 14 minutes before

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In the hours before

Local storm report, Aug 11, 11:13 AM MST, 5 hours 21 minutes before

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Special weather statement, Aug 11, 12:32 PM MST, 4 hours 2 minutes before

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Special weather statement, Aug 11, 1:12 PM MST, 3 hours 22 minutes before

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Special weather statement, Aug 11, 1:17 PM MST, 3 hours 17 minutes before

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Special weather statement, Aug 11, 2:11 PM MST, 2 hours 23 minutes before

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Local storm report, Aug 11, 3:10 PM MST, 1 hour 24 minutes before

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The office that day

Everything else NWS Flagstaff, AZ issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 10, 5:23 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino	8 hr
Aug 10, 5:56 PM MST	Special Weather Statement	FGZ		49 min
Aug 10, 6:21 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Yavapai	3 hr
Aug 10, 6:37 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino, Yavapai	3 hr
Aug 10, 7:17 PM MST	Severe Thunderstorm Warning	FGZ	Gila, Yavapai	13 min
Aug 10, 7:28 PM MST	Tornado Warning	FGZ	Yavapai	17 min
Aug 10, 7:46 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	11 min
Aug 10, 8:05 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	27 min
Aug 11, 12:32 PM MST	Special Weather Statement	FGZ	Coconino	28 min
Aug 11, 12:36 PM MST	Severe Thunderstorm Warning	FGZ	Coconino	24 min
Aug 11, 1:12 PM MST	Special Weather Statement	FGZ		33 min
Aug 11, 1:17 PM MST	Special Weather Statement	FGZ	Coconino	28 min
Aug 11, 2:04 PM MST	Severe Thunderstorm Warning	FGZ	Coconino	26 min
Aug 11, 2:11 PM MST	Special Weather Statement	FGZ	Coconino	34 min
Aug 11, 2:19 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Coconino	4 hr
Aug 11, 2:35 PM MST	Severe Thunderstorm Warning	FGZ	Coconino, Navajo	40 min

Nearby

Flash Flood Warnings in Arizona, 2024 Every flash flood warning in 2024

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.