Alert archive / Arizona / Flash Flood Warnings in 2020

Flash Flood Warning 14, NWS Flagstaff, AZ

August 22, 2020Coconino County, Arizona

NWS Flagstaff, AZ issued this flash flood warning at Aug 22, 2020, 5:51 PM MST for Coconino County, Arizona. It was in force for 2 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 22, 2020, 5:51 PM MST (00:51 UTC)
Expired: Aug 22, 2020, 7:51 PM MST
In force: 2 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 00:53 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

Flgstf/Belemont, AZ (KFGZ), launched 00:00Z, 0.9 hours before the alert went out and 68 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 3008 m above ground
0-6 km bulk shear: 21 kt
0-1 km storm-relative helicity: 75 m²/s²
0-3 km storm-relative helicity: 200 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 22, 2:45 PM MST, 3 hours 6 minutes earlier.

Area forecast discussion, Aug 22, 2:45 PM MST, 3 hours 6 minutes before

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In the hours before

Special weather statement, Aug 22, 3:55 PM MST, 1 hour 56 minutes before

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Special weather statement, Aug 22, 4:04 PM MST, 1 hour 47 minutes before

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Special weather statement, Aug 22, 4:34 PM MST, 1 hour 17 minutes before

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Local storm report, Aug 22, 4:40 PM MST, 1 hour 11 minutes before

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Local storm report, Aug 22, 4:42 PM MST, 1 hour 9 minutes before

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Local storm report, Aug 22, 4:45 PM MST, 1 hour 6 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 22, 5:16 PM MST	Severe Thunderstorm Warning	FGZ	Coconino	44 min
Aug 22, 5:55 PM MST	Special Weather Statement	FGZ	Yavapai	35 min
Aug 22, 6:13 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	47 min
Aug 22, 7:01 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	44 min
Aug 22, 7:14 PM MST	Areal Flood Advisory	FGZ	Yavapai	3 hr
Aug 22, 8:08 PM MST	Special Weather Statement	FGZ		22 min
Aug 22, 10:53 PM MST	Special Weather Statement	FGZ		37 min
Aug 23, 12:11 AM MST	Severe Thunderstorm Warning	FGZ	Yavapai	23 min
Aug 23, 12:31 AM MST	Special Weather Statement	FGZ	Yavapai	29 min
Aug 23, 12:26 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	34 min
Aug 23, 12:35 PM MST	Areal Flood Advisory	FGZ	Yavapai	20 min
Aug 23, 12:54 PM MST	Flash Flood Warning Considerable damage threat	FGZ	Yavapai	5 hr
Aug 23, 1:43 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	32 min
Aug 23, 2:08 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	26 min
Aug 23, 2:10 PM MST	Areal Flood Advisory	FGZ	Yavapai	3 hr
Aug 23, 2:30 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	30 min
Aug 23, 2:51 PM MST	Special Weather Statement	FGZ		24 min
Aug 23, 3:19 PM MST	Severe Thunderstorm Warning	FGZ	Coconino	26 min
Aug 23, 3:48 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	27 min

Nearby

Flash Flood Warnings in Arizona, 2020 Every flash flood 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.