Alert archive / Arizona / Severe Thunderstorm Warnings in 2014

Severe Thunderstorm Warning 27, NWS Flagstaff, AZ

September 20, 2014Coconino County, Arizona

NWS Flagstaff, AZ issued this severe thunderstorm warning at Sep 20, 2014, 3:05 PM MST for Coconino County, Arizona. It was in force for 16 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: Sep 20, 2014, 3:05 PM MST (22:05 UTC)
Expired: Sep 20, 2014, 3:21 PM MST
In force: 16 min
Issued by: NWS Flagstaff, AZ
Area: Storm-based polygon

County Coconino County, AZ

The radar

The Flagstaff radar (KFSX), 150 km from the middle of the area, began a volume at 22:07 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

Phoenix, AZ (KPSR), launched 12:00Z, 10.1 hours before the alert went out and 268 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: 260 J/kg
Mixed-layer CIN: -231 J/kg
Mixed-layer LCL: 1746 m above ground
0-6 km bulk shear: 6 kt
0-1 km storm-relative helicity: -57 m²/s²
0-3 km storm-relative helicity: 19 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 severe thunderstorm 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 severe thunderstorm warning went out at Sep 20, 8:55 AM MST, 6 hours 10 minutes earlier.

Area forecast discussion, Sep 20, 8:55 AM MST, 6 hours 10 minutes before

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Hazardous weather outlook, Sep 20, 3:18 AM MST, 11 hours 47 minutes before

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In the hours before

Special weather statement, Sep 20, 2:58 PM MST, 7 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
Sep 19, 5:12 PM MST	Special Weather Statement	FGZ		33 min
Sep 19, 6:53 PM MST	Special Weather Statement	FGZ		37 min
Sep 20, 2:58 PM MST	Special Weather Statement	FGZ		47 min
Sep 20, 3:30 PM MST	Special Weather Statement	FGZ	Gila	30 min
Sep 20, 3:51 PM MST	Areal Flood Advisory	FGZ	Gila, Navajo	3 hr

Nearby

Severe Thunderstorm Warnings in Arizona, 2014 Every severe thunderstorm warning in 2014

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.