Alert archive / Arizona / Severe Thunderstorm Warnings in 2019

Severe Thunderstorm Warning 53, NWS Flagstaff, AZ

September 23, 2019Gila County, Navajo County, Arizona

NWS Flagstaff, AZ issued this severe thunderstorm warning at Sep 23, 2019, 4:31 PM MST for Gila County, Navajo County, Arizona. It was in force for 29 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 23, 2019, 4:31 PM MST (23:31 UTC)
Expired: Sep 23, 2019, 5:00 PM MST
In force: 29 min
Issued by: NWS Flagstaff, AZ
Area: Storm-based polygon
Tornado: Possible
Hail: 1.0 in
Wind: 60.0 mph

Counties Gila County, AZ, Navajo County, AZ

The radar

The Flagstaff radar (KFSX), 58 km from the middle of the area, began a volume at 23:32 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Sep 23, 9:52 AM MST	Severe Thunderstorm Watch	SPC	10 hr

The nearest sounding before it

Phoenix, AZ (KPSR), launched 12:00Z, 11.5 hours before the alert went out and 183 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: 843 J/kg
Mixed-layer CIN: -53 J/kg
Mixed-layer LCL: 1085 m above ground
0-6 km bulk shear: 44 kt
0-1 km storm-relative helicity: 65 m²/s²
0-3 km storm-relative helicity: 119 m²/s²
Significant tornado parameter: 0.4
Supercell composite: 2.8

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 23, 3:29 PM MST, 1 hour 2 minutes earlier.

Area forecast discussion, Sep 23, 3:29 PM MST, 1 hour 2 minutes before

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In the hours before

Local storm report, Sep 23, 11:22 AM MST, 5 hours 9 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
1122 AM MST MON SEP 23 2019

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1121 AM     HEAVY RAIN       5 NW TAYLOR             34.50N 110.17W
09/23/2019  M1.78 INCH       NAVAJO             AZ   COCORAHS

            1.78 INCHES OF RAIN MEASURED IN SNOWFLAKE.
            GROUND IS SATURATED. SOME MINOR FLOODING.

&&

TPS

Special weather statement, Sep 23, 12:15 PM MST, 4 hours 16 minutes before

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Local storm report, Sep 23, 12:21 PM MST, 4 hours 10 minutes before

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Special weather statement, Sep 23, 3:21 PM MST, 1 hour 10 minutes before

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      <h1 id="headline">This service is currently unavailable.</h1>
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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 23, 3:19 AM MST	Flash Flood Watch	FGZ	Coconino, Gila, Yavapai	24 hr
Sep 23, 8:23 AM MST	Special Weather Statement	FGZ	Yavapai	22 min
Sep 23, 8:45 AM MST	Flash Flood Warning	FGZ	Yavapai	4 hr
Sep 23, 9:27 AM MST	Areal Flood Advisory	FGZ	Apache, Navajo	3 hr
Sep 23, 12:09 PM MST	Flash Flood Warning	FGZ	Yavapai	5 hr
Sep 23, 12:15 PM MST	Special Weather Statement	FGZ		15 min
Sep 23, 12:37 PM MST	Severe Thunderstorm Warning	FGZ	Yavapai	23 min
Sep 23, 2:37 PM MST	Areal Flood Advisory	FGZ	Gila	33 min
Sep 23, 3:08 PM MST	Flash Flood Warning	FGZ	Gila	5 hr
Sep 23, 3:21 PM MST	Special Weather Statement	FGZ	Gila	39 min

Nearby

Severe Thunderstorm Warnings in Arizona, 2019 Every severe thunderstorm 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.