Alert archive / Arizona / Severe Thunderstorm Warnings in 2018
Severe Thunderstorm Warning 164, NWS Flagstaff, AZ
NWS Flagstaff, AZ issued this severe thunderstorm warning at Sep 1, 2018, 7:53 AM MST for Coconino County, Navajo County, Arizona. It was in force for 37 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 1, 2018, 7:53 AM MST (14:53 UTC)
- Expired
- Sep 1, 2018, 8:30 AM MST
- In force
- 37 min
- Issued by
- NWS Flagstaff, AZ
- Area
- Storm-based polygon
- Hail
- 1.25 in
- Wind
- 60.0 mph
Counties Coconino County, AZ, Navajo County, AZ
The radar
The Flagstaff radar (KFSX), 117 km from the middle of the area, began a volume at 14:56 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 12:00Z, 2.9 hours before the alert went out and 81 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.
- Mixed-layer CAPE
- 1187 J/kg
- Mixed-layer CIN
- -32 J/kg
- Mixed-layer LCL
- 1079 m above ground
- 0-6 km bulk shear
- 30 kt
- 0-1 km storm-relative helicity
- 71 m²/s²
- 0-3 km storm-relative helicity
- 127 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 2.7
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 1, 4:09 AM MST, 3 hours 44 minutes earlier.
Area forecast discussion, Sep 1, 4:09 AM MST, 3 hours 44 minutes before
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</html>In the hours before
Special weather statement, Sep 1, 7:39 AM MST, 14 minutes before
Special Weather Statement
National Weather Service Flagstaff AZ
739 AM MST SAT SEP 1 2018
AZZ013-014-040-011515-
Little Colorado River Valley in Navajo County-
Little Colorado River Valley in Apache County-
Northeast Plateaus and Mesas South of Hwy 264-
739 AM MST SAT SEP 1 2018
...SIGNIFICANT WEATHER ADVISORY FOR APACHE AND NAVAJO COUNTIES UNTIL
815 AM MST...
At 738 AM MST, Doppler radar was tracking strong thunderstorms along
a line extending from Holbrook to 7 miles south of Woodruff to 7
miles west of Concho. Movement was east at 25 mph.
Nickel size hail and winds in excess of 40 mph will be possible with
these storms.
Locations impacted include...
Holbrook, St. Johns, Hunt, Sun Valley, Woodruff, Concho, Petrified
Forest National Park, Petrified Forest N.P. Visitors Center and
Petrified Forest N.P. Headquarters.
These storms may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.
LAT...LON 3511 10974 3467 10957 3442 10925 3438 10981
3467 11016 3501 11032
TIME...MOT...LOC 1438Z 269DEG 23KT 3491 11014 3467 11004 3451 10973
KDThe office that day
Everything else NWS Flagstaff, AZ issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 1, 5:49 AM MST | Severe Thunderstorm Warning | FGZ | Coconino, Yavapai | 26 min |
| Sep 1, 7:39 AM MST | Special Weather Statement | FGZ | 36 min | |
| Sep 1, 9:29 AM MST | Areal Flood Advisory | FGZ | Navajo | 3 hr |
| Sep 1, 10:18 AM MST | Severe Thunderstorm Warning | FGZ | Apache | 25 min |
| Sep 1, 1:59 PM MST | Special Weather Statement | FGZ | Coconino | 46 min |
| Sep 1, 2:30 PM MST | Severe Thunderstorm Warning | FGZ | Navajo | 45 min |
| Sep 1, 2:51 PM MST | Tornado Warning | FGZ | Navajo | 24 min |
| Sep 1, 3:09 PM MST | Severe Thunderstorm Warning | FGZ | Coconino | 51 min |
| Sep 1, 3:15 PM MST | Severe Thunderstorm Warning | FGZ | Coconino, Navajo | 45 min |
| Sep 1, 3:24 PM MST | Severe Thunderstorm Warning | FGZ | Coconino, Navajo | 36 min |
| Sep 1, 3:57 PM MST | Severe Thunderstorm Warning | FGZ | Coconino, Navajo | 48 min |
| Sep 1, 4:47 PM MST | Severe Thunderstorm Warning | FGZ | Coconino, Navajo | 43 min |
Nearby
Severe Thunderstorm Warnings in Arizona, 2018Every severe thunderstorm warning in 2018
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.