Alert archive / Arizona / Severe Thunderstorm Warnings in 2020
Severe Thunderstorm Warning 6, NWS Flagstaff, AZ
NWS Flagstaff, AZ issued this severe thunderstorm warning at Jul 23, 2020, 2:44 PM MST for Coconino County, Yavapai County, Arizona. It was in force for 31 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
- Jul 23, 2020, 2:44 PM MST (21:44 UTC)
- Expired
- Jul 23, 2020, 3:15 PM MST
- In force
- 31 min
- Issued by
- NWS Flagstaff, AZ
- Area
- Storm-based polygon
- Hail
- 1.0 in
- Wind
- 50.0 mph
Counties Coconino County, AZ, Yavapai County, AZ
The radar
The Flagstaff radar (KFSX), 113 km from the middle of the area, began a volume at 21:44 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, 9.7 hours before the alert went out and 33 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
- 391 J/kg
- Mixed-layer CIN
- -44 J/kg
- Mixed-layer LCL
- 1401 m above ground
- 0-6 km bulk shear
- 31 kt
- 0-1 km storm-relative helicity
- 49 m²/s²
- 0-3 km storm-relative helicity
- 79 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
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 Jul 23, 2:33 PM MST, 11 minutes earlier.
Area forecast discussion, Jul 23, 2:33 PM MST, 11 minutes before
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</html>In the hours before
Special weather statement, Jul 23, 11:46 AM MST, 2 hours 58 minutes before
Special Weather Statement National Weather Service Flagstaff AZ 1146 AM MST Thu Jul 23 2020 AZZ004-006-007-012-231930- Kaibab Plateau-Little Colorado River Valley in Coconino County-Coconino Plateau-Grand Canyon Country- 1146 AM MST Thu Jul 23 2020 ...SIGNIFICANT WEATHER ADVISORY NEAR THE GRAND CANYON IN COCONINO COUNTY UNTIL 1230 PM MST/130 PM MDT/... At 1145 AM MST/1245 PM MDT/, Doppler radar was tracking a strong thunderstorm near the east entrance of the Grand Canyon, moving northeast at 25 mph. Half inch hail and winds in excess of 30 mph will be possible with this storm. Locations impacted include... Desert View at Grand Canyon, Moran Point At Grand Canyon and Cape Royal At Grand Canyon. PRECAUTIONARY/PREPAREDNESS ACTIONS... Torrential rainfall is also occurring with this storm, and may lead to localized flooding. Do not drive your vehicle through flooded roadways. Frequent cloud to ground lightning is occurring with this storm. Lightning can strike 10 miles away from a thunderstorm. Seek a safe shelter inside a building or vehicle. && LAT...LON 3581 11184 3594 11199 3625 11193 3609 11140 TIME...MOT...LOC 1845Z 225DEG 21KT 3594 11185 TPS
Special weather statement, Jul 23, 11:59 AM MST, 2 hours 45 minutes before
Special Weather Statement National Weather Service Flagstaff AZ 1159 AM MST Thu Jul 23 2020 AZZ004-005-231945- Kaibab Plateau-Marble and Glen Canyons- 1159 AM MST Thu Jul 23 2020 ...SIGNIFICANT WEATHER ADVISORY NORTHEAST OF JACOB LAKE IN COCONINO COUNTY UNTIL 1245 PM MST... At 1158 AM MST, Doppler radar was tracking a strong thunderstorm 8 miles northeast of Jacob Lake, or 24 miles southeast of Kanab, moving north at 25 mph. Penny size hail and winds in excess of 30 mph will be possible with this storm. This storm will remain over mainly rural areas of Coconino County. PRECAUTIONARY/PREPAREDNESS ACTIONS... Torrential rainfall is also occurring with this storm, and may lead to localized flooding. Do not drive your vehicle through flooded roadways. Frequent cloud to ground lightning is occurring with this storm. Lightning can strike 10 miles away from a thunderstorm. Seek a safe shelter inside a building or vehicle. && LAT...LON 3700 11201 3675 11203 3674 11226 3700 11231 TIME...MOT...LOC 1858Z 177DEG 21KT 3682 11216 TPS
Local storm report, Jul 23, 12:16 PM MST, 2 hours 28 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
1216 PM MST THU JUL 23 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1215 PM HEAVY RAIN 5 WNW VERNON 34.28N 109.78W
07/23/2020 M1.31 INCH APACHE AZ TRAINED SPOTTER
&&
MCTSpecial weather statement, Jul 23, 1:07 PM MST, 1 hour 37 minutes before
Special Weather Statement National Weather Service Flagstaff AZ 107 PM MST Thu Jul 23 2020 AZZ008-037-232030- Yavapai County Valleys and Basins-Yavapai County Mountains- 107 PM MST Thu Jul 23 2020 ...SIGNIFICANT WEATHER ADVISORY NORTH OF PRESCOTT VALLEY IN YAVAPAI COUNTY UNTIL 130 PM MST... At 107 PM MST, Doppler radar was tracking a strong thunderstorm near Yavapai County Fairgrounds, or 9 miles east of Chino Valley, moving north at 5 mph. Penny size hail and winds in excess of 30 mph will be possible with this storm. This storm will remain over mainly rural areas of Yavapai County. PRECAUTIONARY/PREPAREDNESS ACTIONS... Torrential rainfall is also occurring with this storm, and may lead to localized flooding. Do not drive your vehicle through flooded roadways. Frequent cloud to ground lightning is occurring with this storm. Lightning can strike 10 miles away from a thunderstorm. Seek a safe shelter inside a building or vehicle. && LAT...LON 3467 11222 3470 11238 3485 11235 3481 11214 TIME...MOT...LOC 2007Z 192DEG 4KT 3472 11230 TPS
Special weather statement, Jul 23, 1:35 PM MST, 1 hour 9 minutes before
Special Weather Statement National Weather Service Flagstaff AZ 135 PM MST Thu Jul 23 2020 AZZ004-005-009-232115- Kaibab Plateau-Marble and Glen Canyons-Northeast Plateaus and Mesas Hwy 264 Northward- 135 PM MST Thu Jul 23 2020 ...SIGNIFICANT WEATHER ADVISORY NEAR MARBLE CANYON AND LEES FERRY IN COCONINO COUNTY UNTIL 215 PM MST/315 PM MDT/... At 134 PM MST/234 PM MDT/, Doppler radar was tracking a strong thunderstorm over Marble Canyon, or 13 miles southwest of Page, moving north at 25 mph. Nickel size hail and winds in excess of 40 mph will be possible with this storm. Locations impacted include... Lees Ferry, Wahweap and Marble Canyon. PRECAUTIONARY/PREPAREDNESS ACTIONS... Torrential rainfall is also occurring with this storm, and may lead to localized flooding. Do not drive your vehicle through flooded roadways. Frequent cloud to ground lightning is occurring with this storm. Lightning can strike 10 miles away from a thunderstorm. Seek a safe shelter inside a building or vehicle. && LAT...LON 3700 11147 3670 11152 3670 11173 3700 11179 TIME...MOT...LOC 2034Z 179DEG 20KT 3678 11163 TPS
Local storm report, Jul 23, 1:58 PM MST, 46 minutes before
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
158 PM MST THU JUL 23 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0157 PM HEAVY RAIN VERNON 34.25N 109.69W
07/23/2020 M2.20 INCH APACHE AZ PUBLIC
MEMBER OF THE PUBLIC REPORTED 2.20 INCHES OF
RAINFALL IN JUST OVER AN HOUR EARLY THIS
AFTERNOON.
&&
TPSThe office that day
Everything else NWS Flagstaff, AZ issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 22, 5:11 PM MST | Flash Flood Warning | FGZ | Gila, Yavapai | 3 hr |
| Jul 23, 10:31 AM MST | Special Weather Statement | FGZ | 29 min | |
| Jul 23, 10:56 AM MST | Severe Thunderstorm Warning | FGZ | Coconino | 28 min |
| Jul 23, 11:46 AM MST | Special Weather Statement | FGZ | Coconino | 44 min |
| Jul 23, 11:53 AM MST | Areal Flood Advisory | FGZ | Apache | 2 hr |
| Jul 23, 12:59 PM MST | Areal Flood Advisory | FGZ | Apache, Navajo | 3 hr |
| Jul 23, 1:07 PM MST | Special Weather Statement | FGZ | Yavapai | 23 min |
| Jul 23, 1:46 PM MST | Flash Flood Warning | FGZ | Coconino | 3 hr |
| Jul 23, 2:16 PM MST | Flash Flood Warning | FGZ | Yavapai | 3 hr |
| Jul 23, 4:46 PM MST | Special Weather Statement | FGZ | Yavapai | 29 min |
Nearby
Severe Thunderstorm Warnings in Arizona, 2020Every severe thunderstorm 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.