Alert archive / Arizona / Severe Thunderstorm Warnings in 2020
Severe Thunderstorm Warning 22, NWS Flagstaff, AZ
NWS Flagstaff, AZ issued this severe thunderstorm warning at Aug 20, 2020, 3:15 PM MST for Apache County, Gila County, Navajo County, Arizona. It was in force for 30 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
- Aug 20, 2020, 3:15 PM MST (22:15 UTC)
- Expired
- Aug 20, 2020, 3:45 PM MST
- In force
- 30 min
- Issued by
- NWS Flagstaff, AZ
- Area
- Storm-based polygon
- Hail
- 1.0 in
- Wind
- 60.0 mph
Counties Apache County, AZ, Gila County, AZ, Navajo County, AZ
The radar
The Flagstaff radar (KFSX), 96 km from the middle of the area, began a volume at 22:15 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, 10.3 hours before the alert went out and 228 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
- 900 J/kg
- Mixed-layer CIN
- -294 J/kg
- Mixed-layer LCL
- 3154 m above ground
- 0-6 km bulk shear
- 14 kt
- 0-1 km storm-relative helicity
- -2 m²/s²
- 0-3 km storm-relative helicity
- 23 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 Aug 20, 2:39 PM MST, 36 minutes earlier.
Area forecast discussion, Aug 20, 2:39 PM MST, 36 minutes before
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Special weather statement, Aug 20, 1:14 PM MST, 2 hours 1 minute before
Special Weather Statement National Weather Service Flagstaff AZ 114 PM MST Thu Aug 20 2020 AZZ016-018-202100- Northern Gila County-Eastern Mogollon Rim- 114 PM MST Thu Aug 20 2020 ...SIGNIFICANT WEATHER ADVISORY FOR GILA AND COCONINO COUNTIES UNTIL 200 PM MST... At 113 PM MST, Doppler radar was tracking a strong thunderstorm over Christopher Creek, or 8 miles west of Forest Lakes, moving southwest at 5 mph. Penny size hail and winds in excess of 30 mph will be possible with this storm. Locations impacted include... Hunter Creek, Christopher Creek, Forest Road 9350 Campground, Forest Road 169 Campground, Rim Campground, Spillway Campground, Christopher Creek Campground, Woods Canyon Lake Campground, Sharp Creek Campground, Forest Road 195 Campground, Mogollon Campground and Crook Campground. LAT...LON 3422 11095 3430 11107 3439 11096 3433 11087 TIME...MOT...LOC 2013Z 046DEG 6KT 3433 11096 McCollum
Special weather statement, Aug 20, 1:51 PM MST, 1 hour 24 minutes before
Special Weather Statement National Weather Service Flagstaff AZ 151 PM MST Thu Aug 20 2020 AZZ016-202115- Eastern Mogollon Rim- 151 PM MST Thu Aug 20 2020 ...SIGNIFICANT WEATHER ADVISORY FOR COCONINO COUNTY UNTIL 215 PM MST... At 150 PM MST, Doppler radar was tracking a strong thunderstorm 7 miles north of Christopher Creek, or 13 miles northwest of Forest Lakes, moving southwest 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 Coconino County. LAT...LON 3448 11101 3444 11095 3437 11101 3443 11109 TIME...MOT...LOC 2050Z 035DEG 5KT 3443 11102 McCollum
Special weather statement, Aug 20, 2:13 PM MST, 1 hour 2 minutes before
Special Weather Statement National Weather Service Flagstaff AZ 213 PM MST Thu Aug 20 2020 AZZ016-202145- Eastern Mogollon Rim- 213 PM MST Thu Aug 20 2020 ...SIGNIFICANT WEATHER ADVISORY FOR COCONINO COUNTY UNTIL 245 PM MST... At 211 PM MST, Doppler radar was tracking a strong thunderstorm near Starlight Pines, moving southwest at 5 mph. Penny size hail and winds in excess of 30 mph will be possible with this storm. Locations impacted include... Starlight Pines. LAT...LON 3464 11111 3455 11101 3446 11108 3458 11121 TIME...MOT...LOC 2111Z 036DEG 5KT 3457 11111 McCollum
Special weather statement, Aug 20, 3:07 PM MST, 8 minutes before
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</html>The office that day
Everything else NWS Flagstaff, AZ issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 19, 5:50 PM MST | Severe Thunderstorm Warning | FGZ | Yavapai | 25 min |
| Aug 20, 1:14 PM MST | Special Weather Statement | FGZ | 46 min | |
| Aug 20, 1:51 PM MST | Special Weather Statement | FGZ | 24 min | |
| Aug 20, 2:13 PM MST | Special Weather Statement | FGZ | 32 min | |
| Aug 20, 2:33 PM MST | Severe Thunderstorm Warning | FGZ | Gila | 27 min |
| Aug 20, 3:07 PM MST | Special Weather Statement | FGZ | 23 min | |
| Aug 20, 3:21 PM MST | Severe Thunderstorm Warning | FGZ | Gila | 24 min |
| Aug 20, 4:16 PM MST | Special Weather Statement | FGZ | 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.