Monsoon moisture continued to move northward across Arizona with strong to severe thunderstorms developing.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS FGZ wrote it up.
Monsoon moisture continued to move northward across Arizona with strong to severe thunderstorms developing.
The local office's own words before the first event, 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 the first event at Jul 10, 3:46 PM MST, 1 hour 15 minutes earlier.
Area Forecast Discussion National Weather Service Flagstaff AZ 345 PM MST Sat Jul 10 202 .SYNOPSIS...Hot weather continues this weekend, with chances of afternoon and evening showers and thunderstorms, primarily south of the I-40 corridor. More significant moisture looks to return next week, with greater chances for showers and thunderstorms across much of northern and central Arizona. && .DISCUSSION...Convection has fired off pretty much as expected, with the exception of a fairly active area that formed in central Navajo and Apache counties, that is now approaching the I-40 corridor. Activity should diminish and head into the lower deserts this evening, with clearing skies from the north. Somewhat quieter on Sunday as we lose some boundary layer moisture and remain warm aloft. This will be short-lived, as the doors are fully open to the monsoon next week. Expect active weather next week as we ramp into moderate/high monsoon levels. Flash flooding and severe hail will become more common each day. Heat peaks today, still around tomorrow, then next week will cool to more seasonable levels. && .AVIATION...For the 00Z package...Expect mainly VFR conditions for the 24 hour TAF forecast period. Sct SHRA/TSRA and ISOLD +TSRA producing brief MVFR along and south of the I-40 corridor through 03Z Sunday. Similar conditions redevelop again AFT 18Z-19Z Sunday. Sfc winds 5-15kts outside of storms. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Scattered showers and thunderstorms are expected again on Sunday, mainly south of the I-40 corridor. Activity will increase Monday, with lowering temperatures. Tuesday through Thursday...Expect an active pattern, with scattered to numerous showers and thunderstorms each day. As a result, expect cooler temperatures and generally light winds. && .FGZ WATCHES/WARNINGS/ADVISORIES... Excessive Heat Warning until 8 PM MST Saturday for AZZ037. Excessive Heat Warning until 8 PM MST Sunday for AZZ005-006. && PUBLIC...Peterson AVIATION...Peterson FIRE WEATHER...Peterson For Northern Arizona weather information visit weather.gov/flagstaff
Special Weather Statement National Weather Service Flagstaff AZ 136 PM MDT Sat Jul 10 2021 AZZ011-040-102000- Chuska Mountains and Defiance Plateau- Northeast Plateaus and Mesas South of Hwy 264- 136 PM MDT Sat Jul 10 2021 ...SIGNIFICANT WEATHER ADVISORY FOR A STRONG THUNDERSTORM OVER APACHE COUNTY AND THE NAVAJO NATION UNTIL 200 PM MDT... At 134 PM MDT, Doppler radar was tracking a strong thunderstorm over Wide Ruins moving south at 20 mph. Nickel size hail and winds in excess of 40 mph will be possible with this storm. Locations impacted include... Wide Ruins and parts of US Hwy 191 between Wide Ruins and Chambers. LAT...LON 3551 10957 3550 10939 3530 10935 3533 10966 TIME...MOT...LOC 1934Z 004DEG 17KT 3543 10948 NL
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
112 PM MST SAT JUL 10 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0707 PM HAIL 1 NW HEBER-OVERGAARD 34.43N 110.58W
07/09/2021 M1.00 INCH NAVAJO AZ PUBLIC
&&Special Weather Statement National Weather Service Flagstaff AZ 157 PM MST Sat Jul 10 2021 AZZ018-102130- Northern Gila County- 157 PM MST Sat Jul 10 2021 ...SIGNIFICANT WEATHER ADVISORY FOR A STRONG THUNDERSTORM IN GILA COUNTY INCLUDING AREAS NEAR CANYON DAY UNTIL 230 PM MST... At 156 PM MST, Doppler radar was tracking a strong thunderstorm near Fort Apache and Canyon Day, or 32 miles south of Show Low, moving west at 15 mph. Nickel size hail and winds in excess of 40 mph will be possible with this storm. Locations impacted include... Whiteriver, Fort Apache Reservation and Canyon Day. PRECAUTIONARY/PREPAREDNESS ACTIONS... 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 3380 11029 3386 11000 3367 11000 3364 11009 TIME...MOT...LOC 2056Z 077DEG 11KT 3377 11005 NL
Special Weather Statement
National Weather Service Flagstaff AZ
255 PM MST Sat Jul 10 2021
AZZ008-037-102245-
Yavapai County Valleys and Basins-Yavapai County Mountains-
255 PM MST Sat Jul 10 2021
...SIGNIFICANT WEATHER ADVISORY FOR STRONG THUNDERSTORMS IN YAVAPAI
COUNTY UNTIL 345 PM MST...
At 254 PM MST, Doppler radar was tracking strong thunderstorms along
a line extending from 6 miles west of Paulden to near Yavapai County
Fairgrounds. Movement was west at 15 mph.
Half inch hail and wind gusts up to 50 mph will be possible with
these storms.
Locations impacted include...
Chino Valley, Prescott Valley, Prescott, Prescott Airport, Williamson
Valley, Prescott Gateway Mall, Iron Springs, Yavapai Campground,
Downtown Prescott, Ponderosa Park, Indian Hill West Prescott, Oak
Knoll Village, Lynx Lake Dam, Prescott Valley Event Center and White
Spar Campground.
LAT...LON 3482 11278 3445 11247 3461 11225 3470 11241
3486 11256
TIME...MOT...LOC 2154Z 068DEG 15KT 3487 11258 3460 11232
NLThe Flagstaff radar (KFSX), 12 km away, was scanning. The volume nearest the first event began at 00:01 UTC.
1 tornado, 1 hail. Local standard time, as filed.
Photos of large ponderosa pine trees snapped off, funnel cloud, and radar signature supported reports of a tornado. Path Measured after official NWS storm survey.
One inch diameter hail fell 3 miles southeast of Forest Lakes (Social Media).
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Arizona in 2021Every state in 2021This day in weather historyThe tornado archive for Arizona, 2021Warnings in Arizona, July 2021
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 976915, 976912.