Deep monsoon moisture over northern Arizona and an area of low pressure moving over the area from the east brought more thunderstorms with heavy rain, flooding, and at least one funnel cloud. A mesoscale convective complex formed late in the day and kept thunderstorms going through the night and into the morning of July 25.
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.
Deep monsoon moisture over northern Arizona and an area of low pressure moving over the area from the east brought more thunderstorms with heavy rain, flooding, and at least one funnel cloud. A mesoscale convective complex formed late in the day and kept thunderstorms going through the night and into the morning of July 25.
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 23, 2:00 PM MST, 3 hours earlier.
Area Forecast Discussion National Weather Service Flagstaff AZ 200 PM MST Fri Jul 23 2021 .SYNOPSIS...Continuous rounds of scattered to widespread showers and thunderstorms can be expected through much of the weekend. As a result, the threat of flash flooding as well as an isolated strong to severe storm will remain. Storm coverage begins to decrease early next week, becoming more isolated to scattered. && .DISCUSSION...Widespread showers and thunderstorms will continue over much of northern Arizona this afternoon. Flash flooding from heavy rainfall is expected to be the primary threats with these storms. However, with some destabilization occurring this afternoon, a few isolated strong to severe thunderstorms will be possible this afternoon and into the early evening hours. An inverted trough over western Texas/New Mexico will continue to propagate westward into Arizona this weekend. With significant monsoonal moisture in place over much of Arizona, scattered to widespread showers and thunderstorms are expected to continue through much of the weekend. Significant flash flood threat is expected to continue through the weekend over much of northern Arizona, as a result, the Flash Flood Watch has been extended into Sunday evening. With the increased synoptic-scale lift from the approaching wave, nocturnal showers and thunderstorms are expected each night through Sunday. Latest hi-res guidance has an MCS developing this evening over eastern Arizona and pushing westward across the state overnight resulting from the increase dynamic support. Saturday, with the trough moving westward across the state, the greatest lift moves southeastward. Greatest potential for flash flooding will then be for areas along and southwest of the Mogollon Rim. Uncertainty still exists in exactly where the greatest force will be in place on Sunday to support heavier rainfall, but latest guidance continues the south and westward shift. For the start of next week, with Arizona now on the backside of the trough, moisture looks to decrease slightly. As a result, more isolated to scattered coverage is expected for the upcoming week. Temperatures are expected to remain cool through the weekend as with the trough in place over Arizona. As it drifts west and ejects into the Pacific early next week, temperatures begin to warm slightly as heights begin to rise once again. Background winds are also expected to remain light through the forecast period. && .AVIATION...For the 00Z package...MVFR conditions are possible through the TAF period with scattered to widespread showers and thunderstorms expected. Brief IFR conditions will be possible in some of the heavier showers. Gusty and erratic winds possible near thunderstorms, with winds remaining light otherwise. Aviation discussion not updated for TAF amendments. && .FIRE WEATHER...Significant flash flood potential exists through Sunday night. Scattered to numerous showers and thunderstorms are expected each afternoon this weekend, with storms also continuing into the overnight hours. Widespread wetting rains are likely with embedded areas of heavy rain. Storm coverage begins to decrease for the first part of next week. && .FGZ WATCHES/WARNINGS/ADVISORIES... Flash Flood Watch through Sunday evening FOR AZZ006>008-011>018- 037-038-040. && PUBLIC...Humphreys AVIATION...Humphreys FIRE WEATHER...Humphreys For Northern Arizona weather information visit weather.gov/flagstaff
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
340 PM MST FRI JUL 23 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0300 PM FLASH FLOOD 1 SSW PRESCOTT VALLEY 34.59N 112.33W
07/23/2021 YAVAPAI AZ PUBLIC
ROAD WASHED OUT DUE TO FLOODING.
&&
MDSpecial Weather Statement National Weather Service Flagstaff AZ 443 PM MDT Fri Jul 23 2021 AZZ013-040-232330- Little Colorado River Valley in Navajo County- Northeast Plateaus and Mesas South of Hwy 264- 443 PM MDT Fri Jul 23 2021 ...SIGNIFICANT WEATHER ADVISORY FOR NAVAJO COUNTY ALONG HIGHWAY 77 SOUTHEAST OF DILKON UNTIL 530 PM MDT/430 PM MST/... At 442 PM MDT/342 PM MST/, Doppler radar was tracking a strong thunderstorm 8 miles south of Indian Wells, or 37 miles south of Keams Canyon, moving south at 25 mph. Penny size hail and wind gusts up to 50 mph will be possible with this storm. Locations impacted include... Petrified Forest National Park. 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. && LAT...LON 3531 11030 3537 10995 3504 10985 3498 11029 TIME...MOT...LOC 2242Z 357DEG 21KT 3528 11010 JJ
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
354 PM MST FRI JUL 23 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0334 PM FLASH FLOOD 1 ENE COTTONWOOD 34.74N 112.01W
07/23/2021 YAVAPAI AZ PUBLIC
STREET FLOODING WITH WATER FLOWING OVER
ROAD.
&&
MDPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
428 PM MST FRI JUL 23 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0412 PM HAIL 2 NW SHOW LOW 34.26N 110.07W
07/23/2021 U0.50 INCH NAVAJO AZ PUBLIC
REPORT FROM MPING: HALF-INCH (0.50 IN.).
&&
MDPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
455 PM MST FRI JUL 23 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0420 PM FLASH FLOOD 1 S PRESCOTT VALLEY 34.59N 112.32W
07/23/2021 YAVAPAI AZ PUBLIC
ROADWAY UNDERWATER DUE TO FLOODING.
&&
MDPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
500 PM MST FRI JUL 23 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0355 PM HEAVY RAIN 2 NNW PAGE SPRINGS 34.80N 111.90W
07/23/2021 E0.85 INCH YAVAPAI AZ PUBLIC
0.85 INCHES OF RAIN IN ABOUT 30 MINUTES FROM
325 PM TO 355 PM.
&&
MASThe Flagstaff radar (KFSX), 118 km away, was scanning. The volume nearest the first event began at 00:01 UTC.
10 flash flood, 1 heavy rain, 1 funnel cloud. Local standard time, as filed.
A trained spotter 8 miles north of Vernon measured 2.80 inches of rain fall from Friday evening to Saturday morning. There was standing water on the property.
A funnel cloud was filmed for about 10 minutes 6 miles east of Dewey-Humboldt.
Water was flowing through a yard south-southeast of Concho.
The Agua Fria river gauge near Dewey-Humboldt measured a 6.5 foot rise around 1800 on July 24. The river gauge near Cordes Junction reported a 6.7 foot rise around 240 AM on July 25..
McClaws Road was close in Holbrooke due to the flash flooding of the Little Colorado River.
Flash flooding was reported along Navajo Route 4 west of Pi on Rodeo. The flood water was 6-12 inches deep.
A flash flood in The Little Colorado River covered the Highway 191 bridge in St Johns and made it impassable.
Minor street flooding with some garages flooded in Wildwood Hills Mobile Home Park area of west Flagstaff.
Flash flooding covered the roads (including Highway 160) with water, mud, and rocks near Tonalea and Cow Springs.
Flood waters swept a vehicle away in a low water crossing on Camino Real near Rocky Knolls Road. The flood water was estimated to be 8 feet deep. The body of the driver was found several days later at the confluence with the Verde River.
Some roads in Cottonwood were impassable with flowing water.
River Valley Road and Herold Ranch Road on the southeast side of Flagstaff were flooded and impassable.
As the offices recorded each death: direct deaths were caused by the weather itself, indirect ones by something it set in motion.
| Event | Date | Age | Sex | Where | Kind |
|---|---|---|---|---|---|
| Flash Flood, Yavapai | 2021-07-24 | 16 | Female | Vehicle/Towed Trailer | Direct |
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Arizona in 2021Every state in 2021This day in weather historyWarnings 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: 979248, 979249, 979250, 979264, 979267, 979254, 979265, 979251, 979266, 979440, 979252, 979256.