A well-defined upper low over northern Arizona brought scattered strong morning thunderstorms to northeastern Arizona.
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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.
A well-defined upper low over northern Arizona brought scattered strong morning thunderstorms to northeastern Arizona.
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 Aug 28, 3:31 AM MST, 5 hours 19 minutes earlier.
Area Forecast Discussion National Weather Service Flagstaff AZ 331 AM MST SUN AUG 28 2016 .SYNOPSIS...Decreasing thunderstorm chances are forecast through mid- week. Monsoon moisture should return to northern Arizona by Thursday with thunderstorm chances increasing Thursday through the end of the week. && .DISCUSSION...A well-defined upper low is currently centered over northern Arizona this morning. The center of the low is forecast to pivot east through the day. Synoptic subsidence (per Q-vector analysis) on the back side of the low should keep convection to a minimum over Coconino, Yavapai, and Gila counties this afternoon. However, Navajo and Apache counties north of I-40 are forecast to see scattered to numerous thunderstorms this afternoon. Weak to marginal instability and shear parameters should keep any thunderstorms below severe limits. The aforementioned low is then forecast to slowly meander east into New Mexico Monday and continue to push east as high pressure builds into the southwestern US through Wednesday. Synoptic subsidence should keep convection to a minimum through Wednesday as a result. Said high pressure is then forecast to rotate east of Arizona by Thursday opening up Gulf of California moisture to the state. This monsoon pattern should continue through the end of the week, with dry southwesterly flow forecast to develop by Sunday, Sept. 4. && .AVIATION...For the 12Z package...VFR conditions will prevail across the majority of northern Arizona over the next 24 hours. The best chances for storms today will be over higher terrain in Navajo and Apache counties from 17Z Sun to 02Z Mon. Elsewhere, storms are expected to be more isolated with chances too low to be included in TAFs. Aviation discussion not updated for TAF amendments. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && PUBLIC...TM AVIATION...RR For Northern Arizona weather information visit weather.gov/flagstaff
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE FLAGSTAFF AZ 338 AM MST SUN AUG 28 2016 AZZ004>006-009>011-014-017-039-040-290430- KAIBAB PLATEAU-MARBLE AND GLEN CANYONS-GRAND CANYON COUNTRY- NORTHEAST PLATEAUS AND MESAS HWY 264 NORTHWARD-CHINLE VALLEY- CHUSKA MOUNTAINS AND DEFIANCE PLATEAU- LITTLE COLORADO RIVER VALLEY IN APACHE COUNTY-WHITE MOUNTAINS- BLACK MESA AREA-NORTHEAST PLATEAUS AND MESAS SOUTH OF HWY 264- 338 AM MST SUN AUG 28 2016 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTH CENTRAL ARIZONA AND NORTHEAST ARIZONA. .DAY ONE...TODAY AND TONIGHT SCATTERED SHOWERS AND THUNDERSTORMS ARE FORECAST TO DEVELOP PRIMARILY OVER THE HIGHER TERRAIN OF NAVAJO NATION THIS AFTERNOON. THE MAIN THREATS WILL BE DANGEROUS CLOUD TO GROUND LIGHTNING...SMALL HAIL...AND GUSTY WINDS. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY A DECREASE IN STORM COVERAGE IS FORECAST FOR MONDAY THROUGH WEDNESDAY. MOISTURE AND STORM CHANCES INCREASE AGAIN STARTING THURSDAY. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS TO THE NWS FLAGSTAFF OFFICE AT 1-888-745-1637. AZZ007-008-012-013-015-016-018-037-038-290430- COCONINO PLATEAU-YAVAPAI COUNTY MOUNTAINS- LITTLE COLORADO RIVER VALLEY IN COCONINO COUNTY- LITTLE COLORADO RIVER VALLEY IN NAVAJO COUNTY- WESTERN MOGOLLON RIM-EASTERN MOGOLLON RIM-NORTHERN GILA COUNTY- YAVAPAI COUNTY VALLEYS AND BASINS-OAK CREEK AND SYCAMORE CANYONS- 338 AM MST SUN AUG 28 2016 THIS HAZARDOUS WEATHER OUTLOOK IS FOR APACHE...COCONINO... NORTHERN GILA...NAVAJO...AND YAVAPAI COUNTIES IN NORTHERN ARIZONA. .DAY ONE...TODAY AND TONIGHT ISOLATED THUNDERSTORMS ARE FORECAST TO DEVELOP PRIMARILY ALONG THE MOGOLLON RIM AND BRADSHAW MOUNTAINS LATE THIS AFTERNOON. THE MAIN THREATS WILL BE CLOUD TO GROUND LIGHTNING...SMALL HAIL...AND GUSTY WINDS. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY A DECREASE IN STORM COVERAGE IS FORECAST FOR MONDAY THROUGH WEDNESDAY. MOISTURE AND STORM CHANCES INCREASE AGAIN STARTING THURSDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION WILL NOT BE NEEDED. TM
The Flagstaff radar (KFSX), 197 km away, was scanning. The volume nearest the first event began at 15:50 UTC.
1 funnel cloud. Local standard time, as filed.
A cold core funnel cloud was seen as far away as Gallup, New Mexico.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Arizona in 2016Every state in 2016This day in weather historyWarnings in Arizona, August 2016
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: 659410.