Deep monsoon moisture continued to move northward over Arizona with scattered heavy rain.
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 continued to move northward over Arizona with scattered heavy rain.
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 4, 10:05 AM MST, 2 hours 45 minutes earlier.
Area Forecast Discussion National Weather Service Flagstaff AZ 1005 AM MST THU AUG 04 2016 .SYNOPSIS...Expect frequent and widespread storm activity today. Deep moisture will mean that the stronger storms will contain torrential rainfall. A slow drying trend begins Friday, lasting through the weekend and into next week. && .DISCUSSION...Morning satellite imagery reveals a MCV near the four corners and a weak s/wv moving north through western Arizona. This s/wv is moving with the increasing southwesterly flow that will be developing over the west in the next few days. A large amount of debris cloud exists over the state, as well as a rain cooled boundary layer and a moist adiabatic airmass to 400mb. None of this bodes well for the development of strong or widespread convection today. However, the presence of the two mesoscale features mentioned above and the slight increase in shear will partially offset the inhibiting factors. The current forecast may be a bit high and early on the pops and we may need to consider more nocturnal action tonight. We may make a few tweaks to address this, but the overall picture is largely in good shape this morning. The Flash Flood Watch continues until 6PM this evening. && .AVIATION...For the 18Z package...SCT-NMRS SHRA/TSRA will develop today with ISOLD-SCT MVFR/IFR conditions. Storms will decrease in coverage aft 04z...with only ISOLD -SHRA/TSRA expected overnight. Aviation discussion not updated for TAF amendments. && .FGZ WATCHES/WARNINGS/ADVISORIES...Flash Flood Watch until 6PM MST AZZ004>018-037>040. && PUBLIC...Peterson AVIATION...MAS For Northern Arizona weather information visit weather.gov/flagstaff
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE FLAGSTAFF AZ 312 AM MST THU AUG 4 2016 AZZ004>018-037>040-050400- KAIBAB PLATEAU-MARBLE AND GLEN CANYONS-GRAND CANYON COUNTRY- COCONINO PLATEAU-YAVAPAI COUNTY MOUNTAINS- NORTHEAST PLATEAUS AND MESAS HWY 264 NORTHWARD-CHINLE VALLEY- CHUSKA MOUNTAINS AND DEFIANCE PLATEAU- LITTLE COLORADO RIVER VALLEY IN COCONINO COUNTY- LITTLE COLORADO RIVER VALLEY IN NAVAJO COUNTY- LITTLE COLORADO RIVER VALLEY IN APACHE COUNTY- WESTERN MOGOLLON RIM-EASTERN MOGOLLON RIM-WHITE MOUNTAINS- NORTHERN GILA COUNTY-YAVAPAI COUNTY VALLEYS AND BASINS- OAK CREEK AND SYCAMORE CANYONS-BLACK MESA AREA- NORTHEAST PLATEAUS AND MESAS SOUTH OF HWY 264- 312 AM MST THU AUG 4 2016 THIS HAZARDOUS WEATHER OUTLOOK IS FOR APACHE...COCONINO... NORTHERN GILA...NAVAJO...AND YAVAPAI COUNTIES IN NORTHERN ARIZONA. .DAY ONE...TODAY AND TONIGHT DEEP MONSOON MOISTURE WILL LEAD TO FREQUENT AND WIDESPREAD SHOWER AND THUNDERSTORM ACTIVITY TODAY. A FLASH FLOOD WATCH IS IN EFFECT FOR ALL OF APACHE, COCONINO, NORTHERN GILA, NAVAJO AND YAVAPAI COUNTIES THROUGH 6 PM THIS AFTERNOON. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY FREQUENT SHOWER AND THUNDERSTORM ACTIVITY IS FORECAST ON FRIDAY. EXPECT A DRYING TREND OVER THE WEEKEND AND EARLY NEXT WEEK. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.
PRELIMINARY LOCAL STORM REPORT...CORRECTED
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
917 AM MST THU AUG 04 2016
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1030 PM FLASH FLOOD 1 SSW WIDE RUINS 35.41N 109.50W
08/03/2016 APACHE AZ DEPT OF HIGHWAYS
DEBRIS FLOW WAS REPORTED ACROSS HWY 191 AT MM
389-390... ROAD WAS TEMPORARILY CLOSED. RADAR ESTIMATED
1 INCH OF RAIN IN LESS THAN 60 MINUTES.
&&
CORRECTED LOCATION...EVENT...REMARKS
EVENT NUMBER FGZ1600227
TMPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE FLAGSTAFF AZ
1109 AM MST THU AUG 4 2016
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0715 PM FLASH FLOOD 17 WNW LEES FERRY 36.99N 111.86W
08/03/2016 COCONINO AZ OTHER FEDERAL
ESTIMATED PARIA RIVER RISE NEAR THE AZ/UT
BORDER GREATER THAN 2 FEET IN 15-30 MINUTES.
USGS PARIA RIVER GAGE AT HWY 89 IN UTAH
REPORTED ~ 1.4 FT. RISE IN 15 MINUTES AT 6PM
MST. USGS PARIA RIVER GAGE AT LEES FERRY
REPORTED ~ 1.1 FT. RISE IN 30 MINUTES AT
9:45PM MST. EXTRAPOLATING THE FLOOD WAVE
VELOCITY AND THE MUCH NARROWER CHANNEL NEAR
THE AZ/UT BORDER, IT CAN BE INFERRED A RISE
OF GREATER THAN 2 FEET WAS OBSERVED ALONG
THE PARIA RIVER NEAR THE AZ/UT BORDER.
&&
TMThe Flagstaff radar (KFSX), 110 km away, was scanning. The volume nearest the first event began at 19:51 UTC.
3 flash flood, 1 heavy rain. Local standard time, as filed.
A trained spotter in Prescott Valley reported 1.19 inches of rain in 35 minutes.
The Hassayampa River rose about 8 feet and was flowing rapidly. It is normally dry.
The Big Bug Creek rose an estimated 4 feet.
The observed rise in the Paria River gauge at Highway 89 (in Utah) was around 745 PM MST on August 4th. The crest reached the Lees Ferry gauge at around 415 AM on August 5th. Flash Flood levels in excess of 5 feet were estimated to have been in the Arizona section of the Paria River from 11 PM on August 4th through 7 AM on August 5th before entering the Colorado River.
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: 658378, 658416, 658791, 658797.