A thunderstorm produced heavy rain that caused flash flooding in Antelope Canyon.
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.
A thunderstorm produced heavy rain that caused flash flooding in Antelope Canyon.
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 18, 3:00 PM MST, 2 hours 41 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE FLAGSTAFF AZ 300 PM MST MON JUL 18 2011 .SYNOPSIS...EXPECT MODERATE MONSOON CONDITIONS THROUGH WEDNESDAY BEFORE ANOTHER DRYING TREND DEVELOPS FROM WEST TO EAST EARLY THURSDAY THROUGH FRIDAY. BY NEXT WEEKEND...MONSOON CONDITIONS WILL RAMP BACK UP ONCE AGAIN...WITH SHOWERS AND THUNDERSTORMS INCREASING AND PUSHING BACK WEST AND NORTH ACROSS THE REGION. && .DISCUSSION...AN ACTIVE DAY TODAY ACROSS NORTHERN AZ AS EXPECTED... AND LOOKS LIKE TUESDAY WILL BE ACTIVE AS WELL WITH PLENTY OF MOISTURE AND INSTABILITY REMAINING OVER THE NORTHLAND. THE DIFFERENCE TOMORROW COMPARED TO TODAY WILL BE THE MID LEVEL FLOW...WHICH WILL BE MORE FROM THE SW GIVEN THAT A SHORT WAVE TROUGH WILL BE MOVING ACROSS THE PAC NW AND NORTHERN ROCKIES. THUNDERSTORMS WILL INITIATE ONCE AGAIN ALONG THE MOGOLLON RIM UP TO THE KAIBAB PLATEAU...BUT WITH CELL MOTION TO THE NE AND MORE ACTIVITY ACROSS THE NE PART OF THE STATE UP TO THE 4 CORNERS. ON WEDNESDAY THE LONGWAVE TROUGH WILL BEGIN TO DEEPEN ACROSS THE WEST...BUT THE PUSH OF DRY AIR ACROSS NORTHERN AZ MAY HOLD OFF UNTIL WEDNESDAY NIGHT OR EVEN THURSDAY...AND AS SUCH WEDNESDAY COULD SEE DECENT COVERAGE OF AFTERNOON SHOWERS/THUNDERSTORMS...PARTICULARLY ACROSS OUR EAST AND SOUTHEAST ZONES. THURSDAY AND FRIDAY...DRIER AIR WILL SPREAD ACROSS NORTHERN AZ WITH THE BEST CHANCE FOR ANY SHOWERS AND STORMS ACROSS THE EASTERN RIM AND WHITE MOUNTAINS. OVER THE WEEKEND...THE RIDGE TO OUR EAST WILL SHIFT FROM THE MISSISSIPPI VALLEY WEST TO COLORADO/NEW MEXICO...SETTING THE STAGE FOR A RETURN TO A MORE TYPICAL MONSOON PATTERN. STILL KEEPING OUR EYES ON A POSSIBLE TROPICAL SYSTEM SOUTH OF BAJA...WHICH COULD TRIGGER A NORTHWARD MOISTURE SURGE UP INTO AZ LATE IN THE WEEKEND. && .AVIATION...FOR THE 00Z PACKAGE....STORMS WILL DECREASE IN COVERAGE AFT 03Z BUT ISOLATED ACTIVITY IS STILL POSSIBLE. EXPECT ERRATIC SURFACE WINDS WITH GUSTS TO 25-30 KTS AND MVFR TO LOCAL IFR CONDITIONS NEAR THE HEAVIER SHOWERS AND STORMS...SMALL HAIL POSSIBLE. FOR TUESDAY...EXPECT SCT SHOWERS AND THUNDERSTORM TO BEGIN DEVELOPING BY 17Z AND LASTING THROUGH AT LEAST 03Z WEDNESDAY. AVIATION DISCUSSION NOT UPDATED FOR AMENDMENTS. && PUBLIC..................PETRO AVIATION................TC FOR NORTHERN ARIZONA WEATHER INFORMATION VISIT WEATHER.GOV/FLAGSTAFF.
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE FLAGSTAFF AZ 1027 AM MST MON JUL 18 2011 AZZ004>018-037>040-190700- 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- 1027 AM MST MON JUL 18 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EAST CENTRAL ARIZONA...NORTH CENTRAL ARIZONA...NORTHEAST ARIZONA AND WEST CENTRAL ARIZONA. .DAY ONE...TODAY AND TONIGHT SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL DEVELOP THIS MORNING AND AFTERNOON. STORMS ARE EXPECTED TO FIRST DEVELOP AND WILL BE MOST NUMEROUS ALONG THE MOGOLLON RIM AND WHITE MOUNTAINS... AND WILL SPREAD NORTH TO THE KAIBAB PLATEAU. ELSEWHERE...STORMS WILL BE MORE ISOLATED TO SCATTERED...AND OCCUR LATER IN THE DAY. THE MAIN THREAT WITH ANY THUNDERSTORMS TODAY WILL BE CLOUD TO GROUND LIGHTNING AND HEAVY RAIN. PERSONS IN FLASH FLOOD PRONE AREAS SHOULD PAY CLOSE ATTENTION TO THE WEATHER TODAY. .DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY TYPICAL MONSOON SEASON SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE THROUGH THE MIDDLE OF THE WEEK. THEN...SOME DRIER AIR MAY MOVE INTO THE WESTERN AND NORTHERN PORTIONS OF THE STATE THURSDAY THROUGH SATURDAY. MONSOON MOISTURE WILL RETURN WITH SHOWERS AND THUNDERSTORMS INCREASING IN COVERAGE ONCE AGAIN BY LATE IN THE WEEKEND.
The Cedar City radar (KICX), 149 km away, was scanning. The volume nearest the first event began at 00:40 UTC.
1 flash flood. Local standard time, as filed.
Tuba City Police received a report that there was a high volume of water flowing through Antelope Canyon. The water flowed for 9 hours in this normally dry slot canyon. Five feet of sand washed out of the upper portion of the canyon.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Arizona in 2011Every state in 2011This day in weather historyWarnings in Arizona, July 2011
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: 335691.