A thunderstorm produced heavy rain around Cottonwood.
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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 thunderstorm produced heavy rain around Cottonwood.
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 Sep 12, 2:55 PM MST, 1 hour 50 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE FLAGSTAFF AZ 255 PM MST SAT SEP 12 2009 .SYNOPSIS...A MOIST AND UNSTABLE AIR MASS WILL CONTINUE TO PRODUCE SCATTERED AFTERNOON AND EVENING THUNDERSTORMS FOR THE NEXT SEVERAL DAYS. THERE WILL BE A MODEST INCREASE IN SHOWER AND THUNDERSTORM ACTIVITY SUNDAY AND MONDAY...AS A PACIFIC LOW PRESSURE SYSTEM MOVES INTO THE GREAT BASIN. NEAR NORMAL DAYTIME TEMPERATURES ARE EXPECTED TO CONTINUE. && .DISCUSSION...A WEAK DECAYING FRONTAL BAND HAS DROPPED SOUTH THROUGH THE NORTHEAST PLATEAUS AND INTO PORTIONS OF THE LITTLE COLORADO RIVER VALLEY...BRINGING A LITTLE DRIER AIR AND LESS THUNDERSTORM ACTIVITY TO THAT REGION. MEAN WHILE A RELATIVELY UNSTABLE AIRMASS ALONG WITH DEEPER MOISTURE RESIDES ALONG THE WHITE MOUNTAINS...ALONG AND WEST OF THE MOGOLLON RIM INTO YAVAPAI COUNTY...AND OVER THE COCONINO AND KAIBAB PLATEAUS. CURRENT RUC40 INDICATING THAT THE TEMPERATURES ALOFT AT 500 MB AND ABOVE ARE FORECAST TO CONTINUE TO COOL...OVER WEST CENTRAL AND NORTHWEST ARIZONA THIS AFTERNOON... WHICH WILL FURTHER AID THUNDERSTORM ACTIVITY AND DEVELOPMENT. STORMS ARE FORECAST TO DROP SOUTH SOUTHEAST OVER THESE AREAS LATE THIS AFTERNOON AND EARLY EVENING. CHCS OF PRECIP HAVE BEEN INCREASED OVER PORTIONS OF YAVAPAI AND COCONINO COUNTIES FOR LATE THIS AFTERNOON AND EVENING TO ACCOUNT FOR CURRENT STORM TRENDS. MOISTURE WILL LINGER OVER THE REGION...AND INTERACT WITH A COUPLE OF WEATHER SYSTEMS MOVING THROUGH THE AREA DURING THE FORECAST PERIOD. SCATTERED TO POSSIBLY NUMEROUS THUNDERSTORMS WILL DEVELOP BY SUNDAY AFTERNOON AND CONTINUE INTO MONDAY EVENING. A LOW PRESSURE SYSTEM IS FORECAST TO MOVE INTO NEVADA LATE SUNDAY AND MOVE ACROSS UTAH LATE MONDAY. THIS WEATHER SYSTEM WILL INCREASE SYNOPTIC LIFT OVER NORTHERN ARIZONA SUNDAY NIGHT INTO MONDAY ALONG WITH BRINGING COLDER AIR ALOFT WHICH WILL HELP DESTABILIZE THE ATMOSPHERE. THIS STORM SYSTEM AS IT APPROACHES WILL DRAW DEEPER MOISTURE NORTH AND WEST INTO NORTHERN ARIZONA. THE FLOW ALOFT IS FORECAST TO INCREASE AS THIS LOW PRESSURE SYSTEM APPROACHES NORTHERN ARIZONA...SO THAT THERE WILL BE AN INCREASED THREAT OF ORGANIZED ISOLATED SEVERE THUNDERSTORMS ESPECIALLY MONDAY AFTERNOON AND EVENING. THE MAIN WEATHER IMPACTS WILL BE THE INCREASED THREAT OF ISOLATED SEVERE HAIL AND LOCALIZED AREAS OF HEAVY RAINFALL AND POSSIBLE FLASH FLOODING FROM THE STRONGER STORMS. BY LATE MONDAY NIGHT EARLY TUESDAY MORNING THE GFS FORECASTS THAT DRIER AIR WILL SWEEP ACROSS NORTHERN ARIZONA DIMINISHING THE THREAT OF SHOWERS AND THUNDERSTORMS...TO WIDELY SCATTERED ACTIVITY MAINLY OVER NORTHEAST AND EAST CENTRAL ARIZONA ON TUESDAY. GIVEN THE BLOCKING PATTERN THAT IS CURRENTLY AFFECTING THE WESTERN U.S...MODEL RUN-TO-RUN CONSISTENCY HAS NOT BEEN AS GOOD IN THE 4 TO 7 DAY TIME PERIOD. SO LESS CONFIDENCE IS PLACED ON THE WEDNESDAY THROUGH SATURDAY FORECASTS...GENERAL MODEL TRENDS AND CLIMATOLOGY HAVE BEEN WOVEN TOGETHER AND ARE DEPICTED IN OUR CURRENT GRAPHICAL FORECASTS PACKAGE. THE LOW IS FORECAST TO DROP SOUTH OVER THE FOUR CORNERS AREA BY THURSDAY MORNING WITH THE POSSIBILITY OF WIDESPREAD RAIN SHOWERS OVER THE NORTHEAST AND SCATTERED SHOWERS SOUTHWARD TO THE EASTERN MOGOLLON RIM AND WHITE MOUNTAINS. BY LATE FRIDAY INTO SATURDAY THE UNSETTLED WEATHER PATTERN WILL MOVE INTO EASTERN NEW MEXICO TEXAS PANHANDLE WITH HIGH PRESSURE AND DRIER CONDITIONS BUILDING INTO NORTHERN ARIZONA. && .AVIATION...FOR THE 00Z PACKAGE...TIL 02Z SUN...SCATTERED THUNDERSTORMS WILL CONTINUE S OF A KIGM-KRQE LINE...WITH ISOLATED STORMS N OF THIS LINE. LOOK FOR LOCAL MVFR CONDITIONS AND GUSTY WINDS WITH THE STORMS. AFT 02Z SUN...CONVECTION TO DIMINISH WITH VFR CONDITIONS OVERNIGHT. AFT 17Z SUNDAY...SW SFC WINDS AT 10-20KT WILL DEVELOP. SCATTERED THUNDERSTORMS ARE EXPECTED ACROSS ALL OVER NORTHERN ARIZONA DURING THE AFTERNOON. AVIATION DISCUSSION NOT UPDATED FOR AMENDMENTS. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && PUBLIC.......................TC AVIATION/FIRE WEATHER........DL VISIT WEATHER.GOV/FLAGSTAFF FOR NORTHERN ARIZONA WEATHER INFORMATION.
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE FLAGSTAFF AZ 1010 AM MST SAT SEP 12 2009 AZZ004>018-037>040-130700- WESTERN MOGOLLON RIM-GRAND CANYON COUNTRY-YAVAPAI COUNTY MOUNTAINS- YAVAPAI COUNTY VALLEYS AND BASINS-OAK CREEK AND SYCAMORE CANYONS- MARBLE AND GLEN CANYONS-KAIBAB PLATEAU-COCONINO PLATEAU- NORTHEAST PLATEAU AND MESAS HWY 264 NORTHWARD- NORTHEAST PLATEAU AND MESAS SOUTH OF HWY 264- CHINLE VALLEY-CHUSKA MOUNTAINS AND DEFIANCE PLATEAU- BLACK MESA AREA-LITTLE COLORADO RIVER VALLEY IN COCONINO COUNTY- LITTLE COLORADO RIVER VALLEY IN NAVAJO COUNTY- LITTLE COLORADO RIVER VALLEY IN APACHE COUNTY- EASTERN MOGOLLON RIM-WHITE MOUNTAINS-NORTHERN GILA COUNTY- 1010 AM MST SAT SEP 12 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR APACHE...COCONINO...NORTHERN GILA...NAVAJO...AND YAVAPAI COUNTIES IN NORTHERN ARIZONA. .DAY ONE...TODAY THE MAIN THUNDERSTORM THREAT AREA WILL BE OVER THE EASTERN MOGOLLON RIM...WHITE MOUNTAINS...WITH STORMS SHIFTING SOUTH INTO PORTIONS OF ...SOUTHEAST YAVAPAI AND NORTHERN GILA COUNTY BY EARLY EVENING. THE WEATHER HAZARD TODAY WILL BE HEAVY RAIN AND LOCALIZED FLOODING AND HAIL FROM THE STRONGER THUNDERSTORMS...FROM THE EASTERN MOGOLLON RIM AND WHITE MOUNTAINS SOUTH. THUNDERSTORMS WILL GET A LITTLE LATER START TODAY OVER THE EASTERN RIM AND WHITE MOUNTAINS...POSSIBLY BY NOON. FOR THE REMAINDER OF THE AREA THUNDERSTORMS WILL DEVELOP BY EARLY TO LATE AFTERNOON...WITH A SLIGHT INCREASE DURING THE EVENING HOURS. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY MOISTURE WILL LINGER OVER THE REGION...AND INTERACT WITH A COUPLE OF WEATHER SYSTEMS MOVING THROUGH THE AREA DURING THE FORECAST PERIOD. SCATTERED TO POSSIBLY NUMEROUS THUNDERSTORMS WILL DEVELOP BY SUNDAY AFTERNOON AND CONTINUE INTO MONDAY EVENING. A LOW PRESSURE SYSTEM IS FORECAST TO MOVE INTO NEVADA LATE SUNDAY AND MOVE ACROSS UTAH LATE MONDAY. THIS WEATHER SYSTEM WILL INCREASE OUR CHANCES FOR SHOWERS AND THUNDERSTORMS...ESPECIALLY SUNDAY NIGHT INTO MONDAY. THE MAIN WEATHER IMPACTS WILL BE ISOLATED HAIL AND LOCALIZED AREAS OF HEAVY RAINFALL AND POSSIBLE FLASH FLOODING FROM THE STRONGER STORMS. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.
The Flagstaff radar (KFSX), 82 km away, was scanning. The volume nearest the first event began at 23:43 UTC.
1 heavy rain, 1 flash flood. Local standard time, as filed.
Heavy rain and flowing washes were reported by a spotter 3 miles southwest of Cottonwood.
Two to three feet of flowing water in a low water crossing trapped one car. A swift water rescue was performed on the driver.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Arizona in 2009Every state in 2009This day in weather historyWarnings in Arizona, September 2009
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: 197157, 197156.