An increase in low level moisture combined with a weak upper level disturbance and generated isolated thunderstorms across the Tucson area. These storms produced heavy rainfall and flash flooding.
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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 TWC wrote it up.
An increase in low level moisture combined with a weak upper level disturbance and generated isolated thunderstorms across the Tucson area. These storms produced heavy rainfall and flash flooding.
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 Tucson, AZ wrote its last area forecast discussion before the first event at May 16, 2:30 PM MST, 1 hour 50 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TUCSON AZ 230 PM MST WED MAY 16 2007 .SYNOPSIS...THE MOISTURE INCREASE OF THE PAST DAY WILL LEAD TO AN INCREASE IN SHOWER AND THUNDERSTORM ACTIVITY STARTING TONIGHT AND CONTINUE INTO FRIDAY. SEVERAL UPPER LEVEL DISTURBANCES WILL MOVE THE REGION AND HELP IN THE DEVELOPMENT OF STORMS. THE FIRST DISTURBANCE WILL MOVE THROUGH TONIGHT. WESTERLY FLOW ALOFT WILL BRING DRIER CONDITIONS BY LATE IN THE WEEKEND. && .DISCUSSION...AS I MENTIONED IN THE MORNING DISCUSSION...IT SURE LOOKS LIKE IT IS SHAPING UP TO BE A VERY INTERESTING MAY DAY. THE LOW LEVEL MOISTURE INCREASE FROM LAST NIGHT CONVECTION IN SOUTHWEST NEW MEXICO HAS STUCK AROUND WITH AFTERNOON SURFACE DEWPOINTS STILL HANGING IN THE UPPER 30S TO UPPER 40S. BACK DOOR FRONT IS STILL OVER FAR EASTERN ARIZONA THIS AFTERNOON WHILE ALOFT AN WEAK DISTURBANCE IS HEADED OUR WAY IN SOUTHWEST FLOW ALOFT. AS OF 2 PM...WATER VAPOR PLACED THIS FEATURE OVER FAR NORTHWEST SONORA MEXICO...MOVING NORTHEAST AROUND 25 MPH. THIS DISTURBANCE HAS BECOME NEGATIVELY TILTED AND DIVERGENCE ALOFT HAS INCREASED OVER THE AREA THIS AFTERNOON...WITH CONVECTION ALREADY OCCURRING ON THE RIM AND SOUTH OF TUCSON. GOES SOUNDER PRECIPITABLE WATER IMAGERY THIS AFTERNOON SHOWED THAT MOISTURE HAS REALLY INCREASED OVER THE AREA WITH SOME VALUES OVER ONE INCH IN SPOTS ACROSS SOUTHERN HALF OF ARIZONA...WHICH WOULD BE ALMOST 200% OF NORMAL. AS I ALSO MENTIONED THIS MORNING...FROM THE THE 12Z MODEL RUNS...IT APPEARED THAT THE NAM/RUC MODELS WERE RESOLVING AFTERNOON/EVENING ACTIVITY BETTER THAN GFS/NGM. THAT HAS CONTINUED ON THE 18Z RUNS AS THEY BOTH DEVELOPED A NW-SE ORIENTED LINE OF STORMS FROM WESTERN PINAL COUNTY SOUTHEAST INTO COCHISE COUNTY THIS AFTERNOON. RADAR AS OF 215 PM...THUNDERSTORMS WERE DEVELOPING SOUTH OF TUCSON...MOVING NORTH AROUND 10-12 MPH. MAIN THREAT FROM STORMS LATER THIS AFTERNOON INTO THIS EVENING...DUE TO INVERTED V SOUNDING PROFILES...WILL BE STRONG DOWNBURST WINDS...WHICH WILL DEVELOP AREAS OF BLOWING DUST...SMALL HAIL...AND BRIEF HEAVY RAIN. AS THE UPPER LEVEL DISTURBANCE MOVES NORTHEAST THIS EVENING ACTIVITY WILL BE ENDING FROM WEST TO EAST WITH SOME LINGERING SHOWERS ALONG THE AZ/NM BORDER. THURSDAY LOOKS LIKE A REPEAT OF TODAY AS ANOTHER DISTURBANCE ALOFT MOVES ACROSS THE AREA. 18Z NAM PAINTS THE BEST AREA NORTH AND EAST OF TUCSON. LINGERING STORMS EAST OF TUCSON FRIDAY INTO SATURDAY BEFORE DRIER WESTERLY FLOW PUSHES MOISTURE OUT OF AREA. TEMPERATURES WILL REMAIN ABOVE NORMAL...WITH AREAS GETTING HIT BY HEAVY RAIN...SEEING COOLER THAN WHAT IM CURRENTLY FORECASTING. JUST CANT PINPOINT WHERE THOSE AREAS WILL BE AT THIS TIME. NEXT WEEK LOOKS DRY AT THIS TIME. HOWEVER...LATEST GFS WANTS TO BREAK OFF SOUTHERN END OF TROF MOVING THROUGH THE NORTHERN ROCKIES AND DEVELOP CLOSED LOW OVER THE STATE. WILL NOT BUT INTO THIS SOLUTION AT THIS MOMENT AS THE ENSEMBLES ARE NOT ALL IN AGREEMENT WITH THE OPERATIONAL RUN. ANYWAY...DEFINITELY UN-MAY LIKE WEATHER IN STORE FOR THE AREA OVER THE NEXT 3 TO 4 DAYS. ENJOY. WE SURE COULD USE THE RAIN. && .FIRE WEATHER...A SIGNIFICANT INCREASE IN MOISTURE ACROSS SOUTHEAST ARIZONA TODAY HAVE PROMPTED THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS. THESE SHOWERS AND THUNDERSTORMS ARE EXPECTED TO BECOME MORE WIDESPREAD THROUGH THE EVENING HOURS. SIGNIFICANT AMOUNTS OF LIGHTNING ARE EXPECTED WITH THUNDERSTORMS THIS AFTERNOON AND EVENING...WITH COUNTS OF 10 TO 25 PER 15 MINUTES EXPECTED. THIS MOISTURE WILL LINGER ACROSS MOSTLY THE EASTERN ZONES THROUGH AT LEAST FRIDAY...WITH SHOWERS AND THUNDERSTORMS EXPECTED EACH AFTERNOON AND EVENING. DRIER CONDITIONS WILL MOVE BACK INTO ARIZONA LATE IN THE WEEKEND. && .AVIATION...AREAL COVERAGE OF THUNDERSTORMS WILL CONTINUE TO INCREASE THIS EVENING ACROSS SOUTHEAST ARIZONA WITH A 50-50 CHANCE THAT STRONG WINDS OVER 40 KNOTS WILL HIT TUCSON INTERNATIONAL AIRPORT BETWEEN 22Z AND 02Z. CLOUD BASES GENERALLY 10-12K FT AGL THOUGH LOWERING TO ABOUT 5K FT IN THE STRONGEST STORMS. MAIN IMPACT WILL BE STRONG OUTFLOW WINDS ESPECIALLY FROM THE TUCSON AREA NWWD AFTER ABOUT 22Z TIL AROUND 06Z...PRODUCING AREAS BLDU WITH VSBYS NEAR 1SM OR LESS. WIND GUSTS MAY APPROACH 50KTS WITH THE STRONGEST STORMS. AVIATION DISCUSSION NOT UPDATED FOR TAF OR TWEB AMENDMENTS. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. && JRG WEATHER.GOV/TUCSON
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE TUCSON AZ 335 PM MST WED MAY 16 2007 AZZ029-033>035-171045- SOUTHEAST PINAL COUNTY-TUCSON METRO/MARANA/GREEN VALLEY- SANTA CRUZ COUNTY-COCHISE COUNTY- 335 PM MST WED MAY 16 2007 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PINAL...PIMA...SANTA CRUZ AND COCHISE COUNTIES. .DAY ONE...THIS AFTERNOON AND TONIGHT AN UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE AREA THIS AFTERNOON AND TONIGHT WHILE ABUNDANT MOISTURE FOR MAY RESIDES ACROSS THE AREA. THIS WILL LEAD TO THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS. A FEW OF THE STRONGER THUNDERSTORMS WILL HAVE THE POTENTIAL TO PRODUCE SMALL HAIL AND BRIEF WIND GUSTS BETWEEN 45 TO 55 MPH. THESE GUSTY THUNDERSTORM OUTFLOWS WILL ALSO HAVE THE POTENTIAL TO PRODUCE AREAS OF BLOWING DUST. AN AREA SUSCEPTIBLE TO HAZARDOUS BLOWING DUST CONDITIONS IS ALONG THE INTERSTATE-10 CORRIDOR FROM TUCSON TO CASA GRANDE. VISIBILITIES MAY BE REDUCED TO ONE MILE OR LESS IN BLOWING DUST LATER THIS AFTERNOON AND EARLY EVENING. A DECREASE IN SHOWERS AND THUNDERSTORM COVERAGE AND INTENSITY IS EXPECTED AFTER SUNSET. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. LINGERING MOISTURE WILL LEAD TO ANOTHER CHANCE OF AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS ON THURSDAY. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. AZZ030-171045- UPPER GILA RIVER VALLEY- 335 PM MST WED MAY 16 2007 THIS HAZARDOUS WEATHER OUTLOOK IS FOR GRAHAM AND SOUTHERN GREENLEE COUNTIES. .DAY ONE...THIS AFTERNOON AND TONIGHT AN UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE AREA TONIGHT WHILE ABUNDANT MOISTURE FOR MAY RESIDES ACROSS THE AREA. THIS WILL LEAD TO THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS. A FEW OF THE STRONGER THUNDERSTORMS WILL HAVE THE POTENTIAL TO PRODUCE SMALL HAIL...BRIEF WIND GUSTS BETWEEN 45 TO 55 MPH AND BRIEF HEAVY RAIN. SOME RAINFALL AMOUNTS COULD BE UP TO ONE INCH IN LOCALIZED AREA...ESPECIALLY SOUTHWEST OF SAFFORD. A DECREASE IN SHOWERS AND THUNDERSTORM COVERAGE WILL OCCUR OVERNIGHT. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. LINGERING MOISTURE THROUGH FRIDAY WILL LEAD TO A CHANCE OF AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS EACH DAY. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. AZZ019-171045- NORTHERN GREENLEE COUNTY- 335 PM MST WED MAY 16 2007 THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHERN GREENLEE COUNTY. .DAY ONE...THIS AFTERNOON AND TONIGHT AN UPPER LEVEL DISTURBANCE WILL MOVE ACROSS THE AREA TONIGHT WHILE ABUNDANT MOISTURE FOR MAY RESIDES ACROSS THE AREA. THIS WILL LEAD TO THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS. A FEW OF THE STRONGER THUNDERSTORMS WILL HAVE THE POTENTIAL TO PRODUCE SMALL HAIL...BRIEF WIND GUSTS BETWEEN 45 TO 55 MPH AND BRIEF HEAVY RAIN. SOME RAINFALL AMOUNTS COULD BE UP TO ONE INCH IN LOCALIZED AREAS. A DECREASE IN SHOWERS AND THUNDERSTORM COVERAGE WILL OCCUR OVERNIGHT. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. LINGERING MOISTURE THROUGH SATURDAY WILL LEAD TO CHANCE OF AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS EACH DAY. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.
The Tucson radar (KEMX), 68 km away, was scanning. The volume nearest the first event began at 23:19 UTC.
1 flash flood. Local standard time, as filed.
Flash flooding from thunderstorms caused a vehicle to be swept into fast moving water at North Bobcat Ridge Trail and West Ina Road on the northwest side of Tucson. The vehicle was washed downstream for about 200 feet before coming to a stop on a bank.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Arizona in 2007Every state in 2007This day in weather historyWarnings in Arizona, May 2007
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: 26358.