A mid level trough returned with abundant moisture from the southeast to generate thunderstorms across southeast Arizona. Some storms produced heavy rain and flash flooding while others produced damaging wind gusts.
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 TWC wrote it up.
A mid level trough returned with abundant moisture from the southeast to generate thunderstorms across southeast Arizona. Some storms produced heavy rain and flash flooding while others produced damaging wind gusts.
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 Aug 14, 9:17 PM MST, 4 hours 38 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TUCSON AZ 917 PM MST TUE AUG 14 2012 .SYNOPSIS...EXPECT AN INCREASE IN THUNDERSTORM CHANCES THE NEXT SEVERAL DAYS AS HUMIDITY INCREASES ACROSS SOUTHEAST ARIZONA. SOME AREAS MAY STILL SEE TRIPLE DIGIT TEMPERATURES WEDNESDAY BUT A GRADUAL TREND BACK TO NEAR NORMAL TEMPERATURES IS EXPECTED THIS WEEK. && .DISCUSSION...IR SATELLITE IMAGERY SHOWS A MASSIVE MCS OVER CENTRAL AND SOUTHERN SONORA MEXICO BUT EXTENDING NORTHWARD INTO SOUTHERN ARIZONA AS WELL. CLOUD TOP TEMPERATURES AS COLD AS MINUS 77 DEGS CELSIUS BUT THEY WERE AS COLD AS MINUS 84 DEGS CELSIUS EARLIER THIS EVENING. RADAR MOSAIC SHOWS SHOWER AND THUNDERSTORM ACTIVITY ON THE DECLINE...AT LEAST FOR MOST OF MY FORECAST AREA. NEW DEVELOPMENT HAS BEGUN OVER PORTIONS OF PINAL COUNTY AND MOVING SOUTH. EARLIER TODAY THE 12Z RUN OF WRF-NAM MODEL WAS SHOWING A REDEVELOPMENT OF ACTIVITY OVERNIGHT TONIGHT GENERALLY BETWEEN AROUND 11Z-14Z OVER THE TOHONO O'ODHAM NATION. NOT SURE IF THIS WILL OCCUR...BUT CAN'T RULE IT OUT...ESPECIALLY WITH THE BIG COMPLEX TO OUR SOUTH POTENTIALLY PUSHING OUTFLOWS AND HIGHER MOISTURE INTO SOUTHERN ARIZONA. THE INHERITED POP GRIDS KEEP SLIGHT CHANCE POPS IN THE FORECAST AREA-WIDE OVERNIGHT. THIS SEEMS COMPLETELY REASONABLE TO ME...SO NO CHANGES ARE PLANNED AT THIS TIME. IN FACT IT MAY NOT BE HIGH ENOUGH OUT WEST IF THE WRF-NAM SOLUTION COMES TO PASS. OVERNIGHT TEMPERATURES NEED SOME ADJUSTING HERE AND THERE...SO WILL BE MAKING SOME TWEAKS TO THE TEMPERATURE FORECAST IN THE SHORT TERM AND WILL SEND OUT UPDATES SHORTLY. && .AVIATION...ISOLD TSRA/SHRA THROUGH 15/18Z...THEN SCT TSRA COVERAGE AGAIN WEDNESDAY AFTERNOON. EXTENSIVE CLOUD DECKS OVERNIGHT WITH CEILINGS 8-12K FT. OTHERWISE...SURFACE WIND GENERALLY LESS THAN 12 KTS THRU 16/00Z. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...A COOLING TREND WILL START WEDNESDAY AND CONTINUE INTO THE UPCOMING WEEKEND. SIGNIFICANTLY COOLER DAYTIME READINGS ARE EXPECTED BY THURSDAY OR FRIDAY AS INCREASING CLOUDS AND MOISTURE MOVE BACK INTO SOUTHEAST ARIZONA. WITH THE DEEPER MOISTURE IN PLACE...PRECIPITATION CHANCES WILL INCREASE DURING THE MIDDLE TO LATTER PORTIONS OF THE WORK WEEK. ALSO EXPECT STRONG...GUSTY AND ERRATIC WINDS NEAR ANY THUNDERSTORMS THAT DO DEVELOP. && .CLIMATE...THE TUCSON INTERNATIONAL AIRPORT REACHED 106 DEGREES TODAY...WHICH TIES THE RECORD OF 106 FOR AUGUST 14TH. THIS IS ALSO THE 9TH STRAIGHT DAY WITH A HIGH OF 105 DEGREES OR GREATER...WHICH IS ONE DAY SHY OF THE AUGUST RECORD OF 10 DAYS SET IN 1995. && .PREVIOUS DISCUSSION...EXPECT TO GET AN OUTFLOW FROM THIS MCS TO PUSH MOISTURE NORTHWARD LATER TONIGHT INTO WED MORNING. THIS WILL ALSO SERVE TO GRAB MORE GULF OF CALIFORNIA MOISTURE AND BRING IT INTO AZ. THIS SURGE MAY BE REINFORCED BY LARGER SCALE FEATURE EVIDENT ON SATELLITE FARTHER SOUTH IN CHIHUAHUA AND SONORA HEADING OUR WAY. WHILE THAT COULD MEAN AN UPTICK IN STORM COVERAGE WEDNESDAY...IT COULD ALSO LEAD TO SO MUCH CLOUD COVER THAT OUR TEMPERATURES STRUGGLE TO WARM WHICH WOULD LIMIT CONVECTIVE DEVELOPMENT. AT THIS TIME WILL GO WITH MODERATE POPS BETWEEN THE DRIER MET AND WETTER MAV POP GUIDANCE VALUES...BUT HAVE TRIMMED AFTERNOON TEMPERATURES JUST A SHADE OVER GOING FORECAST. MODELS INDICATE THAT THE UPPER HIGH WILL GRADUALLY MOVE NORTHWARD THIS WEEK PLACING SE AZ IN A MOIST SE FLOW. THUS HAVE RAISED POPS SLIGHTLY WHICH ALREADY INDICATED ACTIVE THUNDERSTORM CHANCES THURSDAY INTO AT LEAST THE FIRST PART OF THE WEEKEND. AS MOISTURE INCREASES...THE RISK FOR HEAVY RAIN AND FLASH FLOODING WILL ALSO INCREASE. THE ADDITIONAL THUNDERSTORM ACTIVITY WILL ALSO CORRESPOND WITH MORE SEASONABLE HIGH TEMPERATURES...SO THE STRING OF 100 DEGREE HIGH TEMPERATURES FOR TUCSON WILL COME TO AN END WEDNESDAY OR THURSDAY. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE && CURRENT DISCUSSION...GM PREVIOUS DISCUSSION...KD/GL
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE TUCSON AZ 810 AM MST TUE AUG 14 2012 AZZ501>515-150700- WESTERN PIMA COUNTY-TOHONO O'ODHAM NATION- UPPER SANTA CRUZ RIVER VALLEY/ALTAR VALLEY-TUCSON METRO AREA- SOUTH CENTRAL PINAL COUNTY-SOUTHEAST PINAL COUNTY- UPPER SAN PEDRO RIVER VALLEY- EASTERN COCHISE COUNTY BELOW 5000 FEET-UPPER GILA RIVER VALLEY- WHITE MOUNTAINS OF GRAHAM AND GREENLEE COUNTIES- GALIURO AND PINALENO MOUNTAINS-CHIRICAHUA MOUNTAINS- DRAGOON AND MULE AND HUACHUCA AND SANTA RITA MOUNTAINS- CATALINA AND RINCON MOUNTAINS-BABOQUIVARI MOUNTAINS- 810 AM MST TUE AUG 14 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST ARIZONA. .DAY ONE...TODAY AND TONIGHT VERY HOT HIGH TEMPERATURES BETWEEN 105 AND 110 DEGREES ARE FORECAST ACROSS THE VALLEYS BELOW 3000 FEET TODAY. IN ADDITION...ISOLATED TO SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP AGAIN IN MOST AREAS THIS AFTERNOON AND CONTINUE INTO THE EVENING. THE MOST CONCENTRATED AREA OF STORMS IS FORECAST ALONG THE INTERNATIONAL BORDER. THE MAIN THREATS FROM THUNDERSTORMS TODAY AND TONIGHT WILL BE DAMAGING WIND GUSTS OF 55 TO 65 MPH...ALONG WITH DANGEROUS CLOUD TO GROUND LIGHTNING STRIKES. LOCATIONS THAT GET HIT BY A SLOW MOVING THUNDERSTORM OR BY MORE THAN ONE THUNDERSTORM COULD RECEIVE HEAVY RAIN AMOUNTS. .DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY AFTER ANOTHER HOT DAY WEDNESDAY WHEN HIGH TEMPERATURES BETWEEN 103 AND 108 ARE FORECAST BELOW 3000 FEET...TEMPERATURES SHOULD TREND DOWN CLOSER TO MID AUGUST AVERAGES THE REST OF THE WEEK. HOWEVER...THUNDERSTORM COVERAGE WILL INCREASE FOR THE LATTER HALF OF THE WORK WEEK AND INTO THE WEEKEND. THE MAIN THREAT FROM THUNDERSTORMS WILL SHIFT FROM GUSTY WINDS TO HEAVY RAIN AND FLASH FLOODING. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES. KD WEATHER.GOV/TUCSON
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TUCSON AZ
932 PM MST TUE AUG 14 2012
AZZ502-504>507-514-150530-
SANTA CATALINA AND RINCON MOUNTAINS INCLUDING MOUNT
LEMMON/SUMMERHAVEN AZ-SOUTH CENTRAL PINAL COUNTY INCLUDING
ELOY/PICACHO PEAK STATE PARK AZ-SOUTHEAST PINAL COUNTY INCLUDING
KEARNY/MAMMOTH/ORACLE AZ-TOHONO O'ODHAM NATION INCLUDING SELLS
AZ-TUCSON METRO AREA INCLUDING TUCSON/GREEN VALLEY/MARANA/VAIL
AZ-UPPER SAN PEDRO RIVER VALLEY INCLUDING SIERRA VISTA/BENSON AZ-
932 PM MST TUE AUG 14 2012
...SIGNIFICANT WEATHER ADVISORY FOR EASTERN PINAL AND NORTHEASTERN
PIMA COUNTIES UNTIL 1030 PM MST...
AT 924 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
THAT SHOWERS HAD REDEVELOPED OVER NORTHEAST PORTIONS OF PIMA COUNTY
AND SOUTHEAST PORTIONS OF PINAL COUNTY WITH A STRONG THUNDERSTORM 5
MILES SOUTHWEST OF ORO VALLEY...MOVING SOUTH AT 15 MPH.
WIND GUSTS UP TO 40 MPH ARE EXPECTED WITH SOME OF THESE STORMS...
ALONG WITH HEAVY RAIN.
AREAS AFFECTED BY THIS STORM INCLUDE...NORTHWEST PORTIONS OF
TUCSON...PICTURE ROCKS...SAGUARO NATIONAL PARK EAST...SAGUARO
NATIONAL PARK WEST.
LAT...LON 3267 11066 3212 11065 3218 11129 3283 11155
3322 11100
TIME...MOT...LOC 0430Z 014DEG 13KT 3234 11102The Phoenix radar (KIWA), 106 km away, was scanning. The volume nearest the first event began at 08:55 UTC.
1 thunderstorm wind, 1 flash flood. Local standard time, as filed.
Thunderstorm winds damaged roofs to two homes in Ventana.
Between two and four inches of rain fell across parts of Santa Cruz County. Several motorists were rescued from their vehicles in Nogales and Rio Rico as water ran across roads to depths over three feet in some spots. Another swift water rescue occurred at the Potero Wash along South River Road. In addition, Nogales Wash came out of its banks and flooded nearby businesses in Nogales.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Arizona in 2012Every state in 2012This day in weather historyWarnings in Arizona, August 2012
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: 408980, 408988.