Daytime heating in combination with a moist flow caused thunderstorms to develop across Southeast Arizona.
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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.
Daytime heating in combination with a moist flow caused thunderstorms to develop across Southeast Arizona.
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 Jul 21, 2:27 PM MST, 33 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TUCSON AZ 227 PM MST SAT JUL 21 2007 .SYNOPSIS...ABUNDANT MOISTURE IN COMBINATION WITH DAYTIME HEATING AND A FAVORABLE FLOW WILL PROVIDE THUNDERSTORMS MAINLY DURING THE AFTERNOON AND EVENING HOURS INTO NEXT WEEK. DAYTIME HIGH TEMPERATURES WILL ALSO BE BELOW NORMAL THIS WEEKEND AND INTO EARLY NEXT WEEK. && .DISCUSSION...WATER VAPOR IMAGERY SHOWS AN UPPER LEVEL INVERTED TROUGH THAT EXTENDS FROM THE PACIFIC WATERS WEST OF THE SOUTHERN BAJA PENINSULA INTO W CENTRAL NEW MEXICO. A WEAK LOW CAN BE SEEN SPINNING OVER WEST CENTRAL NEW MEXICO...AND THIS FEATURE IS PROGGED TO LIFT SLOWLY TO THE WEST BY THE NAM...AND MORE TO THE NW BY THE GFS. THE NAM PUSHES IT INTO MY EASTERN CWA THIS AFTERNOON...BUT THE GFS HAS IT MORE OVER THE WHITE MOUNTAINS BY THEN. CURRENTLY RADAR MOSAIC IS DETECTING ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS OVER THE HIGHER TERRAIN OF WEST CENTRAL NEW MEXICO...WITH SHOWERS CURRENTLY EXTENDING FROM AROUND THE RESERVE AREA SOUTHWARD TO NEAR LORDSBURG AND DEMING. ELSEWHERE STORMS HAVE ALSO BEEN DEVELOPING ALONG THE MOGOLLON RIM AND OVER THE HIGHER ELEVATIONS OF NORTHERN ARIZONA. THESE SHOWERS & THUNDERSTORMS ARE MOVING SLOWLY TO THE SOUTHWEST OR WEST. ISOLATED ACTIVITY HAS BEGUN TO DEVELOP OVER THE MOUNTAINS WITHIN MY CWA. THIS MORNINGS KTWC SOUNDING SHOWS SLIGHT WARMING NEAR THE SURFACE UP TO AROUND 860MB...WHILE COOLING IN THE BOUNDARY LAYER HAS OCCURRED FROM AROUND 860-650MB. ABOVE THAT LEVEL THE TEMPS ARE SIMILAR TO 24 HOURS AGO. THE COOLING HAS RESULTED IN LAPSE RATES THAT ARE NOT AS STEEP...THUS WE SHOULD SEE SOME INHIBITION TO THE DEVELOPMENT TODAY. THE SOUNDING DOES SHOW SOME DECENT WINDS IN THE UPPER LEVELS WITH AROUND 15 TO 25 KNOTS IN THE 700-500MB LAYER. THE UNMODIFIED SOUNDING SHOWS A PW OF AROUND AN INCH AND A HALF...WITH A LIFTED INDEX OF MINUS 4 AND A CAPE OF AROUND 950 J/KG. MODIFYING THE SOUNDING USING T=95TD=59 YIELDS SIMILAR RESULTS...BUT WITH A CAPE OF AROUND 1250 J/KG IF LIFTING FROM THE SURFACE...BUT ONLY AROUND 400 J/KG IF LIFTING USING THE MEAN TEMP METHOD...WHICH MAY BE MORE REPRESENTATIVE. SATELLITE IMAGERY INDICATES THAT THE EXTENSIVE CLOUDINESS THAT WAS OVER MUCH OF NORTHERN MEXICO AND SOUTHERN ARIZONA OVERNIGHT AND THIS MORNING HAS BEEN SLOWLY ERODING. THEREFORE...WITH THE ADDITION OF INSOLATION THROUGH THE AFTERNOON HOURS...EXPECTING STORMS TO BEGIN TO DEVELOP WITHIN MY CWA AS THE AFTERNOON PROGRESSES. SPC IS STILL INDICATING THE POTENTIAL FOR A FEW ISOLATED POTENTIALLY SEVERE STORMS OVER THE AREA LATE THIS AFTERNOON AND EVENING. THINK THE PEAK OF ACTIVITY FOR MY FORECAST AREA WILL OCCUR DURING THE EVENING AND POSSIBLY CONTINUING INTO THE OVERNIGHT HOURS. WITH THE RATHER SLOW MOVEMENT AND WARM TOPS OVER THE RIM AND WEST CENTRAL NEW MEXICO... SOME LOCALIZED FLOODING COULD BE AN ISSUE LATER ON TODAY. NAM INDICATES THAT THE UPPER LOW OVER WEST CENTRAL NEW MEXICO WILL MEANDER ACROSS THAT AREA THROUGH LATE SUNDAY BEFORE FINALLY LIFTING OFF TO THE NW WITH THE NAM SHOWING A CIRCULATION CENTER FARTHER SOUTH OVER MY CWA THAT MOVES FROM THE CENTER OF MY FORECAST AREA BEGINNING AT AROUND 00Z MONDAY AND PUSHES SW TOWARD ORGAN PIPE BY AROUND 12Z MONDAY. NAM SHOWS ANOTHER IMPULSE MOVING UP FROM SONORA ON MONDAY INTO THE WESTERN PORTIONS OF MY FORECAST AREA WHICH SHOULD HELP ENHANCE ACTIVITY OVER THE FAR WESTERN DESERTS. DEEP EASTERLY FLOW WILL CONTINUE TO BRING MOISTURE IN THE AREA ON TUESDAY WITH A CONTINUATION OF FAIRLY HIGH (SCATTERED CATEGORY) RAIN CHANCES. WITH A WET PATTERN STILL IN PLACE I KEPT THE POPS GRIDS AS I INHERITED THEM THROUGH EARLY NEXT WEEKEND. HIGH FOR THE TUCSON AREA WILL REMAIN IN THE MID TO UPPER 90S THROUGH THE PERIOD WITH LOWS IN THE MID TO UPPER 70S. && .FIRE WEATHER...THE DAILY CYCLE OF MAINLY AFTERNOON AND EVENING THUNDERSTORMS WILL CONTINUE THIS WEEKEND AND INTO NEXT WEEK. ANY THUNDERSTORMS THAT OCCUR WILL BE CAPABLE OF PRODUCING STRONG...GUSTY AND ERRATIC WINDS. RELATIVE HUMIDITY VALUES OVERNIGHT WILL GENERALLY BE IN THE 50 TO 80 PERCENT RANGE...WITH VALUES DECREASING IN THE AFTERNOON HOURS INTO THE 25 TO 45 PERCENT RANGE. && .AVIATION...MORNING CLOUD COVER HAS ERODED AWAY...WITH PARTLY CLOUDY SKIES AREA WIDE. SCATTERED THUNDERSTORMS HAVE DEVELOPED OVER THE HIGHER TERRAIN AND WILL SLOWLY SPREAD WEST INTO THE LOWER DESERTS THIS AFTERNOON AND EVENING. OUTFLOW WIND GUSTS IN EXCESS OF 40KTS AND SMALL HAIL LIKELY WITH THE STRONGEST THUNDERSTORMS. DURING LATE NIGHT AND EARLY MORNING HOURS SUNDAY EXPECT SCT-BKN 15-25KFT MSL CLOUD BASES FROM PREVIOUS CONVECTIVE ACTIVITY. AVIATION DISCUSSION NOT UPDATED FOR TAF AND TWEB AMENDMENTS. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. && DISCUSSION...MOLLERE FIRE WEATHER/AVIATION...SHOEMAKER WEATHER.GOV/TUCSON
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE TUCSON AZ 437 AM MST SAT JUL 21 2007 AZZ019-029>035-221100- NORTHERN GREENLEE COUNTY-SOUTHEAST PINAL COUNTY- UPPER GILA RIVER VALLEY-WESTERN PIMA COUNTY-TOHONO OODHAM NATION- TUCSON METRO/MARANA/GREEN VALLEY-SANTA CRUZ COUNTY-COCHISE COUNTY- 437 AM MST SAT JUL 21 2007 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTH CENTRAL ARIZONA AND SOUTHEAST ARIZONA. .DAY ONE...TODAY AND TONIGHT EXPECT SCATTERED THUNDERSTORMS TO DEVELOP AGAIN THIS AFTERNOON OVER THE HIGHER TERRAIN AND MOVE INTO THE VALLEYS. SOME THUNDERSTORMS MAY APPROACH SEVERE LIMITS LATER THIS AFTERNOON AND THIS EVENING...WITH THE MAIN CONCERN BEING DAMAGING WIND AND HAIL. HEAVY RAIN IS ALSO POSSIBLE WHICH MAY PRODUCE LOCALIZED FLOODING. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.
The Tucson radar (KEMX), 141 km away, was scanning. The volume nearest the first event began at 21:59 UTC.
4 flash flood, 2 thunderstorm wind. Local standard time, as filed.
Three large pine trees were uprooted and power lines were knocked down due to strong winds from thunderstorms.
Two people were rescued from rising floodwater on Border road west of Douglas after their car overheated.
Flash flooding occurred in Wards Canyon in Clifton. 2 feet of mud and rock was mucked out from under the Wards Canyon bridge. In addition, two vehicles were stuck in soapbox wash.
Flooding and debris occurred along 8th street in Safford due to Flash Flooding. In addition, Klondyke Wash west of Safford was impassible.
Two mobile homes were destroyed and a traditional home partially destroyed in the Ventana Section of the Tucson Foothills. There were two uprooted trees at Grant Road and Kolb Road in Tucson and an estimated 60 mph gust due to thunderstorms in Tucson. A roof also collapsed at a furniture store near 22nd street and Wilmot road. In addition, these thunderstorms knocked down about 20 power poles near Palo Verde Road and Irvington Road. There were 18,000 customers without power in the Tucson area.
Flooding of the wash at 22nd street and Wilmot Road occurred after one to two inches of rainfall in the Tucson area.
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, July 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: 37137, 37153, 37150, 37134, 37140, 37143.