Southwesterly flow prevailed over Arizona with a closed upper low located over south-central California. Enough moisture was present ahead of this system to cause isolated thunderstorms to develop during the afternoon that produced wind damage in Safford.
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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.
Southwesterly flow prevailed over Arizona with a closed upper low located over south-central California. Enough moisture was present ahead of this system to cause isolated thunderstorms to develop during the afternoon that produced wind damage in Safford.
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 Oct 4, 3:11 PM MST, 39 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TUCSON AZ 311 PM MST SUN OCT 4 2015 .SYNOPSIS...RAIN CHANCES WILL BE ON THE INCREASE LATER TONIGHT AHEAD OF A STRONG LOW PRESSURE SYSTEM OVER CALIFORNIA. EXPECT A GOOD CHANCE OF SHOWERS AND THUNDERSTORMS BY MONDAY AND TUESDAY...ALONG WITH MUCH COOLER TEMPERATURES AND GUSTY WINDS AT TIMES. SOME LINGERING SHOWERS WEDNESDAY AS TEMPERATURES FALL BELOW AVERAGE FOR EARLY OCTOBER. DRIER WITH A SLOW WARMING TREND LATE NEXT WEEK. && .DISCUSSION...A CLOSED UPPER LOW CENTERED OVER THE CENTRAL CALIFORNIA COAST EARLY THIS AFTERNOON WILL CONTINUE TO APPROACH THE AREA. MOISTURE STREAMING NORTHWARD AHEAD OF THIS SYSTEM WILL BRING INCREASING CHANCES OF RAIN STARTING TONIGHT. LATEST MODELS CONTINUED TO POINT TO MONDAY INTO TUESDAY AS THE MOST ACTIVE IN TERMS OF SHOWERS AND THUNDERSTORMS. THE STRONG UPPER DYNAMICS COUPLED WITH DAYTIME HEATING WILL RESULT IN SOME STRONG THUNDERSTORMS WITH THE THREAT OF HAIL AND STRONG WINDS BEING THE MAIN CONCERNS MONDAY AFTERNOON AND EARLY EVENING. MODELS TRACK THE UPPER LOW OVER CENTRAL AND SOUTHEAST ARIZONA ON TUESDAY WITH THE FOCUS FOR STRONG THUNDERSTORMS SHIFTING TO MAINLY EASTERN SECTIONS OF THE CWA TUESDAY AFTERNOON. SPC DAY TWO AND DAY THREE OUTLOOKS HAVE THE AREA IN MRGL SEVERE WITH SIMILAR TRENDS FROM MONDAY TO TUESDAY. BOTH THE GFS AND ECMWF WERE IN BETTER AGREEMENT WITH THE TRACK OF THE UPPER LOW THROUGH LATE WEDNESDAY. EVENTUALLY...THE MODELS SHOWED THE LOW MOVING EAST OF THE REGION THURSDAY EITHER INTO MEXICO OR SOUTHWEST TEXAS. THE SYSTEM WILL ALSO BRING COOLER DAYTIME TEMPERATURES THROUGH WEDNESDAY...WITH WEDNESDAY BEING THE COOLEST DAY. HIGH PRESSURE ALOFT WAS PROGGED TO NUDGE INTO THE REGION AROUND THURSDAY AND FRIDAY FOR DRY AND WARMER WEATHER. && .AVIATION...VALID THRU 06/00Z. SCT-BKN CLOUDS AT 6-10 KFT WILL CONTINUE THROUGH THE FORECAST PERIOD. ISOLD -SHRA/TS POSSIBLE NEAR ALL TERMINALS...WITH BEST CHANCES EAST OF KTUS THROUGH EARLY THIS EVENING. MINIMAL -SHRA COVERAGE OVERNIGHT...THEN ISOLD-SCT -SHRA/- TSRA EXPECTED TO DEVELOP MONDAY AFTERNOON WITH GREATEST CHANCES FROM KTUS EASTWARD. MEANWHILE...GUSTY SOUTHERLY SFC WINDS OF 12-18 KTS WITH GUSTS 20-25 KTS THROUGH SUNSET. WINDS WILL BECOME A BIT MORE SELY AND ABATE SLIGHTLY OVERNIGHT BEFORE INCREASING SOUTHERLY WINDS ONCE AGAIN AFTER 05/16Z. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...AN AREA OF LOW PRESSURE WILL BE IMPACTING SOUTHEAST ARIZONA OVER THE NEXT FEW DAYS. THIS SYSTEM WILL ALSO BRING INCREASED MOISTURE ALONG WITH A CHANCE OF SHOWERS AND THUNDERSTORMS THROUGH WEDNESDAY. A FEW STORMS COULD BE STRONG MONDAY AND TUESDAY AFTERNOON. OTHERWISE...EXPECT BREEZY SOUTHERLY WINDS...ESPECIALLY INTO THIS EVENING AND ONCE AGAIN MONDAY. TEMPERATURES WILL CONTINUE TO COOL DOWN WITH HIGHS BELOW NORMAL THROUGH MIDWEEK...THEN MODERATING LATER THIS WEEK. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. && VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
The Tucson radar (KEMX), 135 km away, was scanning. The volume nearest the first event began at 22:49 UTC.
1 thunderstorm wind. Local standard time, as filed.
A power pole was snapped off at the base. In another area, power lines were snapped and were dangling from their poles.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Arizona in 2015Every state in 2015This day in weather historyWarnings in Arizona, October 2015
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 2026-10-01. Each event’s entry at NCEI: 604355.