A strong ridge of high pressure aloft lingered over California and the Desert Southwest the first 3 days of the month, keeping the central and southern San Joaquin Valley under triple-digit heat. A monsoonal flow triggered thunderstorms over the mountains and the Kern county deserts, and one thunderstorm near Rosamond on September 1st spawned a tornado that moved through the town; a National…
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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 HNX wrote it up.
A strong ridge of high pressure aloft lingered over California and the Desert Southwest the first 3 days of the month, keeping the central and southern San Joaquin Valley under triple-digit heat. A monsoonal flow triggered thunderstorms over the mountains and the Kern county deserts, and one thunderstorm near Rosamond on September 1st spawned a tornado that moved through the town; a National Weather Service storm survey rated the tornado at EF0 on the new Enhanced Fujita scale. As the thunderstorm collapsed, it generated high winds that knocked down several power poles and created areas of blowing dust. Other thunderstorms in the same complex dropped -inch hail on the town of Boron in the southeastern corner of Kern county, generated a wind gust measured at 83 mph at the Mojave Air and Spaceport, and caused flash flooding in the vicinity of Mojave and California City.
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 Hanford, CA wrote its last area forecast discussion before the first event at Sep 1, 1:47 PM PST, 1 hour 20 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD CA 247 PM PDT SAT SEP 1 2007 .DISCUSSION...CLOUDS CONTINUE BUILDING OVER THE HIGHER ELEVATIONS AS CONVECTION FLAIRS UP AGAIN THIS AFTERNOON. YET...WITH THE FLOW ALOFT MORE WESTERLY TODAY...WILL KEEP CONVECTION CONFINED TO THE MOUNTAINS AND POSSIBLY THE DESERTS. WILL MAINTAIN PRECIP POTENTIAL AT SLIGHT CHANCE LEVELS AS INSTABILITY REMAINS WEAK THIS AFTERNOON. HOWEVER...AS MODELS MAINTAIN HIGHER LAYER PRECIPITABLE WATER VALUES OVER THE SOUTHERN SECTIONS OF THE DISTRICT...CAN NOT RULE OUT POSSIBLE THUNDERSTORMS. CURRENT 24 HOUR TREND STILL SHOWING VERY LITTLE CHANGE IN TEMPERATURES WITH DEW POINTS RUNNING SLIGHTLY LOWER. AT THE 850MB LEVEL...TEMPERATURES ARE EXPECTED TO REACH THE 25-27 DEC-C RANGE ON SUNDAY. THIS WILL TRANSLATE IN SURFACE READINGS ONCE AGAIN REACHING THE 100 TO 108 DEG-F RANGE. YET...DEW POINTS ALONG WITH TEMPERATURES ARE JUST MAKING THE RANGE OF PRODUCING HEAT ADVISORY CRITERIA INDICES. THEREFORE...WILL MAINTAIN THE HEAT ADVISORY FOR TONIGHT AND INTO SUNDAY. AFTER SUNDAY...MODELS PROG A WEAK TROF WILL APPROACH THE PACIFIC NORTHWEST. CURRENT TIMING AS THE TROF AXIS OVER THE REGION ON TUESDAY. THIS TROF IS PROGGED TO BE PROGRESSIVE AND WILL PASS QUICKLY INTO THE ROCKIES BY WEDNESDAY. YET...MAY SEE A GRADUAL COOL DOWN /SLIGHT/ EARLY NEXT WEEK. THE FLOW BECOMES MORE NORTHWESTERLY BEHIND THE TROF WHICH MAY KEEP THE DISTRICT COOLER THROUGH THE REST OF THE WEEK. IN ADDITION...THE NORTHWEST FLOW ALOFT WILL MAINTAIN A DRY FORECAST AFTER TROF PASSAGE. && .AVIATION...ISOLATED SHOWERS AND THUNDERSTORMS WILL PRODUCE LOCAL MOUNTAIN OBSCURATIONS ACROSS THE SOUTHERN SIERRA NEVADA THROUGH 05Z SUNDAY. OTHERWISE...VFR CONDITIONS CAN BE EXPECTED THROUGH 00Z MONDAY. FOR SPECIFIC DETAILS...PLEASE REFER TO THE TAFS FOR KMCE...KFAT AND KBFL...AND TWEB ROUTES 421 AND 423. && .AIR QUALITY ISSUES...NONE && .HNX WATCHES/WARNINGS/ADVISORIES...HEAT ADVISORY UNTIL 7 PM PDT SUNDAY FOR THE CENTRAL AND SOUTHERN SAN JOAQUIN VALLEY AND THE ADJACENT FOOTHILLS /CAZ089>094/. && PUBLIC...MOLINA AVN/FW...DCH WEATHER.GOV/HANFORD
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD CA 601 AM PDT SAT SEP 1 2007 CAZ089>094-021315- WEST CENTRAL SAN JOAQUIN VALLEY-EAST CENTRAL SAN JOAQUIN VALLEY- SOUTHWESTERN SAN JOAQUIN VALLEY-SOUTHEASTERN SAN JOAQUIN VALLEY- MARIPOSA MADERA AND FRESNO COUNTY FOOTHILLS- TULARE COUNTY FOOTHILLS- 601 AM PDT SAT SEP 1 2007 THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE CENTRAL AND SOUTHERN SAN JOAQUIN VALLEY AND THE ADJACENT FOOTHILLS. .DAY ONE...TODAY AND TONIGHT A HEAT ADVISORY IS IN EFFECT FOR TODAY FROM 2 PM UNTIL 7 PM. PLEASE REFER TO THE LATEST WEATHER MESSAGE ISSUED BY THE NATIONAL WEATHER SERVICE OFFICE IN HANFORD AT /WWUS76 KHNX/ OR /SFONPWHNX/ FOR FURTHER DETAILS. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY A HEAT ADVISORY CONTINUES FOR SUNDAY FROM 2 PM UNTIL 7 PM. PLEASE REFER TO THE LATEST WEATHER MESSAGE ISSUED BY THE NATIONAL WEATHER SERVICE OFFICE IN HANFORD AT /WWUS76 KHNX/ OR /SFONPWHNX/ FOR FURTHER DETAILS. .SPOTTER INFORMATION STATEMENT... WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS TO THE SAN JOAQUIN VALLEY NATIONAL WEATHER SERVICE OFFICE. WEATHER.GOV/HANFORD JEB
The national radar mosaic for the moment the first event began.
2 thunderstorm wind, 1 funnel cloud, 1 tornado, 1 flash flood. Local standard time, as filed.
Public reports of a funnel cloud were relayed through the Sheriff's Office between Rosamond and Lancaster. This is the storm that produced an EF0 tornado in the Rosamond area shortly thereafter.
Official NWS damage survey determined that an EF0 (Enhanced Fujita) tornado touched down about 3 miles southwest of Rosamond...then traveled north through Rosamond and northeast to about 3 miles southeast of Mojave. This tornado had estimated wind speeds of 65-85 mph. The first touchdown occurred near the intersection of Avenue A and 40th Street West, which is about 3 miles southwest of Rosamond. Minor property damage occurred in this area with several fences blown over and small trees and branches downed. The tornado then traveled north to around Rosamond Blvd, where numerous utility poles were blown over, branches were downed and some miscellaneous debris was found. The path then curved northeast and crossed Highway 14 near Dawn and Backus Roads and Sierra Highway. Damage in this area amounted to some property damage to several mobile homes. Minor debris was found a few miles southeast of Mojave, which is the area that the tornado dissipated.
A trained weather spotter reported a power pole on a house on 53rd Street on the west side of Rosamond. These winds were associated with the severe thunderstorm that spawned a tornado nearby.
A damaging wind gust, in association with a severe thunderstorm, was report at the Mojave Spaceport with data from the Edwards Weather System wind tower.
Local law enforcement reported Highway 14 flooded in both directions near the intersection of California City Blvd. Flooding was also occurring around the Mojave Airport.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2007Every state in 2007This day in weather historyThe tornado archive for California, 2007Warnings in California, September 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: 61503, 61502, 61504, 61508, 61507.