2008: A tornado was observed over Johnson Valley (east of Apple Valley), but no damage was reported.
2000: Big Sur had a high temperature of 91° F.
1996: Mount Charleston (northwest of Las Vegas, NV, near CA-NV border) recorded a low temperature of 17° F. This tied the record for the all time coldest low temperature in September.
1984: A tropical air mass lasting two weeks and high sea surface temperatures led to record minimum temperature records set each day except one at San Diego starting on 9.4 and ending on 9.19.
Low temperatures ranged from 73° F to the highest minimum of all time of 78° F on this day and on 9.9.
The high was 100° F on 9.8.
1982: The remnants of Hurricane Norman tracked northeastward across northern Baja California into Arizona with scattered rainfall amounts up to one inch in the southern mountains and deserts on this day and on 9.18.
This occurred during the strong El Niño of 1982-83.
1965: The morning low temperature at Reno, NV was 23° F.
1963: Northeastward moving Tropical Storm Katherine made landfall in northern Baja California with rainfall of up to 6.50" in the mountains from this day to 9.19.
3.86" fell in San Bernardino, 3.44" in Riverside, 2.66" in Victorville and Cuyamaca, 1.90" in San Diego, 1.88" in Indio, and 1.62" in Santa Ana.
Disastrous flooding and erosion hit a northern San Bernardino neighborhood.
1963: Remnants from Tropical Storm Katherine move into western Arizona.
2.42" of rain is observed in Yuma, AZ, causing severe damage to cars, homes, and businesses. Severe losses to Cotton/Alfalfa/Lettuce crops
1957: Fresno recorded 0.19" of rain on this date.
This made September 1957 the wettest September in Fresno in 27 years.
1929: A tropical air mass enveloped Southern California.
The Meteorologist in Charge at San Diego reported temperatures of 111° F in the coastal valleys on 9.16.
A reading of 94° F was at San Diego at 4 am on this day.
1913: Santa Ana conditions produced a high of 110° F at San Diego, which was the all time record high temperature until 9.26.1963 (when it hit 111° F).
An unofficial report of 127° F came from San Bernardino.
One died, a carpenter working outside.
A few small fires occurred, including one downtown that destroyed one house.
Santa Barbara established an all-time high of 108° F.
Source: NWS San Francisco/Monterey, Hanford, Reno, Las Vegas, Phoenix, & San Diego