2013: An upper-level low approached the California coast on the 19th, drawing very warm air into the central California interior from the south. Temperatures climbed to their highest readings of the month, with Fresno reaching 110° F, and Bakersfield hitting 108° F.
Thunderstorms developed over the mountains and deserts, with some drifting into the San Joaquin Valley during the afternoon and evening hours.
Thunderstorms dropped heavy rain (1.90") which caused flash flooding on highway 178 at the mouth of the Kern River Canyon.
Local CHP reported rocks and mudslides blocking Highway 178 at the Mouth of the Kern Canyon.
The road was shut down for several hours.
Several vehicles were stuck in the canyon.
An early afternoon thunderstorm dropped 1/4" hail near Lake Isabella.
An early evening thunderstorm dropped 1/4" hail on Fresno.
Outflow winds from collapsing thunderstorms caused roof damage east-southeast of Lemon Cove, and a 30-foot flag pole was blown over.
Trees and utility lines were downed in Woodlake.
In the Southern Sierra Nevada foothills, 50 mph winds damaged fences in the town of Dunlap, northeast of Squaw Valley, and downed trees and utility lines in Springville.
High winds also brought down a 30 foot flag pole and caused roof damage 2 miles ESE of Lemon Cove.
A flash flood caused road closures at US 395 and Garlock/Redrock Randsburg Roads.
Roads were closed in Ridgecrest due to flooding near the Intersection of US 395 and Brown Road.
State Highway 14 also closed.
Record high maximum and minimum temperatures were also reached.2003: Reno, NV had a high temperature of 99° F.
2003: A thunderstorm produced intense rainfall over the northwest portion of the Las Vegas valley with several automated and personal rain gauges recording between 3"-5" of rain in less than an hour.
Many roads became completely impassable with nearly 60 swift water rescues being performed.
Several homes and businesses were severely damaged from flooding including the local chapter of the American Red Cross.
Highway 95 was closed between Rainbow and Jones for several hours after becoming completely submerged.
Total damages were estimated at $2 million.
2001: The Highway Fire 2 miles east of Dunlap (Fresno Co.) is suspected to have been caused by arson.
It burned 4,152 acres and forced the evacuation of a large number of residents.
There were no fatalities, but 8 structures were lost (3 primary and 5 out-buildings).
Total cost to contain was over $6 million.
1997: The remnants of tropical storm Ignacio produced record rainfall over portions of northern and central California.
24 hour and 1 hour rainfall records were exceeded at San Francisco, and it was the second wettest August ever recorded in the City.
General rainfall totals ranged from 0.5 to 1.5" in the northern San Francisco Bay Area with 0.5 to 2.27" farther south along the immediate coastal range.
Along the central coast, Three Peaks in the Santa Lucia Mountains of Monterey County had a rain rate of just over 0.9" an hour and a 24 hour total of 2.2".
The greatest hourly rainfall rate at San Francisco Duboce Park was 0.22" between 11 pm and midnight on August 19, which set a record one hour maximum rainfall rate for August.
1997: Tropical Storm Ignacio produced a large southerly swell that had SoCal beaches in its sights starting 8.17 to this day.
The resulting surf at area beaches was extreme with sets to 18 feet along the Orange County coast.
1997: A gradient wind (non-thunderstorm) with speeds at 40 MPH plus was caused by the old center of Hurricane Ignacio moving over the San Joaquin Valley.
Arsonist started blazes, named the "Chocktaw Fire," pushed into homes northeast of Bakersfield and two were destroyed with 4 others damaged with 4,000 acres charred.
One firefighter was burned while fighting the fire.
The damage cost was estimated at $400,000 acres.
This same wind also was responsible for starting a fire in the Tehachapi Mountains by arcing power lines.
1,151 acres were burned in the"Comanche Fire" located 10 miles WSW of Tehachapi.
Points 8 miles east to 17 miles south of Bakersfield in the Southern San Joaquin Valley also experienced visibilities to near zero in blowing dust from this event.
Numerous minor traffic accidents occurred but no injuries or fatalities were reported from California Highway Patrol.
Damage costs for the blowing dusts were estimated at $100,000.
Crop damage may have occurred but not assessable by the County Ag Commissioner.
1983: The lowest maximum temperature on record of 74° F in Riverside remarkably occurred on the same day as the highest minimum temperature of 70° F for this day.
1976: Fresno only reached 67° F for a high temperature.
This is not only the coldest high temperature on record for the month of August, but also the earliest in the season that Fresno has had a high temperature in the 60s.
1973: Late in the evening a severe thunderstorm developed over El Centro and produced a downburst with winds near 70 mph.
Damage was extensive with around 100 power poles snapped, roofs ripped from buildings, numerous trees down, and hay bales blown apart.
1967: A violent hail and rain storm caused flash flooding that carried tons of rock and gravel onto U.S. Highway 95, between Las Vegas and Searchlight, NV, forcing the highway to close for four hours.
Winds during the storm, 15 miles north of Searchlight, reached gale force. Hailstones the size of half-dollars fell and rainfall measured close to 1" in 22 minutes.
1961: Thunderstorms hit Barstow, Redlands and Calimesa.
Roads and highways were eroded.
A few homes in Redlands were sitting in 2'-3' of water.
1959: It was 31° F in Idyllwild, making this the earliest date in the season to reach freezing temperatures.
1945: What is believed to be a decaying tropical storm hit the region on 8.18 and this day.
1.75" of rain fell in Escondido on this day, the greatest daily amount on record for August.
1906: Bakersfield ended a run of 50 consecutive days with highs of 100° F or better.
This is the longest such streak on record here.
1906: A tropical storm came up into the Gulf of California and the southwestern United States, giving the mountains and deserts heavy rainfall on 8.18 and on this day.
Needles received 5.66" of rain, twice the normal of seasonal rainfall with 3.49" falling in 24 hours, the highest one-day rain total there ever.
This occurred during the El Niño of 1905-06.
Source: NWS San Francisco/Monterey, Hanford, Reno, Las Vegas, & San Diego