SAN DIEGO -
The first storm of autumn brought cooler temperatures and modest, scattered rainfall to the San Diego area Thursday.
*Click here to see viewer-submitted photos of rain and rainbows around San Diego County
The unsettled system out of the Pacific Northwest began dousing the region with light showers in the mid-morning, according to the National Weather Service.
The precipitation continued throughout the day, gradually dissipating in coastal communities as the clouds drifted eastward.
The moisture totals across the county varied widely, with some locales collecting fairly significant amounts while others got traces at most, the NWS reported.
John Choi was at work at a flower shop in Del Mar and was one of many caught off guard by Thursday's weather.
"I was caught pretty unprepared," Choi said. "I'm wearing shorts and sandals."
Ally Wickersham was talking a walk nearby when the storm struck.
"I'm really soaked right now," Wickersham said. "I didn't wear the proper attire. Flannel does not suffice when it's down-pouring."
The wind whipped around as the storm barreled in off the coast. It pounded the North County first.
When the rain started to fall, the cars started to crash.
"We had two crashes this morning at about the same time at this location," Jason Peterson of California Highway Patrol said on Interstate 15 near Interstate 8. "One was on the northbound side, which was this semi truck and the other was on the southbound side."
The twisted truck was no match for Mother Nature as it slid across all lanes on I-15 and smashed into the center-divide. The front of the truck was 200 feet away. The dangers of driving were crystal clear amid a whirlwind of elements.
Hail slammed the San Marcos area, and a viewer captured what appeared to be a waterspout in the skies over Coronado.
"It was crazy," Choi said. "I had to get all my flowers in and it was crazy. It just came down in a split second and was sunny a couple seconds before that."
While Choi rushed to get indoors, others rushed out to see the rain, and the rainbows that followed.
Over a 12-hour period ending at 5:30 p.m. the storm dropped 0.7 of an inch of rain in northern Poway, 0.65 in Oceanside, 0.45 at Ramona Airport, 0.39 at Lake Wohlford, 0.3 in Fallbrook, 0.16 at SeaWorld and 0.09 at Lindbergh Field.
The showers should dwindle further tonight before ceasing entirely sometime Friday morning, making way for clearing skies, NWS meteorologist Tina Stall said. The weekend is expected to bring a gradual warming trend along with fair weather, she stated.