Afternoon Showers Bring Traffic Snarls : Weather: Three trucks and at least 12 other vehicles collide on rain-slicked Simi Valley Freeway. More rain is expected.

Winter made yet another springtime visit to the Southland on Tuesday, bringing scattered showers and cool temperatures to the San Fernando Valley. Meteorologists, blaming a deep trough of low pressure hovering over most of the Golden State, said similar weather is expected over the next two days.

The biggest problem caused by the intermittent showers Tuesday was a collision on the westbound side of the Simi Valley Freeway that involved three semi-trucks, an empty school bus and at least 11 other vehicles, according to the California Highway Patrol.

There were only minor injuries resulting from the accident that occurred near the San Diego Freeway interchange, but traffic was blocked for almost two hours while the many wrecks were cleared.

It started about 1:05 p.m., according to CHP Officer Jeff Ferber, when a semi-truck driving too fast for the rain-slicked road braked, skidded and “drove over” a pickup truck ahead of it. Other cars swerved to avoid the crash, Ferber said, with some crashing into each other.

Moments later another semi-truck approaching the scene could not stop in time and jackknifed over a Buick driven by a State Farm insurance adjuster, Ferber said.

A Volkswagen “Bug” slid into the second big rig and then a third semi-truck rear-ended an empty school bus that had stopped for the crash.

“It was a huge, huge mess,” Ferber said.

The three people who sustained injuries serious enough to be taken to Holy Cross Medical Center were all treated and released. Among them was a 2-year-old girl riding in the Volkswagen who suffered a hand laceration. She was thrown into the windshield when the car slid into the pileup, Ferber said.

Elsewhere, the Los Angeles Police Department’s Valley Traffic Division reported at least five rain-related accidents on surface streets that occurred during the afternoon shower.

As for today’s weather, there is a 30% chance of showers in the Los Angeles Basin and that will diminish to 20% by Thursday, said Curtis Brack, a meteorologist for WeatherData Inc., which provides weather information for The Times.

Although the chance of showers will continue to diminish throughout the week, Brack said, cloudy days are expected through the weekend.

On Tuesday, he said, up to 0.4 inches of rain fell in some parts of the Valley.

* INSECT ALERT: Late rains mean flea problems. B5