A Sunny Respite Could Be the Calm Before New Storm

March’s wintry barrage subsided Thursday, as the latest storm, which flooded streets, snarled traffic and closed mountain schools in San Diego County slowly made an exit, leaving sunny, cool weather in its wake.

But picnickers should gather their baskets by Saturday afternoon, as clouds heralding what could be a power-packed storm bigger than those earlier in the week begins to roll in, arriving Sunday and lingering till Tuesday, forecasters predict.

“The storm is coming in with a very intense low-pressure center,” National Weather Service forecaster Wilbur Shigehara said. “It should begin to pack some punch.”

This week’s storms dropped 2.89 inches of rain at Lindbergh Field, making this month the 13th wettest March on record, Shigehara said.

Temperatures dipped to 47 degrees Thursday morning, and strong winds spawned a twister sighted by an airline pilot over the ocean at 5:30 a.m. off Mission Bay.

Cars crept across an icy Interstate 8 Thursday night, hampered by snows that closed the freeway to one lane in each direction between Japatul Road and the Imperial County line, California Highway Patrol spokesman Joe Roque said.

Dehesa Road was washed out near Japatul Road, and chains were required in mountain areas, Roque said.

In Mission Valley, the swollen San Diego River overran its banks, flooding parking lots and closing roads, a spokesman for the San Diego Lifeguard Service River Rescue Team said.

The river’s fast-moving waters quickly filled pipe outlets and spilled over onto roadways crossing the path of the river, lifeguard Lt. Brant Brass said. Fashion Valley Road and Camino de la Reina were still closed as of early Thursday evening.

Lifeguards have rescued half a dozen motorists in the past two weeks who failed to heed barricades and stalled in surging waters, Brass said.

Heavy snow closed schools in mountain areas, giving students at Palomar Mountain School an early start on spring break, Pauma School District Supt. Kim McLaughlin said. The administration canceled classes Thursday and today, and school will not resume until April 1.

“The snowdrifts were just too high,” McLaughlin said. “We had cars buried under them, and the power was out this morning.”

Snow levels dropped to 2,500 feet overnight, bringing snow to foothills in San Diego and the desert communities of Campo and Boulevard, Shigehara said.

The storm interrupted power service to more than 17,500 customers in the county, San Diego Gas & Electric spokeswoman Elizabeth Pecsi said.

“The snow was so heavy in the backcountry areas, like Campo and Boulevard, that it has knocked down the wires,” she said.

Mt. Laguna, the only mountain area that weather forecasters could reach, had 32 inches of snow on the ground.

Rainfall in other parts of the county were: La Mesa 1.98 inches, Lemon Grove 1 inch, Fallbrook 0.49 of an inch, Santee 1.23 inches and National City 0.80 of an inch.

Although the storm off the Gulf of Alaska appears small now, it will gather strength from other storms in the Pacific and intensify as it approaches San Diego over the weekend, Shigehara said.

The storm is expected to be colder than those that hit San Diego this week, and could drop snow levels to as low as 1,500 feet.

A strong low-pressure center will cause the storm to linger several days and could end up dropping 1 to 2 inches of rain on an already saturated San Diego, causing urban flooding and mudslides, Shigehara said.

“It will get colder and colder Sunday and Monday, setting off thunderstorms, funnel clouds and tornadoes,” Shigehara said. “The potential is there. It can linger into Tuesday and bring wave after wave of rain. It will creep through and behave like more like a hurricane.”

Thursday’s storm brought rainfall for the season to 9.16 inches, surpassing the normal level for this date by 1.4 inches.

“March came in like a lion,” Shigehara said. “And let me tell you, the lion is still roaring.”