Rainfall May Be Getting Back to Normal After Dry Spell

A spate of rain Monday afternoon -- and a chance of more this afternoon -- may signal things getting back to normal in Southern California after an unusual winter dry spell.

Monday’s showers scattered up to about one-quarter of an inch of rain as they moved slowly across the area in a narrow band in the afternoon and evening. The storm brought a “secondary disturbance” in its wake, which might produce some scattered showers near the mountains later today, said James Murakami, staff meteorologist with the Atmospheric and Oceanic Sciences Department at UCLA.

All told, however, this storm pattern is proving to be weaker than first thought, and the chances of any rain today in downtown Los Angeles are slim -- about 20%, Murakami said.

Monday’s storm originated in the Gulf of Alaska and expended most of its force over Northern California before hitting West Los Angeles about 2 p.m. Monday.

As it moved over Sonoma County on Sunday, it pushed rising water through an existing hole in a levee that had gone unrepaired since January. Some agricultural land and a two-lane county road were flooded, authorities said.

For Los Angeles, the early-March squall marked a change from the three preceding months. December, January and February were much drier than usual, a sharp contrast to last year, when L.A. recorded its second-wettest year ever.

Despite the dry months, enough rain fell Monday, and in brief storms in early fall and the end of December, to keep the Southland near median rainfall levels, Murakami said.

He said that rainfall at UCLA has been about 60% to 70% of the average for this time of year, but that this is not unusual since the median is usually lower than the average, which is skewed by the occasional extremely wet year.

In short, this rainy season stands out only for its lack of distinction.

Murakami summed it up as “a mediocre pattern” -- likely to end up a little drier than the average, but still close to normal.

Part of the reason there has not been more rain is that this is a La Nina year, which typically corresponds to lackluster storms in Southern California, he said.

La Nina refers to a colder than average ocean current in the Pacific Ocean west of Peru. It favors a jet stream that tends to drive storms to the north. El Nino, a warmer than average current, tends to do the opposite, producing wetter weather in Southern California.

Another storm is heading toward Southern California this week and is expected to hit Friday or Saturday -- or perhaps as late as Sunday, Murakami said.

The nature of this storm remains highly uncertain, he said.

Some models are predicting it will bring more rain, but most are not. More likely, he said, it will be “a dry, cool, windy storm.”