‘Pineapple Express’ Due to Arrive This Weekend

The “Pineapple Express” is expected to roll through Southern California this weekend, but meteorologists say tropical rains forecast for Saturday and Sunday generally will be moderate and no major problems are anticipated.

The main body of the storm should pass north through Oregon, with only about a half-inch to an inch of rain expected in downtown Los Angeles, according to Jeff House, a forecaster with WeatherData Inc.

“This one has more bark than bite,” House said.

The approaching storm is not related to the much-discussed El Nino phenomenon. “This sort of thing could happen any year,” House said.

“But the El Nino pattern is still here,” he added. “January and February should still be wetter than normal. Rain lovers probably will get their chance in coming weeks.”

The storm due this weekend was centered several hundred miles off the coast Wednesday, its eastward movement blocked by high-pressure systems stalled over California. As it sits there, the storm is pulling in tropical moisture from equatorial waters south of Hawaii--moisture that will start falling as rain along the West Coast when the high pressure begins to dissipate late Friday.

“Fortunately, there aren’t that many thunderstorms in the tropics right now, so there isn’t as much moisture as there might have been,” House said. “In addition, the high pressure has been pushing the system to the north, toward Oregon. California will get rain, but not in huge amounts--nothing as heavy as some of those storms earlier in the season.”

House said showers could start sprinkling the Southland as early as Friday night, with sporadic rain Saturday and Sunday. He said that although it is too early to forecast specific amounts, as much as two inches of rain could fall on some of the foothill communities surrounding Los Angeles, with a quarter to half that much in the coastal valleys.

Because of the infusion of tropical moisture, the storm will be relatively warm, meteorologists said. Weekend temperatures are expected to range between the low 40s and upper 60s, with snow levels as high as 7,000 to 8,000 feet.

The rain should end Sunday night, House said. Clearing skies and warmer temperatures are forecast for Monday.