'Pineapple Express' Storm Barrels Toward SoCal With First Halloween Rain In Decades – Patch

‘Pineapple Express’ Storm Barrels Toward SoCal With First Halloween Rain In Decades  Patch

Tropical moisture could fuel downpours across Southern California, with rain expected to peak Saturday night into Sunday. A weather pattern known as the “Pineapple Express” threatens to bring heavy rain to Southern California over Halloween weekend, potentially dampening trick-or-treating and causing flooding in some areas, forecasters said Thursday. Two Pacific storms could draw tropical moisture toward the western United States over Halloween weekend, with a third weather system near Hawaii potentially contributing to the developing pattern, according to AccuWeather. "A storm from Alaska and another off Washington's coast will draw tropical moisture into the western U.S. this weekend," AccuWeather Meteorologist Lydia Burroughs said. "Tropical Rainstorm Olana near Hawaii will help influence that moisture plume.

Rainfall amounts in Southern California will depend on how quickly the storms and moisture come together." The weather pattern could develop into an atmospheric river, a long band of concentrated moisture that can bring heavy rain and mountain snow. When that moisture stretches from near Hawaii to the West Coast, it is commonly called a Pineapple Express. However, AccuWeather said the more likely scenario would keep the storms and their moisture somewhat separated, limiting the heaviest rainfall around Los Angeles, San Diego and Palm Springs. Under that scenario, most major Southern California cities would receive less than an inch of rain, while some mountain slopes could