Several storm systems have been riding the Pineapple Express over the past few days, dropping copious rain and high elevation snow across the Pacific Northwest. The last storm is the series should arrive tomorrow, aggravating the mudslides and flooding that have plagued the region.
On the bright side, the moisture flow will shift south as the jet stream begins to dip across the Western U.S. and is expected to drop at least two feet of snow on the Sierra Nevada, welcome news for drought-stressed California. The developing atmospheric trough will also allow the Pacific Northwest to dry out and bring plenty of snow to the mountains (and ski areas) of Utah and Colorado.
Of course, potent storm systems have negative consequences as well. As warm, humid air is swept northward ahead of the trough, producing record highs from the Gulf Coast to the Upper Midwest, the atmosphere will be primed for severe thunderstorms. These storms, some of which may spawn tornadoes, will ignite along the cold front and are expected to boil up from Texas to the Great Lakes over the coming weekend. Behind the front, winter will return to the Heartland.
