Winter Storm Cleon Targets Western U.S

The Weather Channel has named Winter Storm Cleon, the third named winter storm of the 2013-14 season. Cleon will usher in a period of very cold weather across much of the western and northern U.S., along with zones of significant snowfall.

Let's start with the outlook for snow and ice, beginning in the Northwest. Snow levels will drop Sunday night as a Pacific cold front slides into the Pacific Northwest, bringing snow to lower and lower elevations within the Cascades, Bitterroots, and Tetons through Monday.

Given the trajectory of the attendant upper-level trough diving more toward the south and southeast into the West, cold Arctic air will be pulled not only down the Front Range of the Rockies, but also into the Great Basin and even into the I-5 corridor of western Washington and western Oregon. Thus, a few snow showers are possible even in these low elevations starting Monday.

Before the cold air arrives, heavy rainfall could lead to some localized flooding problems, particularly in western Washington where flood watches have been issued.

The snowfall will create significant impacts to travel through the mountain passes including Sherman Pass in northeast Washington and Stevens and Snoqualmie Passes in the Cascades. Several inches of snow will be likely in the passes with well over a foot at higher elevations of the Cascades through Bitterroots through Monday. Seattle and Portland could see some snow mix in with rain as early as Monday, mainly on the higher hills.Tuesday into Wednesday, the deep upper-trough and cold front continue plowing south, spreading snow into the Sierra Nevada, Wasatch and Rockies. While this is happening, another broad area of potentially heavy snow and pockets of mixed wintry precipitation may develop behind the Arctic front in the High Plains of Montana and Wyoming, spreading into parts of the Northern Plains and Upper Midwest.

http://www.weather.com/news/weather-winter/winter-storm-cleon-forecast-20131201