Weather Underground Forecast for Friday, February 13, 2015

A Pacific system will move over the Northwest on Friday, while a separate system will develop over the Great Lakes.

An area of low pressure will sink southeastward over the Great Lakes. This system will usher light to moderate snow showers over parts of the northern Plains and the upper Midwest on Friday. Just to the east, an arctic high pressure system will slide across the Northeast. Bitter cold arctic air will impact the northern Mid-Atlantic and New England. Wind chill warnings are in place for northern Pennsylvania, New York and northwest New England. In addition, this cold air mass will interact with the relatively warm waters of the Great Lakes. This interaction will generate lake effect snow over portions of Upstate New York. High pressure will continue to bring a mild weather pattern to the Deep South and the Southeast.

Out west, a Pacific low pressure system will approach the Pacific Northwest. A cold frontal boundary associated with this system will initiate light rain over western Oregon and Washington. By the afternoon and evening, a mixture of rain and snow will spread eastward over the northern Rockies. A ridge of high pressure will keep conditions warm and dry across the Great Basin and the Southwest on Friday. Temperatures are forecast to range between the 70s and 80s across the Desert Southwest.

Temperatures in the Lower 48 states Thursday have ranged from a morning low of -27 degrees at International Falls, Minn. to a high of 87 degrees at Santa Ana, Calif.