Antarctica

Weather Underground Forecast for Friday, November 21, 2008.

Northwesterly winds blowing across the Great Lakes will provide lake effect snow for parts of the Upper Midwest, Michigan, and the Ohio Valley that are closest to the lakes on Friday. Pennsylvania and New York will also be affected by the lake effect snow during the day. Several lake effect snow watches and warnings have been issued throughout the entire area, and several inches of snow is expected where the snow will be the heaviest. These watches and warning are set to expire at various times throughout the day. Elsewhere across the Northeast, relatively low pressure will bring partly cloudy skies and possibly a few scattered flurries to New England. Meanwhile, the Mid-Atlantic states can expect some snow showers due to a weak trough over the region. Most of the region will receive an inch or two of snow, although around four inches is expected in parts of West Virginia, Virginia, and western North Carolina.

A trough will move in over the Northern Plains from the west during the later afternoon or early evening hours on Friday, bringing gusty winds and snow to the area. Snow accumulations of no more than an inch or two are expected during the day. Meanwhile, a strong ridge over the rest of the Plains will keep conditions there dry and cold, with temperatures only expected to reach the 30s and 40s and the cold air extending as far south as Texas.

The high pressure will extend into the Southeast on Friday, keeping that region dry as well.

The trough that will move into the Northern Plains will first trek across the Northwest during the first half of the day on Friday. Snow showers are expected, although no significant snow accumulation is likely anywhere in the region, except for possibly areas in higher elevations. To the west, clouds and precipitation will move over the Pacific Northwest in the afternoon due to an advancing cold front.

The Southwest will generally remain dry and mild on Friday.

Temperatures in the Lower 48 states Thursday ranged from a low of -7 degrees at Mt. Washington, NH to a high of 87 degrees at Imperial, Calif.