A complex weather pattern will set up over the Midwest and the Mid-Atlantic on Wednesday, while a Pacific system brings widespread mountain snow to the Northwest.
A low pressure system will move northeastward from the central Plains to the lower Great Lakes. This system will produce gusty winds and mixed precipitation. As a warm air mass overruns a colder air mass, a mixture of rain, freezing rain and and snow will develop from the upper Midwest to the northern Mid-Atlantic.
Freezing rain will be a particular concern for portions of Pennsylvania and southern New York. A cold frontal boundary will stretch south southwestward from the middle Mississippi Valley to the southern Plains. As this frontal boundary transitions eastward, it will initiate rain and thunderstorms across the middle Mississippi Valley, the lower Mississippi Valley, the western Gulf Coast and the Tennessee Valley.
Most of the Southeast should stay clear of precipitation, with the exception to scattered showers along the east coast of Florida.
Meanwhile, a Pacific cold frontal boundary will extend south southwestward from Washington to northern California. As this frontal boundary pushes east southeastward, it will produce periods of moderate rain and mountain snow in the Pacific Northwest, northern California, the Great Basin and the Intermountain West. Locally heavy snow will be possible in the northern Cascades. Most areas from southern California to central Texas will be dry on Wednesday.
Temperatures in the Lower 48 states Tuesday have ranged from a morning low of 1 degrees at Marshfield, Wis. to a high of 88 degrees at Edinburg, Texas