* Some icy spots possible this morning from overnight periods of freezing rain, sleet and snow that moved across much of Southwest Virginia.
* Additional rain begins later today — possibly wintry mix to start — and continues overnight as milder air aloft overrides cold air at surface ahead of a low-pressure system moving into the Ohio Valley. More than 1 inch of rain possible.
* Rain expected to change to snow from west to east in the pre-dawn hours as cold air is pulled toward new developing low in North Carolina.
* An area of heavy snow develops on northwest side of low-pressure system on Wednesday. Where exactly it sets up difficult to pinpoint. General thinking based on forecast model output is that the edge of it extends southward to just north of the U.S. 460 corridor (Blacksburg-Roanoke-Lynchburg).
* Projected snowfall amounts generally 4+ inches in winter storm warning area north of Roanoke; 2-4 inches in winter weather advisory, Roanoke-New River Valley and southward.
* Snowfall amounts will shift upward if (1) cold air to support snow develops or remains in place much farther south than expected this evening; (2) cold air moves in faster in the pre-dawn hours; (3) the snow area on Wednesday extends farther south than modeled. A slight shift southward in the low’s projected track near Virginia-North Carolina border could result in more/wider snow coverage in Southwest Virginia on Wednesday.
* Snowfall amounts will shift downward if precipitation moves out faster than cold air can arrive in early morning and edge of snow area behind low is farther north than expected. A slight shift northward in the low’s projected track, moving further into southeastern Virginia, could result in lesser snowfal coverage/amounts for our region.
* Upslope snow showers on northwest winds develop mainly west of Blue Ridge Wednesday afternoon into Thursday monring, possibly adding to snow amounts in locations that usually receive snow squalls, especially west of I-77 and near Virginia-West Virginia border.
* Strong wind gusts exceeding 50 mph possible behind departing low late Wednesdsay/early Thursday.
* Warming trend with highs possibly topping 60 by weekend.