Premium: Winter weather impacts in Northeast US this week

A dynamic storm system is expected to track through the Northeast United States later this week, bringing with it the opportunity for some frozen precipitation, particularly on the front end as the storm develops. This will be especially true in the interior and higher elevations, before warm air changes precipitation over to rain. Nearer to the coast, mostly rain is expected, although a brief burst of frozen precipitation isn’t out of the question in the suburbs and higher elevations there as well.

The storm system will be operating and gaining steam from “warm air advection” in the mid levels of the atmosphere. Moisture surging toward the Northeast US on Thursday will provide increasing lift for precipitation as warm air moves into the atmospheres mid levels. The atmosphere will quickly become too warm for frozen precipitation near the coast, but colder air will hang on a bit longer in the interior. This will lead to a complicated forecast.

The process occurring is not uncommon for the Northeast United States, especially early in the season. With a storm track over Southeast Canada, southwest winds in the mid levels of the atmosphere occur. But nearer to the surface, northeast winds hang on a bit longer with a departing high pressure system. This allows colder air to funnel down into the Northeast US, and keep frozen precipitation around a bit longer.

Snowfall accumulations will be very difficult to pin down as geographical differences will have a major impact. Elevation will certainly play a part, but the best areas for accumulation currently look likely to be Central New York State, the Vermont Green Mountains, and Northern Maine.

The storm may have particularly intense winter impacts in Northern Maine if the secondary surface low develops in the Gulf of Maine near Portland and then moves eastward. This would allow cold air and impressive dynamics to juxtapose in Northern Maine, leading to the potential for several inches of snow on Friday.

The storm will wrap up on Friday across most of the Northeast, but linger in North/Eastern Maine through Friday as the secondary low pressure area develops. Check out the video above, or the interactive map below, for the latest information from our team of forecasters.