Snow and rain on the way to New England via major national storm

Gordon Weyaus (left) and Katy Little with dog Jax walked along Mandan Street in Bismarck, N.D. on Wednesday.Tom Stromme/The Bismarck Tribune via AP

There’s a large storm system swirling around the center of the country Wednesday afternoon, providing lots of precipitation in various forms.

The satellite image clearly shows the classic swirl of low pressure over the Dakotas with a trailing comma shape along the cold front reaching to the Gulf of Mexico. This is a dynamic and volatile weather situation.

Severe weather is occurring across the South, where tornado watches and warnings have been posted. There are blizzard warnings to the west of the storm and ice storm warnings to the east.COD Weather

This system is affecting millions of people across the United States and Southern New England will eventually come into the mix.

Lots of severe and hazardous weather has been occurring or will occur for millions of people over the next 48 hours.NOAA

After our blustery and chilly Wednesday, clouds will increase Thursday. I expect the clouds to thicken after what could be a beautiful sunrise.

Temperatures will reach into the lower 40s by late in the day, certainly too warm for any wintry precipitation. This will be generally the case during the entire storm for Greater Boston.

Temperatures are predicted to be too warm for wintry precipitation in much of southern New England Friday.WeatherBELL

In the colder air to the north and west, roughly outside of Route 495, the probability of seeing over 4 inches of snow by Saturday begins to increase.

Since the storm system will undergo several changes, the area of moderate to heavy snow could shift a little farther north or even east over the next day.

There is a very high probability of at least 4 inches of snow in the higher elevations and away from the coastline with the upcoming storm.NOAA

In general, rainfall will overspread Greater Boston by sunrise Friday and become steady and heavy. In terms of total precipitation, either snow or rain, I’m expecting an inch to an inch and a half with a few places seeing even more moisture.

By Friday evening most areas will have receive near or over an inch of rain or liquid equivalent from the upcoming storm.WeatherBell

The loop below gives an indication of how the precipitation will move through the region. Notice the rain/snow line over Central and Western Massachusetts moving into Northern New England over time.

If the storm were to take a little more of an eastern track or redevelop off the coast, that rain/snow line could begin to move eastward for the second half of the storm.

Rain overspreads the area early Friday, but falls as snow well inland and to the north.WeatherBell

Winter storm watches have been posted for much of Vermont and New Hampshire and the Berkshires of Massachusetts. These watches are likely to be modified over the next 24 hours and eventually I expect warnings to replace them.

Winter storm watches are up for northern New England and are likely to be expanded.NOAA

There’s even a chance, although not highly likely, that areas west of Boston see a little bit of snow accumulation as the storm comes to an end Friday night and early Saturday. This will depend on if the cold air returns in enough time before the precipitation shuts down. I do expect Saturday and Sunday to be dry and seasonably chilly in the wake of the upcoming storm. It will be blustery behind the storm especially on Cape Cod and along the Maine coast.

Low pressure heads in to the Gulf of Maine Saturday leaving clearing, blustery conditions in it’s wake.Tropical Tidbits