What had been forecast to be a moderate winter storm for Chelmsford and the Merrimack Valley is beginning to pickup momentum and could wind up packing a pretty good wallop.
The latest forecast from the National Weather Service is now calling for Chelmsford and the surrounding area to get 3-7 inches of snow.
Snow is expected to continue through the night and a Winter Storm Warning remains in effect until Sunday at 7 a.m.
Visibility on the roads is limited and fog is expected to roll in around midnight to 2 a.m. making it worse. The low temperature tonight will be around 25 degrees. There will also be steady north winds overnight around 11 mph.
The snow may initially be mixed with rain near the coast, according to the National Weather Service, before changing to all snow. The heaviest snow should fall throughout midnight, with snowfall rates of 1 to 2 inches per hour expected.
Measured snow totals from across the region are available on the National Weather Service's website.