The first measurable snowfall of the season for the metropolitan regions of New England is now in the forecast.
You won't believe where the snowstorm is originating: on the United States border with Mexico, in the Rio Grande Valley of Texas, where snowfall rates of 1 inch per hour are occurring. A winter storm warning is in effect all the way south to Corpus Christi, Texas.
This weather system is along the same powerful front that passed through New England with the wind and rain Tuesday night. That front has stalled offshore and we have one low-pressure system after another riding along the front stalled from Georgia to south of New England.
The wave moving off Texas into the Gulf of Mexico will bring snow to Louisiana, Mississippi, Alabama, Georgia and then up the eastern seaboard over the next two days.
Snow arrives in New England at the south coast on Saturday morning, where it'll be warm enough that it's mostly rain on Cape Cod and along the immediate shoreline.
The snow will advance northward into the Merrimack Valley by late afternoon, and then into northern New England during the evening.
Snowfall should not be that intense, with rates of about 1/4 of an inch or less per hour. But eight hours at that rate gives 2 to 4 inches of snow through the duration.
Because much of the snow is falling during the day and temperatures are marginally cold, snow should accumulate more on non-paved surfaces, though higher elevations and on the north side of hills we may have to do some minor plowing of the snow.
Steady snow ends from west to east Saturday night into early Sunday, followed by partial clearing. Snow showers and cold wind may persist right through Sunday and Monday.
After that we may see more organized snowstorm with more in the way of wind arriving on Tuesday, with very cold air and wind coming in Wednesday.