The temperature reached 50 degrees in Boston yesterday, the first time we were warmer than 40 degrees since last Tuesday. Weather does have rhythm and that was the second Tuesday in a row we watched snow melt in southern New England.
It was a warm front pushing to the north that generated yesterday's warmth, and more snow in northern Maine. Now a new cold front coming in from the north generates a few snow showers a return to more seasonable chill today.
We should be mostly sunny away from the mountains with temperatures holding in the 30s, except falling into the 20s in far northern New England. Wind from the northwest 15-20 mph. Snow showers in the northern mountains may add up a couple more inches.
Cold high pressure from Canada is overhead tomorrow with sunshine and temperatures starting off in the single numbers and teens, rising to the 20s and low 30s.
High pressure goes offshore on Friday with a return flow from the ocean. Clouds will return with snow developing for most by lunch time.
Along the south coast any precipitation should be light and quickly change to rain. But from the Massachusetts Turnpike and points north we may get a couple of inches of snow by afternoon.
Snow may let up Friday night leaving us with icy spots and fog early Saturday.
A more powerful system likely brings a period of wintry precipitation most of Saturday, with snow changing to rain in most locations.
However, once again in Maine, and perhaps eastern New Hampshire, we may have rain falling with temperatures in the 20s.
This may set the stage for significant freezing rain event Saturday afternoon into the evening.
Otherwise we will have rain showers and dense fog with temperatures rising into the 50s in southern New England.
Precipitation shuts off Saturday night for a little bit of a lull possible Christmas Eve day Sunday, leaving us mostly cloudy with some light rain or snow returning.
Colder air is working on Sunday so any rain will be changing to snow for most by evening and overnight. Sunday night looks wintry with snow, perhaps becoming heavy at times away from the shore, and snow or rain near the coast.
Christmas morning may start off with snow, with snow or rain at the shore ending as snow, then breaks of sunshine before sunset.
Temperatures on Christmas will be falling from the 30s into the 20s.
It's too early to give accumulations, but the combined events from Friday through Monday will likely create difficult transportation issues.
Still a lot of time to fine tune this extended forecast.