Update, 9 p.m. Monday
If you are new to my blog, I like to periodically update the days entry as conditions change. Presently not much is different from this morning. I don’t see a trend of more snow. As a matter of fact, the transition from snow to mixed precipitation may occur faster Tuesday morning.
I am adding a map of potential glazing below. The areas in pink could see some icing between the snow and the eventual change to rain at the end of the day. There’s a small chance there may be a few pockets with enough ice accretion for some power trouble, but this is not going to be a widespread icing event.
Reiterating, the biggest impact of this small event is because of the timing during the morning commute. If you don’t need to drive from about 5 a.m. until 9 a.m., you’ll save yourself a big headache.
In terms of snow events and accumulation, this isn’t very significant. However, since it’s the first one, the attention this garners is higher than a typical coating-to-three-inch snowfall.
There is a winter weather advisory for much of the area. These are put up for small snow, sleet, or freezing rain events, and it’s another indication this isn’t going to turn into a big storm. This is the same system that has brought everything from blizzard conditions to tornadoes to other parts of the country.
Colder air has worked into the area overnight and has set the stage for precipitation to fall in the form of snow for a few hours Tuesday morning. The heaviest snowfall will be north of the Mass. Pike and west of Route 495.
In the city of Boston a slushy accumulation of up to and inch and a half is possible. The roads and the ground are still relatively warm, so there will be some melting from the bottom up as soon as the snow lightens up and eventually becomes mixed with and changes to rain.
There are two maps below for snowfall prediction. The first is my map and the second is a map of model consensus. The models put out exact numbers, but it’s rare they are that accurate, which is why we all use ranges.
I’ll update these numbers here an on Twitter if things change later today.
There will be anywhere from half an inch to an inch of total precipitation with this storm, so if it was cold enough, we could have gotten a sizable storm. The warm air will keep most of the event liquid, not solid.
You won’t need to put down sand or salt in the city with this event as it’s just going to get washed away quickly during the morning. Temperatures will be going up, not down, so ice isn’t an issue. Where plowing might occur is where snow amounts end up over two inches. The areas north of Route 2 and west of Route 495 have the best chance of icy roads as temperatures fall slightly below freezing Tuesday night.
Timing of the snow
The snow arrives after midnight and falls during the morning commute Tuesday. In spite of no school tomorrow, traffic will still likely be slow because of precipitation and secondary roads over inland areas will be slick. As you get closer to Boston expect nothing but wet pavement.
The rain ends Tuesday evening and then skies partially clear for Wednesday. Another weather system brings rain overnight Wednesday night, but no snow.
First Night and New Year’s Day
Tranquil and milder than average temperatures take us out of 2015 and into the New Year. Highs on Thursday will reach well into the 40s, and some areas could again touch 50 degrees. Boston has done that 20 times this month, the most ever recorded.
If you are planning on being outside New Year’s Eve, the good news is it won’t be very cold. During the evening temperatures will hover in the upper-30s to near 40 and fall to the mid-30s by midnight.
The upcoming weekend appears dry and seasonably cold for early January. Temperatures may actually average slightly below normal. I don’t see any major prolonged cold or significant snow in the 10-day forecast.