9:30 PM UPDATE
Snow has started to fall on Long Island, New York. Within the next few hours, it will arc northeastward into Connecticut, right within the time frame we have been anticipating the start to the precipitation. There is still some uncertainty about the northern extent of the cold air; the latest run is slightly colder, offering more snow. Also, the final push of precipitation at the tail end of the storm may bring a quick snow burst. The NWS notes vigorous vertical velocities as the mix changes to snow between 7 and 11 AM; this feature might push out a quick inch or two, especially along and north of Route 6.
A large part of the state may have a snowy Christmas. A winter weather advisory is in effect late tonight and tomorrow morning.
SNOW AND ICE ARRIVE TONIGHT
Just in time to give Santa an easy runway on the roof, snow and a mix of sleet and rain will begin to develop across the state. For most of the state, the precipitation will start as snow. For areas right along and south of I-95, warmer air may hinder snowflakes, promoting a wintry mix, instead. Snow or a mix will begin as early as 10 PM in southwestern Connecticut, and envelope the whole state by 1 AM. The northward movement of the line where snow will mix with sleet and rain will start to occur almost immediately, changing the snow to a mix in southeastern Connecticut in the 2 AM time frame, and up into Greater Hartford between 2 and 4 AM. All the while, temperatures will be in the upper 20s and low 30s in much of the state, but slightly milder in southeastern Connecticut, with readings in the middle and upper 30s.
A SNOWY, ICY MIX CHRISTMAS DAY
The storm will continue Christmas morning. The mix line, mentioned in the discussion for last night, may make it past Hartford to eastern Litchfield County for an hour or two in the very early morning, but then retreat back south through the state from 5 until 8 AM, as colder air flows into the region from the northwest. There could be a few hours of light snow before it tapers off.
The amount of time that the mixing to ice and rain occurs will have a huge impact on accumulation totals. As it looks now, areas north and west of Hartford will likely receive 2-5” of snow. In areas along I-84: Danbury to Waterbury to Hartford to Manchester and into northeastern Connecticut, there will likely be a slushy coating to two inches. And along the shoreline and in areas southeast of Colchester, there may be very little accumulation at all.
The last steady snow will taper off by around noon, and soon after, the clouds will give way to some sunshine.
Because the storm will be swift, Christmas afternoon will be partly sunny, windy and cold with highs in the low to middle 30s. Gusts could reach to over 30 MPH.
BITTERLY COLD THE REMAINDER OF THE WEEK
Colder weather will be here mid-week, so any snow that accumulates on Christmas will be present for all who choose to try out the new sleds the received for Christmas. An Arctic high pressure cell will meander into the region over the next several days, offering the cold, but fair, weather. Tuesday should be partly sunny and breezy with lows teens and highs in the 20s. Tuesday will be partly sunny, with only the slightest chance of a flurry. Wednesday, Thursday, and Friday will be dry and cold with partly sunny skies as highs struggle to reach into the upper-teens and 20s. A brisk northwesterly breeze will add to the chill. Lows at night will be in the single digits. If the wind goes calm, some towns will have lows below zero.
SNOW POSSIBLE FRIDAY
Another chance for snow may come Friday. As it appears now, the storm causing this chance will be far out to sea – past the “40-70 Benchmark” that tends to be the sweet spot for southern New England storms. But, there will likely be a trough extending into New England from the storm center, that will bring a period of light snow. Once the system leaves, a cold northerly wind will maintain the Arctic chill that we will have had in place for most of the week prior.
COLD AND QUIET NEXT WEEKEND
Both Saturday and New Year’s Eve Sunday will be cold and fair, with highs in the 20s and lows in the single digits and teens. Arctic High pressure, straight from Canada, will be the cause of the continued cold regime.
Meteorologists Mike Cameron
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