Arctic Air On The Move
High pressure parked over the Ohio Valley is steering in cold dry weather from Canada. Plenty of Sunshine today with highs in the Upper 20′s and Lwr 30′s. An Arctic front pushes through tonight and the real cold air gets on the move. Arctic air will settle in after midnight with clear skies and calm winds. Lows will drop below zero in interior valleys while hover near 10 degrees at the coast.
A frigid start Monday will only moderate slightly by afternoon with highs only able to climb into the teens and Lwr 20′s with sunny skies. Canadian air with low sun angle reflecting off the snow is not the best ingredients for a warm up.
But a shift in the wind can make a dramatic difference! As the high pulls off the coast, winds will start to shift to the ESE wind direction. This will start to bring warmer air in off the water by Tuesday… Just in time for our next storm system!
A trough in place up the eastern seaboard will steer in warming SW winds aloft and direct moisture up the coast towards New England. Warm air will over ride the cold air down at the ground. It is a perfect set up for a wintry mix to form. We will likely see quick burst of snow in southern New England during Tuesday morning with plenty of cold air around in the low levels of the atmosphere. As easterly winds shift in…these will provide a warming influence to the boundary layer ad allow a change over to rain at the coast as early as 11 AM.
The cold will hold on longer in the valleys and NW hills. There is the potential for a few inches of snow before a transition to sleet and freezing rain by the midday and afternoon. These icy conditions could last for a few hours before the warmth takes over in all levels and we change over completely to rain in all areas by night.
Winter weather advisories may be needed in places like the Berkshires and Monadnocks, who may see 3-4″ of snow, then Ice before a change to rain. Worcester Hills will likely see 1-3 before a change to ice then rain. Northern New England will hold on to the cold the longest and has the best chance of seeing the most snow…especially Vermont and New Hampshire… Snow will be changing to an icy mix here and could make for some pretty treacherous driving Tuesday afternoon and night….but even here a change over to rain at night as mild air will pump temps to near 40 degrees by night.
Lingering showers with areas of dense fog Wednesday morning with drier weather moving in by afternoon. Very Mild to start with falling temps late in the day as cooler dry weather will move back in to end the week…but there are questions the farther out you look.
Friday’s storm appears up for grabs right now. The GFS has a storm Friday, while the Canadian and Euro slow everything down and have a first wave missing south and a stronger more organized low gathering steam and heading up the coast from Sunday. Favoring this for now…Very low confidence on how this will all shake out this far out…Whenever that storm finally does push through, much colder air will follow in behind it to drop our temps into the teens.
So Needless to say we are tracking two storms…both will have considerable moisture and Ptype issues to deal with. As the NAO becomes less negative, and the blocking pattern begins breaking down…these ptype issue storms are becoming frequent as warmer air can be drawn in. This could be the case for the next few storms…until the next time the NAO decides to go back in the tank….in February? This could be one of those winters which last well into spring. Unlike last winter which was mostly over by February. This one looks like it has plenty of more life to it.