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Hi everyone! Thanks for visiting!

It’s time for a look at the week ahead, highlighted by an extremely cold start to the week and a midweek storm threat. The weather this week will be determined by the interaction, or lack of interaction, of a split jet stream (a northern one over southern Canada and the northern US, and a southern one over the central and southern US).

It’s been a cold & dry weekend across the region, and it’s about to get even colder. An Arctic cold front has been moving southeastward across New England today and will push south of the area tonight. This has opened the door for some slightly modified arctic air to move into the area. Boston may fall below zero tonight for the first time since 2005. I’m forecasting a -1F low temperature tonight. Most of the areas outside the city and away from the immediate coast will see low temperatures of -2 to -10. A few isolated colder readings are possible in valley areas where winds could be a little lighter. Winds will be strong enough from the northwest, gusting around 25 mph at times, to produce wind chills of lower than -20 at times tonight into Monday! Under bright sunshine, temperatures will barely recover back to near 10 in most locations.

By Monday night, clouds will be moving in ahead of a weak weather system approaching from the west. This, along with the fact the core of the coldest air will be exiting, will mean that we will not see a repeat of the extreme cold of tonight. Low temperatures in most areas should remain slightly above zero, still very cold certainly, since we will already be nearly at those levels by the end of the day Monday.

On Tuesday, expect clouds to dominate the day. There may be some light snow showers or even a period of light snow as a weak low pressure area with the northern jet stream moves through the region. This is not associated with the potential storm for midweek.

Once this system gets by us, attention will be on the storm threat during the Wednesday-Thursday timeframe. There are alot of factors to consider when forecasting the development and movement of this storm. I have been in great disagreement with the approach taken by many of the media outlets regarding this potential system, and you can see I use the word “potential” for a good reason. We’re talking about computer forecasts of a storm that has yet to develop and is largely going to be made up of energy that JUST entered the northwestern US from the Pacific during the past 12 to 24 hours. Hearing people talking about 1 to 2 feet of snow Wednesday is disturbing to me, because it plants seeds for overreaction of the public, preparing for yet another “storm of the century” as well as anger, if the advertised storm does not deliver. Regardless of how major I think this system has the potential to be, I would never start throwing those kinds of numbers out so far in advance. It’s irresponsible.

That said, I have reason to believe that the impact from this potential storm may range from minimal to moderate, and that we will be spared a direct hit from another monster storm. My favorite and what I feel to be the most reliable computer guidance has been advertising to me that the northern and southern jet streams are going to have a difficult time phasing, or getting together, which is something we usually need to produce a big storm and give it an avenue to come up this way. In this case, I feel that Tuesday’s weaker northern stream system will be well offshore and out of the way, as the southern stream system tries to develop over the southeastern US. There is a boundary forecast to be located off the East Coast on Wednesday. It is my expectation that the new low pressure area developing with the southern jet stream, not being influenced by energy to the north, will tend to develop along this boundary and try to follow it. And since this boundary is not forecast to move a great deal, that will tend to steer the southern stream storm on a more northeastward course, rather than turning it straight north up the coast. A track like this would put southern New England on the northwest flank of the storm, with results being anywhere from a light to borderline moderate snowfall (except mix/rain over far southeastern MA & Cape Cod due to warmer air aloft), or even just a brushing and a lower probability of a complete miss. My leaning at this point is for the first scenario mentioned just above. There is plenty that can go wrong with this forecast, so of course I will be watching and upating as we get closer, as has been needed over and over lately with these storms. For now, I wouldn’t be too worried about getting belted with a massive storm at midweek. And timing-wise, whatever we do get would likely occur mainly Wednesday night.

Later this week, expect a continued cold weather pattern, with the next chance of any storminess coming around Saturday. At this stage, that does not look like a major storm, but could produce quite a bit of wind as it is forecast by most guidance to be a pretty strong northern jet stream system. Looking way ahead, there are signs of another visit from very cold Arctic air behind that system, to end January & start February.