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Some very good meteorologists are arguing with each other on some online weather bulletin boards about what is about to happen in January. What is fairly well agreed upon is that high pressure in the North Atlantic is gradually building westward toward Greenland. When high pressure sets up shop there, it is called a Greenland block, and that tends to cause the jet stream to buckle southward behind it into the eastern U.S., allowing colder air to move farther south and storm systems to dive farther south. This is called the negative phase of the North Atlantic Oscillation, from which we get a majority of our significant winter storms. The problem is that the pattern over the Pacific isn't lining up in concert, with low pressure in the northern Pacific threatening to continue blasting a mild jet stream far to the north across the U.S. So there is a lot of confusion and dissent over what is about to happen as these weather features interact with each other.

Suffice it to say, though, that there appears to be at least a window for colder weather and possible winter precipitation during the first week of the new year. Whether that pattern sets up for a while, or breaks down quickly, remains questionable at this time.

Some forecast models have been showing moisture and cold air intersecting near us around the Jan. 2-3 time frame. While there is some potential for a winter storm around that date, the odds are still better that it would be more of a north-tracking storm that could bring sleet/ice/rain rather than a south-tracking storm for primarily snow.

All of this is subject to change. The next few weeks could be very interesting, though, as different major weather factors interact for what could a variable forecast. I'm thinking we're still a few weeks away from the peak of our winter locally. It may take some time for the proper pattern to build in.