and with it comes a drastic sharpening of the north to south temperature gradient across the United States and a baraclinic area stretching from the Ohio Valley to the northeast early this week. With this comes a significant weather system that start as a disorganized storm in the Midwest early this week but with a big injection of moisture from the Atlantic will evolve into a major precipitation producer across much of New England. This is a very different type of storm than what we have seen this year and much more typical of a storm one might expect in a strong La Nina year such as this one. As mentioned a few days ago, the region will have to survive a tremendous push of mid-level warmth. Temperature cross sections reveal that it might be a tough go, for a time as precipitation is likely to start as a sleet or freezing rain mixture. As the storm over the Atlantic coast continues to push northeast, move over the cape and deepen, precipitation will become heavier and consequently we should see just enough cooling at these critical layers of the atmosphere to see freezing rain and sleet change to snow. It is so close right now it really could go either way, the level of warmth at these middle layers is a few thousand feet thick and temperatures in this layer will only be about 34 so just a slight shift in this progression and we could be all snow.
Precipitation should begin as snow in the midday hours Tuesday and this icy mix, if it does occur will take place in the evening or overnight hours and then we should see another additional period of snow Wednesday morning before everything tapers off. I am going to say about 6-10 inches of snow sleet and some freezing rain right now. My computer is about to run out of batteries so I will expand on the post later to discuss another possible storm later in the week and what still appears to be a favorable pattern lasting into next week.