Major winter storm becoming more likely---Model Analysis---

The model guidence are slowly closing in on a solution. The GFS is stay relatively in place, while the Euro is actually the one making the shifts. Perhaps the GFS had the right idea all along. With the GFS solution, the focus of heavy snow would be to our south and east as the low tracks just outside the benchmark. It should be noted that the GFS has shifted ever so slightly northward, and due to its usual southeast bias, we can probably expect another 50 miles or so by Monday. My confidence in accumulations over 4 inches is now high for Keene, as even the eastern most outliers are close enough to the region to deliver some north west edge precipitation. As for SE MA, accumulations based on the GFS would exceed 3 feet! This solution is a bit extreme especially with the amount of strengthening the low does off shore. The Euro, despite 50 mile shift eastward since yesterday, continues to track the low over Cape Cod. While this solution would give parts of SE New England a mix of rain and snow, it would mean heavy accumulations likely inland over SW NH and NW MA. My confidence in accumulations over 8 inches is medium.



Taken at face value the GFS still gives SW a storm to remember, and meanwhile hits the cape and islands with over 3 feet of snow. The 06z run of the GFS (the latest) still gives the Cape a nice 2 to 3 feet, but also introduces a sharper cutoff and only 6 to 10 inches or so. The 06z run also shows a slightly weaker low and a track maybe 40 miles further south. It is important to remember though, that statistically, the 00z runs are the best, and that the 06z and the 18z are the worst runs. This is why you might here jokes like "the 18z run of the GFS shows a storm 384hrs."





Getting to the NWS issued products, a special weather statement in effect for all of SNE has been issued this morning. In addition, the AFD continues to use enhanced wording. Winter storm watches have now been issued for eastern Nebraska, western Wisconsin, eastern Wisconsin, central Illinois, most of Indiana, (and have recently been expanded to include) southern Ohio, eastern Ohio, western Pennsylvania, northern West Virginia, northern Virginia, and most of Maryland.

Winter Storm Watch

The NWS has also elevated POPs for Keene to 70% (likely) both Tuesday Night and Wednesday with 50% (chance) POPs Wednesday Night. And added "light accumulations possible" for Tuesday Night and "moderate accumulations possible" for Wednesday.

My next snowfall forecast will be issued in the winter weather outlook page around noonish.
Please stay tuned for further updates on this potential winter storm.

Postscript:
Most medium to long term forecasting models are also indicating a significant blast of cold behind this storm. However my thought is that it will be short lived. Temperatures will be held down to around 20 for highs and zero for lows through Friday but moderation will begin by the weekend, and may be the start of a trend toward average to above average temperatures for the last week of February.