The 18z GFS this evening had a slightly weaker low in the SW that stayed separate from the western trough. High pressure in the southeast still forced the low northward into the Great Lakes region, however as a weaker low that transfered energy south and east earlier than before. This allowed colder air to remain in the region longer. This is ONE model run and also is an 18z run (statistically worse than the others because of a lack of new data). While it was a nice sight for sore eyes to have a trend the other way, Im waiting until the 00z run to start thinking about the GFS turning around. I've expected the models to trend back south towards the time of the event, so this may be it. At this point NWS has all rain on Monday, but I have kept ice in my forecast for Keene. Consensus on QPF is at least 1.0" across New England. Using GFS temperature foreacast, Keene would get 1 to 2 inches Sunday followed by a period of ice, then rain on Monday and a brief period of snow Monday night. Im still convinced that a track about 100 to 200 miles east of the GFS is more likely, which would allow temperatures about 5 degrees cooler. This would result in up to 6 inches of snow. A track further east would be even more. At this point, still watching the models. We have 5 days of flip flopping to do, so do not get hung up on one model or one run. It should be noted that the surface low tracking further east would not prevent an ice instead of snow situation. It is necessary for the 850mb low to track just to the east of the area as well to ensure a BL that is totally below freezing.
P.S. (6:45pm)
GFS Ensembles have also come out further south and east. On my count, 7 of 12 have 850mb 0C south of Keene on Monday.
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