This is a challenging storm. If this was a typical January storm, this would be a monster snow storm ... but it is too warm. Also, if it were even warmer it would be a heavy rainstorm. But some cold air will be created and drawn in by this storm leading to a potpourri of precipitation types. If I were to guess it might break down like this: 60% rain, 30% sleet, 10% wet snow.
The maps below provide the visuals of how tough this call is. Also, a very small change here or there may cause a significant change in the forecast.
This map illustrates the challenge with this storm. This map shows the type of precipitation that the model is predicting. The yellow is a mix of rain/snow and sleet. To see a large area like this means that a temperature change of 1 or 2 degrees in the lower 5000' of the atmosphere will be the difference between rain, sleet and snow. The map above shows what is expected Monday evening at 7 pm.
This map shows what to expect at 1 am Tuesday. This shows and expanding area of snow with again a large area of mix. The low center is still well south, due east of the VA Capes.
This map is valid Tuesday morning. It shows the storm winding down for our area and areas to our S and W. There is still lots of snow and mix in NY and central/northern New England.
This map shows the amount of precipitation that could fall as sleet. This shows for our area about .3 - .5 inches are sleet (that is when melted down). This would be near 1" of sleet. This would create a mess. How about snow?
This is the model expectation for snow. This shows for our area about .1 - .2 would be snow (melted). This would amount to about 1" because it would be wet snow.
So the conclusion is this:
1) Storm emerges off the VA Capes, and becomes a slow moving Nor'easter as it moves N-NE then NE by Tuesday afternoon.
2) Heavy rain will develop Monday morning and then mix/change to sleet as atmosphere cools. The heavy precipitation is key to cooling the atmosphere. If it does not become heavy then it will stay rain. If it stays heavy for longer than I think, it will change to sleet/wet snow.
3) Rain/Sleet may mix/change for wet snow at times overnight. This is highly dependent on steadiness of precipitation. If too light and spotty it will not change to snow.
4) Rain/wet snow ends Tuesday morning.
5) Strong gusty winds. Damaging along the coasts, not so much here, but with wet ground a power outage may be possible even here.
6) Heavy rain could cause some minor poor drainage flooding on Monday before any changeover.
7) Temperatures fall Monday from the mid 40s to the mid 30 by evening.
This is a big storm. Lots of wind. Lots of precipitation. Take it easy.
Pastor Terry. He received his bachelors degree in Meteorology from the State University of New York at Oneonta, in 1994. The education continued as a hobby by reading the blogs of some of the best forecasters in the business. Although forceasting the weather is an imperfect science, it is a pleasure to follow what the Creator has made.