Significant Winter Storm Likely Tuesday-Thursday

Synopsis:

Once again, north of the dashed line is where we expect precip to remain frozen and/or freezing during the entire storm duration.

We kept our scenario map pretty general, anyone in the wintry mix should generally expect to see pretty much every wintry precip type at one point or another. The big question with regards to ice is going to be how much cold air aloft holds and how much of a secondary low forms. If the cold holds more aloft, expect more sleet than zr. The reason winter storm watches are issued attm (esp in Mount Holly, and State College regions) is to highlight areas under the threat for severe icing, so folks in the watches right now stand the best chance for seeing alot of freezing rain.

Most of our T-3 inch range on the snowfall map across PA/NJ is going to be accounting for the possible front end snow/sleet associated with this system. Further north across Upstate NY/New England, thermal profiles are more favorable for a prolonged period of snow...mixed with sleet...to be the dominant form(s) of precipitation lasting for most if not all the event, especially across areas to the north of I-90. During the day on Wednesday, warmer air aloft will move into western/central/southern New York leading to a changeover to mainly sleet/FzRa which will bring an end to the accumulationg snowfall across areas south of I-90. Total snow amounts here should remain under warning criteria with a general 2-5" expected. The exception to this region will be the central/eastern Catskills where snow...mixed with sleet will persist for longer period of time before a changeover/mix to Sleet/FzRa occurs. Here, low end warning amounts of 5-8" are expected.

For areas north of I-90/east of I-81, this storm will bring mainly snow...possibly mixed with some sleet (especially across Mohawk Valley/Hudson River Valleys). A general 6-10" is expected across the Adirondacks/Greens/Berkshires/Whites/Monadnocks, with slightly lower amounts of 5-8" for the Mohawk Valley/Hudson River Valley.

As the coastal Low takes over, and moves northeast into the Gulf of Maine on Thursday, moderate-heavy snow will be on-going into most of Maine, with the possible exception across the immediate coastal counties where enough warm air will result in mixing and even a possible changeover to plainrain not out of the question. Therefore, lower amounts have been forecasted for the coastline. Further inland, mainly snow... possible mixing with sleet at times will produce snowfall totals of 6-10" overall, with some of isolated higher amounts possible.

Final adjustments likely after the 0z runs.

...MAG/LTE