Dec. 1 (UPI) -- The second part of a double-barreled storm is forecast to unload heavy snow and create difficult travel over a large part of the northeastern United States, including some major cities from Sunday to Monday.
A winterlike storm from the Midwest will continue to overspread the region into Sunday night, then hand off to a new coastal storm that strengthens on Monday and Monday night.
Accumulating snow is forecast to occur in Boston, Worcester and Springfield, Mass.; Hartford, Conn.; Binghamton, Syracuse and Albany, N.Y.; Allentown and Scranton, Pa.; and New York City from the storm.
Snow, on the order of 6-12 inches, is forecast from the northeastern corner of Pennsylvania to central Massachusetts and southwestern New Hampshire. However, pockets of 12-18 inches are in store for the Catskills and Berkshires, where an AccuWeather Local StormMax of 24 inches is expected.
Heavy snow is in store for much of the Hudson, Mohawk and Connecticut river valleys with a few inches as far south as parts of the Delaware and Lehigh valleys.
Part of the storm will bring ice, rain and a wintry mix along the Interstate-95 corridor from New York City to Boston Sunday night.
A significant buildup of ice is forecast over parts of southern New England with dangerous black ice travel conditions and the risk of falling tree limbs and power outages.
How damaging the ice storm is from one location to the next will depend on whether the primary form of precipitation is sleet or freezing rain. Sleet tends to bounce off, while freezing rain weighs down trees and power lines.
A glaze of ice, up to 0.25 of an inch thick coated trees and power lines in Garret County, Maryland, on Sunday. Multiple ice-related vehicle accidents occurred in Corning, New York and along I-84 in northeastern Pennsylvania. Most roads were wet in central Pennsylvania, but trees and cars became coated with a glaze of ice.
The middle part of the storm is likely to be the warmest during Sunday night into the first thing Monday. This is when just enough Atlantic Ocean air is likely to sweep in from the south and the east to bring plain rain to coastal areas of the upper mid-Atlantic and southeastern New England.
However farther inland, a wintry mix is in store that includes a substantial amount of ice from east-central Pennsylvania to eastern Massachusetts.
Don't be fooled by mild air during the middle of the storm
Rain showers will change to snow showers over the central Appalachians late Sunday night and Monday as the older part of the storm and its colder air from the Midwest spirals eastward. A coating to an inch or two of snow can accumulate in these areas. However, the rate of snow can increase over parts of central and north-central Pennsylvania due to influence by both the Midwest storm and the coastal storm.
During Monday and Monday night, cold air is likely to collapse toward the mid-Atlantic and southern New England coast to bring a change to accumulating snow.
While an accumulation of a coating to an inch or so is possible around Philadelphia, up to a few inches may fall on the New York City area with several inches likely around Boston. Much heavier snow is likely in the northern and western suburbs of New York City and Boston, with a few inches possible just north of Philadelphia.
So while the Monday morning commute may only bring limited travel problems, conditions may worsen for the drive home Monday afternoon and evening along the I-95 corridor from Philadelphia to New York City and from I-81 from northeast of Harrisburg to Scranton, Pennsylvania, and Binghamton, New York.
Should the storm strengthen a bit more, heavy snow may fall right in New York City and a few inches might occur in Philadelphia during Monday afternoon and evening. Boston could pick up a foot of snow in such a case where rain does not hold back the accumulation.
Some schools that are scheduled to be in session on Monday may have delays or cancellations. Flight delays and cancellations are likely from Boston to New York City and Philadelphia. Ripple-effect days can be felt not only in the Baltimore, Washington, D.C., and Pittsburgh areas, but across much of the nation as crews and aircraft are likely to be displaced as the storm also affected some of the major Midwest hubs this weekend.
Those with flexible travel plans are encouraged to postpone trips due to the risk of black ice and snow accumulation.
Travel conditions are likely to improve dramatically over the region on Tuesday as crews will have been out plowing and/or treating the road with ice-melting compounds. However, snow is likely to start the day in eastern New England.