Here is a breakdown by metro region in the Mid-Atlantic’s I-95 corridor as to what to expect during this long duration major winter storm:
DC metro region:
Snow will continue through the day in the DC metro region during the “overrunning” phase of the event with up to 5 or 6 inches possible by day’s end. In fact, phase 1 could turn out to be the time period with the “best” accumulating snows in the DC metro region although I do expect some additional accumulations from “wrap around” snow associated with the coastal storm (i.e., during phase 2). The snow will tend to lighten up by early tonight and the precipitation will also become mixed with ice and/or rain and it should continue in a spotty fashion into Monday morning. Any mixed precipitation will then likely change back to all snow later in the day on Monday as colder air wraps around from the north/northeast and it should continue as snow or snow showers into Tuesday with some additional accumulations likely.
Total snowfall estimates for the DC metro region: 6-12 inches.
A “Philly special” and a NYC classic:
This could turn out to be one of the all-time classic snowstorms in the northern Mid-Atlantic region extending from south-central PA to eastern PA to upstate New Jersey to southeastern New York and this includes the Philly and NYC metro regions. There can be a snow shower or two this morning in the Philly metro region, but the steadier snow will arrive during the mid-day or early afternoon hours and then it arrives by early evening in the NYC metro region. The snow will continue tonight and it could mix with sleet at times; especially, to the south and east of Route I-95. Any mixed precipitation tomorrow night should change back to all snow later in the day as colder air wraps around the intensifying storm off the Mid-Atlantic coastline. The snow will become heavy at times from later tomorrow into Tuesday with significant accumulations. Given very strong dynamics in the upper atmosphere, there is the potential for “mesoscale” or small-scale banding during the height of this storm containing brief outbursts of heavy snow and possible thunder. In addition, the winds will increase markedly later Monday resulting in some blowing and drifting of the snow and those strong winds will actually continue right into mid-week.
Total snowfall estimates in the Philly and NYC metro regions: 12-18 inches and there can be isolated higher amounts.
Stay tuned for further updates as this is a complex storm system.
Meteorologist Paul Dorian