A mix of rain and snow will begin to overspread the DC Region during the pre-dawn hours on Wednesday. The mix of rain and snow will transition over to heavy, wet, snow from west to east during the morning to early afternoon hours on Wednesday. Secondary, untreated, roads will become snow/slush covered making for slippery travel conditions.
Outer Northwestern suburbs:
- Places like Frederick Maryland and Leesburg Virginia could see snowfall totals of 5 to 7″, mainly on grassy surfaces. ** The highest elevations (those above 2,500 feet) could pick upwards of 8 to 12″ of snow ** The Shenandoah Valley and foothills (below 500 feet) east and west of the Blue Ridge will likely see snowfall accumulation totals between 5 and 7″.
Northern & western Suburbs of DC and Baltimore (Fairfax, McLean, Reston, Gaithersburg, Rockville, Columbia):
- The immediate northern and western suburbs of DC and Baltimore will likely see snowfall totals of 3 to 5″.
- Downtown Washington and Baltimore will lose a lot of potential accumulation due to the relatively warmer waters of the Potomac and Chesapeake Bay as well as the urban heat island effect. Here I think accumulations will run between one and three inches on grassy surfaces.
- Southern Maryland and the Northern Neck of Virginia will be the last to change over to snow and these areas will probably remain just above freezing for a large portion of the storm. In these areas I expect snowfall totals of one to three inches, although if temperatures cool faster than expected, there could be some locations picking up 4″.