This storm will drop a rain/snow mix south of the 1 inch line, with a slushy coating possible across northern MD into Philadelphia. Higher elevations will do better with this event, especially from southern PA southward.
A rather weak disturbance will slide across the region tonight into tomorrow, bringing wintry precipitation to the region from DC northward. South of DC will be mostly (or all) rain, with a rogue snowflake or two possibly mixing in with the rain, especially if the precipitation rates are high. Temperatures are cool enough aloft for snow, but the low-level temperatures are forecast to be above freezing up through southern PA, which will keep accumulations limited on the southern edges. If low-level temperatures hold warmer than expected, snow totals will be lower than forecast.