1/20 DC/VA/MD Weather Outlook and Snow ALERT

I will watch for changes, but it is looking pretty certain that a significant but not historic system will affect the region.

Bottom line, the system that will come through does not appear to phase with other systems which had been important for a serious amount of precipitation. Without this phasing the amounts will be decent, but not historic.

Taking models right now (Obviously forecast will be adjusted if needed)

An area north of and including Roanoke to Richmond to Waldorf will likely see 4-8 inches with some bigger spots approaching 12 inches. Reason for some higher amounts in some areas will be the possibility of  convective banding of snow or even thundersnow! There will be mixing concerns along the coast and southern regions after an initial period of snow.  

Concerns:

1. Phasing could come back into play, which would likely re-appear today. If so, mixing would get involved in more areas and higher amounts where snow was the primary precip type.
2. A coastal system will take over at some point. Though this could increase snow amounts, I have seen these systems become, what I like to call, Piedmont Robbers! The energy during transfer takes the heavy snow band and jumps the piedmont areas.
3. The Coastal system MAY be close enough for a backlash snow which could greatly increase amounts somewhere (Maybe east of I-95!)

All for now!

Remember, Mid Atlantic Weather Forecasts ae not OFFICIAL forecasts and should never be used to make life saving or property saving decisions. Please cnsult with official government forecast offices or other weather outlets for these decisions!