January 21, 2013: Potential Winter Storm Coming This Friday

Professor Storm will be back full-time in the classroom next week...but in the meantime, he may be offering up a "multiple-choice" winter day this Friday - that is, a wintry mix of snow, sleet and freezing rain. 

We are still several days away from the event, but the ingredients will come together, including (1) the remnants of an arctic air mass;  (2) relatively warm, moist air off the Atlantic sliding in overhead, and (3) an area of low pressure to pull it all together.   When this vertical, layer-cake type of temperature structure develops east of the Blue Ridge Mountains in Jan-Feb, it often spells a wintry mix.

Below is the medium-range surface forecast map, for Friday morning, showing the storm approaching from the Ohio Valley, with cold air lingering over the Mid Atlantic.  Note that this is NOT a coastal low or Nor'easter type of system, one that is not expected to become very intense, and also a fast mover - so I don't expect prodigious amounts of wintry mix.  But there may be enough to create some local hazards, and prove to be an overall forecast headache:

NOAA

 Stay tuned right here as I update this blog daily through the week.