The past 5 days (Tuesday 1/22 – Saturday 1/26) have been quite impressive in the Mid-Atlantic region with respect to the cold wave that has gripped the area.  In Philadelphia, for example, the average temperature in this 5-day stretch was 12.4 degrees below normal and it was the longest stretch of sub-30 degree days (5) since January 2004.  In DC, the average temperature was 11.2 degrees below normal in the Tuesday to Saturday time period, and it was the longest stretch there with sub-freezing temperatures (4 days) since February 2007.  Also, the DC region experienced two snow events in this 5-day stretch and, while they were small accumulation events (an inch or two), there was virtually no snow beforehand in the entire preceding part of winter.  New York City joined in on the cold as well with average temperatures 13.6 degrees below normal between the 22^nd and 26^th of January.   Much improvement in temperatures is in store for this region by mid-week, but then it turns colder again by the time we begin the new month.