March so far started cold, moderated and then a major snowstorm hit a good portion of Upper Michigan.  Last year, a snowstorm hit early in the month, but that’s where the similarity stops.  March 2012 brought historic warmth to the U.P. and a good share of the eastern U.S. (Image 1 above).  The weather over the U.S. was dominated by a huge ridge that covered much of eastern North America.  It helped pump up warmth that never really quit.

This year, the pattern configuration is much different.  Here’s a case in point:  on March 11, 2012, a record high of 63 was set at the National Weather Service (NWS) near Negaunee. This year, a record 14.4 inches of snow fell on the 11th at the NWS. Last year, the pattern was dominated by that building ridge (Image 2).  This year, a deep trough was forming right where the ridge was strongest last year (Image 3).   Last year the ridge kept building, reaching a high mark about St. Patty’s Day.  That day, the high reached a record-shattering 75 degrees.  The next three days it was 78 and on March 20, 2012, a historic high of 81 degrees was observed.

I’m not predicting a record cold March 2013, but it does look like the cold will hold for a good share of the month.  Here’s a 15-day forecast valid on March 26 (Image 4).  It shows essentially the same pattern that’s been dominating the last couple of weeks; a deep, cold trough nearby with high latitude blocking.  To say spring will be delayed a bit is an understatement—especially compared to last year.