http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2058

A spring heat wave like no other in U.S. and Canadian history
peaked in intensity yesterday, during its tenth day. Since record keeping began
in the late 1800s, there have never been so many temperature records broken for
spring warmth in a one-week period--and the margins by which some of the records
were broken yesterday were truly astonishing. Wunderground's weather historian,
Christopher C. Burt, commented to me yesterday, "it's almost like science
fiction at this point."

http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2059

Breaking all-time April records for warmth in March Not only did
many locations in Canada set records for their all-time warmest March day during
"Summer in March, 2012", a number also broke their record for warmest April day: