May has been frigid slowing the planting and emergence of the summer crops in the southern prairies of central Canada. Late freezes and even snows occurred in central Canada through the entire month right up to the last day.
The chart above shows the May 2009 temperature anomaly through May 28th. Parts of central Canada (areas near Churchill, Manitoba) are running as much as 13 degrees F below normal for the month through the 28th. Every day this month has seen lows below freezing in Churchill and only 3 out of the first 30 days had highs edge above freezing. June will start cold.
Hudson Bay remains mostly frozen though most of the seasonal melting occurs in June and July most years. Parts of the south central region were also cold in April averaging 3-5 F below normal. The winter (December to March) was a cold one for southwest and central Canada but warmer in the far northeast.
The global data bases have large gaps in Canada, Africa, South America. So they will not reflect this in their global May anomalies as well as the satellites that see the entire surface - land and ocean excluding high latitude polar. UAH satellite derived lower tropospheric anomaly was just 0.09C compared to the GISS 0.66. Part of that is the GISS use of the coldest 1951-1980 base period while satellite data was limited to post 1979.
Meanwhile the arctic ice remains higher this data for any year this decade in a virtual tie with 2003.
Given the polar stratospheric aerosols from Mt Redoubt, and a colder Atlantic and a continued cold Pacific, the recovery from the minimum of 2007 should continue this season.