BEST did a new release today (July 29, 2012). As I’ve been doing with other data sets, I am graphing all the monthly anomalies and calculating the 5 year mean backwards from the most recent month (November 2011 for BEST).
BEST says the most recent 5 year period TMAX in the USA is .5C colder than the previous 5 year period and colder than the 10 period starting around 1933 and extending into the early 1940s. And also colder than the mid 1950s and around 1990.
Even more interesting, the most current 5 year period is only .57C warmer than the earliest 5 year period in the 1840s.
5 year means in blue boxes on the graph. The value is the departure from the Jan 1951-Dec 1980 average. Data here.
(And thanks to Anthony , this BEST data may be exaggerating the small amount of warming they found).