Here are two dandy posts about the exceptionally warm weather this month. First, from the National Weather Service in Grand Rapids, Michigan:

000
SXUS73 KGRR 221753 CCA
RERGRR

RECORD EVENT REPORT...CORRECTION TO RECORD HIGH DEPATURE [sic]
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
148 PM EDT THU MAR 22 2012

...ALL TIME RECORD HIGH DEPARTURE FROM NORMAL SET AT GRAND RAPIDS
MI...

WITH A HIGH OF 87 DEGREES YESTERDAY AT GRAND RAPIDS ON THE 21ST AND
WITH THE NORMAL HIGH BEING 47 DEGREES THE DEPARTURE FROM NORMAL WAS
40 DEGREES. THAT BEATS ALL TIME PREVIOUS RECORD OF 38 DEGREES ON
SET ON JANUARY 22 1894.

THE MEAN TEMPERATURE ON THE 21ST WAS 74 DEGREES. THAT WAS THE
HIGHEST DAILY MEAN TEMPERATURE EVERY RECORDED IN MARCH. IT BEAT THE
PREVIOUS RECORD OF 72 SET ON MARCH 29TH IN 1910. THE PREVIOUS
RECORD FOR THE 21ST OF MARCH WAS 62 DEGREES IN 1938.

THAT 74 DEGREE MEAN ALSO RESULTS IN THE ALL TIME RECORD DEPARTURE
FROM NORMAL AT GRAND RAPIDS FOR ANY DAY OF THE YEAR FOR THE ENTIRE
PERIOD OF RECORD. THE MEAN OF 74 DEGREES WAS 37 DEGREES ABOVE
NORMAL. NO OTHER DAY ON RECORD AT GRAND RAPIDS HAS HAD SUCH A LARGE
DEPARTURE FROM NORMAL. THE PREVIOUS RECORD OF 34 DEGREES HAPPENED
TWICE... ONCE ON MARCH 8TH IN THE YEAR 2000 WHEN THE MEAN WAS 67
DEGREES AND THE NORMAL 33...THEN AND ON MARCH 13TH IN 1990 WHEN THE
MEAN WAS 68 DEGREES AND THE NORMAL 34 DEGREES.

$$

WDM

And, from the Capital Weather Gang (Washington Post blog) yesterday March 21, 2012, posted at 3:11pm:

Pellston, Michigan: After reaching 80 or higher for three straight days - hotter than ever before in March - it reach 84 Tuesday, a phenomenal 29 degrees above its previous record high (55 in 1976 and 1948) and 44 degrees above average. It has at least matched that today, standing at 84 p.m. as of 2 p.m. central time. In Traverse City, the high has reached at least 87 (45 degrees above normal), surpassing the monthly record set just yesterday.