National Weather Service United States Department of Commerce

The historic heat wave during the middle of March has now set one more record by making March 2012 the warmest March ever in Southeast Michigan. Not only did all three climate sites break this record, they broke it by almost three degrees! This means that for all three climate sites, March 2012 will go in the record books as not only the warmest, but also as having broken the highest March temperature and breaking the record for consecutive days with highs above 60, 70 and 80 degrees.

Below is the number of days in which each of the climate sites had high temps at or above 60, 70 and 80 degrees.

 

SITE # Days at or Above 60 # Days at or Above 70 # Days at or above 80
DTW 18 11 3
FNT 18 10 4
MBS 17 10 4

The following is the top 10 list for warmest Marches and year in which they occurred. The numbers represent the average montly temperature (which takes into account both daytime highs and nighttime lows) in degrees Fahrenheit. Normal monthly mean temperatures for March are in the mid 30s.

 

DTW FNT MBS
1.    50.7    (2012) 1.    49.5    (2012) 1.    48.0    (2012)
2.    47.9    (1945) 2.    46.0    (1945) 2.    45.1    (1945)
3.    46.1    (1946) 3.    44.6    (1946) 3.    44.0    (1910)
4.    44.0    (2000) 4.    41.4    (1929) 4.    42.0    (1938)
4.    44.0    (1910) 5.    41.3    (2000) 5.    41.9    (1946)
6.    43.3    (1973) 5.    41.3    (1973) 6.    41.4    (2000)
7.    42.5    (1921) 7.    40.8    (1938) 7.    40.7    (1977)
8.    42.4    (2010) 8.    40.4    (1935) 8.    40.6    (1903)
9.    41.6    (1938) 9.    40.1    (1936) 9.    40.5    (1929)
9.    41.6    (1929) 9.    40.1    (1921)

10.   39.4   (2010)

 

 

Was March 2012 the Most Unusual Month in Southeast Michigan's Recorded History?

When comparing departures from normal over a period as long as an entire climate record, it is useful to compare against a common baseline.  Detroit's average March temperature, using the entire 1874-2011 period as a baseline, is 35.1F.  Flint's average March temperature, from 1921-2011, is 33.8F.  Those time spans include the entire climate record for both locations.  Below is a table containing a comparison of March 2012 to the months that previously held the record for greatest monthly departure. By this measure, March 2012 can, in fact, be considered the most unusual month in SE Michigan's history:

 

  March 2012 Departure from Normal Previous Record
Detroit Area +15.6F (1874-2011 average is 35.1F) -13.9F, February 1875
Flint Area +15.7F (1921-2011 average is 33.8F) -12.6F, March 1960