September 2011 will be the driest September in the modern record back to 1891 with only .36 inches of rain reported in the month. This breaks the old record of .41 inches that was set back in 1940. One has to go back to 1882 to find a September that was drier with .27 inches. The reason for the lack of rainfall is a stagnant weather pattern in September.
The two month precipitation deficit for the Twin Cities from August 1 to September 30 is 3.90 inches. This has made for some brown lawns and declining water levels in lakes.
Scant precipitation also fell across southern Minnesota, intensifying the drought there during the month. The first half of September was dry over northern Minnesota, intensifying the drought there as well. Enough rain fell in the past two weeks over northern Minnesota to stop the dry conditions from worsening. As of September 27 drought conditions persist in northern and southern Minnesota.
Top Ten Driest Septembers for the Twin Cities 1837-2011 Rank Value Year --------------------- 1 0.27 1882 2 0.36 2011 3 0.41 1940 4 0.42 1952 5 0.46 2009 6 0.49 1969 7 0.51 1889 8 0.55 1953 9 0.58 1974 10 0.63 1967