Drought 2009 (updated October 29, 2009)
Minnesota's present drought conditions are the result of two spells of dry weather.
2009 growing season dry spell:
2009 growing season precipitation totals were well short of historical averages across much of Minnesota. Although early-October rains improved the situation in some locales, many Minnesota counties continue to be categorized as Abnormally Dry or undergoing Moderate to Severe drought (map at right). In the drier areas of north central Minnesota, precipitation totals have been roughly 50% to 75% of normal since April 1, falling short of average by six or more inches (maps below).
2008-2009 long-term dry spell: In east central Minnesota, a long-term episode of dryness began in mid-June of 2008 and continued into Autumn 2009. Long-term precipitation deficits in this area range from eight to fourteen inches (map at bottom of page). Affected counties are categorized as experiencing Moderate drought by the U.S. Drought Monitor (map at right).
Weekly rainfall totals through Monday morning, October 26 (map at right) exceeded one inch in many Minnesota counties. The heaviest rains fell in southeastern Minnesota where weekly totals topped three inches. October rainfall totals to-date exceed five inches in many locales in the southern two-thirds of the state, topping the historical October average by more than three inches.
Temperatures last week were again below normal nearly everywhere in Minnesota. October 2009 will be remembered as one of the coldest Octobers on record.
- Agriculture - The Agricultural Statistics Service reports that topsoil moisture is "Short" across only five percent of Minnesota's landscape as of October 25. This represents a 35 percent improvement from late September.
- Stream flow - Stream discharge values for roughly 15 percent of Minnesota measurement sites rank below the 25th percentile in the historical data distribution for the date. Some measurements fall below the 10th percentile when compared with historical late-October values. Some of the lowest flows, relative to historical data, are observed along the upper reaches of the Mississippi River and in northeastern Minnesota.
- Lake and Wetland Levels - Water levels on many Minnesota lakes are very low, especially in east central counties. The White Bear Lake Conservation District reports that White Bear Lake is near its all-time recorded low level. According to the Minnehaha Creek Watershed District, discharge at Lake Minnetonka's Grays Bay Dam, the outlet to Minnehaha Creek, remains suspended per operating procedures. The Prior Lake-Spring Lake Watershed District indicates that Prior Lake water levels are the lowest since the early 1990s. For significant rises to occur in the larger water bodies, above-normal precipitation is needed throughout the autumn and into 2010.
- Wildfire Danger - The Department of Natural Resources - Division of Forestry classifies wildfire danger as Low throughout Minnesota.
2009 seasonal precipitation deficit maps: