A monthly electronic newsletter summarizing Minnesota's climate conditions and the resulting impact on water resources. Distributed on the first Thursday of the month.
State Climatology Office - DNR Division of Ecological and Water Resources, St. Paul
distributed: September 8, 2025
What happened in August 2025:
- August 2025 continued the fairly wet pattern for the south half of the state, while the north part was a bit drier. The wettest location found so far was at Waseca in Waseca County with 11.27 inches of rain. This was the seventh highest monthly precipitation total on record for Waseca back to 1914. Grand Meadow in Mower County was not far behind with 11.13 inches. One of the driest locations was at Grand Rapids in Itasca County with .53 inches or 2.87 inches below normal. The preliminary statewide average precipitation was 3.79 inches or .18 inches above normal.
[see: August 2025 Precipitation Total Map | August 2025 Precipitation Departure Map | August 2025 Climate Summary Table | August 2025 Percent of Normal Precipitation Map] - There was one weather event of note in August 2025. There were several days of heavy rain in southern Minnesota from August 14-18. Numerous waves of heavy, generally slow-moving thunderstorms combined to drop 2-4 inches of rain across most of southern Minnesota, with isolated areas receiving six inches or more.
[see: Several Days of Heavy Rain in Southern Minnesota: August 14-18, 2025] - It will be close, but it appears as though that August will wind up slightly above normal for temperature, which would be the sixth August in a row that Minnesota finished with above normal temperatures. The preliminary average was 67.9 degrees or .2 degrees above normal. The highest air temperature found so far was 95 degrees at Red Lake Falls on August 9 in northwest Minnesota and the lowest temperature found so far was 32 degrees at Goodridge in Pennington County on August 25th. Weather during the Minnesota State Fair was mostly pleasant with ten days below 80 degrees for a high temperature. There was rain on only one day and that was a fairly light with .08 (eight hundredths of an inch) This was probably the nicest fair weather-wise for temperatures and precipitation since 2009.
[see: Minnesota State Fair Weather] - [see: August 2025 Climate Summary Table | 2025 August Departure from Normal Temperature Map]
Where we stand now:
- Seasonal precipitation totals (April 1 through September 2) generally ranked well above the historical median in west central and south central Minnesota, and below the median over the north.;
[see: Seasonal Precipitation Ranking Map] - The U. S. Drought Monitor map released on September 4 depicts 13% of the state in the Abnormally Dry category. This is almost exactly the same amount of coverage a year ago. The U.S. Drought Monitor index is a blend of science and subjectivity where drought categories (Moderate, Severe, etc.) are based on several indicators.
[see: Drought Conditions Overview] - The U.S. Geological Survey reports normal to much above normal stream flows in the Minnesota, the Red River, and the Mississippi River from the Twin Cities to Winona. There's mostly normal stream flows (the 25th to the 75th percentile) over northern Minnesota, with the St. Louis River in the below normal percentile in the Duluth area and a few other rivers in the central and north, including the Crow Wing River at Nimrod in Wadena County. [see: Cooperative Stream Gauging | USGS Stream Flow Conditions]
- Water levels on Minnesota lakes vary depending on lake and location in the state. Mille Lacs on September 8 was at 10.76 feet, about a half a foot lower than this time last year. On September 8, Minnetonka was at 929.21 feet, within a tenth of a foot of the same level last year at this time. On September 8, 75 cfs was flowing into Minnehaha Creek. Water has been flowing out of Lake Minnetonka into Minnehaha Creek since mid-May. On September 8, White Bear Lake was at 923.23 feet, or one tenth of a foot higher than last year at this time. The level of Lake of the Woods is just below the median band, with a downward trend. Rainy Lake is right in the middle of the median band. Lake Superior was forecasted to be at 601.97 feet on September 7, about two tenths of a foot lower than the long term average of 602.17 feet. ;
[see: Mille Lacs Lake Water Level | Lake Minnetonka Water Level | White Bear Lake Water Level | Lake of the Woods Control Board Basin Data | Corps of Engineers Great Lakes Water Levels - The Agricultural Statistics Service on September 2 reports that topsoil moisture across Minnesota is 1 percent Very Short, 6 percent Short, 75 percent Adequate, and 18 percent Surplus. Available soil water at Lamberton on August 15 was approximately 4.92 inches, .73 inches above normal.
[see: Agricultural Statistics Service Crop Progress and Condition | U. of M. Southwest Research & Outreach Center (Lamberton)] - The potential for wildfires rated by DNR Forestry on September 4, as Low across the entire state except in far northwest Minnesota, where a Moderate potential exists. Historically, 80 percent of all wildfires in Minnesota occur during April and May.
[see: Fire Danger Rating Map]
Future prospects:
- The September precipitation outlook has a slight tendency for above normal precipitation over southwest and south central Minnesota, otherwise the rest of the state has equal chances for above normal and below normal precipitation. across the state. September precipitation normal values range from about one-and-a-half inches in northwest Minnesota to about four inches in northeast and southeastern counties.
[see: Climate Prediction Center 30-day Outlook | September Precipitation Normal Map] - Even though it hasn’t started out warm in September so far, The September temperature outlook has a tendency for above normal temperatures over all but the southeast and northeast parts of the state. In the Twin Cities, eleven of the last thirteen Septembers from 2012 to 2024 were above normal for average temperature. Normal September high temperatures are in the middle to upper 70s to start the month, dropping to the low to mid 60s by month's end. Normal lows are in the 50s early in the month, falling to the middle 30s to mid-40s by late September.
[see: Climate Prediction Center 30-day Outlook | September Temperature Normal Map] - The 90-day precipitation outlook for September through November indicates an equal chance for above, below and normal precipitation across the state. The September through November temperature projection offers a tendency for above-normal conditions statewide, except the northwest, where there are equal chances for above normal and below normal temperatures. [see: Climate Prediction Center 90-day Outlook]
- The Winter Outlook (December-February) from the Climate Prediction Center depicts equal chances of below normal, normal, and above normal temperatures and precipitation over the entire state. There is a slight tilt for above normal precipitation across the eastern half of the state. A weak La Niña is expected to be present this winter.
[see: Climate Prediction Center 3.5 month Outlook] - The National Weather Service produces long-range probabilistic river stage and discharge outlooks for the Red River, Minnesota River, and Mississippi River basins. These products address both high flow and low flow probabilities.
[see: National Weather Service - North Central River Forecast Center]
From the author:
- There was a bit of an uptick in tornado reports in Minnesota In 2025 with a preliminary total of 55 fairly weak tornadoes as of September 8. The 1991-2020 average in Minnesota for a season is 46. In 2024, there were 30.
Upcoming dates of note:
- September 18: National Weather Service releases 30/90 day temperature and precipitation outlooks
Subscribe to email announcements of the monthly posting of this product.