Early Cold Preview Yielded to Warmth Last Two-Thirds of September

The start of September was an October preview with a record cool high of 57 and a record cool average of 48 set on September 4 (low temperature of 38). There were 5 straight days at least 11 degrees cooler than average. However, that wedge of cool air moved out, allowing a couple of days of near average temperatures. Temperatures quickly warmed from there as high pressure persisted in the central US. There were 11 days, including yesterday, during which the temperatures were at least 10 degrees warmer than average. The result was St. Cloud's 28th warmer than average month in the 29 months since April 2023. The final September average temperature was 64.6 degrees (average high: 76.1 degrees; average low: 53.0 degrees), 4.9 degrees above average. That kept September 2025 short of September 2024's record warmth. However, September 2025 was the 11th warmest September in St. Cloud records.

That warmth included a high of 91 degrees on September 16, the 7th 90-degree high of the warm season. That temperature fell 3 degrees short of the September 16 record warm high. However, September 29's high of 88 degrees did break the daily warm record. There were 9 highs of 80 degrees or highs; the September average is 6 such days. That brings the seasonal total to 69 days, 6 days above average.

However, much of the warmth was held in another swath of low temperatures of 60 degrees and milder. There were 11 days with a low of at least 60 degrees. That tied the 1897 record for the most 60-degree September lows. For the entire warm season, St. Cloud has seen 61 lows of at least 60 degrees, tied for the 3rd most lows that warm. The record of 64 days was set in 1900 (see table below). There were 2 more lows of 65 degrees and warmer, pushing the warm season total to 25 days, tied for the 9th most on record. Again, the persistent humidity, despite a lack of rain, was responsible for the mild low temperatures, as has been the case all year.

Dry September Continued Recent Trend of Years

September 2025 continued the recent trend of drier conditions ranging from sometime during the middle and late summer into the fall. The September St. Cloud rainfall was 1.66 inch, only a little above half of the average (3.01 inches). This drier spell began in August, since the August-September total of 3.45 inches is 3.56 inches below average. It doesn't beat last year's September (3rd driest September on record), but 2025 now has the 17th driest August-September combination in St. Cloud records.

These dry trends during at least the last part of the growing season have included:

• Sept-Oct 2024: 1.55 inch, 4.11 inch below average
• May 1-Sept 22, 2023: 7.97 inches, 9.86 below average (most of the growing season)
• Sept-Oct 2022: 2.54 inches, 3.08 below average
• May 1-August 19, 2021: 6.03 inches, 7.77 inches below average (most of spring and summer)
• 2020 growing season (April-October): 20.69 inches, 2.55 below average (modest shortfall during growing season)

Some parts of western and southernMinnesota had some heavy August rain, so they have over 8 inches of precipitation in August and September (yellow areas when you set the NWS Water Prediction Service date to September 30 and the time period to 60 days), but the eastern portion of the Minnesota River Valley (Redwood Falls through Mankato and the Twin Cities) and the bulk of northern Minnesota (medium or light green) have been short on rainfall. Note that St. Cloud had 16.24 inches in May through August, more than 5 inches over the 11.01 inch average. Only parts of north central Minnesota have shown up in the yellow, abnormally dry, category of the US Drought Monitor with some possibility of brown in tomorrow's update (compare September 30 after tomorrow to July 29).

In the short-term, the dry warmth will continue through much of this weekend, which includes Minnesota's most favored period of high pressure (last week of September, first week of October). Record warm lows are possible each day with lows in the 60's and record warm highs may be reached on Friday and Saturday (highs in the upper 80's to lower 90's). However, we may be suffering another early month case of weather whiplash in October, as highs during the first part of next week could be in the 60's or even 50's. A first frost could be possible if we have a clear and calm night.

    September 2025 Statistics

 Last Updated: October 1, 2025