May 2025 Upper Mississippi River Weather Summary

Upper Mississippi River Weather Summary for May 2025:

Temperatures - Near to Warmer than Normal

During May 2025, average temperatures ranged from 53.1°F near Hillsboro, WI (COOP) to 59.8°F at Oelwein Municipal Airport, IA (AWOS).
Temperature anomalies ranged from near normal to 2°F warmer than normal.
The hottest temperature was 93°F on May 15 at Boscobel Airport, WI (ASOS) and the coldest temperature was 25°F on May 9 near Hillsboro, WI (COOP).

Precipitation - Drier than Normal

Rainfall amounts ranged from 0.52" at Medford Taylor County Airport, WI (AWOS) to 5.08" near Muscoda, WI (CoCoRaHS).
Rainfall anomalies ranged from 0.5 to 2.5" drier than normal.
The wettest day was May 20 when 2.10" of rain fell near Houston, MN (CoCoRaHS).

Below are the May 2025 climate summaries for La Crosse, WI, and Rochester, MN.

...May 2025 Highlights...

Temperatures - Cooler than Normal

During May 2025, the average temperature was 59.5°F at La Crosse Regional Airport. This was 1.5°F cooler than the 1991-2020 normal of 61°F. This was the coolest May since 2020 when the average temperature was 59.5°F.
The average high temperature was 70.8°F. This was 1.2°F cooler than the 1991-2020 normal of 72°F.
The average low temperature was 48.2°F. This was 1.9°F cooler than the 1991-2020 normal of 50.1°F.
The warmest temperature was 88°F on May 15 and coldest temperature was 38°F on May 24

Precipitation - Drier than Normal

A total of 3.08" of rain fell. This was 1.25" below the 1991-2020 normal of 4.33".
The wettest day was May 20 when 1.70" of rain fell. Just over 55% of the monthly rainfall fell on this day.
Rain fell on 12 days (8 days with measurable and 4 days with a trace).

...Records...

Daily - May 20 - Rainfall total of 1.70". Previous record was 1.46" in 1913. Daily precipitation records go back to October 15, 1872.
Coldest Average Low Temperature for a 3-Day Memorial Day Weekend (May 24-26) - The average low temperature was 40.3°F. The previous record was 41°F in 1979 (May 26-28). These records extend back to 1971.

...Looking ahead to June...

The normal high temperature in La Crosse rises from 78°F on June 1st to 85°F on the 30th. The normal low temperature rises from 56°F on the 1st to 64°F by the end of the month. The normal mean temperature for the month is 71.0°F. La Crosse’s hottest June occurred in 1993 with an average temperature of 76.5°F, and its coldest June occurred in 1969 with an average temperature of 61.4°F.
For June, the hottest temperature was 102°F on June 20, 1933, and June 21, 1988, and the coldest temperature was 33°F on June 1, 1897. There are typically 4 days with temperatures at or above 90°F.
The average precipitation for June is 5.08". The wettest June occurred in 1899 when 11.56" of precipitation fell. The driest June occurred in 1910 when 0.37" of precipitation fell. The wettest June day was 4.50" on June 18, 2011. Normally, there are 7 days with thunderstorms.

...May 2025 Highlights...

Temperatures - Warmer than Normal

During May 2025, the average temperature was 58.9°F at Rochester International Airport. This was 1.3°F warmer than the 1991-2020 normal of 57.6°F. This was the 4th consecutive May to average warmer than normal.
The average high temperature was 69.4°F. This was 1.4°F warmer than the 1991-2020 normal of 68°F.
The average low temperature was 48.5°F. This was 1.4°F warmer than the 1991-2020 normal of 47.1°F.
The warmest temperature was 87°F on May 15 and coldest temperature was 41°F on May 3.

Precipitation - 16th Driest

A total of 1.92" of rain fell. This was 2.43" below the 1991-2020 normal of 4.35". This was the 16th driest May and the driest May 2014 (1.78" - 13th driest). The driest May was in 1934 when only 0.40" of rain fell.
The wettest day was May 20 when 1.42" of rain fell. Just over 58% of the monthly rainfall fell on this day.
Rain fell on 11 days (8 days with measurable and 3 days with a trace).

...Records...

...Looking ahead to June...

The normal high temperature in Rochester rises from 74°F on June 1st to 80°F by the end of the month. The normal low temperature rises from 53°F on the 1st to 61°F by the end of the month. The normal mean temperature for the month is 67.5°F. Rochester’s hottest June occurred in 1933 with an average temperature of 73.9°F, and its coldest June occurred in 1969 with an average temperature of 59.6°F.
For June, the hottest temperature was 105°F on June 27, 1934, and the coldest temperature was 31°F on June 9, 1937. There are typically 2 days with temperatures at or above 90°F.
The average precipitation for June is 5.35". The wettest June occurred in 2000 when 12.51" of precipitation fell. The driest June occurred in 1910 when a trace of precipitation fell. The wettest June day was 4.90" on June 28, 2019. Normally, there are 8 days with thunderstorms.