May 2026 Climate Summary

Upper Mississippi River Climate Summary for May 2026:

Temperatures - Near Normal

During April 2026, average temperatures ranged from 52.4°F near Owen, WI (COOP) to 60.7°F at Decorah, IA (COOP). Temperature anomalies ranged from 2°F below normal to 3°F above normal. There was a 72°F difference between the warmest and coldest temperatures in the Upper Mississippi River Valley. The warmest temperature was 92°F at Black River Falls (RAWS) on May 26.  The coldest temperature was 20°F at Rushford, MN on May 7.

Precipitation - Drier than Normal

Precipitation totals varied from 0.25" at near Rochester International Airport, MN (COOP) to 3.75" near Chatfield, MN (CoCoRaHS). Precipitation anomalies ranged from 1" to 5" drier than normal. The highest one-day precipitation was 1.70" near Chatfield, MN (CoCoRaHS) from May 26 through May 27.

Severe Weather -  Near to Above Average

Severe Thunderstorm Warnngs - Near Normal  During May 2026, 19 warnings on 4 days. This was below the 1986-2026 May average of 21 warnings. Severe Thunderstorm Warnings were issued on May 15 (8 warnings), May 17 (7 warnings), May 26 (1 warning), and May 27 (3 warnings). During May, the most was 64 warnings in 1998 and the least was 0 warnings in 1986 and1990.
Tornado Warnings - Tied for the 10th Most  During May 2026, 5 warnings on 4 days. This was below the 1986-2026 May average of 2.8 warnings. Tied with 1998 and 2008 for the 10th most in a May. Tornado Warnings were issued on May 15 (2 warnings) and May 17 (3 warnings). During May, the most was 16 warnings in 2013 and the least was 0 warnings in 17 Mays.
Daily Breakdown of Severe Weather in April 2026 - 4 days May 15 - 10 warnings (8 Severe Thunderstorm Warnings & 2 Tornado Warnings) May 17 - 10 warnings (7 Severe Thunderstorm Warnings & 3 Tornado Warnings) May 27 - 3 warnings (3 Severe Thunderstorm Warnings) May 26 - 1 warning (1 Severe Thunderstorm Warning)

Below are the May 2026 climate summaries for La Crosse, WI, and Rochester, MN.

La Crosse, WI

May 2026 was Slightly Cooler and Much Drier than Normal in La Crosse WI

...May 2026 Highlights...

Temperatures - Slightly Cooler than Normal

• During May 2026, La Crosse Regional Airport had an average temperature of 60.6°F.
• This was 0.4°F cooler than the 1991-2020 normal of 61°F.
• The average high temperature 72.8°F. This was 0.8°F warmer than the 1991-2020 normal of 72°F.
• The average low temperature 48.3°F. This was 1.8°F colder than the 1991-2020 normal of 50.1°F.
• The warmest temperature was 90°F on May 26 and May 27. The coldest temperature was 30°F on May 7.

Precipitation - 10th Driest

• Only 1.18 inches of rain fell. This was 3.15" below the 1991-2020 normal of 4.33".
• This was the 10th driest May and the driest May since 1988 (6th driest May with 0.94").
• The table below lists the 10 driest Mays for La Crosse, WI.

       Driest Mays
    for La Crosse, WI
        1873-2026
         
Rank  Precipitation    Year
----  -------------    ----
  1    0.50 inches     1887
  2    0.69 inches     1891
  3    0.84 inches     1925
  4    0.89 inches     1886
  5    0.91 inches     1934
  6    0.94 inches     1988
  7    1.07 inches     1958
  8    1.08 inches     1985
  9    1.10 inches     1898
 10    1.18 inches     2026

• The wettest day 0.51" on May 17.
• Measurable rain fell on 6 days (19.4%) and trace amounts fell on another 7 days (22.6%).

Snowfall - Normal

• No snow fell. This was normal.
• Only 8 Mays have had measurable snow.
• The last one was in 2013 with 0.8". 1935 had the most snow in May with 7.2".

Mississippi River at La Crosse, WI - Below Normal

• Average May 7 am stage was 6.22 feet.
• This was 1.33 feet below the 1937-2026 average of 7.55 feet.
• For May 2026, the lowest 7 am stage was 5.24 feet on May 30, and highest was 7.74 feet on May 4 and May 5.
• During any May, the lowest 7 am stage was 4 feet on May 18, 1946. Meanwhile, the highest 7 am stage was 15.10 feet on May 1, 2001. 

...Records...

• None.

...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.

Rochester, MN
 

May 2026 was Warmer and Much Drier than Normal in Rochester MN

...May 2026 Highlights...

Temperatures - Warmer than Normal

• During May 2026, Rochester International Airport had an average temperature of 58.6°F.
• This was 1°F warmer than the 1991-2020 normal of 57.6°F.
• The average high temperature 70.3°F. This was 2.3°F warmer than the 1991-2020 normal of 68°F.
• The average low temperature 46.9°F. This was 0.2°F cooler than the 1991-2020 normal of 47.1°F.
• The warmest temperature was 88°F on May 26. The coldest temperature was 30°F on May 6.

Precipitation -  2nd Driest

Only 0.86" of rain fell. This was 3.49" below the 1991-2020 normal of 4.35". This was the 2nd driest May. Only 1934 was drier with 0.40". The table below lists the 10 driest Mays for Rochester MN.

       Driest Mays
    for Rochester, MN
        1886-2026
         
Rank  Precipitation    Year
----  -------------    ----
  1    0.40 inches     1934
  2    0.86 inches     2026
  3    1.17 inches     1963
  4    1.23 inches     1948
  5    1.36 inches     1967
  6    1.47 inches     2002
  7    1.52 inches     1950
  8    1.54 inches     1966
  9    1.56 inches     1887
 10    1.60 inches     1992

The wettest day 0.37" on May 17.

Measurable rain fell on 9 days (29%) and trace amounts fell on another 6 days (19.4% percent).

Snowfall - Normal

• No snow fell.
• This was 0.5" below the 1990-2020 normal of 0.5".
• Only 10 Mays have had measurable snow. The last one was in 2013 with 14.5 inches. That May was the snowiest. The previous record was 2" in 1944.

...Records...

• None

...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.