Marathon County Severe Weather Facts (1950-2023)
Updated: 01/01/24: Next Update: January 2025
Storm Reports by Decade
Since 1950 there have been 535 documented reports of large hail, damaging winds and
tornadoes across Marathon County. I did include a report from 1921 in this document
which is the state record hail stone of 5.7 inches was set on May 22, 1921. The
population boom of the 1980s and 1990s combined with the SKYWARN program led
to an increase in the number of reports of severe weather during both decades. The
number of reports increased 7% from the 2014-2023 period compared to the 1990s.
One can’t say for sure there has been an increase in severe weather across northeast
Wisconsin. One possible reason for the apparent increase in reports is that in some
instances, multiple reports were received from a single location for the same storm due
to more spotters today. Another reason for the increase in storm reports has been the
focus by the National Weather Service (NWS) to improve warning verification. 2002
was the most active year with thirty-three reports followed by twenty-six reports in
1998, twenty-four reports in 2012 and 2021, nineteen reports in 2006, eighteen reports
in 1997 and 2005, and seventeen reports in 2010. The last time no severe weather was
reported during the year was in 1967. In 2023, there were 14 reports of large hail and
one strong wind/wind damage report.
Days of Severe Weather by Decade
In-order to address the impact of multiple reports for the same storm, the data was
examined by the number of severe weather days. Since the reports were sporadic during
the 1950s through the 1970s, only data from 1980 to present was used. There has been
a 11% increase in the number of days of severe weather from the 2014-2023 period
compared to the 1990s. This trend can be attributed to the increase in population,
technology advances in reporting severe weather, and greater severe weather awareness
by the public. Since 2010, Marathon County averages 5.1 days of severe weather per
year. The long-term average from 1980-2023 is 4.8 days. The most active year was
2002 with ten days of severe weather; followed by nine days of severe weather in 1998
and 2021, eight days in 1999, and seven days in 1984, 2004, 2006, 2011, 2016 and
2018. In 2023, there were five days of severe weather: May 6, July 27, July 28, August
11 and October 24. An unusually large hail was reported across portions of central and
northeast Wisconsin on October 24
th
.