All-time weather records — Sullivan, WI
Climate change signal in Sullivan
of Sullivan's all-time daily heat records were set in the last decade (131 of 366 records since 2015).
of all-time daily cold records were set in the last decade (118 of 366 records since 2015).
If records were spread evenly across the station's history, you'd expect roughly 5% per decade. Decade-by-decade, here's where each record-breaking day was set:
| Decade | Heat records set | # | Cold records set | # |
|---|---|---|---|---|
| 1990s | 81 | 53 | ||
| 2000s | 104 | 140 | ||
| 2010s | 95 | 109 | ||
| 2020s | 86 | 64 |
Records are the all-time daily extremes that are still standing — each daily record can only be held by one year. The station's earliest hot record was set in 1995, the latest in 2026. Period of observation: 1995-2026.
Records by month
| Month | Hottest day | Coldest day | Wettest day |
|---|---|---|---|
| January | 60.1°F — Jan 5, 1997 | -29.9°F — Jan 31, 2019 | 2.06 in — Jan 29, 2013 |
| February | 71.1°F — Feb 27, 2024 | -29.0°F — Feb 4, 1996 | 1.64 in — Feb 27, 2023 |
| March | 81.0°F — Mar 27, 2007 | -13.0°F — Mar 4, 2002 | 2.32 in — Mar 31, 1998 |
| April | 89.1°F — Apr 19, 2002 | 12.9°F — Apr 5, 2018 | 2.40 in — Apr 23, 1999 |
| May | 95.0°F — May 27, 2012 | 21.9°F — May 9, 2020 | 4.93 in — May 12, 2014 |
| June | 99.0°F — Jun 28, 2012 | 33.1°F — Jun 1, 2003 | 3.80 in — Jun 8, 2008 |
| July | 106.0°F — Jul 5, 2012 | 41.0°F — Jul 2, 2001 | 4.70 in — Jul 23, 2010 |
| August | 98.1°F — Aug 1, 2001 | 39.9°F — Aug 21, 2004 | 4.09 in — Aug 19, 2007 |
| September | 96.1°F — Sep 14, 1998 | 28.9°F — Sep 15, 2007 | 3.47 in — Sep 11, 2022 |
| October | 90.0°F — Oct 6, 1997 | 19.0°F — Oct 31, 2019 | 2.05 in — Oct 26, 2016 |
| November | 75.0°F — Nov 3, 2015 | -2.0°F — Nov 29, 1995 | 3.41 in — Nov 6, 2005 |
| December | 66.9°F — Dec 6, 2001 | -16.1°F — Dec 19, 2016 | 1.39 in — Dec 28, 2015 |
Click a month to see every daily record for that month in Sullivan.