Record heat continues in Fond du Lac area

The City of Fond du Lac hit a new daily record high temperature yesterday, Friday, October 3, 2025, when the mercury climbed to 87 degrees, breaking the old record of 85 degrees which occurred in 1953.

Saturday not only has a chance of breaking another daily record with a high forecasted to be 90 degrees, breaking the record for October 4th set in 1967 when it hit 86 degrees, but we also have the chance to hit the all time hottest temperature in October as well.

Only once before has the temperature hit the 90 degree mark in Fond du Lac in October, and that was in 1963 on October 6th. Reaching our forecasted high of 90 today will tie our all-time high for October but hitting 91 will set a new record.

This heat is due to an ongoing weather pattern that’s been in place for the last couple weeks.

The mid level jet stream is flowing much farther north than it would normally be this time of year. This jet stream generally separates cooler air to its north and warmer air to its south. This flow, moving well north into Canada, has allowed for warmer air from the south to move into our area and even farther north with low 70s extending all the way into southern Ontario.

In contrast, where the jet stream is dipping south in the western US, temperatures are much cooler with highs only in the 50s in northern California and Nevada.

This jet stream is also what steers weather systems so any rainfall has missed us to the north for the most part over the last two weeks.

As high pressure moves to our east and a low pressure system sits to our west, we sit snug in-between the two with southerly winds and clear skies which will bring us our warmest temperatures of this stretch of warmer than normal weather.

These warmer than normal temperatures come to a screeching halt Monday however after the low to our west moves to our northwest into Canada. This will cause a cold front to sweep across Wisconsin from north to south early Monday morning which will bring our high temperatures closer to normal for this time of year, in the 60s.