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Has the climate in Algonquin changed?

How Algonquin's climate has changed

About 0.4°F per decade, measured from Algonquin's official daily weather records, 2011–2025. Individual years still bounce around — some recent ones came in cool — but the long-term line has clearly risen.

Is that a lot? Algonquin's warming is broadly in line with other cities in United States — neither unusually fast nor unusually slow.

What has actually changed

Each card compares the 1970s (the first ten years of the record) with recent years (the last ten) — the same span the headline and the chart use.

Freezing nights
125 more nights
1970s
0 / yr
Recent
125 / yr
Colder winters — more frosts
Average temperature
about the same
1970s
50.8°F
Recent
50.9°F
Year-round temperature has barely moved
Hot days above 90°F
20 more days
1970s
0 / yr
Recent
20 / yr
More days of serious heat
Rainy days
8 fewer days
1970s
104 / yr
Recent
96 / yr
Drier on average

Algonquin's temperature, year by year

Average temperature for each year from 2011 to 2025.

44°46°48°50°52°54°2011: 52.1°F2012: 52.6°F2013: 47.8°F2014: 45.6°F2019: 48.3°F2020: 51.5°F2021: 50.3°F2022: 49.3°F2023: 51.9°F2024: 52.1°F2025: 48.7°Flong-term trend201120202025
a warmer-than-average year a cooler-than-average year

Each bar is one year. Most recent years sit above the older ones. Some recent years still came in cool — warming is a slope, not a straight climb.

In day-to-day terms, that long-term shift shows up as about 39 more freezing nights a year and about 7 more days above 90°F compared with the 1970s.

When in the year the change shows up

How much warmer each month is now than in the 1970s. Useful if you garden or care about a particular season — otherwise the headline above already has the answer.

-0.5°0.0°+0.5°+1.0°+1.5°+2.0°+2.5°+3.0°+3.5°January: +3.1°F+3.1JFebruary: +1.4°F+1.4FMarch: +1.7°F+1.7MApril: +2.0°F+2.0AMay: +1.4°F+1.4MJune: +1.0°F+1.0JJuly: +0.2°F+0.2JAugust: +0.4°F+0.4ASeptember: -0.4°F-0.4SOctober: +0.3°F+0.3ONovember: +0.5°F+0.5NDecember: +2.1°F+2.1D

January has warmed the most — about 3.1°F. The warming runs across the whole year, not just one season.

Methodology & sources

Temperature — the official 1991–2020 climate normals from NOAA's U.S. Climate Normals, measured at Crystal Lake 4nw (NOAA GHCN station USC00112048), about 13 km from the city centre.

How we build these numbers →