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Weather extremes

How extreme does Decatur's weather get?

The hottest, coldest, wettest and snowiest days Decatur has recorded — the outer limits of what its weather can do, and how far they sit beyond a normal day.

Based on 50+ years of daily weather observations (1971–present), from the Decatur Wtp station 1 km away. Updated through May 2026 — an all-time extreme only changes when a more extreme day actually occurs, so some dates are old. That is normal, not stale data.

The four kinds of extreme

The hottest, coldest, wettest and snowiest single days Decatur has recorded — each shown against what a normal day that time of year looks like.

🔥 Hottest day
106°F Aug 20, 1983

That is about 22°F hotter than a normal August afternoon in Decatur (typical high near 84°F).

The three most extreme on record

1 106°F Aug 20, 1983
2 105°F Aug 16, 1988
3 104°F Jul 19, 1980
❄️ Coldest night
-31°F Jan 3, 1999

About 51°F colder than a normal January night in Decatur (typical low near 20°F).

The three most extreme on record

1 -31°F Jan 3, 1999
2 -23°F Jan 17, 1977
3 -22°F Jan 17, 1982
🌧️ Most rain in one day
5.84 in Sep 14, 2008

More rain in a single day than Decatur usually gets in the whole month of September (typical September total about 3.1 in).

The three most extreme on record

1 5.84 in Sep 14, 2008
2 5.11 in Jul 26, 1992
3 4.71 in Aug 2, 1978
Most snow in one day
13.0 in Mar 24, 2013

Close to a whole typical March's snow in one day (Decatur averages about 1 in across the month).

The three most extreme on record

1 13.0 in Mar 24, 2013
2 10.0 in Dec 20, 1973
3 9.0 in Dec 19, 1973

How hot and cold it gets, month by month

The shaded band is the normal range of daily temperatures for each month. The dots show the most extreme it has ever been — so you can see how far beyond a normal day the records really sit.

-50°-30°-10°10°30°50°70°90°110°130° all-time high 106°F JanFebMarAprMayJunJulAugSepOctNovDec
normal range of daily temperatureshottest ever recordedcoldest ever recorded

Decatur's record heat sits well above even a hot day for the season — August's 106°F is about 22°F beyond a normal hot afternoon. Its record cold is just as far below a normal winter night — the dots mark how rare each extreme really is.

In plain terms

In a normal year, Decatur's warmest days reach the mid-80s°F and its coldest nights drop to the low 20s°F. But across the record it has gone as high as 106°F and as low as −31°F. A single day has delivered over 6 inches of rain or close to 13 inches of snow. Those are the outer edges worth knowing if you are moving here, planning a trip, or thinking about a house.
Methodology & sources

Temperature & precipitation — the official 1991–2020 climate normals from NOAA's U.S. Climate Normals, measured at Decatur Wtp (NOAA GHCN station USC00112193), about 1 km from the city centre.

How we build these numbers →