Illinois State Water Survey Illinois State Climatologist

Cold November Brings an End to Meteorological Autumn

November temperatures were well below the long-term average across the state, breaking hundreds of local daily records. The preliminary statewide November average temperature was 35.6 degrees, about 7 degrees below our 30-year normal and tied for the ninth coldest on record. Preliminary data suggest November was drier than average for most of the state. The […]

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October: Heat to Snow

We saw highly variable temperatures across the state this month, with record-breaking heat in the early part of October, and record-breaking cold in the latter part. The preliminary statewide October average temperature was 53.7 degrees, less than 1 degree below our 30-year normal. Temperatures were near normal in eastern Illinois, and between 2 and 6 […]

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September Heat, Flooding, & Drought

This past month was tied for the 4th warmest September for Illinois (state average temperatures back to 1895), and the warmest September since 1933. Precipitation varied tremendously from north to south across the state. Preliminary data suggest that September was tied for the 4th warmest on record for Illinois. The preliminary average statewide September temperature […]

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Illinois First Fall Freeze Climatology

Due to significant planting delays across most of the Midwest this year, I have heard many concerns about an early fall freeze and its potential effects on immature crops. Most plants experience damage from a hard freeze or “killing freeze”, which is typically designated by a daily minimum air temperature at or below 28°F. Even […]

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