Is this weather normal in Sully County?

South Dakota · county records since 1895, through September 2026.

Weather › South Dakota › Sully County

10 of the last 12 months ran warmer than usual in Sully County. Sully County has warmed about 0.4° per decade since 1970.

This week

Usual for Oct 28 to Nov 3: highs near 51°, lows near 28°

That is the 1991 to 2020 average for these dates in Sully County. The Weather Service forecast fills in below.

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usual high for the datewarmercooler

The last 12 months

Oct: +4.9°OctNov: +3.8°NovDec: +3.8°DecJan 2026: +2.4°JanFeb: +10.8°FebMar: +7.0°MarApr: -0.6°AprMay: +1.2°MayJun: -0.6°JunJul: +4.4°JulAug: +0.2°AugSep: +3.4°Sepwarmercooler

Each bar is a month's average temperature against the usual for that month (1991 to 2020). Ranks compare the same month in every year since 1895.

Every year since 1895

18952025

Rain and drought

Oct: -1.1 inOctNov: +0.3 inNovDec: -0.0 inDecJan 2026: -0.2 inJanFeb: -0.5 inFebMar: -0.4 inMarApr: -0.3 inAprMay: -1.5 inMayJun: -0.5 inJunJul: -0.9 inJulAug: +0.3 inAugSep: +1.4 inSepwetterdrier

Rain and melted snow against the usual for each month. The drought reading is NOAA's Palmer index for the county.

Month by month in Sully County

MonthUsual high / lowUsual rainWarmestColdest
January27° / 7°0.4 in32.4° 2006-4.9° 1937
February31° / 10°0.6 in36.4° 1954-7.6° 1936
March44° / 21°0.8 in47.0° 201212.8° 1899
April57° / 32°1.8 in52.9° 195535.5° 1920
May69° / 43°3.0 in68.8° 193448.7° 1907
June79° / 54°3.4 in77.4° 193359.2° 1945
July86° / 60°2.6 in85.0° 193663.9° 1992
August85° / 58°2.2 in78.5° 193764.9° 1915
September76° / 48°1.7 in69.2° 189750.3° 1965
October60° / 35°1.7 in57.3° 196336.2° 1925
November44° / 22°0.5 in41.7° 199911.6° 1896
December31° / 11°0.4 in30.5° 20230.9° 1927

Warmest and coldest are the month's whole-month average temperature, with the year it happened.

Towns in Sully County

Nearby counties