September
September · May · June
United States · 1991–2020
September leads for comfortable weather in Nauvoo: typically 25.3°C by day, 14.4°C at night, with 89 mm of rain. Based on measured 1991–2020 NOAA station history.
September · May · June
August · July · June
October · April · September
The weakest month is January, scoring 5 against September’s 84 — days reach only 0.7°C, 23° below the 24°C the score treats as ideal.
Month by month
The bars show the comfort score. Day and night temperatures come from daily observed highs and lows; rain is the historical monthly estimate.
| Month | Day | Night | Rain | Wet days | Daylight | Comfort | Coverage |
|---|---|---|---|---|---|---|---|
| January | 0.7°C | -8°C | 43 mm | 6.2 | 9 h 34 | 5 | Strong coverage |
| February | 3.3°C | -5.8°C | 49 mm | 5.7 | 10 h 35 | 5 | Strong coverage |
| March | 10.2°C | 0.2°C | 70 mm | 7.4 | 11 h 49 | 19 | Strong coverage |
| April | 17°C | 6.3°C | 103 mm | 9.7 | 13 h 14 | 46 | Strong coverage |
| May | 22.6°C | 12.5°C | 133 mm | 10.5 | 14 h 25 | 71 | Strong coverage |
| June | 27.8°C | 17.9°C | 129 mm | 8.9 | 15 h 03 | 64 | Strong coverage |
| July | 29.7°C | 20.1°C | 103 mm | 7.6 | 14 h 48 | 58 | Strong coverage |
| August | 29°C | 19.1°C | 96 mm | 7.1 | 13 h 47 | 64 | Strong coverage |
| September | 25.3°C | 14.4°C | 89 mm | 6 | 12 h 25 | 84 | Strong coverage |
| October | 18.1°C | 7.8°C | 78 mm | 7 | 11 h 03 | 58 | Strong coverage |
| November | 10°C | 0.9°C | 62 mm | 6.2 | 9 h 52 | 22 | Strong coverage |
| December | 3.4°C | -4.8°C | 51 mm | 6.2 | 9 h 17 | 5 | Strong coverage |
What has changed
Each bar compares the 2011–2025 daytime average for that month against the same month in 1961–1990, measured at the same station. Months where the older record is too thin to compare are left blank.
| Month | Record high | Record low | Wettest day | Wettest / driest month | Years |
|---|---|---|---|---|---|
| January | 19.4°C22 Jan 1957 | -30.6°C10 Jan 1982 | 57 mm20 Jan 1904 | 145 mm1965 · driest 0 mm in 1981 | 79 |
| February | 22.8°C27 Feb 2026 | -29.4°C9 Feb 1979 | 57 mm20 Feb 2014 | 123 mm1997 · driest 1 mm in 2026 | 79 |
| March | 31.1°C26 Mar 2026 | -23.9°C1 Mar 1962 | 86 mm4 Mar 1985 | 156 mm1985 · driest 0 mm in 1978 | 77 |
| April | 33.9°C30 Apr 1895 | -11.7°C6 Apr 1982 | 76 mm2 Apr 1983 | 225 mm1954 · driest 14 mm in 1985 | 77 |
| May | 35.0°C10 May 1895 | -5.6°C11 May 1966 | 103 mm27 May 1996 | 311 mm1996 · driest 15 mm in 1964 | 77 |
| June | 40.0°C25 Jun 1988 | 5.0°C2 Jun 1956 | 124 mm24 Jun 1993 | 278 mm2010 · driest 2 mm in 1963 | 77 |
| July | 41.7°C26 Jul 1916 | 8.3°C30 Jul 1971 | 103 mm19 Jul 1961 | 327 mm1993 · driest 1 mm in 2026 | 82 |
| August | 40.0°C18 Aug 1983 | 5.6°C13 Aug 1977 | 216 mm6 Aug 1959 | 357 mm1970 · driest 0 mm in 2013 | 78 |
| September | 37.8°C2 Sep 2000 | -0.6°C26 Sep 1984 | 110 mm13 Sep 1961 | 456 mm1970 · driest 8 mm in 2017 | 78 |
| October | 33.3°C2 Oct 1953 | -9.4°C19 Oct 1972 | 84 mm13 Oct 1969 | 222 mm1969 · driest 1 mm in 1964 | 79 |
| November | 27.2°C1 Nov 1968 | -20.6°C30 Nov 1964 | 79 mm27 Nov 1990 | 213 mm1985 · driest 3 mm in 1955 | 78 |
| December | 21.1°C4 Dec 1970 | -28.3°C19 Dec 1983 | 76 mm2 Dec 1982 | 159 mm1982 · driest 3 mm in 1954 | 79 |
| Month | Days 25°C+ | Days 30°C+ | Frost nights | Heavy rain (10 mm+) | Snow days |
|---|---|---|---|---|---|
| January | 0 | 0 | 28 | 1 | 4 |
| February | 0 | 0 | 23 | 2 | 3 |
| March | <1 | 0 | 16 | 2 | 1 |
| April | 2 | <1 | 3 | 4 | <1 |
| May | 11 | 2 | 0 | 4 | 0 |
| June | 24 | 10 | 0 | 4 | 0 |
| July | 29 | 15 | 0 | 3 | 0 |
| August | 28 | 13 | 0 | 3 | 0 |
| September | 17 | 5 | 0 | 3 | 0 |
| October | 4 | <1 | 2 | 2 | <1 |
| November | 0 | 0 | 13 | 2 | <1 |
| December | 0 | 0 | 25 | 2 | 3 |
The best month has moved. On the 1961–1990 numbers the strongest month here was May (scoring 80); on 2011–2025 it is September (88). Both are scored the same way, from the same station — only the climate underneath changed.
| Month | Warm & dry days | Wet days | Washouts | Week with 3+ wet days | Daytime mean has ranged |
|---|---|---|---|---|---|
| January | 0% | 17% | 4% | 12% | -3.2–4.0°C |
| February | <1% | 17% | 5% | 12% | -1.4–7.2°C |
| March | 6% | 22% | 7% | 23% | 6.9–12.6°C |
| April | 26% | 30% | 11% | 35% | 14.5–20.3°C |
| May | 52% | 31% | 12% | 37% | 20.3–26.1°C |
| June | 71% | 28% | 13% | 30% | 26.1–30.0°C |
| July | 75% | 25% | 11% | 23% | 27.7–32.8°C |
| August | 77% | 23% | 10% | 20% | 27.2–30.9°C |
| September | 71% | 22% | 11% | 21% | 23.5–27.8°C |
| October | 37% | 20% | 8% | 20% | 16.4–21.1°C |
| November | 7% | 18% | 7% | 15% | 6.5–13.2°C |
| December | <1% | 19% | 5% | 14% | 0.5–6.4°C |
A warm and dry day reaches 20°C with under 1 mm of rain; a wet day gets 1 mm or more; a washout gets 10 mm or more. The week column is the share of seven-day stretches in that month, across the station’s whole daily record, that contained three or more wet days — the odds a week-long trip is rained on repeatedly, counted rather than modelled. The last column is the 10th to 90th percentile of that month’s daytime average across individual years: a narrow band means the average is what you will get, a wide one means the average is a midpoint between years that felt quite different.
The evidence behind this page