September
September · June · July
United States · 1991–2020
September leads for comfortable weather in Cedar Mills: typically 22.4°C by day, 10°C at night, with 77 mm of rain. Based on measured 1991–2020 NOAA station history.
September · June · July
July · August · June
September · May · October
The weakest month is January, scoring 5 against September’s 77 — days reach only -5.8°C, 30° 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 | -5.8°C | -15.4°C | 21 mm | 4.3 | 9 h 08 | 5 | Good coverage |
| February | -2.6°C | -12.3°C | 16 mm | 3.3 | 10 h 20 | 5 | Good coverage |
| March | 3.8°C | -5.9°C | 37 mm | 5.3 | 11 h 46 | 5 | Good coverage |
| April | 13.2°C | 1.6°C | 56 mm | 6.3 | 13 h 25 | 34 | Good coverage |
| May | 20.2°C | 8.5°C | 88 mm | 9.5 | 14 h 49 | 63 | Good coverage |
| June | 25.7°C | 14.2°C | 112 mm | 10.2 | 15 h 35 | 76 | Good coverage |
| July | 27.7°C | 16.3°C | 80 mm | 6.7 | 15 h 17 | 76 | Good coverage |
| August | 26.4°C | 14.8°C | 112 mm | 7.8 | 14 h 04 | 76 | Good coverage |
| September | 22.4°C | 10°C | 77 mm | 6.5 | 12 h 28 | 77 | Good coverage |
| October | 14.4°C | 3°C | 55 mm | 6.2 | 10 h 53 | 41 | Good coverage |
| November | 4.3°C | -4.5°C | 35 mm | 4.1 | 9 h 29 | 5 | Good coverage |
| December | -2.7°C | -11.7°C | 19 mm | 3.6 | 8 h 47 | 5 | Good coverage |
| Month | Record high | Record low | Wettest day | Wettest / driest month | Years |
|---|---|---|---|---|---|
| January | 16.1°C24 Jan 1981 | -39.4°C18 Jan 1994 | 64 mm7 Jan 1999 | 88 mm1999 · driest 0 mm in 1974 | 65 |
| February | 15.6°C16 Feb 1981 | -37.8°C2 Feb 1996 | 27 mm14 Feb 1919 | 64 mm1919 · driest 0 mm in 1964 | 64 |
| March | 28.3°C30 Mar 1968 | -35.6°C1 Mar 1962 | 51 mm3 Mar 1965 | 134 mm1965 · driest 2 mm in 1959 | 65 |
| April | 35.0°C21 Apr 1980 | -16.1°C3 Apr 1975 | 70 mm22 Apr 2001 | 166 mm2001 · driest 4 mm in 1987 | 65 |
| May | 37.2°C14 May 2001 | -6.7°C3 May 1967 | 71 mm5 May 1959 | 187 mm1991 · driest 15 mm in 1958 | 64 |
| June | 38.9°C25 Jun 1988 | 0.6°C7 Jun 1901 | 152 mm28 Jun 1997 | 267 mm2002 · driest 2 mm in 1988 | 64 |
| July | 40.6°C24 Jul 1901 | 4.4°C8 Jul 1895 | 88 mm23 Jul 1977 | 237 mm1997 · driest 4 mm in 1898 | 64 |
| August | 40.0°C1 Aug 1988 | -0.6°C30 Aug 1896 | 114 mm26 Aug 1967 | 215 mm2002 · driest 11 mm in 1896 | 64 |
| September | 37.2°C17 Sep 1895 | -8.9°C18 Sep 1896 | 94 mm8 Sep 1991 | 206 mm1900 · driest 5 mm in 2000 | 66 |
| October | 31.7°C1 Oct 1963 | -14.4°C28 Oct 1919 | 61 mm10 Oct 1973 | 147 mm1968 · driest 0 mm in 1895 | 65 |
| November | 27.2°C8 Nov 1999 | -27.8°C26 Nov 1977 | 65 mm1 Nov 1991 | 126 mm1991 · driest 0 mm in 1967 | 65 |
| December | 18.3°C1 Dec 1998 | -36.7°C19 Dec 1983 | 34 mm28 Dec 1959 | 76 mm1918 · driest 0 mm in 1962 | 65 |
| Month | Days 25°C+ | Days 30°C+ | Frost nights | Heavy rain (10 mm+) | Snow days |
|---|---|---|---|---|---|
| January | 0 | 0 | 28 | <1 | 5 |
| February | 0 | 0 | 25 | <1 | 4 |
| March | <1 | 0 | 25 | 1 | 3 |
| April | 2 | <1 | 11 | 2 | 1 |
| May | 6 | 2 | <1 | 3 | 0 |
| June | 19 | 6 | 0 | 3 | 0 |
| July | 25 | 10 | 0 | 3 | 0 |
| August | 22 | 5 | 0 | 3 | 0 |
| September | 12 | 2 | <1 | 2 | 0 |
| October | 2 | <1 | 9 | 2 | <1 |
| November | <1 | 0 | 23 | 1 | 2 |
| December | 0 | 0 | 29 | <1 | 4 |
| Month | Warm & dry days | Wet days | Washouts | Week with 3+ wet days | Daytime mean has ranged |
|---|---|---|---|---|---|
| January | 0% | 12% | 1% | 5% | -10.4–-1.3°C |
| February | 0% | 11% | 1% | 6% | -7.1–1.6°C |
| March | 2% | 17% | 4% | 12% | 0.1–8.2°C |
| April | 17% | 23% | 7% | 21% | 10.4–17.4°C |
| May | 45% | 28% | 9% | 33% | 18.4–23.8°C |
| June | 64% | 31% | 12% | 36% | 23.6–28.0°C |
| July | 76% | 22% | 9% | 19% | 26.5–31.0°C |
| August | 73% | 25% | 10% | 24% | 25.1–29.2°C |
| September | 56% | 22% | 7% | 22% | 20.1–24.4°C |
| October | 24% | 18% | 5% | 15% | 11.8–17.9°C |
| November | 2% | 14% | 3% | 9% | 0.5–8.1°C |
| December | 0% | 11% | 2% | 6% | -7.4–0.8°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