September
September · July · June
United States · 1991–2020
September leads for comfortable weather in Potlatch: typically 23.4°C by day, 4.9°C at night, with 25 mm of rain. Based on measured 1991–2020 NOAA station history.
September · July · June
August · July · September
June · September · May
The weakest month is January, scoring 5 against September’s 80 — days reach only 2.8°C, 21° 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 | 2.8°C | -4.1°C | 62 mm | 8.4 | 8 h 54 | 5 | Strong coverage |
| February | 5°C | -3.5°C | 54 mm | 7.1 | 10 h 13 | 5 | Strong coverage |
| March | 8.9°C | -1.7°C | 61 mm | 9.3 | 11 h 45 | 11 | Strong coverage |
| April | 13.4°C | 0.7°C | 57 mm | 8.3 | 13 h 31 | 31 | Strong coverage |
| May | 18.6°C | 4°C | 61 mm | 7.3 | 15 h 01 | 55 | Strong coverage |
| June | 21.4°C | 6.8°C | 42 mm | 6.3 | 15 h 51 | 73 | Strong coverage |
| July | 27.8°C | 9.2°C | 22 mm | 3.1 | 15 h 31 | 77 | Strong coverage |
| August | 28.7°C | 8.4°C | 18 mm | 2.5 | 14 h 13 | 73 | Strong coverage |
| September | 23.4°C | 4.9°C | 25 mm | 3.4 | 12 h 30 | 80 | Strong coverage |
| October | 14.8°C | 0.9°C | 57 mm | 7.2 | 10 h 48 | 37 | Strong coverage |
| November | 7°C | -1.2°C | 76 mm | 9.4 | 9 h 17 | 5 | Strong coverage |
| December | 2°C | -4.5°C | 76 mm | 7.6 | 8 h 32 | 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 | 16.7°C27 Jan 2015 | -34.4°C31 Jan 1950 | 53 mm6 Jan 1964 | 200 mm1970 · driest 4 mm in 1985 | 102 |
| February | 18.3°C19 Feb 1958 | -32.8°C1 Feb 1996 | 45 mm26 Feb 1948 | 158 mm1999 · driest 7 mm in 1920 | 102 |
| March | 24.4°C28 Mar 2025 | -25.0°C5 Mar 1955 | 29 mm25 Mar 1916 | 183 mm1916 · driest 3 mm in 1996 | 103 |
| April | 32.2°C25 Apr 1946 | -9.4°C19 Apr 1966 | 33 mm4 Apr 1999 | 117 mm1996 · driest 9 mm in 1973 | 103 |
| May | 35.0°C25 May 1928 | -7.8°C1 May 1954 | 41 mm12 May 1998 | 184 mm1998 · driest 2 mm in 1924 | 103 |
| June | 41.7°C30 Jun 2021 | -3.9°C26 Jun 1976 | 65 mm1 Jun 1923 | 131 mm1923 · driest 0 mm in 1932 | 103 |
| July | 40.0°C20 Jul 1931 | -2.8°C7 Jul 1977 | 53 mm24 Jul 1994 | 96 mm1948 · driest 0 mm in 1945 | 104 |
| August | 43.3°C4 Aug 1961 | -3.9°C29 Aug 1980 | 58 mm22 Aug 1992 | 109 mm1989 · driest 0 mm in 1928 | 102 |
| September | 40.0°C1 Sep 2022 | -10.0°C24 Sep 1926 | 51 mm23 Sep 1926 | 132 mm1947 · driest 0 mm in 2012 | 101 |
| October | 32.2°C2 Oct 1987 | -12.8°C29 Oct 1971 | 49 mm27 Oct 1994 | 154 mm2016 · driest 0 mm in 1987 | 100 |
| November | 21.7°C2 Nov 1917 | -26.7°C16 Nov 1955 | 91 mm6 Nov 2022 | 189 mm1973 · driest 1 mm in 1929 | 101 |
| December | 18.3°C6 Dec 1939 | -33.9°C29 Dec 1968 | 56 mm30 Dec 2017 | 185 mm1996 · driest 3 mm in 2008 | 101 |
| Month | Days 25°C+ | Days 30°C+ | Frost nights | Heavy rain (10 mm+) | Snow days |
|---|---|---|---|---|---|
| January | 0 | 0 | 25 | 2 | 5 |
| February | 0 | 0 | 22 | 2 | 3 |
| March | 0 | 0 | 22 | 2 | 2 |
| April | <1 | 0 | 14 | 2 | <1 |
| May | 4 | <1 | 5 | 2 | <1 |
| June | 7 | 2 | <1 | 1 | 0 |
| July | 22 | 11 | 0 | <1 | 0 |
| August | 23 | 12 | <1 | <1 | 0 |
| September | 12 | 4 | 4 | <1 | 0 |
| October | 1 | <1 | 13 | 2 | <1 |
| November | 0 | 0 | 19 | 3 | 2 |
| December | 0 | 0 | 25 | 3 | 5 |
The best month has moved. On the 1961–1990 numbers the strongest month here was June (scoring 78); on 2011–2025 it is September (84). 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% | 35% | 7% | 47% | -0.8–5.5°C |
| February | 0% | 33% | 6% | 42% | 1.9–7.9°C |
| March | 2% | 33% | 5% | 42% | 6.6–11.7°C |
| April | 15% | 28% | 5% | 32% | 11.3–17.5°C |
| May | 40% | 25% | 5% | 28% | 16.1–21.8°C |
| June | 62% | 21% | 5% | 22% | 20.1–25.3°C |
| July | 89% | 9% | 2% | 4% | 25.7–30.9°C |
| August | 89% | 10% | 2% | 7% | 25.4–30.7°C |
| September | 66% | 15% | 4% | 14% | 19.0–26.2°C |
| October | 25% | 23% | 5% | 28% | 13.0–19.1°C |
| November | <1% | 36% | 8% | 51% | 4.6–9.9°C |
| December | 0% | 36% | 8% | 49% | -0.1–6.3°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