September
September · August · June
United States · 1991–2020
September leads for comfortable weather in Oakland: typically 25.1°C by day, 11.4°C at night, with 85 mm of rain. Based on measured 1991–2020 NOAA station history.
September · August · June
July · August · June
October · September · May
The weakest month is January, scoring 5 against September’s 80 — days reach only -1.2°C, 25° 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 | -1.2°C | -11.7°C | 21 mm | 3.6 | 9 h 30 | 5 | Strong coverage |
| February | 1.5°C | -9.3°C | 26 mm | 4.5 | 10 h 33 | 5 | Strong coverage |
| March | 9.5°C | -3.2°C | 49 mm | 5.4 | 11 h 48 | 15 | Strong coverage |
| April | 16.5°C | 2.8°C | 97 mm | 8.4 | 13 h 15 | 40 | Strong coverage |
| May | 22.2°C | 9.7°C | 139 mm | 11 | 14 h 28 | 63 | Strong coverage |
| June | 27.6°C | 15.6°C | 140 mm | 9.5 | 15 h 08 | 67 | Strong coverage |
| July | 29.4°C | 17.7°C | 88 mm | 6.9 | 14 h 53 | 67 | Strong coverage |
| August | 28.4°C | 16.3°C | 114 mm | 6.7 | 13 h 50 | 69 | Strong coverage |
| September | 25.1°C | 11.4°C | 85 mm | 6.5 | 12 h 25 | 80 | Strong coverage |
| October | 17.5°C | 4.5°C | 74 mm | 6.6 | 11 h 01 | 51 | Strong coverage |
| November | 8.8°C | -2.6°C | 41 mm | 4.2 | 9 h 48 | 16 | Strong coverage |
| December | 1.7°C | -8.3°C | 33 mm | 4.1 | 9 h 12 | 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 | 20.6°C25 Jan 1944 | -35.0°C12 Jan 1974 | 40 mm27 Jan 1949 | 95 mm1949 · driest 0 mm in 1987 | 103 |
| February | 25.6°C27 Feb 2024 | -33.9°C3 Feb 1996 | 58 mm19 Feb 1954 | 81 mm1954 · driest 0 mm in 1923 | 104 |
| March | 33.3°C22 Mar 2026 | -31.7°C11 Mar 1948 | 52 mm5 Mar 1946 | 151 mm1946 · driest 1 mm in 1988 | 104 |
| April | 33.9°C12 Apr 1996 | -17.8°C3 Apr 1975 | 84 mm25 Apr 2007 | 247 mm1986 · driest 0 mm in 1934 | 103 |
| May | 40.0°C30 May 1934 | -6.1°C2 May 1961 | 93 mm6 May 2007 | 226 mm2007 · driest 6 mm in 1934 | 104 |
| June | 42.2°C24 Jun 1937 | 0.6°C4 Jun 1951 | 114 mm4 Jun 2014 | 372 mm1967 · driest 8 mm in 1933 | 103 |
| July | 46.7°C25 Jul 1936 | 2.2°C30 Jul 1971 | 102 mm9 Jul 1955 | 271 mm1958 · driest 3 mm in 2014 | 103 |
| August | 42.8°C5 Aug 1934 | 1.7°C20 Aug 1950 | 182 mm12 Aug 1932 | 355 mm1932 · driest 2 mm in 2003 | 103 |
| September | 39.4°C7 Sep 1939 | -5.6°C28 Sep 1942 | 120 mm10 Sep 2014 | 269 mm1936 · driest 3 mm in 2024 | 102 |
| October | 34.4°C6 Oct 2024 | -18.9°C30 Oct 1925 | 104 mm1 Oct 2014 | 203 mm2007 · driest 0 mm in 1952 | 103 |
| November | 28.3°C14 Nov 1999 | -27.2°C30 Nov 1964 | 75 mm23 Nov 1931 | 183 mm1931 · driest 0 mm in 1989 | 101 |
| December | 21.7°C16 Dec 2021 | -34.4°C24 Dec 1983 | 55 mm28 Dec 1982 | 159 mm2015 · driest 0 mm in 1923 | 103 |
| Month | Days 25°C+ | Days 30°C+ | Frost nights | Heavy rain (10 mm+) | Snow days |
|---|---|---|---|---|---|
| January | 0 | 0 | 30 | <1 | 4 |
| February | 0 | 0 | 26 | <1 | 4 |
| March | 1 | 0 | 22 | 1 | 2 |
| April | 4 | <1 | 9 | 3 | <1 |
| May | 11 | 3 | <1 | 5 | 0 |
| June | 23 | 10 | 0 | 4 | 0 |
| July | 28 | 15 | 0 | 3 | 0 |
| August | 26 | 11 | 0 | 3 | 0 |
| September | 17 | 5 | <1 | 3 | 0 |
| October | 5 | <1 | 7 | 2 | <1 |
| November | <1 | 0 | 21 | 1 | 1 |
| 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% | 2% | 5% | -4.5–4.3°C |
| February | <1% | 13% | 2% | 10% | -2.8–7.2°C |
| March | 9% | 18% | 5% | 15% | 4.9–13.1°C |
| April | 30% | 25% | 9% | 30% | 14.1–20.0°C |
| May | 53% | 30% | 12% | 35% | 20.9–25.9°C |
| June | 69% | 30% | 13% | 34% | 25.9–30.7°C |
| July | 78% | 22% | 9% | 20% | 28.4–33.3°C |
| August | 75% | 24% | 11% | 25% | 27.2–31.5°C |
| September | 70% | 22% | 9% | 22% | 22.8–27.8°C |
| October | 41% | 18% | 6% | 16% | 15.8–22.0°C |
| November | 7% | 13% | 4% | 8% | 5.5–12.6°C |
| December | <1% | 12% | 2% | 7% | -1.9–5.8°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