September is one of the warmer months of the year in Redding, with average highs near 32°C and lows around 14.7°C (mean 23.4°C). It is one of the drier months, averaging 21 mm of rainfall and 33% relative humidity across the period.
September is one of the warmer months of the year in Redding. Across 45 years of records, the warmest September in Redding was 2011 — when the month averaged 26.3°C — while the coldest was 1985 at 18.3°C. Typical September days reach 32°C with nights near 14.7°C. The long-term trend is warming, about 0.6°C per decade.
September is one of the drier months in Redding, averaging 21 mm of rainfall. The wettest September on record was 1986 with 107 mm, while the driest were 2012 and 2020 at 0 mm.
Relative humidity in Redding during September averages 33%. The most humid September was 1985 at 51%, and the least humid was 2012 at 21%.
September receives about 5.7 kWh/m²/day of solar energy in Redding. The sunniest Septembers were 2002, 2004 and 2012, among others at 6.1 kWh/m²/day, and the cloudiest was 1986 at 4.9.
Average wind speed in Redding during September is 0.8 m/s. The windiest Septembers were 2003, 2004 and 2014, among others at 0.9 m/s, while the calmest were 1985 and 1987 at 0.7 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 21.7°C | 23.4°C | 23.6°C | 24.0°C | 24.5°C | +2.8°C |
| Avg High | 30.2°C | 32.2°C | 32.4°C | 32.6°C | 32.9°C | +2.7°C |
| Avg Low | 13.2°C | 14.6°C | 14.8°C | 15.4°C | 16.2°C | +3°C |
| Avg Rain | 46 mm | 11 mm | 10 mm | 17 mm | 25 mm | -21 mm |
September temperatures in Redding have risen by about 2.7°C between 1981–1985 and 2021–2025.
September has ranged from a record low of 4.4°C (1986) to a record high of 45.3°C (2022).
Rainfall in September is one of the drier months, averaging 21 mm, with a wettest year of 107 mm.
One of the best times to visit Redding
September is one of the best times to visit Redding. Expect days averaging 32°C and nights around 14.7°C (mean 23.4°C) — warmer than Redding's yearly average — with low rainfall (21 mm), so conditions are generally comfortable for sightseeing and outdoor plans.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 31.8°C | 24.3°C | 16.7°C | 38.6°C | 11.1°C | 39 mm | 41% | 0.8 m/s | 5.1 |
| 2024 | 34.2°C | 25.2°C | 16.3°C | 39.7°C | 12.0°C | 12 mm | 30% | 0.8 m/s | 5.7 |
| 2023 | 30.4°C | 22.6°C | 14.9°C | 38.1°C | 9.5°C | 30 mm | 40% | 0.8 m/s | 5.3 |
| 2022 | 33.0°C | 24.9°C | 16.8°C | 45.3°C | 11.2°C | 40 mm | 36% | 0.8 m/s | 5.3 |
| 2021 | 33.1°C | 24.1°C | 15.1°C | 40.3°C | 7.0°C | 26 mm | 31% | 0.8 m/s | 5.5 |
| 2020 | 34.8°C | 26.1°C | 17.5°C | 44.1°C | 12.9°C | 0 mm | 25% | 0.8 m/s | 5.3 |
| 2019 | 30.6°C | 22.4°C | 14.2°C | 38.2°C | 4.6°C | 35 mm | 42% | 0.8 m/s | 5.6 |
| 2018 | 32.6°C | 23.5°C | 14.4°C | 38.7°C | 8.1°C | 2 mm | 26% | 0.8 m/s | 6 |
| 2017 | 32.4°C | 24.3°C | 16.3°C | 43.1°C | 7.6°C | 7 mm | 32% | 0.8 m/s | 5.3 |
| 2016 | 33.1°C | 24.0°C | 14.8°C | 38.8°C | 9.5°C | 1 mm | 26% | 0.8 m/s | 6 |
| 2015 | 32.5°C | 23.7°C | 15.0°C | 40.6°C | 8.7°C | 17 mm | 31% | 0.8 m/s | 5.5 |
| 2014 | 32.5°C | 24.4°C | 16.2°C | 38.8°C | 10.4°C | 49 mm | 34% | 0.9 m/s | 5.6 |
| 2013 | 30.3°C | 22.3°C | 14.3°C | 39.3°C | 6.1°C | 37 mm | 41% | 0.8 m/s | 5.6 |
| 2012 | 34.8°C | 25.8°C | 16.8°C | 37.1°C | 12.7°C | 0 mm | 21% | 0.8 m/s | 6.1 |
| 2011 🔥 | 35.2°C | 26.3°C | 17.5°C | 40.7°C | 12.3°C | 2 mm | 26% | 0.8 m/s | 5.9 |
| 2010 | 32.0°C | 23.2°C | 14.3°C | 38.8°C | 9.3°C | 17 mm | 36% | 0.8 m/s | 5.7 |
| 2009 | 34.0°C | 24.9°C | 15.8°C | 41.7°C | 6.1°C | 4 mm | 28% | 0.8 m/s | 5.9 |
| 2008 | 33.9°C | 24.8°C | 15.7°C | 41.2°C | 9.9°C | 2 mm | 23% | 0.8 m/s | 6 |
| 2007 | 29.4°C | 21.3°C | 13.2°C | 38.3°C | 5.5°C | 16 mm | 38% | 0.8 m/s | 5.5 |
| 2006 | 32.7°C | 23.7°C | 14.8°C | 39.5°C | 7.2°C | 2 mm | 25% | 0.8 m/s | 6 |
| 2005 | 30.7°C | 22.2°C | 13.7°C | 36.8°C | 8.6°C | 4 mm | 30% | 0.8 m/s | 6 |
| 2004 | 32.3°C | 23.4°C | 14.4°C | 39.3°C | 7.1°C | 3 mm | 31% | 0.9 m/s | 6.1 |
| 2003 | 34.9°C | 25.4°C | 15.9°C | 40.7°C | 9.8°C | 5 mm | 26% | 0.9 m/s | 5.8 |
| 2002 | 33.1°C | 24.1°C | 15.1°C | 40.4°C | 8.7°C | 1 mm | 25% | 0.8 m/s | 6.1 |
| 2001 | 32.8°C | 24.4°C | 16.0°C | 37.8°C | 9.7°C | 21 mm | 33% | 0.8 m/s | 5.6 |
| 2000 | 29.8°C | 21.3°C | 12.9°C | 38.4°C | 7.2°C | 46 mm | 48% | 0.8 m/s | 5.5 |
| 1999 | 34.2°C | 24.7°C | 15.2°C | 38.9°C | 9.3°C | 10 mm | 25% | 0.8 m/s | 5.9 |
| 1998 | 32.8°C | 24.5°C | 16.2°C | 44.9°C | 9.0°C | 10 mm | 36% | 0.8 m/s | 5.8 |
| 1997 | 30.6°C | 22.2°C | 13.8°C | 34.9°C | 8.2°C | 28 mm | 41% | 0.9 m/s | 5.6 |
| 1996 | 30.3°C | 21.4°C | 12.6°C | 35.3°C | 7.8°C | 26 mm | 36% | 0.8 m/s | 5.7 |
| 1995 | 32.2°C | 23.9°C | 15.5°C | 39.1°C | 9.0°C | 1 mm | 31% | 0.8 m/s | 6 |
| 1994 | 31.8°C | 23.1°C | 14.4°C | 38.9°C | 10.3°C | 9 mm | 33% | 0.8 m/s | 5.7 |
| 1993 | 32.5°C | 23.3°C | 14.1°C | 39.5°C | 8.3°C | 7 mm | 28% | 0.8 m/s | 6.1 |
| 1992 | 31.8°C | 23.0°C | 14.2°C | 36.6°C | 9.6°C | 7 mm | 30% | 0.9 m/s | 5.8 |
| 1991 | 34.8°C | 25.4°C | 15.9°C | 39.9°C | 10.5°C | 1 mm | 24% | 0.8 m/s | 6 |
| 1990 | 31.4°C | 22.8°C | 14.3°C | 37.0°C | 11.7°C | 15 mm | 34% | 0.8 m/s | 5.9 |
| 1989 | 28.8°C | 20.8°C | 12.7°C | 35.3°C | 8.4°C | 104 mm | 42% | 0.8 m/s | 5.5 |
| 1988 | 33.3°C | 24.1°C | 14.8°C | 44.5°C | 10.3°C | 0 mm | 22% | 0.8 m/s | 5.9 |
| 1987 | 34.1°C | 24.6°C | 15.1°C | 41.0°C | 10.1°C | 0 mm | 23% | 0.7 m/s | 5.8 |
| 1986 🌧️ | 25.7°C | 18.4°C | 11.1°C | 39.0°C | 4.4°C | 107 mm | 49% | 0.8 m/s | 4.9 |
| 1985 ❄️ | 26.1°C | 18.3°C | 10.5°C | 33.8°C | 6.0°C | 73 mm | 51% | 0.7 m/s | 5.2 |
| 1984 | 31.7°C | 22.5°C | 13.3°C | 39.0°C | 6.3°C | 17 mm | 33% | 0.8 m/s | 5.6 |
| 1983 | 31.3°C | 22.7°C | 14.0°C | 37.9°C | 9.1°C | 41 mm | 42% | 0.8 m/s | — |
| 1982 | 28.9°C | 20.6°C | 12.3°C | 40.0°C | 5.8°C | 34 mm | 41% | 0.8 m/s | — |
| 1981 | 32.2°C | 23.5°C | 14.8°C | 38.6°C | 7.5°C | 38 mm | 32% | 0.8 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 32°C with lows near 14.7°C (mean 23.4°C), based on 45 years of NASA POWER data.
September averages 21 mm of rainfall in Redding, one of the drier months. The wettest on record was 107 mm in 1986.
The hottest September reached 45.3°C in 2022. The coldest dipped to 4.4°C in 1986.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 2.7°C. Daytime highs moved from 30°C to 32.5°C and overnight lows from 13°C to 16°C over the same span.
September is one of the warmer months of the year in Redding and one of the drier months, so plan for around 32°C daytime highs and 14.7°C at night.
Not quite — September is the 10th coolest month in Redding, averaging 23.4°C.
For September in Redding, pack light, breathable clothing and sun protection, with typical highs of 32°C and lows of 14.7°C.
Relative humidity in September averages 33% — relatively dry.
Average wind speed in September is 0.8 m/s. The windiest September on record averaged 0.9 m/s (1992).
The wettest September on record was 1986 with 107 mm. On average, September sees 21 mm.
All figures are derived from NASA POWER (Prediction Of Worldwide Energy Resources), based on MERRA-2 satellite reanalysis, covering 1981–2025.
Explore how the weather in Redding behaves each September, based on 45 years of NASA POWER climate data from 1981 to 2025. This page breaks down average temperatures, rainfall, humidity, wind and solar radiation for September specifically, along with year-by-year records and how the month has changed over the decades.
