September is one of the warmer months of the year in Florence, with average highs near 29.3°C and lows around 16.7°C (mean 23°C). It is one of the drier months, averaging 97 mm of rainfall and 68% relative humidity across the period.
September is one of the warmer months of the year in Florence. Across 45 years of records, the warmest September in Florence was 2019 — when the month averaged 27.5°C — while the coldest was 1989 at 20.6°C. Typical September days reach 29.3°C with nights near 16.7°C. The long-term trend is warming, about 0.3°C per decade.
September is one of the drier months in Florence, averaging 97 mm of rainfall. The wettest September on record was 2009 with 247 mm, while the driest was 2019 at 12 mm.
Relative humidity in Florence during September averages 68%. The most humid September was 1989 at 84%, and the least humid was 1999 at 41%.
September receives about 4.8 kWh/m²/day of solar energy in Florence. The sunniest Septembers were 2016 and 2019 at 5.6 kWh/m²/day, and the cloudiest was 2009 at 3.9.
Average wind speed in Florence during September is 1.2 m/s. The windiest Septembers were 1984, 2000 and 2008 at 1.5 m/s, while the calmest were 2009, 2019 and 2025 at 1 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 22.4°C | 22.9°C | 22.8°C | 23.8°C | 23.0°C | +0.6°C |
| Avg High | 28.7°C | 29.5°C | 28.8°C | 30.2°C | 29.2°C | +0.5°C |
| Avg Low | 16.1°C | 16.3°C | 16.7°C | 17.5°C | 16.9°C | +0.8°C |
| Avg Rain | 97 mm | 89 mm | 115 mm | 79 mm | 107 mm | +10 mm |
September temperatures in Florence have risen by about 1.2°C between 1981–1985 and 2021–2025.
September has ranged from a record low of 4.1°C (2001) to a record high of 39.8°C (1990).
Rainfall in September is one of the drier months, averaging 97 mm, with a wettest year of 247 mm.
One of the best times to visit Florence
September is one of the best times to visit Florence. Expect days averaging 29.3°C and nights around 16.7°C (mean 23°C) — warmer than Florence's yearly average — with higher rainfall (97 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 | 31.0°C | 24.2°C | 17.4°C | 34.6°C | 10.4°C | 116 mm | 65% | 1 m/s | 5.1 |
| 2024 | 29.0°C | 23.4°C | 17.8°C | 34.7°C | 10.4°C | 189 mm | 70% | 1.4 m/s | 4.2 |
| 2023 | 31.4°C | 24.4°C | 17.4°C | 33.9°C | 12.7°C | 23 mm | 62% | 1.1 m/s | 5.1 |
| 2022 | 29.8°C | 22.9°C | 16.1°C | 37.6°C | 7.1°C | 69 mm | 65% | 1.2 m/s | 5.2 |
| 2021 | 27.0°C | 21.7°C | 16.4°C | 30.3°C | 8.8°C | 123 mm | 80% | 1.1 m/s | 4.9 |
| 2020 | 26.8°C | 21.5°C | 16.2°C | 31.8°C | 8.2°C | 124 mm | 80% | 1.3 m/s | 4.4 |
| 2019 🔥 | 34.5°C | 27.5°C | 20.6°C | 37.4°C | 16.4°C | 12 mm | 60% | 1 m/s | 5.6 |
| 2018 | 31.8°C | 26.1°C | 20.4°C | 37.0°C | 15.3°C | 130 mm | 71% | 1.2 m/s | 4.5 |
| 2017 | 27.5°C | 21.7°C | 15.9°C | 31.9°C | 9.4°C | 72 mm | 74% | 1.2 m/s | 5.1 |
| 2016 | 32.4°C | 25.6°C | 18.8°C | 35.9°C | 9.9°C | 29 mm | 63% | 1.2 m/s | 5.6 |
| 2015 | 29.8°C | 23.4°C | 16.9°C | 34.1°C | 9.5°C | 39 mm | 68% | 1.1 m/s | 4.9 |
| 2014 | 30.0°C | 23.8°C | 17.5°C | 33.5°C | 9.2°C | 25 mm | 70% | 1.1 m/s | 5 |
| 2013 | 29.3°C | 23.1°C | 16.9°C | 34.7°C | 10.1°C | 107 mm | 72% | 1.1 m/s | 5.2 |
| 2012 | 28.1°C | 22.0°C | 15.8°C | 34.1°C | 5.9°C | 156 mm | 72% | 1.2 m/s | 4.8 |
| 2011 | 26.2°C | 20.8°C | 15.3°C | 38.2°C | 10.1°C | 177 mm | 73% | 1.4 m/s | 4.4 |
| 2010 | 31.9°C | 24.5°C | 17.0°C | 36.4°C | 9.8°C | 47 mm | 59% | 1.2 m/s | 5.3 |
| 2009 🌧️ | 27.1°C | 22.6°C | 18.2°C | 31.0°C | 7.8°C | 247 mm | 82% | 1 m/s | 3.9 |
| 2008 | 29.7°C | 23.4°C | 17.1°C | 33.9°C | 11.2°C | 31 mm | 67% | 1.5 m/s | 4.5 |
| 2007 | 30.7°C | 24.4°C | 18.0°C | 34.4°C | 9.7°C | 67 mm | 65% | 1.2 m/s | 4.9 |
| 2006 | 28.7°C | 21.9°C | 15.2°C | 33.0°C | 6.7°C | 83 mm | 65% | 1.4 m/s | 5 |
| 2005 | 30.1°C | 23.8°C | 17.5°C | 33.7°C | 6.6°C | 99 mm | 69% | 1.2 m/s | 5.3 |
| 2004 | 26.9°C | 21.3°C | 15.6°C | 31.3°C | 8.2°C | 110 mm | 78% | 1.4 m/s | 5.2 |
| 2003 | 27.9°C | 21.6°C | 15.4°C | 32.6°C | 5.2°C | 147 mm | 72% | 1.3 m/s | 5.4 |
| 2002 | 30.9°C | 24.9°C | 18.9°C | 37.1°C | 12.0°C | 185 mm | 67% | 1.3 m/s | 4.3 |
| 2001 | 26.6°C | 20.8°C | 14.9°C | 31.1°C | 4.1°C | 109 mm | 72% | 1.3 m/s | 4.9 |
| 2000 | 29.7°C | 23.1°C | 16.4°C | 36.3°C | 6.3°C | 72 mm | 61% | 1.5 m/s | 4.6 |
| 1999 | 31.7°C | 23.8°C | 15.9°C | 38.9°C | 7.0°C | 22 mm | 41% | 1.3 m/s | 5.2 |
| 1998 | 33.4°C | 26.1°C | 18.9°C | 38.0°C | 11.1°C | 35 mm | 55% | 1.2 m/s | 5.2 |
| 1997 | 29.6°C | 22.9°C | 16.1°C | 35.1°C | 9.8°C | 108 mm | 66% | 1.1 m/s | 5.2 |
| 1996 | 27.8°C | 21.6°C | 15.4°C | 32.5°C | 6.9°C | 144 mm | 72% | 1.3 m/s | 4.7 |
| 1995 | 29.1°C | 22.4°C | 15.7°C | 34.5°C | 6.8°C | 90 mm | 66% | 1.2 m/s | 4.7 |
| 1994 | 28.5°C | 21.5°C | 14.6°C | 32.3°C | 9.1°C | 68 mm | 68% | 1.1 m/s | 4.9 |
| 1993 | 28.6°C | 22.0°C | 15.4°C | 36.3°C | 5.5°C | 145 mm | 68% | 1.3 m/s | 4.7 |
| 1992 | 26.2°C | 21.0°C | 15.7°C | 31.1°C | 4.8°C | 141 mm | 81% | 1.3 m/s | 4.2 |
| 1991 | 28.7°C | 22.9°C | 17.1°C | 34.6°C | 4.9°C | 77 mm | 69% | 1.1 m/s | 5.1 |
| 1990 | 31.8°C | 25.2°C | 18.6°C | 39.8°C | 5.7°C | 59 mm | 58% | 1.1 m/s | 5 |
| 1989 ❄️ | 25.5°C | 20.6°C | 15.7°C | 31.1°C | 5.4°C | 220 mm | 84% | 1.2 m/s | 4 |
| 1988 | 29.0°C | 23.3°C | 17.6°C | 34.6°C | 8.9°C | 170 mm | 74% | 1.4 m/s | 4 |
| 1987 | 29.2°C | 22.8°C | 16.4°C | 34.3°C | 10.9°C | 118 mm | 63% | 1.2 m/s | 4.8 |
| 1986 | 29.7°C | 24.1°C | 18.4°C | 33.3°C | 12.7°C | 106 mm | 74% | 1.2 m/s | 4.5 |
| 1985 | 28.1°C | 21.6°C | 15.1°C | 32.8°C | 6.6°C | 92 mm | 67% | 1.4 m/s | 5.1 |
| 1984 | 30.1°C | 22.6°C | 15.1°C | 36.7°C | 7.3°C | 13 mm | 54% | 1.5 m/s | 5 |
| 1983 | 29.3°C | 23.0°C | 16.6°C | 35.7°C | 5.2°C | 61 mm | 63% | 1.2 m/s | — |
| 1982 | 28.6°C | 22.1°C | 15.5°C | 32.8°C | 6.7°C | 47 mm | 68% | 1.2 m/s | — |
| 1981 | 28.5°C | 21.4°C | 14.3°C | 32.2°C | 6.7°C | 49 mm | 65% | 1.1 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 29.3°C with lows near 16.7°C (mean 23°C), based on 45 years of NASA POWER data.
September averages 97 mm of rainfall in Florence, one of the drier months. The wettest on record was 247 mm in 2009.
The hottest September reached 39.8°C in 1990. The coldest dipped to 4.1°C in 2001.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 1.2°C. Daytime highs moved from 28.9°C to 29.6°C and overnight lows from 15.3°C to 17°C over the same span.
September is one of the warmer months of the year in Florence and one of the drier months, so plan for around 29.3°C daytime highs and 16.7°C at night.
Not quite — September is the 9th coolest month in Florence, averaging 23°C.
For September in Florence, pack light layers you can adjust through the day, with typical highs of 29.3°C and lows of 16.7°C. Bring an umbrella or light rain jacket too.
Relative humidity in September averages 68% — moderately humid.
Average wind speed in September is 1.2 m/s. The windiest September on record averaged 1.5 m/s (1984).
The wettest September on record was 2009 with 247 mm. On average, September sees 97 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 Florence 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.
