September is one of the warmer months of the year in Erie, with average highs near 21.8°C and lows around 13.2°C (mean 17.5°C). It is a relatively wet time of year, averaging 95 mm of rainfall and 74% relative humidity across the period.
September is one of the warmer months of the year in Erie. Across 45 years of records, the warmest September in Erie was 2015 — when the month averaged 20.4°C — while the coldest was 1993 at 14.6°C. Typical September days reach 21.8°C with nights near 13.2°C. The long-term trend is warming, about 0.9°C per decade.
September is a relatively wet time of year in Erie, averaging 95 mm of rainfall. The wettest September on record was 1996 with 195 mm, while the driest was 2023 at 28 mm.
Relative humidity in Erie during September averages 74%. The most humid September was 1987 at 84%, and the least humid was 2025 at 66%.
September receives about 4.2 kWh/m²/day of solar energy in Erie. The sunniest September was 2025 at 4.9 kWh/m²/day, and the cloudiest was 1993 at 3.3.
Average wind speed in Erie during September is 1.3 m/s. The windiest Septembers were 2010 and 2021 at 1.6 m/s, while the calmest was 1987 at 1 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 16.5°C | 16.1°C | 17.7°C | 18.7°C | 19.0°C | +2.5°C |
| Avg High | 20.7°C | 20.3°C | 22.0°C | 23.0°C | 23.4°C | +2.7°C |
| Avg Low | 12.3°C | 11.8°C | 13.4°C | 14.4°C | 14.6°C | +2.3°C |
| Avg Rain | 106 mm | 105 mm | 99 mm | 92 mm | 61 mm | -45 mm |
September temperatures in Erie have risen by about 2.3°C between 1981–1985 and 2021–2025.
September has ranged from a record low of 2.5°C (1989) to a record high of 31.9°C (2002).
Rainfall in September is a relatively wet time of year, averaging 95 mm, with a wettest year of 195 mm.
One of the best times to visit Erie
September is one of the best times to visit Erie. Expect days averaging 21.8°C and nights around 13.2°C (mean 17.5°C) — warmer than Erie's yearly average — with higher rainfall (95 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 | 24.4°C | 19.3°C | 14.2°C | 28.5°C | 10.1°C | 43 mm | 66% | 1.1 m/s | 4.9 |
| 2024 | 24.6°C | 20.0°C | 15.5°C | 28.9°C | 11.4°C | 73 mm | 70% | 1.2 m/s | 4.4 |
| 2023 | 23.3°C | 18.9°C | 14.6°C | 30.8°C | 10.3°C | 28 mm | 72% | 1.2 m/s | 4.3 |
| 2022 | 22.0°C | 18.2°C | 14.5°C | 28.4°C | 5.9°C | 118 mm | 74% | 1.4 m/s | 4.1 |
| 2021 | 23.3°C | 19.1°C | 14.9°C | 27.8°C | 10.0°C | 65 mm | 71% | 1.6 m/s | 4.6 |
| 2020 | 23.0°C | 18.4°C | 13.8°C | 29.9°C | 7.2°C | 39 mm | 70% | 1.5 m/s | 4.4 |
| 2019 | 23.4°C | 19.2°C | 15.0°C | 27.5°C | 11.5°C | 90 mm | 77% | 1.4 m/s | 4.3 |
| 2018 | 24.1°C | 20.2°C | 16.2°C | 31.6°C | 9.5°C | 118 mm | 79% | 1.3 m/s | 3.9 |
| 2017 | 23.3°C | 18.9°C | 14.4°C | 30.7°C | 8.0°C | 67 mm | 73% | 1.2 m/s | 4.6 |
| 2016 | 25.1°C | 20.3°C | 15.5°C | 29.8°C | 9.3°C | 94 mm | 70% | 1.4 m/s | 4.6 |
| 2015 🔥 | 25.0°C | 20.4°C | 15.8°C | 30.8°C | 10.9°C | 92 mm | 71% | 1.3 m/s | 4.4 |
| 2014 | 22.2°C | 17.6°C | 13.1°C | 29.0°C | 8.8°C | 69 mm | 75% | 1.3 m/s | 4.4 |
| 2013 | 21.3°C | 16.9°C | 12.5°C | 29.4°C | 7.1°C | 69 mm | 74% | 1.4 m/s | 4.1 |
| 2012 | 21.6°C | 17.5°C | 13.4°C | 31.4°C | 8.2°C | 107 mm | 71% | 1.4 m/s | 4.3 |
| 2011 | 21.9°C | 18.3°C | 14.7°C | 31.1°C | 8.4°C | 131 mm | 81% | 1.4 m/s | 3.7 |
| 2010 | 21.6°C | 17.6°C | 13.7°C | 30.3°C | 9.9°C | 87 mm | 71% | 1.6 m/s | 3.7 |
| 2009 | 21.9°C | 17.9°C | 13.8°C | 26.4°C | 7.3°C | 69 mm | 74% | 1.4 m/s | 4.3 |
| 2008 | 23.1°C | 18.6°C | 14.0°C | 31.3°C | 9.9°C | 59 mm | 72% | 1.3 m/s | 4.3 |
| 2007 | 23.6°C | 19.0°C | 14.3°C | 30.7°C | 8.5°C | 73 mm | 70% | 1.3 m/s | 4.6 |
| 2006 | 19.2°C | 16.0°C | 12.8°C | 25.4°C | 7.1°C | 134 mm | 82% | 1.5 m/s | 3.6 |
| 2005 | 23.9°C | 19.3°C | 14.6°C | 28.4°C | 8.0°C | 92 mm | 71% | 1.4 m/s | 4.7 |
| 2004 | 22.7°C | 18.6°C | 14.5°C | 27.9°C | 8.6°C | 141 mm | 78% | 1.3 m/s | 4.7 |
| 2003 | 20.0°C | 16.0°C | 12.1°C | 24.9°C | 6.0°C | 147 mm | 80% | 1.3 m/s | 4.2 |
| 2002 | 24.0°C | 18.9°C | 13.8°C | 31.9°C | 8.5°C | 122 mm | 68% | 1.1 m/s | 4.7 |
| 2001 | 20.1°C | 15.6°C | 11.0°C | 29.1°C | 5.4°C | 72 mm | 71% | 1.2 m/s | 4.5 |
| 2000 | 21.8°C | 17.2°C | 12.6°C | 29.9°C | 3.2°C | 85 mm | 71% | 1.5 m/s | 4.1 |
| 1999 | 22.6°C | 17.9°C | 13.2°C | 30.4°C | 5.3°C | 94 mm | 67% | 1.3 m/s | 4.5 |
| 1998 | 23.2°C | 18.9°C | 14.6°C | 29.3°C | 8.3°C | 46 mm | 68% | 1.4 m/s | 4.4 |
| 1997 | 20.6°C | 16.5°C | 12.4°C | 26.1°C | 6.4°C | 92 mm | 75% | 1.5 m/s | 4.2 |
| 1996 🌧️ | 19.4°C | 15.9°C | 12.3°C | 27.0°C | 7.1°C | 195 mm | 83% | 1.3 m/s | 3.5 |
| 1995 | 20.0°C | 15.2°C | 10.4°C | 27.6°C | 3.5°C | 41 mm | 69% | 1.2 m/s | 4.4 |
| 1994 | 19.6°C | 15.4°C | 11.3°C | 25.9°C | 7.9°C | 77 mm | 76% | 1.2 m/s | 4.2 |
| 1993 ❄️ | 18.5°C | 14.6°C | 10.6°C | 27.2°C | 2.9°C | 121 mm | 77% | 1.3 m/s | 3.3 |
| 1992 | 19.5°C | 15.1°C | 10.8°C | 25.3°C | 2.6°C | 134 mm | 81% | 1.2 m/s | 4.1 |
| 1991 | 20.5°C | 15.9°C | 11.3°C | 28.0°C | 4.6°C | 62 mm | 67% | 1.2 m/s | 4.2 |
| 1990 | 19.2°C | 15.3°C | 11.4°C | 25.8°C | 5.1°C | 189 mm | 82% | 1.2 m/s | 3.7 |
| 1989 | 20.2°C | 16.0°C | 11.7°C | 26.9°C | 2.5°C | 104 mm | 78% | 1.2 m/s | 4 |
| 1988 | 20.4°C | 15.7°C | 11.0°C | 25.4°C | 6.3°C | 91 mm | 75% | 1.3 m/s | 4.5 |
| 1987 | 19.3°C | 15.6°C | 12.0°C | 25.0°C | 6.0°C | 134 mm | 84% | 1 m/s | 3.7 |
| 1986 | 21.5°C | 17.3°C | 13.2°C | 25.8°C | 5.0°C | 141 mm | 78% | 1.3 m/s | 3.9 |
| 1985 | 22.8°C | 18.3°C | 13.7°C | 28.5°C | 7.9°C | 59 mm | 69% | 1.3 m/s | 4.5 |
| 1984 | 19.8°C | 15.7°C | 11.5°C | 26.8°C | 4.8°C | 113 mm | 76% | 1.4 m/s | 4.3 |
| 1983 | 22.3°C | 17.9°C | 13.5°C | 28.9°C | 5.9°C | 100 mm | 70% | 1.5 m/s | — |
| 1982 | 21.1°C | 16.6°C | 12.2°C | 29.8°C | 8.0°C | 97 mm | 74% | 1.2 m/s | — |
| 1981 | 19.2°C | 15.7°C | 12.3°C | 26.0°C | 5.7°C | 118 mm | 80% | 1.5 m/s | — |
Actual recorded September data for each year, 1981–2025 — sourced from NASA POWER.
The average high in September is around 21.8°C with lows near 13.2°C (mean 17.5°C), based on 45 years of NASA POWER data.
September averages 95 mm of rainfall in Erie, a relatively wet time of year. The wettest on record was 195 mm in 1996.
The hottest September reached 31.9°C in 2002. The coldest dipped to 2.5°C in 1989.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average September temperatures have risen by about 2.3°C. Daytime highs moved from 21°C to 23.5°C and overnight lows from 12.6°C to 14.7°C over the same span.
September is one of the warmer months of the year in Erie and a relatively wet time of year, so plan for around 21.8°C daytime highs and 13.2°C at night.
Not quite — September is the 9th coolest month in Erie, averaging 17.5°C.
For September in Erie, pack light layers you can adjust through the day, with typical highs of 21.8°C and lows of 13.2°C. Bring an umbrella or light rain jacket too.
Relative humidity in September averages 74% — moderately humid.
Average wind speed in September is 1.3 m/s. The windiest September on record averaged 1.6 m/s (2010).
The wettest September on record was 1996 with 195 mm. On average, September sees 95 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 Erie 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.
