August is one of the warmer months of the year in New Castle, with average highs near 29°C and lows around 15.6°C (mean 22.3°C). It is about average for rainfall, averaging 82 mm of rainfall and 68% relative humidity across the period.
August is one of the warmer months of the year in New Castle. Across 45 years of records, the warmest August in New Castle was 2016 — when the month averaged 25°C — while the coldest was 1992 at 19.2°C. Typical August days reach 29°C with nights near 15.6°C. The long-term trend is warming, about 0.3°C per decade.
August is about average for rainfall in New Castle, averaging 82 mm of rainfall. The wettest August on record was 2007 with 162 mm, while the driest was 2025 at 21 mm.
Relative humidity in New Castle during August averages 68%. The most humid August was 1990 at 77%, and the least humid was 2025 at 59%.
August receives about 5.1 kWh/m²/day of solar energy in New Castle. The sunniest August was 2025 at 5.7 kWh/m²/day, and the cloudiest were 1984, 1987 and 1997 at 4.4.
Average wind speed in New Castle during August is 0.1 m/s. The windiest Augusts were 2023, 2024 and 2025, among others at 0.1 m/s, while the calmest were 2000, 2001 and 2018, among others at 0 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 21.7°C | 21.8°C | 22.4°C | 22.7°C | 23.0°C | +1.3°C |
| Avg High | 28.6°C | 28.6°C | 28.9°C | 29.3°C | 29.8°C | +1.2°C |
| Avg Low | 14.8°C | 15.2°C | 15.8°C | 16.0°C | 16.3°C | +1.5°C |
| Avg Rain | 82 mm | 81 mm | 93 mm | 68 mm | 85 mm | +4 mm |
August temperatures in New Castle have risen by about 1.3°C between 1981–1985 and 2021–2025.
August has ranged from a record low of 3.4°C (1982) to a record high of 37.5°C (2002).
Rainfall in August is about average for rainfall, averaging 82 mm, with a wettest year of 162 mm.
One of the best times to visit New Castle
August is one of the best times to visit New Castle. Expect days averaging 29°C and nights around 15.6°C (mean 22.3°C) — warmer than New Castle's yearly average — with higher rainfall (82 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 | 29.7°C | 22.2°C | 14.8°C | 35.7°C | 8.0°C | 21 mm | 59% | 0.1 m/s | 5.7 |
| 2024 | 30.4°C | 23.4°C | 16.4°C | 36.0°C | 9.0°C | 78 mm | 66% | 0.1 m/s | 5.1 |
| 2023 | 28.2°C | 21.7°C | 15.2°C | 32.4°C | 9.9°C | 128 mm | 72% | 0.1 m/s | 5.1 |
| 2022 | 30.0°C | 23.3°C | 16.7°C | 35.0°C | 11.2°C | 65 mm | 68% | 0.1 m/s | 5.4 |
| 2021 | 30.3°C | 24.1°C | 18.0°C | 34.4°C | 11.8°C | 125 mm | 72% | 0.1 m/s | 5.2 |
| 2020 | 30.0°C | 23.3°C | 16.6°C | 34.6°C | 10.6°C | 97 mm | 65% | 0.1 m/s | 5.4 |
| 2019 | 28.2°C | 22.3°C | 16.3°C | 32.1°C | 11.8°C | 62 mm | 73% | 0.1 m/s | 5.4 |
| 2018 | 30.4°C | 24.1°C | 17.8°C | 35.2°C | 11.0°C | 55 mm | 70% | 0 m/s | 5 |
| 2017 | 28.3°C | 21.7°C | 15.1°C | 32.0°C | 10.9°C | 42 mm | 67% | 0.1 m/s | 5.1 |
| 2016 🔥 | 31.5°C | 25.0°C | 18.5°C | 35.2°C | 12.4°C | 70 mm | 67% | 0.1 m/s | 5.5 |
| 2015 | 29.0°C | 21.9°C | 14.8°C | 33.9°C | 10.6°C | 38 mm | 65% | 0.1 m/s | 5.5 |
| 2014 | 27.6°C | 21.1°C | 14.7°C | 31.7°C | 8.4°C | 117 mm | 72% | 0.1 m/s | 5.3 |
| 2013 | 28.0°C | 21.5°C | 15.0°C | 32.6°C | 9.6°C | 60 mm | 70% | 0.1 m/s | 5.1 |
| 2012 | 29.5°C | 22.2°C | 14.9°C | 35.4°C | 9.8°C | 86 mm | 65% | 0.1 m/s | 5.5 |
| 2011 | 29.2°C | 22.6°C | 16.0°C | 33.8°C | 10.3°C | 92 mm | 67% | 0.1 m/s | 5.4 |
| 2010 | 31.1°C | 24.2°C | 17.3°C | 35.4°C | 10.2°C | 61 mm | 64% | 0.1 m/s | 5.3 |
| 2009 | 28.2°C | 22.1°C | 16.1°C | 34.0°C | 9.7°C | 79 mm | 71% | 0.1 m/s | 5 |
| 2008 | 27.8°C | 21.0°C | 14.2°C | 33.0°C | 9.2°C | 57 mm | 67% | 0.1 m/s | 5.6 |
| 2007 🌧️ | 29.0°C | 23.1°C | 17.2°C | 35.3°C | 10.4°C | 162 mm | 73% | 0.1 m/s | 4.7 |
| 2006 | 29.2°C | 22.7°C | 16.2°C | 33.6°C | 9.0°C | 67 mm | 68% | 0.1 m/s | 5.1 |
| 2005 | 30.4°C | 23.7°C | 17.0°C | 35.0°C | 11.0°C | 108 mm | 65% | 0.1 m/s | 5 |
| 2004 | 25.9°C | 20.1°C | 14.3°C | 32.8°C | 7.7°C | 126 mm | 76% | 0.1 m/s | 4.7 |
| 2003 | 28.8°C | 22.6°C | 16.4°C | 34.5°C | 10.7°C | 100 mm | 75% | 0.1 m/s | 5 |
| 2002 | 31.1°C | 23.6°C | 16.1°C | 37.5°C | 10.4°C | 60 mm | 61% | 0.1 m/s | 5.5 |
| 2001 | 30.8°C | 23.7°C | 16.5°C | 37.4°C | 11.2°C | 94 mm | 63% | 0 m/s | 4.9 |
| 2000 | 28.0°C | 21.2°C | 14.4°C | 31.8°C | 7.5°C | 74 mm | 70% | 0 m/s | 5 |
| 1999 | 28.0°C | 21.1°C | 14.2°C | 32.9°C | 9.4°C | 54 mm | 65% | 0 m/s | 4.9 |
| 1998 | 30.9°C | 23.6°C | 16.4°C | 35.0°C | 8.3°C | 76 mm | 63% | 0.1 m/s | 5.3 |
| 1997 | 27.0°C | 20.8°C | 14.6°C | 32.4°C | 9.6°C | 110 mm | 70% | 0.1 m/s | 4.4 |
| 1996 | 28.3°C | 21.6°C | 15.0°C | 34.0°C | 11.5°C | 63 mm | 70% | 0.1 m/s | 5.3 |
| 1995 | 31.2°C | 24.4°C | 17.7°C | 36.6°C | 10.8°C | 69 mm | 68% | 0.1 m/s | 5.2 |
| 1994 | 26.8°C | 20.4°C | 14.0°C | 31.9°C | 6.8°C | 144 mm | 73% | 0.1 m/s | 4.7 |
| 1993 | 30.9°C | 23.4°C | 16.0°C | 36.1°C | 9.4°C | 48 mm | 61% | 0.1 m/s | 5.1 |
| 1992 ❄️ | 25.5°C | 19.2°C | 13.0°C | 30.9°C | 7.7°C | 113 mm | 76% | 0.1 m/s | 5 |
| 1991 | 30.5°C | 23.2°C | 15.9°C | 36.0°C | 10.9°C | 48 mm | 61% | 0.1 m/s | 5.1 |
| 1990 | 26.5°C | 20.7°C | 14.9°C | 30.4°C | 9.7°C | 85 mm | 77% | 0.1 m/s | 4.6 |
| 1989 | 27.9°C | 21.5°C | 15.1°C | 31.9°C | 8.5°C | 40 mm | 70% | 0.1 m/s | 4.9 |
| 1988 | 30.6°C | 23.5°C | 16.4°C | 36.8°C | 7.1°C | 94 mm | 64% | 0.1 m/s | 4.8 |
| 1987 | 28.4°C | 21.7°C | 15.0°C | 34.9°C | 8.2°C | 151 mm | 69% | 0.1 m/s | 4.4 |
| 1986 | 27.3°C | 20.5°C | 13.7°C | 31.1°C | 5.6°C | 55 mm | 66% | 0.1 m/s | 4.9 |
| 1985 | 28.0°C | 21.1°C | 14.2°C | 33.3°C | 9.3°C | 84 mm | 67% | 0.1 m/s | 4.6 |
| 1984 | 28.4°C | 22.0°C | 15.6°C | 32.6°C | 8.3°C | 119 mm | 73% | 0.1 m/s | 4.4 |
| 1983 | 30.9°C | 23.5°C | 16.1°C | 35.3°C | 9.3°C | 75 mm | 66% | 0.1 m/s | — |
| 1982 | 27.8°C | 20.6°C | 13.3°C | 35.0°C | 3.4°C | 57 mm | 63% | 0.1 m/s | — |
| 1981 | 27.9°C | 21.0°C | 14.1°C | 31.3°C | 6.6°C | 63 mm | 68% | 0.1 m/s | — |
Actual recorded August data for each year, 1981–2025 — sourced from NASA POWER.
The average high in August is around 29°C with lows near 15.6°C (mean 22.3°C), based on 45 years of NASA POWER data.
August averages 82 mm of rainfall in New Castle, about average for rainfall. The wettest on record was 162 mm in 2007.
The hottest August reached 37.5°C in 2002. The coldest dipped to 3.4°C in 1982.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average August temperatures have risen by about 1.3°C. Daytime highs moved from 28.6°C to 29.7°C and overnight lows from 14.7°C to 16.2°C over the same span.
August is one of the warmer months of the year in New Castle and about average for rainfall, so plan for around 29°C daytime highs and 15.6°C at night.
Not quite — August is the 11th coolest month in New Castle, averaging 22.3°C.
For August in New Castle, pack light layers you can adjust through the day, with typical highs of 29°C and lows of 15.6°C. Bring an umbrella or light rain jacket too.
Relative humidity in August averages 68% — moderately humid.
Average wind speed in August is 0.1 m/s. The windiest August on record averaged 0.1 m/s (1981).
The wettest August on record was 2007 with 162 mm. On average, August sees 82 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 New Castle behaves each August, 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 August specifically, along with year-by-year records and how the month has changed over the decades.
