July is one of the warmer months of the year in New Castle, with average highs near 29.3°C and lows around 16.5°C (mean 22.9°C). It is a relatively wet time of year, averaging 94 mm of rainfall and 70% relative humidity across the period.
July is one of the warmer months of the year in New Castle. Across 45 years of records, the warmest July in New Castle was 2020 — when the month averaged 25.7°C — while the coldest was 1984 at 20°C. Typical July days reach 29.3°C with nights near 16.5°C. The long-term trend is warming, about 0.4°C per decade.
July is a relatively wet time of year in New Castle, averaging 94 mm of rainfall. The wettest July on record was 1992 with 201 mm, while the driest was 1997 at 33 mm.
Relative humidity in New Castle during July averages 70%. The most humid July was 2013 at 79%, and the least humid was 1988 at 58%.
July receives about 5.8 kWh/m²/day of solar energy in New Castle. The sunniest July was 2020 at 6.5 kWh/m²/day, and the cloudiest was 1992 at 4.6.
Average wind speed in New Castle during July is 0.1 m/s. The windiest Julys were 2023, 2024 and 2025, among others at 0.1 m/s, while the calmest were 1993, 1996 and 2012, 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 | 22.4°C | 22.6°C | 22.2°C | 23.5°C | 24.3°C | +1.9°C |
| Avg High | 28.8°C | 28.9°C | 28.5°C | 29.8°C | 30.8°C | +2°C |
| Avg Low | 16.0°C | 16.3°C | 15.9°C | 17.3°C | 17.7°C | +1.7°C |
| Avg Rain | 96 mm | 101 mm | 99 mm | 85 mm | 87 mm | -8 mm |
July temperatures in New Castle have risen by about 2.1°C between 1981–1985 and 2021–2025.
July has ranged from a record low of 7.6°C (2001) to a record high of 38.8°C (1995).
Rainfall in July is a relatively wet time of year, averaging 94 mm, with a wettest year of 201 mm.
One of the best times to visit New Castle
July is one of the best times to visit New Castle. Expect days averaging 29.3°C and nights around 16.5°C (mean 22.9°C) — warmer than New Castle's yearly average — with higher rainfall (94 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 | 25.3°C | 18.8°C | 36.4°C | 12.1°C | 73 mm | 69% | 0.1 m/s | 6.1 |
| 2024 | 31.3°C | 24.3°C | 17.3°C | 35.2°C | 11.4°C | 72 mm | 64% | 0.1 m/s | 6.1 |
| 2023 | 29.9°C | 23.5°C | 17.2°C | 35.0°C | 12.9°C | 120 mm | 69% | 0.1 m/s | 5.8 |
| 2022 | 30.7°C | 24.0°C | 17.3°C | 34.3°C | 12.8°C | 85 mm | 65% | 0.1 m/s | 6.3 |
| 2021 | 28.8°C | 22.8°C | 16.7°C | 34.2°C | 11.4°C | 116 mm | 71% | 0.1 m/s | 5.4 |
| 2020 🔥 | 32.3°C | 25.7°C | 19.0°C | 36.7°C | 14.0°C | 58 mm | 64% | 0.1 m/s | 6.5 |
| 2019 | 29.2°C | 23.7°C | 18.1°C | 35.1°C | 13.0°C | 106 mm | 79% | 0.1 m/s | 6.2 |
| 2018 | 30.0°C | 23.6°C | 17.3°C | 36.0°C | 10.9°C | 65 mm | 70% | 0.1 m/s | 6.3 |
| 2017 | 28.9°C | 23.0°C | 17.0°C | 33.6°C | 12.2°C | 74 mm | 74% | 0.1 m/s | 5.8 |
| 2016 | 31.3°C | 24.5°C | 17.7°C | 36.3°C | 10.7°C | 64 mm | 66% | 0.1 m/s | 6.1 |
| 2015 | 28.5°C | 22.2°C | 15.9°C | 34.7°C | 8.9°C | 63 mm | 74% | 0.1 m/s | 6.1 |
| 2014 | 26.8°C | 20.7°C | 14.6°C | 33.2°C | 8.9°C | 86 mm | 72% | 0.1 m/s | 5.5 |
| 2013 | 27.8°C | 22.6°C | 17.5°C | 34.2°C | 9.4°C | 129 mm | 79% | 0.1 m/s | 5.4 |
| 2012 | 32.5°C | 25.6°C | 18.7°C | 37.7°C | 14.0°C | 117 mm | 62% | 0 m/s | 5.9 |
| 2011 | 31.5°C | 24.9°C | 18.3°C | 35.8°C | 12.2°C | 74 mm | 71% | 0.1 m/s | 6.4 |
| 2010 | 31.4°C | 24.5°C | 17.5°C | 36.1°C | 8.8°C | 73 mm | 64% | 0.1 m/s | 6.3 |
| 2009 | 26.2°C | 20.3°C | 14.3°C | 30.9°C | 10.8°C | 93 mm | 70% | 0.1 m/s | 5.4 |
| 2008 | 28.2°C | 22.3°C | 16.4°C | 32.0°C | 11.6°C | 108 mm | 74% | 0.1 m/s | 6.2 |
| 2007 | 28.7°C | 21.7°C | 14.7°C | 34.0°C | 8.4°C | 70 mm | 63% | 0.1 m/s | 5.7 |
| 2006 | 28.3°C | 22.8°C | 17.3°C | 36.4°C | 10.1°C | 147 mm | 77% | 0.1 m/s | 5.5 |
| 2005 | 30.7°C | 24.1°C | 17.6°C | 34.1°C | 13.1°C | 94 mm | 68% | 0.1 m/s | 6 |
| 2004 | 26.8°C | 21.4°C | 16.0°C | 32.8°C | 11.2°C | 117 mm | 78% | 0.1 m/s | 5 |
| 2003 | 27.1°C | 21.4°C | 15.8°C | 31.9°C | 10.4°C | 196 mm | 77% | 0.1 m/s | 5.4 |
| 2002 | 31.8°C | 24.7°C | 17.7°C | 35.7°C | 10.0°C | 50 mm | 60% | 0.1 m/s | 6.4 |
| 2001 | 29.9°C | 22.4°C | 14.8°C | 35.6°C | 7.6°C | 44 mm | 59% | 0.1 m/s | 6.3 |
| 2000 | 27.6°C | 20.9°C | 14.1°C | 31.5°C | 9.2°C | 76 mm | 67% | 0.1 m/s | 5.7 |
| 1999 | 32.5°C | 25.2°C | 18.0°C | 36.6°C | 10.3°C | 115 mm | 60% | 0.1 m/s | 6.3 |
| 1998 | 28.9°C | 22.4°C | 15.9°C | 32.6°C | 10.4°C | 54 mm | 66% | 0.1 m/s | 6.1 |
| 1997 | 29.1°C | 22.3°C | 15.6°C | 33.7°C | 9.7°C | 33 mm | 68% | 0.1 m/s | 5.9 |
| 1996 | 26.0°C | 20.2°C | 14.3°C | 30.1°C | 8.8°C | 100 mm | 75% | 0 m/s | 6 |
| 1995 | 28.6°C | 22.8°C | 17.0°C | 38.8°C | 10.0°C | 92 mm | 75% | 0.1 m/s | 5.6 |
| 1994 | 29.1°C | 23.1°C | 17.1°C | 32.8°C | 11.5°C | 74 mm | 70% | 0.1 m/s | 5.5 |
| 1993 | 30.4°C | 23.9°C | 17.4°C | 35.8°C | 11.6°C | 62 mm | 67% | 0 m/s | 5.8 |
| 1992 🌧️ | 27.2°C | 21.6°C | 16.1°C | 33.9°C | 10.9°C | 201 mm | 77% | 0 m/s | 4.6 |
| 1991 | 30.2°C | 23.3°C | 16.4°C | 36.0°C | 11.3°C | 86 mm | 64% | 0.1 m/s | 6.2 |
| 1990 | 26.7°C | 20.8°C | 15.0°C | 32.5°C | 9.1°C | 192 mm | 78% | 0.1 m/s | 5 |
| 1989 | 27.9°C | 22.3°C | 16.6°C | 33.9°C | 11.1°C | 59 mm | 77% | 0.1 m/s | 5.7 |
| 1988 | 31.9°C | 24.6°C | 17.3°C | 38.6°C | 8.4°C | 118 mm | 58% | 0.1 m/s | 5.8 |
| 1987 | 29.7°C | 23.5°C | 17.4°C | 35.3°C | 11.1°C | 81 mm | 73% | 0 m/s | 6 |
| 1986 | 28.3°C | 22.2°C | 16.1°C | 32.4°C | 8.3°C | 131 mm | 76% | 0.1 m/s | 5.5 |
| 1985 | 27.8°C | 21.1°C | 14.5°C | 32.2°C | 8.7°C | 107 mm | 71% | 0.1 m/s | 5.5 |
| 1984 ❄️ | 26.1°C | 20.0°C | 13.9°C | 32.5°C | 10.1°C | 113 mm | 74% | 0.1 m/s | 4.7 |
| 1983 | 29.4°C | 23.0°C | 16.6°C | 33.1°C | 8.7°C | 91 mm | 72% | 0.1 m/s | — |
| 1982 | 29.7°C | 23.0°C | 16.2°C | 34.0°C | 9.5°C | 60 mm | 69% | 0.1 m/s | — |
| 1981 | 28.8°C | 22.2°C | 15.7°C | 33.1°C | 7.9°C | 105 mm | 70% | 0.1 m/s | — |
Actual recorded July data for each year, 1981–2025 — sourced from NASA POWER.
The average high in July is around 29.3°C with lows near 16.5°C (mean 22.9°C), based on 45 years of NASA POWER data.
July averages 94 mm of rainfall in New Castle, a relatively wet time of year. The wettest on record was 201 mm in 1992.
The hottest July reached 38.8°C in 1995. The coldest dipped to 7.6°C in 2001.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average July temperatures have risen by about 2.1°C. Daytime highs moved from 28.4°C to 30.5°C and overnight lows from 15.4°C to 17.5°C over the same span.
July is one of the warmer months of the year in New Castle and a relatively wet time of year, so plan for around 29.3°C daytime highs and 16.5°C at night.
Not quite — July is the 12th coolest month in New Castle, averaging 22.9°C.
For July in New Castle, pack light layers you can adjust through the day, with typical highs of 29.3°C and lows of 16.5°C. Bring an umbrella or light rain jacket too.
Relative humidity in July averages 70% — moderately humid.
Average wind speed in July is 0.1 m/s. The windiest July on record averaged 0.1 m/s (1981).
The wettest July on record was 1992 with 201 mm. On average, July sees 94 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 July, 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 July specifically, along with year-by-year records and how the month has changed over the decades.
