June is one of the warmer months of the year in New Castle, with average highs near 26.3°C and lows around 13.9°C (mean 20.1°C). It is a relatively wet time of year, averaging 101 mm of rainfall and 73% relative humidity across the period.
June is one of the warmer months of the year in New Castle. Across 45 years of records, the warmest June in New Castle was 2021 — when the month averaged 22.3°C — while the coldest was 1985 at 17.2°C. Typical June days reach 26.3°C with nights near 13.9°C. The long-term trend is warming, about 0.4°C per decade.
June is a relatively wet time of year in New Castle, averaging 101 mm of rainfall. The wettest June on record was 2019 with 214 mm, while the driest was 1988 at 22 mm.
Relative humidity in New Castle during June averages 73%. The most humid June was 1989 at 82%, and the least humid was 1988 at 53%.
June receives about 5.8 kWh/m²/day of solar energy in New Castle. The sunniest June was 1988 at 7.1 kWh/m²/day, and the cloudiest was 2015 at 4.8.
Average wind speed in New Castle during June is 0.1 m/s. The windiest Junes were 2022, 2023 and 2025, among others at 0.1 m/s, while the calmest were 2015, 2020 and 2024, 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 | 19.2°C | 20.0°C | 20.0°C | 20.5°C | 21.1°C | +1.9°C |
| Avg High | 25.5°C | 26.3°C | 26.1°C | 26.5°C | 27.5°C | +2°C |
| Avg Low | 12.9°C | 13.7°C | 13.8°C | 14.6°C | 14.7°C | +1.8°C |
| Avg Rain | 116 mm | 93 mm | 90 mm | 118 mm | 81 mm | -35 mm |
June temperatures in New Castle have risen by about 2.3°C between 1981–1985 and 2021–2025.
June has ranged from a record low of 2.3°C (1986) to a record high of 39.4°C (2025).
Rainfall in June is a relatively wet time of year, averaging 101 mm, with a wettest year of 214 mm.
One of the best times to visit New Castle
June is one of the best times to visit New Castle. Expect days averaging 26.3°C and nights around 13.9°C (mean 20.1°C) — warmer than New Castle's yearly average — with higher rainfall (101 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 | 28.1°C | 22.2°C | 16.4°C | 39.4°C | 3.5°C | 132 mm | 79% | 0.1 m/s | 5.7 |
| 2024 | 28.3°C | 21.6°C | 14.9°C | 36.5°C | 6.8°C | 73 mm | 71% | 0 m/s | 5.8 |
| 2023 | 26.1°C | 19.4°C | 12.6°C | 32.4°C | 7.3°C | 71 mm | 65% | 0.1 m/s | 5.7 |
| 2022 | 27.4°C | 20.6°C | 13.9°C | 33.4°C | 7.0°C | 73 mm | 68% | 0.1 m/s | 6.8 |
| 2021 🔥 | 28.6°C | 22.3°C | 16.0°C | 36.5°C | 8.4°C | 78 mm | 68% | 0.1 m/s | 5.8 |
| 2020 | 26.7°C | 20.5°C | 14.3°C | 32.2°C | 3.8°C | 57 mm | 74% | 0 m/s | 6.8 |
| 2019 🌧️ | 24.7°C | 19.2°C | 13.7°C | 32.0°C | 5.2°C | 214 mm | 80% | 0.1 m/s | 5.9 |
| 2018 | 27.0°C | 21.2°C | 15.3°C | 35.4°C | 7.1°C | 104 mm | 79% | 0.1 m/s | 5.4 |
| 2017 | 25.9°C | 20.1°C | 14.4°C | 32.4°C | 8.4°C | 119 mm | 75% | 0.1 m/s | 6.1 |
| 2016 | 28.1°C | 21.4°C | 14.7°C | 33.9°C | 7.3°C | 63 mm | 66% | 0.1 m/s | 6.6 |
| 2015 | 25.4°C | 20.0°C | 14.5°C | 31.9°C | 8.0°C | 193 mm | 80% | 0 m/s | 4.8 |
| 2014 | 26.4°C | 20.5°C | 14.5°C | 30.4°C | 7.1°C | 135 mm | 79% | 0 m/s | 5.8 |
| 2013 | 26.5°C | 20.5°C | 14.5°C | 32.6°C | 6.3°C | 139 mm | 74% | 0 m/s | 5.5 |
| 2012 | 28.4°C | 21.3°C | 14.1°C | 36.8°C | 8.1°C | 48 mm | 63% | 0.1 m/s | 6.5 |
| 2011 | 26.0°C | 20.2°C | 14.4°C | 30.6°C | 6.2°C | 66 mm | 77% | 0.1 m/s | 5.9 |
| 2010 | 26.8°C | 21.1°C | 15.4°C | 32.6°C | 7.3°C | 102 mm | 76% | 0.1 m/s | 5.7 |
| 2009 | 25.6°C | 19.3°C | 13.0°C | 31.4°C | 5.7°C | 98 mm | 74% | 0.1 m/s | 5.5 |
| 2008 | 25.5°C | 20.4°C | 15.2°C | 30.9°C | 8.1°C | 133 mm | 79% | 0.1 m/s | 5.6 |
| 2007 | 27.2°C | 20.3°C | 13.4°C | 33.1°C | 7.6°C | 81 mm | 68% | 0 m/s | 6.6 |
| 2006 | 25.0°C | 18.8°C | 12.6°C | 32.2°C | 4.3°C | 109 mm | 74% | 0.1 m/s | 5.8 |
| 2005 | 27.9°C | 21.8°C | 15.8°C | 34.4°C | 9.3°C | 49 mm | 75% | 0 m/s | 6 |
| 2004 | 24.3°C | 18.7°C | 13.0°C | 29.7°C | 5.6°C | 113 mm | 79% | 0 m/s | 5.7 |
| 2003 | 24.1°C | 18.4°C | 12.7°C | 38.0°C | 2.9°C | 73 mm | 77% | 0.1 m/s | 5.2 |
| 2002 | 27.4°C | 20.9°C | 14.5°C | 35.2°C | 7.6°C | 79 mm | 73% | 0.1 m/s | 6.1 |
| 2001 | 27.5°C | 20.6°C | 13.7°C | 34.6°C | 6.3°C | 63 mm | 67% | 0.1 m/s | 6 |
| 2000 | 26.4°C | 20.4°C | 14.4°C | 31.4°C | 6.1°C | 103 mm | 73% | 0.1 m/s | 5.2 |
| 1999 | 29.1°C | 21.6°C | 14.1°C | 36.0°C | 6.9°C | 30 mm | 60% | 0 m/s | 6.1 |
| 1998 | 24.9°C | 19.5°C | 14.0°C | 33.5°C | 3.5°C | 118 mm | 76% | 0.1 m/s | 5.4 |
| 1997 | 25.3°C | 19.5°C | 13.7°C | 32.4°C | 6.5°C | 105 mm | 77% | 0.1 m/s | 5.9 |
| 1996 | 25.7°C | 20.3°C | 14.9°C | 30.8°C | 7.0°C | 150 mm | 80% | 0.1 m/s | 5.3 |
| 1995 | 26.2°C | 20.5°C | 14.8°C | 33.5°C | 6.9°C | 157 mm | 80% | 0.1 m/s | 5.7 |
| 1994 | 27.8°C | 21.0°C | 14.1°C | 35.7°C | 4.0°C | 83 mm | 71% | 0.1 m/s | 6 |
| 1993 | 25.0°C | 18.9°C | 12.7°C | 32.2°C | 5.9°C | 113 mm | 75% | 0 m/s | 5.8 |
| 1992 | 25.6°C | 18.4°C | 11.2°C | 32.3°C | 2.9°C | 29 mm | 66% | 0.1 m/s | 5.7 |
| 1991 | 28.6°C | 21.5°C | 14.4°C | 34.3°C | 8.4°C | 50 mm | 66% | 0 m/s | 6.3 |
| 1990 | 24.4°C | 18.6°C | 12.8°C | 31.7°C | 2.3°C | 97 mm | 78% | 0.1 m/s | 5.4 |
| 1989 | 24.0°C | 19.1°C | 14.1°C | 29.3°C | 7.2°C | 201 mm | 82% | 0.1 m/s | 5 |
| 1988 | 28.0°C | 19.9°C | 11.8°C | 36.3°C | 4.6°C | 22 mm | 53% | 0.1 m/s | 7.1 |
| 1987 | 27.4°C | 21.0°C | 14.6°C | 34.1°C | 5.3°C | 132 mm | 71% | 0 m/s | 5.9 |
| 1986 | 24.9°C | 18.6°C | 12.3°C | 30.2°C | 2.3°C | 139 mm | 75% | 0.1 m/s | 5.4 |
| 1985 ❄️ | 23.3°C | 17.2°C | 11.0°C | 27.9°C | 7.7°C | 84 mm | 74% | 0 m/s | 5.7 |
| 1984 | 26.0°C | 19.9°C | 13.7°C | 31.8°C | 6.8°C | 94 mm | 77% | 0 m/s | 5.8 |
| 1983 | 26.2°C | 19.7°C | 13.2°C | 33.1°C | 3.8°C | 95 mm | 76% | 0.1 m/s | — |
| 1982 | 24.3°C | 18.1°C | 11.9°C | 29.7°C | 8.2°C | 118 mm | 74% | 0.1 m/s | — |
| 1981 | 25.3°C | 19.5°C | 13.7°C | 30.4°C | 4.5°C | 159 mm | 78% | 0.1 m/s | — |
Actual recorded June data for each year, 1981–2025 — sourced from NASA POWER.
The average high in June is around 26.3°C with lows near 13.9°C (mean 20.1°C), based on 45 years of NASA POWER data.
June averages 101 mm of rainfall in New Castle, a relatively wet time of year. The wettest on record was 214 mm in 2019.
The hottest June reached 39.4°C in 2025. The coldest dipped to 2.3°C in 1986.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average June temperatures have risen by about 2.3°C. Daytime highs moved from 25°C to 27.7°C and overnight lows from 12.7°C to 14.8°C over the same span.
June is one of the warmer months of the year in New Castle and a relatively wet time of year, so plan for around 26.3°C daytime highs and 13.9°C at night.
Not quite — June is the 10th coolest month in New Castle, averaging 20.1°C.
For June in New Castle, pack light layers you can adjust through the day, with typical highs of 26.3°C and lows of 13.9°C. Bring an umbrella or light rain jacket too.
Relative humidity in June averages 73% — moderately humid.
Average wind speed in June is 0.1 m/s. The windiest June on record averaged 0.1 m/s (1981).
The wettest June on record was 2019 with 214 mm. On average, June sees 101 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 June, 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 June specifically, along with year-by-year records and how the month has changed over the decades.
