April is one of the cooler months of the year in Rancho Cucamonga, with average highs near 23.3°C and lows around 8.2°C (mean 15.8°C). It is about average for rainfall, averaging 19 mm of rainfall and 57% relative humidity across the period.
April is one of the cooler months of the year in Rancho Cucamonga. Across 45 years of records, the warmest April in Rancho Cucamonga was 1989 — when the month averaged 19.2°C — while the coldest was 1983 at 11.6°C. Typical April days reach 23.3°C with nights near 8.2°C. The long-term trend is warming, about 0.2°C per decade.
April is about average for rainfall in Rancho Cucamonga, averaging 19 mm of rainfall. The wettest April on record was 2020 with 91 mm, while the driest was 1993 at 0 mm.
Relative humidity in Rancho Cucamonga during April averages 57%. The most humid April was 2020 at 69%, and the least humid was 1987 at 43%.
April receives about 6.8 kWh/m²/day of solar energy in Rancho Cucamonga. The sunniest April was 2008 at 7.4 kWh/m²/day, and the cloudiest was 1988 at 5.7.
Average wind speed in Rancho Cucamonga during April is 2 m/s. The windiest April was 1983 at 2.3 m/s, while the calmest were 1992, 1993 and 2023 at 1.6 m/s.
Ranked against the other 11 months using 1981–2025 averages.
| Metric | 1980s | 1990s | 2000s | 2010s | 2020s | Change |
|---|---|---|---|---|---|---|
| Avg Temp | 15.9°C | 15.3°C | 15.1°C | 16.4°C | 16.1°C | +0.2°C |
| Avg High | 23.7°C | 22.8°C | 22.6°C | 23.9°C | 23.4°C | -0.3°C |
| Avg Low | 8.1°C | 7.8°C | 7.7°C | 8.8°C | 8.9°C | +0.8°C |
| Avg Rain | 27 mm | 16 mm | 20 mm | 12 mm | 20 mm | -6 mm |
April temperatures in Rancho Cucamonga have risen by about 1.1°C between 1981–1985 and 2021–2025.
April has ranged from a record low of -1.4°C (1999) to a record high of 35.9°C (1989).
Rainfall in April is about average for rainfall, averaging 19 mm, with a wettest year of 91 mm.
A good time to visit Rancho Cucamonga
April is a good time to visit Rancho Cucamonga, with days averaging 23.3°C and nights around 8.2°C (mean 15.8°C, cooler than Rancho Cucamonga's yearly average) and low rainfall. June and October are marginally more temperate, but April still suits most travellers.
| Year | Avg High | Avg Temp | Avg Low | Hottest Day | Coldest Day | Rainfall | Humidity | Wind | Solar |
|---|---|---|---|---|---|---|---|---|---|
| 2025 | 22.7°C | 15.7°C | 8.8°C | 31.3°C | 3.4°C | 6 mm | 59% | 1.9 m/s | 6.8 |
| 2024 | 21.7°C | 14.7°C | 7.8°C | 28.8°C | 0.5°C | 15 mm | 67% | 1.8 m/s | 7 |
| 2023 | 22.9°C | 15.6°C | 8.4°C | 30.0°C | 0.0°C | 2 mm | 62% | 1.6 m/s | 7.2 |
| 2022 | 25.6°C | 17.4°C | 9.2°C | 34.8°C | 2.7°C | 6 mm | 54% | 2.1 m/s | 7.3 |
| 2021 | 25.3°C | 17.3°C | 9.3°C | 35.1°C | 4.6°C | 2 mm | 51% | 1.9 m/s | 7.2 |
| 2020 🌧️ | 22.3°C | 16.1°C | 9.9°C | 33.6°C | 4.4°C | 91 mm | 69% | 1.9 m/s | 6.3 |
| 2019 | 23.0°C | 16.3°C | 9.6°C | 30.0°C | 5.9°C | 3 mm | 65% | 1.9 m/s | 6.9 |
| 2018 | 25.1°C | 17.2°C | 9.3°C | 32.8°C | 2.1°C | 1 mm | 50% | 2 m/s | 7.1 |
| 2017 | 24.6°C | 16.9°C | 9.3°C | 30.7°C | 2.2°C | 2 mm | 56% | 1.9 m/s | 7.1 |
| 2016 | 24.4°C | 17.3°C | 10.2°C | 32.3°C | 4.0°C | 15 mm | 52% | 1.9 m/s | 6.7 |
| 2015 | 24.7°C | 17.0°C | 9.2°C | 33.2°C | 4.2°C | 7 mm | 49% | 1.9 m/s | 7.1 |
| 2014 | 25.4°C | 17.4°C | 9.4°C | 32.1°C | 3.4°C | 14 mm | 47% | 2 m/s | 7.1 |
| 2013 | 25.4°C | 17.0°C | 8.6°C | 32.8°C | 3.0°C | 2 mm | 51% | 2 m/s | 7.2 |
| 2012 | 24.7°C | 16.6°C | 8.5°C | 34.6°C | 0.9°C | 33 mm | 51% | 2 m/s | 7 |
| 2011 | 21.9°C | 14.9°C | 7.9°C | 31.1°C | 1.6°C | 4 mm | 64% | 2 m/s | 6.9 |
| 2010 | 20.0°C | 13.0°C | 6.0°C | 27.6°C | 0.9°C | 35 mm | 64% | 2.1 m/s | 7 |
| 2009 | 22.6°C | 14.8°C | 7.0°C | 35.1°C | 1.0°C | 3 mm | 55% | 2 m/s | 7.1 |
| 2008 | 24.0°C | 15.7°C | 7.4°C | 32.5°C | 2.6°C | 0 mm | 51% | 2 m/s | 7.4 |
| 2007 | 24.2°C | 16.3°C | 8.5°C | 35.3°C | 3.5°C | 14 mm | 51% | 1.9 m/s | 6.7 |
| 2006 | 20.3°C | 13.8°C | 7.4°C | 29.2°C | 2.6°C | 42 mm | 67% | 2.1 m/s | 6.3 |
| 2005 | 21.3°C | 14.3°C | 7.4°C | 27.2°C | 3.5°C | 15 mm | 63% | 2 m/s | 7 |
| 2004 | 24.7°C | 16.9°C | 9.1°C | 35.7°C | 4.9°C | 14 mm | 55% | 1.8 m/s | 7 |
| 2003 | 19.5°C | 12.9°C | 6.2°C | 27.8°C | 2.5°C | 35 mm | 67% | 2.2 m/s | 6.7 |
| 2002 | 23.1°C | 15.7°C | 8.3°C | 34.7°C | 3.4°C | 8 mm | 56% | 2 m/s | 6.9 |
| 2001 | 20.8°C | 13.9°C | 6.9°C | 32.3°C | 0.0°C | 28 mm | 61% | 2 m/s | 6.7 |
| 2000 | 25.1°C | 17.0°C | 9.0°C | 33.1°C | 4.6°C | 42 mm | 56% | 1.9 m/s | 6.9 |
| 1999 | 20.1°C | 13.1°C | 6.1°C | 33.0°C | -1.4°C | 47 mm | 58% | 2.2 m/s | 6.1 |
| 1998 | 19.1°C | 12.7°C | 6.3°C | 30.2°C | 1.0°C | 30 mm | 67% | 1.9 m/s | 7 |
| 1997 | 24.2°C | 16.1°C | 8.0°C | 32.3°C | 2.1°C | 3 mm | 51% | 2.2 m/s | 6.8 |
| 1996 | 25.8°C | 17.3°C | 8.8°C | 34.4°C | 3.8°C | 11 mm | 48% | 2.1 m/s | 7.3 |
| 1995 | 20.5°C | 13.6°C | 6.7°C | 27.8°C | 1.9°C | 21 mm | 65% | 2.1 m/s | 6.6 |
| 1994 | 23.0°C | 15.7°C | 8.3°C | 31.1°C | 3.2°C | 24 mm | 57% | 1.9 m/s | 6.5 |
| 1993 | 23.5°C | 15.9°C | 8.2°C | 30.1°C | 3.8°C | 0 mm | 61% | 1.6 m/s | 7.1 |
| 1992 | 25.0°C | 17.5°C | 10.0°C | 30.9°C | 6.4°C | 1 mm | 60% | 1.6 m/s | 6.7 |
| 1991 | 21.9°C | 14.3°C | 6.7°C | 29.2°C | 1.7°C | 1 mm | 60% | 2.1 m/s | 6.7 |
| 1990 | 24.5°C | 16.9°C | 9.4°C | 31.6°C | 5.8°C | 18 mm | 59% | 1.9 m/s | 6.2 |
| 1989 🔥 | 27.8°C | 19.2°C | 10.6°C | 35.9°C | 4.6°C | 3 mm | 48% | 1.8 m/s | 6.9 |
| 1988 | 23.1°C | 15.8°C | 8.6°C | 32.4°C | 2.9°C | 65 mm | 54% | 2.2 m/s | 5.7 |
| 1987 | 26.8°C | 18.6°C | 10.3°C | 33.0°C | 4.2°C | 8 mm | 43% | 1.9 m/s | 6.6 |
| 1986 | 22.2°C | 14.6°C | 7.1°C | 30.4°C | 3.0°C | 17 mm | 60% | 2 m/s | 6.7 |
| 1985 | 26.3°C | 17.9°C | 9.4°C | 33.8°C | 4.1°C | 2 mm | 44% | 2 m/s | 7 |
| 1984 | 23.6°C | 15.3°C | 7.0°C | 33.1°C | 1.7°C | 10 mm | 46% | 2.2 m/s | 6.3 |
| 1983 ❄️ | 17.8°C | 11.6°C | 5.4°C | 24.7°C | 0.0°C | 86 mm | 68% | 2.3 m/s | — |
| 1982 | 21.4°C | 14.1°C | 6.8°C | 27.8°C | -0.5°C | 37 mm | 62% | 2.1 m/s | — |
| 1981 | 24.4°C | 16.2°C | 8.1°C | 34.9°C | 2.1°C | 12 mm | 50% | 1.9 m/s | — |
Actual recorded April data for each year, 1981–2025 — sourced from NASA POWER.
The average high in April is around 23.3°C with lows near 8.2°C (mean 15.8°C), based on 45 years of NASA POWER data.
April averages 19 mm of rainfall in Rancho Cucamonga, about average for rainfall. The wettest on record was 91 mm in 2020.
The hottest April reached 35.9°C in 1989. The coldest dipped to -1.4°C in 1999.
Comparing the earliest years on record (1981–1985) with the most recent (2021–2025), average April temperatures have risen by about 1.1°C. Daytime highs moved from 22.7°C to 23.6°C and overnight lows from 7.3°C to 8.7°C over the same span.
April is one of the cooler months of the year in Rancho Cucamonga and about average for rainfall, so plan for around 23.3°C daytime highs and 8.2°C at night.
Not quite — April is the 6th coolest month in Rancho Cucamonga, averaging 15.8°C.
For April in Rancho Cucamonga, pack light layers you can adjust through the day, with typical highs of 23.3°C and lows of 8.2°C.
Relative humidity in April averages 57% — moderately humid.
Average wind speed in April is 2 m/s. The windiest April on record averaged 2.3 m/s (1983).
The wettest April on record was 2020 with 91 mm. On average, April sees 19 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 Rancho Cucamonga behaves each April, 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 April specifically, along with year-by-year records and how the month has changed over the decades.
