Climate averages 1991–2020
Rancho Cucamonga weather
in June.
A hot, very dry month: the 4th warmest and the 3rd driest of the year. Meets the pleasant-weather rule
Long-term climate patterns, not a forecast for a particular trip.
June is a hot month in Rancho Cucamonga: daytime highs average 28.9°C and nights cool to about 15.3°C. By daytime temperature it is the 4th warmest of the 12 months.
Expect about 3.4 mm of rain on fewer than one day, which makes June a very dry month (the 3rd driest of the 12 months). Daylight, from sunrise to sunset, lasts about 14 h 23 min on an average June day.
The nearest other city in this atlas is Ontario (7 km away). In June its highs average 28.4°C, 0.5°C cooler than Rancho Cucamonga, with 2.4 mm of rain.
Among the 498 cities listed in the United States, Rancho Cucamonga ranks joint 196th of 498 for the warmest June highs and joint 71st of 498 for the driest June (rainfall, lowest first). The mean June high of those 498 cities is 27.9°C; Rancho Cucamonga is 1.0°C warmer than that mean.
From June to July, average highs rise by 3.4°C to 32.3°C, and monthly rainfall falls from 3.4 mm to 2.2 mm.
The annual picture
June in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Rancho Cucamonga climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 17.2°C5.6°C | 5.6°C | 96 | 6.6 | 10.210 h |
| February | 17.5°C6.1°C | 6.1°C | 111 | 7.4 | 10.911 h |
| March | 19.5°C7.7°C | 7.7°C | 68 | 6.8 | 12.012 h |
| April | 22.0°C9.4°C | 9.4°C | 32 | 4.6 | 13.013 h |
| May | 24.8°C12.2°C | 12.2°C | 15 | 2.6 | 13.914 h |
| June, selected | 28.9°C15.3°C | 15.3°C | 3.4 | 0.5 | 14.414 h |
| July | 32.3°C18.7°C | 18.7°C | 2.2 | 0.5 | 14.214 h |
| August | 33.3°C19.2°C | 19.2°C | 1.1 | 0.3 | 13.413 h |
| September | 31.4°C17.4°C | 17.4°C | 5.5 | 1.2 | 12.412 h |
| October | 26.4°C13.2°C | 13.2°C | 22 | 3.1 | 11.411 h |
| November | 21.3°C8.8°C | 8.8°C | 30 | 3.5 | 10.410 h |
| December | 16.9°C5.4°C | 5.4°C | 67 | 5.8 | 9.910 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
June in nearby cities
- Ontario in JuneUnited States · 7 kmHigh 28.4°C · Low 15.3°C · 2.4 mm rain
- Chino in JuneUnited States · 14 kmHigh 27.5°C · Low 15.1°C · 2.4 mm rain
- Fontana in JuneUnited States · 15 kmHigh 29.0°C · Low 15.0°C · 3.4 mm rain
- Pomona in JuneUnited States · 16 kmHigh 27.5°C · Low 14.7°C · 2.4 mm rain
- Chino Hills in JuneUnited States · 20 kmHigh 26.8°C · Low 14.9°C · 2.4 mm rain
- Riverside in JuneUnited States · 25 kmHigh 29.3°C · Low 15.4°C · 3.4 mm rain
- Corona in JuneUnited States · 26 kmHigh 28.7°C · Low 15.6°C · 3.4 mm rain
- San Bernardino in JuneUnited States · 28 kmHigh 29.5°C · Low 15.7°C · 3.5 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Rancho Cucamonga) is explained once on the Rancho Cucamonga year overview and on the Sources, method and limits page.
Riverside, Fontana and Corona lie in the same rainfall cell, so their rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.