Climate averages 1991–2020
Napa weather
in June.
A hot, very dry month: the 4th warmest and the 4th 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 Napa: daytime highs average 28.9°C and nights cool to about 13.9°C. By daytime temperature it is the 4th warmest of the 12 months.
Expect about 4.7 mm of rain on fewer than one day, which makes June a very dry month (the 4th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 14 h 47 min on an average June day.
The nearest other city in this atlas is Vallejo (22 km away). In June its highs average 27.4°C, 1.5°C cooler than Napa, with 4.2 mm of rain.
Among the 498 cities listed in the United States, Napa ranks joint 196th of 498 for the warmest June highs and joint 108th of 498 for the driest June (rainfall, lowest first). The mean June high of those 498 cities is 27.9°C; Napa is 1.0°C warmer than that mean.
From June to July, average highs rise by 1.7°C to 30.7°C, and monthly rainfall falls from 4.7 mm to under 1 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
Napa climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 14.4°C5.3°C | 5.3°C | 116 | 9.4 | 9.810 h |
| February | 15.9°C6.3°C | 6.3°C | 117 | 8.7 | 10.711 h |
| March | 18.0°C7.5°C | 7.5°C | 86 | 8.4 | 11.912 h |
| April | 20.7°C9.0°C | 9.0°C | 38 | 4.9 | 13.213 h |
| May | 24.6°C11.5°C | 11.5°C | 20 | 3.2 | 14.214 h |
| June, selected | 28.9°C13.9°C | 13.9°C | 4.7 | 0.9 | 14.815 h |
| July | 30.7°C14.7°C | 14.7°C | 0.4 | 0.1 | 14.515 h |
| August | 30.6°C14.9°C | 14.9°C | 0.7 | 0.2 | 13.714 h |
| September | 29.5°C14.6°C | 14.6°C | 2.0 | 0.4 | 12.512 h |
| October | 25.1°C12.6°C | 12.6°C | 26 | 2.9 | 11.211 h |
| November | 18.3°C8.4°C | 8.4°C | 56 | 5.9 | 10.110 h |
| December | 14.2°C5.6°C | 5.6°C | 110 | 9.4 | 9.610 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
- Vallejo in JuneUnited States · 22 kmHigh 27.4°C · Low 12.6°C · 4.2 mm rain
- Fairfield in JuneUnited States · 22 kmHigh 28.4°C · Low 13.5°C · 4.2 mm rain
- Vacaville in JuneUnited States · 27 kmHigh 30.4°C · Low 14.8°C · 4.2 mm rain
- Santa Rosa, United States in JuneUnited States · 41 kmHigh 27.8°C · Low 13.1°C · 7.0 mm rain
- Concord (California), United States in JuneUnited States · 42 kmHigh 27.3°C · Low 13.1°C · 3.7 mm rain
- Berkeley in JuneUnited States · 47 kmHigh 24.9°C · Low 12.2°C · 3.6 mm rain
- Antioch in JuneUnited States · 53 kmHigh 28.5°C · Low 14.0°C · 3.6 mm rain
- Oakland in JuneUnited States · 55 kmHigh 24.8°C · Low 12.6°C · 3.6 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 Napa) is explained once on the Napa year overview and on the Sources, method and limits page.