The highest day temperature in March 2026 was 88°F. The lowest night temperature was 44°F. The average values for day and night temperatures during March were 75.8°F и 51.7°F respectivly.

Most of the days in March are sunny but you can also expect cloudy and gloomy days.

Precipitation total in March for Napa is 0.8 in. It makes march one of the most rainy months of the year.

The average wind speed in March is 4.8 mph. This value is relatively stable throughout the year.

We are using day length and cloud cover information for each day of the month to calculate averages for this chart. Average sunny hours for Napa in March is 7.5 hours.