Weather in Napa in April

Prime time. April is about as good as Napa gets. Highs average 20.2 °C, lows 8 °C, and rain falls on 6 days — nothing in the month is working against you.

April ranks 3 of 12 in Napa. Only May scores clearly higher, and the difference is small enough to be settled by price rather than weather.

Rain falls on only 6 days, so an itinerary with no wet-weather fallback is a reasonable risk. Nothing specialised needed — this is the month you pack for the trip rather than for the weather.

What the averages hide

The averages here are honest — no hidden extremes worth planning around. Across the twenty years measured, the hottest April day reached 32.4 °C and the coldest night fell to 0.7 °C, and the wettest single day dropped 43 mm — roughly 93% of the month's rain in one day.

This is the volatile part. April rainfall has ranged from 4 mm to 147 mm across the twenty years measured — a 143 mm spread around an average of 46 mm. The average is real but almost no individual April looks like it, so treat the figure as the middle of a wide range rather than a forecast.

Wind is light at 6 km/h, so the temperature on the page is close to the temperature on your skin, and humidity runs at 76%, high enough to notice on the warm days without dominating them.

How April sits in the year

The month is on the way up: 2.4 °C warmer than March, and May adds another 4.7 °C. Late in the month feels noticeably different from the start of it, which is worth knowing if the trip is short.

Daylight in April

13.2 hours of daylight, gaining 1.2 hours across the month. That is between Napa's extremes of 14.8 and 9.5 hours, so days are long enough not to constrain the plan.

An inland climate

With no coast nearby, the year swings a fair way — 28.6 °C between the warmest afternoons and the coldest nights, wider than any coastal city at this latitude would manage.

How busy it gets

Busy. Popular without being frantic; book the things you care about, improvise the rest.

Crowd levels are estimated from climate desirability and school-holiday calendars, not from visitor numbers.

April in Napa versus nearby

If Napa is one option among several, the nearby comparison is worth making. San Francisco is close enough to be a coin toss — 2.8 °C cooler, the same number of rain days. Sacramento is close enough to be a coin toss — within a degree on temperature, the same number of rain days.

So: April is effectively as good as it gets here — 5 points behind May, which is inside the margin where the weather stops being the deciding factor and price starts being it.

Every month in Napa

See all twelve months in Napa, or where else to go in April.