Napa

Napa Valley Weather in August

Average temperatures, rainfall, sunshine and the best places to visit in the Napa Valley, the United States of America in August.

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Napa Calistoga St. Helena Yountville

Planning a journey to the Napa Valley, the United States of America this August and curious over the weather conditions to await? Your essential details are found on this page, answering your query:

What to Expect in the Napa Valley in August

The Napa Valley, the United States of America is a region in the United States of America. August in the Napa Valley generally has temperatures that range from warm to very warm, with almost no precipitation. During August, summer is in full swing.

Temperatures

The average highest temperatures fluctuate between warm in American Canyon at 27°C (81°F) to very warm in Calistoga at 32°C (90°F). Nighttime temperatures generally drop to 12°C (54°F) in Calistoga and 12°C (54°F) in American Canyon.

To explore the conditions in the Napa Valley, the United States of America in more detail, check the map below.

Precipitation

August is a very dry month with an average rainfall of around 0.1 mm (0 in) in Napa. Going by our weather data, this month in Napa usually has the least rain, making it the driest month of the year.

Average sunshine

August brings good sunshine to many areas. Napa sees around 290 hours of sunlight, great for visitors looking for bright days.

Explore the Napa Valley by month

Pick a month to see the average temperature, rainfall and sunshine in the Napa Valley — and find the best time to visit. (based on Napa)

January15°C (59°F) February17°C (63°F) March19°C (66°F) April22°C (72°F) May25°C (77°F) June28°C (82°F) This monthJuly29°C (84°F) August29°C (84°F) September30°C (86°F) October26°C (79°F) November19°C (66°F) December14°C (57°F)
Best Time to Visit the Napa Valley →

Best Places to Visit in the Napa Valley in August

Click on a destination dot for more details. Toggle the map to compare temperatures or precipitation across the Napa Valley.

Conditions Temperatures Precipitation
perfect weather
pleasant
tolerable
unpleasant
poor

Perfect weather is subjective. On this map perfect weather has been defined with temperatures between 20°C (68°F) and 29°C (84°F) and not too much precipitation (less than 90 mm (3.5 in) a month).

Popular Destinations in the Napa Valley

What is the weather like in August for some of the most popular destinations in the Napa Valley, the United States of America?

Temperature range in the Napa Valley (August)

Precipitation variation in the Napa Valley (August)

Napa

In August Napa generally has high temperatures with maximum daytime temperatures around 29°C (84°F), minimum nighttime temperatures around 13°C (55°F) and almost no monthly rainfall. So on average the conditions are perfect that month.

« July
August
September »
July
August
September
Max temperature
29°C (84°F)
29°C (84°F)
30°C (86°F)
Min temperature
13°C (55°F)
13°C (55°F)
12°C (54°F)
Monthly sun hours
306 hours
290 hours
275 hours
Monthly rainfall
0.1 mm (0 in)
0.1 mm (0 in)
3.8 mm (0.1 in)
Monthly rainy days
0 days
0 days
a single day
Weather conditions
perfect
perfect
perfect
Climate in Napa →

Calistoga

In August Calistoga generally has very high temperatures with maximum daytime temperatures around 32°C (90°F), minimum nighttime temperatures around 12°C (54°F) and almost no monthly rainfall. So on average the conditions are perfect that month.

« July
August
September »
July
August
September
Max temperature
32°C (90°F)
32°C (90°F)
31°C (88°F)
Min temperature
13°C (55°F)
12°C (54°F)
11°C (52°F)
Monthly sun hours
306 hours
290 hours
275 hours
Monthly rainfall
0.5 mm (0.02 in)
0.1 mm (0 in)
5.2 mm (0.2 in)
Monthly rainy days
0 days
0 days
a single day
Weather conditions
perfect
perfect
perfect
Climate in Calistoga →

St. Helena

In August St. Helena generally has very high temperatures with maximum daytime temperatures around 31°C (88°F), minimum nighttime temperatures around 13°C (55°F) and almost no monthly rainfall. So on average the conditions are perfect that month.

« July
August
September »
July
August
September
Max temperature
32°C (90°F)
31°C (88°F)
31°C (88°F)
Min temperature
13°C (55°F)
13°C (55°F)
12°C (54°F)
Monthly sun hours
306 hours
290 hours
275 hours
Monthly rainfall
0.4 mm (0.02 in)
0 mm (0 in)
4.2 mm (0.2 in)
Monthly rainy days
0 days
0 days
2 days
Weather conditions
perfect
perfect
perfect
Climate in St. Helena →

Yountville

In August Yountville generally has very high temperatures with maximum daytime temperatures around 31°C (88°F), minimum nighttime temperatures around 12°C (54°F) and almost no monthly rainfall. So on average the conditions are perfect that month.

« July
August
September »
July
August
September
Max temperature
32°C (90°F)
31°C (88°F)
30°C (86°F)
Min temperature
13°C (55°F)
12°C (54°F)
11°C (52°F)
Monthly sun hours
306 hours
290 hours
275 hours
Monthly rainfall
0.2 mm (0.01 in)
0 mm (0 in)
4.5 mm (0.2 in)
Monthly rainy days
0 days
0 days
a single day
Weather conditions
perfect
perfect
perfect
Climate in Yountville →

American Canyon

In August American Canyon generally has high temperatures with maximum daytime temperatures around 27°C (81°F), minimum nighttime temperatures around 12°C (54°F) and almost no monthly rainfall. So on average the conditions are perfect that month.

« July
August
September »
July
August
September
Max temperature
27°C (81°F)
27°C (81°F)
28°C (82°F)
Min temperature
13°C (55°F)
12°C (54°F)
11°C (52°F)
Monthly sun hours
313 hours
288 hours
270 hours
Monthly rainfall
0.2 mm (0.01 in)
0.1 mm (0 in)
3.5 mm (0.1 in)
Monthly rainy days
0 days
0 days
a single day
Weather conditions
perfect
perfect
perfect
Climate in American Canyon →

Is your destination not in the list? Have a look at all destinations in the Napa Valley, in the United States of America.

Popular cities in August

Day & night temperatures, rainfall and average weather in the Napa Valley in August.

City Weather Day temp Night temp Rainfall
Napa 29°C (84°F) 13°C (55°F) 0.1 mm (0 in)
Calistoga 32°C (90°F) 12°C (54°F) 0.1 mm (0 in)
St. Helena 31°C (88°F) 13°C (55°F) 0 mm (0 in)
Yountville 31°C (88°F) 12°C (54°F) 0 mm (0 in)
American Canyon 27°C (81°F) 12°C (54°F) 0.1 mm (0 in)

The Napa Valley weather in August: frequently asked questions

What is the weather like in the Napa Valley, the United States of America in August?

August in the Napa Valley, the United States of America brings perfect weather. In Napa, daytime temperatures are typically around 29°C (84°F) and nighttime lows hover near 13°C (55°F).

What is the average temperature in the Napa Valley, the United States of America in August?

Average temperatures in the Napa Valley, the United States of America during August range from a nighttime low near 13°C (55°F) to a daytime high around 29°C (84°F) in Napa.

Does the Napa Valley, the United States of America get a lot of rain in August?

August is on the drier side in the Napa Valley, the United States of America. Napa averages only about 0.1 mm (0 in), with most days staying dry.

Is August a Good Time to Visit the Napa Valley, the United States of America?

We consider August to be one of the best times to travel to the Napa Valley, the United States of America. Typically, the climate in Napa is perfect.

Generally speaking, April, May, June, July, August and October provide perfect weather in Napa. On the other hand, the weather in February and December tend to be unpleasant.

Interested in more climate information?

We have much more information about the climate in the Napa Valley.

Weather and climate has detailed information for every country in the world. Are you going to the United States of America? Get detailed historical weather averages for many cities in the United States of America.

Not sure yet where to go? We now have a tool which recommends destinations that suit your ideal travel conditions. Find out where to go with our weather planner.

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