Best time to visit Napa

Re-score for me — drag the dial — every chart on the page recolours live for your heat limit 27°C
I'm comfortable up to 27°C feels-like
22° heat-averse 30° heat-loving

Default 27 °C is the upper edge of the Holiday Climate Index "ideal comfort" band (Scott, Rutty, Amelung & Tang, 2016). Above this, most warm-tourism travellers report measurable discomfort.

Saved to this browser. Changes update the strips below.
Recent · 2020-2024
Interest Google Trends 2021-2025 searches, not arrivals (?)
Day · avg daily high (?)
Night · avg overnight low (?)
Heatwaves · days/yr ≥35°C ETCCDI TX35 (?)
<125442
Tropical nights · nights/yr ≥20°C ETCCDI TR20 — sleep killer (?)
<11
UV index · On a typical day around midday, UV is about this (?)
2346891096422
On the sunniest 1 in 10 days, UV reaches this — and even higher
46893
PM2.5 air quality · on a typical day (?)
777767787789
On the worst 1 in 10 days, PM2.5 reaches this — and even higher
13121111810101210111318
May 10/10 feels 24°C (+1°C vs 1991-2020) · HCI 98/100
Day 25° · Night 10° · cools 15° at night ⚠ <1 days/yr ≥35° · peak 2 in worst year 45% humidity 17 km/h wind 3 rain days (32h) 296h sun
Thermal 9
Sky 10
Rain 10
Wind 10

Higher = better, including rain & wind (green = "doesn't hurt the score", not "lots of it").

Compare with another destination

Add as many as you like — stacked below the main strips above. Each row is just the recent-window score strip and (for beach destinations) sea-temperature strip.

Tours in Napa

30 top-rated tours via Viator. Booking links earn this site a commission at no cost to you. Map locations are approximate (centred on Napa).

  1. 1#1 Sonoma Walking Food, Wine Tasting & History Tour (Public Tour)4.96★ (476)3hfrom $189🔥 Selling fast
  2. 2Napa Valley Daily Join In Group Wineries Tour Including Lunch4.44★ (481)from $135🔥 Selling fast
  3. 3Napa & Sonoma Wine Tour | 6-8hr Private Fully Customized.*XL SUV4.71★ (49)8hfrom $233
  4. 46 Hour Private Customized Wine Tour up to 7 Guests Napa & Sonoma4.93★ (89)6hfrom $540
  5. 56 Hour Napa or Sonoma Valley Wine Tour by Private SUV4.86★ (259)12hfrom $390
  6. 66-Hour Private Limousine Wine Country Tour of Napa or Sonoma4.99★ (141)6hfrom $799
  7. 7Best Private Wine Tour of Napa and Sonoma: Up to 8 People4.93★ (125)5hfrom $400
  8. 8Napa Valley's Best Wine Tour w/ Local Expert4.98★ (111)7hfrom $1300
  9. 9Sonoma and Napa 6hr-8hr- Private Wine Tour with Concierge Service4.85★ (144)8h 15mfrom $449
  10. 106-Hour Exclusive Wine Tour Experience: Up to 6 Guests5.00★ (81)6hfrom $560
  11. 11Zero Proof Libations and Food Tour of Downtown Napa5.00★ (17)2hfrom $159🔥 Selling fast
  12. 126-hour Private Luxury SUV Wine Tour in Napa Or Sonoma Valley4.90★ (68)6hfrom $450
  13. 13Napa Valley and Sonoma Wine Tour4.91★ (67)from $618
  14. 14Private Sailing Tour of Bodega Bay4.84★ (90)3hfrom $123
  15. 158 Hour Private Customized Wine Tour up to 7 Guests Napa & Sonoma5.00★ (40)8hfrom $675
  16. 16Fabulous Private Wine Tour of Napa & Sonoma: 2 to 5 People4.89★ (61)5hfrom $400
  17. 176-Hour Private Wine Country Tour of Napa Valley (up to 6 people) in Large SUV4.98★ (46)6hfrom $699
  18. 18Wine & Wellness Tour in Napa Valley4.98★ (48)6hfrom $550
  19. 19Napa Valley Small Group Winery Tour4.89★ (1,052)7hfrom $151
  20. 20Safari West Sonoma Adventure Tour4.64★ (125)3hfrom $110
  21. 218-Hour Exclusive Wine Tour Experience for up to 6 Guests / Napa-Sonoma5.00★ (36)8hfrom $730
  22. 22Sonoma Valley Open Air Wine Trolley Tour4.59★ (872)6h 30mfrom $145
  23. 23Sonoma Wine Country Electric Trike & Wine Tour - 3 hours4.84★ (355)3hfrom $175
  24. 24Wine Country Join-in Flight4.83★ (281)4hfrom $325
  25. 25Napa Valley Wine Trolley Classic Tour4.52★ (786)6h 30mfrom $145
  26. 26Sonoma Valley Pedal Assist Bike Tour with Lunch4.98★ (168)from $179
  27. 276-Hour Private Limousine Tour to Napa and Sonoma Valley Wineries4.79★ (39)from $859
  28. 28Napa Valley Luxury Wine Tours & Car Services5.00★ (24)6hfrom $500
  29. 29Private Guided Wine Tour of Napa Valley5.00★ (17)6hfrom $585
  30. 30Transportation services for Napa . Sonoma wine tours5.00★ (3)5hfrom $400🔥 Selling fast

Last refreshed 2026-08-13.

Similar climatesMijas92% · Granada92% · Izmir91%

Other destinations with the most-alike year-round climate to Napa (apparent temperature, rain hours, sunshine — matched within the same trip-profile). The ±N chip compares each match's typical score for the current month against Napa's. Based on the 2020-2024 climatology, not this year's actual weather.

Month-by-month

Month Temp °C Feels °C Rain days Rain h Rain h/day Humidity Wind km/h Sun h UV Interest Score
Jan 5–15 13 9 119 13.2 70% 13 153 2 Quiet 7
Feb 5–17 15 6 74 12.3 58% 14 189 3 Quiet 8
Mar 6–17 15 10 139 13.9 59% 15 208 4 Quiet 7
Apr 7–21 19 3 39 13.0 52% 15 260 6 Moderate 10
May 10–25 24 3 32 10.7 45% 17 296 8 Busy 10
Jun 13–28 27 1 6 6.0 41% 17 300 9 Busy 10
Jul 13–30 31 0 1 42% 15 306 10 Peak 7
Aug 14–31 31 0 5 42% 15 289 9 Peak 7
Sep 14–30 30 1 14 14.0 42% 14 254 6 Moderate 8
Oct 11–26 25 3 32 10.7 43% 13 224 4 Quiet 10
Nov 6–18 17 6 68 11.3 55% 12 188 2 Quiet 8
Dec 5–14 13 12 145 12.1 72% 11 146 2 Quiet 6

UV Index in Napa by Month

UV index in Napa peaks at 10 (very high) in July, dropping to 2 (low) in December. June, July, August reach very high or extreme levels — apply SPF 50+, wear a hat and protective clothing, and limit direct sun between 11:00 and 17:00.

Best months in detail

May

10/10

10–25°C (feels 24°C) · 3 rain days (32h) · 296 sun hours · 45% humidity · Busy crowd · UV 8 (high) · sunniest 1 in 10 days reach 9 (very high)

April

10/10

7–21°C (feels 19°C) · 3 rain days (39h) · 260 sun hours · 52% humidity · Moderate crowd · UV 6 (high) · sunniest 1 in 10 days reach 8 (high)

October

10/10

11–26°C · 3 rain days (32h) · 224 sun hours · 43% humidity · Quiet crowd · UV 4 (moderate)

Every month

Show the other 9 months in detail

January

7/10

5–15°C (feels 13°C) · 9 rain days (119h) · 153 sun hours · 70% humidity · Quiet crowd · UV 2 (low)

February

8/10

5–17°C (feels 15°C) · 6 rain days (74h) · 189 sun hours · 58% humidity · Quiet crowd · UV 3 (low) · sunniest 1 in 10 days reach 4 (moderate)

March

7/10

6–17°C (feels 15°C) · 10 rain days (139h) · 208 sun hours · 59% humidity · Quiet crowd · UV 4 (moderate) · sunniest 1 in 10 days reach 6 (high)

June

10/10

13–28°C · 1 rain days (6h) · 300 sun hours · 41% humidity · Busy crowd · UV 9 (very high)

July

7/10

13–30°C · 0 rain days (1h) · 306 sun hours · 42% humidity · Peak crowd · UV 10 (very high)

August

7/10

14–31°C · 0 rain days (5h) · 289 sun hours · 42% humidity · Peak crowd · UV 9 (very high)

September

8/10

14–30°C · 1 rain days (14h) · 254 sun hours · 42% humidity · Moderate crowd · UV 6 (high)

November

8/10

6–18°C (feels 17°C) · 6 rain days (68h) · 188 sun hours · 55% humidity · Quiet crowd · UV 2 (low) · sunniest 1 in 10 days reach 3 (moderate)

December

6/10

5–14°C (feels 13°C) · 12 rain days (145h) · 146 sun hours · 72% humidity · Quiet crowd · UV 2 (low)

Harvest season and fire season now overlap

Napa's harvest — the crush — runs from around August into October, whites and sparkling first, cabernet and the other reds last. It is the valley's most atmospheric season: the wineries are working, the air smells of fermentation, and there are harvest dinners and grape stomps for visitors.

It is also, increasingly, fire season. Over the past several years the peak smoke-exposure period has landed in September and October, exactly when the red varieties are ripening. Smoke does not merely look bad — it taints fruit, and losses have run into the hundreds of millions of dollars in a bad year.

For a visitor this means the most rewarding month to come is also the one carrying the most weather risk, and that risk is invisible in a temperature or rainfall average.

Sources: Visit Napa Valley — harvest season , The Drinks Business — wildfires threaten vineyards as harvest approaches

How many days do you need in Napa?

Two to three. Most visitors manage three or four wineries a day at most, and tastings are appointment-based rather than drop-in, so the schedule fills faster than you expect. Three days lets you cover Napa, Yountville and St Helena without rushing. Arrange a driver or a tour — the valley has no useful public transport and tastings involve alcohol.

What is the cheapest time to go to Napa Valley?

January to March. Rates drop sharply, tasting rooms are quiet enough for a real conversation with the pourer rather than a queue, and the mustard blooms bright yellow between the bare vines. The trade-off is cooler, wetter weather — February averages about 125 mm — and no harvest activity, so the valley feels dormant rather than working.

Is it better to visit Napa during harvest?

For atmosphere, yes — roughly August to October is when the valley is actually working, with fruit coming in and the crush under way. The caveat is real: September and October now carry the highest wildfire and smoke risk in California, which can affect air quality and occasionally access, so book flexibly and check conditions before travelling.

What is the hottest month in Napa?

July, averaging about 30C by day and dropping sharply overnight — that diurnal swing is precisely what the vineyards depend on. It is also completely dry, averaging around 0 mm of rain in July. Tastings are comfortable because barrel rooms and caves stay cool regardless of the afternoon outside.

Which month is the rainiest in Napa, CA?

February, at around 125 mm. Napa has a Mediterranean pattern with essentially all its rain between November and April and a bone-dry summer. Winter visits are green, quiet and much cheaper, with tasting rooms far easier to book — the trade-off is bare vines rather than fruit.

Is it better to stay in Napa or the neighbouring valley?

Napa town has the most hotels and restaurants and the shortest drives between big-name wineries. The neighbouring valley is more rural and lower-key, with smaller family producers and lower prices. Napa suits a first visit and marquee names; the alternative suits repeat visitors after something quieter.

Can I wear jeans to Napa wineries?

Yes — smart-casual is the norm and jeans are entirely acceptable at almost every tasting room. What matters more is footwear if you are touring vineyards, and layers: mornings and evenings are cool even in summer, and the caves where tastings often happen stay cold year-round.

When should you not visit Napa?

Late summer through autumn carries wildfire risk in California, which can affect air quality and occasionally access — worth checking conditions before travelling in that window. Harvest itself, roughly late August to October, is the busiest and most expensive time, though also the most atmospheric.

What not to miss in Napa Valley?

A tasting at one of the older estates and one at a small producer for contrast, the Napa Valley Wine Train or a drive up the Silverado Trail rather than Highway 29 for the quieter side, and Castello di Amorosa if you want spectacle. Book everything: tastings are appointment-based, not drop-in.

What to do in Napa besides wineries?

Hot-air ballooning at dawn over the valley is the signature non-wine activity. Beyond that: the Oxbow Public Market in Napa town, cycling the flat valley floor, the geothermal spas at Calistoga with mud baths and geysers, and hiking in Bothe-Napa Valley State Park. The food scene alone justifies a day.

Is it better to stay in Napa or Sonoma?

Napa is more polished and more expensive, with the marquee names and shorter drives between them. Sonoma is larger, more rural and lower-key, with smaller family wineries and lower tasting fees. Napa suits a first visit and a tighter schedule; Sonoma suits repeat visitors who want less structure and more space.

Frequently asked questions about visiting Napa

When is the best time to visit Napa?

May is the highest-scoring month (10/10 on the Holiday Climate Index). Typical conditions: 10–25°C (3 rainy days). The top three months by score are May, April, October.

What is the worst time to visit Napa?

December is the lowest-scoring month (6/10). Typical conditions: 5–14°C (12 rainy days).

Is Napa too hot in summer?

2 months (July, August) trip the heat deal-breaker in our scoring: apparent temperature crosses the comfort cap, so even with clear skies and low rain the score is held down. Plan around it if heat tolerance is low.

When are crowds lowest in Napa?

Search-interest seasonality (Google Trends 2021-2025) is lowest in December and peaks in July. Interest tracks both in-trip visitors and lead-time planners, so treat it as a "destination is on people's minds" signal rather than literal arrivals.

Which months in Napa have good weather but fewer tourists?

April (climate 10/10, crowd index 49) and October (climate 10/10, crowd index 29) — shoulder months with above-average climate and below-median search-interest. Often the best value-for-weather trade.

What is the UV index in Napa by month?

UV peaks at 10 (very high) in July and is lowest in December at 2 (low). Monthly peak values: Jan 2, Feb 3, Mar 4, Apr 6, May 8, Jun 9, Jul 10, Aug 9, Sep 6, Oct 4, Nov 2, Dec 2. June, July, August reach very high or extreme levels — apply SPF 50+, wear a hat and protective clothing, and limit direct sun between 11:00 and 17:00.

What is the UV index in Napa in July?

July is the peak UV month in Napa, with a daily-peak UV index of 10 (very high). At this level, sunburn can occur in under 20 minutes on unprotected fair skin. Apply SPF 50+, wear protective clothing and a hat, and avoid direct midday sun (11:00–17:00).

How high can UV get in Napa on the sunniest days?

Most days look like the monthly average, but on the sunniest ~1 in 10 days UV climbs higher than the mean suggests. May is the worst case: typical days average UV 8 (high), but the top 10% of days reach UV 9 (very high) — and even higher. Months where the sunniest days routinely exceed the typical reading: February, March, April, May, November. Plan sun protection for the worst case, not the average.

Is air quality in Napa bad for travelers?

PM2.5 (fine-particle pollution) exceeds the WHO sensitive-group guideline (15 µg/m³) in 1 month: December. The worst month is December with a typical-day mean of 9 µg/m³ (fair); on the worst 10% of days PM2.5 reaches 18 µg/m³ (unhealthy for sensitive) and higher. People with asthma, heart conditions, or sensitive children may want to avoid these months or limit outdoor activity. Source: CAMS via Open-Meteo.