Sonoma, United States experiences average highs of 23°C (73°F) and lows of 10°C (50°F) throughout the year. The climate is relatively dry, with only 5 rainy days per month on average. Sunshine is abundant, averaging about 10 hours per day. Average highs have stayed broadly stable across the available records.
Sonoma, United States Weather & Climate 2026
Monthly climate averages for Sonoma, United States. Based on 10-year ERA5 reanalysis data.
Climate Overview
Drier season: May–Oct 
Wetter season: Jan–Dec At-a-Glance Climate Summary
Live Weather & Air Quality
Key figures
Climate Score
8.1/10
Best: May, June, July, August, September
UV Index
6
High
Temperature 23°C / 10°C
Feels Like 22°C / 9°C
Rainy Days 5
Rainfall 52 mm
Sunshine 10 h
Humidity 68%
Wind Speed 14 km/h
Dew Point 11°C
Hottest Month
30°C
August
Avg Low15°C
Rain0days
Coldest Month
6°C
January
Avg High15°C
Rain10days
Driest Month
0days
June
Avg High29°C
Avg Low14°C
Windiest Month
17 km/h
May (Gusts 45)
Sea Temperature
11°C – 23°C
Warmest water: August (
22.8°C
)
Worst Time to Visit
Consider avoiding January, February, December due to less favorable weather conditions.
Sun Position
Sunrise 05:47
Daylight 14.8h
Sunset 20:36
Live conditions—
Sonoma on the map · live conditions
Sonoma, United States
- Continent
- Americas
- Country
- United States
- City
- Sonoma
- Population
- 11K
- Elevation
- 26 m
- Coordinates
- 38.29°, -122.46°
Seasonal Breakdown
Spring
Mar–May
Avg High 21°C
Avg Low 9°C
Rain 6 days/mo
1/3 best months
Summer
Jun–Aug
Avg High 30°C
Avg Low 15°C
Rain 0 days/mo
3/3 best months
Autumn
Sep–Nov
Avg High 25°C
Avg Low 12°C
Rain 3 days/mo
1/3 best months
Winter
Dec–Feb
Avg High 16°C
Avg Low 6°C
Rain 9 days/mo
Climate Charts
Based on historical averages (2016–2025)
Monthly Temperatures
HighLowShaded bands show the typical range across the available yearly records.
Line chart showing monthly temperatures. Jan: 15°C / 6°C . Feb: 17°C / 6°C . Mar: 17°C / 7°C . Apr: 21°C / 9°C . May: 25°C / 11°C . Jun: 29°C / 14°C . Jul: 30°C / 15°C . Aug: 30°C / 15°C . Sep: 29°C / 15°C . Oct: 26°C / 13°C . Nov: 19°C / 8°C . Dec: 15°C / 6°C .
Monthly Rainfall
Rainfall
Bar chart showing monthly rainfall. Jan: 138 mm. Feb: 116 mm. Mar: 107 mm. Apr: 29 mm. May: 17 mm. Jun: 1 mm. Jul: 0 mm. Aug: 0 mm. Sep: 4 mm. Oct: 33 mm. Nov: 65 mm. Dec: 112 mm.
Monthly Humidity
Humidity
Line chart showing monthly humidity. Jan: 81%. Feb: 74%. Mar: 75%. Apr: 70%. May: 64%. Jun: 57%. Jul: 60%. Aug: 62%. Sep: 62%. Oct: 61%. Nov: 72%. Dec: 81%.
Monthly Wind Speed
Wind SpeedGusts
Bar chart showing monthly wind speed. Jan: 13 km/h . Feb: 15 km/h . Mar: 16 km/h . Apr: 16 km/h . May: 17 km/h . Jun: 17 km/h . Jul: 15 km/h . Aug: 15 km/h . Sep: 14 km/h . Oct: 12 km/h . Nov: 11 km/h . Dec: 12 km/h .
Sunshine
Sunshine
Sunshine: Jan: 6h. Feb: 8h. Mar: 9h. Apr: 11h. May: 13h. Jun: 13h. Jul: 13h. Aug: 12h. Sep: 11h. Oct: 9h. Nov: 8h. Dec: 6h.
Sea Temperature
Sea Temperatureswim
Line chart showing monthly sea temperature. Jan: 11°C . Feb: 12°C . Mar: 13°C . Apr: 17°C . May: 20°C . Jun: 22°C . Jul: 23°C . Aug: 23°C . Sep: 22°C . Oct: 20°C . Nov: 16°C . Dec: 12°C .
UV Index
UV Index
Bar chart showing monthly UV index. Jan: UV 3. Feb: UV 4. Mar: UV 5. Apr: UV 7. May: UV 8. Jun: UV 8. Jul: UV 8. Aug: UV 8. Sep: UV 6. Oct: UV 5. Nov: UV 3. Dec: UV 2.
Monthly Daylight Hours
Daylight12h reference
Monthly Dew Point & Comfort
Dew Point Dry Comfortable Humid Muggy Oppressive
Climate Trends
Average highs have stayed broadly stable across the available records. Average rainfall is trending drier by about 16 mm.
2016 to 2025
Avg high Avg rainfall
Climate summary
| Last 12 months | All years | |
|---|---|---|
| Hottest month | Aug 2025 · 30°C | Aug · 30°C |
| Coldest month | Jan 2025 · 5°C | Jan · 6°C |
| Wettest month | Feb 2025 · 182 mm | Jan · 138 mm |
| Windiest month | May 2025 · 18 km/h | May · 17 km/h |
Month-by-Month Weather Table
January
Fair 
February
Fair March
Good April
Good May best
Excellent June best
Excellent July best
Excellent August best
Excellent September best
Excellent October
Excellent November
Good December
Fair | Month | Temp | Feels Like | Rain | Sun | Humidity | UV | Status | Details |
|---|---|---|---|---|---|---|---|---|
| January | 15°C / 6°C | 13°C / 4°C | 10days (138 mm) Wet | 6.3h Fair | 81% Humid | 2.8 Moderate | Fair | View Details |
| February | 17°C / 6°C | 15°C / 4°C | 7days (116 mm) Good | 8.1h Good | 74% Muggy | 3.5 Moderate | Fair | View Details |
| March | 17°C / 7°C | 16°C / 5°C | 11days (107 mm) Wet | 9.1h Good | 75% Muggy | 5.1 High | Good | View Details |
| April | 21°C / 9°C | 20°C / 8°C | 4days (29 mm) Good | 11h Excellent | 70% Muggy | 6.7 High | Good | View Details |
| May best | 25°C / 11°C | 24°C / 10°C | 2days (17 mm) Excellent | 12.5h Excellent | 64% Muggy | 7.9 Very High | Excellent | View Details |
| June best | 29°C / 14°C | 29°C / 13°C | 0days (1 mm) Excellent | 13.4h Excellent | 57% Moderate | 8.1 Very High | Excellent | View Details |
| July best | 30°C / 15°C | 31°C / 14°C | 0days (0 mm) Excellent | 13.2h Excellent | 60% Moderate | 8.3 Very High | Excellent | View Details |
| August best | 30°C / 15°C | 31°C / 15°C | 0days (0 mm) Excellent | 12.3h Excellent | 62% Muggy | 7.6 Very High | Excellent | View Details |
| September best | 29°C / 15°C | 29°C / 15°C | 1days (4 mm) Excellent | 11.1h Excellent | 62% Muggy | 6.4 High | Excellent | View Details |
| October | 26°C / 13°C | 24°C / 12°C | 3days (33 mm) Excellent | 9.3h Good | 61% Muggy | 4.8 Moderate | Excellent | View Details |
| November | 19°C / 8°C | 18°C / 7°C | 6days (65 mm) Good | 7.8h Good | 72% Muggy | 3.2 Moderate | Good | View Details |
| December | 15°C / 6°C | 14°C / 4°C | 10days (112 mm) Wet | 6.2h Fair | 81% Humid | 2.4 Moderate | Fair | View Details |
Compare Nearby City Climates
Frequently Asked Questions
The best months to visit Sonoma are May, June, July, August, September, when temperatures are comfortable and rainfall is at its lowest. This is based on 10-year climate averages for Sonoma, scoring temperature, rainfall, humidity, and sunshine hours.
The hottest month in Sonoma is August, with average daytime highs of 30°C (87°F). Plan outdoor activities for early morning or late afternoon if visiting during this period.
The coldest month in Sonoma is January, with average overnight lows of 6°C (43°F). Pack warm layers and expect shorter daylight hours during this period.
The wettest month in Sonoma is January, averaging 138mm of precipitation across 10 rainy days. An umbrella or waterproof jacket is essential.
The rainy season in Sonoma runs through March, January, December, with the heaviest rainfall in March. Based on 10-year averages for Sonoma.
Sonoma receives approximately 120 sunshine hours per year. The sunniest month is June with around 13 hours. Based on climate data for Sonoma.
The least favorable months to visit Sonoma are January, February, December, primarily due to less favorable weather conditions. For the best conditions, consider May, June, July, August, September instead.
The annual average UV index in Sonoma is 6, classified as high. Standard sun protection (sunscreen, hat) is recommended during prolonged outdoor exposure.
Average humidity in Sonoma is 68%, classified as moderate. Humidity levels are generally comfortable and should not affect outdoor activities for most people.
Yes — sea temperatures in July, August, September average 23°C (73°F), which is warm and comfortable for swimming and water activities.
Average wind speeds in Sonoma are 14 km/h (9 mph). The windiest month is May with peak winds reaching 17 km/h (10 mph) (gusts up to 45 km/h / 28 mph).
Sonoma averages 10 clear-sky days per month with overall cloud cover around 41%. The clearest skies occur in July.
The annual average dew point in Sonoma is 11°C (52°F), which feels pleasant with low humidity. Outdoor activities are comfortable year-round from a humidity standpoint.
Sonoma has a Hot-Summer Mediterranean climate, classified as Csa under the Köppen system. Temperate climates have mild winters and warm summers, with rainfall spread across the year and four distinct seasons.
The 'feels like' temperature in Sonoma ranges from 9°C (48°F) to 22°C (72°F) on average. The 'feels like' temperature closely matches the actual temperature throughout most of the year.
Yes, June is a great time to visit Sonoma. It earns a climate score of 9.5/10 with Excellent.
For June in Sonoma, pack Breathable clothing, Sunscreen (SPF 30+), Sun hat, Sunglasses, Sandals. With average highs of 29°C (84°F) and 0 rainy days, these essentials will keep you comfortable.
Data Source
Climate data derived from ERA5 reanalysis (ECMWF), averaged over 2016–2025. Sea surface temperature from marine reanalysis data. Climate scores and seasonal estimates are computed by WorldStats.
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