Live Weather & Forecast

Weather in St. Helena

California, United States · Real-time conditions & 3-day outlook

Flag of United States
Light rain
11°C
Feels like 12°C
52°F / Feels 53°F
Light rain
St. Helena, California
🌙 Nighttime
Updated: 2026-04-13 01:45
💧
Humidity
89%
💨
Wind
3.6 km/h NE
🌬️
Wind Gust
3.8 km/h
🌡️
Pressure
1018 mb
👁️
Visibility
16 km
☀️
UV Index
0 (Low)
🌧️
Precipitation
0 mm
☁️
Cloud Cover
100%
💦
Dew Point
7.8°C
🌐
Wind Degree
47°

Air Quality Index

US EPA: Good UK DEFRA: Low (1)
CO
187.9 μg/m³
NO₂
8.4 μg/m³
O₃
27 μg/m³
SO₂
1.6 μg/m³
PM 2.5
8.3 μg/m³
PM 10
9.5 μg/m³

Weather Alerts 2

Met · Minor · Expected
Frost Advisory issued April 12 at 12:24PM PDT until April 13 at 8:00AM PDT by NWS Eureka CA

* WHAT...Temperatures as low as 33 will result in frost formation. * WHERE...Northern Mendocino Interior, and Northern Lake. * WHEN...From 2 AM to 8 AM PDT Monday. * IMPACTS...Frost could harm sensitive outdoor vegetation. Sensitive outdoor plants may be killed if left uncovered. * ADDITIONAL DETAILS...Some valleys may see fog instead, which will reduce the risk of frost.

Take steps now to protect tender plants from the cold.

Effective: 2026-04-12T12:24:00-07:00  ·  Expires: 2026-04-13T08:00:00-07:00
Met · Minor · Expected
Frost Advisory issued April 12 at 10:32PM PDT until April 13 at 8:00AM PDT by NWS Eureka CA

* WHAT...Temperatures as low as 35 will result in frost formation. * WHERE...Northern Mendocino Interior, and Northern Lake. * WHEN...From 2 AM to 8 AM PDT Monday. * IMPACTS...Frost could harm sensitive outdoor vegetation. Sensitive outdoor plants may be killed if left uncovered. * ADDITIONAL DETAILS...Some valleys may see fog instead, which will reduce the risk of frost.

Take steps now to protect tender plants from the cold.

Effective: 2026-04-12T22:32:00-07:00  ·  Expires: 2026-04-13T08:00:00-07:00

Today's Hourly Forecast

24-hour breakdown for St. Helena, California

12 AM
Clear
10°
Clear
💧 88% 💨 0.7 km/h
1 AM
Light rain
11°
Light rain
💧 89% 💨 3.6 km/h
2 AM
Clear
9°
Clear
💧 89% 💨 4 km/h
3 AM
Clear
9°
Clear
💧 84% 💨 4.3 km/h
4 AM
Clear
9°
Clear
💧 82% 💨 5.4 km/h
5 AM
Clear
9°
Clear
💧 79% 💨 4.7 km/h
6 AM
Overcast
9°
Overcast
💧 80% 💨 4.7 km/h
7 AM
Cloudy
10°
Cloudy
💧 77% 💨 5 km/h
8 AM
Sunny
11°
Sunny
💧 80% 💨 4 km/h
9 AM
Sunny
12°
Sunny
💧 77% 💨 3.6 km/h
10 AM
Sunny
13°
Sunny
💧 73% 💨 2.9 km/h
11 AM
Sunny
14°
Sunny
💧 67% 💨 2.9 km/h
12 PM
Sunny
15°
Sunny
💧 62% 💨 2.9 km/h
1 PM
Sunny
16°
Sunny
💧 59% 💨 4 km/h
2 PM
Sunny
17°
Sunny
💧 56% 💨 6.5 km/h
3 PM
Sunny
17°
Sunny
💧 55% 💨 9.4 km/h
4 PM
Cloudy
15°
Cloudy
💧 59% 💨 11.5 km/h
5 PM
Overcast
15°
Overcast
💧 70% 💨 12.2 km/h
6 PM
Sunny
15°
Sunny
💧 66% 💨 9.4 km/h
7 PM
Sunny
13°
Sunny
💧 71% 💨 5 km/h
8 PM
Partly Cloudy
12°
Partly Cloudy
💧 76% 💨 3.2 km/h
9 PM
Clear
12°
Clear
💧 79% 💨 3.6 km/h
10 PM
Clear
9°
Clear
💧 80% 💨 4.3 km/h
11 PM
Mist
8°
Mist
💧 94% 💨 6.8 km/h

3-Day Forecast

Daily overview for St. Helena, California

Today
Sunny
Sunny
17° / 5°
🌧️ 0% chance of rain
💧 Avg. humidity: 75%
💨 Max wind: 12.2 km/h
🌧️ Total precip: 0 mm
☀️ UV Index: 1.2
🌅 Sunrise: 06:36 AM
🌇 Sunset: 07:45 PM
🌙 Waning Crescent
🌑 Moon: 23% lit
Tue, Apr 14
Mist
Mist
17° / 6°
🌧️ 0% chance of rain
💧 Avg. humidity: 85%
💨 Max wind: 15.1 km/h
🌧️ Total precip: 0 mm
☀️ UV Index: 1.6
🌅 Sunrise: 06:35 AM
🌇 Sunset: 07:46 PM
🌙 Waning Crescent
🌑 Moon: 15% lit
Wed, Apr 15
Partly Cloudy
Partly Cloudy
14° / 5°
🌧️ 0% chance of rain
💧 Avg. humidity: 85%
💨 Max wind: 18 km/h
🌧️ Total precip: 0 mm
☀️ UV Index: 1.5
🌅 Sunrise: 06:33 AM
🌇 Sunset: 07:47 PM
🌙 Waning Crescent
🌑 Moon: 8% lit

Best Time to Visit St. Helena

Plan your trip to St. Helena, United States around the most favorable weather conditions.

Peak Season
June – September
Warm, dry summers — ideal for outdoor activities.
Shoulder Season
April – May, October
Fewer crowds, moderate prices, mild weather.
Off Season
November – March
Cooler temperatures; some regions may experience rain or snow.
← Back to St. Helena 🗓 View Holidays 2026

Frequently Asked Questions

What is the current weather in St. Helena?
Current conditions in St. Helena: Light rain, temperature 11°C, humidity 89%.
What is the best time to visit St. Helena?
The best time to visit St. Helena is typically June – September. Warm, dry summers — ideal for outdoor activities.
What is the climate like in St. Helena?
St. Helena is located at approximately 38.5° latitude. It has a temperate climate with warm summers and cold winters.
Does it rain a lot in St. Helena?
The wettest period in St. Helena is typically during November – March. Cooler temperatures; some regions may experience rain or snow.
What should I pack for a trip to St. Helena?
For visits to St. Helena during June – September: light clothing and sun protection. For November – March: layers and a waterproof jacket are recommended.
What country is St. Helena in?
St. Helena is located in United States, in the state of California.
What are the public holidays in St. Helena in 2026?
View the 2026 public holidays for St. Helena on our Holidays page.
What are the GPS coordinates used for the weather forecast in St. Helena?
The weather forecast for St. Helena uses coordinates 38.5052, -122.47.