St Helena, California, United States Climate Change Severity

52
High
The current climate change severity in St Helena is High, with a 3.5% improvement in the climate score compared to last 15 years. This suggests improved conditions, with more favorable environmental indicators and a reduction in negative impacts.
Data: Jan. to Sep. (Historical Vs 2025) - Weather Data Only
Low
020
Moderate
40
High
60
Very High
80
Extreme
100


St Helena Weather Condition Changes (Historic Vs 2025)

0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Historic
2025

Over the past 15 year(s), St Helena temperature has changed by around +0.4%, and has experienced notable climate changes.

Sunny
Cloudy
Rainy
Snowy
Misty
Data: Jan. to Sep. (Historical Vs 2025)

Comparison of Weather Condition (Historic Vs 2025)

HistoricDays

Year 2025Days

Change

sunnySunny
14587
-40%

cloudyCloudy
5685
51.7%

rainyRainy
4845
-6.2%

snowySnowy
00
0%

mistyMisty
015
100%

Disclaimer: Other weather conditions not shown may affect the total day count.

Climate Change Indicators:

Over the past 15 years, St Helena has experienced measurable shifts in key climate parameters, contributing to the current severity score of 52 (within the High severity category). While the score remains High, certain factors have improved over time. Here’s a breakdown of the specific changes observed:

Severity Score

52/100


High

Low
020
Moderate
40
High
60
Very High
80
Extreme
100

From 2010 to 2025, St Helena experienced significant changes:

Temperature change of

+0.07 °C


Variation in annual rainfall

+25.1 %


Change in average humidity

+8.6 %


PM2.5 levels surged by

-77.6 %


Heatwave changed by

-4.5 day(s)


Coldwave changed by

-2.4 day(s)


Wind speeds changed by

+0.2 km/h


These indicators show improvement in key parametes of climate, but St Helena remains in the High severity category. Continuous focus on climate resilience is necessary to avoid further worsening and ensure sustainability.

Check how we calculate Climate Change Severity
Based on data from Jan. to Sep.

St Helena Weather Forecast 30 Days (October - November 2025)
St Helena, California, United States


Condition
Temperature IconTemperature
Humidity Iconhumi.
Wind IconWind Speed
Thu. 23, Oct.
sunnySunny

Temperature Icon27°/11°

Humidity Icon69%

Wind Icon8km/h
Fri. 24, Oct.
mistMist

Temperature Icon20°/7°

Humidity Icon84%

Wind Icon10km/h
Sat. 25, Oct.
moderate rainModerate rain

Temperature Icon16°/11°

Humidity Icon92%

Wind Icon18km/h
Sun. 26, Oct.
overcastOvercast

Temperature Icon15°/10°

Humidity Icon70%

Wind Icon5km/h
Mon. 27, Oct.
sunnySunny

Temperature Icon22°/9°

Humidity Icon67%

Wind Icon8km/h
Tue. 28, Oct.
sunnySunny

Temperature Icon27°/12°

Humidity Icon61%

Wind Icon6km/h
Wed. 29, Oct.
sunnySunny

Temperature Icon29°/13°

Humidity Icon59%

Wind Icon5km/h
Thu. 30, Oct.
partly cloudyPartly Cloudy

Temperature Icon28°/14°

Humidity Icon54%

Wind Icon7km/h
Fri. 31, Oct.
sunnySunny

Temperature Icon29°/13°

Humidity Icon45%

Wind Icon6km/h
Sat. 1, Nov.
sunnySunny

Temperature Icon30°/13°

Humidity Icon44%

Wind Icon5km/h
Sun. 2, Nov.
sunnySunny

Temperature Icon28°/13°

Humidity Icon45%

Wind Icon5km/h
Mon. 3, Nov.
sunnySunny

Temperature Icon26°/10°

Humidity Icon65%

Wind Icon11km/h
Tue. 4, Nov.
sunnySunny

Temperature Icon26°/10°

Humidity Icon61%

Wind Icon6km/h
Wed. 5, Nov.
sunnySunny

Temperature Icon28°/12°

Humidity Icon33%

Wind Icon5km/h
Thu. 6, Nov.
patchy rain possiblePatchy rain possible

Temperature Icon19°/8°

Humidity Icon66%

Wind Icon12km/h
Fri. 7, Nov.
moderate or heavy rain showerModerate or heavy rain shower

Temperature Icon19°/7°

Humidity Icon63%

Wind Icon10km/h
Sat. 8, Nov.
moderate or heavy rain showerModerate or heavy rain shower

Temperature Icon18°/7°

Humidity Icon62%

Wind Icon12km/h
Sun. 9, Nov.
heavy rain at timesHeavy rain at times

Temperature Icon18°/6°

Humidity Icon63%

Wind Icon10km/h
Mon. 10, Nov.
patchy rain possiblePatchy rain possible

Temperature Icon19°/6°

Humidity Icon64%

Wind Icon8km/h
Wed. 12, Nov.
patchy rain possiblePatchy rain possible

Temperature Icon19°/7°

Humidity Icon63%

Wind Icon8km/h
Thu. 13, Nov.
moderate or heavy rain showerModerate or heavy rain shower

Temperature Icon19°/7°

Humidity Icon66%

Wind Icon10km/h
Fri. 14, Nov.
moderate rain at timesModerate rain at times

Temperature Icon19°/7°

Humidity Icon69%

Wind Icon9km/h
Sat. 15, Nov.
moderate or heavy rain showerModerate or heavy rain shower

Temperature Icon18°/7°

Humidity Icon66%

Wind Icon10km/h
Sun. 16, Nov.
moderate or heavy rain showerModerate or heavy rain shower

Temperature Icon18°/7°

Humidity Icon62%

Wind Icon10km/h
Mon. 17, Nov.
moderate or heavy rain showerModerate or heavy rain shower

Temperature Icon18°/7°

Humidity Icon62%

Wind Icon10km/h
Tue. 18, Nov.
moderate or heavy rain showerModerate or heavy rain shower

Temperature Icon16°/6°

Humidity Icon64%

Wind Icon12km/h
Wed. 19, Nov.
moderate or heavy rain showerModerate or heavy rain shower

Temperature Icon15°/6°

Humidity Icon68%

Wind Icon11km/h
Thu. 20, Nov.
moderate or heavy rain showerModerate or heavy rain shower

Temperature Icon15°/6°

Humidity Icon72%

Wind Icon13km/h
Fri. 21, Nov.
moderate or heavy rain showerModerate or heavy rain shower

Temperature Icon16°/6°

Humidity Icon65%

Wind Icon12km/h

Highest & Lowest Weather Forecasts

TemperatureTemperature

High will be onSat. 1, Nov.

29.9°C


Low will be onWed. 19, Nov.

5.6°C

HumidityHumidity

High will be onSat. 25, Oct.

92%


Low will be onWed. 5, Nov.

33%

Wind SpeedWind Speed

High will be onSat. 25, Oct.

18km/h


Low will be onWed. 29, Oct.

5km/h

PrecipitationPrecipitation

High will be onThu. 20, Nov.

15.6mm


Low will be onSun. 26, Oct.

0.05mm

Ultraviolet IndexUV

High will be onTue. 28, Oct.

5


Low will be onThu. 6, Nov.

3