Annual mean 12°C · wettest around January · prevailing wind SW
Warmest
25.1 °C
Coldest
5.8 °C
Wettest
29%
Windiest
2.7 m/s
Prevailing
SW
2.2 m/s average
When this place is good five ratings · thirty-six ten-day sections · click a cell to read it
never good
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Every reading
bars actual · line feels-like, °Cchance of rain, %wind speed, m/ssky covered, %
The average temperature in St. Helens over the whole year is 12°C. August is the hottest month, with highs of about 26°C; February is the coldest, with lows of about 3°C. The rainy (wet) season in St. Helens runs from October to April, peaking in January with a 33% chance of rain on a given day. The dry season is May to September; August is the driest month, at 11%. Winds in St. Helens are highest in January, averaging 2.1 m/s (8 km/h), and lightest in September, at 1.4 m/s (5 km/h). The prevailing wind is from the SW. The clearest skies in St. Helens come in July, when the sky is typically 32% covered; February is the cloudiest month, at 74%.
Month by month St. Helens climate by month: average temperatures year round · click a month to read it
Month
High
Low
Feels like
Chance of rain
Cloud
Wind
Being outside
Sun
Walking
January
7°C
4°C
3°C
33%
73%
2.1 m/s
0
0
25
February
7°C
3°C
4°C
31%
74%
1.9 m/s
0
0
28
March
10°C
5°C
7°C
28%
65%
1.8 m/s
5
0
50
April
14°C
7°C
11°C
25%
58%
1.8 m/s
21
1
73
May
18°C
10°C
15°C
20%
54%
1.7 m/s
53
7
81
June
21°C
13°C
19°C
19%
48%
1.8 m/s
71
15
73
July
25°C
15°C
23°C
13%
32%
1.8 m/s
83
34
55
August
26°C
15°C
24°C
11%
34%
1.6 m/s
78
40
49
September
21°C
12°C
20°C
19%
46%
1.4 m/s
82
16
72
October
15°C
9°C
13°C
27%
56%
1.4 m/s
38
2
80
November
10°C
6°C
7°C
31%
70%
1.8 m/s
5
0
50
December
7°C
4°C
3°C
31%
74%
1.9 m/s
0
0
22
High and low are the warmest and coolest of four readings a day — midnight, 6am, noon and 6pm — so a true overnight low can sit a degree or two under them. Chance of rain, cloud and wind are the day’s average; feels-like and the three ratings (each out of 100: Good from 55, Ideal from 80) are read at midday.
Seasons, and the year in short St. Helens weather by season
Year round, St. Helens has days of about 7°C at their warmest in December, its coolest month, and 26°C in August, its warmest; the coolest hours of the day run from 3°C to 15°C through the year, and the average temperature over the year is 12°C around the clock. Rain is most likely around January and least likely around August. Every figure here is a decade of observations blended into one representative year, so it reads as what this date is usually like, not a forecast for one particular day.
St. Helens weather in winterDecember to February
High 7°CLow 4°CRain 32%
Winter in St. Helens has typical daily highs of about 7°C and lows of about 4°C, with a 32% chance of rain on a given day.
St. Helens weather in springMarch to May
High 14°CLow 7°CRain 24%
Spring in St. Helens has typical daily highs of about 14°C and lows of about 7°C, with a 24% chance of rain on a given day.
St. Helens weather in summerJune to August
High 24°CLow 14°CRain 14%
Summer in St. Helens has typical daily highs of about 24°C and lows of about 14°C, with a 14% chance of rain on a given day.
St. Helens weather in autumnSeptember to November
High 15°CLow 9°CRain 26%
Autumn in St. Helens has typical daily highs of about 15°C and lows of about 9°C, with a 26% chance of rain on a given day.
When is the rainy season in St. Helens?
The rainy (wet) season in St. Helens runs from October to April, peaking in January with a 33% chance of rain on a given day. The dry season is May to September; August is the driest month, at 11%.
What time of year is St. Helens windiest?
Winds in St. Helens are highest in January, averaging 2.1 m/s (8 km/h), and lightest in September, at 1.4 m/s (5 km/h). The prevailing wind is from the SW.
What is the average temperature in St. Helens year round?
The average temperature in St. Helens over the whole year is 12°C. August is the hottest month, with highs of about 26°C; February is the coldest, with lows of about 3°C.