Annual mean 11°C · wettest around December · prevailing wind SW
Warmest
20.2 °C
Coldest
6.1 °C
Wettest
39%
Windiest
5.5 m/s
Prevailing
SW
4.7 m/s average
When this place is good five ratings · thirty-six ten-day sections · click a cell to read it
never good
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 Mountain Ash over the whole year is 11°C. July is the hottest month, with highs of about 19°C; January is the coldest, with lows of about 4°C. Mountain Ash has no sharply defined rainy season: the chance of rain on a given day runs from 20% in July, the driest month, to 35% in December, the wettest. Winds in Mountain Ash are highest in February, averaging 4.7 m/s (17 km/h), and lightest in September, at 3.6 m/s (13 km/h). The prevailing wind is from the SW. The clearest skies in Mountain Ash come in May, when the sky is typically 53% covered; December is the cloudiest month, at 73%.
Month by month Mountain Ash 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
6°C
4°C
2°C
28%
68%
4.1 m/s
0
0
14
February
8°C
5°C
3°C
32%
68%
4.7 m/s
0
0
19
March
9°C
5°C
4°C
31%
66%
4.4 m/s
1
0
31
April
12°C
7°C
7°C
21%
57%
4.1 m/s
6
0
51
May
15°C
10°C
12°C
22%
53%
3.8 m/s
26
0
77
June
18°C
13°C
15°C
21%
59%
4.0 m/s
49
4
79
July
19°C
14°C
17°C
20%
60%
3.7 m/s
67
9
76
August
19°C
14°C
17°C
25%
61%
3.7 m/s
66
4
80
September
17°C
12°C
15°C
27%
61%
3.6 m/s
48
3
79
October
14°C
10°C
11°C
31%
65%
3.9 m/s
15
0
73
November
10°C
7°C
6°C
30%
68%
4.0 m/s
1
0
42
December
8°C
6°C
3°C
35%
73%
4.3 m/s
0
0
23
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 Mountain Ash weather by season
Year round, Mountain Ash has days of about 6°C at their warmest in January, its coolest month, and 19°C in July, its warmest; the coolest hours of the day run from 4°C to 14°C through the year, and the average temperature over the year is 11°C around the clock. Rain is most likely around December and least likely around July. 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.
Mountain Ash weather in winterDecember to February
High 7°CLow 5°CRain 32%
Winter in Mountain Ash has typical daily highs of about 7°C and lows of about 5°C, with a 32% chance of rain on a given day.
Mountain Ash weather in springMarch to May
High 12°CLow 7°CRain 25%
Spring in Mountain Ash has typical daily highs of about 12°C and lows of about 7°C, with a 25% chance of rain on a given day.
Mountain Ash weather in summerJune to August
High 19°CLow 14°CRain 22%
Summer in Mountain Ash has typical daily highs of about 19°C and lows of about 14°C, with a 22% chance of rain on a given day.
Mountain Ash weather in autumnSeptember to November
High 13°CLow 10°CRain 29%
Autumn in Mountain Ash has typical daily highs of about 13°C and lows of about 10°C, with a 29% chance of rain on a given day.
When is the rainy season in Mountain Ash?
Mountain Ash has no sharply defined rainy season: the chance of rain on a given day runs from 20% in July, the driest month, to 35% in December, the wettest.
What time of year is Mountain Ash windiest?
Winds in Mountain Ash are highest in February, averaging 4.7 m/s (17 km/h), and lightest in September, at 3.6 m/s (13 km/h). The prevailing wind is from the SW.
What is the average temperature in Mountain Ash year round?
The average temperature in Mountain Ash over the whole year is 11°C. July is the hottest month, with highs of about 19°C; January is the coldest, with lows of about 4°C.