Annual mean 13°C · wettest around January · prevailing wind NW
Warmest
30.4 °C
Coldest
3.1 °C
Wettest
37%
Windiest
4.0 m/s
Prevailing
NW
3.1 m/s average
When this place is good five ratings · thirty-six ten-day sections · click a cell to read it
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 Iiyama over the whole year is 13°C. August is the hottest month, with highs of about 29°C; January is the coldest, with lows of about -1°C. Iiyama has no sharply defined rainy season: the chance of rain on a given day runs from 16% in May, the driest month, to 30% in January, the wettest. Winds in Iiyama are highest in April, averaging 2.9 m/s (10 km/h), and lightest in July, at 2.2 m/s (8 km/h). The prevailing wind is from the NW. The clearest skies in Iiyama come in November, when the sky is typically 61% covered; September is the cloudiest month, at 79%.
Month by month Iiyama 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
4°C
-1°C
-1°C
30%
62%
2.7 m/s
0
0
8
February
5°C
-1°C
-0°C
25%
63%
2.7 m/s
0
0
12
March
10°C
3°C
5°C
21%
63%
2.7 m/s
7
0
40
April
15°C
8°C
12°C
18%
66%
2.9 m/s
31
1
70
May
20°C
13°C
18°C
16%
68%
2.6 m/s
71
10
72
June
24°C
18°C
23°C
20%
75%
2.4 m/s
69
39
41
July
28°C
22°C
30°C
24%
76%
2.2 m/s
25
53
7
August
29°C
23°C
32°C
18%
73%
2.2 m/s
18
48
5
September
25°C
19°C
26°C
22%
79%
2.2 m/s
53
45
27
October
18°C
13°C
17°C
20%
72%
2.3 m/s
59
11
70
November
13°C
7°C
10°C
20%
61%
2.5 m/s
22
0
64
December
6°C
2°C
2°C
28%
61%
2.7 m/s
1
0
21
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 Iiyama weather by season
Year round, Iiyama has days of about 4°C at their warmest in January, its coolest month, and 29°C in August, its warmest; the coolest hours of the day run from -1°C to 23°C through the year, and the average temperature over the year is 13°C around the clock. Rain is most likely around January and least likely around May. 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.
Iiyama weather in winterDecember to February
High 5°CLow 0°CRain 28%
Winter in Iiyama has typical daily highs of about 5°C and lows of about 0°C, with a 28% chance of rain on a given day.
Iiyama weather in springMarch to May
High 15°CLow 8°CRain 18%
Spring in Iiyama has typical daily highs of about 15°C and lows of about 8°C, with a 18% chance of rain on a given day.
Iiyama weather in summerJune to August
High 27°CLow 21°CRain 21%
Summer in Iiyama has typical daily highs of about 27°C and lows of about 21°C, with a 21% chance of rain on a given day.
Iiyama weather in autumnSeptember to November
High 19°CLow 13°CRain 21%
Autumn in Iiyama has typical daily highs of about 19°C and lows of about 13°C, with a 21% chance of rain on a given day.
When is the rainy season in Iiyama?
Iiyama has no sharply defined rainy season: the chance of rain on a given day runs from 16% in May, the driest month, to 30% in January, the wettest.
What time of year is Iiyama windiest?
Winds in Iiyama are highest in April, averaging 2.9 m/s (10 km/h), and lightest in July, at 2.2 m/s (8 km/h). The prevailing wind is from the NW.
What is the average temperature in Iiyama year round?
The average temperature in Iiyama over the whole year is 13°C. August is the hottest month, with highs of about 29°C; January is the coldest, with lows of about -1°C.