Annual mean 11°C · wettest around December · prevailing wind W
Warmest
20.7 °C
Coldest
4.7 °C
Wettest
23%
Windiest
7.2 m/s
Prevailing
W
5.8 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 Grantham over the whole year is 11°C. July is the hottest month, with highs of about 20°C; January is the coldest, with lows of about 3°C. Grantham has no sharply defined rainy season: the chance of rain on a given day runs from 11% in April, the driest month, to 18% in December, the wettest. Winds in Grantham are highest in February, averaging 5.8 m/s (21 km/h), and lightest in May, at 4.4 m/s (16 km/h). The prevailing wind is from the W. The clearest skies in Grantham come in April, when the sky is typically 57% covered; December is the cloudiest month, at 71%.
Month by month Grantham 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
5°C
3°C
-0°C
15%
66%
5.5 m/s
0
0
5
February
8°C
4°C
1°C
17%
65%
5.8 m/s
0
0
14
March
9°C
5°C
4°C
16%
65%
5.3 m/s
1
0
29
April
12°C
6°C
7°C
11%
57%
4.7 m/s
8
0
48
May
16°C
10°C
12°C
12%
57%
4.4 m/s
28
0
77
June
19°C
13°C
15°C
15%
60%
4.5 m/s
51
5
78
July
20°C
15°C
17°C
14%
62%
4.4 m/s
68
9
78
August
20°C
14°C
17°C
12%
60%
4.6 m/s
67
7
80
September
18°C
12°C
14°C
13%
63%
4.4 m/s
45
5
79
October
14°C
9°C
9°C
16%
66%
4.9 m/s
10
0
69
November
9°C
6°C
4°C
15%
66%
5.1 m/s
0
0
31
December
7°C
5°C
2°C
18%
71%
5.5 m/s
0
0
12
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 Grantham weather by season
Year round, Grantham has days of about 5°C at their warmest in January, its coolest month, and 20°C in July, 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 11°C around the clock. Rain is most likely around December and least likely around April. 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.
Grantham weather in winterDecember to February
High 7°CLow 4°CRain 17%
Winter in Grantham has typical daily highs of about 7°C and lows of about 4°C, with a 17% chance of rain on a given day.
Grantham weather in springMarch to May
High 12°CLow 7°CRain 13%
Spring in Grantham has typical daily highs of about 12°C and lows of about 7°C, with a 13% chance of rain on a given day.
Grantham weather in summerJune to August
High 20°CLow 14°CRain 13%
Summer in Grantham has typical daily highs of about 20°C and lows of about 14°C, with a 13% chance of rain on a given day.
Grantham weather in autumnSeptember to November
High 13°CLow 9°CRain 15%
Autumn in Grantham has typical daily highs of about 13°C and lows of about 9°C, with a 15% chance of rain on a given day.
When is the rainy season in Grantham?
Grantham has no sharply defined rainy season: the chance of rain on a given day runs from 11% in April, the driest month, to 18% in December, the wettest.
What time of year is Grantham windiest?
Winds in Grantham are highest in February, averaging 5.8 m/s (21 km/h), and lightest in May, at 4.4 m/s (16 km/h). The prevailing wind is from the W.
What is the average temperature in Grantham year round?
The average temperature in Grantham over the whole year is 11°C. July is the hottest month, with highs of about 20°C; January is the coldest, with lows of about 3°C.