The temperatures in Grantham in August are comfortable with low of 13°C and and high up to 21°C.
You can expect about 3 to 8 days of rain in Grantham during the month of August. It’s a good idea to bring along your umbrella so that you don’t get caught in poor weather.
Our weather forecast can give you a great sense of what weather to expect in Grantham in August 2025.
If you’re planning to visit Grantham in the near future, we highly recommend that you review the 14 day weather forecast for Grantham before you arrive.
Temperatures
21° / 13°
Rainy Days
5
Snowy Days
0
Dry Days
26
Rainfall
65
mm
Sun Hours
4.2
Hrs
