Days 1-14 are a real forecast from weather models. Days 15-30 are season-typical values based on 1991-2020 climate averages — good for planning, NOT an exact forecast that far ahead.
30 days — Cambridge
14 real + 16 synthesised
Wed · Today Sunny
34°17°2%
Thu · Tomorrow Sunny
28°16°3%
Friday 31/7 Sunny
25°11°1%
Saturday 1/8 Sunny
26°13°2%
Sunday 2/8 Sunny intervals
28°11°3%
Monday 3/8 Sunny intervals
27°14°5%
Tuesday 4/8 Sunny intervals
20°13°0.1 mm
Wednesday 5/8 Sunny
24°9°4%
Thursday 6/8 Sunny
24°12°4%
Friday 7/8 Sunny
24°12°3%
Saturday 8/8 Sunny
25°10°3%
Sunday 9/8 Sunny
26°11°2%
Monday 10/8 Sunny intervals
30°13°3%
Tuesday 11/8 Sunny
32°16°1%
Wednesday 12/8 Rain (climate average)
28°19°7.0 mm
Thursday 13/8 Sunny intervals (climate average)
31°20°20%
Friday 14/8 Sunny intervals (climate average)
31°21°20%
Saturday 15/8 Rain (climate average)
30°20°6.6 mm
Sunday 16/8 Sunny intervals (climate average)
28°18°20%
Monday 17/8 Sunny intervals (climate average)
26°18°20%
Tuesday 18/8 Rain (climate average)
28°19°6.6 mm
Wednesday 19/8 Sunny intervals (climate average)
28°19°20%
Thursday 20/8 Sunny intervals (climate average)
30°20°20%
Friday 21/8 Rain (climate average)
32°21°8.1 mm
Saturday 22/8 Sunny intervals (climate average)
30°20°20%
Sunday 23/8 Sunny intervals (climate average)
27°18°20%
Monday 24/8 Rain (climate average)
27°18°5.7 mm
Tuesday 25/8 Sunny intervals (climate average)
27°18°20%
Wednesday 26/8 Sunny intervals (climate average)
30°20°20%
Thursday 27/8 Rain (climate average)
32°21°6.2 mm
How does the long-range forecast work?
Days 1-14: Fetched live from weather models (UKV, ECMWF, GFS) with statistical correction. Reliability ~85% for days 1-3, ~60% for days 7-10, ~45% for days 11-14.
Days 15-30: A real forecast does not exist that far ahead (a chaotic system). Instead we show season-typical values: the month’s average max/min from 1991-2020 climate data (London baseline with latitude correction for Cambridge), with mild weekly variation.
Use: "Roughly how warm is it usually in London in the last week of July?" — a good question for days 15-30. "Will it rain on 27 May?" — no serious forecast can say.
Forecasts from the UK Met Office UKV model, global weather models and official UK environmental data · Met Office UKV model · Environment Agency · Copernicus CAMS · NOAA