Days 1-14 are a real forecast from global weather models. Days 15-30 are season-typical values based on Météo-France climate normals 1991-2020 — good for planning, NOT an exact forecast that far ahead.
30 days — Nantes
14 real + 16 synthesised
Fri · Today Clear
+27°+12°6%
Sat · Tomorrow Clear
+32°+12°3%
Sunday 14/6 Clear
+31°+14°3%
Monday 15/6 Clear
+30°+13°1%
Tuesday 16/6 Clear
+33°+14°2%
Wednesday 17/6 Clear
+36°+18°1%
Thursday 18/6 Partly cloudy
+34°+17°0,1 mm
Friday 19/6 Partly cloudy
+24°+14°17%
Saturday 20/6 Clear
+29°+11°2%
Sunday 21/6 Partly cloudy
+35°+18°0,2 mm
Monday 22/6 Showers
+26°+15°0,8 mm
Tuesday 23/6 Partly cloudy
+24°+14°17%
Wednesday 24/6 Clear
+30°+12°3%
Thursday 25/6 Clear
+32°+12°1%
Friday 26/6 Rain (climate normal)
+22°+12°2,7 mm
Saturday 27/6 Partly cloudy (climate normal)
+23°+13°20%
Sunday 28/6 Partly cloudy (climate normal)
+23°+13°20%
Monday 29/6 Rain (climate normal)
+22°+12°4,1 mm
Tuesday 30/6 Partly cloudy (climate normal)
+22°+12°20%
Wednesday 1/7 Partly cloudy (climate normal)
+23°+13°20%
Thursday 2/7 Rain (climate normal)
+22°+12°2,3 mm
Friday 3/7 Partly cloudy (climate normal)
+24°+13°20%
Saturday 4/7 Partly cloudy (climate normal)
+28°+16°20%
Sunday 5/7 Rain (climate normal)
+28°+16°4,5 mm
Monday 6/7 Partly cloudy (climate normal)
+27°+15°20%
Tuesday 7/7 Partly cloudy (climate normal)
+23°+13°20%
Wednesday 8/7 Rain (climate normal)
+23°+13°2,3 mm
Thursday 9/7 Partly cloudy (climate normal)
+22°+12°20%
Friday 10/7 Partly cloudy (climate normal)
+25°+14°20%
Saturday 11/7 Rain (climate normal)
+28°+16°4,1 mm
How does the long-range forecast work?
Days 1-14: Fetched live from global weather models (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 Tmax/Tmin from Météo-France climate normals 1991-2020 directly for Nantes, with mild weekly variation.
Use: "Roughly how warm is it usually in Paris in the last week of July?" — a good question for days 15-30. "Will it rain on 27 May?" — no serious forecast can say.
Official weather data from Météo-France (French Meteorological and Hydrological Institute) · Météo-France · French Museum of Natural History · Bison Futé