Days 1-16 are a real forecast from global weather models. Days 17-30 are season-typical values based on DWD climate normals 1991-2020 — good for planning, NOT an exact forecast that far ahead.
30 days — Mainz
14 real + 16 synthesised
Thu · Today Clear
+29°+20°1%
Fri · Tomorrow Clear
+27°+16°1%
Saturday 8/8 Clear
+30°+17°1%
Sunday 9/8 Clear
+34°+19°1%
Monday 10/8 Clear
+38°+21°2%
Tuesday 11/8 Clear
+32°+22°1%
Wednesday 12/8 Clear
+30°+19°1%
Thursday 13/8 Clear
+32°+19°1%
Friday 14/8 Clear
+36°+22°1%
Saturday 15/8 Clear
+38°+24°4,9 mm
Sunday 16/8 Showers
+24°+19°3,8 mm
Monday 17/8 Partly cloudy
+22°+17°5%
Tuesday 18/8 Clear
+24°+14°5%
Wednesday 19/8 Clear
+20°+14°0,2 mm
Thursday 20/8 Rain
+26°+16°0,6 mm
Friday 21/8 Heavy rain
+26°+16°1,2 mm
Saturday 22/8 Partly cloudy (climate normal)
+27°+15°20%
Sunday 23/8 Rain (climate normal)
+26°+14°5,7 mm
Monday 24/8 Partly cloudy (climate normal)
+24°+13°20%
Tuesday 25/8 Partly cloudy (climate normal)
+24°+13°20%
Wednesday 26/8 Rain (climate normal)
+23°+12°5,9 mm
Thursday 27/8 Partly cloudy (climate normal)
+27°+14°20%
Friday 28/8 Partly cloudy (climate normal)
+28°+15°20%
Saturday 29/8 Rain (climate normal)
+27°+15°5,5 mm
Sunday 30/8 Partly cloudy (climate normal)
+27°+14°20%
Monday 31/8 Partly cloudy (climate normal)
+26°+14°20%
Tuesday 1/9 Rain (climate normal)
+19°+10°2,5 mm
Wednesday 2/9 Partly cloudy (climate normal)
+19°+10°20%
Thursday 3/9 Partly cloudy (climate normal)
+21°+11°20%
Friday 4/9 Rain (climate normal)
+25°+13°2,7 mm
Long-range forecast · Mainz
Mainz — 30-day analysis
Across the 30-day trend for Mainz, highs and lows span 10° to 38°, cooling down later in the month. The first 16 days are a real forecast, with rain on about 3 of them; the rest is based on the 1991–2020 climate normals.
How does the long-range forecast work?
Days 1-16 are a real forecast from global models (ICON, ECMWF, GFS): days 1-3 are almost always right, uncertainty grows afterwards, and from day 11 these are tendencies rather than exact values.
From day 17 a serious day-by-day forecast is physically impossible. We therefore show the 1991-2020 climate normals (monthly mean Tmax/Tmin) directly for Mainz, with mild weekly variation — the typical weather for the season, not a daily prediction.
Rule of thumb: good for “how warm is it usually in late July?”, not for “will it rain on the 27th?”.