Days 1-14 are a real forecast from global weather models. Days 15-30 are season-typical values based on climate normals 1991-2020 (MET) — good for planning, NOT an exact forecast that far ahead.
The forecast for Tønsberg and the places around it comes from the same weather models as the place pages. Radar: RainViewer, images from the last two hours.
30 days — Tønsberg
14 real + 16 synthesised
Mon · Today Clear
+11°+7°7%
Tue · Tomorrow Clear
+10°+6°2,1 mm
Wednesday 21/10 Light rain
+12°+8°22,8 mm
Thursday 22/10 Light rain
+11°+10°28,5 mm
Friday 23/10 Showers
+11°+10°5,2 mm
Saturday 24/10 Showers
+11°+9°5,7 mm
Sunday 25/10 Rain
+10°+8°31,7 mm
Monday 26/10 Clear
+10°+8°0,3 mm
Tuesday 27/10 Showers
+13°+8°6,5 mm
Wednesday 28/10 Showers
+12°+10°4,1 mm
Thursday 29/10 Cloudy
+11°+9°4,3 mm
Friday 30/10 Showers
+10°+8°6,0 mm
Saturday 31/10 Clear
+9°+6°5%
Sunday 1/11 Showers
+11°+7°5,2 mm
Monday 2/11 Rain (climate normal)
+5°0°9,2 mm
Tuesday 3/11 Partly cloudy (climate normal)
+5°+1°20%
Wednesday 4/11 Partly cloudy (climate normal)
+7°+2°20%
Thursday 5/11 Rain (climate normal)
+4°0°5,4 mm
Friday 6/11 Partly cloudy (climate normal)
+3°-1°20%
Saturday 7/11 Partly cloudy (climate normal)
0°-3°20%
Sunday 8/11 Rain (climate normal)
+1°-2°7,5 mm
Monday 9/11 Partly cloudy (climate normal)
+4°0°20%
Tuesday 10/11 Partly cloudy (climate normal)
+7°+2°20%
Wednesday 11/11 Rain (climate normal)
+5°0°3,9 mm
Thursday 12/11 Partly cloudy (climate normal)
+5°+1°20%
Friday 13/11 Partly cloudy (climate normal)
+4°0°20%
Saturday 14/11 Rain (climate normal)
+2°-2°4,6 mm
Sunday 15/11 Partly cloudy (climate normal)
+1°-2°20%
Monday 16/11 Partly cloudy (climate normal)
+2°-1°20%
Tuesday 17/11 Rain (climate normal)
+4°0°8,8 mm
How does the long-range forecast work?
Days 1-14: Fetched live from global weather models (ECMWF, GFS) with statistical correction. Reliability about 85 % for days 1-3, about 60 % for days 7-10, about 45 % for days 11-14.
Days 15-30: A real forecast does not exist that far ahead (chaotic system). Instead we show season-typical values: the monthly average Tmax/Tmin from climate normals 1991-2020, with mild weekly variation.
Use: «About how warm is it usually in Oslo the last week of July?» — a good question for days 15-30. «Will it rain on 27 May?» — no serious forecast can answer that.