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Nerd mode: every forecast, readouts, filters and range & bearing for weather enthusiasts

This week’s weatherTrondheim, Norway

Rain is likely in Trondheim on Saturday

7 in 10 of NOAA’s 31 GEFS forecasts bring measurable rain to Trondheim Sat 2–8 p.m. CEST; 2 in 10 bring 2.5 mm or more Sat 8 p.m.–2 a.m.

NOAA GEFS, 31 forecasts · Mon 28 Sep 18Z run · updated Tues., Sept. 29, 1:03 a.m. CEST · times are Trondheim’s (CEST)

See it on the globe For warnings, follow your national weather service.

Quick answers

Will it rain in Trondheim this week?
The best chances of measurable rain: Tuesday (3 in 10 forecasts, 2–8 a.m.); Friday (4 in 10 forecasts, 8 a.m.–2 p.m.); Saturday (7 in 10 forecasts, 2–8 p.m.); Sunday, Oct. 4 (7 in 10 forecasts, 8 p.m.–2 a.m.). Drier: Wed, Thu (fewer than 2 in 10 forecasts in any six hours). Times are CEST.
How much rain will Trondheim get this week?
By Mon., Oct. 5, 8 p.m. CEST (the end of the forecast), the middle forecast has 12 mm of rain and melted snow, counting from Tue 2 a.m. 5 in 10 forecasts bring 13 mm or more in total.
How windy will it get in Trondheim?
Gusts over 48 km/h: 7 in 10 forecasts at Thu 2 a.m. CEST. The middle forecast’s strongest gust is 52 km/h, Wed 8 p.m. Checked every six hours, so a brief peak can fall between.
How warm or cold will it be in Trondheim?
At the six-hourly times, the middle forecast runs from 6°C (Tue 8 a.m.) to 16°C (Thu 2 p.m.) CEST. The day’s real high and low can fall between those times.
Are any storms heading for Trondheim?
No storm Stormlines tracks has 1 in 10 forecasts passing its centre within 160 kilometres of Trondheim this week.

Chance of rain, six hours at a time

Tue 2–8 a.m.: 3 in 10 forecasts with measurable rain; middle forecast almost noneTue 8 a.m.–2 p.m.: fewer than 1 in 10 forecasts with measurable rain; middle forecast almost noneTue 2–8 p.m.: fewer than 1 in 10 forecasts with measurable rain; middle forecast almost noneTue 8 p.m.–2 a.m.: fewer than 1 in 10 forecasts with measurable rain; middle forecast almost noneWed 2–8 a.m.: fewer than 1 in 10 forecasts with measurable rain; middle forecast almost noneWed 8 a.m.–2 p.m.: fewer than 1 in 10 forecasts with measurable rain; middle forecast almost noneWed 2–8 p.m.: fewer than 1 in 10 forecasts with measurable rain; middle forecast almost noneWed 8 p.m.–2 a.m.: fewer than 1 in 10 forecasts with measurable rain; middle forecast almost noneThu 2–8 a.m.: fewer than 1 in 10 forecasts with measurable rain; middle forecast almost noneThu 8 a.m.–2 p.m.: fewer than 1 in 10 forecasts with measurable rain; middle forecast almost noneThu 2–8 p.m.: fewer than 1 in 10 forecasts with measurable rain; middle forecast almost noneThu 8 p.m.–2 a.m.: fewer than 1 in 10 forecasts with measurable rain; middle forecast almost noneFri 2–8 a.m.: 3 in 10 forecasts with measurable rain; middle forecast almost noneFri 8 a.m.–2 p.m.: 4 in 10 forecasts with measurable rain; middle forecast almost noneFri 2–8 p.m.: 4 in 10 forecasts with measurable rain; middle forecast almost noneFri 8 p.m.–2 a.m.: 1 in 10 forecasts with measurable rain; middle forecast almost noneSat 2–8 a.m.: 2 in 10 forecasts with measurable rain; middle forecast almost noneSat 8 a.m.–2 p.m.: 4 in 10 forecasts with measurable rain; middle forecast almost noneSat 2–8 p.m.: 7 in 10 forecasts with measurable rain; middle forecast 0.6 mmSat 8 p.m.–2 a.m.: 6 in 10 forecasts with measurable rain; middle forecast 0.4 mmSun 2–8 a.m.: 3 in 10 forecasts with measurable rain; middle forecast almost noneSun 8 a.m.–2 p.m.: 3 in 10 forecasts with measurable rain; middle forecast almost noneSun 2–8 p.m.: 6 in 10 forecasts with measurable rain; middle forecast 0.6 mmSun 8 p.m.–2 a.m.: 7 in 10 forecasts with measurable rain; middle forecast 0.7 mmMon 2–8 a.m.: 8 in 10 forecasts with measurable rain; middle forecast 0.8 mmMon 8 a.m.–2 p.m.: 9 in 10 forecasts with measurable rain; middle forecast 1.2 mmMon 2–8 p.m.: 8 in 10 forecasts with measurable rain; middle forecast 1.1 mm

Each bar is the share of the 31 forecasts with measurable rain or melted snow in that six hours; the darker the bar, the more forecasts agree. Local days, CEST.

The week, day by day

DayChance of rain2.5 mm or moreTotal by day’s endStrongest gustTemperature
Tue 293 in 10<1 in 10almost none · <1 in 1014 km/h6°C–13°C
Wed 30<1 in 10<1 in 10almost none · <1 in 1052 km/h7°C–15°C
Thu 1<1 in 10<1 in 10almost none · <1 in 1051 km/h11°C–16°C
Fri 24 in 102 in 101.7 mm · <1 in 1012 km/h9°C–13°C
Sat 37 in 102 in 105.3 mm · 1 in 1013 km/h7°C–12°C
Sun 47 in 102 in 108.4 mm · 2 in 1023 km/h6°C–11°C
Mon 5 (part)9 in 103 in 1012 mm · 5 in 1030 km/h8°C–10°C

Chances are the highest in any six hours of the day. “Total by day’s end” is the middle forecast’s running total since Tue 2 a.m., and the share of forecasts with 13 mm or more by then; totals aren’t added up day by day, because the middle forecast of each day isn’t the same forecast. Gusts and temperatures are read every six hours.

Storms near Trondheim

No storm Stormlines tracks has 1 in 10 forecasts passing its centre near Trondheim this week. Every storm we’re tracking →

About these numbers

They come from one source, NOAA’s Global Ensemble Forecast System (GEFS): 31 runs of the same model, each started slightly differently, read at Trondheim’s coordinates on a grid about 55 km (35 miles) apart. “8 in 10 forecasts” means 8 in 10 of those runs. Nothing is adjusted for local effects such as coasts, lakes, hills or city heat, so the numbers can differ from your local official forecast, especially for snow and showers.

“Measurable rain” counts rain or melted snow in a six-hour period. Not an official forecast: follow your national weather service for warnings and decisions. How the forecasts are read: how to read the maps and the glossary.

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