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

This week’s weatherPorto, Portugal

Rain is likely in Porto on Tuesday

Nearly all of NOAA’s 31 GEFS forecasts bring measurable rain to Porto Tue 7 p.m.–1 a.m. WEST; nearly all bring 2.5 mm or more.

NOAA GEFS, 31 forecasts · Mon 28 Sep 18Z run · updated Tues., Sept. 29, 12:03 a.m. WEST · times are Porto’s (WEST)

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

Quick answers

Will it rain in Porto this week?
The best chances of measurable rain: Tuesday (nearly all forecasts, 7 p.m.–1 a.m.); Wednesday (8 in 10 forecasts, 1–7 a.m.); Saturday (4 in 10 forecasts, 7 p.m.–1 a.m.); Sunday, Oct. 4 (7 in 10 forecasts, 1–7 p.m.). Drier: Thu, Fri (fewer than 2 in 10 forecasts in any six hours). Times are WEST.
How much rain will Porto get this week?
By Mon., Oct. 5, 7 p.m. WEST (the end of the forecast), the middle forecast has 33 mm of rain and melted snow, counting from Tue 1 a.m. 8 in 10 forecasts bring 25 mm or more in total; 2 in 10 forecasts bring 51 mm or more.
How windy will it get in Porto?
Gusts over 64 km/h: 3 in 10 forecasts at Tue 7 p.m. WEST. The middle forecast’s strongest gust is 60 km/h, Tue 1 p.m. Checked every six hours, so a brief peak can fall between.
How warm or cold will it be in Porto?
At the six-hourly times, the middle forecast runs from 14°C (Thu 7 a.m.) to 24°C (Sun 1 p.m.) WEST. The day’s real high and low can fall between those times.
Are any storms heading for Porto?
No storm Stormlines tracks has 1 in 10 forecasts passing its centre within 160 kilometres of Porto this week.

Chance of rain, six hours at a time

Tue 1–7 a.m.: 1 in 10 forecasts with measurable rain; middle forecast almost noneTue 7 a.m.–1 p.m.: 2 in 10 forecasts with measurable rain; middle forecast almost noneTue 1–7 p.m.: nearly all forecasts with measurable rain; middle forecast 4.3 mmTue 7 p.m.–1 a.m.: nearly all forecasts with measurable rain; middle forecast 18 mmWed 1–7 a.m.: 8 in 10 forecasts with measurable rain; middle forecast 0.7 mmWed 7 a.m.–1 p.m.: 6 in 10 forecasts with measurable rain; middle forecast 0.4 mmWed 1–7 p.m.: fewer than 1 in 10 forecasts with measurable rain; middle forecast almost noneWed 7 p.m.–1 a.m.: fewer than 1 in 10 forecasts with measurable rain; middle forecast almost noneThu 1–7 a.m.: fewer than 1 in 10 forecasts with measurable rain; middle forecast almost noneThu 7 a.m.–1 p.m.: fewer than 1 in 10 forecasts with measurable rain; middle forecast almost noneThu 1–7 p.m.: fewer than 1 in 10 forecasts with measurable rain; middle forecast almost noneThu 7 p.m.–1 a.m.: fewer than 1 in 10 forecasts with measurable rain; middle forecast almost noneFri 1–7 a.m.: fewer than 1 in 10 forecasts with measurable rain; middle forecast almost noneFri 7 a.m.–1 p.m.: fewer than 1 in 10 forecasts with measurable rain; middle forecast almost noneFri 1–7 p.m.: fewer than 1 in 10 forecasts with measurable rain; middle forecast almost noneFri 7 p.m.–1 a.m.: fewer than 1 in 10 forecasts with measurable rain; middle forecast almost noneSat 1–7 a.m.: 1 in 10 forecasts with measurable rain; middle forecast almost noneSat 7 a.m.–1 p.m.: 1 in 10 forecasts with measurable rain; middle forecast almost noneSat 1–7 p.m.: 3 in 10 forecasts with measurable rain; middle forecast almost noneSat 7 p.m.–1 a.m.: 4 in 10 forecasts with measurable rain; middle forecast almost noneSun 1–7 a.m.: 5 in 10 forecasts with measurable rain; middle forecast 0.3 mmSun 7 a.m.–1 p.m.: 6 in 10 forecasts with measurable rain; middle forecast 0.3 mmSun 1–7 p.m.: 7 in 10 forecasts with measurable rain; middle forecast 1.0 mmSun 7 p.m.–1 a.m.: 7 in 10 forecasts with measurable rain; middle forecast 0.5 mmMon 1–7 a.m.: 5 in 10 forecasts with measurable rain; middle forecast 0.3 mmMon 7 a.m.–1 p.m.: 6 in 10 forecasts with measurable rain; middle forecast 0.3 mmMon 1–7 p.m.: 7 in 10 forecasts with measurable rain; middle forecast 1.3 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, WEST.

The week, day by day

DayChance of rain2.5 mm or moreTotal by day’s endStrongest gustTemperature
Tue 29nearly allnearly all24 mm · 8 in 1060 km/h · 3 in 10 >64 km/h19°C–23°C
Wed 308 in 101 in 1027 mm · 8 in 1015 km/h17°C–20°C
Thu 1<1 in 10<1 in 1027 mm · 8 in 1025 km/h14°C–21°C
Fri 2<1 in 10<1 in 1027 mm · 8 in 1013 km/h16°C–23°C
Sat 34 in 101 in 1027 mm · 9 in 1013 km/h18°C–24°C
Sun 47 in 102 in 1028 mm · nearly all11 km/h19°C–24°C
Mon 5 (part)7 in 103 in 1033 mm · nearly all14 km/h18°C–23°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 1 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 Porto

No storm Stormlines tracks has 1 in 10 forecasts passing its centre near Porto 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 Porto’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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