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Cardiff weekend weather

This weekend in Cardiff, Wales, model by model. Weekend forecasts are far enough out that the models often split - so we show you where.

Weekend

The models centre on about 19° across the weekend. Agreement is medium - plausible, but worth re-checking closer to the day. Rain chance reaches 100% on at least one model.

Today

2026-09-19 — every model, side by side
Met OfficeUKMO model
18°
Light rain
High 18°·Low 16°·Rain
EuropeanECMWF
19°
Drizzle
High 19°·Low 16°·Rain 100%
AmericanNOAA GFS
20°
Light drizzle
High 20°·Low 15°·Rain 71%

All 3 models land within 2° of each other for this day — that is a forecast you can plan on.

Tomorrow

2026-09-20 — every model, side by side
Met OfficeUKMO model
19°
Cloudy
High 19°·Low 13°·Rain
EuropeanECMWF
18°
Cloudy
High 18°·Low 11°·Rain 24%
AmericanNOAA GFS
19°
Light drizzle
High 19°·Low 12°·Rain 24%

All 3 models land within 1° of each other for this day — that is a forecast you can plan on.

Where the models disagree

temperature and rain, judged separately
DayTemperatureRain
Today±2°18° to 20°±29%71% to 100% chance
Tomorrow±1°18° to 19°models agree24% to 24% chance
Mon±3°19° to 22°±14%0% to 14% chance
Tue±2°20° to 23°±12%0% to 12% chance
Wed±5°19° to 23°±21%3% to 24% chance

The models often agree on temperature and still split on rain, and rain is usually what decides whether a plan survives. A wide rain range means the shower is genuinely uncertain, not that the forecast is wrong.

Common questions

Will it rain this weekend?
At least one model puts the weekend rain chance as high as 100%. Weekend forecasts sit far enough ahead that models frequently disagree on showers - when they do, no single app can honestly tell you it will or will not rain.
How reliable is a weekend forecast?
It depends how far away the weekend is. Forecast error grows steadily with lead time, so a Saturday forecast made on Friday is far stronger than one made the previous Monday. The honest signal is model agreement: when they converge the forecast is solid, and when they spread the weekend is genuinely uncertain.

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