Chorus Weather: know when to trust the forecast

In one line

Chorus Weather shows whether the world's big forecast models agree, so you know when to trust the forecast and when to have a plan B.

Short description

Chorus Weather is a companion to the weather app you already use. It compares the major forecast models (ECMWF, the US GFS, Germany's ICON and the UK Met Office) and gives one clear verdict: Agree, Mixed or Split. It does this in the app and in Home Screen and Lock Screen widgets.

Long description

Most weather apps show a single forecast, quietly blended from several computer models. When those models agree, that forecast is reliable. When they don't, it can be a coin toss, and you'd never know.

Chorus Weather shows you. It compares the world's leading forecast models: the European Centre's ECMWF, the US GFS, Germany's ICON and the UK Met Office, including its 2 km model for the UK. It then sums up their agreement in one word: Agree, Mixed or Split. Plain-English headlines explain what the models disagree about ("Some models show rain, others don't"), and a 24-hour chart shows every model's line, so you can see exactly when the forecast becomes uncertain.

Home Screen and Lock Screen widgets bring that verdict to a glance, so you know before you open any app whether today's forecast is one to rely on.

Chorus is free. Chorus Plus adds the widgets, two more models (Japan's JMA and Canada's GEM) and up to 20 saved places, with a one-week free trial. Chorus needs no account, and locations are rounded and never stored.

Chorus is made by James Shaw, an independent developer in the UK.

Fact sheet

Developer: James Shaw (James Andrew Shaw Ltd), UK
Release date: Released 4 November 2026
Platforms: iPhone, also runs on Apple silicon Macs. Requires iOS 18.0 or later
Price: Free. Chorus Plus £1.99 a month or £14.99 a year, with a one-week free trial
App Store: https://apps.apple.com/app/id6822343590
Website: https://chorusweather.app
Press contact: support@chorusweather.app