Starting with one basic set of initial conditions, they run multiple forecasts—as many as 50 at the European Centre for Medium-Range Weather Forecasts, the world leader in ensemble forecasting.

These five weather apps give you detailed, real-time forecasts that go beyond the basic insights your phone's default app can provide.

During President Trump’s first term, one of his earliest official actions was to sign the Weather Research and Forecasting Innovation Act of 2017. This law significantly improved weather forecas ...