IBM on Tuesday unveiled a global weather modeling system that will combine data from smartphones and aircraft to produce what it says will be hyper-accurate local forecasts.

The system, called the IBM Global High-Resolution Atmospheric Forecasting System, or GRAF, will create a one-day forecast updating every hour at a resolution of 3 kilometers, or about 1.9 miles — a notable upgrade for many parts of the world. The company is pitching GRAF as particularly useful in industries th…