Extended Data Fig. 3. Case study of a precipitation event starting at 23:10 UTC on 4 May 2021, with a massive squall line that swept across several states in southeast USA.

Compared with other baselines, NowcastNet is the only model that simultaneously keeps the shape and intensity of the squall line. a, Geographic context for the predictions. b, A single prediction at T + 1 h, T + 2 h and T + 3 h lead times for different models. c, CSI neighbourhood at thresholds 16 mm h⁻¹ and 32 mm h⁻¹. d, PSD at different wavelengths. Images are zoomed in 768 km × 768 km to highlight local details. Precipitation data obtained from the MRMS²⁶ dataset and maps produced with cartopy and Natural Earth.