This app shows a 72-hour probabilistic weather forecast by blending four
weather prediction models: NOAA GEFS (31-member global ensemble), NOAA HRRR
(high-resolution hourly), ECMWF IFS ENS (51-member global ensemble), and ECMWF AIFS
(AI-based deterministic global). The shaded bands on each chart show forecast uncertainty
— the median line is the most likely outcome, the darker band spans the
10th–90th percentile range, and the lighter band shows the full min–max
envelope.
Magic Blend weights each model by its recent accuracy at your location
(inverse-squared error), so better-performing models contribute more. Current weights are
shown below. All forecast data is sourced from
dynamical.org's open
Zarr stores.