Meterology revolves as much around good weather models as it does good weather data, and the core US model is about to receive a long-overdue refresh. NOAA has upgraded its Global Forecast System with a long-in-testing dynamical core, the Finite-Volume Cubed-Sphere (aka FV3). It's the first time the model has been replaced in roughly 40 years, and it promises higher-resolution forecasts, lower computational overhead and more realistic water vapor physics.
The results promise to be tangible. NOAA believes there will be a "significant impact" to one- and two-day forceasts, and improve the overall accuracy for forecasts up to a week ahead. It also hopes for further improvements to both the physics as well as the system that ingests data and invokes the weather model. This is on top of previous upgrades to NOAA supercomputers that should provide more capacity.
The old model will still hang around through September, although not as a backup -- it's strictly there for data access and performance comparisons. FV3 had been chosen years ago to replace the old core, and it's been in parallel testing for over a year.
Not everyone is completely satisfied with the new model. Ars Technica pointed out that the weather community is concerned about surface temperatures that have skewed low, for instance. It should be more accurate overall, though, and that could be crucial for tracking hurricanes, blizzards and other serious weather patterns that can evolve by the hour.