The HRRR over California

The High-Resolution Rapid Refresh is NOAA's operational 3 km model, re-run every hour over the continental United States. At this resolution California's weather stops being a smear: the marine layer hugging the coast, a Sierra crest wind event, thunderstorms firing over the Sacramento Valley and downslope gusts in the passes all resolve as themselves. The camera opens on the state; the sector chips and the two jump menus drill to an NWS office's area, and Shift with the arrow keys walks to the neighbouring one.

The timeline carries the whole cycle with a UTC tick strip reading the frames' own valid times. Fields are drawn straight from the raw NCEP GRIB2 output with no smoothing and no rescaling — colour ramps are pinned to absolute values, so a loop shows real intensity changes rather than a palette re-fitting itself each frame. Click any city for its full time series through the run.

Use the HRRR for the next 18 to 48 hours; for the longer view the GFS reaches ten days, and the National Blend is the calibrated forecast. Watches, warnings and advisories come from the National Weather Service — see the California alerts desk.