WOOFWhat am I looking at?
These maps are Forecast Raven's own model runs. WOOF is Recast Systems' GPU port of WRF-ARW, the community regional weather model. Each run goes on a single rented GPU and is drawn hour by hour.
A run starts from a Day 4 forecast of ECMWF's IFS (the 0.1° open data) and takes its boundaries from the same IFS run, so the forecast hour on the timeline counts from the IFS cycle: F72 onward. Starting from a forecast rather than an analysis, the first few hours are the model spinning up its own clouds, rain and fine detail; radar and precipitation begin an hour in.
The domains, picked in the bar at the top: East 9 km (the Plains to the Atlantic, Days 4–7) runs NOAA's RAP physics, with the Grell-Freitas cumulus scheme for storms smaller than the grid; East 9 km nudged is the same model and domain with spectral nudging: above about 1.5 km, the largest weather patterns (wavelengths longer than about 1,500 km) are gently pulled toward the ECMWF forecast on a three-hour time scale, so the run keeps ECMWF's troughs and ridges and adds its own detail beneath them, while the un-nudged run is free to drift from them; Northeast 3.5 km and Great Lakes 3 km (Days 4–6) run the HRRR's, with storms resolved by the grid itself; Southeast 3.5 km (Days 4–6) runs the same HRRR family with TEMPO microphysics, the Thompson successor NOAA's next regional model (RRFS v2) is moving to.
From the 9 km run's full column we also compute integrated vapour transport (the moisture an atmospheric river carries), potential vorticity on the 320 K surface and the potential temperature of the dynamical tropopause (where PV reaches 2 PVU): the upper-level troughs and ridges that steer the weather below. Snowfall is estimated from hourly gains in modelled snow depth, because the model writes no snowfall field; it runs low where snow lands on warm ground.
These are test runs of the pipeline, not an operational service, and they are not yet updated on a schedule. For watches, warnings and advisories, your national weather service is always the authority.
Contains modified ECMWF open data, CC BY 4.0; ECMWF does not accept any liability for this use. WOOF by Recast Systems; WRF by NCAR and partners; HRRR and RAP physics by NOAA GSL. The map viewer is Forecast Eagle's explorer.