The first flakes of winter storm Jonas are just beginning to fall at the Mapbox Garage. Damon used forecast data from NOAA’s High Resolution Rapid Refresh Model to animate the storm’s arrival in the Mid-Atlantic. The map shows water equivalent accumulated snow depth, or WEASD, which we can think of as the volume of water contained in the snow on the ground.

We can see the storm approaching the Mid-Atlantic starting yesterday at midnight, and slowly moving through the area until Saturday at 2pm, when the animation (and HRRR forecast) ends.

HRRR-predicted water equivalent accumulated snow depth for the Mid-Atlantic, from Thursday 12am to Saturday 2pm