The JS hook sends map bounds on load and on pan/zoom. The server
queries only scores within those bounds, dramatically reducing the
payload for band switches and map updates. At zoom 7 (DFW area)
this sends ~2k scores instead of ~95k.
Replace circle markers with a canvas tile layer that renders smooth,
flowing colored regions using bilinear interpolation between grid
points. Colors interpolate between tiers for gradients. ~95k grid
points at 0.125 degree resolution with wgrib2 extraction.
