What these are
Every table here can be applied to a field in the four explorers and the locked chart viewer, from the Colour table menu beside the field list. Nothing is re-rendered when you do. The frames are 8-bit palettised PNGs whose palette is the colour scale — a few dozen entries, about a hundred bytes inside a frame of several hundred kilobytes — so switching tables rewrites just that chunk. The forecast in the image, the indices the probe reads back, is untouched.
What the site draws by default are ECMWF's own tables, and they are here too as the ECMWF ecCharts pack: the Magics named colours on the published level breaks, discrete, because the banding is most of what makes a chart read as ECMWF's rather than as a generic rainbow, and a smooth version of one is a different table with the edges moved. The rest are there for comparison and for taste.
A table that declares the field's units is read at the field's own numbers — a °C table puts its freezing colour on 0 °C, wherever that falls in the scale. Much of the library was built for American maps and speaks °F and inches, and the 298 tables in the AWIPS pack name themselves by product rather than by quantity and carry no units at all; those are stretched across the field's range instead. Both are useful; only the first is a statement about values.
Tables are frozen into data/ramps/ with a content hash, so a ramp
cannot drift underneath a published image, and the schema is the one Forecast
Eagle and ecmwf-charts use, so a table moves between the three unchanged. To make
a new one, fork any of these in the
colour-table builder and see it on a real forecast before
you commit it.