The synoptic weather map is the working drawing of early-20th-century forecasting: thin black isobars closing into pressure curves, blue cold fronts and red warm fronts marching across coastlines, and H/L marks pinning the pressure systems. Born in the Bergen School of Vilhelm and Jacob Bjerknes, it turned the sky into a readable diagram.

This design system rebuilds that printed-chart character — cool chart-white stock, cold-front blue as the signature accent, letterpress grain, and a strict line-drawn grammar of triangles, semicircles, and isobars.