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those squiggly lines on the news are readable.

given a pressure map, call tomorrow’s weather — then watch it arrive

A weather map’s contour lines connect points of equal pressure, and their spacing is the whole forecast in one glance: rings packed tight mean a steep pressure drop and strong wind, rings spread wide mean almost no gradient and calm. In the Northern Hemisphere air spirals counter-clockwise into a low and clockwise out of a high, which is why a cyclone visible from space always spins the same way here. None of this requires reading a number off the map — the shape alone tells you what tomorrow does.

Concepts: fluid-flow, pattern.

An interactive you play with one thumb, on Wundr.