Lines on a weather map connecting places of equal air pressure are called

Lines on a weather map connecting places of equal air pressure are called isobars

Explanation:

Isobars are lines that represent areas of constant or equal pressure. In weather maps you can find "L" or "H" letters that stand for low or high pressure, the lines used to circle these letters are the isobars.

These isobars can give information about precipitations (lowest pressures) or sunny conditions (high pressures) even windy conditions where lines are close together.

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