What does the broken orange line mean on a surface weather map?
The broken orange line shows an elongated region of low atmospheric pressure, commonly referred to as a trough. Low surface pressure often indicates upward motion in the atmosphere, which can be associated with cloudy or stormy weather that s occurring near and to the east of the trough. West of the trough, pressures are higher, indicating a sinking motion in the atmosphere, which inhibits clouds and precipitation. Learn more about how troughs affect weather at this USA TODAY resource page.
