Stationary Fronts
A stationary front is one that is not moving (i.e. the two air masses on either side are not moving perpendicular to the front – one is not displacing the other). This is depicted by an alternating red and blue line with triangles on the blue portion pointing away from the cool air mass and half-moons on the opposite side of the red portion of the line, pointing away from the warm front. A cold or warm front that stops moving becomes a stationary front. The difference in temperature and wind direction between either side of a stationary front is generally not large, but sometimes can be stark.