Pressure usually falls for an appreciable length of time before the fron-tal passage. Normally, it is steady after passage. The wind in advance of a warm front in the Northern Hemisphere is usually from the southeast, shifting to southwest after passage. The wind speed normally increases as the front approaches. The wind shift accompanying a warm front is seldom as abrupt as with a cold front.
Warm fronts are nearly always well defined by typical stratified clouds.
The cloud types that form after passage of the warm front are typical of the warm air mass. The precipitation area of warm fronts extends about 300 miles in advance of the surface front. Precipitation occurs mainly in the form of continuous or intermittent rain, snow, or drizzle. However, when the warm air is connectively unstable, showers and thunderstorms may occur in addition to the steady precipitation. Temperature and dew-point changes.