A subjective term for temperatures between cold and hot. In meteorology , an air parcel that is warm is only so in relation to another parcel. The horizontal movement of warmer air into a location. The leading edge of an advancing warm air mass that is replacing a retreating relatively colder air mass. Precipitation , in the form of rain , snow , or drizzle , is generally found ahead of the surface front , as well as convective showers and thunderstorms .
Fog is common in the cold air ahead of the front.
Although clearing usually occurs after passage, some conditions may produced fog in the warm air. Contrast with a cold high . A low pressure system that has its warmest temperatures at or near the center of circulation . Also referred to as a warm core low. A forecast issued when severe weather has developed, is already occurring and reported, or is detected on radar .