2-27. An advancing warm air mass me

2-27. An advancing warm air mass meets a colder mass and rides up over it (Figure 2-11). Warm fronts are generally oriented north to south, northwest to southeast, or east to west, and change their direction more often than cold fronts do. Warm fronts advance between 150 to 200 miles per day. Because of their slower speed, they are often overtaken by a following cold front. Approaching warm fronts signal milder weather than do cold fronts. Water fronts arepreceded by low stratus cloud formations and moderate but extended rains. Another indicator of a warm front is a slowly falling barometer. As a warm front passes, cumulus clouds replace stratus clouds, and the temperature and barometer both rise.