If the animation takes too long to load, stop the download and go to this page and try this site . A warm front occurs when a less dense air mass rides up over a more dense air mass. The following table shows the changes that occur in the weather elements at a station as a warm front approaches and passes a station. This image shows the less dense air behind a warm front being lifted by the more dense air ahead of the front. Generally from south to southeast Direction varies.
Fog often occurs near and ahead of front.
Usually overcast conditions with predominantly stratus and nimbostratus type clouds Decrease in coverage amount. May have scattered stratocumulus type and occasionally cumulonimbus type in summer months Precipitation Light to moderate rain, snow, sleet or drizzle Possibly light drizzle or no precipitation Usually none or light showers Visibility Poor to near zero in fog and precipitation Poor but slowly improving as front passes Fair, may lower in hazy areas. Dew Point Steadily rises as precipitation evaporates into cool air ahead of front Remains steady Rises in warm, moist air behind front and then remains steady An animation of a warm front with developing clouds and precipitation is provided by UIUC-CoVis Geosciences Web Server . If the animation takes too long to load, stop the download and go to this page and try this site . Stationary Fronts A stationary front occurs when the air masses on either side of the front are not moving toward each other.