Most rain associated with warm fronts is a light to moderate rain that can include fog. Warm fronts tend to precede a cold front and often sit to the northeast of a low pressure system. Behind a warm front, skies tend to be relatively clear but gradually will change. This is because a warm front is commonly followed by a cold front.
These occur when a front line gets stuck between two opposing front lines e. Weather along these fronts tends to more closely resemble warm fronts, making them most dangerous in the winter months when they can cause several days of continuous snowfall in one area. Occluded fronts occur when faster-moving cold fronts overtake slower-moving warm fronts.
Usually an occluded front is a sign that the frontal line is about to break apart and dissipate. Weather behind the front line will be similar to that of a cold front and is where most of the severe weather could be present.
Ahead of the front line weather would be similar to that of a warm front and tends to be milder. Anthony Petronzi began writing in One air mass is lifted above the other, creating a low pressure zone. If the lifted air is moist, there will be condensation and precipitation.
Winds are common at a front. The greater the temperature difference between the two air masses, the stronger the winds will be. Fronts are the main cause of stormy weather. At a stationary front the air masses do not move. A front may become stationary if an air mass is stopped by a barrier, such as a mountain range. A stationary front may bring days of rain, drizzle, and fog. Winds usually blow parallel to the front, but in opposite directions.
After several days, the front will likely break apart. When a cold air mass takes the place of a warm air mass, there is a cold front.
Imagine that you are standing in one spot as a cold front approaches. Along the cold front, the denser, cold air pushes up the warm air, causing the air pressure to decrease. If the humidity is high enough, some types of cumulus clouds will grow. High in the atmosphere, winds blow ice crystals from the tops of these clouds to create cirrostratus and cirrus clouds.
At the front, there will be a line of rain showers, snow showers, or thunderstorms with blustery winds. A squall line is a line of severe thunderstorms that forms along a cold front.
Behind the front is the cold air mass. This mass is drier so precipitation stops. The weather may be cold and clear or only partly cloudy. Winds may continue to blow into the low pressure zone at the front. The weather at a cold front varies with the season. Think of warm air as a person holding a million birthday balloons. When a cold front comes through, it forces the person to let go of all the balloons.
A cold front does the same thing with a warm air mass. The warm air is forced to rise because it is less dense than the cold air. This causes a surge of rising motion with is known to generate thunderstorms. Sometimes, these storms can be nasty! Fill the plastic tub with warm water and add red food coloring to one end of the tub. This is your warm air ahead of the cold front. Place the blue ice cubes on the other end of the tub.
Results: You will see the cold water from the cubes sink straight to the bottom of the tub and spread outward, under the warm water. Soon you will see red food coloring on top of the blue food coloring.
Conclusion: The cold water is more dense than warm water and it sinks to the bottom of the tub. When the cold water spreads across the bottom of the tub, the warm water is forced to rise. The rising motion simulates the development of thunderstorms along the cold front.
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