When a front passes over an area, it means a change in the weather. Many fronts cause weather events such as rain, thunderstorms, gusty winds, and tornadoes. At a cold front, there may be dramatic thunderstorms. At a warm front, there may be low stratus clouds.

There are four basic types of fronts, and the weather associated with them varies.

• Cold Front. A cold front is the leading edge of a colder air mass.
• Warm Front. Warm fronts tend to move slower than cold fronts and are the leading edge of warm air moving northward.
• Stationary Front.
• Occluded Front.

Basically, a weather front represents a boundary between two different air masses, such as warm and cold air. If cold air is advancing into warm air, a cold front is present. On the other hand, if a cold air mass is retreating and warm air is advancing, a warm front exists.

There are four types of fronts that will be described below: cold front, warm front, stationary front, and occluded front.

The similarities between a warm front and a cold front are: they are both fronts, they both form some type of clouds, they both produce some type of rain, they both make some kind of weather. Cold fronts are defined by cold air advancing, sliding under and displacing warmer air – they are steeper and move more quickly.

A front is a weather system that is the boundary separating two different types of air. One type of air is usually denser than the other, with different temperatures and different levels of humidity. This clashing of air types causes weather: rain, snow, cold days, hot days, and windy days.

Stationary fronts appear on weather maps as alternating red and blue lines, with blue triangles pointing towards the side of the front occupied by warmer air, and red semi-circles pointing towards the cold air side.

However, depending on the length of the cold front, portions of the front may move toward the east, while other portions move south. Some sections of the front may move faster than others. Active cold fronts (slow moving) average 15 knots. Inactive cold fronts (fast moving) have an average speed of 25 knots.

Cold fronts can cause dramatic temperature changes and can create severe weather. Cold air is more dense or weighs more than that of warm air. The molecules in cold air are packed more tightly together making it more dense.

Cold fronts occur when warm air is pushed up into the atmosphere by colder air at the ground. These fronts tend to move faster than the other types of fronts and are associated with the most violent types of weather such as severe and super cell thunderstorms, although any type of front can produce these same storms.

An Occluded Front forms when a warm air mass gets caught between two cold air masses. The temperature drops as the warm air mass is occluded, or “cut off,” from the ground and pushed upward. Such fronts can bring strong winds and heavy precipitation.

As the warm air is pushed higher, the moisture it carries condenses and falls as rain. This is why a lot of heavy rain is produced along a cold front but once the cold air mass has come in this often abruptly changes to a clear spell of weather.

The effects from a cold front can last from hours to days. The air behind the front is cooler than the air it is replacing and the warm air is forced to rise, so it cools.

What are the first signs of an approaching warm front? Wind, Drop in air pressure, Darker taller clouds, heavy rain, increase in humidity.

After the warm front passes conditions completely reverse. The atmospheric pressure rises slightly before falling. The temperatures are warmer then they level off. The winds in the northern hemisphere blow south-southwest in the northern hemisphere and north-northwest in the southern hemisphere.

Warm fronts produce clouds when warm air replaces cold air by sliding above it. Many different cloud types can be created in this way: altocumulus, altostratus, cirrocumulus, cirrostratus, cirrus, cumulonimbus (and associated mammatus clouds), nimbostratus, stratus, and stratocumulus.

Based on your observations, what do cold fronts seem to have in common? They are windier and have clouds. When cold air hits warm air it pushes the warm air up. The rising warm air cools quickly, resulting in condensation, clouds, and stormy weather.

The air mass behind a warm front is likely to be warmer and more moist than the one before the front. If a warm front is approaching, light rain or light winter precipitation is possible before and as the front passes. Behind the front, expect clearing skies, warmer temperatures and higher relative humdities.

Warm fronts are typically characterized by a transition from southeasterly to southwesterly winds. Unlike cold fronts, winds along the front itself are generally light and variable. Warm fronts, as their name implies, are also characterized by a rise in temperature, but also humidity.

A warm front is the boundary between a mass of warm air and a retreating mass of cold air. At constant atmospheric pressure, warm air is less dense than cold air, and so it tends to override, rather than displace, the cold air.

Stationary Front: a front that is not moving. When a warm or cold front stops moving, it becomes a stationary front.

When a warm air mass meets a cold air mass, the warm air rises since it is lighter. As it rises, the warm air cools rapidly. This configuration, called a cold front, gives rise to cumulonimbus clouds, often associated with heavy precipitation and storms.

At a front, the two air masses have different densities, based on temperature, and do not easily mix. 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.

Stationary Fronts

The denser, cold air pushes up the warm air mass approaches altocumulus. Larger rotating system called a mid-latitude which front is most likely to last for days that air mass at the front approaches tornadoes!

Front, in meteorology, interface or transition zone between two air masses of different density and temperature; the sporadic flareups of weather along this zone, with occasional thunderstorms and electrical activity, was, to the Norwegian meteorologists who gave it its name during World War I, analogous to the …

A warm front will steadily rise _________the cooler air and create gentle rain showers. An Occluded Front is formed when a ________front catches and overtakes a warm front.