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Precipitation types (rain, hail and snow)

• Precipitation occurs when the air is no longer able to hold the water vapor in it. The vapor condenses and then falls as rain, snow or hail.

Rain and its types:

Rain falls after the air is loaded with a large and sufficient amount of water vapor that it cannot carry, after the condensation process occurs, which is helped by the presence of condensation nuclei, such as dust and obstacles in the air, and the air temperature drops below the dew point.

Precipitation is classified according to its composition into:

1. Topographical rain: It occurs when the moist sea wind blows, hitting the opposite mountain slopes, rising to the top and with the decrease in the air temperature, condensation occurs, clouds form and rain falls.
2. Rain of the depressions: These rains spread in the middle shows that are exposed to the depression accompanied by the air fronts, where the air associated with the depressions rises to the top, causing the formation of cumulus clouds, which cause heavy rain.
3. Escalating (convective) rains: These rains spread in the tropics and tropics as a result of the intense heating, so the rising air currents activate, the evaporation intensifies, and the steamy air rises to the cold upper layers of the atmosphere and condenses, then heavy rain falls accompanied by lightning and thunder, especially in the afternoon hours.

the cold:

They are small solid globules of ice, formed by the transformation of water droplets in clouds and clouds into small ice globules, due to the temperature dropping below freezing, when these globules begin to fall carried by air currents rising to the top of the clouds, accumulating on them a new layer of ice, By repeating this process, its weight increases, and it falls in the form of cold.

ice:

It consists of thin ice crystals formed due to the decrease in the temperature of water droplets in the clouds and clouds below the freezing point, falling in the form of flying snow in the air due to its lightness. It builds up permanently because the temperature continues to drop below zero.

Thunderstorms:

Thunderstorms occur as a result of the formation of a dense chain of clouds in which an electrical discharge occurs between the negative and positive charges inherent in the clouds, resulting in lightning, thunder and thunderbolts.

Stages of thunderstorm formation:

1. The first stage (the formation of clouds): This stage is characterized by the activity of rising air currents that carry large amounts of water vapor due to the intense heating of the Earth’s surface, especially in the first half of the day.

2. The second stage (maturation): in which rising air currents are active and the process of condensation is active, either in the form of water droplets or ice crystals that grow until their weight increases, so that the rising currents cannot carry them, while the descending currents carry them, causing heavy rainfall,

The storm at this stage is accompanied by the following phenomena:

1. Lightning: An electric spark that occurs due to an electrical discharge caused by contact between negative and positive electrical charges inside a cloud or two clouds of different charge.
2. Thunderbolt: A flash that extends from the ground to the top due to an electrical discharge process between the bottom of the cloud with negative charges and the positive charges on the surface of the Earth.
3. Thunder: The sound caused by the expansion of air as a result of heating by lightning, and then suddenly contracting as a result of cooling after the passage of the electric spark.

3. The third stage: It begins when the downward currents spread, and the rising currents stop, then the clouds vanish and the amount of precipitation decreases. The occurrence of thunderstorms results in several risks, the most important of which are electrical appliances, ignition of fires in forests and homes, the heavy rains associated with thunderstorms cause floods.