CloudsClouds

Relationship of lapse rate and humidityRelationship of lapse rate and humidityFort Worth

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Temp and Relative Humidity

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Compare the lapse rate from the slope at 800 – 2700 & 2700 - ~4700. How does this affect relative humidity? Now, look at temperature and relative humidity at an altitude about 4800. What is happening?

Find the clouds hereFind the clouds here

Fort Worth Oct 23

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temperature and relative humidity

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What is going on here?What is going on here?

Topeka Kansas 10/24/02

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Temperature and Relative Humidity

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Orographic Lifting can form cloudsOrographic Lifting can form clouds

What is meant by lifted condensation level? - The height at which clouds form. That is the height the water vapor has to reach to cool to its dew point. Air that is forced upward will cool. When it reaches its condensation level, condensation of water vapor will form clouds. Drier air will rise more before the temperature drops enough for water vapor to condense and form clouds.

Rain Shadow Desert LinkLatent heat summary againActivity and worksheet

Frontal wedgingFrontal wedging

Other methods of lifting

ConvergenceConvergence

ConvectionConvection

Clouds can also form from horizontal movement of air. If the air moves over a cooler surface, the dew point will be reached and water vapor will condense to water. This happens commonly when warm moist ocean air moves over cool land, forming low layered (stratus) clouds or fog.

Generally cumulus clouds form by upward movement of air which causes it to cool. When it rises enough to cool to its dewpoint the water vapor condenses, and clouds form.

Cirrus Clouds – high clouds made of ice crystals

Altocumulus

Cirrocumulus

Measuring Rain – Rain GaugesMeasuring Rain – Rain Gauges

Formation of Sleet