The moisture comes from the water vapor in the air. As the temperature drops to near the dew point, the water vapor condenses on cold surfaces in the desert.
Dew is formed by condensation.
Dew formation in deserts is less common compared to other regions due to the arid climate and low humidity levels. Dew forms when the temperature of the surface cools down to the dew point temperature, causing water vapor in the air to condense into liquid water droplets. In deserts, the temperature often drops rapidly at night, but the low humidity levels limit the amount of water vapor available for condensation, resulting in less frequent dew formation.
light rain
Deserts generally have very low humidities. For dew to form, the relative humidity would have to be at, or very near to, 100%. That is a rarity in a desert.
DEW
These are called dew drops. They form when the temperature of the surface cools down causing water vapor in the air to condense and form small droplets of water. Dew is more likely to form on clear, calm nights when the temperature drops close to the dew point temperature.
Those drops of water are called dew. Dew forms when the temperature of the surface cools down and reaches the dew point, causing water vapor in the air to condense and form small droplets.
When the temperature comes down to the dew point, the air can support no more water vapour and the dew begins to to form. Air can absorb more water vapour as the temperature rises, so the difference between the dew point and the actual temperature gives a measure of the humidity.
Dew forms when the temperature drops to the dew point, causing water vapor in the air to condense into liquid water on surfaces. Dew may not form if the air temperature does not cool enough to reach the dew point, if there is insufficient moisture in the air, or if the surface is not conducive to dew formation (e.g., if it is warm or if there is strong wind).
Water vapor in the air comes into contact with the cold surface of the can, causing it to condense into liquid water. This is similar to how dew forms on grass in the early morning.
Dew is less likely to form in dry environments, such as deserts and arid regions, where the air is typically dry and temperatures can fluctuate greatly between day and night. In these areas, the conditions are not conducive for dew to form due to the lack of moisture in the air.
water droplets in the air form rain which is part of the water cycle