That depends entirely upon where you are in the world but dew is unconnected to time of year as such. It forms when it cools enough at night for the RH to get to 100%. In some parts of the world that could be every night, in others never or very rarely.
NIGHT
Dew
when the day gets warmer dew melts
Dew forms when the air just above the ground is cooled to its dew point (a temperature at which the water dissolved in the air comes out of the air). The air above the ground is cooled because the ground radiates heat into space. If there are clouds overhead the clouds reflect the heat back to the ground so it does not cool and o dew forms. If it is windy then the air just above the ground keeps on getting mixed with the air higher up and the air does not cooled to the dew point and no dew forms. Thus to form dew you need a still clear night.
If there is no dew on the grass in the morning, it means that it did not get cold enough to condense the water vapor in the air. The dew point, the temperature at which dew forms, depends on the humidity: if it is very humid, dew will form at a relatively warm temperature, but if it is very dry, dew will not form until it gets quite chilly.
fogfog
no.
DEW
Many people know that mountain dew is good. If you drink it at night you should be happy the next day with a good sleep.
none of your beeswax
Dew
It has to do with the temperature and dew point on that particular day.
dew, due, do
Dew-Dew-Dewey Day was created in 1927.
When dew forms in the winter, it forms at night and its colder at night so the dew freezes at that point in freezing.
High air humidity, low temperature and absence of sunshine during night with minimum air velocity are needed to form dew. These things are very common during autumn and spring seasons causing maximum dew formation.
The air near the ground cools to the DEW POINT.
The Dew Point is the temperature at which the air is at 100% Relative Humidity. If the temperature fall below the Dew Point, then there is more moisture in the air than it can hold, and water condenses in the form of dew, mist, rain, etc.