what exactly is 'dewpoint' in a weather forcast?

Answer 1

It's the temperature at which evaporated water in the air turns back into a liquid.

Answer 2

Dew point is defined as the temperature at which air would become saturated if it were cooled sufficiently, a further lowering of this temperature being responsible for spontaneous condensation.
This can also be explained in terms of vapour pressure.Dew point of air is the temperature for which the saturated vapour pressure is identical with the actual pressure of the vapour in the air as the water vapour whose presence in the atmosphere determines the dew point temperature, also contributes to the total pressure of the air.

Answer 3

The 'Dew-point' is the temperature at which water vapour in the atmosphere will condense into water droplets...forming the morning dew you see in summer when the temperature is cooler than the daytime.
As the daytime temperature increases, the atmosphere can hold more moisture. When it cools at night, the air becomes saturated and can't hold as much water. Some of it will condense out.

Answer 4

That's the point when the relative humidity and the temperature reach the point where dew (condensation of the water vapor in the air) forms at ground level.

Answer 5

It is the temperature at which the existing water vapor will condense into fog, or settle as droplets on a surface.

Answer 6

as everyone's said its the point at which humidity turns to moisture 'dew' if there is a nice hot high pressure system above you full of moist air, that is then confronted by a mass of low pressure cool air 'wallah' rain!

Answer 7

dewpoint is the tempature at which the air must be at to be fully saturated.