Whats the difference between the dewpoint temperature and relative humidity?
The dewpoint temperature is an absolute measure of moisture in the atmosphere (if it’s 65F, then everything colder than 65F will have water condense on it). Relative humidity is a relative measure of moisture in the atmosphere compared to what it can hold. If the relative humidity is 50%, that means the air is “half saturated.” It’s holding about half the water vapor it can hold at that temperature. What causes “Santa Ana” winds? Winds that come from the northeast or east travel over several small mountain ranges before arriving in San Diego. As wind goes up over a mountain, it cools and condenses–leaves some clouds on the windward side, and that’s moisture coming out of the atmosphere. As that air travels back over the mountain and down into the next valley, it warms up due to compression–and it’s drier(since it lost that moisture)–so it’s a hotter, drier air flow. Each time the air goes up and over, this happens–so by the time it reaches us it’s extremely warm and usually very dr
