Q: You often hear about a “ridge” and a “trough.” What are they?
A: Both terms refer to conditions in the air, says Brent McRoberts of Texas A&M University. “Air is usually associated as being part of a mass that is high pressure or low pressure,” he explains. “A trough is an area of low pressure, either at the surface or higher aloft. A ridge is just the opposite – it refers to a high pressure air mass. Both of these can tell us a lot about the weather in a particular area.”
Q: How is that?
A: The type of air can often determine if it’s going to be a nice day or stormy one, McRoberts says. “Usually, strong ridges are accompanied by warm and dry weather conditions at the surface,” he says. “On the other hand, strong troughs are often preceded by stormy and sometimes violent weather conditions. A strong upper air trough can often push a cold front through. So it’s a good idea to notice where ridges and troughs are because they can affect the weather where you live.”