(WBTV) - We all know what a dry summer it has been. Many days, no one got rain but it seemed if anyone got it, it would be the mountains.
There's a reason for that!
It's called orographic uplift. Really all that means is air rising over mountains.
If you have wind blowing on flat ground, where will it tend to go? Straight ahead, right? If you have wind blowing toward mountains, it can't go straight through them… or under them… or around them. The air has to go somewhere so it rises up and over them.
When this happens, the air is cooled as it rises. The relative humidity increases because cooler air can hold less water. That means it gets closer to saturation as it cools. Clouds can form and those clouds can then produce rain.
Wind direction also plays a part. If the wind blows toward our mountains from the west, the western slopes are the most likely to pick up rain. Sometimes, the eastern slopes miss out. It's something we call the rain shadow effect.
As the air rises over the mountains, it cools and condenses. The opposite happens once it gets over the mountain tops. The air sinks and warms. If the clouds dissipate so does the rain.
Hopefully we will ALL get rain this week… There are decent chances from Monday through Tuesday morning. The problem is that it looks to be fairly light rain. At this point, we'll take whatever we can get!