Ridges And Troughs

Did late Fall 2016 get traded in for the summer warmth? Many of us are enjoying this ‘tropical heat wave’ we are having, while some are a bit confused. Early November is a time when people drag out last year’s collection of winter clothes and pray that it doesn’t snow before Thanksgiving. Stringing Christmas lights in the heat seems socially acceptable but feels out-of-place. Although, this year may just be a little different. From the west coast to the central states, a ridge is right above us. So, what exactly is a ridge? Why is it conveying such warm and dry conditions? What would the opposite of it be called?

Fig. 1
Fig. 1
Fig. 2
Fig. 2

Let’s start off with the basics! Ridges are associated with high heights. High heights tend to turn the wind clockwise and outwards around them. They also diverge and sink. As shown in Fig. 1, you can see the line go up-and-around like a hill you climb up to go sledding down. Or in other views, it is an upside down ‘u’. High height go hand-in-hand with clear skies. Usually, we have more solar radiation from the sun which warms us up. This is currently where we stand. In Fig. 2, we can see that upside down ‘u’ right over Montana as it dips down by the North Dakota/ Minnesota border. Progressing along slowly, this motion is where we have stood for the past several days. Whether that be positive or negative, it helps us stay warm and cozy.

Trough’s on the other hand are the complete opposite. As seen in Fig. 1, they are ‘u’ shaped. They are associated with low heights. Low height move the wind counter clockwise and inwards. They converge and rise. Shooting those moist, warm temperatures up, most likely develop those clouds to carry some precipitation. In Fig. 2, a trough is headed right in front of the ridge from Pennsylvania to down south. They may get some precipitation, if everything goes right.

Hopefully, this ridge will stay over us longer. Many people may want the November experience with cold, brisk weather. As the saying goes, “what goes up, must come down”. Those sultry high temperatures will be expected to leave relatively soon and the trusty cold weather will prevail. By understanding ridges and troughs though, you can more readily comprehend what is happening around us. So, go ahead and peruse at some weather maps! It’s fun to gain knowledge as you go!

By Courtney Steimann

Sources:

Storm Prediction Center Upper Air Maps. 2016. National Weather Service Storm Prediction Center, United States of America. Storm Prediction Center, NOAA/National Weather Service. Web. 9 Nov. 2016.