Spring Brings Devastating Squall Lines

Spring often signifies sunshine and warmer temperatures, but it can also spark damaging thunderstorms. One such type of severe weather phenomenon is known as a squall line.

While tornadoes are known for their power and the damage they cause, squall lines can also be dangerous and deadly. Squall lines occur when intense thunderstorms organize into a solid line. Along the leading edge of the storms, winds can be quite destructive, sometimes topping 60, 70 and even 80 mph.

When the line begins to bend out forming a backwards C, damaging winds can become even stronger, often leading to power outages. This bowing out of the squall line is often termed a bow echo, due to its resemblance to a bow and arrow.

So why are there more squall lines in the spring and early summer months? Well as April turns into May, several key ingredients needed for the formation of this type of severe weather come together.

Much like what is seen over Tornado Alley, warm, moist air rides north from the Gulf of Mexico, while cooler, drier air rushes down from the north.

Strong jet stream dynamics and higher winds in the atmosphere are the final pieces of the puzzle.

While most tornadoes tear across the infamous Tornado Alley into June, squall lines have less of a definitive area they are restricted to. Squall lines have been observed nearly every month of the year and have been witnessed over the majority of the states in the U.S.

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