What makes tornado alley so unique?

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The right conditions for tornadoes can occur any time of the year in any location. With no start and end date for 'tornado season' it's interesting to explore why there will be a peak in occurrences over the up coming months.

As the continents warm up due to the tilting Earth, the air close to the ground is warmed up too. Spring is a transitional period for the climate, and there are more chances of cooler air meeting with warmer air. This leads to instability in the atmosphere and upwelling convection. Where this convection is strong, storms can develop and where the convection is really really strong this can spawn a tornado.

The unique positioning of the Great plains in US - areas of which are dubbed tornado alley - means that it will see a peak in tornado occurrences through spring and summer as a result of it's bordering air masses. It's a question of geography. Although tornadoes have been reported in mountainous areas, the relatively flat land in the Great Plains creates the perfect conditions for a severe storm. The cold dry polar air from the Rocky mountains of Canada meets with warmer moist winds from the Gulf of Mexico. A large number of tornadoes form when these two air masses meet, along a phenomenon known as a "dryline."

Next week we will take a look behind chasing a storm with Netweather's Paul Sherman. If you are going on a spot of storm chasing get in contact with us.

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