KNOXVILLE, Tennessee — It's been a wet start to the year here in East Tennessee.

For a while it seemed like the rain would never end. 

Just when you think the rain is finally gone, it comes back, and it comes back strong.

There are 11 days left in April and we've already seen 4.21 inches of rain this month. That's past the average April rain total of 4.01 inches, and more rain is on the way.

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Storms this time of year swing from sprinkles to severe, but what makes a storm severe? It's all in the strength.

A thunderstorm is considered to reach severe limits if it can produce winds of 58 mph or greater and hail at least 1 inch in diameter.

That's the size of a quarter. 

So why does severe weather happen in the spring? It has to do with a whole slew of different temperatures in different parts of the country.

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Summer weather is starting in the south but winter weather is still hanging around the north.

When those air masses clash, we get severe storms.

In East Tennessee, they create tornadoes, large hail, and most commonly damaging winds.

10News meteorologists said so far the 2019 spring severe weather season has been pretty mild, but it's not over yet.

It runs from March through the end of May or early June. While there're no severe storms in the immediate forecast, it's always good to be ready for anything.

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