Why hailstorms in Texas are getting more destructive

It will probably come as no surprise that hailstorms in Texas are causing more damage than they used to. The size of hailstones also seems to be growing with comparisons to baseballs, softballs, and even cantaloupes, being reported more often year after year. Both are trends that have caused people to wonder whether global warming is to blame.

The answer: maybe. But there are also other reasons hailstorms are becoming fiercer.

To understand how climate change could influence hailstorms, it helps to know one key factor in the creation of hail. It’s called updraft.

Updraft is the word for warm air rising from the Earth’s surface. In storms, it lifts moisture into parts of the atmosphere where that moisture condenses into rain.

You can think of a hailstone as a raindrop that has been pushed high enough into the atmosphere to freeze. When there is a particularly strong updraft, that speck of ice will be kept aloft longer, growing in size the longer it floats above us in freezing, cold air.

Eventually, those ice balls fall back to Earth, either because the updraft has weakened or because they have become so heavy that even a strong updraft can no longer support them.

Sometimes they melt on their way back down. Sometimes they land as hail.

The connection between a warming Earth and hail creation isn’t clear just yet

These mechanics behind hail creation are among the things scientists study when they look at whether a warming atmosphere could lead to larger hailstones.

A warmer earth creates stronger updrafts because heat rises. Warmer air also holds more water, which leads to greater precipitation.

Those two things could lead to more moisture being pushed higher into the atmosphere for longer, bringing bigger hailstones back to Earth.

But, warmer air is also more likely to melt that hail on its way back to Earth, causing researchers to question the overall impact. Does a warmer atmosphere increase the size of hailstones? Does it decrease the frequency of hailstorms? Is it a wash?

“I think, right now, it’s a little bit unsure as to whether global warming is going to result in larger hailstones,” Victor Murphy, a climate services program manager with the National Weather Service told KUT. “It’s sort of a push and pull as to what the overall impact is.

That answer might surprise you if you’ve been paying attention to the headlines. After all, hailstorms seem to be happening more frequently. They are also causing increasingly more damage across the country. And bigger and bigger hailstones are reported almost every year.

But that could have as much to do with human activity and recordkeeping, as it does with atmospheric conditions.

There are more ways and (and more people) to track hailstorms today

One reason hailstorms are difficult to study is that, like thunderstorms, they often strike relatively small geographic areas.

Temperature or rainfall data can be collected anywhere and compared over decades and centuries. But records on these types of localized storms are trickier because, for most of human history, they have struck where no one has been there to record them.

“If a tree falls in the forest, who hears it?” Murphy says. “Well if a large hailstone falls in a pasture who sees it?”

For this reason, “there is no reliable, long-term record of severe thunderstorms: tornadoes, hail, and strong winds,” according to a recent report on climate change in Texas from the State Climatologist’s Office.

But, as more and more people move to places, like Texas, that are prone to hailstorms, we are hearing more about those storms.

“With population growth, those pastures and farmlands are now subdivisions,” says Murphy. “So people are seeing those hailstones, reporting them.”

All that development in hail country also accounts, at least in part, for why the storms have become more destructive: hail is now falling on more human-built infrastructure.

Murphy adds that the advent of camera phones, social media and “storm chasing” as a hobby or profession also means larger hailstones are more likely to be spotted and reported.

Though this is not to say that global warming isn’t also playing a role.

That state climatologist’s report says that “indirect evidence supports an increase in the number of days capable of producing severe thunderstorms and an increase in the frequency of very large hail in early springtime.”

“But,” it adds, “these possible trends are too uncertain to quantify.”

Large research projects are currently underway to bring more certainty to the science.