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| This giant hailstone landed in Texas last Sunday. |
That was one of many hail storms in a nasty, busy hailish here in the United States. (Yes, I invented a new word, so sue me).
As the Washington Post reports, spring is a busy time for hail, as it is severe weather and tornado season. This year seems to be even worse than usual.
That makes sense. The weather pattern has featured extra doses of tornadoes and severe thunderstorms this spring. It follows that we'd have more hailstorms in that pattern, too.
WARMER PLANET, MORE ICE BALLS?
Paradoxically as it might seem, a warming planet might be making hail storms worse than in the past.
Hail forms when big thunderstorms create big updrafts that keep ever-growing balls of ice adding more layers of water that freezes. Finally, the hail stones get too big for the updrafts to keep them up there, so they plummet to earth.
The stronger the updrafts, the longer the hail stays up there, getting bigger and bigger. Which is why these giant things come crashing down sometimes, smashing up cars, dinging and puncturing roofs until they leak and causing other havoc.
The Washington Post picks up the story:
"As temperatures warm along Earth's surface, those updrafts may be getting stronger - and that may allow hail to grow larger before the winds can no longer keep it aloft.
The warmer the air, the more moisture it can hold. And when thunderstorms develop, a greater contrast between hot, moist air close to the ground and cold, dry air overhead can supercharge the upward winds needed to produce hail."
The Gulf of Mexico has also been abnormally warm all year so far. That means south winds blowing from the Gulf inland into the United States can grab more moisture from those waters to help intensify thunderstorms across much of the nation.
MORE TARGETS
Another big reason hail has been getting a lot more expensive is because they have a lot more targets to hit.
Big hail storms tend to strike in narrow streaks, much like tornadoes. The areas affected by hail storms are wider than those hit by tornadoes. While hail might fall in a ten or even 20 mile wide path, the worst of the hail - with the biggest stones and the greatest amount of them, only tend to fall in paths one to three miles wide.
By comparison, the widest tornadoes are 1 to 2 miles across, but those mega-twisters are extremely rare. If there's a lot of open country, a streak of wannabe destructive hail can thread the needle and avoid towns and cities.
Back in the old days, cities and towns were pretty compact. Now, those suburbs spread out all over the damn place and they keep spreading outward. That's so many more opportunities for hail stones to crash down on cars, roofs, windows, siding and such. So the costs and the insurance claims skyrocket as a result.
On top of the, climate change might (or might not, the jury is still out) be spreading big hail northward and eastward into more highly populated areas that could really get nailed.
The reason I said the jury is still out on that question is because, as the Washington Post reports, climate change might be in general reducing wind shear in severe thunderstorms. Wind shear is changes in wind speed and direction with height. Hail storms tend to thrive when the wind shear is higher.
Scientist hope to launch an intensive research project during next spring's storm season to help answer the questions about how climate change affects hail and other severe storms
RECORD BIG HAIL
Last Sunday in Texas, storm chasers near Vigo Park, Texas found a hail stone that was 7.25 inches in diameter. If verified, this spiky hailstone would set the mark for the largest hailstone on record in Texas. The old record was 6.4 inches in Hondo, Texas in 2021.
For the record, the Texas hail monster wasn't the biggest ever seen in the United States. That honor goes to an 8-inch diameter hail stone that landed in Vivian, South Dakota (right in the middle of the state) on July 23, 2010. For comparison, a bowling ball is 8.5 inches in diameter.
For Vermonters reading this, our record big hailstone is pretty small in comparison. A supercell thunderstorm on July 16, 2009 unloaded a 3.3 inch diameter chunk of ice on Westford. That's about midway between the size of a baseball and softball.
We even had our own bouts with hail this season in Vermont, though the episodes were relatively minor. Hail struck areas in eastern Franklin County back on May 21. The hailstones weren't big enough to cause a whole lot of damage, except to gardens and perhaps some farm crops.
And of course, we had that half dollar sized hail down in Waltham, Vermont Friday, and a few other reports of penny sized hail the same day.
Some hail also fell across Franklin County on April 28 as a batch of thunderstorms rumbled through.
So far, knock on wood, Vermont is yet to see any hail that's too damaging. The severe weather season is young, though.
It's nearly impossible to predict a risk of hail more than a few days in advance. Any thunderstorms we see in Vermont over the next day or two will have at worst harmless pea sized hail. Most, if not all storms will contain no hail at all because they won't be strong enough.
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