Hail the size of ping pong balls has been reported in Bourbon County in southeast Kansas, and a tornado warning has been issued in northwest Arkansas.

Widespread street flooding is being reported in Parsons, and nickel-sized hail has been reported in Labette County.

The thing I can’t figure out, though — and it’s kind of a “speaking the obvious” thing. But why is hail cold? I get that it’s ice. But it was 85 degrees last night. What’s going on up in the sky to not only turn water to ice in midair, but also make it cold? I’m sure it has something to do with atmospheric pressure or something like that, but it’s one of those things that seems obvious yet no layperson really has an answer for.

Actually, Jeff, there is an answer. Hail is cold because it’s ice. Hail is ice because it forms in layers of the atmosphere where the temperature is below freezing. As the ice crystals are buffeted around in the upper levels of the thunderstorm, they gradually accumulate moisture that also freezes, making the stone larger.

The stones fall toward the earth, but if the updrafts in the storm are strong enough they’ll push the stones back up into the upper levels again, where the process repeats itself: moisture attaches itself to the stone and freezes, making it even larger.

Eventually, the stones become too heavy to be kept aloft, and they fall to the ground. The larger the hail stones, the stronger the updrafts aloft in the thunderstorm.

That’s why large hail is one marker of an impending tornado: the same updrafts that make the large hail possible can be an ingredient in the formation of a tornado – though not every thunderstorm that produces hail is capable of developing a tornado, and not every tornadic thunderstorm has hail in it.

The temperatures near the surface of the ground – where we are – have no real bearing on the formation of hail. They merely have a say on how quickly the stones melt.

So much hail fell in my neighborhood near the Delano neighborhood that it looks like it snowed on my balcony. The stones were so large – as large as golf balls and ping-pong balls, with much of it the size of marbles – they shredded the screen door and pounded the patio door so hard I was afraid it would shatter. I almost had to shout to be heard.

The thunderstorm was moving east, so much of Wichita is going to feel this storm’s wrath.

One of them touched down briefly only a few miles northwest of Greensburg, which was decimated by an EF5 tornado two years ago. No damage was reported with Tuesday night’s tornado.

Earlier in the evening, two tornadoes were reported in southeast Kansas – one about 5 miles south of Fort Scott, and the other 8 miles southeast of Humboldt. No damage has been reported from those tornadoes.

There were more than 30 reports of hail around Kansas from the thunderstorms that formed, SPC records show.

Supercell thunderstorms capable of very large hail and strong tornadoes could develop in Missouri and southern Illinois, forecasters caution.

The atmosphere in Kansas and Oklahoma will be very moist and unstable as well, promoting the development of large, slow-moving thunderstorms. Heavy rain and hail are the primary threats, but the SPC warns “some potential will also exist for isolated tornadoes…mainly after dark.”

Given the timetable provided for local forecasters, that threat seems most likely for southeast Kansas – not the Wichita area.

The hail could be as large as baseballs, the weather service warns. If you have a garage or other way to protect your vehicles, use it.

The strong storms could continue through Friday morning before shoving east, forecasters warn. Tornadoes are not considered a threat with these storms.

“The thunderstorms will ignite from north-central Texas to eastern South Dakota with the strongest storms holding off until the afternoon and evening. Wichita, Kan., and Oklahoma City will both be in the line of fire of storms during the evening.

Overnight storms will shift farther east, threatening Omaha, Neb., Kansas City, Mo., and Dallas, Texas. The mid-Mississippi River Valley and the Arklatex Region will have dangerous storms on Tuesday, including Little Rock, Ark., and St. Louis., Mo.

Threats with the storms will include tornadoes as well as damaging winds greater than 60 mph and hail up to the size of golf balls. The greatest risk for tornadoes will be over central parts of Kansas and Oklahoma. A few of the tornadoes will be long-lived, increasing the threat of destruction.

Residents across the Plains are strongly urged to monitor local news outlets and take immediate action if a severe thunderstorm or tornado threatens. Weather radios should be left on overnight to keep alert of this dangerous weather event.”

The Storm Prediction Center has much of Nebraska and a healthy chunk of the Sunflower State under a moderate risk for severe weather today. Forecasters say the primary threats are damaging winds and large hail — much like the storms in southwest Kansas on Monday.

Storms in and around Garden City produced several reports of hail the size of ping pong balls, but one report mentioned a hail stone more than four inches in diameter. That’s larger than a grapefruit.

Large hail, damaging winds and tornadoes are possible, forecasters say. Keep an eye on forecasts and be prepared to take appropriate precautions.

Thunderstorms dropped hail bigger than softballs in some places and as big as baseballs in others. Tornadoes hopscotched north of U.S. 24.

A damage assessment team from the Hastings, Neb., branch of the National Weather Service determined that one tornado touched down about four miles north of Beloit near K-14 early Friday morning and moved northeast. It traveled about 15 miles before lifting three miles south of Jamestown in Cloud County.

At its widest point, the tornado was at least a half-mile wide. The survey team estimated that the tornado had winds of up to 115 miles an hour, making it an EF2 on the Enhanced Fujita scale.

Mitchell County Emergency Management Director Scott Davies said 7 homes were damaged – three severely – and numerous farm outbuildings were destroyed. Fortunately, no injuries were reported.

For anyone who’s wondering, hailstones as big as baseballs could be fatal if they hit someone in the wrong place.

“Those hail stones are falling at close to 100 miles an hour when they hit the ground,” said Chris Bowman, a meteorologist with the Wichita office of the weather service.

By the way: if anyone has photos of the storm damage (or the hail stones) and would like to share them with us, e-mail them to me at sfinger@wichitaeagle.com.