Around 9 am on Wednesday, some rain showers moved through Omaha. Seems ordinary, right?
Then things got interesting. When the rain stopped, the wind began to pick up, then it got hot...unusually hot.
At the Millard Airport, the temperature at 8:15 am was 74 degrees, a standard summer morning.
By 8:35 am, the temperature had jumped to 86 degrees, 12 degrees warmer in 20 minutes!
At 8:55 am, it had reached 90 degrees, the standard summertime afternoon high temperature, at 9 am.
Other cities experienced similar occurrences: Offutt AFB in Bellevue spiked from 75 to 91, Plattsmouth from 73 to 87, Glenwood IA from the mid-70s to 88.
What is going on? Parts of the Omaha metro experienced a rare 'heat burst'.
Here's what causes this. When a thunderstorm begins to die, the rain starts to evaporate midair. The rain-cooled air increases in density and starts to fall faster. Once the rain evaporates, the air stops cooling and begins to warm. As it continues to head toward Earth, the air gets compressed, heating it up more until it slams into the ground.
Heat bursts cause a sudden gust of wind and a dramatic spike in temperature. These usually occur at night over the Great Plains, but can happen anywhere that conditions warrant.
Most heat bursts can rapidly warm the air by 20-50 degrees, but there are extreme examples. In 1960, a heat burst in Kopperl, Texas, saw winds up to 75 mph and the temperature spike from 70 degrees to a whopping 140 degrees! (NOTE: the 140 degrees was estimated, and not officially recorded). Residents described the feeling as "sticking your head into an oven." The event is known as "Satan's Storm" by local residents.
While the heat burst experienced Wednesday morning in Omaha was nowhere close to that, it still brought quite uncomfortable conditions at 9 am on a Wednesday.
