Heat Burst in Hastings, NE

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This morning around 4am, a thunderstorm induced a heat burst in Hastings, NE raising the temperature from 85F to 97F in a matter of a couple hours. Lincoln is definitely feeling the heat today as well with a predicted high of 95F-100F this afternoon. This quite a difference from the summer we've been feeling so far-- the kind of late spring where we were still wearing jackets. I think we'll be missing our jackets very soon!

From seeing this Hastings heat burst report I became more curious about the exact definition and what drives them. (I had forgotten from my meteorology classes) The following is a really great explanation of heat bursts from Wikipedia and I thought I would share with my blog viewers.

"In meteorology, a heat burst is a rare atmospheric phenomenon characterised by gusty winds and a rapid increase in temperature and decrease in dew point (moisture). Heat bursts typically occur during night-time and are associated with decaying thunderstorms.[1]

Although this phenomenon is not fully understood, it is theorized that the event is caused when rain evaporates (virga) into a parcel of cold dry air high in the atmosphere making the air denser than its surroundings.[2] The parcel descends rapidly, warming due to compression, overshoots its equilibrium level and reaches the surface, similar to a downburst.[3]

Recorded temperatures during heat bursts have reached well above 90 °F (32 °C), sometimes rising by 20 °F (11 °C) or more within only a few minutes. More extreme events have also been documented, where temperatures have been reported to exceed 120 °F (49 °C). However, such extreme events have never been officially verified. Heat bursts are also characterised by extremely dry air and are sometimes associated with very strong, even damaging, winds."

 And there you have it, now you know why a heat burst occurs and you have added it to your wealth of knowledge with the quest of becoming more weather-wise.