Saturday, August 13, 2011

Heatburst

There have been quite a few heatbursts in Oklahoma this year, and one occurred last night here in Norman. What is so fascinating about these heatbursts are the variety of signatures they produce ranging from 10 to 180 minutes of strong temperature rises and dew point falls, to weak temperature rises and strong dew point falls, gusty winds, and strong pressure falls.
Note the two heat bursts from Norman between 4 and 5 am having increased the temperature by 10F from 70 to 80 over that 45 minute span. Notice how long the episode is but how sharp those peak temperatures are. I also found it interesting that the pressure drop was 4 hPa with wind gusts to 30 mph just preceding the first burst, but a lack of gusty winds on the higher temperature heatburst with a pressure rise.

I was curious if the NSSL-WRF had a similar feature but I could not zoom into the old forecast graphic to see anything so sharp in the temperature field, but there were strong dew point drops for a similar area. This suggests that this event had some predictability. Further analysis awaits.

Much credit is due to the Oklahoma Mesonet for collecting this data, and the citizens of Oklahoma for supporting such science activities.