Friday, July 1, 2011

Gilmer Micro-Burst in 3D

Last evening's storms that popped across East Texas produced scattered high wind and hail reports as they drifted across the area. The Storm in Gilmer was fairly stationary as the updraft grew just to the north of town.

In the image below the storm is nearing its mature state. Notice the dark reddish purple core reaching nearly 30,000 feet into the atmosphere. It is at this time that the storm is developing its hail core and soon produce quarter size hail in Gilmer.

The next image below shows the storm at its mature stage. Notice how large the reddish purple color is and how high the light blue overshooting top is, reaching 55,000 feet in the atmosphere. The image below was taken at 6:24 PM about 10 minutes before it would unleash its severity.

In the next image notice the overshooting top has disappeared. This is the beginning of the collapse of this large storm. The time here is 6:29PM.

The next image shows the hail core is much smaller. This tells us the hail the storm was holding aloft is now reaching the ground. Shortly after this image quarter size hail was reported in Gilmer.

The next image shows the core is not only shorter, much much skinnier as well. Most of the hail at this point is falling or has fallen out of the storm. At this time the very strong downburst winds are hitting the ground as well.

The final image shows the storm in its decaying stage. The strong downburst has caused damage to parts of the downtown area of Gilmer. It has also cut off the updraft to the storm causing this storm to end but sending an outflow boundary south which will give birth to new storms.

There were two other severe micro-bursts across East Texas Thursday evening. All showed similar appearance on radar. Anytime we have surface temperatures around 100 degrees, any storm that develops could produce very strong winds. We will be watching the radar closely to see if we see a repeat tonight.

1 comment:

Steve in Wylie said...

Hey Grant, where were the storms on Tuesday night? Our family was driving back to Dallas from Gilmer on Tuesday evening, and as we were going through Hawkins and Mineola on Highway 80, we experienced strong winds from the north (an outflow?), and could see storms to the north. We came across two downed trees on 80 east of Mineola, including one that completely blocked both westbound lanes, and there was also plenty of dust and debris blowing across the highway. We kept going, and managed to drive out of it by the time we got to Grand Saline.

I read the story on the Longview News-Journal's Web site about "more storms" last night, but I went there looking for information about Tuesday night's weather.

We experienced a pretty good microburst at our house in Wylie on May 24th, one that blew down the fence in our backyard.