Green Sky Chaser

17 April 2009 Chase Log


VIDEO (opens to YouTube)

Target Area: Wichita Falls/Vernon, Texas

Chase Area: Vernon, Texas to Altus/Lawton, Oklahoma

Observations: four or five funnel clouds, three or four wall clouds, one supercell, hail, hail fog, and lightning

Distance: 470 miles

Time: 9.5 hours

Chase Team: Dean Narramore, Rob Warren, Pete Argyle, and myself

SPC Convective Outlook: Slight Risk (Click to see SPC products, data, and storm reports)

Chase Setup: Nearly vertically stacked cyclone over northeastern New Mexico, with a cold front extending north up through eastern Colorado and an occluded front/dryline through the Oklahoma/Texas Panhandles. Low instability and weak vertical shear forecast, but instability expected to increase with afternoon clearing. Winds also expected to back to east/southeast along the occluded front. Slight chance of supercells with large hail from the triple point to along the front in the eastern Texas Panhandle and western Oklahoma. Dewpoint values once again lower than desired, but still some chance of a tornado or two.

Chase Log: On the previous night, Dean and I ate a late dinner at Subway in Vernon, Texas, on the way home from our storm chase. The next day, somehow we wound up back in Vernon for a late afternoon meal at KFC (across a parking lot from the Subway!). I thought it was quite funny that the guy who took my order at KFC remembered us from the night before (though I didn't remember him). He asked me - "are you traveling or something? I saw you guys over there at Subway last night!" I told him we were storm chasers, and of course I then got the requisite questions about what the weather was going to do. We then sat out in the parking lot for a while, worried that storms would not fire. Dean said he'd get worried if there were no storms by 5 pm. The first nearby storm fired at 5:10 pm.

We followed the soon-to-be supercell back up into southwest Oklahoma, where we saw the best rotation of the season so far. The supercell cycled through several wall clouds. Many scud fingers dangling from the wall clouds tantalized us, but only about four or five of them rotated tightly into well-defined funnel clouds. I think the main problem was not enough low-level moisture, as fairly tight rotation was abundant.

Unfortunately a river with no bridge stopped us from pursuing the storm very far, but at least we didn't have to go through the disappointment of missing a tornado. There were only two tornadoes this day and they were both in eastern Colorado.

On the way back we drove through some small hail and quite a bit of hail fog. We also saw some very impressive cloud-to-ground lightning strikes, some of which were very close to the car. Dean told me in Australia they call close CG strikes (within about 100 m or so) followed by immediate thunder "flangs", a contraction of "flash bang".

So all in all it was a really good day; everything but tornadoes, but the everything was pretty good! At this point we were 2 for 2 in 2 days in a row in rotation, lightning, hail, and hail fog, with another chase day coming up the very next day.


VIDEO (opens to YouTube)