Hi all,
WHOA! WHOA AGAIN! What a day!!! We had the opportunity to go into Greensburg today but turned it down in favour of a chase. It was looking pretty marginal with CAPE of 1000-1500j/kg forecast but a S’ly LLJ of 20-30knts and a weak mid-level impulse dipping down from the main upper trough to the N was producing 30-35knt westerlies at 500mb. Upper level temperatures were also quite nice with -15C at 500mb. What was interesting was the moisture levels we spotted in southern Kansas and also into the Oklahoma panhandle which saw DP’s in the mid 50’s. Given that this moisture was to advect northwards during the day, we figured the area of NW Kansas was looking quite nice. SPC had a slight risk area extending just down to Goodland with a 15% chance of hail and wind threats.
Per the earlier post, we were in Goodland, KS with TCu going up to our S, SW and NW. The stuff to the NW was bigger at the time but the stuff to the SW had more volume so we dropped about 8mi S of Goodland and didn’t move for over an hour as a nice little LP storm developed just to our SW and moved slowly NE. We got some small hail (1-1.5cm) from it as it started to take on some nice structure with a solid base area and it was rumbling away nicely up in the anvil. It intensified rapidly when it was just to our S and the precip area thickened up a bit. It put down a little RFD which cut into the base and a small wall cloud developed and showed evidence of weak rotation for about 15 minutes or more. The cell became more of a precipitator and took an east turn at this point and we watched from the west as long as we could until the base started to become obscured (road options were limited). Shortly after this, SPC put out a Severe Thunderstorm Watch box for the area we were in, extending just south of Goodland to where this storm was.
Looking at radar and visually, you could see it was moving ESE now so we headed back up to I-70 and east to Levant, KS where we then dropped S to about 7mi N of Winona where we set up for another 35-40mins or so. The storm had hardly moved (it was doing about 10mph) but was edging slowly SE towards us! This is when things became really nice. As we were dropping S from Levant, we could see a nice inflow band coming in from the S into the base (which was off to our west) but it wasn’t until we stopped that we could see the motion in this inflow band – it was RACING northward into the storm. I’d estimate around 30knts – no less! The storm rapidly became HP and developed striations and showed clear evidence of rotation (later confirmed by SPC who indicated it was a supercell in their warnings) and was now moving SE! The mid level curved banding was incredible and the lighting (not lightning) was also just awesome! Then…just in case this wasn’t enough...IT DEVELOPED A BEAVER TAIL which aligned itself ESE/WNW into the bottom of the striated base! Can you believe this? We still can’t!! Under the beaver tail was orange from the setting sun, the core of the storm was green, there was blue sky out to the SW and then the inflow band, updrafts and striations in various shades of grey!! The structure on this storm rivals that of May 22nd in Kansas in my opinion! Just unbelievable!
Eventually the storm encroached out location but we were able to move about 4mi S and we were in the clear again to watch as the storm put out a last ditch effort to produce something. It wrapped up (for about the 3rd or 4th time) and had some nice rotation but there just wasn’t enough there today to get the job done (although we aren’t complaining after the awesome structure). Several times during its life, the cell had genuine (weak) shear indicators on the Mobile ThreatNet and there were several times where it showed estimated hail sizes of up to 3 inches and cores of up to 70dbz! We’ll have to check any reported hail sized but I’d expect at least golf balls to have been reported from this given the shear profile, moisture profile and also the upper level temperatures.
Pictures here…
http://macca.bsch.au.com/gallery/20070525On a side note, it took us over 2.5 hours of watching this storm to see any other chasers and I think in total we saw 6 or 7 other chase vehicles. You’ve gotta love these high plains surprises! Everyone was sensible apart from one person (who is lucky I cannot remember his name) who proceeded to follow chasers around and then TWICE parked his car right across the south bound lane of a relatively narrow country (sealed) road. It did not matter that there was very little traffic using the road, it was just plain stupid. There has been quite a bit of negative publicity for chasers over here lately with the number of chasers on the road and their inability to obey road laws and also common courtesy to other road users. This was a PRIME example of why chasers are getting this publicity and I do not believe this guy was a chaser as such. Keep this in mind if/when you are chasing anywhere in the world…there are ALWAYS places to pull off the road completely.
Thanks must go out to Jimmy for suggesting that this region could be worth watching today and also to our support bands being Foo Fighters, Offspring, Rage Against the Machine, Jane’s Addiction, Wolfmother, and Guns ‘n’ Roses.
Macca & Chris…totally stoked!