2012-10-13 REPORTS: KS/OK/TX

[Jeff Snyder]

Well, that was a tremendously underwhelming chase. We deployed (with RaXPol) twice, but the data are probably pretty uninteresting. Nearly all of the convection-resolving models (4 km EMC WRF, 4 km NSSL, and various HRRR runs) that I looked at only showed scant areas of weak updraft helicity for nearly all storms in OK during the day. The biggest concern I had for today was destabilization given widespread stratocumulus and showers that moved through central OK during the late morning and early afternoon. However, vis sat showing some insolation occurring west of the initial round of showers and weak thunderstorms, and surface obs showed temperatures responding (with 78-84+ F temps in southwestern OK and western N TX). So, we headed southwest from OUN towards LAW. We ended up on one storm that moved from near Lawton to Cement, but it had a flat, featureless base and looked poor on radar. With more semi-discrete storms to the S, we opted to re-target a storm SW of Lawton. By the time we got in position for this storm, there were more storms developing to the immediate S of our target storm. We watched this one from just E of Lawton, but it too was relatively unimpressive. Motion at cloud base was almost non-existent. We then punted around the area between LAW and Marlow for the next hour and a half before ending the chase.

I figured we'd at least get something decent out of a strong trough pushing through the Plains with seasonably high moisture (68-70 F Td) in place, but it was not to be. The only pictures I took were right before sunset when we had a beautiful sky near Rush Springs, OK.

The 18z OUN sounding did look much better than I was expecting (>300 m2/s2 0-1km SRH, 1600 j/kg MLCAPE, etc.). Even the 00z OUN sounding looks pretty good (much better than I was expecting as we were watching mushy, low-topped trash near I44 in the 5:30-7:00 period), but it's apparent that the near-surface layer was just a little too cool to support true surface-based convection. Storms ingesting parcels primarily from 1 km AGL ended up experiencing much weaker vertical shear since much of the low-level shear was focused in the immediate 0-1 km layer. Heck, the hodograph curves counterclockwise above 1 km, with almost no streamwise vorticity in the 1-3 km layer for a surface-based right-mover, and it looks like there's more significant negative SRH for a left-mover than positive SRH for a right-mover (for storms not ingesting near-surface parcels).

Meh.

 

[Skip Talbot]

I targeted the top of what looked to be a dryline bulge indicated on the morning rapid refresh, with cells forecast to develop near the southern end of the surface low by Wichita and build south from there. Low level shear and helicity did not look great on the boundary, but that improved noticeably ahead of the boundary. I hoped that cells would track off the boundary and stay discrete long enough to develop mesocyclones. A pool of cold air aloft was hanging out in western Kansas. I hoped that this would motivate more robust updrafts and updraft stretching for an enhanced tornado threat on the northern end of the setup. Ultimatly, the cold core in western Kansas seemed like the best play (I don't know why I always get suckered away from it, just can't trust the seemingly measly parameters up there I guess) as a storm was briefly tornado warned up there. I don't think any reports came of it though. Cells did appear more robust on radar too though.

Anyway, I got on the initial development at the north end of the warm sector, just south of Wichita. I exited 35 at Mulvane and noted a cell that was in the early stages of development with a small, immature updraft base and already a rather strong forward flanking core. The updraft gusted out within a couple minutes though, never having a chance at assembling anything along the lines of a wall cloud or even a more more mature, larger rain free base. I tracked the cell east quite a ways hoping it would shed the gust front and reorganize in the strongly sheared environment, but the pea soup clouds above the cell killed the instability and it shriveled up and died. New cells fired on the cold front with the arrival of the cold air aloft, and they looked presentable on the radar with what even appeared to be a hook on the northern most. Visually, they were extremely low topped, however, and the updrafts did not last long with the cooling surface temps and worked over air. They put up some great colors, rainbows in the setting sunlight though.

Not sad I went. If you can't enjoy a photogenic bust, I think you'll burn out fairly quickly. Also not too bummed I missed the bird fart and scuddy funnels on Friday. Both days seemed quite mediocre tornado wise, but both had some very photogenic skies, and that's all it takes for me.

Here's short time lapse sequences from central Kansas of the gusting out cell near Mulvane and then the low topped stuff north of Wichita at sunset:
Watch video >

 

[Shane Adams]

Bridget and I targeted the Lawton, OK area to start, thinking that area would have the best shot at clearing post-early convection. It was fairly obvious once we were there things weren't quite going our way, with consistent low cloud cover and cool inflow winds. We observed a non-severe storm with a non-rotating wall cloud near Lawton early, and followed it northeast to Rush Springs. From there we let this uninteresting storm go, and headed back southwest to the exact same spot we'd been, to pick up the next storm moving up from Faxon. This one was severe, and had impressive structure, as it displayed a classic mothership/whale's mouth appearance. However it was obvious this storm would not be tornadic, so we bailed south in an attempt to catch the tornado-warned storm just southeast of Wichita Falls. We moved south to just east of Walters, where we turned east onto OK53 and took that through Commanche and Loco. As we went, a new storm fired between the SPS cell and us, becoming rapidly severe with extreme high winds.

We hit OK76 north of Healdton (my hometown), then turned south towards town. Just as we were entering the outskirts of town, we were hit with hard west to southwest winds, gusting upwards of 70mph, maybe more. It was hard enough that our wipers were rendered useless, as it looked like someone was throwing 5-gallon buckets of water at the windshield. I was desperately trying to get into town, thinking these winds would probably be doing some spectacular stuff to structures, but I could only go about 20mph because I couldn't even see the end of the hood. I moved over left as far as I felt comfortable doing, in an attempt to clear us of the power lines to our right, in case they came down. We finally made it into downtown, where we found Main street almost completely blocked by structural debris, from the face of a building that had been blown apart. We stopped, helped clear some of the smaller pieces out of the road, and then continued on. Below is a link to the full video (a condensed version was seen on Good Morning America early Sunday)

Watch video >

 

[Joshua Nall]

I decided to stay in Lubbock and almost waited too long to get back into the moisture. Crossed over the dry line/front just as storms started going up. Made it up to west of Lawton somewhere and hit a few storms as they came up from the SW. This was probably the most photogenic one that I saw.

Got a few lightning bolts

Ended up dropping south all the way to 70 and raced that storm Shane mentioned along there South of Hearldton and on to interstate. There was a time when that storm was bowing out a bit and it was keeping pace with me doing 65. Heavy rain in my rearview was obscuring view of the road behind me. Clouds pushed along there just head of the rain looked to be on the ground. I then see several emergency vehicles headed West from Ardmore so I figured it tore some stuff up. Following picture is when the storm was surging out at around 65 MPH.

After dark lightning just really didn’t cooperate for me. Total miles in two days: 1,520. I really enjoy the timelapse stuff and have been inspired by others this past year to set the camera up and take a hundred or so shots with out moving it to do some short timelapse maybe. I have around 5 or so sets of images to practice with now. If I would just go ahead and commit to buy a decent computer and learn some software. Huge learning curve for me. Anyway, and looking back I learned some stuff, instead of trying for lightning ahead of the storms at dark I should have got on the backside for some sunset color and possible rainbows, lightning, etc... that might have been coming together there.

 

[Jason Young]

Like most I targeted SW Oklahoma , got to area in enough time to see odd feature hidden in heavy rain just north of the Rain free base in the Randlett / Taylor area . By the time we got to good viewing spot the storm to the south had chocked the cell of warm air and the feature was gone . ( If anyone saw this please let me know) . Dropped east on HWY 70 then down hwy 81 to try to catch the Tornado Warned cell coming out of Petrolia , Tx. but was caught by the cell between the river and Ringgold , Tx. The leading edge of the cell was almost on the ground , saw a few brief funnels , but cell quickly past us and we foolishly moved north to HWY 70 instead of dropping down to HWY 82 and missed the Saint Jo warning . Gave up in Ardmore and headed home . Happy to chase in Oct. , but ready for 2012 to be over

 

[Jeff Duda]

Based on the NMMB's fire weather nest run, I was prepared to drive up to Enid for Saturday afternoon. However, when I saw initiation appear imminent in far SW OK, I knew my target would have to shift dramatically south. I was initially planning on going west on I-40 to intercept the stuff coming up from the southwest. I ended up going west on OK-39 for Binger instead. I had my doubts about the first storms when I saw them start to congeal, and their orientation relative to the boundary wasn't pleasing either. I figured storm mode was going to be a big issue, and at least for the first wave, it was. Upon reaching Binger just as the northeastern edge of the initial storms were, I was greeted with an undercut shelf with some fuzzy lowering in the distance. This seemed to greatly excite other chasers nearby, but I wasn't impressed. I gave up on that and blasted south, eventually passing though Anadarko and circling back to Chickasha as I couldn't make up my mind as to which storm to pursue. I'd see a storm look good on one radar scan, and within two scans it would gust out or weaken. After a pit stop in Chickasha, I saw a storm to the west, southwest of Anadarko, that had a hook and rotation develop quickly, and blasted west on Hwy 62 towards it. I nearly sideswiped another car on 62 when I suddenly hit a pool of water on the highway (the road was pretty flat and straight and well constructed, so this was quite the surprise) and hydroplaned at 55 mph in the midst of a nearly blinding downpour. As I neared Anadarko from the east, a definite wall cloud emerged. It had some upward motion, and perhaps some weak rotation, but after staring at it harder, it appeared that it was surging out ahead of the storm, with the resulting differential motion giving the false appearance of rotation. I tried to stay with this storm, but amazingly, I could not, even blasting down the highways at 70+ mph. I gave up after it began moving into the OKC metro. Lastly, I saw the storm by SPS go tornado warned and appear interesting briefly, so I blasted east to get to I-35 in the hopes that by the time I got to I-35, I would be able to definitively decide to pursue the storm. I gave up upon reaching Purcell, as I gained little on the storm and figured I would not make it to Ardmore in time.

As others mentioned in this thread, it seemed like the storms were outflow dominant. This kind of surprised me given how warm and humid I felt the ambient environment to be, but the soundings don't lie. I wonder if initiation was too early. Also would've been better if those first storms hadn't formed a line and worked the SW OK atmosphere over like they did.

 

[Brett Roberts]

I was never particularly excited about this day due to the relatively veered low-level flow. In seven years of chasing based in Norman, I don't think I've ever had a good chase in the southern Plains when low-level winds were not backed at all beyond 180°. Same goes for 850 mb winds that are howling out of the SW, advecting in dry air at the top of the BL. Throughout the week preceding the event, I never once saw a forecast hodograph along the dryline in OK/KS that impressed me for substantial tornado potential. I feel this is one of the few details that all of our conventional parameters fail to account for (and understandably so, because it's fairly region-specific; the same hodographs in Alabama might well have yielded at least several tornadoes, IMO).

Regardless, given the moderate instability and impressive SRH, I wasn't going to sit out an October chase close to home. Derek Stratman and I headed out around 1pm and got pretty much what I was expecting: messy, strung-out supercells with mediocre, mushy structure. We first intercepted the northernmost of the initial line of cells near Binger. Radar indicated some moderate low-level rotation at times, but visually, this area appeared buried within the core and of little use to chasers. After we'd had enough of the large whale's mouth that extended many miles ahead of the main updraft base, we dropped S, eventually intercepting a more discrete cell as it passed over Lawton.

Unfortunately, even despite the lack of interference from any other updrafts within a ~20 mi. radius, this storm struggled to maintain supercell characteristics after heading NE of town. It's possible this was due to loss of instability from earlier rounds of convection, but the similarly-unimpressive behavior of cells in NW TX to me hints that the vertical wind profile simply was not particularly favorable for long-lived supercells anywhere outside of S/C TX. Regardless, it's a darn shame to see widespread 68-72 F surface dew points go to waste in mid-October. With regard to fall chasing in the S Plains, I've come to believe that moisture is usually the limiting factor; and furthermore, that unseasonably-rich moisture return is the key to getting those rare good chase events (4 Oct 1998, 9 Oct 2001, 7 Nov 2011). In this case, moisture return was on-par with the 1998 event and exceeded the 2001 and 2011 events, which probably doesn't happen very often in the fall season.

 

[Stephen Levine]

Left the Dallas area on Saturday around 12:30 for a trip to a Wichita Falls region. Before all was said and done, I intercepted storms in Iowa Park, Wichita Falls, Henrietta and points southeast. This included driving through two tornado warned storms, photographing a wall cloud, experiencing blinding rain with visibility to a few yards, occasional lightning bolts and winds gusting to 50 MPH. The tornado warned storms were in Wichita Falls and later Henrietta. My goal was to get ahead of the storms then watch them pass off to the northeast, being aware of structure. I drove through the apparent circulation in Henrietta as wind whipped rains took a sudden shift from south to north and northwest. Then as I continued east, an immediate shift back to the south. It was an extremely eerie feeling being in blinding rain and listening to the NWS warnings exactly in my location. More photos and complete story on http://birthingyourdream.typepad.com/joyful_storm_hunting/

 

[Danny Neal]

http://nrnilstormchaser.com/121013/