All posts by tornatrix

Mississippi kite release

Weather

Just a quick update on the Mississippi kites I blogged about a few weeks ago. Wildcare, after taking in more than 400 of them in the extreme heat, released the last group in a public event yesterday afternoon. My name was one of the first ones drawn to release one of the kites, and I made it into this video news story from the Daily Oklahoman:
http://newsok.com/multimedia/video/1818632656001
The experience of releasing one of the kites that I had volunteered so many hours to feed was gratifying. Rondi and her staff did an amazing job accommodating and caring for all of them, and they released 85% of the kites in time for their annual migration south. Whenever I hear a Mississippi kite’s distinctive “ke-keeeer” in the sky above me, I can’t help wondering if it’s one of the brood I helped feed.

Review: And Hell Followed With It by Bonar Menninger

Media, Review

And Hell Followed With It by Bonar MenningerIt should come as no surprise to anyone that books about historic tornadoes often pop up on my Amazon recommendations. I’ve probably read two dozen of them. They’ve ranged from drama-rich to science-poor to saltine-dry, with the occasional pompous self-promotion (usually written by a television celebrity) thrown in for good measure. So when Bonar Menninger’s And Hell Followed With It: Life and Death in a Kansas Tornado (2010), about the 1966 Topeka, Kansas F-5, surfaced in my recommendations, I held off on it for a few months. I finally bought it to read on my recent trip to France. I’m pleased to say it was a solid investment that I thoroughly enjoyed.

I offer the following review with the caveats that (1) I read the Kindle edition, and (2) I have no immediate mechanism for evaluating the accuracy of many of the anecdotes. I assume implicitly (and perhaps naively) that the stories have been recorded and conveyed faithfully. However, the extensive list of references (more than 100 of them) at the end of the book gives me some confidence that the author did his homework.

It’s rare that an author comes along who is capable of weaving together a comprehensive narrative of natural calamity in a manner that doesn’t reduce the victims to near-anonymous disaster fodder (and the scientists studying the event to bookish fools, for that matter). From page one, each person who experienced the tornado is incarnated for the reader – usually via an anecdote not involving the tornado, and more often than not a humorous one. We learn about the fiery Mexican housewife, the Depression survivor caring for his disabled children, the up-and-coming disc jockey, and the 8-year-old boy frantically bicycling to a nearby store to run an errand as the tornado bears down. Details as seemingly mundane as what songs or news stories played on the radio, or what TV programs people planned to watch that night (Lost in Space, anyone?) serve to ferry the reader’s imagination back to 1966. The people described could just as easily have been a reader’s (grand)parents, relatives, friends, or neighbors.

Though the stories jump back and forth in time, Menninger masterfully braids them together to provide context for the disaster while describing the disaster itself. (The book contains a handy index at the end, enabling the reader to cross-reference each person, place, and concept.) We learn the history underlying the Burnett’s Mound myth, and about Richard Garrett’s tireless crusade to leverage the pre-existing Cold War knowledge and infrastructure (read: sirens) to prepare Topeka’s citizens for a tornado that he was sure would come someday. Garrett’s efforts in particular are credited with holding the number of tornado fatalities in his state’s capitol down to just over a dozen, for which he received an Exceptional Service Award from the U.S. Weather Bureau.

There’s also the saga of John P. Finley’s 1880s tornado research, the Weather Bureau’s subsequent ban on the use of the word “tornado” in its products, and the redemption provided by the 1948 Fawbush and Miller tornado forecast. Despite the book jacket’s claim that the above story is “virtually unknown,” it’s old yarn to me. That’s not just because I’m a severe weather researcher, but because that story is inevitably retold in just about every contemporary tornado book I’ve read! But that’s a minor gripe about the promotion, not the writing.

Accounts of the tornado’s destruction – chapter by chapter, block by block – never become repetitive. The stories are still just as compelling, and the dread just as fresh and palpable, in Chapter 15 as in Chapter 1. The last couple of chapters deal with the aftermath on scales ranging from personal to national. We learn the fates of the survivors, some of whom had to deal with the physical and mental trauma, in some form or another, for the rest of their lives. Some even report bits of debris still emerging from their skin 20 years later!

From a meteorologists’ perspective, I could not find much to complain about. The highway overpass myth is firmly dispelled at several different points in the book, including the forward. (Several victims encountered the tornado along I-70.) Menninger does a decent job of articulating the state of severe weather science in 1966, and how newer insights have helped to illuminate the events described. However, many of the meteorologists profiled are now deceased, and I did not have the pleasure of meeting them. Perhaps some of my readers can offer their insights as to the accuracy of their stories.

Topeka tornado mural
This mural, “Tragic Prelude,” inside the Topeka state capitol rotunda, vividly depicts the tornado as a metaphor for Kansas’ turbulent history. (This is not the actual mural, which was closed for cleaning when I visited, but a photograph of it.)
What really impressed me about And Hell Followed With It was the quality of the writing. The tornado is variously described as an “enormous, whitish-gray basket,” a giant “broadcast spreader” or “lawn mower,” “boiling, gray lava,” “an ancient, crooked finger,” “coiled like a snake” (during its rope-out phase), and so on. The book reads like a work of fiction, so fast and thick do the metaphors come, and so vividly are the people portrayed. Alas, the Topeka tornado was very real, and as I found out on my visits to Topeka during VORTEX2, the city is loathe to forget.

Lay readers, disaster buffs, and professional meteorologists alike should find something to appreciate in And Hell Followed With It. The author has done a remarkable job of aggregating a colossal amount of information about the Topeka tornado and conveying it in a narrative that is digestible, compelling, and sometimes even funny. And Hell Followed With It should set a standard against which other comprehensive tornado histories can be judged.

Hot topics

Weather

After getting off to a comfortable start with slightly above-average rainfall, summer returned with a vengeance to our neck of the woods. Our lawn, once lush with growth, is now mostly brown and crispy underfoot. I cycled home on Thursday evening crossed by a withering, 111 oF southerly wind. Friday, our 16th consecutive day with a maximum temperature greater than 100 oF, saw the introduction of a statewide burn ban as winds gusted to 25 mph. I crossed my fingers that the firefighters would stay bored, but unfortunately a smoke plume appeared southeast of the NWC around lunchtime.

Lake Thunderbird pyrocumulus
Pyrocumulus cloud over Lake Thunderbird around 5 p.m. on 3 August 2012.
By 5 p.m., the fire had crept northward toward Lake Thunderbird State Park and expanded. The primary smoke column was crowned by a crisp pyrocumulus cloud – the tallest I’d ever seen at a height of greater than 4 miles. Jim LaDue captured a time lapse video of this pyrocu that clearly shows it pulsing upward in response to the thermal plumes from the fire. (Hard to believe anything could be positively buoyant in this heat, but there you go.)

As evening fell, we saw an orange glow on the eastern horizon, like a false dawn, as we walked our dog around the block. We had “grab and go” bags packed just in case the fire decided to get ornery. Fortunately, it remained well east of our neighborhood. However, several of our friends living farther east, along the south shore of Lake Thunderbird, did have to evacuate for a time. The overnight diligence of firefighters kept the flames off their doorsteps. Other people living farther east were not as lucky.

An even bigger fire erupted northeast of Oklahoma City and destroyed significant swathes of Luther, OK. The outrage over the apparent act of arson that started this fire made national headlines. And the danger’s not over – Another week of 100+ oF high temps is on tap, but not a drop of rain in the offing.

Mississippi kites at Wildcare
Hundreds of fledgling Mississippi kites, forced out of their nests early by the heat, fill enclosures like these at Wildcare in Noble, OK.
Apart from exacerbating the tinder-dry conditions, the hot weather is also impacting local wildlife. In a repeat of 2011, dozens of fledgling Mississippi kites are jumping out of their nests prematurely to escape the scorching sun. Once on the ground, the parents don’t feed them (enough). In our area, these sort-of-orphans typically end up at Wildcare. The kites don’t require much, but the sheer juvenile kite numbers this year (300+), as last year, have overwhelmed Wildcare’s small staff. I’ve volunteered for a few shifts feeding the kites bits of meat with a forceps and spraying them down with a hose to keep them cool. (They don’t mind the jet of water from the hose. In fact, they open their wings to embrace the spray!) Most of them will be ready to release by 1 September.

I grew up in Minnesota, where we have a certain machismo about winter: bragging about how low the wind chill was while we waited for the bus, how tall the snow drifts at the end of the driveway got, etc. Winter is a fact of life, and we’ve learned to live with it, even celebrate it. I’ve lived in Oklahoma for 10 years now, and found the exact same to be true of Oklahomans and the oven outside. Heck, I’ve even come around to join then. (“Whoa, you cycled when it was how hot?”) Nonetheless, I’m looking forward to the more temperate days of fall. Believe me, they can’t come soon enough!

New pub

Chasing, Radar, Research

I’ve got a paper in this month’s Monthly Weather Review entitled Mobile, X-band, Polarimetric Doppler Radar Observations of the 4 May 2007 Greensburg, Kansas, Tornadic Supercell. This is the first of two planned papers based on my Ph.D. research, an observational study based on UMass X-Pol data that we collected in the Greensburg storm.

UMass X-Pol on 4 May 2007
UMass X-Pol on 4 May 2007. Had it not been for the blown tire, we might not have collected data in the Greensburg storm.
Operations on 4 May 2007 started off on a low note. Howie, Kery H., and I were driving the UMass X-Pol to Dodge City, Kansas on our first chase of the season, when we blew a tire. With the aid of a good samaritan who just happened to have a spare that was the right size, we limped into Protection, Kansas. Tornado reports near Arnett, OK tempted the rest of our group back south, and we figured we had a bust chase on our hands. As soon as the new tire was on, a storm erupted southwest of Protection, and we decided to collect some “consolation data” in it and shake down the system.

A local sheriff showed us to his favorite storm spotting place on a hill looking over Protection. That road was too muddy for us to use, so we moved about two miles east and deployed on a packed gravel road. As we lost daylight fast, the storm dropped a rotating wall cloud, followed by a brief tornado and an additional funnel cloud to our west. We got volumetric, polarimetric X-band data of all these features. At one point I had to back the truck up to avoid beam blockage from telephone poles along US Hwy. 160, resulting in a small gap in the data.

The Greensburg tornado (#5) illuminated by lightning. These are frame grabs from my handheld video.
The Greensburg tornado (#5) illuminated by lightning. These are frame grabs from my handheld video.
As night fell, we lost visual on the wall cloud, but the radar presentation showed a giant spiraling hook echo. We were certain there must be a tornado occurring, so we kept collecting data. We had barely any reception of weather radio, but between the lightning crackles we could make out a series of urgent tornado warnings on our target storm issuing from the NWS office in Dodge City, including indications of a large tornado. Occasionally, flashes of lightning outlined a large lowering in the cloud base to our north (see images at right). After collecting more than an hour of data, we finally shut the system off around 9:30 p.m., when the deep-cycle marine batteries on board the UMass X-Pol, used to power the antenna pedestal and computer, completely drained.

En route back to Norman around midnight, congratulating ourselves on a great first deployment of the season, my cell phone rang. Chip L. had been chasing with us earlier in the afternoon, but split off after our tire mishap. “Greensburg has been completely destroyed,” he said solemnly. As an EMT, he had gone there to assist, and witnessed near-complete devastation of a town of ~1500. We stopped at a fast food restaurant in Ada, where a TV screen in the corner of the room flickered images that looked like they’d come from a war zone. The remainder of the drive back was much quieter and more somber.

Reflectivity, Doppler velocity, and storm-relative Doppler velocity data in the Greensburg tornado
Reflectivity, Doppler velocity, and storm-relative Doppler velocity data in the Greensburg tornado
Over the next few days, back in Norman, I pored over the data, and it quickly became clear that this would be my dissertation case. We had captured not only the genesis of an EF-5 tornado, but several weaker, antecedent tornadoes. In trying to figure out why the Greensburg storm changed tornado production “modes”, a wealth of information offered itself up, and that information forms the basis for this paper. Other scientists, most notably Jana H., Howie, Mike U., Jeff H., contributed data, discussion, and analysis to the study. Two anonymous reviewers also helped me to sculpt the messy initial version into something clearer and more concise. (Word to the wise: Don’t just copy-and-paste half of your dissertation into a journal template and submit it. I was lucky the first version didn’t get rejected outright!)

In the years since that night, I’ve driven through Greensburg several times, and have been continually amazed by the community’s resilience and resurgence. When the time came, I dedicated my dissertation research to all the victims of the Greensburg tornado. Although improved scientific understanding can never undo the pain to the Greensburg community, I’d like to think that this study was one small, positive thing that came of an otherwise wholly devastating event.

No Time Toulouse

Radar, Research, Travel

Météo France's Toulouse C-band radar
Météo France's Toulouse C-band radar
Sorry it’s been a little quiet around here over the last month, but I think I had a good reason. I was getting ready for my first European radar conference: 7th European Conference on Radar in Meteorology and Hydrology in Toulouse. I’d never set foot in France before, and wanted to put my best one forward!

At the Météo France conference center, I presented a talk (about GBVTD analysis of W-band data we collected during VORTEX2) and two posters (both on EnKF assimilation of mobile radar data in supercells). I reconnected with domestic and international colleagues, as well as making some new acquaintances. Between sessions, we had receptions and banquets at several Toulouse landmarks, including City Hall and the 800-year-old Hotel Dieu.

Poster session at ERAD 2012
The poster session of ERAD 2012, held in an air-conditioned tent.
I got to see updated versions of some research presented at last fall’s AMS Radar Meteorology Conference in Pittsburgh, as well as some intriguing new work from my European contemporaries. (There weren’t many tornado talks, but there aren’t as many tornadoes in Europe, after all!) On the final day, there were a couple of talks about radar-based aeroecology (detection and characterization of birds, bats, insects, etc.). Fascinating stuff. Biologists are finding gold in the data that we usually ditch in QC!

An evening stroll down the streets of Toulouse
An evening stroll down the streets of Toulouse
Outside the conference, downtown Toulouse was visually pleasing and gastronomically amazing. I took relaxed strolls through the streets and gardens in the evenings, admiring the wrought iron balconies and old chuches, nibbling cheese, and sipping wine. Oh, and taking in Euro Cup matches with the locals, too! The people were, by and large, friendly, and most of the waitstaff at restaurants spoke enough English to get our orders right. I visited 13th-century cathedrals, open-air markets, stunning museums, historic hotels, and verdant gardens.

I figured out early in my stay that I couldn’t possibly pack in all the activities I wanted to do in one week. It’s just as well, because I kept getting lost! And of all the cities I’ve visited, Toulouse was by far the best city to get lost in, slow down, and enjoy.

I’ve returned to find summer baking Oklahoma in earnest. It may not be too long before we dust off the dust devil chasing gear again!

2012-05-30: Paducah, TX landspout

Chasing

Paducah, TX landspout at about 5: 30 p.m.
Paducah, TX landspout as seen from U.S. Hwy 70 at about 5:32 p.m.

On 30 May 2012, I had the honor of tagging along with the NOXP radar (with my husband Dan D. and Ted M. as crew), operating in support in of the Deep Convective Clouds and Chemistry Experiment DC3). Although the morning’s SPC outlook highlighted a SW KS-NW OK corridor for severe thunderstorms, some of the high-res models indicated that there would be an earlier outbreak of storms along the dryline in the E TX PH, in response to a developing cyclone and robust moisture return. Any cold pools laid down by the storms in Texas had the potential to muck up the Oklahoma target.

Horizontal convective roll over Elgin Air Force Base near Altus, OK
HCR over Elgin AFB near Altus, OK
We set out from Norman shortly after lunch and headed southwest to Altus, where we were greeted by some striking horizontal convective rolls (HCRs).

Farther west, storms fired off the dryline and promptly split. Right-movers tracked southeast, prompting the DC3 radars (SR1, SR2, and NOXP, led by Dr. Mike Biggerstaff) to head south out of Altus on U.S. Hwy. 283. A few participants grumbled about the choice to head south rather than take more direct route west. However, the objectives of DC3 are a bit different than in VORTEX2. Priority number one is long-duration, dual-doppler data in convective storms, so the radars set up well in advance and collect as the storms pass by. (Tornadoes are not the main focus of DC3, but they’re considered a nice bonus.)

After crossing the Texas border, thereby committing ourselves to chasing right movers, Dr. Biggerstaff decided to target the southernmost storm in the cluster, which was headed for Paducah, TX, and set up his dual-Doppler lobe on U.S. Hwy. 70 between Crowell and Paducah. As the crew NOXP’s scout vehicle (a mobile mesonet called Scout 3) drove ahead to locate a suitable deployment site and hold it for the radar truck, a few dramatic dust clouds arose on the updraft-downdraft interface, some with gustnadoes and shallow rotation. One dust tube (pictured at top) extended up hundreds of feet, almost touching cloud base. It was unclear whether it as connected to the nearby mesocyclone or shear-induced, so I’ve been calling it a “landspout” in my discussions.

NOXP deployed south of Paducah, TX
NOXP deployed south of Paducah, TX
In Scout 3, Chris S. and Blake A. located a small hilltop side road on which to deploy, and Ted M. backed NOXP into it. I bailed out of the radar operator’s seat and was nearly knocked flat by the gust front. I shot some shaky video as a second, low-contrast landspout erupted out of the field about half a mile to our east, and still another touched down almost on top of Scout 3. Just as NOXP was preparing to start scanning, I heard a sharp thump on the ground next to me, looked down, and saw a baseball-sized hailstone half-coated in red dirt. I dove into Scout 3’s back seat for cover with my camera in hand, with more large hail thumping down around us. Ted M. waved his hand in circles, indicating that we needed to undeploy and escape ASAP, as our target storm had turned hard to the right. Rather than trying to scramble back to NOXP and possibly delay our expedited departure, I simply buckled into my seat in Scout 3, and hitchhiked west with them to Paducah. As Chris put it, “Welcome to NOXP!”

NOXP reflectivity display
The Paducah storm as seen by NOXP radar at about 6:08 p.m. CDT, showing a WEH (at about 40 km range and 60 degrees azimuth) near a report of a rain-wrapped tornado.
Fortunately, both Scout 3 and NOXP escaped any direct hits from the sporadic, fist-sized hail stones, and were able redeploy on U.S. Hwy. 83 about 12 miles south of Paducah. When NOXP finally started scanning again, an velocity couplet and weak-echo hole were evident on the display. We strained and squinted, but could not make out any evidence of a tornado in the murk to our east. (NOXP’s display indicated it was buried behind a rain curtain several km thick.)

We undeployed and headed south again to U.S. Hwy. 82, where we learned that the DC3 balloon crews had stopped operating. NOXP headed back north again for a second deployment on U.S. Hwy. 83, targeting a second supercell following much the same track as the first Paducah supercell. Although the storm had a nice inflow tail, it appeared to be outflow-dominated, with a rolling dust cloud spilling out in front of it.

Mammatus under the second Paducah, TX supercell of 30 May 2012
Mammatus under the second Paducah, TX supercell of 30 May 2012
We made a last stand back to the south on U.S. Hwy. 82, watching the storm roll away to be replaced by clear skies and a golden Texas sunset. A few small low-level vortices appeared along the storm’s rear flank, but were not connected to any updraft upstairs. We enjoyed some elaborate mammatus clouds as we drove back north and the sun sank below the western horizon.

During our hasty, hail-induced departure from Paducah earlier in the afternoon, we had had to leave behind a pair of NOXP’s metal plates (placed underneath the hydraulic levelers on soft soil). As we returned to the site to retrieve the plates, we observed sporadic wind damage throughout Paducah. Garage doors had buckled inward, roof shingles and small brances were strewn across lawns, and the power in Paducah was out. A few miles east of Paducah, near the intersection of U.S. Hwy. 70 and County Rd. 301, we encountered a metal outbuilding that had been about 50% demolished by a particularly intense wind swath. Sheet metal had been peeled off and scattered to the southwest of the structure, wrapped around telephone poles and road signs up to 1/4 mile away. (I couldn’t get any photos owing to darkness.) Curiously, a second metal building across the street, a few hundred feet to the south, appeared untouched. Some very localized wind phenomenon (small tornado? microburst?) had inflicted substantial damage there.

After retrieving the plates, we made our way back to Norman by way of Childress, TX. Now in the driver’s seat, Dan fought a 70 mph head wind in Lawton, pushed out by collapsing storms dozens of miles to the north. We pulled back into the NWC around 2 a.m.

A storm chaser’s review of the Bloggie 3D pocketcam

Gear

The Sony Bloggie MHS-FS3 in hand
Can this little gadget shoot quality 3D storm video?
As a reward for submitting a long-overdue manuscript, I recently bought myself a toy: A Sony MHS-FS3 3D Bloggie HD pocket camcorder. I’ve been intrigued both by the idea of “HD in my pocket” and by the recent resurgence in 3D films. This camera is not intended to replace my Canon Vixia HV30; I intend to use it primarily to shoot 3D video of tornadoes for novelty. It also serves well as an HD dash cam, since it doesn’t weigh down my windshield suction cup mount. I tested it out on both 13 and 14 April 2012 chases.

Here’s an example of 3D video I shot on our approach to Cherokee, OK on 14 April. YouTube was smart enough to recognize the H.264 3D format.

Pros:

It’s teeny, about the size of a smart phone. It’s also fairly intuitive to use, with minimal buttons and menus. I was able to explore most of the functionality before I ever had to crack open the manual. (Owing to the small box size, the camera only comes with a “quick start” instruction card; the full manual is available on Sony’s web site.)

There’s no need to use the pre-loaded “Bloggie” software (intended to facilitate quick sharing of video via Facebook, Youtube, etc.) to offload the videos in Windows 7; the “import” function works just fine. Like other pocket cams, it interfaces with a computer via a Swiss-army-style USB 2.0 port. The viewfinder is actually a “Magic Eye” 3D display, which I find nifty. The camcorder also interfaced cleanly with our 3D-capable Samsung HD TV using a mini-HDMI cable.

The 1080 HD video and audio quality are surprisingly good. I used it on my 14 April chase as a dash cam, turning it on and off whenever something interesting came into view. The battery held out through the entire chase (although admittedly, I was rather frugal with it). My highlights reel from 14 April 2012 contains video from both the Bloggie (dash-cam shots) and my Canon Vixia HV30 (handheld and tripoded). Can you tell the difference?

Cons:

The Bloggie mounted on a tripod
Because the tripod threads are on the side, I have to tilt my tripod head over as far as it will go, then cheat a few more degrees by retracting one of the legs.
To shoot in 3D, one has to hold the camera horizontally. However, the tripod threads are located on the side rather than on the bottom – meaning you need a tripod head that can articulate 90 degrees in order to shoot level 3D video. Fortunately, the camera weighs a scant 4.2 oz, so the danger of tipping over a substantial tripod is minimal, but the placement of the threads strikes me as a serious design flaw.

The internal media only holds about 80 minutes of 1080 HD or 3D HD video. I would love to be able to expand to an SD card, but unfortunately this model does not have that option.

The 4.2-oz. Bloggie holds fast to my windshield with a standard 3-suction cup mount.
The 4.2-oz. Bloggie holds fast to my windshield with a standard 3-suction cup mount.
There are a lot of “auto-” settings, such as exposure, white-balance, and most importantly, focus. When shooting storms, I typically peg the focus on infinity. On 14 April, the Bloggie yielded a few “wet windshield” shots, but fortunately passing windshield wiper blades don’t confuse it too much. The auto-focus didn’t work very well in low light conditions, as one might expect – it tended to keep the focus on the foreground.

The Bloggie isn’t weatherproof, so you have to keep it dry. Sony makes another model called the Bloggie Sport, which is waterproof, dirt-proof, and drop-proof, but it doesn’t shoot 3D. Oh well.

At the moment, my current video editing software of choice, Adobe Premiere Elements 10, doesn’t support stereoscopic 3D editing. That’s why I had to upload my first tornado clip sans editing or copyright overlays. Adobe Premiere Pro supports 3D, but of course it is considerably more expensive. I can only hope 3D editing is on the horizon for Premiere Elements 11.

To summarize, the Sony Bloggie MHS-FS3 is a relatively cheap (<$200) gateway to 3D HD video. It could benefit from some weatherproofing, a few more user control features (particularly the focus), and affordable video editing software. However, it's something new, lightweight, and fun in my chase gear bag, and I look forward to testing it out on future storms.

2012-04-30: LP supercell near Claude, TX

Chasing

The last week of April saw the arrival of this year’s Windom High School group from southwest Minnesota, consisting of nine enthusiastic, weather-savvy seniors, their teacher, Craig Wolter, and three chaperones. Each year, Craig takes his top ten or so students on a five-day storm chasing trip to Norman, where the students get to visit the NWC and meet and greet with meteorologists there. Craig has a tight itinerary for his students upon arriving in Norman, but it can always be pre-empted by a decent chase setup. As a fellow Minnesotan, I have a soft spot for Craig’s kids, and always try to lead them on at least one chase. If there had been such a program at my high school, I would have killed to get on the trip!

2012-04-30: Claude, TX LP supercell
The Claude, TX LP supercell, around 6 p.m. The view is toward the west.
Dan and I were able to take Windom group out on Monday, April 30th, after noticing an enticing setup in the Texas panhandle consisting of a trough encroaching on an outflow boundary from the previous night’s widespread convection. Upon arriving in Memphis, TX, we found convection struggling to initiate along the dryline. We drifted northwest on U.S. Hwy. 287, toward a clump of storms west of Amarillo, intercepting it as it organized into a supercell near Claude, TX. We drove about 2 miles north off of U.S. Hwy. 287 to obtain a clear view to the west.

2012-04-30: Claude, TX "nipple cloud"
This "nipple cloud" (just left of the rain shaft) persisted for about three minutes and prompted several funnel cloud reports. We think it would have developed into a full tornado if the storm had been able to tap into deeper moisture just to its east.
We were presented with a beautiful, high-contrast LP supercell, and proceeded to point out all the salient features to the students. The high bases didn’t bother us too much, because we knew the Claude storm was drifting east into better moisture, and we expected great things from it once it began to realize the improved buoyancy. As we watched, the Claude storm split right in front of the students, allowing us to narrate the process live. I pointed out a small, cone-shaped lowering just south of the main precipitation shaft on the right-mover. It persisted for three to four minutes, but never extended more than 10% of the distance from cloud to ground.

Windom HS students watching the approaching base of the Claude, TX supercell.
Windom HS students watching the approaching base of the Claude, TX supercell.
Meanwhile, we noticed new Cbs to our east, rooted in the deeper moisture. The updrafts on the new towers were crisp and glaciated, so we kept our heads on swivels in case we needed to re-target. The Claude storm dropped a few nickel-and-dime hailstones on us, forcing us to jog east twice along our dirt road in order to keep ahead of the storm. The vault structure grew breathtaking. We were able to enjoy it in relative solitude, without any other chasers blowing clouds of dirt on us. Simply moving a mile or so off the main highway is proving a surprisingly effective way to avoid the hordes. (I think I’m going to require 4WD in my next chase vehicle.)

The Claude, TX supercell eventually became outflow-dominant, so we decided to re-target the next storm to the east (the Hedley, TX storm), whose birth we had witnessed about an hour before. We retraced our route southeast on U.S. Hwy. 287, then went east on TX-203. We thought we would be able to core-punch the Hedley storm without too much trouble as it lifted northeast, then emerge from its forward flank and with a view of the hook to our southwest. However, radar updates showed new storm cells erupting to the south of, then being ingested by, the Hedley storm. These processes interfered with storm consolidation and hook formation, and also resulted in our spending more time in the hail core than we expected, our vehicles pelted with nickels and dimes for nearly 40 minutes.

2012-04-30: At dusk: Gustnado? Tornado?
At dusk near Wellington, TX: Gustnado? Tornado? The view is toward the SW, the feature of interest at the center of the image.
When we finally did emerge from what should have been the forward flank of our target storm, crossing over the border where TX-203 changed to OK-9, it was dusk. Looking back toward Wellington, TX, we caught glimpses of the hook region to our southwest. Suddenly, Dan commanded me to stop the car, chattering excitedly about a dust cloud. I couldn’t see anything from the driver’s seat, but I stopped at the top of a hill. By the time I got out of the car and fired up my camera, the dust cloud was gone, but I could see the scud finger which had grabbed his attention. My only photo of it is very poor and I had to enhance the hell out of the contrast in order to make it visible. The feature was too brief and ambiguous, the distance too far, and the lighting too poor, for us to conclusively call it a tornado.

We took a rather circuitous route back to Norman via Lawton, attempting to avoid a southward-diving hailer over Hobart, OK. We returned to Norman around 1 a.m.

In the days since this chase, I’ve read an April 30 chase account from Bill Reid, whose Tempest Tour group (including Brian Morganti) was much closer to the ambiguous lowering than we were. Even with his close proximity, he wasn’t certain what to call the feature, and after viewing his video, I can see why. However, he eventually concluded that this dusty spin-up was indeed a tornado. Bill’s a veteran chaser, and if he says it was a tornado, then that’s good enough for me. Based on his account, I was able to report to Craig that his students were no longer tornado virgins!

Update, 2012-05-07: After looking at video from the Tempest Tours group, the NWS office in Amarillo declared our “scud finger” an EF-0 tornado. So, now, it’s officially official!

2012-04-27: Brief tornado near Council Grove, KS

Chasing

SPC 1630 UTC Day 1 Convective Outlook on 27 April 2012. Copyright NOAA.
SPC 1630 UTC Day 1 Convective Outlook on 27 April 2012. Copyright NOAA.
Parental visits in springtime are always fraught with uncertainty. We can pack our agenda for the weekend with varied activities, only to have everything unravel the minute the atmosphere starts acting up. I had poo-poohed the chase setup for Friday, April 27th, thinking that it wouldn’t be worth driving to Kansas. However, I awoke to find the forums abuzz with excitement about the shortwave trough ejecting earlier than forecast, prompting a moderate risk on the Day 1 convective outlook from SPC. Anticipating an early afternoon chase setup, my husband and I scooped my parents up from the airport, and blasted north on I-35 into south-central Kansas, where we were greeted by clearing skies and a few turkey towers along the dryline. (Mom and Dad had flown more than 800 miles south from Minnesota to see us, only to backtrack immediately almost 1/3 of the way home.)

2012-04-27: Funnel cloud near Council Grove, KS
Brief funnel cloud near Council Grove, KS. Note the clear slot illuminating the funnel.
Near Emporia, KS, we met up with Jeff S., chasing solo. The atmosphere produced mediocre convection for hours. As a surface low approached from the west, increasing the low-level shear, it also squeezed the warm sector between the cold and warm fronts. We were forced to follow the warm air up into the Flint Hills area. This region has good visibility, provided that you’re on top of one of the hills. By the time we targeted a storm near Council Grove, KS, the warm sector (and the storm’s access to the warm, moist air within) was only a few tens of miles wide, if that. Cold rain and gusts of wind pelted us as we parked on a hilltop gravel road off U.S. Hwy. 56 near Bushong, KS, watching two cloud bases to our west-northwest. Suddenly, Jeff S. shouted to our group as a small white funnel abruptly materialized within an RFD slot to our northwest. I barely had time to re-center my video before it eroded away.

2012-04-27: Tornado near Council Grove, KS
Brief tornado near Council Grove, KS. One or two suction vortices revolved around the base.
Minutes later, another funnel descended from the far bank of clouds, tickling the ground with a few suction vorticies. From my vantage point, this brief tornado dropped right behind a tree. My video consists mainly of my scrambling a few feet to the right and re-leveling my shot, by which time the tornado had already vanished. Because of the brevity of these two funnels and the shakiness of my video, I decided not to post either shot on YouTube. Screen shots it shall be.

The cold rain and pea-sized hail began to fall in earnest, driving us back into our cars. We may have glimpsed another funnel on the horizon, but lost it in the rain after a few seconds. To our north was a road hole, forcing us to head east on U.S. Hwy. 56. The remainder of our chase consisted of an attempt to catch another storm to the east of our original target. Unfortunately, it was ingesting stable air, the warm sector long since squeezed out of existence, and we decided to abandon the chase near Osage City, KS. We had dinner at Emporia, then began the long haul back to Norman.

As I’ve gotten older, I’ve gotten little more choosy about which days I chase. (I chalk part of this change up to accumulated experience, and part to having a full-time job and family to support now that I’m done with school.) However, when I have guests along, I’m more likely to bite on riskier setups with more potential failure modes. Even though it required a 5-hour drive each way, seeing one tornado is definitely better than seeing none!