Jun 042013
 

El Reno Tornado of May 31st, 2013

El Reno Tornado of May 31st, 2013

Tornado intercepting, media reporting, storm gawking, storm chasing, storm tours, storm research and storm spotting ; all of these activities involve being in the field or on the road and close to severe thunderstorms and tornadoes.  But what are the differences?  And what is considered “close”?

Let me start with storm spotting. Storm spotters form the backbone of the severe weather warning process and here’s why: these volunteers are dispatched to pre-determined locations during potentially severe weather to watch for threatening weather. Usually, spotters are in areas with good visibility and positioned in a westerly direction from towns or cities. This is of course to watch activity coming in from the west. Spotters are not chasers. The vast majority of storm spotters are HAM radio operators.  Many of them are rescue, first responders or law enforcement officials.

Storm researchers are often out during severe weather.  In my definition, this includes collecting meteorological data in close proximity of storms.  Doppler radar on wheels and mobile meso-net vehicles (vehicles with sensors on board) fall into this category.  A handful of universities have teams which go out during severe weather situations.  There are private individuals which perform research too.  Tim Samaras, who died in the El Reno tornado (along with his son Paul and another researcher Carl Young), was one such researcher.  He endeavored to place flat, disk-looking probes in the path of a tornado in order to collect pressure information and video cameras shots from various angles.

I remember watching a video presentation given by Tim Samaras at a severe weather conference.  The video showed his deployment of a probe in front of the Manchester, SD tornado in 2003.  The really amazing thing to me was after he placed the probe, he looked up at the approaching tornado, looked back at this probe, picked up the probe, ran down the road with it and placed in a better spot! All of this occurred of course while the tornado was getting closer and closer.  I still use the pressure drop data collected by “probe 3”  in my Weather and Climate lab.

Pressure Drop Measured by  a Tim Samaras Probe

Pressure Drop Measured by a Tim Samaras Probe

The scientific contributions made by Tim Samaras toward understanding the dynamics of tornado is to be honored, as is his passion for what he did and the concern he showed for the safety other chasers. He will be missed.

Storm chase tours take paid guests out into the field to chase down severe storms and tornadoes.  Some of the long established tour groups have a solid reputation for safety.  Many other have popped up recently promising a wild ride and an extreme adventure.  There are a lot more of these than there used to be. I started a formal chase tour company myself this year.  If you have read my blogs, you know my philosophy on what is safe and what isn’t. Most of these groups don’t get too close.  I sell mine on the whole experience, from forecasting to road strategy to field observation to radar interpretation.  Seeing a tornado would be great, if it can be done safely!

Storm chasers fall into a broad category. Some are out there to get great video. Some like the thrill and challenge of predicting which storms will “go” and then figuring out how to catch them.  Many are very responsible, calling in storm reports and rendering assistance to storm victims. Many chasers are essentially mobile spotters. There are many cases where vital storm reports for a given area come from chasers who might live states away.

An ever increasing proportion of chasers are casual storm gawkers who use their mobile phone for a radar screen and go. They usually don’t travel very far from home. They have very little understanding of what they are looking at. Terms like storm motion, mesocyclone occlusion or rear flank downdraft mean nothing to them (but boy are they important!)

Media chasers are both local and national.  It is common in larger television markets or those in “tornado alley” to deploy helicopters during severe weather. Many capture the tornado in action. We saw such a copter flying along the southern edge of the El Reno storm on Friday.  Of course, The Weather Channel drew a lot of attention to itself  when Mike Bettes and producer were rolled several times in their vehicle by the El Reno tornado.  They are extremely lucky to be alive.

Then there are the tornado interceptors like the Tornado Intercept Vehicle (TIV) with Sean Casey and the Dominator with Reed Timmer.  These folks drive right at tornadoes and strive to be very close if not ultimately inside of them. Now the vehicles they drive are armored, offering a great deal of protection.

Our Chase Path Relative to the El Reno Tornado

Our Chase Path Relative to the El Reno Tornado

The reason I’m going through the trouble of distinguishing between these groups is that the term “storm chaser” is used as a net to capture all of this activity. So when people say “storm chasers save lives” or “they cause road congestion” or “they set a bad example and are reckless  ” or “they are collecting valuable scientific  information”, well, some fit these definitions better than others!

Since I just started chasing storms is tour company mode and in light of the recent events in Oklahoma, I have to ask myself  “am I out there for the right reasons?” and “am I comfortable doing this?”  My answers is yes.  I feel like I am responsible and careful.

I said I would talk about how close is too close.  Generally, distance buys safety!  The farther away you are, the more time you have to react.

I do need to make a statement from a meteorological perspective: there is no reason to believe that any tornado will move in a linear or continuous sort of way!!  Mother nature gave us some ominous signs this season: Cleburne, TX and Bennington, KS come to mind.  Tornadoes near both of these cities were large, dangerous and made some unusual turns. My blog on the Cleburne tornado can be read here.

My sincere hope is that all “storm chasers” carefully consider all future chases.  Learn, err on the side of safety and remember that the entire development of severe storms is a process and a quite amazing one at that.  Appreciate the whole package!

 

 

 

 

 

 

Jun 022013
 

Rotation in Storm Near Bridgeport, OK

Rotation in Storm Near Bridgeport, OK

My guests on this chase tour were Bryan Snider from Phoenix, AZ  and Jeff Bowers from Springfield.  Jeff and I left Springfield around 9 a.m.  Bryan flew into Tulsa the day before and we picked him up along the way.  My thanks to both of them for the support, documentation and navigation help during this storm chase tour!

Anyone who is familiar with my blogs knows I avoid metropolitan areas while storm chasing.  I had no idea how much this philosophy would pay off on this day.

This chase consisted of a series of well-timed moves. We know the trouble would start somewhere west or northwest of the Oklahoma City.  We went down to Chickasha, OK and hung out just west of town a bit. This is when we first noticed some storm towers trying to poke through the cap. A cap is a warm layer of air aloft which tends to limit or prevent vigorous thunderstorm growth. A cap can be broken by daytime heating or by air being forced up through it.  It was apparent these first attempts were collapsing. It was also apparent that in about an hour, the cap would break.  This stop is where the first videos, pictures and time lapses were taken.

We then headed west to Anadarko, OK to get better aligned with the building cumulus towers.  More checking, more adjustments.  We headed north toward Binger, OK.

As we got to Binger, the first storms became visible.  Instead of the tops getting squeezed off by the cap, we now had a full-fledged storm with a base staring back at us!

While moving north, we had a choice to make: left would put us through Binger and on to Bridgeport on Interstate 40 while right would take us more northeast. I decided, based on what I was seeing, to take the slightly more westerly route northward.

The very interesting stuff starting happening while sitting in a casino parking lot just south of I-40 near Bridgeport. There were three cells on radar, which went under a severe thunderstorm warning shortly after our arrival. The southern most cell started to take over.  I’m pretty sure we were looking at the beginning rotation of what would eventually become the El Reno tornado. (see phot0)

Going east on I-40 wasn’t really an option given the eventual ESE motion of the storms. We decided instead to backtrack south to Hinton, OK and then to “stair-step” southeast, staying south of the storm. This also had the advantage of keeping south of the Canadian River and therefore good exit option south.

We stopped to try and see what was obviously a strong tornado developing (radar rotation very tight) to our north near I-40 but we just couldn’t see it through the rain! We did see a television helicopter flying back and forth along the southern edge of this storm.

Eventually, we ended up over on highway 81 south of Union City.  I check radar storm motions carefully and decided we could drive north just a bit toward Union City.  The next stop we made allowed us to see the Union City tornado to our NNE.  Once again, poor contrast and lots of rain prevented a clear view of this dangerous storm.  I’m told this afternoon that Bryan could see the tornado with the footage he shot and I’m anxiously awaiting this view of the storm!

Now, we decided as a group that further pursuit of this tornado was simply not an option as it was heading for Oklahoma City.  About then, we noticed a new circulation developing to our northwest.  We focused on getting in a good position to see this storm should it develop more.

In part two, I’ll talk about the second circulation and about the mass exodus out of the Oklahoma City metro area.

Also, a video review is in the works along with more pictures for the slide show.

 

May 212013
 

The radar view once we settled in on the hill

The radar view once we settled in on the hill (white circle)

The Moore/Oklahoma city was the single most devastating storm I have tracked while storm chasing!  I sit here the next day thinking about the destruction and loss of life caused by the storm and I still get a bit weak.

I’m writing this blog from a storm chasing perspective.

When you set out to chase storms, lots of factors need to be considered.  The one I wrestled with yesterday was seeing the incredible signature on radar, knowing it was a low-to-the-ground tornado and realizing it was likely tearing apart the towns it was striking, how do you chase?  My answer was: you don’t!  Not in this situation.

If we had come up from the south or west, it would have been different.  The tornado developed over open areas with good visibility at the start.  Here’s one video (although still way too close for a tour group!):

When it comes to the safety of guests, I wasn’t willing to drive into a relatively unknown metropolitan area to chase this storm. I actually think we would have been successful at seeing this monster tornado had we decided to drive in. But with regular traffic, gawkers,  emergency vehicles, flying debris (it goes farther than most people realize, the day will come when a chaser is hurt or killed by this!) and the unknowns about the exact size of the storm, it was a conscious decision not to chase any closer.

We decided to wait for the storm to come to us.  We spent a lot of time searching for a safe spot with a good view. But as I found out last year, the area east of the Oklahoma City area is much like the Ozarks, lots of hills and a surprising number of trees.  It took us about a half hour.  We ended up on a hill which provided a great vantage point but in a surreal twist we were just on the southern edge of the path of the tornado which struck Shawnee the day before!

The idea was to watch the tornado pass safely to our north. Fortunately, the violent tornado lifted. We saw the storm, tracked the weaker circulation and watched in pass to our north.

During the entire time coming down from Missouri through Oklahoma, the focus was on the science of severe weather forecasting.  We talked about things such as dew point depressions, helicity, old outflow boundaries, CAPE (a measure of unstable air), the dry line, jet stream winds and rotation cuplets on radar.

My tours are about the science of forecasting severe thunderstorms, tracking their development, explaining what is happening and staying safe!  Seeing a tornado is a great experience, I strive to do it, but it has limits.

Here’s a bit of video leading to our hill top perch:

 

May 092013
 

Outflow Area in Oklahoma at 6:30 a.m.

Outflow Area in Oklahoma at 6:30 a.m.

Lots of unstable air, an outflow boundary, a cool front and enough upper level shear should provide a stage for severe storm development over portions of Oklahoma and Texas today.

The upper air data from this morning confirms the necessary ingredients for the set-up.   There will be several possible start-up areas for storms today.

I am always wary of early development (noon-3 p.m.) and today this is possible in connection with a outflow boundary now easing into southern Oklahoma. I’d watch areas between Oklahoma City and Ardmore, OK first.

I’ll also be ready to head west quickly today to catch some storms along the dry line in southwest Oklahoma southward into Texas.

Interaction with outflows and fronts will be important for tornado potential today.  Also, patches of higher instability and careful tracking of upper level features will be necessary (if known!)

The”Lock and Load” tour leaves between 9:30 and 10:00 a.m. this morning.  We’ll be back sometime Friday afternoon.

As always, contact me if you would like to go, it is always an adventure!

 

May 082013
 

CAPE Forecast From 18z NAM Model

CAPE Forecast From 18z NAM Model

I’d say I’m about 70% in for the “Lock and Load” tour for Thursday, April 9th.

A “Lock and Load” tour is your chance to ride along with me and see some severe storms in active.

Since I’m considering southern Oklahoma and northern Texas as the chase zone, an overnight stay is required. “Lock and Load” tours leave on the day of the chase, stay overnight and then come back to Springfield the next day.

In this case, we’d leave Springfield in the 9:30-10:00 a.m. hour Thursday and come back Friday afternoon.

O.K., why the uncertainty? Well, I think we’ll have plenty of unstable air to work with but there are a few things I’d like to have “final eyes” on before I definitely decide to chase.

I have suspected all along that the computer models are not forecasting enough upper level wind with this set-up. The afternoon runs of at least one model seem to be supporting this idea. With regard to these winds, I would need to see the “truth” tomorrow morning which means what are the actual upper air wind measurements over this area tomorrow morning?  These would be widely available sometime after 8 a.m.

Then, I’m real curious about what happens with traveling areas of showers and storms tonight, many of which will likely form on the dry line in western Oklahoma. Depending on how these track, the mesoscale (small scale) could either be enhanced or diminished in some areas especially with regard to the low level wind field needed for tornadoes.

One possible target area is the dry line over Texas, say between Abilene and Childress.

There is also a weak cool front slowly sagging south through Oklahoma but here again, its position and strength will be regulated somewhat by what happens to storm and rain areas overnight and early on Thursday.

Dew Point/Wind Late on Wednesday Afternoon

Dew Point/Wind Late on Wednesday Afternoon

If you would like to go on the tour tomorrow, Thursday, May 9th, get in touch with me either on social media or by e-mailing me at: ted@tedwkeller.com

I can apply discounts the more guests I get to talk amongst yourselves!

 

Apr 142013
 

Twin Tornadoes North of Cherokee OK

[Note: this was from a chase about year ago , part of a large outbreak of tornadoes that occurred on this day]

It was the third day of an extended storm chase into the Great Plains and I have several good storms to show for it including an awesome twin tornado shot near Cherokee, Oklahoma during the last 20 minutes of the chase on Saturday, April 14th, 2012.

First off, there was an incredible number of violent tornadoes in Nebraska, Kansas, Iowa and Oklahoma on Saturday.  Thoughts and prayers go out to all affected.

Chasing is thrilling to be sure but I also learn more about tornadoes and supercells every time I head out.  The twin tornadoes pictured are an excellent example of how much different each tornadic storm can be.

The chase started in Kansas. We hung in east Kansas for a while on a hunch that something my fire there but abandoned this idea and started heading west in southern Kansas.  Several supercells were forming southward into Oklahoma and the plan was to catch one and then drop south to the next one, which largely worked out for us.

First Stop

The first encounter was south of Pratt, Kansas just southwest of the town of Sawyer, KS.  Radar indicated rotation with this storm and visuals confirmed the existence of a well-defined wall cloud.  The wall cloud passed just north of our position south of Sawyer.  It passed north of the town as well. We chased it north of town as it was weakening.  It looked is if a new circulation center had formed on radar but this was hard to get a visual on.  There was a tornado report on highway 54 just east of Pratt which seems to confirm this idea.

We stopped for three more supercells before dark. One was near Medicine Lodge. Once again, a clear rotation that never tightened up into a tornado.  The second storm was south into Oklahoma, it passed just northwest of Burlington on Highway 11.  We watched this for a while in the 7 o’clock hour.  It became clear that a larger storm to the south was hindering the development of this cell.

It should be noted that we were deprived of radar data at this point. 2G Verizon was the best we had which delivers images slowly!  If I had know how much larger the southern-most storm was, we would have broken off of the Burlington storm sooner!

With only about 20 minutes of daylight left we checked out the last storm. It was on the way home anyway. When we busted out of the “anvil core” heading south on highway 11, another wall cloud was visible on our right.  A family was watching this storm and said “you missed it” They were referring to a tornado which had already formed and dissipated.  I advised these folks to keep following us south as we were too close to the direct path of the storm.

Second Stop, Two Circulations

In the video, you can see a second tornado formed as we were driving south. The right twister appeared white in the sunlight.  We stopped again at the Highway 11/64 intersection just north of the Cherokee Airport.  This is where one tornado passed in front of the other (see picture)  and then became one again as it passed just northwest of this intersection.  A close-up of the ground dust and debris is included in the video too.

Finally, we took up a position in the parking lot of the airport.  The video shows this as a classic looking black tornado with a diffuse back-light made of of rain and hail providing excellent contrast even after sunset.

For those wondering, the Cherokee storm went on to produce the EF-3 monster tornado in southeastern Wichita later in the evening.

Probable Tornado Path (courtesy Disaster Mapping)