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.