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View Full Version : On the Chasing of Storms - Advice, Risks and Links from a Storm Researcher



Xebadir
22-12-2011, 12:58pm
I have written this to address a post which concerned me about the chasing of storms, which for me really didn't target the crux of the issues and the risks associated with chasing storms. I have attempted to provide as much knowledge as I can without running into several dozen pages, and will add to it with some other material when I get around to it.

In my mind a critical aspect of storm chasing is preparation, and understanding. Too many people think that storm chasing is a reactionary pursuit, where you can suddenly go chase a storm after no preparation. The reality is that long drives, hours of waiting, the trials and tribulations of forecasting and the potential you will see nothing is also there....despite everything looking perfect! Sure, there are times when I may chase an unexpected storm, but most of the time I am aware well in advance of the risk, and prepare myself accordingly...my forecasting is pretty damn accurate, as is my ability to read the storm and it allows me to be successful quite often...this isn't the story for most chasers. Some talk of using radar for detecting thunderstorms, but to me it starts by considering model forecasts, and even just smelling it in the air on a storm day. Radar is a useful tool, but unless you know how to read it, and do so well it can get you in to trouble, and the features shown by australias limited radar aren't always what the storm is doing...the other day we had a tornado on the ground and the storm barely looked more than a shower.

I'd urge caution on this "radar chasing", and make sure you understand what you are dealing with before you go getting out there to watch storms. I'm a professional meteorologist, and have chased here and in the states extensively for the past 7 or so years (done more than a circumference of the planet in the past year while chasing, and I can honestly say I was probably one of the most frequently chasing people on the planet last year), and I don't claim to be infalliable in dealing with the associated hazards, but here is some things I would urge you to consider before contemplating chasing:

RISKS

This is a shot from a recent storm I chased near Nyngan/Parkes. The big one thats closer is about 5.5-6 cms, while the one at the back is over 7.5cms.

http://img94.imageshack.us/img94/112/hailnewsouthwales.jpg

This sort of sized stone is not unusual in the organised type of storm....storms which are relatively common north of the Great Divide and along the east coast.
If you drive unawares into this sort of storm, you are going to wreck your car. In Australia I know a number of guys who have lost windshields and got significant car damage from getting trapped on the wrong road, or driving into the wrong part of a storm. In the states...people who chase may go through three windshields in a single year! (Granted...10cm hail is pretty much an everyday occurence during their spring, with storms producing up to 8 inchers later in the season). The key to avoiding hail damage, and indeed being injured by hail (one of these hits you, anything above golf ball and you could break bones, larger hail has a reputation of killing people), is understanding the storm dynamics and physics, as it gives you a better conception of where is safest from hail, and where to position yourself (a word of warning here, even I come unstuck, as do the researchers in the states...sometimes storms don't follow the rules and sling 5 inch plus hail into places it shouldn't be...happened last season twice). So hail is a major threat to you and your car, should never be taken lightly, and I would strongly discourage you from chasing a storm on this basis if you don't understand when and where the storm might produce it.

The next problem to worry about doesn't even need a severe thunderstorm. Its lightning. Lightning is a fickle thing, and you are at risk any time you can hear thunder....storms can produce what we refer to as a "Bolt from the Blue" an unexpected flash of lightning from the upper parts of the storm, with killer potential as much as 20 kms away. The average strong thunderstorm can have flash rates in excess of 3 per second...thats 3 strikes every second...and you might be next. Any thunderstorm can produce it, and its one of the worst killers in Australia and indeed worldwide...more people are killed by lightning that tornadoes per annum! If you see the flash and hear thunder within 5 seconds...you are in deep trouble as this is the most dangerous place to be...you could be hit any second...especially if you are the tallest local object in a bit of flat country...or on top of a hill. The safest place to be in this situation is inside a structure, away from windows, or if you are not able, a car is also pretty good thanks to the rubber of the tires. If you can't make that, drop yourself low as possible to minimise the potential. Tripods in this situation are a bad idea, again another thing to hit for the lightning. If you feel static hit the ground....immediately. Its a weird feeling which will scare the hell out of you, but better that than dead. Shooting lightning at any time is a risk, try and minimise your exposure, you have to remember something posted on another part of this site: Is that picture really worth your life? True be told, most lightning shots are rather dull, while every bolt is different...so its not really worth the risk if you aren't aware of the danger.

http://img846.imageshack.us/img846/6431/alittleclose.jpg

This is shot at about 50m from a moving vehicle using my full frame wide...there is no way I would be outside in that storm...we had 10 hit at that range in only a few minutes...we were driving across Missouri at the time. I have seen lightning hit a powerline right above a storm chasers head (I have a video somewhere)....scared the crap out of him....the guy has been terrified since, and refuses to come out in lightning.

The next risk, and one of the more common ones is flash flooding. If you are in a vehicle, NEVER attempt to cross a flooded area unless you are sure of the depth, and its only a few inches....the strength is enough to sweep cars off bridges, and the road can be deceptive. A friend of mine has a classic image of before and after...the flooded version looks like flat road, the actual road turns out to be metres in its drop. If your engine bay floods you can forget using your car...it will break down and probably be useless such you will need a new one. Severe thunderstorms can drop rainfall rates in excess of 100 mm/hr.....to give you an idea, thats 10cms x Area ....on just one area 10mx10m thats 10,000 Litres, or a small swimming pool. Now given the storm is going to be over an area 5-10kms then you can understand the danger. Once that water falls it will start to flow, and that raises the danger. It also makes the roads incredibly slick and can cause Aquaplaning....something that is very difficult to deal with. I drive in these conditions alot, and its still risky, so remember to take it easier on the roads...you can also get almost like black ice when lots of hail is falling....6 inches deep can accumulate and make driving a real challenge. Dirt roads of course can be become impassible in bad conditions too.

Finally we get to what I call the debris risk, or wind damage issues. Gum trees are notorious for falling over, snapping or losing branches in strong winds, and thunderstorms can produce up to 200 km/hr just from a normal wind gust. When that happens in sheeting rain, you can get a whiteout condition which makes it Impossible to drive. Hitting a branch at speed can do real damage to your car, as can having a tree fall on you, or drop a branch on you...its pretty common with thunderstorms for branches to make roads impossible, doubly bad if you have flash flooding forcing you to flee. The other thing that can be deadly is debris from these gusts...things can splinter, debris can fly, parts of houses can come off (including rooves). Tornadoes are also seen in Australia...as many as 100 in a year at times...these at strength (which does happen) can throw cars, branches and trees into the air, not to mention create deadly debris, in the following you will see full grown Macadamia trees hundreds of metres into the air. Heres an example from a friend of mine:
http://www.youtube.com/watch?v=1SD_OzpQaU8
You definitely don't want to be that close, and if you don't understand what the thunderstorm is doing you can get caught out unawares, and before you know it you are a statistic with a sad family.

So I guess thats the end of my negative nelly diatribe. My greatest fear is that someone will die chasing without knowing what they are doing....there have been many close calls already, and several car accidents which have resulted in fatalities. I don't want to see the same risk taking actions in Australia that are growing in the states....you really have to respect the thunderstorm, or you will get hurt.

Chasing Resources

I would strongly urge you to learn something of meteorology before even thinking about try to chase storms, or photograph them. Get on a forum like www.weatherzone.com.au/forum
and learn from people like myself who have the experience before attempting it. Its how I learnt more about chasing (granted I learnt fast because I have a knack for meteorology, I saw my first major hailstorm at 6 and have been fascinated ever since and now am more qualified than most severe storms forecasters in Australia), and knowledge is the only thing that will help keep you safe. While I am not a particular fan of some of this guys theories on meteorology he has produced a good introductory resource to at least get your feet wet with understanding, see:

http://www.downunderchase.com/storminfo/stormguide/index.html

One of things Anthony talks about is reading the atmosphere, I completely agree that an understanding and ability to interpret what you see is critical:
http://reg.bom.gov.au/storm_spotters/handbook/foreword.shtml
The above is a good resource allowing you to at least get a basic understanding of what can occur in a storm...the bureau is very anti chasing for fear of lack of knowledge getting someone killed. The best thing to do is find an experienced chaser to learn from, their knowledge could be vital one day, and will minimise risks while learning, plus you get someone to watch the storm with and share the excitement!

Storm photography is a whole other topic, and something I will write later as this is too long already, though it may take some time as its quite expansive and different to normal landscape photography, and my own approach differs substantially from most.

Its not that I am saying you can't do it, but safe chasing is one of my highest priorities and should be yours too...storm chasers shouldn't be thrill seeking and taking un-necessary risks, to do so places a burden on emergency services which may be needed by people who have no choice in the matter. If you are interested to learn more, want to hear more about storm chasing, or need advice I am happy to recieve and reply to PMs, one of my great joys is sharing the knowledge of the atmosphere.

I will add more to this thread as I get around to it, but feel free to prod me if you want to know more.

Regards
John

Lazyshooter
22-12-2011, 9:38pm
Excellent advice and a great post. I can't agree more with what you have said.

Dink
23-12-2011, 1:19pm
Thanks John.

I have just read your post and found it very informative, and thanks for taking the time for post it..

I think that my post is a little under informed but it was only a guide of what I do ATM. and was never meant to give some one a false Idea of how to be safe in storms.
I have been researching a bit on forecasts and models with in the Rural Fire brigades and how weather works and affects how they change the behavior of fires but have know where the amount of knowledge that you do.


I Thank you for pointing others in a area in which you have more experience than I.
I hope I did not give the wrong impression of this dangerous activity.

Cheers Dink

P.s i would like to add that I will post my questions and quires in the forum so others can learn form them...