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Understanding the Impact of Weather on Maritime Operations - Part 1

Updated: Mar 22, 2023

The short answer is there is nothing vainglorious about surviving a weather event that you did not need to be out in or could have avoided through prudent voyage planning, read the forecast. I’ve participated in over a hundred ‘search and rescues’ over my time, and only one had a positive outcome. Remember that you never hear from those who have not survived these storms.

How do you tell the Skipper of a deep-sea factory trawler down in the Southern Ocean? They are the one who is curled up in the corner of the wheelhouse, in the foetal position, thumb in mouth, rocking back and forth calling for “mummy”. Make no mistake, this is how it feels, and this is what you want to do, but unfortunately, you also know you cannot do that, so you nonchalantly carry on as if nothing untoward is happening, making mindless drivel conversation, and acting like it is just another day at the office because you know that excreta flows downhill very quickly and that if you show the slightest sign of panic then the chaos will ensue. About now that job in the office looks surprisingly good.

Coming fast (stuck) is a part of Trawling that no skipper likes, this is the Will Watch backing up in bad weather, she is a notoriously ‘wet’ vessel.
Coming fast (stuck) is a part of Trawling that no skipper likes, this is the Will Watch backing up in bad weather, she is a notoriously ‘wet’ vessel.

I have done over a hundred- and fifty, six-week trips down the Southern Ocean, most as a skipper. Seaman and fishermen, all over the world, compare the oceans they are in, to the Southern Ocean, but there is nothing to compare the Southern Ocean to. Anything you have heard; I can guarantee you it's a hundred times worse. There is nowhere to run to, nowhere to hide, and the weather down there is the worst this earth can throw at you. Summer or winter makes little difference down that way, you can get

well and truly hammered any time of the year.

HMNZS Otago, Southern Ocean. On my vessel, I was too scared to take photos!

NIWA put waves buoys down the Southern Ocean. We were reporting waves more than can theoretically exist

let us get a couple of definitions cleared up before we go anywhere...

“It’s a bloody forecast for a start!” The people in the weather office will tell you that they can be up to 50% out in their forecast either way. That’s' right, 50% out! Remember that. They run a computer simulation, which is getting better all the time, though it can still be wrong, especially around NZ, where there are so many vagrancies due to geographical terrain and currents. Yes, you may know your area better than the weather office, and your own forecasts may be better or so it seems to you, but that is local knowledge, and I can guarantee you that if I were to collect your predictions over a period, your predictions would be a lot worse than the official forecast. When a forecast is issued, there is a range of predictions that the program spits out, the met service always takes the worst to be on the safe side, but remember it could be 50 % worse, so for example, a 20-knot prediction could be 10 knots over an area, or it could be up to 30 knots plus over the same area. This is what I want you to think about, that 35-knot gale you are out in could gust to 50-plus knots in places for a time.

SeaLogs has a little icon that gives you the up-to-date forecast for the area you are in, use it, the forecasting is so good these days that there is no excuse for not knowing what is coming.

SeaLogs uses the official met service (MetService, Te Ratonga Tirorangi).

A weather observation and information has been captured automatically
Example of the automated weather section in SeaLogs

I know there are dozens of other forecasting apps, I have got them on my phone as well, and I know that some of them seem to be a lot more accurate, especially around the North of NZ, but at the end of the day know this, they all use the same weather program.

These apps just take the more optimistic forecast or update on a more regular base, often in real-time. In that respect, it would seem better, right until you are trying to explain to the authorities why you ignored the official forecast and have now placed yourself, your crew, and your passengers in a position of extreme danger. So, use other services, but also use your own common sense, if there is a humongous black cloud bank heading your way, you are going to get a kicking!

So, what is safe weather to go out in? Every vessel is different, and the experience of each skipper varies but let us divide this into two sections. The first is recreational vessels. Before you go anywhere try to remember why you like mucking around in boats in the first place. My ideal idea of boating is flat calm, balmy summer days, anchored up in some picturesque anchorage sipping rum and coke with an ice-cold beer chaser, not battling a fifty knot, 5-meter seas in driving, freezing rain. Been there, and done that and I really cannot think of anything worse. It may seem exhilarating at the time, but if that is your wife and kids with you or your friends who are a pastil white colour, where they are frozen in place, what you have done is firmly put those people off the sea for the rest of their lives. Back it off a bit, if you want this egotistical life, the factory trawlers are always on the lookout for crew and a few beatings down south, fearing for your very life, seems to be an amazing cure for being an idiot. (The money is quite good though!)

When I see photos like this, all I can think is “what are you doing”? Go home.

We are making Hobbs Bay marina; it involves towing a barge full of rocks from the Tamaki estuary to Whangaparoa. The barge has a digger onboard to spread the load and unload the barge and there is a dedicated guy assigned to drive that digger. He is a hell of a nice guy, competent and good at his job, but he has a dark obsession.

His sister had been on a yacht that had gone down on a return voyage from Fiji to NZ, they were never heard of after leaving Fiji. It was presumed they had been hit by a sub-tropical low to the NE of NZ and overwhelmed. This guy would spend every moment of his time off searching bays and inlets in Northland for his sister, two years after the yacht had gone down. Think about that if you may for a moment, your actions can have a profound effect on the lives of others in an unintentional manner long after you are gone. I often relate to people; I am the only skipper I know of who fished the Southern Ocean for such an extended period and who has never killed or seriously hurt anyone, which up here in the pleasant Bay of Islands does not mean a whole lot, but if you can curtail your ego for just a little bit and pull back from the abyss then you will have earned your position as skipper but most of all, my respect.

There is another point I would like to make to both recreational and commercial skippers. I know the fish come on the bite before an intense storm, and that the temptation is to stay until the last minute, but it is just a fish for God's sake. Leave early and get home before the weather hits, mostly it will have been forecast and most times that changes, especially up north, the weather will come through with the change of tide, but here is when you are in the most danger. You will be tempted to push the limits of your vessel, most times you get away with it, but I have not survived this long by taking unnecessary risks, I have had to work absolutely extreme weather but I have always done it in a responsible, calculated, manner because at the end of the day you are gambling with other people's lives, even if it is just those that may have to look for you.

As for you commercial guys, work within the limits of the vessel and yourself. Build up to working in extreme weather, there is a simple word to say to the boss, NO! If it cost you that promotion or even your job, so what? I sailed with a multitude of incompetent skippers, who, if blessed with any special talent is the ability to spin a load of bullshit to the office while dropping you in the proverbial. I hate egotistical skippers, and incompetent skippers but most of all I hate brave skippers. That means anyone I consider braver than me and I am the eternal, perpetual, coward, I have the grey hairs, nervous ticks, nicotine, and coffee habit along with a healthy dose of PTSD and want nothing to do with egotistical, testosterone-driven maniacs that our industry seems to attract in droves.

The days when companies prided themselves on never missing a sailing due to weather are long gone. Operating conditions are clearly stated in your operations manual. If you exceed those self-imposed limits, because that is what they are, then it is not if, but when something happens, which will leave you spending a long time filling in reports and then explaining your actions to the authorities.

It is a truly miserable day in Auckland, a gusty South-easterly blowing a full gale with driving rain. I am driving the old Kestrel. As the day has gone on the weather has gotten worse so the bar staff have dropped the covers on the lower deck. I am on the last run for my shift and the weather has just gotten worse. We should have cancelled for a couple of runs but we have a reputation that we never cancel. On my last run across the Harbour and we literally sailed across the harbour, which means we approach Devenport doing somewhere in excess of 20 knots, or at least that is what it felt like. All I could think, even at the time, this is bloody stupid! I see now that the ferries quite often cancel runs due to weather, even though they have much more manoeuvrable and safer vessels, it would seem that this current load of skippers have not only grown up but are a lot more sensible and responsible than we ever were and for this, they have my utmost respect.

Lastly, when you are in extreme weather there are a few pointers I hope I can pass on.

First, slow down. Speed will kill you or else results in damage to your vessel. It may seem egotistical wholesome fun to pound through some sea but if you must slip, drydock, or spend thousands of dollars fixing the vessel you will not make any friends. If it takes a few hours more, so what? Secondly, try to take the seas on the shoulder of the vessel. It may be more uncomfortable but taking big green seas over the bow is a sure way to cause weather damage. A friend of mine was pounding into some reasonable seas east of the Chatham Islands. One of the bridge windows blew in and the sea filled the wheelhouse to the roof. The doors leading down below were shut at the time, so he was pinned to the wheelhouse roof for several anxious moments until the water drained. It completely ruined all the electronics in the wheelhouse, putting the vessel out of action for months, it took my friend almost two years before he would even walk on a vessel again and he is a big hairy arsed fisherman.

On the big factory trawlers, this was one of our main worries, taking a large amount of water directly over the bow. The wheelhouse is made of aluminium and when you have 3,500 tonnes of a vessel coming to a grinding halt, something is going to give, so slow down and take the sea on the shoulder.

Finally, stop pushing the weather. Do you care that I have experienced the very worst that this earth can throw at you? Not a chance, I was doing a job and if I had a choice of doing it in tropical balmy conditions then I would have been there in a flash. Nowadays, anything over 10 knots of variable flat calm sends a feeling of dread within me, it is not that I cannot handle extreme weather, I just do not want to. I am getting older or maybe even growing up, but at least I have gotten the chance to get old, too many of my mates and friends never got this far, and most of them were far braver and more competent than me, so back it off a bit.

This is my idea of a gruelling day at the office!

Part 1, check out Part 2 here

- Captain M Prendeville



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