Squalls, Thunderstorms,and … Gales ???

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And on the french Sail The World server a VERY GOOD discussion about lightnings, and how to handle or prevent the damage they will generate.

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Getting the boat ready for the ARC+ and for the Trans-Gascogne race that will be last week of july, and first week of August (Hanami 2 will be an accompaning boat), it was intersting to refresh the ‘how to handle document’ relative to squalls and thunderstorms (TS) The following is an ordered list of things I believe worth to keep in mind ; they have been collected whilst reading various web sites, then mixed with my own experience. The intention is definitly not to rewrite Peter Bruce's 'Heavy Weather Sailing' that is the reference book, but as I have my notes written down why not share them?

The basics : WIND, RAIN, LIGHTNINGS

During squalls ( frequent during transatlantic crossings) and TS (as found in the Biscay bay) the winds can go from 5 to 40 kts in a hand-full of seconds. Squalls generaly don’t have lightnings but, when meeting TS lightings may well be one of the biggest concerns after the strong gusts of wind. Nevertheless, in the ITZ (inter tropical zone), squalls and/with thunderstorms are frequent and making a clear-cut difference may be difficult or just theoretical.

For both, a very important concern will be the possibility of being knockdowned, with spreaders touching the wave’s crest or, worse, the boom touching . It is one of the reason why I believe that, if sails are down, it might be worth keeping the boom in the center or, if sailing/motoring windward, it should be oriented down the wind direction and secured.
We did this during a Messina strait crossing with heavy rain and 40+ kts of wind and it helped a lot.

An other concern, when sailaing downwind with a boom brake/preventer set and not enough reefing, would be the battens being caught in the shrouds if a gybe (jibe?), blocked by the boom brake/preventer, did happen. We experienced it twice with a preventer, with the engine not running, on the way back from the Carribeans to Horta, and bringing the boat back ‘into the line’ proved tricky . To boot, this was by night and with a couple of cargos near by that we could track on the radar and AIS. Additionaly the sail, at the batten level, did suffer a lot from ‘acute’ chaffe. During coastal cruising the danger increases significantly because of other boats, lack of free water to run, poor visibility because of heavy rain, darkness and poor visibility among other things …. At this level, dropping the anchor, if possible, may be considered. Even if it won't hold firmly it will slow down the process and may be enable rescue before it is too late

Picture from the Ouest France web-site.

First things to do with the sails : REDUCE !

Roll the Genoa first. If Spinaker and other Code 0 or Genaker are still up they have to be dropped beforethey tear apart. Reef the main to first or, better, second reef and drop the traveller OR drop the main and secure it with ties. If the main is kept up, even with 2 reefs, releasing the wang is a safe option. If there is/was a boom brake set it twill have to be reset, still securing the boom in a safe position. The good time to reef, is when the wind becomes cold or the temperature drops. The objective is to roll the genoa and stay under reefed/rolled headsail only If it is necessary to go to the mast clip on it and do it short. In Squalls it might be worth to hive to, just to let it pass and, if its manageable ,to take advantage of it to shower as reported in all transatlantic crossings.

Here is a link to a previous posting, in french :-(, dealing with the proper amount of canvas to wear according to the wind speed.

How to do it twill depend on the wind angle.

When sailing windward, turning up into the wind will let let then main luff. Letting the mainsheet out isn’t mandatory. Facing the wind, the boat will slow down and it is time to roll in a bit/lot of Genoa (though I prefer furling downwind).
It will be a good time to reef the main to 2nd reef. There doesn’t seem to be something as ’too much reefing ‘ .
Then it twill be time to come back onto course and let the main traveller out as well as the main sheet to keep the sail luffing.
If sailing windward, with the main down and secured, bringing the boom in the wind axis (using traveller and sheet) to reduce the wind effect seems a good idea.

When sailing downwind, stay downwind, but not ‘full downwind’ : it is too dangerous. Keeeping the wind on a 30 degrees angle (a bit more than a broad reach) seems a good option. Ease the main sheet, still trying to avoid it touching the spreaders as it would complicate reefing, increase the risk of the battens being caught in the shrouds (or broken) and damaging the sail
Then the genoa should be rolled in as i twill be in the shadow of the main.
Remains to come back onto course and set the main as above until it luffs.

Rules of thumb. Squall => Reduce main to second reef. Big Storm coming in => DROP or reef to third reef. Keep a « hanckerchief » of Genoa to equilbrate the boat. In both cases do it soon Of course it is a 'minimalist' approach but it usually work if done soon.

The crew and the boat.

Foul weather jacket, everybody clipped to the lifeline and tether shortened.

Everybody non needed down below and secured.

Start engine in neutral ; having it ready if anything goes wrong, like an untended 'heave to' leaving the boat with the waves coming abeam, will make a big difference.

Get everything out of the way and off the cockpit, secure what's left.

Batten all the hatches and close, even partly, the companion way.

Shut down non necessary electronics but follow the squalls on the radar screen and try to escape it knowing that squalls change direction rapidly, hence look at the trend more than position.

GPS, Phone and iPad with a navigation SW in the oven in plastic box. In case all the electronic is destroyed by a ligthning hittingthe boat, those ones will remain, the oven acting like a Faraday cage.

If there is a dingy in tow bring it in or close.

At the helm.

Getting ready for fancy wind directions and speed is necessary as the wind will turn by the time the squall is crossed.

If the storm hits, run down-wind but not ‘head down-wind’, more like a broad reach to escape the storm as they usually last less than 30' and usually travel fast.

Be ready to take the helm but stay on autopilot or wind-vane when possible and hide in the companion way to avoid getting drenched and/or too cold .

If a diving mask or helmet available, then put it on if very heavy rain is anticipated. We didn’t have one when crossing the Messina straigth and we learnt from it.

In big and lasting storms be ready to use a sea anchor,a drogue or trailing lines.

If close to shallow water be ready to drop the anchor with lot of chain recognising it will rip and rarely hold strongly.Here is a link to a posting dealing with anchoring in heavy weather.

If close to Florida, stay OUT of the gulf-stream if close to it.

Notes.

Difference between Thunderstorm and Gales

The effects of a storm (temporary) and a gale (long lasting) at sea are quite different. 25 to 35 knots of wind blowing over several days across the North Atlantic may be a killer : the big seas will build up into something which can capesize and/or dismast a boat, or sink her if she pitchpoles whilst sailing down the waves.
A thunderstorm won’t have enough time to produce such sea state ; even if it can be thrilling sometimes, it is rarely very dangerous. Nevertheless, the Meltem, white-storms in the med or the Pampero can be really dangerous. There is a full litterature about it on the web.
In case of doubt the silver bullet in high winds is running off downwind may be bare pole and/or trailing lines or a drogue or a sea anchor.

Quotes from the web, which I liked a lot :

In my club racing is described as go-out > shout > break things > write cheques > drink > go-out......

1) start praying (works whether you are religious or not ;-),
2) try to sail away from the cloud,
3) back to 1),

And there are probably many other ...