Sailing in lightening - should I expect wind over and above the forecast?

[MagicalArmchair]

So, tomorrow is the only day I can bring my beloved Triola back from the Orwell to Chatham marina (the day job and crew availability are always the two jokers). Typically, the wind is on the nose, we're going to be leaving at 4am and its going to rain - fine, and fair enough. However, now the delights of the last 'proper' sail of the season of lightening too! The wind in the forecast looks pretty static and quite light, should I expect local squalls with this too? My crew is very inexperienced and I don't really want to put them off for life

What would you do? Tough it out, get drippy to get your boat back home? Or bail out for fear of the crackles, any associated squalls and making the crew a miserable, drowned rat?

 

[PuffTheMagicDragon]

Not knowing your boat, nor the locality, I can only wonder how realistic is covering 56NM in 12 hours especially since you anticipate that "the wind is on the nose".

(Not intended as being critical; just curious).

 

[AntarcticPilot]

You should certainly expect squalls associated with thunderstorms. These might be very violent, up to and including tornadoes (waterspouts over the sea), with rapid onset.

Do you really want to be at sea in a thunderstorm with your mast the highest point for miles around? Although theoretically you should be safe if the rigging is earthed to seawater, I'm not sure I'd rely on it when planning - being caught out there is one thing, deliberately going out is another.

 

[cliveshelton]

I did that trip in similar conditions on Sunday. We motored pretty much all the way. It took us about 9 hours and the last few were in squalls in the Medway (gusting 30). Since you will be motoring too, your inexperienced crew will be less hassled with sailing but it might be rocky and rolly of course. With that forecast I would make the trip in my AWB SO36i. Take ginger things with you to feed them if they feel ill. Good luck.

 

[Cantata]

Certainly you can expect squalls under thunder clouds.
However they've mentioned lightning in the forecasts around here several times recently and I have yet to see any.
The wind forecast you showed doesn't look particularly on the nose? Just not much of it.

 

[John 32i]

Think we saw you somewhere in the Orwell or Stour over the weekend?

It certainly changed quickly on Saturday; one minute we are anchored off Felixstowe beach, sitting in the sun having lunch...and then half hour later.. 25 knt wind, thunder, lightning and rain so hard that we couldn't actually see where we were heading!!

We did delivery trip from Chatham to SYH in 2015...motored most of the way as what wind there was was on the nose, took about 9 hours..but at least no storms!!

 

[MagicalArmchair]

Not knowing your boat, nor the locality, I can only wonder how realistic is covering 56NM in 12 hours especially since you anticipate that "the wind is on the nose".

(Not intended as being critical; just curious).

Thanks for the input all. She is an Albin Ballad, so she is a hardy and fast sea boat... who is very weedy. Last time we did that trip, we did it in far less time than my passage plan, circa 9 hours (I tend to predict on the cautious side as much for crew moral as anything) as we got the tides right (and she wasn't so weedy!). That last slog up the Medway will be a bit of a pig against the ebb this time though. As for wind, indeed, it looks very light!

Rain warning - typical:

Wind guru, using the WRF model at Mersea island reckons basically no wind.

And quite right! Its showing more from the North now, yesterday it was more SW

And finally, the met have downplayed the storm elements - no Thunder forecast anywhere. Looks like a damp, utilitarian, joyless chug to me with the occasional squally drama.

 

[MagicalArmchair]

No wind... at least six hours of solid heavy rain as per the weather warning... lightening forecast again in the area. Doesn't sound much like fun.

Discretion being the better part of valour, we are going to bug out of tomorrow. Added to that, this is likely my last proper sail of the season (lots of creek crawling after this mind you), and I don't want to waste it on a wet and grim chug.

Oh well, we'll try again in a coupla weeks and use the excuse to visit the boat at the weekend and spend some time in lovely Suffolk.

 

[johnalison]

I'm no meteorologist but I believe that there are particular conditions when thunderstorms give rise to squally winds. We once rode out 60kn winds anchored off Osea island when the forecast was late coming but accurate. Generally, the ones I've experienced at sea have only given moderate winds up to 30kn and often far less, and always too briefly to create anything of a sea. If it is necessary to do the trip, I would go for it myself.

 

[MagicalArmchair]

I'm no meteorologist but I believe that there are particular conditions when thunderstorms give rise to squally winds. We once rode out 60kn winds anchored off Osea island when the forecast was late coming but accurate. Generally, the ones I've experienced at sea have only given moderate winds up to 30kn and often far less, and always too briefly to create anything of a sea. If it is necessary to do the trip, I would go for it myself.

I have one more chance to have a good sail later in the month back. Its more having little or no wind that will put me off, and all that rain that might have put my crew off (crew I've been trying to convince sailing is more than burning money whilst being wet, miserable and cold... wait, who am I kidding )

 

[franksingleton]

A few comments.

First, I am extremely wary when thunderstorms are forecast. A lightning strike can cost you a lot of cash and may kill. So, if the forecaster mentions thunder or thundery showers, treat it seriously. Always know what the GMDSS forecasts say. Don’t trust any automated forecast.

CAPE is an index of potential lightning risk. In other words, you may have a high CAPE index but no showers. If conditions are right for showers then a high CAPE value should be taken as a serious risk.

There are two (at least) websites that show current lightning. http://en.blitzortung.org/live_lightning_maps.php?map=10 and LightningMaps.org. These show what is happening now. They can help you to see if there is any activity near or approaching you. Used with, say, http://www.meteociel.fr/observations-meteo/radar2.php?region=uk&mode=1 These can be really useful.

Lastly, with heavy showers, squalls are often a possibility. Just the sheer weight of the falling rain can drag air down and spread out in any direction. Tornadoes over land or waterspouts over the sea can be a consequence.

I know of no guaranteed way of protecting against being hit by lightning. I do have a Lightningmadter “bottlebrush” riveted to the masthead and the mast connected to a sacrificial anode. I am pretty sure it saved us when isolated thunderstorms were forecast off the south of Sicily. One appeared out of the haze right over us. We could hear the air being ionised. Very frightening and an experience not to be repeat4d - I hope. Whether we would be protected in a similarsituation, I do not know.

See http://weather.mailasail.com/Franks-Weather/Cape.

 

[Spirit (of Glenans)]

Not knowing your boat, nor the locality, I can only wonder how realistic is covering 56NM in 12 hours especially since you anticipate that "the wind is on the nose".

(Not intended as being critical; just curious).

Yes, if the wind is on the nose you must allow 50% extra distance for the tacks; 56nm +50% = 94nm. Allowing 5kt boat speed that would equate to 19 hours sailing. I know its hypothetical at this point, but just sayin......