Storm avoidance - I FAILED but need help

[CaptBobR]

PW and Windy do not predict the path of thunderstorms and limited squalls. Radar will alert you to the storms coming but that doesn't do much more than an hour or so. But it does give you enough time to reef and prepare.
Prediction services cannot accurately forecast very local conditions more than a few hours our so on a long distance passage, they will not really do the job.
Preparing for a storm and coming up with a plan is a key knowledge element for long distance passages. Whether you feel more comfortable heaving to or sailing under a reefed sail, you need to understand you will face unpredicted weather events

[Timlich]

I have very strong views on this subject based on both coastal and ocean passage experience. A weather forecast is only ever a prediction. As sailors we shouldn’t expect the forecast to be 100% accurate. Sometimes they are and sometimes they’re not. It should only be a tool to help us plan our time ahead at sea and give us an approximation of what we might expect. If you set off to sea and expect to be able to avoid every adverse condition nature can throw at you then you’re going to be sorely disappointed. The best we can do is mitigate the risk by being as prepared as possible - know our boat, check our equipment, ensure everything is in good working order, reduce sail before darkness, have established wind strength parameters for when it’s time to reef (there’s an old saying that the right time to reef is the first moment you consider it) etc, etc (the list is long). If you’re well prepared then you can have faith in your boat and in yourself. Most of all, as sailors we must be prepared for the worst and when the worst hits, we must have strategies in place that we have at the very least considered but at best we have rehearsed. Storms and other adverse weather challenges will always be a part of sailing. And don’t be afraid to ‘be afraid’ - fear at sea is healthy but it’s how we respond to our fears that determines the outcome for us.

[Amapola]

During the summer, afternoon storms are the norm.

[sck5]

Passageweather is quite useful and as accurate as any of them are

https://www.passageweather.com/

[sck5]

"Log Barometer readings every hour"

Sure, a good idea but does anyone actually do that? At the end of each watch is all I ever managed to actually record.

[RH112]

Originally Posted by MicHughV

Back in the day, when I (and many others) first started to sail the US east coast, there was very little in the line of marine weather forecasting. There was certainly no internet, no weather maps or apps, etc....pretty much your only source for marine weather, was the NOAA forecasts available on your vhf. If things looked relatively good outside, you took off.
99.9% of the time, I'd have a good trip. If the wind direction or strength changed, I altered course to suit. Occasionally, I had to heave too outside an inlet to avoid a night entry.

These days, ...

To me, the weather is the weather is the weather. It is never constant. It can change by the hour, the day, etc. Even the best forecasts are rarely accurate beyond a few hours.
...
Don't let yourself get bogged down by information overload. Seems like most people these days, just want to get from A to B in the shortest time, forgetting, that sometimes you have to go to C to get to B. That's sailing. Straight line trips are for powerboats with big engines.

You are SO right and perfectly match my observations in the last couple of years. Thanks for posting this!

[patmvcr]

I don't have the patience to go through everyone's replies, but having originally majored in atmospheric physics in university and still being a weather nut this is my advice.

the problem with standard forecasts is they don't give you the relative confidence in the various models ...and therefore forecasts.

The US national weather service provides the public with an EXCELLENT product. It's called the Area Forecast Discussion (AFD). These are discussions issued every 6 hours by the person in charge in the various weather offices in the US. I wish we had such a product here in Canada.. but I refer to the Seattle office AFD if I really want to know what is likely to happen with the weather.

The AFD is filled with jargon, but with the magic of the internet you can learn what these terms mean. They are usually quite in depth (depends on the forecaster though) and I find it to the best way to judge what the likely weather is going to be. They discuss convection as well (pop up storms).

I'm a PNW sailor but with my knowledge of weather I can tell you that your course took you near the margin of the Gulf Stream which can produce some very bizarre convective weather. Nevertheless, the AFD will give you an indication what the CAPE (likelihood of convection) is etc.

This is the link to the NWS AFD page:

https://forecast.weather.gov/product...WS&product=AFD

Here is a link to Wilmington NC's AFD:

https://forecast.weather.gov/product...D&issuedby=ILM

[Lagniappe]

I use Marine Weather Center for what I believe are the best weather forecasts available. Chris Parker and his staff have made provided me with accurate offshore forecasts for 7 years of full time live aboard cruising both coastal US and throughout the Caribbean. We use Windy and Predict Wind for planning and then validate with Marine Weather Center. You can contact them through MWX.COM

[Borja]

Originally Posted by PLANET EXPRESS

+1 what Chris Mac said cape index for storm potential.

+1 for developing some knowledge on CAPE index or other atmospheric stability indicators and how it interacts with synoptic conditions (besides shipboard observations like radar, swells changing directions, clouds, etc)- I just mentioned this on the threat about the recent Corsica squall.

Windy and so on can help with this: for example on Windy, not only do you have a CAPE layer avaialble' you can also check the deviation metric - a high number means high uncertainty on the forecast. Also simulated base reflectivity, a metric that goes by different names. I always keep tabs on those things.

This slideshow was posted on the other thread but is relevant here too:

https://wild-silk.org/storm-in-formentera/

Originally Posted by recurveman

Never felt unsafe for the conditions but I was worried conditions were going to change for the worse.

Understandable, but there's an English (or American?) saying that goes "Long foretold, long to last; short notice, soon to pass". And Portuguese fishermen have another relevant one which is "Se tens vento e logo água, deixa andar que não faz mágoa" - if you're hit by wind and rain right away, then carry on because it won't hurt you.

There's wisdom in these old sayings - these quick-forming convective storms don't last for long; and when you're hit by rain earlier on, it generally means there's no worse yet to come. It'll be uncomfortable, but as others have explained well, fairly harmless in deep waters.

[JPA Cate]

Yes, the over quickly bit is really true. Squalls are of briefer duration than frontal passages. We have actually left secure anchorage, and gone out into the path of a big afternoon thunderstorm, mostly because it was the right time to catch the flood at our destination, an overnight sail away, and the synoptic flow was favorable, too. We don't make a habit of it, but we would do it again in the same conditions. However, we do have years of experience in the open ocean to draw upon.

About the Australian weather forecasts, what they actually say is a little more complicated than what Boatman61 posted. They say, "...wind strengths may be up to 40% stronger than the averages given here*, and wave heights up to twice the height."

*In Oz, the averages are taken for 10 minutes, and that period may contain some strong puffs in blustery weather. Averages reflect the "tails" of the mean. And, the wind quickly creates chop on top of the swell. I tend to use 50% stronger (because the arithmetic's easier for me to do in my head, plus it is the conservative estimate direction). Such thinking is useful especially for thinking about "active" frontal passages.

To be really clear here, I'd like to say that in my opinion, there was no failure on the part of the skipper. All landings you walk away from are not "failures".

The events related indicated to me that the skipper needs more time with the boat in stronger conditions, and that someone with more experience with his type of boat and similar weather could help him learn more quickly to improve his skippering skills.

Ann

[skipgundlach]

Originally Posted by Lagniappe

I use Marine Weather Center for what I believe are the best weather forecasts available. Chris Parker and his staff have made provided me with accurate offshore forecasts for 7 years of full time live aboard cruising both coastal US and throughout the Caribbean. We use Windy and Predict Wind for planning and then validate with Marine Weather Center. You can contact them through MWX.COM

I concurred in an earlier post about my 14 year experience.

N.B., however, the website is mwxc.com as in marine weather center dot com.

His direct email is chris@mwxc.com...

[carstenb]

Originally Posted by sck5

"Log Barometer readings every hour"

Sure, a good idea but does anyone actually do that? At the end of each watch is all I ever managed to actually record.

We record the our log every 2 hours, including the barometer.

ON weather forecast - we just (yesterday) sailed SF to Montery. Windy, Predict Wind and Noaa all said, winds 12-15, gusting 22-24 knots.

Swells 1,5-2 meters, period >8 secs

What we got was winds constant at 25+, gusting 37 knots, swells 2-3 meters, period 6-7 secs.

Entertaining ride, albeit we were tired when we got in - average close to 8 knots speed.

WE had the same issue when we sailed from Neah Bay to SF last week. Wind and swells were far above expectations.

As we learned when we studied meteorology - forecasts are only probabilities and actual conditions will vary - Forecasts show the average winds and swells

AT any rate - no matter what the forecast - you should be ready for most anything when you go out

[Rockinar]

Originally Posted by MicHughV

As above, I've done many an offshore trip and have often been nailed by these "thunderstorms". which typically arrive late in the afternoon or early evening, sometimes even late evening.
My experience is that they are usually short lived...20-30 minutes, during which time wind speeds and wave height can jump up quickly.
I sometimes try to sail thru' them with shortened sails, but most often, just take everything down and let it blow me whereever. I kinda like 'em, as it washes the boat down.

Typically, within an hour after, seas quieten down again, and often there is no wind at all.

At night, while you might not be able to see the rain clouds coming, you can usually see the lightning and smell the rain, at least I can, which can give you a 10 minute warning.

The first ever time I got nailed by one, I was a bit panicky, but these days, I take it in stride, and so will you.

You just bare pole it and go make a coffee? LOL Thats hardcore.