What 9,000 Miles Taught Me !

[Stillraining]

For me reading threads like this is a love hate relationship...loving the knowledge learned and dreaming of adventure someday at sea...and hating the fact my wife may never become like a Nicolle...for better or worse right guys.....Its a darn good thing shes cute...

[Whoosh]

Mark, you've lost me a bit. Watching not just the development of the first low you describe but also the persistent W & SW winds that are left behind after it departs - very much the opposite of what the pilot charts suggest - does indeed look obnoxious. And then there's that second low that subsequently builds just NW of NZ, with its own distasteful consequences. But what I'm confused by is how this supports your routing choice, since you left a bit sooner than this (when these lows are more likely, right?) and your route went right across the affected area.

I'm obviously missing something; can you clarify (here or via PM)?

Jack

[MarkJ]

Originally Posted by Whoosh

Mark, you've lost me a bit. Watching not just the development of the first low you describe but also the persistent W & SW winds that are left behind after it departs - very much the opposite of what the pilot charts suggest - does indeed look obnoxious. And then there's that second low that subsequently builds just NW of NZ, with its own distasteful consequences. But what I'm confused by is how this supports your routing choice, since you left a bit sooner than this (when these lows are more likely, right?) and your route went right across the affected area.

I'm obviously missing something; can you clarify (here or via PM)?

Jack

Hi Jack

Mark, you've lost me a bit. Thats my navigational skills

See the 2 attachments below: one "Now" and the others the grib for 24 hours time.
The Black line was my route and the Red line was the route recommended.
I wanted the black route so I wouldnt have to punch into the southerlies along the coast. South Easterlies are strong but on the quarter. Out to sea it doesnt matter as one can bare off to the west towards the red line course.

persistent W & SW Where??

very much the opposite of what the pilot charts suggest: Local knowledge says southerlys and South Easterlies are the worst. Pilot charts have taken a beating in my estimation. The pacific showed no resemblance to the pilot charts. Further, I think, but don't know, but wind is given in TRUE not MAGNETIC putting it 15 degrees off. GMS = S is almost SE; SW is almost S


how this supports your routing choice, since you left a bit sooner than this (when these lows are more likely, right?) and your route went right across the affected area.

This is a late season Low. I waited for these lows to dip down south which they did by September 20th so I left Tonga. This one is like a throwback to a winter stom. Note the Pilot chart is quite different between September and October? I was hoping to have the first of the October weather when I got closer to the Australian coast.

This was the type of feature I was hoping to miss. I was lucky

I'm not saying my way was the best way, but it worked for me because after so long at sea since Panama, with old sails etc and some old running rigging, I didn't want to go into a 40 knot headwind. So my way would have kept most bad winds on the beam. (Except a South Wester, which I would have not liked at all, but I could have made more northerly and headed for the Red line course till it had blown out).


Does this make it more clear?

Mark

Attachments:
NOW............................................... .. 24 Hours time

[Talbot]

I set this problem up on my passage planner taking into account current and predicted weather - and ran a straight (rhumb) line course plus a dogleg course as close as I could get to your pictures for both September and October

The reports give me much more data than I am giving here, but it is interesting to compare the two months, and they would suggest that your choice was a marginally better one anyway!

Dont look at the waypoint positions too closely, I didnt spend much time on this!

[MarkJ]

Originally Posted by Talbot

I set this problem up on my passage planner

Thanks for that, very interesting.

I don't see how the dog leg can be 200 miles shorter than the rhumb line?! Thats just impossable.

The funniest thing is :

Average Wind Speed: 12.1 Knots

LOL I wish we had it somewhere around there And I guess anyone out there at the moment would be wishinig it too

Mark

[Talbot]

Originally Posted by MarkJ

I don't see how the dog leg can be 200 miles shorter than the rhumb line?! Thats just impossable.

??????????????????????????????

Straight rhumb line = 1560.2

Dog Leg , 1st leg = 1358
2nd Leg = 368.7
Total = 1726.7

[at_my_beach]

We have got a nasty southerly at the moment. Just at the tail end of it now, but still 20+ knots was up to 45.

If you want a visual go to www.coastalwatch.com.au and look at the live surf cams. The NSW cams are listed north to south with Byron Bay North and Bondi at sydney.

Cheers

[lolanreg@smartc]

Welcome home! Sydney Harbour is always a great place to sail home to. If you come up North to Yeppoon, and the Keppel Islands give us a call.

[Whoosh]

Mark, thanks again for expanding further on your run. All good stuff. And that low you invited us to look at in the gribs a day or two ago would indeed make such a passage memorable. (Watching the week's winds unfold in the gribs produced the SW and W'ly winds I mentioned).

And Talbot, we just finished a Greece - Florida USA run after I'd started using the VPP software used in those examples and it sure did leave me scratching my head. Much of the Med weather is front-generated so averages aren't very predictive but we expected the pilot charts would become more representative of the real stuff once we headed for the Canaries. For me - and let's assume VPP does in fact accurately portray the pilot data - the interesting lesson was how much latitude exists between the 'average' wind strengths and what one sees day to day. As one example, just during our Canaries - Trinidad run (~18 days) in late Nov/early Dec - when if anything the pilots suggested there'd be too little wind, 3 boats sunk due to structural failures. Good Aussie friends on PENYLLAN almost lost their rig. We could all laugh afterwards, while counting up all the Euros of spare diesel fuel we'd bought for the motorboat ride.

Jack

[Talbot]

As in any statistics, they are really meaningless, unless you understand the assumptions, and also what the error bars are, and spread from which they achieved the mean. VPP and the pilot charts provide none of this additional data , thus info derived from it, especially for wind, needs to be treated as a guideline only, and thus I would suggest that the purchase of all that extra fuel was a sensible precaution based on those guidelines.

This ranks alongside the purchase of series drogue or parachute in case the winds experienced are at the upper end of that spread.

[stephenbriggs]

How long did your trip take and were did you leave from.

[msponer]

Originally Posted by MarkJ

6) Don't listen to other cruisers! Make your own plan and decisions

Completely agree. I think people like to talk about their fears, and so the people who are more confident tend to be quieter during those conversations and prefer to just talk about something else. So there's a selection bias, where people talking about the weather tend to be the people who are most worried about it, so the conversation or consensus tends to a worried tone.

Sometimes this makes logjams of cruisers, where the folks who are comfortable with the prevailing conditions just go, and thus leave the conversation because they are gone. This leaves a group of people who are waiting together for a weather window, but all of the people in the little logjam or flock tend towards being very conservative with the weather, so it feeds on itself and their definition of a window is extremely conservative.