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Wylieguy
07-23-2009, 10:22 PM
Hey, Any experienced weather folks want to begin talking about the weather we might expect out beyond the 60 mile "local" NOAA forecast?
Pat Broderick, "NANCY"

tiger beetle
07-23-2009, 10:36 PM
Hey, Any experienced weather folks want to begin talking about the weather we might expect out beyond the 60 mile "local" NOAA forecast?

Hi Pat- you could check out the high seas forecast to 250 miles, and the computer model grib files now extend beyond race start.

It's a bit early to make much of a weather call, other than to point out that nothing bad is showing up on the forecasts: winds 15-20 knots, seas 8-10 feet. Nobody is calling for a sustained coastal gale at this time.

Forecasts should begin to firm up Monday, and at that time it will be interesting to see what NOAA/NWS thinks will be happening offshore.

- rob

Alchera
07-23-2009, 10:37 PM
Hey, Any experienced weather folks want to begin talking about the weather we might expect out beyond the 60 mile "local" NOAA forecast?
Pat Broderick, "NANCY"

Well, it's a bit early to say for sure, but the long range gribs are showing a nice 10-18k out of the NW for the race timeframe. That would be really nice.

- mark

tcuevas
07-27-2009, 03:53 PM
Any routing suggestions for us first timers. The trip out has me questioning myself, I have the basic concept "go west as fast as you can." Which is on a reach but that is to some extent take us to the south. What I am wondering about is how far south are we going to get? I realize that as we get further out we will get lifted but there has got to be the risk of being too far south? When should I start to think i have gone too far south? :confused:

BobJ
07-27-2009, 05:14 PM
Welcome to the board, Poco Loco!

The current forecast would put you on a beat all the way out, but you'll get there faster sailing cracked off (even with the greater distance). "Cracked off how much?" will be answered by the boat's polars.

A quick-n-dirty approach would be to put a point in your GPS at 126 40 and what, 37 50 (whatever we are here), then watch your ETA to see when you are at the optimum cracked-off angle.

tiger beetle
07-27-2009, 10:01 PM
When should I start to think i have gone too far south? :confused:

When you see penguins!

Looking at this morning's forecast, there are two features at play, and navigating through the weather systems' movement will be an interesting part of the LongPac.

The Pacific High is west and forecast to spread out and move further west, and the inland Low is forecast to move out to the coast. This will probably change with tonight's forecast, and several times again before race start. The probability of accurate forecasting increases as we get closer to race start, but the only accurate weather is what you can see from the cockpit and the buoy reports.

On the way out you can essentially go anywhere, but on the way back your route is constrained because you need to re-appear at the Golden Gate Bridge. As a result, it is possible to work backwards on this race:

1. at what latitude do you want to cross 126.40 longitude?
2. how best to get to the latitude?

I will not know what I will do until I clear Point Bonita, therefore I cannot today tell you what I intend to do Wednesday noon-ish. Sitting here at the dock I have run through a series of scenarios using Beetle's polars evaluated against the grib files - resulting in perhaps three or four different routing possibilities. The initial decision is to select one of those routes on the way out towards the light bucket, and then to listen to VHF weather, the buoy reports, look at the weatherfax reports and grib files to continually refine the route and generate more possibilities; for TransPac I would do this twice daily; on this race I will perhaps do this more often as the race happens in a much smaller area, on a shorter time frame, with more weather data available than is available mid-ocean.

Alternatively I might just pull out a book and let Beetle run west!

- rob

BobJ
07-27-2009, 11:17 PM
I'm not racing this one so I don't have to be as cryptic.

Try this site. (http://www.passageweather.com/)

Click on the big blue box, then the smaller dark red box, then on "Animate" and watch what happens. It looks like the direction (NW) will stay pretty constant but things will get a lot lighter if you're not back by Sunday.

As I told a couple of racers tonight - take a couple of books to read.