[cthoops]

Now that the rainy/windy 4th of July has passed, I'm hoping to get out on the water for what's left of the holiday weekend. However, the wind forecasts on the various sites and apps that I'm looking at are varying widely.

NOAA marine is saying 8-11 knots tomorrow and 7-12 Monday, both days with seas 1 ft or less. Sailflow is showing winds getting up to 18 mph with gusts in the high 20's and 2 foot seas by later tomorrow afternoon and a similar outlook for Monday. Predictwind is similar. Big difference, especially when we were planning on having newbie friends with us.

Generally I haven't found there to be such a wide variation from NOAA, but this is also only our second season owning a boat and our first time having a storm like Arthur pass this close off of our coast.

So which sites have you found to be most accurate, and which one do you think is right this time?

 

[jsaronson]

Passageweather.com gives two different models. WindAlert and wind guru can be good. No one site is great all the time.

 

[svHyLyte]

Passageweather.com gives two different models. WindAlert and wind guru can be good. No one site is great all the time.

Two thumbs up for PasssageWeather which we've found good for up to 5 daze out...

 

[Sal Paradise]

There is going to be a lot of west wind today. I would use the higher numbers.

 

[Alex W]

Wind forecasting is the least advanced model of the weather forecasting models. Most people don't care about the difference between 12mph and 18mph of wind, so the models aren't tuned very well to predict it. Sailors care a lot, but there aren't many of us.

Around here (Seattle) I look at the University of Washington and NOAA models, but mostly I keep an eye on the weather stations on Puget Sound. A big factor here is the Puget Sound Convergence Zone and looking at the current wind readings can help me understand if that is going to be a factor or not.

 

[Sal Paradise]

Did you check the buoys?

NDBC - Station 44039

 

[MarkofSeaLife]

Passageweather, windguru and NHC using its tropical weather discussion page Surface Analysis page http://www.nhc.noaa.gov/tafb/USA_12Z.gif

 

[outbound]

Went day sailing today in area discussed by o.p. Ended up anchoring in near by town not wanting to dock in such wind Saw 30-35kt and wife said she saw 42 in a gust. These are tws numbers off the raymarine. Metereoman doesn't, show the change expected for such winds. They all stink or on are spot on depends on the day. Still like passage weather the best so far.
Don't understand why such winds with this system. But don't understand the 500mb yet either.

 

[CaptainChaos]

I like PredictWind for offshore. Haven't used them too much for coastal but they seem to be relatively accurate in the Chesapeake over the past week or so.

 

[TQA]

I like Windguru and find it accurate on wind speed gusts and direction. It is much less accurate on precipitation but who cares.

On the odd occasion I need to see the bigger picture I use Passage weather.

For the really big picture when there is something nasty brewing near the Cape Verdes Stormcarib has a page that shows lots of satellite views.

 

[theonecalledtom]

If you pay for Sailflow it offers a lot of information. I'm not sure what comes as standard but I think I can side by side graph about six models for my local area.

Having used this for several years it's seemed more accurate in recent times but I've definitely had it diverge significantly in both directions, erring on an over prediction in normal conditions and an occasional under prediction in more severe conditions.

Just started looking at predictwind. I like the simple interface but in its first major divergence to Sailflow Sailflow was more accurate. Will be monitoring this more later this year to see if I can feel the more accurate.

The longer the trip the more I cross reference noaa, weather.com, etc and they all seem equally semi accurate - will try some of the sites mentioned above.....

 

[SuperV]

We used Passageweather, Windguru and Buoyweather on our way from Guatemala to the Chesapeake. All of them were wrong predicting wind speeds in Belize, where we hit some nasty weather that lasted over night. Windguru's prediction seem to be limited to small geographic areas, so getting the big picture in Passageweather was nice, as well as having info on the gulf current and isobars.

 

[RTB]

Windfinder has been accurate for us (most of the time) during our 19 months of cruising. I do look at passage weather and download Ugrib files. If these all vary, listen to the little voice that says "wait a day or two".

Ralph
New home | sailing away with R & B

 

[Sal Paradise]

Went day sailing today in area discussed by o.p. Ended up anchoring in near by town not wanting to dock in such wind Saw 30-35kt and wife said she saw 42 in a gust. These are tws numbers off the raymarine. Metereoman doesn't, show the change expected for such winds. They all stink or on are spot on depends on the day. Still like passage weather the best so far.
Don't understand why such winds with this system. But don't understand the 500mb yet either.

Same thing here. Crazy gusts yesterday that I could see coming way off then the wind would veer and die. Downwind my GPS was showing 7 mph - for a Cat 22.. Sailflow showed a spiky gusty pattern up to 25 mph. Tried to beat back against it and my wife got so scared she went into the cabin and wouldn't come out so I dropped the sails and motored back to the dock.

 

[Minnewaska]

Tropical systems always, always, always throw the local wind models off. Before, during and after. Direction is fairly accurate, but velocity can be severely affected by position, direction and speed of the storms track. Small variables can significantly impact local winds.

 

[smurphny]

NOAA wind forecasts are almost always inaccurate. Local wind can vary tremendously which is why local knowledge is so important. It is also the most difficult to obtain when in an area you're not familiar with. I find that NOAA Surface Analysis, when combined with 500 mb. charts are the most useful for making decisions as to whether to go or stay put. They are also available anywhere via SSB whereas many of the others are not. The 500 mb charts give a good picture of the general direction and intensity of surface system movement. This piece about the 500 mb charts is very useful:Mariners Weather Log Vol. 52, No. 3, December 2008

 

[Sal Paradise]

I agree . Surface maps can tell you about what the trend will be - 1, 2, 3 days out - and what to look for during the day. Although we all knew things would be trending better, it didn't tell us if we could go yesterday or not.

 

[smurphny]

I agree . Surface maps can tell you about what the trend will be - 1, 2, 3 days out - and what to look for during the day. Although we all knew things would be trending better, it didn't tell us if we could go yesterday or not.

Were you on LIS? If so, that's a perfect example of local knowledge trumping overall forecasts. On the backside of a low pressure system, that kind of gusty condition is very typical on the Sound. As an indicator, a specific type of cloud, as a front moves out, indicates incoming high wind. Seeing small, thin, broken, BLACK, lower level, clouds coming over the the horizon from the north always indicates building high wind and gusty conditions.

 

[weinie]

I'm liking sailflo myself. I kinda like the graphs they use to show wind predictions over the next few hours and days, right along with the wind direction and waves heights, etc.

Secondly, they have a great app for android which tells me what the wind is doing at the observation point of my choice. It's right their on my home screen...don't even need to push a button!

 

[zeehag]

i use not one accurate assessment for furycames only, as they live up to rep on local stuff. passage weather does just fine here in west coast--even to seeing stuff the nhc models do not see, and being correct in this...lol.....once i saw a discrepancy in intensity of papagayo, but we allknow chubasco, papagayo an d tehuanos are intense and more than expected. and so it goes..... storm 2k for intensity and prediction of furycames..if they cheer--we gonna die.. and they are gooooood fro named storms and predictions therof.
also on this west coast is sonrisanet.org, which is a l¡l slower at the tropical predictions, as he gets form all other sources and combines for a good reporting of weather and predictions forthis side of earth. but i still use passage primarily here