SailNet Community banner

1 - 12 of 12 Posts

·
Registered
Joined
·
122 Posts
Discussion Starter #1
Okay, all you old salts know exactly what I'm talking about: charts that feature the little "musical-note" symbols, which tell you how much wind is typical, from what direction, at what time of year ...

What do you call these "maps"? Can they be found online? I'll need to learn to use them to prepare for an upcoming circumnavigation in my Catalina 22. :svoilier:




(YES I'm kidding about that last ... but I do want to learn about them ... thanks!)
 

·
Registered
Joined
·
2,861 Posts
If you want to use the old antique type weathers charts our Government still uses them go to NOAA.gov/weather. but a lot of sailors today use web sites like Sailflow.com much easier to use and read.
 

·
Registered
Joined
·
1,341 Posts
You could use any number of apps for PC, iphone, Android, etc. that has the wind data info you seek... this is just one of many but will give you clues to use. I would get Chapman Piloting or some other book that has an extensive section on reading weather maps.

Buoyweather | Accurate Marine Weather Forecasts.

Others may have more specific info regarding weather applications and their interpretation of the those 'musical note flags' you mention.
 

·
Old as Dirt!
Joined
·
3,483 Posts
Okay, all you old salts know exactly what I'm talking about: charts that feature the little "musical-note" symbols, which tell you how much wind is typical, from what direction, at what time of year ...

What do you call these "maps"? Can they be found online? I'll need to learn to use them to prepare for an upcoming circumnavigation in my Catalina 22. :svoilier:




(YES I'm kidding about that last ... but I do want to learn about them ... thanks!)

They are known as Pilot Charts, published by month. They can be found at (click on) NGA Atlas of Pilot Charts.
.

Select the region and time of year you're interested in. The "wind roses" show the direction of winds by percentages and the "feathers" on the arrows, their average force.
 
  • Like
Reactions: RichH and dixiedawg

·
Registered
Joined
·
146 Posts
Look at passageweather.com and pick out the map relevant to your area of operation. The wind maps can be animated or advanced frame by frame, but be aware that the information is for GMT so you have to convert that to your regional time zone. They basically take the publicly available data from NOAA and give you hour to hour weather charts. It is a good tool not only for planning your trip but also studying the weather and typical wind patterns during the day for someplace you are trying to learn about.
 

·
Registered
Joined
·
122 Posts
Discussion Starter #7
They are known as Pilot Charts, published by month. They can be found at (click on) NGA Atlas of Pilot Charts.
.

Select the region and time of year you're interested in. The "wind roses" show the direction of winds by percentages and the "feathers" on the arrows, their average force.

Ah, yes! "PILOT charts", that's it!! THAT'S the word I was trying to remember, and without it, google was not helping much. LOL

Thank you, and thanks everyone!!
 

·
Noah's Bosun
Joined
·
236 Posts
Unasked for trivia.... The "Pilot Charts" have been compiled from ships logs starting back during the days of the British Admirality thru the present. Several hundred years of observations of wind and current in a given location on a given date are used to compile the info shown on the charts....
 

·
Mermaid Hunter
Joined
·
5,689 Posts
Okay, all you old salts know exactly what I'm talking about: charts that feature the little "musical-note" symbols, which tell you how much wind is typical, from what direction, at what time of year ...
As others have noted they are called pilot charts. As Cap-Couillon notes they are based on hundreds of years of data. It is pretty clear that there have been changes in that time. Jimmy Cornell has an updated global set of pilot charts based only on the last 70 years or so and dominated by satellite data collection. Highly recommended.

Look at passageweather.com and pick out the map relevant to your area of operation.
Except that Passageweather is based entirely on GRIBs - the direct output of a single computer model untouched by human hands. Artifacts we care about like cold fronts are not reflected.

Synoptic charts that are developed by real live meteorologists based on multiple models, weather balloon reporting, overhead visible and IR and radar imagery, and ship reporting are better.

See AuspiciousWorks - Communications / Yacht Management / Deliveries Worldwide
 

·
Bristol 45.5 - AiniA
Joined
·
4,526 Posts
There is a bit of confusion in this discussion between weather and climate. Pilot charts show climate patterns - long term averages of winds and other conditions. On the other hand GRIBs, Passageweather, and the like are weather maps. They show current and predicted (for a few days) wind conditions. These might be very different than the long-term averages shown on pilot charts. Both of these are very useful but they fundamentally different purposes.
 

·
Registered
Joined
·
122 Posts
Discussion Starter #12
There is a bit of confusion in this discussion between weather and climate. Pilot charts show climate patterns - long term averages of winds and other conditions. On the other hand GRIBs, Passageweather, and the like are weather maps. They show current and predicted (for a few days) wind conditions. These might be very different than the long-term averages shown on pilot charts. Both of these are very useful but they fundamentally different purposes.

You are correct, sir. Climate data is all I'm interested in, not weather, as far as my original question is concerned. For long-term planning. Which way does the wind blow in Port-aux-Francais in February, and how strong is it ... that sort of thing.
 
1 - 12 of 12 Posts
Top