craw4d2003
Well-Known Member
Could anyone tell me which is the best and easiest to understand internet weather site to use for getting a 5 day weather window for the Bay of Biscay?
Internet weather site.........which is best?
- Thread starter craw4d2003
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ccscott49
Well-Known Member
I use, weatheronline.co.uk, wetterzentrale.de, and ecmwf.org, for my weather.
ecmwf has charts up to five days ahead, when I crossed biscay this is the site I used to check what was coming from USA.
ecmwf has charts up to five days ahead, when I crossed biscay this is the site I used to check what was coming from USA.
maxi77
Well-Known Member
I would agree with Englander, you need to use more than one and spend a bit of time before you need them understanding how good they are. For coastal work I have found http://www.windfinder.com/ quite usefull, and of course the met office marine forecasts as well as the ecmwf, which can show just how much the forecast synoptic chart forecast can vary even over 5 days.
markdj
Well-Known Member
I would use a combination of shipping forecast and GRIB forecast. Go to
http://www.grib.us
and get the software (requires free registration) and use that along with the shipping forecast from the met office which can be downloaded here...
http://www.opc.ncep.noaa.gov/shtml/UKMOFFAT
This full version of the shipping forecast includes sea state eg. smooth, slight, moderate, rough, very rough, high, very high or phenomenal; which I find very useful as an indicator while the girb gives the forecast in a very time accurate way.
Also of course is my own weather portal http://www.stronge.org.uk which has direct links to marine forecasts and synotic charts and a PDA/mobile page. I hope to update the mobile layout before the season starts.
http://www.grib.us
and get the software (requires free registration) and use that along with the shipping forecast from the met office which can be downloaded here...
http://www.opc.ncep.noaa.gov/shtml/UKMOFFAT
This full version of the shipping forecast includes sea state eg. smooth, slight, moderate, rough, very rough, high, very high or phenomenal; which I find very useful as an indicator while the girb gives the forecast in a very time accurate way.
Also of course is my own weather portal http://www.stronge.org.uk which has direct links to marine forecasts and synotic charts and a PDA/mobile page. I hope to update the mobile layout before the season starts.
FAITIRA
Well-Known Member
'weatheronline' and I tend to check it with 'windguru', I think they are all sourcing info from the same places, I just find these user friendly. Bill.
craw4d2003
Well-Known Member
Thanks to everyone for their replies, I shall be studying all the sites mentioned well ahead of time.
nickrj
Well-Known Member
http://www.passageweather.com is also good - It is basically graphic GRIB files with animations etc. But, you can also find those on Windfinder, which is excellent for coastal sailing. It runs off the weather buoys, so I guess just check the other buoys data nearby for the best picture of what's going on...
nick!
nick!
franksingleton
Well-Known Member
I know that I have said all this before in response to various discussions, but I keep seeing all the same discussion about the merits of the many ways of getting GRIB forecasts or forecasts derived from the US GRIB output from the US Global Forecast Sustem. I am trying to clear up what appear to be misconceptions that lead to muddled thinking. What it really comes down to is that you should use the service that presents the data in the form that you prefer, The forecsats themselves are identical or virtually so.
First and foremost, any GRIB type forecast whether UGrib, Saildocs, Movingweather, Windfinder, Windguru, Passageweather etc etc that offers forecasts worldwide, usually at grid points 1/2 or 1 degree apart or at specific points by inter[polation as Windguru or zoomed in as Movingweather WILL BE THE SAME. They are all using the US GFS output. They may format in different ways. There is no and can be no difference in quality of the forecast.
Secondly, forecasts that genuinely are at a higher resolution eg Poseidon, Theyr.net, Windguru when you pay for MM5 or whatever, Ilmeteo etc are all, as far as I know, starting from very poor initial conditions. From what I can see, and I have asked some of them the question directly, they all start from the same GFS output. They interpolate the GFS to whatever grid they use, usually about 0.1 degree ie about 6 NM.
That means that their models start with no knowledge of what effects topgraphy has had. True, they then take topography into account but that takes some 6 to 10 hours into the computaqtion before the models adapt. There can be problems in the computation because of the sudden introduction of topography.
Further, they start with no knowledge of small meteorological features.
However, even if (and it is a very big IF) these models were run from a good starting point, that is if they could analyse weather on the grid scale of their models, ( eg as the Met Office does for its Marinecall forecasts and its "Coastal Forecasts" on the BBC web site) there are still two overriding limitations on the forecasts. The Met Office puts more effort into data analysis than into the prediction itself. Given the models, running them is the easy part.
First, and most important to realise, any model can only represent weather and topography to a scale of about 5 times the grid length ie about 30 NM from a 6 NM grid. Secondly, small weather features have short life times. No model will predict much of the small scale detail that we observe.
I hope that this puts some of the discussion into perspective and underlines the need to interpret forcasts in general terms and after that use your nous. See my article in the last RYA Winter magazine. Although several organistions claim to be able to predict weather on very fine scales, it is simply not possible on a sensible time frame. We should all recognise that fact.
PS It is useful to compare the DWD 5 day forecasts that are on RTTY with the US GFS GRIB. Use either a HF/SSB receiver or the NASA Weather man to get these forecasts. There is a 3 day version on the Internet. It seems to me that the DWD give slightly better indication of mistrals etc than the GRIBs. I put this down to the Germans tuning tgheir forecast model to Europe while the US tune their's to the USA
First and foremost, any GRIB type forecast whether UGrib, Saildocs, Movingweather, Windfinder, Windguru, Passageweather etc etc that offers forecasts worldwide, usually at grid points 1/2 or 1 degree apart or at specific points by inter[polation as Windguru or zoomed in as Movingweather WILL BE THE SAME. They are all using the US GFS output. They may format in different ways. There is no and can be no difference in quality of the forecast.
Secondly, forecasts that genuinely are at a higher resolution eg Poseidon, Theyr.net, Windguru when you pay for MM5 or whatever, Ilmeteo etc are all, as far as I know, starting from very poor initial conditions. From what I can see, and I have asked some of them the question directly, they all start from the same GFS output. They interpolate the GFS to whatever grid they use, usually about 0.1 degree ie about 6 NM.
That means that their models start with no knowledge of what effects topgraphy has had. True, they then take topography into account but that takes some 6 to 10 hours into the computaqtion before the models adapt. There can be problems in the computation because of the sudden introduction of topography.
Further, they start with no knowledge of small meteorological features.
However, even if (and it is a very big IF) these models were run from a good starting point, that is if they could analyse weather on the grid scale of their models, ( eg as the Met Office does for its Marinecall forecasts and its "Coastal Forecasts" on the BBC web site) there are still two overriding limitations on the forecasts. The Met Office puts more effort into data analysis than into the prediction itself. Given the models, running them is the easy part.
First, and most important to realise, any model can only represent weather and topography to a scale of about 5 times the grid length ie about 30 NM from a 6 NM grid. Secondly, small weather features have short life times. No model will predict much of the small scale detail that we observe.
I hope that this puts some of the discussion into perspective and underlines the need to interpret forcasts in general terms and after that use your nous. See my article in the last RYA Winter magazine. Although several organistions claim to be able to predict weather on very fine scales, it is simply not possible on a sensible time frame. We should all recognise that fact.
PS It is useful to compare the DWD 5 day forecasts that are on RTTY with the US GFS GRIB. Use either a HF/SSB receiver or the NASA Weather man to get these forecasts. There is a 3 day version on the Internet. It seems to me that the DWD give slightly better indication of mistrals etc than the GRIBs. I put this down to the Germans tuning tgheir forecast model to Europe while the US tune their's to the USA
craw4d2003
Well-Known Member
Thanks
311260
New Member
www.movingweather.com is my favourite very easy to use and as mentioned above taken from NOAA just like the simplicity and animation
Cheers
Cheers
Saguday
Well-Known Member
Thanks Frank
franksingleton
Well-Known Member
It all depends on what you mean by best and what you want to use the site for. My own site tells you a great deal about weather and weather forecasting. It may or may not be the best site from which to access forecasts for your needs.
More importantly is the question of which are the best weather forecasts and that depends upon what you are using the forecasts for. My personal, some might say idiosyncratic, views are that sailors should always be using GMDSS forecasts because these are produced by intelligent human beings on the basis of computer output, They are essentially a warning service. There are links to these forecasts on my site and many others.
These can be supplemented by synoptic forecast charts, Again there are many links to these.
Secondly, I would put GFS or other global scale numerical weather prediction output for planning purposes and to help understand the GMDSS forecasts. I would add here the extended range 3 to 5 day forecasts that are on the UK NAVTEX 518 broadcasts but copied to the BBC web site.
Not an answer to your question, but a summary of what I think that a sailor should do.
Of course, when sailing, you should be monitoring VHF if near the coast, NAVTEX if further offshore and INMARSAT-C or HF/SSB broadcasts when on ocean passages.
More importantly is the question of which are the best weather forecasts and that depends upon what you are using the forecasts for. My personal, some might say idiosyncratic, views are that sailors should always be using GMDSS forecasts because these are produced by intelligent human beings on the basis of computer output, They are essentially a warning service. There are links to these forecasts on my site and many others.
These can be supplemented by synoptic forecast charts, Again there are many links to these.
Secondly, I would put GFS or other global scale numerical weather prediction output for planning purposes and to help understand the GMDSS forecasts. I would add here the extended range 3 to 5 day forecasts that are on the UK NAVTEX 518 broadcasts but copied to the BBC web site.
Not an answer to your question, but a summary of what I think that a sailor should do.
Of course, when sailing, you should be monitoring VHF if near the coast, NAVTEX if further offshore and INMARSAT-C or HF/SSB broadcasts when on ocean passages.
ski
Member
ACU and Windfinder seem to be the same. I notice that the MetOffice info for Poole is based a site in Hurn but ACU and Windinder's site is near Sandbanks. I wonder if this is why they dont always agree-
lenseman
Well-Known Member
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And once you have left harbour and have no access to the Internet, make sure you have a decent barometer with you and learn to use it on the hour, every hour. In this way you will see trends and can run into places like Cameret sur Mer, La Rochelle or Gijon as necessary!
I have an aneroid and also a Vion 4000 which wakes me with its bleeping when there is a sudden change.
I have an aneroid and also a Vion 4000 which wakes me with its bleeping when there is a sudden change.
A
Anonymous
Guest
When we wanted to cross Biscay I followed Frank's advice (above) and we used a combination of:-
Global Forecasting System via hf radio (saildocs) and Buoyweather. All the major Internet sites (e.g. Weatheronline) are just portals for GFS so take your pick and, as Frank has said, don't be suckered into thinking that you are getting more than you really are....all you are getting is the (freely-available public domain) GFS model. NO HUMAN FORECASTER. Can be horribly wrong.
Germany www.dwd.de Vital for Biscay - forecaster input
Met Office - Good Biscay forecasts - forecaster input
Meteo France - Good Biscay forecasts - forecaster input
Spanish Met Office - Good Biscay forecasts - forecaster input
By looking at all these weather forecasts and by ignoring the pleadings of my (getting frustrated) crew, we managed a good F4/5 beam reach most of the way across. We still had 60% fuel when we arrived at Gib, having sailed from Falmouth, and that included running the generator at anchor for a couple of weeks, etc.
Global Forecasting System via hf radio (saildocs) and Buoyweather. All the major Internet sites (e.g. Weatheronline) are just portals for GFS so take your pick and, as Frank has said, don't be suckered into thinking that you are getting more than you really are....all you are getting is the (freely-available public domain) GFS model. NO HUMAN FORECASTER. Can be horribly wrong.
Germany www.dwd.de Vital for Biscay - forecaster input
Met Office - Good Biscay forecasts - forecaster input
Meteo France - Good Biscay forecasts - forecaster input
Spanish Met Office - Good Biscay forecasts - forecaster input
By looking at all these weather forecasts and by ignoring the pleadings of my (getting frustrated) crew, we managed a good F4/5 beam reach most of the way across. We still had 60% fuel when we arrived at Gib, having sailed from Falmouth, and that included running the generator at anchor for a couple of weeks, etc.
