Med-specific (and extremely detailed!) weather forecasts

MapisM

MapisM

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A mate suggested me to check this out, and I found it worth a place among my other favourites.
Oh, and the Android/iPhone app is also very nice, btw.
So, I thought that some Med boaters around here might also be interested.
Not sure yet about its reliability, but if the 25°+ sea temperature predicted for tomorrow in my courtyard will be confirmed, it'll be a good start! :D
Apologies if already well known, but I can't recall to have seen it posted before...
http://www.sea-conditions.com/en/
SeaConditions_zps2e5683af.jpg
 
michaelchapman said:
You might also like to look at zyGrib (http://www.zygrib.org)

I use this and find it efficient over limited bandwidth internet connections (or when your are being billed for the amount of data you download).
Click to expand...

I assume you are using the Grib viewer
Did you know that you can load all this into OpenCPN and overlay it all on your charts as well.
 
MapisM said:
A mate suggested me to check this out, and I found it worth a place among my other favourites.
Oh, and the Android/iPhone app is also very nice, btw.
So, I thought that some Med boaters around here might also be interested.
Not sure yet about its reliability, but if the 25°+ sea temperature predicted for tomorrow in my courtyard will be confirmed, it'll be a good start! :D
Apologies if already well known, but I can't recall to have seen it posted before...
http://www.sea-conditions.com/en/
SeaConditions_zps2e5683af.jpg
Click to expand...

I like that site - it is quick to use
I useually use Passage weather but it is slow going through all the options.
Looks like a different model to the ones I use as well - most of the forecasts I use base themselves on the GFS

I'm off to try the Android version now
Thanks for sharing
 
Thanks Mapism but it has the same problem as other weather sites. I prefer websites that always forecast sunshine and F2 winds;)
 
Just loaded it on the Android phone and it works well on there as well.
When we are not going out for any distance, I like to look at cloud cover / precipitation
That way I get an indication if it is going to be sunny etc
Inside our lagoon, the wind isn't that much of a problem - but if it is overcast, it is probably better staying in the bar.
If there is rain about, you can get all kinds of local wind effects - again best to stay in the bar.
At this time of the year some of these localised rain storms can be quite fierce - and often carry thunder storms.
This site is dead easy to see all this quickly
Shame it only "runs out" 4 days - the GFS does a week.
 
Hurricane said:
Shame it only "runs out" 4 days - the GFS does a week.
Click to expand...
Funny you should mention it, have you ever found any forecasts which actually proved reliable for more than 3/4 days, in the Med?
Based on my experience, I don't think they are much better that tossing a coin....
 
I hadn't seen this before so thanks for putting this up MapisM, I like it and have also added it to my fav's. Very similar stuff on there to Passage Weather but much easier and quicker to use and read at a glance with everything on the same page, love the vivid colours. Agree with the >4 day outlook thing for the Med.
 
MapisM said:
Funny you should mention it, have you ever found any forecasts which actually proved reliable for more than 3/4 days, in the Med?
Based on my experience, I don't think they are much better that tossing a coin....
Click to expand...

The only forecast model I know that goes out to a week is the GFS
OK - it is not accurate after 3 days but, generally speaking, it does provide a very useful indication of what is to come.
Certainly worth building plans around it and then modifying them as the time frame gets nearer.

I definitely do consider the forecast a week ahead.
 
Hurricane said:
The only forecast model I know that goes out to a week is the GFS
Click to expand...
You might wish to check a couple of other sources which publish weekly forecasts:
www.windfinder.com
www.ilmeteo.it
The latter actually makes also 15 days forecasts, but I'm afraid the website is only in Italian.
Mind, while I find both these websites pretty accurate up to a couple of days or three, as I said I wouldn't hold my breath for anything longer... :)
 
MapisM said:
You might wish to check a couple of other sources which publish weekly forecasts:
www.windfinder.com
www.ilmeteo.it
The latter actually makes also 15 days forecasts, but I'm afraid the website is only in Italian.
Mind, while I find both these websites pretty accurate up to a couple of days or three, as I said I wouldn't hold my breath for anything longer... :)
Click to expand...

I'm no expert but don't all these forecasts base on the GFS model
Just checked Windfinder - and that does
Sorry, my Italian isn't up to reading the other one but these types of forecasts are usually GFS

Again, I'm no expert and haven't looked at it for a while, but aren't most of the Grib files that you can download based on the GFS as well.

I use Windguru a lot - and consider the WRF model against the GFS model
In the past, in the Med, both the GFS and the WRF have been fairly similar forecasts but this year, most of the time, they have been totally different.
When we were sailing in the UK, the GFS always seemed to underestimate - the WRF seemed to over estimate - this year the same seems to have been the case in the Med.

None of these forecasts, though, seem to take local geographical features into consideration.
There are other models - Passage Weather seems to handle COAMPS but I don't look at that much.

I don't think that the GFS or the WRF handle wave data so it is always useful to find a new one like this that gives a "big picture" of the sea conditions.
 
Well, fwiw "ilmeteo" website claims that they make their own forecasts, and occasionally I've seen some slight differences also in short term forecasts.
But it could well be that they use one of the most well known models as a basis, can't tell for sure.

...though having said all that, my favourite approach by far is the one I've been able to adopt since I escaped the rat race:
Wake up in the (late) morning, look around, and decide if and where to drop the hook for a swim! :cool:
 
I use Windfinder and then zyGrib to get the overall picture. If I see that the border between the area with F2 winds and F7 winds is close to my location, then I know to be very cautious with the Windfinder forecast which can easily be one or the other and has a high likelihood of being wrong.

Where I sail, we can have very big differences in wind (and waves) within a very short distance or short space of time due to local effects (the Pyrenees coming down to the water's edge). Neither Windfinder nor zyGrib fully take these effects into account and you get to learn when the forecast needs to be considered with care. It can easily happen that the center of the depression or the high pressure could be a few miles away from its forecast location. These circumstances can cause that F7 gale which was forecast only for areas N. of Cap Bear to descend easily as far south as Cadaques for instance. You could easily be looking at Windfinder thinking that you have F2 at Cadaques and the same F2 further north a Port de la Selva, and then find F7 on the nose when trying to make that passage.
 
At http://weather.mailasail.com/Franks-Weather/Grib-And-Objective-Forecasts-Reviewed, I give a list of all the objective forecast that I know about and relevant to European sailors.

For the Med, the best one should be that issued by Turkey - http://212.175.180.126/DTS/sea.php. It is output direct from the ECMWF. They use the most detailed global data analysis on a grid of 0.125 degrees ie around 15 km. It may not give the best forecast all the time but should be the best most of the time. It has wind and wave output as well as meteograms for named locations and wherever you click on the charts.

Big question – why cannot we get the same for areas west of Gibraltar? Write to the met Office and ask why not!
 
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