Swell prediction in South Biscay

[snorkmaiden]

I am aware of the websites that give swell predictions - my question is specifically what conditions in the Atlantic mean that we will have dangerous onshore swell on the Northern coast of Spain (Asturias)? We will have access to Navtex and possibly Spanish VHF weather bulletins as we approach the coast. At the moment there is no sign of a settled Atlantic high. I want to know what to watch for - deep low pressure centres? How fast does swell approach from a centre of low pressure. Anything else about the Asturias Coast - Gijon to Santander.

 

[SHUG]

Just go to http://www.passageweather.com/ and allow it to scroll through "Wave height" charts for your area for the next five days and I think you will be able to work it out by also looking at the synoptic chart.

 

[LadyInBed]

I was told,watch out if swell is over 3 mtrs.
A good android app is Metio Consult Marine
https://play.google.com/store/apps/details?id=com.lachainemeteo.marine.androidapp

 

[ribrage]

There is also a couple of weather buoys out in the bay that are on the met office website , look for the observations page , quite useful info

 

[Nostrodamus]

There is a program called Buoyed weather which uses boys out in Biscay. It is pretty accurate and you can use it to do passage planning across as it will give you the expected weather at certain positions along the way. I believe you can get a months free trial

 

[macd]

One thing to watch for along that coast is significant swell opposed by local wind (and hence local waves), which is not uncommon when the Iberian low is well established: it gives a confused, lumpy sea which can be unpleasant, if not usually dangerous.

 

[Sandyman]

There is a program called Buoyed weather which uses boys out in Biscay. It is pretty accurate and you can use it to do passage planning across as it will give you the expected weather at certain positions along the way. I believe you can get a months free trial

This one ? http://www.buoyweather.com/index2.jsp

 

[Nostrodamus]

This one ? http://www.buoyweather.com/index2.jsp

Yes that is the one... because it uses buoys off the coast you get a good indication of the swell. At least there is a 16 day free trial to see if it works for you.
We found it to be very accurate.

 

[ribrage]

I used to get that via work ,then the cheap skates cancelled the subscription....they sold the business for 1.2 BILLION - but wont give me decent weather forecasting services ...ask the bridge is their usually retort !

 

[Roberto]

Yes that is the one... because it uses buoys off the coast you get a good indication of the swell. At least there is a 16 day free trial to see if it works for you.
We found it to be very accurate.

What they call "virtual buoys" are simply model interpolations for whatever coordinate one chooses, their site indicates the model run being used...

"Real" buoys report obviously recorded condtions only, not forecasts: type 62001 ("Gascogne" buoy) and choose the product here
http://www.meteo.shom.fr/qctools/dataplotsurfmar.htm
or here depending on the type of display you prefer
http://www.ndbc.noaa.gov/station_page.php?station=62001
They give prevalent wave height, period and direction, so it has some usefulness just bear in mind the values are average of combined swell and wind-driven sea state.

The Spanish forecasts by VHF (or navtex) indicate swell height: "mar de fondo", it's easy to distinguish as "mar de fondo" is expressed in metres, while live sea state in DOuglas (marejada, fuerte marejada, gruesa, etc).

Should you have internet access, this product is interesting for the northern coast of Spain, as it differentiates between swell (white arrows) and live sea state (green arrows): look here for example some cross sea is forecast (green arrows perpendicular to white ones) for Cape Finisterre area

( the image may have changed when you have a look)
anyway, full set of charts here:
http://www.puertos.es/sites/default/files/contenidosExternos/Predolas/mapas_todas_cant_h.html

This one instead gives individual forecasts for local ports (Gijon, Aviles, etc), this an example of cross seas around Gijon

http://www.puertos.es/content/prediccionlocaldeoleaje

 

[emandvee44]

http://www.hidrografico.pt/boias-ondografo.php

This is useful if you are a bit further South.

M.