Weather Charts and Forecasting

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Weather Charts and Forecasting

Postby Vince Noir » Mon Dec 01, 2008 3:22 pm

Can anyone give me some sites and help with where to start doing my own surf prediction ?

. i.e. I'm fed up on relying with Magic

Although its useful, I Only use magic for the wind predictions, tides, and i check the swell forecast and spectral just to make sure there is some swell about

Once i've decided what the wind is probably going to do, i make my own decision based on the knowledge i have of my local breaks...for example, i know that my local needs SW swells.... W swells that magic might give 4 stars need to be huge before they wrap around properly, otherwise its flat.....or that if there is no swell whatsoever, but 15mph onshores, i know i can expect some surf

Apart from this http://www.ecmwf.int/ , which is kinda confusing, i dont know where else to get wave bouy data, wind predictions etc

Basically I'm looking to taking my "forecasting" to the next level, so if anyone could help me out, I'd be grateful
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Re: Weather Charts and Forecasting

Postby Ferral » Mon Dec 01, 2008 4:35 pm

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Re: Weather Charts and Forecasting

Postby Mat 'Sonic' Clark » Mon Dec 01, 2008 7:45 pm

For short range forecasting MagicSeaweed (MS) has just about everything you need. I especially like the near-shore forecasts for Fistral and Bantham. The Bantham forecast gives a pretty good indication as to whether or not swell will get into the south coast (I surf praa on the south coast normally and it tends to correlate quite well). It’s always been I nightmare to predict surf on the south coast and, although it’s not perfect, the MS near shore model really helps.

The only other WAM chart I look at regularly is

https://www.fnmoc.navy.mil/ww3_cgi/cgi-bin/ww3_area.cgi?color=b&area=natl

Swell Wave Height (ft.) and Direction


This is somewhat like the near-shore model as it filters out the low period wind swell. Also it’s based on the NGP weather model (not the best but okay for short range forecasts) so gives a slightly different take on things compared to the GFS model the MS info is based on.

The UKMET model is also worth a look. I tend to compare the MS wind chart with those on the BBC site(although the BBC charts seem to be a bit screwed and have been for ages).

For longer range forecasting compare GFS and ECMWF and perhaps take a look at the GFS Ensemble.
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Re: Weather Charts and Forecasting

Postby plappers » Thu Dec 25, 2008 5:45 pm

I disagree. There is nothing wrong with the model data. The problem with the MS near shore model is that is it resolved down from the higher resolution badly. What really needs to be done for the tucked away breaks in the south coast is a 'WRF model' rather than the basic apprach that MSW does. Last Monday was a classic example, the gridsquare that the forecast was resolved from for Praa was showing 12 secs and about 9 feet or something and there was less than a foot coming in. Its taking data from a grid square west of the lands end where there is swell but as praa is more tucked away than that particular square it can't wrap in. It worked well for the swell that is south of west (the 2 previous days) but when the swell turned more NWerly the foprecast was bad. A simple filter in which blocks out NW swell at praa would improve the forecast no end. Ben should be looking how a WRF model could improve the forecast. Basically what this does is 'nest' a high resolution forecast within the confinements of the mesoscale models. We do a lot of it at work for ports/windfarms power stations and the like and it works extremely well. Surfing beaches could utilise the same princple.
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Re: Weather Charts and Forecasting

Postby Chai Wallah » Thu Dec 25, 2008 6:34 pm

Plaps - you should be drinking and trench filling rather than thinking about work at this time of pagan worship. Anyway hope your prediction for waves at reefs on Friday come off
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Re: Weather Charts and Forecasting

Postby Barneyrubble » Thu Sep 17, 2009 8:05 am

Mat 'Sonic' Clark wrote:For short range forecasting MagicSeaweed (MS) has just about everything you need. I especially like the near-shore forecasts for Fistral and Bantham. The Bantham forecast gives a pretty good indication as to whether or not swell will get into the south coast (I surf praa on the south coast normally and it tends to correlate quite well). It’s always been I nightmare to predict surf on the south coast and, although it’s not perfect, the MS near shore model really helps.

The only other WAM chart I look at regularly is

https://www.fnmoc.navy.mil/ww3_cgi/cgi-bin/ww3_area.cgi?color=b&area=natl

Swell Wave Height (ft.) and Direction


This is somewhat like the near-shore model as it filters out the low period wind swell. Also it’s based on the NGP weather model (not the best but okay for short range forecasts) so gives a slightly different take on things compared to the GFS model the MS info is based on.

The UKMET model is also worth a look. I tend to compare the MS wind chart with those on the BBC site(although the BBC charts seem to be a bit screwed and have been for ages).

For longer range forecasting compare GFS and ECMWF and perhaps take a look at the GFS Ensemble.


I think MSW probably serves the main spots down south better than other spots up North - most of us up from Cornwall don't have that nearshore data stuff. Also, on countless times, MSW predicts bog all on my main spot yet there are good (maybe small) surfable waves loads of times. The stars stuff just doesn't work for me. Windguru is more accurate. Shame as MSW has the most user friendly format and all the charts in one place.
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Re: Weather Charts and Forecasting

Postby Mat 'Sonic' Clark » Thu Sep 17, 2009 10:48 pm

If the predicitions for your main break don't seem very accurate its probably best to look at the WAM height and period charts themseleves and get feel for what leads to good conditions.
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Re: Weather Charts and Forecasting

Postby plappers » Fri Sep 18, 2009 8:24 am

Again - you are confusing things here again - both wind guru and MSW use the same model data so the forecasts will be more or less the same -value is added only when you filter out the noise in the nearshore environment and neither MSW or wind guru use the right methodology to get this right.

Rather than resolving down fom a lower resolution, they should be running WRF or a compass rose filter to refine the forecasts in the NS environment as both techniques are proven to be very reliable the best. Also ECMWF has the best ocean forecasts and this data would greatly improve the forecasts.
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Re: Weather Charts and Forecasting

Postby skimmer2 » Wed Sep 23, 2009 8:00 pm

Mat 'Sonic' Clark wrote:If the predicitions for your main break don't seem very accurate its probably best to look at the WAM height and period charts themseleves and get feel for what leads to good conditions.


Agree...that's where I'm heading. I use MSW/Windguru as a bit of a base to work from and learning the other stuff...slowly though.
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