XCWeather says, Metcheck says...

AngusMcDoon

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XCWeather forecast for Aberdaron said last night 36mph for this morning.
Actual reading from XCWeather...38mph.

Metcheck said last night 16mph for the same area.

What's happened to Metcheck? They seem to have lost the plot completely for windspeed forecasts.
 

dunedin

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I love the way xcweather gives a visual overview of the position, and tends to be as good as any. Always use a mix of this plus official Met Office Inshore Waters.

Some knowledgable weather chappie said windguru uses a very wide spaced grid so less accurate than Met Office. But the Met simply hedge their bets such as "8mph gust 30 mph" so not sure what that tells you other than "we don't know"
 

prv

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Some knowledgable weather chappie said windguru uses a very wide spaced grid so less accurate

If you give WindGuru a couple of euros you get access to higher-resolution forecasts.

Haven't been doing so for long enough to assess how much more accurate they are.

Pete
 

bluedragon

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If you give WindGuru a couple of euros you get access to higher-resolution forecasts.

Haven't been doing so for long enough to assess how much more accurate they are.

Pete

Been using Windguru-pro (hi-res) for years. The best out there IMO, although the free Windfinder "super forecast" is also hi-res it seems and very good.

PS - both the above got Plymouth Sound spot-on at midday today with around 23kn building to 26-27kn for a while. These weren't gusts but an "average" I read from our anemometer. Don't know what XC said (but they use the coarser GFS data similar to Windguru-free and that suggested 17kn if I recall)
 
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franksingleton

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XCWeather and others

I cannot comment on the provenance of the forecasts provided by Metcheck. Ask Simon Keeling. But, in order to be able to produce a forecast for any location, it can only come from an automated forecast system,

Those that give forecasts globally are almost invariably, the US GFS simply rehashed in some form or other. XCWeather is the GFS interpolated from a ½ degree grid to specific points – observing locations. It is precisely the same information as from Movingweather who also use the GFS presented in their format. Magic Seaweed is another source of highly jazzed up GFS forecasts.

Perhaps the best aspect of XCWeather is that it is the most easy way of getting all the latest actuals. The Met Office site has a good page of marine actuals updated hourly.

To get the GFS, I normally use zyGrib – see my page at http://weather.mailasail.com/Franks-Weather/Zygrib-Ftp-Grib-Service and related pages on many, by no means all GRIB type services. zyGrib is free – why use Movingweather? Ugrib is another freebie, same information.

WindGuru and some others also provide forecasts that are re-hashes of the GFS as freebies. They and others also run meso-scale models where they run a model that starts with the GFS but calculates over a smaller area on a finer grid. The models are OK but, unlike the big boys (eg US, UK France Met services) they do not, as far as I am aware, put in more data. As a result, I am never sure what these forecasts can really do to generate better forecasts than the GFS... I suspect that they may do better sometimes.

Anyone wanting to see the mass of data that are available might like to put a cold towel on and see http://weather.mailasail.com/Franks-Weather/Weather-Observations-Nwp
 

snowleopard

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The big drawback of XCWeather is that most of its forecast locations are on land so tend to substantially underestimate nearby sea conditions. Remember it is aimed at hang-gliders. I tend to pick the nearest offshore or island location.

Passageweather is very good, particularly as it gives an idea of variations over an area. It also goes out to 180 hours ahead
 

savageseadog

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XCWeather forecast for Aberdaron said last night 36mph for this morning.
Actual reading from XCWeather...38mph.

Metcheck said last night 16mph for the same area.

What's happened to Metcheck? They seem to have lost the plot completely for windspeed forecasts.

Ah but what was the true wind speed? I've queried the Aberdaron readings on XCweather before, they always seem significantly higher than they should be. Some forum members suggested it was because the weather station was in an exposed spot. I stand by what I say and have wondered if the readings are mph rather than knots at the very leaset.
 

Clyde_Wanderer

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I use XCW Weather,Windfinder too, but my favourite is
Wind Guru. Any comment?

Yes I use Windguru too and find it accurate, also easy to print off take with me so I can check its accuracy and what to expect.
Agree with Metcheck wind forecasts way out, that's when you can actually get on to the site.
Passage weather is good too.
 

franksingleton

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Ah but what was the true wind speed? I've queried the Aberdaron readings on XCweather before, they always seem significantly higher than they should be. Some forum members suggested it was because the weather station was in an exposed spot. I stand by what I say and have wondered if the readings are mph rather than knots at the very leaset.


Oh. Do you mean the actuals? I thought that you meant the forecast.

If you mean the actuals, then the observation is Aberdeen Airport (Dyce). It should be an accurate measurement averaged over 10 minutes. How representative it would be of conditions over the sea, I do not know. I would have thought pretty good, but cannot be sure ie cannot remember from my days as a forecaster.
 

BrendanS

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Frank, your inputs to ybw forums are wonderful. I'm pretty up to date on such stuff, but it's great to have everything clarified so succinctly
 

VicS

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Currently forecasting 96mph for Ilfracombe for this Friday!:eek:

Similar ( 90mph) for the solent. In fact winds in excess of 70mph on Thursday though Sunday

making up for the light winds forecast for the weekend just past perhaps.

It's a useless site when it outputs this sort of garbage you cannot have any confidence in it whatsoever.
 
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