Weather and Forecasts

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cpedw
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Weather and Forecasts

Post by cpedw »

I have been advised by several sources that XC Weather is a reliable forecast. This disappointing season, I've found that XC has regularly seriously underpredicted wind strength. Other aspects of their forecasts have been reasonably accurate. Later in the season, I've been relying more on the Met Office but their presentation is a lot less easy to interpret.
How have you found the forecasts?
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BlowingOldBoots
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Re: Weather and Forecasts

Post by BlowingOldBoots »

Fine. I use Predict Wind, Met Office, plus Shipping Forecast via NavText.

They basically predict reasonably well and I am not particularly interested in pin point accuracy. Compared to 20 years ago, we have easy access to weather predictions. I think there is a lot of misplaced belief that the models from any vendor will be, or rather should be, accurate. It is just as inaccurate today as it ever was.

Also most of the raw data for the model, or the base model used to build and tweak other models from, only comes from a few sources, so everybody is really using the same data, just presenting it differently or adjusting based on how they think a model should work.

I tend to focus on UKMO and ECMWF.
What's that? Dunno! Should we be worried about that? Dunno! How? Ah dunno!
Gardenshed
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Re: Weather and Forecasts

Post by Gardenshed »

XC is solid and reliable but as it uses a larger grid (cheaper data) and longer time period than other apps (with no gusts being shown). those averages will typically reduce the wind speed shown. Use it for nervous crew.....

I use Windy as a starting point. It allows you to select from the different weather models (ECMWF, GFS, ICOn-EU and NEMS) and directly compare. The closer they are, the more confidence you can have.

You can also go from sea level up to 40,000ft plus, showing the weather systems above the distortions of the land and hills, that gives an improved picture of what's impacting the weather at sea level. Moving the time-line shows the likely speed of movement of the systems.

If you pay for a subscription (e.g. predict wind premium) then you get access to the more accurate, smaller grids used for the data collection. That improves accuracy.

is one app better/worse than the others? not really, all have strengths and with today's ease of access, its worth comparing as many as you can make the time to look at

All are forecasts with varying degrees of inaccuracy
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wully
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Re: Weather and Forecasts

Post by wully »

Sailie, windsurfing, kite sites over estimate wind speed in my (auld fart )long experience.

All forecasts are guesstimated from one of two global models so are only predictions.

XC is good as is Windy.

Both are heavily compromised by local effects that you NEED to be familiar with to get a decent local forecast.

The weather is the weather. Some geek with a selection of variously coloured pens in his shirt pocket in an office cannot predict what you are going to get wherever you are so take a look outside then decide for yourself…
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Nick
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Re: Weather and Forecasts

Post by Nick »

Windy allows you to switch between models, even on the free version. (XC uses GFS for the free version and I have not found any way to change this.)

If GFS and ECMW models agree closely then you can have a lot more faith in the forecast.
- Nick 8)

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Bodach na mara
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Re: Weather and Forecasts

Post by Bodach na mara »

I have the XC app on my phone and refer to it. But I take the results with a pinch of salt. I feel that it is as good at predicting the weather was horoscopes are at predicting my future.
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Re: Weather and Forecasts

Post by Mrmickey »

I’ve had similar experiences with XC Weather it's usually good for a quick overview, but I’ve also noticed that the wind strength can be off. I often cross-check it with Windy or the Met Office for a more accurate picture, especially if I’m planning a longer trip. The Met Office does seem to be more reliable, even if their interface isn't the best. For me, using a combination of apps gives a clearer idea of what to expect, especially when the weather’s unpredictable. How have others been finding it this season?
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