Predict wind PWE or PWG?

[stu9000]

Hi
I've used wind finder and windy in the past and they are good. But I've been playing with Predict Wind which is similar but seems to have more sources of weather data.
These ECMWF and GFS sources don't agree for next weekend ?.
Which do people find to be more reliable in the Thames area?
I'm leaning towards ECMWF (and the PWE predict wind interpretation of it).

 

[zoidberg]

Next weekend..... five days and more away.

Small initial differences in starting data lead to rather larger divergences '5 Days Out' and more.

Copy the competing forecasts as of today, then every twelve hours, drawing comparisons as you go. By mid-Wednesday they should be converging again. If not, and it's significant to what you intend, make your decisions around the less favourable offering - but then observe for your self what actually happens and be prepared to switch your approach.

 

[Ammonite]

I'm a fan of the (free) predict wind app and use it all the time to compare the UKMO, ECMWF and GFS models for the Solent and South Coast but I can’t get my head around the PWE model. For example, the forecast for the area just outside Portsmouth harbour at 11.00am on Thursday the 10th October is F4 gusting to F5/F6 according to the ECMWF and UKMO and F8 gusting F10 according to the PWE model and I've noticed similar discrepancies on several occasions with the PWE seemingly predicting severe weather that doesn't materialise. I generally just ignore it if the other models differ and are in broad agreement but I'm still puzzled why it seems so at odds with the other models on a regular basis

 

[Porthandbuoy]

I've been using Predict Wind for years on the basis that if the computer models are in agreement then I can have confidence in the forecast. That's usually good for a 3 or 4 day lookahead, beyond that they often drift apart . . . . . . and I go by the most optimistic one

 

[Ammonite]

Even on Wednesday evening its predicting F7/F9 against F3/4 gusting F4/F5. Maybe it's the hovercraft

 

[wonkywinch]

Use the one you like the look of

I don't trust any forecast more than 3 days out, preferring to look at the synoptic chart and work things out for myself. As an example, here is today's synoptic.

Surface Pressure Charts

This week will be rubbish for the south UK. The presence of the low SW of Ireland (an old tropical storm) followed by storm Kirk, the uncertain track of which will result in conflicting models but certain of some wind and rain by the end of the week, I know to get on with inside jobs.

 

[wonkywinch]

To add to my post, if you click the "Black and White" tab on the met office site, you can see the table, top left for the geostrophic wind (approx 2,000 feet high). Measure the space between the isobars (lines of equal pressure, 4mb apart on met office charts) then transpose that to the geostrophic wind scale at the latitude you are measuring (in this case c 52N) and read off the wind speed.

In this case, the south of the UK will experience a geostrophic wind of SSW around 17/18kts. Winds run anticlockwise around a low pressure due to coriolis force. Wind at the surface is less due to friction which also causes it to back, so expect a southerly around 10-15kts along the south coast today.

And yes, the winds around Kirk are c 80kts!

 

[dunedin]

This is an old thread restarted - but probably still relevant.
I also use PredictWind but, at least in Scottish waters, I ignore the PWE/PWG rows (often outliers) but instead use the other rows - GFS, ECMWF, UKHOx2 and Spire.
As ever, a consensus is good, a wide range a warning to expect the unexpected.

 

[papaver19]

I used the ECMWF reanalysis product professionally (I was a "science hippy", as Ze Frank calls us) and it's generally acknowledged (even by Americans) to be the best. I never found any added value in the PWE (based on ECMWF) or PWG (based on the GFS - just too coarse a grid to be any use), other than the "if they all agree, confidence is high" mentioned previously. Even worse is the PredictWind wave model - really not sure why they are bothering with that. I know and worked with the guys at the ECMWF WAM group and they are awesome. Hard to imagine what a few folk in a shed in New Zealand can add ...

The AROME French model is good if you are in its very limited area - the 1km model grid gives it some good insights close to shore.
UKMO not useless (though I think it's funny how often the UKMO YouTube output shows the ECMWF output, not theirs!), gives an alternative viewpoint

 

[B27]

I generally take the weather as it comes, trying to look ahead often doesn't help.
I do use Wetterzentrale.de, which gives access to the various soothsayers pictures.

 

[zoidberg]

In my experience, met forecasters have a rather better 'hit rate' when 'back-casting' - or explaining who got what, when and why, using database records.
Even then, they're far from reliable....

 

[geem]

I used the ECMWF reanalysis product professionally (I was a "science hippy", as Ze Frank calls us) and it's generally acknowledged (even by Americans) to be the best. I never found any added value in the PWE (based on ECMWF) or PWG (based on the GFS - just too coarse a grid to be any use), other than the "if they all agree, confidence is high" mentioned previously. Even worse is the PredictWind wave model - really not sure why they are bothering with that. I know and worked with the guys at the ECMWF WAM group and they are awesome. Hard to imagine what a few folk in a shed in New Zealand can add ...

The AROME French model is good if you are in its very limited area - the 1km model grid gives it some good insights close to shore.
UKMO not useless (though I think it's funny how often the UKMO YouTube output shows the ECMWF output, not theirs!), gives an alternative viewpoint

I have exactly the same view. Several hundred people working in the ECMWF model. Millions and millions invested in development. A shed in NZ turning out a "better" ECMWF and GFS? Who are they kidding. I have not met a proffessional weatherman who has any respect for Predictwind

 

[zoidberg]

'Storm in a teacup'.....

Now THIS is a storm:

Hurricane Milton ‘explodes’ into Category 5 storm as Florida braces for ‘life-threatening’ 180-mph winds: Live​

Some meteos are now quibbling about the Saffir-Simpson Scale and reckon it needs expansion to describe, for the first time, the 'Category 6 Hurricane'.
Milton ‘explodes’ into Category 5 hurricane as Florida braces for 180-mph winds: Live

 

[dunedin]

I have exactly the same view. Several hundred people working in the ECMWF model. Millions and millions invested in development. A shed in NZ turning out a "better" ECMWF and GFS? Who are they kidding. I have not met a proffessional weatherman who has any respect for Predictwind

Actually the few people in NZ seem to have an extremely good track record of doing better than much larger nations / organisations - in sailing and a number of other sports.
But in terms of “respect for PredictWind” there are at least two separate aspects
1) As the developer / publisher of an app platform for viewing and comparing a range of different weather models - that’s what I and many others use PredictWind for, and it is excellent
2) As a forecaster with their own model variants PWE & PWG - in my locality (which to be fair, is almost on the furthest opposite point of the globe from NZ) I do not find them useful. But they are free and optional so just don’t use them.

 

[geem]

Actually the few people in NZ seem to have an extremely good track record of doing better than much larger nations / organisations - in sailing and a number of other sports.
But in terms of “respect for PredictWind” there are at least two separate aspects
1) As the developer / publisher of an app platform for viewing and comparing a range of different weather models - that’s what I and many others use PredictWind for, and it is excellent
2) As a forecaster with their own model variants PWE & PWG - in my locality (which to be fair, is almost on the furthest opposite point of the globe from NZ) I do not find them useful. But they are free and optional so just don’t use them.

In my opinion, and experience, some sailors look at the PW app and plan a complex route that was accurate for a nano second until the next weather update. We know sailors that have got themselves into difficulty because they assume it's correct and because it's modern tech, it must be right.
I don't use it and can't see myself ever doing so

 

[dunedin]

In my opinion, and experience, some sailors look at the PW app and plan a complex route that was accurate for a nano second until the next weather update. We know sailors that have got themselves into difficulty because they assume it's correct and because it's modern tech, it must be right.
I don't use it and can't see myself ever doing so

Clearly if a muppet chooses to misuse a weather app they will do so. But that doesn’t make Predict Wind app a bad thing. Only the muppet misusing it.
So what pray do you think is a better source of weather information? Certainly from my perspective, using and comparing multiple weather models, as PW facilitates, is much better than relying on any single model.

 

[geem]

Clearly if a muppet chooses to misuse a weather app they will do so. But that doesn’t make Predict Wind app a bad thing. Only the muppet misusing it.
So what pray do you think is a better source of weather information? Certainly from my perspective, using and comparing multiple weather models, as PW facilitates, is much better than relying on any single model.

We use Windy proffessional. Most super yacht captains seem to use it. It's easy enough to do comparisons between models. The graphics are good. It gives us access to such things as Cape index that is useful when passsge planning in the Tropics.

 

[dunedin]

We use Windy proffessional. Most super yacht captains seem to use it. It's easy enough to do comparisons between models. The graphics are good. It gives us access to such things as Cape index that is useful when passsge planning in the Tropics.

But in my experience some sailors take a look at Windy and plan a complex route that is right for a nano second ……….
So you just prefer a different way to access basically the same models. That is fine, but don’t criticise other options for false reasons. (And super yacht captains probably have different needs and priorities from most leisure sailors - like which toys to get out for the guests.)

 

[geem]

But in my experience some sailors take a look at Windy and plan a complex route that is right for a nano second ……….
So you just prefer a different way to access basically the same models. That is fine, but don’t criticise other options for false reasons. (And super yacht captains probably have different needs and priorities from most leisure sailors - like which toys to get out for the guests.)

Er, no. Many Superyacht Captains sail across the pond to the summer spots in the Med for the summer, then back again to the Caribbean for the winter. It's a well trodden superyacht path of two Atlantic crossing every year. The Captains have more to worry about with 30 crew onboard than what toys a guest might want.
I and many others would much rather passage plan by comparing models and looking for weather stability rather than rely on a computer system that tells you it will be fine if you go this way on this particular day. Being active in understanding the weather and planning accordingly rather than letting the computer do it seem more prudent to me. We saw one guy leave the Azores a few years ago because PW said there was a favourable route. Nobody else agreed with him. He was back 4 days later with sails in tatters. He was an experienced sailor

 

[Ian_Edwards]

From my limited perspective, I use the UK met office model on predict wind. It has a 2km grid, and in costal water around NW Scotland, it uses the topography to give a good indication of way the winds bends around the mountains a funnels down the Glens.
For example, it predicts the acceleration zone in Loch Linnhe between Corran Ferry and Shuna Island when the wind has an easterly component, something the other models fail to do.
I don't find it very good on timing or predicting the wind strength. In September it consistently under estimated the wind strength, and was early on timing, but generally got the direction spot on.
But I also look at the other models on predict wind, along with the synoptic charts issued every 12hr. But 12hr is aong time when the weather pattern is unstable.