Predict wind app.

greeny

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Normally I've been using Windytv as a weather app but i've just downloaded Predict wind. On PC and on Android.
You guys are probably going to tell me that you've been using it for years.
But one apparently new feature is the ability to switch screen map to its new ais mode. This means not having to open other apps to see ais data.
I'm well aware of the shortcomings of internet based ais systems but it is useful when sat at house, away from the boat system, to see and identify vessels out in the river as they come and go.
 
It would be more useful if they could also allow a connection to the boats wi-fi to take the ais feed from the on-board systems so you have a repeater to use in the cockpit?
Apart from OpenCPN I have yet to see a decent AIS implementation for a smartphone with intelligent real time CPA vectors etc.
 
It would be more useful if they could also allow a connection to the boats wi-fi to take the ais feed from the on-board systems so you have a repeater to use in the cockpit?
Apart from OpenCPN I have yet to see a decent AIS implementation for a smartphone with intelligent real time CPA vectors etc.
We use a Yakker. Squirts AIS around the boat as WiFi to be picked up on phone or tablet with Navionics. Works well.
 
missed that, Ta.

Though prefer marinetraffic , easier to check where your cruising mates have got to. But limited to 6 vessels with the free tier.

Don't rate predictwind's own models at all, day or 2 out waste of time, why bother.

Though useful website to watch how the models pan out >

WPHoqon.jpg
 
We use a Yakker. Squirts AIS around the boat as WiFi to be picked up on phone or tablet with Navionics. Works well.
I have a Quark A031 which does the same. Question was more about an App which showed graphically CPA vectors automatically and the Open CPN software also shows if you will pass ahead of behind a vessel. It would be nice to have a simple App to show similar AIS data, CPA etc without all the additional navigation that Open CPN offers.
 
missed that, Ta.

Though prefer marinetraffic , easier to check where your cruising mates have got to. But limited to 6 vessels with the free tier.

Don't rate predictwind's own models at all, day or 2 out waste of time, why bother.

Though useful website to watch how the models pan out >

WPHoqon.jpg
Do make sure you look at the validation page (lower left on menus). It gives details on the most accurate of the data being used. I've taken to looking at the AROME data for next couple of days wind strength and direction. While I was away sailing for the summer, it was generally the most accurate although quite often PWE was near or at the top.
 
Do make sure you look at the validation page (lower left on menus). It gives details on the most accurate of the data being used. I've taken to looking at the AROME data for next couple of days wind strength and direction. While I was away sailing for the summer, it was generally the most accurate although quite often PWE was near or at the top.
I tried it by logging actual calibrated airport wind against predicted , which is a load of work , 2 days out PWE / PWG models usually went way out after couple days. Might be better now but why bother anyway, they're just fiddled with gfs/ecmwf data, nothing is added.
The double page view is nice though.
Windy compare is better to check what the different models are putting out. imho. Nice plus for windy is the altitude option so you can see the upper warm air masses in a front, fascinating stuff watching the polar front evolving as the polar / ferrel air masses jostle each other. ?
 
Some comments.

1. All models have built in smoothing/filtering of output so that effective resolution is about 5 grid lengths. Bear in mind when reading claims about precision of forecasts.
2. PW uses ECMWF and GFS data but only on a 0.5 degree (50 km) grid as opposed to 0.1 degree and 0.125 degree. Draw your own conclusions.
3. AROME is based on output from Meteo France ARPEGE. On WMO/ECMWF objective verifications this model is less good than ECMWF, U.K. UM, GFS.
4. Small weather details have short lifetimes.weather systems move. Hence, beyond a few hours detailed models are, effectively, little more than the global models on which they are based.
5. Detailed models run by national weather services use detailed data input, including radar imagery. Looking at the Met Office radar app, it is clear that they can still fail to predict small detail very well.
6. Detailed models run by anyone else, including PW, do not, as far as I know, use detailed data. They simply interpolate from the global model. In the case of PW, they interpolate from a 50 km grid. Draw your own conclusions as to the difference between any “unofficial” detailed model and one run by national weather services.

On a practical cruising man’s observations on our summer in France this year, I was using GFS, ICON and ECMWF. For the first 2 or 3 days there was little to choose. We used GFS and ICON for the first 24-48 hours. ECMWF was not available via Windy, Ventusky, Saildocs until well over 2 hours later. For planning purposes, we used, primarily, ECMWF. We looked for consistency between successive model runs and were happiest when the GFS was similar to ECMWF.

Added later - Adlard Coles Skippers Cockpit Weather Guide says it all.modesty forbids that I should mention the author?.
 
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Some comments.

1. All models have built in smoothing/filtering of output so that effective resolution is about 5 grid lengths. Bear in mind when reading claims about precision of forecasts.
2. PW uses ECMWF and GFS data but only on a 0.5 degree (50 km) grid as opposed to 0.1 degree and 0.125 degree. Draw your own conclusions.
3. AROME is based on output from Meteo France ARPEGE. On WMO/ECMWF objective verifications this model is less good than ECMWF, U.K. UM, GFS.
4. Small weather details have short lifetimes.weather systems move. Hence, beyond a few hours detailed models are, effectively, little more than the global models on which they are based.
5. Detailed models run by national weather services use detailed data input, including radar imagery. Looking at the Met Office radar app, it is clear that they can still fail to predict small detail very well.
6. Detailed models run by anyone else, including PW, do not, as far as I know, use detailed data. They simply interpolate from the global model. In the case of PW, they interpolate from a 50 km grid. Draw your own conclusions as to the difference between any “unofficial” detailed model and one run by national weather services.

On a practical cruising man’s observations on our summer in France this year, I was using GFS, ICON and ECMWF. For the first 2 or 3 days there was little to choose. We used GFS and ICON for the first 24-48 hours. ECMWF was not available via Windy, Ventusky, Saildocs until well over 2 hours later. For planning purposes, we used, primarily, ECMWF. We looked for consistency between successive model runs and were happiest when the GFS was similar to ECMWF.

Added later - Adlard Coles Skippers Cockpit Weather Guide says it all.modesty forbids that I should mention the author?.
I have always thought that PW fiddling with recognised models a joke. What do they think they can do that the huge budget well resourced international weather organisations can't?
 
It would be more useful if they could also allow a connection to the boats wi-fi to take the ais feed from the on-board systems so you have a repeater to use in the cockpit?
Apart from OpenCPN I have yet to see a decent AIS implementation for a smartphone with intelligent real time CPA vectors etc.
291564137_10224849857327194_2652888486210074485_n.jpg
293063820_10224904592735545_1466896126914924170_n.jpg

Imray Navigator is perfect!
 
The OpenCPN screen shows graphically the CPA points - in the attached example I will pass astern of the ship Al Khor. It shows the heading on my boat as well as the COG to provide a pretty accurate prediction. It is sometimes quite nice to see the actual CPA and to know if you will pass astern or not. I was wondering if there was a less hardware intensive software that would run on Android phones of whether to stay with the OpenCPN.
I do have AIS on my old C80 plotter at the chart table, but when short handed I am really after something as a potential alternative to OpenCPN and that is easy to use in the cockpit without having to tap on a screen to interrogate AIS targets to determine CPA etc.
Screenshot_20210701-135404_OpenCPN.jpg
 
The OpenCPN screen shows graphically the CPA points - in the attached example I will pass astern of the ship Al Khor. It shows the heading on my boat as well as the COG to provide a pretty accurate prediction. It is sometimes quite nice to see the actual CPA and to know if you will pass astern or not. I was wondering if there was a less hardware intensive software that would run on Android phones of whether to stay with the OpenCPN.
I do have AIS on my old C80 plotter at the chart table, but when short handed I am really after something as a potential alternative to OpenCPN and that is easy to use in the cockpit without having to tap on a screen to interrogate AIS targets to determine CPA etc.
View attachment 142765
Yet to see a better graphical ais view to opencpn anywhere, but the android version isn't too hard on resources, bit cramped on the screen though. Cheap tablet might be an idea if the budget is there. On a tablet I used to use navionics most of the time but with opencpn running as well so easy to flip to see ais targets.
 
The OpenCPN screen shows graphically the CPA points - in the attached example I will pass astern of the ship Al Khor. It shows the heading on my boat as well as the COG to provide a pretty accurate prediction. It is sometimes quite nice to see the actual CPA and to know if you will pass astern or not. I was wondering if there was a less hardware intensive software that would run on Android phones of whether to stay with the OpenCPN.
I do have AIS on my old C80 plotter at the chart table, but when short handed I am really after something as a potential alternative to OpenCPN and that is easy to use in the cockpit without having to tap on a screen to interrogate AIS targets to determine CPA etc.
View attachment 142765
If you look at my second picture you can see the same on the Imray app except no heading line. Plus these little graphic boxes if you tap on a contact. Handy to have MMSI for DSC calls.
Screenshot 2022-09-11 at 12.40.58.jpg
 
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You guys are probably going to tell me that you've been using it for years.
But one apparently new feature is the ability to switch screen map to its new ais mode. This means not having to open other apps to see ais data.
I'm well aware of the shortcomings of internet based ais systems but it is useful when sat at house, away from the boat system, to see and identify vessels out in the river as they come and go.
If I understand this correctly you are looking at weather and it wants to display AIS data. Sounds like an answer looking for a question.

Perhaps I do things differently, but plan passages including looking at weather before I set off. AIS data is useful on passage.

Having spend a night in fog between Cabo Finisterre and A Coruna it was useful to look up a ship that was 2 NM off our bow and 'wandering about' on radar as a vessel underway, but not making way.
 
If I understand this correctly you are looking at weather and it wants to display AIS data. You understand incorrectly - I don't think I said that.
Sounds like an answer looking for a question. Really don't understand your point.

Perhaps I do things differently, but plan passages including looking at weather before I set off. AIS data is useful on passage. So do I. I'm not using it for passage planning. Quote "I'm well aware of the shortcomings of internet based ais systems but it is useful when sat at house, away from the boat system, to see and identify vessels out in the river as they come and go."

Having spend a night in fog between Cabo Finisterre and A Coruna it was useful to look up a ship that was 2 NM off our bow and 'wandering about' on radar as a vessel underway, but not making way. So maybe it was useful then?

I posted this as a bit of "useful or not" information that others may not have noticed had changed. It generated quite a bit of interesting discussion albeit not directly about Predict wind app.
 
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