Weather retrieval is very important in order to plan our races. Of course the difference between the forecast and the actual conditions usually varies, but I think that this year I finally found the tool we needed: A statistical model of weather forecasts.
Most of the commercial tools are limited, for example software such as OpenCPN, Expedition and others are able to use the "standard" models such as GFS and more localized ones such as NAM. However they do not provide yet the option to fetch Ensemble models.
These models are using stochastic methods to estimate input variables based on observations and statistical distribution of their values. For example instead of using a single point wind speed let's say 15kn they use a probability distribution function to recalculate the model with different values for the same parameter.
By running all these simulations we can obtain:
- No a single forecast, but many based on the input assumptions of the model
- Average and mode values that are accounting for the variability in the measurements
So instead of using the GFS or NAM models that are going to tell me what the weather will be at a certain point we'll use the stochastic model that can give us variations of the weather at a certain point, this offers a more realistic view of what happen in the real world.
As most commercial tools cannot fetch this data, I had to develop my own service so that I'll be able to get these forecast before and during navigation. When I do not have what I need, there is always a solution :)
In order to do that it's quite simple, I have a command and control server running at home that I can query to retrieve the weather for a specific location and time frame. Then it sends me back only the data I need in order to save the amount of data transferred.
I've started doing that two years ago, once you start it's very easy to expand it to include other models!
If you're interested in weather routing, forecasts models and how to retrieve them do not hesitate to contact me.
Most of the commercial tools are limited, for example software such as OpenCPN, Expedition and others are able to use the "standard" models such as GFS and more localized ones such as NAM. However they do not provide yet the option to fetch Ensemble models.
These models are using stochastic methods to estimate input variables based on observations and statistical distribution of their values. For example instead of using a single point wind speed let's say 15kn they use a probability distribution function to recalculate the model with different values for the same parameter.
By running all these simulations we can obtain:
- No a single forecast, but many based on the input assumptions of the model
- Average and mode values that are accounting for the variability in the measurements
So instead of using the GFS or NAM models that are going to tell me what the weather will be at a certain point we'll use the stochastic model that can give us variations of the weather at a certain point, this offers a more realistic view of what happen in the real world.
As most commercial tools cannot fetch this data, I had to develop my own service so that I'll be able to get these forecast before and during navigation. When I do not have what I need, there is always a solution :)
In order to do that it's quite simple, I have a command and control server running at home that I can query to retrieve the weather for a specific location and time frame. Then it sends me back only the data I need in order to save the amount of data transferred.
I've started doing that two years ago, once you start it's very easy to expand it to include other models!
If you're interested in weather routing, forecasts models and how to retrieve them do not hesitate to contact me.
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