Whenever I see a weather "app" I always think: "This is really a weather display utility" and then wonder about the quality / longevity of the service it depends on and how the information is provided.
What would interest me is an implementation that allows you to plug in different weather backends, so that having an API key to worldweatheronline, or screen-scraping weather underground, or building a bridge to your serial-port connected weather station all can target the same interface; to provide current conditions/historical conditions, a forecast, etc.
Are there standards for this, or is it mostly ad-hoc, the whim of the sites or commercial services which aggregate information and provide forecasts?
I've found they vary quite a bit, both in the data points they provide, and the depth of data. Especially comparing free vs paid services. Some provide historical data, others want lots of extra cash for that. Some provide hourly and even minutely results (like my current favorite -- forecast.io), and some do not. And the underlying conditions they provide can vary. You might get simply 'partly_cloudy' from one, an actual cloud cover percentage from another, or even the cloud cover at different altitudes from a yet another provider. So you'd have to do a lot of normalizing between providers to come up with a common API.
So it certainly could be done. And I actually looked into this a few years ago, but it wasn't trivial enough to make it worth the time back then.
I know very little about this space, but when you suggest screen scraping WU, are you implying that they have no API or XML feed or some kind of open feed of their data ?
That's disappointing. I always assumed they did ...
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Whenever I see a weather "app" I always think: "This is really a weather display utility" and then wonder about the quality / longevity of the service it depends on and how the information is provided.
What would interest me is an implementation that allows you to plug in different weather backends, so that having an API key to worldweatheronline, or screen-scraping weather underground, or building a bridge to your serial-port connected weather station all can target the same interface; to provide current conditions/historical conditions, a forecast, etc.
Are there standards for this, or is it mostly ad-hoc, the whim of the sites or commercial services which aggregate information and provide forecasts?
I've found they vary quite a bit, both in the data points they provide, and the depth of data. Especially comparing free vs paid services. Some provide historical data, others want lots of extra cash for that. Some provide hourly and even minutely results (like my current favorite -- forecast.io), and some do not. And the underlying conditions they provide can vary. You might get simply 'partly_cloudy' from one, an actual cloud cover percentage from another, or even the cloud cover at different altitudes from a yet another provider. So you'd have to do a lot of normalizing between providers to come up with a common API.
So it certainly could be done. And I actually looked into this a few years ago, but it wasn't trivial enough to make it worth the time back then.
http://graphical.weather.gov/xml/
Ex: http://forecast.weather.gov/MapClick.php?lat=37.76&lon=-122....
Unfortunately, as far as I know, the NOAA doesn't provide forecasts outside of the US and US territories.
It might... The wikipedia article for http://openweathermap.org/ (a commercial service) seems to point out they are using NOAA datas.
Thanks, this is pretty cool; I think the NWS qualifies as a stable source.
"or screen-scraping weather underground"
I know very little about this space, but when you suggest screen scraping WU, are you implying that they have no API or XML feed or some kind of open feed of their data ?
That's disappointing. I always assumed they did ...