Chance of rain %?

I am looking for a weather driver that supports chance of rain in %. I am not seeing this under most of the drivers. I would like to stay away fro, darksky as it wont be around after next year. Any ideas?

Most of the drivers are designed to only provide the information that the device or API they are for can provide. Chance of rain would have to be provided by the service for the driver to provide it.

Most of the weather services I checked while writing this answer base it on radar readings approaching the area in question. So this is something that home weather stations will not be able to do (unless someone has a doppler radar system installed...) themselves.

Weather Underground will do it as I use it myself.
However; unless you have a weather station which transmits data to them, they will not allow you access to their api


1 Like

I had a Weather Station years ago when i first stated home automation with Heyu. I need to look into getting a new one.

It doesn’t need to be an expensive one.
If you push ANY weather station data to WU then they will give you access to their api where you can get the forecast data.
(And I have a driver to get data from WU if you do)


1 Like

Is there any way to get the data available from Open Weather map. It looks like there isn't a chance of rain %, however there is a rain volume per 3 hours available.

I haven’t used open weather so I have no idea.
Is apixu still available?

Not anymore!

This does include it but isn't showing as attribute for me for some reason.

Probability of precipitation is an 'optional' attribute. Did you turn it on?

1 Like

Yeah I have it turned on and is in the data but still not in the attributes.

Are you sure it did a data poll after you turned it on? Mine is showing. PoP is also available in the 'threedayfcstTile' and the 'weatherSummary' attributes.

Yes but inst Dark sky going away soonish? Because of Apple? I think I might have an API Key for other reasons but I don't want to get on a solution that is already in sunset mode.

I would love to get more features in Open Weather map to include a rain forecast

If you do not already have an API Key, then I do not believe you can get one now. If you do have an API Key, they claim it will function until the end of 2021. That gives you up to 20 months to find an alternative solution.

Good luck to you.

I don't see rain forecast, either probability % or volume, available in the OWM API documentation.

EDIT ... I missed it. It does have rain volume (mm) for the last three hours in each three hour forecast.

Ultimately what I want is a morning notification to grab my rain jacket or umbrella on the way to work

My thoughts on this:

Disclaimer. Where I live we get 300+ days of sunshine a year, so rain is rarely an issue and welcomed when we get it.

There is not an 'obvious' solution even if all the forecast data is available. The 'daily' forecast is only available for paid accounts on OWM, so you are left with the 5day/3hour forecast (a forecast for every three hours for the next five days). You would have to determine your thresholds of how much accumulated rain over what time period would trigger your 'notification'? What if all that accumulation occurs in the very next three hours?, or the end of the day's three hour window?, or if is spread evenly over the entire day? How would that change your notification requirements?

It seems to me it would be a lot of work with subjective rules to construct an effective notification that in the end would be as insightful as just looking at this, that is available now.
image or

You should be able to build a RM to send a notification at your normal departure time if the PoP exceeds a threshold you specify.

I imagine not too far down the road there will be no more "open" weather sources. Sad...

As I am using a RGB indicator to tell me if there will be rain on my commute to or from work. With the three hour range I could simply Look at the two 3 hour units that effect my commute and make a notification based on if either of those two times meet the threshold to grab my umbrella or jacket.

This might actually be better than using the total PoP for the day. Even if this data was only pulled in for the current day or next 12 hours. It could be very useful

Your specific use case sounds reasonable. But others will have use cases that vary and will require other data elements from the API. So you should consider how to get and work with the data. You cannot just pull in 'the current day or next 12 hours'. You have to poll the API and take the results given, all of the results. For the 5day/3hour forecast that is about 30 data elements for each of the 40 time periods, or ~1,200 data elements per poll. You may only want two or three of those available time periods, but other users will require different time periods. Also consider that the 6 or 9 hour window you are interested in can be in different position depending on when the data was polled and when you look at it (e.g. If you wanted to look the night before). It get complicated very quickly.

I can be done. It will not be simple given the volume for data, but it can be done. You just have to build, or convince someone else to build, the driver to expose that data.

There is another thread that is looking at the NWS API as a replacement for Dark Sky. I am certain that someone will eventually share a driver to access free current and forecast weather data, hopefully before Dark Sky goes away completely. Good luck.