WxSIM and Home Assistant

Has anyone used the forecasts generated by WxSIM to drive the weather forecasts in Home Assistant? I am interested in getting the software, but the primary interface for everything in our house is now Home Assistant - I pull the information from the weather station through Weather Display in to HA. I would like to use the forecast information to drive automations within HA, so it needs to integrate rather than just being a view from another web site.
Without that integration it is of little interest.


I haven’t seen an integration yet but it’s something I’m interested in too. I’ve not done anything about it yet but I did wonder whether there was a way to put the data into MQTT so that it could be read out by the existing MQTT integration.

I have not figured it out yet, but I have been thinking / wanting the same thing!

I’ve been doing some investigation into this today. I have a few integrations installed that handle forecast data - OpenWeatherMap and Met.No (two versions - daily and 6 hours). Having looked at how these work in a bit more detail I’ve realised that I’m not sure exactly yet what I want to achieve! Other than displaying the data on some dashboards I’ve not tried to use them in any other way yet.

OpenWeatherMap - Reads (for a free account) 3 hourly forecast data (and current conditions) from OWM into HA. Whilst it loads (can load?) 5 days worth of forecast data there isn’t a way (that I’ve found yet) to see the future forecast values. It presents the forecast data as a series of entities for the current hour. So you can ‘use’ the current forecast temerature for the next hour, e.g. to set your heating level in advance of any forecast temperature changes. This type of forecast is obviously useful for controlling your environment, but doesn’t appear to be useful beyond the current hour.

Met.No - I have two integrations of this installed. Both download some current conditions. One also downloads 6 days of daily temperature forecasts and 24 hours of 1 hourly forecasts. With this integration I only seem to be able to display cloud conditions and min/max temperatures (daily) or cloud conditions and hourly temperature values.

The second integration downloads 9 days of 6 hourly forecasts. I can display cloud, temperature, wind speed/dir and precipitation amount/probability.

With both Met.No integrations I can’t see a way to access the forecast data for smart control purposes.

So the OpenWeatherMap integration seems to be more about using forecast data for control purposes without being able to display it and Met.No seems to be the opposite, i.e. providing a forecast display without being able to use the data to control anything.

Having now, hopefully correctly, understood this I’m left wondering what I really want to use forecasts for. I think it’s probaby both purposes…people want to see what the weather is going to be like for the near future and I think I want to control the heating using forecasts too. So any WxSim integration is probably going to have to be able to achieve both of these functions.

  1. Does this make sense with what others are seeing/have seen?
  2. What are you hoping to use WxSim forecast data for in HA?

I have a lot of weather integrations installed - Tomorrow.io, Pirate, Open Weather Map, Accuweather, plus met.no (which I think is the default).
What I am primarily looking at is the forecast on the dashboard, plus early warnings of things like rain and probably temperature.
Something I was playing with in the summer was to try and use the predicted outside temperature to cool down the house using air conditioning earlier when the electric was cheaper.
What I was hoping for was a replacement for the tomorrow.io nowcast - which I have set to cover the next 3-6 hours.
The other use is to try and see at a glance whether the local forecast is any better than the ones coming from the main players. I have a weather page on HA, which has most of the information coming off the weather station, plus rain radar and next few hours and next few day forecasts, and it would be good to have the local version of that to see whether there is a major difference.
At a bare minimum, having that data available to the weather cards would be a good start and move on from that.

I have now started to work on trying to get WXSIM output forecast in to Home Assistant.
So far, with the aid of ChatGPT, I have managed to convert latest.csv in to a JSON feed in real time.
I am now in communication with Tom to work out exactly what all of the acronyms and other data are so that I can get the data in to HA. Most likely this will be via a long REST YAML file rather than a fancy integration - at least to begin with.