Dreamweaver website to display almost live weather data.

This has almost nothing to do with Dreamweaver and everything to do with your skills as a coder or the system you connect your weather station to.   Look at https://openweathermap.org/stations-old

This is a good start 

https://developers.google.com/chart/interactive/docs/gallery/gauge

Well you would need to code it yourself which will be a mammoth task. Usually you would find an established weather api and bring back the data from that into your website.

Its possible to create your own if you have your own data by keeping all the information in a database then bringing that back to the website in the form of json formated data. Once you have the data in json format there are endless possibilities you can do with it. You can set a timer to regularly make a call to the database and update the information in 'real time' if you are changing the data every few minutes but I probably think the weather data will be good for  a few hours so not sure why it needs to be updated in 'real time' - you can just make a call to the database on page load when a visitor comes onto the website.

Building something like the above is only going to be possible if you have good coding knowledge, getting data from an established weather API is going to be much simpler.