Do you have the Home Assistant websocket node installed in Node-Red?
You could poll UDP thru Node-Red directly but I would recommend the HA addon to Node-Red, which in turn will also allow you to perform automations via Node-Red.
Here is my work in progress for current conditions flow in Node-Red, on example in it is determining if it Windy. It is specifically setup for my setup but you should be able to get an insight. You can copy the below and ‘import’ it into Node-Red. Nevermind…it is too big to post here. I will create a simple example later.
