I'm using a threading library from agraham.
Actually what is going on is thee ICos weather library goes out and gets weather information when you set the city property. That can sometimes cause a delay, depending on your connection. This code is then reading the weather object and populating a global object with the current weather data.
I then wanted to notify all listeners (UI classes) that new weather information has appeared and let them update.
I just noticed the thread object has a Done event that I can use.