I am so sorry it has taken me so long to get back here to further comment, however, the widget has not had so much as a hiccup since my last install in May. I do want to thank everybody who tried to help me. And I still love Windy and I still miss having a radar widget, so if someone finds an app that has a radar widget for iOS, please pass the information my way. Please.
And again, thank you, all.
I get the same trouble as you, double labels on favorites which are also setup for alerts.
To avoid this, I suggest that you save these location/spots as Alert but not as Favorite
If you save them first as favorite and then set an alert for these favorites, you get the double labels.
So clean off your list of favorites, and save your surfspots as Alert in the small pop up when you click on the heart next to the search box.
Here is an example, where Bergen is a Favorite without setting up an alert, and a location at sea set as an Alert location. There is no double labelling
Maybe these two screenshots correspond to different reference time.
They were taken at 07:41, near to update time.
This problem remains till now?
For reference/update time:
Firefox 48 was released August 2016, while last release is 76.
Modern web apps are generally only compliant with most recent releases of most used web browsers (Chrome, Firefox and more recently Edge Chromium).
I don't know which web browsers and releases are supported by Windy, which uses many 3rd party Open Source frameworks...
I have just found the solution.
It has nothing to do with the cloud.
Those kind of settings are saved in the temporary memory of my PC.
In order to save my preferences, I had to click the settings,
and then "privacy and security".
In Firefox click the url "about:preferences#privacy".
Then I went to the cookies section and costumize it
so as not to delete the cookies and the temporary data for windy's website.