weather widget problem

First, visit System Preferences : Extensions panel. Select the Today category, and ensure that Weather is checked:

Close System Preferences. In the top-right corner of the menu bar, you will see the "hamburger" icon that when you click will open to a Today and Notifications panel. Select Today, and you will see a weather tool on it. Roll your mouse pointer over the top right corner of the weather tool and you will see an information ⓘ button. Click that. Notice the Celsius/Fahrenheit °C/°F letters. Click the one for your preference. Now, you can click the green add ( + ) button. Follow the instructions to enter your weather location, and press enter, then click "Done" in the upper-right corner of the tool.

Initially, you will see the location name, the weather avatar, and the temperature. If you click that panel, it will expand with more information. You click the "hamburger" icon again to hide the Today/Notifications panel.

Same problem for everyone, lots of reports that it no longer works, so maybe support has finally been pulled. Have you tried the weather item in the notifications panel.

There is always DarkSky from the web browser. The weather widget didn't work for me, and then it started working again without any intervention from me. It screen scraps Yahoo Weather, and that by itself may be a reliability issue.

That weather extension only resides in the Today/Notification panel. It is not a Dashboard widget. You would click the Today/Notification panel to open or close your view of the current weather. No need to leave it open, as that would be clutter.

For me, I am more interested in a three-day forecast, and approaching storms. I use a web browser for that information. Otherwise, a have a simple program that I wrote that I run from the Terminal command-line that scrapes Accuweather, and tells me the current real temperature, the felt temperature, and outside conditions (e.g. clear, T-storm, etc.).