Switch weather widget to Celsius

Is it possible to switch the weather widget on the lock screen from Fahrenheit to Celsius?

I have tried everything I could imagine, switched Language Preferences between English and Russian, but it stays in Fahrenheit.

If you mean the default weather app it should be there
Click the hamburger menu → settings → common
And then its the first entry:

Maybe you also have to place the widget again after setting.

I have tried this one, but it only seems to affect the Weather app itself, not the lock screen widget.
How do I place the widget again?

In the widget view scroll down and click edit.
Then you can remove widgets.
And after that just place them again like you already did.

Edit: seems like weather app cant be removed.

But: the widget has its own setting, just click the “settings symbol” on the widget and you should get there:

I am talking about the lock screen (this)

and not this or that:

This is version 0.13, as I don’t have 0.14 for my Samsung Galaxy S4 mini yet.