I believe that's Typophone weather with a modified theme, but I could be wrong.
Get Typophone weather from Cydia
Then go to the Official App store and download Typophone Clock (or something)
It's a dollar, and it allows you to change the settings of Typohphone Weather without having to go to iFile and stuff, plus it has some other cool features like different themes, which I assume he's using.
That's just my opinion anyway. I quoted
my Typophone Weather lockscreen in one of the previous pages here with a custom wallpaper, but standard theme.
Anyway, you'll need to enable Typophone weather via Winterboard to actually use it as a lockscreen though