I'd recommend using LockInfo at the moment.
You can rearrange the order of the plugins on the lock screen.
Open iPhone settings app in the usual way. Find LockInfo in the list of available settings apps (near the bottom in it's own section)
Open LockInfo settings
Click on Plugins in the LockInfo settings page
Click on Plugin Order
You can then tap and hold and drag up and down in the list.
The easiest way to get the LockInfo weather icons to appear where the temperatures are on the lock screen is to download an icon set from Cydia.
If you open cydia search and type WeatherIcon then you will see the icon themes. Glasklart WeatherIcon, Gruppled WeatherIcon etc
I use WeatherIcon - TICK.
This does install Winterboard (which is a theme management app for the iPhone). Once it's downloaded and resprung then you must go into Winterboard and just tap to select the weather icon theme you will now see in there. Don't do much more messing around in Winterboard as it can change the whole look and feel of your phone. After doing that you should have the weather at the top and the icons in there.
An alternative way to get the weather icons if you didn't want to install Winterboard involves connecting to your phone using SSH (which gives you access to the phones files and folders) and manually copying the icons into the correct folder.
I've posted how to manually get the weather icons here
Lock info Take a backup of you phone in iTunes before you start fiddling with SSH or installing winterboard