This is a very small, and simple addon to manage Rime procs and Howling Blast. While Howling Blast has a cooldown, many Death Knights will /cancelaura Freezing Fog, so that casting Howling Blast will generate Runic Power. This addon provides a script function to take the place of that macro line, and will check to see if you have the runes to cast Howling Blast before canceling the Rime proc.

To use this addon, create a macro like this:
<<code>>

1. showtooltip /script ReasonRime() /cast Howling Blast <</code>>
   Or replace the occurrences of "/cancelaura Freezing Fog" with "/script ReasonRime()" in your existing macro.