Does flash.now work in Ruby on Rails 3+?

Currently I am on Rails 3.0.3 and I am trying to render a 'new' action in my user controller but when I get an error I get the initial flash on the new user page, but also get a repeat of the flash message when I go to another page.

From the research I've done, you use flash.now[:notice] for renders but it isn't working. Its not clearing the flash after showing it.

Here is my code:
users_controller.rb

def create
   flash.now[:notice] = "flash test."
   render :new
 end
 

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