when make-up (often lady's) starts to run down their face due to a build-up of moisture, making an allusion to the wicked witch of the west more than appropriate.
'Man, it's pouring!! What a concert, I'm absolutely drenched. Gotta love outdoor shows! '..."No kidding! Look at the gal in front of ya - there's some SERious mascara melting going on."
by RowJ July 11, 2011
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