I never know how to date these things. When in doubt I add a day, just because it seems to me that storms arrive later than predicted (a week out) and often head out to see faster than predicted 24 hours in advance. I have no idea, I'm leaving it.
EDIT to add: Right now it looks like your date is right. Storm to start wet on the 18th turn white after that.
"You just need to go at that shit wide open, hang on, and own it." —Camp
So ur off to yer annual no shavin no bathin and all bullshittin n boozin session We call huntin camp !! Have fun , chill out and good luck altho i doubt you guys need it , you aint got one tied to a damn tree do ya ?
Life ain't a dress rehearsal: Spread enthusiasm , avoid negative nuts.