This year’s Diner en Blanc could have a special uninvited guest: Rain.

The annual outdoor picnic, for which 4,300 tickets priced at $39 apiece sold out in a manner of hours, will absolutely go on. (Oh, and you’ve got to bring your own food, your own table, your own chairs and your own setting; all the ticket gets you is access to the location, which is a secret until right before the event.)

As you might imagine, Philadelphians are conflicted about this event. Anyway, if you’ve already bought your tickets, you’ve been warned: “Guests should be prepared to attend the event rain or shine.”

Meanwhile, according to the National Weather Service, here’s the current forecast for Thursday, and Thursday evening: Anywhere from a 50 to 70 percent chance of rain, regular and/or heavy.

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So what’s a DEB, uh, diner to do? We reached out to the local organizers, and their advice boils down to this: Bring an umbrella, but maybe skip anything bigger.

“We recommend people bring white or clear umbrellas and/or ponchos. They can bring a tent if they wish but the umbrella and poncho option is much more mobile – as a tent would be hard to transport with other items,” the organizer said. “We don’t encourage the tent however as that could also take up a lot of space.”

Remember, Diner en Blanc happens around the world; while it started in Paris, there have been events held everywhere from Toronto to South Africa, both sites which have seen rain, the organizer noted. But either way, our source notes, “fingers crossed it passes!”

Chris Krewson is the executive director of LION Publishers, a national nonprofit association that serves local journalism entrepreneurs build sustainable news organizations, and the founding editor of...