Put your dancing shoes on for Hizzoner. (Roxanne Roberts/The Washington Post)

Hope I’m not ruining any surprises here, but planning is underway for Mayor Vincent C. Gray’s 70th birthday bash.

His chief of staff, Christopher Murphy, sent a note to Gray supporters early this morning asking them to set aside the evening of Nov. 13 for Hizzoner’s “Birthday Celebration and Constituent Services Fund Fundraiser,” to be held at Nationals Park. (Gray’s actual birthday is Nov. 8.)

Murphy also asked for volunteers to serve on the host committee, which typically means a significant financial commitment. “Don’t worry — it’s a light lift,” he wrote. “All we ask is that you share the forthcoming invitation with anyone you think would want to be included in the festivities.”

Mayoral birthdays are often a cause for celebration/fundraising. Gray held a similar event last year at B. Smith’s restaurant. Predecessor Adrian M. Fenty used his 38th and 39th birthdays to raise funds for his ill-fated reelection bid.

Nikita Stewart contributed to this report.