PHILADELPHIA — My mother, Fran, is not a great one for selfies. But a few weeks ago, I was scrolling through my Facebook feed and saw a new shot of my mom, grim of face and wet of hair, wrapped in a silvery warming blanket, in front of a row full of gym lockers. “Had to take refuge outside from pool during call-in threat that caused J.C.C. evacuation,” she’d written. “Pool and nursery school evacuated.”

I went to my Facebook page to share Fran’s post and asked if anyone had more information.

People did, but not just from Connecticut, where my mom was swimming at the Jewish community center in West Hartford.

“Second time in two weeks down here at the J.C.C. in Delaware. My kids go to the preschool and have been evacuated both times,” one friend wrote. Another said: “I just got an alert that the J.C.C. in Marin, Calif., was evacuated due to a threat. The hate seems to be spreading like wildfire.” And another: “At 11:45 they evacuated our J.C.C. in West Bloomfield, Mich. I live directly across the street, and all seems quiet there.”

On the day my mom was forced to get out of the pool, Jan. 18, 26 J.C.C.s in 17 states were the targets of bomb threats. Even if my mom hadn’t posted her wet-faced selfie, it would have felt personal.