"Houston, you are beautiful," she wrote on Instagram.
A bumblebee emoji led some fans to speculate whether Beyonce will appear during Sunday's festivities.
Beyonce, a Houston native, performed during the halftime show during Super Bowl 50. The singer, whose fanbase calls themselves the "Bey Hive," is often associated with the bumblebee emoji. She announced that she is expecting twins with husband Jay Z on Wednesday, less than two hours before Gaga's post.