This falls under the category of "when it rains, it pours". A M7.9 earthquake struck today in the Tongan arc. It doesn't appear to be related to the Hunga Tonga Hunga Ha'apai eruption as it occurred a few hundred kilometers to the SSE of the volcano (remember folks, correlation does not mean causation). The earthquake looks like it was relatively shallow in the crust - ~10 km. All these events will definitely make life even more complicated for the people on Nuku'alofa (Tongatapu), but no word of damage/effects on the Tongan island. A tsunami advisory was also issued for Hawai'i and other spots around the Pacific Basin.

{Hat tip to my officemate Tatia for announcing the earthquake to us as it happened.}