NIST maintains several time standards. Gaithersburg MD is still up and I assume Hawaii is as well. Other than potential damage to equipment from loss of power (turbo molecular vacuum pumps and oil diffusion pumps might end up failing in interesting ways if not shut down properly) it will just take some time for the clocks to be recalibrated against the other NIST standards.

Gaithersburg went down on December 8th, is there confirmation that it's fully functional again?