Windstorm disrupted US atomic clock sync by 4.8 microseconds last week

A severe windstorm in Colorado on December 17 caused a rare power failure at the National Institute of Standards and Technology (NIST) laboratory in Boulder, disrupting the synchronization of the US master atomic clock by 4.8 microseconds. While this tiny delay—less than five-millionths of a second—was imperceptible to the general public, it posed significant risks to high-precision sectors such as satellite navigation, telecommunications, finance, and power grid management, where even microsecond-level accuracy is critical. The NIST facility, which houses 16 ultra-precise atomic clocks using hydrogen masers and cesium beams, experienced a failure of both its primary power and backup generator, temporarily knocking offline the systems that synchronize and broadcast official time. To mitigate the issue, NIST advised users to switch to alternative time sources and employed “common-view time transfer” via GPS satellites to maintain synchronization through secondary clocks in Fort Collins. The outage was resolved after activating a secondary diesel generator, restoring backup