As the nuclear-weapons production complex begins a shift into overdrive, non-essential personnel at the Pantex site were asked to delay their arrival starting with Monday’s graveyard shift after a late-season ice storm moved in over the Texas panhandle.

Only a day after the spring equinox, the system dropped a wintery mix over Amarillo and the surrounding areas, prompting Pantex Plant operator consolidated nuclear security to delay the start of shifts for non-essentials by three hours, starting Monday night. The delay remained in effect on Tuesday morning, according to recordings on the company’s operations hotline and posts on Twitter.

There were also power outages at Pantex buildings 16-12, 16-19, 16-24, and the Firing Site, according to notices posted online.

Reported disruptions as of Tuesday morning were nowhere near as severe as those caused about a year ago by the deep freeze that crippled parts of Texas’ power grid and prompted Pantex — at the state government’s request — to rein in its power consumption for the sake of the rest of the grid.

Last year’s cold snap even damaged plumbing and piping at some of Pantex’s nuclear production facilities, a first for the plant,

Consolidated Nuclear Security said at the time.

This week’s foul weather passed through the panhandle with Pantex, like the rest of the National Nuclear Security Administration’s (NNSA) production complex, shifting into a higher gear to keep the nuclear-weapons agency’s series of five major nuke refurbs on schedule this decade.

According to someone familiar with the situation at Pantex, the plant was seeking to add graveyard shifts for more of its production departments, mirroring the surge at other NNSA sites including Kansas City National Security Campus in Missouri, which makes non-nuclear nuclear weapons parts, and the Los Alamos National Laboratory in New Mexico, which beginning around March switched over to 24-hour shifts at Technical Area 55, home of the expanding PF-4 Plutonium Facility that will host the site’s pit manufacturing plant.