City Hall staffers got an early wake-up call about Mayor Bill de Blasio’s chronic lateness.

Barely two weeks into de Blasio’s first term, aides launched a hunt for an alarm clock visible enough to get even the perennially tardy mayor moving, emails obtained by The Post reveal.

The search launched by mayoral aide Javon Coney on Jan. 14, 2014, came just three days after the nap-loving mayor ticked off graduates of the Department of Correction academy by showing up nearly an hour late to their ceremony and delaying the affair.

“Visible Clock For Mayor,” reads the subject line of the note sent by Coney to City Hall research coordinator Paula Sortino.