Play was called off by umpires Nigel Cowley and Billy Taylor at 18:00 BST.
A day-and-a-half has now been lost, play having been abandoned on Tuesday, when the rain arrived just in time to prevent Durham starting their second innings 170 runs adrift.
If play resumes on Thursday, Durham and Worcestershire will both have replacements playing.
Durham's Keaton Jennings and Worcestershire's Joe Clarke are now on England Lions duty, meaning call-ups for Michael Richardson and Tom Fell respectively.
Durham will delay a decision about their choice of captain for the forthcoming Twenty20 Blast until they discover whether Jennings, an England Test candidate, will be available to them.
No play was possible on day three of Durham's County Championship Division Two meeting with Worcestershire.