Woods has withdrawn from next week's Genesis Open -- a tournament that benefits his foundation -- and the Honda Classic in Florida.
The former world No. 1 blamed a recurrence of the back spasms that forced him to retire from last week's Dubai Desert Classic.
"My doctors have advised me not to play the next two weeks, to continue my treatment and to let my back calm down," Woods, now ranked 674th, said in a statement on his website.
"This is not what I was hoping for or expecting. I am extremely disappointed to miss the Genesis Open and the Honda Classic."
Woods is still expected to travel to Los Angeles to support the Genesis Open and his foundation, while a decision on his playing schedule will be determined after further injury assessments.
It is 20 years since Woods won his breakthrough major at the Masters, but his presence at Augusta in April now looks in doubt.
"Never feel great again"
The Dubai tournament was Woods' second full-field event since returning from a 15-month injury layoff following multiple back surgeries.
Before the event he admitted that a catalogue of injuries during his career had taken their toll on his body.
"I feel good, not great. I don't think I will ever feel great because it's three back surgeries, four knee operations," Woods told former R&A chief executive Peter Dawson in a video interview for Dubai's Vision Magazine at the Burj Al Arab hotel.
"I'm always going to be a little bit sore. As long as I can function, I'm fine with that."
Woods said he experienced "dark times" during his lengthy layoff and doubted whether he would ever play the game again.
"It was a tough, tough road," he told CNN's Living Golf show. "There was a lot of dark times where I couldn't get out of bed, couldn't move, the pain was too great.
"Anyone who's ever had nerve pain in their back, they certainly understand what that feels like. I honestly didn't know this time last year, I didn't know if I'd ever play golf again. Just because of the fact that it's nerve pain."
Woods made his comeback in a limited field event in the Bahamas in December and showed promise by leading the field in birdies, although a number of costly errors meant he finished 15th of the 17-man field.
He missed the cut in his next event, the PGA Tour's Farmers Insurance Open at Torrey Pines in California last month and slumped to a five-over 77 on day one in Dubai before retiring.
Woods looked to be moving gingerly around the Emirates Golf Club course, but told reporters afterwards he "wasn't in pain at all," adding: "I was just trying to hit shots, and I wasn't doing a very good job."
Woods hasn't won a tournament since 2013 and clinched the last of his 14 majors in 2008.
The Masters starts on April 6 in Augusta, Georgia.