Slips and tire chirps accelerating on right turns

My 2004 just started something I can't figure out. From a stop, making a right turn, accelerating normally, it hesitates/slips? and sometimes the tire chirps. And of course, it does not happen every time, road conditions vary, no clear connection to anything else. And the "Maintenance Required" light just came on, but the slipping has been happening for a month or more. Only 32,000 miles, got a steal from my father-in-law, but I've only had it 3 months.

Thanks in advance, I've already found other answers on this forum that have helped a bunch.

Billdig
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2002 Prius
2004 Prius
(that would be two "Prii" right?!)

 

Actually, I'm in Colorado and have not changed out the winter tires. Should have by now, but it did snow just last week. I'll wait until I change back the the all season radials before assessing if there's a problem.