Thanks everyone. I'll probably go with 12-month Discover CD's at 2.5% interest since we already have our savings and CD accounts there. I don't think they allow partial withdrawals.
This will be for my mom's savings. She's in assisted living and she'll probably burn through her money in 8 years at the current rate so she can't tolerate any risk to her savings. We already had to tap into her current CD with a hefty penalty before we sold her house. Her current CD will mature in two days, so I'm looking to minimize the penalties with future CD's in case we need to tap into the money again. With proper planning we shouldn't need to, but emergencies happen, especially in her situation. I'll still keep a sizeable chunk in regular savings so she can get to it if she needs to.