Is it normal for my hair to turn different colors

My hair was black when I was born. Now it's black in the roots. It's mainly black and dark brown in the winter. It's dark brown/brown in fall. It's red and light brown in the spring. Now in the summer I get red/auburn and sometimes blonde hair in the very front by my widows peak!!!!!! I don't know if It's because I have Irish-Caucasian/Mexican/Indian/Hispanic,black blood but it's odd. I'm an African American girl and I'm more indoors unless I run track or walk my dogs or other various things etc. Is it normal for this to happen?