I think that hi viz colors like blue or red mixed with white will be better for the day time as mentioned above. I agree with hi vis like the yellow for night driving and gray, raining weather is good.
I did a experiment where someone used different colors and moved the colors passed my peripheral vision and out of green, orange, and the hi viz type yellow, I noticed the green, orange much more than the yellow. The yellow blended too much into the background. I didnt know when or what side the colors would move into my vision.