That Meyer is ripe; pick it and enjoy it. You can leave it on the tree, if you wish until February; it will get more yellow, but not better. Meyers are one of the few citrus that will not fall off the tree when mature.

You say that it is ripe, but only the half facing the sun is yellow. The other side is more green, but the yellow is spreading to the other side. Does the fruit have to be fully yellow to be ripe? Or like you said, is it ripe right now even though it is still somewhat green on one side?

Thanks for the help John

It is ripe now. Cut one and you will see. From this point onward, it may get more yellow; but it will not get better. In fact the lemon is yellow now; to make it more yellow only requires the degradation of the chlorophyll that is hiding the yellow; in the industry that is called de-greening; and that is commonly done with ethylene gas or a liquid ethephon (liquid ethylene) bath. You can also simply put them in a cool dark place for 15 days... if you put a board on your lawn for 15 days, the grass under it will be white (the chlorophyll has been degraded); and that, my friends is your biology lesson for the day... I didn't learn it in school; I learned it from years of experience.

Thanks a lot!