Looks like a Sonchus sp to me (on a cold day). but I don't know the
species in your area. if you cut the leaves usually there will be milky
sap, similar to lettuce.

I agree the colouration is not a defining characteristic, just a function of growing conditions. I'd say Sonchus too.

Agree that is Sonchus, which often turns color in the fall. I cropped your photo for a closer view, but could not see enough leaf detail to determine species. However, you can easily do that yourself. If the leaf base auricles are rounded, as shown in the first photo below, your plant is Sonchus asper. If the leaf base auricles are sagittate (2nd photo), your plant is Sonchus oleraceus.

Wow, thanks all!!! So, it's a sow thistle - with edible leaves, but invasive...