checking the trichomes is the best way to know what stage your plant is at,my biggest concern when I used to grow outside was bud mold.with the damp mornings and short days it doesnt take long for mold to ruin your buds,its been damp and cold where im at and im south of you we had frost on tuesday and rain today and I would be worried if I had any growing out side,if your plant was in a pot you could bring it in at night or if you could try to cover it to keep it from getting the morning dew on it,it looks like its close. good luck and watch out for the mold