My only advice for the rainy guerilla grower is examine ever option you can think of to the fullest of getting a tarp over your plants during their flower cycle! Thin (but not too thin) plastic tarp with a suitable green or even hunter's camo colored mesh under it, securely attached, at a low enough level, could get you there. It has for me many times. I usually look for spots (I call a "grove" or "mini-grove", i dont know why, lol) which is just 4-6 trees (or even 10 or so thinner trees) to attach wire cables from and then link up the plastic and mesh underneath. if secured tightly it can hold up 40 mph winds and heaving rain/sleet in my experience while still letting airflow underneath and looking blind-ish, lol, from the sky.