It is a tough, tough question. We wait all year for this and it goes by quickly. Many of us get a mere handfull of days in the stand as it is. A deer that gets a razor sharp arrow through the pump station is going to die within a short walk from your stand.
ON THE OTHER HAND, bow hunting is a game of inches and so much of what happens is beyond our control. I have had well hit deer travel over 100 yards. Any brush pile can hide a big animal from view. A steady rain does not make a blood trail harder to follow, it destroys it! It is wrong to shoot a deer with anything but high percentage shots with a high percentage chance of a quick recovery.
My personal choice is this. I will hunt in a light drizzel or under the threat of a passing shower. Under these conditions my shot selection becomes extreemly limited. I will remain on stand during a rain shower, but I will hang my bow up and watch. I will not even bother to go out if the forecast (which I watch like a hawk) calls for sustained rain.
