That sounds pretty good. Are you mentally prepared to start a 400k in the rain and continue on? How does riding in the rain effect your mood?

At least your temps are good. For the 300k last weekend, the forecast was 30's - 40's with rain and snow at sea level. It didn't rain or snow (whew!), but it was 30 - 40's all day. Cold and rainy can be borderline unsafe.

You've done this distance before, right?