The rain is really coming down now.
You are on the battlements, above the stables by the sound and smell of it. Below is the yard; to your left is the circular corner tower; to your right the square corner tower.
The massive keep stands before you. You can hear music and loud voices from inside - the celebration feast for Prince Aldun's forthcoming wedding - the revelery should be dying down soon, the prince seeking his chambers.
Most of the windows are too narrow to climb through.
To your left, beyond the square tower, there is a walkway from the walls to the keep.
On this side of the keep there is a circular tower with a balcony that stands proud from the keep about half way up. There is another, similar, tower on the other side of the keep. Both look like they might be solars or bedchambers. You
might be able to throw your rope and hook that far, but it looks a long way.
On the right side of the keep are the main gates. Probably guarded.
On the far side should be another walkway into the keep.
There should be some ground-level entrances around too - the kitchens, armoury, buttery, pantry, dungeon, etc. all need access after all. Somewhere within the walls there will also be a barracks, a smithy, and a granary or storeroom. The ground level and walls will likely be patrolled, even in the rain, and despite the storm lookouts will be posted in the towers to keep an eye out for ships on the horizon.
Overhead view: