Water sometimes runs down the side jambs on two of our three west-facing sunporch storm windows. Lately it seems to be happening with every rain instead of infrequently. The gutters are clear and are draining properly. The water comes in around where the venetian blinds attach (see second photo).

During the summer, I tried spraying the windows with a garden hose, but no water leaked in. Maybe I didn’t spray long enough?

I’m thinking of running a bead of caulk above the drip cap on the vinyl siding (third photo). Any downside to that? Any other suggestions? Thanks in advance.

Jonathan