Doors and Windows - chaulking a higher heat area

I have a metal front door in which I've installed a new fan-light. The door faces south and there is a glass storm door in front of it. I made the mistake of using painters chaulk around the fan-light and it could not take the high heat generated by the sun through the glass on this south side of the house. What type of chaulk would be best to use? I need to be able to paint it as well. I noticed too on the old fan-light that it was "weeping" an oily film from the corners. I assumed it was the old chaulking breaking down. Any suggestions?

Silicone will take a fairly high heat...I use it to seal a metal frame around my fireplace opening for a set of doors 15 years ago and it's still there....seems I read 400 degrees on the tube when I used it.....

But you have another problem....if you used a plastic moulding around the fan lite glass, it probably won't last long, especially if the door is painted a dark color. I've seen them "droop" from the heat generated between a storm door and main door if they face south or west.....

And I thought I had enough problems already...the fan light does have plastic or plastic like trim and the steel door is brown. Hopefully the screw attachments will prevent drooping. For now, since it's up already I think I'll rechaulk as you've suggested, with the paintable silicone and hope for the best. If it droops in the future, I'll have to have a wood trim piece made. Thanks for the help, Tn...Andy.