Is there a way to create an Image (AMI) when a spot instance receives a termination request?

Just before a spot instances gets terminated - I'd like to start creating an image of the instance.

I tested and AWS waits for image generation to complete before the shutdown completes.

I also saw this may provide easy access to termination information but have yet to see it on my instance:

wget -q -O - http://169.254.169.254/latest/meta-data/spot/termination-time