[FFmpeg-user] Can I create an mp4 with dwell?

[Geoff Fox]

I'm a meteorologist making my own weather maps.  I use ffmpeg to create my
animations from still images, like this:
http://45.79.86.175/output/nam/sfc/conus-nam-slp.mp4

Typically:  ffmpeg -r 10 -f image2 -s 1920x1080 -start_number 02 -i
/var/www/html/output/hrrr/sfc/ord-hrrr-slp%02d.png -y -vframes 96 -vcodec
libx264 -crf 25  -pix_fmt yuv420p
/var/www/html/output/hrrr/sfc/ord-hrrr-slp.mp4

It would save me a lot of time if I could build a half second dwell for the
last frame.  Is this possible with ffmpeg?

Thanks for your help.