If you were watching the Cathedral of Learning falconcam around 12:20pm today you saw Hope lay her fourth egg of 2018. I happened to be away from my computer so I missed it. Thank you to Jennifer, Debbie Key and Carol D. for letting me know.
If this is her last egg, then she probably began incubation yesterday. Add 32 days to yesterday's date and you'll get an approximate hatch date.
However, only Hope knows if she has a fifth egg coming. If she does, then she'll delay incubation and that will delay the hatch date.
Watch the Pitt peregrines here on the National Aviary's falconcam at the Univ of Pittsburgh.
(photo from the National Aviary snapshot camera at Univ. of Pittsburgh)