Very nice images! This is a female Northern Black Widow (L. variolus). Given your location, the incomplete hourglass is a tell-tale sign for this species.

I just finished my first attempt at the guide page, and I haved selected some these images, because they clearly show what I was trying to describe. Thank you!

(I have also created guide pages for the Latrodectus genus, and for each species, with the species-specific characteristics to assist with identification of gender and species.)