LDS Church in Harlem
Yes there is an LDS church located in the Morningside Heights area, and more specifically located at 368 Malcolm X Blvd, New York, NY 10027. There is a Young Single Adult Ward which is flowing with single adults from all over the world plus two family wards, one being a Spanish ward. For more information regarding times and events this Church's website is http://www.harlemonestop.com/organization/511/the-church-of-jesus-christ-of-latter-day-saints-harlem-1st-ward.
I was lucky enough to attend sacrament meeting at both the Young Single Adult Ward and the Spanish Harlem ward. The YSA ward was literally overflowing with young adults to what seemed to be from all over the world. I don't know about you but as I have grown up in Utah it has always been so fun to go to church out of the state and meet people who are old and new to the church from all over the world that are within my age limit. Did you serve a Spanish speaking mission and want to brush up on a place to practice? Well the Spanish Harlem ward is the place to be. I personally did not, but I took the opportunity anyway to attend. Although I knew very little to no Spanish I felt the need to test out the waters in Harlem. To all others who wish to branch out and don't know much Spanish there is no need to worry! The people are very friendly and there is always someone there translating the message of the speakers through available headphones. I personally felt that the testimonies that were shared were very touching, the spirit was strong and It was easy to see the strength and love for the gospel that some of the members of the ward had.