I always expect these a little later in the year, probably due to the Hugos, but the 2018 Nebula Award winners have been announced:
https://nebulas.sfwa.org/award-year/2018/
I am surprised to find that I am familiar with 2 of these already. The best novel winner,
The Calculating Stars by Mary Robinette Kowal, is fantastic! As is the second book in the series,
The Fated Sky. Books 3 and 4 have not been published but DON'T let that stop you from reading the first two. The others are set in the same world but do not follow the same characters and (at least book 3) is parallel to the first two. Books 1 and 2 form at least a satisfying if not 100% complete arc by themselves.
I also have a copy of
The Only Harmless Great Thing by Brooke Bolander which was the winner of the Best Novellette. Those of you who follow the Tor.com book of the month giveaways should also have a copy.