The mega-site, which is also the state's first drive-through site, opens at 8 a.m.
Also, starting today in New York City vaccines will be available at the Fort Washington Avenue Armory in Washington Heights.
The shots at all sites across New York are available by appointment for the 7 million New Yorkers who are in groups 1a and 1b, which includes seniors age 65 and older.
Governor Andrew Cuomo estimates it will take more than 5 months to vaccinate everyone in those groups.
RELATED: Where can you get a COVID-19 vaccine? Tracking availability and progress
Both openings come as New York sees more cases of the more contagious COVID-19 variant that was reported first in the United Kingdom.
There are now at least 15 confirmed cases statewide, located in two separate clusters.
The most recent cluster was identified Wednesday with two cases each in Suffolk and Nassau counties. A fifth case in Queens has also been linked.
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This cluster is unrelated to the previous cluster of cases in Saratoga Springs confirmed last week.
In light of this, New York City Mayor Bill de Blasio has called for flight restrictions to prevent more cases of that contagious strain from arriving here from the UK and other places.
The Jones Beach mega-site opens Thursday morning with a news conference, but the Nassau County executive was not expected to attend.
Laura Curran is quarantining at home after possible exposure to COVID-19. She is reportedly feeling well.
So far a little more than 700,000 people have received the vaccine statewide.
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Here are the most recent and upcoming vaccination site openings:
New York State vaccination sites:
State Fair Expo Center, Onondaga County
Westchester County Center
Jones Beach, Nassau County - Drive-Thru
Next week, more state sites open:
SUNY Stony Brook (LI)
SUNY Binghamton property in Johnson City
Dome Arena, Rochester
Plattsburgh Airport - Drive-thru
Utica Memorial Auditorium
U Buffalo South Campus
Aqueduct Race Track, Queens
CHECK THE LIST of who is eligible for a vaccine in New York State
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Tracking COVID-19 availability and progress in NYC
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