Feb 27 (Reuters) -U.S. cotton futures advanced on Tuesday, scaling their highest level in more than a year, on speculative buying and tight stocks.

* Cotton contract for May CTc2 rose 1.97 cents, or 2.1%, to 96.77 per lb by 10:46 a.m. ET (1546 GMT), the highest level since late-September 2022.

* "We see strong speculative buying in the market ... the grain market is sympathetically helping cotton stay aloft as well," Keith Brown, principal at cotton broker Keith Brown and Co, in Georgia, said, adding that the supply was dwindling in the United States.

* Seasonally, cotton prices tend to rise into the spring, Brown said.

* In the grains market, Chicago soybeans rose for a second session on Tuesday, recovering from a three-year low, as a reduced forecast of Brazil's ongoing harvest lent some support, though ample world supplies kept a lid on prices. GRA/

* The dollar index .DXY was subdued for the day. A weaker dollar makes the natural fiber less expensive for buyers holding other currencies. USD/

* Speculators raised net long position by 10,214 contracts to 67,851 contracts in ICE U.S. cotton futures in the week of Feb. 20, the Commodity Futures Trading Commission said on Friday.

* Elsewhere, Ivory Coast exported 255,644 tonnes of cotton from January to December 2023, down about 35.2% from the same period last year, provisional port data showed on Monday.

Reporting by Anushree Mukherjee in Bengaluru; Editing by Shilpi Majumdar