March 14 (Reuters) -U.S. cotton futures fell over 1% on Thursday, hitting their lowest levels in three weeks, as a stronger dollar and downbeat sentiment in the stock markets outweighed healthy U.S. weekly export sales figures.

* Cotton contract for May CTc1 fell 1.3 cent, or 1.4%, at 93.6 cents per lb by 12:45 p.m. ET (1645 GMT), having touched its weakest level since Feb. 22.

* The U.S. Department of Agriculture's (USDA) report showed net sales of 85,800 running bales for 2023/2024 were up 65% from the previous week, but down 10% from the prior 4-week average. EXP/COT

* "We could see some cotton acres begin to slip away back to soybeans as it just seems like there is no enthusiasm on the cotton side," said Jim Nunn, owner of Tennessee-based cotton brokerage Nunn Cotton.

* The cotton May contract is declining due to weakness in the stock market and a strengthening dollar, he added.

* The dollar index rose 0.5%, making U.S. cotton more expensive for overseas buyers.USD/

* Wall Street's main indexes slipped on Thursday as hotter-than-expected producer prices data likely muddied bets around the timing of the Federal Reserve's first rate cut..N

* CBOT soybeans Sv1 rose 0.2% to $11.99-1/4 a bushel. Soybeans and corn have recovered from three-year lows struck in the past month. GRA/

* Elsewhere, rains in Australia, Argentina and eastern Brazil this week are expected to slow cotton harvesting, weather forecaster Maxar wrote in a weekly note.

* Meanwhile, a U.S. government weather forecaster projects El Nino conditions will likely end by spring this year but saw a 62% chance that a weather pattern characterized by unusually cold temperatures in the Pacific Ocean, La Nina, will develop during June-August.

Reporting by Anushree Mukherjee in Bengaluru; Editing by Shailesh Kuber