March 7 (Reuters) -U.S. cotton futures climbed over 4% on Thursday aided by robust weekly export sales data and a weaker dollar, while investors also awaited a federal monthly supply-demand report due this week.

* Cotton contract for May CTc1 rose 4 cents, or 4.2%, to 99.28 cents per lb by 12:29 p.m. ET (1729 GMT).

* The dollar index .DXY fell about 0.5%, its lowest since Jan. 24, making natural fiber less expensive for buyers overseas. USD/

* "We did have a good sales figure this week 330,000 bales, one of the larger ones we've had this year," said Jim Nunn, owner of Tennessee-based cotton brokerage Nunn Cotton.

* The U.S. Department of Agriculture (USDA) showed export sales of 330,800 running bales were up 24% from the previous week and 26% from the prior 4-week average.EXP/COT

* "You also had support from the grains and a weaker dollar," Nunn added.

* In the grain market, Chicago wheat rebounded from a 3-1/2 year low while corn and soybean futures also rose. GRA/

* The report also showed net sales of 52,000 running bales for 2023/2024 were up 30% from the previous week.

* "You could see a slightly lower number in India and possibly China, but you may see an increase in production in Australia and Brazil," Nunn said, referring to the USDA monthly World Supply and Demand Estimates (WASDE) report due on Friday.

* India's cotton production could fall 7.7% from a year ago to 29.41 million bales in 2023/24, the lowest since 2007/08, according to the Cotton Association of India.

Reporting by Anushree Mukherjee in Bengaluru;