SAO PAULO, Feb 2 (Reuters) - Agribusiness consultancies Cogo and Datagro on Wednesday slashed their forecasts for Brazil's 2021/22 soybean production, joining a series of private firms that cut their estimates earlier in the week as bad weather affects the crop outlook.

Cogo said it now sees oilseed output reaching 125 million tonnes, down from a previous forecast of 131 million tonnes and 14.2% below its initial projection for this season.

Cogo's managing partner Carlos Cogo said in a report sent to Reuters that further downward revisions are not ruled out yet.

Datagro estimated Brazil's soybean crop at 130 million tonnes, versus 142.05 million in its December projection and 144.06 million tonnes initially forecast for 2021/22, citing weather problems caused by the La Nina weather pattern.

Flavio Roberto de Franca Junior, Datagro's head of grains, said in a statement that the new forecast comes as rainfall levels dropped in Brazil's three southernmost states, as well in western Sao Paulo and southern Mato Grosso do Sul states, from November.

Datagro said the drought's impact on production would have been larger if planted area had not grown 3.7% year-on-year to 40.51 million hectares (100.1 million acres).

Cogo's and Datagro's new forecasts come as private consultancies AgRural, AgResource and StoneX also trimmed their output estimates earlier in the week. They all see Brazil's soybean crop now falling short of the 130 million-tonne threshold.

Brazil's food supply and statistics agency Conab is expected to release its new official forecast on Feb. 10.

(Reporting by Roberto Samora and Nayara Figueiredo; Writing by Gabriel Araujo Editing by Marguerita Choy)