Brown-Forman's (BF.A, BF.B) revenue visibility is likely to be cloudy amid sluggish category trends in the US and developed markets, RBC Capital Markets said in a Q2 preview note Tuesday.

"While international growth (mainly emerging markets) should support the topline, we remain cautious on the overall topline outlook," the report said. The Q2 results are due Dec. 4.

Jack Daniels Blackberry is off to a strong start, but "category dynamics" are weighing on JD Black Label which is key for the topline to see sustained improvement, the report said.

RBC analysts said they expect the firm to reiterate its guidance for the year but are more comfortable at the lower end.

The analysts also said they are still not eager to step in due to a lack of visibility into near-term earnings power and US market softness despite a historically cheap valuation.

RBC kept its sector perform rating with a $30 price target.