The brokerage cut its copper price forecast for the year by 5 percent to $3.59 per pound. It reduced the forecast for 2013 by 12 percent.
It lowered the forecast for zinc by 11 percent for this year and the next.
"Underlying our reduced metal price forecasts is the challenging macro environment in China, and deteriorating consumer sentiment and end-user demand," the brokerage said in a note to clients.
China's June trade data stoked anxiety about the strength of domestic demand in the world's second biggest economy as imports rose at only half the pace expected.
Raymond James also downgraded Lundin Mining Corp (Toronto:LUN.TO - News) to "market perform" from "outperform" and cut its price target on the stock by 50 Canadian cents to C$5.25.
The brokerage said it is waiting for a bounce in platinum and palladium as mine closures limit supply and help support prices.
Eastern Platinum Ltd (Toronto:ELR.TO - News), which produces platinum group metals such as platinum, palladium and rhodium, in May suspended funding for its Mareesburg mine and Kennedy's Vale concentrator plant in South Africa due to the operating environment in the country and the global slowdown.
(Reporting by Bhaswati Mukhopadhyay in Bangalore)