* Futures down: Dow 3 pts, S&P 2.75 pts, Nasdaq 7.25 pts
By Sweta Singh
March 3 (Reuters) - U.S. stock index futures were down for the second straight day since January on Friday, ahead of Federal Reserve Chair Janet Yellen's speech, which is expected to give further clarity on the possibility of an interest rate hike later this month.
* Yellen is set to speak at 1:00 p.m. ET (1800 GMT) at the Executives Club of Chicago. Her speech comes after several other Fed officials this week stoked market expectations for a March rate hike.
* Fed Vice Chairman Stanley Fischer, who has backed raising interest rates, is scheduled to give a keynote address on monetary policy in New York at 12:30 a.m. ET.
* Traders have priced in a 76 percent chance of a rate hike this month, compared with roughly 30 percent at the start of the week, according to Thomson Reuters data.
* U.S. stock markets closed down on Thursday as financials declined after surging a day earlier on increased expectations of a rate hike in March.
* Investors also await report from the Institute of Supply Management on its non-manufacturing index for February, which is expected to remain unchanged at 56.5. The data is expected at 10:00 a.m. ET (1500 GMT).
* The dollar index, which measures the greenback's strength against a basket of six major currencies, was poised for its fourth straight weekly gain, though it was about 0.1 percent lower on Friday.
* Among stocks, shares of Snap Inc (NYSE:SNAP) SNAP.N , which closed up more than 40 percent in their much-awaited market debut on Thursday, were up 1.3 percent at $24.80 premarket. World's largest advertising group WPP (LON:WPP)'s U.S.-listed shares were down 7.3 pct at $108.42 after it cut its 2017 net sales forecast. Firearm maker American Outdoor Brands' AOBC.O shares were down 7.5 percent at $17.93 after weaker-than-expected full-year forecast on Thursday. snapshot at 6:53 a.m. ET:
* Dow e-minis 1YMc1 were down 3 points, or 0.01 percent, with 26,777 contracts changing hands.
* S&P 500 e-minis ESc1 were down 2.75 points, or 0.12 percent, with 126,491 contracts traded.
* Nasdaq 100 e-minis NQc1 were down 7.25 points, or 0.14 percent, on volume of 22,299 contracts.