* Tesla soars in premarket after results, Wal-Mart falls
* Facebook to buy WhatsApp for $19 bln, shares fall
* Data from China weak, Ukraine turmoil continues
* Futures down: Dow 38 pts, S&P 3 pts, Nasdaq 14 pts
NEW YORK, Feb 20 (Reuters) - U.S. stock index futures fell on Thursday, pressured by weak results from Wal-Mart as well as global geopolitical and economic uncertainty that gave investors few reasons to buy despite a sharp selloff in the previous session.
* Some of Wall Street's biggest trading favorites will be in focus on Thursday, with Facebook Inc announcing a massive acquisition and Tesla Motors giving a strong earnings outlook.
* Turmoil in emerging markets continued, with Ukraine experiencing some of its worst violence since the end of the Cold War. The country's hryvnia currency dropped to near five-year lows, while the country's state debt insurance costs rose to their highest since December 2009.
* Emerging market growth was also in view after China's flash Markit/HSBC Purchasing Managers' Index fell to a seven-month low in February, falling under the level that represents expansion.
* Social networking giant Facebook said late Wednesday it would buy mobile-messaging startup WhatsApp for $16 billion in cash and stock, plus an additional $3 billion worth of restricted stock units to WhatsApp's founders. Shares fell 4.2 percent to $65.20 in heavy premarket trading.
* Tesla surged 10.2 percent to $213.35 a day after it reported fourth-quarter results that topped expectations and said deliveries of its luxury Model S electric sedan would surge more than 55 percent this year. If the premarket move holds, it would take the stock to an all-time high and build on its year-to-date advance of almost 29 percent.
* Wal-Mart Stores Inc fell 1.5 percent to $73.73 in premarket trading. The discount retailer reported a drop in U.S. same-store sales and gave an earnings outlook below expectations.
* S&P 500 futures fell 3 points and were below fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average futures slid 38 points and Nasdaq 100 futures lost 14 points.
* Stocks fell Wednesday after minutes from the January meeting of the Federal Reserve's policy-setting committee showed several policymakers wanted to hone in on the idea that their asset-purchase program would be trimmed in predictable, $10-billion steps unless there is a big economic surprise this year.
* While the statement didn't deviate much from previous Fed communications, market participants had expected the central bank to point to recent weakness in economic data and to reinforce its commitment to stimulating the economy.
* In the latest economic data, jobless claims fell less than expected in the latest week, while consumer prices rose 0.1 percent in January, as expected. Futures were little impacted by the data.
* Recent reads on the economy, including housing starts on Wednesday, have come in below expectations, with many citing poor weather for the weakness and some economists, including Goldman Sachs and Barclays, cutting their estimates for first-quarter growth.
* European shares fell 0.6 percent after France's service sector shrank by its most in nine months in February.