"Investors continue to assess the risks posed by the U.S. Federal Reserve pulling back on its bond-buying program and taking liquidity out of the market," wrote Ishaq Siddiqi, a market strategist at ETX Capital.
U.S. stock futures were up 0.5%.
The threat of lower liquidity has left the markets feeling "uncomfortable," he said, leading to the latest spat of volatility.
U.S. stocks finished sharply lower Tuesday after a volatile day of trading, and markets are likely to remain on edge.
There is also limited corporate news or economic reports scheduled to move markets. Investors are waiting for the Treasury Department's monthly budget statement at 2 p.m. ET.
H & R Block ( and )Men's Wearhouse ( are scheduled to release quarterly results after the close. )
First Solar ( shares sank after the renewable energy firm announced plans late Tuesday for a new stock offering. )
European markets were drifting lower in morning trading. MSCI announced late Tuesday that it has reclassified the Greek stock market as part of its emerging markets group from its previous status as a developed market.
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|Overnight Avg Rate||Latest||Change||Last Week|
|30 yr fixed||4.29%||4.39%|
|15 yr fixed||3.35%||3.42%|
|30 yr refi||4.30%||4.40%|
|15 yr refi||3.33%||3.40%|
Today's featured rates: