U.S. and European markets are notably weak today following a strong sell-off in Asia. As a result of today’s sell-off, most major indices around the world have shed their August gains.

China’s Shanghai Composite plunged 5.8% on continued worries over economic weakness and tighter bank lending during the second half of the year. It was the worst day for China’s benchmark index since November 18. Although it is still up 58% this year, the index is at its lowest level since the middle of June, and has now dropped 17% since closing at a 52-week high on August 4.

Here are some of the hefty declines of the major China ADRs since they closed at highs earlier this month:

• LDK Solar (LDK)  -22%
• Suntech Power (STP)  -19%
• Aluminum Corp of China (ACH) -15%
• PetroChina (PTR) -11%
• China Petroleum & Chemical (SNP)  -10%
• CNOOC (CEO) -10%
• China Mobile (CHL)  -9%  

The rest of Asia was very weak too, and with the major Asian indices now at their lowest levels of the month. Despite exiting its longest recession since World War II, Japan posted slightly weaker-than-expected Q2 GDP growth (+0.9%), sending its benchmark Nikkei 225 index 3% lower. Additionally, Hong Kong’s Hang Seng, Singapore’s Straits Times, and South Korea’s Kospi had their worst day since March, falling 3% today.

On the heels of the notable Asian declines, European and U.S. markets are on pace for their worst day in 1.5 months. While the U.K.’s FTSE 100 is still managing to hold on to small gains this month, the other major indices have turned negative in August: S&P 500 down 0.5%, Germany’s DAX down 2.4%, France’s CAC 40 down 0.2%.

Amidst the weakness in equities, investors seem to be fleeing to the comfort and safe haven of the U.S. Dollar. The U.S. Dollar Index is now up for the third straight session to its highest level in almost 3 weeks. It is now up about 2.5% from its 11-month low hit at the beginning of August, but remains 12% off its 3-year high set back in March.

Concurrently, commodities are falling in mid-morning trading, with the energy and precious metal complexes hitting their lows of the month. For August: crude oil down 5.6%, gasoline down 5.7%, natural gas down 12.8%, gold down 2.4%, silver down 0.1%.

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