Much of today's weakness in the equity markets can be attributed to broad weakness among European indexes. While those markets were the focus for much of the last couple weeks, that worry seemingly dissipated this week, as domestic equities rallied sharply. However, looking at price action across the pond, things are once again looking dismal.

European weakness was highlighted by the Spanish IBEX plummeting, down almost 6% on the day. The primary cause of this plunge is the Spanish 10-year bond yields, which are once again above 7%. Weakness among European bonds has led to more inflows to U.S. government bonds. The iShares Barclays 20+ Year Treasury Bond Fund (NYSEARCA:TLT - 130.10) is up sharply, over 1% on the day.

While this week's rally was a great relief from the recent fear, it appears that Europe will once again dominate the headlines (and thus, price action). Investors are shunning strong earnings from bellwether companies this week, and looking instead at potential risks moving forward. Keep a close eye on these key indexes.