ETFs are back in July.

The U.S. ETF business saw redemptions of about $12 billion in June amid Federal Reserve tapering fears, the first monthly outflow since December 2011.

However, investors are flooding back into ETFs so far this month.

“If you are looking for the source waters of the recent melt-up in U.S. stock markets, look no further than U.S. listed exchange traded funds,” says Nicholas Colas, chief market strategist at ConvergEx Group.

“Over the first 12 trading days of the new quarter, investors have added some $24.4 billion of new assets to ETFs which focus on U.S. equities, or over $2 billion per day,” he said in a note Friday. “That’s almost 4x the run rate of the first half of 2013 and simply a torrent of fresh money by even the ETF industry’s go-go standards.”

Overall, ETF creations have totaled $30 billion thus far in July.

SPDR S&P 500 (NYSEArca: SPY) has been driving the massive inflows to U.S. equity ETFs. The fund this week broke through $150 billion in assets for the first time. SPY has reeled in $12 billion so far this month, or about $1 billion a day. [S&P 500 ETF Nears $150 Billion as Assets Reach All-Time High]

“Our contacts in the industry tell us that these inflows are ‘smooth’ and not the result of a few chunky reallocations of capital by a handful of accounts. In short, that $12 billion in new money is a decent indicator of investor interest in U.S. stocks,” Colas remarked.

“Even U.S. fixed income is seeing a resurgence of interest in these first few days of the new quarter,” the strategist added.

Investors have directed $2.7 billion to this ETF segment in July. [Investors Jumping Back Into Junk Bond ETFs]

“Yes, the winners here are shorter duration products, as you would expect given the volatility in the longer end of the curve. At the same time, asset classes such as high yield corporates are back to receiving inflows,” Colas said. [Investors Buying High-Yield ETFs with Shorter Durations for Rate Protection]

Conversely, ETFs seeing outflows this month include funds tracking gold, real estate investment trusts, emerging markets, preferred shares and consumer staples stocks.

“The bottom line from this data is that investor interest is squarely focused on U.S. investments generally and domestic equities specifically,” Colas said. “Former objects of attention – emerging markets, commodities, yield plays and the like – have fallen by the wayside.  This is an all-American love affair, at least for now.”