The US economy is once again teetering on a fine line: Barclays has described its current state as "stalling"—the economy is still growing, but so sluggishly that it could be the onset of a slowdown. According to the bank’s updated model, the likelihood of a recession within the next eight quarters is around 50%.

Barclays clarifies that a full-blown crisis will hardly break out, but rather a "precursor"—a phase where growth slows enough to raise the risk of a recession, even though a recession has not been officially recorded yet.

Against this backdrop, expectations of a Federal Reserve rate cut in September are starting to look less like academic forecasts and more like a matter of political and economic common sense.

As for market dynamics, hedge funds and institutional investors were actively buying stocks in August amid fading volatility. Meanwhile, traditional market players—long-only managers and commodity trading advisors—opted to buy bonds. It seems some market participants decided to take a risk, while others remembered the old saying about "safe harbors."

However, Barclays warns, if nonfarm payrolls data starts to show a downtrend, this fragile balance could shift, increasing pressure on equities, despite the fact that broad stock buying was the catalyst that fueled the summer rally in the first place.