More broadly, economic growth has remained muted or worse. The most recent reading of the ISM manufacturing index indicated contraction in the sector, while GDP growth for the fourth quarter is expected to run at a 1.9 percent rate, according to the Atlanta Fed. Market data provider TrimTabs said its running gauge of economic conditions is at lowest level since mid-March.
What all the data points are likely to add up to is a Fed providing what many on Wall Street are terming a "dovish hike," or an increase that will be accompanied by certain language that the Fed will tread carefully in 2016.
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"Chair Yellen's press conference should offer a cautious message," Goldman Sachs economists Jan Hatzius and Zach Pandl said in a report for clients. "We expect her to underscore that policy is not on a preset course, and that the subsequent pace of rate hikes will be highly sensitive to incoming information — including data on activity and inflation, as well as financial conditions."
The Goldman duo believes that economic metrics are "broadly cooperating" with the Fed economic outlook.
However, what may in the end be the main driver of Fed policy is simple market expectations, with CME traders pricing in an 83 percent chance of a rate hike. The Fed backed off on a much-expected September rise at a time when traders lodged very low expectations for a hike, despite similar economic conditions to what is transpiring as the year comes to a close.
"We believe the future course of Fed policy depends mostly on how financial markets respond to the Fed's words and actions," David Santschi, CEO of TrimTabs, said in the narrative accompanying the firm's weekly market breakdown. "If stock prices rise into early next year, the Fed could raise rates a couple times next year. If stock prices keep heading lower, however, a rate hike this week is likely to be the last one for a while."
It's not just stock prices that have struggled.
While the S&P 500 has fallen more than 2.6 percent in December, the commodity wipeout continues. Natural gas has tumbled 51 percent year to date, copper is down 25 percent and gold is off 10 percent.
It's hardly the environment that screams for a rate hike to slow down an overheating economy.
"Modern central banking is as much an exercise in effective communication as it is economic analysis," Nick Colas, chief market strategist at Convergex, said in a note. "Something simple like 'We're going to raise rates' is fairly straightforward, even if it took the Fed the better part of a year to get it across to capital markets. Now, they must set the stage for future hikes."
Setting that stage in such a tenuous environment for the markets and economy will require a high level of skill.
Regardless, Colas thinks the markets at least will remain volatile. In the week heading into the Fed meeting, the CBOE Volatility Index, a popular gauge of market unease, has surged more than 48 percent.
"Yes, the market always climbs a wall of worry, and U.S. equities feel oversold at current levels. The point here is not that the end of the world is nigh as much as the world is getting incrementally complex in ways that don't get a lot of attention," Colas said. "All that is an argument for further volatility not just into holiday 2015 but well into the new year."