Here comes GDP ...

Here comes the big one: the advance estimate of fourth-quarter gross domestic product (GDP) will be released at 8:30 a.m. ET.

Economists believe that US economic growth slowed in the fourth quarter and are expecting a 0.8% print from the Department of Commerce, according to Bloomberg.

That would make it the slowest quarter in 2015 since Q1, when the economy contracted by a smaller-than-expected 0.2%.

In a client preview, BNP Paribas wrote, "With multiple headwinds hitting the economy, including low commodities prices, weak external demand, and a strong dollar, final domestic demand is projected to have slowed considerably as well (1.3% q/q saar vs 3.0% previously). Consumption will likely be the largest contributor to growth."

The headline GDP print will be accompanied by personal consumption data, which accounts for over two-thirds of GDP and is expected to slow to 1.8%. Consumers are in the front seat of the economy, and the data could show that they are clutching their wallets tighter.

We'll also get personal consumption expenditures, the Fed's preferred measure of inflation that gauges the prices paid for everything except volatile energy-related items. Core PCE is expected at 1.2%.

Lastly, the big dump will include the employment cost index, which gives more insight into compensation than average hourly earnings. The ECI is expected at 0.6%.

We'll have all the details at the bottom of the hour, so refresh this page for updates.