U.S. retail sales could benefit from a high savings rate in December and colder weather in January. Above, a shopper is seen carrying JC Penney bags in New York City in 2011. Getty Images

It's been a rough week for financial markets. The Dow Jones Industrial Average has dropped 3.4 percent from the start of the week, with gauges of investor fear spiking to six-month highs on worries about slowing global economic growth. But the week could end with a rare bit of good news Friday morning when the Commerce Department reports retail spending for the month of January.

Analysts polled by Bloomberg predicted a small but positive increase of 0.2 percent month over month for the start of 2016. That wouldn't be an earth-shattering number, but it could be a relief coming after a disappointing drop of 0.1 percent in December, which made 2015 the weakest year for retail spending since 2009.

Retail sales provide insight into overall consumer spending, which makes up two-thirds of the U.S. economy. In the last quarter of 2015, consumer spending contributed 1.5 percent to the growth in gross domestic product, buoying the economy against headwinds from sluggish exports. Consumer spending data also include several sectors, like health spending, that are not captured in retail sales.

Investors are hoping that a three-year high in U.S. savings in December translated to increased spending in January. Rising wages in December and January, together with cheaper gas, provided further buying potential for retail customers.

Another potential boon: Vehicle sales exceeded expectations in January, with the strongest start to a year since 2006. Retail sales figures excluding autos, which tend to be a more volatile category, are expected to come in at a month-over-month gain of 0.1 percent.

Weather also could have played a part in December's sluggish retail sales, with every state in the Lower 48 recording higher-than-average temperatures for the month. That means consumers were likely to have put off their winter gear buying for later.

The Commerce Department reports retail sales at 8:30 a.m. EST.