Here comes GDP ...

The advance estimate of US gross domestic product in the second quarter will be published at 8:30 a.m. ET.

Economists forecast an improvement in growth from the first quarter, at an annualized pace of 2.5%, according to Bloomberg.

The Commerce Department will also publish its annual revision spanning Q1 2013 through Q1 2016, and so it's possible that the sluggish 1.1% pace reported last quarter is changed.

Personal consumption is forecast at a solid 4.4% rate, indicating that spending is still a huge force driving the economy. Control group retail sales, which feed into the consumer spending component of GDP, is running at a three-month annualized rate of 7.4%.

The housing market is expected to have made a less significant contribution to growth, following a slowdown in private residential investment in Q2 compared to Q1.

Business inventories are forecast to continue to be a drag on growth. On Thursday, the Atlanta Federal Reserve's GDPNow model slashed its GDP forecast to 1.8% from 2.3%, partly reflecting a smaller contribution of inventory investment to growth.

More to come ...