The first model estimate comes in at 10.4%

The Atlanta Fed GDPNow tracker for Q2 growth comes in a 10.4%. It is the first look from the model. As the data starts to come in, the number will be revised lower and higher until the first release sometime toward the end of July.

In their own words:

The GDPNow model estimate for real GDP growth (seasonally adjusted annual rate) in the second quarter of 2021 is 10.4 percent on April 30. The initial estimate of first-quarter real GDP growth released by the U.S. Bureau of Economic Analysis on April 29 was 6.4 percent, 1.5 percentage points below the final GDPNow model nowcast released on April 28.
The first model estimate comes in at 10.4%