The S&P 500 and the Dow hit record intraday highs on Tuesday, while the Nasdaq turned positive for the first time this year, buoyed by rising prospects of global economic health and with Alcoa getting the US earnings season off to a promising start. The S&P 500 hit 2,155.32, breaking past its previous record on Monday. The Dow hit an all-time high of 18,360.51.
Alcoa's quarterly profit fell less than expected, sending the aluminium producer's shares to a five-month high of $10.67 and helping boost optimism about the earnings season.
Strong economic data and low returns on government bonds along with easing political tensions in Britain and Japan have reduced some global uncertainties and boosted investor appetite for equities.
"There are no good alternatives, from an income standpoint, to the US equity markets at this point, and that's driving the momentum today," said Bill Northey, chief investment officer at Private Client Group of US Bank.
"But we need to see some supporting earnings growth to accompany this move."
While profits of S&P 500 companies are estimated to have fallen 5 percent in the second quarter, mirroring the first, analysts see a return to growth throughout the second half of the year, according to Thomson Reuters data.
At 12:23 pm ET the Dow Jones industrial average was up 128.78 points, or 0.71 percent, at 18,355.71.
The S&P 500 was up 17.16 points, or 0.8 percent, at 2,154.32.
The Nasdaq Composite was up 40.59 points, or 0.81 percent, at 5,029.23.