The Rockies scored first and then came the Astros' 14-hit explosion.
Lee's big night started with a two-run double that was part of a franchise-record six consecutive hits to start the first inning. The Astros took a 5-1 lead off rookie Drew Pomeranz (1-1), who was making his third major league start.
"The biggest thing for us offensively was to be able to answer back in that first inning," Astros manager Brad Mills said. "Getting those six straight hits, it was good to see us answer back."
Lee became the first Astro to have consecutive four-RBI games since Lance Berkman on May 30-31, 2000, against Colorado.
"He's swinging the bat extremely well to be where he is," Mills said. "To be able to come back like that and do what he has this whole second half has been good."
Myers (7-13) struck out six, walked one and retired the last 11 batters he faced. Before starting his winning streak, Myers had lost seven straight decisions. He is 8-1 lifetime against Colorado.
"I wish I'd started out this way," Myers said. "It didn't work out so you go out and try to compete. I've been keeping the ball down. Early in the year the ball was elevated a lot. That's usually when I get hurt. I just try to keep it down."
Lee had an RBI single in the fourth and an RBI groundout in the fifth. Clint Barmes added a solo homer, his 12th, in the sixth.
Pomeranz lasted two innings, allowing seven hits and six earned runs. Pomeranz had allowed two earned runs in 10 2/3 innings in his first two starts.
"Unfortunately tonight, for Drew, it didn't happen," Rockies manager Jim Tracy said. "There was no life to his pitches like he has seen the last two starts. The ball was flat, and obviously, that was evident by some of the at-bats taken in the bottom of the first inning."
J.B. Shuck led off the game for Houston with a single and scored on a double by Angel Sanchez to tie it 1-1. Lee's double scored both runners and a double by Matt Downs and single by Chris Johnson made it 5-1.
Finally, Barmes flied out and Humberto Quintero and Myers struck out the end the inning.
"Everything was up. That's pretty much all there was," Pomeranz said. "I've had stuff happen like that before but not very often. I looked back at all those balls, and they were bad pitches by me."
The Astros have had numerous games with five hits to start the first inning, most recently June 6, 2010, against the Cubs.
"We started the game sending two hitters to the plate, and we had an infield hit and an RBI double and a man on second with nobody out," Tracy said. "In order for us to play competitive baseball and win a couple games, the way it has to happen is we're going to need someone to go out there on that mound and give us a quality start."
Colorado's Matt Downs has 15 pinch-hit RBIs and needs three more to set a franchise record set in 2001 by Orlando Merced. Jordan Pacheco has nine RBIs in his first 14 major league starts for the Rockies. Carlos Gonzalez is the first player in Rockies history with consecutive seasons with at least 20 home runs and 20 stolen bases. Henry Sosa doubled for his first career hit on Thursday. He was the sixth Astro to get his first major league hit this season.