Stocks reversed course from the morning and tumbled as the NASDAQ led the selling. Mark Newton, Chief Technician at Greywolf says momentum stocks like Netflix and Tesla are losing their 'gogo' steam. As a result, these high flying tech names faltered, bringing most of the NASDAQ with it. The major indices have followed suit, although the selling isn't as pronounced. Newton is looking at the Russell 1000 for signs as to whether the selling will pick up steam.