If patterns are any indication, than S&P 500 should see an imminent sell off. Back in October of 2018, when market tested lower line of the channel and was rejected, we saw a sell off. Now we have a very similar pattern where the bottom line of the channel has been rejected. Any break below 2800 could be the catalyst. My assumption would be that this sell off would not last as long as October of 2018 since the channel is not as wide.