A shake-out at the open on Thursday would probably spark a short-covering rebound because the VXO volatility index is now at a short-term extreme and if the VXO can move back below 13.73 in Thursday's market that should coincide with an oversold rebound. This will probably only be a short-term event.
Ideally, a gap lower on the open would signal that sellers had tossed in the towel (short-term) and this would open the door for short-covering rebound. But in Wednesday's market, the Nasdaq closed below 2107.70; studies that I have done of volume and price movement carry heavy odds that the markets are not finished on the downside. (even though a short-term rebound can unfold on Thursday). And, quite often it is a base forming process (daily charts) that can take some time to unfold.
On the chart of the Nasdaq, I am focusing on the Nasdaq 2087-2072 area as a potential short-term bottom unless there are material changes in the measures I am watching. This is not necessarily expected on Thursday. I think it will take a little time to form a base in the daily charts and due to the Nasdaq's undercut of 2107.70, I expect additional downside and must wait until there are clear and valid signs of a bottom.
The Nasdaq has intraday resistance 2115-2127.24. Next resistance is 2139-2167.00 resistance gets thick 2149 and higher.
S&P 500 resistance is intraday 1203-1210.34, then 1215-1222.
The Nasdaq has support 2106-2039 there is a focus of support 2087-2070.
The S&P 500 has immediate intraday support 1206-1165 with a focus of support 1206-1183. This is a very strong layer of support and is expected to hold on this first test.