Before you open a scanner, check what happened overnight. Earnings releases, FDA decisions, analyst upgrades/downgrades, M&A announcements, and geopolitical events all create the catalysts that drive the biggest intraday moves. A stock with a catalyst and volume will trend. A stock with just volume often fades.
Where to check
Yahoo Finance's market overview page shows pre-market movers and breaking news. Your broker's news feed is another source. For earnings specifically, check the earnings calendar for companies reporting before the open. You don't need to read every article. Skim headlines. Note which tickers have news. Move on.
What to look for
The best day trading catalysts are binary events with clear outcomes: earnings beat expectations, FDA approved a drug, a company announced a major partnership, or an activist investor took a position. These create sustained directional moves because new information is being priced in. Vague catalysts (“sector rotation” or “market sentiment”) produce choppier price action that's harder to trade.
Common mistake: skipping this step
Traders who skip the news check and go straight to scanning often end up buying stocks that gapped on no clear catalyst. Those gaps fade more than 60% of the time. The five minutes you spend checking news saves you from chasing phantom moves.
Now open your scanner. You're looking for stocks that gapped pre-market with meaningful volume. The scan criteria are simple: price between $2 and $50, pre-market change above 3%, and pre-market volume above a threshold (the exact number depends on your scanner, but 100K shares pre-market is a reasonable floor). Sort by percent change, biggest gappers at the top.
This should give you 10 to 25 candidates on an average morning. More on earnings-heavy days. Fewer on quiet Fridays. Cross-reference this list against the news you checked in Step 1. Mark the ones that have a clear catalyst. Move the catalyst-backed gappers to the top of your list.
If you're using Finviz, the screener filters handle this quickly but don't have true pre-market data on the free tier. TradingView's paid tier shows pre-market data in the screener. Banana Farmer's leaderboard already scores and ranks across 9,287 assets every 15 minutes, so you can skip the manual filtering entirely and go straight to the ranked results.
Economic data drops at 8:30 AM Eastern. Jobless claims, CPI, GDP, and Fed announcements can shift the entire market. After the 8:30 data, some of your candidates will accelerate. Others will reverse. The volume filter separates the real moves from the noise.
Check relative volume (RVOL) on each candidate. You want at least 2x the average daily volume, measured by pre-market activity. A stock with 3x or 5x RVOL is attracting real institutional attention. A stock with 1.2x RVOL might be drifting on retail interest that fades at the open.
The kill criteria
Remove any stock that: has RVOL below 2x, has faded its pre-market gap by more than 50%, has a spread wider than 0.5% of price, or is trading on no identifiable catalyst. Your list of 10-25 candidates should now be 6-10. That's where the real work starts.
This is where most traders make their biggest mistake: they look at the 1-minute or 5-minute chart and ignore the daily. The daily chart tells you whether today's gap is opening into clean air or smashing directly into resistance from three months ago. A stock gapping 8% into a major resistance level is a very different setup than one gapping 8% through a breakout.
What to look for on the daily chart
Is the stock gapping above prior resistance? That's a breakout, and the old resistance becomes support. Bullish. Is it gapping into resistance from a previous high? That's a potential rejection zone. Approach with caution. Is it in a long-term downtrend gapping on news? Could be a reversal, but fading gaps on downtrending stocks is one of the most reliable day trading setups.
Define your levels
For each remaining candidate, write down three numbers: entry level (where you'll buy), stop loss (where you'll exit if wrong), and profit target (where you'll take gains). If you can't identify clear levels for all three, the setup isn't tradeable. Remove it from the list. This exercise cuts another 2-4 stocks, leaving you with 3-5 final candidates.
By 9:15 AM, your watchlist is final. Three to five stocks. Each has a catalyst, heavy volume, a clean daily chart, and a written trade plan. Close the scanner. Open your charts for these stocks. Set your alerts. Wait for the bell. The scanning phase is over. The trading phase begins.
Discipline means ignoring the stock that “just showed up” on your scanner at 9:28 AM. You didn't research it. You don't know the daily chart. You don't have a trade plan. Adding it at the last minute is how you end up chasing a random ticker and abandoning the plan you spent 90 minutes building.
After the first 30 minutes of trading, you can do one quick midday check (see our day trading scanner setup guide for that workflow). But the primary watchlist for the day was set at 9:15. That's the rule.
