The markets turned around and went south today, heading lower from the get-go as pre-market futures were sharply lower. There was an early bounce that failed immediately. Then they went lower for most of the morning until just before lunch hour when they firmed up and moved back through the lunch hour to try to retest resistance highs, and they failed right there at those levels. In the early afternoon they started a slide that accelerated to the downside. With a couple hours to go they reached their lows for the session, and then had a fairly sharp snapback after post-Fed beige book selling resulted in an intraday oversold condition. They backed and filled and were unable to get through resistance, and slipped back near the close.

Net on the day, it was a sharply negative session with the Dow down more than 143, the S&P 500 losing over 17, and the Nasdaq 100 more than 26. The Philadelphia Semiconductor Index (SOXX) was down 6 1/4.

Advance-declines confirmed today's very negative session, lower by 24 to 9 on New York and by about 2 to 1 on Nasdaq. Up/down volume was even worse, with about a 4 1/2 to 1 negative ratio on New York and about 2 1/2 to 1 on Nasdaq. Total volume was just under 1.4 billion on New York and about 1.9 billion on Nasdaq.

TheTechTrader.com board was mixed. There were several gainers and losers of more than a point. On the plus side, shipping stocks had an outstanding day relatively, with DryShips (DRYS) up 2.66, Excel Maritime (EXM) up 2.41, and TBS International Ltd. (TBSI) gaining 94 cents.

Among other gainers, a late afternoon run in Research Frontiers (REFR) exploded it by nearly $2, with the stock closing up 1.95 to 14. Fractional gainers included DG FastChannel (DGIT) up 89 cents, Nuance Communications (NUAN) 36 cents, Cree Inc. (CREE) 21 cents, portfolio position Auxilium Pharmaceuticals (AUXL) 28 cents, with ALVR up 33 cents.

On the downside, multiple point-plus losers today included Aluminum Corp. of China (ACH) down 4.07, Sigma Designs (SIGM) down 2.39, VMW down 3.24 and in the solar sector JASO was off 1.25 and LDK 1.12.

Among other large fractional losers, portfolio position Cepheid (CPHD) lost 84 cents, Hoku Scientific (HOKU) 65 cents, FuelTek (FTEK) 76 cents, and Eschelon Corp. (ELON) 88 cents. Chindex (CHDX) gave back 47 cents. The Qs and SMH both lost around 50 cents.

Stepping back and reviewing the hourly chart patterns, yesterday's spike high peaked the 4-day rally, but a late sharp sell-off triggered this morning's decline, as overdue profit-taking set in today. But the indices did manage to hold secondary resistance down near the rising 40-day moving averages on the hourly charts, and we'll see soon if this is the beginning of something steeper or just a normal pullback within an ongoing sharp uptrend.

But my inclination is that entering the weak September period we may see some further weakness.

Harry Boxer is a technical consultant to many Wall Street hedge funds and large institutional traders, and author of TheTechTrader.com, a real-time diary of his day, swing and intermediate-term trades. For more of Harry Boxer, sign up for a free 15-day trial to his Real-Time Technical Trading Diary, or sign up for a free 30-day trial to his Top Charts of the Week service.