We had a very interesting session today, a big opening gap down as futures were lower all evening. The markets immediately stabilized, rallied sharply, and then backed and filled in a bullish fashion that led us to believe we would see an extension, and we certainly got a strong one. The indices exploded into early afternoon, reaching near 1600 on the NDX and 1000 on the SPX before an afternoon pullback brought them back, but when they failed to break down any further, they snapped back in the last hour to close not far off the session highs.

Net on the day the Dow was up 61.22 at 9279.16, which was 148 points off the low. The S&P 500 was up 6.79 at 996.46, 16 points off its low, and the Nasdaq 100 gained 10.11 to 1596.61, 30 points off its low.

So a strong comeback session for the indices today, but on lower volume.

The technicals managed to move back into the positive column by 3 to 2 on advance-declines on New York and a like amount on Nasdaq. Up/down volume was 3 to 2 positive as well on New York on total volume of a light 970 million. Nasdaq traded over 1.9 billion and had about a 2 Ã,½ to 1 positive volume ratio.

As a result of all the swings, many stocks on our TheTechTrader.com board closed narrowly mixed, but there were some outstanding gainers.

On the upside, low-priced biotech Cerus (CERS) closed at 2.88, up 1.09 on 21.2 million, a gain of 61% today, but about 65 cents off its high. American International Group (AIG) had a strong session, jumping from 23.90 to 27.50, closing at 26.64, up 2.09 on 31.8 million.

Rambus (RMBS) also had a very strong session, jumping from 16.91 to 18.85, closing at 18.66, up 1.38 on 7.2 million.

OncoGenex Pharmaceuticals (OGXI) closed at 30.18, up 1.44, but traded just 36,000 shares.

The U.S. Oil Fund ETF (USO) was stronger today on firmer oil, up 1.26 at 38.12.

The ultra ETFs we follow were very narrowly mixed, both up and down.

There were no losers of more than a point, but China Green Agriculture (CGA) did give back 96 cents to 12.49, and Goldman Sachs (GS) lost 55 cents to 159.93. JP Morgan (JPM) lost 29 cents to 41.41, but Wells Fargo (WFC) and Morgan Stanley (MS) were both up small fractions.

Low-priced junior biotech SIGA Technologies (SIGA) jumped 60 cents to 7.69, and new portfolio addition Planar (PLNR) added 27 cents to 3.04, breaking out to 11-month highs today.

Oncothyreon (ONTY) gained 38 cents to 5.40 and BioCryst Pharmaceuticals (BCRX) was up 23 cents to 10.04.

Stepping back and reviewing the hourly chart patterns, the indices opened sharply lower, then turned it around in strong a 3-wave advance, before an afternoon pullback took them back a bit. But a late surge managed to gain back half of the late losses and close with substantial gains on the day.

However, on the hourly charts there is clear overhead resistance at today’s highs at 1600 NDX and 1000 SPX. Those resistance levels should be closely watched tomorrow.

Harry Boxer is a technical consultant to many Wall Street hedge funds and large institutional traders, and author of TheTechTrader.com.