The stock market indices had yet another turn-around Tuesday, especially in the last hour when they took off and exploded. The incredible amount of pressure and short covering in the last 45 minutes to an hour was astounding.

The day started out with a big gap down. They went down to 2050 on the Nasdaq 100, and reached 1075 on the S&P 500. They then had a beautiful 5-wave rally, and went all the way back up to 2150 NDX and 1104 on the SPX. They rolled over to retest the lows and actually took them out on the NDX, but not so on the S&P 500. They got all the way back down to 1180 on the SPX and down near 2042 on the NDX. At that point they went vertically straight up into the close, from 2042 on the NDX to 2130. That was nearly an 85-point, straight-up rally. The SPX went from just under 1180 to nearly 11.25, or up 65 points.

That kind of rally is unheard of in less than an hour. It was one of the best short-covering rallies I’ve ever seen. No doubt about it.

Net on the day, the Dow went from 10,404 all the way up to 10,808. That’s more than 400 points in one day. It ended up 153.41 at 10,808.71. The S&P 500 jumped from 1074 to 1125, closing up 24.72 at 1123.95. The Nasdaq 100 jumped from 2042.90 to 2131, closing up 44.17 at 2129.21, just 2 points off the high.

Advance-declines were 3 to 2 positive on the New York Stock Exchange, and 3 to 2 positive on Nasdaq. Up/down volume was 6 1/2 to 1 positive on New York, with total volume of 1 2/3 billion shares traded today. Nasdaq traded 3 billion shares and had a 9 to1 positive volume ratio on advancing volume over declining volume.

It was a huge rally today.

TheTechTrader.com board, as you can imagine, was vastly higher. The Direxion Daily Small Cap Bull 3X Shares (TNA) was up 5.16 to 33.05, and most of that gain was in the last 45 minutes. Goldman Sachs (GS) jumped from 84.27 to 95.22, closing up 4.50 to 94.58, InterDigital, Inc. (IDCC) went from 43.93 to 48.89, up 4.26 to 48.71. Travelzoo Inc. (TZOO) jumped from 20.68 to 24.54, and closed up 3.44 to 24.46.

In addition, SodaStream International Ltd. (SODA) rose 2.64 to 31.76, Questcor Pharmaceuticals, Inc. (QCOR) 2.53 to 28.89, Universal Display Corp. (PANL) 2.45 to 44.09, and LSB Industries Inc. (LXU) 2.95 to 29.05.

There were big reversals across the board today, and too many to mention.

On the downside, the ultra-shorts did not have as good of a day. The VelocityShares Daily 2x VIX ST ETN (TVIX) got slam-dunked, going from 85.39 to 109.17, and then down 14.09 to 86.81, and trading in the after hours as low as the mid 80s. The Direxion Daily Small Cap Bear 3X Shares (TZA) got hammered, going from 49.28 to 63.87, and closed down 11.70 to 49.59. The Direxion Daily Financial Bear 3X Shares (FAZ) went from 65.88 to 81.29, closing down 8.14 to 66.66.

There were many stocks that rallied sharply. Apple Inc. (AAPL), which had rolled over hard in the afternoon from 381.80 down to 354.25 and was partially responsible for the sell-off today after news of the new iPhone, rallied to close down just 2.10 to 372.50.

So you can see why the indices rallied.

Let’s hope that tomorrow is another great day.

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