Stocks staged a monstrous rally today after extreme oversold conditions triggered overnight futures higher.

The indices opened with a gap up, consolidated in the morning, on the S&P 500 in particular, but the Nasdaq trended higher all morning until they reached key overhead resistance at 2040 mid-morning. The S&P at that point reached resistance at around the 1460-62 zone. They backed off in a very orderly manner, retested successfully, and then staged a strong afternoon rally, especially on the blue chips, with the S&P from just after lunch rising from 1455 to 1481.

Net on the day, the Dow jumped back over 13,300 closing at 13,307, up 319 1/2. The S&P 500 was up nearly 42, the Nasdaq 100 up 84, and the Philadelphia Semiconductor Index (SOXX) up nearly 10.

Advance-declines were about 27 to 6 positive on New York and 21 to 9 on Nasdaq. Up/down volume was the story, though, about 15 to 1 positive on New York on total volume of about 1 2/3 billion. Nasdaq had about a 12 to 1 positive ratio on total volume of about 2.7 billion.

TheTechTrader.com board was very active, and sharply higher, with some major dollar gainers. BIDU jumped 43 points, closing at 344.60. GOOG was up 27 1/2, AAPL up 16 1/4, DRYS up 11.70, TBSI up 7, EXM 7 3/4, and VMware (VMW) up 10.32.

Other gainers of note, Aluminum Corp. of China (ACH), a portfolio position, was up 4.46. Sigma Designs (SIGM) added 2.07, Global Solutions (GSOL) 3.29, and GIGM 4.67. Junior solars had a good day, with CSIQ up 1.23, Ascent Solar (ASTI) up 1.15, and Evergreen Solar (ESLR) up 77 cents.

On the downside, the ultrashort instruments obviously had a very negative day, with the SDS down 3.47, the QID 3.30, and the DUG 1.96.

So, a very strong day for the bulls today, as the indices closed near the high for the day going away. We're near overhead resistance or approaching it. Key overhead resistance to watch tomorrow is around 1490 on the S&P and around the 2080 level on the Nasdaq 100.

We'll see if we can get a solid follow-through, but today was certainly one of the stronger days we've seen in a while. But we weren't surprised, as we noted in last night's comments that we expected a strong snapback.

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.