US STOCKS-Wall Street surges in end to volatile week
* Crude up as cold wave boosts short-term demand
* Apple rises after Piper Jaffray says buy
* GE, American Express biggest losers on Dow
* Indexes up: Dow 1.09 pct, S&P 1.75 pct, Nasdaq 2.26 pct (Updates to afternoon)
By Noel Randewich
Jan 22 (Reuters) - Wall Street surged on Friday and was on track for its first positive week of 2016 as a cold snap in the United States and Europe sent oil prices sharply higher.
All 10 major S&P sectors rose, led by a 3.5-percent jump in the S&P energy sector.
Crude prices, recently under pressure from a global glut, recovered 9 percent as harsh winter weather boosted demand for heating oil and traders cashed in short positions following a steep drop this month.
After dropping earlier this week to 2014 lows, the S&P 500 has recovered 2.5 percent in the past two sessions. But it is still down 7 percent in 2016 and remains at levels touched last August when fears of trouble in China's economy rattled global markets. Continuación...