Corning Inc. (NYSE:GLW) stock is surging on Tuesday as part of a strong post-earnings relief rally.The move is further fueled by a major Wall Street upgrade following the stock’s recent decline. While the stock initially tumbled last week due to lighter-than-expected third-quarter sales guidance, investors are aggressively buying the pullback.Nasdaq futures are up 1.04% while S&P 500 futures have gained 0.33%.Analysts Reiterate Bullish OutlookThe stock carries a Buy rating with an average price forecast of $155.79 across 32 analysts. Recent analyst actions include Truist Securities upgrading Corning to Buy while lowering its price forecast to $175 on Aug. 3.On July 29, Morgan Stanley maintained an Equal-Weight rating and lowered its price forecast to $165. On the same day, Oppenheimer maintained an Outperform rating while adjusting its price forecast to $200.Strong Second-Quarter PerformanceFor the second quarter, adjusted earnings rose 30% year over year to 78 cents per share, topping estimates of 76 cents. Revenue increased 17% to $4.74 billion, beating the consensus estimate of $4.61 billion.For the third quarter, Corning expects revenue between $4.9 billion and $5 billion, aligning with the $4.97 billion consensus.They anticipate adjusted earnings of 85 cents to 89 cents per share for the third quarter.Management projected a 19% sales compound annual growth rate from the fourth quarter of 2026 through the fourth quarter of 2030.Critical Technical Levels for Corning StockFrom a trend perspective, Corning is still in a mixed posture: it’s trading 0.7% below its 20-day SMA ($159.83), but it remains 17.1% above its 200-day SMA ($135.55), which keeps the longer-term uptrend intact even after the recent pullback. The catch is the stock is still trading 12.7% below its 50-day SMA ($181.80) and 7.1% below its 100-day SMA ($170.85), so the intermediate trend needs more repair work.The moving-average structure also explains why rebounds may be choppy: the 20-day SMA is below the 50-day SMA (a bearish crossover), even though the 50-day SMA is still above the 200-day SMA (a bullish longer-term backdrop).