Yes, it is often significantly colder at the summit of Mount Vesuvius than it is at sea level in Naples or Pompeii. The crater rim sits at an altitude of 1,281 meters (approx. 4,200 feet), and the temperature typically drops by about 6°C to 10°C (11°F to 18°F) compared to the base. In March 2026, while the city below might enjoy mild spring temperatures around 16°C (61°F), the summit can be a chilly 6°C to 10°C, often exacerbated by strong, biting winds that sweep across the Bay of Naples. During the winter months, temperatures at the top can drop to near freezing, and light snow is not uncommon. Even in the height of summer, the peak can feel brisk if a cloud layer moves in or the wind picks up. For any visitor in 2026, the "gold standard" is to dress in layers; even if you start your hike in a T-shirt, you will likely want a windbreaker or a light fleece once you reach the exposed crater rim. Sturdy, closed-toe hiking shoes are also a must, as the volcanic "scree" (loose rock) is slippery and does not provide much insulation for your feet.