This long north–south traverse from Padua to Rome spans cool plains, showery Apennine crossings, and warmer central valleys, with conditions shifting markedly by elevation and latitude. April, May, and September offer milder temperatures, balanced daylight, and changeable but manageable showers across most sections, easing climbs and long lowland stretches while keeping afternoons pleasant and nights fresh. Outside these windows, midsummer heat and humidity or late‑autumn to winter damp and occasional snow shape pacing, footing, and logistics, and short, intense storms can briefly disrupt progress before rapid clearances return.