MyCruiseForecast

Costa Cruises · 3 nights

Costa Diadema weather: 3-night cruise from Itajaí, December 16, 2026

The Costa Diadema (Costa Cruises) leaves Itajaí on December 16, 2026 for a 3-night cruise, with stops in Santos (Sao Paulo). It returns to Itajaí on December 19, 2026. Typical afternoon highs along the route run from 84°F to 87°F (29°C to 30°C), and 1 day is at sea, where seas are typically slight (around 4 ft).

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This page shows typical conditions for these dates. The interactive forecast adds a live day-by-day forecast, wave heights and weather alerts as the sailing gets closer.

Day-by-day itinerary and typical weather

Typical conditions for each date (2006–2025 climate record, ECMWF). Sea-day figures are approximate, blended from the ports on either side. Not a forecast.
DayPortHigh / lowRain daysWindTypical seas
Day 1Wed, Dec 16Itajaí Embark87 / 72°F30 / 22°C46%10 mph16 km/h–
Day 2Thu, Dec 17At sea85 / 72°F30 / 22°C48%7 mph11 km/h4 ft (1.1 m)Slight; rougher days up to 5 ft
Day 3Fri, Dec 18Santos (Sao Paulo)84 / 72°F29 / 22°C49%9 mph14 km/h–
Day 4Sat, Dec 19Itajaí Disembark87 / 72°F30 / 22°C46%10 mph16 km/h–

Seas are significant wave height, the average of the highest third of waves. What that means on board.

Ports on this cruise

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