Overview
- Mexico’s SMN/Conagua says Cold Front 25 will enter between Dec. 29 and 31, driving a sharp cool-down, heavy rain and an intense Norte event along the Gulf and Isthmus.
- Officials forecast rains from strong to torrential in Veracruz and Tabasco with intensas in Puebla, Tamaulipas, Oaxaca and Chiapas, plus coastal winds of 90–110 km/h and waves of 3–5 meters that threaten navigation.
- Very low temperatures and frosts are expected in highlands, with minima of −10 to −5 °C in serranas of Baja California, Chihuahua and Durango, and possible snow or sleet in Chihuahua and on high peaks such as Pico de Orizaba and Cofre de Perote.
- Argentina’s SMN maintains yellow to orange heat alerts for Buenos Aires/AMBA and central–northern provinces, with a forecast peak near 38–40 °C on Dec. 31 and heat likely lingering into early January before easing.
- Health and activity guidance includes frequent hydration, avoiding peak sun, lighter clothing and reduced training intensity, with SMN projecting roughly 45% higher thermal stress in summer 2026 that could raise future heat-wave risk.