Understanding the Polar Vortex and Its Impact on Mexico’s Climate
The polar vortex, a mass of cold air surrounding the Arctic, plays a significant role in shaping Mexico’s climate during the winter months. The sudden stratospheric warming phenomenon is expected to modify the behavior of the vortex, allowing it to extend southward and send Arctic air towards lower latitudes.
This, combined with the negative phase of the Arctic Oscillation, will favor the formation of atmospheric blockages that will direct cold air masses towards Mexico. As a result, the country can expect intense frosts, especially in mountainous areas, and the possibility of snowfall in some regions.
Regional Climate Variations in Mexico
The effects of the polar vortex will be felt across various regions in Mexico, with the northern, northeastern, central, and eastern states being the most affected. Temperatures below normal are expected, with some areas experiencing record minimum temperatures.
States such as Chihuahua, Sonora, and Coahuila will experience temperatures ranging from -10 to -5 °C, while areas like Baja California Sur, Sinaloa, Nayarit, Nuevo León, Mexico City, and Morelos will experience temperatures between 0 to 5 °C.
Climate Mechanisms and Their Impact on Mexico
The quasi-biennial oscillation, a long-term climate pattern, is in a phase that favors the entry of cold air towards the south. Additionally, the La Niña phenomenon, although variable this year, contributed to creating the atmospheric conditions necessary for the cold air from the Arctic to move towards Mexico.
Changes in the upper atmosphere will be reflected on the Earth’s surface through the Arctic Oscillation, the North Atlantic Oscillation, and the East Pacific Oscillation, which will enter a negative phase, causing atmospheric blockages that will favor the movement of cold air masses towards the south.
Precipitation Patterns in Mexico
Despite the low temperatures, Mexico will also experience precipitation, particularly in the states along the Gulf of Mexico and the southeast of the country. Veracruz, Tabasco, Campeche, Yucatán, Quintana Roo, and parts of Oaxaca and Chiapas will be the most affected, with accumulated rain exceeding 200 millimeters in some areas.
The mountains of the Neovolcanic Axis and the Madre Oriental and Occidental mountain ranges are expected to experience events of rain, hail, and, in exceptional cases, snow. Although a cold winter with precipitation is expected, it does not mean that the entire month will be like this.