December: Slightly Rising Temperatures

Title: December: Slightly Rising Temperatures

Content: The forecasts for December, January, and February indicate a stable summer, with moderate rainfall and slightly above-average temperatures. This information is included in the latest report from the Vacoas meteorological station.

Mauritius is entering the summer season with relatively balanced weather conditions, according to the recent report from Vacoas. November, often seen as a transitional month towards the hot season, experienced above-average rainfall, recording 140 mm, which is 165% of the normal amount. This increase was particularly notable in the eastern part of the country, where some stations recorded up to 247 mm, equating to 227% of typical climate values. This situation suggests that December will start off in a humid context, although forecasts do not anticipate major disturbances.

Meteorologists expect about 150 mm of rain for December, which corresponds to 91% of the seasonal average, placing the month within a normal range. For the early months of 2026, the trend remains similar. January could see around 270 mm of precipitation, while February is projected to receive nearly 300 mm, representing 96% and 93% of the respective averages. Climate models indicate a possibility of occasional excess, but the report concludes with a scenario of regular rainfall without prolonged heavy rain episodes.

Temperatures are another significant indicator of this transition towards the austral summer. The report shows that the Vacoas and Plaisance stations recorded positive anomalies in November, with increases of +0.9°C for minimum temperatures and +1.4°C for maximum temperatures. In Plaisance, temperatures hit 31.6°C, indicating an already warm atmosphere. This trend is expected to continue over the next three months, with forecasts indicating slightly above-average temperatures, though not reaching unusual levels for the summer period.

Several factors explain the current climatic configuration. A weak La Niña persists in the equatorial Pacific, influencing global atmospheric circulation. At the same time, the Indian Ocean is currently affected by a negative Indian Ocean Dipole (IOD), which also alters air and heat exchanges in the region. According to the report, these elements, combined with slight pressure anomalies in the Mascarene region, are contributing to a hot start to summer, without any significant signs of a notable drift. The report also analyzes the evolution of the standardized precipitation index (SPI), used to measure periods of prolonged drought or humidity. After the dry spells noted earlier in the year, the index now reflects a value categorized as “near normal.” Forecasts for the upcoming months remain within this configuration, indicating a stabilization of water levels nationwide. Thus, according to Vacoas specialists, Mauritius is heading towards a summer where rainfall should be well-distributed and temperatures moderately high.

La Niña is a climatic phenomenon characterized by an abnormal cooling of the surface of the equatorial Pacific Ocean, mainly off the coasts of Peru and Ecuador. This cooling alters air circulation, wind intensity, atmospheric pressure, and global rainfall patterns. Its effects can indirectly influence the climate of the Indian Ocean. In the region, its impact often depends on other phenomena such as the Indian Ocean Dipole (IOD). The interaction between these systems can modulate precipitation, temperatures, or even the formation of tropical systems. In general, La Niña can promote slightly higher temperatures in the southwestern Indian Ocean. Rainfall may remain near normal or slightly above depending on atmospheric conditions, and it may sometimes be associated with more pronounced tropical activity, with variability from year to year.