Winter 2013 - Seasonal Outlook

1.0 Introduction

The Winter 2013 Seasonal Outlook gives an insight of the expected evolution of the climate during the winter months in Mauritius and Rodrigues. The content of this outlook is meant to be used as general guidelines for planning purposes by stakeholders in various socio-economic sectors.  Winter in Mauritius and Rodrigues has been generally defined as the period from mid-May to October. However, May and October are usually considered as transition months.

2.0 Background

Winter weather is often characterized by persistent trade winds emanating from anticyclones transiting the south Indian Ocean from west to east. Temperatures are cooler, especially during the months of June to September.

The behavior of meteorological and oceanic parameters as well as El Nino Southern Oscillation (ENSO) in analogue years are the key factors used to generate the most likely scenario for the winter months. Global, regional and local predictors are analyzed in the process of the preparation of this outlook.

3.0 Conclusions

This section applies to both Mauritius and Rodrigues

The most likely outcome for winter 2013 is as follows:

(i) Considering the fact that El Nino Southern Oscillation (ENSO) neutral conditions are likely to prevail during May to October 2013, the onset of winter will be normal.

(ii) Cumulative rainfall will be slightly below to near normal during winter 2013, in Mauritius and Rodrigues. Expected rainfall amount will be between 550 to 600 mm in Mauritius and between 320 to 360 mm in Rodrigues. The winter rains will be concentrated mainly over the high grounds, to the South and to the East.

(iii) Maximum and minimum temperatures are likely to be slightly above the mean during season. However, on few occasions, during strong anticyclone in July and August and during light wind and clear sky conditions by the end of the winter season, it is not unlikely that minimum temperatures at Mauritius may drop to 10 degrees Celsius at some places over the high grounds.

At Rodrigues, minimum temperature may drop to near 14 degrees Celsius over the high grounds.

The Table below gives the forecast maximum and minimum temperatures in degrees Celsius for the different region of Mauritius as well as for Rodrigues (Pointe Canon) for May to Oct 2013.

(iv) Wind speed is likely to be moderate (20-25 km/h) most of the time. Occasionally, during the peak winter months of July and August, during the passage of strong anticyclones to the south of the Indian Ocean, wind gusts are likely to be of the order of 90 km/h over exposed areas.

(v) On some occasions, seas will become very rough with traveling heavy swells originating far to the south of Mauritius.

Mauritius Meteorological Services

Vacoas

02 May 2013