Prévision estivale 2010-2011
C’est ce qui ressort du 2010-2011 Seasonal Outlook de la station météorologique de Vacoas avec des jours ou il fera 35 degres centigrade.
Situation météorologique le 21 octobre 2010
En ce qui concerne du nombre de tempêtes qui seront nommées durant l’été 2010/2011, il sera autour d’environ huit à 10 comme c’est le cas chaque année. Ces phénomènes atmosphérique évolueront dans le bassin du sud-ouest de l’océan Indien.
Il y aurait une probabilité qu’une tempête soit nommée dans la seconde moitié de novembre. C’est ce que révèle le “seasonal outlook” pour la saison estivale publié par la station météorologique de Vacoas. L’été débute officiellement le 1er novembre 2010 et durera jusqu’au 15 mai 2010.
Ce rapport dit aussi que les tempêtes qui vont se développer au sud de l’océan Indien et ne seront pas nécessairement une menace direct pour Maurice et Rodrigues. La pluviométrie sera peut être légèrement inférieure à la normale en début de saison et normale vers la mi-saison. La cumulation des pluies sur Maurice est d’environ 1 345 mm en moyenne et environ 725 mm sur Rodrigues. Des précipitations isolées sur des zones localisées commenceront début du décembre.
Introduction
Since several years, the Mauritius Meteorological Services issues at the beginning of the summer season a report, giving an indication of the expected evolution of the South West Indian Ocean (SWIO) summer, namely, the likely cyclonic activity during the coming cyclone season, summer rains and the temperatures in Mauritius and Rodrigues. The normal cyclone season starts officially around 01 November and terminates around 15 May of the following year, though it is not unlikely that at times cyclones do form outside these dates.
The contents of this outlook are meant to be used as general guidance for planning purposes by stakeholders in various sectors.
General Background
Correlations between some parameters such as sea surface temperature, El Nino Southern Oscillation, cross-equatorial flow, and cyclone activity in the SWIO and summer rainfall over the Republic of Mauritius have been fairly well established. Analysis, through persistence and linear combination of empirical results, have been utilized in order to generate as objectively as possible, the most likely scenario for the 2010-2011 South West Indian Ocean Summer.
Weightage has also been given to the statement of the fourteenth Southern Africa Regional Climate Outlook Forum (SARCOF) and Numerical Weather Prediction (NWP) model products from Global Producers of Long Range Forecast (GPLRF).
Conclusions
After carefully analyzing the behavior of all indicators and taking into consideration analogue patterns, it is therefore concluded that:
i) The number of named storms for the 2010-2011 summer season will be around 8 to 10 in the South-West Indian Ocean basin with a probability of a named storm in the second half of November.
All named storms that will develop in the South Indian Ocean will NOT necessarily approach the islands of the Republic of Mauritius or be a direct threat. Statistical analysis show that on the average at least one tropical storm evolves within 100 km of Mauritius and/or Rodrigues.
ii) Rainfall may be slightly below normal at the start of the season and normal as from mid-season. Please note that the cumulative rainfall over Mauritius is about 1345 mm on the average and about 725 mm over Rodrigues. Although isolated rainfall over localized areas will start by early December. Heavier summer rains are expected to start as from late December 2010. Cumulative rainfall for summer will be near normal.
iii) It is likely that as from January atmospheric conditions will periodically become conducive to the occurrence of extreme weather events such as torrential rains and strong winds that may adversely affect weather locally. Damages resulting from excessive rainfall, in the form of severe flash floods, are likely to be more significant.
iv) Temperature will be generally above the long-term mean. However, on a few days it is expected that temperatures will exceed the normal by about two degrees Celsius. Maximum temperatures reaching 35 degrees Celsius are not to be excluded on coastal areas on a few occasions.
Above normal maximum temperatures with high humidity and calm wind conditions over extended periods of time, especially in the months of December up to the beginning of April, can cause severe discomfort to the vulnerable groups of the population, It is therefore not excluded that above normal temperatures giving rise to torrid conditions will be experienced.
