Weather forecasting in the tropics is a challenge

Forecasting in tropics no stroll in the park
Straits Times Forum 3 Jul 09;

I REFER to Tuesday's letter by Mr Ng Meng Keiw, titled 'Weather forecasts' (below).

Weather forecasting in the tropics is a challenge. Singapore's tropical weather is characterised by showers and thunderstorms which are usually localised and of short duration.

Such weather systems develop randomly and quickly. Furthermore, their development is largely determined by the prevailing winds which are often light and variable at the Equator, adding to the difficulty in prediction.

We sympathise with Mr Ng that his activities did not materialise as he had planned on those days. As the showers then were localised and not widespread over the east, one could have been in the part of the eastern sector that was not affected by the showers, even though dark clouds could have been observed in the vicinity.

The Meteorological Services Division (MSD) of the National Environment Agency recognises that there have been occasions when service delivery did not meet customer expectations and understand the public's need for accurate forecasts.

However, we would like the public to understand that even with the present state of science and technology, there will be weather phenomena that will remain inherently unpredictable. It is neither possible nor plausible for a meteorological centre to always achieve an accurate forecast. A reasonable accuracy rate of weather forecast in most meteorological centres is 75 to 85 per cent and MSD's accuracy rate is within this range.

All these notwithstanding, MSD will continue to improve our weather forecast capabilities with more reliable prediction models, forecasting tools and ongoing training of our officers.

We thank Mr Ng for his feedback and appreciate his understanding of the constraints of weather forecasting.

Foong Chee Leong
Director-General Meteorological Services
National Environment Agency

Weather forecasts
Straits Times Forum 30 Jun 09;

'Except for a few dark clouds, it has hardly rained there.'

MR NG MENG KEIW: 'The weather department has forecast heavy showers in the east for the past five days. However, except for a few dark clouds, it has hardly rained there. The weather department is supposed to be a high-tech organisation with satellite surveillance and such poor forecasting is not acceptable. It has an impact on how we plan our daily activities. I suggest this organisation be audited, like the public transport system. A target can be set, for example, 95 per cent of forecasts should be accurate.'