Malaysia: Hail can occur three times a year

BERNAMA New Straits Times 19 Jun 16;

KUALA LUMPUR: The hail which hit the capital earlier this month can occur three times a year, says Science, Technology and Innovation Minister Madius Tangau.

“Hail is not an unusual phenomenon, but it’s very rare in our country.

Based on our records, it can occur with a frequency of one to three times in a year,” he told Bernama here.

Madius said the phenomenon results when there is a strong thunderstorm and when the cumulonimbi clouds (the main source of the formation of thunderstorms) reached a height of 40,000 feet.

“When the temperature goes below freezing point, the rain drops become ice lumps sized between five millimetres or 1.5 centimetre, about the size of a marble.

“Hail usually occurs locally around areas under cumulonimbus clouds and lasts for a relatively short time, which is about 20 minutes,” he said.

In the hailstorm that hit the capital on the evening of June 3, Petaling Jaya Meteorological Station records show rain measuring 60.2mm and winds of up to 46.8 kilometres per hour was the cause of the phenomenon.

Madius advised people facing similar hail incidents to stay away from the window and immediately seek refuge in a safe place.

“If in a vehicle, make sure you park under a bridge or a sturdy structure,” added Madius. --BERNAMA

MJO phenomenon cause of excessive rainfall in Klang Valley
BERNAMA New Straits Times 19 Jun 16;

KUALA LUMPUR: The excessive rainfall recently, especially in the Klang Valley has been due to the impact of the Madden-Julian Oscillation (MJO) phenomenon, says an expert.

Climatology and Oceanography Specialist from Universiti Kebangsaan Malaysia (UKM) Prof Dr Fredolin Tangang said the country was currently in the midst of the Southwest monsoon season, and the weather should be hot and dry.

“The MJO phenomenon is part of climate variability between seasons in tropical regions that oscillate with the frequency of once in 20 to 60 days, which occurs in eight phases.

“MJO occurs as a result of interaction between the ocean and the atmosphere, which causes a large-scale atmospheric convection system in the western part of the Indian Ocean which moves eastward across the Pacific Ocean, crossing Malaysia and Indonesia,” he told Bernama here.

He said this when asked to comment on the massive rainfall occurring in the Klang Valley in the late afternoons, including some unusual storms, of late.

In the meantime, Fredolin said through studies conducted, the Southwest monsoon season between June to August has been found to yield higher rainfall in the west coast, compared to the east.

He said based on the report from the Climate Prediction Centre at the National Oceanic and Atmospheric Administration (NOAA) of the United States, MJO would occur in the Indian Ocean with large-scale increase in atmospheric convection in the first week of this month, and was currently in phase 3.

“This situation has led to the high rainfall rate currently experienced, similar to that in April and May, where the west coast of Peninsular Malaysia usually experiences rain in the afternoon, until late at night.

“However, this situation will only last for another one to two weeks, when the phenomenon moves more towards the east, and the centre of the convection passes our region,” he said.

He added that the country was expected to experience warmer and drier weather once MJO shifted eastwards, in phases 4 to 7 of the phenomenon. --BERNAMA

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