Friday, August 18, 2017

Dept forecasts strong monsoon

Workers in downtown Yangon during a rainshower on May 5. Seng Mai/ The Myanmar TimesWorkers in downtown Yangon during a rainshower on May 5. Seng Mai/ The Myanmar Times

The early and peak periods of this year’s monsoon are expected to be moderate-to-strong in intensity, the Department of Meteorology and Hydrology (DMH) said in a monsoon outlook bulletin released on April 28.

According to the bulletin, the southwest monsoon will enter the southern part of the country in the second 10 days of May and advance into delta areas from May 21 to the end of the month.

The bulletin said the monsoon is expected to advance to central and northern parts of the country in the first 10 days of June.

The department has forecast that the monsoon will withdraw from the country in the first 10 days of October.

If the forecast is accurate the result would be a normal length monsoon, the department said

Monsoon intensity in the early monsoon season, which runs from the onset to the end of June, and peak monsoon season – from July 1 to the end of August – will be moderate to strong, the bulletin said. However, the late monsoon season, from September to the date the monsoon withdraws from the country, is expected to be moderate to weak, it added.

The department has also forecast that Tanintharyi Region and eastern Shan State will experience below-average rainfall in the early monsoon season, while other areas should receive about their average.

The department also warned of the possibility of isolated severe weather conditions, such as strong winds and thunder showers in the transition period of the monsoon season.

It also forecasted that three low pressure areas could be expected to form in the Bay of Bengal by the end of June, two of which could intensify into depressions.

Dr Tun Lwin, a former director general of the department, said this year’s monsoon onset would be normal when compared to the 30-year average. He said he expected the monsoon would advance into Tanintharyi Region after May 10.

“Based on the current weather situation, rainfall in the early and peak monsoon seasons should be fair but there is likely to be less rainfall in the late monsoon season,” he said.

Monsoon failure – when normal monsoon conditions abate for up to two weeks during the monsoon season – is also likely to occur at some stage.

“Severe weather conditions, such as strong winds and thunder as a result of cumulonimbus clouds should be expected in periods of monsoon failure,” he said.

He said the US-based International Research Institute (IRI) had forecast above-average rainfall for Myanmar until the end of July.

IRI forecast 25 to 40 percent above-average rainfall over that period for all areas of the country except Chin State, upper Sagaing Region, Kachin State, Kayin State and Tanintharyi Region.