Moresby rain, last of wet season and La Nina

National, Normal

The National – Thursday, June 23, 2011

THE National Weather Service recorded 250.8mm of rain in Port Moresby and parts of Central last week.
The service said the continuous rain in most parts of the country was the last remnants of the wet season.
The highest daily rain fall was 170.4mm recorded for Port Moresby and Central last Tuesday, with the lowest being 0.2mm last Friday.
Senior forecaster Konney Nato said the normal wet season from November to March had extended to April and May as experienced last week because of the complexity of the La Nina period.
“The dry season has now started according to the weather calendar but predictions are above normal rainfall condition from June to September.
“This means it will not be dry throughout but there will be slight rainfall during this dry season,” Nato said.
“There will be dry conditions but we will be expecting some precipitation in between especially confined to the evenings.
“We use the models to predict the weather conditions, and according to the PNG model, Australian Climate Model, Asia Pacific Climate Centre and the Pacific Island Climate Update, there will be above normal rainfall conditions,” Nato said.
He said the main cause was the sea surface temperature, which was warm over the PNG maritime areas, especially the New Guinea Islands region.
“In the previous dry seasons, the warm temperature receded quickly to the eastern and western Pacific areas.
“But it’s taking longer as a result of the unpredictability of the climate and La Nina,” Nato said.
He said the variables they were collecting in weather stations like rainfall, wind and temperature varied in different locations.
“A meteorological station can give an accurate observed region for the variables up to approximately only 10km radius.
“This suggests that we need more observation stations to collect more data for all areas of the country.
“An example can be that of the 10km radius.
“It could be raining in the Motuan village of Porebada, Central, to the west on the coast but in 7-Mile, where the weather office is, it could be dry.
“This is because the 10km radius cannot pick up the variable accurately,” he said.