The AsianAustralian Monsoon System Recent Evolution Current Status

The Asian-Australian Monsoon System: Recent Evolution, Current Status and Prediction Update prepared by Climate Prediction Center / NCEP June 15, 2020 For more information, visit: http: //www. cpc. ncep. noaa. gov/products/Global_Monsoons/Asian_Monsoons. shtml 1

Outline • Recent Rainfall and Current Conditions • Monsoon Prediction • Summary • Climatology 2

Precip Patterns: Last 90 Days For the past 90 days, the rainfall pattern was overall near to above normal over Iran, well above normal over east central Afghanistan, much of Pakistan, and above normal over northern and central eastern India and Bangladesh. Above normal rainfall was also observed over southeastern China, across Indonesia, and somewhat near normal over southeastern Australia. Elsewhere the rainfall amounts were near to below normal, particularly southern tip of south India and South China 3 large Sea countries. Below normal rainfall deficits continue to dominate eastern Papua New Guinea, parts of northern and western Australia, particularly coastal regions of Northern Territory.

Precip Patterns: Last 30 Days For the past 30 days, rainfall pattern is characterized by above normal rainfall over Nepal, northeastern India and southeastern China, and across large parts of Indonesia. Below normal rainfall is noted over South China Sea countries. Below normal rainfall pattern is also 4 noted across southeastern Australia.

Precip Patterns: Last 7 Days In this past week, near to above normal rainfall is received over central India, and east central China. As the southwest summer monsoon has centered itself over India and southeast Asia, rainfall has pretty much receded from Australia, which has experienced deficient rainfall throughout the country so far, except along the southeast regions. It appears that the Indian monsoon advance across central India this year so far, is slightly 5 ahead of its normal advance.

Atmospheric Circulation Generally these CDAS maps are two days behind. But sometimes, as it is today, due to technical issues, these maps are further behind. 6

Rainfall Time Series over 5 x 5 lat-lon boxes The time series of precipitation over the various regions is pretty much consistent with the spatial maps shown earlier. 7

NCEP/GFS Model Forecasts Accumulated Precip. for Week 1 & Week 2 Week-1 Week-2 8

NCEP/GFS Model Forecasts Bias-Corrected Precip. Anom. for Week 1 & Week 2 Week-1 Week-2 9

Summary For the past 90 days, the rainfall pattern was overall near to above normal over Iran, well above normal over east central Afghanistan, much of Pakistan, and above normal over northern and central eastern India and Bangladesh. Above normal rainfall was also observed over southeastern China, across Indonesia, and somewhat near normal over southeastern Australia. Elsewhere the rainfall amounts were near to below normal, particularly southern tip of south India and South China Sea countries. Below normal rainfall deficits continue to dominate eastern Papua New Guinea, large parts of northern and western Australia, particularly coastal regions of Northern Territory. For the past 30 days, rainfall pattern is characterized by above normal rainfall over Nepal, northeastern India and southeastern China, and across large parts of Indonesia. Below normal rainfall is noted over South China Sea countries. Below normal rainfall pattern is also noted across southeastern Australia. In this past week, near to above normal rainfall is received over central India, and east central China. As the southwest summer monsoon has centered itself over India and southeast Asia, rainfall has pretty much receded from Australia, which has experienced deficient rainfall throughout the country so far, except along the southeast regions. It appears that the Indian monsoon advance across central India this year so far, is slightly ahead of its normal advance. For the next two weeks, the NCEP GFS model is forecasting above normal rainfall over east central and northeastern India, Bangladesh, Burma, as well as large parts of southeastern China, and over parts of Indonesian islands in the first week. Elsewhere near to below normal 10 rainfall is forecast.

Demise of the Asian Monsoon 11

Onset of the Australian Monsoon 12

Climatology 13

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