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 September 16, 2013 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 During the past 90 days, rainfall has been generally above normal over much of central and northern India, Burma, Indonesia and Philippines, but below normal especially over parts of eastern China, Japan, South Korea, Thailand, Cambodia, Laos, and Vietnam. 3

Precip Patterns: Last 30 Days The 30 -day anomalous rainfall pattern over monsoon Asia is beginning to look somewhat differently from the 90 -day pattern. Some dryness is beginning to develop along central and western India, Laos, Vietnam and Cambodia. 4

Precip Patterns: Last 7 Days During this past week, the monsoon rains have been highly deficient over much of northern and central India, southern peninsular India received more than normal rainfall. In fact, the state of Tamilnadu in southeast India, whose primary rainfall season is the northeast monsoon, had one of its best rainfall amounts in many years from this southwest monsoon. Monsoon has withdrawn from northwestern and north central India. As of 16 th of September (since 1 st of June), the India Met. Dept. (IMD) has announced that the all India monsoon rainfall index measure is only about 4% above long term mean. The large rainfall excess that existed 5 over all of India (except the northeast) earlier has shrunk considerably.

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. 6

Atmospheric Circulation 7

NCEP/GFS Model Forecasts Bias-Corrected Precip. Anom. for Weak 1 & Week 2 Week-1 Week-2 8

Summary During the past 90 days, rainfall has been generally above normal over much of central and northern India, Burma, Indonesia and Philippines, but below normal especially over parts of eastern China, Japan, South Korea, Thailand, Cambodia, Laos, and Vietnam. The 30 -day anomalous rainfall pattern over monsoon Asia is beginning to look somewhat differently from the 90 -day pattern. Some dryness is beginning to develop along central and western India, Laos, Vietnam and Cambodia. During this past week, the monsoon rains have been highly deficient over much of northern and central India, southern peninsular India received more than normal rainfall. In fact, the state of Tamilnadu in southeast India, whose primary rainfall season is the northeast monsoon, had one of its best rainfall totals in many years from this southwest monsoon. Monsoon has withdrawn from northwestern and north central India. As of 16 th of September (since 1 st of June), the India Met. Dept. (IMD) has announced that the all India monsoon rainfall index measure is only about 4% above long term mean. The large rainfall excess that existed earlier over all of India (except the northeast) has now shrunk considerably. For the next two weeks, the NCEP GFS model predicts that southwest monsoon will be in its withdrawal phase from northern India and parts of China. 9

Demise of the Asian Monsoon 10

Onset of the Australian Monsoon 11

Climatology 12