1 The Asian-Australian Monsoon System: Recent Evolution, Current Status and Prediction Update prepared by Climate Prediction Center / NCEP October 7, 2013 For more information, visit:

2 Outline Recent Rainfall and Current Conditions Monsoon Prediction Summary Climatology

3 Precip Patterns: Last 90 Days During the past 90 days, rainfall has been generally above normal over much India, Burma, Thailand, Indonesia and Philippines, but below normal especially over parts of eastern China, Japan, South Korea, Malaysia, Laos, and Vietnam. With monsoon rains still continuing across central and northern India, combined with an early start by as much as a month in northwest India, this year’s southwest summer monsoon rainfall season over India is probably one of the longest (normal ~ 85 days) in recent decades.

4 Precip Patterns: Last 30 Days The 30-day anomalous rainfall pattern over monsoon Asia is slightly differently from the 90-day pattern. Some dryness is beginning to develop along central and western India, parts of eastern China, Indonesia, North and South Koreas, Japan, and Philippines.

5 Precip Patterns: Last 7 Days During this past week, an anomalous low pressure center brought heavy rainfall across central India. However, rainfall was below normal over much of southern peninsular India, Japan, and across parts of Indonesia.

6 Rainfall Time Series over 5x5 lat-lon boxes The time series of precipitation over the various regions is pretty much consistent with the spatial maps shown earlier.

7 Atmospheric Circulation

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

9 Summary During the past 90 days, rainfall has been generally above normal over much India, Burma, Thailand, Indonesia and Philippines, but below normal especially over parts of eastern China, Japan, South Korea, Malaysia, Laos, and Vietnam. With monsoon rains still continuing across central and northern India, combined with an early start by as much as a month in northwest India, this year’s southwest summer monsoon rainfall season over India is probably one of the longest (normal ~ 85 days) in recent decades. The 30-day anomalous rainfall pattern over monsoon Asia is slightly differently from the 90-day pattern. Some dryness is beginning to develop along central and western India, parts of eastern China, Indonesia, North and South Koreas, Japan, and Philippines. During this past week, an anomalous low pressure center brought heavy rainfall across central India. However, rainfall was below normal over much of southern peninsular India, Japan, and across parts of Indonesia. As it was for the predictions made last week, for the next two weeks, it is interesting to note that the NCEP GFS model still predicts that the rainfall will continue to be above normal over central and northern India, but below normal over much of eastern China.

10 Demise of the Asian Monsoon

11 Onset of the Australian Monsoon

12 Climatology