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The Asian-Australian Monsoon System: Recent Evolution,

Current Status and Prediction

Update prepared byClimate Prediction Center / NCEP

September 30, 2013

For more information, visit:

http://www.cpc.ncep.noaa.gov/products/Global_Monsoons/Asian_Monsoons/Asian_Monsoons.shtml

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Outline• Recent Rainfall and Current Conditions

• Monsoon Prediction

• Summary

• Climatology

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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.

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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, parts of eastern China, North and South Koreas, Japan, Philippines, Laos, and southern Vietnam.

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Precip Patterns: Last 7 Days

During this past week, an anomalous low pressure center brought heavy rainfall over Gujarat and vicinity in India. However, rainfall was below normal over much of central and southern peninsular India, Japan, and across parts of Indonesia. As of 30th of September (since 1st of June), the India Met. Dept. (IMD) has announced that the all India monsoon rainfall index measure is about (5 ?) % above long term mean (IMD website is down at the time of this writing!).

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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.

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Atmospheric Circulation

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

Week-1

Week-2

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SummaryDuring 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. 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, parts of eastern China, North and South Koreas, Japan, Philippines, Laos, and southern Vietnam.

During this past week, an anomalous low pressure center brought heavy rainfall over Gujarat and vicinity in India. However, rainfall was below normal over much of central and southern peninsular India, Japan, and across parts of Indonesia. Currently active Typhoon Wutip (cat 2) in the northern part of South China Sea on its westward track is threatening with landfall in North Vietnam and Laos. As of 30 th of September (since 1st of June) officially the end of summer monsoon rainfall over India, the India Met. Dept. (IMD) has announced that the all India monsoon rainfall index measure is about (5 ?) % above long term mean (IMD website is down at the time of this writing!). 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.

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Demise of the Asian MonsoonDemise of the Asian Monsoon

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Onset of the Australian MonsoonOnset of the Australian Monsoon

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ClimatologyClimatology