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The Asian-Australian Monsoon System: Recent Evolution,

Current Status and Prediction

Update prepared byClimate Prediction Center / NCEP

September 04, 2012

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, most of India, east-central China, parts of Thailand and Cambodia and southwestern Australia had below normal rainfall. Severe shortages of monsoon rainfall exist over Gujarat, peninsular areas and northern and western parts of India. The only regions in the monsoon Asia where rainfall was above normal were northeast India, Burma, sporadically across southeastern China, the Philippines and Irian Jaya of Indonesia.

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Precip Patterns: Last 30 Days

The 30-day precipitation anomaly pattern over India and much of southeast Asia was generally above normal, particularly over northwest India. This recent abundant rain is somewhat compensating for the below normal rainfall earlier in the monsoon season. According to the India Met. Dept. (IMD) the all India Monsoon Rainfall (AIMR) from 1st June thru the 29th of August continues to be deficient by as much as 12 % from their long term normal.

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Precip Patterns: Last 7 Days

This past week, south Central India and the western Ghats regions received above normal rainfall, but northern and eastern parts of India remained deficient in rainfall amounts. Rainfall was also below normal over much of southeast Asia.

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Atmospheric Circulation

The slight anomalous troughing in the easterlies in west central India above normal in the region including Gujarat, which suffered the serious deficit of monsoon rainfall so far in the season.

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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, most of India, east-central China, parts of Thailand and Cambodia and southwestern Australia had below normal rainfall. Severe shortages of monsoon rainfall exist over Gujarat, peninsular areas and northern and western parts of India. The only regions in the monsoon Asia where rainfall was above normal were northeast India, Burma, sporadically across southeastern China, the Philippines and Irian Jaya of Indonesia. However, the 30-day precipitation anomaly pattern over India and much of southeast Asia was generally above normal, particularly over northwest India. This recent abundant rain is somewhat compensating for the below normal rainfall earlier in the monsoon season. According to the India Met. Dept. (IMD) the all India Monsoon Rainfall (AIMR) from 1st June thru the 29th of August continues to be deficient by as much as 12 % from their long term normal. This past week, south Central India and the western Ghats regions received above normal rainfall, but northern and eastern parts of India remained deficient in rainfall amounts. Rainfall was also below normal over much of southeast Asia. NCEP/GFS’s week1 and week2 forecasts and time series of the 5x5 degree grid boxes are not available due to technical difficulties associated with the move of CPC/NCEP to the new building.

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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