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The Asian-Australian Monsoon System: Recent Evolution,

Current Status and Prediction

Update prepared byClimate Prediction Center / NCEP

December 10, 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, rainfall is slightly above normal near the Gangetic plains in north India, southeastern China, Korea, Japan, and sporadically across parts of southeast Asia as well as over western Australia. However, over southern central and southern peninsular India (in areas under the influence of NE monsoon), Laos, Thailand, and over eastern half of Australia, the rainfall is below normal.

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Precip Patterns: Last 30 Days

The 30-day precipitation continues to be considerably above normal over southeast China and below normal over southeastern India. From the 1st of October thru the 5th of December, India Met. Dept. is reporting that the NE monsoon rainfall amounts over India is about 19 % below their long term normal. The Northeast Monsoon over southern India has so far turned out to be very weak.

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Precip Patterns: Last 7 Days

One week NCEP GFS model prediction (bottom left) of rainfall over south/southeast Asia continues to verify fairly accurately (top right) week after week.

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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 is slightly above normal near the Gangetic plains in north India, southeastern China, Korea, Japan, and sporadically across parts of southeast Asia as well as over western Australia. However, over southern central and southern peninsular India (in areas under the influence of NE monsoon), Laos, Thailand, and over eastern half of Australia, the rainfall is below normal. The 30-day precipitation continues to be considerably above normal over southeast China and below normal over southeastern India. From the 1st of October thru the 5th of December, India Met. Dept. is reporting that the NE monsoon rainfall amounts over India is about 19 % below their long term normal. The Northeast Monsoon over southern India has so far turned out to be very weak. From the 1st of October thru the 5th of December, India Met. Dept. is reporting that the NE monsoon rainfall amounts over India is about 19 % below their long term normal. The Northeast Monsoon over southern India has so far continues to remain relatively weak.

For the upcoming couple of weeks the NCEP GFS model continues to predict below normal amounts over southern India and the model has resumed predicting above normal rainfall over southeastern China. In a new feature in the upcoming weeks, the model now predicts above normal rainfall over northern India near Kashmir and adjoining Pakistan region as well as over parts of western Australia.

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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