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The Asian-Australian Monsoon System: Recent Evolution, Current Status and Prediction. Update prepared by Climate Prediction Center / NCEP April 05, 2010. For more information, visit: http://www.cpc.ncep.noaa.gov/products/Global_Monsoons/Asian_Monsoons/Asian_Monsoons.shtml. Outline.
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The Asian-Australian Monsoon System: Recent Evolution, Current Status and Prediction Update prepared by Climate Prediction Center / NCEP April 05, 2010 For more information, visit:http://www.cpc.ncep.noaa.gov/products/Global_Monsoons/Asian_Monsoons/Asian_Monsoons.shtml
Outline • Recent Evolution and Current Conditions • Monsoon Prediction • Summary • Climatology
Precip Patterns: Last 90 Days During the past 90 days, below-average precipitation was observed over the Philippine Sea, western Australia, tropical southeastern Indian Ocean, and Madagascar. On the other hand, above-average precipitation appeared over part of East Asia, much of the tropical central Indian Ocean, the Arafura Sea, eastern Australia, and equatorial western Pacific Ocean.
Precip Patterns: Last 30 Days During the past 30 days, below-average precipitation was observed over southern Asia, Middle East, the western Pacific, western Australia, part of subtropical Southern Indian Ocean, and western Asian. Above-average precipitation was seen over East Asia, and part of tropical-subtropical southern Indian Ocean.
Precip Patterns: Last 5 Days Above-average precipitation was observed over northern Australia, part of south-eastern Asia, and the tropical western Pacific. Below-normal precipitation appeared over eastern Asian, Southern Indian Ocean, and Madagascar.
Atmospheric Circulation The lower-tropospheric southwesterly flow was over south-western China. Strong easterly anomaly over northern Australia was related to the tropical storm there.
NCEP/GFS Model Forecasts Bias-Corrected Precip. Anom. for Weak 1 & Week 2 Week-1 Week-2
Prediction of East Asia – NW Pacific Monsoon Upper panel: East Asia – Western North Pacific (EAWNP) monsoon index (Wang et al. 2008) defined as U850 (5-15ºN, 40-80ºE) – U850 (20-30ºN, 70-90ºE). Positive (negative) values indicate strong (weak) than normal monsoon. The NCEP Global Forecast System predicts that, in the next two weeks, the monsoon circulation over Southeast Asia and northwestern Pacific will fluctuate around normal. Lower panel: Correlation between rainfall and East Asia – Western North Pacific monsoon index (Wang et al. 2008; shading) and regression of 850-mb winds on the monsoon index (vectors) for March. Green (brown) shading indicates increase (decrease) in rainfall associated with strong monsoon.
Prediction of Australian Monsoon Upper panel: Australian monsoon index (Hung and Yanai 2004) defined as U850 averaged over 2.5ºS-15ºS, 110-150ºE. Positive (negative) values indicate strong (weak) than normal monsoon. The NCEP Global Forecast System predicts that, in the next two weeks, the Australian monsoon circulation will continue to be weaker than normal. Lower panel: Correlation between rainfall and Australian monsoon index (Hung and Yanai 2004; shading) and regression of 850-mb winds on the monsoon index (vectors) for March. Green (brown) shading indicates increase (decrease) in rainfall associated with strong monsoon.
Summary • During the last 5 days, above-average precipitation was observed over northern Australia, part of south-eastern Asia, and the tropical western Pacific. Below-normal precipitation appeared over eastern Asian, Southern Indian Ocean, and Madagascar. • The NCEP Global Forecast System predicts that, in the next two weeks, the Australian monsoon circulation will keep to above normal.
