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The passage of the MJO event left behind twin cyclones in either side of the equator, where the northern developed into TC Roanu.
Below are figures from http://meteo.fmf.uni-lj.si/MODES showing the flow on 850 hPa decomposed into balanced (Rossby) modes, unbalanced (ID) modes and Kelvin modes for the 15 May 00z analysis.
3. Predictability
3.1 Data assimilation
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