Understanding Weather – not predicting – 22 February 2013

What happened?
The complexity of weather gained some attention and, just to underscore it, we have been exposed to more of its intricacies. The focus is on the rather distant Mozambique Channel where anomalous warmer sea surface temperatures have held sway for some weeks. Tropical Cyclones tend to develop over such warmer water.
Assisting this eventuality, the past few weeks there have been limited anticyclonic cores passing far enough south of the Cape to first provide days of Southeasters at the Cape and second to establish a core to the south of the Channel ensuring a cooler airflow above this stretch of water while advecting a deep air flow into the sub-continent towards the persistent heat low.
The prevailing pattern is much more representative of a winter scenario, it is inconsistent with the patterns evident above both the Indian and Pacific Oceans.
This complex variation is not readily explained, one effect was the rapid development of Tropical Cyclone Haruna above mid-Channel, with another complexity: its shallowness.
Such storm cores dominate the airmasses from surface to levels as high as 200 or 150 hPa (40 to 45000 feet), but not this one!