Wunderground.com - 5/10/13, Dr. Jeff Masters
Figure 1. Double trouble: Tropical Cyclone Jamala (lower) and Tropical Cyclone 01B (upper storm) spin on opposite sides of the Equator in this infrared satellite image taken at 12 UTC (7 am EDT) Friday May 10, 2012. Image credit: University of Wisconsin CIM
There's double trouble in the Indian Ocean today, with a pair of counter-rotating tropical cyclones spinning away on either side of the Equator. In the Southern Hemisphere, we have Tropical Cyclone Jamala, a tropical storm with 45 mph winds that is headed southwards at 3 mph. Jamala is expected to intensify into a Category 1 storm over the weekend, but is not a threat to any land areas. In the Northern Hemisphere, it's Tropical Cyclone 01B, a tropical storm with 40 mph winds that is dumping heavy rains over western Sumatra. This storm much larger and far more dangerous than its Southern Hemisphere twin brother. Cyclone 01B is under high wind shear of 20 - 30 knots, which is keeping the system disorganized, with the heaviest thunderstorms displaced from the center of rotation. However, Cyclone 01B is expected to move generally northwestwards over the next few days through the Bay of Bengal, where wind shear is lower and ocean temperatures are an exceptionally warm 31°C (88°F). This is about 1°C warmer than average for this time of year. The official forecast brings the storm to Category 1 strength before landfall occurs in Myanmar just south of the border with Bangladesh early next week. Comparative model forecasts of Cyclone 01B from the GFS, ECMWF, UKMET, GEM, NAVGEM, and FIM models show poor agreement on the intensity of Cyclone 01B, though, and it is possible that wind shear will keep the storm disorganized until landfall, with heavy rain being the main threat.
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