Tropical Cyclone Imelda (21S) Northeast of Madagascar – April 11th, 201311.1S 56.2E
Tropical Cyclone Imelda (TC 21S) located approximately 515 nm north-northeast of La Reunion, has tracked southward at 02 knots over the past six hours.
Animated multispectral satellite imagery depicts tightly curved spiral banding wrapping into a low level circulation center. An SSMIS 37ghz microwave image depicts deep convection favoring the eastern quadrants in response to slightly increased vertical wind shear (VWS), however the center remains well defined.
The system is now quasi-stationary as the steering ridge to the southeast is weakening and becoming re- oriented in response to an approaching deep-layer trough (DLT). The initial position is extrapolated from the aforementioned SSMIS image with fair confidence.
The initial intensity is assessed at 75 knots based on a range of Dvorak current intensity estimates from 65 to 77 knots. Upper level analysis indicates the system has a point source overhead providing moderate radial outflow, with VWS increasing slightly to 10 to 15 knots.