Tropical Storm Iba Discussion Number 20

Wiki-Hurricanes Forecast Center

12:00 PM AST Thu Mar 28 2019

Despite the late night heroics from Iba to resurge back to a tropical storm, there is scarcely any organized convection to speak of this morning. The low-level vortex which once fueled the rare South Atlantic tropical cyclone is now a rather elongated swirl of stratocumulus and cumulus cloud lines, and not particularly organized. Describing the system as a tropical cyclone at this point requires some creative license, but scatterometer data depicted at least tenative cyclonic organization. Dvorak satellite estimates are probably not very effective at this point given the structure and its embedding within a complicating windfield. The system has clearly weakened and currently looks nothing like an organized tropical cyclone, but despite the abject organization SSM/I surface wind data valid 8z suggests keeping the system at tropical storm intensity with winds of 35 kt.

Iba is not an organized system, and without much convection dissipation seems likely as it is stretched out in a developing baroclinic cyclone in an area of increased dry air and wind shear. Despite dissipation being depicted within 24 hours... this forecast could still be quite generous.


INIT 28/1500Z 35 KT 40 MPH

12H 29/0000Z 30 KT 35 MPH...POST-TROP/REMNT LOW

24H 29/1800Z...DISSIPATED