'It will then move southwest through Yemen as a subtropical cyclone
"Environmental conditions are generally conducive for a tropical or subtropical cyclone
to form later today or Saturday while this system moves west-northwestward to northwestward toward the Southeastern United States coast," the center's 7:45 a.m.
'Then it will move southwest through Oman as a subtropical cyclone
and northwest into Saudi Arabia and dissipate.'
Sidebar 4.2 describes a rare and interesting subtropical cyclone that developed over the southeast Pacific, a region usually not conducive to such development.
SIDEBAR 4.2: A SOUTHEAST PACIFIC BASIN SUBTROPICAL CYCLONE OFF THE CHILEAN COAST--S.
In late April, Earth Observing (EOSDIS) satellite imagery showed a cyclonic circulation in the southeastern Pacific basin that appeared to meet the definition of a subtropical cyclone. Originating from a stalled frontal zone near 25[degrees]S, 102[degrees]W the storm developed into a clearly nonfrontal system with the majority of convection initially to the southeast of low-level circulation.
da Rocha, 2013: Synoptic and dynamical analysis of subtropical cyclone Anita (2010) and its potential for tropical transition over the South Atlantic Ocean.
A., 2010: Simulations of subtropical cyclones in a baroclinic channel model.
Braun, 2012: A climatology of subtropical cyclones in the South Atlantic.
Track forecasting improvements for tropical cyclones (inclusive of subtropical cyclones
in this study) have been one of the most remarkable accomplishments in meteorology, with errors decreasing by about two-thirds in just a generation.
Classification and synoptic analysis of subtropical cyclones
within the Northeastern Atlantic Ocean.
Much of the rest of the workshop was spent discussing the details of such issues as what variables should be provided and at what frequency, how to define the beginning and end of each event, and the application of uniform conventions to such matters as conversions between maximum wind speed and central surface pressure, between 10- and 1-min sustained winds, and between gust and sustained wind (gust factors), in what units to express the variables and at what precision, consistency in the definitions of, for example, subtropical cyclones
and extratropical transitioning systems, and whether and how to include tropical cyclone-like phenomena such as medicanes and polar lows.