Tropical Cyclone Formation Alert in Pacific Ocean
An area of convection is now located approximately 240 nautical miles northwest of Rarotonga, in the Cook Islands.
The formation of a significant tropical cyclone is possible within 180 nautical miles either side of a line from 18.1S 163.5W to 23.9S 160.9W within the next 06 to 24 hours.
Winds in the area are estimated to be 25 to 30 knots. METSAT imagery indicates that a circulation center is located near 18.9S 163.2W. The system is moving southward at 6 knots.
Animated infrared satellite imagery and a METOP-A image indicate a rapidly consolidating low-level circulation center (LLCC) with multiple deep convective bands spiraling into the center.
This system, like TC 20p, is developing from the mid-levels down to the surface. However, unlike 20p, this system has better radial outflow with more rapidly improving convective banding evident at this early stage of development.
Despite surface development lagging slightly behind convective organization, scatterometer data has increasingly supported a strengthening LLCC. A partial ASCAT image shows 25-30 knot northerly flow over the eastern semi-circle.
The overall environment is very favorable for further development. Upper-level analysis and animated water
vapor imagery indicate an anticyclone over the LLCC with very good poleward outflow enhanced by two upper-level lows (southwest and southeast of the system), as well as excellent equatorward outflow enhanced by strong cross-equatorial flow.
The SST of 29C, ocean heat content and a deep moisture envelope support continued consolidation. Maximum sustained surface winds are estimated at 25 to 30 knots. Minimum sea level pressure is estimated to be near 1000 mb.
Based on the favorable environment characterized by excellent outflow and a rapidly organizing LLCC, the potential for the development of a significant tropical cyclone within the next 24 hours is good.