Tropical Cyclone 20P Forms East of the Cook Islands
Tropical Cyclone 20P, located approximately 95 nm east of Rarotonga, Cook Islands, has tracked southward at 6 knots over the past 6 hours.
Animated infrared satellite imagery and an SSMI image indicate a consolidating low-level circulation center (LLCC) with improved convective banding wrapping into the southeast quadrant of the system.
The SSMI 37 ghz image supports a developing LLCC with a more defined center.
Recent scatterometer, in general, showed 25-30 knot unflagged winds. However, Dvorak estimates have increased to 30-35 knots based on the improved structure near the center.
The LLCC is situated under an upper-level anticyclone with good poleward outflow enhanced by a deep shortwave trough west of the system (along 165W) and an anticyclone near 28S 147W.
The system is tracking along the western periphery of a poleward oriented low-level subtropical ridge and is predicted to continue tracking southward through the forecast period.
TC20P is expected to intensify slightly over the next 12 hours but should weaken quickly as the aforementioned upper-level trough shifts east and disrupts outflow. Additionally, cooler SST will weaken the system below 35 knots after TAU 36 leading to dissipation over water.
Maximum significant wave height at 110600z is 8 feet.