9545Central North Pacific Tropical Depression Iona Discussion Number 24
WTPA41 PHFO 020249 TCDCP1
Tropical Depression Iona Discussion Number 24 NWS Central Pacific Hurricane Center Honolulu HI CP012025 Issued by NWS National Hurricane Center Miami FL 500 PM HST Fri Aug 01 2025
Satellite imagery indicates that convection associated with Iona remains fragmented and disorganized, with the low-level circulation becoming increasingly broad and diffuse under persistent west-northwest shear. The center is exposed and becoming less defined, and a recent ASCAT pass detected peak winds of only around 25 kt in the northeastern quadrant. Subjective Dvorak current intensity estimates from SAB, HFO, and JTWC ranged from 1.5/25 kt to 2.5/35 kt. Based on these data and the degraded satellite appearance, the initial intensity is lowered to 30 kt.
The initial motion is estimated at 295/15 kt. Iona is expected to continue west-northwestward through the weekend while gradually slowing, steered by the southern flank of a low- to mid-level subtropical ridge to the north. A northwestward turn remains likely by late this weekend or early next week as the system approaches a weakness in the ridge. The latest track forecast remains similar to the previous advisory and is close to the consensus aids, with only minor adjustments.
Given the increasingly degraded structure of Iona and the lack of deep convection, little to no reorganization is anticipated. Persistent westerly shear, interaction with an upper-level trough, and the intrusion of mid- to upper-level dry air should continue to inhibit strengthening. While most dynamical model guidance depicts Iona gradually opening into a trough by early next week, the current disorganized state suggests that degeneration into a remnant low or trough could occur at any time over the weekend. The updated forecast maintains Iona as a tropical cyclone briefly, but the system is expected to dissipate by 72 hours or sooner.
This is the last advisory issued by the Central Pacific Hurricane Center on this system. Future advisories will be issued by RSMC Tokyo, Japan. Advisories issued by RSMC Tokyo are found on the web at:
For U.S. interests, see advisories issued by the Joint Typhoon Warning Center (JTWC) in Honolulu, Hawaii. Advisories issued by JTWC can be found on the web at:
Note: This service is not intended for secure transactions such as banking, social media, email, or purchasing. Use at your own risk. We assume no liability whatsoever for broken pages.