Tropical Cyclone Discussion
Issued by NWS
Issued by NWS
734 WTPA44 PHFO 100851 TCDCP4 Tropical Storm Lowell Discussion Number 57 NWS Central Pacific Hurricane Center Honolulu HI EP122026 Issued by NWS National Hurricane Center Miami FL 1100 PM HST Wed Sep 09 2026 Proxy-visible and infrared satellite images show that Lowell is producing minimal convection on the northern side of the storm. The center of the cyclone is exposed and based on water vapor imagery, plenty of dry air has made its way to the center. Nonetheless, a recent ASCAT pass showed a large area of 50-53 kt vectors to the northwest of the center, indicating that Lowell was stronger than previously estimated. Based on this data, the initial intensity has been set to 55 kt. The storm is continuing to move to the west around 280 degrees at 12 kt. Currently the cyclone is being guided by a low- to mid-level ridge located to the north, which should keep it on this westward heading for the next couple of days. After that, a mid- to upper-level trough to the northwest is expected to cutoff and become the main steering flow for Lowell. This should result in a northerly turn for the storm as it interacts with the cutoff low around 36-48 h. As the cutoff low moves off to the east, Lowell should take up a more westward motion for a short period of time. Then, once the cutoff low pulls away completely, the shallow circulation of Lowell will likely be stuck between two low-level ridges, thus leaving the storm to drift slowly off to the south as a remnant low. The current NHC track forecast is very close to the previous one, however there were some small nudges made to the new track forecast after 36 h. This prediction is close to the most recent Google DeepMind (GDMI) and HFIP Corrected Consensus Approach (HCCA) aids. The cyclone is expected to remain in a hostile environment with moderate wind shear, plenty of dry air, and marginal SSTs. Therefore, a gradual weakening trend is expected for the next 24 h. Based on the simulated satellite imagery from the GFS and ECMWF, Lowell could lack enough convection to be considered a tropical cyclone. However, some positive interaction with the previously mentioned cutoff low could foster the development of new convection, which in turn could allow for Lowell to maintain its intensity through baroclinic processes. After 60-72 h, the cyclone will be on the subsident side of the cutoff low, which will likely lead to the storm becoming post-tropical as the convection dissipates. It should be noted that there is a fair chance that the convection fails to regenerate due to the dry air and shear, and thus Lowell could become post-tropical sooner than forecast. The updated NHC intensity forecast shows no net intensity change between 24-72 h, although small fluctuations could occur as described above. KEY MESSAGES: 1. Post-storm safety: Follow advice of local officials and avoid areas of downed power lines and flooding. Ensure generators are properly ventilated and placed outside at least 20 feet away from dwellings and garages to avoid carbon monoxide poisoning. During clean up, be careful when using chainsaws and power tools. Drink plenty of water to avoid heat exhaustion. FORECAST POSITIONS AND MAX WINDS INIT 10/0900Z 29.2N 166.2W 55 KT 65 MPH 12H 10/1800Z 29.2N 168.2W 45 KT 50 MPH 24H 11/0600Z 29.3N 170.2W 40 KT 45 MPH 36H 11/1800Z 30.1N 171.6W 40 KT 45 MPH 48H 12/0600Z 31.4N 172.1W 40 KT 45 MPH 60H 12/1800Z 33.0N 172.8W 40 KT 45 MPH 72H 13/0600Z 33.4N 173.9W 40 KT 45 MPH 96H 14/0600Z 32.8N 175.1W 30 KT 35 MPH...POST-TROP/REMNT LOW 120H 15/0600Z 31.4N 175.0W 25 KT 30 MPH...POST-TROP/REMNT LOW $$ Forecaster Katz/Reinhart