Tropical Cyclone Discussion
655 WTPZ42 KNHC 291438 TCDEP2 Tropical Storm Lowell Discussion Number 8 NWS National Hurricane Center Miami FL EP122026 500 AM HST Sat Aug 29 2026 Lowell is slightly better organized than it was at this time yesterday, as the low-level center is now beneath the convective overcast. However, satellite imagery suggests that the mid-level center is still displaced west of the low-level center due to ongoing easterly shear. Overnight scatterometer data suggest that the maximum winds were 35-40 kt, so the initial intensity remains 40 kt. Lowell continues moving westward or 280/7 kt. A low- to mid-level ridge is forecast to strengthen north of the cyclone during the next couple of days, which should cause Lowell to continue westward with some a gradual increase in forward speed. This general westward motion is expected to continue through the weekend and into early next week. After that, the guidance becomes quite divergent in both direction and speed due to the potential effects of Tropical Storm Karina on Lowell's steering flow. By 120 h, the Google Deepmind Ensemble mean shows a continued westward motion, the GFS, UKMET, and the regional hurricane models show a slower motion toward the northwest, the ECMWF shows a slow motion toward the west, and the Canadian model turns the cyclone northeastward. The new track forecast lies between the Google Deepmind and the GFS cluster of models, and it is similar to the previous forecast. The current easterly shear should continue for another 18-24 h before diminishing. The shear, along with mid- to upper-level dry air seen in water vapor imagery just north of the cyclone, should result in slow strengthening through 24 h. After that conditions become more favorable, and the intensity forecast shows a faster rate of development. By the end of the forecast period, the intensity forecast becomes more uncertain due to Lowell's potential interaction with Karina. As noted before, a faster westward track would likely keep the cyclones sufficiently separated and allow Lowell to continue strengthening, while a slower solution could expose Lowell to stronger shear associated with outflow from Karina. The latest NHC intensity forecast has only minor tweaks from the previous forecast, and it lies near the middle of a guidance envelope that has a significant spread. FORECAST POSITIONS AND MAX WINDS INIT 29/1500Z 12.8N 135.7W 40 KT 45 MPH 12H 30/0000Z 12.8N 137.3W 40 KT 45 MPH 24H 30/1200Z 12.8N 139.7W 45 KT 50 MPH 36H 31/0000Z 12.8N 141.8W 50 KT 60 MPH 48H 31/1200Z 12.9N 143.6W 60 KT 70 MPH 60H 01/0000Z 13.0N 145.2W 70 KT 80 MPH 72H 01/1200Z 13.1N 146.9W 80 KT 90 MPH 96H 02/1200Z 13.4N 149.4W 90 KT 105 MPH 120H 03/1200Z 13.8N 151.5W 95 KT 110 MPH