Tropical Cyclone Discussion
520 WTNT42 KNHC 250842 TCDAT2 Tropical Storm Gonzalo Discussion Number 2 NWS National Hurricane Center Miami FL AL072026 800 AM CVT Fri Sep 25 2026 Gonzalo remains an asymmetric tropical storm, with wind shear displacing the deep convection over the eastern and southern portions of the center. Satellite intensity estimates from TAFB and UW-CIMSS are around 35-40 kt. Given the earlier scatterometer data depicting 40 kt and a steady satellite appearance, the initial intensity for this advisory is held at 40 kt. The initial motion remains north-northwestward at 340/8 kt. The storm is expected to continue moving north-northwestward during the next couple of days, steered by the flow of a deep mid-level trough over the eastern Atlantic. As the trough lifts northwestward later in the forecast period, the steering currents will become very weak, and Gonzalo is forecast to slow down and meander over the eastern Atlantic. On the forecast track, the center will pass near or over portions of the Cabo Verde Islands today and tonight. The official NHC track forecast is lies between the HCCA corrected consensus and GDMI aids. Gonzalo has about 12 to 18 hours within a marginally conducive environment for some strengthening, with sea surface temperatures near 27-28 deg C. After that time, vertical wind shear is forecast to increase, becoming fairly strong by day 2. Along the forecast track, sea surface temperatures will also cool, and mid-level relative humidity values will begin to drop into the 50, and then 40 percent range. The NHC intensity forecast is similar to the previous advisory. Global model-simulated infrared satellite imagery depicts Gonzalo becoming devoid of deep convection in about 2 to 3 days. Thus, the forecast shows the system becoming a post-tropical remnant low at that time, and it is expected to remain a remnant low through day 5. Key Messages: 1. Tropical storm conditions are expected to spread across portions of the Cabo Verde Islands, where a Tropical Storm Warning is in effect, today and will continue through tonight. 2. Heavy rains from Gonzalo could affect the eastern islands of Cabo Verde and the western coast of Africa between Guinea-Bissau to Senegal today through Saturday. Areas of flash flooding will be possible along the western coast of Africa with some isolated flash flood concerns for the eastern islands of Cabo Verde. FORECAST POSITIONS AND MAX WINDS INIT 25/0900Z 14.2N 22.4W 40 KT 45 MPH 12H 25/1800Z 15.4N 22.8W 45 KT 50 MPH 24H 26/0600Z 17.0N 23.2W 45 KT 50 MPH 36H 26/1800Z 18.5N 23.7W 35 KT 40 MPH 48H 27/0600Z 19.8N 24.2W 30 KT 35 MPH 60H 27/1800Z 20.5N 24.3W 25 KT 30 MPH...POST-TROP/REMNT LOW 72H 28/0600Z 21.0N 24.4W 20 KT 25 MPH...POST-TROP/REMNT LOW 96H 29/0600Z 22.0N 24.5W 20 KT 25 MPH...POST-TROP/REMNT LOW 120H 30/0600Z 22.2N 25.7W 20 KT 25 MPH...POST-TROP/REMNT LOW