Issued at 500 PM AST Mon Oct 13 2025
001 WTNT42 KNHC 132035 TCDAT2 Tropical Storm Lorenzo Discussion Number 3 NWS National Hurricane Center Miami FL AL122025 500 PM AST Mon Oct 13 2025 A mid- to upper-level low to the west of Lorenzo is producing strong west-southwesterly shear, causing the low-level center to be mostly exposed to the west of the main area of deep convection. The initial intensity is held at 45 kt based on the earlier ASCAT data and a T3.0 Dvorak classification from TAFB. The scatterometer data is also the basis for the initial 34-kt wind radii, which shows the tropical-storm-force winds mostly limited to the eastern half of the storm. Lorenzo is moving northwestward at 10 kt, and that motion should continue for about another day. However, by late Tuesday, a turn to the north is forecast as a weakness develops in the subtropical ridge over the central Atlantic. The storm is then expected to turn northeastward later in the week as a large-scale mid- to upper-level trough approaches from the west. Most of the models show this trough cutting off, causing Lorenzo to slow down and turn eastward or southeastward over the weekend. The NHC track forecast is generally similar to the previous one and on the right side of the guidance envelope, in best agreement with HCCA. Regardless of the details, Lorenzo is not expected to be near land during the next several days. The strong shear over Lorenzo is likely to let up during the next few days, but the models also show some dry air entraining into the circulation. In fact, some of the global models show Lorenzo remaining lopsided and even opening up into a trough. The NHC intensity forecast shows some strengthening, but this is of low confidence as there is some possibility that Lorenzo succumbs to the unfavorable environmental conditions. This prediction is a little lower than the previous one, but remains near the high end of the model guidance. FORECAST POSITIONS AND MAX WINDS INIT 13/2100Z 15.2N 41.7W 45 KT 50 MPH 12H 14/0600Z 16.2N 43.1W 45 KT 50 MPH 24H 14/1800Z 17.8N 44.3W 45 KT 50 MPH 36H 15/0600Z 20.0N 44.7W 45 KT 50 MPH 48H 15/1800Z 22.6N 43.6W 45 KT 50 MPH 60H 16/0600Z 25.3N 41.6W 50 KT 60 MPH 72H 16/1800Z 28.2N 38.3W 55 KT 65 MPH 96H 17/1800Z 31.4N 31.4W 50 KT 60 MPH 120H 18/1800Z 30.1N 29.2W 45 KT 50 MPH $$ Forecaster Cangialosi
NHC Atlantic
