Tropical Storm Norbert Discussion Number 18

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Tropical Storm Norbert Discussion Number 18 NWS National Hurricane Center Miami FL EP142026 500 PM HST Sun Sep 13 2026 Recent satellite imagery indicates that moderate vertical wind shear continues to displace any deep convection east of Norbert's center. Earlier ASCAT-A and ASCAT-B scatterometer passes depicted an asymmetric wind field, with peak winds near 40 kt north of the center. Given these data and Norbert's limited convection, the initial intensity is held at 40 kt. The initial motion is estimated to be 290/12 kt. The storm is expected to move west-northwestward to westward as it remains south of a low- to mid-level subtropical ridge. The track guidance continues to show good agreement on the general heading for this storm through the forecast period. The current NHC track forecast is largely unchanged from the previous advisory, and remains close to the corrected multi-model consensus (HCCA) and the Google DeepMind ensemble mean. While some fluctuations in intensity remain possible in the next 12 h or so, Norbert is forecast to begin a weakening trend that should persist through the forecast period. The cyclone continues to contend with moderate westerly to west-northwesterly vertical wind shear and SHIPS guidance is projecting the shear to gradually increase after 12-24 h. Simulated GFS and ECMWF satellite imagery show Norbert struggling to generate any deep convection by 48 h. Therefore, Norbert is expected to degenerate into a post-tropical remnant low around Tuesday, then dissipate by Wednesday. The current NHC intensity forecast remains in line with the corrected multi-model consensus (HCCA) guidance, which follows the previous advisory. FORECAST POSITIONS AND MAX WINDS INIT 14/0300Z 19.2N 135.3W 40 KT 45 MPH 12H 14/1200Z 19.5N 137.2W 40 KT 45 MPH 24H 15/0000Z 20.0N 139.8W 35 KT 40 MPH 36H 15/1200Z 20.4N 142.5W 35 KT 40 MPH 48H 16/0000Z 20.6N 145.2W 30 KT 35 MPH...POST-TROP/REMNT LOW 60H 16/1200Z...DISSIPATED