Issued at 500 AM AST Wed Aug 27 2025
524 WTNT41 KNHC 270840 TCDAT1 Tropical Storm Fernand Discussion Number 15 NWS National Hurricane Center Miami FL AL062025 500 AM AST Wed Aug 27 2025 Fernand continues to sputter along as a lopsided tropical storm, producing deep convection primarily along its southern semicircle. This convective activity has not been particularly well organized on either geostationary or microwave satellite images. In fact, overnight Proxy-Vis satellite imagery suggests this convective activity has been stretching the low-level vortex of the tropical cyclone, making it somewhat elongated. Satellite intensity estimates this morning have a wide range between 30 kt to 51 kt. Out of deference to the earlier scatterometer data, Fernand's initial intensity remains 40 kt this advisory, which is also roughly in the middle of the various estimates. The ongoing deep convection appears to be impacting Fernand's short-term motion, which is east of the prior forecast track, moving at an estimated 080/10 kt. This motion could persist a little longer given the tropical cyclone's ongoing convective asymmetry. Still, Fernand is expected to resume an accelerating east-northeastward motion later today, caught up in deep-layer southwesterly flow downstream of a large mid-latitude trough over eastern North America. Given the short-term motion, the track guidance has shifted a little east of the prior cycle, and the latest NHC track forecast has elected to go along the eastern edge of this track envelope, close to the latest HCCA and EC-AIFS solutions. The ongoing deep convection has also bought Fernand a little more time as a tropical cyclone, though probably only another 24 hours since the cyclone will soon cross a sharp sea-surface temperature gradient as it passes the north wall of the Gulf Stream. The NHC intensity forecast shows Fernand becoming post-tropical in about 24 h, and opening up into a trough and dissipating in 60 h. FORECAST POSITIONS AND MAX WINDS INIT 27/0900Z 38.3N 50.8W 40 KT 45 MPH 12H 27/1800Z 39.3N 48.2W 40 KT 45 MPH 24H 28/0600Z 41.3N 44.0W 35 KT 40 MPH...POST-TROPICAL 36H 28/1800Z 43.3N 38.3W 35 KT 40 MPH...POST-TROPICAL 48H 29/0600Z 45.2N 30.9W 30 KT 35 MPH...POST-TROP/REMNT LOW 60H 29/1800Z...DISSIPATED $$ Forecaster Papin