Tropical Storm Fay Forecast Discussion
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402 WTNT41 KNHC 240238 TCDAT1 Tropical Storm Fay Discussion Number 16 NWS National Hurricane Center Miami FL AL062026 300 AM GMT Thu Sep 24 2026 Deep convection has persisted since the previous advisory, especially to the north and northeast of the surface center. Recent microwave and geostationary satellite data indicate fairly good confidence that the center is near the southern or southwestern edge of the convection. The latest TAFB Dvorak intensity estimate is 2.5/35 kt and recent objective intensity estimates from UW-CIMSS range from 33-42 kt. A pair of ASCAT passes from around 23/2300 UTC showed several reliable 32 kt wind vectors. Given the low bias of the ASCAT instrument due to its resolution, the initial intensity is raised to 35 kt, in agreement with the TAFB estimate, making Fay a tropical storm again. The initial motion is estimated to be west-southwestward, or 250 degrees at 8 kt. Fay is expected to continue moving generally westward for the next few days as it is steered by a narrow low- to mid-level ridge to its north, although a deceleration is expected in a couple of days as steering currents weaken. The NHC forecast is very similar to the previous one, and is fairly close to, but slightly faster toward the west than, the latest GDMI and HCCA. Confidence in the NHC track forecast appears to be above average due to good agreement among the track models. Fay is forecast to remain over warm water and within a weak vertical wind shear environment for another 36 hours, but the dry airmass that Fay is embedded in, with mid-level relative humidity values between 30 and 40 percent, should prevent significant strengthening. The NHC forecast shows little change in strength while the shear remains weak. By 48 hours, increasing northeasterly vertical wind shear should work to induce gradual weakening. The NHC forecast is a little higher than the previous one, in that it shows a more gradual weakening in the 36 to 72 hour period. The NHC forecast is near the middle of the guidance envelope, and forecast confidence is medium to high. No changes have been made to the timing of post-tropical transition or dissipation, but it should be noted that the UKMET and Canadian models hold onto the low a bit longer than indicated in the NHC forecast. FORECAST POSITIONS AND MAX WINDS INIT 24/0300Z 29.8N 40.0W 35 KT 40 MPH 12H 24/1200Z 29.8N 41.1W 35 KT 40 MPH 24H 25/0000Z 29.9N 42.2W 35 KT 40 MPH 36H 25/1200Z 29.9N 43.2W 35 KT 40 MPH 48H 26/0000Z 29.7N 44.1W 30 KT 35 MPH 60H 26/1200Z 29.6N 44.9W 30 KT 35 MPH...POST-TROP/REMNT LOW 72H 27/0000Z 29.8N 45.4W 25 KT 30 MPH...POST-TROP/REMNT LOW 96H 28/0000Z...DISSIPATED $$ Forecaster Hagen