Official Discussion issued by the National Hurricane Center
Kirk (AL122024) DATA RELEASED: 10/1/2024 9:00:00 AM UTC
Copy of official data Tropical Storm Kirk Discussion Number 7 NWS National Hurricane Center Miami FL AL122024 500 AM AST Tue Oct 01 2024 Satellite imagery indicates that Kirk's structure hasn't changed very much over the past 6 h. The infrared imagery consists of a large comma-shaped area of deep convection. ASCAT data from Monday evening as well as a more recent 01/0416 AMSR2 image indicate that the center is near the northern edge of the convection. The AMSR2 image also indicates that the convective bands haven't become any better organized around the center over the past 6 h. The latest subjective Dvorak intensity estimates range from 45 to 55 kt, and the latest objective intensity estimates from UW-CIMSS range from 49 to 56 kt. Given that the highest ASCAT vectors from around 0000 UTC were about 43 kt, and taking into account the recent intensity estimates, the initial intensity is set to 50 kt, which is unchanged from the previous NHC advisory. Kirk is estimated to be moving west-northwestward, or 295/12 kt. This general motion should continue for the next day or so while Kirk moves around the southwestern periphery of a deep-layer subtropical ridge over the eastern Atlantic. A gradual turn toward the northwest is expected during the middle part of the week, followed by a recurvature to the north over the central Atlantic by the end of the forecast period. The track guidance is in good agreement for the first couple days of the forecast, with a bit of spread noted thereafter. The new NHC track forecast is similar to the previous official forecast through 72 h, and west of the previous forecast at days 4 and 5, close to the multi-model consensus aid TVCA. Favorable environmental conditions are forecast to persist along Kirk's path through the next 4 days or so, with warm ocean waters, weak vertical wind shear and a relatively moist and unstable atmosphere. Kirk has a broad structure with a large wind field. The tropical storm force radii are forecast to continue increasing through the forecast period. This structure could limit Kirk's chances for rapid strengthening, despite the favorable environment. Little change has been made to the NHC intensity forecast, which calls for steady strengthening over the next 3 days. The NHC intensity forecast is near the high end of the guidance envelope. Kirk is forecast to become a large, major hurricane over the open central Atlantic later this week. FORECAST POSITIONS AND MAX WINDS INIT 01/0900Z 14.9N 38.0W 50 KT 60 MPH 12H 01/1800Z 15.5N 39.6W 60 KT 70 MPH 24H 02/0600Z 16.5N 41.4W 75 KT 85 MPH 36H 02/1800Z 17.6N 43.1W 85 KT 100 MPH 48H 03/0600Z 18.7N 44.4W 95 KT 110 MPH 60H 03/1800Z 19.9N 45.8W 105 KT 120 MPH 72H 04/0600Z 21.1N 47.1W 110 KT 125 MPH 96H 05/0600Z 24.2N 49.7W 110 KT 125 MPH 120H 06/0600Z 29.0N 49.7W 100 KT 115 MPH $$ Forecaster Hagen |