Issued at 900 PM GMT Tue Sep 06 2022
370 WTNT45 KNHC 062040 TCDAT5 Hurricane Danielle Discussion Number 23 NWS National Hurricane Center Miami FL AL052022 900 PM GMT Tue Sep 06 2022 Danielle is holding its own over the north-central Atlantic. The cyclone's structure has stabilized since early this morning and the cloud tops have been cooling slightly over the past several hours, suggesting that any weakening that had been occurring overnight has temporarily ended. The initial intensity is being held at 65 kt for this advisory, which is based on the latest subjective Dvorak intensity estimate from SAB, and objective data from UW-CIMSS. The hurricane continues to move slowly east-northeastward, or 070/6 kt. There is no change to the forecast track reasoning. Danielle is expected to accelerate east-northeastward tonight in the increasing flow ahead of a digging upper-level trough. This trough is forecast to spawn a baroclinic system west of Danielle by late this week, forcing it to make a cyclonic loop while the two systems merge into a larger extratropical low. The merged system is then forecast to move east-southeastward to southeastward over the weekend. There were no significant changes to the NHC track forecast compared to the previous advisory, as model guidance remains in good agreement. Danielle is forecast to continue over SSTs of about 25 degrees C over the next 18-24 h, so only minor fluctuations in strength is indicated during that time. However, by late Wednesday the cyclone should cross a tight SST gradient and begin traversing over waters of 20 degrees C or less for the remainder of the forecast period. The combination of these cooler waters and the interaction with the baroclinic system should cause extratropical transition to complete by Thursday. The latest NHC intensity forecast closely follows the latest multi-model consensus. Danielle is producing a large area of very rough seas over the central-north Atlantic. More information can be found in the High Seas Forecasts issued by the Ocean Prediction Center under AWIPS header NFDHSFAT1, WMO header FZNT01 KWBC, and online at ocean.weather.gov/shtml/NFDHSFAT1.php. FORECAST POSITIONS AND MAX WINDS INIT 06/2100Z 42.5N 40.3W 65 KT 75 MPH 12H 07/0600Z 43.1N 38.6W 65 KT 75 MPH 24H 07/1800Z 44.6N 35.9W 65 KT 75 MPH 36H 08/0600Z 46.5N 33.2W 60 KT 70 MPH 48H 08/1800Z 48.8N 31.9W 55 KT 65 MPH...POST-TROP/EXTRATROP 60H 09/0600Z 50.3N 32.6W 50 KT 60 MPH...POST-TROP/EXTRATROP 72H 09/1800Z 50.0N 33.6W 45 KT 50 MPH...POST-TROP/EXTRATROP 96H 10/1800Z 47.1N 29.4W 40 KT 45 MPH...POST-TROP/EXTRATROP 120H 11/1800Z 44.1N 22.0W 35 KT 40 MPH...POST-TROP/EXTRATROP $$ Forecaster Latto
