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#1105389 (Received by flhurricane at: 4:54 AM 02.Sep.2022) TCDAT5 Tropical Storm Danielle Discussion Number 5 NWS National Hurricane Center Miami FL AL052022 900 AM GMT Fri Sep 02 2022 Satellite imagery shows that Danielle is continuing to strengthen, with convective bands wrapping around the center and attempts at eye formation. The various satellite intensity estimates have a wide range from 45-77 kt, and the consensus of the estimates is that Danielle is not quite a hurricane yet. Based on these estimates, the initial intensity is increased to a possibly conservative 60 kt. Danielle continues to move slowly eastward, with the initial motion 100/3 kt. The cyclone is situated within an area of light steering flow on the south side of an omega block mid-level anticyclone, and this pattern is expected to cause Danielle to meander during the next couple of days. After that, the blocking anticyclone should move eastward and weaken, allowing the southern edge of the mid-latitude westerlies to become the primary steering mechanism. The large-scale models differ in the details of the shortwave troughs in the westerlies that could affect Danielle, and due to this the track guidance becomes somewhat divergent, with the ECMWF calling for a more northward motion than the other guidance. The new forecast track is similar to the previous forecast through 72 h, then is shifted a little to the north of the previous forecast. The cyclone should remain over 26-27C sea surface temperatures for about 72 h in an environment of light- to moderate westerly shear. This should allow continued strengthening, with the main negative factor being that the mid-level relative humidities near the storm are low. After 72 h, movement over cooler water and increased shear should cause weakening. However, the large-scale models are in good agreement that the cyclone will not undergo extratropical transition before the end of the forecast period. The new intensity forecast is an update of the previous forecast and lies near the intensity consensus. FORECAST POSITIONS AND MAX WINDS INIT 02/0900Z 37.9N 43.4W 60 KT 70 MPH 12H 02/1800Z 37.8N 43.4W 65 KT 75 MPH 24H 03/0600Z 37.8N 43.7W 70 KT 80 MPH 36H 03/1800Z 37.9N 44.2W 75 KT 85 MPH 48H 04/0600Z 38.2N 44.6W 80 KT 90 MPH 60H 04/1800Z 38.6N 44.4W 85 KT 100 MPH 72H 05/0600Z 39.2N 43.7W 85 KT 100 MPH 96H 06/0600Z 41.0N 41.4W 80 KT 90 MPH 120H 07/0600Z 42.5N 38.0W 75 KT 85 MPH $$ Forecaster Beven |