je.st
news
Tropical Depression Twenty-Seven Forecast Discussion Number 1
2020-10-19 14:05:33| National Hurricane Center (Atlantic)
Issued at 800 AM AST Mon Oct 19 2020 000 WTNT42 KNHC 191205 TCDAT2 Tropical Depression Twenty-Seven Special Discussion Number 1 NWS National Hurricane Center Miami FL AL272020 800 AM AST Mon Oct 19 2020 Deep convection associated with the area of low pressure over the central Atlantic has become significantly better organized overnight. The low-level center is located near the western edge of the convection, but the system has enough organization to be declared a tropical cyclone. Therefore, advisories are being initiated at this time. The system appears to be near tropical-storm strength, but since earlier classifications were just below that intensity the system is being started as a 30-kt tropical depression. The system appears more tropical than subtropical since it is no longer co-located with an upper-level low and it appears to have a fairly small radius of maximum winds. Therefore, it has been designated a tropical cyclone. Scatterometer data later this morning should provide a better assessment of the system's intensity. The depression is located over SSTs over 27-28 degrees Celsius and within an area of moderate westerly shear. These conditions should allow for gradual strengthening over the next day or so. After that time, the shear is expected to decrease and continued strengthen is anticipated. The NHC intensity forecasts calls for the system to become a hurricane within 72 hours, and is in best agreement with the HCCA and ICON intensity consensus models. The depression is located in an area of weak steering currents near the base of a mid- to upper-level trough that extends southwestward from the northeastern Atlantic. As a result, little net motion is expected through tonight. A mid- to upper-level ridge is forecast to build over the western and central Atlantic to the north of the system by midweek. As the ridge slides eastward later this week, the cyclone should move west-northwestward to northwestward at a faster rate of speed. This motion will bring the system close to Bermuda by late week and the interests on that island should closely monitor the progress of the cyclone. The dynamical models are in relatively good agreement on the overall scenario and the NHC track forecast is near the center of the guidance envelope. FORECAST POSITIONS AND MAX WINDS INIT 19/1200Z 25.8N 55.5W 30 KT 35 MPH 12H 19/1800Z 25.8N 55.4W 35 KT 40 MPH 24H 20/0600Z 26.0N 55.3W 45 KT 50 MPH 36H 20/1800Z 26.9N 55.9W 50 KT 60 MPH 48H 21/0600Z 28.0N 57.8W 55 KT 65 MPH 60H 21/1800Z 28.6N 59.3W 60 KT 70 MPH 72H 22/0600Z 29.5N 60.3W 65 KT 75 MPH 96H 23/0600Z 31.7N 62.3W 70 KT 80 MPH 120H 24/0600Z 33.5N 63.8W 75 KT 85 MPH $$ Forecaster Brown
Tags: number
discussion
tropical
depression
Category:Transportation and Logistics