je.st
news
Hurricane Florence Forecast Discussion Number 26
2018-09-05 22:33:39| National Hurricane Center (Atlantic)
Issued at 500 PM AST Wed Sep 05 2018 107 WTNT41 KNHC 052033 TCDAT1 Hurricane Florence Discussion Number 26 NWS National Hurricane Center Miami FL AL062018 500 PM AST Wed Sep 05 2018 Florence has continued to intensify during the day, with colder cloud tops completely encircling a clearer eye. Both subjective and objective Dvorak estimates have unanimously increased to T6.0/115 kt, and on this basis, the initial intensity is raised to 115 kt, making Florence a category 4 hurricane. Florence appears to be right along the southern edge of a zone of stronger vertical shear and continues to defy the intensity guidance, which has consistently been predicting weakening. That said, the last few satellite images indicate that the eye may be becoming slightly disrupted by the shear. Since the shear is anticipated to increase during the next day or so, gradual weakening is shown in the short-term official forecast, which lies along the upper end of the guidance through 48 hours. Beyond 48 hours, vertical shear is anticipated to weaken, which would allow Florence to intensify and potentially regain major hurricane status. However, Florence will need to thread the needle between areas of stronger shear for this to happen, and there is significant uncertainty in the intensity forecast. The new official intensity forecast is little changed from before except to adjust upward to account for the higher initial intensity. The initial motion estimate remains northwestward, or 305/11 kt. Strong upper-level ridging is forecast to strengthen north of Florence over the next few days, forcing the hurricane to turn toward the west-northwest through about 48 hours. Track guidance is good agreement during this period, and the official forecast is essentially an update to the previous one. Beyond day 2, a break forms in the ridge, which results in a weakening of the steering currents, a slowdown in Florence's forward speed, and a turn back toward the northwest. The new official forecast is shifted south a bit on days 3-5 to account for recent model trends and is closest to the TVCN consensus. It should be noted that there is considerable model ensemble spread and run-to-run variability for Florence's track beyond day 5. Given the large uncertainty at these time ranges, it is far too soon to speculate what, if any, impacts Florence may have on the U.S. East Coast next week. Regardless of Florence's eventual track, large swells emanating from the hurricane will reach Bermuda beginning on Friday, resulting in life-threatening surf and rip currents on the island. Swells from Florence could also reach the U.S. East Coast by early next week. FORECAST POSITIONS AND MAX WINDS INIT 05/2100Z 22.7N 46.6W 115 KT 130 MPH 12H 06/0600Z 23.5N 48.1W 110 KT 125 MPH 24H 06/1800Z 24.5N 49.7W 105 KT 120 MPH 36H 07/0600Z 25.2N 51.3W 100 KT 115 MPH 48H 07/1800Z 25.5N 52.9W 95 KT 110 MPH 72H 08/1800Z 26.0N 55.3W 100 KT 115 MPH 96H 09/1800Z 27.0N 57.4W 105 KT 120 MPH 120H 10/1800Z 29.0N 60.0W 105 KT 120 MPH $$ Forecaster Berg/Rhome
Tags: number
discussion
forecast
florence
Category:Transportation and Logistics
Latest from this category |
All news |
||||||||||||||||||
|
|||||||||||||||||||