Hurricane Hector Discussion Number 40
Wiki-Hurricanes Forecast Center
5:00 PM HST Fri Aug 10 2018
Hector is on the verge of its expected weakening trend. Cloudtops became much warmer a few hours ago, and although they've cooled again recently, the overall appearance is slightly less organized than earlier with a sharp gradient in the southwestern quadrant indicative of increasing wind shear. Satellite intensity estimates were T5.5/102kt from PHFO, T6.0/115kt from SAB/PGTW, and T6.3/122kt from UW-CIMSS ADT (although raw values are now decreasing). Therefore, the initial intensity has been lowered to 115kt.
For the first time in a long time, Hector is in for a hurtin' soon. 0z SHIPS analyzed wind shear at 13kt and this value should only increase over the next 24 hours, perhaps to nearly 30kt. The hurricane has been shielded from dry air in a low shear environment, but now that upper-level winds are increasing, dry air (characterized by mid-level relative humidity values under 45 percent) should have no trouble being injected into the circulation. Ocean temperatures are warm--and actually increasing--for now but will fall to under 26C in about two days. Thus, steady to rapid weakening is expected over the coming days. The updated forecast is close to the previous one, with higher confidence now that the HMON/HWRF are not degenerating the storm so quickly.
The initial motion continues to be swiftly toward the west-northwest. A mid-level ridge to the north of Hector should weaken over the coming hours and direct the storm more northwest, a trajectory that should continue for the next 96 hours. By day 5, Hector should slow and turn more toward the west-northwest as indicated by most models.
MAXIMUM WINDS FORECAST
INIT 11/0300Z 115 KT 130 MPH
12H 11/1200Z 105 KT 120 MPH
24H 12/0000Z 95 KT 110 MPH
36H 12/1200Z 85 KT 100 MPH
48H 13/0000Z 75 KT 85 MPH
72H 14/0000Z 65 KT 75 MPH...WEST PACIFIC
96H 15/0000Z 55 KT 65 MPH...WEST PACIFIC
120H 16/0000Z 45 KT 50 MPH...WEST PACIFIC