Hurricane Hector Discussion Number 21
Wiki-Hurricanes Forecast Center
8:00 PM PDT Sun Aug 5 2018
Hector remains an impressive hurricane this evening, with a ring of deep convection wrapped around a distinct eye. Satellite intensity estimates were T6.0/115kt from SAB and TAFB, with a recent estimate of T6.5/127kt from UW-CIMSS ADT. It is worth pointing out that the extent and organization of deepest convection was most impressive around 22z, at which point the hurricane was likely near 125kt, and that the coldest cloudtops have warmed slightly over the past few hours. Nonetheless, a blend of satellite estimates yields a possibly generous initial intensity of 120kt at this time.
There are no changes in the track to report. The storm is moving west-northwest, and this motion should continue for the next 24 hours when the mid-level ridge to its north is at its weakest. Thereafter, a re-intensification of the high pressure should force Hector west, a track that should keep it south of Hawaii, albeit close enough to deliver impacts. The westward trajectory is expected to continue through the rest of the forecast period.
Hector has intensified as expected today, but it is likely at its peak intensity. While wind shear remains below 10kt and may even decrease further over the coming days, ocean temperatures are expected to fall below 27C for an extended period of time. This, coupled with decreasing mid-level relative humidity values, should cause some weakening. The degree of weakening is still expected to be less than normal tropical cyclones thanks to Hector's annular characteristics. After day 4, sea surface temperatures should climb back above 27C and the environment should become increasingly moist, allowing for strengthening once again. The updated forecast is not vastly different from the previous one.
FORECAST POSITIONS AND MAX WINDS
INIT 06/0300Z 120 KT 140 MPH
12H 06/1200Z 115 KT 130 MPH
24H 07/0000Z 110 KT 125 MPH
36H 07/1200Z 105 KT 120 MPH
48H 08/0000Z 95 KT 110 MPH
72H 09/0000Z 90 KT 105 MPH...CLOSEST APPROACH TO HAWAII
96H 10/0000Z 90 KT 105 MPH
120H 11/0000Z 95 KT 110 MPH