Hurricane Hector Discussion Number 10
Wiki-Hurricanes Forecast Center
8:00 PM PDT Thu Aug 2 2018
Hector has certainly fluctuated in intensity today. After rapidly intensifying into a hurricane during the pre-dawn hours, and continuing on to become a major hurricane shortly after the previous advisory, geostationary and microwave imagery over the past few hours shows that the storm has temporarily weakened. The eye, which was once distinct, has been obscured on infrared images. From the perspective of microwave imagery, the northern eyewall has eroded, a sign that the increase in upper-level winds that was seemingly advertised for naught earlier today have finally taken shape. Satellite intensity estimates have decreased to T4.5/77kt from both SAB and TAFB, while UW-CIMSS ADT values are rapidly decreasing. Given persistence and the fact the central dense overcast still remains symmetric, the initial intensity is set to 90kt.
Now that wind shear is having a noticeable impact on Hector, the only question is how long it will continue to. Based on model guidance, the answer points to not very long. SHIPS, which analyzed shear at 15kt at 0z, decreases upper-level winds below 10kt within 6 hours, and even further below 5kt by this time tomorrow. This is in agreement with soundings from the GFS. With ocean temperatures hovering on either side of 27.0C for the next five days, and with Hector embedded within a pouch of deep moisture, intensification seems likely to begin overnight and continue for the next three days. By days four and five, mid-level relative humidity values below 45 percent should promote a gradual weakening trend, although Hector is likely to remain a potent hurricane throughout the period.
The hurricane continues to move swiftly west, dictated by an expansive mid-level ridge to its north. A turn toward the west-southwest is expected to begin shortly as this feature intensifies. By day 3, a weakening of the ridge should cause Hector to turn toward the west-northwest. It is still too early to determine how close Hector will come to the Hawaiian Islands and what impacts will occur as a result.
FORECAST POSITIONS AND MAX WINDS
INIT 03/0300Z 90 KT 105 MPH
12H 03/1200Z 95 KT 110 MPH
24H 04/0000Z 105 KT 120 MPH
36H 04/1200Z 110 KT 125 MPH
48H 05/0000Z 115 KT 130 MPH
72H 06/0000Z 110 KT 125 MPH
96H 07/0000Z 105 KT 120 MPH
120H 08/0000Z 95 KT 110 MPH