Hurricane Hector Discussion Number 25

Wiki-Hurricanes Forecast Center

5:00 PM HST Mon Aug 6 2018

An Air Force reconnaissance aircraft investigating Hector earlier found maximum flight-level winds of 147kt and peak surface winds of 137kt, a simple blend of which yielded 130kt. Since that time, the hurricane has changed little in appearance, with a warmer eye temperature but slightly less intense convection throughout the central dense overcast. Satellite intensity estimates were a consensus T6.5/125kt from SAB, TAFB, and PHFO. However, given the fairly steady state of the hurricane, the initial intensity will remain 130kt. It is worth noting that a series of microwave passes from 22z to 0z indicated the development of a spiral band to the west of the eye, suggesting Hector may be losing some of its annular characteristics. A new Hurricane Hunter plane will investigate Hector around 05:30z.

Hector is moving north of due west this evening and should continue on such a path for the next 24 hours or so. Thereafer, high pressure north of Hector should intensify and force the storm toward the west. Models are in good agreement that such a solution should keep the hurricane south of the Hawaiian Islands, where a landfall is not expected but fringe effects are still anticipated. This ridge should weaken on days 4 and 5, forcing Hector toward the west-northwest over the open Central Pacific.

We have forecast weakening for numerous advisories, and it has still not occurred despite ocean temperatures below 27C. This can be attributed to its annular characteristics and the tenacity of such cyclones compared to average systems. That being said, with sea surface temperatures expected to cool slightly more, and with very dry mid-level air forecast to encapsulate the hurricane beginning tomorrow morning, I have no choice but to forecast some weakening over the next 72 hours. By days four and five, water temperatures should increase to near 27C while mid-level relative humidity values rise above 40 percent and wind shear remains very light. This should promote re-intensification. Hector is expected to remain a powerful hurricane for the next 5 days, and likely much longer.


INIT 07/0300Z 130 KT 150 MPH

12H 07/1200Z 125 KT 145 MPH

24H 08/0000Z 120 KT 140 MPH

36H 08/1200Z 115 KT 130 MPH

48H 09/0000Z 110 KT 125 MPH

72H 10/0000Z 105 KT 120 MPH

96H 11/0000Z 110 KT 125 MPH

120H 12/0000Z 115 KT 130 MPH