Hurricane Hector Discussion Number 31
Wiki-Hurricanes Forecast Center
11:00 AM HST Wed Aug 8 2018
Hector became dramatically less organized on satellite earlier today, with a less symmetric central dense overcast and obscured eye. However, since that time, deep convection has wrapped around an eye that is trying to fully clear again. A reconnaissance aircraft investigating the storm found peak flight-level winds of 112kt and maximum surface winds of 116-117kt. I'm unsure of how reliable the latter values are, but the plane found believable surface winds of 106kt. Therefore, the initial intensity has been slightly reduced to 105kt. The pressure is 959mb according to the last two center passes.
Soundings from the GFS indicate that Hector is being impacted by about 10kt of southwesterly shear from an active monsoon trough to its south. This shear appears to be responsible for Hector's decrease in organization earlier. SHIPS suggest this shear should persist for another 18-24 hours before decreasing. Meanwhile, Hector remains over waters near 26C, although these are expected to begin warming shortly. Recon data and microwave imagery reveals that the hurricane is undergoing an eyewall replacement cycle, with the inner eyewall remaining dominant for now. All of the factors above support some more weakening over the next 24 hours. From 36 to 72 hours, re-intensification is expected as Hector moves over waters warmer than 27C. On days 4 and 5, as Hector moves northwest into the subtropical Pacific, ocean temperatures should again decrease while upper-level winds increase courtesy of an expansive TUTT. Substantial weakening should occur during that time.
The hurricane is moving steadily westward on the south side of a mid-level ridge north of the Hawaiian Islands. As Hector reaches the western periphery of the high pressure area in about 48 hours, it should begin a curve toward the northwest. This trajectory should continue for the remainder of the period.
MAXIMUM WINDS FORECAST
INIT 08/1500Z 105 KT 120 MPH
12H 09/0000Z 100 KT 115 MPH...CLOSEST APPROACH TO HAWAII
24H 09/1200Z 95 KT 110 MPH
36H 10/0000Z 100 KT 115 MPH
48H 10/1200Z 105 KT 120 MPH
72H 11/1200Z 110 KT 125 MPH
96H 12/1200Z 100 KT 115 MPH
120H 13/1200Z 85 KT 100 MPH...WEST PACIFIC