Hurricane Hector Discussion Number 43
Wiki-Hurricanes Forecast Center
5:00 AM HST Sun Aug 12 2018
Hector is being quickly stripped of its convective activity this early morning by strong southerly to southeasterly wind shear. While convection is still over the low-level circulation, the system as a whole as begun to take an atypical linear appearance as the shower activity fits the mold of the powerful upper-air flow. Microwave imagery suggests that the deep convection may not be rooted at the surface near the center of circulation, and perhaps we'll be seeing that materialize later today with an exposed vortex. Satellite intensity estimates are falling precipitously as the convection becomes much less organized. PHFO estimated T4.5/77kt while SAB estimated T4.0/65kt... these were both lagged current intensity estimates, with raw values significantly lower. UW-CIMSS ADT showed a lagged estimate of T4.3/72kt. The typically resistant SATCON has dropped even further to a 67kt estimated value. Given the rapid tumble of the storm's organization, I have opted to take the lowest value of these from SAB at 65 kt.
Hector is still tracking towards the northwest, but should begin moving towards the west-northwest soon as the ridge to the hurricane's north is expected to strengthen. A northward turn should begin in about four days due to the approach of a trough. Models are in good agreement over this track. What isn't in good agreement is the intensity forecast. While continued weakening is anticipated today with continued strong wind shear, some guidance suggests that a window of strengthening exists beginning in 24 hours. The HWRF is overtly extreme with a Category 3 equivalent, but this seems to be due to erroneous sea surface temperatures. The GFS, HMON, SHIPS, and LGEM show more realistic amounts of reintensification in marginal low-shear conditions. For now, the forecast shows Hector stabilizing tomorrow before some minor reintensification once the storm enters the Western Pacific. Lowering sea surface temperatures late in the forecast should bring about the storm's eventual demise.
MAXIMUM WINDS FORECAST
INIT 12/1500Z 65 KT 75 MPH
12H 13/0000Z 55 KT 65 MPH
24H 13/1200Z 55 KT 65 MPH
36H 14/0000Z 60 KT 70 MPH...WEST PACIFIC
48H 14/1200Z 60 KT 70 MPH...WEST PACIFIC
72H 15/1200Z 55 KT 65 MPH...WEST PACIFIC
96H 16/1200Z 50 KT 60 MPH...WEST PACIFIC
120H 17/1200Z 45 KT 50 MPH...WEST PACIFIC