821 WTPZ42 KNHC 081459 CCA TCDEP2 Hurricane Olivia Discussion Number 32...Corrected NWS National Hurricane Center Miami FL EP172018 800 AM PDT Sat Sep 08 2018 Corrected initial intensity in the text from 70 to 75 kt. Satellite images indicate that Olivia continues to slowly weaken. The eyewall convection has warmed during the past several hours, with some breaks noted in the northwestern quadrant. A blend of the various intensity estimates gives a value of 75 kt for this advisory. Olivia is forecast to stay a hurricane for the next couple of days while the system is experiencing light shear, balanced by very dry air aloft and marginal but warming SSTs. While the forecast is flat-lined through 48 hours, don't be surprised if the system's intensity fluctuates upward at times, as many eastern Pacific cyclones have done so this season within a marginal environment. After the weekend, most of the guidance indicates that westerly shear should increase, which will likely cause weakening while Olivia approaches the Hawaiian Islands. The new intensity forecast is basically an update of the previous one and is close to the consensus. Olivia has turned westward and is moving 275/13. A building subtropical ridge should steer the hurricane basically due westward for the next couple of days, and the model guidance is in good agreement during this time. Thereafter, a mid-level ridge over Hawaii will impart some northerly steering flow on Olivia, which should cause the cyclone to move west-southwestward toward the main Hawaiian Islands. There isn't great agreement on how fast it will turn, however, due to the forecast depth of Olivia. The guidance generally indicates a stronger system will turn more southwestward, like the GFS or UKMET solutions, while a weaker system would have less of a turn, like the ECMWF or HWRF solutions. The model consensus has barely budged since the previous advisory, so little change has been made. Since the track seems to be dependent on the intensity at long range, this isn't a particularly confident forecast. KEY MESSAGES 1. Olivia is forecast to approach the main Hawaiian Islands from the east early next week, but it is too soon to determine the exact location and magnitude of any impacts. Interests in Hawaii should monitor the progress of Olivia this weekend and use this time to enact your hurricane action plan. 2. Do not focus on the exact track or intensity forecast, or any specific landfall location, as errors can be large at extended time ranges. Tropical storm or hurricane conditions could be felt anywhere in the islands as significant impacts could extend well away from the center. FORECAST POSITIONS AND MAX WINDS INIT 08/1500Z 21.4N 138.0W 75 KT 85 MPH 12H 09/0000Z 21.6N 140.1W 65 KT 75 MPH 24H 09/1200Z 21.7N 142.8W 65 KT 75 MPH 36H 10/0000Z 21.7N 145.2W 65 KT 75 MPH 48H 10/1200Z 21.7N 147.2W 65 KT 75 MPH 72H 11/1200Z 21.2N 151.0W 60 KT 70 MPH 96H 12/1200Z 20.2N 155.6W 55 KT 65 MPH 120H 13/1200Z 19.0N 160.5W 45 KT 50 MPH $$ Forecaster Blake