528 
 WTPA42 PHFO 200913
 TCDCP2
  
 Hurricane Lane Discussion Number  22
 NWS Central Pacific Hurricane Center Honolulu HI   EP142018
 1100 PM HST Sun Aug 19 2018
  
 Aircraft from the NOAA Aircraft Operation Center and the U.S. Air
 Force Reserves 53rd Weather Reconnaissance Squadron have been
 sampling Hurricane Lane this evening. The data provided by these
 missions have been invaluable. Based on satellite intensity
 estimates ranging from 87 to 102 knots and Lane's poor
 representation in satellite imagery, we might have considered
 weakening the hurricane. Instead, the aircraft found peak
 flight-level and SFMR winds of 113 knots in the northwest
 quadrant. In addition, a dropsonde estimated surface wind of 117
 knots was also found in the northwest eyewall. Based on these
 aircraft observations, we have increased the initial intensity to
 110 knots.
 
 The initial motion for this advisory is 275/12 knots. Lane continues
 tracking westward along the southern flank of a large subtropical
 ridge. There is still quite a bit of spread in track guidance beyond
 day 2 as individual models handle the erosion of the western portion
 of this ridge differently, due to the forecast of an upper-level
 trough digging down northwest of the main Hawaiian Islands later
 this week. The latest forecast track through 48 hours is close to
 the previous forecast. However, due to overwhelming evidence that
 the western end of the ridge will erode from days 3 through 5, we
 had to shift the track far to the right. The latest forecast track
 remains to the right of the ECMWF, which is far left of the GFS,
 HWRF, and consensus models.
  
 The latest intensity forecast has been nudged up slightly compared
 with the previous one. This is based on the stronger initial
 intensity based on the aircraft, as well as the latest guidance.
 Lane will remain over 27-28 degree C waters through the forecast
 period. Shear of 10 to 15 knots is expected during the next 12
 hours, followed by reduced shear during the 24 to 48 hour time
 periods. After that, increasing vertical shear is expected to cause
 steady weakening, with Lane possibly becoming a tropical storm by
 Day 5. This intensity forecast closely follows the IVCN consensus
 guidance.
  
 Due to the large uncertainty in the future track and intensity of
 Lane, all interests in the Hawaiian Islands should continue to
 monitor the future progress of this system. Based on the latest
 trends in the forecast, direct impacts on the islands can not be
 ruled out. The latest trends in tropical cyclone wind speed
 probabilities also suggest that a Tropical Storm Watch may be
 needed for some parts of the island chain early this week.
  
  
 FORECAST POSITIONS AND MAX WINDS
  
 INIT  20/0900Z 13.8N 147.0W  110 KT 125 MPH
  12H  20/1800Z 13.9N 148.6W  110 KT 125 MPH
  24H  21/0600Z 14.1N 150.5W  110 KT 125 MPH
  36H  21/1800Z 14.4N 152.3W  105 KT 120 MPH
  48H  22/0600Z 14.7N 153.8W   95 KT 110 MPH
  72H  23/0600Z 15.9N 156.6W   85 KT 100 MPH
  96H  24/0600Z 17.5N 158.5W   75 KT  85 MPH
 120H  25/0600Z 20.0N 160.5W   60 KT  70 MPH
  
 $$
 Forecaster Houston