500 PM HST Mon Aug 20 2018 Visible satellite imagery this afternoon shows an impressive, distinct eye on Hurricane Lane, though the convection surrounding the core looks more ragged on the last few infrared images. A 2258Z AMSR2 pass indicated that Lane had a concentric eyewall structure. Satellite intensity estimates ranged from 5.5 from SAB and JTWC to 6.0 from PHFO. CIMSS ADT had 5.5 at 0000Z but has since risen to 6.0. Based on these estimates and the earlier reconnaisance data, we have maintained a 115 kt intensity for this advisory. Another aircraft reconnaisance mission will investigate Lane this evening. The initial motion estimate continues to be 280/10. A subtropical ridge to the north of Lane continues to steer the system westward. However, changes in the steering pattern are expected relatively soon, as the ridge weakens ane leaves a weakness to the north of Lane. This will allow the tropical cyclone to begin gaining latitude a little more quickly by 48 hours. The models are struggling with a couple of factors that make the track forecast beyond 48 hours very challenging. One is the evolution of a new ridge which develops to the east and southeast of Lane, and the other is the effect of gradually increasing shear. The ECMWF is stronger with the ridge, and starts shearing the system sooner, so the track is on the left side of the guidance envelope. The GFS and NAVGEM are quite a bit weaker with the ridge, and keep Lane away from the westerly shear longer. There do not appear to be any clear signals at this point to suggest which track to favor, and so we continue to follow the consensus guidance which is down the middle of an uncomfortably large guidance envelope. A turn more toward the west is expected toward the end of the period as Lane is expected to be decoupled and move as a shallower system in the trades. The rather large uncertainty in the track forecast necessitates close attention by interests in the Hawaiian Islands over the next couple of days. It is important to not focus your attention on the exact forecast track, and be prepared for changes to the forecast. Weak to moderate southwesterly shear and sea surface temperatures near 28C are sufficient to allow Lane to maintain intensity for the next 24 hours or so. Some fluctuations in intensity are possible due to difficult to forecast eyewall replacement cycles. As mentioned before, increasing shear will lead to a gradual weakening trend at first, with more rapid weakening expected beyond 72 hours as Lane approaches stronger winds aloft from a subtropical jet stream. The larger than normal uncertainty in the future track of Lane necessitates close attention by interests in the Hawaiian Islands over the next few days as Lane approaches the islands. It is important not to focus on the exact forecast track, and be prepared for changes to the forecast.