Tropical Storm Lane Discussion Number 3
Wiki-Hurricanes Forecast Center
2:00 PM PDT Wed Aug 15 2018
Lane is becoming better organized this afternoon, with a symmetrical central dense overcast that has developed over the low-level circulation. Upper-level outflow is fantastic to the west but still restricted to the east as a result of the continued effects of ~10kt northeasterly wind shear. Satellite intensity estimates at 18z were T2.5/35kt from TAFB and T3.0/45kt from SAB, along with a more recent value of T3.3/51kt from UW-CIMSS ADT. A 1720z ASCAT pass indicated that the center was well embedded within convection, but that the circulation was elongated southwest to northeast. That same pass showed maximum winds no higher than 35kt in the southern quadrant. Given the improved presentation since that time, the initial intensity has been nudged upward to 40kt, even though this value is likely to be conservative in short order.
As mentioned above, northeasterly shear around 10kt continues to affect Lane, and this should continue for the next 36 hours or so. After that, upper-level winds are expected to fall below 5kt. In a moist environment and over water temperatures above 27C, steady to rapid intensification is expected. In fact, the new DTOPS rapid intensification index shows a 77 percent chance of 65kt development over the next 72 hours. The GFS is more bullish with Lane and now indicates a Category 3 hurricane while both the HMON/HWRF reach Category 4 intensity. The SHIPS and LGEM do not make Lane a major hurricane, but these models appear to be limited by fault sea surface temperature readings from the SHIPS that do not match actual conditions; thus, they have been discounted. The updated forecast is higher than the previous one but likely still conservative.
Lane is moving steadily west--or just south of due west. This motion will continue for the next 24 hours or so before a weakening subtropical ridge to Lane's north allows it to move more toward the west-northwest. The system is no threat to land in the immediate future, but may pose some threat to the Hawaiian Islands outside the forecast period.
MAXIMUM WINDS FORECAST
INIT 15/2100Z 40 KT 45 MPH
12H 16/0600Z 50 KT 60 MPH
24H 16/1800Z 65 KT 75 MPH
36H 17/0600Z 80 KT 90 MPH
48H 17/1800Z 95 KT 110 MPH
72H 18/1800Z 105 KT 120 MPH...ENTERING CENTRAL PACIFIC
96H 19/1800Z 115 KT 130 MPH
120H 20/1800Z 115 KT 130 MPH