000
WTPZ41 KNHC 142055
TCDEP1

Tropical Storm Karina Discussion Number   8
NWS National Hurricane Center Miami FL       EP162020
Issued by NWS Central Pacific Hurricane Center Honolulu HI
200 PM PDT Mon Sep 14 2020
 
The morning visible images showed Karina's partially obscured low 
level center under the northeast edge of the cyclone's deep 
convection. The displacement of the center is due to the ongoing 
presence of moderate vertical wind shear from the northeast. Cloud 
top temperatures have generally warmed through most of the morning, 
though the latest images showed a small burst of deep convection 
south of the center.  An ASCAT pass this morning showed a large 
swath of 35 kt winds in the southeastern semicircle of Karina's 
circulation. The initial wind radii have been increased to account 
for the updated data. Dvorak fixes came in at 35 kt from SAB, and 45 
kt from TAFB and PHFO. ASCAT peak winds were 37 kt. Based on a 
blend of these data, and little change in Karina's appearance in 
satellite imagery, the initial intensity will be held at 40 kt for 
this 
advisory.

Moderate shear is expected to continue to affect Karina for another 
24 hours. The shear will become weak from 36 to 72 hours, but by 
then the cyclone is expected to be over sub-26 degree C sea 
surface temperatures. Most of the objective aids indicate that peak 
intensity has been reached, and gradual weakening will occur after 
24 hours. The intensity forecast closely follows HCCA, and has 
Karina becoming a post-tropical remnant low by 96 hours, if not 
sooner. This forecast trend keeps the intensity higher than the 
statistical guidance.

The initial motion for this package is 305/9 kt. Karina is expected 
to continue moving northwestward to the southwest of a mid-level 
anticyclone. This motion is expected to continue through 60 to 72 
hours. Karina should turn toward the southwest as deep convection 
ceases and the cyclone becomes steered by the low level flow. The 
forecast track has been adjusted a bit northward from the previous 
forecast, in part due to an adjustment in the initial position, and 
closely follows the HCCA guidance.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  14/2100Z 18.5N 118.8W   40 KT  45 MPH
 12H  15/0600Z 19.4N 119.7W   40 KT  45 MPH
 24H  15/1800Z 20.8N 121.2W   40 KT  45 MPH
 36H  16/0600Z 21.9N 122.7W   35 KT  40 MPH
 48H  16/1800Z 23.0N 124.2W   30 KT  35 MPH
 60H  17/0600Z 23.7N 125.2W   25 KT  30 MPH
 72H  17/1800Z 24.0N 125.9W   25 KT  30 MPH
 96H  18/1800Z 23.5N 127.5W   25 KT  30 MPH...POST-TROP/REMNT LOW
120H  19/1800Z...DISSIPATED
 
$$
Forecaster Kodama