000 WTPZ41 KNHC 080839 TCDEP1 Tropical Storm Kevin Discussion Number 4 NWS National Hurricane Center Miami FL EP112021 300 AM MDT Sun Aug 08 2021 Kevin has changed little overnight. Microwave data and infrared satellite imagery reveal that its convective bands are still somewhat fragmented with only modest curvature. Recent UW-CIMSS objective estimates and subjective Dvorak classifications from TAFB and SAB range from 35 to 45 kt, so the initial intensity is held at 40 kt for this advisory. Unfortunately, no recent scatterometer passes were available to better assess the cyclone's current intensity. The cyclone continues moving westward, or 270 degrees, at around 9 kt. This motion is expected for another 12 to 24 h, before a mid- to upper-level trough weakens the steering ridge and causes Kevin to move west-northwestward through midweek. Kevin is forecast to pass near or just south of Clarion Island on Tuesday. The track guidance is in good agreement for much of the forecast period, and the latest official NHC forecast lies near the previous one and generally follows the multi-model consensus aids. Kevin appears primed for some strengthening, as the cyclone will remain in a moist, unstable environment with ample oceanic heat content for the next couple of days. However, persistent northeasterly wind shear of 15-20 kt will likely curtail rapid intensification in an otherwise favorable environment. Despite the shear, the guidance supports strengthening in the near-term, and the official NHC forecast shows Kevin becoming a hurricane on Monday. The cyclone's intensity is forecast to level off by Tuesday, with weakening thereafter as Kevin moves over cooler waters and continues to battle moderate shear. The latest NHC intensity forecast is a little lower than the previous one, but remains near or slightly above the HFIP corrected consensus approach (HCCA) and IVCN aids. FORECAST POSITIONS AND MAX WINDS INIT 08/0900Z 15.8N 108.7W 40 KT 45 MPH 12H 08/1800Z 15.8N 109.6W 50 KT 60 MPH 24H 09/0600Z 16.1N 110.8W 60 KT 70 MPH 36H 09/1800Z 16.7N 112.0W 65 KT 75 MPH 48H 10/0600Z 17.5N 113.3W 70 KT 80 MPH 60H 10/1800Z 18.2N 114.8W 70 KT 80 MPH 72H 11/0600Z 19.1N 116.5W 65 KT 75 MPH 96H 12/0600Z 20.8N 120.0W 55 KT 65 MPH 120H 13/0600Z 22.5N 124.0W 40 KT 45 MPH $$ Forecaster Reinhart/Pasch