Tropical Storm Kristy Discussion Number 6
Wiki-Hurricanes Forecast Center
2:00 AM PDT Wed Aug 8 2018
Kristy is in no hurry to do anything of note this morning. Deep convection has expanded over the low-level center, but this mass is amorphous. The storm continues to experience moderate shear from a nearby upper-level low, and this shear is helping to inject environmental dry air into Kristy. Satellite intensity estimates ranged from T2.2/32kt from UW-CIMSS ADT to T2.5/35kt from TAFB to T3.0/45kt from SAB. A blend of these values supports leaving the initial intensity at 35kt, directly in line with a 0533z ASCAT pass which indicated one tropical storm-force barb in the northeastern quadrant.
The intensity forecast is becoming clearer, and it isn't good news for Kristy. Shear from the nearby upper-level low is expected to slacken in about 18 hours. However, with Kristy over sub-27C ocean temperatures, and with no real organization, it is appearing more likely that only slight intensification, if any, is likely through the forecast period. This is confirmed by the SHIPS/LGEM/GFS which show only weakening from here on out. The HWRF continues to make Kristy a hurricane, but it's on its own boat here and has been discounted. The ECMWF shows the potential for slight development over the next 48 hours. The updated forecast has been further lowered from the previous one. Degeneration has been left unchanged at day 5, but if the dynamical models and the GFS are correct, this could occur much sooner.
Kristy is moving west-northwest but should turn north over the next day in response to an upper-level low to its northwest and Hurricane John to its northeast. The pull of John's large circulation should keep Kristy on this heading through day 4. A crossroads opens up thereafter, with the potential for John to send the remnants northeast if the two disturbances are in close enough proximity, and with the potential for Kristy to turn west within low-level flow if interaction is less.
MAXIMUM WINDS FORECAST
INIT 08/0900Z 35 KT 40 MPH
12H 08/1800Z 35 KT 40 MPH
24H 09/0600Z 40 KT 45 MPH
36H 09/1800Z 40 KT 45 MPH
48H 10/0600Z 45 KT 50 MPH
72H 11/0600Z 45 KT 50 MPH
96H 12/0600Z 40 KT 45 MPH
120H 13/0600Z 30 KT 35 MPH...POST-TROP/REMNT LOW