Tropical Storm Kristy Discussion Number 11
Wiki-Hurricanes Forecast Center
8:00 AM PDT Thu Aug 9 2018
Kristy is showing some renewed signs of life this morning as convection has slowly become more organized, transitioning into something more akin to a curved band as opposed to a sheared convective blob with little internal organization. An AMSR-2 microwave pass at 1046Z this morning showed a fairly characteristic curved band wrapping about a circular area of mid-level subsidence, perhaps an attempt to jumpstart an eye at an uncharacteristically low intensity. The organization this morning have allowed SAB and TAFB to raise their estimates to a consensus T3.5/55kt, with UW-CIMSS ADT in full agreement. However, even with this consensus, uncertainty over the precise Dvorak scene type due to the presence of shear casts some doubt on the 55 kt intensity. SATCON with new microwave data gave a 51 kt consensus value, so for now the intensity for Kristy has been set to a possibly conservative 50 kt.
An ease in poleward outflow blocking as allowed cirrus to spread forth northward, indicative of good ventilation on the northern semicircle, though the motions of cirrus in the southwestern quadrant indicate some southwesterly shear is impacting the system. Marginal conditions today could allow for some marginal strengthening today and tomorrow, but given the approach of some oncoming shear, I have kept intensity in this window steady. a decline in sea surface temperatures throughout the forecast window, especially after 36 hours, should bring Kristy down to a remnant low in around four days, with models in decent agreement towards these drying conditions. Kristy has begun to move north as it feels the circulation of John and a nearby mid-level low to Kristy's northeast. Kristy could turn a bit to the north-northeast as it draws closer to these features. The system's ultimate fate is dependent on its proximity to John, with either absorption or a drift west possible once Kristy degenerates, but regardless it is expected to be rather diffuse in five days.
MAXIMUM WINDS FORECAST
INIT 09/1500Z 50 KT 60 MPH
12H 10/0000Z 50 KT 60 MPH
24H 10/1200Z 45 KT 50 MPH
36H 11/0000Z 45 KT 50 MPH
48H 11/1200Z 40 KT 45 MPH
72H 12/1200Z 35 KT 40 MPH
96H 13/1200Z 30 KT 35 MPH...POST-TROP/REMNT LOW
120H 14/1200Z 25 KT 30 MPH...POST-TROP/REMNT LOW