Hurricane Chris Discussion Number 15
Wiki-Hurricanes Forecast Center
5:00 PM EDT Wed Jul 11 2018
Chris is showing mixed signs of strength this afternoon. On one hand, the eye has become more distinct and symmetrical compared to this morning. On the other hand, convection has weakened in the south and east quadrants of the hurricane, likely due to some dry air intrusion and cooler ocean temperatures. Satellite intensity estimates from SAB and TAFB are a unanimous T4.5/77kt, but T5.2/94.8kt from UW-CIMSS ADT and 89kt from SATCON. A blend of these values supports lowering the initial intensity slightly to 85kt.
The intensity forecast for the next few hours is complicated. After losing some organization this morning, the interaction between Chris and the upper-level trough has allowed it to stabilize. Dry air remains a transient feature at best, while ocean temperatures are actually expected to decrease to 28-29C around sunset before Chris crosses the sharp Gulf Stream gradient. Theoretically, there is a small window that exists for Chris to intensify before that point. This won't be represented in our forecast, but it would not be surprising. Entering tomorrow, Chris is expected to quickly make the transition to an extratropical cyclone as it more wholly interacts with the upper-level trough and passes over waters below 20C. On a consistent northeast trajectory, Chris should pass just southeast of Newfoundland between 24 and 36 hours, delivering tropical storm-force winds and heavy rainfall. A bend more toward the east is expected by day 2 before dissipation on day 3.
FORECAST POSITIONS AND MAX WINDS
INIT 11/2100Z 85 KT 100 MPH
12H 12/0600Z 80 KT 90 MPH
24H 12/1800Z 70 KT 80 MPH...POST-TROP/EXTRATROP
36H 13/0600Z 55 KT 65 MPH...POST-TROP/EXTRATROP
48H 13/1800Z 40 KT 45 MPH...POST-TROP/EXTRATROP