Tropical Storm Debby Discussion Number 4
Wiki-Hurricanes Forecast Center
5:00 AM AST Wed Aug 8 2018
Debby has made the transition to a fully tropical cyclone. Satellite imagery shows that the convection that began building south of the center prior to the last advisory has only grown and deepened, now obscuring the low-level circulation. What appears to be a spiral band has also formed in the southern quadrant. The earlier 0z ASCAT pass depicted a tight wind field more associated with tropical cyclones than subtropical cyclones. Finally, a 0356z GMI microwave pass indicated a nearly closed low-level eye-like feature. Given the increase in organization, the initial intensity has been set to 40kt, closest to a satellite estimate of T2.7/39kt from UW-CIMSS ADT.
Debby is moving northward but should make the turn northeast very soon, ahead of an upper-level trough approaching from the west. Models are in good agreement that Debby should be absorbed by this feature in about 36 hours. Before that time, an environment of moderate wind shear, marginal ocean temperatures, adequate moisture, and conditional instability fueled by cooler-than-average upper-level temperatures could allow for slight intensification.
FORECAST POSITIONS AND MAX WINDS
INIT 08/0900Z 40 KT 45 MPH
12H 08/1800Z 45 KT 50 MPH
24H 09/0600Z 40 KT 45 MPH