Tropical Storm Debby Discussion Number 9
Wiki-Hurricanes Forecast Center
11:00 AM AST Thu Aug 9 2018
Debby has managed to be quite resiient this morning with its convective activity, and despite being sheared, has managed to tow a new area of -55°C to -65°C convection close to its south, though the low-level center of circulation remains largely exposed. SAB continued to estimate a T2.5/35kt current intensity, though an ASCAT scatterometer pass from 1231Z showed a rather larger than expected area of gale-force winds, so once again the intensity for Debby has been set once again at 40 kt. I hope my forecasting colleague is not annoyed by these developments.
This morning's convection draws out the clock for a transition into a remnant low for longer, but Debby's fate as a tropical cyclone is still sealed at this point as it tracks northeast around a larger extratropical cyclone. Interestingly, Debby has proved resilient enough for model guidance to keep Debby around as an extratropical cyclone, and in fact, some models allow Debby to grow baroclinically and absorb the extratropical cyclone currently steering Debby. I'm not sure how valid this specific scenario is, but with respect for good consensus on system maintenance I've extended dissipation out to 36 hours instead of 12-24 hours.
MAXIMUM WINDS FORECAST
INIT 09/1500Z 40 KT 45 MPH
12H 10/0000Z 35 KT 40 MPH
24H 10/1200Z 35 KT 40 MPH...POST-TROP/REMNT LOW