Post-Tropical Cyclone Chris Discussion Number 18
Wiki-Hurricanes Forecast Center
11:00 AM EDT Thu Jul 12 2018
Within the last six hours, the central convection that was once present over the center of Four has become completely sheared to the northeast, and a cold front now evidently extends from the system southwestward towards Bermuda as the system has acquired an extratropical structure. Winds have been hard to diagnose this morning due to a lack of scatterometer data and poorly positioned buoy observations. Given the weakening of convection while accounting for strong winds associated with baroclinic processes, the intensity for Four this advisory has been lowered to 60 kt.
Scattered showers are beginning to impact Newfoundland, with an expansive rainshield already over Nova Scotia and now beginning to move into Newfoundland. Hurricane-force wind gusts and tropical storm-force winds are expected to impact portions of the Canadian Maritimes, if not already. The center of Four is expected to reach the Avalon Peninsula this evening as the system tracks northeast, eventually curving east in response to a polar extratropical low. Models suggest that in merging, the remnants of Four should become the dominant center as it approaches Iceland this weekend.
FORECAST POSITIONS AND MAX WINDS
INIT 12/1500Z 60KT 70MPH...POST-TROP/EXTRATROP
12H 13/0000Z 55KT 65MPH...POST-TROP/EXTRATROP
24H 13/1200Z 45KT 50MPH...POST-TROP/EXTRATROP
36H 14/0000Z 40KT 45MPH...POST-TROP/EXTRATROP
48H 14/1200Z 35KT 40MPH...POST-TROP/EXTRATROP
72H 15/1200Z 30KT 35MPH...POST-TROP/EXTRATROP
96H 16/1200Z ... DISSIPATED