By PDC’s Senior Weather
Specialist Glenn James
Tropical Cyclone 08S (Batsirai)…is located approximately 1032 NM east of St. Denis
According to the JTWC warning number 4…wind speeds are 45 knots with gusts to 55 knots.
Satellite imagery depicts ragged deep convection over a compact low level circulation center, reflecting the rapid weakening that has occurred over the past twelve hours following a very short-lived period of explosive deepening. Deep convection is displaced to the southern semi-circle…due to northerly vertical wind shear.
Batsorai is under moderate 15 to 20 knot shear. Sea surface temperature analysis indicates TC 08S is tracking over a tongue of slightly cooler waters.
TC 08S is expected to track generally south-southwesterly to westerly over the next 48 hours within the broader monsoonal gyre flow, which is modulated by the strong deep layer subtropical ridge to the south. Mid-level drying and persistent shear is forecast to hamper redevelopment during this period.
However, after 48 hours the track is expected to deflect equatorward, accompanied by increased moistening and a relaxation of the shear. A weakness in the ridge should then allow another turn to the south-southwest at the end of the forecast.
The small size of the current core, combined with the broader interaction with the gyre flow and the poor guidance reliability thus far make the intensity forecast challenging. The forecast is slightly higher than the current guidance envelop given the potential to rapidly adjust to any positive environmental changes, although the forecast calls for the shear and dry environment to limit intensification through 48 hours.
Although the forecast calls for the shear and dry environment to limit intensification through 48 hours. A secondary peak of 70 knots is anticipated around 96 hours as conditions improve.