Tropical Cyclone Francisco Redevelops Near East Coast of Madagascar

After moving slowly westward across the Southwest Indian Ocean for the past few days, Tropical Cyclone Francisco redeveloped near the east coast of Madagascar on Thursday.  At 7:00 a.m. EST on Thursday the center of Tropical Cyclone Francisco was located at latitude 17.9°S and longitude 50.7°E which put it about 90 miles (145 km) east of Toamasina, Madagascar.  Francisco was moving toward the west at 6 m.p.h. (9 km/h).  The maximum sustained wind speed was 45 m.p.h. (75 km/h) and there were wind gusts to 60 m.p.h. (95 km/h).  The minimum surface pressure was 1004 mb.

Strong vertical wind shear weakened Tropical Cyclone Francisco east of Rodrigues last Thursday, but the lower portion of the circulation remained intact.  The lower level circulation drifted slowly westward during the last seven days and it moved across Mauritius and La Reunion earlier the week.  More thunderstorms began to develop around the lower level circulation on Wednesday, when it moved closer to the east coast of Madagascar.  Bands of showers and thunderstorms began to reform.  Storms near the center of circulation started generating upper level divergence which pumped mass away from the tropical cyclone.  The removal of mass allowed the surface pressure to decrease and the wind speeds began to increase.

Tropical Cyclone Francisco has exhibited greater organization in recent hours.  However, the distribution of thunderstorms was asymmetrical.  Many of the stronger thunderstorms were occurring in bands in the western half of the circulation.  Bands in the eastern half of the circulation consisted primarily of showers and lower clouds.  Francisco was moving under the northern part of an upper level ridge.  The ridge was producing easterly winds which were blowing toward the top of the circulation.  Those winds were causing some vertical wind shear and the shear could be responsible for the asymmetrical distribution of thunderstorms.

Tropical Cyclone Francisco will move through an environment favorable for intensification during the next 6 to 12 hours.  Francisco will move over water where the Sea Surface Temperature is near 28°C.  The upper level ridge will still cause vertical wind shear, but the shear will not be strong enough to prevent intensification.  Tropical Cyclone Francisco will weaken when it moves over Madagascar.

Tropical Cyclone Francisco will move north of a high pressure system over the Southwest Indian Ocean.  The high will steer Francisco toward the west.  On its anticipated track Tropical Cyclone Francisco could make landfall on the east coast of Madagascar in about 12 hours.  Francisco will drop locally heavy rain over parts of central Madagascar.  The heavy rain could cause flash floods in some locations,

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