霧峰追風者

JTWC 14Z評級LOW

    (2) AN AREA OF CONVECTION (INVEST 91S) HAS PERSISTED NEAR 8.9S
54.4E, APPROXIMATELY 740 NM NORTH OF LA REUNION. ANIMATED
MULTISPECTRAL SATELLITE IMAGERY AND A PARTIAL 211254Z SSMIS 91GHZ
MICROWAVE IMAGE SHOW FRAGMENTED CONVECTIVE BANDS WRAPPING INTO AN
ELONGATED LOW-LEVEL CIRCULATION. THE UPPER-LEVEL ENVIRONMENT
IS FAVORABLE WITH LOW VERTICAL WIND SHEAR (5-10 KNOTS) AND STRONG
POLEWARD OUTFLOW. SEA SURFACE TEMPERATURES ARE FAVORABLE AT 28-29C.
GLOBAL MODELS INDICATE A WESTWARD TRACK AND SHOW THE SYSTEM REACHING
TROPICAL STORM STATUS IN 48-72 HOURS. MAXIMUM SUSTAINED SURFACE
WINDS ARE ESTIMATED AT 20 TO 25 KNOTS. MINIMUM SEA LEVEL PRESSURE IS
ESTIMATED TO BE NEAR 1003 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS LOW.

霧峰追風者

The basin is in a near-equatorial trough (NET) pattern axed near 5S, with westerly winds at the
equator. Near 65E, the NET is broken into two branches, probably because of the passage of a dry
phase of a mixed Rossby-Gravity wave. A moderate convective activity is concentrated within these
two branches of NET : to the North-East of Madagasar and East of Diego Garcia. The development
of two suspect areas within both NET branches is suggested by the available guidance.

North of Madagascar :
From tomorrow, the upper divergence becomes excellent over the western NET branch. Monday, a
weak clockwise circulation could appear and gradually develop from Tuesday. Both the Euro and
American deterministic models are suggesting the formation of a significant tropical low from
Wednesday, North of the Mozambique Channel. This cyclogenesis risk is also shown within the
ensemble members of the last probabilistic runs. However, the lack of equatorward low-level
convergence could slow down the development of the system and keep it at a moderate intensity at
first.
For the next five days, the risk of formation of a moderate tropical storm becomes low
Thursday north of the Comoros archipelago.

East of Diego Garcia :
Benefiting from conducive environmental conditions aloft and from a good low-level convergence,
a clockwise circulation should emerge within the Eastern NET branch by the end of the week-end.
From Tuesday, the strengthening upper divergence should allow the development of the system. The
available guidance is in good agreement to forecast a moderate cyclogenesis risk for the second half
of next week.
For the next five days, the risk of formation of a moderate tropical storm becomes low
Wednesday then moderate from Thursday east of Diego Garcia.
The strengthening of the cyclonic activity expected next week over the basin is probably linked to
the combined passages of a Kelvin and an Equatorial Rossby waves.