Tropical Cyclone Nisha

[Somerset Squall]

A disturbance near the island of American Samoa has rapidly developed through the day, and a tropical cyclone has formed, named Nisha. Current intensity is 35kts. Nisha looks very impressive indeed on satellite imagery, with a solid central dense overcast feature and spiral banding flanking the storm. Conditions are excellent it has to be said, with low shear, warm to hot sea temps and strong radial outflow. With Nisha's rapid development so far, don't be surprised to see some further rapid intensification.

Nisha is expected to turn towards the east soon as it responds to the steering influence of an equatorial ridge. This should keep Nisha over warm waters for the next several days, meaning Nisha could become intense. Small islands lay in it's path, and inhabitants need to really closely watch Nisha.

[Cookie]

according to that very fast intensification expected soon.

[Somerset Squall]

Yes, and that forecast could well be conservative looking at the latest satellite image, and eye is forming already!

[Somerset Squall]

Nisha has strengthened to 50kts. The cyclone is moving quickly east-southeastwards and will soon move direcrly eastwards as a strong equatorward ridge sets in to the north of Nisha. Moderate shear has capped rapid intensification, though is not enough to stop Nisha gradually intensifying. Beyond 48hrs, shear may reach prohibitive levels and then weakening could occur. Waters are warm throughout the eastward forecast track, so Nisha should survive as a tropical cyclone for at least the next 5 days.

[Cookie]

thanks for the updates

[Somerset Squall]

High wind shear has set in prematurely, and has weakened Nisha to 35kts. Convection is displaced east of the LLC, indicating a weakening, sheared system. The cyclone has moved northeastwards over the last 6hrs, and will slowly continue in this direction until dissipation, which is now expected to occur within 48hrs. However, if convection doesn't relocate to the centre soon, Nisha may dissipate before then.

[Somerset Squall]

Nisha dissipated yesterday in high shear. Regeneration is not expected.