Tropical Cyclone Herman 2023

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Satellite images, weather maps and tracks of Category 5 Tropical Cyclone Herman 2023, March 27 - April 3. Max wind speed 235km/h.

Herman is located 924 km west-northwest of Learmonth, Australia, and has moved westward at 11 km/h (6 knots) over the past 6 hours.

Satellite imagery shows organized banding with very little convection wrapping into a low-level circulation center (LLCC). Radar, along with an ASCAT-B pass, both show a small patch of 65 km/h winds (35 knots) in the western semi-circle with 35-45 km/h winds (20-25 knots) dominating the rest of the wind field.

The system albeit small, some would say pee-wee, Herman is undergoing dissipation at an impressive, expedited rate similar to how it rapidly intensified on march 30th.

Herman is in an unfavorable environment for further tropical development. These conditions are characterized by weak outflow aloft, strong (25-30 knots) wind shear, and cooler (24-25°C) sea surface temperatures.

The initial position is placed with high confidence based on multi-agency fixes, as well as the aforementioned satellite imagery revealing the exposed LLCC.

The initial intensity of 65 km/h (35 knots) is assessed with high confidence based off the previously mentioned ASCAT imagery. Herman is riding the western edge of the subtropical ridge to the east-northeast.

As it continues this trajectory, Herman will fill rapidly as all of its mid-to-upper level support will continue to dwindle due to the harsh environment.

An approaching major longwave trough from the west will absorb the remnants of Herman over the course of the next couple of days. The deterministic and ensemble models all agree that Herman will continue to fill as it transits to the northwest before it completely dissipates after 24 hours.

This is the final warning on this system by JTWC. The system will be closely monitored for signs of regeneration.

Maximum significant wave height is 5.2 meters (17 feet).

Information provided by the Joint Typhoon Warning Center (JTWC).