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The only tropical cyclone to have any influence on New Zealand weather during the 2000-01 season was Cyclone Sose. In mid-April this cyclone moved south from the subtropics towards northern districts and was eventually absorbed into a complex depression system moving onto the country from the Tasman Sea.

The humid, moisture-laden air associated with Cyclone Sose combined with the strong upward motion preceding the Tasman Sea depressions, bringing heavy rain over northern districts. The result was flooding and disruption, especially in Northland, Coromandel Peninsula and Bay of Plenty.

In Northland rainfalls of 200mm in 24 hours were recorded (12-13th April) resulting in flooding of roads and properties, notably in Kaio. Rainfall rates of 26mm per hour in Whitianga (on the Coromandel Peninsula) early on the 13th, and over 40mm per hour in Tauranga early on the 14th also produced floods.

The heavy rain was accompanied by gale force northeasterlies in many northern regions. Near Ohakune, 3 people were injured by a tent which collapsed in the wind. In Cook Strait, Lynx fast-ferry sailings were cancelled on the 13th due to southerly gales and heavy swell. In Picton, strong southerlies caused power-lines to arc, sparking a fire on the 13th which lasted into the 14th.

The wet, stormy weather contributed to numerous car accidents in northern districts, some involving fatalities.

Mean sea level pressure analyses for midday 12 to midnight 14 April 2001 NZST, in 12 hour steps respectively.

As seen in the maps, by midday 12 April Cyclone Sose had already moved out of the tropics and decayed into a small low 1000hPa, centred near 29°S 171°E, moving southeast 5 knots.

By midnight 12 April, the low which was Cyclone Sose was absorbed completely into the large, dynamic twin-centred low system approaching Northland from the Tasman Sea. The injection of tropical moisture from the old cyclone simply added to the intensity of the front and low system moving over northern New Zealand during the period.