Tropical Cyclone HARUNA in the area of in February 2013 Dr. Susanne Haeseler; updated: 26 February 2013

Introduction and storm track

On 20 February 2013, the HARUNA had formed across the Channel, the sea area between Africa and Madagascar (Fig. 1, 2 and 3a). On its way to the southern part of Madagascar's west coast, speeds (1 minute aver- age) up to about 100 knots (185 km/h) were reached. This is equivalent to a category 3 hur- ricane on the 1 to 5 rating Saffir-Simpson hurricane scale.

On 22 February at about 02:30 UTC, the tropical cyclone made about 55 km south of Morombe and crossed southern Madagascar while weakening (Fig. 3b). Heavy precipitation triggered by HARUNA caused regionally serious floods, and high wind speeds contributed to severe damage. Media reported of at least 10 deaths.

In the early morning of 23 February, after having crossed the island in about 24 hours, the storm centre reached the eastern coast of Madagascar (Fig. 3c). East of the island, HARUNA re-strengthened to a tropical storm (tempête tropicale) for a short time, and then dissipated by and by.

Fig. 1: Map of Madagascar and surroundings with stations mentioned below.

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Fig. 2: Track of tropical cyclone HARUNA. Observation (solid line) and forecast (dashed line) on 24 February 2013. [Source: Meteo France; supplemented]

2 Wind and precipitation

On Ile Europa, an island in the Mozambique Channel being affected by HARUNA, a mean wind speed (10 minute average) of 83 km/h (45 kn) was recorded on 20 February 2013, 12 UTC. Between 06 and 18 UTC that day, 204 mm of rain poured down there, with 148 mm in only 6 hours (between 12 and 18 UTC), and additional 57 mm during the following 6 hours.

Fig. 3a: Satellite image of tropical cyclone HARUNA across the Mo- zambique Channel on 21 February 2013, 12 UTC. [Source: Meteo France]

Morombe, a city on the south-western coast of Madagascar, reported a precipitation total of 166 mm falling within 6 hours from 21 February, 18 UTC, to 22 February, 00 UTC. Besides, the windiest conditions occurred overnight 21st/22nd with a mean wind speed (10 minute average) of 65 km/h (35 kn).

Fig. 3b: Satellite image of HARUNA across Madagascar on 22 February 2013, 18 UTC. [Source: Meteo France]

Ashore, HARUNA continued causing heavy rains of regionally about 50 mm and more within 6 hours. In Tolanaro (also Tolagnaro; formerly Fort Dauphin), in the south of Madagascar, where HARUNA arrived much weakened, a 24-hour precipitation total of 187 mm was re- corded for the period from 22 February, 18 UTC, to 23 February, 18 UTC.

3 Fig. 3c: Satellite image of HARUNA across south-eastern Madagascar on 23 February 2013, 06 UTC. [Source: Meteo France]

Sources

. Deutscher Wetterdienst (DWD): Data archive. . Meteo France, Reunion: Suivi Cyclonique. http://www.meteo.fr/temps/domtom/La_Reunion/meteoreunion2/ . NOAA, National Hurricane Center: Saffir-Simpson Hurricane Wind Scale. http://www.nhc.noaa.gov/aboutsshws.php . Unisys:2013 Hurricane/Tropical Data for Southern Indian Ocean. http://weather.unisys.com/hurricane/s_indian/2013/index.php . WMO: RSMC Marine Warning. http://severe.worldweather.wmo.int/tc/swi/pop-ups/tc/lr_44201302222.meta . WMO, Severe Weather Information Centre: http://severe.worldweather.wmo.int/

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