Tropical Storm Dineo was intensifying in the middle of the Mozambique Channel when NASA’s GPM core observatory satellite flew over on February 14, 2017 at 0926 UTC. Heavy rainfall of 100mm to 200mm per day is being forecast for southern Mozambique and parts of South Africa as they are hit by the formidable storm system.
South African Weather Service chief forecaster Kevin Rae said that Dineo‚ classified for now as a Severe Tropical Storm‚ would gather strength as it reached the coast of Mozambique late on Wednesday evening‚ near Massinga‚ north of Inhambane.
“Dineo is also quite likely to undergo a final surge of intensification‚ just before arriving over land and there is a good chance that it will reach Tropical Cyclone status‚” he said in a weather update.
The storm was positioned in the Mozambique Channel in the early hours of Wednesday moving at about 14km/h.
“Given that Dineo is likely to reach Tropical Cyclone intensity during today‚ the projected maximum strength of surface winds associated with the system will be 70 knots‚ or about 130km/h. Whilst this wind strength is somewhat weaker than the earlier estimate of 160 to 170km/h‚ this is still a formidable storm system which has the potential to cause much damage to coastal and inland infrastructure‚” said Rae.
Communities in southern Mozambique will be vulnerable to torrential rain and flooding.
Sea conditions along the southern Mozambican coast will be very rough – of the order of six to eight metres. There is an additional threat of a marine storm surge along the coastline north of Xai-Xai.
He warned that southern Mozambique would experience “very heavy rainfall‚ most likely in the region of 100 to 200mm per day‚ or even more”.
South Africa will experience heavy rainfall over the northern lowveld and adjacent escarpment regions of Limpopo on Thursday evening.
Rae said the greatest impact was likely overnight on Thursday when “heavy rain can be expected over the entire eastern half of Limpopo‚ including the Kruger National Park‚ where 100 to 200mm of rain could occur per day.”
Dineo was expected to dissipate in the region of Musina and Beit Bridge on Friday and drift towards Botswana by Saturday.
Tropical storms and cyclones‚ which originate over open water‚ weaken significantly as they pass over land. This‚ said Rae‚ was because they depended on the open ocean as a source of latent heat energy to sustain their growth and intensification.