2009 saw the beginning of Vortex 2, the largest tornado
While it may only be late April, the eyes of Western Cape residents are fixed on a strong cold front set to make landfall on Friday 22nd. While rain had already begun to fall around the coastal areas of the province on Wednesday night, the real action is still forecast to occur on Friday afternoon.
A low pressure system which currently lies to the south west of the country is forecast to strengthen, and pass to the south. Central pressure when moving past is forecast to be as low as 976mb, with Cape Town and parts of the south coast of the Western Cape seeing surface pressures which could dip below 1000mb. Seeing pressures below 1000mb at sea level is quite a rare event in the Cape. With this low central pressure, the main focus of this front will likely be swell and wind related.
Models are suggesting swell heights in excess of 8 meters possible around the Cape, and wind speeds sustained at around 60km/h with gusts possibly nearing 100km/h in places. Of course these outputs need to be taken with a pinch of salt and wind speed can vary significantly depending on location and elevation. Though it is safe to say that the models are forecasting the strongest storm of the year thus far for the Cape, and potentially one of the strongest in recent years if the model output were to materialize.
Gale force expected to reach 80-90 km/h between Table Bay & Cape Agulhas @ times moderating from evening whilst spreading to the South coast
— SA Weather Service (@SAWeatherServic) April 21, 2016
Aside from the large swell and hectic wind forecasts, good rainfall figures are also suggested by most the models with widespread rainfall in excess of 20mm likely, while other models suggest more aggressive rainfall figures in the range of 50mm in a short period, which could lead to localized flooding.
It’s always tough to forecast the exact specifics of these systems as any deepening, weakening, or change in positioning of the system could change the forecast. However at this stage, we’re certainly watching this system with eager attention to see what it may bring the Cape.
Forum Discussion: Weather Event – 21/22 April 2016