It’s been a quiet summer as far as trough activity
The month of May is here, April and May have historically been some of the more interesting months for weather in the Cape Town area. The upper air patterns are more supportive for cut-off low pressure systems impacting the Western Cape. This year has proved thus far to follow along the lines of previous Autumn months. An upper air trough on Monday May 2nd brought showers and thundershowers to the Cape Town area along with some heavy falls of rain. Around 7pm on Monday night the sky became active with a decent lightning show along with some flash flooding taking place in the Strand and Somerset West area.
Looking ahead at the models it seems that it’s not over yet, in fact it may just be beginning (the thundery weather). Another trough looks likely to impact Cape Town tomorrow 5 May 2011 which is likely to bring more showers and thundershowers and also has the potential for some good rainfall figures. The South African Weather Service is forecasting 60% chance of showers and thundershowers with around 10mm of rain, which is quite a lot for a trough and could easily be more than that.
There is also the possibility of a cut-off low pressure system at the beginning of next week. The trough will move south on Saturday and Sunday, with some action possible even on Sunday night, though Monday and Tuesday is where the SAWS is forecasting majority of the rainfall and thundershowers to take place. These systems can change drastically and with the low still being a week out, the forecast holds very little confidence. Though the potential definitely exists for something to happen. Fluctuations in these systems can mean no rainfall, to 50mm rainfall. It will likely change before the weekend arrives, whether it will mean less or more, in terms of rainfall – that is as good as anybody’s guess.
Keep an eye on your local forecasts and model runs though, this is May after all!