Storm Chasers / Spotters Database It is an ambition
It seems that South Africa, and in particular the Western Cape, will begin to finally experience weather conditions fitting to the season. The months of March through May have been excessively dry, resulting in shortages of dam water in several areas, as well as the drying up of several vleis. It seems that winter may have finally caught up with the calendar though, as the models suggest some interesting weather developments over the next week.
Please note that this forecast is still almost a week away and due to the volatile nature of cut-off low forecasts, there is still a lot of room for change at this period.
Even though some weak cold fronts have brought some showers to the Cape over the past few days, the main rain events will start with the first cold front arriving on Friday evening when a large cold front approaches the Western Cape. This front, despite covering a large area – will remain quite far south and mostly brush the province, as it then spreads showers along the east coast of South Africa. Probably the most noteworthy aspect of this particular system is the linger showers and cold temperatures that will persist in the wake of the front on the Sunday, as a high pressure system pushes in from the west. Despite surface temperatures likely being in the low teens for much of the Western Cape on Sunday, snowfalls are not likely and the freezing level looks to remain at around the 2000m mark during the peak cold period. Despite rain expecting to begin clearing around Cape Town on Monday, the front is likely to continue bringing rain to the eastern coastal areas into the week.
Now for the really interesting stuff…
Eyes turn to the west coast on Tuesday as a cut-off low develops around the South African / Namibia border. It then waxes and wanes in strength, as it moves southward towards the Western Cape. Earlier model runs showed this cut-off low remaining strong and strengthening as it moved south, however the most recent run (06z 27 May 2015), shows the system opening up into a trough a few times, never really strengthening much. Despite the inconsistencies shown over the past couple days, the same scenario of a cut-off low impacting the Western Cape seems quite possible. We will have to wait and see what future runs show with regards to the exact nature, but it’s possible that we could be looking at our first heavy rain event in quite some time. The models would suggest rainfall of over 20mm possible through Wednesday and Thursday. From Thursday into Friday, the low is expected to move more east and with it, bring the possibility of heavy rain into the central interior of the country, potentially affecting the Northern, Eastern and Western Cape.
For those hoping for snow, this cut-off low is unlikely to bring any with it and forecast temperatures will remain fairly mild. If anything, this will be a rain making event.
Updates will be made accordingly depending on how the situation develops over the next few days.