As Autumn approaches us here in the Southern Hemisphere, Spring
The past week saw a strong cold front making landfall over the Western Cape and then proceeding move in an easterly direction where it also managed to cause temperatures to drop low enough for snow on the Eastern Cape mountains as well as the KwaZulu-Natal midlands. The town of Kokstad had minimum temperatures of around -3 with maximums just reaching about 6 degrees. Temperatures on Friday morning the 27th May 2011 in Johannesburg dropped down to single digits and saw residents sacrificing the warmth of their hands to tweet and update their facebook statuses on just how cold the morning was.
Snow is not that uncommon in May and it would most certainly appear that winter has now become settled, right on time too.
Looking ahead at the models it looks like a very week 2 or so weeks coming up for Cape Town and even parts of the Eastern Cape and Kwazulu Natal, though for the most part many of the cold fronts will not bring rain to the Gauteng area.
There are a total of 6 cold fronts forecast to make landfall in the Western Cape over the next 15 odd days, of which 1 of them appears to be a weak front, the rest all likely to bring down temperatures and bring some decent rains.
The most interesting of the systems shown by the latest GFS model run as of 16:00 on Friday 27th May is the approach and landfall of a large cut-off low pressure system which arrives around the end of the first week of June. The GFS is showing this cut off low bringing rain to almost all parts of the country extending from the south right through to the northern parts of the country. The cut-off low has an estimated central pressure of around 1004 so it’s not that deep, so wind associated with the system won’t be as bad as often the case with winter cut-off lows.
These model projections are still far out and are almost certain to change over the next few days and weeks, so stay tuned for updates on these outputs.