Another cold-front and sharp upper trough is likely to reach the SW-Cape on Sun 5th, before moving along the Cape coast, and reaching the Drakensberg by Mon 6th. More than usual amounts of snow, at lower than usual elevations are shown by current model runs (GFS and NOGAPS up to 00Z on Thurs 2nd). Earlier model runs indicated the possible formation of a strong cutoff-low along the KZN coast on Tues 7th, though this now seems less likely.
As usual with this kind of system, there is still considerable uncertainty at longer durations (4-5 days), particularly in the position of the South Atlantic High pressure cell. The models also show another frontal system making landfall on Thurs 9th (7 days ahead), and the close spacing of the two systems can reduce certainty in developments over KZN on Tues 7th (5-6 days ahead).
The NCEP custom GFS charts are broken this morning (Thurs 2nd), and the NCEP ensemble might also not update today, so I can't post many images yet. The site snow-forecast has updated, and gives an excellent animation of the likely outcome: www.snow-forecast.com/maps/dynamic/southafrica
P.S. It's hard to come up with names for the never ending series of cold-fronts arriving this winter, since they all have some things in common, but each is slightly different (depending on your location relative to the postion of the storm).
Compiled by Gordon Richardson (StormchasingSA)
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