Cold-front and snow SW&S-Cape 21-23 September 2012

Unlike the past weekend (Sat 15th & Sun 16th), which had glorious sunshine (and 30C temperatures) over Cape Town, the upcoming long-weekend (Heritage Day/Braai Day on Mon 24th) will get off to a cold start. Those who had hoped for beach weather (at least over start of the weekend) will be sorely disappointed!?

Numerous model runs and forecasts show another late-winter cold-front and sharp upper trough is likely to reach Cape Town late on Thurs 20th. This will bring heavy rain on Fri 21st, with possible snow over the SW&S-Cape mountains on Sat 22nd, clearing very slowly on Sun 23rd. The current SAWS forecast is for 24mm of rain on Fri 21st, and temperatures below 20C for the weekend (Sat 22nd & Sun 23rd).

This custom GFS chart shows the likely rainfall (mm/day) during the 12 hours from 00Z to 12Z on Sat 22nd, along with the freezing level at 06Z.

Compiled by Gordon Richardson (Stormchasing SA)