MINIMUM Temperatures.

Hi Sabine,

I have a sleeping bag for sale that will keep you comfy in these temperatures. Even long enough for you as I had it made for my length

Great explanation .Thanks!


It appears the  lowest  temperature that has  been recorded  in Southern Africa was  in  one  of the valley's  of Lesotho, just to the west  of the escarpment (near Sani Pass) This was due to the katabatic effect  (sinking  cold and dense  air) as well as the severe continental climate conditions  experienced in Lesotho being west of the escarpment,  It resulted   in  a temp of minus 21  . (I would treat the  minus  27  claimed by a lodge in Lesotho with  a bit of circumspection). The lowest temperature  ever recorded in South Africa  (and the coldest  place by far) is  not Sutherland,  but actually Buffeslfontein in the  Eastern Cape. A  reading  of minus 20 was recorded  there  during a severe cold front  in August 2013.

I'm not sure of the exact time and date of the temperatures reported from Afriski but these plots from the ECMWF model for 0400 UTC on 11 June map on very well. Minus 11 is widespread.

Weather forecasts have the potential to save lives these days. 

 

The dew point temperatures were extremely low with minimum dew points of around minus 26 deg C.
That is such incredibly dry air.

Coupled with the near winter solstice in solar radiation (solstice coming up next week), the dry air would have allowed extremely efficient long wave (infrared) radiative cooling. There is virtually no greenhouse gas in the form of water vapour to trap any heat.
So minimum (solar) radiative input, maximum loss of (solar) radiative input through reflection of sunshine off the snow, and maximum long wave radiative output leads to extremely cold temperatures.

 



The extremely low dew point temperatures in purple show up as the splodge over Lesotho. Nowhere in Africa, Asia or Europe had such dry near surface air that night.



 
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