The climate is influenced by macro-global geological phenomena: Situated on the Schapenberg ridge some 300m above sea level E18°54 and S34°06’ at 7.5km distance from the Atlantic Ocean and Falsebay it can be concluded that our vines are cooled by the Antarctic. Jet streams and global winds result in oceanic movements and currents. The Benguela current carries ice cold water from the Antarctic to the Cape and into False Bay. From there chilled winds reach the farm.
The climate of the area is Mediterranean with warm, dry summers and cold, mildly wet winters. The Koppen climate classification for the area is Csb – mild, humid climate with warm, dry summers.
The area is subject to cold fronts in winter associated with low-pressure cells, which intensifies with the progressive uplift on the approach to the mountains. During summer when high-pressure anticyclonic cells migrate towards the Cape, southeaster conditions occur. In the lee of the mountains and especially in the Sir Lowry’s Pass area, persistent gales develop. At the higher elevations heavy orographic clouds condense precipitating fog (Cummings, 1997). Strong southeastery gales prevail in summer and strong northwesterly winds in winter. See Appendix for maps with wind roses for winter and summer. (Weather Bureau, 1965)
Climatic data from the farm is unfortunately not available. The closest weather data obtainable is from the Steenbras Dam (34 11′ south, 18 51′ east ). However, a weather station has been purchased for the farm, not only for general recording purposes, but also for efficient farming management (applying pest-, weed-, and fungicides at the right time). It will take at least one year to get some reliable information for estimates and at least a few years of data to really be able to compare differences in microclimates to other ones in the region.
For now the information from Steenbras Dam station is used. Rainfall measurements for the 25 year period up to 1960 shows a clear pattern of winter rainfall with 75 % of the average of 840mm per year falling in during April to September. Summer rainfall (October – March) only contributes 25% to the annual rainfall (Weather Bureau, 1954). It is clear that the period October to March is the period limiting plant growth.
The area has hot summers with the average monthly maximum temperatures in summer ranging between 28.1 and 32.8 degrees Celsius and an absolute daily maximum temperature of 37.2 degrees Celsius measured. Winter average minimum temperatures range between 2.4 and 7.3 degrees Celsius and can therefore be considered as mild. The absolute lowest minimum daily temperature measured was –1.1 degrees Celsius. Snow, hail and thunder are not important climatic parameters in the area with an average of only 5 days of snow per year, in winter and early spring.