Reprinted by permission.Figure 10.31 Interaction between the westerlies and the tropical easterlies leading to the production of Saharan depressions (D), which move northeastward along a trough axis.Source: After Nicholson and Flohn (1980), copyright © 1980/1982 D. Reidel Publishing Company. Within these troughs, the subtropical jet stream meanders equatorward, accelerates (particularly in winter, when it reaches an average velocity of 60 ms-1 compared with a mean annual value of 39 ms-1) and generates upper-air depressions, which move southeastward along the front (analogous to the systems in North Africa). The eastern lee areas have much lower amounts, with less than 500 mm in some parts. Over most of the central Sahara, the mean annual precipitation is less than 25 mm, although the high plateaux of the Ahaggar and Tibesti receive over 100 mm. West- or northwest-facing mountains receive an average annual precipitation in excess of 2500 mm, with some parts of South Island exceeding 10 000 mm (see Figure 5.15). Over both oceans, the frequency of anticyclonic centres is greatest in a belt around 30°S in winter and 35-40°S in summer; they rarely occur south of 45°S.Between successive anticyclones are low-pressure troughs containing inter-anticyclonic fronts (sometimes termed 'polar') (Figure 10.33). Their most southerly track (38.5°S) is taken in February. Water temperatures are warm and ideal for swimming. Figure 10.34). The summer months in South Africa bring about hot, tropical weather throughout much of the country, making for great getaways in December, January, and February. Below are temperatures expected tomorrow at popular destinations in The 5-day weather forecast for North Africa is provided by the Swiss meteorological agency, Get your weekly fix of holiday inspiration from some of the world's best travel writers plus save on your next trip with the latest exclusive offersGet your weekly fix of holiday inspiration from leading travel writersNew airline routes & holiday destinations for 2020/2021Barcelo sale: up to 35% off hotels in Europe & beyondBarcelo sale: up to 35% off hotels in Europe & beyondWhere to go on holiday in August for the best weather9 of the best travel magazines to get you through lockdownWhere to go on holiday in April for the best weatherWhere to go on holiday in February for the best weather North Africa weather forecast. Summers in Southern Africa can be be quite hot, especially along the coastal areas. The variation in strength of the continental anticyclones and the passage of inter-anticyclonic fronts cause periodic inflows of surrounding maritime tropical airmasses from the Pacific (mTp) and the Indian (mTi) oceans. In autumn, high-pressure conditions increase in frequency up to 22 per cent, giving a drier season.Simple troughs with undeformed cold fronts and relatively simple interactions between the trailing and leading edge conditions of the anticyclones persist in about 44 per cent of the time during winter, spring and summer, compared with only 34 per cent in autumn. Inland in the higher elevations, temperatures do moderate. Værvarsel for 9,3 millioner steder i verden! Get your 3-Day weather forecast for Rustenburg, North-West, South Africa. The dominance of high-pressure conditions in the Sahara is marked by the low average precipitation in this region. However, twenty-four-hour storm rainfalls approaching 50 mm (more than 75 mm over the high plateaux) may be expected in scattered localities. helping us to finance a high quality free-of-charge precision weather service. Wave depressions occur with about the same frequency. Relief, especially the Southern Alps, predominantly controls rainfall amounts. Parts of western Algeria have gone at least two years without more than 0.1 mm of rain in any twenty-four-hour period, and most of southwest Egypt as much as five years. Over most of the central Sahara, the mean annual precipitation is less than 25 mm, although the high plateaux of the Ahaggar and Tibesti receive over 100 mm. Below are temperatures expected tomorrow at popular destinations in North Africa. It usually receives 3–7.5 inches (76–190 mm) of rain each year. The eastward rate of anticyclonic movement averages about 570 km/day in May to July and 780 km/day in October to December. The 5-day forecast shows the prevailing weather conditions, maximum & minimum temperatures, hours of sunshine per day, wind speed & direction and more. Rainfall is sparse and summer temperatures run high. Anticyclones, separated by troughs associated with cold fronts often deformed into wave depressions, cross the region on average once a week. On the eastern (leading) edge of the high-pressure cell the airflow is usually cool, maritime and southwesterly, interspersed with south or southeasterly flow producing drizzle. North Africa takes in roughly 10 countries, depending on where you draw its borders. Reprinted from D. Martyn (1992) Climates of the World, with kind permission from Elsevier Science NL, Sara Burgerhartstraat 25, 1055 KV Amsterdam, The Netherlands.rainfall intensities occurred in the vicinity of west-facing slopes in Algeria, such as at Tamanrasset (46 mm in sixty-three minutes) (Figure 10.30), El Golea (8.7 mm in three minutes) and Beni Abes (38.5 mm in twenty-five minutes). Cape Town is also quite windy at this time. Click "Accept and continue" to accept all cookies, or click below, to change your cookie settings.