The opposing wind, the Poniente, is a dry westerly or northwesterly wind that brings good visibility in the summer months – enough to see the coast of Africa from Tarifa. It’s not as frequent as the Levanter and generally a bit weaker. Outside the Strait, at Cádiz, the Poniente is a cool and humid flow that moderates the high temperatures of summer. East or west wind, cloud cover is very low across inland Spain during the summer dry season, averaging 15-20 percent everywhere beneath the shadow path between Cadiz and Málaga. Rainfall amounts to only a few millimetres in August (Table 1).

Topography along both coasts of the Alboran Sea also has a significant regional influence on cloudiness. The western end of the Alboran Sea is constrained by the Sierra de las Nieves on the Spanish side and by the Rif Mountains of Morocco on the south. While the terrain on the Spanish side has only a small influence on cloudiness, that on the Moroccan side has a dramatic impact. The coastline of Morocco forms a scooped or basin shape, capturing the easterly Levanter as it impacts the coast (Figure 5). The stratus cloud and the rare weather systems that move over the Alboran Sea occasionally pack up against this coast, pressing cloud against the Rif Mountains, which the cloud is unable to cross. The average August cloud amount reaches nearly 50 percent east of Ceuta in Figure 3. Sunshine observations at Melila average only 61 percent of the maximum possible, well below the 75 to 80 percent at many other locations along the track (Table 1). Cloud piles up against the Rif Mountains impacts the cities of Ceuta, Martil, and Tetouan, significantly reducinf the frequency of sunny hours at Melila and Al Hoceima in Table 1. In Spain, the terrain is most likely to produce convective cloud in the afternoon, sometimes in concert with weak summer cold fronts that sweep across the region and extend into inland Africa. On the Atlantic side of the Strait, and along the ocean-facing coasts of Spain and Morocco, cloud cover changes its character. The flow out of the Strait sometimes creates a “streamer” of cloud that may turn and hug the coast for a short distance to the north or south, but these are uncommon. More frequently, marine clouds or fog moves onto the Atlantic coast of Morocco, though it doesn’t penetrate far inland. Morning convective clouds buildups are common on the mountains and may turn into severe thunderstorms in the afternoon, but this should not be a major problem in the morning when the shadow passes. In spite of the impact of terrain and water, most cloudiness that affects North Africa is not local in origin. There is a moderate amount of mid and high-level cloud that arrives with weather systems that are familiar to Europeans and North Americans. Cold fronts from the Atlantic and Spain occasionally sweep southward across the eclipse track bringing bands of broken cloud from Morocco to Tunisia. The sub-tropical jet stream usually lies across Spain in August, but often dips southward to carry mid- and high-level cloud through the region. Saharan lows bring hot, dusty weather northward while small Mediterranean lows spread cloud and precipitation along the coasts and onto the shadow path. Thunderstorms frequently form on the mountains on either coast and spread cirrus and mid-level cloud downwind though, fortunately, are creatures of the afternoon and the eclipse is in the morning. Overall, however, such systems are infrequent and sunny weather dominates. Most of these larger weather systems will affect the early part of the eclipse track, from Tangier to Sfax, after which the coastline dips sharply southward and the track turns to the southeast, away from the temperate-zone storms and into the desert climatology.