 Ramba uchinyora ndima ino - Gungwa racho riri mukati medziva rakakura re2.5 x 1,750 km, rakaumbwa nemhepo yemvura uye kunyange mhepo yechando, iyo inenge yakazara zvachose. Ndiwo mugumisiro wechiito chechando uye mistral pakupera kweRiss glaciation. Nzvimbo yemvura inogara iripo, pamwero unoshanduka, naizvozvo ine nzvimbo inochinja-chinja yakaenzana, inopiwa nguva dzose nemishonga yemvura yakasviba. Icho chikamu chemaguta eIstres, Saint-Mitre-les-Remparts uye Fos-sur-Mer, maererano nemuganhu wakachengetwa mumagwaro emunharaunda eSaint-Miter, musi waApril 15, 1551. Rwakapoteredzwa kumabvazuva nokumavirira nezvikomo zvakafukidzwa nemasango emiti nemiti yemapine. Kumaodzanyemba nokuchamhembe, kune masango akareba uye masango ari pedyo nemhenderekedzo dzegungwa. 