Ballooning behaviour is a key trait in spiders, generally performed by juveniles, which allows dispersal from short to long distances. Although aerial dispersal can be risky, the avoidance of unsuitable conditions seems to overcome its potential drawbacks. Allocosa senex (Mello-Leitão, 1945) and A. marindia Simó, Lise, Pompozzi & Laborda, 2017 are two sympatric, nocturnal, wolf spiders, inhabitants of sandy freshwater and oceanic coasts of southern South America. We tested ballooning propensity of these species under natural conditions in day (d) and night (n) experiments. We collected adult females of A. senex, A. marindia and Schizocosa malitiosa (Tullgren, 1905) (control group) carrying spiderlings on their backs. We performed trials to test pre-ballooning occurrence of individual spiderlings as follows: 64 for A. senex (30d, 32n), 40 for A. marindia (20d, 20n) and S. malitiosa (31d, 32n). Both Allocosa spp. showed significantly higher frequencies of preballooning than S. malitiosa in both day and night trials. We did not find differences within species in pre-ballooning occurrence between day and night. Temperature, wind speed, humidity and atmospheric pressure were related to pre-ballooning frequencies during day and night in all species. We discuss the results in relation with microhabitat characteristics in such a dynamic environment.