Seasonal and weather influence on the incidence of cerebrovascular disease has been reported previously. The aim of this retrospective study was to determine whether the time of onset of ischemic strokes (IS) and intracerebral hemorrhages (ICH) were associated with the environmental temperature or the time, as a month or season, in our region. We analyzed the monthly and seasonal incidence of stroke between 1997 and 2001. Four hundred and fifty-one cases were admitted to our. clinic (IS; n = 288 and ICH; n = 163), and aged from 16 to 94 years. The study was carried out in province of Van in eastern Turkey. The present study demonstrated a peak occurrence of IS in August (n = 41). For ICH, we observed a peak occurrence in July (n = 23). The highest number of IS occurred in summer (n = 108), the most moderate amount in autumn (n = 81), and the least in spring (n = 38). The hemorrhagic events were hi-hest in summer (n = 58), most moderate in winter (n 61), and lowest in spring (n = 31) and autumn (n = 32). There Was a significantly greater incidence of IS and ICH during the summer than any other season in the province of Van, Turkey. This may reflect the role of weather temperature in the development of stroke and allow us to take preventive measures.