Torrential downpours, similar to the more famous monsoons, occur frequently in the Valle de la Ermita during the rainy season, leading to flash floods that sometimes inundate the city. Due to these heavy rainfalls, some of the slums perched on the steep edges of the canyons that criss-cross the Valle de la Ermita are washed away and buried under mudslides, as in October 2005. Tropical waves, tropical storms and hurricanes sometimes strike the Guatemalan highlands, which also bring torrential rains to the Guatemala City region and trigger these deadly mudslides.