Final answer:
City W is most susceptible to landslides, given its combination of warm temperatures with heavy rains, which can lead to soil saturation and increased likelihood of landslide events.
Step-by-step explanation:
Based on the weather data for the four cities over the last three days, the area most likely to experience landslides is the city that has had warm temperatures with heavy rains. Heavy rainfall can saturate soil, reducing its cohesion and increasing the likelihood of a landslide, especially in areas with variably elevated terrain. Warm temperatures further exacerbate the situation by increasing the likelihood of snowmelt in elevated areas, adding to the water saturation. While the relief map showing elevation is not provided here, regions with steep slopes or hilly terrain that have experienced heavy rainfall are typically at higher risk for landslides. Therefore, among the four cities, the one that has warm temperatures with heavy rains (City W) is most susceptible to landslides.