The climate is semiarid in moisture and subtropical in temperature. Humidity is more often high than low, with periodic morning fog due to Gulf air masses moving northwest into the area. This gives Del Rio and adjacent areas the effect of being in a coastal dryland area, though the Gulf of Mexico is over away. Such humid periods alternate with periods of hot and dry desert air masses in the spring and fall, or cold and dry Great Plains air masses during winter. Moisture rarely lasts long enough for weather systems to react with it to create much precipitation, as happens more frequently to the north and east of the area; some exceptions occur during some autumn (tropical weather systems) and spring (stalled fronts to the north).