These maps shows the yearly total precipitation change across 2012 - 2015. The classification of these maps are equal interval. There are 5 classes with 17.94 inches as minimum and 60.11 inches as maximum. As shown in those four maps below, the annual total precitation increases in Iowa from 2012 to 2015. Actually, these was a drought in 2012. So, many places in Iowa during 2012 has low precitation. After that, the precitation trends to be better. Regarding the spatial pattern, except 2013, the precitation amount in the southern Iowa is generally larger than northern part. The reason of this pattern is unclear due to lack of other related data, but this might be becasue southern area is closer to the equator.
Those eight maps below shows the max and min temperature in Iowa across 2012 - 2015. The classification is equal interval for each of them. There are 5 classes in each classification. Generally, the southern area has higher average max and min temperature than the northen area, which might be because of the distance to the equator. Regarding the temporal pattern of max temperature, 2012 has a dramatically overall high max tempature across entire state, which is also a contribution to the 2012 heavy drought. After 2012, the max temperature in the Iowa spatial trends to be stable. The temporal pattern of min temperature in Iowa is also somehow stable except 2014. A large area of the northen Iowa has very low temperature.