[surreal1221]

TWR controllers make the call. Actually, the supervisor on shift will make the call.

A number of factors that will play into it are the winds, time of day, etc etc. Each facility has their own SOPs that will dictate what conditions have to be met before they will switch runways. A majority of airports have a calm wind runway configuration, and for it to change, conditions must fall into another category of configuration.

It can be a headache. Just imagine a frontal passage, where winds out ahead of the front are from the SW, and after passage they shift quickly to the NW. Now imagine this wind shift during peak traffic at any number of Class B fields. Combined with the convection associated with cold FROPA, the STARs are getting messy (TRACON), holds are occuring (ENROUTE), and a shift occurs in the RWY config (TWR). All starting from the bottom up.

All in a days work.