The seemingly mindless act of swatting a mosquito on your hand poses a challenge for the brain. Given that the primary somatosensory cortex maps skin location independently of arm posture, the brain must re-align tactile coordinates in order to locate events in external space. Here we track the time course of how these externally-based representations are built using a crossmodal cueing paradigm. Participants held their arms crossed and performed a discrimination task on lateralised visual targets presented near the hands, after receiving a non-predictive tactile cue. During the first hundred milliseconds after the cue, reaction times to the lights were speeded up for anatomically congruent but spatially incongruent tactile cues. This pattern reversed after about two hundred milliseconds so that tactile cues produced a facilitation of targets presented at the same external location. When participants were asked to explicitly compare the location of tactile and visual events, they responded according to an external frame of reference, thus indicating no awareness of early somatotopic representations. These results reveal the time course of the dynamic remapping of tactile space, with early unconscious somatotopic representations giving way to the later external frame of reference that characterizes our conscious experience.