Weather in a Pen Stroke

Before today’s technology was available, skilled technicians plotted cloud and atmospheric observa­tions on weather maps by hand. New observations arrived over telegraph or Teletype, and the plotter would create a new map each time. The information arrived in an alphanumeric code, and the plotter would have to decode and record the correct data at the location of each station. The information had to be entered quickly in order for the plotted map to be current. It also had to be entered in a universally accepted format, and it had to be legible so that the analyst could use the plotted map.