During WWII, information about the weather played an extremely important role. The Army Air Forces were completely dependent upon intelligence regarding the atmospheric ?terrain? in which they operated. Accurate forecasts could determine whether a bombing target would be obscured by clouds or fog, or whether conditions were favorable enough for aircraft to fly. Weather forecasting detachments were present at nearly every major Allied airbase. Some weathermen even worked as special intelligence with the OSS (Office of Strategic Services), and performed weather information-gathering missions behind enemy lines.
The AAF Weather Service trained approximately 6,200 weather officers during WWII, including many WACs (Women's Army Corps) who were trained as weather observers.