Wikipedia
Wettererkundungsstaffeln (also known as Wekusta or Westa) were flying units of the Luftwaffe of squadron strength used for weather reconnaissance. Their primary task was to collect weather data in areas that only aircraft could penetrate.
For the planning and conduct of military operations, the ability to produce accurate weather forecasts can be a decisive factor. However, international weather data required for this purpose were not readily available to the German military at the time of the Second World War. The Wehrmacht therefore created a global network of weather stations, weather ships and weather aircraft. The weather aircraft were organised into special squadrons and were usually directly subordinate to the Luftwaffe or Luftwaffenführungskommando. Overall, there were eleven Wekustas, each of which had between three and twelve two-engined aircraft. Many meteorologists were conscripted into the squadrons to collect the weather data and more than 200 of them were killed.