The first official tornado forecast—and tornado warning—was made by United States Air Force Capt. (later Col. ) Robert C. Miller and Major Ernest Fawbush, on March 25, 1948. The first such forecast came after the events that transpired five days earlier on March 20, 1948; Miller – a California native who became stationed at Tinker Air Force Base three weeks earlier – was assigned to work the late shift as a forecaster for the base's Air Weather Service office that evening, analyzing U. S. Weather Bureau surface maps and upper-air charts that failed to note atmospheric instability and moisture content present over Oklahoma that would be suitable for producing thunderstorm activity, erroneously forecasting dry conditions for that night. Thunderstorms soon developed southwest of Oklahoma City, and at 9:30 p. m. , forecasters from Will Rogers Airport sent a warning to Tinker that the storm encroaching the city was producing wind gusts of 92 miles per hour (148 km/h) and a "Tornado South on Ground Moving NE!" Base personnel received an alert written by the staff sergeant on duty with Miller, minutes before the twister struck Tinker several minutes later around 10:00 p. m. , damaging several military aircraft (with total damage estimated at $10 million) that could not be secured in time before it crossed the base grounds.