Due to the Vietnam war, Johns served as an officer in the U.S. Coast and Geodetic Survey from March 1966 to late 1969.

Afterward, he returned to his meteorologist job with the USWB, taking a position at the forecast office in Kansas City, MO.

He was promoted to a SELS Assistant forecaster in 1974, and began issuing convective outlooks for the contiguous United States.

[2] Johns furthered forecasting techniques and developed the modern conceptualization of the derecho following landmark work on "northwest flow" severe weather patterns.

[1] Johns was recognized for his exemplary public service and received a number of honors for outstanding performance.