Elvis is seen with Louise Smith (the wife of his cousin Gene Smith) to the left and Arlene Cogan at right.
Elvis had just been named the movie star whose movies sold most popcorn and a proclamation had been issued that named him Honorary Kernel (Colonel) on the Mayor's Staff of Popcorn Village, USA.
He would receive a plaque (held by Louise in the pic) a few days later. The plaque read " In recognition of his CORN-spicious CORN-tribution toward the Progress, PrOPagation, POP-ularity and POPS-RITE-ness of POPCORN ..." and was dated March 19, 1958
So pic is from one of the very last days prior to his induction on March 24. Most likely March 20-21
Arlene Cogan wrote the very beautiful book"Elvis, This One's For You" about all the times she spent with Elvis from 1957 and into the sixties. Very recommendable reading.