Atomic Blue is advertised as an Electric Lemonade type of DEW flavor, similar to Lemon, Game Fuel (Lemonade), or Vibe. Unlike those other flavors, Atomic Blue is (as its name implies) blue in color rather than yellow.
Its flavor appears to be a sour lemonade, mixed with a flavor similar to that used in Blue Raspberry Slushies. How strong the lemonade or blue raspberry flavor is varies heavily by location.
Its tagline is "DEW with Electrifying Lemonade Flavor."
Atomic Blue was first leaked on a r/MountainDew Reddit post that was posted on February 21st, 2020.
Officially, it was first exclusively released to Kum and Go convenience stores on May 2nd, 2020 in the United States. It was also released at Sheetz convenience stores not long afterward.
- By coincidence, Berry Monsoon was leaked and released exactly two years before the date when Atomic Blue came out.