Baja Flash was officially described as a Pineapple Coconut/Pina Colada flavor, similar to flavors such as Maui Burst. It was light yellow in color.
Its tagline was "DEW with a Blast of Natural & Artificial Pineapple Coconut Flavor."
On April 20th, 2020, PepsiCo filed a trademark for Baja Punch titled "MTN DEW BAJA PUNCH". On that same day, another trademark was filed for Baja Flash titled "MTN DEW BAJA FLASH".
On August 4th, 2020, an anonymous individual on the Dew Drinker Discord leaked official branding for the flavor, along with Baja Flash, Gingerbread Snap'd, Major Melon & its Zero Sugar variant, Riddler's Brew, and DEW-S-A.
On October 8th, 2020, a leaked internal reel video surfaced, showing upcoming plans for the Mountain Dew brand for 2021. This video reaffirmed much of the previously-leaked information for 2021, with new flavors including both seasonal flavors, such as Baja Flash, Baja Punch, Riddler's Brew, and Gingerbread Snap'd, as well as a new permanent flavor, Major Melon. This video also confirmed a promotion with these Baja flavors, calling it "100 Days of Baja."
Officially, it was released in stores in the United States on June 12th, 2021 for a limited time alongside Baja Punch, and was sold in 12-packs and and 20 ounce bottles. Both flavors stayed on store shelves until September 2021 when the 100 Days of Baja promotion ended and they were discontinued.
Around early 2021, Canadian PepsiCo filed trademarks for both Baja Flash and Baja Punch, although there was not much known about it at the time.
In late May 2021, Circle K began to advertise for Baja Flash alongside Baja Punch in 473mL (U.S. 16-ounce) large cans while also showing them in an unusual large can 12 pack. A week later, in June, Reddit users began to post that they have been finding them at select Circle K stores.
Likely because of low sales, Baja Flash was not produced in 20 oz. bottles unlike its counterpart Baja Punch.