"Pull down your pants and slide on the ice" is a M*A*S*H reference. It's a line spoken by the character Maj. Sidney Freedman.
Ralph calls Cicada's ability of flight "Supergirl-ing away," suggesting he's become aware of Team Flash's friendship with Kara Danvers, since in "The Elongated Knight Rises (2018)", he doesn't understand a reference to kryptonite.
References to previous episodes are mentioned including: Renee mentions watching a fight on the 6 o'clock news, between "A Giant Shark and a Giant Gorilla" referring to King Shark vs. Gorilla Grodd (2019). Barry remembers trapping Thawne in the containment cell in "Fast Enough" Fallout gets mentioned, referring to the events of Fury Rogue (2018). Ralph mentions that David Hersch was supposed to be Cicada in the original timeline, before Nora changed it, referring to The Death of Vibe (2018).
At 15:24 Ralph refers to "timey-wimey", an expression often used by Doctor Who.
The phrase; "hold on to your butts", said by Cisco Ramon/Carlos Valdez, is a line originally spoken by Ray Arnold/Samuel L. Jackson in Jurassic Park. This line was actually a direct quote said by Robert Zemeckis on the set of Death Becomes Her when he and his crew were pressed for time reviewing the dailies (the daily recordings/takes). The screenwriter; David Koepp, enjoyed the line so much that he wrote it into his next project; Jurassic Park.