Across
Unit no longer used flag with name when temperature dropped (14)
I haven't cracked this one yet — but Fifteensquared have:
STANDARD (a flag) + [h] ANDLE (slang for name, especially a pseudonym), with H replaced by C (hot to cold = temperature dropped). An old name for the candela, a unit of luminous intensity. (Or an astronomical object of known brightness, used as a standard to estimate the distance to similar objects, but I’m not sure that really meets the definition “unit”.)
Drags around European and goes downhill quickly (5)
I haven't cracked this one yet — but Fifteensquared have:
LUGS (drags = pulls a heavy object along the ground) around E (abbreviation for European). Luge, as a verb = to take part in a winter sport that is one of many variations of sledging, specifically going down a track feet-first lying on your back.
Don't be so foolish as to deny being foolish (8)
Briefly explains horticultural shows (7)
Before a party rent Twister (7)
Strip card game not starting (5)
Cause to be joyous as European Community stagnation ending in June (9)
Leader may fancy fast food? (9)
American branch of organisation is proficient (5)
Bitterly discontented try to get bit of TLC off Pat (7)
I haven't cracked this one yet — but Fifteensquared have:
B [itterl] Y (dis-contented = inner letters removed) + HEAR (try = judge a case in court) + first letter (a bit) of T [lc]. The idea of a bit = first letter is common enough, though it’s unusual to see it applied to an abbreviation rather than a real word. Off pat = by heart = from memory rather than referring to a script or notes.
Essentially many argued old fart is lacking grace (7)
I haven't cracked this one yet — but Fifteensquared have:
Middle letter or letters (essentially) of [m] AN [y] [ar] GU [ed] [o] L [d] [f] AR [t]. Angular = awkward = lacking grace.
Call Yank to get can opener (8)
Second journalist found in hut (5)
Dodgy character stole big car (14)
Down
Beach-dwellers bail Red Cross out (12)
Scotsman's right to replace new guardian (5)
I haven't cracked this one yet — but Fifteensquared have:
A [n] GUS (Scottish man’s name), with the N (abbreviation for new) replaced by R (abbreviation for right). A guardian: from a giant in Greek mythology who had a hundred eyes and was ordered to watch over Io.
Extremely supportive of dance breakthrough? (9)
Went up primarily to trial election affiliation indicator (7)
Forms in English hidden in boxes (7)
Unpaid Piers regularly gets to all-time low (5)
I haven't cracked this one yet — but Fifteensquared have:
Alternate letters (regularly) of [u] N [p] A [i] D [p] I [e] R [s].
Spitting image of King John at the top the greatest King on earth (9)
Develop way with less money to get mediator (12)
Desire for end with a shed reconsidered (9)
22 struggling in eastern lands to provide pain relief (9)
Inspire P&O to abandon luxury accommodation (7)
Perhaps circular field fine to rent out (7)
Financial backer of a Northern setter (5)
The French likely to get jumped (5)
Type letters or click words in the clue