Mayday! I mean M'aidez! No, wait, I mean, Pan, Pan, Pan!
The origin of the emergency call "Mayday! Mayday! Mayday!" comes from an anglicized version of the French "M'aidez" ( M' = Me; Aidez = Help, i.e. "Help me") and has nothing to do with the month of May.
Here's the right way to signal distress from boats.com —
Mayday Calls -- The right way to use this vital distress signal
by Chris Caswell
Use the word "Mayday" only when you and your boat are threatened with
"grave and imminent danger." A distress call consists of the word
Mayday repeated three times, the name of your boat, and the call sign:
"Mayday, Mayday, Mayday, this is Intrepid, WYV699."
Follow this immediately with the distress message, which includes the
word Mayday and your identification, your position, the nature of the
emergency, the number of people aboard and any other information to
speed your rescue: "Mayday, this is Intrepid, WYV699, 10 miles due west
of Point Angel, taking on water rapidly, cannot stay afloat more than 30
minutes, four persons on board, Intrepid is a 24-foot sportfisher, white
hull, blue trim. Maintaining watch on Channel 16. Intrepid, WYV699, over."
If your crisis is not life-threatening but you need to break through, use the
words "Pan, Pan, Pan" (the urgency signal for assistance) before your
call: "Pan, Pan, Pan, this is Intrepid, WYV699, have apparent broken arm
aboard, need medical advice immediately, Intrepid, WYV699, over."
I find it hard to believe "Pan, Pan, Pan!" would do much for anyone shouting it out.