This is an exciting catch: the most distant mediumwave station I've ever heard, and the first Asian one too. Station: BSKSA (Broadcasting Service of the Kingdom of Saudi Arabia) from Duba, Saudi Arabia on 1521 kHz at 0236 UTC. Signal was fair to poor: fairly strong but some fading and co-channel interference from WWKB 1520 (Bufallo, NY). Programming was talk in Arabic and some singing.
I'm classifying this one as tentative-but-probable. No ID was heard, but as far as I can tell there are no Arabic language stations on 1520 in North America, esp. at night; this was also definitely on 1521; and there are no other Arabic stations listed in Europe, Africa, or Asia, BSKSA on 1521 transmits at an incredible 2 MW of power (2000 kW) making it 40 times more powerful than the most powerful stations in North America, and it is a regular catch by DXers along the east coast of North America.
Today's listening location: a bed-and-breakfast in York Harbour, NL (on the Bay of Islands west of Corner Brook). The first place I've stayed in since Rocky Harbour where there was no electrical interference on AM (at least after everyone went to bed).