I'm a teeny bit confused. The strong source of HF-FAX transmissions that i've been recording and decoding is broadcasting at night on 8.502 Mhz. I thought (based upon some link i can no longer find) that the transmissions were coming from Australia. But this website which has a list of HF-FAX transmitters suggests that it's coming from Norfolk, VA.
There seems to be some genuine confusion. But for now, I'm going to assume it's Norfolk, not Australia.
Addendum: Or, maybe, it's the USCG in New Orleans. Sigh. In a way, that makes sense, because every map I seem to be getting shows the ocean off the Gulf of Mexico. It also matches up with this info from the USCG, which lists NMG as broadcasting on 8503.9, which means that I tune it on 8502.
Addendum2: Yep, it looks like New Orleans is where it's at. Here's a link to the schedule.. I've been doing my experiments around 11:00PM local, which is 07:00UTC. According to this schedule, at 07:25UTC, they rebroadcast the 72 hr surface forecast, which matches up nicely with what I received.
Addendum3: Here's a GOES IR image from New Orleans.
Addendum4: Here's the same image, in the pristine form you can get from the NOAA website: