[HCDX] An unusual log on 1640kHz

[Lighthouse9564@xxxxxxx]

Okay, here's one to "stump the star" DXers:
Even with the geomagnetic disturbance I can
not think of an explanation for this and in 20+
years of DXing have never had this happen:

1640kHz AM (Mediumwave),  0255-0310+ UTC,  
(which is 2255-2310 local time)    NOAA
Weather Service broadcast continuous loop 
audio tape.  I am hearing the electronic voice of the 
NOAA weather service message and foreceast for 
Northwest Pennsylvania and others in the region !!!     
The other stations I usually hear on 1640kHz are 
also seem to be present.   This NOAA service is normally 
on VHF around 162MHz FM - depending on where one lives.  
(SINPO = 23332)   (Silvi, Mentor Ohio USA, April 21)