There is/was a strong cold front running from the SW (Kansas?) up towards
the NE (Michigan?) so I would guess that the cold front caused some type of
ducting? The temperature differences on either side of this particular
frontal boundary is/are quite large.

Although ducting of this type, as I understand, is a phenomenon which more
commonly occurs on UHF/VHF frequencies.
Perhaps someone with more knowledge/experience will chime in with their
comments in regards to MW frequencies and approaching cold fronts.

wrote in message
oups.com...
Last night on the AM broadcast band, the stations up and down the East
Coast that traditionally boom in were not so strong.

The Canadian station on 740 which is usually all there is had some
obvious competition from stations in the SW... Texas/Oklahoma? Also the
stations from upstate New York which normally boom in had other signals
fading in and out against them.

And WGN which is not all that reliably received here in Washington DC
was booming in real strong.

Is this possibly related to the strong weather that has been moving
through the midwest (and is due to hit here on the E Coast tonight)? Or
is it just a sign of the end of Winter MW propogation?

Tim.