Conditions on the AM band were great today. Occasionally, around the time of the winter solstice, some amount of skywave propagation can remain in effect all day. Normally there is no skywave propagation on mediumwave frequencies during daylight hours because of the ionizing effect of the sun on the D layer of the ionosphere. This layer absorbs signals at these frequencies, preventing them from propagating further. At night, the D layer disippates, which allows signals at mediumwave frequencies to pass through it to the higher F layer, which reflects them back to earth. This is the reason for long distance propagation on the AM band at night. However, around the time of the winter solstice the days are the shortest of the year, and the sun is at the lowest elevation in the sky. So the D layer does not get as strongly ionized and skywave propagation on mediumwave doesn't entirely disappear during the daylight hours. I would expect this phenomenon would be stronger, more frequent, and occur over a longer period of time at more northerly latitudes. Here in southern Ontario I've only ever seen it happen within a couple of weeks of the winter solstice. And it was happening today.
I logged the following stations. I heard more stations than this, but as I was driving I didn't think it was worth stopping to log stations I knew I'd heard before. Four of them turned out to be new catches, which is a fantastic haul. Combined with the three new ones I caught in Ottawa earlier, I got seven new stations on mediumwave today. I can't remember the last time I got so many new ones. This brings the overall mediumwave log count to 963.
- WPNI, 1430, Amherst MA at 1810 UTC (2:10 p.m. local time) with fair signal. 5 kW. Playing folk music. ID as WUMB. WUMB is the University of Boston FM station on 91.9, WPNI is carrying its programming at the present time. First time logging. Received in Ottawa, ON.
- WENE, 1430, Endicott NY at 1815 UTC with fair signal. Sports. ID as "The Team" and gave location as Binghampton. Received in Ottawa. Relog.
- WEOK, 1390, Poughkeepsie NY at 1835 UTC, poor signal. 5 kW. Heard ID and frequency. Received in Carleton Place, ON. First time logging.
- WNIO, 1390, Youngstown OH at 1858 UTC. Fair-poor signal. 9.5 kW. Sports talk, ID as "The Sports Animal". ESPN. Callsign ID on the hour. Received in Carleton Place. Relog.
- WROW, 590, Albany NY at 2015 UTC. Poor signal. Christmas music, ID as "Magic 590". Relog.
- WHBL, 1330, Sheboygan WI at 2100 UTC, around sunset local time. Poor signal. 5 kW. News with items about local events in Wisconsin. Mentions of Sheboygan. Received on Highway 7 in central Ontario. First time logging.
- WIGN, 1550, Briston TN at 2130 UTC with poor signal. 35 kW. Religious. Several IDs and location heard. Received in Havelock, ON. First time logging.