I am having ongoing issues with my OTA HD reception. My antennas face south and in the late afternoon, like now (1815 EDT) it breaks up and even loses the signal. I was wondering if this is being caused by solar interference? In the morning, I have no problems at all and once the sun is down it also stops.
What you are most likely experiencing is a common phenomenon. Early mornings and throughout the evening the troposphere settles and the path of the signal changes significantly, typically enhancing signal levels dramatically. Late in the afternoon, after a full day of atmospheric heating, a lot of instability is present, destroying these enhancements.
If you are in a marginal signal location, these diurnal changes will wreak havoc with your reception.
The problem isn't solar radiation, but it is caused by the sun's effect on the earth/water bodies and ultimately the troposphere. (heating/instability).
This same phenomenon (although MUCH stronger) allows watching TV stations from the East coast from here in the midwest, especially on UHF. The seasonal tropo enhancement can be astonishing, while the diurnal is more benign.
The only suggestion I have is to get a better antenna to increase your fade margin. While I can measure the changes I just discussed here, I never see a change in reception because my signal levels are well above the fade margin.