I think my post titles might be coming out of the Department of Redundancy Department, except for the date, since I got so far behind.
There were no Fog Banks between April 2 & April 21.
Great photo on Astronomy Picture of the Day of mammatus clouds
CoCoRaHS has a WeatherTalk Web seminar coming up on May 2. The topic Aviation Meteorology.
(I'm hopeful the talk was archived for us to see later)
ESPOD, Iridescent Clouds & Contrail
Reed Timmer tweeted a great supercell photo from April 20
AccuWeather has an article about the Great Lakes ice & the effect on spring weather.