OK here is the severe weather forecast for the continental USA for the period 201404 20 to 30. It is important to note that this period is between a lunar eclipse and solar eclipse on the 29th. So we have Tornado outbreak potential on 20th and 29th. Tornadoes and large number of hail events on 21-23rd and on the 28th. Large number of hail events (72+) on the 24th and 27th.
You will note on the forecast spread sheet that the 27th and 28th dates are in bold red font. These dates are predictions for a large number of hail events which have been generated by the Iasoberg Model. There are an average of 25 of these days per year based on NOAA data. The dates predicted by the model range from late April to mid July and vary from year to year. The above dates are the first ones for 2014.