Winter Sporadic-E-Like Propagation on 6 Meters

The question was asked: why do we see sporadic-E like propagation in November and December, when many of the variables like UV radiation and solar exposure are at a minimum, unlike the very active sporadic-E summer months?  Much like it was shown that North Atlantic transatlantic 6m propagation during the summer was made more possible by strategically placed weather storm systems, it looks like a similar effect with very strong jet stream boundaries also affect sporadic-E like communications during the winter months.  This citizen science study is another example how amateur radio can contribute to science, and illustrates the great potentials for studies using ham radio data.  We have many amateur radio stations on the air, using modes like FT8 which make contacts on propagation paths that we thought were previously impossible.