Winter Bash is as much fun as it is, due, in small part, due to it taking place once a year - adding some incentive to participate during the slower Christmas-New Year festive season, when visits, contributions etc tends to decline.

A 'Summer Bash', while potentially a lot of fun, would potentially dilute the effectiveness (and fun) of Winter Bash.

And as @random said, join us here in the Southern Hemisphere for the Summer "Winter Bash".

Winter Bash is as much fun as it is, in small part, due to it taking place once a year. The Winter Bash adds some incentive to participate during the slower holiday season when visits, contributions, etc. tend to decline.

A 'Summer Bash', while probably a lot of fun, would potentially dilute the effectiveness (and fun) of Winter Bash.

And as @random said, join us here in the Southern Hemisphere for the Summer "Winter Bash".