My calendar of Nevada history says that on this date in 1846, the Donner Party broke camp in the Truckee Meadows (modern Reno) heading west toward the Sierra Nevada. However, a more credible source puts their departure date around October 27-28. The latter date is more consistent with their tragic appointment with catastrophe, although it is possible to get snow in the Sierra this early in the season.
This year, I think there might be a whole lot of people cheering for snow and rain, and lots of it, to descend upon California, Oregon, and the rest of the west being tortured with wildfires.
(If you plan to come to Westercon 74 from California via I-80 and Reno, consider stopping at Donner Memorial State Park, which is just off the freeway, so it's easily accessible for a short visit.)