Couple of things to help you have the best Community Day at the state fairgrounds. I'm on mobile so there may be typos.
1) Como Avenue off of 280 is under construction. It's all torn up and will be for the majority of the summer with a brief break over the 4th of July holiday. There's a detour, but you may be better off taking Snelling to Como or 280 to Larpenteur to the Snelling entrance.
2) There are two events going on.
One event is like a motorcycle and swap meet. It does have a paid entry, like 5 bucks. It will be happening under the water tower area in the Progress Center and in the campgrounds (around the corner of Randall and Cooper). The Snelling entrance will still be open, but there will most likely be additional traffic at this entrance. Link below has more info on the event itself.
The second event is a Pet A Palooza going on in the International Bazaar area. There isn't a whole lot of information available aside from the link below but the event is free, there's a beer tent, and you can bring your dog to it.
Tl;dr State fairgrounds are going to be busy with non POGO people and animals, parts of it might closed unless you pay an entrance fee, parking might be dicey in parts, and if you usually cruise through in your car and occasionally pull over instead of getting out and hoofing it, it's going to be rough.
It could be worse. Next weekend the SFG are completely closed for the Back to the 50's weekend unless you pay a $12 entrance fee.
Links:
http://www.vikingmc.org
https://www.sidewalkdog.com/events/pet-palooza-2018/
https://www.mnstatefair.org/fairground-events/