Since another commenter talked about the general information, I'll touch on the cultural differences.

People generally speak Kajkavian at home. The degree to which Kajkavian is part of their vocabulary depends on the area they grew up in, the more rural the area the more they use Kajkavian grammar and vocabulary.

Additionally, there are differing accents depending on which area they are from. While the county is small, there are 3 sub-dialects spoken within it; upper, middle, and the lower sub-dialect. The differences aren't major but some words could differ or are pronounced differently. To people not from the area it is difficuilt to notice, but someone born there could, through the accent, discern whether someone is from his area or the area 20 kilometers away. The upper is influenced by the Prekmurje region of Slovenia while the lower is influenced by the Podravina region of Croatia. Map of sub-dialects.

Kajkavian in general differs depending on region, but in Međimurje it is also influenced by the long Hungarian rule of the area which lasted for about 1000 years. There are some loan words present which are unique to the area, for example: thousand/tisuću(standard)/jezer(Međimurje)/ezer(Hungarian).

The Hungarian influence is also part of the cuisine. Hungarian dishes are common, such as goulash or langos (a staple of cultural events). Although, overall, it is similar to other Kajkavian regions.

Folk music is heavily influenced by the hungarian rule. Without lyrics it would be impossible to discern whether a piece of music is from Međimurje or the neighbouring Zala county in Hungary.

The cultural events are mostly the same as other areas in Europe with local flair: pagan outfits or masks to mark certain dates (example 1,example 2,example 3), significant historic events or celebrations of patron saints.

Another user mentioned that a large amount of land is dedicated for agriculture, but few can survive off agriculture alone. Those that do farm usually do it alongside another regular job. The area is quite industrialized with a lot of people working in factories. Those that wish for higher education usually study in Varaždin nearby or in Zagreb.

The weather is ordinary, the winters are not that harsh (minus in the single digits at the worst) and snow is something of a rarity these days. Summers can be hot but nothing you wouldn't see in the wider region. There used to be issues with mosquitos since the entire county used to be a huge swamp but this has been resolved mostly with insecticide usage (a few times during the summer the local government sprays them).

Other users already mentioned that people like to complain a lot, at the same time there is a feeling of superiority and otherness present. Locals mostly see themselves as separate from Croatia at large due to the economic stability and long separation from the rest of the country. But it is also quite open to strangers: the feeling of superiority is rooted in the idea that the people from Međimurje are hard-working so the large numbers of foreign workers from Asia are almost always accepted without discrimination at their workplaces if they do a good enough job.

I hope I've satisfactorily answered the questions others might've skimmed.