Uff da is a Midwest saying I have heard from time to time. It always surprises me to hear someone say it. The first time I heard someone say “Uff da” I thought they had gas.
Wikpedia defines “Uff da” as an exclamation of Scandinavian origin that is relatively common in the Upper Midwestern states of the United States as a term for sensory overload. It can be used as an expression of surprise, astonishment, exhaustion, relief and sometimes dismay.
Here are some examples a friend gave me. He happens to be Scandinavian and from the Midwest so I consider him to be a good authority. Let me point out that some of these examples take place on a farm.
Trying to dance the polka to rock and roll music
Losing your wad of gum in the chicken yard
Arriving late at a lutefisk supper and getting served minced ham instead
Looking in the mirror and discovering you're not getting better, just older
Trying to pour two buckets of manure into one bucket
Having a mouse crawl up your leg when you're on a hayload
Eating hot soup when you've got a runny nose
Getting out of bed in the morning with a backache
Getting swished in the face with a cow's wet tail
Waking yourself up in church with your own snoring
Forgetting your mother-in-law's first name