Don’t know about other parts of the country, but I would say in the greater NY metro area (including Long Island and the upper 1/2 of NJ) you’d need AT LEAST $600,000 per year in income to be considered “upper middle class” if you had any more than one child.
That’s a bit of an exaggeration. It’s about $300k to have a nice house in a good school district with most the trimmings in the NY suburbs — so $300k, maybe $350k for a two earning family given the costs of the second income. You can spend vastly more, but you don’t have to do so to hold your head high. $90k in deductible mortgage interest, property tax, and state income tax, $60k in federal income and payroll tax, and $150k for cost of living and savings.