What is the most rain ever recorded for May and June?

Dear Tom,
We’ve had so much rain this May and June. What is the most rain ever recorded for these two months?
— Ken Graham
Dear Ken,
Through Friday evening, the Chicago area has officially logged 15.05 inches of rain since May 1; 8.21 inches in May and 6.84 inches so far in June. If no additional rain fell the rest of the month, the 2018 May-June tandem would rank as the second wettest, runner-up to the 17.35 inches of rain received in May-June 1892. In May 1892, the city received 6.77 inches of rain, with the heaviest fall of 1.66 inches on May 5. June was incredibly wet, logging 10.58 inches, with the month’s largest daily rainfall of 3.04 inches on June 23. It is interesting to note that the second half of 1892 produced subpar rainfall with just 11.27 inches from July-December and below normal rainfall in all six months.