Waterloo hasn’t had more than an inch of rain in a single day since October 22, 2020. On that day it rained 2.94". The most amount of rain Waterloo has received since that date on a single day was .91" on May 8, 2021. Across Iowa, the month of May was the 13 th driest in 127 years of records. So far this year, it is currently the 47 th driest in 127 years. Locally, it’s currently the ninth driest year EVER in Black Hawk County and April was the driest April EVER in Waterloo with only .46" of precipitation. The all-time record for the driest June in Waterloo was in 1927 when only a total of .61” of rain fell. So far this month, Waterloo has received only a few sprinkles. The city averages just under five inches of rain in June.