As we head into the last week of August, it is of interest to review aspects of this summer’s precipitation in Madison.
First of all, every one of the three traditional summer months has been wetter than normal with June, July, and August (through Aug 20) coming in at 0.26”, 1.55” and 2.02” above normal for a total surplus of nearly 4”.
In addition, though we have had a few really wet days – June 23 (2.48”), July 10 (2.01”) and August 10 (2.07”) – another aspect of this summer’s precipitation has been its remarkable regularity. From June 1 – August 20 we have had only ONE streak of more than 3 consecutive days without precipitation. That 9-day streak occurred from July 31 – August 8.
Perhaps equally remarkable is the fact that in June and July we had only 4 streaks of 3 consecutive days without precipitation. We have compiled statistics on such streaks for June/July going back to 2000. In that time only 8 June/Julys have had fewer rain-free streaks of 3 or more days than we did this year (2004 wins with only 2 such streaks!). So, by this measure, this has been a pretty unusual summer with regard to the regularity of rainfall.
In addition, this summer’s dry streaks have been the shortest in the last quarter century – the average longest streak is 7 days and no streak lasted longer than 3 days this June/July. (In case you are wondering, the record longest such streak since the turn of the century was 11 in 2021). So, if you have been thinking this has been an unusual summer weatherwise, there is good justification for that!
Steve Ackerman and Jonathan Martin, professors in the UW-Madison department of atmospheric and oceanic sciences, are guests on WHA radio (970 AM) at noon the last Monday of each month. Send them your questions at stevea@ssec.wisc.edu or jemarti1@wisc.edu.
