Despite some cloud cover, Wednesday was the warmest in Indianapolis since late April when we set the highest temperature so far this year. The one and only 80-degree day of 2021 fell on April 27 (82°). Wednesday’s high reached 79°.
Scanning weather records, this is the fewest number of 80° days in Indianapolis since 2006 and only among 13 years with so few. The lack of 80s in the month of May is a reflection of the cool month that we are having. May 2021 is the coolest in 24 years.
The pattern is evolving, and when it is complete by the end of the work week, we will have the warmest air of the year. For the first time this year, an upper-level high pressure, or dome of heat, will form in the southeast U.S.
This feature is more typical in the summer months, and when it develops, sinking air compresses and heats under the weight of the high, sending temperatures well above normal. Each of the next six days, or at least well into next week, will average above normal.
The once “cool” May is taking a turn.