We’ve made it! Meteorological summer started on June 1, but the official start of summer isn’t until June 20. The days are longer, temperatures have risen, and my allergies are in full swing. I let the dogs out last night, and there was still quite a bit of light in the sky just before 10:00 PM EDT, which also makes it hard to get the kids to go to bed at a decent time. Who cares, though? It’s summer, right???
June started much cooler than usual, with many areas in central and northern Indiana experiencing temperatures in the mid-30s. Indiana Dunes National Park recorded a low of 34°F on June 2, marking the coldest June temperature ever recorded at this station since records began in 1989. While this record doesn’t span that many years, Farmland 5 NNW, located in Randolph County, recorded a low of 35°F, matching the record set on June 1, 1966 (records dating back to 1893). Reports of frost emerged in some locations as a result. However, just two days later, Indiana Dunes National Park reached a high of 89°F. Overall, average temperatures across the state have been near normal to 1-2°F below normal, particularly in northern Indiana. This trend has remained fairly consistent since May 1 and is evident in the modified growing degree day (MGDD) accumulations. Much of the Midwest is 40-80 heating units behind normal since May 1 (Figure 1). This is not a significant deviation and is not expected to cause much delay in crop maturity. Temperatures are rising and will continue to warm this month, as the Climate Prediction Center expects Indiana to end June with above-normal temperatures.
Figure 1: MGDD accumulations and departure from the climatological average for May 1 to June 10, 2025.
In May, precipitation levels across much of northwestern Indiana fell below normal, leading to the development of abnormally dry (D0) and moderate drought (D1) conditions, according to the US Drought Monitor. However, precipitation increased slightly in June within this region. There was a slight improvement on June 10, with the D1 area decreasing by just over 4 percent (Figure 2). D0 conditions on the eastern edge of D1 improved due to last week’s heavy rains. Much of central and southern Indiana received above-normal rainfall, which caused localized ponding and flooded crops. On June 5, many stations reported over 3 inches of rain, with Lagro 3.5 ESE (White County) recording the highest at 3.55 inches. That morning, my CoCoRaHS gauge recorded 2.62 inches in southwestern Howard County, while just a few miles to the east, the total was 3.21 inches. Quite a difference!
Figure 2: US Drought Monitor Map for June 10, 2025.
In the near term, it looks like we may see continued above-normal rain. The Climate Prediction Center has increased confidence in above-normal precipitation through June 25, although this month has equal chances for above-normal or below-normal precipitation. Similarly, summer precipitation also presents equal chances, but we should have more information next week when the new outlooks will be released.