On July 16th, the national Climate Prediction Center released the climate outlooks for August (Figure 1) and the August-September-October (Figure 2) period. Both outlooks are indicating a significant probability for above-normal temperatures. Precipitation is likely to be above normal for the southern two-thirds of Indiana in August, but there is little-to-no guidance for the 3-month, August-September-October period.
Figure 1. Temperature (left) and precipitation (right) probabilities for above- or below-normal conditions for August. Source: NOAA Climate Prediction Center
Figure 2. Temperature (left) and precipitation (right) probabilities for above- or below-normal conditions for the August-September-October period. Source: NOAA Climate Prediction Center.
Abnormally dry conditions are starting to ease across the state, due to recent rainfall. However, evapotranspiration has still been relatively high due to the warm temperatures, so dry conditions remain spotty across the state. Fortunately, temperatures are likely to be below normal through August 7th, which may help lower evapotranspiration rates. Modified growing degree-day accumulations are very comparable to recent years in the northern part of the state, but are still lagging in the southern half (Figures 3 and 4).
Figure 3. Modified accumulated growing degree-day units for April 1 – July 28, 2020.
Figure 4. Comparison of accumulated modified growing degree days for April 1 through July 28 for 2016 through 2020.