September has gotten off to a warmer-than-normal start through September 7, averaging 2.1◦F above normal across the state (Figure 1). Northern Indiana temperature departures were larger than the rest of the state as temperatures ranged from 2.4-3.2◦F above normal. Maximum temperatures were at or below normal through the state, as minimum temperatures ran 1-6◦F above normal. Evening temperatures have been pleasant for most, as many celebrated Labor Day with outside activities. Rain and wet conditions did impact weekend plans for some, especially in southern Indiana.
Figure 1: September 1-7, 2022, climate division (cd) and state average temperatures (temp), normal temperatures (norm), temperature deviations (dev), average precipitation (prcp), normal precipitation (norm), precipitation deviations (dev), and percent of normal precipitation (percent) compared to the 1991-2020 climatological averages.
Northern Indiana was dry this past week with precipitation less than 20 percent of normal. Central and Southern Indiana, however, received between 130-327 percent of normal precipitation. Most of the rain in south-central Indiana was measured on September 4, 2022, where 1-2 inches fell. Columbus, Indiana measured 3.97 inches of rain so far, with over 2.08 inches measured on the morning of September 5. The September 6th US Drought Monitor showed relief to the Abnormally Dry (D0) conditions in southern Indiana and persistent dryness through most of the northern half of the state (Figure 2). Modified Growing Degree Days (MGDD) have accumulated to over 2400 units in the north to over 3200 units in southern counties (Figure 3, Left). Most of the state continued to see above normal MGDD departures (Figure 3, Right).
Figure 2: September 6, 2022 US Drought Monitor.
Figure 3. Left – Modified Growing Degree Day accumulations April 1- September 6, 2022. Right – Modified Growing Degree Day accumulations from April 1-September 6, 2022, represented as the departure from the 1991-2020 climatological average.
Northern Indiana could get around an inch of rain between now and mid-September, as indicated by the latest computer predictions. As of now, southern Indiana has lower chances of rain through this period. The Climate Prediction Center 6-10-day outlook (September 12-16) has elevated confidence in below-normal temperatures and near-normal to below-normal precipitation. The 8-14-day outlook has medium confidence in above-normal temperatures and leaning toward near-normal to slightly below-normal precipitation. For the entire month, the Climate Prediction Center expects above normal temperatures and equal chances for above-normal or below-normal precipitation. As for harvest season, the September-October-November outlook has increased confidence in above-normal temperatures and below-normal precipitation. This should hopefully allow a smooth harvest season (knocks on wood).
