WASHINGTON — Conditions this summer across much of the Corn Belt and Northeastern US trended warmer and wetter than normal. For the 3-month period of June – August 2018, maximum temperatures were largely near normal across much of the growing region. However, minimum temperatures trended much above average for over 80% of the contiguous United States which pushed average temperatures above normal as well for the Corn Belt. Precipitation during this time largely trended above to much above average. Pennsylvania, in fact, recorded its wettest summer in the last 124 years. Other key Corn Belt states such as Iowa and Indiana ranked as the 6th and 8th wettest summers in 124 years, respectively.
Breaking the summer down month by month, June in the Corn Belt mimicked the 3-month period as temperatures and precipitation both trended above to much above normal. Minimum temperatures during the month were well above normal with many key producing states trending in the top 5 warmest in 124 years. June minimum temperatures in Iowa were the hottest on record. Precipitation also trended above average with states including Iowa, Indiana, and Kentucky trending much above average. During July, weather trends were fairly different than June. Many states across the Corn Belt saw temperatures close to normal. While minimum temperatures in the Eastern Corn Belt were still slightly warmer than normal, maximum temperatures in Illinois, Iowa, and Nebraska trended slightly cooler than average. Precipitation trends were largely mixed for the month. Pennsylvania recorded its wettest July on record while just to its west, Indiana and Ohio trended slightly drier than normal. In the Western Corn Belt, South Dakota, Nebraska, and Kansas each trended slightly wetter than normal. Finally, during August, trends were once again wetter to much wetter than normal across the central and eastern Corn Belt. Minimum temperatures were largely above normal as well, although maximum temperatures were in line with the monthly average. The Northeast had record-breaking minimum temperatures for the month as all states from Maine to Maryland had the warmest low temperatures in 124 years for August.
September to date in the Corn Belt has trended largely wetter than normal, with the exception of the Dakotas. Remnants from Tropical Storm Gordon last week played a large part in these wetter trends, bringing rains to much of the Midwest, Mid-Atlantic, and Northeast. Temperatures have trended slightly above normal overall as well. As corn reaches maturity, currently 35%, and harvest gets underway, currently 5% complete, the weather during the rest of September looks generally favorable. While temperatures are forecast to continue to trend above normal, precipitation will be more mixed. Areas of Iowa, southern Minnesota, and Nebraska could trend a little on the wetter side, while Kansas to Indiana trend drier than normal. In the East, the remainder of September is expected to trend much wetter than normal, thanks in large part to Hurricane Florence which is expected to approach the Carolina coast later today (9/13) before making landfall tomorrow. While the storm will weaken after moving inland, Florence will be a slow-mover, dropping heavy rain on the Carolinas. In addition to dangerous storm surge, coastal and inland flooding due to rain are also expected. Widespread areas could see over a foot of rain, with others seeing 2’+.