The Ohio Agricultural Research and Development Center (OARDC) Agricultural Research Stations located throughout the state have two and four inch soil temperatures monitored on an hourly basis. This will be the final soil temperature update this season.
Figure 1. Average daily air temperature (average of maximum and minimum daily temperatures; red-dashed), two and four inch soil temperatures for spring 2019 (brown and blue-solid, respectively), and two and four inch five-year average soil temperatures (brown and blue-dotted, respectively) for four OARDC stations from around Ohio (Northwest, Wooster, Western, and Piketon; see map insets). Conditions for 2019 are plotted through May 12th.
Figure 1 shows that while soil temperatures were running close to the five-year averages earlier in the week, they ended on a downturn. All fours stations are currently cooler than their five-year averages. Of note, 2” and 4” soil temperatures at the Northwest station in Custar were 6-8°F below their five-year averages as of Sunday, May 12, 2019. Historically, soil temperatures warm fairly rapidly over the next couple of weeks, and with a warmer air mass set to move into the region by mid- week, soil temperatures should moderate this week.
Figure 2. Accumulated precipitation (percent of normal based on 1981-2010 climatological mean) for Ohio for the period January 1-May 12, 2019. Stars designate a selection of OARDC Agricultural Research Stations from around the state. The accumulated precipitation (in inches) is provided in the table on the right, along with number of days with 0.1” of precipitation or greater since April 1. 2019. Figure provided by the Midwest Regional Climate Center (https://mrcc.illinois.edu/).
Figure 2 shows the updated percent of normal precipitation that has fallen since January 1. The entire state of Ohio is currently running above average, with much of the state between 125-150% above average. Areas across western and southwest Ohio have seen greater than 150% of normal precipitation for the year to date (dark green shaded). The table to the right of the figure indicates the amounts that have fallen at the same selected OARDC sites used for soil temperatures in Figure 1. All of these sites are above average.
While the period May 2018 – April 2019 was the second wettest May to April period on record since 1895, the amount of precipitation since April 1, 2019 has not set records. However, the frequency of precipitation is high, with many areas across the state having received at least 0.01” or greater of precipitation on more than 50% of days since April 1, 2019. Thus, windows for adequate drying this spring have been limited, preventing the necessary fieldwork and planting.
For more complete weather records for all of the OARDC research stations, including temperature, precipitation, growing degree days, and other useful weather observations, please visit http://www.oardc.ohio-state.edu/weather1/.