Weather tools assist farmers with management decisions

SYCAMORE, Ill. — The growing season in northern Illinois is expanding.

“The growing season over the last 30 years is about 20 days longer and it’s projected to increase by another 15 to 20 days over the next 20 to 30 years,” said Trent Ford, Illinois state climatologist at the University of Illinois.

Ford, who spoke at the Illinois Crop Management Conference hosted by U of I Extension at the DeKalb County Farm Bureau building in Sycamore, highlighted several tools that turn complex weather observations and climate data into information that’s helpful for those in the agricultural industry.

“Having the best information about weather and climate is not just how warm it is our how much rain is falling, but getting actionable information,” he said.

The Midwestern Regional Climate Center is a branch of National Oceanic and Atmospheric Administration.

“Every region has a center and they specialize in information on past and recent weather and climate conditions that ranges from how warm it was yesterday, how much rain or snow fell and how much snow is on the ground all the way to what the last month or year looked like,” Ford said.

Anyone can get daily as well as hourly information from all the stations.

“They have developed tools that are stakeholder driven like freeze probability and information on wind speed, wind direction and growing degree days,” Ford said.

“You can figure out what wind gusts look like on a single minute versus a daily average and you can look at extreme rankings such as how often we’ve hit a level of temperature or heat index.”

One of the programs on the MRCC website shows graphs of growing degree days.

“You can see the growing degree days in 2023 compared to the 30-year average,” Ford said.

“It will also estimate based off 108-day corn the number of days to reach silking or black layer,” he said. “Last year silking happened the last week or two of July, so within a season you can look at the growing degree days in your county relative to past years.”

Since this winter has been so mild, the soil temperatures are warmer than normal.

“We can compare that to a year we were also running ahead of normal for temperatures like 2012,” Ford said. “So, it’s not just a tool where you look back on what happened the last one to two years. Within a season you can see how you’re doing.”

The Illinois State Climatologist website has maps of precipitation for the last 30 and 90 days, as well as updated soil moisture and drought information.

“We have maps of water table levels, which is more relevant this year than the past couple of years,” Ford said.

Illinois soil moisture conditions are updated daily.

“One of our 19 stations is in DeKalb and we show soil moisture conditions at 4-, 8- and 20-inch depth,” the climatologist said. “The 4- and 8-inch amounts are bouncy this time of the year because of the frozen soils so the sensors wig out.”

For DeKalb, Ford said, the top 20 inches of soil is looking quite wet right now and in some cases above saturation.

“The water table is the barrier between the unsaturated and saturated soils and this time of the year we expect the water table to be 3- to 4-feet deep,” he said. “We came into this year a little deeper than normal.”

However, it is not like January 2013.

“We had almost a 20-feet deep water table after the 2012 drought, which really depleted not only the top soil layer, but pushed the water table way down,” Ford said.

“The average water table depth for August, September and October is 5-feet deep, so roots only have to penetrate 5 feet to find an unlimited supply of water,” he said.

“We see big drought impacts when water tables plummet and roots can’t find an adequate supply of water, so water table levels tell us a little more about when drought conditions turn into big drought problems than soil moisture can.”

The water table depth information is updated weekly.

“It is something to check, especially if we go into a drought,” Ford said.

Jamie Herring, who grows corn and soybeans on his farm near Esmond, said he is content with the soil moisture conditions at this time.

“I’d rather have it a little on the drier side than wetter,” he said.

Herring likes to analyze historical weather data to evaluate the impacts weather has on his farming operation.

“It could be a bad situation or maybe it is a little bit closer to the trend and you don’t realize that until you dive into the information,” he said.

The Climate Prediction Center has a hazards outlook page that features a 14-day outlook for hazards.

“Over the next two weeks this shows there is no threat of exceptionally high or low temperatures, so it’s going to be mild,” Ford said.

“For precipitation, we don’t see any risk of exceptionally wet conditions across the Midwest,” he said. “There is a slight risk of heavy precipitation on the West Coast.”

The center provides the same type of information for snow and wind. The data is updated every day and it includes expert discussion about all the hazards that are predicted for the next two weeks.

It is difficult to project the impact of changing climate conditions on crop yields in the future, the climatologist said.

“It requires a tremendous amount of data,” Ford said.

“The Climate Toolbox takes all of that information from models and makes it accessible for targeted analysis by 2050 or 2080,” he explained.

“For example, this is the high heat index days in Du Quoin, Illinois, and in the 1990s there were 60 days on average,” he said. “In the 2050s, that is projected to increase to 97 days, so the trend is upward.”

The Illinois State Water Survey provides a Pest Degree Day Calculator that includes 18 specialty crop pests and 12 commodity crop pests.

“It is based on temperature, growing degree days and other weather information,” Ford said.

“We can look at current conditions and projections of where a pest will be in its life stage over a growing season,” he said. “This year with such mild conditions, it’s a possibility that some of these pests may be more advanced in their life stage.”

The soil temperature measurements will be really helpful to predict when the cicadas will come out this year, Ford said.

“The brood in northern Illinois is really dense and very responsive to soil temperatures,” he said.