Understanding weather patterns can get you ahead in the fields

Farmer standing by tractor

SALEM, Ohio — Climate risk in agriculture is likely to be greater in the next 20 years, making the management of that risk increasingly important. Keeping track of weather patterns, and simply having knowledge of the weather, can be an extremely important tool in a farmer’s toolbox, according to Elwynn Taylor, climatologist at Iowa State University.

Taylor spoke at the Ohio Farm Bureau Young Ag Professionals Conference in late January, on how to get ahead of the seemingly unpredictable weather.

Harsh year ahead

Somewhere around the year 2025, Taylor predicts we will experience the harshest year of the century, which he said occurs every 89 years. The last harshest year was the Dust Bowl in the 1930s. 1936 was the hottest summer of the century and the worst drought. The coldest, snowiest winter on record was in 1935-1936. So what can we expect around 2025 is “something similar to the Dust Bowl,” said Taylor.

According to Taylor, weather isn’t all that unpredictable and has a series of trends that can be traced back centuries. Weather patterns tend to occur in a series of 18 consistent years and 25 variable years. Our current variable weather pattern started in 2012.

El Nino

“We are currently involved in a very strong El Nino, the strongest since 1950,” said Taylor, who added that the El Nino is a friend of the Midwest farmer. What happens when the El Nino ends could be troubling or could have no affect at all.

According to Taylor, when the El Nino ended in 1982-1983 and ’87-’89, the Corn Belt experienced a strong drought. The next strong El Nino (ending in ’93) resulted in flooding and the strongest of this series (ending in ’97-’98) did not result in any bad yields.

Producers can track the patterns of the El Nino here.

Marketing and weather

So how can farmers stay on top of the markets even when the weather isn’t playing nice? If they understand what is happening with the weather, Taylor said they can predict the market. When the USDA releases its early crop predictions, its reports are based on current conditions and an estimate of the future harvest based on normal weather conditions. The market then adjusts to what it feels the price ought to be, based on these conditions presented by the USDA.

If the farmer is paying attention to the weather and what it is doing to his or her crop, he can have an idea of what the forecast will be when harvest approaches. “This is probably the very best bit of information a farmer can have — just to know if the market is too high or too low,” he said.

Growing Degree Days

One way producers can make their own estimates on how their crop compares to the market is by keeping track of growing degree days, which are key to the development of the crop. Plant development is strongly related to the accumulation of temperatures above that plant’s threshold or base temperature, below which little growth occurs — or growing degree days.

Early in the season, growing degree days are controlled by daytime temperatures and in the middle of summer, they are dictated by overnight temperatures. Producers can calculate growing degree days by finding the average daily air temperature — subtract the daily minimum temperature from the daily maximum and divide by two — and subtracting the lower base temperature of that particular crop.

For example, corn’s lower base temperature is 50 degrees F. If the high for the day was 86 degrees and the low was 56 degrees, the average for the day would be 68 degrees. The growing degree days would then equal (68 degrees minus 50 degrees) 18.

If the daily minimum temperature is less than the base of 50 degrees, then the minimum temperature is set as 50 degrees. If the maximum temperature is greater than 86 degrees (corn’s maximum threshold) than the maximum temperature is set to 86 degrees. Soybeans can also be calculated using this minimum and maximum temperature.

If the growing degree days are greater than usual — meaning the air temperature is considerably higher than the base for that plant’s growth — the crop will reach maturity faster. Once a plant reaches maturity, it can no longer develop any more grain, or put on anymore pounds, explained Taylor.

More information on Growing Degree Days and how you can use them in your farm operation can be found here.

Pay attention

Farmers can make money off volatility, Taylor said. If the producers understands the trends in the weather, they will have an idea of what the market will predict and the farmer can take advantage of this. If the prices are too low, buy insurance, and if the prices are high, sell some and take advantage of the market. “Marketing is simple, it’s just not easy,” said Taylor.

Two-month outlook

After having higher than normal temperatures in January and early February, the Midwest sunk below freezing going into the middle of the month. According to Jim Noel, service coordination hydrologist at the NOAA/National Weather Services Ohio River Forecast Center, featured in the  Ohio State University’s C.O.R.N. newsletter, the weather will turn warmer than normal again by late February and precipitation will be normal to slightly above normal.

March will have temperatures above normal and drastically better than the previous two years. Rainfall will be normal to slightly below normal for the month.

Put weather data to work for you

Growing degree days are published weekly during the growing season in the USDA’s crop reports and can be searched by county.

Farmers can also review previous year growing degree days by visiting Iowa Mesonet website and clicking on “Ag weather” and “Automated Data Plotting” and using the first option, which includes “GDD/SDD” (growing degree days and stress degree days) and selecting “select plot type.”

From here, producers can pick a station in the Corn Belt or their region to see what the growing degree days were for the growing year. Farmers can use this tool to compare their current season to a previous year.

Another resource for comparing previous years is the Useful to Usable website or U2U and using the “decision dashboard.” Clicking on “AgClimate View” and selecting a weather station (red dot) in the producer’s area will get a graph that shows climate data, climate average, yield trend and comparisons from previous years.



Up-to-date agriculture news in your inbox!

Previous articleFAMACHA scoring to identify parasite risk in small ruminants
Next articleWhy you say #ThankstoFFA
Catie Noyes lives in Ashland County and earned a bachelor's degree in agriculture communications from The Ohio State University. She enjoys photography, softball and sharing stories about agriculture. Formerly a reporter for the Farm and Dairy, Catie is now pursuing her master's degree in education.



We are glad you have chosen to leave a comment. Please keep in mind that comments are moderated according to our comment policy.

Receive emails as this discussion progresses.