What does an El Nino summer mean for Illinois crops?
By RHIANNON BRANCH
FarmWeek
As tropical weather patterns suggest a shift to El Nino conditions, FarmWeek interviewed Eric Snodgrass, a principal atmospheric scientist with Nutrien Ag Solutions, to see what Illinois farmers should be watching as summer nears.
Q: What is the short-term weather forecast for Illinois?
A: The beginning of June is going to start off with much warmer temperatures, which a lot of growers in Illinois need. May was not a warm month, so to be able to get extra heat units into the ground is going to be huge for this crop. But we also don’t want to see extended time periods of dry weather, which is what I think we’re going to see finishing May and starting June.
Q: What does a shift to El Nino mean for Midwest crops?
A: Historically, when you have rapidly developing El Ninos, which we do this year, June does tend to be drier. But when you look at the same years, July tends to come in with quite a bit of storms and our crops tend to do OK with that. But if it’s ill-timed, maybe we stay dry too long into July and bring the rain later in the month rather than earlier, then you could be looking at a situation that is unfavorable for crop development. It’s just a little too far out to tell.
Q: How much impact does El Nino have in the Midwest during summer months?
A: We have to be careful with how much we attribute to El Nino. It’s going to be huge, but we’ll talk so much more about El Nino in the fall and winter than we will during the summer. The correlation between summer weather and El Nino is about 0.3%, which means you can only attribute about 9% of the variance of summer weather to El Nino and that’s not enough.
Q: Are you watching weather patterns in any other areas?
A: If I were going to make a call for a super hot and dry summer, I would need to see the Northeast Pacific. There’s a decently strong correlation with cold water off the west coast of North America to summer heat and drought stress in the Midwest. Right now those ocean temperatures are not cold. So that is another thing that points to a possible stormy summer rather than one that’s bone dry all the way through July and August. If on June 21, the solstice, I’m looking at the Northeast Pacific and it has cooled off dramatically, then I’m going to be really worried because that is going to start to give us a drier signal for July and August.
Q: Is there potential for Illinois to experience rapid onset drought like it did last fall?
A: Yes. But even though we’re drier for at least the next two weeks, the question is will it be dry longer term? For the next two weeks it is going to be wet to our south, and usually our biggest drought events start when it’s too dry to our south. If they’re humid and there’s a lot of soil moisture then the moisture goes right over the top of them comes to us. So, I’m not overly worried about rapid drought. If you were to call me back in two weeks and the dryness didn’t break, I’m going to start ringing the alarm bell. But if it is in fact just a two-week hiatus in the rainfall and we return wet again, it’s going to be huge for this crop.
Q: Does it look like 2026 will continue to be an active severe weather year?
A: We do think it will. But we’ll transition in June from having flow that generates thunderstorms that come out of the west and southwest and by July, a lot of our storm trajectory will be coming out of the northwest and we want that. That is a very healthy summer pattern for delivering rainfall.
This story was distributed through a cooperative project between Illinois Farm Bureau and the Illinois Press Association. For more food and farming news, visit FarmWeekNow.com.
