It’s been an active summer in Ohio with hot temperatures, flooding rains, and 45 confirmed tornadoes so far.
But fall is coming, and AccuWeather’s Senior Meteorologist and Lead Long-Range Expert Paul Pastelok has a preview of what we can expect for the upcoming season. He spoke with WYSO's Mike Frazier to share more.
This transcript has been lightly edited for length and clarity.
Paul Pastelok: El Nino is coming on full blast and it will have a major influence on our pattern. And this fall we'll be on the northern edge of some of the heaviest rainfall that does develop this season. So I think we're still going to see some wet weather from time to time, but it'll be dry for periods, especially early on. And that should mean for some warmer temperatures to start the fall. And then we should back off a little bit as the fall goes on, but fall foliage should be pretty decent. The flood threat may be slightly higher during the middle of the season, but overall I think it should be a decent fall.
Mike Frazier: So El Nino is gonna have a big influence on our fall weather.
Pastelok: It will. I mean, there'll be other factors, but this will be, it's so strong, the signal, the confidence level that it will produce what it normally does for our area.
It generally puts us in the northern fringe of the heaviest rainfall and precipitation. We don't get a lot of snow. It's not generally cold enough half the time during El Nino winters, but late fall, we do anticipate a little bit of chilly air in November that could give us maybe a little bit of snowfall then, but we think that could have a bigger impact as we get into the colder season.
Frazier: Now in layman's terms, what is El Nino?
Pastelok: El Nino is basically the warming of the waters in the equatorial Pacific Ocean, and what it does is it kind of affects the upper patterns that set up. Especially as we get into the colder seasons of late fall, winter, and early spring, we see the influence of this.
And the stronger it is, the stronger its influence will be.
And again, it brings more storms from the southern states. And generally they either go west to east or sometimes they will come north and that's usually where our moisture source is. And a lot of times too the arctic air gets cut off from Canada and we don't get the severity of cold that you normally would have in the opposite phase which is called La Nina.
Frazier: So El Nino is basically warming the atmosphere and that's influencing moisture content and where that moisture goes and how warm it is?
Pastelok: Yeah, when you have warmer waters, a lot of times you have more evaporation, and more moisture is actually being put into the atmosphere. And so when that happens, and systems pick these up, the rate of the precipitation is stronger. And so you can get wetter systems a lot of times when you're having El Nino.
Frazier: Now, we've gone through a couple of weeks of a pretty heavy rainfall here in Southwest Ohio, some localized flooding. Our soils are kind of saturated. Do you think that might increase some flooding risk for parts of the upcoming fall?
Pastelok: Yeah, I think it was again in September we'll see kind of a downturn. There'll still be some shower or thundershower activity early on, but I think it'll ease back and those river levels should come down a little bit. The soil moisture should ease up and dry out because the dew points at night will be lower. Humidity will be lowered and we should dry out a little bit, but as we get later into the season, we'll start to see more of a southern storm track coming up.
Frazier: Now when you say storm track, can you translate that, put that in layman's terms?
Pastelok: Yeah, what that means is that the main systems that drive our weather, the precipitation, the rain, the snow, whatever, generally has an area that kind of just kind of locks in sometimes. And in recent years, we've seen a lot of our storms coming out of Canada and dropping southward into the region, bringing us some rain, some snow during the late fall. But this year, the southern storm track looks like it's going to be much stronger. And it could pick up a lot of moisture from the warm waters of the Gulf of Mexico and even into the Eastern Pacific and bring a lot that northward at times. And so that's the concern with El Nino is that you can see that happen more frequently, especially as you get later into fall and the winter season.
Frazier: Okay, so to rehash and to summarize the fall forecast in 20, 30 words.
Pastelok: I think we're going to see a decent fall foliage this year. We're going to get some precipitation, some rain. The flooding will ease back a little bit early on, but could come back later on thanks to El Nino. Not much cool air, but I think fairly mild overall.
Frazier: So the cooling will have to wait until later on in the season.
Pastelok: Yeah, it looks like. And we may not have a lot. It's one of those years where the cool air may come in pockets like in November and then maybe later on in the winter, but in between it may be more cloudier days, cloudier nights, which keeps temperatures up.
