Cicada watch: Billions could emerge as temperatures keep climbing

MIAMI VALLEY — Everyone is waiting for the BILLIONS of cicadas to emerge in southwest Ohio, and one key factor to getting these creepy-crawlers to emerge from the ground is the soil temperature.

The surface of the ground needs to reach 64 degrees for about a day for the cicadas to start to surface, said Wright State University biology professor Don Cipollini.

>> When will BILLIONS of cicadas emerge in the Miami Valley?

“That temperature is one that evolutionarily is ingrained in them, because it represents a temperature that there’s very little risk that they’ll freeze,” Cipollini said.

Meteorologist Kirstie Zontini looked at three different sources to help determine if the ground is warm enough. She said the warm stretch of 80 degree days and sunshine will likely lead to a wake up call if it hasn’t already happened.

>> Cicada Watch: Upload your photos & videos of the once-in-17-year brood!

Soil Temperature Estimation

This isn’t an exact number but it can be a good clue if we are getting close. Look at the high and low temperature from the past three days. Take the average each day and once you get those three numbers, average them together to get a rough estimate.

Subsurface Road Sensors

Another clue is looking at road sensors from ODOT. Their data shows the subsurface temperatures. These are read about 20 inches below the road, according to Matt Bruning from the Ohio Department of Transportation.

Weather Stations for Agriculture

Ohio State University College of has several weather stations across the state used for agriculture research. These sensors measure soil temperatures 2 inches and 4 inches below bare soil. This can be helpful to get a better view of what the soil would be like in nature where cicadas would likely burrow. The sensor in Clark County is now showing an average soil temperature of 64 degrees!

With more sun and warm weather in the forecast through at least the weekend, the soil will continue to warm up and you will likely start to notice the cicadas more and more, Zontini said.

Don’t forget to share your photos of the bugs on our FREE WHIO News app under Cicada Watch!