Counties in the lower Tidewater consistently make up the hottest region in Virginia on average, according to 100-plus years of temperature data amassed by the National Oceanic and Atmospheric Administration.

While blazing summer heat can stress certain crops, some like it hot, especially peanuts and cotton, said Virginia Cooperative Extension agent Elizabeth Cooper. She currently works with farmers in Suffolk and Surry and Sussex counties, where these summer crops are a cornerstone of the regional economy, along with corn and soybeans.

“There’s a reason we’re one of the northernmost areas producing cotton and peanuts on the Eastern Seaboard,” Cooper explained. “The heat we have out here is what drives the production and yield of both of those crops. They need what we call heat units, or growing degree days, for the crops to meet certain growth stages at certain times and produce the yields we need to be profitable.”

State statistician Herman Ellison of the National Agricultur...