Fox News Weather Center

Dairy Costs Could Spike From High Summer Heat

Consumers could begin to see a rise in dairy costs on the shelves after late June and early July dealt a stretch of record-breaking high temperatures to the West, and the coming weeks will yield prolonged heat for the Midwest.

Keeping livestock healthy and productive requires a delicate balance. Temperatures that are either too warm or too cold affect the energy levels in dairy cows, and in turn, cause them to produce less milk.

Dairy cows experiencing heat stress in the summer months are less productive. Photo by Scott Bauer and the Agricultural Research Service of the United States Department of Agriculture.

Marie teVelde, Director of Communications for California Dairies, explained that cows will eat less when it's hotter outside and milk production decreases as a result.

"Once temperatures abate, cows recover and return to normal production levels," she said.

Consumers are only really affected if hot weather is widespread and persists for a long period of time.

According to Expert Senior Meteorologist Alex Sosnowski and Head of's Long-Range Forecasting Team Paul Pastelok, heat will be coming in and out of the Plains over the next 30 days.

For the next two weeks, the Midwest will have temperatures in the 80s and 90s.

The Southwest will catch a break as building monsoon conditions trim the heat down for the Four Corners area, but temperatures will increase over the Great Basin and West.

The mercury will be especially high come September when this region will reach its hottest point of the year.

"On average, dairy cows start to experience heat stress when the temperature/humidity index is 72 degrees," Dr. Tamilee Nennich, Associate Professor of Animal Sciences at Purdue University, explained in a Purdue Dairy Digest Podcast.

"New research has shown that high-producing dairy cows may start to experience heat stress at temperatures closer to 68 degrees."

Drought conditions have persisted over the Midwest, where a large percentage of the nation's dairy supplies come from. If the high heat and low precipitation continue for much of the summer, milk prices could potentially rise.

When high, prolonged heat is expected, dairy cow farmers take measures to minimize the impacts.

"California dairymen take the comfort of their cows seriously and work hard to meet the animal's needs," teVelde said. "During the hot summer months, adequate shade and water is provided to minimize the effects of high temperatures."

To combat heat issues, Nennich recommends that dairy farmers use fans and soakers in their barns but warns that to be effective, both need to be used properly. Fans need to be positioned to move the air over the cows and need to be kept clean. Soakers need to produce droplets of water that are big enough to wet cows to their skin. If water droplets are too small, they will sit on the cows' fur and may actually work to insulate heat instead of helping to cool.

"Keeping cows cool during the summer will help them be both comfortable and productive," she said.