Heat stress can take a significant toll on cattle this time of year. Current indications are you have reason for concern, given that the weather outlook is for July and August to deliver above-average temperatures across most U.S. cattle-feeding areas.
One helpful tool you can reference to stay abreast of predictions is the USDA-ARS Heat Stress Forecast Maps. While designed specifically for cattle feeders, the maps are a good reference tool for other beef producers and dairymen as well.
The heat stress forecast maps are made using seven-day forecasts based on four weather parameters – temperature, humidity, wind speed and cloud cover. Each parameter plays a significant role in the overall heat balance of feedlot cattle.
While on the site, you can also learn more about the following:
• Factors that contribute to heat stress in cattle, including genetics, health, production status, and previous exposure to heat stress.
• The role environmental factors play in heat stress, such as recent rains, high overnight lows (above 70 F), low or no air movement, high relative humidity, etc.
• Actions to take/not take before or during a heat stress event, such as not moving cattle, wetting cattle with large droplets of water (150-micron diameter sprinklers) and not using a fine mist.
The weekly forecasts are produced as a partnership of the USDA-ARS with National Oceanic & Atmospheric Administration (NOAA) National Weather Service and are conducted at the U.S. Meat Animal Research Center in Clay Center, Neb. Each forecast is national but is divided into six regions. Just click on the region you’re interested in, and you’ll be able to read a detailed report for that area.
You can find the maps here: https://www.ars.usda.gov/plains-area/clay-center-ne/marc/docs/heat-stress/main/