SUMMER'S FIRST HOT SPELL GRIPS REGION

A high pressure system spreading over much of the southern United States is responsible for the high heat and humidity that are giving the region its first taste of summer.

The temperature reached 90 degrees at 4 p.m. Friday in Cape Girardeau, and the relative humidity was at 61 percent. The combination created a heat index of 100 degrees.

Not much change is forecast through Wednesday. Temperatures the first week of June are running 3 to 5 degrees above normal highs and lows.

David Humphrey, a meteorologist with the National Weather Service at Paducah, Ky., said the high pressure building overhead is causing the air to sink and warm, negating any chance of rainfall through Wednesday.

Precipitation in Cape Girardeau during May was 2.82 inches. Normal for the month is 4.7 inches, said Dr. Al Robertson, a Cape Girardeau climatologist. May usually is the wettest month of the year here.

Humphrey said the high pressure system also is allowing the return of southwesterly winds, which are bringing in the humidity.

Even though humidity levels may drop during the day, the afternoons will be muggier because the air mass is warmer and able to hold more water content.

The heat and humidity can affect elderly people and the very young much more than other age groups. This is especially true of elderly people who have diabetes, heart or circulatory diseases or have had a stroke.

Heat disorders can manifest as heat stroke, heat cramps and heat exhaustion, according to the University of Missouri Extension Service. Dizziness, weakness, mental confusion and a fast pulse may precede heat stroke, when a victim's temperature can range from 104 to 106 degrees. Heat cramps are painful leg and abdominal spasms due to loss of salts and water through sweating. Heat exhaustion also is due to excessive sweating and can be accompanied by symptoms of dizziness, faintness and nausea.

Medical assistance is always indicated.

Precautions against these conditions include eating less -- especially fatty foods -- drinking plenty of water and wearing light colors.

During periods of high heat and humidity, pets should be kept inside if there is no adequate shade outside.

Hot weather stress is a concern to livestock producers when heat and humidity are high. Animals that get too hot can become weak, experience muscle tremors, collapse and die, said Roger Eakins, a livestock specialist with the University of Missouri Extension Service in Jackson.

When temperatures reach the low 90s, humidity above 75 percent falls into the alert category, and levels above 79 percent are in the danger category.

Livestock in confined areas such as feedlots and holding pens are especially vulnerable.

The forecast calls for temperatures and precipitation above normal through June 14. The 30-day outlook is for below normal temperatures and above normal rainfall, while the forecast through August is for lower-than-normal temperatures and normal precipitation.