AccuWeather.com reports another sweltering heat wave is gripping a large part of the U.S., with at least 14 states hitting the 100-degree mark Monday and more than 40 surpassing 90 degrees. While it's already hot on the East Coast, the worst is on its way.

Areas along the Northeast's heavily-populated Interstate 95 corridor will have highs near or reaching 100 degrees by the end of the week as the steamy air spreads eastward from the Plains.

What is so impressive about this heat wave is the humidity that is accompanying it. Even places such as Minneapolis, Minn., have had AccuWeather.com temperatures rising near 120 degrees.

"It's like getting slapped in the face with a wet sponge when you walk outside," said AccuWeather.com Senior Meteorologist Bernie Rayno. "The thing about this heat wave is you have the heat ... you have the humidity ... and you have no wind."

With no wind during the day and temperatures not even dropping just below 80 degrees at night in many places, there is no relief.

By the end of the week, people in New York City, Philadelphia, and Washington, D.C., will face temperatures at or above 105 degrees.

"Temperatures will topple 100 degrees in the big cities," AccuWeather.com Senior Meteorologist Henry Margusity said in reference to the Northeast. "It's the hottest weather these cities have had since last July."

The positioning of the jet stream (an area of maximum winds high above the ground) is the major player in heat waves. When there is what meteorologists call a large "ridge" in the jet stream, areas that lie under that ridge can experience heat waves.

"A ridge is essentially a big bubble of hot air," Margusity explained.

A ridge is currently located over the central U.S. and has been sending temperatures soaring above 100 degrees from Texas to Montana and the Dakotas and into the upper 90s farther east.

A cold front moving into the northern Plains at midweek will help provide some cooling for Montana, the Dakotas, and Minnesota, as well as generate stronger winds ahead of its arrival.

Indiana State Health officials are offering hot weather tips to help Hoosiers cope with the rising temperatures.

"This is the time of the year for hot temperatures and it's very important that people take these heat advisories seriously," State Health Commissioner Gregory N. Larkin, M.D., said in a press release "These self-help measures are not a substitute for medical care but could help you recognize and respond promptly to warning signs of trouble. The best defense against heat-related illness is prevention. Staying cool and making simple changes in your fluid intake, activities, and clothing during hot weather can help you remain safe and healthy."

To avoid heat related health problems, the Indiana State Department of Health recommends:

- Drink plenty of cool water.

- Avoid prolonged exposure outdoors during high temperatures.

- If you do not have air conditioning, go to a public location that is air-conditioned just for a few hours. This can help your body maintain appropriate temperatures.

- Using fans as a source of relief when there is low humidity.

- Cool down with cool baths or showers.

- Wear loose-fitting, light colored clothing.

- Slow down from your normal pace.

- Avoid alcohol.

- Draw shades, blinds, and curtains in rooms exposed to direct sunlight.

- Never leave children and pets in parked cars, even with windows cracked open.

When temperatures reach 90 degrees (Fahrenheit) or greater, health officials caution that overexposure to the heat can be a concern. Young children and the elderly are at a greater risk for such heat-related illnesses as heat stroke, heat exhaustion, or heat cramps.

Heat cramps are muscular pains in the abdomen, legs, and arms that occur from strenuous activity and increased sweating. Heat exhaustion can develop after several days of high temperatures and low fluid intake. Heat stroke, also known as sunstroke or hyperthermia, is a life-threatening situation in which the body is unable to regulate its temperature and cannot cool itself down.

For more information about protecting yourself during extreme temperatures, check out the Centers for Disease Control and Prevention's "Extreme Heat: A Prevention Guide to Promote Your Personal Health and Safety" at http://www.bt.cdc.gov/disasters/extremeheat/heat_guide.asp.