Houston temperatures ahead of the Memorial Day weekend are already soaring into the 90s, with humidity making those air temps feel more like 100 degrees, but if you’re not used to this heat, it could be dangerous.

While this week’s heat has been close to record-setting, it’s not totally unfamiliar to Southeast Texas — it’s just unusual for it to be here this early. Forecasters at the National Weather Service have been warning about the need to get acclimated to the early season heat because the humidity and relentless sunshine can take a harder toll on a body that still thinks it’s spring.

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“The average first day of 95-plus temperatures for the city of Houston is June 13, so this is an early season bout of heat and our bodies are not yet acclimated to it,” weather service forecaster Cameron Batiste wrote in a bulletin Wednesday. “This is occurring on a holiday weekend and we know that you may have outdoor plans, so please be sure to practice heat safety to protect yourselves and your loved ones.”

The weather service is recommending that you:

• Drink plenty of water to stay hydrated. Water is best because alcohol and some soft drinks can actually leave you dehydrated.
• Take frequent breaks from the sun and avoid strenuous outdoor activities during the hottest part of the day.
• Wear loose or lightweight clothing
• Always look before you lock your vehicle. Never leave a child or pet inside a vehicle, where temperatures can reach deadly levels in minutes on a hot day.
• If you are a pet owner, be mindful of pavement in the heat. If the ground is too hot for the palm of your hand, then it is too hot for
  their paws.

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Another factor adding to the heat is the level of moisture in the air, which can be indicated by dew points, or the temperatures at which dew forms or when relative humidity reaches 100%. Typically, the more saturated the air is with moisture, the higher the dew point, so Houston could expect oppressive mugginess and sticky air if the dew point is at least 65 degrees. This week, dew points are ranging from 73 to 77 degrees.

To make matters worse, Houston’s humidity, or the level of water vapor in the air, can make our perception of heat seem much hotter than the actual temperature. That’s because the body cools itself through the evaporation of sweat from our skin. But such evaporation isn’t as effective when there’s too much moisture already in the air.

The heat index takes that into account, which is why on Wednesday the actual air temperature might be 91 degrees but a high humidity level (say, a dew point of 74 degrees) can make it feel like it’s 101 instead.

What is heat safety?

Heat safety involves implementing measures to prevent heat-related illness and injury. It includes staying hydrated, wearing light and breathable clothing, and avoiding strenuous activities during the hottest parts of the day. Utilizing shade and air conditioning can help keep body temperatures regulated.

Heat safety also encompasses understanding the signs of heat exhaustion and heat stroke, such as heavy sweating, dizziness, and nausea, and knowing how to respond promptly to these symptoms.

Know signs of heat illnesses

Heat cramps, the first indication of heat stress, involve painful muscle cramps and spasms, usually in the abdomen and legs, accompanied by heavy sweating. Applying firm pressure on the muscles and sipping water can help, but avoid giving water if nausea is present. Seek medical attention if cramps last longer than an hour.

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Heat exhaustion involves heavy sweating, weakness, cool and clammy skin, and a rapid, weak pulse. Symptoms can also include dizziness, nausea, vomiting, headache, fainting, or muscle cramps. To lower body temperature, move the person to an air-conditioned room, apply cool, wet cloths, or have them sit in a cool bath. Seek immediate medical attention if symptoms persist longer than an hour.

Heatstroke is the most serious heat-related illness, marked by a body temperature of at least 103 degrees. Symptoms include a throbbing headache, dizziness, nausea, vomiting, red and dry skin, and a rapid but weak pulse. Fainting or loss of consciousness can occur without immediate treatment. Call 911 and move the person to an air-conditioned area, applying cool, damp cloths. Do not give fluids, as this can cause pulmonary edema, or fluid in the lungs. Delaying medical attention can be fatal.