Temperatures at Houston’s official climate observation site, Bush Intercontinental Airport, are expected to surpass 90 degrees every day this week.

With some acute changes in the broader weather pattern starting on Monday, we could see our humidity climb and push heat index values, or “feels like” temperatures close to the 100-degree mark.

Those living without electric power in Southeast Texas after last week’s deadly and destructive wind storms should continue to make heat safety and heat health their priority, the National Weather Service said in a forecast bulletin Saturday.

LIVE UPDATES: Residents without power urged to take caution as temperatures reach 90s

“Heat index values will be in the upper 90s once again, but at least we’ll have a noticeable southeasterly breeze this time around,” weather service meteorologist Cameron Batiste wrote in the bulletin. “That southeasterly breeze is a blessing for now (especially for those still without power), but will be part of our downfall later on in the week when you see what the additional humidity does to our heat index values.”

Foggy commute, muggy afternoon

Clear skies and light winds will continue to allow overnight and predawn air temperatures to cool down enough reach the dew point, or the temperature at which dew forms and relative humidity is 100%. With so much moisture evaporating from rain-saturated soils, Houston will continue to see areas of patchy fog during the morning commute Monday until 10 a.m.

Once the fog clears, Houston temperatures on Monday will climb to an afternoon high of 91 degrees, getting a boost from sunshine and warm southerly winds carrying moisture-rich air from the Gulf of Mexico.

That inflow of balmy, tropical air means rising humidity levels that will only amplify the summer-like heat growing in Southeast Texas, forecasters said.

“This leads to heat index values seeing a slight rise into the 96-100 (degree) range,” Batiste said in the bulletin. “The upward trend in heat index values don’t stop there, so it remains very important to keep heat safety as a top priority… especially for those still without power.”

Humidity, or the level of water vapor in the air, can make our perception of heat seem much hotter than the actual temperature because the body cools itself through the evaporation of sweat from our skin. But 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 the actual air temperature might be 92 degrees but a high humidity level (say, a dew point of 72 degrees) can make it feel like it’s 100 instead.

Houston also won’t get much relief from the heat in the evenings anymore because overnight low temperatures in the city will stay above at least 75 degrees this week, according to the weather service’s extended forecast.

The weather service is reminding the public to take these steps to manage the danger and stresses of heat:

• Drink plenty of water.
• Take frequent breaks, avoid strenuous outdoor activities during the hottest part of the day.
• Know the signs of heatstroke and heat exhaustion.
• Always look before you lock your vehicle. Don’t ever leave a child or pet inside a vehicle.
• For dog owners, if the ground is too hot for the palm of your hand, then it is too hot for their paws.

Tuesday and beyond

Tuesday and Wednesday’s forecasts looks similar to Monday’s with some slight adjustments. Houston will be partly sunny on both days, again with high temperatures around 91 degrees. Meanwhile, the southerly winds kick up some on Tuesday, to 10 to 15 mph with gusts as strong as 20 mph. Both Tuesday and Wednesday nights will be mostly cloudy with lows around 76 degrees.

“Heat continues to be the main concern in this forecast period,” the weather service said in its bulletin, adding that “peak heat index values will be in the low 100s daily (generally 100 to 105), so make sure all heat safety precautions are being taken to stay safe!”