Houston, Jun 28 (IANS): A triple-digit heat wave is currently underway in Texas, pushing the state's power grid to new limits while expanding to other parts of the US South.
More than 55 million people in the US are presently under some form of heat advisory, watch or warning, according to the National Weather Service (NWS).
"The Gulf Coast and areas immediately inland most likely will see no breaks in the oppressive heat and humidity as we look forward to the Fourth of July holiday," Xinhua news agency quoted the National Oceanic and Atmospheric Administration's Weather Prediction Center as saying.
Around 90 afternoon high-temperature records could be broken across the US South, from Texas to the Mississippi Valley and parts of Florida.
Parts of Florida could get 43-degree heat early next week.
Forecasters said Tuesday was expected to be the warmest day of the week in parts of Texas, where a heat dome, which occurs when the atmosphere traps hot air over a certain area for days or weeks, remained stalled over.
Dallas is set to go six consecutive days without seeing temperatures drop below 26 degrees overnight, a June record for the city.
Houston, the fourth largest city in Texas, has had nine days for this month that haven't dropped below 26 degrees, nearly double what's typical for June.
San Antonio and Austin have already broken daily temperature records last week as the heat reached 40 and 41 degrees, respectively and were forecast to get triple-digit heat again, according to the NWS.
At least three hikers died in Texas last week after suffering heat-related fatigue, including a teenage boy and his stepfather in Big Bend National Park where temperatures rose to 48 degrees, the second-highest mark ever recorded in the state.
According to data provided by the Electric Reliability Council of Texas (ERCOT), total grid demand hit 80,144 megawatts on Monday evening.
ERCOT published a fact sheet earlier this month listing 80,148 MW as the all-time record.
This week's heat wave "may be more danger than a typical heat event, due to the longevity of near-record or record high nighttime lows and elevated heat index readings", forecasters at the Weather Prediction Center have warned.
Triple-digit temperatures and extreme humidity together make it feel hotter than 43 degrees in some of the region's most populous cities.
Meanwhile, overnight temperatures will also stay abnormally high, with potentially 180 nighttime records broken over the coming days, according to the NWS.
Climate change is widely blamed for causing heat waves to be more intense, longer-lasting and more frequent.