A scorching heatwave in early summer that scorched large parts of Texas and Oklahoma in the past week swept across the Gulf Coast Tuesday, with dangerous heat forecasts reaching the Florida Keys.
In Austin, Texas, where the heat index soared to 118 degrees Fahrenheit last week — the highest on record in the city — officials were preparing to keep daily high temperatures above 100 « for the foreseeable future. » said Kevin Snipes, the city’s emergency directorate manager.
Ambulance calls and emergency room visits for heat exhaustion have increased in Austin and other cities, including Tulsa, Oklahoma, where electricity was out for tens of thousands of people for several days last week after strong storms followed by triple-digit heat.
The high temperatures have already proved fatal for some. A Florida teenager and his stepfather, who were hiking Friday in Big Bend National Park in south Texas, died as temperatures soared to 119 degrees Fahrenheit, the second highest ever in the state.
« We’re in extreme heat right now, » said Thomas VandenBerg, a park ranger in Big Bend. Growing demand for electricity to cool homes and businesses has also taken a toll on Texas’ independent power grid, though it appears to have held up so far.
Unusual early summer temperatures – daily highs in the 90s are more typical for much of the region in late June – are the result of a stubborn « heat dome » of high pressure that has persisted over much of parts of Oklahoma, Texas and northern Mexico for days.
Determining whether a particular heat wave is linked to climate change requires analysis. But even so, scientists are in no doubt that heatwaves around the world are getting hotter, more frequent, and longer-lasting. The 2018 National Climate Assessment, a major scientific report from 13 federal agencies, found that the frequency of US heatwaves has increased to six per year by 2010from an average of two a year in the 1960s.
Forecasters expect the current heat dome to drift north and east during the week, extending the brutally hot weather to parts of Louisiana, Arkansas, Mississippi, Alabama, Missouri, Tennessee, Georgia and Florida. The heat index — a measure of how the air feels that takes into account both temperature and humidity — will push well into the triple digits during the day in some of these places, and temperatures won’t cool much during the evening .
The pattern could continue across much of the South well into the Fourth of July holiday, with perhaps the most people affected on Wednesday and Thursday.
John Keef AND Jacey Fortin contributed.