A punishing heatwave now bears down on the western United States and Mexico just as deadly floods keep tearing through parts of South Africa.

Forecasters say a ridge of high pressure will drive temperatures far above seasonal norms across western parts of the US and Mexico this week. Reports indicate daytime highs could run 10-15C above average in some areas. In California and Arizona, the US National Weather Service has issued heat advisories, while extreme heat warnings cover some locations on Monday and Tuesday, including Palm Springs, where temperatures could reach 40-43C.

Key Facts

  • Western US and Mexico face temperatures 10-15C above average.
  • Heat advisories and extreme heat warnings cover parts of California and Arizona.
  • Palm Springs could see highs of 40-43C.
  • Deadly flooding continues across South Africa's Western and Northern Cape.

The heat will not stay put. Forecasts suggest temperatures will climb into the high 30s celsius across a broader swath of the region before the system shifts east toward the Midwest later this week. That progression matters because it expands the number of communities facing dangerous daytime heat and warmer nights that can deepen health risks.

The week’s weather story stretches across continents: extreme heat tightens its grip on North America while floodwaters continue to batter South Africa.

At the same time, South Africa faces a very different emergency. A continuing deluge has hit parts of the Western Cape and Northern Cape, and the flooding has turned deadly. The overlap of these disasters underscores how quickly weather extremes can strain emergency services, disrupt daily life, and test public infrastructure in very different ways.

What happens next will shape the human toll. Officials in the US and Mexico will likely focus on heat safety, power demand, and the risk to outdoor workers and vulnerable residents as the hot air spreads east. In South Africa, attention remains fixed on flood impacts and recovery. The broader lesson feels hard to ignore: extreme weather no longer arrives as an isolated event, and communities must prepare for fast-moving threats that land with little margin for error.