Anomalous warmth covers much of the Northern Hemisphere. A focus on parts of Europe and the Asia-Pacific can be seen. (Climate Change Institute at the University of Maine)

(This story, first published on Thursday, was updated on Friday.)

Across the Northern Hemisphere, record-breaking heat has torched every continent this summer. Heading into the weekend, an intense heat wave is likely to threaten all-time high temperature records on Europe’s Iberian Peninsula, possibly boosting them to levels the continent has not previously observed. On the other side of the hemisphere, the Korean Peninsula is in the midst of days of record-breaking heat as well.

Throughout the summer much of the Northern Hemisphere has baked in above-normal temperatures. Just last week, parts of north-central Europe and Scandinavia witnessed some of their hottest weather ever recorded in July or any time of year. And here we are again.

From southern France through a good chunk of Spain and Portugal, high temperatures approaching and entering the 40s Celsius (roughly 104 Fahrenheit or greater) have already occurred, and more is anticipated in the days ahead. The images below highlight the region in Spain expected to see highs of 40 Celsius or higher through Monday.

These extreme temperatures are in large part thanks to the resilient heat dome that has dominated Europe’s summer weather for weeks. It is now reasserting itself.

On the Iberian Peninsula, where a handful of local heat records have already fallen in Portugal, temperatures are forecast to head even higher this weekend. In Spain, where several people have died from heat strokea heat wave warning is in effect through the weekend for much of the country.

Temperatures in these countries could near the highest levels ever observed both there and anywhere in Europe. Weather Underground’s Bob Henson notes the highest temperatures reliably measured in Portugal and Spain are 47.4 Celsius (117.3 Fahrenheit) and 47.3 Celsius (117.1 Fahrenheit).

European weather modeling (shown below) conservatively forecasts highs up to 44-45 Celsius (around 113 Fahrenheit). Numbers such as these would tickle all-time highs for these countries.


Forecast high temperatures for Saturday, Aug. 4. 44C is equal to 111F. All-time record highs in Europe are near 48C. (weathermodels.com, adapted by CWG)

But some weather models have shown temperatures approaching 50 Celsius (122 Fahrenheit) in Portugal, which would easily set a new all-time record for heat there and all of Europe.

Henson cautions, however, that “the expected pattern is so extreme that the surface-temperature predictions of forecast models have to be approached with a grain of salt.”

Caveats in mind, it’s not just weather models advertising historic heat. The official forecasting agency for the United Kingdom, UK Met Office, isn’t being shy about heat prospects, either.

Metro UK writes that, “Met Office meteorologist Luke Miall said the current record of 48°C (118°F) in Athens, in 1977 could be broken as blisteringly hot air sweeps in from Africa.” (Note: There is some debate whether this or a separate reading of 48.5 Celsius is the record.)


The browning of Europe over the past month. (NASA Worldview, adapted by CWG)

The heat is being fostered by sprawling and long-lasting high pressure. Under high pressure, rain tends to be tough to come by. This has led to an increase in drought in the United Kingdom, which had its driest first half of summer on record, and contributed to a record wildfire season in Sweden. A significant concern is that the blistering heat could stoke explosive wildfires over Portugal in the days ahead, and it is also anticipated that fire conditions will grow in other parts of Europe including Scandinavia heading into next week.

Not only Europe is sweltering. On both Thursday and Friday, Pyongyong, the capital of North Korea, managed a record high of 37.9 Celsius (100 Fahrenheit), breaking the record set on Wednesday. Records have been set in South Korea, as well, including the all-time high in the country at Hongcheon, where the temperature reached 41 Celsius. And among other notable readings, the warmest low temperature ever recorded in the capital of Seoul.

These records add to an ever-growing list of all-time record highs set around the Northern Hemisphere:

Collectively, all of these exceptional heat milestones are consistent with what is expected in a warming world, as concentrations of greenhouse gases from human activity continue to accumulate.

Capital Weather Gang’s Jason Samenow contributed to this post.